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8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9
10#include <linux/module.h>
11#include <linux/skbuff.h>
12#include <linux/socket.h>
13#include <linux/hash.h>
14#include <linux/l2tp.h>
15#include <linux/in.h>
16#include <linux/etherdevice.h>
17#include <linux/spinlock.h>
18#include <linux/debugfs.h>
19#include <net/sock.h>
20#include <net/ip.h>
21#include <net/icmp.h>
22#include <net/udp.h>
23#include <net/inet_common.h>
24#include <net/inet_hashtables.h>
25#include <net/tcp_states.h>
26#include <net/protocol.h>
27#include <net/xfrm.h>
28#include <net/net_namespace.h>
29#include <net/netns/generic.h>
30
31#include "l2tp_core.h"
32
33static struct dentry *rootdir;
34static struct dentry *tunnels;
35
36struct l2tp_dfs_seq_data {
37 struct net *net;
38 int tunnel_idx;
39 int session_idx;
40 struct l2tp_tunnel *tunnel;
41 struct l2tp_session *session;
42};
43
44static void l2tp_dfs_next_tunnel(struct l2tp_dfs_seq_data *pd)
45{
46
47 if (pd->tunnel)
48 l2tp_tunnel_dec_refcount(pd->tunnel);
49
50 pd->tunnel = l2tp_tunnel_get_nth(pd->net, pd->tunnel_idx);
51 pd->tunnel_idx++;
52}
53
54static void l2tp_dfs_next_session(struct l2tp_dfs_seq_data *pd)
55{
56
57 if (pd->session)
58 l2tp_session_dec_refcount(pd->session);
59
60 pd->session = l2tp_session_get_nth(pd->tunnel, pd->session_idx);
61 pd->session_idx++;
62
63 if (pd->session == NULL) {
64 pd->session_idx = 0;
65 l2tp_dfs_next_tunnel(pd);
66 }
67
68}
69
70static void *l2tp_dfs_seq_start(struct seq_file *m, loff_t *offs)
71{
72 struct l2tp_dfs_seq_data *pd = SEQ_START_TOKEN;
73 loff_t pos = *offs;
74
75 if (!pos)
76 goto out;
77
78 BUG_ON(m->private == NULL);
79 pd = m->private;
80
81 if (pd->tunnel == NULL)
82 l2tp_dfs_next_tunnel(pd);
83 else
84 l2tp_dfs_next_session(pd);
85
86
87 if ((pd->tunnel == NULL) && (pd->session == NULL))
88 pd = NULL;
89
90out:
91 return pd;
92}
93
94
95static void *l2tp_dfs_seq_next(struct seq_file *m, void *v, loff_t *pos)
96{
97 (*pos)++;
98 return NULL;
99}
100
101static void l2tp_dfs_seq_stop(struct seq_file *p, void *v)
102{
103 struct l2tp_dfs_seq_data *pd = v;
104
105 if (!pd || pd == SEQ_START_TOKEN)
106 return;
107
108
109
110
111 if (pd->session) {
112 l2tp_session_dec_refcount(pd->session);
113 pd->session = NULL;
114 }
115 if (pd->tunnel) {
116 l2tp_tunnel_dec_refcount(pd->tunnel);
117 pd->tunnel = NULL;
118 }
119}
120
121static void l2tp_dfs_seq_tunnel_show(struct seq_file *m, void *v)
122{
123 struct l2tp_tunnel *tunnel = v;
124 int session_count = 0;
125 int hash;
126 struct hlist_node *walk;
127 struct hlist_node *tmp;
128
129 read_lock_bh(&tunnel->hlist_lock);
130 for (hash = 0; hash < L2TP_HASH_SIZE; hash++) {
131 hlist_for_each_safe(walk, tmp, &tunnel->session_hlist[hash]) {
132 struct l2tp_session *session;
133
134 session = hlist_entry(walk, struct l2tp_session, hlist);
135 if (session->session_id == 0)
136 continue;
137
138 session_count++;
139 }
140 }
141 read_unlock_bh(&tunnel->hlist_lock);
142
143 seq_printf(m, "\nTUNNEL %u peer %u", tunnel->tunnel_id, tunnel->peer_tunnel_id);
144 if (tunnel->sock) {
145 struct inet_sock *inet = inet_sk(tunnel->sock);
146
147#if IS_ENABLED(CONFIG_IPV6)
148 if (tunnel->sock->sk_family == AF_INET6) {
149 const struct ipv6_pinfo *np = inet6_sk(tunnel->sock);
150
151 seq_printf(m, " from %pI6c to %pI6c\n",
152 &np->saddr, &tunnel->sock->sk_v6_daddr);
153 } else
154#endif
155 seq_printf(m, " from %pI4 to %pI4\n",
156 &inet->inet_saddr, &inet->inet_daddr);
157 if (tunnel->encap == L2TP_ENCAPTYPE_UDP)
158 seq_printf(m, " source port %hu, dest port %hu\n",
159 ntohs(inet->inet_sport), ntohs(inet->inet_dport));
160 }
161 seq_printf(m, " L2TPv%d, %s\n", tunnel->version,
162 tunnel->encap == L2TP_ENCAPTYPE_UDP ? "UDP" :
163 tunnel->encap == L2TP_ENCAPTYPE_IP ? "IP" :
164 "");
165 seq_printf(m, " %d sessions, refcnt %d/%d\n", session_count,
166 tunnel->sock ? refcount_read(&tunnel->sock->sk_refcnt) : 0,
167 refcount_read(&tunnel->ref_count));
168 seq_printf(m, " %08x rx %ld/%ld/%ld rx %ld/%ld/%ld\n",
169 tunnel->debug,
170 atomic_long_read(&tunnel->stats.tx_packets),
171 atomic_long_read(&tunnel->stats.tx_bytes),
172 atomic_long_read(&tunnel->stats.tx_errors),
173 atomic_long_read(&tunnel->stats.rx_packets),
174 atomic_long_read(&tunnel->stats.rx_bytes),
175 atomic_long_read(&tunnel->stats.rx_errors));
176}
177
178static void l2tp_dfs_seq_session_show(struct seq_file *m, void *v)
179{
180 struct l2tp_session *session = v;
181
182 seq_printf(m, " SESSION %u, peer %u, %s\n", session->session_id,
183 session->peer_session_id,
184 session->pwtype == L2TP_PWTYPE_ETH ? "ETH" :
185 session->pwtype == L2TP_PWTYPE_PPP ? "PPP" :
186 "");
187 if (session->send_seq || session->recv_seq)
188 seq_printf(m, " nr %hu, ns %hu\n", session->nr, session->ns);
189 seq_printf(m, " refcnt %d\n", refcount_read(&session->ref_count));
190 seq_printf(m, " config 0/0/%c/%c/-/%s %08x %u\n",
191 session->recv_seq ? 'R' : '-',
192 session->send_seq ? 'S' : '-',
193 session->lns_mode ? "LNS" : "LAC",
194 session->debug,
195 jiffies_to_msecs(session->reorder_timeout));
196 seq_printf(m, " offset 0 l2specific %hu/%hu\n",
197 session->l2specific_type, l2tp_get_l2specific_len(session));
198 if (session->cookie_len) {
199 seq_printf(m, " cookie %02x%02x%02x%02x",
200 session->cookie[0], session->cookie[1],
201 session->cookie[2], session->cookie[3]);
202 if (session->cookie_len == 8)
203 seq_printf(m, "%02x%02x%02x%02x",
204 session->cookie[4], session->cookie[5],
205 session->cookie[6], session->cookie[7]);
206 seq_printf(m, "\n");
207 }
208 if (session->peer_cookie_len) {
209 seq_printf(m, " peer cookie %02x%02x%02x%02x",
210 session->peer_cookie[0], session->peer_cookie[1],
211 session->peer_cookie[2], session->peer_cookie[3]);
212 if (session->peer_cookie_len == 8)
213 seq_printf(m, "%02x%02x%02x%02x",
214 session->peer_cookie[4], session->peer_cookie[5],
215 session->peer_cookie[6], session->peer_cookie[7]);
216 seq_printf(m, "\n");
217 }
218
219 seq_printf(m, " %hu/%hu tx %ld/%ld/%ld rx %ld/%ld/%ld\n",
220 session->nr, session->ns,
221 atomic_long_read(&session->stats.tx_packets),
222 atomic_long_read(&session->stats.tx_bytes),
223 atomic_long_read(&session->stats.tx_errors),
224 atomic_long_read(&session->stats.rx_packets),
225 atomic_long_read(&session->stats.rx_bytes),
226 atomic_long_read(&session->stats.rx_errors));
227
228 if (session->show != NULL)
229 session->show(m, session);
230}
231
232static int l2tp_dfs_seq_show(struct seq_file *m, void *v)
233{
234 struct l2tp_dfs_seq_data *pd = v;
235
236
237 if (v == SEQ_START_TOKEN) {
238 seq_puts(m, "TUNNEL ID, peer ID from IP to IP\n");
239 seq_puts(m, " L2TPv2/L2TPv3, UDP/IP\n");
240 seq_puts(m, " sessions session-count, refcnt refcnt/sk->refcnt\n");
241 seq_puts(m, " debug tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
242 seq_puts(m, " SESSION ID, peer ID, PWTYPE\n");
243 seq_puts(m, " refcnt cnt\n");
244 seq_puts(m, " offset OFFSET l2specific TYPE/LEN\n");
245 seq_puts(m, " [ cookie ]\n");
246 seq_puts(m, " [ peer cookie ]\n");
247 seq_puts(m, " config mtu/mru/rcvseq/sendseq/dataseq/lns debug reorderto\n");
248 seq_puts(m, " nr/ns tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
249 goto out;
250 }
251
252 if (!pd->session)
253 l2tp_dfs_seq_tunnel_show(m, pd->tunnel);
254 else
255 l2tp_dfs_seq_session_show(m, pd->session);
256
257out:
258 return 0;
259}
260
261static const struct seq_operations l2tp_dfs_seq_ops = {
262 .start = l2tp_dfs_seq_start,
263 .next = l2tp_dfs_seq_next,
264 .stop = l2tp_dfs_seq_stop,
265 .show = l2tp_dfs_seq_show,
266};
267
268static int l2tp_dfs_seq_open(struct inode *inode, struct file *file)
269{
270 struct l2tp_dfs_seq_data *pd;
271 struct seq_file *seq;
272 int rc = -ENOMEM;
273
274 pd = kzalloc(sizeof(*pd), GFP_KERNEL);
275 if (pd == NULL)
276 goto out;
277
278
279
280
281 pd->net = get_net_ns_by_pid(current->pid);
282 if (IS_ERR(pd->net)) {
283 rc = PTR_ERR(pd->net);
284 goto err_free_pd;
285 }
286
287 rc = seq_open(file, &l2tp_dfs_seq_ops);
288 if (rc)
289 goto err_free_net;
290
291 seq = file->private_data;
292 seq->private = pd;
293
294out:
295 return rc;
296
297err_free_net:
298 put_net(pd->net);
299err_free_pd:
300 kfree(pd);
301 goto out;
302}
303
304static int l2tp_dfs_seq_release(struct inode *inode, struct file *file)
305{
306 struct l2tp_dfs_seq_data *pd;
307 struct seq_file *seq;
308
309 seq = file->private_data;
310 pd = seq->private;
311 if (pd->net)
312 put_net(pd->net);
313 kfree(pd);
314 seq_release(inode, file);
315
316 return 0;
317}
318
319static const struct file_operations l2tp_dfs_fops = {
320 .owner = THIS_MODULE,
321 .open = l2tp_dfs_seq_open,
322 .read = seq_read,
323 .llseek = seq_lseek,
324 .release = l2tp_dfs_seq_release,
325};
326
327static int __init l2tp_debugfs_init(void)
328{
329 int rc = 0;
330
331 rootdir = debugfs_create_dir("l2tp", NULL);
332 if (IS_ERR(rootdir)) {
333 rc = PTR_ERR(rootdir);
334 rootdir = NULL;
335 goto out;
336 }
337
338 tunnels = debugfs_create_file("tunnels", 0600, rootdir, NULL, &l2tp_dfs_fops);
339 if (tunnels == NULL)
340 rc = -EIO;
341
342 pr_info("L2TP debugfs support\n");
343
344out:
345 if (rc)
346 pr_warn("unable to init\n");
347
348 return rc;
349}
350
351static void __exit l2tp_debugfs_exit(void)
352{
353 debugfs_remove(tunnels);
354 debugfs_remove(rootdir);
355}
356
357module_init(l2tp_debugfs_init);
358module_exit(l2tp_debugfs_exit);
359
360MODULE_LICENSE("GPL");
361MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
362MODULE_DESCRIPTION("L2TP debugfs driver");
363MODULE_VERSION("1.0");
364
