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-rw-r--r--src/resolve/resolved-link.c1394
1 files changed, 1394 insertions, 0 deletions
diff --git a/src/resolve/resolved-link.c b/src/resolve/resolved-link.c
new file mode 100644
index 0000000..44f70ac
--- /dev/null
+++ b/src/resolve/resolved-link.c
@@ -0,0 +1,1394 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+
+#include <net/if.h>
+#include <stdio_ext.h>
+
+#include "sd-network.h"
+
+#include "alloc-util.h"
+#include "env-file.h"
+#include "fd-util.h"
+#include "fileio.h"
+#include "missing.h"
+#include "mkdir.h"
+#include "parse-util.h"
+#include "resolved-link.h"
+#include "resolved-llmnr.h"
+#include "resolved-mdns.h"
+#include "string-util.h"
+#include "strv.h"
+#include "tmpfile-util.h"
+
+int link_new(Manager *m, Link **ret, int ifindex) {
+ _cleanup_(link_freep) Link *l = NULL;
+ int r;
+
+ assert(m);
+ assert(ifindex > 0);
+
+ r = hashmap_ensure_allocated(&m->links, NULL);
+ if (r < 0)
+ return r;
+
+ l = new(Link, 1);
+ if (!l)
+ return -ENOMEM;
+
+ *l = (Link) {
+ .ifindex = ifindex,
+ .default_route = -1,
+ .llmnr_support = RESOLVE_SUPPORT_YES,
+ .mdns_support = RESOLVE_SUPPORT_NO,
+ .dnssec_mode = _DNSSEC_MODE_INVALID,
+ .dns_over_tls_mode = _DNS_OVER_TLS_MODE_INVALID,
+ .operstate = IF_OPER_UNKNOWN,
+ };
+
+ if (asprintf(&l->state_file, "/run/systemd/resolve/netif/%i", ifindex) < 0)
+ return -ENOMEM;
+
+ r = hashmap_put(m->links, INT_TO_PTR(ifindex), l);
+ if (r < 0)
+ return r;
+
+ l->manager = m;
+
+ if (ret)
+ *ret = l;
+ l = NULL;
+
+ return 0;
+}
+
+void link_flush_settings(Link *l) {
+ assert(l);
+
+ l->default_route = -1;
+ l->llmnr_support = RESOLVE_SUPPORT_YES;
+ l->mdns_support = RESOLVE_SUPPORT_NO;
+ l->dnssec_mode = _DNSSEC_MODE_INVALID;
+ l->dns_over_tls_mode = _DNS_OVER_TLS_MODE_INVALID;
+
+ dns_server_unlink_all(l->dns_servers);
+ dns_search_domain_unlink_all(l->search_domains);
+
+ l->dnssec_negative_trust_anchors = set_free_free(l->dnssec_negative_trust_anchors);
+}
+
+Link *link_free(Link *l) {
+ if (!l)
+ return NULL;
+
+ /* Send goodbye messages. */
+ dns_scope_announce(l->mdns_ipv4_scope, true);
+ dns_scope_announce(l->mdns_ipv6_scope, true);
+
+ link_flush_settings(l);
+
+ while (l->addresses)
+ (void) link_address_free(l->addresses);
+
+ if (l->manager)
+ hashmap_remove(l->manager->links, INT_TO_PTR(l->ifindex));
+
+ dns_scope_free(l->unicast_scope);
+ dns_scope_free(l->llmnr_ipv4_scope);
+ dns_scope_free(l->llmnr_ipv6_scope);
+ dns_scope_free(l->mdns_ipv4_scope);
+ dns_scope_free(l->mdns_ipv6_scope);
+
+ free(l->state_file);
+
+ return mfree(l);
+}
+
+void link_allocate_scopes(Link *l) {
+ bool unicast_relevant;
+ int r;
+
+ assert(l);
+
+ /* If a link that used to be relevant is no longer, or a link that did not use to be relevant now becomes
+ * relevant, let's reinit the learnt global DNS server information, since we might talk to different servers
+ * now, even if they have the same addresses as before. */
+
+ unicast_relevant = link_relevant(l, AF_UNSPEC, false);
+ if (unicast_relevant != l->unicast_relevant) {
+ l->unicast_relevant = unicast_relevant;
+
+ dns_server_reset_features_all(l->manager->fallback_dns_servers);
+ dns_server_reset_features_all(l->manager->dns_servers);
+
+ /* Also, flush the global unicast scope, to deal with split horizon setups, where talking through one
+ * interface reveals different DNS zones than through others. */
+ if (l->manager->unicast_scope)
+ dns_cache_flush(&l->manager->unicast_scope->cache);
+ }
+
+ /* And now, allocate all scopes that makes sense now if we didn't have them yet, and drop those which we don't
+ * need anymore */
+
+ if (unicast_relevant && l->dns_servers) {
+ if (!l->unicast_scope) {
+ dns_server_reset_features_all(l->dns_servers);
+
+ r = dns_scope_new(l->manager, &l->unicast_scope, l, DNS_PROTOCOL_DNS, AF_UNSPEC);
+ if (r < 0)
+ log_warning_errno(r, "Failed to allocate DNS scope: %m");
+ }
+ } else
+ l->unicast_scope = dns_scope_free(l->unicast_scope);
+
+ if (link_relevant(l, AF_INET, true) &&
+ l->llmnr_support != RESOLVE_SUPPORT_NO &&
+ l->manager->llmnr_support != RESOLVE_SUPPORT_NO) {
+ if (!l->llmnr_ipv4_scope) {
+ r = dns_scope_new(l->manager, &l->llmnr_ipv4_scope, l, DNS_PROTOCOL_LLMNR, AF_INET);
+ if (r < 0)
+ log_warning_errno(r, "Failed to allocate LLMNR IPv4 scope: %m");
+ }
+ } else
+ l->llmnr_ipv4_scope = dns_scope_free(l->llmnr_ipv4_scope);
+
+ if (link_relevant(l, AF_INET6, true) &&
+ l->llmnr_support != RESOLVE_SUPPORT_NO &&
+ l->manager->llmnr_support != RESOLVE_SUPPORT_NO &&
+ socket_ipv6_is_supported()) {
+ if (!l->llmnr_ipv6_scope) {
+ r = dns_scope_new(l->manager, &l->llmnr_ipv6_scope, l, DNS_PROTOCOL_LLMNR, AF_INET6);
+ if (r < 0)
+ log_warning_errno(r, "Failed to allocate LLMNR IPv6 scope: %m");
+ }
+ } else
+ l->llmnr_ipv6_scope = dns_scope_free(l->llmnr_ipv6_scope);
+
+ if (link_relevant(l, AF_INET, true) &&
+ l->mdns_support != RESOLVE_SUPPORT_NO &&
+ l->manager->mdns_support != RESOLVE_SUPPORT_NO) {
+ if (!l->mdns_ipv4_scope) {
+ r = dns_scope_new(l->manager, &l->mdns_ipv4_scope, l, DNS_PROTOCOL_MDNS, AF_INET);
+ if (r < 0)
+ log_warning_errno(r, "Failed to allocate mDNS IPv4 scope: %m");
+ }
+ } else
+ l->mdns_ipv4_scope = dns_scope_free(l->mdns_ipv4_scope);
+
+ if (link_relevant(l, AF_INET6, true) &&
+ l->mdns_support != RESOLVE_SUPPORT_NO &&
+ l->manager->mdns_support != RESOLVE_SUPPORT_NO) {
+ if (!l->mdns_ipv6_scope) {
+ r = dns_scope_new(l->manager, &l->mdns_ipv6_scope, l, DNS_PROTOCOL_MDNS, AF_INET6);
+ if (r < 0)
+ log_warning_errno(r, "Failed to allocate mDNS IPv6 scope: %m");
+ }
+ } else
+ l->mdns_ipv6_scope = dns_scope_free(l->mdns_ipv6_scope);
+}
+
+void link_add_rrs(Link *l, bool force_remove) {
+ LinkAddress *a;
+ int r;
+
+ LIST_FOREACH(addresses, a, l->addresses)
+ link_address_add_rrs(a, force_remove);
+
+ if (!force_remove &&
+ l->mdns_support == RESOLVE_SUPPORT_YES &&
+ l->manager->mdns_support == RESOLVE_SUPPORT_YES) {
+
+ if (l->mdns_ipv4_scope) {
+ r = dns_scope_add_dnssd_services(l->mdns_ipv4_scope);
+ if (r < 0)
+ log_warning_errno(r, "Failed to add IPv4 DNS-SD services: %m");
+ }
+
+ if (l->mdns_ipv6_scope) {
+ r = dns_scope_add_dnssd_services(l->mdns_ipv6_scope);
+ if (r < 0)
+ log_warning_errno(r, "Failed to add IPv6 DNS-SD services: %m");
+ }
+
+ } else {
+
+ if (l->mdns_ipv4_scope) {
+ r = dns_scope_remove_dnssd_services(l->mdns_ipv4_scope);
+ if (r < 0)
+ log_warning_errno(r, "Failed to remove IPv4 DNS-SD services: %m");
+ }
+
+ if (l->mdns_ipv6_scope) {
+ r = dns_scope_remove_dnssd_services(l->mdns_ipv6_scope);
+ if (r < 0)
+ log_warning_errno(r, "Failed to remove IPv6 DNS-SD services: %m");
+ }
+ }
+}
+
+int link_process_rtnl(Link *l, sd_netlink_message *m) {
+ const char *n = NULL;
+ int r;
+
+ assert(l);
+ assert(m);
+
+ r = sd_rtnl_message_link_get_flags(m, &l->flags);
+ if (r < 0)
+ return r;
+
+ (void) sd_netlink_message_read_u32(m, IFLA_MTU, &l->mtu);
+ (void) sd_netlink_message_read_u8(m, IFLA_OPERSTATE, &l->operstate);
+
+ if (sd_netlink_message_read_string(m, IFLA_IFNAME, &n) >= 0) {
+ strncpy(l->name, n, sizeof(l->name)-1);
+ char_array_0(l->name);
+ }
+
+ link_allocate_scopes(l);
+ link_add_rrs(l, false);
+
+ return 0;
+}
+
+static int link_update_dns_server_one(Link *l, const char *name) {
+ union in_addr_union a;
+ DnsServer *s;
+ int family, r;
+
+ assert(l);
+ assert(name);
+
+ r = in_addr_from_string_auto(name, &family, &a);
+ if (r < 0)
+ return r;
+
+ s = dns_server_find(l->dns_servers, family, &a, 0);
+ if (s) {
+ dns_server_move_back_and_unmark(s);
+ return 0;
+ }
+
+ return dns_server_new(l->manager, NULL, DNS_SERVER_LINK, l, family, &a, 0);
+}
+
+static int link_update_dns_servers(Link *l) {
+ _cleanup_strv_free_ char **nameservers = NULL;
+ char **nameserver;
+ int r;
+
+ assert(l);
+
+ r = sd_network_link_get_dns(l->ifindex, &nameservers);
+ if (r == -ENODATA) {
+ r = 0;
+ goto clear;
+ }
+ if (r < 0)
+ goto clear;
+
+ dns_server_mark_all(l->dns_servers);
+
+ STRV_FOREACH(nameserver, nameservers) {
+ r = link_update_dns_server_one(l, *nameserver);
+ if (r < 0)
+ goto clear;
+ }
+
+ dns_server_unlink_marked(l->dns_servers);
+ return 0;
+
+clear:
+ dns_server_unlink_all(l->dns_servers);
+ return r;
+}
+
+static int link_update_default_route(Link *l) {
+ int r;
+
+ assert(l);
+
+ r = sd_network_link_get_dns_default_route(l->ifindex);
+ if (r == -ENODATA) {
+ r = 0;
+ goto clear;
+ }
+ if (r < 0)
+ goto clear;
+
+ l->default_route = r > 0;
+ return 0;
+
+clear:
+ l->default_route = -1;
+ return r;
+}
+
+static int link_update_llmnr_support(Link *l) {
+ _cleanup_free_ char *b = NULL;
+ int r;
+
+ assert(l);
+
+ r = sd_network_link_get_llmnr(l->ifindex, &b);
+ if (r == -ENODATA) {
+ r = 0;
+ goto clear;
+ }
+ if (r < 0)
+ goto clear;
+
+ l->llmnr_support = resolve_support_from_string(b);
+ if (l->llmnr_support < 0) {
+ r = -EINVAL;
+ goto clear;
+ }
+
+ return 0;
+
+clear:
+ l->llmnr_support = RESOLVE_SUPPORT_YES;
+ return r;
+}
+
+static int link_update_mdns_support(Link *l) {
+ _cleanup_free_ char *b = NULL;
+ int r;
+
+ assert(l);
+
+ r = sd_network_link_get_mdns(l->ifindex, &b);
+ if (r == -ENODATA) {
+ r = 0;
+ goto clear;
+ }
+ if (r < 0)
+ goto clear;
+
+ l->mdns_support = resolve_support_from_string(b);
+ if (l->mdns_support < 0) {
+ r = -EINVAL;
+ goto clear;
+ }
+
+ return 0;
+
+clear:
+ l->mdns_support = RESOLVE_SUPPORT_NO;
+ return r;
+}
+
+void link_set_dns_over_tls_mode(Link *l, DnsOverTlsMode mode) {
+
+ assert(l);
+
+#if ! ENABLE_DNS_OVER_TLS
+ if (mode != DNS_OVER_TLS_NO)
+ log_warning("DNS-over-TLS option for the link cannot be set to opportunistic when systemd-resolved is built without DNS-over-TLS support. Turning off DNS-over-TLS support.");
+ return;
+#endif
+
+ l->dns_over_tls_mode = mode;
+}
+
+static int link_update_dns_over_tls_mode(Link *l) {
+ _cleanup_free_ char *b = NULL;
+ int r;
+
+ assert(l);
+
+ r = sd_network_link_get_dns_over_tls(l->ifindex, &b);
+ if (r == -ENODATA) {
+ r = 0;
+ goto clear;
+ }
+ if (r < 0)
+ goto clear;
+
+ l->dns_over_tls_mode = dns_over_tls_mode_from_string(b);
+ if (l->dns_over_tls_mode < 0) {
+ r = -EINVAL;
+ goto clear;
+ }
+
+ return 0;
+
+clear:
+ l->dns_over_tls_mode = _DNS_OVER_TLS_MODE_INVALID;
+ return r;
+}
+
+void link_set_dnssec_mode(Link *l, DnssecMode mode) {
+
+ assert(l);
+
+#if ! HAVE_GCRYPT
+ if (IN_SET(mode, DNSSEC_YES, DNSSEC_ALLOW_DOWNGRADE))
+ log_warning("DNSSEC option for the link cannot be enabled or set to allow-downgrade when systemd-resolved is built without gcrypt support. Turning off DNSSEC support.");
+ return;
+#endif
+
+ if (l->dnssec_mode == mode)
+ return;
+
+ if ((l->dnssec_mode == _DNSSEC_MODE_INVALID) ||
+ (l->dnssec_mode == DNSSEC_NO && mode != DNSSEC_NO) ||
+ (l->dnssec_mode == DNSSEC_ALLOW_DOWNGRADE && mode == DNSSEC_YES)) {
+
+ /* When switching from non-DNSSEC mode to DNSSEC mode, flush the cache. Also when switching from the
+ * allow-downgrade mode to full DNSSEC mode, flush it too. */
+ if (l->unicast_scope)
+ dns_cache_flush(&l->unicast_scope->cache);
+ }
+
+ l->dnssec_mode = mode;
+}
+
+static int link_update_dnssec_mode(Link *l) {
+ _cleanup_free_ char *m = NULL;
+ DnssecMode mode;
+ int r;
+
+ assert(l);
+
+ r = sd_network_link_get_dnssec(l->ifindex, &m);
+ if (r == -ENODATA) {
+ r = 0;
+ goto clear;
+ }
+ if (r < 0)
+ goto clear;
+
+ mode = dnssec_mode_from_string(m);
+ if (mode < 0) {
+ r = -EINVAL;
+ goto clear;
+ }
+
+ link_set_dnssec_mode(l, mode);
+
+ return 0;
+
+clear:
+ l->dnssec_mode = _DNSSEC_MODE_INVALID;
+ return r;
+}
+
+static int link_update_dnssec_negative_trust_anchors(Link *l) {
+ _cleanup_strv_free_ char **ntas = NULL;
+ _cleanup_set_free_free_ Set *ns = NULL;
+ int r;
+
+ assert(l);
+
+ r = sd_network_link_get_dnssec_negative_trust_anchors(l->ifindex, &ntas);
+ if (r == -ENODATA) {
+ r = 0;
+ goto clear;
+ }
+ if (r < 0)
+ goto clear;
+
+ ns = set_new(&dns_name_hash_ops);
+ if (!ns)
+ return -ENOMEM;
+
+ r = set_put_strdupv(ns, ntas);
+ if (r < 0)
+ return r;
+
+ set_free_free(l->dnssec_negative_trust_anchors);
+ l->dnssec_negative_trust_anchors = TAKE_PTR(ns);
+
+ return 0;
+
+clear:
+ l->dnssec_negative_trust_anchors = set_free_free(l->dnssec_negative_trust_anchors);
+ return r;
+}
+
+static int link_update_search_domain_one(Link *l, const char *name, bool route_only) {
+ DnsSearchDomain *d;
+ int r;
+
+ assert(l);
+ assert(name);
+
+ r = dns_search_domain_find(l->search_domains, name, &d);
+ if (r < 0)
+ return r;
+ if (r > 0)
+ dns_search_domain_move_back_and_unmark(d);
+ else {
+ r = dns_search_domain_new(l->manager, &d, DNS_SEARCH_DOMAIN_LINK, l, name);
+ if (r < 0)
+ return r;
+ }
+
+ d->route_only = route_only;
+ return 0;
+}
+
+static int link_update_search_domains(Link *l) {
+ _cleanup_strv_free_ char **sdomains = NULL, **rdomains = NULL;
+ char **i;
+ int r, q;
+
+ assert(l);
+
+ r = sd_network_link_get_search_domains(l->ifindex, &sdomains);
+ if (r < 0 && r != -ENODATA)
+ goto clear;
+
+ q = sd_network_link_get_route_domains(l->ifindex, &rdomains);
+ if (q < 0 && q != -ENODATA) {
+ r = q;
+ goto clear;
+ }
+
+ if (r == -ENODATA && q == -ENODATA) {
+ /* networkd knows nothing about this interface, and that's fine. */
+ r = 0;
+ goto clear;
+ }
+
+ dns_search_domain_mark_all(l->search_domains);
+
+ STRV_FOREACH(i, sdomains) {
+ r = link_update_search_domain_one(l, *i, false);
+ if (r < 0)
+ goto clear;
+ }
+
+ STRV_FOREACH(i, rdomains) {
+ r = link_update_search_domain_one(l, *i, true);
+ if (r < 0)
+ goto clear;
+ }
+
+ dns_search_domain_unlink_marked(l->search_domains);
+ return 0;
+
+clear:
+ dns_search_domain_unlink_all(l->search_domains);
+ return r;
+}
+
+static int link_is_managed(Link *l) {
+ _cleanup_free_ char *state = NULL;
+ int r;
+
+ assert(l);
+
+ r = sd_network_link_get_setup_state(l->ifindex, &state);
+ if (r == -ENODATA)
+ return 0;
+ if (r < 0)
+ return r;
+
+ return !STR_IN_SET(state, "pending", "unmanaged");
+}
+
+static void link_read_settings(Link *l) {
+ int r;
+
+ assert(l);
+
+ /* Read settings from networkd, except when networkd is not managing this interface. */
+
+ r = link_is_managed(l);
+ if (r < 0) {
+ log_warning_errno(r, "Failed to determine whether interface %s is managed: %m", l->name);
+ return;
+ }
+ if (r == 0) {
+
+ /* If this link used to be managed, but is now unmanaged, flush all our settings — but only once. */
+ if (l->is_managed)
+ link_flush_settings(l);
+
+ l->is_managed = false;
+ return;
+ }
+
+ l->is_managed = true;
+
+ r = link_update_dns_servers(l);
+ if (r < 0)
+ log_warning_errno(r, "Failed to read DNS servers for interface %s, ignoring: %m", l->name);
+
+ r = link_update_llmnr_support(l);
+ if (r < 0)
+ log_warning_errno(r, "Failed to read LLMNR support for interface %s, ignoring: %m", l->name);
+
+ r = link_update_mdns_support(l);
+ if (r < 0)
+ log_warning_errno(r, "Failed to read mDNS support for interface %s, ignoring: %m", l->name);
+
+ r = link_update_dns_over_tls_mode(l);
+ if (r < 0)
+ log_warning_errno(r, "Failed to read DNS-over-TLS mode for interface %s, ignoring: %m", l->name);
+
+ r = link_update_dnssec_mode(l);
+ if (r < 0)
+ log_warning_errno(r, "Failed to read DNSSEC mode for interface %s, ignoring: %m", l->name);
+
+ r = link_update_dnssec_negative_trust_anchors(l);
+ if (r < 0)
+ log_warning_errno(r, "Failed to read DNSSEC negative trust anchors for interface %s, ignoring: %m", l->name);
+
+ r = link_update_search_domains(l);
+ if (r < 0)
+ log_warning_errno(r, "Failed to read search domains for interface %s, ignoring: %m", l->name);
+
+ r = link_update_default_route(l);
+ if (r < 0)
+ log_warning_errno(r, "Failed to read default route setting for interface %s, proceeding anyway: %m", l->name);
+}
+
+int link_update(Link *l) {
+ int r;
+
+ assert(l);
+
+ link_read_settings(l);
+ link_load_user(l);
+
+ if (l->llmnr_support != RESOLVE_SUPPORT_NO) {
+ r = manager_llmnr_start(l->manager);
+ if (r < 0)
+ return r;
+ }
+
+ if (l->mdns_support != RESOLVE_SUPPORT_NO) {
+ r = manager_mdns_start(l->manager);
+ if (r < 0)
+ return r;
+ }
+
+ link_allocate_scopes(l);
+ link_add_rrs(l, false);
+
+ return 0;
+}
+
+bool link_relevant(Link *l, int family, bool local_multicast) {
+ _cleanup_free_ char *state = NULL;
+ LinkAddress *a;
+
+ assert(l);
+
+ /* A link is relevant for local multicast traffic if it isn't a loopback device, has a link
+ * beat, can do multicast and has at least one link-local (or better) IP address.
+ *
+ * A link is relevant for non-multicast traffic if it isn't a loopback device, has a link beat, and has at
+ * least one routable address. */
+
+ if (l->flags & (IFF_LOOPBACK|IFF_DORMANT))
+ return false;
+
+ if ((l->flags & (IFF_UP|IFF_LOWER_UP)) != (IFF_UP|IFF_LOWER_UP))
+ return false;
+
+ if (local_multicast) {
+ if ((l->flags & IFF_MULTICAST) != IFF_MULTICAST)
+ return false;
+ }
+
+ /* Check kernel operstate
+ * https://www.kernel.org/doc/Documentation/networking/operstates.txt */
+ if (!IN_SET(l->operstate, IF_OPER_UNKNOWN, IF_OPER_UP))
+ return false;
+
+ (void) sd_network_link_get_operational_state(l->ifindex, &state);
+ if (state && !STR_IN_SET(state, "unknown", "degraded", "routable"))
+ return false;
+
+ LIST_FOREACH(addresses, a, l->addresses)
+ if ((family == AF_UNSPEC || a->family == family) && link_address_relevant(a, local_multicast))
+ return true;
+
+ return false;
+}
+
+LinkAddress *link_find_address(Link *l, int family, const union in_addr_union *in_addr) {
+ LinkAddress *a;
+
+ assert(l);
+
+ LIST_FOREACH(addresses, a, l->addresses)
+ if (a->family == family && in_addr_equal(family, &a->in_addr, in_addr))
+ return a;
+
+ return NULL;
+}
+
+DnsServer* link_set_dns_server(Link *l, DnsServer *s) {
+ assert(l);
+
+ if (l->current_dns_server == s)
+ return s;
+
+ if (s)
+ log_debug("Switching to DNS server %s for interface %s.", dns_server_string(s), l->name);
+
+ dns_server_unref(l->current_dns_server);
+ l->current_dns_server = dns_server_ref(s);
+
+ if (l->unicast_scope)
+ dns_cache_flush(&l->unicast_scope->cache);
+
+ return s;
+}
+
+DnsServer *link_get_dns_server(Link *l) {
+ assert(l);
+
+ if (!l->current_dns_server)
+ link_set_dns_server(l, l->dns_servers);
+
+ return l->current_dns_server;
+}
+
+void link_next_dns_server(Link *l) {
+ assert(l);
+
+ if (!l->current_dns_server)
+ return;
+
+ /* Change to the next one, but make sure to follow the linked
+ * list only if this server is actually still linked. */
+ if (l->current_dns_server->linked && l->current_dns_server->servers_next) {
+ link_set_dns_server(l, l->current_dns_server->servers_next);
+ return;
+ }
+
+ link_set_dns_server(l, l->dns_servers);
+}
+
+DnsOverTlsMode link_get_dns_over_tls_mode(Link *l) {
+ assert(l);
+
+ if (l->dns_over_tls_mode != _DNS_OVER_TLS_MODE_INVALID)
+ return l->dns_over_tls_mode;
+
+ return manager_get_dns_over_tls_mode(l->manager);
+}
+
+DnssecMode link_get_dnssec_mode(Link *l) {
+ assert(l);
+
+ if (l->dnssec_mode != _DNSSEC_MODE_INVALID)
+ return l->dnssec_mode;
+
+ return manager_get_dnssec_mode(l->manager);
+}
+
+bool link_dnssec_supported(Link *l) {
+ DnsServer *server;
+
+ assert(l);
+
+ if (link_get_dnssec_mode(l) == DNSSEC_NO)
+ return false;
+
+ server = link_get_dns_server(l);
+ if (server)
+ return dns_server_dnssec_supported(server);
+
+ return true;
+}
+
+int link_address_new(Link *l, LinkAddress **ret, int family, const union in_addr_union *in_addr) {
+ LinkAddress *a;
+
+ assert(l);
+ assert(in_addr);
+
+ a = new0(LinkAddress, 1);
+ if (!a)
+ return -ENOMEM;
+
+ a->family = family;
+ a->in_addr = *in_addr;
+
+ a->link = l;
+ LIST_PREPEND(addresses, l->addresses, a);
+ l->n_addresses++;
+
+ if (ret)
+ *ret = a;
+
+ return 0;
+}
+
+LinkAddress *link_address_free(LinkAddress *a) {
+ if (!a)
+ return NULL;
+
+ if (a->link) {
+ LIST_REMOVE(addresses, a->link->addresses, a);
+
+ assert(a->link->n_addresses > 0);
+ a->link->n_addresses--;
+
+ if (a->llmnr_address_rr) {
+ if (a->family == AF_INET && a->link->llmnr_ipv4_scope)
+ dns_zone_remove_rr(&a->link->llmnr_ipv4_scope->zone, a->llmnr_address_rr);
+ else if (a->family == AF_INET6 && a->link->llmnr_ipv6_scope)
+ dns_zone_remove_rr(&a->link->llmnr_ipv6_scope->zone, a->llmnr_address_rr);
+ }
+
+ if (a->llmnr_ptr_rr) {
+ if (a->family == AF_INET && a->link->llmnr_ipv4_scope)
+ dns_zone_remove_rr(&a->link->llmnr_ipv4_scope->zone, a->llmnr_ptr_rr);
+ else if (a->family == AF_INET6 && a->link->llmnr_ipv6_scope)
+ dns_zone_remove_rr(&a->link->llmnr_ipv6_scope->zone, a->llmnr_ptr_rr);
+ }
+
+ if (a->mdns_address_rr) {
+ if (a->family == AF_INET && a->link->mdns_ipv4_scope)
+ dns_zone_remove_rr(&a->link->mdns_ipv4_scope->zone, a->mdns_address_rr);
+ else if (a->family == AF_INET6 && a->link->mdns_ipv6_scope)
+ dns_zone_remove_rr(&a->link->mdns_ipv6_scope->zone, a->mdns_address_rr);
+ }
+
+ if (a->mdns_ptr_rr) {
+ if (a->family == AF_INET && a->link->mdns_ipv4_scope)
+ dns_zone_remove_rr(&a->link->mdns_ipv4_scope->zone, a->mdns_ptr_rr);
+ else if (a->family == AF_INET6 && a->link->mdns_ipv6_scope)
+ dns_zone_remove_rr(&a->link->mdns_ipv6_scope->zone, a->mdns_ptr_rr);
+ }
+ }
+
+ dns_resource_record_unref(a->llmnr_address_rr);
+ dns_resource_record_unref(a->llmnr_ptr_rr);
+ dns_resource_record_unref(a->mdns_address_rr);
+ dns_resource_record_unref(a->mdns_ptr_rr);
+
+ return mfree(a);
+}
+
+void link_address_add_rrs(LinkAddress *a, bool force_remove) {
+ int r;
+
+ assert(a);
+
+ if (a->family == AF_INET) {
+
+ if (!force_remove &&
+ link_address_relevant(a, true) &&
+ a->link->llmnr_ipv4_scope &&
+ a->link->llmnr_support == RESOLVE_SUPPORT_YES &&
+ a->link->manager->llmnr_support == RESOLVE_SUPPORT_YES) {
+
+ if (!a->link->manager->llmnr_host_ipv4_key) {
+ a->link->manager->llmnr_host_ipv4_key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, a->link->manager->llmnr_hostname);
+ if (!a->link->manager->llmnr_host_ipv4_key) {
+ r = -ENOMEM;
+ goto fail;
+ }
+ }
+
+ if (!a->llmnr_address_rr) {
+ a->llmnr_address_rr = dns_resource_record_new(a->link->manager->llmnr_host_ipv4_key);
+ if (!a->llmnr_address_rr) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ a->llmnr_address_rr->a.in_addr = a->in_addr.in;
+ a->llmnr_address_rr->ttl = LLMNR_DEFAULT_TTL;
+ }
+
+ if (!a->llmnr_ptr_rr) {
+ r = dns_resource_record_new_reverse(&a->llmnr_ptr_rr, a->family, &a->in_addr, a->link->manager->llmnr_hostname);
+ if (r < 0)
+ goto fail;
+
+ a->llmnr_ptr_rr->ttl = LLMNR_DEFAULT_TTL;
+ }
+
+ r = dns_zone_put(&a->link->llmnr_ipv4_scope->zone, a->link->llmnr_ipv4_scope, a->llmnr_address_rr, true);
+ if (r < 0)
+ log_warning_errno(r, "Failed to add A record to LLMNR zone: %m");
+
+ r = dns_zone_put(&a->link->llmnr_ipv4_scope->zone, a->link->llmnr_ipv4_scope, a->llmnr_ptr_rr, false);
+ if (r < 0)
+ log_warning_errno(r, "Failed to add IPv4 PTR record to LLMNR zone: %m");
+ } else {
+ if (a->llmnr_address_rr) {
+ if (a->link->llmnr_ipv4_scope)
+ dns_zone_remove_rr(&a->link->llmnr_ipv4_scope->zone, a->llmnr_address_rr);
+ a->llmnr_address_rr = dns_resource_record_unref(a->llmnr_address_rr);
+ }
+
+ if (a->llmnr_ptr_rr) {
+ if (a->link->llmnr_ipv4_scope)
+ dns_zone_remove_rr(&a->link->llmnr_ipv4_scope->zone, a->llmnr_ptr_rr);
+ a->llmnr_ptr_rr = dns_resource_record_unref(a->llmnr_ptr_rr);
+ }
+ }
+
+ if (!force_remove &&
+ link_address_relevant(a, true) &&
+ a->link->mdns_ipv4_scope &&
+ a->link->mdns_support == RESOLVE_SUPPORT_YES &&
+ a->link->manager->mdns_support == RESOLVE_SUPPORT_YES) {
+ if (!a->link->manager->mdns_host_ipv4_key) {
+ a->link->manager->mdns_host_ipv4_key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, a->link->manager->mdns_hostname);
+ if (!a->link->manager->mdns_host_ipv4_key) {
+ r = -ENOMEM;
+ goto fail;
+ }
+ }
+
+ if (!a->mdns_address_rr) {
+ a->mdns_address_rr = dns_resource_record_new(a->link->manager->mdns_host_ipv4_key);
+ if (!a->mdns_address_rr) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ a->mdns_address_rr->a.in_addr = a->in_addr.in;
+ a->mdns_address_rr->ttl = MDNS_DEFAULT_TTL;
+ }
+
+ if (!a->mdns_ptr_rr) {
+ r = dns_resource_record_new_reverse(&a->mdns_ptr_rr, a->family, &a->in_addr, a->link->manager->mdns_hostname);
+ if (r < 0)
+ goto fail;
+
+ a->mdns_ptr_rr->ttl = MDNS_DEFAULT_TTL;
+ }
+
+ r = dns_zone_put(&a->link->mdns_ipv4_scope->zone, a->link->mdns_ipv4_scope, a->mdns_address_rr, true);
+ if (r < 0)
+ log_warning_errno(r, "Failed to add A record to MDNS zone: %m");
+
+ r = dns_zone_put(&a->link->mdns_ipv4_scope->zone, a->link->mdns_ipv4_scope, a->mdns_ptr_rr, false);
+ if (r < 0)
+ log_warning_errno(r, "Failed to add IPv4 PTR record to MDNS zone: %m");
+ } else {
+ if (a->mdns_address_rr) {
+ if (a->link->mdns_ipv4_scope)
+ dns_zone_remove_rr(&a->link->mdns_ipv4_scope->zone, a->mdns_address_rr);
+ a->mdns_address_rr = dns_resource_record_unref(a->mdns_address_rr);
+ }
+
+ if (a->mdns_ptr_rr) {
+ if (a->link->mdns_ipv4_scope)
+ dns_zone_remove_rr(&a->link->mdns_ipv4_scope->zone, a->mdns_ptr_rr);
+ a->mdns_ptr_rr = dns_resource_record_unref(a->mdns_ptr_rr);
+ }
+ }
+ }
+
+ if (a->family == AF_INET6) {
+
+ if (!force_remove &&
+ link_address_relevant(a, true) &&
+ a->link->llmnr_ipv6_scope &&
+ a->link->llmnr_support == RESOLVE_SUPPORT_YES &&
+ a->link->manager->llmnr_support == RESOLVE_SUPPORT_YES) {
+
+ if (!a->link->manager->llmnr_host_ipv6_key) {
+ a->link->manager->llmnr_host_ipv6_key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_AAAA, a->link->manager->llmnr_hostname);
+ if (!a->link->manager->llmnr_host_ipv6_key) {
+ r = -ENOMEM;
+ goto fail;
+ }
+ }
+
+ if (!a->llmnr_address_rr) {
+ a->llmnr_address_rr = dns_resource_record_new(a->link->manager->llmnr_host_ipv6_key);
+ if (!a->llmnr_address_rr) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ a->llmnr_address_rr->aaaa.in6_addr = a->in_addr.in6;
+ a->llmnr_address_rr->ttl = LLMNR_DEFAULT_TTL;
+ }
+
+ if (!a->llmnr_ptr_rr) {
+ r = dns_resource_record_new_reverse(&a->llmnr_ptr_rr, a->family, &a->in_addr, a->link->manager->llmnr_hostname);
+ if (r < 0)
+ goto fail;
+
+ a->llmnr_ptr_rr->ttl = LLMNR_DEFAULT_TTL;
+ }
+
+ r = dns_zone_put(&a->link->llmnr_ipv6_scope->zone, a->link->llmnr_ipv6_scope, a->llmnr_address_rr, true);
+ if (r < 0)
+ log_warning_errno(r, "Failed to add AAAA record to LLMNR zone: %m");
+
+ r = dns_zone_put(&a->link->llmnr_ipv6_scope->zone, a->link->llmnr_ipv6_scope, a->llmnr_ptr_rr, false);
+ if (r < 0)
+ log_warning_errno(r, "Failed to add IPv6 PTR record to LLMNR zone: %m");
+ } else {
+ if (a->llmnr_address_rr) {
+ if (a->link->llmnr_ipv6_scope)
+ dns_zone_remove_rr(&a->link->llmnr_ipv6_scope->zone, a->llmnr_address_rr);
+ a->llmnr_address_rr = dns_resource_record_unref(a->llmnr_address_rr);
+ }
+
+ if (a->llmnr_ptr_rr) {
+ if (a->link->llmnr_ipv6_scope)
+ dns_zone_remove_rr(&a->link->llmnr_ipv6_scope->zone, a->llmnr_ptr_rr);
+ a->llmnr_ptr_rr = dns_resource_record_unref(a->llmnr_ptr_rr);
+ }
+ }
+
+ if (!force_remove &&
+ link_address_relevant(a, true) &&
+ a->link->mdns_ipv6_scope &&
+ a->link->mdns_support == RESOLVE_SUPPORT_YES &&
+ a->link->manager->mdns_support == RESOLVE_SUPPORT_YES) {
+
+ if (!a->link->manager->mdns_host_ipv6_key) {
+ a->link->manager->mdns_host_ipv6_key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_AAAA, a->link->manager->mdns_hostname);
+ if (!a->link->manager->mdns_host_ipv6_key) {
+ r = -ENOMEM;
+ goto fail;
+ }
+ }
+
+ if (!a->mdns_address_rr) {
+ a->mdns_address_rr = dns_resource_record_new(a->link->manager->mdns_host_ipv6_key);
+ if (!a->mdns_address_rr) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ a->mdns_address_rr->aaaa.in6_addr = a->in_addr.in6;
+ a->mdns_address_rr->ttl = MDNS_DEFAULT_TTL;
+ }
+
+ if (!a->mdns_ptr_rr) {
+ r = dns_resource_record_new_reverse(&a->mdns_ptr_rr, a->family, &a->in_addr, a->link->manager->mdns_hostname);
+ if (r < 0)
+ goto fail;
+
+ a->mdns_ptr_rr->ttl = MDNS_DEFAULT_TTL;
+ }
+
+ r = dns_zone_put(&a->link->mdns_ipv6_scope->zone, a->link->mdns_ipv6_scope, a->mdns_address_rr, true);
+ if (r < 0)
+ log_warning_errno(r, "Failed to add AAAA record to MDNS zone: %m");
+
+ r = dns_zone_put(&a->link->mdns_ipv6_scope->zone, a->link->mdns_ipv6_scope, a->mdns_ptr_rr, false);
+ if (r < 0)
+ log_warning_errno(r, "Failed to add IPv6 PTR record to MDNS zone: %m");
+ } else {
+ if (a->mdns_address_rr) {
+ if (a->link->mdns_ipv6_scope)
+ dns_zone_remove_rr(&a->link->mdns_ipv6_scope->zone, a->mdns_address_rr);
+ a->mdns_address_rr = dns_resource_record_unref(a->mdns_address_rr);
+ }
+
+ if (a->mdns_ptr_rr) {
+ if (a->link->mdns_ipv6_scope)
+ dns_zone_remove_rr(&a->link->mdns_ipv6_scope->zone, a->mdns_ptr_rr);
+ a->mdns_ptr_rr = dns_resource_record_unref(a->mdns_ptr_rr);
+ }
+ }
+ }
+
+ return;
+
+fail:
+ log_debug_errno(r, "Failed to update address RRs: %m");
+}
+
+int link_address_update_rtnl(LinkAddress *a, sd_netlink_message *m) {
+ int r;
+ assert(a);
+ assert(m);
+
+ r = sd_rtnl_message_addr_get_flags(m, &a->flags);
+ if (r < 0)
+ return r;
+
+ sd_rtnl_message_addr_get_scope(m, &a->scope);
+
+ link_allocate_scopes(a->link);
+ link_add_rrs(a->link, false);
+
+ return 0;
+}
+
+bool link_address_relevant(LinkAddress *a, bool local_multicast) {
+ assert(a);
+
+ if (a->flags & (IFA_F_DEPRECATED|IFA_F_TENTATIVE))
+ return false;
+
+ if (a->scope >= (local_multicast ? RT_SCOPE_HOST : RT_SCOPE_LINK))
+ return false;
+
+ return true;
+}
+
+static bool link_needs_save(Link *l) {
+ assert(l);
+
+ /* Returns true if any of the settings where set different from the default */
+
+ if (l->is_managed)
+ return false;
+
+ if (l->llmnr_support != RESOLVE_SUPPORT_YES ||
+ l->mdns_support != RESOLVE_SUPPORT_NO ||
+ l->dnssec_mode != _DNSSEC_MODE_INVALID ||
+ l->dns_over_tls_mode != _DNS_OVER_TLS_MODE_INVALID)
+ return true;
+
+ if (l->dns_servers ||
+ l->search_domains)
+ return true;
+
+ if (!set_isempty(l->dnssec_negative_trust_anchors))
+ return true;
+
+ if (l->default_route >= 0)
+ return true;
+
+ return false;
+}
+
+int link_save_user(Link *l) {
+ _cleanup_free_ char *temp_path = NULL;
+ _cleanup_fclose_ FILE *f = NULL;
+ const char *v;
+ int r;
+
+ assert(l);
+ assert(l->state_file);
+
+ if (!link_needs_save(l)) {
+ (void) unlink(l->state_file);
+ return 0;
+ }
+
+ r = mkdir_parents(l->state_file, 0700);
+ if (r < 0)
+ goto fail;
+
+ r = fopen_temporary(l->state_file, &f, &temp_path);
+ if (r < 0)
+ goto fail;
+
+ (void) __fsetlocking(f, FSETLOCKING_BYCALLER);
+ (void) fchmod(fileno(f), 0644);
+
+ fputs("# This is private data. Do not parse.\n", f);
+
+ v = resolve_support_to_string(l->llmnr_support);
+ if (v)
+ fprintf(f, "LLMNR=%s\n", v);
+
+ v = resolve_support_to_string(l->mdns_support);
+ if (v)
+ fprintf(f, "MDNS=%s\n", v);
+
+ v = dnssec_mode_to_string(l->dnssec_mode);
+ if (v)
+ fprintf(f, "DNSSEC=%s\n", v);
+
+ if (l->default_route >= 0)
+ fprintf(f, "DEFAULT_ROUTE=%s\n", yes_no(l->default_route));
+
+ if (l->dns_servers) {
+ DnsServer *server;
+
+ fputs("SERVERS=", f);
+ LIST_FOREACH(servers, server, l->dns_servers) {
+
+ if (server != l->dns_servers)
+ fputc(' ', f);
+
+ v = dns_server_string(server);
+ if (!v) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ fputs(v, f);
+ }
+ fputc('\n', f);
+ }
+
+ if (l->search_domains) {
+ DnsSearchDomain *domain;
+
+ fputs("DOMAINS=", f);
+ LIST_FOREACH(domains, domain, l->search_domains) {
+
+ if (domain != l->search_domains)
+ fputc(' ', f);
+
+ if (domain->route_only)
+ fputc('~', f);
+
+ fputs(DNS_SEARCH_DOMAIN_NAME(domain), f);
+ }
+ fputc('\n', f);
+ }
+
+ if (!set_isempty(l->dnssec_negative_trust_anchors)) {
+ bool space = false;
+ Iterator i;
+ char *nta;
+
+ fputs("NTAS=", f);
+ SET_FOREACH(nta, l->dnssec_negative_trust_anchors, i) {
+
+ if (space)
+ fputc(' ', f);
+
+ fputs(nta, f);
+ space = true;
+ }
+ fputc('\n', f);
+ }
+
+ r = fflush_and_check(f);
+ if (r < 0)
+ goto fail;
+
+ if (rename(temp_path, l->state_file) < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ return 0;
+
+fail:
+ (void) unlink(l->state_file);
+
+ if (temp_path)
+ (void) unlink(temp_path);
+
+ return log_error_errno(r, "Failed to save link data %s: %m", l->state_file);
+}
+
+int link_load_user(Link *l) {
+ _cleanup_free_ char
+ *llmnr = NULL,
+ *mdns = NULL,
+ *dnssec = NULL,
+ *servers = NULL,
+ *domains = NULL,
+ *ntas = NULL,
+ *default_route = NULL;
+
+ ResolveSupport s;
+ const char *p;
+ int r;
+
+ assert(l);
+ assert(l->state_file);
+
+ /* Try to load only a single time */
+ if (l->loaded)
+ return 0;
+ l->loaded = true;
+
+ if (l->is_managed)
+ return 0; /* if the device is managed, then networkd is our configuration source, not the bus API */
+
+ r = parse_env_file(NULL, l->state_file,
+ "LLMNR", &llmnr,
+ "MDNS", &mdns,
+ "DNSSEC", &dnssec,
+ "SERVERS", &servers,
+ "DOMAINS", &domains,
+ "NTAS", &ntas,
+ "DEFAULT_ROUTE", &default_route);
+ if (r == -ENOENT)
+ return 0;
+ if (r < 0)
+ goto fail;
+
+ link_flush_settings(l);
+
+ /* If we can't recognize the LLMNR or MDNS setting we don't override the default */
+ s = resolve_support_from_string(llmnr);
+ if (s >= 0)
+ l->llmnr_support = s;
+
+ s = resolve_support_from_string(mdns);
+ if (s >= 0)
+ l->mdns_support = s;
+
+ r = parse_boolean(default_route);
+ if (r >= 0)
+ l->default_route = r;
+
+ /* If we can't recognize the DNSSEC setting, then set it to invalid, so that the daemon default is used. */
+ l->dnssec_mode = dnssec_mode_from_string(dnssec);
+
+ for (p = servers;;) {
+ _cleanup_free_ char *word = NULL;
+
+ r = extract_first_word(&p, &word, NULL, 0);
+ if (r < 0)
+ goto fail;
+ if (r == 0)
+ break;
+
+ r = link_update_dns_server_one(l, word);
+ if (r < 0) {
+ log_debug_errno(r, "Failed to load DNS server '%s', ignoring: %m", word);
+ continue;
+ }
+ }
+
+ for (p = domains;;) {
+ _cleanup_free_ char *word = NULL;
+ const char *n;
+ bool is_route;
+
+ r = extract_first_word(&p, &word, NULL, 0);
+ if (r < 0)
+ goto fail;
+ if (r == 0)
+ break;
+
+ is_route = word[0] == '~';
+ n = is_route ? word + 1 : word;
+
+ r = link_update_search_domain_one(l, n, is_route);
+ if (r < 0) {
+ log_debug_errno(r, "Failed to load search domain '%s', ignoring: %m", word);
+ continue;
+ }
+ }
+
+ if (ntas) {
+ _cleanup_set_free_free_ Set *ns = NULL;
+
+ ns = set_new(&dns_name_hash_ops);
+ if (!ns) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ r = set_put_strsplit(ns, ntas, NULL, 0);
+ if (r < 0)
+ goto fail;
+
+ l->dnssec_negative_trust_anchors = TAKE_PTR(ns);
+ }
+
+ return 0;
+
+fail:
+ return log_error_errno(r, "Failed to load link data %s: %m", l->state_file);
+}
+
+void link_remove_user(Link *l) {
+ assert(l);
+ assert(l->state_file);
+
+ (void) unlink(l->state_file);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-26 10:05:24 +0000