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  *              Chetan Loke     :       Implemented TPACKET_V3 block abstraction
  44  *                                      layer.
  45  *                                      Copyright (C) 2011, <lokec@ccs.neu.edu>
  46  *
  47  *
  48  *              This program is free software; you can redistribute it and/or
  49  *              modify it under the terms of the GNU General Public License
  50  *              as published by the Free Software Foundation; either version
  51  *              2 of the License, or (at your option) any later version.
  52  *
  53  */
  54
  55 #include <linux/types.h>
  56 #include <linux/mm.h>
  57 #include <linux/capability.h>
  58 #include <linux/fcntl.h>
  59 #include <linux/socket.h>
  60 #include <linux/in.h>
  61 #include <linux/inet.h>
  62 #include <linux/netdevice.h>
  63 #include <linux/if_packet.h>
  64 #include <linux/wireless.h>
  65 #include <linux/kernel.h>
  66 #include <linux/kmod.h>
  67 #include <linux/slab.h>
  68 #include <linux/vmalloc.h>
  69 #include <net/net_namespace.h>
  70 #include <net/ip.h>
  71 #include <net/protocol.h>
  72 #include <linux/skbuff.h>
  73 #include <net/sock.h>
  74 #include <linux/errno.h>
  75 #include <linux/timer.h>
  76 #include <asm/uaccess.h>
  77 #include <asm/ioctls.h>
  78 #include <asm/page.h>
  79 #include <asm/cacheflush.h>
  80 #include <asm/io.h>
  81 #include <linux/proc_fs.h>
  82 #include <linux/seq_file.h>
  83 #include <linux/poll.h>
  84 #include <linux/module.h>
  85 #include <linux/init.h>
  86 #include <linux/mutex.h>
  87 #include <linux/if_vlan.h>
  88 #include <linux/virtio_net.h>
  89 #include <linux/errqueue.h>
  90 #include <linux/net_tstamp.h>
  91 #include <linux/percpu.h>
  92 #ifdef CONFIG_INET
  93 #include <net/inet_common.h>
  94 #endif
  95
  96 #include "internal.h"
  97
  98 /*
  99    Assumptions:
 100    - if device has no dev->hard_header routine, it adds and removes ll header
 101      inside itself. In this case ll header is invisible outside of device,
 102      but higher levels still should reserve dev->hard_header_len.
 103      Some devices are enough clever to reallocate skb, when header
 104      will not fit to reserved space (tunnel), another ones are silly
 105      (PPP).
 106    - packet socket receives packets with pulled ll header,
 107      so that SOCK_RAW should push it back.
 108
 109 On receive:
 110 -----------
 111
 112 Incoming, dev->hard_header!=NULL
 113    mac_header -> ll header
 114    data       -> data
 115
 116 Outgoing, dev->hard_header!=NULL
 117    mac_header -> ll header
 118    data       -> ll header
 119
 120 Incoming, dev->hard_header==NULL
 121    mac_header -> UNKNOWN position. It is very likely, that it points to ll
 122                  header.  PPP makes it, that is wrong, because introduce
 123                  assymetry between rx and tx paths.
 124    data       -> data
 125
 126 Outgoing, dev->hard_header==NULL
 127    mac_header -> data. ll header is still not built!
 128    data       -> data
 129
 130 Resume
 131   If dev->hard_header==NULL we are unlikely to restore sensible ll header.
 132
 133
 134 On transmit:
 135 ------------
 136
 137 dev->hard_header != NULL
 138    mac_header -> ll header
 139    data       -> ll header
 140
 141 dev->hard_header == NULL (ll header is added by device, we cannot control it)
 142    mac_header -> data
 143    data       -> data
 144
 145    We should set nh.raw on output to correct posistion,
 146    packet classifier depends on it.
 147  */
 148
 149 /* Private packet socket structures. */
 150
 151 /* identical to struct packet_mreq except it has
 152  * a longer address field.
 153  */
 154 struct packet_mreq_max {
 155         int             mr_ifindex;
 156         unsigned short  mr_type;
 157         unsigned short  mr_alen;
 158         unsigned char   mr_address[MAX_ADDR_LEN];
 159 };
 160
 161 union tpacket_uhdr {
 162         struct tpacket_hdr  *h1;
 163         struct tpacket2_hdr *h2;
 164         struct tpacket3_hdr *h3;
 165         void *raw;
 166 };
 167
 168 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
 169                 int closing, int tx_ring);
 170
 171 #define V3_ALIGNMENT    (8)
 172
 173 #define BLK_HDR_LEN     (ALIGN(sizeof(struct tpacket_block_desc), V3_ALIGNMENT))
 174
 175 #define BLK_PLUS_PRIV(sz_of_priv) \
 176         (BLK_HDR_LEN + ALIGN((sz_of_priv), V3_ALIGNMENT))
 177
 178 #define PGV_FROM_VMALLOC 1
 179
 180 #define BLOCK_STATUS(x) ((x)->hdr.bh1.block_status)
 181 #define BLOCK_NUM_PKTS(x)       ((x)->hdr.bh1.num_pkts)
 182 #define BLOCK_O2FP(x)           ((x)->hdr.bh1.offset_to_first_pkt)
 183 #define BLOCK_LEN(x)            ((x)->hdr.bh1.blk_len)
 184 #define BLOCK_SNUM(x)           ((x)->hdr.bh1.seq_num)
 185 #define BLOCK_O2PRIV(x) ((x)->offset_to_priv)
 186 #define BLOCK_PRIV(x)           ((void *)((char *)(x) + BLOCK_O2PRIV(x)))
 187
 188 struct packet_sock;
 189 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg);
 190 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
 191                        struct packet_type *pt, struct net_device *orig_dev);
 192
 193 static void *packet_previous_frame(struct packet_sock *po,
 194                 struct packet_ring_buffer *rb,
 195                 int status);
 196 static void packet_increment_head(struct packet_ring_buffer *buff);
 197 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *,
 198                         struct tpacket_block_desc *);
 199 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *,
 200                         struct packet_sock *);
 201 static void prb_retire_current_block(struct tpacket_kbdq_core *,
 202                 struct packet_sock *, unsigned int status);
 203 static int prb_queue_frozen(struct tpacket_kbdq_core *);
 204 static void prb_open_block(struct tpacket_kbdq_core *,
 205                 struct tpacket_block_desc *);
 206 static void prb_retire_rx_blk_timer_expired(unsigned long);
 207 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *);
 208 static void prb_init_blk_timer(struct packet_sock *,
 209                 struct tpacket_kbdq_core *,
 210                 void (*func) (unsigned long));
 211 static void prb_fill_rxhash(struct tpacket_kbdq_core *, struct tpacket3_hdr *);
 212 static void prb_clear_rxhash(struct tpacket_kbdq_core *,
 213                 struct tpacket3_hdr *);
 214 static void prb_fill_vlan_info(struct tpacket_kbdq_core *,
 215                 struct tpacket3_hdr *);
 216 static void packet_flush_mclist(struct sock *sk);
 217
 218 struct packet_skb_cb {
 219         unsigned int origlen;
 220         union {
 221                 struct sockaddr_pkt pkt;
 222                 struct sockaddr_ll ll;
 223         } sa;
 224 };
 225
 226 #define PACKET_SKB_CB(__skb)    ((struct packet_skb_cb *)((__skb)->cb))
 227
 228 #define GET_PBDQC_FROM_RB(x)    ((struct tpacket_kbdq_core *)(&(x)->prb_bdqc))
 229 #define GET_PBLOCK_DESC(x, bid) \
 230         ((struct tpacket_block_desc *)((x)->pkbdq[(bid)].buffer))
 231 #define GET_CURR_PBLOCK_DESC_FROM_CORE(x)       \
 232         ((struct tpacket_block_desc *)((x)->pkbdq[(x)->kactive_blk_num].buffer))
 233 #define GET_NEXT_PRB_BLK_NUM(x) \
 234         (((x)->kactive_blk_num < ((x)->knum_blocks-1)) ? \
 235         ((x)->kactive_blk_num+1) : 0)
 236
 237 static void __fanout_unlink(struct sock *sk, struct packet_sock *po);
 238 static void __fanout_link(struct sock *sk, struct packet_sock *po);
 239
 240 static int packet_direct_xmit(struct sk_buff *skb)
 241 {
 242         struct net_device *dev = skb->dev;
 243         const struct net_device_ops *ops = dev->netdev_ops;
 244         netdev_features_t features;
 245         struct netdev_queue *txq;
 246         u16 queue_map;
 247         int ret;
 248
 249         if (unlikely(!netif_running(dev) ||
 250                      !netif_carrier_ok(dev))) {
 251                 kfree_skb(skb);
 252                 return NET_XMIT_DROP;
 253         }
 254
 255         features = netif_skb_features(skb);
 256         if (skb_needs_linearize(skb, features) &&
 257             __skb_linearize(skb)) {
 258                 kfree_skb(skb);
 259                 return NET_XMIT_DROP;
 260         }
 261
 262         queue_map = skb_get_queue_mapping(skb);
 263         txq = netdev_get_tx_queue(dev, queue_map);
 264
 265         __netif_tx_lock_bh(txq);
 266         if (unlikely(netif_xmit_frozen_or_stopped(txq))) {
 267                 ret = NETDEV_TX_BUSY;
 268                 kfree_skb(skb);
 269                 goto out;
 270         }
 271
 272         ret = ops->ndo_start_xmit(skb, dev);
 273         if (likely(dev_xmit_complete(ret)))
 274                 txq_trans_update(txq);
 275         else
 276                 kfree_skb(skb);
 277 out:
 278         __netif_tx_unlock_bh(txq);
 279         return ret;
 280 }
 281
 282 static struct net_device *packet_cached_dev_get(struct packet_sock *po)
 283 {
 284         struct net_device *dev;
 285
 286         rcu_read_lock();
 287         dev = rcu_dereference(po->cached_dev);
 288         if (likely(dev))
 289                 dev_hold(dev);
 290         rcu_read_unlock();
 291
 292         return dev;
 293 }
 294
 295 static void packet_cached_dev_assign(struct packet_sock *po,
 296                                      struct net_device *dev)
 297 {
 298         rcu_assign_pointer(po->cached_dev, dev);
 299 }
 300
 301 static void packet_cached_dev_reset(struct packet_sock *po)
 302 {
 303         RCU_INIT_POINTER(po->cached_dev, NULL);
 304 }
 305
 306 static bool packet_use_direct_xmit(const struct packet_sock *po)
 307 {
 308         return po->xmit == packet_direct_xmit;
 309 }
 310
 311 static u16 __packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
 312 {
 313         return (u16) raw_smp_processor_id() % dev->real_num_tx_queues;
 314 }
 315
 316 static void packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
 317 {
 318         const struct net_device_ops *ops = dev->netdev_ops;
 319         u16 queue_index;
 320
 321         if (ops->ndo_select_queue) {
 322                 queue_index = ops->ndo_select_queue(dev, skb, NULL,
 323                                                     __packet_pick_tx_queue);
 324                 queue_index = netdev_cap_txqueue(dev, queue_index);
 325         } else {
 326                 queue_index = __packet_pick_tx_queue(dev, skb);
 327         }
 328
 329         skb_set_queue_mapping(skb, queue_index);
 330 }
 331
 332 /* register_prot_hook must be invoked with the po->bind_lock held,
 333  * or from a context in which asynchronous accesses to the packet
 334  * socket is not possible (packet_create()).
 335  */
 336 static void register_prot_hook(struct sock *sk)
 337 {
 338         struct packet_sock *po = pkt_sk(sk);
 339
 340         if (!po->running) {
 341                 if (po->fanout)
 342                         __fanout_link(sk, po);
 343                 else
 344                         dev_add_pack(&po->prot_hook);
 345
 346                 sock_hold(sk);
 347                 po->running = 1;
 348         }
 349 }
 350
 351 /* {,__}unregister_prot_hook() must be invoked with the po->bind_lock
 352  * held.   If the sync parameter is true, we will temporarily drop
 353  * the po->bind_lock and do a synchronize_net to make sure no
 354  * asynchronous packet processing paths still refer to the elements
 355  * of po->prot_hook.  If the sync parameter is false, it is the
 356  * callers responsibility to take care of this.
 357  */
 358 static void __unregister_prot_hook(struct sock *sk, bool sync)
 359 {
 360         struct packet_sock *po = pkt_sk(sk);
 361
 362         po->running = 0;
 363
 364         if (po->fanout)
 365                 __fanout_unlink(sk, po);
 366         else
 367                 __dev_remove_pack(&po->prot_hook);
 368
 369         __sock_put(sk);
 370
 371         if (sync) {
 372                 spin_unlock(&po->bind_lock);
 373                 synchronize_net();
 374                 spin_lock(&po->bind_lock);
 375         }
 376 }
 377
 378 static void unregister_prot_hook(struct sock *sk, bool sync)
 379 {
 380         struct packet_sock *po = pkt_sk(sk);
 381
 382         if (po->running)
 383                 __unregister_prot_hook(sk, sync);
 384 }
 385
 386 static inline __pure struct page *pgv_to_page(void *addr)
 387 {
 388         if (is_vmalloc_addr(addr))
 389                 return vmalloc_to_page(addr);
 390         return virt_to_page(addr);
 391 }
 392
 393 static void __packet_set_status(struct packet_sock *po, void *frame, int status)
 394 {
 395         union tpacket_uhdr h;
 396
 397         h.raw = frame;
 398         switch (po->tp_version) {
 399         case TPACKET_V1:
 400                 h.h1->tp_status = status;
 401                 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
 402                 break;
 403         case TPACKET_V2:
 404                 h.h2->tp_status = status;
 405                 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
 406                 break;
 407         case TPACKET_V3:
 408         default:
 409                 WARN(1, "TPACKET version not supported.\n");
 410                 BUG();
 411         }
 412
 413         smp_wmb();
 414 }
 415
 416 static int __packet_get_status(struct packet_sock *po, void *frame)
 417 {
 418         union tpacket_uhdr h;
 419
 420         smp_rmb();
 421
 422         h.raw = frame;
 423         switch (po->tp_version) {
 424         case TPACKET_V1:
 425                 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
 426                 return h.h1->tp_status;
 427         case TPACKET_V2:
 428                 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
 429                 return h.h2->tp_status;
 430         case TPACKET_V3:
 431         default:
 432                 WARN(1, "TPACKET version not supported.\n");
 433                 BUG();
 434                 return 0;
 435         }
 436 }
 437
 438 static __u32 tpacket_get_timestamp(struct sk_buff *skb, struct timespec *ts,
 439                                    unsigned int flags)
 440 {
 441         struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
 442
 443         if (shhwtstamps) {
 444                 if ((flags & SOF_TIMESTAMPING_SYS_HARDWARE) &&
 445                     ktime_to_timespec_cond(shhwtstamps->syststamp, ts))
 446                         return TP_STATUS_TS_SYS_HARDWARE;
 447                 if ((flags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
 448                     ktime_to_timespec_cond(shhwtstamps->hwtstamp, ts))
 449                         return TP_STATUS_TS_RAW_HARDWARE;
 450         }
 451
 452         if (ktime_to_timespec_cond(skb->tstamp, ts))
 453                 return TP_STATUS_TS_SOFTWARE;
 454
 455         return 0;
 456 }
 457
 458 static __u32 __packet_set_timestamp(struct packet_sock *po, void *frame,
 459                                     struct sk_buff *skb)
 460 {
 461         union tpacket_uhdr h;
 462         struct timespec ts;
 463         __u32 ts_status;
 464
 465         if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
 466                 return 0;
 467
 468         h.raw = frame;
 469         switch (po->tp_version) {
 470         case TPACKET_V1:
 471                 h.h1->tp_sec = ts.tv_sec;
 472                 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
 473                 break;
 474         case TPACKET_V2:
 475                 h.h2->tp_sec = ts.tv_sec;
 476                 h.h2->tp_nsec = ts.tv_nsec;
 477                 break;
 478         case TPACKET_V3:
 479         default:
 480                 WARN(1, "TPACKET version not supported.\n");
 481                 BUG();
 482         }
 483
 484         /* one flush is safe, as both fields always lie on the same cacheline */
 485         flush_dcache_page(pgv_to_page(&h.h1->tp_sec));
 486         smp_wmb();
 487
 488         return ts_status;
 489 }
 490
 491 static void *packet_lookup_frame(struct packet_sock *po,
 492                 struct packet_ring_buffer *rb,
 493                 unsigned int position,
 494                 int status)
 495 {
 496         unsigned int pg_vec_pos, frame_offset;
 497         union tpacket_uhdr h;
 498
 499         pg_vec_pos = position / rb->frames_per_block;
 500         frame_offset = position % rb->frames_per_block;
 501
 502         h.raw = rb->pg_vec[pg_vec_pos].buffer +
 503                 (frame_offset * rb->frame_size);
 504
 505         if (status != __packet_get_status(po, h.raw))
 506                 return NULL;
 507
 508         return h.raw;
 509 }
 510
 511 static void *packet_current_frame(struct packet_sock *po,
 512                 struct packet_ring_buffer *rb,
 513                 int status)
 514 {
 515         return packet_lookup_frame(po, rb, rb->head, status);
 516 }
 517
 518 static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc)
 519 {
 520         del_timer_sync(&pkc->retire_blk_timer);
 521 }
 522
 523 static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
 524                 int tx_ring,
 525                 struct sk_buff_head *rb_queue)
 526 {
 527         struct tpacket_kbdq_core *pkc;
 528
 529         pkc = tx_ring ? GET_PBDQC_FROM_RB(&po->tx_ring) :
 530                         GET_PBDQC_FROM_RB(&po->rx_ring);
 531
 532         spin_lock_bh(&rb_queue->lock);
 533         pkc->delete_blk_timer = 1;
 534         spin_unlock_bh(&rb_queue->lock);
 535
 536         prb_del_retire_blk_timer(pkc);
 537 }
 538
 539 static void prb_init_blk_timer(struct packet_sock *po,
 540                 struct tpacket_kbdq_core *pkc,
 541                 void (*func) (unsigned long))
 542 {
 543         init_timer(&pkc->retire_blk_timer);
 544         pkc->retire_blk_timer.data = (long)po;
 545         pkc->retire_blk_timer.function = func;
 546         pkc->retire_blk_timer.expires = jiffies;
 547 }
 548
 549 static void prb_setup_retire_blk_timer(struct packet_sock *po, int tx_ring)
 550 {
 551         struct tpacket_kbdq_core *pkc;
 552
 553         if (tx_ring)
 554                 BUG();
 555
 556         pkc = tx_ring ? GET_PBDQC_FROM_RB(&po->tx_ring) :
 557                         GET_PBDQC_FROM_RB(&po->rx_ring);
 558         prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired);
 559 }
 560
 561 static int prb_calc_retire_blk_tmo(struct packet_sock *po,
 562                                 int blk_size_in_bytes)
 563 {
 564         struct net_device *dev;
 565         unsigned int mbits = 0, msec = 0, div = 0, tmo = 0;
 566         struct ethtool_cmd ecmd;
 567         int err;
 568         u32 speed;
 569
 570         rtnl_lock();
 571         dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex);
 572         if (unlikely(!dev)) {
 573                 rtnl_unlock();
 574                 return DEFAULT_PRB_RETIRE_TOV;
 575         }
 576         err = __ethtool_get_settings(dev, &ecmd);
 577         speed = ethtool_cmd_speed(&ecmd);
 578         rtnl_unlock();
 579         if (!err) {
 580                 /*
 581                  * If the link speed is so slow you don't really
 582                  * need to worry about perf anyways
 583                  */
 584                 if (speed < SPEED_1000 || speed == SPEED_UNKNOWN) {
 585                         return DEFAULT_PRB_RETIRE_TOV;
 586                 } else {
 587                         msec = 1;
 588                         div = speed / 1000;
 589                 }
 590         }
 591
 592         mbits = (blk_size_in_bytes * 8) / (1024 * 1024);
 593
 594         if (div)
 595                 mbits /= div;
 596
 597         tmo = mbits * msec;
 598
 599         if (div)
 600                 return tmo+1;
 601         return tmo;
 602 }
 603
 604 static void prb_init_ft_ops(struct tpacket_kbdq_core *p1,
 605                         union tpacket_req_u *req_u)
 606 {
 607         p1->feature_req_word = req_u->req3.tp_feature_req_word;
 608 }
 609
 610 static void init_prb_bdqc(struct packet_sock *po,
 611                         struct packet_ring_buffer *rb,
 612                         struct pgv *pg_vec,
 613                         union tpacket_req_u *req_u, int tx_ring)
 614 {
 615         struct tpacket_kbdq_core *p1 = GET_PBDQC_FROM_RB(rb);
 616         struct tpacket_block_desc *pbd;
 617
 618         memset(p1, 0x0, sizeof(*p1));
 619
 620         p1->knxt_seq_num = 1;
 621         p1->pkbdq = pg_vec;
 622         pbd = (struct tpacket_block_desc *)pg_vec[0].buffer;
 623         p1->pkblk_start = pg_vec[0].buffer;
 624         p1->kblk_size = req_u->req3.tp_block_size;
 625         p1->knum_blocks = req_u->req3.tp_block_nr;
 626         p1->hdrlen = po->tp_hdrlen;
 627         p1->version = po->tp_version;
 628         p1->last_kactive_blk_num = 0;
 629         po->stats.stats3.tp_freeze_q_cnt = 0;
 630         if (req_u->req3.tp_retire_blk_tov)
 631                 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
 632         else
 633                 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
 634                                                 req_u->req3.tp_block_size);
 635         p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
 636         p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;
 637
 638         prb_init_ft_ops(p1, req_u);
 639         prb_setup_retire_blk_timer(po, tx_ring);
 640         prb_open_block(p1, pbd);
 641 }
 642
 643 /*  Do NOT update the last_blk_num first.
 644  *  Assumes sk_buff_head lock is held.
 645  */
 646 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
 647 {
 648         mod_timer(&pkc->retire_blk_timer,
 649                         jiffies + pkc->tov_in_jiffies);
 650         pkc->last_kactive_blk_num = pkc->kactive_blk_num;
 651 }
 652
 653 /*
 654  * Timer logic:
 655  * 1) We refresh the timer only when we open a block.
 656  *    By doing this we don't waste cycles refreshing the timer
 657  *        on packet-by-packet basis.
 658  *
 659  * With a 1MB block-size, on a 1Gbps line, it will take
 660  * i) ~8 ms to fill a block + ii) memcpy etc.
 661  * In this cut we are not accounting for the memcpy time.
 662  *
 663  * So, if the user sets the 'tmo' to 10ms then the timer
 664  * will never fire while the block is still getting filled
 665  * (which is what we want). However, the user could choose
 666  * to close a block early and that's fine.
 667  *
 668  * But when the timer does fire, we check whether or not to refresh it.
 669  * Since the tmo granularity is in msecs, it is not too expensive
 670  * to refresh the timer, lets say every '8' msecs.
 671  * Either the user can set the 'tmo' or we can derive it based on
 672  * a) line-speed and b) block-size.
 673  * prb_calc_retire_blk_tmo() calculates the tmo.
 674  *
 675  */
 676 static void prb_retire_rx_blk_timer_expired(unsigned long data)
 677 {
 678         struct packet_sock *po = (struct packet_sock *)data;
 679         struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
 680         unsigned int frozen;
 681         struct tpacket_block_desc *pbd;
 682
 683         spin_lock(&po->sk.sk_receive_queue.lock);
 684
 685         frozen = prb_queue_frozen(pkc);
 686         pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
 687
 688         if (unlikely(pkc->delete_blk_timer))
 689                 goto out;
 690
 691         /* We only need to plug the race when the block is partially filled.
 692          * tpacket_rcv:
 693          *              lock(); increment BLOCK_NUM_PKTS; unlock()
 694          *              copy_bits() is in progress ...
 695          *              timer fires on other cpu:
 696          *              we can't retire the current block because copy_bits
 697          *              is in progress.
 698          *
 699          */
 700         if (BLOCK_NUM_PKTS(pbd)) {
 701                 while (atomic_read(&pkc->blk_fill_in_prog)) {
 702                         /* Waiting for skb_copy_bits to finish... */
 703                         cpu_relax();
 704                 }
 705         }
 706
 707         if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) {
 708                 if (!frozen) {
 709                         prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
 710                         if (!prb_dispatch_next_block(pkc, po))
 711                                 goto refresh_timer;
 712                         else
 713                                 goto out;
 714                 } else {
 715                         /* Case 1. Queue was frozen because user-space was
 716                          *         lagging behind.
 717                          */
 718                         if (prb_curr_blk_in_use(pkc, pbd)) {
 719                                 /*
 720                                  * Ok, user-space is still behind.
 721                                  * So just refresh the timer.
 722                                  */
 723                                 goto refresh_timer;
 724                         } else {
 725                                /* Case 2. queue was frozen,user-space caught up,
 726                                 * now the link went idle && the timer fired.
 727                                 * We don't have a block to close.So we open this
 728                                 * block and restart the timer.
 729                                 * opening a block thaws the queue,restarts timer
 730                                 * Thawing/timer-refresh is a side effect.
 731                                 */
 732                                 prb_open_block(pkc, pbd);
 733                                 goto out;
 734                         }
 735                 }
 736         }
 737
 738 refresh_timer:
 739         _prb_refresh_rx_retire_blk_timer(pkc);
 740
 741 out:
 742         spin_unlock(&po->sk.sk_receive_queue.lock);
 743 }
 744
 745 static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
 746                 struct tpacket_block_desc *pbd1, __u32 status)
 747 {
 748         /* Flush everything minus the block header */
 749
 750 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
 751         u8 *start, *end;
 752
 753         start = (u8 *)pbd1;
 754
 755         /* Skip the block header(we know header WILL fit in 4K) */
 756         start += PAGE_SIZE;
 757
 758         end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end);
 759         for (; start < end; start += PAGE_SIZE)
 760                 flush_dcache_page(pgv_to_page(start));
 761
 762         smp_wmb();
 763 #endif
 764
 765         /* Now update the block status. */
 766
 767         BLOCK_STATUS(pbd1) = status;
 768
 769         /* Flush the block header */
 770
 771 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
 772         start = (u8 *)pbd1;
 773         flush_dcache_page(pgv_to_page(start));
 774
 775         smp_wmb();
 776 #endif
 777 }
 778
 779 /*
 780  * Side effect:
 781  *
 782  * 1) flush the block
 783  * 2) Increment active_blk_num
 784  *
 785  * Note:We DONT refresh the timer on purpose.
 786  *      Because almost always the next block will be opened.
 787  */
 788 static void prb_close_block(struct tpacket_kbdq_core *pkc1,
 789                 struct tpacket_block_desc *pbd1,
 790                 struct packet_sock *po, unsigned int stat)
 791 {
 792         __u32 status = TP_STATUS_USER | stat;
 793
 794         struct tpacket3_hdr *last_pkt;
 795         struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
 796
 797         if (po->stats.stats3.tp_drops)
 798                 status |= TP_STATUS_LOSING;
 799
 800         last_pkt = (struct tpacket3_hdr *)pkc1->prev;
 801         last_pkt->tp_next_offset = 0;
 802
 803         /* Get the ts of the last pkt */
 804         if (BLOCK_NUM_PKTS(pbd1)) {
 805                 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec;
 806                 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec;
 807         } else {
 808                 /* Ok, we tmo'd - so get the current time */
 809                 struct timespec ts;
 810                 getnstimeofday(&ts);
 811                 h1->ts_last_pkt.ts_sec = ts.tv_sec;
 812                 h1->ts_last_pkt.ts_nsec = ts.tv_nsec;
 813         }
 814
 815         smp_wmb();
 816
 817         /* Flush the block */
 818         prb_flush_block(pkc1, pbd1, status);
 819
 820         pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1);
 821 }
 822
 823 static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
 824 {
 825         pkc->reset_pending_on_curr_blk = 0;
 826 }
 827
 828 /*
 829  * Side effect of opening a block:
 830  *
 831  * 1) prb_queue is thawed.
 832  * 2) retire_blk_timer is refreshed.
 833  *
 834  */
 835 static void prb_open_block(struct tpacket_kbdq_core *pkc1,
 836         struct tpacket_block_desc *pbd1)
 837 {
 838         struct timespec ts;
 839         struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
 840
 841         smp_rmb();
 842
 843         /* We could have just memset this but we will lose the
 844          * flexibility of making the priv area sticky
 845          */
 846
 847         BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
 848         BLOCK_NUM_PKTS(pbd1) = 0;
 849         BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
 850
 851         getnstimeofday(&ts);
 852
 853         h1->ts_first_pkt.ts_sec = ts.tv_sec;
 854         h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
 855
 856         pkc1->pkblk_start = (char *)pbd1;
 857         pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
 858
 859         BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
 860         BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN;
 861
 862         pbd1->version = pkc1->version;
 863         pkc1->prev = pkc1->nxt_offset;
 864         pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;
 865
 866         prb_thaw_queue(pkc1);
 867         _prb_refresh_rx_retire_blk_timer(pkc1);
 868
 869         smp_wmb();
 870 }
 871
 872 /*
 873  * Queue freeze logic:
 874  * 1) Assume tp_block_nr = 8 blocks.
 875  * 2) At time 't0', user opens Rx ring.
 876  * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7
 877  * 4) user-space is either sleeping or processing block '0'.
 878  * 5) tpacket_rcv is currently filling block '7', since there is no space left,
 879  *    it will close block-7,loop around and try to fill block '0'.
 880  *    call-flow:
 881  *    __packet_lookup_frame_in_block
 882  *      prb_retire_current_block()
 883  *      prb_dispatch_next_block()
 884  *        |->(BLOCK_STATUS == USER) evaluates to true
 885  *    5.1) Since block-0 is currently in-use, we just freeze the queue.
 886  * 6) Now there are two cases:
 887  *    6.1) Link goes idle right after the queue is frozen.
 888  *         But remember, the last open_block() refreshed the timer.
 889  *         When this timer expires,it will refresh itself so that we can
 890  *         re-open block-0 in near future.
 891  *    6.2) Link is busy and keeps on receiving packets. This is a simple
 892  *         case and __packet_lookup_frame_in_block will check if block-0
 893  *         is free and can now be re-used.
 894  */
 895 static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
 896                                   struct packet_sock *po)
 897 {
 898         pkc->reset_pending_on_curr_blk = 1;
 899         po->stats.stats3.tp_freeze_q_cnt++;
 900 }
 901
 902 #define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT))
 903
 904 /*
 905  * If the next block is free then we will dispatch it
 906  * and return a good offset.
 907  * Else, we will freeze the queue.
 908  * So, caller must check the return value.
 909  */
 910 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
 911                 struct packet_sock *po)
 912 {
 913         struct tpacket_block_desc *pbd;
 914
 915         smp_rmb();
 916
 917         /* 1. Get current block num */
 918         pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
 919
 920         /* 2. If this block is currently in_use then freeze the queue */
 921         if (TP_STATUS_USER & BLOCK_STATUS(pbd)) {
 922                 prb_freeze_queue(pkc, po);
 923                 return NULL;
 924         }
 925
 926         /*
 927          * 3.
 928          * open this block and return the offset where the first packet
 929          * needs to get stored.
 930          */
 931         prb_open_block(pkc, pbd);
 932         return (void *)pkc->nxt_offset;
 933 }
 934
 935 static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
 936                 struct packet_sock *po, unsigned int status)
 937 {
 938         struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
 939
 940         /* retire/close the current block */
 941         if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) {
 942                 /*
 943                  * Plug the case where copy_bits() is in progress on
 944                  * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't
 945                  * have space to copy the pkt in the current block and
 946                  * called prb_retire_current_block()
 947                  *
 948                  * We don't need to worry about the TMO case because
 949                  * the timer-handler already handled this case.
 950                  */
 951                 if (!(status & TP_STATUS_BLK_TMO)) {
 952                         while (atomic_read(&pkc->blk_fill_in_prog)) {
 953                                 /* Waiting for skb_copy_bits to finish... */
 954                                 cpu_relax();
 955                         }
 956                 }
 957                 prb_close_block(pkc, pbd, po, status);
 958                 return;
 959         }
 960 }
 961
 962 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc,
 963                                       struct tpacket_block_desc *pbd)
 964 {
 965         return TP_STATUS_USER & BLOCK_STATUS(pbd);
 966 }
 967
 968 static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
 969 {
 970         return pkc->reset_pending_on_curr_blk;
 971 }
 972
 973 static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
 974 {
 975         struct tpacket_kbdq_core *pkc  = GET_PBDQC_FROM_RB(rb);
 976         atomic_dec(&pkc->blk_fill_in_prog);
 977 }
 978
 979 static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
 980                         struct tpacket3_hdr *ppd)
 981 {
 982         ppd->hv1.tp_rxhash = skb_get_hash(pkc->skb);
 983 }
 984
 985 static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
 986                         struct tpacket3_hdr *ppd)
 987 {
 988         ppd->hv1.tp_rxhash = 0;
 989 }
 990
 991 static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
 992                         struct tpacket3_hdr *ppd)
 993 {
 994         if (vlan_tx_tag_present(pkc->skb)) {
 995                 ppd->hv1.tp_vlan_tci = vlan_tx_tag_get(pkc->skb);
 996                 ppd->hv1.tp_vlan_tpid = ntohs(pkc->skb->vlan_proto);
 997                 ppd->tp_status = TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
 998         } else {
 999                 ppd->hv1.tp_vlan_tci = 0;
1000                 ppd->hv1.tp_vlan_tpid = 0;
1001                 ppd->tp_status = TP_STATUS_AVAILABLE;
1002         }
1003 }
1004
1005 static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
1006                         struct tpacket3_hdr *ppd)
1007 {
1008         ppd->hv1.tp_padding = 0;
1009         prb_fill_vlan_info(pkc, ppd);
1010
1011         if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH)
1012                 prb_fill_rxhash(pkc, ppd);
1013         else
1014                 prb_clear_rxhash(pkc, ppd);
1015 }
1016
1017 static void prb_fill_curr_block(char *curr,
1018                                 struct tpacket_kbdq_core *pkc,
1019                                 struct tpacket_block_desc *pbd,
1020                                 unsigned int len)
1021 {
1022         struct tpacket3_hdr *ppd;
1023
1024         ppd  = (struct tpacket3_hdr *)curr;
1025         ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len);
1026         pkc->prev = curr;
1027         pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len);
1028         BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len);
1029         BLOCK_NUM_PKTS(pbd) += 1;
1030         atomic_inc(&pkc->blk_fill_in_prog);
1031         prb_run_all_ft_ops(pkc, ppd);
1032 }
1033
1034 /* Assumes caller has the sk->rx_queue.lock */
1035 static void *__packet_lookup_frame_in_block(struct packet_sock *po,
1036                                             struct sk_buff *skb,
1037                                                 int status,
1038                                             unsigned int len
1039                                             )
1040 {
1041         struct tpacket_kbdq_core *pkc;
1042         struct tpacket_block_desc *pbd;
1043         char *curr, *end;
1044
1045         pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
1046         pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1047
1048         /* Queue is frozen when user space is lagging behind */
1049         if (prb_queue_frozen(pkc)) {
1050                 /*
1051                  * Check if that last block which caused the queue to freeze,
1052                  * is still in_use by user-space.
1053                  */
1054                 if (prb_curr_blk_in_use(pkc, pbd)) {
1055                         /* Can't record this packet */
1056                         return NULL;
1057                 } else {
1058                         /*
1059                          * Ok, the block was released by user-space.
1060                          * Now let's open that block.
1061                          * opening a block also thaws the queue.
1062                          * Thawing is a side effect.
1063                          */
1064                         prb_open_block(pkc, pbd);
1065                 }
1066         }
1067
1068         smp_mb();
1069         curr = pkc->nxt_offset;
1070         pkc->skb = skb;
1071         end = (char *)pbd + pkc->kblk_size;
1072
1073         /* first try the current block */
1074         if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) {
1075                 prb_fill_curr_block(curr, pkc, pbd, len);
1076                 return (void *)curr;
1077         }
1078
1079         /* Ok, close the current block */
1080         prb_retire_current_block(pkc, po, 0);
1081
1082         /* Now, try to dispatch the next block */
1083         curr = (char *)prb_dispatch_next_block(pkc, po);
1084         if (curr) {
1085                 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1086                 prb_fill_curr_block(curr, pkc, pbd, len);
1087                 return (void *)curr;
1088         }
1089
1090         /*
1091          * No free blocks are available.user_space hasn't caught up yet.
1092          * Queue was just frozen and now this packet will get dropped.
1093          */
1094         return NULL;
1095 }
1096
1097 static void *packet_current_rx_frame(struct packet_sock *po,
1098                                             struct sk_buff *skb,
1099                                             int status, unsigned int len)
1100 {
1101         char *curr = NULL;
1102         switch (po->tp_version) {
1103         case TPACKET_V1:
1104         case TPACKET_V2:
1105                 curr = packet_lookup_frame(po, &po->rx_ring,
1106                                         po->rx_ring.head, status);
1107                 return curr;
1108         case TPACKET_V3:
1109                 return __packet_lookup_frame_in_block(po, skb, status, len);
1110         default:
1111                 WARN(1, "TPACKET version not supported\n");
1112                 BUG();
1113                 return NULL;
1114         }
1115 }
1116
1117 static void *prb_lookup_block(struct packet_sock *po,
1118                                      struct packet_ring_buffer *rb,
1119                                      unsigned int idx,
1120                                      int status)
1121 {
1122         struct tpacket_kbdq_core *pkc  = GET_PBDQC_FROM_RB(rb);
1123         struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, idx);
1124
1125         if (status != BLOCK_STATUS(pbd))
1126                 return NULL;
1127         return pbd;
1128 }
1129
1130 static int prb_previous_blk_num(struct packet_ring_buffer *rb)
1131 {
1132         unsigned int prev;
1133         if (rb->prb_bdqc.kactive_blk_num)
1134                 prev = rb->prb_bdqc.kactive_blk_num-1;
1135         else
1136                 prev = rb->prb_bdqc.knum_blocks-1;
1137         return prev;
1138 }
1139
1140 /* Assumes caller has held the rx_queue.lock */
1141 static void *__prb_previous_block(struct packet_sock *po,
1142                                          struct packet_ring_buffer *rb,
1143                                          int status)
1144 {
1145         unsigned int previous = prb_previous_blk_num(rb);
1146         return prb_lookup_block(po, rb, previous, status);
1147 }
1148
1149 static void *packet_previous_rx_frame(struct packet_sock *po,
1150                                              struct packet_ring_buffer *rb,
1151                                              int status)
1152 {
1153         if (po->tp_version <= TPACKET_V2)
1154                 return packet_previous_frame(po, rb, status);
1155
1156         return __prb_previous_block(po, rb, status);
1157 }
1158
1159 static void packet_increment_rx_head(struct packet_sock *po,
1160                                             struct packet_ring_buffer *rb)
1161 {
1162         switch (po->tp_version) {
1163         case TPACKET_V1:
1164         case TPACKET_V2:
1165                 return packet_increment_head(rb);
1166         case TPACKET_V3:
1167         default:
1168                 WARN(1, "TPACKET version not supported.\n");
1169                 BUG();
1170                 return;
1171         }
1172 }
1173
1174 static void *packet_previous_frame(struct packet_sock *po,
1175                 struct packet_ring_buffer *rb,
1176                 int status)
1177 {
1178         unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
1179         return packet_lookup_frame(po, rb, previous, status);
1180 }
1181
1182 static void packet_increment_head(struct packet_ring_buffer *buff)
1183 {
1184         buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
1185 }
1186
1187 static void packet_inc_pending(struct packet_ring_buffer *rb)
1188 {
1189         this_cpu_inc(*rb->pending_refcnt);
1190 }
1191
1192 static void packet_dec_pending(struct packet_ring_buffer *rb)
1193 {
1194         this_cpu_dec(*rb->pending_refcnt);
1195 }
1196
1197 static unsigned int packet_read_pending(const struct packet_ring_buffer *rb)
1198 {
1199         unsigned int refcnt = 0;
1200         int cpu;
1201
1202         /* We don't use pending refcount in rx_ring. */
1203         if (rb->pending_refcnt == NULL)
1204                 return 0;
1205
1206         for_each_possible_cpu(cpu)
1207                 refcnt += *per_cpu_ptr(rb->pending_refcnt, cpu);
1208
1209         return refcnt;
1210 }
1211
1212 static int packet_alloc_pending(struct packet_sock *po)
1213 {
1214         po->rx_ring.pending_refcnt = NULL;
1215
1216         po->tx_ring.pending_refcnt = alloc_percpu(unsigned int);
1217         if (unlikely(po->tx_ring.pending_refcnt == NULL))
1218                 return -ENOBUFS;
1219
1220         return 0;
1221 }
1222
1223 static void packet_free_pending(struct packet_sock *po)
1224 {
1225         free_percpu(po->tx_ring.pending_refcnt);
1226 }
1227
1228 static bool packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1229 {
1230         struct sock *sk = &po->sk;
1231         bool has_room;
1232
1233         if (po->prot_hook.func != tpacket_rcv)
1234                 return (atomic_read(&sk->sk_rmem_alloc) + skb->truesize)
1235                         <= sk->sk_rcvbuf;
1236
1237         spin_lock(&sk->sk_receive_queue.lock);
1238         if (po->tp_version == TPACKET_V3)
1239                 has_room = prb_lookup_block(po, &po->rx_ring,
1240                                             po->rx_ring.prb_bdqc.kactive_blk_num,
1241                                             TP_STATUS_KERNEL);
1242         else
1243                 has_room = packet_lookup_frame(po, &po->rx_ring,
1244                                                po->rx_ring.head,
1245                                                TP_STATUS_KERNEL);
1246         spin_unlock(&sk->sk_receive_queue.lock);
1247
1248         return has_room;
1249 }
1250
1251 static void packet_sock_destruct(struct sock *sk)
1252 {
1253         skb_queue_purge(&sk->sk_error_queue);
1254
1255         WARN_ON(atomic_read(&sk->sk_rmem_alloc));
1256         WARN_ON(atomic_read(&sk->sk_wmem_alloc));
1257
1258         if (!sock_flag(sk, SOCK_DEAD)) {
1259                 pr_err("Attempt to release alive packet socket: %p\n", sk);
1260                 return;
1261         }
1262
1263         sk_refcnt_debug_dec(sk);
1264 }
1265
1266 static int fanout_rr_next(struct packet_fanout *f, unsigned int num)
1267 {
1268         int x = atomic_read(&f->rr_cur) + 1;
1269
1270         if (x >= num)
1271                 x = 0;
1272
1273         return x;
1274 }
1275
1276 static unsigned int fanout_demux_hash(struct packet_fanout *f,
1277                                       struct sk_buff *skb,
1278                                       unsigned int num)
1279 {
1280         return reciprocal_scale(skb->rxhash, num);
1281 }
1282
1283 static unsigned int fanout_demux_lb(struct packet_fanout *f,
1284                                     struct sk_buff *skb,
1285                                     unsigned int num)
1286 {
1287         int cur, old;
1288
1289         cur = atomic_read(&f->rr_cur);
1290         while ((old = atomic_cmpxchg(&f->rr_cur, cur,
1291                                      fanout_rr_next(f, num))) != cur)
1292                 cur = old;
1293         return cur;
1294 }
1295
1296 static unsigned int fanout_demux_cpu(struct packet_fanout *f,
1297                                      struct sk_buff *skb,
1298                                      unsigned int num)
1299 {
1300         return smp_processor_id() % num;
1301 }
1302
1303 static unsigned int fanout_demux_rnd(struct packet_fanout *f,
1304                                      struct sk_buff *skb,
1305                                      unsigned int num)
1306 {
1307         return prandom_u32_max(num);
1308 }
1309
1310 static unsigned int fanout_demux_rollover(struct packet_fanout *f,
1311                                           struct sk_buff *skb,
1312                                           unsigned int idx, unsigned int skip,
1313                                           unsigned int num)
1314 {
1315         unsigned int i, j;
1316
1317         i = j = min_t(int, f->next[idx], num - 1);
1318         do {
1319                 if (i != skip && packet_rcv_has_room(pkt_sk(f->arr[i]), skb)) {
1320                         if (i != j)
1321                                 f->next[idx] = i;
1322                         return i;
1323                 }
1324                 if (++i == num)
1325                         i = 0;
1326         } while (i != j);
1327
1328         return idx;
1329 }
1330
1331 static unsigned int fanout_demux_qm(struct packet_fanout *f,
1332                                     struct sk_buff *skb,
1333                                     unsigned int num)
1334 {
1335         return skb_get_queue_mapping(skb) % num;
1336 }
1337
1338 static bool fanout_has_flag(struct packet_fanout *f, u16 flag)
1339 {
1340         return f->flags & (flag >> 8);
1341 }
1342
1343 static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
1344                              struct packet_type *pt, struct net_device *orig_dev)
1345 {
1346         struct packet_fanout *f = pt->af_packet_priv;
1347         unsigned int num = f->num_members;
1348         struct packet_sock *po;
1349         unsigned int idx;
1350
1351         if (!net_eq(dev_net(dev), read_pnet(&f->net)) ||
1352             !num) {
1353                 kfree_skb(skb);
1354                 return 0;
1355         }
1356
1357         switch (f->type) {
1358         case PACKET_FANOUT_HASH:
1359         default:
1360                 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_DEFRAG)) {
1361                         skb = ip_check_defrag(skb, IP_DEFRAG_AF_PACKET);
1362                         if (!skb)
1363                                 return 0;
1364                 }
1365                 skb_get_hash(skb);
1366                 idx = fanout_demux_hash(f, skb, num);
1367                 break;
1368         case PACKET_FANOUT_LB:
1369                 idx = fanout_demux_lb(f, skb, num);
1370                 break;
1371         case PACKET_FANOUT_CPU:
1372                 idx = fanout_demux_cpu(f, skb, num);
1373                 break;
1374         case PACKET_FANOUT_RND:
1375                 idx = fanout_demux_rnd(f, skb, num);
1376                 break;
1377         case PACKET_FANOUT_QM:
1378                 idx = fanout_demux_qm(f, skb, num);
1379                 break;
1380         case PACKET_FANOUT_ROLLOVER:
1381                 idx = fanout_demux_rollover(f, skb, 0, (unsigned int) -1, num);
1382                 break;
1383         }
1384
1385         po = pkt_sk(f->arr[idx]);
1386         if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER) &&
1387             unlikely(!packet_rcv_has_room(po, skb))) {
1388                 idx = fanout_demux_rollover(f, skb, idx, idx, num);
1389                 po = pkt_sk(f->arr[idx]);
1390         }
1391
1392         return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
1393 }
1394
1395 DEFINE_MUTEX(fanout_mutex);
1396 EXPORT_SYMBOL_GPL(fanout_mutex);
1397 static LIST_HEAD(fanout_list);
1398
1399 static void __fanout_link(struct sock *sk, struct packet_sock *po)
1400 {
1401         struct packet_fanout *f = po->fanout;
1402
1403         spin_lock(&f->lock);
1404         f->arr[f->num_members] = sk;
1405         smp_wmb();
1406         f->num_members++;
1407         spin_unlock(&f->lock);
1408 }
1409
1410 static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
1411 {
1412         struct packet_fanout *f = po->fanout;
1413         int i;
1414
1415         spin_lock(&f->lock);
1416         for (i = 0; i < f->num_members; i++) {
1417                 if (f->arr[i] == sk)
1418                         break;
1419         }
1420         BUG_ON(i >= f->num_members);
1421         f->arr[i] = f->arr[f->num_members - 1];
1422         f->num_members--;
1423         spin_unlock(&f->lock);
1424 }
1425
1426 static bool match_fanout_group(struct packet_type *ptype, struct sock *sk)
1427 {
1428         if (ptype->af_packet_priv == (void *)((struct packet_sock *)sk)->fanout)
1429                 return true;
1430
1431         return false;
1432 }
1433
1434 static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
1435 {
1436         struct packet_sock *po = pkt_sk(sk);
1437         struct packet_fanout *f, *match;
1438         u8 type = type_flags & 0xff;
1439         u8 flags = type_flags >> 8;
1440         int err;
1441
1442         switch (type) {
1443         case PACKET_FANOUT_ROLLOVER:
1444                 if (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)
1445                         return -EINVAL;
1446         case PACKET_FANOUT_HASH:
1447         case PACKET_FANOUT_LB:
1448         case PACKET_FANOUT_CPU:
1449         case PACKET_FANOUT_RND:
1450         case PACKET_FANOUT_QM:
1451                 break;
1452         default:
1453                 return -EINVAL;
1454         }
1455
1456         if (!po->running)
1457                 return -EINVAL;
1458
1459         if (po->fanout)
1460                 return -EALREADY;
1461
1462         mutex_lock(&fanout_mutex);
1463         match = NULL;
1464         list_for_each_entry(f, &fanout_list, list) {
1465                 if (f->id == id &&
1466                     read_pnet(&f->net) == sock_net(sk)) {
1467                         match = f;
1468                         break;
1469                 }
1470         }
1471         err = -EINVAL;
1472         if (match && match->flags != flags)
1473                 goto out;
1474         if (!match) {
1475                 err = -ENOMEM;
1476                 match = kzalloc(sizeof(*match), GFP_KERNEL);
1477                 if (!match)
1478                         goto out;
1479                 write_pnet(&match->net, sock_net(sk));
1480                 match->id = id;
1481                 match->type = type;
1482                 match->flags = flags;
1483                 atomic_set(&match->rr_cur, 0);
1484                 INIT_LIST_HEAD(&match->list);
1485                 spin_lock_init(&match->lock);
1486                 atomic_set(&match->sk_ref, 0);
1487                 match->prot_hook.type = po->prot_hook.type;
1488                 match->prot_hook.dev = po->prot_hook.dev;
1489                 match->prot_hook.func = packet_rcv_fanout;
1490                 match->prot_hook.af_packet_priv = match;
1491                 match->prot_hook.id_match = match_fanout_group;
1492                 dev_add_pack(&match->prot_hook);
1493                 list_add(&match->list, &fanout_list);
1494         }
1495         err = -EINVAL;
1496         if (match->type == type &&
1497             match->prot_hook.type == po->prot_hook.type &&
1498             match->prot_hook.dev == po->prot_hook.dev) {
1499                 err = -ENOSPC;
1500                 if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) {
1501                         __dev_remove_pack(&po->prot_hook);
1502                         po->fanout = match;
1503                         atomic_inc(&match->sk_ref);
1504                         __fanout_link(sk, po);
1505                         err = 0;
1506                 }
1507         }
1508 out:
1509         mutex_unlock(&fanout_mutex);
1510         return err;
1511 }
1512
1513 static void fanout_release(struct sock *sk)
1514 {
1515         struct packet_sock *po = pkt_sk(sk);
1516         struct packet_fanout *f;
1517
1518         f = po->fanout;
1519         if (!f)
1520                 return;
1521
1522         mutex_lock(&fanout_mutex);
1523         po->fanout = NULL;
1524
1525         if (atomic_dec_and_test(&f->sk_ref)) {
1526                 list_del(&f->list);
1527                 dev_remove_pack(&f->prot_hook);
1528                 kfree(f);
1529         }
1530         mutex_unlock(&fanout_mutex);
1531 }
1532
1533 static const struct proto_ops packet_ops;
1534
1535 static const struct proto_ops packet_ops_spkt;
1536
1537 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
1538                            struct packet_type *pt, struct net_device *orig_dev)
1539 {
1540         struct sock *sk;
1541         struct sockaddr_pkt *spkt;
1542
1543         /*
1544          *      When we registered the protocol we saved the socket in the data
1545          *      field for just this event.
1546          */
1547
1548         sk = pt->af_packet_priv;
1549
1550         /*
1551          *      Yank back the headers [hope the device set this
1552          *      right or kerboom...]
1553          *
1554          *      Incoming packets have ll header pulled,
1555          *      push it back.
1556          *
1557          *      For outgoing ones skb->data == skb_mac_header(skb)
1558          *      so that this procedure is noop.
1559          */
1560
1561         if (skb->pkt_type == PACKET_LOOPBACK)
1562                 goto out;
1563
1564         if (!net_eq(dev_net(dev), sock_net(sk)))
1565                 goto out;
1566
1567         skb = skb_share_check(skb, GFP_ATOMIC);
1568         if (skb == NULL)
1569                 goto oom;
1570
1571         /* drop any routing info */
1572         skb_dst_drop(skb);
1573
1574         /* drop conntrack reference */
1575         nf_reset(skb);
1576
1577         spkt = &PACKET_SKB_CB(skb)->sa.pkt;
1578
1579         skb_push(skb, skb->data - skb_mac_header(skb));
1580
1581         /*
1582          *      The SOCK_PACKET socket receives _all_ frames.
1583          */
1584
1585         spkt->spkt_family = dev->type;
1586         strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
1587         spkt->spkt_protocol = skb->protocol;
1588
1589         /*
1590          *      Charge the memory to the socket. This is done specifically
1591          *      to prevent sockets using all the memory up.
1592          */
1593
1594         if (sock_queue_rcv_skb(sk, skb) == 0)
1595                 return 0;
1596
1597 out:
1598         kfree_skb(skb);
1599 oom:
1600         return 0;
1601 }
1602
1603
1604 /*
1605  *      Output a raw packet to a device layer. This bypasses all the other
1606  *      protocol layers and you must therefore supply it with a complete frame
1607  */
1608
1609 static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
1610                                struct msghdr *msg, size_t len)
1611 {
1612         struct sock *sk = sock->sk;
1613         DECLARE_SOCKADDR(struct sockaddr_pkt *, saddr, msg->msg_name);
1614         struct sk_buff *skb = NULL;
1615         struct net_device *dev;
1616         __be16 proto = 0;
1617         int err;
1618         int extra_len = 0;
1619
1620         /*
1621          *      Get and verify the address.
1622          */
1623
1624         if (saddr) {
1625                 if (msg->msg_namelen < sizeof(struct sockaddr))
1626                         return -EINVAL;
1627                 if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
1628                         proto = saddr->spkt_protocol;
1629         } else
1630                 return -ENOTCONN;       /* SOCK_PACKET must be sent giving an address */
1631
1632         /*
1633          *      Find the device first to size check it
1634          */
1635
1636         saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0;
1637 retry:
1638         rcu_read_lock();
1639         dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
1640         err = -ENODEV;
1641         if (dev == NULL)
1642                 goto out_unlock;
1643
1644         err = -ENETDOWN;
1645         if (!(dev->flags & IFF_UP))
1646                 goto out_unlock;
1647
1648         /*
1649          * You may not queue a frame bigger than the mtu. This is the lowest level
1650          * raw protocol and you must do your own fragmentation at this level.
1651          */
1652
1653         if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
1654                 if (!netif_supports_nofcs(dev)) {
1655                         err = -EPROTONOSUPPORT;
1656                         goto out_unlock;
1657                 }
1658                 extra_len = 4; /* We're doing our own CRC */
1659         }
1660
1661         err = -EMSGSIZE;
1662         if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len)
1663                 goto out_unlock;
1664
1665         if (!skb) {
1666                 size_t reserved = LL_RESERVED_SPACE(dev);
1667                 int tlen = dev->needed_tailroom;
1668                 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
1669
1670                 rcu_read_unlock();
1671                 skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL);
1672                 if (skb == NULL)
1673                         return -ENOBUFS;
1674                 /* FIXME: Save some space for broken drivers that write a hard
1675                  * header at transmission time by themselves. PPP is the notable
1676                  * one here. This should really be fixed at the driver level.
1677                  */
1678                 skb_reserve(skb, reserved);
1679                 skb_reset_network_header(skb);
1680
1681                 /* Try to align data part correctly */
1682                 if (hhlen) {
1683                         skb->data -= hhlen;
1684                         skb->tail -= hhlen;
1685                         if (len < hhlen)
1686                                 skb_reset_network_header(skb);
1687                 }
1688                 err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
1689                 if (err)
1690                         goto out_free;
1691                 goto retry;
1692         }
1693
1694         if (len > (dev->mtu + dev->hard_header_len + extra_len)) {
1695                 /* Earlier code assumed this would be a VLAN pkt,
1696                  * double-check this now that we have the actual
1697                  * packet in hand.
1698                  */
1699                 struct ethhdr *ehdr;
1700                 skb_reset_mac_header(skb);
1701                 ehdr = eth_hdr(skb);
1702                 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
1703                         err = -EMSGSIZE;
1704                         goto out_unlock;
1705                 }
1706         }
1707
1708         skb->protocol = proto;
1709         skb->dev = dev;
1710         skb->priority = sk->sk_priority;
1711         skb->mark = sk->sk_mark;
1712
1713         sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
1714
1715         if (unlikely(extra_len == 4))
1716                 skb->no_fcs = 1;
1717
1718         skb_probe_transport_header(skb, 0);
1719
1720         dev_queue_xmit(skb);
1721         rcu_read_unlock();
1722         return len;
1723
1724 out_unlock:
1725         rcu_read_unlock();
1726 out_free:
1727         kfree_skb(skb);
1728         return err;
1729 }
1730
1731 static unsigned int run_filter(const struct sk_buff *skb,
1732                                       const struct sock *sk,
1733                                       unsigned int res)
1734 {
1735         struct sk_filter *filter;
1736
1737         rcu_read_lock();
1738         filter = rcu_dereference(sk->sk_filter);
1739         if (filter != NULL)
1740                 res = SK_RUN_FILTER(filter, skb);
1741         rcu_read_unlock();
1742
1743         return res;
1744 }
1745
1746 /*
1747  * This function makes lazy skb cloning in hope that most of packets
1748  * are discarded by BPF.
1749  *
1750  * Note tricky part: we DO mangle shared skb! skb->data, skb->len
1751  * and skb->cb are mangled. It works because (and until) packets
1752  * falling here are owned by current CPU. Output packets are cloned
1753  * by dev_queue_xmit_nit(), input packets are processed by net_bh
1754  * sequencially, so that if we return skb to original state on exit,
1755  * we will not harm anyone.
1756  */
1757
1758 static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
1759                       struct packet_type *pt, struct net_device *orig_dev)
1760 {
1761         struct sock *sk;
1762         struct sockaddr_ll *sll;
1763         struct packet_sock *po;
1764         u8 *skb_head = skb->data;
1765         int skb_len = skb->len;
1766         unsigned int snaplen, res;
1767
1768         if (skb->pkt_type == PACKET_LOOPBACK)
1769                 goto drop;
1770
1771         sk = pt->af_packet_priv;
1772         po = pkt_sk(sk);
1773
1774         if (!net_eq(dev_net(dev), sock_net(sk)))
1775                 goto drop;
1776
1777         skb->dev = dev;
1778
1779         if (dev->header_ops) {
1780                 /* The device has an explicit notion of ll header,
1781                  * exported to higher levels.
1782                  *
1783                  * Otherwise, the device hides details of its frame
1784                  * structure, so that corresponding packet head is
1785                  * never delivered to user.
1786                  */
1787                 if (sk->sk_type != SOCK_DGRAM)
1788                         skb_push(skb, skb->data - skb_mac_header(skb));
1789                 else if (skb->pkt_type == PACKET_OUTGOING) {
1790                         /* Special case: outgoing packets have ll header at head */
1791                         skb_pull(skb, skb_network_offset(skb));
1792                 }
1793         }
1794
1795         snaplen = skb->len;
1796
1797         res = run_filter(skb, sk, snaplen);
1798         if (!res)
1799                 goto drop_n_restore;
1800         if (snaplen > res)
1801                 snaplen = res;
1802
1803         if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
1804                 goto drop_n_acct;
1805
1806         if (skb_shared(skb)) {
1807                 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
1808                 if (nskb == NULL)
1809                         goto drop_n_acct;
1810
1811                 if (skb_head != skb->data) {
1812                         skb->data = skb_head;
1813                         skb->len = skb_len;
1814                 }
1815                 consume_skb(skb);
1816                 skb = nskb;
1817         }
1818
1819         BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 >
1820                      sizeof(skb->cb));
1821
1822         sll = &PACKET_SKB_CB(skb)->sa.ll;
1823         sll->sll_family = AF_PACKET;
1824         sll->sll_hatype = dev->type;
1825         sll->sll_protocol = skb->protocol;
1826         sll->sll_pkttype = skb->pkt_type;
1827         if (unlikely(po->origdev))
1828                 sll->sll_ifindex = orig_dev->ifindex;
1829         else
1830                 sll->sll_ifindex = dev->ifindex;
1831
1832         sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
1833
1834         PACKET_SKB_CB(skb)->origlen = skb->len;
1835
1836         if (pskb_trim(skb, snaplen))
1837                 goto drop_n_acct;
1838
1839         skb_set_owner_r(skb, sk);
1840         skb->dev = NULL;
1841         skb_dst_drop(skb);
1842
1843         /* drop conntrack reference */
1844         nf_reset(skb);
1845
1846         spin_lock(&sk->sk_receive_queue.lock);
1847         po->stats.stats1.tp_packets++;
1848         skb->dropcount = atomic_read(&sk->sk_drops);
1849         __skb_queue_tail(&sk->sk_receive_queue, skb);
1850         spin_unlock(&sk->sk_receive_queue.lock);
1851         sk->sk_data_ready(sk, skb->len);
1852         return 0;
1853
1854 drop_n_acct:
1855         spin_lock(&sk->sk_receive_queue.lock);
1856         po->stats.stats1.tp_drops++;
1857         atomic_inc(&sk->sk_drops);
1858         spin_unlock(&sk->sk_receive_queue.lock);
1859
1860 drop_n_restore:
1861         if (skb_head != skb->data && skb_shared(skb)) {
1862                 skb->data = skb_head;
1863                 skb->len = skb_len;
1864         }
1865 drop:
1866         consume_skb(skb);
1867         return 0;
1868 }
1869
1870 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
1871                        struct packet_type *pt, struct net_device *orig_dev)
1872 {
1873         struct sock *sk;
1874         struct packet_sock *po;
1875         struct sockaddr_ll *sll;
1876         union tpacket_uhdr h;
1877         u8 *skb_head = skb->data;
1878         int skb_len = skb->len;
1879         unsigned int snaplen, res;
1880         unsigned long status = TP_STATUS_USER;
1881         unsigned short macoff, netoff, hdrlen;
1882         struct sk_buff *copy_skb = NULL;
1883         struct timespec ts;
1884         __u32 ts_status;
1885
1886         /* struct tpacket{2,3}_hdr is aligned to a multiple of TPACKET_ALIGNMENT.
1887          * We may add members to them until current aligned size without forcing
1888          * userspace to call getsockopt(..., PACKET_HDRLEN, ...).
1889          */
1890         BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h2)) != 32);
1891         BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h3)) != 48);
1892
1893         if (skb->pkt_type == PACKET_LOOPBACK)
1894                 goto drop;
1895
1896         sk = pt->af_packet_priv;
1897         po = pkt_sk(sk);
1898
1899         if (!net_eq(dev_net(dev), sock_net(sk)))
1900                 goto drop;
1901
1902         if (dev->header_ops) {
1903                 if (sk->sk_type != SOCK_DGRAM)
1904                         skb_push(skb, skb->data - skb_mac_header(skb));
1905                 else if (skb->pkt_type == PACKET_OUTGOING) {
1906                         /* Special case: outgoing packets have ll header at head */
1907                         skb_pull(skb, skb_network_offset(skb));
1908                 }
1909         }
1910
1911         if (skb->ip_summed == CHECKSUM_PARTIAL)
1912                 status |= TP_STATUS_CSUMNOTREADY;
1913
1914         snaplen = skb->len;
1915
1916         res = run_filter(skb, sk, snaplen);
1917         if (!res)
1918                 goto drop_n_restore;
1919         if (snaplen > res)
1920                 snaplen = res;
1921
1922         if (sk->sk_type == SOCK_DGRAM) {
1923                 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
1924                                   po->tp_reserve;
1925         } else {
1926                 unsigned int maclen = skb_network_offset(skb);
1927                 netoff = TPACKET_ALIGN(po->tp_hdrlen +
1928                                        (maclen < 16 ? 16 : maclen)) +
1929                         po->tp_reserve;
1930                 macoff = netoff - maclen;
1931         }
1932         if (po->tp_version <= TPACKET_V2) {
1933                 if (macoff + snaplen > po->rx_ring.frame_size) {
1934                         if (po->copy_thresh &&
1935                             atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1936                                 if (skb_shared(skb)) {
1937                                         copy_skb = skb_clone(skb, GFP_ATOMIC);
1938                                 } else {
1939                                         copy_skb = skb_get(skb);
1940                                         skb_head = skb->data;
1941                                 }
1942                                 if (copy_skb)
1943                                         skb_set_owner_r(copy_skb, sk);
1944                         }
1945                         snaplen = po->rx_ring.frame_size - macoff;
1946                         if ((int)snaplen < 0)
1947                                 snaplen = 0;
1948                 }
1949         }
1950         spin_lock(&sk->sk_receive_queue.lock);
1951         h.raw = packet_current_rx_frame(po, skb,
1952                                         TP_STATUS_KERNEL, (macoff+snaplen));
1953         if (!h.raw)
1954                 goto ring_is_full;
1955         if (po->tp_version <= TPACKET_V2) {
1956                 packet_increment_rx_head(po, &po->rx_ring);
1957         /*
1958          * LOSING will be reported till you read the stats,
1959          * because it's COR - Clear On Read.
1960          * Anyways, moving it for V1/V2 only as V3 doesn't need this
1961          * at packet level.
1962          */
1963                 if (po->stats.stats1.tp_drops)
1964                         status |= TP_STATUS_LOSING;
1965         }
1966         po->stats.stats1.tp_packets++;
1967         if (copy_skb) {
1968                 status |= TP_STATUS_COPY;
1969                 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
1970         }
1971         spin_unlock(&sk->sk_receive_queue.lock);
1972
1973         skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
1974
1975         if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
1976                 getnstimeofday(&ts);
1977
1978         status |= ts_status;
1979
1980         switch (po->tp_version) {
1981         case TPACKET_V1:
1982                 h.h1->tp_len = skb->len;
1983                 h.h1->tp_snaplen = snaplen;
1984                 h.h1->tp_mac = macoff;
1985                 h.h1->tp_net = netoff;
1986                 h.h1->tp_sec = ts.tv_sec;
1987                 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
1988                 hdrlen = sizeof(*h.h1);
1989                 break;
1990         case TPACKET_V2:
1991                 h.h2->tp_len = skb->len;
1992                 h.h2->tp_snaplen = snaplen;
1993                 h.h2->tp_mac = macoff;
1994                 h.h2->tp_net = netoff;
1995                 h.h2->tp_sec = ts.tv_sec;
1996                 h.h2->tp_nsec = ts.tv_nsec;
1997                 if (vlan_tx_tag_present(skb)) {
1998                         h.h2->tp_vlan_tci = vlan_tx_tag_get(skb);
1999                         h.h2->tp_vlan_tpid = ntohs(skb->vlan_proto);
2000                         status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
2001                 } else {
2002                         h.h2->tp_vlan_tci = 0;
2003                         h.h2->tp_vlan_tpid = 0;
2004                 }
2005                 memset(h.h2->tp_padding, 0, sizeof(h.h2->tp_padding));
2006                 hdrlen = sizeof(*h.h2);
2007                 break;
2008         case TPACKET_V3:
2009                 /* tp_nxt_offset,vlan are already populated above.
2010                  * So DONT clear those fields here
2011                  */
2012                 h.h3->tp_status |= status;
2013                 h.h3->tp_len = skb->len;
2014                 h.h3->tp_snaplen = snaplen;
2015                 h.h3->tp_mac = macoff;
2016                 h.h3->tp_net = netoff;
2017                 h.h3->tp_sec  = ts.tv_sec;
2018                 h.h3->tp_nsec = ts.tv_nsec;
2019                 memset(h.h3->tp_padding, 0, sizeof(h.h3->tp_padding));
2020                 hdrlen = sizeof(*h.h3);
2021                 break;
2022         default:
2023                 BUG();
2024         }
2025
2026         sll = h.raw + TPACKET_ALIGN(hdrlen);
2027         sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
2028         sll->sll_family = AF_PACKET;
2029         sll->sll_hatype = dev->type;
2030         sll->sll_protocol = skb->protocol;
2031         sll->sll_pkttype = skb->pkt_type;
2032         if (unlikely(po->origdev))
2033                 sll->sll_ifindex = orig_dev->ifindex;
2034         else
2035                 sll->sll_ifindex = dev->ifindex;
2036
2037         smp_mb();
2038
2039 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
2040         if (po->tp_version <= TPACKET_V2) {
2041                 u8 *start, *end;
2042
2043                 end = (u8 *) PAGE_ALIGN((unsigned long) h.raw +
2044                                         macoff + snaplen);
2045
2046                 for (start = h.raw; start < end; start += PAGE_SIZE)
2047                         flush_dcache_page(pgv_to_page(start));
2048         }
2049         smp_wmb();
2050 #endif
2051
2052         if (po->tp_version <= TPACKET_V2)
2053                 __packet_set_status(po, h.raw, status);
2054         else
2055                 prb_clear_blk_fill_status(&po->rx_ring);
2056
2057         sk->sk_data_ready(sk, 0);
2058
2059 drop_n_restore:
2060         if (skb_head != skb->data && skb_shared(skb)) {
2061                 skb->data = skb_head;
2062                 skb->len = skb_len;
2063         }
2064 drop:
2065         kfree_skb(skb);
2066         return 0;
2067
2068 ring_is_full:
2069         po->stats.stats1.tp_drops++;
2070         spin_unlock(&sk->sk_receive_queue.lock);
2071
2072         sk->sk_data_ready(sk, 0);
2073         kfree_skb(copy_skb);
2074         goto drop_n_restore;
2075 }
2076
2077 static void tpacket_destruct_skb(struct sk_buff *skb)
2078 {
2079         struct packet_sock *po = pkt_sk(skb->sk);
2080
2081         if (likely(po->tx_ring.pg_vec)) {
2082                 void *ph;
2083                 __u32 ts;
2084
2085                 ph = skb_shinfo(skb)->destructor_arg;
2086                 packet_dec_pending(&po->tx_ring);
2087
2088                 ts = __packet_set_timestamp(po, ph, skb);
2089                 __packet_set_status(po, ph, TP_STATUS_AVAILABLE | ts);
2090         }
2091
2092         sock_wfree(skb);
2093 }
2094
2095 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
2096                 void *frame, struct net_device *dev, int size_max,
2097                 __be16 proto, unsigned char *addr, int hlen)
2098 {
2099         union tpacket_uhdr ph;
2100         int to_write, offset, len, tp_len, nr_frags, len_max;
2101         struct socket *sock = po->sk.sk_socket;
2102         struct page *page;
2103         void *data;
2104         int err;
2105
2106         ph.raw = frame;
2107
2108         skb->protocol = proto;
2109         skb->dev = dev;
2110         skb->priority = po->sk.sk_priority;
2111         skb->mark = po->sk.sk_mark;
2112         sock_tx_timestamp(&po->sk, &skb_shinfo(skb)->tx_flags);
2113         skb_shinfo(skb)->destructor_arg = ph.raw;
2114
2115         switch (po->tp_version) {
2116         case TPACKET_V2:
2117                 tp_len = ph.h2->tp_len;
2118                 break;
2119         default:
2120                 tp_len = ph.h1->tp_len;
2121                 break;
2122         }
2123         if (unlikely(tp_len > size_max)) {
2124                 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
2125                 return -EMSGSIZE;
2126         }
2127
2128         skb_reserve(skb, hlen);
2129         skb_reset_network_header(skb);
2130
2131         if (!packet_use_direct_xmit(po))
2132                 skb_probe_transport_header(skb, 0);
2133         if (unlikely(po->tp_tx_has_off)) {
2134                 int off_min, off_max, off;
2135                 off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll);
2136                 off_max = po->tx_ring.frame_size - tp_len;
2137                 if (sock->type == SOCK_DGRAM) {
2138                         switch (po->tp_version) {
2139                         case TPACKET_V2:
2140                                 off = ph.h2->tp_net;
2141                                 break;
2142                         default:
2143                                 off = ph.h1->tp_net;
2144                                 break;
2145                         }
2146                 } else {
2147                         switch (po->tp_version) {
2148                         case TPACKET_V2:
2149                                 off = ph.h2->tp_mac;
2150                                 break;
2151                         default:
2152                                 off = ph.h1->tp_mac;
2153                                 break;
2154                         }
2155                 }
2156                 if (unlikely((off < off_min) || (off_max < off)))
2157                         return -EINVAL;
2158                 data = ph.raw + off;
2159         } else {
2160                 data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll);
2161         }
2162         to_write = tp_len;
2163
2164         if (sock->type == SOCK_DGRAM) {
2165                 err = dev_hard_header(skb, dev, ntohs(proto), addr,
2166                                 NULL, tp_len);
2167                 if (unlikely(err < 0))
2168                         return -EINVAL;
2169         } else if (dev->hard_header_len) {
2170                 /* net device doesn't like empty head */
2171                 if (unlikely(tp_len <= dev->hard_header_len)) {
2172                         pr_err("packet size is too short (%d < %d)\n",
2173                                tp_len, dev->hard_header_len);
2174                         return -EINVAL;
2175                 }
2176
2177                 skb_push(skb, dev->hard_header_len);
2178                 err = skb_store_bits(skb, 0, data,
2179                                 dev->hard_header_len);
2180                 if (unlikely(err))
2181                         return err;
2182
2183                 data += dev->hard_header_len;
2184                 to_write -= dev->hard_header_len;
2185         }
2186
2187         offset = offset_in_page(data);
2188         len_max = PAGE_SIZE - offset;
2189         len = ((to_write > len_max) ? len_max : to_write);
2190
2191         skb->data_len = to_write;
2192         skb->len += to_write;
2193         skb->truesize += to_write;
2194         atomic_add(to_write, &po->sk.sk_wmem_alloc);
2195
2196         while (likely(to_write)) {
2197                 nr_frags = skb_shinfo(skb)->nr_frags;
2198
2199                 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
2200                         pr_err("Packet exceed the number of skb frags(%lu)\n",
2201                                MAX_SKB_FRAGS);
2202                         return -EFAULT;
2203                 }
2204
2205                 page = pgv_to_page(data);
2206                 data += len;
2207                 flush_dcache_page(page);
2208                 get_page(page);
2209                 skb_fill_page_desc(skb, nr_frags, page, offset, len);
2210                 to_write -= len;
2211                 offset = 0;
2212                 len_max = PAGE_SIZE;
2213                 len = ((to_write > len_max) ? len_max : to_write);
2214         }
2215
2216         return tp_len;
2217 }
2218
2219 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
2220 {
2221         struct sk_buff *skb;
2222         struct net_device *dev;
2223         __be16 proto;
2224         int err, reserve = 0;
2225         void *ph;
2226         DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2227         bool need_wait = !(msg->msg_flags & MSG_DONTWAIT);
2228         int tp_len, size_max;
2229         unsigned char *addr;
2230         int len_sum = 0;
2231         int status = TP_STATUS_AVAILABLE;
2232         int hlen, tlen;
2233
2234         mutex_lock(&po->pg_vec_lock);
2235
2236         if (likely(saddr == NULL)) {
2237                 dev     = packet_cached_dev_get(po);
2238                 proto   = po->num;
2239                 addr    = NULL;
2240         } else {
2241                 err = -EINVAL;
2242                 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2243                         goto out;
2244                 if (msg->msg_namelen < (saddr->sll_halen
2245                                         + offsetof(struct sockaddr_ll,
2246                                                 sll_addr)))
2247                         goto out;
2248                 proto   = saddr->sll_protocol;
2249                 addr    = saddr->sll_addr;
2250                 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
2251         }
2252
2253         err = -ENXIO;
2254         if (unlikely(dev == NULL))
2255                 goto out;
2256         err = -ENETDOWN;
2257         if (unlikely(!(dev->flags & IFF_UP)))
2258                 goto out_put;
2259
2260         reserve = dev->hard_header_len;
2261
2262         size_max = po->tx_ring.frame_size
2263                 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
2264
2265         if (size_max > dev->mtu + reserve)
2266                 size_max = dev->mtu + reserve;
2267
2268         do {
2269                 ph = packet_current_frame(po, &po->tx_ring,
2270                                           TP_STATUS_SEND_REQUEST);
2271                 if (unlikely(ph == NULL)) {
2272                         if (need_wait && need_resched())
2273                                 schedule();
2274                         continue;
2275                 }
2276
2277                 status = TP_STATUS_SEND_REQUEST;
2278                 hlen = LL_RESERVED_SPACE(dev);
2279                 tlen = dev->needed_tailroom;
2280                 skb = sock_alloc_send_skb(&po->sk,
2281                                 hlen + tlen + sizeof(struct sockaddr_ll),
2282                                 0, &err);
2283
2284                 if (unlikely(skb == NULL))
2285                         goto out_status;
2286
2287                 tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
2288                                 addr, hlen);
2289
2290                 if (unlikely(tp_len < 0)) {
2291                         if (po->tp_loss) {
2292                                 __packet_set_status(po, ph,
2293                                                 TP_STATUS_AVAILABLE);
2294                                 packet_increment_head(&po->tx_ring);
2295                                 kfree_skb(skb);
2296                                 continue;
2297                         } else {
2298                                 status = TP_STATUS_WRONG_FORMAT;
2299                                 err = tp_len;
2300                                 goto out_status;
2301                         }
2302                 }
2303
2304                 packet_pick_tx_queue(dev, skb);
2305
2306                 skb->destructor = tpacket_destruct_skb;
2307                 __packet_set_status(po, ph, TP_STATUS_SENDING);
2308                 packet_inc_pending(&po->tx_ring);
2309
2310                 status = TP_STATUS_SEND_REQUEST;
2311                 err = po->xmit(skb);
2312                 if (unlikely(err > 0)) {
2313                         err = net_xmit_errno(err);
2314                         if (err && __packet_get_status(po, ph) ==
2315                                    TP_STATUS_AVAILABLE) {
2316                                 /* skb was destructed already */
2317                                 skb = NULL;
2318                                 goto out_status;
2319                         }
2320                         /*
2321                          * skb was dropped but not destructed yet;
2322                          * let's treat it like congestion or err < 0
2323                          */
2324                         err = 0;
2325                 }
2326                 packet_increment_head(&po->tx_ring);
2327                 len_sum += tp_len;
2328         } while (likely((ph != NULL) ||
2329                 /* Note: packet_read_pending() might be slow if we have
2330                  * to call it as it's per_cpu variable, but in fast-path
2331                  * we already short-circuit the loop with the first
2332                  * condition, and luckily don't have to go that path
2333                  * anyway.
2334                  */
2335                  (need_wait && packet_read_pending(&po->tx_ring))));
2336
2337         err = len_sum;
2338         goto out_put;
2339
2340 out_status:
2341         __packet_set_status(po, ph, status);
2342         kfree_skb(skb);
2343 out_put:
2344         dev_put(dev);
2345 out:
2346         mutex_unlock(&po->pg_vec_lock);
2347         return err;
2348 }
2349
2350 static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
2351                                         size_t reserve, size_t len,
2352                                         size_t linear, int noblock,
2353                                         int *err)
2354 {
2355         struct sk_buff *skb;
2356
2357         /* Under a page?  Don't bother with paged skb. */
2358         if (prepad + len < PAGE_SIZE || !linear)
2359                 linear = len;
2360
2361         skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
2362                                    err, 0);
2363         if (!skb)
2364                 return NULL;
2365
2366         skb_reserve(skb, reserve);
2367         skb_put(skb, linear);
2368         skb->data_len = len - linear;
2369         skb->len += len - linear;
2370
2371         return skb;
2372 }
2373
2374 static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
2375 {
2376         struct sock *sk = sock->sk;
2377         DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2378         struct sk_buff *skb;
2379         struct net_device *dev;
2380         __be16 proto;
2381         unsigned char *addr;
2382         int err, reserve = 0;
2383         struct virtio_net_hdr vnet_hdr = { 0 };
2384         int offset = 0;
2385         int vnet_hdr_len;
2386         struct packet_sock *po = pkt_sk(sk);
2387         unsigned short gso_type = 0;
2388         int hlen, tlen;
2389         int extra_len = 0;
2390
2391         /*
2392          *      Get and verify the address.
2393          */
2394
2395         if (likely(saddr == NULL)) {
2396                 dev     = packet_cached_dev_get(po);
2397                 proto   = po->num;
2398                 addr    = NULL;
2399         } else {
2400                 err = -EINVAL;
2401                 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2402                         goto out;
2403                 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
2404                         goto out;
2405                 proto   = saddr->sll_protocol;
2406                 addr    = saddr->sll_addr;
2407                 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
2408         }
2409
2410         err = -ENXIO;
2411         if (unlikely(dev == NULL))
2412                 goto out_unlock;
2413         err = -ENETDOWN;
2414         if (unlikely(!(dev->flags & IFF_UP)))
2415                 goto out_unlock;
2416
2417         if (sock->type == SOCK_RAW)
2418                 reserve = dev->hard_header_len;
2419         if (po->has_vnet_hdr) {
2420                 vnet_hdr_len = sizeof(vnet_hdr);
2421
2422                 err = -EINVAL;
2423                 if (len < vnet_hdr_len)
2424                         goto out_unlock;
2425
2426                 len -= vnet_hdr_len;
2427
2428                 err = memcpy_fromiovec((void *)&vnet_hdr, msg->msg_iov,
2429                                        vnet_hdr_len);
2430                 if (err < 0)
2431                         goto out_unlock;
2432
2433                 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
2434                     (vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 >
2435                       vnet_hdr.hdr_len))
2436                         vnet_hdr.hdr_len = vnet_hdr.csum_start +
2437                                                  vnet_hdr.csum_offset + 2;
2438
2439                 err = -EINVAL;
2440                 if (vnet_hdr.hdr_len > len)
2441                         goto out_unlock;
2442
2443                 if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
2444                         switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
2445                         case VIRTIO_NET_HDR_GSO_TCPV4:
2446                                 gso_type = SKB_GSO_TCPV4;
2447                                 break;
2448                         case VIRTIO_NET_HDR_GSO_TCPV6:
2449                                 gso_type = SKB_GSO_TCPV6;
2450                                 break;
2451                         case VIRTIO_NET_HDR_GSO_UDP:
2452                                 gso_type = SKB_GSO_UDP;
2453                                 break;
2454                         default:
2455                                 goto out_unlock;
2456                         }
2457
2458                         if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
2459                                 gso_type |= SKB_GSO_TCP_ECN;
2460
2461                         if (vnet_hdr.gso_size == 0)
2462                                 goto out_unlock;
2463
2464                 }
2465         }
2466
2467         if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
2468                 if (!netif_supports_nofcs(dev)) {
2469                         err = -EPROTONOSUPPORT;
2470                         goto out_unlock;
2471                 }
2472                 extra_len = 4; /* We're doing our own CRC */
2473         }
2474
2475         err = -EMSGSIZE;
2476         if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN + extra_len))
2477                 goto out_unlock;
2478
2479         err = -ENOBUFS;
2480         hlen = LL_RESERVED_SPACE(dev);
2481         tlen = dev->needed_tailroom;
2482         skb = packet_alloc_skb(sk, hlen + tlen, hlen, len, vnet_hdr.hdr_len,
2483                                msg->msg_flags & MSG_DONTWAIT, &err);
2484         if (skb == NULL)
2485                 goto out_unlock;
2486
2487         skb_set_network_header(skb, reserve);
2488
2489         err = -EINVAL;
2490         if (sock->type == SOCK_DGRAM &&
2491             (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0)
2492                 goto out_free;
2493
2494         /* Returns -EFAULT on error */
2495         err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len);
2496         if (err)
2497                 goto out_free;
2498
2499         sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
2500
2501         if (!gso_type && (len > dev->mtu + reserve + extra_len)) {
2502                 /* Earlier code assumed this would be a VLAN pkt,
2503                  * double-check this now that we have the actual
2504                  * packet in hand.
2505                  */
2506                 struct ethhdr *ehdr;
2507                 skb_reset_mac_header(skb);
2508                 ehdr = eth_hdr(skb);
2509                 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
2510                         err = -EMSGSIZE;
2511                         goto out_free;
2512                 }
2513         }
2514
2515         skb->protocol = proto;
2516         skb->dev = dev;
2517         skb->priority = sk->sk_priority;
2518         skb->mark = sk->sk_mark;
2519
2520         packet_pick_tx_queue(dev, skb);
2521
2522         if (po->has_vnet_hdr) {
2523                 if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
2524                         if (!skb_partial_csum_set(skb, vnet_hdr.csum_start,
2525                                                   vnet_hdr.csum_offset)) {
2526                                 err = -EINVAL;
2527                                 goto out_free;
2528                         }
2529                 }
2530
2531                 skb_shinfo(skb)->gso_size = vnet_hdr.gso_size;
2532                 skb_shinfo(skb)->gso_type = gso_type;
2533
2534                 /* Header must be checked, and gso_segs computed. */
2535                 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2536                 skb_shinfo(skb)->gso_segs = 0;
2537
2538                 len += vnet_hdr_len;
2539         }
2540
2541         if (!packet_use_direct_xmit(po))
2542                 skb_probe_transport_header(skb, reserve);
2543         if (unlikely(extra_len == 4))
2544                 skb->no_fcs = 1;
2545
2546         err = po->xmit(skb);
2547         if (err > 0 && (err = net_xmit_errno(err)) != 0)
2548                 goto out_unlock;
2549
2550         dev_put(dev);
2551
2552         return len;
2553
2554 out_free:
2555         kfree_skb(skb);
2556 out_unlock:
2557         if (dev)
2558                 dev_put(dev);
2559 out:
2560         return err;
2561 }
2562
2563 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
2564                 struct msghdr *msg, size_t len)
2565 {
2566         struct sock *sk = sock->sk;
2567         struct packet_sock *po = pkt_sk(sk);
2568
2569         if (po->tx_ring.pg_vec)
2570                 return tpacket_snd(po, msg);
2571         else
2572                 return packet_snd(sock, msg, len);
2573 }
2574
2575 /*
2576  *      Close a PACKET socket. This is fairly simple. We immediately go
2577  *      to 'closed' state and remove our protocol entry in the device list.
2578  */
2579
2580 static int packet_release(struct socket *sock)
2581 {
2582         struct sock *sk = sock->sk;
2583         struct packet_sock *po;
2584         struct net *net;
2585         union tpacket_req_u req_u;
2586
2587         if (!sk)
2588                 return 0;
2589
2590         net = sock_net(sk);
2591         po = pkt_sk(sk);
2592
2593         mutex_lock(&net->packet.sklist_lock);
2594         sk_del_node_init_rcu(sk);
2595         mutex_unlock(&net->packet.sklist_lock);
2596
2597         preempt_disable();
2598         sock_prot_inuse_add(net, sk->sk_prot, -1);
2599         preempt_enable();
2600
2601         spin_lock(&po->bind_lock);
2602         unregister_prot_hook(sk, false);
2603         packet_cached_dev_reset(po);
2604
2605         if (po->prot_hook.dev) {
2606                 dev_put(po->prot_hook.dev);
2607                 po->prot_hook.dev = NULL;
2608         }
2609         spin_unlock(&po->bind_lock);
2610
2611         packet_flush_mclist(sk);
2612
2613         if (po->rx_ring.pg_vec) {
2614                 memset(&req_u, 0, sizeof(req_u));
2615                 packet_set_ring(sk, &req_u, 1, 0);
2616         }
2617
2618         if (po->tx_ring.pg_vec) {
2619                 memset(&req_u, 0, sizeof(req_u));
2620                 packet_set_ring(sk, &req_u, 1, 1);
2621         }
2622
2623         fanout_release(sk);
2624
2625         synchronize_net();
2626         /*
2627          *      Now the socket is dead. No more input will appear.
2628          */
2629         sock_orphan(sk);
2630         sock->sk = NULL;
2631
2632         /* Purge queues */
2633
2634         skb_queue_purge(&sk->sk_receive_queue);
2635         packet_free_pending(po);
2636         sk_refcnt_debug_release(sk);
2637
2638         sock_put(sk);
2639         return 0;
2640 }
2641
2642 /*
2643  *      Attach a packet hook.
2644  */
2645
2646 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 proto)
2647 {
2648         struct packet_sock *po = pkt_sk(sk);
2649         const struct net_device *dev_curr;
2650         __be16 proto_curr;
2651         bool need_rehook;
2652
2653         if (po->fanout) {
2654                 if (dev)
2655                         dev_put(dev);
2656
2657                 return -EINVAL;
2658         }
2659
2660         lock_sock(sk);
2661         spin_lock(&po->bind_lock);
2662
2663         proto_curr = po->prot_hook.type;
2664         dev_curr = po->prot_hook.dev;
2665
2666         need_rehook = proto_curr != proto || dev_curr != dev;
2667
2668         if (need_rehook) {
2669                 unregister_prot_hook(sk, true);
2670
2671                 po->num = proto;
2672                 po->prot_hook.type = proto;
2673
2674                 if (po->prot_hook.dev)
2675                         dev_put(po->prot_hook.dev);
2676
2677                 po->prot_hook.dev = dev;
2678
2679                 po->ifindex = dev ? dev->ifindex : 0;
2680                 packet_cached_dev_assign(po, dev);
2681         }
2682
2683         if (proto == 0 || !need_rehook)
2684                 goto out_unlock;
2685
2686         if (!dev || (dev->flags & IFF_UP)) {
2687                 register_prot_hook(sk);
2688         } else {
2689                 sk->sk_err = ENETDOWN;
2690                 if (!sock_flag(sk, SOCK_DEAD))
2691                         sk->sk_error_report(sk);
2692         }
2693
2694 out_unlock:
2695         spin_unlock(&po->bind_lock);
2696         release_sock(sk);
2697         return 0;
2698 }
2699
2700 /*
2701  *      Bind a packet socket to a device
2702  */
2703
2704 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
2705                             int addr_len)
2706 {
2707         struct sock *sk = sock->sk;
2708         char name[15];
2709         struct net_device *dev;
2710         int err = -ENODEV;
2711
2712         /*
2713          *      Check legality
2714          */
2715
2716         if (addr_len != sizeof(struct sockaddr))
2717                 return -EINVAL;
2718         strlcpy(name, uaddr->sa_data, sizeof(name));
2719
2720         dev = dev_get_by_name(sock_net(sk), name);
2721         if (dev)
2722                 err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
2723         return err;
2724 }
2725
2726 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
2727 {
2728         struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
2729         struct sock *sk = sock->sk;
2730         struct net_device *dev = NULL;
2731         int err;
2732
2733
2734         /*
2735          *      Check legality
2736          */
2737
2738         if (addr_len < sizeof(struct sockaddr_ll))
2739                 return -EINVAL;
2740         if (sll->sll_family != AF_PACKET)
2741                 return -EINVAL;
2742
2743         if (sll->sll_ifindex) {
2744                 err = -ENODEV;
2745                 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
2746                 if (dev == NULL)
2747                         goto out;
2748         }
2749         err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
2750
2751 out:
2752         return err;
2753 }
2754
2755 static struct proto packet_proto = {
2756         .name     = "PACKET",
2757         .owner    = THIS_MODULE,
2758         .obj_size = sizeof(struct packet_sock),
2759 };
2760
2761 /*
2762  *      Create a packet of type SOCK_PACKET.
2763  */
2764
2765 static int packet_create(struct net *net, struct socket *sock, int protocol,
2766                          int kern)
2767 {
2768         struct sock *sk;
2769         struct packet_sock *po;
2770         __be16 proto = (__force __be16)protocol; /* weird, but documented */
2771         int err;
2772
2773         if (!ns_capable(net->user_ns, CAP_NET_RAW))
2774                 return -EPERM;
2775         if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
2776             sock->type != SOCK_PACKET)
2777                 return -ESOCKTNOSUPPORT;
2778
2779         sock->state = SS_UNCONNECTED;
2780
2781         err = -ENOBUFS;
2782         sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
2783         if (sk == NULL)
2784                 goto out;
2785
2786         sock->ops = &packet_ops;
2787         if (sock->type == SOCK_PACKET)
2788                 sock->ops = &packet_ops_spkt;
2789
2790         sock_init_data(sock, sk);
2791
2792         po = pkt_sk(sk);
2793         sk->sk_family = PF_PACKET;
2794         po->num = proto;
2795         po->xmit = dev_queue_xmit;
2796
2797         err = packet_alloc_pending(po);
2798         if (err)
2799                 goto out2;
2800
2801         packet_cached_dev_reset(po);
2802
2803         sk->sk_destruct = packet_sock_destruct;
2804         sk_refcnt_debug_inc(sk);
2805
2806         /*
2807          *      Attach a protocol block
2808          */
2809
2810         spin_lock_init(&po->bind_lock);
2811         mutex_init(&po->pg_vec_lock);
2812         po->prot_hook.func = packet_rcv;
2813
2814         if (sock->type == SOCK_PACKET)
2815                 po->prot_hook.func = packet_rcv_spkt;
2816
2817         po->prot_hook.af_packet_priv = sk;
2818
2819         if (proto) {
2820                 po->prot_hook.type = proto;
2821                 register_prot_hook(sk);
2822         }
2823
2824         mutex_lock(&net->packet.sklist_lock);
2825         sk_add_node_rcu(sk, &net->packet.sklist);
2826         mutex_unlock(&net->packet.sklist_lock);
2827
2828         preempt_disable();
2829         sock_prot_inuse_add(net, &packet_proto, 1);
2830         preempt_enable();
2831
2832         return 0;
2833 out2:
2834         sk_free(sk);
2835 out:
2836         return err;
2837 }
2838
2839 /*
2840  *      Pull a packet from our receive queue and hand it to the user.
2841  *      If necessary we block.
2842  */
2843
2844 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
2845                           struct msghdr *msg, size_t len, int flags)
2846 {
2847         struct sock *sk = sock->sk;
2848         struct sk_buff *skb;
2849         int copied, err;
2850         int vnet_hdr_len = 0;
2851
2852         err = -EINVAL;
2853         if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
2854                 goto out;
2855
2856 #if 0
2857         /* What error should we return now? EUNATTACH? */
2858         if (pkt_sk(sk)->ifindex < 0)
2859                 return -ENODEV;
2860 #endif
2861
2862         if (flags & MSG_ERRQUEUE) {
2863                 err = sock_recv_errqueue(sk, msg, len,
2864                                          SOL_PACKET, PACKET_TX_TIMESTAMP);
2865                 goto out;
2866         }
2867
2868         /*
2869          *      Call the generic datagram receiver. This handles all sorts
2870          *      of horrible races and re-entrancy so we can forget about it
2871          *      in the protocol layers.
2872          *
2873          *      Now it will return ENETDOWN, if device have just gone down,
2874          *      but then it will block.
2875          */
2876
2877         skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
2878
2879         /*
2880          *      An error occurred so return it. Because skb_recv_datagram()
2881          *      handles the blocking we don't see and worry about blocking
2882          *      retries.
2883          */
2884
2885         if (skb == NULL)
2886                 goto out;
2887
2888         if (pkt_sk(sk)->has_vnet_hdr) {
2889                 struct virtio_net_hdr vnet_hdr = { 0 };
2890
2891                 err = -EINVAL;
2892                 vnet_hdr_len = sizeof(vnet_hdr);
2893                 if (len < vnet_hdr_len)
2894                         goto out_free;
2895
2896                 len -= vnet_hdr_len;
2897
2898                 if (skb_is_gso(skb)) {
2899                         struct skb_shared_info *sinfo = skb_shinfo(skb);
2900
2901                         /* This is a hint as to how much should be linear. */
2902                         vnet_hdr.hdr_len = skb_headlen(skb);
2903                         vnet_hdr.gso_size = sinfo->gso_size;
2904                         if (sinfo->gso_type & SKB_GSO_TCPV4)
2905                                 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
2906                         else if (sinfo->gso_type & SKB_GSO_TCPV6)
2907                                 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
2908                         else if (sinfo->gso_type & SKB_GSO_UDP)
2909                                 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
2910                         else if (sinfo->gso_type & SKB_GSO_FCOE)
2911                                 goto out_free;
2912                         else
2913                                 BUG();
2914                         if (sinfo->gso_type & SKB_GSO_TCP_ECN)
2915                                 vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
2916                 } else
2917                         vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
2918
2919                 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2920                         vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
2921                         vnet_hdr.csum_start = skb_checksum_start_offset(skb);
2922                         vnet_hdr.csum_offset = skb->csum_offset;
2923                 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
2924                         vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID;
2925                 } /* else everything is zero */
2926
2927                 err = memcpy_toiovec(msg->msg_iov, (void *)&vnet_hdr,
2928                                      vnet_hdr_len);
2929                 if (err < 0)
2930                         goto out_free;
2931         }
2932
2933         /* You lose any data beyond the buffer you gave. If it worries
2934          * a user program they can ask the device for its MTU
2935          * anyway.
2936          */
2937         copied = skb->len;
2938         if (copied > len) {
2939                 copied = len;
2940                 msg->msg_flags |= MSG_TRUNC;
2941         }
2942
2943         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
2944         if (err)
2945                 goto out_free;
2946
2947         sock_recv_ts_and_drops(msg, sk, skb);
2948
2949         if (msg->msg_name) {
2950                 /* If the address length field is there to be filled
2951                  * in, we fill it in now.
2952                  */
2953                 if (sock->type == SOCK_PACKET) {
2954                         __sockaddr_check_size(sizeof(struct sockaddr_pkt));
2955                         msg->msg_namelen = sizeof(struct sockaddr_pkt);
2956                 } else {
2957                         struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
2958                         msg->msg_namelen = sll->sll_halen +
2959                                 offsetof(struct sockaddr_ll, sll_addr);
2960                 }
2961                 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
2962                        msg->msg_namelen);
2963         }
2964
2965         if (pkt_sk(sk)->auxdata) {
2966                 struct tpacket_auxdata aux;
2967
2968                 aux.tp_status = TP_STATUS_USER;
2969                 if (skb->ip_summed == CHECKSUM_PARTIAL)
2970                         aux.tp_status |= TP_STATUS_CSUMNOTREADY;
2971                 aux.tp_len = PACKET_SKB_CB(skb)->origlen;
2972                 aux.tp_snaplen = skb->len;
2973                 aux.tp_mac = 0;
2974                 aux.tp_net = skb_network_offset(skb);
2975                 if (vlan_tx_tag_present(skb)) {
2976                         aux.tp_vlan_tci = vlan_tx_tag_get(skb);
2977                         aux.tp_vlan_tpid = ntohs(skb->vlan_proto);
2978                         aux.tp_status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
2979                 } else {
2980                         aux.tp_vlan_tci = 0;
2981                         aux.tp_vlan_tpid = 0;
2982                 }
2983                 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
2984         }
2985
2986         /*
2987          *      Free or return the buffer as appropriate. Again this
2988          *      hides all the races and re-entrancy issues from us.
2989          */
2990         err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
2991
2992 out_free:
2993         skb_free_datagram(sk, skb);
2994 out:
2995         return err;
2996 }
2997
2998 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
2999                                int *uaddr_len, int peer)
3000 {
3001         struct net_device *dev;
3002         struct sock *sk = sock->sk;
3003
3004         if (peer)
3005                 return -EOPNOTSUPP;
3006
3007         uaddr->sa_family = AF_PACKET;
3008         memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data));
3009         rcu_read_lock();
3010         dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
3011         if (dev)
3012                 strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data));
3013         rcu_read_unlock();
3014         *uaddr_len = sizeof(*uaddr);
3015
3016         return 0;
3017 }
3018
3019 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
3020                           int *uaddr_len, int peer)
3021 {
3022         struct net_device *dev;
3023         struct sock *sk = sock->sk;
3024         struct packet_sock *po = pkt_sk(sk);
3025         DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
3026
3027         if (peer)
3028                 return -EOPNOTSUPP;
3029
3030         sll->sll_family = AF_PACKET;
3031         sll->sll_ifindex = po->ifindex;
3032         sll->sll_protocol = po->num;
3033         sll->sll_pkttype = 0;
3034         rcu_read_lock();
3035         dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
3036         if (dev) {
3037                 sll->sll_hatype = dev->type;
3038                 sll->sll_halen = dev->addr_len;
3039                 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
3040         } else {
3041                 sll->sll_hatype = 0;    /* Bad: we have no ARPHRD_UNSPEC */
3042                 sll->sll_halen = 0;
3043         }
3044         rcu_read_unlock();
3045         *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
3046
3047         return 0;
3048 }
3049
3050 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
3051                          int what)
3052 {
3053         switch (i->type) {
3054         case PACKET_MR_MULTICAST:
3055                 if (i->alen != dev->addr_len)
3056                         return -EINVAL;
3057                 if (what > 0)
3058                         return dev_mc_add(dev, i->addr);
3059                 else
3060                         return dev_mc_del(dev, i->addr);
3061                 break;
3062         case PACKET_MR_PROMISC:
3063                 return dev_set_promiscuity(dev, what);
3064                 break;
3065         case PACKET_MR_ALLMULTI:
3066                 return dev_set_allmulti(dev, what);
3067                 break;
3068         case PACKET_MR_UNICAST:
3069                 if (i->alen != dev->addr_len)
3070                         return -EINVAL;
3071                 if (what > 0)
3072                         return dev_uc_add(dev, i->addr);
3073                 else
3074                         return dev_uc_del(dev, i->addr);
3075                 break;
3076         default:
3077                 break;
3078         }
3079         return 0;
3080 }
3081
3082 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
3083 {
3084         for ( ; i; i = i->next) {
3085                 if (i->ifindex == dev->ifindex)
3086                         packet_dev_mc(dev, i, what);
3087         }
3088 }
3089
3090 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
3091 {
3092         struct packet_sock *po = pkt_sk(sk);
3093         struct packet_mclist *ml, *i;
3094         struct net_device *dev;
3095         int err;
3096
3097         rtnl_lock();
3098
3099         err = -ENODEV;
3100         dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
3101         if (!dev)
3102                 goto done;
3103
3104         err = -EINVAL;
3105         if (mreq->mr_alen > dev->addr_len)
3106                 goto done;
3107
3108         err = -ENOBUFS;
3109         i = kmalloc(sizeof(*i), GFP_KERNEL);
3110         if (i == NULL)
3111                 goto done;
3112
3113         err = 0;
3114         for (ml = po->mclist; ml; ml = ml->next) {
3115                 if (ml->ifindex == mreq->mr_ifindex &&
3116                     ml->type == mreq->mr_type &&
3117                     ml->alen == mreq->mr_alen &&
3118                     memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3119                         ml->count++;
3120                         /* Free the new element ... */
3121                         kfree(i);
3122                         goto done;
3123                 }
3124         }
3125
3126         i->type = mreq->mr_type;
3127         i->ifindex = mreq->mr_ifindex;
3128         i->alen = mreq->mr_alen;
3129         memcpy(i->addr, mreq->mr_address, i->alen);
3130         i->count = 1;
3131         i->next = po->mclist;
3132         po->mclist = i;
3133         err = packet_dev_mc(dev, i, 1);
3134         if (err) {
3135                 po->mclist = i->next;
3136                 kfree(i);
3137         }
3138
3139 done:
3140         rtnl_unlock();
3141         return err;
3142 }
3143
3144 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
3145 {
3146         struct packet_mclist *ml, **mlp;
3147
3148         rtnl_lock();
3149
3150         for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
3151                 if (ml->ifindex == mreq->mr_ifindex &&
3152                     ml->type == mreq->mr_type &&
3153                     ml->alen == mreq->mr_alen &&
3154                     memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3155                         if (--ml->count == 0) {
3156                                 struct net_device *dev;
3157                                 *mlp = ml->next;
3158                                 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3159                                 if (dev)
3160                                         packet_dev_mc(dev, ml, -1);
3161                                 kfree(ml);
3162                         }
3163                         rtnl_unlock();
3164                         return 0;
3165                 }
3166         }
3167         rtnl_unlock();
3168         return -EADDRNOTAVAIL;
3169 }
3170
3171 static void packet_flush_mclist(struct sock *sk)
3172 {
3173         struct packet_sock *po = pkt_sk(sk);
3174         struct packet_mclist *ml;
3175
3176         if (!po->mclist)
3177                 return;
3178
3179         rtnl_lock();
3180         while ((ml = po->mclist) != NULL) {
3181                 struct net_device *dev;
3182
3183                 po->mclist = ml->next;
3184                 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3185                 if (dev != NULL)
3186                         packet_dev_mc(dev, ml, -1);
3187                 kfree(ml);
3188         }
3189         rtnl_unlock();
3190 }
3191
3192 static int
3193 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
3194 {
3195         struct sock *sk = sock->sk;
3196         struct packet_sock *po = pkt_sk(sk);
3197         int ret;
3198
3199         if (level != SOL_PACKET)
3200                 return -ENOPROTOOPT;
3201
3202         switch (optname) {
3203         case PACKET_ADD_MEMBERSHIP:
3204         case PACKET_DROP_MEMBERSHIP:
3205         {
3206                 struct packet_mreq_max mreq;
3207                 int len = optlen;
3208                 memset(&mreq, 0, sizeof(mreq));
3209                 if (len < sizeof(struct packet_mreq))
3210                         return -EINVAL;
3211                 if (len > sizeof(mreq))
3212                         len = sizeof(mreq);
3213                 if (copy_from_user(&mreq, optval, len))
3214                         return -EFAULT;
3215                 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
3216                         return -EINVAL;
3217                 if (optname == PACKET_ADD_MEMBERSHIP)
3218                         ret = packet_mc_add(sk, &mreq);
3219                 else
3220                         ret = packet_mc_drop(sk, &mreq);
3221                 return ret;
3222         }
3223
3224         case PACKET_RX_RING:
3225         case PACKET_TX_RING:
3226         {
3227                 union tpacket_req_u req_u;
3228                 int len;
3229
3230                 switch (po->tp_version) {
3231                 case TPACKET_V1:
3232                 case TPACKET_V2:
3233                         len = sizeof(req_u.req);
3234                         break;
3235                 case TPACKET_V3:
3236                 default:
3237                         len = sizeof(req_u.req3);
3238                         break;
3239                 }
3240                 if (optlen < len)
3241                         return -EINVAL;
3242                 if (pkt_sk(sk)->has_vnet_hdr)
3243                         return -EINVAL;
3244                 if (copy_from_user(&req_u.req, optval, len))
3245                         return -EFAULT;
3246                 return packet_set_ring(sk, &req_u, 0,
3247                         optname == PACKET_TX_RING);
3248         }
3249         case PACKET_COPY_THRESH:
3250         {
3251                 int val;
3252
3253                 if (optlen != sizeof(val))
3254                         return -EINVAL;
3255                 if (copy_from_user(&val, optval, sizeof(val)))
3256                         return -EFAULT;
3257
3258                 pkt_sk(sk)->copy_thresh = val;
3259                 return 0;
3260         }
3261         case PACKET_VERSION:
3262         {
3263                 int val;
3264
3265                 if (optlen != sizeof(val))
3266                         return -EINVAL;
3267                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3268                         return -EBUSY;
3269                 if (copy_from_user(&val, optval, sizeof(val)))
3270                         return -EFAULT;
3271                 switch (val) {
3272                 case TPACKET_V1:
3273                 case TPACKET_V2:
3274                 case TPACKET_V3:
3275                         po->tp_version = val;
3276                         return 0;
3277                 default:
3278                         return -EINVAL;
3279                 }
3280         }
3281         case PACKET_RESERVE:
3282         {
3283                 unsigned int val;
3284
3285                 if (optlen != sizeof(val))
3286                         return -EINVAL;
3287                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3288                         return -EBUSY;
3289                 if (copy_from_user(&val, optval, sizeof(val)))
3290                         return -EFAULT;
3291                 po->tp_reserve = val;
3292                 return 0;
3293         }
3294         case PACKET_LOSS:
3295         {
3296                 unsigned int val;
3297
3298                 if (optlen != sizeof(val))
3299                         return -EINVAL;
3300                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3301                         return -EBUSY;
3302                 if (copy_from_user(&val, optval, sizeof(val)))
3303                         return -EFAULT;
3304                 po->tp_loss = !!val;
3305                 return 0;
3306         }
3307         case PACKET_AUXDATA:
3308         {
3309                 int val;
3310
3311                 if (optlen < sizeof(val))
3312                         return -EINVAL;
3313                 if (copy_from_user(&val, optval, sizeof(val)))
3314                         return -EFAULT;
3315
3316                 po->auxdata = !!val;
3317                 return 0;
3318         }
3319         case PACKET_ORIGDEV:
3320         {
3321                 int val;
3322
3323                 if (optlen < sizeof(val))
3324                         return -EINVAL;
3325                 if (copy_from_user(&val, optval, sizeof(val)))
3326                         return -EFAULT;
3327
3328                 po->origdev = !!val;
3329                 return 0;
3330         }
3331         case PACKET_VNET_HDR:
3332         {
3333                 int val;
3334
3335                 if (sock->type != SOCK_RAW)
3336                         return -EINVAL;
3337                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3338                         return -EBUSY;
3339                 if (optlen < sizeof(val))
3340                         return -EINVAL;
3341                 if (copy_from_user(&val, optval, sizeof(val)))
3342                         return -EFAULT;
3343
3344                 po->has_vnet_hdr = !!val;
3345                 return 0;
3346         }
3347         case PACKET_TIMESTAMP:
3348         {
3349                 int val;
3350
3351                 if (optlen != sizeof(val))
3352                         return -EINVAL;
3353                 if (copy_from_user(&val, optval, sizeof(val)))
3354                         return -EFAULT;
3355
3356                 po->tp_tstamp = val;
3357                 return 0;
3358         }
3359         case PACKET_FANOUT:
3360         {
3361                 int val;
3362
3363                 if (optlen != sizeof(val))
3364                         return -EINVAL;
3365                 if (copy_from_user(&val, optval, sizeof(val)))
3366                         return -EFAULT;
3367
3368                 return fanout_add(sk, val & 0xffff, val >> 16);
3369         }
3370         case PACKET_TX_HAS_OFF:
3371         {
3372                 unsigned int val;
3373
3374                 if (optlen != sizeof(val))
3375                         return -EINVAL;
3376                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3377                         return -EBUSY;
3378                 if (copy_from_user(&val, optval, sizeof(val)))
3379                         return -EFAULT;
3380                 po->tp_tx_has_off = !!val;
3381                 return 0;
3382         }
3383         case PACKET_QDISC_BYPASS:
3384         {
3385                 int val;
3386
3387                 if (optlen != sizeof(val))
3388                         return -EINVAL;
3389                 if (copy_from_user(&val, optval, sizeof(val)))
3390                         return -EFAULT;
3391
3392                 po->xmit = val ? packet_direct_xmit : dev_queue_xmit;
3393                 return 0;
3394         }
3395         default:
3396                 return -ENOPROTOOPT;
3397         }
3398 }
3399
3400 static int packet_getsockopt(struct socket *sock, int level, int optname,
3401                              char __user *optval, int __user *optlen)
3402 {
3403         int len;
3404         int val, lv = sizeof(val);
3405         struct sock *sk = sock->sk;
3406         struct packet_sock *po = pkt_sk(sk);
3407         void *data = &val;
3408         union tpacket_stats_u st;
3409
3410         if (level != SOL_PACKET)
3411                 return -ENOPROTOOPT;
3412
3413         if (get_user(len, optlen))
3414                 return -EFAULT;
3415
3416         if (len < 0)
3417                 return -EINVAL;
3418
3419         switch (optname) {
3420         case PACKET_STATISTICS:
3421                 spin_lock_bh(&sk->sk_receive_queue.lock);
3422                 memcpy(&st, &po->stats, sizeof(st));
3423                 memset(&po->stats, 0, sizeof(po->stats));
3424                 spin_unlock_bh(&sk->sk_receive_queue.lock);
3425
3426                 if (po->tp_version == TPACKET_V3) {
3427                         lv = sizeof(struct tpacket_stats_v3);
3428                         st.stats3.tp_packets += st.stats3.tp_drops;
3429                         data = &st.stats3;
3430                 } else {
3431                         lv = sizeof(struct tpacket_stats);
3432                         st.stats1.tp_packets += st.stats1.tp_drops;
3433                         data = &st.stats1;
3434                 }
3435
3436                 break;
3437         case PACKET_AUXDATA:
3438                 val = po->auxdata;
3439                 break;
3440         case PACKET_ORIGDEV:
3441                 val = po->origdev;
3442                 break;
3443         case PACKET_VNET_HDR:
3444                 val = po->has_vnet_hdr;
3445                 break;
3446         case PACKET_VERSION:
3447                 val = po->tp_version;
3448                 break;
3449         case PACKET_HDRLEN:
3450                 if (len > sizeof(int))
3451                         len = sizeof(int);
3452                 if (copy_from_user(&val, optval, len))
3453                         return -EFAULT;
3454                 switch (val) {
3455                 case TPACKET_V1:
3456                         val = sizeof(struct tpacket_hdr);
3457                         break;
3458                 case TPACKET_V2:
3459                         val = sizeof(struct tpacket2_hdr);
3460                         break;
3461                 case TPACKET_V3:
3462                         val = sizeof(struct tpacket3_hdr);
3463                         break;
3464                 default:
3465                         return -EINVAL;
3466                 }
3467                 break;
3468         case PACKET_RESERVE:
3469                 val = po->tp_reserve;
3470                 break;
3471         case PACKET_LOSS:
3472                 val = po->tp_loss;
3473                 break;
3474         case PACKET_TIMESTAMP:
3475                 val = po->tp_tstamp;
3476                 break;
3477         case PACKET_FANOUT:
3478                 val = (po->fanout ?
3479                        ((u32)po->fanout->id |
3480                         ((u32)po->fanout->type << 16) |
3481                         ((u32)po->fanout->flags << 24)) :
3482                        0);
3483                 break;
3484         case PACKET_TX_HAS_OFF:
3485                 val = po->tp_tx_has_off;
3486                 break;
3487         case PACKET_QDISC_BYPASS:
3488                 val = packet_use_direct_xmit(po);
3489                 break;
3490         default:
3491                 return -ENOPROTOOPT;
3492         }
3493
3494         if (len > lv)
3495                 len = lv;
3496         if (put_user(len, optlen))
3497                 return -EFAULT;
3498         if (copy_to_user(optval, data, len))
3499                 return -EFAULT;
3500         return 0;
3501 }
3502
3503
3504 static int packet_notifier(struct notifier_block *this,
3505                            unsigned long msg, void *ptr)
3506 {
3507         struct sock *sk;
3508         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3509         struct net *net = dev_net(dev);
3510
3511         rcu_read_lock();
3512         sk_for_each_rcu(sk, &net->packet.sklist) {
3513                 struct packet_sock *po = pkt_sk(sk);
3514
3515                 switch (msg) {
3516                 case NETDEV_UNREGISTER:
3517                         if (po->mclist)
3518                                 packet_dev_mclist(dev, po->mclist, -1);
3519                         /* fallthrough */
3520
3521                 case NETDEV_DOWN:
3522                         if (dev->ifindex == po->ifindex) {
3523                                 spin_lock(&po->bind_lock);
3524                                 if (po->running) {
3525                                         __unregister_prot_hook(sk, false);
3526                                         sk->sk_err = ENETDOWN;
3527                                         if (!sock_flag(sk, SOCK_DEAD))
3528                                                 sk->sk_error_report(sk);
3529                                 }
3530                                 if (msg == NETDEV_UNREGISTER) {
3531                                         packet_cached_dev_reset(po);
3532                                         po->ifindex = -1;
3533                                         if (po->prot_hook.dev)
3534                                                 dev_put(po->prot_hook.dev);
3535                                         po->prot_hook.dev = NULL;
3536                                 }
3537                                 spin_unlock(&po->bind_lock);
3538                         }
3539                         break;
3540                 case NETDEV_UP:
3541                         if (dev->ifindex == po->ifindex) {
3542                                 spin_lock(&po->bind_lock);
3543                                 if (po->num)
3544                                         register_prot_hook(sk);
3545                                 spin_unlock(&po->bind_lock);
3546                         }
3547                         break;
3548                 }
3549         }
3550         rcu_read_unlock();
3551         return NOTIFY_DONE;
3552 }
3553
3554
3555 static int packet_ioctl(struct socket *sock, unsigned int cmd,
3556                         unsigned long arg)
3557 {
3558         struct sock *sk = sock->sk;
3559
3560         switch (cmd) {
3561         case SIOCOUTQ:
3562         {
3563                 int amount = sk_wmem_alloc_get(sk);
3564
3565                 return put_user(amount, (int __user *)arg);
3566         }
3567         case SIOCINQ:
3568         {
3569                 struct sk_buff *skb;
3570                 int amount = 0;
3571
3572                 spin_lock_bh(&sk->sk_receive_queue.lock);
3573                 skb = skb_peek(&sk->sk_receive_queue);
3574                 if (skb)
3575                         amount = skb->len;
3576                 spin_unlock_bh(&sk->sk_receive_queue.lock);
3577                 return put_user(amount, (int __user *)arg);
3578         }
3579         case SIOCGSTAMP:
3580                 return sock_get_timestamp(sk, (struct timeval __user *)arg);
3581         case SIOCGSTAMPNS:
3582                 return sock_get_timestampns(sk, (struct timespec __user *)arg);
3583
3584 #ifdef CONFIG_INET
3585         case SIOCADDRT:
3586         case SIOCDELRT:
3587         case SIOCDARP:
3588         case SIOCGARP:
3589         case SIOCSARP:
3590         case SIOCGIFADDR:
3591         case SIOCSIFADDR:
3592         case SIOCGIFBRDADDR:
3593         case SIOCSIFBRDADDR:
3594         case SIOCGIFNETMASK:
3595         case SIOCSIFNETMASK:
3596         case SIOCGIFDSTADDR:
3597         case SIOCSIFDSTADDR:
3598         case SIOCSIFFLAGS:
3599                 return inet_dgram_ops.ioctl(sock, cmd, arg);
3600 #endif
3601
3602         default:
3603                 return -ENOIOCTLCMD;
3604         }
3605         return 0;
3606 }
3607
3608 static unsigned int packet_poll(struct file *file, struct socket *sock,
3609                                 poll_table *wait)
3610 {
3611         struct sock *sk = sock->sk;
3612         struct packet_sock *po = pkt_sk(sk);
3613         unsigned int mask = datagram_poll(file, sock, wait);
3614
3615         spin_lock_bh(&sk->sk_receive_queue.lock);
3616         if (po->rx_ring.pg_vec) {
3617                 if (!packet_previous_rx_frame(po, &po->rx_ring,
3618                         TP_STATUS_KERNEL))
3619                         mask |= POLLIN | POLLRDNORM;
3620         }
3621         spin_unlock_bh(&sk->sk_receive_queue.lock);
3622         spin_lock_bh(&sk->sk_write_queue.lock);
3623         if (po->tx_ring.pg_vec) {
3624                 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
3625                         mask |= POLLOUT | POLLWRNORM;
3626         }
3627         spin_unlock_bh(&sk->sk_write_queue.lock);
3628         return mask;
3629 }
3630
3631
3632 /* Dirty? Well, I still did not learn better way to account
3633  * for user mmaps.
3634  */
3635
3636 static void packet_mm_open(struct vm_area_struct *vma)
3637 {
3638         struct file *file = vma->vm_file;
3639         struct socket *sock = file->private_data;
3640         struct sock *sk = sock->sk;
3641
3642         if (sk)
3643                 atomic_inc(&pkt_sk(sk)->mapped);
3644 }
3645
3646 static void packet_mm_close(struct vm_area_struct *vma)
3647 {
3648         struct file *file = vma->vm_file;
3649         struct socket *sock = file->private_data;
3650         struct sock *sk = sock->sk;
3651
3652         if (sk)
3653                 atomic_dec(&pkt_sk(sk)->mapped);
3654 }
3655
3656 static const struct vm_operations_struct packet_mmap_ops = {
3657         .open   =       packet_mm_open,
3658         .close  =       packet_mm_close,
3659 };
3660
3661 static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
3662                         unsigned int len)
3663 {
3664         int i;
3665
3666         for (i = 0; i < len; i++) {
3667                 if (likely(pg_vec[i].buffer)) {
3668                         if (is_vmalloc_addr(pg_vec[i].buffer))
3669                                 vfree(pg_vec[i].buffer);
3670                         else
3671                                 free_pages((unsigned long)pg_vec[i].buffer,
3672                                            order);
3673                         pg_vec[i].buffer = NULL;
3674                 }
3675         }
3676         kfree(pg_vec);
3677 }
3678
3679 static char *alloc_one_pg_vec_page(unsigned long order)
3680 {
3681         char *buffer;
3682         gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
3683                           __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
3684
3685         buffer = (char *) __get_free_pages(gfp_flags, order);
3686         if (buffer)
3687                 return buffer;
3688
3689         /* __get_free_pages failed, fall back to vmalloc */
3690         buffer = vzalloc((1 << order) * PAGE_SIZE);
3691         if (buffer)
3692                 return buffer;
3693
3694         /* vmalloc failed, lets dig into swap here */
3695         gfp_flags &= ~__GFP_NORETRY;
3696         buffer = (char *) __get_free_pages(gfp_flags, order);
3697         if (buffer)
3698                 return buffer;
3699
3700         /* complete and utter failure */
3701         return NULL;
3702 }
3703
3704 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
3705 {
3706         unsigned int block_nr = req->tp_block_nr;
3707         struct pgv *pg_vec;
3708         int i;
3709
3710         pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
3711         if (unlikely(!pg_vec))
3712                 goto out;
3713
3714         for (i = 0; i < block_nr; i++) {
3715                 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
3716                 if (unlikely(!pg_vec[i].buffer))
3717                         goto out_free_pgvec;
3718         }
3719
3720 out:
3721         return pg_vec;
3722
3723 out_free_pgvec:
3724         free_pg_vec(pg_vec, order, block_nr);
3725         pg_vec = NULL;
3726         goto out;
3727 }
3728
3729 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
3730                 int closing, int tx_ring)
3731 {
3732         struct pgv *pg_vec = NULL;
3733         struct packet_sock *po = pkt_sk(sk);
3734         int was_running, order = 0;
3735         struct packet_ring_buffer *rb;
3736         struct sk_buff_head *rb_queue;
3737         __be16 num;
3738         int err = -EINVAL;
3739         /* Added to avoid minimal code churn */
3740         struct tpacket_req *req = &req_u->req;
3741
3742         /* Opening a Tx-ring is NOT supported in TPACKET_V3 */
3743         if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) {
3744                 WARN(1, "Tx-ring is not supported.\n");
3745                 goto out;
3746         }
3747
3748         rb = tx_ring ? &po->tx_ring : &po->rx_ring;
3749         rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
3750
3751         err = -EBUSY;
3752         if (!closing) {
3753                 if (atomic_read(&po->mapped))
3754                         goto out;
3755                 if (packet_read_pending(rb))
3756                         goto out;
3757         }
3758
3759         if (req->tp_block_nr) {
3760                 /* Sanity tests and some calculations */
3761                 err = -EBUSY;
3762                 if (unlikely(rb->pg_vec))
3763                         goto out;
3764
3765                 switch (po->tp_version) {
3766                 case TPACKET_V1:
3767                         po->tp_hdrlen = TPACKET_HDRLEN;
3768                         break;
3769                 case TPACKET_V2:
3770                         po->tp_hdrlen = TPACKET2_HDRLEN;
3771                         break;
3772                 case TPACKET_V3:
3773                         po->tp_hdrlen = TPACKET3_HDRLEN;
3774                         break;
3775                 }
3776
3777                 err = -EINVAL;
3778                 if (unlikely((int)req->tp_block_size <= 0))
3779                         goto out;
3780                 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
3781                         goto out;
3782                 if (unlikely(req->tp_frame_size < po->tp_hdrlen +
3783                                         po->tp_reserve))
3784                         goto out;
3785                 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
3786                         goto out;
3787
3788                 rb->frames_per_block = req->tp_block_size/req->tp_frame_size;
3789                 if (unlikely(rb->frames_per_block <= 0))
3790                         goto out;
3791                 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
3792                                         req->tp_frame_nr))
3793                         goto out;
3794
3795                 err = -ENOMEM;
3796                 order = get_order(req->tp_block_size);
3797                 pg_vec = alloc_pg_vec(req, order);
3798                 if (unlikely(!pg_vec))
3799                         goto out;
3800                 switch (po->tp_version) {
3801                 case TPACKET_V3:
3802                 /* Transmit path is not supported. We checked
3803                  * it above but just being paranoid
3804                  */
3805                         if (!tx_ring)
3806                                 init_prb_bdqc(po, rb, pg_vec, req_u, tx_ring);
3807                         break;
3808                 default:
3809                         break;
3810                 }
3811         }
3812         /* Done */
3813         else {
3814                 err = -EINVAL;
3815                 if (unlikely(req->tp_frame_nr))
3816                         goto out;
3817         }
3818
3819         lock_sock(sk);
3820
3821         /* Detach socket from network */
3822         spin_lock(&po->bind_lock);
3823         was_running = po->running;
3824         num = po->num;
3825         if (was_running) {
3826                 po->num = 0;
3827                 __unregister_prot_hook(sk, false);
3828         }
3829         spin_unlock(&po->bind_lock);
3830
3831         synchronize_net();
3832
3833         err = -EBUSY;
3834         mutex_lock(&po->pg_vec_lock);
3835         if (closing || atomic_read(&po->mapped) == 0) {
3836                 err = 0;
3837                 spin_lock_bh(&rb_queue->lock);
3838                 swap(rb->pg_vec, pg_vec);
3839                 rb->frame_max = (req->tp_frame_nr - 1);
3840                 rb->head = 0;
3841                 rb->frame_size = req->tp_frame_size;
3842                 spin_unlock_bh(&rb_queue->lock);
3843
3844                 swap(rb->pg_vec_order, order);
3845                 swap(rb->pg_vec_len, req->tp_block_nr);
3846
3847                 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
3848                 po->prot_hook.func = (po->rx_ring.pg_vec) ?
3849                                                 tpacket_rcv : packet_rcv;
3850                 skb_queue_purge(rb_queue);
3851                 if (atomic_read(&po->mapped))
3852                         pr_err("packet_mmap: vma is busy: %d\n",
3853                                atomic_read(&po->mapped));
3854         }
3855         mutex_unlock(&po->pg_vec_lock);
3856
3857         spin_lock(&po->bind_lock);
3858         if (was_running) {
3859                 po->num = num;
3860                 register_prot_hook(sk);
3861         }
3862         spin_unlock(&po->bind_lock);
3863         if (closing && (po->tp_version > TPACKET_V2)) {
3864                 /* Because we don't support block-based V3 on tx-ring */
3865                 if (!tx_ring)
3866                         prb_shutdown_retire_blk_timer(po, tx_ring, rb_queue);
3867         }
3868         release_sock(sk);
3869
3870         if (pg_vec)
3871                 free_pg_vec(pg_vec, order, req->tp_block_nr);
3872 out:
3873         return err;
3874 }
3875
3876 static int packet_mmap(struct file *file, struct socket *sock,
3877                 struct vm_area_struct *vma)
3878 {
3879         struct sock *sk = sock->sk;
3880         struct packet_sock *po = pkt_sk(sk);
3881         unsigned long size, expected_size;
3882         struct packet_ring_buffer *rb;
3883         unsigned long start;
3884         int err = -EINVAL;
3885         int i;
3886
3887         if (vma->vm_pgoff)
3888                 return -EINVAL;
3889
3890         mutex_lock(&po->pg_vec_lock);
3891
3892         expected_size = 0;
3893         for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3894                 if (rb->pg_vec) {
3895                         expected_size += rb->pg_vec_len
3896                                                 * rb->pg_vec_pages
3897                                                 * PAGE_SIZE;
3898                 }
3899         }
3900
3901         if (expected_size == 0)
3902                 goto out;
3903
3904         size = vma->vm_end - vma->vm_start;
3905         if (size != expected_size)
3906                 goto out;
3907
3908         start = vma->vm_start;
3909         for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3910                 if (rb->pg_vec == NULL)
3911                         continue;
3912
3913                 for (i = 0; i < rb->pg_vec_len; i++) {
3914                         struct page *page;
3915                         void *kaddr = rb->pg_vec[i].buffer;
3916                         int pg_num;
3917
3918                         for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
3919                                 page = pgv_to_page(kaddr);
3920                                 err = vm_insert_page(vma, start, page);
3921                                 if (unlikely(err))
3922                                         goto out;
3923                                 start += PAGE_SIZE;
3924                                 kaddr += PAGE_SIZE;
3925                         }
3926                 }
3927         }
3928
3929         atomic_inc(&po->mapped);
3930         vma->vm_ops = &packet_mmap_ops;
3931         err = 0;
3932
3933 out:
3934         mutex_unlock(&po->pg_vec_lock);
3935         return err;
3936 }
3937
3938 static const struct proto_ops packet_ops_spkt = {
3939         .family =       PF_PACKET,
3940         .owner =        THIS_MODULE,
3941         .release =      packet_release,
3942         .bind =         packet_bind_spkt,
3943         .connect =      sock_no_connect,
3944         .socketpair =   sock_no_socketpair,
3945         .accept =       sock_no_accept,
3946         .getname =      packet_getname_spkt,
3947         .poll =         datagram_poll,
3948         .ioctl =        packet_ioctl,
3949         .listen =       sock_no_listen,
3950         .shutdown =     sock_no_shutdown,
3951         .setsockopt =   sock_no_setsockopt,
3952         .getsockopt =   sock_no_getsockopt,
3953         .sendmsg =      packet_sendmsg_spkt,
3954         .recvmsg =      packet_recvmsg,
3955         .mmap =         sock_no_mmap,
3956         .sendpage =     sock_no_sendpage,
3957 };
3958
3959 static const struct proto_ops packet_ops = {
3960         .family =       PF_PACKET,
3961         .owner =        THIS_MODULE,
3962         .release =      packet_release,
3963         .bind =         packet_bind,
3964         .connect =      sock_no_connect,
3965         .socketpair =   sock_no_socketpair,
3966         .accept =       sock_no_accept,
3967         .getname =      packet_getname,
3968         .poll =         packet_poll,
3969         .ioctl =        packet_ioctl,
3970         .listen =       sock_no_listen,
3971         .shutdown =     sock_no_shutdown,
3972         .setsockopt =   packet_setsockopt,
3973         .getsockopt =   packet_getsockopt,
3974         .sendmsg =      packet_sendmsg,
3975         .recvmsg =      packet_recvmsg,
3976         .mmap =         packet_mmap,
3977         .sendpage =     sock_no_sendpage,
3978 };
3979
3980 static const struct net_proto_family packet_family_ops = {
3981         .family =       PF_PACKET,
3982         .create =       packet_create,
3983         .owner  =       THIS_MODULE,
3984 };
3985
3986 static struct notifier_block packet_netdev_notifier = {
3987         .notifier_call =        packet_notifier,
3988 };
3989
3990 #ifdef CONFIG_PROC_FS
3991
3992 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
3993         __acquires(RCU)
3994 {
3995         struct net *net = seq_file_net(seq);
3996
3997         rcu_read_lock();
3998         return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
3999 }
4000
4001 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4002 {
4003         struct net *net = seq_file_net(seq);
4004         return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
4005 }
4006
4007 static void packet_seq_stop(struct seq_file *seq, void *v)
4008         __releases(RCU)
4009 {
4010         rcu_read_unlock();
4011 }
4012
4013 static int packet_seq_show(struct seq_file *seq, void *v)
4014 {
4015         if (v == SEQ_START_TOKEN)
4016                 seq_puts(seq, "sk       RefCnt Type Proto  Iface R Rmem   User   Inode\n");
4017         else {
4018                 struct sock *s = sk_entry(v);
4019                 const struct packet_sock *po = pkt_sk(s);
4020
4021                 seq_printf(seq,
4022                            "%pK %-6d %-4d %04x   %-5d %1d %-6u %-6u %-6lu\n",
4023                            s,
4024                            atomic_read(&s->sk_refcnt),
4025                            s->sk_type,
4026                            ntohs(po->num),
4027                            po->ifindex,
4028                            po->running,
4029                            atomic_read(&s->sk_rmem_alloc),
4030                            from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)),
4031                            sock_i_ino(s));
4032         }
4033
4034         return 0;
4035 }
4036
4037 static const struct seq_operations packet_seq_ops = {
4038         .start  = packet_seq_start,
4039         .next   = packet_seq_next,
4040         .stop   = packet_seq_stop,
4041         .show   = packet_seq_show,
4042 };
4043
4044 static int packet_seq_open(struct inode *inode, struct file *file)
4045 {
4046         return seq_open_net(inode, file, &packet_seq_ops,
4047                             sizeof(struct seq_net_private));
4048 }
4049
4050 static const struct file_operations packet_seq_fops = {
4051         .owner          = THIS_MODULE,
4052         .open           = packet_seq_open,
4053         .read           = seq_read,
4054         .llseek         = seq_lseek,
4055         .release        = seq_release_net,
4056 };
4057
4058 #endif
4059
4060 static int __net_init packet_net_init(struct net *net)
4061 {
4062         mutex_init(&net->packet.sklist_lock);
4063         INIT_HLIST_HEAD(&net->packet.sklist);
4064
4065         if (!proc_create("packet", 0, net->proc_net, &packet_seq_fops))
4066                 return -ENOMEM;
4067
4068         return 0;
4069 }
4070
4071 static void __net_exit packet_net_exit(struct net *net)
4072 {
4073         remove_proc_entry("packet", net->proc_net);
4074 }
4075
4076 static struct pernet_operations packet_net_ops = {
4077         .init = packet_net_init,
4078         .exit = packet_net_exit,
4079 };
4080
4081
4082 static void __exit packet_exit(void)
4083 {
4084         unregister_netdevice_notifier(&packet_netdev_notifier);
4085         unregister_pernet_subsys(&packet_net_ops);
4086         sock_unregister(PF_PACKET);
4087         proto_unregister(&packet_proto);
4088 }
4089
4090 static int __init packet_init(void)
4091 {
4092         int rc = proto_register(&packet_proto, 0);
4093
4094         if (rc != 0)
4095                 goto out;
4096
4097         sock_register(&packet_family_ops);
4098         register_pernet_subsys(&packet_net_ops);
4099         register_netdevice_notifier(&packet_netdev_notifier);
4100 out:
4101         return rc;
4102 }
4103
4104 module_init(packet_init);
4105 module_exit(packet_exit);
4106 MODULE_LICENSE("GPL");
4107 MODULE_ALIAS_NETPROTO(PF_PACKET);