/* SPDX-License-Identifier: LGPL-2.1-or-later */ #include "alloc-util.h" #include "hashmap.h" #include "netlink-util.h" #include "networkd-link.h" #include "networkd-manager.h" #include "networkd-neighbor.h" #include "networkd-network.h" #include "networkd-queue.h" #include "set.h" Neighbor *neighbor_free(Neighbor *neighbor) { if (!neighbor) return NULL; if (neighbor->network) { assert(neighbor->section); ordered_hashmap_remove(neighbor->network->neighbors_by_section, neighbor->section); } config_section_free(neighbor->section); if (neighbor->link) set_remove(neighbor->link->neighbors, neighbor); return mfree(neighbor); } DEFINE_SECTION_CLEANUP_FUNCTIONS(Neighbor, neighbor_free); static int neighbor_new_static(Network *network, const char *filename, unsigned section_line, Neighbor **ret) { _cleanup_(config_section_freep) ConfigSection *n = NULL; _cleanup_(neighbor_freep) Neighbor *neighbor = NULL; int r; assert(network); assert(ret); assert(filename); assert(section_line > 0); r = config_section_new(filename, section_line, &n); if (r < 0) return r; neighbor = ordered_hashmap_get(network->neighbors_by_section, n); if (neighbor) { *ret = TAKE_PTR(neighbor); return 0; } neighbor = new(Neighbor, 1); if (!neighbor) return -ENOMEM; *neighbor = (Neighbor) { .network = network, .family = AF_UNSPEC, .section = TAKE_PTR(n), .source = NETWORK_CONFIG_SOURCE_STATIC, }; r = ordered_hashmap_ensure_put(&network->neighbors_by_section, &config_section_hash_ops, neighbor->section, neighbor); if (r < 0) return r; *ret = TAKE_PTR(neighbor); return 0; } static int neighbor_dup(const Neighbor *neighbor, Neighbor **ret) { _cleanup_(neighbor_freep) Neighbor *dest = NULL; assert(neighbor); assert(ret); dest = newdup(Neighbor, neighbor, 1); if (!dest) return -ENOMEM; /* Unset all pointers */ dest->link = NULL; dest->network = NULL; dest->section = NULL; *ret = TAKE_PTR(dest); return 0; } static void neighbor_hash_func(const Neighbor *neighbor, struct siphash *state) { assert(neighbor); siphash24_compress(&neighbor->family, sizeof(neighbor->family), state); if (!IN_SET(neighbor->family, AF_INET, AF_INET6)) /* treat any other address family as AF_UNSPEC */ return; /* Equality of neighbors are given by the destination address. * See neigh_lookup() in the kernel. */ siphash24_compress(&neighbor->in_addr, FAMILY_ADDRESS_SIZE(neighbor->family), state); } static int neighbor_compare_func(const Neighbor *a, const Neighbor *b) { int r; r = CMP(a->family, b->family); if (r != 0) return r; if (!IN_SET(a->family, AF_INET, AF_INET6)) /* treat any other address family as AF_UNSPEC */ return 0; return memcmp(&a->in_addr, &b->in_addr, FAMILY_ADDRESS_SIZE(a->family)); } DEFINE_PRIVATE_HASH_OPS( neighbor_hash_ops, Neighbor, neighbor_hash_func, neighbor_compare_func); DEFINE_PRIVATE_HASH_OPS_WITH_KEY_DESTRUCTOR( neighbor_hash_ops_free, Neighbor, neighbor_hash_func, neighbor_compare_func, neighbor_free); static int neighbor_get_request(Link *link, const Neighbor *neighbor, Request **ret) { Request *req; assert(link); assert(link->manager); assert(neighbor); req = ordered_set_get( link->manager->request_queue, &(Request) { .link = link, .type = REQUEST_TYPE_NEIGHBOR, .userdata = (void*) neighbor, .hash_func = (hash_func_t) neighbor_hash_func, .compare_func = (compare_func_t) neighbor_compare_func, }); if (!req) return -ENOENT; if (ret) *ret = req; return 0; } static int neighbor_get(Link *link, const Neighbor *in, Neighbor **ret) { Neighbor *existing; assert(link); assert(in); existing = set_get(link->neighbors, in); if (!existing) return -ENOENT; if (ret) *ret = existing; return 0; } static int neighbor_add(Link *link, Neighbor *neighbor) { int r; assert(link); assert(neighbor); r = set_ensure_put(&link->neighbors, &neighbor_hash_ops_free, neighbor); if (r < 0) return r; if (r == 0) return -EEXIST; neighbor->link = link; return 0; } static void log_neighbor_debug(const Neighbor *neighbor, const char *str, const Link *link) { _cleanup_free_ char *state = NULL; assert(neighbor); assert(str); if (!DEBUG_LOGGING) return; (void) network_config_state_to_string_alloc(neighbor->state, &state); log_link_debug(link, "%s %s neighbor (%s): lladdr: %s, dst: %s", str, strna(network_config_source_to_string(neighbor->source)), strna(state), HW_ADDR_TO_STR(&neighbor->ll_addr), IN_ADDR_TO_STRING(neighbor->family, &neighbor->in_addr)); } static int neighbor_configure(Neighbor *neighbor, Link *link, Request *req) { _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL; int r; assert(neighbor); assert(link); assert(link->ifindex > 0); assert(link->manager); assert(link->manager->rtnl); assert(req); log_neighbor_debug(neighbor, "Configuring", link); r = sd_rtnl_message_new_neigh(link->manager->rtnl, &m, RTM_NEWNEIGH, link->ifindex, neighbor->family); if (r < 0) return r; r = sd_rtnl_message_neigh_set_state(m, NUD_PERMANENT); if (r < 0) return r; r = netlink_message_append_hw_addr(m, NDA_LLADDR, &neighbor->ll_addr); if (r < 0) return r; r = netlink_message_append_in_addr_union(m, NDA_DST, neighbor->family, &neighbor->in_addr); if (r < 0) return r; return request_call_netlink_async(link->manager->rtnl, m, req); } static int neighbor_process_request(Request *req, Link *link, Neighbor *neighbor) { Neighbor *existing; int r; assert(req); assert(link); assert(neighbor); if (!link_is_ready_to_configure(link, false)) return 0; r = neighbor_configure(neighbor, link, req); if (r < 0) return log_link_warning_errno(link, r, "Failed to configure neighbor: %m"); neighbor_enter_configuring(neighbor); if (neighbor_get(link, neighbor, &existing) >= 0) neighbor_enter_configuring(existing); return 1; } static int static_neighbor_configure_handler(sd_netlink *rtnl, sd_netlink_message *m, Request *req, Link *link, Neighbor *neighbor) { int r; assert(m); assert(link); r = sd_netlink_message_get_errno(m); if (r < 0 && r != -EEXIST) { log_link_message_warning_errno(link, m, r, "Could not set neighbor"); link_enter_failed(link); return 1; } if (link->static_neighbor_messages == 0) { log_link_debug(link, "Neighbors set"); link->static_neighbors_configured = true; link_check_ready(link); } return 1; } static int link_request_neighbor(Link *link, const Neighbor *neighbor) { _cleanup_(neighbor_freep) Neighbor *tmp = NULL; Neighbor *existing = NULL; int r; assert(link); assert(neighbor); assert(neighbor->source != NETWORK_CONFIG_SOURCE_FOREIGN); if (neighbor->ll_addr.length != link->hw_addr.length) { log_link_debug(link, "The link layer address length (%zu) for neighbor %s does not match with " "the hardware address length (%zu), ignoring the setting.", neighbor->ll_addr.length, IN_ADDR_TO_STRING(neighbor->family, &neighbor->in_addr), link->hw_addr.length); return 0; } r = neighbor_dup(neighbor, &tmp); if (r < 0) return r; if (neighbor_get(link, neighbor, &existing) >= 0) /* Copy state for logging below. */ tmp->state = existing->state; log_neighbor_debug(tmp, "Requesting", link); r = link_queue_request_safe(link, REQUEST_TYPE_NEIGHBOR, tmp, neighbor_free, neighbor_hash_func, neighbor_compare_func, neighbor_process_request, &link->static_neighbor_messages, static_neighbor_configure_handler, NULL); if (r <= 0) return r; neighbor_enter_requesting(tmp); if (existing) neighbor_enter_requesting(existing); TAKE_PTR(tmp); return 1; } int link_request_static_neighbors(Link *link) { Neighbor *neighbor; int r; assert(link); assert(link->network); assert(link->state != _LINK_STATE_INVALID); link->static_neighbors_configured = false; ORDERED_HASHMAP_FOREACH(neighbor, link->network->neighbors_by_section) { r = link_request_neighbor(link, neighbor); if (r < 0) return log_link_warning_errno(link, r, "Could not request neighbor: %m"); } if (link->static_neighbor_messages == 0) { link->static_neighbors_configured = true; link_check_ready(link); } else { log_link_debug(link, "Requesting neighbors"); link_set_state(link, LINK_STATE_CONFIGURING); } return 0; } static int neighbor_remove_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) { int r; assert(m); assert(link); if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER)) return 1; r = sd_netlink_message_get_errno(m); if (r < 0 && r != -ESRCH) /* Neighbor may not exist because it already got deleted, ignore that. */ log_link_message_warning_errno(link, m, r, "Could not remove neighbor"); return 1; } static int neighbor_remove(Neighbor *neighbor) { _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL; Request *req; Link *link; int r; assert(neighbor); assert(neighbor->link); assert(neighbor->link->manager); assert(neighbor->link->manager->rtnl); link = neighbor->link; log_neighbor_debug(neighbor, "Removing", link); r = sd_rtnl_message_new_neigh(link->manager->rtnl, &m, RTM_DELNEIGH, link->ifindex, neighbor->family); if (r < 0) return log_link_error_errno(link, r, "Could not allocate RTM_DELNEIGH message: %m"); r = netlink_message_append_in_addr_union(m, NDA_DST, neighbor->family, &neighbor->in_addr); if (r < 0) return log_link_error_errno(link, r, "Could not append NDA_DST attribute: %m"); r = netlink_call_async(link->manager->rtnl, NULL, m, neighbor_remove_handler, link_netlink_destroy_callback, link); if (r < 0) return log_link_error_errno(link, r, "Could not send rtnetlink message: %m"); link_ref(link); neighbor_enter_removing(neighbor); if (neighbor_get_request(neighbor->link, neighbor, &req) >= 0) neighbor_enter_removing(req->userdata); return 0; } int link_drop_foreign_neighbors(Link *link) { Neighbor *neighbor; int r = 0; assert(link); assert(link->network); /* First, mark all neighbors. */ SET_FOREACH(neighbor, link->neighbors) { /* Do not remove neighbors we configured. */ if (neighbor->source != NETWORK_CONFIG_SOURCE_FOREIGN) continue; /* Ignore neighbors not assigned yet or already removing. */ if (!neighbor_exists(neighbor)) continue; neighbor_mark(neighbor); } /* Next, unmark requested neighbors. They will be configured later. */ ORDERED_HASHMAP_FOREACH(neighbor, link->network->neighbors_by_section) { Neighbor *existing; if (neighbor_get(link, neighbor, &existing) >= 0) neighbor_unmark(existing); } SET_FOREACH(neighbor, link->neighbors) { if (!neighbor_is_marked(neighbor)) continue; RET_GATHER(r, neighbor_remove(neighbor)); } return r; } int link_drop_managed_neighbors(Link *link) { Neighbor *neighbor; int r = 0; assert(link); SET_FOREACH(neighbor, link->neighbors) { /* Do not touch nexthops managed by kernel or other tools. */ if (neighbor->source == NETWORK_CONFIG_SOURCE_FOREIGN) continue; /* Ignore neighbors not assigned yet or already removing. */ if (!neighbor_exists(neighbor)) continue; RET_GATHER(r, neighbor_remove(neighbor)); } return r; } void link_foreignize_neighbors(Link *link) { Neighbor *neighbor; assert(link); SET_FOREACH(neighbor, link->neighbors) neighbor->source = NETWORK_CONFIG_SOURCE_FOREIGN; } int manager_rtnl_process_neighbor(sd_netlink *rtnl, sd_netlink_message *message, Manager *m) { _cleanup_(neighbor_freep) Neighbor *tmp = NULL; Neighbor *neighbor = NULL; Request *req = NULL; uint16_t type, state; bool is_new = false; int ifindex, r; Link *link; assert(rtnl); assert(message); assert(m); if (sd_netlink_message_is_error(message)) { r = sd_netlink_message_get_errno(message); if (r < 0) log_message_warning_errno(message, r, "rtnl: failed to receive neighbor message, ignoring"); return 0; } r = sd_netlink_message_get_type(message, &type); if (r < 0) { log_warning_errno(r, "rtnl: could not get message type, ignoring: %m"); return 0; } else if (!IN_SET(type, RTM_NEWNEIGH, RTM_DELNEIGH)) { log_warning("rtnl: received unexpected message type %u when processing neighbor, ignoring.", type); return 0; } r = sd_rtnl_message_neigh_get_state(message, &state); if (r < 0) { log_warning_errno(r, "rtnl: received neighbor message with invalid state, ignoring: %m"); return 0; } else if (!FLAGS_SET(state, NUD_PERMANENT)) { log_debug("rtnl: received non-static neighbor, ignoring."); return 0; } r = sd_rtnl_message_neigh_get_ifindex(message, &ifindex); if (r < 0) { log_warning_errno(r, "rtnl: could not get ifindex from message, ignoring: %m"); return 0; } else if (ifindex <= 0) { log_warning("rtnl: received neighbor message with invalid ifindex %d, ignoring.", ifindex); return 0; } r = link_get_by_index(m, ifindex, &link); if (r < 0) { /* when enumerating we might be out of sync, but we will get the neighbor again. Also, * kernel sends messages about neighbors after a link is removed. So, just ignore it. */ log_debug("rtnl: received neighbor for link '%d' we don't know about, ignoring.", ifindex); return 0; } tmp = new0(Neighbor, 1); if (!tmp) return log_oom(); /* First, retrieve the fundamental information about the neighbor. */ r = sd_rtnl_message_neigh_get_family(message, &tmp->family); if (r < 0) { log_link_warning(link, "rtnl: received neighbor message without family, ignoring."); return 0; } else if (!IN_SET(tmp->family, AF_INET, AF_INET6)) { log_link_debug(link, "rtnl: received neighbor message with invalid family '%i', ignoring.", tmp->family); return 0; } r = netlink_message_read_in_addr_union(message, NDA_DST, tmp->family, &tmp->in_addr); if (r < 0) { log_link_warning_errno(link, r, "rtnl: received neighbor message without valid address, ignoring: %m"); return 0; } /* Then, find the managed Neighbor and Request objects corresponding to the netlink notification. */ (void) neighbor_get(link, tmp, &neighbor); (void) neighbor_get_request(link, tmp, &req); if (type == RTM_DELNEIGH) { if (neighbor) { neighbor_enter_removed(neighbor); log_neighbor_debug(neighbor, "Forgetting removed", link); neighbor_free(neighbor); } else log_neighbor_debug(tmp, "Kernel removed unknown", link); if (req) neighbor_enter_removed(req->userdata); return 0; } /* If we did not know the neighbor, then save it. */ if (!neighbor) { r = neighbor_add(link, tmp); if (r < 0) { log_link_warning_errno(link, r, "Failed to save received neighbor, ignoring: %m"); return 0; } neighbor = TAKE_PTR(tmp); is_new = true; } /* Also update information that cannot be obtained through netlink notification. */ if (req && req->waiting_reply) { Neighbor *n = ASSERT_PTR(req->userdata); neighbor->source = n->source; } /* Then, update miscellaneous info. */ r = netlink_message_read_hw_addr(message, NDA_LLADDR, &neighbor->ll_addr); if (r < 0 && r != -ENODATA) log_link_debug_errno(link, r, "rtnl: received neighbor message without valid link layer address, ignoring: %m"); neighbor_enter_configured(neighbor); if (req) neighbor_enter_configured(req->userdata); log_neighbor_debug(neighbor, is_new ? "Remembering" : "Received remembered", link); return 1; } static int neighbor_section_verify(Neighbor *neighbor) { if (section_is_invalid(neighbor->section)) return -EINVAL; if (neighbor->family == AF_UNSPEC) return log_warning_errno(SYNTHETIC_ERRNO(EINVAL), "%s: Neighbor section without Address= configured. " "Ignoring [Neighbor] section from line %u.", neighbor->section->filename, neighbor->section->line); if (neighbor->family == AF_INET6 && !socket_ipv6_is_supported()) return log_warning_errno(SYNTHETIC_ERRNO(EINVAL), "%s: Neighbor section with an IPv6 destination address configured, " "but the kernel does not support IPv6. " "Ignoring [Neighbor] section from line %u.", neighbor->section->filename, neighbor->section->line); if (neighbor->ll_addr.length == 0) return log_warning_errno(SYNTHETIC_ERRNO(EINVAL), "%s: Neighbor section without LinkLayerAddress= configured. " "Ignoring [Neighbor] section from line %u.", neighbor->section->filename, neighbor->section->line); return 0; } int network_drop_invalid_neighbors(Network *network) { _cleanup_set_free_ Set *neighbors = NULL; Neighbor *neighbor; int r; assert(network); ORDERED_HASHMAP_FOREACH(neighbor, network->neighbors_by_section) { Neighbor *dup; if (neighbor_section_verify(neighbor) < 0) { /* Drop invalid [Neighbor] sections. Note that neighbor_free() will drop the * neighbor from neighbors_by_section. */ neighbor_free(neighbor); continue; } /* Always use the setting specified later. So, remove the previously assigned setting. */ dup = set_remove(neighbors, neighbor); if (dup) { log_warning("%s: Duplicated neighbor settings for %s is specified at line %u and %u, " "dropping the address setting specified at line %u.", dup->section->filename, IN_ADDR_TO_STRING(neighbor->family, &neighbor->in_addr), neighbor->section->line, dup->section->line, dup->section->line); /* neighbor_free() will drop the address from neighbors_by_section. */ neighbor_free(dup); } /* Use neighbor_hash_ops, instead of neighbor_hash_ops_free. Otherwise, the Neighbor objects * will be freed. */ r = set_ensure_put(&neighbors, &neighbor_hash_ops, neighbor); if (r < 0) return log_oom(); assert(r > 0); } return 0; } int config_parse_neighbor_address( const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata) { _cleanup_(neighbor_free_or_set_invalidp) Neighbor *n = NULL; Network *network = ASSERT_PTR(userdata); int r; assert(filename); assert(section); assert(lvalue); assert(rvalue); r = neighbor_new_static(network, filename, section_line, &n); if (r < 0) return log_oom(); if (isempty(rvalue)) { n->family = AF_UNSPEC; n->in_addr = IN_ADDR_NULL; TAKE_PTR(n); return 0; } r = in_addr_from_string_auto(rvalue, &n->family, &n->in_addr); if (r < 0) { log_syntax(unit, LOG_WARNING, filename, line, r, "Neighbor Address is invalid, ignoring assignment: %s", rvalue); return 0; } TAKE_PTR(n); return 0; } int config_parse_neighbor_lladdr( const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata) { _cleanup_(neighbor_free_or_set_invalidp) Neighbor *n = NULL; Network *network = ASSERT_PTR(userdata); int r; assert(filename); assert(section); assert(lvalue); assert(rvalue); r = neighbor_new_static(network, filename, section_line, &n); if (r < 0) return log_oom(); if (isempty(rvalue)) { n->ll_addr = HW_ADDR_NULL; TAKE_PTR(n); return 0; } r = parse_hw_addr(rvalue, &n->ll_addr); if (r < 0) { log_syntax(unit, LOG_WARNING, filename, line, r, "Neighbor %s= is invalid, ignoring assignment: %s", lvalue, rvalue); return 0; } TAKE_PTR(n); return 0; }