[deliverable/linux.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, see <http://www.gnu.org/licenses/>.
 */

#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_router_get(orig_node,
						    BATADV_IF_DEFAULT);
		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
ebf38fb7	15	* along with this program; if not, see <http://www.gnu.org/licenses/>.
c6c8fea2 SE	16	*/
	17
	18	#include "main.h"
	19	#include <linux/debugfs.h>
	20	#include <linux/slab.h>
	21	#include "icmp_socket.h"
	22	#include "send.h"
c6c8fea2 SE	23	#include "hash.h"
	24	#include "originator.h"
	25	#include "hard-interface.h"
	26
56303d34	27	static struct batadv_socket_client *batadv_socket_client_hash[256];
c6c8fea2	28
56303d34	29	static void batadv_socket_add_packet(struct batadv_socket_client *socket_client,
da6b8c20	30	struct batadv_icmp_header *icmph,
af4447f6	31	size_t icmp_len);
c6c8fea2	32
9039dc7e	33	void batadv_socket_init(void)
c6c8fea2	34	{
af4447f6	35	memset(batadv_socket_client_hash, 0, sizeof(batadv_socket_client_hash));
c6c8fea2 SE	36	}
c6c8fea2 SE	37
af4447f6	38	static int batadv_socket_open(struct inode inode, struct file file)
c6c8fea2 SE	39	{
c6c8fea2 SE	40	unsigned int i;
56303d34	41	struct batadv_socket_client *socket_client;
c6c8fea2	42
bd5b80d5 SE	43	if (!try_module_get(THIS_MODULE))
	44	return -EBUSY;
	45
c6c8fea2 SE	46	nonseekable_open(inode, file);
c6c8fea2 SE	47
704509b8	48	socket_client = kmalloc(sizeof(*socket_client), GFP_KERNEL);
bd5b80d5 SE	49	if (!socket_client) {
bd5b80d5 SE	50	module_put(THIS_MODULE);
c6c8fea2	51	return -ENOMEM;
bd5b80d5	52	}
c6c8fea2	53
af4447f6 SE	54	for (i = 0; i < ARRAY_SIZE(batadv_socket_client_hash); i++) {
	55	if (!batadv_socket_client_hash[i]) {
	56	batadv_socket_client_hash[i] = socket_client;
c6c8fea2 SE	57	break;
	58	}
	59	}
	60
af4447f6	61	if (i == ARRAY_SIZE(batadv_socket_client_hash)) {
86ceb360	62	pr_err("Error - can't add another packet client: maximum number of clients reached\n");
c6c8fea2	63	kfree(socket_client);
bd5b80d5	64	module_put(THIS_MODULE);
c6c8fea2 SE	65	return -EXFULL;
	66	}
	67
	68	INIT_LIST_HEAD(&socket_client->queue_list);
	69	socket_client->queue_len = 0;
	70	socket_client->index = i;
	71	socket_client->bat_priv = inode->i_private;
	72	spin_lock_init(&socket_client->lock);
	73	init_waitqueue_head(&socket_client->queue_wait);
	74
	75	file->private_data = socket_client;
	76
c6c8fea2 SE	77	return 0;
	78	}
	79
af4447f6	80	static int batadv_socket_release(struct inode inode, struct file file)
c6c8fea2	81	{
56303d34 SE	82	struct batadv_socket_client *socket_client = file->private_data;
56303d34 SE	83	struct batadv_socket_packet *socket_packet;
c6c8fea2 SE	84	struct list_head list_pos, list_pos_tmp;
	85
	86	spin_lock_bh(&socket_client->lock);
	87
	88	/* for all packets in the queue ... */
	89	list_for_each_safe(list_pos, list_pos_tmp, &socket_client->queue_list) {
	90	socket_packet = list_entry(list_pos,
56303d34	91	struct batadv_socket_packet, list);
c6c8fea2 SE	92
	93	list_del(list_pos);
	94	kfree(socket_packet);
	95	}
	96
af4447f6	97	batadv_socket_client_hash[socket_client->index] = NULL;
c6c8fea2 SE	98	spin_unlock_bh(&socket_client->lock);
	99
	100	kfree(socket_client);
bd5b80d5	101	module_put(THIS_MODULE);
c6c8fea2 SE	102
	103	return 0;
	104	}
	105
af4447f6 SE	106	static ssize_t batadv_socket_read(struct file file, char __user buf,
af4447f6 SE	107	size_t count, loff_t *ppos)
c6c8fea2	108	{
56303d34 SE	109	struct batadv_socket_client *socket_client = file->private_data;
56303d34 SE	110	struct batadv_socket_packet *socket_packet;
c6c8fea2 SE	111	size_t packet_len;
	112	int error;
	113
	114	if ((file->f_flags & O_NONBLOCK) && (socket_client->queue_len == 0))
	115	return -EAGAIN;
	116
96412690	117	if ((!buf) \|\| (count < sizeof(struct batadv_icmp_packet)))
c6c8fea2 SE	118	return -EINVAL;
	119
	120	if (!access_ok(VERIFY_WRITE, buf, count))
	121	return -EFAULT;
	122
	123	error = wait_event_interruptible(socket_client->queue_wait,
	124	socket_client->queue_len);
	125
	126	if (error)
	127	return error;
	128
	129	spin_lock_bh(&socket_client->lock);
	130
	131	socket_packet = list_first_entry(&socket_client->queue_list,
56303d34	132	struct batadv_socket_packet, list);
c6c8fea2 SE	133	list_del(&socket_packet->list);
	134	socket_client->queue_len--;
	135
	136	spin_unlock_bh(&socket_client->lock);
	137
b5a1eeef SE	138	packet_len = min(count, socket_packet->icmp_len);
b5a1eeef SE	139	error = copy_to_user(buf, &socket_packet->icmp_packet, packet_len);
c6c8fea2	140
c6c8fea2 SE	141	kfree(socket_packet);
	142
	143	if (error)
	144	return -EFAULT;
	145
	146	return packet_len;
	147	}
	148
af4447f6 SE	149	static ssize_t batadv_socket_write(struct file file, const char __user buff,
af4447f6 SE	150	size_t len, loff_t *off)
c6c8fea2	151	{
56303d34 SE	152	struct batadv_socket_client *socket_client = file->private_data;
	153	struct batadv_priv *bat_priv = socket_client->bat_priv;
	154	struct batadv_hard_iface *primary_if = NULL;
c6c8fea2	155	struct sk_buff *skb;
da6b8c20 SW	156	struct batadv_icmp_packet_rr *icmp_packet_rr;
da6b8c20 SW	157	struct batadv_icmp_header *icmp_header;
56303d34 SE	158	struct batadv_orig_node *orig_node = NULL;
56303d34 SE	159	struct batadv_neigh_node *neigh_node = NULL;
96412690	160	size_t packet_len = sizeof(struct batadv_icmp_packet);
c6c8fea2	161
da6b8c20	162	if (len < sizeof(struct batadv_icmp_header)) {
39c75a51	163	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1eda58bf	164	"Error - can't send packet from char device: invalid packet size\n");
c6c8fea2 SE	165	return -EINVAL;
	166	}
	167
e5d89254	168	primary_if = batadv_primary_if_get_selected(bat_priv);
32ae9b22 ML	169
	170	if (!primary_if) {
	171	len = -EFAULT;
	172	goto out;
	173	}
c6c8fea2	174
da6b8c20 SW	175	if (len >= BATADV_ICMP_MAX_PACKET_SIZE)
	176	packet_len = BATADV_ICMP_MAX_PACKET_SIZE;
	177	else
	178	packet_len = len;
c6c8fea2	179
41ab6c48	180	skb = netdev_alloc_skb_ip_align(NULL, packet_len + ETH_HLEN);
32ae9b22 ML	181	if (!skb) {
	182	len = -ENOMEM;
	183	goto out;
	184	}
c6c8fea2	185
c54f38c9	186	skb->priority = TC_PRIO_CONTROL;
41ab6c48	187	skb_reserve(skb, ETH_HLEN);
da6b8c20	188	icmp_header = (struct batadv_icmp_header *)skb_put(skb, packet_len);
c6c8fea2	189
da6b8c20	190	if (copy_from_user(icmp_header, buff, packet_len)) {
c6c8fea2 SE	191	len = -EFAULT;
	192	goto free_skb;
	193	}
	194
a40d9b07	195	if (icmp_header->packet_type != BATADV_ICMP) {
39c75a51	196	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1eda58bf	197	"Error - can't send packet from char device: got bogus packet type (expected: BAT_ICMP)\n");
c6c8fea2 SE	198	len = -EINVAL;
	199	goto free_skb;
	200	}
	201
da6b8c20 SW	202	switch (icmp_header->msg_type) {
	203	case BATADV_ECHO_REQUEST:
	204	if (len < sizeof(struct batadv_icmp_packet)) {
	205	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
	206	"Error - can't send packet from char device: invalid packet size\n");
	207	len = -EINVAL;
	208	goto free_skb;
	209	}
	210
	211	if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
	212	goto dst_unreach;
	213
	214	orig_node = batadv_orig_hash_find(bat_priv, icmp_header->dst);
	215	if (!orig_node)
	216	goto dst_unreach;
	217
7351a482 SW	218	neigh_node = batadv_orig_router_get(orig_node,
7351a482 SW	219	BATADV_IF_DEFAULT);
da6b8c20 SW	220	if (!neigh_node)
	221	goto dst_unreach;
	222
	223	if (!neigh_node->if_incoming)
	224	goto dst_unreach;
	225
	226	if (neigh_node->if_incoming->if_status != BATADV_IF_ACTIVE)
	227	goto dst_unreach;
	228
	229	icmp_packet_rr = (struct batadv_icmp_packet_rr *)icmp_header;
	230	if (packet_len == sizeof(*icmp_packet_rr))
	231	memcpy(icmp_packet_rr->rr,
	232	neigh_node->if_incoming->net_dev->dev_addr,
	233	ETH_ALEN);
	234
	235	break;
	236	default:
39c75a51	237	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
da6b8c20	238	"Error - can't send packet from char device: got unknown message type\n");
c6c8fea2 SE	239	len = -EINVAL;
	240	goto free_skb;
	241	}
	242
da6b8c20	243	icmp_header->uid = socket_client->index;
c6c8fea2	244
a40d9b07	245	if (icmp_header->version != BATADV_COMPAT_VERSION) {
da6b8c20	246	icmp_header->msg_type = BATADV_PARAMETER_PROBLEM;
a40d9b07	247	icmp_header->version = BATADV_COMPAT_VERSION;
da6b8c20	248	batadv_socket_add_packet(socket_client, icmp_header,
af4447f6	249	packet_len);
c6c8fea2 SE	250	goto free_skb;
	251	}
	252
da6b8c20	253	memcpy(icmp_header->orig, primary_if->net_dev->dev_addr, ETH_ALEN);
c6c8fea2	254
9455e34c	255	batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
c6c8fea2 SE	256	goto out;
c6c8fea2 SE	257
c6c8fea2	258	dst_unreach:
da6b8c20 SW	259	icmp_header->msg_type = BATADV_DESTINATION_UNREACHABLE;
da6b8c20 SW	260	batadv_socket_add_packet(socket_client, icmp_header, packet_len);
c6c8fea2 SE	261	free_skb:
	262	kfree_skb(skb);
	263	out:
32ae9b22	264	if (primary_if)
e5d89254	265	batadv_hardif_free_ref(primary_if);
44524fcd	266	if (neigh_node)
7d211efc	267	batadv_neigh_node_free_ref(neigh_node);
44524fcd	268	if (orig_node)
7d211efc	269	batadv_orig_node_free_ref(orig_node);
c6c8fea2 SE	270	return len;
	271	}
	272
af4447f6	273	static unsigned int batadv_socket_poll(struct file file, poll_table wait)
c6c8fea2	274	{
56303d34	275	struct batadv_socket_client *socket_client = file->private_data;
c6c8fea2 SE	276
	277	poll_wait(file, &socket_client->queue_wait, wait);
	278
	279	if (socket_client->queue_len > 0)
	280	return POLLIN \| POLLRDNORM;
	281
	282	return 0;
	283	}
	284
af4447f6	285	static const struct file_operations batadv_fops = {
c6c8fea2	286	.owner = THIS_MODULE,
af4447f6 SE	287	.open = batadv_socket_open,
	288	.release = batadv_socket_release,
	289	.read = batadv_socket_read,
	290	.write = batadv_socket_write,
	291	.poll = batadv_socket_poll,
c6c8fea2 SE	292	.llseek = no_llseek,
	293	};
	294
56303d34	295	int batadv_socket_setup(struct batadv_priv *bat_priv)
c6c8fea2 SE	296	{
	297	struct dentry *d;
	298
	299	if (!bat_priv->debug_dir)
	300	goto err;
	301
64346643	302	d = debugfs_create_file(BATADV_ICMP_SOCKET, S_IFREG \| S_IWUSR \| S_IRUSR,
af4447f6	303	bat_priv->debug_dir, bat_priv, &batadv_fops);
5346c35e	304	if (!d)
c6c8fea2 SE	305	goto err;
	306
	307	return 0;
	308
	309	err:
5346c35e	310	return -ENOMEM;
c6c8fea2 SE	311	}
c6c8fea2 SE	312
da6b8c20 SW	313	/**
	314	* batadv_socket_receive_packet - schedule an icmp packet to be sent to userspace
	315	* on an icmp socket.
	316	* @socket_client: the socket this packet belongs to
	317	* @icmph: pointer to the header of the icmp packet
	318	* @icmp_len: total length of the icmp packet
	319	*/
56303d34	320	static void batadv_socket_add_packet(struct batadv_socket_client *socket_client,
da6b8c20	321	struct batadv_icmp_header *icmph,
af4447f6	322	size_t icmp_len)
c6c8fea2	323	{
56303d34	324	struct batadv_socket_packet *socket_packet;
da6b8c20	325	size_t len;
c6c8fea2	326
704509b8	327	socket_packet = kmalloc(sizeof(*socket_packet), GFP_ATOMIC);
c6c8fea2 SE	328
	329	if (!socket_packet)
	330	return;
	331
da6b8c20 SW	332	len = icmp_len;
	333	/* check the maximum length before filling the buffer */
	334	if (len > sizeof(socket_packet->icmp_packet))
	335	len = sizeof(socket_packet->icmp_packet);
	336
c6c8fea2	337	INIT_LIST_HEAD(&socket_packet->list);
da6b8c20 SW	338	memcpy(&socket_packet->icmp_packet, icmph, len);
da6b8c20 SW	339	socket_packet->icmp_len = len;
c6c8fea2 SE	340
	341	spin_lock_bh(&socket_client->lock);
	342
	343	/* while waiting for the lock the socket_client could have been
9cfc7bd6 SE	344	* deleted
9cfc7bd6 SE	345	*/
da6b8c20	346	if (!batadv_socket_client_hash[icmph->uid]) {
c6c8fea2 SE	347	spin_unlock_bh(&socket_client->lock);
	348	kfree(socket_packet);
	349	return;
	350	}
	351
	352	list_add_tail(&socket_packet->list, &socket_client->queue_list);
	353	socket_client->queue_len++;
	354
	355	if (socket_client->queue_len > 100) {
	356	socket_packet = list_first_entry(&socket_client->queue_list,
56303d34 SE	357	struct batadv_socket_packet,
56303d34 SE	358	list);
c6c8fea2 SE	359
	360	list_del(&socket_packet->list);
	361	kfree(socket_packet);
	362	socket_client->queue_len--;
	363	}
	364
	365	spin_unlock_bh(&socket_client->lock);
	366
	367	wake_up(&socket_client->queue_wait);
	368	}
	369
da6b8c20 SW	370	/**
	371	* batadv_socket_receive_packet - schedule an icmp packet to be received
	372	* locally and sent to userspace.
	373	* @icmph: pointer to the header of the icmp packet
	374	* @icmp_len: total length of the icmp packet
	375	*/
	376	void batadv_socket_receive_packet(struct batadv_icmp_header *icmph,
9039dc7e	377	size_t icmp_len)
c6c8fea2	378	{
56303d34	379	struct batadv_socket_client *hash;
c6c8fea2	380
da6b8c20	381	hash = batadv_socket_client_hash[icmph->uid];
c6c8fea2	382	if (hash)
da6b8c20	383	batadv_socket_add_packet(hash, icmph, icmp_len);
c6c8fea2	384	}