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freebsd/sys/contrib/pf/net/pf.c
Max Laier 5c45a928b9 Vendor import of OpenBSD's packet filter (pf) as of OpenBSD 3.4
Approved by: bms(mentor), core (in general)
2004-02-26 02:04:28 +00:00

5264 lines
133 KiB
C

/* $OpenBSD: pf.c,v 1.390 2003/09/24 17:18:03 mcbride Exp $ */
/*
* Copyright (c) 2001 Daniel Hartmeier
* 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.
*
*/
#include "bpfilter.h"
#include "pflog.h"
#include "pfsync.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/filio.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/kernel.h>
#include <sys/time.h>
#include <sys/pool.h>
#include <net/if.h>
#include <net/if_types.h>
#include <net/bpf.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/tcp.h>
#include <netinet/tcp_seq.h>
#include <netinet/udp.h>
#include <netinet/ip_icmp.h>
#include <netinet/in_pcb.h>
#include <netinet/tcp_timer.h>
#include <netinet/tcp_var.h>
#include <netinet/udp_var.h>
#include <netinet/icmp_var.h>
#include <dev/rndvar.h>
#include <net/pfvar.h>
#include <net/if_pflog.h>
#include <net/if_pfsync.h>
#ifdef INET6
#include <netinet/ip6.h>
#include <netinet/in_pcb.h>
#include <netinet/icmp6.h>
#include <netinet6/nd6.h>
#endif /* INET6 */
#ifdef ALTQ
#include <altq/if_altq.h>
#endif
#define DPFPRINTF(n, x) if (pf_status.debug >= (n)) printf x
struct pf_state_tree;
/*
* Global variables
*/
struct pf_anchorqueue pf_anchors;
struct pf_ruleset pf_main_ruleset;
struct pf_altqqueue pf_altqs[2];
struct pf_palist pf_pabuf;
struct pf_altqqueue *pf_altqs_active;
struct pf_altqqueue *pf_altqs_inactive;
struct pf_status pf_status;
struct ifnet *status_ifp;
u_int32_t ticket_altqs_active;
u_int32_t ticket_altqs_inactive;
u_int32_t ticket_pabuf;
struct timeout pf_expire_to; /* expire timeout */
struct pool pf_tree_pl, pf_rule_pl, pf_addr_pl;
struct pool pf_state_pl, pf_altq_pl, pf_pooladdr_pl;
void pf_dynaddr_update(void *);
void pf_print_host(struct pf_addr *, u_int16_t, u_int8_t);
void pf_print_state(struct pf_state *);
void pf_print_flags(u_int8_t);
u_int16_t pf_cksum_fixup(u_int16_t, u_int16_t, u_int16_t,
u_int8_t);
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);
#ifdef INET6
void pf_change_a6(struct pf_addr *, u_int16_t *,
struct pf_addr *, u_int8_t);
#endif /* INET6 */
void pf_change_icmp(struct pf_addr *, u_int16_t *,
struct pf_addr *, struct pf_addr *, u_int16_t,
u_int16_t *, u_int16_t *, u_int16_t *,
u_int16_t *, u_int8_t, sa_family_t);
void pf_send_tcp(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);
void pf_send_icmp(struct mbuf *, u_int8_t, u_int8_t,
sa_family_t, struct pf_rule *);
struct pf_rule *pf_match_translation(struct pf_pdesc *, struct mbuf *,
int, int, struct ifnet *,
struct pf_addr *, u_int16_t, struct pf_addr *,
u_int16_t, int);
struct pf_rule *pf_get_translation(struct pf_pdesc *, struct mbuf *,
int, int, struct ifnet *,
struct pf_addr *, u_int16_t,
struct pf_addr *, u_int16_t,
struct pf_addr *, u_int16_t *);
int pf_test_tcp(struct pf_rule **, struct pf_state **,
int, struct ifnet *, struct mbuf *, int, int,
void *, struct pf_pdesc *, struct pf_rule **,
struct pf_ruleset **);
int pf_test_udp(struct pf_rule **, struct pf_state **,
int, struct ifnet *, struct mbuf *, int, int,
void *, struct pf_pdesc *, struct pf_rule **,
struct pf_ruleset **);
int pf_test_icmp(struct pf_rule **, struct pf_state **,
int, struct ifnet *, struct mbuf *, int, int,
void *, struct pf_pdesc *, struct pf_rule **,
struct pf_ruleset **);
int pf_test_other(struct pf_rule **, struct pf_state **,
int, struct ifnet *, struct mbuf *, int, void *,
struct pf_pdesc *, struct pf_rule **,
struct pf_ruleset **);
int pf_test_fragment(struct pf_rule **, int,
struct ifnet *, struct mbuf *, void *,
struct pf_pdesc *, struct pf_rule **,
struct pf_ruleset **);
int pf_test_state_tcp(struct pf_state **, int,
struct ifnet *, struct mbuf *, int, int,
void *, struct pf_pdesc *, u_short *);
int pf_test_state_udp(struct pf_state **, int,
struct ifnet *, struct mbuf *, int, int,
void *, struct pf_pdesc *);
int pf_test_state_icmp(struct pf_state **, int,
struct ifnet *, struct mbuf *, int, int,
void *, struct pf_pdesc *);
int pf_test_state_other(struct pf_state **, int,
struct ifnet *, struct pf_pdesc *);
struct pf_tag *pf_get_tag(struct mbuf *);
int pf_match_tag(struct mbuf *, struct pf_rule *,
struct pf_rule *, struct pf_rule *,
struct pf_tag *, int *);
void pf_hash(struct pf_addr *, struct pf_addr *,
struct pf_poolhashkey *, sa_family_t);
int pf_map_addr(u_int8_t, struct pf_pool *,
struct pf_addr *, struct pf_addr *,
struct pf_addr *);
int pf_get_sport(sa_family_t, u_int8_t, struct pf_pool *,
struct pf_addr *, struct pf_addr *, u_int16_t,
struct pf_addr *, u_int16_t*, u_int16_t, u_int16_t);
void pf_route(struct mbuf **, struct pf_rule *, int,
struct ifnet *, struct pf_state *);
void pf_route6(struct mbuf **, struct pf_rule *, int,
struct ifnet *, struct pf_state *);
int pf_socket_lookup(uid_t *, gid_t *, int, sa_family_t,
int, struct pf_pdesc *);
u_int8_t pf_get_wscale(struct mbuf *, int, u_int16_t,
sa_family_t);
u_int16_t pf_get_mss(struct mbuf *, int, u_int16_t,
sa_family_t);
u_int16_t pf_calc_mss(struct pf_addr *, sa_family_t,
u_int16_t);
void pf_set_rt_ifp(struct pf_state *,
struct pf_addr *);
int pf_check_proto_cksum(struct mbuf *, int, int,
u_int8_t, sa_family_t);
int pf_addr_wrap_neq(struct pf_addr_wrap *,
struct pf_addr_wrap *);
struct pf_pool_limit pf_pool_limits[PF_LIMIT_MAX] =
{ { &pf_state_pl, PFSTATE_HIWAT }, { &pf_frent_pl, PFFRAG_FRENT_HIWAT } };
#define STATE_LOOKUP() \
do { \
if (direction == PF_IN) \
*state = pf_find_state(&tree_ext_gwy, &key); \
else \
*state = pf_find_state(&tree_lan_ext, &key); \
if (*state == NULL) \
return (PF_DROP); \
if (direction == PF_OUT && \
(((*state)->rule.ptr->rt == PF_ROUTETO && \
(*state)->rule.ptr->direction == PF_OUT) || \
((*state)->rule.ptr->rt == PF_REPLYTO && \
(*state)->rule.ptr->direction == PF_IN)) && \
(*state)->rt_ifp != NULL && \
(*state)->rt_ifp != ifp) \
return (PF_PASS); \
} while (0)
#define STATE_TRANSLATE(s) \
(s)->lan.addr.addr32[0] != (s)->gwy.addr.addr32[0] || \
((s)->af == AF_INET6 && \
((s)->lan.addr.addr32[1] != (s)->gwy.addr.addr32[1] || \
(s)->lan.addr.addr32[2] != (s)->gwy.addr.addr32[2] || \
(s)->lan.addr.addr32[3] != (s)->gwy.addr.addr32[3])) || \
(s)->lan.port != (s)->gwy.port
static __inline int pf_state_compare(struct pf_tree_node *,
struct pf_tree_node *);
struct pf_state_tree tree_lan_ext, tree_ext_gwy;
RB_GENERATE(pf_state_tree, pf_tree_node, entry, pf_state_compare);
static __inline int
pf_state_compare(struct pf_tree_node *a, struct pf_tree_node *b)
{
int diff;
if ((diff = a->proto - b->proto) != 0)
return (diff);
if ((diff = a->af - b->af) != 0)
return (diff);
switch (a->af) {
#ifdef INET
case AF_INET:
if (a->addr[0].addr32[0] > b->addr[0].addr32[0])
return (1);
if (a->addr[0].addr32[0] < b->addr[0].addr32[0])
return (-1);
if (a->addr[1].addr32[0] > b->addr[1].addr32[0])
return (1);
if (a->addr[1].addr32[0] < b->addr[1].addr32[0])
return (-1);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
if (a->addr[0].addr32[3] > b->addr[0].addr32[3])
return (1);
if (a->addr[0].addr32[3] < b->addr[0].addr32[3])
return (-1);
if (a->addr[1].addr32[3] > b->addr[1].addr32[3])
return (1);
if (a->addr[1].addr32[3] < b->addr[1].addr32[3])
return (-1);
if (a->addr[0].addr32[2] > b->addr[0].addr32[2])
return (1);
if (a->addr[0].addr32[2] < b->addr[0].addr32[2])
return (-1);
if (a->addr[1].addr32[2] > b->addr[1].addr32[2])
return (1);
if (a->addr[1].addr32[2] < b->addr[1].addr32[2])
return (-1);
if (a->addr[0].addr32[1] > b->addr[0].addr32[1])
return (1);
if (a->addr[0].addr32[1] < b->addr[0].addr32[1])
return (-1);
if (a->addr[1].addr32[1] > b->addr[1].addr32[1])
return (1);
if (a->addr[1].addr32[1] < b->addr[1].addr32[1])
return (-1);
if (a->addr[0].addr32[0] > b->addr[0].addr32[0])
return (1);
if (a->addr[0].addr32[0] < b->addr[0].addr32[0])
return (-1);
if (a->addr[1].addr32[0] > b->addr[1].addr32[0])
return (1);
if (a->addr[1].addr32[0] < b->addr[1].addr32[0])
return (-1);
break;
#endif /* INET6 */
}
if ((diff = a->port[0] - b->port[0]) != 0)
return (diff);
if ((diff = a->port[1] - b->port[1]) != 0)
return (diff);
return (0);
}
#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
struct pf_state *
pf_find_state(struct pf_state_tree *tree, struct pf_tree_node *key)
{
struct pf_tree_node *k;
pf_status.fcounters[FCNT_STATE_SEARCH]++;
k = RB_FIND(pf_state_tree, tree, key);
if (k)
return (k->state);
else
return (NULL);
}
int
pf_insert_state(struct pf_state *state)
{
struct pf_tree_node *keya, *keyb;
keya = pool_get(&pf_tree_pl, PR_NOWAIT);
if (keya == NULL)
return (-1);
keya->state = state;
keya->proto = state->proto;
keya->af = state->af;
PF_ACPY(&keya->addr[0], &state->lan.addr, state->af);
keya->port[0] = state->lan.port;
PF_ACPY(&keya->addr[1], &state->ext.addr, state->af);
keya->port[1] = state->ext.port;
/* Thou MUST NOT insert multiple duplicate keys */
if (RB_INSERT(pf_state_tree, &tree_lan_ext, keya) != NULL) {
if (pf_status.debug >= PF_DEBUG_MISC) {
printf("pf: state insert failed: tree_lan_ext");
printf(" lan: ");
pf_print_host(&state->lan.addr, state->lan.port,
state->af);
printf(" gwy: ");
pf_print_host(&state->gwy.addr, state->gwy.port,
state->af);
printf(" ext: ");
pf_print_host(&state->ext.addr, state->ext.port,
state->af);
printf("\n");
}
pool_put(&pf_tree_pl, keya);
return (-1);
}
keyb = pool_get(&pf_tree_pl, PR_NOWAIT);
if (keyb == NULL) {
/* Need to pull out the other state */
RB_REMOVE(pf_state_tree, &tree_lan_ext, keya);
pool_put(&pf_tree_pl, keya);
return (-1);
}
keyb->state = state;
keyb->proto = state->proto;
keyb->af = state->af;
PF_ACPY(&keyb->addr[0], &state->ext.addr, state->af);
keyb->port[0] = state->ext.port;
PF_ACPY(&keyb->addr[1], &state->gwy.addr, state->af);
keyb->port[1] = state->gwy.port;
if (RB_INSERT(pf_state_tree, &tree_ext_gwy, keyb) != NULL) {
if (pf_status.debug >= PF_DEBUG_MISC) {
printf("pf: state insert failed: tree_ext_gwy");
printf(" lan: ");
pf_print_host(&state->lan.addr, state->lan.port,
state->af);
printf(" gwy: ");
pf_print_host(&state->gwy.addr, state->gwy.port,
state->af);
printf(" ext: ");
pf_print_host(&state->ext.addr, state->ext.port,
state->af);
printf("\n");
}
RB_REMOVE(pf_state_tree, &tree_lan_ext, keya);
pool_put(&pf_tree_pl, keya);
pool_put(&pf_tree_pl, keyb);
return (-1);
}
pf_status.fcounters[FCNT_STATE_INSERT]++;
pf_status.states++;
#if NPFSYNC
pfsync_insert_state(state);
#endif
return (0);
}
void
pf_purge_timeout(void *arg)
{
struct timeout *to = arg;
int s;
s = splsoftnet();
pf_purge_expired_states();
pf_purge_expired_fragments();
splx(s);
timeout_add(to, pf_default_rule.timeout[PFTM_INTERVAL] * hz);
}
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.tv_sec);
if (state->timeout == PFTM_UNTIL_PACKET)
return (0);
KASSERT(state->timeout < PFTM_MAX);
timeout = state->rule.ptr->timeout[state->timeout];
if (!timeout)
timeout = 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 = state->rule.ptr->states;
} else {
start = pf_default_rule.timeout[PFTM_ADAPTIVE_START];
end = pf_default_rule.timeout[PFTM_ADAPTIVE_END];
states = pf_status.states;
}
if (end && states > start && start < end) {
if (states < end)
return (state->expire + timeout * (end - states) /
(end - start));
else
return (time.tv_sec);
}
return (state->expire + timeout);
}
void
pf_purge_expired_states(void)
{
struct pf_tree_node *cur, *peer, *next;
struct pf_tree_node key;
for (cur = RB_MIN(pf_state_tree, &tree_ext_gwy); cur; cur = next) {
next = RB_NEXT(pf_state_tree, &tree_ext_gwy, cur);
if (pf_state_expires(cur->state) <= time.tv_sec) {
if (cur->state->src.state == PF_TCPS_PROXY_DST)
pf_send_tcp(cur->state->rule.ptr,
cur->state->af,
&cur->state->ext.addr,
&cur->state->lan.addr,
cur->state->ext.port,
cur->state->lan.port,
cur->state->src.seqhi,
cur->state->src.seqlo + 1,
0,
TH_RST|TH_ACK, 0, 0);
RB_REMOVE(pf_state_tree, &tree_ext_gwy, cur);
/* Need this key's peer (in the other tree) */
key.state = cur->state;
key.proto = cur->state->proto;
key.af = cur->state->af;
PF_ACPY(&key.addr[0], &cur->state->lan.addr,
cur->state->af);
key.port[0] = cur->state->lan.port;
PF_ACPY(&key.addr[1], &cur->state->ext.addr,
cur->state->af);
key.port[1] = cur->state->ext.port;
peer = RB_FIND(pf_state_tree, &tree_lan_ext, &key);
KASSERT(peer);
KASSERT(peer->state == cur->state);
RB_REMOVE(pf_state_tree, &tree_lan_ext, peer);
#if NPFSYNC
pfsync_delete_state(cur->state);
#endif
if (--cur->state->rule.ptr->states <= 0)
pf_rm_rule(NULL, cur->state->rule.ptr);
if (cur->state->nat_rule.ptr != NULL)
if (--cur->state->nat_rule.ptr->states <= 0)
pf_rm_rule(NULL,
cur->state->nat_rule.ptr);
if (cur->state->anchor.ptr != NULL)
if (--cur->state->anchor.ptr->states <= 0)
pf_rm_rule(NULL,
cur->state->anchor.ptr);
pf_normalize_tcp_cleanup(cur->state);
pool_put(&pf_state_pl, cur->state);
pool_put(&pf_tree_pl, cur);
pool_put(&pf_tree_pl, peer);
pf_status.fcounters[FCNT_STATE_REMOVALS]++;
pf_status.states--;
}
}
}
int
pf_tbladdr_setup(struct pf_ruleset *rs, struct pf_addr_wrap *aw)
{
if (aw->type != PF_ADDR_TABLE)
return (0);
if ((aw->p.tbl = pfr_attach_table(rs, aw->v.tblname)) == NULL)
return (1);
return (0);
}
void
pf_tbladdr_remove(struct pf_addr_wrap *aw)
{
if (aw->type != PF_ADDR_TABLE || aw->p.tbl == NULL)
return;
pfr_detach_table(aw->p.tbl);
aw->p.tbl = NULL;
}
void
pf_tbladdr_copyout(struct pf_addr_wrap *aw)
{
struct pfr_ktable *kt = aw->p.tbl;
if (aw->type != PF_ADDR_TABLE || kt == NULL)
return;
if (!(kt->pfrkt_flags & PFR_TFLAG_ACTIVE) && kt->pfrkt_root != NULL)
kt = kt->pfrkt_root;
aw->p.tbl = NULL;
aw->p.tblcnt = (kt->pfrkt_flags & PFR_TFLAG_ACTIVE) ?
kt->pfrkt_cnt : -1;
}
int
pf_dynaddr_setup(struct pf_addr_wrap *aw, sa_family_t af)
{
if (aw->type != PF_ADDR_DYNIFTL)
return (0);
aw->p.dyn = pool_get(&pf_addr_pl, PR_NOWAIT);
if (aw->p.dyn == NULL)
return (1);
bcopy(aw->v.ifname, aw->p.dyn->ifname, sizeof(aw->p.dyn->ifname));
aw->p.dyn->ifp = ifunit(aw->p.dyn->ifname);
if (aw->p.dyn->ifp == NULL) {
pool_put(&pf_addr_pl, aw->p.dyn);
aw->p.dyn = NULL;
return (1);
}
aw->p.dyn->addr = &aw->v.a.addr;
aw->p.dyn->af = af;
aw->p.dyn->undefined = 1;
aw->p.dyn->hook_cookie = hook_establish(
aw->p.dyn->ifp->if_addrhooks, 1,
pf_dynaddr_update, aw->p.dyn);
if (aw->p.dyn->hook_cookie == NULL) {
pool_put(&pf_addr_pl, aw->p.dyn);
aw->p.dyn = NULL;
return (1);
}
pf_dynaddr_update(aw->p.dyn);
return (0);
}
void
pf_dynaddr_update(void *p)
{
struct pf_addr_dyn *ad = (struct pf_addr_dyn *)p;
struct ifaddr *ia;
int s, changed = 0;
if (ad == NULL || ad->ifp == NULL)
panic("pf_dynaddr_update");
s = splsoftnet();
TAILQ_FOREACH(ia, &ad->ifp->if_addrlist, ifa_list)
if (ia->ifa_addr != NULL &&
ia->ifa_addr->sa_family == ad->af) {
if (ad->af == AF_INET) {
struct in_addr *a, *b;
a = &ad->addr->v4;
b = &((struct sockaddr_in *)ia->ifa_addr)
->sin_addr;
if (ad->undefined ||
memcmp(a, b, sizeof(*a))) {
bcopy(b, a, sizeof(*a));
changed = 1;
}
} else if (ad->af == AF_INET6) {
struct in6_addr *a, *b;
a = &ad->addr->v6;
b = &((struct sockaddr_in6 *)ia->ifa_addr)
->sin6_addr;
if (ad->undefined ||
memcmp(a, b, sizeof(*a))) {
bcopy(b, a, sizeof(*a));
changed = 1;
}
}
if (changed)
ad->undefined = 0;
break;
}
if (ia == NULL)
ad->undefined = 1;
splx(s);
}
void
pf_dynaddr_remove(struct pf_addr_wrap *aw)
{
if (aw->type != PF_ADDR_DYNIFTL || aw->p.dyn == NULL)
return;
hook_disestablish(aw->p.dyn->ifp->if_addrhooks,
aw->p.dyn->hook_cookie);
pool_put(&pf_addr_pl, aw->p.dyn);
aw->p.dyn = NULL;
}
void
pf_dynaddr_copyout(struct pf_addr_wrap *aw)
{
if (aw->type != PF_ADDR_DYNIFTL || aw->p.dyn == NULL)
return;
bcopy(aw->p.dyn->ifname, aw->v.ifname, sizeof(aw->v.ifname));
aw->p.dyn = (struct pf_addr_dyn *)1;
}
void
pf_print_host(struct pf_addr *addr, u_int16_t p, sa_family_t af)
{
switch (af) {
#ifdef INET
case AF_INET: {
u_int32_t a = ntohl(addr->addr32[0]);
printf("%u.%u.%u.%u", (a>>24)&255, (a>>16)&255,
(a>>8)&255, a&255);
if (p) {
p = ntohs(p);
printf(":%u", p);
}
break;
}
#endif /* INET */
#ifdef INET6
case AF_INET6: {
u_int16_t b;
u_int8_t i, curstart = 255, curend = 0,
maxstart = 0, maxend = 0;
for (i = 0; i < 8; i++) {
if (!addr->addr16[i]) {
if (curstart == 255)
curstart = i;
else
curend = i;
} else {
if (curstart) {
if ((curend - curstart) >
(maxend - maxstart)) {
maxstart = curstart;
maxend = curend;
curstart = 255;
}
}
}
}
for (i = 0; i < 8; i++) {
if (i >= maxstart && i <= maxend) {
if (maxend != 7) {
if (i == maxstart)
printf(":");
} else {
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)
{
switch (s->proto) {
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 ", s->proto);
break;
}
pf_print_host(&s->lan.addr, s->lan.port, s->af);
printf(" ");
pf_print_host(&s->gwy.addr, s->gwy.port, s->af);
printf(" ");
pf_print_host(&s->ext.addr, s->ext.port, s->af);
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->ifp != prev->ifp || 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.not != prev->src.not ||
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.not != prev->dst.not ||
pf_addr_wrap_neq(&cur->dst.addr, &prev->dst.addr))
PF_SET_SKIP_STEPS(PF_SKIP_DST_ADDR);
if (cur->dst.port[0] != prev->dst.port[0] ||
cur->dst.port[1] != prev->dst.port[1] ||
cur->dst.port_op != prev->dst.port_op)
PF_SET_SKIP_STEPS(PF_SKIP_DST_PORT);
prev = cur;
cur = TAILQ_NEXT(cur, entries);
}
for (i = 0; i < PF_SKIP_COUNT; ++i)
PF_SET_SKIP_STEPS(i);
}
int
pf_addr_wrap_neq(struct pf_addr_wrap *aw1, struct pf_addr_wrap *aw2)
{
if (aw1->type != aw2->type)
return (1);
switch (aw1->type) {
case PF_ADDR_ADDRMASK:
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:
if (aw1->p.dyn->ifp != aw2->p.dyn->ifp)
return (1);
if (PF_ANEQ(&aw1->v.a.mask, &aw2->v.a.mask, 0))
return (1);
return (0);
case PF_ADDR_NOROUTE:
return (0);
case PF_ADDR_TABLE:
return (aw1->p.tbl != aw2->p.tbl);
default:
printf("invalid address type: %d\n", aw1->type);
return (1);
}
}
void
pf_rule_set_qid(struct pf_rulequeue *rules)
{
struct pf_rule *rule;
TAILQ_FOREACH(rule, rules, entries)
if (rule->qname[0] != 0) {
rule->qid = pf_qname_to_qid(rule->qname);
if (rule->pqname[0] != 0)
rule->pqid = pf_qname_to_qid(rule->pqname);
else
rule->pqid = rule->qid;
}
}
u_int32_t
pf_qname_to_qid(char *qname)
{
struct pf_altq *altq;
TAILQ_FOREACH(altq, pf_altqs_active, entries)
if (!strcmp(altq->qname, qname))
return (altq->qid);
return (0);
}
void
pf_update_anchor_rules()
{
struct pf_rule *rule;
int i;
for (i = 0; i < PF_RULESET_MAX; ++i)
TAILQ_FOREACH(rule, pf_main_ruleset.rules[i].active.ptr,
entries)
if (rule->anchorname[0])
rule->anchor = pf_find_anchor(rule->anchorname);
else
rule->anchor = NULL;
}
u_int16_t
pf_cksum_fixup(u_int16_t cksum, u_int16_t old, u_int16_t new, u_int8_t udp)
{
u_int32_t l;
if (udp && !cksum)
return (0x0000);
l = cksum + old - new;
l = (l >> 16) + (l & 65535);
l = l & 65535;
if (udp && !l)
return (0xFFFF);
return (l);
}
void
pf_change_ap(struct pf_addr *a, u_int16_t *p, u_int16_t *ic, u_int16_t *pc,
struct pf_addr *an, u_int16_t pn, u_int8_t u, sa_family_t af)
{
struct pf_addr ao;
u_int16_t po = *p;
PF_ACPY(&ao, a, af);
PF_ACPY(a, an, af);
*p = pn;
switch (af) {
#ifdef INET
case AF_INET:
*ic = pf_cksum_fixup(pf_cksum_fixup(*ic,
ao.addr16[0], an->addr16[0], 0),
ao.addr16[1], an->addr16[1], 0);
*p = pn;
*pc = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(*pc,
ao.addr16[0], an->addr16[0], u),
ao.addr16[1], an->addr16[1], u),
po, pn, u);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
*pc = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(*pc,
ao.addr16[0], an->addr16[0], u),
ao.addr16[1], an->addr16[1], u),
ao.addr16[2], an->addr16[2], u),
ao.addr16[3], an->addr16[3], u),
ao.addr16[4], an->addr16[4], u),
ao.addr16[5], an->addr16[5], u),
ao.addr16[6], an->addr16[6], u),
ao.addr16[7], an->addr16[7], u),
po, pn, u);
break;
#endif /* INET6 */
}
}
/* Changes a u_int32_t. Uses a void * so there are no align restrictions */
void
pf_change_a(void *a, u_int16_t *c, u_int32_t an, u_int8_t u)
{
u_int32_t ao;
memcpy(&ao, a, sizeof(ao));
memcpy(a, &an, sizeof(u_int32_t));
*c = pf_cksum_fixup(pf_cksum_fixup(*c, ao / 65536, an / 65536, u),
ao % 65536, an % 65536, u);
}
#ifdef INET6
void
pf_change_a6(struct pf_addr *a, u_int16_t *c, struct pf_addr *an, u_int8_t u)
{
struct pf_addr ao;
PF_ACPY(&ao, a, AF_INET6);
PF_ACPY(a, an, AF_INET6);
*c = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
pf_cksum_fixup(pf_cksum_fixup(*c,
ao.addr16[0], an->addr16[0], u),
ao.addr16[1], an->addr16[1], u),
ao.addr16[2], an->addr16[2], u),
ao.addr16[3], an->addr16[3], u),
ao.addr16[4], an->addr16[4], u),
ao.addr16[5], an->addr16[5], u),
ao.addr16[6], an->addr16[6], u),
ao.addr16[7], an->addr16[7], u);
}
#endif /* INET6 */
void
pf_change_icmp(struct pf_addr *ia, u_int16_t *ip, struct pf_addr *oa,
struct pf_addr *na, u_int16_t np, u_int16_t *pc, u_int16_t *h2c,
u_int16_t *ic, u_int16_t *hc, u_int8_t u, sa_family_t af)
{
struct pf_addr oia, ooa;
PF_ACPY(&oia, ia, af);
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 */
}
/* Change outer ip address, fix outer ip or icmpv6 checksum. */
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 */
}
}
void
pf_send_tcp(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)
{
struct mbuf *m;
struct m_tag *mtag;
int len, tlen;
#ifdef INET
struct ip *h;
#endif /* INET */
#ifdef INET6
struct ip6_hdr *h6;
#endif /* INET6 */
struct tcphdr *th;
char *opt;
/* maximum segment size tcp option */
tlen = sizeof(struct tcphdr);
if (mss)
tlen += 4;
switch (af) {
#ifdef INET
case AF_INET:
len = sizeof(struct ip) + tlen;
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
len = sizeof(struct ip6_hdr) + tlen;
break;
#endif /* INET6 */
}
/* create outgoing mbuf */
mtag = m_tag_get(PACKET_TAG_PF_GENERATED, 0, M_NOWAIT);
if (mtag == NULL)
return;
m = m_gethdr(M_DONTWAIT, MT_HEADER);
if (m == NULL) {
m_tag_free(mtag);
return;
}
m_tag_prepend(m, mtag);
#ifdef ALTQ
if (r != NULL && r->qid) {
struct altq_tag *atag;
mtag = m_tag_get(PACKET_TAG_PF_QID, sizeof(*atag), M_NOWAIT);
if (mtag != NULL) {
atag = (struct altq_tag *)(mtag + 1);
atag->qid = r->qid;
/* add hints for ecn */
atag->af = af;
atag->hdr = mtod(m, struct ip *);
m_tag_prepend(m, mtag);
}
}
#endif
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_len = htons(len);
h->ip_off = htons(ip_mtudisc ? IP_DF : 0);
h->ip_ttl = ttl ? ttl : ip_defttl;
h->ip_sum = 0;
ip_output(m, (void *)NULL, (void *)NULL, 0, (void *)NULL,
(void *)NULL);
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;
ip6_output(m, NULL, NULL, 0, NULL, NULL);
break;
#endif /* INET6 */
}
}
void
pf_send_icmp(struct mbuf *m, u_int8_t type, u_int8_t code, sa_family_t af,
struct pf_rule *r)
{
struct m_tag *mtag;
struct mbuf *m0;
mtag = m_tag_get(PACKET_TAG_PF_GENERATED, 0, M_NOWAIT);
if (mtag == NULL)
return;
m0 = m_copy(m, 0, M_COPYALL);
if (m0 == NULL) {
m_tag_free(mtag);
return;
}
m_tag_prepend(m0, mtag);
#ifdef ALTQ
if (r->qid) {
struct altq_tag *atag;
mtag = m_tag_get(PACKET_TAG_PF_QID, sizeof(*atag), M_NOWAIT);
if (mtag != NULL) {
atag = (struct altq_tag *)(mtag + 1);
atag->qid = r->qid;
/* add hints for ecn */
atag->af = af;
atag->hdr = mtod(m0, struct ip *);
m_tag_prepend(m0, mtag);
}
}
#endif
switch (af) {
#ifdef INET
case AF_INET:
icmp_error(m0, type, code, 0, 0);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
icmp6_error(m0, type, code, 0);
break;
#endif /* INET6 */
}
}
/*
* Return 1 if the addresses a and b match (with mask m), otherwise return 0.
* If n is 0, they match if they are equal. If n is != 0, they match if they
* are different.
*/
int
pf_match_addr(u_int8_t n, struct pf_addr *a, struct pf_addr *m,
struct pf_addr *b, sa_family_t af)
{
int match = 0;
switch (af) {
#ifdef INET
case AF_INET:
if ((a->addr32[0] & m->addr32[0]) ==
(b->addr32[0] & m->addr32[0]))
match++;
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
if (((a->addr32[0] & m->addr32[0]) ==
(b->addr32[0] & m->addr32[0])) &&
((a->addr32[1] & m->addr32[1]) ==
(b->addr32[1] & m->addr32[1])) &&
((a->addr32[2] & m->addr32[2]) ==
(b->addr32[2] & m->addr32[2])) &&
((a->addr32[3] & m->addr32[3]) ==
(b->addr32[3] & m->addr32[3])))
match++;
break;
#endif /* INET6 */
}
if (match) {
if (n)
return (0);
else
return (1);
} else {
if (n)
return (1);
else
return (0);
}
}
int
pf_match(u_int8_t op, u_int32_t a1, u_int32_t a2, u_int32_t p)
{
switch (op) {
case PF_OP_IRG:
return ((p > a1) && (p < a2));
case PF_OP_XRG:
return ((p < a1) || (p > a2));
case PF_OP_RRG:
return ((p >= a1) && (p <= a2));
case PF_OP_EQ:
return (p == a1);
case PF_OP_NE:
return (p != a1);
case PF_OP_LT:
return (p < a1);
case PF_OP_LE:
return (p <= a1);
case PF_OP_GT:
return (p > a1);
case PF_OP_GE:
return (p >= a1);
}
return (0); /* never reached */
}
int
pf_match_port(u_int8_t op, u_int16_t a1, u_int16_t a2, u_int16_t p)
{
NTOHS(a1);
NTOHS(a2);
NTOHS(p);
return (pf_match(op, a1, a2, p));
}
int
pf_match_uid(u_int8_t op, uid_t a1, uid_t a2, uid_t u)
{
if (u == UID_MAX && op != PF_OP_EQ && op != PF_OP_NE)
return (0);
return (pf_match(op, a1, a2, u));
}
int
pf_match_gid(u_int8_t op, gid_t a1, gid_t a2, gid_t g)
{
if (g == GID_MAX && op != PF_OP_EQ && op != PF_OP_NE)
return (0);
return (pf_match(op, a1, a2, g));
}
struct pf_tag *
pf_get_tag(struct mbuf *m)
{
struct m_tag *mtag;
if ((mtag = m_tag_find(m, PACKET_TAG_PF_TAG, NULL)) != NULL)
return ((struct pf_tag *)(mtag + 1));
else
return (NULL);
}
int
pf_match_tag(struct mbuf *m, struct pf_rule *r, struct pf_rule *nat,
struct pf_rule *rdr, struct pf_tag *pftag, int *tag)
{
if (*tag == -1) { /* find mbuf tag */
pftag = pf_get_tag(m);
if (pftag != NULL)
*tag = pftag->tag;
else
*tag = 0;
if (nat != NULL && nat->tag)
*tag = nat->tag;
if (rdr != NULL && rdr->tag)
*tag = rdr->tag;
}
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_tag *pftag, int tag)
{
struct m_tag *mtag;
if (tag <= 0)
return (0);
if (pftag == NULL) {
mtag = m_tag_get(PACKET_TAG_PF_TAG, sizeof(*pftag), M_NOWAIT);
if (mtag == NULL)
return (1);
((struct pf_tag *)(mtag + 1))->tag = tag;
m_tag_prepend(m, mtag);
} else
pftag->tag = tag;
return (0);
}
#define PF_STEP_INTO_ANCHOR(r, a, s, n) \
do { \
if ((r) == NULL || (r)->anchor == NULL || \
(s) != NULL || (a) != NULL) \
panic("PF_STEP_INTO_ANCHOR"); \
(a) = (r); \
(s) = TAILQ_FIRST(&(r)->anchor->rulesets); \
(r) = NULL; \
while ((s) != NULL && ((r) = \
TAILQ_FIRST((s)->rules[n].active.ptr)) == NULL) \
(s) = TAILQ_NEXT((s), entries); \
if ((r) == NULL) { \
(r) = TAILQ_NEXT((a), entries); \
(a) = NULL; \
} \
} while (0)
#define PF_STEP_OUT_OF_ANCHOR(r, a, s, n) \
do { \
if ((r) != NULL || (a) == NULL || (s) == NULL) \
panic("PF_STEP_OUT_OF_ANCHOR"); \
(s) = TAILQ_NEXT((s), entries); \
while ((s) != NULL && ((r) = \
TAILQ_FIRST((s)->rules[n].active.ptr)) == NULL) \
(s) = TAILQ_NEXT((s), entries); \
if ((r) == NULL) { \
(r) = TAILQ_NEXT((a), entries); \
(a) = NULL; \
} \
} while (0)
#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, u_int8_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 */
#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
*/
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 */
}
}
int
pf_map_addr(u_int8_t af, struct pf_pool *rpool, struct pf_addr *saddr,
struct pf_addr *naddr, struct pf_addr *init_addr)
{
unsigned char hash[16];
struct pf_addr *raddr;
struct pf_addr *rmask;
struct pf_pooladdr *acur = rpool->cur;
if (rpool->cur->addr.type == PF_ADDR_NOROUTE)
return (1);
if (rpool->cur->addr.type == PF_ADDR_DYNIFTL &&
rpool->cur->addr.p.dyn->undefined)
return (1);
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] = arc4random();
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
if (rmask->addr32[3] != 0xffffffff)
rpool->counter.addr32[3] = arc4random();
else
break;
if (rmask->addr32[2] != 0xffffffff)
rpool->counter.addr32[2] = arc4random();
else
break;
if (rmask->addr32[1] != 0xffffffff)
rpool->counter.addr32[1] = arc4random();
else
break;
if (rmask->addr32[0] != 0xffffffff)
rpool->counter.addr32[0] = 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:
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:
if (rpool->cur->addr.type == PF_ADDR_TABLE) {
if (!pfr_pool_get(rpool->cur->addr.p.tbl,
&rpool->tblidx, &rpool->counter,
&raddr, &rmask, af))
goto get_addr;
} else if (pf_match_addr(0, raddr, rmask, &rpool->counter, af))
goto get_addr;
try_next:
if ((rpool->cur = TAILQ_NEXT(rpool->cur, entries)) == NULL)
rpool->cur = TAILQ_FIRST(&rpool->list);
if (rpool->cur->addr.type == PF_ADDR_TABLE) {
rpool->tblidx = -1;
if (pfr_pool_get(rpool->cur->addr.p.tbl,
&rpool->tblidx, &rpool->counter,
&raddr, &rmask, af)) {
/* table contain 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);
PF_AINC(&rpool->counter, af);
break;
}
if (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);
}
int
pf_get_sport(sa_family_t af, u_int8_t proto, struct pf_pool *rpool,
struct pf_addr *saddr, struct pf_addr *daddr, u_int16_t dport,
struct pf_addr *naddr, u_int16_t *nport, u_int16_t low, u_int16_t high)
{
struct pf_tree_node key;
struct pf_addr init_addr;
u_int16_t cut;
bzero(&init_addr, sizeof(init_addr));
if (pf_map_addr(af, rpool, saddr, naddr, &init_addr))
return (1);
do {
key.af = af;
key.proto = proto;
PF_ACPY(&key.addr[0], daddr, key.af);
PF_ACPY(&key.addr[1], naddr, key.af);
key.port[0] = dport;
/*
* port search; start random, step;
* similar 2 portloop in in_pcbbind
*/
if (!(proto == IPPROTO_TCP || proto == IPPROTO_UDP)) {
key.port[1] = 0;
if (pf_find_state(&tree_ext_gwy, &key) == NULL)
return (0);
} else if (low == 0 && high == 0) {
key.port[1] = *nport;
if (pf_find_state(&tree_ext_gwy, &key) == NULL) {
return (0);
}
} else if (low == high) {
key.port[1] = htons(low);
if (pf_find_state(&tree_ext_gwy, &key) == NULL) {
*nport = htons(low);
return (0);
}
} else {
u_int16_t tmp;
if (low > high) {
tmp = low;
low = high;
high = tmp;
}
/* low < high */
cut = arc4random() % (1 + high - low) + low;
/* low <= cut <= high */
for (tmp = cut; tmp <= high; ++(tmp)) {
key.port[1] = htons(tmp);
if (pf_find_state(&tree_ext_gwy, &key) ==
NULL) {
*nport = htons(tmp);
return (0);
}
}
for (tmp = cut - 1; tmp >= low; --(tmp)) {
key.port[1] = htons(tmp);
if (pf_find_state(&tree_ext_gwy, &key) ==
NULL) {
*nport = htons(tmp);
return (0);
}
}
}
switch (rpool->opts & PF_POOL_TYPEMASK) {
case PF_POOL_RANDOM:
case PF_POOL_ROUNDROBIN:
if (pf_map_addr(af, rpool, saddr, naddr, &init_addr))
return (1);
break;
case PF_POOL_NONE:
case PF_POOL_SRCHASH:
case PF_POOL_BITMASK:
default:
return (1);
break;
}
} while (! PF_AEQ(&init_addr, naddr, af) );
return (1); /* none available */
}
struct pf_rule *
pf_match_translation(struct pf_pdesc *pd, struct mbuf *m, int off,
int direction, struct ifnet *ifp, struct pf_addr *saddr, u_int16_t sport,
struct pf_addr *daddr, u_int16_t dport, int rs_num)
{
struct pf_rule *r, *rm = NULL, *anchorrule = NULL;
struct pf_ruleset *ruleset = NULL;
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 (r->ifp != NULL && ((r->ifp != ifp && !r->ifnot) ||
(r->ifp == ifp && 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->not))
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->not))
r = r->skip[PF_SKIP_DST_ADDR].ptr;
else if (xdst != NULL && PF_MISMATCHAW(xdst, daddr, pd->af, 0))
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->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->anchorname[0] && r->anchor == NULL)
r = TAILQ_NEXT(r, entries);
else if (r->anchor == NULL)
rm = r;
else
PF_STEP_INTO_ANCHOR(r, anchorrule, ruleset, rs_num);
if (r == NULL && anchorrule != NULL)
PF_STEP_OUT_OF_ANCHOR(r, anchorrule, ruleset,
rs_num);
}
if (rm != NULL && (rm->action == PF_NONAT ||
rm->action == PF_NORDR || rm->action == PF_NOBINAT))
return (NULL);
return (rm);
}
struct pf_rule *
pf_get_translation(struct pf_pdesc *pd, struct mbuf *m, int off, int direction,
struct ifnet *ifp,
struct pf_addr *saddr, u_int16_t sport,
struct pf_addr *daddr, u_int16_t dport,
struct pf_addr *naddr, u_int16_t *nport)
{
struct pf_rule *r = NULL;
if (direction == PF_OUT) {
r = pf_match_translation(pd, m, off, direction, ifp, saddr,
sport, daddr, dport, PF_RULESET_BINAT);
if (r == NULL)
r = pf_match_translation(pd, m, off, direction, ifp,
saddr, sport, daddr, dport, PF_RULESET_NAT);
} else {
r = pf_match_translation(pd, m, off, direction, ifp, saddr,
sport, daddr, dport, PF_RULESET_RDR);
if (r == NULL)
r = pf_match_translation(pd, m, off, direction, ifp,
saddr, sport, daddr, dport, PF_RULESET_BINAT);
}
if (r != NULL) {
switch (r->action) {
case PF_NONAT:
case PF_NOBINAT:
case PF_NORDR:
return (NULL);
break;
case PF_NAT:
if (pf_get_sport(pd->af, pd->proto, &r->rpool, saddr,
daddr, dport, naddr, nport, r->rpool.proxy_port[0],
r->rpool.proxy_port[1])) {
DPFPRINTF(PF_DEBUG_MISC,
("pf: NAT proxy port allocation "
"(%u-%u) failed\n",
r->rpool.proxy_port[0],
r->rpool.proxy_port[1]));
return (NULL);
}
break;
case PF_BINAT:
switch (direction) {
case PF_OUT:
if (r->rpool.cur->addr.type ==
PF_ADDR_DYNIFTL &&
r->rpool.cur->addr.p.dyn->undefined)
return (NULL);
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 &&
r->src.addr.p.dyn->undefined)
return (NULL);
else
PF_POOLMASK(naddr,
&r->src.addr.v.a.addr,
&r->src.addr.v.a.mask, saddr,
pd->af);
break;
}
break;
case PF_RDR: {
if (pf_map_addr(r->af, &r->rpool, saddr, naddr, NULL))
return (NULL);
if (r->rpool.proxy_port[1]) {
u_int32_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((u_int16_t)tmp_nport);
} else if (r->rpool.proxy_port[0])
*nport = htons(r->rpool.proxy_port[0]);
break;
}
default:
return (NULL);
break;
}
}
return (r);
}
int
pf_socket_lookup(uid_t *uid, gid_t *gid, int direction, sa_family_t af,
int proto, struct pf_pdesc *pd)
{
struct pf_addr *saddr, *daddr;
u_int16_t sport, dport;
struct inpcbtable *tb;
struct inpcb *inp;
*uid = UID_MAX;
*gid = GID_MAX;
switch (proto) {
case IPPROTO_TCP:
sport = pd->hdr.tcp->th_sport;
dport = pd->hdr.tcp->th_dport;
tb = &tcbtable;
break;
case IPPROTO_UDP:
sport = pd->hdr.udp->uh_sport;
dport = pd->hdr.udp->uh_dport;
tb = &udbtable;
break;
default:
return (0);
}
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(af) {
case AF_INET:
inp = in_pcbhashlookup(tb, saddr->v4, sport, daddr->v4, dport);
if (inp == NULL) {
inp = in_pcblookup(tb, &saddr->v4, sport, &daddr->v4,
dport, INPLOOKUP_WILDCARD);
if (inp == NULL)
return (0);
}
break;
#ifdef INET6
case AF_INET6:
inp = in6_pcbhashlookup(tb, &saddr->v6, sport, &daddr->v6,
dport);
if (inp == NULL) {
inp = in_pcblookup(tb, &saddr->v6, sport, &daddr->v6,
dport, INPLOOKUP_WILDCARD | INPLOOKUP_IPV6);
if (inp == NULL)
return (0);
}
break;
#endif /* INET6 */
default:
return (0);
}
*uid = inp->inp_socket->so_euid;
*gid = inp->inp_socket->so_egid;
return (1);
}
u_int8_t
pf_get_wscale(struct mbuf *m, int off, u_int16_t th_off, sa_family_t af)
{
int hlen;
u_int8_t hdr[60];
u_int8_t *opt, optlen;
u_int8_t wscale = 0;
hlen = th_off << 2; /* hlen <= sizeof(hdr) */
if (hlen <= sizeof(struct tcphdr))
return (0);
if (!pf_pull_hdr(m, off, hdr, hlen, NULL, NULL, af))
return (0);
opt = hdr + sizeof(struct tcphdr);
hlen -= sizeof(struct tcphdr);
while (hlen >= 3) {
switch (*opt) {
case TCPOPT_EOL:
case TCPOPT_NOP:
++opt;
--hlen;
break;
case TCPOPT_WINDOW:
wscale = opt[2];
if (wscale > TCP_MAX_WINSHIFT)
wscale = TCP_MAX_WINSHIFT;
wscale |= PF_WSCALE_FLAG;
/* fallthrough */
default:
optlen = opt[1];
if (optlen < 2)
optlen = 2;
hlen -= optlen;
opt += optlen;
}
}
return (wscale);
}
u_int16_t
pf_get_mss(struct mbuf *m, int off, u_int16_t th_off, sa_family_t af)
{
int hlen;
u_int8_t hdr[60];
u_int8_t *opt, optlen;
u_int16_t mss = 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);
/* fallthrough */
default:
optlen = opt[1];
if (optlen < 2)
optlen = 2;
hlen -= optlen;
opt += optlen;
}
}
return (mss);
}
u_int16_t
pf_calc_mss(struct pf_addr *addr, sa_family_t af, u_int16_t offer)
{
#ifdef INET
struct sockaddr_in *dst;
struct route ro;
#endif /* INET */
#ifdef INET6
struct sockaddr_in6 *dst6;
struct route_in6 ro6;
#endif /* INET6 */
struct rtentry *rt = NULL;
int hlen;
u_int16_t mss = 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;
rtalloc_noclone(&ro, NO_CLONING);
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;
rtalloc_noclone((struct route *)&ro6, NO_CLONING);
rt = ro6.ro_rt;
break;
#endif /* INET6 */
}
if (rt && rt->rt_ifp) {
mss = rt->rt_ifp->if_mtu - hlen - sizeof(struct tcphdr);
mss = max(tcp_mssdflt, mss);
RTFREE(rt);
}
mss = min(mss, offer);
mss = max(mss, 64); /* sanity - at least max opt space */
return (mss);
}
void
pf_set_rt_ifp(struct pf_state *s, struct pf_addr *saddr)
{
struct pf_rule *r = s->rule.ptr;
s->rt_ifp = NULL;
if (!r->rt || r->rt == PF_FASTROUTE)
return;
switch (s->af) {
#ifdef INET
case AF_INET:
pf_map_addr(AF_INET, &r->rpool, saddr,
&s->rt_addr, NULL);
s->rt_ifp = r->rpool.cur->ifp;
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
pf_map_addr(AF_INET6, &r->rpool, saddr,
&s->rt_addr, NULL);
s->rt_ifp = r->rpool.cur->ifp;
break;
#endif /* INET6 */
}
}
int
pf_test_tcp(struct pf_rule **rm, struct pf_state **sm, int direction,
struct ifnet *ifp, struct mbuf *m, int ipoff, int off, void *h,
struct pf_pdesc *pd, struct pf_rule **am, struct pf_ruleset **rsm)
{
struct pf_rule *nat = NULL, *rdr = NULL;
struct pf_addr *saddr = pd->src, *daddr = pd->dst;
struct pf_addr baddr, naddr;
struct tcphdr *th = pd->hdr.tcp;
u_int16_t bport, nport = 0;
sa_family_t af = pd->af;
int lookup = -1;
uid_t uid;
gid_t gid;
struct pf_rule *r, *a = NULL;
struct pf_ruleset *ruleset = NULL;
u_short reason;
int rewrite = 0;
struct pf_tag *pftag = NULL;
int tag = -1;
u_int16_t mss = tcp_mssdflt;
r = TAILQ_FIRST(pf_main_ruleset.rules[PF_RULESET_FILTER].active.ptr);
if (direction == PF_OUT) {
bport = nport = th->th_sport;
/* check outgoing packet for BINAT/NAT */
if ((nat = pf_get_translation(pd, m, off, PF_OUT, ifp,
saddr, th->th_sport, daddr, th->th_dport,
&naddr, &nport)) != NULL) {
PF_ACPY(&baddr, saddr, af);
pf_change_ap(saddr, &th->th_sport, pd->ip_sum,
&th->th_sum, &naddr, nport, 0, af);
rewrite++;
if (nat->natpass)
r = NULL;
}
} else {
bport = nport = th->th_dport;
/* check incoming packet for BINAT/RDR */
if ((rdr = pf_get_translation(pd, m, off, PF_IN, ifp, saddr,
th->th_sport, daddr, th->th_dport,
&naddr, &nport)) != NULL) {
PF_ACPY(&baddr, daddr, af);
pf_change_ap(daddr, &th->th_dport, pd->ip_sum,
&th->th_sum, &naddr, nport, 0, af);
rewrite++;
if (rdr->natpass)
r = NULL;
}
}
while (r != NULL) {
r->evaluations++;
if (r->ifp != NULL && ((r->ifp != ifp && !r->ifnot) ||
(r->ifp == ifp && 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 != IPPROTO_TCP)
r = r->skip[PF_SKIP_PROTO].ptr;
else if (PF_MISMATCHAW(&r->src.addr, saddr, af, r->src.not))
r = r->skip[PF_SKIP_SRC_ADDR].ptr;
else if (r->src.port_op && !pf_match_port(r->src.port_op,
r->src.port[0], r->src.port[1], th->th_sport))
r = r->skip[PF_SKIP_SRC_PORT].ptr;
else if (PF_MISMATCHAW(&r->dst.addr, daddr, af, r->dst.not))
r = r->skip[PF_SKIP_DST_ADDR].ptr;
else if (r->dst.port_op && !pf_match_port(r->dst.port_op,
r->dst.port[0], r->dst.port[1], th->th_dport))
r = r->skip[PF_SKIP_DST_PORT].ptr;
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 ((r->flagset & th->th_flags) != r->flags)
r = TAILQ_NEXT(r, entries);
else if (r->uid.op && (lookup != -1 || (lookup =
pf_socket_lookup(&uid, &gid, direction, af, IPPROTO_TCP,
pd), 1)) &&
!pf_match_uid(r->uid.op, r->uid.uid[0], r->uid.uid[1],
uid))
r = TAILQ_NEXT(r, entries);
else if (r->gid.op && (lookup != -1 || (lookup =
pf_socket_lookup(&uid, &gid, direction, af, IPPROTO_TCP,
pd), 1)) &&
!pf_match_gid(r->gid.op, r->gid.gid[0], r->gid.gid[1],
gid))
r = TAILQ_NEXT(r, entries);
else if (r->match_tag &&
!pf_match_tag(m, r, nat, rdr, pftag, &tag))
r = TAILQ_NEXT(r, entries);
else if (r->anchorname[0] && r->anchor == NULL)
r = TAILQ_NEXT(r, entries);
else if (r->os_fingerprint != PF_OSFP_ANY && !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->anchor == NULL) {
*rm = r;
*am = a;
*rsm = ruleset;
if ((*rm)->quick)
break;
r = TAILQ_NEXT(r, entries);
} else
PF_STEP_INTO_ANCHOR(r, a, ruleset,
PF_RULESET_FILTER);
}
if (r == NULL && a != NULL)
PF_STEP_OUT_OF_ANCHOR(r, a, ruleset,
PF_RULESET_FILTER);
}
r = *rm;
a = *am;
ruleset = *rsm;
r->packets++;
r->bytes += pd->tot_len;
if (a != NULL) {
a->packets++;
a->bytes += pd->tot_len;
}
REASON_SET(&reason, PFRES_MATCH);
if (r->log) {
if (rewrite)
m_copyback(m, off, sizeof(*th), th);
PFLOG_PACKET(ifp, h, m, af, direction, reason, r, a, ruleset);
}
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 (nat != NULL) {
pf_change_ap(saddr, &th->th_sport, pd->ip_sum,
&th->th_sum, &baddr, bport, 0, af);
rewrite++;
} else if (rdr != NULL) {
pf_change_ap(daddr, &th->th_dport, pd->ip_sum,
&th->th_sum, &baddr, bport, 0, af);
rewrite++;
}
if (((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;
if (th->th_flags & TH_SYN)
ack++;
if (th->th_flags & TH_FIN)
ack++;
pf_send_tcp(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);
} else if ((af == AF_INET) && r->return_icmp)
pf_send_icmp(m, r->return_icmp >> 8,
r->return_icmp & 255, af, r);
else if ((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)
return (PF_DROP);
if (pf_tag_packet(m, pftag, tag)) {
REASON_SET(&reason, PFRES_MEMORY);
return (PF_DROP);
}
if (r->keep_state || nat != NULL || rdr != NULL ||
(pd->flags & PFDESC_TCP_NORM)) {
/* create new state */
u_int16_t len;
struct pf_state *s = NULL;
len = pd->tot_len - off - (th->th_off << 2);
if (!r->max_states || r->states < r->max_states)
s = pool_get(&pf_state_pl, PR_NOWAIT);
if (s == NULL) {
REASON_SET(&reason, PFRES_MEMORY);
return (PF_DROP);
}
bzero(s, sizeof(*s));
r->states++;
if (a != NULL)
a->states++;
s->rule.ptr = r;
if (nat != NULL)
s->nat_rule.ptr = nat;
else
s->nat_rule.ptr = rdr;
if (s->nat_rule.ptr != NULL)
s->nat_rule.ptr->states++;
s->anchor.ptr = a;
s->allow_opts = r->allow_opts;
s->log = r->log & 2;
s->proto = IPPROTO_TCP;
s->direction = direction;
s->af = af;
if (direction == PF_OUT) {
PF_ACPY(&s->gwy.addr, saddr, af);
s->gwy.port = th->th_sport; /* sport */
PF_ACPY(&s->ext.addr, daddr, af);
s->ext.port = th->th_dport;
if (nat != NULL) {
PF_ACPY(&s->lan.addr, &baddr, af);
s->lan.port = bport;
} else {
PF_ACPY(&s->lan.addr, &s->gwy.addr, af);
s->lan.port = s->gwy.port;
}
} else {
PF_ACPY(&s->lan.addr, daddr, af);
s->lan.port = th->th_dport;
PF_ACPY(&s->ext.addr, saddr, af);
s->ext.port = th->th_sport;
if (rdr != NULL) {
PF_ACPY(&s->gwy.addr, &baddr, af);
s->gwy.port = bport;
} else {
PF_ACPY(&s->gwy.addr, &s->lan.addr, af);
s->gwy.port = s->lan.port;
}
}
s->src.seqlo = ntohl(th->th_seq);
s->src.seqhi = s->src.seqlo + len + 1;
if ((th->th_flags & (TH_SYN|TH_ACK)) == TH_SYN &&
r->keep_state == PF_STATE_MODULATE) {
/* Generate sequence number modulator */
while ((s->src.seqdiff = arc4random()) == 0)
;
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, 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->creation = time.tv_sec;
s->expire = time.tv_sec;
s->timeout = PFTM_TCP_FIRST_PACKET;
s->packets[0] = 1;
s->bytes[0] = pd->tot_len;
pf_set_rt_ifp(s, saddr);
if ((pd->flags & PFDESC_TCP_NORM) && pf_normalize_tcp_init(m,
off, pd, th, &s->src, &s->dst)) {
REASON_SET(&reason, PFRES_MEMORY);
pool_put(&pf_state_pl, s);
return (PF_DROP);
}
if ((pd->flags & PFDESC_TCP_NORM) && s->src.scrub &&
pf_normalize_tcp_stateful(m, off, pd, &reason, th, &s->src,
&s->dst, &rewrite)) {
pf_normalize_tcp_cleanup(s);
pool_put(&pf_state_pl, s);
return (PF_DROP);
}
if (pf_insert_state(s)) {
pf_normalize_tcp_cleanup(s);
REASON_SET(&reason, PFRES_MEMORY);
pool_put(&pf_state_pl, s);
return (PF_DROP);
} else
*sm = s;
if ((th->th_flags & (TH_SYN|TH_ACK)) == TH_SYN &&
r->keep_state == PF_STATE_SYNPROXY) {
s->src.state = PF_TCPS_PROXY_SRC;
if (nat != NULL)
pf_change_ap(saddr, &th->th_sport,
pd->ip_sum, &th->th_sum, &baddr,
bport, 0, af);
else if (rdr != NULL)
pf_change_ap(daddr, &th->th_dport,
pd->ip_sum, &th->th_sum, &baddr,
bport, 0, af);
s->src.seqhi = arc4random();
/* Find mss option */
mss = pf_get_mss(m, off, th->th_off, af);
mss = pf_calc_mss(saddr, af, mss);
mss = pf_calc_mss(daddr, af, mss);
s->src.mss = mss;
pf_send_tcp(r, af, daddr, saddr, th->th_dport,
th->th_sport, s->src.seqhi,
ntohl(th->th_seq) + 1, TH_SYN|TH_ACK, 0, s->src.mss, 0);
return (PF_SYNPROXY_DROP);
}
}
/* copy back packet headers if we performed NAT operations */
if (rewrite)
m_copyback(m, off, sizeof(*th), th);
return (PF_PASS);
}
int
pf_test_udp(struct pf_rule **rm, struct pf_state **sm, int direction,
struct ifnet *ifp, struct mbuf *m, int ipoff, int off, void *h,
struct pf_pdesc *pd, struct pf_rule **am, struct pf_ruleset **rsm)
{
struct pf_rule *nat = NULL, *rdr = NULL;
struct pf_addr *saddr = pd->src, *daddr = pd->dst;
struct pf_addr baddr, naddr;
struct udphdr *uh = pd->hdr.udp;
u_int16_t bport, nport = 0;
sa_family_t af = pd->af;
int lookup = -1;
uid_t uid;
gid_t gid;
struct pf_rule *r, *a = NULL;
struct pf_ruleset *ruleset = NULL;
u_short reason;
int rewrite = 0;
struct pf_tag *pftag = NULL;
int tag = -1;
r = TAILQ_FIRST(pf_main_ruleset.rules[PF_RULESET_FILTER].active.ptr);
if (direction == PF_OUT) {
bport = nport = uh->uh_sport;
/* check outgoing packet for BINAT/NAT */
if ((nat = pf_get_translation(pd, m, off, PF_OUT, ifp,
saddr, uh->uh_sport, daddr, uh->uh_dport,
&naddr, &nport)) != NULL) {
PF_ACPY(&baddr, saddr, af);
pf_change_ap(saddr, &uh->uh_sport, pd->ip_sum,
&uh->uh_sum, &naddr, nport, 1, af);
rewrite++;
if (nat->natpass)
r = NULL;
}
} else {
bport = nport = uh->uh_dport;
/* check incoming packet for BINAT/RDR */
if ((rdr = pf_get_translation(pd, m, off, PF_IN, ifp, saddr,
uh->uh_sport, daddr, uh->uh_dport, &naddr, &nport))
!= NULL) {
PF_ACPY(&baddr, daddr, af);
pf_change_ap(daddr, &uh->uh_dport, pd->ip_sum,
&uh->uh_sum, &naddr, nport, 1, af);
rewrite++;
if (rdr->natpass)
r = NULL;
}
}
while (r != NULL) {
r->evaluations++;
if (r->ifp != NULL && ((r->ifp != ifp && !r->ifnot) ||
(r->ifp == ifp && 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 != IPPROTO_UDP)
r = r->skip[PF_SKIP_PROTO].ptr;
else if (PF_MISMATCHAW(&r->src.addr, saddr, af, r->src.not))
r = r->skip[PF_SKIP_SRC_ADDR].ptr;
else if (r->src.port_op && !pf_match_port(r->src.port_op,
r->src.port[0], r->src.port[1], uh->uh_sport))
r = r->skip[PF_SKIP_SRC_PORT].ptr;
else if (PF_MISMATCHAW(&r->dst.addr, daddr, af, r->dst.not))
r = r->skip[PF_SKIP_DST_ADDR].ptr;
else if (r->dst.port_op && !pf_match_port(r->dst.port_op,
r->dst.port[0], r->dst.port[1], uh->uh_dport))
r = r->skip[PF_SKIP_DST_PORT].ptr;
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 (r->uid.op && (lookup != -1 || (lookup =
pf_socket_lookup(&uid, &gid, direction, af, IPPROTO_UDP,
pd), 1)) &&
!pf_match_uid(r->uid.op, r->uid.uid[0], r->uid.uid[1],
uid))
r = TAILQ_NEXT(r, entries);
else if (r->gid.op && (lookup != -1 || (lookup =
pf_socket_lookup(&uid, &gid, direction, af, IPPROTO_UDP,
pd), 1)) &&
!pf_match_gid(r->gid.op, r->gid.gid[0], r->gid.gid[1],
gid))
r = TAILQ_NEXT(r, entries);
else if (r->match_tag &&
!pf_match_tag(m, r, nat, rdr, pftag, &tag))
r = TAILQ_NEXT(r, entries);
else if (r->anchorname[0] && r->anchor == NULL)
r = TAILQ_NEXT(r, entries);
else if (r->os_fingerprint != PF_OSFP_ANY)
r = TAILQ_NEXT(r, entries);
else {
if (r->tag)
tag = r->tag;
if (r->anchor == NULL) {
*rm = r;
*am = a;
*rsm = ruleset;
if ((*rm)->quick)
break;
r = TAILQ_NEXT(r, entries);
} else
PF_STEP_INTO_ANCHOR(r, a, ruleset,
PF_RULESET_FILTER);
}
if (r == NULL && a != NULL)
PF_STEP_OUT_OF_ANCHOR(r, a, ruleset,
PF_RULESET_FILTER);
}
r = *rm;
a = *am;
ruleset = *rsm;
r->packets++;
r->bytes += pd->tot_len;
if (a != NULL) {
a->packets++;
a->bytes += pd->tot_len;
}
REASON_SET(&reason, PFRES_MATCH);
if (r->log) {
if (rewrite)
m_copyback(m, off, sizeof(*uh), uh);
PFLOG_PACKET(ifp, h, m, af, direction, reason, r, a, ruleset);
}
if ((r->action == PF_DROP) &&
((r->rule_flag & PFRULE_RETURNICMP) ||
(r->rule_flag & PFRULE_RETURN))) {
/* undo NAT changes, if they have taken place */
if (nat != NULL) {
pf_change_ap(saddr, &uh->uh_sport, pd->ip_sum,
&uh->uh_sum, &baddr, bport, 1, af);
rewrite++;
} else if (rdr != NULL) {
pf_change_ap(daddr, &uh->uh_dport, pd->ip_sum,
&uh->uh_sum, &baddr, bport, 1, af);
rewrite++;
}
if ((af == AF_INET) && r->return_icmp)
pf_send_icmp(m, r->return_icmp >> 8,
r->return_icmp & 255, af, r);
else if ((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)
return (PF_DROP);
if (pf_tag_packet(m, pftag, tag)) {
REASON_SET(&reason, PFRES_MEMORY);
return (PF_DROP);
}
if (r->keep_state || nat != NULL || rdr != NULL) {
/* create new state */
struct pf_state *s = NULL;
if (!r->max_states || r->states < r->max_states)
s = pool_get(&pf_state_pl, PR_NOWAIT);
if (s == NULL) {
REASON_SET(&reason, PFRES_MEMORY);
return (PF_DROP);
}
bzero(s, sizeof(*s));
r->states++;
if (a != NULL)
a->states++;
s->rule.ptr = r;
if (nat != NULL)
s->nat_rule.ptr = nat;
else
s->nat_rule.ptr = rdr;
if (s->nat_rule.ptr != NULL)
s->nat_rule.ptr->states++;
s->anchor.ptr = a;
s->allow_opts = r->allow_opts;
s->log = r->log & 2;
s->proto = IPPROTO_UDP;
s->direction = direction;
s->af = af;
if (direction == PF_OUT) {
PF_ACPY(&s->gwy.addr, saddr, af);
s->gwy.port = uh->uh_sport;
PF_ACPY(&s->ext.addr, daddr, af);
s->ext.port = uh->uh_dport;
if (nat != NULL) {
PF_ACPY(&s->lan.addr, &baddr, af);
s->lan.port = bport;
} else {
PF_ACPY(&s->lan.addr, &s->gwy.addr, af);
s->lan.port = s->gwy.port;
}
} else {
PF_ACPY(&s->lan.addr, daddr, af);
s->lan.port = uh->uh_dport;
PF_ACPY(&s->ext.addr, saddr, af);
s->ext.port = uh->uh_sport;
if (rdr != NULL) {
PF_ACPY(&s->gwy.addr, &baddr, af);
s->gwy.port = bport;
} else {
PF_ACPY(&s->gwy.addr, &s->lan.addr, af);
s->gwy.port = s->lan.port;
}
}
s->src.state = PFUDPS_SINGLE;
s->dst.state = PFUDPS_NO_TRAFFIC;
s->creation = time.tv_sec;
s->expire = time.tv_sec;
s->timeout = PFTM_UDP_FIRST_PACKET;
s->packets[0] = 1;
s->bytes[0] = pd->tot_len;
pf_set_rt_ifp(s, saddr);
if (pf_insert_state(s)) {
REASON_SET(&reason, PFRES_MEMORY);
pool_put(&pf_state_pl, s);
return (PF_DROP);
} else
*sm = s;
}
/* copy back packet headers if we performed NAT operations */
if (rewrite)
m_copyback(m, off, sizeof(*uh), uh);
return (PF_PASS);
}
int
pf_test_icmp(struct pf_rule **rm, struct pf_state **sm, int direction,
struct ifnet *ifp, struct mbuf *m, int ipoff, int off, void *h,
struct pf_pdesc *pd, struct pf_rule **am, struct pf_ruleset **rsm)
{
struct pf_rule *nat = NULL, *rdr = NULL;
struct pf_addr *saddr = pd->src, *daddr = pd->dst;
struct pf_addr baddr, naddr;
struct pf_rule *r, *a = NULL;
struct pf_ruleset *ruleset = NULL;
u_short reason;
u_int16_t icmpid;
sa_family_t af = pd->af;
u_int8_t icmptype, icmpcode;
int state_icmp = 0;
struct pf_tag *pftag = NULL;
int tag = -1;
#ifdef INET6
int rewrite = 0;
#endif /* INET6 */
switch (pd->proto) {
#ifdef INET
case IPPROTO_ICMP:
icmptype = pd->hdr.icmp->icmp_type;
icmpcode = pd->hdr.icmp->icmp_code;
icmpid = pd->hdr.icmp->icmp_id;
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;
icmpcode = pd->hdr.icmp6->icmp6_code;
icmpid = pd->hdr.icmp6->icmp6_id;
if (icmptype == ICMP6_DST_UNREACH ||
icmptype == ICMP6_PACKET_TOO_BIG ||
icmptype == ICMP6_TIME_EXCEEDED ||
icmptype == ICMP6_PARAM_PROB)
state_icmp++;
break;
#endif /* INET6 */
}
r = TAILQ_FIRST(pf_main_ruleset.rules[PF_RULESET_FILTER].active.ptr);
if (direction == PF_OUT) {
/* check outgoing packet for BINAT/NAT */
if ((nat = pf_get_translation(pd, m, off, PF_OUT, ifp, saddr, 0,
daddr, 0, &naddr, NULL)) != NULL) {
PF_ACPY(&baddr, saddr, af);
switch (af) {
#ifdef INET
case AF_INET:
pf_change_a(&saddr->v4.s_addr, pd->ip_sum,
naddr.v4.s_addr, 0);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
pf_change_a6(saddr, &pd->hdr.icmp6->icmp6_cksum,
&naddr, 0);
rewrite++;
break;
#endif /* INET6 */
}
if (nat->natpass)
r = NULL;
}
} else {
/* check incoming packet for BINAT/RDR */
if ((rdr = pf_get_translation(pd, m, off, PF_IN, ifp, saddr, 0,
daddr, 0, &naddr, NULL)) != NULL) {
PF_ACPY(&baddr, daddr, af);
switch (af) {
#ifdef INET
case AF_INET:
pf_change_a(&daddr->v4.s_addr,
pd->ip_sum, naddr.v4.s_addr, 0);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
pf_change_a6(daddr, &pd->hdr.icmp6->icmp6_cksum,
&naddr, 0);
rewrite++;
break;
#endif /* INET6 */
}
if (rdr->natpass)
r = NULL;
}
}
while (r != NULL) {
r->evaluations++;
if (r->ifp != NULL && ((r->ifp != ifp && !r->ifnot) ||
(r->ifp == ifp && 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.not))
r = r->skip[PF_SKIP_SRC_ADDR].ptr;
else if (PF_MISMATCHAW(&r->dst.addr, daddr, af, r->dst.not))
r = r->skip[PF_SKIP_DST_ADDR].ptr;
else if (r->type && r->type != icmptype + 1)
r = TAILQ_NEXT(r, entries);
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 (r->match_tag &&
!pf_match_tag(m, r, nat, rdr, pftag, &tag))
r = TAILQ_NEXT(r, entries);
else if (r->anchorname[0] && r->anchor == NULL)
r = TAILQ_NEXT(r, entries);
else if (r->os_fingerprint != PF_OSFP_ANY)
r = TAILQ_NEXT(r, entries);
else {
if (r->tag)
tag = r->tag;
if (r->anchor == NULL) {
*rm = r;
*am = a;
*rsm = ruleset;
if ((*rm)->quick)
break;
r = TAILQ_NEXT(r, entries);
} else
PF_STEP_INTO_ANCHOR(r, a, ruleset,
PF_RULESET_FILTER);
}
if (r == NULL && a != NULL)
PF_STEP_OUT_OF_ANCHOR(r, a, ruleset,
PF_RULESET_FILTER);
}
r = *rm;
a = *am;
ruleset = *rsm;
r->packets++;
r->bytes += pd->tot_len;
if (a != NULL) {
a->packets++;
a->bytes += pd->tot_len;
}
REASON_SET(&reason, PFRES_MATCH);
if (r->log) {
#ifdef INET6
if (rewrite)
m_copyback(m, off, sizeof(struct icmp6_hdr),
pd->hdr.icmp6);
#endif /* INET6 */
PFLOG_PACKET(ifp, h, m, af, direction, reason, r, a, ruleset);
}
if (r->action != PF_PASS)
return (PF_DROP);
if (pf_tag_packet(m, pftag, tag)) {
REASON_SET(&reason, PFRES_MEMORY);
return (PF_DROP);
}
if (!state_icmp && (r->keep_state ||
nat != NULL || rdr != NULL)) {
/* create new state */
struct pf_state *s = NULL;
if (!r->max_states || r->states < r->max_states)
s = pool_get(&pf_state_pl, PR_NOWAIT);
if (s == NULL) {
REASON_SET(&reason, PFRES_MEMORY);
return (PF_DROP);
}
bzero(s, sizeof(*s));
r->states++;
if (a != NULL)
a->states++;
s->rule.ptr = r;
if (nat != NULL)
s->nat_rule.ptr = nat;
else
s->nat_rule.ptr = rdr;
if (s->nat_rule.ptr != NULL)
s->nat_rule.ptr->states++;
s->anchor.ptr = a;
s->allow_opts = r->allow_opts;
s->log = r->log & 2;
s->proto = pd->proto;
s->direction = direction;
s->af = af;
if (direction == PF_OUT) {
PF_ACPY(&s->gwy.addr, saddr, af);
s->gwy.port = icmpid;
PF_ACPY(&s->ext.addr, daddr, af);
s->ext.port = icmpid;
if (nat != NULL)
PF_ACPY(&s->lan.addr, &baddr, af);
else
PF_ACPY(&s->lan.addr, &s->gwy.addr, af);
s->lan.port = icmpid;
} else {
PF_ACPY(&s->lan.addr, daddr, af);
s->lan.port = icmpid;
PF_ACPY(&s->ext.addr, saddr, af);
s->ext.port = icmpid;
if (rdr != NULL)
PF_ACPY(&s->gwy.addr, &baddr, af);
else
PF_ACPY(&s->gwy.addr, &s->lan.addr, af);
s->gwy.port = icmpid;
}
s->creation = time.tv_sec;
s->expire = time.tv_sec;
s->timeout = PFTM_ICMP_FIRST_PACKET;
s->packets[0] = 1;
s->bytes[0] = pd->tot_len;
pf_set_rt_ifp(s, saddr);
if (pf_insert_state(s)) {
REASON_SET(&reason, PFRES_MEMORY);
pool_put(&pf_state_pl, s);
return (PF_DROP);
} else
*sm = s;
}
#ifdef INET6
/* copy back packet headers if we performed IPv6 NAT operations */
if (rewrite)
m_copyback(m, off, sizeof(struct icmp6_hdr),
pd->hdr.icmp6);
#endif /* INET6 */
return (PF_PASS);
}
int
pf_test_other(struct pf_rule **rm, struct pf_state **sm, int direction,
struct ifnet *ifp, struct mbuf *m, int off, void *h, struct pf_pdesc *pd,
struct pf_rule **am, struct pf_ruleset **rsm)
{
struct pf_rule *nat = NULL, *rdr = NULL;
struct pf_rule *r, *a = NULL;
struct pf_ruleset *ruleset = NULL;
struct pf_addr *saddr = pd->src, *daddr = pd->dst;
struct pf_addr baddr, naddr;
sa_family_t af = pd->af;
u_short reason;
struct pf_tag *pftag = NULL;
int tag = -1;
r = TAILQ_FIRST(pf_main_ruleset.rules[PF_RULESET_FILTER].active.ptr);
if (direction == PF_OUT) {
/* check outgoing packet for BINAT/NAT */
if ((nat = pf_get_translation(pd, m, off, PF_OUT, ifp, saddr, 0,
daddr, 0, &naddr, NULL)) != NULL) {
PF_ACPY(&baddr, saddr, af);
switch (af) {
#ifdef INET
case AF_INET:
pf_change_a(&saddr->v4.s_addr, pd->ip_sum,
naddr.v4.s_addr, 0);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
PF_ACPY(saddr, &naddr, af);
break;
#endif /* INET6 */
}
if (nat->natpass)
r = NULL;
}
} else {
/* check incoming packet for BINAT/RDR */
if ((rdr = pf_get_translation(pd, m, off, PF_IN, ifp, saddr, 0,
daddr, 0, &naddr, NULL)) != NULL) {
PF_ACPY(&baddr, daddr, af);
switch (af) {
#ifdef INET
case AF_INET:
pf_change_a(&daddr->v4.s_addr,
pd->ip_sum, naddr.v4.s_addr, 0);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
PF_ACPY(daddr, &naddr, af);
break;
#endif /* INET6 */
}
if (rdr->natpass)
r = NULL;
}
}
while (r != NULL) {
r->evaluations++;
if (r->ifp != NULL && ((r->ifp != ifp && !r->ifnot) ||
(r->ifp == ifp && 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.not))
r = r->skip[PF_SKIP_SRC_ADDR].ptr;
else if (PF_MISMATCHAW(&r->dst.addr, pd->dst, af, r->dst.not))
r = r->skip[PF_SKIP_DST_ADDR].ptr;
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 (r->match_tag &&
!pf_match_tag(m, r, nat, rdr, pftag, &tag))
r = TAILQ_NEXT(r, entries);
else if (r->anchorname[0] && r->anchor == NULL)
r = TAILQ_NEXT(r, entries);
else if (r->os_fingerprint != PF_OSFP_ANY)
r = TAILQ_NEXT(r, entries);
else {
if (r->tag)
tag = r->tag;
if (r->anchor == NULL) {
*rm = r;
*am = a;
*rsm = ruleset;
if ((*rm)->quick)
break;
r = TAILQ_NEXT(r, entries);
} else
PF_STEP_INTO_ANCHOR(r, a, ruleset,
PF_RULESET_FILTER);
}
if (r == NULL && a != NULL)
PF_STEP_OUT_OF_ANCHOR(r, a, ruleset,
PF_RULESET_FILTER);
}
r = *rm;
a = *am;
ruleset = *rsm;
r->packets++;
r->bytes += pd->tot_len;
if (a != NULL) {
a->packets++;
a->bytes += pd->tot_len;
}
REASON_SET(&reason, PFRES_MATCH);
if (r->log)
PFLOG_PACKET(ifp, h, m, af, direction, reason, r, a, ruleset);
if ((r->action == PF_DROP) &&
((r->rule_flag & PFRULE_RETURNICMP) ||
(r->rule_flag & PFRULE_RETURN))) {
struct pf_addr *a = NULL;
if (nat != NULL)
a = saddr;
else if (rdr != NULL)
a = daddr;
if (a != NULL) {
switch (af) {
#ifdef INET
case AF_INET:
pf_change_a(&a->v4.s_addr, pd->ip_sum,
baddr.v4.s_addr, 0);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
PF_ACPY(a, &baddr, af);
break;
#endif /* INET6 */
}
}
if ((af == AF_INET) && r->return_icmp)
pf_send_icmp(m, r->return_icmp >> 8,
r->return_icmp & 255, af, r);
else if ((af == AF_INET6) && r->return_icmp6)
pf_send_icmp(m, r->return_icmp6 >> 8,
r->return_icmp6 & 255, af, r);
}
if (r->action != PF_PASS)
return (PF_DROP);
if (pf_tag_packet(m, pftag, tag)) {
REASON_SET(&reason, PFRES_MEMORY);
return (PF_DROP);
}
if (r->keep_state || nat != NULL || rdr != NULL) {
/* create new state */
struct pf_state *s = NULL;
if (!r->max_states || r->states < r->max_states)
s = pool_get(&pf_state_pl, PR_NOWAIT);
if (s == NULL) {
REASON_SET(&reason, PFRES_MEMORY);
return (PF_DROP);
}
bzero(s, sizeof(*s));
r->states++;
if (a != NULL)
a->states++;
s->rule.ptr = r;
if (nat != NULL)
s->nat_rule.ptr = nat;
else
s->nat_rule.ptr = rdr;
if (s->nat_rule.ptr != NULL)
s->nat_rule.ptr->states++;
s->anchor.ptr = a;
s->allow_opts = r->allow_opts;
s->log = r->log & 2;
s->proto = pd->proto;
s->direction = direction;
s->af = af;
if (direction == PF_OUT) {
PF_ACPY(&s->gwy.addr, saddr, af);
PF_ACPY(&s->ext.addr, daddr, af);
if (nat != NULL)
PF_ACPY(&s->lan.addr, &baddr, af);
else
PF_ACPY(&s->lan.addr, &s->gwy.addr, af);
} else {
PF_ACPY(&s->lan.addr, daddr, af);
PF_ACPY(&s->ext.addr, saddr, af);
if (rdr != NULL)
PF_ACPY(&s->gwy.addr, &baddr, af);
else
PF_ACPY(&s->gwy.addr, &s->lan.addr, af);
}
s->src.state = PFOTHERS_SINGLE;
s->dst.state = PFOTHERS_NO_TRAFFIC;
s->creation = time.tv_sec;
s->expire = time.tv_sec;
s->timeout = PFTM_OTHER_FIRST_PACKET;
s->packets[0] = 1;
s->bytes[0] = pd->tot_len;
pf_set_rt_ifp(s, saddr);
if (pf_insert_state(s)) {
REASON_SET(&reason, PFRES_MEMORY);
if (r->log)
PFLOG_PACKET(ifp, h, m, af, direction, reason,
r, a, ruleset);
pool_put(&pf_state_pl, s);
return (PF_DROP);
} else
*sm = s;
}
return (PF_PASS);
}
int
pf_test_fragment(struct pf_rule **rm, int direction, struct ifnet *ifp,
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;
struct pf_tag *pftag = NULL;
int tag = -1;
r = TAILQ_FIRST(pf_main_ruleset.rules[PF_RULESET_FILTER].active.ptr);
while (r != NULL) {
r->evaluations++;
if (r->ifp != NULL && ((r->ifp != ifp && !r->ifnot) ||
(r->ifp == ifp && 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.not))
r = r->skip[PF_SKIP_SRC_ADDR].ptr;
else if (PF_MISMATCHAW(&r->dst.addr, pd->dst, af, r->dst.not))
r = r->skip[PF_SKIP_DST_ADDR].ptr;
else if (r->tos && !(r->tos & pd->tos))
r = TAILQ_NEXT(r, entries);
else if (r->src.port_op || r->dst.port_op ||
r->flagset || r->type || r->code ||
r->os_fingerprint != PF_OSFP_ANY)
r = TAILQ_NEXT(r, entries);
else if (r->match_tag &&
!pf_match_tag(m, r, NULL, NULL, pftag, &tag))
r = TAILQ_NEXT(r, entries);
else if (r->anchorname[0] && r->anchor == NULL)
r = TAILQ_NEXT(r, entries);
else {
if (r->anchor == NULL) {
*rm = r;
*am = a;
*rsm = ruleset;
if ((*rm)->quick)
break;
r = TAILQ_NEXT(r, entries);
} else
PF_STEP_INTO_ANCHOR(r, a, ruleset,
PF_RULESET_FILTER);
}
if (r == NULL && a != NULL)
PF_STEP_OUT_OF_ANCHOR(r, a, ruleset,
PF_RULESET_FILTER);
}
r = *rm;
a = *am;
ruleset = *rsm;
r->packets++;
r->bytes += pd->tot_len;
if (a != NULL) {
a->packets++;
a->bytes += pd->tot_len;
}
REASON_SET(&reason, PFRES_MATCH);
if (r->log)
PFLOG_PACKET(ifp, h, m, af, direction, reason, r, a, ruleset);
if (r->action != PF_PASS)
return (PF_DROP);
if (pf_tag_packet(m, pftag, tag)) {
REASON_SET(&reason, PFRES_MEMORY);
return (PF_DROP);
}
return (PF_PASS);
}
int
pf_test_state_tcp(struct pf_state **state, int direction, struct ifnet *ifp,
struct mbuf *m, int ipoff, int off, void *h, struct pf_pdesc *pd,
u_short *reason)
{
struct pf_tree_node key;
struct tcphdr *th = pd->hdr.tcp;
u_int16_t win = ntohs(th->th_win);
u_int32_t ack, end, seq;
u_int8_t sws, dws;
int ackskew, dirndx;
int copyback = 0;
struct pf_state_peer *src, *dst;
key.af = pd->af;
key.proto = IPPROTO_TCP;
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;
STATE_LOOKUP();
if (direction == (*state)->direction) {
src = &(*state)->src;
dst = &(*state)->dst;
dirndx = 0;
} else {
src = &(*state)->dst;
dst = &(*state)->src;
dirndx = 1;
}
if ((*state)->src.state == PF_TCPS_PROXY_SRC) {
if (direction != (*state)->direction)
return (PF_SYNPROXY_DROP);
if (th->th_flags & TH_SYN) {
if (ntohl(th->th_seq) != (*state)->src.seqlo)
return (PF_DROP);
pf_send_tcp((*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);
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))
return (PF_DROP);
else
(*state)->src.state = PF_TCPS_PROXY_DST;
}
if ((*state)->src.state == PF_TCPS_PROXY_DST) {
struct pf_state_host *src, *dst;
if (direction == PF_OUT) {
src = &(*state)->gwy;
dst = &(*state)->ext;
} else {
src = &(*state)->ext;
dst = &(*state)->lan;
}
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))
return (PF_DROP);
(*state)->src.max_win = MAX(ntohs(th->th_win), 1);
if ((*state)->dst.seqhi == 1)
(*state)->dst.seqhi = arc4random();
pf_send_tcp((*state)->rule.ptr, pd->af, &src->addr,
&dst->addr, src->port, dst->port,
(*state)->dst.seqhi, 0, TH_SYN, 0, (*state)->src.mss, 0);
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))
return (PF_DROP);
else {
(*state)->dst.max_win = MAX(ntohs(th->th_win), 1);
(*state)->dst.seqlo = ntohl(th->th_seq);
pf_send_tcp((*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);
pf_send_tcp((*state)->rule.ptr, pd->af, &src->addr,
&dst->addr, src->port, dst->port,
(*state)->src.seqhi + 1, (*state)->src.seqlo + 1,
TH_ACK, (*state)->dst.max_win, 0, 0);
(*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)->src.max_win;
(*state)->dst.seqhi = (*state)->dst.seqlo +
(*state)->dst.max_win;
(*state)->src.wscale = (*state)->dst.wscale = 0;
(*state)->src.state = (*state)->dst.state =
TCPS_ESTABLISHED;
return (PF_SYNPROXY_DROP);
}
}
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
*/
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) {
while ((src->seqdiff = arc4random()) == 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;
#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 */
(*state)->packets[dirndx]++;
(*state)->bytes[dirndx] += pd->tot_len;
/* 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;
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.tv_sec;
if (src->state >= TCPS_FIN_WAIT_2 &&
dst->state >= TCPS_FIN_WAIT_2)
(*state)->timeout = PFTM_TCP_CLOSED;
else if (src->state >= TCPS_FIN_WAIT_2 ||
dst->state >= TCPS_FIN_WAIT_2)
(*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 (pf_status.debug >= PF_DEBUG_MISC) {
printf("pf: loose state match: ");
pf_print_state(*state);
pf_print_flags(th->th_flags);
printf(" seq=%u ack=%u len=%u ackskew=%d pkts=%d:%d\n",
seq, ack, pd->p_len, ackskew,
(*state)->packets[0], (*state)->packets[1]);
}
(*state)->packets[dirndx]++;
(*state)->bytes[dirndx] += pd->tot_len;
/* 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)) {
u_int32_t ack = ntohl(th->th_seq) + pd->p_len;
if (th->th_flags & TH_SYN)
ack++;
if (th->th_flags & TH_FIN)
ack++;
pf_send_tcp((*state)->rule.ptr, pd->af,
pd->dst, pd->src, th->th_dport,
th->th_sport, ntohl(th->th_ack), ack,
TH_RST|TH_ACK, 0, 0,
(*state)->rule.ptr->return_ttl);
}
src->seqlo = 0;
src->seqhi = 1;
src->max_win = 1;
} else if (pf_status.debug >= PF_DEBUG_MISC) {
printf("pf: BAD state: ");
pf_print_state(*state);
pf_print_flags(th->th_flags);
printf(" seq=%u ack=%u len=%u ackskew=%d pkts=%d:%d "
"dir=%s,%s\n", seq, ack, pd->p_len, ackskew,
(*state)->packets[0], (*state)->packets[1],
direction == PF_IN ? "in" : "out",
direction == (*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');
}
return (PF_DROP);
}
if (dst->scrub || src->scrub) {
if (pf_normalize_tcp_stateful(m, off, pd, reason, th, src, dst,
&copyback))
return (PF_DROP);
}
/* Any packets which have gotten here are to be passed */
/* translate source/destination address, if necessary */
if (STATE_TRANSLATE(*state)) {
if (direction == PF_OUT)
pf_change_ap(pd->src, &th->th_sport, pd->ip_sum,
&th->th_sum, &(*state)->gwy.addr,
(*state)->gwy.port, 0, pd->af);
else
pf_change_ap(pd->dst, &th->th_dport, pd->ip_sum,
&th->th_sum, &(*state)->lan.addr,
(*state)->lan.port, 0, pd->af);
m_copyback(m, off, sizeof(*th), th);
} else if (copyback) {
/* Copyback sequence modulation or stateful scrub changes */
m_copyback(m, off, sizeof(*th), th);
}
(*state)->rule.ptr->packets++;
(*state)->rule.ptr->bytes += pd->tot_len;
if ((*state)->nat_rule.ptr != NULL) {
(*state)->nat_rule.ptr->packets++;
(*state)->nat_rule.ptr->bytes += pd->tot_len;
}
if ((*state)->anchor.ptr != NULL) {
(*state)->anchor.ptr->packets++;
(*state)->anchor.ptr->bytes += pd->tot_len;
}
return (PF_PASS);
}
int
pf_test_state_udp(struct pf_state **state, int direction, struct ifnet *ifp,
struct mbuf *m, int ipoff, int off, void *h, struct pf_pdesc *pd)
{
struct pf_state_peer *src, *dst;
struct pf_tree_node key;
struct udphdr *uh = pd->hdr.udp;
int dirndx;
key.af = pd->af;
key.proto = IPPROTO_UDP;
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;
STATE_LOOKUP();
if (direction == (*state)->direction) {
src = &(*state)->src;
dst = &(*state)->dst;
dirndx = 0;
} else {
src = &(*state)->dst;
dst = &(*state)->src;
dirndx = 1;
}
(*state)->packets[dirndx]++;
(*state)->bytes[dirndx] += pd->tot_len;
/* 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.tv_sec;
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_TRANSLATE(*state)) {
if (direction == PF_OUT)
pf_change_ap(pd->src, &uh->uh_sport, pd->ip_sum,
&uh->uh_sum, &(*state)->gwy.addr,
(*state)->gwy.port, 1, pd->af);
else
pf_change_ap(pd->dst, &uh->uh_dport, pd->ip_sum,
&uh->uh_sum, &(*state)->lan.addr,
(*state)->lan.port, 1, pd->af);
m_copyback(m, off, sizeof(*uh), uh);
}
(*state)->rule.ptr->packets++;
(*state)->rule.ptr->bytes += pd->tot_len;
if ((*state)->nat_rule.ptr != NULL) {
(*state)->nat_rule.ptr->packets++;
(*state)->nat_rule.ptr->bytes += pd->tot_len;
}
if ((*state)->anchor.ptr != NULL) {
(*state)->anchor.ptr->packets++;
(*state)->anchor.ptr->bytes += pd->tot_len;
}
return (PF_PASS);
}
int
pf_test_state_icmp(struct pf_state **state, int direction, struct ifnet *ifp,
struct mbuf *m, int ipoff, int off, void *h, struct pf_pdesc *pd)
{
struct pf_addr *saddr = pd->src, *daddr = pd->dst;
u_int16_t icmpid, *icmpsum;
u_int8_t icmptype;
int state_icmp = 0, dirndx;
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.
*/
struct pf_tree_node key;
key.af = pd->af;
key.proto = pd->proto;
PF_ACPY(&key.addr[0], saddr, key.af);
PF_ACPY(&key.addr[1], daddr, key.af);
key.port[0] = icmpid;
key.port[1] = icmpid;
STATE_LOOKUP();
dirndx = (direction == (*state)->direction) ? 0 : 1;
(*state)->packets[dirndx]++;
(*state)->bytes[dirndx] += pd->tot_len;
(*state)->expire = time.tv_sec;
(*state)->timeout = PFTM_ICMP_ERROR_REPLY;
/* translate source/destination address, if necessary */
if (PF_ANEQ(&(*state)->lan.addr, &(*state)->gwy.addr, pd->af)) {
if (direction == PF_OUT) {
switch (pd->af) {
#ifdef INET
case AF_INET:
pf_change_a(&saddr->v4.s_addr,
pd->ip_sum,
(*state)->gwy.addr.v4.s_addr, 0);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
pf_change_a6(saddr,
&pd->hdr.icmp6->icmp6_cksum,
&(*state)->gwy.addr, 0);
m_copyback(m, off,
sizeof(struct icmp6_hdr),
pd->hdr.icmp6);
break;
#endif /* INET6 */
}
} else {
switch (pd->af) {
#ifdef INET
case AF_INET:
pf_change_a(&daddr->v4.s_addr,
pd->ip_sum,
(*state)->lan.addr.v4.s_addr, 0);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
pf_change_a6(daddr,
&pd->hdr.icmp6->icmp6_cksum,
&(*state)->lan.addr, 0);
m_copyback(m, off,
sizeof(struct icmp6_hdr),
pd->hdr.icmp6);
break;
#endif /* INET6 */
}
}
}
return (PF_PASS);
} else {
/*
* ICMP error message in response to a TCP/UDP packet.
* Extract the inner TCP/UDP header and search for that state.
*/
struct pf_pdesc pd2;
#ifdef INET
struct ip h2;
#endif /* INET */
#ifdef INET6
struct ip6_hdr h2_6;
int terminal = 0;
#endif /* INET6 */
int ipoff2;
int off2;
pd2.af = pd->af;
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, NULL, 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))
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, NULL, 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
*/
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, NULL, 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_tree_node key;
struct pf_state_peer *src, *dst;
u_int8_t dws;
/*
* 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, NULL, 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[0], pd2.dst, pd2.af);
key.port[0] = th.th_dport;
PF_ACPY(&key.addr[1], pd2.src, pd2.af);
key.port[1] = th.th_sport;
STATE_LOOKUP();
if (direction == (*state)->direction) {
src = &(*state)->dst;
dst = &(*state)->src;
} else {
src = &(*state)->src;
dst = &(*state)->dst;
}
if (src->wscale && dst->wscale && !(th.th_flags & TH_SYN))
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, &th.th_sum,
htonl(seq), 0);
if (!SEQ_GEQ(src->seqhi, seq) ||
!SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws))) {
if (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);
}
return (PF_DROP);
}
if (STATE_TRANSLATE(*state)) {
if (direction == PF_IN) {
pf_change_icmp(pd2.src, &th.th_sport,
saddr, &(*state)->lan.addr,
(*state)->lan.port, NULL,
pd2.ip_sum, icmpsum,
pd->ip_sum, 0, pd2.af);
} else {
pf_change_icmp(pd2.dst, &th.th_dport,
saddr, &(*state)->gwy.addr,
(*state)->gwy.port, 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,
pd->hdr.icmp);
m_copyback(m, ipoff2, sizeof(h2),
&h2);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
m_copyback(m, off,
sizeof(struct icmp6_hdr),
pd->hdr.icmp6);
m_copyback(m, ipoff2, sizeof(h2_6),
&h2_6);
break;
#endif /* INET6 */
}
m_copyback(m, off2, 8, &th);
} else if (src->seqdiff) {
m_copyback(m, off2, 8, &th);
}
return (PF_PASS);
break;
}
case IPPROTO_UDP: {
struct udphdr uh;
struct pf_tree_node key;
if (!pf_pull_hdr(m, off2, &uh, sizeof(uh),
NULL, NULL, 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[0], pd2.dst, pd2.af);
key.port[0] = uh.uh_dport;
PF_ACPY(&key.addr[1], pd2.src, pd2.af);
key.port[1] = uh.uh_sport;
STATE_LOOKUP();
if (STATE_TRANSLATE(*state)) {
if (direction == PF_IN) {
pf_change_icmp(pd2.src, &uh.uh_sport,
daddr, &(*state)->lan.addr,
(*state)->lan.port, &uh.uh_sum,
pd2.ip_sum, icmpsum,
pd->ip_sum, 1, pd2.af);
} else {
pf_change_icmp(pd2.dst, &uh.uh_dport,
saddr, &(*state)->gwy.addr,
(*state)->gwy.port, &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,
pd->hdr.icmp);
m_copyback(m, ipoff2, sizeof(h2), &h2);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
m_copyback(m, off,
sizeof(struct icmp6_hdr),
pd->hdr.icmp6);
m_copyback(m, ipoff2, sizeof(h2_6),
&h2_6);
break;
#endif /* INET6 */
}
m_copyback(m, off2, sizeof(uh), &uh);
}
return (PF_PASS);
break;
}
#ifdef INET
case IPPROTO_ICMP: {
struct icmp iih;
struct pf_tree_node key;
if (!pf_pull_hdr(m, off2, &iih, ICMP_MINLEN,
NULL, NULL, 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[0], pd2.dst, pd2.af);
key.port[0] = iih.icmp_id;
PF_ACPY(&key.addr[1], pd2.src, pd2.af);
key.port[1] = iih.icmp_id;
STATE_LOOKUP();
if (STATE_TRANSLATE(*state)) {
if (direction == PF_IN) {
pf_change_icmp(pd2.src, &iih.icmp_id,
daddr, &(*state)->lan.addr,
(*state)->lan.port, NULL,
pd2.ip_sum, icmpsum,
pd->ip_sum, 0, AF_INET);
} else {
pf_change_icmp(pd2.dst, &iih.icmp_id,
saddr, &(*state)->gwy.addr,
(*state)->gwy.port, NULL,
pd2.ip_sum, icmpsum,
pd->ip_sum, 0, AF_INET);
}
m_copyback(m, off, ICMP_MINLEN, pd->hdr.icmp);
m_copyback(m, ipoff2, sizeof(h2), &h2);
m_copyback(m, off2, ICMP_MINLEN, &iih);
}
return (PF_PASS);
break;
}
#endif /* INET */
#ifdef INET6
case IPPROTO_ICMPV6: {
struct icmp6_hdr iih;
struct pf_tree_node key;
if (!pf_pull_hdr(m, off2, &iih,
sizeof(struct icmp6_hdr), NULL, NULL, 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[0], pd2.dst, pd2.af);
key.port[0] = iih.icmp6_id;
PF_ACPY(&key.addr[1], pd2.src, pd2.af);
key.port[1] = iih.icmp6_id;
STATE_LOOKUP();
if (STATE_TRANSLATE(*state)) {
if (direction == PF_IN) {
pf_change_icmp(pd2.src, &iih.icmp6_id,
daddr, &(*state)->lan.addr,
(*state)->lan.port, NULL,
pd2.ip_sum, icmpsum,
pd->ip_sum, 0, AF_INET6);
} else {
pf_change_icmp(pd2.dst, &iih.icmp6_id,
saddr, &(*state)->gwy.addr,
(*state)->gwy.port, NULL,
pd2.ip_sum, icmpsum,
pd->ip_sum, 0, AF_INET6);
}
m_copyback(m, off, sizeof(struct icmp6_hdr),
pd->hdr.icmp6);
m_copyback(m, ipoff2, sizeof(h2_6), &h2_6);
m_copyback(m, off2, sizeof(struct icmp6_hdr),
&iih);
}
return (PF_PASS);
break;
}
#endif /* INET6 */
default: {
struct pf_tree_node key;
key.af = pd2.af;
key.proto = pd2.proto;
PF_ACPY(&key.addr[0], pd2.dst, pd2.af);
key.port[0] = 0;
PF_ACPY(&key.addr[1], pd2.src, pd2.af);
key.port[1] = 0;
STATE_LOOKUP();
if (STATE_TRANSLATE(*state)) {
if (direction == PF_IN) {
pf_change_icmp(pd2.src, NULL,
daddr, &(*state)->lan.addr,
0, NULL,
pd2.ip_sum, icmpsum,
pd->ip_sum, 0, pd2.af);
} else {
pf_change_icmp(pd2.dst, NULL,
saddr, &(*state)->gwy.addr,
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,
pd->hdr.icmp);
m_copyback(m, ipoff2, sizeof(h2), &h2);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
m_copyback(m, off,
sizeof(struct icmp6_hdr),
pd->hdr.icmp6);
m_copyback(m, ipoff2, sizeof(h2_6),
&h2_6);
break;
#endif /* INET6 */
}
}
return (PF_PASS);
break;
}
}
}
}
int
pf_test_state_other(struct pf_state **state, int direction, struct ifnet *ifp,
struct pf_pdesc *pd)
{
struct pf_state_peer *src, *dst;
struct pf_tree_node key;
int dirndx;
key.af = pd->af;
key.proto = pd->proto;
PF_ACPY(&key.addr[0], pd->src, key.af);
PF_ACPY(&key.addr[1], pd->dst, key.af);
key.port[0] = 0;
key.port[1] = 0;
STATE_LOOKUP();
if (direction == (*state)->direction) {
src = &(*state)->src;
dst = &(*state)->dst;
dirndx = 0;
} else {
src = &(*state)->dst;
dst = &(*state)->src;
dirndx = 1;
}
(*state)->packets[dirndx]++;
(*state)->bytes[dirndx] += pd->tot_len;
/* 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.tv_sec;
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_TRANSLATE(*state)) {
if (direction == PF_OUT)
switch (pd->af) {
#ifdef INET
case AF_INET:
pf_change_a(&pd->src->v4.s_addr,
pd->ip_sum, (*state)->gwy.addr.v4.s_addr,
0);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
PF_ACPY(pd->src, &(*state)->gwy.addr, pd->af);
break;
#endif /* INET6 */
}
else
switch (pd->af) {
#ifdef INET
case AF_INET:
pf_change_a(&pd->dst->v4.s_addr,
pd->ip_sum, (*state)->lan.addr.v4.s_addr,
0);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
PF_ACPY(pd->dst, &(*state)->lan.addr, pd->af);
break;
#endif /* INET6 */
}
}
(*state)->rule.ptr->packets++;
(*state)->rule.ptr->bytes += pd->tot_len;
if ((*state)->nat_rule.ptr != NULL) {
(*state)->nat_rule.ptr->packets++;
(*state)->nat_rule.ptr->bytes += pd->tot_len;
}
if ((*state)->anchor.ptr != NULL) {
(*state)->anchor.ptr->packets++;
(*state)->anchor.ptr->bytes += pd->tot_len;
}
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 sockaddr_in *dst;
struct route ro;
int ret = 0;
bzero(&ro, sizeof(ro));
dst = satosin(&ro.ro_dst);
dst->sin_family = af;
dst->sin_len = sizeof(*dst);
dst->sin_addr = addr->v4;
rtalloc_noclone(&ro, NO_CLONING);
if (ro.ro_rt != NULL) {
ret = 1;
RTFREE(ro.ro_rt);
}
return (ret);
}
#ifdef INET
void
pf_route(struct mbuf **m, struct pf_rule *r, int dir, struct ifnet *oifp,
struct pf_state *s)
{
struct mbuf *m0, *m1;
struct route iproute;
struct route *ro;
struct sockaddr_in *dst;
struct ip *ip;
struct ifnet *ifp = NULL;
struct m_tag *mtag;
struct pf_addr naddr;
int error = 0;
if (m == NULL || *m == NULL || r == NULL ||
(dir != PF_IN && dir != PF_OUT) || oifp == NULL)
panic("pf_route: invalid parameters");
if (r->rt == PF_DUPTO) {
m0 = *m;
mtag = m_tag_find(m0, PACKET_TAG_PF_ROUTED, NULL);
if (mtag == NULL) {
mtag = m_tag_get(PACKET_TAG_PF_ROUTED, 0, M_NOWAIT);
if (mtag == NULL)
goto bad;
m_tag_prepend(m0, mtag);
}
m0 = m_copym2(*m, 0, M_COPYALL, M_NOWAIT);
if (m0 == NULL)
return;
} else {
if ((r->rt == PF_REPLYTO) == (r->direction == dir))
return;
m0 = *m;
}
if (m0->m_len < sizeof(struct ip))
panic("pf_route: m0->m_len < sizeof(struct ip)");
ip = mtod(m0, struct ip *);
ro = &iproute;
bzero((caddr_t)ro, sizeof(*ro));
dst = satosin(&ro->ro_dst);
dst->sin_family = AF_INET;
dst->sin_len = sizeof(*dst);
dst->sin_addr = ip->ip_dst;
if (r->rt == PF_FASTROUTE) {
rtalloc(ro);
if (ro->ro_rt == 0) {
ipstat.ips_noroute++;
goto bad;
}
ifp = ro->ro_rt->rt_ifp;
ro->ro_rt->rt_use++;
if (ro->ro_rt->rt_flags & RTF_GATEWAY)
dst = satosin(ro->ro_rt->rt_gateway);
} else {
if (TAILQ_EMPTY(&r->rpool.list))
panic("pf_route: TAILQ_EMPTY(&r->rpool.list)");
if (s == NULL) {
pf_map_addr(AF_INET, &r->rpool,
(struct pf_addr *)&ip->ip_src,
&naddr, NULL);
if (!PF_AZERO(&naddr, AF_INET))
dst->sin_addr.s_addr = naddr.v4.s_addr;
ifp = r->rpool.cur->ifp;
} else {
if (!PF_AZERO(&s->rt_addr, AF_INET))
dst->sin_addr.s_addr =
s->rt_addr.v4.s_addr;
ifp = s->rt_ifp;
}
}
if (ifp == NULL)
goto bad;
mtag = m_tag_find(m0, PACKET_TAG_PF_ROUTED, NULL);
if (mtag == NULL) {
struct m_tag *mtag;
mtag = m_tag_get(PACKET_TAG_PF_ROUTED, 0, M_NOWAIT);
if (mtag == NULL)
goto bad;
m_tag_prepend(m0, mtag);
}
if (oifp != ifp && mtag == NULL) {
if (pf_test(PF_OUT, ifp, &m0) != PF_PASS)
goto bad;
else if (m0 == NULL)
goto done;
if (m0->m_len < sizeof(struct ip))
panic("pf_route: m0->m_len < sizeof(struct ip)");
ip = mtod(m0, struct ip *);
}
/* Copied from ip_output. */
if (ntohs(ip->ip_len) <= ifp->if_mtu) {
if ((ifp->if_capabilities & IFCAP_CSUM_IPv4) &&
ifp->if_bridge == NULL) {
m0->m_pkthdr.csum |= M_IPV4_CSUM_OUT;
ipstat.ips_outhwcsum++;
} else {
ip->ip_sum = 0;
ip->ip_sum = in_cksum(m0, ip->ip_hl << 2);
}
/* Update relevant hardware checksum stats for TCP/UDP */
if (m0->m_pkthdr.csum & M_TCPV4_CSUM_OUT)
tcpstat.tcps_outhwcsum++;
else if (m0->m_pkthdr.csum & M_UDPV4_CSUM_OUT)
udpstat.udps_outhwcsum++;
error = (*ifp->if_output)(ifp, m0, sintosa(dst), NULL);
goto done;
}
/*
* Too large for interface; fragment if possible.
* Must be able to put at least 8 bytes per fragment.
*/
if (ip->ip_off & htons(IP_DF)) {
ipstat.ips_cantfrag++;
if (r->rt != PF_DUPTO) {
icmp_error(m0, ICMP_UNREACH, ICMP_UNREACH_NEEDFRAG, 0,
ifp);
goto done;
} else
goto bad;
}
m1 = m0;
error = ip_fragment(m0, ifp, ifp->if_mtu);
if (error == EMSGSIZE)
goto bad;
for (m0 = m1; m0; m0 = m1) {
m1 = m0->m_nextpkt;
m0->m_nextpkt = 0;
if (error == 0)
error = (*ifp->if_output)(ifp, m0, sintosa(dst),
NULL);
else
m_freem(m0);
}
if (error == 0)
ipstat.ips_fragmented++;
done:
if (r->rt != PF_DUPTO)
*m = NULL;
if (ro == &iproute && ro->ro_rt)
RTFREE(ro->ro_rt);
return;
bad:
m_freem(m0);
goto done;
}
#endif /* INET */
#ifdef INET6
void
pf_route6(struct mbuf **m, struct pf_rule *r, int dir, struct ifnet *oifp,
struct pf_state *s)
{
struct mbuf *m0;
struct m_tag *mtag;
struct route_in6 ip6route;
struct route_in6 *ro;
struct sockaddr_in6 *dst;
struct ip6_hdr *ip6;
struct ifnet *ifp = NULL;
struct pf_addr naddr;
int error = 0;
if (m == NULL || *m == NULL || r == NULL ||
(dir != PF_IN && dir != PF_OUT) || oifp == NULL)
panic("pf_route6: invalid parameters");
if (r->rt == PF_DUPTO) {
m0 = *m;
mtag = m_tag_find(m0, PACKET_TAG_PF_ROUTED, NULL);
if (mtag == NULL) {
mtag = m_tag_get(PACKET_TAG_PF_ROUTED, 0, M_NOWAIT);
if (mtag == NULL)
goto bad;
m_tag_prepend(m0, mtag);
}
m0 = m_copym2(*m, 0, M_COPYALL, M_NOWAIT);
if (m0 == NULL)
return;
} else {
if ((r->rt == PF_REPLYTO) == (r->direction == dir))
return;
m0 = *m;
}
if (m0->m_len < sizeof(struct ip6_hdr))
panic("pf_route6: m0->m_len < sizeof(struct ip6_hdr)");
ip6 = mtod(m0, struct ip6_hdr *);
ro = &ip6route;
bzero((caddr_t)ro, sizeof(*ro));
dst = (struct sockaddr_in6 *)&ro->ro_dst;
dst->sin6_family = AF_INET6;
dst->sin6_len = sizeof(*dst);
dst->sin6_addr = ip6->ip6_dst;
/* Cheat. */
if (r->rt == PF_FASTROUTE) {
mtag = m_tag_get(PACKET_TAG_PF_GENERATED, 0, M_NOWAIT);
if (mtag == NULL)
goto bad;
m_tag_prepend(m0, mtag);
ip6_output(m0, NULL, NULL, 0, NULL, NULL);
return;
}
if (TAILQ_EMPTY(&r->rpool.list))
panic("pf_route6: TAILQ_EMPTY(&r->rpool.list)");
if (s == NULL) {
pf_map_addr(AF_INET6, &r->rpool,
(struct pf_addr *)&ip6->ip6_src, &naddr, NULL);
if (!PF_AZERO(&naddr, AF_INET6))
PF_ACPY((struct pf_addr *)&dst->sin6_addr,
&naddr, AF_INET6);
ifp = r->rpool.cur->ifp;
} 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_ifp;
}
if (ifp == NULL)
goto bad;
if (oifp != ifp) {
mtag = m_tag_find(m0, PACKET_TAG_PF_ROUTED, NULL);
if (mtag == NULL) {
mtag = m_tag_get(PACKET_TAG_PF_ROUTED, 0, M_NOWAIT);
if (mtag == NULL)
goto bad;
m_tag_prepend(m0, mtag);
if (pf_test6(PF_OUT, ifp, &m0) != PF_PASS)
goto bad;
else if (m0 == NULL)
goto done;
}
}
/*
* If the packet is too large for the outgoing interface,
* send back an icmp6 error.
*/
if (IN6_IS_ADDR_LINKLOCAL(&dst->sin6_addr))
dst->sin6_addr.s6_addr16[1] = htons(ifp->if_index);
if ((u_long)m0->m_pkthdr.len <= ifp->if_mtu) {
error = 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:
m_freem(m0);
goto done;
}
#endif /* INET6 */
/*
* check protocol (tcp/udp/icmp/icmp6) checksum and set mbuf flag
* off is the offset where the protocol header starts
* len is the total length of protocol header plus payload
* returns 0 when the checksum is valid, otherwise returns 1.
*/
int
pf_check_proto_cksum(struct mbuf *m, int off, int len, u_int8_t p, sa_family_t af)
{
u_int16_t flag_ok, flag_bad;
u_int16_t sum;
switch (p) {
case IPPROTO_TCP:
flag_ok = M_TCP_CSUM_IN_OK;
flag_bad = M_TCP_CSUM_IN_BAD;
break;
case IPPROTO_UDP:
flag_ok = M_UDP_CSUM_IN_OK;
flag_bad = M_UDP_CSUM_IN_BAD;
break;
case IPPROTO_ICMP:
#ifdef INET6
case IPPROTO_ICMPV6:
#endif /* INET6 */
flag_ok = flag_bad = 0;
break;
default:
return (1);
}
if (m->m_pkthdr.csum & flag_ok)
return (0);
if (m->m_pkthdr.csum & flag_bad)
return (1);
if (off < sizeof(struct ip) || len < sizeof(struct udphdr))
return (1);
if (m->m_pkthdr.len < off + len)
return (1);
switch (af) {
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) {
m->m_pkthdr.csum |= flag_bad;
switch (p) {
case IPPROTO_TCP:
tcpstat.tcps_rcvbadsum++;
break;
case IPPROTO_UDP:
udpstat.udps_badsum++;
break;
case IPPROTO_ICMP:
icmpstat.icps_checksum++;
break;
#ifdef INET6
case IPPROTO_ICMPV6:
icmp6stat.icp6s_checksum++;
break;
#endif /* INET6 */
}
return (1);
}
m->m_pkthdr.csum |= flag_ok;
return (0);
}
#ifdef INET
int
pf_test(int dir, struct ifnet *ifp, struct mbuf **m0)
{
u_short action, reason = 0, log = 0;
struct mbuf *m = *m0;
struct ip *h;
struct pf_rule *a = NULL, *r = &pf_default_rule, *tr;
struct pf_state *s = NULL;
struct pf_ruleset *ruleset = NULL;
struct pf_pdesc pd;
int off;
int pqid = 0;
if (!pf_status.running ||
(m_tag_find(m, PACKET_TAG_PF_GENERATED, NULL) != NULL))
return (PF_PASS);
#ifdef DIAGNOSTIC
if ((m->m_flags & M_PKTHDR) == 0)
panic("non-M_PKTHDR is passed to pf_test");
#endif
if (m->m_pkthdr.len < (int)sizeof(*h)) {
action = PF_DROP;
REASON_SET(&reason, PFRES_SHORT);
log = 1;
goto done;
}
/* We do IP header normalization and packet reassembly here */
if (pf_normalize_ip(m0, dir, ifp, &reason) != PF_PASS) {
action = PF_DROP;
goto done;
}
m = *m0;
h = mtod(m, struct ip *);
off = h->ip_hl << 2;
if (off < (int)sizeof(*h)) {
action = PF_DROP;
REASON_SET(&reason, PFRES_SHORT);
log = 1;
goto done;
}
memset(&pd, 0, sizeof(pd));
pd.src = (struct pf_addr *)&h->ip_src;
pd.dst = (struct pf_addr *)&h->ip_dst;
pd.ip_sum = &h->ip_sum;
pd.proto = h->ip_p;
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, ifp, 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;
}
if (dir == PF_IN && pf_check_proto_cksum(m, off,
ntohs(h->ip_len) - off, IPPROTO_TCP, AF_INET)) {
action = PF_DROP;
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, ifp, m, 0, off, h, &pd);
if (action == PF_DROP)
break;
action = pf_test_state_tcp(&s, dir, ifp, m, 0, off, h, &pd,
&reason);
if (action == PF_PASS) {
r = s->rule.ptr;
log = s->log;
} else if (s == NULL)
action = pf_test_tcp(&r, &s, dir, ifp,
m, 0, off, h, &pd, &a, &ruleset);
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 (dir == PF_IN && uh.uh_sum && pf_check_proto_cksum(m,
off, ntohs(h->ip_len) - off, IPPROTO_UDP, AF_INET)) {
action = PF_DROP;
goto done;
}
action = pf_test_state_udp(&s, dir, ifp, m, 0, off, h, &pd);
if (action == PF_PASS) {
r = s->rule.ptr;
a = s->anchor.ptr;
log = s->log;
} else if (s == NULL)
action = pf_test_udp(&r, &s, dir, ifp,
m, 0, off, h, &pd, &a, &ruleset);
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;
}
if (dir == PF_IN && pf_check_proto_cksum(m, off,
ntohs(h->ip_len) - off, IPPROTO_ICMP, AF_INET)) {
action = PF_DROP;
goto done;
}
action = pf_test_state_icmp(&s, dir, ifp, m, 0, off, h, &pd);
if (action == PF_PASS) {
r = s->rule.ptr;
r->packets++;
r->bytes += ntohs(h->ip_len);
a = s->anchor.ptr;
if (a != NULL) {
a->packets++;
a->bytes += ntohs(h->ip_len);
}
log = s->log;
} else if (s == NULL)
action = pf_test_icmp(&r, &s, dir, ifp,
m, 0, off, h, &pd, &a, &ruleset);
break;
}
default:
action = pf_test_state_other(&s, dir, ifp, &pd);
if (action == PF_PASS) {
r = s->rule.ptr;
a = s->anchor.ptr;
log = s->log;
} else if (s == NULL)
action = pf_test_other(&r, &s, dir, ifp, m, off, h,
&pd, &a, &ruleset);
break;
}
if (ifp == status_ifp) {
pf_status.bcounters[0][dir == PF_OUT] += pd.tot_len;
pf_status.pcounters[0][dir == PF_OUT][action != PF_PASS]++;
}
done:
tr = r;
if (r == &pf_default_rule && s != NULL && s->nat_rule.ptr != NULL)
tr = s->nat_rule.ptr;
if (tr->src.addr.type == PF_ADDR_TABLE)
pfr_update_stats(tr->src.addr.p.tbl,
(s == NULL || s->direction == dir) ? pd.src : pd.dst, pd.af,
pd.tot_len, dir == PF_OUT, r->action == PF_PASS,
tr->src.not);
if (tr->dst.addr.type == PF_ADDR_TABLE)
pfr_update_stats(tr->dst.addr.p.tbl,
(s == NULL || s->direction == dir) ? pd.dst : pd.src, pd.af,
pd.tot_len, dir == PF_OUT, r->action == PF_PASS,
tr->dst.not);
if (action == PF_PASS && h->ip_hl > 5 &&
!((s && s->allow_opts) || r->allow_opts)) {
action = PF_DROP;
REASON_SET(&reason, PFRES_SHORT);
log = 1;
DPFPRINTF(PF_DEBUG_MISC,
("pf: dropping packet with ip options\n"));
}
#ifdef ALTQ
if (action == PF_PASS && r->qid) {
struct m_tag *mtag;
struct altq_tag *atag;
mtag = m_tag_get(PACKET_TAG_PF_QID, sizeof(*atag), M_NOWAIT);
if (mtag != NULL) {
atag = (struct altq_tag *)(mtag + 1);
if (pqid || pd.tos == IPTOS_LOWDELAY)
atag->qid = r->pqid;
else
atag->qid = r->qid;
/* add hints for ecn */
atag->af = AF_INET;
atag->hdr = h;
m_tag_prepend(m, mtag);
}
}
#endif
if (log)
PFLOG_PACKET(ifp, h, m, AF_INET, dir, reason, r, a, ruleset);
if (action == PF_SYNPROXY_DROP) {
m_freem(*m0);
*m0 = NULL;
action = PF_PASS;
} else if (r->rt)
/* pf_route can free the mbuf causing *m0 to become NULL */
pf_route(m0, r, dir, ifp, s);
return (action);
}
#endif /* INET */
#ifdef INET6
int
pf_test6(int dir, struct ifnet *ifp, struct mbuf **m0)
{
u_short action, reason = 0, log = 0;
struct mbuf *m = *m0;
struct ip6_hdr *h;
struct pf_rule *a = NULL, *r = &pf_default_rule, *tr;
struct pf_state *s = NULL;
struct pf_ruleset *ruleset = NULL;
struct pf_pdesc pd;
int off, terminal = 0;
if (!pf_status.running ||
(m_tag_find(m, PACKET_TAG_PF_GENERATED, NULL) != NULL))
return (PF_PASS);
#ifdef DIAGNOSTIC
if ((m->m_flags & M_PKTHDR) == 0)
panic("non-M_PKTHDR is passed to pf_test");
#endif
if (m->m_pkthdr.len < (int)sizeof(*h)) {
action = PF_DROP;
REASON_SET(&reason, PFRES_SHORT);
log = 1;
goto done;
}
/* We do IP header normalization and packet reassembly here */
if (pf_normalize_ip6(m0, dir, ifp, &reason) != PF_PASS) {
action = PF_DROP;
goto done;
}
m = *m0;
h = mtod(m, struct ip6_hdr *);
memset(&pd, 0, sizeof(pd));
pd.src = (struct pf_addr *)&h->ip6_src;
pd.dst = (struct pf_addr *)&h->ip6_dst;
pd.ip_sum = NULL;
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, ifp, m, h,
&pd, &a, &ruleset);
if (action == PF_DROP)
REASON_SET(&reason, PFRES_FRAG);
goto done;
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, off, &opt6, sizeof(opt6),
NULL, NULL, pd.af)) {
DPFPRINTF(PF_DEBUG_MISC,
("pf: IPv6 short opt\n"));
action = PF_DROP;
REASON_SET(&reason, PFRES_SHORT);
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);
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;
}
if (dir == PF_IN && pf_check_proto_cksum(m, off,
ntohs(h->ip6_plen), IPPROTO_TCP, AF_INET6)) {
action = PF_DROP;
goto done;
}
pd.p_len = pd.tot_len - off - (th.th_off << 2);
action = pf_normalize_tcp(dir, ifp, m, 0, off, h, &pd);
if (action == PF_DROP)
break;
action = pf_test_state_tcp(&s, dir, ifp, m, 0, off, h, &pd,
&reason);
if (action == PF_PASS) {
r = s->rule.ptr;
log = s->log;
} else if (s == NULL)
action = pf_test_tcp(&r, &s, dir, ifp,
m, 0, off, h, &pd, &a, &ruleset);
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 (dir == PF_IN && uh.uh_sum && pf_check_proto_cksum(m,
off, ntohs(h->ip6_plen), IPPROTO_UDP, AF_INET6)) {
action = PF_DROP;
goto done;
}
action = pf_test_state_udp(&s, dir, ifp, m, 0, off, h, &pd);
if (action == PF_PASS) {
r = s->rule.ptr;
log = s->log;
} else if (s == NULL)
action = pf_test_udp(&r, &s, dir, ifp,
m, 0, off, h, &pd, &a, &ruleset);
break;
}
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;
}
if (dir == PF_IN && pf_check_proto_cksum(m, off,
ntohs(h->ip6_plen), IPPROTO_ICMPV6, AF_INET6)) {
action = PF_DROP;
goto done;
}
action = pf_test_state_icmp(&s, dir, ifp,
m, 0, off, h, &pd);
if (action == PF_PASS) {
r = s->rule.ptr;
r->packets++;
r->bytes += h->ip6_plen;
log = s->log;
} else if (s == NULL)
action = pf_test_icmp(&r, &s, dir, ifp,
m, 0, off, h, &pd, &a, &ruleset);
break;
}
default:
action = pf_test_other(&r, &s, dir, ifp, m, off, h,
&pd, &a, &ruleset);
break;
}
if (ifp == status_ifp) {
pf_status.bcounters[1][dir == PF_OUT] += pd.tot_len;
pf_status.pcounters[1][dir == PF_OUT][action != PF_PASS]++;
}
done:
tr = r;
if (r == &pf_default_rule && s != NULL && s->nat_rule.ptr != NULL)
tr = s->nat_rule.ptr;
if (tr->src.addr.type == PF_ADDR_TABLE)
pfr_update_stats(tr->src.addr.p.tbl,
(s == NULL || s->direction == dir) ? pd.src : pd.dst, pd.af,
pd.tot_len, dir == PF_OUT, r->action == PF_PASS,
tr->src.not);
if (tr->dst.addr.type == PF_ADDR_TABLE)
pfr_update_stats(tr->dst.addr.p.tbl,
(s == NULL || s->direction == dir) ? pd.dst : pd.src, pd.af,
pd.tot_len, dir == PF_OUT, r->action == PF_PASS,
tr->dst.not);
/* XXX handle IPv6 options, if not allowed. not implemented. */
#ifdef ALTQ
if (action == PF_PASS && r->qid) {
struct m_tag *mtag;
struct altq_tag *atag;
mtag = m_tag_get(PACKET_TAG_PF_QID, sizeof(*atag), M_NOWAIT);
if (mtag != NULL) {
atag = (struct altq_tag *)(mtag + 1);
if (pd.tos == IPTOS_LOWDELAY)
atag->qid = r->pqid;
else
atag->qid = r->qid;
/* add hints for ecn */
atag->af = AF_INET6;
atag->hdr = h;
m_tag_prepend(m, mtag);
}
}
#endif
if (log)
PFLOG_PACKET(ifp, h, m, AF_INET6, dir, reason, r, a, ruleset);
if (action == PF_SYNPROXY_DROP) {
m_freem(*m0);
*m0 = NULL;
action = PF_PASS;
} else if (r->rt)
/* pf_route6 can free the mbuf causing *m0 to become NULL */
pf_route6(m0, r, dir, ifp, s);
return (action);
}
#endif /* INET6 */