treewide: remove redundant IS_ERR() before error code check
[linux/fpc-iii.git] / drivers / net / ppp / pppoe.c
blobd760a36db28cb43237bbad4309eaf509a5bf681d
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /** -*- linux-c -*- ***********************************************************
3 * Linux PPP over Ethernet (PPPoX/PPPoE) Sockets
5 * PPPoX --- Generic PPP encapsulation socket family
6 * 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:
55 #include <linux/string.h>
56 #include <linux/module.h>
57 #include <linux/kernel.h>
58 #include <linux/slab.h>
59 #include <linux/errno.h>
60 #include <linux/netdevice.h>
61 #include <linux/net.h>
62 #include <linux/inetdevice.h>
63 #include <linux/etherdevice.h>
64 #include <linux/skbuff.h>
65 #include <linux/init.h>
66 #include <linux/if_ether.h>
67 #include <linux/if_pppox.h>
68 #include <linux/ppp_channel.h>
69 #include <linux/ppp_defs.h>
70 #include <linux/ppp-ioctl.h>
71 #include <linux/notifier.h>
72 #include <linux/file.h>
73 #include <linux/proc_fs.h>
74 #include <linux/seq_file.h>
76 #include <linux/nsproxy.h>
77 #include <net/net_namespace.h>
78 #include <net/netns/generic.h>
79 #include <net/sock.h>
81 #include <linux/uaccess.h>
83 #define PPPOE_HASH_BITS 4
84 #define PPPOE_HASH_SIZE (1 << PPPOE_HASH_BITS)
85 #define PPPOE_HASH_MASK (PPPOE_HASH_SIZE - 1)
87 static int __pppoe_xmit(struct sock *sk, struct sk_buff *skb);
89 static const struct proto_ops pppoe_ops;
90 static const struct ppp_channel_ops pppoe_chan_ops;
92 /* per-net private data for this module */
93 static unsigned int pppoe_net_id __read_mostly;
94 struct pppoe_net {
96 * we could use _single_ hash table for all
97 * nets by injecting net id into the hash but
98 * it would increase hash chains and add
99 * a few additional math comparations messy
100 * as well, moreover in case of SMP less locking
101 * controversy here
103 struct pppox_sock *hash_table[PPPOE_HASH_SIZE];
104 rwlock_t hash_lock;
108 * PPPoE could be in the following stages:
109 * 1) Discovery stage (to obtain remote MAC and Session ID)
110 * 2) Session stage (MAC and SID are known)
112 * Ethernet frames have a special tag for this but
113 * we use simpler approach based on session id
115 static inline bool stage_session(__be16 sid)
117 return sid != 0;
120 static inline struct pppoe_net *pppoe_pernet(struct net *net)
122 return net_generic(net, pppoe_net_id);
125 static inline int cmp_2_addr(struct pppoe_addr *a, struct pppoe_addr *b)
127 return a->sid == b->sid && ether_addr_equal(a->remote, b->remote);
130 static inline int cmp_addr(struct pppoe_addr *a, __be16 sid, char *addr)
132 return a->sid == sid && ether_addr_equal(a->remote, addr);
135 #if 8 % PPPOE_HASH_BITS
136 #error 8 must be a multiple of PPPOE_HASH_BITS
137 #endif
139 static int hash_item(__be16 sid, unsigned char *addr)
141 unsigned char hash = 0;
142 unsigned int i;
144 for (i = 0; i < ETH_ALEN; i++)
145 hash ^= addr[i];
146 for (i = 0; i < sizeof(sid_t) * 8; i += 8)
147 hash ^= (__force __u32)sid >> i;
148 for (i = 8; (i >>= 1) >= PPPOE_HASH_BITS;)
149 hash ^= hash >> i;
151 return hash & PPPOE_HASH_MASK;
154 /**********************************************************************
156 * Set/get/delete/rehash items (internal versions)
158 **********************************************************************/
159 static struct pppox_sock *__get_item(struct pppoe_net *pn, __be16 sid,
160 unsigned char *addr, int ifindex)
162 int hash = hash_item(sid, addr);
163 struct pppox_sock *ret;
165 ret = pn->hash_table[hash];
166 while (ret) {
167 if (cmp_addr(&ret->pppoe_pa, sid, addr) &&
168 ret->pppoe_ifindex == ifindex)
169 return ret;
171 ret = ret->next;
174 return NULL;
177 static int __set_item(struct pppoe_net *pn, struct pppox_sock *po)
179 int hash = hash_item(po->pppoe_pa.sid, po->pppoe_pa.remote);
180 struct pppox_sock *ret;
182 ret = pn->hash_table[hash];
183 while (ret) {
184 if (cmp_2_addr(&ret->pppoe_pa, &po->pppoe_pa) &&
185 ret->pppoe_ifindex == po->pppoe_ifindex)
186 return -EALREADY;
188 ret = ret->next;
191 po->next = pn->hash_table[hash];
192 pn->hash_table[hash] = po;
194 return 0;
197 static void __delete_item(struct pppoe_net *pn, __be16 sid,
198 char *addr, int ifindex)
200 int hash = hash_item(sid, addr);
201 struct pppox_sock *ret, **src;
203 ret = pn->hash_table[hash];
204 src = &pn->hash_table[hash];
206 while (ret) {
207 if (cmp_addr(&ret->pppoe_pa, sid, addr) &&
208 ret->pppoe_ifindex == ifindex) {
209 *src = ret->next;
210 break;
213 src = &ret->next;
214 ret = ret->next;
218 /**********************************************************************
220 * Set/get/delete/rehash items
222 **********************************************************************/
223 static inline struct pppox_sock *get_item(struct pppoe_net *pn, __be16 sid,
224 unsigned char *addr, int ifindex)
226 struct pppox_sock *po;
228 read_lock_bh(&pn->hash_lock);
229 po = __get_item(pn, sid, addr, ifindex);
230 if (po)
231 sock_hold(sk_pppox(po));
232 read_unlock_bh(&pn->hash_lock);
234 return po;
237 static inline struct pppox_sock *get_item_by_addr(struct net *net,
238 struct sockaddr_pppox *sp)
240 struct net_device *dev;
241 struct pppoe_net *pn;
242 struct pppox_sock *pppox_sock = NULL;
244 int ifindex;
246 rcu_read_lock();
247 dev = dev_get_by_name_rcu(net, sp->sa_addr.pppoe.dev);
248 if (dev) {
249 ifindex = dev->ifindex;
250 pn = pppoe_pernet(net);
251 pppox_sock = get_item(pn, sp->sa_addr.pppoe.sid,
252 sp->sa_addr.pppoe.remote, ifindex);
254 rcu_read_unlock();
255 return pppox_sock;
258 static inline void delete_item(struct pppoe_net *pn, __be16 sid,
259 char *addr, int ifindex)
261 write_lock_bh(&pn->hash_lock);
262 __delete_item(pn, sid, addr, ifindex);
263 write_unlock_bh(&pn->hash_lock);
266 /***************************************************************************
268 * Handler for device events.
269 * Certain device events require that sockets be unconnected.
271 **************************************************************************/
273 static void pppoe_flush_dev(struct net_device *dev)
275 struct pppoe_net *pn;
276 int i;
278 pn = pppoe_pernet(dev_net(dev));
279 write_lock_bh(&pn->hash_lock);
280 for (i = 0; i < PPPOE_HASH_SIZE; i++) {
281 struct pppox_sock *po = pn->hash_table[i];
282 struct sock *sk;
284 while (po) {
285 while (po && po->pppoe_dev != dev) {
286 po = po->next;
289 if (!po)
290 break;
292 sk = sk_pppox(po);
294 /* We always grab the socket lock, followed by the
295 * hash_lock, in that order. Since we should hold the
296 * sock lock while doing any unbinding, we need to
297 * release the lock we're holding. Hold a reference to
298 * the sock so it doesn't disappear as we're jumping
299 * between locks.
302 sock_hold(sk);
303 write_unlock_bh(&pn->hash_lock);
304 lock_sock(sk);
306 if (po->pppoe_dev == dev &&
307 sk->sk_state & (PPPOX_CONNECTED | PPPOX_BOUND)) {
308 pppox_unbind_sock(sk);
309 sk->sk_state_change(sk);
310 po->pppoe_dev = NULL;
311 dev_put(dev);
314 release_sock(sk);
315 sock_put(sk);
317 /* Restart the process from the start of the current
318 * hash chain. We dropped locks so the world may have
319 * change from underneath us.
322 BUG_ON(pppoe_pernet(dev_net(dev)) == NULL);
323 write_lock_bh(&pn->hash_lock);
324 po = pn->hash_table[i];
327 write_unlock_bh(&pn->hash_lock);
330 static int pppoe_device_event(struct notifier_block *this,
331 unsigned long event, void *ptr)
333 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
335 /* Only look at sockets that are using this specific device. */
336 switch (event) {
337 case NETDEV_CHANGEADDR:
338 case NETDEV_CHANGEMTU:
339 /* A change in mtu or address is a bad thing, requiring
340 * LCP re-negotiation.
343 case NETDEV_GOING_DOWN:
344 case NETDEV_DOWN:
345 /* Find every socket on this device and kill it. */
346 pppoe_flush_dev(dev);
347 break;
349 default:
350 break;
353 return NOTIFY_DONE;
356 static struct notifier_block pppoe_notifier = {
357 .notifier_call = pppoe_device_event,
360 /************************************************************************
362 * Do the real work of receiving a PPPoE Session frame.
364 ***********************************************************************/
365 static int pppoe_rcv_core(struct sock *sk, struct sk_buff *skb)
367 struct pppox_sock *po = pppox_sk(sk);
368 struct pppox_sock *relay_po;
370 /* Backlog receive. Semantics of backlog rcv preclude any code from
371 * executing in lock_sock()/release_sock() bounds; meaning sk->sk_state
372 * can't change.
375 if (skb->pkt_type == PACKET_OTHERHOST)
376 goto abort_kfree;
378 if (sk->sk_state & PPPOX_BOUND) {
379 ppp_input(&po->chan, skb);
380 } else if (sk->sk_state & PPPOX_RELAY) {
381 relay_po = get_item_by_addr(sock_net(sk),
382 &po->pppoe_relay);
383 if (relay_po == NULL)
384 goto abort_kfree;
386 if ((sk_pppox(relay_po)->sk_state & PPPOX_CONNECTED) == 0)
387 goto abort_put;
389 if (!__pppoe_xmit(sk_pppox(relay_po), skb))
390 goto abort_put;
392 sock_put(sk_pppox(relay_po));
393 } else {
394 if (sock_queue_rcv_skb(sk, skb))
395 goto abort_kfree;
398 return NET_RX_SUCCESS;
400 abort_put:
401 sock_put(sk_pppox(relay_po));
403 abort_kfree:
404 kfree_skb(skb);
405 return NET_RX_DROP;
408 /************************************************************************
410 * Receive wrapper called in BH context.
412 ***********************************************************************/
413 static int pppoe_rcv(struct sk_buff *skb, struct net_device *dev,
414 struct packet_type *pt, struct net_device *orig_dev)
416 struct pppoe_hdr *ph;
417 struct pppox_sock *po;
418 struct pppoe_net *pn;
419 int len;
421 skb = skb_share_check(skb, GFP_ATOMIC);
422 if (!skb)
423 goto out;
425 if (skb_mac_header_len(skb) < ETH_HLEN)
426 goto drop;
428 if (!pskb_may_pull(skb, sizeof(struct pppoe_hdr)))
429 goto drop;
431 ph = pppoe_hdr(skb);
432 len = ntohs(ph->length);
434 skb_pull_rcsum(skb, sizeof(*ph));
435 if (skb->len < len)
436 goto drop;
438 if (pskb_trim_rcsum(skb, len))
439 goto drop;
441 ph = pppoe_hdr(skb);
442 pn = pppoe_pernet(dev_net(dev));
444 /* Note that get_item does a sock_hold(), so sk_pppox(po)
445 * is known to be safe.
447 po = get_item(pn, ph->sid, eth_hdr(skb)->h_source, dev->ifindex);
448 if (!po)
449 goto drop;
451 return sk_receive_skb(sk_pppox(po), skb, 0);
453 drop:
454 kfree_skb(skb);
455 out:
456 return NET_RX_DROP;
459 static void pppoe_unbind_sock_work(struct work_struct *work)
461 struct pppox_sock *po = container_of(work, struct pppox_sock,
462 proto.pppoe.padt_work);
463 struct sock *sk = sk_pppox(po);
465 lock_sock(sk);
466 if (po->pppoe_dev) {
467 dev_put(po->pppoe_dev);
468 po->pppoe_dev = NULL;
470 pppox_unbind_sock(sk);
471 release_sock(sk);
472 sock_put(sk);
475 /************************************************************************
477 * Receive a PPPoE Discovery frame.
478 * This is solely for detection of PADT frames
480 ***********************************************************************/
481 static int pppoe_disc_rcv(struct sk_buff *skb, struct net_device *dev,
482 struct packet_type *pt, struct net_device *orig_dev)
485 struct pppoe_hdr *ph;
486 struct pppox_sock *po;
487 struct pppoe_net *pn;
489 skb = skb_share_check(skb, GFP_ATOMIC);
490 if (!skb)
491 goto out;
493 if (!pskb_may_pull(skb, sizeof(struct pppoe_hdr)))
494 goto abort;
496 ph = pppoe_hdr(skb);
497 if (ph->code != PADT_CODE)
498 goto abort;
500 pn = pppoe_pernet(dev_net(dev));
501 po = get_item(pn, ph->sid, eth_hdr(skb)->h_source, dev->ifindex);
502 if (po)
503 if (!schedule_work(&po->proto.pppoe.padt_work))
504 sock_put(sk_pppox(po));
506 abort:
507 kfree_skb(skb);
508 out:
509 return NET_RX_SUCCESS; /* Lies... :-) */
512 static struct packet_type pppoes_ptype __read_mostly = {
513 .type = cpu_to_be16(ETH_P_PPP_SES),
514 .func = pppoe_rcv,
517 static struct packet_type pppoed_ptype __read_mostly = {
518 .type = cpu_to_be16(ETH_P_PPP_DISC),
519 .func = pppoe_disc_rcv,
522 static struct proto pppoe_sk_proto __read_mostly = {
523 .name = "PPPOE",
524 .owner = THIS_MODULE,
525 .obj_size = sizeof(struct pppox_sock),
528 /***********************************************************************
530 * Initialize a new struct sock.
532 **********************************************************************/
533 static int pppoe_create(struct net *net, struct socket *sock, int kern)
535 struct sock *sk;
537 sk = sk_alloc(net, PF_PPPOX, GFP_KERNEL, &pppoe_sk_proto, kern);
538 if (!sk)
539 return -ENOMEM;
541 sock_init_data(sock, sk);
543 sock->state = SS_UNCONNECTED;
544 sock->ops = &pppoe_ops;
546 sk->sk_backlog_rcv = pppoe_rcv_core;
547 sk->sk_state = PPPOX_NONE;
548 sk->sk_type = SOCK_STREAM;
549 sk->sk_family = PF_PPPOX;
550 sk->sk_protocol = PX_PROTO_OE;
552 INIT_WORK(&pppox_sk(sk)->proto.pppoe.padt_work,
553 pppoe_unbind_sock_work);
555 return 0;
558 static int pppoe_release(struct socket *sock)
560 struct sock *sk = sock->sk;
561 struct pppox_sock *po;
562 struct pppoe_net *pn;
563 struct net *net = NULL;
565 if (!sk)
566 return 0;
568 lock_sock(sk);
569 if (sock_flag(sk, SOCK_DEAD)) {
570 release_sock(sk);
571 return -EBADF;
574 po = pppox_sk(sk);
576 if (po->pppoe_dev) {
577 dev_put(po->pppoe_dev);
578 po->pppoe_dev = NULL;
581 pppox_unbind_sock(sk);
583 /* Signal the death of the socket. */
584 sk->sk_state = PPPOX_DEAD;
586 net = sock_net(sk);
587 pn = pppoe_pernet(net);
590 * protect "po" from concurrent updates
591 * on pppoe_flush_dev
593 delete_item(pn, po->pppoe_pa.sid, po->pppoe_pa.remote,
594 po->pppoe_ifindex);
596 sock_orphan(sk);
597 sock->sk = NULL;
599 skb_queue_purge(&sk->sk_receive_queue);
600 release_sock(sk);
601 sock_put(sk);
603 return 0;
606 static int pppoe_connect(struct socket *sock, struct sockaddr *uservaddr,
607 int sockaddr_len, int flags)
609 struct sock *sk = sock->sk;
610 struct sockaddr_pppox *sp = (struct sockaddr_pppox *)uservaddr;
611 struct pppox_sock *po = pppox_sk(sk);
612 struct net_device *dev = NULL;
613 struct pppoe_net *pn;
614 struct net *net = NULL;
615 int error;
617 lock_sock(sk);
619 error = -EINVAL;
621 if (sockaddr_len != sizeof(struct sockaddr_pppox))
622 goto end;
624 if (sp->sa_protocol != PX_PROTO_OE)
625 goto end;
627 /* Check for already bound sockets */
628 error = -EBUSY;
629 if ((sk->sk_state & PPPOX_CONNECTED) &&
630 stage_session(sp->sa_addr.pppoe.sid))
631 goto end;
633 /* Check for already disconnected sockets, on attempts to disconnect */
634 error = -EALREADY;
635 if ((sk->sk_state & PPPOX_DEAD) &&
636 !stage_session(sp->sa_addr.pppoe.sid))
637 goto end;
639 error = 0;
641 /* Delete the old binding */
642 if (stage_session(po->pppoe_pa.sid)) {
643 pppox_unbind_sock(sk);
644 pn = pppoe_pernet(sock_net(sk));
645 delete_item(pn, po->pppoe_pa.sid,
646 po->pppoe_pa.remote, po->pppoe_ifindex);
647 if (po->pppoe_dev) {
648 dev_put(po->pppoe_dev);
649 po->pppoe_dev = NULL;
652 po->pppoe_ifindex = 0;
653 memset(&po->pppoe_pa, 0, sizeof(po->pppoe_pa));
654 memset(&po->pppoe_relay, 0, sizeof(po->pppoe_relay));
655 memset(&po->chan, 0, sizeof(po->chan));
656 po->next = NULL;
657 po->num = 0;
659 sk->sk_state = PPPOX_NONE;
662 /* Re-bind in session stage only */
663 if (stage_session(sp->sa_addr.pppoe.sid)) {
664 error = -ENODEV;
665 net = sock_net(sk);
666 dev = dev_get_by_name(net, sp->sa_addr.pppoe.dev);
667 if (!dev)
668 goto err_put;
670 po->pppoe_dev = dev;
671 po->pppoe_ifindex = dev->ifindex;
672 pn = pppoe_pernet(net);
673 if (!(dev->flags & IFF_UP)) {
674 goto err_put;
677 memcpy(&po->pppoe_pa,
678 &sp->sa_addr.pppoe,
679 sizeof(struct pppoe_addr));
681 write_lock_bh(&pn->hash_lock);
682 error = __set_item(pn, po);
683 write_unlock_bh(&pn->hash_lock);
684 if (error < 0)
685 goto err_put;
687 po->chan.hdrlen = (sizeof(struct pppoe_hdr) +
688 dev->hard_header_len);
690 po->chan.mtu = dev->mtu - sizeof(struct pppoe_hdr) - 2;
691 po->chan.private = sk;
692 po->chan.ops = &pppoe_chan_ops;
694 error = ppp_register_net_channel(dev_net(dev), &po->chan);
695 if (error) {
696 delete_item(pn, po->pppoe_pa.sid,
697 po->pppoe_pa.remote, po->pppoe_ifindex);
698 goto err_put;
701 sk->sk_state = PPPOX_CONNECTED;
704 po->num = sp->sa_addr.pppoe.sid;
706 end:
707 release_sock(sk);
708 return error;
709 err_put:
710 if (po->pppoe_dev) {
711 dev_put(po->pppoe_dev);
712 po->pppoe_dev = NULL;
714 goto end;
717 static int pppoe_getname(struct socket *sock, struct sockaddr *uaddr,
718 int peer)
720 int len = sizeof(struct sockaddr_pppox);
721 struct sockaddr_pppox sp;
723 sp.sa_family = AF_PPPOX;
724 sp.sa_protocol = PX_PROTO_OE;
725 memcpy(&sp.sa_addr.pppoe, &pppox_sk(sock->sk)->pppoe_pa,
726 sizeof(struct pppoe_addr));
728 memcpy(uaddr, &sp, len);
730 return len;
733 static int pppoe_ioctl(struct socket *sock, unsigned int cmd,
734 unsigned long arg)
736 struct sock *sk = sock->sk;
737 struct pppox_sock *po = pppox_sk(sk);
738 int val;
739 int err;
741 switch (cmd) {
742 case PPPIOCGMRU:
743 err = -ENXIO;
744 if (!(sk->sk_state & PPPOX_CONNECTED))
745 break;
747 err = -EFAULT;
748 if (put_user(po->pppoe_dev->mtu -
749 sizeof(struct pppoe_hdr) -
750 PPP_HDRLEN,
751 (int __user *)arg))
752 break;
753 err = 0;
754 break;
756 case PPPIOCSMRU:
757 err = -ENXIO;
758 if (!(sk->sk_state & PPPOX_CONNECTED))
759 break;
761 err = -EFAULT;
762 if (get_user(val, (int __user *)arg))
763 break;
765 if (val < (po->pppoe_dev->mtu
766 - sizeof(struct pppoe_hdr)
767 - PPP_HDRLEN))
768 err = 0;
769 else
770 err = -EINVAL;
771 break;
773 case PPPIOCSFLAGS:
774 err = -EFAULT;
775 if (get_user(val, (int __user *)arg))
776 break;
777 err = 0;
778 break;
780 case PPPOEIOCSFWD:
782 struct pppox_sock *relay_po;
784 err = -EBUSY;
785 if (sk->sk_state & (PPPOX_BOUND | PPPOX_DEAD))
786 break;
788 err = -ENOTCONN;
789 if (!(sk->sk_state & PPPOX_CONNECTED))
790 break;
792 /* PPPoE address from the user specifies an outbound
793 PPPoE address which frames are forwarded to */
794 err = -EFAULT;
795 if (copy_from_user(&po->pppoe_relay,
796 (void __user *)arg,
797 sizeof(struct sockaddr_pppox)))
798 break;
800 err = -EINVAL;
801 if (po->pppoe_relay.sa_family != AF_PPPOX ||
802 po->pppoe_relay.sa_protocol != PX_PROTO_OE)
803 break;
805 /* Check that the socket referenced by the address
806 actually exists. */
807 relay_po = get_item_by_addr(sock_net(sk), &po->pppoe_relay);
808 if (!relay_po)
809 break;
811 sock_put(sk_pppox(relay_po));
812 sk->sk_state |= PPPOX_RELAY;
813 err = 0;
814 break;
817 case PPPOEIOCDFWD:
818 err = -EALREADY;
819 if (!(sk->sk_state & PPPOX_RELAY))
820 break;
822 sk->sk_state &= ~PPPOX_RELAY;
823 err = 0;
824 break;
826 default:
827 err = -ENOTTY;
830 return err;
833 static int pppoe_sendmsg(struct socket *sock, struct msghdr *m,
834 size_t total_len)
836 struct sk_buff *skb;
837 struct sock *sk = sock->sk;
838 struct pppox_sock *po = pppox_sk(sk);
839 int error;
840 struct pppoe_hdr hdr;
841 struct pppoe_hdr *ph;
842 struct net_device *dev;
843 char *start;
844 int hlen;
846 lock_sock(sk);
847 if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED)) {
848 error = -ENOTCONN;
849 goto end;
852 hdr.ver = 1;
853 hdr.type = 1;
854 hdr.code = 0;
855 hdr.sid = po->num;
857 dev = po->pppoe_dev;
859 error = -EMSGSIZE;
860 if (total_len > (dev->mtu + dev->hard_header_len))
861 goto end;
863 hlen = LL_RESERVED_SPACE(dev);
864 skb = sock_wmalloc(sk, hlen + sizeof(*ph) + total_len +
865 dev->needed_tailroom, 0, GFP_KERNEL);
866 if (!skb) {
867 error = -ENOMEM;
868 goto end;
871 /* Reserve space for headers. */
872 skb_reserve(skb, hlen);
873 skb_reset_network_header(skb);
875 skb->dev = dev;
877 skb->priority = sk->sk_priority;
878 skb->protocol = cpu_to_be16(ETH_P_PPP_SES);
880 ph = skb_put(skb, total_len + sizeof(struct pppoe_hdr));
881 start = (char *)&ph->tag[0];
883 error = memcpy_from_msg(start, m, total_len);
884 if (error < 0) {
885 kfree_skb(skb);
886 goto end;
889 error = total_len;
890 dev_hard_header(skb, dev, ETH_P_PPP_SES,
891 po->pppoe_pa.remote, NULL, total_len);
893 memcpy(ph, &hdr, sizeof(struct pppoe_hdr));
895 ph->length = htons(total_len);
897 dev_queue_xmit(skb);
899 end:
900 release_sock(sk);
901 return error;
904 /************************************************************************
906 * xmit function for internal use.
908 ***********************************************************************/
909 static int __pppoe_xmit(struct sock *sk, struct sk_buff *skb)
911 struct pppox_sock *po = pppox_sk(sk);
912 struct net_device *dev = po->pppoe_dev;
913 struct pppoe_hdr *ph;
914 int data_len = skb->len;
916 /* The higher-level PPP code (ppp_unregister_channel()) ensures the PPP
917 * xmit operations conclude prior to an unregistration call. Thus
918 * sk->sk_state cannot change, so we don't need to do lock_sock().
919 * But, we also can't do a lock_sock since that introduces a potential
920 * deadlock as we'd reverse the lock ordering used when calling
921 * ppp_unregister_channel().
924 if (sock_flag(sk, SOCK_DEAD) || !(sk->sk_state & PPPOX_CONNECTED))
925 goto abort;
927 if (!dev)
928 goto abort;
930 /* Copy the data if there is no space for the header or if it's
931 * read-only.
933 if (skb_cow_head(skb, LL_RESERVED_SPACE(dev) + sizeof(*ph)))
934 goto abort;
936 __skb_push(skb, sizeof(*ph));
937 skb_reset_network_header(skb);
939 ph = pppoe_hdr(skb);
940 ph->ver = 1;
941 ph->type = 1;
942 ph->code = 0;
943 ph->sid = po->num;
944 ph->length = htons(data_len);
946 skb->protocol = cpu_to_be16(ETH_P_PPP_SES);
947 skb->dev = dev;
949 dev_hard_header(skb, dev, ETH_P_PPP_SES,
950 po->pppoe_pa.remote, NULL, data_len);
952 dev_queue_xmit(skb);
953 return 1;
955 abort:
956 kfree_skb(skb);
957 return 1;
960 /************************************************************************
962 * xmit function called by generic PPP driver
963 * sends PPP frame over PPPoE socket
965 ***********************************************************************/
966 static int pppoe_xmit(struct ppp_channel *chan, struct sk_buff *skb)
968 struct sock *sk = (struct sock *)chan->private;
969 return __pppoe_xmit(sk, skb);
972 static const struct ppp_channel_ops pppoe_chan_ops = {
973 .start_xmit = pppoe_xmit,
976 static int pppoe_recvmsg(struct socket *sock, struct msghdr *m,
977 size_t total_len, int flags)
979 struct sock *sk = sock->sk;
980 struct sk_buff *skb;
981 int error = 0;
983 if (sk->sk_state & PPPOX_BOUND) {
984 error = -EIO;
985 goto end;
988 skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
989 flags & MSG_DONTWAIT, &error);
990 if (error < 0)
991 goto end;
993 if (skb) {
994 total_len = min_t(size_t, total_len, skb->len);
995 error = skb_copy_datagram_msg(skb, 0, m, total_len);
996 if (error == 0) {
997 consume_skb(skb);
998 return total_len;
1002 kfree_skb(skb);
1003 end:
1004 return error;
1007 #ifdef CONFIG_PROC_FS
1008 static int pppoe_seq_show(struct seq_file *seq, void *v)
1010 struct pppox_sock *po;
1011 char *dev_name;
1013 if (v == SEQ_START_TOKEN) {
1014 seq_puts(seq, "Id Address Device\n");
1015 goto out;
1018 po = v;
1019 dev_name = po->pppoe_pa.dev;
1021 seq_printf(seq, "%08X %pM %8s\n",
1022 po->pppoe_pa.sid, po->pppoe_pa.remote, dev_name);
1023 out:
1024 return 0;
1027 static inline struct pppox_sock *pppoe_get_idx(struct pppoe_net *pn, loff_t pos)
1029 struct pppox_sock *po;
1030 int i;
1032 for (i = 0; i < PPPOE_HASH_SIZE; i++) {
1033 po = pn->hash_table[i];
1034 while (po) {
1035 if (!pos--)
1036 goto out;
1037 po = po->next;
1041 out:
1042 return po;
1045 static void *pppoe_seq_start(struct seq_file *seq, loff_t *pos)
1046 __acquires(pn->hash_lock)
1048 struct pppoe_net *pn = pppoe_pernet(seq_file_net(seq));
1049 loff_t l = *pos;
1051 read_lock_bh(&pn->hash_lock);
1052 return l ? pppoe_get_idx(pn, --l) : SEQ_START_TOKEN;
1055 static void *pppoe_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1057 struct pppoe_net *pn = pppoe_pernet(seq_file_net(seq));
1058 struct pppox_sock *po;
1060 ++*pos;
1061 if (v == SEQ_START_TOKEN) {
1062 po = pppoe_get_idx(pn, 0);
1063 goto out;
1065 po = v;
1066 if (po->next)
1067 po = po->next;
1068 else {
1069 int hash = hash_item(po->pppoe_pa.sid, po->pppoe_pa.remote);
1071 po = NULL;
1072 while (++hash < PPPOE_HASH_SIZE) {
1073 po = pn->hash_table[hash];
1074 if (po)
1075 break;
1079 out:
1080 return po;
1083 static void pppoe_seq_stop(struct seq_file *seq, void *v)
1084 __releases(pn->hash_lock)
1086 struct pppoe_net *pn = pppoe_pernet(seq_file_net(seq));
1087 read_unlock_bh(&pn->hash_lock);
1090 static const struct seq_operations pppoe_seq_ops = {
1091 .start = pppoe_seq_start,
1092 .next = pppoe_seq_next,
1093 .stop = pppoe_seq_stop,
1094 .show = pppoe_seq_show,
1096 #endif /* CONFIG_PROC_FS */
1098 static const struct proto_ops pppoe_ops = {
1099 .family = AF_PPPOX,
1100 .owner = THIS_MODULE,
1101 .release = pppoe_release,
1102 .bind = sock_no_bind,
1103 .connect = pppoe_connect,
1104 .socketpair = sock_no_socketpair,
1105 .accept = sock_no_accept,
1106 .getname = pppoe_getname,
1107 .poll = datagram_poll,
1108 .listen = sock_no_listen,
1109 .shutdown = sock_no_shutdown,
1110 .setsockopt = sock_no_setsockopt,
1111 .getsockopt = sock_no_getsockopt,
1112 .sendmsg = pppoe_sendmsg,
1113 .recvmsg = pppoe_recvmsg,
1114 .mmap = sock_no_mmap,
1115 .ioctl = pppox_ioctl,
1116 #ifdef CONFIG_COMPAT
1117 .compat_ioctl = pppox_compat_ioctl,
1118 #endif
1121 static const struct pppox_proto pppoe_proto = {
1122 .create = pppoe_create,
1123 .ioctl = pppoe_ioctl,
1124 .owner = THIS_MODULE,
1127 static __net_init int pppoe_init_net(struct net *net)
1129 struct pppoe_net *pn = pppoe_pernet(net);
1130 struct proc_dir_entry *pde;
1132 rwlock_init(&pn->hash_lock);
1134 pde = proc_create_net("pppoe", 0444, net->proc_net,
1135 &pppoe_seq_ops, sizeof(struct seq_net_private));
1136 #ifdef CONFIG_PROC_FS
1137 if (!pde)
1138 return -ENOMEM;
1139 #endif
1141 return 0;
1144 static __net_exit void pppoe_exit_net(struct net *net)
1146 remove_proc_entry("pppoe", net->proc_net);
1149 static struct pernet_operations pppoe_net_ops = {
1150 .init = pppoe_init_net,
1151 .exit = pppoe_exit_net,
1152 .id = &pppoe_net_id,
1153 .size = sizeof(struct pppoe_net),
1156 static int __init pppoe_init(void)
1158 int err;
1160 err = register_pernet_device(&pppoe_net_ops);
1161 if (err)
1162 goto out;
1164 err = proto_register(&pppoe_sk_proto, 0);
1165 if (err)
1166 goto out_unregister_net_ops;
1168 err = register_pppox_proto(PX_PROTO_OE, &pppoe_proto);
1169 if (err)
1170 goto out_unregister_pppoe_proto;
1172 dev_add_pack(&pppoes_ptype);
1173 dev_add_pack(&pppoed_ptype);
1174 register_netdevice_notifier(&pppoe_notifier);
1176 return 0;
1178 out_unregister_pppoe_proto:
1179 proto_unregister(&pppoe_sk_proto);
1180 out_unregister_net_ops:
1181 unregister_pernet_device(&pppoe_net_ops);
1182 out:
1183 return err;
1186 static void __exit pppoe_exit(void)
1188 unregister_netdevice_notifier(&pppoe_notifier);
1189 dev_remove_pack(&pppoed_ptype);
1190 dev_remove_pack(&pppoes_ptype);
1191 unregister_pppox_proto(PX_PROTO_OE);
1192 proto_unregister(&pppoe_sk_proto);
1193 unregister_pernet_device(&pppoe_net_ops);
1196 module_init(pppoe_init);
1197 module_exit(pppoe_exit);
1199 MODULE_AUTHOR("Michal Ostrowski <mostrows@speakeasy.net>");
1200 MODULE_DESCRIPTION("PPP over Ethernet driver");
1201 MODULE_LICENSE("GPL");
1202 MODULE_ALIAS_NET_PF_PROTO(PF_PPPOX, PX_PROTO_OE);