1 files changed, 115 insertions, 6 deletions

diff --git a/net/batman-adv/bridge_loop_avoidance.c b/net/batman-adv/bridge_loop_avoidance.c
index 4f6b44a5b12..1cf18ac44ba 100644
--- a/net/batman-adv/bridge_loop_avoidance.c
+++ b/net/batman-adv/bridge_loop_avoidance.c
@@ -33,7 +33,6 @@
 #include <net/arp.h>
 #include <linux/if_vlan.h>
 
-static const uint8_t claim_dest[6] = {0xff, 0x43, 0x05, 0x00, 0x00, 0x00};
 static const uint8_t announce_mac[4] = {0x43, 0x05, 0x43, 0x05};
 
 static void bla_periodic_work(struct work_struct *work);
@@ -265,7 +264,8 @@ static void bla_send_claim(struct bat_priv *bat_priv, uint8_t *mac,
         if (!primary_if)
                 return;
 
-        memcpy(&local_claim_dest, claim_dest, sizeof(local_claim_dest));
+        memcpy(&local_claim_dest, &bat_priv->claim_dest,
+               sizeof(local_claim_dest));
         local_claim_dest.type = claimtype;
 
         soft_iface = primary_if->soft_iface;
@@ -282,6 +282,7 @@ static void bla_send_claim(struct bat_priv *bat_priv, uint8_t *mac,
                          primary_if->net_dev->dev_addr,
                          /* HW DST: FF:43:05:XX:00:00
                           * with XX   = claim type
+                          * and YY:YY = group id
                           */
                          (uint8_t *)&local_claim_dest);
 
@@ -734,6 +735,86 @@ static int handle_claim(struct bat_priv *bat_priv,
 
 /**
  * @bat_priv: the bat priv with all the soft interface information
+ * @bat_priv: the bat priv with all the soft interface information
+ * @hw_src: the Hardware source in the ARP Header
+ * @hw_dst: the Hardware destination in the ARP Header
+ * @ethhdr: pointer to the Ethernet header of the claim frame
+ *
+ * checks if it is a claim packet and if its on the same group.
+ * This function also applies the group ID of the sender
+ * if it is in the same mesh.
+ *
+ * returns:
+ *      2  - if it is a claim packet and on the same group
+ *      1  - if is a claim packet from another group
+ *      0  - if it is not a claim packet
+ */
+static int check_claim_group(struct bat_priv *bat_priv,
+                             struct hard_iface *primary_if,
+                             uint8_t *hw_src, uint8_t *hw_dst,
+                             struct ethhdr *ethhdr)
+{
+        uint8_t *backbone_addr;
+        struct orig_node *orig_node;
+        struct bla_claim_dst *bla_dst, *bla_dst_own;
+
+        bla_dst = (struct bla_claim_dst *)hw_dst;
+        bla_dst_own = &bat_priv->claim_dest;
+
+        /* check if it is a claim packet in general */
+        if (memcmp(bla_dst->magic, bla_dst_own->magic,
+                   sizeof(bla_dst->magic)) != 0)
+                return 0;
+
+        /* if announcement packet, use the source,
+         * otherwise assume it is in the hw_src
+         */
+        switch (bla_dst->type) {
+        case CLAIM_TYPE_ADD:
+                backbone_addr = hw_src;
+                break;
+        case CLAIM_TYPE_REQUEST:
+        case CLAIM_TYPE_ANNOUNCE:
+        case CLAIM_TYPE_DEL:
+                backbone_addr = ethhdr->h_source;
+                break;
+        default:
+                return 0;
+        }
+
+        /* don't accept claim frames from ourselves */
+        if (compare_eth(backbone_addr, primary_if->net_dev->dev_addr))
+                return 0;
+
+        /* if its already the same group, it is fine. */
+        if (bla_dst->group == bla_dst_own->group)
+                return 2;
+
+        /* lets see if this originator is in our mesh */
+        orig_node = orig_hash_find(bat_priv, backbone_addr);
+
+        /* dont accept claims from gateways which are not in
+         * the same mesh or group.
+         */
+        if (!orig_node)
+                return 1;
+
+        /* if our mesh friends mac is bigger, use it for ourselves. */
+        if (ntohs(bla_dst->group) > ntohs(bla_dst_own->group)) {
+                bat_dbg(DBG_BLA, bat_priv,
+                        "taking other backbones claim group: %04x\n",
+                        ntohs(bla_dst->group));
+                bla_dst_own->group = bla_dst->group;
+        }
+
+        orig_node_free_ref(orig_node);
+
+        return 2;
+}
+
+
+/**
+ * @bat_priv: the bat priv with all the soft interface information
  * @skb: the frame to be checked
  *
  * Check if this is a claim frame, and process it accordingly.
@@ -753,6 +834,7 @@ static int bla_process_claim(struct bat_priv *bat_priv,
         uint16_t proto;
         int headlen;
         short vid = -1;
+        int ret;
 
         ethhdr = (struct ethhdr *)skb_mac_header(skb);
 
@@ -796,8 +878,14 @@ static int bla_process_claim(struct bat_priv *bat_priv,
         bla_dst = (struct bla_claim_dst *)hw_dst;
 
         /* check if it is a claim frame. */
-        if (memcmp(hw_dst, claim_dest, 3) != 0)
-                return 0;
+        ret = check_claim_group(bat_priv, primary_if, hw_src, hw_dst, ethhdr);
+        if (ret == 1)
+                bat_dbg(DBG_BLA, bat_priv,
+                        "bla_process_claim(): received a claim frame from another group. From: %pM on vid %d ...(hw_src %pM, hw_dst %pM)\n",
+                        ethhdr->h_source, vid, hw_src, hw_dst);
+
+        if (ret < 2)
+                return ret;
 
         /* become a backbone gw ourselves on this vlan if not happened yet */
         bla_update_own_backbone_gw(bat_priv, primary_if, vid);
@@ -944,6 +1032,10 @@ void bla_update_orig_address(struct bat_priv *bat_priv,
         struct hashtable_t *hash;
         int i;
 
+        /* reset bridge loop avoidance group id */
+        bat_priv->claim_dest.group =
+                htons(crc16(0, primary_if->net_dev->dev_addr, ETH_ALEN));
+
         if (!oldif) {
                 bla_purge_claims(bat_priv, NULL, 1);
                 bla_purge_backbone_gw(bat_priv, 1);
@@ -1042,9 +1134,24 @@ out:
 int bla_init(struct bat_priv *bat_priv)
 {
         int i;
+        uint8_t claim_dest[ETH_ALEN] = {0xff, 0x43, 0x05, 0x00, 0x00, 0x00};
+        struct hard_iface *primary_if;
 
         bat_dbg(DBG_BLA, bat_priv, "bla hash registering\n");
 
+        /* setting claim destination address */
+        memcpy(&bat_priv->claim_dest.magic, claim_dest, 3);
+        bat_priv->claim_dest.type = 0;
+        primary_if = primary_if_get_selected(bat_priv);
+        if (primary_if) {
+                bat_priv->claim_dest.group =
+                        htons(crc16(0, primary_if->net_dev->dev_addr,
+                                    ETH_ALEN));
+                hardif_free_ref(primary_if);
+        } else {
+                bat_priv->claim_dest.group = 0; /* will be set later */
+        }
+
         /* initialize the duplicate list */
         for (i = 0; i < DUPLIST_SIZE; i++)
                 bat_priv->bcast_duplist[i].entrytime =
@@ -1448,8 +1555,10 @@ int bla_claim_table_seq_print_text(struct seq_file *seq, void *offset)
                 goto out;
         }
 
-        seq_printf(seq, "Claims announced for the mesh %s (orig %pM)\n",
-                   net_dev->name, primary_if->net_dev->dev_addr);
+        seq_printf(seq,
+                   "Claims announced for the mesh %s (orig %pM, group id %04x)\n",
+                   net_dev->name, primary_if->net_dev->dev_addr,
+                   ntohs(bat_priv->claim_dest.group));
         seq_printf(seq, "   %-17s    %-5s    %-17s [o] (%-4s)\n",
                    "Client", "VID", "Originator", "CRC");
         for (i = 0; i < hash->size; i++) {