From: Felix Fietkau Date: Wed, 24 Mar 2021 02:30:35 +0100 Subject: [PATCH] net: bridge: resolve forwarding path for VLAN tag actions in bridge devices Depending on the VLAN settings of the bridge and the port, the bridge can either add or remove a tag. When vlan filtering is enabled, the fdb lookup also needs to know the VLAN tag/proto for the destination address To provide this, keep track of the stack of VLAN tags for the path in the lookup context Signed-off-by: Felix Fietkau Signed-off-by: Pablo Neira Ayuso --- --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -841,10 +841,20 @@ struct net_device_path { u16 id; __be16 proto; } encap; + struct { + enum { + DEV_PATH_BR_VLAN_KEEP, + DEV_PATH_BR_VLAN_TAG, + DEV_PATH_BR_VLAN_UNTAG, + } vlan_mode; + u16 vlan_id; + __be16 vlan_proto; + } bridge; }; }; #define NET_DEVICE_PATH_STACK_MAX 5 +#define NET_DEVICE_PATH_VLAN_MAX 2 struct net_device_path_stack { int num_paths; @@ -854,6 +864,12 @@ struct net_device_path_stack { struct net_device_path_ctx { const struct net_device *dev; const u8 *daddr; + + int num_vlans; + struct { + u16 id; + __be16 proto; + } vlan[NET_DEVICE_PATH_VLAN_MAX]; }; enum tc_setup_type { --- a/net/8021q/vlan_dev.c +++ b/net/8021q/vlan_dev.c @@ -777,6 +777,12 @@ static int vlan_dev_fill_forward_path(st path->encap.proto = vlan->vlan_proto; path->dev = ctx->dev; ctx->dev = vlan->real_dev; + if (ctx->num_vlans >= ARRAY_SIZE(ctx->vlan)) + return -ENOSPC; + + ctx->vlan[ctx->num_vlans].id = vlan->vlan_id; + ctx->vlan[ctx->num_vlans].proto = vlan->vlan_proto; + ctx->num_vlans++; return 0; } --- a/net/bridge/br_device.c +++ b/net/bridge/br_device.c @@ -409,7 +409,10 @@ static int br_fill_forward_path(struct n return -1; br = netdev_priv(ctx->dev); - f = br_fdb_find_rcu(br, ctx->daddr, 0); + + br_vlan_fill_forward_path_pvid(br, ctx, path); + + f = br_fdb_find_rcu(br, ctx->daddr, path->bridge.vlan_id); if (!f || !f->dst) return -1; @@ -417,10 +420,28 @@ static int br_fill_forward_path(struct n if (!dst) return -1; + if (br_vlan_fill_forward_path_mode(br, dst, path)) + return -1; + path->type = DEV_PATH_BRIDGE; path->dev = dst->br->dev; ctx->dev = dst->dev; + switch (path->bridge.vlan_mode) { + case DEV_PATH_BR_VLAN_TAG: + if (ctx->num_vlans >= ARRAY_SIZE(ctx->vlan)) + return -ENOSPC; + ctx->vlan[ctx->num_vlans].id = path->bridge.vlan_id; + ctx->vlan[ctx->num_vlans].proto = path->bridge.vlan_proto; + ctx->num_vlans++; + break; + case DEV_PATH_BR_VLAN_UNTAG: + ctx->num_vlans--; + break; + case DEV_PATH_BR_VLAN_KEEP: + break; + } + return 0; } --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -1095,6 +1095,13 @@ void br_vlan_notify(const struct net_bri bool br_vlan_can_enter_range(const struct net_bridge_vlan *v_curr, const struct net_bridge_vlan *range_end); +void br_vlan_fill_forward_path_pvid(struct net_bridge *br, + struct net_device_path_ctx *ctx, + struct net_device_path *path); +int br_vlan_fill_forward_path_mode(struct net_bridge *br, + struct net_bridge_port *dst, + struct net_device_path *path); + static inline struct net_bridge_vlan_group *br_vlan_group( const struct net_bridge *br) { @@ -1252,6 +1259,19 @@ static inline int nbp_get_num_vlan_infos { return 0; } + +static inline void br_vlan_fill_forward_path_pvid(struct net_bridge *br, + struct net_device_path_ctx *ctx, + struct net_device_path *path) +{ +} + +static inline int br_vlan_fill_forward_path_mode(struct net_bridge *br, + struct net_bridge_port *dst, + struct net_device_path *path) +{ + return 0; +} static inline struct net_bridge_vlan_group *br_vlan_group( const struct net_bridge *br) --- a/net/bridge/br_vlan.c +++ b/net/bridge/br_vlan.c @@ -1327,6 +1327,59 @@ int br_vlan_get_pvid_rcu(const struct ne } EXPORT_SYMBOL_GPL(br_vlan_get_pvid_rcu); +void br_vlan_fill_forward_path_pvid(struct net_bridge *br, + struct net_device_path_ctx *ctx, + struct net_device_path *path) +{ + struct net_bridge_vlan_group *vg; + int idx = ctx->num_vlans - 1; + u16 vid; + + path->bridge.vlan_mode = DEV_PATH_BR_VLAN_KEEP; + + if (!br_opt_get(br, BROPT_VLAN_ENABLED)) + return; + + vg = br_vlan_group(br); + + if (idx >= 0 && + ctx->vlan[idx].proto == br->vlan_proto) { + vid = ctx->vlan[idx].id; + } else { + path->bridge.vlan_mode = DEV_PATH_BR_VLAN_TAG; + vid = br_get_pvid(vg); + } + + path->bridge.vlan_id = vid; + path->bridge.vlan_proto = br->vlan_proto; +} + +int br_vlan_fill_forward_path_mode(struct net_bridge *br, + struct net_bridge_port *dst, + struct net_device_path *path) +{ + struct net_bridge_vlan_group *vg; + struct net_bridge_vlan *v; + + if (!br_opt_get(br, BROPT_VLAN_ENABLED)) + return 0; + + vg = nbp_vlan_group_rcu(dst); + v = br_vlan_find(vg, path->bridge.vlan_id); + if (!v || !br_vlan_should_use(v)) + return -EINVAL; + + if (!(v->flags & BRIDGE_VLAN_INFO_UNTAGGED)) + return 0; + + if (path->bridge.vlan_mode == DEV_PATH_BR_VLAN_TAG) + path->bridge.vlan_mode = DEV_PATH_BR_VLAN_KEEP; + else + path->bridge.vlan_mode = DEV_PATH_BR_VLAN_UNTAG; + + return 0; +} + int br_vlan_get_info(const struct net_device *dev, u16 vid, struct bridge_vlan_info *p_vinfo) {