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         int ret = NETDEV_TX_BUSY;
 247         u16 queue_map;
 248
 249         if (unlikely(!netif_running(dev) ||
 250                      !netif_carrier_ok(dev)))
 251                 goto drop;
 252
 253         features = netif_skb_features(skb);
 254         if (skb_needs_linearize(skb, features) &&
 255             __skb_linearize(skb))
 256                 goto drop;
 257
 258         queue_map = skb_get_queue_mapping(skb);
 259         txq = netdev_get_tx_queue(dev, queue_map);
 260
 261         local_bh_disable();
 262
 263         HARD_TX_LOCK(dev, txq, smp_processor_id());
 264         if (!netif_xmit_frozen_or_drv_stopped(txq)) {
 265                 ret = ops->ndo_start_xmit(skb, dev);
 266                 if (ret == NETDEV_TX_OK)
 267                         txq_trans_update(txq);
 268         }
 269         HARD_TX_UNLOCK(dev, txq);
 270
 271         local_bh_enable();
 272
 273         if (!dev_xmit_complete(ret))
 274                 kfree_skb(skb);
 275
 276         return ret;
 277 drop:
 278         atomic_long_inc(&dev->tx_dropped);
 279         kfree_skb(skb);
 280         return NET_XMIT_DROP;
 281 }
 282
 283 static struct net_device *packet_cached_dev_get(struct packet_sock *po)
 284 {
 285         struct net_device *dev;
 286
 287         rcu_read_lock();
 288         dev = rcu_dereference(po->cached_dev);
 289         if (likely(dev))
 290                 dev_hold(dev);
 291         rcu_read_unlock();
 292
 293         return dev;
 294 }
 295
 296 static void packet_cached_dev_assign(struct packet_sock *po,
 297                                      struct net_device *dev)
 298 {
 299         rcu_assign_pointer(po->cached_dev, dev);
 300 }
 301
 302 static void packet_cached_dev_reset(struct packet_sock *po)
 303 {
 304         RCU_INIT_POINTER(po->cached_dev, NULL);
 305 }
 306
 307 static bool packet_use_direct_xmit(const struct packet_sock *po)
 308 {
 309         return po->xmit == packet_direct_xmit;
 310 }
 311
 312 static u16 __packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
 313 {
 314         return (u16) raw_smp_processor_id() % dev->real_num_tx_queues;
 315 }
 316
 317 static void packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
 318 {
 319         const struct net_device_ops *ops = dev->netdev_ops;
 320         u16 queue_index;
 321
 322         if (ops->ndo_select_queue) {
 323                 queue_index = ops->ndo_select_queue(dev, skb, NULL,
 324                                                     __packet_pick_tx_queue);
 325                 queue_index = netdev_cap_txqueue(dev, queue_index);
 326         } else {
 327                 queue_index = __packet_pick_tx_queue(dev, skb);
 328         }
 329
 330         skb_set_queue_mapping(skb, queue_index);
 331 }
 332
 333 /* register_prot_hook must be invoked with the po->bind_lock held,
 334  * or from a context in which asynchronous accesses to the packet
 335  * socket is not possible (packet_create()).
 336  */
 337 static void register_prot_hook(struct sock *sk)
 338 {
 339         struct packet_sock *po = pkt_sk(sk);
 340
 341         if (!po->running) {
 342                 if (po->fanout)
 343                         __fanout_link(sk, po);
 344                 else
 345                         dev_add_pack(&po->prot_hook);
 346
 347                 sock_hold(sk);
 348                 po->running = 1;
 349         }
 350 }
 351
 352 /* {,__}unregister_prot_hook() must be invoked with the po->bind_lock
 353  * held.   If the sync parameter is true, we will temporarily drop
 354  * the po->bind_lock and do a synchronize_net to make sure no
 355  * asynchronous packet processing paths still refer to the elements
 356  * of po->prot_hook.  If the sync parameter is false, it is the
 357  * callers responsibility to take care of this.
 358  */
 359 static void __unregister_prot_hook(struct sock *sk, bool sync)
 360 {
 361         struct packet_sock *po = pkt_sk(sk);
 362
 363         po->running = 0;
 364
 365         if (po->fanout)
 366                 __fanout_unlink(sk, po);
 367         else
 368                 __dev_remove_pack(&po->prot_hook);
 369
 370         __sock_put(sk);
 371
 372         if (sync) {
 373                 spin_unlock(&po->bind_lock);
 374                 synchronize_net();
 375                 spin_lock(&po->bind_lock);
 376         }
 377 }
 378
 379 static void unregister_prot_hook(struct sock *sk, bool sync)
 380 {
 381         struct packet_sock *po = pkt_sk(sk);
 382
 383         if (po->running)
 384                 __unregister_prot_hook(sk, sync);
 385 }
 386
 387 static inline __pure struct page *pgv_to_page(void *addr)
 388 {
 389         if (is_vmalloc_addr(addr))
 390                 return vmalloc_to_page(addr);
 391         return virt_to_page(addr);
 392 }
 393
 394 static void __packet_set_status(struct packet_sock *po, void *frame, int status)
 395 {
 396         union tpacket_uhdr h;
 397
 398         h.raw = frame;
 399         switch (po->tp_version) {
 400         case TPACKET_V1:
 401                 h.h1->tp_status = status;
 402                 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
 403                 break;
 404         case TPACKET_V2:
 405                 h.h2->tp_status = status;
 406                 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
 407                 break;
 408         case TPACKET_V3:
 409         default:
 410                 WARN(1, "TPACKET version not supported.\n");
 411                 BUG();
 412         }
 413
 414         smp_wmb();
 415 }
 416
 417 static int __packet_get_status(struct packet_sock *po, void *frame)
 418 {
 419         union tpacket_uhdr h;
 420
 421         smp_rmb();
 422
 423         h.raw = frame;
 424         switch (po->tp_version) {
 425         case TPACKET_V1:
 426                 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
 427                 return h.h1->tp_status;
 428         case TPACKET_V2:
 429                 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
 430                 return h.h2->tp_status;
 431         case TPACKET_V3:
 432         default:
 433                 WARN(1, "TPACKET version not supported.\n");
 434                 BUG();
 435                 return 0;
 436         }
 437 }
 438
 439 static __u32 tpacket_get_timestamp(struct sk_buff *skb, struct timespec *ts,
 440                                    unsigned int flags)
 441 {
 442         struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
 443
 444         if (shhwtstamps) {
 445                 if ((flags & SOF_TIMESTAMPING_SYS_HARDWARE) &&
 446                     ktime_to_timespec_cond(shhwtstamps->syststamp, ts))
 447                         return TP_STATUS_TS_SYS_HARDWARE;
 448                 if ((flags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
 449                     ktime_to_timespec_cond(shhwtstamps->hwtstamp, ts))
 450                         return TP_STATUS_TS_RAW_HARDWARE;
 451         }
 452
 453         if (ktime_to_timespec_cond(skb->tstamp, ts))
 454                 return TP_STATUS_TS_SOFTWARE;
 455
 456         return 0;
 457 }
 458
 459 static __u32 __packet_set_timestamp(struct packet_sock *po, void *frame,
 460                                     struct sk_buff *skb)
 461 {
 462         union tpacket_uhdr h;
 463         struct timespec ts;
 464         __u32 ts_status;
 465
 466         if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
 467                 return 0;
 468
 469         h.raw = frame;
 470         switch (po->tp_version) {
 471         case TPACKET_V1:
 472                 h.h1->tp_sec = ts.tv_sec;
 473                 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
 474                 break;
 475         case TPACKET_V2:
 476                 h.h2->tp_sec = ts.tv_sec;
 477                 h.h2->tp_nsec = ts.tv_nsec;
 478                 break;
 479         case TPACKET_V3:
 480         default:
 481                 WARN(1, "TPACKET version not supported.\n");
 482                 BUG();
 483         }
 484
 485         /* one flush is safe, as both fields always lie on the same cacheline */
 486         flush_dcache_page(pgv_to_page(&h.h1->tp_sec));
 487         smp_wmb();
 488
 489         return ts_status;
 490 }
 491
 492 static void *packet_lookup_frame(struct packet_sock *po,
 493                 struct packet_ring_buffer *rb,
 494                 unsigned int position,
 495                 int status)
 496 {
 497         unsigned int pg_vec_pos, frame_offset;
 498         union tpacket_uhdr h;
 499
 500         pg_vec_pos = position / rb->frames_per_block;
 501         frame_offset = position % rb->frames_per_block;
 502
 503         h.raw = rb->pg_vec[pg_vec_pos].buffer +
 504                 (frame_offset * rb->frame_size);
 505
 506         if (status != __packet_get_status(po, h.raw))
 507                 return NULL;
 508
 509         return h.raw;
 510 }
 511
 512 static void *packet_current_frame(struct packet_sock *po,
 513                 struct packet_ring_buffer *rb,
 514                 int status)
 515 {
 516         return packet_lookup_frame(po, rb, rb->head, status);
 517 }
 518
 519 static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc)
 520 {
 521         del_timer_sync(&pkc->retire_blk_timer);
 522 }
 523
 524 static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
 525                 int tx_ring,
 526                 struct sk_buff_head *rb_queue)
 527 {
 528         struct tpacket_kbdq_core *pkc;
 529
 530         pkc = tx_ring ? GET_PBDQC_FROM_RB(&po->tx_ring) :
 531                         GET_PBDQC_FROM_RB(&po->rx_ring);
 532
 533         spin_lock_bh(&rb_queue->lock);
 534         pkc->delete_blk_timer = 1;
 535         spin_unlock_bh(&rb_queue->lock);
 536
 537         prb_del_retire_blk_timer(pkc);
 538 }
 539
 540 static void prb_init_blk_timer(struct packet_sock *po,
 541                 struct tpacket_kbdq_core *pkc,
 542                 void (*func) (unsigned long))
 543 {
 544         init_timer(&pkc->retire_blk_timer);
 545         pkc->retire_blk_timer.data = (long)po;
 546         pkc->retire_blk_timer.function = func;
 547         pkc->retire_blk_timer.expires = jiffies;
 548 }
 549
 550 static void prb_setup_retire_blk_timer(struct packet_sock *po, int tx_ring)
 551 {
 552         struct tpacket_kbdq_core *pkc;
 553
 554         if (tx_ring)
 555                 BUG();
 556
 557         pkc = tx_ring ? GET_PBDQC_FROM_RB(&po->tx_ring) :
 558                         GET_PBDQC_FROM_RB(&po->rx_ring);
 559         prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired);
 560 }
 561
 562 static int prb_calc_retire_blk_tmo(struct packet_sock *po,
 563                                 int blk_size_in_bytes)
 564 {
 565         struct net_device *dev;
 566         unsigned int mbits = 0, msec = 0, div = 0, tmo = 0;
 567         struct ethtool_cmd ecmd;
 568         int err;
 569         u32 speed;
 570
 571         rtnl_lock();
 572         dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex);
 573         if (unlikely(!dev)) {
 574                 rtnl_unlock();
 575                 return DEFAULT_PRB_RETIRE_TOV;
 576         }
 577         err = __ethtool_get_settings(dev, &ecmd);
 578         speed = ethtool_cmd_speed(&ecmd);
 579         rtnl_unlock();
 580         if (!err) {
 581                 /*
 582                  * If the link speed is so slow you don't really
 583                  * need to worry about perf anyways
 584                  */
 585                 if (speed < SPEED_1000 || speed == SPEED_UNKNOWN) {
 586                         return DEFAULT_PRB_RETIRE_TOV;
 587                 } else {
 588                         msec = 1;
 589                         div = speed / 1000;
 590                 }
 591         }
 592
 593         mbits = (blk_size_in_bytes * 8) / (1024 * 1024);
 594
 595         if (div)
 596                 mbits /= div;
 597
 598         tmo = mbits * msec;
 599
 600         if (div)
 601                 return tmo+1;
 602         return tmo;
 603 }
 604
 605 static void prb_init_ft_ops(struct tpacket_kbdq_core *p1,
 606                         union tpacket_req_u *req_u)
 607 {
 608         p1->feature_req_word = req_u->req3.tp_feature_req_word;
 609 }
 610
 611 static void init_prb_bdqc(struct packet_sock *po,
 612                         struct packet_ring_buffer *rb,
 613                         struct pgv *pg_vec,
 614                         union tpacket_req_u *req_u, int tx_ring)
 615 {
 616         struct tpacket_kbdq_core *p1 = GET_PBDQC_FROM_RB(rb);
 617         struct tpacket_block_desc *pbd;
 618
 619         memset(p1, 0x0, sizeof(*p1));
 620
 621         p1->knxt_seq_num = 1;
 622         p1->pkbdq = pg_vec;
 623         pbd = (struct tpacket_block_desc *)pg_vec[0].buffer;
 624         p1->pkblk_start = pg_vec[0].buffer;
 625         p1->kblk_size = req_u->req3.tp_block_size;
 626         p1->knum_blocks = req_u->req3.tp_block_nr;
 627         p1->hdrlen = po->tp_hdrlen;
 628         p1->version = po->tp_version;
 629         p1->last_kactive_blk_num = 0;
 630         po->stats.stats3.tp_freeze_q_cnt = 0;
 631         if (req_u->req3.tp_retire_blk_tov)
 632                 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
 633         else
 634                 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
 635                                                 req_u->req3.tp_block_size);
 636         p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
 637         p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;
 638
 639         prb_init_ft_ops(p1, req_u);
 640         prb_setup_retire_blk_timer(po, tx_ring);
 641         prb_open_block(p1, pbd);
 642 }
 643
 644 /*  Do NOT update the last_blk_num first.
 645  *  Assumes sk_buff_head lock is held.
 646  */
 647 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
 648 {
 649         mod_timer(&pkc->retire_blk_timer,
 650                         jiffies + pkc->tov_in_jiffies);
 651         pkc->last_kactive_blk_num = pkc->kactive_blk_num;
 652 }
 653
 654 /*
 655  * Timer logic:
 656  * 1) We refresh the timer only when we open a block.
 657  *    By doing this we don't waste cycles refreshing the timer
 658  *        on packet-by-packet basis.
 659  *
 660  * With a 1MB block-size, on a 1Gbps line, it will take
 661  * i) ~8 ms to fill a block + ii) memcpy etc.
 662  * In this cut we are not accounting for the memcpy time.
 663  *
 664  * So, if the user sets the 'tmo' to 10ms then the timer
 665  * will never fire while the block is still getting filled
 666  * (which is what we want). However, the user could choose
 667  * to close a block early and that's fine.
 668  *
 669  * But when the timer does fire, we check whether or not to refresh it.
 670  * Since the tmo granularity is in msecs, it is not too expensive
 671  * to refresh the timer, lets say every '8' msecs.
 672  * Either the user can set the 'tmo' or we can derive it based on
 673  * a) line-speed and b) block-size.
 674  * prb_calc_retire_blk_tmo() calculates the tmo.
 675  *
 676  */
 677 static void prb_retire_rx_blk_timer_expired(unsigned long data)
 678 {
 679         struct packet_sock *po = (struct packet_sock *)data;
 680         struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
 681         unsigned int frozen;
 682         struct tpacket_block_desc *pbd;
 683
 684         spin_lock(&po->sk.sk_receive_queue.lock);
 685
 686         frozen = prb_queue_frozen(pkc);
 687         pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
 688
 689         if (unlikely(pkc->delete_blk_timer))
 690                 goto out;
 691
 692         /* We only need to plug the race when the block is partially filled.
 693          * tpacket_rcv:
 694          *              lock(); increment BLOCK_NUM_PKTS; unlock()
 695          *              copy_bits() is in progress ...
 696          *              timer fires on other cpu:
 697          *              we can't retire the current block because copy_bits
 698          *              is in progress.
 699          *
 700          */
 701         if (BLOCK_NUM_PKTS(pbd)) {
 702                 while (atomic_read(&pkc->blk_fill_in_prog)) {
 703                         /* Waiting for skb_copy_bits to finish... */
 704                         cpu_relax();
 705                 }
 706         }
 707
 708         if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) {
 709                 if (!frozen) {
 710                         prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
 711                         if (!prb_dispatch_next_block(pkc, po))
 712                                 goto refresh_timer;
 713                         else
 714                                 goto out;
 715                 } else {
 716                         /* Case 1. Queue was frozen because user-space was
 717                          *         lagging behind.
 718                          */
 719                         if (prb_curr_blk_in_use(pkc, pbd)) {
 720                                 /*
 721                                  * Ok, user-space is still behind.
 722                                  * So just refresh the timer.
 723                                  */
 724                                 goto refresh_timer;
 725                         } else {
 726                                /* Case 2. queue was frozen,user-space caught up,
 727                                 * now the link went idle && the timer fired.
 728                                 * We don't have a block to close.So we open this
 729                                 * block and restart the timer.
 730                                 * opening a block thaws the queue,restarts timer
 731                                 * Thawing/timer-refresh is a side effect.
 732                                 */
 733                                 prb_open_block(pkc, pbd);
 734                                 goto out;
 735                         }
 736                 }
 737         }
 738
 739 refresh_timer:
 740         _prb_refresh_rx_retire_blk_timer(pkc);
 741
 742 out:
 743         spin_unlock(&po->sk.sk_receive_queue.lock);
 744 }
 745
 746 static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
 747                 struct tpacket_block_desc *pbd1, __u32 status)
 748 {
 749         /* Flush everything minus the block header */
 750
 751 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
 752         u8 *start, *end;
 753
 754         start = (u8 *)pbd1;
 755
 756         /* Skip the block header(we know header WILL fit in 4K) */
 757         start += PAGE_SIZE;
 758
 759         end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end);
 760         for (; start < end; start += PAGE_SIZE)
 761                 flush_dcache_page(pgv_to_page(start));
 762
 763         smp_wmb();
 764 #endif
 765
 766         /* Now update the block status. */
 767
 768         BLOCK_STATUS(pbd1) = status;
 769
 770         /* Flush the block header */
 771
 772 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
 773         start = (u8 *)pbd1;
 774         flush_dcache_page(pgv_to_page(start));
 775
 776         smp_wmb();
 777 #endif
 778 }
 779
 780 /*
 781  * Side effect:
 782  *
 783  * 1) flush the block
 784  * 2) Increment active_blk_num
 785  *
 786  * Note:We DONT refresh the timer on purpose.
 787  *      Because almost always the next block will be opened.
 788  */
 789 static void prb_close_block(struct tpacket_kbdq_core *pkc1,
 790                 struct tpacket_block_desc *pbd1,
 791                 struct packet_sock *po, unsigned int stat)
 792 {
 793         __u32 status = TP_STATUS_USER | stat;
 794
 795         struct tpacket3_hdr *last_pkt;
 796         struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
 797
 798         if (po->stats.stats3.tp_drops)
 799                 status |= TP_STATUS_LOSING;
 800
 801         last_pkt = (struct tpacket3_hdr *)pkc1->prev;
 802         last_pkt->tp_next_offset = 0;
 803
 804         /* Get the ts of the last pkt */
 805         if (BLOCK_NUM_PKTS(pbd1)) {
 806                 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec;
 807                 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec;
 808         } else {
 809                 /* Ok, we tmo'd - so get the current time */
 810                 struct timespec ts;
 811                 getnstimeofday(&ts);
 812                 h1->ts_last_pkt.ts_sec = ts.tv_sec;
 813                 h1->ts_last_pkt.ts_nsec = ts.tv_nsec;
 814         }
 815
 816         smp_wmb();
 817
 818         /* Flush the block */
 819         prb_flush_block(pkc1, pbd1, status);
 820
 821         pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1);
 822 }
 823
 824 static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
 825 {
 826         pkc->reset_pending_on_curr_blk = 0;
 827 }
 828
 829 /*
 830  * Side effect of opening a block:
 831  *
 832  * 1) prb_queue is thawed.
 833  * 2) retire_blk_timer is refreshed.
 834  *
 835  */
 836 static void prb_open_block(struct tpacket_kbdq_core *pkc1,
 837         struct tpacket_block_desc *pbd1)
 838 {
 839         struct timespec ts;
 840         struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
 841
 842         smp_rmb();
 843
 844         /* We could have just memset this but we will lose the
 845          * flexibility of making the priv area sticky
 846          */
 847
 848         BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
 849         BLOCK_NUM_PKTS(pbd1) = 0;
 850         BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
 851
 852         getnstimeofday(&ts);
 853
 854         h1->ts_first_pkt.ts_sec = ts.tv_sec;
 855         h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
 856
 857         pkc1->pkblk_start = (char *)pbd1;
 858         pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
 859
 860         BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
 861         BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN;
 862
 863         pbd1->version = pkc1->version;
 864         pkc1->prev = pkc1->nxt_offset;
 865         pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;
 866
 867         prb_thaw_queue(pkc1);
 868         _prb_refresh_rx_retire_blk_timer(pkc1);
 869
 870         smp_wmb();
 871 }
 872
 873 /*
 874  * Queue freeze logic:
 875  * 1) Assume tp_block_nr = 8 blocks.
 876  * 2) At time 't0', user opens Rx ring.
 877  * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7
 878  * 4) user-space is either sleeping or processing block '0'.
 879  * 5) tpacket_rcv is currently filling block '7', since there is no space left,
 880  *    it will close block-7,loop around and try to fill block '0'.
 881  *    call-flow:
 882  *    __packet_lookup_frame_in_block
 883  *      prb_retire_current_block()
 884  *      prb_dispatch_next_block()
 885  *        |->(BLOCK_STATUS == USER) evaluates to true
 886  *    5.1) Since block-0 is currently in-use, we just freeze the queue.
 887  * 6) Now there are two cases:
 888  *    6.1) Link goes idle right after the queue is frozen.
 889  *         But remember, the last open_block() refreshed the timer.
 890  *         When this timer expires,it will refresh itself so that we can
 891  *         re-open block-0 in near future.
 892  *    6.2) Link is busy and keeps on receiving packets. This is a simple
 893  *         case and __packet_lookup_frame_in_block will check if block-0
 894  *         is free and can now be re-used.
 895  */
 896 static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
 897                                   struct packet_sock *po)
 898 {
 899         pkc->reset_pending_on_curr_blk = 1;
 900         po->stats.stats3.tp_freeze_q_cnt++;
 901 }
 902
 903 #define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT))
 904
 905 /*
 906  * If the next block is free then we will dispatch it
 907  * and return a good offset.
 908  * Else, we will freeze the queue.
 909  * So, caller must check the return value.
 910  */
 911 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
 912                 struct packet_sock *po)
 913 {
 914         struct tpacket_block_desc *pbd;
 915
 916         smp_rmb();
 917
 918         /* 1. Get current block num */
 919         pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
 920
 921         /* 2. If this block is currently in_use then freeze the queue */
 922         if (TP_STATUS_USER & BLOCK_STATUS(pbd)) {
 923                 prb_freeze_queue(pkc, po);
 924                 return NULL;
 925         }
 926
 927         /*
 928          * 3.
 929          * open this block and return the offset where the first packet
 930          * needs to get stored.
 931          */
 932         prb_open_block(pkc, pbd);
 933         return (void *)pkc->nxt_offset;
 934 }
 935
 936 static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
 937                 struct packet_sock *po, unsigned int status)
 938 {
 939         struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
 940
 941         /* retire/close the current block */
 942         if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) {
 943                 /*
 944                  * Plug the case where copy_bits() is in progress on
 945                  * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't
 946                  * have space to copy the pkt in the current block and
 947                  * called prb_retire_current_block()
 948                  *
 949                  * We don't need to worry about the TMO case because
 950                  * the timer-handler already handled this case.
 951                  */
 952                 if (!(status & TP_STATUS_BLK_TMO)) {
 953                         while (atomic_read(&pkc->blk_fill_in_prog)) {
 954                                 /* Waiting for skb_copy_bits to finish... */
 955                                 cpu_relax();
 956                         }
 957                 }
 958                 prb_close_block(pkc, pbd, po, status);
 959                 return;
 960         }
 961 }
 962
 963 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc,
 964                                       struct tpacket_block_desc *pbd)
 965 {
 966         return TP_STATUS_USER & BLOCK_STATUS(pbd);
 967 }
 968
 969 static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
 970 {
 971         return pkc->reset_pending_on_curr_blk;
 972 }
 973
 974 static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
 975 {
 976         struct tpacket_kbdq_core *pkc  = GET_PBDQC_FROM_RB(rb);
 977         atomic_dec(&pkc->blk_fill_in_prog);
 978 }
 979
 980 static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
 981                         struct tpacket3_hdr *ppd)
 982 {
 983         ppd->hv1.tp_rxhash = skb_get_hash(pkc->skb);
 984 }
 985
 986 static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
 987                         struct tpacket3_hdr *ppd)
 988 {
 989         ppd->hv1.tp_rxhash = 0;
 990 }
 991
 992 static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
 993                         struct tpacket3_hdr *ppd)
 994 {
 995         if (vlan_tx_tag_present(pkc->skb)) {
 996                 ppd->hv1.tp_vlan_tci = vlan_tx_tag_get(pkc->skb);
 997                 ppd->hv1.tp_vlan_tpid = ntohs(pkc->skb->vlan_proto);
 998                 ppd->tp_status = TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
 999         } else {
1000                 ppd->hv1.tp_vlan_tci = 0;
1001                 ppd->hv1.tp_vlan_tpid = 0;
1002                 ppd->tp_status = TP_STATUS_AVAILABLE;
1003         }
1004 }
1005
1006 static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
1007                         struct tpacket3_hdr *ppd)
1008 {
1009         ppd->hv1.tp_padding = 0;
1010         prb_fill_vlan_info(pkc, ppd);
1011
1012         if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH)
1013                 prb_fill_rxhash(pkc, ppd);
1014         else
1015                 prb_clear_rxhash(pkc, ppd);
1016 }
1017
1018 static void prb_fill_curr_block(char *curr,
1019                                 struct tpacket_kbdq_core *pkc,
1020                                 struct tpacket_block_desc *pbd,
1021                                 unsigned int len)
1022 {
1023         struct tpacket3_hdr *ppd;
1024
1025         ppd  = (struct tpacket3_hdr *)curr;
1026         ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len);
1027         pkc->prev = curr;
1028         pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len);
1029         BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len);
1030         BLOCK_NUM_PKTS(pbd) += 1;
1031         atomic_inc(&pkc->blk_fill_in_prog);
1032         prb_run_all_ft_ops(pkc, ppd);
1033 }
1034
1035 /* Assumes caller has the sk->rx_queue.lock */
1036 static void *__packet_lookup_frame_in_block(struct packet_sock *po,
1037                                             struct sk_buff *skb,
1038                                                 int status,
1039                                             unsigned int len
1040                                             )
1041 {
1042         struct tpacket_kbdq_core *pkc;
1043         struct tpacket_block_desc *pbd;
1044         char *curr, *end;
1045
1046         pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
1047         pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1048
1049         /* Queue is frozen when user space is lagging behind */
1050         if (prb_queue_frozen(pkc)) {
1051                 /*
1052                  * Check if that last block which caused the queue to freeze,
1053                  * is still in_use by user-space.
1054                  */
1055                 if (prb_curr_blk_in_use(pkc, pbd)) {
1056                         /* Can't record this packet */
1057                         return NULL;
1058                 } else {
1059                         /*
1060                          * Ok, the block was released by user-space.
1061                          * Now let's open that block.
1062                          * opening a block also thaws the queue.
1063                          * Thawing is a side effect.
1064                          */
1065                         prb_open_block(pkc, pbd);
1066                 }
1067         }
1068
1069         smp_mb();
1070         curr = pkc->nxt_offset;
1071         pkc->skb = skb;
1072         end = (char *)pbd + pkc->kblk_size;
1073
1074         /* first try the current block */
1075         if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) {
1076                 prb_fill_curr_block(curr, pkc, pbd, len);
1077                 return (void *)curr;
1078         }
1079
1080         /* Ok, close the current block */
1081         prb_retire_current_block(pkc, po, 0);
1082
1083         /* Now, try to dispatch the next block */
1084         curr = (char *)prb_dispatch_next_block(pkc, po);
1085         if (curr) {
1086                 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1087                 prb_fill_curr_block(curr, pkc, pbd, len);
1088                 return (void *)curr;
1089         }
1090
1091         /*
1092          * No free blocks are available.user_space hasn't caught up yet.
1093          * Queue was just frozen and now this packet will get dropped.
1094          */
1095         return NULL;
1096 }
1097
1098 static void *packet_current_rx_frame(struct packet_sock *po,
1099                                             struct sk_buff *skb,
1100                                             int status, unsigned int len)
1101 {
1102         char *curr = NULL;
1103         switch (po->tp_version) {
1104         case TPACKET_V1:
1105         case TPACKET_V2:
1106                 curr = packet_lookup_frame(po, &po->rx_ring,
1107                                         po->rx_ring.head, status);
1108                 return curr;
1109         case TPACKET_V3:
1110                 return __packet_lookup_frame_in_block(po, skb, status, len);
1111         default:
1112                 WARN(1, "TPACKET version not supported\n");
1113                 BUG();
1114                 return NULL;
1115         }
1116 }
1117
1118 static void *prb_lookup_block(struct packet_sock *po,
1119                                      struct packet_ring_buffer *rb,
1120                                      unsigned int idx,
1121                                      int status)
1122 {
1123         struct tpacket_kbdq_core *pkc  = GET_PBDQC_FROM_RB(rb);
1124         struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, idx);
1125
1126         if (status != BLOCK_STATUS(pbd))
1127                 return NULL;
1128         return pbd;
1129 }
1130
1131 static int prb_previous_blk_num(struct packet_ring_buffer *rb)
1132 {
1133         unsigned int prev;
1134         if (rb->prb_bdqc.kactive_blk_num)
1135                 prev = rb->prb_bdqc.kactive_blk_num-1;
1136         else
1137                 prev = rb->prb_bdqc.knum_blocks-1;
1138         return prev;
1139 }
1140
1141 /* Assumes caller has held the rx_queue.lock */
1142 static void *__prb_previous_block(struct packet_sock *po,
1143                                          struct packet_ring_buffer *rb,
1144                                          int status)
1145 {
1146         unsigned int previous = prb_previous_blk_num(rb);
1147         return prb_lookup_block(po, rb, previous, status);
1148 }
1149
1150 static void *packet_previous_rx_frame(struct packet_sock *po,
1151                                              struct packet_ring_buffer *rb,
1152                                              int status)
1153 {
1154         if (po->tp_version <= TPACKET_V2)
1155                 return packet_previous_frame(po, rb, status);
1156
1157         return __prb_previous_block(po, rb, status);
1158 }
1159
1160 static void packet_increment_rx_head(struct packet_sock *po,
1161                                             struct packet_ring_buffer *rb)
1162 {
1163         switch (po->tp_version) {
1164         case TPACKET_V1:
1165         case TPACKET_V2:
1166                 return packet_increment_head(rb);
1167         case TPACKET_V3:
1168         default:
1169                 WARN(1, "TPACKET version not supported.\n");
1170                 BUG();
1171                 return;
1172         }
1173 }
1174
1175 static void *packet_previous_frame(struct packet_sock *po,
1176                 struct packet_ring_buffer *rb,
1177                 int status)
1178 {
1179         unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
1180         return packet_lookup_frame(po, rb, previous, status);
1181 }
1182
1183 static void packet_increment_head(struct packet_ring_buffer *buff)
1184 {
1185         buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
1186 }
1187
1188 static void packet_inc_pending(struct packet_ring_buffer *rb)
1189 {
1190         this_cpu_inc(*rb->pending_refcnt);
1191 }
1192
1193 static void packet_dec_pending(struct packet_ring_buffer *rb)
1194 {
1195         this_cpu_dec(*rb->pending_refcnt);
1196 }
1197
1198 static unsigned int packet_read_pending(const struct packet_ring_buffer *rb)
1199 {
1200         unsigned int refcnt = 0;
1201         int cpu;
1202
1203         /* We don't use pending refcount in rx_ring. */
1204         if (rb->pending_refcnt == NULL)
1205                 return 0;
1206
1207         for_each_possible_cpu(cpu)
1208                 refcnt += *per_cpu_ptr(rb->pending_refcnt, cpu);
1209
1210         return refcnt;
1211 }
1212
1213 static int packet_alloc_pending(struct packet_sock *po)
1214 {
1215         po->rx_ring.pending_refcnt = NULL;
1216
1217         po->tx_ring.pending_refcnt = alloc_percpu(unsigned int);
1218         if (unlikely(po->tx_ring.pending_refcnt == NULL))
1219                 return -ENOBUFS;
1220
1221         return 0;
1222 }
1223
1224 static void packet_free_pending(struct packet_sock *po)
1225 {
1226         free_percpu(po->tx_ring.pending_refcnt);
1227 }
1228
1229 static bool packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1230 {
1231         struct sock *sk = &po->sk;
1232         bool has_room;
1233
1234         if (po->prot_hook.func != tpacket_rcv)
1235                 return (atomic_read(&sk->sk_rmem_alloc) + skb->truesize)
1236                         <= sk->sk_rcvbuf;
1237
1238         spin_lock(&sk->sk_receive_queue.lock);
1239         if (po->tp_version == TPACKET_V3)
1240                 has_room = prb_lookup_block(po, &po->rx_ring,
1241                                             po->rx_ring.prb_bdqc.kactive_blk_num,
1242                                             TP_STATUS_KERNEL);
1243         else
1244                 has_room = packet_lookup_frame(po, &po->rx_ring,
1245                                                po->rx_ring.head,
1246                                                TP_STATUS_KERNEL);
1247         spin_unlock(&sk->sk_receive_queue.lock);
1248
1249         return has_room;
1250 }
1251
1252 static void packet_sock_destruct(struct sock *sk)
1253 {
1254         skb_queue_purge(&sk->sk_error_queue);
1255
1256         WARN_ON(atomic_read(&sk->sk_rmem_alloc));
1257         WARN_ON(atomic_read(&sk->sk_wmem_alloc));
1258
1259         if (!sock_flag(sk, SOCK_DEAD)) {
1260                 pr_err("Attempt to release alive packet socket: %p\n", sk);
1261                 return;
1262         }
1263
1264         sk_refcnt_debug_dec(sk);
1265 }
1266
1267 static int fanout_rr_next(struct packet_fanout *f, unsigned int num)
1268 {
1269         int x = atomic_read(&f->rr_cur) + 1;
1270
1271         if (x >= num)
1272                 x = 0;
1273
1274         return x;
1275 }
1276
1277 static unsigned int fanout_demux_hash(struct packet_fanout *f,
1278                                       struct sk_buff *skb,
1279                                       unsigned int num)
1280 {
1281         return reciprocal_scale(skb_get_hash(skb), num);
1282 }
1283
1284 static unsigned int fanout_demux_lb(struct packet_fanout *f,
1285                                     struct sk_buff *skb,
1286                                     unsigned int num)
1287 {
1288         int cur, old;
1289
1290         cur = atomic_read(&f->rr_cur);
1291         while ((old = atomic_cmpxchg(&f->rr_cur, cur,
1292                                      fanout_rr_next(f, num))) != cur)
1293                 cur = old;
1294         return cur;
1295 }
1296
1297 static unsigned int fanout_demux_cpu(struct packet_fanout *f,
1298                                      struct sk_buff *skb,
1299                                      unsigned int num)
1300 {
1301         return smp_processor_id() % num;
1302 }
1303
1304 static unsigned int fanout_demux_rnd(struct packet_fanout *f,
1305                                      struct sk_buff *skb,
1306                                      unsigned int num)
1307 {
1308         return prandom_u32_max(num);
1309 }
1310
1311 static unsigned int fanout_demux_rollover(struct packet_fanout *f,
1312                                           struct sk_buff *skb,
1313                                           unsigned int idx, unsigned int skip,
1314                                           unsigned int num)
1315 {
1316         unsigned int i, j;
1317
1318         i = j = min_t(int, f->next[idx], num - 1);
1319         do {
1320                 if (i != skip && packet_rcv_has_room(pkt_sk(f->arr[i]), skb)) {
1321                         if (i != j)
1322                                 f->next[idx] = i;
1323                         return i;
1324                 }
1325                 if (++i == num)
1326                         i = 0;
1327         } while (i != j);
1328
1329         return idx;
1330 }
1331
1332 static unsigned int fanout_demux_qm(struct packet_fanout *f,
1333                                     struct sk_buff *skb,
1334                                     unsigned int num)
1335 {
1336         return skb_get_queue_mapping(skb) % num;
1337 }
1338
1339 static bool fanout_has_flag(struct packet_fanout *f, u16 flag)
1340 {
1341         return f->flags & (flag >> 8);
1342 }
1343
1344 static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
1345                              struct packet_type *pt, struct net_device *orig_dev)
1346 {
1347         struct packet_fanout *f = pt->af_packet_priv;
1348         unsigned int num = f->num_members;
1349         struct packet_sock *po;
1350         unsigned int idx;
1351
1352         if (!net_eq(dev_net(dev), read_pnet(&f->net)) ||
1353             !num) {
1354                 kfree_skb(skb);
1355                 return 0;
1356         }
1357
1358         switch (f->type) {
1359         case PACKET_FANOUT_HASH:
1360         default:
1361                 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_DEFRAG)) {
1362                         skb = ip_check_defrag(skb, IP_DEFRAG_AF_PACKET);
1363                         if (!skb)
1364                                 return 0;
1365                 }
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);
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);
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);
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 + VLAN_HLEN;
2261         size_max = po->tx_ring.frame_size
2262                 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
2263
2264         if (size_max > dev->mtu + reserve)
2265                 size_max = dev->mtu + reserve;
2266
2267         do {
2268                 ph = packet_current_frame(po, &po->tx_ring,
2269                                           TP_STATUS_SEND_REQUEST);
2270                 if (unlikely(ph == NULL)) {
2271                         if (need_wait && need_resched())
2272                                 schedule();
2273                         continue;
2274                 }
2275
2276                 status = TP_STATUS_SEND_REQUEST;
2277                 hlen = LL_RESERVED_SPACE(dev);
2278                 tlen = dev->needed_tailroom;
2279                 skb = sock_alloc_send_skb(&po->sk,
2280                                 hlen + tlen + sizeof(struct sockaddr_ll),
2281                                 0, &err);
2282
2283                 if (unlikely(skb == NULL))
2284                         goto out_status;
2285
2286                 tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
2287                                           addr, hlen);
2288                 if (tp_len > dev->mtu + dev->hard_header_len) {
2289                         struct ethhdr *ehdr;
2290                         /* Earlier code assumed this would be a VLAN pkt,
2291                          * double-check this now that we have the actual
2292                          * packet in hand.
2293                          */
2294
2295                         skb_reset_mac_header(skb);
2296                         ehdr = eth_hdr(skb);
2297                         if (ehdr->h_proto != htons(ETH_P_8021Q))
2298                                 tp_len = -EMSGSIZE;
2299                 }
2300                 if (unlikely(tp_len < 0)) {
2301                         if (po->tp_loss) {
2302                                 __packet_set_status(po, ph,
2303                                                 TP_STATUS_AVAILABLE);
2304                                 packet_increment_head(&po->tx_ring);
2305                                 kfree_skb(skb);
2306                                 continue;
2307                         } else {
2308                                 status = TP_STATUS_WRONG_FORMAT;
2309                                 err = tp_len;
2310                                 goto out_status;
2311                         }
2312                 }
2313
2314                 packet_pick_tx_queue(dev, skb);
2315
2316                 skb->destructor = tpacket_destruct_skb;
2317                 __packet_set_status(po, ph, TP_STATUS_SENDING);
2318                 packet_inc_pending(&po->tx_ring);
2319
2320                 status = TP_STATUS_SEND_REQUEST;
2321                 err = po->xmit(skb);
2322                 if (unlikely(err > 0)) {
2323                         err = net_xmit_errno(err);
2324                         if (err && __packet_get_status(po, ph) ==
2325                                    TP_STATUS_AVAILABLE) {
2326                                 /* skb was destructed already */
2327                                 skb = NULL;
2328                                 goto out_status;
2329                         }
2330                         /*
2331                          * skb was dropped but not destructed yet;
2332                          * let's treat it like congestion or err < 0
2333                          */
2334                         err = 0;
2335                 }
2336                 packet_increment_head(&po->tx_ring);
2337                 len_sum += tp_len;
2338         } while (likely((ph != NULL) ||
2339                 /* Note: packet_read_pending() might be slow if we have
2340                  * to call it as it's per_cpu variable, but in fast-path
2341                  * we already short-circuit the loop with the first
2342                  * condition, and luckily don't have to go that path
2343                  * anyway.
2344                  */
2345                  (need_wait && packet_read_pending(&po->tx_ring))));
2346
2347         err = len_sum;
2348         goto out_put;
2349
2350 out_status:
2351         __packet_set_status(po, ph, status);
2352         kfree_skb(skb);
2353 out_put:
2354         dev_put(dev);
2355 out:
2356         mutex_unlock(&po->pg_vec_lock);
2357         return err;
2358 }
2359
2360 static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
2361                                         size_t reserve, size_t len,
2362                                         size_t linear, int noblock,
2363                                         int *err)
2364 {
2365         struct sk_buff *skb;
2366
2367         /* Under a page?  Don't bother with paged skb. */
2368         if (prepad + len < PAGE_SIZE || !linear)
2369                 linear = len;
2370
2371         skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
2372                                    err, 0);
2373         if (!skb)
2374                 return NULL;
2375
2376         skb_reserve(skb, reserve);
2377         skb_put(skb, linear);
2378         skb->data_len = len - linear;
2379         skb->len += len - linear;
2380
2381         return skb;
2382 }
2383
2384 static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
2385 {
2386         struct sock *sk = sock->sk;
2387         DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2388         struct sk_buff *skb;
2389         struct net_device *dev;
2390         __be16 proto;
2391         unsigned char *addr;
2392         int err, reserve = 0;
2393         struct virtio_net_hdr vnet_hdr = { 0 };
2394         int offset = 0;
2395         int vnet_hdr_len;
2396         struct packet_sock *po = pkt_sk(sk);
2397         unsigned short gso_type = 0;
2398         int hlen, tlen;
2399         int extra_len = 0;
2400
2401         /*
2402          *      Get and verify the address.
2403          */
2404
2405         if (likely(saddr == NULL)) {
2406                 dev     = packet_cached_dev_get(po);
2407                 proto   = po->num;
2408                 addr    = NULL;
2409         } else {
2410                 err = -EINVAL;
2411                 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2412                         goto out;
2413                 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
2414                         goto out;
2415                 proto   = saddr->sll_protocol;
2416                 addr    = saddr->sll_addr;
2417                 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
2418         }
2419
2420         err = -ENXIO;
2421         if (unlikely(dev == NULL))
2422                 goto out_unlock;
2423         err = -ENETDOWN;
2424         if (unlikely(!(dev->flags & IFF_UP)))
2425                 goto out_unlock;
2426
2427         if (sock->type == SOCK_RAW)
2428                 reserve = dev->hard_header_len;
2429         if (po->has_vnet_hdr) {
2430                 vnet_hdr_len = sizeof(vnet_hdr);
2431
2432                 err = -EINVAL;
2433                 if (len < vnet_hdr_len)
2434                         goto out_unlock;
2435
2436                 len -= vnet_hdr_len;
2437
2438                 err = memcpy_fromiovec((void *)&vnet_hdr, msg->msg_iov,
2439                                        vnet_hdr_len);
2440                 if (err < 0)
2441                         goto out_unlock;
2442
2443                 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
2444                     (vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 >
2445                       vnet_hdr.hdr_len))
2446                         vnet_hdr.hdr_len = vnet_hdr.csum_start +
2447                                                  vnet_hdr.csum_offset + 2;
2448
2449                 err = -EINVAL;
2450                 if (vnet_hdr.hdr_len > len)
2451                         goto out_unlock;
2452
2453                 if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
2454                         switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
2455                         case VIRTIO_NET_HDR_GSO_TCPV4:
2456                                 gso_type = SKB_GSO_TCPV4;
2457                                 break;
2458                         case VIRTIO_NET_HDR_GSO_TCPV6:
2459                                 gso_type = SKB_GSO_TCPV6;
2460                                 break;
2461                         case VIRTIO_NET_HDR_GSO_UDP:
2462                                 gso_type = SKB_GSO_UDP;
2463                                 break;
2464                         default:
2465                                 goto out_unlock;
2466                         }
2467
2468                         if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
2469                                 gso_type |= SKB_GSO_TCP_ECN;
2470
2471                         if (vnet_hdr.gso_size == 0)
2472                                 goto out_unlock;
2473
2474                 }
2475         }
2476
2477         if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
2478                 if (!netif_supports_nofcs(dev)) {
2479                         err = -EPROTONOSUPPORT;
2480                         goto out_unlock;
2481                 }
2482                 extra_len = 4; /* We're doing our own CRC */
2483         }
2484
2485         err = -EMSGSIZE;
2486         if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN + extra_len))
2487                 goto out_unlock;
2488
2489         err = -ENOBUFS;
2490         hlen = LL_RESERVED_SPACE(dev);
2491         tlen = dev->needed_tailroom;
2492         skb = packet_alloc_skb(sk, hlen + tlen, hlen, len, vnet_hdr.hdr_len,
2493                                msg->msg_flags & MSG_DONTWAIT, &err);
2494         if (skb == NULL)
2495                 goto out_unlock;
2496
2497         skb_set_network_header(skb, reserve);
2498
2499         err = -EINVAL;
2500         if (sock->type == SOCK_DGRAM &&
2501             (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0)
2502                 goto out_free;
2503
2504         /* Returns -EFAULT on error */
2505         err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len);
2506         if (err)
2507                 goto out_free;
2508
2509         sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
2510
2511         if (!gso_type && (len > dev->mtu + reserve + extra_len)) {
2512                 /* Earlier code assumed this would be a VLAN pkt,
2513                  * double-check this now that we have the actual
2514                  * packet in hand.
2515                  */
2516                 struct ethhdr *ehdr;
2517                 skb_reset_mac_header(skb);
2518                 ehdr = eth_hdr(skb);
2519                 if (ehdr->h_proto != htons(ETH_P_8021Q)) {
2520                         err = -EMSGSIZE;
2521                         goto out_free;
2522                 }
2523         }
2524
2525         skb->protocol = proto;
2526         skb->dev = dev;
2527         skb->priority = sk->sk_priority;
2528         skb->mark = sk->sk_mark;
2529
2530         packet_pick_tx_queue(dev, skb);
2531
2532         if (po->has_vnet_hdr) {
2533                 if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
2534                         if (!skb_partial_csum_set(skb, vnet_hdr.csum_start,
2535                                                   vnet_hdr.csum_offset)) {
2536                                 err = -EINVAL;
2537                                 goto out_free;
2538                         }
2539                 }
2540
2541                 skb_shinfo(skb)->gso_size = vnet_hdr.gso_size;
2542                 skb_shinfo(skb)->gso_type = gso_type;
2543
2544                 /* Header must be checked, and gso_segs computed. */
2545                 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2546                 skb_shinfo(skb)->gso_segs = 0;
2547
2548                 len += vnet_hdr_len;
2549         }
2550
2551         if (!packet_use_direct_xmit(po))
2552                 skb_probe_transport_header(skb, reserve);
2553         if (unlikely(extra_len == 4))
2554                 skb->no_fcs = 1;
2555
2556         err = po->xmit(skb);
2557         if (err > 0 && (err = net_xmit_errno(err)) != 0)
2558                 goto out_unlock;
2559
2560         dev_put(dev);
2561
2562         return len;
2563
2564 out_free:
2565         kfree_skb(skb);
2566 out_unlock:
2567         if (dev)
2568                 dev_put(dev);
2569 out:
2570         return err;
2571 }
2572
2573 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
2574                 struct msghdr *msg, size_t len)
2575 {
2576         struct sock *sk = sock->sk;
2577         struct packet_sock *po = pkt_sk(sk);
2578
2579         if (po->tx_ring.pg_vec)
2580                 return tpacket_snd(po, msg);
2581         else
2582                 return packet_snd(sock, msg, len);
2583 }
2584
2585 /*
2586  *      Close a PACKET socket. This is fairly simple. We immediately go
2587  *      to 'closed' state and remove our protocol entry in the device list.
2588  */
2589
2590 static int packet_release(struct socket *sock)
2591 {
2592         struct sock *sk = sock->sk;
2593         struct packet_sock *po;
2594         struct net *net;
2595         union tpacket_req_u req_u;
2596
2597         if (!sk)
2598                 return 0;
2599
2600         net = sock_net(sk);
2601         po = pkt_sk(sk);
2602
2603         mutex_lock(&net->packet.sklist_lock);
2604         sk_del_node_init_rcu(sk);
2605         mutex_unlock(&net->packet.sklist_lock);
2606
2607         preempt_disable();
2608         sock_prot_inuse_add(net, sk->sk_prot, -1);
2609         preempt_enable();
2610
2611         spin_lock(&po->bind_lock);
2612         unregister_prot_hook(sk, false);
2613         packet_cached_dev_reset(po);
2614
2615         if (po->prot_hook.dev) {
2616                 dev_put(po->prot_hook.dev);
2617                 po->prot_hook.dev = NULL;
2618         }
2619         spin_unlock(&po->bind_lock);
2620
2621         packet_flush_mclist(sk);
2622
2623         if (po->rx_ring.pg_vec) {
2624                 memset(&req_u, 0, sizeof(req_u));
2625                 packet_set_ring(sk, &req_u, 1, 0);
2626         }
2627
2628         if (po->tx_ring.pg_vec) {
2629                 memset(&req_u, 0, sizeof(req_u));
2630                 packet_set_ring(sk, &req_u, 1, 1);
2631         }
2632
2633         fanout_release(sk);
2634
2635         synchronize_net();
2636         /*
2637          *      Now the socket is dead. No more input will appear.
2638          */
2639         sock_orphan(sk);
2640         sock->sk = NULL;
2641
2642         /* Purge queues */
2643
2644         skb_queue_purge(&sk->sk_receive_queue);
2645         packet_free_pending(po);
2646         sk_refcnt_debug_release(sk);
2647
2648         sock_put(sk);
2649         return 0;
2650 }
2651
2652 /*
2653  *      Attach a packet hook.
2654  */
2655
2656 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 proto)
2657 {
2658         struct packet_sock *po = pkt_sk(sk);
2659         const struct net_device *dev_curr;
2660         __be16 proto_curr;
2661         bool need_rehook;
2662
2663         if (po->fanout) {
2664                 if (dev)
2665                         dev_put(dev);
2666
2667                 return -EINVAL;
2668         }
2669
2670         lock_sock(sk);
2671         spin_lock(&po->bind_lock);
2672
2673         proto_curr = po->prot_hook.type;
2674         dev_curr = po->prot_hook.dev;
2675
2676         need_rehook = proto_curr != proto || dev_curr != dev;
2677
2678         if (need_rehook) {
2679                 unregister_prot_hook(sk, true);
2680
2681                 po->num = proto;
2682                 po->prot_hook.type = proto;
2683
2684                 if (po->prot_hook.dev)
2685                         dev_put(po->prot_hook.dev);
2686
2687                 po->prot_hook.dev = dev;
2688
2689                 po->ifindex = dev ? dev->ifindex : 0;
2690                 packet_cached_dev_assign(po, dev);
2691         }
2692
2693         if (proto == 0 || !need_rehook)
2694                 goto out_unlock;
2695
2696         if (!dev || (dev->flags & IFF_UP)) {
2697                 register_prot_hook(sk);
2698         } else {
2699                 sk->sk_err = ENETDOWN;
2700                 if (!sock_flag(sk, SOCK_DEAD))
2701                         sk->sk_error_report(sk);
2702         }
2703
2704 out_unlock:
2705         spin_unlock(&po->bind_lock);
2706         release_sock(sk);
2707         return 0;
2708 }
2709
2710 /*
2711  *      Bind a packet socket to a device
2712  */
2713
2714 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
2715                             int addr_len)
2716 {
2717         struct sock *sk = sock->sk;
2718         char name[15];
2719         struct net_device *dev;
2720         int err = -ENODEV;
2721
2722         /*
2723          *      Check legality
2724          */
2725
2726         if (addr_len != sizeof(struct sockaddr))
2727                 return -EINVAL;
2728         strlcpy(name, uaddr->sa_data, sizeof(name));
2729
2730         dev = dev_get_by_name(sock_net(sk), name);
2731         if (dev)
2732                 err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
2733         return err;
2734 }
2735
2736 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
2737 {
2738         struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
2739         struct sock *sk = sock->sk;
2740         struct net_device *dev = NULL;
2741         int err;
2742
2743
2744         /*
2745          *      Check legality
2746          */
2747
2748         if (addr_len < sizeof(struct sockaddr_ll))
2749                 return -EINVAL;
2750         if (sll->sll_family != AF_PACKET)
2751                 return -EINVAL;
2752
2753         if (sll->sll_ifindex) {
2754                 err = -ENODEV;
2755                 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
2756                 if (dev == NULL)
2757                         goto out;
2758         }
2759         err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
2760
2761 out:
2762         return err;
2763 }
2764
2765 static struct proto packet_proto = {
2766         .name     = "PACKET",
2767         .owner    = THIS_MODULE,
2768         .obj_size = sizeof(struct packet_sock),
2769 };
2770
2771 /*
2772  *      Create a packet of type SOCK_PACKET.
2773  */
2774
2775 static int packet_create(struct net *net, struct socket *sock, int protocol,
2776                          int kern)
2777 {
2778         struct sock *sk;
2779         struct packet_sock *po;
2780         __be16 proto = (__force __be16)protocol; /* weird, but documented */
2781         int err;
2782
2783         if (!ns_capable(net->user_ns, CAP_NET_RAW))
2784                 return -EPERM;
2785         if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
2786             sock->type != SOCK_PACKET)
2787                 return -ESOCKTNOSUPPORT;
2788
2789         sock->state = SS_UNCONNECTED;
2790
2791         err = -ENOBUFS;
2792         sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
2793         if (sk == NULL)
2794                 goto out;
2795
2796         sock->ops = &packet_ops;
2797         if (sock->type == SOCK_PACKET)
2798                 sock->ops = &packet_ops_spkt;
2799
2800         sock_init_data(sock, sk);
2801
2802         po = pkt_sk(sk);
2803         sk->sk_family = PF_PACKET;
2804         po->num = proto;
2805         po->xmit = dev_queue_xmit;
2806
2807         err = packet_alloc_pending(po);
2808         if (err)
2809                 goto out2;
2810
2811         packet_cached_dev_reset(po);
2812
2813         sk->sk_destruct = packet_sock_destruct;
2814         sk_refcnt_debug_inc(sk);
2815
2816         /*
2817          *      Attach a protocol block
2818          */
2819
2820         spin_lock_init(&po->bind_lock);
2821         mutex_init(&po->pg_vec_lock);
2822         po->prot_hook.func = packet_rcv;
2823
2824         if (sock->type == SOCK_PACKET)
2825                 po->prot_hook.func = packet_rcv_spkt;
2826
2827         po->prot_hook.af_packet_priv = sk;
2828
2829         if (proto) {
2830                 po->prot_hook.type = proto;
2831                 register_prot_hook(sk);
2832         }
2833
2834         mutex_lock(&net->packet.sklist_lock);
2835         sk_add_node_rcu(sk, &net->packet.sklist);
2836         mutex_unlock(&net->packet.sklist_lock);
2837
2838         preempt_disable();
2839         sock_prot_inuse_add(net, &packet_proto, 1);
2840         preempt_enable();
2841
2842         return 0;
2843 out2:
2844         sk_free(sk);
2845 out:
2846         return err;
2847 }
2848
2849 /*
2850  *      Pull a packet from our receive queue and hand it to the user.
2851  *      If necessary we block.
2852  */
2853
2854 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
2855                           struct msghdr *msg, size_t len, int flags)
2856 {
2857         struct sock *sk = sock->sk;
2858         struct sk_buff *skb;
2859         int copied, err;
2860         int vnet_hdr_len = 0;
2861
2862         err = -EINVAL;
2863         if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
2864                 goto out;
2865
2866 #if 0
2867         /* What error should we return now? EUNATTACH? */
2868         if (pkt_sk(sk)->ifindex < 0)
2869                 return -ENODEV;
2870 #endif
2871
2872         if (flags & MSG_ERRQUEUE) {
2873                 err = sock_recv_errqueue(sk, msg, len,
2874                                          SOL_PACKET, PACKET_TX_TIMESTAMP);
2875                 goto out;
2876         }
2877
2878         /*
2879          *      Call the generic datagram receiver. This handles all sorts
2880          *      of horrible races and re-entrancy so we can forget about it
2881          *      in the protocol layers.
2882          *
2883          *      Now it will return ENETDOWN, if device have just gone down,
2884          *      but then it will block.
2885          */
2886
2887         skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
2888
2889         /*
2890          *      An error occurred so return it. Because skb_recv_datagram()
2891          *      handles the blocking we don't see and worry about blocking
2892          *      retries.
2893          */
2894
2895         if (skb == NULL)
2896                 goto out;
2897
2898         if (pkt_sk(sk)->has_vnet_hdr) {
2899                 struct virtio_net_hdr vnet_hdr = { 0 };
2900
2901                 err = -EINVAL;
2902                 vnet_hdr_len = sizeof(vnet_hdr);
2903                 if (len < vnet_hdr_len)
2904                         goto out_free;
2905
2906                 len -= vnet_hdr_len;
2907
2908                 if (skb_is_gso(skb)) {
2909                         struct skb_shared_info *sinfo = skb_shinfo(skb);
2910
2911                         /* This is a hint as to how much should be linear. */
2912                         vnet_hdr.hdr_len = skb_headlen(skb);
2913                         vnet_hdr.gso_size = sinfo->gso_size;
2914                         if (sinfo->gso_type & SKB_GSO_TCPV4)
2915                                 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
2916                         else if (sinfo->gso_type & SKB_GSO_TCPV6)
2917                                 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
2918                         else if (sinfo->gso_type & SKB_GSO_UDP)
2919                                 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
2920                         else if (sinfo->gso_type & SKB_GSO_FCOE)
2921                                 goto out_free;
2922                         else
2923                                 BUG();
2924                         if (sinfo->gso_type & SKB_GSO_TCP_ECN)
2925                                 vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
2926                 } else
2927                         vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
2928
2929                 if (skb->ip_summed == CHECKSUM_PARTIAL) {
2930                         vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
2931                         vnet_hdr.csum_start = skb_checksum_start_offset(skb);
2932                         vnet_hdr.csum_offset = skb->csum_offset;
2933                 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
2934                         vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID;
2935                 } /* else everything is zero */
2936
2937                 err = memcpy_toiovec(msg->msg_iov, (void *)&vnet_hdr,
2938                                      vnet_hdr_len);
2939                 if (err < 0)
2940                         goto out_free;
2941         }
2942
2943         /* You lose any data beyond the buffer you gave. If it worries
2944          * a user program they can ask the device for its MTU
2945          * anyway.
2946          */
2947         copied = skb->len;
2948         if (copied > len) {
2949                 copied = len;
2950                 msg->msg_flags |= MSG_TRUNC;
2951         }
2952
2953         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
2954         if (err)
2955                 goto out_free;
2956
2957         sock_recv_ts_and_drops(msg, sk, skb);
2958
2959         if (msg->msg_name) {
2960                 /* If the address length field is there to be filled
2961                  * in, we fill it in now.
2962                  */
2963                 if (sock->type == SOCK_PACKET) {
2964                         __sockaddr_check_size(sizeof(struct sockaddr_pkt));
2965                         msg->msg_namelen = sizeof(struct sockaddr_pkt);
2966                 } else {
2967                         struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
2968                         msg->msg_namelen = sll->sll_halen +
2969                                 offsetof(struct sockaddr_ll, sll_addr);
2970                 }
2971                 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
2972                        msg->msg_namelen);
2973         }
2974
2975         if (pkt_sk(sk)->auxdata) {
2976                 struct tpacket_auxdata aux;
2977
2978                 aux.tp_status = TP_STATUS_USER;
2979                 if (skb->ip_summed == CHECKSUM_PARTIAL)
2980                         aux.tp_status |= TP_STATUS_CSUMNOTREADY;
2981                 aux.tp_len = PACKET_SKB_CB(skb)->origlen;
2982                 aux.tp_snaplen = skb->len;
2983                 aux.tp_mac = 0;
2984                 aux.tp_net = skb_network_offset(skb);
2985                 if (vlan_tx_tag_present(skb)) {
2986                         aux.tp_vlan_tci = vlan_tx_tag_get(skb);
2987                         aux.tp_vlan_tpid = ntohs(skb->vlan_proto);
2988                         aux.tp_status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
2989                 } else {
2990                         aux.tp_vlan_tci = 0;
2991                         aux.tp_vlan_tpid = 0;
2992                 }
2993                 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
2994         }
2995
2996         /*
2997          *      Free or return the buffer as appropriate. Again this
2998          *      hides all the races and re-entrancy issues from us.
2999          */
3000         err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
3001
3002 out_free:
3003         skb_free_datagram(sk, skb);
3004 out:
3005         return err;
3006 }
3007
3008 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
3009                                int *uaddr_len, int peer)
3010 {
3011         struct net_device *dev;
3012         struct sock *sk = sock->sk;
3013
3014         if (peer)
3015                 return -EOPNOTSUPP;
3016
3017         uaddr->sa_family = AF_PACKET;
3018         memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data));
3019         rcu_read_lock();
3020         dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
3021         if (dev)
3022                 strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data));
3023         rcu_read_unlock();
3024         *uaddr_len = sizeof(*uaddr);
3025
3026         return 0;
3027 }
3028
3029 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
3030                           int *uaddr_len, int peer)
3031 {
3032         struct net_device *dev;
3033         struct sock *sk = sock->sk;
3034         struct packet_sock *po = pkt_sk(sk);
3035         DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
3036
3037         if (peer)
3038                 return -EOPNOTSUPP;
3039
3040         sll->sll_family = AF_PACKET;
3041         sll->sll_ifindex = po->ifindex;
3042         sll->sll_protocol = po->num;
3043         sll->sll_pkttype = 0;
3044         rcu_read_lock();
3045         dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
3046         if (dev) {
3047                 sll->sll_hatype = dev->type;
3048                 sll->sll_halen = dev->addr_len;
3049                 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
3050         } else {
3051                 sll->sll_hatype = 0;    /* Bad: we have no ARPHRD_UNSPEC */
3052                 sll->sll_halen = 0;
3053         }
3054         rcu_read_unlock();
3055         *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
3056
3057         return 0;
3058 }
3059
3060 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
3061                          int what)
3062 {
3063         switch (i->type) {
3064         case PACKET_MR_MULTICAST:
3065                 if (i->alen != dev->addr_len)
3066                         return -EINVAL;
3067                 if (what > 0)
3068                         return dev_mc_add(dev, i->addr);
3069                 else
3070                         return dev_mc_del(dev, i->addr);
3071                 break;
3072         case PACKET_MR_PROMISC:
3073                 return dev_set_promiscuity(dev, what);
3074                 break;
3075         case PACKET_MR_ALLMULTI:
3076                 return dev_set_allmulti(dev, what);
3077                 break;
3078         case PACKET_MR_UNICAST:
3079                 if (i->alen != dev->addr_len)
3080                         return -EINVAL;
3081                 if (what > 0)
3082                         return dev_uc_add(dev, i->addr);
3083                 else
3084                         return dev_uc_del(dev, i->addr);
3085                 break;
3086         default:
3087                 break;
3088         }
3089         return 0;
3090 }
3091
3092 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
3093 {
3094         for ( ; i; i = i->next) {
3095                 if (i->ifindex == dev->ifindex)
3096                         packet_dev_mc(dev, i, what);
3097         }
3098 }
3099
3100 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
3101 {
3102         struct packet_sock *po = pkt_sk(sk);
3103         struct packet_mclist *ml, *i;
3104         struct net_device *dev;
3105         int err;
3106
3107         rtnl_lock();
3108
3109         err = -ENODEV;
3110         dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
3111         if (!dev)
3112                 goto done;
3113
3114         err = -EINVAL;
3115         if (mreq->mr_alen > dev->addr_len)
3116                 goto done;
3117
3118         err = -ENOBUFS;
3119         i = kmalloc(sizeof(*i), GFP_KERNEL);
3120         if (i == NULL)
3121                 goto done;
3122
3123         err = 0;
3124         for (ml = po->mclist; ml; ml = ml->next) {
3125                 if (ml->ifindex == mreq->mr_ifindex &&
3126                     ml->type == mreq->mr_type &&
3127                     ml->alen == mreq->mr_alen &&
3128                     memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3129                         ml->count++;
3130                         /* Free the new element ... */
3131                         kfree(i);
3132                         goto done;
3133                 }
3134         }
3135
3136         i->type = mreq->mr_type;
3137         i->ifindex = mreq->mr_ifindex;
3138         i->alen = mreq->mr_alen;
3139         memcpy(i->addr, mreq->mr_address, i->alen);
3140         i->count = 1;
3141         i->next = po->mclist;
3142         po->mclist = i;
3143         err = packet_dev_mc(dev, i, 1);
3144         if (err) {
3145                 po->mclist = i->next;
3146                 kfree(i);
3147         }
3148
3149 done:
3150         rtnl_unlock();
3151         return err;
3152 }
3153
3154 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
3155 {
3156         struct packet_mclist *ml, **mlp;
3157
3158         rtnl_lock();
3159
3160         for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
3161                 if (ml->ifindex == mreq->mr_ifindex &&
3162                     ml->type == mreq->mr_type &&
3163                     ml->alen == mreq->mr_alen &&
3164                     memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3165                         if (--ml->count == 0) {
3166                                 struct net_device *dev;
3167                                 *mlp = ml->next;
3168                                 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3169                                 if (dev)
3170                                         packet_dev_mc(dev, ml, -1);
3171                                 kfree(ml);
3172                         }
3173                         rtnl_unlock();
3174                         return 0;
3175                 }
3176         }
3177         rtnl_unlock();
3178         return -EADDRNOTAVAIL;
3179 }
3180
3181 static void packet_flush_mclist(struct sock *sk)
3182 {
3183         struct packet_sock *po = pkt_sk(sk);
3184         struct packet_mclist *ml;
3185
3186         if (!po->mclist)
3187                 return;
3188
3189         rtnl_lock();
3190         while ((ml = po->mclist) != NULL) {
3191                 struct net_device *dev;
3192
3193                 po->mclist = ml->next;
3194                 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3195                 if (dev != NULL)
3196                         packet_dev_mc(dev, ml, -1);
3197                 kfree(ml);
3198         }
3199         rtnl_unlock();
3200 }
3201
3202 static int
3203 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
3204 {
3205         struct sock *sk = sock->sk;
3206         struct packet_sock *po = pkt_sk(sk);
3207         int ret;
3208
3209         if (level != SOL_PACKET)
3210                 return -ENOPROTOOPT;
3211
3212         switch (optname) {
3213         case PACKET_ADD_MEMBERSHIP:
3214         case PACKET_DROP_MEMBERSHIP:
3215         {
3216                 struct packet_mreq_max mreq;
3217                 int len = optlen;
3218                 memset(&mreq, 0, sizeof(mreq));
3219                 if (len < sizeof(struct packet_mreq))
3220                         return -EINVAL;
3221                 if (len > sizeof(mreq))
3222                         len = sizeof(mreq);
3223                 if (copy_from_user(&mreq, optval, len))
3224                         return -EFAULT;
3225                 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
3226                         return -EINVAL;
3227                 if (optname == PACKET_ADD_MEMBERSHIP)
3228                         ret = packet_mc_add(sk, &mreq);
3229                 else
3230                         ret = packet_mc_drop(sk, &mreq);
3231                 return ret;
3232         }
3233
3234         case PACKET_RX_RING:
3235         case PACKET_TX_RING:
3236         {
3237                 union tpacket_req_u req_u;
3238                 int len;
3239
3240                 switch (po->tp_version) {
3241                 case TPACKET_V1:
3242                 case TPACKET_V2:
3243                         len = sizeof(req_u.req);
3244                         break;
3245                 case TPACKET_V3:
3246                 default:
3247                         len = sizeof(req_u.req3);
3248                         break;
3249                 }
3250                 if (optlen < len)
3251                         return -EINVAL;
3252                 if (pkt_sk(sk)->has_vnet_hdr)
3253                         return -EINVAL;
3254                 if (copy_from_user(&req_u.req, optval, len))
3255                         return -EFAULT;
3256                 return packet_set_ring(sk, &req_u, 0,
3257                         optname == PACKET_TX_RING);
3258         }
3259         case PACKET_COPY_THRESH:
3260         {
3261                 int val;
3262
3263                 if (optlen != sizeof(val))
3264                         return -EINVAL;
3265                 if (copy_from_user(&val, optval, sizeof(val)))
3266                         return -EFAULT;
3267
3268                 pkt_sk(sk)->copy_thresh = val;
3269                 return 0;
3270         }
3271         case PACKET_VERSION:
3272         {
3273                 int val;
3274
3275                 if (optlen != sizeof(val))
3276                         return -EINVAL;
3277                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3278                         return -EBUSY;
3279                 if (copy_from_user(&val, optval, sizeof(val)))
3280                         return -EFAULT;
3281                 switch (val) {
3282                 case TPACKET_V1:
3283                 case TPACKET_V2:
3284                 case TPACKET_V3:
3285                         po->tp_version = val;
3286                         return 0;
3287                 default:
3288                         return -EINVAL;
3289                 }
3290         }
3291         case PACKET_RESERVE:
3292         {
3293                 unsigned int val;
3294
3295                 if (optlen != sizeof(val))
3296                         return -EINVAL;
3297                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3298                         return -EBUSY;
3299                 if (copy_from_user(&val, optval, sizeof(val)))
3300                         return -EFAULT;
3301                 po->tp_reserve = val;
3302                 return 0;
3303         }
3304         case PACKET_LOSS:
3305         {
3306                 unsigned int val;
3307
3308                 if (optlen != sizeof(val))
3309                         return -EINVAL;
3310                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3311                         return -EBUSY;
3312                 if (copy_from_user(&val, optval, sizeof(val)))
3313                         return -EFAULT;
3314                 po->tp_loss = !!val;
3315                 return 0;
3316         }
3317         case PACKET_AUXDATA:
3318         {
3319                 int val;
3320
3321                 if (optlen < sizeof(val))
3322                         return -EINVAL;
3323                 if (copy_from_user(&val, optval, sizeof(val)))
3324                         return -EFAULT;
3325
3326                 po->auxdata = !!val;
3327                 return 0;
3328         }
3329         case PACKET_ORIGDEV:
3330         {
3331                 int val;
3332
3333                 if (optlen < sizeof(val))
3334                         return -EINVAL;
3335                 if (copy_from_user(&val, optval, sizeof(val)))
3336                         return -EFAULT;
3337
3338                 po->origdev = !!val;
3339                 return 0;
3340         }
3341         case PACKET_VNET_HDR:
3342         {
3343                 int val;
3344
3345                 if (sock->type != SOCK_RAW)
3346                         return -EINVAL;
3347                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3348                         return -EBUSY;
3349                 if (optlen < sizeof(val))
3350                         return -EINVAL;
3351                 if (copy_from_user(&val, optval, sizeof(val)))
3352                         return -EFAULT;
3353
3354                 po->has_vnet_hdr = !!val;
3355                 return 0;
3356         }
3357         case PACKET_TIMESTAMP:
3358         {
3359                 int val;
3360
3361                 if (optlen != sizeof(val))
3362                         return -EINVAL;
3363                 if (copy_from_user(&val, optval, sizeof(val)))
3364                         return -EFAULT;
3365
3366                 po->tp_tstamp = val;
3367                 return 0;
3368         }
3369         case PACKET_FANOUT:
3370         {
3371                 int val;
3372
3373                 if (optlen != sizeof(val))
3374                         return -EINVAL;
3375                 if (copy_from_user(&val, optval, sizeof(val)))
3376                         return -EFAULT;
3377
3378                 return fanout_add(sk, val & 0xffff, val >> 16);
3379         }
3380         case PACKET_TX_HAS_OFF:
3381         {
3382                 unsigned int val;
3383
3384                 if (optlen != sizeof(val))
3385                         return -EINVAL;
3386                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
3387                         return -EBUSY;
3388                 if (copy_from_user(&val, optval, sizeof(val)))
3389                         return -EFAULT;
3390                 po->tp_tx_has_off = !!val;
3391                 return 0;
3392         }
3393         case PACKET_QDISC_BYPASS:
3394         {
3395                 int val;
3396
3397                 if (optlen != sizeof(val))
3398                         return -EINVAL;
3399                 if (copy_from_user(&val, optval, sizeof(val)))
3400                         return -EFAULT;
3401
3402                 po->xmit = val ? packet_direct_xmit : dev_queue_xmit;
3403                 return 0;
3404         }
3405         default:
3406                 return -ENOPROTOOPT;
3407         }
3408 }
3409
3410 static int packet_getsockopt(struct socket *sock, int level, int optname,
3411                              char __user *optval, int __user *optlen)
3412 {
3413         int len;
3414         int val, lv = sizeof(val);
3415         struct sock *sk = sock->sk;
3416         struct packet_sock *po = pkt_sk(sk);
3417         void *data = &val;
3418         union tpacket_stats_u st;
3419
3420         if (level != SOL_PACKET)
3421                 return -ENOPROTOOPT;
3422
3423         if (get_user(len, optlen))
3424                 return -EFAULT;
3425
3426         if (len < 0)
3427                 return -EINVAL;
3428
3429         switch (optname) {
3430         case PACKET_STATISTICS:
3431                 spin_lock_bh(&sk->sk_receive_queue.lock);
3432                 memcpy(&st, &po->stats, sizeof(st));
3433                 memset(&po->stats, 0, sizeof(po->stats));
3434                 spin_unlock_bh(&sk->sk_receive_queue.lock);
3435
3436                 if (po->tp_version == TPACKET_V3) {
3437                         lv = sizeof(struct tpacket_stats_v3);
3438                         st.stats3.tp_packets += st.stats3.tp_drops;
3439                         data = &st.stats3;
3440                 } else {
3441                         lv = sizeof(struct tpacket_stats);
3442                         st.stats1.tp_packets += st.stats1.tp_drops;
3443                         data = &st.stats1;
3444                 }
3445
3446                 break;
3447         case PACKET_AUXDATA:
3448                 val = po->auxdata;
3449                 break;
3450         case PACKET_ORIGDEV:
3451                 val = po->origdev;
3452                 break;
3453         case PACKET_VNET_HDR:
3454                 val = po->has_vnet_hdr;
3455                 break;
3456         case PACKET_VERSION:
3457                 val = po->tp_version;
3458                 break;
3459         case PACKET_HDRLEN:
3460                 if (len > sizeof(int))
3461                         len = sizeof(int);
3462                 if (copy_from_user(&val, optval, len))
3463                         return -EFAULT;
3464                 switch (val) {
3465                 case TPACKET_V1:
3466                         val = sizeof(struct tpacket_hdr);
3467                         break;
3468                 case TPACKET_V2:
3469                         val = sizeof(struct tpacket2_hdr);
3470                         break;
3471                 case TPACKET_V3:
3472                         val = sizeof(struct tpacket3_hdr);
3473                         break;
3474                 default:
3475                         return -EINVAL;
3476                 }
3477                 break;
3478         case PACKET_RESERVE:
3479                 val = po->tp_reserve;
3480                 break;
3481         case PACKET_LOSS:
3482                 val = po->tp_loss;
3483                 break;
3484         case PACKET_TIMESTAMP:
3485                 val = po->tp_tstamp;
3486                 break;
3487         case PACKET_FANOUT:
3488                 val = (po->fanout ?
3489                        ((u32)po->fanout->id |
3490                         ((u32)po->fanout->type << 16) |
3491                         ((u32)po->fanout->flags << 24)) :
3492                        0);
3493                 break;
3494         case PACKET_TX_HAS_OFF:
3495                 val = po->tp_tx_has_off;
3496                 break;
3497         case PACKET_QDISC_BYPASS:
3498                 val = packet_use_direct_xmit(po);
3499                 break;
3500         default:
3501                 return -ENOPROTOOPT;
3502         }
3503
3504         if (len > lv)
3505                 len = lv;
3506         if (put_user(len, optlen))
3507                 return -EFAULT;
3508         if (copy_to_user(optval, data, len))
3509                 return -EFAULT;
3510         return 0;
3511 }
3512
3513
3514 static int packet_notifier(struct notifier_block *this,
3515                            unsigned long msg, void *ptr)
3516 {
3517         struct sock *sk;
3518         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3519         struct net *net = dev_net(dev);
3520
3521         rcu_read_lock();
3522         sk_for_each_rcu(sk, &net->packet.sklist) {
3523                 struct packet_sock *po = pkt_sk(sk);
3524
3525                 switch (msg) {
3526                 case NETDEV_UNREGISTER:
3527                         if (po->mclist)
3528                                 packet_dev_mclist(dev, po->mclist, -1);
3529                         /* fallthrough */
3530
3531                 case NETDEV_DOWN:
3532                         if (dev->ifindex == po->ifindex) {
3533                                 spin_lock(&po->bind_lock);
3534                                 if (po->running) {
3535                                         __unregister_prot_hook(sk, false);
3536                                         sk->sk_err = ENETDOWN;
3537                                         if (!sock_flag(sk, SOCK_DEAD))
3538                                                 sk->sk_error_report(sk);
3539                                 }
3540                                 if (msg == NETDEV_UNREGISTER) {
3541                                         packet_cached_dev_reset(po);
3542                                         po->ifindex = -1;
3543                                         if (po->prot_hook.dev)
3544                                                 dev_put(po->prot_hook.dev);
3545                                         po->prot_hook.dev = NULL;
3546                                 }
3547                                 spin_unlock(&po->bind_lock);
3548                         }
3549                         break;
3550                 case NETDEV_UP:
3551                         if (dev->ifindex == po->ifindex) {
3552                                 spin_lock(&po->bind_lock);
3553                                 if (po->num)
3554                                         register_prot_hook(sk);
3555                                 spin_unlock(&po->bind_lock);
3556                         }
3557                         break;
3558                 }
3559         }
3560         rcu_read_unlock();
3561         return NOTIFY_DONE;
3562 }
3563
3564
3565 static int packet_ioctl(struct socket *sock, unsigned int cmd,
3566                         unsigned long arg)
3567 {
3568         struct sock *sk = sock->sk;
3569
3570         switch (cmd) {
3571         case SIOCOUTQ:
3572         {
3573                 int amount = sk_wmem_alloc_get(sk);
3574
3575                 return put_user(amount, (int __user *)arg);
3576         }
3577         case SIOCINQ:
3578         {
3579                 struct sk_buff *skb;
3580                 int amount = 0;
3581
3582                 spin_lock_bh(&sk->sk_receive_queue.lock);
3583                 skb = skb_peek(&sk->sk_receive_queue);
3584                 if (skb)
3585                         amount = skb->len;
3586                 spin_unlock_bh(&sk->sk_receive_queue.lock);
3587                 return put_user(amount, (int __user *)arg);
3588         }
3589         case SIOCGSTAMP:
3590                 return sock_get_timestamp(sk, (struct timeval __user *)arg);
3591         case SIOCGSTAMPNS:
3592                 return sock_get_timestampns(sk, (struct timespec __user *)arg);
3593
3594 #ifdef CONFIG_INET
3595         case SIOCADDRT:
3596         case SIOCDELRT:
3597         case SIOCDARP:
3598         case SIOCGARP:
3599         case SIOCSARP:
3600         case SIOCGIFADDR:
3601         case SIOCSIFADDR:
3602         case SIOCGIFBRDADDR:
3603         case SIOCSIFBRDADDR:
3604         case SIOCGIFNETMASK:
3605         case SIOCSIFNETMASK:
3606         case SIOCGIFDSTADDR:
3607         case SIOCSIFDSTADDR:
3608         case SIOCSIFFLAGS:
3609                 return inet_dgram_ops.ioctl(sock, cmd, arg);
3610 #endif
3611
3612         default:
3613                 return -ENOIOCTLCMD;
3614         }
3615         return 0;
3616 }
3617
3618 static unsigned int packet_poll(struct file *file, struct socket *sock,
3619                                 poll_table *wait)
3620 {
3621         struct sock *sk = sock->sk;
3622         struct packet_sock *po = pkt_sk(sk);
3623         unsigned int mask = datagram_poll(file, sock, wait);
3624
3625         spin_lock_bh(&sk->sk_receive_queue.lock);
3626         if (po->rx_ring.pg_vec) {
3627                 if (!packet_previous_rx_frame(po, &po->rx_ring,
3628                         TP_STATUS_KERNEL))
3629                         mask |= POLLIN | POLLRDNORM;
3630         }
3631         spin_unlock_bh(&sk->sk_receive_queue.lock);
3632         spin_lock_bh(&sk->sk_write_queue.lock);
3633         if (po->tx_ring.pg_vec) {
3634                 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
3635                         mask |= POLLOUT | POLLWRNORM;
3636         }
3637         spin_unlock_bh(&sk->sk_write_queue.lock);
3638         return mask;
3639 }
3640
3641
3642 /* Dirty? Well, I still did not learn better way to account
3643  * for user mmaps.
3644  */
3645
3646 static void packet_mm_open(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_inc(&pkt_sk(sk)->mapped);
3654 }
3655
3656 static void packet_mm_close(struct vm_area_struct *vma)
3657 {
3658         struct file *file = vma->vm_file;
3659         struct socket *sock = file->private_data;
3660         struct sock *sk = sock->sk;
3661
3662         if (sk)
3663                 atomic_dec(&pkt_sk(sk)->mapped);
3664 }
3665
3666 static const struct vm_operations_struct packet_mmap_ops = {
3667         .open   =       packet_mm_open,
3668         .close  =       packet_mm_close,
3669 };
3670
3671 static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
3672                         unsigned int len)
3673 {
3674         int i;
3675
3676         for (i = 0; i < len; i++) {
3677                 if (likely(pg_vec[i].buffer)) {
3678                         if (is_vmalloc_addr(pg_vec[i].buffer))
3679                                 vfree(pg_vec[i].buffer);
3680                         else
3681                                 free_pages((unsigned long)pg_vec[i].buffer,
3682                                            order);
3683                         pg_vec[i].buffer = NULL;
3684                 }
3685         }
3686         kfree(pg_vec);
3687 }
3688
3689 static char *alloc_one_pg_vec_page(unsigned long order)
3690 {
3691         char *buffer;
3692         gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
3693                           __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
3694
3695         buffer = (char *) __get_free_pages(gfp_flags, order);
3696         if (buffer)
3697                 return buffer;
3698
3699         /* __get_free_pages failed, fall back to vmalloc */
3700         buffer = vzalloc((1 << order) * PAGE_SIZE);
3701         if (buffer)
3702                 return buffer;
3703
3704         /* vmalloc failed, lets dig into swap here */
3705         gfp_flags &= ~__GFP_NORETRY;
3706         buffer = (char *) __get_free_pages(gfp_flags, order);
3707         if (buffer)
3708                 return buffer;
3709
3710         /* complete and utter failure */
3711         return NULL;
3712 }
3713
3714 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
3715 {
3716         unsigned int block_nr = req->tp_block_nr;
3717         struct pgv *pg_vec;
3718         int i;
3719
3720         pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
3721         if (unlikely(!pg_vec))
3722                 goto out;
3723
3724         for (i = 0; i < block_nr; i++) {
3725                 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
3726                 if (unlikely(!pg_vec[i].buffer))
3727                         goto out_free_pgvec;
3728         }
3729
3730 out:
3731         return pg_vec;
3732
3733 out_free_pgvec:
3734         free_pg_vec(pg_vec, order, block_nr);
3735         pg_vec = NULL;
3736         goto out;
3737 }
3738
3739 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
3740                 int closing, int tx_ring)
3741 {
3742         struct pgv *pg_vec = NULL;
3743         struct packet_sock *po = pkt_sk(sk);
3744         int was_running, order = 0;
3745         struct packet_ring_buffer *rb;
3746         struct sk_buff_head *rb_queue;
3747         __be16 num;
3748         int err = -EINVAL;
3749         /* Added to avoid minimal code churn */
3750         struct tpacket_req *req = &req_u->req;
3751
3752         /* Opening a Tx-ring is NOT supported in TPACKET_V3 */
3753         if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) {
3754                 WARN(1, "Tx-ring is not supported.\n");
3755                 goto out;
3756         }
3757
3758         rb = tx_ring ? &po->tx_ring : &po->rx_ring;
3759         rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
3760
3761         err = -EBUSY;
3762         if (!closing) {
3763                 if (atomic_read(&po->mapped))
3764                         goto out;
3765                 if (packet_read_pending(rb))
3766                         goto out;
3767         }
3768
3769         if (req->tp_block_nr) {
3770                 /* Sanity tests and some calculations */
3771                 err = -EBUSY;
3772                 if (unlikely(rb->pg_vec))
3773                         goto out;
3774
3775                 switch (po->tp_version) {
3776                 case TPACKET_V1:
3777                         po->tp_hdrlen = TPACKET_HDRLEN;
3778                         break;
3779                 case TPACKET_V2:
3780                         po->tp_hdrlen = TPACKET2_HDRLEN;
3781                         break;
3782                 case TPACKET_V3:
3783                         po->tp_hdrlen = TPACKET3_HDRLEN;
3784                         break;
3785                 }
3786
3787                 err = -EINVAL;
3788                 if (unlikely((int)req->tp_block_size <= 0))
3789                         goto out;
3790                 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
3791                         goto out;
3792                 if (unlikely(req->tp_frame_size < po->tp_hdrlen +
3793                                         po->tp_reserve))
3794                         goto out;
3795                 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
3796                         goto out;
3797
3798                 rb->frames_per_block = req->tp_block_size/req->tp_frame_size;
3799                 if (unlikely(rb->frames_per_block <= 0))
3800                         goto out;
3801                 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
3802                                         req->tp_frame_nr))
3803                         goto out;
3804
3805                 err = -ENOMEM;
3806                 order = get_order(req->tp_block_size);
3807                 pg_vec = alloc_pg_vec(req, order);
3808                 if (unlikely(!pg_vec))
3809                         goto out;
3810                 switch (po->tp_version) {
3811                 case TPACKET_V3:
3812                 /* Transmit path is not supported. We checked
3813                  * it above but just being paranoid
3814                  */
3815                         if (!tx_ring)
3816                                 init_prb_bdqc(po, rb, pg_vec, req_u, tx_ring);
3817                         break;
3818                 default:
3819                         break;
3820                 }
3821         }
3822         /* Done */
3823         else {
3824                 err = -EINVAL;
3825                 if (unlikely(req->tp_frame_nr))
3826                         goto out;
3827         }
3828
3829         lock_sock(sk);
3830
3831         /* Detach socket from network */
3832         spin_lock(&po->bind_lock);
3833         was_running = po->running;
3834         num = po->num;
3835         if (was_running) {
3836                 po->num = 0;
3837                 __unregister_prot_hook(sk, false);
3838         }
3839         spin_unlock(&po->bind_lock);
3840
3841         synchronize_net();
3842
3843         err = -EBUSY;
3844         mutex_lock(&po->pg_vec_lock);
3845         if (closing || atomic_read(&po->mapped) == 0) {
3846                 err = 0;
3847                 spin_lock_bh(&rb_queue->lock);
3848                 swap(rb->pg_vec, pg_vec);
3849                 rb->frame_max = (req->tp_frame_nr - 1);
3850                 rb->head = 0;
3851                 rb->frame_size = req->tp_frame_size;
3852                 spin_unlock_bh(&rb_queue->lock);
3853
3854                 swap(rb->pg_vec_order, order);
3855                 swap(rb->pg_vec_len, req->tp_block_nr);
3856
3857                 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
3858                 po->prot_hook.func = (po->rx_ring.pg_vec) ?
3859                                                 tpacket_rcv : packet_rcv;
3860                 skb_queue_purge(rb_queue);
3861                 if (atomic_read(&po->mapped))
3862                         pr_err("packet_mmap: vma is busy: %d\n",
3863                                atomic_read(&po->mapped));
3864         }
3865         mutex_unlock(&po->pg_vec_lock);
3866
3867         spin_lock(&po->bind_lock);
3868         if (was_running) {
3869                 po->num = num;
3870                 register_prot_hook(sk);
3871         }
3872         spin_unlock(&po->bind_lock);
3873         if (closing && (po->tp_version > TPACKET_V2)) {
3874                 /* Because we don't support block-based V3 on tx-ring */
3875                 if (!tx_ring)
3876                         prb_shutdown_retire_blk_timer(po, tx_ring, rb_queue);
3877         }
3878         release_sock(sk);
3879
3880         if (pg_vec)
3881                 free_pg_vec(pg_vec, order, req->tp_block_nr);
3882 out:
3883         return err;
3884 }
3885
3886 static int packet_mmap(struct file *file, struct socket *sock,
3887                 struct vm_area_struct *vma)
3888 {
3889         struct sock *sk = sock->sk;
3890         struct packet_sock *po = pkt_sk(sk);
3891         unsigned long size, expected_size;
3892         struct packet_ring_buffer *rb;
3893         unsigned long start;
3894         int err = -EINVAL;
3895         int i;
3896
3897         if (vma->vm_pgoff)
3898                 return -EINVAL;
3899
3900         mutex_lock(&po->pg_vec_lock);
3901
3902         expected_size = 0;
3903         for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3904                 if (rb->pg_vec) {
3905                         expected_size += rb->pg_vec_len
3906                                                 * rb->pg_vec_pages
3907                                                 * PAGE_SIZE;
3908                 }
3909         }
3910
3911         if (expected_size == 0)
3912                 goto out;
3913
3914         size = vma->vm_end - vma->vm_start;
3915         if (size != expected_size)
3916                 goto out;
3917
3918         start = vma->vm_start;
3919         for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
3920                 if (rb->pg_vec == NULL)
3921                         continue;
3922
3923                 for (i = 0; i < rb->pg_vec_len; i++) {
3924                         struct page *page;
3925                         void *kaddr = rb->pg_vec[i].buffer;
3926                         int pg_num;
3927
3928                         for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
3929                                 page = pgv_to_page(kaddr);
3930                                 err = vm_insert_page(vma, start, page);
3931                                 if (unlikely(err))
3932                                         goto out;
3933                                 start += PAGE_SIZE;
3934                                 kaddr += PAGE_SIZE;
3935                         }
3936                 }
3937         }
3938
3939         atomic_inc(&po->mapped);
3940         vma->vm_ops = &packet_mmap_ops;
3941         err = 0;
3942
3943 out:
3944         mutex_unlock(&po->pg_vec_lock);
3945         return err;
3946 }
3947
3948 static const struct proto_ops packet_ops_spkt = {
3949         .family =       PF_PACKET,
3950         .owner =        THIS_MODULE,
3951         .release =      packet_release,
3952         .bind =         packet_bind_spkt,
3953         .connect =      sock_no_connect,
3954         .socketpair =   sock_no_socketpair,
3955         .accept =       sock_no_accept,
3956         .getname =      packet_getname_spkt,
3957         .poll =         datagram_poll,
3958         .ioctl =        packet_ioctl,
3959         .listen =       sock_no_listen,
3960         .shutdown =     sock_no_shutdown,
3961         .setsockopt =   sock_no_setsockopt,
3962         .getsockopt =   sock_no_getsockopt,
3963         .sendmsg =      packet_sendmsg_spkt,
3964         .recvmsg =      packet_recvmsg,
3965         .mmap =         sock_no_mmap,
3966         .sendpage =     sock_no_sendpage,
3967 };
3968
3969 static const struct proto_ops packet_ops = {
3970         .family =       PF_PACKET,
3971         .owner =        THIS_MODULE,
3972         .release =      packet_release,
3973         .bind =         packet_bind,
3974         .connect =      sock_no_connect,
3975         .socketpair =   sock_no_socketpair,
3976         .accept =       sock_no_accept,
3977         .getname =      packet_getname,
3978         .poll =         packet_poll,
3979         .ioctl =        packet_ioctl,
3980         .listen =       sock_no_listen,
3981         .shutdown =     sock_no_shutdown,
3982         .setsockopt =   packet_setsockopt,
3983         .getsockopt =   packet_getsockopt,
3984         .sendmsg =      packet_sendmsg,
3985         .recvmsg =      packet_recvmsg,
3986         .mmap =         packet_mmap,
3987         .sendpage =     sock_no_sendpage,
3988 };
3989
3990 static const struct net_proto_family packet_family_ops = {
3991         .family =       PF_PACKET,
3992         .create =       packet_create,
3993         .owner  =       THIS_MODULE,
3994 };
3995
3996 static struct notifier_block packet_netdev_notifier = {
3997         .notifier_call =        packet_notifier,
3998 };
3999
4000 #ifdef CONFIG_PROC_FS
4001
4002 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
4003         __acquires(RCU)
4004 {
4005         struct net *net = seq_file_net(seq);
4006
4007         rcu_read_lock();
4008         return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
4009 }
4010
4011 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4012 {
4013         struct net *net = seq_file_net(seq);
4014         return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
4015 }
4016
4017 static void packet_seq_stop(struct seq_file *seq, void *v)
4018         __releases(RCU)
4019 {
4020         rcu_read_unlock();
4021 }
4022
4023 static int packet_seq_show(struct seq_file *seq, void *v)
4024 {
4025         if (v == SEQ_START_TOKEN)
4026                 seq_puts(seq, "sk       RefCnt Type Proto  Iface R Rmem   User   Inode\n");
4027         else {
4028                 struct sock *s = sk_entry(v);
4029                 const struct packet_sock *po = pkt_sk(s);
4030
4031                 seq_printf(seq,
4032                            "%pK %-6d %-4d %04x   %-5d %1d %-6u %-6u %-6lu\n",
4033                            s,
4034                            atomic_read(&s->sk_refcnt),
4035                            s->sk_type,
4036                            ntohs(po->num),
4037                            po->ifindex,
4038                            po->running,
4039                            atomic_read(&s->sk_rmem_alloc),
4040                            from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)),
4041                            sock_i_ino(s));
4042         }
4043
4044         return 0;
4045 }
4046
4047 static const struct seq_operations packet_seq_ops = {
4048         .start  = packet_seq_start,
4049         .next   = packet_seq_next,
4050         .stop   = packet_seq_stop,
4051         .show   = packet_seq_show,
4052 };
4053
4054 static int packet_seq_open(struct inode *inode, struct file *file)
4055 {
4056         return seq_open_net(inode, file, &packet_seq_ops,
4057                             sizeof(struct seq_net_private));
4058 }
4059
4060 static const struct file_operations packet_seq_fops = {
4061         .owner          = THIS_MODULE,
4062         .open           = packet_seq_open,
4063         .read           = seq_read,
4064         .llseek         = seq_lseek,
4065         .release        = seq_release_net,
4066 };
4067
4068 #endif
4069
4070 static int __net_init packet_net_init(struct net *net)
4071 {
4072         mutex_init(&net->packet.sklist_lock);
4073         INIT_HLIST_HEAD(&net->packet.sklist);
4074
4075         if (!proc_create("packet", 0, net->proc_net, &packet_seq_fops))
4076                 return -ENOMEM;
4077
4078         return 0;
4079 }
4080
4081 static void __net_exit packet_net_exit(struct net *net)
4082 {
4083         remove_proc_entry("packet", net->proc_net);
4084 }
4085
4086 static struct pernet_operations packet_net_ops = {
4087         .init = packet_net_init,
4088         .exit = packet_net_exit,
4089 };
4090
4091
4092 static void __exit packet_exit(void)
4093 {
4094         unregister_netdevice_notifier(&packet_netdev_notifier);
4095         unregister_pernet_subsys(&packet_net_ops);
4096         sock_unregister(PF_PACKET);
4097         proto_unregister(&packet_proto);
4098 }
4099
4100 static int __init packet_init(void)
4101 {
4102         int rc = proto_register(&packet_proto, 0);
4103
4104         if (rc != 0)
4105                 goto out;
4106
4107         sock_register(&packet_family_ops);
4108         register_pernet_subsys(&packet_net_ops);
4109         register_netdevice_notifier(&packet_netdev_notifier);
4110 out:
4111         return rc;
4112 }
4113
4114 module_init(packet_init);
4115 module_exit(packet_exit);
4116 MODULE_LICENSE("GPL");
4117 MODULE_ALIAS_NETPROTO(PF_PACKET);