networkd: update mac address in clients when it changes

Pass the mac address on to ipv4ll and dhcp clients so they always have
up-to-date information, and may react appropriately to the change.

Also drop setting the mac address from uevent, and only log when the
address actually changes.

2 files changed, 37 insertions, 22 deletions

diff --git a/src/network/networkd-link.c b/src/network/networkd-link.c
index 275ad97a63..e60ba9d61b 100644
--- a/src/network/networkd-link.c
+++ b/src/network/networkd-link.c
@@ -32,8 +32,6 @@
 
 int link_new(Manager *manager, struct udev_device *device, Link **ret) {
         _cleanup_link_free_ Link *link = NULL;
-        const char *mac;
-        struct ether_addr *mac_addr;
         const char *ifname;
         int r;
 
@@ -58,13 +56,6 @@ int link_new(Manager *manager, struct udev_device *device, Link **ret) {
         if (r < 0)
                 return -ENOMEM;
 
-        mac = udev_device_get_sysattr_value(device, "address");
-        if (mac) {
-                mac_addr = ether_aton(mac);
-                if (mac_addr)
-                        memcpy(&link->mac, mac_addr, sizeof(struct ether_addr));
-        }
-
         ifname = udev_device_get_sysname(device);
         link->ifname = strdup(ifname);
 
@@ -972,6 +963,9 @@ static int link_update_flags(Link *link, unsigned flags) {
         if (link->flags == flags)
                 return 0;
 
+        log_debug_link(link, "link status updated: %#.8x -> %#.8x",
+                       link->flags, flags);
+
         if ((link->flags & IFF_UP) != (flags & IFF_UP))
                 log_info_link(link,
                               "link is %s", flags & IFF_UP ? "up": "down");
@@ -1011,9 +1005,6 @@ static int link_update_flags(Link *link, unsigned flags) {
                 }
         }
 
-        log_debug_link(link, "link status updated: %#.8x -> %#.8x",
-                       link->flags, flags);
-
         link->flags = flags;
 
         return 0;
@@ -1321,6 +1312,7 @@ int link_add(Manager *m, struct udev_device *device, Link **ret) {
 
 int link_update(Link *link, sd_rtnl_message *m) {
         unsigned flags;
+        struct ether_addr mac;
         int r;
 
         assert(link);
@@ -1338,16 +1330,39 @@ int link_update(Link *link, sd_rtnl_message *m) {
                                        PRIu16, link->original_mtu);
         }
 
-        r = sd_rtnl_message_read_ether_addr(m, IFLA_ADDRESS, &link->mac);
-        if (r >= 0) {
+        r = sd_rtnl_message_read_ether_addr(m, IFLA_ADDRESS, &mac);
+        if (r >= 0 && memcmp(&link->mac.ether_addr_octet, &mac.ether_addr_octet, ETH_ALEN)) {
+
+                memcpy(&link->mac.ether_addr_octet, &mac.ether_addr_octet, ETH_ALEN);
+
                 log_debug_link(link, "MAC address: "
                                "%02hhx:%02hhx:%02hhx:%02hhx:%02hhx:%02hhx",
-                                link->mac.ether_addr_octet[0],
-                                link->mac.ether_addr_octet[1],
-                                link->mac.ether_addr_octet[2],
-                                link->mac.ether_addr_octet[3],
-                                link->mac.ether_addr_octet[4],
-                                link->mac.ether_addr_octet[5]);
+                                mac.ether_addr_octet[0],
+                                mac.ether_addr_octet[1],
+                                mac.ether_addr_octet[2],
+                                mac.ether_addr_octet[3],
+                                mac.ether_addr_octet[4],
+                                mac.ether_addr_octet[5]);
+
+                if (link->ipv4ll) {
+                        r = sd_ipv4ll_set_mac(link->ipv4ll, &link->mac);
+                        if (r < 0) {
+                                log_warning_link(link, "Could not update MAC "
+                                                 "address in IPv4LL client: %s",
+                                                 strerror(-r));
+                                return r;
+                        }
+                }
+
+                if (link->dhcp_client) {
+                        r = sd_dhcp_client_set_mac(link->dhcp_client, &link->mac);
+                        if (r < 0) {
+                                log_warning_link(link, "Could not update MAC "
+                                                 "address in DHCP client: %s",
+                                                 strerror(-r));
+                                return r;
+                        }
+                }
         }
 
         r = sd_rtnl_message_link_get_flags(m, &flags);
diff --git a/src/network/networkd-manager.c b/src/network/networkd-manager.c
index ea414b1f1e..46815e0fd0 100644
--- a/src/network/networkd-manager.c
+++ b/src/network/networkd-manager.c
@@ -312,13 +312,13 @@ static int manager_rtnl_process_link(sd_rtnl *rtnl, sd_rtnl_message *message, vo
 
         r = sd_rtnl_message_link_get_ifindex(message, &ifindex);
         if (r < 0 || ifindex <= 0) {
-                log_debug("received RTM_NEWLINK message without valid ifindex");
+                log_warning("received RTM_NEWLINK message without valid ifindex");
                 return 0;
         }
 
         r = sd_rtnl_message_read_string(message, IFLA_IFNAME, &name);
         if (r < 0)
-                log_debug("received RTM_NEWLINK message without valid IFLA_IFNAME");
+                log_warning("received RTM_NEWLINK message without valid ifname");
         else {
                 NetDev *netdev;