batman-adv: agglomerate all batman iv ogm processing functions in a single file

In preparation of the upcoming improved routing algorithm the code based has
to be re-organized to allow choosing the routing algorithm at compile time.

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>

1 files changed, 639 insertions, 0 deletions

diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c
new file mode 100644
index 000000000000..6fa2d465b6cd
--- /dev/null
+++ b/net/batman-adv/bat_iv_ogm.c
@@ -0,0 +1,639 @@
+/*
+ * Copyright (C) 2007-2011 B.A.T.M.A.N. contributors:
+ *
+ * Marek Lindner, Simon Wunderlich
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA
+ *
+ */
+
+#include "main.h"
+#include "bat_ogm.h"
+#include "translation-table.h"
+#include "ring_buffer.h"
+#include "originator.h"
+#include "routing.h"
+#include "gateway_common.h"
+#include "gateway_client.h"
+#include "hard-interface.h"
+#include "send.h"
+
+/* is there another aggregated packet here? */
+static int bat_ogm_aggr_packet(int buff_pos, int packet_len,
+                               int tt_num_changes)
+{
+        int next_buff_pos = buff_pos + BATMAN_OGM_LEN + tt_len(tt_num_changes);
+
+        return (next_buff_pos <= packet_len) &&
+                (next_buff_pos <= MAX_AGGREGATION_BYTES);
+}
+
+static void bat_ogm_orig_update(struct bat_priv *bat_priv,
+                                struct orig_node *orig_node,
+                                const struct ethhdr *ethhdr,
+                                const struct batman_ogm_packet
+                                                        *batman_ogm_packet,
+                                struct hard_iface *if_incoming,
+                                const unsigned char *tt_buff, int is_duplicate)
+{
+        struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
+        struct neigh_node *router = NULL;
+        struct orig_node *orig_node_tmp;
+        struct hlist_node *node;
+        uint8_t bcast_own_sum_orig, bcast_own_sum_neigh;
+
+        bat_dbg(DBG_BATMAN, bat_priv, "update_originator(): "
+                "Searching and updating originator entry of received packet\n");
+
+        rcu_read_lock();
+        hlist_for_each_entry_rcu(tmp_neigh_node, node,
+                                 &orig_node->neigh_list, list) {
+                if (compare_eth(tmp_neigh_node->addr, ethhdr->h_source) &&
+                    (tmp_neigh_node->if_incoming == if_incoming) &&
+                     atomic_inc_not_zero(&tmp_neigh_node->refcount)) {
+                        if (neigh_node)
+                                neigh_node_free_ref(neigh_node);
+                        neigh_node = tmp_neigh_node;
+                        continue;
+                }
+
+                if (is_duplicate)
+                        continue;
+
+                spin_lock_bh(&tmp_neigh_node->tq_lock);
+                ring_buffer_set(tmp_neigh_node->tq_recv,
+                                &tmp_neigh_node->tq_index, 0);
+                tmp_neigh_node->tq_avg =
+                        ring_buffer_avg(tmp_neigh_node->tq_recv);
+                spin_unlock_bh(&tmp_neigh_node->tq_lock);
+        }
+
+        if (!neigh_node) {
+                struct orig_node *orig_tmp;
+
+                orig_tmp = get_orig_node(bat_priv, ethhdr->h_source);
+                if (!orig_tmp)
+                        goto unlock;
+
+                neigh_node = create_neighbor(orig_node, orig_tmp,
+                                             ethhdr->h_source, if_incoming);
+
+                orig_node_free_ref(orig_tmp);
+                if (!neigh_node)
+                        goto unlock;
+        } else
+                bat_dbg(DBG_BATMAN, bat_priv,
+                        "Updating existing last-hop neighbor of originator\n");
+
+        rcu_read_unlock();
+
+        orig_node->flags = batman_ogm_packet->flags;
+        neigh_node->last_valid = jiffies;
+
+        spin_lock_bh(&neigh_node->tq_lock);
+        ring_buffer_set(neigh_node->tq_recv,
+                        &neigh_node->tq_index,
+                        batman_ogm_packet->tq);
+        neigh_node->tq_avg = ring_buffer_avg(neigh_node->tq_recv);
+        spin_unlock_bh(&neigh_node->tq_lock);
+
+        if (!is_duplicate) {
+                orig_node->last_ttl = batman_ogm_packet->ttl;
+                neigh_node->last_ttl = batman_ogm_packet->ttl;
+        }
+
+        bonding_candidate_add(orig_node, neigh_node);
+
+        /* if this neighbor already is our next hop there is nothing
+         * to change */
+        router = orig_node_get_router(orig_node);
+        if (router == neigh_node)
+                goto update_tt;
+
+        /* if this neighbor does not offer a better TQ we won't consider it */
+        if (router && (router->tq_avg > neigh_node->tq_avg))
+                goto update_tt;
+
+        /* if the TQ is the same and the link not more symmetric we
+         * won't consider it either */
+        if (router && (neigh_node->tq_avg == router->tq_avg)) {
+                orig_node_tmp = router->orig_node;
+                spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
+                bcast_own_sum_orig =
+                        orig_node_tmp->bcast_own_sum[if_incoming->if_num];
+                spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
+
+                orig_node_tmp = neigh_node->orig_node;
+                spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
+                bcast_own_sum_neigh =
+                        orig_node_tmp->bcast_own_sum[if_incoming->if_num];
+                spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
+
+                if (bcast_own_sum_orig >= bcast_own_sum_neigh)
+                        goto update_tt;
+        }
+
+        update_route(bat_priv, orig_node, neigh_node);
+
+update_tt:
+        /* I have to check for transtable changes only if the OGM has been
+         * sent through a primary interface */
+        if (((batman_ogm_packet->orig != ethhdr->h_source) &&
+             (batman_ogm_packet->ttl > 2)) ||
+            (batman_ogm_packet->flags & PRIMARIES_FIRST_HOP))
+                tt_update_orig(bat_priv, orig_node, tt_buff,
+                               batman_ogm_packet->tt_num_changes,
+                               batman_ogm_packet->ttvn,
+                               batman_ogm_packet->tt_crc);
+
+        if (orig_node->gw_flags != batman_ogm_packet->gw_flags)
+                gw_node_update(bat_priv, orig_node,
+                               batman_ogm_packet->gw_flags);
+
+        orig_node->gw_flags = batman_ogm_packet->gw_flags;
+
+        /* restart gateway selection if fast or late switching was enabled */
+        if ((orig_node->gw_flags) &&
+            (atomic_read(&bat_priv->gw_mode) == GW_MODE_CLIENT) &&
+            (atomic_read(&bat_priv->gw_sel_class) > 2))
+                gw_check_election(bat_priv, orig_node);
+
+        goto out;
+
+unlock:
+        rcu_read_unlock();
+out:
+        if (neigh_node)
+                neigh_node_free_ref(neigh_node);
+        if (router)
+                neigh_node_free_ref(router);
+}
+
+static int bat_ogm_calc_tq(struct orig_node *orig_node,
+                           struct orig_node *orig_neigh_node,
+                           struct batman_ogm_packet *batman_ogm_packet,
+                           struct hard_iface *if_incoming)
+{
+        struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
+        struct neigh_node *neigh_node = NULL, *tmp_neigh_node;
+        struct hlist_node *node;
+        uint8_t total_count;
+        uint8_t orig_eq_count, neigh_rq_count, tq_own;
+        int tq_asym_penalty, ret = 0;
+
+        /* find corresponding one hop neighbor */
+        rcu_read_lock();
+        hlist_for_each_entry_rcu(tmp_neigh_node, node,
+                                 &orig_neigh_node->neigh_list, list) {
+
+                if (!compare_eth(tmp_neigh_node->addr, orig_neigh_node->orig))
+                        continue;
+
+                if (tmp_neigh_node->if_incoming != if_incoming)
+                        continue;
+
+                if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
+                        continue;
+
+                neigh_node = tmp_neigh_node;
+                break;
+        }
+        rcu_read_unlock();
+
+        if (!neigh_node)
+                neigh_node = create_neighbor(orig_neigh_node,
+                                             orig_neigh_node,
+                                             orig_neigh_node->orig,
+                                             if_incoming);
+
+        if (!neigh_node)
+                goto out;
+
+        /* if orig_node is direct neighbor update neigh_node last_valid */
+        if (orig_node == orig_neigh_node)
+                neigh_node->last_valid = jiffies;
+
+        orig_node->last_valid = jiffies;
+
+        /* find packet count of corresponding one hop neighbor */
+        spin_lock_bh(&orig_node->ogm_cnt_lock);
+        orig_eq_count = orig_neigh_node->bcast_own_sum[if_incoming->if_num];
+        neigh_rq_count = neigh_node->real_packet_count;
+        spin_unlock_bh(&orig_node->ogm_cnt_lock);
+
+        /* pay attention to not get a value bigger than 100 % */
+        total_count = (orig_eq_count > neigh_rq_count ?
+                       neigh_rq_count : orig_eq_count);
+
+        /* if we have too few packets (too less data) we set tq_own to zero */
+        /* if we receive too few packets it is not considered bidirectional */
+        if ((total_count < TQ_LOCAL_BIDRECT_SEND_MINIMUM) ||
+            (neigh_rq_count < TQ_LOCAL_BIDRECT_RECV_MINIMUM))
+                tq_own = 0;
+        else
+                /* neigh_node->real_packet_count is never zero as we
+                 * only purge old information when getting new
+                 * information */
+                tq_own = (TQ_MAX_VALUE * total_count) / neigh_rq_count;
+
+        /*
+         * 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
+         * affect the nearly-symmetric links only a little, but
+         * punishes asymmetric links more.  This will give a value
+         * between 0 and TQ_MAX_VALUE
+         */
+        tq_asym_penalty = TQ_MAX_VALUE - (TQ_MAX_VALUE *
+                                (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count) *
+                                (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count) *
+                                (TQ_LOCAL_WINDOW_SIZE - neigh_rq_count)) /
+                                        (TQ_LOCAL_WINDOW_SIZE *
+                                         TQ_LOCAL_WINDOW_SIZE *
+                                         TQ_LOCAL_WINDOW_SIZE);
+
+        batman_ogm_packet->tq = ((batman_ogm_packet->tq * tq_own
+                                                        * tq_asym_penalty) /
+                                                (TQ_MAX_VALUE * TQ_MAX_VALUE));
+
+        bat_dbg(DBG_BATMAN, bat_priv,
+                "bidirectional: "
+                "orig = %-15pM neigh = %-15pM => own_bcast = %2i, "
+                "real recv = %2i, local tq: %3i, asym_penalty: %3i, "
+                "total tq: %3i\n",
+                orig_node->orig, orig_neigh_node->orig, total_count,
+                neigh_rq_count, tq_own, tq_asym_penalty, batman_ogm_packet->tq);
+
+        /* if link has the minimum required transmission quality
+         * consider it bidirectional */
+        if (batman_ogm_packet->tq >= TQ_TOTAL_BIDRECT_LIMIT)
+                ret = 1;
+
+out:
+        if (neigh_node)
+                neigh_node_free_ref(neigh_node);
+        return ret;
+}
+
+/* processes a batman packet for all interfaces, adjusts the sequence number and
+ * finds out whether it is a duplicate.
+ * returns:
+ *   1 the packet is a duplicate
+ *   0 the packet has not yet been received
+ *  -1 the packet is old and has been received while the seqno window
+ *     was protected. Caller should drop it.
+ */
+static int bat_ogm_update_seqnos(const struct ethhdr *ethhdr,
+                                 const struct batman_ogm_packet
+                                                        *batman_ogm_packet,
+                                 const struct hard_iface *if_incoming)
+{
+        struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
+        struct orig_node *orig_node;
+        struct neigh_node *tmp_neigh_node;
+        struct hlist_node *node;
+        int is_duplicate = 0;
+        int32_t seq_diff;
+        int need_update = 0;
+        int set_mark, ret = -1;
+
+        orig_node = get_orig_node(bat_priv, batman_ogm_packet->orig);
+        if (!orig_node)
+                return 0;
+
+        spin_lock_bh(&orig_node->ogm_cnt_lock);
+        seq_diff = batman_ogm_packet->seqno - orig_node->last_real_seqno;
+
+        /* signalize caller that the packet is to be dropped. */
+        if (window_protected(bat_priv, seq_diff,
+                             &orig_node->batman_seqno_reset))
+                goto out;
+
+        rcu_read_lock();
+        hlist_for_each_entry_rcu(tmp_neigh_node, node,
+                                 &orig_node->neigh_list, list) {
+
+                is_duplicate |= get_bit_status(tmp_neigh_node->real_bits,
+                                               orig_node->last_real_seqno,
+                                               batman_ogm_packet->seqno);
+
+                if (compare_eth(tmp_neigh_node->addr, ethhdr->h_source) &&
+                    (tmp_neigh_node->if_incoming == if_incoming))
+                        set_mark = 1;
+                else
+                        set_mark = 0;
+
+                /* if the window moved, set the update flag. */
+                need_update |= bit_get_packet(bat_priv,
+                                              tmp_neigh_node->real_bits,
+                                              seq_diff, set_mark);
+
+                tmp_neigh_node->real_packet_count =
+                        bit_packet_count(tmp_neigh_node->real_bits);
+        }
+        rcu_read_unlock();
+
+        if (need_update) {
+                bat_dbg(DBG_BATMAN, bat_priv,
+                        "updating last_seqno: old %d, new %d\n",
+                        orig_node->last_real_seqno, batman_ogm_packet->seqno);
+                orig_node->last_real_seqno = batman_ogm_packet->seqno;
+        }
+
+        ret = is_duplicate;
+
+out:
+        spin_unlock_bh(&orig_node->ogm_cnt_lock);
+        orig_node_free_ref(orig_node);
+        return ret;
+}
+
+static void bat_ogm_process(const struct ethhdr *ethhdr,
+                            struct batman_ogm_packet *batman_ogm_packet,
+                            const unsigned char *tt_buff,
+                            struct hard_iface *if_incoming)
+{
+        struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
+        struct hard_iface *hard_iface;
+        struct orig_node *orig_neigh_node, *orig_node;
+        struct neigh_node *router = NULL, *router_router = NULL;
+        struct neigh_node *orig_neigh_router = NULL;
+        int has_directlink_flag;
+        int is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0;
+        int is_broadcast = 0, is_bidirectional, is_single_hop_neigh;
+        int is_duplicate;
+        uint32_t if_incoming_seqno;
+
+        /* Silently drop when the batman packet is actually not a
+         * correct packet.
+         *
+         * This might happen if a packet is padded (e.g. Ethernet has a
+         * minimum frame length of 64 byte) and the aggregation interprets
+         * it as an additional length.
+         *
+         * TODO: A more sane solution would be to have a bit in the
+         * batman_ogm_packet to detect whether the packet is the last
+         * packet in an aggregation.  Here we expect that the padding
+         * is always zero (or not 0x01)
+         */
+        if (batman_ogm_packet->packet_type != BAT_OGM)
+                return;
+
+        /* could be changed by schedule_own_packet() */
+        if_incoming_seqno = atomic_read(&if_incoming->seqno);
+
+        has_directlink_flag = (batman_ogm_packet->flags & DIRECTLINK ? 1 : 0);
+
+        is_single_hop_neigh = (compare_eth(ethhdr->h_source,
+                                           batman_ogm_packet->orig) ? 1 : 0);
+
+        bat_dbg(DBG_BATMAN, bat_priv,
+                "Received BATMAN packet via NB: %pM, IF: %s [%pM] "
+                "(from OG: %pM, via prev OG: %pM, seqno %d, ttvn %u, "
+                "crc %u, changes %u, td %d, TTL %d, V %d, IDF %d)\n",
+                ethhdr->h_source, if_incoming->net_dev->name,
+                if_incoming->net_dev->dev_addr, batman_ogm_packet->orig,
+                batman_ogm_packet->prev_sender, batman_ogm_packet->seqno,
+                batman_ogm_packet->ttvn, batman_ogm_packet->tt_crc,
+                batman_ogm_packet->tt_num_changes, batman_ogm_packet->tq,
+                batman_ogm_packet->ttl, batman_ogm_packet->version,
+                has_directlink_flag);
+
+        rcu_read_lock();
+        list_for_each_entry_rcu(hard_iface, &hardif_list, list) {
+                if (hard_iface->if_status != IF_ACTIVE)
+                        continue;
+
+                if (hard_iface->soft_iface != if_incoming->soft_iface)
+                        continue;
+
+                if (compare_eth(ethhdr->h_source,
+                                hard_iface->net_dev->dev_addr))
+                        is_my_addr = 1;
+
+                if (compare_eth(batman_ogm_packet->orig,
+                                hard_iface->net_dev->dev_addr))
+                        is_my_orig = 1;
+
+                if (compare_eth(batman_ogm_packet->prev_sender,
+                                hard_iface->net_dev->dev_addr))
+                        is_my_oldorig = 1;
+
+                if (is_broadcast_ether_addr(ethhdr->h_source))
+                        is_broadcast = 1;
+        }
+        rcu_read_unlock();
+
+        if (batman_ogm_packet->version != COMPAT_VERSION) {
+                bat_dbg(DBG_BATMAN, bat_priv,
+                        "Drop packet: incompatible batman version (%i)\n",
+                        batman_ogm_packet->version);
+                return;
+        }
+
+        if (is_my_addr) {
+                bat_dbg(DBG_BATMAN, bat_priv,
+                        "Drop packet: received my own broadcast (sender: %pM"
+                        ")\n",
+                        ethhdr->h_source);
+                return;
+        }
+
+        if (is_broadcast) {
+                bat_dbg(DBG_BATMAN, bat_priv, "Drop packet: "
+                "ignoring all packets with broadcast source addr (sender: %pM"
+                ")\n", ethhdr->h_source);
+                return;
+        }
+
+        if (is_my_orig) {
+                unsigned long *word;
+                int offset;
+
+                orig_neigh_node = get_orig_node(bat_priv, ethhdr->h_source);
+                if (!orig_neigh_node)
+                        return;
+
+                /* neighbor has to indicate direct link and it has to
+                 * come via the corresponding interface */
+                /* save packet seqno for bidirectional check */
+                if (has_directlink_flag &&
+                    compare_eth(if_incoming->net_dev->dev_addr,
+                                batman_ogm_packet->orig)) {
+                        offset = if_incoming->if_num * NUM_WORDS;
+
+                        spin_lock_bh(&orig_neigh_node->ogm_cnt_lock);
+                        word = &(orig_neigh_node->bcast_own[offset]);
+                        bit_mark(word,
+                                 if_incoming_seqno -
+                                                batman_ogm_packet->seqno - 2);
+                        orig_neigh_node->bcast_own_sum[if_incoming->if_num] =
+                                bit_packet_count(word);
+                        spin_unlock_bh(&orig_neigh_node->ogm_cnt_lock);
+                }
+
+                bat_dbg(DBG_BATMAN, bat_priv, "Drop packet: "
+                        "originator packet from myself (via neighbor)\n");
+                orig_node_free_ref(orig_neigh_node);
+                return;
+        }
+
+        if (is_my_oldorig) {
+                bat_dbg(DBG_BATMAN, bat_priv,
+                        "Drop packet: ignoring all rebroadcast echos (sender: "
+                        "%pM)\n", ethhdr->h_source);
+                return;
+        }
+
+        orig_node = get_orig_node(bat_priv, batman_ogm_packet->orig);
+        if (!orig_node)
+                return;
+
+        is_duplicate = bat_ogm_update_seqnos(ethhdr, batman_ogm_packet,
+                                             if_incoming);
+
+        if (is_duplicate == -1) {
+                bat_dbg(DBG_BATMAN, bat_priv,
+                        "Drop packet: packet within seqno protection time "
+                        "(sender: %pM)\n", ethhdr->h_source);
+                goto out;
+        }
+
+        if (batman_ogm_packet->tq == 0) {
+                bat_dbg(DBG_BATMAN, bat_priv,
+                        "Drop packet: originator packet with tq equal 0\n");
+                goto out;
+        }
+
+        router = orig_node_get_router(orig_node);
+        if (router)
+                router_router = orig_node_get_router(router->orig_node);
+
+        /* avoid temporary routing loops */
+        if (router && router_router &&
+            (compare_eth(router->addr, batman_ogm_packet->prev_sender)) &&
+            !(compare_eth(batman_ogm_packet->orig,
+                          batman_ogm_packet->prev_sender)) &&
+            (compare_eth(router->addr, router_router->addr))) {
+                bat_dbg(DBG_BATMAN, bat_priv,
+                        "Drop packet: ignoring all rebroadcast packets that "
+                        "may make me loop (sender: %pM)\n", ethhdr->h_source);
+                goto out;
+        }
+
+        /* if sender is a direct neighbor the sender mac equals
+         * originator mac */
+        orig_neigh_node = (is_single_hop_neigh ?
+                           orig_node :
+                           get_orig_node(bat_priv, ethhdr->h_source));
+        if (!orig_neigh_node)
+                goto out;
+
+        orig_neigh_router = orig_node_get_router(orig_neigh_node);
+
+        /* drop packet if sender is not a direct neighbor and if we
+         * don't route towards it */
+        if (!is_single_hop_neigh && (!orig_neigh_router)) {
+                bat_dbg(DBG_BATMAN, bat_priv,
+                        "Drop packet: OGM via unknown neighbor!\n");
+                goto out_neigh;
+        }
+
+        is_bidirectional = bat_ogm_calc_tq(orig_node, orig_neigh_node,
+                                           batman_ogm_packet, if_incoming);
+
+        bonding_save_primary(orig_node, orig_neigh_node, batman_ogm_packet);
+
+        /* update ranking if it is not a duplicate or has the same
+         * seqno and similar ttl as the non-duplicate */
+        if (is_bidirectional &&
+            (!is_duplicate ||
+             ((orig_node->last_real_seqno == batman_ogm_packet->seqno) &&
+              (orig_node->last_ttl - 3 <= batman_ogm_packet->ttl))))
+                bat_ogm_orig_update(bat_priv, orig_node, ethhdr,
+                                    batman_ogm_packet, if_incoming,
+                                    tt_buff, is_duplicate);
+
+        /* is single hop (direct) neighbor */
+        if (is_single_hop_neigh) {
+
+                /* mark direct link on incoming interface */
+                schedule_forward_packet(orig_node, ethhdr, batman_ogm_packet,
+                                        1, if_incoming);
+
+                bat_dbg(DBG_BATMAN, bat_priv, "Forwarding packet: "
+                        "rebroadcast neighbor packet with direct link flag\n");
+                goto out_neigh;
+        }
+
+        /* multihop originator */
+        if (!is_bidirectional) {
+                bat_dbg(DBG_BATMAN, bat_priv,
+                        "Drop packet: not received via bidirectional link\n");
+                goto out_neigh;
+        }
+
+        if (is_duplicate) {
+                bat_dbg(DBG_BATMAN, bat_priv,
+                        "Drop packet: duplicate packet received\n");
+                goto out_neigh;
+        }
+
+        bat_dbg(DBG_BATMAN, bat_priv,
+                "Forwarding packet: rebroadcast originator packet\n");
+        schedule_forward_packet(orig_node, ethhdr, batman_ogm_packet,
+                                0, if_incoming);
+
+out_neigh:
+        if ((orig_neigh_node) && (!is_single_hop_neigh))
+                orig_node_free_ref(orig_neigh_node);
+out:
+        if (router)
+                neigh_node_free_ref(router);
+        if (router_router)
+                neigh_node_free_ref(router_router);
+        if (orig_neigh_router)
+                neigh_node_free_ref(orig_neigh_router);
+
+        orig_node_free_ref(orig_node);
+}
+
+void bat_ogm_receive(const struct ethhdr *ethhdr, unsigned char *packet_buff,
+                     int packet_len, struct hard_iface *if_incoming)
+{
+        struct batman_ogm_packet *batman_ogm_packet;
+        int buff_pos = 0;
+        unsigned char *tt_buff;
+
+        batman_ogm_packet = (struct batman_ogm_packet *)packet_buff;
+
+        /* unpack the aggregated packets and process them one by one */
+        do {
+                /* network to host order for our 32bit seqno and the
+                   orig_interval */
+                batman_ogm_packet->seqno = ntohl(batman_ogm_packet->seqno);
+                batman_ogm_packet->tt_crc = ntohs(batman_ogm_packet->tt_crc);
+
+                tt_buff = packet_buff + buff_pos + BATMAN_OGM_LEN;
+
+                bat_ogm_process(ethhdr, batman_ogm_packet,
+                                tt_buff, if_incoming);
+
+                buff_pos += BATMAN_OGM_LEN +
+                                tt_len(batman_ogm_packet->tt_num_changes);
+
+                batman_ogm_packet = (struct batman_ogm_packet *)
+                                                (packet_buff + buff_pos);
+        } while (bat_ogm_aggr_packet(buff_pos, packet_len,
+                                     batman_ogm_packet->tt_num_changes));
+}