networkd: Honor configured DHCP ClientIdentifier on link_update (#6622)

We have an embedded board with a couple of ethernet ports. From the kernel
log, I can see that the ethernet drivers are obtaining their correct MAC
address, but for some reason, at first systemd-networkd doesn't see the
mac address for the ethernet port at the time that it looks at
dhcp_client_identifier configuration (it has 00:00:00:00:00:00 for mac).

Later on, systemd-networkd gets a link_update() call, and at this time, it
has the correct mac address for the ethernet port. However, in link_update()
the dhcp_client_identifier configuration is not being considered, and a call
to sd_dhcp_client_set_iaid_duid() is being done always

diff --git a/src/network/networkd-link.c b/src/network/networkd-link.c
index 03b8f8c3c4047c56ca46c8adaec7ce1f9ce923cf..cba08738713f60cbd33c278ef2970d3c9d4c4f40 100644 (file)
--- a/src/network/networkd-link.c
+++ b/src/network/networkd-link.c
@@ -3186,8 +3186,6 @@ int link_update(Link *link, sd_netlink_message *m) {
                         }
 
                         if (link->dhcp_client) {
-                                const DUID *duid = link_duid(link);
-
                                 r = sd_dhcp_client_set_mac(link->dhcp_client,
                                                            (const uint8_t *) &link->mac,
                                                            sizeof (link->mac),
@@ -3195,13 +3193,30 @@ int link_update(Link *link, sd_netlink_message *m) {
                                 if (r < 0)
                                         return log_link_warning_errno(link, r, "Could not update MAC address in DHCP client: %m");
 
-                                r = sd_dhcp_client_set_iaid_duid(link->dhcp_client,
-                                                                 link->network->iaid,
-                                                                 duid->type,
-                                                                 duid->raw_data_len > 0 ? duid->raw_data : NULL,
-                                                                 duid->raw_data_len);
-                                if (r < 0)
-                                        return log_link_warning_errno(link, r, "Could not update DUID/IAID in DHCP client: %m");
+                                switch (link->network->dhcp_client_identifier) {
+                                case DHCP_CLIENT_ID_DUID: {
+                                        const DUID *duid = link_duid(link);
+
+                                        r = sd_dhcp_client_set_iaid_duid(link->dhcp_client,
+                                                                         link->network->iaid,
+                                                                         duid->type,
+                                                                         duid->raw_data_len > 0 ? duid->raw_data : NULL,
+                                                                         duid->raw_data_len);
+                                        if (r < 0)
+                                                return log_link_warning_errno(link, r, "Could not update DUID/IAID in DHCP client: %m");
+                                        break;
+                                }
+                                case DHCP_CLIENT_ID_MAC:
+                                        r = sd_dhcp_client_set_client_id(link->dhcp_client,
+                                                                         ARPHRD_ETHER,
+                                                                         (const uint8_t *)&link->mac,
+                                                                         sizeof(link->mac));
+                                        if(r < 0)
+                                                return log_link_warning_errno(link, r, "Could not update MAC client id in DHCP client: %m");
+                                        break;
+                                default:
+                                        assert_not_reached("Unknown client identifier type.");
+                                }
                         }
 
                         if (link->dhcp6_client) {