[IPV4] ARP: Alloc acceptance of unsolicited ARP via netdevice sysctl.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 20 insertions, 10 deletions

diff --git a/include/linux/inetdevice.h b/include/linux/inetdevice.h
index fd7af86151b1..92297ff24e85 100644
--- a/include/linux/inetdevice.h
+++ b/include/linux/inetdevice.h
@@ -25,6 +25,7 @@ struct ipv4_devconf
         int     arp_filter;
         int     arp_announce;
         int     arp_ignore;
+        int     arp_accept;
         int     medium_id;
         int     no_xfrm;
         int     no_policy;
diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
index dfcf449afc7c..8754568a75d7 100644
--- a/include/linux/sysctl.h
+++ b/include/linux/sysctl.h
@@ -456,6 +456,7 @@ enum
         NET_IPV4_CONF_ARP_ANNOUNCE=18,
         NET_IPV4_CONF_ARP_IGNORE=19,
         NET_IPV4_CONF_PROMOTE_SECONDARIES=20,
+        NET_IPV4_CONF_ARP_ACCEPT=21,
         __NET_IPV4_CONF_MAX
 };
 
diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c
index accdefedfed7..041dadde31af 100644
--- a/net/ipv4/arp.c
+++ b/net/ipv4/arp.c
@@ -879,16 +879,16 @@ static int arp_process(struct sk_buff *skb)
 
         n = __neigh_lookup(&arp_tbl, &sip, dev, 0);
 
-#ifdef CONFIG_IP_ACCEPT_UNSOLICITED_ARP
-        /* Unsolicited ARP is not accepted by default.
-           It is possible, that this option should be enabled for some
-           devices (strip is candidate)
-         */
-        if (n == NULL &&
-            arp->ar_op == htons(ARPOP_REPLY) &&
-            inet_addr_type(sip) == RTN_UNICAST)
-                n = __neigh_lookup(&arp_tbl, &sip, dev, -1);
-#endif
+        if (ipv4_devconf.arp_accept) {
+                /* Unsolicited ARP is not accepted by default.
+                   It is possible, that this option should be enabled for some
+                   devices (strip is candidate)
+                 */
+                if (n == NULL &&
+                    arp->ar_op == htons(ARPOP_REPLY) &&
+                    inet_addr_type(sip) == RTN_UNICAST)
+                        n = __neigh_lookup(&arp_tbl, &sip, dev, -1);
+        }
 
         if (n) {
                 int state = NUD_REACHABLE;
diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
index 3ffa60dadc0c..44fdf1413e2c 100644
--- a/net/ipv4/devinet.c
+++ b/net/ipv4/devinet.c
@@ -1394,6 +1394,14 @@ static struct devinet_sysctl_table {
                         .proc_handler   = &proc_dointvec,
                 },
                 {
+                        .ctl_name       = NET_IPV4_CONF_ARP_ACCEPT,
+                        .procname       = "arp_accept",
+                        .data           = &ipv4_devconf.arp_accept,
+                        .maxlen         = sizeof(int),
+                        .mode           = 0644,
+                        .proc_handler   = &proc_dointvec,
+                },
+                {
                         .ctl_name       = NET_IPV4_CONF_NOXFRM,
                         .procname       = "disable_xfrm",
                         .data           = &ipv4_devconf.no_xfrm,