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 #include <linux/module.h> 13 #include <linux/skbuff.h> 14 #include <linux/socket.h> 15 #include <linux/hash.h> 16 #include <linux/l2tp.h> 17 #include <linux/in.h> 18 #include <linux/etherdevice.h> 19 #include <linux/spinlock.h> 20 #include <linux/debugfs.h> 21 #include <net/sock.h> 22 #include <net/ip.h> 23 #include <net/icmp.h> 24 #include <net/udp.h> 25 #include <net/inet_common.h> 26 #include <net/inet_hashtables.h> 27 #include <net/tcp_states.h> 28 #include <net/protocol.h> 29 #include <net/xfrm.h> 30 #include <net/net_namespace.h> 31 #include <net/netns/generic.h> 32 33 #include "l2tp_core.h" 34 35 static struct dentry *rootdir; 36 static struct dentry *tunnels; 37 38 struct l2tp_dfs_seq_data { 39 struct net *net; 40 int tunnel_idx; /* current tunnel */ 41 int session_idx; /* index of session within current tunnel */ 42 struct l2tp_tunnel *tunnel; 43 struct l2tp_session *session; /* NULL means get next tunnel */ 44 }; 45 46 static void l2tp_dfs_next_tunnel(struct l2tp_dfs_seq_data *pd) 47 { 48 pd->tunnel = l2tp_tunnel_find_nth(pd->net, pd->tunnel_idx); 49 pd->tunnel_idx++; 50 } 51 52 static void l2tp_dfs_next_session(struct l2tp_dfs_seq_data *pd) 53 { 54 pd->session = l2tp_session_find_nth(pd->tunnel, pd->session_idx); 55 pd->session_idx++; 56 57 if (pd->session == NULL) { 58 pd->session_idx = 0; 59 l2tp_dfs_next_tunnel(pd); 60 } 61 62 } 63 64 static void *l2tp_dfs_seq_start(struct seq_file *m, loff_t *offs) 65 { 66 struct l2tp_dfs_seq_data *pd = SEQ_START_TOKEN; 67 loff_t pos = *offs; 68 69 if (!pos) 70 goto out; 71 72 BUG_ON(m->private == NULL); 73 pd = m->private; 74 75 if (pd->tunnel == NULL) 76 l2tp_dfs_next_tunnel(pd); 77 else 78 l2tp_dfs_next_session(pd); 79 80 /* NULL tunnel and session indicates end of list */ 81 if ((pd->tunnel == NULL) && (pd->session == NULL)) 82 pd = NULL; 83 84 out: 85 return pd; 86 } 87 88 89 static void *l2tp_dfs_seq_next(struct seq_file *m, void *v, loff_t *pos) 90 { 91 (*pos)++; 92 return NULL; 93 } 94 95 static void l2tp_dfs_seq_stop(struct seq_file *p, void *v) 96 { 97 /* nothing to do */ 98 } 99 100 static void l2tp_dfs_seq_tunnel_show(struct seq_file *m, void *v) 101 { 102 struct l2tp_tunnel *tunnel = v; 103 int session_count = 0; 104 int hash; 105 struct hlist_node *walk; 106 struct hlist_node *tmp; 107 108 read_lock_bh(&tunnel->hlist_lock); 109 for (hash = 0; hash < L2TP_HASH_SIZE; hash++) { 110 hlist_for_each_safe(walk, tmp, &tunnel->session_hlist[hash]) { 111 struct l2tp_session *session; 112 113 session = hlist_entry(walk, struct l2tp_session, hlist); 114 if (session->session_id == 0) 115 continue; 116 117 session_count++; 118 } 119 } 120 read_unlock_bh(&tunnel->hlist_lock); 121 122 seq_printf(m, "\nTUNNEL %u peer %u", tunnel->tunnel_id, tunnel->peer_tunnel_id); 123 if (tunnel->sock) { 124 struct inet_sock *inet = inet_sk(tunnel->sock); 125 seq_printf(m, " from %pI4 to %pI4\n", 126 &inet->inet_saddr, &inet->inet_daddr); 127 if (tunnel->encap == L2TP_ENCAPTYPE_UDP) 128 seq_printf(m, " source port %hu, dest port %hu\n", 129 ntohs(inet->inet_sport), ntohs(inet->inet_dport)); 130 } 131 seq_printf(m, " L2TPv%d, %s\n", tunnel->version, 132 tunnel->encap == L2TP_ENCAPTYPE_UDP ? "UDP" : 133 tunnel->encap == L2TP_ENCAPTYPE_IP ? "IP" : 134 ""); 135 seq_printf(m, " %d sessions, refcnt %d/%d\n", session_count, 136 tunnel->sock ? atomic_read(&tunnel->sock->sk_refcnt) : 0, 137 atomic_read(&tunnel->ref_count)); 138 139 seq_printf(m, " %08x rx %llu/%llu/%llu rx %llu/%llu/%llu\n", 140 tunnel->debug, 141 (unsigned long long)tunnel->stats.tx_packets, 142 (unsigned long long)tunnel->stats.tx_bytes, 143 (unsigned long long)tunnel->stats.tx_errors, 144 (unsigned long long)tunnel->stats.rx_packets, 145 (unsigned long long)tunnel->stats.rx_bytes, 146 (unsigned long long)tunnel->stats.rx_errors); 147 148 if (tunnel->show != NULL) 149 tunnel->show(m, tunnel); 150 } 151 152 static void l2tp_dfs_seq_session_show(struct seq_file *m, void *v) 153 { 154 struct l2tp_session *session = v; 155 156 seq_printf(m, " SESSION %u, peer %u, %s\n", session->session_id, 157 session->peer_session_id, 158 session->pwtype == L2TP_PWTYPE_ETH ? "ETH" : 159 session->pwtype == L2TP_PWTYPE_PPP ? "PPP" : 160 ""); 161 if (session->send_seq || session->recv_seq) 162 seq_printf(m, " nr %hu, ns %hu\n", session->nr, session->ns); 163 seq_printf(m, " refcnt %d\n", atomic_read(&session->ref_count)); 164 seq_printf(m, " config %d/%d/%c/%c/%s/%s %08x %u\n", 165 session->mtu, session->mru, 166 session->recv_seq ? 'R' : '-', 167 session->send_seq ? 'S' : '-', 168 session->data_seq == 1 ? "IPSEQ" : 169 session->data_seq == 2 ? "DATASEQ" : "-", 170 session->lns_mode ? "LNS" : "LAC", 171 session->debug, 172 jiffies_to_msecs(session->reorder_timeout)); 173 seq_printf(m, " offset %hu l2specific %hu/%hu\n", 174 session->offset, session->l2specific_type, session->l2specific_len); 175 if (session->cookie_len) { 176 seq_printf(m, " cookie %02x%02x%02x%02x", 177 session->cookie[0], session->cookie[1], 178 session->cookie[2], session->cookie[3]); 179 if (session->cookie_len == 8) 180 seq_printf(m, "%02x%02x%02x%02x", 181 session->cookie[4], session->cookie[5], 182 session->cookie[6], session->cookie[7]); 183 seq_printf(m, "\n"); 184 } 185 if (session->peer_cookie_len) { 186 seq_printf(m, " peer cookie %02x%02x%02x%02x", 187 session->peer_cookie[0], session->peer_cookie[1], 188 session->peer_cookie[2], session->peer_cookie[3]); 189 if (session->peer_cookie_len == 8) 190 seq_printf(m, "%02x%02x%02x%02x", 191 session->peer_cookie[4], session->peer_cookie[5], 192 session->peer_cookie[6], session->peer_cookie[7]); 193 seq_printf(m, "\n"); 194 } 195 196 seq_printf(m, " %hu/%hu tx %llu/%llu/%llu rx %llu/%llu/%llu\n", 197 session->nr, session->ns, 198 (unsigned long long)session->stats.tx_packets, 199 (unsigned long long)session->stats.tx_bytes, 200 (unsigned long long)session->stats.tx_errors, 201 (unsigned long long)session->stats.rx_packets, 202 (unsigned long long)session->stats.rx_bytes, 203 (unsigned long long)session->stats.rx_errors); 204 205 if (session->show != NULL) 206 session->show(m, session); 207 } 208 209 static int l2tp_dfs_seq_show(struct seq_file *m, void *v) 210 { 211 struct l2tp_dfs_seq_data *pd = v; 212 213 /* display header on line 1 */ 214 if (v == SEQ_START_TOKEN) { 215 seq_puts(m, "TUNNEL ID, peer ID from IP to IP\n"); 216 seq_puts(m, " L2TPv2/L2TPv3, UDP/IP\n"); 217 seq_puts(m, " sessions session-count, refcnt refcnt/sk->refcnt\n"); 218 seq_puts(m, " debug tx-pkts/bytes/errs rx-pkts/bytes/errs\n"); 219 seq_puts(m, " SESSION ID, peer ID, PWTYPE\n"); 220 seq_puts(m, " refcnt cnt\n"); 221 seq_puts(m, " offset OFFSET l2specific TYPE/LEN\n"); 222 seq_puts(m, " [ cookie ]\n"); 223 seq_puts(m, " [ peer cookie ]\n"); 224 seq_puts(m, " config mtu/mru/rcvseq/sendseq/dataseq/lns debug reorderto\n"); 225 seq_puts(m, " nr/ns tx-pkts/bytes/errs rx-pkts/bytes/errs\n"); 226 goto out; 227 } 228 229 /* Show the tunnel or session context */ 230 if (pd->session == NULL) 231 l2tp_dfs_seq_tunnel_show(m, pd->tunnel); 232 else 233 l2tp_dfs_seq_session_show(m, pd->session); 234 235 out: 236 return 0; 237 } 238 239 static const struct seq_operations l2tp_dfs_seq_ops = { 240 .start = l2tp_dfs_seq_start, 241 .next = l2tp_dfs_seq_next, 242 .stop = l2tp_dfs_seq_stop, 243 .show = l2tp_dfs_seq_show, 244 }; 245 246 static int l2tp_dfs_seq_open(struct inode *inode, struct file *file) 247 { 248 struct l2tp_dfs_seq_data *pd; 249 struct seq_file *seq; 250 int rc = -ENOMEM; 251 252 pd = kzalloc(GFP_KERNEL, sizeof(*pd)); 253 if (pd == NULL) 254 goto out; 255 256 /* Derive the network namespace from the pid opening the 257 * file. 258 */ 259 pd->net = get_net_ns_by_pid(current->pid); 260 if (IS_ERR(pd->net)) { 261 rc = -PTR_ERR(pd->net); 262 goto err_free_pd; 263 } 264 265 rc = seq_open(file, &l2tp_dfs_seq_ops); 266 if (rc) 267 goto err_free_net; 268 269 seq = file->private_data; 270 seq->private = pd; 271 272 out: 273 return rc; 274 275 err_free_net: 276 put_net(pd->net); 277 err_free_pd: 278 kfree(pd); 279 goto out; 280 } 281 282 static int l2tp_dfs_seq_release(struct inode *inode, struct file *file) 283 { 284 struct l2tp_dfs_seq_data *pd; 285 struct seq_file *seq; 286 287 seq = file->private_data; 288 pd = seq->private; 289 if (pd->net) 290 put_net(pd->net); 291 kfree(pd); 292 seq_release(inode, file); 293 294 return 0; 295 } 296 297 static const struct file_operations l2tp_dfs_fops = { 298 .owner = THIS_MODULE, 299 .open = l2tp_dfs_seq_open, 300 .read = seq_read, 301 .llseek = seq_lseek, 302 .release = l2tp_dfs_seq_release, 303 }; 304 305 static int __init l2tp_debugfs_init(void) 306 { 307 int rc = 0; 308 309 rootdir = debugfs_create_dir("l2tp", NULL); 310 if (IS_ERR(rootdir)) { 311 rc = PTR_ERR(rootdir); 312 rootdir = NULL; 313 goto out; 314 } 315 316 tunnels = debugfs_create_file("tunnels", 0600, rootdir, NULL, &l2tp_dfs_fops); 317 if (tunnels == NULL) 318 rc = -EIO; 319 320 printk(KERN_INFO "L2TP debugfs support\n"); 321 322 out: 323 if (rc) 324 printk(KERN_WARNING "l2tp debugfs: unable to init\n"); 325 326 return rc; 327 } 328 329 static void __exit l2tp_debugfs_exit(void) 330 { 331 debugfs_remove(tunnels); 332 debugfs_remove(rootdir); 333 } 334 335 module_init(l2tp_debugfs_init); 336 module_exit(l2tp_debugfs_exit); 337 338 MODULE_LICENSE("GPL"); 339 MODULE_AUTHOR("James Chapman <jchapman@katalix.com>"); 340 MODULE_DESCRIPTION("L2TP debugfs driver"); 341 MODULE_VERSION("1.0"); 342