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, 9 insertions, 6 deletions

diff --git a/src/network/networkd-network.h b/src/network/networkd-network.h
index 9b8096f9ae..ff2414efdd 100644
--- a/src/network/networkd-network.h
+++ b/src/network/networkd-network.h
@@ -68,6 +68,14 @@ typedef enum LLDPMode {
         _LLDP_MODE_INVALID = -1,
 } LLDPMode;
 
+typedef struct DUID {
+        /* Value of Type in [DHCP] section */
+        DUIDType type;
+
+        uint8_t raw_data_len;
+        uint8_t raw_data[MAX_DUID_LEN];
+} DUID;
+
 typedef struct Manager Manager;
 
 struct Network {
@@ -150,12 +158,7 @@ struct Network {
         struct ether_addr *mac;
         unsigned mtu;
         uint32_t iaid;
-        /* Value of Type in [DUID] section */
-        DUIDType duid_type;
-        /* DUID type code - RFC 3315 */
-        uint16_t dhcp_duid_type;
-        size_t dhcp_duid_len;
-        uint8_t dhcp_duid[MAX_DUID_LEN];
+        DUID duid;
 
         LLDPMode lldp_mode; /* LLDP reception */
         bool lldp_emit;     /* LLDP transmission */