// SPDX-License-Identifier: GPL-2.0-or-later /* NHRP peer functions * Copyright (c) 2014-2015 Timo Teräs */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include #include "zebra.h" #include "memory.h" #include "frrevent.h" #include "hash.h" #include "network.h" #include "nhrpd.h" #include "nhrp_protocol.h" #include "os.h" DEFINE_MTYPE_STATIC(NHRPD, NHRP_PEER, "NHRP peer entry"); struct ipv6hdr { uint8_t priority_version; uint8_t flow_lbl[3]; uint16_t payload_len; uint8_t nexthdr; uint8_t hop_limit; struct in6_addr saddr; struct in6_addr daddr; }; static void nhrp_packet_debug(struct zbuf *zb, const char *dir); static void nhrp_peer_check_delete(struct nhrp_peer *p) { struct nhrp_interface *nifp = p->ifp->info; if (p->ref || notifier_active(&p->notifier_list)) return; debugf(NHRP_DEBUG_COMMON, "Deleting peer ref:%d remote:%pSU local:%pSU", p->ref, &p->vc->remote.nbma, &p->vc->local.nbma); EVENT_OFF(p->t_fallback); EVENT_OFF(p->t_timer); if (nifp->peer_hash) hash_release(nifp->peer_hash, p); nhrp_interface_notify_del(p->ifp, &p->ifp_notifier); nhrp_vc_notify_del(p->vc, &p->vc_notifier); XFREE(MTYPE_NHRP_PEER, p); } static void nhrp_peer_notify_up(struct event *t) { struct nhrp_peer *p = EVENT_ARG(t); struct nhrp_vc *vc = p->vc; struct interface *ifp = p->ifp; struct nhrp_interface *nifp = ifp->info; p->t_fallback = NULL; if (nifp->enabled && (!nifp->ipsec_profile || vc->ipsec)) { p->online = 1; nhrp_peer_ref(p); notifier_call(&p->notifier_list, NOTIFY_PEER_UP); nhrp_peer_unref(p); } } static void __nhrp_peer_check(struct nhrp_peer *p) { struct nhrp_vc *vc = p->vc; struct interface *ifp = p->ifp; struct nhrp_interface *nifp = ifp->info; unsigned online; online = nifp->enabled && (!nifp->ipsec_profile || vc->ipsec); if (p->online != online) { EVENT_OFF(p->t_fallback); if (online && notifier_active(&p->notifier_list)) { /* If we requested the IPsec connection, delay * the up notification a bit to allow things * settle down. This allows IKE to install * SPDs and SAs. */ event_add_timer_msec(master, nhrp_peer_notify_up, p, 50, &p->t_fallback); } else { nhrp_peer_ref(p); p->online = online; if (online) { notifier_call(&p->notifier_list, NOTIFY_PEER_UP); } else { p->requested = p->fallback_requested = 0; notifier_call(&p->notifier_list, NOTIFY_PEER_DOWN); } nhrp_peer_unref(p); } } } static void nhrp_peer_vc_notify(struct notifier_block *n, unsigned long cmd) { struct nhrp_peer *p = container_of(n, struct nhrp_peer, vc_notifier); switch (cmd) { case NOTIFY_VC_IPSEC_CHANGED: __nhrp_peer_check(p); break; case NOTIFY_VC_IPSEC_UPDATE_NBMA: nhrp_peer_ref(p); notifier_call(&p->notifier_list, NOTIFY_PEER_NBMA_CHANGING); nhrp_peer_unref(p); break; } } static void nhrp_peer_ifp_notify(struct notifier_block *n, unsigned long cmd) { struct nhrp_peer *p = container_of(n, struct nhrp_peer, ifp_notifier); struct nhrp_interface *nifp; struct nhrp_vc *vc; nhrp_peer_ref(p); switch (cmd) { case NOTIFY_INTERFACE_UP: case NOTIFY_INTERFACE_DOWN: __nhrp_peer_check(p); break; case NOTIFY_INTERFACE_NBMA_CHANGED: /* Source NBMA changed, rebind to new VC */ nifp = p->ifp->info; vc = nhrp_vc_get(&nifp->nbma, &p->vc->remote.nbma, 1); if (vc && p->vc != vc) { nhrp_vc_notify_del(p->vc, &p->vc_notifier); p->vc = vc; nhrp_vc_notify_add(p->vc, &p->vc_notifier, nhrp_peer_vc_notify); __nhrp_peer_check(p); } fallthrough; /* to post config update */ case NOTIFY_INTERFACE_ADDRESS_CHANGED: notifier_call(&p->notifier_list, NOTIFY_PEER_IFCONFIG_CHANGED); break; case NOTIFY_INTERFACE_IPSEC_CHANGED: __nhrp_peer_check(p); notifier_call(&p->notifier_list, NOTIFY_PEER_IFCONFIG_CHANGED); break; case NOTIFY_INTERFACE_MTU_CHANGED: notifier_call(&p->notifier_list, NOTIFY_PEER_MTU_CHANGED); break; } nhrp_peer_unref(p); } static unsigned int nhrp_peer_key(const void *peer_data) { const struct nhrp_peer *p = peer_data; return sockunion_hash(&p->vc->remote.nbma); } static bool nhrp_peer_cmp(const void *cache_data, const void *key_data) { const struct nhrp_peer *a = cache_data; const struct nhrp_peer *b = key_data; return a->ifp == b->ifp && a->vc == b->vc; } static void *nhrp_peer_create(void *data) { struct nhrp_peer *p, *key = data; p = XMALLOC(MTYPE_NHRP_PEER, sizeof(*p)); *p = (struct nhrp_peer){ .ref = 0, .ifp = key->ifp, .vc = key->vc, .notifier_list = NOTIFIER_LIST_INITIALIZER(&p->notifier_list), }; nhrp_vc_notify_add(p->vc, &p->vc_notifier, nhrp_peer_vc_notify); nhrp_interface_notify_add(p->ifp, &p->ifp_notifier, nhrp_peer_ifp_notify); return p; } static void do_peer_hash_free(void *hb_data) { struct nhrp_peer *p = (struct nhrp_peer *)hb_data; nhrp_peer_check_delete(p); } void nhrp_peer_interface_del(struct interface *ifp) { struct nhrp_interface *nifp = ifp->info; debugf(NHRP_DEBUG_COMMON, "Cleaning up undeleted peer entries (%lu)", nifp->peer_hash ? nifp->peer_hash->count : 0); hash_clean_and_free(&nifp->peer_hash, do_peer_hash_free); } struct nhrp_peer *nhrp_peer_get(struct interface *ifp, const union sockunion *remote_nbma) { struct nhrp_interface *nifp = ifp->info; struct nhrp_peer key, *p; struct nhrp_vc *vc; if (!nifp->peer_hash) { nifp->peer_hash = hash_create(nhrp_peer_key, nhrp_peer_cmp, "NHRP Peer Hash"); if (!nifp->peer_hash) return NULL; } vc = nhrp_vc_get(&nifp->nbma, remote_nbma, 1); if (!vc) return NULL; key.ifp = ifp; key.vc = vc; p = hash_get(nifp->peer_hash, &key, nhrp_peer_create); nhrp_peer_ref(p); if (p->ref == 1) __nhrp_peer_check(p); return p; } struct nhrp_peer *nhrp_peer_ref(struct nhrp_peer *p) { if (p) p->ref++; return p; } void nhrp_peer_unref(struct nhrp_peer *p) { if (p) { p->ref--; nhrp_peer_check_delete(p); } } static void nhrp_peer_request_timeout(struct event *t) { struct nhrp_peer *p = EVENT_ARG(t); struct nhrp_vc *vc = p->vc; struct interface *ifp = p->ifp; struct nhrp_interface *nifp = ifp->info; if (p->online) return; if (nifp->ipsec_fallback_profile && !p->prio && !p->fallback_requested) { p->fallback_requested = 1; vici_request_vc(nifp->ipsec_fallback_profile, &vc->local.nbma, &vc->remote.nbma, p->prio); event_add_timer(master, nhrp_peer_request_timeout, p, 30, &p->t_fallback); } else { p->requested = p->fallback_requested = 0; } } static void nhrp_peer_defer_vici_request(struct event *t) { struct nhrp_peer *p = EVENT_ARG(t); struct nhrp_vc *vc = p->vc; struct interface *ifp = p->ifp; struct nhrp_interface *nifp = ifp->info; EVENT_OFF(p->t_timer); if (p->online) { debugf(NHRP_DEBUG_COMMON, "IPsec connection to %pSU already established", &vc->remote.nbma); } else { vici_request_vc(nifp->ipsec_profile, &vc->local.nbma, &vc->remote.nbma, p->prio); event_add_timer(master, nhrp_peer_request_timeout, p, (nifp->ipsec_fallback_profile && !p->prio) ? 15 : 30, &p->t_fallback); } } int nhrp_peer_check(struct nhrp_peer *p, int establish) { struct nhrp_vc *vc = p->vc; struct interface *ifp = p->ifp; struct nhrp_interface *nifp = ifp->info; if (p->online) return 1; if (!establish) return 0; if (p->requested) return 0; if (!nifp->ipsec_profile) return 0; if (sockunion_family(&vc->local.nbma) == AF_UNSPEC) return 0; if (vc->ipsec) return 1; p->prio = establish > 1; p->requested = 1; /* All NHRP registration requests are prioritized */ if (p->prio) { vici_request_vc(nifp->ipsec_profile, &vc->local.nbma, &vc->remote.nbma, p->prio); event_add_timer(master, nhrp_peer_request_timeout, p, (nifp->ipsec_fallback_profile && !p->prio) ? 15 : 30, &p->t_fallback); } else { /* Maximum timeout is 1 second */ int r_time_ms = frr_weak_random() % 1000; debugf(NHRP_DEBUG_COMMON, "Initiating IPsec connection request to %pSU after %d ms:", &vc->remote.nbma, r_time_ms); event_add_timer_msec(master, nhrp_peer_defer_vici_request, p, r_time_ms, &p->t_timer); } return 0; } void nhrp_peer_notify_add(struct nhrp_peer *p, struct notifier_block *n, notifier_fn_t fn) { notifier_add(n, &p->notifier_list, fn); } void nhrp_peer_notify_del(struct nhrp_peer *p, struct notifier_block *n) { notifier_del(n, &p->notifier_list); nhrp_peer_check_delete(p); } void nhrp_peer_send(struct nhrp_peer *p, struct zbuf *zb) { nhrp_packet_debug(zb, "Send"); if (!p->online) return; debugf(NHRP_DEBUG_KERNEL, "PACKET: Send %pSU -> %pSU", &p->vc->local.nbma, &p->vc->remote.nbma); os_sendmsg(zb->head, zbuf_used(zb), p->ifp->ifindex, sockunion_get_addr(&p->vc->remote.nbma), sockunion_get_addrlen(&p->vc->remote.nbma), ETH_P_NHRP); zbuf_reset(zb); } static void nhrp_process_nat_extension(struct nhrp_packet_parser *pp, union sockunion *proto, union sockunion *cie_nbma) { union sockunion cie_proto; struct zbuf payload; struct nhrp_extension_header *ext; struct zbuf *extensions; if (!cie_nbma) return; sockunion_family(cie_nbma) = AF_UNSPEC; if (!proto || sockunion_family(proto) == AF_UNSPEC) return; /* Handle extensions */ extensions = zbuf_alloc(zbuf_used(&pp->extensions)); if (extensions) { zbuf_copy_peek(extensions, &pp->extensions, zbuf_used(&pp->extensions)); while ((ext = nhrp_ext_pull(extensions, &payload)) != NULL) { switch (htons(ext->type) & ~NHRP_EXTENSION_FLAG_COMPULSORY) { case NHRP_EXTENSION_NAT_ADDRESS: /* Process the NBMA and proto address in NAT * extension and update the cache without which * the neighbor table in the kernel contains the * source NBMA address which is not reachable * since it is behind a NAT device */ debugf(NHRP_DEBUG_COMMON, "shortcut res_resp: Processing NAT Extension for %pSU", proto); while (nhrp_cie_pull(&payload, pp->hdr, cie_nbma, &cie_proto)) { if (sockunion_family(&cie_proto) == AF_UNSPEC) continue; if (!sockunion_cmp(proto, &cie_proto)) { debugf(NHRP_DEBUG_COMMON, "cie_nbma for proto %pSU is %pSU", proto, cie_nbma); break; } } } } zbuf_free(extensions); } } static void nhrp_handle_resolution_req(struct nhrp_packet_parser *pp) { struct interface *ifp = pp->ifp; struct zbuf *zb, payload; struct nhrp_packet_header *hdr; struct nhrp_cie_header *cie; struct nhrp_extension_header *ext; struct nhrp_cache *c; union sockunion cie_nbma, cie_nbma_nat, cie_proto, *proto_addr, *nbma_addr, *claimed_nbma_addr; int holdtime, prefix_len, hostprefix_len; struct nhrp_interface *nifp = ifp->info; struct nhrp_peer *peer; size_t paylen; if (!(pp->if_ad->flags & NHRP_IFF_SHORTCUT)) { debugf(NHRP_DEBUG_COMMON, "Shortcuts disabled"); /* FIXME: Send error indication? */ return; } if (pp->if_ad->network_id && pp->route_type == NHRP_ROUTE_OFF_NBMA && pp->route_prefix.prefixlen < 8) { debugf(NHRP_DEBUG_COMMON, "Shortcut to more generic than /8 dropped"); return; } debugf(NHRP_DEBUG_COMMON, "Parsing and replying to Resolution Req"); if (nhrp_route_address(ifp, &pp->src_proto, NULL, &peer) != NHRP_ROUTE_NBMA_NEXTHOP) return; /* Copy payload CIE */ hostprefix_len = 8 * sockunion_get_addrlen(&pp->if_ad->addr); paylen = zbuf_used(&pp->payload); debugf(NHRP_DEBUG_COMMON, "shortcut res_rep: paylen %zu", paylen); while ((cie = nhrp_cie_pull(&pp->payload, pp->hdr, &cie_nbma, &cie_proto)) != NULL) { prefix_len = cie->prefix_length; debugf(NHRP_DEBUG_COMMON, "shortcut res_rep: parsing CIE with prefixlen=%u", prefix_len); if (prefix_len == 0 || prefix_len >= hostprefix_len) prefix_len = hostprefix_len; if (prefix_len != hostprefix_len && !(pp->hdr->flags & htons(NHRP_FLAG_REGISTRATION_UNIQUE))) { cie->code = NHRP_CODE_BINDING_NON_UNIQUE; continue; } /* We currently support only unique prefix registrations */ if (prefix_len != hostprefix_len) { cie->code = NHRP_CODE_ADMINISTRATIVELY_PROHIBITED; continue; } proto_addr = (sockunion_family(&cie_proto) == AF_UNSPEC) ? &pp->src_proto : &cie_proto; /* Check for this proto_addr in NHRP_NAT_EXTENSION */ nhrp_process_nat_extension(pp, proto_addr, &cie_nbma_nat); if (sockunion_family(&cie_nbma_nat) == AF_UNSPEC) { /* It may be possible that this resolution reply is * coming directly from NATTED Spoke and there is not * NAT Extension present */ debugf(NHRP_DEBUG_COMMON, "shortcut res_rep: No NAT Extension for %pSU", proto_addr); if (!sockunion_same(&pp->src_nbma, &pp->peer->vc->remote.nbma) && !nhrp_nhs_match_ip(&pp->peer->vc->remote.nbma, nifp)) { cie_nbma_nat = pp->peer->vc->remote.nbma; debugf(NHRP_DEBUG_COMMON, "shortcut res_rep: NAT detected using %pSU as cie_nbma", &cie_nbma_nat); } } if (sockunion_family(&cie_nbma_nat) != AF_UNSPEC) nbma_addr = &cie_nbma_nat; else if (sockunion_family(&cie_nbma) != AF_UNSPEC) nbma_addr = &cie_nbma; else nbma_addr = &pp->src_nbma; if (sockunion_family(&cie_nbma) != AF_UNSPEC) claimed_nbma_addr = &cie_nbma; else claimed_nbma_addr = &pp->src_nbma; holdtime = htons(cie->holding_time); debugf(NHRP_DEBUG_COMMON, "shortcut res_rep: holdtime is %u (if 0, using %u)", holdtime, pp->if_ad->holdtime); if (!holdtime) holdtime = pp->if_ad->holdtime; c = nhrp_cache_get(ifp, proto_addr, 1); if (!c) { debugf(NHRP_DEBUG_COMMON, "shortcut res_rep: no cache found"); cie->code = NHRP_CODE_INSUFFICIENT_RESOURCES; continue; } debugf(NHRP_DEBUG_COMMON, "shortcut res_rep: updating binding for nmba addr %pSU", nbma_addr); if (!nhrp_cache_update_binding( c, NHRP_CACHE_DYNAMIC, holdtime, nhrp_peer_get(pp->ifp, nbma_addr), htons(cie->mtu), nbma_addr, claimed_nbma_addr)) { cie->code = NHRP_CODE_ADMINISTRATIVELY_PROHIBITED; continue; } cie->code = NHRP_CODE_SUCCESS; } /* Create reply */ zb = zbuf_alloc(1500); hdr = nhrp_packet_push(zb, NHRP_PACKET_RESOLUTION_REPLY, &pp->src_nbma, &pp->src_proto, &pp->dst_proto); /* Copied information from request */ hdr->flags = pp->hdr->flags & htons(NHRP_FLAG_RESOLUTION_SOURCE_IS_ROUTER | NHRP_FLAG_RESOLUTION_SOURCE_STABLE); hdr->flags |= htons(NHRP_FLAG_RESOLUTION_DESTINATION_STABLE | NHRP_FLAG_RESOLUTION_AUTHORATIVE); hdr->u.request_id = pp->hdr->u.request_id; /* CIE payload for the reply packet */ cie = nhrp_cie_push(zb, NHRP_CODE_SUCCESS, &nifp->nbma, &pp->if_ad->addr); cie->holding_time = htons(pp->if_ad->holdtime); cie->mtu = htons(pp->if_ad->mtu); if (pp->if_ad->network_id && pp->route_type == NHRP_ROUTE_OFF_NBMA) cie->prefix_length = pp->route_prefix.prefixlen; else cie->prefix_length = 8 * sockunion_get_addrlen(&pp->if_ad->addr); /* Handle extensions */ while ((ext = nhrp_ext_pull(&pp->extensions, &payload)) != NULL) { switch (htons(ext->type) & ~NHRP_EXTENSION_FLAG_COMPULSORY) { case NHRP_EXTENSION_NAT_ADDRESS: ext = nhrp_ext_push(zb, hdr, NHRP_EXTENSION_NAT_ADDRESS); if (!ext) goto err; if (sockunion_family(&nifp->nat_nbma) != AF_UNSPEC) { cie = nhrp_cie_push(zb, NHRP_CODE_SUCCESS, &nifp->nat_nbma, &pp->if_ad->addr); if (!cie) goto err; cie->prefix_length = 8 * sockunion_get_addrlen( &pp->if_ad->addr); cie->mtu = htons(pp->if_ad->mtu); nhrp_ext_complete(zb, ext); } break; default: if (nhrp_ext_reply(zb, hdr, ifp, ext, &payload) < 0) goto err; break; } } nhrp_packet_complete(zb, hdr); nhrp_peer_send(peer, zb); err: nhrp_peer_unref(peer); zbuf_free(zb); } static void nhrp_handle_registration_request(struct nhrp_packet_parser *p) { struct interface *ifp = p->ifp; struct zbuf *zb, payload; struct nhrp_packet_header *hdr; struct nhrp_cie_header *cie; struct nhrp_extension_header *ext; struct nhrp_cache *c; union sockunion cie_nbma, cie_proto, *proto_addr, *nbma_addr, *nbma_natoa; int holdtime, prefix_len, hostprefix_len, natted = 0; size_t paylen; void *pay; debugf(NHRP_DEBUG_COMMON, "Parsing and replying to Registration Req"); hostprefix_len = 8 * sockunion_get_addrlen(&p->if_ad->addr); if (!sockunion_same(&p->src_nbma, &p->peer->vc->remote.nbma)) natted = 1; /* Create reply */ zb = zbuf_alloc(1500); hdr = nhrp_packet_push(zb, NHRP_PACKET_REGISTRATION_REPLY, &p->src_nbma, &p->src_proto, &p->if_ad->addr); /* Copied information from request */ hdr->flags = p->hdr->flags & htons(NHRP_FLAG_REGISTRATION_UNIQUE | NHRP_FLAG_REGISTRATION_NAT); hdr->u.request_id = p->hdr->u.request_id; /* Copy payload CIEs */ paylen = zbuf_used(&p->payload); pay = zbuf_pushn(zb, paylen); if (!pay) goto err; memcpy(pay, zbuf_pulln(&p->payload, paylen), paylen); zbuf_init(&payload, pay, paylen, paylen); while ((cie = nhrp_cie_pull(&payload, hdr, &cie_nbma, &cie_proto)) != NULL) { prefix_len = cie->prefix_length; if (prefix_len == 0 || prefix_len >= hostprefix_len) prefix_len = hostprefix_len; if (prefix_len != hostprefix_len && !(p->hdr->flags & htons(NHRP_FLAG_REGISTRATION_UNIQUE))) { cie->code = NHRP_CODE_BINDING_NON_UNIQUE; continue; } /* We currently support only unique prefix registrations */ if (prefix_len != hostprefix_len) { cie->code = NHRP_CODE_ADMINISTRATIVELY_PROHIBITED; continue; } proto_addr = (sockunion_family(&cie_proto) == AF_UNSPEC) ? &p->src_proto : &cie_proto; nbma_addr = (sockunion_family(&cie_nbma) == AF_UNSPEC) ? &p->src_nbma : &cie_nbma; nbma_natoa = NULL; if (natted) { nbma_natoa = (sockunion_family(&p->peer->vc->remote.nbma) == AF_UNSPEC) ? nbma_addr : &p->peer->vc->remote.nbma; } holdtime = htons(cie->holding_time); if (!holdtime) holdtime = p->if_ad->holdtime; c = nhrp_cache_get(ifp, proto_addr, 1); if (!c) { cie->code = NHRP_CODE_INSUFFICIENT_RESOURCES; continue; } if (!nhrp_cache_update_binding(c, NHRP_CACHE_DYNAMIC, holdtime, nhrp_peer_ref(p->peer), htons(cie->mtu), nbma_natoa, nbma_addr)) { cie->code = NHRP_CODE_ADMINISTRATIVELY_PROHIBITED; continue; } cie->code = NHRP_CODE_SUCCESS; } /* Handle extensions */ while ((ext = nhrp_ext_pull(&p->extensions, &payload)) != NULL) { switch (htons(ext->type) & ~NHRP_EXTENSION_FLAG_COMPULSORY) { case NHRP_EXTENSION_NAT_ADDRESS: ext = nhrp_ext_push(zb, hdr, NHRP_EXTENSION_NAT_ADDRESS); if (!ext) goto err; zbuf_copy(zb, &payload, zbuf_used(&payload)); if (natted) { cie = nhrp_cie_push(zb, NHRP_CODE_SUCCESS, &p->peer->vc->remote.nbma, &p->src_proto); cie->prefix_length = 8 * sockunion_get_addrlen( &p->if_ad->addr); cie->mtu = htons(p->if_ad->mtu); } nhrp_ext_complete(zb, ext); break; default: if (nhrp_ext_reply(zb, hdr, ifp, ext, &payload) < 0) goto err; break; } } nhrp_packet_complete(zb, hdr); nhrp_peer_send(p->peer, zb); err: zbuf_free(zb); } static int parse_ether_packet(struct zbuf *zb, uint16_t protocol_type, union sockunion *src, union sockunion *dst) { switch (protocol_type) { case ETH_P_IP: { struct iphdr *iph = zbuf_pull(zb, struct iphdr); if (iph) { if (src) sockunion_set(src, AF_INET, (uint8_t *)&iph->saddr, sizeof(iph->saddr)); if (dst) sockunion_set(dst, AF_INET, (uint8_t *)&iph->daddr, sizeof(iph->daddr)); } } break; case ETH_P_IPV6: { struct ipv6hdr *iph = zbuf_pull(zb, struct ipv6hdr); if (iph) { if (src) sockunion_set(src, AF_INET6, (uint8_t *)&iph->saddr, sizeof(iph->saddr)); if (dst) sockunion_set(dst, AF_INET6, (uint8_t *)&iph->daddr, sizeof(iph->daddr)); } } break; default: return 0; } return 1; } void nhrp_peer_send_indication(struct interface *ifp, uint16_t protocol_type, struct zbuf *pkt) { union sockunion dst; struct zbuf *zb, payload; struct nhrp_interface *nifp = ifp->info; struct nhrp_afi_data *if_ad; struct nhrp_packet_header *hdr; struct nhrp_peer *p; if (!nifp->enabled) return; payload = *pkt; if (!parse_ether_packet(&payload, protocol_type, &dst, NULL)) return; if (nhrp_route_address(ifp, &dst, NULL, &p) != NHRP_ROUTE_NBMA_NEXTHOP) return; if_ad = &nifp->afi[family2afi(sockunion_family(&dst))]; if (!(if_ad->flags & NHRP_IFF_REDIRECT)) { debugf(NHRP_DEBUG_COMMON, "Send Traffic Indication to %pSU about packet to %pSU ignored", &p->vc->remote.nbma, &dst); return; } debugf(NHRP_DEBUG_COMMON, "Send Traffic Indication to %pSU (online=%d) about packet to %pSU", &p->vc->remote.nbma, p->online, &dst); /* Create reply */ zb = zbuf_alloc(1500); hdr = nhrp_packet_push(zb, NHRP_PACKET_TRAFFIC_INDICATION, &nifp->nbma, &if_ad->addr, &dst); hdr->hop_count = 1; /* Payload is the packet causing indication */ zbuf_copy(zb, pkt, zbuf_used(pkt)); nhrp_packet_complete(zb, hdr); nhrp_peer_send(p, zb); nhrp_peer_unref(p); zbuf_free(zb); } static void nhrp_handle_error_ind(struct nhrp_packet_parser *pp) { struct zbuf origmsg = pp->payload; struct nhrp_packet_header *hdr; struct nhrp_reqid *reqid; union sockunion src_nbma, src_proto, dst_proto; hdr = nhrp_packet_pull(&origmsg, &src_nbma, &src_proto, &dst_proto); if (!hdr) return; debugf(NHRP_DEBUG_COMMON, "Error Indication from %pSU about packet to %pSU ignored", &pp->src_proto, &dst_proto); reqid = nhrp_reqid_lookup(&nhrp_packet_reqid, htonl(hdr->u.request_id)); if (reqid) reqid->cb(reqid, pp); } static void nhrp_handle_traffic_ind(struct nhrp_packet_parser *p) { union sockunion dst; if (!parse_ether_packet(&p->payload, htons(p->hdr->protocol_type), NULL, &dst)) return; debugf(NHRP_DEBUG_COMMON, "Traffic Indication from %pSU about packet to %pSU: %s", &p->src_proto, &dst, (p->if_ad->flags & NHRP_IFF_SHORTCUT) ? "trying shortcut" : "ignored"); if (p->if_ad->flags & NHRP_IFF_SHORTCUT) nhrp_shortcut_initiate(&dst); } enum packet_type_t { PACKET_UNKNOWN = 0, PACKET_REQUEST, PACKET_REPLY, PACKET_INDICATION, }; static struct { enum packet_type_t type; const char *name; void (*handler)(struct nhrp_packet_parser *); } packet_types[] = {[0] = { .type = PACKET_UNKNOWN, .name = "UNKNOWN", }, [NHRP_PACKET_RESOLUTION_REQUEST] = { .type = PACKET_REQUEST, .name = "Resolution-Request", .handler = nhrp_handle_resolution_req, }, [NHRP_PACKET_RESOLUTION_REPLY] = { .type = PACKET_REPLY, .name = "Resolution-Reply", }, [NHRP_PACKET_REGISTRATION_REQUEST] = { .type = PACKET_REQUEST, .name = "Registration-Request", .handler = nhrp_handle_registration_request, }, [NHRP_PACKET_REGISTRATION_REPLY] = { .type = PACKET_REPLY, .name = "Registration-Reply", }, [NHRP_PACKET_PURGE_REQUEST] = { .type = PACKET_REQUEST, .name = "Purge-Request", }, [NHRP_PACKET_PURGE_REPLY] = { .type = PACKET_REPLY, .name = "Purge-Reply", }, [NHRP_PACKET_ERROR_INDICATION] = { .type = PACKET_INDICATION, .name = "Error-Indication", .handler = nhrp_handle_error_ind, }, [NHRP_PACKET_TRAFFIC_INDICATION] = { .type = PACKET_INDICATION, .name = "Traffic-Indication", .handler = nhrp_handle_traffic_ind, }}; static void nhrp_peer_forward(struct nhrp_peer *p, struct nhrp_packet_parser *pp) { struct zbuf *zb, *zb_copy, extpl; struct nhrp_packet_header *hdr; struct nhrp_extension_header *ext, *dst; struct nhrp_cie_header *cie; struct nhrp_interface *nifp = pp->ifp->info; struct nhrp_afi_data *if_ad = pp->if_ad; union sockunion cie_nbma, cie_protocol, cie_protocol_mandatory, *proto; uint16_t type, len; struct nhrp_cache *c; if (pp->hdr->hop_count == 0) return; /* Create forward packet - copy header */ zb = zbuf_alloc(1500); zb_copy = zbuf_alloc(1500); hdr = nhrp_packet_push(zb, pp->hdr->type, &pp->src_nbma, &pp->src_proto, &pp->dst_proto); hdr->flags = pp->hdr->flags; hdr->hop_count = pp->hdr->hop_count - 1; hdr->u.request_id = pp->hdr->u.request_id; /* Copy payload */ zbuf_copy_peek(zb_copy, &pp->payload, zbuf_used(&pp->payload)); zbuf_copy(zb, &pp->payload, zbuf_used(&pp->payload)); /* Get CIE Extension from Mandatory part */ sockunion_family(&cie_protocol_mandatory) = AF_UNSPEC; nhrp_cie_pull(zb_copy, pp->hdr, &cie_nbma, &cie_protocol_mandatory); /* Copy extensions */ while ((ext = nhrp_ext_pull(&pp->extensions, &extpl)) != NULL) { type = htons(ext->type) & ~NHRP_EXTENSION_FLAG_COMPULSORY; len = htons(ext->length); if (type == NHRP_EXTENSION_END) break; dst = nhrp_ext_push(zb, hdr, htons(ext->type)); if (!dst) goto err; switch (type) { case NHRP_EXTENSION_FORWARD_TRANSIT_NHS: case NHRP_EXTENSION_REVERSE_TRANSIT_NHS: zbuf_put(zb, extpl.head, len); if ((type == NHRP_EXTENSION_REVERSE_TRANSIT_NHS) == (packet_types[hdr->type].type == PACKET_REPLY)) { /* Check NHS list for forwarding loop */ while (nhrp_cie_pull(&extpl, pp->hdr, &cie_nbma, &cie_protocol) != NULL) { if (sockunion_same(&p->vc->remote.nbma, &cie_nbma)) goto err; } /* Append our selves to the list */ cie = nhrp_cie_push(zb, NHRP_CODE_SUCCESS, &nifp->nbma, &if_ad->addr); if (!cie) goto err; cie->mtu = htons(if_ad->mtu); cie->holding_time = htons(if_ad->holdtime); } break; case NHRP_EXTENSION_NAT_ADDRESS: c = NULL; proto = NULL; /* If NAT extension is empty then attempt to populate * it with cached NBMA information */ if (len == 0) { if (packet_types[hdr->type].type == PACKET_REQUEST) { debugf(NHRP_DEBUG_COMMON, "Processing NHRP_EXTENSION_NAT_ADDRESS while forwarding the request packet"); proto = &pp->src_proto; } else if (packet_types[hdr->type].type == PACKET_REPLY) { debugf(NHRP_DEBUG_COMMON, "Processing NHRP_EXTENSION_NAT_ADDRESS while forwarding the reply packet"); /* For reply packet use protocol * specified in CIE of mandatory part * for cache lookup */ if (sockunion_family( &cie_protocol_mandatory) != AF_UNSPEC) proto = &cie_protocol_mandatory; } } if (proto) { debugf(NHRP_DEBUG_COMMON, "Proto is %pSU", proto); c = nhrp_cache_get(nifp->ifp, proto, 0); } if (c) { debugf(NHRP_DEBUG_COMMON, "c->cur.remote_nbma_natoa is %pSU", &c->cur.remote_nbma_natoa); if (sockunion_family(&c->cur.remote_nbma_natoa) != AF_UNSPEC) { cie = nhrp_cie_push( zb, NHRP_CODE_SUCCESS, &c->cur.remote_nbma_natoa, proto); if (!cie) goto err; } } else { if (proto) debugf(NHRP_DEBUG_COMMON, "No cache entry for proto %pSU", proto); /* Copy existing NAT extension to new packet if * either it was already not-empty, or we do not * have valid cache information */ zbuf_put(zb, extpl.head, len); } break; default: if (htons(ext->type) & NHRP_EXTENSION_FLAG_COMPULSORY) /* FIXME: RFC says to just copy, but not * append our selves to the transit NHS list */ goto err; fallthrough; case NHRP_EXTENSION_RESPONDER_ADDRESS: /* Supported compulsory extensions, and any * non-compulsory that is not explicitly handled, * should be just copied. */ zbuf_copy(zb, &extpl, len); break; } nhrp_ext_complete(zb, dst); } nhrp_packet_complete(zb, hdr); nhrp_peer_send(p, zb); zbuf_free(zb); zbuf_free(zb_copy); return; err: nhrp_packet_debug(pp->pkt, "FWD-FAIL"); zbuf_free(zb); zbuf_free(zb_copy); } static void nhrp_packet_debug(struct zbuf *zb, const char *dir) { union sockunion src_nbma, src_proto, dst_proto; struct nhrp_packet_header *hdr; struct zbuf zhdr; int reply; if (likely(!(debug_flags & NHRP_DEBUG_COMMON))) return; zbuf_init(&zhdr, zb->buf, zb->tail - zb->buf, zb->tail - zb->buf); hdr = nhrp_packet_pull(&zhdr, &src_nbma, &src_proto, &dst_proto); reply = packet_types[hdr->type].type == PACKET_REPLY; debugf(NHRP_DEBUG_COMMON, "%s %s(%d) %pSU -> %pSU", dir, (packet_types[hdr->type].name ? packet_types[hdr->type].name : "Unknown"), hdr->type, reply ? &dst_proto : &src_proto, reply ? &src_proto : &dst_proto); } static int proto2afi(uint16_t proto) { switch (proto) { case ETH_P_IP: return AFI_IP; case ETH_P_IPV6: return AFI_IP6; } return AF_UNSPEC; } struct nhrp_route_info { int local; struct interface *ifp; struct nhrp_vc *vc; }; void nhrp_peer_recv(struct nhrp_peer *p, struct zbuf *zb) { struct nhrp_packet_header *hdr; struct nhrp_vc *vc = p->vc; struct interface *ifp = p->ifp; struct nhrp_interface *nifp = ifp->info; struct nhrp_packet_parser pp; struct nhrp_peer *peer = NULL; struct nhrp_reqid *reqid; const char *info = NULL; union sockunion *target_addr; unsigned paylen, extoff, extlen, realsize; afi_t nbma_afi, proto_afi; debugf(NHRP_DEBUG_KERNEL, "PACKET: Recv %pSU -> %pSU", &vc->remote.nbma, &vc->local.nbma); if (!p->online) { info = "peer not online"; goto drop; } if (nhrp_packet_calculate_checksum(zb->head, zbuf_used(zb)) != 0) { info = "bad checksum"; goto drop; } realsize = zbuf_used(zb); hdr = nhrp_packet_pull(zb, &pp.src_nbma, &pp.src_proto, &pp.dst_proto); if (!hdr) { info = "corrupt header"; goto drop; } pp.ifp = ifp; pp.pkt = zb; pp.hdr = hdr; pp.peer = p; nbma_afi = htons(hdr->afnum); proto_afi = proto2afi(htons(hdr->protocol_type)); if (hdr->type > NHRP_PACKET_MAX || hdr->version != NHRP_VERSION_RFC2332 || nbma_afi >= AFI_MAX || proto_afi == AF_UNSPEC || packet_types[hdr->type].type == PACKET_UNKNOWN || htons(hdr->packet_size) > realsize) { zlog_info( "From %pSU: error: packet type %d, version %d, AFI %d, proto %x, size %d (real size %d)", &vc->remote.nbma, (int)hdr->type, (int)hdr->version, (int)nbma_afi, (int)htons(hdr->protocol_type), (int)htons(hdr->packet_size), (int)realsize); goto drop; } pp.if_ad = &((struct nhrp_interface *)ifp->info)->afi[proto_afi]; extoff = htons(hdr->extension_offset); if (extoff) { assert(zb->head > zb->buf); uint32_t header_offset = zb->head - zb->buf; if (extoff >= realsize) { info = "extoff larger than packet"; goto drop; } if (extoff < header_offset) { info = "extoff smaller than header offset"; goto drop; } paylen = extoff - header_offset; } else { paylen = zbuf_used(zb); } zbuf_init(&pp.payload, zbuf_pulln(zb, paylen), paylen, paylen); extlen = zbuf_used(zb); zbuf_init(&pp.extensions, zbuf_pulln(zb, extlen), extlen, extlen); if (!nifp->afi[proto_afi].network_id) { info = "nhrp not enabled"; goto drop; } nhrp_packet_debug(zb, "Recv"); /* FIXME: Check authentication here. This extension needs to be * pre-handled. */ /* Figure out if this is local */ target_addr = (packet_types[hdr->type].type == PACKET_REPLY) ? &pp.src_proto : &pp.dst_proto; if (sockunion_same(&pp.src_proto, &pp.dst_proto)) pp.route_type = NHRP_ROUTE_LOCAL; else pp.route_type = nhrp_route_address(pp.ifp, target_addr, &pp.route_prefix, &peer); switch (pp.route_type) { case NHRP_ROUTE_LOCAL: nhrp_packet_debug(zb, "!LOCAL"); if (packet_types[hdr->type].type == PACKET_REPLY) { reqid = nhrp_reqid_lookup(&nhrp_packet_reqid, htonl(hdr->u.request_id)); if (reqid) { reqid->cb(reqid, &pp); break; } else { nhrp_packet_debug(zb, "!UNKNOWN-REQID"); /* FIXME: send error-indication */ } } fallthrough; /* FIXME: double check, is this correct? */ case NHRP_ROUTE_OFF_NBMA: if (packet_types[hdr->type].handler) { packet_types[hdr->type].handler(&pp); break; } break; case NHRP_ROUTE_NBMA_NEXTHOP: nhrp_peer_forward(peer, &pp); break; case NHRP_ROUTE_BLACKHOLE: break; } drop: if (info) { zlog_info("From %pSU: error: %s", &vc->remote.nbma, info); } if (peer) nhrp_peer_unref(peer); zbuf_free(zb); }