drivers/net/pppoe.c

   1 /** -*- linux-c -*- ***********************************************************
   2  * Linux PPP over Ethernet (PPPoX/PPPoE) Sockets
   3  *
   4  * PPPoX --- Generic PPP encapsulation socket family
   5  * PPPoE --- PPP over Ethernet (RFC 2516)
   6  *
   7  *
   8  * Version:    0.6.11
   9  *
  10  * 030700 :     Fixed connect logic to allow for disconnect.
  11  * 270700 :     Fixed potential SMP problems; we must protect against
  12  *              simultaneous invocation of ppp_input
  13  *              and ppp_unregister_channel.
  14  * 040800 :     Respect reference count mechanisms on net-devices.
  15  * 200800 :     fix kfree(skb) in pppoe_rcv (acme)
  16  *              Module reference count is decremented in the right spot now,
  17  *              guards against sock_put not actually freeing the sk
  18  *              in pppoe_release.
  19  * 051000 :     Initialization cleanup.
  20  * 111100 :     Fix recvmsg.
  21  * 050101 :     Fix PADT procesing.
  22  * 140501 :     Use pppoe_rcv_core to handle all backlog. (Alexey)
  23  * 170701 :     Do not lock_sock with rwlock held. (DaveM)
  24  *              Ignore discovery frames if user has socket
  25  *              locked. (DaveM)
  26  *              Ignore return value of dev_queue_xmit in __pppoe_xmit
  27  *              or else we may kfree an SKB twice. (DaveM)
  28  * 190701 :     When doing copies of skb's in __pppoe_xmit, always delete
  29  *              the original skb that was passed in on success, never on
  30  *              failure.  Delete the copy of the skb on failure to avoid
  31  *              a memory leak.
  32  * 081001 :     Misc. cleanup (licence string, non-blocking, prevent
  33  *              reference of device on close).
  34  * 121301 :     New ppp channels interface; cannot unregister a channel
  35  *              from interrupts.  Thus, we mark the socket as a ZOMBIE
  36  *              and do the unregistration later.
  37  * 071502 :     When a connection is being torn down, we must remember that
  38  *              ZOMBIE state connections are still connected and thus
  39  *              pppox_unbind_sock must unbind them (in pppoe_release).
  40  *
  41  * Author:      Michal Ostrowski <mostrows@speakeasy.net>
  42  * Contributors:
  43  *              Arnaldo Carvalho de Melo <acme@xconectiva.com.br>
  44  *              David S. Miller (davem@redhat.com)
  45  *
  46  * License:
  47  *              This program is free software; you can redistribute it and/or
  48  *              modify it under the terms of the GNU General Public License
  49  *              as published by the Free Software Foundation; either version
  50  *              2 of the License, or (at your option) any later version.
  51  *
  52  */
  53
  54 #include <linux/string.h>
  55 #include <linux/module.h>
  56
  57 #include <asm/uaccess.h>
  58
  59 #include <linux/kernel.h>
  60 #include <linux/sched.h>
  61 #include <linux/slab.h>
  62 #include <linux/errno.h>
  63
  64 #include <linux/netdevice.h>
  65 #include <linux/net.h>
  66 #include <linux/inetdevice.h>
  67 #include <linux/etherdevice.h>
  68 #include <linux/skbuff.h>
  69 #include <linux/init.h>
  70 #include <linux/if_ether.h>
  71 #include <linux/if_pppox.h>
  72 #include <net/sock.h>
  73 #include <linux/ppp_channel.h>
  74 #include <linux/ppp_defs.h>
  75 #include <linux/if_ppp.h>
  76 #include <linux/if_pppvar.h>
  77 #include <linux/notifier.h>
  78 #include <linux/file.h>
  79 #include <linux/proc_fs.h>
  80
  81
  82
  83 static int __attribute__((unused)) pppoe_debug = 7;
  84 #define PPPOE_HASH_BITS 4
  85 #define PPPOE_HASH_SIZE (1<<PPPOE_HASH_BITS)
  86
  87 int pppoe_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg);
  88 int pppoe_xmit(struct ppp_channel *chan, struct sk_buff *skb);
  89 int __pppoe_xmit(struct sock *sk, struct sk_buff *skb);
  90
  91 struct proto_ops pppoe_ops;
  92
  93
  94 #if 0
  95 #define CHECKPTR(x,y) do { if (!(x) && pppoe_debug &7 ){ printk(KERN_CRIT "PPPoE Invalid pointer : %s , %p\n",#x,(x)); error=-EINVAL; goto y; }} while (0)
  96 #define DEBUG(s,args...) do { if( pppoe_debug & (s) ) printk(KERN_CRIT args ); } while (0)
  97 #else
  98 #define CHECKPTR(x,y) do { } while (0)
  99 #define DEBUG(s,args...) do { } while (0)
 100 #endif
 101
 102
 103
 104 static rwlock_t pppoe_hash_lock = RW_LOCK_UNLOCKED;
 105
 106
 107 static inline int cmp_2_addr(struct pppoe_addr *a, struct pppoe_addr *b)
 108 {
 109         return (a->sid == b->sid &&
 110                 (memcmp(a->remote, b->remote, ETH_ALEN) == 0));
 111 }
 112
 113 static inline int cmp_addr(struct pppoe_addr *a, unsigned long sid, char *addr)
 114 {
 115         return (a->sid == sid &&
 116                 (memcmp(a->remote,addr,ETH_ALEN) == 0));
 117 }
 118
 119 static int hash_item(unsigned long sid, unsigned char *addr)
 120 {
 121         char hash = 0;
 122         int i, j;
 123
 124         for (i = 0; i < ETH_ALEN ; ++i) {
 125                 for (j = 0; j < 8/PPPOE_HASH_BITS ; ++j) {
 126                         hash ^= addr[i] >> ( j * PPPOE_HASH_BITS );
 127                 }
 128         }
 129
 130         for (i = 0; i < (sizeof(unsigned long)*8) / PPPOE_HASH_BITS ; ++i)
 131                 hash ^= sid >> (i*PPPOE_HASH_BITS);
 132
 133         return hash & ( PPPOE_HASH_SIZE - 1 );
 134 }
 135
 136 static struct pppox_opt *item_hash_table[PPPOE_HASH_SIZE] = { 0, };
 137
 138 /**********************************************************************
 139  *
 140  *  Set/get/delete/rehash items  (internal versions)
 141  *
 142  **********************************************************************/
 143 static struct pppox_opt *__get_item(unsigned long sid, unsigned char *addr)
 144 {
 145         int hash = hash_item(sid, addr);
 146         struct pppox_opt *ret;
 147
 148         ret = item_hash_table[hash];
 149
 150         while (ret && !cmp_addr(&ret->pppoe_pa, sid, addr))
 151                 ret = ret->next;
 152
 153         return ret;
 154 }
 155
 156 static int __set_item(struct pppox_opt *po)
 157 {
 158         int hash = hash_item(po->pppoe_pa.sid, po->pppoe_pa.remote);
 159         struct pppox_opt *ret;
 160
 161         ret = item_hash_table[hash];
 162         while (ret) {
 163                 if (cmp_2_addr(&ret->pppoe_pa, &po->pppoe_pa))
 164                         return -EALREADY;
 165
 166                 ret = ret->next;
 167         }
 168
 169         if (!ret) {
 170                 po->next = item_hash_table[hash];
 171                 item_hash_table[hash] = po;
 172         }
 173
 174         return 0;
 175 }
 176
 177 static struct pppox_opt *__delete_item(unsigned long sid, char *addr)
 178 {
 179         int hash = hash_item(sid, addr);
 180         struct pppox_opt *ret, **src;
 181
 182         ret = item_hash_table[hash];
 183         src = &item_hash_table[hash];
 184
 185         while (ret) {
 186                 if (cmp_addr(&ret->pppoe_pa, sid, addr)) {
 187                         *src = ret->next;
 188                         break;
 189                 }
 190
 191                 src = &ret->next;
 192                 ret = ret->next;
 193         }
 194
 195         return ret;
 196 }
 197
 198 /**********************************************************************
 199  *
 200  *  Set/get/delete/rehash items
 201  *
 202  **********************************************************************/
 203 static inline struct pppox_opt *get_item(unsigned long sid,
 204                                          unsigned char *addr)
 205 {
 206         struct pppox_opt *po;
 207
 208         read_lock_bh(&pppoe_hash_lock);
 209         po = __get_item(sid, addr);
 210         if (po)
 211                 sock_hold(po->sk);
 212         read_unlock_bh(&pppoe_hash_lock);
 213
 214         return po;
 215 }
 216
 217 static inline struct pppox_opt *get_item_by_addr(struct sockaddr_pppox *sp)
 218 {
 219         return get_item(sp->sa_addr.pppoe.sid, sp->sa_addr.pppoe.remote);
 220 }
 221
 222 static inline int set_item(struct pppox_opt *po)
 223 {
 224         int i;
 225
 226         if (!po)
 227                 return -EINVAL;
 228
 229         write_lock_bh(&pppoe_hash_lock);
 230         i = __set_item(po);
 231         write_unlock_bh(&pppoe_hash_lock);
 232
 233         return i;
 234 }
 235
 236 static inline struct pppox_opt *delete_item(unsigned long sid, char *addr)
 237 {
 238         struct pppox_opt *ret;
 239
 240         write_lock_bh(&pppoe_hash_lock);
 241         ret = __delete_item(sid, addr);
 242         write_unlock_bh(&pppoe_hash_lock);
 243
 244         return ret;
 245 }
 246
 247
 248
 249 /***************************************************************************
 250  *
 251  *  Handler for device events.
 252  *  Certain device events require that sockets be unconnected.
 253  *
 254  **************************************************************************/
 255
 256 static void pppoe_flush_dev(struct net_device *dev)
 257 {
 258         int hash;
 259
 260         if (dev == NULL)
 261                 BUG();
 262
 263         read_lock_bh(&pppoe_hash_lock);
 264         for (hash = 0; hash < PPPOE_HASH_SIZE; hash++) {
 265                 struct pppox_opt *po = item_hash_table[hash];
 266
 267                 while (po != NULL) {
 268                         if (po->pppoe_dev == dev) {
 269                                 struct sock *sk = po->sk;
 270
 271                                 sock_hold(sk);
 272                                 po->pppoe_dev = NULL;
 273
 274                                 /* We hold a reference to SK, now drop the
 275                                  * hash table lock so that we may attempt
 276                                  * to lock the socket (which can sleep).
 277                                  */
 278                                 read_unlock_bh(&pppoe_hash_lock);
 279
 280                                 lock_sock(sk);
 281
 282                                 if (sk->state & (PPPOX_CONNECTED|PPPOX_BOUND)){
 283                                         pppox_unbind_sock(sk);
 284                                         dev_put(dev);
 285                                         sk->state = PPPOX_ZOMBIE;
 286                                         sk->state_change(sk);
 287                                 }
 288
 289                                 release_sock(sk);
 290
 291                                 sock_put(sk);
 292
 293                                 read_lock_bh(&pppoe_hash_lock);
 294
 295                                 /* Now restart from the beginning of this
 296                                  * hash chain.  We always NULL out pppoe_dev
 297                                  * so we are guarenteed to make forward
 298                                  * progress.
 299                                  */
 300                                 po = item_hash_table[hash];
 301                                 continue;
 302                         }
 303                         po = po->next;
 304                 }
 305         }
 306         read_unlock_bh(&pppoe_hash_lock);
 307 }
 308
 309 static int pppoe_device_event(struct notifier_block *this,
 310                               unsigned long event, void *ptr)
 311 {
 312         struct net_device *dev = (struct net_device *) ptr;
 313
 314         /* Only look at sockets that are using this specific device. */
 315         switch (event) {
 316         case NETDEV_CHANGEMTU:
 317                 /* A change in mtu is a bad thing, requiring
 318                  * LCP re-negotiation.
 319                  */
 320
 321         case NETDEV_GOING_DOWN:
 322         case NETDEV_DOWN:
 323                 /* Find every socket on this device and kill it. */
 324                 pppoe_flush_dev(dev);
 325                 break;
 326
 327         default:
 328                 break;
 329         };
 330
 331         return NOTIFY_DONE;
 332 }
 333
 334
 335 static struct notifier_block pppoe_notifier = {
 336         notifier_call: pppoe_device_event,
 337 };
 338
 339
 340
 341
 342 /************************************************************************
 343  *
 344  * Do the real work of receiving a PPPoE Session frame.
 345  *
 346  ***********************************************************************/
 347 int pppoe_rcv_core(struct sock *sk, struct sk_buff *skb)
 348 {
 349         struct pppox_opt *po = sk->protinfo.pppox;
 350         struct pppox_opt *relay_po = NULL;
 351
 352         if (sk->state & PPPOX_BOUND) {
 353                 ppp_input(&po->chan, skb);
 354         } else if (sk->state & PPPOX_RELAY) {
 355                 relay_po = get_item_by_addr(&po->pppoe_relay);
 356
 357                 if (relay_po == NULL)
 358                         goto abort_kfree;
 359
 360                 if ((relay_po->sk->state & PPPOX_CONNECTED) == 0)
 361                         goto abort_put;
 362
 363                 if (!__pppoe_xmit( relay_po->sk , skb))
 364                         goto abort_put;
 365         } else {
 366                 if (sock_queue_rcv_skb(sk, skb))
 367                         goto abort_kfree;
 368         }
 369
 370         return NET_RX_SUCCESS;
 371
 372 abort_put:
 373         sock_put(relay_po->sk);
 374
 375 abort_kfree:
 376         kfree_skb(skb);
 377         return NET_RX_DROP;
 378 }
 379
 380 /************************************************************************
 381  *
 382  * Receive wrapper called in BH context.
 383  *
 384  ***********************************************************************/
 385 static int pppoe_rcv(struct sk_buff *skb,
 386                       struct net_device *dev,
 387                       struct packet_type *pt)
 388
 389 {
 390         struct pppoe_hdr *ph = (struct pppoe_hdr *) skb->nh.raw;
 391         int len = ntohs(ph->length);
 392         struct pppox_opt *po;
 393         struct sock *sk ;
 394         int ret;
 395
 396         skb_pull(skb, sizeof(*ph));
 397         if (skb->len < len)
 398                 goto drop;
 399
 400         po = get_item((unsigned long) ph->sid, skb->mac.ethernet->h_source);
 401         if (!po)
 402                 goto drop;
 403
 404         if (pskb_trim(skb, len))
 405                 goto drop;
 406
 407         sk = po->sk;
 408         bh_lock_sock(sk);
 409
 410         /* Socket state is unknown, must put skb into backlog. */
 411         if (sk->lock.users != 0) {
 412                 sk_add_backlog(sk, skb);
 413                 ret = NET_RX_SUCCESS;
 414         } else {
 415                 ret = pppoe_rcv_core(sk, skb);
 416         }
 417
 418         bh_unlock_sock(sk);
 419         sock_put(sk);
 420
 421         return ret;
 422  drop:
 423         kfree_skb(skb);
 424         return NET_RX_DROP;
 425 }
 426
 427 /************************************************************************
 428  *
 429  * Receive a PPPoE Discovery frame.
 430  * This is solely for detection of PADT frames
 431  *
 432  ***********************************************************************/
 433 static int pppoe_disc_rcv(struct sk_buff *skb,
 434                           struct net_device *dev,
 435                           struct packet_type *pt)
 436
 437 {
 438         struct pppoe_hdr *ph = (struct pppoe_hdr *) skb->nh.raw;
 439         struct pppox_opt *po;
 440
 441         if (ph->code != PADT_CODE)
 442                 goto abort;
 443
 444         po = get_item((unsigned long) ph->sid, skb->mac.ethernet->h_source);
 445         if (po) {
 446                 struct sock *sk = po->sk;
 447
 448                 bh_lock_sock(sk);
 449
 450                 /* If the user has locked the socket, just ignore
 451                  * the packet.  With the way two rcv protocols hook into
 452                  * one socket family type, we cannot (easily) distinguish
 453                  * what kind of SKB it is during backlog rcv.
 454                  */
 455                 if (sk->lock.users == 0) {
 456                         /* We're no longer connect at the PPPOE layer,
 457                          * and must wait for ppp channel to disconnect us.
 458                          */
 459                         sk->state = PPPOX_ZOMBIE;
 460                 }
 461
 462                 bh_unlock_sock(sk);
 463                 sock_put(sk);
 464         }
 465
 466 abort:
 467         kfree_skb(skb);
 468         return NET_RX_SUCCESS; /* Lies... :-) */
 469 }
 470
 471 struct packet_type pppoes_ptype = {
 472         type:   __constant_htons(ETH_P_PPP_SES),
 473         func:   pppoe_rcv,
 474 };
 475
 476 struct packet_type pppoed_ptype = {
 477         type:   __constant_htons(ETH_P_PPP_DISC),
 478         func:   pppoe_disc_rcv,
 479 };
 480
 481 /***********************************************************************
 482  *
 483  * Really kill the socket. (Called from sock_put if refcnt == 0.)
 484  *
 485  **********************************************************************/
 486 void pppoe_sock_destruct(struct sock *sk)
 487 {
 488         if (sk->protinfo.destruct_hook)
 489                 kfree(sk->protinfo.destruct_hook);
 490         MOD_DEC_USE_COUNT;
 491 }
 492
 493
 494 /***********************************************************************
 495  *
 496  * Initialize a new struct sock.
 497  *
 498  **********************************************************************/
 499 static int pppoe_create(struct socket *sock)
 500 {
 501         int error = 0;
 502         struct sock *sk;
 503
 504         MOD_INC_USE_COUNT;
 505
 506         sk = sk_alloc(PF_PPPOX, GFP_KERNEL, 1);
 507         if (!sk)
 508                 return -ENOMEM;
 509
 510         sock_init_data(sock, sk);
 511
 512         sock->state = SS_UNCONNECTED;
 513         sock->ops   = &pppoe_ops;
 514
 515         sk->protocol = PX_PROTO_OE;
 516         sk->family = PF_PPPOX;
 517
 518         sk->backlog_rcv = pppoe_rcv_core;
 519         sk->next = NULL;
 520         sk->pprev = NULL;
 521         sk->state = PPPOX_NONE;
 522         sk->type = SOCK_STREAM;
 523         sk->destruct = pppoe_sock_destruct;
 524
 525         sk->protinfo.pppox = kmalloc(sizeof(struct pppox_opt), GFP_KERNEL);
 526         if (!sk->protinfo.pppox) {
 527                 error = -ENOMEM;
 528                 goto free_sk;
 529         }
 530
 531         memset((void *) sk->protinfo.pppox, 0, sizeof(struct pppox_opt));
 532         sk->protinfo.pppox->sk = sk;
 533
 534         /* Delete the protinfo when it is time to do so. */
 535         sk->protinfo.destruct_hook = sk->protinfo.pppox;
 536         sock->sk = sk;
 537
 538         return 0;
 539
 540 free_sk:
 541         sk_free(sk);
 542         return error;
 543 }
 544
 545 int pppoe_release(struct socket *sock)
 546 {
 547         struct sock *sk = sock->sk;
 548         struct pppox_opt *po;
 549         int error = 0;
 550
 551         if (!sk)
 552                 return 0;
 553
 554         if (sk->dead != 0)
 555                 return -EBADF;
 556
 557         pppox_unbind_sock(sk);
 558
 559         /* Signal the death of the socket. */
 560         sk->state = PPPOX_DEAD;
 561
 562         po = sk->protinfo.pppox;
 563         if (po->pppoe_pa.sid) {
 564                 delete_item(po->pppoe_pa.sid, po->pppoe_pa.remote);
 565         }
 566
 567         if (po->pppoe_dev)
 568                 dev_put(po->pppoe_dev);
 569
 570         po->pppoe_dev = NULL;
 571
 572         sock_orphan(sk);
 573         sock->sk = NULL;
 574
 575         skb_queue_purge(&sk->receive_queue);
 576         sock_put(sk);
 577
 578         return error;
 579 }
 580
 581
 582 int pppoe_connect(struct socket *sock, struct sockaddr *uservaddr,
 583                   int sockaddr_len, int flags)
 584 {
 585         struct sock *sk = sock->sk;
 586         struct net_device *dev = NULL;
 587         struct sockaddr_pppox *sp = (struct sockaddr_pppox *) uservaddr;
 588         struct pppox_opt *po = sk->protinfo.pppox;
 589         int error;
 590
 591         lock_sock(sk);
 592
 593         error = -EINVAL;
 594         if (sp->sa_protocol != PX_PROTO_OE)
 595                 goto end;
 596
 597         /* Check for already bound sockets */
 598         error = -EBUSY;
 599         if ((sk->state & PPPOX_CONNECTED) && sp->sa_addr.pppoe.sid)
 600                 goto end;
 601
 602         /* Check for already disconnected sockets,
 603            on attempts to disconnect */
 604         error = -EALREADY;
 605         if((sk->state & PPPOX_DEAD) && !sp->sa_addr.pppoe.sid )
 606                 goto end;
 607
 608         error = 0;
 609         if (po->pppoe_pa.sid) {
 610                 pppox_unbind_sock(sk);
 611
 612                 /* Delete the old binding */
 613                 delete_item(po->pppoe_pa.sid,po->pppoe_pa.remote);
 614
 615                 if(po->pppoe_dev)
 616                         dev_put(po->pppoe_dev);
 617
 618                 memset(po, 0, sizeof(struct pppox_opt));
 619                 po->sk = sk;
 620
 621                 sk->state = PPPOX_NONE;
 622         }
 623
 624         /* Don't re-bind if sid==0 */
 625         if (sp->sa_addr.pppoe.sid != 0) {
 626                 dev = dev_get_by_name(sp->sa_addr.pppoe.dev);
 627
 628                 error = -ENODEV;
 629                 if (!dev)
 630                         goto end;
 631
 632                 po->pppoe_dev = dev;
 633
 634                 if (!(dev->flags & IFF_UP))
 635                         goto err_put;
 636
 637                 memcpy(&po->pppoe_pa,
 638                        &sp->sa_addr.pppoe,
 639                        sizeof(struct pppoe_addr));
 640
 641                 error = set_item(po);
 642                 if (error < 0)
 643                         goto err_put;
 644
 645                 po->chan.hdrlen = (sizeof(struct pppoe_hdr) +
 646                                    dev->hard_header_len);
 647
 648                 po->chan.mtu = dev->mtu - sizeof(struct pppoe_hdr);
 649                 po->chan.private = sk;
 650                 po->chan.ops = &pppoe_chan_ops;
 651
 652                 error = ppp_register_channel(&po->chan);
 653                 if (error)
 654                         goto err_put;
 655
 656                 sk->state = PPPOX_CONNECTED;
 657         }
 658
 659         sk->num = sp->sa_addr.pppoe.sid;
 660
 661  end:
 662         release_sock(sk);
 663         return error;
 664 err_put:
 665         if (po->pppoe_dev) {
 666                 dev_put(po->pppoe_dev);
 667                 po->pppoe_dev = NULL;
 668         }
 669         goto end;
 670 }
 671
 672
 673 int pppoe_getname(struct socket *sock, struct sockaddr *uaddr,
 674                   int *usockaddr_len, int peer)
 675 {
 676         int len = sizeof(struct sockaddr_pppox);
 677         struct sockaddr_pppox sp;
 678
 679         sp.sa_family    = AF_PPPOX;
 680         sp.sa_protocol  = PX_PROTO_OE;
 681         memcpy(&sp.sa_addr.pppoe, &sock->sk->protinfo.pppox->pppoe_pa,
 682                sizeof(struct pppoe_addr));
 683
 684         memcpy(uaddr, &sp, len);
 685
 686         *usockaddr_len = len;
 687
 688         return 0;
 689 }
 690
 691
 692 int pppoe_ioctl(struct socket *sock, unsigned int cmd,
 693                 unsigned long arg)
 694 {
 695         struct sock *sk = sock->sk;
 696         struct pppox_opt *po;
 697         int val = 0;
 698         int err = 0;
 699
 700         po = sk->protinfo.pppox;
 701         switch (cmd) {
 702         case PPPIOCGMRU:
 703                 err = -ENXIO;
 704
 705                 if (!(sk->state & PPPOX_CONNECTED))
 706                         break;
 707
 708                 err = -EFAULT;
 709                 if (put_user(po->pppoe_dev->mtu -
 710                              sizeof(struct pppoe_hdr) -
 711                              PPP_HDRLEN,
 712                              (int *) arg))
 713                         break;
 714                 err = 0;
 715                 break;
 716
 717         case PPPIOCSMRU:
 718                 err = -ENXIO;
 719                 if (!(sk->state & PPPOX_CONNECTED))
 720                         break;
 721
 722                 err = -EFAULT;
 723                 if (get_user(val,(int *) arg))
 724                         break;
 725
 726                 if (val < (po->pppoe_dev->mtu
 727                            - sizeof(struct pppoe_hdr)
 728                            - PPP_HDRLEN))
 729                         err = 0;
 730                 else
 731                         err = -EINVAL;
 732                 break;
 733
 734         case PPPIOCSFLAGS:
 735                 err = -EFAULT;
 736                 if (get_user(val, (int *) arg))
 737                         break;
 738                 err = 0;
 739                 break;
 740
 741         case PPPOEIOCSFWD:
 742         {
 743                 struct pppox_opt *relay_po;
 744
 745                 err = -EBUSY;
 746                 if (sk->state & (PPPOX_BOUND|PPPOX_ZOMBIE|PPPOX_DEAD))
 747                         break;
 748
 749                 err = -ENOTCONN;
 750                 if (!(sk->state & PPPOX_CONNECTED))
 751                         break;
 752
 753                 /* PPPoE address from the user specifies an outbound
 754                    PPPoE address to which frames are forwarded to */
 755                 err = -EFAULT;
 756                 if (copy_from_user(&po->pppoe_relay,
 757                                    (void*)arg,
 758                                    sizeof(struct sockaddr_pppox)))
 759                         break;
 760
 761                 err = -EINVAL;
 762                 if (po->pppoe_relay.sa_family != AF_PPPOX ||
 763                     po->pppoe_relay.sa_protocol!= PX_PROTO_OE)
 764                         break;
 765
 766                 /* Check that the socket referenced by the address
 767                    actually exists. */
 768                 relay_po = get_item_by_addr(&po->pppoe_relay);
 769
 770                 if (!relay_po)
 771                         break;
 772
 773                 sock_put(relay_po->sk);
 774                 sk->state |= PPPOX_RELAY;
 775                 err = 0;
 776                 break;
 777         }
 778
 779         case PPPOEIOCDFWD:
 780                 err = -EALREADY;
 781                 if (!(sk->state & PPPOX_RELAY))
 782                         break;
 783
 784                 sk->state &= ~PPPOX_RELAY;
 785                 err = 0;
 786                 break;
 787
 788         default:;
 789         };
 790
 791         return err;
 792 }
 793
 794
 795 int pppoe_sendmsg(struct socket *sock, struct msghdr *m,
 796                   int total_len, struct scm_cookie *scm)
 797 {
 798         struct sk_buff *skb = NULL;
 799         struct sock *sk = sock->sk;
 800         int error = 0;
 801         struct pppoe_hdr hdr;
 802         struct pppoe_hdr *ph;
 803         struct net_device *dev;
 804         char *start;
 805
 806         if (sk->dead || !(sk->state & PPPOX_CONNECTED)) {
 807                 error = -ENOTCONN;
 808                 goto end;
 809         }
 810
 811         hdr.ver = 1;
 812         hdr.type = 1;
 813         hdr.code = 0;
 814         hdr.sid = sk->num;
 815
 816         lock_sock(sk);
 817
 818         dev = sk->protinfo.pppox->pppoe_dev;
 819
 820         error = -EMSGSIZE;
 821         if (total_len > (dev->mtu + dev->hard_header_len))
 822                 goto end;
 823
 824
 825         skb = sock_wmalloc(sk, total_len + dev->hard_header_len + 32,
 826                            0, GFP_KERNEL);
 827         if (!skb) {
 828                 error = -ENOMEM;
 829                 goto end;
 830         }
 831
 832         /* Reserve space for headers. */
 833         skb_reserve(skb, dev->hard_header_len);
 834         skb->nh.raw = skb->data;
 835
 836         skb->dev = dev;
 837
 838         skb->priority = sk->priority;
 839         skb->protocol = __constant_htons(ETH_P_PPP_SES);
 840
 841         ph = (struct pppoe_hdr *) skb_put(skb, total_len + sizeof(struct pppoe_hdr));
 842         start = (char *) &ph->tag[0];
 843
 844         error = memcpy_fromiovec(start, m->msg_iov, total_len);
 845
 846         if (error < 0) {
 847                 kfree_skb(skb);
 848                 goto end;
 849         }
 850
 851         error = total_len;
 852         dev->hard_header(skb, dev, ETH_P_PPP_SES,
 853                          sk->protinfo.pppox->pppoe_pa.remote,
 854                          NULL, total_len);
 855
 856         memcpy(ph, &hdr, sizeof(struct pppoe_hdr));
 857
 858         ph->length = htons(total_len);
 859
 860         dev_queue_xmit(skb);
 861
 862 end:
 863         release_sock(sk);
 864         return error;
 865 }
 866
 867
 868 /************************************************************************
 869  *
 870  * xmit function for internal use.
 871  *
 872  ***********************************************************************/
 873 int __pppoe_xmit(struct sock *sk, struct sk_buff *skb)
 874 {
 875         struct net_device *dev = sk->protinfo.pppox->pppoe_dev;
 876         struct pppoe_hdr hdr;
 877         struct pppoe_hdr *ph;
 878         int headroom = skb_headroom(skb);
 879         int data_len = skb->len;
 880         struct sk_buff *skb2;
 881
 882         if (sk->dead  || !(sk->state & PPPOX_CONNECTED))
 883                 goto abort;
 884
 885         hdr.ver = 1;
 886         hdr.type = 1;
 887         hdr.code = 0;
 888         hdr.sid = sk->num;
 889         hdr.length = htons(skb->len);
 890
 891         if (!dev)
 892                 goto abort;
 893
 894         /* Copy the skb if there is no space for the header. */
 895         if (headroom < (sizeof(struct pppoe_hdr) + dev->hard_header_len)) {
 896                 skb2 = dev_alloc_skb(32+skb->len +
 897                                      sizeof(struct pppoe_hdr) +
 898                                      dev->hard_header_len);
 899
 900                 if (skb2 == NULL)
 901                         goto abort;
 902
 903                 skb_reserve(skb2, dev->hard_header_len + sizeof(struct pppoe_hdr));
 904                 memcpy(skb_put(skb2, skb->len), skb->data, skb->len);
 905         } else {
 906                 /* Make a clone so as to not disturb the original skb,
 907                  * give dev_queue_xmit something it can free.
 908                  */
 909                 skb2 = skb_clone(skb, GFP_ATOMIC);
 910
 911                 if (skb2 == NULL)
 912                         goto abort;
 913         }
 914
 915         ph = (struct pppoe_hdr *) skb_push(skb2, sizeof(struct pppoe_hdr));
 916         memcpy(ph, &hdr, sizeof(struct pppoe_hdr));
 917         skb2->protocol = __constant_htons(ETH_P_PPP_SES);
 918
 919         skb2->nh.raw = skb2->data;
 920
 921         skb2->dev = dev;
 922
 923         dev->hard_header(skb2, dev, ETH_P_PPP_SES,
 924                          sk->protinfo.pppox->pppoe_pa.remote,
 925                          NULL, data_len);
 926
 927         /* We're transmitting skb2, and assuming that dev_queue_xmit
 928          * will free it.  The generic ppp layer however, is expecting
 929          * that we give back 'skb' (not 'skb2') in case of failure,
 930          * but free it in case of success.
 931          */
 932
 933         if (dev_queue_xmit(skb2) < 0)
 934                 goto abort;
 935
 936         kfree_skb(skb);
 937         return 1;
 938
 939 abort:
 940         return 0;
 941 }
 942
 943
 944 /************************************************************************
 945  *
 946  * xmit function called by generic PPP driver
 947  * sends PPP frame over PPPoE socket
 948  *
 949  ***********************************************************************/
 950 int pppoe_xmit(struct ppp_channel *chan, struct sk_buff *skb)
 951 {
 952         struct sock *sk = (struct sock *) chan->private;
 953         return __pppoe_xmit(sk, skb);
 954 }
 955
 956
 957 struct ppp_channel_ops pppoe_chan_ops = { pppoe_xmit , NULL };
 958
 959 int pppoe_rcvmsg(struct socket *sock, struct msghdr *m, int total_len, int flags, struct scm_cookie *scm)
 960 {
 961         struct sock *sk = sock->sk;
 962         struct sk_buff *skb = NULL;
 963         int error = 0;
 964
 965         if (sk->state & PPPOX_BOUND) {
 966                 error = -EIO;
 967                 goto end;
 968         }
 969
 970         skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
 971                                 flags & MSG_DONTWAIT, &error);
 972
 973         if (error < 0) {
 974                 goto end;
 975         }
 976
 977         m->msg_namelen = 0;
 978
 979         if (skb) {
 980                 total_len = min_t(int, total_len, skb->len);
 981                 error = skb_copy_datagram_iovec(skb, 0, m->msg_iov, total_len);
 982                 if (error == 0)
 983                         error = total_len;
 984         }
 985
 986         if (skb)
 987                 kfree_skb(skb);
 988 end:
 989         return error;
 990 }
 991
 992 int pppoe_proc_info(char *buffer, char **start, off_t offset, int length)
 993 {
 994         struct pppox_opt *po;
 995         int len = 0;
 996         off_t pos = 0;
 997         off_t begin = 0;
 998         int size;
 999         int i;
1000
1001         len += sprintf(buffer,
1002                        "Id       Address              Device\n");
1003         pos = len;
1004
1005         write_lock_bh(&pppoe_hash_lock);
1006
1007         for (i = 0; i < PPPOE_HASH_SIZE; i++) {
1008                 po = item_hash_table[i];
1009                 while (po) {
1010                         char *dev = po->pppoe_pa.dev;
1011
1012                         size = sprintf(buffer + len,
1013                                        "%08X %02X:%02X:%02X:%02X:%02X:%02X %8s\n",
1014                                        po->pppoe_pa.sid,
1015                                        po->pppoe_pa.remote[0],
1016                                        po->pppoe_pa.remote[1],
1017                                        po->pppoe_pa.remote[2],
1018                                        po->pppoe_pa.remote[3],
1019                                        po->pppoe_pa.remote[4],
1020                                        po->pppoe_pa.remote[5],
1021                                        dev);
1022                         len += size;
1023                         pos += size;
1024                         if (pos < offset) {
1025                                 len = 0;
1026                                 begin = pos;
1027                         }
1028
1029                         if (pos > offset + length)
1030                                 break;
1031
1032                         po = po->next;
1033                 }
1034
1035                 if (po)
1036                         break;
1037         }
1038         write_unlock_bh(&pppoe_hash_lock);
1039
1040         *start = buffer + (offset - begin);
1041         len -= (offset - begin);
1042         if (len > length)
1043                 len = length;
1044         if (len < 0)
1045                 len = 0;
1046         return len;
1047 }
1048
1049
1050 struct proto_ops pppoe_ops = {
1051     family:             AF_PPPOX,
1052     release:            pppoe_release,
1053     bind:               sock_no_bind,
1054     connect:            pppoe_connect,
1055     socketpair:         sock_no_socketpair,
1056     accept:             sock_no_accept,
1057     getname:            pppoe_getname,
1058     poll:               datagram_poll,
1059     ioctl:              pppoe_ioctl,
1060     listen:             sock_no_listen,
1061     shutdown:           sock_no_shutdown,
1062     setsockopt:         sock_no_setsockopt,
1063     getsockopt:         sock_no_getsockopt,
1064     sendmsg:            pppoe_sendmsg,
1065     recvmsg:            pppoe_rcvmsg,
1066     mmap:               sock_no_mmap
1067 };
1068
1069 struct pppox_proto pppoe_proto = {
1070     create:     pppoe_create,
1071     ioctl:      pppoe_ioctl
1072 };
1073
1074
1075 int __init pppoe_init(void)
1076 {
1077         int err = register_pppox_proto(PX_PROTO_OE, &pppoe_proto);
1078
1079         if (err == 0) {
1080                 dev_add_pack(&pppoes_ptype);
1081                 dev_add_pack(&pppoed_ptype);
1082                 register_netdevice_notifier(&pppoe_notifier);
1083                 proc_net_create("pppoe", 0, pppoe_proc_info);
1084         }
1085         return err;
1086 }
1087
1088 void __exit pppoe_exit(void)
1089 {
1090         unregister_pppox_proto(PX_PROTO_OE);
1091         dev_remove_pack(&pppoes_ptype);
1092         dev_remove_pack(&pppoed_ptype);
1093         unregister_netdevice_notifier(&pppoe_notifier);
1094         proc_net_remove("pppoe");
1095 }
1096
1097 module_init(pppoe_init);
1098 module_exit(pppoe_exit);
1099
1100 MODULE_AUTHOR("Michal Ostrowski <mostrows@speakeasy.net>");
1101 MODULE_DESCRIPTION("PPP over Ethernet driver");
1102 MODULE_LICENSE("GPL");