drivers/net/ppp/pptp.c

   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/ppp-ioctl.h>
  27 #include <linux/notifier.h>
  28 #include <linux/file.h>
  29 #include <linux/in.h>
  30 #include <linux/ip.h>
  31 #include <linux/rcupdate.h>
  32 #include <linux/spinlock.h>
  33
  34 #include <net/sock.h>
  35 #include <net/protocol.h>
  36 #include <net/ip.h>
  37 #include <net/icmp.h>
  38 #include <net/route.h>
  39 #include <net/gre.h>
  40
  41 #include <linux/uaccess.h>
  42
  43 #define PPTP_DRIVER_VERSION "0.8.5"
  44
  45 #define MAX_CALLID 65535
  46
  47 static DECLARE_BITMAP(callid_bitmap, MAX_CALLID + 1);
  48 static struct pppox_sock __rcu **callid_sock;
  49
  50 static DEFINE_SPINLOCK(chan_lock);
  51
  52 static struct proto pptp_sk_proto __read_mostly;
  53 static const struct ppp_channel_ops pptp_chan_ops;
  54 static const struct proto_ops pptp_ops;
  55
  56 #define PPP_LCP_ECHOREQ 0x09
  57 #define PPP_LCP_ECHOREP 0x0A
  58 #define SC_RCV_BITS     (SC_RCV_B7_1|SC_RCV_B7_0|SC_RCV_ODDP|SC_RCV_EVNP)
  59
  60 #define MISSING_WINDOW 20
  61 #define WRAPPED(curseq, lastseq)\
  62         ((((curseq) & 0xffffff00) == 0) &&\
  63         (((lastseq) & 0xffffff00) == 0xffffff00))
  64
  65 #define PPTP_GRE_PROTO  0x880B
  66 #define PPTP_GRE_VER    0x1
  67
  68 #define PPTP_GRE_FLAG_C 0x80
  69 #define PPTP_GRE_FLAG_R 0x40
  70 #define PPTP_GRE_FLAG_K 0x20
  71 #define PPTP_GRE_FLAG_S 0x10
  72 #define PPTP_GRE_FLAG_A 0x80
  73
  74 #define PPTP_GRE_IS_C(f) ((f)&PPTP_GRE_FLAG_C)
  75 #define PPTP_GRE_IS_R(f) ((f)&PPTP_GRE_FLAG_R)
  76 #define PPTP_GRE_IS_K(f) ((f)&PPTP_GRE_FLAG_K)
  77 #define PPTP_GRE_IS_S(f) ((f)&PPTP_GRE_FLAG_S)
  78 #define PPTP_GRE_IS_A(f) ((f)&PPTP_GRE_FLAG_A)
  79
  80 #define PPTP_HEADER_OVERHEAD (2+sizeof(struct pptp_gre_header))
  81 struct pptp_gre_header {
  82         u8  flags;
  83         u8  ver;
  84         __be16 protocol;
  85         __be16 payload_len;
  86         __be16 call_id;
  87         __be32 seq;
  88         __be32 ack;
  89 } __packed;
  90
  91 static struct pppox_sock *lookup_chan(u16 call_id, __be32 s_addr)
  92 {
  93         struct pppox_sock *sock;
  94         struct pptp_opt *opt;
  95
  96         rcu_read_lock();
  97         sock = rcu_dereference(callid_sock[call_id]);
  98         if (sock) {
  99                 opt = &sock->proto.pptp;
 100                 if (opt->dst_addr.sin_addr.s_addr != s_addr)
 101                         sock = NULL;
 102                 else
 103                         sock_hold(sk_pppox(sock));
 104         }
 105         rcu_read_unlock();
 106
 107         return sock;
 108 }
 109
 110 static int lookup_chan_dst(u16 call_id, __be32 d_addr)
 111 {
 112         struct pppox_sock *sock;
 113         struct pptp_opt *opt;
 114         int i;
 115
 116         rcu_read_lock();
 117         i = 1;
 118         for_each_set_bit_from(i, callid_bitmap, MAX_CALLID) {
 119                 sock = rcu_dereference(callid_sock[i]);
 120                 if (!sock)
 121                         continue;
 122                 opt = &sock->proto.pptp;
 123                 if (opt->dst_addr.call_id == call_id &&
 124                           opt->dst_addr.sin_addr.s_addr == d_addr)
 125                         break;
 126         }
 127         rcu_read_unlock();
 128
 129         return i < MAX_CALLID;
 130 }
 131
 132 static int add_chan(struct pppox_sock *sock,
 133                     struct pptp_addr *sa)
 134 {
 135         static int call_id;
 136
 137         spin_lock(&chan_lock);
 138         if (!sa->call_id)       {
 139                 call_id = find_next_zero_bit(callid_bitmap, MAX_CALLID, call_id + 1);
 140                 if (call_id == MAX_CALLID) {
 141                         call_id = find_next_zero_bit(callid_bitmap, MAX_CALLID, 1);
 142                         if (call_id == MAX_CALLID)
 143                                 goto out_err;
 144                 }
 145                 sa->call_id = call_id;
 146         } else if (test_bit(sa->call_id, callid_bitmap)) {
 147                 goto out_err;
 148         }
 149
 150         sock->proto.pptp.src_addr = *sa;
 151         set_bit(sa->call_id, callid_bitmap);
 152         rcu_assign_pointer(callid_sock[sa->call_id], sock);
 153         spin_unlock(&chan_lock);
 154
 155         return 0;
 156
 157 out_err:
 158         spin_unlock(&chan_lock);
 159         return -1;
 160 }
 161
 162 static void del_chan(struct pppox_sock *sock)
 163 {
 164         spin_lock(&chan_lock);
 165         clear_bit(sock->proto.pptp.src_addr.call_id, callid_bitmap);
 166         RCU_INIT_POINTER(callid_sock[sock->proto.pptp.src_addr.call_id], NULL);
 167         spin_unlock(&chan_lock);
 168         synchronize_rcu();
 169 }
 170
 171 static int pptp_xmit(struct ppp_channel *chan, struct sk_buff *skb)
 172 {
 173         struct sock *sk = (struct sock *) chan->private;
 174         struct pppox_sock *po = pppox_sk(sk);
 175         struct net *net = sock_net(sk);
 176         struct pptp_opt *opt = &po->proto.pptp;
 177         struct pptp_gre_header *hdr;
 178         unsigned int header_len = sizeof(*hdr);
 179         struct flowi4 fl4;
 180         int islcp;
 181         int len;
 182         unsigned char *data;
 183         __u32 seq_recv;
 184
 185
 186         struct rtable *rt;
 187         struct net_device *tdev;
 188         struct iphdr  *iph;
 189         int    max_headroom;
 190
 191         if (sk_pppox(po)->sk_state & PPPOX_DEAD)
 192                 goto tx_error;
 193
 194         rt = ip_route_output_ports(net, &fl4, NULL,
 195                                    opt->dst_addr.sin_addr.s_addr,
 196                                    opt->src_addr.sin_addr.s_addr,
 197                                    0, 0, IPPROTO_GRE,
 198                                    RT_TOS(0), 0);
 199         if (IS_ERR(rt))
 200                 goto tx_error;
 201
 202         tdev = rt->dst.dev;
 203
 204         max_headroom = LL_RESERVED_SPACE(tdev) + sizeof(*iph) + sizeof(*hdr) + 2;
 205
 206         if (skb_headroom(skb) < max_headroom || skb_cloned(skb) || skb_shared(skb)) {
 207                 struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
 208                 if (!new_skb) {
 209                         ip_rt_put(rt);
 210                         goto tx_error;
 211                 }
 212                 if (skb->sk)
 213                         skb_set_owner_w(new_skb, skb->sk);
 214                 consume_skb(skb);
 215                 skb = new_skb;
 216         }
 217
 218         data = skb->data;
 219         islcp = ((data[0] << 8) + data[1]) == PPP_LCP && 1 <= data[2] && data[2] <= 7;
 220
 221         /* compress protocol field */
 222         if ((opt->ppp_flags & SC_COMP_PROT) && data[0] == 0 && !islcp)
 223                 skb_pull(skb, 1);
 224
 225         /* Put in the address/control bytes if necessary */
 226         if ((opt->ppp_flags & SC_COMP_AC) == 0 || islcp) {
 227                 data = skb_push(skb, 2);
 228                 data[0] = PPP_ALLSTATIONS;
 229                 data[1] = PPP_UI;
 230         }
 231
 232         len = skb->len;
 233
 234         seq_recv = opt->seq_recv;
 235
 236         if (opt->ack_sent == seq_recv)
 237                 header_len -= sizeof(hdr->ack);
 238
 239         /* Push down and install GRE header */
 240         skb_push(skb, header_len);
 241         hdr = (struct pptp_gre_header *)(skb->data);
 242
 243         hdr->flags       = PPTP_GRE_FLAG_K;
 244         hdr->ver         = PPTP_GRE_VER;
 245         hdr->protocol    = htons(PPTP_GRE_PROTO);
 246         hdr->call_id     = htons(opt->dst_addr.call_id);
 247
 248         hdr->flags      |= PPTP_GRE_FLAG_S;
 249         hdr->seq         = htonl(++opt->seq_sent);
 250         if (opt->ack_sent != seq_recv)  {
 251                 /* send ack with this message */
 252                 hdr->ver |= PPTP_GRE_FLAG_A;
 253                 hdr->ack  = htonl(seq_recv);
 254                 opt->ack_sent = seq_recv;
 255         }
 256         hdr->payload_len = htons(len);
 257
 258         /*      Push down and install the IP header. */
 259
 260         skb_reset_transport_header(skb);
 261         skb_push(skb, sizeof(*iph));
 262         skb_reset_network_header(skb);
 263         memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
 264         IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED | IPSKB_REROUTED);
 265
 266         iph =   ip_hdr(skb);
 267         iph->version =  4;
 268         iph->ihl =      sizeof(struct iphdr) >> 2;
 269         if (ip_dont_fragment(sk, &rt->dst))
 270                 iph->frag_off   =       htons(IP_DF);
 271         else
 272                 iph->frag_off   =       0;
 273         iph->protocol = IPPROTO_GRE;
 274         iph->tos      = 0;
 275         iph->daddr    = fl4.daddr;
 276         iph->saddr    = fl4.saddr;
 277         iph->ttl      = ip4_dst_hoplimit(&rt->dst);
 278         iph->tot_len  = htons(skb->len);
 279
 280         skb_dst_drop(skb);
 281         skb_dst_set(skb, &rt->dst);
 282
 283         nf_reset(skb);
 284
 285         skb->ip_summed = CHECKSUM_NONE;
 286         ip_select_ident(net, skb, NULL);
 287         ip_send_check(iph);
 288
 289         ip_local_out(net, skb->sk, skb);
 290         return 1;
 291
 292 tx_error:
 293         kfree_skb(skb);
 294         return 1;
 295 }
 296
 297 static int pptp_rcv_core(struct sock *sk, struct sk_buff *skb)
 298 {
 299         struct pppox_sock *po = pppox_sk(sk);
 300         struct pptp_opt *opt = &po->proto.pptp;
 301         int headersize, payload_len, seq;
 302         __u8 *payload;
 303         struct pptp_gre_header *header;
 304
 305         if (!(sk->sk_state & PPPOX_CONNECTED)) {
 306                 if (sock_queue_rcv_skb(sk, skb))
 307                         goto drop;
 308                 return NET_RX_SUCCESS;
 309         }
 310
 311         header = (struct pptp_gre_header *)(skb->data);
 312         headersize  = sizeof(*header);
 313
 314         /* test if acknowledgement present */
 315         if (PPTP_GRE_IS_A(header->ver)) {
 316                 __u32 ack;
 317
 318                 if (!pskb_may_pull(skb, headersize))
 319                         goto drop;
 320                 header = (struct pptp_gre_header *)(skb->data);
 321
 322                 /* ack in different place if S = 0 */
 323                 ack = PPTP_GRE_IS_S(header->flags) ? header->ack : header->seq;
 324
 325                 ack = ntohl(ack);
 326
 327                 if (ack > opt->ack_recv)
 328                         opt->ack_recv = ack;
 329                 /* also handle sequence number wrap-around  */
 330                 if (WRAPPED(ack, opt->ack_recv))
 331                         opt->ack_recv = ack;
 332         } else {
 333                 headersize -= sizeof(header->ack);
 334         }
 335         /* test if payload present */
 336         if (!PPTP_GRE_IS_S(header->flags))
 337                 goto drop;
 338
 339         payload_len = ntohs(header->payload_len);
 340         seq         = ntohl(header->seq);
 341
 342         /* check for incomplete packet (length smaller than expected) */
 343         if (!pskb_may_pull(skb, headersize + payload_len))
 344                 goto drop;
 345
 346         payload = skb->data + headersize;
 347         /* check for expected sequence number */
 348         if (seq < opt->seq_recv + 1 || WRAPPED(opt->seq_recv, seq)) {
 349                 if ((payload[0] == PPP_ALLSTATIONS) && (payload[1] == PPP_UI) &&
 350                                 (PPP_PROTOCOL(payload) == PPP_LCP) &&
 351                                 ((payload[4] == PPP_LCP_ECHOREQ) || (payload[4] == PPP_LCP_ECHOREP)))
 352                         goto allow_packet;
 353         } else {
 354                 opt->seq_recv = seq;
 355 allow_packet:
 356                 skb_pull(skb, headersize);
 357
 358                 if (payload[0] == PPP_ALLSTATIONS && payload[1] == PPP_UI) {
 359                         /* chop off address/control */
 360                         if (skb->len < 3)
 361                                 goto drop;
 362                         skb_pull(skb, 2);
 363                 }
 364
 365                 if ((*skb->data) & 1) {
 366                         /* protocol is compressed */
 367                         skb_push(skb, 1)[0] = 0;
 368                 }
 369
 370                 skb->ip_summed = CHECKSUM_NONE;
 371                 skb_set_network_header(skb, skb->head-skb->data);
 372                 ppp_input(&po->chan, skb);
 373
 374                 return NET_RX_SUCCESS;
 375         }
 376 drop:
 377         kfree_skb(skb);
 378         return NET_RX_DROP;
 379 }
 380
 381 static int pptp_rcv(struct sk_buff *skb)
 382 {
 383         struct pppox_sock *po;
 384         struct pptp_gre_header *header;
 385         struct iphdr *iph;
 386
 387         if (skb->pkt_type != PACKET_HOST)
 388                 goto drop;
 389
 390         if (!pskb_may_pull(skb, 12))
 391                 goto drop;
 392
 393         iph = ip_hdr(skb);
 394
 395         header = (struct pptp_gre_header *)skb->data;
 396
 397         if (ntohs(header->protocol) != PPTP_GRE_PROTO || /* PPTP-GRE protocol for PPTP */
 398                 PPTP_GRE_IS_C(header->flags) ||                /* flag C should be clear */
 399                 PPTP_GRE_IS_R(header->flags) ||                /* flag R should be clear */
 400                 !PPTP_GRE_IS_K(header->flags) ||               /* flag K should be set */
 401                 (header->flags&0xF) != 0)                      /* routing and recursion ctrl = 0 */
 402                 /* if invalid, discard this packet */
 403                 goto drop;
 404
 405         po = lookup_chan(htons(header->call_id), iph->saddr);
 406         if (po) {
 407                 skb_dst_drop(skb);
 408                 nf_reset(skb);
 409                 return sk_receive_skb(sk_pppox(po), skb, 0);
 410         }
 411 drop:
 412         kfree_skb(skb);
 413         return NET_RX_DROP;
 414 }
 415
 416 static int pptp_bind(struct socket *sock, struct sockaddr *uservaddr,
 417         int sockaddr_len)
 418 {
 419         struct sock *sk = sock->sk;
 420         struct sockaddr_pppox *sp = (struct sockaddr_pppox *) uservaddr;
 421         struct pppox_sock *po = pppox_sk(sk);
 422         int error = 0;
 423
 424         if (sockaddr_len < sizeof(struct sockaddr_pppox))
 425                 return -EINVAL;
 426
 427         lock_sock(sk);
 428
 429         if (sk->sk_state & PPPOX_DEAD) {
 430                 error = -EALREADY;
 431                 goto out;
 432         }
 433
 434         if (sk->sk_state & PPPOX_BOUND) {
 435                 error = -EBUSY;
 436                 goto out;
 437         }
 438
 439         if (add_chan(po, &sp->sa_addr.pptp))
 440                 error = -EBUSY;
 441         else
 442                 sk->sk_state |= PPPOX_BOUND;
 443
 444 out:
 445         release_sock(sk);
 446         return error;
 447 }
 448
 449 static int pptp_connect(struct socket *sock, struct sockaddr *uservaddr,
 450         int sockaddr_len, int flags)
 451 {
 452         struct sock *sk = sock->sk;
 453         struct sockaddr_pppox *sp = (struct sockaddr_pppox *) uservaddr;
 454         struct pppox_sock *po = pppox_sk(sk);
 455         struct pptp_opt *opt = &po->proto.pptp;
 456         struct rtable *rt;
 457         struct flowi4 fl4;
 458         int error = 0;
 459
 460         if (sockaddr_len < sizeof(struct sockaddr_pppox))
 461                 return -EINVAL;
 462
 463         if (sp->sa_protocol != PX_PROTO_PPTP)
 464                 return -EINVAL;
 465
 466         if (lookup_chan_dst(sp->sa_addr.pptp.call_id, sp->sa_addr.pptp.sin_addr.s_addr))
 467                 return -EALREADY;
 468
 469         lock_sock(sk);
 470         /* Check for already bound sockets */
 471         if (sk->sk_state & PPPOX_CONNECTED) {
 472                 error = -EBUSY;
 473                 goto end;
 474         }
 475
 476         /* Check for already disconnected sockets, on attempts to disconnect */
 477         if (sk->sk_state & PPPOX_DEAD) {
 478                 error = -EALREADY;
 479                 goto end;
 480         }
 481
 482         if (!opt->src_addr.sin_addr.s_addr || !sp->sa_addr.pptp.sin_addr.s_addr) {
 483                 error = -EINVAL;
 484                 goto end;
 485         }
 486
 487         po->chan.private = sk;
 488         po->chan.ops = &pptp_chan_ops;
 489
 490         rt = ip_route_output_ports(sock_net(sk), &fl4, sk,
 491                                    opt->dst_addr.sin_addr.s_addr,
 492                                    opt->src_addr.sin_addr.s_addr,
 493                                    0, 0,
 494                                    IPPROTO_GRE, RT_CONN_FLAGS(sk), 0);
 495         if (IS_ERR(rt)) {
 496                 error = -EHOSTUNREACH;
 497                 goto end;
 498         }
 499         sk_setup_caps(sk, &rt->dst);
 500
 501         po->chan.mtu = dst_mtu(&rt->dst);
 502         if (!po->chan.mtu)
 503                 po->chan.mtu = PPP_MRU;
 504         ip_rt_put(rt);
 505         po->chan.mtu -= PPTP_HEADER_OVERHEAD;
 506
 507         po->chan.hdrlen = 2 + sizeof(struct pptp_gre_header);
 508         error = ppp_register_channel(&po->chan);
 509         if (error) {
 510                 pr_err("PPTP: failed to register PPP channel (%d)\n", error);
 511                 goto end;
 512         }
 513
 514         opt->dst_addr = sp->sa_addr.pptp;
 515         sk->sk_state |= PPPOX_CONNECTED;
 516
 517  end:
 518         release_sock(sk);
 519         return error;
 520 }
 521
 522 static int pptp_getname(struct socket *sock, struct sockaddr *uaddr,
 523         int *usockaddr_len, int peer)
 524 {
 525         int len = sizeof(struct sockaddr_pppox);
 526         struct sockaddr_pppox sp;
 527
 528         memset(&sp.sa_addr, 0, sizeof(sp.sa_addr));
 529
 530         sp.sa_family    = AF_PPPOX;
 531         sp.sa_protocol  = PX_PROTO_PPTP;
 532         sp.sa_addr.pptp = pppox_sk(sock->sk)->proto.pptp.src_addr;
 533
 534         memcpy(uaddr, &sp, len);
 535
 536         *usockaddr_len = len;
 537
 538         return 0;
 539 }
 540
 541 static int pptp_release(struct socket *sock)
 542 {
 543         struct sock *sk = sock->sk;
 544         struct pppox_sock *po;
 545         struct pptp_opt *opt;
 546         int error = 0;
 547
 548         if (!sk)
 549                 return 0;
 550
 551         lock_sock(sk);
 552
 553         if (sock_flag(sk, SOCK_DEAD)) {
 554                 release_sock(sk);
 555                 return -EBADF;
 556         }
 557
 558         po = pppox_sk(sk);
 559         opt = &po->proto.pptp;
 560         del_chan(po);
 561
 562         pppox_unbind_sock(sk);
 563         sk->sk_state = PPPOX_DEAD;
 564
 565         sock_orphan(sk);
 566         sock->sk = NULL;
 567
 568         release_sock(sk);
 569         sock_put(sk);
 570
 571         return error;
 572 }
 573
 574 static void pptp_sock_destruct(struct sock *sk)
 575 {
 576         if (!(sk->sk_state & PPPOX_DEAD)) {
 577                 del_chan(pppox_sk(sk));
 578                 pppox_unbind_sock(sk);
 579         }
 580         skb_queue_purge(&sk->sk_receive_queue);
 581 }
 582
 583 static int pptp_create(struct net *net, struct socket *sock, int kern)
 584 {
 585         int error = -ENOMEM;
 586         struct sock *sk;
 587         struct pppox_sock *po;
 588         struct pptp_opt *opt;
 589
 590         sk = sk_alloc(net, PF_PPPOX, GFP_KERNEL, &pptp_sk_proto, kern);
 591         if (!sk)
 592                 goto out;
 593
 594         sock_init_data(sock, sk);
 595
 596         sock->state = SS_UNCONNECTED;
 597         sock->ops   = &pptp_ops;
 598
 599         sk->sk_backlog_rcv = pptp_rcv_core;
 600         sk->sk_state       = PPPOX_NONE;
 601         sk->sk_type        = SOCK_STREAM;
 602         sk->sk_family      = PF_PPPOX;
 603         sk->sk_protocol    = PX_PROTO_PPTP;
 604         sk->sk_destruct    = pptp_sock_destruct;
 605
 606         po = pppox_sk(sk);
 607         opt = &po->proto.pptp;
 608
 609         opt->seq_sent = 0; opt->seq_recv = 0xffffffff;
 610         opt->ack_recv = 0; opt->ack_sent = 0xffffffff;
 611
 612         error = 0;
 613 out:
 614         return error;
 615 }
 616
 617 static int pptp_ppp_ioctl(struct ppp_channel *chan, unsigned int cmd,
 618         unsigned long arg)
 619 {
 620         struct sock *sk = (struct sock *) chan->private;
 621         struct pppox_sock *po = pppox_sk(sk);
 622         struct pptp_opt *opt = &po->proto.pptp;
 623         void __user *argp = (void __user *)arg;
 624         int __user *p = argp;
 625         int err, val;
 626
 627         err = -EFAULT;
 628         switch (cmd) {
 629         case PPPIOCGFLAGS:
 630                 val = opt->ppp_flags;
 631                 if (put_user(val, p))
 632                         break;
 633                 err = 0;
 634                 break;
 635         case PPPIOCSFLAGS:
 636                 if (get_user(val, p))
 637                         break;
 638                 opt->ppp_flags = val & ~SC_RCV_BITS;
 639                 err = 0;
 640                 break;
 641         default:
 642                 err = -ENOTTY;
 643         }
 644
 645         return err;
 646 }
 647
 648 static const struct ppp_channel_ops pptp_chan_ops = {
 649         .start_xmit = pptp_xmit,
 650         .ioctl      = pptp_ppp_ioctl,
 651 };
 652
 653 static struct proto pptp_sk_proto __read_mostly = {
 654         .name     = "PPTP",
 655         .owner    = THIS_MODULE,
 656         .obj_size = sizeof(struct pppox_sock),
 657 };
 658
 659 static const struct proto_ops pptp_ops = {
 660         .family     = AF_PPPOX,
 661         .owner      = THIS_MODULE,
 662         .release    = pptp_release,
 663         .bind       = pptp_bind,
 664         .connect    = pptp_connect,
 665         .socketpair = sock_no_socketpair,
 666         .accept     = sock_no_accept,
 667         .getname    = pptp_getname,
 668         .poll       = sock_no_poll,
 669         .listen     = sock_no_listen,
 670         .shutdown   = sock_no_shutdown,
 671         .setsockopt = sock_no_setsockopt,
 672         .getsockopt = sock_no_getsockopt,
 673         .sendmsg    = sock_no_sendmsg,
 674         .recvmsg    = sock_no_recvmsg,
 675         .mmap       = sock_no_mmap,
 676         .ioctl      = pppox_ioctl,
 677 };
 678
 679 static const struct pppox_proto pppox_pptp_proto = {
 680         .create = pptp_create,
 681         .owner  = THIS_MODULE,
 682 };
 683
 684 static const struct gre_protocol gre_pptp_protocol = {
 685         .handler = pptp_rcv,
 686 };
 687
 688 static int __init pptp_init_module(void)
 689 {
 690         int err = 0;
 691         pr_info("PPTP driver version " PPTP_DRIVER_VERSION "\n");
 692
 693         callid_sock = vzalloc((MAX_CALLID + 1) * sizeof(void *));
 694         if (!callid_sock)
 695                 return -ENOMEM;
 696
 697         err = gre_add_protocol(&gre_pptp_protocol, GREPROTO_PPTP);
 698         if (err) {
 699                 pr_err("PPTP: can't add gre protocol\n");
 700                 goto out_mem_free;
 701         }
 702
 703         err = proto_register(&pptp_sk_proto, 0);
 704         if (err) {
 705                 pr_err("PPTP: can't register sk_proto\n");
 706                 goto out_gre_del_protocol;
 707         }
 708
 709         err = register_pppox_proto(PX_PROTO_PPTP, &pppox_pptp_proto);
 710         if (err) {
 711                 pr_err("PPTP: can't register pppox_proto\n");
 712                 goto out_unregister_sk_proto;
 713         }
 714
 715         return 0;
 716
 717 out_unregister_sk_proto:
 718         proto_unregister(&pptp_sk_proto);
 719 out_gre_del_protocol:
 720         gre_del_protocol(&gre_pptp_protocol, GREPROTO_PPTP);
 721 out_mem_free:
 722         vfree(callid_sock);
 723
 724         return err;
 725 }
 726
 727 static void __exit pptp_exit_module(void)
 728 {
 729         unregister_pppox_proto(PX_PROTO_PPTP);
 730         proto_unregister(&pptp_sk_proto);
 731         gre_del_protocol(&gre_pptp_protocol, GREPROTO_PPTP);
 732         vfree(callid_sock);
 733 }
 734
 735 module_init(pptp_init_module);
 736 module_exit(pptp_exit_module);
 737
 738 MODULE_DESCRIPTION("Point-to-Point Tunneling Protocol");
 739 MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)");
 740 MODULE_LICENSE("GPL");
 741 MODULE_ALIAS_NET_PF_PROTO(PF_PPPOX, PX_PROTO_PPTP);