diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
commit | 57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch) | |
tree | 5e910f0e82173f4ef4f51111366a3f1299037a7b /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.c | 385 |
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); +} |