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freebsd-nq/sys/netpfil/pf/pf.c

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/*-
* Copyright (c) 2001 Daniel Hartmeier
* Copyright (c) 2002 - 2008 Henning Brauer
* Copyright (c) 2012 Gleb Smirnoff <glebius@FreeBSD.org>
* 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.
*
* $OpenBSD: pf.c,v 1.634 2009/02/27 12:37:45 henning Exp $
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_bpf.h"
#include "opt_pf.h"
#include <sys/param.h>
#include <sys/bus.h>
#include <sys/endian.h>
#include <sys/hash.h>
#include <sys/interrupt.h>
#include <sys/kernel.h>
#include <sys/kthread.h>
#include <sys/limits.h>
#include <sys/mbuf.h>
#include <sys/md5.h>
#include <sys/random.h>
#include <sys/refcount.h>
#include <sys/socket.h>
#include <sys/sysctl.h>
#include <sys/taskqueue.h>
#include <sys/ucred.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/if_types.h>
#include <net/route.h>
#include <net/radix_mpath.h>
#include <net/vnet.h>
#include <net/pfvar.h>
#include <net/if_pflog.h>
#include <net/if_pfsync.h>
#include <netinet/in_pcb.h>
#include <netinet/in_var.h>
#include <netinet/ip.h>
#include <netinet/ip_fw.h>
#include <netinet/ip_icmp.h>
#include <netinet/icmp_var.h>
#include <netinet/ip_var.h>
#include <netinet/tcp.h>
#include <netinet/tcp_fsm.h>
#include <netinet/tcp_seq.h>
#include <netinet/tcp_timer.h>
#include <netinet/tcp_var.h>
#include <netinet/udp.h>
#include <netinet/udp_var.h>
#include <netpfil/ipfw/ip_fw_private.h> /* XXX: only for DIR_IN/DIR_OUT */
#ifdef INET6
#include <netinet/ip6.h>
#include <netinet/icmp6.h>
#include <netinet6/nd6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/in6_pcb.h>
#endif /* INET6 */
#include <machine/in_cksum.h>
#include <security/mac/mac_framework.h>
#define DPFPRINTF(n, x) if (V_pf_status.debug >= (n)) printf x
/*
* Global variables
*/
/* state tables */
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)
/*
* Queue for pf_intr() sends.
*/
static MALLOC_DEFINE(M_PFTEMP, "pf_temp", "pf(4) temporary allocations");
struct pf_send_entry {
STAILQ_ENTRY(pf_send_entry) pfse_next;
struct mbuf *pfse_m;
enum {
PFSE_IP,
PFSE_IP6,
PFSE_ICMP,
PFSE_ICMP6,
} pfse_type;
union {
struct route ro;
struct {
int type;
int code;
int mtu;
} icmpopts;
} u;
#define pfse_ro u.ro
#define pfse_icmp_type u.icmpopts.type
#define pfse_icmp_code u.icmpopts.code
#define pfse_icmp_mtu u.icmpopts.mtu
};
STAILQ_HEAD(pf_send_head, pf_send_entry);
static VNET_DEFINE(struct pf_send_head, pf_sendqueue);
#define V_pf_sendqueue VNET(pf_sendqueue)
static struct mtx pf_sendqueue_mtx;
#define PF_SENDQ_LOCK() mtx_lock(&pf_sendqueue_mtx)
#define PF_SENDQ_UNLOCK() mtx_unlock(&pf_sendqueue_mtx)
/*
* Queue for pf_overload_task() tasks.
*/
struct pf_overload_entry {
SLIST_ENTRY(pf_overload_entry) next;
struct pf_addr addr;
sa_family_t af;
uint8_t dir;
struct pf_rule *rule;
};
SLIST_HEAD(pf_overload_head, pf_overload_entry);
static VNET_DEFINE(struct pf_overload_head, pf_overloadqueue);
#define V_pf_overloadqueue VNET(pf_overloadqueue)
static VNET_DEFINE(struct task, pf_overloadtask);
#define V_pf_overloadtask VNET(pf_overloadtask)
static struct mtx pf_overloadqueue_mtx;
#define PF_OVERLOADQ_LOCK() mtx_lock(&pf_overloadqueue_mtx)
#define PF_OVERLOADQ_UNLOCK() mtx_unlock(&pf_overloadqueue_mtx)
VNET_DEFINE(struct pf_rulequeue, pf_unlinked_rules);
struct mtx pf_unlnkdrules_mtx;
static VNET_DEFINE(uma_zone_t, pf_sources_z);
#define V_pf_sources_z VNET(pf_sources_z)
uma_zone_t pf_mtag_z;
VNET_DEFINE(uma_zone_t, pf_state_z);
VNET_DEFINE(uma_zone_t, pf_state_key_z);
VNET_DEFINE(uint64_t, pf_stateid[MAXCPU]);
#define PFID_CPUBITS 8
#define PFID_CPUSHIFT (sizeof(uint64_t) * NBBY - PFID_CPUBITS)
#define PFID_CPUMASK ((uint64_t)((1 << PFID_CPUBITS) - 1) << PFID_CPUSHIFT)
#define PFID_MAXID (~PFID_CPUMASK)
CTASSERT((1 << PFID_CPUBITS) >= MAXCPU);
static void pf_src_tree_remove_state(struct pf_state *);
static void pf_init_threshold(struct pf_threshold *, u_int32_t,
u_int32_t);
static void pf_add_threshold(struct pf_threshold *);
static int pf_check_threshold(struct pf_threshold *);
static 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);
static int pf_modulate_sack(struct mbuf *, int, struct pf_pdesc *,
struct tcphdr *, struct pf_state_peer *);
static 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);
static void pf_send_tcp(struct mbuf *,
const struct pf_rule *, sa_family_t,
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 ifnet *);
static void pf_send_icmp(struct mbuf *, u_int8_t, u_int8_t,
sa_family_t, struct pf_rule *);
static void pf_detach_state(struct pf_state *);
static int pf_state_key_attach(struct pf_state_key *,
struct pf_state_key *, struct pf_state *);
static void pf_state_key_detach(struct pf_state *, int);
static int pf_state_key_ctor(void *, int, void *, int);
static u_int32_t pf_tcp_iss(struct pf_pdesc *);
static int pf_test_rule(struct pf_rule **, struct pf_state **,
int, struct pfi_kif *, struct mbuf *, int,
struct pf_pdesc *, struct pf_rule **,
struct pf_ruleset **, struct inpcb *);
static 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 mbuf *, int,
u_int16_t, u_int16_t, int *, struct pfi_kif *,
struct pf_state **, int, u_int16_t, u_int16_t,
int);
static int pf_test_fragment(struct pf_rule **, int,
struct pfi_kif *, struct mbuf *, void *,
struct pf_pdesc *, struct pf_rule **,
struct pf_ruleset **);
static 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 *);
static int pf_tcp_track_sloppy(struct pf_state_peer *,
struct pf_state_peer *, struct pf_state **,
struct pf_pdesc *, u_short *);
static int pf_test_state_tcp(struct pf_state **, int,
struct pfi_kif *, struct mbuf *, int,
void *, struct pf_pdesc *, u_short *);
static int pf_test_state_udp(struct pf_state **, int,
struct pfi_kif *, struct mbuf *, int,
void *, struct pf_pdesc *);
static int pf_test_state_icmp(struct pf_state **, int,
struct pfi_kif *, struct mbuf *, int,
void *, struct pf_pdesc *, u_short *);
static int pf_test_state_other(struct pf_state **, int,
struct pfi_kif *, struct mbuf *, struct pf_pdesc *);
static u_int8_t pf_get_wscale(struct mbuf *, int, u_int16_t,
sa_family_t);
static u_int16_t pf_get_mss(struct mbuf *, int, u_int16_t,
sa_family_t);
static u_int16_t pf_calc_mss(struct pf_addr *, sa_family_t,
int, u_int16_t);
static void pf_set_rt_ifp(struct pf_state *,
struct pf_addr *);
static int pf_check_proto_cksum(struct mbuf *, int, int,
u_int8_t, sa_family_t);
static void pf_print_state_parts(struct pf_state *,
struct pf_state_key *, struct pf_state_key *);
static int pf_addr_wrap_neq(struct pf_addr_wrap *,
struct pf_addr_wrap *);
static struct pf_state *pf_find_state(struct pfi_kif *,
struct pf_state_key_cmp *, u_int);
static int pf_src_connlimit(struct pf_state **);
static void pf_overload_task(void *v, int pending);
static int pf_insert_src_node(struct pf_src_node **,
struct pf_rule *, struct pf_addr *, sa_family_t);
static u_int pf_purge_expired_states(u_int, int);
static void pf_purge_unlinked_rules(void);
static int pf_mtag_uminit(void *, int, int);
static void pf_mtag_free(struct m_tag *);
#ifdef INET
static void pf_route(struct mbuf **, struct pf_rule *, int,
struct ifnet *, struct pf_state *,
struct pf_pdesc *);
#endif /* INET */
#ifdef INET6
static void pf_change_a6(struct pf_addr *, u_int16_t *,
struct pf_addr *, u_int8_t);
static void pf_route6(struct mbuf **, struct pf_rule *, int,
struct ifnet *, struct pf_state *,
struct pf_pdesc *);
#endif /* INET6 */
int in4_cksum(struct mbuf *m, u_int8_t nxt, int off, int len);
VNET_DECLARE(int, pf_end_threads);
VNET_DEFINE(struct pf_limit, pf_limits[PF_LIMIT_MAX]);
#define PACKET_LOOPED(pd) ((pd)->pf_mtag && \
(pd)->pf_mtag->flags & PF_PACKET_LOOPED)
#define STATE_LOOKUP(i, k, d, s, pd) \
do { \
(s) = pf_find_state((i), (k), (d)); \
if ((s) == NULL) \
return (PF_DROP); \
if (PACKET_LOOPED(pd)) \
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)
#define BOUND_IFACE(r, k) \
((r)->rule_flag & PFRULE_IFBOUND) ? (k) : V_pfi_all
#define STATE_INC_COUNTERS(s) \
do { \
counter_u64_add(s->rule.ptr->states_cur, 1); \
counter_u64_add(s->rule.ptr->states_tot, 1); \
if (s->anchor.ptr != NULL) { \
counter_u64_add(s->anchor.ptr->states_cur, 1); \
counter_u64_add(s->anchor.ptr->states_tot, 1); \
} \
if (s->nat_rule.ptr != NULL) { \
counter_u64_add(s->nat_rule.ptr->states_cur, 1);\
counter_u64_add(s->nat_rule.ptr->states_tot, 1);\
} \
} while (0)
#define STATE_DEC_COUNTERS(s) \
do { \
if (s->nat_rule.ptr != NULL) \
counter_u64_add(s->nat_rule.ptr->states_cur, -1);\
if (s->anchor.ptr != NULL) \
counter_u64_add(s->anchor.ptr->states_cur, -1); \
counter_u64_add(s->rule.ptr->states_cur, -1); \
} while (0)
static MALLOC_DEFINE(M_PFHASH, "pf_hash", "pf(4) hash header structures");
VNET_DEFINE(struct pf_keyhash *, pf_keyhash);
VNET_DEFINE(struct pf_idhash *, pf_idhash);
VNET_DEFINE(struct pf_srchash *, pf_srchash);
SYSCTL_NODE(_net, OID_AUTO, pf, CTLFLAG_RW, 0, "pf(4)");
u_long pf_hashmask;
u_long pf_srchashmask;
static u_long pf_hashsize;
static u_long pf_srchashsize;
SYSCTL_UINT(_net_pf, OID_AUTO, states_hashsize, CTLFLAG_RDTUN,
&pf_hashsize, 0, "Size of pf(4) states hashtable");
SYSCTL_UINT(_net_pf, OID_AUTO, source_nodes_hashsize, CTLFLAG_RDTUN,
&pf_srchashsize, 0, "Size of pf(4) source nodes hashtable");
VNET_DEFINE(void *, pf_swi_cookie);
VNET_DEFINE(uint32_t, pf_hashseed);
#define V_pf_hashseed VNET(pf_hashseed)
static __inline uint32_t
pf_hashkey(struct pf_state_key *sk)
{
uint32_t h;
h = jenkins_hash32((uint32_t *)sk,
sizeof(struct pf_state_key_cmp)/sizeof(uint32_t),
V_pf_hashseed);
return (h & pf_hashmask);
}
static __inline uint32_t
pf_hashsrc(struct pf_addr *addr, sa_family_t af)
{
uint32_t h;
switch (af) {
case AF_INET:
h = jenkins_hash32((uint32_t *)&addr->v4,
sizeof(addr->v4)/sizeof(uint32_t), V_pf_hashseed);
break;
case AF_INET6:
h = jenkins_hash32((uint32_t *)&addr->v6,
sizeof(addr->v6)/sizeof(uint32_t), V_pf_hashseed);
break;
default:
panic("%s: unknown address family %u", __func__, af);
}
return (h & pf_srchashmask);
}
#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 */
static 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_uptime;
}
static void
pf_add_threshold(struct pf_threshold *threshold)
{
u_int32_t t = time_uptime, 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;
}
static int
pf_check_threshold(struct pf_threshold *threshold)
{
return (threshold->count > threshold->limit);
}
static int
pf_src_connlimit(struct pf_state **state)
{
struct pf_overload_entry *pfoe;
int bad = 0;
PF_STATE_LOCK_ASSERT(*state);
(*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) {
V_pf_status.lcounters[LCNT_SRCCONN]++;
bad++;
}
if ((*state)->rule.ptr->max_src_conn_rate.limit &&
pf_check_threshold(&(*state)->src_node->conn_rate)) {
V_pf_status.lcounters[LCNT_SRCCONNRATE]++;
bad++;
}
if (!bad)
return (0);
/* Kill this state. */
(*state)->timeout = PFTM_PURGE;
(*state)->src.state = (*state)->dst.state = TCPS_CLOSED;
if ((*state)->rule.ptr->overload_tbl == NULL)
return (1);
/* Schedule overloading and flushing task. */
pfoe = malloc(sizeof(*pfoe), M_PFTEMP, M_NOWAIT);
if (pfoe == NULL)
return (1); /* too bad :( */
bcopy(&(*state)->src_node->addr, &pfoe->addr, sizeof(pfoe->addr));
pfoe->af = (*state)->key[PF_SK_WIRE]->af;
pfoe->rule = (*state)->rule.ptr;
pfoe->dir = (*state)->direction;
PF_OVERLOADQ_LOCK();
SLIST_INSERT_HEAD(&V_pf_overloadqueue, pfoe, next);
PF_OVERLOADQ_UNLOCK();
taskqueue_enqueue(taskqueue_swi, &V_pf_overloadtask);
return (1);
}
static void
pf_overload_task(void *v, int pending)
{
struct pf_overload_head queue;
struct pfr_addr p;
struct pf_overload_entry *pfoe, *pfoe1;
uint32_t killed = 0;
CURVNET_SET((struct vnet *)v);
PF_OVERLOADQ_LOCK();
queue = V_pf_overloadqueue;
SLIST_INIT(&V_pf_overloadqueue);
PF_OVERLOADQ_UNLOCK();
bzero(&p, sizeof(p));
SLIST_FOREACH(pfoe, &queue, next) {
V_pf_status.lcounters[LCNT_OVERLOAD_TABLE]++;
if (V_pf_status.debug >= PF_DEBUG_MISC) {
printf("%s: blocking address ", __func__);
pf_print_host(&pfoe->addr, 0, pfoe->af);
printf("\n");
}
p.pfra_af = pfoe->af;
switch (pfoe->af) {
#ifdef INET
case AF_INET:
p.pfra_net = 32;
p.pfra_ip4addr = pfoe->addr.v4;
break;
#endif
#ifdef INET6
case AF_INET6:
p.pfra_net = 128;
p.pfra_ip6addr = pfoe->addr.v6;
break;
#endif
}
PF_RULES_WLOCK();
pfr_insert_kentry(pfoe->rule->overload_tbl, &p, time_second);
PF_RULES_WUNLOCK();
}
/*
* Remove those entries, that don't need flushing.
*/
SLIST_FOREACH_SAFE(pfoe, &queue, next, pfoe1)
if (pfoe->rule->flush == 0) {
SLIST_REMOVE(&queue, pfoe, pf_overload_entry, next);
free(pfoe, M_PFTEMP);
} else
V_pf_status.lcounters[LCNT_OVERLOAD_FLUSH]++;
/* If nothing to flush, return. */
if (SLIST_EMPTY(&queue)) {
CURVNET_RESTORE();
return;
}
for (int i = 0; i <= pf_hashmask; i++) {
struct pf_idhash *ih = &V_pf_idhash[i];
struct pf_state_key *sk;
struct pf_state *s;
PF_HASHROW_LOCK(ih);
LIST_FOREACH(s, &ih->states, entry) {
sk = s->key[PF_SK_WIRE];
SLIST_FOREACH(pfoe, &queue, next)
if (sk->af == pfoe->af &&
((pfoe->rule->flush & PF_FLUSH_GLOBAL) ||
pfoe->rule == s->rule.ptr) &&
((pfoe->dir == PF_OUT &&
PF_AEQ(&pfoe->addr, &sk->addr[1], sk->af)) ||
(pfoe->dir == PF_IN &&
PF_AEQ(&pfoe->addr, &sk->addr[0], sk->af)))) {
s->timeout = PFTM_PURGE;
s->src.state = s->dst.state = TCPS_CLOSED;
killed++;
}
}
PF_HASHROW_UNLOCK(ih);
}
SLIST_FOREACH_SAFE(pfoe, &queue, next, pfoe1)
free(pfoe, M_PFTEMP);
if (V_pf_status.debug >= PF_DEBUG_MISC)
printf("%s: %u states killed", __func__, killed);
CURVNET_RESTORE();
}
/*
* Can return locked on failure, so that we can consistently
* allocate and insert a new one.
*/
struct pf_src_node *
pf_find_src_node(struct pf_addr *src, struct pf_rule *rule, sa_family_t af,
int returnlocked)
{
struct pf_srchash *sh;
struct pf_src_node *n;
V_pf_status.scounters[SCNT_SRC_NODE_SEARCH]++;
sh = &V_pf_srchash[pf_hashsrc(src, af)];
PF_HASHROW_LOCK(sh);
LIST_FOREACH(n, &sh->nodes, entry)
if (n->rule.ptr == rule && n->af == af &&
((af == AF_INET && n->addr.v4.s_addr == src->v4.s_addr) ||
(af == AF_INET6 && bcmp(&n->addr, src, sizeof(*src)) == 0)))
break;
if (n != NULL || returnlocked == 0)
PF_HASHROW_UNLOCK(sh);
return (n);
}
static int
pf_insert_src_node(struct pf_src_node **sn, struct pf_rule *rule,
struct pf_addr *src, sa_family_t af)
{
KASSERT((rule->rule_flag & PFRULE_RULESRCTRACK ||
rule->rpool.opts & PF_POOL_STICKYADDR),
("%s for non-tracking rule %p", __func__, rule));
if (*sn == NULL)
*sn = pf_find_src_node(src, rule, af, 1);
if (*sn == NULL) {
struct pf_srchash *sh = &V_pf_srchash[pf_hashsrc(src, af)];
PF_HASHROW_ASSERT(sh);
if (!rule->max_src_nodes ||
counter_u64_fetch(rule->src_nodes) < rule->max_src_nodes)
(*sn) = uma_zalloc(V_pf_sources_z, M_NOWAIT | M_ZERO);
else
V_pf_status.lcounters[LCNT_SRCNODES]++;
if ((*sn) == NULL) {
PF_HASHROW_UNLOCK(sh);
return (-1);
}
pf_init_threshold(&(*sn)->conn_rate,
rule->max_src_conn_rate.limit,
rule->max_src_conn_rate.seconds);
(*sn)->af = af;
(*sn)->rule.ptr = rule;
PF_ACPY(&(*sn)->addr, src, af);
LIST_INSERT_HEAD(&sh->nodes, *sn, entry);
(*sn)->creation = time_uptime;
(*sn)->ruletype = rule->action;
if ((*sn)->rule.ptr != NULL)
counter_u64_add((*sn)->rule.ptr->src_nodes, 1);
PF_HASHROW_UNLOCK(sh);
V_pf_status.scounters[SCNT_SRC_NODE_INSERT]++;
V_pf_status.src_nodes++;
} else {
if (rule->max_src_states &&
(*sn)->states >= rule->max_src_states) {
V_pf_status.lcounters[LCNT_SRCSTATES]++;
return (-1);
}
}
return (0);
}
void
pf_unlink_src_node_locked(struct pf_src_node *src)
{
#ifdef INVARIANTS
struct pf_srchash *sh;
sh = &V_pf_srchash[pf_hashsrc(&src->addr, src->af)];
PF_HASHROW_ASSERT(sh);
#endif
LIST_REMOVE(src, entry);
if (src->rule.ptr)
counter_u64_add(src->rule.ptr->src_nodes, -1);
V_pf_status.scounters[SCNT_SRC_NODE_REMOVALS]++;
V_pf_status.src_nodes--;
}
void
pf_unlink_src_node(struct pf_src_node *src)
{
struct pf_srchash *sh;
sh = &V_pf_srchash[pf_hashsrc(&src->addr, src->af)];
PF_HASHROW_LOCK(sh);
pf_unlink_src_node_locked(src);
PF_HASHROW_UNLOCK(sh);
}
static void
pf_free_src_node(struct pf_src_node *sn)
{
KASSERT(sn->states == 0, ("%s: %p has refs", __func__, sn));
uma_zfree(V_pf_sources_z, sn);
}
u_int
pf_free_src_nodes(struct pf_src_node_list *head)
{
struct pf_src_node *sn, *tmp;
u_int count = 0;
LIST_FOREACH_SAFE(sn, head, entry, tmp) {
pf_free_src_node(sn);
count++;
}
return (count);
}
void
pf_mtag_initialize()
{
pf_mtag_z = uma_zcreate("pf mtags", sizeof(struct m_tag) +
sizeof(struct pf_mtag), NULL, NULL, pf_mtag_uminit, NULL,
UMA_ALIGN_PTR, 0);
}
/* Per-vnet data storage structures initialization. */
void
pf_initialize()
{
struct pf_keyhash *kh;
struct pf_idhash *ih;
struct pf_srchash *sh;
u_int i;
if (pf_hashsize == 0 || !powerof2(pf_hashsize))
pf_hashsize = PF_HASHSIZ;
if (pf_srchashsize == 0 || !powerof2(pf_srchashsize))
pf_srchashsize = PF_HASHSIZ / 4;
V_pf_hashseed = arc4random();
/* States and state keys storage. */
V_pf_state_z = uma_zcreate("pf states", sizeof(struct pf_state),
NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
V_pf_limits[PF_LIMIT_STATES].zone = V_pf_state_z;
uma_zone_set_max(V_pf_state_z, PFSTATE_HIWAT);
uma_zone_set_warning(V_pf_state_z, "PF states limit reached");
V_pf_state_key_z = uma_zcreate("pf state keys",
sizeof(struct pf_state_key), pf_state_key_ctor, NULL, NULL, NULL,
UMA_ALIGN_PTR, 0);
V_pf_keyhash = malloc(pf_hashsize * sizeof(struct pf_keyhash),
M_PFHASH, M_WAITOK | M_ZERO);
V_pf_idhash = malloc(pf_hashsize * sizeof(struct pf_idhash),
M_PFHASH, M_WAITOK | M_ZERO);
pf_hashmask = pf_hashsize - 1;
for (i = 0, kh = V_pf_keyhash, ih = V_pf_idhash; i <= pf_hashmask;
i++, kh++, ih++) {
mtx_init(&kh->lock, "pf_keyhash", NULL, MTX_DEF | MTX_DUPOK);
mtx_init(&ih->lock, "pf_idhash", NULL, MTX_DEF);
}
/* Source nodes. */
V_pf_sources_z = uma_zcreate("pf source nodes",
sizeof(struct pf_src_node), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR,
0);
V_pf_limits[PF_LIMIT_SRC_NODES].zone = V_pf_sources_z;
uma_zone_set_max(V_pf_sources_z, PFSNODE_HIWAT);
uma_zone_set_warning(V_pf_sources_z, "PF source nodes limit reached");
V_pf_srchash = malloc(pf_srchashsize * sizeof(struct pf_srchash),
M_PFHASH, M_WAITOK|M_ZERO);
pf_srchashmask = pf_srchashsize - 1;
for (i = 0, sh = V_pf_srchash; i <= pf_srchashmask; i++, sh++)
mtx_init(&sh->lock, "pf_srchash", NULL, MTX_DEF);
/* ALTQ */
TAILQ_INIT(&V_pf_altqs[0]);
TAILQ_INIT(&V_pf_altqs[1]);
TAILQ_INIT(&V_pf_pabuf);
V_pf_altqs_active = &V_pf_altqs[0];
V_pf_altqs_inactive = &V_pf_altqs[1];
/* Send & overload+flush queues. */
STAILQ_INIT(&V_pf_sendqueue);
SLIST_INIT(&V_pf_overloadqueue);
TASK_INIT(&V_pf_overloadtask, 0, pf_overload_task, curvnet);
mtx_init(&pf_sendqueue_mtx, "pf send queue", NULL, MTX_DEF);
mtx_init(&pf_overloadqueue_mtx, "pf overload/flush queue", NULL,
MTX_DEF);
/* Unlinked, but may be referenced rules. */
TAILQ_INIT(&V_pf_unlinked_rules);
mtx_init(&pf_unlnkdrules_mtx, "pf unlinked rules", NULL, MTX_DEF);
}
void
pf_mtag_cleanup()
{
uma_zdestroy(pf_mtag_z);
}
void
pf_cleanup()
{
struct pf_keyhash *kh;
struct pf_idhash *ih;
struct pf_srchash *sh;
struct pf_send_entry *pfse, *next;
u_int i;
for (i = 0, kh = V_pf_keyhash, ih = V_pf_idhash; i <= pf_hashmask;
i++, kh++, ih++) {
KASSERT(LIST_EMPTY(&kh->keys), ("%s: key hash not empty",
__func__));
KASSERT(LIST_EMPTY(&ih->states), ("%s: id hash not empty",
__func__));
mtx_destroy(&kh->lock);
mtx_destroy(&ih->lock);
}
free(V_pf_keyhash, M_PFHASH);
free(V_pf_idhash, M_PFHASH);
for (i = 0, sh = V_pf_srchash; i <= pf_srchashmask; i++, sh++) {
KASSERT(LIST_EMPTY(&sh->nodes),
("%s: source node hash not empty", __func__));
mtx_destroy(&sh->lock);
}
free(V_pf_srchash, M_PFHASH);
STAILQ_FOREACH_SAFE(pfse, &V_pf_sendqueue, pfse_next, next) {
m_freem(pfse->pfse_m);
free(pfse, M_PFTEMP);
}
mtx_destroy(&pf_sendqueue_mtx);
mtx_destroy(&pf_overloadqueue_mtx);
mtx_destroy(&pf_unlnkdrules_mtx);
uma_zdestroy(V_pf_sources_z);
uma_zdestroy(V_pf_state_z);
uma_zdestroy(V_pf_state_key_z);
}
static int
pf_mtag_uminit(void *mem, int size, int how)
{
struct m_tag *t;
t = (struct m_tag *)mem;
t->m_tag_cookie = MTAG_ABI_COMPAT;
t->m_tag_id = PACKET_TAG_PF;
t->m_tag_len = sizeof(struct pf_mtag);
t->m_tag_free = pf_mtag_free;
return (0);
}
static void
pf_mtag_free(struct m_tag *t)
{
uma_zfree(pf_mtag_z, t);
}
struct pf_mtag *
pf_get_mtag(struct mbuf *m)
{
struct m_tag *mtag;
if ((mtag = m_tag_find(m, PACKET_TAG_PF, NULL)) != NULL)
return ((struct pf_mtag *)(mtag + 1));
mtag = uma_zalloc(pf_mtag_z, M_NOWAIT);
if (mtag == NULL)
return (NULL);
bzero(mtag + 1, sizeof(struct pf_mtag));
m_tag_prepend(m, mtag);
return ((struct pf_mtag *)(mtag + 1));
}
static int
pf_state_key_attach(struct pf_state_key *skw, struct pf_state_key *sks,
struct pf_state *s)
{
struct pf_keyhash *khs, *khw, *kh;
struct pf_state_key *sk, *cur;
struct pf_state *si, *olds = NULL;
int idx;
KASSERT(s->refs == 0, ("%s: state not pristine", __func__));
KASSERT(s->key[PF_SK_WIRE] == NULL, ("%s: state has key", __func__));
KASSERT(s->key[PF_SK_STACK] == NULL, ("%s: state has key", __func__));
/*
* We need to lock hash slots of both keys. To avoid deadlock
* we always lock the slot with lower address first. Unlock order
* isn't important.
*
* We also need to lock ID hash slot before dropping key
* locks. On success we return with ID hash slot locked.
*/
if (skw == sks) {
khs = khw = &V_pf_keyhash[pf_hashkey(skw)];
PF_HASHROW_LOCK(khs);
} else {
khs = &V_pf_keyhash[pf_hashkey(sks)];
khw = &V_pf_keyhash[pf_hashkey(skw)];
if (khs == khw) {
PF_HASHROW_LOCK(khs);
} else if (khs < khw) {
PF_HASHROW_LOCK(khs);
PF_HASHROW_LOCK(khw);
} else {
PF_HASHROW_LOCK(khw);
PF_HASHROW_LOCK(khs);
}
}
#define KEYS_UNLOCK() do { \
if (khs != khw) { \
PF_HASHROW_UNLOCK(khs); \
PF_HASHROW_UNLOCK(khw); \
} else \
PF_HASHROW_UNLOCK(khs); \
} while (0)
/*
* First run: start with wire key.
*/
sk = skw;
kh = khw;
idx = PF_SK_WIRE;
keyattach:
LIST_FOREACH(cur, &kh->keys, entry)
if (bcmp(cur, sk, sizeof(struct pf_state_key_cmp)) == 0)
break;
if (cur != NULL) {
/* Key exists. Check for same kif, if none, add to key. */
TAILQ_FOREACH(si, &cur->states[idx], key_list[idx]) {
struct pf_idhash *ih = &V_pf_idhash[PF_IDHASH(si)];
PF_HASHROW_LOCK(ih);
if (si->kif == s->kif &&
si->direction == s->direction) {
if (sk->proto == IPPROTO_TCP &&
si->src.state >= TCPS_FIN_WAIT_2 &&
si->dst.state >= TCPS_FIN_WAIT_2) {
/*
* New state matches an old >FIN_WAIT_2
* state. We can't drop key hash locks,
* thus we can't unlink it properly.
*
* As a workaround we drop it into
* TCPS_CLOSED state, schedule purge
* ASAP and push it into the very end
* of the slot TAILQ, so that it won't
* conflict with our new state.
*/
si->src.state = si->dst.state =
TCPS_CLOSED;
si->timeout = PFTM_PURGE;
olds = si;
} else {
if (V_pf_status.debug >= PF_DEBUG_MISC) {
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,
(idx == PF_SK_WIRE) ?
sk : NULL,
(idx == PF_SK_STACK) ?
sk : NULL);
printf("\n");
}
PF_HASHROW_UNLOCK(ih);
KEYS_UNLOCK();
uma_zfree(V_pf_state_key_z, sk);
if (idx == PF_SK_STACK)
pf_detach_state(s);
return (EEXIST); /* collision! */
}
}
PF_HASHROW_UNLOCK(ih);
}
uma_zfree(V_pf_state_key_z, sk);
s->key[idx] = cur;
} else {
LIST_INSERT_HEAD(&kh->keys, sk, entry);
s->key[idx] = sk;
}
stateattach:
/* List is sorted, if-bound states before floating. */
if (s->kif == V_pfi_all)
TAILQ_INSERT_TAIL(&s->key[idx]->states[idx], s, key_list[idx]);
else
TAILQ_INSERT_HEAD(&s->key[idx]->states[idx], s, key_list[idx]);
if (olds) {
TAILQ_REMOVE(&s->key[idx]->states[idx], olds, key_list[idx]);
TAILQ_INSERT_TAIL(&s->key[idx]->states[idx], olds,
key_list[idx]);
olds = NULL;
}
/*
* Attach done. See how should we (or should not?)
* attach a second key.
*/
if (sks == skw) {
s->key[PF_SK_STACK] = s->key[PF_SK_WIRE];
idx = PF_SK_STACK;
sks = NULL;
goto stateattach;
} else if (sks != NULL) {
/*
* Continue attaching with stack key.
*/
sk = sks;
kh = khs;
idx = PF_SK_STACK;
sks = NULL;
goto keyattach;
}
PF_STATE_LOCK(s);
KEYS_UNLOCK();
KASSERT(s->key[PF_SK_WIRE] != NULL && s->key[PF_SK_STACK] != NULL,
("%s failure", __func__));
return (0);
#undef KEYS_UNLOCK
}
static void
pf_detach_state(struct pf_state *s)
{
struct pf_state_key *sks = s->key[PF_SK_STACK];
struct pf_keyhash *kh;
if (sks != NULL) {
kh = &V_pf_keyhash[pf_hashkey(sks)];
PF_HASHROW_LOCK(kh);
if (s->key[PF_SK_STACK] != NULL)
pf_state_key_detach(s, PF_SK_STACK);
/*
* If both point to same key, then we are done.
*/
if (sks == s->key[PF_SK_WIRE]) {
pf_state_key_detach(s, PF_SK_WIRE);
PF_HASHROW_UNLOCK(kh);
return;
}
PF_HASHROW_UNLOCK(kh);
}
if (s->key[PF_SK_WIRE] != NULL) {
kh = &V_pf_keyhash[pf_hashkey(s->key[PF_SK_WIRE])];
PF_HASHROW_LOCK(kh);
if (s->key[PF_SK_WIRE] != NULL)
pf_state_key_detach(s, PF_SK_WIRE);
PF_HASHROW_UNLOCK(kh);
}
}
static void
pf_state_key_detach(struct pf_state *s, int idx)
{
struct pf_state_key *sk = s->key[idx];
#ifdef INVARIANTS
struct pf_keyhash *kh = &V_pf_keyhash[pf_hashkey(sk)];
PF_HASHROW_ASSERT(kh);
#endif
TAILQ_REMOVE(&sk->states[idx], s, key_list[idx]);
s->key[idx] = NULL;
if (TAILQ_EMPTY(&sk->states[0]) && TAILQ_EMPTY(&sk->states[1])) {
LIST_REMOVE(sk, entry);
uma_zfree(V_pf_state_key_z, sk);
}
}
static int
pf_state_key_ctor(void *mem, int size, void *arg, int flags)
{
struct pf_state_key *sk = mem;
bzero(sk, sizeof(struct pf_state_key_cmp));
TAILQ_INIT(&sk->states[PF_SK_WIRE]);
TAILQ_INIT(&sk->states[PF_SK_STACK]);
return (0);
}
struct pf_state_key *
pf_state_key_setup(struct pf_pdesc *pd, struct pf_addr *saddr,
struct pf_addr *daddr, u_int16_t sport, u_int16_t dport)
{
struct pf_state_key *sk;
sk = uma_zalloc(V_pf_state_key_z, M_NOWAIT);
if (sk == NULL)
return (NULL);
PF_ACPY(&sk->addr[pd->sidx], saddr, pd->af);
PF_ACPY(&sk->addr[pd->didx], daddr, pd->af);
sk->port[pd->sidx] = sport;
sk->port[pd->didx] = dport;
sk->proto = pd->proto;
sk->af = pd->af;
return (sk);
}
struct pf_state_key *
pf_state_key_clone(struct pf_state_key *orig)
{
struct pf_state_key *sk;
sk = uma_zalloc(V_pf_state_key_z, M_NOWAIT);
if (sk == NULL)
return (NULL);
bcopy(orig, sk, sizeof(struct pf_state_key_cmp));
return (sk);
}
int
pf_state_insert(struct pfi_kif *kif, struct pf_state_key *skw,
struct pf_state_key *sks, struct pf_state *s)
{
struct pf_idhash *ih;
struct pf_state *cur;
int error;
KASSERT(TAILQ_EMPTY(&sks->states[0]) && TAILQ_EMPTY(&sks->states[1]),
("%s: sks not pristine", __func__));
KASSERT(TAILQ_EMPTY(&skw->states[0]) && TAILQ_EMPTY(&skw->states[1]),
("%s: skw not pristine", __func__));
KASSERT(s->refs == 0, ("%s: state not pristine", __func__));
s->kif = kif;
if (s->id == 0 && s->creatorid == 0) {
/* XXX: should be atomic, but probability of collision low */
if ((s->id = V_pf_stateid[curcpu]++) == PFID_MAXID)
V_pf_stateid[curcpu] = 1;
s->id |= (uint64_t )curcpu << PFID_CPUSHIFT;
s->id = htobe64(s->id);
s->creatorid = V_pf_status.hostid;
}
/* Returns with ID locked on success. */
if ((error = pf_state_key_attach(skw, sks, s)) != 0)
return (error);
ih = &V_pf_idhash[PF_IDHASH(s)];
PF_HASHROW_ASSERT(ih);
LIST_FOREACH(cur, &ih->states, entry)
if (cur->id == s->id && cur->creatorid == s->creatorid)
break;
if (cur != NULL) {
PF_HASHROW_UNLOCK(ih);
if (V_pf_status.debug >= PF_DEBUG_MISC) {
printf("pf: state ID collision: "
"id: %016llx creatorid: %08x\n",
(unsigned long long)be64toh(s->id),
ntohl(s->creatorid));
}
pf_detach_state(s);
return (EEXIST);
}
LIST_INSERT_HEAD(&ih->states, s, entry);
/* One for keys, one for ID hash. */
refcount_init(&s->refs, 2);
V_pf_status.fcounters[FCNT_STATE_INSERT]++;
if (pfsync_insert_state_ptr != NULL)
pfsync_insert_state_ptr(s);
/* Returns locked. */
return (0);
}
/*
* Find state by ID: returns with locked row on success.
*/
struct pf_state *
pf_find_state_byid(uint64_t id, uint32_t creatorid)
{
struct pf_idhash *ih;
struct pf_state *s;
V_pf_status.fcounters[FCNT_STATE_SEARCH]++;
ih = &V_pf_idhash[(be64toh(id) % (pf_hashmask + 1))];
PF_HASHROW_LOCK(ih);
LIST_FOREACH(s, &ih->states, entry)
if (s->id == id && s->creatorid == creatorid)
break;
if (s == NULL)
PF_HASHROW_UNLOCK(ih);
return (s);
}
/*
* Find state by key.
* Returns with ID hash slot locked on success.
*/
static struct pf_state *
pf_find_state(struct pfi_kif *kif, struct pf_state_key_cmp *key, u_int dir)
{
struct pf_keyhash *kh;
struct pf_state_key *sk;
struct pf_state *s;
int idx;
V_pf_status.fcounters[FCNT_STATE_SEARCH]++;
kh = &V_pf_keyhash[pf_hashkey((struct pf_state_key *)key)];
PF_HASHROW_LOCK(kh);
LIST_FOREACH(sk, &kh->keys, entry)
if (bcmp(sk, key, sizeof(struct pf_state_key_cmp)) == 0)
break;
if (sk == NULL) {
PF_HASHROW_UNLOCK(kh);
return (NULL);
}
idx = (dir == PF_IN ? PF_SK_WIRE : PF_SK_STACK);
/* List is sorted, if-bound states before floating ones. */
TAILQ_FOREACH(s, &sk->states[idx], key_list[idx])
if (s->kif == V_pfi_all || s->kif == kif) {
PF_STATE_LOCK(s);
PF_HASHROW_UNLOCK(kh);
if (s->timeout >= PFTM_MAX) {
/*
* State is either being processed by
* pf_unlink_state() in an other thread, or
* is scheduled for immediate expiry.
*/
PF_STATE_UNLOCK(s);
return (NULL);
}
return (s);
}
PF_HASHROW_UNLOCK(kh);
return (NULL);
}
struct pf_state *
pf_find_state_all(struct pf_state_key_cmp *key, u_int dir, int *more)
{
struct pf_keyhash *kh;
struct pf_state_key *sk;
struct pf_state *s, *ret = NULL;
int idx, inout = 0;
V_pf_status.fcounters[FCNT_STATE_SEARCH]++;
kh = &V_pf_keyhash[pf_hashkey((struct pf_state_key *)key)];
PF_HASHROW_LOCK(kh);
LIST_FOREACH(sk, &kh->keys, entry)
if (bcmp(sk, key, sizeof(struct pf_state_key_cmp)) == 0)
break;
if (sk == NULL) {
PF_HASHROW_UNLOCK(kh);
return (NULL);
}
switch (dir) {
case PF_IN:
idx = PF_SK_WIRE;
break;
case PF_OUT:
idx = PF_SK_STACK;
break;
case PF_INOUT:
idx = PF_SK_WIRE;
inout = 1;
break;
default:
panic("%s: dir %u", __func__, dir);
}
second_run:
TAILQ_FOREACH(s, &sk->states[idx], key_list[idx]) {
if (more == NULL) {
PF_HASHROW_UNLOCK(kh);
return (s);
}
if (ret)
(*more)++;
else
ret = s;
}
if (inout == 1) {
inout = 0;
idx = PF_SK_STACK;
goto second_run;
}
PF_HASHROW_UNLOCK(kh);
return (ret);
}
/* END state table stuff */
static void
pf_send(struct pf_send_entry *pfse)
{
PF_SENDQ_LOCK();
STAILQ_INSERT_TAIL(&V_pf_sendqueue, pfse, pfse_next);
PF_SENDQ_UNLOCK();
swi_sched(V_pf_swi_cookie, 0);
}
void
pf_intr(void *v)
{
struct pf_send_head queue;
struct pf_send_entry *pfse, *next;
CURVNET_SET((struct vnet *)v);
PF_SENDQ_LOCK();
queue = V_pf_sendqueue;
STAILQ_INIT(&V_pf_sendqueue);
PF_SENDQ_UNLOCK();
STAILQ_FOREACH_SAFE(pfse, &queue, pfse_next, next) {
switch (pfse->pfse_type) {
#ifdef INET
case PFSE_IP:
ip_output(pfse->pfse_m, NULL, NULL, 0, NULL, NULL);
break;
case PFSE_ICMP:
icmp_error(pfse->pfse_m, pfse->pfse_icmp_type,
pfse->pfse_icmp_code, 0, pfse->pfse_icmp_mtu);
break;
#endif /* INET */
#ifdef INET6
case PFSE_IP6:
ip6_output(pfse->pfse_m, NULL, NULL, 0, NULL, NULL,
NULL);
break;
case PFSE_ICMP6:
icmp6_error(pfse->pfse_m, pfse->pfse_icmp_type,
pfse->pfse_icmp_code, pfse->pfse_icmp_mtu);
break;
#endif /* INET6 */
default:
panic("%s: unknown type", __func__);
}
free(pfse, M_PFTEMP);
}
CURVNET_RESTORE();
}
void
pf_purge_thread(void *v)
{
u_int idx = 0;
CURVNET_SET((struct vnet *)v);
for (;;) {
PF_RULES_RLOCK();
rw_sleep(pf_purge_thread, &pf_rules_lock, 0, "pftm", hz / 10);
if (V_pf_end_threads) {
/*
* To cleanse up all kifs and rules we need
* two runs: first one clears reference flags,
* then pf_purge_expired_states() doesn't
* raise them, and then second run frees.
*/
PF_RULES_RUNLOCK();
pf_purge_unlinked_rules();
pfi_kif_purge();
/*
* Now purge everything.
*/
pf_purge_expired_states(0, pf_hashmask);
pf_purge_expired_fragments();
pf_purge_expired_src_nodes();
/*
* Now all kifs & rules should be unreferenced,
* thus should be successfully freed.
*/
pf_purge_unlinked_rules();
pfi_kif_purge();
/*
* Announce success and exit.
*/
PF_RULES_RLOCK();
V_pf_end_threads++;
PF_RULES_RUNLOCK();
wakeup(pf_purge_thread);
kproc_exit(0);
}
PF_RULES_RUNLOCK();
/* Process 1/interval fraction of the state table every run. */
idx = pf_purge_expired_states(idx, pf_hashmask /
(V_pf_default_rule.timeout[PFTM_INTERVAL] * 10));
/* Purge other expired types every PFTM_INTERVAL seconds. */
if (idx == 0) {
/*
* Order is important:
* - states and src nodes reference rules
* - states and rules reference kifs
*/
pf_purge_expired_fragments();
pf_purge_expired_src_nodes();
pf_purge_unlinked_rules();
pfi_kif_purge();
}
}
/* not reached */
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_uptime);
KASSERT(state->timeout != PFTM_UNLINKED,
("pf_state_expires: timeout == PFTM_UNLINKED"));
KASSERT((state->timeout < PFTM_MAX),
("pf_state_expires: timeout > PFTM_MAX"));
timeout = state->rule.ptr->timeout[state->timeout];
if (!timeout)
timeout = V_pf_default_rule.timeout[state->timeout];
start = state->rule.ptr->timeout[PFTM_ADAPTIVE_START];
if (start) {
end = state->rule.ptr->timeout[PFTM_ADAPTIVE_END];
states = counter_u64_fetch(state->rule.ptr->states_cur);
} else {
start = V_pf_default_rule.timeout[PFTM_ADAPTIVE_START];
end = V_pf_default_rule.timeout[PFTM_ADAPTIVE_END];
states = V_pf_status.states;
}
if (end && states > start && start < end) {
if (states < end)
return (state->expire + timeout * (end - states) /
(end - start));
else
return (time_uptime);
}
return (state->expire + timeout);
}
void
pf_purge_expired_src_nodes()
{
struct pf_src_node_list freelist;
struct pf_srchash *sh;
struct pf_src_node *cur, *next;
int i;
LIST_INIT(&freelist);
for (i = 0, sh = V_pf_srchash; i <= pf_srchashmask; i++, sh++) {
PF_HASHROW_LOCK(sh);
LIST_FOREACH_SAFE(cur, &sh->nodes, entry, next)
if (cur->states == 0 && cur->expire <= time_uptime) {
pf_unlink_src_node_locked(cur);
LIST_INSERT_HEAD(&freelist, cur, entry);
} else if (cur->rule.ptr != NULL)
cur->rule.ptr->rule_flag |= PFRULE_REFS;
PF_HASHROW_UNLOCK(sh);
}
pf_free_src_nodes(&freelist);
}
static 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 =
V_pf_default_rule.timeout[PFTM_SRC_NODE];
s->src_node->expire = time_uptime + 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 =
V_pf_default_rule.timeout[PFTM_SRC_NODE];
s->nat_src_node->expire = time_uptime + timeout;
}
}
s->src_node = s->nat_src_node = NULL;
}
/*
* Unlink and potentilly free a state. Function may be
* called with ID hash row locked, but always returns
* unlocked, since it needs to go through key hash locking.
*/
int
pf_unlink_state(struct pf_state *s, u_int flags)
{
struct pf_idhash *ih = &V_pf_idhash[PF_IDHASH(s)];
if ((flags & PF_ENTER_LOCKED) == 0)
PF_HASHROW_LOCK(ih);
else
PF_HASHROW_ASSERT(ih);
if (s->timeout == PFTM_UNLINKED) {
/*
* State is being processed
* by pf_unlink_state() in
* an other thread.
*/
PF_HASHROW_UNLOCK(ih);
return (0); /* XXXGL: undefined actually */
}
if (s->src.state == PF_TCPS_PROXY_DST) {
/* XXX wire key the right one? */
pf_send_tcp(NULL, s->rule.ptr, s->key[PF_SK_WIRE]->af,
&s->key[PF_SK_WIRE]->addr[1],
&s->key[PF_SK_WIRE]->addr[0],
s->key[PF_SK_WIRE]->port[1],
s->key[PF_SK_WIRE]->port[0],
s->src.seqhi, s->src.seqlo + 1,
TH_RST|TH_ACK, 0, 0, 0, 1, s->tag, NULL);
}
LIST_REMOVE(s, entry);
pf_src_tree_remove_state(s);
if (pfsync_delete_state_ptr != NULL)
pfsync_delete_state_ptr(s);
STATE_DEC_COUNTERS(s);
s->timeout = PFTM_UNLINKED;
PF_HASHROW_UNLOCK(ih);
pf_detach_state(s);
refcount_release(&s->refs);
return (pf_release_state(s));
}
void
pf_free_state(struct pf_state *cur)
{
KASSERT(cur->refs == 0, ("%s: %p has refs", __func__, cur));
KASSERT(cur->timeout == PFTM_UNLINKED, ("%s: timeout %u", __func__,
cur->timeout));
pf_normalize_tcp_cleanup(cur);
uma_zfree(V_pf_state_z, cur);
V_pf_status.fcounters[FCNT_STATE_REMOVALS]++;
}
/*
* Called only from pf_purge_thread(), thus serialized.
*/
static u_int
pf_purge_expired_states(u_int i, int maxcheck)
{
struct pf_idhash *ih;
struct pf_state *s;
V_pf_status.states = uma_zone_get_cur(V_pf_state_z);
/*
* Go through hash and unlink states that expire now.
*/
while (maxcheck > 0) {
ih = &V_pf_idhash[i];
relock:
PF_HASHROW_LOCK(ih);
LIST_FOREACH(s, &ih->states, entry) {
if (pf_state_expires(s) <= time_uptime) {
V_pf_status.states -=
pf_unlink_state(s, PF_ENTER_LOCKED);
goto relock;
}
s->rule.ptr->rule_flag |= PFRULE_REFS;
if (s->nat_rule.ptr != NULL)
s->nat_rule.ptr->rule_flag |= PFRULE_REFS;
if (s->anchor.ptr != NULL)
s->anchor.ptr->rule_flag |= PFRULE_REFS;
s->kif->pfik_flags |= PFI_IFLAG_REFS;
if (s->rt_kif)
s->rt_kif->pfik_flags |= PFI_IFLAG_REFS;
}
PF_HASHROW_UNLOCK(ih);
/* Return when we hit end of hash. */
if (++i > pf_hashmask) {
V_pf_status.states = uma_zone_get_cur(V_pf_state_z);
return (0);
}
maxcheck--;
}
V_pf_status.states = uma_zone_get_cur(V_pf_state_z);
return (i);
}
static void
pf_purge_unlinked_rules()
{
struct pf_rulequeue tmpq;
struct pf_rule *r, *r1;
/*
* If we have overloading task pending, then we'd
* better skip purging this time. There is a tiny
* probability that overloading task references
* an already unlinked rule.
*/
PF_OVERLOADQ_LOCK();
if (!SLIST_EMPTY(&V_pf_overloadqueue)) {
PF_OVERLOADQ_UNLOCK();
return;
}
PF_OVERLOADQ_UNLOCK();
/*
* Do naive mark-and-sweep garbage collecting of old rules.
* Reference flag is raised by pf_purge_expired_states()
* and pf_purge_expired_src_nodes().
*
* To avoid LOR between PF_UNLNKDRULES_LOCK/PF_RULES_WLOCK,
* use a temporary queue.
*/
TAILQ_INIT(&tmpq);
PF_UNLNKDRULES_LOCK();
TAILQ_FOREACH_SAFE(r, &V_pf_unlinked_rules, entries, r1) {
if (!(r->rule_flag & PFRULE_REFS)) {
TAILQ_REMOVE(&V_pf_unlinked_rules, r, entries);
TAILQ_INSERT_TAIL(&tmpq, r, entries);
} else
r->rule_flag &= ~PFRULE_REFS;
}
PF_UNLNKDRULES_UNLOCK();
if (!TAILQ_EMPTY(&tmpq)) {
PF_RULES_WLOCK();
TAILQ_FOREACH_SAFE(r, &tmpq, entries, r1) {
TAILQ_REMOVE(&tmpq, r, entries);
pf_free_rule(r);
}
PF_RULES_WUNLOCK();
}
}
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);
}
static 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);
}
static 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);
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);
}
static 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
static 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 */
static 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)
*/
static 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;
u_int8_t opts[TCP_MAXOLEN], *opt = opts;
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)
m_copyback(m, off + sizeof(*th), thoptlen, (caddr_t)opts);
return (copyback);
}
static void
pf_send_tcp(struct mbuf *replyto, const struct pf_rule *r, sa_family_t af,
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 ifnet *ifp)
{
struct pf_send_entry *pfse;
struct mbuf *m;
int len, tlen;
#ifdef INET
struct ip *h = NULL;
#endif /* INET */
#ifdef INET6
struct ip6_hdr *h6 = NULL;
#endif /* INET6 */
struct tcphdr *th;
char *opt;
struct pf_mtag *pf_mtag;
len = 0;
th = NULL;
/* 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 */
default:
panic("%s: unsupported af %d", __func__, af);
}
/* Allocate outgoing queue entry, mbuf and mbuf tag. */
pfse = malloc(sizeof(*pfse), M_PFTEMP, M_NOWAIT);
if (pfse == NULL)
return;
m = m_gethdr(M_NOWAIT, MT_DATA);
if (m == NULL) {
free(pfse, M_PFTEMP);
return;
}
#ifdef MAC
mac_netinet_firewall_send(m);
#endif
if ((pf_mtag = pf_get_mtag(m)) == NULL) {
free(pfse, M_PFTEMP);
m_freem(m);
return;
}
if (tag)
m->m_flags |= M_SKIP_FIREWALL;
pf_mtag->tag = rtag;
if (r != NULL && r->rtableid >= 0)
M_SETFIB(m, r->rtableid);
#ifdef ALTQ
if (r != NULL && r->qid) {
pf_mtag->qid = r->qid;
/* add hints for ecn */
pf_mtag->hdr = mtod(m, struct ip *);
}
#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;
h->ip_off = htons(V_path_mtu_discovery ? IP_DF : 0);
h->ip_len = htons(len);
h->ip_ttl = ttl ? ttl : V_ip_defttl;
h->ip_sum = 0;
pfse->pfse_type = PFSE_IP;
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;
pfse->pfse_type = PFSE_IP6;
break;
#endif /* INET6 */
}
pfse->pfse_m = m;
pf_send(pfse);
}
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 pf_send_entry *pfse;
struct mbuf *m0;
struct pf_mtag *pf_mtag;
/* Allocate outgoing queue entry, mbuf and mbuf tag. */
pfse = malloc(sizeof(*pfse), M_PFTEMP, M_NOWAIT);
if (pfse == NULL)
return;
if ((m0 = m_copypacket(m, M_NOWAIT)) == NULL) {
free(pfse, M_PFTEMP);
return;
}
if ((pf_mtag = pf_get_mtag(m0)) == NULL) {
free(pfse, M_PFTEMP);
return;
}
/* XXX: revisit */
m0->m_flags |= M_SKIP_FIREWALL;
if (r->rtableid >= 0)
M_SETFIB(m0, r->rtableid);
#ifdef ALTQ
if (r->qid) {
pf_mtag->qid = r->qid;
/* add hints for ecn */
pf_mtag->hdr = mtod(m0, struct ip *);
}
#endif /* ALTQ */
switch (af) {
#ifdef INET
case AF_INET:
pfse->pfse_type = PFSE_ICMP;
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
pfse->pfse_type = PFSE_ICMP6;
break;
#endif /* INET6 */
}
pfse->pfse_m = m0;
pfse->pfse_icmp_type = type;
pfse->pfse_icmp_code = code;
pf_send(pfse);
}
/*
* 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);
}
static 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));
}
static 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));
}
static 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
pf_match_tag(struct mbuf *m, struct pf_rule *r, int *tag, int mtag)
{
if (*tag == -1)
*tag = mtag;
return ((!r->match_tag_not && r->match_tag == *tag) ||
(r->match_tag_not && r->match_tag != *tag));
}
int
pf_tag_packet(struct mbuf *m, struct pf_pdesc *pd, int tag)
{
KASSERT(tag > 0, ("%s: tag %d", __func__, tag));
if (pd->pf_mtag == NULL && ((pd->pf_mtag = pf_get_mtag(m)) == NULL))
return (ENOMEM);
pd->pf_mtag->tag = tag;
return (0);
}
#define PF_ANCHOR_STACKSIZE 32
struct pf_anchor_stackframe {
struct pf_ruleset *rs;
struct pf_rule *r; /* XXX: + match bit */
struct pf_anchor *child;
};
/*
* XXX: We rely on malloc(9) returning pointer aligned addresses.
*/
#define PF_ANCHORSTACK_MATCH 0x00000001
#define PF_ANCHORSTACK_MASK (PF_ANCHORSTACK_MATCH)
#define PF_ANCHOR_MATCH(f) ((uintptr_t)(f)->r & PF_ANCHORSTACK_MATCH)
#define PF_ANCHOR_RULE(f) (struct pf_rule *) \
((uintptr_t)(f)->r & ~PF_ANCHORSTACK_MASK)
#define PF_ANCHOR_SET_MATCH(f) do { (f)->r = (void *) \
((uintptr_t)(f)->r | PF_ANCHORSTACK_MATCH); \
} while (0)
void
pf_step_into_anchor(struct pf_anchor_stackframe *stack, int *depth,
struct pf_ruleset **rs, int n, struct pf_rule **r, struct pf_rule **a,
int *match)
{
struct pf_anchor_stackframe *f;
PF_RULES_RASSERT();
if (match)
*match = 0;
if (*depth >= PF_ANCHOR_STACKSIZE) {
printf("%s: anchor stack overflow on %s\n",
__func__, (*r)->anchor->name);
*r = TAILQ_NEXT(*r, entries);
return;
} else if (*depth == 0 && a != NULL)
*a = *r;
f = stack + (*depth)++;
f->rs = *rs;
f->r = *r;
if ((*r)->anchor_wildcard) {
struct pf_anchor_node *parent = &(*r)->anchor->children;
if ((f->child = RB_MIN(pf_anchor_node, parent)) == NULL) {
*r = NULL;
return;
}
*rs = &f->child->ruleset;
} else {
f->child = NULL;
*rs = &(*r)->anchor->ruleset;
}
*r = TAILQ_FIRST((*rs)->rules[n].active.ptr);
}
int
pf_step_out_of_anchor(struct pf_anchor_stackframe *stack, int *depth,
struct pf_ruleset **rs, int n, struct pf_rule **r, struct pf_rule **a,
int *match)
{
struct pf_anchor_stackframe *f;
struct pf_rule *fr;
int quick = 0;
PF_RULES_RASSERT();
do {
if (*depth <= 0)
break;
f = stack + *depth - 1;
fr = PF_ANCHOR_RULE(f);
if (f->child != NULL) {
struct pf_anchor_node *parent;
/*
* This block traverses through
* a wildcard anchor.
*/
parent = &fr->anchor->children;
if (match != NULL && *match) {
/*
* If any of "*" matched, then
* "foo/ *" matched, mark frame
* appropriately.
*/
PF_ANCHOR_SET_MATCH(f);
*match = 0;
}
f->child = RB_NEXT(pf_anchor_node, 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 (PF_ANCHOR_MATCH(f) || (match != NULL && *match))
quick = fr->quick;
*r = TAILQ_NEXT(fr, 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
pf_socket_lookup(int direction, struct pf_pdesc *pd, struct mbuf *m)
{
struct pf_addr *saddr, *daddr;
u_int16_t sport, dport;
struct inpcbinfo *pi;
struct inpcb *inp;
pd->lookup.uid = UID_MAX;
pd->lookup.gid = GID_MAX;
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;
pi = &V_tcbinfo;
break;
case IPPROTO_UDP:
if (pd->hdr.udp == NULL)
return (-1);
sport = pd->hdr.udp->uh_sport;
dport = pd->hdr.udp->uh_dport;
pi = &V_udbinfo;
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:
inp = in_pcblookup_mbuf(pi, saddr->v4, sport, daddr->v4,
dport, INPLOOKUP_RLOCKPCB, NULL, m);
if (inp == NULL) {
inp = in_pcblookup_mbuf(pi, saddr->v4, sport,
daddr->v4, dport, INPLOOKUP_WILDCARD |
INPLOOKUP_RLOCKPCB, NULL, m);
if (inp == NULL)
return (-1);
}
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
inp = in6_pcblookup_mbuf(pi, &saddr->v6, sport, &daddr->v6,
dport, INPLOOKUP_RLOCKPCB, NULL, m);
if (inp == NULL) {
inp = in6_pcblookup_mbuf(pi, &saddr->v6, sport,
&daddr->v6, dport, INPLOOKUP_WILDCARD |
INPLOOKUP_RLOCKPCB, NULL, m);
if (inp == NULL)
return (-1);
}
break;
#endif /* INET6 */
default:
return (-1);
}
INP_RLOCK_ASSERT(inp);
pd->lookup.uid = inp->inp_cred->cr_uid;
pd->lookup.gid = inp->inp_cred->cr_groups[0];
INP_RUNLOCK(inp);
return (1);
}
static 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);
}
static 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;
u_int16_t mss = V_tcp_mssdflt;
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);
}
static u_int16_t
pf_calc_mss(struct pf_addr *addr, sa_family_t af, int rtableid, 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;
int hlen = 0;
u_int16_t mss = V_tcp_mssdflt;
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;
in_rtalloc_ign(&ro, 0, rtableid);
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;
in6_rtalloc_ign(&ro6, 0, rtableid);
rt = ro6.ro_rt;
break;
#endif /* INET6 */
}
if (rt && rt->rt_ifp) {
mss = rt->rt_ifp->if_mtu - hlen - sizeof(struct tcphdr);
mss = max(V_tcp_mssdflt, mss);
RTFREE(rt);
}
mss = min(mss, offer);
mss = max(mss, 64); /* sanity - at least max opt space */
return (mss);
}
static 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 */
}
}
static u_int32_t
pf_tcp_iss(struct pf_pdesc *pd)
{
MD5_CTX ctx;
u_int32_t digest[4];
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;
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);
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
}
static int
pf_test_rule(struct pf_rule **rm, struct pf_state **sm, int direction,
struct pfi_kif *kif, struct mbuf *m, int off, struct pf_pdesc *pd,
struct pf_rule **am, struct pf_ruleset **rsm, struct inpcb *inp)
{
struct pf_rule *nr = NULL;
struct pf_addr * const saddr = pd->src;
struct pf_addr * const 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 *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;
u_int16_t sport = 0, dport = 0;
u_int16_t bproto_sum = 0, bip_sum = 0;
u_int8_t icmptype = 0, icmpcode = 0;
struct pf_anchor_stackframe anchor_stack[PF_ANCHOR_STACKSIZE];
PF_RULES_RASSERT();
if (inp != NULL) {
INP_LOCK_ASSERT(inp);
pd->lookup.uid = inp->inp_cred->cr_uid;
pd->lookup.gid = inp->inp_cred->cr_groups[0];
pd->lookup.done = 1;
}
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, &sk,
&nk, saddr, daddr, sport, dport, anchor_stack)) != NULL) {
KASSERT(sk != NULL, ("%s: null sk", __func__));
KASSERT(nk != NULL, ("%s: null nk", __func__));
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, M_GETFIB(m)))
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, M_GETFIB(m)))
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 =
pf_socket_lookup(direction, pd, m), 1)) &&
!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 =
pf_socket_lookup(direction, pd, m), 1)) &&
!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 &&
r->prob <= arc4random())
r = TAILQ_NEXT(r, entries);
else if (r->match_tag && !pf_match_tag(m, r, &tag,
pd->pf_mtag ? pd->pf_mtag->tag : 0))
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(anchor_stack, &asd,
&ruleset, PF_RULESET_FILTER, &r, &a,
&match);
}
if (r == NULL && pf_step_out_of_anchor(anchor_stack, &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, m, af, direction, reason, r->log ? r : nr, a,
ruleset, pd, 1);
}
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++;
pf_send_tcp(m, r, af, pd->dst,
pd->src, th->th_dport, th->th_sport,
ntohl(th->th_ack), ack, TH_RST|TH_ACK, 0, 0,
r->return_ttl, 1, 0, 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;
if (tag > 0 && pf_tag_packet(m, pd, tag)) {
REASON_SET(&reason, PFRES_MEMORY);
goto cleanup;
}
if (rtableid >= 0)
M_SETFIB(m, rtableid);
if (!state_icmp && (r->keep_state || nr != NULL ||
(pd->flags & PFDESC_TCP_NORM))) {
int action;
action = pf_create_state(r, nr, a, pd, nsn, nk, sk, m, off,
sport, dport, &rewrite, kif, sm, tag, bproto_sum, bip_sum,
hdrlen);
if (action != PF_PASS)
return (action);
} else {
if (sk != NULL)
uma_zfree(V_pf_state_key_z, sk);
if (nk != NULL)
uma_zfree(V_pf_state_key_z, nk);
}
/* copy back packet headers if we performed NAT operations */
if (rewrite)
m_copyback(m, off, hdrlen, pd->hdr.any);
if (*sm != NULL && !((*sm)->state_flags & PFSTATE_NOSYNC) &&
direction == PF_OUT &&
pfsync_defer_ptr != NULL && pfsync_defer_ptr(*sm, m))
/*
* 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.
*/
return (PF_DEFER);
return (PF_PASS);
cleanup:
if (sk != NULL)
uma_zfree(V_pf_state_key_z, sk);
if (nk != NULL)
uma_zfree(V_pf_state_key_z, nk);
return (PF_DROP);
}
static 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 *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;
u_int16_t mss = V_tcp_mssdflt;
u_short reason;
/* check maximums */
if (r->max_states &&
(counter_u64_fetch(r->states_cur) >= r->max_states)) {
V_pf_status.lcounters[LCNT_STATES]++;
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;
}
s = uma_zalloc(V_pf_state_z, M_NOWAIT | M_ZERO);
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;
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_uptime;
s->expire = time_uptime;
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);
uma_zfree(V_pf_state_z, s);
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);
uma_zfree(V_pf_state_z, s);
return (PF_DROP);
}
}
s->direction = pd->dir;
/*
* sk/nk could already been setup by pf_get_translation().
*/
if (nr == NULL) {
KASSERT((sk == NULL && nk == NULL), ("%s: nr %p sk %p, nk %p",
__func__, nr, sk, nk));
sk = pf_state_key_setup(pd, pd->src, pd->dst, sport, dport);
if (sk == NULL)
goto csfailed;
nk = sk;
} else
KASSERT((sk != NULL && nk != NULL), ("%s: nr %p sk %p, nk %p",
__func__, nr, sk, nk));
/* Swap sk/nk for PF_OUT. */
if (pf_state_insert(BOUND_IFACE(r, kif),
(pd->dir == PF_IN) ? sk : nk,
(pd->dir == PF_IN) ? nk : sk, 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);
uma_zfree(V_pf_state_z, s);
return (PF_DROP);
} else
*sm = s;
pf_set_rt_ifp(s, pd->src); /* needs s->state_key set */
if (tag > 0)
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 */
int rtid = M_GETFIB(m);
mss = pf_get_mss(m, off, th->th_off, pd->af);
mss = pf_calc_mss(pd->src, pd->af, rtid, mss);
mss = pf_calc_mss(pd->dst, pd->af, rtid, mss);
s->src.mss = mss;
pf_send_tcp(NULL, r, pd->af, pd->dst, pd->src, th->th_dport,
th->th_sport, s->src.seqhi, ntohl(th->th_seq) + 1,
TH_SYN|TH_ACK, 0, s->src.mss, 0, 1, 0, NULL);
REASON_SET(&reason, PFRES_SYNPROXY);
return (PF_SYNPROXY_DROP);
}
return (PF_PASS);
csfailed:
if (sk != NULL)
uma_zfree(V_pf_state_key_z, sk);
if (nk != NULL)
uma_zfree(V_pf_state_key_z, nk);
if (sn != NULL && sn->states == 0 && sn->expire == 0) {
pf_unlink_src_node(sn);
pf_free_src_node(sn);
}
if (nsn != sn && nsn != NULL && nsn->states == 0 && nsn->expire == 0) {
pf_unlink_src_node(nsn);
pf_free_src_node(nsn);
}
return (PF_DROP);
}
static 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;
struct pf_anchor_stackframe anchor_stack[PF_ANCHOR_STACKSIZE];
PF_RULES_RASSERT();
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, M_GETFIB(m)))
r = r->skip[PF_SKIP_SRC_ADDR].ptr;
else if (PF_MISMATCHAW(&r->dst.addr, pd->dst, af,
r->dst.neg, NULL, M_GETFIB(m)))
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);
else if (r->match_tag && !pf_match_tag(m, r, &tag,
pd->pf_mtag ? pd->pf_mtag->tag : 0))
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(anchor_stack, &asd,
&ruleset, PF_RULESET_FILTER, &r, &a,
&match);
}
if (r == NULL && pf_step_out_of_anchor(anchor_stack, &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, m, af, direction, reason, r, a, ruleset, pd,
1);
if (r->action != PF_PASS)
return (PF_DROP);
if (tag > 0 && pf_tag_packet(m, pd, tag)) {
REASON_SET(&reason, PFRES_MEMORY);
return (PF_DROP);
}
return (PF_PASS);
}
static 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_uptime;
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.
*/
if (V_pf_status.debug >= PF_DEBUG_MISC) {
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,
pd->p_len, ackskew, (unsigned long long)(*state)->packets[0],
(unsigned long long)(*state)->packets[1],
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))
pf_send_tcp(NULL, (*state)->rule.ptr, pd->af,
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,
kif->pfik_ifp);
src->seqlo = 0;
src->seqhi = 1;
src->max_win = 1;
} else if (V_pf_status.debug >= PF_DEBUG_MISC) {
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,
(unsigned long long)(*state)->packets[0],
(unsigned long long)(*state)->packets[1],
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);
}
static 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_uptime;
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);
}
static 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;
bzero(&key, sizeof(key));
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;
}
STATE_LOOKUP(kif, &key, direction, *state, pd);
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);
}
pf_send_tcp(NULL, (*state)->rule.ptr, pd->af, pd->dst,
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);
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());
pf_send_tcp(NULL, (*state)->rule.ptr, pd->af,
&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);
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);
pf_send_tcp(NULL, (*state)->rule.ptr, pd->af, pd->dst,
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);
pf_send_tcp(NULL, (*state)->rule.ptr, pd->af,
&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);
(*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) {
if (V_pf_status.debug >= PF_DEBUG_MISC) {
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, PF_ENTER_LOCKED);
*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)
m_copyback(m, off, sizeof(*th), (caddr_t)th);
return (PF_PASS);
}
static 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;
bzero(&key, sizeof(key));
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;
}
STATE_LOOKUP(kif, &key, direction, *state, pd);
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_uptime;
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);
m_copyback(m, off, sizeof(*uh), (caddr_t)uh);
}
return (PF_PASS);
}
static 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;
u_int16_t icmpid = 0, *icmpsum;
u_int8_t icmptype;
int state_icmp = 0;
struct pf_state_key_cmp key;
bzero(&key, sizeof(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);
}
STATE_LOOKUP(kif, &key, direction, *state, pd);
(*state)->expire = time_uptime;
(*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,
(caddr_t )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),
(caddr_t )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;
bzero(&pd2, sizeof pd2);
#ifdef INET
struct ip h2;
#endif /* INET */
#ifdef INET6
struct ip6_hdr h2_6;
int terminal = 0;
#endif /* INET6 */
int ipoff2 = 0;
int off2 = 0;
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;
STATE_LOOKUP(kif, &key, direction, *state, pd);
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)))) {
if (V_pf_status.debug >= PF_DEBUG_MISC) {
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 {
if (V_pf_status.debug >= PF_DEBUG_MISC) {
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,
(caddr_t )pd->hdr.icmp);
m_copyback(m, ipoff2, sizeof(h2),
(caddr_t )&h2);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
m_copyback(m, off,
sizeof(struct icmp6_hdr),
(caddr_t )pd->hdr.icmp6);
m_copyback(m, ipoff2, sizeof(h2_6),
(caddr_t )&h2_6);
break;
#endif /* INET6 */
}
m_copyback(m, off2, 8, (caddr_t)&th);
}
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;
STATE_LOOKUP(kif, &key, direction, *state, pd);
/* 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,
(caddr_t )pd->hdr.icmp);
m_copyback(m, ipoff2, sizeof(h2), (caddr_t)&h2);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
m_copyback(m, off,
sizeof(struct icmp6_hdr),
(caddr_t )pd->hdr.icmp6);
m_copyback(m, ipoff2, sizeof(h2_6),
(caddr_t )&h2_6);
break;
#endif /* INET6 */
}
m_copyback(m, off2, sizeof(uh), (caddr_t)&uh);
}
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;
STATE_LOOKUP(kif, &key, direction, *state, pd);
/* 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);
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);
}
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;
STATE_LOOKUP(kif, &key, direction, *state, pd);
/* 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);
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);
}
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;
STATE_LOOKUP(kif, &key, direction, *state, pd);
/* 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:
m_copyback(m, off, ICMP_MINLEN,
(caddr_t)pd->hdr.icmp);
m_copyback(m, ipoff2, sizeof(h2), (caddr_t)&h2);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
m_copyback(m, off,
sizeof(struct icmp6_hdr),
(caddr_t )pd->hdr.icmp6);
m_copyback(m, ipoff2, sizeof(h2_6),
(caddr_t )&h2_6);
break;
#endif /* INET6 */
}
}
return (PF_PASS);
break;
}
}
}
}
static 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;
bzero(&key, sizeof(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;
}
STATE_LOOKUP(kif, &key, direction, *state, pd);
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_uptime;
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];
KASSERT(nk, ("%s: nk is null", __func__));
KASSERT(pd, ("%s: pd is null", __func__));
KASSERT(pd->src, ("%s: pd->src is null", __func__));
KASSERT(pd->dst, ("%s: pd->dst is null", __func__));
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,
int rtableid)
{
#ifdef RADIX_MPATH
struct radix_node_head *rnh;
#endif
struct sockaddr_in *dst;
int ret = 1;
int check_mpath;
#ifdef INET6
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 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
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:
/*
* 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;
break;
#endif /* INET6 */
default:
return (0);
}
/* Skip checks for ipsec interfaces */
if (kif != NULL && kif->pfik_ifp->if_type == IFT_ENC)
goto out;
switch (af) {
#ifdef INET6
case AF_INET6:
in6_rtalloc_ign(&ro, 0, rtableid);
break;
#endif
#ifdef INET
case AF_INET:
in_rtalloc_ign((struct route *)&ro, 0, rtableid);
break;
#endif
default:
rtalloc_ign((struct route *)&ro, 0); /* No/default FIB. */
break;
}
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;
ifp = rt->rt_ifp;
if (kif->pfik_ifp == ifp)
ret = 1;
#ifdef RADIX_MPATH
rn = rn_mpath_next(rn);
#endif
} while (check_mpath == 1 && rn != NULL && ret == 0);
} else
ret = 0;
out:
if (ro.ro_rt != NULL)
RTFREE(ro.ro_rt);
return (ret);
}
#ifdef INET
static 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 sockaddr_in dst;
struct ip *ip;
struct ifnet *ifp = NULL;
struct pf_addr naddr;
struct pf_src_node *sn = NULL;
int error = 0;
uint16_t ip_len, ip_off;
KASSERT(m && *m && r && oifp, ("%s: invalid parameters", __func__));
KASSERT(dir == PF_IN || dir == PF_OUT, ("%s: invalid direction",
__func__));
if ((pd->pf_mtag == NULL &&
((pd->pf_mtag = pf_get_mtag(*m)) == NULL)) ||
pd->pf_mtag->routed++ > 3) {
m0 = *m;
*m = NULL;
goto bad_locked;
}
if (r->rt == PF_DUPTO) {
if ((m0 = m_dup(*m, M_NOWAIT)) == NULL) {
if (s)
PF_STATE_UNLOCK(s);
return;
}
} else {
if ((r->rt == PF_REPLYTO) == (r->direction == dir)) {
if (s)
PF_STATE_UNLOCK(s);
return;
}
m0 = *m;
}
ip = mtod(m0, struct ip *);
bzero(&dst, sizeof(dst));
dst.sin_family = AF_INET;
dst.sin_len = sizeof(dst);
dst.sin_addr = ip->ip_dst;
if (r->rt == PF_FASTROUTE) {
struct rtentry *rt;
if (s)
PF_STATE_UNLOCK(s);
rt = rtalloc1_fib(sintosa(&dst), 0, 0, M_GETFIB(m0));
if (rt == NULL) {
KMOD_IPSTAT_INC(ips_noroute);
error = EHOSTUNREACH;
goto bad;
}
ifp = rt->rt_ifp;
counter_u64_add(rt->rt_pksent, 1);
if (rt->rt_flags & RTF_GATEWAY)
bcopy(satosin(rt->rt_gateway), &dst, sizeof(dst));
RTFREE_LOCKED(rt);
} else {
if (TAILQ_EMPTY(&r->rpool.list)) {
DPFPRINTF(PF_DEBUG_URGENT,
("%s: TAILQ_EMPTY(&r->rpool.list)\n", __func__));
goto bad_locked;
}
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;
PF_STATE_UNLOCK(s);
}
}
if (ifp == NULL)
goto bad;
if (oifp != ifp) {
if (pf_test(PF_OUT, ifp, &m0, NULL) != PF_PASS)
goto bad;
else if (m0 == NULL)
goto done;
if (m0->m_len < sizeof(struct ip)) {
DPFPRINTF(PF_DEBUG_URGENT,
("%s: m0->m_len < sizeof(struct ip)\n", __func__));
goto bad;
}
ip = mtod(m0, struct ip *);
}
if (ifp->if_flags & IFF_LOOPBACK)
m0->m_flags |= M_SKIP_FIREWALL;
ip_len = ntohs(ip->ip_len);
ip_off = ntohs(ip->ip_off);
/* Copied from FreeBSD 10.0-CURRENT ip_output. */
m0->m_pkthdr.csum_flags |= CSUM_IP;
if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA & ~ifp->if_hwassist) {
in_delayed_cksum(m0);
m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
}
#ifdef SCTP
if (m0->m_pkthdr.csum_flags & CSUM_SCTP & ~ifp->if_hwassist) {
sctp_delayed_cksum(m, (uint32_t)(ip->ip_hl << 2));
m0->m_pkthdr.csum_flags &= ~CSUM_SCTP;
}
#endif
/*
* If small enough for interface, or the interface will take
* care of the fragmentation for us, we can just send directly.
*/
if (ip_len <= ifp->if_mtu ||
(m0->m_pkthdr.csum_flags & ifp->if_hwassist & CSUM_TSO) != 0 ||
((ip_off & IP_DF) == 0 && (ifp->if_hwassist & CSUM_FRAGMENT))) {
ip->ip_sum = 0;
if (m0->m_pkthdr.csum_flags & CSUM_IP & ~ifp->if_hwassist) {
ip->ip_sum = in_cksum(m0, ip->ip_hl << 2);
m0->m_pkthdr.csum_flags &= ~CSUM_IP;
}
m_clrprotoflags(m0); /* Avoid confusing lower layers. */
error = (*ifp->if_output)(ifp, m0, sintosa(&dst), NULL);
goto done;
}
/* Balk when DF bit is set or the interface didn't support TSO. */
if ((ip_off & IP_DF) || (m0->m_pkthdr.csum_flags & CSUM_TSO)) {
error = EMSGSIZE;
KMOD_IPSTAT_INC(ips_cantfrag);
if (r->rt != PF_DUPTO) {
icmp_error(m0, ICMP_UNREACH, ICMP_UNREACH_NEEDFRAG, 0,
ifp->if_mtu);
goto done;
} else
goto bad;
}
error = ip_fragment(ip, &m0, ifp->if_mtu, ifp->if_hwassist);
if (error)
goto bad;
for (; m0; m0 = m1) {
m1 = m0->m_nextpkt;
m0->m_nextpkt = NULL;
if (error == 0) {
m_clrprotoflags(m0);
error = (*ifp->if_output)(ifp, m0, sintosa(&dst), NULL);
} else
m_freem(m0);
}
if (error == 0)
KMOD_IPSTAT_INC(ips_fragmented);
done:
if (r->rt != PF_DUPTO)
*m = NULL;
return;
bad_locked:
if (s)
PF_STATE_UNLOCK(s);
bad:
m_freem(m0);
goto done;
}
#endif /* INET */
#ifdef INET6
static 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 sockaddr_in6 dst;
struct ip6_hdr *ip6;
struct ifnet *ifp = NULL;
struct pf_addr naddr;
struct pf_src_node *sn = NULL;
KASSERT(m && *m && r && oifp, ("%s: invalid parameters", __func__));
KASSERT(dir == PF_IN || dir == PF_OUT, ("%s: invalid direction",
__func__));
if ((pd->pf_mtag == NULL &&
((pd->pf_mtag = pf_get_mtag(*m)) == NULL)) ||
pd->pf_mtag->routed++ > 3) {
m0 = *m;
*m = NULL;
goto bad_locked;
}
if (r->rt == PF_DUPTO) {
if ((m0 = m_dup(*m, M_NOWAIT)) == NULL) {
if (s)
PF_STATE_UNLOCK(s);
return;
}
} else {
if ((r->rt == PF_REPLYTO) == (r->direction == dir)) {
if (s)
PF_STATE_UNLOCK(s);
return;
}
m0 = *m;
}
ip6 = mtod(m0, struct ip6_hdr *);
bzero(&dst, sizeof(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) {
if (s)
PF_STATE_UNLOCK(s);
m0->m_flags |= M_SKIP_FIREWALL;
ip6_output(m0, NULL, NULL, 0, NULL, NULL, NULL);
return;
}
if (TAILQ_EMPTY(&r->rpool.list)) {
DPFPRINTF(PF_DEBUG_URGENT,
("%s: TAILQ_EMPTY(&r->rpool.list)\n", __func__));
goto bad_locked;
}
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 (s)
PF_STATE_UNLOCK(s);
if (ifp == NULL)
goto bad;
if (oifp != ifp) {
if (pf_test6(PF_OUT, ifp, &m0, NULL) != PF_PASS)
goto bad;
else if (m0 == NULL)
goto done;
if (m0->m_len < sizeof(struct ip6_hdr)) {
DPFPRINTF(PF_DEBUG_URGENT,
("%s: m0->m_len < sizeof(struct ip6_hdr)\n",
__func__));
goto bad;
}
ip6 = mtod(m0, struct ip6_hdr *);
}
if (ifp->if_flags & IFF_LOOPBACK)
m0->m_flags |= M_SKIP_FIREWALL;
/*
* 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)
nd6_output(ifp, ifp, m0, &dst, NULL);
else {
in6_ifstat_inc(ifp, ifs6_in_toobig);
if (r->rt != PF_DUPTO)
icmp6_error(m0, ICMP6_PACKET_TOO_BIG, 0, ifp->if_mtu);
else
goto bad;
}
done:
if (r->rt != PF_DUPTO)
*m = NULL;
return;
bad_locked:
if (s)
PF_STATE_UNLOCK(s);
bad:
m_freem(m0);
goto done;
}
#endif /* INET6 */
/*
* FreeBSD supports cksum offloads for the following drivers.
* 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.
*/
static 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);
}
#ifdef INET
int
pf_test(int dir, struct ifnet *ifp, struct mbuf **m0, struct inpcb *inp)
{
struct pfi_kif *kif;
u_short action, reason = 0, log = 0;
struct mbuf *m = *m0;
struct ip *h = NULL;
struct m_tag *ipfwtag;
struct pf_rule *a = NULL, *r = &V_pf_default_rule, *tr, *nr;
struct pf_state *s = NULL;
struct pf_ruleset *ruleset = NULL;
struct pf_pdesc pd;
int off, dirndx, pqid = 0;
M_ASSERTPKTHDR(m);
if (!V_pf_status.running)
return (PF_PASS);
memset(&pd, 0, sizeof(pd));
kif = (struct pfi_kif *)ifp->if_pf_kif;
if (kif == NULL) {
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)
return (PF_PASS);
if (m->m_flags & M_SKIP_FIREWALL)
return (PF_PASS);
pd.pf_mtag = pf_find_mtag(m);
PF_RULES_RLOCK();
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) {
if (pd.pf_mtag == NULL &&
((pd.pf_mtag = pf_get_mtag(m)) == NULL)) {
action = PF_DROP;
goto done;
}
pd.pf_mtag->flags |= PF_PACKET_LOOPED;
m_tag_delete(m, ipfwtag);
}
if (pd.pf_mtag && pd.pf_mtag->flags & PF_FASTFWD_OURS_PRESENT) {
m->m_flags |= M_FASTFWD_OURS;
pd.pf_mtag->flags &= ~PF_FASTFWD_OURS_PRESENT;
}
} else if (pf_normalize_ip(m0, dir, kif, &reason, &pd) != PF_PASS) {
/* We do IP header normalization and packet reassembly here */
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(struct ip)) {
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);
/* 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 (pfsync_update_state_ptr != NULL)
pfsync_update_state_ptr(s);
r = s->rule.ptr;
a = s->anchor.ptr;
log = s->log;
} else if (s == NULL)
action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
&a, &ruleset, inp);
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 (pfsync_update_state_ptr != NULL)
pfsync_update_state_ptr(s);
r = s->rule.ptr;
a = s->anchor.ptr;
log = s->log;
} else if (s == NULL)
action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
&a, &ruleset, inp);
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 (pfsync_update_state_ptr != NULL)
pfsync_update_state_ptr(s);
r = s->rule.ptr;
a = s->anchor.ptr;
log = s->log;
} else if (s == NULL)
action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
&a, &ruleset, inp);
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 (pfsync_update_state_ptr != NULL)
pfsync_update_state_ptr(s);
r = s->rule.ptr;
a = s->anchor.ptr;
log = s->log;
} else if (s == NULL)
action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
&a, &ruleset, inp);
break;
}
done:
PF_RULES_RUNLOCK();
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 > 0 && pf_tag_packet(m, &pd, s->tag)) {
action = PF_DROP;
REASON_SET(&reason, PFRES_MEMORY);
}
if (r->rtableid >= 0)
M_SETFIB(m, r->rtableid);
#ifdef ALTQ
if (action == PF_PASS && r->qid) {
if (pd.pf_mtag == NULL &&
((pd.pf_mtag = pf_get_mtag(m)) == NULL)) {
action = PF_DROP;
REASON_SET(&reason, PFRES_MEMORY);
}
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;
}
#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)
m->m_flags |= M_SKIP_FIREWALL;
if (action == PF_PASS && r->divert.port && ip_divert_ptr != NULL &&
!PACKET_LOOPED(&pd)) {
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 =
ntohs(r->divert.port);
((struct ipfw_rule_ref *)(ipfwtag+1))->rulenum = dir;
if (s)
PF_STATE_UNLOCK(s);
m_tag_prepend(m, ipfwtag);
if (m->m_flags & M_FASTFWD_OURS) {
if (pd.pf_mtag == NULL &&
((pd.pf_mtag = pf_get_mtag(m)) == NULL)) {
action = PF_DROP;
REASON_SET(&reason, PFRES_MEMORY);
log = 1;
DPFPRINTF(PF_DEBUG_MISC,
("pf: failed to allocate tag\n"));
}
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"));
}
}
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, m, AF_INET, dir, reason, lr, a, ruleset, &pd,
(s == NULL));
}
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;
if (nr != NULL && r == &V_pf_default_rule)
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() returns unlocked. */
if (r->rt) {
pf_route(m0, r, dir, kif->pfik_ifp, s, &pd);
return (action);
}
break;
}
if (s)
PF_STATE_UNLOCK(s);
return (action);
}
#endif /* INET */
#ifdef INET6
int
pf_test6(int dir, struct ifnet *ifp, struct mbuf **m0, struct inpcb *inp)
{
struct pfi_kif *kif;
u_short action, reason = 0, log = 0;
struct mbuf *m = *m0, *n = NULL;
struct ip6_hdr *h = NULL;
struct pf_rule *a = NULL, *r = &V_pf_default_rule, *tr, *nr;
struct pf_state *s = NULL;
struct pf_ruleset *ruleset = NULL;
struct pf_pdesc pd;
int off, terminal = 0, dirndx, rh_cnt = 0;
M_ASSERTPKTHDR(m);
if (!V_pf_status.running)
return (PF_PASS);
memset(&pd, 0, sizeof(pd));
pd.pf_mtag = pf_find_mtag(m);
if (pd.pf_mtag && pd.pf_mtag->flags & PF_TAG_GENERATED)
return (PF_PASS);
kif = (struct pfi_kif *)ifp->if_pf_kif;
if (kif == NULL) {
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)
return (PF_PASS);
PF_RULES_RLOCK();
/* 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);
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 (pfsync_update_state_ptr != NULL)
pfsync_update_state_ptr(s);
r = s->rule.ptr;
a = s->anchor.ptr;
log = s->log;
} else if (s == NULL)
action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
&a, &ruleset, inp);
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 (pfsync_update_state_ptr != NULL)
pfsync_update_state_ptr(s);
r = s->rule.ptr;
a = s->anchor.ptr;
log = s->log;
} else if (s == NULL)
action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
&a, &ruleset, inp);
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 (pfsync_update_state_ptr != NULL)
pfsync_update_state_ptr(s);
r = s->rule.ptr;
a = s->anchor.ptr;
log = s->log;
} else if (s == NULL)
action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
&a, &ruleset, inp);
break;
}
default:
action = pf_test_state_other(&s, dir, kif, m, &pd);
if (action == PF_PASS) {
if (pfsync_update_state_ptr != NULL)
pfsync_update_state_ptr(s);
r = s->rule.ptr;
a = s->anchor.ptr;
log = s->log;
} else if (s == NULL)
action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
&a, &ruleset, inp);
break;
}
done:
PF_RULES_RUNLOCK();
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 > 0 && pf_tag_packet(m, &pd, s->tag)) {
action = PF_DROP;
REASON_SET(&reason, PFRES_MEMORY);
}
if (r->rtableid >= 0)
M_SETFIB(m, r->rtableid);
#ifdef ALTQ
if (action == PF_PASS && r->qid) {
if (pd.pf_mtag == NULL &&
((pd.pf_mtag = pf_get_mtag(m)) == NULL)) {
action = PF_DROP;
REASON_SET(&reason, PFRES_MEMORY);
}
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;
}
#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))
m->m_flags |= M_SKIP_FIREWALL;
/* XXX: Anybody working on it?! */
if (r->divert.port)
printf("pf: divert(9) is not supported for IPv6\n");
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, m, AF_INET6, dir, reason, lr, a, ruleset,
&pd, (s == NULL));
}
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;
if (nr != NULL && r == &V_pf_default_rule)
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() returns unlocked. */
if (r->rt) {
pf_route6(m0, r, dir, kif->pfik_ifp, s, &pd);
return (action);
}
break;
}
if (s)
PF_STATE_UNLOCK(s);
return (action);
}
#endif /* INET6 */
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