Merge tag 'batman-adv-for-davem' of git://git.open-mesh.org/linux-merge

batman-adv-$(CONFIG_BATMAN_ADV_BLA) += bridge_loop_avoidance.o

batman-adv-y += debugfs.o

batman-adv-$(CONFIG_BATMAN_ADV_DAT) += distributed-arp-table.o

batman-adv-y += fragmentation.o

batman-adv-y += gateway_client.o

batman-adv-y += gateway_common.o

batman-adv-y += hard-interface.o

batman-adv-y += soft-interface.o

batman-adv-y += sysfs.o

batman-adv-y += translation-table.o

batman-adv-y += unicast.o

	struct arphdr *arphdr;

	uint8_t *hw_src, *hw_dst;

	struct batadv_bla_claim_dst *bla_dst;

	uint16_t proto;

	__be16 proto;

	int headlen;

	unsigned short vid = BATADV_NO_FLAGS;

	int ret;

	ethhdr = eth_hdr(skb);

	if (ntohs(ethhdr->h_proto) == ETH_P_8021Q) {

	if (ethhdr->h_proto == htons(ETH_P_8021Q)) {

		vhdr = (struct vlan_ethhdr *)ethhdr;

		vid = ntohs(vhdr->h_vlan_TCI) & VLAN_VID_MASK;

		vid |= BATADV_VLAN_HAS_TAG;

		proto = ntohs(vhdr->h_vlan_encapsulated_proto);

		proto = vhdr->h_vlan_encapsulated_proto;

		headlen = sizeof(*vhdr);

	} else {

		proto = ntohs(ethhdr->h_proto);

		proto = ethhdr->h_proto;

		headlen = ETH_HLEN;

	}

	if (proto != ETH_P_ARP)

	if (proto != htons(ETH_P_ARP))

		return 0; /* not a claim frame */

	/* this must be a ARP frame. check if it is a claim. */

	ethhdr = (struct ethhdr *)(((uint8_t *)skb->data) + hdr_size);

	if (ntohs(ethhdr->h_proto) == ETH_P_8021Q) {

		if (!pskb_may_pull(skb, hdr_size + sizeof(struct vlan_ethhdr)))

	if (ethhdr->h_proto == htons(ETH_P_8021Q)) {

		if (!pskb_may_pull(skb, hdr_size + VLAN_ETH_HLEN))

			return 0;

		vhdr = (struct vlan_ethhdr *)(skb->data + hdr_size);

#include "send.h"

#include "types.h"

#include "translation-table.h"

#include "unicast.h"

static void batadv_dat_purge(struct work_struct *work);

			goto free_orig;

		tmp_skb = pskb_copy(skb, GFP_ATOMIC);

		if (!batadv_unicast_4addr_prepare_skb(bat_priv, tmp_skb,

		if (!batadv_send_skb_prepare_unicast_4addr(bat_priv, tmp_skb,

							   cand[i].orig_node,

							   packet_subtype)) {

			kfree_skb(tmp_skb);

	 * that a node not using the 4addr packet format doesn't support it.

	 */

	if (hdr_size == sizeof(struct batadv_unicast_4addr_packet))

		err = batadv_unicast_4addr_send_skb(bat_priv, skb_new,

		err = batadv_send_skb_unicast_4addr(bat_priv, skb_new,

						    BATADV_P_DAT_CACHE_REPLY);

	else

		err = batadv_unicast_send_skb(bat_priv, skb_new);

		err = batadv_send_skb_unicast(bat_priv, skb_new);

	if (!err) {

		batadv_inc_counter(bat_priv, BATADV_CNT_DAT_CACHED_REPLY_TX);

/* Copyright (C) 2013 B.A.T.M.A.N. contributors:

 *

 * Martin Hundebøll <martin@hundeboll.net>

 *

 * 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 "fragmentation.h"

#include "send.h"

#include "originator.h"

#include "routing.h"

#include "hard-interface.h"

#include "soft-interface.h"

/**

 * batadv_frag_clear_chain - delete entries in the fragment buffer chain

 * @head: head of chain with entries.

 *

 * Free fragments in the passed hlist. Should be called with appropriate lock.

 */

static void batadv_frag_clear_chain(struct hlist_head *head)

{

	struct batadv_frag_list_entry *entry;

	struct hlist_node *node;

	hlist_for_each_entry_safe(entry, node, head, list) {

		hlist_del(&entry->list);

		kfree_skb(entry->skb);

		kfree(entry);

	}

}

/**

 * batadv_frag_purge_orig - free fragments associated to an orig

 * @orig_node: originator to free fragments from

 * @check_cb: optional function to tell if an entry should be purged

 */

void batadv_frag_purge_orig(struct batadv_orig_node *orig_node,

			    bool (*check_cb)(struct batadv_frag_table_entry *))

{

	struct batadv_frag_table_entry *chain;

	uint8_t i;

	for (i = 0; i < BATADV_FRAG_BUFFER_COUNT; i++) {

		chain = &orig_node->fragments[i];

		spin_lock_bh(&orig_node->fragments[i].lock);

		if (!check_cb || check_cb(chain)) {

			batadv_frag_clear_chain(&orig_node->fragments[i].head);

			orig_node->fragments[i].size = 0;

		}

		spin_unlock_bh(&orig_node->fragments[i].lock);

	}

}

/**

 * batadv_frag_size_limit - maximum possible size of packet to be fragmented

 *

 * Returns the maximum size of payload that can be fragmented.

 */

static int batadv_frag_size_limit(void)

{

	int limit = BATADV_FRAG_MAX_FRAG_SIZE;

	limit -= sizeof(struct batadv_frag_packet);

	limit *= BATADV_FRAG_MAX_FRAGMENTS;

	return limit;

}

/**

 * batadv_frag_init_chain - check and prepare fragment chain for new fragment

 * @chain: chain in fragments table to init

 * @seqno: sequence number of the received fragment

 *

 * Make chain ready for a fragment with sequence number "seqno". Delete existing

 * entries if they have an "old" sequence number.

 *

 * Caller must hold chain->lock.

 *

 * Returns true if chain is empty and caller can just insert the new fragment

 * without searching for the right position.

 */

static bool batadv_frag_init_chain(struct batadv_frag_table_entry *chain,

				   uint16_t seqno)

{

	if (chain->seqno == seqno)

		return false;

	if (!hlist_empty(&chain->head))

		batadv_frag_clear_chain(&chain->head);

	chain->size = 0;

	chain->seqno = seqno;

	return true;

}

/**

 * batadv_frag_insert_packet - insert a fragment into a fragment chain

 * @orig_node: originator that the fragment was received from

 * @skb: skb to insert

 * @chain_out: list head to attach complete chains of fragments to

 *

 * Insert a new fragment into the reverse ordered chain in the right table

 * entry. The hash table entry is cleared if "old" fragments exist in it.

 *

 * Returns true if skb is buffered, false on error. If the chain has all the

 * fragments needed to merge the packet, the chain is moved to the passed head

 * to avoid locking the chain in the table.

 */

static bool batadv_frag_insert_packet(struct batadv_orig_node *orig_node,

				      struct sk_buff *skb,

				      struct hlist_head *chain_out)

{

	struct batadv_frag_table_entry *chain;

	struct batadv_frag_list_entry *frag_entry_new = NULL, *frag_entry_curr;

	struct batadv_frag_packet *frag_packet;

	uint8_t bucket;

	uint16_t seqno, hdr_size = sizeof(struct batadv_frag_packet);

	bool ret = false;

	/* Linearize packet to avoid linearizing 16 packets in a row when doing

	 * the later merge. Non-linear merge should be added to remove this

	 * linearization.

	 */

	if (skb_linearize(skb) < 0)

		goto err;

	frag_packet = (struct batadv_frag_packet *)skb->data;

	seqno = ntohs(frag_packet->seqno);

	bucket = seqno % BATADV_FRAG_BUFFER_COUNT;

	frag_entry_new = kmalloc(sizeof(*frag_entry_new), GFP_ATOMIC);

	if (!frag_entry_new)

		goto err;

	frag_entry_new->skb = skb;

	frag_entry_new->no = frag_packet->no;

	/* Select entry in the "chain table" and delete any prior fragments

	 * with another sequence number. batadv_frag_init_chain() returns true,

	 * if the list is empty at return.

	 */

	chain = &orig_node->fragments[bucket];

	spin_lock_bh(&chain->lock);

	if (batadv_frag_init_chain(chain, seqno)) {

		hlist_add_head(&frag_entry_new->list, &chain->head);

		chain->size = skb->len - hdr_size;

		chain->timestamp = jiffies;

		ret = true;

		goto out;

	}

	/* Find the position for the new fragment. */

	hlist_for_each_entry(frag_entry_curr, &chain->head, list) {

		/* Drop packet if fragment already exists. */

		if (frag_entry_curr->no == frag_entry_new->no)

			goto err_unlock;

		/* Order fragments from highest to lowest. */

		if (frag_entry_curr->no < frag_entry_new->no) {

			hlist_add_before(&frag_entry_new->list,

					 &frag_entry_curr->list);

			chain->size += skb->len - hdr_size;

			chain->timestamp = jiffies;

			ret = true;

			goto out;

		}

	}

	/* Reached the end of the list, so insert after 'frag_entry_curr'. */

	if (likely(frag_entry_curr)) {

		hlist_add_after(&frag_entry_curr->list, &frag_entry_new->list);

		chain->size += skb->len - hdr_size;

		chain->timestamp = jiffies;

		ret = true;

	}

out:

	if (chain->size > batadv_frag_size_limit() ||

	    ntohs(frag_packet->total_size) > batadv_frag_size_limit()) {

		/* Clear chain if total size of either the list or the packet

		 * exceeds the maximum size of one merged packet.

		 */

		batadv_frag_clear_chain(&chain->head);

		chain->size = 0;

	} else if (ntohs(frag_packet->total_size) == chain->size) {

		/* All fragments received. Hand over chain to caller. */

		hlist_move_list(&chain->head, chain_out);

		chain->size = 0;

	}

err_unlock:

	spin_unlock_bh(&chain->lock);

err:

	if (!ret)

		kfree(frag_entry_new);

	return ret;

}

/**

 * batadv_frag_merge_packets - merge a chain of fragments

 * @chain: head of chain with fragments

 * @skb: packet with total size of skb after merging

 *

 * Expand the first skb in the chain and copy the content of the remaining

 * skb's into the expanded one. After doing so, clear the chain.

 *

 * Returns the merged skb or NULL on error.

 */

static struct sk_buff *

batadv_frag_merge_packets(struct hlist_head *chain, struct sk_buff *skb)

{

	struct batadv_frag_packet *packet;

	struct batadv_frag_list_entry *entry;

	struct sk_buff *skb_out = NULL;

	int size, hdr_size = sizeof(struct batadv_frag_packet);

	/* Make sure incoming skb has non-bogus data. */

	packet = (struct batadv_frag_packet *)skb->data;

	size = ntohs(packet->total_size);

	if (size > batadv_frag_size_limit())

		goto free;

	/* Remove first entry, as this is the destination for the rest of the

	 * fragments.

	 */

	entry = hlist_entry(chain->first, struct batadv_frag_list_entry, list);

	hlist_del(&entry->list);

	skb_out = entry->skb;

	kfree(entry);

	/* Make room for the rest of the fragments. */

	if (pskb_expand_head(skb_out, 0, size - skb->len, GFP_ATOMIC) < 0) {

		kfree_skb(skb_out);

		skb_out = NULL;

		goto free;

	}

	/* Move the existing MAC header to just before the payload. (Override

	 * the fragment header.)

	 */

	skb_pull_rcsum(skb_out, hdr_size);

	memmove(skb_out->data - ETH_HLEN, skb_mac_header(skb_out), ETH_HLEN);

	skb_set_mac_header(skb_out, -ETH_HLEN);

	skb_reset_network_header(skb_out);

	skb_reset_transport_header(skb_out);

	/* Copy the payload of the each fragment into the last skb */

	hlist_for_each_entry(entry, chain, list) {

		size = entry->skb->len - hdr_size;

		memcpy(skb_put(skb_out, size), entry->skb->data + hdr_size,

		       size);

	}

free:

	/* Locking is not needed, because 'chain' is not part of any orig. */

	batadv_frag_clear_chain(chain);

	return skb_out;

}

/**

 * batadv_frag_skb_buffer - buffer fragment for later merge

 * @skb: skb to buffer

 * @orig_node_src: originator that the skb is received from

 *

 * Add fragment to buffer and merge fragments if possible.

 *

 * There are three possible outcomes: 1) Packet is merged: Return true and

 * set *skb to merged packet; 2) Packet is buffered: Return true and set *skb

 * to NULL; 3) Error: Return false and leave skb as is.

 */

bool batadv_frag_skb_buffer(struct sk_buff **skb,

			    struct batadv_orig_node *orig_node_src)

{

	struct sk_buff *skb_out = NULL;

	struct hlist_head head = HLIST_HEAD_INIT;

	bool ret = false;

	/* Add packet to buffer and table entry if merge is possible. */

	if (!batadv_frag_insert_packet(orig_node_src, *skb, &head))

		goto out_err;

	/* Leave if more fragments are needed to merge. */

	if (hlist_empty(&head))

		goto out;

	skb_out = batadv_frag_merge_packets(&head, *skb);

	if (!skb_out)

		goto out_err;

out:

	*skb = skb_out;

	ret = true;

out_err:

	return ret;

}

/**

 * batadv_frag_skb_fwd - forward fragments that would exceed MTU when merged

 * @skb: skb to forward

 * @recv_if: interface that the skb is received on

 * @orig_node_src: originator that the skb is received from

 *

 * Look up the next-hop of the fragments payload and check if the merged packet

 * will exceed the MTU towards the next-hop. If so, the fragment is forwarded

 * without merging it.

 *

 * Returns true if the fragment is consumed/forwarded, false otherwise.

 */

bool batadv_frag_skb_fwd(struct sk_buff *skb,

			 struct batadv_hard_iface *recv_if,

			 struct batadv_orig_node *orig_node_src)

{

	struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);

	struct batadv_orig_node *orig_node_dst = NULL;

	struct batadv_neigh_node *neigh_node = NULL;

	struct batadv_frag_packet *packet;

	uint16_t total_size;

	bool ret = false;

	packet = (struct batadv_frag_packet *)skb->data;

	orig_node_dst = batadv_orig_hash_find(bat_priv, packet->dest);

	if (!orig_node_dst)

		goto out;

	neigh_node = batadv_find_router(bat_priv, orig_node_dst, recv_if);

	if (!neigh_node)

		goto out;

	/* Forward the fragment, if the merged packet would be too big to

	 * be assembled.

	 */

	total_size = ntohs(packet->total_size);

	if (total_size > neigh_node->if_incoming->net_dev->mtu) {

		batadv_inc_counter(bat_priv, BATADV_CNT_FRAG_FWD);

		batadv_add_counter(bat_priv, BATADV_CNT_FRAG_FWD_BYTES,

				   skb->len + ETH_HLEN);

		packet->header.ttl--;

		batadv_send_skb_packet(skb, neigh_node->if_incoming,

				       neigh_node->addr);

		ret = true;

	}

out:

	if (orig_node_dst)

		batadv_orig_node_free_ref(orig_node_dst);

	if (neigh_node)

		batadv_neigh_node_free_ref(neigh_node);

	return ret;

}

/**

 * batadv_frag_create - create a fragment from skb

 * @skb: skb to create fragment from

 * @frag_head: header to use in new fragment

 * @mtu: size of new fragment

 *

 * Split the passed skb into two fragments: A new one with size matching the

 * passed mtu and the old one with the rest. The new skb contains data from the

 * tail of the old skb.

 *

 * Returns the new fragment, NULL on error.

 */

static struct sk_buff *batadv_frag_create(struct sk_buff *skb,

					  struct batadv_frag_packet *frag_head,

					  unsigned int mtu)

{

	struct sk_buff *skb_fragment;

	unsigned header_size = sizeof(*frag_head);

	unsigned fragment_size = mtu - header_size;

	skb_fragment = netdev_alloc_skb(NULL, mtu + ETH_HLEN);

	if (!skb_fragment)

		goto err;

	skb->priority = TC_PRIO_CONTROL;

	/* Eat the last mtu-bytes of the skb */

	skb_reserve(skb_fragment, header_size + ETH_HLEN);

	skb_split(skb, skb_fragment, skb->len - fragment_size);

	/* Add the header */

	skb_push(skb_fragment, header_size);

	memcpy(skb_fragment->data, frag_head, header_size);

err:

	return skb_fragment;

}

/**

 * batadv_frag_send_packet - create up to 16 fragments from the passed skb

 * @skb: skb to create fragments from

 * @orig_node: final destination of the created fragments

 * @neigh_node: next-hop of the created fragments

 *

 * Returns true on success, false otherwise.

 */

bool batadv_frag_send_packet(struct sk_buff *skb,

			     struct batadv_orig_node *orig_node,

			     struct batadv_neigh_node *neigh_node)

{

	struct batadv_priv *bat_priv;

	struct batadv_hard_iface *primary_if;

	struct batadv_frag_packet frag_header;

	struct sk_buff *skb_fragment;

	unsigned mtu = neigh_node->if_incoming->net_dev->mtu;

	unsigned header_size = sizeof(frag_header);

	unsigned max_fragment_size, max_packet_size;

	/* To avoid merge and refragmentation at next-hops we never send

	 * fragments larger than BATADV_FRAG_MAX_FRAG_SIZE

	 */

	mtu = min_t(unsigned, mtu, BATADV_FRAG_MAX_FRAG_SIZE);

	max_fragment_size = (mtu - header_size - ETH_HLEN);

	max_packet_size = max_fragment_size * BATADV_FRAG_MAX_FRAGMENTS;

	/* Don't even try to fragment, if we need more than 16 fragments */

	if (skb->len > max_packet_size)

		goto out_err;

	bat_priv = orig_node->bat_priv;

	primary_if = batadv_primary_if_get_selected(bat_priv);

	if (!primary_if)

		goto out_err;

	/* Create one header to be copied to all fragments */

	frag_header.header.packet_type = BATADV_UNICAST_FRAG;

	frag_header.header.version = BATADV_COMPAT_VERSION;

	frag_header.header.ttl = BATADV_TTL;

	frag_header.seqno = htons(atomic_inc_return(&bat_priv->frag_seqno));

	frag_header.reserved = 0;

	frag_header.no = 0;

	frag_header.total_size = htons(skb->len);

	memcpy(frag_header.orig, primary_if->net_dev->dev_addr, ETH_ALEN);

	memcpy(frag_header.dest, orig_node->orig, ETH_ALEN);

	/* Eat and send fragments from the tail of skb */

	while (skb->len > max_fragment_size) {

		skb_fragment = batadv_frag_create(skb, &frag_header, mtu);

		if (!skb_fragment)

			goto out_err;

		batadv_inc_counter(bat_priv, BATADV_CNT_FRAG_TX);

		batadv_add_counter(bat_priv, BATADV_CNT_FRAG_TX_BYTES,

				   skb_fragment->len + ETH_HLEN);

		batadv_send_skb_packet(skb_fragment, neigh_node->if_incoming,

				       neigh_node->addr);

		frag_header.no++;

		/* The initial check in this function should cover this case */

		if (frag_header.no == BATADV_FRAG_MAX_FRAGMENTS - 1)

			goto out_err;

	}

	/* Make room for the fragment header. */

	if (batadv_skb_head_push(skb, header_size) < 0 ||

	    pskb_expand_head(skb, header_size + ETH_HLEN, 0, GFP_ATOMIC) < 0)

		goto out_err;

	memcpy(skb->data, &frag_header, header_size);

	/* Send the last fragment */

	batadv_inc_counter(bat_priv, BATADV_CNT_FRAG_TX);

	batadv_add_counter(bat_priv, BATADV_CNT_FRAG_TX_BYTES,

			   skb->len + ETH_HLEN);

	batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);

	return true;

out_err:

	return false;

}

/* Copyright (C) 2013 B.A.T.M.A.N. contributors:

 *

 * Martin Hundebøll <martin@hundeboll.net>

 *

 * 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

 */

#ifndef _NET_BATMAN_ADV_FRAGMENTATION_H_

#define _NET_BATMAN_ADV_FRAGMENTATION_H_

void batadv_frag_purge_orig(struct batadv_orig_node *orig,

			    bool (*check_cb)(struct batadv_frag_table_entry *));

bool batadv_frag_skb_fwd(struct sk_buff *skb,

			 struct batadv_hard_iface *recv_if,

			 struct batadv_orig_node *orig_node_src);

bool batadv_frag_skb_buffer(struct sk_buff **skb,

			    struct batadv_orig_node *orig_node);

bool batadv_frag_send_packet(struct sk_buff *skb,

			     struct batadv_orig_node *orig_node,

			     struct batadv_neigh_node *neigh_node);

/**

 * batadv_frag_check_entry - check if a list of fragments has timed out

 * @frags_entry: table entry to check

 *

 * Returns true if the frags entry has timed out, false otherwise.

 */

static inline bool

batadv_frag_check_entry(struct batadv_frag_table_entry *frags_entry)

{

	if (!hlist_empty(&frags_entry->head) &&

	    batadv_has_timed_out(frags_entry->timestamp, BATADV_FRAG_TIMEOUT))

		return true;

	else

		return false;

}

#endif /* _NET_BATMAN_ADV_FRAGMENTATION_H_ */