net: Add batman-adv meshing protocol
B.A.T.M.A.N. (better approach to mobile ad-hoc networking) is a routing
protocol for multi-hop ad-hoc mesh networks. The networks may be wired or
wireless. See http://www.open-mesh.org/ for more information and user space
tools.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/batman-adv/vis.c b/net/batman-adv/vis.c
new file mode 100644
index 0000000..cd4c423
--- /dev/null
+++ b/net/batman-adv/vis.c
@@ -0,0 +1,949 @@
+/*
+ * Copyright (C) 2008-2010 B.A.T.M.A.N. contributors:
+ *
+ * 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 "send.h"
+#include "translation-table.h"
+#include "vis.h"
+#include "soft-interface.h"
+#include "hard-interface.h"
+#include "hash.h"
+#include "originator.h"
+
+#define MAX_VIS_PACKET_SIZE 1000
+
+/* Returns the smallest signed integer in two's complement with the sizeof x */
+#define smallest_signed_int(x) (1u << (7u + 8u * (sizeof(x) - 1u)))
+
+/* Checks if a sequence number x is a predecessor/successor of y.
+ * they handle overflows/underflows and can correctly check for a
+ * predecessor/successor unless the variable sequence number has grown by
+ * more then 2**(bitwidth(x)-1)-1.
+ * This means that for a uint8_t with the maximum value 255, it would think:
+ * - when adding nothing - it is neither a predecessor nor a successor
+ * - before adding more than 127 to the starting value - it is a predecessor,
+ * - when adding 128 - it is neither a predecessor nor a successor,
+ * - after adding more than 127 to the starting value - it is a successor */
+#define seq_before(x, y) ({typeof(x) _dummy = (x - y); \
+ _dummy > smallest_signed_int(_dummy); })
+#define seq_after(x, y) seq_before(y, x)
+
+static void start_vis_timer(struct bat_priv *bat_priv);
+
+/* free the info */
+static void free_info(struct kref *ref)
+{
+ struct vis_info *info = container_of(ref, struct vis_info, refcount);
+ struct bat_priv *bat_priv = info->bat_priv;
+ struct recvlist_node *entry, *tmp;
+
+ list_del_init(&info->send_list);
+ spin_lock_bh(&bat_priv->vis_list_lock);
+ list_for_each_entry_safe(entry, tmp, &info->recv_list, list) {
+ list_del(&entry->list);
+ kfree(entry);
+ }
+
+ spin_unlock_bh(&bat_priv->vis_list_lock);
+ kfree_skb(info->skb_packet);
+}
+
+/* Compare two vis packets, used by the hashing algorithm */
+static int vis_info_cmp(void *data1, void *data2)
+{
+ struct vis_info *d1, *d2;
+ struct vis_packet *p1, *p2;
+ d1 = data1;
+ d2 = data2;
+ p1 = (struct vis_packet *)d1->skb_packet->data;
+ p2 = (struct vis_packet *)d2->skb_packet->data;
+ return compare_orig(p1->vis_orig, p2->vis_orig);
+}
+
+/* hash function to choose an entry in a hash table of given size */
+/* hash algorithm from http://en.wikipedia.org/wiki/Hash_table */
+static int vis_info_choose(void *data, int size)
+{
+ struct vis_info *vis_info = data;
+ struct vis_packet *packet;
+ unsigned char *key;
+ uint32_t hash = 0;
+ size_t i;
+
+ packet = (struct vis_packet *)vis_info->skb_packet->data;
+ key = packet->vis_orig;
+ for (i = 0; i < ETH_ALEN; i++) {
+ hash += key[i];
+ hash += (hash << 10);
+ hash ^= (hash >> 6);
+ }
+
+ hash += (hash << 3);
+ hash ^= (hash >> 11);
+ hash += (hash << 15);
+
+ return hash % size;
+}
+
+/* insert interface to the list of interfaces of one originator, if it
+ * does not already exist in the list */
+static void vis_data_insert_interface(const uint8_t *interface,
+ struct hlist_head *if_list,
+ bool primary)
+{
+ struct if_list_entry *entry;
+ struct hlist_node *pos;
+
+ hlist_for_each_entry(entry, pos, if_list, list) {
+ if (compare_orig(entry->addr, (void *)interface))
+ return;
+ }
+
+ /* its a new address, add it to the list */
+ entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
+ if (!entry)
+ return;
+ memcpy(entry->addr, interface, ETH_ALEN);
+ entry->primary = primary;
+ hlist_add_head(&entry->list, if_list);
+}
+
+static ssize_t vis_data_read_prim_sec(char *buff, struct hlist_head *if_list)
+{
+ struct if_list_entry *entry;
+ struct hlist_node *pos;
+ size_t len = 0;
+
+ hlist_for_each_entry(entry, pos, if_list, list) {
+ if (entry->primary)
+ len += sprintf(buff + len, "PRIMARY, ");
+ else
+ len += sprintf(buff + len, "SEC %pM, ", entry->addr);
+ }
+
+ return len;
+}
+
+static size_t vis_data_count_prim_sec(struct hlist_head *if_list)
+{
+ struct if_list_entry *entry;
+ struct hlist_node *pos;
+ size_t count = 0;
+
+ hlist_for_each_entry(entry, pos, if_list, list) {
+ if (entry->primary)
+ count += 9;
+ else
+ count += 23;
+ }
+
+ return count;
+}
+
+/* read an entry */
+static ssize_t vis_data_read_entry(char *buff, struct vis_info_entry *entry,
+ uint8_t *src, bool primary)
+{
+ /* maximal length: max(4+17+2, 3+17+1+3+2) == 26 */
+ if (primary && entry->quality == 0)
+ return sprintf(buff, "HNA %pM, ", entry->dest);
+ else if (compare_orig(entry->src, src))
+ return sprintf(buff, "TQ %pM %d, ", entry->dest,
+ entry->quality);
+
+ return 0;
+}
+
+int vis_seq_print_text(struct seq_file *seq, void *offset)
+{
+ struct hlist_node *walk;
+ struct hlist_head *head;
+ struct element_t *bucket;
+ struct vis_info *info;
+ struct vis_packet *packet;
+ struct vis_info_entry *entries;
+ struct net_device *net_dev = (struct net_device *)seq->private;
+ struct bat_priv *bat_priv = netdev_priv(net_dev);
+ struct hashtable_t *hash = bat_priv->vis_hash;
+ HLIST_HEAD(vis_if_list);
+ struct if_list_entry *entry;
+ struct hlist_node *pos, *n;
+ int i, j;
+ int vis_server = atomic_read(&bat_priv->vis_mode);
+ size_t buff_pos, buf_size;
+ char *buff;
+ int compare;
+
+ if ((!bat_priv->primary_if) ||
+ (vis_server == VIS_TYPE_CLIENT_UPDATE))
+ return 0;
+
+ buf_size = 1;
+ /* Estimate length */
+ spin_lock_bh(&bat_priv->vis_hash_lock);
+ for (i = 0; i < hash->size; i++) {
+ head = &hash->table[i];
+
+ hlist_for_each_entry(bucket, walk, head, hlist) {
+ info = bucket->data;
+ packet = (struct vis_packet *)info->skb_packet->data;
+ entries = (struct vis_info_entry *)
+ ((char *)packet + sizeof(struct vis_packet));
+
+ for (j = 0; j < packet->entries; j++) {
+ if (entries[j].quality == 0)
+ continue;
+ compare =
+ compare_orig(entries[j].src, packet->vis_orig);
+ vis_data_insert_interface(entries[j].src,
+ &vis_if_list,
+ compare);
+ }
+
+ hlist_for_each_entry(entry, pos, &vis_if_list, list) {
+ buf_size += 18 + 26 * packet->entries;
+
+ /* add primary/secondary records */
+ if (compare_orig(entry->addr, packet->vis_orig))
+ buf_size +=
+ vis_data_count_prim_sec(&vis_if_list);
+
+ buf_size += 1;
+ }
+
+ hlist_for_each_entry_safe(entry, pos, n, &vis_if_list,
+ list) {
+ hlist_del(&entry->list);
+ kfree(entry);
+ }
+ }
+ }
+
+ buff = kmalloc(buf_size, GFP_ATOMIC);
+ if (!buff) {
+ spin_unlock_bh(&bat_priv->vis_hash_lock);
+ return -ENOMEM;
+ }
+ buff[0] = '\0';
+ buff_pos = 0;
+
+ for (i = 0; i < hash->size; i++) {
+ head = &hash->table[i];
+
+ hlist_for_each_entry(bucket, walk, head, hlist) {
+ info = bucket->data;
+ packet = (struct vis_packet *)info->skb_packet->data;
+ entries = (struct vis_info_entry *)
+ ((char *)packet + sizeof(struct vis_packet));
+
+ for (j = 0; j < packet->entries; j++) {
+ if (entries[j].quality == 0)
+ continue;
+ compare =
+ compare_orig(entries[j].src, packet->vis_orig);
+ vis_data_insert_interface(entries[j].src,
+ &vis_if_list,
+ compare);
+ }
+
+ hlist_for_each_entry(entry, pos, &vis_if_list, list) {
+ buff_pos += sprintf(buff + buff_pos, "%pM,",
+ entry->addr);
+
+ for (i = 0; i < packet->entries; i++)
+ buff_pos += vis_data_read_entry(
+ buff + buff_pos,
+ &entries[i],
+ entry->addr,
+ entry->primary);
+
+ /* add primary/secondary records */
+ if (compare_orig(entry->addr, packet->vis_orig))
+ buff_pos +=
+ vis_data_read_prim_sec(buff + buff_pos,
+ &vis_if_list);
+
+ buff_pos += sprintf(buff + buff_pos, "\n");
+ }
+
+ hlist_for_each_entry_safe(entry, pos, n, &vis_if_list,
+ list) {
+ hlist_del(&entry->list);
+ kfree(entry);
+ }
+ }
+ }
+
+ spin_unlock_bh(&bat_priv->vis_hash_lock);
+
+ seq_printf(seq, "%s", buff);
+ kfree(buff);
+
+ return 0;
+}
+
+/* add the info packet to the send list, if it was not
+ * already linked in. */
+static void send_list_add(struct bat_priv *bat_priv, struct vis_info *info)
+{
+ if (list_empty(&info->send_list)) {
+ kref_get(&info->refcount);
+ list_add_tail(&info->send_list, &bat_priv->vis_send_list);
+ }
+}
+
+/* delete the info packet from the send list, if it was
+ * linked in. */
+static void send_list_del(struct vis_info *info)
+{
+ if (!list_empty(&info->send_list)) {
+ list_del_init(&info->send_list);
+ kref_put(&info->refcount, free_info);
+ }
+}
+
+/* tries to add one entry to the receive list. */
+static void recv_list_add(struct bat_priv *bat_priv,
+ struct list_head *recv_list, char *mac)
+{
+ struct recvlist_node *entry;
+
+ entry = kmalloc(sizeof(struct recvlist_node), GFP_ATOMIC);
+ if (!entry)
+ return;
+
+ memcpy(entry->mac, mac, ETH_ALEN);
+ spin_lock_bh(&bat_priv->vis_list_lock);
+ list_add_tail(&entry->list, recv_list);
+ spin_unlock_bh(&bat_priv->vis_list_lock);
+}
+
+/* returns 1 if this mac is in the recv_list */
+static int recv_list_is_in(struct bat_priv *bat_priv,
+ struct list_head *recv_list, char *mac)
+{
+ struct recvlist_node *entry;
+
+ spin_lock_bh(&bat_priv->vis_list_lock);
+ list_for_each_entry(entry, recv_list, list) {
+ if (memcmp(entry->mac, mac, ETH_ALEN) == 0) {
+ spin_unlock_bh(&bat_priv->vis_list_lock);
+ return 1;
+ }
+ }
+ spin_unlock_bh(&bat_priv->vis_list_lock);
+ return 0;
+}
+
+/* try to add the packet to the vis_hash. return NULL if invalid (e.g. too old,
+ * broken.. ). vis hash must be locked outside. is_new is set when the packet
+ * is newer than old entries in the hash. */
+static struct vis_info *add_packet(struct bat_priv *bat_priv,
+ struct vis_packet *vis_packet,
+ int vis_info_len, int *is_new,
+ int make_broadcast)
+{
+ struct vis_info *info, *old_info;
+ struct vis_packet *search_packet, *old_packet;
+ struct vis_info search_elem;
+ struct vis_packet *packet;
+ int hash_added;
+
+ *is_new = 0;
+ /* sanity check */
+ if (!bat_priv->vis_hash)
+ return NULL;
+
+ /* see if the packet is already in vis_hash */
+ search_elem.skb_packet = dev_alloc_skb(sizeof(struct vis_packet));
+ if (!search_elem.skb_packet)
+ return NULL;
+ search_packet = (struct vis_packet *)skb_put(search_elem.skb_packet,
+ sizeof(struct vis_packet));
+
+ memcpy(search_packet->vis_orig, vis_packet->vis_orig, ETH_ALEN);
+ old_info = hash_find(bat_priv->vis_hash, vis_info_cmp, vis_info_choose,
+ &search_elem);
+ kfree_skb(search_elem.skb_packet);
+
+ if (old_info) {
+ old_packet = (struct vis_packet *)old_info->skb_packet->data;
+ if (!seq_after(ntohl(vis_packet->seqno),
+ ntohl(old_packet->seqno))) {
+ if (old_packet->seqno == vis_packet->seqno) {
+ recv_list_add(bat_priv, &old_info->recv_list,
+ vis_packet->sender_orig);
+ return old_info;
+ } else {
+ /* newer packet is already in hash. */
+ return NULL;
+ }
+ }
+ /* remove old entry */
+ hash_remove(bat_priv->vis_hash, vis_info_cmp, vis_info_choose,
+ old_info);
+ send_list_del(old_info);
+ kref_put(&old_info->refcount, free_info);
+ }
+
+ info = kmalloc(sizeof(struct vis_info), GFP_ATOMIC);
+ if (!info)
+ return NULL;
+
+ info->skb_packet = dev_alloc_skb(sizeof(struct vis_packet) +
+ vis_info_len + sizeof(struct ethhdr));
+ if (!info->skb_packet) {
+ kfree(info);
+ return NULL;
+ }
+ skb_reserve(info->skb_packet, sizeof(struct ethhdr));
+ packet = (struct vis_packet *)skb_put(info->skb_packet,
+ sizeof(struct vis_packet) +
+ vis_info_len);
+
+ kref_init(&info->refcount);
+ INIT_LIST_HEAD(&info->send_list);
+ INIT_LIST_HEAD(&info->recv_list);
+ info->first_seen = jiffies;
+ info->bat_priv = bat_priv;
+ memcpy(packet, vis_packet, sizeof(struct vis_packet) + vis_info_len);
+
+ /* initialize and add new packet. */
+ *is_new = 1;
+
+ /* Make it a broadcast packet, if required */
+ if (make_broadcast)
+ memcpy(packet->target_orig, broadcast_addr, ETH_ALEN);
+
+ /* repair if entries is longer than packet. */
+ if (packet->entries * sizeof(struct vis_info_entry) > vis_info_len)
+ packet->entries = vis_info_len / sizeof(struct vis_info_entry);
+
+ recv_list_add(bat_priv, &info->recv_list, packet->sender_orig);
+
+ /* try to add it */
+ hash_added = hash_add(bat_priv->vis_hash, vis_info_cmp, vis_info_choose,
+ info);
+ if (hash_added < 0) {
+ /* did not work (for some reason) */
+ kref_put(&old_info->refcount, free_info);
+ info = NULL;
+ }
+
+ return info;
+}
+
+/* handle the server sync packet, forward if needed. */
+void receive_server_sync_packet(struct bat_priv *bat_priv,
+ struct vis_packet *vis_packet,
+ int vis_info_len)
+{
+ struct vis_info *info;
+ int is_new, make_broadcast;
+ int vis_server = atomic_read(&bat_priv->vis_mode);
+
+ make_broadcast = (vis_server == VIS_TYPE_SERVER_SYNC);
+
+ spin_lock_bh(&bat_priv->vis_hash_lock);
+ info = add_packet(bat_priv, vis_packet, vis_info_len,
+ &is_new, make_broadcast);
+ if (!info)
+ goto end;
+
+ /* only if we are server ourselves and packet is newer than the one in
+ * hash.*/
+ if (vis_server == VIS_TYPE_SERVER_SYNC && is_new)
+ send_list_add(bat_priv, info);
+end:
+ spin_unlock_bh(&bat_priv->vis_hash_lock);
+}
+
+/* handle an incoming client update packet and schedule forward if needed. */
+void receive_client_update_packet(struct bat_priv *bat_priv,
+ struct vis_packet *vis_packet,
+ int vis_info_len)
+{
+ struct vis_info *info;
+ struct vis_packet *packet;
+ int is_new;
+ int vis_server = atomic_read(&bat_priv->vis_mode);
+ int are_target = 0;
+
+ /* clients shall not broadcast. */
+ if (is_broadcast_ether_addr(vis_packet->target_orig))
+ return;
+
+ /* Are we the target for this VIS packet? */
+ if (vis_server == VIS_TYPE_SERVER_SYNC &&
+ is_my_mac(vis_packet->target_orig))
+ are_target = 1;
+
+ spin_lock_bh(&bat_priv->vis_hash_lock);
+ info = add_packet(bat_priv, vis_packet, vis_info_len,
+ &is_new, are_target);
+
+ if (!info)
+ goto end;
+ /* note that outdated packets will be dropped at this point. */
+
+ packet = (struct vis_packet *)info->skb_packet->data;
+
+ /* send only if we're the target server or ... */
+ if (are_target && is_new) {
+ packet->vis_type = VIS_TYPE_SERVER_SYNC; /* upgrade! */
+ send_list_add(bat_priv, info);
+
+ /* ... we're not the recipient (and thus need to forward). */
+ } else if (!is_my_mac(packet->target_orig)) {
+ send_list_add(bat_priv, info);
+ }
+
+end:
+ spin_unlock_bh(&bat_priv->vis_hash_lock);
+}
+
+/* Walk the originators and find the VIS server with the best tq. Set the packet
+ * address to its address and return the best_tq.
+ *
+ * Must be called with the originator hash locked */
+static int find_best_vis_server(struct bat_priv *bat_priv,
+ struct vis_info *info)
+{
+ struct hashtable_t *hash = bat_priv->orig_hash;
+ struct hlist_node *walk;
+ struct hlist_head *head;
+ struct element_t *bucket;
+ struct orig_node *orig_node;
+ struct vis_packet *packet;
+ int best_tq = -1, i;
+
+ packet = (struct vis_packet *)info->skb_packet->data;
+
+ for (i = 0; i < hash->size; i++) {
+ head = &hash->table[i];
+
+ hlist_for_each_entry(bucket, walk, head, hlist) {
+ orig_node = bucket->data;
+ if ((orig_node) && (orig_node->router) &&
+ (orig_node->flags & VIS_SERVER) &&
+ (orig_node->router->tq_avg > best_tq)) {
+ best_tq = orig_node->router->tq_avg;
+ memcpy(packet->target_orig, orig_node->orig,
+ ETH_ALEN);
+ }
+ }
+ }
+
+ return best_tq;
+}
+
+/* Return true if the vis packet is full. */
+static bool vis_packet_full(struct vis_info *info)
+{
+ struct vis_packet *packet;
+ packet = (struct vis_packet *)info->skb_packet->data;
+
+ if (MAX_VIS_PACKET_SIZE / sizeof(struct vis_info_entry)
+ < packet->entries + 1)
+ return true;
+ return false;
+}
+
+/* generates a packet of own vis data,
+ * returns 0 on success, -1 if no packet could be generated */
+static int generate_vis_packet(struct bat_priv *bat_priv)
+{
+ struct hashtable_t *hash = bat_priv->orig_hash;
+ struct hlist_node *walk;
+ struct hlist_head *head;
+ struct element_t *bucket;
+ struct orig_node *orig_node;
+ struct neigh_node *neigh_node;
+ struct vis_info *info = (struct vis_info *)bat_priv->my_vis_info;
+ struct vis_packet *packet = (struct vis_packet *)info->skb_packet->data;
+ struct vis_info_entry *entry;
+ struct hna_local_entry *hna_local_entry;
+ int best_tq = -1, i;
+
+ info->first_seen = jiffies;
+ packet->vis_type = atomic_read(&bat_priv->vis_mode);
+
+ spin_lock_bh(&bat_priv->orig_hash_lock);
+ memcpy(packet->target_orig, broadcast_addr, ETH_ALEN);
+ packet->ttl = TTL;
+ packet->seqno = htonl(ntohl(packet->seqno) + 1);
+ packet->entries = 0;
+ skb_trim(info->skb_packet, sizeof(struct vis_packet));
+
+ if (packet->vis_type == VIS_TYPE_CLIENT_UPDATE) {
+ best_tq = find_best_vis_server(bat_priv, info);
+
+ if (best_tq < 0) {
+ spin_unlock_bh(&bat_priv->orig_hash_lock);
+ return -1;
+ }
+ }
+
+ for (i = 0; i < hash->size; i++) {
+ head = &hash->table[i];
+
+ hlist_for_each_entry(bucket, walk, head, hlist) {
+ orig_node = bucket->data;
+ neigh_node = orig_node->router;
+
+ if (!neigh_node)
+ continue;
+
+ if (!compare_orig(neigh_node->addr, orig_node->orig))
+ continue;
+
+ if (neigh_node->if_incoming->if_status != IF_ACTIVE)
+ continue;
+
+ if (neigh_node->tq_avg < 1)
+ continue;
+
+ /* fill one entry into buffer. */
+ entry = (struct vis_info_entry *)
+ skb_put(info->skb_packet, sizeof(*entry));
+ memcpy(entry->src,
+ neigh_node->if_incoming->net_dev->dev_addr,
+ ETH_ALEN);
+ memcpy(entry->dest, orig_node->orig, ETH_ALEN);
+ entry->quality = neigh_node->tq_avg;
+ packet->entries++;
+
+ if (vis_packet_full(info)) {
+ spin_unlock_bh(&bat_priv->orig_hash_lock);
+ return 0;
+ }
+ }
+ }
+
+ spin_unlock_bh(&bat_priv->orig_hash_lock);
+
+ hash = bat_priv->hna_local_hash;
+
+ spin_lock_bh(&bat_priv->hna_lhash_lock);
+ for (i = 0; i < hash->size; i++) {
+ head = &hash->table[i];
+
+ hlist_for_each_entry(bucket, walk, head, hlist) {
+ hna_local_entry = bucket->data;
+ entry = (struct vis_info_entry *)
+ skb_put(info->skb_packet,
+ sizeof(*entry));
+ memset(entry->src, 0, ETH_ALEN);
+ memcpy(entry->dest, hna_local_entry->addr, ETH_ALEN);
+ entry->quality = 0; /* 0 means HNA */
+ packet->entries++;
+
+ if (vis_packet_full(info)) {
+ spin_unlock_bh(&bat_priv->hna_lhash_lock);
+ return 0;
+ }
+ }
+ }
+
+ spin_unlock_bh(&bat_priv->hna_lhash_lock);
+ return 0;
+}
+
+/* free old vis packets. Must be called with this vis_hash_lock
+ * held */
+static void purge_vis_packets(struct bat_priv *bat_priv)
+{
+ int i;
+ struct hashtable_t *hash = bat_priv->vis_hash;
+ struct hlist_node *walk, *safe;
+ struct hlist_head *head;
+ struct element_t *bucket;
+ struct vis_info *info;
+
+ for (i = 0; i < hash->size; i++) {
+ head = &hash->table[i];
+
+ hlist_for_each_entry_safe(bucket, walk, safe, head, hlist) {
+ info = bucket->data;
+
+ /* never purge own data. */
+ if (info == bat_priv->my_vis_info)
+ continue;
+
+ if (time_after(jiffies,
+ info->first_seen + VIS_TIMEOUT * HZ)) {
+ hlist_del(walk);
+ kfree(bucket);
+ send_list_del(info);
+ kref_put(&info->refcount, free_info);
+ }
+ }
+ }
+}
+
+static void broadcast_vis_packet(struct bat_priv *bat_priv,
+ struct vis_info *info)
+{
+ struct hashtable_t *hash = bat_priv->orig_hash;
+ struct hlist_node *walk;
+ struct hlist_head *head;
+ struct element_t *bucket;
+ struct orig_node *orig_node;
+ struct vis_packet *packet;
+ struct sk_buff *skb;
+ struct batman_if *batman_if;
+ uint8_t dstaddr[ETH_ALEN];
+ int i;
+
+
+ spin_lock_bh(&bat_priv->orig_hash_lock);
+ packet = (struct vis_packet *)info->skb_packet->data;
+
+ /* send to all routers in range. */
+ for (i = 0; i < hash->size; i++) {
+ head = &hash->table[i];
+
+ hlist_for_each_entry(bucket, walk, head, hlist) {
+ orig_node = bucket->data;
+
+ /* if it's a vis server and reachable, send it. */
+ if ((!orig_node) || (!orig_node->router))
+ continue;
+ if (!(orig_node->flags & VIS_SERVER))
+ continue;
+ /* don't send it if we already received the packet from
+ * this node. */
+ if (recv_list_is_in(bat_priv, &info->recv_list,
+ orig_node->orig))
+ continue;
+
+ memcpy(packet->target_orig, orig_node->orig, ETH_ALEN);
+ batman_if = orig_node->router->if_incoming;
+ memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
+ spin_unlock_bh(&bat_priv->orig_hash_lock);
+
+ skb = skb_clone(info->skb_packet, GFP_ATOMIC);
+ if (skb)
+ send_skb_packet(skb, batman_if, dstaddr);
+
+ spin_lock_bh(&bat_priv->orig_hash_lock);
+ }
+
+ }
+
+ spin_unlock_bh(&bat_priv->orig_hash_lock);
+}
+
+static void unicast_vis_packet(struct bat_priv *bat_priv,
+ struct vis_info *info)
+{
+ struct orig_node *orig_node;
+ struct sk_buff *skb;
+ struct vis_packet *packet;
+ struct batman_if *batman_if;
+ uint8_t dstaddr[ETH_ALEN];
+
+ spin_lock_bh(&bat_priv->orig_hash_lock);
+ packet = (struct vis_packet *)info->skb_packet->data;
+ orig_node = ((struct orig_node *)hash_find(bat_priv->orig_hash,
+ compare_orig, choose_orig,
+ packet->target_orig));
+
+ if ((!orig_node) || (!orig_node->router))
+ goto out;
+
+ /* don't lock while sending the packets ... we therefore
+ * copy the required data before sending */
+ batman_if = orig_node->router->if_incoming;
+ memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
+ spin_unlock_bh(&bat_priv->orig_hash_lock);
+
+ skb = skb_clone(info->skb_packet, GFP_ATOMIC);
+ if (skb)
+ send_skb_packet(skb, batman_if, dstaddr);
+
+ return;
+
+out:
+ spin_unlock_bh(&bat_priv->orig_hash_lock);
+}
+
+/* only send one vis packet. called from send_vis_packets() */
+static void send_vis_packet(struct bat_priv *bat_priv, struct vis_info *info)
+{
+ struct vis_packet *packet;
+
+ packet = (struct vis_packet *)info->skb_packet->data;
+ if (packet->ttl < 2) {
+ pr_debug("Error - can't send vis packet: ttl exceeded\n");
+ return;
+ }
+
+ memcpy(packet->sender_orig, bat_priv->primary_if->net_dev->dev_addr,
+ ETH_ALEN);
+ packet->ttl--;
+
+ if (is_broadcast_ether_addr(packet->target_orig))
+ broadcast_vis_packet(bat_priv, info);
+ else
+ unicast_vis_packet(bat_priv, info);
+ packet->ttl++; /* restore TTL */
+}
+
+/* called from timer; send (and maybe generate) vis packet. */
+static void send_vis_packets(struct work_struct *work)
+{
+ struct delayed_work *delayed_work =
+ container_of(work, struct delayed_work, work);
+ struct bat_priv *bat_priv =
+ container_of(delayed_work, struct bat_priv, vis_work);
+ struct vis_info *info, *temp;
+
+ spin_lock_bh(&bat_priv->vis_hash_lock);
+ purge_vis_packets(bat_priv);
+
+ if (generate_vis_packet(bat_priv) == 0) {
+ /* schedule if generation was successful */
+ send_list_add(bat_priv, bat_priv->my_vis_info);
+ }
+
+ list_for_each_entry_safe(info, temp, &bat_priv->vis_send_list,
+ send_list) {
+
+ kref_get(&info->refcount);
+ spin_unlock_bh(&bat_priv->vis_hash_lock);
+
+ if (bat_priv->primary_if)
+ send_vis_packet(bat_priv, info);
+
+ spin_lock_bh(&bat_priv->vis_hash_lock);
+ send_list_del(info);
+ kref_put(&info->refcount, free_info);
+ }
+ spin_unlock_bh(&bat_priv->vis_hash_lock);
+ start_vis_timer(bat_priv);
+}
+
+/* init the vis server. this may only be called when if_list is already
+ * initialized (e.g. bat0 is initialized, interfaces have been added) */
+int vis_init(struct bat_priv *bat_priv)
+{
+ struct vis_packet *packet;
+ int hash_added;
+
+ if (bat_priv->vis_hash)
+ return 1;
+
+ spin_lock_bh(&bat_priv->vis_hash_lock);
+
+ bat_priv->vis_hash = hash_new(256);
+ if (!bat_priv->vis_hash) {
+ pr_err("Can't initialize vis_hash\n");
+ goto err;
+ }
+
+ bat_priv->my_vis_info = kmalloc(MAX_VIS_PACKET_SIZE, GFP_ATOMIC);
+ if (!bat_priv->my_vis_info) {
+ pr_err("Can't initialize vis packet\n");
+ goto err;
+ }
+
+ bat_priv->my_vis_info->skb_packet = dev_alloc_skb(
+ sizeof(struct vis_packet) +
+ MAX_VIS_PACKET_SIZE +
+ sizeof(struct ethhdr));
+ if (!bat_priv->my_vis_info->skb_packet)
+ goto free_info;
+
+ skb_reserve(bat_priv->my_vis_info->skb_packet, sizeof(struct ethhdr));
+ packet = (struct vis_packet *)skb_put(
+ bat_priv->my_vis_info->skb_packet,
+ sizeof(struct vis_packet));
+
+ /* prefill the vis info */
+ bat_priv->my_vis_info->first_seen = jiffies -
+ msecs_to_jiffies(VIS_INTERVAL);
+ INIT_LIST_HEAD(&bat_priv->my_vis_info->recv_list);
+ INIT_LIST_HEAD(&bat_priv->my_vis_info->send_list);
+ kref_init(&bat_priv->my_vis_info->refcount);
+ bat_priv->my_vis_info->bat_priv = bat_priv;
+ packet->version = COMPAT_VERSION;
+ packet->packet_type = BAT_VIS;
+ packet->ttl = TTL;
+ packet->seqno = 0;
+ packet->entries = 0;
+
+ INIT_LIST_HEAD(&bat_priv->vis_send_list);
+
+ hash_added = hash_add(bat_priv->vis_hash, vis_info_cmp, vis_info_choose,
+ bat_priv->my_vis_info);
+ if (hash_added < 0) {
+ pr_err("Can't add own vis packet into hash\n");
+ /* not in hash, need to remove it manually. */
+ kref_put(&bat_priv->my_vis_info->refcount, free_info);
+ goto err;
+ }
+
+ spin_unlock_bh(&bat_priv->vis_hash_lock);
+ start_vis_timer(bat_priv);
+ return 1;
+
+free_info:
+ kfree(bat_priv->my_vis_info);
+ bat_priv->my_vis_info = NULL;
+err:
+ spin_unlock_bh(&bat_priv->vis_hash_lock);
+ vis_quit(bat_priv);
+ return 0;
+}
+
+/* Decrease the reference count on a hash item info */
+static void free_info_ref(void *data, void *arg)
+{
+ struct vis_info *info = data;
+
+ send_list_del(info);
+ kref_put(&info->refcount, free_info);
+}
+
+/* shutdown vis-server */
+void vis_quit(struct bat_priv *bat_priv)
+{
+ if (!bat_priv->vis_hash)
+ return;
+
+ cancel_delayed_work_sync(&bat_priv->vis_work);
+
+ spin_lock_bh(&bat_priv->vis_hash_lock);
+ /* properly remove, kill timers ... */
+ hash_delete(bat_priv->vis_hash, free_info_ref, NULL);
+ bat_priv->vis_hash = NULL;
+ bat_priv->my_vis_info = NULL;
+ spin_unlock_bh(&bat_priv->vis_hash_lock);
+}
+
+/* schedule packets for (re)transmission */
+static void start_vis_timer(struct bat_priv *bat_priv)
+{
+ INIT_DELAYED_WORK(&bat_priv->vis_work, send_vis_packets);
+ queue_delayed_work(bat_event_workqueue, &bat_priv->vis_work,
+ msecs_to_jiffies(VIS_INTERVAL));
+}