Linux 4.16.11
[linux/fpc-iii.git] / drivers / net / ppp / pppoe.c
blob71e2aef6b7a1b5cdb052fed4aeec2a843a1a9a4d
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/ppp-ioctl.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 <linux/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 unsigned 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 simpler 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 && ether_addr_equal(a->remote, b->remote);
137 static inline int cmp_addr(struct pppoe_addr *a, __be16 sid, char *addr)
139 return a->sid == sid && ether_addr_equal(a->remote, addr);
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 void __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;
225 /**********************************************************************
227 * Set/get/delete/rehash items
229 **********************************************************************/
230 static inline struct pppox_sock *get_item(struct pppoe_net *pn, __be16 sid,
231 unsigned char *addr, int ifindex)
233 struct pppox_sock *po;
235 read_lock_bh(&pn->hash_lock);
236 po = __get_item(pn, sid, addr, ifindex);
237 if (po)
238 sock_hold(sk_pppox(po));
239 read_unlock_bh(&pn->hash_lock);
241 return po;
244 static inline struct pppox_sock *get_item_by_addr(struct net *net,
245 struct sockaddr_pppox *sp)
247 struct net_device *dev;
248 struct pppoe_net *pn;
249 struct pppox_sock *pppox_sock = NULL;
251 int ifindex;
253 rcu_read_lock();
254 dev = dev_get_by_name_rcu(net, sp->sa_addr.pppoe.dev);
255 if (dev) {
256 ifindex = dev->ifindex;
257 pn = pppoe_pernet(net);
258 pppox_sock = get_item(pn, sp->sa_addr.pppoe.sid,
259 sp->sa_addr.pppoe.remote, ifindex);
261 rcu_read_unlock();
262 return pppox_sock;
265 static inline void delete_item(struct pppoe_net *pn, __be16 sid,
266 char *addr, int ifindex)
268 write_lock_bh(&pn->hash_lock);
269 __delete_item(pn, sid, addr, ifindex);
270 write_unlock_bh(&pn->hash_lock);
273 /***************************************************************************
275 * Handler for device events.
276 * Certain device events require that sockets be unconnected.
278 **************************************************************************/
280 static void pppoe_flush_dev(struct net_device *dev)
282 struct pppoe_net *pn;
283 int i;
285 pn = pppoe_pernet(dev_net(dev));
286 write_lock_bh(&pn->hash_lock);
287 for (i = 0; i < PPPOE_HASH_SIZE; i++) {
288 struct pppox_sock *po = pn->hash_table[i];
289 struct sock *sk;
291 while (po) {
292 while (po && po->pppoe_dev != dev) {
293 po = po->next;
296 if (!po)
297 break;
299 sk = sk_pppox(po);
301 /* We always grab the socket lock, followed by the
302 * 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.
309 sock_hold(sk);
310 write_unlock_bh(&pn->hash_lock);
311 lock_sock(sk);
313 if (po->pppoe_dev == dev &&
314 sk->sk_state & (PPPOX_CONNECTED | PPPOX_BOUND)) {
315 pppox_unbind_sock(sk);
316 sk->sk_state_change(sk);
317 po->pppoe_dev = NULL;
318 dev_put(dev);
321 release_sock(sk);
322 sock_put(sk);
324 /* Restart the process from the start of the current
325 * hash chain. We dropped locks so the world may have
326 * change from underneath us.
329 BUG_ON(pppoe_pernet(dev_net(dev)) == NULL);
330 write_lock_bh(&pn->hash_lock);
331 po = pn->hash_table[i];
334 write_unlock_bh(&pn->hash_lock);
337 static int pppoe_device_event(struct notifier_block *this,
338 unsigned long event, void *ptr)
340 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
342 /* Only look at sockets that are using this specific device. */
343 switch (event) {
344 case NETDEV_CHANGEADDR:
345 case NETDEV_CHANGEMTU:
346 /* A change in mtu or address is a bad thing, requiring
347 * LCP re-negotiation.
350 case NETDEV_GOING_DOWN:
351 case NETDEV_DOWN:
352 /* Find every socket on this device and kill it. */
353 pppoe_flush_dev(dev);
354 break;
356 default:
357 break;
360 return NOTIFY_DONE;
363 static struct notifier_block pppoe_notifier = {
364 .notifier_call = pppoe_device_event,
367 /************************************************************************
369 * Do the real work of receiving a PPPoE Session frame.
371 ***********************************************************************/
372 static int pppoe_rcv_core(struct sock *sk, struct sk_buff *skb)
374 struct pppox_sock *po = pppox_sk(sk);
375 struct pppox_sock *relay_po;
377 /* Backlog receive. Semantics of backlog rcv preclude any code from
378 * executing in lock_sock()/release_sock() bounds; meaning sk->sk_state
379 * can't change.
382 if (skb->pkt_type == PACKET_OTHERHOST)
383 goto abort_kfree;
385 if (sk->sk_state & PPPOX_BOUND) {
386 ppp_input(&po->chan, skb);
387 } else if (sk->sk_state & PPPOX_RELAY) {
388 relay_po = get_item_by_addr(sock_net(sk),
389 &po->pppoe_relay);
390 if (relay_po == NULL)
391 goto abort_kfree;
393 if ((sk_pppox(relay_po)->sk_state & PPPOX_CONNECTED) == 0)
394 goto abort_put;
396 if (!__pppoe_xmit(sk_pppox(relay_po), skb))
397 goto abort_put;
399 sock_put(sk_pppox(relay_po));
400 } else {
401 if (sock_queue_rcv_skb(sk, skb))
402 goto abort_kfree;
405 return NET_RX_SUCCESS;
407 abort_put:
408 sock_put(sk_pppox(relay_po));
410 abort_kfree:
411 kfree_skb(skb);
412 return NET_RX_DROP;
415 /************************************************************************
417 * Receive wrapper called in BH context.
419 ***********************************************************************/
420 static int pppoe_rcv(struct sk_buff *skb, struct net_device *dev,
421 struct packet_type *pt, struct net_device *orig_dev)
423 struct pppoe_hdr *ph;
424 struct pppox_sock *po;
425 struct pppoe_net *pn;
426 int len;
428 skb = skb_share_check(skb, GFP_ATOMIC);
429 if (!skb)
430 goto out;
432 if (!pskb_may_pull(skb, sizeof(struct pppoe_hdr)))
433 goto drop;
435 ph = pppoe_hdr(skb);
436 len = ntohs(ph->length);
438 skb_pull_rcsum(skb, sizeof(*ph));
439 if (skb->len < len)
440 goto drop;
442 if (pskb_trim_rcsum(skb, len))
443 goto drop;
445 pn = pppoe_pernet(dev_net(dev));
447 /* Note that get_item does a sock_hold(), so sk_pppox(po)
448 * is known to be safe.
450 po = get_item(pn, ph->sid, eth_hdr(skb)->h_source, dev->ifindex);
451 if (!po)
452 goto drop;
454 return sk_receive_skb(sk_pppox(po), skb, 0);
456 drop:
457 kfree_skb(skb);
458 out:
459 return NET_RX_DROP;
462 static void pppoe_unbind_sock_work(struct work_struct *work)
464 struct pppox_sock *po = container_of(work, struct pppox_sock,
465 proto.pppoe.padt_work);
466 struct sock *sk = sk_pppox(po);
468 lock_sock(sk);
469 if (po->pppoe_dev) {
470 dev_put(po->pppoe_dev);
471 po->pppoe_dev = NULL;
473 pppox_unbind_sock(sk);
474 release_sock(sk);
475 sock_put(sk);
478 /************************************************************************
480 * Receive a PPPoE Discovery frame.
481 * This is solely for detection of PADT frames
483 ***********************************************************************/
484 static int pppoe_disc_rcv(struct sk_buff *skb, struct net_device *dev,
485 struct packet_type *pt, struct net_device *orig_dev)
488 struct pppoe_hdr *ph;
489 struct pppox_sock *po;
490 struct pppoe_net *pn;
492 skb = skb_share_check(skb, GFP_ATOMIC);
493 if (!skb)
494 goto out;
496 if (!pskb_may_pull(skb, sizeof(struct pppoe_hdr)))
497 goto abort;
499 ph = pppoe_hdr(skb);
500 if (ph->code != PADT_CODE)
501 goto abort;
503 pn = pppoe_pernet(dev_net(dev));
504 po = get_item(pn, ph->sid, eth_hdr(skb)->h_source, dev->ifindex);
505 if (po)
506 if (!schedule_work(&po->proto.pppoe.padt_work))
507 sock_put(sk_pppox(po));
509 abort:
510 kfree_skb(skb);
511 out:
512 return NET_RX_SUCCESS; /* Lies... :-) */
515 static struct packet_type pppoes_ptype __read_mostly = {
516 .type = cpu_to_be16(ETH_P_PPP_SES),
517 .func = pppoe_rcv,
520 static struct packet_type pppoed_ptype __read_mostly = {
521 .type = cpu_to_be16(ETH_P_PPP_DISC),
522 .func = pppoe_disc_rcv,
525 static struct proto pppoe_sk_proto __read_mostly = {
526 .name = "PPPOE",
527 .owner = THIS_MODULE,
528 .obj_size = sizeof(struct pppox_sock),
531 /***********************************************************************
533 * Initialize a new struct sock.
535 **********************************************************************/
536 static int pppoe_create(struct net *net, struct socket *sock, int kern)
538 struct sock *sk;
540 sk = sk_alloc(net, PF_PPPOX, GFP_KERNEL, &pppoe_sk_proto, kern);
541 if (!sk)
542 return -ENOMEM;
544 sock_init_data(sock, sk);
546 sock->state = SS_UNCONNECTED;
547 sock->ops = &pppoe_ops;
549 sk->sk_backlog_rcv = pppoe_rcv_core;
550 sk->sk_state = PPPOX_NONE;
551 sk->sk_type = SOCK_STREAM;
552 sk->sk_family = PF_PPPOX;
553 sk->sk_protocol = PX_PROTO_OE;
555 INIT_WORK(&pppox_sk(sk)->proto.pppoe.padt_work,
556 pppoe_unbind_sock_work);
558 return 0;
561 static int pppoe_release(struct socket *sock)
563 struct sock *sk = sock->sk;
564 struct pppox_sock *po;
565 struct pppoe_net *pn;
566 struct net *net = NULL;
568 if (!sk)
569 return 0;
571 lock_sock(sk);
572 if (sock_flag(sk, SOCK_DEAD)) {
573 release_sock(sk);
574 return -EBADF;
577 po = pppox_sk(sk);
579 if (po->pppoe_dev) {
580 dev_put(po->pppoe_dev);
581 po->pppoe_dev = NULL;
584 pppox_unbind_sock(sk);
586 /* Signal the death of the socket. */
587 sk->sk_state = PPPOX_DEAD;
589 net = sock_net(sk);
590 pn = pppoe_pernet(net);
593 * protect "po" from concurrent updates
594 * on pppoe_flush_dev
596 delete_item(pn, po->pppoe_pa.sid, po->pppoe_pa.remote,
597 po->pppoe_ifindex);
599 sock_orphan(sk);
600 sock->sk = NULL;
602 skb_queue_purge(&sk->sk_receive_queue);
603 release_sock(sk);
604 sock_put(sk);
606 return 0;
609 static int pppoe_connect(struct socket *sock, struct sockaddr *uservaddr,
610 int sockaddr_len, int flags)
612 struct sock *sk = sock->sk;
613 struct sockaddr_pppox *sp = (struct sockaddr_pppox *)uservaddr;
614 struct pppox_sock *po = pppox_sk(sk);
615 struct net_device *dev = NULL;
616 struct pppoe_net *pn;
617 struct net *net = NULL;
618 int error;
620 lock_sock(sk);
622 error = -EINVAL;
624 if (sockaddr_len != sizeof(struct sockaddr_pppox))
625 goto end;
627 if (sp->sa_protocol != PX_PROTO_OE)
628 goto end;
630 /* Check for already bound sockets */
631 error = -EBUSY;
632 if ((sk->sk_state & PPPOX_CONNECTED) &&
633 stage_session(sp->sa_addr.pppoe.sid))
634 goto end;
636 /* Check for already disconnected sockets, on attempts to disconnect */
637 error = -EALREADY;
638 if ((sk->sk_state & PPPOX_DEAD) &&
639 !stage_session(sp->sa_addr.pppoe.sid))
640 goto end;
642 error = 0;
644 /* Delete the old binding */
645 if (stage_session(po->pppoe_pa.sid)) {
646 pppox_unbind_sock(sk);
647 pn = pppoe_pernet(sock_net(sk));
648 delete_item(pn, po->pppoe_pa.sid,
649 po->pppoe_pa.remote, po->pppoe_ifindex);
650 if (po->pppoe_dev) {
651 dev_put(po->pppoe_dev);
652 po->pppoe_dev = NULL;
655 po->pppoe_ifindex = 0;
656 memset(&po->pppoe_pa, 0, sizeof(po->pppoe_pa));
657 memset(&po->pppoe_relay, 0, sizeof(po->pppoe_relay));
658 memset(&po->chan, 0, sizeof(po->chan));
659 po->next = NULL;
660 po->num = 0;
662 sk->sk_state = PPPOX_NONE;
665 /* Re-bind in session stage only */
666 if (stage_session(sp->sa_addr.pppoe.sid)) {
667 error = -ENODEV;
668 net = sock_net(sk);
669 dev = dev_get_by_name(net, sp->sa_addr.pppoe.dev);
670 if (!dev)
671 goto err_put;
673 po->pppoe_dev = dev;
674 po->pppoe_ifindex = dev->ifindex;
675 pn = pppoe_pernet(net);
676 if (!(dev->flags & IFF_UP)) {
677 goto err_put;
680 memcpy(&po->pppoe_pa,
681 &sp->sa_addr.pppoe,
682 sizeof(struct pppoe_addr));
684 write_lock_bh(&pn->hash_lock);
685 error = __set_item(pn, po);
686 write_unlock_bh(&pn->hash_lock);
687 if (error < 0)
688 goto err_put;
690 po->chan.hdrlen = (sizeof(struct pppoe_hdr) +
691 dev->hard_header_len);
693 po->chan.mtu = dev->mtu - sizeof(struct pppoe_hdr) - 2;
694 po->chan.private = sk;
695 po->chan.ops = &pppoe_chan_ops;
697 error = ppp_register_net_channel(dev_net(dev), &po->chan);
698 if (error) {
699 delete_item(pn, po->pppoe_pa.sid,
700 po->pppoe_pa.remote, po->pppoe_ifindex);
701 goto err_put;
704 sk->sk_state = PPPOX_CONNECTED;
707 po->num = sp->sa_addr.pppoe.sid;
709 end:
710 release_sock(sk);
711 return error;
712 err_put:
713 if (po->pppoe_dev) {
714 dev_put(po->pppoe_dev);
715 po->pppoe_dev = NULL;
717 goto end;
720 static int pppoe_getname(struct socket *sock, struct sockaddr *uaddr,
721 int *usockaddr_len, int peer)
723 int len = sizeof(struct sockaddr_pppox);
724 struct sockaddr_pppox sp;
726 sp.sa_family = AF_PPPOX;
727 sp.sa_protocol = PX_PROTO_OE;
728 memcpy(&sp.sa_addr.pppoe, &pppox_sk(sock->sk)->pppoe_pa,
729 sizeof(struct pppoe_addr));
731 memcpy(uaddr, &sp, len);
733 *usockaddr_len = len;
735 return 0;
738 static int pppoe_ioctl(struct socket *sock, unsigned int cmd,
739 unsigned long arg)
741 struct sock *sk = sock->sk;
742 struct pppox_sock *po = pppox_sk(sk);
743 int val;
744 int err;
746 switch (cmd) {
747 case PPPIOCGMRU:
748 err = -ENXIO;
749 if (!(sk->sk_state & PPPOX_CONNECTED))
750 break;
752 err = -EFAULT;
753 if (put_user(po->pppoe_dev->mtu -
754 sizeof(struct pppoe_hdr) -
755 PPP_HDRLEN,
756 (int __user *)arg))
757 break;
758 err = 0;
759 break;
761 case PPPIOCSMRU:
762 err = -ENXIO;
763 if (!(sk->sk_state & PPPOX_CONNECTED))
764 break;
766 err = -EFAULT;
767 if (get_user(val, (int __user *)arg))
768 break;
770 if (val < (po->pppoe_dev->mtu
771 - sizeof(struct pppoe_hdr)
772 - PPP_HDRLEN))
773 err = 0;
774 else
775 err = -EINVAL;
776 break;
778 case PPPIOCSFLAGS:
779 err = -EFAULT;
780 if (get_user(val, (int __user *)arg))
781 break;
782 err = 0;
783 break;
785 case PPPOEIOCSFWD:
787 struct pppox_sock *relay_po;
789 err = -EBUSY;
790 if (sk->sk_state & (PPPOX_BOUND | PPPOX_DEAD))
791 break;
793 err = -ENOTCONN;
794 if (!(sk->sk_state & PPPOX_CONNECTED))
795 break;
797 /* PPPoE address from the user specifies an outbound
798 PPPoE address which frames are forwarded to */
799 err = -EFAULT;
800 if (copy_from_user(&po->pppoe_relay,
801 (void __user *)arg,
802 sizeof(struct sockaddr_pppox)))
803 break;
805 err = -EINVAL;
806 if (po->pppoe_relay.sa_family != AF_PPPOX ||
807 po->pppoe_relay.sa_protocol != PX_PROTO_OE)
808 break;
810 /* Check that the socket referenced by the address
811 actually exists. */
812 relay_po = get_item_by_addr(sock_net(sk), &po->pppoe_relay);
813 if (!relay_po)
814 break;
816 sock_put(sk_pppox(relay_po));
817 sk->sk_state |= PPPOX_RELAY;
818 err = 0;
819 break;
822 case PPPOEIOCDFWD:
823 err = -EALREADY;
824 if (!(sk->sk_state & PPPOX_RELAY))
825 break;
827 sk->sk_state &= ~PPPOX_RELAY;
828 err = 0;
829 break;
831 default:
832 err = -ENOTTY;
835 return err;
838 static int pppoe_sendmsg(struct socket *sock, struct msghdr *m,
839 size_t total_len)
841 struct sk_buff *skb;
842 struct sock *sk = sock->sk;
843 struct pppox_sock *po = pppox_sk(sk);
844 int error;
845 struct pppoe_hdr hdr;
846 struct pppoe_hdr *ph;
847 struct net_device *dev;
848 char *start;
849 int hlen;
851 lock_sock(sk);
852 if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED)) {
853 error = -ENOTCONN;
854 goto end;
857 hdr.ver = 1;
858 hdr.type = 1;
859 hdr.code = 0;
860 hdr.sid = po->num;
862 dev = po->pppoe_dev;
864 error = -EMSGSIZE;
865 if (total_len > (dev->mtu + dev->hard_header_len))
866 goto end;
868 hlen = LL_RESERVED_SPACE(dev);
869 skb = sock_wmalloc(sk, hlen + sizeof(*ph) + total_len +
870 dev->needed_tailroom, 0, GFP_KERNEL);
871 if (!skb) {
872 error = -ENOMEM;
873 goto end;
876 /* Reserve space for headers. */
877 skb_reserve(skb, hlen);
878 skb_reset_network_header(skb);
880 skb->dev = dev;
882 skb->priority = sk->sk_priority;
883 skb->protocol = cpu_to_be16(ETH_P_PPP_SES);
885 ph = skb_put(skb, total_len + sizeof(struct pppoe_hdr));
886 start = (char *)&ph->tag[0];
888 error = memcpy_from_msg(start, m, total_len);
889 if (error < 0) {
890 kfree_skb(skb);
891 goto end;
894 error = total_len;
895 dev_hard_header(skb, dev, ETH_P_PPP_SES,
896 po->pppoe_pa.remote, NULL, total_len);
898 memcpy(ph, &hdr, sizeof(struct pppoe_hdr));
900 ph->length = htons(total_len);
902 dev_queue_xmit(skb);
904 end:
905 release_sock(sk);
906 return error;
909 /************************************************************************
911 * xmit function for internal use.
913 ***********************************************************************/
914 static int __pppoe_xmit(struct sock *sk, struct sk_buff *skb)
916 struct pppox_sock *po = pppox_sk(sk);
917 struct net_device *dev = po->pppoe_dev;
918 struct pppoe_hdr *ph;
919 int data_len = skb->len;
921 /* The higher-level PPP code (ppp_unregister_channel()) ensures the PPP
922 * xmit operations conclude prior to an unregistration call. Thus
923 * sk->sk_state cannot change, so we don't need to do lock_sock().
924 * But, we also can't do a lock_sock since that introduces a potential
925 * deadlock as we'd reverse the lock ordering used when calling
926 * ppp_unregister_channel().
929 if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED))
930 goto abort;
932 if (!dev)
933 goto abort;
935 /* Copy the data if there is no space for the header or if it's
936 * read-only.
938 if (skb_cow_head(skb, LL_RESERVED_SPACE(dev) + sizeof(*ph)))
939 goto abort;
941 __skb_push(skb, sizeof(*ph));
942 skb_reset_network_header(skb);
944 ph = pppoe_hdr(skb);
945 ph->ver = 1;
946 ph->type = 1;
947 ph->code = 0;
948 ph->sid = po->num;
949 ph->length = htons(data_len);
951 skb->protocol = cpu_to_be16(ETH_P_PPP_SES);
952 skb->dev = dev;
954 dev_hard_header(skb, dev, ETH_P_PPP_SES,
955 po->pppoe_pa.remote, NULL, data_len);
957 dev_queue_xmit(skb);
958 return 1;
960 abort:
961 kfree_skb(skb);
962 return 1;
965 /************************************************************************
967 * xmit function called by generic PPP driver
968 * sends PPP frame over PPPoE socket
970 ***********************************************************************/
971 static int pppoe_xmit(struct ppp_channel *chan, struct sk_buff *skb)
973 struct sock *sk = (struct sock *)chan->private;
974 return __pppoe_xmit(sk, skb);
977 static const struct ppp_channel_ops pppoe_chan_ops = {
978 .start_xmit = pppoe_xmit,
981 static int pppoe_recvmsg(struct socket *sock, struct msghdr *m,
982 size_t total_len, int flags)
984 struct sock *sk = sock->sk;
985 struct sk_buff *skb;
986 int error = 0;
988 if (sk->sk_state & PPPOX_BOUND) {
989 error = -EIO;
990 goto end;
993 skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
994 flags & MSG_DONTWAIT, &error);
995 if (error < 0)
996 goto end;
998 if (skb) {
999 total_len = min_t(size_t, total_len, skb->len);
1000 error = skb_copy_datagram_msg(skb, 0, m, total_len);
1001 if (error == 0) {
1002 consume_skb(skb);
1003 return total_len;
1007 kfree_skb(skb);
1008 end:
1009 return error;
1012 #ifdef CONFIG_PROC_FS
1013 static int pppoe_seq_show(struct seq_file *seq, void *v)
1015 struct pppox_sock *po;
1016 char *dev_name;
1018 if (v == SEQ_START_TOKEN) {
1019 seq_puts(seq, "Id Address Device\n");
1020 goto out;
1023 po = v;
1024 dev_name = po->pppoe_pa.dev;
1026 seq_printf(seq, "%08X %pM %8s\n",
1027 po->pppoe_pa.sid, po->pppoe_pa.remote, dev_name);
1028 out:
1029 return 0;
1032 static inline struct pppox_sock *pppoe_get_idx(struct pppoe_net *pn, loff_t pos)
1034 struct pppox_sock *po;
1035 int i;
1037 for (i = 0; i < PPPOE_HASH_SIZE; i++) {
1038 po = pn->hash_table[i];
1039 while (po) {
1040 if (!pos--)
1041 goto out;
1042 po = po->next;
1046 out:
1047 return po;
1050 static void *pppoe_seq_start(struct seq_file *seq, loff_t *pos)
1051 __acquires(pn->hash_lock)
1053 struct pppoe_net *pn = pppoe_pernet(seq_file_net(seq));
1054 loff_t l = *pos;
1056 read_lock_bh(&pn->hash_lock);
1057 return l ? pppoe_get_idx(pn, --l) : SEQ_START_TOKEN;
1060 static void *pppoe_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1062 struct pppoe_net *pn = pppoe_pernet(seq_file_net(seq));
1063 struct pppox_sock *po;
1065 ++*pos;
1066 if (v == SEQ_START_TOKEN) {
1067 po = pppoe_get_idx(pn, 0);
1068 goto out;
1070 po = v;
1071 if (po->next)
1072 po = po->next;
1073 else {
1074 int hash = hash_item(po->pppoe_pa.sid, po->pppoe_pa.remote);
1076 po = NULL;
1077 while (++hash < PPPOE_HASH_SIZE) {
1078 po = pn->hash_table[hash];
1079 if (po)
1080 break;
1084 out:
1085 return po;
1088 static void pppoe_seq_stop(struct seq_file *seq, void *v)
1089 __releases(pn->hash_lock)
1091 struct pppoe_net *pn = pppoe_pernet(seq_file_net(seq));
1092 read_unlock_bh(&pn->hash_lock);
1095 static const struct seq_operations pppoe_seq_ops = {
1096 .start = pppoe_seq_start,
1097 .next = pppoe_seq_next,
1098 .stop = pppoe_seq_stop,
1099 .show = pppoe_seq_show,
1102 static int pppoe_seq_open(struct inode *inode, struct file *file)
1104 return seq_open_net(inode, file, &pppoe_seq_ops,
1105 sizeof(struct seq_net_private));
1108 static const struct file_operations pppoe_seq_fops = {
1109 .owner = THIS_MODULE,
1110 .open = pppoe_seq_open,
1111 .read = seq_read,
1112 .llseek = seq_lseek,
1113 .release = seq_release_net,
1116 #endif /* CONFIG_PROC_FS */
1118 static const struct proto_ops pppoe_ops = {
1119 .family = AF_PPPOX,
1120 .owner = THIS_MODULE,
1121 .release = pppoe_release,
1122 .bind = sock_no_bind,
1123 .connect = pppoe_connect,
1124 .socketpair = sock_no_socketpair,
1125 .accept = sock_no_accept,
1126 .getname = pppoe_getname,
1127 .poll = datagram_poll,
1128 .listen = sock_no_listen,
1129 .shutdown = sock_no_shutdown,
1130 .setsockopt = sock_no_setsockopt,
1131 .getsockopt = sock_no_getsockopt,
1132 .sendmsg = pppoe_sendmsg,
1133 .recvmsg = pppoe_recvmsg,
1134 .mmap = sock_no_mmap,
1135 .ioctl = pppox_ioctl,
1138 static const struct pppox_proto pppoe_proto = {
1139 .create = pppoe_create,
1140 .ioctl = pppoe_ioctl,
1141 .owner = THIS_MODULE,
1144 static __net_init int pppoe_init_net(struct net *net)
1146 struct pppoe_net *pn = pppoe_pernet(net);
1147 struct proc_dir_entry *pde;
1149 rwlock_init(&pn->hash_lock);
1151 pde = proc_create("pppoe", S_IRUGO, net->proc_net, &pppoe_seq_fops);
1152 #ifdef CONFIG_PROC_FS
1153 if (!pde)
1154 return -ENOMEM;
1155 #endif
1157 return 0;
1160 static __net_exit void pppoe_exit_net(struct net *net)
1162 remove_proc_entry("pppoe", net->proc_net);
1165 static struct pernet_operations pppoe_net_ops = {
1166 .init = pppoe_init_net,
1167 .exit = pppoe_exit_net,
1168 .id = &pppoe_net_id,
1169 .size = sizeof(struct pppoe_net),
1172 static int __init pppoe_init(void)
1174 int err;
1176 err = register_pernet_device(&pppoe_net_ops);
1177 if (err)
1178 goto out;
1180 err = proto_register(&pppoe_sk_proto, 0);
1181 if (err)
1182 goto out_unregister_net_ops;
1184 err = register_pppox_proto(PX_PROTO_OE, &pppoe_proto);
1185 if (err)
1186 goto out_unregister_pppoe_proto;
1188 dev_add_pack(&pppoes_ptype);
1189 dev_add_pack(&pppoed_ptype);
1190 register_netdevice_notifier(&pppoe_notifier);
1192 return 0;
1194 out_unregister_pppoe_proto:
1195 proto_unregister(&pppoe_sk_proto);
1196 out_unregister_net_ops:
1197 unregister_pernet_device(&pppoe_net_ops);
1198 out:
1199 return err;
1202 static void __exit pppoe_exit(void)
1204 unregister_netdevice_notifier(&pppoe_notifier);
1205 dev_remove_pack(&pppoed_ptype);
1206 dev_remove_pack(&pppoes_ptype);
1207 unregister_pppox_proto(PX_PROTO_OE);
1208 proto_unregister(&pppoe_sk_proto);
1209 unregister_pernet_device(&pppoe_net_ops);
1212 module_init(pppoe_init);
1213 module_exit(pppoe_exit);
1215 MODULE_AUTHOR("Michal Ostrowski <mostrows@speakeasy.net>");
1216 MODULE_DESCRIPTION("PPP over Ethernet driver");
1217 MODULE_LICENSE("GPL");
1218 MODULE_ALIAS_NET_PF_PROTO(PF_PPPOX, PX_PROTO_OE);