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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 15:35:18 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 15:35:18 +0000
commitb750101eb236130cf056c675997decbac904cc49 (patch)
treea5df1a06754bdd014cb975c051c83b01c9a97532 /src/network/networkd-ndisc.c
parentInitial commit. (diff)
downloadsystemd-b750101eb236130cf056c675997decbac904cc49.tar.xz
systemd-b750101eb236130cf056c675997decbac904cc49.zip
Adding upstream version 252.22.upstream/252.22
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/network/networkd-ndisc.c')
-rw-r--r--src/network/networkd-ndisc.c1211
1 files changed, 1211 insertions, 0 deletions
diff --git a/src/network/networkd-ndisc.c b/src/network/networkd-ndisc.c
new file mode 100644
index 0000000..5fb5d96
--- /dev/null
+++ b/src/network/networkd-ndisc.c
@@ -0,0 +1,1211 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/***
+ Copyright © 2014 Intel Corporation. All rights reserved.
+***/
+
+#include <arpa/inet.h>
+#include <netinet/icmp6.h>
+#include <linux/if.h>
+#include <linux/if_arp.h>
+
+#include "sd-ndisc.h"
+
+#include "event-util.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->iftype == ARPHRD_CAN)
+ return false;
+
+ if (!link->network)
+ return false;
+
+ if (!link_may_have_ipv6ll(link, /* check_multicast = */ true))
+ 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_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;
+
+ 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.");
+
+ link_check_ready(link);
+ return 0;
+}
+
+static int ndisc_route_handler(sd_netlink *rtnl, sd_netlink_message *m, Request *req, Link *link, Route *route) {
+ int r;
+
+ assert(link);
+
+ 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;
+ bool is_new;
+ 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;
+
+ is_new = route_get(NULL, link, route, NULL) < 0;
+
+ r = link_request_route(link, TAKE_PTR(route), true, &link->ndisc_messages,
+ ndisc_route_handler, NULL);
+ if (r < 0)
+ return r;
+ if (r > 0 && is_new)
+ link->ndisc_configured = false;
+
+ return 0;
+}
+
+static int ndisc_address_handler(sd_netlink *rtnl, sd_netlink_message *m, Request *req, Link *link, Address *address) {
+ int r;
+
+ assert(link);
+
+ 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;
+ bool is_new;
+ 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;
+
+ r = free_and_strdup_warn(&address->netlabel, link->network->ndisc_netlabel);
+ if (r < 0)
+ return r;
+
+ is_new = address_get(link, address, NULL) < 0;
+
+ r = link_request_address(link, TAKE_PTR(address), true, &link->ndisc_messages,
+ ndisc_address_handler, NULL);
+ if (r < 0)
+ return r;
+ if (r > 0 && is_new)
+ link->ndisc_configured = false;
+
+ return 0;
+}
+
+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");
+
+ r = sd_ndisc_router_get_timestamp(rt, CLOCK_BOOTTIME, &timestamp_usec);
+ if (r < 0)
+ return log_link_error_errno(link, r, "Failed to get RA timestamp: %m");
+
+ lifetime_usec = sec16_to_usec(lifetime_sec, timestamp_usec);
+
+ 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, 0, NULL) >= 0) {
+ if (DEBUG_LOGGING)
+ log_link_debug(link, "No NDisc route added, gateway %s matches local address",
+ IN6_ADDR_TO_STRING(&gateway));
+ 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, &timestamp_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) {
+ log_link_debug(link, "Prefix is longer than 64, ignoring autonomous prefix %s.",
+ IN6_ADDR_PREFIX_TO_STRING(&prefix, prefixlen));
+ 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");
+
+ 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 = sec_to_usec(lifetime_valid_sec, timestamp_usec);
+ lifetime_preferred_usec = sec_to_usec(lifetime_preferred_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;
+
+ 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;
+
+ 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;
+ struct in6_addr prefix;
+ 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");
+
+ r = sd_ndisc_router_get_timestamp(rt, CLOCK_BOOTTIME, &timestamp_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");
+
+ r = route_new(&route);
+ if (r < 0)
+ return log_oom();
+
+ route->family = AF_INET6;
+ route->flags = RTM_F_PREFIX;
+ route->dst.in6 = prefix;
+ route->dst_prefixlen = prefixlen;
+ route->lifetime_usec = sec_to_usec(lifetime_sec, timestamp_usec);
+
+ 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");
+
+ /* RFC 4861 Section 4.6.2:
+ * A router SHOULD NOT send a prefix option for the link-local prefix and a host SHOULD ignore such
+ * a prefix option. */
+ if (in6_addr_is_link_local(&a)) {
+ log_link_debug(link, "Received link-local prefix, ignoring autonomous prefix.");
+ return 0;
+ }
+
+ 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)
+ log_link_debug(link, "Prefix '%s' is %s, ignoring",
+ !set_isempty(link->network->ndisc_allow_listed_prefix) ? "not in allow list"
+ : "in deny list",
+ IN6_ADDR_PREFIX_TO_STRING(&a, prefixlen));
+ 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");
+
+ 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)
+ log_link_debug(link, "Route prefix %s is %s, ignoring",
+ !set_isempty(link->network->ndisc_allow_listed_route_prefix) ? "not in allow list"
+ : "in deny list",
+ IN6_ADDR_PREFIX_TO_STRING(&dst, prefixlen));
+ 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, 0, NULL) >= 0) {
+ if (DEBUG_LOGGING)
+ log_link_debug(link, "Advertised route gateway %s is local to the link, ignoring route",
+ IN6_ADDR_TO_STRING(&gateway));
+ 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, &timestamp_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 = sec_to_usec(lifetime_sec, timestamp_usec);
+
+ 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, logged_about_too_many = 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, &timestamp_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");
+
+ lifetime_usec = sec_to_usec(lifetime_sec, timestamp_usec);
+
+ 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");
+
+ for (int j = 0; j < n; j++) {
+ _cleanup_free_ NDiscRDNSS *x = NULL;
+ NDiscRDNSS *rdnss, d = {
+ .address = a[j],
+ };
+
+ if (lifetime_usec == 0) {
+ /* The entry is outdated. */
+ free(set_remove(link->ndisc_rdnss, &d));
+ updated = true;
+ continue;
+ }
+
+ rdnss = set_get(link->ndisc_rdnss, &d);
+ if (rdnss) {
+ rdnss->router = router;
+ rdnss->lifetime_usec = lifetime_usec;
+ continue;
+ }
+
+ if (set_size(link->ndisc_rdnss) >= NDISC_RDNSS_MAX) {
+ if (!logged_about_too_many)
+ log_link_warning(link, "Too many RDNSS records per link. Only first %u records will be used.", NDISC_RDNSS_MAX);
+ logged_about_too_many = true;
+ 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, logged_about_too_many = false;
+ 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, &timestamp_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");
+
+ lifetime_usec = sec_to_usec(lifetime_sec, timestamp_usec);
+
+ 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");
+
+ 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);
+
+ if (lifetime_usec == 0) {
+ /* The entry is outdated. */
+ free(set_remove(link->ndisc_dnssl, s));
+ updated = true;
+ continue;
+ }
+
+ dnssl = set_get(link->ndisc_dnssl, s);
+ if (dnssl) {
+ dnssl->router = router;
+ dnssl->lifetime_usec = lifetime_usec;
+ continue;
+ }
+
+ if (set_size(link->ndisc_dnssl) >= NDISC_DNSSL_MAX) {
+ if (!logged_about_too_many)
+ log_link_warning(link, "Too many DNSSL records per link. Only first %u records will be used.", NDISC_DNSSL_MAX);
+ logged_about_too_many = true;
+ 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);
+ break;
+
+ case SD_NDISC_OPTION_ROUTE_INFORMATION:
+ r = ndisc_router_process_route(link, rt);
+ break;
+
+ case SD_NDISC_OPTION_RDNSS:
+ r = ndisc_router_process_rdnss(link, rt);
+ break;
+
+ case SD_NDISC_OPTION_DNSSL:
+ r = ndisc_router_process_dnssl(link, rt);
+ break;
+ }
+ if (r < 0 && r != -EBADMSG)
+ return r;
+ }
+}
+
+static int ndisc_drop_outdated(Link *link, usec_t timestamp_usec) {
+ bool updated = false;
+ NDiscDNSSL *dnssl;
+ NDiscRDNSS *rdnss;
+ Address *address;
+ Route *route;
+ int r = 0, k;
+
+ assert(link);
+
+ /* If an address or friends is already assigned, but not valid anymore, then refuse to update it,
+ * and let's immediately remove it.
+ * 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. */
+
+ SET_FOREACH(route, link->routes) {
+ if (route->source != NETWORK_CONFIG_SOURCE_NDISC)
+ continue;
+
+ if (route->lifetime_usec >= timestamp_usec)
+ continue; /* the route is still valid */
+
+ k = route_remove_and_drop(route);
+ if (k < 0)
+ r = log_link_warning_errno(link, k, "Failed to remove outdated SLAAC route, ignoring: %m");
+ }
+
+ SET_FOREACH(address, link->addresses) {
+ if (address->source != NETWORK_CONFIG_SOURCE_NDISC)
+ continue;
+
+ if (address->lifetime_valid_usec >= timestamp_usec)
+ continue; /* the address is still valid */
+
+ k = address_remove_and_drop(address);
+ if (k < 0)
+ r = log_link_warning_errno(link, k, "Failed to remove outdated SLAAC address, ignoring: %m");
+ }
+
+ SET_FOREACH(rdnss, link->ndisc_rdnss) {
+ if (rdnss->lifetime_usec >= timestamp_usec)
+ continue; /* the DNS server is still valid */
+
+ free(set_remove(link->ndisc_rdnss, rdnss));
+ updated = true;
+ }
+
+ SET_FOREACH(dnssl, link->ndisc_dnssl) {
+ if (dnssl->lifetime_usec >= timestamp_usec)
+ continue; /* the DNS domain is still valid */
+
+ free(set_remove(link->ndisc_dnssl, dnssl));
+ updated = true;
+ }
+
+ if (updated)
+ link_dirty(link);
+
+ return r;
+}
+
+static int ndisc_setup_expire(Link *link);
+
+static int ndisc_expire_handler(sd_event_source *s, uint64_t usec, void *userdata) {
+ Link *link = ASSERT_PTR(userdata);
+ usec_t now_usec;
+
+ assert(link->manager);
+
+ assert_se(sd_event_now(link->manager->event, CLOCK_BOOTTIME, &now_usec) >= 0);
+
+ (void) ndisc_drop_outdated(link, now_usec);
+ (void) ndisc_setup_expire(link);
+ return 0;
+}
+
+static int ndisc_setup_expire(Link *link) {
+ usec_t lifetime_usec = USEC_INFINITY;
+ NDiscDNSSL *dnssl;
+ NDiscRDNSS *rdnss;
+ Address *address;
+ Route *route;
+ int r;
+
+ assert(link);
+ assert(link->manager);
+
+ SET_FOREACH(route, link->routes) {
+ if (route->source != NETWORK_CONFIG_SOURCE_NDISC)
+ continue;
+
+ if (!route_exists(route))
+ continue;
+
+ lifetime_usec = MIN(lifetime_usec, route->lifetime_usec);
+ }
+
+ SET_FOREACH(address, link->addresses) {
+ if (address->source != NETWORK_CONFIG_SOURCE_NDISC)
+ continue;
+
+ if (!address_exists(address))
+ continue;
+
+ lifetime_usec = MIN(lifetime_usec, address->lifetime_valid_usec);
+ }
+
+ SET_FOREACH(rdnss, link->ndisc_rdnss)
+ lifetime_usec = MIN(lifetime_usec, rdnss->lifetime_usec);
+
+ SET_FOREACH(dnssl, link->ndisc_dnssl)
+ lifetime_usec = MIN(lifetime_usec, dnssl->lifetime_usec);
+
+ if (lifetime_usec == USEC_INFINITY)
+ return 0;
+
+ r = event_reset_time(link->manager->event, &link->ndisc_expire, CLOCK_BOOTTIME,
+ lifetime_usec, 0, ndisc_expire_handler, link, 0, "ndisc-expiration", true);
+ if (r < 0)
+ return log_link_warning_errno(link, r, "Failed to update expiration timer for ndisc: %m");
+
+ return 0;
+}
+
+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 configuration" bits are set, then ignore
+ * "other configuration" 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 solicit 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;
+ usec_t timestamp_usec;
+ int r;
+
+ assert(link);
+ assert(link->network);
+ assert(link->manager);
+ assert(rt);
+
+ r = sd_ndisc_router_get_address(rt, &router);
+ if (r == -ENODATA) {
+ log_link_debug(link, "Received RA without router address, ignoring.");
+ return 0;
+ }
+ 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) {
+ if (!set_isempty(link->network->ndisc_allow_listed_router))
+ log_link_debug(link, "Router %s is not in allow list, ignoring.", IN6_ADDR_TO_STRING(&router));
+ else
+ log_link_debug(link, "Router %s is in deny list, ignoring.", IN6_ADDR_TO_STRING(&router));
+ }
+ return 0;
+ }
+
+ r = sd_ndisc_router_get_timestamp(rt, CLOCK_BOOTTIME, &timestamp_usec);
+ if (r == -ENODATA) {
+ log_link_debug(link, "Received RA without timestamp, ignoring.");
+ return 0;
+ }
+ if (r < 0)
+ return r;
+
+ r = ndisc_drop_outdated(link, timestamp_usec);
+ if (r < 0)
+ return r;
+
+ 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;
+
+ r = ndisc_setup_expire(link);
+ if (r < 0)
+ return r;
+
+ if (link->ndisc_messages == 0)
+ link->ndisc_configured = true;
+ 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 = ASSERT_PTR(userdata);
+ int r;
+
+ 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 && r != -EBADMSG) {
+ 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();
+ }
+}
+
+static 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;
+
+ if (link->hw_addr.length == ETH_ALEN) {
+ 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) {
+ int r;
+
+ 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");
+
+ r = sd_ndisc_start(link->ndisc);
+ if (r < 0)
+ return r;
+
+ return 1;
+}
+
+static int ndisc_process_request(Request *req, Link *link, void *userdata) {
+ int r;
+
+ assert(link);
+
+ if (!link_is_ready_to_configure(link, /* allow_unmanaged = */ false))
+ return 0;
+
+ r = ndisc_configure(link);
+ if (r < 0)
+ return log_link_warning_errno(link, r, "Failed to configure IPv6 Router Discovery: %m");
+
+ r = ndisc_start(link);
+ if (r < 0)
+ return log_link_warning_errno(link, r, "Failed to start IPv6 Router Discovery: %m");
+
+ log_link_debug(link, "IPv6 Router Discovery is configured%s.",
+ r > 0 ? " and started" : "");
+ return 1;
+}
+
+int link_request_ndisc(Link *link) {
+ int r;
+
+ assert(link);
+
+ if (!link_ipv6_accept_ra_enabled(link))
+ return 0;
+
+ if (link->ndisc)
+ return 0;
+
+ r = link_queue_request(link, REQUEST_TYPE_NDISC, ndisc_process_request, NULL);
+ if (r < 0)
+ return log_link_warning_errno(link, r, "Failed to request configuring of the IPv6 Router Discovery: %m");
+
+ log_link_debug(link, "Requested configuring of the IPv6 Router Discovery.");
+ return 0;
+}
+
+int ndisc_stop(Link *link) {
+ assert(link);
+
+ link->ndisc_expire = sd_event_source_disable_unref(link->ndisc_expire);
+
+ return sd_ndisc_stop(link->ndisc);
+}
+
+
+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");