/*- * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2001 Daniel Hartmeier * Copyright (c) 2002 - 2008 Henning Brauer * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * - Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials provided * with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * Effort sponsored in part by the Defense Advanced Research Projects * Agency (DARPA) and Air Force Research Laboratory, Air Force * Materiel Command, USAF, under agreement number F30602-01-2-0537. * * $OpenBSD: pf_lb.c,v 1.2 2009/02/12 02:13:15 sthen Exp $ */ #include #include "opt_pf.h" #include "opt_inet.h" #include "opt_inet6.h" #include #include #include #include #include #include #include #include #include #include #include #ifdef INET #include #endif /* INET */ #ifdef INET6 #include #endif /* INET6 */ /* * Limit the amount of work we do to find a free source port for redirects that * introduce a state conflict. */ #define V_pf_rdr_srcport_rewrite_tries VNET(pf_rdr_srcport_rewrite_tries) VNET_DEFINE_STATIC(int, pf_rdr_srcport_rewrite_tries) = 16; static uint64_t pf_hash(struct pf_addr *, struct pf_addr *, struct pf_poolhashkey *, sa_family_t); struct pf_krule *pf_match_translation(int, struct pf_test_ctx *); static enum pf_test_status pf_step_into_translation_anchor(int, struct pf_test_ctx *, struct pf_krule *); static int pf_get_sport(struct pf_pdesc *, struct pf_krule *, struct pf_addr *, uint16_t *, uint16_t, uint16_t, struct pf_kpool *, struct pf_udp_mapping **, pf_sn_types_t); static bool pf_islinklocal(const sa_family_t, const struct pf_addr *); static uint64_t pf_hash(struct pf_addr *inaddr, struct pf_addr *hash, struct pf_poolhashkey *key, sa_family_t af) { SIPHASH_CTX ctx; #ifdef INET6 union { uint64_t hash64; uint32_t hash32[2]; } h; #endif /* INET6 */ uint64_t res = 0; _Static_assert(sizeof(*key) >= SIPHASH_KEY_LENGTH, ""); switch (af) { #ifdef INET case AF_INET: res = SipHash24(&ctx, (const uint8_t *)key, &inaddr->addr32[0], sizeof(inaddr->addr32[0])); hash->addr32[0] = res; break; #endif /* INET */ #ifdef INET6 case AF_INET6: res = SipHash24(&ctx, (const uint8_t *)key, &inaddr->addr32[0], 4 * sizeof(inaddr->addr32[0])); h.hash64 = res; hash->addr32[0] = h.hash32[0]; hash->addr32[1] = h.hash32[1]; /* * siphash isn't big enough, but flipping it around is * good enough here. */ hash->addr32[2] = ~h.hash32[1]; hash->addr32[3] = ~h.hash32[0]; break; #endif /* INET6 */ default: unhandled_af(af); } return (res); } #define PF_TEST_ATTRIB(t, a) \ if (t) { \ r = a; \ continue; \ } else do { \ } while (0) static enum pf_test_status pf_match_translation_rule(int rs_num, struct pf_test_ctx *ctx, struct pf_kruleset *ruleset) { struct pf_krule *r; struct pf_pdesc *pd = ctx->pd; int rtableid = -1; r = TAILQ_FIRST(ruleset->rules[rs_num].active.ptr); while (r != NULL) { struct pf_rule_addr *src = NULL, *dst = NULL; struct pf_addr_wrap *xdst = NULL; if (r->action == PF_BINAT && pd->dir == PF_IN) { src = &r->dst; if (r->rdr.cur != NULL) xdst = &r->rdr.cur->addr; } else { src = &r->src; dst = &r->dst; } pf_counter_u64_add(&r->evaluations, 1); PF_TEST_ATTRIB(pfi_kkif_match(r->kif, pd->kif) == r->ifnot, r->skip[PF_SKIP_IFP]); PF_TEST_ATTRIB(r->direction && r->direction != pd->dir, r->skip[PF_SKIP_DIR]); PF_TEST_ATTRIB(r->af && r->af != pd->af, r->skip[PF_SKIP_AF]); PF_TEST_ATTRIB(r->proto && r->proto != pd->proto, r->skip[PF_SKIP_PROTO]); PF_TEST_ATTRIB(PF_MISMATCHAW(&src->addr, &pd->nsaddr, pd->af, src->neg, pd->kif, M_GETFIB(pd->m)), r->skip[src == &r->src ? PF_SKIP_SRC_ADDR : PF_SKIP_DST_ADDR]); PF_TEST_ATTRIB(src->port_op && !pf_match_port(src->port_op, src->port[0], src->port[1], pd->nsport), r->skip[src == &r->src ? PF_SKIP_SRC_PORT : PF_SKIP_DST_PORT]); PF_TEST_ATTRIB(dst != NULL && PF_MISMATCHAW(&dst->addr, &pd->ndaddr, pd->af, dst->neg, NULL, M_GETFIB(pd->m)), r->skip[PF_SKIP_DST_ADDR]); PF_TEST_ATTRIB(xdst != NULL && PF_MISMATCHAW(xdst, &pd->ndaddr, pd->af, 0, NULL, M_GETFIB(pd->m)), TAILQ_NEXT(r, entries)); PF_TEST_ATTRIB(dst != NULL && dst->port_op && !pf_match_port(dst->port_op, dst->port[0], dst->port[1], pd->ndport), r->skip[PF_SKIP_DST_PORT]); PF_TEST_ATTRIB(r->match_tag && !pf_match_tag(pd->m, r, &ctx->tag, pd->pf_mtag ? pd->pf_mtag->tag : 0), TAILQ_NEXT(r, entries)); PF_TEST_ATTRIB(r->os_fingerprint != PF_OSFP_ANY && (pd->proto != IPPROTO_TCP || !pf_osfp_match(pf_osfp_fingerprint(pd, &pd->hdr.tcp), r->os_fingerprint)), TAILQ_NEXT(r, entries)); if (r->tag) ctx->tag = r->tag; if (r->rtableid >= 0) rtableid = r->rtableid; if (r->anchor == NULL) { if (r->action == PF_NONAT || r->action == PF_NORDR || r->action == PF_NOBINAT) { *ctx->rm = NULL; } else { /* * found matching r */ ctx->tr = r; /* * anchor, with ruleset, where r belongs to */ *ctx->am = ctx->a; /* * ruleset where r belongs to */ *ctx->rsm = ruleset; /* * ruleset, where anchor belongs to. */ ctx->arsm = ctx->aruleset; } break; } else { ctx->a = r; /* remember anchor */ ctx->aruleset = ruleset; /* and its ruleset */ if (pf_step_into_translation_anchor(rs_num, ctx, r) != PF_TEST_OK) { break; } } r = TAILQ_NEXT(r, entries); } if (ctx->tag > 0 && pf_tag_packet(pd, ctx->tag)) return (PF_TEST_FAIL); if (rtableid >= 0) M_SETFIB(pd->m, rtableid); return (PF_TEST_OK); } static enum pf_test_status pf_step_into_translation_anchor(int rs_num, struct pf_test_ctx *ctx, struct pf_krule *r) { enum pf_test_status rv; PF_RULES_RASSERT(); if (ctx->depth >= PF_ANCHOR_STACK_MAX) { printf("%s: anchor stack overflow on %s\n", __func__, r->anchor->name); return (PF_TEST_FAIL); } ctx->depth++; if (r->anchor_wildcard) { struct pf_kanchor *child; rv = PF_TEST_OK; RB_FOREACH(child, pf_kanchor_node, &r->anchor->children) { rv = pf_match_translation_rule(rs_num, ctx, &child->ruleset); if ((rv == PF_TEST_QUICK) || (rv == PF_TEST_FAIL)) { /* * we either hit a rule qith quick action * (more likely), or hit some runtime * error (e.g. pool_get() faillure). */ break; } } } else { rv = pf_match_translation_rule(rs_num, ctx, &r->anchor->ruleset); } ctx->depth--; return (rv); } struct pf_krule * pf_match_translation(int rs_num, struct pf_test_ctx *ctx) { enum pf_test_status rv; MPASS(ctx->depth == 0); rv = pf_match_translation_rule(rs_num, ctx, &pf_main_ruleset); MPASS(ctx->depth == 0); if (rv != PF_TEST_OK) return (NULL); return (ctx->tr); } static int pf_get_sport(struct pf_pdesc *pd, struct pf_krule *r, struct pf_addr *naddr, uint16_t *nport, uint16_t low, uint16_t high, struct pf_kpool *rpool, struct pf_udp_mapping **udp_mapping, pf_sn_types_t sn_type) { struct pf_state_key_cmp key; struct pf_addr init_addr; int dir = (pd->dir == PF_IN) ? PF_OUT : PF_IN; int sidx = pd->sidx; int didx = pd->didx; bzero(&init_addr, sizeof(init_addr)); MPASS(udp_mapping == NULL || *udp_mapping == NULL); /* * If we are UDP and have an existing mapping we can get source port * from the mapping. In this case we have to look up the src_node as * pf_map_addr would. */ if (pd->proto == IPPROTO_UDP && (rpool->opts & PF_POOL_ENDPI)) { struct pf_udp_endpoint_cmp udp_source; bzero(&udp_source, sizeof(udp_source)); udp_source.af = pd->af; pf_addrcpy(&udp_source.addr, &pd->nsaddr, pd->af); udp_source.port = pd->nsport; if (udp_mapping) { struct pf_ksrc_node *sn = NULL; struct pf_srchash *sh = NULL; *udp_mapping = pf_udp_mapping_find(&udp_source); if (*udp_mapping) { pf_addrcpy(naddr, &(*udp_mapping)->endpoints[1].addr, pd->af); *nport = (*udp_mapping)->endpoints[1].port; /* * Try to find a src_node as per pf_map_addr(). * XXX: Why? This code seems to do nothing. */ if (rpool->opts & PF_POOL_STICKYADDR && (rpool->opts & PF_POOL_TYPEMASK) != PF_POOL_NONE) sn = pf_find_src_node(&pd->nsaddr, r, pd->af, &sh, sn_type, false); if (sn != NULL) PF_SRC_NODE_UNLOCK(sn); return (0); } else { *udp_mapping = pf_udp_mapping_create(pd->af, &pd->nsaddr, pd->nsport, &init_addr, 0); if (*udp_mapping == NULL) return (1); } } } if (pf_map_addr_sn(pd->naf, r, &pd->nsaddr, naddr, &(pd->naf), NULL, &init_addr, rpool, sn_type)) goto failed; if (pd->proto == IPPROTO_ICMP) { if (pd->ndport == htons(ICMP_ECHO)) { low = 1; high = 65535; } else { MPASS(udp_mapping == NULL || *udp_mapping == NULL); return (0); /* Don't try to modify non-echo ICMP */ } } #ifdef INET6 if (pd->proto == IPPROTO_ICMPV6) { if (pd->ndport == htons(ICMP6_ECHO_REQUEST)) { low = 1; high = 65535; } else { MPASS(udp_mapping == NULL || *udp_mapping == NULL); return (0); /* Don't try to modify non-echo ICMP */ } } #endif /* INET6 */ bzero(&key, sizeof(key)); key.af = pd->naf; key.proto = pd->proto; do { pf_addrcpy(&key.addr[didx], &pd->ndaddr, key.af); pf_addrcpy(&key.addr[sidx], naddr, key.af); key.port[didx] = pd->ndport; if (udp_mapping && *udp_mapping) pf_addrcpy(&(*udp_mapping)->endpoints[1].addr, naddr, pd->af); /* * port search; start random, step; * similar 2 portloop in in_pcbbind */ if (pd->proto == IPPROTO_SCTP) { key.port[sidx] = pd->nsport; MPASS(udp_mapping == NULL || *udp_mapping == NULL); if (!pf_find_state_all_exists(&key, dir)) { *nport = pd->nsport; return (0); } else { return (1); /* Fail mapping. */ } } else if (!(pd->proto == IPPROTO_TCP || pd->proto == IPPROTO_UDP || pd->proto == IPPROTO_ICMP) || (low == 0 && high == 0)) { /* * XXX bug: icmp states don't use the id on both sides. * (traceroute -I through nat) */ key.port[sidx] = pd->nsport; if (!pf_find_state_all_exists(&key, dir)) { if (udp_mapping && *udp_mapping != NULL) { (*udp_mapping)->endpoints[1].port = pd->nsport; if (pf_udp_mapping_insert(*udp_mapping) == 0) { *nport = pd->nsport; return (0); } } else { MPASS(udp_mapping == NULL || *udp_mapping == NULL); *nport = pd->nsport; return (0); } } } else if (low == high) { key.port[sidx] = htons(low); if (!pf_find_state_all_exists(&key, dir)) { if (udp_mapping && *udp_mapping != NULL) { (*udp_mapping)->endpoints[1].port = htons(low); if (pf_udp_mapping_insert(*udp_mapping) == 0) { *nport = htons(low); return (0); } } else { MPASS(udp_mapping == NULL || *udp_mapping == NULL); *nport = htons(low); return (0); } } } else { uint32_t tmp; uint16_t cut; if (low > high) { tmp = low; low = high; high = tmp; } /* low < high */ cut = arc4random() % (1 + high - low) + low; /* low <= cut <= high */ for (tmp = cut; tmp <= high && tmp <= 0xffff; ++tmp) { if (udp_mapping && *udp_mapping != NULL) { (*udp_mapping)->endpoints[sidx].port = htons(tmp); if (pf_udp_mapping_insert(*udp_mapping) == 0) { *nport = htons(tmp); return (0); } } else { key.port[sidx] = htons(tmp); if (!pf_find_state_all_exists(&key, dir)) { *nport = htons(tmp); MPASS(udp_mapping == NULL || *udp_mapping == NULL); return (0); } } } tmp = cut; for (tmp -= 1; tmp >= low && tmp <= 0xffff; --tmp) { if (pd->proto == IPPROTO_UDP && (rpool->opts & PF_POOL_ENDPI && udp_mapping != NULL)) { (*udp_mapping)->endpoints[1].port = htons(tmp); if (pf_udp_mapping_insert(*udp_mapping) == 0) { *nport = htons(tmp); return (0); } } else { key.port[sidx] = htons(tmp); if (!pf_find_state_all_exists(&key, dir)) { MPASS(udp_mapping == NULL || *udp_mapping == NULL); *nport = htons(tmp); return (0); } } } } switch (rpool->opts & PF_POOL_TYPEMASK) { case PF_POOL_RANDOM: case PF_POOL_ROUNDROBIN: /* * pick a different source address since we're out * of free port choices for the current one. */ if (pf_map_addr_sn(pd->naf, r, &pd->nsaddr, naddr, &(pd->naf), NULL, &init_addr, rpool, sn_type)) goto failed; break; case PF_POOL_NONE: case PF_POOL_SRCHASH: case PF_POOL_BITMASK: default: goto failed; } } while (! PF_AEQ(&init_addr, naddr, pd->naf) ); failed: if (udp_mapping) { uma_zfree(V_pf_udp_mapping_z, *udp_mapping); *udp_mapping = NULL; } return (1); /* none available */ } static bool pf_islinklocal(const sa_family_t af, const struct pf_addr *addr) { if (af == AF_INET6 && IN6_IS_ADDR_LINKLOCAL(&addr->v6)) return (true); return (false); } static int pf_get_mape_sport(struct pf_pdesc *pd, struct pf_krule *r, struct pf_addr *naddr, uint16_t *nport, struct pf_udp_mapping **udp_mapping, struct pf_kpool *rpool) { uint16_t psmask, low, highmask; uint16_t i, ahigh, cut; int ashift, psidshift; ashift = 16 - rpool->mape.offset; psidshift = ashift - rpool->mape.psidlen; psmask = rpool->mape.psid & ((1U << rpool->mape.psidlen) - 1); psmask = psmask << psidshift; highmask = (1U << psidshift) - 1; ahigh = (1U << rpool->mape.offset) - 1; cut = arc4random() & ahigh; if (cut == 0) cut = 1; for (i = cut; i <= ahigh; i++) { low = (i << ashift) | psmask; if (!pf_get_sport(pd, r, naddr, nport, low, low | highmask, rpool, udp_mapping, PF_SN_NAT)) return (0); } for (i = cut - 1; i > 0; i--) { low = (i << ashift) | psmask; if (!pf_get_sport(pd, r, naddr, nport, low, low | highmask, rpool, udp_mapping, PF_SN_NAT)) return (0); } return (1); } u_short pf_map_addr(sa_family_t saf, struct pf_krule *r, struct pf_addr *saddr, struct pf_addr *naddr, struct pfi_kkif **nkif, sa_family_t *naf, struct pf_addr *init_addr, struct pf_kpool *rpool) { u_short reason = PFRES_MATCH; struct pf_addr *raddr = NULL, *rmask = NULL; struct pfr_ktable *kt; uint64_t hashidx; int cnt; sa_family_t wanted_af; u_int8_t pool_type; bool prefer_ipv6_nexthop = rpool->opts & PF_POOL_IPV6NH; KASSERT(saf != 0, ("%s: saf == 0", __func__)); KASSERT(naf != NULL, ("%s: naf = NULL", __func__)); KASSERT((*naf) != 0, ("%s: *naf = 0", __func__)); /* * Given (*naf) is a hint about AF of the forwarded packet. * It might be changed if prefer_ipv6_nexthop is enabled and * the combination of nexthop AF and packet AF allows for it. */ wanted_af = (*naf); mtx_lock(&rpool->mtx); /* Find the route using chosen algorithm. Store the found route in src_node if it was given or found. */ if (rpool->cur->addr.type == PF_ADDR_NOROUTE) { reason = PFRES_MAPFAILED; goto done_pool_mtx; } if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) { switch (wanted_af) { #ifdef INET case AF_INET: if (rpool->cur->addr.p.dyn->pfid_acnt4 < 1 && !PF_POOL_DYNTYPE(rpool->opts)) { reason = PFRES_MAPFAILED; goto done_pool_mtx; } raddr = &rpool->cur->addr.p.dyn->pfid_addr4; rmask = &rpool->cur->addr.p.dyn->pfid_mask4; break; #endif /* INET */ #ifdef INET6 case AF_INET6: if (rpool->cur->addr.p.dyn->pfid_acnt6 < 1 && !PF_POOL_DYNTYPE(rpool->opts)) { reason = PFRES_MAPFAILED; goto done_pool_mtx; } raddr = &rpool->cur->addr.p.dyn->pfid_addr6; rmask = &rpool->cur->addr.p.dyn->pfid_mask6; break; #endif /* INET6 */ default: unhandled_af(wanted_af); } } else if (rpool->cur->addr.type == PF_ADDR_TABLE) { if (!PF_POOL_DYNTYPE(rpool->opts)) { reason = PFRES_MAPFAILED; goto done_pool_mtx; /* unsupported */ } } else { raddr = &rpool->cur->addr.v.a.addr; rmask = &rpool->cur->addr.v.a.mask; } /* * For pools with a single host with the prefer-ipv6-nexthop option * we can return pool address of any AF, unless the forwarded packet * is IPv6, then we can return only if pool address is IPv6. * For non-prefer-ipv6-nexthop we can return pool address only * of wanted AF, unless the pool address'es AF is unknown, which * happens in case old ioctls have been used to set up the pool. * * Round-robin pools have their own logic for retrying next addresses. */ pool_type = rpool->opts & PF_POOL_TYPEMASK; if (pool_type == PF_POOL_NONE || pool_type == PF_POOL_BITMASK || ((pool_type == PF_POOL_RANDOM || pool_type == PF_POOL_SRCHASH) && rpool->cur->addr.type != PF_ADDR_TABLE && rpool->cur->addr.type != PF_ADDR_DYNIFTL)) { if (prefer_ipv6_nexthop) { if (rpool->cur->af == AF_INET && (*naf) == AF_INET6) { reason = PFRES_MAPFAILED; goto done_pool_mtx; } wanted_af = rpool->cur->af; } else { if (rpool->cur->af != 0 && rpool->cur->af != (*naf)) { reason = PFRES_MAPFAILED; goto done_pool_mtx; } } } switch (pool_type) { case PF_POOL_NONE: pf_addrcpy(naddr, raddr, wanted_af); break; case PF_POOL_BITMASK: pf_poolmask(naddr, raddr, rmask, saddr, wanted_af); break; case PF_POOL_RANDOM: if (rpool->cur->addr.type == PF_ADDR_TABLE || rpool->cur->addr.type == PF_ADDR_DYNIFTL) { if (rpool->cur->addr.type == PF_ADDR_TABLE) kt = rpool->cur->addr.p.tbl; else kt = rpool->cur->addr.p.dyn->pfid_kt; kt = pfr_ktable_select_active(kt); if (kt == NULL) { reason = PFRES_MAPFAILED; goto done_pool_mtx; /* unsupported */ } cnt = kt->pfrkt_cnt; if (cnt == 0) rpool->tblidx = 0; else rpool->tblidx = (int)arc4random_uniform(cnt); memset(&rpool->counter, 0, sizeof(rpool->counter)); if (prefer_ipv6_nexthop) wanted_af = AF_INET6; retry_other_af_random: if (pfr_pool_get(kt, &rpool->tblidx, &rpool->counter, wanted_af, pf_islinklocal, false)) { /* Retry with IPv4 nexthop for IPv4 traffic */ if (prefer_ipv6_nexthop && wanted_af == AF_INET6 && (*naf) == AF_INET) { wanted_af = AF_INET; goto retry_other_af_random; } else { /* no hosts in wanted AF */ reason = PFRES_MAPFAILED; goto done_pool_mtx; } } pf_addrcpy(naddr, &rpool->counter, wanted_af); } else if (init_addr != NULL && PF_AZERO(init_addr, wanted_af)) { switch (wanted_af) { #ifdef INET case AF_INET: rpool->counter.addr32[0] = arc4random(); break; #endif /* INET */ #ifdef INET6 case AF_INET6: if (rmask->addr32[3] != 0xffffffff) rpool->counter.addr32[3] = arc4random(); else break; if (rmask->addr32[2] != 0xffffffff) rpool->counter.addr32[2] = arc4random(); else break; if (rmask->addr32[1] != 0xffffffff) rpool->counter.addr32[1] = arc4random(); else break; if (rmask->addr32[0] != 0xffffffff) rpool->counter.addr32[0] = arc4random(); break; #endif /* INET6 */ } pf_poolmask(naddr, raddr, rmask, &rpool->counter, wanted_af); pf_addrcpy(init_addr, naddr, wanted_af); } else { pf_addr_inc(&rpool->counter, wanted_af); pf_poolmask(naddr, raddr, rmask, &rpool->counter, wanted_af); } break; case PF_POOL_SRCHASH: { unsigned char hash[16]; hashidx = pf_hash(saddr, (struct pf_addr *)&hash, &rpool->key, wanted_af); if (rpool->cur->addr.type == PF_ADDR_TABLE || rpool->cur->addr.type == PF_ADDR_DYNIFTL) { if (rpool->cur->addr.type == PF_ADDR_TABLE) kt = rpool->cur->addr.p.tbl; else kt = rpool->cur->addr.p.dyn->pfid_kt; kt = pfr_ktable_select_active(kt); if (kt == NULL) { reason = PFRES_MAPFAILED; goto done_pool_mtx; /* unsupported */ } cnt = kt->pfrkt_cnt; if (cnt == 0) rpool->tblidx = 0; else rpool->tblidx = (int)(hashidx % cnt); memset(&rpool->counter, 0, sizeof(rpool->counter)); if (prefer_ipv6_nexthop) wanted_af = AF_INET6; retry_other_af_srchash: if (pfr_pool_get(kt, &rpool->tblidx, &rpool->counter, wanted_af, pf_islinklocal, false)) { /* Retry with IPv4 nexthop for IPv4 traffic */ if (prefer_ipv6_nexthop && wanted_af == AF_INET6 && (*naf) == AF_INET) { wanted_af = AF_INET; goto retry_other_af_srchash; } else { /* no hosts in wanted AF */ reason = PFRES_MAPFAILED; goto done_pool_mtx; } } pf_addrcpy(naddr, &rpool->counter, wanted_af); } else { pf_poolmask(naddr, raddr, rmask, (struct pf_addr *)&hash, wanted_af); } break; } case PF_POOL_ROUNDROBIN: { struct pf_kpooladdr *acur = rpool->cur; retry_other_af_rr: if (prefer_ipv6_nexthop) wanted_af = rpool->ipv6_nexthop_af; if (rpool->cur->addr.type == PF_ADDR_TABLE) { if (!pfr_pool_get(rpool->cur->addr.p.tbl, &rpool->tblidx, &rpool->counter, wanted_af, NULL, true)) goto get_addr; } else if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) { if (!pfr_pool_get(rpool->cur->addr.p.dyn->pfid_kt, &rpool->tblidx, &rpool->counter, wanted_af, pf_islinklocal, true)) goto get_addr; } else if (rpool->cur->af == wanted_af && pf_match_addr(0, raddr, rmask, &rpool->counter, wanted_af)) goto get_addr; if (prefer_ipv6_nexthop && (*naf) == AF_INET && wanted_af == AF_INET6) { /* Reset table index when changing wanted AF. */ rpool->tblidx = -1; rpool->ipv6_nexthop_af = AF_INET; goto retry_other_af_rr; } try_next: /* Reset prefer-ipv6-nexthop search to IPv6 when iterating pools. */ rpool->ipv6_nexthop_af = AF_INET6; if (TAILQ_NEXT(rpool->cur, entries) == NULL) rpool->cur = TAILQ_FIRST(&rpool->list); else rpool->cur = TAILQ_NEXT(rpool->cur, entries); try_next_ipv6_nexthop_rr: /* Reset table index when iterating pools or changing wanted AF. */ rpool->tblidx = -1; if (prefer_ipv6_nexthop) wanted_af = rpool->ipv6_nexthop_af; if (rpool->cur->addr.type == PF_ADDR_TABLE) { if (!pfr_pool_get(rpool->cur->addr.p.tbl, &rpool->tblidx, &rpool->counter, wanted_af, NULL, true)) goto get_addr; } else if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) { if (!pfr_pool_get(rpool->cur->addr.p.dyn->pfid_kt, &rpool->tblidx, &rpool->counter, wanted_af, pf_islinklocal, true)) goto get_addr; } else { if (rpool->cur->af == wanted_af) { raddr = &rpool->cur->addr.v.a.addr; rmask = &rpool->cur->addr.v.a.mask; pf_addrcpy(&rpool->counter, raddr, wanted_af); goto get_addr; } } if (prefer_ipv6_nexthop && (*naf) == AF_INET && wanted_af == AF_INET6) { rpool->ipv6_nexthop_af = AF_INET; goto try_next_ipv6_nexthop_rr; } if (rpool->cur != acur) goto try_next; reason = PFRES_MAPFAILED; goto done_pool_mtx; get_addr: pf_addrcpy(naddr, &rpool->counter, wanted_af); if (init_addr != NULL && PF_AZERO(init_addr, wanted_af)) pf_addrcpy(init_addr, naddr, wanted_af); pf_addr_inc(&rpool->counter, wanted_af); break; } } if (wanted_af == 0) { reason = PFRES_MAPFAILED; goto done_pool_mtx; } if (nkif) *nkif = rpool->cur->kif; (*naf) = wanted_af; done_pool_mtx: mtx_unlock(&rpool->mtx); return (reason); } u_short pf_map_addr_sn(sa_family_t saf, struct pf_krule *r, struct pf_addr *saddr, struct pf_addr *naddr, sa_family_t *naf, struct pfi_kkif **nkif, struct pf_addr *init_addr, struct pf_kpool *rpool, pf_sn_types_t sn_type) { struct pf_ksrc_node *sn = NULL; struct pf_srchash *sh = NULL; u_short reason = 0; /* * If this is a sticky-address rule, try to find an existing src_node. */ if (rpool->opts & PF_POOL_STICKYADDR && (rpool->opts & PF_POOL_TYPEMASK) != PF_POOL_NONE) sn = pf_find_src_node(saddr, r, saf, &sh, sn_type, false); if (sn != NULL) { PF_SRC_NODE_LOCK_ASSERT(sn); (*naf) = sn->raf; /* If the supplied address is the same as the current one we've * been asked before, so tell the caller that there's no other * address to be had. */ if (PF_AEQ(naddr, &(sn->raddr), *naf)) { printf("%s: no more addresses\n", __func__); reason = PFRES_MAPFAILED; goto done; } pf_addrcpy(naddr, &(sn->raddr), *naf); if (nkif) *nkif = sn->rkif; if (V_pf_status.debug >= PF_DEBUG_NOISY) { printf("%s: src tracking maps ", __func__); pf_print_host(saddr, 0, saf); printf(" to "); pf_print_host(naddr, 0, *naf); if (nkif) printf("@%s", (*nkif)->pfik_name); printf("\n"); } goto done; } /* * Source node has not been found. Find a new address and store it * in variables given by the caller. */ if ((reason = pf_map_addr(saf, r, saddr, naddr, nkif, naf, init_addr, rpool)) != 0) { if (V_pf_status.debug >= PF_DEBUG_MISC) printf("%s: pf_map_addr has failed\n", __func__); goto done; } if (V_pf_status.debug >= PF_DEBUG_NOISY && (rpool->opts & PF_POOL_TYPEMASK) != PF_POOL_NONE) { printf("%s: selected address ", __func__); pf_print_host(naddr, 0, *naf); if (nkif) printf("@%s", (*nkif)->pfik_name); printf("\n"); } done: if (sn != NULL) PF_SRC_NODE_UNLOCK(sn); return (reason); } u_short pf_get_translation(struct pf_test_ctx *ctx) { struct pf_krule *r = NULL; u_short transerror; PF_RULES_RASSERT(); KASSERT(ctx->sk == NULL, ("*skp not NULL")); KASSERT(ctx->nk == NULL, ("*nkp not NULL")); ctx->nr = NULL; if (ctx->pd->dir == PF_OUT) { r = pf_match_translation(PF_RULESET_BINAT, ctx); if (r == NULL) r = pf_match_translation(PF_RULESET_NAT, ctx); } else { r = pf_match_translation(PF_RULESET_RDR, ctx); if (r == NULL) r = pf_match_translation(PF_RULESET_BINAT, ctx); } if (r == NULL) return (PFRES_MAX); switch (r->action) { case PF_NONAT: case PF_NOBINAT: case PF_NORDR: return (PFRES_MAX); } transerror = pf_get_transaddr(ctx, r, r->action, &(r->rdr)); if (transerror == PFRES_MATCH) ctx->nr = r; return (transerror); } u_short pf_get_transaddr(struct pf_test_ctx *ctx, struct pf_krule *r, uint8_t nat_action, struct pf_kpool *rpool) { struct pf_pdesc *pd = ctx->pd; struct pf_addr *naddr; int idx; uint16_t *nportp; uint16_t low, high; u_short reason; PF_RULES_RASSERT(); KASSERT(r != NULL, ("r is NULL")); KASSERT(!(r->rule_flag & PFRULE_AFTO), ("AFTO rule")); if (ctx->sk == NULL && ctx->nk == NULL) { if (pf_state_key_setup(pd, pd->nsport, pd->ndport, &ctx->sk, &ctx->nk)) return (PFRES_MEMORY); } switch (nat_action) { case PF_NAT: idx = pd->sidx; break; case PF_BINAT: idx = 1; break; case PF_RDR: idx = pd->didx; break; } naddr = &ctx->nk->addr[idx]; nportp = &ctx->nk->port[idx]; switch (nat_action) { case PF_NAT: if (pd->proto == IPPROTO_ICMP) { low = 1; high = 65535; } else { low = rpool->proxy_port[0]; high = rpool->proxy_port[1]; } if (rpool->mape.offset > 0) { if (pf_get_mape_sport(pd, r, naddr, nportp, &ctx->udp_mapping, rpool)) { DPFPRINTF(PF_DEBUG_MISC, "pf: MAP-E port allocation (%u/%u/%u)" " failed", rpool->mape.offset, rpool->mape.psidlen, rpool->mape.psid); reason = PFRES_MAPFAILED; goto notrans; } } else if (pf_get_sport(pd, r, naddr, nportp, low, high, rpool, &ctx->udp_mapping, PF_SN_NAT)) { DPFPRINTF(PF_DEBUG_MISC, "pf: NAT proxy port allocation (%u-%u) failed", rpool->proxy_port[0], rpool->proxy_port[1]); reason = PFRES_MAPFAILED; goto notrans; } break; case PF_BINAT: switch (pd->dir) { case PF_OUT: if (rpool->cur->addr.type == PF_ADDR_DYNIFTL){ switch (pd->af) { #ifdef INET case AF_INET: if (rpool->cur->addr.p.dyn-> pfid_acnt4 < 1) { reason = PFRES_MAPFAILED; goto notrans; } pf_poolmask(naddr, &rpool->cur->addr.p.dyn->pfid_addr4, &rpool->cur->addr.p.dyn->pfid_mask4, &pd->nsaddr, AF_INET); break; #endif /* INET */ #ifdef INET6 case AF_INET6: if (rpool->cur->addr.p.dyn-> pfid_acnt6 < 1) { reason = PFRES_MAPFAILED; goto notrans; } pf_poolmask(naddr, &rpool->cur->addr.p.dyn->pfid_addr6, &rpool->cur->addr.p.dyn->pfid_mask6, &pd->nsaddr, AF_INET6); break; #endif /* INET6 */ } } else pf_poolmask(naddr, &rpool->cur->addr.v.a.addr, &rpool->cur->addr.v.a.mask, &pd->nsaddr, pd->af); break; case PF_IN: if (r->src.addr.type == PF_ADDR_DYNIFTL) { switch (pd->af) { #ifdef INET case AF_INET: if (r->src.addr.p.dyn->pfid_acnt4 < 1) { reason = PFRES_MAPFAILED; goto notrans; } pf_poolmask(naddr, &r->src.addr.p.dyn->pfid_addr4, &r->src.addr.p.dyn->pfid_mask4, &pd->ndaddr, AF_INET); break; #endif /* INET */ #ifdef INET6 case AF_INET6: if (r->src.addr.p.dyn->pfid_acnt6 < 1) { reason = PFRES_MAPFAILED; goto notrans; } pf_poolmask(naddr, &r->src.addr.p.dyn->pfid_addr6, &r->src.addr.p.dyn->pfid_mask6, &pd->ndaddr, AF_INET6); break; #endif /* INET6 */ } } else pf_poolmask(naddr, &r->src.addr.v.a.addr, &r->src.addr.v.a.mask, &pd->ndaddr, pd->af); break; } break; case PF_RDR: { struct pf_state_key_cmp key; int tries; uint16_t cut, low, high, nport; reason = pf_map_addr_sn(pd->af, r, &pd->nsaddr, naddr, &(pd->naf), NULL, NULL, rpool, PF_SN_NAT); if (reason != 0) goto notrans; if ((rpool->opts & PF_POOL_TYPEMASK) == PF_POOL_BITMASK) pf_poolmask(naddr, naddr, &rpool->cur->addr.v.a.mask, &pd->ndaddr, pd->af); /* Do not change SCTP ports. */ if (pd->proto == IPPROTO_SCTP) break; if (rpool->proxy_port[1]) { uint32_t tmp_nport; uint16_t div; div = r->rdr.proxy_port[1] - r->rdr.proxy_port[0] + 1; div = (div == 0) ? 1 : div; tmp_nport = ((ntohs(pd->ndport) - ntohs(r->dst.port[0])) % div) + rpool->proxy_port[0]; /* Wrap around if necessary. */ if (tmp_nport > 65535) tmp_nport -= 65535; nport = htons((uint16_t)tmp_nport); } else if (rpool->proxy_port[0]) nport = htons(rpool->proxy_port[0]); else nport = pd->ndport; /* * Update the destination port. */ *nportp = nport; /* * Do we have a source port conflict in the stack state? Try to * modulate the source port if so. Note that this is racy since * the state lookup may not find any matches here but will once * pf_create_state() actually instantiates the state. */ bzero(&key, sizeof(key)); key.af = pd->af; key.proto = pd->proto; key.port[0] = pd->nsport; pf_addrcpy(&key.addr[0], &pd->nsaddr, key.af); key.port[1] = nport; pf_addrcpy(&key.addr[1], naddr, key.af); if (!pf_find_state_all_exists(&key, PF_OUT)) break; tries = 0; low = 50001; /* XXX-MJ PF_NAT_PROXY_PORT_LOW/HIGH */ high = 65535; cut = arc4random() % (1 + high - low) + low; for (uint32_t tmp = cut; tmp <= high && tmp <= UINT16_MAX && tries < V_pf_rdr_srcport_rewrite_tries; tmp++, tries++) { key.port[0] = htons(tmp); if (!pf_find_state_all_exists(&key, PF_OUT)) { /* Update the source port. */ ctx->nk->port[0] = htons(tmp); goto out; } } for (uint32_t tmp = cut - 1; tmp >= low && tries < V_pf_rdr_srcport_rewrite_tries; tmp--, tries++) { key.port[0] = htons(tmp); if (!pf_find_state_all_exists(&key, PF_OUT)) { /* Update the source port. */ ctx->nk->port[0] = htons(tmp); goto out; } } /* * We failed to find a match. Push on ahead anyway, let * pf_state_insert() be the arbiter of whether the state * conflict is tolerable. In particular, with TCP connections * the state may be reused if the TCP state is terminal. */ DPFPRINTF(PF_DEBUG_MISC, "pf: RDR source port allocation failed"); break; out: DPFPRINTF(PF_DEBUG_MISC, "pf: RDR source port allocation %u->%u", ntohs(pd->nsport), ntohs(ctx->nk->port[0])); break; } default: panic("%s: unknown action %u", __func__, r->action); } /* Return success only if translation really happened. */ if (bcmp(ctx->sk, ctx->nk, sizeof(struct pf_state_key_cmp))) { return (PFRES_MATCH); } reason = PFRES_MAX; notrans: uma_zfree(V_pf_state_key_z, ctx->nk); uma_zfree(V_pf_state_key_z, ctx->sk); ctx->sk = ctx->nk = NULL; return (reason); } int pf_get_transaddr_af(struct pf_krule *r, struct pf_pdesc *pd) { #if defined(INET) && defined(INET6) struct pf_addr ndaddr, nsaddr, naddr; u_int16_t nport = 0; int prefixlen = 96; bzero(&nsaddr, sizeof(nsaddr)); bzero(&ndaddr, sizeof(ndaddr)); if (V_pf_status.debug >= PF_DEBUG_MISC) { printf("pf: af-to %s %s, ", pd->naf == AF_INET ? "inet" : "inet6", TAILQ_EMPTY(&r->rdr.list) ? "nat" : "rdr"); pf_print_host(&pd->nsaddr, pd->nsport, pd->af); printf(" -> "); pf_print_host(&pd->ndaddr, pd->ndport, pd->af); printf("\n"); } if (TAILQ_EMPTY(&r->nat.list)) panic("pf_get_transaddr_af: no nat pool for source address"); /* get source address and port */ if (pf_get_sport(pd, r, &nsaddr, &nport, r->nat.proxy_port[0], r->nat.proxy_port[1], &r->nat, NULL, PF_SN_NAT)) { DPFPRINTF(PF_DEBUG_MISC, "pf: af-to NAT proxy port allocation (%u-%u) failed", r->nat.proxy_port[0], r->nat.proxy_port[1]); return (-1); } if (pd->proto == IPPROTO_ICMPV6 && pd->naf == AF_INET) { pd->ndport = ntohs(pd->ndport); if (pd->ndport == ICMP6_ECHO_REQUEST) pd->ndport = ICMP_ECHO; else if (pd->ndport == ICMP6_ECHO_REPLY) pd->ndport = ICMP_ECHOREPLY; pd->ndport = htons(pd->ndport); } else if (pd->proto == IPPROTO_ICMP && pd->naf == AF_INET6) { pd->nsport = ntohs(pd->nsport); if (pd->ndport == ICMP_ECHO) pd->ndport = ICMP6_ECHO_REQUEST; else if (pd->ndport == ICMP_ECHOREPLY) pd->ndport = ICMP6_ECHO_REPLY; pd->nsport = htons(pd->nsport); } /* get the destination address and port */ if (! TAILQ_EMPTY(&r->rdr.list)) { if (pf_map_addr_sn(pd->naf, r, &nsaddr, &naddr, &(pd->naf), NULL, NULL, &r->rdr, PF_SN_NAT)) return (-1); if (r->rdr.proxy_port[0]) pd->ndport = htons(r->rdr.proxy_port[0]); if (pd->naf == AF_INET) { /* The prefix is the IPv4 rdr address */ prefixlen = in_mask2len( (struct in_addr *)&r->rdr.cur->addr.v.a.mask); inet_nat46(pd->naf, &pd->ndaddr, &ndaddr, &naddr, prefixlen); } else { /* The prefix is the IPv6 rdr address */ prefixlen = in6_mask2len( (struct in6_addr *)&r->rdr.cur->addr.v.a.mask, NULL); inet_nat64(pd->naf, &pd->ndaddr, &ndaddr, &naddr, prefixlen); } } else { if (pd->naf == AF_INET) { /* The prefix is the IPv6 dst address */ prefixlen = in6_mask2len( (struct in6_addr *)&r->dst.addr.v.a.mask, NULL); if (prefixlen < 32) prefixlen = 96; inet_nat64(pd->naf, &pd->ndaddr, &ndaddr, &pd->ndaddr, prefixlen); } else { /* * The prefix is the IPv6 nat address * (that was stored in pd->nsaddr) */ prefixlen = in6_mask2len( (struct in6_addr *)&r->nat.cur->addr.v.a.mask, NULL); if (prefixlen > 96) prefixlen = 96; inet_nat64(pd->naf, &pd->ndaddr, &ndaddr, &nsaddr, prefixlen); } } pf_addrcpy(&pd->nsaddr, &nsaddr, pd->naf); pf_addrcpy(&pd->ndaddr, &ndaddr, pd->naf); if (V_pf_status.debug >= PF_DEBUG_MISC) { printf("pf: af-to %s done, prefixlen %d, ", pd->naf == AF_INET ? "inet" : "inet6", prefixlen); pf_print_host(&pd->nsaddr, pd->nsport, pd->naf); printf(" -> "); pf_print_host(&pd->ndaddr, pd->ndport, pd->naf); printf("\n"); } return (0); #else return (-1); #endif }