/* SPDX-License-Identifier: LGPL-2.1-or-later */ /*** Copyright © 2014 Intel Corporation. All rights reserved. ***/ #include #include #include #include "sd-ndisc.h" #include "missing_network.h" #include "networkd-address-generation.h" #include "networkd-address.h" #include "networkd-dhcp6.h" #include "networkd-manager.h" #include "networkd-ndisc.h" #include "networkd-queue.h" #include "networkd-route.h" #include "networkd-state-file.h" #include "string-table.h" #include "string-util.h" #include "strv.h" #define NDISC_DNSSL_MAX 64U #define NDISC_RDNSS_MAX 64U bool link_ipv6_accept_ra_enabled(Link *link) { assert(link); if (!socket_ipv6_is_supported()) return false; if (link->flags & IFF_LOOPBACK) return false; if (!link->network) return false; if (!link_may_have_ipv6ll(link)) return false; assert(link->network->ipv6_accept_ra >= 0); return link->network->ipv6_accept_ra; } void network_adjust_ipv6_accept_ra(Network *network) { assert(network); if (!FLAGS_SET(network->link_local, ADDRESS_FAMILY_IPV6)) { if (network->ipv6_accept_ra > 0) log_warning("%s: IPv6AcceptRA= is enabled but IPv6 link local addressing is disabled or not supported. " "Disabling IPv6AcceptRA=.", network->filename); network->ipv6_accept_ra = false; } if (network->ipv6_accept_ra < 0) /* default to accept RA if ip_forward is disabled and ignore RA if ip_forward is enabled */ network->ipv6_accept_ra = !FLAGS_SET(network->ip_forward, ADDRESS_FAMILY_IPV6); /* When RouterAllowList=, PrefixAllowList= or RouteAllowList= are specified, then * RouterDenyList=, PrefixDenyList= or RouteDenyList= are ignored, respectively. */ if (!set_isempty(network->ndisc_allow_listed_router)) network->ndisc_deny_listed_router = set_free_free(network->ndisc_deny_listed_router); if (!set_isempty(network->ndisc_allow_listed_prefix)) network->ndisc_deny_listed_prefix = set_free_free(network->ndisc_deny_listed_prefix); if (!set_isempty(network->ndisc_allow_listed_route_prefix)) network->ndisc_deny_listed_route_prefix = set_free_free(network->ndisc_deny_listed_route_prefix); } static int ndisc_remove(Link *link, struct in6_addr *router) { bool updated = false; NDiscDNSSL *dnssl; NDiscRDNSS *rdnss; Address *address; Route *route; int k, r = 0; assert(link); SET_FOREACH(route, link->routes) { if (route->source != NETWORK_CONFIG_SOURCE_NDISC) continue; if (!route_is_marked(route)) continue; if (router && !in6_addr_equal(router, &route->provider.in6)) continue; k = route_remove(route); if (k < 0) r = k; route_cancel_request(route, link); } SET_FOREACH(address, link->addresses) { if (address->source != NETWORK_CONFIG_SOURCE_NDISC) continue; if (!address_is_marked(address)) continue; if (router && !in6_addr_equal(router, &address->provider.in6)) continue; k = address_remove(address); if (k < 0) r = k; address_cancel_request(address); } SET_FOREACH(rdnss, link->ndisc_rdnss) { if (!rdnss->marked) continue; if (router && !in6_addr_equal(router, &rdnss->router)) continue; free(set_remove(link->ndisc_rdnss, rdnss)); updated = true; } SET_FOREACH(dnssl, link->ndisc_dnssl) { if (!dnssl->marked) continue; if (router && !in6_addr_equal(router, &dnssl->router)) continue; free(set_remove(link->ndisc_dnssl, dnssl)); updated = true; } if (updated) link_dirty(link); return r; } static int ndisc_check_ready(Link *link); static int ndisc_address_ready_callback(Address *address) { Address *a; assert(address); assert(address->link); SET_FOREACH(a, address->link->addresses) if (a->source == NETWORK_CONFIG_SOURCE_NDISC) a->callback = NULL; return ndisc_check_ready(address->link); } static int ndisc_check_ready(Link *link) { bool found = false, ready = false; Address *address; int r; assert(link); if (link->ndisc_messages > 0) { log_link_debug(link, "%s(): SLAAC addresses and routes are not set.", __func__); return 0; } SET_FOREACH(address, link->addresses) { if (address->source != NETWORK_CONFIG_SOURCE_NDISC) continue; found = true; if (address_is_ready(address)) { ready = true; break; } } if (found && !ready) { SET_FOREACH(address, link->addresses) if (address->source == NETWORK_CONFIG_SOURCE_NDISC) address->callback = ndisc_address_ready_callback; log_link_debug(link, "%s(): no SLAAC address is ready.", __func__); return 0; } link->ndisc_configured = true; log_link_debug(link, "SLAAC addresses and routes set."); r = ndisc_remove(link, NULL); if (r < 0) return r; link_check_ready(link); return 0; } static int ndisc_route_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) { int r; assert(link); assert(link->ndisc_messages > 0); link->ndisc_messages--; r = route_configure_handler_internal(rtnl, m, link, "Could not set NDisc route"); if (r <= 0) return r; r = ndisc_check_ready(link); if (r < 0) link_enter_failed(link); return 1; } static int ndisc_request_route(Route *in, Link *link, sd_ndisc_router *rt) { _cleanup_(route_freep) Route *route = in; struct in6_addr router; Route *existing; int r; assert(route); assert(link); assert(rt); r = sd_ndisc_router_get_address(rt, &router); if (r < 0) return r; route->source = NETWORK_CONFIG_SOURCE_NDISC; route->provider.in6 = router; if (!route->table_set) route->table = link_get_ipv6_accept_ra_route_table(link); if (!route->priority_set) route->priority = link->network->ipv6_accept_ra_route_metric; if (!route->protocol_set) route->protocol = RTPROT_RA; if (route_get(NULL, link, route, &existing) < 0) link->ndisc_configured = false; else route_unmark(existing); return link_request_route(link, TAKE_PTR(route), true, &link->ndisc_messages, ndisc_route_handler, NULL); } static int ndisc_address_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) { int r; assert(link); assert(link->ndisc_messages > 0); link->ndisc_messages--; r = address_configure_handler_internal(rtnl, m, link, "Could not set NDisc address"); if (r <= 0) return r; r = ndisc_check_ready(link); if (r < 0) link_enter_failed(link); return 1; } static int ndisc_request_address(Address *in, Link *link, sd_ndisc_router *rt) { _cleanup_(address_freep) Address *address = in; struct in6_addr router; Address *existing; int r; assert(address); assert(link); assert(rt); r = sd_ndisc_router_get_address(rt, &router); if (r < 0) return r; address->source = NETWORK_CONFIG_SOURCE_NDISC; address->provider.in6 = router; if (address_get(link, address, &existing) < 0) link->ndisc_configured = false; else address_unmark(existing); return link_request_address(link, TAKE_PTR(address), true, &link->ndisc_messages, ndisc_address_handler, NULL); } static int ndisc_router_process_default(Link *link, sd_ndisc_router *rt) { usec_t lifetime_usec, timestamp_usec; struct in6_addr gateway; uint16_t lifetime_sec; unsigned preference; uint32_t mtu = 0; int r; assert(link); assert(link->network); assert(rt); if (!link->network->ipv6_accept_ra_use_gateway && hashmap_isempty(link->network->routes_by_section)) return 0; r = sd_ndisc_router_get_lifetime(rt, &lifetime_sec); if (r < 0) return log_link_error_errno(link, r, "Failed to get gateway lifetime from RA: %m"); if (lifetime_sec == 0) /* not a default router */ return 0; r = sd_ndisc_router_get_timestamp(rt, clock_boottime_or_monotonic(), ×tamp_usec); if (r < 0) return log_link_error_errno(link, r, "Failed to get RA timestamp: %m"); lifetime_usec = usec_add(timestamp_usec, lifetime_sec * USEC_PER_SEC); r = sd_ndisc_router_get_address(rt, &gateway); if (r < 0) return log_link_error_errno(link, r, "Failed to get gateway address from RA: %m"); if (link_get_ipv6_address(link, &gateway, NULL) >= 0) { if (DEBUG_LOGGING) { _cleanup_free_ char *buffer = NULL; (void) in6_addr_to_string(&gateway, &buffer); log_link_debug(link, "No NDisc route added, gateway %s matches local address", strna(buffer)); } return 0; } r = sd_ndisc_router_get_preference(rt, &preference); if (r < 0) return log_link_error_errno(link, r, "Failed to get default router preference from RA: %m"); if (link->network->ipv6_accept_ra_use_mtu) { r = sd_ndisc_router_get_mtu(rt, &mtu); if (r < 0 && r != -ENODATA) return log_link_error_errno(link, r, "Failed to get default router MTU from RA: %m"); } if (link->network->ipv6_accept_ra_use_gateway) { _cleanup_(route_freep) Route *route = NULL; r = route_new(&route); if (r < 0) return log_oom(); route->family = AF_INET6; route->pref = preference; route->gw_family = AF_INET6; route->gw.in6 = gateway; route->lifetime_usec = lifetime_usec; route->mtu = mtu; r = ndisc_request_route(TAKE_PTR(route), link, rt); if (r < 0) return log_link_error_errno(link, r, "Could not request default route: %m"); } Route *route_gw; HASHMAP_FOREACH(route_gw, link->network->routes_by_section) { _cleanup_(route_freep) Route *route = NULL; if (!route_gw->gateway_from_dhcp_or_ra) continue; if (route_gw->gw_family != AF_INET6) continue; r = route_dup(route_gw, &route); if (r < 0) return r; route->gw.in6 = gateway; if (!route->pref_set) route->pref = preference; route->lifetime_usec = lifetime_usec; if (route->mtu == 0) route->mtu = mtu; r = ndisc_request_route(TAKE_PTR(route), link, rt); if (r < 0) return log_link_error_errno(link, r, "Could not request gateway: %m"); } return 0; } static int ndisc_router_process_autonomous_prefix(Link *link, sd_ndisc_router *rt) { uint32_t lifetime_valid_sec, lifetime_preferred_sec; usec_t lifetime_valid_usec, lifetime_preferred_usec, timestamp_usec; _cleanup_set_free_ Set *addresses = NULL; struct in6_addr prefix, *a; unsigned prefixlen; int r; assert(link); assert(link->network); assert(rt); if (!link->network->ipv6_accept_ra_use_autonomous_prefix) return 0; r = sd_ndisc_router_get_timestamp(rt, clock_boottime_or_monotonic(), ×tamp_usec); if (r < 0) return log_link_error_errno(link, r, "Failed to get RA timestamp: %m"); r = sd_ndisc_router_prefix_get_address(rt, &prefix); if (r < 0) return log_link_error_errno(link, r, "Failed to get prefix address: %m"); r = sd_ndisc_router_prefix_get_prefixlen(rt, &prefixlen); if (r < 0) return log_link_error_errno(link, r, "Failed to get prefix length: %m"); /* ndisc_generate_addresses() below requires the prefix length <= 64. */ if (prefixlen > 64) { _cleanup_free_ char *buf = NULL; (void) in6_addr_prefix_to_string(&prefix, prefixlen, &buf); log_link_debug(link, "Prefix is longer than 64, ignoring autonomous prefix %s.", strna(buf)); return 0; } r = sd_ndisc_router_prefix_get_valid_lifetime(rt, &lifetime_valid_sec); if (r < 0) return log_link_error_errno(link, r, "Failed to get prefix valid lifetime: %m"); if (lifetime_valid_sec == 0) { log_link_debug(link, "Ignoring prefix as its valid lifetime is zero."); return 0; } r = sd_ndisc_router_prefix_get_preferred_lifetime(rt, &lifetime_preferred_sec); if (r < 0) return log_link_error_errno(link, r, "Failed to get prefix preferred lifetime: %m"); /* The preferred lifetime is never greater than the valid lifetime */ if (lifetime_preferred_sec > lifetime_valid_sec) return 0; lifetime_valid_usec = usec_add(lifetime_valid_sec * USEC_PER_SEC, timestamp_usec); lifetime_preferred_usec = usec_add(lifetime_preferred_sec * USEC_PER_SEC, timestamp_usec); r = ndisc_generate_addresses(link, &prefix, prefixlen, &addresses); if (r < 0) return log_link_error_errno(link, r, "Failed to generate SLAAC addresses: %m"); SET_FOREACH(a, addresses) { _cleanup_(address_freep) Address *address = NULL; Address *e; r = address_new(&address); if (r < 0) return log_oom(); address->family = AF_INET6; address->in_addr.in6 = *a; address->prefixlen = prefixlen; address->flags = IFA_F_NOPREFIXROUTE|IFA_F_MANAGETEMPADDR; address->lifetime_valid_usec = lifetime_valid_usec; address->lifetime_preferred_usec = lifetime_preferred_usec; /* See RFC4862, section 5.5.3.e. But the following logic is deviated from RFC4862 by * honoring all valid lifetimes to improve the reaction of SLAAC to renumbering events. * See draft-ietf-6man-slaac-renum-02, section 4.2. */ r = address_get(link, address, &e); if (r > 0) { /* If the address is already assigned, but not valid anymore, then refuse to * update the address, and it will be removed. */ if (e->lifetime_valid_usec < timestamp_usec) continue; } r = ndisc_request_address(TAKE_PTR(address), link, rt); if (r < 0) return log_link_error_errno(link, r, "Could not request SLAAC address: %m"); } return 0; } static int ndisc_router_process_onlink_prefix(Link *link, sd_ndisc_router *rt) { _cleanup_(route_freep) Route *route = NULL; usec_t timestamp_usec; uint32_t lifetime_sec; unsigned prefixlen; int r; assert(link); assert(link->network); assert(rt); if (!link->network->ipv6_accept_ra_use_onlink_prefix) return 0; r = sd_ndisc_router_prefix_get_valid_lifetime(rt, &lifetime_sec); if (r < 0) return log_link_error_errno(link, r, "Failed to get prefix lifetime: %m"); if (lifetime_sec == 0) return 0; r = sd_ndisc_router_get_timestamp(rt, clock_boottime_or_monotonic(), ×tamp_usec); if (r < 0) return log_link_error_errno(link, r, "Failed to get RA timestamp: %m"); r = sd_ndisc_router_prefix_get_prefixlen(rt, &prefixlen); if (r < 0) return log_link_error_errno(link, r, "Failed to get prefix length: %m"); r = route_new(&route); if (r < 0) return log_oom(); route->family = AF_INET6; route->flags = RTM_F_PREFIX; route->dst_prefixlen = prefixlen; route->lifetime_usec = usec_add(timestamp_usec, lifetime_sec * USEC_PER_SEC); r = sd_ndisc_router_prefix_get_address(rt, &route->dst.in6); if (r < 0) return log_link_error_errno(link, r, "Failed to get prefix address: %m"); r = ndisc_request_route(TAKE_PTR(route), link, rt); if (r < 0) return log_link_error_errno(link, r, "Could not request prefix route: %m");; return 0; } static int ndisc_router_process_prefix(Link *link, sd_ndisc_router *rt) { unsigned prefixlen; struct in6_addr a; uint8_t flags; int r; assert(link); assert(link->network); assert(rt); r = sd_ndisc_router_prefix_get_address(rt, &a); if (r < 0) return log_link_error_errno(link, r, "Failed to get prefix address: %m"); r = sd_ndisc_router_prefix_get_prefixlen(rt, &prefixlen); if (r < 0) return log_link_error_errno(link, r, "Failed to get prefix length: %m"); if (in6_prefix_is_filtered(&a, prefixlen, link->network->ndisc_allow_listed_prefix, link->network->ndisc_deny_listed_prefix)) { if (DEBUG_LOGGING) { _cleanup_free_ char *b = NULL; (void) in6_addr_prefix_to_string(&a, prefixlen, &b); if (!set_isempty(link->network->ndisc_allow_listed_prefix)) log_link_debug(link, "Prefix '%s' is not in allow list, ignoring", strna(b)); else log_link_debug(link, "Prefix '%s' is in deny list, ignoring", strna(b)); } return 0; } r = sd_ndisc_router_prefix_get_flags(rt, &flags); if (r < 0) return log_link_error_errno(link, r, "Failed to get RA prefix flags: %m"); if (FLAGS_SET(flags, ND_OPT_PI_FLAG_ONLINK)) { r = ndisc_router_process_onlink_prefix(link, rt); if (r < 0) return r; } if (FLAGS_SET(flags, ND_OPT_PI_FLAG_AUTO)) { r = ndisc_router_process_autonomous_prefix(link, rt); if (r < 0) return r; } return 0; } static int ndisc_router_process_route(Link *link, sd_ndisc_router *rt) { _cleanup_(route_freep) Route *route = NULL; unsigned preference, prefixlen; struct in6_addr gateway, dst; uint32_t lifetime_sec; usec_t timestamp_usec; int r; assert(link); if (!link->network->ipv6_accept_ra_use_route_prefix) return 0; r = sd_ndisc_router_route_get_lifetime(rt, &lifetime_sec); if (r < 0) return log_link_error_errno(link, r, "Failed to get route lifetime from RA: %m"); if (lifetime_sec == 0) return 0; r = sd_ndisc_router_route_get_address(rt, &dst); if (r < 0) return log_link_error_errno(link, r, "Failed to get route destination address: %m"); r = sd_ndisc_router_route_get_prefixlen(rt, &prefixlen); if (r < 0) return log_link_error_errno(link, r, "Failed to get route prefix length: %m"); if (in6_addr_is_null(&dst) && prefixlen == 0) { log_link_debug(link, "Route prefix is ::/0, ignoring"); return 0; } if (in6_prefix_is_filtered(&dst, prefixlen, link->network->ndisc_allow_listed_route_prefix, link->network->ndisc_deny_listed_route_prefix)) { if (DEBUG_LOGGING) { _cleanup_free_ char *buf = NULL; (void) in6_addr_prefix_to_string(&dst, prefixlen, &buf); if (!set_isempty(link->network->ndisc_allow_listed_route_prefix)) log_link_debug(link, "Route prefix '%s' is not in allow list, ignoring", strna(buf)); else log_link_debug(link, "Route prefix '%s' is in deny list, ignoring", strna(buf)); } return 0; } r = sd_ndisc_router_get_address(rt, &gateway); if (r < 0) return log_link_error_errno(link, r, "Failed to get gateway address from RA: %m"); if (link_get_ipv6_address(link, &gateway, NULL) >= 0) { if (DEBUG_LOGGING) { _cleanup_free_ char *buf = NULL; (void) in6_addr_to_string(&gateway, &buf); log_link_debug(link, "Advertised route gateway %s is local to the link, ignoring route", strna(buf)); } return 0; } r = sd_ndisc_router_route_get_preference(rt, &preference); if (r < 0) return log_link_error_errno(link, r, "Failed to get default router preference from RA: %m"); r = sd_ndisc_router_get_timestamp(rt, clock_boottime_or_monotonic(), ×tamp_usec); if (r < 0) return log_link_error_errno(link, r, "Failed to get RA timestamp: %m"); r = route_new(&route); if (r < 0) return log_oom(); route->family = AF_INET6; route->pref = preference; route->gw.in6 = gateway; route->gw_family = AF_INET6; route->dst.in6 = dst; route->dst_prefixlen = prefixlen; route->lifetime_usec = usec_add(timestamp_usec, lifetime_sec * USEC_PER_SEC); r = ndisc_request_route(TAKE_PTR(route), link, rt); if (r < 0) return log_link_error_errno(link, r, "Could not request additional route: %m"); return 0; } static void ndisc_rdnss_hash_func(const NDiscRDNSS *x, struct siphash *state) { siphash24_compress(&x->address, sizeof(x->address), state); } static int ndisc_rdnss_compare_func(const NDiscRDNSS *a, const NDiscRDNSS *b) { return memcmp(&a->address, &b->address, sizeof(a->address)); } DEFINE_PRIVATE_HASH_OPS_WITH_KEY_DESTRUCTOR( ndisc_rdnss_hash_ops, NDiscRDNSS, ndisc_rdnss_hash_func, ndisc_rdnss_compare_func, free); static int ndisc_router_process_rdnss(Link *link, sd_ndisc_router *rt) { usec_t lifetime_usec, timestamp_usec; uint32_t lifetime_sec; const struct in6_addr *a; struct in6_addr router; bool updated = false; int n, r; assert(link); assert(link->network); assert(rt); if (!link->network->ipv6_accept_ra_use_dns) return 0; r = sd_ndisc_router_get_address(rt, &router); if (r < 0) return log_link_error_errno(link, r, "Failed to get router address from RA: %m"); r = sd_ndisc_router_get_timestamp(rt, clock_boottime_or_monotonic(), ×tamp_usec); if (r < 0) return log_link_error_errno(link, r, "Failed to get RA timestamp: %m"); r = sd_ndisc_router_rdnss_get_lifetime(rt, &lifetime_sec); if (r < 0) return log_link_error_errno(link, r, "Failed to get RDNSS lifetime: %m"); if (lifetime_sec == 0) return 0; lifetime_usec = usec_add(timestamp_usec, lifetime_sec * USEC_PER_SEC); n = sd_ndisc_router_rdnss_get_addresses(rt, &a); if (n < 0) return log_link_error_errno(link, n, "Failed to get RDNSS addresses: %m"); if (n >= (int) NDISC_RDNSS_MAX) { log_link_warning(link, "Too many RDNSS records per link. Only first %i records will be used.", NDISC_RDNSS_MAX); n = NDISC_RDNSS_MAX; } for (int j = 0; j < n; j++) { _cleanup_free_ NDiscRDNSS *x = NULL; NDiscRDNSS *rdnss, d = { .address = a[j], }; rdnss = set_get(link->ndisc_rdnss, &d); if (rdnss) { rdnss->marked = false; rdnss->router = router; rdnss->lifetime_usec = lifetime_usec; continue; } x = new(NDiscRDNSS, 1); if (!x) return log_oom(); *x = (NDiscRDNSS) { .address = a[j], .router = router, .lifetime_usec = lifetime_usec, }; r = set_ensure_consume(&link->ndisc_rdnss, &ndisc_rdnss_hash_ops, TAKE_PTR(x)); if (r < 0) return log_oom(); assert(r > 0); updated = true; } if (updated) link_dirty(link); return 0; } static void ndisc_dnssl_hash_func(const NDiscDNSSL *x, struct siphash *state) { siphash24_compress_string(NDISC_DNSSL_DOMAIN(x), state); } static int ndisc_dnssl_compare_func(const NDiscDNSSL *a, const NDiscDNSSL *b) { return strcmp(NDISC_DNSSL_DOMAIN(a), NDISC_DNSSL_DOMAIN(b)); } DEFINE_PRIVATE_HASH_OPS_WITH_KEY_DESTRUCTOR( ndisc_dnssl_hash_ops, NDiscDNSSL, ndisc_dnssl_hash_func, ndisc_dnssl_compare_func, free); static int ndisc_router_process_dnssl(Link *link, sd_ndisc_router *rt) { _cleanup_strv_free_ char **l = NULL; usec_t lifetime_usec, timestamp_usec; struct in6_addr router; uint32_t lifetime_sec; bool updated = false; char **j; int r; assert(link); assert(link->network); assert(rt); if (link->network->ipv6_accept_ra_use_domains == DHCP_USE_DOMAINS_NO) return 0; r = sd_ndisc_router_get_address(rt, &router); if (r < 0) return log_link_error_errno(link, r, "Failed to get router address from RA: %m"); r = sd_ndisc_router_get_timestamp(rt, clock_boottime_or_monotonic(), ×tamp_usec); if (r < 0) return log_link_error_errno(link, r, "Failed to get RA timestamp: %m"); r = sd_ndisc_router_dnssl_get_lifetime(rt, &lifetime_sec); if (r < 0) return log_link_error_errno(link, r, "Failed to get DNSSL lifetime: %m"); if (lifetime_sec == 0) return 0; lifetime_usec = usec_add(timestamp_usec, lifetime_sec * USEC_PER_SEC); r = sd_ndisc_router_dnssl_get_domains(rt, &l); if (r < 0) return log_link_error_errno(link, r, "Failed to get DNSSL addresses: %m"); if (strv_length(l) >= NDISC_DNSSL_MAX) { log_link_warning(link, "Too many DNSSL records per link. Only first %i records will be used.", NDISC_DNSSL_MAX); STRV_FOREACH(j, l + NDISC_DNSSL_MAX) *j = mfree(*j); } STRV_FOREACH(j, l) { _cleanup_free_ NDiscDNSSL *s = NULL; NDiscDNSSL *dnssl; s = malloc0(ALIGN(sizeof(NDiscDNSSL)) + strlen(*j) + 1); if (!s) return log_oom(); strcpy(NDISC_DNSSL_DOMAIN(s), *j); dnssl = set_get(link->ndisc_dnssl, s); if (dnssl) { dnssl->marked = false; dnssl->router = router; dnssl->lifetime_usec = lifetime_usec; continue; } s->router = router; s->lifetime_usec = lifetime_usec; r = set_ensure_consume(&link->ndisc_dnssl, &ndisc_dnssl_hash_ops, TAKE_PTR(s)); if (r < 0) return log_oom(); assert(r > 0); updated = true; } if (updated) link_dirty(link); return 0; } static int ndisc_router_process_options(Link *link, sd_ndisc_router *rt) { int r; assert(link); assert(link->network); assert(rt); for (r = sd_ndisc_router_option_rewind(rt); ; r = sd_ndisc_router_option_next(rt)) { uint8_t type; if (r < 0) return log_link_error_errno(link, r, "Failed to iterate through options: %m"); if (r == 0) /* EOF */ return 0; r = sd_ndisc_router_option_get_type(rt, &type); if (r < 0) return log_link_error_errno(link, r, "Failed to get RA option type: %m"); switch (type) { case SD_NDISC_OPTION_PREFIX_INFORMATION: r = ndisc_router_process_prefix(link, rt); if (r < 0) return r; break; case SD_NDISC_OPTION_ROUTE_INFORMATION: r = ndisc_router_process_route(link, rt); if (r < 0) return r; break; case SD_NDISC_OPTION_RDNSS: r = ndisc_router_process_rdnss(link, rt); if (r < 0) return r; break; case SD_NDISC_OPTION_DNSSL: r = ndisc_router_process_dnssl(link, rt); if (r < 0) return r; break; } } } static void ndisc_mark(Link *link, const struct in6_addr *router) { NDiscRDNSS *rdnss; NDiscDNSSL *dnssl; assert(link); assert(router); link_mark_addresses(link, NETWORK_CONFIG_SOURCE_NDISC, router); link_mark_routes(link, NETWORK_CONFIG_SOURCE_NDISC, router); SET_FOREACH(rdnss, link->ndisc_rdnss) if (in6_addr_equal(&rdnss->router, router)) rdnss->marked = true; SET_FOREACH(dnssl, link->ndisc_dnssl) if (in6_addr_equal(&dnssl->router, router)) dnssl->marked = true; } static int ndisc_start_dhcp6_client(Link *link, sd_ndisc_router *rt) { int r; assert(link); assert(link->network); switch (link->network->ipv6_accept_ra_start_dhcp6_client) { case IPV6_ACCEPT_RA_START_DHCP6_CLIENT_NO: return 0; case IPV6_ACCEPT_RA_START_DHCP6_CLIENT_YES: { uint64_t flags; r = sd_ndisc_router_get_flags(rt, &flags); if (r < 0) return log_link_warning_errno(link, r, "Failed to get RA flags: %m"); if ((flags & (ND_RA_FLAG_MANAGED | ND_RA_FLAG_OTHER)) == 0) return 0; /* (re)start DHCPv6 client in stateful or stateless mode according to RA flags. * Note, if both managed and other information bits are set, then ignore other * information bit. See RFC 4861. */ r = dhcp6_start_on_ra(link, !(flags & ND_RA_FLAG_MANAGED)); break; } case IPV6_ACCEPT_RA_START_DHCP6_CLIENT_ALWAYS: /* When IPv6AcceptRA.DHCPv6Client=always, start dhcp6 client in managed mode * even if the router flags have neither M nor O flags. */ r = dhcp6_start_on_ra(link, /* information_request = */ false); break; default: assert_not_reached(); } if (r < 0) return log_link_error_errno(link, r, "Could not acquire DHCPv6 lease on NDisc request: %m"); log_link_debug(link, "Acquiring DHCPv6 lease on NDisc request"); return 0; } static int ndisc_router_handler(Link *link, sd_ndisc_router *rt) { struct in6_addr router; int r; assert(link); assert(link->network); assert(link->manager); assert(rt); r = sd_ndisc_router_get_address(rt, &router); if (r < 0) return log_link_error_errno(link, r, "Failed to get router address from RA: %m"); if (in6_prefix_is_filtered(&router, 128, link->network->ndisc_allow_listed_router, link->network->ndisc_deny_listed_router)) { if (DEBUG_LOGGING) { _cleanup_free_ char *buf = NULL; (void) in6_addr_to_string(&router, &buf); if (!set_isempty(link->network->ndisc_allow_listed_router)) log_link_debug(link, "Router '%s' is not in allow list, ignoring", strna(buf)); else log_link_debug(link, "Router '%s' is in deny list, ignoring", strna(buf)); } return 0; } ndisc_mark(link, &router); r = ndisc_start_dhcp6_client(link, rt); if (r < 0) return r; r = ndisc_router_process_default(link, rt); if (r < 0) return r; r = ndisc_router_process_options(link, rt); if (r < 0) return r; if (link->ndisc_messages == 0) { link->ndisc_configured = true; r = ndisc_remove(link, &router); if (r < 0) return r; } else log_link_debug(link, "Setting SLAAC addresses and router."); if (!link->ndisc_configured) link_set_state(link, LINK_STATE_CONFIGURING); link_check_ready(link); return 0; } static void ndisc_handler(sd_ndisc *nd, sd_ndisc_event_t event, sd_ndisc_router *rt, void *userdata) { Link *link = userdata; int r; assert(link); if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER)) return; switch (event) { case SD_NDISC_EVENT_ROUTER: r = ndisc_router_handler(link, rt); if (r < 0) { link_enter_failed(link); return; } break; case SD_NDISC_EVENT_TIMEOUT: log_link_debug(link, "NDisc handler get timeout event"); if (link->ndisc_messages == 0) { link->ndisc_configured = true; link_check_ready(link); } break; default: assert_not_reached(); } } int ndisc_configure(Link *link) { int r; assert(link); if (!link_ipv6_accept_ra_enabled(link)) return 0; if (link->ndisc) return -EBUSY; /* Already configured. */ r = sd_ndisc_new(&link->ndisc); if (r < 0) return r; r = sd_ndisc_attach_event(link->ndisc, link->manager->event, 0); if (r < 0) return r; r = sd_ndisc_set_mac(link->ndisc, &link->hw_addr.ether); if (r < 0) return r; r = sd_ndisc_set_ifindex(link->ndisc, link->ifindex); if (r < 0) return r; r = sd_ndisc_set_callback(link->ndisc, ndisc_handler, link); if (r < 0) return r; return 0; } int ndisc_start(Link *link) { assert(link); if (!link->ndisc || !link->dhcp6_client) return 0; if (!link_has_carrier(link)) return 0; if (in6_addr_is_null(&link->ipv6ll_address)) return 0; log_link_debug(link, "Discovering IPv6 routers"); return sd_ndisc_start(link->ndisc); } void ndisc_vacuum(Link *link) { NDiscRDNSS *r; NDiscDNSSL *d; usec_t time_now; assert(link); /* Removes all RDNSS and DNSSL entries whose validity time has passed */ time_now = now(clock_boottime_or_monotonic()); SET_FOREACH(r, link->ndisc_rdnss) if (r->lifetime_usec < time_now) free(set_remove(link->ndisc_rdnss, r)); SET_FOREACH(d, link->ndisc_dnssl) if (d->lifetime_usec < time_now) free(set_remove(link->ndisc_dnssl, d)); } void ndisc_flush(Link *link) { assert(link); /* Removes all RDNSS and DNSSL entries, without exception */ link->ndisc_rdnss = set_free(link->ndisc_rdnss); link->ndisc_dnssl = set_free(link->ndisc_dnssl); } static const char* const ipv6_accept_ra_start_dhcp6_client_table[_IPV6_ACCEPT_RA_START_DHCP6_CLIENT_MAX] = { [IPV6_ACCEPT_RA_START_DHCP6_CLIENT_NO] = "no", [IPV6_ACCEPT_RA_START_DHCP6_CLIENT_ALWAYS] = "always", [IPV6_ACCEPT_RA_START_DHCP6_CLIENT_YES] = "yes", }; DEFINE_PRIVATE_STRING_TABLE_LOOKUP_FROM_STRING_WITH_BOOLEAN(ipv6_accept_ra_start_dhcp6_client, IPv6AcceptRAStartDHCP6Client, IPV6_ACCEPT_RA_START_DHCP6_CLIENT_YES); DEFINE_CONFIG_PARSE_ENUM(config_parse_ipv6_accept_ra_use_domains, dhcp_use_domains, DHCPUseDomains, "Failed to parse UseDomains= setting"); DEFINE_CONFIG_PARSE_ENUM(config_parse_ipv6_accept_ra_start_dhcp6_client, ipv6_accept_ra_start_dhcp6_client, IPv6AcceptRAStartDHCP6Client, "Failed to parse DHCPv6Client= setting");