staging: batman-adv meshing protocol

B.A.T.M.A.N. (better approach to mobile ad-hoc networking) is
a routing protocol for multi-hop ad-hoc mesh networks. The
networks may be wired or wireless. See
http://www.open-mesh.org/ for more information and user space
tools.

This is the first submission for inclusion in staging.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 337 insertions, 0 deletions

diff --git a/drivers/staging/batman-adv/device.c b/drivers/staging/batman-adv/device.c
new file mode 100644
index 00000000000..1e7d1f88674
--- /dev/null
+++ b/drivers/staging/batman-adv/device.c
@@ -0,0 +1,337 @@
+/*
+ * Copyright (C) 2007-2009 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 "device.h"
+#include "log.h"
+#include "send.h"
+#include "types.h"
+#include "hash.h"
+
+#include "compat.h"
+
+static struct class *batman_class;
+
+static int Major;	/* Major number assigned to our device driver */
+
+static const struct file_operations fops = {
+	.open = bat_device_open,
+	.release = bat_device_release,
+	.read = bat_device_read,
+	.write = bat_device_write,
+	.poll = bat_device_poll,
+};
+
+static struct device_client *device_client_hash[256];
+
+void bat_device_init(void)
+{
+	int i;
+
+	for (i = 0; i < 256; i++)
+		device_client_hash[i] = NULL;
+}
+
+int bat_device_setup(void)
+{
+	int tmp_major;
+
+	if (Major)
+		return 1;
+
+	/* register our device - kernel assigns a free major number */
+	tmp_major = register_chrdev(0, DRIVER_DEVICE, &fops);
+	if (tmp_major < 0) {
+		debug_log(LOG_TYPE_WARN, "Registering the character device failed with %d\n",
+			  tmp_major);
+		return 0;
+	}
+
+	batman_class = class_create(THIS_MODULE, "batman-adv");
+
+	if (IS_ERR(batman_class)) {
+		debug_log(LOG_TYPE_WARN, "Could not register class 'batman-adv' \n");
+		return 0;
+	}
+
+	device_create(batman_class, NULL, MKDEV(tmp_major, 0), NULL,
+		      "batman-adv");
+
+	Major = tmp_major;
+	return 1;
+}
+
+void bat_device_destroy(void)
+{
+	if (!Major)
+		return;
+
+	device_destroy(batman_class, MKDEV(Major, 0));
+	class_destroy(batman_class);
+
+	/* Unregister the device */
+	unregister_chrdev(Major, DRIVER_DEVICE);
+
+	Major = 0;
+}
+
+int bat_device_open(struct inode *inode, struct file *file)
+{
+	unsigned int i;
+	struct device_client *device_client;
+
+	device_client = kmalloc(sizeof(struct device_client), GFP_KERNEL);
+
+	if (!device_client)
+		return -ENOMEM;
+
+	for (i = 0; i < 256; i++) {
+		if (!device_client_hash[i]) {
+			device_client_hash[i] = device_client;
+			break;
+		}
+	}
+
+	if (device_client_hash[i] != device_client) {
+		debug_log(LOG_TYPE_WARN, "Error - can't add another packet client: maximum number of clients reached \n");
+		kfree(device_client);
+		return -EXFULL;
+	}
+
+	INIT_LIST_HEAD(&device_client->queue_list);
+	device_client->queue_len = 0;
+	device_client->index = i;
+	device_client->lock = __SPIN_LOCK_UNLOCKED(device_client->lock);
+	init_waitqueue_head(&device_client->queue_wait);
+
+	file->private_data = device_client;
+
+	inc_module_count();
+	return 0;
+}
+
+int bat_device_release(struct inode *inode, struct file *file)
+{
+	struct device_client *device_client =
+		(struct device_client *)file->private_data;
+	struct device_packet *device_packet;
+	struct list_head *list_pos, *list_pos_tmp;
+
+	spin_lock(&device_client->lock);
+
+	/* for all packets in the queue ... */
+	list_for_each_safe(list_pos, list_pos_tmp, &device_client->queue_list) {
+		device_packet = list_entry(list_pos,
+					   struct device_packet, list);
+
+		list_del(list_pos);
+		kfree(device_packet);
+	}
+
+	device_client_hash[device_client->index] = NULL;
+	spin_unlock(&device_client->lock);
+
+	kfree(device_client);
+	dec_module_count();
+
+	return 0;
+}
+
+ssize_t bat_device_read(struct file *file, char __user *buf, size_t count,
+			loff_t *ppos)
+{
+	struct device_client *device_client =
+		(struct device_client *)file->private_data;
+	struct device_packet *device_packet;
+	int error;
+
+	if ((file->f_flags & O_NONBLOCK) && (device_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(device_client->queue_wait,
+					 device_client->queue_len);
+
+	if (error)
+		return error;
+
+	spin_lock(&device_client->lock);
+
+	device_packet = list_first_entry(&device_client->queue_list,
+					 struct device_packet, list);
+	list_del(&device_packet->list);
+	device_client->queue_len--;
+
+	spin_unlock(&device_client->lock);
+
+	error = __copy_to_user(buf, &device_packet->icmp_packet,
+			       sizeof(struct icmp_packet));
+
+	kfree(device_packet);
+
+	if (error)
+		return error;
+
+	return sizeof(struct icmp_packet);
+}
+
+ssize_t bat_device_write(struct file *file, const char __user *buff,
+			 size_t len, loff_t *off)
+{
+	struct device_client *device_client =
+		(struct device_client *)file->private_data;
+	struct icmp_packet icmp_packet;
+	struct orig_node *orig_node;
+	struct batman_if *batman_if;
+
+	if (len < sizeof(struct icmp_packet)) {
+		debug_log(LOG_TYPE_NOTICE, "Error - can't send packet from char device: invalid packet size\n");
+		return -EINVAL;
+	}
+
+	if (!access_ok(VERIFY_READ, buff, sizeof(struct icmp_packet)))
+		return -EFAULT;
+
+	if (__copy_from_user(&icmp_packet, buff, sizeof(icmp_packet)))
+		return -EFAULT;
+
+	if (icmp_packet.packet_type != BAT_ICMP) {
+		debug_log(LOG_TYPE_NOTICE, "Error - can't send packet from char device: got bogus packet type (expected: BAT_ICMP)\n");
+		return -EINVAL;
+	}
+
+	if (icmp_packet.msg_type != ECHO_REQUEST) {
+		debug_log(LOG_TYPE_NOTICE, "Error - can't send packet from char device: got bogus message type (expected: ECHO_REQUEST)\n");
+		return -EINVAL;
+	}
+
+	icmp_packet.uid = device_client->index;
+
+	if (icmp_packet.version != COMPAT_VERSION) {
+		icmp_packet.msg_type = PARAMETER_PROBLEM;
+		icmp_packet.ttl = COMPAT_VERSION;
+		bat_device_add_packet(device_client, &icmp_packet);
+		goto out;
+	}
+
+	if (atomic_read(&module_state) != MODULE_ACTIVE)
+		goto dst_unreach;
+
+	spin_lock(&orig_hash_lock);
+	orig_node = ((struct orig_node *)hash_find(orig_hash, icmp_packet.dst));
+
+	if (!orig_node)
+		goto unlock;
+
+	if (!orig_node->router)
+		goto unlock;
+
+	batman_if = orig_node->batman_if;
+
+	if (!batman_if)
+		goto unlock;
+
+	memcpy(icmp_packet.orig,
+	       batman_if->net_dev->dev_addr,
+	       ETH_ALEN);
+
+	send_raw_packet((unsigned char *)&icmp_packet,
+			sizeof(struct icmp_packet),
+			batman_if, orig_node->router->addr);
+
+	spin_unlock(&orig_hash_lock);
+	goto out;
+
+unlock:
+	spin_unlock(&orig_hash_lock);
+dst_unreach:
+	icmp_packet.msg_type = DESTINATION_UNREACHABLE;
+	bat_device_add_packet(device_client, &icmp_packet);
+out:
+	return len;
+}
+
+unsigned int bat_device_poll(struct file *file, poll_table *wait)
+{
+	struct device_client *device_client =
+		(struct device_client *)file->private_data;
+
+	poll_wait(file, &device_client->queue_wait, wait);
+
+	if (device_client->queue_len > 0)
+		return POLLIN | POLLRDNORM;
+
+	return 0;
+}
+
+void bat_device_add_packet(struct device_client *device_client,
+			   struct icmp_packet *icmp_packet)
+{
+	struct device_packet *device_packet;
+
+	device_packet = kmalloc(sizeof(struct device_packet), GFP_KERNEL);
+
+	if (!device_packet)
+		return;
+
+	INIT_LIST_HEAD(&device_packet->list);
+	memcpy(&device_packet->icmp_packet, icmp_packet,
+	       sizeof(struct icmp_packet));
+
+	spin_lock(&device_client->lock);
+
+	/* while waiting for the lock the device_client could have been
+	 * deleted */
+	if (!device_client_hash[icmp_packet->uid]) {
+		spin_unlock(&device_client->lock);
+		kfree(device_packet);
+		return;
+	}
+
+	list_add_tail(&device_packet->list, &device_client->queue_list);
+	device_client->queue_len++;
+
+	if (device_client->queue_len > 100) {
+		device_packet = list_first_entry(&device_client->queue_list,
+						 struct device_packet, list);
+
+		list_del(&device_packet->list);
+		kfree(device_packet);
+		device_client->queue_len--;
+	}
+
+	spin_unlock(&device_client->lock);
+
+	wake_up(&device_client->queue_wait);
+}
+
+void bat_device_receive_packet(struct icmp_packet *icmp_packet)
+{
+	struct device_client *hash = device_client_hash[icmp_packet->uid];
+
+	if (hash)
+		bat_device_add_packet(hash, icmp_packet);
+}