bridge: Port Hy-Fi bridging hooks

Changes to port Hy-Fi bridging hooks and to export
br_fdb_find_rcu symbol.

Change-Id: Ife2a9ac76e02fff56b8c4acaa97794df7e98863d
Signed-off-by: Muthuchamy Kumar <quic_muthucha@quicinc.com>
Signed-off-by: Pooventhiran G <quic_pooventh@quicinc.com>

include/linux/if_bridge.h

@@ -50,6 +50,11 @@ struct br_ip_list {
 
 #define BR_DEFAULT_AGEING_TIME	(300 * HZ)
 
+//Handle HYFI_BRIDGING hooks related stuffs, only if HYFI_BRIDGE_HOOKS is defined
+#ifdef CONFIG_HYFI_BRIDGE_HOOKS
+struct net_bridge_port;
+#endif
+
 extern void brioctl_set(int (*ioctl_hook)(struct net *, unsigned int, void __user *));
 
 #ifdef CONFIG_ENABLE_SFE
@@ -151,4 +156,11 @@ br_port_flag_is_set(const struct net_device *dev, unsigned long flag)
 }
 #endif
 
+#ifdef CONFIG_HYFI_BRIDGE_HOOKS
+typedef void (br_notify_hook_t)(int group, int event, const void *ptr);
+extern br_notify_hook_t __rcu *br_notify_hook;
+typedef int (br_multicast_handle_hook_t)(const struct net_bridge_port *src,
+		struct sk_buff *skb);
+extern br_multicast_handle_hook_t __rcu *br_multicast_handle_hook;
+#endif
 #endif

net/bridge/Kconfig

@@ -61,3 +61,15 @@ config BRIDGE_VLAN_FILTERING
 	  Say N to exclude this support and reduce the binary size.
 
 	  If unsure, say Y.
+
+config HYFI_BRIDGE_HOOKS
+	bool "Port Hy-Fi Bridging Hooks"
+	depends on BRIDGE
+	depends on QGKI
+	default y
+	help
+	  If you say Y here, then the Port Hy-Fi Bridging Hooks will be enabled.
+
+	  Say N to exclude this support.
+
+	  If unsure, say Y.

net/bridge/br.c

@@ -394,6 +394,12 @@ static void __exit br_deinit(void)
 	br_fdb_fini();
 }
 
+#ifdef CONFIG_HYFI_BRIDGE_HOOKS
+/* Hook for bridge event notifications */
+br_notify_hook_t __rcu *br_notify_hook __read_mostly;
+EXPORT_SYMBOL(br_notify_hook);
+#endif
+
 module_init(br_init)
 module_exit(br_deinit)
 MODULE_LICENSE("GPL");

net/bridge/br_device.c

@@ -81,6 +81,12 @@ netdev_tx_t br_dev_xmit(struct sk_buff *skb, struct net_device *dev)
 	if (is_broadcast_ether_addr(dest)) {
 		br_flood(br, skb, BR_PKT_BROADCAST, false, true);
 	} else if (is_multicast_ether_addr(dest)) {
+#ifdef CONFIG_HYFI_BRIDGE_HOOKS
+		br_multicast_handle_hook_t *multicast_handle_hook =
+			rcu_dereference(br_multicast_handle_hook);
+		if (!__br_get(multicast_handle_hook, true, NULL, skb))
+			goto out;
+#endif
 		if (unlikely(netpoll_tx_running(dev))) {
 			br_flood(br, skb, BR_PKT_MULTICAST, false, true);
 			goto out;

net/bridge/br_fdb.c

@@ -147,6 +147,10 @@ struct net_bridge_fdb_entry *br_fdb_find_rcu(struct net_bridge *br,
 	return fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
 }
 
+#ifdef CONFIG_HYFI_BRIDGE_HOOKS
+EXPORT_SYMBOL(br_fdb_find_rcu);
+#endif
+
 /* When a static FDB entry is added, the mac address from the entry is
  * added to the bridge private HW address list and all required ports
  * are then updated with the new information.
@@ -709,6 +713,9 @@ static void fdb_notify(struct net_bridge *br,
 		kfree_skb(skb);
 		goto errout;
 	}
+#ifdef CONFIG_HYFI_BRIDGE_HOOKS
+	__br_notify(RTNLGRP_NEIGH, type, fdb);
+#endif
 	rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
 	return;
 errout:

net/bridge/br_input.c

@@ -29,7 +29,13 @@ br_netif_receive_skb(struct net *net, struct sock *sk, struct sk_buff *skb)
 	return netif_receive_skb(skb);
 }
 
-static int br_pass_frame_up(struct sk_buff *skb)
+#ifdef CONFIG_HYFI_BRIDGE_HOOKS
+/* Hook for external Multicast handler */
+br_multicast_handle_hook_t __rcu *br_multicast_handle_hook __read_mostly;
+EXPORT_SYMBOL(br_multicast_handle_hook);
+#endif
+
+int br_pass_frame_up(struct sk_buff *skb)
 {
 	struct net_device *indev, *brdev = BR_INPUT_SKB_CB(skb)->brdev;
 	struct net_bridge *br = netdev_priv(brdev);
@@ -66,6 +72,10 @@ static int br_pass_frame_up(struct sk_buff *skb)
 		       br_netif_receive_skb);
 }
 
+#ifdef CONFIG_HYFI_BRIDGE_HOOKS
+EXPORT_SYMBOL(br_pass_frame_up);
+#endif
+
 /* note: already called with rcu_read_lock */
 int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
 {
@@ -75,6 +85,9 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb
 	struct net_bridge_mdb_entry *mdst;
 	bool local_rcv, mcast_hit = false;
 	struct net_bridge *br;
+#ifdef CONFIG_HYFI_BRIDGE_HOOKS
+	br_multicast_handle_hook_t *multicast_handle_hook;
+#endif
 	u16 vid = 0;
 
 	if (!p || p->state == BR_STATE_DISABLED)
@@ -128,6 +141,11 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb
 
 	switch (pkt_type) {
 	case BR_PKT_MULTICAST:
+#ifdef CONFIG_HYFI_BRIDGE_HOOKS
+		multicast_handle_hook = rcu_dereference(br_multicast_handle_hook);
+		if (!__br_get(multicast_handle_hook, true, p, skb))
+			goto out;
+#endif
 		mdst = br_mdb_get(br, skb, vid);
 		if ((mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) &&
 		    br_multicast_querier_exists(br, eth_hdr(skb))) {

net/bridge/br_netlink.c

@@ -499,6 +499,9 @@ void br_ifinfo_notify(int event, const struct net_bridge *br,
 		kfree_skb(skb);
 		goto errout;
 	}
+#ifdef CONFIG_HYFI_BRIDGE_HOOKS
+	__br_notify(RTNLGRP_LINK, event, port);
+#endif
 	rtnl_notify(skb, net, 0, RTNLGRP_LINK, NULL, GFP_ATOMIC);
 	return;
 errout:

net/bridge/br_private.h

@@ -18,6 +18,9 @@
 #include <linux/if_vlan.h>
 #include <linux/rhashtable.h>
 #include <linux/refcount.h>
+#ifdef CONFIG_HYFI_BRIDGE_HOOKS
+#include <linux/export.h>
+#endif
 
 #define BR_HASH_BITS 8
 #define BR_HASH_SIZE (1 << BR_HASH_BITS)
@@ -625,6 +628,9 @@ void br_manage_promisc(struct net_bridge *br);
 int nbp_backup_change(struct net_bridge_port *p, struct net_device *backup_dev);
 
 /* br_input.c */
+#ifdef CONFIG_HYFI_BRIDGE_HOOKS
+int br_pass_frame_up(struct sk_buff *skb);
+#endif
 int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb);
 rx_handler_result_t br_handle_frame(struct sk_buff **pskb);
 
@@ -1266,4 +1272,17 @@ void br_do_proxy_suppress_arp(struct sk_buff *skb, struct net_bridge *br,
 void br_do_suppress_nd(struct sk_buff *skb, struct net_bridge *br,
 		       u16 vid, struct net_bridge_port *p, struct nd_msg *msg);
 struct nd_msg *br_is_nd_neigh_msg(struct sk_buff *skb, struct nd_msg *m);
+#ifdef CONFIG_HYFI_BRIDGE_HOOKS
+#define __br_get(__hook, __default, __args ...) \
+		({ typeof(__hook) HOOK_ = (__hook);     \
+		(HOOK_ ? (HOOK_(__args)) : (__default)); })
+
+static inline void __br_notify(int group, int type, const void *data)
+{
+	br_notify_hook_t *notify_hook = rcu_dereference(br_notify_hook);
+
+	if (notify_hook)
+		notify_hook(group, type, data);
+}
+#endif
 #endif