3 files changed, 25 insertions, 28 deletions

diff --git a/src/libsystemd-network/ndisc-router.c b/src/libsystemd-network/ndisc-router.c
index 41ff2b353a..cf56c89d76 100644
--- a/src/libsystemd-network/ndisc-router.c
+++ b/src/libsystemd-network/ndisc-router.c
@@ -91,7 +91,7 @@ _public_ int sd_ndisc_router_get_address(sd_ndisc_router *rt, struct in6_addr *r
         assert_return(rt, -EINVAL);
         assert_return(ret_addr, -EINVAL);
 
-        if (in6_addr_is_null(&rt->address))
+        if (IN6_IS_ADDR_UNSPECIFIED(&rt->address))
                 return -ENODATA;
 
         *ret_addr = rt->address;
diff --git a/src/libsystemd-network/sd-dhcp-client.c b/src/libsystemd-network/sd-dhcp-client.c
index 6475da2c2a..1423264806 100644
--- a/src/libsystemd-network/sd-dhcp-client.c
+++ b/src/libsystemd-network/sd-dhcp-client.c
@@ -386,45 +386,23 @@ int sd_dhcp_client_set_hostname(
                 sd_dhcp_client *client,
                 const char *hostname) {
 
-        char *new_hostname = NULL;
-
         assert_return(client, -EINVAL);
 
-        if (!hostname_is_valid(hostname, false) && !dns_name_is_valid(hostname))
+        /* Refuse hostnames that neither qualify as DNS nor as Linux hosntames */
+        if (hostname &&
+            !(hostname_is_valid(hostname, false) || dns_name_is_valid(hostname) > 0))
                 return -EINVAL;
 
-        if (streq_ptr(client->hostname, hostname))
-                return 0;
-
-        if (hostname) {
-                new_hostname = strdup(hostname);
-                if (!new_hostname)
-                        return -ENOMEM;
-        }
-
-        free(client->hostname);
-        client->hostname = new_hostname;
-
-        return 0;
+        return free_and_strdup(&client->hostname, hostname);
 }
 
 int sd_dhcp_client_set_vendor_class_identifier(
                 sd_dhcp_client *client,
                 const char *vci) {
 
-        char *new_vci = NULL;
-
         assert_return(client, -EINVAL);
 
-        new_vci = strdup(vci);
-        if (!new_vci)
-                return -ENOMEM;
-
-        free(client->vendor_class_identifier);
-
-        client->vendor_class_identifier = new_vci;
-
-        return 0;
+        return free_and_strdup(&client->vendor_class_identifier, vci);
 }
 
 int sd_dhcp_client_set_client_port(
diff --git a/src/libsystemd-network/sd-dhcp-lease.c b/src/libsystemd-network/sd-dhcp-lease.c
index 8387b185c0..7fed55c5fc 100644
--- a/src/libsystemd-network/sd-dhcp-lease.c
+++ b/src/libsystemd-network/sd-dhcp-lease.c
@@ -383,6 +383,23 @@ static int lease_parse_domain(const uint8_t *option, size_t len, char **ret) {
         return 0;
 }
 
+static void filter_bogus_addresses(struct in_addr *addresses, size_t *n) {
+        size_t i, j;
+
+        /* Silently filter DNS/NTP servers supplied to us that do not make outside of the local scope. */
+
+        for (i = 0, j = 0; i < *n; i ++) {
+
+                if (in4_addr_is_null(addresses+i) ||
+                    in4_addr_is_localhost(addresses+i))
+                        continue;
+
+                addresses[j++] = addresses[i];
+        }
+
+        *n = j;
+}
+
 static int lease_parse_in_addrs(const uint8_t *option, size_t len, struct in_addr **ret, size_t *n_ret) {
         assert(option);
         assert(ret);
@@ -404,6 +421,8 @@ static int lease_parse_in_addrs(const uint8_t *option, size_t len, struct in_add
                 if (!addresses)
                         return -ENOMEM;
 
+                filter_bogus_addresses(addresses, &n_addresses);
+
                 free(*ret);
                 *ret = addresses;
                 *n_ret = n_addresses;