+static void br_do_proxy_arp(struct sk_buff *skb, struct net_bridge *br,
+ u16 vid)
+{
+ struct net_device *dev = br->dev;
+ struct neighbour *n;
+ struct arphdr *parp;
+ u8 *arpptr, *sha;
+ __be32 sip, tip;
+
+ if (dev->flags & IFF_NOARP)
+ return;
+
+ if (!pskb_may_pull(skb, arp_hdr_len(dev))) {
+ dev->stats.tx_dropped++;
+ return;
+ }
+ parp = arp_hdr(skb);
+
+ if (parp->ar_pro != htons(ETH_P_IP) ||
+ parp->ar_op != htons(ARPOP_REQUEST) ||
+ parp->ar_hln != dev->addr_len ||
+ parp->ar_pln != 4)
+ return;
+
+ arpptr = (u8 *)parp + sizeof(struct arphdr);
+ sha = arpptr;
+ arpptr += dev->addr_len; /* sha */
+ memcpy(&sip, arpptr, sizeof(sip));
+ arpptr += sizeof(sip);
+ arpptr += dev->addr_len; /* tha */
+ memcpy(&tip, arpptr, sizeof(tip));
+
+ if (ipv4_is_loopback(tip) ||
+ ipv4_is_multicast(tip))
+ return;
+
+ n = neigh_lookup(&arp_tbl, &tip, dev);
+ if (n) {
+ struct net_bridge_fdb_entry *f;
+
+ if (!(n->nud_state & NUD_VALID)) {
+ neigh_release(n);
+ return;
+ }
+
+ f = __br_fdb_get(br, n->ha, vid);
+ if (f)
+ arp_send(ARPOP_REPLY, ETH_P_ARP, sip, skb->dev, tip,
+ sha, n->ha, sha);
+
+ neigh_release(n);
+ }
+}
+