networkd: clean up vlan handling a bit (#3478)

Let's add a generic parser for VLAN ids, which should become handy as
preparation for PR #3428. Let's also make sure we use uint16_t for the vlan ID
type everywhere, and that validity checks are already applied at the time of
parsing, and not only whne we about to prepare a netdev.

Also, establish a common definition VLANID_INVALID we can use for
non-initialized VLAN id fields.

3 files changed, 11 insertions, 13 deletions

diff --git a/src/network/networkd-netdev-gperf.gperf b/src/network/networkd-netdev-gperf.gperf
index adc64977b9..a9512cd77b 100644
--- a/src/network/networkd-netdev-gperf.gperf
+++ b/src/network/networkd-netdev-gperf.gperf
@@ -3,6 +3,7 @@
 #include "conf-parser.h"
 #include "network-internal.h"
 #include "networkd-netdev-bond.h"
+#include "networkd-netdev-bridge.h"
 #include "networkd-netdev-ipvlan.h"
 #include "networkd-netdev-macvlan.h"
 #include "networkd-netdev-tunnel.h"
@@ -10,8 +11,8 @@
 #include "networkd-netdev-veth.h"
 #include "networkd-netdev-vlan.h"
 #include "networkd-netdev-vxlan.h"
-#include "networkd-netdev-bridge.h"
 #include "networkd-netdev.h"
+#include "vlan-util.h"
 %}
 struct ConfigPerfItem;
 %null_strings
@@ -33,7 +34,7 @@ NetDev.Name,                 config_parse_ifname,                0,
 NetDev.Kind,                 config_parse_netdev_kind,           0,                             offsetof(NetDev, kind)
 NetDev.MTUBytes,             config_parse_iec_size,              0,                             offsetof(NetDev, mtu)
 NetDev.MACAddress,           config_parse_hwaddr,                0,                             offsetof(NetDev, mac)
-VLAN.Id,                     config_parse_uint64,                0,                             offsetof(VLan, id)
+VLAN.Id,                     config_parse_vlanid,                0,                             offsetof(VLan, id)
 MACVLAN.Mode,                config_parse_macvlan_mode,          0,                             offsetof(MacVlan, mode)
 MACVTAP.Mode,                config_parse_macvlan_mode,          0,                             offsetof(MacVlan, mode)
 IPVLAN.Mode,                 config_parse_ipvlan_mode,           0,                             offsetof(IPVlan, mode)
diff --git a/src/network/networkd-netdev-vlan.c b/src/network/networkd-netdev-vlan.c
index b1f4714afa..3cc072388f 100644
--- a/src/network/networkd-netdev-vlan.c
+++ b/src/network/networkd-netdev-vlan.c
@@ -20,6 +20,7 @@
 #include <net/if.h>
 
 #include "networkd-netdev-vlan.h"
+#include "vlan-util.h"
 
 static int netdev_vlan_fill_message_create(NetDev *netdev, Link *link, sd_netlink_message *req) {
         VLan *v;
@@ -33,11 +34,9 @@ static int netdev_vlan_fill_message_create(NetDev *netdev, Link *link, sd_netlin
 
         assert(v);
 
-        if (v->id <= VLANID_MAX) {
-                r = sd_netlink_message_append_u16(req, IFLA_VLAN_ID, v->id);
-                if (r < 0)
-                        return log_netdev_error_errno(netdev, r, "Could not append IFLA_VLAN_ID attribute: %m");
-        }
+        r = sd_netlink_message_append_u16(req, IFLA_VLAN_ID, v->id);
+        if (r < 0)
+                return log_netdev_error_errno(netdev, r, "Could not append IFLA_VLAN_ID attribute: %m");
 
         return 0;
 }
@@ -52,8 +51,8 @@ static int netdev_vlan_verify(NetDev *netdev, const char *filename) {
 
         assert(v);
 
-        if (v->id > VLANID_MAX) {
-                log_warning("VLAN without valid Id (%"PRIu64") configured in %s. Ignoring", v->id, filename);
+        if (v->id == VLANID_INVALID) {
+                log_warning("VLAN without valid Id (%"PRIu16") configured in %s.", v->id, filename);
                 return -EINVAL;
         }
 
@@ -66,7 +65,7 @@ static void vlan_init(NetDev *netdev) {
         assert(netdev);
         assert(v);
 
-        v->id = VLANID_MAX + 1;
+        v->id = VLANID_INVALID;
 }
 
 const NetDevVTable vlan_vtable = {
diff --git a/src/network/networkd-netdev-vlan.h b/src/network/networkd-netdev-vlan.h
index 73aacf4a0f..2dfe314b6e 100644
--- a/src/network/networkd-netdev-vlan.h
+++ b/src/network/networkd-netdev-vlan.h
@@ -23,12 +23,10 @@ typedef struct VLan VLan;
 
 #include "networkd-netdev.h"
 
-#define VLANID_MAX 4094
-
 struct VLan {
         NetDev meta;
 
-        uint64_t id;
+        uint16_t id;
 };
 
 DEFINE_NETDEV_CAST(VLAN, VLan);