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Diffstat (limited to 'net/ipv4/arp.c')
-rw-r--r--net/ipv4/arp.c58
1 files changed, 51 insertions, 7 deletions
diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c
index c95cd93acf2..c4dd1354280 100644
--- a/net/ipv4/arp.c
+++ b/net/ipv4/arp.c
@@ -70,6 +70,7 @@
* bonding can change the skb before
* sending (e.g. insert 8021q tag).
* Harald Welte : convert to make use of jenkins hash
+ * Jesper D. Brouer: Proxy ARP PVLAN RFC 3069 support.
*/
#include <linux/module.h>
@@ -524,12 +525,15 @@ int arp_bind_neighbour(struct dst_entry *dst)
/*
* Check if we can use proxy ARP for this path
*/
-
-static inline int arp_fwd_proxy(struct in_device *in_dev, struct rtable *rt)
+static inline int arp_fwd_proxy(struct in_device *in_dev,
+ struct net_device *dev, struct rtable *rt)
{
struct in_device *out_dev;
int imi, omi = -1;
+ if (rt->u.dst.dev == dev)
+ return 0;
+
if (!IN_DEV_PROXY_ARP(in_dev))
return 0;
@@ -548,6 +552,43 @@ static inline int arp_fwd_proxy(struct in_device *in_dev, struct rtable *rt)
}
/*
+ * Check for RFC3069 proxy arp private VLAN (allow to send back to same dev)
+ *
+ * RFC3069 supports proxy arp replies back to the same interface. This
+ * is done to support (ethernet) switch features, like RFC 3069, where
+ * the individual ports are not allowed to communicate with each
+ * other, BUT they are allowed to talk to the upstream router. As
+ * described in RFC 3069, it is possible to allow these hosts to
+ * communicate through the upstream router, by proxy_arp'ing.
+ *
+ * RFC 3069: "VLAN Aggregation for Efficient IP Address Allocation"
+ *
+ * This technology is known by different names:
+ * In RFC 3069 it is called VLAN Aggregation.
+ * Cisco and Allied Telesyn call it Private VLAN.
+ * Hewlett-Packard call it Source-Port filtering or port-isolation.
+ * Ericsson call it MAC-Forced Forwarding (RFC Draft).
+ *
+ */
+static inline int arp_fwd_pvlan(struct in_device *in_dev,
+ struct net_device *dev, struct rtable *rt,
+ __be32 sip, __be32 tip)
+{
+ /* Private VLAN is only concerned about the same ethernet segment */
+ if (rt->u.dst.dev != dev)
+ return 0;
+
+ /* Don't reply on self probes (often done by windowz boxes)*/
+ if (sip == tip)
+ return 0;
+
+ if (IN_DEV_PROXY_ARP_PVLAN(in_dev))
+ return 1;
+ else
+ return 0;
+}
+
+/*
* Interface to link layer: send routine and receive handler.
*/
@@ -833,8 +874,11 @@ static int arp_process(struct sk_buff *skb)
}
goto out;
} else if (IN_DEV_FORWARD(in_dev)) {
- if (addr_type == RTN_UNICAST && rt->u.dst.dev != dev &&
- (arp_fwd_proxy(in_dev, rt) || pneigh_lookup(&arp_tbl, net, &tip, dev, 0))) {
+ if (addr_type == RTN_UNICAST &&
+ (arp_fwd_proxy(in_dev, dev, rt) ||
+ arp_fwd_pvlan(in_dev, dev, rt, sip, tip) ||
+ pneigh_lookup(&arp_tbl, net, &tip, dev, 0)))
+ {
n = neigh_event_ns(&arp_tbl, sha, &sip, dev);
if (n)
neigh_release(n);
@@ -863,7 +907,8 @@ static int arp_process(struct sk_buff *skb)
devices (strip is candidate)
*/
if (n == NULL &&
- arp->ar_op == htons(ARPOP_REPLY) &&
+ (arp->ar_op == htons(ARPOP_REPLY) ||
+ (arp->ar_op == htons(ARPOP_REQUEST) && tip == sip)) &&
inet_addr_type(net, sip) == RTN_UNICAST)
n = __neigh_lookup(&arp_tbl, &sip, dev, 1);
}
@@ -1239,8 +1284,7 @@ void __init arp_init(void)
dev_add_pack(&arp_packet_type);
arp_proc_init();
#ifdef CONFIG_SYSCTL
- neigh_sysctl_register(NULL, &arp_tbl.parms, NET_IPV4,
- NET_IPV4_NEIGH, "ipv4", NULL);
+ neigh_sysctl_register(NULL, &arp_tbl.parms, "ipv4", NULL);
#endif
register_netdevice_notifier(&arp_netdev_notifier);
}