git.oblomov.eu Git - linux-2.6/blob - net/packet/af_packet.c

   1 /*
   2  * INET         An implementation of the TCP/IP protocol suite for the LINUX
   3  *              operating system.  INET is implemented using the  BSD Socket
   4  *              interface as the means of communication with the user level.
   5  *
   6  *              PACKET - implements raw packet sockets.
   7  *
   8  * Version:     $Id: af_packet.c,v 1.61 2002/02/08 03:57:19 davem Exp $
   9  *
  10  * Authors:     Ross Biro
  11  *              Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  12  *              Alan Cox, <gw4pts@gw4pts.ampr.org>
  13  *
  14  * Fixes:
  15  *              Alan Cox        :       verify_area() now used correctly
  16  *              Alan Cox        :       new skbuff lists, look ma no backlogs!
  17  *              Alan Cox        :       tidied skbuff lists.
  18  *              Alan Cox        :       Now uses generic datagram routines I
  19  *                                      added. Also fixed the peek/read crash
  20  *                                      from all old Linux datagram code.
  21  *              Alan Cox        :       Uses the improved datagram code.
  22  *              Alan Cox        :       Added NULL's for socket options.
  23  *              Alan Cox        :       Re-commented the code.
  24  *              Alan Cox        :       Use new kernel side addressing
  25  *              Rob Janssen     :       Correct MTU usage.
  26  *              Dave Platt      :       Counter leaks caused by incorrect
  27  *                                      interrupt locking and some slightly
  28  *                                      dubious gcc output. Can you read
  29  *                                      compiler: it said _VOLATILE_
  30  *      Richard Kooijman        :       Timestamp fixes.
  31  *              Alan Cox        :       New buffers. Use sk->mac.raw.
  32  *              Alan Cox        :       sendmsg/recvmsg support.
  33  *              Alan Cox        :       Protocol setting support
  34  *      Alexey Kuznetsov        :       Untied from IPv4 stack.
  35  *      Cyrus Durgin            :       Fixed kerneld for kmod.
  36  *      Michal Ostrowski        :       Module initialization cleanup.
  37  *         Ulises Alonso        :       Frame number limit removal and
  38  *                                      packet_set_ring memory leak.
  39  *              Eric Biederman  :       Allow for > 8 byte hardware addresses.
  40  *                                      The convention is that longer addresses
  41  *                                      will simply extend the hardware address
  42  *                                      byte arrays at the end of sockaddr_ll
  43  *                                      and packet_mreq.
  44  *
  45  *              This program is free software; you can redistribute it and/or
  46  *              modify it under the terms of the GNU General Public License
  47  *              as published by the Free Software Foundation; either version
  48  *              2 of the License, or (at your option) any later version.
  49  *
  50  */
  51
  52 #include <linux/types.h>
  53 #include <linux/sched.h>
  54 #include <linux/mm.h>
  55 #include <linux/capability.h>
  56 #include <linux/fcntl.h>
  57 #include <linux/socket.h>
  58 #include <linux/in.h>
  59 #include <linux/inet.h>
  60 #include <linux/netdevice.h>
  61 #include <linux/if_packet.h>
  62 #include <linux/wireless.h>
  63 #include <linux/kmod.h>
  64 #include <net/ip.h>
  65 #include <net/protocol.h>
  66 #include <linux/skbuff.h>
  67 #include <net/sock.h>
  68 #include <linux/errno.h>
  69 #include <linux/timer.h>
  70 #include <asm/system.h>
  71 #include <asm/uaccess.h>
  72 #include <asm/ioctls.h>
  73 #include <asm/page.h>
  74 #include <asm/io.h>
  75 #include <linux/proc_fs.h>
  76 #include <linux/seq_file.h>
  77 #include <linux/poll.h>
  78 #include <linux/module.h>
  79 #include <linux/init.h>
  80
  81 #ifdef CONFIG_INET
  82 #include <net/inet_common.h>
  83 #endif
  84
  85 #define CONFIG_SOCK_PACKET      1
  86
  87 /*
  88    Proposed replacement for SIOC{ADD,DEL}MULTI and
  89    IFF_PROMISC, IFF_ALLMULTI flags.
  90
  91    It is more expensive, but I believe,
  92    it is really correct solution: reentereble, safe and fault tolerant.
  93
  94    IFF_PROMISC/IFF_ALLMULTI/SIOC{ADD/DEL}MULTI are faked by keeping
  95    reference count and global flag, so that real status is
  96    (gflag|(count != 0)), so that we can use obsolete faulty interface
  97    not harming clever users.
  98  */
  99 #define CONFIG_PACKET_MULTICAST 1
 100
 101 /*
 102    Assumptions:
 103    - if device has no dev->hard_header routine, it adds and removes ll header
 104      inside itself. In this case ll header is invisible outside of device,
 105      but higher levels still should reserve dev->hard_header_len.
 106      Some devices are enough clever to reallocate skb, when header
 107      will not fit to reserved space (tunnel), another ones are silly
 108      (PPP).
 109    - packet socket receives packets with pulled ll header,
 110      so that SOCK_RAW should push it back.
 111
 112 On receive:
 113 -----------
 114
 115 Incoming, dev->hard_header!=NULL
 116    mac.raw -> ll header
 117    data    -> data
 118
 119 Outgoing, dev->hard_header!=NULL
 120    mac.raw -> ll header
 121    data    -> ll header
 122
 123 Incoming, dev->hard_header==NULL
 124    mac.raw -> UNKNOWN position. It is very likely, that it points to ll header.
 125               PPP makes it, that is wrong, because introduce assymetry
 126               between rx and tx paths.
 127    data    -> data
 128
 129 Outgoing, dev->hard_header==NULL
 130    mac.raw -> data. ll header is still not built!
 131    data    -> data
 132
 133 Resume
 134   If dev->hard_header==NULL we are unlikely to restore sensible ll header.
 135
 136
 137 On transmit:
 138 ------------
 139
 140 dev->hard_header != NULL
 141    mac.raw -> ll header
 142    data    -> ll header
 143
 144 dev->hard_header == NULL (ll header is added by device, we cannot control it)
 145    mac.raw -> data
 146    data -> data
 147
 148    We should set nh.raw on output to correct posistion,
 149    packet classifier depends on it.
 150  */
 151
 152 /* List of all packet sockets. */
 153 static HLIST_HEAD(packet_sklist);
 154 static DEFINE_RWLOCK(packet_sklist_lock);
 155
 156 static atomic_t packet_socks_nr;
 157
 158
 159 /* Private packet socket structures. */
 160
 161 #ifdef CONFIG_PACKET_MULTICAST
 162 struct packet_mclist
 163 {
 164         struct packet_mclist    *next;
 165         int                     ifindex;
 166         int                     count;
 167         unsigned short          type;
 168         unsigned short          alen;
 169         unsigned char           addr[MAX_ADDR_LEN];
 170 };
 171 /* identical to struct packet_mreq except it has
 172  * a longer address field.
 173  */
 174 struct packet_mreq_max
 175 {
 176         int             mr_ifindex;
 177         unsigned short  mr_type;
 178         unsigned short  mr_alen;
 179         unsigned char   mr_address[MAX_ADDR_LEN];
 180 };
 181 #endif
 182 #ifdef CONFIG_PACKET_MMAP
 183 static int packet_set_ring(struct sock *sk, struct tpacket_req *req, int closing);
 184 #endif
 185
 186 static void packet_flush_mclist(struct sock *sk);
 187
 188 struct packet_sock {
 189         /* struct sock has to be the first member of packet_sock */
 190         struct sock             sk;
 191         struct tpacket_stats    stats;
 192 #ifdef CONFIG_PACKET_MMAP
 193         char *                  *pg_vec;
 194         unsigned int            head;
 195         unsigned int            frames_per_block;
 196         unsigned int            frame_size;
 197         unsigned int            frame_max;
 198         int                     copy_thresh;
 199 #endif
 200         struct packet_type      prot_hook;
 201         spinlock_t              bind_lock;
 202         char                    running;        /* prot_hook is attached*/
 203         int                     ifindex;        /* bound device         */
 204         unsigned short          num;
 205 #ifdef CONFIG_PACKET_MULTICAST
 206         struct packet_mclist    *mclist;
 207 #endif
 208 #ifdef CONFIG_PACKET_MMAP
 209         atomic_t                mapped;
 210         unsigned int            pg_vec_order;
 211         unsigned int            pg_vec_pages;
 212         unsigned int            pg_vec_len;
 213 #endif
 214 };
 215
 216 #ifdef CONFIG_PACKET_MMAP
 217
 218 static inline char *packet_lookup_frame(struct packet_sock *po, unsigned int position)
 219 {
 220         unsigned int pg_vec_pos, frame_offset;
 221         char *frame;
 222
 223         pg_vec_pos = position / po->frames_per_block;
 224         frame_offset = position % po->frames_per_block;
 225
 226         frame = po->pg_vec[pg_vec_pos] + (frame_offset * po->frame_size);
 227
 228         return frame;
 229 }
 230 #endif
 231
 232 static inline struct packet_sock *pkt_sk(struct sock *sk)
 233 {
 234         return (struct packet_sock *)sk;
 235 }
 236
 237 static void packet_sock_destruct(struct sock *sk)
 238 {
 239         BUG_TRAP(!atomic_read(&sk->sk_rmem_alloc));
 240         BUG_TRAP(!atomic_read(&sk->sk_wmem_alloc));
 241
 242         if (!sock_flag(sk, SOCK_DEAD)) {
 243                 printk("Attempt to release alive packet socket: %p\n", sk);
 244                 return;
 245         }
 246
 247         atomic_dec(&packet_socks_nr);
 248 #ifdef PACKET_REFCNT_DEBUG
 249         printk(KERN_DEBUG "PACKET socket %p is free, %d are alive\n", sk, atomic_read(&packet_socks_nr));
 250 #endif
 251 }
 252
 253
 254 static const struct proto_ops packet_ops;
 255
 256 #ifdef CONFIG_SOCK_PACKET
 257 static const struct proto_ops packet_ops_spkt;
 258
 259 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,  struct packet_type *pt, struct net_device *orig_dev)
 260 {
 261         struct sock *sk;
 262         struct sockaddr_pkt *spkt;
 263
 264         /*
 265          *      When we registered the protocol we saved the socket in the data
 266          *      field for just this event.
 267          */
 268
 269         sk = pt->af_packet_priv;
 270
 271         /*
 272          *      Yank back the headers [hope the device set this
 273          *      right or kerboom...]
 274          *
 275          *      Incoming packets have ll header pulled,
 276          *      push it back.
 277          *
 278          *      For outgoing ones skb->data == skb->mac.raw
 279          *      so that this procedure is noop.
 280          */
 281
 282         if (skb->pkt_type == PACKET_LOOPBACK)
 283                 goto out;
 284
 285         if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
 286                 goto oom;
 287
 288         /* drop any routing info */
 289         dst_release(skb->dst);
 290         skb->dst = NULL;
 291
 292         /* drop conntrack reference */
 293         nf_reset(skb);
 294
 295         spkt = (struct sockaddr_pkt*)skb->cb;
 296
 297         skb_push(skb, skb->data-skb->mac.raw);
 298
 299         /*
 300          *      The SOCK_PACKET socket receives _all_ frames.
 301          */
 302
 303         spkt->spkt_family = dev->type;
 304         strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
 305         spkt->spkt_protocol = skb->protocol;
 306
 307         /*
 308          *      Charge the memory to the socket. This is done specifically
 309          *      to prevent sockets using all the memory up.
 310          */
 311
 312         if (sock_queue_rcv_skb(sk,skb) == 0)
 313                 return 0;
 314
 315 out:
 316         kfree_skb(skb);
 317 oom:
 318         return 0;
 319 }
 320
 321
 322 /*
 323  *      Output a raw packet to a device layer. This bypasses all the other
 324  *      protocol layers and you must therefore supply it with a complete frame
 325  */
 326
 327 static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
 328                                struct msghdr *msg, size_t len)
 329 {
 330         struct sock *sk = sock->sk;
 331         struct sockaddr_pkt *saddr=(struct sockaddr_pkt *)msg->msg_name;
 332         struct sk_buff *skb;
 333         struct net_device *dev;
 334         unsigned short proto=0;
 335         int err;
 336
 337         /*
 338          *      Get and verify the address.
 339          */
 340
 341         if (saddr)
 342         {
 343                 if (msg->msg_namelen < sizeof(struct sockaddr))
 344                         return(-EINVAL);
 345                 if (msg->msg_namelen==sizeof(struct sockaddr_pkt))
 346                         proto=saddr->spkt_protocol;
 347         }
 348         else
 349                 return(-ENOTCONN);      /* SOCK_PACKET must be sent giving an address */
 350
 351         /*
 352          *      Find the device first to size check it
 353          */
 354
 355         saddr->spkt_device[13] = 0;
 356         dev = dev_get_by_name(saddr->spkt_device);
 357         err = -ENODEV;
 358         if (dev == NULL)
 359                 goto out_unlock;
 360
 361         /*
 362          *      You may not queue a frame bigger than the mtu. This is the lowest level
 363          *      raw protocol and you must do your own fragmentation at this level.
 364          */
 365
 366         err = -EMSGSIZE;
 367         if (len > dev->mtu + dev->hard_header_len)
 368                 goto out_unlock;
 369
 370         err = -ENOBUFS;
 371         skb = sock_wmalloc(sk, len + LL_RESERVED_SPACE(dev), 0, GFP_KERNEL);
 372
 373         /*
 374          *      If the write buffer is full, then tough. At this level the user gets to
 375          *      deal with the problem - do your own algorithmic backoffs. That's far
 376          *      more flexible.
 377          */
 378
 379         if (skb == NULL)
 380                 goto out_unlock;
 381
 382         /*
 383          *      Fill it in
 384          */
 385
 386         /* FIXME: Save some space for broken drivers that write a
 387          * hard header at transmission time by themselves. PPP is the
 388          * notable one here. This should really be fixed at the driver level.
 389          */
 390         skb_reserve(skb, LL_RESERVED_SPACE(dev));
 391         skb->nh.raw = skb->data;
 392
 393         /* Try to align data part correctly */
 394         if (dev->hard_header) {
 395                 skb->data -= dev->hard_header_len;
 396                 skb->tail -= dev->hard_header_len;
 397                 if (len < dev->hard_header_len)
 398                         skb->nh.raw = skb->data;
 399         }
 400
 401         /* Returns -EFAULT on error */
 402         err = memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len);
 403         skb->protocol = proto;
 404         skb->dev = dev;
 405         skb->priority = sk->sk_priority;
 406         if (err)
 407                 goto out_free;
 408
 409         err = -ENETDOWN;
 410         if (!(dev->flags & IFF_UP))
 411                 goto out_free;
 412
 413         /*
 414          *      Now send it
 415          */
 416
 417         dev_queue_xmit(skb);
 418         dev_put(dev);
 419         return(len);
 420
 421 out_free:
 422         kfree_skb(skb);
 423 out_unlock:
 424         if (dev)
 425                 dev_put(dev);
 426         return err;
 427 }
 428 #endif
 429
 430 static inline unsigned run_filter(struct sk_buff *skb, struct sock *sk, unsigned res)
 431 {
 432         struct sk_filter *filter;
 433
 434         bh_lock_sock(sk);
 435         filter = sk->sk_filter;
 436         /*
 437          * Our caller already checked that filter != NULL but we need to
 438          * verify that under bh_lock_sock() to be safe
 439          */
 440         if (likely(filter != NULL))
 441                 res = sk_run_filter(skb, filter->insns, filter->len);
 442         bh_unlock_sock(sk);
 443
 444         return res;
 445 }
 446
 447 /*
 448    This function makes lazy skb cloning in hope that most of packets
 449    are discarded by BPF.
 450
 451    Note tricky part: we DO mangle shared skb! skb->data, skb->len
 452    and skb->cb are mangled. It works because (and until) packets
 453    falling here are owned by current CPU. Output packets are cloned
 454    by dev_queue_xmit_nit(), input packets are processed by net_bh
 455    sequencially, so that if we return skb to original state on exit,
 456    we will not harm anyone.
 457  */
 458
 459 static int packet_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
 460 {
 461         struct sock *sk;
 462         struct sockaddr_ll *sll;
 463         struct packet_sock *po;
 464         u8 * skb_head = skb->data;
 465         int skb_len = skb->len;
 466         unsigned snaplen;
 467
 468         if (skb->pkt_type == PACKET_LOOPBACK)
 469                 goto drop;
 470
 471         sk = pt->af_packet_priv;
 472         po = pkt_sk(sk);
 473
 474         skb->dev = dev;
 475
 476         if (dev->hard_header) {
 477                 /* The device has an explicit notion of ll header,
 478                    exported to higher levels.
 479
 480                    Otherwise, the device hides datails of it frame
 481                    structure, so that corresponding packet head
 482                    never delivered to user.
 483                  */
 484                 if (sk->sk_type != SOCK_DGRAM)
 485                         skb_push(skb, skb->data - skb->mac.raw);
 486                 else if (skb->pkt_type == PACKET_OUTGOING) {
 487                         /* Special case: outgoing packets have ll header at head */
 488                         skb_pull(skb, skb->nh.raw - skb->data);
 489                 }
 490         }
 491
 492         snaplen = skb->len;
 493
 494         if (sk->sk_filter) {
 495                 unsigned res = run_filter(skb, sk, snaplen);
 496                 if (res == 0)
 497                         goto drop_n_restore;
 498                 if (snaplen > res)
 499                         snaplen = res;
 500         }
 501
 502         if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
 503             (unsigned)sk->sk_rcvbuf)
 504                 goto drop_n_acct;
 505
 506         if (skb_shared(skb)) {
 507                 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
 508                 if (nskb == NULL)
 509                         goto drop_n_acct;
 510
 511                 if (skb_head != skb->data) {
 512                         skb->data = skb_head;
 513                         skb->len = skb_len;
 514                 }
 515                 kfree_skb(skb);
 516                 skb = nskb;
 517         }
 518
 519         sll = (struct sockaddr_ll*)skb->cb;
 520         sll->sll_family = AF_PACKET;
 521         sll->sll_hatype = dev->type;
 522         sll->sll_protocol = skb->protocol;
 523         sll->sll_pkttype = skb->pkt_type;
 524         sll->sll_ifindex = dev->ifindex;
 525         sll->sll_halen = 0;
 526
 527         if (dev->hard_header_parse)
 528                 sll->sll_halen = dev->hard_header_parse(skb, sll->sll_addr);
 529
 530         if (pskb_trim(skb, snaplen))
 531                 goto drop_n_acct;
 532
 533         skb_set_owner_r(skb, sk);
 534         skb->dev = NULL;
 535         dst_release(skb->dst);
 536         skb->dst = NULL;
 537
 538         /* drop conntrack reference */
 539         nf_reset(skb);
 540
 541         spin_lock(&sk->sk_receive_queue.lock);
 542         po->stats.tp_packets++;
 543         __skb_queue_tail(&sk->sk_receive_queue, skb);
 544         spin_unlock(&sk->sk_receive_queue.lock);
 545         sk->sk_data_ready(sk, skb->len);
 546         return 0;
 547
 548 drop_n_acct:
 549         spin_lock(&sk->sk_receive_queue.lock);
 550         po->stats.tp_drops++;
 551         spin_unlock(&sk->sk_receive_queue.lock);
 552
 553 drop_n_restore:
 554         if (skb_head != skb->data && skb_shared(skb)) {
 555                 skb->data = skb_head;
 556                 skb->len = skb_len;
 557         }
 558 drop:
 559         kfree_skb(skb);
 560         return 0;
 561 }
 562
 563 #ifdef CONFIG_PACKET_MMAP
 564 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
 565 {
 566         struct sock *sk;
 567         struct packet_sock *po;
 568         struct sockaddr_ll *sll;
 569         struct tpacket_hdr *h;
 570         u8 * skb_head = skb->data;
 571         int skb_len = skb->len;
 572         unsigned snaplen;
 573         unsigned long status = TP_STATUS_LOSING|TP_STATUS_USER;
 574         unsigned short macoff, netoff;
 575         struct sk_buff *copy_skb = NULL;
 576
 577         if (skb->pkt_type == PACKET_LOOPBACK)
 578                 goto drop;
 579
 580         sk = pt->af_packet_priv;
 581         po = pkt_sk(sk);
 582
 583         if (dev->hard_header) {
 584                 if (sk->sk_type != SOCK_DGRAM)
 585                         skb_push(skb, skb->data - skb->mac.raw);
 586                 else if (skb->pkt_type == PACKET_OUTGOING) {
 587                         /* Special case: outgoing packets have ll header at head */
 588                         skb_pull(skb, skb->nh.raw - skb->data);
 589                         if (skb->ip_summed == CHECKSUM_HW)
 590                                 status |= TP_STATUS_CSUMNOTREADY;
 591                 }
 592         }
 593
 594         snaplen = skb->len;
 595
 596         if (sk->sk_filter) {
 597                 unsigned res = run_filter(skb, sk, snaplen);
 598                 if (res == 0)
 599                         goto drop_n_restore;
 600                 if (snaplen > res)
 601                         snaplen = res;
 602         }
 603
 604         if (sk->sk_type == SOCK_DGRAM) {
 605                 macoff = netoff = TPACKET_ALIGN(TPACKET_HDRLEN) + 16;
 606         } else {
 607                 unsigned maclen = skb->nh.raw - skb->data;
 608                 netoff = TPACKET_ALIGN(TPACKET_HDRLEN + (maclen < 16 ? 16 : maclen));
 609                 macoff = netoff - maclen;
 610         }
 611
 612         if (macoff + snaplen > po->frame_size) {
 613                 if (po->copy_thresh &&
 614                     atomic_read(&sk->sk_rmem_alloc) + skb->truesize <
 615                     (unsigned)sk->sk_rcvbuf) {
 616                         if (skb_shared(skb)) {
 617                                 copy_skb = skb_clone(skb, GFP_ATOMIC);
 618                         } else {
 619                                 copy_skb = skb_get(skb);
 620                                 skb_head = skb->data;
 621                         }
 622                         if (copy_skb)
 623                                 skb_set_owner_r(copy_skb, sk);
 624                 }
 625                 snaplen = po->frame_size - macoff;
 626                 if ((int)snaplen < 0)
 627                         snaplen = 0;
 628         }
 629         if (snaplen > skb->len-skb->data_len)
 630                 snaplen = skb->len-skb->data_len;
 631
 632         spin_lock(&sk->sk_receive_queue.lock);
 633         h = (struct tpacket_hdr *)packet_lookup_frame(po, po->head);
 634
 635         if (h->tp_status)
 636                 goto ring_is_full;
 637         po->head = po->head != po->frame_max ? po->head+1 : 0;
 638         po->stats.tp_packets++;
 639         if (copy_skb) {
 640                 status |= TP_STATUS_COPY;
 641                 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
 642         }
 643         if (!po->stats.tp_drops)
 644                 status &= ~TP_STATUS_LOSING;
 645         spin_unlock(&sk->sk_receive_queue.lock);
 646
 647         memcpy((u8*)h + macoff, skb->data, snaplen);
 648
 649         h->tp_len = skb->len;
 650         h->tp_snaplen = snaplen;
 651         h->tp_mac = macoff;
 652         h->tp_net = netoff;
 653         if (skb->tstamp.off_sec == 0) {
 654                 __net_timestamp(skb);
 655                 sock_enable_timestamp(sk);
 656         }
 657         h->tp_sec = skb->tstamp.off_sec;
 658         h->tp_usec = skb->tstamp.off_usec;
 659
 660         sll = (struct sockaddr_ll*)((u8*)h + TPACKET_ALIGN(sizeof(*h)));
 661         sll->sll_halen = 0;
 662         if (dev->hard_header_parse)
 663                 sll->sll_halen = dev->hard_header_parse(skb, sll->sll_addr);
 664         sll->sll_family = AF_PACKET;
 665         sll->sll_hatype = dev->type;
 666         sll->sll_protocol = skb->protocol;
 667         sll->sll_pkttype = skb->pkt_type;
 668         sll->sll_ifindex = dev->ifindex;
 669
 670         h->tp_status = status;
 671         mb();
 672
 673         {
 674                 struct page *p_start, *p_end;
 675                 u8 *h_end = (u8 *)h + macoff + snaplen - 1;
 676
 677                 p_start = virt_to_page(h);
 678                 p_end = virt_to_page(h_end);
 679                 while (p_start <= p_end) {
 680                         flush_dcache_page(p_start);
 681                         p_start++;
 682                 }
 683         }
 684
 685         sk->sk_data_ready(sk, 0);
 686
 687 drop_n_restore:
 688         if (skb_head != skb->data && skb_shared(skb)) {
 689                 skb->data = skb_head;
 690                 skb->len = skb_len;
 691         }
 692 drop:
 693         kfree_skb(skb);
 694         return 0;
 695
 696 ring_is_full:
 697         po->stats.tp_drops++;
 698         spin_unlock(&sk->sk_receive_queue.lock);
 699
 700         sk->sk_data_ready(sk, 0);
 701         if (copy_skb)
 702                 kfree_skb(copy_skb);
 703         goto drop_n_restore;
 704 }
 705
 706 #endif
 707
 708
 709 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
 710                           struct msghdr *msg, size_t len)
 711 {
 712         struct sock *sk = sock->sk;
 713         struct sockaddr_ll *saddr=(struct sockaddr_ll *)msg->msg_name;
 714         struct sk_buff *skb;
 715         struct net_device *dev;
 716         unsigned short proto;
 717         unsigned char *addr;
 718         int ifindex, err, reserve = 0;
 719
 720         /*
 721          *      Get and verify the address.
 722          */
 723
 724         if (saddr == NULL) {
 725                 struct packet_sock *po = pkt_sk(sk);
 726
 727                 ifindex = po->ifindex;
 728                 proto   = po->num;
 729                 addr    = NULL;
 730         } else {
 731                 err = -EINVAL;
 732                 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
 733                         goto out;
 734                 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
 735                         goto out;
 736                 ifindex = saddr->sll_ifindex;
 737                 proto   = saddr->sll_protocol;
 738                 addr    = saddr->sll_addr;
 739         }
 740
 741
 742         dev = dev_get_by_index(ifindex);
 743         err = -ENXIO;
 744         if (dev == NULL)
 745                 goto out_unlock;
 746         if (sock->type == SOCK_RAW)
 747                 reserve = dev->hard_header_len;
 748
 749         err = -EMSGSIZE;
 750         if (len > dev->mtu+reserve)
 751                 goto out_unlock;
 752
 753         skb = sock_alloc_send_skb(sk, len + LL_RESERVED_SPACE(dev),
 754                                 msg->msg_flags & MSG_DONTWAIT, &err);
 755         if (skb==NULL)
 756                 goto out_unlock;
 757
 758         skb_reserve(skb, LL_RESERVED_SPACE(dev));
 759         skb->nh.raw = skb->data;
 760
 761         if (dev->hard_header) {
 762                 int res;
 763                 err = -EINVAL;
 764                 res = dev->hard_header(skb, dev, ntohs(proto), addr, NULL, len);
 765                 if (sock->type != SOCK_DGRAM) {
 766                         skb->tail = skb->data;
 767                         skb->len = 0;
 768                 } else if (res < 0)
 769                         goto out_free;
 770         }
 771
 772         /* Returns -EFAULT on error */
 773         err = memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len);
 774         if (err)
 775                 goto out_free;
 776
 777         skb->protocol = proto;
 778         skb->dev = dev;
 779         skb->priority = sk->sk_priority;
 780
 781         err = -ENETDOWN;
 782         if (!(dev->flags & IFF_UP))
 783                 goto out_free;
 784
 785         /*
 786          *      Now send it
 787          */
 788
 789         err = dev_queue_xmit(skb);
 790         if (err > 0 && (err = net_xmit_errno(err)) != 0)
 791                 goto out_unlock;
 792
 793         dev_put(dev);
 794
 795         return(len);
 796
 797 out_free:
 798         kfree_skb(skb);
 799 out_unlock:
 800         if (dev)
 801                 dev_put(dev);
 802 out:
 803         return err;
 804 }
 805
 806 /*
 807  *      Close a PACKET socket. This is fairly simple. We immediately go
 808  *      to 'closed' state and remove our protocol entry in the device list.
 809  */
 810
 811 static int packet_release(struct socket *sock)
 812 {
 813         struct sock *sk = sock->sk;
 814         struct packet_sock *po;
 815
 816         if (!sk)
 817                 return 0;
 818
 819         po = pkt_sk(sk);
 820
 821         write_lock_bh(&packet_sklist_lock);
 822         sk_del_node_init(sk);
 823         write_unlock_bh(&packet_sklist_lock);
 824
 825         /*
 826          *      Unhook packet receive handler.
 827          */
 828
 829         if (po->running) {
 830                 /*
 831                  *      Remove the protocol hook
 832                  */
 833                 dev_remove_pack(&po->prot_hook);
 834                 po->running = 0;
 835                 po->num = 0;
 836                 __sock_put(sk);
 837         }
 838
 839 #ifdef CONFIG_PACKET_MULTICAST
 840         packet_flush_mclist(sk);
 841 #endif
 842
 843 #ifdef CONFIG_PACKET_MMAP
 844         if (po->pg_vec) {
 845                 struct tpacket_req req;
 846                 memset(&req, 0, sizeof(req));
 847                 packet_set_ring(sk, &req, 1);
 848         }
 849 #endif
 850
 851         /*
 852          *      Now the socket is dead. No more input will appear.
 853          */
 854
 855         sock_orphan(sk);
 856         sock->sk = NULL;
 857
 858         /* Purge queues */
 859
 860         skb_queue_purge(&sk->sk_receive_queue);
 861
 862         sock_put(sk);
 863         return 0;
 864 }
 865
 866 /*
 867  *      Attach a packet hook.
 868  */
 869
 870 static int packet_do_bind(struct sock *sk, struct net_device *dev, int protocol)
 871 {
 872         struct packet_sock *po = pkt_sk(sk);
 873         /*
 874          *      Detach an existing hook if present.
 875          */
 876
 877         lock_sock(sk);
 878
 879         spin_lock(&po->bind_lock);
 880         if (po->running) {
 881                 __sock_put(sk);
 882                 po->running = 0;
 883                 po->num = 0;
 884                 spin_unlock(&po->bind_lock);
 885                 dev_remove_pack(&po->prot_hook);
 886                 spin_lock(&po->bind_lock);
 887         }
 888
 889         po->num = protocol;
 890         po->prot_hook.type = protocol;
 891         po->prot_hook.dev = dev;
 892
 893         po->ifindex = dev ? dev->ifindex : 0;
 894
 895         if (protocol == 0)
 896                 goto out_unlock;
 897
 898         if (dev) {
 899                 if (dev->flags&IFF_UP) {
 900                         dev_add_pack(&po->prot_hook);
 901                         sock_hold(sk);
 902                         po->running = 1;
 903                 } else {
 904                         sk->sk_err = ENETDOWN;
 905                         if (!sock_flag(sk, SOCK_DEAD))
 906                                 sk->sk_error_report(sk);
 907                 }
 908         } else {
 909                 dev_add_pack(&po->prot_hook);
 910                 sock_hold(sk);
 911                 po->running = 1;
 912         }
 913
 914 out_unlock:
 915         spin_unlock(&po->bind_lock);
 916         release_sock(sk);
 917         return 0;
 918 }
 919
 920 /*
 921  *      Bind a packet socket to a device
 922  */
 923
 924 #ifdef CONFIG_SOCK_PACKET
 925
 926 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 927 {
 928         struct sock *sk=sock->sk;
 929         char name[15];
 930         struct net_device *dev;
 931         int err = -ENODEV;
 932
 933         /*
 934          *      Check legality
 935          */
 936
 937         if (addr_len != sizeof(struct sockaddr))
 938                 return -EINVAL;
 939         strlcpy(name,uaddr->sa_data,sizeof(name));
 940
 941         dev = dev_get_by_name(name);
 942         if (dev) {
 943                 err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
 944                 dev_put(dev);
 945         }
 946         return err;
 947 }
 948 #endif
 949
 950 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 951 {
 952         struct sockaddr_ll *sll = (struct sockaddr_ll*)uaddr;
 953         struct sock *sk=sock->sk;
 954         struct net_device *dev = NULL;
 955         int err;
 956
 957
 958         /*
 959          *      Check legality
 960          */
 961
 962         if (addr_len < sizeof(struct sockaddr_ll))
 963                 return -EINVAL;
 964         if (sll->sll_family != AF_PACKET)
 965                 return -EINVAL;
 966
 967         if (sll->sll_ifindex) {
 968                 err = -ENODEV;
 969                 dev = dev_get_by_index(sll->sll_ifindex);
 970                 if (dev == NULL)
 971                         goto out;
 972         }
 973         err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
 974         if (dev)
 975                 dev_put(dev);
 976
 977 out:
 978         return err;
 979 }
 980
 981 static struct proto packet_proto = {
 982         .name     = "PACKET",
 983         .owner    = THIS_MODULE,
 984         .obj_size = sizeof(struct packet_sock),
 985 };
 986
 987 /*
 988  *      Create a packet of type SOCK_PACKET.
 989  */
 990
 991 static int packet_create(struct socket *sock, int protocol)
 992 {
 993         struct sock *sk;
 994         struct packet_sock *po;
 995         int err;
 996
 997         if (!capable(CAP_NET_RAW))
 998                 return -EPERM;
 999         if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW
1000 #ifdef CONFIG_SOCK_PACKET
1001             && sock->type != SOCK_PACKET
1002 #endif
1003             )
1004                 return -ESOCKTNOSUPPORT;
1005
1006         sock->state = SS_UNCONNECTED;
1007
1008         err = -ENOBUFS;
1009         sk = sk_alloc(PF_PACKET, GFP_KERNEL, &packet_proto, 1);
1010         if (sk == NULL)
1011                 goto out;
1012
1013         sock->ops = &packet_ops;
1014 #ifdef CONFIG_SOCK_PACKET
1015         if (sock->type == SOCK_PACKET)
1016                 sock->ops = &packet_ops_spkt;
1017 #endif
1018         sock_init_data(sock, sk);
1019
1020         po = pkt_sk(sk);
1021         sk->sk_family = PF_PACKET;
1022         po->num = protocol;
1023
1024         sk->sk_destruct = packet_sock_destruct;
1025         atomic_inc(&packet_socks_nr);
1026
1027         /*
1028          *      Attach a protocol block
1029          */
1030
1031         spin_lock_init(&po->bind_lock);
1032         po->prot_hook.func = packet_rcv;
1033 #ifdef CONFIG_SOCK_PACKET
1034         if (sock->type == SOCK_PACKET)
1035                 po->prot_hook.func = packet_rcv_spkt;
1036 #endif
1037         po->prot_hook.af_packet_priv = sk;
1038
1039         if (protocol) {
1040                 po->prot_hook.type = protocol;
1041                 dev_add_pack(&po->prot_hook);
1042                 sock_hold(sk);
1043                 po->running = 1;
1044         }
1045
1046         write_lock_bh(&packet_sklist_lock);
1047         sk_add_node(sk, &packet_sklist);
1048         write_unlock_bh(&packet_sklist_lock);
1049         return(0);
1050 out:
1051         return err;
1052 }
1053
1054 /*
1055  *      Pull a packet from our receive queue and hand it to the user.
1056  *      If necessary we block.
1057  */
1058
1059 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
1060                           struct msghdr *msg, size_t len, int flags)
1061 {
1062         struct sock *sk = sock->sk;
1063         struct sk_buff *skb;
1064         int copied, err;
1065         struct sockaddr_ll *sll;
1066
1067         err = -EINVAL;
1068         if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT))
1069                 goto out;
1070
1071 #if 0
1072         /* What error should we return now? EUNATTACH? */
1073         if (pkt_sk(sk)->ifindex < 0)
1074                 return -ENODEV;
1075 #endif
1076
1077         /*
1078          *      Call the generic datagram receiver. This handles all sorts
1079          *      of horrible races and re-entrancy so we can forget about it
1080          *      in the protocol layers.
1081          *
1082          *      Now it will return ENETDOWN, if device have just gone down,
1083          *      but then it will block.
1084          */
1085
1086         skb=skb_recv_datagram(sk,flags,flags&MSG_DONTWAIT,&err);
1087
1088         /*
1089          *      An error occurred so return it. Because skb_recv_datagram()
1090          *      handles the blocking we don't see and worry about blocking
1091          *      retries.
1092          */
1093
1094         if (skb == NULL)
1095                 goto out;
1096
1097         /*
1098          *      If the address length field is there to be filled in, we fill
1099          *      it in now.
1100          */
1101
1102         sll = (struct sockaddr_ll*)skb->cb;
1103         if (sock->type == SOCK_PACKET)
1104                 msg->msg_namelen = sizeof(struct sockaddr_pkt);
1105         else
1106                 msg->msg_namelen = sll->sll_halen + offsetof(struct sockaddr_ll, sll_addr);
1107
1108         /*
1109          *      You lose any data beyond the buffer you gave. If it worries a
1110          *      user program they can ask the device for its MTU anyway.
1111          */
1112
1113         copied = skb->len;
1114         if (copied > len)
1115         {
1116                 copied=len;
1117                 msg->msg_flags|=MSG_TRUNC;
1118         }
1119
1120         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
1121         if (err)
1122                 goto out_free;
1123
1124         sock_recv_timestamp(msg, sk, skb);
1125
1126         if (msg->msg_name)
1127                 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
1128
1129         /*
1130          *      Free or return the buffer as appropriate. Again this
1131          *      hides all the races and re-entrancy issues from us.
1132          */
1133         err = (flags&MSG_TRUNC) ? skb->len : copied;
1134
1135 out_free:
1136         skb_free_datagram(sk, skb);
1137 out:
1138         return err;
1139 }
1140
1141 #ifdef CONFIG_SOCK_PACKET
1142 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
1143                                int *uaddr_len, int peer)
1144 {
1145         struct net_device *dev;
1146         struct sock *sk = sock->sk;
1147
1148         if (peer)
1149                 return -EOPNOTSUPP;
1150
1151         uaddr->sa_family = AF_PACKET;
1152         dev = dev_get_by_index(pkt_sk(sk)->ifindex);
1153         if (dev) {
1154                 strlcpy(uaddr->sa_data, dev->name, 15);
1155                 dev_put(dev);
1156         } else
1157                 memset(uaddr->sa_data, 0, 14);
1158         *uaddr_len = sizeof(*uaddr);
1159
1160         return 0;
1161 }
1162 #endif
1163
1164 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
1165                           int *uaddr_len, int peer)
1166 {
1167         struct net_device *dev;
1168         struct sock *sk = sock->sk;
1169         struct packet_sock *po = pkt_sk(sk);
1170         struct sockaddr_ll *sll = (struct sockaddr_ll*)uaddr;
1171
1172         if (peer)
1173                 return -EOPNOTSUPP;
1174
1175         sll->sll_family = AF_PACKET;
1176         sll->sll_ifindex = po->ifindex;
1177         sll->sll_protocol = po->num;
1178         dev = dev_get_by_index(po->ifindex);
1179         if (dev) {
1180                 sll->sll_hatype = dev->type;
1181                 sll->sll_halen = dev->addr_len;
1182                 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
1183                 dev_put(dev);
1184         } else {
1185                 sll->sll_hatype = 0;    /* Bad: we have no ARPHRD_UNSPEC */
1186                 sll->sll_halen = 0;
1187         }
1188         *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
1189
1190         return 0;
1191 }
1192
1193 #ifdef CONFIG_PACKET_MULTICAST
1194 static void packet_dev_mc(struct net_device *dev, struct packet_mclist *i, int what)
1195 {
1196         switch (i->type) {
1197         case PACKET_MR_MULTICAST:
1198                 if (what > 0)
1199                         dev_mc_add(dev, i->addr, i->alen, 0);
1200                 else
1201                         dev_mc_delete(dev, i->addr, i->alen, 0);
1202                 break;
1203         case PACKET_MR_PROMISC:
1204                 dev_set_promiscuity(dev, what);
1205                 break;
1206         case PACKET_MR_ALLMULTI:
1207                 dev_set_allmulti(dev, what);
1208                 break;
1209         default:;
1210         }
1211 }
1212
1213 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
1214 {
1215         for ( ; i; i=i->next) {
1216                 if (i->ifindex == dev->ifindex)
1217                         packet_dev_mc(dev, i, what);
1218         }
1219 }
1220
1221 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
1222 {
1223         struct packet_sock *po = pkt_sk(sk);
1224         struct packet_mclist *ml, *i;
1225         struct net_device *dev;
1226         int err;
1227
1228         rtnl_lock();
1229
1230         err = -ENODEV;
1231         dev = __dev_get_by_index(mreq->mr_ifindex);
1232         if (!dev)
1233                 goto done;
1234
1235         err = -EINVAL;
1236         if (mreq->mr_alen > dev->addr_len)
1237                 goto done;
1238
1239         err = -ENOBUFS;
1240         i = kmalloc(sizeof(*i), GFP_KERNEL);
1241         if (i == NULL)
1242                 goto done;
1243
1244         err = 0;
1245         for (ml = po->mclist; ml; ml = ml->next) {
1246                 if (ml->ifindex == mreq->mr_ifindex &&
1247                     ml->type == mreq->mr_type &&
1248                     ml->alen == mreq->mr_alen &&
1249                     memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
1250                         ml->count++;
1251                         /* Free the new element ... */
1252                         kfree(i);
1253                         goto done;
1254                 }
1255         }
1256
1257         i->type = mreq->mr_type;
1258         i->ifindex = mreq->mr_ifindex;
1259         i->alen = mreq->mr_alen;
1260         memcpy(i->addr, mreq->mr_address, i->alen);
1261         i->count = 1;
1262         i->next = po->mclist;
1263         po->mclist = i;
1264         packet_dev_mc(dev, i, +1);
1265
1266 done:
1267         rtnl_unlock();
1268         return err;
1269 }
1270
1271 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
1272 {
1273         struct packet_mclist *ml, **mlp;
1274
1275         rtnl_lock();
1276
1277         for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
1278                 if (ml->ifindex == mreq->mr_ifindex &&
1279                     ml->type == mreq->mr_type &&
1280                     ml->alen == mreq->mr_alen &&
1281                     memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
1282                         if (--ml->count == 0) {
1283                                 struct net_device *dev;
1284                                 *mlp = ml->next;
1285                                 dev = dev_get_by_index(ml->ifindex);
1286                                 if (dev) {
1287                                         packet_dev_mc(dev, ml, -1);
1288                                         dev_put(dev);
1289                                 }
1290                                 kfree(ml);
1291                         }
1292                         rtnl_unlock();
1293                         return 0;
1294                 }
1295         }
1296         rtnl_unlock();
1297         return -EADDRNOTAVAIL;
1298 }
1299
1300 static void packet_flush_mclist(struct sock *sk)
1301 {
1302         struct packet_sock *po = pkt_sk(sk);
1303         struct packet_mclist *ml;
1304
1305         if (!po->mclist)
1306                 return;
1307
1308         rtnl_lock();
1309         while ((ml = po->mclist) != NULL) {
1310                 struct net_device *dev;
1311
1312                 po->mclist = ml->next;
1313                 if ((dev = dev_get_by_index(ml->ifindex)) != NULL) {
1314                         packet_dev_mc(dev, ml, -1);
1315                         dev_put(dev);
1316                 }
1317                 kfree(ml);
1318         }
1319         rtnl_unlock();
1320 }
1321 #endif
1322
1323 static int
1324 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, int optlen)
1325 {
1326         struct sock *sk = sock->sk;
1327         int ret;
1328
1329         if (level != SOL_PACKET)
1330                 return -ENOPROTOOPT;
1331
1332         switch(optname) {
1333 #ifdef CONFIG_PACKET_MULTICAST
1334         case PACKET_ADD_MEMBERSHIP:
1335         case PACKET_DROP_MEMBERSHIP:
1336         {
1337                 struct packet_mreq_max mreq;
1338                 int len = optlen;
1339                 memset(&mreq, 0, sizeof(mreq));
1340                 if (len < sizeof(struct packet_mreq))
1341                         return -EINVAL;
1342                 if (len > sizeof(mreq))
1343                         len = sizeof(mreq);
1344                 if (copy_from_user(&mreq,optval,len))
1345                         return -EFAULT;
1346                 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
1347                         return -EINVAL;
1348                 if (optname == PACKET_ADD_MEMBERSHIP)
1349                         ret = packet_mc_add(sk, &mreq);
1350                 else
1351                         ret = packet_mc_drop(sk, &mreq);
1352                 return ret;
1353         }
1354 #endif
1355 #ifdef CONFIG_PACKET_MMAP
1356         case PACKET_RX_RING:
1357         {
1358                 struct tpacket_req req;
1359
1360                 if (optlen<sizeof(req))
1361                         return -EINVAL;
1362                 if (copy_from_user(&req,optval,sizeof(req)))
1363                         return -EFAULT;
1364                 return packet_set_ring(sk, &req, 0);
1365         }
1366         case PACKET_COPY_THRESH:
1367         {
1368                 int val;
1369
1370                 if (optlen!=sizeof(val))
1371                         return -EINVAL;
1372                 if (copy_from_user(&val,optval,sizeof(val)))
1373                         return -EFAULT;
1374
1375                 pkt_sk(sk)->copy_thresh = val;
1376                 return 0;
1377         }
1378 #endif
1379         default:
1380                 return -ENOPROTOOPT;
1381         }
1382 }
1383
1384 static int packet_getsockopt(struct socket *sock, int level, int optname,
1385                              char __user *optval, int __user *optlen)
1386 {
1387         int len;
1388         struct sock *sk = sock->sk;
1389         struct packet_sock *po = pkt_sk(sk);
1390
1391         if (level != SOL_PACKET)
1392                 return -ENOPROTOOPT;
1393
1394         if (get_user(len, optlen))
1395                 return -EFAULT;
1396
1397         if (len < 0)
1398                 return -EINVAL;
1399
1400         switch(optname) {
1401         case PACKET_STATISTICS:
1402         {
1403                 struct tpacket_stats st;
1404
1405                 if (len > sizeof(struct tpacket_stats))
1406                         len = sizeof(struct tpacket_stats);
1407                 spin_lock_bh(&sk->sk_receive_queue.lock);
1408                 st = po->stats;
1409                 memset(&po->stats, 0, sizeof(st));
1410                 spin_unlock_bh(&sk->sk_receive_queue.lock);
1411                 st.tp_packets += st.tp_drops;
1412
1413                 if (copy_to_user(optval, &st, len))
1414                         return -EFAULT;
1415                 break;
1416         }
1417         default:
1418                 return -ENOPROTOOPT;
1419         }
1420
1421         if (put_user(len, optlen))
1422                 return -EFAULT;
1423         return 0;
1424 }
1425
1426
1427 static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data)
1428 {
1429         struct sock *sk;
1430         struct hlist_node *node;
1431         struct net_device *dev = (struct net_device*)data;
1432
1433         read_lock(&packet_sklist_lock);
1434         sk_for_each(sk, node, &packet_sklist) {
1435                 struct packet_sock *po = pkt_sk(sk);
1436
1437                 switch (msg) {
1438                 case NETDEV_UNREGISTER:
1439 #ifdef CONFIG_PACKET_MULTICAST
1440                         if (po->mclist)
1441                                 packet_dev_mclist(dev, po->mclist, -1);
1442                         // fallthrough
1443 #endif
1444                 case NETDEV_DOWN:
1445                         if (dev->ifindex == po->ifindex) {
1446                                 spin_lock(&po->bind_lock);
1447                                 if (po->running) {
1448                                         __dev_remove_pack(&po->prot_hook);
1449                                         __sock_put(sk);
1450                                         po->running = 0;
1451                                         sk->sk_err = ENETDOWN;
1452                                         if (!sock_flag(sk, SOCK_DEAD))
1453                                                 sk->sk_error_report(sk);
1454                                 }
1455                                 if (msg == NETDEV_UNREGISTER) {
1456                                         po->ifindex = -1;
1457                                         po->prot_hook.dev = NULL;
1458                                 }
1459                                 spin_unlock(&po->bind_lock);
1460                         }
1461                         break;
1462                 case NETDEV_UP:
1463                         spin_lock(&po->bind_lock);
1464                         if (dev->ifindex == po->ifindex && po->num &&
1465                             !po->running) {
1466                                 dev_add_pack(&po->prot_hook);
1467                                 sock_hold(sk);
1468                                 po->running = 1;
1469                         }
1470                         spin_unlock(&po->bind_lock);
1471                         break;
1472                 }
1473         }
1474         read_unlock(&packet_sklist_lock);
1475         return NOTIFY_DONE;
1476 }
1477
1478
1479 static int packet_ioctl(struct socket *sock, unsigned int cmd,
1480                         unsigned long arg)
1481 {
1482         struct sock *sk = sock->sk;
1483
1484         switch(cmd) {
1485                 case SIOCOUTQ:
1486                 {
1487                         int amount = atomic_read(&sk->sk_wmem_alloc);
1488                         return put_user(amount, (int __user *)arg);
1489                 }
1490                 case SIOCINQ:
1491                 {
1492                         struct sk_buff *skb;
1493                         int amount = 0;
1494
1495                         spin_lock_bh(&sk->sk_receive_queue.lock);
1496                         skb = skb_peek(&sk->sk_receive_queue);
1497                         if (skb)
1498                                 amount = skb->len;
1499                         spin_unlock_bh(&sk->sk_receive_queue.lock);
1500                         return put_user(amount, (int __user *)arg);
1501                 }
1502                 case SIOCGSTAMP:
1503                         return sock_get_timestamp(sk, (struct timeval __user *)arg);
1504
1505 #ifdef CONFIG_INET
1506                 case SIOCADDRT:
1507                 case SIOCDELRT:
1508                 case SIOCDARP:
1509                 case SIOCGARP:
1510                 case SIOCSARP:
1511                 case SIOCGIFADDR:
1512                 case SIOCSIFADDR:
1513                 case SIOCGIFBRDADDR:
1514                 case SIOCSIFBRDADDR:
1515                 case SIOCGIFNETMASK:
1516                 case SIOCSIFNETMASK:
1517                 case SIOCGIFDSTADDR:
1518                 case SIOCSIFDSTADDR:
1519                 case SIOCSIFFLAGS:
1520                         return inet_dgram_ops.ioctl(sock, cmd, arg);
1521 #endif
1522
1523                 default:
1524                         return -ENOIOCTLCMD;
1525         }
1526         return 0;
1527 }
1528
1529 #ifndef CONFIG_PACKET_MMAP
1530 #define packet_mmap sock_no_mmap
1531 #define packet_poll datagram_poll
1532 #else
1533
1534 static unsigned int packet_poll(struct file * file, struct socket *sock,
1535                                 poll_table *wait)
1536 {
1537         struct sock *sk = sock->sk;
1538         struct packet_sock *po = pkt_sk(sk);
1539         unsigned int mask = datagram_poll(file, sock, wait);
1540
1541         spin_lock_bh(&sk->sk_receive_queue.lock);
1542         if (po->pg_vec) {
1543                 unsigned last = po->head ? po->head-1 : po->frame_max;
1544                 struct tpacket_hdr *h;
1545
1546                 h = (struct tpacket_hdr *)packet_lookup_frame(po, last);
1547
1548                 if (h->tp_status)
1549                         mask |= POLLIN | POLLRDNORM;
1550         }
1551         spin_unlock_bh(&sk->sk_receive_queue.lock);
1552         return mask;
1553 }
1554
1555
1556 /* Dirty? Well, I still did not learn better way to account
1557  * for user mmaps.
1558  */
1559
1560 static void packet_mm_open(struct vm_area_struct *vma)
1561 {
1562         struct file *file = vma->vm_file;
1563         struct socket * sock = file->private_data;
1564         struct sock *sk = sock->sk;
1565
1566         if (sk)
1567                 atomic_inc(&pkt_sk(sk)->mapped);
1568 }
1569
1570 static void packet_mm_close(struct vm_area_struct *vma)
1571 {
1572         struct file *file = vma->vm_file;
1573         struct socket * sock = file->private_data;
1574         struct sock *sk = sock->sk;
1575
1576         if (sk)
1577                 atomic_dec(&pkt_sk(sk)->mapped);
1578 }
1579
1580 static struct vm_operations_struct packet_mmap_ops = {
1581         .open = packet_mm_open,
1582         .close =packet_mm_close,
1583 };
1584
1585 static inline struct page *pg_vec_endpage(char *one_pg_vec, unsigned int order)
1586 {
1587         return virt_to_page(one_pg_vec + (PAGE_SIZE << order) - 1);
1588 }
1589
1590 static void free_pg_vec(char **pg_vec, unsigned int order, unsigned int len)
1591 {
1592         int i;
1593
1594         for (i = 0; i < len; i++) {
1595                 if (likely(pg_vec[i]))
1596                         free_pages((unsigned long) pg_vec[i], order);
1597         }
1598         kfree(pg_vec);
1599 }
1600
1601 static inline char *alloc_one_pg_vec_page(unsigned long order)
1602 {
1603         return (char *) __get_free_pages(GFP_KERNEL | __GFP_COMP | __GFP_ZERO,
1604                                          order);
1605 }
1606
1607 static char **alloc_pg_vec(struct tpacket_req *req, int order)
1608 {
1609         unsigned int block_nr = req->tp_block_nr;
1610         char **pg_vec;
1611         int i;
1612
1613         pg_vec = kzalloc(block_nr * sizeof(char *), GFP_KERNEL);
1614         if (unlikely(!pg_vec))
1615                 goto out;
1616
1617         for (i = 0; i < block_nr; i++) {
1618                 pg_vec[i] = alloc_one_pg_vec_page(order);
1619                 if (unlikely(!pg_vec[i]))
1620                         goto out_free_pgvec;
1621         }
1622
1623 out:
1624         return pg_vec;
1625
1626 out_free_pgvec:
1627         free_pg_vec(pg_vec, order, block_nr);
1628         pg_vec = NULL;
1629         goto out;
1630 }
1631
1632 static int packet_set_ring(struct sock *sk, struct tpacket_req *req, int closing)
1633 {
1634         char **pg_vec = NULL;
1635         struct packet_sock *po = pkt_sk(sk);
1636         int was_running, num, order = 0;
1637         int err = 0;
1638
1639         if (req->tp_block_nr) {
1640                 int i, l;
1641
1642                 /* Sanity tests and some calculations */
1643
1644                 if (unlikely(po->pg_vec))
1645                         return -EBUSY;
1646
1647                 if (unlikely((int)req->tp_block_size <= 0))
1648                         return -EINVAL;
1649                 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
1650                         return -EINVAL;
1651                 if (unlikely(req->tp_frame_size < TPACKET_HDRLEN))
1652                         return -EINVAL;
1653                 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
1654                         return -EINVAL;
1655
1656                 po->frames_per_block = req->tp_block_size/req->tp_frame_size;
1657                 if (unlikely(po->frames_per_block <= 0))
1658                         return -EINVAL;
1659                 if (unlikely((po->frames_per_block * req->tp_block_nr) !=
1660                              req->tp_frame_nr))
1661                         return -EINVAL;
1662
1663                 err = -ENOMEM;
1664                 order = get_order(req->tp_block_size);
1665                 pg_vec = alloc_pg_vec(req, order);
1666                 if (unlikely(!pg_vec))
1667                         goto out;
1668
1669                 l = 0;
1670                 for (i = 0; i < req->tp_block_nr; i++) {
1671                         char *ptr = pg_vec[i];
1672                         struct tpacket_hdr *header;
1673                         int k;
1674
1675                         for (k = 0; k < po->frames_per_block; k++) {
1676                                 header = (struct tpacket_hdr *) ptr;
1677                                 header->tp_status = TP_STATUS_KERNEL;
1678                                 ptr += req->tp_frame_size;
1679                         }
1680                 }
1681                 /* Done */
1682         } else {
1683                 if (unlikely(req->tp_frame_nr))
1684                         return -EINVAL;
1685         }
1686
1687         lock_sock(sk);
1688
1689         /* Detach socket from network */
1690         spin_lock(&po->bind_lock);
1691         was_running = po->running;
1692         num = po->num;
1693         if (was_running) {
1694                 __dev_remove_pack(&po->prot_hook);
1695                 po->num = 0;
1696                 po->running = 0;
1697                 __sock_put(sk);
1698         }
1699         spin_unlock(&po->bind_lock);
1700
1701         synchronize_net();
1702
1703         err = -EBUSY;
1704         if (closing || atomic_read(&po->mapped) == 0) {
1705                 err = 0;
1706 #define XC(a, b) ({ __typeof__ ((a)) __t; __t = (a); (a) = (b); __t; })
1707
1708                 spin_lock_bh(&sk->sk_receive_queue.lock);
1709                 pg_vec = XC(po->pg_vec, pg_vec);
1710                 po->frame_max = (req->tp_frame_nr - 1);
1711                 po->head = 0;
1712                 po->frame_size = req->tp_frame_size;
1713                 spin_unlock_bh(&sk->sk_receive_queue.lock);
1714
1715                 order = XC(po->pg_vec_order, order);
1716                 req->tp_block_nr = XC(po->pg_vec_len, req->tp_block_nr);
1717
1718                 po->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
1719                 po->prot_hook.func = po->pg_vec ? tpacket_rcv : packet_rcv;
1720                 skb_queue_purge(&sk->sk_receive_queue);
1721 #undef XC
1722                 if (atomic_read(&po->mapped))
1723                         printk(KERN_DEBUG "packet_mmap: vma is busy: %d\n", atomic_read(&po->mapped));
1724         }
1725
1726         spin_lock(&po->bind_lock);
1727         if (was_running && !po->running) {
1728                 sock_hold(sk);
1729                 po->running = 1;
1730                 po->num = num;
1731                 dev_add_pack(&po->prot_hook);
1732         }
1733         spin_unlock(&po->bind_lock);
1734
1735         release_sock(sk);
1736
1737         if (pg_vec)
1738                 free_pg_vec(pg_vec, order, req->tp_block_nr);
1739 out:
1740         return err;
1741 }
1742
1743 static int packet_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
1744 {
1745         struct sock *sk = sock->sk;
1746         struct packet_sock *po = pkt_sk(sk);
1747         unsigned long size;
1748         unsigned long start;
1749         int err = -EINVAL;
1750         int i;
1751
1752         if (vma->vm_pgoff)
1753                 return -EINVAL;
1754
1755         size = vma->vm_end - vma->vm_start;
1756
1757         lock_sock(sk);
1758         if (po->pg_vec == NULL)
1759                 goto out;
1760         if (size != po->pg_vec_len*po->pg_vec_pages*PAGE_SIZE)
1761                 goto out;
1762
1763         start = vma->vm_start;
1764         for (i = 0; i < po->pg_vec_len; i++) {
1765                 struct page *page = virt_to_page(po->pg_vec[i]);
1766                 int pg_num;
1767
1768                 for (pg_num = 0; pg_num < po->pg_vec_pages; pg_num++, page++) {
1769                         err = vm_insert_page(vma, start, page);
1770                         if (unlikely(err))
1771                                 goto out;
1772                         start += PAGE_SIZE;
1773                 }
1774         }
1775         atomic_inc(&po->mapped);
1776         vma->vm_ops = &packet_mmap_ops;
1777         err = 0;
1778
1779 out:
1780         release_sock(sk);
1781         return err;
1782 }
1783 #endif
1784
1785
1786 #ifdef CONFIG_SOCK_PACKET
1787 static const struct proto_ops packet_ops_spkt = {
1788         .family =       PF_PACKET,
1789         .owner =        THIS_MODULE,
1790         .release =      packet_release,
1791         .bind =         packet_bind_spkt,
1792         .connect =      sock_no_connect,
1793         .socketpair =   sock_no_socketpair,
1794         .accept =       sock_no_accept,
1795         .getname =      packet_getname_spkt,
1796         .poll =         datagram_poll,
1797         .ioctl =        packet_ioctl,
1798         .listen =       sock_no_listen,
1799         .shutdown =     sock_no_shutdown,
1800         .setsockopt =   sock_no_setsockopt,
1801         .getsockopt =   sock_no_getsockopt,
1802         .sendmsg =      packet_sendmsg_spkt,
1803         .recvmsg =      packet_recvmsg,
1804         .mmap =         sock_no_mmap,
1805         .sendpage =     sock_no_sendpage,
1806 };
1807 #endif
1808
1809 static const struct proto_ops packet_ops = {
1810         .family =       PF_PACKET,
1811         .owner =        THIS_MODULE,
1812         .release =      packet_release,
1813         .bind =         packet_bind,
1814         .connect =      sock_no_connect,
1815         .socketpair =   sock_no_socketpair,
1816         .accept =       sock_no_accept,
1817         .getname =      packet_getname,
1818         .poll =         packet_poll,
1819         .ioctl =        packet_ioctl,
1820         .listen =       sock_no_listen,
1821         .shutdown =     sock_no_shutdown,
1822         .setsockopt =   packet_setsockopt,
1823         .getsockopt =   packet_getsockopt,
1824         .sendmsg =      packet_sendmsg,
1825         .recvmsg =      packet_recvmsg,
1826         .mmap =         packet_mmap,
1827         .sendpage =     sock_no_sendpage,
1828 };
1829
1830 static struct net_proto_family packet_family_ops = {
1831         .family =       PF_PACKET,
1832         .create =       packet_create,
1833         .owner  =       THIS_MODULE,
1834 };
1835
1836 static struct notifier_block packet_netdev_notifier = {
1837         .notifier_call =packet_notifier,
1838 };
1839
1840 #ifdef CONFIG_PROC_FS
1841 static inline struct sock *packet_seq_idx(loff_t off)
1842 {
1843         struct sock *s;
1844         struct hlist_node *node;
1845
1846         sk_for_each(s, node, &packet_sklist) {
1847                 if (!off--)
1848                         return s;
1849         }
1850         return NULL;
1851 }
1852
1853 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
1854 {
1855         read_lock(&packet_sklist_lock);
1856         return *pos ? packet_seq_idx(*pos - 1) : SEQ_START_TOKEN;
1857 }
1858
1859 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1860 {
1861         ++*pos;
1862         return  (v == SEQ_START_TOKEN)
1863                 ? sk_head(&packet_sklist)
1864                 : sk_next((struct sock*)v) ;
1865 }
1866
1867 static void packet_seq_stop(struct seq_file *seq, void *v)
1868 {
1869         read_unlock(&packet_sklist_lock);
1870 }
1871
1872 static int packet_seq_show(struct seq_file *seq, void *v)
1873 {
1874         if (v == SEQ_START_TOKEN)
1875                 seq_puts(seq, "sk       RefCnt Type Proto  Iface R Rmem   User   Inode\n");
1876         else {
1877                 struct sock *s = v;
1878                 const struct packet_sock *po = pkt_sk(s);
1879
1880                 seq_printf(seq,
1881                            "%p %-6d %-4d %04x   %-5d %1d %-6u %-6u %-6lu\n",
1882                            s,
1883                            atomic_read(&s->sk_refcnt),
1884                            s->sk_type,
1885                            ntohs(po->num),
1886                            po->ifindex,
1887                            po->running,
1888                            atomic_read(&s->sk_rmem_alloc),
1889                            sock_i_uid(s),
1890                            sock_i_ino(s) );
1891         }
1892
1893         return 0;
1894 }
1895
1896 static struct seq_operations packet_seq_ops = {
1897         .start  = packet_seq_start,
1898         .next   = packet_seq_next,
1899         .stop   = packet_seq_stop,
1900         .show   = packet_seq_show,
1901 };
1902
1903 static int packet_seq_open(struct inode *inode, struct file *file)
1904 {
1905         return seq_open(file, &packet_seq_ops);
1906 }
1907
1908 static struct file_operations packet_seq_fops = {
1909         .owner          = THIS_MODULE,
1910         .open           = packet_seq_open,
1911         .read           = seq_read,
1912         .llseek         = seq_lseek,
1913         .release        = seq_release,
1914 };
1915
1916 #endif
1917
1918 static void __exit packet_exit(void)
1919 {
1920         proc_net_remove("packet");
1921         unregister_netdevice_notifier(&packet_netdev_notifier);
1922         sock_unregister(PF_PACKET);
1923         proto_unregister(&packet_proto);
1924 }
1925
1926 static int __init packet_init(void)
1927 {
1928         int rc = proto_register(&packet_proto, 0);
1929
1930         if (rc != 0)
1931                 goto out;
1932
1933         sock_register(&packet_family_ops);
1934         register_netdevice_notifier(&packet_netdev_notifier);
1935         proc_net_fops_create("packet", 0, &packet_seq_fops);
1936 out:
1937         return rc;
1938 }
1939
1940 module_init(packet_init);
1941 module_exit(packet_exit);
1942 MODULE_LICENSE("GPL");
1943 MODULE_ALIAS_NETPROTO(PF_PACKET);