[linux-2.6-block.git] / net / batman-adv / icmp_socket.c

/* Copyright (C) 2007-2013 B.A.T.M.A.N. contributors:
 *
 * Marek Lindner
 *
 * 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 <linux/debugfs.h>
#include <linux/slab.h>
#include "icmp_socket.h"
#include "send.h"
#include "hash.h"
#include "originator.h"
#include "hard-interface.h"

static struct batadv_socket_client *batadv_socket_client_hash[256];

static void batadv_socket_add_packet(struct batadv_socket_client *socket_client,
				     struct batadv_icmp_header *icmph,
				     size_t icmp_len);

void batadv_socket_init(void)
{
	memset(batadv_socket_client_hash, 0, sizeof(batadv_socket_client_hash));
}

static int batadv_socket_open(struct inode *inode, struct file *file)
{
	unsigned int i;
	struct batadv_socket_client *socket_client;

	if (!try_module_get(THIS_MODULE))
		return -EBUSY;

	nonseekable_open(inode, file);

	socket_client = kmalloc(sizeof(*socket_client), GFP_KERNEL);
	if (!socket_client) {
		module_put(THIS_MODULE);
		return -ENOMEM;
	}

	for (i = 0; i < ARRAY_SIZE(batadv_socket_client_hash); i++) {
		if (!batadv_socket_client_hash[i]) {
			batadv_socket_client_hash[i] = socket_client;
			break;
		}
	}

	if (i == ARRAY_SIZE(batadv_socket_client_hash)) {
		pr_err("Error - can't add another packet client: maximum number of clients reached\n");
		kfree(socket_client);
		module_put(THIS_MODULE);
		return -EXFULL;
	}

	INIT_LIST_HEAD(&socket_client->queue_list);
	socket_client->queue_len = 0;
	socket_client->index = i;
	socket_client->bat_priv = inode->i_private;
	spin_lock_init(&socket_client->lock);
	init_waitqueue_head(&socket_client->queue_wait);

	file->private_data = socket_client;

	return 0;
}

static int batadv_socket_release(struct inode *inode, struct file *file)
{
	struct batadv_socket_client *socket_client = file->private_data;
	struct batadv_socket_packet *socket_packet;
	struct list_head *list_pos, *list_pos_tmp;

	spin_lock_bh(&socket_client->lock);

	/* for all packets in the queue ... */
	list_for_each_safe(list_pos, list_pos_tmp, &socket_client->queue_list) {
		socket_packet = list_entry(list_pos,
					   struct batadv_socket_packet, list);

		list_del(list_pos);
		kfree(socket_packet);
	}

	batadv_socket_client_hash[socket_client->index] = NULL;
	spin_unlock_bh(&socket_client->lock);

	kfree(socket_client);
	module_put(THIS_MODULE);

	return 0;
}

static ssize_t batadv_socket_read(struct file *file, char __user *buf,
				  size_t count, loff_t *ppos)
{
	struct batadv_socket_client *socket_client = file->private_data;
	struct batadv_socket_packet *socket_packet;
	size_t packet_len;
	int error;

	if ((file->f_flags & O_NONBLOCK) && (socket_client->queue_len == 0))
		return -EAGAIN;

	if ((!buf) || (count < sizeof(struct batadv_icmp_packet)))
		return -EINVAL;

	if (!access_ok(VERIFY_WRITE, buf, count))
		return -EFAULT;

	error = wait_event_interruptible(socket_client->queue_wait,
					 socket_client->queue_len);

	if (error)
		return error;

	spin_lock_bh(&socket_client->lock);

	socket_packet = list_first_entry(&socket_client->queue_list,
					 struct batadv_socket_packet, list);
	list_del(&socket_packet->list);
	socket_client->queue_len--;

	spin_unlock_bh(&socket_client->lock);

	packet_len = min(count, socket_packet->icmp_len);
	error = copy_to_user(buf, &socket_packet->icmp_packet, packet_len);

	kfree(socket_packet);

	if (error)
		return -EFAULT;

	return packet_len;
}

static ssize_t batadv_socket_write(struct file *file, const char __user *buff,
				   size_t len, loff_t *off)
{
	struct batadv_socket_client *socket_client = file->private_data;
	struct batadv_priv *bat_priv = socket_client->bat_priv;
	struct batadv_hard_iface *primary_if = NULL;
	struct sk_buff *skb;
	struct batadv_icmp_packet_rr *icmp_packet_rr;
	struct batadv_icmp_header *icmp_header;
	struct batadv_orig_node *orig_node = NULL;
	struct batadv_neigh_node *neigh_node = NULL;
	size_t packet_len = sizeof(struct batadv_icmp_packet);

	if (len < sizeof(struct batadv_icmp_header)) {
		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
			   "Error - can't send packet from char device: invalid packet size\n");
		return -EINVAL;
	}

	primary_if = batadv_primary_if_get_selected(bat_priv);

	if (!primary_if) {
		len = -EFAULT;
		goto out;
	}

	if (len >= BATADV_ICMP_MAX_PACKET_SIZE)
		packet_len = BATADV_ICMP_MAX_PACKET_SIZE;
	else
		packet_len = len;

	skb = netdev_alloc_skb_ip_align(NULL, packet_len + ETH_HLEN);
	if (!skb) {
		len = -ENOMEM;
		goto out;
	}

	skb->priority = TC_PRIO_CONTROL;
	skb_reserve(skb, ETH_HLEN);
	icmp_header = (struct batadv_icmp_header *)skb_put(skb, packet_len);

	if (copy_from_user(icmp_header, buff, packet_len)) {
		len = -EFAULT;
		goto free_skb;
	}

	if (icmp_header->packet_type != BATADV_ICMP) {
		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
			   "Error - can't send packet from char device: got bogus packet type (expected: BAT_ICMP)\n");
		len = -EINVAL;
		goto free_skb;
	}

	switch (icmp_header->msg_type) {
	case BATADV_ECHO_REQUEST:
		if (len < sizeof(struct batadv_icmp_packet)) {
			batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
				   "Error - can't send packet from char device: invalid packet size\n");
			len = -EINVAL;
			goto free_skb;
		}

		if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
			goto dst_unreach;

		orig_node = batadv_orig_hash_find(bat_priv, icmp_header->dst);
		if (!orig_node)
			goto dst_unreach;

		neigh_node = batadv_orig_node_get_router(orig_node);
		if (!neigh_node)
			goto dst_unreach;

		if (!neigh_node->if_incoming)
			goto dst_unreach;

		if (neigh_node->if_incoming->if_status != BATADV_IF_ACTIVE)
			goto dst_unreach;

		icmp_packet_rr = (struct batadv_icmp_packet_rr *)icmp_header;
		if (packet_len == sizeof(*icmp_packet_rr))
			memcpy(icmp_packet_rr->rr,
			       neigh_node->if_incoming->net_dev->dev_addr,
			       ETH_ALEN);

		break;
	default:
		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
			   "Error - can't send packet from char device: got unknown message type\n");
		len = -EINVAL;
		goto free_skb;
	}

	icmp_header->uid = socket_client->index;

	if (icmp_header->version != BATADV_COMPAT_VERSION) {
		icmp_header->msg_type = BATADV_PARAMETER_PROBLEM;
		icmp_header->version = BATADV_COMPAT_VERSION;
		batadv_socket_add_packet(socket_client, icmp_header,
					 packet_len);
		goto free_skb;
	}

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

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

dst_unreach:
	icmp_header->msg_type = BATADV_DESTINATION_UNREACHABLE;
	batadv_socket_add_packet(socket_client, icmp_header, packet_len);
free_skb:
	kfree_skb(skb);
out:
	if (primary_if)
		batadv_hardif_free_ref(primary_if);
	if (neigh_node)
		batadv_neigh_node_free_ref(neigh_node);
	if (orig_node)
		batadv_orig_node_free_ref(orig_node);
	return len;
}

static unsigned int batadv_socket_poll(struct file *file, poll_table *wait)
{
	struct batadv_socket_client *socket_client = file->private_data;

	poll_wait(file, &socket_client->queue_wait, wait);

	if (socket_client->queue_len > 0)
		return POLLIN | POLLRDNORM;

	return 0;
}

static const struct file_operations batadv_fops = {
	.owner = THIS_MODULE,
	.open = batadv_socket_open,
	.release = batadv_socket_release,
	.read = batadv_socket_read,
	.write = batadv_socket_write,
	.poll = batadv_socket_poll,
	.llseek = no_llseek,
};

int batadv_socket_setup(struct batadv_priv *bat_priv)
{
	struct dentry *d;

	if (!bat_priv->debug_dir)
		goto err;

	d = debugfs_create_file(BATADV_ICMP_SOCKET, S_IFREG | S_IWUSR | S_IRUSR,
				bat_priv->debug_dir, bat_priv, &batadv_fops);
	if (!d)
		goto err;

	return 0;

err:
	return -ENOMEM;
}

/**
 * batadv_socket_receive_packet - schedule an icmp packet to be sent to userspace
 *  on an icmp socket.
 * @socket_client: the socket this packet belongs to
 * @icmph: pointer to the header of the icmp packet
 * @icmp_len: total length of the icmp packet
 */
static void batadv_socket_add_packet(struct batadv_socket_client *socket_client,
				     struct batadv_icmp_header *icmph,
				     size_t icmp_len)
{
	struct batadv_socket_packet *socket_packet;
	size_t len;

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

	if (!socket_packet)
		return;

	len = icmp_len;
	/* check the maximum length before filling the buffer */
	if (len > sizeof(socket_packet->icmp_packet))
		len = sizeof(socket_packet->icmp_packet);

	INIT_LIST_HEAD(&socket_packet->list);
	memcpy(&socket_packet->icmp_packet, icmph, len);
	socket_packet->icmp_len = len;

	spin_lock_bh(&socket_client->lock);

	/* while waiting for the lock the socket_client could have been
	 * deleted
	 */
	if (!batadv_socket_client_hash[icmph->uid]) {
		spin_unlock_bh(&socket_client->lock);
		kfree(socket_packet);
		return;
	}

	list_add_tail(&socket_packet->list, &socket_client->queue_list);
	socket_client->queue_len++;

	if (socket_client->queue_len > 100) {
		socket_packet = list_first_entry(&socket_client->queue_list,
						 struct batadv_socket_packet,
						 list);

		list_del(&socket_packet->list);
		kfree(socket_packet);
		socket_client->queue_len--;
	}

	spin_unlock_bh(&socket_client->lock);

	wake_up(&socket_client->queue_wait);
}

/**
 * batadv_socket_receive_packet - schedule an icmp packet to be received
 *  locally and sent to userspace.
 * @icmph: pointer to the header of the icmp packet
 * @icmp_len: total length of the icmp packet
 */
void batadv_socket_receive_packet(struct batadv_icmp_header *icmph,
				  size_t icmp_len)
{
	struct batadv_socket_client *hash;

	hash = batadv_socket_client_hash[icmph->uid];
	if (hash)
		batadv_socket_add_packet(hash, icmph, icmp_len);
}
Commit	Line	Data
0b873931	1	/* Copyright (C) 2007-2013 B.A.T.M.A.N. contributors:
c6c8fea2 SE	2	*
	3	* Marek Lindner
	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 <linux/debugfs.h>
	22	#include <linux/slab.h>
	23	#include "icmp_socket.h"
	24	#include "send.h"
c6c8fea2 SE	25	#include "hash.h"
	26	#include "originator.h"
	27	#include "hard-interface.h"
	28
56303d34	29	static struct batadv_socket_client *batadv_socket_client_hash[256];
c6c8fea2	30
56303d34	31	static void batadv_socket_add_packet(struct batadv_socket_client *socket_client,
da6b8c20	32	struct batadv_icmp_header *icmph,
af4447f6	33	size_t icmp_len);
c6c8fea2	34
9039dc7e	35	void batadv_socket_init(void)
c6c8fea2	36	{
af4447f6	37	memset(batadv_socket_client_hash, 0, sizeof(batadv_socket_client_hash));
c6c8fea2 SE	38	}
c6c8fea2 SE	39
af4447f6	40	static int batadv_socket_open(struct inode inode, struct file file)
c6c8fea2 SE	41	{
c6c8fea2 SE	42	unsigned int i;
56303d34	43	struct batadv_socket_client *socket_client;
c6c8fea2	44
bd5b80d5 SE	45	if (!try_module_get(THIS_MODULE))
	46	return -EBUSY;
	47
c6c8fea2 SE	48	nonseekable_open(inode, file);
c6c8fea2 SE	49
704509b8	50	socket_client = kmalloc(sizeof(*socket_client), GFP_KERNEL);
bd5b80d5 SE	51	if (!socket_client) {
bd5b80d5 SE	52	module_put(THIS_MODULE);
c6c8fea2	53	return -ENOMEM;
bd5b80d5	54	}
c6c8fea2	55
af4447f6 SE	56	for (i = 0; i < ARRAY_SIZE(batadv_socket_client_hash); i++) {
	57	if (!batadv_socket_client_hash[i]) {
	58	batadv_socket_client_hash[i] = socket_client;
c6c8fea2 SE	59	break;
	60	}
	61	}
	62
af4447f6	63	if (i == ARRAY_SIZE(batadv_socket_client_hash)) {
86ceb360	64	pr_err("Error - can't add another packet client: maximum number of clients reached\n");
c6c8fea2	65	kfree(socket_client);
bd5b80d5	66	module_put(THIS_MODULE);
c6c8fea2 SE	67	return -EXFULL;
	68	}
	69
	70	INIT_LIST_HEAD(&socket_client->queue_list);
	71	socket_client->queue_len = 0;
	72	socket_client->index = i;
	73	socket_client->bat_priv = inode->i_private;
	74	spin_lock_init(&socket_client->lock);
	75	init_waitqueue_head(&socket_client->queue_wait);
	76
	77	file->private_data = socket_client;
	78
c6c8fea2 SE	79	return 0;
	80	}
	81
af4447f6	82	static int batadv_socket_release(struct inode inode, struct file file)
c6c8fea2	83	{
56303d34 SE	84	struct batadv_socket_client *socket_client = file->private_data;
56303d34 SE	85	struct batadv_socket_packet *socket_packet;
c6c8fea2 SE	86	struct list_head list_pos, list_pos_tmp;
	87
	88	spin_lock_bh(&socket_client->lock);
	89
	90	/* for all packets in the queue ... */
	91	list_for_each_safe(list_pos, list_pos_tmp, &socket_client->queue_list) {
	92	socket_packet = list_entry(list_pos,
56303d34	93	struct batadv_socket_packet, list);
c6c8fea2 SE	94
	95	list_del(list_pos);
	96	kfree(socket_packet);
	97	}
	98
af4447f6	99	batadv_socket_client_hash[socket_client->index] = NULL;
c6c8fea2 SE	100	spin_unlock_bh(&socket_client->lock);
	101
	102	kfree(socket_client);
bd5b80d5	103	module_put(THIS_MODULE);
c6c8fea2 SE	104
	105	return 0;
	106	}
	107
af4447f6 SE	108	static ssize_t batadv_socket_read(struct file file, char __user buf,
af4447f6 SE	109	size_t count, loff_t *ppos)
c6c8fea2	110	{
56303d34 SE	111	struct batadv_socket_client *socket_client = file->private_data;
56303d34 SE	112	struct batadv_socket_packet *socket_packet;
c6c8fea2 SE	113	size_t packet_len;
	114	int error;
	115
	116	if ((file->f_flags & O_NONBLOCK) && (socket_client->queue_len == 0))
	117	return -EAGAIN;
	118
96412690	119	if ((!buf) \|\| (count < sizeof(struct batadv_icmp_packet)))
c6c8fea2 SE	120	return -EINVAL;
	121
	122	if (!access_ok(VERIFY_WRITE, buf, count))
	123	return -EFAULT;
	124
	125	error = wait_event_interruptible(socket_client->queue_wait,
	126	socket_client->queue_len);
	127
	128	if (error)
	129	return error;
	130
	131	spin_lock_bh(&socket_client->lock);
	132
	133	socket_packet = list_first_entry(&socket_client->queue_list,
56303d34	134	struct batadv_socket_packet, list);
c6c8fea2 SE	135	list_del(&socket_packet->list);
	136	socket_client->queue_len--;
	137
	138	spin_unlock_bh(&socket_client->lock);
	139
b5a1eeef SE	140	packet_len = min(count, socket_packet->icmp_len);
b5a1eeef SE	141	error = copy_to_user(buf, &socket_packet->icmp_packet, packet_len);
c6c8fea2	142
c6c8fea2 SE	143	kfree(socket_packet);
	144
	145	if (error)
	146	return -EFAULT;
	147
	148	return packet_len;
	149	}
	150
af4447f6 SE	151	static ssize_t batadv_socket_write(struct file file, const char __user buff,
af4447f6 SE	152	size_t len, loff_t *off)
c6c8fea2	153	{
56303d34 SE	154	struct batadv_socket_client *socket_client = file->private_data;
	155	struct batadv_priv *bat_priv = socket_client->bat_priv;
	156	struct batadv_hard_iface *primary_if = NULL;
c6c8fea2	157	struct sk_buff *skb;
da6b8c20 SW	158	struct batadv_icmp_packet_rr *icmp_packet_rr;
da6b8c20 SW	159	struct batadv_icmp_header *icmp_header;
56303d34 SE	160	struct batadv_orig_node *orig_node = NULL;
56303d34 SE	161	struct batadv_neigh_node *neigh_node = NULL;
96412690	162	size_t packet_len = sizeof(struct batadv_icmp_packet);
c6c8fea2	163
da6b8c20	164	if (len < sizeof(struct batadv_icmp_header)) {
39c75a51	165	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1eda58bf	166	"Error - can't send packet from char device: invalid packet size\n");
c6c8fea2 SE	167	return -EINVAL;
	168	}
	169
e5d89254	170	primary_if = batadv_primary_if_get_selected(bat_priv);
32ae9b22 ML	171
	172	if (!primary_if) {
	173	len = -EFAULT;
	174	goto out;
	175	}
c6c8fea2	176
da6b8c20 SW	177	if (len >= BATADV_ICMP_MAX_PACKET_SIZE)
	178	packet_len = BATADV_ICMP_MAX_PACKET_SIZE;
	179	else
	180	packet_len = len;
c6c8fea2	181
41ab6c48	182	skb = netdev_alloc_skb_ip_align(NULL, packet_len + ETH_HLEN);
32ae9b22 ML	183	if (!skb) {
	184	len = -ENOMEM;
	185	goto out;
	186	}
c6c8fea2	187
c54f38c9	188	skb->priority = TC_PRIO_CONTROL;
41ab6c48	189	skb_reserve(skb, ETH_HLEN);
da6b8c20	190	icmp_header = (struct batadv_icmp_header *)skb_put(skb, packet_len);
c6c8fea2	191
da6b8c20	192	if (copy_from_user(icmp_header, buff, packet_len)) {
c6c8fea2 SE	193	len = -EFAULT;
	194	goto free_skb;
	195	}
	196
a40d9b07	197	if (icmp_header->packet_type != BATADV_ICMP) {
39c75a51	198	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1eda58bf	199	"Error - can't send packet from char device: got bogus packet type (expected: BAT_ICMP)\n");
c6c8fea2 SE	200	len = -EINVAL;
	201	goto free_skb;
	202	}
	203
da6b8c20 SW	204	switch (icmp_header->msg_type) {
	205	case BATADV_ECHO_REQUEST:
	206	if (len < sizeof(struct batadv_icmp_packet)) {
	207	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
	208	"Error - can't send packet from char device: invalid packet size\n");
	209	len = -EINVAL;
	210	goto free_skb;
	211	}
	212
	213	if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
	214	goto dst_unreach;
	215
	216	orig_node = batadv_orig_hash_find(bat_priv, icmp_header->dst);
	217	if (!orig_node)
	218	goto dst_unreach;
	219
	220	neigh_node = batadv_orig_node_get_router(orig_node);
	221	if (!neigh_node)
	222	goto dst_unreach;
	223
	224	if (!neigh_node->if_incoming)
	225	goto dst_unreach;
	226
	227	if (neigh_node->if_incoming->if_status != BATADV_IF_ACTIVE)
	228	goto dst_unreach;
	229
	230	icmp_packet_rr = (struct batadv_icmp_packet_rr *)icmp_header;
	231	if (packet_len == sizeof(*icmp_packet_rr))
	232	memcpy(icmp_packet_rr->rr,
	233	neigh_node->if_incoming->net_dev->dev_addr,
	234	ETH_ALEN);
	235
	236	break;
	237	default:
39c75a51	238	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
da6b8c20	239	"Error - can't send packet from char device: got unknown message type\n");
c6c8fea2 SE	240	len = -EINVAL;
	241	goto free_skb;
	242	}
	243
da6b8c20	244	icmp_header->uid = socket_client->index;
c6c8fea2	245
a40d9b07	246	if (icmp_header->version != BATADV_COMPAT_VERSION) {
da6b8c20	247	icmp_header->msg_type = BATADV_PARAMETER_PROBLEM;
a40d9b07	248	icmp_header->version = BATADV_COMPAT_VERSION;
da6b8c20	249	batadv_socket_add_packet(socket_client, icmp_header,
af4447f6	250	packet_len);
c6c8fea2 SE	251	goto free_skb;
	252	}
	253
da6b8c20	254	memcpy(icmp_header->orig, primary_if->net_dev->dev_addr, ETH_ALEN);
c6c8fea2	255
9455e34c	256	batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
c6c8fea2 SE	257	goto out;
c6c8fea2 SE	258
c6c8fea2	259	dst_unreach:
da6b8c20 SW	260	icmp_header->msg_type = BATADV_DESTINATION_UNREACHABLE;
da6b8c20 SW	261	batadv_socket_add_packet(socket_client, icmp_header, packet_len);
c6c8fea2 SE	262	free_skb:
	263	kfree_skb(skb);
	264	out:
32ae9b22	265	if (primary_if)
e5d89254	266	batadv_hardif_free_ref(primary_if);
44524fcd	267	if (neigh_node)
7d211efc	268	batadv_neigh_node_free_ref(neigh_node);
44524fcd	269	if (orig_node)
7d211efc	270	batadv_orig_node_free_ref(orig_node);
c6c8fea2 SE	271	return len;
	272	}
	273
af4447f6	274	static unsigned int batadv_socket_poll(struct file file, poll_table wait)
c6c8fea2	275	{
56303d34	276	struct batadv_socket_client *socket_client = file->private_data;
c6c8fea2 SE	277
	278	poll_wait(file, &socket_client->queue_wait, wait);
	279
	280	if (socket_client->queue_len > 0)
	281	return POLLIN \| POLLRDNORM;
	282
	283	return 0;
	284	}
	285
af4447f6	286	static const struct file_operations batadv_fops = {
c6c8fea2	287	.owner = THIS_MODULE,
af4447f6 SE	288	.open = batadv_socket_open,
	289	.release = batadv_socket_release,
	290	.read = batadv_socket_read,
	291	.write = batadv_socket_write,
	292	.poll = batadv_socket_poll,
c6c8fea2 SE	293	.llseek = no_llseek,
	294	};
	295
56303d34	296	int batadv_socket_setup(struct batadv_priv *bat_priv)
c6c8fea2 SE	297	{
	298	struct dentry *d;
	299
	300	if (!bat_priv->debug_dir)
	301	goto err;
	302
64346643	303	d = debugfs_create_file(BATADV_ICMP_SOCKET, S_IFREG \| S_IWUSR \| S_IRUSR,
af4447f6	304	bat_priv->debug_dir, bat_priv, &batadv_fops);
5346c35e	305	if (!d)
c6c8fea2 SE	306	goto err;
	307
	308	return 0;
	309
	310	err:
5346c35e	311	return -ENOMEM;
c6c8fea2 SE	312	}
c6c8fea2 SE	313
da6b8c20 SW	314	/**
	315	* batadv_socket_receive_packet - schedule an icmp packet to be sent to userspace
	316	* on an icmp socket.
	317	* @socket_client: the socket this packet belongs to
	318	* @icmph: pointer to the header of the icmp packet
	319	* @icmp_len: total length of the icmp packet
	320	*/
56303d34	321	static void batadv_socket_add_packet(struct batadv_socket_client *socket_client,
da6b8c20	322	struct batadv_icmp_header *icmph,
af4447f6	323	size_t icmp_len)
c6c8fea2	324	{
56303d34	325	struct batadv_socket_packet *socket_packet;
da6b8c20	326	size_t len;
c6c8fea2	327
704509b8	328	socket_packet = kmalloc(sizeof(*socket_packet), GFP_ATOMIC);
c6c8fea2 SE	329
	330	if (!socket_packet)
	331	return;
	332
da6b8c20 SW	333	len = icmp_len;
	334	/* check the maximum length before filling the buffer */
	335	if (len > sizeof(socket_packet->icmp_packet))
	336	len = sizeof(socket_packet->icmp_packet);
	337
c6c8fea2	338	INIT_LIST_HEAD(&socket_packet->list);
da6b8c20 SW	339	memcpy(&socket_packet->icmp_packet, icmph, len);
da6b8c20 SW	340	socket_packet->icmp_len = len;
c6c8fea2 SE	341
	342	spin_lock_bh(&socket_client->lock);
	343
	344	/* while waiting for the lock the socket_client could have been
9cfc7bd6 SE	345	* deleted
9cfc7bd6 SE	346	*/
da6b8c20	347	if (!batadv_socket_client_hash[icmph->uid]) {
c6c8fea2 SE	348	spin_unlock_bh(&socket_client->lock);
	349	kfree(socket_packet);
	350	return;
	351	}
	352
	353	list_add_tail(&socket_packet->list, &socket_client->queue_list);
	354	socket_client->queue_len++;
	355
	356	if (socket_client->queue_len > 100) {
	357	socket_packet = list_first_entry(&socket_client->queue_list,
56303d34 SE	358	struct batadv_socket_packet,
56303d34 SE	359	list);
c6c8fea2 SE	360
	361	list_del(&socket_packet->list);
	362	kfree(socket_packet);
	363	socket_client->queue_len--;
	364	}
	365
	366	spin_unlock_bh(&socket_client->lock);
	367
	368	wake_up(&socket_client->queue_wait);
	369	}
	370
da6b8c20 SW	371	/**
	372	* batadv_socket_receive_packet - schedule an icmp packet to be received
	373	* locally and sent to userspace.
	374	* @icmph: pointer to the header of the icmp packet
	375	* @icmp_len: total length of the icmp packet
	376	*/
	377	void batadv_socket_receive_packet(struct batadv_icmp_header *icmph,
9039dc7e	378	size_t icmp_len)
c6c8fea2	379	{
56303d34	380	struct batadv_socket_client *hash;
c6c8fea2	381
da6b8c20	382	hash = batadv_socket_client_hash[icmph->uid];
c6c8fea2	383	if (hash)
da6b8c20	384	batadv_socket_add_packet(hash, icmph, icmp_len);
c6c8fea2	385	}