1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (C) 2007-2019 B.A.T.M.A.N. contributors:
7 #include "icmp_socket.h"
10 #include <linux/atomic.h>
11 #include <linux/compiler.h>
12 #include <linux/debugfs.h>
13 #include <linux/errno.h>
14 #include <linux/etherdevice.h>
15 #include <linux/eventpoll.h>
16 #include <linux/export.h>
17 #include <linux/fcntl.h>
19 #include <linux/gfp.h>
20 #include <linux/if_ether.h>
21 #include <linux/kernel.h>
22 #include <linux/list.h>
23 #include <linux/module.h>
24 #include <linux/netdevice.h>
25 #include <linux/pkt_sched.h>
26 #include <linux/poll.h>
27 #include <linux/printk.h>
28 #include <linux/sched.h> /* for linux/wait.h */
29 #include <linux/skbuff.h>
30 #include <linux/slab.h>
31 #include <linux/spinlock.h>
32 #include <linux/stddef.h>
33 #include <linux/string.h>
34 #include <linux/uaccess.h>
35 #include <linux/wait.h>
36 #include <uapi/linux/batadv_packet.h>
39 #include "hard-interface.h"
41 #include "originator.h"
44 static struct batadv_socket_client *batadv_socket_client_hash[256];
46 static void batadv_socket_add_packet(struct batadv_socket_client *socket_client,
47 struct batadv_icmp_header *icmph,
51 * batadv_socket_init() - Initialize soft interface independent socket data
53 void batadv_socket_init(void)
55 memset(batadv_socket_client_hash, 0, sizeof(batadv_socket_client_hash));
58 static int batadv_socket_open(struct inode *inode, struct file *file)
61 struct batadv_socket_client *socket_client;
63 if (!try_module_get(THIS_MODULE))
66 batadv_debugfs_deprecated(file, "");
68 stream_open(inode, file);
70 socket_client = kmalloc(sizeof(*socket_client), GFP_KERNEL);
72 module_put(THIS_MODULE);
76 for (i = 0; i < ARRAY_SIZE(batadv_socket_client_hash); i++) {
77 if (!batadv_socket_client_hash[i]) {
78 batadv_socket_client_hash[i] = socket_client;
83 if (i == ARRAY_SIZE(batadv_socket_client_hash)) {
84 pr_err("Error - can't add another packet client: maximum number of clients reached\n");
86 module_put(THIS_MODULE);
90 INIT_LIST_HEAD(&socket_client->queue_list);
91 socket_client->queue_len = 0;
92 socket_client->index = i;
93 socket_client->bat_priv = inode->i_private;
94 spin_lock_init(&socket_client->lock);
95 init_waitqueue_head(&socket_client->queue_wait);
97 file->private_data = socket_client;
102 static int batadv_socket_release(struct inode *inode, struct file *file)
104 struct batadv_socket_client *client = file->private_data;
105 struct batadv_socket_packet *packet, *tmp;
107 spin_lock_bh(&client->lock);
109 /* for all packets in the queue ... */
110 list_for_each_entry_safe(packet, tmp, &client->queue_list, list) {
111 list_del(&packet->list);
115 batadv_socket_client_hash[client->index] = NULL;
116 spin_unlock_bh(&client->lock);
119 module_put(THIS_MODULE);
124 static ssize_t batadv_socket_read(struct file *file, char __user *buf,
125 size_t count, loff_t *ppos)
127 struct batadv_socket_client *socket_client = file->private_data;
128 struct batadv_socket_packet *socket_packet;
132 if ((file->f_flags & O_NONBLOCK) && socket_client->queue_len == 0)
135 if (!buf || count < sizeof(struct batadv_icmp_packet))
138 if (!access_ok(buf, count))
141 error = wait_event_interruptible(socket_client->queue_wait,
142 socket_client->queue_len);
147 spin_lock_bh(&socket_client->lock);
149 socket_packet = list_first_entry(&socket_client->queue_list,
150 struct batadv_socket_packet, list);
151 list_del(&socket_packet->list);
152 socket_client->queue_len--;
154 spin_unlock_bh(&socket_client->lock);
156 packet_len = min(count, socket_packet->icmp_len);
157 error = copy_to_user(buf, &socket_packet->icmp_packet, packet_len);
159 kfree(socket_packet);
167 static ssize_t batadv_socket_write(struct file *file, const char __user *buff,
168 size_t len, loff_t *off)
170 struct batadv_socket_client *socket_client = file->private_data;
171 struct batadv_priv *bat_priv = socket_client->bat_priv;
172 struct batadv_hard_iface *primary_if = NULL;
174 struct batadv_icmp_packet_rr *icmp_packet_rr;
175 struct batadv_icmp_header *icmp_header;
176 struct batadv_orig_node *orig_node = NULL;
177 struct batadv_neigh_node *neigh_node = NULL;
178 size_t packet_len = sizeof(struct batadv_icmp_packet);
181 if (len < sizeof(struct batadv_icmp_header)) {
182 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
183 "Error - can't send packet from char device: invalid packet size\n");
187 primary_if = batadv_primary_if_get_selected(bat_priv);
194 if (len >= BATADV_ICMP_MAX_PACKET_SIZE)
195 packet_len = BATADV_ICMP_MAX_PACKET_SIZE;
199 skb = netdev_alloc_skb_ip_align(NULL, packet_len + ETH_HLEN);
205 skb->priority = TC_PRIO_CONTROL;
206 skb_reserve(skb, ETH_HLEN);
207 icmp_header = skb_put(skb, packet_len);
209 if (copy_from_user(icmp_header, buff, packet_len)) {
214 if (icmp_header->packet_type != BATADV_ICMP) {
215 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
216 "Error - can't send packet from char device: got bogus packet type (expected: BAT_ICMP)\n");
221 switch (icmp_header->msg_type) {
222 case BATADV_ECHO_REQUEST:
223 if (len < sizeof(struct batadv_icmp_packet)) {
224 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
225 "Error - can't send packet from char device: invalid packet size\n");
230 if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
233 orig_node = batadv_orig_hash_find(bat_priv, icmp_header->dst);
237 neigh_node = batadv_orig_router_get(orig_node,
242 if (!neigh_node->if_incoming)
245 if (neigh_node->if_incoming->if_status != BATADV_IF_ACTIVE)
248 icmp_packet_rr = (struct batadv_icmp_packet_rr *)icmp_header;
249 if (packet_len == sizeof(*icmp_packet_rr)) {
250 addr = neigh_node->if_incoming->net_dev->dev_addr;
251 ether_addr_copy(icmp_packet_rr->rr[0], addr);
256 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
257 "Error - can't send packet from char device: got unknown message type\n");
262 icmp_header->uid = socket_client->index;
264 if (icmp_header->version != BATADV_COMPAT_VERSION) {
265 icmp_header->msg_type = BATADV_PARAMETER_PROBLEM;
266 icmp_header->version = BATADV_COMPAT_VERSION;
267 batadv_socket_add_packet(socket_client, icmp_header,
272 ether_addr_copy(icmp_header->orig, primary_if->net_dev->dev_addr);
274 batadv_send_unicast_skb(skb, neigh_node);
278 icmp_header->msg_type = BATADV_DESTINATION_UNREACHABLE;
279 batadv_socket_add_packet(socket_client, icmp_header, packet_len);
284 batadv_hardif_put(primary_if);
286 batadv_neigh_node_put(neigh_node);
288 batadv_orig_node_put(orig_node);
292 static __poll_t batadv_socket_poll(struct file *file, poll_table *wait)
294 struct batadv_socket_client *socket_client = file->private_data;
296 poll_wait(file, &socket_client->queue_wait, wait);
298 if (socket_client->queue_len > 0)
299 return EPOLLIN | EPOLLRDNORM;
304 static const struct file_operations batadv_fops = {
305 .owner = THIS_MODULE,
306 .open = batadv_socket_open,
307 .release = batadv_socket_release,
308 .read = batadv_socket_read,
309 .write = batadv_socket_write,
310 .poll = batadv_socket_poll,
315 * batadv_socket_setup() - Create debugfs "socket" file
316 * @bat_priv: the bat priv with all the soft interface information
318 void batadv_socket_setup(struct batadv_priv *bat_priv)
320 debugfs_create_file(BATADV_ICMP_SOCKET, 0600, bat_priv->debug_dir,
321 bat_priv, &batadv_fops);
325 * batadv_socket_add_packet() - schedule an icmp packet to be sent to
326 * userspace on an icmp socket.
327 * @socket_client: the socket this packet belongs to
328 * @icmph: pointer to the header of the icmp packet
329 * @icmp_len: total length of the icmp packet
331 static void batadv_socket_add_packet(struct batadv_socket_client *socket_client,
332 struct batadv_icmp_header *icmph,
335 struct batadv_socket_packet *socket_packet;
338 socket_packet = kmalloc(sizeof(*socket_packet), GFP_ATOMIC);
344 /* check the maximum length before filling the buffer */
345 if (len > sizeof(socket_packet->icmp_packet))
346 len = sizeof(socket_packet->icmp_packet);
348 INIT_LIST_HEAD(&socket_packet->list);
349 memcpy(&socket_packet->icmp_packet, icmph, len);
350 socket_packet->icmp_len = len;
352 spin_lock_bh(&socket_client->lock);
354 /* while waiting for the lock the socket_client could have been
357 if (!batadv_socket_client_hash[icmph->uid]) {
358 spin_unlock_bh(&socket_client->lock);
359 kfree(socket_packet);
363 list_add_tail(&socket_packet->list, &socket_client->queue_list);
364 socket_client->queue_len++;
366 if (socket_client->queue_len > 100) {
367 socket_packet = list_first_entry(&socket_client->queue_list,
368 struct batadv_socket_packet,
371 list_del(&socket_packet->list);
372 kfree(socket_packet);
373 socket_client->queue_len--;
376 spin_unlock_bh(&socket_client->lock);
378 wake_up(&socket_client->queue_wait);
382 * batadv_socket_receive_packet() - schedule an icmp packet to be received
383 * locally and sent to userspace.
384 * @icmph: pointer to the header of the icmp packet
385 * @icmp_len: total length of the icmp packet
387 void batadv_socket_receive_packet(struct batadv_icmp_header *icmph,
390 struct batadv_socket_client *hash;
392 hash = batadv_socket_client_hash[icmph->uid];
394 batadv_socket_add_packet(hash, icmph, icmp_len);