[mirror_ubuntu-zesty-kernel.git] / net / batman-adv / icmp_socket.c

/* Copyright (C) 2007-2016  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 "icmp_socket.h"
#include "main.h"

#include <linux/atomic.h>
#include <linux/compiler.h>
#include <linux/debugfs.h>
#include <linux/errno.h>
#include <linux/etherdevice.h>
#include <linux/export.h>
#include <linux/fcntl.h>
#include <linux/fs.h>
#include <linux/if_ether.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/pkt_sched.h>
#include <linux/poll.h>
#include <linux/printk.h>
#include <linux/sched.h> /* for linux/wait.h */
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/stat.h>
#include <linux/stddef.h>
#include <linux/string.h>
#include <linux/uaccess.h>
#include <linux/wait.h>

#include "hard-interface.h"
#include "log.h"
#include "originator.h"
#include "packet.h"
#include "send.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 *client = file->private_data;
	struct batadv_socket_packet *packet, *tmp;

	spin_lock_bh(&client->lock);

	/* for all packets in the queue ... */
	list_for_each_entry_safe(packet, tmp, &client->queue_list, list) {
		list_del(&packet->list);
		kfree(packet);
	}

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

	kfree(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);
	u8 *addr;

	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)) {
			addr = neigh_node->if_incoming->net_dev->dev_addr;
			ether_addr_copy(icmp_packet_rr->rr[0], addr);
		}

		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;
	}

	ether_addr_copy(icmp_header->orig, primary_if->net_dev->dev_addr);

	batadv_send_unicast_skb(skb, neigh_node);
	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_put(primary_if);
	if (neigh_node)
		batadv_neigh_node_put(neigh_node);
	if (orig_node)
		batadv_orig_node_put(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_add_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
0046b040	1	/* Copyright (C) 2007-2016 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	*/
c6c8fea2 SE	17
1e2c2a4f	18	#include "icmp_socket.h"
c6c8fea2	19	#include "main.h"
1e2c2a4f SE	20
	21	#include <linux/atomic.h>
	22	#include <linux/compiler.h>
c6c8fea2	23	#include <linux/debugfs.h>
1e2c2a4f SE	24	#include <linux/errno.h>
	25	#include <linux/etherdevice.h>
	26	#include <linux/export.h>
	27	#include <linux/fcntl.h>
	28	#include <linux/fs.h>
	29	#include <linux/if_ether.h>
	30	#include <linux/kernel.h>
	31	#include <linux/list.h>
	32	#include <linux/module.h>
	33	#include <linux/netdevice.h>
	34	#include <linux/pkt_sched.h>
	35	#include <linux/poll.h>
	36	#include <linux/printk.h>
	37	#include <linux/sched.h> /* for linux/wait.h */
	38	#include <linux/skbuff.h>
c6c8fea2	39	#include <linux/slab.h>
1e2c2a4f SE	40	#include <linux/spinlock.h>
	41	#include <linux/stat.h>
	42	#include <linux/stddef.h>
	43	#include <linux/string.h>
	44	#include <linux/uaccess.h>
	45	#include <linux/wait.h>
	46
c6c8fea2	47	#include "hard-interface.h"
ba412080	48	#include "log.h"
1e2c2a4f SE	49	#include "originator.h"
	50	#include "packet.h"
	51	#include "send.h"
c6c8fea2	52
56303d34	53	static struct batadv_socket_client *batadv_socket_client_hash[256];
c6c8fea2	54
56303d34	55	static void batadv_socket_add_packet(struct batadv_socket_client *socket_client,
da6b8c20	56	struct batadv_icmp_header *icmph,
af4447f6	57	size_t icmp_len);
c6c8fea2	58
9039dc7e	59	void batadv_socket_init(void)
c6c8fea2	60	{
af4447f6	61	memset(batadv_socket_client_hash, 0, sizeof(batadv_socket_client_hash));
c6c8fea2 SE	62	}
c6c8fea2 SE	63
af4447f6	64	static int batadv_socket_open(struct inode inode, struct file file)
c6c8fea2 SE	65	{
c6c8fea2 SE	66	unsigned int i;
56303d34	67	struct batadv_socket_client *socket_client;
c6c8fea2	68
bd5b80d5 SE	69	if (!try_module_get(THIS_MODULE))
	70	return -EBUSY;
	71
c6c8fea2 SE	72	nonseekable_open(inode, file);
c6c8fea2 SE	73
704509b8	74	socket_client = kmalloc(sizeof(*socket_client), GFP_KERNEL);
bd5b80d5 SE	75	if (!socket_client) {
bd5b80d5 SE	76	module_put(THIS_MODULE);
c6c8fea2	77	return -ENOMEM;
bd5b80d5	78	}
c6c8fea2	79
af4447f6 SE	80	for (i = 0; i < ARRAY_SIZE(batadv_socket_client_hash); i++) {
	81	if (!batadv_socket_client_hash[i]) {
	82	batadv_socket_client_hash[i] = socket_client;
c6c8fea2 SE	83	break;
	84	}
	85	}
	86
af4447f6	87	if (i == ARRAY_SIZE(batadv_socket_client_hash)) {
86ceb360	88	pr_err("Error - can't add another packet client: maximum number of clients reached\n");
c6c8fea2	89	kfree(socket_client);
bd5b80d5	90	module_put(THIS_MODULE);
c6c8fea2 SE	91	return -EXFULL;
	92	}
	93
	94	INIT_LIST_HEAD(&socket_client->queue_list);
	95	socket_client->queue_len = 0;
	96	socket_client->index = i;
	97	socket_client->bat_priv = inode->i_private;
	98	spin_lock_init(&socket_client->lock);
	99	init_waitqueue_head(&socket_client->queue_wait);
	100
	101	file->private_data = socket_client;
	102
c6c8fea2 SE	103	return 0;
	104	}
	105
af4447f6	106	static int batadv_socket_release(struct inode inode, struct file file)
c6c8fea2	107	{
fb1f23ea GT	108	struct batadv_socket_client *client = file->private_data;
fb1f23ea GT	109	struct batadv_socket_packet packet, tmp;
c6c8fea2	110
fb1f23ea	111	spin_lock_bh(&client->lock);
c6c8fea2 SE	112
c6c8fea2 SE	113	/* for all packets in the queue ... */
fb1f23ea GT	114	list_for_each_entry_safe(packet, tmp, &client->queue_list, list) {
	115	list_del(&packet->list);
	116	kfree(packet);
c6c8fea2 SE	117	}
c6c8fea2 SE	118
fb1f23ea GT	119	batadv_socket_client_hash[client->index] = NULL;
fb1f23ea GT	120	spin_unlock_bh(&client->lock);
c6c8fea2	121
fb1f23ea	122	kfree(client);
bd5b80d5	123	module_put(THIS_MODULE);
c6c8fea2 SE	124
	125	return 0;
	126	}
	127
af4447f6 SE	128	static ssize_t batadv_socket_read(struct file file, char __user buf,
af4447f6 SE	129	size_t count, loff_t *ppos)
c6c8fea2	130	{
56303d34 SE	131	struct batadv_socket_client *socket_client = file->private_data;
56303d34 SE	132	struct batadv_socket_packet *socket_packet;
c6c8fea2 SE	133	size_t packet_len;
	134	int error;
	135
	136	if ((file->f_flags & O_NONBLOCK) && (socket_client->queue_len == 0))
	137	return -EAGAIN;
	138
96412690	139	if ((!buf) \|\| (count < sizeof(struct batadv_icmp_packet)))
c6c8fea2 SE	140	return -EINVAL;
	141
	142	if (!access_ok(VERIFY_WRITE, buf, count))
	143	return -EFAULT;
	144
	145	error = wait_event_interruptible(socket_client->queue_wait,
	146	socket_client->queue_len);
	147
	148	if (error)
	149	return error;
	150
	151	spin_lock_bh(&socket_client->lock);
	152
	153	socket_packet = list_first_entry(&socket_client->queue_list,
56303d34	154	struct batadv_socket_packet, list);
c6c8fea2 SE	155	list_del(&socket_packet->list);
	156	socket_client->queue_len--;
	157
	158	spin_unlock_bh(&socket_client->lock);
	159
b5a1eeef SE	160	packet_len = min(count, socket_packet->icmp_len);
b5a1eeef SE	161	error = copy_to_user(buf, &socket_packet->icmp_packet, packet_len);
c6c8fea2	162
c6c8fea2 SE	163	kfree(socket_packet);
	164
	165	if (error)
	166	return -EFAULT;
	167
	168	return packet_len;
	169	}
	170
af4447f6 SE	171	static ssize_t batadv_socket_write(struct file file, const char __user buff,
af4447f6 SE	172	size_t len, loff_t *off)
c6c8fea2	173	{
56303d34 SE	174	struct batadv_socket_client *socket_client = file->private_data;
	175	struct batadv_priv *bat_priv = socket_client->bat_priv;
	176	struct batadv_hard_iface *primary_if = NULL;
c6c8fea2	177	struct sk_buff *skb;
da6b8c20 SW	178	struct batadv_icmp_packet_rr *icmp_packet_rr;
da6b8c20 SW	179	struct batadv_icmp_header *icmp_header;
56303d34 SE	180	struct batadv_orig_node *orig_node = NULL;
56303d34 SE	181	struct batadv_neigh_node *neigh_node = NULL;
96412690	182	size_t packet_len = sizeof(struct batadv_icmp_packet);
6b5e971a	183	u8 *addr;
c6c8fea2	184
da6b8c20	185	if (len < sizeof(struct batadv_icmp_header)) {
39c75a51	186	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1eda58bf	187	"Error - can't send packet from char device: invalid packet size\n");
c6c8fea2 SE	188	return -EINVAL;
	189	}
	190
e5d89254	191	primary_if = batadv_primary_if_get_selected(bat_priv);
32ae9b22 ML	192
	193	if (!primary_if) {
	194	len = -EFAULT;
	195	goto out;
	196	}
c6c8fea2	197
da6b8c20 SW	198	if (len >= BATADV_ICMP_MAX_PACKET_SIZE)
	199	packet_len = BATADV_ICMP_MAX_PACKET_SIZE;
	200	else
	201	packet_len = len;
c6c8fea2	202
41ab6c48	203	skb = netdev_alloc_skb_ip_align(NULL, packet_len + ETH_HLEN);
32ae9b22 ML	204	if (!skb) {
	205	len = -ENOMEM;
	206	goto out;
	207	}
c6c8fea2	208
c54f38c9	209	skb->priority = TC_PRIO_CONTROL;
41ab6c48	210	skb_reserve(skb, ETH_HLEN);
da6b8c20	211	icmp_header = (struct batadv_icmp_header *)skb_put(skb, packet_len);
c6c8fea2	212
da6b8c20	213	if (copy_from_user(icmp_header, buff, packet_len)) {
c6c8fea2 SE	214	len = -EFAULT;
	215	goto free_skb;
	216	}
	217
a40d9b07	218	if (icmp_header->packet_type != BATADV_ICMP) {
39c75a51	219	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1eda58bf	220	"Error - can't send packet from char device: got bogus packet type (expected: BAT_ICMP)\n");
c6c8fea2 SE	221	len = -EINVAL;
	222	goto free_skb;
	223	}
	224
da6b8c20 SW	225	switch (icmp_header->msg_type) {
	226	case BATADV_ECHO_REQUEST:
	227	if (len < sizeof(struct batadv_icmp_packet)) {
	228	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
	229	"Error - can't send packet from char device: invalid packet size\n");
	230	len = -EINVAL;
	231	goto free_skb;
	232	}
	233
	234	if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
	235	goto dst_unreach;
	236
	237	orig_node = batadv_orig_hash_find(bat_priv, icmp_header->dst);
	238	if (!orig_node)
	239	goto dst_unreach;
	240
7351a482 SW	241	neigh_node = batadv_orig_router_get(orig_node,
7351a482 SW	242	BATADV_IF_DEFAULT);
da6b8c20 SW	243	if (!neigh_node)
	244	goto dst_unreach;
	245
	246	if (!neigh_node->if_incoming)
	247	goto dst_unreach;
	248
	249	if (neigh_node->if_incoming->if_status != BATADV_IF_ACTIVE)
	250	goto dst_unreach;
	251
	252	icmp_packet_rr = (struct batadv_icmp_packet_rr *)icmp_header;
8fdd0153 AQ	253	if (packet_len == sizeof(*icmp_packet_rr)) {
	254	addr = neigh_node->if_incoming->net_dev->dev_addr;
	255	ether_addr_copy(icmp_packet_rr->rr[0], addr);
	256	}
da6b8c20 SW	257
	258	break;
	259	default:
39c75a51	260	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
da6b8c20	261	"Error - can't send packet from char device: got unknown message type\n");
c6c8fea2 SE	262	len = -EINVAL;
	263	goto free_skb;
	264	}
	265
da6b8c20	266	icmp_header->uid = socket_client->index;
c6c8fea2	267
a40d9b07	268	if (icmp_header->version != BATADV_COMPAT_VERSION) {
da6b8c20	269	icmp_header->msg_type = BATADV_PARAMETER_PROBLEM;
a40d9b07	270	icmp_header->version = BATADV_COMPAT_VERSION;
da6b8c20	271	batadv_socket_add_packet(socket_client, icmp_header,
af4447f6	272	packet_len);
c6c8fea2 SE	273	goto free_skb;
	274	}
	275
8fdd0153	276	ether_addr_copy(icmp_header->orig, primary_if->net_dev->dev_addr);
c6c8fea2	277
95d39278	278	batadv_send_unicast_skb(skb, neigh_node);
c6c8fea2 SE	279	goto out;
c6c8fea2 SE	280
c6c8fea2	281	dst_unreach:
da6b8c20 SW	282	icmp_header->msg_type = BATADV_DESTINATION_UNREACHABLE;
da6b8c20 SW	283	batadv_socket_add_packet(socket_client, icmp_header, packet_len);
c6c8fea2 SE	284	free_skb:
	285	kfree_skb(skb);
	286	out:
32ae9b22	287	if (primary_if)
82047ad7	288	batadv_hardif_put(primary_if);
44524fcd	289	if (neigh_node)
25bb2509	290	batadv_neigh_node_put(neigh_node);
44524fcd	291	if (orig_node)
5d967310	292	batadv_orig_node_put(orig_node);
c6c8fea2 SE	293	return len;
	294	}
	295
af4447f6	296	static unsigned int batadv_socket_poll(struct file file, poll_table wait)
c6c8fea2	297	{
56303d34	298	struct batadv_socket_client *socket_client = file->private_data;
c6c8fea2 SE	299
	300	poll_wait(file, &socket_client->queue_wait, wait);
	301
	302	if (socket_client->queue_len > 0)
	303	return POLLIN \| POLLRDNORM;
	304
	305	return 0;
	306	}
	307
af4447f6	308	static const struct file_operations batadv_fops = {
c6c8fea2	309	.owner = THIS_MODULE,
af4447f6 SE	310	.open = batadv_socket_open,
	311	.release = batadv_socket_release,
	312	.read = batadv_socket_read,
	313	.write = batadv_socket_write,
	314	.poll = batadv_socket_poll,
c6c8fea2 SE	315	.llseek = no_llseek,
	316	};
	317
56303d34	318	int batadv_socket_setup(struct batadv_priv *bat_priv)
c6c8fea2 SE	319	{
	320	struct dentry *d;
	321
	322	if (!bat_priv->debug_dir)
	323	goto err;
	324
64346643	325	d = debugfs_create_file(BATADV_ICMP_SOCKET, S_IFREG \| S_IWUSR \| S_IRUSR,
af4447f6	326	bat_priv->debug_dir, bat_priv, &batadv_fops);
5346c35e	327	if (!d)
c6c8fea2 SE	328	goto err;
	329
	330	return 0;
	331
	332	err:
5346c35e	333	return -ENOMEM;
c6c8fea2 SE	334	}
c6c8fea2 SE	335
da6b8c20	336	/**
6d030de8	337	* batadv_socket_add_packet - schedule an icmp packet to be sent to
34473822	338	* userspace on an icmp socket.
da6b8c20 SW	339	* @socket_client: the socket this packet belongs to
	340	* @icmph: pointer to the header of the icmp packet
	341	* @icmp_len: total length of the icmp packet
	342	*/
56303d34	343	static void batadv_socket_add_packet(struct batadv_socket_client *socket_client,
da6b8c20	344	struct batadv_icmp_header *icmph,
af4447f6	345	size_t icmp_len)
c6c8fea2	346	{
56303d34	347	struct batadv_socket_packet *socket_packet;
da6b8c20	348	size_t len;
c6c8fea2	349
704509b8	350	socket_packet = kmalloc(sizeof(*socket_packet), GFP_ATOMIC);
c6c8fea2 SE	351
	352	if (!socket_packet)
	353	return;
	354
da6b8c20 SW	355	len = icmp_len;
	356	/* check the maximum length before filling the buffer */
	357	if (len > sizeof(socket_packet->icmp_packet))
	358	len = sizeof(socket_packet->icmp_packet);
	359
c6c8fea2	360	INIT_LIST_HEAD(&socket_packet->list);
da6b8c20 SW	361	memcpy(&socket_packet->icmp_packet, icmph, len);
da6b8c20 SW	362	socket_packet->icmp_len = len;
c6c8fea2 SE	363
	364	spin_lock_bh(&socket_client->lock);
	365
	366	/* while waiting for the lock the socket_client could have been
9cfc7bd6 SE	367	* deleted
9cfc7bd6 SE	368	*/
da6b8c20	369	if (!batadv_socket_client_hash[icmph->uid]) {
c6c8fea2 SE	370	spin_unlock_bh(&socket_client->lock);
	371	kfree(socket_packet);
	372	return;
	373	}
	374
	375	list_add_tail(&socket_packet->list, &socket_client->queue_list);
	376	socket_client->queue_len++;
	377
	378	if (socket_client->queue_len > 100) {
	379	socket_packet = list_first_entry(&socket_client->queue_list,
56303d34 SE	380	struct batadv_socket_packet,
56303d34 SE	381	list);
c6c8fea2 SE	382
	383	list_del(&socket_packet->list);
	384	kfree(socket_packet);
	385	socket_client->queue_len--;
	386	}
	387
	388	spin_unlock_bh(&socket_client->lock);
	389
	390	wake_up(&socket_client->queue_wait);
	391	}
	392
da6b8c20 SW	393	/**
	394	* batadv_socket_receive_packet - schedule an icmp packet to be received
	395	* locally and sent to userspace.
	396	* @icmph: pointer to the header of the icmp packet
	397	* @icmp_len: total length of the icmp packet
	398	*/
	399	void batadv_socket_receive_packet(struct batadv_icmp_header *icmph,
9039dc7e	400	size_t icmp_len)
c6c8fea2	401	{
56303d34	402	struct batadv_socket_client *hash;
c6c8fea2	403
da6b8c20	404	hash = batadv_socket_client_hash[icmph->uid];
c6c8fea2	405	if (hash)
da6b8c20	406	batadv_socket_add_packet(hash, icmph, icmp_len);
c6c8fea2	407	}