blob: ce1a9bf7b9a76ee1d2d0172c4092de0473a653c7 [file] [log] [blame]
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 *
10 * 220102 : Fix module use count on failure in pppoe_create, pppox_sk -acme
11 * 030700 : Fixed connect logic to allow for disconnect.
12 * 270700 : Fixed potential SMP problems; we must protect against
13 * simultaneous invocation of ppp_input
14 * and ppp_unregister_channel.
15 * 040800 : Respect reference count mechanisms on net-devices.
16 * 200800 : fix kfree(skb) in pppoe_rcv (acme)
17 * Module reference count is decremented in the right spot now,
18 * guards against sock_put not actually freeing the sk
19 * in pppoe_release.
20 * 051000 : Initialization cleanup.
21 * 111100 : Fix recvmsg.
22 * 050101 : Fix PADT procesing.
23 * 140501 : Use pppoe_rcv_core to handle all backlog. (Alexey)
24 * 170701 : Do not lock_sock with rwlock held. (DaveM)
25 * Ignore discovery frames if user has socket
26 * locked. (DaveM)
27 * Ignore return value of dev_queue_xmit in __pppoe_xmit
28 * or else we may kfree an SKB twice. (DaveM)
29 * 190701 : When doing copies of skb's in __pppoe_xmit, always delete
30 * the original skb that was passed in on success, never on
31 * failure. Delete the copy of the skb on failure to avoid
32 * a memory leak.
33 * 081001 : Misc. cleanup (licence string, non-blocking, prevent
34 * reference of device on close).
35 * 121301 : New ppp channels interface; cannot unregister a channel
36 * from interrupts. Thus, we mark the socket as a ZOMBIE
37 * and do the unregistration later.
38 * 081002 : seq_file support for proc stuff -acme
39 * 111602 : Merge all 2.4 fixes into 2.5/2.6 tree. Label 2.5/2.6
40 * as version 0.7. Spacing cleanup.
41 * Author: Michal Ostrowski <mostrows@speakeasy.net>
42 * Contributors:
43 * Arnaldo Carvalho de Melo <acme@conectiva.com.br>
44 * David S. Miller (davem@redhat.com)
45 *
46 * License:
47 * This program is free software; you can redistribute it and/or
48 * modify it under the terms of the GNU General Public License
49 * as published by the Free Software Foundation; either version
50 * 2 of the License, or (at your option) any later version.
51 *
52 */
53
54#include <linux/string.h>
55#include <linux/module.h>
56#include <linux/kernel.h>
57#include <linux/slab.h>
58#include <linux/errno.h>
59#include <linux/netdevice.h>
60#include <linux/net.h>
61#include <linux/inetdevice.h>
62#include <linux/etherdevice.h>
63#include <linux/skbuff.h>
64#include <linux/init.h>
65#include <linux/if_ether.h>
66#include <linux/if_pppox.h>
67#include <linux/ppp_channel.h>
68#include <linux/ppp_defs.h>
69#include <linux/if_ppp.h>
70#include <linux/notifier.h>
71#include <linux/file.h>
72#include <linux/proc_fs.h>
73#include <linux/seq_file.h>
74
75#include <net/sock.h>
76
77#include <asm/uaccess.h>
78
79#define PPPOE_HASH_BITS 4
80#define PPPOE_HASH_SIZE (1<<PPPOE_HASH_BITS)
81
82static struct ppp_channel_ops pppoe_chan_ops;
83
84static int pppoe_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg);
85static int pppoe_xmit(struct ppp_channel *chan, struct sk_buff *skb);
86static int __pppoe_xmit(struct sock *sk, struct sk_buff *skb);
87
88static struct proto_ops pppoe_ops;
89static DEFINE_RWLOCK(pppoe_hash_lock);
90
91static struct ppp_channel_ops pppoe_chan_ops;
92
93static inline int cmp_2_addr(struct pppoe_addr *a, struct pppoe_addr *b)
94{
95 return (a->sid == b->sid &&
96 (memcmp(a->remote, b->remote, ETH_ALEN) == 0));
97}
98
99static inline int cmp_addr(struct pppoe_addr *a, unsigned long sid, char *addr)
100{
101 return (a->sid == sid &&
102 (memcmp(a->remote,addr,ETH_ALEN) == 0));
103}
104
105static int hash_item(unsigned long sid, unsigned char *addr)
106{
107 char hash = 0;
108 int i, j;
109
110 for (i = 0; i < ETH_ALEN ; ++i) {
111 for (j = 0; j < 8/PPPOE_HASH_BITS ; ++j) {
112 hash ^= addr[i] >> ( j * PPPOE_HASH_BITS );
113 }
114 }
115
116 for (i = 0; i < (sizeof(unsigned long)*8) / PPPOE_HASH_BITS ; ++i)
117 hash ^= sid >> (i*PPPOE_HASH_BITS);
118
119 return hash & ( PPPOE_HASH_SIZE - 1 );
120}
121
122/* zeroed because its in .bss */
123static struct pppox_sock *item_hash_table[PPPOE_HASH_SIZE];
124
125/**********************************************************************
126 *
127 * Set/get/delete/rehash items (internal versions)
128 *
129 **********************************************************************/
130static struct pppox_sock *__get_item(unsigned long sid, unsigned char *addr)
131{
132 int hash = hash_item(sid, addr);
133 struct pppox_sock *ret;
134
135 ret = item_hash_table[hash];
136
137 while (ret && !cmp_addr(&ret->pppoe_pa, sid, addr))
138 ret = ret->next;
139
140 return ret;
141}
142
143static int __set_item(struct pppox_sock *po)
144{
145 int hash = hash_item(po->pppoe_pa.sid, po->pppoe_pa.remote);
146 struct pppox_sock *ret;
147
148 ret = item_hash_table[hash];
149 while (ret) {
150 if (cmp_2_addr(&ret->pppoe_pa, &po->pppoe_pa))
151 return -EALREADY;
152
153 ret = ret->next;
154 }
155
156 if (!ret) {
157 po->next = item_hash_table[hash];
158 item_hash_table[hash] = po;
159 }
160
161 return 0;
162}
163
164static struct pppox_sock *__delete_item(unsigned long sid, char *addr)
165{
166 int hash = hash_item(sid, addr);
167 struct pppox_sock *ret, **src;
168
169 ret = item_hash_table[hash];
170 src = &item_hash_table[hash];
171
172 while (ret) {
173 if (cmp_addr(&ret->pppoe_pa, sid, addr)) {
174 *src = ret->next;
175 break;
176 }
177
178 src = &ret->next;
179 ret = ret->next;
180 }
181
182 return ret;
183}
184
185/**********************************************************************
186 *
187 * Set/get/delete/rehash items
188 *
189 **********************************************************************/
190static inline struct pppox_sock *get_item(unsigned long sid,
191 unsigned char *addr)
192{
193 struct pppox_sock *po;
194
195 read_lock_bh(&pppoe_hash_lock);
196 po = __get_item(sid, addr);
197 if (po)
198 sock_hold(sk_pppox(po));
199 read_unlock_bh(&pppoe_hash_lock);
200
201 return po;
202}
203
204static inline struct pppox_sock *get_item_by_addr(struct sockaddr_pppox *sp)
205{
206 return get_item(sp->sa_addr.pppoe.sid, sp->sa_addr.pppoe.remote);
207}
208
209static inline int set_item(struct pppox_sock *po)
210{
211 int i;
212
213 if (!po)
214 return -EINVAL;
215
216 write_lock_bh(&pppoe_hash_lock);
217 i = __set_item(po);
218 write_unlock_bh(&pppoe_hash_lock);
219
220 return i;
221}
222
223static inline struct pppox_sock *delete_item(unsigned long sid, char *addr)
224{
225 struct pppox_sock *ret;
226
227 write_lock_bh(&pppoe_hash_lock);
228 ret = __delete_item(sid, addr);
229 write_unlock_bh(&pppoe_hash_lock);
230
231 return ret;
232}
233
234
235
236/***************************************************************************
237 *
238 * Handler for device events.
239 * Certain device events require that sockets be unconnected.
240 *
241 **************************************************************************/
242
243static void pppoe_flush_dev(struct net_device *dev)
244{
245 int hash;
246
247 BUG_ON(dev == NULL);
248
249 read_lock_bh(&pppoe_hash_lock);
250 for (hash = 0; hash < PPPOE_HASH_SIZE; hash++) {
251 struct pppox_sock *po = item_hash_table[hash];
252
253 while (po != NULL) {
254 if (po->pppoe_dev == dev) {
255 struct sock *sk = sk_pppox(po);
256
257 sock_hold(sk);
258 po->pppoe_dev = NULL;
259
260 /* We hold a reference to SK, now drop the
261 * hash table lock so that we may attempt
262 * to lock the socket (which can sleep).
263 */
264 read_unlock_bh(&pppoe_hash_lock);
265
266 lock_sock(sk);
267
268 if (sk->sk_state &
269 (PPPOX_CONNECTED | PPPOX_BOUND)) {
270 pppox_unbind_sock(sk);
271 dev_put(dev);
272 sk->sk_state = PPPOX_ZOMBIE;
273 sk->sk_state_change(sk);
274 }
275
276 release_sock(sk);
277
278 sock_put(sk);
279
280 read_lock_bh(&pppoe_hash_lock);
281
282 /* Now restart from the beginning of this
283 * hash chain. We always NULL out pppoe_dev
284 * so we are guaranteed to make forward
285 * progress.
286 */
287 po = item_hash_table[hash];
288 continue;
289 }
290 po = po->next;
291 }
292 }
293 read_unlock_bh(&pppoe_hash_lock);
294}
295
296static int pppoe_device_event(struct notifier_block *this,
297 unsigned long event, void *ptr)
298{
299 struct net_device *dev = (struct net_device *) ptr;
300
301 /* Only look at sockets that are using this specific device. */
302 switch (event) {
303 case NETDEV_CHANGEMTU:
304 /* A change in mtu is a bad thing, requiring
305 * LCP re-negotiation.
306 */
307
308 case NETDEV_GOING_DOWN:
309 case NETDEV_DOWN:
310 /* Find every socket on this device and kill it. */
311 pppoe_flush_dev(dev);
312 break;
313
314 default:
315 break;
316 };
317
318 return NOTIFY_DONE;
319}
320
321
322static struct notifier_block pppoe_notifier = {
323 .notifier_call = pppoe_device_event,
324};
325
326
327/************************************************************************
328 *
329 * Do the real work of receiving a PPPoE Session frame.
330 *
331 ***********************************************************************/
332static int pppoe_rcv_core(struct sock *sk, struct sk_buff *skb)
333{
334 struct pppox_sock *po = pppox_sk(sk);
335 struct pppox_sock *relay_po = NULL;
336
337 if (sk->sk_state & PPPOX_BOUND) {
338 struct pppoe_hdr *ph = (struct pppoe_hdr *) skb->nh.raw;
339 int len = ntohs(ph->length);
340 skb_pull(skb, sizeof(struct pppoe_hdr));
341 skb_postpull_rcsum(skb, ph, sizeof(*ph));
342 if (pskb_trim_rcsum(skb, len))
343 goto abort_kfree;
344
345 ppp_input(&po->chan, skb);
346 } else if (sk->sk_state & PPPOX_RELAY) {
347 relay_po = get_item_by_addr(&po->pppoe_relay);
348
349 if (relay_po == NULL)
350 goto abort_kfree;
351
352 if ((sk_pppox(relay_po)->sk_state & PPPOX_CONNECTED) == 0)
353 goto abort_put;
354
355 skb_pull(skb, sizeof(struct pppoe_hdr));
356 if (!__pppoe_xmit(sk_pppox(relay_po), skb))
357 goto abort_put;
358 } else {
359 if (sock_queue_rcv_skb(sk, skb))
360 goto abort_kfree;
361 }
362
363 return NET_RX_SUCCESS;
364
365abort_put:
366 sock_put(sk_pppox(relay_po));
367
368abort_kfree:
369 kfree_skb(skb);
370 return NET_RX_DROP;
371}
372
373/************************************************************************
374 *
375 * Receive wrapper called in BH context.
376 *
377 ***********************************************************************/
378static int pppoe_rcv(struct sk_buff *skb,
379 struct net_device *dev,
380 struct packet_type *pt)
381
382{
383 struct pppoe_hdr *ph;
384 struct pppox_sock *po;
385 struct sock *sk;
386 int ret;
387
388 if (!pskb_may_pull(skb, sizeof(struct pppoe_hdr)))
389 goto drop;
390
391 if (!(skb = skb_share_check(skb, GFP_ATOMIC)))
392 goto out;
393
394 ph = (struct pppoe_hdr *) skb->nh.raw;
395
396 po = get_item((unsigned long) ph->sid, eth_hdr(skb)->h_source);
397 if (!po)
398 goto drop;
399
400 sk = sk_pppox(po);
401 bh_lock_sock(sk);
402
403 /* Socket state is unknown, must put skb into backlog. */
404 if (sock_owned_by_user(sk) != 0) {
405 sk_add_backlog(sk, skb);
406 ret = NET_RX_SUCCESS;
407 } else {
408 ret = pppoe_rcv_core(sk, skb);
409 }
410
411 bh_unlock_sock(sk);
412 sock_put(sk);
413
414 return ret;
415drop:
416 kfree_skb(skb);
417out:
418 return NET_RX_DROP;
419}
420
421/************************************************************************
422 *
423 * Receive a PPPoE Discovery frame.
424 * This is solely for detection of PADT frames
425 *
426 ***********************************************************************/
427static int pppoe_disc_rcv(struct sk_buff *skb,
428 struct net_device *dev,
429 struct packet_type *pt)
430
431{
432 struct pppoe_hdr *ph;
433 struct pppox_sock *po;
434
435 if (!pskb_may_pull(skb, sizeof(struct pppoe_hdr)))
436 goto abort;
437
438 if (!(skb = skb_share_check(skb, GFP_ATOMIC)))
439 goto out;
440
441 ph = (struct pppoe_hdr *) skb->nh.raw;
442 if (ph->code != PADT_CODE)
443 goto abort;
444
445 po = get_item((unsigned long) ph->sid, eth_hdr(skb)->h_source);
446 if (po) {
447 struct sock *sk = sk_pppox(po);
448
449 bh_lock_sock(sk);
450
451 /* If the user has locked the socket, just ignore
452 * the packet. With the way two rcv protocols hook into
453 * one socket family type, we cannot (easily) distinguish
454 * what kind of SKB it is during backlog rcv.
455 */
456 if (sock_owned_by_user(sk) == 0) {
457 /* We're no longer connect at the PPPOE layer,
458 * and must wait for ppp channel to disconnect us.
459 */
460 sk->sk_state = PPPOX_ZOMBIE;
461 }
462
463 bh_unlock_sock(sk);
464 sock_put(sk);
465 }
466
467abort:
468 kfree_skb(skb);
469out:
470 return NET_RX_SUCCESS; /* Lies... :-) */
471}
472
473static struct packet_type pppoes_ptype = {
474 .type = __constant_htons(ETH_P_PPP_SES),
475 .func = pppoe_rcv,
476};
477
478static struct packet_type pppoed_ptype = {
479 .type = __constant_htons(ETH_P_PPP_DISC),
480 .func = pppoe_disc_rcv,
481};
482
483static struct proto pppoe_sk_proto = {
484 .name = "PPPOE",
485 .owner = THIS_MODULE,
486 .obj_size = sizeof(struct pppox_sock),
487};
488
489/***********************************************************************
490 *
491 * Initialize a new struct sock.
492 *
493 **********************************************************************/
494static int pppoe_create(struct socket *sock)
495{
496 int error = -ENOMEM;
497 struct sock *sk;
498
499 sk = sk_alloc(PF_PPPOX, GFP_KERNEL, &pppoe_sk_proto, 1);
500 if (!sk)
501 goto out;
502
503 sock_init_data(sock, sk);
504
505 sock->state = SS_UNCONNECTED;
506 sock->ops = &pppoe_ops;
507
508 sk->sk_backlog_rcv = pppoe_rcv_core;
509 sk->sk_state = PPPOX_NONE;
510 sk->sk_type = SOCK_STREAM;
511 sk->sk_family = PF_PPPOX;
512 sk->sk_protocol = PX_PROTO_OE;
513
514 error = 0;
515out: return error;
516}
517
518static int pppoe_release(struct socket *sock)
519{
520 struct sock *sk = sock->sk;
521 struct pppox_sock *po;
522 int error = 0;
523
524 if (!sk)
525 return 0;
526
527 if (sock_flag(sk, SOCK_DEAD))
528 return -EBADF;
529
530 pppox_unbind_sock(sk);
531
532 /* Signal the death of the socket. */
533 sk->sk_state = PPPOX_DEAD;
534
535 po = pppox_sk(sk);
536 if (po->pppoe_pa.sid) {
537 delete_item(po->pppoe_pa.sid, po->pppoe_pa.remote);
538 }
539
540 if (po->pppoe_dev)
541 dev_put(po->pppoe_dev);
542
543 po->pppoe_dev = NULL;
544
545 sock_orphan(sk);
546 sock->sk = NULL;
547
548 skb_queue_purge(&sk->sk_receive_queue);
549 sock_put(sk);
550
551 return error;
552}
553
554
555static int pppoe_connect(struct socket *sock, struct sockaddr *uservaddr,
556 int sockaddr_len, int flags)
557{
558 struct sock *sk = sock->sk;
559 struct net_device *dev = NULL;
560 struct sockaddr_pppox *sp = (struct sockaddr_pppox *) uservaddr;
561 struct pppox_sock *po = pppox_sk(sk);
562 int error;
563
564 lock_sock(sk);
565
566 error = -EINVAL;
567 if (sp->sa_protocol != PX_PROTO_OE)
568 goto end;
569
570 /* Check for already bound sockets */
571 error = -EBUSY;
572 if ((sk->sk_state & PPPOX_CONNECTED) && sp->sa_addr.pppoe.sid)
573 goto end;
574
575 /* Check for already disconnected sockets, on attempts to disconnect */
576 error = -EALREADY;
577 if ((sk->sk_state & PPPOX_DEAD) && !sp->sa_addr.pppoe.sid )
578 goto end;
579
580 error = 0;
581 if (po->pppoe_pa.sid) {
582 pppox_unbind_sock(sk);
583
584 /* Delete the old binding */
585 delete_item(po->pppoe_pa.sid,po->pppoe_pa.remote);
586
587 if(po->pppoe_dev)
588 dev_put(po->pppoe_dev);
589
590 memset(sk_pppox(po) + 1, 0,
591 sizeof(struct pppox_sock) - sizeof(struct sock));
592
593 sk->sk_state = PPPOX_NONE;
594 }
595
596 /* Don't re-bind if sid==0 */
597 if (sp->sa_addr.pppoe.sid != 0) {
598 dev = dev_get_by_name(sp->sa_addr.pppoe.dev);
599
600 error = -ENODEV;
601 if (!dev)
602 goto end;
603
604 po->pppoe_dev = dev;
605
606 if (!(dev->flags & IFF_UP))
607 goto err_put;
608
609 memcpy(&po->pppoe_pa,
610 &sp->sa_addr.pppoe,
611 sizeof(struct pppoe_addr));
612
613 error = set_item(po);
614 if (error < 0)
615 goto err_put;
616
617 po->chan.hdrlen = (sizeof(struct pppoe_hdr) +
618 dev->hard_header_len);
619
620 po->chan.private = sk;
621 po->chan.ops = &pppoe_chan_ops;
622
623 error = ppp_register_channel(&po->chan);
624 if (error)
625 goto err_put;
626
627 sk->sk_state = PPPOX_CONNECTED;
628 }
629
630 po->num = sp->sa_addr.pppoe.sid;
631
632 end:
633 release_sock(sk);
634 return error;
635err_put:
636 if (po->pppoe_dev) {
637 dev_put(po->pppoe_dev);
638 po->pppoe_dev = NULL;
639 }
640 goto end;
641}
642
643
644static int pppoe_getname(struct socket *sock, struct sockaddr *uaddr,
645 int *usockaddr_len, int peer)
646{
647 int len = sizeof(struct sockaddr_pppox);
648 struct sockaddr_pppox sp;
649
650 sp.sa_family = AF_PPPOX;
651 sp.sa_protocol = PX_PROTO_OE;
652 memcpy(&sp.sa_addr.pppoe, &pppox_sk(sock->sk)->pppoe_pa,
653 sizeof(struct pppoe_addr));
654
655 memcpy(uaddr, &sp, len);
656
657 *usockaddr_len = len;
658
659 return 0;
660}
661
662
663static int pppoe_ioctl(struct socket *sock, unsigned int cmd,
664 unsigned long arg)
665{
666 struct sock *sk = sock->sk;
667 struct pppox_sock *po = pppox_sk(sk);
668 int val = 0;
669 int err = 0;
670
671 switch (cmd) {
672 case PPPIOCGMRU:
673 err = -ENXIO;
674
675 if (!(sk->sk_state & PPPOX_CONNECTED))
676 break;
677
678 err = -EFAULT;
679 if (put_user(po->pppoe_dev->mtu -
680 sizeof(struct pppoe_hdr) -
681 PPP_HDRLEN,
682 (int __user *) arg))
683 break;
684 err = 0;
685 break;
686
687 case PPPIOCSMRU:
688 err = -ENXIO;
689 if (!(sk->sk_state & PPPOX_CONNECTED))
690 break;
691
692 err = -EFAULT;
693 if (get_user(val,(int __user *) arg))
694 break;
695
696 if (val < (po->pppoe_dev->mtu
697 - sizeof(struct pppoe_hdr)
698 - PPP_HDRLEN))
699 err = 0;
700 else
701 err = -EINVAL;
702 break;
703
704 case PPPIOCSFLAGS:
705 err = -EFAULT;
706 if (get_user(val, (int __user *) arg))
707 break;
708 err = 0;
709 break;
710
711 case PPPOEIOCSFWD:
712 {
713 struct pppox_sock *relay_po;
714
715 err = -EBUSY;
716 if (sk->sk_state & (PPPOX_BOUND | PPPOX_ZOMBIE | PPPOX_DEAD))
717 break;
718
719 err = -ENOTCONN;
720 if (!(sk->sk_state & PPPOX_CONNECTED))
721 break;
722
723 /* PPPoE address from the user specifies an outbound
724 PPPoE address to which frames are forwarded to */
725 err = -EFAULT;
726 if (copy_from_user(&po->pppoe_relay,
727 (void __user *)arg,
728 sizeof(struct sockaddr_pppox)))
729 break;
730
731 err = -EINVAL;
732 if (po->pppoe_relay.sa_family != AF_PPPOX ||
733 po->pppoe_relay.sa_protocol!= PX_PROTO_OE)
734 break;
735
736 /* Check that the socket referenced by the address
737 actually exists. */
738 relay_po = get_item_by_addr(&po->pppoe_relay);
739
740 if (!relay_po)
741 break;
742
743 sock_put(sk_pppox(relay_po));
744 sk->sk_state |= PPPOX_RELAY;
745 err = 0;
746 break;
747 }
748
749 case PPPOEIOCDFWD:
750 err = -EALREADY;
751 if (!(sk->sk_state & PPPOX_RELAY))
752 break;
753
754 sk->sk_state &= ~PPPOX_RELAY;
755 err = 0;
756 break;
757
758 default:;
759 };
760
761 return err;
762}
763
764
765static int pppoe_sendmsg(struct kiocb *iocb, struct socket *sock,
766 struct msghdr *m, size_t total_len)
767{
768 struct sk_buff *skb = NULL;
769 struct sock *sk = sock->sk;
770 struct pppox_sock *po = pppox_sk(sk);
771 int error = 0;
772 struct pppoe_hdr hdr;
773 struct pppoe_hdr *ph;
774 struct net_device *dev;
775 char *start;
776
777 if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED)) {
778 error = -ENOTCONN;
779 goto end;
780 }
781
782 hdr.ver = 1;
783 hdr.type = 1;
784 hdr.code = 0;
785 hdr.sid = po->num;
786
787 lock_sock(sk);
788
789 dev = po->pppoe_dev;
790
791 error = -EMSGSIZE;
792 if (total_len > (dev->mtu + dev->hard_header_len))
793 goto end;
794
795
796 skb = sock_wmalloc(sk, total_len + dev->hard_header_len + 32,
797 0, GFP_KERNEL);
798 if (!skb) {
799 error = -ENOMEM;
800 goto end;
801 }
802
803 /* Reserve space for headers. */
804 skb_reserve(skb, dev->hard_header_len);
805 skb->nh.raw = skb->data;
806
807 skb->dev = dev;
808
809 skb->priority = sk->sk_priority;
810 skb->protocol = __constant_htons(ETH_P_PPP_SES);
811
812 ph = (struct pppoe_hdr *) skb_put(skb, total_len + sizeof(struct pppoe_hdr));
813 start = (char *) &ph->tag[0];
814
815 error = memcpy_fromiovec(start, m->msg_iov, total_len);
816
817 if (error < 0) {
818 kfree_skb(skb);
819 goto end;
820 }
821
822 error = total_len;
823 dev->hard_header(skb, dev, ETH_P_PPP_SES,
824 po->pppoe_pa.remote, NULL, total_len);
825
826 memcpy(ph, &hdr, sizeof(struct pppoe_hdr));
827
828 ph->length = htons(total_len);
829
830 dev_queue_xmit(skb);
831
832end:
833 release_sock(sk);
834 return error;
835}
836
837
838/************************************************************************
839 *
840 * xmit function for internal use.
841 *
842 ***********************************************************************/
843static int __pppoe_xmit(struct sock *sk, struct sk_buff *skb)
844{
845 struct pppox_sock *po = pppox_sk(sk);
846 struct net_device *dev = po->pppoe_dev;
847 struct pppoe_hdr hdr;
848 struct pppoe_hdr *ph;
849 int headroom = skb_headroom(skb);
850 int data_len = skb->len;
851 struct sk_buff *skb2;
852
853 if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED))
854 goto abort;
855
856 hdr.ver = 1;
857 hdr.type = 1;
858 hdr.code = 0;
859 hdr.sid = po->num;
860 hdr.length = htons(skb->len);
861
862 if (!dev)
863 goto abort;
864
865 /* Copy the skb if there is no space for the header. */
866 if (headroom < (sizeof(struct pppoe_hdr) + dev->hard_header_len)) {
867 skb2 = dev_alloc_skb(32+skb->len +
868 sizeof(struct pppoe_hdr) +
869 dev->hard_header_len);
870
871 if (skb2 == NULL)
872 goto abort;
873
874 skb_reserve(skb2, dev->hard_header_len + sizeof(struct pppoe_hdr));
875 memcpy(skb_put(skb2, skb->len), skb->data, skb->len);
876 } else {
877 /* Make a clone so as to not disturb the original skb,
878 * give dev_queue_xmit something it can free.
879 */
880 skb2 = skb_clone(skb, GFP_ATOMIC);
881 }
882
883 ph = (struct pppoe_hdr *) skb_push(skb2, sizeof(struct pppoe_hdr));
884 memcpy(ph, &hdr, sizeof(struct pppoe_hdr));
885 skb2->protocol = __constant_htons(ETH_P_PPP_SES);
886
887 skb2->nh.raw = skb2->data;
888
889 skb2->dev = dev;
890
891 dev->hard_header(skb2, dev, ETH_P_PPP_SES,
892 po->pppoe_pa.remote, NULL, data_len);
893
894 /* We're transmitting skb2, and assuming that dev_queue_xmit
895 * will free it. The generic ppp layer however, is expecting
896 * that we give back 'skb' (not 'skb2') in case of failure,
897 * but free it in case of success.
898 */
899
900 if (dev_queue_xmit(skb2) < 0)
901 goto abort;
902
903 kfree_skb(skb);
904 return 1;
905
906abort:
907 return 0;
908}
909
910
911/************************************************************************
912 *
913 * xmit function called by generic PPP driver
914 * sends PPP frame over PPPoE socket
915 *
916 ***********************************************************************/
917static int pppoe_xmit(struct ppp_channel *chan, struct sk_buff *skb)
918{
919 struct sock *sk = (struct sock *) chan->private;
920 return __pppoe_xmit(sk, skb);
921}
922
923
924static struct ppp_channel_ops pppoe_chan_ops = {
925 .start_xmit = pppoe_xmit,
926};
927
928static int pppoe_recvmsg(struct kiocb *iocb, struct socket *sock,
929 struct msghdr *m, size_t total_len, int flags)
930{
931 struct sock *sk = sock->sk;
932 struct sk_buff *skb = NULL;
933 int error = 0;
934 int len;
935 struct pppoe_hdr *ph = NULL;
936
937 if (sk->sk_state & PPPOX_BOUND) {
938 error = -EIO;
939 goto end;
940 }
941
942 skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
943 flags & MSG_DONTWAIT, &error);
944
945 if (error < 0) {
946 goto end;
947 }
948
949 m->msg_namelen = 0;
950
951 if (skb) {
952 error = 0;
953 ph = (struct pppoe_hdr *) skb->nh.raw;
954 len = ntohs(ph->length);
955
956 error = memcpy_toiovec(m->msg_iov, (unsigned char *) &ph->tag[0], len);
957 if (error < 0)
958 goto do_skb_free;
959 error = len;
960 }
961
962do_skb_free:
963 if (skb)
964 kfree_skb(skb);
965end:
966 return error;
967}
968
969#ifdef CONFIG_PROC_FS
970static int pppoe_seq_show(struct seq_file *seq, void *v)
971{
972 struct pppox_sock *po;
973 char *dev_name;
974
975 if (v == SEQ_START_TOKEN) {
976 seq_puts(seq, "Id Address Device\n");
977 goto out;
978 }
979
980 po = v;
981 dev_name = po->pppoe_pa.dev;
982
983 seq_printf(seq, "%08X %02X:%02X:%02X:%02X:%02X:%02X %8s\n",
984 po->pppoe_pa.sid,
985 po->pppoe_pa.remote[0], po->pppoe_pa.remote[1],
986 po->pppoe_pa.remote[2], po->pppoe_pa.remote[3],
987 po->pppoe_pa.remote[4], po->pppoe_pa.remote[5], dev_name);
988out:
989 return 0;
990}
991
992static __inline__ struct pppox_sock *pppoe_get_idx(loff_t pos)
993{
994 struct pppox_sock *po = NULL;
995 int i = 0;
996
997 for (; i < PPPOE_HASH_SIZE; i++) {
998 po = item_hash_table[i];
999 while (po) {
1000 if (!pos--)
1001 goto out;
1002 po = po->next;
1003 }
1004 }
1005out:
1006 return po;
1007}
1008
1009static void *pppoe_seq_start(struct seq_file *seq, loff_t *pos)
1010{
1011 loff_t l = *pos;
1012
1013 read_lock_bh(&pppoe_hash_lock);
1014 return l ? pppoe_get_idx(--l) : SEQ_START_TOKEN;
1015}
1016
1017static void *pppoe_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1018{
1019 struct pppox_sock *po;
1020
1021 ++*pos;
1022 if (v == SEQ_START_TOKEN) {
1023 po = pppoe_get_idx(0);
1024 goto out;
1025 }
1026 po = v;
1027 if (po->next)
1028 po = po->next;
1029 else {
1030 int hash = hash_item(po->pppoe_pa.sid, po->pppoe_pa.remote);
1031
1032 while (++hash < PPPOE_HASH_SIZE) {
1033 po = item_hash_table[hash];
1034 if (po)
1035 break;
1036 }
1037 }
1038out:
1039 return po;
1040}
1041
1042static void pppoe_seq_stop(struct seq_file *seq, void *v)
1043{
1044 read_unlock_bh(&pppoe_hash_lock);
1045}
1046
1047static struct seq_operations pppoe_seq_ops = {
1048 .start = pppoe_seq_start,
1049 .next = pppoe_seq_next,
1050 .stop = pppoe_seq_stop,
1051 .show = pppoe_seq_show,
1052};
1053
1054static int pppoe_seq_open(struct inode *inode, struct file *file)
1055{
1056 return seq_open(file, &pppoe_seq_ops);
1057}
1058
1059static struct file_operations pppoe_seq_fops = {
1060 .owner = THIS_MODULE,
1061 .open = pppoe_seq_open,
1062 .read = seq_read,
1063 .llseek = seq_lseek,
1064 .release = seq_release,
1065};
1066
1067static int __init pppoe_proc_init(void)
1068{
1069 struct proc_dir_entry *p;
1070
1071 p = create_proc_entry("pppoe", S_IRUGO, proc_net);
1072 if (!p)
1073 return -ENOMEM;
1074
1075 p->proc_fops = &pppoe_seq_fops;
1076 return 0;
1077}
1078#else /* CONFIG_PROC_FS */
1079static inline int pppoe_proc_init(void) { return 0; }
1080#endif /* CONFIG_PROC_FS */
1081
1082/* ->ioctl are set at pppox_create */
1083
1084static struct proto_ops pppoe_ops = {
1085 .family = AF_PPPOX,
1086 .owner = THIS_MODULE,
1087 .release = pppoe_release,
1088 .bind = sock_no_bind,
1089 .connect = pppoe_connect,
1090 .socketpair = sock_no_socketpair,
1091 .accept = sock_no_accept,
1092 .getname = pppoe_getname,
1093 .poll = datagram_poll,
1094 .listen = sock_no_listen,
1095 .shutdown = sock_no_shutdown,
1096 .setsockopt = sock_no_setsockopt,
1097 .getsockopt = sock_no_getsockopt,
1098 .sendmsg = pppoe_sendmsg,
1099 .recvmsg = pppoe_recvmsg,
1100 .mmap = sock_no_mmap
1101};
1102
1103static struct pppox_proto pppoe_proto = {
1104 .create = pppoe_create,
1105 .ioctl = pppoe_ioctl,
1106 .owner = THIS_MODULE,
1107};
1108
1109
1110static int __init pppoe_init(void)
1111{
1112 int err = proto_register(&pppoe_sk_proto, 0);
1113
1114 if (err)
1115 goto out;
1116
1117 err = register_pppox_proto(PX_PROTO_OE, &pppoe_proto);
1118 if (err)
1119 goto out_unregister_pppoe_proto;
1120
1121 err = pppoe_proc_init();
1122 if (err)
1123 goto out_unregister_pppox_proto;
1124
1125 dev_add_pack(&pppoes_ptype);
1126 dev_add_pack(&pppoed_ptype);
1127 register_netdevice_notifier(&pppoe_notifier);
1128out:
1129 return err;
1130out_unregister_pppox_proto:
1131 unregister_pppox_proto(PX_PROTO_OE);
1132out_unregister_pppoe_proto:
1133 proto_unregister(&pppoe_sk_proto);
1134 goto out;
1135}
1136
1137static void __exit pppoe_exit(void)
1138{
1139 unregister_pppox_proto(PX_PROTO_OE);
1140 dev_remove_pack(&pppoes_ptype);
1141 dev_remove_pack(&pppoed_ptype);
1142 unregister_netdevice_notifier(&pppoe_notifier);
1143 remove_proc_entry("pppoe", proc_net);
1144 proto_unregister(&pppoe_sk_proto);
1145}
1146
1147module_init(pppoe_init);
1148module_exit(pppoe_exit);
1149
1150MODULE_AUTHOR("Michal Ostrowski <mostrows@speakeasy.net>");
1151MODULE_DESCRIPTION("PPP over Ethernet driver");
1152MODULE_LICENSE("GPL");
1153MODULE_ALIAS_NETPROTO(PF_PPPOX);