2 * L2TP subsystem debugfs
4 * Copyright (c) 2010 Katalix Systems Ltd
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14 #include <linux/module.h>
15 #include <linux/skbuff.h>
16 #include <linux/socket.h>
17 #include <linux/hash.h>
18 #include <linux/l2tp.h>
20 #include <linux/etherdevice.h>
21 #include <linux/spinlock.h>
22 #include <linux/debugfs.h>
27 #include <net/inet_common.h>
28 #include <net/inet_hashtables.h>
29 #include <net/tcp_states.h>
30 #include <net/protocol.h>
32 #include <net/net_namespace.h>
33 #include <net/netns/generic.h>
35 #include "l2tp_core.h"
37 static struct dentry *rootdir;
38 static struct dentry *tunnels;
40 struct l2tp_dfs_seq_data {
42 int tunnel_idx; /* current tunnel */
43 int session_idx; /* index of session within current tunnel */
44 struct l2tp_tunnel *tunnel;
45 struct l2tp_session *session; /* NULL means get next tunnel */
48 static void l2tp_dfs_next_tunnel(struct l2tp_dfs_seq_data *pd)
50 /* Drop reference taken during previous invocation */
52 l2tp_tunnel_dec_refcount(pd->tunnel);
54 pd->tunnel = l2tp_tunnel_get_nth(pd->net, pd->tunnel_idx);
58 static void l2tp_dfs_next_session(struct l2tp_dfs_seq_data *pd)
60 pd->session = l2tp_session_get_nth(pd->tunnel, pd->session_idx);
63 if (pd->session == NULL) {
65 l2tp_dfs_next_tunnel(pd);
70 static void *l2tp_dfs_seq_start(struct seq_file *m, loff_t *offs)
72 struct l2tp_dfs_seq_data *pd = SEQ_START_TOKEN;
78 BUG_ON(m->private == NULL);
81 if (pd->tunnel == NULL)
82 l2tp_dfs_next_tunnel(pd);
84 l2tp_dfs_next_session(pd);
86 /* NULL tunnel and session indicates end of list */
87 if ((pd->tunnel == NULL) && (pd->session == NULL))
95 static void *l2tp_dfs_seq_next(struct seq_file *m, void *v, loff_t *pos)
101 static void l2tp_dfs_seq_stop(struct seq_file *p, void *v)
103 struct l2tp_dfs_seq_data *pd = v;
105 if (!pd || pd == SEQ_START_TOKEN)
108 /* Drop reference taken by last invocation of l2tp_dfs_next_tunnel() */
110 l2tp_tunnel_dec_refcount(pd->tunnel);
113 static void l2tp_dfs_seq_tunnel_show(struct seq_file *m, void *v)
115 struct l2tp_tunnel *tunnel = v;
116 int session_count = 0;
118 struct hlist_node *walk;
119 struct hlist_node *tmp;
121 read_lock_bh(&tunnel->hlist_lock);
122 for (hash = 0; hash < L2TP_HASH_SIZE; hash++) {
123 hlist_for_each_safe(walk, tmp, &tunnel->session_hlist[hash]) {
124 struct l2tp_session *session;
126 session = hlist_entry(walk, struct l2tp_session, hlist);
127 if (session->session_id == 0)
133 read_unlock_bh(&tunnel->hlist_lock);
135 seq_printf(m, "\nTUNNEL %u peer %u", tunnel->tunnel_id, tunnel->peer_tunnel_id);
137 struct inet_sock *inet = inet_sk(tunnel->sock);
139 #if IS_ENABLED(CONFIG_IPV6)
140 if (tunnel->sock->sk_family == AF_INET6) {
141 const struct ipv6_pinfo *np = inet6_sk(tunnel->sock);
143 seq_printf(m, " from %pI6c to %pI6c\n",
144 &np->saddr, &tunnel->sock->sk_v6_daddr);
147 seq_printf(m, " from %pI4 to %pI4\n",
148 &inet->inet_saddr, &inet->inet_daddr);
149 if (tunnel->encap == L2TP_ENCAPTYPE_UDP)
150 seq_printf(m, " source port %hu, dest port %hu\n",
151 ntohs(inet->inet_sport), ntohs(inet->inet_dport));
153 seq_printf(m, " L2TPv%d, %s\n", tunnel->version,
154 tunnel->encap == L2TP_ENCAPTYPE_UDP ? "UDP" :
155 tunnel->encap == L2TP_ENCAPTYPE_IP ? "IP" :
157 seq_printf(m, " %d sessions, refcnt %d/%d\n", session_count,
158 tunnel->sock ? refcount_read(&tunnel->sock->sk_refcnt) : 0,
159 refcount_read(&tunnel->ref_count));
160 seq_printf(m, " %08x rx %ld/%ld/%ld rx %ld/%ld/%ld\n",
162 atomic_long_read(&tunnel->stats.tx_packets),
163 atomic_long_read(&tunnel->stats.tx_bytes),
164 atomic_long_read(&tunnel->stats.tx_errors),
165 atomic_long_read(&tunnel->stats.rx_packets),
166 atomic_long_read(&tunnel->stats.rx_bytes),
167 atomic_long_read(&tunnel->stats.rx_errors));
169 if (tunnel->show != NULL)
170 tunnel->show(m, tunnel);
173 static void l2tp_dfs_seq_session_show(struct seq_file *m, void *v)
175 struct l2tp_session *session = v;
177 seq_printf(m, " SESSION %u, peer %u, %s\n", session->session_id,
178 session->peer_session_id,
179 session->pwtype == L2TP_PWTYPE_ETH ? "ETH" :
180 session->pwtype == L2TP_PWTYPE_PPP ? "PPP" :
182 if (session->send_seq || session->recv_seq)
183 seq_printf(m, " nr %hu, ns %hu\n", session->nr, session->ns);
184 seq_printf(m, " refcnt %d\n", refcount_read(&session->ref_count));
185 seq_printf(m, " config %d/%d/%c/%c/%s/%s %08x %u\n",
186 session->mtu, session->mru,
187 session->recv_seq ? 'R' : '-',
188 session->send_seq ? 'S' : '-',
189 session->data_seq == 1 ? "IPSEQ" :
190 session->data_seq == 2 ? "DATASEQ" : "-",
191 session->lns_mode ? "LNS" : "LAC",
193 jiffies_to_msecs(session->reorder_timeout));
194 seq_printf(m, " offset 0 l2specific %hu/%hu\n",
195 session->l2specific_type, l2tp_get_l2specific_len(session));
196 if (session->cookie_len) {
197 seq_printf(m, " cookie %02x%02x%02x%02x",
198 session->cookie[0], session->cookie[1],
199 session->cookie[2], session->cookie[3]);
200 if (session->cookie_len == 8)
201 seq_printf(m, "%02x%02x%02x%02x",
202 session->cookie[4], session->cookie[5],
203 session->cookie[6], session->cookie[7]);
206 if (session->peer_cookie_len) {
207 seq_printf(m, " peer cookie %02x%02x%02x%02x",
208 session->peer_cookie[0], session->peer_cookie[1],
209 session->peer_cookie[2], session->peer_cookie[3]);
210 if (session->peer_cookie_len == 8)
211 seq_printf(m, "%02x%02x%02x%02x",
212 session->peer_cookie[4], session->peer_cookie[5],
213 session->peer_cookie[6], session->peer_cookie[7]);
217 seq_printf(m, " %hu/%hu tx %ld/%ld/%ld rx %ld/%ld/%ld\n",
218 session->nr, session->ns,
219 atomic_long_read(&session->stats.tx_packets),
220 atomic_long_read(&session->stats.tx_bytes),
221 atomic_long_read(&session->stats.tx_errors),
222 atomic_long_read(&session->stats.rx_packets),
223 atomic_long_read(&session->stats.rx_bytes),
224 atomic_long_read(&session->stats.rx_errors));
226 if (session->show != NULL)
227 session->show(m, session);
230 static int l2tp_dfs_seq_show(struct seq_file *m, void *v)
232 struct l2tp_dfs_seq_data *pd = v;
234 /* display header on line 1 */
235 if (v == SEQ_START_TOKEN) {
236 seq_puts(m, "TUNNEL ID, peer ID from IP to IP\n");
237 seq_puts(m, " L2TPv2/L2TPv3, UDP/IP\n");
238 seq_puts(m, " sessions session-count, refcnt refcnt/sk->refcnt\n");
239 seq_puts(m, " debug tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
240 seq_puts(m, " SESSION ID, peer ID, PWTYPE\n");
241 seq_puts(m, " refcnt cnt\n");
242 seq_puts(m, " offset OFFSET l2specific TYPE/LEN\n");
243 seq_puts(m, " [ cookie ]\n");
244 seq_puts(m, " [ peer cookie ]\n");
245 seq_puts(m, " config mtu/mru/rcvseq/sendseq/dataseq/lns debug reorderto\n");
246 seq_puts(m, " nr/ns tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
250 /* Show the tunnel or session context */
252 l2tp_dfs_seq_tunnel_show(m, pd->tunnel);
254 l2tp_dfs_seq_session_show(m, pd->session);
255 l2tp_session_dec_refcount(pd->session);
262 static const struct seq_operations l2tp_dfs_seq_ops = {
263 .start = l2tp_dfs_seq_start,
264 .next = l2tp_dfs_seq_next,
265 .stop = l2tp_dfs_seq_stop,
266 .show = l2tp_dfs_seq_show,
269 static int l2tp_dfs_seq_open(struct inode *inode, struct file *file)
271 struct l2tp_dfs_seq_data *pd;
272 struct seq_file *seq;
275 pd = kzalloc(sizeof(*pd), GFP_KERNEL);
279 /* Derive the network namespace from the pid opening the
282 pd->net = get_net_ns_by_pid(current->pid);
283 if (IS_ERR(pd->net)) {
284 rc = PTR_ERR(pd->net);
288 rc = seq_open(file, &l2tp_dfs_seq_ops);
292 seq = file->private_data;
305 static int l2tp_dfs_seq_release(struct inode *inode, struct file *file)
307 struct l2tp_dfs_seq_data *pd;
308 struct seq_file *seq;
310 seq = file->private_data;
315 seq_release(inode, file);
320 static const struct file_operations l2tp_dfs_fops = {
321 .owner = THIS_MODULE,
322 .open = l2tp_dfs_seq_open,
325 .release = l2tp_dfs_seq_release,
328 static int __init l2tp_debugfs_init(void)
332 rootdir = debugfs_create_dir("l2tp", NULL);
333 if (IS_ERR(rootdir)) {
334 rc = PTR_ERR(rootdir);
339 tunnels = debugfs_create_file("tunnels", 0600, rootdir, NULL, &l2tp_dfs_fops);
343 pr_info("L2TP debugfs support\n");
347 pr_warn("unable to init\n");
352 static void __exit l2tp_debugfs_exit(void)
354 debugfs_remove(tunnels);
355 debugfs_remove(rootdir);
358 module_init(l2tp_debugfs_init);
359 module_exit(l2tp_debugfs_exit);
361 MODULE_LICENSE("GPL");
362 MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
363 MODULE_DESCRIPTION("L2TP debugfs driver");
364 MODULE_VERSION("1.0");