bridge-vlan: add support for defining aliases for vlan ids

When defining a bridge-vlan like this:

config bridge-vlan
	option device 'switch0'
	option vlan '1'
	option ports 'lan1 lan2 lan3 lan4'
	option alias 'lan'

You can use switch0.lan instead of switch0.1 to refer to the VLAN.
This ensures that the VLAN ID can be kept in a single place in the config

Signed-off-by: Felix Fietkau <nbd@nbd.name>

bridge.c

@@ -761,6 +761,7 @@ bridge_free(struct device *dev)
 	bst = container_of(dev, struct bridge_state, dev);
 	vlist_flush_all(&bst->members);
 	vlist_flush_all(&dev->vlans);
+	kvlist_free(&dev->vlan_aliases);
 	free(bst->config_data);
 	free(bst);
 }

config.c

@@ -279,15 +279,18 @@ config_parse_vlan(struct device *dev, struct uci_section *s)
 		BRVLAN_ATTR_VID,
 		BRVLAN_ATTR_LOCAL,
 		BRVLAN_ATTR_PORTS,
+		BRVLAN_ATTR_ALIAS,
 		__BRVLAN_ATTR_MAX,
 	};
 	static const struct blobmsg_policy vlan_attrs[__BRVLAN_ATTR_MAX] = {
 		[BRVLAN_ATTR_VID] = { "vlan", BLOBMSG_TYPE_INT32 },
 		[BRVLAN_ATTR_LOCAL] = { "local", BLOBMSG_TYPE_BOOL },
 		[BRVLAN_ATTR_PORTS] = { "ports", BLOBMSG_TYPE_ARRAY },
+		[BRVLAN_ATTR_ALIAS] = { "alias", BLOBMSG_TYPE_ARRAY },
 	};
 	static const struct uci_blob_param_info vlan_attr_info[__BRVLAN_ATTR_MAX] = {
 		[BRVLAN_ATTR_PORTS] = { .type = BLOBMSG_TYPE_STRING },
+		[BRVLAN_ATTR_ALIAS] = { .type = BLOBMSG_TYPE_STRING },
 	};
 	static const struct uci_blob_param_list vlan_attr_list = {
 		.n_params = __BRVLAN_ATTR_MAX,
@@ -363,6 +366,9 @@ config_parse_vlan(struct device *dev, struct uci_section *s)
 		port++;
 	}
 
+	blobmsg_for_each_attr(cur, tb[BRVLAN_ATTR_ALIAS], rem)
+		kvlist_set(&dev->vlan_aliases, blobmsg_get_string(cur), &vid);
+
 	vlist_add(&dev->vlans, &vlan->node, &vlan->vid);
 }
 

device.c

@@ -109,6 +109,11 @@ void device_unlock(void)
 		device_free_unused(NULL);
 }
 
+static int device_vlan_len(struct kvlist *kv, const void *data)
+{
+	return sizeof(unsigned int);
+}
+
 void device_vlan_update(bool done)
 {
 	struct device *dev;
@@ -117,10 +122,15 @@ void device_vlan_update(bool done)
 		if (!dev->vlans.update)
 			continue;
 
-		if (!done)
+		if (!done) {
+			if (dev->vlan_aliases.get_len)
+				kvlist_free(&dev->vlan_aliases);
+			else
+				kvlist_init(&dev->vlan_aliases, device_vlan_len);
 			vlist_update(&dev->vlans);
-		else
+		} else {
 			vlist_flush(&dev->vlans);
+		}
 	}
 }
 

device.h

@@ -16,6 +16,7 @@
 
 #include <libubox/avl.h>
 #include <libubox/safe_list.h>
+#include <libubox/kvlist.h>
 #include <netinet/in.h>
 
 struct device;
@@ -186,6 +187,7 @@ struct device {
 	struct safe_list aliases;
 
 	struct vlist_tree vlans;
+	struct kvlist vlan_aliases;
 
 	char ifname[IFNAMSIZ + 1];
 	int ifindex;

vlan.c

@@ -161,7 +161,7 @@ vlan_config_init(struct device *dev)
 	vlan_hotplug_check(vldev, vldev->dep.dev);
 }
 
-static struct device *get_vlan_device(struct device *dev, int id, bool create)
+static struct device *get_vlan_device(struct device *dev, char *id_str, bool create)
 {
 	static struct device_type vlan_type = {
 		.name = "VLAN",
@@ -172,6 +172,17 @@ static struct device *get_vlan_device(struct device *dev, int id, bool create)
 	struct vlan_device *vldev;
 	struct device_user *dep;
 	char name[IFNAMSIZ + 1];
+	char *err = NULL;
+	int id, *alias_id;
+
+	id = strtoul(id_str, &err, 10);
+	if (err && *err) {
+		alias_id = kvlist_get(&dev->vlan_aliases, id_str);
+		if (!alias_id)
+			return NULL;
+
+		id = *alias_id;
+	}
 
 	/* look for an existing interface before creating a new one */
 	list_for_each_entry(dep, &dev->users.list, list.list) {
@@ -238,8 +249,7 @@ out:
 struct device *get_vlan_device_chain(const char *ifname, bool create)
 {
 	struct device *dev = NULL;
-	char *buf, *s, *next, *err = NULL;
-	int id;
+	char *buf, *s, *next;
 
 	buf = strdup(ifname);
 	if (!buf)
@@ -252,11 +262,7 @@ struct device *get_vlan_device_chain(const char *ifname, bool create)
 
 	do {
 		next = split_vlan(s);
-		id = strtoul(s, &err, 10);
-		if (err && *err)
-			goto error;
-
-		dev = get_vlan_device(dev, id, create);
+		dev = get_vlan_device(dev, s, create);
 		if (!dev)
 			goto error;