|
|
@@ -0,0 +1,1066 @@
|
|
|
+/* Copyright (C) 2011-2012 B.A.T.M.A.N. contributors:
|
|
|
+ *
|
|
|
+ * Antonio Quartulli
|
|
|
+ *
|
|
|
+ * 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 <linux/if_ether.h>
|
|
|
+#include <linux/if_arp.h>
|
|
|
+#include <net/arp.h>
|
|
|
+
|
|
|
+#include "main.h"
|
|
|
+#include "hash.h"
|
|
|
+#include "distributed-arp-table.h"
|
|
|
+#include "hard-interface.h"
|
|
|
+#include "originator.h"
|
|
|
+#include "send.h"
|
|
|
+#include "types.h"
|
|
|
+#include "translation-table.h"
|
|
|
+#include "unicast.h"
|
|
|
+
|
|
|
+static void batadv_dat_purge(struct work_struct *work);
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_dat_start_timer - initialise the DAT periodic worker
|
|
|
+ * @bat_priv: the bat priv with all the soft interface information
|
|
|
+ */
|
|
|
+static void batadv_dat_start_timer(struct batadv_priv *bat_priv)
|
|
|
+{
|
|
|
+ INIT_DELAYED_WORK(&bat_priv->dat.work, batadv_dat_purge);
|
|
|
+ queue_delayed_work(batadv_event_workqueue, &bat_priv->dat.work,
|
|
|
+ msecs_to_jiffies(10000));
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_dat_entry_free_ref - decrements the dat_entry refcounter and possibly
|
|
|
+ * free it
|
|
|
+ * @dat_entry: the oentry to free
|
|
|
+ */
|
|
|
+static void batadv_dat_entry_free_ref(struct batadv_dat_entry *dat_entry)
|
|
|
+{
|
|
|
+ if (atomic_dec_and_test(&dat_entry->refcount))
|
|
|
+ kfree_rcu(dat_entry, rcu);
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_dat_to_purge - checks whether a dat_entry has to be purged or not
|
|
|
+ * @dat_entry: the entry to check
|
|
|
+ *
|
|
|
+ * Returns true if the entry has to be purged now, false otherwise
|
|
|
+ */
|
|
|
+static bool batadv_dat_to_purge(struct batadv_dat_entry *dat_entry)
|
|
|
+{
|
|
|
+ return batadv_has_timed_out(dat_entry->last_update,
|
|
|
+ BATADV_DAT_ENTRY_TIMEOUT);
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * __batadv_dat_purge - delete entries from the DAT local storage
|
|
|
+ * @bat_priv: the bat priv with all the soft interface information
|
|
|
+ * @to_purge: function in charge to decide whether an entry has to be purged or
|
|
|
+ * not. This function takes the dat_entry as argument and has to
|
|
|
+ * returns a boolean value: true is the entry has to be deleted,
|
|
|
+ * false otherwise
|
|
|
+ *
|
|
|
+ * Loops over each entry in the DAT local storage and delete it if and only if
|
|
|
+ * the to_purge function passed as argument returns true
|
|
|
+ */
|
|
|
+static void __batadv_dat_purge(struct batadv_priv *bat_priv,
|
|
|
+ bool (*to_purge)(struct batadv_dat_entry *))
|
|
|
+{
|
|
|
+ spinlock_t *list_lock; /* protects write access to the hash lists */
|
|
|
+ struct batadv_dat_entry *dat_entry;
|
|
|
+ struct hlist_node *node, *node_tmp;
|
|
|
+ struct hlist_head *head;
|
|
|
+ uint32_t i;
|
|
|
+
|
|
|
+ if (!bat_priv->dat.hash)
|
|
|
+ return;
|
|
|
+
|
|
|
+ for (i = 0; i < bat_priv->dat.hash->size; i++) {
|
|
|
+ head = &bat_priv->dat.hash->table[i];
|
|
|
+ list_lock = &bat_priv->dat.hash->list_locks[i];
|
|
|
+
|
|
|
+ spin_lock_bh(list_lock);
|
|
|
+ hlist_for_each_entry_safe(dat_entry, node, node_tmp, head,
|
|
|
+ hash_entry) {
|
|
|
+ /* if an helper function has been passed as parameter,
|
|
|
+ * ask it if the entry has to be purged or not
|
|
|
+ */
|
|
|
+ if (to_purge && !to_purge(dat_entry))
|
|
|
+ continue;
|
|
|
+
|
|
|
+ hlist_del_rcu(node);
|
|
|
+ batadv_dat_entry_free_ref(dat_entry);
|
|
|
+ }
|
|
|
+ spin_unlock_bh(list_lock);
|
|
|
+ }
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_dat_purge - periodic task that deletes old entries from the local DAT
|
|
|
+ * hash table
|
|
|
+ * @work: kernel work struct
|
|
|
+ */
|
|
|
+static void batadv_dat_purge(struct work_struct *work)
|
|
|
+{
|
|
|
+ struct delayed_work *delayed_work;
|
|
|
+ struct batadv_priv_dat *priv_dat;
|
|
|
+ struct batadv_priv *bat_priv;
|
|
|
+
|
|
|
+ delayed_work = container_of(work, struct delayed_work, work);
|
|
|
+ priv_dat = container_of(delayed_work, struct batadv_priv_dat, work);
|
|
|
+ bat_priv = container_of(priv_dat, struct batadv_priv, dat);
|
|
|
+
|
|
|
+ __batadv_dat_purge(bat_priv, batadv_dat_to_purge);
|
|
|
+ batadv_dat_start_timer(bat_priv);
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_compare_dat - comparing function used in the local DAT hash table
|
|
|
+ * @node: node in the local table
|
|
|
+ * @data2: second object to compare the node to
|
|
|
+ *
|
|
|
+ * Returns 1 if the two entry are the same, 0 otherwise
|
|
|
+ */
|
|
|
+static int batadv_compare_dat(const struct hlist_node *node, const void *data2)
|
|
|
+{
|
|
|
+ const void *data1 = container_of(node, struct batadv_dat_entry,
|
|
|
+ hash_entry);
|
|
|
+
|
|
|
+ return (memcmp(data1, data2, sizeof(__be32)) == 0 ? 1 : 0);
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_arp_hw_src - extract the hw_src field from an ARP packet
|
|
|
+ * @skb: ARP packet
|
|
|
+ * @hdr_size: size of the possible header before the ARP packet
|
|
|
+ *
|
|
|
+ * Returns the value of the hw_src field in the ARP packet
|
|
|
+ */
|
|
|
+static uint8_t *batadv_arp_hw_src(struct sk_buff *skb, int hdr_size)
|
|
|
+{
|
|
|
+ uint8_t *addr;
|
|
|
+
|
|
|
+ addr = (uint8_t *)(skb->data + hdr_size);
|
|
|
+ addr += ETH_HLEN + sizeof(struct arphdr);
|
|
|
+
|
|
|
+ return addr;
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_arp_ip_src - extract the ip_src field from an ARP packet
|
|
|
+ * @skb: ARP packet
|
|
|
+ * @hdr_size: size of the possible header before the ARP packet
|
|
|
+ *
|
|
|
+ * Returns the value of the ip_src field in the ARP packet
|
|
|
+ */
|
|
|
+static __be32 batadv_arp_ip_src(struct sk_buff *skb, int hdr_size)
|
|
|
+{
|
|
|
+ return *(__be32 *)(batadv_arp_hw_src(skb, hdr_size) + ETH_ALEN);
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_arp_hw_dst - extract the hw_dst field from an ARP packet
|
|
|
+ * @skb: ARP packet
|
|
|
+ * @hdr_size: size of the possible header before the ARP packet
|
|
|
+ *
|
|
|
+ * Returns the value of the hw_dst field in the ARP packet
|
|
|
+ */
|
|
|
+static uint8_t *batadv_arp_hw_dst(struct sk_buff *skb, int hdr_size)
|
|
|
+{
|
|
|
+ return batadv_arp_hw_src(skb, hdr_size) + ETH_ALEN + 4;
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_arp_ip_dst - extract the ip_dst field from an ARP packet
|
|
|
+ * @skb: ARP packet
|
|
|
+ * @hdr_size: size of the possible header before the ARP packet
|
|
|
+ *
|
|
|
+ * Returns the value of the ip_dst field in the ARP packet
|
|
|
+ */
|
|
|
+static __be32 batadv_arp_ip_dst(struct sk_buff *skb, int hdr_size)
|
|
|
+{
|
|
|
+ return *(__be32 *)(batadv_arp_hw_src(skb, hdr_size) + ETH_ALEN * 2 + 4);
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_hash_dat - compute the hash value for an IP address
|
|
|
+ * @data: data to hash
|
|
|
+ * @size: size of the hash table
|
|
|
+ *
|
|
|
+ * Returns the selected index in the hash table for the given data
|
|
|
+ */
|
|
|
+static uint32_t batadv_hash_dat(const void *data, uint32_t size)
|
|
|
+{
|
|
|
+ const unsigned char *key = data;
|
|
|
+ uint32_t hash = 0;
|
|
|
+ size_t i;
|
|
|
+
|
|
|
+ for (i = 0; i < 4; i++) {
|
|
|
+ hash += key[i];
|
|
|
+ hash += (hash << 10);
|
|
|
+ hash ^= (hash >> 6);
|
|
|
+ }
|
|
|
+
|
|
|
+ hash += (hash << 3);
|
|
|
+ hash ^= (hash >> 11);
|
|
|
+ hash += (hash << 15);
|
|
|
+
|
|
|
+ return hash % size;
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_dat_entry_hash_find - looks for a given dat_entry in the local hash
|
|
|
+ * table
|
|
|
+ * @bat_priv: the bat priv with all the soft interface information
|
|
|
+ * @ip: search key
|
|
|
+ *
|
|
|
+ * Returns the dat_entry if found, NULL otherwise
|
|
|
+ */
|
|
|
+static struct batadv_dat_entry *
|
|
|
+batadv_dat_entry_hash_find(struct batadv_priv *bat_priv, __be32 ip)
|
|
|
+{
|
|
|
+ struct hlist_head *head;
|
|
|
+ struct hlist_node *node;
|
|
|
+ struct batadv_dat_entry *dat_entry, *dat_entry_tmp = NULL;
|
|
|
+ struct batadv_hashtable *hash = bat_priv->dat.hash;
|
|
|
+ uint32_t index;
|
|
|
+
|
|
|
+ if (!hash)
|
|
|
+ return NULL;
|
|
|
+
|
|
|
+ index = batadv_hash_dat(&ip, hash->size);
|
|
|
+ head = &hash->table[index];
|
|
|
+
|
|
|
+ rcu_read_lock();
|
|
|
+ hlist_for_each_entry_rcu(dat_entry, node, head, hash_entry) {
|
|
|
+ if (dat_entry->ip != ip)
|
|
|
+ continue;
|
|
|
+
|
|
|
+ if (!atomic_inc_not_zero(&dat_entry->refcount))
|
|
|
+ continue;
|
|
|
+
|
|
|
+ dat_entry_tmp = dat_entry;
|
|
|
+ break;
|
|
|
+ }
|
|
|
+ rcu_read_unlock();
|
|
|
+
|
|
|
+ return dat_entry_tmp;
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_dat_entry_add - add a new dat entry or update it if already exists
|
|
|
+ * @bat_priv: the bat priv with all the soft interface information
|
|
|
+ * @ip: ipv4 to add/edit
|
|
|
+ * @mac_addr: mac address to assign to the given ipv4
|
|
|
+ */
|
|
|
+static void batadv_dat_entry_add(struct batadv_priv *bat_priv, __be32 ip,
|
|
|
+ uint8_t *mac_addr)
|
|
|
+{
|
|
|
+ struct batadv_dat_entry *dat_entry;
|
|
|
+ int hash_added;
|
|
|
+
|
|
|
+ dat_entry = batadv_dat_entry_hash_find(bat_priv, ip);
|
|
|
+ /* if this entry is already known, just update it */
|
|
|
+ if (dat_entry) {
|
|
|
+ if (!batadv_compare_eth(dat_entry->mac_addr, mac_addr))
|
|
|
+ memcpy(dat_entry->mac_addr, mac_addr, ETH_ALEN);
|
|
|
+ dat_entry->last_update = jiffies;
|
|
|
+ batadv_dbg(BATADV_DBG_DAT, bat_priv,
|
|
|
+ "Entry updated: %pI4 %pM\n", &dat_entry->ip,
|
|
|
+ dat_entry->mac_addr);
|
|
|
+ goto out;
|
|
|
+ }
|
|
|
+
|
|
|
+ dat_entry = kmalloc(sizeof(*dat_entry), GFP_ATOMIC);
|
|
|
+ if (!dat_entry)
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ dat_entry->ip = ip;
|
|
|
+ memcpy(dat_entry->mac_addr, mac_addr, ETH_ALEN);
|
|
|
+ dat_entry->last_update = jiffies;
|
|
|
+ atomic_set(&dat_entry->refcount, 2);
|
|
|
+
|
|
|
+ hash_added = batadv_hash_add(bat_priv->dat.hash, batadv_compare_dat,
|
|
|
+ batadv_hash_dat, &dat_entry->ip,
|
|
|
+ &dat_entry->hash_entry);
|
|
|
+
|
|
|
+ if (unlikely(hash_added != 0)) {
|
|
|
+ /* remove the reference for the hash */
|
|
|
+ batadv_dat_entry_free_ref(dat_entry);
|
|
|
+ goto out;
|
|
|
+ }
|
|
|
+
|
|
|
+ batadv_dbg(BATADV_DBG_DAT, bat_priv, "New entry added: %pI4 %pM\n",
|
|
|
+ &dat_entry->ip, dat_entry->mac_addr);
|
|
|
+
|
|
|
+out:
|
|
|
+ if (dat_entry)
|
|
|
+ batadv_dat_entry_free_ref(dat_entry);
|
|
|
+}
|
|
|
+
|
|
|
+#ifdef CONFIG_BATMAN_ADV_DEBUG
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_dbg_arp - print a debug message containing all the ARP packet details
|
|
|
+ * @bat_priv: the bat priv with all the soft interface information
|
|
|
+ * @skb: ARP packet
|
|
|
+ * @type: ARP type
|
|
|
+ * @hdr_size: size of the possible header before the ARP packet
|
|
|
+ * @msg: message to print together with the debugging information
|
|
|
+ */
|
|
|
+static void batadv_dbg_arp(struct batadv_priv *bat_priv, struct sk_buff *skb,
|
|
|
+ uint16_t type, int hdr_size, char *msg)
|
|
|
+{
|
|
|
+ struct batadv_unicast_4addr_packet *unicast_4addr_packet;
|
|
|
+ struct batadv_bcast_packet *bcast_pkt;
|
|
|
+ uint8_t *orig_addr;
|
|
|
+ __be32 ip_src, ip_dst;
|
|
|
+
|
|
|
+ if (msg)
|
|
|
+ batadv_dbg(BATADV_DBG_DAT, bat_priv, "%s\n", msg);
|
|
|
+
|
|
|
+ ip_src = batadv_arp_ip_src(skb, hdr_size);
|
|
|
+ ip_dst = batadv_arp_ip_dst(skb, hdr_size);
|
|
|
+ batadv_dbg(BATADV_DBG_DAT, bat_priv,
|
|
|
+ "ARP MSG = [src: %pM-%pI4 dst: %pM-%pI4]\n",
|
|
|
+ batadv_arp_hw_src(skb, hdr_size), &ip_src,
|
|
|
+ batadv_arp_hw_dst(skb, hdr_size), &ip_dst);
|
|
|
+
|
|
|
+ if (hdr_size == 0)
|
|
|
+ return;
|
|
|
+
|
|
|
+ /* if the ARP packet is encapsulated in a batman packet, let's print
|
|
|
+ * some debug messages
|
|
|
+ */
|
|
|
+ unicast_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data;
|
|
|
+
|
|
|
+ switch (unicast_4addr_packet->u.header.packet_type) {
|
|
|
+ case BATADV_UNICAST:
|
|
|
+ batadv_dbg(BATADV_DBG_DAT, bat_priv,
|
|
|
+ "* encapsulated within a UNICAST packet\n");
|
|
|
+ break;
|
|
|
+ case BATADV_UNICAST_4ADDR:
|
|
|
+ batadv_dbg(BATADV_DBG_DAT, bat_priv,
|
|
|
+ "* encapsulated within a UNICAST_4ADDR packet (src: %pM)\n",
|
|
|
+ unicast_4addr_packet->src);
|
|
|
+ switch (unicast_4addr_packet->subtype) {
|
|
|
+ case BATADV_P_DAT_DHT_PUT:
|
|
|
+ batadv_dbg(BATADV_DBG_DAT, bat_priv, "* type: DAT_DHT_PUT\n");
|
|
|
+ break;
|
|
|
+ case BATADV_P_DAT_DHT_GET:
|
|
|
+ batadv_dbg(BATADV_DBG_DAT, bat_priv, "* type: DAT_DHT_GET\n");
|
|
|
+ break;
|
|
|
+ case BATADV_P_DAT_CACHE_REPLY:
|
|
|
+ batadv_dbg(BATADV_DBG_DAT, bat_priv,
|
|
|
+ "* type: DAT_CACHE_REPLY\n");
|
|
|
+ break;
|
|
|
+ case BATADV_P_DATA:
|
|
|
+ batadv_dbg(BATADV_DBG_DAT, bat_priv, "* type: DATA\n");
|
|
|
+ break;
|
|
|
+ default:
|
|
|
+ batadv_dbg(BATADV_DBG_DAT, bat_priv, "* type: Unknown (%u)!\n",
|
|
|
+ unicast_4addr_packet->u.header.packet_type);
|
|
|
+ }
|
|
|
+ break;
|
|
|
+ case BATADV_BCAST:
|
|
|
+ bcast_pkt = (struct batadv_bcast_packet *)unicast_4addr_packet;
|
|
|
+ orig_addr = bcast_pkt->orig;
|
|
|
+ batadv_dbg(BATADV_DBG_DAT, bat_priv,
|
|
|
+ "* encapsulated within a BCAST packet (src: %pM)\n",
|
|
|
+ orig_addr);
|
|
|
+ break;
|
|
|
+ default:
|
|
|
+ batadv_dbg(BATADV_DBG_DAT, bat_priv,
|
|
|
+ "* encapsulated within an unknown packet type (0x%x)\n",
|
|
|
+ unicast_4addr_packet->u.header.packet_type);
|
|
|
+ }
|
|
|
+}
|
|
|
+
|
|
|
+#else
|
|
|
+
|
|
|
+static void batadv_dbg_arp(struct batadv_priv *bat_priv, struct sk_buff *skb,
|
|
|
+ uint16_t type, int hdr_size, char *msg)
|
|
|
+{
|
|
|
+}
|
|
|
+
|
|
|
+#endif /* CONFIG_BATMAN_ADV_DEBUG */
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_is_orig_node_eligible - check whether a node can be a DHT candidate
|
|
|
+ * @res: the array with the already selected candidates
|
|
|
+ * @select: number of already selected candidates
|
|
|
+ * @tmp_max: address of the currently evaluated node
|
|
|
+ * @max: current round max address
|
|
|
+ * @last_max: address of the last selected candidate
|
|
|
+ * @candidate: orig_node under evaluation
|
|
|
+ * @max_orig_node: last selected candidate
|
|
|
+ *
|
|
|
+ * Returns true if the node has been elected as next candidate or false othrwise
|
|
|
+ */
|
|
|
+static bool batadv_is_orig_node_eligible(struct batadv_dat_candidate *res,
|
|
|
+ int select, batadv_dat_addr_t tmp_max,
|
|
|
+ batadv_dat_addr_t max,
|
|
|
+ batadv_dat_addr_t last_max,
|
|
|
+ struct batadv_orig_node *candidate,
|
|
|
+ struct batadv_orig_node *max_orig_node)
|
|
|
+{
|
|
|
+ bool ret = false;
|
|
|
+ int j;
|
|
|
+
|
|
|
+ /* Check if this node has already been selected... */
|
|
|
+ for (j = 0; j < select; j++)
|
|
|
+ if (res[j].orig_node == candidate)
|
|
|
+ break;
|
|
|
+ /* ..and possibly skip it */
|
|
|
+ if (j < select)
|
|
|
+ goto out;
|
|
|
+ /* sanity check: has it already been selected? This should not happen */
|
|
|
+ if (tmp_max > last_max)
|
|
|
+ goto out;
|
|
|
+ /* check if during this iteration an originator with a closer dht
|
|
|
+ * address has already been found
|
|
|
+ */
|
|
|
+ if (tmp_max < max)
|
|
|
+ goto out;
|
|
|
+ /* this is an hash collision with the temporary selected node. Choose
|
|
|
+ * the one with the lowest address
|
|
|
+ */
|
|
|
+ if ((tmp_max == max) &&
|
|
|
+ (batadv_compare_eth(candidate->orig, max_orig_node->orig) > 0))
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ ret = true;
|
|
|
+out:
|
|
|
+ return ret;
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_choose_next_candidate - select the next DHT candidate
|
|
|
+ * @bat_priv: the bat priv with all the soft interface information
|
|
|
+ * @cands: candidates array
|
|
|
+ * @select: number of candidates already present in the array
|
|
|
+ * @ip_key: key to look up in the DHT
|
|
|
+ * @last_max: pointer where the address of the selected candidate will be saved
|
|
|
+ */
|
|
|
+static void batadv_choose_next_candidate(struct batadv_priv *bat_priv,
|
|
|
+ struct batadv_dat_candidate *cands,
|
|
|
+ int select, batadv_dat_addr_t ip_key,
|
|
|
+ batadv_dat_addr_t *last_max)
|
|
|
+{
|
|
|
+ batadv_dat_addr_t max = 0, tmp_max = 0;
|
|
|
+ struct batadv_orig_node *orig_node, *max_orig_node = NULL;
|
|
|
+ struct batadv_hashtable *hash = bat_priv->orig_hash;
|
|
|
+ struct hlist_node *node;
|
|
|
+ struct hlist_head *head;
|
|
|
+ int i;
|
|
|
+
|
|
|
+ /* if no node is eligible as candidate, leave the candidate type as
|
|
|
+ * NOT_FOUND
|
|
|
+ */
|
|
|
+ cands[select].type = BATADV_DAT_CANDIDATE_NOT_FOUND;
|
|
|
+
|
|
|
+ /* iterate over the originator list and find the node with closest
|
|
|
+ * dat_address which has not been selected yet
|
|
|
+ */
|
|
|
+ for (i = 0; i < hash->size; i++) {
|
|
|
+ head = &hash->table[i];
|
|
|
+
|
|
|
+ rcu_read_lock();
|
|
|
+ hlist_for_each_entry_rcu(orig_node, node, head, hash_entry) {
|
|
|
+ /* the dht space is a ring and addresses are unsigned */
|
|
|
+ tmp_max = BATADV_DAT_ADDR_MAX - orig_node->dat_addr +
|
|
|
+ ip_key;
|
|
|
+
|
|
|
+ if (!batadv_is_orig_node_eligible(cands, select,
|
|
|
+ tmp_max, max,
|
|
|
+ *last_max, orig_node,
|
|
|
+ max_orig_node))
|
|
|
+ continue;
|
|
|
+
|
|
|
+ if (!atomic_inc_not_zero(&orig_node->refcount))
|
|
|
+ continue;
|
|
|
+
|
|
|
+ max = tmp_max;
|
|
|
+ if (max_orig_node)
|
|
|
+ batadv_orig_node_free_ref(max_orig_node);
|
|
|
+ max_orig_node = orig_node;
|
|
|
+ }
|
|
|
+ rcu_read_unlock();
|
|
|
+ }
|
|
|
+ if (max_orig_node) {
|
|
|
+ cands[select].type = BATADV_DAT_CANDIDATE_ORIG;
|
|
|
+ cands[select].orig_node = max_orig_node;
|
|
|
+ batadv_dbg(BATADV_DBG_DAT, bat_priv,
|
|
|
+ "dat_select_candidates() %d: selected %pM addr=%u dist=%u\n",
|
|
|
+ select, max_orig_node->orig, max_orig_node->dat_addr,
|
|
|
+ max);
|
|
|
+ }
|
|
|
+ *last_max = max;
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_dat_select_candidates - selects the nodes which the DHT message has to
|
|
|
+ * be sent to
|
|
|
+ * @bat_priv: the bat priv with all the soft interface information
|
|
|
+ * @ip_dst: ipv4 to look up in the DHT
|
|
|
+ *
|
|
|
+ * An originator O is selected if and only if its DHT_ID value is one of three
|
|
|
+ * closest values (from the LEFT, with wrap around if needed) then the hash
|
|
|
+ * value of the key. ip_dst is the key.
|
|
|
+ *
|
|
|
+ * Returns the candidate array of size BATADV_DAT_CANDIDATE_NUM
|
|
|
+ */
|
|
|
+static struct batadv_dat_candidate *
|
|
|
+batadv_dat_select_candidates(struct batadv_priv *bat_priv, __be32 ip_dst)
|
|
|
+{
|
|
|
+ int select;
|
|
|
+ batadv_dat_addr_t last_max = BATADV_DAT_ADDR_MAX, ip_key;
|
|
|
+ struct batadv_dat_candidate *res;
|
|
|
+
|
|
|
+ if (!bat_priv->orig_hash)
|
|
|
+ return NULL;
|
|
|
+
|
|
|
+ res = kmalloc(BATADV_DAT_CANDIDATES_NUM * sizeof(*res), GFP_ATOMIC);
|
|
|
+ if (!res)
|
|
|
+ return NULL;
|
|
|
+
|
|
|
+ ip_key = (batadv_dat_addr_t)batadv_hash_dat(&ip_dst,
|
|
|
+ BATADV_DAT_ADDR_MAX);
|
|
|
+
|
|
|
+ batadv_dbg(BATADV_DBG_DAT, bat_priv,
|
|
|
+ "dat_select_candidates(): IP=%pI4 hash(IP)=%u\n", &ip_dst,
|
|
|
+ ip_key);
|
|
|
+
|
|
|
+ for (select = 0; select < BATADV_DAT_CANDIDATES_NUM; select++)
|
|
|
+ batadv_choose_next_candidate(bat_priv, res, select, ip_key,
|
|
|
+ &last_max);
|
|
|
+
|
|
|
+ return res;
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_dat_send_data - send a payload to the selected candidates
|
|
|
+ * @bat_priv: the bat priv with all the soft interface information
|
|
|
+ * @skb: payload to send
|
|
|
+ * @ip: the DHT key
|
|
|
+ * @packet_subtype: unicast4addr packet subtype to use
|
|
|
+ *
|
|
|
+ * In this function the skb is copied by means of pskb_copy() and is sent as
|
|
|
+ * unicast packet to each of the selected candidates
|
|
|
+ *
|
|
|
+ * Returns true if the packet is sent to at least one candidate, false otherwise
|
|
|
+ */
|
|
|
+static bool batadv_dat_send_data(struct batadv_priv *bat_priv,
|
|
|
+ struct sk_buff *skb, __be32 ip,
|
|
|
+ int packet_subtype)
|
|
|
+{
|
|
|
+ int i;
|
|
|
+ bool ret = false;
|
|
|
+ int send_status;
|
|
|
+ struct batadv_neigh_node *neigh_node = NULL;
|
|
|
+ struct sk_buff *tmp_skb;
|
|
|
+ struct batadv_dat_candidate *cand;
|
|
|
+
|
|
|
+ cand = batadv_dat_select_candidates(bat_priv, ip);
|
|
|
+ if (!cand)
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ batadv_dbg(BATADV_DBG_DAT, bat_priv, "DHT_SEND for %pI4\n", &ip);
|
|
|
+
|
|
|
+ for (i = 0; i < BATADV_DAT_CANDIDATES_NUM; i++) {
|
|
|
+ if (cand[i].type == BATADV_DAT_CANDIDATE_NOT_FOUND)
|
|
|
+ continue;
|
|
|
+
|
|
|
+ neigh_node = batadv_orig_node_get_router(cand[i].orig_node);
|
|
|
+ if (!neigh_node)
|
|
|
+ goto free_orig;
|
|
|
+
|
|
|
+ tmp_skb = pskb_copy(skb, GFP_ATOMIC);
|
|
|
+ if (!batadv_unicast_4addr_prepare_skb(bat_priv, tmp_skb,
|
|
|
+ cand[i].orig_node,
|
|
|
+ packet_subtype)) {
|
|
|
+ kfree_skb(tmp_skb);
|
|
|
+ goto free_neigh;
|
|
|
+ }
|
|
|
+
|
|
|
+ send_status = batadv_send_skb_packet(tmp_skb,
|
|
|
+ neigh_node->if_incoming,
|
|
|
+ neigh_node->addr);
|
|
|
+ if (send_status == NET_XMIT_SUCCESS) {
|
|
|
+ /* count the sent packet */
|
|
|
+ switch (packet_subtype) {
|
|
|
+ case BATADV_P_DAT_DHT_GET:
|
|
|
+ batadv_inc_counter(bat_priv,
|
|
|
+ BATADV_CNT_DAT_GET_TX);
|
|
|
+ break;
|
|
|
+ case BATADV_P_DAT_DHT_PUT:
|
|
|
+ batadv_inc_counter(bat_priv,
|
|
|
+ BATADV_CNT_DAT_PUT_TX);
|
|
|
+ break;
|
|
|
+ }
|
|
|
+
|
|
|
+ /* packet sent to a candidate: return true */
|
|
|
+ ret = true;
|
|
|
+ }
|
|
|
+free_neigh:
|
|
|
+ batadv_neigh_node_free_ref(neigh_node);
|
|
|
+free_orig:
|
|
|
+ batadv_orig_node_free_ref(cand[i].orig_node);
|
|
|
+ }
|
|
|
+
|
|
|
+out:
|
|
|
+ kfree(cand);
|
|
|
+ return ret;
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_dat_hash_free - free the local DAT hash table
|
|
|
+ * @bat_priv: the bat priv with all the soft interface information
|
|
|
+ */
|
|
|
+static void batadv_dat_hash_free(struct batadv_priv *bat_priv)
|
|
|
+{
|
|
|
+ if (!bat_priv->dat.hash)
|
|
|
+ return;
|
|
|
+
|
|
|
+ __batadv_dat_purge(bat_priv, NULL);
|
|
|
+
|
|
|
+ batadv_hash_destroy(bat_priv->dat.hash);
|
|
|
+
|
|
|
+ bat_priv->dat.hash = NULL;
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_dat_init - initialise the DAT internals
|
|
|
+ * @bat_priv: the bat priv with all the soft interface information
|
|
|
+ */
|
|
|
+int batadv_dat_init(struct batadv_priv *bat_priv)
|
|
|
+{
|
|
|
+ if (bat_priv->dat.hash)
|
|
|
+ return 0;
|
|
|
+
|
|
|
+ bat_priv->dat.hash = batadv_hash_new(1024);
|
|
|
+
|
|
|
+ if (!bat_priv->dat.hash)
|
|
|
+ return -ENOMEM;
|
|
|
+
|
|
|
+ batadv_dat_start_timer(bat_priv);
|
|
|
+
|
|
|
+ return 0;
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_dat_free - free the DAT internals
|
|
|
+ * @bat_priv: the bat priv with all the soft interface information
|
|
|
+ */
|
|
|
+void batadv_dat_free(struct batadv_priv *bat_priv)
|
|
|
+{
|
|
|
+ cancel_delayed_work_sync(&bat_priv->dat.work);
|
|
|
+
|
|
|
+ batadv_dat_hash_free(bat_priv);
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_dat_cache_seq_print_text - print the local DAT hash table
|
|
|
+ * @seq: seq file to print on
|
|
|
+ * @offset: not used
|
|
|
+ */
|
|
|
+int batadv_dat_cache_seq_print_text(struct seq_file *seq, void *offset)
|
|
|
+{
|
|
|
+ struct net_device *net_dev = (struct net_device *)seq->private;
|
|
|
+ struct batadv_priv *bat_priv = netdev_priv(net_dev);
|
|
|
+ struct batadv_hashtable *hash = bat_priv->dat.hash;
|
|
|
+ struct batadv_dat_entry *dat_entry;
|
|
|
+ struct batadv_hard_iface *primary_if;
|
|
|
+ struct hlist_node *node;
|
|
|
+ struct hlist_head *head;
|
|
|
+ unsigned long last_seen_jiffies;
|
|
|
+ int last_seen_msecs, last_seen_secs, last_seen_mins;
|
|
|
+ uint32_t i;
|
|
|
+
|
|
|
+ primary_if = batadv_seq_print_text_primary_if_get(seq);
|
|
|
+ if (!primary_if)
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ seq_printf(seq, "Distributed ARP Table (%s):\n", net_dev->name);
|
|
|
+ seq_printf(seq, " %-7s %-13s %5s\n", "IPv4", "MAC",
|
|
|
+ "last-seen");
|
|
|
+
|
|
|
+ for (i = 0; i < hash->size; i++) {
|
|
|
+ head = &hash->table[i];
|
|
|
+
|
|
|
+ rcu_read_lock();
|
|
|
+ hlist_for_each_entry_rcu(dat_entry, node, head, hash_entry) {
|
|
|
+ last_seen_jiffies = jiffies - dat_entry->last_update;
|
|
|
+ last_seen_msecs = jiffies_to_msecs(last_seen_jiffies);
|
|
|
+ last_seen_mins = last_seen_msecs / 60000;
|
|
|
+ last_seen_msecs = last_seen_msecs % 60000;
|
|
|
+ last_seen_secs = last_seen_msecs / 1000;
|
|
|
+
|
|
|
+ seq_printf(seq, " * %15pI4 %14pM %6i:%02i\n",
|
|
|
+ &dat_entry->ip, dat_entry->mac_addr,
|
|
|
+ last_seen_mins, last_seen_secs);
|
|
|
+ }
|
|
|
+ rcu_read_unlock();
|
|
|
+ }
|
|
|
+
|
|
|
+out:
|
|
|
+ if (primary_if)
|
|
|
+ batadv_hardif_free_ref(primary_if);
|
|
|
+ return 0;
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_arp_get_type - parse an ARP packet and gets the type
|
|
|
+ * @bat_priv: the bat priv with all the soft interface information
|
|
|
+ * @skb: packet to analyse
|
|
|
+ * @hdr_size: size of the possible header before the ARP packet in the skb
|
|
|
+ *
|
|
|
+ * Returns the ARP type if the skb contains a valid ARP packet, 0 otherwise
|
|
|
+ */
|
|
|
+static uint16_t batadv_arp_get_type(struct batadv_priv *bat_priv,
|
|
|
+ struct sk_buff *skb, int hdr_size)
|
|
|
+{
|
|
|
+ struct arphdr *arphdr;
|
|
|
+ struct ethhdr *ethhdr;
|
|
|
+ __be32 ip_src, ip_dst;
|
|
|
+ uint16_t type = 0;
|
|
|
+
|
|
|
+ /* pull the ethernet header */
|
|
|
+ if (unlikely(!pskb_may_pull(skb, hdr_size + ETH_HLEN)))
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ ethhdr = (struct ethhdr *)(skb->data + hdr_size);
|
|
|
+
|
|
|
+ if (ethhdr->h_proto != htons(ETH_P_ARP))
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ /* pull the ARP payload */
|
|
|
+ if (unlikely(!pskb_may_pull(skb, hdr_size + ETH_HLEN +
|
|
|
+ arp_hdr_len(skb->dev))))
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ arphdr = (struct arphdr *)(skb->data + hdr_size + ETH_HLEN);
|
|
|
+
|
|
|
+ /* Check whether the ARP packet carries a valid
|
|
|
+ * IP information
|
|
|
+ */
|
|
|
+ if (arphdr->ar_hrd != htons(ARPHRD_ETHER))
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ if (arphdr->ar_pro != htons(ETH_P_IP))
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ if (arphdr->ar_hln != ETH_ALEN)
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ if (arphdr->ar_pln != 4)
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ /* Check for bad reply/request. If the ARP message is not sane, DAT
|
|
|
+ * will simply ignore it
|
|
|
+ */
|
|
|
+ ip_src = batadv_arp_ip_src(skb, hdr_size);
|
|
|
+ ip_dst = batadv_arp_ip_dst(skb, hdr_size);
|
|
|
+ if (ipv4_is_loopback(ip_src) || ipv4_is_multicast(ip_src) ||
|
|
|
+ ipv4_is_loopback(ip_dst) || ipv4_is_multicast(ip_dst))
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ type = ntohs(arphdr->ar_op);
|
|
|
+out:
|
|
|
+ return type;
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_dat_snoop_outgoing_arp_request - snoop the ARP request and try to
|
|
|
+ * answer using DAT
|
|
|
+ * @bat_priv: the bat priv with all the soft interface information
|
|
|
+ * @skb: packet to check
|
|
|
+ *
|
|
|
+ * Returns true if the message has been sent to the dht candidates, false
|
|
|
+ * otherwise. In case of true the message has to be enqueued to permit the
|
|
|
+ * fallback
|
|
|
+ */
|
|
|
+bool batadv_dat_snoop_outgoing_arp_request(struct batadv_priv *bat_priv,
|
|
|
+ struct sk_buff *skb)
|
|
|
+{
|
|
|
+ uint16_t type = 0;
|
|
|
+ __be32 ip_dst, ip_src;
|
|
|
+ uint8_t *hw_src;
|
|
|
+ bool ret = false;
|
|
|
+ struct batadv_dat_entry *dat_entry = NULL;
|
|
|
+ struct sk_buff *skb_new;
|
|
|
+ struct batadv_hard_iface *primary_if = NULL;
|
|
|
+
|
|
|
+ if (!atomic_read(&bat_priv->distributed_arp_table))
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ type = batadv_arp_get_type(bat_priv, skb, 0);
|
|
|
+ /* If the node gets an ARP_REQUEST it has to send a DHT_GET unicast
|
|
|
+ * message to the selected DHT candidates
|
|
|
+ */
|
|
|
+ if (type != ARPOP_REQUEST)
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ batadv_dbg_arp(bat_priv, skb, type, 0, "Parsing outgoing ARP REQUEST");
|
|
|
+
|
|
|
+ ip_src = batadv_arp_ip_src(skb, 0);
|
|
|
+ hw_src = batadv_arp_hw_src(skb, 0);
|
|
|
+ ip_dst = batadv_arp_ip_dst(skb, 0);
|
|
|
+
|
|
|
+ batadv_dat_entry_add(bat_priv, ip_src, hw_src);
|
|
|
+
|
|
|
+ dat_entry = batadv_dat_entry_hash_find(bat_priv, ip_dst);
|
|
|
+ if (dat_entry) {
|
|
|
+ primary_if = batadv_primary_if_get_selected(bat_priv);
|
|
|
+ if (!primary_if)
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ skb_new = arp_create(ARPOP_REPLY, ETH_P_ARP, ip_src,
|
|
|
+ primary_if->soft_iface, ip_dst, hw_src,
|
|
|
+ dat_entry->mac_addr, hw_src);
|
|
|
+ if (!skb_new)
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ skb_reset_mac_header(skb_new);
|
|
|
+ skb_new->protocol = eth_type_trans(skb_new,
|
|
|
+ primary_if->soft_iface);
|
|
|
+ bat_priv->stats.rx_packets++;
|
|
|
+ bat_priv->stats.rx_bytes += skb->len + ETH_HLEN;
|
|
|
+ primary_if->soft_iface->last_rx = jiffies;
|
|
|
+
|
|
|
+ netif_rx(skb_new);
|
|
|
+ batadv_dbg(BATADV_DBG_DAT, bat_priv, "ARP request replied locally\n");
|
|
|
+ ret = true;
|
|
|
+ } else {
|
|
|
+ /* Send the request on the DHT */
|
|
|
+ ret = batadv_dat_send_data(bat_priv, skb, ip_dst,
|
|
|
+ BATADV_P_DAT_DHT_GET);
|
|
|
+ }
|
|
|
+out:
|
|
|
+ if (dat_entry)
|
|
|
+ batadv_dat_entry_free_ref(dat_entry);
|
|
|
+ if (primary_if)
|
|
|
+ batadv_hardif_free_ref(primary_if);
|
|
|
+ return ret;
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_dat_snoop_incoming_arp_request - snoop the ARP request and try to
|
|
|
+ * answer using the local DAT storage
|
|
|
+ * @bat_priv: the bat priv with all the soft interface information
|
|
|
+ * @skb: packet to check
|
|
|
+ * @hdr_size: size of the encapsulation header
|
|
|
+ *
|
|
|
+ * Returns true if the request has been answered, false otherwise
|
|
|
+ */
|
|
|
+bool batadv_dat_snoop_incoming_arp_request(struct batadv_priv *bat_priv,
|
|
|
+ struct sk_buff *skb, int hdr_size)
|
|
|
+{
|
|
|
+ uint16_t type;
|
|
|
+ __be32 ip_src, ip_dst;
|
|
|
+ uint8_t *hw_src;
|
|
|
+ struct sk_buff *skb_new;
|
|
|
+ struct batadv_hard_iface *primary_if = NULL;
|
|
|
+ struct batadv_dat_entry *dat_entry = NULL;
|
|
|
+ bool ret = false;
|
|
|
+ int err;
|
|
|
+
|
|
|
+ if (!atomic_read(&bat_priv->distributed_arp_table))
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ type = batadv_arp_get_type(bat_priv, skb, hdr_size);
|
|
|
+ if (type != ARPOP_REQUEST)
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ hw_src = batadv_arp_hw_src(skb, hdr_size);
|
|
|
+ ip_src = batadv_arp_ip_src(skb, hdr_size);
|
|
|
+ ip_dst = batadv_arp_ip_dst(skb, hdr_size);
|
|
|
+
|
|
|
+ batadv_dbg_arp(bat_priv, skb, type, hdr_size,
|
|
|
+ "Parsing incoming ARP REQUEST");
|
|
|
+
|
|
|
+ batadv_dat_entry_add(bat_priv, ip_src, hw_src);
|
|
|
+
|
|
|
+ dat_entry = batadv_dat_entry_hash_find(bat_priv, ip_dst);
|
|
|
+ if (!dat_entry)
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ primary_if = batadv_primary_if_get_selected(bat_priv);
|
|
|
+ if (!primary_if)
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ skb_new = arp_create(ARPOP_REPLY, ETH_P_ARP, ip_src,
|
|
|
+ primary_if->soft_iface, ip_dst, hw_src,
|
|
|
+ dat_entry->mac_addr, hw_src);
|
|
|
+
|
|
|
+ if (!skb_new)
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ /* to preserve backwards compatibility, here the node has to answer
|
|
|
+ * using the same packet type it received for the request. This is due
|
|
|
+ * to that if a node is not using the 4addr packet format it may not
|
|
|
+ * support it.
|
|
|
+ */
|
|
|
+ if (hdr_size == sizeof(struct batadv_unicast_4addr_packet))
|
|
|
+ err = batadv_unicast_4addr_send_skb(bat_priv, skb_new,
|
|
|
+ BATADV_P_DAT_CACHE_REPLY);
|
|
|
+ else
|
|
|
+ err = batadv_unicast_send_skb(bat_priv, skb_new);
|
|
|
+
|
|
|
+ if (!err) {
|
|
|
+ batadv_inc_counter(bat_priv, BATADV_CNT_DAT_CACHED_REPLY_TX);
|
|
|
+ ret = true;
|
|
|
+ }
|
|
|
+out:
|
|
|
+ if (dat_entry)
|
|
|
+ batadv_dat_entry_free_ref(dat_entry);
|
|
|
+ if (primary_if)
|
|
|
+ batadv_hardif_free_ref(primary_if);
|
|
|
+ if (ret)
|
|
|
+ kfree_skb(skb);
|
|
|
+ return ret;
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_dat_snoop_outgoing_arp_reply - snoop the ARP reply and fill the DHT
|
|
|
+ * @bat_priv: the bat priv with all the soft interface information
|
|
|
+ * @skb: packet to check
|
|
|
+ */
|
|
|
+void batadv_dat_snoop_outgoing_arp_reply(struct batadv_priv *bat_priv,
|
|
|
+ struct sk_buff *skb)
|
|
|
+{
|
|
|
+ uint16_t type;
|
|
|
+ __be32 ip_src, ip_dst;
|
|
|
+ uint8_t *hw_src, *hw_dst;
|
|
|
+
|
|
|
+ if (!atomic_read(&bat_priv->distributed_arp_table))
|
|
|
+ return;
|
|
|
+
|
|
|
+ type = batadv_arp_get_type(bat_priv, skb, 0);
|
|
|
+ if (type != ARPOP_REPLY)
|
|
|
+ return;
|
|
|
+
|
|
|
+ batadv_dbg_arp(bat_priv, skb, type, 0, "Parsing outgoing ARP REPLY");
|
|
|
+
|
|
|
+ hw_src = batadv_arp_hw_src(skb, 0);
|
|
|
+ ip_src = batadv_arp_ip_src(skb, 0);
|
|
|
+ hw_dst = batadv_arp_hw_dst(skb, 0);
|
|
|
+ ip_dst = batadv_arp_ip_dst(skb, 0);
|
|
|
+
|
|
|
+ batadv_dat_entry_add(bat_priv, ip_src, hw_src);
|
|
|
+ batadv_dat_entry_add(bat_priv, ip_dst, hw_dst);
|
|
|
+
|
|
|
+ /* Send the ARP reply to the candidates for both the IP addresses that
|
|
|
+ * the node got within the ARP reply
|
|
|
+ */
|
|
|
+ batadv_dat_send_data(bat_priv, skb, ip_src, BATADV_P_DAT_DHT_PUT);
|
|
|
+ batadv_dat_send_data(bat_priv, skb, ip_dst, BATADV_P_DAT_DHT_PUT);
|
|
|
+}
|
|
|
+/**
|
|
|
+ * batadv_dat_snoop_incoming_arp_reply - snoop the ARP reply and fill the local
|
|
|
+ * DAT storage only
|
|
|
+ * @bat_priv: the bat priv with all the soft interface information
|
|
|
+ * @skb: packet to check
|
|
|
+ * @hdr_size: siaze of the encapsulation header
|
|
|
+ */
|
|
|
+bool batadv_dat_snoop_incoming_arp_reply(struct batadv_priv *bat_priv,
|
|
|
+ struct sk_buff *skb, int hdr_size)
|
|
|
+{
|
|
|
+ uint16_t type;
|
|
|
+ __be32 ip_src, ip_dst;
|
|
|
+ uint8_t *hw_src, *hw_dst;
|
|
|
+ bool ret = false;
|
|
|
+
|
|
|
+ if (!atomic_read(&bat_priv->distributed_arp_table))
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ type = batadv_arp_get_type(bat_priv, skb, hdr_size);
|
|
|
+ if (type != ARPOP_REPLY)
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ batadv_dbg_arp(bat_priv, skb, type, hdr_size,
|
|
|
+ "Parsing incoming ARP REPLY");
|
|
|
+
|
|
|
+ hw_src = batadv_arp_hw_src(skb, hdr_size);
|
|
|
+ ip_src = batadv_arp_ip_src(skb, hdr_size);
|
|
|
+ hw_dst = batadv_arp_hw_dst(skb, hdr_size);
|
|
|
+ ip_dst = batadv_arp_ip_dst(skb, hdr_size);
|
|
|
+
|
|
|
+ /* Update our internal cache with both the IP addresses the node got
|
|
|
+ * within the ARP reply
|
|
|
+ */
|
|
|
+ batadv_dat_entry_add(bat_priv, ip_src, hw_src);
|
|
|
+ batadv_dat_entry_add(bat_priv, ip_dst, hw_dst);
|
|
|
+
|
|
|
+ /* if this REPLY is directed to a client of mine, let's deliver the
|
|
|
+ * packet to the interface
|
|
|
+ */
|
|
|
+ ret = !batadv_is_my_client(bat_priv, hw_dst);
|
|
|
+out:
|
|
|
+ /* if ret == false -> packet has to be delivered to the interface */
|
|
|
+ return ret;
|
|
|
+}
|
|
|
+
|
|
|
+/**
|
|
|
+ * batadv_dat_drop_broadcast_packet - check if an ARP request has to be dropped
|
|
|
+ * (because the node has already got the reply via DAT) or not
|
|
|
+ * @bat_priv: the bat priv with all the soft interface information
|
|
|
+ * @forw_packet: the broadcast packet
|
|
|
+ *
|
|
|
+ * Returns true if the node can drop the packet, false otherwise
|
|
|
+ */
|
|
|
+bool batadv_dat_drop_broadcast_packet(struct batadv_priv *bat_priv,
|
|
|
+ struct batadv_forw_packet *forw_packet)
|
|
|
+{
|
|
|
+ uint16_t type;
|
|
|
+ __be32 ip_dst;
|
|
|
+ struct batadv_dat_entry *dat_entry = NULL;
|
|
|
+ bool ret = false;
|
|
|
+ const size_t bcast_len = sizeof(struct batadv_bcast_packet);
|
|
|
+
|
|
|
+ if (!atomic_read(&bat_priv->distributed_arp_table))
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ /* If this packet is an ARP_REQUEST and the node already has the
|
|
|
+ * information that it is going to ask, then the packet can be dropped
|
|
|
+ */
|
|
|
+ if (forw_packet->num_packets)
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ type = batadv_arp_get_type(bat_priv, forw_packet->skb, bcast_len);
|
|
|
+ if (type != ARPOP_REQUEST)
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ ip_dst = batadv_arp_ip_dst(forw_packet->skb, bcast_len);
|
|
|
+ dat_entry = batadv_dat_entry_hash_find(bat_priv, ip_dst);
|
|
|
+ /* check if the node already got this entry */
|
|
|
+ if (!dat_entry) {
|
|
|
+ batadv_dbg(BATADV_DBG_DAT, bat_priv,
|
|
|
+ "ARP Request for %pI4: fallback\n", &ip_dst);
|
|
|
+ goto out;
|
|
|
+ }
|
|
|
+
|
|
|
+ batadv_dbg(BATADV_DBG_DAT, bat_priv,
|
|
|
+ "ARP Request for %pI4: fallback prevented\n", &ip_dst);
|
|
|
+ ret = true;
|
|
|
+
|
|
|
+out:
|
|
|
+ if (dat_entry)
|
|
|
+ batadv_dat_entry_free_ref(dat_entry);
|
|
|
+ return ret;
|
|
|
+}
|
David S. Miller