James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1 | /* |
| 2 | * L2TP core. |
| 3 | * |
| 4 | * Copyright (c) 2008,2009,2010 Katalix Systems Ltd |
| 5 | * |
| 6 | * This file contains some code of the original L2TPv2 pppol2tp |
| 7 | * driver, which has the following copyright: |
| 8 | * |
| 9 | * Authors: Martijn van Oosterhout <kleptog@svana.org> |
| 10 | * James Chapman (jchapman@katalix.com) |
| 11 | * Contributors: |
| 12 | * Michal Ostrowski <mostrows@speakeasy.net> |
| 13 | * Arnaldo Carvalho de Melo <acme@xconectiva.com.br> |
| 14 | * David S. Miller (davem@redhat.com) |
| 15 | * |
| 16 | * This program is free software; you can redistribute it and/or modify |
| 17 | * it under the terms of the GNU General Public License version 2 as |
| 18 | * published by the Free Software Foundation. |
| 19 | */ |
| 20 | |
| 21 | #include <linux/module.h> |
| 22 | #include <linux/string.h> |
| 23 | #include <linux/list.h> |
James Chapman | e02d494 | 2010-04-02 06:19:16 +0000 | [diff] [blame] | 24 | #include <linux/rculist.h> |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 25 | #include <linux/uaccess.h> |
| 26 | |
| 27 | #include <linux/kernel.h> |
| 28 | #include <linux/spinlock.h> |
| 29 | #include <linux/kthread.h> |
| 30 | #include <linux/sched.h> |
| 31 | #include <linux/slab.h> |
| 32 | #include <linux/errno.h> |
| 33 | #include <linux/jiffies.h> |
| 34 | |
| 35 | #include <linux/netdevice.h> |
| 36 | #include <linux/net.h> |
| 37 | #include <linux/inetdevice.h> |
| 38 | #include <linux/skbuff.h> |
| 39 | #include <linux/init.h> |
James Chapman | 0d76751 | 2010-04-02 06:19:00 +0000 | [diff] [blame] | 40 | #include <linux/in.h> |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 41 | #include <linux/ip.h> |
| 42 | #include <linux/udp.h> |
James Chapman | 0d76751 | 2010-04-02 06:19:00 +0000 | [diff] [blame] | 43 | #include <linux/l2tp.h> |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 44 | #include <linux/hash.h> |
| 45 | #include <linux/sort.h> |
| 46 | #include <linux/file.h> |
| 47 | #include <linux/nsproxy.h> |
| 48 | #include <net/net_namespace.h> |
| 49 | #include <net/netns/generic.h> |
| 50 | #include <net/dst.h> |
| 51 | #include <net/ip.h> |
| 52 | #include <net/udp.h> |
James Chapman | 309795f | 2010-04-02 06:19:10 +0000 | [diff] [blame] | 53 | #include <net/inet_common.h> |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 54 | #include <net/xfrm.h> |
James Chapman | 0d76751 | 2010-04-02 06:19:00 +0000 | [diff] [blame] | 55 | #include <net/protocol.h> |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 56 | |
| 57 | #include <asm/byteorder.h> |
| 58 | #include <asm/atomic.h> |
| 59 | |
| 60 | #include "l2tp_core.h" |
| 61 | |
| 62 | #define L2TP_DRV_VERSION "V2.0" |
| 63 | |
| 64 | /* L2TP header constants */ |
| 65 | #define L2TP_HDRFLAG_T 0x8000 |
| 66 | #define L2TP_HDRFLAG_L 0x4000 |
| 67 | #define L2TP_HDRFLAG_S 0x0800 |
| 68 | #define L2TP_HDRFLAG_O 0x0200 |
| 69 | #define L2TP_HDRFLAG_P 0x0100 |
| 70 | |
| 71 | #define L2TP_HDR_VER_MASK 0x000F |
| 72 | #define L2TP_HDR_VER_2 0x0002 |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 73 | #define L2TP_HDR_VER_3 0x0003 |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 74 | |
| 75 | /* L2TPv3 default L2-specific sublayer */ |
| 76 | #define L2TP_SLFLAG_S 0x40000000 |
| 77 | #define L2TP_SL_SEQ_MASK 0x00ffffff |
| 78 | |
| 79 | #define L2TP_HDR_SIZE_SEQ 10 |
| 80 | #define L2TP_HDR_SIZE_NOSEQ 6 |
| 81 | |
| 82 | /* Default trace flags */ |
| 83 | #define L2TP_DEFAULT_DEBUG_FLAGS 0 |
| 84 | |
| 85 | #define PRINTK(_mask, _type, _lvl, _fmt, args...) \ |
| 86 | do { \ |
| 87 | if ((_mask) & (_type)) \ |
| 88 | printk(_lvl "L2TP: " _fmt, ##args); \ |
| 89 | } while (0) |
| 90 | |
| 91 | /* Private data stored for received packets in the skb. |
| 92 | */ |
| 93 | struct l2tp_skb_cb { |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 94 | u32 ns; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 95 | u16 has_seq; |
| 96 | u16 length; |
| 97 | unsigned long expires; |
| 98 | }; |
| 99 | |
| 100 | #define L2TP_SKB_CB(skb) ((struct l2tp_skb_cb *) &skb->cb[sizeof(struct inet_skb_parm)]) |
| 101 | |
| 102 | static atomic_t l2tp_tunnel_count; |
| 103 | static atomic_t l2tp_session_count; |
| 104 | |
| 105 | /* per-net private data for this module */ |
| 106 | static unsigned int l2tp_net_id; |
| 107 | struct l2tp_net { |
| 108 | struct list_head l2tp_tunnel_list; |
James Chapman | e02d494 | 2010-04-02 06:19:16 +0000 | [diff] [blame] | 109 | spinlock_t l2tp_tunnel_list_lock; |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 110 | struct hlist_head l2tp_session_hlist[L2TP_HASH_SIZE_2]; |
James Chapman | e02d494 | 2010-04-02 06:19:16 +0000 | [diff] [blame] | 111 | spinlock_t l2tp_session_hlist_lock; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 112 | }; |
| 113 | |
| 114 | static inline struct l2tp_net *l2tp_pernet(struct net *net) |
| 115 | { |
| 116 | BUG_ON(!net); |
| 117 | |
| 118 | return net_generic(net, l2tp_net_id); |
| 119 | } |
| 120 | |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 121 | /* Session hash global list for L2TPv3. |
| 122 | * The session_id SHOULD be random according to RFC3931, but several |
| 123 | * L2TP implementations use incrementing session_ids. So we do a real |
| 124 | * hash on the session_id, rather than a simple bitmask. |
| 125 | */ |
| 126 | static inline struct hlist_head * |
| 127 | l2tp_session_id_hash_2(struct l2tp_net *pn, u32 session_id) |
| 128 | { |
| 129 | return &pn->l2tp_session_hlist[hash_32(session_id, L2TP_HASH_BITS_2)]; |
| 130 | |
| 131 | } |
| 132 | |
| 133 | /* Lookup a session by id in the global session list |
| 134 | */ |
| 135 | static struct l2tp_session *l2tp_session_find_2(struct net *net, u32 session_id) |
| 136 | { |
| 137 | struct l2tp_net *pn = l2tp_pernet(net); |
| 138 | struct hlist_head *session_list = |
| 139 | l2tp_session_id_hash_2(pn, session_id); |
| 140 | struct l2tp_session *session; |
| 141 | struct hlist_node *walk; |
| 142 | |
James Chapman | e02d494 | 2010-04-02 06:19:16 +0000 | [diff] [blame] | 143 | rcu_read_lock_bh(); |
| 144 | hlist_for_each_entry_rcu(session, walk, session_list, global_hlist) { |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 145 | if (session->session_id == session_id) { |
James Chapman | e02d494 | 2010-04-02 06:19:16 +0000 | [diff] [blame] | 146 | rcu_read_unlock_bh(); |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 147 | return session; |
| 148 | } |
| 149 | } |
James Chapman | e02d494 | 2010-04-02 06:19:16 +0000 | [diff] [blame] | 150 | rcu_read_unlock_bh(); |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 151 | |
| 152 | return NULL; |
| 153 | } |
| 154 | |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 155 | /* Session hash list. |
| 156 | * The session_id SHOULD be random according to RFC2661, but several |
| 157 | * L2TP implementations (Cisco and Microsoft) use incrementing |
| 158 | * session_ids. So we do a real hash on the session_id, rather than a |
| 159 | * simple bitmask. |
| 160 | */ |
| 161 | static inline struct hlist_head * |
| 162 | l2tp_session_id_hash(struct l2tp_tunnel *tunnel, u32 session_id) |
| 163 | { |
| 164 | return &tunnel->session_hlist[hash_32(session_id, L2TP_HASH_BITS)]; |
| 165 | } |
| 166 | |
| 167 | /* Lookup a session by id |
| 168 | */ |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 169 | struct l2tp_session *l2tp_session_find(struct net *net, struct l2tp_tunnel *tunnel, u32 session_id) |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 170 | { |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 171 | struct hlist_head *session_list; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 172 | struct l2tp_session *session; |
| 173 | struct hlist_node *walk; |
| 174 | |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 175 | /* In L2TPv3, session_ids are unique over all tunnels and we |
| 176 | * sometimes need to look them up before we know the |
| 177 | * tunnel. |
| 178 | */ |
| 179 | if (tunnel == NULL) |
| 180 | return l2tp_session_find_2(net, session_id); |
| 181 | |
| 182 | session_list = l2tp_session_id_hash(tunnel, session_id); |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 183 | read_lock_bh(&tunnel->hlist_lock); |
| 184 | hlist_for_each_entry(session, walk, session_list, hlist) { |
| 185 | if (session->session_id == session_id) { |
| 186 | read_unlock_bh(&tunnel->hlist_lock); |
| 187 | return session; |
| 188 | } |
| 189 | } |
| 190 | read_unlock_bh(&tunnel->hlist_lock); |
| 191 | |
| 192 | return NULL; |
| 193 | } |
| 194 | EXPORT_SYMBOL_GPL(l2tp_session_find); |
| 195 | |
| 196 | struct l2tp_session *l2tp_session_find_nth(struct l2tp_tunnel *tunnel, int nth) |
| 197 | { |
| 198 | int hash; |
| 199 | struct hlist_node *walk; |
| 200 | struct l2tp_session *session; |
| 201 | int count = 0; |
| 202 | |
| 203 | read_lock_bh(&tunnel->hlist_lock); |
| 204 | for (hash = 0; hash < L2TP_HASH_SIZE; hash++) { |
| 205 | hlist_for_each_entry(session, walk, &tunnel->session_hlist[hash], hlist) { |
| 206 | if (++count > nth) { |
| 207 | read_unlock_bh(&tunnel->hlist_lock); |
| 208 | return session; |
| 209 | } |
| 210 | } |
| 211 | } |
| 212 | |
| 213 | read_unlock_bh(&tunnel->hlist_lock); |
| 214 | |
| 215 | return NULL; |
| 216 | } |
| 217 | EXPORT_SYMBOL_GPL(l2tp_session_find_nth); |
| 218 | |
James Chapman | 309795f | 2010-04-02 06:19:10 +0000 | [diff] [blame] | 219 | /* Lookup a session by interface name. |
| 220 | * This is very inefficient but is only used by management interfaces. |
| 221 | */ |
| 222 | struct l2tp_session *l2tp_session_find_by_ifname(struct net *net, char *ifname) |
| 223 | { |
| 224 | struct l2tp_net *pn = l2tp_pernet(net); |
| 225 | int hash; |
| 226 | struct hlist_node *walk; |
| 227 | struct l2tp_session *session; |
| 228 | |
James Chapman | e02d494 | 2010-04-02 06:19:16 +0000 | [diff] [blame] | 229 | rcu_read_lock_bh(); |
James Chapman | 309795f | 2010-04-02 06:19:10 +0000 | [diff] [blame] | 230 | for (hash = 0; hash < L2TP_HASH_SIZE_2; hash++) { |
James Chapman | e02d494 | 2010-04-02 06:19:16 +0000 | [diff] [blame] | 231 | hlist_for_each_entry_rcu(session, walk, &pn->l2tp_session_hlist[hash], global_hlist) { |
James Chapman | 309795f | 2010-04-02 06:19:10 +0000 | [diff] [blame] | 232 | if (!strcmp(session->ifname, ifname)) { |
James Chapman | e02d494 | 2010-04-02 06:19:16 +0000 | [diff] [blame] | 233 | rcu_read_unlock_bh(); |
James Chapman | 309795f | 2010-04-02 06:19:10 +0000 | [diff] [blame] | 234 | return session; |
| 235 | } |
| 236 | } |
| 237 | } |
| 238 | |
James Chapman | e02d494 | 2010-04-02 06:19:16 +0000 | [diff] [blame] | 239 | rcu_read_unlock_bh(); |
James Chapman | 309795f | 2010-04-02 06:19:10 +0000 | [diff] [blame] | 240 | |
| 241 | return NULL; |
| 242 | } |
| 243 | EXPORT_SYMBOL_GPL(l2tp_session_find_by_ifname); |
| 244 | |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 245 | /* Lookup a tunnel by id |
| 246 | */ |
| 247 | struct l2tp_tunnel *l2tp_tunnel_find(struct net *net, u32 tunnel_id) |
| 248 | { |
| 249 | struct l2tp_tunnel *tunnel; |
| 250 | struct l2tp_net *pn = l2tp_pernet(net); |
| 251 | |
James Chapman | e02d494 | 2010-04-02 06:19:16 +0000 | [diff] [blame] | 252 | rcu_read_lock_bh(); |
| 253 | list_for_each_entry_rcu(tunnel, &pn->l2tp_tunnel_list, list) { |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 254 | if (tunnel->tunnel_id == tunnel_id) { |
James Chapman | e02d494 | 2010-04-02 06:19:16 +0000 | [diff] [blame] | 255 | rcu_read_unlock_bh(); |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 256 | return tunnel; |
| 257 | } |
| 258 | } |
James Chapman | e02d494 | 2010-04-02 06:19:16 +0000 | [diff] [blame] | 259 | rcu_read_unlock_bh(); |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 260 | |
| 261 | return NULL; |
| 262 | } |
| 263 | EXPORT_SYMBOL_GPL(l2tp_tunnel_find); |
| 264 | |
| 265 | struct l2tp_tunnel *l2tp_tunnel_find_nth(struct net *net, int nth) |
| 266 | { |
| 267 | struct l2tp_net *pn = l2tp_pernet(net); |
| 268 | struct l2tp_tunnel *tunnel; |
| 269 | int count = 0; |
| 270 | |
James Chapman | e02d494 | 2010-04-02 06:19:16 +0000 | [diff] [blame] | 271 | rcu_read_lock_bh(); |
| 272 | list_for_each_entry_rcu(tunnel, &pn->l2tp_tunnel_list, list) { |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 273 | if (++count > nth) { |
James Chapman | e02d494 | 2010-04-02 06:19:16 +0000 | [diff] [blame] | 274 | rcu_read_unlock_bh(); |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 275 | return tunnel; |
| 276 | } |
| 277 | } |
| 278 | |
James Chapman | e02d494 | 2010-04-02 06:19:16 +0000 | [diff] [blame] | 279 | rcu_read_unlock_bh(); |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 280 | |
| 281 | return NULL; |
| 282 | } |
| 283 | EXPORT_SYMBOL_GPL(l2tp_tunnel_find_nth); |
| 284 | |
| 285 | /***************************************************************************** |
| 286 | * Receive data handling |
| 287 | *****************************************************************************/ |
| 288 | |
| 289 | /* Queue a skb in order. We come here only if the skb has an L2TP sequence |
| 290 | * number. |
| 291 | */ |
| 292 | static void l2tp_recv_queue_skb(struct l2tp_session *session, struct sk_buff *skb) |
| 293 | { |
| 294 | struct sk_buff *skbp; |
| 295 | struct sk_buff *tmp; |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 296 | u32 ns = L2TP_SKB_CB(skb)->ns; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 297 | |
| 298 | spin_lock_bh(&session->reorder_q.lock); |
| 299 | skb_queue_walk_safe(&session->reorder_q, skbp, tmp) { |
| 300 | if (L2TP_SKB_CB(skbp)->ns > ns) { |
| 301 | __skb_queue_before(&session->reorder_q, skbp, skb); |
| 302 | PRINTK(session->debug, L2TP_MSG_SEQ, KERN_DEBUG, |
| 303 | "%s: pkt %hu, inserted before %hu, reorder_q len=%d\n", |
| 304 | session->name, ns, L2TP_SKB_CB(skbp)->ns, |
| 305 | skb_queue_len(&session->reorder_q)); |
| 306 | session->stats.rx_oos_packets++; |
| 307 | goto out; |
| 308 | } |
| 309 | } |
| 310 | |
| 311 | __skb_queue_tail(&session->reorder_q, skb); |
| 312 | |
| 313 | out: |
| 314 | spin_unlock_bh(&session->reorder_q.lock); |
| 315 | } |
| 316 | |
| 317 | /* Dequeue a single skb. |
| 318 | */ |
| 319 | static void l2tp_recv_dequeue_skb(struct l2tp_session *session, struct sk_buff *skb) |
| 320 | { |
| 321 | struct l2tp_tunnel *tunnel = session->tunnel; |
| 322 | int length = L2TP_SKB_CB(skb)->length; |
| 323 | |
| 324 | /* We're about to requeue the skb, so return resources |
| 325 | * to its current owner (a socket receive buffer). |
| 326 | */ |
| 327 | skb_orphan(skb); |
| 328 | |
| 329 | tunnel->stats.rx_packets++; |
| 330 | tunnel->stats.rx_bytes += length; |
| 331 | session->stats.rx_packets++; |
| 332 | session->stats.rx_bytes += length; |
| 333 | |
| 334 | if (L2TP_SKB_CB(skb)->has_seq) { |
| 335 | /* Bump our Nr */ |
| 336 | session->nr++; |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 337 | if (tunnel->version == L2TP_HDR_VER_2) |
| 338 | session->nr &= 0xffff; |
| 339 | else |
| 340 | session->nr &= 0xffffff; |
| 341 | |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 342 | PRINTK(session->debug, L2TP_MSG_SEQ, KERN_DEBUG, |
| 343 | "%s: updated nr to %hu\n", session->name, session->nr); |
| 344 | } |
| 345 | |
| 346 | /* call private receive handler */ |
| 347 | if (session->recv_skb != NULL) |
| 348 | (*session->recv_skb)(session, skb, L2TP_SKB_CB(skb)->length); |
| 349 | else |
| 350 | kfree_skb(skb); |
| 351 | |
| 352 | if (session->deref) |
| 353 | (*session->deref)(session); |
| 354 | } |
| 355 | |
| 356 | /* Dequeue skbs from the session's reorder_q, subject to packet order. |
| 357 | * Skbs that have been in the queue for too long are simply discarded. |
| 358 | */ |
| 359 | static void l2tp_recv_dequeue(struct l2tp_session *session) |
| 360 | { |
| 361 | struct sk_buff *skb; |
| 362 | struct sk_buff *tmp; |
| 363 | |
| 364 | /* If the pkt at the head of the queue has the nr that we |
| 365 | * expect to send up next, dequeue it and any other |
| 366 | * in-sequence packets behind it. |
| 367 | */ |
| 368 | spin_lock_bh(&session->reorder_q.lock); |
| 369 | skb_queue_walk_safe(&session->reorder_q, skb, tmp) { |
| 370 | if (time_after(jiffies, L2TP_SKB_CB(skb)->expires)) { |
| 371 | session->stats.rx_seq_discards++; |
| 372 | session->stats.rx_errors++; |
| 373 | PRINTK(session->debug, L2TP_MSG_SEQ, KERN_DEBUG, |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 374 | "%s: oos pkt %u len %d discarded (too old), " |
| 375 | "waiting for %u, reorder_q_len=%d\n", |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 376 | session->name, L2TP_SKB_CB(skb)->ns, |
| 377 | L2TP_SKB_CB(skb)->length, session->nr, |
| 378 | skb_queue_len(&session->reorder_q)); |
| 379 | __skb_unlink(skb, &session->reorder_q); |
| 380 | kfree_skb(skb); |
| 381 | if (session->deref) |
| 382 | (*session->deref)(session); |
| 383 | continue; |
| 384 | } |
| 385 | |
| 386 | if (L2TP_SKB_CB(skb)->has_seq) { |
| 387 | if (L2TP_SKB_CB(skb)->ns != session->nr) { |
| 388 | PRINTK(session->debug, L2TP_MSG_SEQ, KERN_DEBUG, |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 389 | "%s: holding oos pkt %u len %d, " |
| 390 | "waiting for %u, reorder_q_len=%d\n", |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 391 | session->name, L2TP_SKB_CB(skb)->ns, |
| 392 | L2TP_SKB_CB(skb)->length, session->nr, |
| 393 | skb_queue_len(&session->reorder_q)); |
| 394 | goto out; |
| 395 | } |
| 396 | } |
| 397 | __skb_unlink(skb, &session->reorder_q); |
| 398 | |
| 399 | /* Process the skb. We release the queue lock while we |
| 400 | * do so to let other contexts process the queue. |
| 401 | */ |
| 402 | spin_unlock_bh(&session->reorder_q.lock); |
| 403 | l2tp_recv_dequeue_skb(session, skb); |
| 404 | spin_lock_bh(&session->reorder_q.lock); |
| 405 | } |
| 406 | |
| 407 | out: |
| 408 | spin_unlock_bh(&session->reorder_q.lock); |
| 409 | } |
| 410 | |
| 411 | static inline int l2tp_verify_udp_checksum(struct sock *sk, |
| 412 | struct sk_buff *skb) |
| 413 | { |
| 414 | struct udphdr *uh = udp_hdr(skb); |
| 415 | u16 ulen = ntohs(uh->len); |
| 416 | struct inet_sock *inet; |
| 417 | __wsum psum; |
| 418 | |
| 419 | if (sk->sk_no_check || skb_csum_unnecessary(skb) || !uh->check) |
| 420 | return 0; |
| 421 | |
| 422 | inet = inet_sk(sk); |
| 423 | psum = csum_tcpudp_nofold(inet->inet_saddr, inet->inet_daddr, ulen, |
| 424 | IPPROTO_UDP, 0); |
| 425 | |
| 426 | if ((skb->ip_summed == CHECKSUM_COMPLETE) && |
| 427 | !csum_fold(csum_add(psum, skb->csum))) |
| 428 | return 0; |
| 429 | |
| 430 | skb->csum = psum; |
| 431 | |
| 432 | return __skb_checksum_complete(skb); |
| 433 | } |
| 434 | |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 435 | /* Do receive processing of L2TP data frames. We handle both L2TPv2 |
| 436 | * and L2TPv3 data frames here. |
| 437 | * |
| 438 | * L2TPv2 Data Message Header |
| 439 | * |
| 440 | * 0 1 2 3 |
| 441 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 |
| 442 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 443 | * |T|L|x|x|S|x|O|P|x|x|x|x| Ver | Length (opt) | |
| 444 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 445 | * | Tunnel ID | Session ID | |
| 446 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 447 | * | Ns (opt) | Nr (opt) | |
| 448 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 449 | * | Offset Size (opt) | Offset pad... (opt) |
| 450 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 451 | * |
| 452 | * Data frames are marked by T=0. All other fields are the same as |
| 453 | * those in L2TP control frames. |
| 454 | * |
| 455 | * L2TPv3 Data Message Header |
| 456 | * |
| 457 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 458 | * | L2TP Session Header | |
| 459 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 460 | * | L2-Specific Sublayer | |
| 461 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 462 | * | Tunnel Payload ... |
| 463 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 464 | * |
| 465 | * L2TPv3 Session Header Over IP |
| 466 | * |
| 467 | * 0 1 2 3 |
| 468 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 |
| 469 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 470 | * | Session ID | |
| 471 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 472 | * | Cookie (optional, maximum 64 bits)... |
| 473 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 474 | * | |
| 475 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 476 | * |
| 477 | * L2TPv3 L2-Specific Sublayer Format |
| 478 | * |
| 479 | * 0 1 2 3 |
| 480 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 |
| 481 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 482 | * |x|S|x|x|x|x|x|x| Sequence Number | |
| 483 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 484 | * |
| 485 | * Cookie value, sublayer format and offset (pad) are negotiated with |
| 486 | * the peer when the session is set up. Unlike L2TPv2, we do not need |
| 487 | * to parse the packet header to determine if optional fields are |
| 488 | * present. |
| 489 | * |
| 490 | * Caller must already have parsed the frame and determined that it is |
| 491 | * a data (not control) frame before coming here. Fields up to the |
| 492 | * session-id have already been parsed and ptr points to the data |
| 493 | * after the session-id. |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 494 | */ |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 495 | void l2tp_recv_common(struct l2tp_session *session, struct sk_buff *skb, |
| 496 | unsigned char *ptr, unsigned char *optr, u16 hdrflags, |
| 497 | int length, int (*payload_hook)(struct sk_buff *skb)) |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 498 | { |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 499 | struct l2tp_tunnel *tunnel = session->tunnel; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 500 | int offset; |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 501 | u32 ns, nr; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 502 | |
| 503 | /* The ref count is increased since we now hold a pointer to |
| 504 | * the session. Take care to decrement the refcnt when exiting |
| 505 | * this function from now on... |
| 506 | */ |
| 507 | l2tp_session_inc_refcount(session); |
| 508 | if (session->ref) |
| 509 | (*session->ref)(session); |
| 510 | |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 511 | /* Parse and check optional cookie */ |
| 512 | if (session->peer_cookie_len > 0) { |
| 513 | if (memcmp(ptr, &session->peer_cookie[0], session->peer_cookie_len)) { |
| 514 | PRINTK(tunnel->debug, L2TP_MSG_DATA, KERN_INFO, |
| 515 | "%s: cookie mismatch (%u/%u). Discarding.\n", |
| 516 | tunnel->name, tunnel->tunnel_id, session->session_id); |
| 517 | session->stats.rx_cookie_discards++; |
| 518 | goto discard; |
| 519 | } |
| 520 | ptr += session->peer_cookie_len; |
| 521 | } |
| 522 | |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 523 | /* Handle the optional sequence numbers. Sequence numbers are |
| 524 | * in different places for L2TPv2 and L2TPv3. |
| 525 | * |
| 526 | * If we are the LAC, enable/disable sequence numbers under |
| 527 | * the control of the LNS. If no sequence numbers present but |
| 528 | * we were expecting them, discard frame. |
| 529 | */ |
| 530 | ns = nr = 0; |
| 531 | L2TP_SKB_CB(skb)->has_seq = 0; |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 532 | if (tunnel->version == L2TP_HDR_VER_2) { |
| 533 | if (hdrflags & L2TP_HDRFLAG_S) { |
| 534 | ns = ntohs(*(__be16 *) ptr); |
| 535 | ptr += 2; |
| 536 | nr = ntohs(*(__be16 *) ptr); |
| 537 | ptr += 2; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 538 | |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 539 | /* Store L2TP info in the skb */ |
| 540 | L2TP_SKB_CB(skb)->ns = ns; |
| 541 | L2TP_SKB_CB(skb)->has_seq = 1; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 542 | |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 543 | PRINTK(session->debug, L2TP_MSG_SEQ, KERN_DEBUG, |
| 544 | "%s: recv data ns=%u, nr=%u, session nr=%u\n", |
| 545 | session->name, ns, nr, session->nr); |
| 546 | } |
| 547 | } else if (session->l2specific_type == L2TP_L2SPECTYPE_DEFAULT) { |
| 548 | u32 l2h = ntohl(*(__be32 *) ptr); |
| 549 | |
| 550 | if (l2h & 0x40000000) { |
| 551 | ns = l2h & 0x00ffffff; |
| 552 | |
| 553 | /* Store L2TP info in the skb */ |
| 554 | L2TP_SKB_CB(skb)->ns = ns; |
| 555 | L2TP_SKB_CB(skb)->has_seq = 1; |
| 556 | |
| 557 | PRINTK(session->debug, L2TP_MSG_SEQ, KERN_DEBUG, |
| 558 | "%s: recv data ns=%u, session nr=%u\n", |
| 559 | session->name, ns, session->nr); |
| 560 | } |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 561 | } |
| 562 | |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 563 | /* Advance past L2-specific header, if present */ |
| 564 | ptr += session->l2specific_len; |
| 565 | |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 566 | if (L2TP_SKB_CB(skb)->has_seq) { |
| 567 | /* Received a packet with sequence numbers. If we're the LNS, |
| 568 | * check if we sre sending sequence numbers and if not, |
| 569 | * configure it so. |
| 570 | */ |
| 571 | if ((!session->lns_mode) && (!session->send_seq)) { |
| 572 | PRINTK(session->debug, L2TP_MSG_SEQ, KERN_INFO, |
| 573 | "%s: requested to enable seq numbers by LNS\n", |
| 574 | session->name); |
| 575 | session->send_seq = -1; |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 576 | l2tp_session_set_header_len(session, tunnel->version); |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 577 | } |
| 578 | } else { |
| 579 | /* No sequence numbers. |
| 580 | * If user has configured mandatory sequence numbers, discard. |
| 581 | */ |
| 582 | if (session->recv_seq) { |
| 583 | PRINTK(session->debug, L2TP_MSG_SEQ, KERN_WARNING, |
| 584 | "%s: recv data has no seq numbers when required. " |
| 585 | "Discarding\n", session->name); |
| 586 | session->stats.rx_seq_discards++; |
| 587 | goto discard; |
| 588 | } |
| 589 | |
| 590 | /* If we're the LAC and we're sending sequence numbers, the |
| 591 | * LNS has requested that we no longer send sequence numbers. |
| 592 | * If we're the LNS and we're sending sequence numbers, the |
| 593 | * LAC is broken. Discard the frame. |
| 594 | */ |
| 595 | if ((!session->lns_mode) && (session->send_seq)) { |
| 596 | PRINTK(session->debug, L2TP_MSG_SEQ, KERN_INFO, |
| 597 | "%s: requested to disable seq numbers by LNS\n", |
| 598 | session->name); |
| 599 | session->send_seq = 0; |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 600 | l2tp_session_set_header_len(session, tunnel->version); |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 601 | } else if (session->send_seq) { |
| 602 | PRINTK(session->debug, L2TP_MSG_SEQ, KERN_WARNING, |
| 603 | "%s: recv data has no seq numbers when required. " |
| 604 | "Discarding\n", session->name); |
| 605 | session->stats.rx_seq_discards++; |
| 606 | goto discard; |
| 607 | } |
| 608 | } |
| 609 | |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 610 | /* Session data offset is handled differently for L2TPv2 and |
| 611 | * L2TPv3. For L2TPv2, there is an optional 16-bit value in |
| 612 | * the header. For L2TPv3, the offset is negotiated using AVPs |
| 613 | * in the session setup control protocol. |
| 614 | */ |
| 615 | if (tunnel->version == L2TP_HDR_VER_2) { |
| 616 | /* If offset bit set, skip it. */ |
| 617 | if (hdrflags & L2TP_HDRFLAG_O) { |
| 618 | offset = ntohs(*(__be16 *)ptr); |
| 619 | ptr += 2 + offset; |
| 620 | } |
| 621 | } else |
| 622 | ptr += session->offset; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 623 | |
| 624 | offset = ptr - optr; |
| 625 | if (!pskb_may_pull(skb, offset)) |
| 626 | goto discard; |
| 627 | |
| 628 | __skb_pull(skb, offset); |
| 629 | |
| 630 | /* If caller wants to process the payload before we queue the |
| 631 | * packet, do so now. |
| 632 | */ |
| 633 | if (payload_hook) |
| 634 | if ((*payload_hook)(skb)) |
| 635 | goto discard; |
| 636 | |
| 637 | /* Prepare skb for adding to the session's reorder_q. Hold |
| 638 | * packets for max reorder_timeout or 1 second if not |
| 639 | * reordering. |
| 640 | */ |
| 641 | L2TP_SKB_CB(skb)->length = length; |
| 642 | L2TP_SKB_CB(skb)->expires = jiffies + |
| 643 | (session->reorder_timeout ? session->reorder_timeout : HZ); |
| 644 | |
| 645 | /* Add packet to the session's receive queue. Reordering is done here, if |
| 646 | * enabled. Saved L2TP protocol info is stored in skb->sb[]. |
| 647 | */ |
| 648 | if (L2TP_SKB_CB(skb)->has_seq) { |
| 649 | if (session->reorder_timeout != 0) { |
| 650 | /* Packet reordering enabled. Add skb to session's |
| 651 | * reorder queue, in order of ns. |
| 652 | */ |
| 653 | l2tp_recv_queue_skb(session, skb); |
| 654 | } else { |
| 655 | /* Packet reordering disabled. Discard out-of-sequence |
| 656 | * packets |
| 657 | */ |
| 658 | if (L2TP_SKB_CB(skb)->ns != session->nr) { |
| 659 | session->stats.rx_seq_discards++; |
| 660 | PRINTK(session->debug, L2TP_MSG_SEQ, KERN_DEBUG, |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 661 | "%s: oos pkt %u len %d discarded, " |
| 662 | "waiting for %u, reorder_q_len=%d\n", |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 663 | session->name, L2TP_SKB_CB(skb)->ns, |
| 664 | L2TP_SKB_CB(skb)->length, session->nr, |
| 665 | skb_queue_len(&session->reorder_q)); |
| 666 | goto discard; |
| 667 | } |
| 668 | skb_queue_tail(&session->reorder_q, skb); |
| 669 | } |
| 670 | } else { |
| 671 | /* No sequence numbers. Add the skb to the tail of the |
| 672 | * reorder queue. This ensures that it will be |
| 673 | * delivered after all previous sequenced skbs. |
| 674 | */ |
| 675 | skb_queue_tail(&session->reorder_q, skb); |
| 676 | } |
| 677 | |
| 678 | /* Try to dequeue as many skbs from reorder_q as we can. */ |
| 679 | l2tp_recv_dequeue(session); |
| 680 | |
| 681 | l2tp_session_dec_refcount(session); |
| 682 | |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 683 | return; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 684 | |
| 685 | discard: |
| 686 | session->stats.rx_errors++; |
| 687 | kfree_skb(skb); |
| 688 | |
| 689 | if (session->deref) |
| 690 | (*session->deref)(session); |
| 691 | |
| 692 | l2tp_session_dec_refcount(session); |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 693 | } |
| 694 | EXPORT_SYMBOL(l2tp_recv_common); |
| 695 | |
| 696 | /* Internal UDP receive frame. Do the real work of receiving an L2TP data frame |
| 697 | * here. The skb is not on a list when we get here. |
| 698 | * Returns 0 if the packet was a data packet and was successfully passed on. |
| 699 | * Returns 1 if the packet was not a good data packet and could not be |
| 700 | * forwarded. All such packets are passed up to userspace to deal with. |
| 701 | */ |
| 702 | int l2tp_udp_recv_core(struct l2tp_tunnel *tunnel, struct sk_buff *skb, |
| 703 | int (*payload_hook)(struct sk_buff *skb)) |
| 704 | { |
| 705 | struct l2tp_session *session = NULL; |
| 706 | unsigned char *ptr, *optr; |
| 707 | u16 hdrflags; |
| 708 | u32 tunnel_id, session_id; |
| 709 | int offset; |
| 710 | u16 version; |
| 711 | int length; |
| 712 | |
| 713 | if (tunnel->sock && l2tp_verify_udp_checksum(tunnel->sock, skb)) |
| 714 | goto discard_bad_csum; |
| 715 | |
| 716 | /* UDP always verifies the packet length. */ |
| 717 | __skb_pull(skb, sizeof(struct udphdr)); |
| 718 | |
| 719 | /* Short packet? */ |
| 720 | if (!pskb_may_pull(skb, L2TP_HDR_SIZE_SEQ)) { |
| 721 | PRINTK(tunnel->debug, L2TP_MSG_DATA, KERN_INFO, |
| 722 | "%s: recv short packet (len=%d)\n", tunnel->name, skb->len); |
| 723 | goto error; |
| 724 | } |
| 725 | |
| 726 | /* Point to L2TP header */ |
| 727 | optr = ptr = skb->data; |
| 728 | |
| 729 | /* Trace packet contents, if enabled */ |
| 730 | if (tunnel->debug & L2TP_MSG_DATA) { |
| 731 | length = min(32u, skb->len); |
| 732 | if (!pskb_may_pull(skb, length)) |
| 733 | goto error; |
| 734 | |
| 735 | printk(KERN_DEBUG "%s: recv: ", tunnel->name); |
| 736 | |
| 737 | offset = 0; |
| 738 | do { |
| 739 | printk(" %02X", ptr[offset]); |
| 740 | } while (++offset < length); |
| 741 | |
| 742 | printk("\n"); |
| 743 | } |
| 744 | |
| 745 | /* Get L2TP header flags */ |
| 746 | hdrflags = ntohs(*(__be16 *) ptr); |
| 747 | |
| 748 | /* Check protocol version */ |
| 749 | version = hdrflags & L2TP_HDR_VER_MASK; |
| 750 | if (version != tunnel->version) { |
| 751 | PRINTK(tunnel->debug, L2TP_MSG_DATA, KERN_INFO, |
| 752 | "%s: recv protocol version mismatch: got %d expected %d\n", |
| 753 | tunnel->name, version, tunnel->version); |
| 754 | goto error; |
| 755 | } |
| 756 | |
| 757 | /* Get length of L2TP packet */ |
| 758 | length = skb->len; |
| 759 | |
| 760 | /* If type is control packet, it is handled by userspace. */ |
| 761 | if (hdrflags & L2TP_HDRFLAG_T) { |
| 762 | PRINTK(tunnel->debug, L2TP_MSG_DATA, KERN_DEBUG, |
| 763 | "%s: recv control packet, len=%d\n", tunnel->name, length); |
| 764 | goto error; |
| 765 | } |
| 766 | |
| 767 | /* Skip flags */ |
| 768 | ptr += 2; |
| 769 | |
| 770 | if (tunnel->version == L2TP_HDR_VER_2) { |
| 771 | /* If length is present, skip it */ |
| 772 | if (hdrflags & L2TP_HDRFLAG_L) |
| 773 | ptr += 2; |
| 774 | |
| 775 | /* Extract tunnel and session ID */ |
| 776 | tunnel_id = ntohs(*(__be16 *) ptr); |
| 777 | ptr += 2; |
| 778 | session_id = ntohs(*(__be16 *) ptr); |
| 779 | ptr += 2; |
| 780 | } else { |
| 781 | ptr += 2; /* skip reserved bits */ |
| 782 | tunnel_id = tunnel->tunnel_id; |
| 783 | session_id = ntohl(*(__be32 *) ptr); |
| 784 | ptr += 4; |
| 785 | } |
| 786 | |
| 787 | /* Find the session context */ |
| 788 | session = l2tp_session_find(tunnel->l2tp_net, tunnel, session_id); |
James Chapman | 309795f | 2010-04-02 06:19:10 +0000 | [diff] [blame] | 789 | if (!session || !session->recv_skb) { |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 790 | /* Not found? Pass to userspace to deal with */ |
| 791 | PRINTK(tunnel->debug, L2TP_MSG_DATA, KERN_INFO, |
| 792 | "%s: no session found (%u/%u). Passing up.\n", |
| 793 | tunnel->name, tunnel_id, session_id); |
| 794 | goto error; |
| 795 | } |
| 796 | |
| 797 | l2tp_recv_common(session, skb, ptr, optr, hdrflags, length, payload_hook); |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 798 | |
| 799 | return 0; |
| 800 | |
| 801 | discard_bad_csum: |
| 802 | LIMIT_NETDEBUG("%s: UDP: bad checksum\n", tunnel->name); |
| 803 | UDP_INC_STATS_USER(tunnel->l2tp_net, UDP_MIB_INERRORS, 0); |
| 804 | tunnel->stats.rx_errors++; |
| 805 | kfree_skb(skb); |
| 806 | |
| 807 | return 0; |
| 808 | |
| 809 | error: |
| 810 | /* Put UDP header back */ |
| 811 | __skb_push(skb, sizeof(struct udphdr)); |
| 812 | |
| 813 | return 1; |
| 814 | } |
| 815 | EXPORT_SYMBOL_GPL(l2tp_udp_recv_core); |
| 816 | |
| 817 | /* UDP encapsulation receive handler. See net/ipv4/udp.c. |
| 818 | * Return codes: |
| 819 | * 0 : success. |
| 820 | * <0: error |
| 821 | * >0: skb should be passed up to userspace as UDP. |
| 822 | */ |
| 823 | int l2tp_udp_encap_recv(struct sock *sk, struct sk_buff *skb) |
| 824 | { |
| 825 | struct l2tp_tunnel *tunnel; |
| 826 | |
| 827 | tunnel = l2tp_sock_to_tunnel(sk); |
| 828 | if (tunnel == NULL) |
| 829 | goto pass_up; |
| 830 | |
| 831 | PRINTK(tunnel->debug, L2TP_MSG_DATA, KERN_DEBUG, |
| 832 | "%s: received %d bytes\n", tunnel->name, skb->len); |
| 833 | |
| 834 | if (l2tp_udp_recv_core(tunnel, skb, tunnel->recv_payload_hook)) |
| 835 | goto pass_up_put; |
| 836 | |
| 837 | sock_put(sk); |
| 838 | return 0; |
| 839 | |
| 840 | pass_up_put: |
| 841 | sock_put(sk); |
| 842 | pass_up: |
| 843 | return 1; |
| 844 | } |
| 845 | EXPORT_SYMBOL_GPL(l2tp_udp_encap_recv); |
| 846 | |
| 847 | /************************************************************************ |
| 848 | * Transmit handling |
| 849 | ***********************************************************************/ |
| 850 | |
| 851 | /* Build an L2TP header for the session into the buffer provided. |
| 852 | */ |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 853 | static int l2tp_build_l2tpv2_header(struct l2tp_session *session, void *buf) |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 854 | { |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 855 | struct l2tp_tunnel *tunnel = session->tunnel; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 856 | __be16 *bufp = buf; |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 857 | __be16 *optr = buf; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 858 | u16 flags = L2TP_HDR_VER_2; |
| 859 | u32 tunnel_id = tunnel->peer_tunnel_id; |
| 860 | u32 session_id = session->peer_session_id; |
| 861 | |
| 862 | if (session->send_seq) |
| 863 | flags |= L2TP_HDRFLAG_S; |
| 864 | |
| 865 | /* Setup L2TP header. */ |
| 866 | *bufp++ = htons(flags); |
| 867 | *bufp++ = htons(tunnel_id); |
| 868 | *bufp++ = htons(session_id); |
| 869 | if (session->send_seq) { |
| 870 | *bufp++ = htons(session->ns); |
| 871 | *bufp++ = 0; |
| 872 | session->ns++; |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 873 | session->ns &= 0xffff; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 874 | PRINTK(session->debug, L2TP_MSG_SEQ, KERN_DEBUG, |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 875 | "%s: updated ns to %u\n", session->name, session->ns); |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 876 | } |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 877 | |
| 878 | return bufp - optr; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 879 | } |
| 880 | |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 881 | static int l2tp_build_l2tpv3_header(struct l2tp_session *session, void *buf) |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 882 | { |
James Chapman | 0d76751 | 2010-04-02 06:19:00 +0000 | [diff] [blame] | 883 | struct l2tp_tunnel *tunnel = session->tunnel; |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 884 | char *bufp = buf; |
| 885 | char *optr = bufp; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 886 | |
James Chapman | 0d76751 | 2010-04-02 06:19:00 +0000 | [diff] [blame] | 887 | /* Setup L2TP header. The header differs slightly for UDP and |
| 888 | * IP encapsulations. For UDP, there is 4 bytes of flags. |
| 889 | */ |
| 890 | if (tunnel->encap == L2TP_ENCAPTYPE_UDP) { |
| 891 | u16 flags = L2TP_HDR_VER_3; |
| 892 | *((__be16 *) bufp) = htons(flags); |
| 893 | bufp += 2; |
| 894 | *((__be16 *) bufp) = 0; |
| 895 | bufp += 2; |
| 896 | } |
| 897 | |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 898 | *((__be32 *) bufp) = htonl(session->peer_session_id); |
| 899 | bufp += 4; |
| 900 | if (session->cookie_len) { |
| 901 | memcpy(bufp, &session->cookie[0], session->cookie_len); |
| 902 | bufp += session->cookie_len; |
| 903 | } |
| 904 | if (session->l2specific_len) { |
| 905 | if (session->l2specific_type == L2TP_L2SPECTYPE_DEFAULT) { |
| 906 | u32 l2h = 0; |
| 907 | if (session->send_seq) { |
| 908 | l2h = 0x40000000 | session->ns; |
| 909 | session->ns++; |
| 910 | session->ns &= 0xffffff; |
| 911 | PRINTK(session->debug, L2TP_MSG_SEQ, KERN_DEBUG, |
| 912 | "%s: updated ns to %u\n", session->name, session->ns); |
| 913 | } |
| 914 | |
| 915 | *((__be32 *) bufp) = htonl(l2h); |
| 916 | } |
| 917 | bufp += session->l2specific_len; |
| 918 | } |
| 919 | if (session->offset) |
| 920 | bufp += session->offset; |
| 921 | |
| 922 | return bufp - optr; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 923 | } |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 924 | |
| 925 | int l2tp_xmit_core(struct l2tp_session *session, struct sk_buff *skb, size_t data_len) |
| 926 | { |
| 927 | struct l2tp_tunnel *tunnel = session->tunnel; |
| 928 | unsigned int len = skb->len; |
| 929 | int error; |
| 930 | |
| 931 | /* Debug */ |
| 932 | if (session->send_seq) |
| 933 | PRINTK(session->debug, L2TP_MSG_DATA, KERN_DEBUG, |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 934 | "%s: send %Zd bytes, ns=%u\n", session->name, |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 935 | data_len, session->ns - 1); |
| 936 | else |
| 937 | PRINTK(session->debug, L2TP_MSG_DATA, KERN_DEBUG, |
| 938 | "%s: send %Zd bytes\n", session->name, data_len); |
| 939 | |
| 940 | if (session->debug & L2TP_MSG_DATA) { |
| 941 | int i; |
James Chapman | 0d76751 | 2010-04-02 06:19:00 +0000 | [diff] [blame] | 942 | int uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0; |
| 943 | unsigned char *datap = skb->data + uhlen; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 944 | |
| 945 | printk(KERN_DEBUG "%s: xmit:", session->name); |
James Chapman | 0d76751 | 2010-04-02 06:19:00 +0000 | [diff] [blame] | 946 | for (i = 0; i < (len - uhlen); i++) { |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 947 | printk(" %02X", *datap++); |
| 948 | if (i == 31) { |
| 949 | printk(" ..."); |
| 950 | break; |
| 951 | } |
| 952 | } |
| 953 | printk("\n"); |
| 954 | } |
| 955 | |
| 956 | /* Queue the packet to IP for output */ |
Shan Wei | 4e15ed4 | 2010-04-15 16:43:08 +0000 | [diff] [blame] | 957 | skb->local_df = 1; |
| 958 | error = ip_queue_xmit(skb); |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 959 | |
| 960 | /* Update stats */ |
| 961 | if (error >= 0) { |
| 962 | tunnel->stats.tx_packets++; |
| 963 | tunnel->stats.tx_bytes += len; |
| 964 | session->stats.tx_packets++; |
| 965 | session->stats.tx_bytes += len; |
| 966 | } else { |
| 967 | tunnel->stats.tx_errors++; |
| 968 | session->stats.tx_errors++; |
| 969 | } |
| 970 | |
| 971 | return 0; |
| 972 | } |
| 973 | EXPORT_SYMBOL_GPL(l2tp_xmit_core); |
| 974 | |
| 975 | /* Automatically called when the skb is freed. |
| 976 | */ |
| 977 | static void l2tp_sock_wfree(struct sk_buff *skb) |
| 978 | { |
| 979 | sock_put(skb->sk); |
| 980 | } |
| 981 | |
| 982 | /* For data skbs that we transmit, we associate with the tunnel socket |
| 983 | * but don't do accounting. |
| 984 | */ |
| 985 | static inline void l2tp_skb_set_owner_w(struct sk_buff *skb, struct sock *sk) |
| 986 | { |
| 987 | sock_hold(sk); |
| 988 | skb->sk = sk; |
| 989 | skb->destructor = l2tp_sock_wfree; |
| 990 | } |
| 991 | |
| 992 | /* If caller requires the skb to have a ppp header, the header must be |
| 993 | * inserted in the skb data before calling this function. |
| 994 | */ |
| 995 | int l2tp_xmit_skb(struct l2tp_session *session, struct sk_buff *skb, int hdr_len) |
| 996 | { |
| 997 | int data_len = skb->len; |
James Chapman | 0d76751 | 2010-04-02 06:19:00 +0000 | [diff] [blame] | 998 | struct l2tp_tunnel *tunnel = session->tunnel; |
| 999 | struct sock *sk = tunnel->sock; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1000 | struct udphdr *uh; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1001 | struct inet_sock *inet; |
| 1002 | __wsum csum; |
| 1003 | int old_headroom; |
| 1004 | int new_headroom; |
| 1005 | int headroom; |
James Chapman | 0d76751 | 2010-04-02 06:19:00 +0000 | [diff] [blame] | 1006 | int uhlen = (tunnel->encap == L2TP_ENCAPTYPE_UDP) ? sizeof(struct udphdr) : 0; |
| 1007 | int udp_len; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1008 | |
| 1009 | /* Check that there's enough headroom in the skb to insert IP, |
| 1010 | * UDP and L2TP headers. If not enough, expand it to |
| 1011 | * make room. Adjust truesize. |
| 1012 | */ |
| 1013 | headroom = NET_SKB_PAD + sizeof(struct iphdr) + |
James Chapman | 0d76751 | 2010-04-02 06:19:00 +0000 | [diff] [blame] | 1014 | uhlen + hdr_len; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1015 | old_headroom = skb_headroom(skb); |
| 1016 | if (skb_cow_head(skb, headroom)) |
| 1017 | goto abort; |
| 1018 | |
| 1019 | new_headroom = skb_headroom(skb); |
| 1020 | skb_orphan(skb); |
| 1021 | skb->truesize += new_headroom - old_headroom; |
| 1022 | |
| 1023 | /* Setup L2TP header */ |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 1024 | session->build_header(session, __skb_push(skb, hdr_len)); |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1025 | |
James Chapman | 0d76751 | 2010-04-02 06:19:00 +0000 | [diff] [blame] | 1026 | /* Reset skb netfilter state */ |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1027 | memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); |
| 1028 | IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED | |
| 1029 | IPSKB_REROUTED); |
| 1030 | nf_reset(skb); |
| 1031 | |
| 1032 | /* Get routing info from the tunnel socket */ |
| 1033 | skb_dst_drop(skb); |
| 1034 | skb_dst_set(skb, dst_clone(__sk_dst_get(sk))); |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1035 | |
James Chapman | 0d76751 | 2010-04-02 06:19:00 +0000 | [diff] [blame] | 1036 | switch (tunnel->encap) { |
| 1037 | case L2TP_ENCAPTYPE_UDP: |
| 1038 | /* Setup UDP header */ |
| 1039 | inet = inet_sk(sk); |
| 1040 | __skb_push(skb, sizeof(*uh)); |
| 1041 | skb_reset_transport_header(skb); |
| 1042 | uh = udp_hdr(skb); |
| 1043 | uh->source = inet->inet_sport; |
| 1044 | uh->dest = inet->inet_dport; |
| 1045 | udp_len = uhlen + hdr_len + data_len; |
| 1046 | uh->len = htons(udp_len); |
| 1047 | uh->check = 0; |
| 1048 | |
| 1049 | /* Calculate UDP checksum if configured to do so */ |
| 1050 | if (sk->sk_no_check == UDP_CSUM_NOXMIT) |
| 1051 | skb->ip_summed = CHECKSUM_NONE; |
| 1052 | else if ((skb_dst(skb) && skb_dst(skb)->dev) && |
| 1053 | (!(skb_dst(skb)->dev->features & NETIF_F_V4_CSUM))) { |
| 1054 | skb->ip_summed = CHECKSUM_COMPLETE; |
| 1055 | csum = skb_checksum(skb, 0, udp_len, 0); |
| 1056 | uh->check = csum_tcpudp_magic(inet->inet_saddr, |
| 1057 | inet->inet_daddr, |
| 1058 | udp_len, IPPROTO_UDP, csum); |
| 1059 | if (uh->check == 0) |
| 1060 | uh->check = CSUM_MANGLED_0; |
| 1061 | } else { |
| 1062 | skb->ip_summed = CHECKSUM_PARTIAL; |
| 1063 | skb->csum_start = skb_transport_header(skb) - skb->head; |
| 1064 | skb->csum_offset = offsetof(struct udphdr, check); |
| 1065 | uh->check = ~csum_tcpudp_magic(inet->inet_saddr, |
| 1066 | inet->inet_daddr, |
| 1067 | udp_len, IPPROTO_UDP, 0); |
| 1068 | } |
| 1069 | break; |
| 1070 | |
| 1071 | case L2TP_ENCAPTYPE_IP: |
| 1072 | break; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1073 | } |
| 1074 | |
James Chapman | 0d76751 | 2010-04-02 06:19:00 +0000 | [diff] [blame] | 1075 | l2tp_skb_set_owner_w(skb, sk); |
| 1076 | |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1077 | l2tp_xmit_core(session, skb, data_len); |
| 1078 | |
| 1079 | abort: |
| 1080 | return 0; |
| 1081 | } |
| 1082 | EXPORT_SYMBOL_GPL(l2tp_xmit_skb); |
| 1083 | |
| 1084 | /***************************************************************************** |
| 1085 | * Tinnel and session create/destroy. |
| 1086 | *****************************************************************************/ |
| 1087 | |
| 1088 | /* Tunnel socket destruct hook. |
| 1089 | * The tunnel context is deleted only when all session sockets have been |
| 1090 | * closed. |
| 1091 | */ |
| 1092 | void l2tp_tunnel_destruct(struct sock *sk) |
| 1093 | { |
| 1094 | struct l2tp_tunnel *tunnel; |
| 1095 | |
| 1096 | tunnel = sk->sk_user_data; |
| 1097 | if (tunnel == NULL) |
| 1098 | goto end; |
| 1099 | |
| 1100 | PRINTK(tunnel->debug, L2TP_MSG_CONTROL, KERN_INFO, |
| 1101 | "%s: closing...\n", tunnel->name); |
| 1102 | |
| 1103 | /* Close all sessions */ |
| 1104 | l2tp_tunnel_closeall(tunnel); |
| 1105 | |
James Chapman | 0d76751 | 2010-04-02 06:19:00 +0000 | [diff] [blame] | 1106 | switch (tunnel->encap) { |
| 1107 | case L2TP_ENCAPTYPE_UDP: |
| 1108 | /* No longer an encapsulation socket. See net/ipv4/udp.c */ |
| 1109 | (udp_sk(sk))->encap_type = 0; |
| 1110 | (udp_sk(sk))->encap_rcv = NULL; |
| 1111 | break; |
| 1112 | case L2TP_ENCAPTYPE_IP: |
| 1113 | break; |
| 1114 | } |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1115 | |
| 1116 | /* Remove hooks into tunnel socket */ |
| 1117 | tunnel->sock = NULL; |
| 1118 | sk->sk_destruct = tunnel->old_sk_destruct; |
| 1119 | sk->sk_user_data = NULL; |
| 1120 | |
| 1121 | /* Call the original destructor */ |
| 1122 | if (sk->sk_destruct) |
| 1123 | (*sk->sk_destruct)(sk); |
| 1124 | |
| 1125 | /* We're finished with the socket */ |
| 1126 | l2tp_tunnel_dec_refcount(tunnel); |
| 1127 | |
| 1128 | end: |
| 1129 | return; |
| 1130 | } |
| 1131 | EXPORT_SYMBOL(l2tp_tunnel_destruct); |
| 1132 | |
| 1133 | /* When the tunnel is closed, all the attached sessions need to go too. |
| 1134 | */ |
| 1135 | void l2tp_tunnel_closeall(struct l2tp_tunnel *tunnel) |
| 1136 | { |
| 1137 | int hash; |
| 1138 | struct hlist_node *walk; |
| 1139 | struct hlist_node *tmp; |
| 1140 | struct l2tp_session *session; |
| 1141 | |
| 1142 | BUG_ON(tunnel == NULL); |
| 1143 | |
| 1144 | PRINTK(tunnel->debug, L2TP_MSG_CONTROL, KERN_INFO, |
| 1145 | "%s: closing all sessions...\n", tunnel->name); |
| 1146 | |
| 1147 | write_lock_bh(&tunnel->hlist_lock); |
| 1148 | for (hash = 0; hash < L2TP_HASH_SIZE; hash++) { |
| 1149 | again: |
| 1150 | hlist_for_each_safe(walk, tmp, &tunnel->session_hlist[hash]) { |
| 1151 | session = hlist_entry(walk, struct l2tp_session, hlist); |
| 1152 | |
| 1153 | PRINTK(session->debug, L2TP_MSG_CONTROL, KERN_INFO, |
| 1154 | "%s: closing session\n", session->name); |
| 1155 | |
| 1156 | hlist_del_init(&session->hlist); |
| 1157 | |
| 1158 | /* Since we should hold the sock lock while |
| 1159 | * doing any unbinding, we need to release the |
| 1160 | * lock we're holding before taking that lock. |
| 1161 | * Hold a reference to the sock so it doesn't |
| 1162 | * disappear as we're jumping between locks. |
| 1163 | */ |
| 1164 | if (session->ref != NULL) |
| 1165 | (*session->ref)(session); |
| 1166 | |
| 1167 | write_unlock_bh(&tunnel->hlist_lock); |
| 1168 | |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 1169 | if (tunnel->version != L2TP_HDR_VER_2) { |
| 1170 | struct l2tp_net *pn = l2tp_pernet(tunnel->l2tp_net); |
| 1171 | |
James Chapman | e02d494 | 2010-04-02 06:19:16 +0000 | [diff] [blame] | 1172 | spin_lock_bh(&pn->l2tp_session_hlist_lock); |
| 1173 | hlist_del_init_rcu(&session->global_hlist); |
| 1174 | spin_unlock_bh(&pn->l2tp_session_hlist_lock); |
| 1175 | synchronize_rcu(); |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 1176 | } |
| 1177 | |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1178 | if (session->session_close != NULL) |
| 1179 | (*session->session_close)(session); |
| 1180 | |
| 1181 | if (session->deref != NULL) |
| 1182 | (*session->deref)(session); |
| 1183 | |
| 1184 | write_lock_bh(&tunnel->hlist_lock); |
| 1185 | |
| 1186 | /* Now restart from the beginning of this hash |
| 1187 | * chain. We always remove a session from the |
| 1188 | * list so we are guaranteed to make forward |
| 1189 | * progress. |
| 1190 | */ |
| 1191 | goto again; |
| 1192 | } |
| 1193 | } |
| 1194 | write_unlock_bh(&tunnel->hlist_lock); |
| 1195 | } |
| 1196 | EXPORT_SYMBOL_GPL(l2tp_tunnel_closeall); |
| 1197 | |
| 1198 | /* Really kill the tunnel. |
| 1199 | * Come here only when all sessions have been cleared from the tunnel. |
| 1200 | */ |
| 1201 | void l2tp_tunnel_free(struct l2tp_tunnel *tunnel) |
| 1202 | { |
| 1203 | struct l2tp_net *pn = l2tp_pernet(tunnel->l2tp_net); |
| 1204 | |
| 1205 | BUG_ON(atomic_read(&tunnel->ref_count) != 0); |
| 1206 | BUG_ON(tunnel->sock != NULL); |
| 1207 | |
| 1208 | PRINTK(tunnel->debug, L2TP_MSG_CONTROL, KERN_INFO, |
| 1209 | "%s: free...\n", tunnel->name); |
| 1210 | |
| 1211 | /* Remove from tunnel list */ |
James Chapman | e02d494 | 2010-04-02 06:19:16 +0000 | [diff] [blame] | 1212 | spin_lock_bh(&pn->l2tp_tunnel_list_lock); |
| 1213 | list_del_rcu(&tunnel->list); |
| 1214 | spin_unlock_bh(&pn->l2tp_tunnel_list_lock); |
| 1215 | synchronize_rcu(); |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1216 | |
| 1217 | atomic_dec(&l2tp_tunnel_count); |
| 1218 | kfree(tunnel); |
| 1219 | } |
| 1220 | EXPORT_SYMBOL_GPL(l2tp_tunnel_free); |
| 1221 | |
James Chapman | 789a4a2 | 2010-04-02 06:19:40 +0000 | [diff] [blame] | 1222 | /* Create a socket for the tunnel, if one isn't set up by |
| 1223 | * userspace. This is used for static tunnels where there is no |
| 1224 | * managing L2TP daemon. |
| 1225 | */ |
| 1226 | static int l2tp_tunnel_sock_create(u32 tunnel_id, u32 peer_tunnel_id, struct l2tp_tunnel_cfg *cfg, struct socket **sockp) |
| 1227 | { |
| 1228 | int err = -EINVAL; |
| 1229 | struct sockaddr_in udp_addr; |
| 1230 | struct sockaddr_l2tpip ip_addr; |
Eric Dumazet | 7bddd0d | 2010-04-04 01:02:46 -0700 | [diff] [blame] | 1231 | struct socket *sock = NULL; |
James Chapman | 789a4a2 | 2010-04-02 06:19:40 +0000 | [diff] [blame] | 1232 | |
| 1233 | switch (cfg->encap) { |
| 1234 | case L2TP_ENCAPTYPE_UDP: |
| 1235 | err = sock_create(AF_INET, SOCK_DGRAM, 0, sockp); |
| 1236 | if (err < 0) |
| 1237 | goto out; |
| 1238 | |
| 1239 | sock = *sockp; |
| 1240 | |
| 1241 | memset(&udp_addr, 0, sizeof(udp_addr)); |
| 1242 | udp_addr.sin_family = AF_INET; |
| 1243 | udp_addr.sin_addr = cfg->local_ip; |
| 1244 | udp_addr.sin_port = htons(cfg->local_udp_port); |
| 1245 | err = kernel_bind(sock, (struct sockaddr *) &udp_addr, sizeof(udp_addr)); |
| 1246 | if (err < 0) |
| 1247 | goto out; |
| 1248 | |
| 1249 | udp_addr.sin_family = AF_INET; |
| 1250 | udp_addr.sin_addr = cfg->peer_ip; |
| 1251 | udp_addr.sin_port = htons(cfg->peer_udp_port); |
| 1252 | err = kernel_connect(sock, (struct sockaddr *) &udp_addr, sizeof(udp_addr), 0); |
| 1253 | if (err < 0) |
| 1254 | goto out; |
| 1255 | |
| 1256 | if (!cfg->use_udp_checksums) |
| 1257 | sock->sk->sk_no_check = UDP_CSUM_NOXMIT; |
| 1258 | |
| 1259 | break; |
| 1260 | |
| 1261 | case L2TP_ENCAPTYPE_IP: |
| 1262 | err = sock_create(AF_INET, SOCK_DGRAM, IPPROTO_L2TP, sockp); |
| 1263 | if (err < 0) |
| 1264 | goto out; |
| 1265 | |
| 1266 | sock = *sockp; |
| 1267 | |
| 1268 | memset(&ip_addr, 0, sizeof(ip_addr)); |
| 1269 | ip_addr.l2tp_family = AF_INET; |
| 1270 | ip_addr.l2tp_addr = cfg->local_ip; |
| 1271 | ip_addr.l2tp_conn_id = tunnel_id; |
| 1272 | err = kernel_bind(sock, (struct sockaddr *) &ip_addr, sizeof(ip_addr)); |
| 1273 | if (err < 0) |
| 1274 | goto out; |
| 1275 | |
| 1276 | ip_addr.l2tp_family = AF_INET; |
| 1277 | ip_addr.l2tp_addr = cfg->peer_ip; |
| 1278 | ip_addr.l2tp_conn_id = peer_tunnel_id; |
| 1279 | err = kernel_connect(sock, (struct sockaddr *) &ip_addr, sizeof(ip_addr), 0); |
| 1280 | if (err < 0) |
| 1281 | goto out; |
| 1282 | |
| 1283 | break; |
| 1284 | |
| 1285 | default: |
| 1286 | goto out; |
| 1287 | } |
| 1288 | |
| 1289 | out: |
| 1290 | if ((err < 0) && sock) { |
| 1291 | sock_release(sock); |
| 1292 | *sockp = NULL; |
| 1293 | } |
| 1294 | |
| 1295 | return err; |
| 1296 | } |
| 1297 | |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1298 | int l2tp_tunnel_create(struct net *net, int fd, int version, u32 tunnel_id, u32 peer_tunnel_id, struct l2tp_tunnel_cfg *cfg, struct l2tp_tunnel **tunnelp) |
| 1299 | { |
| 1300 | struct l2tp_tunnel *tunnel = NULL; |
| 1301 | int err; |
| 1302 | struct socket *sock = NULL; |
| 1303 | struct sock *sk = NULL; |
| 1304 | struct l2tp_net *pn; |
James Chapman | 0d76751 | 2010-04-02 06:19:00 +0000 | [diff] [blame] | 1305 | enum l2tp_encap_type encap = L2TP_ENCAPTYPE_UDP; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1306 | |
| 1307 | /* Get the tunnel socket from the fd, which was opened by |
James Chapman | 789a4a2 | 2010-04-02 06:19:40 +0000 | [diff] [blame] | 1308 | * the userspace L2TP daemon. If not specified, create a |
| 1309 | * kernel socket. |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1310 | */ |
James Chapman | 789a4a2 | 2010-04-02 06:19:40 +0000 | [diff] [blame] | 1311 | if (fd < 0) { |
| 1312 | err = l2tp_tunnel_sock_create(tunnel_id, peer_tunnel_id, cfg, &sock); |
| 1313 | if (err < 0) |
| 1314 | goto err; |
| 1315 | } else { |
| 1316 | err = -EBADF; |
| 1317 | sock = sockfd_lookup(fd, &err); |
| 1318 | if (!sock) { |
| 1319 | printk(KERN_ERR "tunl %hu: sockfd_lookup(fd=%d) returned %d\n", |
| 1320 | tunnel_id, fd, err); |
| 1321 | goto err; |
| 1322 | } |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1323 | } |
| 1324 | |
| 1325 | sk = sock->sk; |
| 1326 | |
James Chapman | 0d76751 | 2010-04-02 06:19:00 +0000 | [diff] [blame] | 1327 | if (cfg != NULL) |
| 1328 | encap = cfg->encap; |
| 1329 | |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1330 | /* Quick sanity checks */ |
James Chapman | 0d76751 | 2010-04-02 06:19:00 +0000 | [diff] [blame] | 1331 | switch (encap) { |
| 1332 | case L2TP_ENCAPTYPE_UDP: |
| 1333 | err = -EPROTONOSUPPORT; |
| 1334 | if (sk->sk_protocol != IPPROTO_UDP) { |
| 1335 | printk(KERN_ERR "tunl %hu: fd %d wrong protocol, got %d, expected %d\n", |
| 1336 | tunnel_id, fd, sk->sk_protocol, IPPROTO_UDP); |
| 1337 | goto err; |
| 1338 | } |
| 1339 | break; |
| 1340 | case L2TP_ENCAPTYPE_IP: |
| 1341 | err = -EPROTONOSUPPORT; |
| 1342 | if (sk->sk_protocol != IPPROTO_L2TP) { |
| 1343 | printk(KERN_ERR "tunl %hu: fd %d wrong protocol, got %d, expected %d\n", |
| 1344 | tunnel_id, fd, sk->sk_protocol, IPPROTO_L2TP); |
| 1345 | goto err; |
| 1346 | } |
| 1347 | break; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1348 | } |
| 1349 | |
| 1350 | /* Check if this socket has already been prepped */ |
| 1351 | tunnel = (struct l2tp_tunnel *)sk->sk_user_data; |
| 1352 | if (tunnel != NULL) { |
| 1353 | /* This socket has already been prepped */ |
| 1354 | err = -EBUSY; |
| 1355 | goto err; |
| 1356 | } |
| 1357 | |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1358 | tunnel = kzalloc(sizeof(struct l2tp_tunnel), GFP_KERNEL); |
| 1359 | if (tunnel == NULL) { |
| 1360 | err = -ENOMEM; |
| 1361 | goto err; |
| 1362 | } |
| 1363 | |
| 1364 | tunnel->version = version; |
| 1365 | tunnel->tunnel_id = tunnel_id; |
| 1366 | tunnel->peer_tunnel_id = peer_tunnel_id; |
| 1367 | tunnel->debug = L2TP_DEFAULT_DEBUG_FLAGS; |
| 1368 | |
| 1369 | tunnel->magic = L2TP_TUNNEL_MAGIC; |
| 1370 | sprintf(&tunnel->name[0], "tunl %u", tunnel_id); |
| 1371 | rwlock_init(&tunnel->hlist_lock); |
| 1372 | |
| 1373 | /* The net we belong to */ |
| 1374 | tunnel->l2tp_net = net; |
| 1375 | pn = l2tp_pernet(net); |
| 1376 | |
James Chapman | 0d76751 | 2010-04-02 06:19:00 +0000 | [diff] [blame] | 1377 | if (cfg != NULL) |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1378 | tunnel->debug = cfg->debug; |
| 1379 | |
| 1380 | /* Mark socket as an encapsulation socket. See net/ipv4/udp.c */ |
James Chapman | 0d76751 | 2010-04-02 06:19:00 +0000 | [diff] [blame] | 1381 | tunnel->encap = encap; |
| 1382 | if (encap == L2TP_ENCAPTYPE_UDP) { |
| 1383 | /* Mark socket as an encapsulation socket. See net/ipv4/udp.c */ |
| 1384 | udp_sk(sk)->encap_type = UDP_ENCAP_L2TPINUDP; |
| 1385 | udp_sk(sk)->encap_rcv = l2tp_udp_encap_recv; |
| 1386 | } |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1387 | |
| 1388 | sk->sk_user_data = tunnel; |
| 1389 | |
| 1390 | /* Hook on the tunnel socket destructor so that we can cleanup |
| 1391 | * if the tunnel socket goes away. |
| 1392 | */ |
| 1393 | tunnel->old_sk_destruct = sk->sk_destruct; |
| 1394 | sk->sk_destruct = &l2tp_tunnel_destruct; |
| 1395 | tunnel->sock = sk; |
| 1396 | sk->sk_allocation = GFP_ATOMIC; |
| 1397 | |
| 1398 | /* Add tunnel to our list */ |
| 1399 | INIT_LIST_HEAD(&tunnel->list); |
James Chapman | e02d494 | 2010-04-02 06:19:16 +0000 | [diff] [blame] | 1400 | spin_lock_bh(&pn->l2tp_tunnel_list_lock); |
| 1401 | list_add_rcu(&tunnel->list, &pn->l2tp_tunnel_list); |
| 1402 | spin_unlock_bh(&pn->l2tp_tunnel_list_lock); |
| 1403 | synchronize_rcu(); |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1404 | atomic_inc(&l2tp_tunnel_count); |
| 1405 | |
| 1406 | /* Bump the reference count. The tunnel context is deleted |
| 1407 | * only when this drops to zero. |
| 1408 | */ |
| 1409 | l2tp_tunnel_inc_refcount(tunnel); |
| 1410 | |
| 1411 | err = 0; |
| 1412 | err: |
| 1413 | if (tunnelp) |
| 1414 | *tunnelp = tunnel; |
| 1415 | |
James Chapman | 789a4a2 | 2010-04-02 06:19:40 +0000 | [diff] [blame] | 1416 | /* If tunnel's socket was created by the kernel, it doesn't |
| 1417 | * have a file. |
| 1418 | */ |
| 1419 | if (sock && sock->file) |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1420 | sockfd_put(sock); |
| 1421 | |
| 1422 | return err; |
| 1423 | } |
| 1424 | EXPORT_SYMBOL_GPL(l2tp_tunnel_create); |
| 1425 | |
James Chapman | 309795f | 2010-04-02 06:19:10 +0000 | [diff] [blame] | 1426 | /* This function is used by the netlink TUNNEL_DELETE command. |
| 1427 | */ |
| 1428 | int l2tp_tunnel_delete(struct l2tp_tunnel *tunnel) |
| 1429 | { |
| 1430 | int err = 0; |
James Chapman | 789a4a2 | 2010-04-02 06:19:40 +0000 | [diff] [blame] | 1431 | struct socket *sock = tunnel->sock ? tunnel->sock->sk_socket : NULL; |
James Chapman | 309795f | 2010-04-02 06:19:10 +0000 | [diff] [blame] | 1432 | |
| 1433 | /* Force the tunnel socket to close. This will eventually |
| 1434 | * cause the tunnel to be deleted via the normal socket close |
| 1435 | * mechanisms when userspace closes the tunnel socket. |
| 1436 | */ |
James Chapman | 789a4a2 | 2010-04-02 06:19:40 +0000 | [diff] [blame] | 1437 | if (sock != NULL) { |
| 1438 | err = inet_shutdown(sock, 2); |
| 1439 | |
| 1440 | /* If the tunnel's socket was created by the kernel, |
| 1441 | * close the socket here since the socket was not |
| 1442 | * created by userspace. |
| 1443 | */ |
| 1444 | if (sock->file == NULL) |
| 1445 | err = inet_release(sock); |
| 1446 | } |
James Chapman | 309795f | 2010-04-02 06:19:10 +0000 | [diff] [blame] | 1447 | |
| 1448 | return err; |
| 1449 | } |
| 1450 | EXPORT_SYMBOL_GPL(l2tp_tunnel_delete); |
| 1451 | |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1452 | /* Really kill the session. |
| 1453 | */ |
| 1454 | void l2tp_session_free(struct l2tp_session *session) |
| 1455 | { |
| 1456 | struct l2tp_tunnel *tunnel; |
| 1457 | |
| 1458 | BUG_ON(atomic_read(&session->ref_count) != 0); |
| 1459 | |
| 1460 | tunnel = session->tunnel; |
| 1461 | if (tunnel != NULL) { |
| 1462 | BUG_ON(tunnel->magic != L2TP_TUNNEL_MAGIC); |
| 1463 | |
| 1464 | /* Delete the session from the hash */ |
| 1465 | write_lock_bh(&tunnel->hlist_lock); |
| 1466 | hlist_del_init(&session->hlist); |
| 1467 | write_unlock_bh(&tunnel->hlist_lock); |
| 1468 | |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 1469 | /* Unlink from the global hash if not L2TPv2 */ |
| 1470 | if (tunnel->version != L2TP_HDR_VER_2) { |
| 1471 | struct l2tp_net *pn = l2tp_pernet(tunnel->l2tp_net); |
| 1472 | |
James Chapman | e02d494 | 2010-04-02 06:19:16 +0000 | [diff] [blame] | 1473 | spin_lock_bh(&pn->l2tp_session_hlist_lock); |
| 1474 | hlist_del_init_rcu(&session->global_hlist); |
| 1475 | spin_unlock_bh(&pn->l2tp_session_hlist_lock); |
| 1476 | synchronize_rcu(); |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 1477 | } |
| 1478 | |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1479 | if (session->session_id != 0) |
| 1480 | atomic_dec(&l2tp_session_count); |
| 1481 | |
| 1482 | sock_put(tunnel->sock); |
| 1483 | |
| 1484 | /* This will delete the tunnel context if this |
| 1485 | * is the last session on the tunnel. |
| 1486 | */ |
| 1487 | session->tunnel = NULL; |
| 1488 | l2tp_tunnel_dec_refcount(tunnel); |
| 1489 | } |
| 1490 | |
| 1491 | kfree(session); |
| 1492 | |
| 1493 | return; |
| 1494 | } |
| 1495 | EXPORT_SYMBOL_GPL(l2tp_session_free); |
| 1496 | |
James Chapman | 309795f | 2010-04-02 06:19:10 +0000 | [diff] [blame] | 1497 | /* This function is used by the netlink SESSION_DELETE command and by |
| 1498 | pseudowire modules. |
| 1499 | */ |
| 1500 | int l2tp_session_delete(struct l2tp_session *session) |
| 1501 | { |
| 1502 | if (session->session_close != NULL) |
| 1503 | (*session->session_close)(session); |
| 1504 | |
| 1505 | l2tp_session_dec_refcount(session); |
| 1506 | |
| 1507 | return 0; |
| 1508 | } |
| 1509 | EXPORT_SYMBOL_GPL(l2tp_session_delete); |
| 1510 | |
| 1511 | |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 1512 | /* We come here whenever a session's send_seq, cookie_len or |
| 1513 | * l2specific_len parameters are set. |
| 1514 | */ |
| 1515 | void l2tp_session_set_header_len(struct l2tp_session *session, int version) |
| 1516 | { |
| 1517 | if (version == L2TP_HDR_VER_2) { |
| 1518 | session->hdr_len = 6; |
| 1519 | if (session->send_seq) |
| 1520 | session->hdr_len += 4; |
| 1521 | } else { |
James Chapman | 0d76751 | 2010-04-02 06:19:00 +0000 | [diff] [blame] | 1522 | session->hdr_len = 4 + session->cookie_len + session->l2specific_len + session->offset; |
| 1523 | if (session->tunnel->encap == L2TP_ENCAPTYPE_UDP) |
| 1524 | session->hdr_len += 4; |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 1525 | } |
| 1526 | |
| 1527 | } |
| 1528 | EXPORT_SYMBOL_GPL(l2tp_session_set_header_len); |
| 1529 | |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1530 | struct l2tp_session *l2tp_session_create(int priv_size, struct l2tp_tunnel *tunnel, u32 session_id, u32 peer_session_id, struct l2tp_session_cfg *cfg) |
| 1531 | { |
| 1532 | struct l2tp_session *session; |
| 1533 | |
| 1534 | session = kzalloc(sizeof(struct l2tp_session) + priv_size, GFP_KERNEL); |
| 1535 | if (session != NULL) { |
| 1536 | session->magic = L2TP_SESSION_MAGIC; |
| 1537 | session->tunnel = tunnel; |
| 1538 | |
| 1539 | session->session_id = session_id; |
| 1540 | session->peer_session_id = peer_session_id; |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 1541 | session->nr = 1; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1542 | |
| 1543 | sprintf(&session->name[0], "sess %u/%u", |
| 1544 | tunnel->tunnel_id, session->session_id); |
| 1545 | |
| 1546 | skb_queue_head_init(&session->reorder_q); |
| 1547 | |
| 1548 | INIT_HLIST_NODE(&session->hlist); |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 1549 | INIT_HLIST_NODE(&session->global_hlist); |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1550 | |
| 1551 | /* Inherit debug options from tunnel */ |
| 1552 | session->debug = tunnel->debug; |
| 1553 | |
| 1554 | if (cfg) { |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 1555 | session->pwtype = cfg->pw_type; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1556 | session->debug = cfg->debug; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1557 | session->mtu = cfg->mtu; |
| 1558 | session->mru = cfg->mru; |
| 1559 | session->send_seq = cfg->send_seq; |
| 1560 | session->recv_seq = cfg->recv_seq; |
| 1561 | session->lns_mode = cfg->lns_mode; |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 1562 | session->reorder_timeout = cfg->reorder_timeout; |
| 1563 | session->offset = cfg->offset; |
| 1564 | session->l2specific_type = cfg->l2specific_type; |
| 1565 | session->l2specific_len = cfg->l2specific_len; |
| 1566 | session->cookie_len = cfg->cookie_len; |
| 1567 | memcpy(&session->cookie[0], &cfg->cookie[0], cfg->cookie_len); |
| 1568 | session->peer_cookie_len = cfg->peer_cookie_len; |
| 1569 | memcpy(&session->peer_cookie[0], &cfg->peer_cookie[0], cfg->peer_cookie_len); |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1570 | } |
| 1571 | |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 1572 | if (tunnel->version == L2TP_HDR_VER_2) |
| 1573 | session->build_header = l2tp_build_l2tpv2_header; |
| 1574 | else |
| 1575 | session->build_header = l2tp_build_l2tpv3_header; |
| 1576 | |
| 1577 | l2tp_session_set_header_len(session, tunnel->version); |
| 1578 | |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1579 | /* Bump the reference count. The session context is deleted |
| 1580 | * only when this drops to zero. |
| 1581 | */ |
| 1582 | l2tp_session_inc_refcount(session); |
| 1583 | l2tp_tunnel_inc_refcount(tunnel); |
| 1584 | |
| 1585 | /* Ensure tunnel socket isn't deleted */ |
| 1586 | sock_hold(tunnel->sock); |
| 1587 | |
| 1588 | /* Add session to the tunnel's hash list */ |
| 1589 | write_lock_bh(&tunnel->hlist_lock); |
| 1590 | hlist_add_head(&session->hlist, |
| 1591 | l2tp_session_id_hash(tunnel, session_id)); |
| 1592 | write_unlock_bh(&tunnel->hlist_lock); |
| 1593 | |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 1594 | /* And to the global session list if L2TPv3 */ |
| 1595 | if (tunnel->version != L2TP_HDR_VER_2) { |
| 1596 | struct l2tp_net *pn = l2tp_pernet(tunnel->l2tp_net); |
| 1597 | |
James Chapman | e02d494 | 2010-04-02 06:19:16 +0000 | [diff] [blame] | 1598 | spin_lock_bh(&pn->l2tp_session_hlist_lock); |
| 1599 | hlist_add_head_rcu(&session->global_hlist, |
| 1600 | l2tp_session_id_hash_2(pn, session_id)); |
| 1601 | spin_unlock_bh(&pn->l2tp_session_hlist_lock); |
| 1602 | synchronize_rcu(); |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 1603 | } |
| 1604 | |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1605 | /* Ignore management session in session count value */ |
| 1606 | if (session->session_id != 0) |
| 1607 | atomic_inc(&l2tp_session_count); |
| 1608 | } |
| 1609 | |
| 1610 | return session; |
| 1611 | } |
| 1612 | EXPORT_SYMBOL_GPL(l2tp_session_create); |
| 1613 | |
| 1614 | /***************************************************************************** |
| 1615 | * Init and cleanup |
| 1616 | *****************************************************************************/ |
| 1617 | |
| 1618 | static __net_init int l2tp_init_net(struct net *net) |
| 1619 | { |
Jiri Pirko | e773aaf | 2010-04-23 00:53:39 +0000 | [diff] [blame] | 1620 | struct l2tp_net *pn = net_generic(net, l2tp_net_id); |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 1621 | int hash; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1622 | |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1623 | INIT_LIST_HEAD(&pn->l2tp_tunnel_list); |
James Chapman | e02d494 | 2010-04-02 06:19:16 +0000 | [diff] [blame] | 1624 | spin_lock_init(&pn->l2tp_tunnel_list_lock); |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1625 | |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 1626 | for (hash = 0; hash < L2TP_HASH_SIZE_2; hash++) |
| 1627 | INIT_HLIST_HEAD(&pn->l2tp_session_hlist[hash]); |
| 1628 | |
James Chapman | e02d494 | 2010-04-02 06:19:16 +0000 | [diff] [blame] | 1629 | spin_lock_init(&pn->l2tp_session_hlist_lock); |
James Chapman | f7faffa | 2010-04-02 06:18:49 +0000 | [diff] [blame] | 1630 | |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1631 | return 0; |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1632 | } |
| 1633 | |
| 1634 | static struct pernet_operations l2tp_net_ops = { |
| 1635 | .init = l2tp_init_net, |
James Chapman | fd558d1 | 2010-04-02 06:18:33 +0000 | [diff] [blame] | 1636 | .id = &l2tp_net_id, |
| 1637 | .size = sizeof(struct l2tp_net), |
| 1638 | }; |
| 1639 | |
| 1640 | static int __init l2tp_init(void) |
| 1641 | { |
| 1642 | int rc = 0; |
| 1643 | |
| 1644 | rc = register_pernet_device(&l2tp_net_ops); |
| 1645 | if (rc) |
| 1646 | goto out; |
| 1647 | |
| 1648 | printk(KERN_INFO "L2TP core driver, %s\n", L2TP_DRV_VERSION); |
| 1649 | |
| 1650 | out: |
| 1651 | return rc; |
| 1652 | } |
| 1653 | |
| 1654 | static void __exit l2tp_exit(void) |
| 1655 | { |
| 1656 | unregister_pernet_device(&l2tp_net_ops); |
| 1657 | } |
| 1658 | |
| 1659 | module_init(l2tp_init); |
| 1660 | module_exit(l2tp_exit); |
| 1661 | |
| 1662 | MODULE_AUTHOR("James Chapman <jchapman@katalix.com>"); |
| 1663 | MODULE_DESCRIPTION("L2TP core"); |
| 1664 | MODULE_LICENSE("GPL"); |
| 1665 | MODULE_VERSION(L2TP_DRV_VERSION); |
| 1666 | |