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include: replace linux/module.h with "struct module" wherever possible
[linux-2.6/next.git] / drivers / net / pptp.c
blobeae542a7e987e6e4dd4a54f3d7cb127f3766fc47
1 /*
2 * Point-to-Point Tunneling Protocol for Linux
3 *
4 * Authors: Dmitry Kozlov <xeb@mail.ru>
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 *
11 */
12
13 #include <linux/string.h>
14 #include <linux/module.h>
15 #include <linux/kernel.h>
16 #include <linux/slab.h>
17 #include <linux/errno.h>
18 #include <linux/netdevice.h>
19 #include <linux/net.h>
20 #include <linux/skbuff.h>
21 #include <linux/vmalloc.h>
22 #include <linux/init.h>
23 #include <linux/ppp_channel.h>
24 #include <linux/ppp_defs.h>
25 #include <linux/if_pppox.h>
26 #include <linux/if_ppp.h>
27 #include <linux/notifier.h>
28 #include <linux/file.h>
29 #include <linux/in.h>
30 #include <linux/ip.h>
31 #include <linux/netfilter.h>
32 #include <linux/netfilter_ipv4.h>
33 #include <linux/rcupdate.h>
34 #include <linux/spinlock.h>
35
36 #include <net/sock.h>
37 #include <net/protocol.h>
38 #include <net/ip.h>
39 #include <net/icmp.h>
40 #include <net/route.h>
41 #include <net/gre.h>
42
43 #include <linux/uaccess.h>
44
45 #define PPTP_DRIVER_VERSION "0.8.5"
46
47 #define MAX_CALLID 65535
48
49 static DECLARE_BITMAP(callid_bitmap, MAX_CALLID + 1);
50 static struct pppox_sock **callid_sock;
51
52 static DEFINE_SPINLOCK(chan_lock);
53
54 static struct proto pptp_sk_proto __read_mostly;
55 static const struct ppp_channel_ops pptp_chan_ops;
56 static const struct proto_ops pptp_ops;
57
58 #define PPP_LCP_ECHOREQ 0x09
59 #define PPP_LCP_ECHOREP 0x0A
60 #define SC_RCV_BITS (SC_RCV_B7_1|SC_RCV_B7_0|SC_RCV_ODDP|SC_RCV_EVNP)
61
62 #define MISSING_WINDOW 20
63 #define WRAPPED(curseq, lastseq)\
64 ((((curseq) & 0xffffff00) == 0) &&\
65 (((lastseq) & 0xffffff00) == 0xffffff00))
66
67 #define PPTP_GRE_PROTO 0x880B
68 #define PPTP_GRE_VER 0x1
69
70 #define PPTP_GRE_FLAG_C 0x80
71 #define PPTP_GRE_FLAG_R 0x40
72 #define PPTP_GRE_FLAG_K 0x20
73 #define PPTP_GRE_FLAG_S 0x10
74 #define PPTP_GRE_FLAG_A 0x80
75
76 #define PPTP_GRE_IS_C(f) ((f)&PPTP_GRE_FLAG_C)
77 #define PPTP_GRE_IS_R(f) ((f)&PPTP_GRE_FLAG_R)
78 #define PPTP_GRE_IS_K(f) ((f)&PPTP_GRE_FLAG_K)
79 #define PPTP_GRE_IS_S(f) ((f)&PPTP_GRE_FLAG_S)
80 #define PPTP_GRE_IS_A(f) ((f)&PPTP_GRE_FLAG_A)
81
82 #define PPTP_HEADER_OVERHEAD (2+sizeof(struct pptp_gre_header))
83 struct pptp_gre_header {
84 u8 flags;
85 u8 ver;
86 u16 protocol;
87 u16 payload_len;
88 u16 call_id;
89 u32 seq;
90 u32 ack;
91 } __packed;
92
93 static struct pppox_sock *lookup_chan(u16 call_id, __be32 s_addr)
94 {
95 struct pppox_sock *sock;
96 struct pptp_opt *opt;
97
98 rcu_read_lock();
99 sock = rcu_dereference(callid_sock[call_id]);
100 if (sock) {
101 opt = &sock->proto.pptp;
102 if (opt->dst_addr.sin_addr.s_addr != s_addr)
103 sock = NULL;
104 else
105 sock_hold(sk_pppox(sock));
106 }
107 rcu_read_unlock();
108
109 return sock;
110 }
111
112 static int lookup_chan_dst(u16 call_id, __be32 d_addr)
113 {
114 struct pppox_sock *sock;
115 struct pptp_opt *opt;
116 int i;
117
118 rcu_read_lock();
119 for (i = find_next_bit(callid_bitmap, MAX_CALLID, 1); i < MAX_CALLID;
120 i = find_next_bit(callid_bitmap, MAX_CALLID, i + 1)) {
121 sock = rcu_dereference(callid_sock[i]);
122 if (!sock)
123 continue;
124 opt = &sock->proto.pptp;
125 if (opt->dst_addr.call_id == call_id &&
126 opt->dst_addr.sin_addr.s_addr == d_addr)
127 break;
128 }
129 rcu_read_unlock();
130
131 return i < MAX_CALLID;
132 }
133
134 static int add_chan(struct pppox_sock *sock)
135 {
136 static int call_id;
137
138 spin_lock(&chan_lock);
139 if (!sock->proto.pptp.src_addr.call_id) {
140 call_id = find_next_zero_bit(callid_bitmap, MAX_CALLID, call_id + 1);
141 if (call_id == MAX_CALLID) {
142 call_id = find_next_zero_bit(callid_bitmap, MAX_CALLID, 1);
143 if (call_id == MAX_CALLID)
144 goto out_err;
145 }
146 sock->proto.pptp.src_addr.call_id = call_id;
147 } else if (test_bit(sock->proto.pptp.src_addr.call_id, callid_bitmap))
148 goto out_err;
149
150 set_bit(sock->proto.pptp.src_addr.call_id, callid_bitmap);
151 rcu_assign_pointer(callid_sock[sock->proto.pptp.src_addr.call_id], sock);
152 spin_unlock(&chan_lock);
153
154 return 0;
155
156 out_err:
157 spin_unlock(&chan_lock);
158 return -1;
159 }
160
161 static void del_chan(struct pppox_sock *sock)
162 {
163 spin_lock(&chan_lock);
164 clear_bit(sock->proto.pptp.src_addr.call_id, callid_bitmap);
165 rcu_assign_pointer(callid_sock[sock->proto.pptp.src_addr.call_id], NULL);
166 spin_unlock(&chan_lock);
167 synchronize_rcu();
168 }
169
170 static int pptp_xmit(struct ppp_channel *chan, struct sk_buff *skb)
171 {
172 struct sock *sk = (struct sock *) chan->private;
173 struct pppox_sock *po = pppox_sk(sk);
174 struct pptp_opt *opt = &po->proto.pptp;
175 struct pptp_gre_header *hdr;
176 unsigned int header_len = sizeof(*hdr);
177 struct flowi4 fl4;
178 int islcp;
179 int len;
180 unsigned char *data;
181 __u32 seq_recv;
182
183
184 struct rtable *rt;
185 struct net_device *tdev;
186 struct iphdr *iph;
187 int max_headroom;
188
189 if (sk_pppox(po)->sk_state & PPPOX_DEAD)
190 goto tx_error;
191
192 rt = ip_route_output_ports(&init_net, &fl4, NULL,
193 opt->dst_addr.sin_addr.s_addr,
194 opt->src_addr.sin_addr.s_addr,
195 0, 0, IPPROTO_GRE,
196 RT_TOS(0), 0);
197 if (IS_ERR(rt))
198 goto tx_error;
199
200 tdev = rt->dst.dev;
201
202 max_headroom = LL_RESERVED_SPACE(tdev) + sizeof(*iph) + sizeof(*hdr) + 2;
203
204 if (skb_headroom(skb) < max_headroom || skb_cloned(skb) || skb_shared(skb)) {
205 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
206 if (!new_skb) {
207 ip_rt_put(rt);
208 goto tx_error;
209 }
210 if (skb->sk)
211 skb_set_owner_w(new_skb, skb->sk);
212 kfree_skb(skb);
213 skb = new_skb;
214 }
215
216 data = skb->data;
217 islcp = ((data[0] << 8) + data[1]) == PPP_LCP && 1 <= data[2] && data[2] <= 7;
218
219 /* compress protocol field */
220 if ((opt->ppp_flags & SC_COMP_PROT) && data[0] == 0 && !islcp)
221 skb_pull(skb, 1);
222
223 /* Put in the address/control bytes if necessary */
224 if ((opt->ppp_flags & SC_COMP_AC) == 0 || islcp) {
225 data = skb_push(skb, 2);
226 data[0] = PPP_ALLSTATIONS;
227 data[1] = PPP_UI;
228 }
229
230 len = skb->len;
231
232 seq_recv = opt->seq_recv;
233
234 if (opt->ack_sent == seq_recv)
235 header_len -= sizeof(hdr->ack);
236
237 /* Push down and install GRE header */
238 skb_push(skb, header_len);
239 hdr = (struct pptp_gre_header *)(skb->data);
240
241 hdr->flags = PPTP_GRE_FLAG_K;
242 hdr->ver = PPTP_GRE_VER;
243 hdr->protocol = htons(PPTP_GRE_PROTO);
244 hdr->call_id = htons(opt->dst_addr.call_id);
245
246 hdr->flags |= PPTP_GRE_FLAG_S;
247 hdr->seq = htonl(++opt->seq_sent);
248 if (opt->ack_sent != seq_recv) {
249 /* send ack with this message */
250 hdr->ver |= PPTP_GRE_FLAG_A;
251 hdr->ack = htonl(seq_recv);
252 opt->ack_sent = seq_recv;
253 }
254 hdr->payload_len = htons(len);
255
256 /* Push down and install the IP header. */
257
258 skb_reset_transport_header(skb);
259 skb_push(skb, sizeof(*iph));
260 skb_reset_network_header(skb);
261 memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
262 IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED | IPSKB_REROUTED);
263
264 iph = ip_hdr(skb);
265 iph->version = 4;
266 iph->ihl = sizeof(struct iphdr) >> 2;
267 if (ip_dont_fragment(sk, &rt->dst))
268 iph->frag_off = htons(IP_DF);
269 else
270 iph->frag_off = 0;
271 iph->protocol = IPPROTO_GRE;
272 iph->tos = 0;
273 iph->daddr = fl4.daddr;
274 iph->saddr = fl4.saddr;
275 iph->ttl = ip4_dst_hoplimit(&rt->dst);
276 iph->tot_len = htons(skb->len);
277
278 skb_dst_drop(skb);
279 skb_dst_set(skb, &rt->dst);
280
281 nf_reset(skb);
282
283 skb->ip_summed = CHECKSUM_NONE;
284 ip_select_ident(iph, &rt->dst, NULL);
285 ip_send_check(iph);
286
287 ip_local_out(skb);
288
289 tx_error:
290 return 1;
291 }
292
293 static int pptp_rcv_core(struct sock *sk, struct sk_buff *skb)
294 {
295 struct pppox_sock *po = pppox_sk(sk);
296 struct pptp_opt *opt = &po->proto.pptp;
297 int headersize, payload_len, seq;
298 __u8 *payload;
299 struct pptp_gre_header *header;
300
301 if (!(sk->sk_state & PPPOX_CONNECTED)) {
302 if (sock_queue_rcv_skb(sk, skb))
303 goto drop;
304 return NET_RX_SUCCESS;
305 }
306
307 header = (struct pptp_gre_header *)(skb->data);
308
309 /* test if acknowledgement present */
310 if (PPTP_GRE_IS_A(header->ver)) {
311 __u32 ack = (PPTP_GRE_IS_S(header->flags)) ?
312 header->ack : header->seq; /* ack in different place if S = 0 */
313
314 ack = ntohl(ack);
315
316 if (ack > opt->ack_recv)
317 opt->ack_recv = ack;
318 /* also handle sequence number wrap-around */
319 if (WRAPPED(ack, opt->ack_recv))
320 opt->ack_recv = ack;
321 }
322
323 /* test if payload present */
324 if (!PPTP_GRE_IS_S(header->flags))
325 goto drop;
326
327 headersize = sizeof(*header);
328 payload_len = ntohs(header->payload_len);
329 seq = ntohl(header->seq);
330
331 /* no ack present? */
332 if (!PPTP_GRE_IS_A(header->ver))
333 headersize -= sizeof(header->ack);
334 /* check for incomplete packet (length smaller than expected) */
335 if (skb->len - headersize < payload_len)
336 goto drop;
337
338 payload = skb->data + headersize;
339 /* check for expected sequence number */
340 if (seq < opt->seq_recv + 1 || WRAPPED(opt->seq_recv, seq)) {
341 if ((payload[0] == PPP_ALLSTATIONS) && (payload[1] == PPP_UI) &&
342 (PPP_PROTOCOL(payload) == PPP_LCP) &&
343 ((payload[4] == PPP_LCP_ECHOREQ) || (payload[4] == PPP_LCP_ECHOREP)))
344 goto allow_packet;
345 } else {
346 opt->seq_recv = seq;
347 allow_packet:
348 skb_pull(skb, headersize);
349
350 if (payload[0] == PPP_ALLSTATIONS && payload[1] == PPP_UI) {
351 /* chop off address/control */
352 if (skb->len < 3)
353 goto drop;
354 skb_pull(skb, 2);
355 }
356
357 if ((*skb->data) & 1) {
358 /* protocol is compressed */
359 skb_push(skb, 1)[0] = 0;
360 }
361
362 skb->ip_summed = CHECKSUM_NONE;
363 skb_set_network_header(skb, skb->head-skb->data);
364 ppp_input(&po->chan, skb);
365
366 return NET_RX_SUCCESS;
367 }
368 drop:
369 kfree_skb(skb);
370 return NET_RX_DROP;
371 }
372
373 static int pptp_rcv(struct sk_buff *skb)
374 {
375 struct pppox_sock *po;
376 struct pptp_gre_header *header;
377 struct iphdr *iph;
378
379 if (skb->pkt_type != PACKET_HOST)
380 goto drop;
381
382 if (!pskb_may_pull(skb, 12))
383 goto drop;
384
385 iph = ip_hdr(skb);
386
387 header = (struct pptp_gre_header *)skb->data;
388
389 if (ntohs(header->protocol) != PPTP_GRE_PROTO || /* PPTP-GRE protocol for PPTP */
390 PPTP_GRE_IS_C(header->flags) || /* flag C should be clear */
391 PPTP_GRE_IS_R(header->flags) || /* flag R should be clear */
392 !PPTP_GRE_IS_K(header->flags) || /* flag K should be set */
393 (header->flags&0xF) != 0) /* routing and recursion ctrl = 0 */
394 /* if invalid, discard this packet */
395 goto drop;
396
397 po = lookup_chan(htons(header->call_id), iph->saddr);
398 if (po) {
399 skb_dst_drop(skb);
400 nf_reset(skb);
401 return sk_receive_skb(sk_pppox(po), skb, 0);
402 }
403 drop:
404 kfree_skb(skb);
405 return NET_RX_DROP;
406 }
407
408 static int pptp_bind(struct socket *sock, struct sockaddr *uservaddr,
409 int sockaddr_len)
410 {
411 struct sock *sk = sock->sk;
412 struct sockaddr_pppox *sp = (struct sockaddr_pppox *) uservaddr;
413 struct pppox_sock *po = pppox_sk(sk);
414 struct pptp_opt *opt = &po->proto.pptp;
415 int error = 0;
416
417 lock_sock(sk);
418
419 opt->src_addr = sp->sa_addr.pptp;
420 if (add_chan(po)) {
421 release_sock(sk);
422 error = -EBUSY;
423 }
424
425 release_sock(sk);
426 return error;
427 }
428
429 static int pptp_connect(struct socket *sock, struct sockaddr *uservaddr,
430 int sockaddr_len, int flags)
431 {
432 struct sock *sk = sock->sk;
433 struct sockaddr_pppox *sp = (struct sockaddr_pppox *) uservaddr;
434 struct pppox_sock *po = pppox_sk(sk);
435 struct pptp_opt *opt = &po->proto.pptp;
436 struct rtable *rt;
437 struct flowi4 fl4;
438 int error = 0;
439
440 if (sp->sa_protocol != PX_PROTO_PPTP)
441 return -EINVAL;
442
443 if (lookup_chan_dst(sp->sa_addr.pptp.call_id, sp->sa_addr.pptp.sin_addr.s_addr))
444 return -EALREADY;
445
446 lock_sock(sk);
447 /* Check for already bound sockets */
448 if (sk->sk_state & PPPOX_CONNECTED) {
449 error = -EBUSY;
450 goto end;
451 }
452
453 /* Check for already disconnected sockets, on attempts to disconnect */
454 if (sk->sk_state & PPPOX_DEAD) {
455 error = -EALREADY;
456 goto end;
457 }
458
459 if (!opt->src_addr.sin_addr.s_addr || !sp->sa_addr.pptp.sin_addr.s_addr) {
460 error = -EINVAL;
461 goto end;
462 }
463
464 po->chan.private = sk;
465 po->chan.ops = &pptp_chan_ops;
466
467 rt = ip_route_output_ports(&init_net, &fl4, sk,
468 opt->dst_addr.sin_addr.s_addr,
469 opt->src_addr.sin_addr.s_addr,
470 0, 0,
471 IPPROTO_GRE, RT_CONN_FLAGS(sk), 0);
472 if (IS_ERR(rt)) {
473 error = -EHOSTUNREACH;
474 goto end;
475 }
476 sk_setup_caps(sk, &rt->dst);
477
478 po->chan.mtu = dst_mtu(&rt->dst);
479 if (!po->chan.mtu)
480 po->chan.mtu = PPP_MTU;
481 ip_rt_put(rt);
482 po->chan.mtu -= PPTP_HEADER_OVERHEAD;
483
484 po->chan.hdrlen = 2 + sizeof(struct pptp_gre_header);
485 error = ppp_register_channel(&po->chan);
486 if (error) {
487 pr_err("PPTP: failed to register PPP channel (%d)\n", error);
488 goto end;
489 }
490
491 opt->dst_addr = sp->sa_addr.pptp;
492 sk->sk_state = PPPOX_CONNECTED;
493
494 end:
495 release_sock(sk);
496 return error;
497 }
498
499 static int pptp_getname(struct socket *sock, struct sockaddr *uaddr,
500 int *usockaddr_len, int peer)
501 {
502 int len = sizeof(struct sockaddr_pppox);
503 struct sockaddr_pppox sp;
504
505 sp.sa_family = AF_PPPOX;
506 sp.sa_protocol = PX_PROTO_PPTP;
507 sp.sa_addr.pptp = pppox_sk(sock->sk)->proto.pptp.src_addr;
508
509 memcpy(uaddr, &sp, len);
510
511 *usockaddr_len = len;
512
513 return 0;
514 }
515
516 static int pptp_release(struct socket *sock)
517 {
518 struct sock *sk = sock->sk;
519 struct pppox_sock *po;
520 struct pptp_opt *opt;
521 int error = 0;
522
523 if (!sk)
524 return 0;
525
526 lock_sock(sk);
527
528 if (sock_flag(sk, SOCK_DEAD)) {
529 release_sock(sk);
530 return -EBADF;
531 }
532
533 po = pppox_sk(sk);
534 opt = &po->proto.pptp;
535 del_chan(po);
536
537 pppox_unbind_sock(sk);
538 sk->sk_state = PPPOX_DEAD;
539
540 sock_orphan(sk);
541 sock->sk = NULL;
542
543 release_sock(sk);
544 sock_put(sk);
545
546 return error;
547 }
548
549 static void pptp_sock_destruct(struct sock *sk)
550 {
551 if (!(sk->sk_state & PPPOX_DEAD)) {
552 del_chan(pppox_sk(sk));
553 pppox_unbind_sock(sk);
554 }
555 skb_queue_purge(&sk->sk_receive_queue);
556 }
557
558 static int pptp_create(struct net *net, struct socket *sock)
559 {
560 int error = -ENOMEM;
561 struct sock *sk;
562 struct pppox_sock *po;
563 struct pptp_opt *opt;
564
565 sk = sk_alloc(net, PF_PPPOX, GFP_KERNEL, &pptp_sk_proto);
566 if (!sk)
567 goto out;
568
569 sock_init_data(sock, sk);
570
571 sock->state = SS_UNCONNECTED;
572 sock->ops = &pptp_ops;
573
574 sk->sk_backlog_rcv = pptp_rcv_core;
575 sk->sk_state = PPPOX_NONE;
576 sk->sk_type = SOCK_STREAM;
577 sk->sk_family = PF_PPPOX;
578 sk->sk_protocol = PX_PROTO_PPTP;
579 sk->sk_destruct = pptp_sock_destruct;
580
581 po = pppox_sk(sk);
582 opt = &po->proto.pptp;
583
584 opt->seq_sent = 0; opt->seq_recv = 0;
585 opt->ack_recv = 0; opt->ack_sent = 0;
586
587 error = 0;
588 out:
589 return error;
590 }
591
592 static int pptp_ppp_ioctl(struct ppp_channel *chan, unsigned int cmd,
593 unsigned long arg)
594 {
595 struct sock *sk = (struct sock *) chan->private;
596 struct pppox_sock *po = pppox_sk(sk);
597 struct pptp_opt *opt = &po->proto.pptp;
598 void __user *argp = (void __user *)arg;
599 int __user *p = argp;
600 int err, val;
601
602 err = -EFAULT;
603 switch (cmd) {
604 case PPPIOCGFLAGS:
605 val = opt->ppp_flags;
606 if (put_user(val, p))
607 break;
608 err = 0;
609 break;
610 case PPPIOCSFLAGS:
611 if (get_user(val, p))
612 break;
613 opt->ppp_flags = val & ~SC_RCV_BITS;
614 err = 0;
615 break;
616 default:
617 err = -ENOTTY;
618 }
619
620 return err;
621 }
622
623 static const struct ppp_channel_ops pptp_chan_ops = {
624 .start_xmit = pptp_xmit,
625 .ioctl = pptp_ppp_ioctl,
626 };
627
628 static struct proto pptp_sk_proto __read_mostly = {
629 .name = "PPTP",
630 .owner = THIS_MODULE,
631 .obj_size = sizeof(struct pppox_sock),
632 };
633
634 static const struct proto_ops pptp_ops = {
635 .family = AF_PPPOX,
636 .owner = THIS_MODULE,
637 .release = pptp_release,
638 .bind = pptp_bind,
639 .connect = pptp_connect,
640 .socketpair = sock_no_socketpair,
641 .accept = sock_no_accept,
642 .getname = pptp_getname,
643 .poll = sock_no_poll,
644 .listen = sock_no_listen,
645 .shutdown = sock_no_shutdown,
646 .setsockopt = sock_no_setsockopt,
647 .getsockopt = sock_no_getsockopt,
648 .sendmsg = sock_no_sendmsg,
649 .recvmsg = sock_no_recvmsg,
650 .mmap = sock_no_mmap,
651 .ioctl = pppox_ioctl,
652 };
653
654 static const struct pppox_proto pppox_pptp_proto = {
655 .create = pptp_create,
656 .owner = THIS_MODULE,
657 };
658
659 static const struct gre_protocol gre_pptp_protocol = {
660 .handler = pptp_rcv,
661 };
662
663 static int __init pptp_init_module(void)
664 {
665 int err = 0;
666 pr_info("PPTP driver version " PPTP_DRIVER_VERSION "\n");
667
668 callid_sock = vzalloc((MAX_CALLID + 1) * sizeof(void *));
669 if (!callid_sock) {
670 pr_err("PPTP: cann't allocate memory\n");
671 return -ENOMEM;
672 }
673
674 err = gre_add_protocol(&gre_pptp_protocol, GREPROTO_PPTP);
675 if (err) {
676 pr_err("PPTP: can't add gre protocol\n");
677 goto out_mem_free;
678 }
679
680 err = proto_register(&pptp_sk_proto, 0);
681 if (err) {
682 pr_err("PPTP: can't register sk_proto\n");
683 goto out_gre_del_protocol;
684 }
685
686 err = register_pppox_proto(PX_PROTO_PPTP, &pppox_pptp_proto);
687 if (err) {
688 pr_err("PPTP: can't register pppox_proto\n");
689 goto out_unregister_sk_proto;
690 }
691
692 return 0;
693
694 out_unregister_sk_proto:
695 proto_unregister(&pptp_sk_proto);
696 out_gre_del_protocol:
697 gre_del_protocol(&gre_pptp_protocol, GREPROTO_PPTP);
698 out_mem_free:
699 vfree(callid_sock);
700
701 return err;
702 }
703
704 static void __exit pptp_exit_module(void)
705 {
706 unregister_pppox_proto(PX_PROTO_PPTP);
707 proto_unregister(&pptp_sk_proto);
708 gre_del_protocol(&gre_pptp_protocol, GREPROTO_PPTP);
709 vfree(callid_sock);
710 }
711
712 module_init(pptp_init_module);
713 module_exit(pptp_exit_module);
714
715 MODULE_DESCRIPTION("Point-to-Point Tunneling Protocol");
716 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)");
717 MODULE_LICENSE("GPL");
linux-next