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, 6 insertions, 10 deletions

diff --git a/src/network/networkd-dhcp6.c b/src/network/networkd-dhcp6.c
index b9c4b8962c..ccca4e9522 100644
--- a/src/network/networkd-dhcp6.c
+++ b/src/network/networkd-dhcp6.c
@@ -206,6 +206,7 @@ int dhcp6_request_address(Link *link) {
 int dhcp6_configure(Link *link) {
         sd_dhcp6_client *client = NULL;
         int r;
+        const DUID *duid;
 
         assert(link);
 
@@ -234,16 +235,11 @@ int dhcp6_configure(Link *link) {
         if (r < 0)
                 goto error;
 
-        if (link->network->duid_type != _DUID_TYPE_INVALID)
-                r = sd_dhcp6_client_set_duid(client,
-                                             link->network->dhcp_duid_type,
-                                             link->network->dhcp_duid,
-                                             link->network->dhcp_duid_len);
-        else
-                r = sd_dhcp6_client_set_duid(client,
-                                             link->manager->dhcp_duid_type,
-                                             link->manager->dhcp_duid,
-                                             link->manager->dhcp_duid_len);
+        duid = link_duid(link);
+        r = sd_dhcp6_client_set_duid(client,
+                                     duid->type,
+                                     duid->raw_data_len > 0 ? duid->raw_data : NULL,
+                                     duid->raw_data_len);
         if (r < 0)
                 goto error;