batman-adv: filter ARP packets with invalid MAC addresses in DAT
authorMatthias Schiffer <mschiffer@universe-factory.net>
Thu, 24 Jan 2013 17:18:27 +0000 (18:18 +0100)
committerAntonio Quartulli <ordex@autistici.org>
Sun, 27 Jan 2013 13:02:39 +0000 (14:02 +0100)
We never want multicast MAC addresses in the Distributed ARP Table, so it's
best to completely ignore ARP packets containing them where we expect unicast
addresses.

Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Acked-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
net/batman-adv/distributed-arp-table.c

index ccb3c6c96ba77bc247b71bc385e89deb9e340940..183f97a86bb24c8099f4d3b7b7d4a5919d3432c4 100644 (file)
@@ -738,6 +738,7 @@ static uint16_t batadv_arp_get_type(struct batadv_priv *bat_priv,
        struct arphdr *arphdr;
        struct ethhdr *ethhdr;
        __be32 ip_src, ip_dst;
        struct arphdr *arphdr;
        struct ethhdr *ethhdr;
        __be32 ip_src, ip_dst;
+       uint8_t *hw_src, *hw_dst;
        uint16_t type = 0;
 
        /* pull the ethernet header */
        uint16_t type = 0;
 
        /* pull the ethernet header */
@@ -782,6 +783,18 @@ static uint16_t batadv_arp_get_type(struct batadv_priv *bat_priv,
            ipv4_is_zeronet(ip_dst) || ipv4_is_lbcast(ip_dst))
                goto out;
 
            ipv4_is_zeronet(ip_dst) || ipv4_is_lbcast(ip_dst))
                goto out;
 
+       hw_src = batadv_arp_hw_src(skb, hdr_size);
+       if (is_zero_ether_addr(hw_src) || is_multicast_ether_addr(hw_src))
+               goto out;
+
+       /* we don't care about the destination MAC address in ARP requests */
+       if (arphdr->ar_op != htons(ARPOP_REQUEST)) {
+               hw_dst = batadv_arp_hw_dst(skb, hdr_size);
+               if (is_zero_ether_addr(hw_dst) ||
+                   is_multicast_ether_addr(hw_dst))
+                       goto out;
+       }
+
        type = ntohs(arphdr->ar_op);
 out:
        return type;
        type = ntohs(arphdr->ar_op);
 out:
        return type;