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  * Authors:     Ross Biro
   9  *              Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  10  *              Alan Cox, <gw4pts@gw4pts.ampr.org>
  11  *
  12  * Fixes:
  13  *              Alan Cox        :       verify_area() now used correctly
  14  *              Alan Cox        :       new skbuff lists, look ma no backlogs!
  15  *              Alan Cox        :       tidied skbuff lists.
  16  *              Alan Cox        :       Now uses generic datagram routines I
  17  *                                      added. Also fixed the peek/read crash
  18  *                                      from all old Linux datagram code.
  19  *              Alan Cox        :       Uses the improved datagram code.
  20  *              Alan Cox        :       Added NULL's for socket options.
  21  *              Alan Cox        :       Re-commented the code.
  22  *              Alan Cox        :       Use new kernel side addressing
  23  *              Rob Janssen     :       Correct MTU usage.
  24  *              Dave Platt      :       Counter leaks caused by incorrect
  25  *                                      interrupt locking and some slightly
  26  *                                      dubious gcc output. Can you read
  27  *                                      compiler: it said _VOLATILE_
  28  *      Richard Kooijman        :       Timestamp fixes.
  29  *              Alan Cox        :       New buffers. Use sk->mac.raw.
  30  *              Alan Cox        :       sendmsg/recvmsg support.
  31  *              Alan Cox        :       Protocol setting support
  32  *      Alexey Kuznetsov        :       Untied from IPv4 stack.
  33  *      Cyrus Durgin            :       Fixed kerneld for kmod.
  34  *      Michal Ostrowski        :       Module initialization cleanup.
  35  *         Ulises Alonso        :       Frame number limit removal and
  36  *                                      packet_set_ring memory leak.
  37  *              Eric Biederman  :       Allow for > 8 byte hardware addresses.
  38  *                                      The convention is that longer addresses
  39  *                                      will simply extend the hardware address
  40  *                                      byte arrays at the end of sockaddr_ll
  41  *                                      and packet_mreq.
  42  *              Johann Baudy    :       Added TX RING.
  43  *
  44  *              This program is free software; you can redistribute it and/or
  45  *              modify it under the terms of the GNU General Public License
  46  *              as published by the Free Software Foundation; either version
  47  *              2 of the License, or (at your option) any later version.
  48  *
  49  */
  50
  51 #include <linux/types.h>
  52 #include <linux/mm.h>
  53 #include <linux/capability.h>
  54 #include <linux/fcntl.h>
  55 #include <linux/socket.h>
  56 #include <linux/in.h>
  57 #include <linux/inet.h>
  58 #include <linux/netdevice.h>
  59 #include <linux/if_packet.h>
  60 #include <linux/wireless.h>
  61 #include <linux/kernel.h>
  62 #include <linux/kmod.h>
  63 #include <linux/slab.h>
  64 #include <linux/vmalloc.h>
  65 #include <net/net_namespace.h>
  66 #include <net/ip.h>
  67 #include <net/protocol.h>
  68 #include <linux/skbuff.h>
  69 #include <net/sock.h>
  70 #include <linux/errno.h>
  71 #include <linux/timer.h>
  72 #include <asm/system.h>
  73 #include <asm/uaccess.h>
  74 #include <asm/ioctls.h>
  75 #include <asm/page.h>
  76 #include <asm/cacheflush.h>
  77 #include <asm/io.h>
  78 #include <linux/proc_fs.h>
  79 #include <linux/seq_file.h>
  80 #include <linux/poll.h>
  81 #include <linux/module.h>
  82 #include <linux/init.h>
  83 #include <linux/mutex.h>
  84 #include <linux/if_vlan.h>
  85 #include <linux/virtio_net.h>
  86 #include <linux/errqueue.h>
  87 #include <linux/net_tstamp.h>
  88
  89 #ifdef CONFIG_INET
  90 #include <net/inet_common.h>
  91 #endif
  92
  93 /*
  94    Assumptions:
  95    - if device has no dev->hard_header routine, it adds and removes ll header
  96      inside itself. In this case ll header is invisible outside of device,
  97      but higher levels still should reserve dev->hard_header_len.
  98      Some devices are enough clever to reallocate skb, when header
  99      will not fit to reserved space (tunnel), another ones are silly
 100      (PPP).
 101    - packet socket receives packets with pulled ll header,
 102      so that SOCK_RAW should push it back.
 103
 104 On receive:
 105 -----------
 106
 107 Incoming, dev->hard_header!=NULL
 108    mac_header -> ll header
 109    data       -> data
 110
 111 Outgoing, dev->hard_header!=NULL
 112    mac_header -> ll header
 113    data       -> ll header
 114
 115 Incoming, dev->hard_header==NULL
 116    mac_header -> UNKNOWN position. It is very likely, that it points to ll
 117                  header.  PPP makes it, that is wrong, because introduce
 118                  assymetry between rx and tx paths.
 119    data       -> data
 120
 121 Outgoing, dev->hard_header==NULL
 122    mac_header -> data. ll header is still not built!
 123    data       -> data
 124
 125 Resume
 126   If dev->hard_header==NULL we are unlikely to restore sensible ll header.
 127
 128
 129 On transmit:
 130 ------------
 131
 132 dev->hard_header != NULL
 133    mac_header -> ll header
 134    data       -> ll header
 135
 136 dev->hard_header == NULL (ll header is added by device, we cannot control it)
 137    mac_header -> data
 138    data       -> data
 139
 140    We should set nh.raw on output to correct posistion,
 141    packet classifier depends on it.
 142  */
 143
 144 /* Private packet socket structures. */
 145
 146 struct packet_mclist {
 147         struct packet_mclist    *next;
 148         int                     ifindex;
 149         int                     count;
 150         unsigned short          type;
 151         unsigned short          alen;
 152         unsigned char           addr[MAX_ADDR_LEN];
 153 };
 154 /* identical to struct packet_mreq except it has
 155  * a longer address field.
 156  */
 157 struct packet_mreq_max {
 158         int             mr_ifindex;
 159         unsigned short  mr_type;
 160         unsigned short  mr_alen;
 161         unsigned char   mr_address[MAX_ADDR_LEN];
 162 };
 163
 164 static int packet_set_ring(struct sock *sk, struct tpacket_req *req,
 165                 int closing, int tx_ring);
 166
 167 #define PGV_FROM_VMALLOC 1
 168 struct pgv {
 169         char *buffer;
 170 };
 171
 172 struct packet_ring_buffer {
 173         struct pgv              *pg_vec;
 174         unsigned int            head;
 175         unsigned int            frames_per_block;
 176         unsigned int            frame_size;
 177         unsigned int            frame_max;
 178
 179         unsigned int            pg_vec_order;
 180         unsigned int            pg_vec_pages;
 181         unsigned int            pg_vec_len;
 182
 183         atomic_t                pending;
 184 };
 185
 186 struct packet_sock;
 187 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg);
 188
 189 static void packet_flush_mclist(struct sock *sk);
 190
 191 struct packet_sock {
 192         /* struct sock has to be the first member of packet_sock */
 193         struct sock             sk;
 194         struct tpacket_stats    stats;
 195         struct packet_ring_buffer       rx_ring;
 196         struct packet_ring_buffer       tx_ring;
 197         int                     copy_thresh;
 198         spinlock_t              bind_lock;
 199         struct mutex            pg_vec_lock;
 200         unsigned int            running:1,      /* prot_hook is attached*/
 201                                 auxdata:1,
 202                                 origdev:1,
 203                                 has_vnet_hdr:1;
 204         int                     ifindex;        /* bound device         */
 205         __be16                  num;
 206         struct packet_mclist    *mclist;
 207         atomic_t                mapped;
 208         enum tpacket_versions   tp_version;
 209         unsigned int            tp_hdrlen;
 210         unsigned int            tp_reserve;
 211         unsigned int            tp_loss:1;
 212         unsigned int            tp_tstamp;
 213         struct packet_type      prot_hook ____cacheline_aligned_in_smp;
 214 };
 215
 216 struct packet_skb_cb {
 217         unsigned int origlen;
 218         union {
 219                 struct sockaddr_pkt pkt;
 220                 struct sockaddr_ll ll;
 221         } sa;
 222 };
 223
 224 #define PACKET_SKB_CB(__skb)    ((struct packet_skb_cb *)((__skb)->cb))
 225
 226 static inline __pure struct page *pgv_to_page(void *addr)
 227 {
 228         if (is_vmalloc_addr(addr))
 229                 return vmalloc_to_page(addr);
 230         return virt_to_page(addr);
 231 }
 232
 233 static void __packet_set_status(struct packet_sock *po, void *frame, int status)
 234 {
 235         union {
 236                 struct tpacket_hdr *h1;
 237                 struct tpacket2_hdr *h2;
 238                 void *raw;
 239         } h;
 240
 241         h.raw = frame;
 242         switch (po->tp_version) {
 243         case TPACKET_V1:
 244                 h.h1->tp_status = status;
 245                 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
 246                 break;
 247         case TPACKET_V2:
 248                 h.h2->tp_status = status;
 249                 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
 250                 break;
 251         default:
 252                 pr_err("TPACKET version not supported\n");
 253                 BUG();
 254         }
 255
 256         smp_wmb();
 257 }
 258
 259 static int __packet_get_status(struct packet_sock *po, void *frame)
 260 {
 261         union {
 262                 struct tpacket_hdr *h1;
 263                 struct tpacket2_hdr *h2;
 264                 void *raw;
 265         } h;
 266
 267         smp_rmb();
 268
 269         h.raw = frame;
 270         switch (po->tp_version) {
 271         case TPACKET_V1:
 272                 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
 273                 return h.h1->tp_status;
 274         case TPACKET_V2:
 275                 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
 276                 return h.h2->tp_status;
 277         default:
 278                 pr_err("TPACKET version not supported\n");
 279                 BUG();
 280                 return 0;
 281         }
 282 }
 283
 284 static void *packet_lookup_frame(struct packet_sock *po,
 285                 struct packet_ring_buffer *rb,
 286                 unsigned int position,
 287                 int status)
 288 {
 289         unsigned int pg_vec_pos, frame_offset;
 290         union {
 291                 struct tpacket_hdr *h1;
 292                 struct tpacket2_hdr *h2;
 293                 void *raw;
 294         } h;
 295
 296         pg_vec_pos = position / rb->frames_per_block;
 297         frame_offset = position % rb->frames_per_block;
 298
 299         h.raw = rb->pg_vec[pg_vec_pos].buffer +
 300                 (frame_offset * rb->frame_size);
 301
 302         if (status != __packet_get_status(po, h.raw))
 303                 return NULL;
 304
 305         return h.raw;
 306 }
 307
 308 static inline void *packet_current_frame(struct packet_sock *po,
 309                 struct packet_ring_buffer *rb,
 310                 int status)
 311 {
 312         return packet_lookup_frame(po, rb, rb->head, status);
 313 }
 314
 315 static inline void *packet_previous_frame(struct packet_sock *po,
 316                 struct packet_ring_buffer *rb,
 317                 int status)
 318 {
 319         unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
 320         return packet_lookup_frame(po, rb, previous, status);
 321 }
 322
 323 static inline void packet_increment_head(struct packet_ring_buffer *buff)
 324 {
 325         buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
 326 }
 327
 328 static inline struct packet_sock *pkt_sk(struct sock *sk)
 329 {
 330         return (struct packet_sock *)sk;
 331 }
 332
 333 static void packet_sock_destruct(struct sock *sk)
 334 {
 335         skb_queue_purge(&sk->sk_error_queue);
 336
 337         WARN_ON(atomic_read(&sk->sk_rmem_alloc));
 338         WARN_ON(atomic_read(&sk->sk_wmem_alloc));
 339
 340         if (!sock_flag(sk, SOCK_DEAD)) {
 341                 pr_err("Attempt to release alive packet socket: %p\n", sk);
 342                 return;
 343         }
 344
 345         sk_refcnt_debug_dec(sk);
 346 }
 347
 348
 349 static const struct proto_ops packet_ops;
 350
 351 static const struct proto_ops packet_ops_spkt;
 352
 353 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
 354                            struct packet_type *pt, struct net_device *orig_dev)
 355 {
 356         struct sock *sk;
 357         struct sockaddr_pkt *spkt;
 358
 359         /*
 360          *      When we registered the protocol we saved the socket in the data
 361          *      field for just this event.
 362          */
 363
 364         sk = pt->af_packet_priv;
 365
 366         /*
 367          *      Yank back the headers [hope the device set this
 368          *      right or kerboom...]
 369          *
 370          *      Incoming packets have ll header pulled,
 371          *      push it back.
 372          *
 373          *      For outgoing ones skb->data == skb_mac_header(skb)
 374          *      so that this procedure is noop.
 375          */
 376
 377         if (skb->pkt_type == PACKET_LOOPBACK)
 378                 goto out;
 379
 380         if (!net_eq(dev_net(dev), sock_net(sk)))
 381                 goto out;
 382
 383         skb = skb_share_check(skb, GFP_ATOMIC);
 384         if (skb == NULL)
 385                 goto oom;
 386
 387         /* drop any routing info */
 388         skb_dst_drop(skb);
 389
 390         /* drop conntrack reference */
 391         nf_reset(skb);
 392
 393         spkt = &PACKET_SKB_CB(skb)->sa.pkt;
 394
 395         skb_push(skb, skb->data - skb_mac_header(skb));
 396
 397         /*
 398          *      The SOCK_PACKET socket receives _all_ frames.
 399          */
 400
 401         spkt->spkt_family = dev->type;
 402         strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
 403         spkt->spkt_protocol = skb->protocol;
 404
 405         /*
 406          *      Charge the memory to the socket. This is done specifically
 407          *      to prevent sockets using all the memory up.
 408          */
 409
 410         if (sock_queue_rcv_skb(sk, skb) == 0)
 411                 return 0;
 412
 413 out:
 414         kfree_skb(skb);
 415 oom:
 416         return 0;
 417 }
 418
 419
 420 /*
 421  *      Output a raw packet to a device layer. This bypasses all the other
 422  *      protocol layers and you must therefore supply it with a complete frame
 423  */
 424
 425 static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
 426                                struct msghdr *msg, size_t len)
 427 {
 428         struct sock *sk = sock->sk;
 429         struct sockaddr_pkt *saddr = (struct sockaddr_pkt *)msg->msg_name;
 430         struct sk_buff *skb = NULL;
 431         struct net_device *dev;
 432         __be16 proto = 0;
 433         int err;
 434
 435         /*
 436          *      Get and verify the address.
 437          */
 438
 439         if (saddr) {
 440                 if (msg->msg_namelen < sizeof(struct sockaddr))
 441                         return -EINVAL;
 442                 if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
 443                         proto = saddr->spkt_protocol;
 444         } else
 445                 return -ENOTCONN;       /* SOCK_PACKET must be sent giving an address */
 446
 447         /*
 448          *      Find the device first to size check it
 449          */
 450
 451         saddr->spkt_device[13] = 0;
 452 retry:
 453         rcu_read_lock();
 454         dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
 455         err = -ENODEV;
 456         if (dev == NULL)
 457                 goto out_unlock;
 458
 459         err = -ENETDOWN;
 460         if (!(dev->flags & IFF_UP))
 461                 goto out_unlock;
 462
 463         /*
 464          * You may not queue a frame bigger than the mtu. This is the lowest level
 465          * raw protocol and you must do your own fragmentation at this level.
 466          */
 467
 468         err = -EMSGSIZE;
 469         if (len > dev->mtu + dev->hard_header_len)
 470                 goto out_unlock;
 471
 472         if (!skb) {
 473                 size_t reserved = LL_RESERVED_SPACE(dev);
 474                 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
 475
 476                 rcu_read_unlock();
 477                 skb = sock_wmalloc(sk, len + reserved, 0, GFP_KERNEL);
 478                 if (skb == NULL)
 479                         return -ENOBUFS;
 480                 /* FIXME: Save some space for broken drivers that write a hard
 481                  * header at transmission time by themselves. PPP is the notable
 482                  * one here. This should really be fixed at the driver level.
 483                  */
 484                 skb_reserve(skb, reserved);
 485                 skb_reset_network_header(skb);
 486
 487                 /* Try to align data part correctly */
 488                 if (hhlen) {
 489                         skb->data -= hhlen;
 490                         skb->tail -= hhlen;
 491                         if (len < hhlen)
 492                                 skb_reset_network_header(skb);
 493                 }
 494                 err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
 495                 if (err)
 496                         goto out_free;
 497                 goto retry;
 498         }
 499
 500
 501         skb->protocol = proto;
 502         skb->dev = dev;
 503         skb->priority = sk->sk_priority;
 504         skb->mark = sk->sk_mark;
 505         err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
 506         if (err < 0)
 507                 goto out_unlock;
 508
 509         dev_queue_xmit(skb);
 510         rcu_read_unlock();
 511         return len;
 512
 513 out_unlock:
 514         rcu_read_unlock();
 515 out_free:
 516         kfree_skb(skb);
 517         return err;
 518 }
 519
 520 static inline unsigned int run_filter(const struct sk_buff *skb,
 521                                       const struct sock *sk,
 522                                       unsigned int res)
 523 {
 524         struct sk_filter *filter;
 525
 526         rcu_read_lock_bh();
 527         filter = rcu_dereference_bh(sk->sk_filter);
 528         if (filter != NULL)
 529                 res = sk_run_filter(skb, filter->insns);
 530         rcu_read_unlock_bh();
 531
 532         return res;
 533 }
 534
 535 /*
 536  * This function makes lazy skb cloning in hope that most of packets
 537  * are discarded by BPF.
 538  *
 539  * Note tricky part: we DO mangle shared skb! skb->data, skb->len
 540  * and skb->cb are mangled. It works because (and until) packets
 541  * falling here are owned by current CPU. Output packets are cloned
 542  * by dev_queue_xmit_nit(), input packets are processed by net_bh
 543  * sequencially, so that if we return skb to original state on exit,
 544  * we will not harm anyone.
 545  */
 546
 547 static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
 548                       struct packet_type *pt, struct net_device *orig_dev)
 549 {
 550         struct sock *sk;
 551         struct sockaddr_ll *sll;
 552         struct packet_sock *po;
 553         u8 *skb_head = skb->data;
 554         int skb_len = skb->len;
 555         unsigned int snaplen, res;
 556
 557         if (skb->pkt_type == PACKET_LOOPBACK)
 558                 goto drop;
 559
 560         sk = pt->af_packet_priv;
 561         po = pkt_sk(sk);
 562
 563         if (!net_eq(dev_net(dev), sock_net(sk)))
 564                 goto drop;
 565
 566         skb->dev = dev;
 567
 568         if (dev->header_ops) {
 569                 /* The device has an explicit notion of ll header,
 570                  * exported to higher levels.
 571                  *
 572                  * Otherwise, the device hides details of its frame
 573                  * structure, so that corresponding packet head is
 574                  * never delivered to user.
 575                  */
 576                 if (sk->sk_type != SOCK_DGRAM)
 577                         skb_push(skb, skb->data - skb_mac_header(skb));
 578                 else if (skb->pkt_type == PACKET_OUTGOING) {
 579                         /* Special case: outgoing packets have ll header at head */
 580                         skb_pull(skb, skb_network_offset(skb));
 581                 }
 582         }
 583
 584         snaplen = skb->len;
 585
 586         res = run_filter(skb, sk, snaplen);
 587         if (!res)
 588                 goto drop_n_restore;
 589         if (snaplen > res)
 590                 snaplen = res;
 591
 592         if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
 593             (unsigned)sk->sk_rcvbuf)
 594                 goto drop_n_acct;
 595
 596         if (skb_shared(skb)) {
 597                 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
 598                 if (nskb == NULL)
 599                         goto drop_n_acct;
 600
 601                 if (skb_head != skb->data) {
 602                         skb->data = skb_head;
 603                         skb->len = skb_len;
 604                 }
 605                 kfree_skb(skb);
 606                 skb = nskb;
 607         }
 608
 609         BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 >
 610                      sizeof(skb->cb));
 611
 612         sll = &PACKET_SKB_CB(skb)->sa.ll;
 613         sll->sll_family = AF_PACKET;
 614         sll->sll_hatype = dev->type;
 615         sll->sll_protocol = skb->protocol;
 616         sll->sll_pkttype = skb->pkt_type;
 617         if (unlikely(po->origdev))
 618                 sll->sll_ifindex = orig_dev->ifindex;
 619         else
 620                 sll->sll_ifindex = dev->ifindex;
 621
 622         sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
 623
 624         PACKET_SKB_CB(skb)->origlen = skb->len;
 625
 626         if (pskb_trim(skb, snaplen))
 627                 goto drop_n_acct;
 628
 629         skb_set_owner_r(skb, sk);
 630         skb->dev = NULL;
 631         skb_dst_drop(skb);
 632
 633         /* drop conntrack reference */
 634         nf_reset(skb);
 635
 636         spin_lock(&sk->sk_receive_queue.lock);
 637         po->stats.tp_packets++;
 638         skb->dropcount = atomic_read(&sk->sk_drops);
 639         __skb_queue_tail(&sk->sk_receive_queue, skb);
 640         spin_unlock(&sk->sk_receive_queue.lock);
 641         sk->sk_data_ready(sk, skb->len);
 642         return 0;
 643
 644 drop_n_acct:
 645         po->stats.tp_drops = atomic_inc_return(&sk->sk_drops);
 646
 647 drop_n_restore:
 648         if (skb_head != skb->data && skb_shared(skb)) {
 649                 skb->data = skb_head;
 650                 skb->len = skb_len;
 651         }
 652 drop:
 653         consume_skb(skb);
 654         return 0;
 655 }
 656
 657 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
 658                        struct packet_type *pt, struct net_device *orig_dev)
 659 {
 660         struct sock *sk;
 661         struct packet_sock *po;
 662         struct sockaddr_ll *sll;
 663         union {
 664                 struct tpacket_hdr *h1;
 665                 struct tpacket2_hdr *h2;
 666                 void *raw;
 667         } h;
 668         u8 *skb_head = skb->data;
 669         int skb_len = skb->len;
 670         unsigned int snaplen, res;
 671         unsigned long status = TP_STATUS_LOSING|TP_STATUS_USER;
 672         unsigned short macoff, netoff, hdrlen;
 673         struct sk_buff *copy_skb = NULL;
 674         struct timeval tv;
 675         struct timespec ts;
 676         struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
 677
 678         if (skb->pkt_type == PACKET_LOOPBACK)
 679                 goto drop;
 680
 681         sk = pt->af_packet_priv;
 682         po = pkt_sk(sk);
 683
 684         if (!net_eq(dev_net(dev), sock_net(sk)))
 685                 goto drop;
 686
 687         if (dev->header_ops) {
 688                 if (sk->sk_type != SOCK_DGRAM)
 689                         skb_push(skb, skb->data - skb_mac_header(skb));
 690                 else if (skb->pkt_type == PACKET_OUTGOING) {
 691                         /* Special case: outgoing packets have ll header at head */
 692                         skb_pull(skb, skb_network_offset(skb));
 693                 }
 694         }
 695
 696         if (skb->ip_summed == CHECKSUM_PARTIAL)
 697                 status |= TP_STATUS_CSUMNOTREADY;
 698
 699         snaplen = skb->len;
 700
 701         res = run_filter(skb, sk, snaplen);
 702         if (!res)
 703                 goto drop_n_restore;
 704         if (snaplen > res)
 705                 snaplen = res;
 706
 707         if (sk->sk_type == SOCK_DGRAM) {
 708                 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
 709                                   po->tp_reserve;
 710         } else {
 711                 unsigned maclen = skb_network_offset(skb);
 712                 netoff = TPACKET_ALIGN(po->tp_hdrlen +
 713                                        (maclen < 16 ? 16 : maclen)) +
 714                         po->tp_reserve;
 715                 macoff = netoff - maclen;
 716         }
 717
 718         if (macoff + snaplen > po->rx_ring.frame_size) {
 719                 if (po->copy_thresh &&
 720                     atomic_read(&sk->sk_rmem_alloc) + skb->truesize <
 721                     (unsigned)sk->sk_rcvbuf) {
 722                         if (skb_shared(skb)) {
 723                                 copy_skb = skb_clone(skb, GFP_ATOMIC);
 724                         } else {
 725                                 copy_skb = skb_get(skb);
 726                                 skb_head = skb->data;
 727                         }
 728                         if (copy_skb)
 729                                 skb_set_owner_r(copy_skb, sk);
 730                 }
 731                 snaplen = po->rx_ring.frame_size - macoff;
 732                 if ((int)snaplen < 0)
 733                         snaplen = 0;
 734         }
 735
 736         spin_lock(&sk->sk_receive_queue.lock);
 737         h.raw = packet_current_frame(po, &po->rx_ring, TP_STATUS_KERNEL);
 738         if (!h.raw)
 739                 goto ring_is_full;
 740         packet_increment_head(&po->rx_ring);
 741         po->stats.tp_packets++;
 742         if (copy_skb) {
 743                 status |= TP_STATUS_COPY;
 744                 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
 745         }
 746         if (!po->stats.tp_drops)
 747                 status &= ~TP_STATUS_LOSING;
 748         spin_unlock(&sk->sk_receive_queue.lock);
 749
 750         skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
 751
 752         switch (po->tp_version) {
 753         case TPACKET_V1:
 754                 h.h1->tp_len = skb->len;
 755                 h.h1->tp_snaplen = snaplen;
 756                 h.h1->tp_mac = macoff;
 757                 h.h1->tp_net = netoff;
 758                 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
 759                                 && shhwtstamps->syststamp.tv64)
 760                         tv = ktime_to_timeval(shhwtstamps->syststamp);
 761                 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
 762                                 && shhwtstamps->hwtstamp.tv64)
 763                         tv = ktime_to_timeval(shhwtstamps->hwtstamp);
 764                 else if (skb->tstamp.tv64)
 765                         tv = ktime_to_timeval(skb->tstamp);
 766                 else
 767                         do_gettimeofday(&tv);
 768                 h.h1->tp_sec = tv.tv_sec;
 769                 h.h1->tp_usec = tv.tv_usec;
 770                 hdrlen = sizeof(*h.h1);
 771                 break;
 772         case TPACKET_V2:
 773                 h.h2->tp_len = skb->len;
 774                 h.h2->tp_snaplen = snaplen;
 775                 h.h2->tp_mac = macoff;
 776                 h.h2->tp_net = netoff;
 777                 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE)
 778                                 && shhwtstamps->syststamp.tv64)
 779                         ts = ktime_to_timespec(shhwtstamps->syststamp);
 780                 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE)
 781                                 && shhwtstamps->hwtstamp.tv64)
 782                         ts = ktime_to_timespec(shhwtstamps->hwtstamp);
 783                 else if (skb->tstamp.tv64)
 784                         ts = ktime_to_timespec(skb->tstamp);
 785                 else
 786                         getnstimeofday(&ts);
 787                 h.h2->tp_sec = ts.tv_sec;
 788                 h.h2->tp_nsec = ts.tv_nsec;
 789                 h.h2->tp_vlan_tci = vlan_tx_tag_get(skb);
 790                 hdrlen = sizeof(*h.h2);
 791                 break;
 792         default:
 793                 BUG();
 794         }
 795
 796         sll = h.raw + TPACKET_ALIGN(hdrlen);
 797         sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
 798         sll->sll_family = AF_PACKET;
 799         sll->sll_hatype = dev->type;
 800         sll->sll_protocol = skb->protocol;
 801         sll->sll_pkttype = skb->pkt_type;
 802         if (unlikely(po->origdev))
 803                 sll->sll_ifindex = orig_dev->ifindex;
 804         else
 805                 sll->sll_ifindex = dev->ifindex;
 806
 807         __packet_set_status(po, h.raw, status);
 808         smp_mb();
 809 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
 810         {
 811                 u8 *start, *end;
 812
 813                 end = (u8 *)PAGE_ALIGN((unsigned long)h.raw + macoff + snaplen);
 814                 for (start = h.raw; start < end; start += PAGE_SIZE)
 815                         flush_dcache_page(pgv_to_page(start));
 816         }
 817 #endif
 818
 819         sk->sk_data_ready(sk, 0);
 820
 821 drop_n_restore:
 822         if (skb_head != skb->data && skb_shared(skb)) {
 823                 skb->data = skb_head;
 824                 skb->len = skb_len;
 825         }
 826 drop:
 827         kfree_skb(skb);
 828         return 0;
 829
 830 ring_is_full:
 831         po->stats.tp_drops++;
 832         spin_unlock(&sk->sk_receive_queue.lock);
 833
 834         sk->sk_data_ready(sk, 0);
 835         kfree_skb(copy_skb);
 836         goto drop_n_restore;
 837 }
 838
 839 static void tpacket_destruct_skb(struct sk_buff *skb)
 840 {
 841         struct packet_sock *po = pkt_sk(skb->sk);
 842         void *ph;
 843
 844         BUG_ON(skb == NULL);
 845
 846         if (likely(po->tx_ring.pg_vec)) {
 847                 ph = skb_shinfo(skb)->destructor_arg;
 848                 BUG_ON(__packet_get_status(po, ph) != TP_STATUS_SENDING);
 849                 BUG_ON(atomic_read(&po->tx_ring.pending) == 0);
 850                 atomic_dec(&po->tx_ring.pending);
 851                 __packet_set_status(po, ph, TP_STATUS_AVAILABLE);
 852         }
 853
 854         sock_wfree(skb);
 855 }
 856
 857 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
 858                 void *frame, struct net_device *dev, int size_max,
 859                 __be16 proto, unsigned char *addr)
 860 {
 861         union {
 862                 struct tpacket_hdr *h1;
 863                 struct tpacket2_hdr *h2;
 864                 void *raw;
 865         } ph;
 866         int to_write, offset, len, tp_len, nr_frags, len_max;
 867         struct socket *sock = po->sk.sk_socket;
 868         struct page *page;
 869         void *data;
 870         int err;
 871
 872         ph.raw = frame;
 873
 874         skb->protocol = proto;
 875         skb->dev = dev;
 876         skb->priority = po->sk.sk_priority;
 877         skb->mark = po->sk.sk_mark;
 878         skb_shinfo(skb)->destructor_arg = ph.raw;
 879
 880         switch (po->tp_version) {
 881         case TPACKET_V2:
 882                 tp_len = ph.h2->tp_len;
 883                 break;
 884         default:
 885                 tp_len = ph.h1->tp_len;
 886                 break;
 887         }
 888         if (unlikely(tp_len > size_max)) {
 889                 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
 890                 return -EMSGSIZE;
 891         }
 892
 893         skb_reserve(skb, LL_RESERVED_SPACE(dev));
 894         skb_reset_network_header(skb);
 895
 896         data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll);
 897         to_write = tp_len;
 898
 899         if (sock->type == SOCK_DGRAM) {
 900                 err = dev_hard_header(skb, dev, ntohs(proto), addr,
 901                                 NULL, tp_len);
 902                 if (unlikely(err < 0))
 903                         return -EINVAL;
 904         } else if (dev->hard_header_len) {
 905                 /* net device doesn't like empty head */
 906                 if (unlikely(tp_len <= dev->hard_header_len)) {
 907                         pr_err("packet size is too short (%d < %d)\n",
 908                                tp_len, dev->hard_header_len);
 909                         return -EINVAL;
 910                 }
 911
 912                 skb_push(skb, dev->hard_header_len);
 913                 err = skb_store_bits(skb, 0, data,
 914                                 dev->hard_header_len);
 915                 if (unlikely(err))
 916                         return err;
 917
 918                 data += dev->hard_header_len;
 919                 to_write -= dev->hard_header_len;
 920         }
 921
 922         err = -EFAULT;
 923         offset = offset_in_page(data);
 924         len_max = PAGE_SIZE - offset;
 925         len = ((to_write > len_max) ? len_max : to_write);
 926
 927         skb->data_len = to_write;
 928         skb->len += to_write;
 929         skb->truesize += to_write;
 930         atomic_add(to_write, &po->sk.sk_wmem_alloc);
 931
 932         while (likely(to_write)) {
 933                 nr_frags = skb_shinfo(skb)->nr_frags;
 934
 935                 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
 936                         pr_err("Packet exceed the number of skb frags(%lu)\n",
 937                                MAX_SKB_FRAGS);
 938                         return -EFAULT;
 939                 }
 940
 941                 page = pgv_to_page(data);
 942                 data += len;
 943                 flush_dcache_page(page);
 944                 get_page(page);
 945                 skb_fill_page_desc(skb, nr_frags, page, offset, len);
 946                 to_write -= len;
 947                 offset = 0;
 948                 len_max = PAGE_SIZE;
 949                 len = ((to_write > len_max) ? len_max : to_write);
 950         }
 951
 952         return tp_len;
 953 }
 954
 955 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
 956 {
 957         struct socket *sock;
 958         struct sk_buff *skb;
 959         struct net_device *dev;
 960         __be16 proto;
 961         int ifindex, err, reserve = 0;
 962         void *ph;
 963         struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
 964         int tp_len, size_max;
 965         unsigned char *addr;
 966         int len_sum = 0;
 967         int status = 0;
 968
 969         sock = po->sk.sk_socket;
 970
 971         mutex_lock(&po->pg_vec_lock);
 972
 973         err = -EBUSY;
 974         if (saddr == NULL) {
 975                 ifindex = po->ifindex;
 976                 proto   = po->num;
 977                 addr    = NULL;
 978         } else {
 979                 err = -EINVAL;
 980                 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
 981                         goto out;
 982                 if (msg->msg_namelen < (saddr->sll_halen
 983                                         + offsetof(struct sockaddr_ll,
 984                                                 sll_addr)))
 985                         goto out;
 986                 ifindex = saddr->sll_ifindex;
 987                 proto   = saddr->sll_protocol;
 988                 addr    = saddr->sll_addr;
 989         }
 990
 991         dev = dev_get_by_index(sock_net(&po->sk), ifindex);
 992         err = -ENXIO;
 993         if (unlikely(dev == NULL))
 994                 goto out;
 995
 996         reserve = dev->hard_header_len;
 997
 998         err = -ENETDOWN;
 999         if (unlikely(!(dev->flags & IFF_UP)))
1000                 goto out_put;
1001
1002         size_max = po->tx_ring.frame_size
1003                 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
1004
1005         if (size_max > dev->mtu + reserve)
1006                 size_max = dev->mtu + reserve;
1007
1008         do {
1009                 ph = packet_current_frame(po, &po->tx_ring,
1010                                 TP_STATUS_SEND_REQUEST);
1011
1012                 if (unlikely(ph == NULL)) {
1013                         schedule();
1014                         continue;
1015                 }
1016
1017                 status = TP_STATUS_SEND_REQUEST;
1018                 skb = sock_alloc_send_skb(&po->sk,
1019                                 LL_ALLOCATED_SPACE(dev)
1020                                 + sizeof(struct sockaddr_ll),
1021                                 0, &err);
1022
1023                 if (unlikely(skb == NULL))
1024                         goto out_status;
1025
1026                 tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
1027                                 addr);
1028
1029                 if (unlikely(tp_len < 0)) {
1030                         if (po->tp_loss) {
1031                                 __packet_set_status(po, ph,
1032                                                 TP_STATUS_AVAILABLE);
1033                                 packet_increment_head(&po->tx_ring);
1034                                 kfree_skb(skb);
1035                                 continue;
1036                         } else {
1037                                 status = TP_STATUS_WRONG_FORMAT;
1038                                 err = tp_len;
1039                                 goto out_status;
1040                         }
1041                 }
1042
1043                 skb->destructor = tpacket_destruct_skb;
1044                 __packet_set_status(po, ph, TP_STATUS_SENDING);
1045                 atomic_inc(&po->tx_ring.pending);
1046
1047                 status = TP_STATUS_SEND_REQUEST;
1048                 err = dev_queue_xmit(skb);
1049                 if (unlikely(err > 0)) {
1050                         err = net_xmit_errno(err);
1051                         if (err && __packet_get_status(po, ph) ==
1052                                    TP_STATUS_AVAILABLE) {
1053                                 /* skb was destructed already */
1054                                 skb = NULL;
1055                                 goto out_status;
1056                         }
1057                         /*
1058                          * skb was dropped but not destructed yet;
1059                          * let's treat it like congestion or err < 0
1060                          */
1061                         err = 0;
1062                 }
1063                 packet_increment_head(&po->tx_ring);
1064                 len_sum += tp_len;
1065         } while (likely((ph != NULL) ||
1066                         ((!(msg->msg_flags & MSG_DONTWAIT)) &&
1067                          (atomic_read(&po->tx_ring.pending))))
1068                 );
1069
1070         err = len_sum;
1071         goto out_put;
1072
1073 out_status:
1074         __packet_set_status(po, ph, status);
1075         kfree_skb(skb);
1076 out_put:
1077         dev_put(dev);
1078 out:
1079         mutex_unlock(&po->pg_vec_lock);
1080         return err;
1081 }
1082
1083 static inline struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
1084                                                size_t reserve, size_t len,
1085                                                size_t linear, int noblock,
1086                                                int *err)
1087 {
1088         struct sk_buff *skb;
1089
1090         /* Under a page?  Don't bother with paged skb. */
1091         if (prepad + len < PAGE_SIZE || !linear)
1092                 linear = len;
1093
1094         skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
1095                                    err);
1096         if (!skb)
1097                 return NULL;
1098
1099         skb_reserve(skb, reserve);
1100         skb_put(skb, linear);
1101         skb->data_len = len - linear;
1102         skb->len += len - linear;
1103
1104         return skb;
1105 }
1106
1107 static int packet_snd(struct socket *sock,
1108                           struct msghdr *msg, size_t len)
1109 {
1110         struct sock *sk = sock->sk;
1111         struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name;
1112         struct sk_buff *skb;
1113         struct net_device *dev;
1114         __be16 proto;
1115         unsigned char *addr;
1116         int ifindex, err, reserve = 0;
1117         struct virtio_net_hdr vnet_hdr = { 0 };
1118         int offset = 0;
1119         int vnet_hdr_len;
1120         struct packet_sock *po = pkt_sk(sk);
1121         unsigned short gso_type = 0;
1122
1123         /*
1124          *      Get and verify the address.
1125          */
1126
1127         if (saddr == NULL) {
1128                 ifindex = po->ifindex;
1129                 proto   = po->num;
1130                 addr    = NULL;
1131         } else {
1132                 err = -EINVAL;
1133                 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
1134                         goto out;
1135                 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
1136                         goto out;
1137                 ifindex = saddr->sll_ifindex;
1138                 proto   = saddr->sll_protocol;
1139                 addr    = saddr->sll_addr;
1140         }
1141
1142
1143         dev = dev_get_by_index(sock_net(sk), ifindex);
1144         err = -ENXIO;
1145         if (dev == NULL)
1146                 goto out_unlock;
1147         if (sock->type == SOCK_RAW)
1148                 reserve = dev->hard_header_len;
1149
1150         err = -ENETDOWN;
1151         if (!(dev->flags & IFF_UP))
1152                 goto out_unlock;
1153
1154         if (po->has_vnet_hdr) {
1155                 vnet_hdr_len = sizeof(vnet_hdr);
1156
1157                 err = -EINVAL;
1158                 if (len < vnet_hdr_len)
1159                         goto out_unlock;
1160
1161                 len -= vnet_hdr_len;
1162
1163                 err = memcpy_fromiovec((void *)&vnet_hdr, msg->msg_iov,
1164                                        vnet_hdr_len);
1165                 if (err < 0)
1166                         goto out_unlock;
1167
1168                 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
1169                     (vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 >
1170                       vnet_hdr.hdr_len))
1171                         vnet_hdr.hdr_len = vnet_hdr.csum_start +
1172                                                  vnet_hdr.csum_offset + 2;
1173
1174                 err = -EINVAL;
1175                 if (vnet_hdr.hdr_len > len)
1176                         goto out_unlock;
1177
1178                 if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
1179                         switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
1180                         case VIRTIO_NET_HDR_GSO_TCPV4:
1181                                 gso_type = SKB_GSO_TCPV4;
1182                                 break;
1183                         case VIRTIO_NET_HDR_GSO_TCPV6:
1184                                 gso_type = SKB_GSO_TCPV6;
1185                                 break;
1186                         case VIRTIO_NET_HDR_GSO_UDP:
1187                                 gso_type = SKB_GSO_UDP;
1188                                 break;
1189                         default:
1190                                 goto out_unlock;
1191                         }
1192
1193                         if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
1194                                 gso_type |= SKB_GSO_TCP_ECN;
1195
1196                         if (vnet_hdr.gso_size == 0)
1197                                 goto out_unlock;
1198
1199                 }
1200         }
1201
1202         err = -EMSGSIZE;
1203         if (!gso_type && (len > dev->mtu+reserve))
1204                 goto out_unlock;
1205
1206         err = -ENOBUFS;
1207         skb = packet_alloc_skb(sk, LL_ALLOCATED_SPACE(dev),
1208                                LL_RESERVED_SPACE(dev), len, vnet_hdr.hdr_len,
1209                                msg->msg_flags & MSG_DONTWAIT, &err);
1210         if (skb == NULL)
1211                 goto out_unlock;
1212
1213         skb_set_network_header(skb, reserve);
1214
1215         err = -EINVAL;
1216         if (sock->type == SOCK_DGRAM &&
1217             (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0)
1218                 goto out_free;
1219
1220         /* Returns -EFAULT on error */
1221         err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len);
1222         if (err)
1223                 goto out_free;
1224         err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
1225         if (err < 0)
1226                 goto out_free;
1227
1228         skb->protocol = proto;
1229         skb->dev = dev;
1230         skb->priority = sk->sk_priority;
1231         skb->mark = sk->sk_mark;
1232
1233         if (po->has_vnet_hdr) {
1234                 if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
1235                         if (!skb_partial_csum_set(skb, vnet_hdr.csum_start,
1236                                                   vnet_hdr.csum_offset)) {
1237                                 err = -EINVAL;
1238                                 goto out_free;
1239                         }
1240                 }
1241
1242                 skb_shinfo(skb)->gso_size = vnet_hdr.gso_size;
1243                 skb_shinfo(skb)->gso_type = gso_type;
1244
1245                 /* Header must be checked, and gso_segs computed. */
1246                 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
1247                 skb_shinfo(skb)->gso_segs = 0;
1248
1249                 len += vnet_hdr_len;
1250         }
1251
1252         /*
1253          *      Now send it
1254          */
1255
1256         err = dev_queue_xmit(skb);
1257         if (err > 0 && (err = net_xmit_errno(err)) != 0)
1258                 goto out_unlock;
1259
1260         dev_put(dev);
1261
1262         return len;
1263
1264 out_free:
1265         kfree_skb(skb);
1266 out_unlock:
1267         if (dev)
1268                 dev_put(dev);
1269 out:
1270         return err;
1271 }
1272
1273 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
1274                 struct msghdr *msg, size_t len)
1275 {
1276         struct sock *sk = sock->sk;
1277         struct packet_sock *po = pkt_sk(sk);
1278         if (po->tx_ring.pg_vec)
1279                 return tpacket_snd(po, msg);
1280         else
1281                 return packet_snd(sock, msg, len);
1282 }
1283
1284 /*
1285  *      Close a PACKET socket. This is fairly simple. We immediately go
1286  *      to 'closed' state and remove our protocol entry in the device list.
1287  */
1288
1289 static int packet_release(struct socket *sock)
1290 {
1291         struct sock *sk = sock->sk;
1292         struct packet_sock *po;
1293         struct net *net;
1294         struct tpacket_req req;
1295
1296         if (!sk)
1297                 return 0;
1298
1299         net = sock_net(sk);
1300         po = pkt_sk(sk);
1301
1302         spin_lock_bh(&net->packet.sklist_lock);
1303         sk_del_node_init_rcu(sk);
1304         sock_prot_inuse_add(net, sk->sk_prot, -1);
1305         spin_unlock_bh(&net->packet.sklist_lock);
1306
1307         spin_lock(&po->bind_lock);
1308         if (po->running) {
1309                 /*
1310                  * Remove from protocol table
1311                  */
1312                 po->running = 0;
1313                 po->num = 0;
1314                 __dev_remove_pack(&po->prot_hook);
1315                 __sock_put(sk);
1316         }
1317         spin_unlock(&po->bind_lock);
1318
1319         packet_flush_mclist(sk);
1320
1321         memset(&req, 0, sizeof(req));
1322
1323         if (po->rx_ring.pg_vec)
1324                 packet_set_ring(sk, &req, 1, 0);
1325
1326         if (po->tx_ring.pg_vec)
1327                 packet_set_ring(sk, &req, 1, 1);
1328
1329         synchronize_net();
1330         /*
1331          *      Now the socket is dead. No more input will appear.
1332          */
1333         sock_orphan(sk);
1334         sock->sk = NULL;
1335
1336         /* Purge queues */
1337
1338         skb_queue_purge(&sk->sk_receive_queue);
1339         sk_refcnt_debug_release(sk);
1340
1341         sock_put(sk);
1342         return 0;
1343 }
1344
1345 /*
1346  *      Attach a packet hook.
1347  */
1348
1349 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol)
1350 {
1351         struct packet_sock *po = pkt_sk(sk);
1352         /*
1353          *      Detach an existing hook if present.
1354          */
1355
1356         lock_sock(sk);
1357
1358         spin_lock(&po->bind_lock);
1359         if (po->running) {
1360                 __sock_put(sk);
1361                 po->running = 0;
1362                 po->num = 0;
1363                 spin_unlock(&po->bind_lock);
1364                 dev_remove_pack(&po->prot_hook);
1365                 spin_lock(&po->bind_lock);
1366         }
1367
1368         po->num = protocol;
1369         po->prot_hook.type = protocol;
1370         po->prot_hook.dev = dev;
1371
1372         po->ifindex = dev ? dev->ifindex : 0;
1373
1374         if (protocol == 0)
1375                 goto out_unlock;
1376
1377         if (!dev || (dev->flags & IFF_UP)) {
1378                 dev_add_pack(&po->prot_hook);
1379                 sock_hold(sk);
1380                 po->running = 1;
1381         } else {
1382                 sk->sk_err = ENETDOWN;
1383                 if (!sock_flag(sk, SOCK_DEAD))
1384                         sk->sk_error_report(sk);
1385         }
1386
1387 out_unlock:
1388         spin_unlock(&po->bind_lock);
1389         release_sock(sk);
1390         return 0;
1391 }
1392
1393 /*
1394  *      Bind a packet socket to a device
1395  */
1396
1397 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
1398                             int addr_len)
1399 {
1400         struct sock *sk = sock->sk;
1401         char name[15];
1402         struct net_device *dev;
1403         int err = -ENODEV;
1404
1405         /*
1406          *      Check legality
1407          */
1408
1409         if (addr_len != sizeof(struct sockaddr))
1410                 return -EINVAL;
1411         strlcpy(name, uaddr->sa_data, sizeof(name));
1412
1413         dev = dev_get_by_name(sock_net(sk), name);
1414         if (dev) {
1415                 err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
1416                 dev_put(dev);
1417         }
1418         return err;
1419 }
1420
1421 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
1422 {
1423         struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
1424         struct sock *sk = sock->sk;
1425         struct net_device *dev = NULL;
1426         int err;
1427
1428
1429         /*
1430          *      Check legality
1431          */
1432
1433         if (addr_len < sizeof(struct sockaddr_ll))
1434                 return -EINVAL;
1435         if (sll->sll_family != AF_PACKET)
1436                 return -EINVAL;
1437
1438         if (sll->sll_ifindex) {
1439                 err = -ENODEV;
1440                 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
1441                 if (dev == NULL)
1442                         goto out;
1443         }
1444         err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
1445         if (dev)
1446                 dev_put(dev);
1447
1448 out:
1449         return err;
1450 }
1451
1452 static struct proto packet_proto = {
1453         .name     = "PACKET",
1454         .owner    = THIS_MODULE,
1455         .obj_size = sizeof(struct packet_sock),
1456 };
1457
1458 /*
1459  *      Create a packet of type SOCK_PACKET.
1460  */
1461
1462 static int packet_create(struct net *net, struct socket *sock, int protocol,
1463                          int kern)
1464 {
1465         struct sock *sk;
1466         struct packet_sock *po;
1467         __be16 proto = (__force __be16)protocol; /* weird, but documented */
1468         int err;
1469
1470         if (!capable(CAP_NET_RAW))
1471                 return -EPERM;
1472         if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
1473             sock->type != SOCK_PACKET)
1474                 return -ESOCKTNOSUPPORT;
1475
1476         sock->state = SS_UNCONNECTED;
1477
1478         err = -ENOBUFS;
1479         sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
1480         if (sk == NULL)
1481                 goto out;
1482
1483         sock->ops = &packet_ops;
1484         if (sock->type == SOCK_PACKET)
1485                 sock->ops = &packet_ops_spkt;
1486
1487         sock_init_data(sock, sk);
1488
1489         po = pkt_sk(sk);
1490         sk->sk_family = PF_PACKET;
1491         po->num = proto;
1492
1493         sk->sk_destruct = packet_sock_destruct;
1494         sk_refcnt_debug_inc(sk);
1495
1496         /*
1497          *      Attach a protocol block
1498          */
1499
1500         spin_lock_init(&po->bind_lock);
1501         mutex_init(&po->pg_vec_lock);
1502         po->prot_hook.func = packet_rcv;
1503
1504         if (sock->type == SOCK_PACKET)
1505                 po->prot_hook.func = packet_rcv_spkt;
1506
1507         po->prot_hook.af_packet_priv = sk;
1508
1509         if (proto) {
1510                 po->prot_hook.type = proto;
1511                 dev_add_pack(&po->prot_hook);
1512                 sock_hold(sk);
1513                 po->running = 1;
1514         }
1515
1516         spin_lock_bh(&net->packet.sklist_lock);
1517         sk_add_node_rcu(sk, &net->packet.sklist);
1518         sock_prot_inuse_add(net, &packet_proto, 1);
1519         spin_unlock_bh(&net->packet.sklist_lock);
1520
1521         return 0;
1522 out:
1523         return err;
1524 }
1525
1526 static int packet_recv_error(struct sock *sk, struct msghdr *msg, int len)
1527 {
1528         struct sock_exterr_skb *serr;
1529         struct sk_buff *skb, *skb2;
1530         int copied, err;
1531
1532         err = -EAGAIN;
1533         skb = skb_dequeue(&sk->sk_error_queue);
1534         if (skb == NULL)
1535                 goto out;
1536
1537         copied = skb->len;
1538         if (copied > len) {
1539                 msg->msg_flags |= MSG_TRUNC;
1540                 copied = len;
1541         }
1542         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
1543         if (err)
1544                 goto out_free_skb;
1545
1546         sock_recv_timestamp(msg, sk, skb);
1547
1548         serr = SKB_EXT_ERR(skb);
1549         put_cmsg(msg, SOL_PACKET, PACKET_TX_TIMESTAMP,
1550                  sizeof(serr->ee), &serr->ee);
1551
1552         msg->msg_flags |= MSG_ERRQUEUE;
1553         err = copied;
1554
1555         /* Reset and regenerate socket error */
1556         spin_lock_bh(&sk->sk_error_queue.lock);
1557         sk->sk_err = 0;
1558         if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
1559                 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
1560                 spin_unlock_bh(&sk->sk_error_queue.lock);
1561                 sk->sk_error_report(sk);
1562         } else
1563                 spin_unlock_bh(&sk->sk_error_queue.lock);
1564
1565 out_free_skb:
1566         kfree_skb(skb);
1567 out:
1568         return err;
1569 }
1570
1571 /*
1572  *      Pull a packet from our receive queue and hand it to the user.
1573  *      If necessary we block.
1574  */
1575
1576 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
1577                           struct msghdr *msg, size_t len, int flags)
1578 {
1579         struct sock *sk = sock->sk;
1580         struct sk_buff *skb;
1581         int copied, err;
1582         struct sockaddr_ll *sll;
1583         int vnet_hdr_len = 0;
1584
1585         err = -EINVAL;
1586         if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
1587                 goto out;
1588
1589 #if 0
1590         /* What error should we return now? EUNATTACH? */
1591         if (pkt_sk(sk)->ifindex < 0)
1592                 return -ENODEV;
1593 #endif
1594
1595         if (flags & MSG_ERRQUEUE) {
1596                 err = packet_recv_error(sk, msg, len);
1597                 goto out;
1598         }
1599
1600         /*
1601          *      Call the generic datagram receiver. This handles all sorts
1602          *      of horrible races and re-entrancy so we can forget about it
1603          *      in the protocol layers.
1604          *
1605          *      Now it will return ENETDOWN, if device have just gone down,
1606          *      but then it will block.
1607          */
1608
1609         skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
1610
1611         /*
1612          *      An error occurred so return it. Because skb_recv_datagram()
1613          *      handles the blocking we don't see and worry about blocking
1614          *      retries.
1615          */
1616
1617         if (skb == NULL)
1618                 goto out;
1619
1620         if (pkt_sk(sk)->has_vnet_hdr) {
1621                 struct virtio_net_hdr vnet_hdr = { 0 };
1622
1623                 err = -EINVAL;
1624                 vnet_hdr_len = sizeof(vnet_hdr);
1625                 if (len < vnet_hdr_len)
1626                         goto out_free;
1627
1628                 len -= vnet_hdr_len;
1629
1630                 if (skb_is_gso(skb)) {
1631                         struct skb_shared_info *sinfo = skb_shinfo(skb);
1632
1633                         /* This is a hint as to how much should be linear. */
1634                         vnet_hdr.hdr_len = skb_headlen(skb);
1635                         vnet_hdr.gso_size = sinfo->gso_size;
1636                         if (sinfo->gso_type & SKB_GSO_TCPV4)
1637                                 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
1638                         else if (sinfo->gso_type & SKB_GSO_TCPV6)
1639                                 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
1640                         else if (sinfo->gso_type & SKB_GSO_UDP)
1641                                 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
1642                         else if (sinfo->gso_type & SKB_GSO_FCOE)
1643                                 goto out_free;
1644                         else
1645                                 BUG();
1646                         if (sinfo->gso_type & SKB_GSO_TCP_ECN)
1647                                 vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
1648                 } else
1649                         vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
1650
1651                 if (skb->ip_summed == CHECKSUM_PARTIAL) {
1652                         vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
1653                         vnet_hdr.csum_start = skb->csum_start -
1654                                                         skb_headroom(skb);
1655                         vnet_hdr.csum_offset = skb->csum_offset;
1656                 } /* else everything is zero */
1657
1658                 err = memcpy_toiovec(msg->msg_iov, (void *)&vnet_hdr,
1659                                      vnet_hdr_len);
1660                 if (err < 0)
1661                         goto out_free;
1662         }
1663
1664         /*
1665          *      If the address length field is there to be filled in, we fill
1666          *      it in now.
1667          */
1668
1669         sll = &PACKET_SKB_CB(skb)->sa.ll;
1670         if (sock->type == SOCK_PACKET)
1671                 msg->msg_namelen = sizeof(struct sockaddr_pkt);
1672         else
1673                 msg->msg_namelen = sll->sll_halen + offsetof(struct sockaddr_ll, sll_addr);
1674
1675         /*
1676          *      You lose any data beyond the buffer you gave. If it worries a
1677          *      user program they can ask the device for its MTU anyway.
1678          */
1679
1680         copied = skb->len;
1681         if (copied > len) {
1682                 copied = len;
1683                 msg->msg_flags |= MSG_TRUNC;
1684         }
1685
1686         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
1687         if (err)
1688                 goto out_free;
1689
1690         sock_recv_ts_and_drops(msg, sk, skb);
1691
1692         if (msg->msg_name)
1693                 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
1694                        msg->msg_namelen);
1695
1696         if (pkt_sk(sk)->auxdata) {
1697                 struct tpacket_auxdata aux;
1698
1699                 aux.tp_status = TP_STATUS_USER;
1700                 if (skb->ip_summed == CHECKSUM_PARTIAL)
1701                         aux.tp_status |= TP_STATUS_CSUMNOTREADY;
1702                 aux.tp_len = PACKET_SKB_CB(skb)->origlen;
1703                 aux.tp_snaplen = skb->len;
1704                 aux.tp_mac = 0;
1705                 aux.tp_net = skb_network_offset(skb);
1706                 aux.tp_vlan_tci = vlan_tx_tag_get(skb);
1707
1708                 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
1709         }
1710
1711         /*
1712          *      Free or return the buffer as appropriate. Again this
1713          *      hides all the races and re-entrancy issues from us.
1714          */
1715         err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
1716
1717 out_free:
1718         skb_free_datagram(sk, skb);
1719 out:
1720         return err;
1721 }
1722
1723 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
1724                                int *uaddr_len, int peer)
1725 {
1726         struct net_device *dev;
1727         struct sock *sk = sock->sk;
1728
1729         if (peer)
1730                 return -EOPNOTSUPP;
1731
1732         uaddr->sa_family = AF_PACKET;
1733         rcu_read_lock();
1734         dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
1735         if (dev)
1736                 strncpy(uaddr->sa_data, dev->name, 14);
1737         else
1738                 memset(uaddr->sa_data, 0, 14);
1739         rcu_read_unlock();
1740         *uaddr_len = sizeof(*uaddr);
1741
1742         return 0;
1743 }
1744
1745 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
1746                           int *uaddr_len, int peer)
1747 {
1748         struct net_device *dev;
1749         struct sock *sk = sock->sk;
1750         struct packet_sock *po = pkt_sk(sk);
1751         DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
1752
1753         if (peer)
1754                 return -EOPNOTSUPP;
1755
1756         sll->sll_family = AF_PACKET;
1757         sll->sll_ifindex = po->ifindex;
1758         sll->sll_protocol = po->num;
1759         sll->sll_pkttype = 0;
1760         rcu_read_lock();
1761         dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
1762         if (dev) {
1763                 sll->sll_hatype = dev->type;
1764                 sll->sll_halen = dev->addr_len;
1765                 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
1766         } else {
1767                 sll->sll_hatype = 0;    /* Bad: we have no ARPHRD_UNSPEC */
1768                 sll->sll_halen = 0;
1769         }
1770         rcu_read_unlock();
1771         *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
1772
1773         return 0;
1774 }
1775
1776 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
1777                          int what)
1778 {
1779         switch (i->type) {
1780         case PACKET_MR_MULTICAST:
1781                 if (i->alen != dev->addr_len)
1782                         return -EINVAL;
1783                 if (what > 0)
1784                         return dev_mc_add(dev, i->addr);
1785                 else
1786                         return dev_mc_del(dev, i->addr);
1787                 break;
1788         case PACKET_MR_PROMISC:
1789                 return dev_set_promiscuity(dev, what);
1790                 break;
1791         case PACKET_MR_ALLMULTI:
1792                 return dev_set_allmulti(dev, what);
1793                 break;
1794         case PACKET_MR_UNICAST:
1795                 if (i->alen != dev->addr_len)
1796                         return -EINVAL;
1797                 if (what > 0)
1798                         return dev_uc_add(dev, i->addr);
1799                 else
1800                         return dev_uc_del(dev, i->addr);
1801                 break;
1802         default:
1803                 break;
1804         }
1805         return 0;
1806 }
1807
1808 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
1809 {
1810         for ( ; i; i = i->next) {
1811                 if (i->ifindex == dev->ifindex)
1812                         packet_dev_mc(dev, i, what);
1813         }
1814 }
1815
1816 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
1817 {
1818         struct packet_sock *po = pkt_sk(sk);
1819         struct packet_mclist *ml, *i;
1820         struct net_device *dev;
1821         int err;
1822
1823         rtnl_lock();
1824
1825         err = -ENODEV;
1826         dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
1827         if (!dev)
1828                 goto done;
1829
1830         err = -EINVAL;
1831         if (mreq->mr_alen > dev->addr_len)
1832                 goto done;
1833
1834         err = -ENOBUFS;
1835         i = kmalloc(sizeof(*i), GFP_KERNEL);
1836         if (i == NULL)
1837                 goto done;
1838
1839         err = 0;
1840         for (ml = po->mclist; ml; ml = ml->next) {
1841                 if (ml->ifindex == mreq->mr_ifindex &&
1842                     ml->type == mreq->mr_type &&
1843                     ml->alen == mreq->mr_alen &&
1844                     memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
1845                         ml->count++;
1846                         /* Free the new element ... */
1847                         kfree(i);
1848                         goto done;
1849                 }
1850         }
1851
1852         i->type = mreq->mr_type;
1853         i->ifindex = mreq->mr_ifindex;
1854         i->alen = mreq->mr_alen;
1855         memcpy(i->addr, mreq->mr_address, i->alen);
1856         i->count = 1;
1857         i->next = po->mclist;
1858         po->mclist = i;
1859         err = packet_dev_mc(dev, i, 1);
1860         if (err) {
1861                 po->mclist = i->next;
1862                 kfree(i);
1863         }
1864
1865 done:
1866         rtnl_unlock();
1867         return err;
1868 }
1869
1870 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
1871 {
1872         struct packet_mclist *ml, **mlp;
1873
1874         rtnl_lock();
1875
1876         for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
1877                 if (ml->ifindex == mreq->mr_ifindex &&
1878                     ml->type == mreq->mr_type &&
1879                     ml->alen == mreq->mr_alen &&
1880                     memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
1881                         if (--ml->count == 0) {
1882                                 struct net_device *dev;
1883                                 *mlp = ml->next;
1884                                 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
1885                                 if (dev)
1886                                         packet_dev_mc(dev, ml, -1);
1887                                 kfree(ml);
1888                         }
1889                         rtnl_unlock();
1890                         return 0;
1891                 }
1892         }
1893         rtnl_unlock();
1894         return -EADDRNOTAVAIL;
1895 }
1896
1897 static void packet_flush_mclist(struct sock *sk)
1898 {
1899         struct packet_sock *po = pkt_sk(sk);
1900         struct packet_mclist *ml;
1901
1902         if (!po->mclist)
1903                 return;
1904
1905         rtnl_lock();
1906         while ((ml = po->mclist) != NULL) {
1907                 struct net_device *dev;
1908
1909                 po->mclist = ml->next;
1910                 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
1911                 if (dev != NULL)
1912                         packet_dev_mc(dev, ml, -1);
1913                 kfree(ml);
1914         }
1915         rtnl_unlock();
1916 }
1917
1918 static int
1919 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
1920 {
1921         struct sock *sk = sock->sk;
1922         struct packet_sock *po = pkt_sk(sk);
1923         int ret;
1924
1925         if (level != SOL_PACKET)
1926                 return -ENOPROTOOPT;
1927
1928         switch (optname) {
1929         case PACKET_ADD_MEMBERSHIP:
1930         case PACKET_DROP_MEMBERSHIP:
1931         {
1932                 struct packet_mreq_max mreq;
1933                 int len = optlen;
1934                 memset(&mreq, 0, sizeof(mreq));
1935                 if (len < sizeof(struct packet_mreq))
1936                         return -EINVAL;
1937                 if (len > sizeof(mreq))
1938                         len = sizeof(mreq);
1939                 if (copy_from_user(&mreq, optval, len))
1940                         return -EFAULT;
1941                 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
1942                         return -EINVAL;
1943                 if (optname == PACKET_ADD_MEMBERSHIP)
1944                         ret = packet_mc_add(sk, &mreq);
1945                 else
1946                         ret = packet_mc_drop(sk, &mreq);
1947                 return ret;
1948         }
1949
1950         case PACKET_RX_RING:
1951         case PACKET_TX_RING:
1952         {
1953                 struct tpacket_req req;
1954
1955                 if (optlen < sizeof(req))
1956                         return -EINVAL;
1957                 if (pkt_sk(sk)->has_vnet_hdr)
1958                         return -EINVAL;
1959                 if (copy_from_user(&req, optval, sizeof(req)))
1960                         return -EFAULT;
1961                 return packet_set_ring(sk, &req, 0, optname == PACKET_TX_RING);
1962         }
1963         case PACKET_COPY_THRESH:
1964         {
1965                 int val;
1966
1967                 if (optlen != sizeof(val))
1968                         return -EINVAL;
1969                 if (copy_from_user(&val, optval, sizeof(val)))
1970                         return -EFAULT;
1971
1972                 pkt_sk(sk)->copy_thresh = val;
1973                 return 0;
1974         }
1975         case PACKET_VERSION:
1976         {
1977                 int val;
1978
1979                 if (optlen != sizeof(val))
1980                         return -EINVAL;
1981                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
1982                         return -EBUSY;
1983                 if (copy_from_user(&val, optval, sizeof(val)))
1984                         return -EFAULT;
1985                 switch (val) {
1986                 case TPACKET_V1:
1987                 case TPACKET_V2:
1988                         po->tp_version = val;
1989                         return 0;
1990                 default:
1991                         return -EINVAL;
1992                 }
1993         }
1994         case PACKET_RESERVE:
1995         {
1996                 unsigned int val;
1997
1998                 if (optlen != sizeof(val))
1999                         return -EINVAL;
2000                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
2001                         return -EBUSY;
2002                 if (copy_from_user(&val, optval, sizeof(val)))
2003                         return -EFAULT;
2004                 po->tp_reserve = val;
2005                 return 0;
2006         }
2007         case PACKET_LOSS:
2008         {
2009                 unsigned int val;
2010
2011                 if (optlen != sizeof(val))
2012                         return -EINVAL;
2013                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
2014                         return -EBUSY;
2015                 if (copy_from_user(&val, optval, sizeof(val)))
2016                         return -EFAULT;
2017                 po->tp_loss = !!val;
2018                 return 0;
2019         }
2020         case PACKET_AUXDATA:
2021         {
2022                 int val;
2023
2024                 if (optlen < sizeof(val))
2025                         return -EINVAL;
2026                 if (copy_from_user(&val, optval, sizeof(val)))
2027                         return -EFAULT;
2028
2029                 po->auxdata = !!val;
2030                 return 0;
2031         }
2032         case PACKET_ORIGDEV:
2033         {
2034                 int val;
2035
2036                 if (optlen < sizeof(val))
2037                         return -EINVAL;
2038                 if (copy_from_user(&val, optval, sizeof(val)))
2039                         return -EFAULT;
2040
2041                 po->origdev = !!val;
2042                 return 0;
2043         }
2044         case PACKET_VNET_HDR:
2045         {
2046                 int val;
2047
2048                 if (sock->type != SOCK_RAW)
2049                         return -EINVAL;
2050                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
2051                         return -EBUSY;
2052                 if (optlen < sizeof(val))
2053                         return -EINVAL;
2054                 if (copy_from_user(&val, optval, sizeof(val)))
2055                         return -EFAULT;
2056
2057                 po->has_vnet_hdr = !!val;
2058                 return 0;
2059         }
2060         case PACKET_TIMESTAMP:
2061         {
2062                 int val;
2063
2064                 if (optlen != sizeof(val))
2065                         return -EINVAL;
2066                 if (copy_from_user(&val, optval, sizeof(val)))
2067                         return -EFAULT;
2068
2069                 po->tp_tstamp = val;
2070                 return 0;
2071         }
2072         default:
2073                 return -ENOPROTOOPT;
2074         }
2075 }
2076
2077 static int packet_getsockopt(struct socket *sock, int level, int optname,
2078                              char __user *optval, int __user *optlen)
2079 {
2080         int len;
2081         int val;
2082         struct sock *sk = sock->sk;
2083         struct packet_sock *po = pkt_sk(sk);
2084         void *data;
2085         struct tpacket_stats st;
2086
2087         if (level != SOL_PACKET)
2088                 return -ENOPROTOOPT;
2089
2090         if (get_user(len, optlen))
2091                 return -EFAULT;
2092
2093         if (len < 0)
2094                 return -EINVAL;
2095
2096         switch (optname) {
2097         case PACKET_STATISTICS:
2098                 if (len > sizeof(struct tpacket_stats))
2099                         len = sizeof(struct tpacket_stats);
2100                 spin_lock_bh(&sk->sk_receive_queue.lock);
2101                 st = po->stats;
2102                 memset(&po->stats, 0, sizeof(st));
2103                 spin_unlock_bh(&sk->sk_receive_queue.lock);
2104                 st.tp_packets += st.tp_drops;
2105
2106                 data = &st;
2107                 break;
2108         case PACKET_AUXDATA:
2109                 if (len > sizeof(int))
2110                         len = sizeof(int);
2111                 val = po->auxdata;
2112
2113                 data = &val;
2114                 break;
2115         case PACKET_ORIGDEV:
2116                 if (len > sizeof(int))
2117                         len = sizeof(int);
2118                 val = po->origdev;
2119
2120                 data = &val;
2121                 break;
2122         case PACKET_VNET_HDR:
2123                 if (len > sizeof(int))
2124                         len = sizeof(int);
2125                 val = po->has_vnet_hdr;
2126
2127                 data = &val;
2128                 break;
2129         case PACKET_VERSION:
2130                 if (len > sizeof(int))
2131                         len = sizeof(int);
2132                 val = po->tp_version;
2133                 data = &val;
2134                 break;
2135         case PACKET_HDRLEN:
2136                 if (len > sizeof(int))
2137                         len = sizeof(int);
2138                 if (copy_from_user(&val, optval, len))
2139                         return -EFAULT;
2140                 switch (val) {
2141                 case TPACKET_V1:
2142                         val = sizeof(struct tpacket_hdr);
2143                         break;
2144                 case TPACKET_V2:
2145                         val = sizeof(struct tpacket2_hdr);
2146                         break;
2147                 default:
2148                         return -EINVAL;
2149                 }
2150                 data = &val;
2151                 break;
2152         case PACKET_RESERVE:
2153                 if (len > sizeof(unsigned int))
2154                         len = sizeof(unsigned int);
2155                 val = po->tp_reserve;
2156                 data = &val;
2157                 break;
2158         case PACKET_LOSS:
2159                 if (len > sizeof(unsigned int))
2160                         len = sizeof(unsigned int);
2161                 val = po->tp_loss;
2162                 data = &val;
2163                 break;
2164         case PACKET_TIMESTAMP:
2165                 if (len > sizeof(int))
2166                         len = sizeof(int);
2167                 val = po->tp_tstamp;
2168                 data = &val;
2169                 break;
2170         default:
2171                 return -ENOPROTOOPT;
2172         }
2173
2174         if (put_user(len, optlen))
2175                 return -EFAULT;
2176         if (copy_to_user(optval, data, len))
2177                 return -EFAULT;
2178         return 0;
2179 }
2180
2181
2182 static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data)
2183 {
2184         struct sock *sk;
2185         struct hlist_node *node;
2186         struct net_device *dev = data;
2187         struct net *net = dev_net(dev);
2188
2189         rcu_read_lock();
2190         sk_for_each_rcu(sk, node, &net->packet.sklist) {
2191                 struct packet_sock *po = pkt_sk(sk);
2192
2193                 switch (msg) {
2194                 case NETDEV_UNREGISTER:
2195                         if (po->mclist)
2196                                 packet_dev_mclist(dev, po->mclist, -1);
2197                         /* fallthrough */
2198
2199                 case NETDEV_DOWN:
2200                         if (dev->ifindex == po->ifindex) {
2201                                 spin_lock(&po->bind_lock);
2202                                 if (po->running) {
2203                                         __dev_remove_pack(&po->prot_hook);
2204                                         __sock_put(sk);
2205                                         po->running = 0;
2206                                         sk->sk_err = ENETDOWN;
2207                                         if (!sock_flag(sk, SOCK_DEAD))
2208                                                 sk->sk_error_report(sk);
2209                                 }
2210                                 if (msg == NETDEV_UNREGISTER) {
2211                                         po->ifindex = -1;
2212                                         po->prot_hook.dev = NULL;
2213                                 }
2214                                 spin_unlock(&po->bind_lock);
2215                         }
2216                         break;
2217                 case NETDEV_UP:
2218                         if (dev->ifindex == po->ifindex) {
2219                                 spin_lock(&po->bind_lock);
2220                                 if (po->num && !po->running) {
2221                                         dev_add_pack(&po->prot_hook);
2222                                         sock_hold(sk);
2223                                         po->running = 1;
2224                                 }
2225                                 spin_unlock(&po->bind_lock);
2226                         }
2227                         break;
2228                 }
2229         }
2230         rcu_read_unlock();
2231         return NOTIFY_DONE;
2232 }
2233
2234
2235 static int packet_ioctl(struct socket *sock, unsigned int cmd,
2236                         unsigned long arg)
2237 {
2238         struct sock *sk = sock->sk;
2239
2240         switch (cmd) {
2241         case SIOCOUTQ:
2242         {
2243                 int amount = sk_wmem_alloc_get(sk);
2244
2245                 return put_user(amount, (int __user *)arg);
2246         }
2247         case SIOCINQ:
2248         {
2249                 struct sk_buff *skb;
2250                 int amount = 0;
2251
2252                 spin_lock_bh(&sk->sk_receive_queue.lock);
2253                 skb = skb_peek(&sk->sk_receive_queue);
2254                 if (skb)
2255                         amount = skb->len;
2256                 spin_unlock_bh(&sk->sk_receive_queue.lock);
2257                 return put_user(amount, (int __user *)arg);
2258         }
2259         case SIOCGSTAMP:
2260                 return sock_get_timestamp(sk, (struct timeval __user *)arg);
2261         case SIOCGSTAMPNS:
2262                 return sock_get_timestampns(sk, (struct timespec __user *)arg);
2263
2264 #ifdef CONFIG_INET
2265         case SIOCADDRT:
2266         case SIOCDELRT:
2267         case SIOCDARP:
2268         case SIOCGARP:
2269         case SIOCSARP:
2270         case SIOCGIFADDR:
2271         case SIOCSIFADDR:
2272         case SIOCGIFBRDADDR:
2273         case SIOCSIFBRDADDR:
2274         case SIOCGIFNETMASK:
2275         case SIOCSIFNETMASK:
2276         case SIOCGIFDSTADDR:
2277         case SIOCSIFDSTADDR:
2278         case SIOCSIFFLAGS:
2279                 return inet_dgram_ops.ioctl(sock, cmd, arg);
2280 #endif
2281
2282         default:
2283                 return -ENOIOCTLCMD;
2284         }
2285         return 0;
2286 }
2287
2288 static unsigned int packet_poll(struct file *file, struct socket *sock,
2289                                 poll_table *wait)
2290 {
2291         struct sock *sk = sock->sk;
2292         struct packet_sock *po = pkt_sk(sk);
2293         unsigned int mask = datagram_poll(file, sock, wait);
2294
2295         spin_lock_bh(&sk->sk_receive_queue.lock);
2296         if (po->rx_ring.pg_vec) {
2297                 if (!packet_previous_frame(po, &po->rx_ring, TP_STATUS_KERNEL))
2298                         mask |= POLLIN | POLLRDNORM;
2299         }
2300         spin_unlock_bh(&sk->sk_receive_queue.lock);
2301         spin_lock_bh(&sk->sk_write_queue.lock);
2302         if (po->tx_ring.pg_vec) {
2303                 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
2304                         mask |= POLLOUT | POLLWRNORM;
2305         }
2306         spin_unlock_bh(&sk->sk_write_queue.lock);
2307         return mask;
2308 }
2309
2310
2311 /* Dirty? Well, I still did not learn better way to account
2312  * for user mmaps.
2313  */
2314
2315 static void packet_mm_open(struct vm_area_struct *vma)
2316 {
2317         struct file *file = vma->vm_file;
2318         struct socket *sock = file->private_data;
2319         struct sock *sk = sock->sk;
2320
2321         if (sk)
2322                 atomic_inc(&pkt_sk(sk)->mapped);
2323 }
2324
2325 static void packet_mm_close(struct vm_area_struct *vma)
2326 {
2327         struct file *file = vma->vm_file;
2328         struct socket *sock = file->private_data;
2329         struct sock *sk = sock->sk;
2330
2331         if (sk)
2332                 atomic_dec(&pkt_sk(sk)->mapped);
2333 }
2334
2335 static const struct vm_operations_struct packet_mmap_ops = {
2336         .open   =       packet_mm_open,
2337         .close  =       packet_mm_close,
2338 };
2339
2340 static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
2341                         unsigned int len)
2342 {
2343         int i;
2344
2345         for (i = 0; i < len; i++) {
2346                 if (likely(pg_vec[i].buffer)) {
2347                         if (is_vmalloc_addr(pg_vec[i].buffer))
2348                                 vfree(pg_vec[i].buffer);
2349                         else
2350                                 free_pages((unsigned long)pg_vec[i].buffer,
2351                                            order);
2352                         pg_vec[i].buffer = NULL;
2353                 }
2354         }
2355         kfree(pg_vec);
2356 }
2357
2358 static inline char *alloc_one_pg_vec_page(unsigned long order)
2359 {
2360         char *buffer = NULL;
2361         gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
2362                           __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
2363
2364         buffer = (char *) __get_free_pages(gfp_flags, order);
2365
2366         if (buffer)
2367                 return buffer;
2368
2369         /*
2370          * __get_free_pages failed, fall back to vmalloc
2371          */
2372         buffer = vzalloc((1 << order) * PAGE_SIZE);
2373
2374         if (buffer)
2375                 return buffer;
2376
2377         /*
2378          * vmalloc failed, lets dig into swap here
2379          */
2380         gfp_flags &= ~__GFP_NORETRY;
2381         buffer = (char *)__get_free_pages(gfp_flags, order);
2382         if (buffer)
2383                 return buffer;
2384
2385         /*
2386          * complete and utter failure
2387          */
2388         return NULL;
2389 }
2390
2391 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
2392 {
2393         unsigned int block_nr = req->tp_block_nr;
2394         struct pgv *pg_vec;
2395         int i;
2396
2397         pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
2398         if (unlikely(!pg_vec))
2399                 goto out;
2400
2401         for (i = 0; i < block_nr; i++) {
2402                 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
2403                 if (unlikely(!pg_vec[i].buffer))
2404                         goto out_free_pgvec;
2405         }
2406
2407 out:
2408         return pg_vec;
2409
2410 out_free_pgvec:
2411         free_pg_vec(pg_vec, order, block_nr);
2412         pg_vec = NULL;
2413         goto out;
2414 }
2415
2416 static int packet_set_ring(struct sock *sk, struct tpacket_req *req,
2417                 int closing, int tx_ring)
2418 {
2419         struct pgv *pg_vec = NULL;
2420         struct packet_sock *po = pkt_sk(sk);
2421         int was_running, order = 0;
2422         struct packet_ring_buffer *rb;
2423         struct sk_buff_head *rb_queue;
2424         __be16 num;
2425         int err;
2426
2427         rb = tx_ring ? &po->tx_ring : &po->rx_ring;
2428         rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
2429
2430         err = -EBUSY;
2431         if (!closing) {
2432                 if (atomic_read(&po->mapped))
2433                         goto out;
2434                 if (atomic_read(&rb->pending))
2435                         goto out;
2436         }
2437
2438         if (req->tp_block_nr) {
2439                 /* Sanity tests and some calculations */
2440                 err = -EBUSY;
2441                 if (unlikely(rb->pg_vec))
2442                         goto out;
2443
2444                 switch (po->tp_version) {
2445                 case TPACKET_V1:
2446                         po->tp_hdrlen = TPACKET_HDRLEN;
2447                         break;
2448                 case TPACKET_V2:
2449                         po->tp_hdrlen = TPACKET2_HDRLEN;
2450                         break;
2451                 }
2452
2453                 err = -EINVAL;
2454                 if (unlikely((int)req->tp_block_size <= 0))
2455                         goto out;
2456                 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
2457                         goto out;
2458                 if (unlikely(req->tp_frame_size < po->tp_hdrlen +
2459                                         po->tp_reserve))
2460                         goto out;
2461                 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
2462                         goto out;
2463
2464                 rb->frames_per_block = req->tp_block_size/req->tp_frame_size;
2465                 if (unlikely(rb->frames_per_block <= 0))
2466                         goto out;
2467                 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
2468                                         req->tp_frame_nr))
2469                         goto out;
2470
2471                 err = -ENOMEM;
2472                 order = get_order(req->tp_block_size);
2473                 pg_vec = alloc_pg_vec(req, order);
2474                 if (unlikely(!pg_vec))
2475                         goto out;
2476         }
2477         /* Done */
2478         else {
2479                 err = -EINVAL;
2480                 if (unlikely(req->tp_frame_nr))
2481                         goto out;
2482         }
2483
2484         lock_sock(sk);
2485
2486         /* Detach socket from network */
2487         spin_lock(&po->bind_lock);
2488         was_running = po->running;
2489         num = po->num;
2490         if (was_running) {
2491                 __dev_remove_pack(&po->prot_hook);
2492                 po->num = 0;
2493                 po->running = 0;
2494                 __sock_put(sk);
2495         }
2496         spin_unlock(&po->bind_lock);
2497
2498         synchronize_net();
2499
2500         err = -EBUSY;
2501         mutex_lock(&po->pg_vec_lock);
2502         if (closing || atomic_read(&po->mapped) == 0) {
2503                 err = 0;
2504                 spin_lock_bh(&rb_queue->lock);
2505                 swap(rb->pg_vec, pg_vec);
2506                 rb->frame_max = (req->tp_frame_nr - 1);
2507                 rb->head = 0;
2508                 rb->frame_size = req->tp_frame_size;
2509                 spin_unlock_bh(&rb_queue->lock);
2510
2511                 swap(rb->pg_vec_order, order);
2512                 swap(rb->pg_vec_len, req->tp_block_nr);
2513
2514                 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
2515                 po->prot_hook.func = (po->rx_ring.pg_vec) ?
2516                                                 tpacket_rcv : packet_rcv;
2517                 skb_queue_purge(rb_queue);
2518                 if (atomic_read(&po->mapped))
2519                         pr_err("packet_mmap: vma is busy: %d\n",
2520                                atomic_read(&po->mapped));
2521         }
2522         mutex_unlock(&po->pg_vec_lock);
2523
2524         spin_lock(&po->bind_lock);
2525         if (was_running && !po->running) {
2526                 sock_hold(sk);
2527                 po->running = 1;
2528                 po->num = num;
2529                 dev_add_pack(&po->prot_hook);
2530         }
2531         spin_unlock(&po->bind_lock);
2532
2533         release_sock(sk);
2534
2535         if (pg_vec)
2536                 free_pg_vec(pg_vec, order, req->tp_block_nr);
2537 out:
2538         return err;
2539 }
2540
2541 static int packet_mmap(struct file *file, struct socket *sock,
2542                 struct vm_area_struct *vma)
2543 {
2544         struct sock *sk = sock->sk;
2545         struct packet_sock *po = pkt_sk(sk);
2546         unsigned long size, expected_size;
2547         struct packet_ring_buffer *rb;
2548         unsigned long start;
2549         int err = -EINVAL;
2550         int i;
2551
2552         if (vma->vm_pgoff)
2553                 return -EINVAL;
2554
2555         mutex_lock(&po->pg_vec_lock);
2556
2557         expected_size = 0;
2558         for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
2559                 if (rb->pg_vec) {
2560                         expected_size += rb->pg_vec_len
2561                                                 * rb->pg_vec_pages
2562                                                 * PAGE_SIZE;
2563                 }
2564         }
2565
2566         if (expected_size == 0)
2567                 goto out;
2568
2569         size = vma->vm_end - vma->vm_start;
2570         if (size != expected_size)
2571                 goto out;
2572
2573         start = vma->vm_start;
2574         for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
2575                 if (rb->pg_vec == NULL)
2576                         continue;
2577
2578                 for (i = 0; i < rb->pg_vec_len; i++) {
2579                         struct page *page;
2580                         void *kaddr = rb->pg_vec[i].buffer;
2581                         int pg_num;
2582
2583                         for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
2584                                 page = pgv_to_page(kaddr);
2585                                 err = vm_insert_page(vma, start, page);
2586                                 if (unlikely(err))
2587                                         goto out;
2588                                 start += PAGE_SIZE;
2589                                 kaddr += PAGE_SIZE;
2590                         }
2591                 }
2592         }
2593
2594         atomic_inc(&po->mapped);
2595         vma->vm_ops = &packet_mmap_ops;
2596         err = 0;
2597
2598 out:
2599         mutex_unlock(&po->pg_vec_lock);
2600         return err;
2601 }
2602
2603 static const struct proto_ops packet_ops_spkt = {
2604         .family =       PF_PACKET,
2605         .owner =        THIS_MODULE,
2606         .release =      packet_release,
2607         .bind =         packet_bind_spkt,
2608         .connect =      sock_no_connect,
2609         .socketpair =   sock_no_socketpair,
2610         .accept =       sock_no_accept,
2611         .getname =      packet_getname_spkt,
2612         .poll =         datagram_poll,
2613         .ioctl =        packet_ioctl,
2614         .listen =       sock_no_listen,
2615         .shutdown =     sock_no_shutdown,
2616         .setsockopt =   sock_no_setsockopt,
2617         .getsockopt =   sock_no_getsockopt,
2618         .sendmsg =      packet_sendmsg_spkt,
2619         .recvmsg =      packet_recvmsg,
2620         .mmap =         sock_no_mmap,
2621         .sendpage =     sock_no_sendpage,
2622 };
2623
2624 static const struct proto_ops packet_ops = {
2625         .family =       PF_PACKET,
2626         .owner =        THIS_MODULE,
2627         .release =      packet_release,
2628         .bind =         packet_bind,
2629         .connect =      sock_no_connect,
2630         .socketpair =   sock_no_socketpair,
2631         .accept =       sock_no_accept,
2632         .getname =      packet_getname,
2633         .poll =         packet_poll,
2634         .ioctl =        packet_ioctl,
2635         .listen =       sock_no_listen,
2636         .shutdown =     sock_no_shutdown,
2637         .setsockopt =   packet_setsockopt,
2638         .getsockopt =   packet_getsockopt,
2639         .sendmsg =      packet_sendmsg,
2640         .recvmsg =      packet_recvmsg,
2641         .mmap =         packet_mmap,
2642         .sendpage =     sock_no_sendpage,
2643 };
2644
2645 static const struct net_proto_family packet_family_ops = {
2646         .family =       PF_PACKET,
2647         .create =       packet_create,
2648         .owner  =       THIS_MODULE,
2649 };
2650
2651 static struct notifier_block packet_netdev_notifier = {
2652         .notifier_call =        packet_notifier,
2653 };
2654
2655 #ifdef CONFIG_PROC_FS
2656
2657 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
2658         __acquires(RCU)
2659 {
2660         struct net *net = seq_file_net(seq);
2661
2662         rcu_read_lock();
2663         return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
2664 }
2665
2666 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2667 {
2668         struct net *net = seq_file_net(seq);
2669         return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
2670 }
2671
2672 static void packet_seq_stop(struct seq_file *seq, void *v)
2673         __releases(RCU)
2674 {
2675         rcu_read_unlock();
2676 }
2677
2678 static int packet_seq_show(struct seq_file *seq, void *v)
2679 {
2680         if (v == SEQ_START_TOKEN)
2681                 seq_puts(seq, "sk       RefCnt Type Proto  Iface R Rmem   User   Inode\n");
2682         else {
2683                 struct sock *s = sk_entry(v);
2684                 const struct packet_sock *po = pkt_sk(s);
2685
2686                 seq_printf(seq,
2687                            "%p %-6d %-4d %04x   %-5d %1d %-6u %-6u %-6lu\n",
2688                            s,
2689                            atomic_read(&s->sk_refcnt),
2690                            s->sk_type,
2691                            ntohs(po->num),
2692                            po->ifindex,
2693                            po->running,
2694                            atomic_read(&s->sk_rmem_alloc),
2695                            sock_i_uid(s),
2696                            sock_i_ino(s));
2697         }
2698
2699         return 0;
2700 }
2701
2702 static const struct seq_operations packet_seq_ops = {
2703         .start  = packet_seq_start,
2704         .next   = packet_seq_next,
2705         .stop   = packet_seq_stop,
2706         .show   = packet_seq_show,
2707 };
2708
2709 static int packet_seq_open(struct inode *inode, struct file *file)
2710 {
2711         return seq_open_net(inode, file, &packet_seq_ops,
2712                             sizeof(struct seq_net_private));
2713 }
2714
2715 static const struct file_operations packet_seq_fops = {
2716         .owner          = THIS_MODULE,
2717         .open           = packet_seq_open,
2718         .read           = seq_read,
2719         .llseek         = seq_lseek,
2720         .release        = seq_release_net,
2721 };
2722
2723 #endif
2724
2725 static int __net_init packet_net_init(struct net *net)
2726 {
2727         spin_lock_init(&net->packet.sklist_lock);
2728         INIT_HLIST_HEAD(&net->packet.sklist);
2729
2730         if (!proc_net_fops_create(net, "packet", 0, &packet_seq_fops))
2731                 return -ENOMEM;
2732
2733         return 0;
2734 }
2735
2736 static void __net_exit packet_net_exit(struct net *net)
2737 {
2738         proc_net_remove(net, "packet");
2739 }
2740
2741 static struct pernet_operations packet_net_ops = {
2742         .init = packet_net_init,
2743         .exit = packet_net_exit,
2744 };
2745
2746
2747 static void __exit packet_exit(void)
2748 {
2749         unregister_netdevice_notifier(&packet_netdev_notifier);
2750         unregister_pernet_subsys(&packet_net_ops);
2751         sock_unregister(PF_PACKET);
2752         proto_unregister(&packet_proto);
2753 }
2754
2755 static int __init packet_init(void)
2756 {
2757         int rc = proto_register(&packet_proto, 0);
2758
2759         if (rc != 0)
2760                 goto out;
2761
2762         sock_register(&packet_family_ops);
2763         register_pernet_subsys(&packet_net_ops);
2764         register_netdevice_notifier(&packet_netdev_notifier);
2765 out:
2766         return rc;
2767 }
2768
2769 module_init(packet_init);
2770 module_exit(packet_exit);
2771 MODULE_LICENSE("GPL");
2772 MODULE_ALIAS_NETPROTO(PF_PACKET);