/* $NetBSD: nattraversal.c,v 1.6.6.2 2009/05/18 17:01:07 tteras Exp $ */ /* * Copyright (C) 2004 SuSE Linux AG, Nuernberg, Germany. * Contributed by: Michal Ludvig , SUSE Labs * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. 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. * 3. Neither the name of the project nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE PROJECT 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 PROJECT 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. */ #include "config.h" #include #include #ifdef __linux__ #include #endif #if defined(__NetBSD__) || defined (__FreeBSD__) #include #endif #include #include #include #include #include #include "var.h" #include "misc.h" #include "vmbuf.h" #include "plog.h" #include "debug.h" #include "localconf.h" #include "remoteconf.h" #include "sockmisc.h" #include "isakmp_var.h" #include "isakmp.h" #include "oakley.h" #include "ipsec_doi.h" #include "vendorid.h" #include "handler.h" #include "crypto_openssl.h" #include "schedule.h" #include "nattraversal.h" #include "grabmyaddr.h" struct natt_ka_addrs { struct sockaddr *src; struct sockaddr *dst; unsigned in_use; TAILQ_ENTRY(natt_ka_addrs) chain; }; static TAILQ_HEAD(_natt_ka_addrs, natt_ka_addrs) ka_tree; /* * check if the given vid is NAT-T. */ int natt_vendorid (int vid) { return ( #ifdef ENABLE_NATT_00 vid == VENDORID_NATT_00 || #endif #ifdef ENABLE_NATT_01 vid == VENDORID_NATT_01 || #endif #ifdef ENABLE_NATT_02 vid == VENDORID_NATT_02 || vid == VENDORID_NATT_02_N || #endif #ifdef ENABLE_NATT_03 vid == VENDORID_NATT_03 || #endif #ifdef ENABLE_NATT_04 vid == VENDORID_NATT_04 || #endif #ifdef ENABLE_NATT_05 vid == VENDORID_NATT_05 || #endif #ifdef ENABLE_NATT_06 vid == VENDORID_NATT_06 || #endif #ifdef ENABLE_NATT_07 vid == VENDORID_NATT_07 || #endif #ifdef ENABLE_NATT_08 vid == VENDORID_NATT_08 || #endif /* Always enable NATT RFC if ENABLE_NATT */ vid == VENDORID_NATT_RFC); } vchar_t * natt_hash_addr (struct ph1handle *iph1, struct sockaddr *addr) { vchar_t *natd; vchar_t *buf; char *ptr; void *addr_ptr, *addr_port; size_t buf_size, addr_size; plog (LLV_INFO, LOCATION, addr, "Hashing %s with algo #%d %s\n", saddr2str(addr), iph1->approval->hashtype, (iph1->rmconf->nat_traversal == NATT_FORCE)?"(NAT-T forced)":""); if (addr->sa_family == AF_INET) { addr_size = sizeof (struct in_addr); /* IPv4 address */ addr_ptr = &((struct sockaddr_in *)addr)->sin_addr; addr_port = &((struct sockaddr_in *)addr)->sin_port; } else if (addr->sa_family == AF_INET6) { addr_size = sizeof (struct in6_addr); /* IPv6 address */ addr_ptr = &((struct sockaddr_in6 *)addr)->sin6_addr; addr_port = &((struct sockaddr_in6 *)addr)->sin6_port; } else { plog (LLV_ERROR, LOCATION, addr, "Unsupported address family #0x%x\n", addr->sa_family); return NULL; } buf_size = 2 * sizeof (cookie_t); /* CKY-I + CKY+R */ buf_size += addr_size + 2; /* Address + Port */ if ((buf = vmalloc (buf_size)) == NULL) return NULL; ptr = buf->v; /* Copy-in CKY-I */ memcpy (ptr, iph1->index.i_ck, sizeof (cookie_t)); ptr += sizeof (cookie_t); /* Copy-in CKY-I */ memcpy (ptr, iph1->index.r_ck, sizeof (cookie_t)); ptr += sizeof (cookie_t); /* Copy-in Address (or zeroes if NATT_FORCE) */ if (iph1->rmconf->nat_traversal == NATT_FORCE) memset (ptr, 0, addr_size); else memcpy (ptr, addr_ptr, addr_size); ptr += addr_size; /* Copy-in Port number */ memcpy (ptr, addr_port, 2); natd = oakley_hash (buf, iph1); vfree(buf); return natd; } int natt_compare_addr_hash (struct ph1handle *iph1, vchar_t *natd_received, int natd_seq) { vchar_t *natd_computed; u_int32_t flag; int verified = 0; if (iph1->rmconf->nat_traversal == NATT_FORCE) return verified; if (natd_seq == 0) { natd_computed = natt_hash_addr (iph1, iph1->local); flag = NAT_DETECTED_ME; } else { natd_computed = natt_hash_addr (iph1, iph1->remote); flag = NAT_DETECTED_PEER; } if (natd_computed == NULL) { plog(LLV_ERROR, LOCATION, NULL, "natd_computed allocation failed\n"); return verified; /* XXX should abort */ } if (natd_received->l == natd_computed->l && memcmp (natd_received->v, natd_computed->v, natd_received->l) == 0) { iph1->natt_flags &= ~flag; verified = 1; } vfree (natd_computed); return verified; } int natt_udp_encap (int encmode) { return (encmode == IPSECDOI_ATTR_ENC_MODE_UDPTUNNEL_RFC || encmode == IPSECDOI_ATTR_ENC_MODE_UDPTRNS_RFC || encmode == IPSECDOI_ATTR_ENC_MODE_UDPTUNNEL_DRAFT || encmode == IPSECDOI_ATTR_ENC_MODE_UDPTRNS_DRAFT); } int natt_fill_options (struct ph1natt_options *opts, int version) { if (! opts) return -1; opts->version = version; switch (version) { case VENDORID_NATT_00: case VENDORID_NATT_01: opts->float_port = 0; /* No port floating for those drafts */ opts->payload_nat_d = ISAKMP_NPTYPE_NATD_DRAFT; opts->payload_nat_oa = ISAKMP_NPTYPE_NATOA_DRAFT; opts->mode_udp_tunnel = IPSECDOI_ATTR_ENC_MODE_UDPTUNNEL_DRAFT; opts->mode_udp_transport = IPSECDOI_ATTR_ENC_MODE_UDPTRNS_DRAFT; opts->encaps_type = UDP_ENCAP_ESPINUDP_NON_IKE; break; case VENDORID_NATT_02: case VENDORID_NATT_02_N: case VENDORID_NATT_03: opts->float_port = lcconf->port_isakmp_natt; opts->payload_nat_d = ISAKMP_NPTYPE_NATD_DRAFT; opts->payload_nat_oa = ISAKMP_NPTYPE_NATOA_DRAFT; opts->mode_udp_tunnel = IPSECDOI_ATTR_ENC_MODE_UDPTUNNEL_DRAFT; opts->mode_udp_transport = IPSECDOI_ATTR_ENC_MODE_UDPTRNS_DRAFT; opts->encaps_type = UDP_ENCAP_ESPINUDP; break; case VENDORID_NATT_04: case VENDORID_NATT_05: case VENDORID_NATT_06: case VENDORID_NATT_07: case VENDORID_NATT_08: opts->float_port = lcconf->port_isakmp_natt; opts->payload_nat_d = ISAKMP_NPTYPE_NATD_BADDRAFT; opts->payload_nat_oa = ISAKMP_NPTYPE_NATOA_BADDRAFT; opts->mode_udp_tunnel = IPSECDOI_ATTR_ENC_MODE_UDPTUNNEL_RFC; opts->mode_udp_transport = IPSECDOI_ATTR_ENC_MODE_UDPTRNS_RFC; opts->encaps_type = UDP_ENCAP_ESPINUDP; break; case VENDORID_NATT_RFC: opts->float_port = lcconf->port_isakmp_natt; opts->payload_nat_d = ISAKMP_NPTYPE_NATD_RFC; opts->payload_nat_oa = ISAKMP_NPTYPE_NATOA_RFC; opts->mode_udp_tunnel = IPSECDOI_ATTR_ENC_MODE_UDPTUNNEL_RFC; opts->mode_udp_transport = IPSECDOI_ATTR_ENC_MODE_UDPTRNS_RFC; opts->encaps_type = UDP_ENCAP_ESPINUDP; break; default: plog(LLV_ERROR, LOCATION, NULL, "unsupported NAT-T version: %s\n", vid_string_by_id(version)); return -1; } opts->mode_udp_diff = opts->mode_udp_tunnel - IPSECDOI_ATTR_ENC_MODE_TUNNEL; return 0; } void natt_float_ports (struct ph1handle *iph1) { if (! (iph1->natt_flags & NAT_DETECTED) ) return; if (! iph1->natt_options->float_port){ /* Drafts 00 / 01, just schedule keepalive */ natt_keepalive_add_ph1 (iph1); return; } set_port (iph1->local, iph1->natt_options->float_port); set_port (iph1->remote, iph1->natt_options->float_port); iph1->natt_flags |= NAT_PORTS_CHANGED | NAT_ADD_NON_ESP_MARKER; natt_keepalive_add_ph1 (iph1); } void natt_handle_vendorid (struct ph1handle *iph1, int vid_numeric) { if (! iph1->natt_options) iph1->natt_options = racoon_calloc (1, sizeof (*iph1->natt_options)); if (! iph1->natt_options) { plog (LLV_ERROR, LOCATION, NULL, "Allocating memory for natt_options failed!\n"); return; } if (iph1->natt_options->version < vid_numeric) if (natt_fill_options (iph1->natt_options, vid_numeric) == 0) iph1->natt_flags |= NAT_ANNOUNCED; } static void natt_keepalive_delete (struct natt_ka_addrs *ka) { TAILQ_REMOVE (&ka_tree, ka, chain); racoon_free (ka->src); racoon_free (ka->dst); racoon_free (ka); } /* NAT keepalive functions */ static void natt_keepalive_send (void *param) { struct natt_ka_addrs *ka, *next = NULL; char keepalive_packet[] = { 0xff }; size_t len; int s; for (ka = TAILQ_FIRST(&ka_tree); ka; ka = next) { next = TAILQ_NEXT(ka, chain); s = getsockmyaddr(ka->src); if (s == -1) { natt_keepalive_delete(ka); continue; } plog (LLV_DEBUG, LOCATION, NULL, "KA: %s\n", saddr2str_fromto("%s->%s", ka->src, ka->dst)); len = sendfromto(s, keepalive_packet, sizeof (keepalive_packet), ka->src, ka->dst, 1); if (len == -1) plog(LLV_ERROR, LOCATION, NULL, "KA: sendfromto failed: %s\n", strerror (errno)); } sched_new (lcconf->natt_ka_interval, natt_keepalive_send, NULL); } void natt_keepalive_init (void) { TAILQ_INIT(&ka_tree); /* To disable sending KAs set natt_ka_interval=0 */ if (lcconf->natt_ka_interval > 0) sched_new (lcconf->natt_ka_interval, natt_keepalive_send, NULL); } int natt_keepalive_add (struct sockaddr *src, struct sockaddr *dst) { struct natt_ka_addrs *ka = NULL, *new_addr; TAILQ_FOREACH (ka, &ka_tree, chain) { if (cmpsaddrstrict(ka->src, src) == 0 && cmpsaddrstrict(ka->dst, dst) == 0) { ka->in_use++; plog (LLV_INFO, LOCATION, NULL, "KA found: %s (in_use=%u)\n", saddr2str_fromto("%s->%s", src, dst), ka->in_use); return 0; } } plog (LLV_INFO, LOCATION, NULL, "KA list add: %s\n", saddr2str_fromto("%s->%s", src, dst)); new_addr = (struct natt_ka_addrs *)racoon_malloc(sizeof(*new_addr)); if (! new_addr) { plog (LLV_ERROR, LOCATION, NULL, "Can't allocate new KA list item\n"); return -1; } if ((new_addr->src = dupsaddr(src)) == NULL) { racoon_free(new_addr); plog (LLV_ERROR, LOCATION, NULL, "Can't allocate new KA list item\n"); return -1; } if ((new_addr->dst = dupsaddr(dst)) == NULL) { racoon_free(new_addr); plog (LLV_ERROR, LOCATION, NULL, "Can't allocate new KA list item\n"); return -1; } new_addr->in_use = 1; TAILQ_INSERT_TAIL(&ka_tree, new_addr, chain); return 0; } int natt_keepalive_add_ph1 (struct ph1handle *iph1) { int ret = 0; /* Should only the NATed host send keepalives? If yes, add '(iph1->natt_flags & NAT_DETECTED_ME)' to the following condition. */ if (iph1->natt_flags & NAT_DETECTED && ! (iph1->natt_flags & NAT_KA_QUEUED)) { ret = natt_keepalive_add (iph1->local, iph1->remote); if (ret == 0) iph1->natt_flags |= NAT_KA_QUEUED; } return ret; } void natt_keepalive_remove (struct sockaddr *src, struct sockaddr *dst) { struct natt_ka_addrs *ka, *next = NULL; plog (LLV_INFO, LOCATION, NULL, "KA remove: %s\n", saddr2str_fromto("%s->%s", src, dst)); for (ka = TAILQ_FIRST(&ka_tree); ka; ka = next) { next = TAILQ_NEXT(ka, chain); plog (LLV_DEBUG, LOCATION, NULL, "KA tree dump: %s (in_use=%u)\n", saddr2str_fromto("%s->%s", src, dst), ka->in_use); if (cmpsaddrstrict(ka->src, src) == 0 && cmpsaddrstrict(ka->dst, dst) == 0 && -- ka->in_use <= 0) { plog (LLV_DEBUG, LOCATION, NULL, "KA removing this one...\n"); natt_keepalive_delete (ka); /* Should we break here? Every pair of addresses should be inserted only once, but who knows :-) Lets traverse the whole list... */ } } } static struct remoteconf * natt_enabled_in_rmconf_stub (struct remoteconf *rmconf, void *data) { return (rmconf->nat_traversal ? rmconf : NULL); } int natt_enabled_in_rmconf () { return foreachrmconf (natt_enabled_in_rmconf_stub, NULL) != NULL; } struct payload_list * isakmp_plist_append_natt_vids (struct payload_list *plist, vchar_t *vid_natt[MAX_NATT_VID_COUNT]){ int i, vid_natt_i = 0; if(vid_natt == NULL) return NULL; for (i = 0; i < MAX_NATT_VID_COUNT; i++) vid_natt[i]=NULL; /* Puts the olders VIDs last, as some implementations may choose the first * NATT VID given */ /* Always set RFC VID */ if ((vid_natt[vid_natt_i] = set_vendorid(VENDORID_NATT_RFC)) != NULL) vid_natt_i++; #ifdef ENABLE_NATT_08 if ((vid_natt[vid_natt_i] = set_vendorid(VENDORID_NATT_08)) != NULL) vid_natt_i++; #endif #ifdef ENABLE_NATT_07 if ((vid_natt[vid_natt_i] = set_vendorid(VENDORID_NATT_07)) != NULL) vid_natt_i++; #endif #ifdef ENABLE_NATT_06 if ((vid_natt[vid_natt_i] = set_vendorid(VENDORID_NATT_06)) != NULL) vid_natt_i++; #endif #ifdef ENABLE_NATT_05 if ((vid_natt[vid_natt_i] = set_vendorid(VENDORID_NATT_05)) != NULL) vid_natt_i++; #endif #ifdef ENABLE_NATT_04 if ((vid_natt[vid_natt_i] = set_vendorid(VENDORID_NATT_04)) != NULL) vid_natt_i++; #endif #ifdef ENABLE_NATT_03 if ((vid_natt[vid_natt_i] = set_vendorid(VENDORID_NATT_03)) != NULL) vid_natt_i++; #endif #ifdef ENABLE_NATT_02 if ((vid_natt[vid_natt_i] = set_vendorid(VENDORID_NATT_02)) != NULL) vid_natt_i++; if ((vid_natt[vid_natt_i] = set_vendorid(VENDORID_NATT_02_N)) != NULL) vid_natt_i++; #endif #ifdef ENABLE_NATT_01 if ((vid_natt[vid_natt_i] = set_vendorid(VENDORID_NATT_01)) != NULL) vid_natt_i++; #endif #ifdef ENABLE_NATT_00 if ((vid_natt[vid_natt_i] = set_vendorid(VENDORID_NATT_00)) != NULL) vid_natt_i++; #endif /* set VID payload for NAT-T */ for (i = 0; i < vid_natt_i; i++) plist = isakmp_plist_append(plist, vid_natt[i], ISAKMP_NPTYPE_VID); return plist; }