networkd: rework duid_{type,duid_type,duid,duid_len} setting

Separate fields are replaced  with a struct.

Second second duid type field is removed. The first field was used to carry
the result of DUIDType= configuration, and the second was either a copy of
this, or contained the type extracted from DuidRawData. The semantics are changed
so that the type specified in DUIDType is always used. DUIDRawData= no longer
overrides the type setting.

The networkd code is now more constrained than the sd-dhcp code:
DUIDRawData cannot have 0 length, length 0 is treated the same as unsetting.
Likewise, it is not possible to set a DUIDType=0. If it ever becomes necessary
to set type=0 or a zero-length duid, the code can be changed to support that.
Nevertheless, I think that's unlikely.

This addresses #3127 § 1 and 3.

v2:
- rename DUID.duid, DUID.duid_len to DUID.raw_data, DUID.raw_data_len

1 files changed, 10 insertions, 14 deletions

diff --git a/src/network/networkd-dhcp4.c b/src/network/networkd-dhcp4.c
index d31ea4d066..89926e8a7e 100644
--- a/src/network/networkd-dhcp4.c
+++ b/src/network/networkd-dhcp4.c
@@ -628,28 +628,24 @@ int dhcp4_configure(Link *link) {
         }
 
         switch (link->network->dhcp_client_identifier) {
-        case DHCP_CLIENT_ID_DUID:
+        case DHCP_CLIENT_ID_DUID: {
                 /* If configured, apply user specified DUID and/or IAID */
-                if (link->network->duid_type != _DUID_TYPE_INVALID)
-                        r = sd_dhcp_client_set_iaid_duid(link->dhcp_client,
-                                                         link->network->iaid,
-                                                         link->network->dhcp_duid_type,
-                                                         link->network->dhcp_duid,
-                                                         link->network->dhcp_duid_len);
-                else
-                        r = sd_dhcp_client_set_iaid_duid(link->dhcp_client,
-                                                         link->network->iaid,
-                                                         link->manager->dhcp_duid_type,
-                                                         link->manager->dhcp_duid,
-                                                         link->manager->dhcp_duid_len);
+                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 r;
                 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));
+                                                 sizeof(link->mac));
                 if (r < 0)
                         return r;
                 break;