[deliverable/linux.git] / net / batman-adv / unicast.c

/* Copyright (C) 2010-2012 B.A.T.M.A.N. contributors:
 *
 * Andreas Langer
 *
 * 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 "unicast.h"
#include "send.h"
#include "soft-interface.h"
#include "gateway_client.h"
#include "originator.h"
#include "hash.h"
#include "translation-table.h"
#include "routing.h"
#include "hard-interface.h"


static struct sk_buff *
batadv_frag_merge_packet(struct list_head *head,
			 struct batadv_frag_packet_list_entry *tfp,
			 struct sk_buff *skb)
{
	struct batadv_unicast_frag_packet *up;
	struct sk_buff *tmp_skb;
	struct batadv_unicast_packet *unicast_packet;
	int hdr_len = sizeof(*unicast_packet);
	int uni_diff = sizeof(*up) - hdr_len;

	up = (struct batadv_unicast_frag_packet *)skb->data;
	/* set skb to the first part and tmp_skb to the second part */
	if (up->flags & BATADV_UNI_FRAG_HEAD) {
		tmp_skb = tfp->skb;
	} else {
		tmp_skb = skb;
		skb = tfp->skb;
	}

	if (skb_linearize(skb) < 0 || skb_linearize(tmp_skb) < 0)
		goto err;

	skb_pull(tmp_skb, sizeof(*up));
	if (pskb_expand_head(skb, 0, tmp_skb->len, GFP_ATOMIC) < 0)
		goto err;

	/* move free entry to end */
	tfp->skb = NULL;
	tfp->seqno = 0;
	list_move_tail(&tfp->list, head);

	memcpy(skb_put(skb, tmp_skb->len), tmp_skb->data, tmp_skb->len);
	kfree_skb(tmp_skb);

	memmove(skb->data + uni_diff, skb->data, hdr_len);
	unicast_packet = (struct batadv_unicast_packet *)skb_pull(skb,
								  uni_diff);
	unicast_packet->header.packet_type = BATADV_UNICAST;

	return skb;

err:
	/* free buffered skb, skb will be freed later */
	kfree_skb(tfp->skb);
	return NULL;
}

static void batadv_frag_create_entry(struct list_head *head,
				     struct sk_buff *skb)
{
	struct batadv_frag_packet_list_entry *tfp;
	struct batadv_unicast_frag_packet *up;

	up = (struct batadv_unicast_frag_packet *)skb->data;

	/* free and oldest packets stand at the end */
	tfp = list_entry((head)->prev, typeof(*tfp), list);
	kfree_skb(tfp->skb);

	tfp->seqno = ntohs(up->seqno);
	tfp->skb = skb;
	list_move(&tfp->list, head);
	return;
}

static int batadv_frag_create_buffer(struct list_head *head)
{
	int i;
	struct batadv_frag_packet_list_entry *tfp;

	for (i = 0; i < BATADV_FRAG_BUFFER_SIZE; i++) {
		tfp = kmalloc(sizeof(*tfp), GFP_ATOMIC);
		if (!tfp) {
			batadv_frag_list_free(head);
			return -ENOMEM;
		}
		tfp->skb = NULL;
		tfp->seqno = 0;
		INIT_LIST_HEAD(&tfp->list);
		list_add(&tfp->list, head);
	}

	return 0;
}

static struct batadv_frag_packet_list_entry *
batadv_frag_search_packet(struct list_head *head,
			  const struct batadv_unicast_frag_packet *up)
{
	struct batadv_frag_packet_list_entry *tfp;
	struct batadv_unicast_frag_packet *tmp_up = NULL;
	uint16_t search_seqno;

	if (up->flags & BATADV_UNI_FRAG_HEAD)
		search_seqno = ntohs(up->seqno)+1;
	else
		search_seqno = ntohs(up->seqno)-1;

	list_for_each_entry(tfp, head, list) {

		if (!tfp->skb)
			continue;

		if (tfp->seqno == ntohs(up->seqno))
			goto mov_tail;

		tmp_up = (struct batadv_unicast_frag_packet *)tfp->skb->data;

		if (tfp->seqno == search_seqno) {

			if ((tmp_up->flags & BATADV_UNI_FRAG_HEAD) !=
			    (up->flags & BATADV_UNI_FRAG_HEAD))
				return tfp;
			else
				goto mov_tail;
		}
	}
	return NULL;

mov_tail:
	list_move_tail(&tfp->list, head);
	return NULL;
}

void batadv_frag_list_free(struct list_head *head)
{
	struct batadv_frag_packet_list_entry *pf, *tmp_pf;

	if (!list_empty(head)) {

		list_for_each_entry_safe(pf, tmp_pf, head, list) {
			kfree_skb(pf->skb);
			list_del(&pf->list);
			kfree(pf);
		}
	}
	return;
}

/* frag_reassemble_skb():
 * returns NET_RX_DROP if the operation failed - skb is left intact
 * returns NET_RX_SUCCESS if the fragment was buffered (skb_new will be NULL)
 * or the skb could be reassembled (skb_new will point to the new packet and
 * skb was freed)
 */
int batadv_frag_reassemble_skb(struct sk_buff *skb,
			       struct batadv_priv *bat_priv,
			       struct sk_buff **new_skb)
{
	struct batadv_orig_node *orig_node;
	struct batadv_frag_packet_list_entry *tmp_frag_entry;
	int ret = NET_RX_DROP;
	struct batadv_unicast_frag_packet *unicast_packet;

	unicast_packet = (struct batadv_unicast_frag_packet *)skb->data;
	*new_skb = NULL;

	orig_node = batadv_orig_hash_find(bat_priv, unicast_packet->orig);
	if (!orig_node)
		goto out;

	orig_node->last_frag_packet = jiffies;

	if (list_empty(&orig_node->frag_list) &&
	    batadv_frag_create_buffer(&orig_node->frag_list)) {
		pr_debug("couldn't create frag buffer\n");
		goto out;
	}

	tmp_frag_entry = batadv_frag_search_packet(&orig_node->frag_list,
						   unicast_packet);

	if (!tmp_frag_entry) {
		batadv_frag_create_entry(&orig_node->frag_list, skb);
		ret = NET_RX_SUCCESS;
		goto out;
	}

	*new_skb = batadv_frag_merge_packet(&orig_node->frag_list,
					    tmp_frag_entry, skb);
	/* if not, merge failed */
	if (*new_skb)
		ret = NET_RX_SUCCESS;

out:
	if (orig_node)
		batadv_orig_node_free_ref(orig_node);
	return ret;
}

int batadv_frag_send_skb(struct sk_buff *skb, struct batadv_priv *bat_priv,
			 struct batadv_hard_iface *hard_iface,
			 const uint8_t dstaddr[])
{
	struct batadv_unicast_packet tmp_uc, *unicast_packet;
	struct batadv_hard_iface *primary_if;
	struct sk_buff *frag_skb;
	struct batadv_unicast_frag_packet *frag1, *frag2;
	int uc_hdr_len = sizeof(*unicast_packet);
	int ucf_hdr_len = sizeof(*frag1);
	int data_len = skb->len - uc_hdr_len;
	int large_tail = 0, ret = NET_RX_DROP;
	uint16_t seqno;

	primary_if = batadv_primary_if_get_selected(bat_priv);
	if (!primary_if)
		goto dropped;

	frag_skb = dev_alloc_skb(data_len - (data_len / 2) + ucf_hdr_len);
	if (!frag_skb)
		goto dropped;
	skb_reserve(frag_skb, ucf_hdr_len);

	unicast_packet = (struct batadv_unicast_packet *)skb->data;
	memcpy(&tmp_uc, unicast_packet, uc_hdr_len);
	skb_split(skb, frag_skb, data_len / 2 + uc_hdr_len);

	if (batadv_skb_head_push(skb, ucf_hdr_len - uc_hdr_len) < 0 ||
	    batadv_skb_head_push(frag_skb, ucf_hdr_len) < 0)
		goto drop_frag;

	frag1 = (struct batadv_unicast_frag_packet *)skb->data;
	frag2 = (struct batadv_unicast_frag_packet *)frag_skb->data;

	memcpy(frag1, &tmp_uc, sizeof(tmp_uc));

	frag1->header.ttl--;
	frag1->header.version = BATADV_COMPAT_VERSION;
	frag1->header.packet_type = BATADV_UNICAST_FRAG;

	memcpy(frag1->orig, primary_if->net_dev->dev_addr, ETH_ALEN);
	memcpy(frag2, frag1, sizeof(*frag2));

	if (data_len & 1)
		large_tail = BATADV_UNI_FRAG_LARGETAIL;

	frag1->flags = BATADV_UNI_FRAG_HEAD | large_tail;
	frag2->flags = large_tail;

	seqno = atomic_add_return(2, &hard_iface->frag_seqno);
	frag1->seqno = htons(seqno - 1);
	frag2->seqno = htons(seqno);

	batadv_send_skb_packet(skb, hard_iface, dstaddr);
	batadv_send_skb_packet(frag_skb, hard_iface, dstaddr);
	ret = NET_RX_SUCCESS;
	goto out;

drop_frag:
	kfree_skb(frag_skb);
dropped:
	kfree_skb(skb);
out:
	if (primary_if)
		batadv_hardif_free_ref(primary_if);
	return ret;
}

int batadv_unicast_send_skb(struct sk_buff *skb, struct batadv_priv *bat_priv)
{
	struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
	struct batadv_unicast_packet *unicast_packet;
	struct batadv_orig_node *orig_node;
	struct batadv_neigh_node *neigh_node;
	int data_len = skb->len;
	int ret = 1;
	unsigned int dev_mtu;

	/* get routing information */
	if (is_multicast_ether_addr(ethhdr->h_dest)) {
		orig_node = batadv_gw_get_selected_orig(bat_priv);
		if (orig_node)
			goto find_router;
	}

	/* check for tt host - increases orig_node refcount.
	 * returns NULL in case of AP isolation
	 */
	orig_node = batadv_transtable_search(bat_priv, ethhdr->h_source,
					     ethhdr->h_dest);

find_router:
	/* find_router():
	 *  - if orig_node is NULL it returns NULL
	 *  - increases neigh_nodes refcount if found.
	 */
	neigh_node = batadv_find_router(bat_priv, orig_node, NULL);

	if (!neigh_node)
		goto out;

	if (batadv_skb_head_push(skb, sizeof(*unicast_packet)) < 0)
		goto out;

	unicast_packet = (struct batadv_unicast_packet *)skb->data;

	unicast_packet->header.version = BATADV_COMPAT_VERSION;
	/* batman packet type: unicast */
	unicast_packet->header.packet_type = BATADV_UNICAST;
	/* set unicast ttl */
	unicast_packet->header.ttl = BATADV_TTL;
	/* copy the destination for faster routing */
	memcpy(unicast_packet->dest, orig_node->orig, ETH_ALEN);
	/* set the destination tt version number */
	unicast_packet->ttvn =
		(uint8_t)atomic_read(&orig_node->last_ttvn);

	/* inform the destination node that we are still missing a correct route
	 * for this client. The destination will receive this packet and will
	 * try to reroute it because the ttvn contained in the header is less
	 * than the current one
	 */
	if (batadv_tt_global_client_is_roaming(bat_priv, ethhdr->h_dest))
		unicast_packet->ttvn = unicast_packet->ttvn - 1;

	dev_mtu = neigh_node->if_incoming->net_dev->mtu;
	if (atomic_read(&bat_priv->fragmentation) &&
	    data_len + sizeof(*unicast_packet) > dev_mtu) {
		/* send frag skb decreases ttl */
		unicast_packet->header.ttl++;
		ret = batadv_frag_send_skb(skb, bat_priv,
					   neigh_node->if_incoming,
					   neigh_node->addr);
		goto out;
	}

	batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
	ret = 0;
	goto out;

out:
	if (neigh_node)
		batadv_neigh_node_free_ref(neigh_node);
	if (orig_node)
		batadv_orig_node_free_ref(orig_node);
	if (ret == 1)
		kfree_skb(skb);
	return ret;
}
Commit	Line	Data
9cfc7bd6	1	/* Copyright (C) 2010-2012 B.A.T.M.A.N. contributors:
c6c8fea2 SE	2	*
	3	* Andreas Langer
	4	*
	5	* This program is free software; you can redistribute it and/or
	6	* modify it under the terms of version 2 of the GNU General Public
	7	* License as published by the Free Software Foundation.
	8	*
	9	* This program is distributed in the hope that it will be useful, but
	10	* WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	12	* General Public License for more details.
	13	*
	14	* You should have received a copy of the GNU General Public License
	15	* along with this program; if not, write to the Free Software
	16	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
	17	* 02110-1301, USA
c6c8fea2 SE	18	*/
	19
	20	#include "main.h"
	21	#include "unicast.h"
	22	#include "send.h"
	23	#include "soft-interface.h"
	24	#include "gateway_client.h"
	25	#include "originator.h"
	26	#include "hash.h"
	27	#include "translation-table.h"
	28	#include "routing.h"
	29	#include "hard-interface.h"
	30
	31
0354440b SE	32	static struct sk_buff *
0354440b SE	33	batadv_frag_merge_packet(struct list_head *head,
56303d34	34	struct batadv_frag_packet_list_entry *tfp,
0354440b	35	struct sk_buff *skb)
c6c8fea2	36	{
96412690	37	struct batadv_unicast_frag_packet *up;
c6c8fea2	38	struct sk_buff *tmp_skb;
96412690	39	struct batadv_unicast_packet *unicast_packet;
704509b8 SE	40	int hdr_len = sizeof(*unicast_packet);
704509b8 SE	41	int uni_diff = sizeof(*up) - hdr_len;
c6c8fea2	42
96412690	43	up = (struct batadv_unicast_frag_packet *)skb->data;
c6c8fea2	44	/* set skb to the first part and tmp_skb to the second part */
acd34afa	45	if (up->flags & BATADV_UNI_FRAG_HEAD) {
c6c8fea2 SE	46	tmp_skb = tfp->skb;
	47	} else {
	48	tmp_skb = skb;
	49	skb = tfp->skb;
	50	}
	51
531c9da8 SE	52	if (skb_linearize(skb) < 0 \|\| skb_linearize(tmp_skb) < 0)
	53	goto err;
	54
704509b8	55	skb_pull(tmp_skb, sizeof(*up));
531c9da8 SE	56	if (pskb_expand_head(skb, 0, tmp_skb->len, GFP_ATOMIC) < 0)
531c9da8 SE	57	goto err;
c6c8fea2 SE	58
	59	/* move free entry to end */
	60	tfp->skb = NULL;
	61	tfp->seqno = 0;
	62	list_move_tail(&tfp->list, head);
	63
	64	memcpy(skb_put(skb, tmp_skb->len), tmp_skb->data, tmp_skb->len);
	65	kfree_skb(tmp_skb);
	66
	67	memmove(skb->data + uni_diff, skb->data, hdr_len);
96412690 SE	68	unicast_packet = (struct batadv_unicast_packet *)skb_pull(skb,
96412690 SE	69	uni_diff);
acd34afa	70	unicast_packet->header.packet_type = BATADV_UNICAST;
c6c8fea2 SE	71
c6c8fea2 SE	72	return skb;
531c9da8 SE	73
	74	err:
	75	/* free buffered skb, skb will be freed later */
	76	kfree_skb(tfp->skb);
	77	return NULL;
c6c8fea2 SE	78	}
c6c8fea2 SE	79
0354440b SE	80	static void batadv_frag_create_entry(struct list_head *head,
0354440b SE	81	struct sk_buff *skb)
c6c8fea2	82	{
56303d34	83	struct batadv_frag_packet_list_entry *tfp;
96412690 SE	84	struct batadv_unicast_frag_packet *up;
	85
	86	up = (struct batadv_unicast_frag_packet *)skb->data;
c6c8fea2 SE	87
	88	/* free and oldest packets stand at the end */
	89	tfp = list_entry((head)->prev, typeof(*tfp), list);
	90	kfree_skb(tfp->skb);
	91
	92	tfp->seqno = ntohs(up->seqno);
	93	tfp->skb = skb;
	94	list_move(&tfp->list, head);
	95	return;
	96	}
	97
0354440b	98	static int batadv_frag_create_buffer(struct list_head *head)
c6c8fea2 SE	99	{
c6c8fea2 SE	100	int i;
56303d34	101	struct batadv_frag_packet_list_entry *tfp;
c6c8fea2	102
4d5d2db8	103	for (i = 0; i < BATADV_FRAG_BUFFER_SIZE; i++) {
704509b8	104	tfp = kmalloc(sizeof(*tfp), GFP_ATOMIC);
c6c8fea2	105	if (!tfp) {
88ed1e77	106	batadv_frag_list_free(head);
c6c8fea2 SE	107	return -ENOMEM;
	108	}
	109	tfp->skb = NULL;
	110	tfp->seqno = 0;
	111	INIT_LIST_HEAD(&tfp->list);
	112	list_add(&tfp->list, head);
	113	}
	114
	115	return 0;
	116	}
	117
56303d34	118	static struct batadv_frag_packet_list_entry *
0354440b	119	batadv_frag_search_packet(struct list_head *head,
96412690	120	const struct batadv_unicast_frag_packet *up)
c6c8fea2	121	{
56303d34	122	struct batadv_frag_packet_list_entry *tfp;
96412690	123	struct batadv_unicast_frag_packet *tmp_up = NULL;
c6c8fea2 SE	124	uint16_t search_seqno;
c6c8fea2 SE	125
acd34afa	126	if (up->flags & BATADV_UNI_FRAG_HEAD)
c6c8fea2 SE	127	search_seqno = ntohs(up->seqno)+1;
	128	else
	129	search_seqno = ntohs(up->seqno)-1;
	130
	131	list_for_each_entry(tfp, head, list) {
	132
	133	if (!tfp->skb)
	134	continue;
	135
	136	if (tfp->seqno == ntohs(up->seqno))
	137	goto mov_tail;
	138
96412690	139	tmp_up = (struct batadv_unicast_frag_packet *)tfp->skb->data;
c6c8fea2 SE	140
	141	if (tfp->seqno == search_seqno) {
	142
acd34afa SE	143	if ((tmp_up->flags & BATADV_UNI_FRAG_HEAD) !=
acd34afa SE	144	(up->flags & BATADV_UNI_FRAG_HEAD))
c6c8fea2 SE	145	return tfp;
	146	else
	147	goto mov_tail;
	148	}
	149	}
	150	return NULL;
	151
	152	mov_tail:
	153	list_move_tail(&tfp->list, head);
	154	return NULL;
	155	}
	156
88ed1e77	157	void batadv_frag_list_free(struct list_head *head)
c6c8fea2	158	{
56303d34	159	struct batadv_frag_packet_list_entry pf, tmp_pf;
c6c8fea2 SE	160
	161	if (!list_empty(head)) {
	162
	163	list_for_each_entry_safe(pf, tmp_pf, head, list) {
	164	kfree_skb(pf->skb);
	165	list_del(&pf->list);
	166	kfree(pf);
	167	}
	168	}
	169	return;
	170	}
	171
	172	/* frag_reassemble_skb():
	173	* returns NET_RX_DROP if the operation failed - skb is left intact
	174	* returns NET_RX_SUCCESS if the fragment was buffered (skb_new will be NULL)
	175	* or the skb could be reassembled (skb_new will point to the new packet and
	176	* skb was freed)
	177	*/
56303d34 SE	178	int batadv_frag_reassemble_skb(struct sk_buff *skb,
56303d34 SE	179	struct batadv_priv *bat_priv,
88ed1e77	180	struct sk_buff **new_skb)
c6c8fea2	181	{
56303d34 SE	182	struct batadv_orig_node *orig_node;
56303d34 SE	183	struct batadv_frag_packet_list_entry *tmp_frag_entry;
c6c8fea2	184	int ret = NET_RX_DROP;
96412690	185	struct batadv_unicast_frag_packet *unicast_packet;
c6c8fea2	186
96412690	187	unicast_packet = (struct batadv_unicast_frag_packet *)skb->data;
c6c8fea2	188	*new_skb = NULL;
c6c8fea2	189
da641193	190	orig_node = batadv_orig_hash_find(bat_priv, unicast_packet->orig);
7aadf889	191	if (!orig_node)
c6c8fea2	192	goto out;
c6c8fea2 SE	193
	194	orig_node->last_frag_packet = jiffies;
	195
	196	if (list_empty(&orig_node->frag_list) &&
0354440b	197	batadv_frag_create_buffer(&orig_node->frag_list)) {
c6c8fea2 SE	198	pr_debug("couldn't create frag buffer\n");
	199	goto out;
	200	}
	201
0354440b SE	202	tmp_frag_entry = batadv_frag_search_packet(&orig_node->frag_list,
0354440b SE	203	unicast_packet);
c6c8fea2 SE	204
c6c8fea2 SE	205	if (!tmp_frag_entry) {
0354440b	206	batadv_frag_create_entry(&orig_node->frag_list, skb);
c6c8fea2 SE	207	ret = NET_RX_SUCCESS;
	208	goto out;
	209	}
	210
0354440b SE	211	*new_skb = batadv_frag_merge_packet(&orig_node->frag_list,
0354440b SE	212	tmp_frag_entry, skb);
c6c8fea2 SE	213	/* if not, merge failed */
	214	if (*new_skb)
	215	ret = NET_RX_SUCCESS;
c6c8fea2	216
7aadf889 ML	217	out:
7aadf889 ML	218	if (orig_node)
7d211efc	219	batadv_orig_node_free_ref(orig_node);
c6c8fea2 SE	220	return ret;
	221	}
	222
56303d34 SE	223	int batadv_frag_send_skb(struct sk_buff skb, struct batadv_priv bat_priv,
	224	struct batadv_hard_iface *hard_iface,
	225	const uint8_t dstaddr[])
c6c8fea2	226	{
96412690	227	struct batadv_unicast_packet tmp_uc, *unicast_packet;
56303d34	228	struct batadv_hard_iface *primary_if;
c6c8fea2	229	struct sk_buff *frag_skb;
96412690	230	struct batadv_unicast_frag_packet frag1, frag2;
704509b8 SE	231	int uc_hdr_len = sizeof(*unicast_packet);
704509b8 SE	232	int ucf_hdr_len = sizeof(*frag1);
5c77d8bb	233	int data_len = skb->len - uc_hdr_len;
32ae9b22	234	int large_tail = 0, ret = NET_RX_DROP;
c2f7f0e7	235	uint16_t seqno;
c6c8fea2	236
e5d89254	237	primary_if = batadv_primary_if_get_selected(bat_priv);
32ae9b22	238	if (!primary_if)
c6c8fea2 SE	239	goto dropped;
c6c8fea2 SE	240
ed7809d9 JJ	241	frag_skb = dev_alloc_skb(data_len - (data_len / 2) + ucf_hdr_len);
	242	if (!frag_skb)
	243	goto dropped;
5c77d8bb	244	skb_reserve(frag_skb, ucf_hdr_len);
c6c8fea2	245
96412690	246	unicast_packet = (struct batadv_unicast_packet *)skb->data;
c6c8fea2	247	memcpy(&tmp_uc, unicast_packet, uc_hdr_len);
5c77d8bb	248	skb_split(skb, frag_skb, data_len / 2 + uc_hdr_len);
c6c8fea2	249
04b482a2 SE	250	if (batadv_skb_head_push(skb, ucf_hdr_len - uc_hdr_len) < 0 \|\|
04b482a2 SE	251	batadv_skb_head_push(frag_skb, ucf_hdr_len) < 0)
c6c8fea2 SE	252	goto drop_frag;
c6c8fea2 SE	253
96412690 SE	254	frag1 = (struct batadv_unicast_frag_packet *)skb->data;
96412690 SE	255	frag2 = (struct batadv_unicast_frag_packet *)frag_skb->data;
c6c8fea2	256
704509b8	257	memcpy(frag1, &tmp_uc, sizeof(tmp_uc));
c6c8fea2	258
76543d14	259	frag1->header.ttl--;
7e071c79	260	frag1->header.version = BATADV_COMPAT_VERSION;
acd34afa	261	frag1->header.packet_type = BATADV_UNICAST_FRAG;
c6c8fea2	262
32ae9b22	263	memcpy(frag1->orig, primary_if->net_dev->dev_addr, ETH_ALEN);
704509b8	264	memcpy(frag2, frag1, sizeof(*frag2));
c6c8fea2	265
ae361ce1	266	if (data_len & 1)
acd34afa	267	large_tail = BATADV_UNI_FRAG_LARGETAIL;
ae361ce1	268
acd34afa	269	frag1->flags = BATADV_UNI_FRAG_HEAD \| large_tail;
ae361ce1	270	frag2->flags = large_tail;
c6c8fea2	271
e6c10f43	272	seqno = atomic_add_return(2, &hard_iface->frag_seqno);
c2f7f0e7 SE	273	frag1->seqno = htons(seqno - 1);
c2f7f0e7 SE	274	frag2->seqno = htons(seqno);
c6c8fea2	275
9455e34c SE	276	batadv_send_skb_packet(skb, hard_iface, dstaddr);
9455e34c SE	277	batadv_send_skb_packet(frag_skb, hard_iface, dstaddr);
32ae9b22 ML	278	ret = NET_RX_SUCCESS;
32ae9b22 ML	279	goto out;
c6c8fea2 SE	280
	281	drop_frag:
	282	kfree_skb(frag_skb);
	283	dropped:
	284	kfree_skb(skb);
32ae9b22 ML	285	out:
32ae9b22 ML	286	if (primary_if)
e5d89254	287	batadv_hardif_free_ref(primary_if);
32ae9b22	288	return ret;
c6c8fea2 SE	289	}
c6c8fea2 SE	290
56303d34	291	int batadv_unicast_send_skb(struct sk_buff skb, struct batadv_priv bat_priv)
c6c8fea2 SE	292	{
c6c8fea2 SE	293	struct ethhdr ethhdr = (struct ethhdr )skb->data;
96412690	294	struct batadv_unicast_packet *unicast_packet;
56303d34 SE	295	struct batadv_orig_node *orig_node;
56303d34 SE	296	struct batadv_neigh_node *neigh_node;
c6c8fea2	297	int data_len = skb->len;
44524fcd	298	int ret = 1;
0aca2369	299	unsigned int dev_mtu;
c6c8fea2 SE	300
c6c8fea2 SE	301	/* get routing information */
43c70ad5	302	if (is_multicast_ether_addr(ethhdr->h_dest)) {
7cf06bc6	303	orig_node = batadv_gw_get_selected_orig(bat_priv);
43c70ad5	304	if (orig_node)
44524fcd ML	305	goto find_router;
44524fcd ML	306	}
c6c8fea2	307
3d393e47	308	/* check for tt host - increases orig_node refcount.
9cfc7bd6 SE	309	* returns NULL in case of AP isolation
9cfc7bd6 SE	310	*/
08c36d3e SE	311	orig_node = batadv_transtable_search(bat_priv, ethhdr->h_source,
08c36d3e SE	312	ethhdr->h_dest);
56303d34	313
44524fcd	314	find_router:
9cfc7bd6	315	/* find_router():
d0072609 ML	316	* - if orig_node is NULL it returns NULL
	317	* - increases neigh_nodes refcount if found.
	318	*/
30d3c511	319	neigh_node = batadv_find_router(bat_priv, orig_node, NULL);
56303d34	320
44524fcd	321	if (!neigh_node)
d0072609	322	goto out;
c6c8fea2	323
04b482a2	324	if (batadv_skb_head_push(skb, sizeof(*unicast_packet)) < 0)
d0072609	325	goto out;
c6c8fea2	326
96412690	327	unicast_packet = (struct batadv_unicast_packet *)skb->data;
c6c8fea2	328
7e071c79	329	unicast_packet->header.version = BATADV_COMPAT_VERSION;
c6c8fea2	330	/* batman packet type: unicast */
acd34afa	331	unicast_packet->header.packet_type = BATADV_UNICAST;
c6c8fea2	332	/* set unicast ttl */
42d0b044	333	unicast_packet->header.ttl = BATADV_TTL;
c6c8fea2 SE	334	/* copy the destination for faster routing */
c6c8fea2 SE	335	memcpy(unicast_packet->dest, orig_node->orig, ETH_ALEN);
a73105b8 AQ	336	/* set the destination tt version number */
	337	unicast_packet->ttvn =
	338	(uint8_t)atomic_read(&orig_node->last_ttvn);
c6c8fea2	339
3275e7cc AQ	340	/* inform the destination node that we are still missing a correct route
	341	* for this client. The destination will receive this packet and will
	342	* try to reroute it because the ttvn contained in the header is less
	343	* than the current one
	344	*/
08c36d3e	345	if (batadv_tt_global_client_is_roaming(bat_priv, ethhdr->h_dest))
3275e7cc AQ	346	unicast_packet->ttvn = unicast_packet->ttvn - 1;
3275e7cc AQ	347
0aca2369	348	dev_mtu = neigh_node->if_incoming->net_dev->mtu;
c6c8fea2	349	if (atomic_read(&bat_priv->fragmentation) &&
0aca2369	350	data_len + sizeof(*unicast_packet) > dev_mtu) {
c6c8fea2	351	/* send frag skb decreases ttl */
76543d14	352	unicast_packet->header.ttl++;
88ed1e77 SE	353	ret = batadv_frag_send_skb(skb, bat_priv,
	354	neigh_node->if_incoming,
	355	neigh_node->addr);
44524fcd	356	goto out;
c6c8fea2	357	}
c6c8fea2	358
9455e34c	359	batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
44524fcd ML	360	ret = 0;
44524fcd ML	361	goto out;
c6c8fea2	362
44524fcd ML	363	out:
44524fcd ML	364	if (neigh_node)
7d211efc	365	batadv_neigh_node_free_ref(neigh_node);
44524fcd	366	if (orig_node)
7d211efc	367	batadv_orig_node_free_ref(orig_node);
44524fcd ML	368	if (ret == 1)
	369	kfree_skb(skb);
	370	return ret;
c6c8fea2	371	}