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/* $OpenBSD: pf.c,v 1.634 2009/02/27 12:37:45 henning Exp $ */
/*
* Copyright (c) 2001 Daniel Hartmeier
* Copyright (c) 2002 - 2008 Henning Brauer
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* Effort sponsored in part by the Defense Advanced Research Projects
* Agency (DARPA) and Air Force Research Laboratory, Air Force
* Materiel Command, USAF, under agreement number F30602-01-2-0537.
*
*/
#ifdef __FreeBSD__
#include "opt_inet.h"
#include "opt_inet6.h"
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#endif
#ifdef __FreeBSD__
#include "opt_bpf.h"
#include "opt_pf.h"
#ifdef DEV_BPF
#define NBPFILTER DEV_BPF
#else
#define NBPFILTER 0
#endif
#ifdef DEV_PFLOG
#define NPFLOG DEV_PFLOG
#else
#define NPFLOG 0
#endif
#ifdef DEV_PFSYNC
#define NPFSYNC DEV_PFSYNC
#else
#define NPFSYNC 0
#endif
#ifdef DEV_PFLOW
#define NPFLOW DEV_PFLOW
#else
#define NPFLOW 0
#endif
#else
#include "bpfilter.h"
#include "pflog.h"
#include "pfsync.h"
#include "pflow.h"
#endif
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/filio.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/kernel.h>
#include <sys/time.h>
#ifdef __FreeBSD__
#include <sys/random.h>
#include <sys/sysctl.h>
#include <sys/endian.h>
#define betoh64 be64toh
#else
#include <sys/pool.h>
#endif
#include <sys/proc.h>
#ifdef __FreeBSD__
#include <sys/kthread.h>
#include <sys/lock.h>
#include <sys/sx.h>
#else
#include <sys/rwlock.h>
#endif
#ifdef __FreeBSD__
#include <sys/md5.h>
#else
#include <crypto/md5.h>
#endif
#include <net/if.h>
#include <net/if_types.h>
#include <net/bpf.h>
#include <net/route.h>
#ifdef __FreeBSD__
#ifdef RADIX_MPATH
#include <net/radix_mpath.h>
#endif
#else
#include <net/radix_mpath.h>
#endif
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/tcp.h>
#include <netinet/tcp_seq.h>
#include <netinet/udp.h>
#include <netinet/ip_icmp.h>
#include <netinet/in_pcb.h>
#include <netinet/tcp_timer.h>
#include <netinet/tcp_var.h>
#include <netinet/udp_var.h>
#include <netinet/icmp_var.h>
#include <netinet/if_ether.h>
#ifdef __FreeBSD__
#include <netinet/ip_fw.h>
#include <netinet/ipfw/ip_fw_private.h> /* XXX: only for DIR_IN/DIR_OUT */
#endif
#ifndef __FreeBSD__
#include <dev/rndvar.h>
#endif
#include <net/pfvar.h>
#include <net/if_pflog.h>
#include <net/if_pflow.h>
#include <net/if_pfsync.h>
#ifdef INET6
#include <netinet/ip6.h>
#include <netinet/in_pcb.h>
#include <netinet/icmp6.h>
#include <netinet6/nd6.h>
#ifdef __FreeBSD__
#include <netinet6/ip6_var.h>
#include <netinet6/in6_pcb.h>
#endif
#endif /* INET6 */
#ifdef __FreeBSD__
#include <machine/in_cksum.h>
#include <sys/limits.h>
#include <sys/ucred.h>
#include <security/mac/mac_framework.h>
extern int ip_optcopy(struct ip *, struct ip *);
#endif
#ifdef __FreeBSD__
#define DPFPRINTF(n, x) if (V_pf_status.debug >= (n)) printf x
#else
#define DPFPRINTF(n, x) if (pf_status.debug >= (n)) printf x
#endif
/*
* Global variables
*/
/* state tables */
#ifdef __FreeBSD__
VNET_DEFINE(struct pf_state_tree, pf_statetbl);
VNET_DEFINE(struct pf_altqqueue, pf_altqs[2]);
VNET_DEFINE(struct pf_palist, pf_pabuf);
VNET_DEFINE(struct pf_altqqueue *, pf_altqs_active);
VNET_DEFINE(struct pf_altqqueue *, pf_altqs_inactive);
VNET_DEFINE(struct pf_status, pf_status);
VNET_DEFINE(u_int32_t, ticket_altqs_active);
VNET_DEFINE(u_int32_t, ticket_altqs_inactive);
VNET_DEFINE(int, altqs_inactive_open);
VNET_DEFINE(u_int32_t, ticket_pabuf);
VNET_DEFINE(MD5_CTX, pf_tcp_secret_ctx);
#define V_pf_tcp_secret_ctx VNET(pf_tcp_secret_ctx)
VNET_DEFINE(u_char, pf_tcp_secret[16]);
#define V_pf_tcp_secret VNET(pf_tcp_secret)
VNET_DEFINE(int, pf_tcp_secret_init);
#define V_pf_tcp_secret_init VNET(pf_tcp_secret_init)
VNET_DEFINE(int, pf_tcp_iss_off);
#define V_pf_tcp_iss_off VNET(pf_tcp_iss_off)
struct pf_anchor_stackframe {
struct pf_ruleset *rs;
struct pf_rule *r;
struct pf_anchor_node *parent;
struct pf_anchor *child;
};
VNET_DEFINE(struct pf_anchor_stackframe, pf_anchor_stack[64]);
#define V_pf_anchor_stack VNET(pf_anchor_stack)
VNET_DEFINE(uma_zone_t, pf_src_tree_pl);
VNET_DEFINE(uma_zone_t, pf_rule_pl);
VNET_DEFINE(uma_zone_t, pf_pooladdr_pl);
VNET_DEFINE(uma_zone_t, pf_state_pl);
VNET_DEFINE(uma_zone_t, pf_state_key_pl);
VNET_DEFINE(uma_zone_t, pf_state_item_pl);
VNET_DEFINE(uma_zone_t, pf_altq_pl);
#else
struct pf_state_tree pf_statetbl;
struct pf_altqqueue pf_altqs[2];
struct pf_palist pf_pabuf;
struct pf_altqqueue *pf_altqs_active;
struct pf_altqqueue *pf_altqs_inactive;
struct pf_status pf_status;
u_int32_t ticket_altqs_active;
u_int32_t ticket_altqs_inactive;
int altqs_inactive_open;
u_int32_t ticket_pabuf;
MD5_CTX pf_tcp_secret_ctx;
u_char pf_tcp_secret[16];
int pf_tcp_secret_init;
int pf_tcp_iss_off;
struct pf_anchor_stackframe {
struct pf_ruleset *rs;
struct pf_rule *r;
struct pf_anchor_node *parent;
struct pf_anchor *child;
} pf_anchor_stack[64];
struct pool pf_src_tree_pl, pf_rule_pl, pf_pooladdr_pl;
struct pool pf_state_pl, pf_state_key_pl, pf_state_item_pl;
struct pool pf_altq_pl;
#endif
void pf_init_threshold(struct pf_threshold *, u_int32_t,
u_int32_t);
void pf_add_threshold(struct pf_threshold *);
int pf_check_threshold(struct pf_threshold *);
void pf_change_ap(struct pf_addr *, u_int16_t *,
u_int16_t *, u_int16_t *, struct pf_addr *,
u_int16_t, u_int8_t, sa_family_t);
int pf_modulate_sack(struct mbuf *, int, struct pf_pdesc *,
struct tcphdr *, struct pf_state_peer *);
#ifdef INET6
void pf_change_a6(struct pf_addr *, u_int16_t *,
struct pf_addr *, u_int8_t);
#endif /* INET6 */
void pf_change_icmp(struct pf_addr *, u_int16_t *,
struct pf_addr *, struct pf_addr *, u_int16_t,
u_int16_t *, u_int16_t *, u_int16_t *,
u_int16_t *, u_int8_t, sa_family_t);
#ifdef __FreeBSD__
void pf_send_tcp(struct mbuf *,
const struct pf_rule *, sa_family_t,
#else
void pf_send_tcp(const struct pf_rule *, sa_family_t,
#endif
const struct pf_addr *, const struct pf_addr *,
u_int16_t, u_int16_t, u_int32_t, u_int32_t,
u_int8_t, u_int16_t, u_int16_t, u_int8_t, int,
u_int16_t, struct ether_header *, struct ifnet *);
static void pf_send_icmp(struct mbuf *, u_int8_t, u_int8_t,
sa_family_t, struct pf_rule *);
void pf_detach_state(struct pf_state *);
void pf_state_key_detach(struct pf_state *, int);
u_int32_t pf_tcp_iss(struct pf_pdesc *);
int pf_test_rule(struct pf_rule **, struct pf_state **,
int, struct pfi_kif *, struct mbuf *, int,
void *, struct pf_pdesc *, struct pf_rule **,
#ifdef __FreeBSD__
struct pf_ruleset **, struct ifqueue *,
struct inpcb *);
#else
struct pf_ruleset **, struct ifqueue *);
#endif
static __inline int pf_create_state(struct pf_rule *, struct pf_rule *,
struct pf_rule *, struct pf_pdesc *,
struct pf_src_node *, struct pf_state_key *,
struct pf_state_key *, struct pf_state_key *,
struct pf_state_key *, struct mbuf *, int,
u_int16_t, u_int16_t, int *, struct pfi_kif *,
struct pf_state **, int, u_int16_t, u_int16_t,
int);
int pf_test_fragment(struct pf_rule **, int,
struct pfi_kif *, struct mbuf *, void *,
struct pf_pdesc *, struct pf_rule **,
struct pf_ruleset **);
int pf_tcp_track_full(struct pf_state_peer *,
struct pf_state_peer *, struct pf_state **,
struct pfi_kif *, struct mbuf *, int,
struct pf_pdesc *, u_short *, int *);
int pf_tcp_track_sloppy(struct pf_state_peer *,
struct pf_state_peer *, struct pf_state **,
struct pf_pdesc *, u_short *);
int pf_test_state_tcp(struct pf_state **, int,
struct pfi_kif *, struct mbuf *, int,
void *, struct pf_pdesc *, u_short *);
int pf_test_state_udp(struct pf_state **, int,
struct pfi_kif *, struct mbuf *, int,
void *, struct pf_pdesc *);
int pf_test_state_icmp(struct pf_state **, int,
struct pfi_kif *, struct mbuf *, int,
void *, struct pf_pdesc *, u_short *);
int pf_test_state_other(struct pf_state **, int,
struct pfi_kif *, struct mbuf *, struct pf_pdesc *);
void pf_route(struct mbuf **, struct pf_rule *, int,
struct ifnet *, struct pf_state *,
struct pf_pdesc *);
void pf_route6(struct mbuf **, struct pf_rule *, int,
struct ifnet *, struct pf_state *,
struct pf_pdesc *);
#ifndef __FreeBSD__
int pf_socket_lookup(int, struct pf_pdesc *);
#endif
u_int8_t pf_get_wscale(struct mbuf *, int, u_int16_t,
sa_family_t);
u_int16_t pf_get_mss(struct mbuf *, int, u_int16_t,
sa_family_t);
u_int16_t pf_calc_mss(struct pf_addr *, sa_family_t,
u_int16_t);
void pf_set_rt_ifp(struct pf_state *,
struct pf_addr *);
int pf_check_proto_cksum(struct mbuf *, int, int,
u_int8_t, sa_family_t);
#ifndef __FreeBSD__
struct pf_divert *pf_get_divert(struct mbuf *);
#endif
void pf_print_state_parts(struct pf_state *,
struct pf_state_key *, struct pf_state_key *);
int pf_addr_wrap_neq(struct pf_addr_wrap *,
struct pf_addr_wrap *);
int pf_compare_state_keys(struct pf_state_key *,
struct pf_state_key *, struct pfi_kif *, u_int);
#ifdef __FreeBSD__
struct pf_state *pf_find_state(struct pfi_kif *,
struct pf_state_key_cmp *, u_int, struct mbuf *,
struct pf_mtag *);
#else
struct pf_state *pf_find_state(struct pfi_kif *,
struct pf_state_key_cmp *, u_int, struct mbuf *);
#endif
int pf_src_connlimit(struct pf_state **);
int pf_check_congestion(struct ifqueue *);
#ifdef __FreeBSD__
int in4_cksum(struct mbuf *m, u_int8_t nxt, int off, int len);
VNET_DECLARE(int, pf_end_threads);
VNET_DEFINE(struct pf_pool_limit, pf_pool_limits[PF_LIMIT_MAX]);
#else
extern struct pool pfr_ktable_pl;
extern struct pool pfr_kentry_pl;
struct pf_pool_limit pf_pool_limits[PF_LIMIT_MAX] = {
{ &pf_state_pl, PFSTATE_HIWAT },
{ &pf_src_tree_pl, PFSNODE_HIWAT },
{ &pf_frent_pl, PFFRAG_FRENT_HIWAT },
{ &pfr_ktable_pl, PFR_KTABLE_HIWAT },
{ &pfr_kentry_pl, PFR_KENTRY_HIWAT }
};
#endif
#ifdef __FreeBSD__
#define PPACKET_LOOPED() \
(pd->pf_mtag->flags & PF_PACKET_LOOPED)
#define PACKET_LOOPED() \
(pd.pf_mtag->flags & PF_PACKET_LOOPED)
#define STATE_LOOKUP(i, k, d, s, m, pt) \
do { \
s = pf_find_state(i, k, d, m, pt); \
if (s == NULL || (s)->timeout == PFTM_PURGE) \
return (PF_DROP); \
if (PPACKET_LOOPED()) \
return (PF_PASS); \
if (d == PF_OUT && \
(((s)->rule.ptr->rt == PF_ROUTETO && \
(s)->rule.ptr->direction == PF_OUT) || \
((s)->rule.ptr->rt == PF_REPLYTO && \
(s)->rule.ptr->direction == PF_IN)) && \
(s)->rt_kif != NULL && \
(s)->rt_kif != i) \
return (PF_PASS); \
} while (0)
#else
#define STATE_LOOKUP(i, k, d, s, m) \
do { \
s = pf_find_state(i, k, d, m); \
if (s == NULL || (s)->timeout == PFTM_PURGE) \
return (PF_DROP); \
if (d == PF_OUT && \
(((s)->rule.ptr->rt == PF_ROUTETO && \
(s)->rule.ptr->direction == PF_OUT) || \
((s)->rule.ptr->rt == PF_REPLYTO && \
(s)->rule.ptr->direction == PF_IN)) && \
(s)->rt_kif != NULL && \
(s)->rt_kif != i) \
return (PF_PASS); \
} while (0)
#endif
#ifdef __FreeBSD__
#define BOUND_IFACE(r, k) \
((r)->rule_flag & PFRULE_IFBOUND) ? (k) : V_pfi_all
#else
#define BOUND_IFACE(r, k) \
((r)->rule_flag & PFRULE_IFBOUND) ? (k) : pfi_all
#endif
#define STATE_INC_COUNTERS(s) \
do { \
s->rule.ptr->states_cur++; \
s->rule.ptr->states_tot++; \
if (s->anchor.ptr != NULL) { \
s->anchor.ptr->states_cur++; \
s->anchor.ptr->states_tot++; \
} \
if (s->nat_rule.ptr != NULL) { \
s->nat_rule.ptr->states_cur++; \
s->nat_rule.ptr->states_tot++; \
} \
} while (0)
#define STATE_DEC_COUNTERS(s) \
do { \
if (s->nat_rule.ptr != NULL) \
s->nat_rule.ptr->states_cur--; \
if (s->anchor.ptr != NULL) \
s->anchor.ptr->states_cur--; \
s->rule.ptr->states_cur--; \
} while (0)
static __inline int pf_src_compare(struct pf_src_node *, struct pf_src_node *);
static __inline int pf_state_compare_key(struct pf_state_key *,
struct pf_state_key *);
static __inline int pf_state_compare_id(struct pf_state *,
struct pf_state *);
#ifdef __FreeBSD__
VNET_DEFINE(struct pf_src_tree, tree_src_tracking);
VNET_DEFINE(struct pf_state_tree_id, tree_id);
VNET_DEFINE(struct pf_state_queue, state_list);
#else
struct pf_src_tree tree_src_tracking;
struct pf_state_tree_id tree_id;
struct pf_state_queue state_list;
#endif
RB_GENERATE(pf_src_tree, pf_src_node, entry, pf_src_compare);
RB_GENERATE(pf_state_tree, pf_state_key, entry, pf_state_compare_key);
RB_GENERATE(pf_state_tree_id, pf_state,
entry_id, pf_state_compare_id);
static __inline int
pf_src_compare(struct pf_src_node *a, struct pf_src_node *b)
{
int diff;
if (a->rule.ptr > b->rule.ptr)
return (1);
if (a->rule.ptr < b->rule.ptr)
return (-1);
if ((diff = a->af - b->af) != 0)
return (diff);
switch (a->af) {
#ifdef INET
case AF_INET:
if (a->addr.addr32[0] > b->addr.addr32[0])
return (1);
if (a->addr.addr32[0] < b->addr.addr32[0])
return (-1);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
if (a->addr.addr32[3] > b->addr.addr32[3])
return (1);
if (a->addr.addr32[3] < b->addr.addr32[3])
return (-1);
if (a->addr.addr32[2] > b->addr.addr32[2])
return (1);
if (a->addr.addr32[2] < b->addr.addr32[2])
return (-1);
if (a->addr.addr32[1] > b->addr.addr32[1])
return (1);
if (a->addr.addr32[1] < b->addr.addr32[1])
return (-1);
if (a->addr.addr32[0] > b->addr.addr32[0])
return (1);
if (a->addr.addr32[0] < b->addr.addr32[0])
return (-1);
break;
#endif /* INET6 */
}
return (0);
}
#ifdef INET6
void
pf_addrcpy(struct pf_addr *dst, struct pf_addr *src, sa_family_t af)
{
switch (af) {
#ifdef INET
case AF_INET:
dst->addr32[0] = src->addr32[0];
break;
#endif /* INET */
case AF_INET6:
dst->addr32[0] = src->addr32[0];
dst->addr32[1] = src->addr32[1];
dst->addr32[2] = src->addr32[2];
dst->addr32[3] = src->addr32[3];
break;
}
}
#endif /* INET6 */
void
pf_init_threshold(struct pf_threshold *threshold,
u_int32_t limit, u_int32_t seconds)
{
threshold->limit = limit * PF_THRESHOLD_MULT;
threshold->seconds = seconds;
threshold->count = 0;
threshold->last = time_second;
}
void
pf_add_threshold(struct pf_threshold *threshold)
{
u_int32_t t = time_second, diff = t - threshold->last;
if (diff >= threshold->seconds)
threshold->count = 0;
else
threshold->count -= threshold->count * diff /
threshold->seconds;
threshold->count += PF_THRESHOLD_MULT;
threshold->last = t;
}
int
pf_check_threshold(struct pf_threshold *threshold)
{
return (threshold->count > threshold->limit);
}
int
pf_src_connlimit(struct pf_state **state)
{
int bad = 0;
(*state)->src_node->conn++;
(*state)->src.tcp_est = 1;
pf_add_threshold(&(*state)->src_node->conn_rate);
if ((*state)->rule.ptr->max_src_conn &&
(*state)->rule.ptr->max_src_conn <
(*state)->src_node->conn) {
#ifdef __FreeBSD__
V_pf_status.lcounters[LCNT_SRCCONN]++;
#else
pf_status.lcounters[LCNT_SRCCONN]++;
#endif
bad++;
}
if ((*state)->rule.ptr->max_src_conn_rate.limit &&
pf_check_threshold(&(*state)->src_node->conn_rate)) {
#ifdef __FreeBSD__
V_pf_status.lcounters[LCNT_SRCCONNRATE]++;
#else
pf_status.lcounters[LCNT_SRCCONNRATE]++;
#endif
bad++;
}
if (!bad)
return (0);
if ((*state)->rule.ptr->overload_tbl) {
struct pfr_addr p;
u_int32_t killed = 0;
#ifdef __FreeBSD__
V_pf_status.lcounters[LCNT_OVERLOAD_TABLE]++;
if (V_pf_status.debug >= PF_DEBUG_MISC) {
#else
pf_status.lcounters[LCNT_OVERLOAD_TABLE]++;
if (pf_status.debug >= PF_DEBUG_MISC) {
#endif
printf("pf_src_connlimit: blocking address ");
pf_print_host(&(*state)->src_node->addr, 0,
(*state)->key[PF_SK_WIRE]->af);
}
bzero(&p, sizeof(p));
p.pfra_af = (*state)->key[PF_SK_WIRE]->af;
switch ((*state)->key[PF_SK_WIRE]->af) {
#ifdef INET
case AF_INET:
p.pfra_net = 32;
p.pfra_ip4addr = (*state)->src_node->addr.v4;
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
p.pfra_net = 128;
p.pfra_ip6addr = (*state)->src_node->addr.v6;
break;
#endif /* INET6 */
}
pfr_insert_kentry((*state)->rule.ptr->overload_tbl,
&p, time_second);
/* kill existing states if that's required. */
if ((*state)->rule.ptr->flush) {
struct pf_state_key *sk;
struct pf_state *st;
#ifdef __FreeBSD__
V_pf_status.lcounters[LCNT_OVERLOAD_FLUSH]++;
RB_FOREACH(st, pf_state_tree_id, &V_tree_id) {
#else
pf_status.lcounters[LCNT_OVERLOAD_FLUSH]++;
RB_FOREACH(st, pf_state_tree_id, &tree_id) {
#endif
sk = st->key[PF_SK_WIRE];
/*
* Kill states from this source. (Only those
* from the same rule if PF_FLUSH_GLOBAL is not
* set)
*/
if (sk->af ==
(*state)->key[PF_SK_WIRE]->af &&
(((*state)->direction == PF_OUT &&
PF_AEQ(&(*state)->src_node->addr,
&sk->addr[0], sk->af)) ||
((*state)->direction == PF_IN &&
PF_AEQ(&(*state)->src_node->addr,
&sk->addr[1], sk->af))) &&
((*state)->rule.ptr->flush &
PF_FLUSH_GLOBAL ||
(*state)->rule.ptr == st->rule.ptr)) {
st->timeout = PFTM_PURGE;
st->src.state = st->dst.state =
TCPS_CLOSED;
killed++;
}
}
#ifdef __FreeBSD__
if (V_pf_status.debug >= PF_DEBUG_MISC)
#else
if (pf_status.debug >= PF_DEBUG_MISC)
#endif
printf(", %u states killed", killed);
}
#ifdef __FreeBSD__
if (V_pf_status.debug >= PF_DEBUG_MISC)
#else
if (pf_status.debug >= PF_DEBUG_MISC)
#endif
printf("\n");
}
/* kill this state */
(*state)->timeout = PFTM_PURGE;
(*state)->src.state = (*state)->dst.state = TCPS_CLOSED;
return (1);
}
int
pf_insert_src_node(struct pf_src_node **sn, struct pf_rule *rule,
struct pf_addr *src, sa_family_t af)
{
struct pf_src_node k;
if (*sn == NULL) {
k.af = af;
PF_ACPY(&k.addr, src, af);
if (rule->rule_flag & PFRULE_RULESRCTRACK ||
rule->rpool.opts & PF_POOL_STICKYADDR)
k.rule.ptr = rule;
else
k.rule.ptr = NULL;
#ifdef __FreeBSD__
V_pf_status.scounters[SCNT_SRC_NODE_SEARCH]++;
*sn = RB_FIND(pf_src_tree, &V_tree_src_tracking, &k);
#else
pf_status.scounters[SCNT_SRC_NODE_SEARCH]++;
*sn = RB_FIND(pf_src_tree, &tree_src_tracking, &k);
#endif
}
if (*sn == NULL) {
if (!rule->max_src_nodes ||
rule->src_nodes < rule->max_src_nodes)
#ifdef __FreeBSD__
(*sn) = pool_get(&V_pf_src_tree_pl, PR_NOWAIT | PR_ZERO);
#else
(*sn) = pool_get(&pf_src_tree_pl, PR_NOWAIT | PR_ZERO);
#endif
else
#ifdef __FreeBSD__
V_pf_status.lcounters[LCNT_SRCNODES]++;
#else
pf_status.lcounters[LCNT_SRCNODES]++;
#endif
if ((*sn) == NULL)
return (-1);
pf_init_threshold(&(*sn)->conn_rate,
rule->max_src_conn_rate.limit,
rule->max_src_conn_rate.seconds);
(*sn)->af = af;
if (rule->rule_flag & PFRULE_RULESRCTRACK ||
rule->rpool.opts & PF_POOL_STICKYADDR)
(*sn)->rule.ptr = rule;
else
(*sn)->rule.ptr = NULL;
PF_ACPY(&(*sn)->addr, src, af);
if (RB_INSERT(pf_src_tree,
#ifdef __FreeBSD__
&V_tree_src_tracking, *sn) != NULL) {
if (V_pf_status.debug >= PF_DEBUG_MISC) {
#else
&tree_src_tracking, *sn) != NULL) {
if (pf_status.debug >= PF_DEBUG_MISC) {
#endif
printf("pf: src_tree insert failed: ");
pf_print_host(&(*sn)->addr, 0, af);
printf("\n");
}
#ifdef __FreeBSD__
pool_put(&V_pf_src_tree_pl, *sn);
#else
pool_put(&pf_src_tree_pl, *sn);
#endif
return (-1);
}
(*sn)->creation = time_second;
(*sn)->ruletype = rule->action;
if ((*sn)->rule.ptr != NULL)
(*sn)->rule.ptr->src_nodes++;
#ifdef __FreeBSD__
V_pf_status.scounters[SCNT_SRC_NODE_INSERT]++;
V_pf_status.src_nodes++;
#else
pf_status.scounters[SCNT_SRC_NODE_INSERT]++;
pf_status.src_nodes++;
#endif
} else {
if (rule->max_src_states &&
(*sn)->states >= rule->max_src_states) {
#ifdef __FreeBSD__
V_pf_status.lcounters[LCNT_SRCSTATES]++;
#else
pf_status.lcounters[LCNT_SRCSTATES]++;
#endif
return (-1);
}
}
return (0);
}
/* state table stuff */
static __inline int
pf_state_compare_key(struct pf_state_key *a, struct pf_state_key *b)
{
int diff;
if ((diff = a->proto - b->proto) != 0)
return (diff);
if ((diff = a->af - b->af) != 0)
return (diff);
switch (a->af) {
#ifdef INET
case AF_INET:
if (a->addr[0].addr32[0] > b->addr[0].addr32[0])
return (1);
if (a->addr[0].addr32[0] < b->addr[0].addr32[0])
return (-1);
if (a->addr[1].addr32[0] > b->addr[1].addr32[0])
return (1);
if (a->addr[1].addr32[0] < b->addr[1].addr32[0])
return (-1);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
if (a->addr[0].addr32[3] > b->addr[0].addr32[3])
return (1);
if (a->addr[0].addr32[3] < b->addr[0].addr32[3])
return (-1);
if (a->addr[1].addr32[3] > b->addr[1].addr32[3])
return (1);
if (a->addr[1].addr32[3] < b->addr[1].addr32[3])
return (-1);
if (a->addr[0].addr32[2] > b->addr[0].addr32[2])
return (1);
if (a->addr[0].addr32[2] < b->addr[0].addr32[2])
return (-1);
if (a->addr[1].addr32[2] > b->addr[1].addr32[2])
return (1);
if (a->addr[1].addr32[2] < b->addr[1].addr32[2])
return (-1);
if (a->addr[0].addr32[1] > b->addr[0].addr32[1])
return (1);
if (a->addr[0].addr32[1] < b->addr[0].addr32[1])
return (-1);
if (a->addr[1].addr32[1] > b->addr[1].addr32[1])
return (1);
if (a->addr[1].addr32[1] < b->addr[1].addr32[1])
return (-1);
if (a->addr[0].addr32[0] > b->addr[0].addr32[0])
return (1);
if (a->addr[0].addr32[0] < b->addr[0].addr32[0])
return (-1);
if (a->addr[1].addr32[0] > b->addr[1].addr32[0])
return (1);
if (a->addr[1].addr32[0] < b->addr[1].addr32[0])
return (-1);
break;
#endif /* INET6 */
}
if ((diff = a->port[0] - b->port[0]) != 0)
return (diff);
if ((diff = a->port[1] - b->port[1]) != 0)
return (diff);
return (0);
}
static __inline int
pf_state_compare_id(struct pf_state *a, struct pf_state *b)
{
if (a->id > b->id)
return (1);
if (a->id < b->id)
return (-1);
if (a->creatorid > b->creatorid)
return (1);
if (a->creatorid < b->creatorid)
return (-1);
return (0);
}
int
pf_state_key_attach(struct pf_state_key *sk, struct pf_state *s, int idx)
{
struct pf_state_item *si;
struct pf_state_key *cur;
struct pf_state *olds = NULL;
#ifdef __FreeBSD__
KASSERT(s->key[idx] == NULL, ("%s: key is null!", __FUNCTION__));
#else
KASSERT(s->key[idx] == NULL); /* XXX handle this? */
#endif
#ifdef __FreeBSD__
if ((cur = RB_INSERT(pf_state_tree, &V_pf_statetbl, sk)) != NULL) {
#else
if ((cur = RB_INSERT(pf_state_tree, &pf_statetbl, sk)) != NULL) {
#endif
/* key exists. check for same kif, if none, add to key */
TAILQ_FOREACH(si, &cur->states, entry)
if (si->s->kif == s->kif &&
si->s->direction == s->direction) {
if (sk->proto == IPPROTO_TCP &&
si->s->src.state >= TCPS_FIN_WAIT_2 &&
si->s->dst.state >= TCPS_FIN_WAIT_2) {
si->s->src.state = si->s->dst.state =
TCPS_CLOSED;
/* unlink late or sks can go away */
olds = si->s;
} else {
#ifdef __FreeBSD__
if (V_pf_status.debug >= PF_DEBUG_MISC) {
#else
if (pf_status.debug >= PF_DEBUG_MISC) {
#endif
printf("pf: %s key attach "
"failed on %s: ",
(idx == PF_SK_WIRE) ?
"wire" : "stack",
s->kif->pfik_name);
pf_print_state_parts(s,
(idx == PF_SK_WIRE) ?
sk : NULL,
(idx == PF_SK_STACK) ?
sk : NULL);
printf(", existing: ");
pf_print_state_parts(si->s,
(idx == PF_SK_WIRE) ?
sk : NULL,
(idx == PF_SK_STACK) ?
sk : NULL);
printf("\n");
}
#ifdef __FreeBSD__
pool_put(&V_pf_state_key_pl, sk);
#else
pool_put(&pf_state_key_pl, sk);
#endif
return (-1); /* collision! */
}
}
#ifdef __FreeBSD__
pool_put(&V_pf_state_key_pl, sk);
#else
pool_put(&pf_state_key_pl, sk);
#endif
s->key[idx] = cur;
} else
s->key[idx] = sk;
#ifdef __FreeBSD__
if ((si = pool_get(&V_pf_state_item_pl, PR_NOWAIT)) == NULL) {
#else
if ((si = pool_get(&pf_state_item_pl, PR_NOWAIT)) == NULL) {
#endif
pf_state_key_detach(s, idx);
return (-1);
}
si->s = s;
/* list is sorted, if-bound states before floating */
#ifdef __FreeBSD__
if (s->kif == V_pfi_all)
#else
if (s->kif == pfi_all)
#endif
TAILQ_INSERT_TAIL(&s->key[idx]->states, si, entry);
else
TAILQ_INSERT_HEAD(&s->key[idx]->states, si, entry);
if (olds)
pf_unlink_state(olds);
return (0);
}
void
pf_detach_state(struct pf_state *s)
{
if (s->key[PF_SK_WIRE] == s->key[PF_SK_STACK])
s->key[PF_SK_WIRE] = NULL;
if (s->key[PF_SK_STACK] != NULL)
pf_state_key_detach(s, PF_SK_STACK);
if (s->key[PF_SK_WIRE] != NULL)
pf_state_key_detach(s, PF_SK_WIRE);
}
void
pf_state_key_detach(struct pf_state *s, int idx)
{
struct pf_state_item *si;
si = TAILQ_FIRST(&s->key[idx]->states);
while (si && si->s != s)
si = TAILQ_NEXT(si, entry);
if (si) {
TAILQ_REMOVE(&s->key[idx]->states, si, entry);
#ifdef __FreeBSD__
pool_put(&V_pf_state_item_pl, si);
#else
pool_put(&pf_state_item_pl, si);
#endif
}
if (TAILQ_EMPTY(&s->key[idx]->states)) {
#ifdef __FreeBSD__
RB_REMOVE(pf_state_tree, &V_pf_statetbl, s->key[idx]);
#else
RB_REMOVE(pf_state_tree, &pf_statetbl, s->key[idx]);
#endif
if (s->key[idx]->reverse)
s->key[idx]->reverse->reverse = NULL;
#ifdef __FreeBSD__
/* XXX: implement this */
#else
if (s->key[idx]->inp)
s->key[idx]->inp->inp_pf_sk = NULL;
#endif
#ifdef __FreeBSD__
pool_put(&V_pf_state_key_pl, s->key[idx]);
#else
pool_put(&pf_state_key_pl, s->key[idx]);
#endif
}
s->key[idx] = NULL;
}
struct pf_state_key *
pf_alloc_state_key(int pool_flags)
{
struct pf_state_key *sk;
#ifdef __FreeBSD__
if ((sk = pool_get(&V_pf_state_key_pl, pool_flags)) == NULL)
#else
if ((sk = pool_get(&pf_state_key_pl, pool_flags)) == NULL)
#endif
return (NULL);
TAILQ_INIT(&sk->states);
return (sk);
}
int
pf_state_key_setup(struct pf_pdesc *pd, struct pf_rule *nr,
struct pf_state_key **skw, struct pf_state_key **sks,
struct pf_state_key **skp, struct pf_state_key **nkp,
struct pf_addr *saddr, struct pf_addr *daddr,
u_int16_t sport, u_int16_t dport)
{
#ifdef __FreeBSD__
KASSERT((*skp == NULL && *nkp == NULL),
("%s: skp == NULL && nkp == NULL", __FUNCTION__));
#else
KASSERT((*skp == NULL && *nkp == NULL));
#endif
if ((*skp = pf_alloc_state_key(PR_NOWAIT | PR_ZERO)) == NULL)
return (ENOMEM);
PF_ACPY(&(*skp)->addr[pd->sidx], saddr, pd->af);
PF_ACPY(&(*skp)->addr[pd->didx], daddr, pd->af);
(*skp)->port[pd->sidx] = sport;
(*skp)->port[pd->didx] = dport;
(*skp)->proto = pd->proto;
(*skp)->af = pd->af;
if (nr != NULL) {
if ((*nkp = pf_alloc_state_key(PR_NOWAIT | PR_ZERO)) == NULL)
return (ENOMEM); /* caller must handle cleanup */
/* XXX maybe just bcopy and TAILQ_INIT(&(*nkp)->states) */
PF_ACPY(&(*nkp)->addr[0], &(*skp)->addr[0], pd->af);
PF_ACPY(&(*nkp)->addr[1], &(*skp)->addr[1], pd->af);
(*nkp)->port[0] = (*skp)->port[0];
(*nkp)->port[1] = (*skp)->port[1];
(*nkp)->proto = pd->proto;
(*nkp)->af = pd->af;
} else
*nkp = *skp;
if (pd->dir == PF_IN) {
*skw = *skp;
*sks = *nkp;
} else {
*sks = *skp;
*skw = *nkp;
}
return (0);
}
int
pf_state_insert(struct pfi_kif *kif, struct pf_state_key *skw,
struct pf_state_key *sks, struct pf_state *s)
{
#ifndef __FreeBSD__
splassert(IPL_SOFTNET);
#endif
s->kif = kif;
if (skw == sks) {
if (pf_state_key_attach(skw, s, PF_SK_WIRE))
return (-1);
s->key[PF_SK_STACK] = s->key[PF_SK_WIRE];
} else {
if (pf_state_key_attach(skw, s, PF_SK_WIRE)) {
#ifdef __FreeBSD__
pool_put(&V_pf_state_key_pl, sks);
#else
pool_put(&pf_state_key_pl, sks);
#endif
return (-1);
}
if (pf_state_key_attach(sks, s, PF_SK_STACK)) {
pf_state_key_detach(s, PF_SK_WIRE);
return (-1);
}
}
if (s->id == 0 && s->creatorid == 0) {
#ifdef __FreeBSD__
s->id = htobe64(V_pf_status.stateid++);
s->creatorid = V_pf_status.hostid;
#else
s->id = htobe64(pf_status.stateid++);
s->creatorid = pf_status.hostid;
#endif
}
#ifdef __FreeBSD__
if (RB_INSERT(pf_state_tree_id, &V_tree_id, s) != NULL) {
if (V_pf_status.debug >= PF_DEBUG_MISC) {
#else
if (RB_INSERT(pf_state_tree_id, &tree_id, s) != NULL) {
if (pf_status.debug >= PF_DEBUG_MISC) {
#endif
printf("pf: state insert failed: "
"id: %016llx creatorid: %08x",
#ifdef __FreeBSD__
(unsigned long long)betoh64(s->id), ntohl(s->creatorid));
#else
betoh64(s->id), ntohl(s->creatorid));
#endif
printf("\n");
}
pf_detach_state(s);
return (-1);
}
#ifdef __FreeBSD__
TAILQ_INSERT_TAIL(&V_state_list, s, entry_list);
V_pf_status.fcounters[FCNT_STATE_INSERT]++;
V_pf_status.states++;
#else
TAILQ_INSERT_TAIL(&state_list, s, entry_list);
pf_status.fcounters[FCNT_STATE_INSERT]++;
pf_status.states++;
#endif
pfi_kif_ref(kif, PFI_KIF_REF_STATE);
#if NPFSYNC > 0
#ifdef __FreeBSD__
if (pfsync_insert_state_ptr != NULL)
pfsync_insert_state_ptr(s);
#else
pfsync_insert_state(s);
#endif
#endif
return (0);
}
struct pf_state *
pf_find_state_byid(struct pf_state_cmp *key)
{
#ifdef __FreeBSD__
V_pf_status.fcounters[FCNT_STATE_SEARCH]++;
return (RB_FIND(pf_state_tree_id, &V_tree_id, (struct pf_state *)key));
#else
pf_status.fcounters[FCNT_STATE_SEARCH]++;
return (RB_FIND(pf_state_tree_id, &tree_id, (struct pf_state *)key));
#endif
}
/* XXX debug function, intended to be removed one day */
int
pf_compare_state_keys(struct pf_state_key *a, struct pf_state_key *b,
struct pfi_kif *kif, u_int dir)
{
/* a (from hdr) and b (new) must be exact opposites of each other */
if (a->af == b->af && a->proto == b->proto &&
PF_AEQ(&a->addr[0], &b->addr[1], a->af) &&
PF_AEQ(&a->addr[1], &b->addr[0], a->af) &&
a->port[0] == b->port[1] &&
a->port[1] == b->port[0])
return (0);
else {
/* mismatch. must not happen. */
printf("pf: state key linking mismatch! dir=%s, "
"if=%s, stored af=%u, a0: ",
dir == PF_OUT ? "OUT" : "IN", kif->pfik_name, a->af);
pf_print_host(&a->addr[0], a->port[0], a->af);
printf(", a1: ");
pf_print_host(&a->addr[1], a->port[1], a->af);
printf(", proto=%u", a->proto);
printf(", found af=%u, a0: ", b->af);
pf_print_host(&b->addr[0], b->port[0], b->af);
printf(", a1: ");
pf_print_host(&b->addr[1], b->port[1], b->af);
printf(", proto=%u", b->proto);
printf(".\n");
return (-1);
}
}
struct pf_state *
#ifdef __FreeBSD__
pf_find_state(struct pfi_kif *kif, struct pf_state_key_cmp *key, u_int dir,
struct mbuf *m, struct pf_mtag *pftag)
#else
pf_find_state(struct pfi_kif *kif, struct pf_state_key_cmp *key, u_int dir,
struct mbuf *m)
#endif
{
struct pf_state_key *sk;
struct pf_state_item *si;
#ifdef __FreeBSD__
V_pf_status.fcounters[FCNT_STATE_SEARCH]++;
#else
pf_status.fcounters[FCNT_STATE_SEARCH]++;
#endif
#ifdef __FreeBSD__
if (dir == PF_OUT && pftag->statekey &&
((struct pf_state_key *)pftag->statekey)->reverse)
sk = ((struct pf_state_key *)pftag->statekey)->reverse;
else {
#ifdef __FreeBSD__
if ((sk = RB_FIND(pf_state_tree, &V_pf_statetbl,
#else
if ((sk = RB_FIND(pf_state_tree, &pf_statetbl,
#endif
(struct pf_state_key *)key)) == NULL)
return (NULL);
if (dir == PF_OUT && pftag->statekey &&
pf_compare_state_keys(pftag->statekey, sk,
kif, dir) == 0) {
((struct pf_state_key *)
pftag->statekey)->reverse = sk;
sk->reverse = pftag->statekey;
}
}
#else
if (dir == PF_OUT && m->m_pkthdr.pf.statekey &&
((struct pf_state_key *)m->m_pkthdr.pf.statekey)->reverse)
sk = ((struct pf_state_key *)m->m_pkthdr.pf.statekey)->reverse;
else {
#ifdef __FreeBSD__
if ((sk = RB_FIND(pf_state_tree, &V_pf_statetbl,
#else
if ((sk = RB_FIND(pf_state_tree, &pf_statetbl,
#endif
(struct pf_state_key *)key)) == NULL)
return (NULL);
if (dir == PF_OUT && m->m_pkthdr.pf.statekey &&
pf_compare_state_keys(m->m_pkthdr.pf.statekey, sk,
kif, dir) == 0) {
((struct pf_state_key *)
m->m_pkthdr.pf.statekey)->reverse = sk;
sk->reverse = m->m_pkthdr.pf.statekey;
}
}
#endif
if (dir == PF_OUT)
#ifdef __FreeBSD__
pftag->statekey = NULL;
#else
m->m_pkthdr.pf.statekey = NULL;
#endif
/* list is sorted, if-bound states before floating ones */
TAILQ_FOREACH(si, &sk->states, entry)
#ifdef __FreeBSD__
if ((si->s->kif == V_pfi_all || si->s->kif == kif) &&
#else
if ((si->s->kif == pfi_all || si->s->kif == kif) &&
#endif
sk == (dir == PF_IN ? si->s->key[PF_SK_WIRE] :
si->s->key[PF_SK_STACK]))
return (si->s);
return (NULL);
}
struct pf_state *
pf_find_state_all(struct pf_state_key_cmp *key, u_int dir, int *more)
{
struct pf_state_key *sk;
struct pf_state_item *si, *ret = NULL;
#ifdef __FreeBSD__
V_pf_status.fcounters[FCNT_STATE_SEARCH]++;
#else
pf_status.fcounters[FCNT_STATE_SEARCH]++;
#endif
#ifdef __FreeBSD__
sk = RB_FIND(pf_state_tree, &V_pf_statetbl, (struct pf_state_key *)key);
#else
sk = RB_FIND(pf_state_tree, &pf_statetbl, (struct pf_state_key *)key);
#endif
if (sk != NULL) {
TAILQ_FOREACH(si, &sk->states, entry)
if (dir == PF_INOUT ||
(sk == (dir == PF_IN ? si->s->key[PF_SK_WIRE] :
si->s->key[PF_SK_STACK]))) {
if (more == NULL)
return (si->s);
if (ret)
(*more)++;
else
ret = si;
}
}
return (ret ? ret->s : NULL);
}
/* END state table stuff */
void
pf_purge_thread(void *v)
{
int nloops = 0, s;
#ifdef __FreeBSD__
int locked;
#endif
CURVNET_SET((struct vnet *)v);
for (;;) {
tsleep(pf_purge_thread, PWAIT, "pftm", 1 * hz);
#ifdef __FreeBSD__
sx_slock(&V_pf_consistency_lock);
PF_LOCK();
locked = 0;
if (V_pf_end_threads) {
PF_UNLOCK();
sx_sunlock(&V_pf_consistency_lock);
sx_xlock(&V_pf_consistency_lock);
PF_LOCK();
pf_purge_expired_states(V_pf_status.states, 1);
pf_purge_expired_fragments();
pf_purge_expired_src_nodes(1);
V_pf_end_threads++;
sx_xunlock(&V_pf_consistency_lock);
PF_UNLOCK();
wakeup(pf_purge_thread);
kproc_exit(0);
}
#endif
s = splsoftnet();
/* process a fraction of the state table every second */
#ifdef __FreeBSD__
if (!pf_purge_expired_states(1 + (V_pf_status.states /
V_pf_default_rule.timeout[PFTM_INTERVAL]), 0)) {
PF_UNLOCK();
sx_sunlock(&V_pf_consistency_lock);
sx_xlock(&V_pf_consistency_lock);
PF_LOCK();
locked = 1;
pf_purge_expired_states(1 + (V_pf_status.states /
V_pf_default_rule.timeout[PFTM_INTERVAL]), 1);
}
#else
pf_purge_expired_states(1 + (pf_status.states
/ pf_default_rule.timeout[PFTM_INTERVAL]));
#endif
/* purge other expired types every PFTM_INTERVAL seconds */
#ifdef __FreeBSD__
if (++nloops >= V_pf_default_rule.timeout[PFTM_INTERVAL]) {
#else
if (++nloops >= pf_default_rule.timeout[PFTM_INTERVAL]) {
#endif
pf_purge_expired_fragments();
pf_purge_expired_src_nodes(0);
nloops = 0;
}
splx(s);
#ifdef __FreeBSD__
PF_UNLOCK();
if (locked)
sx_xunlock(&V_pf_consistency_lock);
else
sx_sunlock(&V_pf_consistency_lock);
#endif
}
CURVNET_RESTORE();
}
u_int32_t
pf_state_expires(const struct pf_state *state)
{
u_int32_t timeout;
u_int32_t start;
u_int32_t end;
u_int32_t states;
/* handle all PFTM_* > PFTM_MAX here */
if (state->timeout == PFTM_PURGE)
return (time_second);
if (state->timeout == PFTM_UNTIL_PACKET)
return (0);
#ifdef __FreeBSD__
KASSERT(state->timeout != PFTM_UNLINKED,
("pf_state_expires: timeout == PFTM_UNLINKED"));
KASSERT((state->timeout < PFTM_MAX),
("pf_state_expires: timeout > PFTM_MAX"));
#else
KASSERT(state->timeout != PFTM_UNLINKED);
KASSERT(state->timeout < PFTM_MAX);
#endif
timeout = state->rule.ptr->timeout[state->timeout];
if (!timeout)
#ifdef __FreeBSD__
timeout = V_pf_default_rule.timeout[state->timeout];
#else
timeout = pf_default_rule.timeout[state->timeout];
#endif
start = state->rule.ptr->timeout[PFTM_ADAPTIVE_START];
if (start) {
end = state->rule.ptr->timeout[PFTM_ADAPTIVE_END];
states = state->rule.ptr->states_cur;
} else {
#ifdef __FreeBSD__
start = V_pf_default_rule.timeout[PFTM_ADAPTIVE_START];
end = V_pf_default_rule.timeout[PFTM_ADAPTIVE_END];
states = V_pf_status.states;
#else
start = pf_default_rule.timeout[PFTM_ADAPTIVE_START];
end = pf_default_rule.timeout[PFTM_ADAPTIVE_END];
states = pf_status.states;
#endif
}
if (end && states > start && start < end) {
if (states < end)
return (state->expire + timeout * (end - states) /
(end - start));
else
return (time_second);
}
return (state->expire + timeout);
}
#ifdef __FreeBSD__
int
pf_purge_expired_src_nodes(int waslocked)
#else
void
pf_purge_expired_src_nodes(int waslocked)
#endif
{
struct pf_src_node *cur, *next;
int locked = waslocked;
#ifdef __FreeBSD__
for (cur = RB_MIN(pf_src_tree, &V_tree_src_tracking); cur; cur = next) {
next = RB_NEXT(pf_src_tree, &V_tree_src_tracking, cur);
#else
for (cur = RB_MIN(pf_src_tree, &tree_src_tracking); cur; cur = next) {
next = RB_NEXT(pf_src_tree, &tree_src_tracking, cur);
#endif
if (cur->states <= 0 && cur->expire <= time_second) {
if (! locked) {
#ifdef __FreeBSD__
if (!sx_try_upgrade(&V_pf_consistency_lock))
return (0);
#else
rw_enter_write(&pf_consistency_lock);
#endif
next = RB_NEXT(pf_src_tree,
#ifdef __FreeBSD__
&V_tree_src_tracking, cur);
#else
&tree_src_tracking, cur);
#endif
locked = 1;
}
if (cur->rule.ptr != NULL) {
cur->rule.ptr->src_nodes--;
if (cur->rule.ptr->states_cur <= 0 &&
cur->rule.ptr->max_src_nodes <= 0)
pf_rm_rule(NULL, cur->rule.ptr);
}
#ifdef __FreeBSD__
RB_REMOVE(pf_src_tree, &V_tree_src_tracking, cur);
V_pf_status.scounters[SCNT_SRC_NODE_REMOVALS]++;
V_pf_status.src_nodes--;
pool_put(&V_pf_src_tree_pl, cur);
#else
RB_REMOVE(pf_src_tree, &tree_src_tracking, cur);
pf_status.scounters[SCNT_SRC_NODE_REMOVALS]++;
pf_status.src_nodes--;
pool_put(&pf_src_tree_pl, cur);
#endif
}
}
if (locked && !waslocked)
#ifdef __FreeBSD__
{
sx_downgrade(&V_pf_consistency_lock);
}
return (1);
#else
rw_exit_write(&pf_consistency_lock);
#endif
}
void
pf_src_tree_remove_state(struct pf_state *s)
{
u_int32_t timeout;
if (s->src_node != NULL) {
if (s->src.tcp_est)
--s->src_node->conn;
if (--s->src_node->states <= 0) {
timeout = s->rule.ptr->timeout[PFTM_SRC_NODE];
if (!timeout)
timeout =
#ifdef __FreeBSD__
V_pf_default_rule.timeout[PFTM_SRC_NODE];
#else
pf_default_rule.timeout[PFTM_SRC_NODE];
#endif
s->src_node->expire = time_second + timeout;
}
}
if (s->nat_src_node != s->src_node && s->nat_src_node != NULL) {
if (--s->nat_src_node->states <= 0) {
timeout = s->rule.ptr->timeout[PFTM_SRC_NODE];
if (!timeout)
timeout =
#ifdef __FreeBSD__
V_pf_default_rule.timeout[PFTM_SRC_NODE];
#else
pf_default_rule.timeout[PFTM_SRC_NODE];
#endif
s->nat_src_node->expire = time_second + timeout;
}
}
s->src_node = s->nat_src_node = NULL;
}
/* callers should be at splsoftnet */
void
pf_unlink_state(struct pf_state *cur)
{
#ifdef __FreeBSD__
if (cur->local_flags & PFSTATE_EXPIRING)
return;
cur->local_flags |= PFSTATE_EXPIRING;
#else
splassert(IPL_SOFTNET);
#endif
if (cur->src.state == PF_TCPS_PROXY_DST) {
/* XXX wire key the right one? */
#ifdef __FreeBSD__
pf_send_tcp(NULL, cur->rule.ptr, cur->key[PF_SK_WIRE]->af,
#else
pf_send_tcp(cur->rule.ptr, cur->key[PF_SK_WIRE]->af,
#endif
&cur->key[PF_SK_WIRE]->addr[1],
&cur->key[PF_SK_WIRE]->addr[0],
cur->key[PF_SK_WIRE]->port[1],
cur->key[PF_SK_WIRE]->port[0],
cur->src.seqhi, cur->src.seqlo + 1,
TH_RST|TH_ACK, 0, 0, 0, 1, cur->tag, NULL, NULL);
}
#ifdef __FreeBSD__
RB_REMOVE(pf_state_tree_id, &V_tree_id, cur);
#else
RB_REMOVE(pf_state_tree_id, &tree_id, cur);
#endif
#if NPFLOW > 0
if (cur->state_flags & PFSTATE_PFLOW)
#ifdef __FreeBSD__
if (export_pflow_ptr != NULL)
export_pflow_ptr(cur);
#else
export_pflow(cur);
#endif
#endif
#if NPFSYNC > 0
#ifdef __FreeBSD__
if (pfsync_delete_state_ptr != NULL)
pfsync_delete_state_ptr(cur);
#else
pfsync_delete_state(cur);
#endif
#endif
cur->timeout = PFTM_UNLINKED;
pf_src_tree_remove_state(cur);
pf_detach_state(cur);
}
/* callers should be at splsoftnet and hold the
* write_lock on pf_consistency_lock */
void
pf_free_state(struct pf_state *cur)
{
#ifndef __FreeBSD__
splassert(IPL_SOFTNET);
#endif
#if NPFSYNC > 0
#ifdef __FreeBSD__
if (pfsync_state_in_use_ptr != NULL)
pfsync_state_in_use_ptr(cur);
#else
if (pfsync_state_in_use(cur))
#endif
return;
#endif
#ifdef __FreeBSD__
KASSERT(cur->timeout == PFTM_UNLINKED,
("pf_free_state: cur->timeout != PFTM_UNLINKED"));
#else
KASSERT(cur->timeout == PFTM_UNLINKED);
#endif
if (--cur->rule.ptr->states_cur <= 0 &&
cur->rule.ptr->src_nodes <= 0)
pf_rm_rule(NULL, cur->rule.ptr);
if (cur->nat_rule.ptr != NULL)
if (--cur->nat_rule.ptr->states_cur <= 0 &&
cur->nat_rule.ptr->src_nodes <= 0)
pf_rm_rule(NULL, cur->nat_rule.ptr);
if (cur->anchor.ptr != NULL)
if (--cur->anchor.ptr->states_cur <= 0)
pf_rm_rule(NULL, cur->anchor.ptr);
pf_normalize_tcp_cleanup(cur);
pfi_kif_unref(cur->kif, PFI_KIF_REF_STATE);
#ifdef __FreeBSD__
TAILQ_REMOVE(&V_state_list, cur, entry_list);
#else
TAILQ_REMOVE(&state_list, cur, entry_list);
#endif
if (cur->tag)
pf_tag_unref(cur->tag);
#ifdef __FreeBSD__
pool_put(&V_pf_state_pl, cur);
V_pf_status.fcounters[FCNT_STATE_REMOVALS]++;
V_pf_status.states--;
#else
pool_put(&pf_state_pl, cur);
pf_status.fcounters[FCNT_STATE_REMOVALS]++;
pf_status.states--;
#endif
}
#ifdef __FreeBSD__
int
pf_purge_expired_states(u_int32_t maxcheck, int waslocked)
#else
void
pf_purge_expired_states(u_int32_t maxcheck)
#endif
{
static struct pf_state *cur = NULL;
struct pf_state *next;
#ifdef __FreeBSD__
int locked = waslocked;
#else
int locked = 0;
#endif
while (maxcheck--) {
/* wrap to start of list when we hit the end */
if (cur == NULL) {
#ifdef __FreeBSD__
cur = TAILQ_FIRST(&V_state_list);
#else
cur = TAILQ_FIRST(&state_list);
#endif
if (cur == NULL)
break; /* list empty */
}
/* get next state, as cur may get deleted */
next = TAILQ_NEXT(cur, entry_list);
if (cur->timeout == PFTM_UNLINKED) {
/* free unlinked state */
if (! locked) {
#ifdef __FreeBSD__
if (!sx_try_upgrade(&V_pf_consistency_lock))
return (0);
#else
rw_enter_write(&pf_consistency_lock);
#endif
locked = 1;
}
pf_free_state(cur);
} else if (pf_state_expires(cur) <= time_second) {
/* unlink and free expired state */
pf_unlink_state(cur);
if (! locked) {
#ifdef __FreeBSD__
if (!sx_try_upgrade(&V_pf_consistency_lock))
return (0);
#else
rw_enter_write(&pf_consistency_lock);
#endif
locked = 1;
}
pf_free_state(cur);
}
cur = next;
}
#ifdef __FreeBSD__
if (!waslocked && locked)
sx_downgrade(&V_pf_consistency_lock);
return (1);
#else
if (locked)
rw_exit_write(&pf_consistency_lock);
#endif
}
int
pf_tbladdr_setup(struct pf_ruleset *rs, struct pf_addr_wrap *aw)
{
if (aw->type != PF_ADDR_TABLE)
return (0);
if ((aw->p.tbl = pfr_attach_table(rs, aw->v.tblname, 1)) == NULL)
return (1);
return (0);
}
void
pf_tbladdr_remove(struct pf_addr_wrap *aw)
{
if (aw->type != PF_ADDR_TABLE || aw->p.tbl == NULL)
return;
pfr_detach_table(aw->p.tbl);
aw->p.tbl = NULL;
}
void
pf_tbladdr_copyout(struct pf_addr_wrap *aw)
{
struct pfr_ktable *kt = aw->p.tbl;
if (aw->type != PF_ADDR_TABLE || kt == NULL)
return;
if (!(kt->pfrkt_flags & PFR_TFLAG_ACTIVE) && kt->pfrkt_root != NULL)
kt = kt->pfrkt_root;
aw->p.tbl = NULL;
aw->p.tblcnt = (kt->pfrkt_flags & PFR_TFLAG_ACTIVE) ?
kt->pfrkt_cnt : -1;
}
void
pf_print_host(struct pf_addr *addr, u_int16_t p, sa_family_t af)
{
switch (af) {
#ifdef INET
case AF_INET: {
u_int32_t a = ntohl(addr->addr32[0]);
printf("%u.%u.%u.%u", (a>>24)&255, (a>>16)&255,
(a>>8)&255, a&255);
if (p) {
p = ntohs(p);
printf(":%u", p);
}
break;
}
#endif /* INET */
#ifdef INET6
case AF_INET6: {
u_int16_t b;
u_int8_t i, curstart, curend, maxstart, maxend;
curstart = curend = maxstart = maxend = 255;
for (i = 0; i < 8; i++) {
if (!addr->addr16[i]) {
if (curstart == 255)
curstart = i;
curend = i;
} else {
if ((curend - curstart) >
(maxend - maxstart)) {
maxstart = curstart;
maxend = curend;
}
curstart = curend = 255;
}
}
if ((curend - curstart) >
(maxend - maxstart)) {
maxstart = curstart;
maxend = curend;
}
for (i = 0; i < 8; i++) {
if (i >= maxstart && i <= maxend) {
if (i == 0)
printf(":");
if (i == maxend)
printf(":");
} else {
b = ntohs(addr->addr16[i]);
printf("%x", b);
if (i < 7)
printf(":");
}
}
if (p) {
p = ntohs(p);
printf("[%u]", p);
}
break;
}
#endif /* INET6 */
}
}
void
pf_print_state(struct pf_state *s)
{
pf_print_state_parts(s, NULL, NULL);
}
void
pf_print_state_parts(struct pf_state *s,
struct pf_state_key *skwp, struct pf_state_key *sksp)
{
struct pf_state_key *skw, *sks;
u_int8_t proto, dir;
/* Do our best to fill these, but they're skipped if NULL */
skw = skwp ? skwp : (s ? s->key[PF_SK_WIRE] : NULL);
sks = sksp ? sksp : (s ? s->key[PF_SK_STACK] : NULL);
proto = skw ? skw->proto : (sks ? sks->proto : 0);
dir = s ? s->direction : 0;
switch (proto) {
case IPPROTO_IPV4:
printf("IPv4");
break;
case IPPROTO_IPV6:
printf("IPv6");
break;
case IPPROTO_TCP:
printf("TCP");
break;
case IPPROTO_UDP:
printf("UDP");
break;
case IPPROTO_ICMP:
printf("ICMP");
break;
case IPPROTO_ICMPV6:
printf("ICMPv6");
break;
default:
printf("%u", skw->proto);
break;
}
switch (dir) {
case PF_IN:
printf(" in");
break;
case PF_OUT:
printf(" out");
break;
}
if (skw) {
printf(" wire: ");
pf_print_host(&skw->addr[0], skw->port[0], skw->af);
printf(" ");
pf_print_host(&skw->addr[1], skw->port[1], skw->af);
}
if (sks) {
printf(" stack: ");
if (sks != skw) {
pf_print_host(&sks->addr[0], sks->port[0], sks->af);
printf(" ");
pf_print_host(&sks->addr[1], sks->port[1], sks->af);
} else
printf("-");
}
if (s) {
if (proto == IPPROTO_TCP) {
printf(" [lo=%u high=%u win=%u modulator=%u",
s->src.seqlo, s->src.seqhi,
s->src.max_win, s->src.seqdiff);
if (s->src.wscale && s->dst.wscale)
printf(" wscale=%u",
s->src.wscale & PF_WSCALE_MASK);
printf("]");
printf(" [lo=%u high=%u win=%u modulator=%u",
s->dst.seqlo, s->dst.seqhi,
s->dst.max_win, s->dst.seqdiff);
if (s->src.wscale && s->dst.wscale)
printf(" wscale=%u",
s->dst.wscale & PF_WSCALE_MASK);
printf("]");
}
printf(" %u:%u", s->src.state, s->dst.state);
}
}
void
pf_print_flags(u_int8_t f)
{
if (f)
printf(" ");
if (f & TH_FIN)
printf("F");
if (f & TH_SYN)
printf("S");
if (f & TH_RST)
printf("R");
if (f & TH_PUSH)
printf("P");
if (f & TH_ACK)
printf("A");
if (f & TH_URG)
printf("U");
if (f & TH_ECE)
printf("E");
if (f & TH_CWR)
printf("W");
}
#define PF_SET_SKIP_STEPS(i) \
do { \
while (head[i] != cur) { \
head[i]->skip[i].ptr = cur; \
head[i] = TAILQ_NEXT(head[i], entries); \
} \
} while (0)
void
pf_calc_skip_steps(struct pf_rulequeue *rules)
{
struct pf_rule *cur, *prev, *head[PF_SKIP_COUNT];
int i;
cur = TAILQ_FIRST(rules);
prev = cur;
for (i = 0; i < PF_SKIP_COUNT; ++i)
head[i] = cur;
while (cur != NULL) {
if (cur->kif != prev->kif || cur->ifnot != prev->ifnot)
PF_SET_SKIP_STEPS(PF_SKIP_IFP);
if (cur->direction != prev->direction)
PF_SET_SKIP_STEPS(PF_SKIP_DIR);
if (cur->af != prev->af)
PF_SET_SKIP_STEPS(PF_SKIP_AF);
if (cur->proto != prev->proto)
PF_SET_SKIP_STEPS(PF_SKIP_PROTO);
if (cur->src.neg != prev->src.neg ||
pf_addr_wrap_neq(&cur->src.addr, &prev->src.addr))
PF_SET_SKIP_STEPS(PF_SKIP_SRC_ADDR);
if (cur->src.port[0] != prev->src.port[0] ||
cur->src.port[1] != prev->src.port[1] ||
cur->src.port_op != prev->src.port_op)
PF_SET_SKIP_STEPS(PF_SKIP_SRC_PORT);
if (cur->dst.neg != prev->dst.neg ||
pf_addr_wrap_neq(&cur->dst.addr, &prev->dst.addr))
PF_SET_SKIP_STEPS(PF_SKIP_DST_ADDR);
if (cur->dst.port[0] != prev->dst.port[0] ||
cur->dst.port[1] != prev->dst.port[1] ||
cur->dst.port_op != prev->dst.port_op)
PF_SET_SKIP_STEPS(PF_SKIP_DST_PORT);
prev = cur;
cur = TAILQ_NEXT(cur, entries);
}
for (i = 0; i < PF_SKIP_COUNT; ++i)
PF_SET_SKIP_STEPS(i);
}
int
pf_addr_wrap_neq(struct pf_addr_wrap *aw1, struct pf_addr_wrap *aw2)
{
if (aw1->type != aw2->type)
return (1);
switch (aw1->type) {
case PF_ADDR_ADDRMASK:
case PF_ADDR_RANGE:
if (PF_ANEQ(&aw1->v.a.addr, &aw2->v.a.addr, 0))
return (1);
if (PF_ANEQ(&aw1->v.a.mask, &aw2->v.a.mask, 0))
return (1);
return (0);
case PF_ADDR_DYNIFTL:
return (aw1->p.dyn->pfid_kt != aw2->p.dyn->pfid_kt);
case PF_ADDR_NOROUTE:
case PF_ADDR_URPFFAILED:
return (0);
case PF_ADDR_TABLE:
return (aw1->p.tbl != aw2->p.tbl);
case PF_ADDR_RTLABEL:
return (aw1->v.rtlabel != aw2->v.rtlabel);
default:
printf("invalid address type: %d\n", aw1->type);
return (1);
}
}
u_int16_t
pf_cksum_fixup(u_int16_t cksum, u_int16_t old, u_int16_t new, u_int8_t udp)
{
u_int32_t l;
if (udp && !cksum)
return (0x0000);
l = cksum + old - new;
l = (l >> 16) + (l & 65535);
l = l & 65535;
if (udp && !l)
return (0xFFFF);
return (l);
}
void
pf_change_ap(struct pf_addr *a, u_int16_t *p, u_int16_t *ic, u_int16_t *pc,
struct pf_addr *an, u_int16_t pn, u_int8_t u, sa_family_t af)
{
struct pf_addr ao;
u_int16_t po = *p;
PF_ACPY(&ao, a, af);
PF_ACPY(a, an, af);
*p = pn;
switch (af) {
#ifdef INET
case AF_INET:
*ic = pf_cksum_fixup(pf_cksum_fixup(*ic,
ao.addr16[0], an->addr16[0], 0),
ao.addr16[1], an->addr16[1], 0);
*p = pn;
*pc = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(*pc,
ao.addr16[0], an->addr16[0], u),
ao.addr16[1], an->addr16[1], u),
po, pn, u);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
*pc = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(*pc,
ao.addr16[0], an->addr16[0], u),
ao.addr16[1], an->addr16[1], u),
ao.addr16[2], an->addr16[2], u),
ao.addr16[3], an->addr16[3], u),
ao.addr16[4], an->addr16[4], u),
ao.addr16[5], an->addr16[5], u),
ao.addr16[6], an->addr16[6], u),
ao.addr16[7], an->addr16[7], u),
po, pn, u);
break;
#endif /* INET6 */
}
}
/* Changes a u_int32_t. Uses a void * so there are no align restrictions */
void
pf_change_a(void *a, u_int16_t *c, u_int32_t an, u_int8_t u)
{
u_int32_t ao;
memcpy(&ao, a, sizeof(ao));
memcpy(a, &an, sizeof(u_int32_t));
*c = pf_cksum_fixup(pf_cksum_fixup(*c, ao / 65536, an / 65536, u),
ao % 65536, an % 65536, u);
}
#ifdef INET6
void
pf_change_a6(struct pf_addr *a, u_int16_t *c, struct pf_addr *an, u_int8_t u)
{
struct pf_addr ao;
PF_ACPY(&ao, a, AF_INET6);
PF_ACPY(a, an, AF_INET6);
*c = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
pf_cksum_fixup(pf_cksum_fixup(*c,
ao.addr16[0], an->addr16[0], u),
ao.addr16[1], an->addr16[1], u),
ao.addr16[2], an->addr16[2], u),
ao.addr16[3], an->addr16[3], u),
ao.addr16[4], an->addr16[4], u),
ao.addr16[5], an->addr16[5], u),
ao.addr16[6], an->addr16[6], u),
ao.addr16[7], an->addr16[7], u);
}
#endif /* INET6 */
void
pf_change_icmp(struct pf_addr *ia, u_int16_t *ip, struct pf_addr *oa,
struct pf_addr *na, u_int16_t np, u_int16_t *pc, u_int16_t *h2c,
u_int16_t *ic, u_int16_t *hc, u_int8_t u, sa_family_t af)
{
struct pf_addr oia, ooa;
PF_ACPY(&oia, ia, af);
if (oa)
PF_ACPY(&ooa, oa, af);
/* Change inner protocol port, fix inner protocol checksum. */
if (ip != NULL) {
u_int16_t oip = *ip;
u_int32_t opc;
if (pc != NULL)
opc = *pc;
*ip = np;
if (pc != NULL)
*pc = pf_cksum_fixup(*pc, oip, *ip, u);
*ic = pf_cksum_fixup(*ic, oip, *ip, 0);
if (pc != NULL)
*ic = pf_cksum_fixup(*ic, opc, *pc, 0);
}
/* Change inner ip address, fix inner ip and icmp checksums. */
PF_ACPY(ia, na, af);
switch (af) {
#ifdef INET
case AF_INET: {
u_int32_t oh2c = *h2c;
*h2c = pf_cksum_fixup(pf_cksum_fixup(*h2c,
oia.addr16[0], ia->addr16[0], 0),
oia.addr16[1], ia->addr16[1], 0);
*ic = pf_cksum_fixup(pf_cksum_fixup(*ic,
oia.addr16[0], ia->addr16[0], 0),
oia.addr16[1], ia->addr16[1], 0);
*ic = pf_cksum_fixup(*ic, oh2c, *h2c, 0);
break;
}
#endif /* INET */
#ifdef INET6
case AF_INET6:
*ic = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
pf_cksum_fixup(pf_cksum_fixup(*ic,
oia.addr16[0], ia->addr16[0], u),
oia.addr16[1], ia->addr16[1], u),
oia.addr16[2], ia->addr16[2], u),
oia.addr16[3], ia->addr16[3], u),
oia.addr16[4], ia->addr16[4], u),
oia.addr16[5], ia->addr16[5], u),
oia.addr16[6], ia->addr16[6], u),
oia.addr16[7], ia->addr16[7], u);
break;
#endif /* INET6 */
}
/* Outer ip address, fix outer ip or icmpv6 checksum, if necessary. */
if (oa) {
PF_ACPY(oa, na, af);
switch (af) {
#ifdef INET
case AF_INET:
*hc = pf_cksum_fixup(pf_cksum_fixup(*hc,
ooa.addr16[0], oa->addr16[0], 0),
ooa.addr16[1], oa->addr16[1], 0);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
*ic = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
pf_cksum_fixup(pf_cksum_fixup(*ic,
ooa.addr16[0], oa->addr16[0], u),
ooa.addr16[1], oa->addr16[1], u),
ooa.addr16[2], oa->addr16[2], u),
ooa.addr16[3], oa->addr16[3], u),
ooa.addr16[4], oa->addr16[4], u),
ooa.addr16[5], oa->addr16[5], u),
ooa.addr16[6], oa->addr16[6], u),
ooa.addr16[7], oa->addr16[7], u);
break;
#endif /* INET6 */
}
}
}
/*
* Need to modulate the sequence numbers in the TCP SACK option
* (credits to Krzysztof Pfaff for report and patch)
*/
int
pf_modulate_sack(struct mbuf *m, int off, struct pf_pdesc *pd,
struct tcphdr *th, struct pf_state_peer *dst)
{
int hlen = (th->th_off << 2) - sizeof(*th), thoptlen = hlen;
#ifdef __FreeBSD__
u_int8_t opts[TCP_MAXOLEN], *opt = opts;
#else
u_int8_t opts[MAX_TCPOPTLEN], *opt = opts;
#endif
int copyback = 0, i, olen;
struct sackblk sack;
#define TCPOLEN_SACKLEN (TCPOLEN_SACK + 2)
if (hlen < TCPOLEN_SACKLEN ||
!pf_pull_hdr(m, off + sizeof(*th), opts, hlen, NULL, NULL, pd->af))
return 0;
while (hlen >= TCPOLEN_SACKLEN) {
olen = opt[1];
switch (*opt) {
case TCPOPT_EOL: /* FALLTHROUGH */
case TCPOPT_NOP:
opt++;
hlen--;
break;
case TCPOPT_SACK:
if (olen > hlen)
olen = hlen;
if (olen >= TCPOLEN_SACKLEN) {
for (i = 2; i + TCPOLEN_SACK <= olen;
i += TCPOLEN_SACK) {
memcpy(&sack, &opt[i], sizeof(sack));
pf_change_a(&sack.start, &th->th_sum,
htonl(ntohl(sack.start) -
dst->seqdiff), 0);
pf_change_a(&sack.end, &th->th_sum,
htonl(ntohl(sack.end) -
dst->seqdiff), 0);
memcpy(&opt[i], &sack, sizeof(sack));
}
copyback = 1;
}
/* FALLTHROUGH */
default:
if (olen < 2)
olen = 2;
hlen -= olen;
opt += olen;
}
}
if (copyback)
#ifdef __FreeBSD__
m_copyback(m, off + sizeof(*th), thoptlen, (caddr_t)opts);
#else
m_copyback(m, off + sizeof(*th), thoptlen, opts);
#endif
return (copyback);
}
void
#ifdef __FreeBSD__
pf_send_tcp(struct mbuf *replyto, const struct pf_rule *r, sa_family_t af,
#else
pf_send_tcp(const struct pf_rule *r, sa_family_t af,
#endif
const struct pf_addr *saddr, const struct pf_addr *daddr,
u_int16_t sport, u_int16_t dport, u_int32_t seq, u_int32_t ack,
u_int8_t flags, u_int16_t win, u_int16_t mss, u_int8_t ttl, int tag,
u_int16_t rtag, struct ether_header *eh, struct ifnet *ifp)
{
struct mbuf *m;
int len, tlen;
#ifdef INET
struct ip *h;
#endif /* INET */
#ifdef INET6
struct ip6_hdr *h6;
#endif /* INET6 */
struct tcphdr *th;
char *opt;
#ifdef __FreeBSD__
struct pf_mtag *pf_mtag;
KASSERT(
#ifdef INET
af == AF_INET
#else
0
#endif
||
#ifdef INET6
af == AF_INET6
#else
0
#endif
, ("Unsupported AF %d", af));
len = 0;
th = NULL;
#ifdef INET
h = NULL;
#endif
#ifdef INET6
h6 = NULL;
#endif
#endif /* __FreeBSD__ */
/* maximum segment size tcp option */
tlen = sizeof(struct tcphdr);
if (mss)
tlen += 4;
switch (af) {
#ifdef INET
case AF_INET:
len = sizeof(struct ip) + tlen;
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
len = sizeof(struct ip6_hdr) + tlen;
break;
#endif /* INET6 */
}
/* create outgoing mbuf */
m = m_gethdr(M_DONTWAIT, MT_HEADER);
if (m == NULL)
return;
#ifdef __FreeBSD__
#ifdef MAC
mac_netinet_firewall_send(m);
#endif
if ((pf_mtag = pf_get_mtag(m)) == NULL) {
m_freem(m);
return;
}
#endif
if (tag)
#ifdef __FreeBSD__
m->m_flags |= M_SKIP_FIREWALL;
pf_mtag->tag = rtag;
#else
m->m_pkthdr.pf.flags |= PF_TAG_GENERATED;
m->m_pkthdr.pf.tag = rtag;
#endif
if (r != NULL && r->rtableid >= 0)
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
#ifdef __FreeBSD__
{
M_SETFIB(m, r->rtableid);
pf_mtag->rtableid = r->rtableid;
#else
m->m_pkthdr.pf.rtableid = r->rtableid;
#endif
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
#ifdef __FreeBSD__
}
#endif
#ifdef ALTQ
if (r != NULL && r->qid) {
#ifdef __FreeBSD__
pf_mtag->qid = r->qid;
/* add hints for ecn */
pf_mtag->hdr = mtod(m, struct ip *);
#else
m->m_pkthdr.pf.qid = r->qid;
/* add hints for ecn */
m->m_pkthdr.pf.hdr = mtod(m, struct ip *);
#endif
}
#endif /* ALTQ */
m->m_data += max_linkhdr;
m->m_pkthdr.len = m->m_len = len;
m->m_pkthdr.rcvif = NULL;
bzero(m->m_data, len);
switch (af) {
#ifdef INET
case AF_INET:
h = mtod(m, struct ip *);
/* IP header fields included in the TCP checksum */
h->ip_p = IPPROTO_TCP;
h->ip_len = htons(tlen);
h->ip_src.s_addr = saddr->v4.s_addr;
h->ip_dst.s_addr = daddr->v4.s_addr;
th = (struct tcphdr *)((caddr_t)h + sizeof(struct ip));
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
h6 = mtod(m, struct ip6_hdr *);
/* IP header fields included in the TCP checksum */
h6->ip6_nxt = IPPROTO_TCP;
h6->ip6_plen = htons(tlen);
memcpy(&h6->ip6_src, &saddr->v6, sizeof(struct in6_addr));
memcpy(&h6->ip6_dst, &daddr->v6, sizeof(struct in6_addr));
th = (struct tcphdr *)((caddr_t)h6 + sizeof(struct ip6_hdr));
break;
#endif /* INET6 */
}
/* TCP header */
th->th_sport = sport;
th->th_dport = dport;
th->th_seq = htonl(seq);
th->th_ack = htonl(ack);
th->th_off = tlen >> 2;
th->th_flags = flags;
th->th_win = htons(win);
if (mss) {
opt = (char *)(th + 1);
opt[0] = TCPOPT_MAXSEG;
opt[1] = 4;
HTONS(mss);
bcopy((caddr_t)&mss, (caddr_t)(opt + 2), 2);
}
switch (af) {
#ifdef INET
case AF_INET:
/* TCP checksum */
th->th_sum = in_cksum(m, len);
/* Finish the IP header */
h->ip_v = 4;
h->ip_hl = sizeof(*h) >> 2;
h->ip_tos = IPTOS_LOWDELAY;
#ifdef __FreeBSD__
h->ip_off = V_path_mtu_discovery ? IP_DF : 0;
h->ip_len = len;
h->ip_ttl = ttl ? ttl : V_ip_defttl;
#else
h->ip_len = htons(len);
h->ip_off = htons(ip_mtudisc ? IP_DF : 0);
h->ip_ttl = ttl ? ttl : ip_defttl;
#endif
h->ip_sum = 0;
if (eh == NULL) {
#ifdef __FreeBSD__
PF_UNLOCK();
ip_output(m, (void *)NULL, (void *)NULL, 0,
(void *)NULL, (void *)NULL);
PF_LOCK();
#else /* ! __FreeBSD__ */
ip_output(m, (void *)NULL, (void *)NULL, 0,
(void *)NULL, (void *)NULL);
#endif
} else {
struct route ro;
struct rtentry rt;
struct ether_header *e = (void *)ro.ro_dst.sa_data;
if (ifp == NULL) {
m_freem(m);
return;
}
rt.rt_ifp = ifp;
ro.ro_rt = &rt;
ro.ro_dst.sa_len = sizeof(ro.ro_dst);
ro.ro_dst.sa_family = pseudo_AF_HDRCMPLT;
bcopy(eh->ether_dhost, e->ether_shost, ETHER_ADDR_LEN);
bcopy(eh->ether_shost, e->ether_dhost, ETHER_ADDR_LEN);
e->ether_type = eh->ether_type;
#ifdef __FreeBSD__
PF_UNLOCK();
/* XXX_IMPORT: later */
ip_output(m, (void *)NULL, &ro, 0,
(void *)NULL, (void *)NULL);
PF_LOCK();
#else /* ! __FreeBSD__ */
ip_output(m, (void *)NULL, &ro, IP_ROUTETOETHER,
(void *)NULL, (void *)NULL);
#endif
}
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
/* TCP checksum */
th->th_sum = in6_cksum(m, IPPROTO_TCP,
sizeof(struct ip6_hdr), tlen);
h6->ip6_vfc |= IPV6_VERSION;
h6->ip6_hlim = IPV6_DEFHLIM;
#ifdef __FreeBSD__
PF_UNLOCK();
ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL);
PF_LOCK();
#else
ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL);
#endif
break;
#endif /* INET6 */
}
}
static void
pf_send_icmp(struct mbuf *m, u_int8_t type, u_int8_t code, sa_family_t af,
struct pf_rule *r)
{
struct mbuf *m0;
#ifdef __FreeBSD__
#ifdef INET
struct ip *ip;
#endif
struct pf_mtag *pf_mtag;
#endif
#ifdef __FreeBSD__
m0 = m_copypacket(m, M_DONTWAIT);
if (m0 == NULL)
return;
#else
if ((m0 = m_copy(m, 0, M_COPYALL)) == NULL)
return;
#endif
#ifdef __FreeBSD__
if ((pf_mtag = pf_get_mtag(m0)) == NULL)
return;
/* XXX: revisit */
m0->m_flags |= M_SKIP_FIREWALL;
#else
m0->m_pkthdr.pf.flags |= PF_TAG_GENERATED;
#endif
if (r->rtableid >= 0)
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
#ifdef __FreeBSD__
{
M_SETFIB(m0, r->rtableid);
pf_mtag->rtableid = r->rtableid;
#else
m0->m_pkthdr.pf.rtableid = r->rtableid;
#endif
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
#ifdef __FreeBSD__
}
#endif
#ifdef ALTQ
if (r->qid) {
#ifdef __FreeBSD__
pf_mtag->qid = r->qid;
/* add hints for ecn */
pf_mtag->hdr = mtod(m0, struct ip *);
#else
m0->m_pkthdr.pf.qid = r->qid;
/* add hints for ecn */
m0->m_pkthdr.pf.hdr = mtod(m0, struct ip *);
#endif
}
#endif /* ALTQ */
switch (af) {
#ifdef INET
case AF_INET:
#ifdef __FreeBSD__
/* icmp_error() expects host byte ordering */
ip = mtod(m0, struct ip *);
NTOHS(ip->ip_len);
NTOHS(ip->ip_off);
PF_UNLOCK();
icmp_error(m0, type, code, 0, 0);
PF_LOCK();
#else
icmp_error(m0, type, code, 0, 0);
#endif
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
#ifdef __FreeBSD__
PF_UNLOCK();
#endif
icmp6_error(m0, type, code, 0);
#ifdef __FreeBSD__
PF_LOCK();
#endif
break;
#endif /* INET6 */
}
}
/*
* Return 1 if the addresses a and b match (with mask m), otherwise return 0.
* If n is 0, they match if they are equal. If n is != 0, they match if they
* are different.
*/
int
pf_match_addr(u_int8_t n, struct pf_addr *a, struct pf_addr *m,
struct pf_addr *b, sa_family_t af)
{
int match = 0;
switch (af) {
#ifdef INET
case AF_INET:
if ((a->addr32[0] & m->addr32[0]) ==
(b->addr32[0] & m->addr32[0]))
match++;
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
if (((a->addr32[0] & m->addr32[0]) ==
(b->addr32[0] & m->addr32[0])) &&
((a->addr32[1] & m->addr32[1]) ==
(b->addr32[1] & m->addr32[1])) &&
((a->addr32[2] & m->addr32[2]) ==
(b->addr32[2] & m->addr32[2])) &&
((a->addr32[3] & m->addr32[3]) ==
(b->addr32[3] & m->addr32[3])))
match++;
break;
#endif /* INET6 */
}
if (match) {
if (n)
return (0);
else
return (1);
} else {
if (n)
return (1);
else
return (0);
}
}
/*
* Return 1 if b <= a <= e, otherwise return 0.
*/
int
pf_match_addr_range(struct pf_addr *b, struct pf_addr *e,
struct pf_addr *a, sa_family_t af)
{
switch (af) {
#ifdef INET
case AF_INET:
if ((a->addr32[0] < b->addr32[0]) ||
(a->addr32[0] > e->addr32[0]))
return (0);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6: {
int i;
/* check a >= b */
for (i = 0; i < 4; ++i)
if (a->addr32[i] > b->addr32[i])
break;
else if (a->addr32[i] < b->addr32[i])
return (0);
/* check a <= e */
for (i = 0; i < 4; ++i)
if (a->addr32[i] < e->addr32[i])
break;
else if (a->addr32[i] > e->addr32[i])
return (0);
break;
}
#endif /* INET6 */
}
return (1);
}
int
pf_match(u_int8_t op, u_int32_t a1, u_int32_t a2, u_int32_t p)
{
switch (op) {
case PF_OP_IRG:
return ((p > a1) && (p < a2));
case PF_OP_XRG:
return ((p < a1) || (p > a2));
case PF_OP_RRG:
return ((p >= a1) && (p <= a2));
case PF_OP_EQ:
return (p == a1);
case PF_OP_NE:
return (p != a1);
case PF_OP_LT:
return (p < a1);
case PF_OP_LE:
return (p <= a1);
case PF_OP_GT:
return (p > a1);
case PF_OP_GE:
return (p >= a1);
}
return (0); /* never reached */
}
int
pf_match_port(u_int8_t op, u_int16_t a1, u_int16_t a2, u_int16_t p)
{
NTOHS(a1);
NTOHS(a2);
NTOHS(p);
return (pf_match(op, a1, a2, p));
}
int
pf_match_uid(u_int8_t op, uid_t a1, uid_t a2, uid_t u)
{
if (u == UID_MAX && op != PF_OP_EQ && op != PF_OP_NE)
return (0);
return (pf_match(op, a1, a2, u));
}
int
pf_match_gid(u_int8_t op, gid_t a1, gid_t a2, gid_t g)
{
if (g == GID_MAX && op != PF_OP_EQ && op != PF_OP_NE)
return (0);
return (pf_match(op, a1, a2, g));
}
int
#ifdef __FreeBSD__
pf_match_tag(struct mbuf *m, struct pf_rule *r, int *tag,
struct pf_mtag *pf_mtag)
#else
pf_match_tag(struct mbuf *m, struct pf_rule *r, int *tag)
#endif
{
if (*tag == -1)
#ifdef __FreeBSD__
*tag = pf_mtag->tag;
#else
*tag = m->m_pkthdr.pf.tag;
#endif
return ((!r->match_tag_not && r->match_tag == *tag) ||
(r->match_tag_not && r->match_tag != *tag));
}
int
#ifdef __FreeBSD__
pf_tag_packet(struct mbuf *m, int tag, int rtableid,
struct pf_mtag *pf_mtag)
#else
pf_tag_packet(struct mbuf *m, int tag, int rtableid)
#endif
{
if (tag <= 0 && rtableid < 0)
return (0);
if (tag > 0)
#ifdef __FreeBSD__
pf_mtag->tag = tag;
#else
m->m_pkthdr.pf.tag = tag;
#endif
if (rtableid >= 0)
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
#ifdef __FreeBSD__
{
M_SETFIB(m, rtableid);
}
#else
m->m_pkthdr.pf.rtableid = rtableid;
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
#endif
return (0);
}
void
pf_step_into_anchor(int *depth, struct pf_ruleset **rs, int n,
struct pf_rule **r, struct pf_rule **a, int *match)
{
struct pf_anchor_stackframe *f;
(*r)->anchor->match = 0;
if (match)
*match = 0;
#ifdef __FreeBSD__
if (*depth >= sizeof(V_pf_anchor_stack) /
sizeof(V_pf_anchor_stack[0])) {
#else
if (*depth >= sizeof(pf_anchor_stack) /
sizeof(pf_anchor_stack[0])) {
#endif
printf("pf_step_into_anchor: stack overflow\n");
*r = TAILQ_NEXT(*r, entries);
return;
} else if (*depth == 0 && a != NULL)
*a = *r;
#ifdef __FreeBSD__
f = V_pf_anchor_stack + (*depth)++;
#else
f = pf_anchor_stack + (*depth)++;
#endif
f->rs = *rs;
f->r = *r;
if ((*r)->anchor_wildcard) {
f->parent = &(*r)->anchor->children;
if ((f->child = RB_MIN(pf_anchor_node, f->parent)) ==
NULL) {
*r = NULL;
return;
}
*rs = &f->child->ruleset;
} else {
f->parent = NULL;
f->child = NULL;
*rs = &(*r)->anchor->ruleset;
}
*r = TAILQ_FIRST((*rs)->rules[n].active.ptr);
}
int
pf_step_out_of_anchor(int *depth, struct pf_ruleset **rs, int n,
struct pf_rule **r, struct pf_rule **a, int *match)
{
struct pf_anchor_stackframe *f;
int quick = 0;
do {
if (*depth <= 0)
break;
#ifdef __FreeBSD__
f = V_pf_anchor_stack + *depth - 1;
#else
f = pf_anchor_stack + *depth - 1;
#endif
if (f->parent != NULL && f->child != NULL) {
if (f->child->match ||
(match != NULL && *match)) {
f->r->anchor->match = 1;
*match = 0;
}
f->child = RB_NEXT(pf_anchor_node, f->parent, f->child);
if (f->child != NULL) {
*rs = &f->child->ruleset;
*r = TAILQ_FIRST((*rs)->rules[n].active.ptr);
if (*r == NULL)
continue;
else
break;
}
}
(*depth)--;
if (*depth == 0 && a != NULL)
*a = NULL;
*rs = f->rs;
if (f->r->anchor->match || (match != NULL && *match))
quick = f->r->quick;
*r = TAILQ_NEXT(f->r, entries);
} while (*r == NULL);
return (quick);
}
#ifdef INET6
void
pf_poolmask(struct pf_addr *naddr, struct pf_addr *raddr,
struct pf_addr *rmask, struct pf_addr *saddr, sa_family_t af)
{
switch (af) {
#ifdef INET
case AF_INET:
naddr->addr32[0] = (raddr->addr32[0] & rmask->addr32[0]) |
((rmask->addr32[0] ^ 0xffffffff ) & saddr->addr32[0]);
break;
#endif /* INET */
case AF_INET6:
naddr->addr32[0] = (raddr->addr32[0] & rmask->addr32[0]) |
((rmask->addr32[0] ^ 0xffffffff ) & saddr->addr32[0]);
naddr->addr32[1] = (raddr->addr32[1] & rmask->addr32[1]) |
((rmask->addr32[1] ^ 0xffffffff ) & saddr->addr32[1]);
naddr->addr32[2] = (raddr->addr32[2] & rmask->addr32[2]) |
((rmask->addr32[2] ^ 0xffffffff ) & saddr->addr32[2]);
naddr->addr32[3] = (raddr->addr32[3] & rmask->addr32[3]) |
((rmask->addr32[3] ^ 0xffffffff ) & saddr->addr32[3]);
break;
}
}
void
pf_addr_inc(struct pf_addr *addr, sa_family_t af)
{
switch (af) {
#ifdef INET
case AF_INET:
addr->addr32[0] = htonl(ntohl(addr->addr32[0]) + 1);
break;
#endif /* INET */
case AF_INET6:
if (addr->addr32[3] == 0xffffffff) {
addr->addr32[3] = 0;
if (addr->addr32[2] == 0xffffffff) {
addr->addr32[2] = 0;
if (addr->addr32[1] == 0xffffffff) {
addr->addr32[1] = 0;
addr->addr32[0] =
htonl(ntohl(addr->addr32[0]) + 1);
} else
addr->addr32[1] =
htonl(ntohl(addr->addr32[1]) + 1);
} else
addr->addr32[2] =
htonl(ntohl(addr->addr32[2]) + 1);
} else
addr->addr32[3] =
htonl(ntohl(addr->addr32[3]) + 1);
break;
}
}
#endif /* INET6 */
int
#ifdef __FreeBSD__
pf_socket_lookup(int direction, struct pf_pdesc *pd, struct inpcb *inp_arg)
#else
pf_socket_lookup(int direction, struct pf_pdesc *pd)
#endif
{
struct pf_addr *saddr, *daddr;
u_int16_t sport, dport;
#ifdef __FreeBSD__
struct inpcbinfo *pi;
#else
struct inpcbtable *tb;
#endif
struct inpcb *inp;
if (pd == NULL)
return (-1);
pd->lookup.uid = UID_MAX;
pd->lookup.gid = GID_MAX;
pd->lookup.pid = NO_PID;
#ifdef __FreeBSD__
if (inp_arg != NULL) {
INP_LOCK_ASSERT(inp_arg);
pd->lookup.uid = inp_arg->inp_cred->cr_uid;
pd->lookup.gid = inp_arg->inp_cred->cr_groups[0];
return (1);
}
#endif
switch (pd->proto) {
case IPPROTO_TCP:
if (pd->hdr.tcp == NULL)
return (-1);
sport = pd->hdr.tcp->th_sport;
dport = pd->hdr.tcp->th_dport;
#ifdef __FreeBSD__
pi = &V_tcbinfo;
#else
tb = &tcbtable;
#endif
break;
case IPPROTO_UDP:
if (pd->hdr.udp == NULL)
return (-1);
sport = pd->hdr.udp->uh_sport;
dport = pd->hdr.udp->uh_dport;
#ifdef __FreeBSD__
pi = &V_udbinfo;
#else
tb = &udbtable;
#endif
break;
default:
return (-1);
}
if (direction == PF_IN) {
saddr = pd->src;
daddr = pd->dst;
} else {
u_int16_t p;
p = sport;
sport = dport;
dport = p;
saddr = pd->dst;
daddr = pd->src;
}
switch (pd->af) {
#ifdef INET
case AF_INET:
#ifdef __FreeBSD__
/*
* XXXRW: would be nice if we had an mbuf here so that we
* could use in_pcblookup_mbuf().
*/
Decompose the current single inpcbinfo lock into two locks: - The existing ipi_lock continues to protect the global inpcb list and inpcb counter. This lock is now relegated to a small number of allocation and free operations, and occasional operations that walk all connections (including, awkwardly, certain UDP multicast receive operations -- something to revisit). - A new ipi_hash_lock protects the two inpcbinfo hash tables for looking up connections and bound sockets, manipulated using new INP_HASH_*() macros. This lock, combined with inpcb locks, protects the 4-tuple address space. Unlike the current ipi_lock, ipi_hash_lock follows the individual inpcb connection locks, so may be acquired while manipulating a connection on which a lock is already held, avoiding the need to acquire the inpcbinfo lock preemptively when a binding change might later be required. As a result, however, lookup operations necessarily go through a reference acquire while holding the lookup lock, later acquiring an inpcb lock -- if required. A new function in_pcblookup() looks up connections, and accepts flags indicating how to return the inpcb. Due to lock order changes, callers no longer need acquire locks before performing a lookup: the lookup routine will acquire the ipi_hash_lock as needed. In the future, it will also be able to use alternative lookup and locking strategies transparently to callers, such as pcbgroup lookup. New lookup flags are, supplementing the existing INPLOOKUP_WILDCARD flag: INPLOOKUP_RLOCKPCB - Acquire a read lock on the returned inpcb INPLOOKUP_WLOCKPCB - Acquire a write lock on the returned inpcb Callers must pass exactly one of these flags (for the time being). Some notes: - All protocols are updated to work within the new regime; especially, TCP, UDPv4, and UDPv6. pcbinfo ipi_lock acquisitions are largely eliminated, and global hash lock hold times are dramatically reduced compared to previous locking. - The TCP syncache still relies on the pcbinfo lock, something that we may want to revisit. - Support for reverting to the FreeBSD 7.x locking strategy in TCP input is no longer available -- hash lookup locks are now held only very briefly during inpcb lookup, rather than for potentially extended periods. However, the pcbinfo ipi_lock will still be acquired if a connection state might change such that a connection is added or removed. - Raw IP sockets continue to use the pcbinfo ipi_lock for protection, due to maintaining their own hash tables. - The interface in6_pcblookup_hash_locked() is maintained, which allows callers to acquire hash locks and perform one or more lookups atomically with 4-tuple allocation: this is required only for TCPv6, as there is no in6_pcbconnect_setup(), which there should be. - UDPv6 locking remains significantly more conservative than UDPv4 locking, which relates to source address selection. This needs attention, as it likely significantly reduces parallelism in this code for multithreaded socket use (such as in BIND). - In the UDPv4 and UDPv6 multicast cases, we need to revisit locking somewhat, as they relied on ipi_lock to stablise 4-tuple matches, which is no longer sufficient. A second check once the inpcb lock is held should do the trick, keeping the general case from requiring the inpcb lock for every inpcb visited. - This work reminds us that we need to revisit locking of the v4/v6 flags, which may be accessed lock-free both before and after this change. - Right now, a single lock name is used for the pcbhash lock -- this is undesirable, and probably another argument is required to take care of this (or a char array name field in the pcbinfo?). This is not an MFC candidate for 8.x due to its impact on lookup and locking semantics. It's possible some of these issues could be worked around with compatibility wrappers, if necessary. Reviewed by: bz Sponsored by: Juniper Networks, Inc.
2011-05-30 09:43:55 +00:00
inp = in_pcblookup(pi, saddr->v4, sport, daddr->v4,
dport, INPLOOKUP_RLOCKPCB, NULL);
if (inp == NULL) {
Decompose the current single inpcbinfo lock into two locks: - The existing ipi_lock continues to protect the global inpcb list and inpcb counter. This lock is now relegated to a small number of allocation and free operations, and occasional operations that walk all connections (including, awkwardly, certain UDP multicast receive operations -- something to revisit). - A new ipi_hash_lock protects the two inpcbinfo hash tables for looking up connections and bound sockets, manipulated using new INP_HASH_*() macros. This lock, combined with inpcb locks, protects the 4-tuple address space. Unlike the current ipi_lock, ipi_hash_lock follows the individual inpcb connection locks, so may be acquired while manipulating a connection on which a lock is already held, avoiding the need to acquire the inpcbinfo lock preemptively when a binding change might later be required. As a result, however, lookup operations necessarily go through a reference acquire while holding the lookup lock, later acquiring an inpcb lock -- if required. A new function in_pcblookup() looks up connections, and accepts flags indicating how to return the inpcb. Due to lock order changes, callers no longer need acquire locks before performing a lookup: the lookup routine will acquire the ipi_hash_lock as needed. In the future, it will also be able to use alternative lookup and locking strategies transparently to callers, such as pcbgroup lookup. New lookup flags are, supplementing the existing INPLOOKUP_WILDCARD flag: INPLOOKUP_RLOCKPCB - Acquire a read lock on the returned inpcb INPLOOKUP_WLOCKPCB - Acquire a write lock on the returned inpcb Callers must pass exactly one of these flags (for the time being). Some notes: - All protocols are updated to work within the new regime; especially, TCP, UDPv4, and UDPv6. pcbinfo ipi_lock acquisitions are largely eliminated, and global hash lock hold times are dramatically reduced compared to previous locking. - The TCP syncache still relies on the pcbinfo lock, something that we may want to revisit. - Support for reverting to the FreeBSD 7.x locking strategy in TCP input is no longer available -- hash lookup locks are now held only very briefly during inpcb lookup, rather than for potentially extended periods. However, the pcbinfo ipi_lock will still be acquired if a connection state might change such that a connection is added or removed. - Raw IP sockets continue to use the pcbinfo ipi_lock for protection, due to maintaining their own hash tables. - The interface in6_pcblookup_hash_locked() is maintained, which allows callers to acquire hash locks and perform one or more lookups atomically with 4-tuple allocation: this is required only for TCPv6, as there is no in6_pcbconnect_setup(), which there should be. - UDPv6 locking remains significantly more conservative than UDPv4 locking, which relates to source address selection. This needs attention, as it likely significantly reduces parallelism in this code for multithreaded socket use (such as in BIND). - In the UDPv4 and UDPv6 multicast cases, we need to revisit locking somewhat, as they relied on ipi_lock to stablise 4-tuple matches, which is no longer sufficient. A second check once the inpcb lock is held should do the trick, keeping the general case from requiring the inpcb lock for every inpcb visited. - This work reminds us that we need to revisit locking of the v4/v6 flags, which may be accessed lock-free both before and after this change. - Right now, a single lock name is used for the pcbhash lock -- this is undesirable, and probably another argument is required to take care of this (or a char array name field in the pcbinfo?). This is not an MFC candidate for 8.x due to its impact on lookup and locking semantics. It's possible some of these issues could be worked around with compatibility wrappers, if necessary. Reviewed by: bz Sponsored by: Juniper Networks, Inc.
2011-05-30 09:43:55 +00:00
inp = in_pcblookup(pi, saddr->v4, sport,
daddr->v4, dport, INPLOOKUP_WILDCARD |
INPLOOKUP_RLOCKPCB, NULL);
if (inp == NULL)
return (-1);
}
#else
inp = in_pcbhashlookup(tb, saddr->v4, sport, daddr->v4, dport);
if (inp == NULL) {
inp = in_pcblookup_listen(tb, daddr->v4, dport, 0,
NULL);
if (inp == NULL)
return (-1);
}
#endif
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
#ifdef __FreeBSD__
/*
* XXXRW: would be nice if we had an mbuf here so that we
* could use in6_pcblookup_mbuf().
*/
Decompose the current single inpcbinfo lock into two locks: - The existing ipi_lock continues to protect the global inpcb list and inpcb counter. This lock is now relegated to a small number of allocation and free operations, and occasional operations that walk all connections (including, awkwardly, certain UDP multicast receive operations -- something to revisit). - A new ipi_hash_lock protects the two inpcbinfo hash tables for looking up connections and bound sockets, manipulated using new INP_HASH_*() macros. This lock, combined with inpcb locks, protects the 4-tuple address space. Unlike the current ipi_lock, ipi_hash_lock follows the individual inpcb connection locks, so may be acquired while manipulating a connection on which a lock is already held, avoiding the need to acquire the inpcbinfo lock preemptively when a binding change might later be required. As a result, however, lookup operations necessarily go through a reference acquire while holding the lookup lock, later acquiring an inpcb lock -- if required. A new function in_pcblookup() looks up connections, and accepts flags indicating how to return the inpcb. Due to lock order changes, callers no longer need acquire locks before performing a lookup: the lookup routine will acquire the ipi_hash_lock as needed. In the future, it will also be able to use alternative lookup and locking strategies transparently to callers, such as pcbgroup lookup. New lookup flags are, supplementing the existing INPLOOKUP_WILDCARD flag: INPLOOKUP_RLOCKPCB - Acquire a read lock on the returned inpcb INPLOOKUP_WLOCKPCB - Acquire a write lock on the returned inpcb Callers must pass exactly one of these flags (for the time being). Some notes: - All protocols are updated to work within the new regime; especially, TCP, UDPv4, and UDPv6. pcbinfo ipi_lock acquisitions are largely eliminated, and global hash lock hold times are dramatically reduced compared to previous locking. - The TCP syncache still relies on the pcbinfo lock, something that we may want to revisit. - Support for reverting to the FreeBSD 7.x locking strategy in TCP input is no longer available -- hash lookup locks are now held only very briefly during inpcb lookup, rather than for potentially extended periods. However, the pcbinfo ipi_lock will still be acquired if a connection state might change such that a connection is added or removed. - Raw IP sockets continue to use the pcbinfo ipi_lock for protection, due to maintaining their own hash tables. - The interface in6_pcblookup_hash_locked() is maintained, which allows callers to acquire hash locks and perform one or more lookups atomically with 4-tuple allocation: this is required only for TCPv6, as there is no in6_pcbconnect_setup(), which there should be. - UDPv6 locking remains significantly more conservative than UDPv4 locking, which relates to source address selection. This needs attention, as it likely significantly reduces parallelism in this code for multithreaded socket use (such as in BIND). - In the UDPv4 and UDPv6 multicast cases, we need to revisit locking somewhat, as they relied on ipi_lock to stablise 4-tuple matches, which is no longer sufficient. A second check once the inpcb lock is held should do the trick, keeping the general case from requiring the inpcb lock for every inpcb visited. - This work reminds us that we need to revisit locking of the v4/v6 flags, which may be accessed lock-free both before and after this change. - Right now, a single lock name is used for the pcbhash lock -- this is undesirable, and probably another argument is required to take care of this (or a char array name field in the pcbinfo?). This is not an MFC candidate for 8.x due to its impact on lookup and locking semantics. It's possible some of these issues could be worked around with compatibility wrappers, if necessary. Reviewed by: bz Sponsored by: Juniper Networks, Inc.
2011-05-30 09:43:55 +00:00
inp = in6_pcblookup(pi, &saddr->v6, sport,
&daddr->v6, dport, INPLOOKUP_RLOCKPCB, NULL);
if (inp == NULL) {
Decompose the current single inpcbinfo lock into two locks: - The existing ipi_lock continues to protect the global inpcb list and inpcb counter. This lock is now relegated to a small number of allocation and free operations, and occasional operations that walk all connections (including, awkwardly, certain UDP multicast receive operations -- something to revisit). - A new ipi_hash_lock protects the two inpcbinfo hash tables for looking up connections and bound sockets, manipulated using new INP_HASH_*() macros. This lock, combined with inpcb locks, protects the 4-tuple address space. Unlike the current ipi_lock, ipi_hash_lock follows the individual inpcb connection locks, so may be acquired while manipulating a connection on which a lock is already held, avoiding the need to acquire the inpcbinfo lock preemptively when a binding change might later be required. As a result, however, lookup operations necessarily go through a reference acquire while holding the lookup lock, later acquiring an inpcb lock -- if required. A new function in_pcblookup() looks up connections, and accepts flags indicating how to return the inpcb. Due to lock order changes, callers no longer need acquire locks before performing a lookup: the lookup routine will acquire the ipi_hash_lock as needed. In the future, it will also be able to use alternative lookup and locking strategies transparently to callers, such as pcbgroup lookup. New lookup flags are, supplementing the existing INPLOOKUP_WILDCARD flag: INPLOOKUP_RLOCKPCB - Acquire a read lock on the returned inpcb INPLOOKUP_WLOCKPCB - Acquire a write lock on the returned inpcb Callers must pass exactly one of these flags (for the time being). Some notes: - All protocols are updated to work within the new regime; especially, TCP, UDPv4, and UDPv6. pcbinfo ipi_lock acquisitions are largely eliminated, and global hash lock hold times are dramatically reduced compared to previous locking. - The TCP syncache still relies on the pcbinfo lock, something that we may want to revisit. - Support for reverting to the FreeBSD 7.x locking strategy in TCP input is no longer available -- hash lookup locks are now held only very briefly during inpcb lookup, rather than for potentially extended periods. However, the pcbinfo ipi_lock will still be acquired if a connection state might change such that a connection is added or removed. - Raw IP sockets continue to use the pcbinfo ipi_lock for protection, due to maintaining their own hash tables. - The interface in6_pcblookup_hash_locked() is maintained, which allows callers to acquire hash locks and perform one or more lookups atomically with 4-tuple allocation: this is required only for TCPv6, as there is no in6_pcbconnect_setup(), which there should be. - UDPv6 locking remains significantly more conservative than UDPv4 locking, which relates to source address selection. This needs attention, as it likely significantly reduces parallelism in this code for multithreaded socket use (such as in BIND). - In the UDPv4 and UDPv6 multicast cases, we need to revisit locking somewhat, as they relied on ipi_lock to stablise 4-tuple matches, which is no longer sufficient. A second check once the inpcb lock is held should do the trick, keeping the general case from requiring the inpcb lock for every inpcb visited. - This work reminds us that we need to revisit locking of the v4/v6 flags, which may be accessed lock-free both before and after this change. - Right now, a single lock name is used for the pcbhash lock -- this is undesirable, and probably another argument is required to take care of this (or a char array name field in the pcbinfo?). This is not an MFC candidate for 8.x due to its impact on lookup and locking semantics. It's possible some of these issues could be worked around with compatibility wrappers, if necessary. Reviewed by: bz Sponsored by: Juniper Networks, Inc.
2011-05-30 09:43:55 +00:00
inp = in6_pcblookup(pi, &saddr->v6, sport,
&daddr->v6, dport, INPLOOKUP_WILDCARD |
INPLOOKUP_RLOCKPCB, NULL);
if (inp == NULL)
return (-1);
}
#else
inp = in6_pcbhashlookup(tb, &saddr->v6, sport, &daddr->v6,
dport);
if (inp == NULL) {
inp = in6_pcblookup_listen(tb, &daddr->v6, dport, 0,
NULL);
if (inp == NULL)
return (-1);
}
#endif
break;
#endif /* INET6 */
default:
return (-1);
}
#ifdef __FreeBSD__
Decompose the current single inpcbinfo lock into two locks: - The existing ipi_lock continues to protect the global inpcb list and inpcb counter. This lock is now relegated to a small number of allocation and free operations, and occasional operations that walk all connections (including, awkwardly, certain UDP multicast receive operations -- something to revisit). - A new ipi_hash_lock protects the two inpcbinfo hash tables for looking up connections and bound sockets, manipulated using new INP_HASH_*() macros. This lock, combined with inpcb locks, protects the 4-tuple address space. Unlike the current ipi_lock, ipi_hash_lock follows the individual inpcb connection locks, so may be acquired while manipulating a connection on which a lock is already held, avoiding the need to acquire the inpcbinfo lock preemptively when a binding change might later be required. As a result, however, lookup operations necessarily go through a reference acquire while holding the lookup lock, later acquiring an inpcb lock -- if required. A new function in_pcblookup() looks up connections, and accepts flags indicating how to return the inpcb. Due to lock order changes, callers no longer need acquire locks before performing a lookup: the lookup routine will acquire the ipi_hash_lock as needed. In the future, it will also be able to use alternative lookup and locking strategies transparently to callers, such as pcbgroup lookup. New lookup flags are, supplementing the existing INPLOOKUP_WILDCARD flag: INPLOOKUP_RLOCKPCB - Acquire a read lock on the returned inpcb INPLOOKUP_WLOCKPCB - Acquire a write lock on the returned inpcb Callers must pass exactly one of these flags (for the time being). Some notes: - All protocols are updated to work within the new regime; especially, TCP, UDPv4, and UDPv6. pcbinfo ipi_lock acquisitions are largely eliminated, and global hash lock hold times are dramatically reduced compared to previous locking. - The TCP syncache still relies on the pcbinfo lock, something that we may want to revisit. - Support for reverting to the FreeBSD 7.x locking strategy in TCP input is no longer available -- hash lookup locks are now held only very briefly during inpcb lookup, rather than for potentially extended periods. However, the pcbinfo ipi_lock will still be acquired if a connection state might change such that a connection is added or removed. - Raw IP sockets continue to use the pcbinfo ipi_lock for protection, due to maintaining their own hash tables. - The interface in6_pcblookup_hash_locked() is maintained, which allows callers to acquire hash locks and perform one or more lookups atomically with 4-tuple allocation: this is required only for TCPv6, as there is no in6_pcbconnect_setup(), which there should be. - UDPv6 locking remains significantly more conservative than UDPv4 locking, which relates to source address selection. This needs attention, as it likely significantly reduces parallelism in this code for multithreaded socket use (such as in BIND). - In the UDPv4 and UDPv6 multicast cases, we need to revisit locking somewhat, as they relied on ipi_lock to stablise 4-tuple matches, which is no longer sufficient. A second check once the inpcb lock is held should do the trick, keeping the general case from requiring the inpcb lock for every inpcb visited. - This work reminds us that we need to revisit locking of the v4/v6 flags, which may be accessed lock-free both before and after this change. - Right now, a single lock name is used for the pcbhash lock -- this is undesirable, and probably another argument is required to take care of this (or a char array name field in the pcbinfo?). This is not an MFC candidate for 8.x due to its impact on lookup and locking semantics. It's possible some of these issues could be worked around with compatibility wrappers, if necessary. Reviewed by: bz Sponsored by: Juniper Networks, Inc.
2011-05-30 09:43:55 +00:00
INP_RLOCK_ASSERT(inp);
pd->lookup.uid = inp->inp_cred->cr_uid;
pd->lookup.gid = inp->inp_cred->cr_groups[0];
Decompose the current single inpcbinfo lock into two locks: - The existing ipi_lock continues to protect the global inpcb list and inpcb counter. This lock is now relegated to a small number of allocation and free operations, and occasional operations that walk all connections (including, awkwardly, certain UDP multicast receive operations -- something to revisit). - A new ipi_hash_lock protects the two inpcbinfo hash tables for looking up connections and bound sockets, manipulated using new INP_HASH_*() macros. This lock, combined with inpcb locks, protects the 4-tuple address space. Unlike the current ipi_lock, ipi_hash_lock follows the individual inpcb connection locks, so may be acquired while manipulating a connection on which a lock is already held, avoiding the need to acquire the inpcbinfo lock preemptively when a binding change might later be required. As a result, however, lookup operations necessarily go through a reference acquire while holding the lookup lock, later acquiring an inpcb lock -- if required. A new function in_pcblookup() looks up connections, and accepts flags indicating how to return the inpcb. Due to lock order changes, callers no longer need acquire locks before performing a lookup: the lookup routine will acquire the ipi_hash_lock as needed. In the future, it will also be able to use alternative lookup and locking strategies transparently to callers, such as pcbgroup lookup. New lookup flags are, supplementing the existing INPLOOKUP_WILDCARD flag: INPLOOKUP_RLOCKPCB - Acquire a read lock on the returned inpcb INPLOOKUP_WLOCKPCB - Acquire a write lock on the returned inpcb Callers must pass exactly one of these flags (for the time being). Some notes: - All protocols are updated to work within the new regime; especially, TCP, UDPv4, and UDPv6. pcbinfo ipi_lock acquisitions are largely eliminated, and global hash lock hold times are dramatically reduced compared to previous locking. - The TCP syncache still relies on the pcbinfo lock, something that we may want to revisit. - Support for reverting to the FreeBSD 7.x locking strategy in TCP input is no longer available -- hash lookup locks are now held only very briefly during inpcb lookup, rather than for potentially extended periods. However, the pcbinfo ipi_lock will still be acquired if a connection state might change such that a connection is added or removed. - Raw IP sockets continue to use the pcbinfo ipi_lock for protection, due to maintaining their own hash tables. - The interface in6_pcblookup_hash_locked() is maintained, which allows callers to acquire hash locks and perform one or more lookups atomically with 4-tuple allocation: this is required only for TCPv6, as there is no in6_pcbconnect_setup(), which there should be. - UDPv6 locking remains significantly more conservative than UDPv4 locking, which relates to source address selection. This needs attention, as it likely significantly reduces parallelism in this code for multithreaded socket use (such as in BIND). - In the UDPv4 and UDPv6 multicast cases, we need to revisit locking somewhat, as they relied on ipi_lock to stablise 4-tuple matches, which is no longer sufficient. A second check once the inpcb lock is held should do the trick, keeping the general case from requiring the inpcb lock for every inpcb visited. - This work reminds us that we need to revisit locking of the v4/v6 flags, which may be accessed lock-free both before and after this change. - Right now, a single lock name is used for the pcbhash lock -- this is undesirable, and probably another argument is required to take care of this (or a char array name field in the pcbinfo?). This is not an MFC candidate for 8.x due to its impact on lookup and locking semantics. It's possible some of these issues could be worked around with compatibility wrappers, if necessary. Reviewed by: bz Sponsored by: Juniper Networks, Inc.
2011-05-30 09:43:55 +00:00
INP_RUNLOCK(inp);
#else
pd->lookup.uid = inp->inp_socket->so_euid;
pd->lookup.gid = inp->inp_socket->so_egid;
pd->lookup.pid = inp->inp_socket->so_cpid;
#endif
return (1);
}
u_int8_t
pf_get_wscale(struct mbuf *m, int off, u_int16_t th_off, sa_family_t af)
{
int hlen;
u_int8_t hdr[60];
u_int8_t *opt, optlen;
u_int8_t wscale = 0;
hlen = th_off << 2; /* hlen <= sizeof(hdr) */
if (hlen <= sizeof(struct tcphdr))
return (0);
if (!pf_pull_hdr(m, off, hdr, hlen, NULL, NULL, af))
return (0);
opt = hdr + sizeof(struct tcphdr);
hlen -= sizeof(struct tcphdr);
while (hlen >= 3) {
switch (*opt) {
case TCPOPT_EOL:
case TCPOPT_NOP:
++opt;
--hlen;
break;
case TCPOPT_WINDOW:
wscale = opt[2];
if (wscale > TCP_MAX_WINSHIFT)
wscale = TCP_MAX_WINSHIFT;
wscale |= PF_WSCALE_FLAG;
/* FALLTHROUGH */
default:
optlen = opt[1];
if (optlen < 2)
optlen = 2;
hlen -= optlen;
opt += optlen;
break;
}
}
return (wscale);
}
u_int16_t
pf_get_mss(struct mbuf *m, int off, u_int16_t th_off, sa_family_t af)
{
int hlen;
u_int8_t hdr[60];
u_int8_t *opt, optlen;
#ifdef __FreeBSD__
u_int16_t mss = V_tcp_mssdflt;
#else
u_int16_t mss = tcp_mssdflt;
#endif
hlen = th_off << 2; /* hlen <= sizeof(hdr) */
if (hlen <= sizeof(struct tcphdr))
return (0);
if (!pf_pull_hdr(m, off, hdr, hlen, NULL, NULL, af))
return (0);
opt = hdr + sizeof(struct tcphdr);
hlen -= sizeof(struct tcphdr);
while (hlen >= TCPOLEN_MAXSEG) {
switch (*opt) {
case TCPOPT_EOL:
case TCPOPT_NOP:
++opt;
--hlen;
break;
case TCPOPT_MAXSEG:
bcopy((caddr_t)(opt + 2), (caddr_t)&mss, 2);
NTOHS(mss);
/* FALLTHROUGH */
default:
optlen = opt[1];
if (optlen < 2)
optlen = 2;
hlen -= optlen;
opt += optlen;
break;
}
}
return (mss);
}
u_int16_t
pf_calc_mss(struct pf_addr *addr, sa_family_t af, u_int16_t offer)
{
#ifdef INET
struct sockaddr_in *dst;
struct route ro;
#endif /* INET */
#ifdef INET6
struct sockaddr_in6 *dst6;
struct route_in6 ro6;
#endif /* INET6 */
struct rtentry *rt = NULL;
#ifdef __FreeBSD__
int hlen = 0;
u_int16_t mss = V_tcp_mssdflt;
#else
int hlen;
u_int16_t mss = tcp_mssdflt;
#endif
switch (af) {
#ifdef INET
case AF_INET:
hlen = sizeof(struct ip);
bzero(&ro, sizeof(ro));
dst = (struct sockaddr_in *)&ro.ro_dst;
dst->sin_family = AF_INET;
dst->sin_len = sizeof(*dst);
dst->sin_addr = addr->v4;
#ifdef __FreeBSD__
#ifdef RTF_PRCLONING
rtalloc_ign(&ro, (RTF_CLONING | RTF_PRCLONING));
#else /* !RTF_PRCLONING */
in_rtalloc_ign(&ro, 0, 0);
#endif
#else /* ! __FreeBSD__ */
rtalloc_noclone(&ro, NO_CLONING);
#endif
rt = ro.ro_rt;
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
hlen = sizeof(struct ip6_hdr);
bzero(&ro6, sizeof(ro6));
dst6 = (struct sockaddr_in6 *)&ro6.ro_dst;
dst6->sin6_family = AF_INET6;
dst6->sin6_len = sizeof(*dst6);
dst6->sin6_addr = addr->v6;
#ifdef __FreeBSD__
#ifdef RTF_PRCLONING
rtalloc_ign((struct route *)&ro6,
(RTF_CLONING | RTF_PRCLONING));
#else /* !RTF_PRCLONING */
rtalloc_ign((struct route *)&ro6, 0);
#endif
#else /* ! __FreeBSD__ */
rtalloc_noclone((struct route *)&ro6, NO_CLONING);
#endif
rt = ro6.ro_rt;
break;
#endif /* INET6 */
}
if (rt && rt->rt_ifp) {
mss = rt->rt_ifp->if_mtu - hlen - sizeof(struct tcphdr);
#ifdef __FreeBSD__
mss = max(V_tcp_mssdflt, mss);
#else
mss = max(tcp_mssdflt, mss);
#endif
RTFREE(rt);
}
mss = min(mss, offer);
mss = max(mss, 64); /* sanity - at least max opt space */
return (mss);
}
void
pf_set_rt_ifp(struct pf_state *s, struct pf_addr *saddr)
{
struct pf_rule *r = s->rule.ptr;
struct pf_src_node *sn = NULL;
s->rt_kif = NULL;
if (!r->rt || r->rt == PF_FASTROUTE)
return;
switch (s->key[PF_SK_WIRE]->af) {
#ifdef INET
case AF_INET:
pf_map_addr(AF_INET, r, saddr, &s->rt_addr, NULL, &sn);
s->rt_kif = r->rpool.cur->kif;
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
pf_map_addr(AF_INET6, r, saddr, &s->rt_addr, NULL, &sn);
s->rt_kif = r->rpool.cur->kif;
break;
#endif /* INET6 */
}
}
u_int32_t
pf_tcp_iss(struct pf_pdesc *pd)
{
MD5_CTX ctx;
u_int32_t digest[4];
#ifdef __FreeBSD__
if (V_pf_tcp_secret_init == 0) {
read_random(&V_pf_tcp_secret, sizeof(V_pf_tcp_secret));
MD5Init(&V_pf_tcp_secret_ctx);
MD5Update(&V_pf_tcp_secret_ctx, V_pf_tcp_secret,
sizeof(V_pf_tcp_secret));
V_pf_tcp_secret_init = 1;
}
ctx = V_pf_tcp_secret_ctx;
#else
if (pf_tcp_secret_init == 0) {
arc4random_buf(pf_tcp_secret, sizeof(pf_tcp_secret));
MD5Init(&pf_tcp_secret_ctx);
MD5Update(&pf_tcp_secret_ctx, pf_tcp_secret,
sizeof(pf_tcp_secret));
pf_tcp_secret_init = 1;
}
ctx = pf_tcp_secret_ctx;
#endif
MD5Update(&ctx, (char *)&pd->hdr.tcp->th_sport, sizeof(u_short));
MD5Update(&ctx, (char *)&pd->hdr.tcp->th_dport, sizeof(u_short));
if (pd->af == AF_INET6) {
MD5Update(&ctx, (char *)&pd->src->v6, sizeof(struct in6_addr));
MD5Update(&ctx, (char *)&pd->dst->v6, sizeof(struct in6_addr));
} else {
MD5Update(&ctx, (char *)&pd->src->v4, sizeof(struct in_addr));
MD5Update(&ctx, (char *)&pd->dst->v4, sizeof(struct in_addr));
}
MD5Final((u_char *)digest, &ctx);
#ifdef __FreeBSD__
V_pf_tcp_iss_off += 4096;
#define ISN_RANDOM_INCREMENT (4096 - 1)
return (digest[0] + (arc4random() & ISN_RANDOM_INCREMENT) +
V_pf_tcp_iss_off);
#undef ISN_RANDOM_INCREMENT
#else
pf_tcp_iss_off += 4096;
return (digest[0] + tcp_iss + pf_tcp_iss_off);
#endif
}
int
pf_test_rule(struct pf_rule **rm, struct pf_state **sm, int direction,
struct pfi_kif *kif, struct mbuf *m, int off, void *h,
struct pf_pdesc *pd, struct pf_rule **am, struct pf_ruleset **rsm,
#ifdef __FreeBSD__
struct ifqueue *ifq, struct inpcb *inp)
#else
struct ifqueue *ifq)
#endif
{
struct pf_rule *nr = NULL;
struct pf_addr *saddr = pd->src, *daddr = pd->dst;
sa_family_t af = pd->af;
struct pf_rule *r, *a = NULL;
struct pf_ruleset *ruleset = NULL;
struct pf_src_node *nsn = NULL;
struct tcphdr *th = pd->hdr.tcp;
struct pf_state_key *skw = NULL, *sks = NULL;
struct pf_state_key *sk = NULL, *nk = NULL;
u_short reason;
int rewrite = 0, hdrlen = 0;
int tag = -1, rtableid = -1;
int asd = 0;
int match = 0;
int state_icmp = 0;
#ifdef __FreeBSD__
u_int16_t sport = 0, dport = 0;
u_int16_t bproto_sum = 0, bip_sum = 0;
#else
u_int16_t sport, dport;
u_int16_t bproto_sum = 0, bip_sum;
#endif
u_int8_t icmptype = 0, icmpcode = 0;
if (direction == PF_IN && pf_check_congestion(ifq)) {
REASON_SET(&reason, PFRES_CONGEST);
return (PF_DROP);
}
#ifdef __FreeBSD__
if (inp != NULL)
pd->lookup.done = pf_socket_lookup(direction, pd, inp);
else if (V_debug_pfugidhack) {
PF_UNLOCK();
DPFPRINTF(PF_DEBUG_MISC, ("pf: unlocked lookup\n"));
pd->lookup.done = pf_socket_lookup(direction, pd, inp);
PF_LOCK();
}
#endif
switch (pd->proto) {
case IPPROTO_TCP:
sport = th->th_sport;
dport = th->th_dport;
hdrlen = sizeof(*th);
break;
case IPPROTO_UDP:
sport = pd->hdr.udp->uh_sport;
dport = pd->hdr.udp->uh_dport;
hdrlen = sizeof(*pd->hdr.udp);
break;
#ifdef INET
case IPPROTO_ICMP:
if (pd->af != AF_INET)
break;
sport = dport = pd->hdr.icmp->icmp_id;
hdrlen = sizeof(*pd->hdr.icmp);
icmptype = pd->hdr.icmp->icmp_type;
icmpcode = pd->hdr.icmp->icmp_code;
if (icmptype == ICMP_UNREACH ||
icmptype == ICMP_SOURCEQUENCH ||
icmptype == ICMP_REDIRECT ||
icmptype == ICMP_TIMXCEED ||
icmptype == ICMP_PARAMPROB)
state_icmp++;
break;
#endif /* INET */
#ifdef INET6
case IPPROTO_ICMPV6:
if (af != AF_INET6)
break;
sport = dport = pd->hdr.icmp6->icmp6_id;
hdrlen = sizeof(*pd->hdr.icmp6);
icmptype = pd->hdr.icmp6->icmp6_type;
icmpcode = pd->hdr.icmp6->icmp6_code;
if (icmptype == ICMP6_DST_UNREACH ||
icmptype == ICMP6_PACKET_TOO_BIG ||
icmptype == ICMP6_TIME_EXCEEDED ||
icmptype == ICMP6_PARAM_PROB)
state_icmp++;
break;
#endif /* INET6 */
default:
sport = dport = hdrlen = 0;
break;
}
r = TAILQ_FIRST(pf_main_ruleset.rules[PF_RULESET_FILTER].active.ptr);
/* check packet for BINAT/NAT/RDR */
if ((nr = pf_get_translation(pd, m, off, direction, kif, &nsn,
&skw, &sks, &sk, &nk, saddr, daddr, sport, dport)) != NULL) {
if (nk == NULL || sk == NULL) {
REASON_SET(&reason, PFRES_MEMORY);
goto cleanup;
}
if (pd->ip_sum)
bip_sum = *pd->ip_sum;
switch (pd->proto) {
case IPPROTO_TCP:
bproto_sum = th->th_sum;
pd->proto_sum = &th->th_sum;
if (PF_ANEQ(saddr, &nk->addr[pd->sidx], af) ||
nk->port[pd->sidx] != sport) {
pf_change_ap(saddr, &th->th_sport, pd->ip_sum,
&th->th_sum, &nk->addr[pd->sidx],
nk->port[pd->sidx], 0, af);
pd->sport = &th->th_sport;
sport = th->th_sport;
}
if (PF_ANEQ(daddr, &nk->addr[pd->didx], af) ||
nk->port[pd->didx] != dport) {
pf_change_ap(daddr, &th->th_dport, pd->ip_sum,
&th->th_sum, &nk->addr[pd->didx],
nk->port[pd->didx], 0, af);
dport = th->th_dport;
pd->dport = &th->th_dport;
}
rewrite++;
break;
case IPPROTO_UDP:
bproto_sum = pd->hdr.udp->uh_sum;
pd->proto_sum = &pd->hdr.udp->uh_sum;
if (PF_ANEQ(saddr, &nk->addr[pd->sidx], af) ||
nk->port[pd->sidx] != sport) {
pf_change_ap(saddr, &pd->hdr.udp->uh_sport,
pd->ip_sum, &pd->hdr.udp->uh_sum,
&nk->addr[pd->sidx],
nk->port[pd->sidx], 1, af);
sport = pd->hdr.udp->uh_sport;
pd->sport = &pd->hdr.udp->uh_sport;
}
if (PF_ANEQ(daddr, &nk->addr[pd->didx], af) ||
nk->port[pd->didx] != dport) {
pf_change_ap(daddr, &pd->hdr.udp->uh_dport,
pd->ip_sum, &pd->hdr.udp->uh_sum,
&nk->addr[pd->didx],
nk->port[pd->didx], 1, af);
dport = pd->hdr.udp->uh_dport;
pd->dport = &pd->hdr.udp->uh_dport;
}
rewrite++;
break;
#ifdef INET
case IPPROTO_ICMP:
nk->port[0] = nk->port[1];
if (PF_ANEQ(saddr, &nk->addr[pd->sidx], AF_INET))
pf_change_a(&saddr->v4.s_addr, pd->ip_sum,
nk->addr[pd->sidx].v4.s_addr, 0);
if (PF_ANEQ(daddr, &nk->addr[pd->didx], AF_INET))
pf_change_a(&daddr->v4.s_addr, pd->ip_sum,
nk->addr[pd->didx].v4.s_addr, 0);
if (nk->port[1] != pd->hdr.icmp->icmp_id) {
pd->hdr.icmp->icmp_cksum = pf_cksum_fixup(
pd->hdr.icmp->icmp_cksum, sport,
nk->port[1], 0);
pd->hdr.icmp->icmp_id = nk->port[1];
pd->sport = &pd->hdr.icmp->icmp_id;
}
m_copyback(m, off, ICMP_MINLEN, (caddr_t)pd->hdr.icmp);
break;
#endif /* INET */
#ifdef INET6
case IPPROTO_ICMPV6:
nk->port[0] = nk->port[1];
if (PF_ANEQ(saddr, &nk->addr[pd->sidx], AF_INET6))
pf_change_a6(saddr, &pd->hdr.icmp6->icmp6_cksum,
&nk->addr[pd->sidx], 0);
if (PF_ANEQ(daddr, &nk->addr[pd->didx], AF_INET6))
pf_change_a6(daddr, &pd->hdr.icmp6->icmp6_cksum,
&nk->addr[pd->didx], 0);
rewrite++;
break;
#endif /* INET */
default:
switch (af) {
#ifdef INET
case AF_INET:
if (PF_ANEQ(saddr,
&nk->addr[pd->sidx], AF_INET))
pf_change_a(&saddr->v4.s_addr,
pd->ip_sum,
nk->addr[pd->sidx].v4.s_addr, 0);
if (PF_ANEQ(daddr,
&nk->addr[pd->didx], AF_INET))
pf_change_a(&daddr->v4.s_addr,
pd->ip_sum,
nk->addr[pd->didx].v4.s_addr, 0);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
if (PF_ANEQ(saddr,
&nk->addr[pd->sidx], AF_INET6))
PF_ACPY(saddr, &nk->addr[pd->sidx], af);
if (PF_ANEQ(daddr,
&nk->addr[pd->didx], AF_INET6))
PF_ACPY(saddr, &nk->addr[pd->didx], af);
break;
#endif /* INET */
}
break;
}
if (nr->natpass)
r = NULL;
pd->nat_rule = nr;
}
while (r != NULL) {
r->evaluations++;
if (pfi_kif_match(r->kif, kif) == r->ifnot)
r = r->skip[PF_SKIP_IFP].ptr;
else if (r->direction && r->direction != direction)
r = r->skip[PF_SKIP_DIR].ptr;
else if (r->af && r->af != af)
r = r->skip[PF_SKIP_AF].ptr;
else if (r->proto && r->proto != pd->proto)
r = r->skip[PF_SKIP_PROTO].ptr;
else if (PF_MISMATCHAW(&r->src.addr, saddr, af,
r->src.neg, kif))
r = r->skip[PF_SKIP_SRC_ADDR].ptr;
/* tcp/udp only. port_op always 0 in other cases */
else if (r->src.port_op && !pf_match_port(r->src.port_op,
r->src.port[0], r->src.port[1], sport))
r = r->skip[PF_SKIP_SRC_PORT].ptr;
else if (PF_MISMATCHAW(&r->dst.addr, daddr, af,
r->dst.neg, NULL))
r = r->skip[PF_SKIP_DST_ADDR].ptr;
/* tcp/udp only. port_op always 0 in other cases */
else if (r->dst.port_op && !pf_match_port(r->dst.port_op,
r->dst.port[0], r->dst.port[1], dport))
r = r->skip[PF_SKIP_DST_PORT].ptr;
/* icmp only. type always 0 in other cases */
else if (r->type && r->type != icmptype + 1)
r = TAILQ_NEXT(r, entries);
/* icmp only. type always 0 in other cases */
else if (r->code && r->code != icmpcode + 1)
r = TAILQ_NEXT(r, entries);
else if (r->tos && !(r->tos == pd->tos))
r = TAILQ_NEXT(r, entries);
else if (r->rule_flag & PFRULE_FRAGMENT)
r = TAILQ_NEXT(r, entries);
else if (pd->proto == IPPROTO_TCP &&
(r->flagset & th->th_flags) != r->flags)
r = TAILQ_NEXT(r, entries);
/* tcp/udp only. uid.op always 0 in other cases */
else if (r->uid.op && (pd->lookup.done || (pd->lookup.done =
#ifdef __FreeBSD__
pf_socket_lookup(direction, pd, inp), 1)) &&
#else
pf_socket_lookup(direction, pd), 1)) &&
#endif
!pf_match_uid(r->uid.op, r->uid.uid[0], r->uid.uid[1],
pd->lookup.uid))
r = TAILQ_NEXT(r, entries);
/* tcp/udp only. gid.op always 0 in other cases */
else if (r->gid.op && (pd->lookup.done || (pd->lookup.done =
#ifdef __FreeBSD__
pf_socket_lookup(direction, pd, inp), 1)) &&
#else
pf_socket_lookup(direction, pd), 1)) &&
#endif
!pf_match_gid(r->gid.op, r->gid.gid[0], r->gid.gid[1],
pd->lookup.gid))
r = TAILQ_NEXT(r, entries);
else if (r->prob &&
#ifdef __FreeBSD__
r->prob <= arc4random())
#else
r->prob <= arc4random_uniform(UINT_MAX - 1) + 1)
#endif
r = TAILQ_NEXT(r, entries);
#ifdef __FreeBSD__
else if (r->match_tag && !pf_match_tag(m, r, &tag, pd->pf_mtag))
#else
else if (r->match_tag && !pf_match_tag(m, r, &tag))
#endif
r = TAILQ_NEXT(r, entries);
else if (r->os_fingerprint != PF_OSFP_ANY &&
(pd->proto != IPPROTO_TCP || !pf_osfp_match(
pf_osfp_fingerprint(pd, m, off, th),
r->os_fingerprint)))
r = TAILQ_NEXT(r, entries);
else {
if (r->tag)
tag = r->tag;
if (r->rtableid >= 0)
rtableid = r->rtableid;
if (r->anchor == NULL) {
match = 1;
*rm = r;
*am = a;
*rsm = ruleset;
if ((*rm)->quick)
break;
r = TAILQ_NEXT(r, entries);
} else
pf_step_into_anchor(&asd, &ruleset,
PF_RULESET_FILTER, &r, &a, &match);
}
if (r == NULL && pf_step_out_of_anchor(&asd, &ruleset,
PF_RULESET_FILTER, &r, &a, &match))
break;
}
r = *rm;
a = *am;
ruleset = *rsm;
REASON_SET(&reason, PFRES_MATCH);
if (r->log || (nr != NULL && nr->log)) {
if (rewrite)
m_copyback(m, off, hdrlen, pd->hdr.any);
PFLOG_PACKET(kif, h, m, af, direction, reason, r->log ? r : nr,
a, ruleset, pd);
}
if ((r->action == PF_DROP) &&
((r->rule_flag & PFRULE_RETURNRST) ||
(r->rule_flag & PFRULE_RETURNICMP) ||
(r->rule_flag & PFRULE_RETURN))) {
/* undo NAT changes, if they have taken place */
if (nr != NULL) {
PF_ACPY(saddr, &sk->addr[pd->sidx], af);
PF_ACPY(daddr, &sk->addr[pd->didx], af);
if (pd->sport)
*pd->sport = sk->port[pd->sidx];
if (pd->dport)
*pd->dport = sk->port[pd->didx];
if (pd->proto_sum)
*pd->proto_sum = bproto_sum;
if (pd->ip_sum)
*pd->ip_sum = bip_sum;
m_copyback(m, off, hdrlen, pd->hdr.any);
}
if (pd->proto == IPPROTO_TCP &&
((r->rule_flag & PFRULE_RETURNRST) ||
(r->rule_flag & PFRULE_RETURN)) &&
!(th->th_flags & TH_RST)) {
u_int32_t ack = ntohl(th->th_seq) + pd->p_len;
int len = 0;
#ifdef INET
struct ip *h4;
#endif
#ifdef INET6
struct ip6_hdr *h6;
#endif
switch (af) {
#ifdef INET
case AF_INET:
h4 = mtod(m, struct ip *);
len = ntohs(h4->ip_len) - off;
break;
#endif
#ifdef INET6
case AF_INET6:
h6 = mtod(m, struct ip6_hdr *);
len = ntohs(h6->ip6_plen) - (off - sizeof(*h6));
break;
#endif
}
if (pf_check_proto_cksum(m, off, len, IPPROTO_TCP, af))
REASON_SET(&reason, PFRES_PROTCKSUM);
else {
if (th->th_flags & TH_SYN)
ack++;
if (th->th_flags & TH_FIN)
ack++;
#ifdef __FreeBSD__
pf_send_tcp(m, r, af, pd->dst,
#else
pf_send_tcp(r, af, pd->dst,
#endif
pd->src, th->th_dport, th->th_sport,
ntohl(th->th_ack), ack, TH_RST|TH_ACK, 0, 0,
r->return_ttl, 1, 0, pd->eh, kif->pfik_ifp);
}
} else if (pd->proto != IPPROTO_ICMP && af == AF_INET &&
r->return_icmp)
pf_send_icmp(m, r->return_icmp >> 8,
r->return_icmp & 255, af, r);
else if (pd->proto != IPPROTO_ICMPV6 && af == AF_INET6 &&
r->return_icmp6)
pf_send_icmp(m, r->return_icmp6 >> 8,
r->return_icmp6 & 255, af, r);
}
if (r->action == PF_DROP)
goto cleanup;
#ifdef __FreeBSD__
if (pf_tag_packet(m, tag, rtableid, pd->pf_mtag)) {
#else
if (pf_tag_packet(m, tag, rtableid)) {
#endif
REASON_SET(&reason, PFRES_MEMORY);
goto cleanup;
}
if (!state_icmp && (r->keep_state || nr != NULL ||
(pd->flags & PFDESC_TCP_NORM))) {
int action;
action = pf_create_state(r, nr, a, pd, nsn, skw, sks, nk, sk, m,
off, sport, dport, &rewrite, kif, sm, tag, bproto_sum,
bip_sum, hdrlen);
if (action != PF_PASS)
return (action);
} else {
#ifdef __FreeBSD__
if (sk != NULL)
pool_put(&V_pf_state_key_pl, sk);
if (nk != NULL)
pool_put(&V_pf_state_key_pl, nk);
#else
if (sk != NULL)
pool_put(&pf_state_key_pl, sk);
if (nk != NULL)
pool_put(&pf_state_key_pl, nk);
#endif
}
/* copy back packet headers if we performed NAT operations */
if (rewrite)
m_copyback(m, off, hdrlen, pd->hdr.any);
#if NPFSYNC > 0
if (*sm != NULL && !ISSET((*sm)->state_flags, PFSTATE_NOSYNC) &&
#ifdef __FreeBSD__
direction == PF_OUT && pfsync_up_ptr != NULL && pfsync_up_ptr()) {
#else
direction == PF_OUT && pfsync_up()) {
#endif
/*
* We want the state created, but we dont
* want to send this in case a partner
* firewall has to know about it to allow
* replies through it.
*/
#ifdef __FreeBSD__
if (pfsync_defer_ptr != NULL)
pfsync_defer_ptr(*sm, m);
#else
if (pfsync_defer(*sm, m))
#endif
return (PF_DEFER);
}
#endif
return (PF_PASS);
cleanup:
#ifdef __FreeBSD__
if (sk != NULL)
pool_put(&V_pf_state_key_pl, sk);
if (nk != NULL)
pool_put(&V_pf_state_key_pl, nk);
#else
if (sk != NULL)
pool_put(&pf_state_key_pl, sk);
if (nk != NULL)
pool_put(&pf_state_key_pl, nk);
#endif
return (PF_DROP);
}
static __inline int
pf_create_state(struct pf_rule *r, struct pf_rule *nr, struct pf_rule *a,
struct pf_pdesc *pd, struct pf_src_node *nsn, struct pf_state_key *skw,
struct pf_state_key *sks, struct pf_state_key *nk, struct pf_state_key *sk,
struct mbuf *m, int off, u_int16_t sport, u_int16_t dport, int *rewrite,
struct pfi_kif *kif, struct pf_state **sm, int tag, u_int16_t bproto_sum,
u_int16_t bip_sum, int hdrlen)
{
struct pf_state *s = NULL;
struct pf_src_node *sn = NULL;
struct tcphdr *th = pd->hdr.tcp;
#ifdef __FreeBSD__
u_int16_t mss = V_tcp_mssdflt;
#else
u_int16_t mss = tcp_mssdflt;
#endif
u_short reason;
/* check maximums */
if (r->max_states && (r->states_cur >= r->max_states)) {
#ifdef __FreeBSD__
V_pf_status.lcounters[LCNT_STATES]++;
#else
pf_status.lcounters[LCNT_STATES]++;
#endif
REASON_SET(&reason, PFRES_MAXSTATES);
return (PF_DROP);
}
/* src node for filter rule */
if ((r->rule_flag & PFRULE_SRCTRACK ||
r->rpool.opts & PF_POOL_STICKYADDR) &&
pf_insert_src_node(&sn, r, pd->src, pd->af) != 0) {
REASON_SET(&reason, PFRES_SRCLIMIT);
goto csfailed;
}
/* src node for translation rule */
if (nr != NULL && (nr->rpool.opts & PF_POOL_STICKYADDR) &&
pf_insert_src_node(&nsn, nr, &sk->addr[pd->sidx], pd->af)) {
REASON_SET(&reason, PFRES_SRCLIMIT);
goto csfailed;
}
#ifdef __FreeBSD__
s = pool_get(&V_pf_state_pl, PR_NOWAIT | PR_ZERO);
#else
s = pool_get(&pf_state_pl, PR_NOWAIT | PR_ZERO);
#endif
if (s == NULL) {
REASON_SET(&reason, PFRES_MEMORY);
goto csfailed;
}
s->rule.ptr = r;
s->nat_rule.ptr = nr;
s->anchor.ptr = a;
STATE_INC_COUNTERS(s);
if (r->allow_opts)
s->state_flags |= PFSTATE_ALLOWOPTS;
if (r->rule_flag & PFRULE_STATESLOPPY)
s->state_flags |= PFSTATE_SLOPPY;
if (r->rule_flag & PFRULE_PFLOW)
s->state_flags |= PFSTATE_PFLOW;
s->log = r->log & PF_LOG_ALL;
s->sync_state = PFSYNC_S_NONE;
if (nr != NULL)
s->log |= nr->log & PF_LOG_ALL;
switch (pd->proto) {
case IPPROTO_TCP:
s->src.seqlo = ntohl(th->th_seq);
s->src.seqhi = s->src.seqlo + pd->p_len + 1;
if ((th->th_flags & (TH_SYN|TH_ACK)) == TH_SYN &&
r->keep_state == PF_STATE_MODULATE) {
/* Generate sequence number modulator */
if ((s->src.seqdiff = pf_tcp_iss(pd) - s->src.seqlo) ==
0)
s->src.seqdiff = 1;
pf_change_a(&th->th_seq, &th->th_sum,
htonl(s->src.seqlo + s->src.seqdiff), 0);
*rewrite = 1;
} else
s->src.seqdiff = 0;
if (th->th_flags & TH_SYN) {
s->src.seqhi++;
s->src.wscale = pf_get_wscale(m, off,
th->th_off, pd->af);
}
s->src.max_win = MAX(ntohs(th->th_win), 1);
if (s->src.wscale & PF_WSCALE_MASK) {
/* Remove scale factor from initial window */
int win = s->src.max_win;
win += 1 << (s->src.wscale & PF_WSCALE_MASK);
s->src.max_win = (win - 1) >>
(s->src.wscale & PF_WSCALE_MASK);
}
if (th->th_flags & TH_FIN)
s->src.seqhi++;
s->dst.seqhi = 1;
s->dst.max_win = 1;
s->src.state = TCPS_SYN_SENT;
s->dst.state = TCPS_CLOSED;
s->timeout = PFTM_TCP_FIRST_PACKET;
break;
case IPPROTO_UDP:
s->src.state = PFUDPS_SINGLE;
s->dst.state = PFUDPS_NO_TRAFFIC;
s->timeout = PFTM_UDP_FIRST_PACKET;
break;
case IPPROTO_ICMP:
#ifdef INET6
case IPPROTO_ICMPV6:
#endif
s->timeout = PFTM_ICMP_FIRST_PACKET;
break;
default:
s->src.state = PFOTHERS_SINGLE;
s->dst.state = PFOTHERS_NO_TRAFFIC;
s->timeout = PFTM_OTHER_FIRST_PACKET;
}
s->creation = time_second;
s->expire = time_second;
if (sn != NULL) {
s->src_node = sn;
s->src_node->states++;
}
if (nsn != NULL) {
/* XXX We only modify one side for now. */
PF_ACPY(&nsn->raddr, &nk->addr[1], pd->af);
s->nat_src_node = nsn;
s->nat_src_node->states++;
}
if (pd->proto == IPPROTO_TCP) {
if ((pd->flags & PFDESC_TCP_NORM) && pf_normalize_tcp_init(m,
off, pd, th, &s->src, &s->dst)) {
REASON_SET(&reason, PFRES_MEMORY);
pf_src_tree_remove_state(s);
STATE_DEC_COUNTERS(s);
#ifdef __FreeBSD__
pool_put(&V_pf_state_pl, s);
#else
pool_put(&pf_state_pl, s);
#endif
return (PF_DROP);
}
if ((pd->flags & PFDESC_TCP_NORM) && s->src.scrub &&
pf_normalize_tcp_stateful(m, off, pd, &reason, th, s,
&s->src, &s->dst, rewrite)) {
/* This really shouldn't happen!!! */
DPFPRINTF(PF_DEBUG_URGENT,
("pf_normalize_tcp_stateful failed on first pkt"));
pf_normalize_tcp_cleanup(s);
pf_src_tree_remove_state(s);
STATE_DEC_COUNTERS(s);
#ifdef __FreeBSD__
pool_put(&V_pf_state_pl, s);
#else
pool_put(&pf_state_pl, s);
#endif
return (PF_DROP);
}
}
s->direction = pd->dir;
if (sk == NULL && pf_state_key_setup(pd, nr, &skw, &sks, &sk, &nk,
pd->src, pd->dst, sport, dport))
goto csfailed;
if (pf_state_insert(BOUND_IFACE(r, kif), skw, sks, s)) {
if (pd->proto == IPPROTO_TCP)
pf_normalize_tcp_cleanup(s);
REASON_SET(&reason, PFRES_STATEINS);
pf_src_tree_remove_state(s);
STATE_DEC_COUNTERS(s);
#ifdef __FreeBSD__
pool_put(&V_pf_state_pl, s);
#else
pool_put(&pf_state_pl, s);
#endif
return (PF_DROP);
} else
*sm = s;
pf_set_rt_ifp(s, pd->src); /* needs s->state_key set */
if (tag > 0) {
pf_tag_ref(tag);
s->tag = tag;
}
if (pd->proto == IPPROTO_TCP && (th->th_flags & (TH_SYN|TH_ACK)) ==
TH_SYN && r->keep_state == PF_STATE_SYNPROXY) {
s->src.state = PF_TCPS_PROXY_SRC;
/* undo NAT changes, if they have taken place */
if (nr != NULL) {
struct pf_state_key *skt = s->key[PF_SK_WIRE];
if (pd->dir == PF_OUT)
skt = s->key[PF_SK_STACK];
PF_ACPY(pd->src, &skt->addr[pd->sidx], pd->af);
PF_ACPY(pd->dst, &skt->addr[pd->didx], pd->af);
if (pd->sport)
*pd->sport = skt->port[pd->sidx];
if (pd->dport)
*pd->dport = skt->port[pd->didx];
if (pd->proto_sum)
*pd->proto_sum = bproto_sum;
if (pd->ip_sum)
*pd->ip_sum = bip_sum;
m_copyback(m, off, hdrlen, pd->hdr.any);
}
s->src.seqhi = htonl(arc4random());
/* Find mss option */
mss = pf_get_mss(m, off, th->th_off, pd->af);
mss = pf_calc_mss(pd->src, pd->af, mss);
mss = pf_calc_mss(pd->dst, pd->af, mss);
s->src.mss = mss;
#ifdef __FreeBSD__
pf_send_tcp(NULL, r, pd->af, pd->dst, pd->src, th->th_dport,
#else
pf_send_tcp(r, pd->af, pd->dst, pd->src, th->th_dport,
#endif
th->th_sport, s->src.seqhi, ntohl(th->th_seq) + 1,
TH_SYN|TH_ACK, 0, s->src.mss, 0, 1, 0, NULL, NULL);
REASON_SET(&reason, PFRES_SYNPROXY);
return (PF_SYNPROXY_DROP);
}
return (PF_PASS);
csfailed:
#ifdef __FreeBSD__
if (sk != NULL)
pool_put(&V_pf_state_key_pl, sk);
if (nk != NULL)
pool_put(&V_pf_state_key_pl, nk);
#else
if (sk != NULL)
pool_put(&pf_state_key_pl, sk);
if (nk != NULL)
pool_put(&pf_state_key_pl, nk);
#endif
if (sn != NULL && sn->states == 0 && sn->expire == 0) {
#ifdef __FreeBSD__
RB_REMOVE(pf_src_tree, &V_tree_src_tracking, sn);
V_pf_status.scounters[SCNT_SRC_NODE_REMOVALS]++;
V_pf_status.src_nodes--;
pool_put(&V_pf_src_tree_pl, sn);
#else
RB_REMOVE(pf_src_tree, &tree_src_tracking, sn);
pf_status.scounters[SCNT_SRC_NODE_REMOVALS]++;
pf_status.src_nodes--;
pool_put(&pf_src_tree_pl, sn);
#endif
}
if (nsn != sn && nsn != NULL && nsn->states == 0 && nsn->expire == 0) {
#ifdef __FreeBSD__
RB_REMOVE(pf_src_tree, &V_tree_src_tracking, nsn);
V_pf_status.scounters[SCNT_SRC_NODE_REMOVALS]++;
V_pf_status.src_nodes--;
pool_put(&V_pf_src_tree_pl, nsn);
#else
RB_REMOVE(pf_src_tree, &tree_src_tracking, nsn);
pf_status.scounters[SCNT_SRC_NODE_REMOVALS]++;
pf_status.src_nodes--;
pool_put(&pf_src_tree_pl, nsn);
#endif
}
return (PF_DROP);
}
int
pf_test_fragment(struct pf_rule **rm, int direction, struct pfi_kif *kif,
struct mbuf *m, void *h, struct pf_pdesc *pd, struct pf_rule **am,
struct pf_ruleset **rsm)
{
struct pf_rule *r, *a = NULL;
struct pf_ruleset *ruleset = NULL;
sa_family_t af = pd->af;
u_short reason;
int tag = -1;
int asd = 0;
int match = 0;
r = TAILQ_FIRST(pf_main_ruleset.rules[PF_RULESET_FILTER].active.ptr);
while (r != NULL) {
r->evaluations++;
if (pfi_kif_match(r->kif, kif) == r->ifnot)
r = r->skip[PF_SKIP_IFP].ptr;
else if (r->direction && r->direction != direction)
r = r->skip[PF_SKIP_DIR].ptr;
else if (r->af && r->af != af)
r = r->skip[PF_SKIP_AF].ptr;
else if (r->proto && r->proto != pd->proto)
r = r->skip[PF_SKIP_PROTO].ptr;
else if (PF_MISMATCHAW(&r->src.addr, pd->src, af,
r->src.neg, kif))
r = r->skip[PF_SKIP_SRC_ADDR].ptr;
else if (PF_MISMATCHAW(&r->dst.addr, pd->dst, af,
r->dst.neg, NULL))
r = r->skip[PF_SKIP_DST_ADDR].ptr;
else if (r->tos && !(r->tos == pd->tos))
r = TAILQ_NEXT(r, entries);
else if (r->os_fingerprint != PF_OSFP_ANY)
r = TAILQ_NEXT(r, entries);
else if (pd->proto == IPPROTO_UDP &&
(r->src.port_op || r->dst.port_op))
r = TAILQ_NEXT(r, entries);
else if (pd->proto == IPPROTO_TCP &&
(r->src.port_op || r->dst.port_op || r->flagset))
r = TAILQ_NEXT(r, entries);
else if ((pd->proto == IPPROTO_ICMP ||
pd->proto == IPPROTO_ICMPV6) &&
(r->type || r->code))
r = TAILQ_NEXT(r, entries);
else if (r->prob && r->prob <=
(arc4random() % (UINT_MAX - 1) + 1))
r = TAILQ_NEXT(r, entries);
#ifdef __FreeBSD__
else if (r->match_tag && !pf_match_tag(m, r, &tag, pd->pf_mtag))
#else
else if (r->match_tag && !pf_match_tag(m, r, &tag))
#endif
r = TAILQ_NEXT(r, entries);
else {
if (r->anchor == NULL) {
match = 1;
*rm = r;
*am = a;
*rsm = ruleset;
if ((*rm)->quick)
break;
r = TAILQ_NEXT(r, entries);
} else
pf_step_into_anchor(&asd, &ruleset,
PF_RULESET_FILTER, &r, &a, &match);
}
if (r == NULL && pf_step_out_of_anchor(&asd, &ruleset,
PF_RULESET_FILTER, &r, &a, &match))
break;
}
r = *rm;
a = *am;
ruleset = *rsm;
REASON_SET(&reason, PFRES_MATCH);
if (r->log)
PFLOG_PACKET(kif, h, m, af, direction, reason, r, a, ruleset,
pd);
if (r->action != PF_PASS)
return (PF_DROP);
#ifdef __FreeBSD__
if (pf_tag_packet(m, tag, -1, pd->pf_mtag)) {
#else
if (pf_tag_packet(m, tag, -1)) {
#endif
REASON_SET(&reason, PFRES_MEMORY);
return (PF_DROP);
}
return (PF_PASS);
}
int
pf_tcp_track_full(struct pf_state_peer *src, struct pf_state_peer *dst,
struct pf_state **state, struct pfi_kif *kif, struct mbuf *m, int off,
struct pf_pdesc *pd, u_short *reason, int *copyback)
{
struct tcphdr *th = pd->hdr.tcp;
u_int16_t win = ntohs(th->th_win);
u_int32_t ack, end, seq, orig_seq;
u_int8_t sws, dws;
int ackskew;
if (src->wscale && dst->wscale && !(th->th_flags & TH_SYN)) {
sws = src->wscale & PF_WSCALE_MASK;
dws = dst->wscale & PF_WSCALE_MASK;
} else
sws = dws = 0;
/*
* Sequence tracking algorithm from Guido van Rooij's paper:
* http://www.madison-gurkha.com/publications/tcp_filtering/
* tcp_filtering.ps
*/
orig_seq = seq = ntohl(th->th_seq);
if (src->seqlo == 0) {
/* First packet from this end. Set its state */
if ((pd->flags & PFDESC_TCP_NORM || dst->scrub) &&
src->scrub == NULL) {
if (pf_normalize_tcp_init(m, off, pd, th, src, dst)) {
REASON_SET(reason, PFRES_MEMORY);
return (PF_DROP);
}
}
/* Deferred generation of sequence number modulator */
if (dst->seqdiff && !src->seqdiff) {
/* use random iss for the TCP server */
while ((src->seqdiff = arc4random() - seq) == 0)
;
ack = ntohl(th->th_ack) - dst->seqdiff;
pf_change_a(&th->th_seq, &th->th_sum, htonl(seq +
src->seqdiff), 0);
pf_change_a(&th->th_ack, &th->th_sum, htonl(ack), 0);
*copyback = 1;
} else {
ack = ntohl(th->th_ack);
}
end = seq + pd->p_len;
if (th->th_flags & TH_SYN) {
end++;
if (dst->wscale & PF_WSCALE_FLAG) {
src->wscale = pf_get_wscale(m, off, th->th_off,
pd->af);
if (src->wscale & PF_WSCALE_FLAG) {
/* Remove scale factor from initial
* window */
sws = src->wscale & PF_WSCALE_MASK;
win = ((u_int32_t)win + (1 << sws) - 1)
>> sws;
dws = dst->wscale & PF_WSCALE_MASK;
} else {
/* fixup other window */
dst->max_win <<= dst->wscale &
PF_WSCALE_MASK;
/* in case of a retrans SYN|ACK */
dst->wscale = 0;
}
}
}
if (th->th_flags & TH_FIN)
end++;
src->seqlo = seq;
if (src->state < TCPS_SYN_SENT)
src->state = TCPS_SYN_SENT;
/*
* May need to slide the window (seqhi may have been set by
* the crappy stack check or if we picked up the connection
* after establishment)
*/
if (src->seqhi == 1 ||
SEQ_GEQ(end + MAX(1, dst->max_win << dws), src->seqhi))
src->seqhi = end + MAX(1, dst->max_win << dws);
if (win > src->max_win)
src->max_win = win;
} else {
ack = ntohl(th->th_ack) - dst->seqdiff;
if (src->seqdiff) {
/* Modulate sequence numbers */
pf_change_a(&th->th_seq, &th->th_sum, htonl(seq +
src->seqdiff), 0);
pf_change_a(&th->th_ack, &th->th_sum, htonl(ack), 0);
*copyback = 1;
}
end = seq + pd->p_len;
if (th->th_flags & TH_SYN)
end++;
if (th->th_flags & TH_FIN)
end++;
}
if ((th->th_flags & TH_ACK) == 0) {
/* Let it pass through the ack skew check */
ack = dst->seqlo;
} else if ((ack == 0 &&
(th->th_flags & (TH_ACK|TH_RST)) == (TH_ACK|TH_RST)) ||
/* broken tcp stacks do not set ack */
(dst->state < TCPS_SYN_SENT)) {
/*
* Many stacks (ours included) will set the ACK number in an
* FIN|ACK if the SYN times out -- no sequence to ACK.
*/
ack = dst->seqlo;
}
if (seq == end) {
/* Ease sequencing restrictions on no data packets */
seq = src->seqlo;
end = seq;
}
ackskew = dst->seqlo - ack;
/*
* Need to demodulate the sequence numbers in any TCP SACK options
* (Selective ACK). We could optionally validate the SACK values
* against the current ACK window, either forwards or backwards, but
* I'm not confident that SACK has been implemented properly
* everywhere. It wouldn't surprise me if several stacks accidently
* SACK too far backwards of previously ACKed data. There really aren't
* any security implications of bad SACKing unless the target stack
* doesn't validate the option length correctly. Someone trying to
* spoof into a TCP connection won't bother blindly sending SACK
* options anyway.
*/
if (dst->seqdiff && (th->th_off << 2) > sizeof(struct tcphdr)) {
if (pf_modulate_sack(m, off, pd, th, dst))
*copyback = 1;
}
#define MAXACKWINDOW (0xffff + 1500) /* 1500 is an arbitrary fudge factor */
if (SEQ_GEQ(src->seqhi, end) &&
/* Last octet inside other's window space */
SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)) &&
/* Retrans: not more than one window back */
(ackskew >= -MAXACKWINDOW) &&
/* Acking not more than one reassembled fragment backwards */
(ackskew <= (MAXACKWINDOW << sws)) &&
/* Acking not more than one window forward */
((th->th_flags & TH_RST) == 0 || orig_seq == src->seqlo ||
(orig_seq == src->seqlo + 1) || (orig_seq + 1 == src->seqlo) ||
(pd->flags & PFDESC_IP_REAS) == 0)) {
/* Require an exact/+1 sequence match on resets when possible */
if (dst->scrub || src->scrub) {
if (pf_normalize_tcp_stateful(m, off, pd, reason, th,
*state, src, dst, copyback))
return (PF_DROP);
}
/* update max window */
if (src->max_win < win)
src->max_win = win;
/* synchronize sequencing */
if (SEQ_GT(end, src->seqlo))
src->seqlo = end;
/* slide the window of what the other end can send */
if (SEQ_GEQ(ack + (win << sws), dst->seqhi))
dst->seqhi = ack + MAX((win << sws), 1);
/* update states */
if (th->th_flags & TH_SYN)
if (src->state < TCPS_SYN_SENT)
src->state = TCPS_SYN_SENT;
if (th->th_flags & TH_FIN)
if (src->state < TCPS_CLOSING)
src->state = TCPS_CLOSING;
if (th->th_flags & TH_ACK) {
if (dst->state == TCPS_SYN_SENT) {
dst->state = TCPS_ESTABLISHED;
if (src->state == TCPS_ESTABLISHED &&
(*state)->src_node != NULL &&
pf_src_connlimit(state)) {
REASON_SET(reason, PFRES_SRCLIMIT);
return (PF_DROP);
}
} else if (dst->state == TCPS_CLOSING)
dst->state = TCPS_FIN_WAIT_2;
}
if (th->th_flags & TH_RST)
src->state = dst->state = TCPS_TIME_WAIT;
/* update expire time */
(*state)->expire = time_second;
if (src->state >= TCPS_FIN_WAIT_2 &&
dst->state >= TCPS_FIN_WAIT_2)
(*state)->timeout = PFTM_TCP_CLOSED;
else if (src->state >= TCPS_CLOSING &&
dst->state >= TCPS_CLOSING)
(*state)->timeout = PFTM_TCP_FIN_WAIT;
else if (src->state < TCPS_ESTABLISHED ||
dst->state < TCPS_ESTABLISHED)
(*state)->timeout = PFTM_TCP_OPENING;
else if (src->state >= TCPS_CLOSING ||
dst->state >= TCPS_CLOSING)
(*state)->timeout = PFTM_TCP_CLOSING;
else
(*state)->timeout = PFTM_TCP_ESTABLISHED;
/* Fall through to PASS packet */
} else if ((dst->state < TCPS_SYN_SENT ||
dst->state >= TCPS_FIN_WAIT_2 ||
src->state >= TCPS_FIN_WAIT_2) &&
SEQ_GEQ(src->seqhi + MAXACKWINDOW, end) &&
/* Within a window forward of the originating packet */
SEQ_GEQ(seq, src->seqlo - MAXACKWINDOW)) {
/* Within a window backward of the originating packet */
/*
* This currently handles three situations:
* 1) Stupid stacks will shotgun SYNs before their peer
* replies.
* 2) When PF catches an already established stream (the
* firewall rebooted, the state table was flushed, routes
* changed...)
* 3) Packets get funky immediately after the connection
* closes (this should catch Solaris spurious ACK|FINs
* that web servers like to spew after a close)
*
* This must be a little more careful than the above code
* since packet floods will also be caught here. We don't
* update the TTL here to mitigate the damage of a packet
* flood and so the same code can handle awkward establishment
* and a loosened connection close.
* In the establishment case, a correct peer response will
* validate the connection, go through the normal state code
* and keep updating the state TTL.
*/
#ifdef __FreeBSD__
if (V_pf_status.debug >= PF_DEBUG_MISC) {
#else
if (pf_status.debug >= PF_DEBUG_MISC) {
#endif
printf("pf: loose state match: ");
pf_print_state(*state);
pf_print_flags(th->th_flags);
printf(" seq=%u (%u) ack=%u len=%u ackskew=%d "
"pkts=%llu:%llu dir=%s,%s\n", seq, orig_seq, ack,
#ifdef __FreeBSD__
pd->p_len, ackskew, (unsigned long long)(*state)->packets[0],
(unsigned long long)(*state)->packets[1],
#else
pd->p_len, ackskew, (*state)->packets[0],
(*state)->packets[1],
#endif
pd->dir == PF_IN ? "in" : "out",
pd->dir == (*state)->direction ? "fwd" : "rev");
}
if (dst->scrub || src->scrub) {
if (pf_normalize_tcp_stateful(m, off, pd, reason, th,
*state, src, dst, copyback))
return (PF_DROP);
}
/* update max window */
if (src->max_win < win)
src->max_win = win;
/* synchronize sequencing */
if (SEQ_GT(end, src->seqlo))
src->seqlo = end;
/* slide the window of what the other end can send */
if (SEQ_GEQ(ack + (win << sws), dst->seqhi))
dst->seqhi = ack + MAX((win << sws), 1);
/*
* Cannot set dst->seqhi here since this could be a shotgunned
* SYN and not an already established connection.
*/
if (th->th_flags & TH_FIN)
if (src->state < TCPS_CLOSING)
src->state = TCPS_CLOSING;
if (th->th_flags & TH_RST)
src->state = dst->state = TCPS_TIME_WAIT;
/* Fall through to PASS packet */
} else {
if ((*state)->dst.state == TCPS_SYN_SENT &&
(*state)->src.state == TCPS_SYN_SENT) {
/* Send RST for state mismatches during handshake */
if (!(th->th_flags & TH_RST))
#ifdef __FreeBSD__
pf_send_tcp(NULL, (*state)->rule.ptr, pd->af,
#else
pf_send_tcp((*state)->rule.ptr, pd->af,
#endif
pd->dst, pd->src, th->th_dport,
th->th_sport, ntohl(th->th_ack), 0,
TH_RST, 0, 0,
(*state)->rule.ptr->return_ttl, 1, 0,
pd->eh, kif->pfik_ifp);
src->seqlo = 0;
src->seqhi = 1;
src->max_win = 1;
#ifdef __FreeBSD__
} else if (V_pf_status.debug >= PF_DEBUG_MISC) {
#else
} else if (pf_status.debug >= PF_DEBUG_MISC) {
#endif
printf("pf: BAD state: ");
pf_print_state(*state);
pf_print_flags(th->th_flags);
printf(" seq=%u (%u) ack=%u len=%u ackskew=%d "
"pkts=%llu:%llu dir=%s,%s\n",
seq, orig_seq, ack, pd->p_len, ackskew,
#ifdef __FreeBSD__
(unsigned long long)(*state)->packets[0],
(unsigned long long)(*state)->packets[1],
#else
(*state)->packets[0], (*state)->packets[1],
#endif
pd->dir == PF_IN ? "in" : "out",
pd->dir == (*state)->direction ? "fwd" : "rev");
printf("pf: State failure on: %c %c %c %c | %c %c\n",
SEQ_GEQ(src->seqhi, end) ? ' ' : '1',
SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)) ?
' ': '2',
(ackskew >= -MAXACKWINDOW) ? ' ' : '3',
(ackskew <= (MAXACKWINDOW << sws)) ? ' ' : '4',
SEQ_GEQ(src->seqhi + MAXACKWINDOW, end) ?' ' :'5',
SEQ_GEQ(seq, src->seqlo - MAXACKWINDOW) ?' ' :'6');
}
REASON_SET(reason, PFRES_BADSTATE);
return (PF_DROP);
}
return (PF_PASS);
}
int
pf_tcp_track_sloppy(struct pf_state_peer *src, struct pf_state_peer *dst,
struct pf_state **state, struct pf_pdesc *pd, u_short *reason)
{
struct tcphdr *th = pd->hdr.tcp;
if (th->th_flags & TH_SYN)
if (src->state < TCPS_SYN_SENT)
src->state = TCPS_SYN_SENT;
if (th->th_flags & TH_FIN)
if (src->state < TCPS_CLOSING)
src->state = TCPS_CLOSING;
if (th->th_flags & TH_ACK) {
if (dst->state == TCPS_SYN_SENT) {
dst->state = TCPS_ESTABLISHED;
if (src->state == TCPS_ESTABLISHED &&
(*state)->src_node != NULL &&
pf_src_connlimit(state)) {
REASON_SET(reason, PFRES_SRCLIMIT);
return (PF_DROP);
}
} else if (dst->state == TCPS_CLOSING) {
dst->state = TCPS_FIN_WAIT_2;
} else if (src->state == TCPS_SYN_SENT &&
dst->state < TCPS_SYN_SENT) {
/*
* Handle a special sloppy case where we only see one
* half of the connection. If there is a ACK after
* the initial SYN without ever seeing a packet from
* the destination, set the connection to established.
*/
dst->state = src->state = TCPS_ESTABLISHED;
if ((*state)->src_node != NULL &&
pf_src_connlimit(state)) {
REASON_SET(reason, PFRES_SRCLIMIT);
return (PF_DROP);
}
} else if (src->state == TCPS_CLOSING &&
dst->state == TCPS_ESTABLISHED &&
dst->seqlo == 0) {
/*
* Handle the closing of half connections where we
* don't see the full bidirectional FIN/ACK+ACK
* handshake.
*/
dst->state = TCPS_CLOSING;
}
}
if (th->th_flags & TH_RST)
src->state = dst->state = TCPS_TIME_WAIT;
/* update expire time */
(*state)->expire = time_second;
if (src->state >= TCPS_FIN_WAIT_2 &&
dst->state >= TCPS_FIN_WAIT_2)
(*state)->timeout = PFTM_TCP_CLOSED;
else if (src->state >= TCPS_CLOSING &&
dst->state >= TCPS_CLOSING)
(*state)->timeout = PFTM_TCP_FIN_WAIT;
else if (src->state < TCPS_ESTABLISHED ||
dst->state < TCPS_ESTABLISHED)
(*state)->timeout = PFTM_TCP_OPENING;
else if (src->state >= TCPS_CLOSING ||
dst->state >= TCPS_CLOSING)
(*state)->timeout = PFTM_TCP_CLOSING;
else
(*state)->timeout = PFTM_TCP_ESTABLISHED;
return (PF_PASS);
}
int
pf_test_state_tcp(struct pf_state **state, int direction, struct pfi_kif *kif,
struct mbuf *m, int off, void *h, struct pf_pdesc *pd,
u_short *reason)
{
struct pf_state_key_cmp key;
struct tcphdr *th = pd->hdr.tcp;
int copyback = 0;
struct pf_state_peer *src, *dst;
struct pf_state_key *sk;
key.af = pd->af;
key.proto = IPPROTO_TCP;
if (direction == PF_IN) { /* wire side, straight */
PF_ACPY(&key.addr[0], pd->src, key.af);
PF_ACPY(&key.addr[1], pd->dst, key.af);
key.port[0] = th->th_sport;
key.port[1] = th->th_dport;
} else { /* stack side, reverse */
PF_ACPY(&key.addr[1], pd->src, key.af);
PF_ACPY(&key.addr[0], pd->dst, key.af);
key.port[1] = th->th_sport;
key.port[0] = th->th_dport;
}
#ifdef __FreeBSD__
STATE_LOOKUP(kif, &key, direction, *state, m, pd->pf_mtag);
#else
STATE_LOOKUP(kif, &key, direction, *state, m);
#endif
if (direction == (*state)->direction) {
src = &(*state)->src;
dst = &(*state)->dst;
} else {
src = &(*state)->dst;
dst = &(*state)->src;
}
sk = (*state)->key[pd->didx];
if ((*state)->src.state == PF_TCPS_PROXY_SRC) {
if (direction != (*state)->direction) {
REASON_SET(reason, PFRES_SYNPROXY);
return (PF_SYNPROXY_DROP);
}
if (th->th_flags & TH_SYN) {
if (ntohl(th->th_seq) != (*state)->src.seqlo) {
REASON_SET(reason, PFRES_SYNPROXY);
return (PF_DROP);
}
#ifdef __FreeBSD__
pf_send_tcp(NULL, (*state)->rule.ptr, pd->af, pd->dst,
#else
pf_send_tcp((*state)->rule.ptr, pd->af, pd->dst,
#endif
pd->src, th->th_dport, th->th_sport,
(*state)->src.seqhi, ntohl(th->th_seq) + 1,
TH_SYN|TH_ACK, 0, (*state)->src.mss, 0, 1,
0, NULL, NULL);
REASON_SET(reason, PFRES_SYNPROXY);
return (PF_SYNPROXY_DROP);
} else if (!(th->th_flags & TH_ACK) ||
(ntohl(th->th_ack) != (*state)->src.seqhi + 1) ||
(ntohl(th->th_seq) != (*state)->src.seqlo + 1)) {
REASON_SET(reason, PFRES_SYNPROXY);
return (PF_DROP);
} else if ((*state)->src_node != NULL &&
pf_src_connlimit(state)) {
REASON_SET(reason, PFRES_SRCLIMIT);
return (PF_DROP);
} else
(*state)->src.state = PF_TCPS_PROXY_DST;
}
if ((*state)->src.state == PF_TCPS_PROXY_DST) {
if (direction == (*state)->direction) {
if (((th->th_flags & (TH_SYN|TH_ACK)) != TH_ACK) ||
(ntohl(th->th_ack) != (*state)->src.seqhi + 1) ||
(ntohl(th->th_seq) != (*state)->src.seqlo + 1)) {
REASON_SET(reason, PFRES_SYNPROXY);
return (PF_DROP);
}
(*state)->src.max_win = MAX(ntohs(th->th_win), 1);
if ((*state)->dst.seqhi == 1)
(*state)->dst.seqhi = htonl(arc4random());
#ifdef __FreeBSD__
pf_send_tcp(NULL, (*state)->rule.ptr, pd->af,
#else
pf_send_tcp((*state)->rule.ptr, pd->af,
#endif
&sk->addr[pd->sidx], &sk->addr[pd->didx],
sk->port[pd->sidx], sk->port[pd->didx],
(*state)->dst.seqhi, 0, TH_SYN, 0,
(*state)->src.mss, 0, 0, (*state)->tag, NULL, NULL);
REASON_SET(reason, PFRES_SYNPROXY);
return (PF_SYNPROXY_DROP);
} else if (((th->th_flags & (TH_SYN|TH_ACK)) !=
(TH_SYN|TH_ACK)) ||
(ntohl(th->th_ack) != (*state)->dst.seqhi + 1)) {
REASON_SET(reason, PFRES_SYNPROXY);
return (PF_DROP);
} else {
(*state)->dst.max_win = MAX(ntohs(th->th_win), 1);
(*state)->dst.seqlo = ntohl(th->th_seq);
#ifdef __FreeBSD__
pf_send_tcp(NULL, (*state)->rule.ptr, pd->af, pd->dst,
#else
pf_send_tcp((*state)->rule.ptr, pd->af, pd->dst,
#endif
pd->src, th->th_dport, th->th_sport,
ntohl(th->th_ack), ntohl(th->th_seq) + 1,
TH_ACK, (*state)->src.max_win, 0, 0, 0,
(*state)->tag, NULL, NULL);
#ifdef __FreeBSD__
pf_send_tcp(NULL, (*state)->rule.ptr, pd->af,
#else
pf_send_tcp((*state)->rule.ptr, pd->af,
#endif
&sk->addr[pd->sidx], &sk->addr[pd->didx],
sk->port[pd->sidx], sk->port[pd->didx],
(*state)->src.seqhi + 1, (*state)->src.seqlo + 1,
TH_ACK, (*state)->dst.max_win, 0, 0, 1,
0, NULL, NULL);
(*state)->src.seqdiff = (*state)->dst.seqhi -
(*state)->src.seqlo;
(*state)->dst.seqdiff = (*state)->src.seqhi -
(*state)->dst.seqlo;
(*state)->src.seqhi = (*state)->src.seqlo +
(*state)->dst.max_win;
(*state)->dst.seqhi = (*state)->dst.seqlo +
(*state)->src.max_win;
(*state)->src.wscale = (*state)->dst.wscale = 0;
(*state)->src.state = (*state)->dst.state =
TCPS_ESTABLISHED;
REASON_SET(reason, PFRES_SYNPROXY);
return (PF_SYNPROXY_DROP);
}
}
if (((th->th_flags & (TH_SYN|TH_ACK)) == TH_SYN) &&
dst->state >= TCPS_FIN_WAIT_2 &&
src->state >= TCPS_FIN_WAIT_2) {
#ifdef __FreeBSD__
if (V_pf_status.debug >= PF_DEBUG_MISC) {
#else
if (pf_status.debug >= PF_DEBUG_MISC) {
#endif
printf("pf: state reuse ");
pf_print_state(*state);
pf_print_flags(th->th_flags);
printf("\n");
}
/* XXX make sure it's the same direction ?? */
(*state)->src.state = (*state)->dst.state = TCPS_CLOSED;
pf_unlink_state(*state);
*state = NULL;
return (PF_DROP);
}
if ((*state)->state_flags & PFSTATE_SLOPPY) {
if (pf_tcp_track_sloppy(src, dst, state, pd, reason) == PF_DROP)
return (PF_DROP);
} else {
if (pf_tcp_track_full(src, dst, state, kif, m, off, pd, reason,
&copyback) == PF_DROP)
return (PF_DROP);
}
/* translate source/destination address, if necessary */
if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) {
struct pf_state_key *nk = (*state)->key[pd->didx];
if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], pd->af) ||
nk->port[pd->sidx] != th->th_sport)
pf_change_ap(pd->src, &th->th_sport, pd->ip_sum,
&th->th_sum, &nk->addr[pd->sidx],
nk->port[pd->sidx], 0, pd->af);
if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], pd->af) ||
nk->port[pd->didx] != th->th_dport)
pf_change_ap(pd->dst, &th->th_dport, pd->ip_sum,
&th->th_sum, &nk->addr[pd->didx],
nk->port[pd->didx], 0, pd->af);
copyback = 1;
}
/* Copyback sequence modulation or stateful scrub changes if needed */
if (copyback)
#ifdef __FreeBSD__
m_copyback(m, off, sizeof(*th), (caddr_t)th);
#else
m_copyback(m, off, sizeof(*th), th);
#endif
return (PF_PASS);
}
int
pf_test_state_udp(struct pf_state **state, int direction, struct pfi_kif *kif,
struct mbuf *m, int off, void *h, struct pf_pdesc *pd)
{
struct pf_state_peer *src, *dst;
struct pf_state_key_cmp key;
struct udphdr *uh = pd->hdr.udp;
key.af = pd->af;
key.proto = IPPROTO_UDP;
if (direction == PF_IN) { /* wire side, straight */
PF_ACPY(&key.addr[0], pd->src, key.af);
PF_ACPY(&key.addr[1], pd->dst, key.af);
key.port[0] = uh->uh_sport;
key.port[1] = uh->uh_dport;
} else { /* stack side, reverse */
PF_ACPY(&key.addr[1], pd->src, key.af);
PF_ACPY(&key.addr[0], pd->dst, key.af);
key.port[1] = uh->uh_sport;
key.port[0] = uh->uh_dport;
}
#ifdef __FreeBSD__
STATE_LOOKUP(kif, &key, direction, *state, m, pd->pf_mtag);
#else
STATE_LOOKUP(kif, &key, direction, *state, m);
#endif
if (direction == (*state)->direction) {
src = &(*state)->src;
dst = &(*state)->dst;
} else {
src = &(*state)->dst;
dst = &(*state)->src;
}
/* update states */
if (src->state < PFUDPS_SINGLE)
src->state = PFUDPS_SINGLE;
if (dst->state == PFUDPS_SINGLE)
dst->state = PFUDPS_MULTIPLE;
/* update expire time */
(*state)->expire = time_second;
if (src->state == PFUDPS_MULTIPLE && dst->state == PFUDPS_MULTIPLE)
(*state)->timeout = PFTM_UDP_MULTIPLE;
else
(*state)->timeout = PFTM_UDP_SINGLE;
/* translate source/destination address, if necessary */
if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) {
struct pf_state_key *nk = (*state)->key[pd->didx];
if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], pd->af) ||
nk->port[pd->sidx] != uh->uh_sport)
pf_change_ap(pd->src, &uh->uh_sport, pd->ip_sum,
&uh->uh_sum, &nk->addr[pd->sidx],
nk->port[pd->sidx], 1, pd->af);
if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], pd->af) ||
nk->port[pd->didx] != uh->uh_dport)
pf_change_ap(pd->dst, &uh->uh_dport, pd->ip_sum,
&uh->uh_sum, &nk->addr[pd->didx],
nk->port[pd->didx], 1, pd->af);
#ifdef __FreeBSD__
m_copyback(m, off, sizeof(*uh), (caddr_t)uh);
#else
m_copyback(m, off, sizeof(*uh), uh);
#endif
}
return (PF_PASS);
}
int
pf_test_state_icmp(struct pf_state **state, int direction, struct pfi_kif *kif,
struct mbuf *m, int off, void *h, struct pf_pdesc *pd, u_short *reason)
{
struct pf_addr *saddr = pd->src, *daddr = pd->dst;
#ifdef __FreeBSD__
u_int16_t icmpid = 0, *icmpsum;
#else
u_int16_t icmpid, *icmpsum;
#endif
u_int8_t icmptype;
int state_icmp = 0;
struct pf_state_key_cmp key;
switch (pd->proto) {
#ifdef INET
case IPPROTO_ICMP:
icmptype = pd->hdr.icmp->icmp_type;
icmpid = pd->hdr.icmp->icmp_id;
icmpsum = &pd->hdr.icmp->icmp_cksum;
if (icmptype == ICMP_UNREACH ||
icmptype == ICMP_SOURCEQUENCH ||
icmptype == ICMP_REDIRECT ||
icmptype == ICMP_TIMXCEED ||
icmptype == ICMP_PARAMPROB)
state_icmp++;
break;
#endif /* INET */
#ifdef INET6
case IPPROTO_ICMPV6:
icmptype = pd->hdr.icmp6->icmp6_type;
icmpid = pd->hdr.icmp6->icmp6_id;
icmpsum = &pd->hdr.icmp6->icmp6_cksum;
if (icmptype == ICMP6_DST_UNREACH ||
icmptype == ICMP6_PACKET_TOO_BIG ||
icmptype == ICMP6_TIME_EXCEEDED ||
icmptype == ICMP6_PARAM_PROB)
state_icmp++;
break;
#endif /* INET6 */
}
if (!state_icmp) {
/*
* ICMP query/reply message not related to a TCP/UDP packet.
* Search for an ICMP state.
*/
key.af = pd->af;
key.proto = pd->proto;
key.port[0] = key.port[1] = icmpid;
if (direction == PF_IN) { /* wire side, straight */
PF_ACPY(&key.addr[0], pd->src, key.af);
PF_ACPY(&key.addr[1], pd->dst, key.af);
} else { /* stack side, reverse */
PF_ACPY(&key.addr[1], pd->src, key.af);
PF_ACPY(&key.addr[0], pd->dst, key.af);
}
#ifdef __FreeBSD__
STATE_LOOKUP(kif, &key, direction, *state, m, pd->pf_mtag);
#else
STATE_LOOKUP(kif, &key, direction, *state, m);
#endif
(*state)->expire = time_second;
(*state)->timeout = PFTM_ICMP_ERROR_REPLY;
/* translate source/destination address, if necessary */
if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) {
struct pf_state_key *nk = (*state)->key[pd->didx];
switch (pd->af) {
#ifdef INET
case AF_INET:
if (PF_ANEQ(pd->src,
&nk->addr[pd->sidx], AF_INET))
pf_change_a(&saddr->v4.s_addr,
pd->ip_sum,
nk->addr[pd->sidx].v4.s_addr, 0);
if (PF_ANEQ(pd->dst, &nk->addr[pd->didx],
AF_INET))
pf_change_a(&daddr->v4.s_addr,
pd->ip_sum,
nk->addr[pd->didx].v4.s_addr, 0);
if (nk->port[0] !=
pd->hdr.icmp->icmp_id) {
pd->hdr.icmp->icmp_cksum =
pf_cksum_fixup(
pd->hdr.icmp->icmp_cksum, icmpid,
nk->port[pd->sidx], 0);
pd->hdr.icmp->icmp_id =
nk->port[pd->sidx];
}
m_copyback(m, off, ICMP_MINLEN,
#ifdef __FreeBSD__
(caddr_t)
#endif
pd->hdr.icmp);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
if (PF_ANEQ(pd->src,
&nk->addr[pd->sidx], AF_INET6))
pf_change_a6(saddr,
&pd->hdr.icmp6->icmp6_cksum,
&nk->addr[pd->sidx], 0);
if (PF_ANEQ(pd->dst,
&nk->addr[pd->didx], AF_INET6))
pf_change_a6(daddr,
&pd->hdr.icmp6->icmp6_cksum,
&nk->addr[pd->didx], 0);
m_copyback(m, off,
sizeof(struct icmp6_hdr),
#ifdef __FreeBSD__
(caddr_t)
#endif
pd->hdr.icmp6);
break;
#endif /* INET6 */
}
}
return (PF_PASS);
} else {
/*
* ICMP error message in response to a TCP/UDP packet.
* Extract the inner TCP/UDP header and search for that state.
*/
struct pf_pdesc pd2;
#ifdef __FreeBSD__
bzero(&pd2, sizeof pd2);
#endif
#ifdef INET
struct ip h2;
#endif /* INET */
#ifdef INET6
struct ip6_hdr h2_6;
int terminal = 0;
#endif /* INET6 */
#ifdef __FreeBSD__
int ipoff2 = 0;
int off2 = 0;
#else
int ipoff2;
int off2;
#endif
pd2.af = pd->af;
/* Payload packet is from the opposite direction. */
pd2.sidx = (direction == PF_IN) ? 1 : 0;
pd2.didx = (direction == PF_IN) ? 0 : 1;
switch (pd->af) {
#ifdef INET
case AF_INET:
/* offset of h2 in mbuf chain */
ipoff2 = off + ICMP_MINLEN;
if (!pf_pull_hdr(m, ipoff2, &h2, sizeof(h2),
NULL, reason, pd2.af)) {
DPFPRINTF(PF_DEBUG_MISC,
("pf: ICMP error message too short "
"(ip)\n"));
return (PF_DROP);
}
/*
* ICMP error messages don't refer to non-first
* fragments
*/
if (h2.ip_off & htons(IP_OFFMASK)) {
REASON_SET(reason, PFRES_FRAG);
return (PF_DROP);
}
/* offset of protocol header that follows h2 */
off2 = ipoff2 + (h2.ip_hl << 2);
pd2.proto = h2.ip_p;
pd2.src = (struct pf_addr *)&h2.ip_src;
pd2.dst = (struct pf_addr *)&h2.ip_dst;
pd2.ip_sum = &h2.ip_sum;
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
ipoff2 = off + sizeof(struct icmp6_hdr);
if (!pf_pull_hdr(m, ipoff2, &h2_6, sizeof(h2_6),
NULL, reason, pd2.af)) {
DPFPRINTF(PF_DEBUG_MISC,
("pf: ICMP error message too short "
"(ip6)\n"));
return (PF_DROP);
}
pd2.proto = h2_6.ip6_nxt;
pd2.src = (struct pf_addr *)&h2_6.ip6_src;
pd2.dst = (struct pf_addr *)&h2_6.ip6_dst;
pd2.ip_sum = NULL;
off2 = ipoff2 + sizeof(h2_6);
do {
switch (pd2.proto) {
case IPPROTO_FRAGMENT:
/*
* ICMPv6 error messages for
* non-first fragments
*/
REASON_SET(reason, PFRES_FRAG);
return (PF_DROP);
case IPPROTO_AH:
case IPPROTO_HOPOPTS:
case IPPROTO_ROUTING:
case IPPROTO_DSTOPTS: {
/* get next header and header length */
struct ip6_ext opt6;
if (!pf_pull_hdr(m, off2, &opt6,
sizeof(opt6), NULL, reason,
pd2.af)) {
DPFPRINTF(PF_DEBUG_MISC,
("pf: ICMPv6 short opt\n"));
return (PF_DROP);
}
if (pd2.proto == IPPROTO_AH)
off2 += (opt6.ip6e_len + 2) * 4;
else
off2 += (opt6.ip6e_len + 1) * 8;
pd2.proto = opt6.ip6e_nxt;
/* goto the next header */
break;
}
default:
terminal++;
break;
}
} while (!terminal);
break;
#endif /* INET6 */
}
switch (pd2.proto) {
case IPPROTO_TCP: {
struct tcphdr th;
u_int32_t seq;
struct pf_state_peer *src, *dst;
u_int8_t dws;
int copyback = 0;
/*
* Only the first 8 bytes of the TCP header can be
* expected. Don't access any TCP header fields after
* th_seq, an ackskew test is not possible.
*/
if (!pf_pull_hdr(m, off2, &th, 8, NULL, reason,
pd2.af)) {
DPFPRINTF(PF_DEBUG_MISC,
("pf: ICMP error message too short "
"(tcp)\n"));
return (PF_DROP);
}
key.af = pd2.af;
key.proto = IPPROTO_TCP;
PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
key.port[pd2.sidx] = th.th_sport;
key.port[pd2.didx] = th.th_dport;
#ifdef __FreeBSD__
STATE_LOOKUP(kif, &key, direction, *state, m, pd->pf_mtag);
#else
STATE_LOOKUP(kif, &key, direction, *state, m);
#endif
if (direction == (*state)->direction) {
src = &(*state)->dst;
dst = &(*state)->src;
} else {
src = &(*state)->src;
dst = &(*state)->dst;
}
if (src->wscale && dst->wscale)
dws = dst->wscale & PF_WSCALE_MASK;
else
dws = 0;
/* Demodulate sequence number */
seq = ntohl(th.th_seq) - src->seqdiff;
if (src->seqdiff) {
pf_change_a(&th.th_seq, icmpsum,
htonl(seq), 0);
copyback = 1;
}
if (!((*state)->state_flags & PFSTATE_SLOPPY) &&
(!SEQ_GEQ(src->seqhi, seq) ||
!SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)))) {
#ifdef __FreeBSD__
if (V_pf_status.debug >= PF_DEBUG_MISC) {
#else
if (pf_status.debug >= PF_DEBUG_MISC) {
#endif
printf("pf: BAD ICMP %d:%d ",
icmptype, pd->hdr.icmp->icmp_code);
pf_print_host(pd->src, 0, pd->af);
printf(" -> ");
pf_print_host(pd->dst, 0, pd->af);
printf(" state: ");
pf_print_state(*state);
printf(" seq=%u\n", seq);
}
REASON_SET(reason, PFRES_BADSTATE);
return (PF_DROP);
} else {
#ifdef __FreeBSD__
if (V_pf_status.debug >= PF_DEBUG_MISC) {
#else
if (pf_status.debug >= PF_DEBUG_MISC) {
#endif
printf("pf: OK ICMP %d:%d ",
icmptype, pd->hdr.icmp->icmp_code);
pf_print_host(pd->src, 0, pd->af);
printf(" -> ");
pf_print_host(pd->dst, 0, pd->af);
printf(" state: ");
pf_print_state(*state);
printf(" seq=%u\n", seq);
}
}
/* translate source/destination address, if necessary */
if ((*state)->key[PF_SK_WIRE] !=
(*state)->key[PF_SK_STACK]) {
struct pf_state_key *nk =
(*state)->key[pd->didx];
if (PF_ANEQ(pd2.src,
&nk->addr[pd2.sidx], pd2.af) ||
nk->port[pd2.sidx] != th.th_sport)
pf_change_icmp(pd2.src, &th.th_sport,
daddr, &nk->addr[pd2.sidx],
nk->port[pd2.sidx], NULL,
pd2.ip_sum, icmpsum,
pd->ip_sum, 0, pd2.af);
if (PF_ANEQ(pd2.dst,
&nk->addr[pd2.didx], pd2.af) ||
nk->port[pd2.didx] != th.th_dport)
pf_change_icmp(pd2.dst, &th.th_dport,
NULL, /* XXX Inbound NAT? */
&nk->addr[pd2.didx],
nk->port[pd2.didx], NULL,
pd2.ip_sum, icmpsum,
pd->ip_sum, 0, pd2.af);
copyback = 1;
}
if (copyback) {
switch (pd2.af) {
#ifdef INET
case AF_INET:
m_copyback(m, off, ICMP_MINLEN,
#ifdef __FreeBSD__
(caddr_t)
#endif
pd->hdr.icmp);
m_copyback(m, ipoff2, sizeof(h2),
#ifdef __FreeBSD__
(caddr_t)
#endif
&h2);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
m_copyback(m, off,
sizeof(struct icmp6_hdr),
#ifdef __FreeBSD__
(caddr_t)
#endif
pd->hdr.icmp6);
m_copyback(m, ipoff2, sizeof(h2_6),
#ifdef __FreeBSD__
(caddr_t)
#endif
&h2_6);
break;
#endif /* INET6 */
}
#ifdef __FreeBSD__
m_copyback(m, off2, 8, (caddr_t)&th);
#else
m_copyback(m, off2, 8, &th);
#endif
}
return (PF_PASS);
break;
}
case IPPROTO_UDP: {
struct udphdr uh;
if (!pf_pull_hdr(m, off2, &uh, sizeof(uh),
NULL, reason, pd2.af)) {
DPFPRINTF(PF_DEBUG_MISC,
("pf: ICMP error message too short "
"(udp)\n"));
return (PF_DROP);
}
key.af = pd2.af;
key.proto = IPPROTO_UDP;
PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
key.port[pd2.sidx] = uh.uh_sport;
key.port[pd2.didx] = uh.uh_dport;
#ifdef __FreeBSD__
STATE_LOOKUP(kif, &key, direction, *state, m, pd->pf_mtag);
#else
STATE_LOOKUP(kif, &key, direction, *state, m);
#endif
/* translate source/destination address, if necessary */
if ((*state)->key[PF_SK_WIRE] !=
(*state)->key[PF_SK_STACK]) {
struct pf_state_key *nk =
(*state)->key[pd->didx];
if (PF_ANEQ(pd2.src,
&nk->addr[pd2.sidx], pd2.af) ||
nk->port[pd2.sidx] != uh.uh_sport)
pf_change_icmp(pd2.src, &uh.uh_sport,
daddr, &nk->addr[pd2.sidx],
nk->port[pd2.sidx], &uh.uh_sum,
pd2.ip_sum, icmpsum,
pd->ip_sum, 1, pd2.af);
if (PF_ANEQ(pd2.dst,
&nk->addr[pd2.didx], pd2.af) ||
nk->port[pd2.didx] != uh.uh_dport)
pf_change_icmp(pd2.dst, &uh.uh_dport,
NULL, /* XXX Inbound NAT? */
&nk->addr[pd2.didx],
nk->port[pd2.didx], &uh.uh_sum,
pd2.ip_sum, icmpsum,
pd->ip_sum, 1, pd2.af);
switch (pd2.af) {
#ifdef INET
case AF_INET:
m_copyback(m, off, ICMP_MINLEN,
#ifdef __FreeBSD__
(caddr_t)
#endif
pd->hdr.icmp);
#ifdef __FreeBSD__
m_copyback(m, ipoff2, sizeof(h2), (caddr_t)&h2);
#else
m_copyback(m, ipoff2, sizeof(h2), &h2);
#endif
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
m_copyback(m, off,
sizeof(struct icmp6_hdr),
#ifdef __FreeBSD__
(caddr_t)
#endif
pd->hdr.icmp6);
m_copyback(m, ipoff2, sizeof(h2_6),
#ifdef __FreeBSD__
(caddr_t)
#endif
&h2_6);
break;
#endif /* INET6 */
}
#ifdef __FreeBSD__
m_copyback(m, off2, sizeof(uh), (caddr_t)&uh);
#else
m_copyback(m, off2, sizeof(uh), &uh);
#endif
}
return (PF_PASS);
break;
}
#ifdef INET
case IPPROTO_ICMP: {
struct icmp iih;
if (!pf_pull_hdr(m, off2, &iih, ICMP_MINLEN,
NULL, reason, pd2.af)) {
DPFPRINTF(PF_DEBUG_MISC,
("pf: ICMP error message too short i"
"(icmp)\n"));
return (PF_DROP);
}
key.af = pd2.af;
key.proto = IPPROTO_ICMP;
PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
key.port[0] = key.port[1] = iih.icmp_id;
#ifdef __FreeBSD__
STATE_LOOKUP(kif, &key, direction, *state, m, pd->pf_mtag);
#else
STATE_LOOKUP(kif, &key, direction, *state, m);
#endif
/* translate source/destination address, if necessary */
if ((*state)->key[PF_SK_WIRE] !=
(*state)->key[PF_SK_STACK]) {
struct pf_state_key *nk =
(*state)->key[pd->didx];
if (PF_ANEQ(pd2.src,
&nk->addr[pd2.sidx], pd2.af) ||
nk->port[pd2.sidx] != iih.icmp_id)
pf_change_icmp(pd2.src, &iih.icmp_id,
daddr, &nk->addr[pd2.sidx],
nk->port[pd2.sidx], NULL,
pd2.ip_sum, icmpsum,
pd->ip_sum, 0, AF_INET);
if (PF_ANEQ(pd2.dst,
&nk->addr[pd2.didx], pd2.af) ||
nk->port[pd2.didx] != iih.icmp_id)
pf_change_icmp(pd2.dst, &iih.icmp_id,
NULL, /* XXX Inbound NAT? */
&nk->addr[pd2.didx],
nk->port[pd2.didx], NULL,
pd2.ip_sum, icmpsum,
pd->ip_sum, 0, AF_INET);
#ifdef __FreeBSD__
m_copyback(m, off, ICMP_MINLEN, (caddr_t)pd->hdr.icmp);
m_copyback(m, ipoff2, sizeof(h2), (caddr_t)&h2);
m_copyback(m, off2, ICMP_MINLEN, (caddr_t)&iih);
#else
m_copyback(m, off, ICMP_MINLEN, pd->hdr.icmp);
m_copyback(m, ipoff2, sizeof(h2), &h2);
m_copyback(m, off2, ICMP_MINLEN, &iih);
#endif
}
return (PF_PASS);
break;
}
#endif /* INET */
#ifdef INET6
case IPPROTO_ICMPV6: {
struct icmp6_hdr iih;
if (!pf_pull_hdr(m, off2, &iih,
sizeof(struct icmp6_hdr), NULL, reason, pd2.af)) {
DPFPRINTF(PF_DEBUG_MISC,
("pf: ICMP error message too short "
"(icmp6)\n"));
return (PF_DROP);
}
key.af = pd2.af;
key.proto = IPPROTO_ICMPV6;
PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
key.port[0] = key.port[1] = iih.icmp6_id;
#ifdef __FreeBSD__
STATE_LOOKUP(kif, &key, direction, *state, m, pd->pf_mtag);
#else
STATE_LOOKUP(kif, &key, direction, *state, m);
#endif
/* translate source/destination address, if necessary */
if ((*state)->key[PF_SK_WIRE] !=
(*state)->key[PF_SK_STACK]) {
struct pf_state_key *nk =
(*state)->key[pd->didx];
if (PF_ANEQ(pd2.src,
&nk->addr[pd2.sidx], pd2.af) ||
nk->port[pd2.sidx] != iih.icmp6_id)
pf_change_icmp(pd2.src, &iih.icmp6_id,
daddr, &nk->addr[pd2.sidx],
nk->port[pd2.sidx], NULL,
pd2.ip_sum, icmpsum,
pd->ip_sum, 0, AF_INET6);
if (PF_ANEQ(pd2.dst,
&nk->addr[pd2.didx], pd2.af) ||
nk->port[pd2.didx] != iih.icmp6_id)
pf_change_icmp(pd2.dst, &iih.icmp6_id,
NULL, /* XXX Inbound NAT? */
&nk->addr[pd2.didx],
nk->port[pd2.didx], NULL,
pd2.ip_sum, icmpsum,
pd->ip_sum, 0, AF_INET6);
#ifdef __FreeBSD__
m_copyback(m, off, sizeof(struct icmp6_hdr),
(caddr_t)pd->hdr.icmp6);
m_copyback(m, ipoff2, sizeof(h2_6), (caddr_t)&h2_6);
m_copyback(m, off2, sizeof(struct icmp6_hdr),
(caddr_t)&iih);
#else
m_copyback(m, off, sizeof(struct icmp6_hdr),
pd->hdr.icmp6);
m_copyback(m, ipoff2, sizeof(h2_6), &h2_6);
m_copyback(m, off2, sizeof(struct icmp6_hdr),
&iih);
#endif
}
return (PF_PASS);
break;
}
#endif /* INET6 */
default: {
key.af = pd2.af;
key.proto = pd2.proto;
PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
key.port[0] = key.port[1] = 0;
#ifdef __FreeBSD__
STATE_LOOKUP(kif, &key, direction, *state, m, pd->pf_mtag);
#else
STATE_LOOKUP(kif, &key, direction, *state, m);
#endif
/* translate source/destination address, if necessary */
if ((*state)->key[PF_SK_WIRE] !=
(*state)->key[PF_SK_STACK]) {
struct pf_state_key *nk =
(*state)->key[pd->didx];
if (PF_ANEQ(pd2.src,
&nk->addr[pd2.sidx], pd2.af))
pf_change_icmp(pd2.src, NULL, daddr,
&nk->addr[pd2.sidx], 0, NULL,
pd2.ip_sum, icmpsum,
pd->ip_sum, 0, pd2.af);
if (PF_ANEQ(pd2.dst,
&nk->addr[pd2.didx], pd2.af))
pf_change_icmp(pd2.src, NULL,
NULL, /* XXX Inbound NAT? */
&nk->addr[pd2.didx], 0, NULL,
pd2.ip_sum, icmpsum,
pd->ip_sum, 0, pd2.af);
switch (pd2.af) {
#ifdef INET
case AF_INET:
#ifdef __FreeBSD__
m_copyback(m, off, ICMP_MINLEN,
(caddr_t)pd->hdr.icmp);
m_copyback(m, ipoff2, sizeof(h2), (caddr_t)&h2);
#else
m_copyback(m, off, ICMP_MINLEN,
pd->hdr.icmp);
m_copyback(m, ipoff2, sizeof(h2), &h2);
#endif
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
m_copyback(m, off,
sizeof(struct icmp6_hdr),
#ifdef __FreeBSD__
(caddr_t)
#endif
pd->hdr.icmp6);
m_copyback(m, ipoff2, sizeof(h2_6),
#ifdef __FreeBSD__
(caddr_t)
#endif
&h2_6);
break;
#endif /* INET6 */
}
}
return (PF_PASS);
break;
}
}
}
}
int
pf_test_state_other(struct pf_state **state, int direction, struct pfi_kif *kif,
struct mbuf *m, struct pf_pdesc *pd)
{
struct pf_state_peer *src, *dst;
struct pf_state_key_cmp key;
key.af = pd->af;
key.proto = pd->proto;
if (direction == PF_IN) {
PF_ACPY(&key.addr[0], pd->src, key.af);
PF_ACPY(&key.addr[1], pd->dst, key.af);
key.port[0] = key.port[1] = 0;
} else {
PF_ACPY(&key.addr[1], pd->src, key.af);
PF_ACPY(&key.addr[0], pd->dst, key.af);
key.port[1] = key.port[0] = 0;
}
#ifdef __FreeBSD__
STATE_LOOKUP(kif, &key, direction, *state, m, pd->pf_mtag);
#else
STATE_LOOKUP(kif, &key, direction, *state, m);
#endif
if (direction == (*state)->direction) {
src = &(*state)->src;
dst = &(*state)->dst;
} else {
src = &(*state)->dst;
dst = &(*state)->src;
}
/* update states */
if (src->state < PFOTHERS_SINGLE)
src->state = PFOTHERS_SINGLE;
if (dst->state == PFOTHERS_SINGLE)
dst->state = PFOTHERS_MULTIPLE;
/* update expire time */
(*state)->expire = time_second;
if (src->state == PFOTHERS_MULTIPLE && dst->state == PFOTHERS_MULTIPLE)
(*state)->timeout = PFTM_OTHER_MULTIPLE;
else
(*state)->timeout = PFTM_OTHER_SINGLE;
/* translate source/destination address, if necessary */
if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) {
struct pf_state_key *nk = (*state)->key[pd->didx];
#ifdef __FreeBSD__
KASSERT(nk, ("%s: nk is null", __FUNCTION__));
KASSERT(pd, ("%s: pd is null", __FUNCTION__));
KASSERT(pd->src, ("%s: pd->src is null", __FUNCTION__));
KASSERT(pd->dst, ("%s: pd->dst is null", __FUNCTION__));
#else
KASSERT(nk);
KASSERT(pd);
KASSERT(pd->src);
KASSERT(pd->dst);
#endif
switch (pd->af) {
#ifdef INET
case AF_INET:
if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], AF_INET))
pf_change_a(&pd->src->v4.s_addr,
pd->ip_sum,
nk->addr[pd->sidx].v4.s_addr,
0);
if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], AF_INET))
pf_change_a(&pd->dst->v4.s_addr,
pd->ip_sum,
nk->addr[pd->didx].v4.s_addr,
0);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], AF_INET))
PF_ACPY(pd->src, &nk->addr[pd->sidx], pd->af);
if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], AF_INET))
PF_ACPY(pd->dst, &nk->addr[pd->didx], pd->af);
#endif /* INET6 */
}
}
return (PF_PASS);
}
/*
* ipoff and off are measured from the start of the mbuf chain.
* h must be at "ipoff" on the mbuf chain.
*/
void *
pf_pull_hdr(struct mbuf *m, int off, void *p, int len,
u_short *actionp, u_short *reasonp, sa_family_t af)
{
switch (af) {
#ifdef INET
case AF_INET: {
struct ip *h = mtod(m, struct ip *);
u_int16_t fragoff = (ntohs(h->ip_off) & IP_OFFMASK) << 3;
if (fragoff) {
if (fragoff >= len)
ACTION_SET(actionp, PF_PASS);
else {
ACTION_SET(actionp, PF_DROP);
REASON_SET(reasonp, PFRES_FRAG);
}
return (NULL);
}
if (m->m_pkthdr.len < off + len ||
ntohs(h->ip_len) < off + len) {
ACTION_SET(actionp, PF_DROP);
REASON_SET(reasonp, PFRES_SHORT);
return (NULL);
}
break;
}
#endif /* INET */
#ifdef INET6
case AF_INET6: {
struct ip6_hdr *h = mtod(m, struct ip6_hdr *);
if (m->m_pkthdr.len < off + len ||
(ntohs(h->ip6_plen) + sizeof(struct ip6_hdr)) <
(unsigned)(off + len)) {
ACTION_SET(actionp, PF_DROP);
REASON_SET(reasonp, PFRES_SHORT);
return (NULL);
}
break;
}
#endif /* INET6 */
}
m_copydata(m, off, len, p);
return (p);
}
int
pf_routable(struct pf_addr *addr, sa_family_t af, struct pfi_kif *kif)
{
#ifdef __FreeBSD__
#ifdef RADIX_MPATH
struct radix_node_head *rnh;
#endif
#endif
struct sockaddr_in *dst;
int ret = 1;
int check_mpath;
#ifndef __FreeBSD__
extern int ipmultipath;
#endif
#ifdef INET6
#ifndef __FreeBSD__
extern int ip6_multipath;
#endif
struct sockaddr_in6 *dst6;
struct route_in6 ro;
#else
struct route ro;
#endif
struct radix_node *rn;
struct rtentry *rt;
struct ifnet *ifp;
check_mpath = 0;
#ifdef __FreeBSD__
#ifdef RADIX_MPATH
/* XXX: stick to table 0 for now */
rnh = rt_tables_get_rnh(0, af);
if (rnh != NULL && rn_mpath_capable(rnh))
check_mpath = 1;
#endif
#endif
bzero(&ro, sizeof(ro));
switch (af) {
case AF_INET:
dst = satosin(&ro.ro_dst);
dst->sin_family = AF_INET;
dst->sin_len = sizeof(*dst);
dst->sin_addr = addr->v4;
#ifndef __FreeBSD__
if (ipmultipath)
check_mpath = 1;
#endif
break;
#ifdef INET6
case AF_INET6:
/*
* Skip check for addresses with embedded interface scope,
* as they would always match anyway.
*/
if (IN6_IS_SCOPE_EMBED(&addr->v6))
goto out;
dst6 = (struct sockaddr_in6 *)&ro.ro_dst;
dst6->sin6_family = AF_INET6;
dst6->sin6_len = sizeof(*dst6);
dst6->sin6_addr = addr->v6;
#ifndef __FreeBSD__
if (ip6_multipath)
check_mpath = 1;
#endif
break;
#endif /* INET6 */
default:
return (0);
}
/* Skip checks for ipsec interfaces */
if (kif != NULL && kif->pfik_ifp->if_type == IFT_ENC)
goto out;
#ifdef __FreeBSD__
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
/* XXX MRT not always INET */ /* stick with table 0 though */
#ifdef INET
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
if (af == AF_INET)
in_rtalloc_ign((struct route *)&ro, 0, 0);
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
else
#endif
rtalloc_ign((struct route *)&ro, 0);
#else /* ! __FreeBSD__ */
rtalloc_noclone((struct route *)&ro, NO_CLONING);
#endif
if (ro.ro_rt != NULL) {
/* No interface given, this is a no-route check */
if (kif == NULL)
goto out;
if (kif->pfik_ifp == NULL) {
ret = 0;
goto out;
}
/* Perform uRPF check if passed input interface */
ret = 0;
rn = (struct radix_node *)ro.ro_rt;
do {
rt = (struct rtentry *)rn;
#ifndef __FreeBSD__ /* CARPDEV */
if (rt->rt_ifp->if_type == IFT_CARP)
ifp = rt->rt_ifp->if_carpdev;
else
#endif
ifp = rt->rt_ifp;
if (kif->pfik_ifp == ifp)
ret = 1;
#ifdef __FreeBSD__
#ifdef RADIX_MPATH
rn = rn_mpath_next(rn);
#endif
#else
rn = rn_mpath_next(rn, 0);
#endif
} while (check_mpath == 1 && rn != NULL && ret == 0);
} else
ret = 0;
out:
if (ro.ro_rt != NULL)
RTFREE(ro.ro_rt);
return (ret);
}
int
pf_rtlabel_match(struct pf_addr *addr, sa_family_t af, struct pf_addr_wrap *aw)
{
struct sockaddr_in *dst;
#ifdef INET6
struct sockaddr_in6 *dst6;
struct route_in6 ro;
#else
struct route ro;
#endif
int ret = 0;
bzero(&ro, sizeof(ro));
switch (af) {
case AF_INET:
dst = satosin(&ro.ro_dst);
dst->sin_family = AF_INET;
dst->sin_len = sizeof(*dst);
dst->sin_addr = addr->v4;
break;
#ifdef INET6
case AF_INET6:
dst6 = (struct sockaddr_in6 *)&ro.ro_dst;
dst6->sin6_family = AF_INET6;
dst6->sin6_len = sizeof(*dst6);
dst6->sin6_addr = addr->v6;
break;
#endif /* INET6 */
default:
return (0);
}
#ifdef __FreeBSD__
# ifdef RTF_PRCLONING
rtalloc_ign((struct route *)&ro, (RTF_CLONING|RTF_PRCLONING));
# else /* !RTF_PRCLONING */
#ifdef INET
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
if (af == AF_INET)
in_rtalloc_ign((struct route *)&ro, 0, 0);
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
else
#endif
rtalloc_ign((struct route *)&ro, 0);
# endif
#else /* ! __FreeBSD__ */
rtalloc_noclone((struct route *)&ro, NO_CLONING);
#endif
if (ro.ro_rt != NULL) {
#ifdef __FreeBSD__
/* XXX_IMPORT: later */
#else
if (ro.ro_rt->rt_labelid == aw->v.rtlabel)
ret = 1;
#endif
RTFREE(ro.ro_rt);
}
return (ret);
}
#ifdef INET
void
pf_route(struct mbuf **m, struct pf_rule *r, int dir, struct ifnet *oifp,
struct pf_state *s, struct pf_pdesc *pd)
{
struct mbuf *m0, *m1;
struct route iproute;
struct route *ro = NULL;
struct sockaddr_in *dst;
struct ip *ip;
struct ifnet *ifp = NULL;
struct pf_addr naddr;
struct pf_src_node *sn = NULL;
int error = 0;
#ifdef __FreeBSD__
int sw_csum;
#endif
#ifdef IPSEC
struct m_tag *mtag;
#endif /* IPSEC */
if (m == NULL || *m == NULL || r == NULL ||
(dir != PF_IN && dir != PF_OUT) || oifp == NULL)
panic("pf_route: invalid parameters");
#ifdef __FreeBSD__
if (pd->pf_mtag->routed++ > 3) {
#else
if ((*m)->m_pkthdr.pf.routed++ > 3) {
#endif
m0 = *m;
*m = NULL;
goto bad;
}
if (r->rt == PF_DUPTO) {
#ifdef __FreeBSD__
if ((m0 = m_dup(*m, M_DONTWAIT)) == NULL)
#else
if ((m0 = m_copym2(*m, 0, M_COPYALL, M_NOWAIT)) == NULL)
#endif
return;
} else {
if ((r->rt == PF_REPLYTO) == (r->direction == dir))
return;
m0 = *m;
}
if (m0->m_len < sizeof(struct ip)) {
DPFPRINTF(PF_DEBUG_URGENT,
("pf_route: m0->m_len < sizeof(struct ip)\n"));
goto bad;
}
ip = mtod(m0, struct ip *);
ro = &iproute;
bzero((caddr_t)ro, sizeof(*ro));
dst = satosin(&ro->ro_dst);
dst->sin_family = AF_INET;
dst->sin_len = sizeof(*dst);
dst->sin_addr = ip->ip_dst;
if (r->rt == PF_FASTROUTE) {
#ifdef __FreeBSD__
Add code to allow the system to handle multiple routing tables. This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
in_rtalloc(ro, 0);
#else
rtalloc(ro);
#endif
if (ro->ro_rt == 0) {
#ifdef __FreeBSD__
KMOD_IPSTAT_INC(ips_noroute);
#else
ipstat.ips_noroute++;
#endif
goto bad;
}
ifp = ro->ro_rt->rt_ifp;
ro->ro_rt->rt_use++;
if (ro->ro_rt->rt_flags & RTF_GATEWAY)
dst = satosin(ro->ro_rt->rt_gateway);
} else {
if (TAILQ_EMPTY(&r->rpool.list)) {
DPFPRINTF(PF_DEBUG_URGENT,
("pf_route: TAILQ_EMPTY(&r->rpool.list)\n"));
goto bad;
}
if (s == NULL) {
pf_map_addr(AF_INET, r, (struct pf_addr *)&ip->ip_src,
&naddr, NULL, &sn);
if (!PF_AZERO(&naddr, AF_INET))
dst->sin_addr.s_addr = naddr.v4.s_addr;
ifp = r->rpool.cur->kif ?
r->rpool.cur->kif->pfik_ifp : NULL;
} else {
if (!PF_AZERO(&s->rt_addr, AF_INET))
dst->sin_addr.s_addr =
s->rt_addr.v4.s_addr;
ifp = s->rt_kif ? s->rt_kif->pfik_ifp : NULL;
}
}
if (ifp == NULL)
goto bad;
if (oifp != ifp) {
#ifdef __FreeBSD__
PF_UNLOCK();
if (pf_test(PF_OUT, ifp, &m0, NULL, NULL) != PF_PASS) {
PF_LOCK();
goto bad;
} else if (m0 == NULL) {
PF_LOCK();
goto done;
}
PF_LOCK();
#else
if (pf_test(PF_OUT, ifp, &m0, NULL) != PF_PASS)
goto bad;
else if (m0 == NULL)
goto done;
#endif
if (m0->m_len < sizeof(struct ip)) {
DPFPRINTF(PF_DEBUG_URGENT,
("pf_route: m0->m_len < sizeof(struct ip)\n"));
goto bad;
}
ip = mtod(m0, struct ip *);
}
#ifdef __FreeBSD__
/* Copied from FreeBSD 5.1-CURRENT ip_output. */
m0->m_pkthdr.csum_flags |= CSUM_IP;
sw_csum = m0->m_pkthdr.csum_flags & ~ifp->if_hwassist;
if (sw_csum & CSUM_DELAY_DATA) {
/*
* XXX: in_delayed_cksum assumes HBO for ip->ip_len (at least)
*/
NTOHS(ip->ip_len);
NTOHS(ip->ip_off); /* XXX: needed? */
in_delayed_cksum(m0);
HTONS(ip->ip_len);
HTONS(ip->ip_off);
sw_csum &= ~CSUM_DELAY_DATA;
}
m0->m_pkthdr.csum_flags &= ifp->if_hwassist;
if (ntohs(ip->ip_len) <= ifp->if_mtu ||
(ifp->if_hwassist & CSUM_FRAGMENT &&
((ip->ip_off & htons(IP_DF)) == 0))) {
/*
* ip->ip_len = htons(ip->ip_len);
* ip->ip_off = htons(ip->ip_off);
*/
ip->ip_sum = 0;
if (sw_csum & CSUM_DELAY_IP) {
/* From KAME */
if (ip->ip_v == IPVERSION &&
(ip->ip_hl << 2) == sizeof(*ip)) {
ip->ip_sum = in_cksum_hdr(ip);
} else {
ip->ip_sum = in_cksum(m0, ip->ip_hl << 2);
}
}
PF_UNLOCK();
error = (*ifp->if_output)(ifp, m0, sintosa(dst), ro);
PF_LOCK();
goto done;
}
#else
/* Copied from ip_output. */
#ifdef IPSEC
/*
* If deferred crypto processing is needed, check that the
* interface supports it.
*/
if ((mtag = m_tag_find(m0, PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED, NULL))
!= NULL && (ifp->if_capabilities & IFCAP_IPSEC) == 0) {
/* Notify IPsec to do its own crypto. */
ipsp_skipcrypto_unmark((struct tdb_ident *)(mtag + 1));
goto bad;
}
#endif /* IPSEC */
/* Catch routing changes wrt. hardware checksumming for TCP or UDP. */
if (m0->m_pkthdr.csum_flags & M_TCPV4_CSUM_OUT) {
if (!(ifp->if_capabilities & IFCAP_CSUM_TCPv4) ||
ifp->if_bridge != NULL) {
in_delayed_cksum(m0);
m0->m_pkthdr.csum_flags &= ~M_TCPV4_CSUM_OUT; /* Clr */
}
} else if (m0->m_pkthdr.csum_flags & M_UDPV4_CSUM_OUT) {
if (!(ifp->if_capabilities & IFCAP_CSUM_UDPv4) ||
ifp->if_bridge != NULL) {
in_delayed_cksum(m0);
m0->m_pkthdr.csum_flags &= ~M_UDPV4_CSUM_OUT; /* Clr */
}
}
if (ntohs(ip->ip_len) <= ifp->if_mtu) {
ip->ip_sum = 0;
if ((ifp->if_capabilities & IFCAP_CSUM_IPv4) &&
ifp->if_bridge == NULL) {
m0->m_pkthdr.csum_flags |= M_IPV4_CSUM_OUT;
#ifdef __FreeBSD__
KMOD_IPSTAT_INC(ips_outhwcsum);
#else
ipstat.ips_outhwcsum++;
#endif
} else
ip->ip_sum = in_cksum(m0, ip->ip_hl << 2);
/* Update relevant hardware checksum stats for TCP/UDP */
if (m0->m_pkthdr.csum_flags & M_TCPV4_CSUM_OUT)
KMOD_TCPSTAT_INC(tcps_outhwcsum);
else if (m0->m_pkthdr.csum_flags & M_UDPV4_CSUM_OUT)
KMOD_UDPSTAT_INC(udps_outhwcsum);
error = (*ifp->if_output)(ifp, m0, sintosa(dst), NULL);
goto done;
}
#endif
/*
* Too large for interface; fragment if possible.
* Must be able to put at least 8 bytes per fragment.
*/
if (ip->ip_off & htons(IP_DF)) {
#ifdef __FreeBSD__
KMOD_IPSTAT_INC(ips_cantfrag);
#else
ipstat.ips_cantfrag++;
#endif
if (r->rt != PF_DUPTO) {
#ifdef __FreeBSD__
/* icmp_error() expects host byte ordering */
NTOHS(ip->ip_len);
NTOHS(ip->ip_off);
PF_UNLOCK();
icmp_error(m0, ICMP_UNREACH, ICMP_UNREACH_NEEDFRAG, 0,
2005-05-04 19:51:06 +00:00
ifp->if_mtu);
PF_LOCK();
#else
icmp_error(m0, ICMP_UNREACH, ICMP_UNREACH_NEEDFRAG, 0,
ifp->if_mtu);
#endif
goto done;
} else
goto bad;
}
m1 = m0;
#ifdef __FreeBSD__
/*
* XXX: is cheaper + less error prone than own function
*/
NTOHS(ip->ip_len);
NTOHS(ip->ip_off);
error = ip_fragment(ip, &m0, ifp->if_mtu, ifp->if_hwassist, sw_csum);
#else
error = ip_fragment(m0, ifp, ifp->if_mtu);
#endif
if (error) {
#ifndef __FreeBSD__ /* ip_fragment does not do m_freem() on FreeBSD */
m0 = NULL;
#endif
goto bad;
}
for (m0 = m1; m0; m0 = m1) {
m1 = m0->m_nextpkt;
m0->m_nextpkt = 0;
#ifdef __FreeBSD__
if (error == 0) {
PF_UNLOCK();
error = (*ifp->if_output)(ifp, m0, sintosa(dst),
NULL);
PF_LOCK();
} else
#else
if (error == 0)
error = (*ifp->if_output)(ifp, m0, sintosa(dst),
NULL);
else
#endif
m_freem(m0);
}
if (error == 0)
#ifdef __FreeBSD__
KMOD_IPSTAT_INC(ips_fragmented);
#else
ipstat.ips_fragmented++;
#endif
done:
if (r->rt != PF_DUPTO)
*m = NULL;
if (ro == &iproute && ro->ro_rt)
RTFREE(ro->ro_rt);
return;
bad:
m_freem(m0);
goto done;
}
#endif /* INET */
#ifdef INET6
void
pf_route6(struct mbuf **m, struct pf_rule *r, int dir, struct ifnet *oifp,
struct pf_state *s, struct pf_pdesc *pd)
{
struct mbuf *m0;
struct route_in6 ip6route;
struct route_in6 *ro;
struct sockaddr_in6 *dst;
struct ip6_hdr *ip6;
struct ifnet *ifp = NULL;
struct pf_addr naddr;
struct pf_src_node *sn = NULL;
if (m == NULL || *m == NULL || r == NULL ||
(dir != PF_IN && dir != PF_OUT) || oifp == NULL)
panic("pf_route6: invalid parameters");
#ifdef __FreeBSD__
if (pd->pf_mtag->routed++ > 3) {
#else
if ((*m)->m_pkthdr.pf.routed++ > 3) {
#endif
m0 = *m;
*m = NULL;
goto bad;
}
if (r->rt == PF_DUPTO) {
#ifdef __FreeBSD__
if ((m0 = m_dup(*m, M_DONTWAIT)) == NULL)
#else
if ((m0 = m_copym2(*m, 0, M_COPYALL, M_NOWAIT)) == NULL)
#endif
return;
} else {
if ((r->rt == PF_REPLYTO) == (r->direction == dir))
return;
m0 = *m;
}
if (m0->m_len < sizeof(struct ip6_hdr)) {
DPFPRINTF(PF_DEBUG_URGENT,
("pf_route6: m0->m_len < sizeof(struct ip6_hdr)\n"));
goto bad;
}
ip6 = mtod(m0, struct ip6_hdr *);
ro = &ip6route;
bzero((caddr_t)ro, sizeof(*ro));
dst = (struct sockaddr_in6 *)&ro->ro_dst;
dst->sin6_family = AF_INET6;
dst->sin6_len = sizeof(*dst);
dst->sin6_addr = ip6->ip6_dst;
/* Cheat. XXX why only in the v6 case??? */
if (r->rt == PF_FASTROUTE) {
#ifdef __FreeBSD__
m0->m_flags |= M_SKIP_FIREWALL;
PF_UNLOCK();
ip6_output(m0, NULL, NULL, 0, NULL, NULL, NULL);
#else
m0->m_pkthdr.pf.flags |= PF_TAG_GENERATED;
ip6_output(m0, NULL, NULL, 0, NULL, NULL, NULL);
#endif
return;
}
if (TAILQ_EMPTY(&r->rpool.list)) {
DPFPRINTF(PF_DEBUG_URGENT,
("pf_route6: TAILQ_EMPTY(&r->rpool.list)\n"));
goto bad;
}
if (s == NULL) {
pf_map_addr(AF_INET6, r, (struct pf_addr *)&ip6->ip6_src,
&naddr, NULL, &sn);
if (!PF_AZERO(&naddr, AF_INET6))
PF_ACPY((struct pf_addr *)&dst->sin6_addr,
&naddr, AF_INET6);
ifp = r->rpool.cur->kif ? r->rpool.cur->kif->pfik_ifp : NULL;
} else {
if (!PF_AZERO(&s->rt_addr, AF_INET6))
PF_ACPY((struct pf_addr *)&dst->sin6_addr,
&s->rt_addr, AF_INET6);
ifp = s->rt_kif ? s->rt_kif->pfik_ifp : NULL;
}
if (ifp == NULL)
goto bad;
if (oifp != ifp) {
#ifdef __FreeBSD__
PF_UNLOCK();
if (pf_test6(PF_OUT, ifp, &m0, NULL, NULL) != PF_PASS) {
PF_LOCK();
goto bad;
} else if (m0 == NULL) {
PF_LOCK();
goto done;
}
PF_LOCK();
#else
if (pf_test6(PF_OUT, ifp, &m0, NULL) != PF_PASS)
goto bad;
else if (m0 == NULL)
goto done;
#endif
if (m0->m_len < sizeof(struct ip6_hdr)) {
DPFPRINTF(PF_DEBUG_URGENT,
("pf_route6: m0->m_len < sizeof(struct ip6_hdr)\n"));
goto bad;
}
ip6 = mtod(m0, struct ip6_hdr *);
}
/*
* If the packet is too large for the outgoing interface,
* send back an icmp6 error.
*/
if (IN6_IS_SCOPE_EMBED(&dst->sin6_addr))
dst->sin6_addr.s6_addr16[1] = htons(ifp->if_index);
if ((u_long)m0->m_pkthdr.len <= ifp->if_mtu) {
#ifdef __FreeBSD__
PF_UNLOCK();
#endif
nd6_output(ifp, ifp, m0, dst, NULL);
#ifdef __FreeBSD__
PF_LOCK();
#endif
} else {
in6_ifstat_inc(ifp, ifs6_in_toobig);
#ifdef __FreeBSD__
if (r->rt != PF_DUPTO) {
PF_UNLOCK();
icmp6_error(m0, ICMP6_PACKET_TOO_BIG, 0, ifp->if_mtu);
PF_LOCK();
} else
#else
if (r->rt != PF_DUPTO)
icmp6_error(m0, ICMP6_PACKET_TOO_BIG, 0, ifp->if_mtu);
else
#endif
goto bad;
}
done:
if (r->rt != PF_DUPTO)
*m = NULL;
return;
bad:
m_freem(m0);
goto done;
}
#endif /* INET6 */
#ifdef __FreeBSD__
/*
* FreeBSD supports cksum offloads for the following drivers.
2004-11-08 20:24:52 +00:00
* em(4), fxp(4), ixgb(4), lge(4), ndis(4), nge(4), re(4),
* ti(4), txp(4), xl(4)
*
* CSUM_DATA_VALID | CSUM_PSEUDO_HDR :
* network driver performed cksum including pseudo header, need to verify
* csum_data
* CSUM_DATA_VALID :
* network driver performed cksum, needs to additional pseudo header
* cksum computation with partial csum_data(i.e. lack of H/W support for
* pseudo header, for instance hme(4), sk(4) and possibly gem(4))
*
* After validating the cksum of packet, set both flag CSUM_DATA_VALID and
* CSUM_PSEUDO_HDR in order to avoid recomputation of the cksum in upper
* TCP/UDP layer.
* Also, set csum_data to 0xffff to force cksum validation.
*/
int
pf_check_proto_cksum(struct mbuf *m, int off, int len, u_int8_t p, sa_family_t af)
{
u_int16_t sum = 0;
int hw_assist = 0;
struct ip *ip;
if (off < sizeof(struct ip) || len < sizeof(struct udphdr))
return (1);
if (m->m_pkthdr.len < off + len)
return (1);
switch (p) {
case IPPROTO_TCP:
if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) {
if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) {
sum = m->m_pkthdr.csum_data;
} else {
ip = mtod(m, struct ip *);
sum = in_pseudo(ip->ip_src.s_addr,
ip->ip_dst.s_addr, htonl((u_short)len +
m->m_pkthdr.csum_data + IPPROTO_TCP));
}
sum ^= 0xffff;
++hw_assist;
}
break;
case IPPROTO_UDP:
if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) {
if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) {
sum = m->m_pkthdr.csum_data;
} else {
ip = mtod(m, struct ip *);
sum = in_pseudo(ip->ip_src.s_addr,
ip->ip_dst.s_addr, htonl((u_short)len +
m->m_pkthdr.csum_data + IPPROTO_UDP));
}
sum ^= 0xffff;
++hw_assist;
}
break;
case IPPROTO_ICMP:
#ifdef INET6
case IPPROTO_ICMPV6:
#endif /* INET6 */
break;
default:
return (1);
}
if (!hw_assist) {
switch (af) {
case AF_INET:
if (p == IPPROTO_ICMP) {
if (m->m_len < off)
return (1);
m->m_data += off;
m->m_len -= off;
sum = in_cksum(m, len);
m->m_data -= off;
m->m_len += off;
} else {
if (m->m_len < sizeof(struct ip))
return (1);
sum = in4_cksum(m, p, off, len);
}
break;
#ifdef INET6
case AF_INET6:
if (m->m_len < sizeof(struct ip6_hdr))
return (1);
sum = in6_cksum(m, p, off, len);
break;
#endif /* INET6 */
default:
return (1);
}
}
if (sum) {
switch (p) {
case IPPROTO_TCP:
{
KMOD_TCPSTAT_INC(tcps_rcvbadsum);
break;
}
case IPPROTO_UDP:
{
KMOD_UDPSTAT_INC(udps_badsum);
break;
}
#ifdef INET
case IPPROTO_ICMP:
{
KMOD_ICMPSTAT_INC(icps_checksum);
break;
}
#endif
#ifdef INET6
case IPPROTO_ICMPV6:
{
KMOD_ICMP6STAT_INC(icp6s_checksum);
break;
}
#endif /* INET6 */
}
return (1);
} else {
if (p == IPPROTO_TCP || p == IPPROTO_UDP) {
m->m_pkthdr.csum_flags |=
(CSUM_DATA_VALID | CSUM_PSEUDO_HDR);
m->m_pkthdr.csum_data = 0xffff;
}
}
return (0);
}
#else /* !__FreeBSD__ */
/*
* check protocol (tcp/udp/icmp/icmp6) checksum and set mbuf flag
* off is the offset where the protocol header starts
* len is the total length of protocol header plus payload
* returns 0 when the checksum is valid, otherwise returns 1.
*/
int
pf_check_proto_cksum(struct mbuf *m, int off, int len, u_int8_t p,
sa_family_t af)
{
u_int16_t flag_ok, flag_bad;
u_int16_t sum;
switch (p) {
case IPPROTO_TCP:
flag_ok = M_TCP_CSUM_IN_OK;
flag_bad = M_TCP_CSUM_IN_BAD;
break;
case IPPROTO_UDP:
flag_ok = M_UDP_CSUM_IN_OK;
flag_bad = M_UDP_CSUM_IN_BAD;
break;
case IPPROTO_ICMP:
#ifdef INET6
case IPPROTO_ICMPV6:
#endif /* INET6 */
flag_ok = flag_bad = 0;
break;
default:
return (1);
}
if (m->m_pkthdr.csum_flags & flag_ok)
return (0);
if (m->m_pkthdr.csum_flags & flag_bad)
return (1);
if (off < sizeof(struct ip) || len < sizeof(struct udphdr))
return (1);
if (m->m_pkthdr.len < off + len)
return (1);
switch (af) {
#ifdef INET
case AF_INET:
if (p == IPPROTO_ICMP) {
if (m->m_len < off)
return (1);
m->m_data += off;
m->m_len -= off;
sum = in_cksum(m, len);
m->m_data -= off;
m->m_len += off;
} else {
if (m->m_len < sizeof(struct ip))
return (1);
sum = in4_cksum(m, p, off, len);
}
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
if (m->m_len < sizeof(struct ip6_hdr))
return (1);
sum = in6_cksum(m, p, off, len);
break;
#endif /* INET6 */
default:
return (1);
}
if (sum) {
m->m_pkthdr.csum_flags |= flag_bad;
switch (p) {
case IPPROTO_TCP:
KMOD_TCPSTAT_INC(tcps_rcvbadsum);
break;
case IPPROTO_UDP:
KMOD_UDPSTAT_INC(udps_badsum);
break;
#ifdef INET
case IPPROTO_ICMP:
KMOD_ICMPSTAT_INC(icps_checksum);
break;
#endif
#ifdef INET6
case IPPROTO_ICMPV6:
KMOD_ICMP6STAT_INC(icp6s_checksum);
break;
#endif /* INET6 */
}
return (1);
}
m->m_pkthdr.csum_flags |= flag_ok;
return (0);
}
#endif
#ifndef __FreeBSD__
struct pf_divert *
pf_find_divert(struct mbuf *m)
{
struct m_tag *mtag;
if ((mtag = m_tag_find(m, PACKET_TAG_PF_DIVERT, NULL)) == NULL)
return (NULL);
return ((struct pf_divert *)(mtag + 1));
}
struct pf_divert *
pf_get_divert(struct mbuf *m)
{
struct m_tag *mtag;
if ((mtag = m_tag_find(m, PACKET_TAG_PF_DIVERT, NULL)) == NULL) {
mtag = m_tag_get(PACKET_TAG_PF_DIVERT, sizeof(struct pf_divert),
M_NOWAIT);
if (mtag == NULL)
return (NULL);
bzero(mtag + 1, sizeof(struct pf_divert));
m_tag_prepend(m, mtag);
}
return ((struct pf_divert *)(mtag + 1));
}
#endif
#ifdef INET
int
#ifdef __FreeBSD__
pf_test(int dir, struct ifnet *ifp, struct mbuf **m0,
struct ether_header *eh, struct inpcb *inp)
#else
pf_test(int dir, struct ifnet *ifp, struct mbuf **m0,
struct ether_header *eh)
#endif
{
struct pfi_kif *kif;
u_short action, reason = 0, log = 0;
struct mbuf *m = *m0;
#ifdef __FreeBSD__
struct ip *h = NULL;
struct m_tag *ipfwtag;
struct pf_rule *a = NULL, *r = &V_pf_default_rule, *tr, *nr;
#else
struct ip *h;
struct pf_rule *a = NULL, *r = &pf_default_rule, *tr, *nr;
#endif
struct pf_state *s = NULL;
struct pf_ruleset *ruleset = NULL;
struct pf_pdesc pd;
int off, dirndx, pqid = 0;
#ifdef __FreeBSD__
PF_LOCK();
if (!V_pf_status.running)
{
PF_UNLOCK();
return (PF_PASS);
}
#else
if (!pf_status.running)
return (PF_PASS);
#endif
memset(&pd, 0, sizeof(pd));
#ifdef __FreeBSD__
if ((pd.pf_mtag = pf_get_mtag(m)) == NULL) {
PF_UNLOCK();
DPFPRINTF(PF_DEBUG_URGENT,
("pf_test: pf_get_mtag returned NULL\n"));
return (PF_DROP);
}
#endif
#ifndef __FreeBSD__
if (ifp->if_type == IFT_CARP && ifp->if_carpdev)
kif = (struct pfi_kif *)ifp->if_carpdev->if_pf_kif;
else
#endif
kif = (struct pfi_kif *)ifp->if_pf_kif;
if (kif == NULL) {
#ifdef __FreeBSD__
PF_UNLOCK();
#endif
DPFPRINTF(PF_DEBUG_URGENT,
("pf_test: kif == NULL, if_xname %s\n", ifp->if_xname));
return (PF_DROP);
}
if (kif->pfik_flags & PFI_IFLAG_SKIP)
#ifdef __FreeBSD__
{
PF_UNLOCK();
#endif
return (PF_PASS);
#ifdef __FreeBSD__
}
#endif
#ifdef __FreeBSD__
M_ASSERTPKTHDR(m);
#else
#ifdef DIAGNOSTIC
if ((m->m_flags & M_PKTHDR) == 0)
panic("non-M_PKTHDR is passed to pf_test");
#endif /* DIAGNOSTIC */
#endif
if (m->m_pkthdr.len < (int)sizeof(*h)) {
action = PF_DROP;
REASON_SET(&reason, PFRES_SHORT);
log = 1;
goto done;
}
#ifdef __FreeBSD__
if (m->m_flags & M_SKIP_FIREWALL) {
PF_UNLOCK();
return (PF_PASS);
}
#else
if (m->m_pkthdr.pf.flags & PF_TAG_GENERATED)
return (PF_PASS);
#endif
#ifdef __FreeBSD__
if (ip_divert_ptr != NULL &&
((ipfwtag = m_tag_locate(m, MTAG_IPFW_RULE, 0, NULL)) != NULL)) {
struct ipfw_rule_ref *rr = (struct ipfw_rule_ref *)(ipfwtag+1);
if (rr->info & IPFW_IS_DIVERT && rr->rulenum == 0) {
pd.pf_mtag->flags |= PF_PACKET_LOOPED;
m_tag_delete(m, ipfwtag);
}
if (pd.pf_mtag->flags & PF_FASTFWD_OURS_PRESENT) {
m->m_flags |= M_FASTFWD_OURS;
pd.pf_mtag->flags &= ~PF_FASTFWD_OURS_PRESENT;
}
} else
#endif
/* We do IP header normalization and packet reassembly here */
if (pf_normalize_ip(m0, dir, kif, &reason, &pd) != PF_PASS) {
action = PF_DROP;
goto done;
}
m = *m0; /* pf_normalize messes with m0 */
h = mtod(m, struct ip *);
off = h->ip_hl << 2;
if (off < (int)sizeof(*h)) {
action = PF_DROP;
REASON_SET(&reason, PFRES_SHORT);
log = 1;
goto done;
}
pd.src = (struct pf_addr *)&h->ip_src;
pd.dst = (struct pf_addr *)&h->ip_dst;
pd.sport = pd.dport = NULL;
pd.ip_sum = &h->ip_sum;
pd.proto_sum = NULL;
pd.proto = h->ip_p;
pd.dir = dir;
pd.sidx = (dir == PF_IN) ? 0 : 1;
pd.didx = (dir == PF_IN) ? 1 : 0;
pd.af = AF_INET;
pd.tos = h->ip_tos;
pd.tot_len = ntohs(h->ip_len);
pd.eh = eh;
/* handle fragments that didn't get reassembled by normalization */
if (h->ip_off & htons(IP_MF | IP_OFFMASK)) {
action = pf_test_fragment(&r, dir, kif, m, h,
&pd, &a, &ruleset);
goto done;
}
switch (h->ip_p) {
case IPPROTO_TCP: {
struct tcphdr th;
pd.hdr.tcp = &th;
if (!pf_pull_hdr(m, off, &th, sizeof(th),
&action, &reason, AF_INET)) {
log = action != PF_PASS;
goto done;
}
pd.p_len = pd.tot_len - off - (th.th_off << 2);
if ((th.th_flags & TH_ACK) && pd.p_len == 0)
pqid = 1;
action = pf_normalize_tcp(dir, kif, m, 0, off, h, &pd);
if (action == PF_DROP)
goto done;
action = pf_test_state_tcp(&s, dir, kif, m, off, h, &pd,
&reason);
if (action == PF_PASS) {
#if NPFSYNC > 0
#ifdef __FreeBSD__
if (pfsync_update_state_ptr != NULL)
pfsync_update_state_ptr(s);
#else
pfsync_update_state(s);
#endif
#endif /* NPFSYNC */
r = s->rule.ptr;
a = s->anchor.ptr;
log = s->log;
} else if (s == NULL)
#ifdef __FreeBSD__
action = pf_test_rule(&r, &s, dir, kif,
m, off, h, &pd, &a, &ruleset, NULL, inp);
#else
action = pf_test_rule(&r, &s, dir, kif,
m, off, h, &pd, &a, &ruleset, &ipintrq);
#endif
break;
}
case IPPROTO_UDP: {
struct udphdr uh;
pd.hdr.udp = &uh;
if (!pf_pull_hdr(m, off, &uh, sizeof(uh),
&action, &reason, AF_INET)) {
log = action != PF_PASS;
goto done;
}
if (uh.uh_dport == 0 ||
ntohs(uh.uh_ulen) > m->m_pkthdr.len - off ||
ntohs(uh.uh_ulen) < sizeof(struct udphdr)) {
action = PF_DROP;
REASON_SET(&reason, PFRES_SHORT);
goto done;
}
action = pf_test_state_udp(&s, dir, kif, m, off, h, &pd);
if (action == PF_PASS) {
#if NPFSYNC > 0
#ifdef __FreeBSD__
if (pfsync_update_state_ptr != NULL)
pfsync_update_state_ptr(s);
#else
pfsync_update_state(s);
#endif
#endif /* NPFSYNC */
r = s->rule.ptr;
a = s->anchor.ptr;
log = s->log;
} else if (s == NULL)
#ifdef __FreeBSD__
action = pf_test_rule(&r, &s, dir, kif,
m, off, h, &pd, &a, &ruleset, NULL, inp);
#else
action = pf_test_rule(&r, &s, dir, kif,
m, off, h, &pd, &a, &ruleset, &ipintrq);
#endif
break;
}
case IPPROTO_ICMP: {
struct icmp ih;
pd.hdr.icmp = &ih;
if (!pf_pull_hdr(m, off, &ih, ICMP_MINLEN,
&action, &reason, AF_INET)) {
log = action != PF_PASS;
goto done;
}
action = pf_test_state_icmp(&s, dir, kif, m, off, h, &pd,
&reason);
if (action == PF_PASS) {
#if NPFSYNC > 0
#ifdef __FreeBSD__
if (pfsync_update_state_ptr != NULL)
pfsync_update_state_ptr(s);
#else
pfsync_update_state(s);
#endif
#endif /* NPFSYNC */
r = s->rule.ptr;
a = s->anchor.ptr;
log = s->log;
} else if (s == NULL)
#ifdef __FreeBSD__
action = pf_test_rule(&r, &s, dir, kif,
m, off, h, &pd, &a, &ruleset, NULL, inp);
#else
action = pf_test_rule(&r, &s, dir, kif,
m, off, h, &pd, &a, &ruleset, &ipintrq);
#endif
break;
}
#ifdef INET6
case IPPROTO_ICMPV6: {
action = PF_DROP;
DPFPRINTF(PF_DEBUG_MISC,
("pf: dropping IPv4 packet with ICMPv6 payload\n"));
goto done;
}
#endif
default:
action = pf_test_state_other(&s, dir, kif, m, &pd);
if (action == PF_PASS) {
#if NPFSYNC > 0
#ifdef __FreeBSD__
if (pfsync_update_state_ptr != NULL)
pfsync_update_state_ptr(s);
#else
pfsync_update_state(s);
#endif
#endif /* NPFSYNC */
r = s->rule.ptr;
a = s->anchor.ptr;
log = s->log;
} else if (s == NULL)
#ifdef __FreeBSD__
action = pf_test_rule(&r, &s, dir, kif, m, off, h,
&pd, &a, &ruleset, NULL, inp);
#else
action = pf_test_rule(&r, &s, dir, kif, m, off, h,
&pd, &a, &ruleset, &ipintrq);
#endif
break;
}
done:
if (action == PF_PASS && h->ip_hl > 5 &&
!((s && s->state_flags & PFSTATE_ALLOWOPTS) || r->allow_opts)) {
action = PF_DROP;
REASON_SET(&reason, PFRES_IPOPTIONS);
log = 1;
DPFPRINTF(PF_DEBUG_MISC,
("pf: dropping packet with ip options\n"));
}
if ((s && s->tag) || r->rtableid)
#ifdef __FreeBSD__
pf_tag_packet(m, s ? s->tag : 0, r->rtableid, pd.pf_mtag);
#else
pf_tag_packet(m, s ? s->tag : 0, r->rtableid);
#endif
if (dir == PF_IN && s && s->key[PF_SK_STACK])
#ifdef __FreeBSD__
pd.pf_mtag->statekey = s->key[PF_SK_STACK];
#else
m->m_pkthdr.pf.statekey = s->key[PF_SK_STACK];
#endif
#ifdef ALTQ
if (action == PF_PASS && r->qid) {
#ifdef __FreeBSD__
if (pqid || (pd.tos & IPTOS_LOWDELAY))
pd.pf_mtag->qid = r->pqid;
else
pd.pf_mtag->qid = r->qid;
/* add hints for ecn */
pd.pf_mtag->hdr = h;
#else
if (pqid || (pd.tos & IPTOS_LOWDELAY))
m->m_pkthdr.pf.qid = r->pqid;
else
m->m_pkthdr.pf.qid = r->qid;
/* add hints for ecn */
m->m_pkthdr.pf.hdr = h;
#endif
}
#endif /* ALTQ */
/*
* connections redirected to loopback should not match sockets
* bound specifically to loopback due to security implications,
* see tcp_input() and in_pcblookup_listen().
*/
if (dir == PF_IN && action == PF_PASS && (pd.proto == IPPROTO_TCP ||
pd.proto == IPPROTO_UDP) && s != NULL && s->nat_rule.ptr != NULL &&
(s->nat_rule.ptr->action == PF_RDR ||
s->nat_rule.ptr->action == PF_BINAT) &&
(ntohl(pd.dst->v4.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET)
#ifdef __FreeBSD__
m->m_flags |= M_SKIP_FIREWALL;
#else
m->m_pkthdr.pf.flags |= PF_TAG_TRANSLATE_LOCALHOST;
#endif
#ifdef __FreeBSD__
if (action == PF_PASS && r->divert.port &&
ip_divert_ptr != NULL && !PACKET_LOOPED()) {
ipfwtag = m_tag_alloc(MTAG_IPFW_RULE, 0,
sizeof(struct ipfw_rule_ref), M_NOWAIT | M_ZERO);
if (ipfwtag != NULL) {
((struct ipfw_rule_ref *)(ipfwtag+1))->info = r->divert.port;
((struct ipfw_rule_ref *)(ipfwtag+1))->rulenum = dir;
m_tag_prepend(m, ipfwtag);
PF_UNLOCK();
if (m->m_flags & M_FASTFWD_OURS) {
pd.pf_mtag->flags |= PF_FASTFWD_OURS_PRESENT;
m->m_flags &= ~M_FASTFWD_OURS;
}
ip_divert_ptr(*m0,
dir == PF_IN ? DIR_IN : DIR_OUT);
*m0 = NULL;
return (action);
} else {
/* XXX: ipfw has the same behaviour! */
action = PF_DROP;
REASON_SET(&reason, PFRES_MEMORY);
log = 1;
DPFPRINTF(PF_DEBUG_MISC,
("pf: failed to allocate divert tag\n"));
}
}
#else
if (dir == PF_IN && action == PF_PASS && r->divert.port) {
struct pf_divert *divert;
if ((divert = pf_get_divert(m))) {
m->m_pkthdr.pf.flags |= PF_TAG_DIVERTED;
divert->port = r->divert.port;
divert->addr.ipv4 = r->divert.addr.v4;
}
}
#endif
if (log) {
struct pf_rule *lr;
if (s != NULL && s->nat_rule.ptr != NULL &&
s->nat_rule.ptr->log & PF_LOG_ALL)
lr = s->nat_rule.ptr;
else
lr = r;
PFLOG_PACKET(kif, h, m, AF_INET, dir, reason, lr, a, ruleset,
&pd);
}
kif->pfik_bytes[0][dir == PF_OUT][action != PF_PASS] += pd.tot_len;
kif->pfik_packets[0][dir == PF_OUT][action != PF_PASS]++;
if (action == PF_PASS || r->action == PF_DROP) {
dirndx = (dir == PF_OUT);
r->packets[dirndx]++;
r->bytes[dirndx] += pd.tot_len;
if (a != NULL) {
a->packets[dirndx]++;
a->bytes[dirndx] += pd.tot_len;
}
if (s != NULL) {
if (s->nat_rule.ptr != NULL) {
s->nat_rule.ptr->packets[dirndx]++;
s->nat_rule.ptr->bytes[dirndx] += pd.tot_len;
}
if (s->src_node != NULL) {
s->src_node->packets[dirndx]++;
s->src_node->bytes[dirndx] += pd.tot_len;
}
if (s->nat_src_node != NULL) {
s->nat_src_node->packets[dirndx]++;
s->nat_src_node->bytes[dirndx] += pd.tot_len;
}
dirndx = (dir == s->direction) ? 0 : 1;
s->packets[dirndx]++;
s->bytes[dirndx] += pd.tot_len;
}
tr = r;
nr = (s != NULL) ? s->nat_rule.ptr : pd.nat_rule;
#ifdef __FreeBSD__
if (nr != NULL && r == &V_pf_default_rule)
#else
if (nr != NULL && r == &pf_default_rule)
#endif
tr = nr;
if (tr->src.addr.type == PF_ADDR_TABLE)
pfr_update_stats(tr->src.addr.p.tbl,
(s == NULL) ? pd.src :
&s->key[(s->direction == PF_IN)]->
addr[(s->direction == PF_OUT)],
pd.af, pd.tot_len, dir == PF_OUT,
r->action == PF_PASS, tr->src.neg);
if (tr->dst.addr.type == PF_ADDR_TABLE)
pfr_update_stats(tr->dst.addr.p.tbl,
(s == NULL) ? pd.dst :
&s->key[(s->direction == PF_IN)]->
addr[(s->direction == PF_IN)],
pd.af, pd.tot_len, dir == PF_OUT,
r->action == PF_PASS, tr->dst.neg);
}
switch (action) {
case PF_SYNPROXY_DROP:
m_freem(*m0);
case PF_DEFER:
*m0 = NULL;
action = PF_PASS;
break;
default:
/* pf_route can free the mbuf causing *m0 to become NULL */
if (r->rt)
pf_route(m0, r, dir, kif->pfik_ifp, s, &pd);
break;
}
#ifdef __FreeBSD__
PF_UNLOCK();
#endif
return (action);
}
#endif /* INET */
#ifdef INET6
int
#ifdef __FreeBSD__
pf_test6(int dir, struct ifnet *ifp, struct mbuf **m0,
struct ether_header *eh, struct inpcb *inp)
#else
pf_test6(int dir, struct ifnet *ifp, struct mbuf **m0,
struct ether_header *eh)
#endif
{
struct pfi_kif *kif;
u_short action, reason = 0, log = 0;
struct mbuf *m = *m0, *n = NULL;
#ifdef __FreeBSD__
struct ip6_hdr *h = NULL;
struct pf_rule *a = NULL, *r = &V_pf_default_rule, *tr, *nr;
#else
struct ip6_hdr *h;
struct pf_rule *a = NULL, *r = &pf_default_rule, *tr, *nr;
#endif
struct pf_state *s = NULL;
struct pf_ruleset *ruleset = NULL;
struct pf_pdesc pd;
int off, terminal = 0, dirndx, rh_cnt = 0;
#ifdef __FreeBSD__
PF_LOCK();
if (!V_pf_status.running) {
PF_UNLOCK();
return (PF_PASS);
}
#else
if (!pf_status.running)
return (PF_PASS);
#endif
memset(&pd, 0, sizeof(pd));
#ifdef __FreeBSD__
if ((pd.pf_mtag = pf_get_mtag(m)) == NULL) {
PF_UNLOCK();
DPFPRINTF(PF_DEBUG_URGENT,
("pf_test: pf_get_mtag returned NULL\n"));
return (PF_DROP);
}
#endif
#ifndef __FreeBSD__
if (ifp->if_type == IFT_CARP && ifp->if_carpdev)
kif = (struct pfi_kif *)ifp->if_carpdev->if_pf_kif;
else
#endif
kif = (struct pfi_kif *)ifp->if_pf_kif;
if (kif == NULL) {
#ifdef __FreeBSD__
PF_UNLOCK();
#endif
DPFPRINTF(PF_DEBUG_URGENT,
("pf_test6: kif == NULL, if_xname %s\n", ifp->if_xname));
return (PF_DROP);
}
if (kif->pfik_flags & PFI_IFLAG_SKIP)
#ifdef __FreeBSD__
{
PF_UNLOCK();
#endif
return (PF_PASS);
#ifdef __FreeBSD__
}
#endif
#ifdef __FreeBSD__
M_ASSERTPKTHDR(m);
#else
#ifdef DIAGNOSTIC
if ((m->m_flags & M_PKTHDR) == 0)
panic("non-M_PKTHDR is passed to pf_test6");
#endif /* DIAGNOSTIC */
#endif
if (m->m_pkthdr.len < (int)sizeof(*h)) {
action = PF_DROP;
REASON_SET(&reason, PFRES_SHORT);
log = 1;
goto done;
}
#ifdef __FreeBSD__
if (pd.pf_mtag->flags & PF_TAG_GENERATED)
#else
if (m->m_pkthdr.pf.flags & PF_TAG_GENERATED)
#endif
return (PF_PASS);
/* We do IP header normalization and packet reassembly here */
if (pf_normalize_ip6(m0, dir, kif, &reason, &pd) != PF_PASS) {
action = PF_DROP;
goto done;
}
m = *m0; /* pf_normalize messes with m0 */
h = mtod(m, struct ip6_hdr *);
#if 1
/*
* we do not support jumbogram yet. if we keep going, zero ip6_plen
* will do something bad, so drop the packet for now.
*/
if (htons(h->ip6_plen) == 0) {
action = PF_DROP;
REASON_SET(&reason, PFRES_NORM); /*XXX*/
goto done;
}
#endif
pd.src = (struct pf_addr *)&h->ip6_src;
pd.dst = (struct pf_addr *)&h->ip6_dst;
pd.sport = pd.dport = NULL;
pd.ip_sum = NULL;
pd.proto_sum = NULL;
pd.dir = dir;
pd.sidx = (dir == PF_IN) ? 0 : 1;
pd.didx = (dir == PF_IN) ? 1 : 0;
pd.af = AF_INET6;
pd.tos = 0;
pd.tot_len = ntohs(h->ip6_plen) + sizeof(struct ip6_hdr);
pd.eh = eh;
off = ((caddr_t)h - m->m_data) + sizeof(struct ip6_hdr);
pd.proto = h->ip6_nxt;
do {
switch (pd.proto) {
case IPPROTO_FRAGMENT:
action = pf_test_fragment(&r, dir, kif, m, h,
&pd, &a, &ruleset);
if (action == PF_DROP)
REASON_SET(&reason, PFRES_FRAG);
goto done;
case IPPROTO_ROUTING: {
struct ip6_rthdr rthdr;
if (rh_cnt++) {
DPFPRINTF(PF_DEBUG_MISC,
("pf: IPv6 more than one rthdr\n"));
action = PF_DROP;
REASON_SET(&reason, PFRES_IPOPTIONS);
log = 1;
goto done;
}
if (!pf_pull_hdr(m, off, &rthdr, sizeof(rthdr), NULL,
&reason, pd.af)) {
DPFPRINTF(PF_DEBUG_MISC,
("pf: IPv6 short rthdr\n"));
action = PF_DROP;
REASON_SET(&reason, PFRES_SHORT);
log = 1;
goto done;
}
if (rthdr.ip6r_type == IPV6_RTHDR_TYPE_0) {
DPFPRINTF(PF_DEBUG_MISC,
("pf: IPv6 rthdr0\n"));
action = PF_DROP;
REASON_SET(&reason, PFRES_IPOPTIONS);
log = 1;
goto done;
}
/* FALLTHROUGH */
}
case IPPROTO_AH:
case IPPROTO_HOPOPTS:
case IPPROTO_DSTOPTS: {
/* get next header and header length */
struct ip6_ext opt6;
if (!pf_pull_hdr(m, off, &opt6, sizeof(opt6),
NULL, &reason, pd.af)) {
DPFPRINTF(PF_DEBUG_MISC,
("pf: IPv6 short opt\n"));
action = PF_DROP;
log = 1;
goto done;
}
if (pd.proto == IPPROTO_AH)
off += (opt6.ip6e_len + 2) * 4;
else
off += (opt6.ip6e_len + 1) * 8;
pd.proto = opt6.ip6e_nxt;
/* goto the next header */
break;
}
default:
terminal++;
break;
}
} while (!terminal);
/* if there's no routing header, use unmodified mbuf for checksumming */
if (!n)
n = m;
switch (pd.proto) {
case IPPROTO_TCP: {
struct tcphdr th;
pd.hdr.tcp = &th;
if (!pf_pull_hdr(m, off, &th, sizeof(th),
&action, &reason, AF_INET6)) {
log = action != PF_PASS;
goto done;
}
pd.p_len = pd.tot_len - off - (th.th_off << 2);
action = pf_normalize_tcp(dir, kif, m, 0, off, h, &pd);
if (action == PF_DROP)
goto done;
action = pf_test_state_tcp(&s, dir, kif, m, off, h, &pd,
&reason);
if (action == PF_PASS) {
#if NPFSYNC > 0
#ifdef __FreeBSD__
if (pfsync_update_state_ptr != NULL)
pfsync_update_state_ptr(s);
#else
pfsync_update_state(s);
#endif
#endif /* NPFSYNC */
r = s->rule.ptr;
a = s->anchor.ptr;
log = s->log;
} else if (s == NULL)
#ifdef __FreeBSD__
action = pf_test_rule(&r, &s, dir, kif,
m, off, h, &pd, &a, &ruleset, NULL, inp);
#else
action = pf_test_rule(&r, &s, dir, kif,
m, off, h, &pd, &a, &ruleset, &ip6intrq);
#endif
break;
}
case IPPROTO_UDP: {
struct udphdr uh;
pd.hdr.udp = &uh;
if (!pf_pull_hdr(m, off, &uh, sizeof(uh),
&action, &reason, AF_INET6)) {
log = action != PF_PASS;
goto done;
}
if (uh.uh_dport == 0 ||
ntohs(uh.uh_ulen) > m->m_pkthdr.len - off ||
ntohs(uh.uh_ulen) < sizeof(struct udphdr)) {
action = PF_DROP;
REASON_SET(&reason, PFRES_SHORT);
goto done;
}
action = pf_test_state_udp(&s, dir, kif, m, off, h, &pd);
if (action == PF_PASS) {
#if NPFSYNC > 0
#ifdef __FreeBSD__
if (pfsync_update_state_ptr != NULL)
pfsync_update_state_ptr(s);
#else
pfsync_update_state(s);
#endif
#endif /* NPFSYNC */
r = s->rule.ptr;
a = s->anchor.ptr;
log = s->log;
} else if (s == NULL)
#ifdef __FreeBSD__
action = pf_test_rule(&r, &s, dir, kif,
m, off, h, &pd, &a, &ruleset, NULL, inp);
#else
action = pf_test_rule(&r, &s, dir, kif,
m, off, h, &pd, &a, &ruleset, &ip6intrq);
#endif
break;
}
case IPPROTO_ICMP: {
action = PF_DROP;
DPFPRINTF(PF_DEBUG_MISC,
("pf: dropping IPv6 packet with ICMPv4 payload\n"));
goto done;
}
case IPPROTO_ICMPV6: {
struct icmp6_hdr ih;
pd.hdr.icmp6 = &ih;
if (!pf_pull_hdr(m, off, &ih, sizeof(ih),
&action, &reason, AF_INET6)) {
log = action != PF_PASS;
goto done;
}
action = pf_test_state_icmp(&s, dir, kif,
m, off, h, &pd, &reason);
if (action == PF_PASS) {
#if NPFSYNC > 0
#ifdef __FreeBSD__
if (pfsync_update_state_ptr != NULL)
pfsync_update_state_ptr(s);
#else
pfsync_update_state(s);
#endif
#endif /* NPFSYNC */
r = s->rule.ptr;
a = s->anchor.ptr;
log = s->log;
} else if (s == NULL)
#ifdef __FreeBSD__
action = pf_test_rule(&r, &s, dir, kif,
m, off, h, &pd, &a, &ruleset, NULL, inp);
#else
action = pf_test_rule(&r, &s, dir, kif,
m, off, h, &pd, &a, &ruleset, &ip6intrq);
#endif
break;
}
default:
action = pf_test_state_other(&s, dir, kif, m, &pd);
if (action == PF_PASS) {
#if NPFSYNC > 0
#ifdef __FreeBSD__
if (pfsync_update_state_ptr != NULL)
pfsync_update_state_ptr(s);
#else
pfsync_update_state(s);
#endif
#endif /* NPFSYNC */
r = s->rule.ptr;
a = s->anchor.ptr;
log = s->log;
} else if (s == NULL)
#ifdef __FreeBSD__
action = pf_test_rule(&r, &s, dir, kif, m, off, h,
&pd, &a, &ruleset, NULL, inp);
#else
action = pf_test_rule(&r, &s, dir, kif, m, off, h,
&pd, &a, &ruleset, &ip6intrq);
#endif
break;
}
done:
if (n != m) {
m_freem(n);
n = NULL;
}
/* handle dangerous IPv6 extension headers. */
if (action == PF_PASS && rh_cnt &&
!((s && s->state_flags & PFSTATE_ALLOWOPTS) || r->allow_opts)) {
action = PF_DROP;
REASON_SET(&reason, PFRES_IPOPTIONS);
log = 1;
DPFPRINTF(PF_DEBUG_MISC,
("pf: dropping packet with dangerous v6 headers\n"));
}
if ((s && s->tag) || r->rtableid)
#ifdef __FreeBSD__
pf_tag_packet(m, s ? s->tag : 0, r->rtableid, pd.pf_mtag);
#else
pf_tag_packet(m, s ? s->tag : 0, r->rtableid);
#endif
if (dir == PF_IN && s && s->key[PF_SK_STACK])
#ifdef __FreeBSD__
pd.pf_mtag->statekey = s->key[PF_SK_STACK];
#else
m->m_pkthdr.pf.statekey = s->key[PF_SK_STACK];
#endif
#ifdef ALTQ
if (action == PF_PASS && r->qid) {
#ifdef __FreeBSD__
if (pd.tos & IPTOS_LOWDELAY)
pd.pf_mtag->qid = r->pqid;
else
pd.pf_mtag->qid = r->qid;
/* add hints for ecn */
pd.pf_mtag->hdr = h;
#else
if (pd.tos & IPTOS_LOWDELAY)
m->m_pkthdr.pf.qid = r->pqid;
else
m->m_pkthdr.pf.qid = r->qid;
/* add hints for ecn */
m->m_pkthdr.pf.hdr = h;
#endif
}
#endif /* ALTQ */
if (dir == PF_IN && action == PF_PASS && (pd.proto == IPPROTO_TCP ||
pd.proto == IPPROTO_UDP) && s != NULL && s->nat_rule.ptr != NULL &&
(s->nat_rule.ptr->action == PF_RDR ||
s->nat_rule.ptr->action == PF_BINAT) &&
IN6_IS_ADDR_LOOPBACK(&pd.dst->v6))
#ifdef __FreeBSD__
m->m_flags |= M_SKIP_FIREWALL;
#else
m->m_pkthdr.pf.flags |= PF_TAG_TRANSLATE_LOCALHOST;
#endif
#ifdef __FreeBSD__
/* XXX: Anybody working on it?! */
if (r->divert.port)
printf("pf: divert(9) is not supported for IPv6\n");
#else
if (dir == PF_IN && action == PF_PASS && r->divert.port) {
struct pf_divert *divert;
if ((divert = pf_get_divert(m))) {
m->m_pkthdr.pf.flags |= PF_TAG_DIVERTED;
divert->port = r->divert.port;
divert->addr.ipv6 = r->divert.addr.v6;
}
}
#endif
if (log) {
struct pf_rule *lr;
if (s != NULL && s->nat_rule.ptr != NULL &&
s->nat_rule.ptr->log & PF_LOG_ALL)
lr = s->nat_rule.ptr;
else
lr = r;
PFLOG_PACKET(kif, h, m, AF_INET6, dir, reason, lr, a, ruleset,
&pd);
}
kif->pfik_bytes[1][dir == PF_OUT][action != PF_PASS] += pd.tot_len;
kif->pfik_packets[1][dir == PF_OUT][action != PF_PASS]++;
if (action == PF_PASS || r->action == PF_DROP) {
dirndx = (dir == PF_OUT);
r->packets[dirndx]++;
r->bytes[dirndx] += pd.tot_len;
if (a != NULL) {
a->packets[dirndx]++;
a->bytes[dirndx] += pd.tot_len;
}
if (s != NULL) {
if (s->nat_rule.ptr != NULL) {
s->nat_rule.ptr->packets[dirndx]++;
s->nat_rule.ptr->bytes[dirndx] += pd.tot_len;
}
if (s->src_node != NULL) {
s->src_node->packets[dirndx]++;
s->src_node->bytes[dirndx] += pd.tot_len;
}
if (s->nat_src_node != NULL) {
s->nat_src_node->packets[dirndx]++;
s->nat_src_node->bytes[dirndx] += pd.tot_len;
}
dirndx = (dir == s->direction) ? 0 : 1;
s->packets[dirndx]++;
s->bytes[dirndx] += pd.tot_len;
}
tr = r;
nr = (s != NULL) ? s->nat_rule.ptr : pd.nat_rule;
#ifdef __FreeBSD__
if (nr != NULL && r == &V_pf_default_rule)
#else
if (nr != NULL && r == &pf_default_rule)
#endif
tr = nr;
if (tr->src.addr.type == PF_ADDR_TABLE)
pfr_update_stats(tr->src.addr.p.tbl,
(s == NULL) ? pd.src :
&s->key[(s->direction == PF_IN)]->addr[0],
pd.af, pd.tot_len, dir == PF_OUT,
r->action == PF_PASS, tr->src.neg);
if (tr->dst.addr.type == PF_ADDR_TABLE)
pfr_update_stats(tr->dst.addr.p.tbl,
(s == NULL) ? pd.dst :
&s->key[(s->direction == PF_IN)]->addr[1],
pd.af, pd.tot_len, dir == PF_OUT,
r->action == PF_PASS, tr->dst.neg);
}
switch (action) {
case PF_SYNPROXY_DROP:
m_freem(*m0);
case PF_DEFER:
*m0 = NULL;
action = PF_PASS;
break;
default:
/* pf_route6 can free the mbuf causing *m0 to become NULL */
if (r->rt)
pf_route6(m0, r, dir, kif->pfik_ifp, s, &pd);
break;
}
#ifdef __FreeBSD__
PF_UNLOCK();
#endif
return (action);
}
#endif /* INET6 */
int
pf_check_congestion(struct ifqueue *ifq)
{
#ifdef __FreeBSD__
/* XXX_IMPORT: later */
return (0);
#else
if (ifq->ifq_congestion)
return (1);
else
return (0);
#endif
}
/*
* must be called whenever any addressing information such as
* address, port, protocol has changed
*/
void
pf_pkt_addr_changed(struct mbuf *m)
{
#ifdef __FreeBSD__
struct pf_mtag *pf_tag;
if ((pf_tag = pf_find_mtag(m)) != NULL)
pf_tag->statekey = NULL;
#else
m->m_pkthdr.pf.statekey = NULL;
#endif
}