]> git.karo-electronics.de Git - karo-tx-linux.git/blobdiff - net/batman-adv/routing.c
Merge branch 'drm-fixes-3.8' of git://people.freedesktop.org/~agd5f/linux into drm...
[karo-tx-linux.git] / net / batman-adv / routing.c
index 376b4cc6ca821ffb4279e2b4df81e61899be038f..1aa1722d01870d69738f6be60a7e7868882cab88 100644 (file)
@@ -28,6 +28,7 @@
 #include "vis.h"
 #include "unicast.h"
 #include "bridge_loop_avoidance.h"
+#include "distributed-arp-table.h"
 
 static int batadv_route_unicast_packet(struct sk_buff *skb,
                                       struct batadv_hard_iface *recv_if);
@@ -284,7 +285,6 @@ static int batadv_recv_my_icmp_packet(struct batadv_priv *bat_priv,
 {
        struct batadv_hard_iface *primary_if = NULL;
        struct batadv_orig_node *orig_node = NULL;
-       struct batadv_neigh_node *router = NULL;
        struct batadv_icmp_packet_rr *icmp_packet;
        int ret = NET_RX_DROP;
 
@@ -306,10 +306,6 @@ static int batadv_recv_my_icmp_packet(struct batadv_priv *bat_priv,
        if (!orig_node)
                goto out;
 
-       router = batadv_orig_node_get_router(orig_node);
-       if (!router)
-               goto out;
-
        /* create a copy of the skb, if needed, to modify it. */
        if (skb_cow(skb, ETH_HLEN) < 0)
                goto out;
@@ -321,14 +317,12 @@ static int batadv_recv_my_icmp_packet(struct batadv_priv *bat_priv,
        icmp_packet->msg_type = BATADV_ECHO_REPLY;
        icmp_packet->header.ttl = BATADV_TTL;
 
-       batadv_send_skb_packet(skb, router->if_incoming, router->addr);
-       ret = NET_RX_SUCCESS;
+       if (batadv_send_skb_to_orig(skb, orig_node, NULL))
+               ret = NET_RX_SUCCESS;
 
 out:
        if (primary_if)
                batadv_hardif_free_ref(primary_if);
-       if (router)
-               batadv_neigh_node_free_ref(router);
        if (orig_node)
                batadv_orig_node_free_ref(orig_node);
        return ret;
@@ -339,7 +333,6 @@ static int batadv_recv_icmp_ttl_exceeded(struct batadv_priv *bat_priv,
 {
        struct batadv_hard_iface *primary_if = NULL;
        struct batadv_orig_node *orig_node = NULL;
-       struct batadv_neigh_node *router = NULL;
        struct batadv_icmp_packet *icmp_packet;
        int ret = NET_RX_DROP;
 
@@ -361,10 +354,6 @@ static int batadv_recv_icmp_ttl_exceeded(struct batadv_priv *bat_priv,
        if (!orig_node)
                goto out;
 
-       router = batadv_orig_node_get_router(orig_node);
-       if (!router)
-               goto out;
-
        /* create a copy of the skb, if needed, to modify it. */
        if (skb_cow(skb, ETH_HLEN) < 0)
                goto out;
@@ -376,14 +365,12 @@ static int batadv_recv_icmp_ttl_exceeded(struct batadv_priv *bat_priv,
        icmp_packet->msg_type = BATADV_TTL_EXCEEDED;
        icmp_packet->header.ttl = BATADV_TTL;
 
-       batadv_send_skb_packet(skb, router->if_incoming, router->addr);
-       ret = NET_RX_SUCCESS;
+       if (batadv_send_skb_to_orig(skb, orig_node, NULL))
+               ret = NET_RX_SUCCESS;
 
 out:
        if (primary_if)
                batadv_hardif_free_ref(primary_if);
-       if (router)
-               batadv_neigh_node_free_ref(router);
        if (orig_node)
                batadv_orig_node_free_ref(orig_node);
        return ret;
@@ -397,7 +384,6 @@ int batadv_recv_icmp_packet(struct sk_buff *skb,
        struct batadv_icmp_packet_rr *icmp_packet;
        struct ethhdr *ethhdr;
        struct batadv_orig_node *orig_node = NULL;
-       struct batadv_neigh_node *router = NULL;
        int hdr_size = sizeof(struct batadv_icmp_packet);
        int ret = NET_RX_DROP;
 
@@ -446,10 +432,6 @@ int batadv_recv_icmp_packet(struct sk_buff *skb,
        if (!orig_node)
                goto out;
 
-       router = batadv_orig_node_get_router(orig_node);
-       if (!router)
-               goto out;
-
        /* create a copy of the skb, if needed, to modify it. */
        if (skb_cow(skb, ETH_HLEN) < 0)
                goto out;
@@ -460,12 +442,10 @@ int batadv_recv_icmp_packet(struct sk_buff *skb,
        icmp_packet->header.ttl--;
 
        /* route it */
-       batadv_send_skb_packet(skb, router->if_incoming, router->addr);
-       ret = NET_RX_SUCCESS;
+       if (batadv_send_skb_to_orig(skb, orig_node, recv_if))
+               ret = NET_RX_SUCCESS;
 
 out:
-       if (router)
-               batadv_neigh_node_free_ref(router);
        if (orig_node)
                batadv_orig_node_free_ref(orig_node);
        return ret;
@@ -549,25 +529,18 @@ batadv_find_ifalter_router(struct batadv_orig_node *primary_orig,
                if (tmp_neigh_node->if_incoming == recv_if)
                        continue;
 
-               if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
+               if (router && tmp_neigh_node->tq_avg <= router->tq_avg)
                        continue;
 
-               /* if we don't have a router yet
-                * or this one is better, choose it.
-                */
-               if ((!router) ||
-                   (tmp_neigh_node->tq_avg > router->tq_avg)) {
-                       /* decrement refcount of
-                        * previously selected router
-                        */
-                       if (router)
-                               batadv_neigh_node_free_ref(router);
+               if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
+                       continue;
 
-                       router = tmp_neigh_node;
-                       atomic_inc_not_zero(&router->refcount);
-               }
+               /* decrement refcount of previously selected router */
+               if (router)
+                       batadv_neigh_node_free_ref(router);
 
-               batadv_neigh_node_free_ref(tmp_neigh_node);
+               /* we found a better router (or at least one valid router) */
+               router = tmp_neigh_node;
        }
 
        /* use the first candidate if nothing was found. */
@@ -687,21 +660,8 @@ int batadv_recv_roam_adv(struct sk_buff *skb, struct batadv_hard_iface *recv_if)
        struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
        struct batadv_roam_adv_packet *roam_adv_packet;
        struct batadv_orig_node *orig_node;
-       struct ethhdr *ethhdr;
-
-       /* drop packet if it has not necessary minimum size */
-       if (unlikely(!pskb_may_pull(skb,
-                                   sizeof(struct batadv_roam_adv_packet))))
-               goto out;
-
-       ethhdr = (struct ethhdr *)skb_mac_header(skb);
-
-       /* packet with unicast indication but broadcast recipient */
-       if (is_broadcast_ether_addr(ethhdr->h_dest))
-               goto out;
 
-       /* packet with broadcast sender address */
-       if (is_broadcast_ether_addr(ethhdr->h_source))
+       if (batadv_check_unicast_packet(skb, sizeof(*roam_adv_packet)) < 0)
                goto out;
 
        batadv_inc_counter(bat_priv, BATADV_CNT_TT_ROAM_ADV_RX);
@@ -730,12 +690,6 @@ int batadv_recv_roam_adv(struct sk_buff *skb, struct batadv_hard_iface *recv_if)
                             BATADV_TT_CLIENT_ROAM,
                             atomic_read(&orig_node->last_ttvn) + 1);
 
-       /* Roaming phase starts: I have new information but the ttvn has not
-        * been incremented yet. This flag will make me check all the incoming
-        * packets for the correct destination.
-        */
-       bat_priv->tt.poss_change = true;
-
        batadv_orig_node_free_ref(orig_node);
 out:
        /* returning NET_RX_DROP will make the caller function kfree the skb */
@@ -907,8 +861,8 @@ static int batadv_route_unicast_packet(struct sk_buff *skb,
                           skb->len + ETH_HLEN);
 
        /* route it */
-       batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
-       ret = NET_RX_SUCCESS;
+       if (batadv_send_skb_to_orig(skb, orig_node, recv_if))
+               ret = NET_RX_SUCCESS;
 
 out:
        if (neigh_node)
@@ -918,80 +872,161 @@ out:
        return ret;
 }
 
+/**
+ * batadv_reroute_unicast_packet - update the unicast header for re-routing
+ * @bat_priv: the bat priv with all the soft interface information
+ * @unicast_packet: the unicast header to be updated
+ * @dst_addr: the payload destination
+ *
+ * Search the translation table for dst_addr and update the unicast header with
+ * the new corresponding information (originator address where the destination
+ * client currently is and its known TTVN)
+ *
+ * Returns true if the packet header has been updated, false otherwise
+ */
+static bool
+batadv_reroute_unicast_packet(struct batadv_priv *bat_priv,
+                             struct batadv_unicast_packet *unicast_packet,
+                             uint8_t *dst_addr)
+{
+       struct batadv_orig_node *orig_node = NULL;
+       struct batadv_hard_iface *primary_if = NULL;
+       bool ret = false;
+       uint8_t *orig_addr, orig_ttvn;
+
+       if (batadv_is_my_client(bat_priv, dst_addr)) {
+               primary_if = batadv_primary_if_get_selected(bat_priv);
+               if (!primary_if)
+                       goto out;
+               orig_addr = primary_if->net_dev->dev_addr;
+               orig_ttvn = (uint8_t)atomic_read(&bat_priv->tt.vn);
+       } else {
+               orig_node = batadv_transtable_search(bat_priv, NULL, dst_addr);
+               if (!orig_node)
+                       goto out;
+
+               if (batadv_compare_eth(orig_node->orig, unicast_packet->dest))
+                       goto out;
+
+               orig_addr = orig_node->orig;
+               orig_ttvn = (uint8_t)atomic_read(&orig_node->last_ttvn);
+       }
+
+       /* update the packet header */
+       memcpy(unicast_packet->dest, orig_addr, ETH_ALEN);
+       unicast_packet->ttvn = orig_ttvn;
+
+       ret = true;
+out:
+       if (primary_if)
+               batadv_hardif_free_ref(primary_if);
+       if (orig_node)
+               batadv_orig_node_free_ref(orig_node);
+
+       return ret;
+}
+
 static int batadv_check_unicast_ttvn(struct batadv_priv *bat_priv,
                                     struct sk_buff *skb) {
-       uint8_t curr_ttvn;
+       uint8_t curr_ttvn, old_ttvn;
        struct batadv_orig_node *orig_node;
        struct ethhdr *ethhdr;
        struct batadv_hard_iface *primary_if;
        struct batadv_unicast_packet *unicast_packet;
-       bool tt_poss_change;
        int is_old_ttvn;
 
-       /* I could need to modify it */
-       if (skb_cow(skb, sizeof(struct batadv_unicast_packet)) < 0)
+       /* check if there is enough data before accessing it */
+       if (pskb_may_pull(skb, sizeof(*unicast_packet) + ETH_HLEN) < 0)
+               return 0;
+
+       /* create a copy of the skb (in case of for re-routing) to modify it. */
+       if (skb_cow(skb, sizeof(*unicast_packet)) < 0)
                return 0;
 
        unicast_packet = (struct batadv_unicast_packet *)skb->data;
+       ethhdr = (struct ethhdr *)(skb->data + sizeof(*unicast_packet));
 
-       if (batadv_is_my_mac(unicast_packet->dest)) {
-               tt_poss_change = bat_priv->tt.poss_change;
-               curr_ttvn = (uint8_t)atomic_read(&bat_priv->tt.vn);
-       } else {
+       /* check if the destination client was served by this node and it is now
+        * roaming. In this case, it means that the node has got a ROAM_ADV
+        * message and that it knows the new destination in the mesh to re-route
+        * the packet to
+        */
+       if (batadv_tt_local_client_is_roaming(bat_priv, ethhdr->h_dest)) {
+               if (batadv_reroute_unicast_packet(bat_priv, unicast_packet,
+                                                 ethhdr->h_dest))
+                       net_ratelimited_function(batadv_dbg, BATADV_DBG_TT,
+                                                bat_priv,
+                                                "Rerouting unicast packet to %pM (dst=%pM): Local Roaming\n",
+                                                unicast_packet->dest,
+                                                ethhdr->h_dest);
+               /* at this point the mesh destination should have been
+                * substituted with the originator address found in the global
+                * table. If not, let the packet go untouched anyway because
+                * there is nothing the node can do
+                */
+               return 1;
+       }
+
+       /* retrieve the TTVN known by this node for the packet destination. This
+        * value is used later to check if the node which sent (or re-routed
+        * last time) the packet had an updated information or not
+        */
+       curr_ttvn = (uint8_t)atomic_read(&bat_priv->tt.vn);
+       if (!batadv_is_my_mac(unicast_packet->dest)) {
                orig_node = batadv_orig_hash_find(bat_priv,
                                                  unicast_packet->dest);
-
+               /* if it is not possible to find the orig_node representing the
+                * destination, the packet can immediately be dropped as it will
+                * not be possible to deliver it
+                */
                if (!orig_node)
                        return 0;
 
                curr_ttvn = (uint8_t)atomic_read(&orig_node->last_ttvn);
-               tt_poss_change = orig_node->tt_poss_change;
                batadv_orig_node_free_ref(orig_node);
        }
 
-       /* Check whether I have to reroute the packet */
+       /* check if the TTVN contained in the packet is fresher than what the
+        * node knows
+        */
        is_old_ttvn = batadv_seq_before(unicast_packet->ttvn, curr_ttvn);
-       if (is_old_ttvn || tt_poss_change) {
-               /* check if there is enough data before accessing it */
-               if (pskb_may_pull(skb, sizeof(struct batadv_unicast_packet) +
-                                 ETH_HLEN) < 0)
-                       return 0;
+       if (!is_old_ttvn)
+               return 1;
 
-               ethhdr = (struct ethhdr *)(skb->data + sizeof(*unicast_packet));
+       old_ttvn = unicast_packet->ttvn;
+       /* the packet was forged based on outdated network information. Its
+        * destination can possibly be updated and forwarded towards the new
+        * target host
+        */
+       if (batadv_reroute_unicast_packet(bat_priv, unicast_packet,
+                                         ethhdr->h_dest)) {
+               net_ratelimited_function(batadv_dbg, BATADV_DBG_TT, bat_priv,
+                                        "Rerouting unicast packet to %pM (dst=%pM): TTVN mismatch old_ttvn=%u new_ttvn=%u\n",
+                                        unicast_packet->dest, ethhdr->h_dest,
+                                        old_ttvn, curr_ttvn);
+               return 1;
+       }
 
-               /* we don't have an updated route for this client, so we should
-                * not try to reroute the packet!!
-                */
-               if (batadv_tt_global_client_is_roaming(bat_priv,
-                                                      ethhdr->h_dest))
-                       return 1;
+       /* the packet has not been re-routed: either the destination is
+        * currently served by this node or there is no destination at all and
+        * it is possible to drop the packet
+        */
+       if (!batadv_is_my_client(bat_priv, ethhdr->h_dest))
+               return 0;
 
-               orig_node = batadv_transtable_search(bat_priv, NULL,
-                                                    ethhdr->h_dest);
-
-               if (!orig_node) {
-                       if (!batadv_is_my_client(bat_priv, ethhdr->h_dest))
-                               return 0;
-                       primary_if = batadv_primary_if_get_selected(bat_priv);
-                       if (!primary_if)
-                               return 0;
-                       memcpy(unicast_packet->dest,
-                              primary_if->net_dev->dev_addr, ETH_ALEN);
-                       batadv_hardif_free_ref(primary_if);
-               } else {
-                       memcpy(unicast_packet->dest, orig_node->orig,
-                              ETH_ALEN);
-                       curr_ttvn = (uint8_t)atomic_read(&orig_node->last_ttvn);
-                       batadv_orig_node_free_ref(orig_node);
-               }
+       /* update the header in order to let the packet be delivered to this
+        * node's soft interface
+        */
+       primary_if = batadv_primary_if_get_selected(bat_priv);
+       if (!primary_if)
+               return 0;
 
-               batadv_dbg(BATADV_DBG_ROUTES, bat_priv,
-                          "TTVN mismatch (old_ttvn %u new_ttvn %u)! Rerouting unicast packet (for %pM) to %pM\n",
-                          unicast_packet->ttvn, curr_ttvn, ethhdr->h_dest,
-                          unicast_packet->dest);
+       memcpy(unicast_packet->dest, primary_if->net_dev->dev_addr, ETH_ALEN);
+
+       batadv_hardif_free_ref(primary_if);
+
+       unicast_packet->ttvn = curr_ttvn;
 
-               unicast_packet->ttvn = curr_ttvn;
-       }
        return 1;
 }
 
@@ -1000,7 +1035,19 @@ int batadv_recv_unicast_packet(struct sk_buff *skb,
 {
        struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
        struct batadv_unicast_packet *unicast_packet;
+       struct batadv_unicast_4addr_packet *unicast_4addr_packet;
+       uint8_t *orig_addr;
+       struct batadv_orig_node *orig_node = NULL;
        int hdr_size = sizeof(*unicast_packet);
+       bool is4addr;
+
+       unicast_packet = (struct batadv_unicast_packet *)skb->data;
+       unicast_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data;
+
+       is4addr = unicast_packet->header.packet_type == BATADV_UNICAST_4ADDR;
+       /* the caller function should have already pulled 2 bytes */
+       if (is4addr)
+               hdr_size = sizeof(*unicast_4addr_packet);
 
        if (batadv_check_unicast_packet(skb, hdr_size) < 0)
                return NET_RX_DROP;
@@ -1008,12 +1055,28 @@ int batadv_recv_unicast_packet(struct sk_buff *skb,
        if (!batadv_check_unicast_ttvn(bat_priv, skb))
                return NET_RX_DROP;
 
-       unicast_packet = (struct batadv_unicast_packet *)skb->data;
-
        /* packet for me */
        if (batadv_is_my_mac(unicast_packet->dest)) {
+               if (is4addr) {
+                       batadv_dat_inc_counter(bat_priv,
+                                              unicast_4addr_packet->subtype);
+                       orig_addr = unicast_4addr_packet->src;
+                       orig_node = batadv_orig_hash_find(bat_priv, orig_addr);
+               }
+
+               if (batadv_dat_snoop_incoming_arp_request(bat_priv, skb,
+                                                         hdr_size))
+                       goto rx_success;
+               if (batadv_dat_snoop_incoming_arp_reply(bat_priv, skb,
+                                                       hdr_size))
+                       goto rx_success;
+
                batadv_interface_rx(recv_if->soft_iface, skb, recv_if, hdr_size,
-                                   NULL);
+                                   orig_node);
+
+rx_success:
+               if (orig_node)
+                       batadv_orig_node_free_ref(orig_node);
 
                return NET_RX_SUCCESS;
        }
@@ -1050,8 +1113,17 @@ int batadv_recv_ucast_frag_packet(struct sk_buff *skb,
                if (!new_skb)
                        return NET_RX_SUCCESS;
 
+               if (batadv_dat_snoop_incoming_arp_request(bat_priv, new_skb,
+                                                         hdr_size))
+                       goto rx_success;
+               if (batadv_dat_snoop_incoming_arp_reply(bat_priv, new_skb,
+                                                       hdr_size))
+                       goto rx_success;
+
                batadv_interface_rx(recv_if->soft_iface, new_skb, recv_if,
                                    sizeof(struct batadv_unicast_packet), NULL);
+
+rx_success:
                return NET_RX_SUCCESS;
        }
 
@@ -1124,14 +1196,8 @@ int batadv_recv_bcast_packet(struct sk_buff *skb,
 
        spin_unlock_bh(&orig_node->bcast_seqno_lock);
 
-       /* keep skb linear for crc calculation */
-       if (skb_linearize(skb) < 0)
-               goto out;
-
-       bcast_packet = (struct batadv_bcast_packet *)skb->data;
-
        /* check whether this has been sent by another originator before */
-       if (batadv_bla_check_bcast_duplist(bat_priv, bcast_packet, skb->len))
+       if (batadv_bla_check_bcast_duplist(bat_priv, skb))
                goto out;
 
        /* rebroadcast packet */
@@ -1143,9 +1209,16 @@ int batadv_recv_bcast_packet(struct sk_buff *skb,
        if (batadv_bla_is_backbone_gw(skb, orig_node, hdr_size))
                goto out;
 
+       if (batadv_dat_snoop_incoming_arp_request(bat_priv, skb, hdr_size))
+               goto rx_success;
+       if (batadv_dat_snoop_incoming_arp_reply(bat_priv, skb, hdr_size))
+               goto rx_success;
+
        /* broadcast for me */
        batadv_interface_rx(recv_if->soft_iface, skb, recv_if, hdr_size,
                            orig_node);
+
+rx_success:
        ret = NET_RX_SUCCESS;
        goto out;