]> git.ipfire.org Git - thirdparty/systemd.git/blobdiff - src/resolve/resolved-link.c
Two CODING_STYLE additions
[thirdparty/systemd.git] / src / resolve / resolved-link.c
index 30838ef8cc5bd8870dc22a794e98417006841a84..b0dc65036d9e77e1e32081f66e59bb60b6771b09 100644 (file)
@@ -1,5 +1,3 @@
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
 /***
   This file is part of systemd.
 
@@ -49,6 +47,7 @@ int link_new(Manager *m, Link **ret, int ifindex) {
         l->llmnr_support = RESOLVE_SUPPORT_YES;
         l->mdns_support = RESOLVE_SUPPORT_NO;
         l->dnssec_mode = _DNSSEC_MODE_INVALID;
+        l->operstate = IF_OPER_UNKNOWN;
 
         r = hashmap_put(m->links, INT_TO_PTR(ifindex), l);
         if (r < 0)
@@ -63,15 +62,27 @@ int link_new(Manager *m, Link **ret, int ifindex) {
         return 0;
 }
 
+void link_flush_settings(Link *l) {
+        assert(l);
+
+        l->llmnr_support = RESOLVE_SUPPORT_YES;
+        l->mdns_support = RESOLVE_SUPPORT_NO;
+        l->dnssec_mode = _DNSSEC_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;
 
-        dns_server_unlink_all(l->dns_servers);
-        dns_search_domain_unlink_all(l->search_domains);
+        link_flush_settings(l);
 
         while (l->addresses)
-                link_address_free(l->addresses);
+                (void) link_address_free(l->addresses);
 
         if (l->manager)
                 hashmap_remove(l->manager->links, INT_TO_PTR(l->ifindex));
@@ -82,18 +93,17 @@ Link *link_free(Link *l) {
         dns_scope_free(l->mdns_ipv4_scope);
         dns_scope_free(l->mdns_ipv6_scope);
 
-        set_free_free(l->dnssec_negative_trust_anchors);
-
         free(l);
         return NULL;
 }
 
-static void link_allocate_scopes(Link *l) {
+void link_allocate_scopes(Link *l) {
         int r;
 
         assert(l);
 
-        if (l->dns_servers) {
+        if (link_relevant(l, AF_UNSPEC, false) &&
+            l->dns_servers) {
                 if (!l->unicast_scope) {
                         r = dns_scope_new(l->manager, &l->unicast_scope, l, DNS_PROTOCOL_DNS, AF_UNSPEC);
                         if (r < 0)
@@ -102,7 +112,7 @@ static void link_allocate_scopes(Link *l) {
         } else
                 l->unicast_scope = dns_scope_free(l->unicast_scope);
 
-        if (link_relevant(l, AF_INET) &&
+        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) {
@@ -113,7 +123,7 @@ static void link_allocate_scopes(Link *l) {
         } else
                 l->llmnr_ipv4_scope = dns_scope_free(l->llmnr_ipv4_scope);
 
-        if (link_relevant(l, AF_INET6) &&
+        if (link_relevant(l, AF_INET6, true) &&
             l->llmnr_support != RESOLVE_SUPPORT_NO &&
             l->manager->llmnr_support != RESOLVE_SUPPORT_NO &&
             socket_ipv6_is_supported()) {
@@ -125,7 +135,7 @@ static void link_allocate_scopes(Link *l) {
         } else
                 l->llmnr_ipv6_scope = dns_scope_free(l->llmnr_ipv6_scope);
 
-        if (link_relevant(l, AF_INET) &&
+        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) {
@@ -136,7 +146,7 @@ static void link_allocate_scopes(Link *l) {
         } else
                 l->mdns_ipv4_scope = dns_scope_free(l->mdns_ipv4_scope);
 
-        if (link_relevant(l, AF_INET6) &&
+        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) {
@@ -166,7 +176,8 @@ int link_update_rtnl(Link *l, sd_netlink_message *m) {
         if (r < 0)
                 return r;
 
-        sd_netlink_message_read_u32(m, IFLA_MTU, &l->mtu);
+        (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);
@@ -277,8 +288,29 @@ clear:
         return r;
 }
 
+void link_set_dnssec_mode(Link *l, DnssecMode mode) {
+
+        assert(l);
+
+        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);
@@ -291,12 +323,14 @@ static int link_update_dnssec_mode(Link *l) {
         if (r < 0)
                 goto clear;
 
-        l->dnssec_mode = dnssec_mode_from_string(m);
-        if (l->dnssec_mode < 0) {
+        mode = dnssec_mode_from_string(m);
+        if (mode < 0) {
                 r = -EINVAL;
                 goto clear;
         }
 
+        link_set_dnssec_mode(l, mode);
+
         return 0;
 
 clear:
@@ -341,38 +375,60 @@ clear:
         return r;
 }
 
+static int link_update_search_domain_one(Link *l, const char *name, bool route_only) {
+        DnsSearchDomain *d;
+        int r;
+
+        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 **domains = NULL;
+        _cleanup_strv_free_ char **sdomains = NULL, **rdomains = NULL;
         char **i;
-        int r;
+        int r, q;
 
         assert(l);
 
-        r = sd_network_link_get_domains(l->ifindex, &domains);
-        if (r == -ENODATA) {
+        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;
         }
-        if (r < 0)
-                goto clear;
 
         dns_search_domain_mark_all(l->search_domains);
 
-        STRV_FOREACH(i, domains) {
-                DnsSearchDomain *d;
-
-                r = dns_search_domain_find(l->search_domains, *i, &d);
+        STRV_FOREACH(i, sdomains) {
+                r = link_update_search_domain_one(l, *i, false);
                 if (r < 0)
                         goto clear;
+        }
 
-                if (r > 0)
-                        dns_search_domain_move_back_and_unmark(d);
-                else {
-                        r = dns_search_domain_new(l->manager, NULL, DNS_SEARCH_DOMAIN_LINK, l, *i);
-                        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);
@@ -383,11 +439,45 @@ clear:
         return r;
 }
 
-int link_update_monitor(Link *l) {
+static int link_is_unmanaged(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 1;
+        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_unmanaged(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);
@@ -411,35 +501,55 @@ int link_update_monitor(Link *l) {
         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);
+}
+
+int link_update_monitor(Link *l) {
+        assert(l);
 
+        link_read_settings(l);
         link_allocate_scopes(l);
         link_add_rrs(l, false);
 
         return 0;
 }
 
-bool link_relevant(Link *l, int family) {
+bool link_relevant(Link *l, int family, bool local_multicast) {
         _cleanup_free_ char *state = NULL;
         LinkAddress *a;
 
         assert(l);
 
-        /* A link is relevant if it isn't a loopback or pointopoint
-         * device, has a link beat, can do multicast and has at least
-         * one relevant IP address */
+        /* A link is relevant for local multicast traffic if it isn't a loopback or pointopoint 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_POINTOPOINT|IFF_DORMANT))
+        if (l->flags & (IFF_LOOPBACK|IFF_DORMANT))
                 return false;
 
-        if ((l->flags & (IFF_UP|IFF_LOWER_UP|IFF_MULTICAST)) != (IFF_UP|IFF_LOWER_UP|IFF_MULTICAST))
+        if ((l->flags & (IFF_UP|IFF_LOWER_UP)) != (IFF_UP|IFF_LOWER_UP))
                 return false;
 
-        sd_network_link_get_operational_state(l->ifindex, &state);
+        if (local_multicast) {
+                if (l->flags & IFF_POINTOPOINT)
+                        return false;
+
+                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 (a->family == family && link_address_relevant(a))
+                if ((family == AF_UNSPEC || a->family == family) && link_address_relevant(a, local_multicast))
                         return true;
 
         return false;
@@ -463,12 +573,8 @@ DnsServer* link_set_dns_server(Link *l, DnsServer *s) {
         if (l->current_dns_server == s)
                 return s;
 
-        if (s) {
-                _cleanup_free_ char *ip = NULL;
-
-                in_addr_to_string(s->family, &s->address, &ip);
-                log_info("Switching to DNS server %s for interface %s.", strna(ip), l->name);
-        }
+        if (s)
+                log_info("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);
@@ -504,6 +610,30 @@ void link_next_dns_server(Link *l) {
         link_set_dns_server(l, l->dns_servers);
 }
 
+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;
 
@@ -563,7 +693,7 @@ void link_address_add_rrs(LinkAddress *a, bool force_remove) {
         if (a->family == AF_INET) {
 
                 if (!force_remove &&
-                    link_address_relevant(a) &&
+                    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) {
@@ -620,7 +750,7 @@ void link_address_add_rrs(LinkAddress *a, bool force_remove) {
         if (a->family == AF_INET6) {
 
                 if (!force_remove &&
-                    link_address_relevant(a) &&
+                    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) {
@@ -697,13 +827,13 @@ int link_address_update_rtnl(LinkAddress *a, sd_netlink_message *m) {
         return 0;
 }
 
-bool link_address_relevant(LinkAddress *a) {
+bool link_address_relevant(LinkAddress *a, bool local_multicast) {
         assert(a);
 
         if (a->flags & (IFA_F_DEPRECATED|IFA_F_TENTATIVE))
                 return false;
 
-        if (IN_SET(a->scope, RT_SCOPE_HOST, RT_SCOPE_NOWHERE))
+        if (a->scope >= (local_multicast ? RT_SCOPE_HOST : RT_SCOPE_LINK))
                 return false;
 
         return true;