resolved: rework what ResolveHostname() with family == AF_UNSPEC means

[thirdparty/systemd.git] / src / resolve / resolved-link.c

diff --git a/src/resolve/resolved-link.c b/src/resolve/resolved-link.c
index b203f19dbbdf7dbbb0f8c120e637fd88f2698cfc..7412e6462296bdc1a781654f913e35d504d557f9 100644 (file)
--- a/src/resolve/resolved-link.c
+++ b/src/resolve/resolved-link.c
@@ -49,6 +49,7 @@ 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)
@@ -177,7 +178,8 @@ 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);
@@ -375,38 +377,60 @@ 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);
@@ -491,14 +515,17 @@ int link_update_monitor(Link *l) {
         return 0;
 }
 
-bool link_relevant(Link *l, int family, bool multicast) {
+bool link_relevant(Link *l, int family, bool local_multicast) {
         _cleanup_free_ char *state = NULL;
         LinkAddress *a;
 
         assert(l);
 
-        /* A link is relevant for multicast traffic 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_DORMANT))
                 return false;
@@ -506,7 +533,7 @@ bool link_relevant(Link *l, int family, bool multicast) {
         if ((l->flags & (IFF_UP|IFF_LOWER_UP)) != (IFF_UP|IFF_LOWER_UP))
                 return false;
 
-        if (multicast) {
+        if (local_multicast) {
                 if (l->flags & IFF_POINTOPOINT)
                         return false;
 
@@ -514,12 +541,17 @@ bool link_relevant(Link *l, int family, bool multicast) {
                         return false;
         }
 
-        sd_network_link_get_operational_state(l->ifindex, &state);
+        /* 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))
+                if ((family == AF_UNSPEC || a->family == family) && link_address_relevant(a, local_multicast))
                         return true;
 
         return false;
@@ -663,7 +695,7 @@ 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) {
@@ -720,7 +752,7 @@ 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) {
@@ -797,13 +829,13 @@ 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;