sd-network: expose DNS/NTP servers as strings

This avoids having to distinguish between IPv4 and IPv6, allowing us
to keep their internal orderings. The consumers now has to turn the
strings into addresses.

3 files changed, 37 insertions, 88 deletions

diff --git a/src/network/sd-network.c b/src/network/sd-network.c
index 91d6275056..bfb8321c87 100644
--- a/src/network/sd-network.c
+++ b/src/network/sd-network.c
@@ -134,12 +134,13 @@ _public_ int sd_network_get_dhcp_lease(int ifindex, sd_dhcp_lease **ret) {
         return 0;
 }
 
-static int network_get_in_addr(const char *key, int ifindex, struct in_addr **addr) {
+static int network_get_strv(const char *key, int ifindex, char ***ret) {
         _cleanup_free_ char *p = NULL, *s = NULL;
+        _cleanup_strv_free_ char **a = NULL;
         int r;
 
         assert_return(ifindex > 0, -EINVAL);
-        assert_return(addr, -EINVAL);
+        assert_return(ret, -EINVAL);
 
         if (asprintf(&p, "/run/systemd/netif/links/%d", ifindex) < 0)
                 return -ENOMEM;
@@ -147,63 +148,31 @@ static int network_get_in_addr(const char *key, int ifindex, struct in_addr **ad
         r = parse_env_file(p, NEWLINE, key, &s, NULL);
         if (r < 0)
                 return r;
-        else if (!s)
-                return -EIO;
-
-        return deserialize_in_addrs(addr, s);
-}
+        else if (!s) {
+                *ret = NULL;
 
-_public_ int sd_network_get_dns(int ifindex, struct in_addr **addr) {
-        return network_get_in_addr("DNS", ifindex, addr);
-}
-
-static int network_get_in6_addr(const char *key, int ifindex, struct in6_addr **addr) {
-        _cleanup_free_ char *p = NULL, *s = NULL;
-        int r;
-
-        assert_return(ifindex > 0, -EINVAL);
-        assert_return(addr, -EINVAL);
+                return 0;
+        }
 
-        if (asprintf(&p, "/run/systemd/netif/links/%d", ifindex) < 0)
+        a = strv_split(s, " ");
+        if (!a)
                 return -ENOMEM;
 
-        r = parse_env_file(p, NEWLINE, key, &s, NULL);
-        if (r < 0)
-                return r;
-        else if (!s)
-                return -EIO;
-
-        return deserialize_in6_addrs(addr, s);
-}
-
-_public_ int sd_network_get_dns6(int ifindex, struct in6_addr **addr) {
-        return network_get_in6_addr("DNS", ifindex, addr);
-}
+        strv_uniq(a);
+        r = strv_length(a);
 
-static int network_get_boolean(const char *key, int ifindex) {
-        _cleanup_free_ char *p = NULL, *s = NULL;
-        int r;
-
-        assert_return(ifindex > 0, -EINVAL);
-
-        if (asprintf(&p, "/run/systemd/netif/links/%d", ifindex) < 0)
-                return -ENOMEM;
-
-        r = parse_env_file(p, NEWLINE, key, &s, NULL);
-        if (r < 0)
-                return r;
-        else if (!s)
-                return false;
+        *ret = a;
+        a = NULL;
 
-        return parse_boolean(s);
+        return r;
 }
 
-_public_ int sd_network_dhcp_use_dns(int ifindex) {
-        return network_get_boolean("DHCP_USE_DNS", ifindex);
+_public_ int sd_network_get_dns(int ifindex, char ***ret) {
+        return network_get_strv("DNS", ifindex, ret);
 }
 
-_public_ int sd_network_dhcp_use_ntp(int ifindex) {
-        return network_get_boolean("DHCP_USE_NTP", ifindex);
+_public_ int sd_network_get_ntp(int ifindex, char ***ret) {
+        return network_get_strv("NTP", ifindex, ret);
 }
 
 static inline int MONITOR_TO_FD(sd_network_monitor *m) {
diff --git a/src/resolve/resolved-link.c b/src/resolve/resolved-link.c
index 16f41a2604..3c6c757722 100644
--- a/src/resolve/resolved-link.c
+++ b/src/resolve/resolved-link.c
@@ -133,49 +133,33 @@ int link_update_rtnl(Link *l, sd_rtnl_message *m) {
 }
 
 static int link_update_dns_servers(Link *l) {
-        _cleanup_free_ struct in_addr *nameservers = NULL;
-        _cleanup_free_ struct in6_addr *nameservers6 = NULL;
+        _cleanup_strv_free_ char **nameservers = NULL;
+        char **nameserver;
         DnsServer *s, *nx;
-        int r, n, i;
+        int r;
 
         assert(l);
 
         LIST_FOREACH(servers, s, l->dns_servers)
                 s->marked = true;
 
-        n = sd_network_get_dns(l->ifindex, &nameservers);
-        if (n < 0) {
-                r = n;
+        r = sd_network_get_dns(l->ifindex, &nameservers);
+        if (r < 0)
                 goto clear;
-        }
-
-        for (i = 0; i < n; i++) {
-                union in_addr_union a = { .in = nameservers[i] };
-
-                s = link_find_dns_server(l, AF_INET, &a);
-                if (s)
-                        s->marked = false;
-                else {
-                        r = dns_server_new(l->manager, NULL, l, AF_INET, &a);
-                        if (r < 0)
-                                goto clear;
-                }
-        }
 
-        n = sd_network_get_dns6(l->ifindex, &nameservers6);
-        if (n < 0) {
-                r = n;
-                goto clear;
-        }
+        STRV_FOREACH(nameserver, nameservers) {
+                union in_addr_union a;
+                int family;
 
-        for (i = 0; i < n; i++) {
-                union in_addr_union a = { .in6 = nameservers6[i] };
+                r = in_addr_from_string_auto(*nameserver, &family, &a);
+                if (r < 0)
+                        goto clear;
 
-                s = link_find_dns_server(l, AF_INET6, &a);
+                s = link_find_dns_server(l, family, &a);
                 if (s)
                         s->marked = false;
                 else {
-                        r = dns_server_new(l->manager, NULL, l, AF_INET6, &a);
+                        r = dns_server_new(l->manager, NULL, l, family, &a);
                         if (r < 0)
                                 goto clear;
                 }
diff --git a/src/systemd/sd-network.h b/src/systemd/sd-network.h
index e4547057f1..ec01e07e85 100644
--- a/src/systemd/sd-network.h
+++ b/src/systemd/sd-network.h
@@ -76,17 +76,13 @@ int sd_network_get_operational_state(char **state);
 /* Get DHCPv4 lease from ifindex. */
 int sd_network_get_dhcp_lease(int ifindex, sd_dhcp_lease **ret);
 
-/* Returns true if link is configured to respect DNS entries received by DHCP */
-int sd_network_dhcp_use_dns(int ifindex);
+/* Get DNS entries for a given link. These are string representations of
+ * IP addresses */
+int sd_network_get_dns(int ifindex, char ***addr);
 
-/* Returns true if link is configured to respect NTP entries received by DHCP */
-int sd_network_dhcp_use_ntp(int ifindex);
-
-/* Get IPv4 DNS entries statically configured for the link */
-int sd_network_get_dns(int ifindex, struct in_addr **addr);
-
-/* Get IPv6 DNS entries statically configured for the link */
-int sd_network_get_dns6(int ifindex, struct in6_addr **addr);
+/* Get NTP entries for a given link. These are domain names or string
+ * reperesentations of IP addresses */
+int sd_network_get_ntp(int ifindex, char ***addr);
 
 /* Monitor object */
 typedef struct sd_network_monitor sd_network_monitor;