@@ -27,6 +27,14 @@ struct ip_tunnel {
__u32 o_seqno; /* The last output seqno */
int hlen; /* Precalculated GRE header length */
int mlink;
+#ifdef CONFIG_NET_IPGRE_BRIDGE
+#define GRETAP_BR_HASH_BITS 8
+#define GRETAP_BR_HASH_SIZE (1 << GRETAP_BR_HASH_BITS)
+ struct hlist_head hash[GRETAP_BR_HASH_SIZE];
+ spinlock_t hash_lock;
+ unsigned long ageing_time;
+ struct timer_list gc_timer;
+#endif
struct ip_tunnel_parm parms;
@@ -211,6 +211,15 @@ config NET_IPGRE_BROADCAST
Network), but can be distributed all over the Internet. If you want
to do that, say Y here and to "IP multicast routing" below.
+config NET_IPGRE_BRIDGE
+ bool "IP: Ethernet over multipoint GRE over IP"
+ depends on IP_MULTICAST && NET_IPGRE && NET_IPGRE_BROADCAST
+ help
+ Allows you to use multipoint GRE VPN as virtual switch and interconnect
+ several L2 endpoints over L3 routed infrastructure. It is useful for
+ creating multipoint L2 VPNs which can be later used inside bridge
+ interfaces If you want to use. GRE multipoint L2 VPN feature say Y.
+
config IP_MROUTE
bool "IP: multicast routing"
depends on IP_MULTICAST
@@ -52,6 +52,11 @@
#include <net/ip6_route.h>
#endif
+#ifdef CONFIG_NET_IPGRE_BRIDGE
+#include <linux/jhash.h>
+#include <asm/unaligned.h>
+#endif
+
/*
Problems & solutions
--------------------
@@ -134,6 +139,172 @@ struct ipgre_net {
struct net_device *fb_tunnel_dev;
};
+#ifdef CONFIG_NET_IPGRE_BRIDGE
+ /*
+ * This part of code includes codes to enable L2 ethernet
+ * switch virtualization over IP routed infrastructure with
+ * utilization of multicast capable endpoint using Ethernet
+ * over GRE
+ *
+ * Author: Stefan Gula
+ * Signed-off-by: Stefan Gula <steweg@gmail.com>
+ */
+struct ipgre_tap_bridge_entry {
+ struct hlist_node hlist;
+ __be32 raddr;
+ unsigned char addr[ETH_ALEN];
+ unsigned long updated;
+ struct rcu_head rcu;
+};
+
+static u32 ipgre_salt __read_mostly;
+
+static inline int ipgre_tap_bridge_hash(const unsigned char *mac)
+{
+ u32 key = get_unaligned((u32 *)(mac + 2));
+
+ return jhash_1word(key, ipgre_salt) & (GRETAP_BR_HASH_SIZE - 1);
+}
+
+static inline int ipgre_tap_bridge_has_expired(const struct ip_tunnel *tunnel,
+ const struct ipgre_tap_bridge_entry *entry)
+{
+ return time_before_eq(entry->updated + tunnel->ageing_time,
+ jiffies);
+}
+
+static inline void ipgre_tap_bridge_delete(struct ipgre_tap_bridge_entry *entry)
+{
+ hlist_del_rcu(&entry->hlist);
+ kfree_rcu(entry, rcu);
+}
+
+static void ipgre_tap_bridge_cleanup(unsigned long _data)
+{
+ struct ip_tunnel *tunnel = (struct ip_tunnel *)_data;
+ unsigned long delay = tunnel->ageing_time;
+ unsigned long next_timer = jiffies + tunnel->ageing_time;
+ int i;
+
+ spin_lock(&tunnel->hash_lock);
+ for (i = 0; i < GRETAP_BR_HASH_SIZE; i++) {
+ struct ipgre_tap_bridge_entry *entry;
+ struct hlist_node *h, *n;
+
+ hlist_for_each_entry_safe(entry, h, n,
+ &tunnel->hash[i], hlist)
+ {
+ unsigned long this_timer;
+ this_timer = entry->updated + delay;
+ if (time_before_eq(this_timer, jiffies))
+ ipgre_tap_bridge_delete(entry);
+ else if (time_before(this_timer, next_timer))
+ next_timer = this_timer;
+ }
+ }
+ spin_unlock(&tunnel->hash_lock);
+ mod_timer(&tunnel->gc_timer, round_jiffies_up(next_timer));
+}
+
+static void ipgre_tap_bridge_flush(struct ip_tunnel *tunnel)
+{
+ int i;
+
+ spin_lock_bh(&tunnel->hash_lock);
+ for (i = 0; i < GRETAP_BR_HASH_SIZE; i++) {
+ struct ipgre_tap_bridge_entry *entry;
+ struct hlist_node *h, *n;
+
+ hlist_for_each_entry_safe(entry, h, n,
+ &tunnel->hash[i], hlist)
+ {
+ ipgre_tap_bridge_delete(entry);
+ }
+ }
+ spin_unlock_bh(&tunnel->hash_lock);
+}
+
+static struct ipgre_tap_bridge_entry *__ipgre_tap_bridge_get(
+ struct ip_tunnel *tunnel, const unsigned char *addr)
+{
+ struct hlist_node *h;
+ struct ipgre_tap_bridge_entry *entry;
+
+ hlist_for_each_entry_rcu(entry, h,
+ &tunnel->hash[ipgre_tap_bridge_hash(addr)], hlist) {
+ if (!compare_ether_addr(entry->addr, addr)) {
+ if (unlikely(ipgre_tap_bridge_has_expired(tunnel,
+ entry)))
+ break;
+ return entry;
+ }
+ }
+
+ return NULL;
+}
+
+static struct ipgre_tap_bridge_entry *ipgre_tap_bridge_find(
+ struct hlist_head *head,
+ const unsigned char *addr)
+{
+ struct hlist_node *h;
+ struct ipgre_tap_bridge_entry *entry;
+
+ hlist_for_each_entry(entry, h, head, hlist) {
+ if (!compare_ether_addr(entry->addr, addr))
+ return entry;
+ }
+ return NULL;
+}
+
+
+static struct ipgre_tap_bridge_entry *ipgre_tap_bridge_find_rcu(
+ struct hlist_head *head,
+ const unsigned char *addr)
+{
+ struct hlist_node *h;
+ struct ipgre_tap_bridge_entry *entry;
+
+ hlist_for_each_entry_rcu(entry, h, head, hlist) {
+ if (!compare_ether_addr(entry->addr, addr))
+ return entry;
+ }
+ return NULL;
+}
+
+static struct ipgre_tap_bridge_entry *ipgre_tap_bridge_create(
+ struct hlist_head *head,
+ u32 source,
+ const unsigned char *addr)
+{
+ struct ipgre_tap_bridge_entry *entry;
+
+ entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
+ if (entry) {
+ memcpy(entry->addr, addr, ETH_ALEN);
+ entry->raddr = source;
+ entry->updated = jiffies;
+ hlist_add_head_rcu(&entry->hlist, head);
+ }
+ return entry;
+}
+
+static __be32 ipgre_tap_bridge_get_raddr(struct ip_tunnel *tunnel,
+ const unsigned char *addr)
+{
+ __be32 raddr = 0;
+ struct ipgre_tap_bridge_entry *entry;
+
+ rcu_read_lock();
+ entry = __ipgre_tap_bridge_get(tunnel, addr);
+ if (entry)
+ raddr = entry->raddr;
+ rcu_read_unlock();
+
+ return raddr;
+}
+
+#endif
/* Tunnel hash table */
/*
@@ -562,6 +733,12 @@ static int ipgre_rcv(struct sk_buff *skb)
struct ip_tunnel *tunnel;
int offset = 4;
__be16 gre_proto;
+#ifdef CONFIG_NET_IPGRE_BRIDGE
+ __be32 orig_source;
+ struct hlist_head *head;
+ struct ipgre_tap_bridge_entry *entry;
+ const struct ethhdr *tethhdr;
+#endif
if (!pskb_may_pull(skb, 16))
goto drop_nolock;
@@ -659,10 +836,38 @@ static int ipgre_rcv(struct sk_buff *skb)
tunnel->dev->stats.rx_errors++;
goto drop;
}
-
iph = ip_hdr(skb);
+#ifdef CONFIG_NET_IPGRE_BRIDGE
+ orig_source = iph->saddr;
+#endif
skb->protocol = eth_type_trans(skb, tunnel->dev);
skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
+#ifdef CONFIG_NET_IPGRE_BRIDGE
+ if (ipv4_is_multicast(tunnel->parms.iph.daddr)) {
+ tethhdr = eth_hdr(skb);
+ if (!is_multicast_ether_addr(
+ tethhdr->h_source)) {
+ head = &tunnel->hash[
+ ipgre_tap_bridge_hash(
+ tethhdr->h_source)];
+ entry = ipgre_tap_bridge_find_rcu(head,
+ tethhdr->h_source);
+ if (likely(entry)) {
+ entry->raddr = orig_source;
+ entry->updated = jiffies;
+ } else {
+ spin_lock(&tunnel->hash_lock);
+ if (!ipgre_tap_bridge_find(head,
+ tethhdr->h_source))
+ ipgre_tap_bridge_create(
+ head,
+ orig_source,
+ tethhdr->h_source);
+ spin_unlock(&tunnel->hash_lock);
+ }
+ }
+ }
+#endif
}
tstats = this_cpu_ptr(tunnel->dev->tstats);
@@ -702,7 +907,7 @@ static netdev_tx_t ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev
struct iphdr *iph; /* Our new IP header */
unsigned int max_headroom; /* The extra header space needed */
int gre_hlen;
- __be32 dst;
+ __be32 dst = 0;
int mtu;
if (dev->type == ARPHRD_ETHER)
@@ -716,7 +921,15 @@ static netdev_tx_t ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev
tiph = &tunnel->parms.iph;
}
- if ((dst = tiph->daddr) == 0) {
+#ifdef CONFIG_NET_IPGRE_BRIDGE
+ if ((dev->type == ARPHRD_ETHER) &&
+ ipv4_is_multicast(tunnel->parms.iph.daddr))
+ dst = ipgre_tap_bridge_get_raddr(tunnel,
+ ((struct ethhdr *)skb->data)->h_dest);
+#endif
+ if (dst == 0)
+ dst = tiph->daddr;
+ if (dst == 0) {
/* NBMA tunnel */
if (skb_dst(skb) == NULL) {
@@ -1211,6 +1424,16 @@ static int ipgre_open(struct net_device *dev)
return -EADDRNOTAVAIL;
t->mlink = dev->ifindex;
ip_mc_inc_group(__in_dev_get_rtnl(dev), t->parms.iph.daddr);
+#ifdef CONFIG_NET_IPGRE_BRIDGE
+ if (t->dev->type == ARPHRD_ETHER) {
+ INIT_HLIST_HEAD(t->hash);
+ spin_lock_init(&t->hash_lock);
+ t->ageing_time = 300 * HZ;
+ setup_timer(&t->gc_timer, ipgre_tap_bridge_cleanup,
+ (unsigned long) t);
+ mod_timer(&t->gc_timer, jiffies + t->ageing_time);
+ }
+#endif
}
return 0;
}
@@ -1221,6 +1444,12 @@ static int ipgre_close(struct net_device *dev)
if (ipv4_is_multicast(t->parms.iph.daddr) && t->mlink) {
struct in_device *in_dev;
+#ifdef CONFIG_NET_IPGRE_BRIDGE
+ if (t->dev->type == ARPHRD_ETHER) {
+ ipgre_tap_bridge_flush(t);
+ del_timer_sync(&t->gc_timer);
+ }
+#endif
in_dev = inetdev_by_index(dev_net(dev), t->mlink);
if (in_dev)
ip_mc_dec_group(in_dev, t->parms.iph.daddr);
@@ -1707,6 +1936,9 @@ static int __init ipgre_init(void)
printk(KERN_INFO "GRE over IPv4 tunneling driver\n");
+#ifdef CONFIG_NET_IPGRE_BRIDGE
+ get_random_bytes(&ipgre_salt, sizeof(ipgre_salt));
+#endif
err = register_pernet_device(&ipgre_net_ops);
if (err < 0)
return err;