[mirror_ubuntu-zesty-kernel.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 frag_packet_list_entry *tfp,
			 struct sk_buff *skb)
{
	struct unicast_frag_packet *up =
		(struct unicast_frag_packet *)skb->data;
	struct sk_buff *tmp_skb;
	struct unicast_packet *unicast_packet;
	int hdr_len = sizeof(*unicast_packet);
	int uni_diff = sizeof(*up) - hdr_len;

	/* set skb to the first part and tmp_skb to the second part */
	if (up->flags & 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 unicast_packet *)skb_pull(skb, uni_diff);
	unicast_packet->header.packet_type = BAT_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 frag_packet_list_entry *tfp;
	struct unicast_frag_packet *up =
		(struct 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 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 frag_packet_list_entry *
batadv_frag_search_packet(struct list_head *head,
			  const struct unicast_frag_packet *up)
{
	struct frag_packet_list_entry *tfp;
	struct unicast_frag_packet *tmp_up = NULL;
	uint16_t search_seqno;

	if (up->flags & 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 unicast_frag_packet *)tfp->skb->data;

		if (tfp->seqno == search_seqno) {

			if ((tmp_up->flags & UNI_FRAG_HEAD) !=
			    (up->flags & 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 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 bat_priv *bat_priv,
			       struct sk_buff **new_skb)
{
	struct orig_node *orig_node;
	struct frag_packet_list_entry *tmp_frag_entry;
	int ret = NET_RX_DROP;
	struct unicast_frag_packet *unicast_packet =
		(struct 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 bat_priv *bat_priv,
			 struct hard_iface *hard_iface, const uint8_t dstaddr[])
{
	struct unicast_packet tmp_uc, *unicast_packet;
	struct hard_iface *primary_if;
	struct sk_buff *frag_skb;
	struct 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 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 unicast_frag_packet *)skb->data;
	frag2 = (struct 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 = BAT_UNICAST_FRAG;

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

	if (data_len & 1)
		large_tail = UNI_FRAG_LARGETAIL;

	frag1->flags = 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 bat_priv *bat_priv)
{
	struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
	struct unicast_packet *unicast_packet;
	struct orig_node *orig_node;
	struct neigh_node *neigh_node;
	int data_len = skb->len;
	int ret = 1;

	/* 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 unicast_packet *)skb->data;

	unicast_packet->header.version = BATADV_COMPAT_VERSION;
	/* batman packet type: unicast */
	unicast_packet->header.packet_type = BAT_UNICAST;
	/* set unicast ttl */
	unicast_packet->header.ttl = 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;

	if (atomic_read(&bat_priv->fragmentation) &&
	    data_len + sizeof(*unicast_packet) >
				neigh_node->if_incoming->net_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 *
	33	batadv_frag_merge_packet(struct list_head *head,
	34	struct frag_packet_list_entry *tfp,
	35	struct sk_buff *skb)
c6c8fea2 SE	36	{
	37	struct unicast_frag_packet *up =
	38	(struct unicast_frag_packet *)skb->data;
	39	struct sk_buff *tmp_skb;
	40	struct unicast_packet *unicast_packet;
704509b8 SE	41	int hdr_len = sizeof(*unicast_packet);
704509b8 SE	42	int uni_diff = sizeof(*up) - hdr_len;
c6c8fea2 SE	43
	44	/* set skb to the first part and tmp_skb to the second part */
	45	if (up->flags & UNI_FRAG_HEAD) {
	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);
40e0c4f5	68	unicast_packet = (struct unicast_packet *)skb_pull(skb, uni_diff);
76543d14	69	unicast_packet->header.packet_type = BAT_UNICAST;
c6c8fea2 SE	70
c6c8fea2 SE	71	return skb;
531c9da8 SE	72
	73	err:
	74	/* free buffered skb, skb will be freed later */
	75	kfree_skb(tfp->skb);
	76	return NULL;
c6c8fea2 SE	77	}
c6c8fea2 SE	78
0354440b SE	79	static void batadv_frag_create_entry(struct list_head *head,
0354440b SE	80	struct sk_buff *skb)
c6c8fea2 SE	81	{
	82	struct frag_packet_list_entry *tfp;
	83	struct unicast_frag_packet *up =
	84	(struct unicast_frag_packet *)skb->data;
	85
	86	/* free and oldest packets stand at the end */
	87	tfp = list_entry((head)->prev, typeof(*tfp), list);
	88	kfree_skb(tfp->skb);
	89
	90	tfp->seqno = ntohs(up->seqno);
	91	tfp->skb = skb;
	92	list_move(&tfp->list, head);
	93	return;
	94	}
	95
0354440b	96	static int batadv_frag_create_buffer(struct list_head *head)
c6c8fea2 SE	97	{
	98	int i;
	99	struct frag_packet_list_entry *tfp;
	100
4d5d2db8	101	for (i = 0; i < BATADV_FRAG_BUFFER_SIZE; i++) {
704509b8	102	tfp = kmalloc(sizeof(*tfp), GFP_ATOMIC);
c6c8fea2	103	if (!tfp) {
88ed1e77	104	batadv_frag_list_free(head);
c6c8fea2 SE	105	return -ENOMEM;
	106	}
	107	tfp->skb = NULL;
	108	tfp->seqno = 0;
	109	INIT_LIST_HEAD(&tfp->list);
	110	list_add(&tfp->list, head);
	111	}
	112
	113	return 0;
	114	}
	115
0354440b SE	116	static struct frag_packet_list_entry *
	117	batadv_frag_search_packet(struct list_head *head,
	118	const struct unicast_frag_packet *up)
c6c8fea2 SE	119	{
	120	struct frag_packet_list_entry *tfp;
	121	struct unicast_frag_packet *tmp_up = NULL;
	122	uint16_t search_seqno;
	123
	124	if (up->flags & UNI_FRAG_HEAD)
	125	search_seqno = ntohs(up->seqno)+1;
	126	else
	127	search_seqno = ntohs(up->seqno)-1;
	128
	129	list_for_each_entry(tfp, head, list) {
	130
	131	if (!tfp->skb)
	132	continue;
	133
	134	if (tfp->seqno == ntohs(up->seqno))
	135	goto mov_tail;
	136
	137	tmp_up = (struct unicast_frag_packet *)tfp->skb->data;
	138
	139	if (tfp->seqno == search_seqno) {
	140
	141	if ((tmp_up->flags & UNI_FRAG_HEAD) !=
	142	(up->flags & UNI_FRAG_HEAD))
	143	return tfp;
	144	else
	145	goto mov_tail;
	146	}
	147	}
	148	return NULL;
	149
	150	mov_tail:
	151	list_move_tail(&tfp->list, head);
	152	return NULL;
	153	}
	154
88ed1e77	155	void batadv_frag_list_free(struct list_head *head)
c6c8fea2 SE	156	{
	157	struct frag_packet_list_entry pf, tmp_pf;
	158
	159	if (!list_empty(head)) {
	160
	161	list_for_each_entry_safe(pf, tmp_pf, head, list) {
	162	kfree_skb(pf->skb);
	163	list_del(&pf->list);
	164	kfree(pf);
	165	}
	166	}
	167	return;
	168	}
	169
	170	/* frag_reassemble_skb():
	171	* returns NET_RX_DROP if the operation failed - skb is left intact
	172	* returns NET_RX_SUCCESS if the fragment was buffered (skb_new will be NULL)
	173	* or the skb could be reassembled (skb_new will point to the new packet and
	174	* skb was freed)
	175	*/
88ed1e77 SE	176	int batadv_frag_reassemble_skb(struct sk_buff skb, struct bat_priv bat_priv,
88ed1e77 SE	177	struct sk_buff **new_skb)
c6c8fea2 SE	178	{
	179	struct orig_node *orig_node;
	180	struct frag_packet_list_entry *tmp_frag_entry;
	181	int ret = NET_RX_DROP;
	182	struct unicast_frag_packet *unicast_packet =
	183	(struct unicast_frag_packet *)skb->data;
	184
	185	*new_skb = NULL;
c6c8fea2	186
da641193	187	orig_node = batadv_orig_hash_find(bat_priv, unicast_packet->orig);
7aadf889	188	if (!orig_node)
c6c8fea2	189	goto out;
c6c8fea2 SE	190
	191	orig_node->last_frag_packet = jiffies;
	192
	193	if (list_empty(&orig_node->frag_list) &&
0354440b	194	batadv_frag_create_buffer(&orig_node->frag_list)) {
c6c8fea2 SE	195	pr_debug("couldn't create frag buffer\n");
	196	goto out;
	197	}
	198
0354440b SE	199	tmp_frag_entry = batadv_frag_search_packet(&orig_node->frag_list,
0354440b SE	200	unicast_packet);
c6c8fea2 SE	201
c6c8fea2 SE	202	if (!tmp_frag_entry) {
0354440b	203	batadv_frag_create_entry(&orig_node->frag_list, skb);
c6c8fea2 SE	204	ret = NET_RX_SUCCESS;
	205	goto out;
	206	}
	207
0354440b SE	208	*new_skb = batadv_frag_merge_packet(&orig_node->frag_list,
0354440b SE	209	tmp_frag_entry, skb);
c6c8fea2 SE	210	/* if not, merge failed */
	211	if (*new_skb)
	212	ret = NET_RX_SUCCESS;
c6c8fea2	213
7aadf889 ML	214	out:
7aadf889 ML	215	if (orig_node)
7d211efc	216	batadv_orig_node_free_ref(orig_node);
c6c8fea2 SE	217	return ret;
	218	}
	219
88ed1e77 SE	220	int batadv_frag_send_skb(struct sk_buff skb, struct bat_priv bat_priv,
88ed1e77 SE	221	struct hard_iface *hard_iface, const uint8_t dstaddr[])
c6c8fea2 SE	222	{
c6c8fea2 SE	223	struct unicast_packet tmp_uc, *unicast_packet;
32ae9b22	224	struct hard_iface *primary_if;
c6c8fea2 SE	225	struct sk_buff *frag_skb;
c6c8fea2 SE	226	struct unicast_frag_packet frag1, frag2;
704509b8 SE	227	int uc_hdr_len = sizeof(*unicast_packet);
704509b8 SE	228	int ucf_hdr_len = sizeof(*frag1);
5c77d8bb	229	int data_len = skb->len - uc_hdr_len;
32ae9b22	230	int large_tail = 0, ret = NET_RX_DROP;
c2f7f0e7	231	uint16_t seqno;
c6c8fea2	232
e5d89254	233	primary_if = batadv_primary_if_get_selected(bat_priv);
32ae9b22	234	if (!primary_if)
c6c8fea2 SE	235	goto dropped;
c6c8fea2 SE	236
ed7809d9 JJ	237	frag_skb = dev_alloc_skb(data_len - (data_len / 2) + ucf_hdr_len);
	238	if (!frag_skb)
	239	goto dropped;
5c77d8bb	240	skb_reserve(frag_skb, ucf_hdr_len);
c6c8fea2	241
40e0c4f5	242	unicast_packet = (struct unicast_packet *)skb->data;
c6c8fea2	243	memcpy(&tmp_uc, unicast_packet, uc_hdr_len);
5c77d8bb	244	skb_split(skb, frag_skb, data_len / 2 + uc_hdr_len);
c6c8fea2	245
04b482a2 SE	246	if (batadv_skb_head_push(skb, ucf_hdr_len - uc_hdr_len) < 0 \|\|
04b482a2 SE	247	batadv_skb_head_push(frag_skb, ucf_hdr_len) < 0)
c6c8fea2 SE	248	goto drop_frag;
	249
	250	frag1 = (struct unicast_frag_packet *)skb->data;
	251	frag2 = (struct unicast_frag_packet *)frag_skb->data;
	252
704509b8	253	memcpy(frag1, &tmp_uc, sizeof(tmp_uc));
c6c8fea2	254
76543d14	255	frag1->header.ttl--;
7e071c79	256	frag1->header.version = BATADV_COMPAT_VERSION;
76543d14	257	frag1->header.packet_type = BAT_UNICAST_FRAG;
c6c8fea2	258
32ae9b22	259	memcpy(frag1->orig, primary_if->net_dev->dev_addr, ETH_ALEN);
704509b8	260	memcpy(frag2, frag1, sizeof(*frag2));
c6c8fea2	261
ae361ce1 SE	262	if (data_len & 1)
	263	large_tail = UNI_FRAG_LARGETAIL;
	264
	265	frag1->flags = UNI_FRAG_HEAD \| large_tail;
	266	frag2->flags = large_tail;
c6c8fea2	267
e6c10f43	268	seqno = atomic_add_return(2, &hard_iface->frag_seqno);
c2f7f0e7 SE	269	frag1->seqno = htons(seqno - 1);
c2f7f0e7 SE	270	frag2->seqno = htons(seqno);
c6c8fea2	271
9455e34c SE	272	batadv_send_skb_packet(skb, hard_iface, dstaddr);
9455e34c SE	273	batadv_send_skb_packet(frag_skb, hard_iface, dstaddr);
32ae9b22 ML	274	ret = NET_RX_SUCCESS;
32ae9b22 ML	275	goto out;
c6c8fea2 SE	276
	277	drop_frag:
	278	kfree_skb(frag_skb);
	279	dropped:
	280	kfree_skb(skb);
32ae9b22 ML	281	out:
32ae9b22 ML	282	if (primary_if)
e5d89254	283	batadv_hardif_free_ref(primary_if);
32ae9b22	284	return ret;
c6c8fea2 SE	285	}
c6c8fea2 SE	286
88ed1e77	287	int batadv_unicast_send_skb(struct sk_buff skb, struct bat_priv bat_priv)
c6c8fea2 SE	288	{
	289	struct ethhdr ethhdr = (struct ethhdr )skb->data;
	290	struct unicast_packet *unicast_packet;
7b36e8ee	291	struct orig_node *orig_node;
44524fcd	292	struct neigh_node *neigh_node;
c6c8fea2	293	int data_len = skb->len;
44524fcd	294	int ret = 1;
c6c8fea2 SE	295
c6c8fea2 SE	296	/* get routing information */
43c70ad5	297	if (is_multicast_ether_addr(ethhdr->h_dest)) {
7cf06bc6	298	orig_node = batadv_gw_get_selected_orig(bat_priv);
43c70ad5	299	if (orig_node)
44524fcd ML	300	goto find_router;
44524fcd ML	301	}
c6c8fea2	302
3d393e47	303	/* check for tt host - increases orig_node refcount.
9cfc7bd6 SE	304	* returns NULL in case of AP isolation
9cfc7bd6 SE	305	*/
08c36d3e SE	306	orig_node = batadv_transtable_search(bat_priv, ethhdr->h_source,
08c36d3e SE	307	ethhdr->h_dest);
44524fcd	308	find_router:
9cfc7bd6	309	/* find_router():
d0072609 ML	310	* - if orig_node is NULL it returns NULL
	311	* - increases neigh_nodes refcount if found.
	312	*/
30d3c511	313	neigh_node = batadv_find_router(bat_priv, orig_node, NULL);
44524fcd	314	if (!neigh_node)
d0072609	315	goto out;
c6c8fea2	316
04b482a2	317	if (batadv_skb_head_push(skb, sizeof(*unicast_packet)) < 0)
d0072609	318	goto out;
c6c8fea2 SE	319
	320	unicast_packet = (struct unicast_packet *)skb->data;
	321
7e071c79	322	unicast_packet->header.version = BATADV_COMPAT_VERSION;
c6c8fea2	323	/* batman packet type: unicast */
76543d14	324	unicast_packet->header.packet_type = BAT_UNICAST;
c6c8fea2	325	/* set unicast ttl */
76543d14	326	unicast_packet->header.ttl = TTL;
c6c8fea2 SE	327	/* copy the destination for faster routing */
c6c8fea2 SE	328	memcpy(unicast_packet->dest, orig_node->orig, ETH_ALEN);
a73105b8 AQ	329	/* set the destination tt version number */
	330	unicast_packet->ttvn =
	331	(uint8_t)atomic_read(&orig_node->last_ttvn);
c6c8fea2	332
3275e7cc AQ	333	/* inform the destination node that we are still missing a correct route
	334	* for this client. The destination will receive this packet and will
	335	* try to reroute it because the ttvn contained in the header is less
	336	* than the current one
	337	*/
08c36d3e	338	if (batadv_tt_global_client_is_roaming(bat_priv, ethhdr->h_dest))
3275e7cc AQ	339	unicast_packet->ttvn = unicast_packet->ttvn - 1;
3275e7cc AQ	340
c6c8fea2	341	if (atomic_read(&bat_priv->fragmentation) &&
704509b8	342	data_len + sizeof(*unicast_packet) >
d0072609	343	neigh_node->if_incoming->net_dev->mtu) {
c6c8fea2	344	/* send frag skb decreases ttl */
76543d14	345	unicast_packet->header.ttl++;
88ed1e77 SE	346	ret = batadv_frag_send_skb(skb, bat_priv,
	347	neigh_node->if_incoming,
	348	neigh_node->addr);
44524fcd	349	goto out;
c6c8fea2	350	}
c6c8fea2	351
9455e34c	352	batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
44524fcd ML	353	ret = 0;
44524fcd ML	354	goto out;
c6c8fea2	355
44524fcd ML	356	out:
44524fcd ML	357	if (neigh_node)
7d211efc	358	batadv_neigh_node_free_ref(neigh_node);
44524fcd	359	if (orig_node)
7d211efc	360	batadv_orig_node_free_ref(orig_node);
44524fcd ML	361	if (ret == 1)
	362	kfree_skb(skb);
	363	return ret;
c6c8fea2	364	}