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

/*
 * Copyright (C) 2007-2011 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 socket_client *socket_client_hash[256];

static void bat_socket_add_packet(struct socket_client *socket_client,
				  struct icmp_packet_rr *icmp_packet,
				  size_t icmp_len);

void bat_socket_init(void)
{
	memset(socket_client_hash, 0, sizeof(socket_client_hash));
}

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

	nonseekable_open(inode, file);

	socket_client = kmalloc(sizeof(struct socket_client), GFP_KERNEL);

	if (!socket_client)
		return -ENOMEM;

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

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

	inc_module_count();
	return 0;
}

static int bat_socket_release(struct inode *inode, struct file *file)
{
	struct socket_client *socket_client = file->private_data;
	struct 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 socket_packet, list);

		list_del(list_pos);
		kfree(socket_packet);
	}

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

	kfree(socket_client);
	dec_module_count();

	return 0;
}

static ssize_t bat_socket_read(struct file *file, char __user *buf,
			       size_t count, loff_t *ppos)
{
	struct socket_client *socket_client = file->private_data;
	struct 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 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 socket_packet, list);
	list_del(&socket_packet->list);
	socket_client->queue_len--;

	spin_unlock_bh(&socket_client->lock);

	error = __copy_to_user(buf, &socket_packet->icmp_packet,
			       socket_packet->icmp_len);

	packet_len = socket_packet->icmp_len;
	kfree(socket_packet);

	if (error)
		return -EFAULT;

	return packet_len;
}

static ssize_t bat_socket_write(struct file *file, const char __user *buff,
				size_t len, loff_t *off)
{
	struct socket_client *socket_client = file->private_data;
	struct bat_priv *bat_priv = socket_client->bat_priv;
	struct sk_buff *skb;
	struct icmp_packet_rr *icmp_packet;

	struct orig_node *orig_node = NULL;
	struct neigh_node *neigh_node = NULL;
	size_t packet_len = sizeof(struct icmp_packet);

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

	if (!bat_priv->primary_if)
		return -EFAULT;

	if (len >= sizeof(struct icmp_packet_rr))
		packet_len = sizeof(struct icmp_packet_rr);

	skb = dev_alloc_skb(packet_len + sizeof(struct ethhdr));
	if (!skb)
		return -ENOMEM;

	skb_reserve(skb, sizeof(struct ethhdr));
	icmp_packet = (struct icmp_packet_rr *)skb_put(skb, packet_len);

	if (!access_ok(VERIFY_READ, buff, packet_len)) {
		len = -EFAULT;
		goto free_skb;
	}

	if (__copy_from_user(icmp_packet, buff, packet_len)) {
		len = -EFAULT;
		goto free_skb;
	}

	if (icmp_packet->packet_type != BAT_ICMP) {
		bat_dbg(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;
	}

	if (icmp_packet->msg_type != ECHO_REQUEST) {
		bat_dbg(DBG_BATMAN, bat_priv,
			"Error - can't send packet from char device: "
			"got bogus message type (expected: ECHO_REQUEST)\n");
		len = -EINVAL;
		goto free_skb;
	}

	icmp_packet->uid = socket_client->index;

	if (icmp_packet->version != COMPAT_VERSION) {
		icmp_packet->msg_type = PARAMETER_PROBLEM;
		icmp_packet->ttl = COMPAT_VERSION;
		bat_socket_add_packet(socket_client, icmp_packet, packet_len);
		goto free_skb;
	}

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

	rcu_read_lock();
	orig_node = orig_hash_find(bat_priv, icmp_packet->dst);

	if (!orig_node)
		goto unlock;

	neigh_node = orig_node->router;

	if (!neigh_node)
		goto unlock;

	if (!atomic_inc_not_zero(&neigh_node->refcount)) {
		neigh_node = NULL;
		goto unlock;
	}

	rcu_read_unlock();

	if (!neigh_node->if_incoming)
		goto dst_unreach;

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

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

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

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

unlock:
	rcu_read_unlock();
dst_unreach:
	icmp_packet->msg_type = DESTINATION_UNREACHABLE;
	bat_socket_add_packet(socket_client, icmp_packet, packet_len);
free_skb:
	kfree_skb(skb);
out:
	if (neigh_node)
		neigh_node_free_ref(neigh_node);
	if (orig_node)
		orig_node_free_ref(orig_node);
	return len;
}

static unsigned int bat_socket_poll(struct file *file, poll_table *wait)
{
	struct 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 fops = {
	.owner = THIS_MODULE,
	.open = bat_socket_open,
	.release = bat_socket_release,
	.read = bat_socket_read,
	.write = bat_socket_write,
	.poll = bat_socket_poll,
	.llseek = no_llseek,
};

int bat_socket_setup(struct bat_priv *bat_priv)
{
	struct dentry *d;

	if (!bat_priv->debug_dir)
		goto err;

	d = debugfs_create_file(ICMP_SOCKET, S_IFREG | S_IWUSR | S_IRUSR,
				bat_priv->debug_dir, bat_priv, &fops);
	if (d)
		goto err;

	return 0;

err:
	return 1;
}

static void bat_socket_add_packet(struct socket_client *socket_client,
				  struct icmp_packet_rr *icmp_packet,
				  size_t icmp_len)
{
	struct socket_packet *socket_packet;

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

	if (!socket_packet)
		return;

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

	spin_lock_bh(&socket_client->lock);

	/* while waiting for the lock the socket_client could have been
	 * deleted */
	if (!socket_client_hash[icmp_packet->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 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);
}

void bat_socket_receive_packet(struct icmp_packet_rr *icmp_packet,
			       size_t icmp_len)
{
	struct socket_client *hash = socket_client_hash[icmp_packet->uid];

	if (hash)
		bat_socket_add_packet(hash, icmp_packet, icmp_len);
}
Commit	Line	Data
c6c8fea2	1	/*
64afe353	2	* Copyright (C) 2007-2011 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
	16	* along with this program; if not, write to the Free Software
	17	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
	18	* 02110-1301, USA
	19	*
	20	*/
	21
	22	#include "main.h"
	23	#include <linux/debugfs.h>
	24	#include <linux/slab.h>
	25	#include "icmp_socket.h"
	26	#include "send.h"
c6c8fea2 SE	27	#include "hash.h"
	28	#include "originator.h"
	29	#include "hard-interface.h"
	30
	31	static struct socket_client *socket_client_hash[256];
	32
	33	static void bat_socket_add_packet(struct socket_client *socket_client,
	34	struct icmp_packet_rr *icmp_packet,
	35	size_t icmp_len);
	36
	37	void bat_socket_init(void)
	38	{
	39	memset(socket_client_hash, 0, sizeof(socket_client_hash));
	40	}
	41
	42	static int bat_socket_open(struct inode inode, struct file file)
	43	{
	44	unsigned int i;
	45	struct socket_client *socket_client;
	46
	47	nonseekable_open(inode, file);
	48
	49	socket_client = kmalloc(sizeof(struct socket_client), GFP_KERNEL);
	50
	51	if (!socket_client)
	52	return -ENOMEM;
	53
	54	for (i = 0; i < ARRAY_SIZE(socket_client_hash); i++) {
	55	if (!socket_client_hash[i]) {
	56	socket_client_hash[i] = socket_client;
	57	break;
	58	}
	59	}
	60
	61	if (i == ARRAY_SIZE(socket_client_hash)) {
	62	pr_err("Error - can't add another packet client: "
	63	"maximum number of clients reached\n");
	64	kfree(socket_client);
	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
	77	inc_module_count();
	78	return 0;
	79	}
	80
	81	static int bat_socket_release(struct inode inode, struct file file)
	82	{
	83	struct socket_client *socket_client = file->private_data;
	84	struct socket_packet *socket_packet;
	85	struct list_head list_pos, list_pos_tmp;
	86
	87	spin_lock_bh(&socket_client->lock);
	88
	89	/* for all packets in the queue ... */
	90	list_for_each_safe(list_pos, list_pos_tmp, &socket_client->queue_list) {
91	socket_packet = list_entry(list_pos,
92	struct socket_packet, list);
93
94	list_del(list_pos);
95	kfree(socket_packet);
96	}
97
98	socket_client_hash[socket_client->index] = NULL;
99	spin_unlock_bh(&socket_client->lock);
100
101	kfree(socket_client);
102	dec_module_count();
103
104	return 0;
105	}
106
107	static ssize_t bat_socket_read(struct file file, char __user buf,
108	size_t count, loff_t *ppos)
109	{
110	struct socket_client *socket_client = file->private_data;
111	struct socket_packet *socket_packet;
112	size_t packet_len;
113	int error;
114
115	if ((file->f_flags & O_NONBLOCK) && (socket_client->queue_len == 0))
116	return -EAGAIN;
117
118	if ((!buf) \|\| (count < sizeof(struct icmp_packet)))
119	return -EINVAL;
120
121	if (!access_ok(VERIFY_WRITE, buf, count))
122	return -EFAULT;
123
124	error = wait_event_interruptible(socket_client->queue_wait,
125	socket_client->queue_len);
126
127	if (error)
128	return error;
129
130	spin_lock_bh(&socket_client->lock);
131
132	socket_packet = list_first_entry(&socket_client->queue_list,
133	struct socket_packet, list);
134	list_del(&socket_packet->list);
135	socket_client->queue_len--;
136
137	spin_unlock_bh(&socket_client->lock);
138
139	error = __copy_to_user(buf, &socket_packet->icmp_packet,
140	socket_packet->icmp_len);
141
142	packet_len = socket_packet->icmp_len;
143	kfree(socket_packet);
144
145	if (error)
146	return -EFAULT;
147
148	return packet_len;
149	}
150
151	static ssize_t bat_socket_write(struct file file, const char __user buff,
152	size_t len, loff_t *off)
153	{
154	struct socket_client *socket_client = file->private_data;
155	struct bat_priv *bat_priv = socket_client->bat_priv;
156	struct sk_buff *skb;
157	struct icmp_packet_rr *icmp_packet;
158
44524fcd ML	159	struct orig_node *orig_node = NULL;
44524fcd ML	160	struct neigh_node *neigh_node = NULL;
c6c8fea2	161	size_t packet_len = sizeof(struct icmp_packet);
c6c8fea2 SE	162
	163	if (len < sizeof(struct icmp_packet)) {
	164	bat_dbg(DBG_BATMAN, bat_priv,
	165	"Error - can't send packet from char device: "
	166	"invalid packet size\n");
	167	return -EINVAL;
	168	}
	169
	170	if (!bat_priv->primary_if)
	171	return -EFAULT;
	172
	173	if (len >= sizeof(struct icmp_packet_rr))
	174	packet_len = sizeof(struct icmp_packet_rr);
	175
	176	skb = dev_alloc_skb(packet_len + sizeof(struct ethhdr));
	177	if (!skb)
	178	return -ENOMEM;
	179
	180	skb_reserve(skb, sizeof(struct ethhdr));
	181	icmp_packet = (struct icmp_packet_rr *)skb_put(skb, packet_len);
	182
	183	if (!access_ok(VERIFY_READ, buff, packet_len)) {
	184	len = -EFAULT;
	185	goto free_skb;
	186	}
	187
	188	if (__copy_from_user(icmp_packet, buff, packet_len)) {
	189	len = -EFAULT;
	190	goto free_skb;
	191	}
	192
	193	if (icmp_packet->packet_type != BAT_ICMP) {
	194	bat_dbg(DBG_BATMAN, bat_priv,
	195	"Error - can't send packet from char device: "
	196	"got bogus packet type (expected: BAT_ICMP)\n");
	197	len = -EINVAL;
	198	goto free_skb;
	199	}
	200
	201	if (icmp_packet->msg_type != ECHO_REQUEST) {
	202	bat_dbg(DBG_BATMAN, bat_priv,
	203	"Error - can't send packet from char device: "
	204	"got bogus message type (expected: ECHO_REQUEST)\n");
	205	len = -EINVAL;
	206	goto free_skb;
	207	}
	208
	209	icmp_packet->uid = socket_client->index;
	210
	211	if (icmp_packet->version != COMPAT_VERSION) {
	212	icmp_packet->msg_type = PARAMETER_PROBLEM;
	213	icmp_packet->ttl = COMPAT_VERSION;
	214	bat_socket_add_packet(socket_client, icmp_packet, packet_len);
	215	goto free_skb;
	216	}
	217
	218	if (atomic_read(&bat_priv->mesh_state) != MESH_ACTIVE)
	219	goto dst_unreach;
	220
fb778ea1	221	rcu_read_lock();
7aadf889	222	orig_node = orig_hash_find(bat_priv, icmp_packet->dst);
c6c8fea2 SE	223
	224	if (!orig_node)
	225	goto unlock;
	226
44524fcd ML	227	neigh_node = orig_node->router;
	228
	229	if (!neigh_node)
	230	goto unlock;
	231
	232	if (!atomic_inc_not_zero(&neigh_node->refcount)) {
	233	neigh_node = NULL;
c6c8fea2	234	goto unlock;
44524fcd ML	235	}
	236
	237	rcu_read_unlock();
c6c8fea2	238
d0072609	239	if (!neigh_node->if_incoming)
c6c8fea2 SE	240	goto dst_unreach;
c6c8fea2 SE	241
d0072609	242	if (neigh_node->if_incoming->if_status != IF_ACTIVE)
c6c8fea2 SE	243	goto dst_unreach;
	244
	245	memcpy(icmp_packet->orig,
	246	bat_priv->primary_if->net_dev->dev_addr, ETH_ALEN);
	247
	248	if (packet_len == sizeof(struct icmp_packet_rr))
44524fcd	249	memcpy(icmp_packet->rr,
d0072609	250	neigh_node->if_incoming->net_dev->dev_addr, ETH_ALEN);
c6c8fea2	251
d0072609	252	send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
c6c8fea2 SE	253	goto out;
	254
	255	unlock:
44524fcd	256	rcu_read_unlock();
c6c8fea2 SE	257	dst_unreach:
	258	icmp_packet->msg_type = DESTINATION_UNREACHABLE;
	259	bat_socket_add_packet(socket_client, icmp_packet, packet_len);
	260	free_skb:
	261	kfree_skb(skb);
	262	out:
44524fcd ML	263	if (neigh_node)
	264	neigh_node_free_ref(neigh_node);
	265	if (orig_node)
7b36e8ee	266	orig_node_free_ref(orig_node);
c6c8fea2 SE	267	return len;
	268	}
	269
	270	static unsigned int bat_socket_poll(struct file file, poll_table wait)
	271	{
	272	struct socket_client *socket_client = file->private_data;
	273
	274	poll_wait(file, &socket_client->queue_wait, wait);
	275
	276	if (socket_client->queue_len > 0)
	277	return POLLIN \| POLLRDNORM;
	278
	279	return 0;
	280	}
	281
	282	static const struct file_operations fops = {
	283	.owner = THIS_MODULE,
	284	.open = bat_socket_open,
	285	.release = bat_socket_release,
	286	.read = bat_socket_read,
	287	.write = bat_socket_write,
	288	.poll = bat_socket_poll,
	289	.llseek = no_llseek,
	290	};
	291
	292	int bat_socket_setup(struct bat_priv *bat_priv)
	293	{
	294	struct dentry *d;
	295
	296	if (!bat_priv->debug_dir)
	297	goto err;
	298
	299	d = debugfs_create_file(ICMP_SOCKET, S_IFREG \| S_IWUSR \| S_IRUSR,
	300	bat_priv->debug_dir, bat_priv, &fops);
	301	if (d)
	302	goto err;
	303
	304	return 0;
	305
	306	err:
	307	return 1;
	308	}
	309
	310	static void bat_socket_add_packet(struct socket_client *socket_client,
	311	struct icmp_packet_rr *icmp_packet,
	312	size_t icmp_len)
	313	{
	314	struct socket_packet *socket_packet;
	315
	316	socket_packet = kmalloc(sizeof(struct socket_packet), GFP_ATOMIC);
	317
	318	if (!socket_packet)
	319	return;
	320
	321	INIT_LIST_HEAD(&socket_packet->list);
	322	memcpy(&socket_packet->icmp_packet, icmp_packet, icmp_len);
	323	socket_packet->icmp_len = icmp_len;
	324
	325	spin_lock_bh(&socket_client->lock);
	326
	327	/* while waiting for the lock the socket_client could have been
	328	* deleted */
	329	if (!socket_client_hash[icmp_packet->uid]) {
	330	spin_unlock_bh(&socket_client->lock);
331	kfree(socket_packet);
332	return;
333	}
334
335	list_add_tail(&socket_packet->list, &socket_client->queue_list);
336	socket_client->queue_len++;
337
338	if (socket_client->queue_len > 100) {
339	socket_packet = list_first_entry(&socket_client->queue_list,
340	struct socket_packet, list);
341
342	list_del(&socket_packet->list);
343	kfree(socket_packet);
344	socket_client->queue_len--;
345	}
346
347	spin_unlock_bh(&socket_client->lock);
348
349	wake_up(&socket_client->queue_wait);
350	}
351
352	void bat_socket_receive_packet(struct icmp_packet_rr *icmp_packet,
353	size_t icmp_len)
354	{
355	struct socket_client *hash = socket_client_hash[icmp_packet->uid];
356
357	if (hash)
358	bat_socket_add_packet(hash, icmp_packet, icmp_len);
359	}