[thirdparty/kernel/linux.git] / net / batman-adv / icmp_socket.c

// SPDX-License-Identifier: GPL-2.0
/* Copyright (C) 2007-2018  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/eventpoll.h>
#include <linux/export.h>
#include <linux/fcntl.h>
#include <linux/fs.h>
#include <linux/gfp.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/stddef.h>
#include <linux/string.h>
#include <linux/uaccess.h>
#include <linux/wait.h>
#include <uapi/linux/batadv_packet.h>

#include "debugfs.h"
#include "hard-interface.h"
#include "log.h"
#include "originator.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);

/**
 * batadv_socket_init() - Initialize soft interface independent socket data
 */
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;

	batadv_debugfs_deprecated(file, "");

	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(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 = 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 __poll_t 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 EPOLLIN | EPOLLRDNORM;

	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,
};

/**
 * batadv_socket_setup() - Create debugfs "socket" file
 * @bat_priv: the bat priv with all the soft interface information
 *
 * Return: 0 on success or negative error number in case of failure
 */
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, 0600, 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
7db7d9f3	1	// SPDX-License-Identifier: GPL-2.0
6b1aea8c	2	/* Copyright (C) 2007-2018 B.A.T.M.A.N. contributors:
c6c8fea2 SE	3	*
	4	* Marek Lindner
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of version 2 of the GNU General Public
	8	* License as published by the Free Software Foundation.
	9	*
	10	* This program is distributed in the hope that it will be useful, but
	11	* WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	13	* General Public License for more details.
	14	*
	15	* You should have received a copy of the GNU General Public License
ebf38fb7	16	* along with this program; if not, see <http://www.gnu.org/licenses/>.
c6c8fea2 SE	17	*/
c6c8fea2 SE	18
1e2c2a4f	19	#include "icmp_socket.h"
c6c8fea2	20	#include "main.h"
1e2c2a4f SE	21
	22	#include <linux/atomic.h>
	23	#include <linux/compiler.h>
c6c8fea2	24	#include <linux/debugfs.h>
1e2c2a4f SE	25	#include <linux/errno.h>
1e2c2a4f SE	26	#include <linux/etherdevice.h>
48881ed5	27	#include <linux/eventpoll.h>
1e2c2a4f SE	28	#include <linux/export.h>
	29	#include <linux/fcntl.h>
	30	#include <linux/fs.h>
b92b94ac	31	#include <linux/gfp.h>
1e2c2a4f SE	32	#include <linux/if_ether.h>
	33	#include <linux/kernel.h>
	34	#include <linux/list.h>
	35	#include <linux/module.h>
	36	#include <linux/netdevice.h>
	37	#include <linux/pkt_sched.h>
	38	#include <linux/poll.h>
	39	#include <linux/printk.h>
	40	#include <linux/sched.h> /* for linux/wait.h */
	41	#include <linux/skbuff.h>
c6c8fea2	42	#include <linux/slab.h>
1e2c2a4f	43	#include <linux/spinlock.h>
1e2c2a4f SE	44	#include <linux/stddef.h>
	45	#include <linux/string.h>
	46	#include <linux/uaccess.h>
	47	#include <linux/wait.h>
fec149f5	48	#include <uapi/linux/batadv_packet.h>
1e2c2a4f	49
00caf6a2	50	#include "debugfs.h"
c6c8fea2	51	#include "hard-interface.h"
ba412080	52	#include "log.h"
1e2c2a4f	53	#include "originator.h"
1e2c2a4f	54	#include "send.h"
c6c8fea2	55
56303d34	56	static struct batadv_socket_client *batadv_socket_client_hash[256];
c6c8fea2	57
56303d34	58	static void batadv_socket_add_packet(struct batadv_socket_client *socket_client,
da6b8c20	59	struct batadv_icmp_header *icmph,
af4447f6	60	size_t icmp_len);
c6c8fea2	61
ff15c27c SE	62	/**
	63	* batadv_socket_init() - Initialize soft interface independent socket data
	64	*/
9039dc7e	65	void batadv_socket_init(void)
c6c8fea2	66	{
af4447f6	67	memset(batadv_socket_client_hash, 0, sizeof(batadv_socket_client_hash));
c6c8fea2 SE	68	}
c6c8fea2 SE	69
af4447f6	70	static int batadv_socket_open(struct inode inode, struct file file)
c6c8fea2 SE	71	{
c6c8fea2 SE	72	unsigned int i;
56303d34	73	struct batadv_socket_client *socket_client;
c6c8fea2	74
bd5b80d5 SE	75	if (!try_module_get(THIS_MODULE))
	76	return -EBUSY;
	77
00caf6a2 SE	78	batadv_debugfs_deprecated(file, "");
00caf6a2 SE	79
c6c8fea2 SE	80	nonseekable_open(inode, file);
c6c8fea2 SE	81
704509b8	82	socket_client = kmalloc(sizeof(*socket_client), GFP_KERNEL);
bd5b80d5 SE	83	if (!socket_client) {
bd5b80d5 SE	84	module_put(THIS_MODULE);
c6c8fea2	85	return -ENOMEM;
bd5b80d5	86	}
c6c8fea2	87
af4447f6 SE	88	for (i = 0; i < ARRAY_SIZE(batadv_socket_client_hash); i++) {
	89	if (!batadv_socket_client_hash[i]) {
	90	batadv_socket_client_hash[i] = socket_client;
c6c8fea2 SE	91	break;
	92	}
	93	}
	94
af4447f6	95	if (i == ARRAY_SIZE(batadv_socket_client_hash)) {
86ceb360	96	pr_err("Error - can't add another packet client: maximum number of clients reached\n");
c6c8fea2	97	kfree(socket_client);
bd5b80d5	98	module_put(THIS_MODULE);
c6c8fea2 SE	99	return -EXFULL;
	100	}
	101
	102	INIT_LIST_HEAD(&socket_client->queue_list);
	103	socket_client->queue_len = 0;
	104	socket_client->index = i;
	105	socket_client->bat_priv = inode->i_private;
	106	spin_lock_init(&socket_client->lock);
	107	init_waitqueue_head(&socket_client->queue_wait);
	108
	109	file->private_data = socket_client;
	110
c6c8fea2 SE	111	return 0;
	112	}
	113
af4447f6	114	static int batadv_socket_release(struct inode inode, struct file file)
c6c8fea2	115	{
fb1f23ea GT	116	struct batadv_socket_client *client = file->private_data;
fb1f23ea GT	117	struct batadv_socket_packet packet, tmp;
c6c8fea2	118
fb1f23ea	119	spin_lock_bh(&client->lock);
c6c8fea2 SE	120
c6c8fea2 SE	121	/* for all packets in the queue ... */
fb1f23ea GT	122	list_for_each_entry_safe(packet, tmp, &client->queue_list, list) {
	123	list_del(&packet->list);
	124	kfree(packet);
c6c8fea2 SE	125	}
c6c8fea2 SE	126
fb1f23ea GT	127	batadv_socket_client_hash[client->index] = NULL;
fb1f23ea GT	128	spin_unlock_bh(&client->lock);
c6c8fea2	129
fb1f23ea	130	kfree(client);
bd5b80d5	131	module_put(THIS_MODULE);
c6c8fea2 SE	132
	133	return 0;
	134	}
	135
af4447f6 SE	136	static ssize_t batadv_socket_read(struct file file, char __user buf,
af4447f6 SE	137	size_t count, loff_t *ppos)
c6c8fea2	138	{
56303d34 SE	139	struct batadv_socket_client *socket_client = file->private_data;
56303d34 SE	140	struct batadv_socket_packet *socket_packet;
c6c8fea2 SE	141	size_t packet_len;
	142	int error;
	143
825ffe1f	144	if ((file->f_flags & O_NONBLOCK) && socket_client->queue_len == 0)
c6c8fea2 SE	145	return -EAGAIN;
c6c8fea2 SE	146
825ffe1f	147	if (!buf \|\| count < sizeof(struct batadv_icmp_packet))
c6c8fea2 SE	148	return -EINVAL;
c6c8fea2 SE	149
96d4f267	150	if (!access_ok(buf, count))
c6c8fea2 SE	151	return -EFAULT;
	152
	153	error = wait_event_interruptible(socket_client->queue_wait,
	154	socket_client->queue_len);
	155
	156	if (error)
	157	return error;
	158
	159	spin_lock_bh(&socket_client->lock);
	160
	161	socket_packet = list_first_entry(&socket_client->queue_list,
56303d34	162	struct batadv_socket_packet, list);
c6c8fea2 SE	163	list_del(&socket_packet->list);
	164	socket_client->queue_len--;
	165
	166	spin_unlock_bh(&socket_client->lock);
	167
b5a1eeef SE	168	packet_len = min(count, socket_packet->icmp_len);
b5a1eeef SE	169	error = copy_to_user(buf, &socket_packet->icmp_packet, packet_len);
c6c8fea2	170
c6c8fea2 SE	171	kfree(socket_packet);
	172
	173	if (error)
	174	return -EFAULT;
	175
	176	return packet_len;
	177	}
	178
af4447f6 SE	179	static ssize_t batadv_socket_write(struct file file, const char __user buff,
af4447f6 SE	180	size_t len, loff_t *off)
c6c8fea2	181	{
56303d34 SE	182	struct batadv_socket_client *socket_client = file->private_data;
	183	struct batadv_priv *bat_priv = socket_client->bat_priv;
	184	struct batadv_hard_iface *primary_if = NULL;
c6c8fea2	185	struct sk_buff *skb;
da6b8c20 SW	186	struct batadv_icmp_packet_rr *icmp_packet_rr;
da6b8c20 SW	187	struct batadv_icmp_header *icmp_header;
56303d34 SE	188	struct batadv_orig_node *orig_node = NULL;
56303d34 SE	189	struct batadv_neigh_node *neigh_node = NULL;
96412690	190	size_t packet_len = sizeof(struct batadv_icmp_packet);
6b5e971a	191	u8 *addr;
c6c8fea2	192
da6b8c20	193	if (len < sizeof(struct batadv_icmp_header)) {
39c75a51	194	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1eda58bf	195	"Error - can't send packet from char device: invalid packet size\n");
c6c8fea2 SE	196	return -EINVAL;
	197	}
	198
e5d89254	199	primary_if = batadv_primary_if_get_selected(bat_priv);
32ae9b22 ML	200
	201	if (!primary_if) {
	202	len = -EFAULT;
	203	goto out;
	204	}
c6c8fea2	205
da6b8c20 SW	206	if (len >= BATADV_ICMP_MAX_PACKET_SIZE)
	207	packet_len = BATADV_ICMP_MAX_PACKET_SIZE;
	208	else
	209	packet_len = len;
c6c8fea2	210
41ab6c48	211	skb = netdev_alloc_skb_ip_align(NULL, packet_len + ETH_HLEN);
32ae9b22 ML	212	if (!skb) {
	213	len = -ENOMEM;
	214	goto out;
	215	}
c6c8fea2	216
c54f38c9	217	skb->priority = TC_PRIO_CONTROL;
41ab6c48	218	skb_reserve(skb, ETH_HLEN);
4df864c1	219	icmp_header = skb_put(skb, packet_len);
c6c8fea2	220
da6b8c20	221	if (copy_from_user(icmp_header, buff, packet_len)) {
c6c8fea2 SE	222	len = -EFAULT;
	223	goto free_skb;
	224	}
	225
a40d9b07	226	if (icmp_header->packet_type != BATADV_ICMP) {
39c75a51	227	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
1eda58bf	228	"Error - can't send packet from char device: got bogus packet type (expected: BAT_ICMP)\n");
c6c8fea2 SE	229	len = -EINVAL;
	230	goto free_skb;
	231	}
	232
da6b8c20 SW	233	switch (icmp_header->msg_type) {
	234	case BATADV_ECHO_REQUEST:
	235	if (len < sizeof(struct batadv_icmp_packet)) {
	236	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
	237	"Error - can't send packet from char device: invalid packet size\n");
	238	len = -EINVAL;
	239	goto free_skb;
	240	}
	241
	242	if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
	243	goto dst_unreach;
	244
	245	orig_node = batadv_orig_hash_find(bat_priv, icmp_header->dst);
	246	if (!orig_node)
	247	goto dst_unreach;
	248
7351a482 SW	249	neigh_node = batadv_orig_router_get(orig_node,
7351a482 SW	250	BATADV_IF_DEFAULT);
da6b8c20 SW	251	if (!neigh_node)
	252	goto dst_unreach;
	253
	254	if (!neigh_node->if_incoming)
	255	goto dst_unreach;
	256
	257	if (neigh_node->if_incoming->if_status != BATADV_IF_ACTIVE)
	258	goto dst_unreach;
	259
	260	icmp_packet_rr = (struct batadv_icmp_packet_rr *)icmp_header;
8fdd0153 AQ	261	if (packet_len == sizeof(*icmp_packet_rr)) {
	262	addr = neigh_node->if_incoming->net_dev->dev_addr;
	263	ether_addr_copy(icmp_packet_rr->rr[0], addr);
	264	}
da6b8c20 SW	265
	266	break;
	267	default:
39c75a51	268	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
da6b8c20	269	"Error - can't send packet from char device: got unknown message type\n");
c6c8fea2 SE	270	len = -EINVAL;
	271	goto free_skb;
	272	}
	273
da6b8c20	274	icmp_header->uid = socket_client->index;
c6c8fea2	275
a40d9b07	276	if (icmp_header->version != BATADV_COMPAT_VERSION) {
da6b8c20	277	icmp_header->msg_type = BATADV_PARAMETER_PROBLEM;
a40d9b07	278	icmp_header->version = BATADV_COMPAT_VERSION;
da6b8c20	279	batadv_socket_add_packet(socket_client, icmp_header,
af4447f6	280	packet_len);
c6c8fea2 SE	281	goto free_skb;
	282	}
	283
8fdd0153	284	ether_addr_copy(icmp_header->orig, primary_if->net_dev->dev_addr);
c6c8fea2	285
95d39278	286	batadv_send_unicast_skb(skb, neigh_node);
c6c8fea2 SE	287	goto out;
c6c8fea2 SE	288
c6c8fea2	289	dst_unreach:
da6b8c20 SW	290	icmp_header->msg_type = BATADV_DESTINATION_UNREACHABLE;
da6b8c20 SW	291	batadv_socket_add_packet(socket_client, icmp_header, packet_len);
c6c8fea2 SE	292	free_skb:
	293	kfree_skb(skb);
	294	out:
32ae9b22	295	if (primary_if)
82047ad7	296	batadv_hardif_put(primary_if);
44524fcd	297	if (neigh_node)
25bb2509	298	batadv_neigh_node_put(neigh_node);
44524fcd	299	if (orig_node)
5d967310	300	batadv_orig_node_put(orig_node);
c6c8fea2 SE	301	return len;
	302	}
	303
ade994f4	304	static __poll_t batadv_socket_poll(struct file file, poll_table wait)
c6c8fea2	305	{
56303d34	306	struct batadv_socket_client *socket_client = file->private_data;
c6c8fea2 SE	307
	308	poll_wait(file, &socket_client->queue_wait, wait);
	309
	310	if (socket_client->queue_len > 0)
a9a08845	311	return EPOLLIN \| EPOLLRDNORM;
c6c8fea2 SE	312
	313	return 0;
	314	}
	315
af4447f6	316	static const struct file_operations batadv_fops = {
c6c8fea2	317	.owner = THIS_MODULE,
af4447f6 SE	318	.open = batadv_socket_open,
	319	.release = batadv_socket_release,
	320	.read = batadv_socket_read,
	321	.write = batadv_socket_write,
	322	.poll = batadv_socket_poll,
c6c8fea2 SE	323	.llseek = no_llseek,
	324	};
	325
ff15c27c SE	326	/**
	327	* batadv_socket_setup() - Create debugfs "socket" file
	328	* @bat_priv: the bat priv with all the soft interface information
	329	*
	330	* Return: 0 on success or negative error number in case of failure
	331	*/
56303d34	332	int batadv_socket_setup(struct batadv_priv *bat_priv)
c6c8fea2 SE	333	{
	334	struct dentry *d;
	335
	336	if (!bat_priv->debug_dir)
	337	goto err;
	338
507b37cf SE	339	d = debugfs_create_file(BATADV_ICMP_SOCKET, 0600, bat_priv->debug_dir,
507b37cf SE	340	bat_priv, &batadv_fops);
5346c35e	341	if (!d)
c6c8fea2 SE	342	goto err;
	343
	344	return 0;
	345
	346	err:
5346c35e	347	return -ENOMEM;
c6c8fea2 SE	348	}
c6c8fea2 SE	349
da6b8c20	350	/**
7e9a8c2c	351	* batadv_socket_add_packet() - schedule an icmp packet to be sent to
34473822	352	* userspace on an icmp socket.
da6b8c20 SW	353	* @socket_client: the socket this packet belongs to
	354	* @icmph: pointer to the header of the icmp packet
	355	* @icmp_len: total length of the icmp packet
	356	*/
56303d34	357	static void batadv_socket_add_packet(struct batadv_socket_client *socket_client,
da6b8c20	358	struct batadv_icmp_header *icmph,
af4447f6	359	size_t icmp_len)
c6c8fea2	360	{
56303d34	361	struct batadv_socket_packet *socket_packet;
da6b8c20	362	size_t len;
c6c8fea2	363
704509b8	364	socket_packet = kmalloc(sizeof(*socket_packet), GFP_ATOMIC);
c6c8fea2 SE	365
	366	if (!socket_packet)
	367	return;
	368
da6b8c20 SW	369	len = icmp_len;
	370	/* check the maximum length before filling the buffer */
	371	if (len > sizeof(socket_packet->icmp_packet))
	372	len = sizeof(socket_packet->icmp_packet);
	373
c6c8fea2	374	INIT_LIST_HEAD(&socket_packet->list);
da6b8c20 SW	375	memcpy(&socket_packet->icmp_packet, icmph, len);
da6b8c20 SW	376	socket_packet->icmp_len = len;
c6c8fea2 SE	377
	378	spin_lock_bh(&socket_client->lock);
	379
	380	/* while waiting for the lock the socket_client could have been
9cfc7bd6 SE	381	* deleted
9cfc7bd6 SE	382	*/
da6b8c20	383	if (!batadv_socket_client_hash[icmph->uid]) {
c6c8fea2 SE	384	spin_unlock_bh(&socket_client->lock);
	385	kfree(socket_packet);
	386	return;
	387	}
	388
	389	list_add_tail(&socket_packet->list, &socket_client->queue_list);
	390	socket_client->queue_len++;
	391
	392	if (socket_client->queue_len > 100) {
	393	socket_packet = list_first_entry(&socket_client->queue_list,
56303d34 SE	394	struct batadv_socket_packet,
56303d34 SE	395	list);
c6c8fea2 SE	396
	397	list_del(&socket_packet->list);
	398	kfree(socket_packet);
	399	socket_client->queue_len--;
	400	}
	401
	402	spin_unlock_bh(&socket_client->lock);
	403
	404	wake_up(&socket_client->queue_wait);
	405	}
	406
da6b8c20	407	/**
7e9a8c2c	408	* batadv_socket_receive_packet() - schedule an icmp packet to be received
da6b8c20 SW	409	* locally and sent to userspace.
	410	* @icmph: pointer to the header of the icmp packet
	411	* @icmp_len: total length of the icmp packet
	412	*/
	413	void batadv_socket_receive_packet(struct batadv_icmp_header *icmph,
9039dc7e	414	size_t icmp_len)
c6c8fea2	415	{
56303d34	416	struct batadv_socket_client *hash;
c6c8fea2	417
da6b8c20	418	hash = batadv_socket_client_hash[icmph->uid];
c6c8fea2	419	if (hash)
da6b8c20	420	batadv_socket_add_packet(hash, icmph, icmp_len);
c6c8fea2	421	}