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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/** -*- linux-c -*- ***********************************************************
2 * Linux PPP over Ethernet (PPPoX/PPPoE) Sockets
3 *
4 * PPPoX --- Generic PPP encapsulation socket family
5 * PPPoE --- PPP over Ethernet (RFC 2516)
6 *
7 *
8 * Version: 0.7.0
9 *
Florian Zumbiehl90719db2007-03-02 13:16:56 -080010 * 070228 : Fix to allow multiple sessions with same remote MAC and same
11 * session id by including the local device ifindex in the
12 * tuple identifying a session. This also ensures packets can't
13 * be injected into a session from interfaces other than the one
14 * specified by userspace. Florian Zumbiehl <florz@florz.de>
15 * (Oh, BTW, this one is YYMMDD, in case you were wondering ...)
Linus Torvalds1da177e2005-04-16 15:20:36 -070016 * 220102 : Fix module use count on failure in pppoe_create, pppox_sk -acme
17 * 030700 : Fixed connect logic to allow for disconnect.
18 * 270700 : Fixed potential SMP problems; we must protect against
19 * simultaneous invocation of ppp_input
20 * and ppp_unregister_channel.
21 * 040800 : Respect reference count mechanisms on net-devices.
22 * 200800 : fix kfree(skb) in pppoe_rcv (acme)
23 * Module reference count is decremented in the right spot now,
24 * guards against sock_put not actually freeing the sk
25 * in pppoe_release.
26 * 051000 : Initialization cleanup.
27 * 111100 : Fix recvmsg.
28 * 050101 : Fix PADT procesing.
29 * 140501 : Use pppoe_rcv_core to handle all backlog. (Alexey)
30 * 170701 : Do not lock_sock with rwlock held. (DaveM)
31 * Ignore discovery frames if user has socket
32 * locked. (DaveM)
33 * Ignore return value of dev_queue_xmit in __pppoe_xmit
34 * or else we may kfree an SKB twice. (DaveM)
35 * 190701 : When doing copies of skb's in __pppoe_xmit, always delete
36 * the original skb that was passed in on success, never on
37 * failure. Delete the copy of the skb on failure to avoid
38 * a memory leak.
39 * 081001 : Misc. cleanup (licence string, non-blocking, prevent
40 * reference of device on close).
41 * 121301 : New ppp channels interface; cannot unregister a channel
42 * from interrupts. Thus, we mark the socket as a ZOMBIE
43 * and do the unregistration later.
44 * 081002 : seq_file support for proc stuff -acme
45 * 111602 : Merge all 2.4 fixes into 2.5/2.6 tree. Label 2.5/2.6
46 * as version 0.7. Spacing cleanup.
47 * Author: Michal Ostrowski <mostrows@speakeasy.net>
48 * Contributors:
49 * Arnaldo Carvalho de Melo <acme@conectiva.com.br>
50 * David S. Miller (davem@redhat.com)
51 *
52 * License:
53 * This program is free software; you can redistribute it and/or
54 * modify it under the terms of the GNU General Public License
55 * as published by the Free Software Foundation; either version
56 * 2 of the License, or (at your option) any later version.
57 *
58 */
59
60#include <linux/string.h>
61#include <linux/module.h>
62#include <linux/kernel.h>
63#include <linux/slab.h>
64#include <linux/errno.h>
65#include <linux/netdevice.h>
66#include <linux/net.h>
67#include <linux/inetdevice.h>
68#include <linux/etherdevice.h>
69#include <linux/skbuff.h>
70#include <linux/init.h>
71#include <linux/if_ether.h>
72#include <linux/if_pppox.h>
73#include <linux/ppp_channel.h>
74#include <linux/ppp_defs.h>
Paul Mackerras4b32da2b2012-03-04 12:56:55 +000075#include <linux/ppp-ioctl.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070076#include <linux/notifier.h>
77#include <linux/file.h>
78#include <linux/proc_fs.h>
79#include <linux/seq_file.h>
80
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -080081#include <linux/nsproxy.h>
Eric W. Biederman457c4cb2007-09-12 12:01:34 +020082#include <net/net_namespace.h>
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -080083#include <net/netns/generic.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070084#include <net/sock.h>
85
86#include <asm/uaccess.h>
87
88#define PPPOE_HASH_BITS 4
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -080089#define PPPOE_HASH_SIZE (1 << PPPOE_HASH_BITS)
90#define PPPOE_HASH_MASK (PPPOE_HASH_SIZE - 1)
Linus Torvalds1da177e2005-04-16 15:20:36 -070091
Linus Torvalds1da177e2005-04-16 15:20:36 -070092static int __pppoe_xmit(struct sock *sk, struct sk_buff *skb);
93
David S. Miller17ba15f2005-12-27 20:57:40 -080094static const struct proto_ops pppoe_ops;
stephen hemmingerd7100da2010-08-04 07:34:36 +000095static const struct ppp_channel_ops pppoe_chan_ops;
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -080096
97/* per-net private data for this module */
Eric Dumazetf99189b2009-11-17 10:42:49 +000098static int pppoe_net_id __read_mostly;
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -080099struct pppoe_net {
100 /*
101 * we could use _single_ hash table for all
102 * nets by injecting net id into the hash but
103 * it would increase hash chains and add
104 * a few additional math comparations messy
105 * as well, moreover in case of SMP less locking
106 * controversy here
107 */
108 struct pppox_sock *hash_table[PPPOE_HASH_SIZE];
109 rwlock_t hash_lock;
110};
111
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800112/*
113 * PPPoE could be in the following stages:
114 * 1) Discovery stage (to obtain remote MAC and Session ID)
115 * 2) Session stage (MAC and SID are known)
116 *
117 * Ethernet frames have a special tag for this but
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300118 * we use simpler approach based on session id
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800119 */
120static inline bool stage_session(__be16 sid)
121{
122 return sid != 0;
123}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800125static inline struct pppoe_net *pppoe_pernet(struct net *net)
126{
127 BUG_ON(!net);
128
129 return net_generic(net, pppoe_net_id);
130}
131
Linus Torvalds1da177e2005-04-16 15:20:36 -0700132static inline int cmp_2_addr(struct pppoe_addr *a, struct pppoe_addr *b)
133{
dingtianhong7ed8ca52013-12-26 19:40:35 +0800134 return a->sid == b->sid && ether_addr_equal(a->remote, b->remote);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135}
136
Al Virob963dc12007-08-23 02:55:33 -0400137static inline int cmp_addr(struct pppoe_addr *a, __be16 sid, char *addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700138{
dingtianhong7ed8ca52013-12-26 19:40:35 +0800139 return a->sid == sid && ether_addr_equal(a->remote, addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140}
141
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800142#if 8 % PPPOE_HASH_BITS
Florian Zumbiehlf1543f82007-07-31 13:47:57 -0700143#error 8 must be a multiple of PPPOE_HASH_BITS
144#endif
145
Al Virob963dc12007-08-23 02:55:33 -0400146static int hash_item(__be16 sid, unsigned char *addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700147{
Florian Zumbiehlf1543f82007-07-31 13:47:57 -0700148 unsigned char hash = 0;
149 unsigned int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700150
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800151 for (i = 0; i < ETH_ALEN; i++)
Florian Zumbiehlf1543f82007-07-31 13:47:57 -0700152 hash ^= addr[i];
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800153 for (i = 0; i < sizeof(sid_t) * 8; i += 8)
154 hash ^= (__force __u32)sid >> i;
155 for (i = 8; (i >>= 1) >= PPPOE_HASH_BITS;)
156 hash ^= hash >> i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800158 return hash & PPPOE_HASH_MASK;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700159}
160
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161/**********************************************************************
162 *
163 * Set/get/delete/rehash items (internal versions)
164 *
165 **********************************************************************/
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800166static struct pppox_sock *__get_item(struct pppoe_net *pn, __be16 sid,
167 unsigned char *addr, int ifindex)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700168{
169 int hash = hash_item(sid, addr);
170 struct pppox_sock *ret;
171
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800172 ret = pn->hash_table[hash];
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800173 while (ret) {
174 if (cmp_addr(&ret->pppoe_pa, sid, addr) &&
175 ret->pppoe_ifindex == ifindex)
176 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700177
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800178 ret = ret->next;
179 }
180
181 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182}
183
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800184static int __set_item(struct pppoe_net *pn, struct pppox_sock *po)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185{
186 int hash = hash_item(po->pppoe_pa.sid, po->pppoe_pa.remote);
187 struct pppox_sock *ret;
188
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800189 ret = pn->hash_table[hash];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700190 while (ret) {
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800191 if (cmp_2_addr(&ret->pppoe_pa, &po->pppoe_pa) &&
192 ret->pppoe_ifindex == po->pppoe_ifindex)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700193 return -EALREADY;
194
195 ret = ret->next;
196 }
197
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800198 po->next = pn->hash_table[hash];
199 pn->hash_table[hash] = po;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200
201 return 0;
202}
203
Rami Rosen3b12bb62012-05-17 05:04:50 +0000204static void __delete_item(struct pppoe_net *pn, __be16 sid,
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800205 char *addr, int ifindex)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700206{
207 int hash = hash_item(sid, addr);
208 struct pppox_sock *ret, **src;
209
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800210 ret = pn->hash_table[hash];
211 src = &pn->hash_table[hash];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212
213 while (ret) {
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800214 if (cmp_addr(&ret->pppoe_pa, sid, addr) &&
215 ret->pppoe_ifindex == ifindex) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216 *src = ret->next;
217 break;
218 }
219
220 src = &ret->next;
221 ret = ret->next;
222 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700223}
224
225/**********************************************************************
226 *
227 * Set/get/delete/rehash items
228 *
229 **********************************************************************/
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800230static inline struct pppox_sock *get_item(struct pppoe_net *pn, __be16 sid,
231 unsigned char *addr, int ifindex)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232{
233 struct pppox_sock *po;
234
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800235 read_lock_bh(&pn->hash_lock);
236 po = __get_item(pn, sid, addr, ifindex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237 if (po)
238 sock_hold(sk_pppox(po));
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800239 read_unlock_bh(&pn->hash_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700240
241 return po;
242}
243
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800244static inline struct pppox_sock *get_item_by_addr(struct net *net,
245 struct sockaddr_pppox *sp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700246{
Florian Zumbiehlbfafb262007-04-20 16:56:31 -0700247 struct net_device *dev;
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800248 struct pppoe_net *pn;
Eric Dumazet1178f662009-11-01 19:51:22 +0000249 struct pppox_sock *pppox_sock = NULL;
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800250
Florian Zumbiehl90719db2007-03-02 13:16:56 -0800251 int ifindex;
252
Eric Dumazet1178f662009-11-01 19:51:22 +0000253 rcu_read_lock();
254 dev = dev_get_by_name_rcu(net, sp->sa_addr.pppoe.dev);
255 if (dev) {
256 ifindex = dev->ifindex;
Jiri Pirkobe9e9692010-04-26 01:46:12 +0000257 pn = pppoe_pernet(net);
Eric Dumazet1178f662009-11-01 19:51:22 +0000258 pppox_sock = get_item(pn, sp->sa_addr.pppoe.sid,
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800259 sp->sa_addr.pppoe.remote, ifindex);
Eric Dumazet1178f662009-11-01 19:51:22 +0000260 }
261 rcu_read_unlock();
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800262 return pppox_sock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700263}
264
Rami Rosen3b12bb62012-05-17 05:04:50 +0000265static inline void delete_item(struct pppoe_net *pn, __be16 sid,
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800266 char *addr, int ifindex)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700267{
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800268 write_lock_bh(&pn->hash_lock);
Rami Rosen3b12bb62012-05-17 05:04:50 +0000269 __delete_item(pn, sid, addr, ifindex);
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800270 write_unlock_bh(&pn->hash_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271}
272
Linus Torvalds1da177e2005-04-16 15:20:36 -0700273/***************************************************************************
274 *
275 * Handler for device events.
276 * Certain device events require that sockets be unconnected.
277 *
278 **************************************************************************/
279
280static void pppoe_flush_dev(struct net_device *dev)
281{
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800282 struct pppoe_net *pn;
283 int i;
284
Dan Carpentera5e93152010-05-22 10:27:48 +0000285 pn = pppoe_pernet(dev_net(dev));
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800286 write_lock_bh(&pn->hash_lock);
287 for (i = 0; i < PPPOE_HASH_SIZE; i++) {
288 struct pppox_sock *po = pn->hash_table[i];
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700289 struct sock *sk;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700291 while (po) {
292 while (po && po->pppoe_dev != dev) {
Michal Ostrowski42dc9cd2007-04-20 16:59:24 -0700293 po = po->next;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294 }
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700295
296 if (!po)
297 break;
298
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800299 sk = sk_pppox(po);
Michal Ostrowski42dc9cd2007-04-20 16:59:24 -0700300
Michal Ostrowski42dc9cd2007-04-20 16:59:24 -0700301 /* We always grab the socket lock, followed by the
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700302 * hash_lock, in that order. Since we should hold the
303 * sock lock while doing any unbinding, we need to
304 * release the lock we're holding. Hold a reference to
305 * the sock so it doesn't disappear as we're jumping
306 * between locks.
Michal Ostrowski42dc9cd2007-04-20 16:59:24 -0700307 */
308
309 sock_hold(sk);
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800310 write_unlock_bh(&pn->hash_lock);
Michal Ostrowski42dc9cd2007-04-20 16:59:24 -0700311 lock_sock(sk);
312
Joe Perches8e95a202009-12-03 07:58:21 +0000313 if (po->pppoe_dev == dev &&
Ulrich Weberae07b0b2011-04-06 14:04:49 -0700314 sk->sk_state & (PPPOX_CONNECTED | PPPOX_BOUND | PPPOX_ZOMBIE)) {
Michal Ostrowski42dc9cd2007-04-20 16:59:24 -0700315 pppox_unbind_sock(sk);
316 sk->sk_state = PPPOX_ZOMBIE;
317 sk->sk_state_change(sk);
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700318 po->pppoe_dev = NULL;
319 dev_put(dev);
Michal Ostrowski42dc9cd2007-04-20 16:59:24 -0700320 }
321
322 release_sock(sk);
323 sock_put(sk);
324
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700325 /* Restart the process from the start of the current
326 * hash chain. We dropped locks so the world may have
327 * change from underneath us.
Michal Ostrowski42dc9cd2007-04-20 16:59:24 -0700328 */
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700329
330 BUG_ON(pppoe_pernet(dev_net(dev)) == NULL);
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800331 write_lock_bh(&pn->hash_lock);
332 po = pn->hash_table[i];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700333 }
334 }
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800335 write_unlock_bh(&pn->hash_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336}
337
338static int pppoe_device_event(struct notifier_block *this,
339 unsigned long event, void *ptr)
340{
Jiri Pirko351638e2013-05-28 01:30:21 +0000341 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
Eric W. Biedermane9dc8652007-09-12 13:02:17 +0200342
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343 /* Only look at sockets that are using this specific device. */
344 switch (event) {
David S. Miller680ba7c2011-07-18 11:48:28 -0700345 case NETDEV_CHANGEADDR:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346 case NETDEV_CHANGEMTU:
David S. Miller680ba7c2011-07-18 11:48:28 -0700347 /* A change in mtu or address is a bad thing, requiring
Linus Torvalds1da177e2005-04-16 15:20:36 -0700348 * LCP re-negotiation.
349 */
350
351 case NETDEV_GOING_DOWN:
352 case NETDEV_DOWN:
353 /* Find every socket on this device and kill it. */
354 pppoe_flush_dev(dev);
355 break;
356
357 default:
358 break;
Joe Perchesee289b62010-05-17 22:47:34 -0700359 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700360
361 return NOTIFY_DONE;
362}
363
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364static struct notifier_block pppoe_notifier = {
365 .notifier_call = pppoe_device_event,
366};
367
Linus Torvalds1da177e2005-04-16 15:20:36 -0700368/************************************************************************
369 *
370 * Do the real work of receiving a PPPoE Session frame.
371 *
372 ***********************************************************************/
373static int pppoe_rcv_core(struct sock *sk, struct sk_buff *skb)
374{
375 struct pppox_sock *po = pppox_sk(sk);
Florian Zumbiehlbfafb262007-04-20 16:56:31 -0700376 struct pppox_sock *relay_po;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700378 /* Backlog receive. Semantics of backlog rcv preclude any code from
379 * executing in lock_sock()/release_sock() bounds; meaning sk->sk_state
380 * can't change.
381 */
382
Joakim Tjernlunda0688332015-04-20 21:07:48 +0200383 if (skb->pkt_type == PACKET_OTHERHOST)
384 goto abort_kfree;
385
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386 if (sk->sk_state & PPPOX_BOUND) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700387 ppp_input(&po->chan, skb);
388 } else if (sk->sk_state & PPPOX_RELAY) {
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700389 relay_po = get_item_by_addr(sock_net(sk),
390 &po->pppoe_relay);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391 if (relay_po == NULL)
392 goto abort_kfree;
393
394 if ((sk_pppox(relay_po)->sk_state & PPPOX_CONNECTED) == 0)
395 goto abort_put;
396
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397 if (!__pppoe_xmit(sk_pppox(relay_po), skb))
398 goto abort_put;
399 } else {
400 if (sock_queue_rcv_skb(sk, skb))
401 goto abort_kfree;
402 }
403
404 return NET_RX_SUCCESS;
405
406abort_put:
407 sock_put(sk_pppox(relay_po));
408
409abort_kfree:
410 kfree_skb(skb);
411 return NET_RX_DROP;
412}
413
414/************************************************************************
415 *
416 * Receive wrapper called in BH context.
417 *
418 ***********************************************************************/
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800419static int pppoe_rcv(struct sk_buff *skb, struct net_device *dev,
420 struct packet_type *pt, struct net_device *orig_dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700421{
422 struct pppoe_hdr *ph;
423 struct pppox_sock *po;
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800424 struct pppoe_net *pn;
Herbert Xu392fdb02008-06-10 14:07:25 -0700425 int len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700426
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800427 skb = skb_share_check(skb, GFP_ATOMIC);
428 if (!skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700429 goto out;
430
Herbert Xu31bac442007-09-16 16:19:20 -0700431 if (!pskb_may_pull(skb, sizeof(struct pppoe_hdr)))
432 goto drop;
433
Arnaldo Carvalho de Melo797659f2007-03-10 15:56:08 -0300434 ph = pppoe_hdr(skb);
Herbert Xu392fdb02008-06-10 14:07:25 -0700435 len = ntohs(ph->length);
436
437 skb_pull_rcsum(skb, sizeof(*ph));
438 if (skb->len < len)
439 goto drop;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700440
David S. Miller263e69c2008-10-30 23:11:44 -0700441 if (pskb_trim_rcsum(skb, len))
Herbert Xu392fdb02008-06-10 14:07:25 -0700442 goto drop;
443
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800444 pn = pppoe_pernet(dev_net(dev));
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700445
446 /* Note that get_item does a sock_hold(), so sk_pppox(po)
447 * is known to be safe.
448 */
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800449 po = get_item(pn, ph->sid, eth_hdr(skb)->h_source, dev->ifindex);
David S. Miller263e69c2008-10-30 23:11:44 -0700450 if (!po)
Herbert Xu392fdb02008-06-10 14:07:25 -0700451 goto drop;
452
453 return sk_receive_skb(sk_pppox(po), skb, 0);
454
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455drop:
456 kfree_skb(skb);
457out:
458 return NET_RX_DROP;
459}
460
Simon Farnsworth287f3a92015-03-01 10:54:39 +0000461static void pppoe_unbind_sock_work(struct work_struct *work)
462{
463 struct pppox_sock *po = container_of(work, struct pppox_sock,
464 proto.pppoe.padt_work);
465 struct sock *sk = sk_pppox(po);
466
467 lock_sock(sk);
Felix Fietkau665a6cd2015-05-09 23:08:38 +0200468 if (po->pppoe_dev) {
469 dev_put(po->pppoe_dev);
470 po->pppoe_dev = NULL;
471 }
Simon Farnsworth287f3a92015-03-01 10:54:39 +0000472 pppox_unbind_sock(sk);
473 release_sock(sk);
474 sock_put(sk);
475}
476
Linus Torvalds1da177e2005-04-16 15:20:36 -0700477/************************************************************************
478 *
479 * Receive a PPPoE Discovery frame.
480 * This is solely for detection of PADT frames
481 *
482 ***********************************************************************/
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800483static int pppoe_disc_rcv(struct sk_buff *skb, struct net_device *dev,
484 struct packet_type *pt, struct net_device *orig_dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700485
486{
487 struct pppoe_hdr *ph;
488 struct pppox_sock *po;
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800489 struct pppoe_net *pn;
Eric W. Biedermane730c152007-09-17 11:53:39 -0700490
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800491 skb = skb_share_check(skb, GFP_ATOMIC);
492 if (!skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700493 goto out;
494
Herbert Xubc6cffd12008-06-10 14:08:25 -0700495 if (!pskb_may_pull(skb, sizeof(struct pppoe_hdr)))
496 goto abort;
497
Arnaldo Carvalho de Melo797659f2007-03-10 15:56:08 -0300498 ph = pppoe_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700499 if (ph->code != PADT_CODE)
500 goto abort;
501
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800502 pn = pppoe_pernet(dev_net(dev));
503 po = get_item(pn, ph->sid, eth_hdr(skb)->h_source, dev->ifindex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700504 if (po) {
505 struct sock *sk = sk_pppox(po);
506
507 bh_lock_sock(sk);
508
509 /* If the user has locked the socket, just ignore
510 * the packet. With the way two rcv protocols hook into
511 * one socket family type, we cannot (easily) distinguish
512 * what kind of SKB it is during backlog rcv.
513 */
514 if (sock_owned_by_user(sk) == 0) {
515 /* We're no longer connect at the PPPOE layer,
516 * and must wait for ppp channel to disconnect us.
517 */
518 sk->sk_state = PPPOX_ZOMBIE;
519 }
520
521 bh_unlock_sock(sk);
Simon Farnsworth287f3a92015-03-01 10:54:39 +0000522 if (!schedule_work(&po->proto.pppoe.padt_work))
523 sock_put(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700524 }
525
526abort:
527 kfree_skb(skb);
528out:
529 return NET_RX_SUCCESS; /* Lies... :-) */
530}
531
Stephen Hemminger7546dd92009-03-09 08:18:29 +0000532static struct packet_type pppoes_ptype __read_mostly = {
Harvey Harrison09640e62009-02-01 00:45:17 -0800533 .type = cpu_to_be16(ETH_P_PPP_SES),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700534 .func = pppoe_rcv,
535};
536
Stephen Hemminger7546dd92009-03-09 08:18:29 +0000537static struct packet_type pppoed_ptype __read_mostly = {
Harvey Harrison09640e62009-02-01 00:45:17 -0800538 .type = cpu_to_be16(ETH_P_PPP_DISC),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700539 .func = pppoe_disc_rcv,
540};
541
Stephen Hemminger7546dd92009-03-09 08:18:29 +0000542static struct proto pppoe_sk_proto __read_mostly = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700543 .name = "PPPOE",
544 .owner = THIS_MODULE,
545 .obj_size = sizeof(struct pppox_sock),
546};
547
548/***********************************************************************
549 *
550 * Initialize a new struct sock.
551 *
552 **********************************************************************/
Eric W. Biederman1b8d7ae2007-10-08 23:24:22 -0700553static int pppoe_create(struct net *net, struct socket *sock)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700554{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700555 struct sock *sk;
556
Pavel Emelyanov6257ff22007-11-01 00:39:31 -0700557 sk = sk_alloc(net, PF_PPPOX, GFP_KERNEL, &pppoe_sk_proto);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700558 if (!sk)
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800559 return -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560
561 sock_init_data(sock, sk);
562
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800563 sock->state = SS_UNCONNECTED;
564 sock->ops = &pppoe_ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800566 sk->sk_backlog_rcv = pppoe_rcv_core;
567 sk->sk_state = PPPOX_NONE;
568 sk->sk_type = SOCK_STREAM;
569 sk->sk_family = PF_PPPOX;
570 sk->sk_protocol = PX_PROTO_OE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700571
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800572 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700573}
574
575static int pppoe_release(struct socket *sock)
576{
577 struct sock *sk = sock->sk;
578 struct pppox_sock *po;
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800579 struct pppoe_net *pn;
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700580 struct net *net = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700581
582 if (!sk)
583 return 0;
584
Michal Ostrowski42dc9cd2007-04-20 16:59:24 -0700585 lock_sock(sk);
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800586 if (sock_flag(sk, SOCK_DEAD)) {
Michal Ostrowski42dc9cd2007-04-20 16:59:24 -0700587 release_sock(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700588 return -EBADF;
Michal Ostrowski42dc9cd2007-04-20 16:59:24 -0700589 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700591 po = pppox_sk(sk);
592
Xiaodong Xu2b018d52012-09-22 00:09:32 +0000593 if (sk->sk_state & (PPPOX_CONNECTED | PPPOX_BOUND | PPPOX_ZOMBIE)) {
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700594 dev_put(po->pppoe_dev);
595 po->pppoe_dev = NULL;
596 }
597
Linus Torvalds1da177e2005-04-16 15:20:36 -0700598 pppox_unbind_sock(sk);
599
600 /* Signal the death of the socket. */
601 sk->sk_state = PPPOX_DEAD;
602
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700603 net = sock_net(sk);
604 pn = pppoe_pernet(net);
Michal Ostrowski42dc9cd2007-04-20 16:59:24 -0700605
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800606 /*
607 * protect "po" from concurrent updates
608 * on pppoe_flush_dev
609 */
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700610 delete_item(pn, po->pppoe_pa.sid, po->pppoe_pa.remote,
611 po->pppoe_ifindex);
Michal Ostrowski42dc9cd2007-04-20 16:59:24 -0700612
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613 sock_orphan(sk);
614 sock->sk = NULL;
615
616 skb_queue_purge(&sk->sk_receive_queue);
Michal Ostrowski42dc9cd2007-04-20 16:59:24 -0700617 release_sock(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618 sock_put(sk);
619
Florian Zumbiehlbfafb262007-04-20 16:56:31 -0700620 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700621}
622
Linus Torvalds1da177e2005-04-16 15:20:36 -0700623static int pppoe_connect(struct socket *sock, struct sockaddr *uservaddr,
624 int sockaddr_len, int flags)
625{
626 struct sock *sk = sock->sk;
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800627 struct sockaddr_pppox *sp = (struct sockaddr_pppox *)uservaddr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700628 struct pppox_sock *po = pppox_sk(sk);
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700629 struct net_device *dev = NULL;
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800630 struct pppoe_net *pn;
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700631 struct net *net = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700632 int error;
633
634 lock_sock(sk);
635
Simon Farnsworth287f3a92015-03-01 10:54:39 +0000636 INIT_WORK(&po->proto.pppoe.padt_work, pppoe_unbind_sock_work);
637
Linus Torvalds1da177e2005-04-16 15:20:36 -0700638 error = -EINVAL;
639 if (sp->sa_protocol != PX_PROTO_OE)
640 goto end;
641
642 /* Check for already bound sockets */
643 error = -EBUSY;
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800644 if ((sk->sk_state & PPPOX_CONNECTED) &&
645 stage_session(sp->sa_addr.pppoe.sid))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700646 goto end;
647
648 /* Check for already disconnected sockets, on attempts to disconnect */
649 error = -EALREADY;
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800650 if ((sk->sk_state & PPPOX_DEAD) &&
651 !stage_session(sp->sa_addr.pppoe.sid))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700652 goto end;
653
654 error = 0;
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800655
656 /* Delete the old binding */
657 if (stage_session(po->pppoe_pa.sid)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700658 pppox_unbind_sock(sk);
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700659 pn = pppoe_pernet(sock_net(sk));
660 delete_item(pn, po->pppoe_pa.sid,
661 po->pppoe_pa.remote, po->pppoe_ifindex);
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800662 if (po->pppoe_dev) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663 dev_put(po->pppoe_dev);
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700664 po->pppoe_dev = NULL;
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800665 }
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700666
Linus Torvalds1da177e2005-04-16 15:20:36 -0700667 memset(sk_pppox(po) + 1, 0,
668 sizeof(struct pppox_sock) - sizeof(struct sock));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700669 sk->sk_state = PPPOX_NONE;
670 }
671
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800672 /* Re-bind in session stage only */
673 if (stage_session(sp->sa_addr.pppoe.sid)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700674 error = -ENODEV;
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700675 net = sock_net(sk);
676 dev = dev_get_by_name(net, sp->sa_addr.pppoe.dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700677 if (!dev)
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700678 goto err_put;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700679
680 po->pppoe_dev = dev;
Florian Zumbiehl6f30e182007-03-04 16:03:22 -0800681 po->pppoe_ifindex = dev->ifindex;
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700682 pn = pppoe_pernet(net);
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800683 if (!(dev->flags & IFF_UP)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700684 goto err_put;
Florian Zumbiehl74b885c2007-04-20 16:57:27 -0700685 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686
687 memcpy(&po->pppoe_pa,
688 &sp->sa_addr.pppoe,
689 sizeof(struct pppoe_addr));
690
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700691 write_lock_bh(&pn->hash_lock);
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800692 error = __set_item(pn, po);
693 write_unlock_bh(&pn->hash_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700694 if (error < 0)
695 goto err_put;
696
697 po->chan.hdrlen = (sizeof(struct pppoe_hdr) +
698 dev->hard_header_len);
699
Christoph Schulza8a3e412014-07-13 00:53:15 +0200700 po->chan.mtu = dev->mtu - sizeof(struct pppoe_hdr) - 2;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700701 po->chan.private = sk;
702 po->chan.ops = &pppoe_chan_ops;
703
Cyrill Gorcunovf5882c32009-01-21 15:55:40 -0800704 error = ppp_register_net_channel(dev_net(dev), &po->chan);
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700705 if (error) {
706 delete_item(pn, po->pppoe_pa.sid,
707 po->pppoe_pa.remote, po->pppoe_ifindex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700708 goto err_put;
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700709 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700710
711 sk->sk_state = PPPOX_CONNECTED;
712 }
713
714 po->num = sp->sa_addr.pppoe.sid;
715
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800716end:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700717 release_sock(sk);
718 return error;
719err_put:
720 if (po->pppoe_dev) {
721 dev_put(po->pppoe_dev);
722 po->pppoe_dev = NULL;
723 }
724 goto end;
725}
726
Linus Torvalds1da177e2005-04-16 15:20:36 -0700727static int pppoe_getname(struct socket *sock, struct sockaddr *uaddr,
728 int *usockaddr_len, int peer)
729{
730 int len = sizeof(struct sockaddr_pppox);
731 struct sockaddr_pppox sp;
732
733 sp.sa_family = AF_PPPOX;
734 sp.sa_protocol = PX_PROTO_OE;
735 memcpy(&sp.sa_addr.pppoe, &pppox_sk(sock->sk)->pppoe_pa,
736 sizeof(struct pppoe_addr));
737
738 memcpy(uaddr, &sp, len);
739
740 *usockaddr_len = len;
741
742 return 0;
743}
744
Linus Torvalds1da177e2005-04-16 15:20:36 -0700745static int pppoe_ioctl(struct socket *sock, unsigned int cmd,
746 unsigned long arg)
747{
748 struct sock *sk = sock->sk;
749 struct pppox_sock *po = pppox_sk(sk);
Florian Zumbiehl86c1dcf2007-07-30 17:48:23 -0700750 int val;
751 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700752
753 switch (cmd) {
754 case PPPIOCGMRU:
755 err = -ENXIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700756 if (!(sk->sk_state & PPPOX_CONNECTED))
757 break;
758
759 err = -EFAULT;
760 if (put_user(po->pppoe_dev->mtu -
761 sizeof(struct pppoe_hdr) -
762 PPP_HDRLEN,
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800763 (int __user *)arg))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700764 break;
765 err = 0;
766 break;
767
768 case PPPIOCSMRU:
769 err = -ENXIO;
770 if (!(sk->sk_state & PPPOX_CONNECTED))
771 break;
772
773 err = -EFAULT;
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800774 if (get_user(val, (int __user *)arg))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700775 break;
776
777 if (val < (po->pppoe_dev->mtu
778 - sizeof(struct pppoe_hdr)
779 - PPP_HDRLEN))
780 err = 0;
781 else
782 err = -EINVAL;
783 break;
784
785 case PPPIOCSFLAGS:
786 err = -EFAULT;
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800787 if (get_user(val, (int __user *)arg))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700788 break;
789 err = 0;
790 break;
791
792 case PPPOEIOCSFWD:
793 {
794 struct pppox_sock *relay_po;
795
796 err = -EBUSY;
797 if (sk->sk_state & (PPPOX_BOUND | PPPOX_ZOMBIE | PPPOX_DEAD))
798 break;
799
800 err = -ENOTCONN;
801 if (!(sk->sk_state & PPPOX_CONNECTED))
802 break;
803
804 /* PPPoE address from the user specifies an outbound
Florian Zumbiehl90719db2007-03-02 13:16:56 -0800805 PPPoE address which frames are forwarded to */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700806 err = -EFAULT;
807 if (copy_from_user(&po->pppoe_relay,
808 (void __user *)arg,
809 sizeof(struct sockaddr_pppox)))
810 break;
811
812 err = -EINVAL;
813 if (po->pppoe_relay.sa_family != AF_PPPOX ||
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800814 po->pppoe_relay.sa_protocol != PX_PROTO_OE)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700815 break;
816
817 /* Check that the socket referenced by the address
818 actually exists. */
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800819 relay_po = get_item_by_addr(sock_net(sk), &po->pppoe_relay);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700820 if (!relay_po)
821 break;
822
823 sock_put(sk_pppox(relay_po));
824 sk->sk_state |= PPPOX_RELAY;
825 err = 0;
826 break;
827 }
828
829 case PPPOEIOCDFWD:
830 err = -EALREADY;
831 if (!(sk->sk_state & PPPOX_RELAY))
832 break;
833
834 sk->sk_state &= ~PPPOX_RELAY;
835 err = 0;
836 break;
837
Florian Zumbiehl86c1dcf2007-07-30 17:48:23 -0700838 default:
839 err = -ENOTTY;
840 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700841
842 return err;
843}
844
Ying Xue1b784142015-03-02 15:37:48 +0800845static int pppoe_sendmsg(struct socket *sock, struct msghdr *m,
846 size_t total_len)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700847{
Florian Zumbiehlbfafb262007-04-20 16:56:31 -0700848 struct sk_buff *skb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700849 struct sock *sk = sock->sk;
850 struct pppox_sock *po = pppox_sk(sk);
Florian Zumbiehlbfafb262007-04-20 16:56:31 -0700851 int error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700852 struct pppoe_hdr hdr;
853 struct pppoe_hdr *ph;
854 struct net_device *dev;
855 char *start;
856
Florian Zumbiehl8aeca8f2007-07-30 17:49:13 -0700857 lock_sock(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700858 if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED)) {
859 error = -ENOTCONN;
860 goto end;
861 }
862
863 hdr.ver = 1;
864 hdr.type = 1;
865 hdr.code = 0;
866 hdr.sid = po->num;
867
Linus Torvalds1da177e2005-04-16 15:20:36 -0700868 dev = po->pppoe_dev;
869
870 error = -EMSGSIZE;
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -0800871 if (total_len > (dev->mtu + dev->hard_header_len))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700872 goto end;
873
874
875 skb = sock_wmalloc(sk, total_len + dev->hard_header_len + 32,
876 0, GFP_KERNEL);
877 if (!skb) {
878 error = -ENOMEM;
879 goto end;
880 }
881
882 /* Reserve space for headers. */
883 skb_reserve(skb, dev->hard_header_len);
Arnaldo Carvalho de Meloc1d2bbe2007-04-10 20:45:18 -0700884 skb_reset_network_header(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700885
886 skb->dev = dev;
887
888 skb->priority = sk->sk_priority;
Harvey Harrison09640e62009-02-01 00:45:17 -0800889 skb->protocol = cpu_to_be16(ETH_P_PPP_SES);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700890
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800891 ph = (struct pppoe_hdr *)skb_put(skb, total_len + sizeof(struct pppoe_hdr));
892 start = (char *)&ph->tag[0];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700893
Al Viro6ce8e9c2014-04-06 21:25:44 -0400894 error = memcpy_from_msg(start, m, total_len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700895 if (error < 0) {
896 kfree_skb(skb);
897 goto end;
898 }
899
900 error = total_len;
Stephen Hemminger0c4e8582007-10-09 01:36:32 -0700901 dev_hard_header(skb, dev, ETH_P_PPP_SES,
902 po->pppoe_pa.remote, NULL, total_len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700903
904 memcpy(ph, &hdr, sizeof(struct pppoe_hdr));
905
906 ph->length = htons(total_len);
907
908 dev_queue_xmit(skb);
909
910end:
911 release_sock(sk);
912 return error;
913}
914
Linus Torvalds1da177e2005-04-16 15:20:36 -0700915/************************************************************************
916 *
917 * xmit function for internal use.
918 *
919 ***********************************************************************/
920static int __pppoe_xmit(struct sock *sk, struct sk_buff *skb)
921{
922 struct pppox_sock *po = pppox_sk(sk);
923 struct net_device *dev = po->pppoe_dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700924 struct pppoe_hdr *ph;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700925 int data_len = skb->len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700926
Michal Ostrowskifb64bb52009-10-26 16:23:20 -0700927 /* The higher-level PPP code (ppp_unregister_channel()) ensures the PPP
928 * xmit operations conclude prior to an unregistration call. Thus
929 * sk->sk_state cannot change, so we don't need to do lock_sock().
930 * But, we also can't do a lock_sock since that introduces a potential
931 * deadlock as we'd reverse the lock ordering used when calling
932 * ppp_unregister_channel().
933 */
934
Linus Torvalds1da177e2005-04-16 15:20:36 -0700935 if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED))
936 goto abort;
937
Linus Torvalds1da177e2005-04-16 15:20:36 -0700938 if (!dev)
939 goto abort;
940
Herbert Xudb7bf6d2007-09-16 16:19:50 -0700941 /* Copy the data if there is no space for the header or if it's
942 * read-only.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700943 */
Herbert Xud9cc2042007-09-16 16:21:16 -0700944 if (skb_cow_head(skb, sizeof(*ph) + dev->hard_header_len))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700945 goto abort;
946
Herbert Xu9355ec22007-09-16 16:20:21 -0700947 __skb_push(skb, sizeof(*ph));
Herbert Xudb7bf6d2007-09-16 16:19:50 -0700948 skb_reset_network_header(skb);
949
Herbert Xu9355ec22007-09-16 16:20:21 -0700950 ph = pppoe_hdr(skb);
951 ph->ver = 1;
952 ph->type = 1;
953 ph->code = 0;
954 ph->sid = po->num;
955 ph->length = htons(data_len);
956
Harvey Harrison09640e62009-02-01 00:45:17 -0800957 skb->protocol = cpu_to_be16(ETH_P_PPP_SES);
Herbert Xudb7bf6d2007-09-16 16:19:50 -0700958 skb->dev = dev;
959
Stephen Hemminger0c4e8582007-10-09 01:36:32 -0700960 dev_hard_header(skb, dev, ETH_P_PPP_SES,
961 po->pppoe_pa.remote, NULL, data_len);
Herbert Xudb7bf6d2007-09-16 16:19:50 -0700962
Herbert Xu21d0c832007-09-19 10:45:02 -0700963 dev_queue_xmit(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700964 return 1;
965
966abort:
Herbert Xudb7bf6d2007-09-16 16:19:50 -0700967 kfree_skb(skb);
Andrej Ota2a27a032010-12-12 15:06:16 -0800968 return 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700969}
970
Linus Torvalds1da177e2005-04-16 15:20:36 -0700971/************************************************************************
972 *
973 * xmit function called by generic PPP driver
974 * sends PPP frame over PPPoE socket
975 *
976 ***********************************************************************/
977static int pppoe_xmit(struct ppp_channel *chan, struct sk_buff *skb)
978{
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -0800979 struct sock *sk = (struct sock *)chan->private;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700980 return __pppoe_xmit(sk, skb);
981}
982
stephen hemmingerd7100da2010-08-04 07:34:36 +0000983static const struct ppp_channel_ops pppoe_chan_ops = {
Jeff Garzik6aa20a22006-09-13 13:24:59 -0400984 .start_xmit = pppoe_xmit,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700985};
986
Ying Xue1b784142015-03-02 15:37:48 +0800987static int pppoe_recvmsg(struct socket *sock, struct msghdr *m,
988 size_t total_len, int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700989{
990 struct sock *sk = sock->sk;
Florian Zumbiehlbfafb262007-04-20 16:56:31 -0700991 struct sk_buff *skb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700992 int error = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700993
994 if (sk->sk_state & PPPOX_BOUND) {
995 error = -EIO;
996 goto end;
997 }
998
999 skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
1000 flags & MSG_DONTWAIT, &error);
Florian Zumbiehlbfafb262007-04-20 16:56:31 -07001001 if (error < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001002 goto end;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001003
Linus Torvalds1da177e2005-04-16 15:20:36 -07001004 if (skb) {
Stephen Hemminger2645a3c2008-06-20 21:58:02 -07001005 total_len = min_t(size_t, total_len, skb->len);
David S. Miller51f3d022014-11-05 16:46:40 -05001006 error = skb_copy_datagram_msg(skb, 0, m, total_len);
Eric Dumazet968d7012012-05-18 20:23:00 +00001007 if (error == 0) {
1008 consume_skb(skb);
1009 return total_len;
1010 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001011 }
1012
Arnaldo Carvalho de Melo797659f2007-03-10 15:56:08 -03001013 kfree_skb(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001014end:
1015 return error;
1016}
1017
1018#ifdef CONFIG_PROC_FS
1019static int pppoe_seq_show(struct seq_file *seq, void *v)
1020{
1021 struct pppox_sock *po;
1022 char *dev_name;
1023
1024 if (v == SEQ_START_TOKEN) {
1025 seq_puts(seq, "Id Address Device\n");
1026 goto out;
1027 }
1028
1029 po = v;
1030 dev_name = po->pppoe_pa.dev;
1031
Johannes Berge1749612008-10-27 15:59:26 -07001032 seq_printf(seq, "%08X %pM %8s\n",
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -08001033 po->pppoe_pa.sid, po->pppoe_pa.remote, dev_name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001034out:
1035 return 0;
1036}
1037
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -08001038static inline struct pppox_sock *pppoe_get_idx(struct pppoe_net *pn, loff_t pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001039{
Florian Zumbiehlbfafb262007-04-20 16:56:31 -07001040 struct pppox_sock *po;
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -08001041 int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001042
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -08001043 for (i = 0; i < PPPOE_HASH_SIZE; i++) {
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -08001044 po = pn->hash_table[i];
Linus Torvalds1da177e2005-04-16 15:20:36 -07001045 while (po) {
1046 if (!pos--)
1047 goto out;
1048 po = po->next;
1049 }
1050 }
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -08001051
Linus Torvalds1da177e2005-04-16 15:20:36 -07001052out:
1053 return po;
1054}
1055
1056static void *pppoe_seq_start(struct seq_file *seq, loff_t *pos)
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -08001057 __acquires(pn->hash_lock)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001058{
Cyrill Gorcunov3617aa42009-01-26 21:11:02 -08001059 struct pppoe_net *pn = pppoe_pernet(seq_file_net(seq));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001060 loff_t l = *pos;
1061
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -08001062 read_lock_bh(&pn->hash_lock);
1063 return l ? pppoe_get_idx(pn, --l) : SEQ_START_TOKEN;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001064}
1065
1066static void *pppoe_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1067{
Cyrill Gorcunov3617aa42009-01-26 21:11:02 -08001068 struct pppoe_net *pn = pppoe_pernet(seq_file_net(seq));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001069 struct pppox_sock *po;
1070
1071 ++*pos;
1072 if (v == SEQ_START_TOKEN) {
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -08001073 po = pppoe_get_idx(pn, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001074 goto out;
1075 }
1076 po = v;
Jeff Garzik6aa20a22006-09-13 13:24:59 -04001077 if (po->next)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001078 po = po->next;
1079 else {
1080 int hash = hash_item(po->pppoe_pa.sid, po->pppoe_pa.remote);
1081
Eric Dumazet72fc9392009-07-28 23:43:08 +00001082 po = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001083 while (++hash < PPPOE_HASH_SIZE) {
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -08001084 po = pn->hash_table[hash];
Linus Torvalds1da177e2005-04-16 15:20:36 -07001085 if (po)
1086 break;
1087 }
1088 }
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -08001089
Linus Torvalds1da177e2005-04-16 15:20:36 -07001090out:
1091 return po;
1092}
1093
1094static void pppoe_seq_stop(struct seq_file *seq, void *v)
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -08001095 __releases(pn->hash_lock)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001096{
Cyrill Gorcunov3617aa42009-01-26 21:11:02 -08001097 struct pppoe_net *pn = pppoe_pernet(seq_file_net(seq));
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -08001098 read_unlock_bh(&pn->hash_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001099}
1100
Jan Engelhardt4101dec2009-01-14 13:52:18 -08001101static const struct seq_operations pppoe_seq_ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001102 .start = pppoe_seq_start,
1103 .next = pppoe_seq_next,
1104 .stop = pppoe_seq_stop,
1105 .show = pppoe_seq_show,
1106};
1107
1108static int pppoe_seq_open(struct inode *inode, struct file *file)
1109{
Cyrill Gorcunov3617aa42009-01-26 21:11:02 -08001110 return seq_open_net(inode, file, &pppoe_seq_ops,
1111 sizeof(struct seq_net_private));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001112}
1113
Arjan van de Vend54b1fd2007-02-12 00:55:34 -08001114static const struct file_operations pppoe_seq_fops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001115 .owner = THIS_MODULE,
1116 .open = pppoe_seq_open,
1117 .read = seq_read,
1118 .llseek = seq_lseek,
Cyrill Gorcunov3617aa42009-01-26 21:11:02 -08001119 .release = seq_release_net,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001120};
1121
Linus Torvalds1da177e2005-04-16 15:20:36 -07001122#endif /* CONFIG_PROC_FS */
1123
David S. Miller17ba15f2005-12-27 20:57:40 -08001124static const struct proto_ops pppoe_ops = {
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -08001125 .family = AF_PPPOX,
1126 .owner = THIS_MODULE,
1127 .release = pppoe_release,
1128 .bind = sock_no_bind,
1129 .connect = pppoe_connect,
1130 .socketpair = sock_no_socketpair,
1131 .accept = sock_no_accept,
1132 .getname = pppoe_getname,
1133 .poll = datagram_poll,
1134 .listen = sock_no_listen,
1135 .shutdown = sock_no_shutdown,
1136 .setsockopt = sock_no_setsockopt,
1137 .getsockopt = sock_no_getsockopt,
1138 .sendmsg = pppoe_sendmsg,
1139 .recvmsg = pppoe_recvmsg,
1140 .mmap = sock_no_mmap,
1141 .ioctl = pppox_ioctl,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001142};
1143
Eric Dumazet756e64a2010-09-21 06:43:54 +00001144static const struct pppox_proto pppoe_proto = {
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -08001145 .create = pppoe_create,
1146 .ioctl = pppoe_ioctl,
1147 .owner = THIS_MODULE,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001148};
1149
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -08001150static __net_init int pppoe_init_net(struct net *net)
1151{
Eric W. Biedermanc879a6f2009-11-29 15:46:10 +00001152 struct pppoe_net *pn = pppoe_pernet(net);
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -08001153 struct proc_dir_entry *pde;
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -08001154
1155 rwlock_init(&pn->hash_lock);
1156
Gao fengd4beaa62013-02-18 01:34:54 +00001157 pde = proc_create("pppoe", S_IRUGO, net->proc_net, &pppoe_seq_fops);
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -08001158#ifdef CONFIG_PROC_FS
Eric W. Biedermanc879a6f2009-11-29 15:46:10 +00001159 if (!pde)
1160 return -ENOMEM;
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -08001161#endif
1162
1163 return 0;
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -08001164}
1165
1166static __net_exit void pppoe_exit_net(struct net *net)
1167{
Gao fengece31ff2013-02-18 01:34:56 +00001168 remove_proc_entry("pppoe", net->proc_net);
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -08001169}
1170
Alexey Dobriyan00129852009-02-09 18:05:16 -08001171static struct pernet_operations pppoe_net_ops = {
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -08001172 .init = pppoe_init_net,
1173 .exit = pppoe_exit_net,
Eric W. Biedermanc879a6f2009-11-29 15:46:10 +00001174 .id = &pppoe_net_id,
1175 .size = sizeof(struct pppoe_net),
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -08001176};
1177
Linus Torvalds1da177e2005-04-16 15:20:36 -07001178static int __init pppoe_init(void)
1179{
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -08001180 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001181
Eric W. Biedermanc879a6f2009-11-29 15:46:10 +00001182 err = register_pernet_device(&pppoe_net_ops);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001183 if (err)
1184 goto out;
1185
Cyrill Gorcunov07f66422009-08-12 16:39:16 -07001186 err = proto_register(&pppoe_sk_proto, 0);
1187 if (err)
1188 goto out_unregister_net_ops;
1189
Cyrill Gorcunov6aba9152009-01-21 15:54:15 -08001190 err = register_pppox_proto(PX_PROTO_OE, &pppoe_proto);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001191 if (err)
1192 goto out_unregister_pppoe_proto;
1193
Linus Torvalds1da177e2005-04-16 15:20:36 -07001194 dev_add_pack(&pppoes_ptype);
1195 dev_add_pack(&pppoed_ptype);
1196 register_netdevice_notifier(&pppoe_notifier);
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -08001197
1198 return 0;
1199
Linus Torvalds1da177e2005-04-16 15:20:36 -07001200out_unregister_pppoe_proto:
1201 proto_unregister(&pppoe_sk_proto);
Cyrill Gorcunov07f66422009-08-12 16:39:16 -07001202out_unregister_net_ops:
Eric W. Biedermanc879a6f2009-11-29 15:46:10 +00001203 unregister_pernet_device(&pppoe_net_ops);
Cyrill Gorcunova6bcf1c2009-01-21 15:54:54 -08001204out:
1205 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001206}
1207
1208static void __exit pppoe_exit(void)
1209{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001210 unregister_netdevice_notifier(&pppoe_notifier);
Cyrill Gorcunov07f66422009-08-12 16:39:16 -07001211 dev_remove_pack(&pppoed_ptype);
1212 dev_remove_pack(&pppoes_ptype);
1213 unregister_pppox_proto(PX_PROTO_OE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001214 proto_unregister(&pppoe_sk_proto);
Eric W. Biedermanc879a6f2009-11-29 15:46:10 +00001215 unregister_pernet_device(&pppoe_net_ops);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001216}
1217
1218module_init(pppoe_init);
1219module_exit(pppoe_exit);
1220
1221MODULE_AUTHOR("Michal Ostrowski <mostrows@speakeasy.net>");
1222MODULE_DESCRIPTION("PPP over Ethernet driver");
1223MODULE_LICENSE("GPL");
1224MODULE_ALIAS_NETPROTO(PF_PPPOX);