net: proc: change proc_net_remove to remove_proc_entry
[linux-3.10.git] / net / l2tp / l2tp_debugfs.c
1 /*
2  * L2TP subsystem debugfs
3  *
4  * Copyright (c) 2010 Katalix Systems Ltd
5  *
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.
10  */
11
12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13
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>
19 #include <linux/in.h>
20 #include <linux/etherdevice.h>
21 #include <linux/spinlock.h>
22 #include <linux/debugfs.h>
23 #include <net/sock.h>
24 #include <net/ip.h>
25 #include <net/icmp.h>
26 #include <net/udp.h>
27 #include <net/inet_common.h>
28 #include <net/inet_hashtables.h>
29 #include <net/tcp_states.h>
30 #include <net/protocol.h>
31 #include <net/xfrm.h>
32 #include <net/net_namespace.h>
33 #include <net/netns/generic.h>
34
35 #include "l2tp_core.h"
36
37 static struct dentry *rootdir;
38 static struct dentry *tunnels;
39
40 struct l2tp_dfs_seq_data {
41         struct net *net;
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 */
46 };
47
48 static void l2tp_dfs_next_tunnel(struct l2tp_dfs_seq_data *pd)
49 {
50         pd->tunnel = l2tp_tunnel_find_nth(pd->net, pd->tunnel_idx);
51         pd->tunnel_idx++;
52 }
53
54 static void l2tp_dfs_next_session(struct l2tp_dfs_seq_data *pd)
55 {
56         pd->session = l2tp_session_find_nth(pd->tunnel, pd->session_idx);
57         pd->session_idx++;
58
59         if (pd->session == NULL) {
60                 pd->session_idx = 0;
61                 l2tp_dfs_next_tunnel(pd);
62         }
63
64 }
65
66 static void *l2tp_dfs_seq_start(struct seq_file *m, loff_t *offs)
67 {
68         struct l2tp_dfs_seq_data *pd = SEQ_START_TOKEN;
69         loff_t pos = *offs;
70
71         if (!pos)
72                 goto out;
73
74         BUG_ON(m->private == NULL);
75         pd = m->private;
76
77         if (pd->tunnel == NULL)
78                 l2tp_dfs_next_tunnel(pd);
79         else
80                 l2tp_dfs_next_session(pd);
81
82         /* NULL tunnel and session indicates end of list */
83         if ((pd->tunnel == NULL) && (pd->session == NULL))
84                 pd = NULL;
85
86 out:
87         return pd;
88 }
89
90
91 static void *l2tp_dfs_seq_next(struct seq_file *m, void *v, loff_t *pos)
92 {
93         (*pos)++;
94         return NULL;
95 }
96
97 static void l2tp_dfs_seq_stop(struct seq_file *p, void *v)
98 {
99         /* nothing to do */
100 }
101
102 static void l2tp_dfs_seq_tunnel_show(struct seq_file *m, void *v)
103 {
104         struct l2tp_tunnel *tunnel = v;
105         int session_count = 0;
106         int hash;
107         struct hlist_node *walk;
108         struct hlist_node *tmp;
109
110         read_lock_bh(&tunnel->hlist_lock);
111         for (hash = 0; hash < L2TP_HASH_SIZE; hash++) {
112                 hlist_for_each_safe(walk, tmp, &tunnel->session_hlist[hash]) {
113                         struct l2tp_session *session;
114
115                         session = hlist_entry(walk, struct l2tp_session, hlist);
116                         if (session->session_id == 0)
117                                 continue;
118
119                         session_count++;
120                 }
121         }
122         read_unlock_bh(&tunnel->hlist_lock);
123
124         seq_printf(m, "\nTUNNEL %u peer %u", tunnel->tunnel_id, tunnel->peer_tunnel_id);
125         if (tunnel->sock) {
126                 struct inet_sock *inet = inet_sk(tunnel->sock);
127
128 #if IS_ENABLED(CONFIG_IPV6)
129                 if (tunnel->sock->sk_family == AF_INET6) {
130                         struct ipv6_pinfo *np = inet6_sk(tunnel->sock);
131                         seq_printf(m, " from %pI6c to %pI6c\n",
132                                 &np->saddr, &np->daddr);
133                 } else
134 #endif
135                 seq_printf(m, " from %pI4 to %pI4\n",
136                            &inet->inet_saddr, &inet->inet_daddr);
137                 if (tunnel->encap == L2TP_ENCAPTYPE_UDP)
138                         seq_printf(m, " source port %hu, dest port %hu\n",
139                                    ntohs(inet->inet_sport), ntohs(inet->inet_dport));
140         }
141         seq_printf(m, " L2TPv%d, %s\n", tunnel->version,
142                    tunnel->encap == L2TP_ENCAPTYPE_UDP ? "UDP" :
143                    tunnel->encap == L2TP_ENCAPTYPE_IP ? "IP" :
144                    "");
145         seq_printf(m, " %d sessions, refcnt %d/%d\n", session_count,
146                    tunnel->sock ? atomic_read(&tunnel->sock->sk_refcnt) : 0,
147                    atomic_read(&tunnel->ref_count));
148
149         seq_printf(m, " %08x rx %llu/%llu/%llu rx %llu/%llu/%llu\n",
150                    tunnel->debug,
151                    (unsigned long long)tunnel->stats.tx_packets,
152                    (unsigned long long)tunnel->stats.tx_bytes,
153                    (unsigned long long)tunnel->stats.tx_errors,
154                    (unsigned long long)tunnel->stats.rx_packets,
155                    (unsigned long long)tunnel->stats.rx_bytes,
156                    (unsigned long long)tunnel->stats.rx_errors);
157
158         if (tunnel->show != NULL)
159                 tunnel->show(m, tunnel);
160 }
161
162 static void l2tp_dfs_seq_session_show(struct seq_file *m, void *v)
163 {
164         struct l2tp_session *session = v;
165
166         seq_printf(m, "  SESSION %u, peer %u, %s\n", session->session_id,
167                    session->peer_session_id,
168                    session->pwtype == L2TP_PWTYPE_ETH ? "ETH" :
169                    session->pwtype == L2TP_PWTYPE_PPP ? "PPP" :
170                    "");
171         if (session->send_seq || session->recv_seq)
172                 seq_printf(m, "   nr %hu, ns %hu\n", session->nr, session->ns);
173         seq_printf(m, "   refcnt %d\n", atomic_read(&session->ref_count));
174         seq_printf(m, "   config %d/%d/%c/%c/%s/%s %08x %u\n",
175                    session->mtu, session->mru,
176                    session->recv_seq ? 'R' : '-',
177                    session->send_seq ? 'S' : '-',
178                    session->data_seq == 1 ? "IPSEQ" :
179                    session->data_seq == 2 ? "DATASEQ" : "-",
180                    session->lns_mode ? "LNS" : "LAC",
181                    session->debug,
182                    jiffies_to_msecs(session->reorder_timeout));
183         seq_printf(m, "   offset %hu l2specific %hu/%hu\n",
184                    session->offset, session->l2specific_type, session->l2specific_len);
185         if (session->cookie_len) {
186                 seq_printf(m, "   cookie %02x%02x%02x%02x",
187                            session->cookie[0], session->cookie[1],
188                            session->cookie[2], session->cookie[3]);
189                 if (session->cookie_len == 8)
190                         seq_printf(m, "%02x%02x%02x%02x",
191                                    session->cookie[4], session->cookie[5],
192                                    session->cookie[6], session->cookie[7]);
193                 seq_printf(m, "\n");
194         }
195         if (session->peer_cookie_len) {
196                 seq_printf(m, "   peer cookie %02x%02x%02x%02x",
197                            session->peer_cookie[0], session->peer_cookie[1],
198                            session->peer_cookie[2], session->peer_cookie[3]);
199                 if (session->peer_cookie_len == 8)
200                         seq_printf(m, "%02x%02x%02x%02x",
201                                    session->peer_cookie[4], session->peer_cookie[5],
202                                    session->peer_cookie[6], session->peer_cookie[7]);
203                 seq_printf(m, "\n");
204         }
205
206         seq_printf(m, "   %hu/%hu tx %llu/%llu/%llu rx %llu/%llu/%llu\n",
207                    session->nr, session->ns,
208                    (unsigned long long)session->stats.tx_packets,
209                    (unsigned long long)session->stats.tx_bytes,
210                    (unsigned long long)session->stats.tx_errors,
211                    (unsigned long long)session->stats.rx_packets,
212                    (unsigned long long)session->stats.rx_bytes,
213                    (unsigned long long)session->stats.rx_errors);
214
215         if (session->show != NULL)
216                 session->show(m, session);
217 }
218
219 static int l2tp_dfs_seq_show(struct seq_file *m, void *v)
220 {
221         struct l2tp_dfs_seq_data *pd = v;
222
223         /* display header on line 1 */
224         if (v == SEQ_START_TOKEN) {
225                 seq_puts(m, "TUNNEL ID, peer ID from IP to IP\n");
226                 seq_puts(m, " L2TPv2/L2TPv3, UDP/IP\n");
227                 seq_puts(m, " sessions session-count, refcnt refcnt/sk->refcnt\n");
228                 seq_puts(m, " debug tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
229                 seq_puts(m, "  SESSION ID, peer ID, PWTYPE\n");
230                 seq_puts(m, "   refcnt cnt\n");
231                 seq_puts(m, "   offset OFFSET l2specific TYPE/LEN\n");
232                 seq_puts(m, "   [ cookie ]\n");
233                 seq_puts(m, "   [ peer cookie ]\n");
234                 seq_puts(m, "   config mtu/mru/rcvseq/sendseq/dataseq/lns debug reorderto\n");
235                 seq_puts(m, "   nr/ns tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
236                 goto out;
237         }
238
239         /* Show the tunnel or session context */
240         if (pd->session == NULL)
241                 l2tp_dfs_seq_tunnel_show(m, pd->tunnel);
242         else
243                 l2tp_dfs_seq_session_show(m, pd->session);
244
245 out:
246         return 0;
247 }
248
249 static const struct seq_operations l2tp_dfs_seq_ops = {
250         .start          = l2tp_dfs_seq_start,
251         .next           = l2tp_dfs_seq_next,
252         .stop           = l2tp_dfs_seq_stop,
253         .show           = l2tp_dfs_seq_show,
254 };
255
256 static int l2tp_dfs_seq_open(struct inode *inode, struct file *file)
257 {
258         struct l2tp_dfs_seq_data *pd;
259         struct seq_file *seq;
260         int rc = -ENOMEM;
261
262         pd = kzalloc(sizeof(*pd), GFP_KERNEL);
263         if (pd == NULL)
264                 goto out;
265
266         /* Derive the network namespace from the pid opening the
267          * file.
268          */
269         pd->net = get_net_ns_by_pid(current->pid);
270         if (IS_ERR(pd->net)) {
271                 rc = PTR_ERR(pd->net);
272                 goto err_free_pd;
273         }
274
275         rc = seq_open(file, &l2tp_dfs_seq_ops);
276         if (rc)
277                 goto err_free_net;
278
279         seq = file->private_data;
280         seq->private = pd;
281
282 out:
283         return rc;
284
285 err_free_net:
286         put_net(pd->net);
287 err_free_pd:
288         kfree(pd);
289         goto out;
290 }
291
292 static int l2tp_dfs_seq_release(struct inode *inode, struct file *file)
293 {
294         struct l2tp_dfs_seq_data *pd;
295         struct seq_file *seq;
296
297         seq = file->private_data;
298         pd = seq->private;
299         if (pd->net)
300                 put_net(pd->net);
301         kfree(pd);
302         seq_release(inode, file);
303
304         return 0;
305 }
306
307 static const struct file_operations l2tp_dfs_fops = {
308         .owner          = THIS_MODULE,
309         .open           = l2tp_dfs_seq_open,
310         .read           = seq_read,
311         .llseek         = seq_lseek,
312         .release        = l2tp_dfs_seq_release,
313 };
314
315 static int __init l2tp_debugfs_init(void)
316 {
317         int rc = 0;
318
319         rootdir = debugfs_create_dir("l2tp", NULL);
320         if (IS_ERR(rootdir)) {
321                 rc = PTR_ERR(rootdir);
322                 rootdir = NULL;
323                 goto out;
324         }
325
326         tunnels = debugfs_create_file("tunnels", 0600, rootdir, NULL, &l2tp_dfs_fops);
327         if (tunnels == NULL)
328                 rc = -EIO;
329
330         pr_info("L2TP debugfs support\n");
331
332 out:
333         if (rc)
334                 pr_warn("unable to init\n");
335
336         return rc;
337 }
338
339 static void __exit l2tp_debugfs_exit(void)
340 {
341         debugfs_remove(tunnels);
342         debugfs_remove(rootdir);
343 }
344
345 module_init(l2tp_debugfs_init);
346 module_exit(l2tp_debugfs_exit);
347
348 MODULE_LICENSE("GPL");
349 MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
350 MODULE_DESCRIPTION("L2TP debugfs driver");
351 MODULE_VERSION("1.0");