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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /net/batman-adv/icmp_socket.c
Initial import
Diffstat (limited to 'net/batman-adv/icmp_socket.c')
-rw-r--r--net/batman-adv/icmp_socket.c385
1 files changed, 385 insertions, 0 deletions
diff --git a/net/batman-adv/icmp_socket.c b/net/batman-adv/icmp_socket.c
new file mode 100644
index 000000000..161ef8f17
--- /dev/null
+++ b/net/batman-adv/icmp_socket.c
@@ -0,0 +1,385 @@
+/* Copyright (C) 2007-2014 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 "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 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 *socket_client = file->private_data;
+ struct batadv_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 batadv_socket_packet, list);
+
+ list_del(list_pos);
+ kfree(socket_packet);
+ }
+
+ batadv_socket_client_hash[socket_client->index] = NULL;
+ spin_unlock_bh(&socket_client->lock);
+
+ kfree(socket_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);
+ uint8_t *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_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
+ 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_free_ref(primary_if);
+ if (neigh_node)
+ batadv_neigh_node_free_ref(neigh_node);
+ if (orig_node)
+ batadv_orig_node_free_ref(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_receive_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);
+}