diff options
author | glebius <glebius@FreeBSD.org> | 2012-09-14 11:51:49 +0000 |
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committer | glebius <glebius@FreeBSD.org> | 2012-09-14 11:51:49 +0000 |
commit | 0ccf4838d7a8b4da2c3beaac7ea1fd977aa0ed11 (patch) | |
tree | ec60da6e90cde2e87aa91ac9450c84ce3446233a /sys/netpfil/pf/pf.c | |
parent | f99fc207edf21e7c05c1147864077ce3fe1f3e2c (diff) | |
download | FreeBSD-src-0ccf4838d7a8b4da2c3beaac7ea1fd977aa0ed11.zip FreeBSD-src-0ccf4838d7a8b4da2c3beaac7ea1fd977aa0ed11.tar.gz |
o Create directory sys/netpfil, where all packet filters should
reside, and move there ipfw(4) and pf(4).
o Move most modified parts of pf out of contrib.
Actual movements:
sys/contrib/pf/net/*.c -> sys/netpfil/pf/
sys/contrib/pf/net/*.h -> sys/net/
contrib/pf/pfctl/*.c -> sbin/pfctl
contrib/pf/pfctl/*.h -> sbin/pfctl
contrib/pf/pfctl/pfctl.8 -> sbin/pfctl
contrib/pf/pfctl/*.4 -> share/man/man4
contrib/pf/pfctl/*.5 -> share/man/man5
sys/netinet/ipfw -> sys/netpfil/ipfw
The arguable movement is pf/net/*.h -> sys/net. There are
future plans to refactor pf includes, so I decided not to
break things twice.
Not modified bits of pf left in contrib: authpf, ftp-proxy,
tftp-proxy, pflogd.
The ipfw(4) movement is planned to be merged to stable/9,
to make head and stable match.
Discussed with: bz, luigi
Diffstat (limited to 'sys/netpfil/pf/pf.c')
-rw-r--r-- | sys/netpfil/pf/pf.c | 6271 |
1 files changed, 6271 insertions, 0 deletions
diff --git a/sys/netpfil/pf/pf.c b/sys/netpfil/pf/pf.c new file mode 100644 index 0000000..a61b87b --- /dev/null +++ b/sys/netpfil/pf/pf.c @@ -0,0 +1,6271 @@ +/* $OpenBSD: pf.c,v 1.634 2009/02/27 12:37:45 henning Exp $ */ + +/* + * Copyright (c) 2001 Daniel Hartmeier + * Copyright (c) 2002 - 2008 Henning Brauer + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * - Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * - Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials provided + * with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; + * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER + * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN + * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + * + * Effort sponsored in part by the Defense Advanced Research Projects + * Agency (DARPA) and Air Force Research Laboratory, Air Force + * Materiel Command, USAF, under agreement number F30602-01-2-0537. + * + */ + +#include <sys/cdefs.h> + +__FBSDID("$FreeBSD$"); + +#include "opt_inet.h" +#include "opt_inet6.h" +#include "opt_bpf.h" +#include "opt_pf.h" + +#include <sys/param.h> +#include <sys/bus.h> +#include <sys/endian.h> +#include <sys/hash.h> +#include <sys/interrupt.h> +#include <sys/kernel.h> +#include <sys/kthread.h> +#include <sys/limits.h> +#include <sys/mbuf.h> +#include <sys/md5.h> +#include <sys/random.h> +#include <sys/refcount.h> +#include <sys/socket.h> +#include <sys/sysctl.h> +#include <sys/taskqueue.h> +#include <sys/ucred.h> + +#include <net/if.h> +#include <net/if_types.h> +#include <net/route.h> +#include <net/radix_mpath.h> +#include <net/vnet.h> + +#include <net/pfvar.h> +#include <net/pf_mtag.h> +#include <net/if_pflog.h> +#include <net/if_pfsync.h> + +#include <netinet/in_pcb.h> +#include <netinet/in_var.h> +#include <netinet/ip.h> +#include <netinet/ip_fw.h> +#include <netinet/ip_icmp.h> +#include <netinet/icmp_var.h> +#include <netinet/ip_var.h> +#include <netinet/tcp.h> +#include <netinet/tcp_fsm.h> +#include <netinet/tcp_seq.h> +#include <netinet/tcp_timer.h> +#include <netinet/tcp_var.h> +#include <netinet/udp.h> +#include <netinet/udp_var.h> + +#include <netpfil/ipfw/ip_fw_private.h> /* XXX: only for DIR_IN/DIR_OUT */ + +#ifdef INET6 +#include <netinet/ip6.h> +#include <netinet/icmp6.h> +#include <netinet6/nd6.h> +#include <netinet6/ip6_var.h> +#include <netinet6/in6_pcb.h> +#endif /* INET6 */ + +#include <machine/in_cksum.h> +#include <security/mac/mac_framework.h> + +#define DPFPRINTF(n, x) if (V_pf_status.debug >= (n)) printf x + +/* + * Global variables + */ + +/* state tables */ +VNET_DEFINE(struct pf_altqqueue, pf_altqs[2]); +VNET_DEFINE(struct pf_palist, pf_pabuf); +VNET_DEFINE(struct pf_altqqueue *, pf_altqs_active); +VNET_DEFINE(struct pf_altqqueue *, pf_altqs_inactive); +VNET_DEFINE(struct pf_status, pf_status); + +VNET_DEFINE(u_int32_t, ticket_altqs_active); +VNET_DEFINE(u_int32_t, ticket_altqs_inactive); +VNET_DEFINE(int, altqs_inactive_open); +VNET_DEFINE(u_int32_t, ticket_pabuf); + +VNET_DEFINE(MD5_CTX, pf_tcp_secret_ctx); +#define V_pf_tcp_secret_ctx VNET(pf_tcp_secret_ctx) +VNET_DEFINE(u_char, pf_tcp_secret[16]); +#define V_pf_tcp_secret VNET(pf_tcp_secret) +VNET_DEFINE(int, pf_tcp_secret_init); +#define V_pf_tcp_secret_init VNET(pf_tcp_secret_init) +VNET_DEFINE(int, pf_tcp_iss_off); +#define V_pf_tcp_iss_off VNET(pf_tcp_iss_off) + +struct pf_anchor_stackframe { + struct pf_ruleset *rs; + struct pf_rule *r; + struct pf_anchor_node *parent; + struct pf_anchor *child; +}; +VNET_DEFINE(struct pf_anchor_stackframe, pf_anchor_stack[64]); +#define V_pf_anchor_stack VNET(pf_anchor_stack) + +/* + * Queue for pf_intr() sends. + */ +static MALLOC_DEFINE(M_PFTEMP, "pf_temp", "pf(4) temporary allocations"); +struct pf_send_entry { + STAILQ_ENTRY(pf_send_entry) pfse_next; + struct mbuf *pfse_m; + enum { + PFSE_IP, + PFSE_IP6, + PFSE_ICMP, + PFSE_ICMP6, + } pfse_type; + union { + struct route ro; + struct { + int type; + int code; + int mtu; + } icmpopts; + } u; +#define pfse_ro u.ro +#define pfse_icmp_type u.icmpopts.type +#define pfse_icmp_code u.icmpopts.code +#define pfse_icmp_mtu u.icmpopts.mtu +}; + +STAILQ_HEAD(pf_send_head, pf_send_entry); +static VNET_DEFINE(struct pf_send_head, pf_sendqueue); +#define V_pf_sendqueue VNET(pf_sendqueue) + +static struct mtx pf_sendqueue_mtx; +#define PF_SENDQ_LOCK() mtx_lock(&pf_sendqueue_mtx) +#define PF_SENDQ_UNLOCK() mtx_unlock(&pf_sendqueue_mtx) + +/* + * Queue for pf_flush_task() tasks. + */ +struct pf_flush_entry { + SLIST_ENTRY(pf_flush_entry) next; + struct pf_addr addr; + sa_family_t af; + uint8_t dir; + struct pf_rule *rule; /* never dereferenced */ +}; + +SLIST_HEAD(pf_flush_head, pf_flush_entry); +static VNET_DEFINE(struct pf_flush_head, pf_flushqueue); +#define V_pf_flushqueue VNET(pf_flushqueue) +static VNET_DEFINE(struct task, pf_flushtask); +#define V_pf_flushtask VNET(pf_flushtask) + +static struct mtx pf_flushqueue_mtx; +#define PF_FLUSHQ_LOCK() mtx_lock(&pf_flushqueue_mtx) +#define PF_FLUSHQ_UNLOCK() mtx_unlock(&pf_flushqueue_mtx) + +VNET_DEFINE(struct pf_rulequeue, pf_unlinked_rules); +struct mtx pf_unlnkdrules_mtx; + +static VNET_DEFINE(uma_zone_t, pf_sources_z); +#define V_pf_sources_z VNET(pf_sources_z) +static VNET_DEFINE(uma_zone_t, pf_mtag_z); +#define V_pf_mtag_z VNET(pf_mtag_z) +VNET_DEFINE(uma_zone_t, pf_state_z); +VNET_DEFINE(uma_zone_t, pf_state_key_z); + +VNET_DEFINE(uint64_t, pf_stateid[MAXCPU]); +#define PFID_CPUBITS 8 +#define PFID_CPUSHIFT (sizeof(uint64_t) * NBBY - PFID_CPUBITS) +#define PFID_CPUMASK ((uint64_t)((1 << PFID_CPUBITS) - 1) << PFID_CPUSHIFT) +#define PFID_MAXID (~PFID_CPUMASK) +CTASSERT((1 << PFID_CPUBITS) > MAXCPU); + +static void pf_src_tree_remove_state(struct pf_state *); +static void pf_init_threshold(struct pf_threshold *, u_int32_t, + u_int32_t); +static void pf_add_threshold(struct pf_threshold *); +static int pf_check_threshold(struct pf_threshold *); + +static void pf_change_ap(struct pf_addr *, u_int16_t *, + u_int16_t *, u_int16_t *, struct pf_addr *, + u_int16_t, u_int8_t, sa_family_t); +static int pf_modulate_sack(struct mbuf *, int, struct pf_pdesc *, + struct tcphdr *, struct pf_state_peer *); +static void pf_change_icmp(struct pf_addr *, u_int16_t *, + struct pf_addr *, struct pf_addr *, u_int16_t, + u_int16_t *, u_int16_t *, u_int16_t *, + u_int16_t *, u_int8_t, sa_family_t); +static void pf_send_tcp(struct mbuf *, + const struct pf_rule *, sa_family_t, + const struct pf_addr *, const struct pf_addr *, + u_int16_t, u_int16_t, u_int32_t, u_int32_t, + u_int8_t, u_int16_t, u_int16_t, u_int8_t, int, + u_int16_t, struct ifnet *); +static void pf_send_icmp(struct mbuf *, u_int8_t, u_int8_t, + sa_family_t, struct pf_rule *); +static void pf_detach_state(struct pf_state *); +static int pf_state_key_attach(struct pf_state_key *, + struct pf_state_key *, struct pf_state *); +static void pf_state_key_detach(struct pf_state *, int); +static int pf_state_key_ctor(void *, int, void *, int); +static u_int32_t pf_tcp_iss(struct pf_pdesc *); +static int pf_test_rule(struct pf_rule **, struct pf_state **, + int, struct pfi_kif *, struct mbuf *, int, + struct pf_pdesc *, struct pf_rule **, + struct pf_ruleset **, struct inpcb *); +static int pf_create_state(struct pf_rule *, struct pf_rule *, + struct pf_rule *, struct pf_pdesc *, + struct pf_src_node *, struct pf_state_key *, + struct pf_state_key *, struct mbuf *, int, + u_int16_t, u_int16_t, int *, struct pfi_kif *, + struct pf_state **, int, u_int16_t, u_int16_t, + int); +static int pf_test_fragment(struct pf_rule **, int, + struct pfi_kif *, struct mbuf *, void *, + struct pf_pdesc *, struct pf_rule **, + struct pf_ruleset **); +static int pf_tcp_track_full(struct pf_state_peer *, + struct pf_state_peer *, struct pf_state **, + struct pfi_kif *, struct mbuf *, int, + struct pf_pdesc *, u_short *, int *); +static int pf_tcp_track_sloppy(struct pf_state_peer *, + struct pf_state_peer *, struct pf_state **, + struct pf_pdesc *, u_short *); +static int pf_test_state_tcp(struct pf_state **, int, + struct pfi_kif *, struct mbuf *, int, + void *, struct pf_pdesc *, u_short *); +static int pf_test_state_udp(struct pf_state **, int, + struct pfi_kif *, struct mbuf *, int, + void *, struct pf_pdesc *); +static int pf_test_state_icmp(struct pf_state **, int, + struct pfi_kif *, struct mbuf *, int, + void *, struct pf_pdesc *, u_short *); +static int pf_test_state_other(struct pf_state **, int, + struct pfi_kif *, struct mbuf *, struct pf_pdesc *); +static u_int8_t pf_get_wscale(struct mbuf *, int, u_int16_t, + sa_family_t); +static u_int16_t pf_get_mss(struct mbuf *, int, u_int16_t, + sa_family_t); +static u_int16_t pf_calc_mss(struct pf_addr *, sa_family_t, + int, u_int16_t); +static void pf_set_rt_ifp(struct pf_state *, + struct pf_addr *); +static int pf_check_proto_cksum(struct mbuf *, int, int, + u_int8_t, sa_family_t); +static void pf_print_state_parts(struct pf_state *, + struct pf_state_key *, struct pf_state_key *); +static int pf_addr_wrap_neq(struct pf_addr_wrap *, + struct pf_addr_wrap *); +static struct pf_state *pf_find_state(struct pfi_kif *, + struct pf_state_key_cmp *, u_int); +static int pf_src_connlimit(struct pf_state **); +static void pf_flush_task(void *c, int pending); +static int pf_insert_src_node(struct pf_src_node **, + struct pf_rule *, struct pf_addr *, sa_family_t); +static int pf_purge_expired_states(int); +static void pf_purge_unlinked_rules(void); +static int pf_mtag_init(void *, int, int); +static void pf_mtag_free(struct m_tag *); +#ifdef INET +static void pf_route(struct mbuf **, struct pf_rule *, int, + struct ifnet *, struct pf_state *, + struct pf_pdesc *); +#endif /* INET */ +#ifdef INET6 +static void pf_change_a6(struct pf_addr *, u_int16_t *, + struct pf_addr *, u_int8_t); +static void pf_route6(struct mbuf **, struct pf_rule *, int, + struct ifnet *, struct pf_state *, + struct pf_pdesc *); +#endif /* INET6 */ + +int in4_cksum(struct mbuf *m, u_int8_t nxt, int off, int len); + +VNET_DECLARE(int, pf_end_threads); + +VNET_DEFINE(struct pf_limit, pf_limits[PF_LIMIT_MAX]); + +#define PACKET_LOOPED(pd) ((pd)->pf_mtag && \ + (pd)->pf_mtag->flags & PF_PACKET_LOOPED) + +#define STATE_LOOKUP(i, k, d, s, pd) \ + do { \ + (s) = pf_find_state((i), (k), (d)); \ + if ((s) == NULL || (s)->timeout == PFTM_PURGE) \ + return (PF_DROP); \ + if (PACKET_LOOPED(pd)) \ + return (PF_PASS); \ + if ((d) == PF_OUT && \ + (((s)->rule.ptr->rt == PF_ROUTETO && \ + (s)->rule.ptr->direction == PF_OUT) || \ + ((s)->rule.ptr->rt == PF_REPLYTO && \ + (s)->rule.ptr->direction == PF_IN)) && \ + (s)->rt_kif != NULL && \ + (s)->rt_kif != (i)) \ + return (PF_PASS); \ + } while (0) + +#define BOUND_IFACE(r, k) \ + ((r)->rule_flag & PFRULE_IFBOUND) ? (k) : V_pfi_all + +#define STATE_INC_COUNTERS(s) \ + do { \ + s->rule.ptr->states_cur++; \ + s->rule.ptr->states_tot++; \ + if (s->anchor.ptr != NULL) { \ + s->anchor.ptr->states_cur++; \ + s->anchor.ptr->states_tot++; \ + } \ + if (s->nat_rule.ptr != NULL) { \ + s->nat_rule.ptr->states_cur++; \ + s->nat_rule.ptr->states_tot++; \ + } \ + } while (0) + +#define STATE_DEC_COUNTERS(s) \ + do { \ + if (s->nat_rule.ptr != NULL) \ + s->nat_rule.ptr->states_cur--; \ + if (s->anchor.ptr != NULL) \ + s->anchor.ptr->states_cur--; \ + s->rule.ptr->states_cur--; \ + } while (0) + +static MALLOC_DEFINE(M_PFHASH, "pf_hash", "pf(4) hash header structures"); +VNET_DEFINE(struct pf_keyhash *, pf_keyhash); +VNET_DEFINE(struct pf_idhash *, pf_idhash); +VNET_DEFINE(u_long, pf_hashmask); +VNET_DEFINE(struct pf_srchash *, pf_srchash); +VNET_DEFINE(u_long, pf_srchashmask); + +SYSCTL_NODE(_net, OID_AUTO, pf, CTLFLAG_RW, 0, "pf(4)"); + +VNET_DEFINE(u_long, pf_hashsize); +#define V_pf_hashsize VNET(pf_hashsize) +SYSCTL_VNET_UINT(_net_pf, OID_AUTO, states_hashsize, CTLFLAG_RDTUN, + &VNET_NAME(pf_hashsize), 0, "Size of pf(4) states hashtable"); + +VNET_DEFINE(u_long, pf_srchashsize); +#define V_pf_srchashsize VNET(pf_srchashsize) +SYSCTL_VNET_UINT(_net_pf, OID_AUTO, source_nodes_hashsize, CTLFLAG_RDTUN, + &VNET_NAME(pf_srchashsize), 0, "Size of pf(4) source nodes hashtable"); + +VNET_DEFINE(void *, pf_swi_cookie); + +VNET_DEFINE(uint32_t, pf_hashseed); +#define V_pf_hashseed VNET(pf_hashseed) + +static __inline uint32_t +pf_hashkey(struct pf_state_key *sk) +{ + uint32_t h; + + h = jenkins_hash32((uint32_t *)sk, + sizeof(struct pf_state_key_cmp)/sizeof(uint32_t), + V_pf_hashseed); + + return (h & V_pf_hashmask); +} + +#ifdef INET6 +void +pf_addrcpy(struct pf_addr *dst, struct pf_addr *src, sa_family_t af) +{ + switch (af) { +#ifdef INET + case AF_INET: + dst->addr32[0] = src->addr32[0]; + break; +#endif /* INET */ + case AF_INET6: + dst->addr32[0] = src->addr32[0]; + dst->addr32[1] = src->addr32[1]; + dst->addr32[2] = src->addr32[2]; + dst->addr32[3] = src->addr32[3]; + break; + } +} +#endif /* INET6 */ + +static void +pf_init_threshold(struct pf_threshold *threshold, + u_int32_t limit, u_int32_t seconds) +{ + threshold->limit = limit * PF_THRESHOLD_MULT; + threshold->seconds = seconds; + threshold->count = 0; + threshold->last = time_uptime; +} + +static void +pf_add_threshold(struct pf_threshold *threshold) +{ + u_int32_t t = time_uptime, diff = t - threshold->last; + + if (diff >= threshold->seconds) + threshold->count = 0; + else + threshold->count -= threshold->count * diff / + threshold->seconds; + threshold->count += PF_THRESHOLD_MULT; + threshold->last = t; +} + +static int +pf_check_threshold(struct pf_threshold *threshold) +{ + return (threshold->count > threshold->limit); +} + +static int +pf_src_connlimit(struct pf_state **state) +{ + struct pfr_addr p; + struct pf_flush_entry *pffe; + int bad = 0; + + PF_STATE_LOCK_ASSERT(*state); + + (*state)->src_node->conn++; + (*state)->src.tcp_est = 1; + pf_add_threshold(&(*state)->src_node->conn_rate); + + if ((*state)->rule.ptr->max_src_conn && + (*state)->rule.ptr->max_src_conn < + (*state)->src_node->conn) { + V_pf_status.lcounters[LCNT_SRCCONN]++; + bad++; + } + + if ((*state)->rule.ptr->max_src_conn_rate.limit && + pf_check_threshold(&(*state)->src_node->conn_rate)) { + V_pf_status.lcounters[LCNT_SRCCONNRATE]++; + bad++; + } + + if (!bad) + return (0); + + /* Kill this state. */ + (*state)->timeout = PFTM_PURGE; + (*state)->src.state = (*state)->dst.state = TCPS_CLOSED; + + if ((*state)->rule.ptr->overload_tbl == NULL) + return (1); + + V_pf_status.lcounters[LCNT_OVERLOAD_TABLE]++; + if (V_pf_status.debug >= PF_DEBUG_MISC) { + printf("%s: blocking address ", __func__); + pf_print_host(&(*state)->src_node->addr, 0, + (*state)->key[PF_SK_WIRE]->af); + printf("\n"); + } + + bzero(&p, sizeof(p)); + p.pfra_af = (*state)->key[PF_SK_WIRE]->af; + switch ((*state)->key[PF_SK_WIRE]->af) { +#ifdef INET + case AF_INET: + p.pfra_net = 32; + p.pfra_ip4addr = (*state)->src_node->addr.v4; + break; +#endif /* INET */ +#ifdef INET6 + case AF_INET6: + p.pfra_net = 128; + p.pfra_ip6addr = (*state)->src_node->addr.v6; + break; +#endif /* INET6 */ + } + + pfr_insert_kentry((*state)->rule.ptr->overload_tbl, &p, time_second); + + if ((*state)->rule.ptr->flush == 0) + return (1); + + /* Schedule flushing task. */ + pffe = malloc(sizeof(*pffe), M_PFTEMP, M_NOWAIT); + if (pffe == NULL) + return (1); /* too bad :( */ + + bcopy(&(*state)->src_node->addr, &pffe->addr, sizeof(pffe->addr)); + pffe->af = (*state)->key[PF_SK_WIRE]->af; + pffe->dir = (*state)->direction; + if ((*state)->rule.ptr->flush & PF_FLUSH_GLOBAL) + pffe->rule = NULL; + else + pffe->rule = (*state)->rule.ptr; + PF_FLUSHQ_LOCK(); + SLIST_INSERT_HEAD(&V_pf_flushqueue, pffe, next); + PF_FLUSHQ_UNLOCK(); + taskqueue_enqueue(taskqueue_swi, &V_pf_flushtask); + + return (1); +} + +static void +pf_flush_task(void *c, int pending) +{ + struct pf_flush_head queue; + struct pf_flush_entry *pffe, *pffe1; + uint32_t killed = 0; + + PF_FLUSHQ_LOCK(); + queue = *(struct pf_flush_head *)c; + SLIST_INIT((struct pf_flush_head *)c); + PF_FLUSHQ_UNLOCK(); + + V_pf_status.lcounters[LCNT_OVERLOAD_FLUSH]++; + + for (int i = 0; i <= V_pf_hashmask; i++) { + struct pf_idhash *ih = &V_pf_idhash[i]; + struct pf_state_key *sk; + struct pf_state *s; + + PF_HASHROW_LOCK(ih); + LIST_FOREACH(s, &ih->states, entry) { + sk = s->key[PF_SK_WIRE]; + SLIST_FOREACH(pffe, &queue, next) + if (sk->af == pffe->af && (pffe->rule == NULL || + pffe->rule == s->rule.ptr) && + ((pffe->dir == PF_OUT && + PF_AEQ(&pffe->addr, &sk->addr[1], sk->af)) || + (pffe->dir == PF_IN && + PF_AEQ(&pffe->addr, &sk->addr[0], sk->af)))) { + s->timeout = PFTM_PURGE; + s->src.state = s->dst.state = TCPS_CLOSED; + killed++; + } + } + PF_HASHROW_UNLOCK(ih); + } + SLIST_FOREACH_SAFE(pffe, &queue, next, pffe1) + free(pffe, M_PFTEMP); + if (V_pf_status.debug >= PF_DEBUG_MISC) + printf("%s: %u states killed", __func__, killed); +} + +/* + * Can return locked on failure, so that we can consistently + * allocate and insert a new one. + */ +struct pf_src_node * +pf_find_src_node(struct pf_addr *src, struct pf_rule *rule, sa_family_t af, + int returnlocked) +{ + struct pf_srchash *sh; + struct pf_src_node *n; + + V_pf_status.scounters[SCNT_SRC_NODE_SEARCH]++; + + sh = &V_pf_srchash[pf_hashsrc(src, af)]; + PF_HASHROW_LOCK(sh); + LIST_FOREACH(n, &sh->nodes, entry) + if (n->rule.ptr == rule && n->af == af && + ((af == AF_INET && n->addr.v4.s_addr == src->v4.s_addr) || + (af == AF_INET6 && bcmp(&n->addr, src, sizeof(*src)) == 0))) + break; + if (n != NULL || returnlocked == 0) + PF_HASHROW_UNLOCK(sh); + + return (n); +} + +static int +pf_insert_src_node(struct pf_src_node **sn, struct pf_rule *rule, + struct pf_addr *src, sa_family_t af) +{ + + KASSERT((rule->rule_flag & PFRULE_RULESRCTRACK || + rule->rpool.opts & PF_POOL_STICKYADDR), + ("%s for non-tracking rule %p", __func__, rule)); + + if (*sn == NULL) + *sn = pf_find_src_node(src, rule, af, 1); + + if (*sn == NULL) { + struct pf_srchash *sh = &V_pf_srchash[pf_hashsrc(src, af)]; + + PF_HASHROW_ASSERT(sh); + + if (!rule->max_src_nodes || + rule->src_nodes < rule->max_src_nodes) + (*sn) = uma_zalloc(V_pf_sources_z, M_NOWAIT | M_ZERO); + else + V_pf_status.lcounters[LCNT_SRCNODES]++; + if ((*sn) == NULL) { + PF_HASHROW_UNLOCK(sh); + return (-1); + } + + pf_init_threshold(&(*sn)->conn_rate, + rule->max_src_conn_rate.limit, + rule->max_src_conn_rate.seconds); + + (*sn)->af = af; + (*sn)->rule.ptr = rule; + PF_ACPY(&(*sn)->addr, src, af); + LIST_INSERT_HEAD(&sh->nodes, *sn, entry); + (*sn)->creation = time_uptime; + (*sn)->ruletype = rule->action; + if ((*sn)->rule.ptr != NULL) + (*sn)->rule.ptr->src_nodes++; + PF_HASHROW_UNLOCK(sh); + V_pf_status.scounters[SCNT_SRC_NODE_INSERT]++; + V_pf_status.src_nodes++; + } else { + if (rule->max_src_states && + (*sn)->states >= rule->max_src_states) { + V_pf_status.lcounters[LCNT_SRCSTATES]++; + return (-1); + } + } + return (0); +} + +static void +pf_remove_src_node(struct pf_src_node *src) +{ + struct pf_srchash *sh; + + sh = &V_pf_srchash[pf_hashsrc(&src->addr, src->af)]; + PF_HASHROW_LOCK(sh); + LIST_REMOVE(src, entry); + PF_HASHROW_UNLOCK(sh); +} + +/* Data storage structures initialization. */ +void +pf_initialize() +{ + struct pf_keyhash *kh; + struct pf_idhash *ih; + struct pf_srchash *sh; + u_int i; + + TUNABLE_ULONG_FETCH("net.pf.states_hashsize", &V_pf_hashsize); + if (V_pf_hashsize == 0 || !powerof2(V_pf_hashsize)) + V_pf_hashsize = PF_HASHSIZ; + TUNABLE_ULONG_FETCH("net.pf.source_nodes_hashsize", &V_pf_srchashsize); + if (V_pf_srchashsize == 0 || !powerof2(V_pf_srchashsize)) + V_pf_srchashsize = PF_HASHSIZ / 4; + + V_pf_hashseed = arc4random(); + + /* States and state keys storage. */ + V_pf_state_z = uma_zcreate("pf states", sizeof(struct pf_state), + NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); + V_pf_limits[PF_LIMIT_STATES].zone = V_pf_state_z; + uma_zone_set_max(V_pf_state_z, PFSTATE_HIWAT); + + V_pf_state_key_z = uma_zcreate("pf state keys", + sizeof(struct pf_state_key), pf_state_key_ctor, NULL, NULL, NULL, + UMA_ALIGN_PTR, 0); + V_pf_keyhash = malloc(V_pf_hashsize * sizeof(struct pf_keyhash), + M_PFHASH, M_WAITOK | M_ZERO); + V_pf_idhash = malloc(V_pf_hashsize * sizeof(struct pf_idhash), + M_PFHASH, M_WAITOK | M_ZERO); + V_pf_hashmask = V_pf_hashsize - 1; + for (i = 0, kh = V_pf_keyhash, ih = V_pf_idhash; i <= V_pf_hashmask; + i++, kh++, ih++) { + mtx_init(&kh->lock, "pf_keyhash", NULL, MTX_DEF); + mtx_init(&ih->lock, "pf_idhash", NULL, MTX_DEF); + } + + /* Source nodes. */ + V_pf_sources_z = uma_zcreate("pf source nodes", + sizeof(struct pf_src_node), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, + 0); + V_pf_limits[PF_LIMIT_SRC_NODES].zone = V_pf_sources_z; + uma_zone_set_max(V_pf_sources_z, PFSNODE_HIWAT); + V_pf_srchash = malloc(V_pf_srchashsize * sizeof(struct pf_srchash), + M_PFHASH, M_WAITOK|M_ZERO); + V_pf_srchashmask = V_pf_srchashsize - 1; + for (i = 0, sh = V_pf_srchash; i <= V_pf_srchashmask; i++, sh++) + mtx_init(&sh->lock, "pf_srchash", NULL, MTX_DEF); + + /* ALTQ */ + TAILQ_INIT(&V_pf_altqs[0]); + TAILQ_INIT(&V_pf_altqs[1]); + TAILQ_INIT(&V_pf_pabuf); + V_pf_altqs_active = &V_pf_altqs[0]; + V_pf_altqs_inactive = &V_pf_altqs[1]; + + /* Mbuf tags */ + V_pf_mtag_z = uma_zcreate("pf mtags", sizeof(struct m_tag) + + sizeof(struct pf_mtag), NULL, NULL, pf_mtag_init, NULL, + UMA_ALIGN_PTR, 0); + + /* Send & flush queues. */ + STAILQ_INIT(&V_pf_sendqueue); + SLIST_INIT(&V_pf_flushqueue); + TASK_INIT(&V_pf_flushtask, 0, pf_flush_task, &V_pf_flushqueue); + mtx_init(&pf_sendqueue_mtx, "pf send queue", NULL, MTX_DEF); + mtx_init(&pf_flushqueue_mtx, "pf flush queue", NULL, MTX_DEF); + + /* Unlinked, but may be referenced rules. */ + TAILQ_INIT(&V_pf_unlinked_rules); + mtx_init(&pf_unlnkdrules_mtx, "pf unlinked rules", NULL, MTX_DEF); +} + +void +pf_cleanup() +{ + struct pf_keyhash *kh; + struct pf_idhash *ih; + struct pf_srchash *sh; + struct pf_send_entry *pfse, *next; + u_int i; + + for (i = 0, kh = V_pf_keyhash, ih = V_pf_idhash; i <= V_pf_hashmask; + i++, kh++, ih++) { + KASSERT(LIST_EMPTY(&kh->keys), ("%s: key hash not empty", + __func__)); + KASSERT(LIST_EMPTY(&ih->states), ("%s: id hash not empty", + __func__)); + mtx_destroy(&kh->lock); + mtx_destroy(&ih->lock); + } + free(V_pf_keyhash, M_PFHASH); + free(V_pf_idhash, M_PFHASH); + + for (i = 0, sh = V_pf_srchash; i <= V_pf_srchashmask; i++, sh++) { + KASSERT(LIST_EMPTY(&sh->nodes), + ("%s: source node hash not empty", __func__)); + mtx_destroy(&sh->lock); + } + free(V_pf_srchash, M_PFHASH); + + STAILQ_FOREACH_SAFE(pfse, &V_pf_sendqueue, pfse_next, next) { + m_freem(pfse->pfse_m); + free(pfse, M_PFTEMP); + } + + mtx_destroy(&pf_sendqueue_mtx); + mtx_destroy(&pf_flushqueue_mtx); + mtx_destroy(&pf_unlnkdrules_mtx); + + uma_zdestroy(V_pf_mtag_z); + uma_zdestroy(V_pf_sources_z); + uma_zdestroy(V_pf_state_z); + uma_zdestroy(V_pf_state_key_z); +} + +static int +pf_mtag_init(void *mem, int size, int how) +{ + struct m_tag *t; + + t = (struct m_tag *)mem; + t->m_tag_cookie = MTAG_ABI_COMPAT; + t->m_tag_id = PACKET_TAG_PF; + t->m_tag_len = sizeof(struct pf_mtag); + t->m_tag_free = pf_mtag_free; + + return (0); +} + +static void +pf_mtag_free(struct m_tag *t) +{ + + uma_zfree(V_pf_mtag_z, t); +} + +struct pf_mtag * +pf_get_mtag(struct mbuf *m) +{ + struct m_tag *mtag; + + if ((mtag = m_tag_find(m, PACKET_TAG_PF, NULL)) != NULL) + return ((struct pf_mtag *)(mtag + 1)); + + mtag = uma_zalloc(V_pf_mtag_z, M_NOWAIT); + if (mtag == NULL) + return (NULL); + bzero(mtag + 1, sizeof(struct pf_mtag)); + m_tag_prepend(m, mtag); + + return ((struct pf_mtag *)(mtag + 1)); +} + +static int +pf_state_key_attach(struct pf_state_key *skw, struct pf_state_key *sks, + struct pf_state *s) +{ + struct pf_keyhash *kh; + struct pf_state_key *sk, *cur; + struct pf_state *si, *olds = NULL; + int idx; + + KASSERT(s->refs == 0, ("%s: state not pristine", __func__)); + KASSERT(s->key[PF_SK_WIRE] == NULL, ("%s: state has key", __func__)); + KASSERT(s->key[PF_SK_STACK] == NULL, ("%s: state has key", __func__)); + + /* + * First run: start with wire key. + */ + sk = skw; + idx = PF_SK_WIRE; + +keyattach: + kh = &V_pf_keyhash[pf_hashkey(sk)]; + + PF_HASHROW_LOCK(kh); + LIST_FOREACH(cur, &kh->keys, entry) + if (bcmp(cur, sk, sizeof(struct pf_state_key_cmp)) == 0) + break; + + if (cur != NULL) { + /* Key exists. Check for same kif, if none, add to key. */ + TAILQ_FOREACH(si, &cur->states[idx], key_list[idx]) { + struct pf_idhash *ih = &V_pf_idhash[PF_IDHASH(si)]; + + PF_HASHROW_LOCK(ih); + if (si->kif == s->kif && + si->direction == s->direction) { + if (sk->proto == IPPROTO_TCP && + si->src.state >= TCPS_FIN_WAIT_2 && + si->dst.state >= TCPS_FIN_WAIT_2) { + si->src.state = si->dst.state = + TCPS_CLOSED; + /* Unlink later or cur can go away. */ + pf_ref_state(si); + olds = si; + } else { + if (V_pf_status.debug >= PF_DEBUG_MISC) { + printf("pf: %s key attach " + "failed on %s: ", + (idx == PF_SK_WIRE) ? + "wire" : "stack", + s->kif->pfik_name); + pf_print_state_parts(s, + (idx == PF_SK_WIRE) ? + sk : NULL, + (idx == PF_SK_STACK) ? + sk : NULL); + printf(", existing: "); + pf_print_state_parts(si, + (idx == PF_SK_WIRE) ? + sk : NULL, + (idx == PF_SK_STACK) ? + sk : NULL); + printf("\n"); + } + PF_HASHROW_UNLOCK(ih); + PF_HASHROW_UNLOCK(kh); + uma_zfree(V_pf_state_key_z, sk); + if (idx == PF_SK_STACK) + pf_detach_state(s); + return (-1); /* collision! */ + } + } + PF_HASHROW_UNLOCK(ih); + } + uma_zfree(V_pf_state_key_z, sk); + s->key[idx] = cur; + } else { + LIST_INSERT_HEAD(&kh->keys, sk, entry); + s->key[idx] = sk; + } + +stateattach: + /* List is sorted, if-bound states before floating. */ + if (s->kif == V_pfi_all) + TAILQ_INSERT_TAIL(&s->key[idx]->states[idx], s, key_list[idx]); + else + TAILQ_INSERT_HEAD(&s->key[idx]->states[idx], s, key_list[idx]); + + /* + * Attach done. See how should we (or should not?) + * attach a second key. + */ + if (sks == skw) { + s->key[PF_SK_STACK] = s->key[PF_SK_WIRE]; + idx = PF_SK_STACK; + sks = NULL; + goto stateattach; + } else if (sks != NULL) { + PF_HASHROW_UNLOCK(kh); + if (olds) { + pf_unlink_state(olds, 0); + pf_release_state(olds); + olds = NULL; + } + /* + * Continue attaching with stack key. + */ + sk = sks; + idx = PF_SK_STACK; + sks = NULL; + goto keyattach; + } else + PF_HASHROW_UNLOCK(kh); + + if (olds) { + pf_unlink_state(olds, 0); + pf_release_state(olds); + } + + KASSERT(s->key[PF_SK_WIRE] != NULL && s->key[PF_SK_STACK] != NULL, + ("%s failure", __func__)); + + return (0); +} + +static void +pf_detach_state(struct pf_state *s) +{ + struct pf_state_key *sks = s->key[PF_SK_STACK]; + struct pf_keyhash *kh; + + if (sks != NULL) { + kh = &V_pf_keyhash[pf_hashkey(sks)]; + PF_HASHROW_LOCK(kh); + if (s->key[PF_SK_STACK] != NULL) + pf_state_key_detach(s, PF_SK_STACK); + /* + * If both point to same key, then we are done. + */ + if (sks == s->key[PF_SK_WIRE]) { + pf_state_key_detach(s, PF_SK_WIRE); + PF_HASHROW_UNLOCK(kh); + return; + } + PF_HASHROW_UNLOCK(kh); + } + + if (s->key[PF_SK_WIRE] != NULL) { + kh = &V_pf_keyhash[pf_hashkey(s->key[PF_SK_WIRE])]; + PF_HASHROW_LOCK(kh); + if (s->key[PF_SK_WIRE] != NULL) + pf_state_key_detach(s, PF_SK_WIRE); + PF_HASHROW_UNLOCK(kh); + } +} + +static void +pf_state_key_detach(struct pf_state *s, int idx) +{ + struct pf_state_key *sk = s->key[idx]; +#ifdef INVARIANTS + struct pf_keyhash *kh = &V_pf_keyhash[pf_hashkey(sk)]; + + PF_HASHROW_ASSERT(kh); +#endif + TAILQ_REMOVE(&sk->states[idx], s, key_list[idx]); + s->key[idx] = NULL; + + if (TAILQ_EMPTY(&sk->states[0]) && TAILQ_EMPTY(&sk->states[1])) { + LIST_REMOVE(sk, entry); + uma_zfree(V_pf_state_key_z, sk); + } +} + +static int +pf_state_key_ctor(void *mem, int size, void *arg, int flags) +{ + struct pf_state_key *sk = mem; + + bzero(sk, sizeof(struct pf_state_key_cmp)); + TAILQ_INIT(&sk->states[PF_SK_WIRE]); + TAILQ_INIT(&sk->states[PF_SK_STACK]); + + return (0); +} + +struct pf_state_key * +pf_state_key_setup(struct pf_pdesc *pd, struct pf_addr *saddr, + struct pf_addr *daddr, u_int16_t sport, u_int16_t dport) +{ + struct pf_state_key *sk; + + sk = uma_zalloc(V_pf_state_key_z, M_NOWAIT); + if (sk == NULL) + return (NULL); + + PF_ACPY(&sk->addr[pd->sidx], saddr, pd->af); + PF_ACPY(&sk->addr[pd->didx], daddr, pd->af); + sk->port[pd->sidx] = sport; + sk->port[pd->didx] = dport; + sk->proto = pd->proto; + sk->af = pd->af; + + return (sk); +} + +struct pf_state_key * +pf_state_key_clone(struct pf_state_key *orig) +{ + struct pf_state_key *sk; + + sk = uma_zalloc(V_pf_state_key_z, M_NOWAIT); + if (sk == NULL) + return (NULL); + + bcopy(orig, sk, sizeof(struct pf_state_key_cmp)); + + return (sk); +} + +int +pf_state_insert(struct pfi_kif *kif, struct pf_state_key *skw, + struct pf_state_key *sks, struct pf_state *s) +{ + struct pf_idhash *ih; + struct pf_state *cur; + + KASSERT(TAILQ_EMPTY(&sks->states[0]) && TAILQ_EMPTY(&sks->states[1]), + ("%s: sks not pristine", __func__)); + KASSERT(TAILQ_EMPTY(&skw->states[0]) && TAILQ_EMPTY(&skw->states[1]), + ("%s: skw not pristine", __func__)); + KASSERT(s->refs == 0, ("%s: state not pristine", __func__)); + + s->kif = kif; + + if (pf_state_key_attach(skw, sks, s)) + return (-1); + + if (s->id == 0 && s->creatorid == 0) { + /* XXX: should be atomic, but probability of collision low */ + if ((s->id = V_pf_stateid[curcpu]++) == PFID_MAXID) + V_pf_stateid[curcpu] = 1; + s->id |= (uint64_t )curcpu << PFID_CPUSHIFT; + s->id = htobe64(s->id); + s->creatorid = V_pf_status.hostid; + } + + ih = &V_pf_idhash[PF_IDHASH(s)]; + PF_HASHROW_LOCK(ih); + LIST_FOREACH(cur, &ih->states, entry) + if (cur->id == s->id && cur->creatorid == s->creatorid) + break; + + if (cur != NULL) { + PF_HASHROW_UNLOCK(ih); + if (V_pf_status.debug >= PF_DEBUG_MISC) { + printf("pf: state insert failed: " + "id: %016llx creatorid: %08x", + (unsigned long long)be64toh(s->id), + ntohl(s->creatorid)); + printf("\n"); + } + pf_detach_state(s); + return (-1); + } + LIST_INSERT_HEAD(&ih->states, s, entry); + /* One for keys, one for ID hash. */ + refcount_init(&s->refs, 2); + + V_pf_status.fcounters[FCNT_STATE_INSERT]++; + if (pfsync_insert_state_ptr != NULL) + pfsync_insert_state_ptr(s); + + /* Returns locked. */ + return (0); +} + +/* + * Find state by ID: returns with locked row on success. + */ +struct pf_state * +pf_find_state_byid(uint64_t id, uint32_t creatorid) +{ + struct pf_idhash *ih; + struct pf_state *s; + + V_pf_status.fcounters[FCNT_STATE_SEARCH]++; + + ih = &V_pf_idhash[(be64toh(id) % (V_pf_hashmask + 1))]; + + PF_HASHROW_LOCK(ih); + LIST_FOREACH(s, &ih->states, entry) + if (s->id == id && s->creatorid == creatorid) + break; + + if (s == NULL) + PF_HASHROW_UNLOCK(ih); + + return (s); +} + +/* + * Find state by key. + * Returns with ID hash slot locked on success. + */ +static struct pf_state * +pf_find_state(struct pfi_kif *kif, struct pf_state_key_cmp *key, u_int dir) +{ + struct pf_keyhash *kh; + struct pf_state_key *sk; + struct pf_state *s; + int idx; + + V_pf_status.fcounters[FCNT_STATE_SEARCH]++; + + kh = &V_pf_keyhash[pf_hashkey((struct pf_state_key *)key)]; + + PF_HASHROW_LOCK(kh); + LIST_FOREACH(sk, &kh->keys, entry) + if (bcmp(sk, key, sizeof(struct pf_state_key_cmp)) == 0) + break; + if (sk == NULL) { + PF_HASHROW_UNLOCK(kh); + return (NULL); + } + + idx = (dir == PF_IN ? PF_SK_WIRE : PF_SK_STACK); + + /* List is sorted, if-bound states before floating ones. */ + TAILQ_FOREACH(s, &sk->states[idx], key_list[idx]) + if (s->kif == V_pfi_all || s->kif == kif) { + PF_STATE_LOCK(s); + PF_HASHROW_UNLOCK(kh); + if (s->timeout == PFTM_UNLINKED) { + /* + * State is being processed + * by pf_unlink_state() in + * an other thread. + */ + PF_STATE_UNLOCK(s); + return (NULL); + } + return (s); + } + PF_HASHROW_UNLOCK(kh); + + return (NULL); +} + +struct pf_state * +pf_find_state_all(struct pf_state_key_cmp *key, u_int dir, int *more) +{ + struct pf_keyhash *kh; + struct pf_state_key *sk; + struct pf_state *s, *ret = NULL; + int idx, inout = 0; + + V_pf_status.fcounters[FCNT_STATE_SEARCH]++; + + kh = &V_pf_keyhash[pf_hashkey((struct pf_state_key *)key)]; + + PF_HASHROW_LOCK(kh); + LIST_FOREACH(sk, &kh->keys, entry) + if (bcmp(sk, key, sizeof(struct pf_state_key_cmp)) == 0) + break; + if (sk == NULL) { + PF_HASHROW_UNLOCK(kh); + return (NULL); + } + switch (dir) { + case PF_IN: + idx = PF_SK_WIRE; + break; + case PF_OUT: + idx = PF_SK_STACK; + break; + case PF_INOUT: + idx = PF_SK_WIRE; + inout = 1; + break; + default: + panic("%s: dir %u", __func__, dir); + } +second_run: + TAILQ_FOREACH(s, &sk->states[idx], key_list[idx]) { + if (more == NULL) { + PF_HASHROW_UNLOCK(kh); + return (s); + } + + if (ret) + (*more)++; + else + ret = s; + } + if (inout == 1) { + inout = 0; + idx = PF_SK_STACK; + goto second_run; + } + PF_HASHROW_UNLOCK(kh); + + return (ret); +} + +/* END state table stuff */ + +static void +pf_send(struct pf_send_entry *pfse) +{ + + PF_SENDQ_LOCK(); + STAILQ_INSERT_TAIL(&V_pf_sendqueue, pfse, pfse_next); + PF_SENDQ_UNLOCK(); + swi_sched(V_pf_swi_cookie, 0); +} + +void +pf_intr(void *v) +{ + struct pf_send_head queue; + struct pf_send_entry *pfse, *next; + + CURVNET_SET((struct vnet *)v); + + PF_SENDQ_LOCK(); + queue = V_pf_sendqueue; + STAILQ_INIT(&V_pf_sendqueue); + PF_SENDQ_UNLOCK(); + + STAILQ_FOREACH_SAFE(pfse, &queue, pfse_next, next) { + switch (pfse->pfse_type) { +#ifdef INET + case PFSE_IP: + ip_output(pfse->pfse_m, NULL, NULL, 0, NULL, NULL); + break; + case PFSE_ICMP: + icmp_error(pfse->pfse_m, pfse->pfse_icmp_type, + pfse->pfse_icmp_code, 0, pfse->pfse_icmp_mtu); + break; +#endif /* INET */ +#ifdef INET6 + case PFSE_IP6: + ip6_output(pfse->pfse_m, NULL, NULL, 0, NULL, NULL, + NULL); + break; + case PFSE_ICMP6: + icmp6_error(pfse->pfse_m, pfse->pfse_icmp_type, + pfse->pfse_icmp_code, pfse->pfse_icmp_mtu); + break; +#endif /* INET6 */ + default: + panic("%s: unknown type", __func__); + } + free(pfse, M_PFTEMP); + } + CURVNET_RESTORE(); +} + +void +pf_purge_thread(void *v) +{ + int fullrun; + + CURVNET_SET((struct vnet *)v); + + for (;;) { + PF_RULES_RLOCK(); + rw_sleep(pf_purge_thread, &pf_rules_lock, 0, "pftm", hz / 10); + + if (V_pf_end_threads) { + /* + * To cleanse up all kifs and rules we need + * two runs: first one clears reference flags, + * then pf_purge_expired_states() doesn't + * raise them, and then second run frees. + */ + PF_RULES_RUNLOCK(); + pf_purge_unlinked_rules(); + pfi_kif_purge(); + + /* + * Now purge everything. + */ + pf_purge_expired_states(V_pf_hashmask + 1); + pf_purge_expired_fragments(); + pf_purge_expired_src_nodes(); + + /* + * Now all kifs & rules should be unreferenced, + * thus should be successfully freed. + */ + pf_purge_unlinked_rules(); + pfi_kif_purge(); + + /* + * Announce success and exit. + */ + PF_RULES_RLOCK(); + V_pf_end_threads++; + PF_RULES_RUNLOCK(); + wakeup(pf_purge_thread); + kproc_exit(0); + } + PF_RULES_RUNLOCK(); + + /* Process 1/interval fraction of the state table every run. */ + fullrun = pf_purge_expired_states(V_pf_hashmask / + (V_pf_default_rule.timeout[PFTM_INTERVAL] * 10)); + + /* Purge other expired types every PFTM_INTERVAL seconds. */ + if (fullrun) { + /* + * Order is important: + * - states and src nodes reference rules + * - states and rules reference kifs + */ + pf_purge_expired_fragments(); + pf_purge_expired_src_nodes(); + pf_purge_unlinked_rules(); + pfi_kif_purge(); + } + } + /* not reached */ + CURVNET_RESTORE(); +} + +u_int32_t +pf_state_expires(const struct pf_state *state) +{ + u_int32_t timeout; + u_int32_t start; + u_int32_t end; + u_int32_t states; + + /* handle all PFTM_* > PFTM_MAX here */ + if (state->timeout == PFTM_PURGE) + return (time_uptime); + if (state->timeout == PFTM_UNTIL_PACKET) + return (0); + KASSERT(state->timeout != PFTM_UNLINKED, + ("pf_state_expires: timeout == PFTM_UNLINKED")); + KASSERT((state->timeout < PFTM_MAX), + ("pf_state_expires: timeout > PFTM_MAX")); + timeout = state->rule.ptr->timeout[state->timeout]; + if (!timeout) + timeout = V_pf_default_rule.timeout[state->timeout]; + start = state->rule.ptr->timeout[PFTM_ADAPTIVE_START]; + if (start) { + end = state->rule.ptr->timeout[PFTM_ADAPTIVE_END]; + states = state->rule.ptr->states_cur; /* XXXGL */ + } else { + start = V_pf_default_rule.timeout[PFTM_ADAPTIVE_START]; + end = V_pf_default_rule.timeout[PFTM_ADAPTIVE_END]; + states = V_pf_status.states; + } + if (end && states > start && start < end) { + if (states < end) + return (state->expire + timeout * (end - states) / + (end - start)); + else + return (time_uptime); + } + return (state->expire + timeout); +} + +void +pf_purge_expired_src_nodes() +{ + struct pf_srchash *sh; + struct pf_src_node *cur, *next; + int i; + + for (i = 0, sh = V_pf_srchash; i <= V_pf_srchashmask; i++, sh++) { + PF_HASHROW_LOCK(sh); + LIST_FOREACH_SAFE(cur, &sh->nodes, entry, next) + if (cur->states <= 0 && cur->expire <= time_uptime) { + if (cur->rule.ptr != NULL) + cur->rule.ptr->src_nodes--; + LIST_REMOVE(cur, entry); + V_pf_status.scounters[SCNT_SRC_NODE_REMOVALS]++; + V_pf_status.src_nodes--; + uma_zfree(V_pf_sources_z, cur); + } else if (cur->rule.ptr != NULL) + cur->rule.ptr->rule_flag |= PFRULE_REFS; + PF_HASHROW_UNLOCK(sh); + } +} + +static void +pf_src_tree_remove_state(struct pf_state *s) +{ + u_int32_t timeout; + + if (s->src_node != NULL) { + if (s->src.tcp_est) + --s->src_node->conn; + if (--s->src_node->states <= 0) { + timeout = s->rule.ptr->timeout[PFTM_SRC_NODE]; + if (!timeout) + timeout = + V_pf_default_rule.timeout[PFTM_SRC_NODE]; + s->src_node->expire = time_uptime + timeout; + } + } + if (s->nat_src_node != s->src_node && s->nat_src_node != NULL) { + if (--s->nat_src_node->states <= 0) { + timeout = s->rule.ptr->timeout[PFTM_SRC_NODE]; + if (!timeout) + timeout = + V_pf_default_rule.timeout[PFTM_SRC_NODE]; + s->nat_src_node->expire = time_uptime + timeout; + } + } + s->src_node = s->nat_src_node = NULL; +} + +/* + * Unlink and potentilly free a state. Function may be + * called with ID hash row locked, but always returns + * unlocked, since it needs to go through key hash locking. + */ +int +pf_unlink_state(struct pf_state *s, u_int flags) +{ + struct pf_idhash *ih = &V_pf_idhash[PF_IDHASH(s)]; + + if ((flags & PF_ENTER_LOCKED) == 0) + PF_HASHROW_LOCK(ih); + else + PF_HASHROW_ASSERT(ih); + + if (s->timeout == PFTM_UNLINKED) { + /* + * State is being processed + * by pf_unlink_state() in + * an other thread. + */ + PF_HASHROW_UNLOCK(ih); + return (0); /* XXXGL: undefined actually */ + } + + s->timeout = PFTM_UNLINKED; + + if (s->src.state == PF_TCPS_PROXY_DST) { + /* XXX wire key the right one? */ + pf_send_tcp(NULL, s->rule.ptr, s->key[PF_SK_WIRE]->af, + &s->key[PF_SK_WIRE]->addr[1], + &s->key[PF_SK_WIRE]->addr[0], + s->key[PF_SK_WIRE]->port[1], + s->key[PF_SK_WIRE]->port[0], + s->src.seqhi, s->src.seqlo + 1, + TH_RST|TH_ACK, 0, 0, 0, 1, s->tag, NULL); + } + + LIST_REMOVE(s, entry); + pf_src_tree_remove_state(s); + PF_HASHROW_UNLOCK(ih); + + if (pfsync_delete_state_ptr != NULL) + pfsync_delete_state_ptr(s); + + pf_detach_state(s); + refcount_release(&s->refs); + + return (pf_release_state(s)); +} + +void +pf_free_state(struct pf_state *cur) +{ + + KASSERT(cur->refs == 0, ("%s: %p has refs", __func__, cur)); + KASSERT(cur->timeout == PFTM_UNLINKED, ("%s: timeout %u", __func__, + cur->timeout)); + --cur->rule.ptr->states_cur; + if (cur->nat_rule.ptr != NULL) + --cur->nat_rule.ptr->states_cur; + if (cur->anchor.ptr != NULL) + --cur->anchor.ptr->states_cur; + pf_normalize_tcp_cleanup(cur); + uma_zfree(V_pf_state_z, cur); + V_pf_status.fcounters[FCNT_STATE_REMOVALS]++; +} + +/* + * Called only from pf_purge_thread(), thus serialized. + */ +static int +pf_purge_expired_states(int maxcheck) +{ + static u_int i = 0; + + struct pf_idhash *ih; + struct pf_state *s; + int rv = 0; + + V_pf_status.states = uma_zone_get_cur(V_pf_state_z); + + /* + * Go through hash and unlink states that expire now. + */ + while (maxcheck > 0) { + + /* Wrap to start of hash when we hit the end. */ + if (i > V_pf_hashmask) { + i = 0; + rv = 1; + } + + ih = &V_pf_idhash[i]; +relock: + PF_HASHROW_LOCK(ih); + LIST_FOREACH(s, &ih->states, entry) { + if (pf_state_expires(s) <= time_uptime) { + V_pf_status.states -= + pf_unlink_state(s, PF_ENTER_LOCKED); + goto relock; + } + s->rule.ptr->rule_flag |= PFRULE_REFS; + if (s->nat_rule.ptr != NULL) + s->nat_rule.ptr->rule_flag |= PFRULE_REFS; + if (s->anchor.ptr != NULL) + s->anchor.ptr->rule_flag |= PFRULE_REFS; + s->kif->pfik_flags |= PFI_IFLAG_REFS; + if (s->rt_kif) + s->rt_kif->pfik_flags |= PFI_IFLAG_REFS; + } + PF_HASHROW_UNLOCK(ih); + i++; + maxcheck--; + } + + V_pf_status.states = uma_zone_get_cur(V_pf_state_z); + + return (rv); +} + +static void +pf_purge_unlinked_rules() +{ + struct pf_rulequeue tmpq; + struct pf_rule *r, *r1; + + /* + * Do naive mark-and-sweep garbage collecting of old rules. + * Reference flag is raised by pf_purge_expired_states() + * and pf_purge_expired_src_nodes(). + * + * To avoid LOR between PF_UNLNKDRULES_LOCK/PF_RULES_WLOCK, + * use a temporary queue. + */ + TAILQ_INIT(&tmpq); + PF_UNLNKDRULES_LOCK(); + TAILQ_FOREACH_SAFE(r, &V_pf_unlinked_rules, entries, r1) { + if (!(r->rule_flag & PFRULE_REFS)) { + TAILQ_REMOVE(&V_pf_unlinked_rules, r, entries); + TAILQ_INSERT_TAIL(&tmpq, r, entries); + } else + r->rule_flag &= ~PFRULE_REFS; + } + PF_UNLNKDRULES_UNLOCK(); + + if (!TAILQ_EMPTY(&tmpq)) { + PF_RULES_WLOCK(); + TAILQ_FOREACH_SAFE(r, &tmpq, entries, r1) { + TAILQ_REMOVE(&tmpq, r, entries); + pf_free_rule(r); + } + PF_RULES_WUNLOCK(); + } +} + +void +pf_print_host(struct pf_addr *addr, u_int16_t p, sa_family_t af) +{ + switch (af) { +#ifdef INET + case AF_INET: { + u_int32_t a = ntohl(addr->addr32[0]); + printf("%u.%u.%u.%u", (a>>24)&255, (a>>16)&255, + (a>>8)&255, a&255); + if (p) { + p = ntohs(p); + printf(":%u", p); + } + break; + } +#endif /* INET */ +#ifdef INET6 + case AF_INET6: { + u_int16_t b; + u_int8_t i, curstart, curend, maxstart, maxend; + curstart = curend = maxstart = maxend = 255; + for (i = 0; i < 8; i++) { + if (!addr->addr16[i]) { + if (curstart == 255) + curstart = i; + curend = i; + } else { + if ((curend - curstart) > + (maxend - maxstart)) { + maxstart = curstart; + maxend = curend; + } + curstart = curend = 255; + } + } + if ((curend - curstart) > + (maxend - maxstart)) { + maxstart = curstart; + maxend = curend; + } + for (i = 0; i < 8; i++) { + if (i >= maxstart && i <= maxend) { + if (i == 0) + printf(":"); + if (i == maxend) + printf(":"); + } else { + b = ntohs(addr->addr16[i]); + printf("%x", b); + if (i < 7) + printf(":"); + } + } + if (p) { + p = ntohs(p); + printf("[%u]", p); + } + break; + } +#endif /* INET6 */ + } +} + +void +pf_print_state(struct pf_state *s) +{ + pf_print_state_parts(s, NULL, NULL); +} + +static void +pf_print_state_parts(struct pf_state *s, + struct pf_state_key *skwp, struct pf_state_key *sksp) +{ + struct pf_state_key *skw, *sks; + u_int8_t proto, dir; + + /* Do our best to fill these, but they're skipped if NULL */ + skw = skwp ? skwp : (s ? s->key[PF_SK_WIRE] : NULL); + sks = sksp ? sksp : (s ? s->key[PF_SK_STACK] : NULL); + proto = skw ? skw->proto : (sks ? sks->proto : 0); + dir = s ? s->direction : 0; + + switch (proto) { + case IPPROTO_IPV4: + printf("IPv4"); + break; + case IPPROTO_IPV6: + printf("IPv6"); + break; + case IPPROTO_TCP: + printf("TCP"); + break; + case IPPROTO_UDP: + printf("UDP"); + break; + case IPPROTO_ICMP: + printf("ICMP"); + break; + case IPPROTO_ICMPV6: + printf("ICMPv6"); + break; + default: + printf("%u", skw->proto); + break; + } + switch (dir) { + case PF_IN: + printf(" in"); + break; + case PF_OUT: + printf(" out"); + break; + } + if (skw) { + printf(" wire: "); + pf_print_host(&skw->addr[0], skw->port[0], skw->af); + printf(" "); + pf_print_host(&skw->addr[1], skw->port[1], skw->af); + } + if (sks) { + printf(" stack: "); + if (sks != skw) { + pf_print_host(&sks->addr[0], sks->port[0], sks->af); + printf(" "); + pf_print_host(&sks->addr[1], sks->port[1], sks->af); + } else + printf("-"); + } + if (s) { + if (proto == IPPROTO_TCP) { + printf(" [lo=%u high=%u win=%u modulator=%u", + s->src.seqlo, s->src.seqhi, + s->src.max_win, s->src.seqdiff); + if (s->src.wscale && s->dst.wscale) + printf(" wscale=%u", + s->src.wscale & PF_WSCALE_MASK); + printf("]"); + printf(" [lo=%u high=%u win=%u modulator=%u", + s->dst.seqlo, s->dst.seqhi, + s->dst.max_win, s->dst.seqdiff); + if (s->src.wscale && s->dst.wscale) + printf(" wscale=%u", + s->dst.wscale & PF_WSCALE_MASK); + printf("]"); + } + printf(" %u:%u", s->src.state, s->dst.state); + } +} + +void +pf_print_flags(u_int8_t f) +{ + if (f) + printf(" "); + if (f & TH_FIN) + printf("F"); + if (f & TH_SYN) + printf("S"); + if (f & TH_RST) + printf("R"); + if (f & TH_PUSH) + printf("P"); + if (f & TH_ACK) + printf("A"); + if (f & TH_URG) + printf("U"); + if (f & TH_ECE) + printf("E"); + if (f & TH_CWR) + printf("W"); +} + +#define PF_SET_SKIP_STEPS(i) \ + do { \ + while (head[i] != cur) { \ + head[i]->skip[i].ptr = cur; \ + head[i] = TAILQ_NEXT(head[i], entries); \ + } \ + } while (0) + +void +pf_calc_skip_steps(struct pf_rulequeue *rules) +{ + struct pf_rule *cur, *prev, *head[PF_SKIP_COUNT]; + int i; + + cur = TAILQ_FIRST(rules); + prev = cur; + for (i = 0; i < PF_SKIP_COUNT; ++i) + head[i] = cur; + while (cur != NULL) { + + if (cur->kif != prev->kif || cur->ifnot != prev->ifnot) + PF_SET_SKIP_STEPS(PF_SKIP_IFP); + if (cur->direction != prev->direction) + PF_SET_SKIP_STEPS(PF_SKIP_DIR); + if (cur->af != prev->af) + PF_SET_SKIP_STEPS(PF_SKIP_AF); + if (cur->proto != prev->proto) + PF_SET_SKIP_STEPS(PF_SKIP_PROTO); + if (cur->src.neg != prev->src.neg || + pf_addr_wrap_neq(&cur->src.addr, &prev->src.addr)) + PF_SET_SKIP_STEPS(PF_SKIP_SRC_ADDR); + if (cur->src.port[0] != prev->src.port[0] || + cur->src.port[1] != prev->src.port[1] || + cur->src.port_op != prev->src.port_op) + PF_SET_SKIP_STEPS(PF_SKIP_SRC_PORT); + if (cur->dst.neg != prev->dst.neg || + pf_addr_wrap_neq(&cur->dst.addr, &prev->dst.addr)) + PF_SET_SKIP_STEPS(PF_SKIP_DST_ADDR); + if (cur->dst.port[0] != prev->dst.port[0] || + cur->dst.port[1] != prev->dst.port[1] || + cur->dst.port_op != prev->dst.port_op) + PF_SET_SKIP_STEPS(PF_SKIP_DST_PORT); + + prev = cur; + cur = TAILQ_NEXT(cur, entries); + } + for (i = 0; i < PF_SKIP_COUNT; ++i) + PF_SET_SKIP_STEPS(i); +} + +static int +pf_addr_wrap_neq(struct pf_addr_wrap *aw1, struct pf_addr_wrap *aw2) +{ + if (aw1->type != aw2->type) + return (1); + switch (aw1->type) { + case PF_ADDR_ADDRMASK: + case PF_ADDR_RANGE: + if (PF_ANEQ(&aw1->v.a.addr, &aw2->v.a.addr, 0)) + return (1); + if (PF_ANEQ(&aw1->v.a.mask, &aw2->v.a.mask, 0)) + return (1); + return (0); + case PF_ADDR_DYNIFTL: + return (aw1->p.dyn->pfid_kt != aw2->p.dyn->pfid_kt); + case PF_ADDR_NOROUTE: + case PF_ADDR_URPFFAILED: + return (0); + case PF_ADDR_TABLE: + return (aw1->p.tbl != aw2->p.tbl); + default: + printf("invalid address type: %d\n", aw1->type); + return (1); + } +} + +u_int16_t +pf_cksum_fixup(u_int16_t cksum, u_int16_t old, u_int16_t new, u_int8_t udp) +{ + u_int32_t l; + + if (udp && !cksum) + return (0x0000); + l = cksum + old - new; + l = (l >> 16) + (l & 65535); + l = l & 65535; + if (udp && !l) + return (0xFFFF); + return (l); +} + +static void +pf_change_ap(struct pf_addr *a, u_int16_t *p, u_int16_t *ic, u_int16_t *pc, + struct pf_addr *an, u_int16_t pn, u_int8_t u, sa_family_t af) +{ + struct pf_addr ao; + u_int16_t po = *p; + + PF_ACPY(&ao, a, af); + PF_ACPY(a, an, af); + + *p = pn; + + switch (af) { +#ifdef INET + case AF_INET: + *ic = pf_cksum_fixup(pf_cksum_fixup(*ic, + ao.addr16[0], an->addr16[0], 0), + ao.addr16[1], an->addr16[1], 0); + *p = pn; + *pc = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(*pc, + ao.addr16[0], an->addr16[0], u), + ao.addr16[1], an->addr16[1], u), + po, pn, u); + break; +#endif /* INET */ +#ifdef INET6 + case AF_INET6: + *pc = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup( + pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup( + pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(*pc, + ao.addr16[0], an->addr16[0], u), + ao.addr16[1], an->addr16[1], u), + ao.addr16[2], an->addr16[2], u), + ao.addr16[3], an->addr16[3], u), + ao.addr16[4], an->addr16[4], u), + ao.addr16[5], an->addr16[5], u), + ao.addr16[6], an->addr16[6], u), + ao.addr16[7], an->addr16[7], u), + po, pn, u); + break; +#endif /* INET6 */ + } +} + + +/* Changes a u_int32_t. Uses a void * so there are no align restrictions */ +void +pf_change_a(void *a, u_int16_t *c, u_int32_t an, u_int8_t u) +{ + u_int32_t ao; + + memcpy(&ao, a, sizeof(ao)); + memcpy(a, &an, sizeof(u_int32_t)); + *c = pf_cksum_fixup(pf_cksum_fixup(*c, ao / 65536, an / 65536, u), + ao % 65536, an % 65536, u); +} + +#ifdef INET6 +static void +pf_change_a6(struct pf_addr *a, u_int16_t *c, struct pf_addr *an, u_int8_t u) +{ + struct pf_addr ao; + + PF_ACPY(&ao, a, AF_INET6); + PF_ACPY(a, an, AF_INET6); + + *c = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup( + pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup( + pf_cksum_fixup(pf_cksum_fixup(*c, + ao.addr16[0], an->addr16[0], u), + ao.addr16[1], an->addr16[1], u), + ao.addr16[2], an->addr16[2], u), + ao.addr16[3], an->addr16[3], u), + ao.addr16[4], an->addr16[4], u), + ao.addr16[5], an->addr16[5], u), + ao.addr16[6], an->addr16[6], u), + ao.addr16[7], an->addr16[7], u); +} +#endif /* INET6 */ + +static void +pf_change_icmp(struct pf_addr *ia, u_int16_t *ip, struct pf_addr *oa, + struct pf_addr *na, u_int16_t np, u_int16_t *pc, u_int16_t *h2c, + u_int16_t *ic, u_int16_t *hc, u_int8_t u, sa_family_t af) +{ + struct pf_addr oia, ooa; + + PF_ACPY(&oia, ia, af); + if (oa) + PF_ACPY(&ooa, oa, af); + + /* Change inner protocol port, fix inner protocol checksum. */ + if (ip != NULL) { + u_int16_t oip = *ip; + u_int32_t opc; + + if (pc != NULL) + opc = *pc; + *ip = np; + if (pc != NULL) + *pc = pf_cksum_fixup(*pc, oip, *ip, u); + *ic = pf_cksum_fixup(*ic, oip, *ip, 0); + if (pc != NULL) + *ic = pf_cksum_fixup(*ic, opc, *pc, 0); + } + /* Change inner ip address, fix inner ip and icmp checksums. */ + PF_ACPY(ia, na, af); + switch (af) { +#ifdef INET + case AF_INET: { + u_int32_t oh2c = *h2c; + + *h2c = pf_cksum_fixup(pf_cksum_fixup(*h2c, + oia.addr16[0], ia->addr16[0], 0), + oia.addr16[1], ia->addr16[1], 0); + *ic = pf_cksum_fixup(pf_cksum_fixup(*ic, + oia.addr16[0], ia->addr16[0], 0), + oia.addr16[1], ia->addr16[1], 0); + *ic = pf_cksum_fixup(*ic, oh2c, *h2c, 0); + break; + } +#endif /* INET */ +#ifdef INET6 + case AF_INET6: + *ic = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup( + pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup( + pf_cksum_fixup(pf_cksum_fixup(*ic, + oia.addr16[0], ia->addr16[0], u), + oia.addr16[1], ia->addr16[1], u), + oia.addr16[2], ia->addr16[2], u), + oia.addr16[3], ia->addr16[3], u), + oia.addr16[4], ia->addr16[4], u), + oia.addr16[5], ia->addr16[5], u), + oia.addr16[6], ia->addr16[6], u), + oia.addr16[7], ia->addr16[7], u); + break; +#endif /* INET6 */ + } + /* Outer ip address, fix outer ip or icmpv6 checksum, if necessary. */ + if (oa) { + PF_ACPY(oa, na, af); + switch (af) { +#ifdef INET + case AF_INET: + *hc = pf_cksum_fixup(pf_cksum_fixup(*hc, + ooa.addr16[0], oa->addr16[0], 0), + ooa.addr16[1], oa->addr16[1], 0); + break; +#endif /* INET */ +#ifdef INET6 + case AF_INET6: + *ic = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup( + pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup( + pf_cksum_fixup(pf_cksum_fixup(*ic, + ooa.addr16[0], oa->addr16[0], u), + ooa.addr16[1], oa->addr16[1], u), + ooa.addr16[2], oa->addr16[2], u), + ooa.addr16[3], oa->addr16[3], u), + ooa.addr16[4], oa->addr16[4], u), + ooa.addr16[5], oa->addr16[5], u), + ooa.addr16[6], oa->addr16[6], u), + ooa.addr16[7], oa->addr16[7], u); + break; +#endif /* INET6 */ + } + } +} + + +/* + * Need to modulate the sequence numbers in the TCP SACK option + * (credits to Krzysztof Pfaff for report and patch) + */ +static int +pf_modulate_sack(struct mbuf *m, int off, struct pf_pdesc *pd, + struct tcphdr *th, struct pf_state_peer *dst) +{ + int hlen = (th->th_off << 2) - sizeof(*th), thoptlen = hlen; + u_int8_t opts[TCP_MAXOLEN], *opt = opts; + int copyback = 0, i, olen; + struct sackblk sack; + +#define TCPOLEN_SACKLEN (TCPOLEN_SACK + 2) + if (hlen < TCPOLEN_SACKLEN || + !pf_pull_hdr(m, off + sizeof(*th), opts, hlen, NULL, NULL, pd->af)) + return 0; + + while (hlen >= TCPOLEN_SACKLEN) { + olen = opt[1]; + switch (*opt) { + case TCPOPT_EOL: /* FALLTHROUGH */ + case TCPOPT_NOP: + opt++; + hlen--; + break; + case TCPOPT_SACK: + if (olen > hlen) + olen = hlen; + if (olen >= TCPOLEN_SACKLEN) { + for (i = 2; i + TCPOLEN_SACK <= olen; + i += TCPOLEN_SACK) { + memcpy(&sack, &opt[i], sizeof(sack)); + pf_change_a(&sack.start, &th->th_sum, + htonl(ntohl(sack.start) - + dst->seqdiff), 0); + pf_change_a(&sack.end, &th->th_sum, + htonl(ntohl(sack.end) - + dst->seqdiff), 0); + memcpy(&opt[i], &sack, sizeof(sack)); + } + copyback = 1; + } + /* FALLTHROUGH */ + default: + if (olen < 2) + olen = 2; + hlen -= olen; + opt += olen; + } + } + + if (copyback) + m_copyback(m, off + sizeof(*th), thoptlen, (caddr_t)opts); + return (copyback); +} + +static void +pf_send_tcp(struct mbuf *replyto, const struct pf_rule *r, sa_family_t af, + const struct pf_addr *saddr, const struct pf_addr *daddr, + u_int16_t sport, u_int16_t dport, u_int32_t seq, u_int32_t ack, + u_int8_t flags, u_int16_t win, u_int16_t mss, u_int8_t ttl, int tag, + u_int16_t rtag, struct ifnet *ifp) +{ + struct pf_send_entry *pfse; + struct mbuf *m; + int len, tlen; +#ifdef INET + struct ip *h = NULL; +#endif /* INET */ +#ifdef INET6 + struct ip6_hdr *h6 = NULL; +#endif /* INET6 */ + struct tcphdr *th; + char *opt; + struct pf_mtag *pf_mtag; + + len = 0; + th = NULL; + + /* maximum segment size tcp option */ + tlen = sizeof(struct tcphdr); + if (mss) + tlen += 4; + + switch (af) { +#ifdef INET + case AF_INET: + len = sizeof(struct ip) + tlen; + break; +#endif /* INET */ +#ifdef INET6 + case AF_INET6: + len = sizeof(struct ip6_hdr) + tlen; + break; +#endif /* INET6 */ + default: + panic("%s: unsupported af %d", __func__, af); + } + + /* Allocate outgoing queue entry, mbuf and mbuf tag. */ + pfse = malloc(sizeof(*pfse), M_PFTEMP, M_NOWAIT); + if (pfse == NULL) + return; + m = m_gethdr(M_NOWAIT, MT_HEADER); + if (m == NULL) { + free(pfse, M_PFTEMP); + return; + } +#ifdef MAC + mac_netinet_firewall_send(m); +#endif + if ((pf_mtag = pf_get_mtag(m)) == NULL) { + free(pfse, M_PFTEMP); + m_freem(m); + return; + } + if (tag) + m->m_flags |= M_SKIP_FIREWALL; + pf_mtag->tag = rtag; + + if (r != NULL && r->rtableid >= 0) + M_SETFIB(m, r->rtableid); + +#ifdef ALTQ + if (r != NULL && r->qid) { + pf_mtag->qid = r->qid; + + /* add hints for ecn */ + pf_mtag->hdr = mtod(m, struct ip *); + } +#endif /* ALTQ */ + m->m_data += max_linkhdr; + m->m_pkthdr.len = m->m_len = len; + m->m_pkthdr.rcvif = NULL; + bzero(m->m_data, len); + switch (af) { +#ifdef INET + case AF_INET: + h = mtod(m, struct ip *); + + /* IP header fields included in the TCP checksum */ + h->ip_p = IPPROTO_TCP; + h->ip_len = htons(tlen); + h->ip_src.s_addr = saddr->v4.s_addr; + h->ip_dst.s_addr = daddr->v4.s_addr; + + th = (struct tcphdr *)((caddr_t)h + sizeof(struct ip)); + break; +#endif /* INET */ +#ifdef INET6 + case AF_INET6: + h6 = mtod(m, struct ip6_hdr *); + + /* IP header fields included in the TCP checksum */ + h6->ip6_nxt = IPPROTO_TCP; + h6->ip6_plen = htons(tlen); + memcpy(&h6->ip6_src, &saddr->v6, sizeof(struct in6_addr)); + memcpy(&h6->ip6_dst, &daddr->v6, sizeof(struct in6_addr)); + + th = (struct tcphdr *)((caddr_t)h6 + sizeof(struct ip6_hdr)); + break; +#endif /* INET6 */ + } + + /* TCP header */ + th->th_sport = sport; + th->th_dport = dport; + th->th_seq = htonl(seq); + th->th_ack = htonl(ack); + th->th_off = tlen >> 2; + th->th_flags = flags; + th->th_win = htons(win); + + if (mss) { + opt = (char *)(th + 1); + opt[0] = TCPOPT_MAXSEG; + opt[1] = 4; + HTONS(mss); + bcopy((caddr_t)&mss, (caddr_t)(opt + 2), 2); + } + + switch (af) { +#ifdef INET + case AF_INET: + /* TCP checksum */ + th->th_sum = in_cksum(m, len); + + /* Finish the IP header */ + h->ip_v = 4; + h->ip_hl = sizeof(*h) >> 2; + h->ip_tos = IPTOS_LOWDELAY; + h->ip_off = V_path_mtu_discovery ? IP_DF : 0; + h->ip_len = len; + h->ip_ttl = ttl ? ttl : V_ip_defttl; + h->ip_sum = 0; + + pfse->pfse_type = PFSE_IP; + break; +#endif /* INET */ +#ifdef INET6 + case AF_INET6: + /* TCP checksum */ + th->th_sum = in6_cksum(m, IPPROTO_TCP, + sizeof(struct ip6_hdr), tlen); + + h6->ip6_vfc |= IPV6_VERSION; + h6->ip6_hlim = IPV6_DEFHLIM; + + pfse->pfse_type = PFSE_IP6; + break; +#endif /* INET6 */ + } + pfse->pfse_m = m; + pf_send(pfse); +} + +static void +pf_send_icmp(struct mbuf *m, u_int8_t type, u_int8_t code, sa_family_t af, + struct pf_rule *r) +{ + struct pf_send_entry *pfse; + struct mbuf *m0; + struct pf_mtag *pf_mtag; + + /* Allocate outgoing queue entry, mbuf and mbuf tag. */ + pfse = malloc(sizeof(*pfse), M_PFTEMP, M_NOWAIT); + if (pfse == NULL) + return; + + if ((m0 = m_copypacket(m, M_NOWAIT)) == NULL) { + free(pfse, M_PFTEMP); + return; + } + + if ((pf_mtag = pf_get_mtag(m0)) == NULL) { + free(pfse, M_PFTEMP); + return; + } + /* XXX: revisit */ + m0->m_flags |= M_SKIP_FIREWALL; + + if (r->rtableid >= 0) + M_SETFIB(m0, r->rtableid); + +#ifdef ALTQ + if (r->qid) { + pf_mtag->qid = r->qid; + /* add hints for ecn */ + pf_mtag->hdr = mtod(m0, struct ip *); + } +#endif /* ALTQ */ + + switch (af) { +#ifdef INET + case AF_INET: + { + struct ip *ip; + + /* icmp_error() expects host byte ordering */ + ip = mtod(m0, struct ip *); + NTOHS(ip->ip_len); + NTOHS(ip->ip_off); + + pfse->pfse_type = PFSE_ICMP; + break; + } +#endif /* INET */ +#ifdef INET6 + case AF_INET6: + pfse->pfse_type = PFSE_ICMP6; + break; +#endif /* INET6 */ + } + pfse->pfse_m = m0; + pfse->pfse_icmp_type = type; + pfse->pfse_icmp_code = code; + pf_send(pfse); +} + +/* + * Return 1 if the addresses a and b match (with mask m), otherwise return 0. + * If n is 0, they match if they are equal. If n is != 0, they match if they + * are different. + */ +int +pf_match_addr(u_int8_t n, struct pf_addr *a, struct pf_addr *m, + struct pf_addr *b, sa_family_t af) +{ + int match = 0; + + switch (af) { +#ifdef INET + case AF_INET: + if ((a->addr32[0] & m->addr32[0]) == + (b->addr32[0] & m->addr32[0])) + match++; + break; +#endif /* INET */ +#ifdef INET6 + case AF_INET6: + if (((a->addr32[0] & m->addr32[0]) == + (b->addr32[0] & m->addr32[0])) && + ((a->addr32[1] & m->addr32[1]) == + (b->addr32[1] & m->addr32[1])) && + ((a->addr32[2] & m->addr32[2]) == + (b->addr32[2] & m->addr32[2])) && + ((a->addr32[3] & m->addr32[3]) == + (b->addr32[3] & m->addr32[3]))) + match++; + break; +#endif /* INET6 */ + } + if (match) { + if (n) + return (0); + else + return (1); + } else { + if (n) + return (1); + else + return (0); + } +} + +/* + * Return 1 if b <= a <= e, otherwise return 0. + */ +int +pf_match_addr_range(struct pf_addr *b, struct pf_addr *e, + struct pf_addr *a, sa_family_t af) +{ + switch (af) { +#ifdef INET + case AF_INET: + if ((a->addr32[0] < b->addr32[0]) || + (a->addr32[0] > e->addr32[0])) + return (0); + break; +#endif /* INET */ +#ifdef INET6 + case AF_INET6: { + int i; + + /* check a >= b */ + for (i = 0; i < 4; ++i) + if (a->addr32[i] > b->addr32[i]) + break; + else if (a->addr32[i] < b->addr32[i]) + return (0); + /* check a <= e */ + for (i = 0; i < 4; ++i) + if (a->addr32[i] < e->addr32[i]) + break; + else if (a->addr32[i] > e->addr32[i]) + return (0); + break; + } +#endif /* INET6 */ + } + return (1); +} + +static int +pf_match(u_int8_t op, u_int32_t a1, u_int32_t a2, u_int32_t p) +{ + switch (op) { + case PF_OP_IRG: + return ((p > a1) && (p < a2)); + case PF_OP_XRG: + return ((p < a1) || (p > a2)); + case PF_OP_RRG: + return ((p >= a1) && (p <= a2)); + case PF_OP_EQ: + return (p == a1); + case PF_OP_NE: + return (p != a1); + case PF_OP_LT: + return (p < a1); + case PF_OP_LE: + return (p <= a1); + case PF_OP_GT: + return (p > a1); + case PF_OP_GE: + return (p >= a1); + } + return (0); /* never reached */ +} + +int +pf_match_port(u_int8_t op, u_int16_t a1, u_int16_t a2, u_int16_t p) +{ + NTOHS(a1); + NTOHS(a2); + NTOHS(p); + return (pf_match(op, a1, a2, p)); +} + +static int +pf_match_uid(u_int8_t op, uid_t a1, uid_t a2, uid_t u) +{ + if (u == UID_MAX && op != PF_OP_EQ && op != PF_OP_NE) + return (0); + return (pf_match(op, a1, a2, u)); +} + +static int +pf_match_gid(u_int8_t op, gid_t a1, gid_t a2, gid_t g) +{ + if (g == GID_MAX && op != PF_OP_EQ && op != PF_OP_NE) + return (0); + return (pf_match(op, a1, a2, g)); +} + +int +pf_match_tag(struct mbuf *m, struct pf_rule *r, int *tag, int mtag) +{ + if (*tag == -1) + *tag = mtag; + + return ((!r->match_tag_not && r->match_tag == *tag) || + (r->match_tag_not && r->match_tag != *tag)); +} + +int +pf_tag_packet(struct mbuf *m, struct pf_pdesc *pd, int tag) +{ + + KASSERT(tag > 0, ("%s: tag %d", __func__, tag)); + + if (pd->pf_mtag == NULL && ((pd->pf_mtag = pf_get_mtag(m)) == NULL)) + return (ENOMEM); + + pd->pf_mtag->tag = tag; + + return (0); +} + +void +pf_step_into_anchor(int *depth, struct pf_ruleset **rs, int n, + struct pf_rule **r, struct pf_rule **a, int *match) +{ + struct pf_anchor_stackframe *f; + + PF_RULES_RASSERT(); + + (*r)->anchor->match = 0; + if (match) + *match = 0; + if (*depth >= sizeof(V_pf_anchor_stack) / + sizeof(V_pf_anchor_stack[0])) { + printf("pf_step_into_anchor: stack overflow\n"); + *r = TAILQ_NEXT(*r, entries); + return; + } else if (*depth == 0 && a != NULL) + *a = *r; + f = V_pf_anchor_stack + (*depth)++; + f->rs = *rs; + f->r = *r; + if ((*r)->anchor_wildcard) { + f->parent = &(*r)->anchor->children; + if ((f->child = RB_MIN(pf_anchor_node, f->parent)) == + NULL) { + *r = NULL; + return; + } + *rs = &f->child->ruleset; + } else { + f->parent = NULL; + f->child = NULL; + *rs = &(*r)->anchor->ruleset; + } + *r = TAILQ_FIRST((*rs)->rules[n].active.ptr); +} + +int +pf_step_out_of_anchor(int *depth, struct pf_ruleset **rs, int n, + struct pf_rule **r, struct pf_rule **a, int *match) +{ + struct pf_anchor_stackframe *f; + int quick = 0; + + PF_RULES_RASSERT(); + + do { + if (*depth <= 0) + break; + f = V_pf_anchor_stack + *depth - 1; + if (f->parent != NULL && f->child != NULL) { + if (f->child->match || + (match != NULL && *match)) { + f->r->anchor->match = 1; + *match = 0; + } + f->child = RB_NEXT(pf_anchor_node, f->parent, f->child); + if (f->child != NULL) { + *rs = &f->child->ruleset; + *r = TAILQ_FIRST((*rs)->rules[n].active.ptr); + if (*r == NULL) + continue; + else + break; + } + } + (*depth)--; + if (*depth == 0 && a != NULL) + *a = NULL; + *rs = f->rs; + if (f->r->anchor->match || (match != NULL && *match)) + quick = f->r->quick; + *r = TAILQ_NEXT(f->r, entries); + } while (*r == NULL); + + return (quick); +} + +#ifdef INET6 +void +pf_poolmask(struct pf_addr *naddr, struct pf_addr *raddr, + struct pf_addr *rmask, struct pf_addr *saddr, sa_family_t af) +{ + switch (af) { +#ifdef INET + case AF_INET: + naddr->addr32[0] = (raddr->addr32[0] & rmask->addr32[0]) | + ((rmask->addr32[0] ^ 0xffffffff ) & saddr->addr32[0]); + break; +#endif /* INET */ + case AF_INET6: + naddr->addr32[0] = (raddr->addr32[0] & rmask->addr32[0]) | + ((rmask->addr32[0] ^ 0xffffffff ) & saddr->addr32[0]); + naddr->addr32[1] = (raddr->addr32[1] & rmask->addr32[1]) | + ((rmask->addr32[1] ^ 0xffffffff ) & saddr->addr32[1]); + naddr->addr32[2] = (raddr->addr32[2] & rmask->addr32[2]) | + ((rmask->addr32[2] ^ 0xffffffff ) & saddr->addr32[2]); + naddr->addr32[3] = (raddr->addr32[3] & rmask->addr32[3]) | + ((rmask->addr32[3] ^ 0xffffffff ) & saddr->addr32[3]); + break; + } +} + +void +pf_addr_inc(struct pf_addr *addr, sa_family_t af) +{ + switch (af) { +#ifdef INET + case AF_INET: + addr->addr32[0] = htonl(ntohl(addr->addr32[0]) + 1); + break; +#endif /* INET */ + case AF_INET6: + if (addr->addr32[3] == 0xffffffff) { + addr->addr32[3] = 0; + if (addr->addr32[2] == 0xffffffff) { + addr->addr32[2] = 0; + if (addr->addr32[1] == 0xffffffff) { + addr->addr32[1] = 0; + addr->addr32[0] = + htonl(ntohl(addr->addr32[0]) + 1); + } else + addr->addr32[1] = + htonl(ntohl(addr->addr32[1]) + 1); + } else + addr->addr32[2] = + htonl(ntohl(addr->addr32[2]) + 1); + } else + addr->addr32[3] = + htonl(ntohl(addr->addr32[3]) + 1); + break; + } +} +#endif /* INET6 */ + +int +pf_socket_lookup(int direction, struct pf_pdesc *pd, struct mbuf *m) +{ + struct pf_addr *saddr, *daddr; + u_int16_t sport, dport; + struct inpcbinfo *pi; + struct inpcb *inp; + + pd->lookup.uid = UID_MAX; + pd->lookup.gid = GID_MAX; + + switch (pd->proto) { + case IPPROTO_TCP: + if (pd->hdr.tcp == NULL) + return (-1); + sport = pd->hdr.tcp->th_sport; + dport = pd->hdr.tcp->th_dport; + pi = &V_tcbinfo; + break; + case IPPROTO_UDP: + if (pd->hdr.udp == NULL) + return (-1); + sport = pd->hdr.udp->uh_sport; + dport = pd->hdr.udp->uh_dport; + pi = &V_udbinfo; + break; + default: + return (-1); + } + if (direction == PF_IN) { + saddr = pd->src; + daddr = pd->dst; + } else { + u_int16_t p; + + p = sport; + sport = dport; + dport = p; + saddr = pd->dst; + daddr = pd->src; + } + switch (pd->af) { +#ifdef INET + case AF_INET: + inp = in_pcblookup_mbuf(pi, saddr->v4, sport, daddr->v4, + dport, INPLOOKUP_RLOCKPCB, NULL, m); + if (inp == NULL) { + inp = in_pcblookup_mbuf(pi, saddr->v4, sport, + daddr->v4, dport, INPLOOKUP_WILDCARD | + INPLOOKUP_RLOCKPCB, NULL, m); + if (inp == NULL) + return (-1); + } + break; +#endif /* INET */ +#ifdef INET6 + case AF_INET6: + inp = in6_pcblookup_mbuf(pi, &saddr->v6, sport, &daddr->v6, + dport, INPLOOKUP_RLOCKPCB, NULL, m); + if (inp == NULL) { + inp = in6_pcblookup_mbuf(pi, &saddr->v6, sport, + &daddr->v6, dport, INPLOOKUP_WILDCARD | + INPLOOKUP_RLOCKPCB, NULL, m); + if (inp == NULL) + return (-1); + } + break; +#endif /* INET6 */ + + default: + return (-1); + } + INP_RLOCK_ASSERT(inp); + pd->lookup.uid = inp->inp_cred->cr_uid; + pd->lookup.gid = inp->inp_cred->cr_groups[0]; + INP_RUNLOCK(inp); + + return (1); +} + +static u_int8_t +pf_get_wscale(struct mbuf *m, int off, u_int16_t th_off, sa_family_t af) +{ + int hlen; + u_int8_t hdr[60]; + u_int8_t *opt, optlen; + u_int8_t wscale = 0; + + hlen = th_off << 2; /* hlen <= sizeof(hdr) */ + if (hlen <= sizeof(struct tcphdr)) + return (0); + if (!pf_pull_hdr(m, off, hdr, hlen, NULL, NULL, af)) + return (0); + opt = hdr + sizeof(struct tcphdr); + hlen -= sizeof(struct tcphdr); + while (hlen >= 3) { + switch (*opt) { + case TCPOPT_EOL: + case TCPOPT_NOP: + ++opt; + --hlen; + break; + case TCPOPT_WINDOW: + wscale = opt[2]; + if (wscale > TCP_MAX_WINSHIFT) + wscale = TCP_MAX_WINSHIFT; + wscale |= PF_WSCALE_FLAG; + /* FALLTHROUGH */ + default: + optlen = opt[1]; + if (optlen < 2) + optlen = 2; + hlen -= optlen; + opt += optlen; + break; + } + } + return (wscale); +} + +static u_int16_t +pf_get_mss(struct mbuf *m, int off, u_int16_t th_off, sa_family_t af) +{ + int hlen; + u_int8_t hdr[60]; + u_int8_t *opt, optlen; + u_int16_t mss = V_tcp_mssdflt; + + hlen = th_off << 2; /* hlen <= sizeof(hdr) */ + if (hlen <= sizeof(struct tcphdr)) + return (0); + if (!pf_pull_hdr(m, off, hdr, hlen, NULL, NULL, af)) + return (0); + opt = hdr + sizeof(struct tcphdr); + hlen -= sizeof(struct tcphdr); + while (hlen >= TCPOLEN_MAXSEG) { + switch (*opt) { + case TCPOPT_EOL: + case TCPOPT_NOP: + ++opt; + --hlen; + break; + case TCPOPT_MAXSEG: + bcopy((caddr_t)(opt + 2), (caddr_t)&mss, 2); + NTOHS(mss); + /* FALLTHROUGH */ + default: + optlen = opt[1]; + if (optlen < 2) + optlen = 2; + hlen -= optlen; + opt += optlen; + break; + } + } + return (mss); +} + +static u_int16_t +pf_calc_mss(struct pf_addr *addr, sa_family_t af, int rtableid, u_int16_t offer) +{ +#ifdef INET + struct sockaddr_in *dst; + struct route ro; +#endif /* INET */ +#ifdef INET6 + struct sockaddr_in6 *dst6; + struct route_in6 ro6; +#endif /* INET6 */ + struct rtentry *rt = NULL; + int hlen = 0; + u_int16_t mss = V_tcp_mssdflt; + + switch (af) { +#ifdef INET + case AF_INET: + hlen = sizeof(struct ip); + bzero(&ro, sizeof(ro)); + dst = (struct sockaddr_in *)&ro.ro_dst; + dst->sin_family = AF_INET; + dst->sin_len = sizeof(*dst); + dst->sin_addr = addr->v4; + in_rtalloc_ign(&ro, 0, rtableid); + rt = ro.ro_rt; + break; +#endif /* INET */ +#ifdef INET6 + case AF_INET6: + hlen = sizeof(struct ip6_hdr); + bzero(&ro6, sizeof(ro6)); + dst6 = (struct sockaddr_in6 *)&ro6.ro_dst; + dst6->sin6_family = AF_INET6; + dst6->sin6_len = sizeof(*dst6); + dst6->sin6_addr = addr->v6; + in6_rtalloc_ign(&ro6, 0, rtableid); + rt = ro6.ro_rt; + break; +#endif /* INET6 */ + } + + if (rt && rt->rt_ifp) { + mss = rt->rt_ifp->if_mtu - hlen - sizeof(struct tcphdr); + mss = max(V_tcp_mssdflt, mss); + RTFREE(rt); + } + mss = min(mss, offer); + mss = max(mss, 64); /* sanity - at least max opt space */ + return (mss); +} + +static void +pf_set_rt_ifp(struct pf_state *s, struct pf_addr *saddr) +{ + struct pf_rule *r = s->rule.ptr; + struct pf_src_node *sn = NULL; + + s->rt_kif = NULL; + if (!r->rt || r->rt == PF_FASTROUTE) + return; + switch (s->key[PF_SK_WIRE]->af) { +#ifdef INET + case AF_INET: + pf_map_addr(AF_INET, r, saddr, &s->rt_addr, NULL, &sn); + s->rt_kif = r->rpool.cur->kif; + break; +#endif /* INET */ +#ifdef INET6 + case AF_INET6: + pf_map_addr(AF_INET6, r, saddr, &s->rt_addr, NULL, &sn); + s->rt_kif = r->rpool.cur->kif; + break; +#endif /* INET6 */ + } +} + +static u_int32_t +pf_tcp_iss(struct pf_pdesc *pd) +{ + MD5_CTX ctx; + u_int32_t digest[4]; + + if (V_pf_tcp_secret_init == 0) { + read_random(&V_pf_tcp_secret, sizeof(V_pf_tcp_secret)); + MD5Init(&V_pf_tcp_secret_ctx); + MD5Update(&V_pf_tcp_secret_ctx, V_pf_tcp_secret, + sizeof(V_pf_tcp_secret)); + V_pf_tcp_secret_init = 1; + } + + ctx = V_pf_tcp_secret_ctx; + + MD5Update(&ctx, (char *)&pd->hdr.tcp->th_sport, sizeof(u_short)); + MD5Update(&ctx, (char *)&pd->hdr.tcp->th_dport, sizeof(u_short)); + if (pd->af == AF_INET6) { + MD5Update(&ctx, (char *)&pd->src->v6, sizeof(struct in6_addr)); + MD5Update(&ctx, (char *)&pd->dst->v6, sizeof(struct in6_addr)); + } else { + MD5Update(&ctx, (char *)&pd->src->v4, sizeof(struct in_addr)); + MD5Update(&ctx, (char *)&pd->dst->v4, sizeof(struct in_addr)); + } + MD5Final((u_char *)digest, &ctx); + V_pf_tcp_iss_off += 4096; +#define ISN_RANDOM_INCREMENT (4096 - 1) + return (digest[0] + (arc4random() & ISN_RANDOM_INCREMENT) + + V_pf_tcp_iss_off); +#undef ISN_RANDOM_INCREMENT +} + +static int +pf_test_rule(struct pf_rule **rm, struct pf_state **sm, int direction, + struct pfi_kif *kif, struct mbuf *m, int off, struct pf_pdesc *pd, + struct pf_rule **am, struct pf_ruleset **rsm, struct inpcb *inp) +{ + struct pf_rule *nr = NULL; + struct pf_addr * const saddr = pd->src; + struct pf_addr * const daddr = pd->dst; + sa_family_t af = pd->af; + struct pf_rule *r, *a = NULL; + struct pf_ruleset *ruleset = NULL; + struct pf_src_node *nsn = NULL; + struct tcphdr *th = pd->hdr.tcp; + struct pf_state_key *sk = NULL, *nk = NULL; + u_short reason; + int rewrite = 0, hdrlen = 0; + int tag = -1, rtableid = -1; + int asd = 0; + int match = 0; + int state_icmp = 0; + u_int16_t sport = 0, dport = 0; + u_int16_t bproto_sum = 0, bip_sum = 0; + u_int8_t icmptype = 0, icmpcode = 0; + + PF_RULES_RASSERT(); + + if (inp != NULL) { + INP_LOCK_ASSERT(inp); + pd->lookup.uid = inp->inp_cred->cr_uid; + pd->lookup.gid = inp->inp_cred->cr_groups[0]; + pd->lookup.done = 1; + } + + switch (pd->proto) { + case IPPROTO_TCP: + sport = th->th_sport; + dport = th->th_dport; + hdrlen = sizeof(*th); + break; + case IPPROTO_UDP: + sport = pd->hdr.udp->uh_sport; + dport = pd->hdr.udp->uh_dport; + hdrlen = sizeof(*pd->hdr.udp); + break; +#ifdef INET + case IPPROTO_ICMP: + if (pd->af != AF_INET) + break; + sport = dport = pd->hdr.icmp->icmp_id; + hdrlen = sizeof(*pd->hdr.icmp); + icmptype = pd->hdr.icmp->icmp_type; + icmpcode = pd->hdr.icmp->icmp_code; + + if (icmptype == ICMP_UNREACH || + icmptype == ICMP_SOURCEQUENCH || + icmptype == ICMP_REDIRECT || + icmptype == ICMP_TIMXCEED || + icmptype == ICMP_PARAMPROB) + state_icmp++; + break; +#endif /* INET */ +#ifdef INET6 + case IPPROTO_ICMPV6: + if (af != AF_INET6) + break; + sport = dport = pd->hdr.icmp6->icmp6_id; + hdrlen = sizeof(*pd->hdr.icmp6); + icmptype = pd->hdr.icmp6->icmp6_type; + icmpcode = pd->hdr.icmp6->icmp6_code; + + if (icmptype == ICMP6_DST_UNREACH || + icmptype == ICMP6_PACKET_TOO_BIG || + icmptype == ICMP6_TIME_EXCEEDED || + icmptype == ICMP6_PARAM_PROB) + state_icmp++; + break; +#endif /* INET6 */ + default: + sport = dport = hdrlen = 0; + break; + } + + r = TAILQ_FIRST(pf_main_ruleset.rules[PF_RULESET_FILTER].active.ptr); + + /* check packet for BINAT/NAT/RDR */ + if ((nr = pf_get_translation(pd, m, off, direction, kif, &nsn, &sk, + &nk, saddr, daddr, sport, dport)) != NULL) { + KASSERT(sk != NULL, ("%s: null sk", __func__)); + KASSERT(nk != NULL, ("%s: null nk", __func__)); + + if (pd->ip_sum) + bip_sum = *pd->ip_sum; + + switch (pd->proto) { + case IPPROTO_TCP: + bproto_sum = th->th_sum; + pd->proto_sum = &th->th_sum; + + if (PF_ANEQ(saddr, &nk->addr[pd->sidx], af) || + nk->port[pd->sidx] != sport) { + pf_change_ap(saddr, &th->th_sport, pd->ip_sum, + &th->th_sum, &nk->addr[pd->sidx], + nk->port[pd->sidx], 0, af); + pd->sport = &th->th_sport; + sport = th->th_sport; + } + + if (PF_ANEQ(daddr, &nk->addr[pd->didx], af) || + nk->port[pd->didx] != dport) { + pf_change_ap(daddr, &th->th_dport, pd->ip_sum, + &th->th_sum, &nk->addr[pd->didx], + nk->port[pd->didx], 0, af); + dport = th->th_dport; + pd->dport = &th->th_dport; + } + rewrite++; + break; + case IPPROTO_UDP: + bproto_sum = pd->hdr.udp->uh_sum; + pd->proto_sum = &pd->hdr.udp->uh_sum; + + if (PF_ANEQ(saddr, &nk->addr[pd->sidx], af) || + nk->port[pd->sidx] != sport) { + pf_change_ap(saddr, &pd->hdr.udp->uh_sport, + pd->ip_sum, &pd->hdr.udp->uh_sum, + &nk->addr[pd->sidx], + nk->port[pd->sidx], 1, af); + sport = pd->hdr.udp->uh_sport; + pd->sport = &pd->hdr.udp->uh_sport; + } + + if (PF_ANEQ(daddr, &nk->addr[pd->didx], af) || + nk->port[pd->didx] != dport) { + pf_change_ap(daddr, &pd->hdr.udp->uh_dport, + pd->ip_sum, &pd->hdr.udp->uh_sum, + &nk->addr[pd->didx], + nk->port[pd->didx], 1, af); + dport = pd->hdr.udp->uh_dport; + pd->dport = &pd->hdr.udp->uh_dport; + } + rewrite++; + break; +#ifdef INET + case IPPROTO_ICMP: + nk->port[0] = nk->port[1]; + if (PF_ANEQ(saddr, &nk->addr[pd->sidx], AF_INET)) + pf_change_a(&saddr->v4.s_addr, pd->ip_sum, + nk->addr[pd->sidx].v4.s_addr, 0); + + if (PF_ANEQ(daddr, &nk->addr[pd->didx], AF_INET)) + pf_change_a(&daddr->v4.s_addr, pd->ip_sum, + nk->addr[pd->didx].v4.s_addr, 0); + + if (nk->port[1] != pd->hdr.icmp->icmp_id) { + pd->hdr.icmp->icmp_cksum = pf_cksum_fixup( + pd->hdr.icmp->icmp_cksum, sport, + nk->port[1], 0); + pd->hdr.icmp->icmp_id = nk->port[1]; + pd->sport = &pd->hdr.icmp->icmp_id; + } + m_copyback(m, off, ICMP_MINLEN, (caddr_t)pd->hdr.icmp); + break; +#endif /* INET */ +#ifdef INET6 + case IPPROTO_ICMPV6: + nk->port[0] = nk->port[1]; + if (PF_ANEQ(saddr, &nk->addr[pd->sidx], AF_INET6)) + pf_change_a6(saddr, &pd->hdr.icmp6->icmp6_cksum, + &nk->addr[pd->sidx], 0); + + if (PF_ANEQ(daddr, &nk->addr[pd->didx], AF_INET6)) + pf_change_a6(daddr, &pd->hdr.icmp6->icmp6_cksum, + &nk->addr[pd->didx], 0); + rewrite++; + break; +#endif /* INET */ + default: + switch (af) { +#ifdef INET + case AF_INET: + if (PF_ANEQ(saddr, + &nk->addr[pd->sidx], AF_INET)) + pf_change_a(&saddr->v4.s_addr, + pd->ip_sum, + nk->addr[pd->sidx].v4.s_addr, 0); + + if (PF_ANEQ(daddr, + &nk->addr[pd->didx], AF_INET)) + pf_change_a(&daddr->v4.s_addr, + pd->ip_sum, + nk->addr[pd->didx].v4.s_addr, 0); + break; +#endif /* INET */ +#ifdef INET6 + case AF_INET6: + if (PF_ANEQ(saddr, + &nk->addr[pd->sidx], AF_INET6)) + PF_ACPY(saddr, &nk->addr[pd->sidx], af); + + if (PF_ANEQ(daddr, + &nk->addr[pd->didx], AF_INET6)) + PF_ACPY(saddr, &nk->addr[pd->didx], af); + break; +#endif /* INET */ + } + break; + } + if (nr->natpass) + r = NULL; + pd->nat_rule = nr; + } + + while (r != NULL) { + r->evaluations++; + if (pfi_kif_match(r->kif, kif) == r->ifnot) + r = r->skip[PF_SKIP_IFP].ptr; + else if (r->direction && r->direction != direction) + r = r->skip[PF_SKIP_DIR].ptr; + else if (r->af && r->af != af) + r = r->skip[PF_SKIP_AF].ptr; + else if (r->proto && r->proto != pd->proto) + r = r->skip[PF_SKIP_PROTO].ptr; + else if (PF_MISMATCHAW(&r->src.addr, saddr, af, + r->src.neg, kif, M_GETFIB(m))) + r = r->skip[PF_SKIP_SRC_ADDR].ptr; + /* tcp/udp only. port_op always 0 in other cases */ + else if (r->src.port_op && !pf_match_port(r->src.port_op, + r->src.port[0], r->src.port[1], sport)) + r = r->skip[PF_SKIP_SRC_PORT].ptr; + else if (PF_MISMATCHAW(&r->dst.addr, daddr, af, + r->dst.neg, NULL, M_GETFIB(m))) + r = r->skip[PF_SKIP_DST_ADDR].ptr; + /* tcp/udp only. port_op always 0 in other cases */ + else if (r->dst.port_op && !pf_match_port(r->dst.port_op, + r->dst.port[0], r->dst.port[1], dport)) + r = r->skip[PF_SKIP_DST_PORT].ptr; + /* icmp only. type always 0 in other cases */ + else if (r->type && r->type != icmptype + 1) + r = TAILQ_NEXT(r, entries); + /* icmp only. type always 0 in other cases */ + else if (r->code && r->code != icmpcode + 1) + r = TAILQ_NEXT(r, entries); + else if (r->tos && !(r->tos == pd->tos)) + r = TAILQ_NEXT(r, entries); + else if (r->rule_flag & PFRULE_FRAGMENT) + r = TAILQ_NEXT(r, entries); + else if (pd->proto == IPPROTO_TCP && + (r->flagset & th->th_flags) != r->flags) + r = TAILQ_NEXT(r, entries); + /* tcp/udp only. uid.op always 0 in other cases */ + else if (r->uid.op && (pd->lookup.done || (pd->lookup.done = + pf_socket_lookup(direction, pd, m), 1)) && + !pf_match_uid(r->uid.op, r->uid.uid[0], r->uid.uid[1], + pd->lookup.uid)) + r = TAILQ_NEXT(r, entries); + /* tcp/udp only. gid.op always 0 in other cases */ + else if (r->gid.op && (pd->lookup.done || (pd->lookup.done = + pf_socket_lookup(direction, pd, m), 1)) && + !pf_match_gid(r->gid.op, r->gid.gid[0], r->gid.gid[1], + pd->lookup.gid)) + r = TAILQ_NEXT(r, entries); + else if (r->prob && + r->prob <= arc4random()) + r = TAILQ_NEXT(r, entries); + else if (r->match_tag && !pf_match_tag(m, r, &tag, + pd->pf_mtag ? pd->pf_mtag->tag : 0)) + r = TAILQ_NEXT(r, entries); + else if (r->os_fingerprint != PF_OSFP_ANY && + (pd->proto != IPPROTO_TCP || !pf_osfp_match( + pf_osfp_fingerprint(pd, m, off, th), + r->os_fingerprint))) + r = TAILQ_NEXT(r, entries); + else { + if (r->tag) + tag = r->tag; + if (r->rtableid >= 0) + rtableid = r->rtableid; + if (r->anchor == NULL) { + match = 1; + *rm = r; + *am = a; + *rsm = ruleset; + if ((*rm)->quick) + break; + r = TAILQ_NEXT(r, entries); + } else + pf_step_into_anchor(&asd, &ruleset, + PF_RULESET_FILTER, &r, &a, &match); + } + if (r == NULL && pf_step_out_of_anchor(&asd, &ruleset, + PF_RULESET_FILTER, &r, &a, &match)) + break; + } + r = *rm; + a = *am; + ruleset = *rsm; + + REASON_SET(&reason, PFRES_MATCH); + + if (r->log || (nr != NULL && nr->log)) { + if (rewrite) + m_copyback(m, off, hdrlen, pd->hdr.any); + PFLOG_PACKET(kif, m, af, direction, reason, r->log ? r : nr, a, + ruleset, pd, 1); + } + + if ((r->action == PF_DROP) && + ((r->rule_flag & PFRULE_RETURNRST) || + (r->rule_flag & PFRULE_RETURNICMP) || + (r->rule_flag & PFRULE_RETURN))) { + /* undo NAT changes, if they have taken place */ + if (nr != NULL) { + PF_ACPY(saddr, &sk->addr[pd->sidx], af); + PF_ACPY(daddr, &sk->addr[pd->didx], af); + if (pd->sport) + *pd->sport = sk->port[pd->sidx]; + if (pd->dport) + *pd->dport = sk->port[pd->didx]; + if (pd->proto_sum) + *pd->proto_sum = bproto_sum; + if (pd->ip_sum) + *pd->ip_sum = bip_sum; + m_copyback(m, off, hdrlen, pd->hdr.any); + } + if (pd->proto == IPPROTO_TCP && + ((r->rule_flag & PFRULE_RETURNRST) || + (r->rule_flag & PFRULE_RETURN)) && + !(th->th_flags & TH_RST)) { + u_int32_t ack = ntohl(th->th_seq) + pd->p_len; + int len = 0; +#ifdef INET + struct ip *h4; +#endif +#ifdef INET6 + struct ip6_hdr *h6; +#endif + + switch (af) { +#ifdef INET + case AF_INET: + h4 = mtod(m, struct ip *); + len = ntohs(h4->ip_len) - off; + break; +#endif +#ifdef INET6 + case AF_INET6: + h6 = mtod(m, struct ip6_hdr *); + len = ntohs(h6->ip6_plen) - (off - sizeof(*h6)); + break; +#endif + } + + if (pf_check_proto_cksum(m, off, len, IPPROTO_TCP, af)) + REASON_SET(&reason, PFRES_PROTCKSUM); + else { + if (th->th_flags & TH_SYN) + ack++; + if (th->th_flags & TH_FIN) + ack++; + pf_send_tcp(m, r, af, pd->dst, + pd->src, th->th_dport, th->th_sport, + ntohl(th->th_ack), ack, TH_RST|TH_ACK, 0, 0, + r->return_ttl, 1, 0, kif->pfik_ifp); + } + } else if (pd->proto != IPPROTO_ICMP && af == AF_INET && + r->return_icmp) + pf_send_icmp(m, r->return_icmp >> 8, + r->return_icmp & 255, af, r); + else if (pd->proto != IPPROTO_ICMPV6 && af == AF_INET6 && + r->return_icmp6) + pf_send_icmp(m, r->return_icmp6 >> 8, + r->return_icmp6 & 255, af, r); + } + + if (r->action == PF_DROP) + goto cleanup; + + if (tag > 0 && pf_tag_packet(m, pd, tag)) { + REASON_SET(&reason, PFRES_MEMORY); + goto cleanup; + } + if (rtableid >= 0) + M_SETFIB(m, rtableid); + + if (!state_icmp && (r->keep_state || nr != NULL || + (pd->flags & PFDESC_TCP_NORM))) { + int action; + action = pf_create_state(r, nr, a, pd, nsn, nk, sk, m, off, + sport, dport, &rewrite, kif, sm, tag, bproto_sum, bip_sum, + hdrlen); + if (action != PF_PASS) + return (action); + } else { + if (sk != NULL) + uma_zfree(V_pf_state_key_z, sk); + if (nk != NULL) + uma_zfree(V_pf_state_key_z, nk); + } + + /* copy back packet headers if we performed NAT operations */ + if (rewrite) + m_copyback(m, off, hdrlen, pd->hdr.any); + + if (*sm != NULL && !((*sm)->state_flags & PFSTATE_NOSYNC) && + direction == PF_OUT && + pfsync_defer_ptr != NULL && pfsync_defer_ptr(*sm, m)) + /* + * We want the state created, but we dont + * want to send this in case a partner + * firewall has to know about it to allow + * replies through it. + */ + return (PF_DEFER); + + return (PF_PASS); + +cleanup: + if (sk != NULL) + uma_zfree(V_pf_state_key_z, sk); + if (nk != NULL) + uma_zfree(V_pf_state_key_z, nk); + return (PF_DROP); +} + +static int +pf_create_state(struct pf_rule *r, struct pf_rule *nr, struct pf_rule *a, + struct pf_pdesc *pd, struct pf_src_node *nsn, struct pf_state_key *nk, + struct pf_state_key *sk, struct mbuf *m, int off, u_int16_t sport, + u_int16_t dport, int *rewrite, struct pfi_kif *kif, struct pf_state **sm, + int tag, u_int16_t bproto_sum, u_int16_t bip_sum, int hdrlen) +{ + struct pf_state *s = NULL; + struct pf_src_node *sn = NULL; + struct tcphdr *th = pd->hdr.tcp; + u_int16_t mss = V_tcp_mssdflt; + u_short reason; + + /* check maximums */ + if (r->max_states && (r->states_cur >= r->max_states)) { + V_pf_status.lcounters[LCNT_STATES]++; + REASON_SET(&reason, PFRES_MAXSTATES); + return (PF_DROP); + } + /* src node for filter rule */ + if ((r->rule_flag & PFRULE_SRCTRACK || + r->rpool.opts & PF_POOL_STICKYADDR) && + pf_insert_src_node(&sn, r, pd->src, pd->af) != 0) { + REASON_SET(&reason, PFRES_SRCLIMIT); + goto csfailed; + } + /* src node for translation rule */ + if (nr != NULL && (nr->rpool.opts & PF_POOL_STICKYADDR) && + pf_insert_src_node(&nsn, nr, &sk->addr[pd->sidx], pd->af)) { + REASON_SET(&reason, PFRES_SRCLIMIT); + goto csfailed; + } + s = uma_zalloc(V_pf_state_z, M_NOWAIT | M_ZERO); + if (s == NULL) { + REASON_SET(&reason, PFRES_MEMORY); + goto csfailed; + } + s->rule.ptr = r; + s->nat_rule.ptr = nr; + s->anchor.ptr = a; + STATE_INC_COUNTERS(s); + if (r->allow_opts) + s->state_flags |= PFSTATE_ALLOWOPTS; + if (r->rule_flag & PFRULE_STATESLOPPY) + s->state_flags |= PFSTATE_SLOPPY; + s->log = r->log & PF_LOG_ALL; + s->sync_state = PFSYNC_S_NONE; + if (nr != NULL) + s->log |= nr->log & PF_LOG_ALL; + switch (pd->proto) { + case IPPROTO_TCP: + s->src.seqlo = ntohl(th->th_seq); + s->src.seqhi = s->src.seqlo + pd->p_len + 1; + if ((th->th_flags & (TH_SYN|TH_ACK)) == TH_SYN && + r->keep_state == PF_STATE_MODULATE) { + /* Generate sequence number modulator */ + if ((s->src.seqdiff = pf_tcp_iss(pd) - s->src.seqlo) == + 0) + s->src.seqdiff = 1; + pf_change_a(&th->th_seq, &th->th_sum, + htonl(s->src.seqlo + s->src.seqdiff), 0); + *rewrite = 1; + } else + s->src.seqdiff = 0; + if (th->th_flags & TH_SYN) { + s->src.seqhi++; + s->src.wscale = pf_get_wscale(m, off, + th->th_off, pd->af); + } + s->src.max_win = MAX(ntohs(th->th_win), 1); + if (s->src.wscale & PF_WSCALE_MASK) { + /* Remove scale factor from initial window */ + int win = s->src.max_win; + win += 1 << (s->src.wscale & PF_WSCALE_MASK); + s->src.max_win = (win - 1) >> + (s->src.wscale & PF_WSCALE_MASK); + } + if (th->th_flags & TH_FIN) + s->src.seqhi++; + s->dst.seqhi = 1; + s->dst.max_win = 1; + s->src.state = TCPS_SYN_SENT; + s->dst.state = TCPS_CLOSED; + s->timeout = PFTM_TCP_FIRST_PACKET; + break; + case IPPROTO_UDP: + s->src.state = PFUDPS_SINGLE; + s->dst.state = PFUDPS_NO_TRAFFIC; + s->timeout = PFTM_UDP_FIRST_PACKET; + break; + case IPPROTO_ICMP: +#ifdef INET6 + case IPPROTO_ICMPV6: +#endif + s->timeout = PFTM_ICMP_FIRST_PACKET; + break; + default: + s->src.state = PFOTHERS_SINGLE; + s->dst.state = PFOTHERS_NO_TRAFFIC; + s->timeout = PFTM_OTHER_FIRST_PACKET; + } + + s->creation = time_uptime; + s->expire = time_uptime; + + if (sn != NULL) { + s->src_node = sn; + s->src_node->states++; + } + if (nsn != NULL) { + /* XXX We only modify one side for now. */ + PF_ACPY(&nsn->raddr, &nk->addr[1], pd->af); + s->nat_src_node = nsn; + s->nat_src_node->states++; + } + if (pd->proto == IPPROTO_TCP) { + if ((pd->flags & PFDESC_TCP_NORM) && pf_normalize_tcp_init(m, + off, pd, th, &s->src, &s->dst)) { + REASON_SET(&reason, PFRES_MEMORY); + pf_src_tree_remove_state(s); + STATE_DEC_COUNTERS(s); + uma_zfree(V_pf_state_z, s); + return (PF_DROP); + } + if ((pd->flags & PFDESC_TCP_NORM) && s->src.scrub && + pf_normalize_tcp_stateful(m, off, pd, &reason, th, s, + &s->src, &s->dst, rewrite)) { + /* This really shouldn't happen!!! */ + DPFPRINTF(PF_DEBUG_URGENT, + ("pf_normalize_tcp_stateful failed on first pkt")); + pf_normalize_tcp_cleanup(s); + pf_src_tree_remove_state(s); + STATE_DEC_COUNTERS(s); + uma_zfree(V_pf_state_z, s); + return (PF_DROP); + } + } + s->direction = pd->dir; + + /* + * sk/nk could already been setup by pf_get_translation(). + */ + if (nr == NULL) { + KASSERT((sk == NULL && nk == NULL), ("%s: nr %p sk %p, nk %p", + __func__, nr, sk, nk)); + sk = pf_state_key_setup(pd, pd->src, pd->dst, sport, dport); + if (sk == NULL) + goto csfailed; + nk = sk; + } else + KASSERT((sk != NULL && nk != NULL), ("%s: nr %p sk %p, nk %p", + __func__, nr, sk, nk)); + + /* Swap sk/nk for PF_OUT. */ + if (pf_state_insert(BOUND_IFACE(r, kif), + (pd->dir == PF_IN) ? sk : nk, + (pd->dir == PF_IN) ? nk : sk, s)) { + if (pd->proto == IPPROTO_TCP) + pf_normalize_tcp_cleanup(s); + REASON_SET(&reason, PFRES_STATEINS); + pf_src_tree_remove_state(s); + STATE_DEC_COUNTERS(s); + uma_zfree(V_pf_state_z, s); + return (PF_DROP); + } else + *sm = s; + + pf_set_rt_ifp(s, pd->src); /* needs s->state_key set */ + if (tag > 0) + s->tag = tag; + if (pd->proto == IPPROTO_TCP && (th->th_flags & (TH_SYN|TH_ACK)) == + TH_SYN && r->keep_state == PF_STATE_SYNPROXY) { + s->src.state = PF_TCPS_PROXY_SRC; + /* undo NAT changes, if they have taken place */ + if (nr != NULL) { + struct pf_state_key *skt = s->key[PF_SK_WIRE]; + if (pd->dir == PF_OUT) + skt = s->key[PF_SK_STACK]; + PF_ACPY(pd->src, &skt->addr[pd->sidx], pd->af); + PF_ACPY(pd->dst, &skt->addr[pd->didx], pd->af); + if (pd->sport) + *pd->sport = skt->port[pd->sidx]; + if (pd->dport) + *pd->dport = skt->port[pd->didx]; + if (pd->proto_sum) + *pd->proto_sum = bproto_sum; + if (pd->ip_sum) + *pd->ip_sum = bip_sum; + m_copyback(m, off, hdrlen, pd->hdr.any); + } + s->src.seqhi = htonl(arc4random()); + /* Find mss option */ + int rtid = M_GETFIB(m); + mss = pf_get_mss(m, off, th->th_off, pd->af); + mss = pf_calc_mss(pd->src, pd->af, rtid, mss); + mss = pf_calc_mss(pd->dst, pd->af, rtid, mss); + s->src.mss = mss; + pf_send_tcp(NULL, r, pd->af, pd->dst, pd->src, th->th_dport, + th->th_sport, s->src.seqhi, ntohl(th->th_seq) + 1, + TH_SYN|TH_ACK, 0, s->src.mss, 0, 1, 0, NULL); + REASON_SET(&reason, PFRES_SYNPROXY); + return (PF_SYNPROXY_DROP); + } + + return (PF_PASS); + +csfailed: + if (sk != NULL) + uma_zfree(V_pf_state_key_z, sk); + if (nk != NULL) + uma_zfree(V_pf_state_key_z, nk); + + if (sn != NULL && sn->states == 0 && sn->expire == 0) { + pf_remove_src_node(sn); + V_pf_status.scounters[SCNT_SRC_NODE_REMOVALS]++; + V_pf_status.src_nodes--; + uma_zfree(V_pf_sources_z, sn); + } + if (nsn != sn && nsn != NULL && nsn->states == 0 && nsn->expire == 0) { + pf_remove_src_node(nsn); + V_pf_status.scounters[SCNT_SRC_NODE_REMOVALS]++; + V_pf_status.src_nodes--; + uma_zfree(V_pf_sources_z, nsn); + } + return (PF_DROP); +} + +static int +pf_test_fragment(struct pf_rule **rm, int direction, struct pfi_kif *kif, + struct mbuf *m, void *h, struct pf_pdesc *pd, struct pf_rule **am, + struct pf_ruleset **rsm) +{ + struct pf_rule *r, *a = NULL; + struct pf_ruleset *ruleset = NULL; + sa_family_t af = pd->af; + u_short reason; + int tag = -1; + int asd = 0; + int match = 0; + + PF_RULES_RASSERT(); + + r = TAILQ_FIRST(pf_main_ruleset.rules[PF_RULESET_FILTER].active.ptr); + while (r != NULL) { + r->evaluations++; + if (pfi_kif_match(r->kif, kif) == r->ifnot) + r = r->skip[PF_SKIP_IFP].ptr; + else if (r->direction && r->direction != direction) + r = r->skip[PF_SKIP_DIR].ptr; + else if (r->af && r->af != af) + r = r->skip[PF_SKIP_AF].ptr; + else if (r->proto && r->proto != pd->proto) + r = r->skip[PF_SKIP_PROTO].ptr; + else if (PF_MISMATCHAW(&r->src.addr, pd->src, af, + r->src.neg, kif, M_GETFIB(m))) + r = r->skip[PF_SKIP_SRC_ADDR].ptr; + else if (PF_MISMATCHAW(&r->dst.addr, pd->dst, af, + r->dst.neg, NULL, M_GETFIB(m))) + r = r->skip[PF_SKIP_DST_ADDR].ptr; + else if (r->tos && !(r->tos == pd->tos)) + r = TAILQ_NEXT(r, entries); + else if (r->os_fingerprint != PF_OSFP_ANY) + r = TAILQ_NEXT(r, entries); + else if (pd->proto == IPPROTO_UDP && + (r->src.port_op || r->dst.port_op)) + r = TAILQ_NEXT(r, entries); + else if (pd->proto == IPPROTO_TCP && + (r->src.port_op || r->dst.port_op || r->flagset)) + r = TAILQ_NEXT(r, entries); + else if ((pd->proto == IPPROTO_ICMP || + pd->proto == IPPROTO_ICMPV6) && + (r->type || r->code)) + r = TAILQ_NEXT(r, entries); + else if (r->prob && r->prob <= + (arc4random() % (UINT_MAX - 1) + 1)) + r = TAILQ_NEXT(r, entries); + else if (r->match_tag && !pf_match_tag(m, r, &tag, + pd->pf_mtag ? pd->pf_mtag->tag : 0)) + r = TAILQ_NEXT(r, entries); + else { + if (r->anchor == NULL) { + match = 1; + *rm = r; + *am = a; + *rsm = ruleset; + if ((*rm)->quick) + break; + r = TAILQ_NEXT(r, entries); + } else + pf_step_into_anchor(&asd, &ruleset, + PF_RULESET_FILTER, &r, &a, &match); + } + if (r == NULL && pf_step_out_of_anchor(&asd, &ruleset, + PF_RULESET_FILTER, &r, &a, &match)) + break; + } + r = *rm; + a = *am; + ruleset = *rsm; + + REASON_SET(&reason, PFRES_MATCH); + + if (r->log) + PFLOG_PACKET(kif, m, af, direction, reason, r, a, ruleset, pd, + 1); + + if (r->action != PF_PASS) + return (PF_DROP); + + if (tag > 0 && pf_tag_packet(m, pd, tag)) { + REASON_SET(&reason, PFRES_MEMORY); + return (PF_DROP); + } + + return (PF_PASS); +} + +static int +pf_tcp_track_full(struct pf_state_peer *src, struct pf_state_peer *dst, + struct pf_state **state, struct pfi_kif *kif, struct mbuf *m, int off, + struct pf_pdesc *pd, u_short *reason, int *copyback) +{ + struct tcphdr *th = pd->hdr.tcp; + u_int16_t win = ntohs(th->th_win); + u_int32_t ack, end, seq, orig_seq; + u_int8_t sws, dws; + int ackskew; + + if (src->wscale && dst->wscale && !(th->th_flags & TH_SYN)) { + sws = src->wscale & PF_WSCALE_MASK; + dws = dst->wscale & PF_WSCALE_MASK; + } else + sws = dws = 0; + + /* + * Sequence tracking algorithm from Guido van Rooij's paper: + * http://www.madison-gurkha.com/publications/tcp_filtering/ + * tcp_filtering.ps + */ + + orig_seq = seq = ntohl(th->th_seq); + if (src->seqlo == 0) { + /* First packet from this end. Set its state */ + + if ((pd->flags & PFDESC_TCP_NORM || dst->scrub) && + src->scrub == NULL) { + if (pf_normalize_tcp_init(m, off, pd, th, src, dst)) { + REASON_SET(reason, PFRES_MEMORY); + return (PF_DROP); + } + } + + /* Deferred generation of sequence number modulator */ + if (dst->seqdiff && !src->seqdiff) { + /* use random iss for the TCP server */ + while ((src->seqdiff = arc4random() - seq) == 0) + ; + ack = ntohl(th->th_ack) - dst->seqdiff; + pf_change_a(&th->th_seq, &th->th_sum, htonl(seq + + src->seqdiff), 0); + pf_change_a(&th->th_ack, &th->th_sum, htonl(ack), 0); + *copyback = 1; + } else { + ack = ntohl(th->th_ack); + } + + end = seq + pd->p_len; + if (th->th_flags & TH_SYN) { + end++; + if (dst->wscale & PF_WSCALE_FLAG) { + src->wscale = pf_get_wscale(m, off, th->th_off, + pd->af); + if (src->wscale & PF_WSCALE_FLAG) { + /* Remove scale factor from initial + * window */ + sws = src->wscale & PF_WSCALE_MASK; + win = ((u_int32_t)win + (1 << sws) - 1) + >> sws; + dws = dst->wscale & PF_WSCALE_MASK; + } else { + /* fixup other window */ + dst->max_win <<= dst->wscale & + PF_WSCALE_MASK; + /* in case of a retrans SYN|ACK */ + dst->wscale = 0; + } + } + } + if (th->th_flags & TH_FIN) + end++; + + src->seqlo = seq; + if (src->state < TCPS_SYN_SENT) + src->state = TCPS_SYN_SENT; + + /* + * May need to slide the window (seqhi may have been set by + * the crappy stack check or if we picked up the connection + * after establishment) + */ + if (src->seqhi == 1 || + SEQ_GEQ(end + MAX(1, dst->max_win << dws), src->seqhi)) + src->seqhi = end + MAX(1, dst->max_win << dws); + if (win > src->max_win) + src->max_win = win; + + } else { + ack = ntohl(th->th_ack) - dst->seqdiff; + if (src->seqdiff) { + /* Modulate sequence numbers */ + pf_change_a(&th->th_seq, &th->th_sum, htonl(seq + + src->seqdiff), 0); + pf_change_a(&th->th_ack, &th->th_sum, htonl(ack), 0); + *copyback = 1; + } + end = seq + pd->p_len; + if (th->th_flags & TH_SYN) + end++; + if (th->th_flags & TH_FIN) + end++; + } + + if ((th->th_flags & TH_ACK) == 0) { + /* Let it pass through the ack skew check */ + ack = dst->seqlo; + } else if ((ack == 0 && + (th->th_flags & (TH_ACK|TH_RST)) == (TH_ACK|TH_RST)) || + /* broken tcp stacks do not set ack */ + (dst->state < TCPS_SYN_SENT)) { + /* + * Many stacks (ours included) will set the ACK number in an + * FIN|ACK if the SYN times out -- no sequence to ACK. + */ + ack = dst->seqlo; + } + + if (seq == end) { + /* Ease sequencing restrictions on no data packets */ + seq = src->seqlo; + end = seq; + } + + ackskew = dst->seqlo - ack; + + + /* + * Need to demodulate the sequence numbers in any TCP SACK options + * (Selective ACK). We could optionally validate the SACK values + * against the current ACK window, either forwards or backwards, but + * I'm not confident that SACK has been implemented properly + * everywhere. It wouldn't surprise me if several stacks accidently + * SACK too far backwards of previously ACKed data. There really aren't + * any security implications of bad SACKing unless the target stack + * doesn't validate the option length correctly. Someone trying to + * spoof into a TCP connection won't bother blindly sending SACK + * options anyway. + */ + if (dst->seqdiff && (th->th_off << 2) > sizeof(struct tcphdr)) { + if (pf_modulate_sack(m, off, pd, th, dst)) + *copyback = 1; + } + + +#define MAXACKWINDOW (0xffff + 1500) /* 1500 is an arbitrary fudge factor */ + if (SEQ_GEQ(src->seqhi, end) && + /* Last octet inside other's window space */ + SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)) && + /* Retrans: not more than one window back */ + (ackskew >= -MAXACKWINDOW) && + /* Acking not more than one reassembled fragment backwards */ + (ackskew <= (MAXACKWINDOW << sws)) && + /* Acking not more than one window forward */ + ((th->th_flags & TH_RST) == 0 || orig_seq == src->seqlo || + (orig_seq == src->seqlo + 1) || (orig_seq + 1 == src->seqlo) || + (pd->flags & PFDESC_IP_REAS) == 0)) { + /* Require an exact/+1 sequence match on resets when possible */ + + if (dst->scrub || src->scrub) { + if (pf_normalize_tcp_stateful(m, off, pd, reason, th, + *state, src, dst, copyback)) + return (PF_DROP); + } + + /* update max window */ + if (src->max_win < win) + src->max_win = win; + /* synchronize sequencing */ + if (SEQ_GT(end, src->seqlo)) + src->seqlo = end; + /* slide the window of what the other end can send */ + if (SEQ_GEQ(ack + (win << sws), dst->seqhi)) + dst->seqhi = ack + MAX((win << sws), 1); + + + /* update states */ + if (th->th_flags & TH_SYN) + if (src->state < TCPS_SYN_SENT) + src->state = TCPS_SYN_SENT; + if (th->th_flags & TH_FIN) + if (src->state < TCPS_CLOSING) + src->state = TCPS_CLOSING; + if (th->th_flags & TH_ACK) { + if (dst->state == TCPS_SYN_SENT) { + dst->state = TCPS_ESTABLISHED; + if (src->state == TCPS_ESTABLISHED && + (*state)->src_node != NULL && + pf_src_connlimit(state)) { + REASON_SET(reason, PFRES_SRCLIMIT); + return (PF_DROP); + } + } else if (dst->state == TCPS_CLOSING) + dst->state = TCPS_FIN_WAIT_2; + } + if (th->th_flags & TH_RST) + src->state = dst->state = TCPS_TIME_WAIT; + + /* update expire time */ + (*state)->expire = time_uptime; + if (src->state >= TCPS_FIN_WAIT_2 && + dst->state >= TCPS_FIN_WAIT_2) + (*state)->timeout = PFTM_TCP_CLOSED; + else if (src->state >= TCPS_CLOSING && + dst->state >= TCPS_CLOSING) + (*state)->timeout = PFTM_TCP_FIN_WAIT; + else if (src->state < TCPS_ESTABLISHED || + dst->state < TCPS_ESTABLISHED) + (*state)->timeout = PFTM_TCP_OPENING; + else if (src->state >= TCPS_CLOSING || + dst->state >= TCPS_CLOSING) + (*state)->timeout = PFTM_TCP_CLOSING; + else + (*state)->timeout = PFTM_TCP_ESTABLISHED; + + /* Fall through to PASS packet */ + + } else if ((dst->state < TCPS_SYN_SENT || + dst->state >= TCPS_FIN_WAIT_2 || + src->state >= TCPS_FIN_WAIT_2) && + SEQ_GEQ(src->seqhi + MAXACKWINDOW, end) && + /* Within a window forward of the originating packet */ + SEQ_GEQ(seq, src->seqlo - MAXACKWINDOW)) { + /* Within a window backward of the originating packet */ + + /* + * This currently handles three situations: + * 1) Stupid stacks will shotgun SYNs before their peer + * replies. + * 2) When PF catches an already established stream (the + * firewall rebooted, the state table was flushed, routes + * changed...) + * 3) Packets get funky immediately after the connection + * closes (this should catch Solaris spurious ACK|FINs + * that web servers like to spew after a close) + * + * This must be a little more careful than the above code + * since packet floods will also be caught here. We don't + * update the TTL here to mitigate the damage of a packet + * flood and so the same code can handle awkward establishment + * and a loosened connection close. + * In the establishment case, a correct peer response will + * validate the connection, go through the normal state code + * and keep updating the state TTL. + */ + + if (V_pf_status.debug >= PF_DEBUG_MISC) { + printf("pf: loose state match: "); + pf_print_state(*state); + pf_print_flags(th->th_flags); + printf(" seq=%u (%u) ack=%u len=%u ackskew=%d " + "pkts=%llu:%llu dir=%s,%s\n", seq, orig_seq, ack, + pd->p_len, ackskew, (unsigned long long)(*state)->packets[0], + (unsigned long long)(*state)->packets[1], + pd->dir == PF_IN ? "in" : "out", + pd->dir == (*state)->direction ? "fwd" : "rev"); + } + + if (dst->scrub || src->scrub) { + if (pf_normalize_tcp_stateful(m, off, pd, reason, th, + *state, src, dst, copyback)) + return (PF_DROP); + } + + /* update max window */ + if (src->max_win < win) + src->max_win = win; + /* synchronize sequencing */ + if (SEQ_GT(end, src->seqlo)) + src->seqlo = end; + /* slide the window of what the other end can send */ + if (SEQ_GEQ(ack + (win << sws), dst->seqhi)) + dst->seqhi = ack + MAX((win << sws), 1); + + /* + * Cannot set dst->seqhi here since this could be a shotgunned + * SYN and not an already established connection. + */ + + if (th->th_flags & TH_FIN) + if (src->state < TCPS_CLOSING) + src->state = TCPS_CLOSING; + if (th->th_flags & TH_RST) + src->state = dst->state = TCPS_TIME_WAIT; + + /* Fall through to PASS packet */ + + } else { + if ((*state)->dst.state == TCPS_SYN_SENT && + (*state)->src.state == TCPS_SYN_SENT) { + /* Send RST for state mismatches during handshake */ + if (!(th->th_flags & TH_RST)) + pf_send_tcp(NULL, (*state)->rule.ptr, pd->af, + pd->dst, pd->src, th->th_dport, + th->th_sport, ntohl(th->th_ack), 0, + TH_RST, 0, 0, + (*state)->rule.ptr->return_ttl, 1, 0, + kif->pfik_ifp); + src->seqlo = 0; + src->seqhi = 1; + src->max_win = 1; + } else if (V_pf_status.debug >= PF_DEBUG_MISC) { + printf("pf: BAD state: "); + pf_print_state(*state); + pf_print_flags(th->th_flags); + printf(" seq=%u (%u) ack=%u len=%u ackskew=%d " + "pkts=%llu:%llu dir=%s,%s\n", + seq, orig_seq, ack, pd->p_len, ackskew, + (unsigned long long)(*state)->packets[0], + (unsigned long long)(*state)->packets[1], + pd->dir == PF_IN ? "in" : "out", + pd->dir == (*state)->direction ? "fwd" : "rev"); + printf("pf: State failure on: %c %c %c %c | %c %c\n", + SEQ_GEQ(src->seqhi, end) ? ' ' : '1', + SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)) ? + ' ': '2', + (ackskew >= -MAXACKWINDOW) ? ' ' : '3', + (ackskew <= (MAXACKWINDOW << sws)) ? ' ' : '4', + SEQ_GEQ(src->seqhi + MAXACKWINDOW, end) ?' ' :'5', + SEQ_GEQ(seq, src->seqlo - MAXACKWINDOW) ?' ' :'6'); + } + REASON_SET(reason, PFRES_BADSTATE); + return (PF_DROP); + } + + return (PF_PASS); +} + +static int +pf_tcp_track_sloppy(struct pf_state_peer *src, struct pf_state_peer *dst, + struct pf_state **state, struct pf_pdesc *pd, u_short *reason) +{ + struct tcphdr *th = pd->hdr.tcp; + + if (th->th_flags & TH_SYN) + if (src->state < TCPS_SYN_SENT) + src->state = TCPS_SYN_SENT; + if (th->th_flags & TH_FIN) + if (src->state < TCPS_CLOSING) + src->state = TCPS_CLOSING; + if (th->th_flags & TH_ACK) { + if (dst->state == TCPS_SYN_SENT) { + dst->state = TCPS_ESTABLISHED; + if (src->state == TCPS_ESTABLISHED && + (*state)->src_node != NULL && + pf_src_connlimit(state)) { + REASON_SET(reason, PFRES_SRCLIMIT); + return (PF_DROP); + } + } else if (dst->state == TCPS_CLOSING) { + dst->state = TCPS_FIN_WAIT_2; + } else if (src->state == TCPS_SYN_SENT && + dst->state < TCPS_SYN_SENT) { + /* + * Handle a special sloppy case where we only see one + * half of the connection. If there is a ACK after + * the initial SYN without ever seeing a packet from + * the destination, set the connection to established. + */ + dst->state = src->state = TCPS_ESTABLISHED; + if ((*state)->src_node != NULL && + pf_src_connlimit(state)) { + REASON_SET(reason, PFRES_SRCLIMIT); + return (PF_DROP); + } + } else if (src->state == TCPS_CLOSING && + dst->state == TCPS_ESTABLISHED && + dst->seqlo == 0) { + /* + * Handle the closing of half connections where we + * don't see the full bidirectional FIN/ACK+ACK + * handshake. + */ + dst->state = TCPS_CLOSING; + } + } + if (th->th_flags & TH_RST) + src->state = dst->state = TCPS_TIME_WAIT; + + /* update expire time */ + (*state)->expire = time_uptime; + if (src->state >= TCPS_FIN_WAIT_2 && + dst->state >= TCPS_FIN_WAIT_2) + (*state)->timeout = PFTM_TCP_CLOSED; + else if (src->state >= TCPS_CLOSING && + dst->state >= TCPS_CLOSING) + (*state)->timeout = PFTM_TCP_FIN_WAIT; + else if (src->state < TCPS_ESTABLISHED || + dst->state < TCPS_ESTABLISHED) + (*state)->timeout = PFTM_TCP_OPENING; + else if (src->state >= TCPS_CLOSING || + dst->state >= TCPS_CLOSING) + (*state)->timeout = PFTM_TCP_CLOSING; + else + (*state)->timeout = PFTM_TCP_ESTABLISHED; + + return (PF_PASS); +} + +static int +pf_test_state_tcp(struct pf_state **state, int direction, struct pfi_kif *kif, + struct mbuf *m, int off, void *h, struct pf_pdesc *pd, + u_short *reason) +{ + struct pf_state_key_cmp key; + struct tcphdr *th = pd->hdr.tcp; + int copyback = 0; + struct pf_state_peer *src, *dst; + struct pf_state_key *sk; + + bzero(&key, sizeof(key)); + key.af = pd->af; + key.proto = IPPROTO_TCP; + if (direction == PF_IN) { /* wire side, straight */ + PF_ACPY(&key.addr[0], pd->src, key.af); + PF_ACPY(&key.addr[1], pd->dst, key.af); + key.port[0] = th->th_sport; + key.port[1] = th->th_dport; + } else { /* stack side, reverse */ + PF_ACPY(&key.addr[1], pd->src, key.af); + PF_ACPY(&key.addr[0], pd->dst, key.af); + key.port[1] = th->th_sport; + key.port[0] = th->th_dport; + } + + STATE_LOOKUP(kif, &key, direction, *state, pd); + + if (direction == (*state)->direction) { + src = &(*state)->src; + dst = &(*state)->dst; + } else { + src = &(*state)->dst; + dst = &(*state)->src; + } + + sk = (*state)->key[pd->didx]; + + if ((*state)->src.state == PF_TCPS_PROXY_SRC) { + if (direction != (*state)->direction) { + REASON_SET(reason, PFRES_SYNPROXY); + return (PF_SYNPROXY_DROP); + } + if (th->th_flags & TH_SYN) { + if (ntohl(th->th_seq) != (*state)->src.seqlo) { + REASON_SET(reason, PFRES_SYNPROXY); + return (PF_DROP); + } + pf_send_tcp(NULL, (*state)->rule.ptr, pd->af, pd->dst, + pd->src, th->th_dport, th->th_sport, + (*state)->src.seqhi, ntohl(th->th_seq) + 1, + TH_SYN|TH_ACK, 0, (*state)->src.mss, 0, 1, 0, NULL); + REASON_SET(reason, PFRES_SYNPROXY); + return (PF_SYNPROXY_DROP); + } else if (!(th->th_flags & TH_ACK) || + (ntohl(th->th_ack) != (*state)->src.seqhi + 1) || + (ntohl(th->th_seq) != (*state)->src.seqlo + 1)) { + REASON_SET(reason, PFRES_SYNPROXY); + return (PF_DROP); + } else if ((*state)->src_node != NULL && + pf_src_connlimit(state)) { + REASON_SET(reason, PFRES_SRCLIMIT); + return (PF_DROP); + } else + (*state)->src.state = PF_TCPS_PROXY_DST; + } + if ((*state)->src.state == PF_TCPS_PROXY_DST) { + if (direction == (*state)->direction) { + if (((th->th_flags & (TH_SYN|TH_ACK)) != TH_ACK) || + (ntohl(th->th_ack) != (*state)->src.seqhi + 1) || + (ntohl(th->th_seq) != (*state)->src.seqlo + 1)) { + REASON_SET(reason, PFRES_SYNPROXY); + return (PF_DROP); + } + (*state)->src.max_win = MAX(ntohs(th->th_win), 1); + if ((*state)->dst.seqhi == 1) + (*state)->dst.seqhi = htonl(arc4random()); + pf_send_tcp(NULL, (*state)->rule.ptr, pd->af, + &sk->addr[pd->sidx], &sk->addr[pd->didx], + sk->port[pd->sidx], sk->port[pd->didx], + (*state)->dst.seqhi, 0, TH_SYN, 0, + (*state)->src.mss, 0, 0, (*state)->tag, NULL); + REASON_SET(reason, PFRES_SYNPROXY); + return (PF_SYNPROXY_DROP); + } else if (((th->th_flags & (TH_SYN|TH_ACK)) != + (TH_SYN|TH_ACK)) || + (ntohl(th->th_ack) != (*state)->dst.seqhi + 1)) { + REASON_SET(reason, PFRES_SYNPROXY); + return (PF_DROP); + } else { + (*state)->dst.max_win = MAX(ntohs(th->th_win), 1); + (*state)->dst.seqlo = ntohl(th->th_seq); + pf_send_tcp(NULL, (*state)->rule.ptr, pd->af, pd->dst, + pd->src, th->th_dport, th->th_sport, + ntohl(th->th_ack), ntohl(th->th_seq) + 1, + TH_ACK, (*state)->src.max_win, 0, 0, 0, + (*state)->tag, NULL); + pf_send_tcp(NULL, (*state)->rule.ptr, pd->af, + &sk->addr[pd->sidx], &sk->addr[pd->didx], + sk->port[pd->sidx], sk->port[pd->didx], + (*state)->src.seqhi + 1, (*state)->src.seqlo + 1, + TH_ACK, (*state)->dst.max_win, 0, 0, 1, 0, NULL); + (*state)->src.seqdiff = (*state)->dst.seqhi - + (*state)->src.seqlo; + (*state)->dst.seqdiff = (*state)->src.seqhi - + (*state)->dst.seqlo; + (*state)->src.seqhi = (*state)->src.seqlo + + (*state)->dst.max_win; + (*state)->dst.seqhi = (*state)->dst.seqlo + + (*state)->src.max_win; + (*state)->src.wscale = (*state)->dst.wscale = 0; + (*state)->src.state = (*state)->dst.state = + TCPS_ESTABLISHED; + REASON_SET(reason, PFRES_SYNPROXY); + return (PF_SYNPROXY_DROP); + } + } + + if (((th->th_flags & (TH_SYN|TH_ACK)) == TH_SYN) && + dst->state >= TCPS_FIN_WAIT_2 && + src->state >= TCPS_FIN_WAIT_2) { + if (V_pf_status.debug >= PF_DEBUG_MISC) { + printf("pf: state reuse "); + pf_print_state(*state); + pf_print_flags(th->th_flags); + printf("\n"); + } + /* XXX make sure it's the same direction ?? */ + (*state)->src.state = (*state)->dst.state = TCPS_CLOSED; + pf_unlink_state(*state, PF_ENTER_LOCKED); + *state = NULL; + return (PF_DROP); + } + + if ((*state)->state_flags & PFSTATE_SLOPPY) { + if (pf_tcp_track_sloppy(src, dst, state, pd, reason) == PF_DROP) + return (PF_DROP); + } else { + if (pf_tcp_track_full(src, dst, state, kif, m, off, pd, reason, + ©back) == PF_DROP) + return (PF_DROP); + } + + /* translate source/destination address, if necessary */ + if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) { + struct pf_state_key *nk = (*state)->key[pd->didx]; + + if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], pd->af) || + nk->port[pd->sidx] != th->th_sport) + pf_change_ap(pd->src, &th->th_sport, pd->ip_sum, + &th->th_sum, &nk->addr[pd->sidx], + nk->port[pd->sidx], 0, pd->af); + + if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], pd->af) || + nk->port[pd->didx] != th->th_dport) + pf_change_ap(pd->dst, &th->th_dport, pd->ip_sum, + &th->th_sum, &nk->addr[pd->didx], + nk->port[pd->didx], 0, pd->af); + copyback = 1; + } + + /* Copyback sequence modulation or stateful scrub changes if needed */ + if (copyback) + m_copyback(m, off, sizeof(*th), (caddr_t)th); + + return (PF_PASS); +} + +static int +pf_test_state_udp(struct pf_state **state, int direction, struct pfi_kif *kif, + struct mbuf *m, int off, void *h, struct pf_pdesc *pd) +{ + struct pf_state_peer *src, *dst; + struct pf_state_key_cmp key; + struct udphdr *uh = pd->hdr.udp; + + bzero(&key, sizeof(key)); + key.af = pd->af; + key.proto = IPPROTO_UDP; + if (direction == PF_IN) { /* wire side, straight */ + PF_ACPY(&key.addr[0], pd->src, key.af); + PF_ACPY(&key.addr[1], pd->dst, key.af); + key.port[0] = uh->uh_sport; + key.port[1] = uh->uh_dport; + } else { /* stack side, reverse */ + PF_ACPY(&key.addr[1], pd->src, key.af); + PF_ACPY(&key.addr[0], pd->dst, key.af); + key.port[1] = uh->uh_sport; + key.port[0] = uh->uh_dport; + } + + STATE_LOOKUP(kif, &key, direction, *state, pd); + + if (direction == (*state)->direction) { + src = &(*state)->src; + dst = &(*state)->dst; + } else { + src = &(*state)->dst; + dst = &(*state)->src; + } + + /* update states */ + if (src->state < PFUDPS_SINGLE) + src->state = PFUDPS_SINGLE; + if (dst->state == PFUDPS_SINGLE) + dst->state = PFUDPS_MULTIPLE; + + /* update expire time */ + (*state)->expire = time_uptime; + if (src->state == PFUDPS_MULTIPLE && dst->state == PFUDPS_MULTIPLE) + (*state)->timeout = PFTM_UDP_MULTIPLE; + else + (*state)->timeout = PFTM_UDP_SINGLE; + + /* translate source/destination address, if necessary */ + if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) { + struct pf_state_key *nk = (*state)->key[pd->didx]; + + if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], pd->af) || + nk->port[pd->sidx] != uh->uh_sport) + pf_change_ap(pd->src, &uh->uh_sport, pd->ip_sum, + &uh->uh_sum, &nk->addr[pd->sidx], + nk->port[pd->sidx], 1, pd->af); + + if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], pd->af) || + nk->port[pd->didx] != uh->uh_dport) + pf_change_ap(pd->dst, &uh->uh_dport, pd->ip_sum, + &uh->uh_sum, &nk->addr[pd->didx], + nk->port[pd->didx], 1, pd->af); + m_copyback(m, off, sizeof(*uh), (caddr_t)uh); + } + + return (PF_PASS); +} + +static int +pf_test_state_icmp(struct pf_state **state, int direction, struct pfi_kif *kif, + struct mbuf *m, int off, void *h, struct pf_pdesc *pd, u_short *reason) +{ + struct pf_addr *saddr = pd->src, *daddr = pd->dst; + u_int16_t icmpid = 0, *icmpsum; + u_int8_t icmptype; + int state_icmp = 0; + struct pf_state_key_cmp key; + + bzero(&key, sizeof(key)); + switch (pd->proto) { +#ifdef INET + case IPPROTO_ICMP: + icmptype = pd->hdr.icmp->icmp_type; + icmpid = pd->hdr.icmp->icmp_id; + icmpsum = &pd->hdr.icmp->icmp_cksum; + + if (icmptype == ICMP_UNREACH || + icmptype == ICMP_SOURCEQUENCH || + icmptype == ICMP_REDIRECT || + icmptype == ICMP_TIMXCEED || + icmptype == ICMP_PARAMPROB) + state_icmp++; + break; +#endif /* INET */ +#ifdef INET6 + case IPPROTO_ICMPV6: + icmptype = pd->hdr.icmp6->icmp6_type; + icmpid = pd->hdr.icmp6->icmp6_id; + icmpsum = &pd->hdr.icmp6->icmp6_cksum; + + if (icmptype == ICMP6_DST_UNREACH || + icmptype == ICMP6_PACKET_TOO_BIG || + icmptype == ICMP6_TIME_EXCEEDED || + icmptype == ICMP6_PARAM_PROB) + state_icmp++; + break; +#endif /* INET6 */ + } + + if (!state_icmp) { + + /* + * ICMP query/reply message not related to a TCP/UDP packet. + * Search for an ICMP state. + */ + key.af = pd->af; + key.proto = pd->proto; + key.port[0] = key.port[1] = icmpid; + if (direction == PF_IN) { /* wire side, straight */ + PF_ACPY(&key.addr[0], pd->src, key.af); + PF_ACPY(&key.addr[1], pd->dst, key.af); + } else { /* stack side, reverse */ + PF_ACPY(&key.addr[1], pd->src, key.af); + PF_ACPY(&key.addr[0], pd->dst, key.af); + } + + STATE_LOOKUP(kif, &key, direction, *state, pd); + + (*state)->expire = time_uptime; + (*state)->timeout = PFTM_ICMP_ERROR_REPLY; + + /* translate source/destination address, if necessary */ + if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) { + struct pf_state_key *nk = (*state)->key[pd->didx]; + + switch (pd->af) { +#ifdef INET + case AF_INET: + if (PF_ANEQ(pd->src, + &nk->addr[pd->sidx], AF_INET)) + pf_change_a(&saddr->v4.s_addr, + pd->ip_sum, + nk->addr[pd->sidx].v4.s_addr, 0); + + if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], + AF_INET)) + pf_change_a(&daddr->v4.s_addr, + pd->ip_sum, + nk->addr[pd->didx].v4.s_addr, 0); + + if (nk->port[0] != + pd->hdr.icmp->icmp_id) { + pd->hdr.icmp->icmp_cksum = + pf_cksum_fixup( + pd->hdr.icmp->icmp_cksum, icmpid, + nk->port[pd->sidx], 0); + pd->hdr.icmp->icmp_id = + nk->port[pd->sidx]; + } + + m_copyback(m, off, ICMP_MINLEN, + (caddr_t )pd->hdr.icmp); + break; +#endif /* INET */ +#ifdef INET6 + case AF_INET6: + if (PF_ANEQ(pd->src, + &nk->addr[pd->sidx], AF_INET6)) + pf_change_a6(saddr, + &pd->hdr.icmp6->icmp6_cksum, + &nk->addr[pd->sidx], 0); + + if (PF_ANEQ(pd->dst, + &nk->addr[pd->didx], AF_INET6)) + pf_change_a6(daddr, + &pd->hdr.icmp6->icmp6_cksum, + &nk->addr[pd->didx], 0); + + m_copyback(m, off, sizeof(struct icmp6_hdr), + (caddr_t )pd->hdr.icmp6); + break; +#endif /* INET6 */ + } + } + return (PF_PASS); + + } else { + /* + * ICMP error message in response to a TCP/UDP packet. + * Extract the inner TCP/UDP header and search for that state. + */ + + struct pf_pdesc pd2; + bzero(&pd2, sizeof pd2); +#ifdef INET + struct ip h2; +#endif /* INET */ +#ifdef INET6 + struct ip6_hdr h2_6; + int terminal = 0; +#endif /* INET6 */ + int ipoff2 = 0; + int off2 = 0; + + pd2.af = pd->af; + /* Payload packet is from the opposite direction. */ + pd2.sidx = (direction == PF_IN) ? 1 : 0; + pd2.didx = (direction == PF_IN) ? 0 : 1; + switch (pd->af) { +#ifdef INET + case AF_INET: + /* offset of h2 in mbuf chain */ + ipoff2 = off + ICMP_MINLEN; + + if (!pf_pull_hdr(m, ipoff2, &h2, sizeof(h2), + NULL, reason, pd2.af)) { + DPFPRINTF(PF_DEBUG_MISC, + ("pf: ICMP error message too short " + "(ip)\n")); + return (PF_DROP); + } + /* + * ICMP error messages don't refer to non-first + * fragments + */ + if (h2.ip_off & htons(IP_OFFMASK)) { + REASON_SET(reason, PFRES_FRAG); + return (PF_DROP); + } + + /* offset of protocol header that follows h2 */ + off2 = ipoff2 + (h2.ip_hl << 2); + + pd2.proto = h2.ip_p; + pd2.src = (struct pf_addr *)&h2.ip_src; + pd2.dst = (struct pf_addr *)&h2.ip_dst; + pd2.ip_sum = &h2.ip_sum; + break; +#endif /* INET */ +#ifdef INET6 + case AF_INET6: + ipoff2 = off + sizeof(struct icmp6_hdr); + + if (!pf_pull_hdr(m, ipoff2, &h2_6, sizeof(h2_6), + NULL, reason, pd2.af)) { + DPFPRINTF(PF_DEBUG_MISC, + ("pf: ICMP error message too short " + "(ip6)\n")); + return (PF_DROP); + } + pd2.proto = h2_6.ip6_nxt; + pd2.src = (struct pf_addr *)&h2_6.ip6_src; + pd2.dst = (struct pf_addr *)&h2_6.ip6_dst; + pd2.ip_sum = NULL; + off2 = ipoff2 + sizeof(h2_6); + do { + switch (pd2.proto) { + case IPPROTO_FRAGMENT: + /* + * ICMPv6 error messages for + * non-first fragments + */ + REASON_SET(reason, PFRES_FRAG); + return (PF_DROP); + case IPPROTO_AH: + case IPPROTO_HOPOPTS: + case IPPROTO_ROUTING: + case IPPROTO_DSTOPTS: { + /* get next header and header length */ + struct ip6_ext opt6; + + if (!pf_pull_hdr(m, off2, &opt6, + sizeof(opt6), NULL, reason, + pd2.af)) { + DPFPRINTF(PF_DEBUG_MISC, + ("pf: ICMPv6 short opt\n")); + return (PF_DROP); + } + if (pd2.proto == IPPROTO_AH) + off2 += (opt6.ip6e_len + 2) * 4; + else + off2 += (opt6.ip6e_len + 1) * 8; + pd2.proto = opt6.ip6e_nxt; + /* goto the next header */ + break; + } + default: + terminal++; + break; + } + } while (!terminal); + break; +#endif /* INET6 */ + } + + switch (pd2.proto) { + case IPPROTO_TCP: { + struct tcphdr th; + u_int32_t seq; + struct pf_state_peer *src, *dst; + u_int8_t dws; + int copyback = 0; + + /* + * Only the first 8 bytes of the TCP header can be + * expected. Don't access any TCP header fields after + * th_seq, an ackskew test is not possible. + */ + if (!pf_pull_hdr(m, off2, &th, 8, NULL, reason, + pd2.af)) { + DPFPRINTF(PF_DEBUG_MISC, + ("pf: ICMP error message too short " + "(tcp)\n")); + return (PF_DROP); + } + + key.af = pd2.af; + key.proto = IPPROTO_TCP; + PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af); + PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af); + key.port[pd2.sidx] = th.th_sport; + key.port[pd2.didx] = th.th_dport; + + STATE_LOOKUP(kif, &key, direction, *state, pd); + + if (direction == (*state)->direction) { + src = &(*state)->dst; + dst = &(*state)->src; + } else { + src = &(*state)->src; + dst = &(*state)->dst; + } + + if (src->wscale && dst->wscale) + dws = dst->wscale & PF_WSCALE_MASK; + else + dws = 0; + + /* Demodulate sequence number */ + seq = ntohl(th.th_seq) - src->seqdiff; + if (src->seqdiff) { + pf_change_a(&th.th_seq, icmpsum, + htonl(seq), 0); + copyback = 1; + } + + if (!((*state)->state_flags & PFSTATE_SLOPPY) && + (!SEQ_GEQ(src->seqhi, seq) || + !SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)))) { + if (V_pf_status.debug >= PF_DEBUG_MISC) { + printf("pf: BAD ICMP %d:%d ", + icmptype, pd->hdr.icmp->icmp_code); + pf_print_host(pd->src, 0, pd->af); + printf(" -> "); + pf_print_host(pd->dst, 0, pd->af); + printf(" state: "); + pf_print_state(*state); + printf(" seq=%u\n", seq); + } + REASON_SET(reason, PFRES_BADSTATE); + return (PF_DROP); + } else { + if (V_pf_status.debug >= PF_DEBUG_MISC) { + printf("pf: OK ICMP %d:%d ", + icmptype, pd->hdr.icmp->icmp_code); + pf_print_host(pd->src, 0, pd->af); + printf(" -> "); + pf_print_host(pd->dst, 0, pd->af); + printf(" state: "); + pf_print_state(*state); + printf(" seq=%u\n", seq); + } + } + + /* translate source/destination address, if necessary */ + if ((*state)->key[PF_SK_WIRE] != + (*state)->key[PF_SK_STACK]) { + struct pf_state_key *nk = + (*state)->key[pd->didx]; + + if (PF_ANEQ(pd2.src, + &nk->addr[pd2.sidx], pd2.af) || + nk->port[pd2.sidx] != th.th_sport) + pf_change_icmp(pd2.src, &th.th_sport, + daddr, &nk->addr[pd2.sidx], + nk->port[pd2.sidx], NULL, + pd2.ip_sum, icmpsum, + pd->ip_sum, 0, pd2.af); + + if (PF_ANEQ(pd2.dst, + &nk->addr[pd2.didx], pd2.af) || + nk->port[pd2.didx] != th.th_dport) + pf_change_icmp(pd2.dst, &th.th_dport, + NULL, /* XXX Inbound NAT? */ + &nk->addr[pd2.didx], + nk->port[pd2.didx], NULL, + pd2.ip_sum, icmpsum, + pd->ip_sum, 0, pd2.af); + copyback = 1; + } + + if (copyback) { + switch (pd2.af) { +#ifdef INET + case AF_INET: + m_copyback(m, off, ICMP_MINLEN, + (caddr_t )pd->hdr.icmp); + m_copyback(m, ipoff2, sizeof(h2), + (caddr_t )&h2); + break; +#endif /* INET */ +#ifdef INET6 + case AF_INET6: + m_copyback(m, off, + sizeof(struct icmp6_hdr), + (caddr_t )pd->hdr.icmp6); + m_copyback(m, ipoff2, sizeof(h2_6), + (caddr_t )&h2_6); + break; +#endif /* INET6 */ + } + m_copyback(m, off2, 8, (caddr_t)&th); + } + + return (PF_PASS); + break; + } + case IPPROTO_UDP: { + struct udphdr uh; + + if (!pf_pull_hdr(m, off2, &uh, sizeof(uh), + NULL, reason, pd2.af)) { + DPFPRINTF(PF_DEBUG_MISC, + ("pf: ICMP error message too short " + "(udp)\n")); + return (PF_DROP); + } + + key.af = pd2.af; + key.proto = IPPROTO_UDP; + PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af); + PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af); + key.port[pd2.sidx] = uh.uh_sport; + key.port[pd2.didx] = uh.uh_dport; + + STATE_LOOKUP(kif, &key, direction, *state, pd); + + /* translate source/destination address, if necessary */ + if ((*state)->key[PF_SK_WIRE] != + (*state)->key[PF_SK_STACK]) { + struct pf_state_key *nk = + (*state)->key[pd->didx]; + + if (PF_ANEQ(pd2.src, + &nk->addr[pd2.sidx], pd2.af) || + nk->port[pd2.sidx] != uh.uh_sport) + pf_change_icmp(pd2.src, &uh.uh_sport, + daddr, &nk->addr[pd2.sidx], + nk->port[pd2.sidx], &uh.uh_sum, + pd2.ip_sum, icmpsum, + pd->ip_sum, 1, pd2.af); + + if (PF_ANEQ(pd2.dst, + &nk->addr[pd2.didx], pd2.af) || + nk->port[pd2.didx] != uh.uh_dport) + pf_change_icmp(pd2.dst, &uh.uh_dport, + NULL, /* XXX Inbound NAT? */ + &nk->addr[pd2.didx], + nk->port[pd2.didx], &uh.uh_sum, + pd2.ip_sum, icmpsum, + pd->ip_sum, 1, pd2.af); + + switch (pd2.af) { +#ifdef INET + case AF_INET: + m_copyback(m, off, ICMP_MINLEN, + (caddr_t )pd->hdr.icmp); + m_copyback(m, ipoff2, sizeof(h2), (caddr_t)&h2); + break; +#endif /* INET */ +#ifdef INET6 + case AF_INET6: + m_copyback(m, off, + sizeof(struct icmp6_hdr), + (caddr_t )pd->hdr.icmp6); + m_copyback(m, ipoff2, sizeof(h2_6), + (caddr_t )&h2_6); + break; +#endif /* INET6 */ + } + m_copyback(m, off2, sizeof(uh), (caddr_t)&uh); + } + return (PF_PASS); + break; + } +#ifdef INET + case IPPROTO_ICMP: { + struct icmp iih; + + if (!pf_pull_hdr(m, off2, &iih, ICMP_MINLEN, + NULL, reason, pd2.af)) { + DPFPRINTF(PF_DEBUG_MISC, + ("pf: ICMP error message too short i" + "(icmp)\n")); + return (PF_DROP); + } + + key.af = pd2.af; + key.proto = IPPROTO_ICMP; + PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af); + PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af); + key.port[0] = key.port[1] = iih.icmp_id; + + STATE_LOOKUP(kif, &key, direction, *state, pd); + + /* translate source/destination address, if necessary */ + if ((*state)->key[PF_SK_WIRE] != + (*state)->key[PF_SK_STACK]) { + struct pf_state_key *nk = + (*state)->key[pd->didx]; + + if (PF_ANEQ(pd2.src, + &nk->addr[pd2.sidx], pd2.af) || + nk->port[pd2.sidx] != iih.icmp_id) + pf_change_icmp(pd2.src, &iih.icmp_id, + daddr, &nk->addr[pd2.sidx], + nk->port[pd2.sidx], NULL, + pd2.ip_sum, icmpsum, + pd->ip_sum, 0, AF_INET); + + if (PF_ANEQ(pd2.dst, + &nk->addr[pd2.didx], pd2.af) || + nk->port[pd2.didx] != iih.icmp_id) + pf_change_icmp(pd2.dst, &iih.icmp_id, + NULL, /* XXX Inbound NAT? */ + &nk->addr[pd2.didx], + nk->port[pd2.didx], NULL, + pd2.ip_sum, icmpsum, + pd->ip_sum, 0, AF_INET); + + m_copyback(m, off, ICMP_MINLEN, (caddr_t)pd->hdr.icmp); + m_copyback(m, ipoff2, sizeof(h2), (caddr_t)&h2); + m_copyback(m, off2, ICMP_MINLEN, (caddr_t)&iih); + } + return (PF_PASS); + break; + } +#endif /* INET */ +#ifdef INET6 + case IPPROTO_ICMPV6: { + struct icmp6_hdr iih; + + if (!pf_pull_hdr(m, off2, &iih, + sizeof(struct icmp6_hdr), NULL, reason, pd2.af)) { + DPFPRINTF(PF_DEBUG_MISC, + ("pf: ICMP error message too short " + "(icmp6)\n")); + return (PF_DROP); + } + + key.af = pd2.af; + key.proto = IPPROTO_ICMPV6; + PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af); + PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af); + key.port[0] = key.port[1] = iih.icmp6_id; + + STATE_LOOKUP(kif, &key, direction, *state, pd); + + /* translate source/destination address, if necessary */ + if ((*state)->key[PF_SK_WIRE] != + (*state)->key[PF_SK_STACK]) { + struct pf_state_key *nk = + (*state)->key[pd->didx]; + + if (PF_ANEQ(pd2.src, + &nk->addr[pd2.sidx], pd2.af) || + nk->port[pd2.sidx] != iih.icmp6_id) + pf_change_icmp(pd2.src, &iih.icmp6_id, + daddr, &nk->addr[pd2.sidx], + nk->port[pd2.sidx], NULL, + pd2.ip_sum, icmpsum, + pd->ip_sum, 0, AF_INET6); + + if (PF_ANEQ(pd2.dst, + &nk->addr[pd2.didx], pd2.af) || + nk->port[pd2.didx] != iih.icmp6_id) + pf_change_icmp(pd2.dst, &iih.icmp6_id, + NULL, /* XXX Inbound NAT? */ + &nk->addr[pd2.didx], + nk->port[pd2.didx], NULL, + pd2.ip_sum, icmpsum, + pd->ip_sum, 0, AF_INET6); + + m_copyback(m, off, sizeof(struct icmp6_hdr), + (caddr_t)pd->hdr.icmp6); + m_copyback(m, ipoff2, sizeof(h2_6), (caddr_t)&h2_6); + m_copyback(m, off2, sizeof(struct icmp6_hdr), + (caddr_t)&iih); + } + return (PF_PASS); + break; + } +#endif /* INET6 */ + default: { + key.af = pd2.af; + key.proto = pd2.proto; + PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af); + PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af); + key.port[0] = key.port[1] = 0; + + STATE_LOOKUP(kif, &key, direction, *state, pd); + + /* translate source/destination address, if necessary */ + if ((*state)->key[PF_SK_WIRE] != + (*state)->key[PF_SK_STACK]) { + struct pf_state_key *nk = + (*state)->key[pd->didx]; + + if (PF_ANEQ(pd2.src, + &nk->addr[pd2.sidx], pd2.af)) + pf_change_icmp(pd2.src, NULL, daddr, + &nk->addr[pd2.sidx], 0, NULL, + pd2.ip_sum, icmpsum, + pd->ip_sum, 0, pd2.af); + + if (PF_ANEQ(pd2.dst, + &nk->addr[pd2.didx], pd2.af)) + pf_change_icmp(pd2.src, NULL, + NULL, /* XXX Inbound NAT? */ + &nk->addr[pd2.didx], 0, NULL, + pd2.ip_sum, icmpsum, + pd->ip_sum, 0, pd2.af); + + switch (pd2.af) { +#ifdef INET + case AF_INET: + m_copyback(m, off, ICMP_MINLEN, + (caddr_t)pd->hdr.icmp); + m_copyback(m, ipoff2, sizeof(h2), (caddr_t)&h2); + break; +#endif /* INET */ +#ifdef INET6 + case AF_INET6: + m_copyback(m, off, + sizeof(struct icmp6_hdr), + (caddr_t )pd->hdr.icmp6); + m_copyback(m, ipoff2, sizeof(h2_6), + (caddr_t )&h2_6); + break; +#endif /* INET6 */ + } + } + return (PF_PASS); + break; + } + } + } +} + +static int +pf_test_state_other(struct pf_state **state, int direction, struct pfi_kif *kif, + struct mbuf *m, struct pf_pdesc *pd) +{ + struct pf_state_peer *src, *dst; + struct pf_state_key_cmp key; + + bzero(&key, sizeof(key)); + key.af = pd->af; + key.proto = pd->proto; + if (direction == PF_IN) { + PF_ACPY(&key.addr[0], pd->src, key.af); + PF_ACPY(&key.addr[1], pd->dst, key.af); + key.port[0] = key.port[1] = 0; + } else { + PF_ACPY(&key.addr[1], pd->src, key.af); + PF_ACPY(&key.addr[0], pd->dst, key.af); + key.port[1] = key.port[0] = 0; + } + + STATE_LOOKUP(kif, &key, direction, *state, pd); + + if (direction == (*state)->direction) { + src = &(*state)->src; + dst = &(*state)->dst; + } else { + src = &(*state)->dst; + dst = &(*state)->src; + } + + /* update states */ + if (src->state < PFOTHERS_SINGLE) + src->state = PFOTHERS_SINGLE; + if (dst->state == PFOTHERS_SINGLE) + dst->state = PFOTHERS_MULTIPLE; + + /* update expire time */ + (*state)->expire = time_uptime; + if (src->state == PFOTHERS_MULTIPLE && dst->state == PFOTHERS_MULTIPLE) + (*state)->timeout = PFTM_OTHER_MULTIPLE; + else + (*state)->timeout = PFTM_OTHER_SINGLE; + + /* translate source/destination address, if necessary */ + if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) { + struct pf_state_key *nk = (*state)->key[pd->didx]; + + KASSERT(nk, ("%s: nk is null", __func__)); + KASSERT(pd, ("%s: pd is null", __func__)); + KASSERT(pd->src, ("%s: pd->src is null", __func__)); + KASSERT(pd->dst, ("%s: pd->dst is null", __func__)); + switch (pd->af) { +#ifdef INET + case AF_INET: + if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], AF_INET)) + pf_change_a(&pd->src->v4.s_addr, + pd->ip_sum, + nk->addr[pd->sidx].v4.s_addr, + 0); + + + if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], AF_INET)) + pf_change_a(&pd->dst->v4.s_addr, + pd->ip_sum, + nk->addr[pd->didx].v4.s_addr, + 0); + + break; +#endif /* INET */ +#ifdef INET6 + case AF_INET6: + if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], AF_INET)) + PF_ACPY(pd->src, &nk->addr[pd->sidx], pd->af); + + if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], AF_INET)) + PF_ACPY(pd->dst, &nk->addr[pd->didx], pd->af); +#endif /* INET6 */ + } + } + return (PF_PASS); +} + +/* + * ipoff and off are measured from the start of the mbuf chain. + * h must be at "ipoff" on the mbuf chain. + */ +void * +pf_pull_hdr(struct mbuf *m, int off, void *p, int len, + u_short *actionp, u_short *reasonp, sa_family_t af) +{ + switch (af) { +#ifdef INET + case AF_INET: { + struct ip *h = mtod(m, struct ip *); + u_int16_t fragoff = (ntohs(h->ip_off) & IP_OFFMASK) << 3; + + if (fragoff) { + if (fragoff >= len) + ACTION_SET(actionp, PF_PASS); + else { + ACTION_SET(actionp, PF_DROP); + REASON_SET(reasonp, PFRES_FRAG); + } + return (NULL); + } + if (m->m_pkthdr.len < off + len || + ntohs(h->ip_len) < off + len) { + ACTION_SET(actionp, PF_DROP); + REASON_SET(reasonp, PFRES_SHORT); + return (NULL); + } + break; + } +#endif /* INET */ +#ifdef INET6 + case AF_INET6: { + struct ip6_hdr *h = mtod(m, struct ip6_hdr *); + + if (m->m_pkthdr.len < off + len || + (ntohs(h->ip6_plen) + sizeof(struct ip6_hdr)) < + (unsigned)(off + len)) { + ACTION_SET(actionp, PF_DROP); + REASON_SET(reasonp, PFRES_SHORT); + return (NULL); + } + break; + } +#endif /* INET6 */ + } + m_copydata(m, off, len, p); + return (p); +} + +int +pf_routable(struct pf_addr *addr, sa_family_t af, struct pfi_kif *kif, + int rtableid) +{ +#ifdef RADIX_MPATH + struct radix_node_head *rnh; +#endif + struct sockaddr_in *dst; + int ret = 1; + int check_mpath; +#ifdef INET6 + struct sockaddr_in6 *dst6; + struct route_in6 ro; +#else + struct route ro; +#endif + struct radix_node *rn; + struct rtentry *rt; + struct ifnet *ifp; + + check_mpath = 0; +#ifdef RADIX_MPATH + /* XXX: stick to table 0 for now */ + rnh = rt_tables_get_rnh(0, af); + if (rnh != NULL && rn_mpath_capable(rnh)) + check_mpath = 1; +#endif + bzero(&ro, sizeof(ro)); + switch (af) { + case AF_INET: + dst = satosin(&ro.ro_dst); + dst->sin_family = AF_INET; + dst->sin_len = sizeof(*dst); + dst->sin_addr = addr->v4; + break; +#ifdef INET6 + case AF_INET6: + /* + * Skip check for addresses with embedded interface scope, + * as they would always match anyway. + */ + if (IN6_IS_SCOPE_EMBED(&addr->v6)) + goto out; + dst6 = (struct sockaddr_in6 *)&ro.ro_dst; + dst6->sin6_family = AF_INET6; + dst6->sin6_len = sizeof(*dst6); + dst6->sin6_addr = addr->v6; + break; +#endif /* INET6 */ + default: + return (0); + } + + /* Skip checks for ipsec interfaces */ + if (kif != NULL && kif->pfik_ifp->if_type == IFT_ENC) + goto out; + + switch (af) { +#ifdef INET6 + case AF_INET6: + in6_rtalloc_ign(&ro, 0, rtableid); + break; +#endif +#ifdef INET + case AF_INET: + in_rtalloc_ign((struct route *)&ro, 0, rtableid); + break; +#endif + default: + rtalloc_ign((struct route *)&ro, 0); /* No/default FIB. */ + break; + } + + if (ro.ro_rt != NULL) { + /* No interface given, this is a no-route check */ + if (kif == NULL) + goto out; + + if (kif->pfik_ifp == NULL) { + ret = 0; + goto out; + } + + /* Perform uRPF check if passed input interface */ + ret = 0; + rn = (struct radix_node *)ro.ro_rt; + do { + rt = (struct rtentry *)rn; + ifp = rt->rt_ifp; + + if (kif->pfik_ifp == ifp) + ret = 1; +#ifdef RADIX_MPATH + rn = rn_mpath_next(rn); +#endif + } while (check_mpath == 1 && rn != NULL && ret == 0); + } else + ret = 0; +out: + if (ro.ro_rt != NULL) + RTFREE(ro.ro_rt); + return (ret); +} + +#ifdef INET +static void +pf_route(struct mbuf **m, struct pf_rule *r, int dir, struct ifnet *oifp, + struct pf_state *s, struct pf_pdesc *pd) +{ + struct mbuf *m0, *m1; + struct sockaddr_in dst; + struct ip *ip; + struct ifnet *ifp = NULL; + struct pf_addr naddr; + struct pf_src_node *sn = NULL; + int error = 0; + int sw_csum; + + KASSERT(m && *m && r && oifp, ("%s: invalid parameters", __func__)); + KASSERT(dir == PF_IN || dir == PF_OUT, ("%s: invalid direction", + __func__)); + + if ((pd->pf_mtag == NULL && + ((pd->pf_mtag = pf_get_mtag(*m)) == NULL)) || + pd->pf_mtag->routed++ > 3) { + m0 = *m; + *m = NULL; + goto bad_locked; + } + + if (r->rt == PF_DUPTO) { + if ((m0 = m_dup(*m, M_NOWAIT)) == NULL) { + if (s) + PF_STATE_UNLOCK(s); + return; + } + } else { + if ((r->rt == PF_REPLYTO) == (r->direction == dir)) { + if (s) + PF_STATE_UNLOCK(s); + return; + } + m0 = *m; + } + + ip = mtod(m0, struct ip *); + + bzero(&dst, sizeof(dst)); + dst.sin_family = AF_INET; + dst.sin_len = sizeof(dst); + dst.sin_addr = ip->ip_dst; + + if (r->rt == PF_FASTROUTE) { + struct rtentry *rt; + + if (s) + PF_STATE_UNLOCK(s); + rt = rtalloc1_fib(sintosa(&dst), 0, 0, M_GETFIB(m0)); + if (rt == NULL) { + RTFREE_LOCKED(rt); + KMOD_IPSTAT_INC(ips_noroute); + error = EHOSTUNREACH; + goto bad; + } + + ifp = rt->rt_ifp; + rt->rt_rmx.rmx_pksent++; + + if (rt->rt_flags & RTF_GATEWAY) + bcopy(satosin(rt->rt_gateway), &dst, sizeof(dst)); + RTFREE_LOCKED(rt); + } else { + if (TAILQ_EMPTY(&r->rpool.list)) { + DPFPRINTF(PF_DEBUG_URGENT, + ("%s: TAILQ_EMPTY(&r->rpool.list)\n", __func__)); + goto bad_locked; + } + if (s == NULL) { + pf_map_addr(AF_INET, r, (struct pf_addr *)&ip->ip_src, + &naddr, NULL, &sn); + if (!PF_AZERO(&naddr, AF_INET)) + dst.sin_addr.s_addr = naddr.v4.s_addr; + ifp = r->rpool.cur->kif ? + r->rpool.cur->kif->pfik_ifp : NULL; + } else { + if (!PF_AZERO(&s->rt_addr, AF_INET)) + dst.sin_addr.s_addr = + s->rt_addr.v4.s_addr; + ifp = s->rt_kif ? s->rt_kif->pfik_ifp : NULL; + PF_STATE_UNLOCK(s); + } + } + if (ifp == NULL) + goto bad; + + if (oifp != ifp) { + if (pf_test(PF_OUT, ifp, &m0, NULL) != PF_PASS) + goto bad; + else if (m0 == NULL) + goto done; + if (m0->m_len < sizeof(struct ip)) { + DPFPRINTF(PF_DEBUG_URGENT, + ("%s: m0->m_len < sizeof(struct ip)\n", __func__)); + goto bad; + } + ip = mtod(m0, struct ip *); + } + + if (ifp->if_flags & IFF_LOOPBACK) + m0->m_flags |= M_SKIP_FIREWALL; + + /* Back to host byte order. */ + ip->ip_len = ntohs(ip->ip_len); + ip->ip_off = ntohs(ip->ip_off); + + /* Copied from FreeBSD 10.0-CURRENT ip_output. */ + m0->m_pkthdr.csum_flags |= CSUM_IP; + sw_csum = m0->m_pkthdr.csum_flags & ~ifp->if_hwassist; + if (sw_csum & CSUM_DELAY_DATA) { + in_delayed_cksum(m0); + sw_csum &= ~CSUM_DELAY_DATA; + } +#ifdef SCTP + if (sw_csum & CSUM_SCTP) { + sctp_delayed_cksum(m, (uint32_t)(ip->ip_hl << 2)); + sw_csum &= ~CSUM_SCTP; + } +#endif + m0->m_pkthdr.csum_flags &= ifp->if_hwassist; + + /* + * If small enough for interface, or the interface will take + * care of the fragmentation for us, we can just send directly. + */ + if (ip->ip_len <= ifp->if_mtu || + (m0->m_pkthdr.csum_flags & ifp->if_hwassist & CSUM_TSO) != 0 || + ((ip->ip_off & IP_DF) == 0 && (ifp->if_hwassist & CSUM_FRAGMENT))) { + ip->ip_len = htons(ip->ip_len); + ip->ip_off = htons(ip->ip_off); + ip->ip_sum = 0; + if (sw_csum & CSUM_DELAY_IP) + ip->ip_sum = in_cksum(m0, ip->ip_hl << 2); + m0->m_flags &= ~(M_PROTOFLAGS); + error = (*ifp->if_output)(ifp, m0, sintosa(&dst), NULL); + goto done; + } + + /* Balk when DF bit is set or the interface didn't support TSO. */ + if ((ip->ip_off & IP_DF) || (m0->m_pkthdr.csum_flags & CSUM_TSO)) { + error = EMSGSIZE; + KMOD_IPSTAT_INC(ips_cantfrag); + if (r->rt != PF_DUPTO) { + icmp_error(m0, ICMP_UNREACH, ICMP_UNREACH_NEEDFRAG, 0, + ifp->if_mtu); + goto done; + } else + goto bad; + } + + error = ip_fragment(ip, &m0, ifp->if_mtu, ifp->if_hwassist, sw_csum); + if (error) + goto bad; + + for (; m0; m0 = m1) { + m1 = m0->m_nextpkt; + m0->m_nextpkt = NULL; + if (error == 0) { + m0->m_flags &= ~(M_PROTOFLAGS); + error = (*ifp->if_output)(ifp, m0, sintosa(&dst), NULL); + } else + m_freem(m0); + } + + if (error == 0) + KMOD_IPSTAT_INC(ips_fragmented); + +done: + if (r->rt != PF_DUPTO) + *m = NULL; + return; + +bad_locked: + if (s) + PF_STATE_UNLOCK(s); +bad: + m_freem(m0); + goto done; +} +#endif /* INET */ + +#ifdef INET6 +static void +pf_route6(struct mbuf **m, struct pf_rule *r, int dir, struct ifnet *oifp, + struct pf_state *s, struct pf_pdesc *pd) +{ + struct mbuf *m0; + struct sockaddr_in6 dst; + struct ip6_hdr *ip6; + struct ifnet *ifp = NULL; + struct pf_addr naddr; + struct pf_src_node *sn = NULL; + + KASSERT(m && *m && r && oifp, ("%s: invalid parameters", __func__)); + KASSERT(dir == PF_IN || dir == PF_OUT, ("%s: invalid direction", + __func__)); + + if ((pd->pf_mtag == NULL && + ((pd->pf_mtag = pf_get_mtag(*m)) == NULL)) || + pd->pf_mtag->routed++ > 3) { + m0 = *m; + *m = NULL; + goto bad_locked; + } + + if (r->rt == PF_DUPTO) { + if ((m0 = m_dup(*m, M_NOWAIT)) == NULL) { + if (s) + PF_STATE_UNLOCK(s); + return; + } + } else { + if ((r->rt == PF_REPLYTO) == (r->direction == dir)) { + if (s) + PF_STATE_UNLOCK(s); + return; + } + m0 = *m; + } + + ip6 = mtod(m0, struct ip6_hdr *); + + bzero(&dst, sizeof(dst)); + dst.sin6_family = AF_INET6; + dst.sin6_len = sizeof(dst); + dst.sin6_addr = ip6->ip6_dst; + + /* Cheat. XXX why only in the v6 case??? */ + if (r->rt == PF_FASTROUTE) { + if (s) + PF_STATE_UNLOCK(s); + m0->m_flags |= M_SKIP_FIREWALL; + ip6_output(m0, NULL, NULL, 0, NULL, NULL, NULL); + return; + } + + if (TAILQ_EMPTY(&r->rpool.list)) { + DPFPRINTF(PF_DEBUG_URGENT, + ("%s: TAILQ_EMPTY(&r->rpool.list)\n", __func__)); + goto bad_locked; + } + if (s == NULL) { + pf_map_addr(AF_INET6, r, (struct pf_addr *)&ip6->ip6_src, + &naddr, NULL, &sn); + if (!PF_AZERO(&naddr, AF_INET6)) + PF_ACPY((struct pf_addr *)&dst.sin6_addr, + &naddr, AF_INET6); + ifp = r->rpool.cur->kif ? r->rpool.cur->kif->pfik_ifp : NULL; + } else { + if (!PF_AZERO(&s->rt_addr, AF_INET6)) + PF_ACPY((struct pf_addr *)&dst.sin6_addr, + &s->rt_addr, AF_INET6); + ifp = s->rt_kif ? s->rt_kif->pfik_ifp : NULL; + } + + if (s) + PF_STATE_UNLOCK(s); + + if (ifp == NULL) + goto bad; + + if (oifp != ifp) { + if (pf_test6(PF_OUT, ifp, &m0, NULL) != PF_PASS) + goto bad; + else if (m0 == NULL) + goto done; + if (m0->m_len < sizeof(struct ip6_hdr)) { + DPFPRINTF(PF_DEBUG_URGENT, + ("%s: m0->m_len < sizeof(struct ip6_hdr)\n", + __func__)); + goto bad; + } + ip6 = mtod(m0, struct ip6_hdr *); + } + + if (ifp->if_flags & IFF_LOOPBACK) + m0->m_flags |= M_SKIP_FIREWALL; + + /* + * If the packet is too large for the outgoing interface, + * send back an icmp6 error. + */ + if (IN6_IS_SCOPE_EMBED(&dst.sin6_addr)) + dst.sin6_addr.s6_addr16[1] = htons(ifp->if_index); + if ((u_long)m0->m_pkthdr.len <= ifp->if_mtu) + nd6_output(ifp, ifp, m0, &dst, NULL); + else { + in6_ifstat_inc(ifp, ifs6_in_toobig); + if (r->rt != PF_DUPTO) + icmp6_error(m0, ICMP6_PACKET_TOO_BIG, 0, ifp->if_mtu); + else + goto bad; + } + +done: + if (r->rt != PF_DUPTO) + *m = NULL; + return; + +bad_locked: + if (s) + PF_STATE_UNLOCK(s); +bad: + m_freem(m0); + goto done; +} +#endif /* INET6 */ + +/* + * FreeBSD supports cksum offloads for the following drivers. + * em(4), fxp(4), ixgb(4), lge(4), ndis(4), nge(4), re(4), + * ti(4), txp(4), xl(4) + * + * CSUM_DATA_VALID | CSUM_PSEUDO_HDR : + * network driver performed cksum including pseudo header, need to verify + * csum_data + * CSUM_DATA_VALID : + * network driver performed cksum, needs to additional pseudo header + * cksum computation with partial csum_data(i.e. lack of H/W support for + * pseudo header, for instance hme(4), sk(4) and possibly gem(4)) + * + * After validating the cksum of packet, set both flag CSUM_DATA_VALID and + * CSUM_PSEUDO_HDR in order to avoid recomputation of the cksum in upper + * TCP/UDP layer. + * Also, set csum_data to 0xffff to force cksum validation. + */ +static int +pf_check_proto_cksum(struct mbuf *m, int off, int len, u_int8_t p, sa_family_t af) +{ + u_int16_t sum = 0; + int hw_assist = 0; + struct ip *ip; + + if (off < sizeof(struct ip) || len < sizeof(struct udphdr)) + return (1); + if (m->m_pkthdr.len < off + len) + return (1); + + switch (p) { + case IPPROTO_TCP: + if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) { + if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) { + sum = m->m_pkthdr.csum_data; + } else { + ip = mtod(m, struct ip *); + sum = in_pseudo(ip->ip_src.s_addr, + ip->ip_dst.s_addr, htonl((u_short)len + + m->m_pkthdr.csum_data + IPPROTO_TCP)); + } + sum ^= 0xffff; + ++hw_assist; + } + break; + case IPPROTO_UDP: + if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) { + if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) { + sum = m->m_pkthdr.csum_data; + } else { + ip = mtod(m, struct ip *); + sum = in_pseudo(ip->ip_src.s_addr, + ip->ip_dst.s_addr, htonl((u_short)len + + m->m_pkthdr.csum_data + IPPROTO_UDP)); + } + sum ^= 0xffff; + ++hw_assist; + } + break; + case IPPROTO_ICMP: +#ifdef INET6 + case IPPROTO_ICMPV6: +#endif /* INET6 */ + break; + default: + return (1); + } + + if (!hw_assist) { + switch (af) { + case AF_INET: + if (p == IPPROTO_ICMP) { + if (m->m_len < off) + return (1); + m->m_data += off; + m->m_len -= off; + sum = in_cksum(m, len); + m->m_data -= off; + m->m_len += off; + } else { + if (m->m_len < sizeof(struct ip)) + return (1); + sum = in4_cksum(m, p, off, len); + } + break; +#ifdef INET6 + case AF_INET6: + if (m->m_len < sizeof(struct ip6_hdr)) + return (1); + sum = in6_cksum(m, p, off, len); + break; +#endif /* INET6 */ + default: + return (1); + } + } + if (sum) { + switch (p) { + case IPPROTO_TCP: + { + KMOD_TCPSTAT_INC(tcps_rcvbadsum); + break; + } + case IPPROTO_UDP: + { + KMOD_UDPSTAT_INC(udps_badsum); + break; + } +#ifdef INET + case IPPROTO_ICMP: + { + KMOD_ICMPSTAT_INC(icps_checksum); + break; + } +#endif +#ifdef INET6 + case IPPROTO_ICMPV6: + { + KMOD_ICMP6STAT_INC(icp6s_checksum); + break; + } +#endif /* INET6 */ + } + return (1); + } else { + if (p == IPPROTO_TCP || p == IPPROTO_UDP) { + m->m_pkthdr.csum_flags |= + (CSUM_DATA_VALID | CSUM_PSEUDO_HDR); + m->m_pkthdr.csum_data = 0xffff; + } + } + return (0); +} + + +#ifdef INET +int +pf_test(int dir, struct ifnet *ifp, struct mbuf **m0, struct inpcb *inp) +{ + struct pfi_kif *kif; + u_short action, reason = 0, log = 0; + struct mbuf *m = *m0; + struct ip *h = NULL; + struct m_tag *ipfwtag; + struct pf_rule *a = NULL, *r = &V_pf_default_rule, *tr, *nr; + struct pf_state *s = NULL; + struct pf_ruleset *ruleset = NULL; + struct pf_pdesc pd; + int off, dirndx, pqid = 0; + + M_ASSERTPKTHDR(m); + + if (!V_pf_status.running) + return (PF_PASS); + + memset(&pd, 0, sizeof(pd)); + + kif = (struct pfi_kif *)ifp->if_pf_kif; + + if (kif == NULL) { + DPFPRINTF(PF_DEBUG_URGENT, + ("pf_test: kif == NULL, if_xname %s\n", ifp->if_xname)); + return (PF_DROP); + } + if (kif->pfik_flags & PFI_IFLAG_SKIP) + return (PF_PASS); + + if (m->m_flags & M_SKIP_FIREWALL) + return (PF_PASS); + + if (m->m_pkthdr.len < (int)sizeof(struct ip)) { + action = PF_DROP; + REASON_SET(&reason, PFRES_SHORT); + log = 1; + goto done; + } + + pd.pf_mtag = pf_find_mtag(m); + + PF_RULES_RLOCK(); + + if (ip_divert_ptr != NULL && + ((ipfwtag = m_tag_locate(m, MTAG_IPFW_RULE, 0, NULL)) != NULL)) { + struct ipfw_rule_ref *rr = (struct ipfw_rule_ref *)(ipfwtag+1); + if (rr->info & IPFW_IS_DIVERT && rr->rulenum == 0) { + if (pd.pf_mtag == NULL && + ((pd.pf_mtag = pf_get_mtag(m)) == NULL)) { + action = PF_DROP; + goto done; + } + pd.pf_mtag->flags |= PF_PACKET_LOOPED; + m_tag_delete(m, ipfwtag); + } + if (pd.pf_mtag && pd.pf_mtag->flags & PF_FASTFWD_OURS_PRESENT) { + m->m_flags |= M_FASTFWD_OURS; + pd.pf_mtag->flags &= ~PF_FASTFWD_OURS_PRESENT; + } + } else if (pf_normalize_ip(m0, dir, kif, &reason, &pd) != PF_PASS) { + /* We do IP header normalization and packet reassembly here */ + action = PF_DROP; + goto done; + } + m = *m0; /* pf_normalize messes with m0 */ + h = mtod(m, struct ip *); + + off = h->ip_hl << 2; + if (off < (int)sizeof(struct ip)) { + action = PF_DROP; + REASON_SET(&reason, PFRES_SHORT); + log = 1; + goto done; + } + + pd.src = (struct pf_addr *)&h->ip_src; + pd.dst = (struct pf_addr *)&h->ip_dst; + pd.sport = pd.dport = NULL; + pd.ip_sum = &h->ip_sum; + pd.proto_sum = NULL; + pd.proto = h->ip_p; + pd.dir = dir; + pd.sidx = (dir == PF_IN) ? 0 : 1; + pd.didx = (dir == PF_IN) ? 1 : 0; + pd.af = AF_INET; + pd.tos = h->ip_tos; + pd.tot_len = ntohs(h->ip_len); + + /* handle fragments that didn't get reassembled by normalization */ + if (h->ip_off & htons(IP_MF | IP_OFFMASK)) { + action = pf_test_fragment(&r, dir, kif, m, h, + &pd, &a, &ruleset); + goto done; + } + + switch (h->ip_p) { + + case IPPROTO_TCP: { + struct tcphdr th; + + pd.hdr.tcp = &th; + if (!pf_pull_hdr(m, off, &th, sizeof(th), + &action, &reason, AF_INET)) { + log = action != PF_PASS; + goto done; + } + pd.p_len = pd.tot_len - off - (th.th_off << 2); + if ((th.th_flags & TH_ACK) && pd.p_len == 0) + pqid = 1; + action = pf_normalize_tcp(dir, kif, m, 0, off, h, &pd); + if (action == PF_DROP) + goto done; + action = pf_test_state_tcp(&s, dir, kif, m, off, h, &pd, + &reason); + if (action == PF_PASS) { + if (pfsync_update_state_ptr != NULL) + pfsync_update_state_ptr(s); + r = s->rule.ptr; + a = s->anchor.ptr; + log = s->log; + } else if (s == NULL) + action = pf_test_rule(&r, &s, dir, kif, m, off, &pd, + &a, &ruleset, inp); + break; + } + + case IPPROTO_UDP: { + struct udphdr uh; + + pd.hdr.udp = &uh; + if (!pf_pull_hdr(m, off, &uh, sizeof(uh), + &action, &reason, AF_INET)) { + log = action != PF_PASS; + goto done; + } + if (uh.uh_dport == 0 || + ntohs(uh.uh_ulen) > m->m_pkthdr.len - off || + ntohs(uh.uh_ulen) < sizeof(struct udphdr)) { + action = PF_DROP; + REASON_SET(&reason, PFRES_SHORT); + goto done; + } + action = pf_test_state_udp(&s, dir, kif, m, off, h, &pd); + if (action == PF_PASS) { + if (pfsync_update_state_ptr != NULL) + pfsync_update_state_ptr(s); + r = s->rule.ptr; + a = s->anchor.ptr; + log = s->log; + } else if (s == NULL) + action = pf_test_rule(&r, &s, dir, kif, m, off, &pd, + &a, &ruleset, inp); + break; + } + + case IPPROTO_ICMP: { + struct icmp ih; + + pd.hdr.icmp = &ih; + if (!pf_pull_hdr(m, off, &ih, ICMP_MINLEN, + &action, &reason, AF_INET)) { + log = action != PF_PASS; + goto done; + } + action = pf_test_state_icmp(&s, dir, kif, m, off, h, &pd, + &reason); + if (action == PF_PASS) { + if (pfsync_update_state_ptr != NULL) + pfsync_update_state_ptr(s); + r = s->rule.ptr; + a = s->anchor.ptr; + log = s->log; + } else if (s == NULL) + action = pf_test_rule(&r, &s, dir, kif, m, off, &pd, + &a, &ruleset, inp); + break; + } + +#ifdef INET6 + case IPPROTO_ICMPV6: { + action = PF_DROP; + DPFPRINTF(PF_DEBUG_MISC, + ("pf: dropping IPv4 packet with ICMPv6 payload\n")); + goto done; + } +#endif + + default: + action = pf_test_state_other(&s, dir, kif, m, &pd); + if (action == PF_PASS) { + if (pfsync_update_state_ptr != NULL) + pfsync_update_state_ptr(s); + r = s->rule.ptr; + a = s->anchor.ptr; + log = s->log; + } else if (s == NULL) + action = pf_test_rule(&r, &s, dir, kif, m, off, &pd, + &a, &ruleset, inp); + break; + } + +done: + PF_RULES_RUNLOCK(); + if (action == PF_PASS && h->ip_hl > 5 && + !((s && s->state_flags & PFSTATE_ALLOWOPTS) || r->allow_opts)) { + action = PF_DROP; + REASON_SET(&reason, PFRES_IPOPTIONS); + log = 1; + DPFPRINTF(PF_DEBUG_MISC, + ("pf: dropping packet with ip options\n")); + } + + if (s && s->tag > 0 && pf_tag_packet(m, &pd, s->tag)) { + action = PF_DROP; + REASON_SET(&reason, PFRES_MEMORY); + } + if (r->rtableid >= 0) + M_SETFIB(m, r->rtableid); + +#ifdef ALTQ + if (action == PF_PASS && r->qid) { + if (pd.pf_mtag == NULL && + ((pd.pf_mtag = pf_get_mtag(m)) == NULL)) { + action = PF_DROP; + REASON_SET(&reason, PFRES_MEMORY); + } + if (pqid || (pd.tos & IPTOS_LOWDELAY)) + pd.pf_mtag->qid = r->pqid; + else + pd.pf_mtag->qid = r->qid; + /* add hints for ecn */ + pd.pf_mtag->hdr = h; + + } +#endif /* ALTQ */ + + /* + * connections redirected to loopback should not match sockets + * bound specifically to loopback due to security implications, + * see tcp_input() and in_pcblookup_listen(). + */ + if (dir == PF_IN && action == PF_PASS && (pd.proto == IPPROTO_TCP || + pd.proto == IPPROTO_UDP) && s != NULL && s->nat_rule.ptr != NULL && + (s->nat_rule.ptr->action == PF_RDR || + s->nat_rule.ptr->action == PF_BINAT) && + (ntohl(pd.dst->v4.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) + m->m_flags |= M_SKIP_FIREWALL; + + if (action == PF_PASS && r->divert.port && ip_divert_ptr != NULL && + !PACKET_LOOPED(&pd)) { + + ipfwtag = m_tag_alloc(MTAG_IPFW_RULE, 0, + sizeof(struct ipfw_rule_ref), M_NOWAIT | M_ZERO); + if (ipfwtag != NULL) { + ((struct ipfw_rule_ref *)(ipfwtag+1))->info = + ntohs(r->divert.port); + ((struct ipfw_rule_ref *)(ipfwtag+1))->rulenum = dir; + + if (s) + PF_STATE_UNLOCK(s); + + m_tag_prepend(m, ipfwtag); + if (m->m_flags & M_FASTFWD_OURS) { + if (pd.pf_mtag == NULL && + ((pd.pf_mtag = pf_get_mtag(m)) == NULL)) { + action = PF_DROP; + REASON_SET(&reason, PFRES_MEMORY); + log = 1; + DPFPRINTF(PF_DEBUG_MISC, + ("pf: failed to allocate tag\n")); + } + pd.pf_mtag->flags |= PF_FASTFWD_OURS_PRESENT; + m->m_flags &= ~M_FASTFWD_OURS; + } + ip_divert_ptr(*m0, dir == PF_IN ? DIR_IN : DIR_OUT); + *m0 = NULL; + + return (action); + } else { + /* XXX: ipfw has the same behaviour! */ + action = PF_DROP; + REASON_SET(&reason, PFRES_MEMORY); + log = 1; + DPFPRINTF(PF_DEBUG_MISC, + ("pf: failed to allocate divert tag\n")); + } + } + + if (log) { + struct pf_rule *lr; + + if (s != NULL && s->nat_rule.ptr != NULL && + s->nat_rule.ptr->log & PF_LOG_ALL) + lr = s->nat_rule.ptr; + else + lr = r; + PFLOG_PACKET(kif, m, AF_INET, dir, reason, lr, a, ruleset, &pd, + (s == NULL)); + } + + kif->pfik_bytes[0][dir == PF_OUT][action != PF_PASS] += pd.tot_len; + kif->pfik_packets[0][dir == PF_OUT][action != PF_PASS]++; + + if (action == PF_PASS || r->action == PF_DROP) { + dirndx = (dir == PF_OUT); + r->packets[dirndx]++; + r->bytes[dirndx] += pd.tot_len; + if (a != NULL) { + a->packets[dirndx]++; + a->bytes[dirndx] += pd.tot_len; + } + if (s != NULL) { + if (s->nat_rule.ptr != NULL) { + s->nat_rule.ptr->packets[dirndx]++; + s->nat_rule.ptr->bytes[dirndx] += pd.tot_len; + } + if (s->src_node != NULL) { + s->src_node->packets[dirndx]++; + s->src_node->bytes[dirndx] += pd.tot_len; + } + if (s->nat_src_node != NULL) { + s->nat_src_node->packets[dirndx]++; + s->nat_src_node->bytes[dirndx] += pd.tot_len; + } + dirndx = (dir == s->direction) ? 0 : 1; + s->packets[dirndx]++; + s->bytes[dirndx] += pd.tot_len; + } + tr = r; + nr = (s != NULL) ? s->nat_rule.ptr : pd.nat_rule; + if (nr != NULL && r == &V_pf_default_rule) + tr = nr; + if (tr->src.addr.type == PF_ADDR_TABLE) + pfr_update_stats(tr->src.addr.p.tbl, + (s == NULL) ? pd.src : + &s->key[(s->direction == PF_IN)]-> + addr[(s->direction == PF_OUT)], + pd.af, pd.tot_len, dir == PF_OUT, + r->action == PF_PASS, tr->src.neg); + if (tr->dst.addr.type == PF_ADDR_TABLE) + pfr_update_stats(tr->dst.addr.p.tbl, + (s == NULL) ? pd.dst : + &s->key[(s->direction == PF_IN)]-> + addr[(s->direction == PF_IN)], + pd.af, pd.tot_len, dir == PF_OUT, + r->action == PF_PASS, tr->dst.neg); + } + + switch (action) { + case PF_SYNPROXY_DROP: + m_freem(*m0); + case PF_DEFER: + *m0 = NULL; + action = PF_PASS; + break; + default: + /* pf_route() returns unlocked. */ + if (r->rt) { + pf_route(m0, r, dir, kif->pfik_ifp, s, &pd); + return (action); + } + break; + } + if (s) + PF_STATE_UNLOCK(s); + + return (action); +} +#endif /* INET */ + +#ifdef INET6 +int +pf_test6(int dir, struct ifnet *ifp, struct mbuf **m0, struct inpcb *inp) +{ + struct pfi_kif *kif; + u_short action, reason = 0, log = 0; + struct mbuf *m = *m0, *n = NULL; + struct ip6_hdr *h = NULL; + struct pf_rule *a = NULL, *r = &V_pf_default_rule, *tr, *nr; + struct pf_state *s = NULL; + struct pf_ruleset *ruleset = NULL; + struct pf_pdesc pd; + int off, terminal = 0, dirndx, rh_cnt = 0; + + M_ASSERTPKTHDR(m); + + if (!V_pf_status.running) + return (PF_PASS); + + memset(&pd, 0, sizeof(pd)); + pd.pf_mtag = pf_find_mtag(m); + + if (pd.pf_mtag && pd.pf_mtag->flags & PF_TAG_GENERATED) + return (PF_PASS); + + kif = (struct pfi_kif *)ifp->if_pf_kif; + if (kif == NULL) { + DPFPRINTF(PF_DEBUG_URGENT, + ("pf_test6: kif == NULL, if_xname %s\n", ifp->if_xname)); + return (PF_DROP); + } + if (kif->pfik_flags & PFI_IFLAG_SKIP) + return (PF_PASS); + + if (m->m_pkthdr.len < (int)sizeof(*h)) { + action = PF_DROP; + REASON_SET(&reason, PFRES_SHORT); + log = 1; + goto done; + } + + PF_RULES_RLOCK(); + + /* We do IP header normalization and packet reassembly here */ + if (pf_normalize_ip6(m0, dir, kif, &reason, &pd) != PF_PASS) { + action = PF_DROP; + goto done; + } + m = *m0; /* pf_normalize messes with m0 */ + h = mtod(m, struct ip6_hdr *); + +#if 1 + /* + * we do not support jumbogram yet. if we keep going, zero ip6_plen + * will do something bad, so drop the packet for now. + */ + if (htons(h->ip6_plen) == 0) { + action = PF_DROP; + REASON_SET(&reason, PFRES_NORM); /*XXX*/ + goto done; + } +#endif + + pd.src = (struct pf_addr *)&h->ip6_src; + pd.dst = (struct pf_addr *)&h->ip6_dst; + pd.sport = pd.dport = NULL; + pd.ip_sum = NULL; + pd.proto_sum = NULL; + pd.dir = dir; + pd.sidx = (dir == PF_IN) ? 0 : 1; + pd.didx = (dir == PF_IN) ? 1 : 0; + pd.af = AF_INET6; + pd.tos = 0; + pd.tot_len = ntohs(h->ip6_plen) + sizeof(struct ip6_hdr); + + off = ((caddr_t)h - m->m_data) + sizeof(struct ip6_hdr); + pd.proto = h->ip6_nxt; + do { + switch (pd.proto) { + case IPPROTO_FRAGMENT: + action = pf_test_fragment(&r, dir, kif, m, h, + &pd, &a, &ruleset); + if (action == PF_DROP) + REASON_SET(&reason, PFRES_FRAG); + goto done; + case IPPROTO_ROUTING: { + struct ip6_rthdr rthdr; + + if (rh_cnt++) { + DPFPRINTF(PF_DEBUG_MISC, + ("pf: IPv6 more than one rthdr\n")); + action = PF_DROP; + REASON_SET(&reason, PFRES_IPOPTIONS); + log = 1; + goto done; + } + if (!pf_pull_hdr(m, off, &rthdr, sizeof(rthdr), NULL, + &reason, pd.af)) { + DPFPRINTF(PF_DEBUG_MISC, + ("pf: IPv6 short rthdr\n")); + action = PF_DROP; + REASON_SET(&reason, PFRES_SHORT); + log = 1; + goto done; + } + if (rthdr.ip6r_type == IPV6_RTHDR_TYPE_0) { + DPFPRINTF(PF_DEBUG_MISC, + ("pf: IPv6 rthdr0\n")); + action = PF_DROP; + REASON_SET(&reason, PFRES_IPOPTIONS); + log = 1; + goto done; + } + /* FALLTHROUGH */ + } + case IPPROTO_AH: + case IPPROTO_HOPOPTS: + case IPPROTO_DSTOPTS: { + /* get next header and header length */ + struct ip6_ext opt6; + + if (!pf_pull_hdr(m, off, &opt6, sizeof(opt6), + NULL, &reason, pd.af)) { + DPFPRINTF(PF_DEBUG_MISC, + ("pf: IPv6 short opt\n")); + action = PF_DROP; + log = 1; + goto done; + } + if (pd.proto == IPPROTO_AH) + off += (opt6.ip6e_len + 2) * 4; + else + off += (opt6.ip6e_len + 1) * 8; + pd.proto = opt6.ip6e_nxt; + /* goto the next header */ + break; + } + default: + terminal++; + break; + } + } while (!terminal); + + /* if there's no routing header, use unmodified mbuf for checksumming */ + if (!n) + n = m; + + switch (pd.proto) { + + case IPPROTO_TCP: { + struct tcphdr th; + + pd.hdr.tcp = &th; + if (!pf_pull_hdr(m, off, &th, sizeof(th), + &action, &reason, AF_INET6)) { + log = action != PF_PASS; + goto done; + } + pd.p_len = pd.tot_len - off - (th.th_off << 2); + action = pf_normalize_tcp(dir, kif, m, 0, off, h, &pd); + if (action == PF_DROP) + goto done; + action = pf_test_state_tcp(&s, dir, kif, m, off, h, &pd, + &reason); + if (action == PF_PASS) { + if (pfsync_update_state_ptr != NULL) + pfsync_update_state_ptr(s); + r = s->rule.ptr; + a = s->anchor.ptr; + log = s->log; + } else if (s == NULL) + action = pf_test_rule(&r, &s, dir, kif, m, off, &pd, + &a, &ruleset, inp); + break; + } + + case IPPROTO_UDP: { + struct udphdr uh; + + pd.hdr.udp = &uh; + if (!pf_pull_hdr(m, off, &uh, sizeof(uh), + &action, &reason, AF_INET6)) { + log = action != PF_PASS; + goto done; + } + if (uh.uh_dport == 0 || + ntohs(uh.uh_ulen) > m->m_pkthdr.len - off || + ntohs(uh.uh_ulen) < sizeof(struct udphdr)) { + action = PF_DROP; + REASON_SET(&reason, PFRES_SHORT); + goto done; + } + action = pf_test_state_udp(&s, dir, kif, m, off, h, &pd); + if (action == PF_PASS) { + if (pfsync_update_state_ptr != NULL) + pfsync_update_state_ptr(s); + r = s->rule.ptr; + a = s->anchor.ptr; + log = s->log; + } else if (s == NULL) + action = pf_test_rule(&r, &s, dir, kif, m, off, &pd, + &a, &ruleset, inp); + break; + } + + case IPPROTO_ICMP: { + action = PF_DROP; + DPFPRINTF(PF_DEBUG_MISC, + ("pf: dropping IPv6 packet with ICMPv4 payload\n")); + goto done; + } + + case IPPROTO_ICMPV6: { + struct icmp6_hdr ih; + + pd.hdr.icmp6 = &ih; + if (!pf_pull_hdr(m, off, &ih, sizeof(ih), + &action, &reason, AF_INET6)) { + log = action != PF_PASS; + goto done; + } + action = pf_test_state_icmp(&s, dir, kif, + m, off, h, &pd, &reason); + if (action == PF_PASS) { + if (pfsync_update_state_ptr != NULL) + pfsync_update_state_ptr(s); + r = s->rule.ptr; + a = s->anchor.ptr; + log = s->log; + } else if (s == NULL) + action = pf_test_rule(&r, &s, dir, kif, m, off, &pd, + &a, &ruleset, inp); + break; + } + + default: + action = pf_test_state_other(&s, dir, kif, m, &pd); + if (action == PF_PASS) { + if (pfsync_update_state_ptr != NULL) + pfsync_update_state_ptr(s); + r = s->rule.ptr; + a = s->anchor.ptr; + log = s->log; + } else if (s == NULL) + action = pf_test_rule(&r, &s, dir, kif, m, off, &pd, + &a, &ruleset, inp); + break; + } + +done: + PF_RULES_RUNLOCK(); + if (n != m) { + m_freem(n); + n = NULL; + } + + /* handle dangerous IPv6 extension headers. */ + if (action == PF_PASS && rh_cnt && + !((s && s->state_flags & PFSTATE_ALLOWOPTS) || r->allow_opts)) { + action = PF_DROP; + REASON_SET(&reason, PFRES_IPOPTIONS); + log = 1; + DPFPRINTF(PF_DEBUG_MISC, + ("pf: dropping packet with dangerous v6 headers\n")); + } + + if (s && s->tag > 0 && pf_tag_packet(m, &pd, s->tag)) { + action = PF_DROP; + REASON_SET(&reason, PFRES_MEMORY); + } + if (r->rtableid >= 0) + M_SETFIB(m, r->rtableid); + +#ifdef ALTQ + if (action == PF_PASS && r->qid) { + if (pd.pf_mtag == NULL && + ((pd.pf_mtag = pf_get_mtag(m)) == NULL)) { + action = PF_DROP; + REASON_SET(&reason, PFRES_MEMORY); + } + if (pd.tos & IPTOS_LOWDELAY) + pd.pf_mtag->qid = r->pqid; + else + pd.pf_mtag->qid = r->qid; + /* add hints for ecn */ + pd.pf_mtag->hdr = h; + } +#endif /* ALTQ */ + + if (dir == PF_IN && action == PF_PASS && (pd.proto == IPPROTO_TCP || + pd.proto == IPPROTO_UDP) && s != NULL && s->nat_rule.ptr != NULL && + (s->nat_rule.ptr->action == PF_RDR || + s->nat_rule.ptr->action == PF_BINAT) && + IN6_IS_ADDR_LOOPBACK(&pd.dst->v6)) + m->m_flags |= M_SKIP_FIREWALL; + + /* XXX: Anybody working on it?! */ + if (r->divert.port) + printf("pf: divert(9) is not supported for IPv6\n"); + + if (log) { + struct pf_rule *lr; + + if (s != NULL && s->nat_rule.ptr != NULL && + s->nat_rule.ptr->log & PF_LOG_ALL) + lr = s->nat_rule.ptr; + else + lr = r; + PFLOG_PACKET(kif, m, AF_INET6, dir, reason, lr, a, ruleset, + &pd, (s == NULL)); + } + + kif->pfik_bytes[1][dir == PF_OUT][action != PF_PASS] += pd.tot_len; + kif->pfik_packets[1][dir == PF_OUT][action != PF_PASS]++; + + if (action == PF_PASS || r->action == PF_DROP) { + dirndx = (dir == PF_OUT); + r->packets[dirndx]++; + r->bytes[dirndx] += pd.tot_len; + if (a != NULL) { + a->packets[dirndx]++; + a->bytes[dirndx] += pd.tot_len; + } + if (s != NULL) { + if (s->nat_rule.ptr != NULL) { + s->nat_rule.ptr->packets[dirndx]++; + s->nat_rule.ptr->bytes[dirndx] += pd.tot_len; + } + if (s->src_node != NULL) { + s->src_node->packets[dirndx]++; + s->src_node->bytes[dirndx] += pd.tot_len; + } + if (s->nat_src_node != NULL) { + s->nat_src_node->packets[dirndx]++; + s->nat_src_node->bytes[dirndx] += pd.tot_len; + } + dirndx = (dir == s->direction) ? 0 : 1; + s->packets[dirndx]++; + s->bytes[dirndx] += pd.tot_len; + } + tr = r; + nr = (s != NULL) ? s->nat_rule.ptr : pd.nat_rule; + if (nr != NULL && r == &V_pf_default_rule) + tr = nr; + if (tr->src.addr.type == PF_ADDR_TABLE) + pfr_update_stats(tr->src.addr.p.tbl, + (s == NULL) ? pd.src : + &s->key[(s->direction == PF_IN)]->addr[0], + pd.af, pd.tot_len, dir == PF_OUT, + r->action == PF_PASS, tr->src.neg); + if (tr->dst.addr.type == PF_ADDR_TABLE) + pfr_update_stats(tr->dst.addr.p.tbl, + (s == NULL) ? pd.dst : + &s->key[(s->direction == PF_IN)]->addr[1], + pd.af, pd.tot_len, dir == PF_OUT, + r->action == PF_PASS, tr->dst.neg); + } + + switch (action) { + case PF_SYNPROXY_DROP: + m_freem(*m0); + case PF_DEFER: + *m0 = NULL; + action = PF_PASS; + break; + default: + /* pf_route6() returns unlocked. */ + if (r->rt) { + pf_route6(m0, r, dir, kif->pfik_ifp, s, &pd); + return (action); + } + break; + } + + if (s) + PF_STATE_UNLOCK(s); + + return (action); +} +#endif /* INET6 */ |