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75bf2db380
freebsd-nq/sys/netpfil/pf/pf_lb.c
Gleb Smirnoff 75bf2db380 Move new pf includes to the pf directory. The pfvar.h remain 
in net, to avoid compatibility breakage for no sake.

The future plan is to split most of non-kernel parts of
pfvar.h into pf.h, and then make pfvar.h a kernel only
include breaking compatibility.

Discussed with:		bz
2013-10-27 16:25:57 +00:00

672 lines
19 KiB
C
Raw Blame History

/*-
* Copyright (c) 2001 Daniel Hartmeier
* Copyright (c) 2002 - 2008 Henning Brauer
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* Effort sponsored in part by the Defense Advanced Research Projects
* Agency (DARPA) and Air Force Research Laboratory, Air Force
* Materiel Command, USAF, under agreement number F30602-01-2-0537.
*
* $OpenBSD: pf_lb.c,v 1.2 2009/02/12 02:13:15 sthen Exp $
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_pf.h"
#include "opt_inet.h"
#include "opt_inet6.h"
#include <sys/param.h>
#include <sys/lock.h>
#include <sys/mbuf.h>
#include <sys/rwlock.h>
#include <sys/socket.h>
#include <sys/sysctl.h>
#include <net/if.h>
#include <net/vnet.h>
#include <net/pfvar.h>
#include <net/if_pflog.h>
#define DPFPRINTF(n, x) if (V_pf_status.debug >= (n)) printf x
static void pf_hash(struct pf_addr *, struct pf_addr *,
struct pf_poolhashkey *, sa_family_t);
static struct pf_rule *pf_match_translation(struct pf_pdesc *, struct mbuf *,
int, int, struct pfi_kif *,
struct pf_addr *, u_int16_t, struct pf_addr *,
uint16_t, int, struct pf_anchor_stackframe *);
static int pf_get_sport(sa_family_t, uint8_t, struct pf_rule *,
struct pf_addr *, uint16_t, struct pf_addr *, uint16_t, struct pf_addr *,
uint16_t *, uint16_t, uint16_t, struct pf_src_node **);
#define mix(a,b,c) \
do { \
a -= b; a -= c; a ^= (c >> 13); \
b -= c; b -= a; b ^= (a << 8); \
c -= a; c -= b; c ^= (b >> 13); \
a -= b; a -= c; a ^= (c >> 12); \
b -= c; b -= a; b ^= (a << 16); \
c -= a; c -= b; c ^= (b >> 5); \
a -= b; a -= c; a ^= (c >> 3); \
b -= c; b -= a; b ^= (a << 10); \
c -= a; c -= b; c ^= (b >> 15); \
} while (0)
/*
* hash function based on bridge_hash in if_bridge.c
*/
static void
pf_hash(struct pf_addr *inaddr, struct pf_addr *hash,
struct pf_poolhashkey *key, sa_family_t af)
{
u_int32_t a = 0x9e3779b9, b = 0x9e3779b9, c = key->key32[0];
switch (af) {
#ifdef INET
case AF_INET:
a += inaddr->addr32[0];
b += key->key32[1];
mix(a, b, c);
hash->addr32[0] = c + key->key32[2];
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
a += inaddr->addr32[0];
b += inaddr->addr32[2];
mix(a, b, c);
hash->addr32[0] = c;
a += inaddr->addr32[1];
b += inaddr->addr32[3];
c += key->key32[1];
mix(a, b, c);
hash->addr32[1] = c;
a += inaddr->addr32[2];
b += inaddr->addr32[1];
c += key->key32[2];
mix(a, b, c);
hash->addr32[2] = c;
a += inaddr->addr32[3];
b += inaddr->addr32[0];
c += key->key32[3];
mix(a, b, c);
hash->addr32[3] = c;
break;
#endif /* INET6 */
}
}
static struct pf_rule *
pf_match_translation(struct pf_pdesc *pd, struct mbuf *m, int off,
int direction, struct pfi_kif *kif, struct pf_addr *saddr, u_int16_t sport,
struct pf_addr *daddr, uint16_t dport, int rs_num,
struct pf_anchor_stackframe *anchor_stack)
{
struct pf_rule *r, *rm = NULL;
struct pf_ruleset *ruleset = NULL;
int tag = -1;
int rtableid = -1;
int asd = 0;
r = TAILQ_FIRST(pf_main_ruleset.rules[rs_num].active.ptr);
while (r && rm == NULL) {
struct pf_rule_addr *src = NULL, *dst = NULL;
struct pf_addr_wrap *xdst = NULL;
if (r->action == PF_BINAT && direction == PF_IN) {
src = &r->dst;
if (r->rpool.cur != NULL)
xdst = &r->rpool.cur->addr;
} else {
src = &r->src;
dst = &r->dst;
}
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 != pd->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(&src->addr, saddr, pd->af,
src->neg, kif, M_GETFIB(m)))
r = r->skip[src == &r->src ? PF_SKIP_SRC_ADDR :
PF_SKIP_DST_ADDR].ptr;
else if (src->port_op && !pf_match_port(src->port_op,
src->port[0], src->port[1], sport))
r = r->skip[src == &r->src ? PF_SKIP_SRC_PORT :
PF_SKIP_DST_PORT].ptr;
else if (dst != NULL &&
PF_MISMATCHAW(&dst->addr, daddr, pd->af, dst->neg, NULL,
M_GETFIB(m)))
r = r->skip[PF_SKIP_DST_ADDR].ptr;
else if (xdst != NULL && PF_MISMATCHAW(xdst, daddr, pd->af,
0, NULL, M_GETFIB(m)))
r = TAILQ_NEXT(r, entries);
else if (dst != NULL && dst->port_op &&
!pf_match_port(dst->port_op, dst->port[0],
dst->port[1], dport))
r = r->skip[PF_SKIP_DST_PORT].ptr;
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, pd->hdr.tcp), 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) {
rm = r;
} else
pf_step_into_anchor(anchor_stack, &asd,
&ruleset, rs_num, &r, NULL, NULL);
}
if (r == NULL)
pf_step_out_of_anchor(anchor_stack, &asd, &ruleset,
rs_num, &r, NULL, NULL);
}
if (tag > 0 && pf_tag_packet(m, pd, tag))
return (NULL);
if (rtableid >= 0)
M_SETFIB(m, rtableid);
if (rm != NULL && (rm->action == PF_NONAT ||
rm->action == PF_NORDR || rm->action == PF_NOBINAT))
return (NULL);
return (rm);
}
static int
pf_get_sport(sa_family_t af, u_int8_t proto, struct pf_rule *r,
struct pf_addr *saddr, uint16_t sport, struct pf_addr *daddr,
uint16_t dport, struct pf_addr *naddr, uint16_t *nport, uint16_t low,
uint16_t high, struct pf_src_node **sn)
{
struct pf_state_key_cmp key;
struct pf_addr init_addr;
uint16_t cut;
bzero(&init_addr, sizeof(init_addr));
if (pf_map_addr(af, r, saddr, naddr, &init_addr, sn))
return (1);
if (proto == IPPROTO_ICMP) {
low = 1;
high = 65535;
}
bzero(&key, sizeof(key));
key.af = af;
key.proto = proto;
key.port[0] = dport;
PF_ACPY(&key.addr[0], daddr, key.af);
do {
PF_ACPY(&key.addr[1], naddr, key.af);
/*
* port search; start random, step;
* similar 2 portloop in in_pcbbind
*/
if (!(proto == IPPROTO_TCP || proto == IPPROTO_UDP ||
proto == IPPROTO_ICMP) || (low == 0 && high == 0)) {
/*
* XXX bug: icmp states don't use the id on both sides.
* (traceroute -I through nat)
*/
key.port[1] = sport;
if (pf_find_state_all(&key, PF_IN, NULL) == NULL) {
*nport = sport;
return (0);
}
} else if (low == high) {
key.port[1] = htons(low);
if (pf_find_state_all(&key, PF_IN, NULL) == NULL) {
*nport = htons(low);
return (0);
}
} else {
uint16_t tmp;
if (low > high) {
tmp = low;
low = high;
high = tmp;
}
/* low < high */
cut = htonl(arc4random()) % (1 + high - low) + low;
/* low <= cut <= high */
for (tmp = cut; tmp <= high; ++(tmp)) {
key.port[1] = htons(tmp);
if (pf_find_state_all(&key, PF_IN, NULL) ==
NULL) {
*nport = htons(tmp);
return (0);
}
}
for (tmp = cut - 1; tmp >= low; --(tmp)) {
key.port[1] = htons(tmp);
if (pf_find_state_all(&key, PF_IN, NULL) ==
NULL) {
*nport = htons(tmp);
return (0);
}
}
}
switch (r->rpool.opts & PF_POOL_TYPEMASK) {
case PF_POOL_RANDOM:
case PF_POOL_ROUNDROBIN:
if (pf_map_addr(af, r, saddr, naddr, &init_addr, sn))
return (1);
break;
case PF_POOL_NONE:
case PF_POOL_SRCHASH:
case PF_POOL_BITMASK:
default:
return (1);
}
} while (! PF_AEQ(&init_addr, naddr, af) );
return (1); /* none available */
}
int
pf_map_addr(sa_family_t af, struct pf_rule *r, struct pf_addr *saddr,
struct pf_addr *naddr, struct pf_addr *init_addr, struct pf_src_node **sn)
{
struct pf_pool *rpool = &r->rpool;
struct pf_addr *raddr = NULL, *rmask = NULL;
if (*sn == NULL && r->rpool.opts & PF_POOL_STICKYADDR &&
(r->rpool.opts & PF_POOL_TYPEMASK) != PF_POOL_NONE) {
*sn = pf_find_src_node(saddr, r, af, 0);
if (*sn != NULL && !PF_AZERO(&(*sn)->raddr, af)) {
PF_ACPY(naddr, &(*sn)->raddr, af);
if (V_pf_status.debug >= PF_DEBUG_MISC) {
printf("pf_map_addr: src tracking maps ");
pf_print_host(saddr, 0, af);
printf(" to ");
pf_print_host(naddr, 0, af);
printf("\n");
}
return (0);
}
}
if (rpool->cur->addr.type == PF_ADDR_NOROUTE)
return (1);
if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) {
switch (af) {
#ifdef INET
case AF_INET:
if (rpool->cur->addr.p.dyn->pfid_acnt4 < 1 &&
(rpool->opts & PF_POOL_TYPEMASK) !=
PF_POOL_ROUNDROBIN)
return (1);
raddr = &rpool->cur->addr.p.dyn->pfid_addr4;
rmask = &rpool->cur->addr.p.dyn->pfid_mask4;
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
if (rpool->cur->addr.p.dyn->pfid_acnt6 < 1 &&
(rpool->opts & PF_POOL_TYPEMASK) !=
PF_POOL_ROUNDROBIN)
return (1);
raddr = &rpool->cur->addr.p.dyn->pfid_addr6;
rmask = &rpool->cur->addr.p.dyn->pfid_mask6;
break;
#endif /* INET6 */
}
} else if (rpool->cur->addr.type == PF_ADDR_TABLE) {
if ((rpool->opts & PF_POOL_TYPEMASK) != PF_POOL_ROUNDROBIN)
return (1); /* unsupported */
} else {
raddr = &rpool->cur->addr.v.a.addr;
rmask = &rpool->cur->addr.v.a.mask;
}
switch (rpool->opts & PF_POOL_TYPEMASK) {
case PF_POOL_NONE:
PF_ACPY(naddr, raddr, af);
break;
case PF_POOL_BITMASK:
PF_POOLMASK(naddr, raddr, rmask, saddr, af);
break;
case PF_POOL_RANDOM:
if (init_addr != NULL && PF_AZERO(init_addr, af)) {
switch (af) {
#ifdef INET
case AF_INET:
rpool->counter.addr32[0] = htonl(arc4random());
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
if (rmask->addr32[3] != 0xffffffff)
rpool->counter.addr32[3] =
htonl(arc4random());
else
break;
if (rmask->addr32[2] != 0xffffffff)
rpool->counter.addr32[2] =
htonl(arc4random());
else
break;
if (rmask->addr32[1] != 0xffffffff)
rpool->counter.addr32[1] =
htonl(arc4random());
else
break;
if (rmask->addr32[0] != 0xffffffff)
rpool->counter.addr32[0] =
htonl(arc4random());
break;
#endif /* INET6 */
}
PF_POOLMASK(naddr, raddr, rmask, &rpool->counter, af);
PF_ACPY(init_addr, naddr, af);
} else {
PF_AINC(&rpool->counter, af);
PF_POOLMASK(naddr, raddr, rmask, &rpool->counter, af);
}
break;
case PF_POOL_SRCHASH:
{
unsigned char hash[16];
pf_hash(saddr, (struct pf_addr *)&hash, &rpool->key, af);
PF_POOLMASK(naddr, raddr, rmask, (struct pf_addr *)&hash, af);
break;
}
case PF_POOL_ROUNDROBIN:
{
struct pf_pooladdr *acur = rpool->cur;
/*
* XXXGL: in the round-robin case we need to store
* the round-robin machine state in the rule, thus
* forwarding thread needs to modify rule.
*
* This is done w/o locking, because performance is assumed
* more important than round-robin precision.
*
* In the simpliest case we just update the "rpool->cur"
* pointer. However, if pool contains tables or dynamic
* addresses, then "tblidx" is also used to store machine
* state. Since "tblidx" is int, concurrent access to it can't
* lead to inconsistence, only to lost of precision.
*
* Things get worse, if table contains not hosts, but
* prefixes. In this case counter also stores machine state,
* and for IPv6 address, counter can't be updated atomically.
* Probably, using round-robin on a table containing IPv6
* prefixes (or even IPv4) would cause a panic.
*/
if (rpool->cur->addr.type == PF_ADDR_TABLE) {
if (!pfr_pool_get(rpool->cur->addr.p.tbl,
&rpool->tblidx, &rpool->counter, af))
goto get_addr;
} else if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) {
if (!pfr_pool_get(rpool->cur->addr.p.dyn->pfid_kt,
&rpool->tblidx, &rpool->counter, af))
goto get_addr;
} else if (pf_match_addr(0, raddr, rmask, &rpool->counter, af))
goto get_addr;
try_next:
if (TAILQ_NEXT(rpool->cur, entries) == NULL)
rpool->cur = TAILQ_FIRST(&rpool->list);
else
rpool->cur = TAILQ_NEXT(rpool->cur, entries);
if (rpool->cur->addr.type == PF_ADDR_TABLE) {
rpool->tblidx = -1;
if (pfr_pool_get(rpool->cur->addr.p.tbl,
&rpool->tblidx, &rpool->counter, af)) {
/* table contains no address of type 'af' */
if (rpool->cur != acur)
goto try_next;
return (1);
}
} else if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) {
rpool->tblidx = -1;
if (pfr_pool_get(rpool->cur->addr.p.dyn->pfid_kt,
&rpool->tblidx, &rpool->counter, af)) {
/* table contains no address of type 'af' */
if (rpool->cur != acur)
goto try_next;
return (1);
}
} else {
raddr = &rpool->cur->addr.v.a.addr;
rmask = &rpool->cur->addr.v.a.mask;
PF_ACPY(&rpool->counter, raddr, af);
}
get_addr:
PF_ACPY(naddr, &rpool->counter, af);
if (init_addr != NULL && PF_AZERO(init_addr, af))
PF_ACPY(init_addr, naddr, af);
PF_AINC(&rpool->counter, af);
break;
}
}
if (*sn != NULL)
PF_ACPY(&(*sn)->raddr, naddr, af);
if (V_pf_status.debug >= PF_DEBUG_MISC &&
(rpool->opts & PF_POOL_TYPEMASK) != PF_POOL_NONE) {
printf("pf_map_addr: selected address ");
pf_print_host(naddr, 0, af);
printf("\n");
}
return (0);
}
struct pf_rule *
pf_get_translation(struct pf_pdesc *pd, struct mbuf *m, int off, int direction,
struct pfi_kif *kif, struct pf_src_node **sn,
struct pf_state_key **skp, struct pf_state_key **nkp,
struct pf_addr *saddr, struct pf_addr *daddr,
uint16_t sport, uint16_t dport, struct pf_anchor_stackframe *anchor_stack)
{
struct pf_rule *r = NULL;
struct pf_addr *naddr;
uint16_t *nport;
PF_RULES_RASSERT();
KASSERT(*skp == NULL, ("*skp not NULL"));
KASSERT(*nkp == NULL, ("*nkp not NULL"));
if (direction == PF_OUT) {
r = pf_match_translation(pd, m, off, direction, kif, saddr,
sport, daddr, dport, PF_RULESET_BINAT, anchor_stack);
if (r == NULL)
r = pf_match_translation(pd, m, off, direction, kif,
saddr, sport, daddr, dport, PF_RULESET_NAT,
anchor_stack);
} else {
r = pf_match_translation(pd, m, off, direction, kif, saddr,
sport, daddr, dport, PF_RULESET_RDR, anchor_stack);
if (r == NULL)
r = pf_match_translation(pd, m, off, direction, kif,
saddr, sport, daddr, dport, PF_RULESET_BINAT,
anchor_stack);
}
if (r == NULL)
return (NULL);
switch (r->action) {
case PF_NONAT:
case PF_NOBINAT:
case PF_NORDR:
return (NULL);
}
*skp = pf_state_key_setup(pd, saddr, daddr, sport, dport);
if (*skp == NULL)
return (NULL);
*nkp = pf_state_key_clone(*skp);
if (*nkp == NULL) {
uma_zfree(V_pf_state_key_z, skp);
*skp = NULL;
return (NULL);
}
/* XXX We only modify one side for now. */
naddr = &(*nkp)->addr[1];
nport = &(*nkp)->port[1];
switch (r->action) {
case PF_NAT:
if (pf_get_sport(pd->af, pd->proto, r, saddr, sport, daddr,
dport, naddr, nport, r->rpool.proxy_port[0],
r->rpool.proxy_port[1], sn)) {
DPFPRINTF(PF_DEBUG_MISC,
("pf: NAT proxy port allocation (%u-%u) failed\n",
r->rpool.proxy_port[0], r->rpool.proxy_port[1]));
goto notrans;
}
break;
case PF_BINAT:
switch (direction) {
case PF_OUT:
if (r->rpool.cur->addr.type == PF_ADDR_DYNIFTL){
switch (pd->af) {
#ifdef INET
case AF_INET:
if (r->rpool.cur->addr.p.dyn->
pfid_acnt4 < 1)
goto notrans;
PF_POOLMASK(naddr,
&r->rpool.cur->addr.p.dyn->
pfid_addr4,
&r->rpool.cur->addr.p.dyn->
pfid_mask4, saddr, AF_INET);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
if (r->rpool.cur->addr.p.dyn->
pfid_acnt6 < 1)
goto notrans;
PF_POOLMASK(naddr,
&r->rpool.cur->addr.p.dyn->
pfid_addr6,
&r->rpool.cur->addr.p.dyn->
pfid_mask6, saddr, AF_INET6);
break;
#endif /* INET6 */
}
} else
PF_POOLMASK(naddr,
&r->rpool.cur->addr.v.a.addr,
&r->rpool.cur->addr.v.a.mask, saddr,
pd->af);
break;
case PF_IN:
if (r->src.addr.type == PF_ADDR_DYNIFTL) {
switch (pd->af) {
#ifdef INET
case AF_INET:
if (r->src.addr.p.dyn-> pfid_acnt4 < 1)
goto notrans;
PF_POOLMASK(naddr,
&r->src.addr.p.dyn->pfid_addr4,
&r->src.addr.p.dyn->pfid_mask4,
daddr, AF_INET);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
if (r->src.addr.p.dyn->pfid_acnt6 < 1)
goto notrans;
PF_POOLMASK(naddr,
&r->src.addr.p.dyn->pfid_addr6,
&r->src.addr.p.dyn->pfid_mask6,
daddr, AF_INET6);
break;
#endif /* INET6 */
}
} else
PF_POOLMASK(naddr, &r->src.addr.v.a.addr,
&r->src.addr.v.a.mask, daddr, pd->af);
break;
}
break;
case PF_RDR: {
if (pf_map_addr(pd->af, r, saddr, naddr, NULL, sn))
goto notrans;
if ((r->rpool.opts & PF_POOL_TYPEMASK) == PF_POOL_BITMASK)
PF_POOLMASK(naddr, naddr, &r->rpool.cur->addr.v.a.mask,
daddr, pd->af);
if (r->rpool.proxy_port[1]) {
uint32_t tmp_nport;
tmp_nport = ((ntohs(dport) - ntohs(r->dst.port[0])) %
(r->rpool.proxy_port[1] - r->rpool.proxy_port[0] +
1)) + r->rpool.proxy_port[0];
/* Wrap around if necessary. */
if (tmp_nport > 65535)
tmp_nport -= 65535;
*nport = htons((uint16_t)tmp_nport);
} else if (r->rpool.proxy_port[0])
*nport = htons(r->rpool.proxy_port[0]);
break;
}
default:
panic("%s: unknown action %u", __func__, r->action);
}
/* Return success only if translation really happened. */
if (bcmp(*skp, *nkp, sizeof(struct pf_state_key_cmp)))
return (r);
notrans:
uma_zfree(V_pf_state_key_z, *nkp);
uma_zfree(V_pf_state_key_z, *skp);
*skp = *nkp = NULL;
return (NULL);
}
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