proc: use seq_puts()/seq_putc() where possible
[linux-2.6/next.git] / drivers / net / pppoe.c
blob78c0e3c9b2b5fcb8d42fb910ab2416e4db787dc7
1 /** -*- linux-c -*- ***********************************************************
2 * Linux PPP over Ethernet (PPPoX/PPPoE) Sockets
4 * PPPoX --- Generic PPP encapsulation socket family
5 * PPPoE --- PPP over Ethernet (RFC 2516)
8 * Version: 0.7.0
10 * 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 ...)
16 * 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)
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.
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>
75 #include <linux/if_ppp.h>
76 #include <linux/notifier.h>
77 #include <linux/file.h>
78 #include <linux/proc_fs.h>
79 #include <linux/seq_file.h>
81 #include <linux/nsproxy.h>
82 #include <net/net_namespace.h>
83 #include <net/netns/generic.h>
84 #include <net/sock.h>
86 #include <asm/uaccess.h>
88 #define PPPOE_HASH_BITS 4
89 #define PPPOE_HASH_SIZE (1 << PPPOE_HASH_BITS)
90 #define PPPOE_HASH_MASK (PPPOE_HASH_SIZE - 1)
92 static int __pppoe_xmit(struct sock *sk, struct sk_buff *skb);
94 static const struct proto_ops pppoe_ops;
95 static const struct ppp_channel_ops pppoe_chan_ops;
97 /* per-net private data for this module */
98 static int pppoe_net_id __read_mostly;
99 struct pppoe_net {
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
108 struct pppox_sock *hash_table[PPPOE_HASH_SIZE];
109 rwlock_t hash_lock;
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)
117 * Ethernet frames have a special tag for this but
118 * we use simplier approach based on session id
120 static inline bool stage_session(__be16 sid)
122 return sid != 0;
125 static inline struct pppoe_net *pppoe_pernet(struct net *net)
127 BUG_ON(!net);
129 return net_generic(net, pppoe_net_id);
132 static inline int cmp_2_addr(struct pppoe_addr *a, struct pppoe_addr *b)
134 return a->sid == b->sid && !memcmp(a->remote, b->remote, ETH_ALEN);
137 static inline int cmp_addr(struct pppoe_addr *a, __be16 sid, char *addr)
139 return a->sid == sid && !memcmp(a->remote, addr, ETH_ALEN);
142 #if 8 % PPPOE_HASH_BITS
143 #error 8 must be a multiple of PPPOE_HASH_BITS
144 #endif
146 static int hash_item(__be16 sid, unsigned char *addr)
148 unsigned char hash = 0;
149 unsigned int i;
151 for (i = 0; i < ETH_ALEN; i++)
152 hash ^= addr[i];
153 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;
158 return hash & PPPOE_HASH_MASK;
161 /**********************************************************************
163 * Set/get/delete/rehash items (internal versions)
165 **********************************************************************/
166 static struct pppox_sock *__get_item(struct pppoe_net *pn, __be16 sid,
167 unsigned char *addr, int ifindex)
169 int hash = hash_item(sid, addr);
170 struct pppox_sock *ret;
172 ret = pn->hash_table[hash];
173 while (ret) {
174 if (cmp_addr(&ret->pppoe_pa, sid, addr) &&
175 ret->pppoe_ifindex == ifindex)
176 return ret;
178 ret = ret->next;
181 return NULL;
184 static int __set_item(struct pppoe_net *pn, struct pppox_sock *po)
186 int hash = hash_item(po->pppoe_pa.sid, po->pppoe_pa.remote);
187 struct pppox_sock *ret;
189 ret = pn->hash_table[hash];
190 while (ret) {
191 if (cmp_2_addr(&ret->pppoe_pa, &po->pppoe_pa) &&
192 ret->pppoe_ifindex == po->pppoe_ifindex)
193 return -EALREADY;
195 ret = ret->next;
198 po->next = pn->hash_table[hash];
199 pn->hash_table[hash] = po;
201 return 0;
204 static struct pppox_sock *__delete_item(struct pppoe_net *pn, __be16 sid,
205 char *addr, int ifindex)
207 int hash = hash_item(sid, addr);
208 struct pppox_sock *ret, **src;
210 ret = pn->hash_table[hash];
211 src = &pn->hash_table[hash];
213 while (ret) {
214 if (cmp_addr(&ret->pppoe_pa, sid, addr) &&
215 ret->pppoe_ifindex == ifindex) {
216 *src = ret->next;
217 break;
220 src = &ret->next;
221 ret = ret->next;
224 return ret;
227 /**********************************************************************
229 * Set/get/delete/rehash items
231 **********************************************************************/
232 static inline struct pppox_sock *get_item(struct pppoe_net *pn, __be16 sid,
233 unsigned char *addr, int ifindex)
235 struct pppox_sock *po;
237 read_lock_bh(&pn->hash_lock);
238 po = __get_item(pn, sid, addr, ifindex);
239 if (po)
240 sock_hold(sk_pppox(po));
241 read_unlock_bh(&pn->hash_lock);
243 return po;
246 static inline struct pppox_sock *get_item_by_addr(struct net *net,
247 struct sockaddr_pppox *sp)
249 struct net_device *dev;
250 struct pppoe_net *pn;
251 struct pppox_sock *pppox_sock = NULL;
253 int ifindex;
255 rcu_read_lock();
256 dev = dev_get_by_name_rcu(net, sp->sa_addr.pppoe.dev);
257 if (dev) {
258 ifindex = dev->ifindex;
259 pn = pppoe_pernet(net);
260 pppox_sock = get_item(pn, sp->sa_addr.pppoe.sid,
261 sp->sa_addr.pppoe.remote, ifindex);
263 rcu_read_unlock();
264 return pppox_sock;
267 static inline struct pppox_sock *delete_item(struct pppoe_net *pn, __be16 sid,
268 char *addr, int ifindex)
270 struct pppox_sock *ret;
272 write_lock_bh(&pn->hash_lock);
273 ret = __delete_item(pn, sid, addr, ifindex);
274 write_unlock_bh(&pn->hash_lock);
276 return ret;
279 /***************************************************************************
281 * Handler for device events.
282 * Certain device events require that sockets be unconnected.
284 **************************************************************************/
286 static void pppoe_flush_dev(struct net_device *dev)
288 struct pppoe_net *pn;
289 int i;
291 pn = pppoe_pernet(dev_net(dev));
292 write_lock_bh(&pn->hash_lock);
293 for (i = 0; i < PPPOE_HASH_SIZE; i++) {
294 struct pppox_sock *po = pn->hash_table[i];
295 struct sock *sk;
297 while (po) {
298 while (po && po->pppoe_dev != dev) {
299 po = po->next;
302 if (!po)
303 break;
305 sk = sk_pppox(po);
307 /* We always grab the socket lock, followed by the
308 * hash_lock, in that order. Since we should hold the
309 * sock lock while doing any unbinding, we need to
310 * release the lock we're holding. Hold a reference to
311 * the sock so it doesn't disappear as we're jumping
312 * between locks.
315 sock_hold(sk);
316 write_unlock_bh(&pn->hash_lock);
317 lock_sock(sk);
319 if (po->pppoe_dev == dev &&
320 sk->sk_state & (PPPOX_CONNECTED | PPPOX_BOUND)) {
321 pppox_unbind_sock(sk);
322 sk->sk_state = PPPOX_ZOMBIE;
323 sk->sk_state_change(sk);
324 po->pppoe_dev = NULL;
325 dev_put(dev);
328 release_sock(sk);
329 sock_put(sk);
331 /* Restart the process from the start of the current
332 * hash chain. We dropped locks so the world may have
333 * change from underneath us.
336 BUG_ON(pppoe_pernet(dev_net(dev)) == NULL);
337 write_lock_bh(&pn->hash_lock);
338 po = pn->hash_table[i];
341 write_unlock_bh(&pn->hash_lock);
344 static int pppoe_device_event(struct notifier_block *this,
345 unsigned long event, void *ptr)
347 struct net_device *dev = (struct net_device *)ptr;
349 /* Only look at sockets that are using this specific device. */
350 switch (event) {
351 case NETDEV_CHANGEMTU:
352 /* A change in mtu is a bad thing, requiring
353 * LCP re-negotiation.
356 case NETDEV_GOING_DOWN:
357 case NETDEV_DOWN:
358 /* Find every socket on this device and kill it. */
359 pppoe_flush_dev(dev);
360 break;
362 default:
363 break;
366 return NOTIFY_DONE;
369 static struct notifier_block pppoe_notifier = {
370 .notifier_call = pppoe_device_event,
373 /************************************************************************
375 * Do the real work of receiving a PPPoE Session frame.
377 ***********************************************************************/
378 static int pppoe_rcv_core(struct sock *sk, struct sk_buff *skb)
380 struct pppox_sock *po = pppox_sk(sk);
381 struct pppox_sock *relay_po;
383 /* Backlog receive. Semantics of backlog rcv preclude any code from
384 * executing in lock_sock()/release_sock() bounds; meaning sk->sk_state
385 * can't change.
388 if (sk->sk_state & PPPOX_BOUND) {
389 ppp_input(&po->chan, skb);
390 } else if (sk->sk_state & PPPOX_RELAY) {
391 relay_po = get_item_by_addr(sock_net(sk),
392 &po->pppoe_relay);
393 if (relay_po == NULL)
394 goto abort_kfree;
396 if ((sk_pppox(relay_po)->sk_state & PPPOX_CONNECTED) == 0)
397 goto abort_put;
399 if (!__pppoe_xmit(sk_pppox(relay_po), skb))
400 goto abort_put;
401 } else {
402 if (sock_queue_rcv_skb(sk, skb))
403 goto abort_kfree;
406 return NET_RX_SUCCESS;
408 abort_put:
409 sock_put(sk_pppox(relay_po));
411 abort_kfree:
412 kfree_skb(skb);
413 return NET_RX_DROP;
416 /************************************************************************
418 * Receive wrapper called in BH context.
420 ***********************************************************************/
421 static int pppoe_rcv(struct sk_buff *skb, struct net_device *dev,
422 struct packet_type *pt, struct net_device *orig_dev)
424 struct pppoe_hdr *ph;
425 struct pppox_sock *po;
426 struct pppoe_net *pn;
427 int len;
429 skb = skb_share_check(skb, GFP_ATOMIC);
430 if (!skb)
431 goto out;
433 if (!pskb_may_pull(skb, sizeof(struct pppoe_hdr)))
434 goto drop;
436 ph = pppoe_hdr(skb);
437 len = ntohs(ph->length);
439 skb_pull_rcsum(skb, sizeof(*ph));
440 if (skb->len < len)
441 goto drop;
443 if (pskb_trim_rcsum(skb, len))
444 goto drop;
446 pn = pppoe_pernet(dev_net(dev));
448 /* Note that get_item does a sock_hold(), so sk_pppox(po)
449 * is known to be safe.
451 po = get_item(pn, ph->sid, eth_hdr(skb)->h_source, dev->ifindex);
452 if (!po)
453 goto drop;
455 return sk_receive_skb(sk_pppox(po), skb, 0);
457 drop:
458 kfree_skb(skb);
459 out:
460 return NET_RX_DROP;
463 /************************************************************************
465 * Receive a PPPoE Discovery frame.
466 * This is solely for detection of PADT frames
468 ***********************************************************************/
469 static int pppoe_disc_rcv(struct sk_buff *skb, struct net_device *dev,
470 struct packet_type *pt, struct net_device *orig_dev)
473 struct pppoe_hdr *ph;
474 struct pppox_sock *po;
475 struct pppoe_net *pn;
477 skb = skb_share_check(skb, GFP_ATOMIC);
478 if (!skb)
479 goto out;
481 if (!pskb_may_pull(skb, sizeof(struct pppoe_hdr)))
482 goto abort;
484 ph = pppoe_hdr(skb);
485 if (ph->code != PADT_CODE)
486 goto abort;
488 pn = pppoe_pernet(dev_net(dev));
489 po = get_item(pn, ph->sid, eth_hdr(skb)->h_source, dev->ifindex);
490 if (po) {
491 struct sock *sk = sk_pppox(po);
493 bh_lock_sock(sk);
495 /* If the user has locked the socket, just ignore
496 * the packet. With the way two rcv protocols hook into
497 * one socket family type, we cannot (easily) distinguish
498 * what kind of SKB it is during backlog rcv.
500 if (sock_owned_by_user(sk) == 0) {
501 /* We're no longer connect at the PPPOE layer,
502 * and must wait for ppp channel to disconnect us.
504 sk->sk_state = PPPOX_ZOMBIE;
507 bh_unlock_sock(sk);
508 sock_put(sk);
511 abort:
512 kfree_skb(skb);
513 out:
514 return NET_RX_SUCCESS; /* Lies... :-) */
517 static struct packet_type pppoes_ptype __read_mostly = {
518 .type = cpu_to_be16(ETH_P_PPP_SES),
519 .func = pppoe_rcv,
522 static struct packet_type pppoed_ptype __read_mostly = {
523 .type = cpu_to_be16(ETH_P_PPP_DISC),
524 .func = pppoe_disc_rcv,
527 static struct proto pppoe_sk_proto __read_mostly = {
528 .name = "PPPOE",
529 .owner = THIS_MODULE,
530 .obj_size = sizeof(struct pppox_sock),
533 /***********************************************************************
535 * Initialize a new struct sock.
537 **********************************************************************/
538 static int pppoe_create(struct net *net, struct socket *sock)
540 struct sock *sk;
542 sk = sk_alloc(net, PF_PPPOX, GFP_KERNEL, &pppoe_sk_proto);
543 if (!sk)
544 return -ENOMEM;
546 sock_init_data(sock, sk);
548 sock->state = SS_UNCONNECTED;
549 sock->ops = &pppoe_ops;
551 sk->sk_backlog_rcv = pppoe_rcv_core;
552 sk->sk_state = PPPOX_NONE;
553 sk->sk_type = SOCK_STREAM;
554 sk->sk_family = PF_PPPOX;
555 sk->sk_protocol = PX_PROTO_OE;
557 return 0;
560 static int pppoe_release(struct socket *sock)
562 struct sock *sk = sock->sk;
563 struct pppox_sock *po;
564 struct pppoe_net *pn;
565 struct net *net = NULL;
567 if (!sk)
568 return 0;
570 lock_sock(sk);
571 if (sock_flag(sk, SOCK_DEAD)) {
572 release_sock(sk);
573 return -EBADF;
576 po = pppox_sk(sk);
578 if (sk->sk_state & (PPPOX_CONNECTED | PPPOX_BOUND)) {
579 dev_put(po->pppoe_dev);
580 po->pppoe_dev = NULL;
583 pppox_unbind_sock(sk);
585 /* Signal the death of the socket. */
586 sk->sk_state = PPPOX_DEAD;
588 net = sock_net(sk);
589 pn = pppoe_pernet(net);
592 * protect "po" from concurrent updates
593 * on pppoe_flush_dev
595 delete_item(pn, po->pppoe_pa.sid, po->pppoe_pa.remote,
596 po->pppoe_ifindex);
598 sock_orphan(sk);
599 sock->sk = NULL;
601 skb_queue_purge(&sk->sk_receive_queue);
602 release_sock(sk);
603 sock_put(sk);
605 return 0;
608 static int pppoe_connect(struct socket *sock, struct sockaddr *uservaddr,
609 int sockaddr_len, int flags)
611 struct sock *sk = sock->sk;
612 struct sockaddr_pppox *sp = (struct sockaddr_pppox *)uservaddr;
613 struct pppox_sock *po = pppox_sk(sk);
614 struct net_device *dev = NULL;
615 struct pppoe_net *pn;
616 struct net *net = NULL;
617 int error;
619 lock_sock(sk);
621 error = -EINVAL;
622 if (sp->sa_protocol != PX_PROTO_OE)
623 goto end;
625 /* Check for already bound sockets */
626 error = -EBUSY;
627 if ((sk->sk_state & PPPOX_CONNECTED) &&
628 stage_session(sp->sa_addr.pppoe.sid))
629 goto end;
631 /* Check for already disconnected sockets, on attempts to disconnect */
632 error = -EALREADY;
633 if ((sk->sk_state & PPPOX_DEAD) &&
634 !stage_session(sp->sa_addr.pppoe.sid))
635 goto end;
637 error = 0;
639 /* Delete the old binding */
640 if (stage_session(po->pppoe_pa.sid)) {
641 pppox_unbind_sock(sk);
642 pn = pppoe_pernet(sock_net(sk));
643 delete_item(pn, po->pppoe_pa.sid,
644 po->pppoe_pa.remote, po->pppoe_ifindex);
645 if (po->pppoe_dev) {
646 dev_put(po->pppoe_dev);
647 po->pppoe_dev = NULL;
650 memset(sk_pppox(po) + 1, 0,
651 sizeof(struct pppox_sock) - sizeof(struct sock));
652 sk->sk_state = PPPOX_NONE;
655 /* Re-bind in session stage only */
656 if (stage_session(sp->sa_addr.pppoe.sid)) {
657 error = -ENODEV;
658 net = sock_net(sk);
659 dev = dev_get_by_name(net, sp->sa_addr.pppoe.dev);
660 if (!dev)
661 goto err_put;
663 po->pppoe_dev = dev;
664 po->pppoe_ifindex = dev->ifindex;
665 pn = pppoe_pernet(net);
666 if (!(dev->flags & IFF_UP)) {
667 goto err_put;
670 memcpy(&po->pppoe_pa,
671 &sp->sa_addr.pppoe,
672 sizeof(struct pppoe_addr));
674 write_lock_bh(&pn->hash_lock);
675 error = __set_item(pn, po);
676 write_unlock_bh(&pn->hash_lock);
677 if (error < 0)
678 goto err_put;
680 po->chan.hdrlen = (sizeof(struct pppoe_hdr) +
681 dev->hard_header_len);
683 po->chan.mtu = dev->mtu - sizeof(struct pppoe_hdr);
684 po->chan.private = sk;
685 po->chan.ops = &pppoe_chan_ops;
687 error = ppp_register_net_channel(dev_net(dev), &po->chan);
688 if (error) {
689 delete_item(pn, po->pppoe_pa.sid,
690 po->pppoe_pa.remote, po->pppoe_ifindex);
691 goto err_put;
694 sk->sk_state = PPPOX_CONNECTED;
697 po->num = sp->sa_addr.pppoe.sid;
699 end:
700 release_sock(sk);
701 return error;
702 err_put:
703 if (po->pppoe_dev) {
704 dev_put(po->pppoe_dev);
705 po->pppoe_dev = NULL;
707 goto end;
710 static int pppoe_getname(struct socket *sock, struct sockaddr *uaddr,
711 int *usockaddr_len, int peer)
713 int len = sizeof(struct sockaddr_pppox);
714 struct sockaddr_pppox sp;
716 sp.sa_family = AF_PPPOX;
717 sp.sa_protocol = PX_PROTO_OE;
718 memcpy(&sp.sa_addr.pppoe, &pppox_sk(sock->sk)->pppoe_pa,
719 sizeof(struct pppoe_addr));
721 memcpy(uaddr, &sp, len);
723 *usockaddr_len = len;
725 return 0;
728 static int pppoe_ioctl(struct socket *sock, unsigned int cmd,
729 unsigned long arg)
731 struct sock *sk = sock->sk;
732 struct pppox_sock *po = pppox_sk(sk);
733 int val;
734 int err;
736 switch (cmd) {
737 case PPPIOCGMRU:
738 err = -ENXIO;
739 if (!(sk->sk_state & PPPOX_CONNECTED))
740 break;
742 err = -EFAULT;
743 if (put_user(po->pppoe_dev->mtu -
744 sizeof(struct pppoe_hdr) -
745 PPP_HDRLEN,
746 (int __user *)arg))
747 break;
748 err = 0;
749 break;
751 case PPPIOCSMRU:
752 err = -ENXIO;
753 if (!(sk->sk_state & PPPOX_CONNECTED))
754 break;
756 err = -EFAULT;
757 if (get_user(val, (int __user *)arg))
758 break;
760 if (val < (po->pppoe_dev->mtu
761 - sizeof(struct pppoe_hdr)
762 - PPP_HDRLEN))
763 err = 0;
764 else
765 err = -EINVAL;
766 break;
768 case PPPIOCSFLAGS:
769 err = -EFAULT;
770 if (get_user(val, (int __user *)arg))
771 break;
772 err = 0;
773 break;
775 case PPPOEIOCSFWD:
777 struct pppox_sock *relay_po;
779 err = -EBUSY;
780 if (sk->sk_state & (PPPOX_BOUND | PPPOX_ZOMBIE | PPPOX_DEAD))
781 break;
783 err = -ENOTCONN;
784 if (!(sk->sk_state & PPPOX_CONNECTED))
785 break;
787 /* PPPoE address from the user specifies an outbound
788 PPPoE address which frames are forwarded to */
789 err = -EFAULT;
790 if (copy_from_user(&po->pppoe_relay,
791 (void __user *)arg,
792 sizeof(struct sockaddr_pppox)))
793 break;
795 err = -EINVAL;
796 if (po->pppoe_relay.sa_family != AF_PPPOX ||
797 po->pppoe_relay.sa_protocol != PX_PROTO_OE)
798 break;
800 /* Check that the socket referenced by the address
801 actually exists. */
802 relay_po = get_item_by_addr(sock_net(sk), &po->pppoe_relay);
803 if (!relay_po)
804 break;
806 sock_put(sk_pppox(relay_po));
807 sk->sk_state |= PPPOX_RELAY;
808 err = 0;
809 break;
812 case PPPOEIOCDFWD:
813 err = -EALREADY;
814 if (!(sk->sk_state & PPPOX_RELAY))
815 break;
817 sk->sk_state &= ~PPPOX_RELAY;
818 err = 0;
819 break;
821 default:
822 err = -ENOTTY;
825 return err;
828 static int pppoe_sendmsg(struct kiocb *iocb, struct socket *sock,
829 struct msghdr *m, size_t total_len)
831 struct sk_buff *skb;
832 struct sock *sk = sock->sk;
833 struct pppox_sock *po = pppox_sk(sk);
834 int error;
835 struct pppoe_hdr hdr;
836 struct pppoe_hdr *ph;
837 struct net_device *dev;
838 char *start;
840 lock_sock(sk);
841 if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED)) {
842 error = -ENOTCONN;
843 goto end;
846 hdr.ver = 1;
847 hdr.type = 1;
848 hdr.code = 0;
849 hdr.sid = po->num;
851 dev = po->pppoe_dev;
853 error = -EMSGSIZE;
854 if (total_len > (dev->mtu + dev->hard_header_len))
855 goto end;
858 skb = sock_wmalloc(sk, total_len + dev->hard_header_len + 32,
859 0, GFP_KERNEL);
860 if (!skb) {
861 error = -ENOMEM;
862 goto end;
865 /* Reserve space for headers. */
866 skb_reserve(skb, dev->hard_header_len);
867 skb_reset_network_header(skb);
869 skb->dev = dev;
871 skb->priority = sk->sk_priority;
872 skb->protocol = cpu_to_be16(ETH_P_PPP_SES);
874 ph = (struct pppoe_hdr *)skb_put(skb, total_len + sizeof(struct pppoe_hdr));
875 start = (char *)&ph->tag[0];
877 error = memcpy_fromiovec(start, m->msg_iov, total_len);
878 if (error < 0) {
879 kfree_skb(skb);
880 goto end;
883 error = total_len;
884 dev_hard_header(skb, dev, ETH_P_PPP_SES,
885 po->pppoe_pa.remote, NULL, total_len);
887 memcpy(ph, &hdr, sizeof(struct pppoe_hdr));
889 ph->length = htons(total_len);
891 dev_queue_xmit(skb);
893 end:
894 release_sock(sk);
895 return error;
898 /************************************************************************
900 * xmit function for internal use.
902 ***********************************************************************/
903 static int __pppoe_xmit(struct sock *sk, struct sk_buff *skb)
905 struct pppox_sock *po = pppox_sk(sk);
906 struct net_device *dev = po->pppoe_dev;
907 struct pppoe_hdr *ph;
908 int data_len = skb->len;
910 /* The higher-level PPP code (ppp_unregister_channel()) ensures the PPP
911 * xmit operations conclude prior to an unregistration call. Thus
912 * sk->sk_state cannot change, so we don't need to do lock_sock().
913 * But, we also can't do a lock_sock since that introduces a potential
914 * deadlock as we'd reverse the lock ordering used when calling
915 * ppp_unregister_channel().
918 if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED))
919 goto abort;
921 if (!dev)
922 goto abort;
924 /* Copy the data if there is no space for the header or if it's
925 * read-only.
927 if (skb_cow_head(skb, sizeof(*ph) + dev->hard_header_len))
928 goto abort;
930 __skb_push(skb, sizeof(*ph));
931 skb_reset_network_header(skb);
933 ph = pppoe_hdr(skb);
934 ph->ver = 1;
935 ph->type = 1;
936 ph->code = 0;
937 ph->sid = po->num;
938 ph->length = htons(data_len);
940 skb->protocol = cpu_to_be16(ETH_P_PPP_SES);
941 skb->dev = dev;
943 dev_hard_header(skb, dev, ETH_P_PPP_SES,
944 po->pppoe_pa.remote, NULL, data_len);
946 dev_queue_xmit(skb);
947 return 1;
949 abort:
950 kfree_skb(skb);
951 return 1;
954 /************************************************************************
956 * xmit function called by generic PPP driver
957 * sends PPP frame over PPPoE socket
959 ***********************************************************************/
960 static int pppoe_xmit(struct ppp_channel *chan, struct sk_buff *skb)
962 struct sock *sk = (struct sock *)chan->private;
963 return __pppoe_xmit(sk, skb);
966 static const struct ppp_channel_ops pppoe_chan_ops = {
967 .start_xmit = pppoe_xmit,
970 static int pppoe_recvmsg(struct kiocb *iocb, struct socket *sock,
971 struct msghdr *m, size_t total_len, int flags)
973 struct sock *sk = sock->sk;
974 struct sk_buff *skb;
975 int error = 0;
977 if (sk->sk_state & PPPOX_BOUND) {
978 error = -EIO;
979 goto end;
982 skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
983 flags & MSG_DONTWAIT, &error);
984 if (error < 0)
985 goto end;
987 m->msg_namelen = 0;
989 if (skb) {
990 total_len = min_t(size_t, total_len, skb->len);
991 error = skb_copy_datagram_iovec(skb, 0, m->msg_iov, total_len);
992 if (error == 0)
993 error = total_len;
996 kfree_skb(skb);
997 end:
998 return error;
1001 #ifdef CONFIG_PROC_FS
1002 static int pppoe_seq_show(struct seq_file *seq, void *v)
1004 struct pppox_sock *po;
1005 char *dev_name;
1007 if (v == SEQ_START_TOKEN) {
1008 seq_puts(seq, "Id Address Device\n");
1009 goto out;
1012 po = v;
1013 dev_name = po->pppoe_pa.dev;
1015 seq_printf(seq, "%08X %pM %8s\n",
1016 po->pppoe_pa.sid, po->pppoe_pa.remote, dev_name);
1017 out:
1018 return 0;
1021 static inline struct pppox_sock *pppoe_get_idx(struct pppoe_net *pn, loff_t pos)
1023 struct pppox_sock *po;
1024 int i;
1026 for (i = 0; i < PPPOE_HASH_SIZE; i++) {
1027 po = pn->hash_table[i];
1028 while (po) {
1029 if (!pos--)
1030 goto out;
1031 po = po->next;
1035 out:
1036 return po;
1039 static void *pppoe_seq_start(struct seq_file *seq, loff_t *pos)
1040 __acquires(pn->hash_lock)
1042 struct pppoe_net *pn = pppoe_pernet(seq_file_net(seq));
1043 loff_t l = *pos;
1045 read_lock_bh(&pn->hash_lock);
1046 return l ? pppoe_get_idx(pn, --l) : SEQ_START_TOKEN;
1049 static void *pppoe_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1051 struct pppoe_net *pn = pppoe_pernet(seq_file_net(seq));
1052 struct pppox_sock *po;
1054 ++*pos;
1055 if (v == SEQ_START_TOKEN) {
1056 po = pppoe_get_idx(pn, 0);
1057 goto out;
1059 po = v;
1060 if (po->next)
1061 po = po->next;
1062 else {
1063 int hash = hash_item(po->pppoe_pa.sid, po->pppoe_pa.remote);
1065 po = NULL;
1066 while (++hash < PPPOE_HASH_SIZE) {
1067 po = pn->hash_table[hash];
1068 if (po)
1069 break;
1073 out:
1074 return po;
1077 static void pppoe_seq_stop(struct seq_file *seq, void *v)
1078 __releases(pn->hash_lock)
1080 struct pppoe_net *pn = pppoe_pernet(seq_file_net(seq));
1081 read_unlock_bh(&pn->hash_lock);
1084 static const struct seq_operations pppoe_seq_ops = {
1085 .start = pppoe_seq_start,
1086 .next = pppoe_seq_next,
1087 .stop = pppoe_seq_stop,
1088 .show = pppoe_seq_show,
1091 static int pppoe_seq_open(struct inode *inode, struct file *file)
1093 return seq_open_net(inode, file, &pppoe_seq_ops,
1094 sizeof(struct seq_net_private));
1097 static const struct file_operations pppoe_seq_fops = {
1098 .owner = THIS_MODULE,
1099 .open = pppoe_seq_open,
1100 .read = seq_read,
1101 .llseek = seq_lseek,
1102 .release = seq_release_net,
1105 #endif /* CONFIG_PROC_FS */
1107 static const struct proto_ops pppoe_ops = {
1108 .family = AF_PPPOX,
1109 .owner = THIS_MODULE,
1110 .release = pppoe_release,
1111 .bind = sock_no_bind,
1112 .connect = pppoe_connect,
1113 .socketpair = sock_no_socketpair,
1114 .accept = sock_no_accept,
1115 .getname = pppoe_getname,
1116 .poll = datagram_poll,
1117 .listen = sock_no_listen,
1118 .shutdown = sock_no_shutdown,
1119 .setsockopt = sock_no_setsockopt,
1120 .getsockopt = sock_no_getsockopt,
1121 .sendmsg = pppoe_sendmsg,
1122 .recvmsg = pppoe_recvmsg,
1123 .mmap = sock_no_mmap,
1124 .ioctl = pppox_ioctl,
1127 static const struct pppox_proto pppoe_proto = {
1128 .create = pppoe_create,
1129 .ioctl = pppoe_ioctl,
1130 .owner = THIS_MODULE,
1133 static __net_init int pppoe_init_net(struct net *net)
1135 struct pppoe_net *pn = pppoe_pernet(net);
1136 struct proc_dir_entry *pde;
1138 rwlock_init(&pn->hash_lock);
1140 pde = proc_net_fops_create(net, "pppoe", S_IRUGO, &pppoe_seq_fops);
1141 #ifdef CONFIG_PROC_FS
1142 if (!pde)
1143 return -ENOMEM;
1144 #endif
1146 return 0;
1149 static __net_exit void pppoe_exit_net(struct net *net)
1151 proc_net_remove(net, "pppoe");
1154 static struct pernet_operations pppoe_net_ops = {
1155 .init = pppoe_init_net,
1156 .exit = pppoe_exit_net,
1157 .id = &pppoe_net_id,
1158 .size = sizeof(struct pppoe_net),
1161 static int __init pppoe_init(void)
1163 int err;
1165 err = register_pernet_device(&pppoe_net_ops);
1166 if (err)
1167 goto out;
1169 err = proto_register(&pppoe_sk_proto, 0);
1170 if (err)
1171 goto out_unregister_net_ops;
1173 err = register_pppox_proto(PX_PROTO_OE, &pppoe_proto);
1174 if (err)
1175 goto out_unregister_pppoe_proto;
1177 dev_add_pack(&pppoes_ptype);
1178 dev_add_pack(&pppoed_ptype);
1179 register_netdevice_notifier(&pppoe_notifier);
1181 return 0;
1183 out_unregister_pppoe_proto:
1184 proto_unregister(&pppoe_sk_proto);
1185 out_unregister_net_ops:
1186 unregister_pernet_device(&pppoe_net_ops);
1187 out:
1188 return err;
1191 static void __exit pppoe_exit(void)
1193 unregister_netdevice_notifier(&pppoe_notifier);
1194 dev_remove_pack(&pppoed_ptype);
1195 dev_remove_pack(&pppoes_ptype);
1196 unregister_pppox_proto(PX_PROTO_OE);
1197 proto_unregister(&pppoe_sk_proto);
1198 unregister_pernet_device(&pppoe_net_ops);
1201 module_init(pppoe_init);
1202 module_exit(pppoe_exit);
1204 MODULE_AUTHOR("Michal Ostrowski <mostrows@speakeasy.net>");
1205 MODULE_DESCRIPTION("PPP over Ethernet driver");
1206 MODULE_LICENSE("GPL");
1207 MODULE_ALIAS_NETPROTO(PF_PPPOX);