net: Add 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.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 356 insertions, 0 deletions

diff --git a/net/batman-adv/icmp_socket.c b/net/batman-adv/icmp_socket.c
new file mode 100644
index 000000000000..ecf6d7ffab2e
--- /dev/null
+++ b/net/batman-adv/icmp_socket.c
@@ -0,0 +1,356 @@
+/*
+ * Copyright (C) 2007-2010 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 "types.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;
+	struct batman_if *batman_if;
+	size_t packet_len = sizeof(struct icmp_packet);
+	uint8_t dstaddr[ETH_ALEN];
+
+	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;
+
+	spin_lock_bh(&bat_priv->orig_hash_lock);
+	orig_node = ((struct orig_node *)hash_find(bat_priv->orig_hash,
+						   compare_orig, choose_orig,
+						   icmp_packet->dst));
+
+	if (!orig_node)
+		goto unlock;
+
+	if (!orig_node->router)
+		goto unlock;
+
+	batman_if = orig_node->router->if_incoming;
+	memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
+
+	spin_unlock_bh(&bat_priv->orig_hash_lock);
+
+	if (!batman_if)
+		goto dst_unreach;
+
+	if (batman_if->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, batman_if->net_dev->dev_addr, ETH_ALEN);
+
+
+	send_skb_packet(skb, batman_if, dstaddr);
+
+	goto out;
+
+unlock:
+	spin_unlock_bh(&bat_priv->orig_hash_lock);
+dst_unreach:
+	icmp_packet->msg_type = DESTINATION_UNREACHABLE;
+	bat_socket_add_packet(socket_client, icmp_packet, packet_len);
+free_skb:
+	kfree_skb(skb);
+out:
+	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);
+}