net: bridge: mdb: add support to extend add/del commands

Since the MDB add/del code expects an exact struct br_mdb_entry we can't
really add any extensions, thus add a new nested attribute at the level of
MDBA_SET_ENTRY called MDBA_SET_ENTRY_ATTRS which will be used to pass
all new options via netlink attributes. This patch doesn't change
anything functionally since the new attribute is not used yet, only
parsed.

Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/uapi/linux/if_bridge.h b/include/uapi/linux/if_bridge.h
index 75a2ac4..dc52f8c 100644 (file)
--- a/include/uapi/linux/if_bridge.h
+++ b/include/uapi/linux/if_bridge.h
@@ -530,10 +530,22 @@ struct br_mdb_entry {
 enum {
        MDBA_SET_ENTRY_UNSPEC,
        MDBA_SET_ENTRY,
+       MDBA_SET_ENTRY_ATTRS,
        __MDBA_SET_ENTRY_MAX,
 };
 #define MDBA_SET_ENTRY_MAX (__MDBA_SET_ENTRY_MAX - 1)
 
+/* [MDBA_SET_ENTRY_ATTRS] = {
+ *    [MDBE_ATTR_xxx]
+ *    ...
+ * }
+ */
+enum {
+       MDBE_ATTR_UNSPEC,
+       __MDBE_ATTR_MAX,
+};
+#define MDBE_ATTR_MAX (__MDBE_ATTR_MAX - 1)
+
 /* Embedded inside LINK_XSTATS_TYPE_BRIDGE */
 enum {
        BRIDGE_XSTATS_UNSPEC,

diff --git a/net/bridge/br_mdb.c b/net/bridge/br_mdb.c
index a1ff0a3..907df6d 100644 (file)
--- a/net/bridge/br_mdb.c
+++ b/net/bridge/br_mdb.c
@@ -670,9 +670,12 @@ static bool is_valid_mdb_entry(struct br_mdb_entry *entry,
        return true;
 }
 
+static const struct nla_policy br_mdbe_attrs_pol[MDBE_ATTR_MAX + 1] = {
+};
+
 static int br_mdb_parse(struct sk_buff *skb, struct nlmsghdr *nlh,
                        struct net_device **pdev, struct br_mdb_entry **pentry,
-                       struct netlink_ext_ack *extack)
+                       struct nlattr **mdb_attrs, struct netlink_ext_ack *extack)
 {
        struct net *net = sock_net(skb->sk);
        struct br_mdb_entry *entry;
@@ -719,6 +722,17 @@ static int br_mdb_parse(struct sk_buff *skb, struct nlmsghdr *nlh,
                return -EINVAL;
        *pentry = entry;
 
+       if (tb[MDBA_SET_ENTRY_ATTRS]) {
+               err = nla_parse_nested(mdb_attrs, MDBE_ATTR_MAX,
+                                      tb[MDBA_SET_ENTRY_ATTRS],
+                                      br_mdbe_attrs_pol, extack);
+               if (err)
+                       return err;
+       } else {
+               memset(mdb_attrs, 0,
+                      sizeof(struct nlattr *) * (MDBE_ATTR_MAX + 1));
+       }
+
        return 0;
 }
 
@@ -803,6 +817,7 @@ static int __br_mdb_add(struct net *net, struct net_bridge *br,
 static int br_mdb_add(struct sk_buff *skb, struct nlmsghdr *nlh,
                      struct netlink_ext_ack *extack)
 {
+       struct nlattr *mdb_attrs[MDBE_ATTR_MAX + 1];
        struct net *net = sock_net(skb->sk);
        struct net_bridge_vlan_group *vg;
        struct net_bridge_port *p = NULL;
@@ -812,7 +827,7 @@ static int br_mdb_add(struct sk_buff *skb, struct nlmsghdr *nlh,
        struct net_bridge *br;
        int err;
 
-       err = br_mdb_parse(skb, nlh, &dev, &entry, extack);
+       err = br_mdb_parse(skb, nlh, &dev, &entry, mdb_attrs, extack);
        if (err < 0)
                return err;
 
@@ -921,6 +936,7 @@ unlock:
 static int br_mdb_del(struct sk_buff *skb, struct nlmsghdr *nlh,
                      struct netlink_ext_ack *extack)
 {
+       struct nlattr *mdb_attrs[MDBE_ATTR_MAX + 1];
        struct net *net = sock_net(skb->sk);
        struct net_bridge_vlan_group *vg;
        struct net_bridge_port *p = NULL;
@@ -930,7 +946,7 @@ static int br_mdb_del(struct sk_buff *skb, struct nlmsghdr *nlh,
        struct net_bridge *br;
        int err;
 
-       err = br_mdb_parse(skb, nlh, &dev, &entry, extack);
+       err = br_mdb_parse(skb, nlh, &dev, &entry, mdb_attrs, extack);
        if (err < 0)
                return err;