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 (flags & SOF_TIMESTAMPING_RAW_HARDWARE) && 446 ktime_to_timespec_cond(shhwtstamps->hwtstamp, ts)) 447 return TP_STATUS_TS_RAW_HARDWARE; 448 449 if (ktime_to_timespec_cond(skb->tstamp, ts)) 450 return TP_STATUS_TS_SOFTWARE; 451 452 return 0; 453 } 454 455 static __u32 __packet_set_timestamp(struct packet_sock *po, void *frame, 456 struct sk_buff *skb) 457 { 458 union tpacket_uhdr h; 459 struct timespec ts; 460 __u32 ts_status; 461 462 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp))) 463 return 0; 464 465 h.raw = frame; 466 switch (po->tp_version) { 467 case TPACKET_V1: 468 h.h1->tp_sec = ts.tv_sec; 469 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC; 470 break; 471 case TPACKET_V2: 472 h.h2->tp_sec = ts.tv_sec; 473 h.h2->tp_nsec = ts.tv_nsec; 474 break; 475 case TPACKET_V3: 476 default: 477 WARN(1, "TPACKET version not supported.\n"); 478 BUG(); 479 } 480 481 /* one flush is safe, as both fields always lie on the same cacheline */ 482 flush_dcache_page(pgv_to_page(&h.h1->tp_sec)); 483 smp_wmb(); 484 485 return ts_status; 486 } 487 488 static void *packet_lookup_frame(struct packet_sock *po, 489 struct packet_ring_buffer *rb, 490 unsigned int position, 491 int status) 492 { 493 unsigned int pg_vec_pos, frame_offset; 494 union tpacket_uhdr h; 495 496 pg_vec_pos = position / rb->frames_per_block; 497 frame_offset = position % rb->frames_per_block; 498 499 h.raw = rb->pg_vec[pg_vec_pos].buffer + 500 (frame_offset * rb->frame_size); 501 502 if (status != __packet_get_status(po, h.raw)) 503 return NULL; 504 505 return h.raw; 506 } 507 508 static void *packet_current_frame(struct packet_sock *po, 509 struct packet_ring_buffer *rb, 510 int status) 511 { 512 return packet_lookup_frame(po, rb, rb->head, status); 513 } 514 515 static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc) 516 { 517 del_timer_sync(&pkc->retire_blk_timer); 518 } 519 520 static void prb_shutdown_retire_blk_timer(struct packet_sock *po, 521 int tx_ring, 522 struct sk_buff_head *rb_queue) 523 { 524 struct tpacket_kbdq_core *pkc; 525 526 pkc = tx_ring ? GET_PBDQC_FROM_RB(&po->tx_ring) : 527 GET_PBDQC_FROM_RB(&po->rx_ring); 528 529 spin_lock_bh(&rb_queue->lock); 530 pkc->delete_blk_timer = 1; 531 spin_unlock_bh(&rb_queue->lock); 532 533 prb_del_retire_blk_timer(pkc); 534 } 535 536 static void prb_init_blk_timer(struct packet_sock *po, 537 struct tpacket_kbdq_core *pkc, 538 void (*func) (unsigned long)) 539 { 540 init_timer(&pkc->retire_blk_timer); 541 pkc->retire_blk_timer.data = (long)po; 542 pkc->retire_blk_timer.function = func; 543 pkc->retire_blk_timer.expires = jiffies; 544 } 545 546 static void prb_setup_retire_blk_timer(struct packet_sock *po, int tx_ring) 547 { 548 struct tpacket_kbdq_core *pkc; 549 550 if (tx_ring) 551 BUG(); 552 553 pkc = tx_ring ? GET_PBDQC_FROM_RB(&po->tx_ring) : 554 GET_PBDQC_FROM_RB(&po->rx_ring); 555 prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired); 556 } 557 558 static int prb_calc_retire_blk_tmo(struct packet_sock *po, 559 int blk_size_in_bytes) 560 { 561 struct net_device *dev; 562 unsigned int mbits = 0, msec = 0, div = 0, tmo = 0; 563 struct ethtool_cmd ecmd; 564 int err; 565 u32 speed; 566 567 rtnl_lock(); 568 dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex); 569 if (unlikely(!dev)) { 570 rtnl_unlock(); 571 return DEFAULT_PRB_RETIRE_TOV; 572 } 573 err = __ethtool_get_settings(dev, &ecmd); 574 speed = ethtool_cmd_speed(&ecmd); 575 rtnl_unlock(); 576 if (!err) { 577 /* 578 * If the link speed is so slow you don't really 579 * need to worry about perf anyways 580 */ 581 if (speed < SPEED_1000 || speed == SPEED_UNKNOWN) { 582 return DEFAULT_PRB_RETIRE_TOV; 583 } else { 584 msec = 1; 585 div = speed / 1000; 586 } 587 } 588 589 mbits = (blk_size_in_bytes * 8) / (1024 * 1024); 590 591 if (div) 592 mbits /= div; 593 594 tmo = mbits * msec; 595 596 if (div) 597 return tmo+1; 598 return tmo; 599 } 600 601 static void prb_init_ft_ops(struct tpacket_kbdq_core *p1, 602 union tpacket_req_u *req_u) 603 { 604 p1->feature_req_word = req_u->req3.tp_feature_req_word; 605 } 606 607 static void init_prb_bdqc(struct packet_sock *po, 608 struct packet_ring_buffer *rb, 609 struct pgv *pg_vec, 610 union tpacket_req_u *req_u, int tx_ring) 611 { 612 struct tpacket_kbdq_core *p1 = GET_PBDQC_FROM_RB(rb); 613 struct tpacket_block_desc *pbd; 614 615 memset(p1, 0x0, sizeof(*p1)); 616 617 p1->knxt_seq_num = 1; 618 p1->pkbdq = pg_vec; 619 pbd = (struct tpacket_block_desc *)pg_vec[0].buffer; 620 p1->pkblk_start = pg_vec[0].buffer; 621 p1->kblk_size = req_u->req3.tp_block_size; 622 p1->knum_blocks = req_u->req3.tp_block_nr; 623 p1->hdrlen = po->tp_hdrlen; 624 p1->version = po->tp_version; 625 p1->last_kactive_blk_num = 0; 626 po->stats.stats3.tp_freeze_q_cnt = 0; 627 if (req_u->req3.tp_retire_blk_tov) 628 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov; 629 else 630 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po, 631 req_u->req3.tp_block_size); 632 p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov); 633 p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv; 634 635 p1->max_frame_len = p1->kblk_size - BLK_PLUS_PRIV(p1->blk_sizeof_priv); 636 prb_init_ft_ops(p1, req_u); 637 prb_setup_retire_blk_timer(po, tx_ring); 638 prb_open_block(p1, pbd); 639 } 640 641 /* Do NOT update the last_blk_num first. 642 * Assumes sk_buff_head lock is held. 643 */ 644 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc) 645 { 646 mod_timer(&pkc->retire_blk_timer, 647 jiffies + pkc->tov_in_jiffies); 648 pkc->last_kactive_blk_num = pkc->kactive_blk_num; 649 } 650 651 /* 652 * Timer logic: 653 * 1) We refresh the timer only when we open a block. 654 * By doing this we don't waste cycles refreshing the timer 655 * on packet-by-packet basis. 656 * 657 * With a 1MB block-size, on a 1Gbps line, it will take 658 * i) ~8 ms to fill a block + ii) memcpy etc. 659 * In this cut we are not accounting for the memcpy time. 660 * 661 * So, if the user sets the 'tmo' to 10ms then the timer 662 * will never fire while the block is still getting filled 663 * (which is what we want). However, the user could choose 664 * to close a block early and that's fine. 665 * 666 * But when the timer does fire, we check whether or not to refresh it. 667 * Since the tmo granularity is in msecs, it is not too expensive 668 * to refresh the timer, lets say every '8' msecs. 669 * Either the user can set the 'tmo' or we can derive it based on 670 * a) line-speed and b) block-size. 671 * prb_calc_retire_blk_tmo() calculates the tmo. 672 * 673 */ 674 static void prb_retire_rx_blk_timer_expired(unsigned long data) 675 { 676 struct packet_sock *po = (struct packet_sock *)data; 677 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(&po->rx_ring); 678 unsigned int frozen; 679 struct tpacket_block_desc *pbd; 680 681 spin_lock(&po->sk.sk_receive_queue.lock); 682 683 frozen = prb_queue_frozen(pkc); 684 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc); 685 686 if (unlikely(pkc->delete_blk_timer)) 687 goto out; 688 689 /* We only need to plug the race when the block is partially filled. 690 * tpacket_rcv: 691 * lock(); increment BLOCK_NUM_PKTS; unlock() 692 * copy_bits() is in progress ... 693 * timer fires on other cpu: 694 * we can't retire the current block because copy_bits 695 * is in progress. 696 * 697 */ 698 if (BLOCK_NUM_PKTS(pbd)) { 699 while (atomic_read(&pkc->blk_fill_in_prog)) { 700 /* Waiting for skb_copy_bits to finish... */ 701 cpu_relax(); 702 } 703 } 704 705 if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) { 706 if (!frozen) { 707 prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO); 708 if (!prb_dispatch_next_block(pkc, po)) 709 goto refresh_timer; 710 else 711 goto out; 712 } else { 713 /* Case 1. Queue was frozen because user-space was 714 * lagging behind. 715 */ 716 if (prb_curr_blk_in_use(pkc, pbd)) { 717 /* 718 * Ok, user-space is still behind. 719 * So just refresh the timer. 720 */ 721 goto refresh_timer; 722 } else { 723 /* Case 2. queue was frozen,user-space caught up, 724 * now the link went idle && the timer fired. 725 * We don't have a block to close.So we open this 726 * block and restart the timer. 727 * opening a block thaws the queue,restarts timer 728 * Thawing/timer-refresh is a side effect. 729 */ 730 prb_open_block(pkc, pbd); 731 goto out; 732 } 733 } 734 } 735 736 refresh_timer: 737 _prb_refresh_rx_retire_blk_timer(pkc); 738 739 out: 740 spin_unlock(&po->sk.sk_receive_queue.lock); 741 } 742 743 static void prb_flush_block(struct tpacket_kbdq_core *pkc1, 744 struct tpacket_block_desc *pbd1, __u32 status) 745 { 746 /* Flush everything minus the block header */ 747 748 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1 749 u8 *start, *end; 750 751 start = (u8 *)pbd1; 752 753 /* Skip the block header(we know header WILL fit in 4K) */ 754 start += PAGE_SIZE; 755 756 end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end); 757 for (; start < end; start += PAGE_SIZE) 758 flush_dcache_page(pgv_to_page(start)); 759 760 smp_wmb(); 761 #endif 762 763 /* Now update the block status. */ 764 765 BLOCK_STATUS(pbd1) = status; 766 767 /* Flush the block header */ 768 769 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1 770 start = (u8 *)pbd1; 771 flush_dcache_page(pgv_to_page(start)); 772 773 smp_wmb(); 774 #endif 775 } 776 777 /* 778 * Side effect: 779 * 780 * 1) flush the block 781 * 2) Increment active_blk_num 782 * 783 * Note:We DONT refresh the timer on purpose. 784 * Because almost always the next block will be opened. 785 */ 786 static void prb_close_block(struct tpacket_kbdq_core *pkc1, 787 struct tpacket_block_desc *pbd1, 788 struct packet_sock *po, unsigned int stat) 789 { 790 __u32 status = TP_STATUS_USER | stat; 791 792 struct tpacket3_hdr *last_pkt; 793 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1; 794 795 if (po->stats.stats3.tp_drops) 796 status |= TP_STATUS_LOSING; 797 798 last_pkt = (struct tpacket3_hdr *)pkc1->prev; 799 last_pkt->tp_next_offset = 0; 800 801 /* Get the ts of the last pkt */ 802 if (BLOCK_NUM_PKTS(pbd1)) { 803 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec; 804 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec; 805 } else { 806 /* Ok, we tmo'd - so get the current time */ 807 struct timespec ts; 808 getnstimeofday(&ts); 809 h1->ts_last_pkt.ts_sec = ts.tv_sec; 810 h1->ts_last_pkt.ts_nsec = ts.tv_nsec; 811 } 812 813 smp_wmb(); 814 815 /* Flush the block */ 816 prb_flush_block(pkc1, pbd1, status); 817 818 pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1); 819 } 820 821 static void prb_thaw_queue(struct tpacket_kbdq_core *pkc) 822 { 823 pkc->reset_pending_on_curr_blk = 0; 824 } 825 826 /* 827 * Side effect of opening a block: 828 * 829 * 1) prb_queue is thawed. 830 * 2) retire_blk_timer is refreshed. 831 * 832 */ 833 static void prb_open_block(struct tpacket_kbdq_core *pkc1, 834 struct tpacket_block_desc *pbd1) 835 { 836 struct timespec ts; 837 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1; 838 839 smp_rmb(); 840 841 /* We could have just memset this but we will lose the 842 * flexibility of making the priv area sticky 843 */ 844 845 BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++; 846 BLOCK_NUM_PKTS(pbd1) = 0; 847 BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv); 848 849 getnstimeofday(&ts); 850 851 h1->ts_first_pkt.ts_sec = ts.tv_sec; 852 h1->ts_first_pkt.ts_nsec = ts.tv_nsec; 853 854 pkc1->pkblk_start = (char *)pbd1; 855 pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv); 856 857 BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv); 858 BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN; 859 860 pbd1->version = pkc1->version; 861 pkc1->prev = pkc1->nxt_offset; 862 pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size; 863 864 prb_thaw_queue(pkc1); 865 _prb_refresh_rx_retire_blk_timer(pkc1); 866 867 smp_wmb(); 868 } 869 870 /* 871 * Queue freeze logic: 872 * 1) Assume tp_block_nr = 8 blocks. 873 * 2) At time 't0', user opens Rx ring. 874 * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7 875 * 4) user-space is either sleeping or processing block '0'. 876 * 5) tpacket_rcv is currently filling block '7', since there is no space left, 877 * it will close block-7,loop around and try to fill block '0'. 878 * call-flow: 879 * __packet_lookup_frame_in_block 880 * prb_retire_current_block() 881 * prb_dispatch_next_block() 882 * |->(BLOCK_STATUS == USER) evaluates to true 883 * 5.1) Since block-0 is currently in-use, we just freeze the queue. 884 * 6) Now there are two cases: 885 * 6.1) Link goes idle right after the queue is frozen. 886 * But remember, the last open_block() refreshed the timer. 887 * When this timer expires,it will refresh itself so that we can 888 * re-open block-0 in near future. 889 * 6.2) Link is busy and keeps on receiving packets. This is a simple 890 * case and __packet_lookup_frame_in_block will check if block-0 891 * is free and can now be re-used. 892 */ 893 static void prb_freeze_queue(struct tpacket_kbdq_core *pkc, 894 struct packet_sock *po) 895 { 896 pkc->reset_pending_on_curr_blk = 1; 897 po->stats.stats3.tp_freeze_q_cnt++; 898 } 899 900 #define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT)) 901 902 /* 903 * If the next block is free then we will dispatch it 904 * and return a good offset. 905 * Else, we will freeze the queue. 906 * So, caller must check the return value. 907 */ 908 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc, 909 struct packet_sock *po) 910 { 911 struct tpacket_block_desc *pbd; 912 913 smp_rmb(); 914 915 /* 1. Get current block num */ 916 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc); 917 918 /* 2. If this block is currently in_use then freeze the queue */ 919 if (TP_STATUS_USER & BLOCK_STATUS(pbd)) { 920 prb_freeze_queue(pkc, po); 921 return NULL; 922 } 923 924 /* 925 * 3. 926 * open this block and return the offset where the first packet 927 * needs to get stored. 928 */ 929 prb_open_block(pkc, pbd); 930 return (void *)pkc->nxt_offset; 931 } 932 933 static void prb_retire_current_block(struct tpacket_kbdq_core *pkc, 934 struct packet_sock *po, unsigned int status) 935 { 936 struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc); 937 938 /* retire/close the current block */ 939 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) { 940 /* 941 * Plug the case where copy_bits() is in progress on 942 * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't 943 * have space to copy the pkt in the current block and 944 * called prb_retire_current_block() 945 * 946 * We don't need to worry about the TMO case because 947 * the timer-handler already handled this case. 948 */ 949 if (!(status & TP_STATUS_BLK_TMO)) { 950 while (atomic_read(&pkc->blk_fill_in_prog)) { 951 /* Waiting for skb_copy_bits to finish... */ 952 cpu_relax(); 953 } 954 } 955 prb_close_block(pkc, pbd, po, status); 956 return; 957 } 958 } 959 960 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc, 961 struct tpacket_block_desc *pbd) 962 { 963 return TP_STATUS_USER & BLOCK_STATUS(pbd); 964 } 965 966 static int prb_queue_frozen(struct tpacket_kbdq_core *pkc) 967 { 968 return pkc->reset_pending_on_curr_blk; 969 } 970 971 static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb) 972 { 973 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb); 974 atomic_dec(&pkc->blk_fill_in_prog); 975 } 976 977 static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc, 978 struct tpacket3_hdr *ppd) 979 { 980 ppd->hv1.tp_rxhash = skb_get_hash(pkc->skb); 981 } 982 983 static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc, 984 struct tpacket3_hdr *ppd) 985 { 986 ppd->hv1.tp_rxhash = 0; 987 } 988 989 static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc, 990 struct tpacket3_hdr *ppd) 991 { 992 if (vlan_tx_tag_present(pkc->skb)) { 993 ppd->hv1.tp_vlan_tci = vlan_tx_tag_get(pkc->skb); 994 ppd->hv1.tp_vlan_tpid = ntohs(pkc->skb->vlan_proto); 995 ppd->tp_status = TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID; 996 } else { 997 ppd->hv1.tp_vlan_tci = 0; 998 ppd->hv1.tp_vlan_tpid = 0; 999 ppd->tp_status = TP_STATUS_AVAILABLE; 1000 } 1001 } 1002 1003 static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc, 1004 struct tpacket3_hdr *ppd) 1005 { 1006 ppd->hv1.tp_padding = 0; 1007 prb_fill_vlan_info(pkc, ppd); 1008 1009 if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH) 1010 prb_fill_rxhash(pkc, ppd); 1011 else 1012 prb_clear_rxhash(pkc, ppd); 1013 } 1014 1015 static void prb_fill_curr_block(char *curr, 1016 struct tpacket_kbdq_core *pkc, 1017 struct tpacket_block_desc *pbd, 1018 unsigned int len) 1019 { 1020 struct tpacket3_hdr *ppd; 1021 1022 ppd = (struct tpacket3_hdr *)curr; 1023 ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len); 1024 pkc->prev = curr; 1025 pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len); 1026 BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len); 1027 BLOCK_NUM_PKTS(pbd) += 1; 1028 atomic_inc(&pkc->blk_fill_in_prog); 1029 prb_run_all_ft_ops(pkc, ppd); 1030 } 1031 1032 /* Assumes caller has the sk->rx_queue.lock */ 1033 static void *__packet_lookup_frame_in_block(struct packet_sock *po, 1034 struct sk_buff *skb, 1035 int status, 1036 unsigned int len 1037 ) 1038 { 1039 struct tpacket_kbdq_core *pkc; 1040 struct tpacket_block_desc *pbd; 1041 char *curr, *end; 1042 1043 pkc = GET_PBDQC_FROM_RB(&po->rx_ring); 1044 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc); 1045 1046 /* Queue is frozen when user space is lagging behind */ 1047 if (prb_queue_frozen(pkc)) { 1048 /* 1049 * Check if that last block which caused the queue to freeze, 1050 * is still in_use by user-space. 1051 */ 1052 if (prb_curr_blk_in_use(pkc, pbd)) { 1053 /* Can't record this packet */ 1054 return NULL; 1055 } else { 1056 /* 1057 * Ok, the block was released by user-space. 1058 * Now let's open that block. 1059 * opening a block also thaws the queue. 1060 * Thawing is a side effect. 1061 */ 1062 prb_open_block(pkc, pbd); 1063 } 1064 } 1065 1066 smp_mb(); 1067 curr = pkc->nxt_offset; 1068 pkc->skb = skb; 1069 end = (char *)pbd + pkc->kblk_size; 1070 1071 /* first try the current block */ 1072 if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) { 1073 prb_fill_curr_block(curr, pkc, pbd, len); 1074 return (void *)curr; 1075 } 1076 1077 /* Ok, close the current block */ 1078 prb_retire_current_block(pkc, po, 0); 1079 1080 /* Now, try to dispatch the next block */ 1081 curr = (char *)prb_dispatch_next_block(pkc, po); 1082 if (curr) { 1083 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc); 1084 prb_fill_curr_block(curr, pkc, pbd, len); 1085 return (void *)curr; 1086 } 1087 1088 /* 1089 * No free blocks are available.user_space hasn't caught up yet. 1090 * Queue was just frozen and now this packet will get dropped. 1091 */ 1092 return NULL; 1093 } 1094 1095 static void *packet_current_rx_frame(struct packet_sock *po, 1096 struct sk_buff *skb, 1097 int status, unsigned int len) 1098 { 1099 char *curr = NULL; 1100 switch (po->tp_version) { 1101 case TPACKET_V1: 1102 case TPACKET_V2: 1103 curr = packet_lookup_frame(po, &po->rx_ring, 1104 po->rx_ring.head, status); 1105 return curr; 1106 case TPACKET_V3: 1107 return __packet_lookup_frame_in_block(po, skb, status, len); 1108 default: 1109 WARN(1, "TPACKET version not supported\n"); 1110 BUG(); 1111 return NULL; 1112 } 1113 } 1114 1115 static void *prb_lookup_block(struct packet_sock *po, 1116 struct packet_ring_buffer *rb, 1117 unsigned int idx, 1118 int status) 1119 { 1120 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb); 1121 struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, idx); 1122 1123 if (status != BLOCK_STATUS(pbd)) 1124 return NULL; 1125 return pbd; 1126 } 1127 1128 static int prb_previous_blk_num(struct packet_ring_buffer *rb) 1129 { 1130 unsigned int prev; 1131 if (rb->prb_bdqc.kactive_blk_num) 1132 prev = rb->prb_bdqc.kactive_blk_num-1; 1133 else 1134 prev = rb->prb_bdqc.knum_blocks-1; 1135 return prev; 1136 } 1137 1138 /* Assumes caller has held the rx_queue.lock */ 1139 static void *__prb_previous_block(struct packet_sock *po, 1140 struct packet_ring_buffer *rb, 1141 int status) 1142 { 1143 unsigned int previous = prb_previous_blk_num(rb); 1144 return prb_lookup_block(po, rb, previous, status); 1145 } 1146 1147 static void *packet_previous_rx_frame(struct packet_sock *po, 1148 struct packet_ring_buffer *rb, 1149 int status) 1150 { 1151 if (po->tp_version <= TPACKET_V2) 1152 return packet_previous_frame(po, rb, status); 1153 1154 return __prb_previous_block(po, rb, status); 1155 } 1156 1157 static void packet_increment_rx_head(struct packet_sock *po, 1158 struct packet_ring_buffer *rb) 1159 { 1160 switch (po->tp_version) { 1161 case TPACKET_V1: 1162 case TPACKET_V2: 1163 return packet_increment_head(rb); 1164 case TPACKET_V3: 1165 default: 1166 WARN(1, "TPACKET version not supported.\n"); 1167 BUG(); 1168 return; 1169 } 1170 } 1171 1172 static void *packet_previous_frame(struct packet_sock *po, 1173 struct packet_ring_buffer *rb, 1174 int status) 1175 { 1176 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max; 1177 return packet_lookup_frame(po, rb, previous, status); 1178 } 1179 1180 static void packet_increment_head(struct packet_ring_buffer *buff) 1181 { 1182 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0; 1183 } 1184 1185 static void packet_inc_pending(struct packet_ring_buffer *rb) 1186 { 1187 this_cpu_inc(*rb->pending_refcnt); 1188 } 1189 1190 static void packet_dec_pending(struct packet_ring_buffer *rb) 1191 { 1192 this_cpu_dec(*rb->pending_refcnt); 1193 } 1194 1195 static unsigned int packet_read_pending(const struct packet_ring_buffer *rb) 1196 { 1197 unsigned int refcnt = 0; 1198 int cpu; 1199 1200 /* We don't use pending refcount in rx_ring. */ 1201 if (rb->pending_refcnt == NULL) 1202 return 0; 1203 1204 for_each_possible_cpu(cpu) 1205 refcnt += *per_cpu_ptr(rb->pending_refcnt, cpu); 1206 1207 return refcnt; 1208 } 1209 1210 static int packet_alloc_pending(struct packet_sock *po) 1211 { 1212 po->rx_ring.pending_refcnt = NULL; 1213 1214 po->tx_ring.pending_refcnt = alloc_percpu(unsigned int); 1215 if (unlikely(po->tx_ring.pending_refcnt == NULL)) 1216 return -ENOBUFS; 1217 1218 return 0; 1219 } 1220 1221 static void packet_free_pending(struct packet_sock *po) 1222 { 1223 free_percpu(po->tx_ring.pending_refcnt); 1224 } 1225 1226 static bool packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb) 1227 { 1228 struct sock *sk = &po->sk; 1229 bool has_room; 1230 1231 if (po->prot_hook.func != tpacket_rcv) 1232 return (atomic_read(&sk->sk_rmem_alloc) + skb->truesize) 1233 <= sk->sk_rcvbuf; 1234 1235 spin_lock(&sk->sk_receive_queue.lock); 1236 if (po->tp_version == TPACKET_V3) 1237 has_room = prb_lookup_block(po, &po->rx_ring, 1238 po->rx_ring.prb_bdqc.kactive_blk_num, 1239 TP_STATUS_KERNEL); 1240 else 1241 has_room = packet_lookup_frame(po, &po->rx_ring, 1242 po->rx_ring.head, 1243 TP_STATUS_KERNEL); 1244 spin_unlock(&sk->sk_receive_queue.lock); 1245 1246 return has_room; 1247 } 1248 1249 static void packet_sock_destruct(struct sock *sk) 1250 { 1251 skb_queue_purge(&sk->sk_error_queue); 1252 1253 WARN_ON(atomic_read(&sk->sk_rmem_alloc)); 1254 WARN_ON(atomic_read(&sk->sk_wmem_alloc)); 1255 1256 if (!sock_flag(sk, SOCK_DEAD)) { 1257 pr_err("Attempt to release alive packet socket: %p\n", sk); 1258 return; 1259 } 1260 1261 sk_refcnt_debug_dec(sk); 1262 } 1263 1264 static int fanout_rr_next(struct packet_fanout *f, unsigned int num) 1265 { 1266 int x = atomic_read(&f->rr_cur) + 1; 1267 1268 if (x >= num) 1269 x = 0; 1270 1271 return x; 1272 } 1273 1274 static unsigned int fanout_demux_hash(struct packet_fanout *f, 1275 struct sk_buff *skb, 1276 unsigned int num) 1277 { 1278 return reciprocal_scale(skb_get_hash(skb), num); 1279 } 1280 1281 static unsigned int fanout_demux_lb(struct packet_fanout *f, 1282 struct sk_buff *skb, 1283 unsigned int num) 1284 { 1285 int cur, old; 1286 1287 cur = atomic_read(&f->rr_cur); 1288 while ((old = atomic_cmpxchg(&f->rr_cur, cur, 1289 fanout_rr_next(f, num))) != cur) 1290 cur = old; 1291 return cur; 1292 } 1293 1294 static unsigned int fanout_demux_cpu(struct packet_fanout *f, 1295 struct sk_buff *skb, 1296 unsigned int num) 1297 { 1298 return smp_processor_id() % num; 1299 } 1300 1301 static unsigned int fanout_demux_rnd(struct packet_fanout *f, 1302 struct sk_buff *skb, 1303 unsigned int num) 1304 { 1305 return prandom_u32_max(num); 1306 } 1307 1308 static unsigned int fanout_demux_rollover(struct packet_fanout *f, 1309 struct sk_buff *skb, 1310 unsigned int idx, unsigned int skip, 1311 unsigned int num) 1312 { 1313 unsigned int i, j; 1314 1315 i = j = min_t(int, f->next[idx], num - 1); 1316 do { 1317 if (i != skip && packet_rcv_has_room(pkt_sk(f->arr[i]), skb)) { 1318 if (i != j) 1319 f->next[idx] = i; 1320 return i; 1321 } 1322 if (++i == num) 1323 i = 0; 1324 } while (i != j); 1325 1326 return idx; 1327 } 1328 1329 static unsigned int fanout_demux_qm(struct packet_fanout *f, 1330 struct sk_buff *skb, 1331 unsigned int num) 1332 { 1333 return skb_get_queue_mapping(skb) % num; 1334 } 1335 1336 static bool fanout_has_flag(struct packet_fanout *f, u16 flag) 1337 { 1338 return f->flags & (flag >> 8); 1339 } 1340 1341 static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev, 1342 struct packet_type *pt, struct net_device *orig_dev) 1343 { 1344 struct packet_fanout *f = pt->af_packet_priv; 1345 unsigned int num = f->num_members; 1346 struct packet_sock *po; 1347 unsigned int idx; 1348 1349 if (!net_eq(dev_net(dev), read_pnet(&f->net)) || 1350 !num) { 1351 kfree_skb(skb); 1352 return 0; 1353 } 1354 1355 switch (f->type) { 1356 case PACKET_FANOUT_HASH: 1357 default: 1358 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_DEFRAG)) { 1359 skb = ip_check_defrag(skb, IP_DEFRAG_AF_PACKET); 1360 if (!skb) 1361 return 0; 1362 } 1363 idx = fanout_demux_hash(f, skb, num); 1364 break; 1365 case PACKET_FANOUT_LB: 1366 idx = fanout_demux_lb(f, skb, num); 1367 break; 1368 case PACKET_FANOUT_CPU: 1369 idx = fanout_demux_cpu(f, skb, num); 1370 break; 1371 case PACKET_FANOUT_RND: 1372 idx = fanout_demux_rnd(f, skb, num); 1373 break; 1374 case PACKET_FANOUT_QM: 1375 idx = fanout_demux_qm(f, skb, num); 1376 break; 1377 case PACKET_FANOUT_ROLLOVER: 1378 idx = fanout_demux_rollover(f, skb, 0, (unsigned int) -1, num); 1379 break; 1380 } 1381 1382 po = pkt_sk(f->arr[idx]); 1383 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER) && 1384 unlikely(!packet_rcv_has_room(po, skb))) { 1385 idx = fanout_demux_rollover(f, skb, idx, idx, num); 1386 po = pkt_sk(f->arr[idx]); 1387 } 1388 1389 return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev); 1390 } 1391 1392 DEFINE_MUTEX(fanout_mutex); 1393 EXPORT_SYMBOL_GPL(fanout_mutex); 1394 static LIST_HEAD(fanout_list); 1395 1396 static void __fanout_link(struct sock *sk, struct packet_sock *po) 1397 { 1398 struct packet_fanout *f = po->fanout; 1399 1400 spin_lock(&f->lock); 1401 f->arr[f->num_members] = sk; 1402 smp_wmb(); 1403 f->num_members++; 1404 spin_unlock(&f->lock); 1405 } 1406 1407 static void __fanout_unlink(struct sock *sk, struct packet_sock *po) 1408 { 1409 struct packet_fanout *f = po->fanout; 1410 int i; 1411 1412 spin_lock(&f->lock); 1413 for (i = 0; i < f->num_members; i++) { 1414 if (f->arr[i] == sk) 1415 break; 1416 } 1417 BUG_ON(i >= f->num_members); 1418 f->arr[i] = f->arr[f->num_members - 1]; 1419 f->num_members--; 1420 spin_unlock(&f->lock); 1421 } 1422 1423 static bool match_fanout_group(struct packet_type *ptype, struct sock *sk) 1424 { 1425 if (ptype->af_packet_priv == (void *)((struct packet_sock *)sk)->fanout) 1426 return true; 1427 1428 return false; 1429 } 1430 1431 static int fanout_add(struct sock *sk, u16 id, u16 type_flags) 1432 { 1433 struct packet_sock *po = pkt_sk(sk); 1434 struct packet_fanout *f, *match; 1435 u8 type = type_flags & 0xff; 1436 u8 flags = type_flags >> 8; 1437 int err; 1438 1439 switch (type) { 1440 case PACKET_FANOUT_ROLLOVER: 1441 if (type_flags & PACKET_FANOUT_FLAG_ROLLOVER) 1442 return -EINVAL; 1443 case PACKET_FANOUT_HASH: 1444 case PACKET_FANOUT_LB: 1445 case PACKET_FANOUT_CPU: 1446 case PACKET_FANOUT_RND: 1447 case PACKET_FANOUT_QM: 1448 break; 1449 default: 1450 return -EINVAL; 1451 } 1452 1453 if (!po->running) 1454 return -EINVAL; 1455 1456 if (po->fanout) 1457 return -EALREADY; 1458 1459 mutex_lock(&fanout_mutex); 1460 match = NULL; 1461 list_for_each_entry(f, &fanout_list, list) { 1462 if (f->id == id && 1463 read_pnet(&f->net) == sock_net(sk)) { 1464 match = f; 1465 break; 1466 } 1467 } 1468 err = -EINVAL; 1469 if (match && match->flags != flags) 1470 goto out; 1471 if (!match) { 1472 err = -ENOMEM; 1473 match = kzalloc(sizeof(*match), GFP_KERNEL); 1474 if (!match) 1475 goto out; 1476 write_pnet(&match->net, sock_net(sk)); 1477 match->id = id; 1478 match->type = type; 1479 match->flags = flags; 1480 atomic_set(&match->rr_cur, 0); 1481 INIT_LIST_HEAD(&match->list); 1482 spin_lock_init(&match->lock); 1483 atomic_set(&match->sk_ref, 0); 1484 match->prot_hook.type = po->prot_hook.type; 1485 match->prot_hook.dev = po->prot_hook.dev; 1486 match->prot_hook.func = packet_rcv_fanout; 1487 match->prot_hook.af_packet_priv = match; 1488 match->prot_hook.id_match = match_fanout_group; 1489 dev_add_pack(&match->prot_hook); 1490 list_add(&match->list, &fanout_list); 1491 } 1492 err = -EINVAL; 1493 if (match->type == type && 1494 match->prot_hook.type == po->prot_hook.type && 1495 match->prot_hook.dev == po->prot_hook.dev) { 1496 err = -ENOSPC; 1497 if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) { 1498 __dev_remove_pack(&po->prot_hook); 1499 po->fanout = match; 1500 atomic_inc(&match->sk_ref); 1501 __fanout_link(sk, po); 1502 err = 0; 1503 } 1504 } 1505 out: 1506 mutex_unlock(&fanout_mutex); 1507 return err; 1508 } 1509 1510 static void fanout_release(struct sock *sk) 1511 { 1512 struct packet_sock *po = pkt_sk(sk); 1513 struct packet_fanout *f; 1514 1515 f = po->fanout; 1516 if (!f) 1517 return; 1518 1519 mutex_lock(&fanout_mutex); 1520 po->fanout = NULL; 1521 1522 if (atomic_dec_and_test(&f->sk_ref)) { 1523 list_del(&f->list); 1524 dev_remove_pack(&f->prot_hook); 1525 kfree(f); 1526 } 1527 mutex_unlock(&fanout_mutex); 1528 } 1529 1530 static const struct proto_ops packet_ops; 1531 1532 static const struct proto_ops packet_ops_spkt; 1533 1534 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev, 1535 struct packet_type *pt, struct net_device *orig_dev) 1536 { 1537 struct sock *sk; 1538 struct sockaddr_pkt *spkt; 1539 1540 /* 1541 * When we registered the protocol we saved the socket in the data 1542 * field for just this event. 1543 */ 1544 1545 sk = pt->af_packet_priv; 1546 1547 /* 1548 * Yank back the headers [hope the device set this 1549 * right or kerboom...] 1550 * 1551 * Incoming packets have ll header pulled, 1552 * push it back. 1553 * 1554 * For outgoing ones skb->data == skb_mac_header(skb) 1555 * so that this procedure is noop. 1556 */ 1557 1558 if (skb->pkt_type == PACKET_LOOPBACK) 1559 goto out; 1560 1561 if (!net_eq(dev_net(dev), sock_net(sk))) 1562 goto out; 1563 1564 skb = skb_share_check(skb, GFP_ATOMIC); 1565 if (skb == NULL) 1566 goto oom; 1567 1568 /* drop any routing info */ 1569 skb_dst_drop(skb); 1570 1571 /* drop conntrack reference */ 1572 nf_reset(skb); 1573 1574 spkt = &PACKET_SKB_CB(skb)->sa.pkt; 1575 1576 skb_push(skb, skb->data - skb_mac_header(skb)); 1577 1578 /* 1579 * The SOCK_PACKET socket receives _all_ frames. 1580 */ 1581 1582 spkt->spkt_family = dev->type; 1583 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device)); 1584 spkt->spkt_protocol = skb->protocol; 1585 1586 /* 1587 * Charge the memory to the socket. This is done specifically 1588 * to prevent sockets using all the memory up. 1589 */ 1590 1591 if (sock_queue_rcv_skb(sk, skb) == 0) 1592 return 0; 1593 1594 out: 1595 kfree_skb(skb); 1596 oom: 1597 return 0; 1598 } 1599 1600 1601 /* 1602 * Output a raw packet to a device layer. This bypasses all the other 1603 * protocol layers and you must therefore supply it with a complete frame 1604 */ 1605 1606 static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock, 1607 struct msghdr *msg, size_t len) 1608 { 1609 struct sock *sk = sock->sk; 1610 DECLARE_SOCKADDR(struct sockaddr_pkt *, saddr, msg->msg_name); 1611 struct sk_buff *skb = NULL; 1612 struct net_device *dev; 1613 __be16 proto = 0; 1614 int err; 1615 int extra_len = 0; 1616 1617 /* 1618 * Get and verify the address. 1619 */ 1620 1621 if (saddr) { 1622 if (msg->msg_namelen < sizeof(struct sockaddr)) 1623 return -EINVAL; 1624 if (msg->msg_namelen == sizeof(struct sockaddr_pkt)) 1625 proto = saddr->spkt_protocol; 1626 } else 1627 return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */ 1628 1629 /* 1630 * Find the device first to size check it 1631 */ 1632 1633 saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0; 1634 retry: 1635 rcu_read_lock(); 1636 dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device); 1637 err = -ENODEV; 1638 if (dev == NULL) 1639 goto out_unlock; 1640 1641 err = -ENETDOWN; 1642 if (!(dev->flags & IFF_UP)) 1643 goto out_unlock; 1644 1645 /* 1646 * You may not queue a frame bigger than the mtu. This is the lowest level 1647 * raw protocol and you must do your own fragmentation at this level. 1648 */ 1649 1650 if (unlikely(sock_flag(sk, SOCK_NOFCS))) { 1651 if (!netif_supports_nofcs(dev)) { 1652 err = -EPROTONOSUPPORT; 1653 goto out_unlock; 1654 } 1655 extra_len = 4; /* We're doing our own CRC */ 1656 } 1657 1658 err = -EMSGSIZE; 1659 if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len) 1660 goto out_unlock; 1661 1662 if (!skb) { 1663 size_t reserved = LL_RESERVED_SPACE(dev); 1664 int tlen = dev->needed_tailroom; 1665 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0; 1666 1667 rcu_read_unlock(); 1668 skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL); 1669 if (skb == NULL) 1670 return -ENOBUFS; 1671 /* FIXME: Save some space for broken drivers that write a hard 1672 * header at transmission time by themselves. PPP is the notable 1673 * one here. This should really be fixed at the driver level. 1674 */ 1675 skb_reserve(skb, reserved); 1676 skb_reset_network_header(skb); 1677 1678 /* Try to align data part correctly */ 1679 if (hhlen) { 1680 skb->data -= hhlen; 1681 skb->tail -= hhlen; 1682 if (len < hhlen) 1683 skb_reset_network_header(skb); 1684 } 1685 err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len); 1686 if (err) 1687 goto out_free; 1688 goto retry; 1689 } 1690 1691 if (len > (dev->mtu + dev->hard_header_len + extra_len)) { 1692 /* Earlier code assumed this would be a VLAN pkt, 1693 * double-check this now that we have the actual 1694 * packet in hand. 1695 */ 1696 struct ethhdr *ehdr; 1697 skb_reset_mac_header(skb); 1698 ehdr = eth_hdr(skb); 1699 if (ehdr->h_proto != htons(ETH_P_8021Q)) { 1700 err = -EMSGSIZE; 1701 goto out_unlock; 1702 } 1703 } 1704 1705 skb->protocol = proto; 1706 skb->dev = dev; 1707 skb->priority = sk->sk_priority; 1708 skb->mark = sk->sk_mark; 1709 1710 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags); 1711 1712 if (unlikely(extra_len == 4)) 1713 skb->no_fcs = 1; 1714 1715 skb_probe_transport_header(skb, 0); 1716 1717 dev_queue_xmit(skb); 1718 rcu_read_unlock(); 1719 return len; 1720 1721 out_unlock: 1722 rcu_read_unlock(); 1723 out_free: 1724 kfree_skb(skb); 1725 return err; 1726 } 1727 1728 static unsigned int run_filter(const struct sk_buff *skb, 1729 const struct sock *sk, 1730 unsigned int res) 1731 { 1732 struct sk_filter *filter; 1733 1734 rcu_read_lock(); 1735 filter = rcu_dereference(sk->sk_filter); 1736 if (filter != NULL) 1737 res = SK_RUN_FILTER(filter, skb); 1738 rcu_read_unlock(); 1739 1740 return res; 1741 } 1742 1743 /* 1744 * This function makes lazy skb cloning in hope that most of packets 1745 * are discarded by BPF. 1746 * 1747 * Note tricky part: we DO mangle shared skb! skb->data, skb->len 1748 * and skb->cb are mangled. It works because (and until) packets 1749 * falling here are owned by current CPU. Output packets are cloned 1750 * by dev_queue_xmit_nit(), input packets are processed by net_bh 1751 * sequencially, so that if we return skb to original state on exit, 1752 * we will not harm anyone. 1753 */ 1754 1755 static int packet_rcv(struct sk_buff *skb, struct net_device *dev, 1756 struct packet_type *pt, struct net_device *orig_dev) 1757 { 1758 struct sock *sk; 1759 struct sockaddr_ll *sll; 1760 struct packet_sock *po; 1761 u8 *skb_head = skb->data; 1762 int skb_len = skb->len; 1763 unsigned int snaplen, res; 1764 1765 if (skb->pkt_type == PACKET_LOOPBACK) 1766 goto drop; 1767 1768 sk = pt->af_packet_priv; 1769 po = pkt_sk(sk); 1770 1771 if (!net_eq(dev_net(dev), sock_net(sk))) 1772 goto drop; 1773 1774 skb->dev = dev; 1775 1776 if (dev->header_ops) { 1777 /* The device has an explicit notion of ll header, 1778 * exported to higher levels. 1779 * 1780 * Otherwise, the device hides details of its frame 1781 * structure, so that corresponding packet head is 1782 * never delivered to user. 1783 */ 1784 if (sk->sk_type != SOCK_DGRAM) 1785 skb_push(skb, skb->data - skb_mac_header(skb)); 1786 else if (skb->pkt_type == PACKET_OUTGOING) { 1787 /* Special case: outgoing packets have ll header at head */ 1788 skb_pull(skb, skb_network_offset(skb)); 1789 } 1790 } 1791 1792 snaplen = skb->len; 1793 1794 res = run_filter(skb, sk, snaplen); 1795 if (!res) 1796 goto drop_n_restore; 1797 if (snaplen > res) 1798 snaplen = res; 1799 1800 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) 1801 goto drop_n_acct; 1802 1803 if (skb_shared(skb)) { 1804 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC); 1805 if (nskb == NULL) 1806 goto drop_n_acct; 1807 1808 if (skb_head != skb->data) { 1809 skb->data = skb_head; 1810 skb->len = skb_len; 1811 } 1812 consume_skb(skb); 1813 skb = nskb; 1814 } 1815 1816 BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 > 1817 sizeof(skb->cb)); 1818 1819 sll = &PACKET_SKB_CB(skb)->sa.ll; 1820 sll->sll_family = AF_PACKET; 1821 sll->sll_hatype = dev->type; 1822 sll->sll_protocol = skb->protocol; 1823 sll->sll_pkttype = skb->pkt_type; 1824 if (unlikely(po->origdev)) 1825 sll->sll_ifindex = orig_dev->ifindex; 1826 else 1827 sll->sll_ifindex = dev->ifindex; 1828 1829 sll->sll_halen = dev_parse_header(skb, sll->sll_addr); 1830 1831 PACKET_SKB_CB(skb)->origlen = skb->len; 1832 1833 if (pskb_trim(skb, snaplen)) 1834 goto drop_n_acct; 1835 1836 skb_set_owner_r(skb, sk); 1837 skb->dev = NULL; 1838 skb_dst_drop(skb); 1839 1840 /* drop conntrack reference */ 1841 nf_reset(skb); 1842 1843 spin_lock(&sk->sk_receive_queue.lock); 1844 po->stats.stats1.tp_packets++; 1845 skb->dropcount = atomic_read(&sk->sk_drops); 1846 __skb_queue_tail(&sk->sk_receive_queue, skb); 1847 spin_unlock(&sk->sk_receive_queue.lock); 1848 sk->sk_data_ready(sk); 1849 return 0; 1850 1851 drop_n_acct: 1852 spin_lock(&sk->sk_receive_queue.lock); 1853 po->stats.stats1.tp_drops++; 1854 atomic_inc(&sk->sk_drops); 1855 spin_unlock(&sk->sk_receive_queue.lock); 1856 1857 drop_n_restore: 1858 if (skb_head != skb->data && skb_shared(skb)) { 1859 skb->data = skb_head; 1860 skb->len = skb_len; 1861 } 1862 drop: 1863 consume_skb(skb); 1864 return 0; 1865 } 1866 1867 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, 1868 struct packet_type *pt, struct net_device *orig_dev) 1869 { 1870 struct sock *sk; 1871 struct packet_sock *po; 1872 struct sockaddr_ll *sll; 1873 union tpacket_uhdr h; 1874 u8 *skb_head = skb->data; 1875 int skb_len = skb->len; 1876 unsigned int snaplen, res; 1877 unsigned long status = TP_STATUS_USER; 1878 unsigned short macoff, netoff, hdrlen; 1879 struct sk_buff *copy_skb = NULL; 1880 struct timespec ts; 1881 __u32 ts_status; 1882 1883 /* struct tpacket{2,3}_hdr is aligned to a multiple of TPACKET_ALIGNMENT. 1884 * We may add members to them until current aligned size without forcing 1885 * userspace to call getsockopt(..., PACKET_HDRLEN, ...). 1886 */ 1887 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h2)) != 32); 1888 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h3)) != 48); 1889 1890 if (skb->pkt_type == PACKET_LOOPBACK) 1891 goto drop; 1892 1893 sk = pt->af_packet_priv; 1894 po = pkt_sk(sk); 1895 1896 if (!net_eq(dev_net(dev), sock_net(sk))) 1897 goto drop; 1898 1899 if (dev->header_ops) { 1900 if (sk->sk_type != SOCK_DGRAM) 1901 skb_push(skb, skb->data - skb_mac_header(skb)); 1902 else if (skb->pkt_type == PACKET_OUTGOING) { 1903 /* Special case: outgoing packets have ll header at head */ 1904 skb_pull(skb, skb_network_offset(skb)); 1905 } 1906 } 1907 1908 if (skb->ip_summed == CHECKSUM_PARTIAL) 1909 status |= TP_STATUS_CSUMNOTREADY; 1910 1911 snaplen = skb->len; 1912 1913 res = run_filter(skb, sk, snaplen); 1914 if (!res) 1915 goto drop_n_restore; 1916 if (snaplen > res) 1917 snaplen = res; 1918 1919 if (sk->sk_type == SOCK_DGRAM) { 1920 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 + 1921 po->tp_reserve; 1922 } else { 1923 unsigned int maclen = skb_network_offset(skb); 1924 netoff = TPACKET_ALIGN(po->tp_hdrlen + 1925 (maclen < 16 ? 16 : maclen)) + 1926 po->tp_reserve; 1927 macoff = netoff - maclen; 1928 } 1929 if (po->tp_version <= TPACKET_V2) { 1930 if (macoff + snaplen > po->rx_ring.frame_size) { 1931 if (po->copy_thresh && 1932 atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) { 1933 if (skb_shared(skb)) { 1934 copy_skb = skb_clone(skb, GFP_ATOMIC); 1935 } else { 1936 copy_skb = skb_get(skb); 1937 skb_head = skb->data; 1938 } 1939 if (copy_skb) 1940 skb_set_owner_r(copy_skb, sk); 1941 } 1942 snaplen = po->rx_ring.frame_size - macoff; 1943 if ((int)snaplen < 0) 1944 snaplen = 0; 1945 } 1946 } else if (unlikely(macoff + snaplen > 1947 GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len)) { 1948 u32 nval; 1949 1950 nval = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len - macoff; 1951 pr_err_once("tpacket_rcv: packet too big, clamped from %u to %u. macoff=%u\n", 1952 snaplen, nval, macoff); 1953 snaplen = nval; 1954 if (unlikely((int)snaplen < 0)) { 1955 snaplen = 0; 1956 macoff = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len; 1957 } 1958 } 1959 spin_lock(&sk->sk_receive_queue.lock); 1960 h.raw = packet_current_rx_frame(po, skb, 1961 TP_STATUS_KERNEL, (macoff+snaplen)); 1962 if (!h.raw) 1963 goto ring_is_full; 1964 if (po->tp_version <= TPACKET_V2) { 1965 packet_increment_rx_head(po, &po->rx_ring); 1966 /* 1967 * LOSING will be reported till you read the stats, 1968 * because it's COR - Clear On Read. 1969 * Anyways, moving it for V1/V2 only as V3 doesn't need this 1970 * at packet level. 1971 */ 1972 if (po->stats.stats1.tp_drops) 1973 status |= TP_STATUS_LOSING; 1974 } 1975 po->stats.stats1.tp_packets++; 1976 if (copy_skb) { 1977 status |= TP_STATUS_COPY; 1978 __skb_queue_tail(&sk->sk_receive_queue, copy_skb); 1979 } 1980 spin_unlock(&sk->sk_receive_queue.lock); 1981 1982 skb_copy_bits(skb, 0, h.raw + macoff, snaplen); 1983 1984 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp))) 1985 getnstimeofday(&ts); 1986 1987 status |= ts_status; 1988 1989 switch (po->tp_version) { 1990 case TPACKET_V1: 1991 h.h1->tp_len = skb->len; 1992 h.h1->tp_snaplen = snaplen; 1993 h.h1->tp_mac = macoff; 1994 h.h1->tp_net = netoff; 1995 h.h1->tp_sec = ts.tv_sec; 1996 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC; 1997 hdrlen = sizeof(*h.h1); 1998 break; 1999 case TPACKET_V2: 2000 h.h2->tp_len = skb->len; 2001 h.h2->tp_snaplen = snaplen; 2002 h.h2->tp_mac = macoff; 2003 h.h2->tp_net = netoff; 2004 h.h2->tp_sec = ts.tv_sec; 2005 h.h2->tp_nsec = ts.tv_nsec; 2006 if (vlan_tx_tag_present(skb)) { 2007 h.h2->tp_vlan_tci = vlan_tx_tag_get(skb); 2008 h.h2->tp_vlan_tpid = ntohs(skb->vlan_proto); 2009 status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID; 2010 } else { 2011 h.h2->tp_vlan_tci = 0; 2012 h.h2->tp_vlan_tpid = 0; 2013 } 2014 memset(h.h2->tp_padding, 0, sizeof(h.h2->tp_padding)); 2015 hdrlen = sizeof(*h.h2); 2016 break; 2017 case TPACKET_V3: 2018 /* tp_nxt_offset,vlan are already populated above. 2019 * So DONT clear those fields here 2020 */ 2021 h.h3->tp_status |= status; 2022 h.h3->tp_len = skb->len; 2023 h.h3->tp_snaplen = snaplen; 2024 h.h3->tp_mac = macoff; 2025 h.h3->tp_net = netoff; 2026 h.h3->tp_sec = ts.tv_sec; 2027 h.h3->tp_nsec = ts.tv_nsec; 2028 memset(h.h3->tp_padding, 0, sizeof(h.h3->tp_padding)); 2029 hdrlen = sizeof(*h.h3); 2030 break; 2031 default: 2032 BUG(); 2033 } 2034 2035 sll = h.raw + TPACKET_ALIGN(hdrlen); 2036 sll->sll_halen = dev_parse_header(skb, sll->sll_addr); 2037 sll->sll_family = AF_PACKET; 2038 sll->sll_hatype = dev->type; 2039 sll->sll_protocol = skb->protocol; 2040 sll->sll_pkttype = skb->pkt_type; 2041 if (unlikely(po->origdev)) 2042 sll->sll_ifindex = orig_dev->ifindex; 2043 else 2044 sll->sll_ifindex = dev->ifindex; 2045 2046 smp_mb(); 2047 2048 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1 2049 if (po->tp_version <= TPACKET_V2) { 2050 u8 *start, *end; 2051 2052 end = (u8 *) PAGE_ALIGN((unsigned long) h.raw + 2053 macoff + snaplen); 2054 2055 for (start = h.raw; start < end; start += PAGE_SIZE) 2056 flush_dcache_page(pgv_to_page(start)); 2057 } 2058 smp_wmb(); 2059 #endif 2060 2061 if (po->tp_version <= TPACKET_V2) 2062 __packet_set_status(po, h.raw, status); 2063 else 2064 prb_clear_blk_fill_status(&po->rx_ring); 2065 2066 sk->sk_data_ready(sk); 2067 2068 drop_n_restore: 2069 if (skb_head != skb->data && skb_shared(skb)) { 2070 skb->data = skb_head; 2071 skb->len = skb_len; 2072 } 2073 drop: 2074 kfree_skb(skb); 2075 return 0; 2076 2077 ring_is_full: 2078 po->stats.stats1.tp_drops++; 2079 spin_unlock(&sk->sk_receive_queue.lock); 2080 2081 sk->sk_data_ready(sk); 2082 kfree_skb(copy_skb); 2083 goto drop_n_restore; 2084 } 2085 2086 static void tpacket_destruct_skb(struct sk_buff *skb) 2087 { 2088 struct packet_sock *po = pkt_sk(skb->sk); 2089 2090 if (likely(po->tx_ring.pg_vec)) { 2091 void *ph; 2092 __u32 ts; 2093 2094 ph = skb_shinfo(skb)->destructor_arg; 2095 packet_dec_pending(&po->tx_ring); 2096 2097 ts = __packet_set_timestamp(po, ph, skb); 2098 __packet_set_status(po, ph, TP_STATUS_AVAILABLE | ts); 2099 } 2100 2101 sock_wfree(skb); 2102 } 2103 2104 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb, 2105 void *frame, struct net_device *dev, int size_max, 2106 __be16 proto, unsigned char *addr, int hlen) 2107 { 2108 union tpacket_uhdr ph; 2109 int to_write, offset, len, tp_len, nr_frags, len_max; 2110 struct socket *sock = po->sk.sk_socket; 2111 struct page *page; 2112 void *data; 2113 int err; 2114 2115 ph.raw = frame; 2116 2117 skb->protocol = proto; 2118 skb->dev = dev; 2119 skb->priority = po->sk.sk_priority; 2120 skb->mark = po->sk.sk_mark; 2121 sock_tx_timestamp(&po->sk, &skb_shinfo(skb)->tx_flags); 2122 skb_shinfo(skb)->destructor_arg = ph.raw; 2123 2124 switch (po->tp_version) { 2125 case TPACKET_V2: 2126 tp_len = ph.h2->tp_len; 2127 break; 2128 default: 2129 tp_len = ph.h1->tp_len; 2130 break; 2131 } 2132 if (unlikely(tp_len > size_max)) { 2133 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max); 2134 return -EMSGSIZE; 2135 } 2136 2137 skb_reserve(skb, hlen); 2138 skb_reset_network_header(skb); 2139 2140 if (!packet_use_direct_xmit(po)) 2141 skb_probe_transport_header(skb, 0); 2142 if (unlikely(po->tp_tx_has_off)) { 2143 int off_min, off_max, off; 2144 off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll); 2145 off_max = po->tx_ring.frame_size - tp_len; 2146 if (sock->type == SOCK_DGRAM) { 2147 switch (po->tp_version) { 2148 case TPACKET_V2: 2149 off = ph.h2->tp_net; 2150 break; 2151 default: 2152 off = ph.h1->tp_net; 2153 break; 2154 } 2155 } else { 2156 switch (po->tp_version) { 2157 case TPACKET_V2: 2158 off = ph.h2->tp_mac; 2159 break; 2160 default: 2161 off = ph.h1->tp_mac; 2162 break; 2163 } 2164 } 2165 if (unlikely((off < off_min) || (off_max < off))) 2166 return -EINVAL; 2167 data = ph.raw + off; 2168 } else { 2169 data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll); 2170 } 2171 to_write = tp_len; 2172 2173 if (sock->type == SOCK_DGRAM) { 2174 err = dev_hard_header(skb, dev, ntohs(proto), addr, 2175 NULL, tp_len); 2176 if (unlikely(err < 0)) 2177 return -EINVAL; 2178 } else if (dev->hard_header_len) { 2179 /* net device doesn't like empty head */ 2180 if (unlikely(tp_len <= dev->hard_header_len)) { 2181 pr_err("packet size is too short (%d < %d)\n", 2182 tp_len, dev->hard_header_len); 2183 return -EINVAL; 2184 } 2185 2186 skb_push(skb, dev->hard_header_len); 2187 err = skb_store_bits(skb, 0, data, 2188 dev->hard_header_len); 2189 if (unlikely(err)) 2190 return err; 2191 2192 data += dev->hard_header_len; 2193 to_write -= dev->hard_header_len; 2194 } 2195 2196 offset = offset_in_page(data); 2197 len_max = PAGE_SIZE - offset; 2198 len = ((to_write > len_max) ? len_max : to_write); 2199 2200 skb->data_len = to_write; 2201 skb->len += to_write; 2202 skb->truesize += to_write; 2203 atomic_add(to_write, &po->sk.sk_wmem_alloc); 2204 2205 while (likely(to_write)) { 2206 nr_frags = skb_shinfo(skb)->nr_frags; 2207 2208 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) { 2209 pr_err("Packet exceed the number of skb frags(%lu)\n", 2210 MAX_SKB_FRAGS); 2211 return -EFAULT; 2212 } 2213 2214 page = pgv_to_page(data); 2215 data += len; 2216 flush_dcache_page(page); 2217 get_page(page); 2218 skb_fill_page_desc(skb, nr_frags, page, offset, len); 2219 to_write -= len; 2220 offset = 0; 2221 len_max = PAGE_SIZE; 2222 len = ((to_write > len_max) ? len_max : to_write); 2223 } 2224 2225 return tp_len; 2226 } 2227 2228 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg) 2229 { 2230 struct sk_buff *skb; 2231 struct net_device *dev; 2232 __be16 proto; 2233 int err, reserve = 0; 2234 void *ph; 2235 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name); 2236 bool need_wait = !(msg->msg_flags & MSG_DONTWAIT); 2237 int tp_len, size_max; 2238 unsigned char *addr; 2239 int len_sum = 0; 2240 int status = TP_STATUS_AVAILABLE; 2241 int hlen, tlen; 2242 2243 mutex_lock(&po->pg_vec_lock); 2244 2245 if (likely(saddr == NULL)) { 2246 dev = packet_cached_dev_get(po); 2247 proto = po->num; 2248 addr = NULL; 2249 } else { 2250 err = -EINVAL; 2251 if (msg->msg_namelen < sizeof(struct sockaddr_ll)) 2252 goto out; 2253 if (msg->msg_namelen < (saddr->sll_halen 2254 + offsetof(struct sockaddr_ll, 2255 sll_addr))) 2256 goto out; 2257 proto = saddr->sll_protocol; 2258 addr = saddr->sll_addr; 2259 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex); 2260 } 2261 2262 err = -ENXIO; 2263 if (unlikely(dev == NULL)) 2264 goto out; 2265 err = -ENETDOWN; 2266 if (unlikely(!(dev->flags & IFF_UP))) 2267 goto out_put; 2268 2269 reserve = dev->hard_header_len + VLAN_HLEN; 2270 size_max = po->tx_ring.frame_size 2271 - (po->tp_hdrlen - sizeof(struct sockaddr_ll)); 2272 2273 if (size_max > dev->mtu + reserve) 2274 size_max = dev->mtu + reserve; 2275 2276 do { 2277 ph = packet_current_frame(po, &po->tx_ring, 2278 TP_STATUS_SEND_REQUEST); 2279 if (unlikely(ph == NULL)) { 2280 if (need_wait && need_resched()) 2281 schedule(); 2282 continue; 2283 } 2284 2285 status = TP_STATUS_SEND_REQUEST; 2286 hlen = LL_RESERVED_SPACE(dev); 2287 tlen = dev->needed_tailroom; 2288 skb = sock_alloc_send_skb(&po->sk, 2289 hlen + tlen + sizeof(struct sockaddr_ll), 2290 0, &err); 2291 2292 if (unlikely(skb == NULL)) 2293 goto out_status; 2294 2295 tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto, 2296 addr, hlen); 2297 if (tp_len > dev->mtu + dev->hard_header_len) { 2298 struct ethhdr *ehdr; 2299 /* Earlier code assumed this would be a VLAN pkt, 2300 * double-check this now that we have the actual 2301 * packet in hand. 2302 */ 2303 2304 skb_reset_mac_header(skb); 2305 ehdr = eth_hdr(skb); 2306 if (ehdr->h_proto != htons(ETH_P_8021Q)) 2307 tp_len = -EMSGSIZE; 2308 } 2309 if (unlikely(tp_len < 0)) { 2310 if (po->tp_loss) { 2311 __packet_set_status(po, ph, 2312 TP_STATUS_AVAILABLE); 2313 packet_increment_head(&po->tx_ring); 2314 kfree_skb(skb); 2315 continue; 2316 } else { 2317 status = TP_STATUS_WRONG_FORMAT; 2318 err = tp_len; 2319 goto out_status; 2320 } 2321 } 2322 2323 packet_pick_tx_queue(dev, skb); 2324 2325 skb->destructor = tpacket_destruct_skb; 2326 __packet_set_status(po, ph, TP_STATUS_SENDING); 2327 packet_inc_pending(&po->tx_ring); 2328 2329 status = TP_STATUS_SEND_REQUEST; 2330 err = po->xmit(skb); 2331 if (unlikely(err > 0)) { 2332 err = net_xmit_errno(err); 2333 if (err && __packet_get_status(po, ph) == 2334 TP_STATUS_AVAILABLE) { 2335 /* skb was destructed already */ 2336 skb = NULL; 2337 goto out_status; 2338 } 2339 /* 2340 * skb was dropped but not destructed yet; 2341 * let's treat it like congestion or err < 0 2342 */ 2343 err = 0; 2344 } 2345 packet_increment_head(&po->tx_ring); 2346 len_sum += tp_len; 2347 } while (likely((ph != NULL) || 2348 /* Note: packet_read_pending() might be slow if we have 2349 * to call it as it's per_cpu variable, but in fast-path 2350 * we already short-circuit the loop with the first 2351 * condition, and luckily don't have to go that path 2352 * anyway. 2353 */ 2354 (need_wait && packet_read_pending(&po->tx_ring)))); 2355 2356 err = len_sum; 2357 goto out_put; 2358 2359 out_status: 2360 __packet_set_status(po, ph, status); 2361 kfree_skb(skb); 2362 out_put: 2363 dev_put(dev); 2364 out: 2365 mutex_unlock(&po->pg_vec_lock); 2366 return err; 2367 } 2368 2369 static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad, 2370 size_t reserve, size_t len, 2371 size_t linear, int noblock, 2372 int *err) 2373 { 2374 struct sk_buff *skb; 2375 2376 /* Under a page? Don't bother with paged skb. */ 2377 if (prepad + len < PAGE_SIZE || !linear) 2378 linear = len; 2379 2380 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock, 2381 err, 0); 2382 if (!skb) 2383 return NULL; 2384 2385 skb_reserve(skb, reserve); 2386 skb_put(skb, linear); 2387 skb->data_len = len - linear; 2388 skb->len += len - linear; 2389 2390 return skb; 2391 } 2392 2393 static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len) 2394 { 2395 struct sock *sk = sock->sk; 2396 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name); 2397 struct sk_buff *skb; 2398 struct net_device *dev; 2399 __be16 proto; 2400 unsigned char *addr; 2401 int err, reserve = 0; 2402 struct virtio_net_hdr vnet_hdr = { 0 }; 2403 int offset = 0; 2404 int vnet_hdr_len; 2405 struct packet_sock *po = pkt_sk(sk); 2406 unsigned short gso_type = 0; 2407 int hlen, tlen; 2408 int extra_len = 0; 2409 2410 /* 2411 * Get and verify the address. 2412 */ 2413 2414 if (likely(saddr == NULL)) { 2415 dev = packet_cached_dev_get(po); 2416 proto = po->num; 2417 addr = NULL; 2418 } else { 2419 err = -EINVAL; 2420 if (msg->msg_namelen < sizeof(struct sockaddr_ll)) 2421 goto out; 2422 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr))) 2423 goto out; 2424 proto = saddr->sll_protocol; 2425 addr = saddr->sll_addr; 2426 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex); 2427 } 2428 2429 err = -ENXIO; 2430 if (unlikely(dev == NULL)) 2431 goto out_unlock; 2432 err = -ENETDOWN; 2433 if (unlikely(!(dev->flags & IFF_UP))) 2434 goto out_unlock; 2435 2436 if (sock->type == SOCK_RAW) 2437 reserve = dev->hard_header_len; 2438 if (po->has_vnet_hdr) { 2439 vnet_hdr_len = sizeof(vnet_hdr); 2440 2441 err = -EINVAL; 2442 if (len < vnet_hdr_len) 2443 goto out_unlock; 2444 2445 len -= vnet_hdr_len; 2446 2447 err = memcpy_fromiovec((void *)&vnet_hdr, msg->msg_iov, 2448 vnet_hdr_len); 2449 if (err < 0) 2450 goto out_unlock; 2451 2452 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && 2453 (vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 > 2454 vnet_hdr.hdr_len)) 2455 vnet_hdr.hdr_len = vnet_hdr.csum_start + 2456 vnet_hdr.csum_offset + 2; 2457 2458 err = -EINVAL; 2459 if (vnet_hdr.hdr_len > len) 2460 goto out_unlock; 2461 2462 if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) { 2463 switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { 2464 case VIRTIO_NET_HDR_GSO_TCPV4: 2465 gso_type = SKB_GSO_TCPV4; 2466 break; 2467 case VIRTIO_NET_HDR_GSO_TCPV6: 2468 gso_type = SKB_GSO_TCPV6; 2469 break; 2470 case VIRTIO_NET_HDR_GSO_UDP: 2471 gso_type = SKB_GSO_UDP; 2472 break; 2473 default: 2474 goto out_unlock; 2475 } 2476 2477 if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN) 2478 gso_type |= SKB_GSO_TCP_ECN; 2479 2480 if (vnet_hdr.gso_size == 0) 2481 goto out_unlock; 2482 2483 } 2484 } 2485 2486 if (unlikely(sock_flag(sk, SOCK_NOFCS))) { 2487 if (!netif_supports_nofcs(dev)) { 2488 err = -EPROTONOSUPPORT; 2489 goto out_unlock; 2490 } 2491 extra_len = 4; /* We're doing our own CRC */ 2492 } 2493 2494 err = -EMSGSIZE; 2495 if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN + extra_len)) 2496 goto out_unlock; 2497 2498 err = -ENOBUFS; 2499 hlen = LL_RESERVED_SPACE(dev); 2500 tlen = dev->needed_tailroom; 2501 skb = packet_alloc_skb(sk, hlen + tlen, hlen, len, vnet_hdr.hdr_len, 2502 msg->msg_flags & MSG_DONTWAIT, &err); 2503 if (skb == NULL) 2504 goto out_unlock; 2505 2506 skb_set_network_header(skb, reserve); 2507 2508 err = -EINVAL; 2509 if (sock->type == SOCK_DGRAM && 2510 (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0) 2511 goto out_free; 2512 2513 /* Returns -EFAULT on error */ 2514 err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len); 2515 if (err) 2516 goto out_free; 2517 2518 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags); 2519 2520 if (!gso_type && (len > dev->mtu + reserve + extra_len)) { 2521 /* Earlier code assumed this would be a VLAN pkt, 2522 * double-check this now that we have the actual 2523 * packet in hand. 2524 */ 2525 struct ethhdr *ehdr; 2526 skb_reset_mac_header(skb); 2527 ehdr = eth_hdr(skb); 2528 if (ehdr->h_proto != htons(ETH_P_8021Q)) { 2529 err = -EMSGSIZE; 2530 goto out_free; 2531 } 2532 } 2533 2534 skb->protocol = proto; 2535 skb->dev = dev; 2536 skb->priority = sk->sk_priority; 2537 skb->mark = sk->sk_mark; 2538 2539 packet_pick_tx_queue(dev, skb); 2540 2541 if (po->has_vnet_hdr) { 2542 if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) { 2543 if (!skb_partial_csum_set(skb, vnet_hdr.csum_start, 2544 vnet_hdr.csum_offset)) { 2545 err = -EINVAL; 2546 goto out_free; 2547 } 2548 } 2549 2550 skb_shinfo(skb)->gso_size = vnet_hdr.gso_size; 2551 skb_shinfo(skb)->gso_type = gso_type; 2552 2553 /* Header must be checked, and gso_segs computed. */ 2554 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY; 2555 skb_shinfo(skb)->gso_segs = 0; 2556 2557 len += vnet_hdr_len; 2558 } 2559 2560 if (!packet_use_direct_xmit(po)) 2561 skb_probe_transport_header(skb, reserve); 2562 if (unlikely(extra_len == 4)) 2563 skb->no_fcs = 1; 2564 2565 err = po->xmit(skb); 2566 if (err > 0 && (err = net_xmit_errno(err)) != 0) 2567 goto out_unlock; 2568 2569 dev_put(dev); 2570 2571 return len; 2572 2573 out_free: 2574 kfree_skb(skb); 2575 out_unlock: 2576 if (dev) 2577 dev_put(dev); 2578 out: 2579 return err; 2580 } 2581 2582 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock, 2583 struct msghdr *msg, size_t len) 2584 { 2585 struct sock *sk = sock->sk; 2586 struct packet_sock *po = pkt_sk(sk); 2587 2588 if (po->tx_ring.pg_vec) 2589 return tpacket_snd(po, msg); 2590 else 2591 return packet_snd(sock, msg, len); 2592 } 2593 2594 /* 2595 * Close a PACKET socket. This is fairly simple. We immediately go 2596 * to 'closed' state and remove our protocol entry in the device list. 2597 */ 2598 2599 static int packet_release(struct socket *sock) 2600 { 2601 struct sock *sk = sock->sk; 2602 struct packet_sock *po; 2603 struct net *net; 2604 union tpacket_req_u req_u; 2605 2606 if (!sk) 2607 return 0; 2608 2609 net = sock_net(sk); 2610 po = pkt_sk(sk); 2611 2612 mutex_lock(&net->packet.sklist_lock); 2613 sk_del_node_init_rcu(sk); 2614 mutex_unlock(&net->packet.sklist_lock); 2615 2616 preempt_disable(); 2617 sock_prot_inuse_add(net, sk->sk_prot, -1); 2618 preempt_enable(); 2619 2620 spin_lock(&po->bind_lock); 2621 unregister_prot_hook(sk, false); 2622 packet_cached_dev_reset(po); 2623 2624 if (po->prot_hook.dev) { 2625 dev_put(po->prot_hook.dev); 2626 po->prot_hook.dev = NULL; 2627 } 2628 spin_unlock(&po->bind_lock); 2629 2630 packet_flush_mclist(sk); 2631 2632 if (po->rx_ring.pg_vec) { 2633 memset(&req_u, 0, sizeof(req_u)); 2634 packet_set_ring(sk, &req_u, 1, 0); 2635 } 2636 2637 if (po->tx_ring.pg_vec) { 2638 memset(&req_u, 0, sizeof(req_u)); 2639 packet_set_ring(sk, &req_u, 1, 1); 2640 } 2641 2642 fanout_release(sk); 2643 2644 synchronize_net(); 2645 /* 2646 * Now the socket is dead. No more input will appear. 2647 */ 2648 sock_orphan(sk); 2649 sock->sk = NULL; 2650 2651 /* Purge queues */ 2652 2653 skb_queue_purge(&sk->sk_receive_queue); 2654 packet_free_pending(po); 2655 sk_refcnt_debug_release(sk); 2656 2657 sock_put(sk); 2658 return 0; 2659 } 2660 2661 /* 2662 * Attach a packet hook. 2663 */ 2664 2665 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 proto) 2666 { 2667 struct packet_sock *po = pkt_sk(sk); 2668 const struct net_device *dev_curr; 2669 __be16 proto_curr; 2670 bool need_rehook; 2671 2672 if (po->fanout) { 2673 if (dev) 2674 dev_put(dev); 2675 2676 return -EINVAL; 2677 } 2678 2679 lock_sock(sk); 2680 spin_lock(&po->bind_lock); 2681 2682 proto_curr = po->prot_hook.type; 2683 dev_curr = po->prot_hook.dev; 2684 2685 need_rehook = proto_curr != proto || dev_curr != dev; 2686 2687 if (need_rehook) { 2688 unregister_prot_hook(sk, true); 2689 2690 po->num = proto; 2691 po->prot_hook.type = proto; 2692 2693 if (po->prot_hook.dev) 2694 dev_put(po->prot_hook.dev); 2695 2696 po->prot_hook.dev = dev; 2697 2698 po->ifindex = dev ? dev->ifindex : 0; 2699 packet_cached_dev_assign(po, dev); 2700 } 2701 2702 if (proto == 0 || !need_rehook) 2703 goto out_unlock; 2704 2705 if (!dev || (dev->flags & IFF_UP)) { 2706 register_prot_hook(sk); 2707 } else { 2708 sk->sk_err = ENETDOWN; 2709 if (!sock_flag(sk, SOCK_DEAD)) 2710 sk->sk_error_report(sk); 2711 } 2712 2713 out_unlock: 2714 spin_unlock(&po->bind_lock); 2715 release_sock(sk); 2716 return 0; 2717 } 2718 2719 /* 2720 * Bind a packet socket to a device 2721 */ 2722 2723 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr, 2724 int addr_len) 2725 { 2726 struct sock *sk = sock->sk; 2727 char name[15]; 2728 struct net_device *dev; 2729 int err = -ENODEV; 2730 2731 /* 2732 * Check legality 2733 */ 2734 2735 if (addr_len != sizeof(struct sockaddr)) 2736 return -EINVAL; 2737 strlcpy(name, uaddr->sa_data, sizeof(name)); 2738 2739 dev = dev_get_by_name(sock_net(sk), name); 2740 if (dev) 2741 err = packet_do_bind(sk, dev, pkt_sk(sk)->num); 2742 return err; 2743 } 2744 2745 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) 2746 { 2747 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr; 2748 struct sock *sk = sock->sk; 2749 struct net_device *dev = NULL; 2750 int err; 2751 2752 2753 /* 2754 * Check legality 2755 */ 2756 2757 if (addr_len < sizeof(struct sockaddr_ll)) 2758 return -EINVAL; 2759 if (sll->sll_family != AF_PACKET) 2760 return -EINVAL; 2761 2762 if (sll->sll_ifindex) { 2763 err = -ENODEV; 2764 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex); 2765 if (dev == NULL) 2766 goto out; 2767 } 2768 err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num); 2769 2770 out: 2771 return err; 2772 } 2773 2774 static struct proto packet_proto = { 2775 .name = "PACKET", 2776 .owner = THIS_MODULE, 2777 .obj_size = sizeof(struct packet_sock), 2778 }; 2779 2780 /* 2781 * Create a packet of type SOCK_PACKET. 2782 */ 2783 2784 static int packet_create(struct net *net, struct socket *sock, int protocol, 2785 int kern) 2786 { 2787 struct sock *sk; 2788 struct packet_sock *po; 2789 __be16 proto = (__force __be16)protocol; /* weird, but documented */ 2790 int err; 2791 2792 if (!ns_capable(net->user_ns, CAP_NET_RAW)) 2793 return -EPERM; 2794 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW && 2795 sock->type != SOCK_PACKET) 2796 return -ESOCKTNOSUPPORT; 2797 2798 sock->state = SS_UNCONNECTED; 2799 2800 err = -ENOBUFS; 2801 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto); 2802 if (sk == NULL) 2803 goto out; 2804 2805 sock->ops = &packet_ops; 2806 if (sock->type == SOCK_PACKET) 2807 sock->ops = &packet_ops_spkt; 2808 2809 sock_init_data(sock, sk); 2810 2811 po = pkt_sk(sk); 2812 sk->sk_family = PF_PACKET; 2813 po->num = proto; 2814 po->xmit = dev_queue_xmit; 2815 2816 err = packet_alloc_pending(po); 2817 if (err) 2818 goto out2; 2819 2820 packet_cached_dev_reset(po); 2821 2822 sk->sk_destruct = packet_sock_destruct; 2823 sk_refcnt_debug_inc(sk); 2824 2825 /* 2826 * Attach a protocol block 2827 */ 2828 2829 spin_lock_init(&po->bind_lock); 2830 mutex_init(&po->pg_vec_lock); 2831 po->prot_hook.func = packet_rcv; 2832 2833 if (sock->type == SOCK_PACKET) 2834 po->prot_hook.func = packet_rcv_spkt; 2835 2836 po->prot_hook.af_packet_priv = sk; 2837 2838 if (proto) { 2839 po->prot_hook.type = proto; 2840 register_prot_hook(sk); 2841 } 2842 2843 mutex_lock(&net->packet.sklist_lock); 2844 sk_add_node_rcu(sk, &net->packet.sklist); 2845 mutex_unlock(&net->packet.sklist_lock); 2846 2847 preempt_disable(); 2848 sock_prot_inuse_add(net, &packet_proto, 1); 2849 preempt_enable(); 2850 2851 return 0; 2852 out2: 2853 sk_free(sk); 2854 out: 2855 return err; 2856 } 2857 2858 /* 2859 * Pull a packet from our receive queue and hand it to the user. 2860 * If necessary we block. 2861 */ 2862 2863 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock, 2864 struct msghdr *msg, size_t len, int flags) 2865 { 2866 struct sock *sk = sock->sk; 2867 struct sk_buff *skb; 2868 int copied, err; 2869 int vnet_hdr_len = 0; 2870 2871 err = -EINVAL; 2872 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE)) 2873 goto out; 2874 2875 #if 0 2876 /* What error should we return now? EUNATTACH? */ 2877 if (pkt_sk(sk)->ifindex < 0) 2878 return -ENODEV; 2879 #endif 2880 2881 if (flags & MSG_ERRQUEUE) { 2882 err = sock_recv_errqueue(sk, msg, len, 2883 SOL_PACKET, PACKET_TX_TIMESTAMP); 2884 goto out; 2885 } 2886 2887 /* 2888 * Call the generic datagram receiver. This handles all sorts 2889 * of horrible races and re-entrancy so we can forget about it 2890 * in the protocol layers. 2891 * 2892 * Now it will return ENETDOWN, if device have just gone down, 2893 * but then it will block. 2894 */ 2895 2896 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err); 2897 2898 /* 2899 * An error occurred so return it. Because skb_recv_datagram() 2900 * handles the blocking we don't see and worry about blocking 2901 * retries. 2902 */ 2903 2904 if (skb == NULL) 2905 goto out; 2906 2907 if (pkt_sk(sk)->has_vnet_hdr) { 2908 struct virtio_net_hdr vnet_hdr = { 0 }; 2909 2910 err = -EINVAL; 2911 vnet_hdr_len = sizeof(vnet_hdr); 2912 if (len < vnet_hdr_len) 2913 goto out_free; 2914 2915 len -= vnet_hdr_len; 2916 2917 if (skb_is_gso(skb)) { 2918 struct skb_shared_info *sinfo = skb_shinfo(skb); 2919 2920 /* This is a hint as to how much should be linear. */ 2921 vnet_hdr.hdr_len = skb_headlen(skb); 2922 vnet_hdr.gso_size = sinfo->gso_size; 2923 if (sinfo->gso_type & SKB_GSO_TCPV4) 2924 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4; 2925 else if (sinfo->gso_type & SKB_GSO_TCPV6) 2926 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6; 2927 else if (sinfo->gso_type & SKB_GSO_UDP) 2928 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP; 2929 else if (sinfo->gso_type & SKB_GSO_FCOE) 2930 goto out_free; 2931 else 2932 BUG(); 2933 if (sinfo->gso_type & SKB_GSO_TCP_ECN) 2934 vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN; 2935 } else 2936 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE; 2937 2938 if (skb->ip_summed == CHECKSUM_PARTIAL) { 2939 vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; 2940 vnet_hdr.csum_start = skb_checksum_start_offset(skb); 2941 vnet_hdr.csum_offset = skb->csum_offset; 2942 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) { 2943 vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID; 2944 } /* else everything is zero */ 2945 2946 err = memcpy_toiovec(msg->msg_iov, (void *)&vnet_hdr, 2947 vnet_hdr_len); 2948 if (err < 0) 2949 goto out_free; 2950 } 2951 2952 /* You lose any data beyond the buffer you gave. If it worries 2953 * a user program they can ask the device for its MTU 2954 * anyway. 2955 */ 2956 copied = skb->len; 2957 if (copied > len) { 2958 copied = len; 2959 msg->msg_flags |= MSG_TRUNC; 2960 } 2961 2962 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); 2963 if (err) 2964 goto out_free; 2965 2966 sock_recv_ts_and_drops(msg, sk, skb); 2967 2968 if (msg->msg_name) { 2969 /* If the address length field is there to be filled 2970 * in, we fill it in now. 2971 */ 2972 if (sock->type == SOCK_PACKET) { 2973 __sockaddr_check_size(sizeof(struct sockaddr_pkt)); 2974 msg->msg_namelen = sizeof(struct sockaddr_pkt); 2975 } else { 2976 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll; 2977 msg->msg_namelen = sll->sll_halen + 2978 offsetof(struct sockaddr_ll, sll_addr); 2979 } 2980 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa, 2981 msg->msg_namelen); 2982 } 2983 2984 if (pkt_sk(sk)->auxdata) { 2985 struct tpacket_auxdata aux; 2986 2987 aux.tp_status = TP_STATUS_USER; 2988 if (skb->ip_summed == CHECKSUM_PARTIAL) 2989 aux.tp_status |= TP_STATUS_CSUMNOTREADY; 2990 aux.tp_len = PACKET_SKB_CB(skb)->origlen; 2991 aux.tp_snaplen = skb->len; 2992 aux.tp_mac = 0; 2993 aux.tp_net = skb_network_offset(skb); 2994 if (vlan_tx_tag_present(skb)) { 2995 aux.tp_vlan_tci = vlan_tx_tag_get(skb); 2996 aux.tp_vlan_tpid = ntohs(skb->vlan_proto); 2997 aux.tp_status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID; 2998 } else { 2999 aux.tp_vlan_tci = 0; 3000 aux.tp_vlan_tpid = 0; 3001 } 3002 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux); 3003 } 3004 3005 /* 3006 * Free or return the buffer as appropriate. Again this 3007 * hides all the races and re-entrancy issues from us. 3008 */ 3009 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied); 3010 3011 out_free: 3012 skb_free_datagram(sk, skb); 3013 out: 3014 return err; 3015 } 3016 3017 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr, 3018 int *uaddr_len, int peer) 3019 { 3020 struct net_device *dev; 3021 struct sock *sk = sock->sk; 3022 3023 if (peer) 3024 return -EOPNOTSUPP; 3025 3026 uaddr->sa_family = AF_PACKET; 3027 memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data)); 3028 rcu_read_lock(); 3029 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex); 3030 if (dev) 3031 strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data)); 3032 rcu_read_unlock(); 3033 *uaddr_len = sizeof(*uaddr); 3034 3035 return 0; 3036 } 3037 3038 static int packet_getname(struct socket *sock, struct sockaddr *uaddr, 3039 int *uaddr_len, int peer) 3040 { 3041 struct net_device *dev; 3042 struct sock *sk = sock->sk; 3043 struct packet_sock *po = pkt_sk(sk); 3044 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr); 3045 3046 if (peer) 3047 return -EOPNOTSUPP; 3048 3049 sll->sll_family = AF_PACKET; 3050 sll->sll_ifindex = po->ifindex; 3051 sll->sll_protocol = po->num; 3052 sll->sll_pkttype = 0; 3053 rcu_read_lock(); 3054 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex); 3055 if (dev) { 3056 sll->sll_hatype = dev->type; 3057 sll->sll_halen = dev->addr_len; 3058 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len); 3059 } else { 3060 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */ 3061 sll->sll_halen = 0; 3062 } 3063 rcu_read_unlock(); 3064 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen; 3065 3066 return 0; 3067 } 3068 3069 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i, 3070 int what) 3071 { 3072 switch (i->type) { 3073 case PACKET_MR_MULTICAST: 3074 if (i->alen != dev->addr_len) 3075 return -EINVAL; 3076 if (what > 0) 3077 return dev_mc_add(dev, i->addr); 3078 else 3079 return dev_mc_del(dev, i->addr); 3080 break; 3081 case PACKET_MR_PROMISC: 3082 return dev_set_promiscuity(dev, what); 3083 case PACKET_MR_ALLMULTI: 3084 return dev_set_allmulti(dev, what); 3085 case PACKET_MR_UNICAST: 3086 if (i->alen != dev->addr_len) 3087 return -EINVAL; 3088 if (what > 0) 3089 return dev_uc_add(dev, i->addr); 3090 else 3091 return dev_uc_del(dev, i->addr); 3092 break; 3093 default: 3094 break; 3095 } 3096 return 0; 3097 } 3098 3099 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what) 3100 { 3101 for ( ; i; i = i->next) { 3102 if (i->ifindex == dev->ifindex) 3103 packet_dev_mc(dev, i, what); 3104 } 3105 } 3106 3107 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq) 3108 { 3109 struct packet_sock *po = pkt_sk(sk); 3110 struct packet_mclist *ml, *i; 3111 struct net_device *dev; 3112 int err; 3113 3114 rtnl_lock(); 3115 3116 err = -ENODEV; 3117 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex); 3118 if (!dev) 3119 goto done; 3120 3121 err = -EINVAL; 3122 if (mreq->mr_alen > dev->addr_len) 3123 goto done; 3124 3125 err = -ENOBUFS; 3126 i = kmalloc(sizeof(*i), GFP_KERNEL); 3127 if (i == NULL) 3128 goto done; 3129 3130 err = 0; 3131 for (ml = po->mclist; ml; ml = ml->next) { 3132 if (ml->ifindex == mreq->mr_ifindex && 3133 ml->type == mreq->mr_type && 3134 ml->alen == mreq->mr_alen && 3135 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) { 3136 ml->count++; 3137 /* Free the new element ... */ 3138 kfree(i); 3139 goto done; 3140 } 3141 } 3142 3143 i->type = mreq->mr_type; 3144 i->ifindex = mreq->mr_ifindex; 3145 i->alen = mreq->mr_alen; 3146 memcpy(i->addr, mreq->mr_address, i->alen); 3147 i->count = 1; 3148 i->next = po->mclist; 3149 po->mclist = i; 3150 err = packet_dev_mc(dev, i, 1); 3151 if (err) { 3152 po->mclist = i->next; 3153 kfree(i); 3154 } 3155 3156 done: 3157 rtnl_unlock(); 3158 return err; 3159 } 3160 3161 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq) 3162 { 3163 struct packet_mclist *ml, **mlp; 3164 3165 rtnl_lock(); 3166 3167 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) { 3168 if (ml->ifindex == mreq->mr_ifindex && 3169 ml->type == mreq->mr_type && 3170 ml->alen == mreq->mr_alen && 3171 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) { 3172 if (--ml->count == 0) { 3173 struct net_device *dev; 3174 *mlp = ml->next; 3175 dev = __dev_get_by_index(sock_net(sk), ml->ifindex); 3176 if (dev) 3177 packet_dev_mc(dev, ml, -1); 3178 kfree(ml); 3179 } 3180 rtnl_unlock(); 3181 return 0; 3182 } 3183 } 3184 rtnl_unlock(); 3185 return -EADDRNOTAVAIL; 3186 } 3187 3188 static void packet_flush_mclist(struct sock *sk) 3189 { 3190 struct packet_sock *po = pkt_sk(sk); 3191 struct packet_mclist *ml; 3192 3193 if (!po->mclist) 3194 return; 3195 3196 rtnl_lock(); 3197 while ((ml = po->mclist) != NULL) { 3198 struct net_device *dev; 3199 3200 po->mclist = ml->next; 3201 dev = __dev_get_by_index(sock_net(sk), ml->ifindex); 3202 if (dev != NULL) 3203 packet_dev_mc(dev, ml, -1); 3204 kfree(ml); 3205 } 3206 rtnl_unlock(); 3207 } 3208 3209 static int 3210 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen) 3211 { 3212 struct sock *sk = sock->sk; 3213 struct packet_sock *po = pkt_sk(sk); 3214 int ret; 3215 3216 if (level != SOL_PACKET) 3217 return -ENOPROTOOPT; 3218 3219 switch (optname) { 3220 case PACKET_ADD_MEMBERSHIP: 3221 case PACKET_DROP_MEMBERSHIP: 3222 { 3223 struct packet_mreq_max mreq; 3224 int len = optlen; 3225 memset(&mreq, 0, sizeof(mreq)); 3226 if (len < sizeof(struct packet_mreq)) 3227 return -EINVAL; 3228 if (len > sizeof(mreq)) 3229 len = sizeof(mreq); 3230 if (copy_from_user(&mreq, optval, len)) 3231 return -EFAULT; 3232 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address))) 3233 return -EINVAL; 3234 if (optname == PACKET_ADD_MEMBERSHIP) 3235 ret = packet_mc_add(sk, &mreq); 3236 else 3237 ret = packet_mc_drop(sk, &mreq); 3238 return ret; 3239 } 3240 3241 case PACKET_RX_RING: 3242 case PACKET_TX_RING: 3243 { 3244 union tpacket_req_u req_u; 3245 int len; 3246 3247 switch (po->tp_version) { 3248 case TPACKET_V1: 3249 case TPACKET_V2: 3250 len = sizeof(req_u.req); 3251 break; 3252 case TPACKET_V3: 3253 default: 3254 len = sizeof(req_u.req3); 3255 break; 3256 } 3257 if (optlen < len) 3258 return -EINVAL; 3259 if (pkt_sk(sk)->has_vnet_hdr) 3260 return -EINVAL; 3261 if (copy_from_user(&req_u.req, optval, len)) 3262 return -EFAULT; 3263 return packet_set_ring(sk, &req_u, 0, 3264 optname == PACKET_TX_RING); 3265 } 3266 case PACKET_COPY_THRESH: 3267 { 3268 int val; 3269 3270 if (optlen != sizeof(val)) 3271 return -EINVAL; 3272 if (copy_from_user(&val, optval, sizeof(val))) 3273 return -EFAULT; 3274 3275 pkt_sk(sk)->copy_thresh = val; 3276 return 0; 3277 } 3278 case PACKET_VERSION: 3279 { 3280 int val; 3281 3282 if (optlen != sizeof(val)) 3283 return -EINVAL; 3284 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 3285 return -EBUSY; 3286 if (copy_from_user(&val, optval, sizeof(val))) 3287 return -EFAULT; 3288 switch (val) { 3289 case TPACKET_V1: 3290 case TPACKET_V2: 3291 case TPACKET_V3: 3292 po->tp_version = val; 3293 return 0; 3294 default: 3295 return -EINVAL; 3296 } 3297 } 3298 case PACKET_RESERVE: 3299 { 3300 unsigned int val; 3301 3302 if (optlen != sizeof(val)) 3303 return -EINVAL; 3304 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 3305 return -EBUSY; 3306 if (copy_from_user(&val, optval, sizeof(val))) 3307 return -EFAULT; 3308 po->tp_reserve = val; 3309 return 0; 3310 } 3311 case PACKET_LOSS: 3312 { 3313 unsigned int val; 3314 3315 if (optlen != sizeof(val)) 3316 return -EINVAL; 3317 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 3318 return -EBUSY; 3319 if (copy_from_user(&val, optval, sizeof(val))) 3320 return -EFAULT; 3321 po->tp_loss = !!val; 3322 return 0; 3323 } 3324 case PACKET_AUXDATA: 3325 { 3326 int val; 3327 3328 if (optlen < sizeof(val)) 3329 return -EINVAL; 3330 if (copy_from_user(&val, optval, sizeof(val))) 3331 return -EFAULT; 3332 3333 po->auxdata = !!val; 3334 return 0; 3335 } 3336 case PACKET_ORIGDEV: 3337 { 3338 int val; 3339 3340 if (optlen < sizeof(val)) 3341 return -EINVAL; 3342 if (copy_from_user(&val, optval, sizeof(val))) 3343 return -EFAULT; 3344 3345 po->origdev = !!val; 3346 return 0; 3347 } 3348 case PACKET_VNET_HDR: 3349 { 3350 int val; 3351 3352 if (sock->type != SOCK_RAW) 3353 return -EINVAL; 3354 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 3355 return -EBUSY; 3356 if (optlen < sizeof(val)) 3357 return -EINVAL; 3358 if (copy_from_user(&val, optval, sizeof(val))) 3359 return -EFAULT; 3360 3361 po->has_vnet_hdr = !!val; 3362 return 0; 3363 } 3364 case PACKET_TIMESTAMP: 3365 { 3366 int val; 3367 3368 if (optlen != sizeof(val)) 3369 return -EINVAL; 3370 if (copy_from_user(&val, optval, sizeof(val))) 3371 return -EFAULT; 3372 3373 po->tp_tstamp = val; 3374 return 0; 3375 } 3376 case PACKET_FANOUT: 3377 { 3378 int val; 3379 3380 if (optlen != sizeof(val)) 3381 return -EINVAL; 3382 if (copy_from_user(&val, optval, sizeof(val))) 3383 return -EFAULT; 3384 3385 return fanout_add(sk, val & 0xffff, val >> 16); 3386 } 3387 case PACKET_TX_HAS_OFF: 3388 { 3389 unsigned int val; 3390 3391 if (optlen != sizeof(val)) 3392 return -EINVAL; 3393 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 3394 return -EBUSY; 3395 if (copy_from_user(&val, optval, sizeof(val))) 3396 return -EFAULT; 3397 po->tp_tx_has_off = !!val; 3398 return 0; 3399 } 3400 case PACKET_QDISC_BYPASS: 3401 { 3402 int val; 3403 3404 if (optlen != sizeof(val)) 3405 return -EINVAL; 3406 if (copy_from_user(&val, optval, sizeof(val))) 3407 return -EFAULT; 3408 3409 po->xmit = val ? packet_direct_xmit : dev_queue_xmit; 3410 return 0; 3411 } 3412 default: 3413 return -ENOPROTOOPT; 3414 } 3415 } 3416 3417 static int packet_getsockopt(struct socket *sock, int level, int optname, 3418 char __user *optval, int __user *optlen) 3419 { 3420 int len; 3421 int val, lv = sizeof(val); 3422 struct sock *sk = sock->sk; 3423 struct packet_sock *po = pkt_sk(sk); 3424 void *data = &val; 3425 union tpacket_stats_u st; 3426 3427 if (level != SOL_PACKET) 3428 return -ENOPROTOOPT; 3429 3430 if (get_user(len, optlen)) 3431 return -EFAULT; 3432 3433 if (len < 0) 3434 return -EINVAL; 3435 3436 switch (optname) { 3437 case PACKET_STATISTICS: 3438 spin_lock_bh(&sk->sk_receive_queue.lock); 3439 memcpy(&st, &po->stats, sizeof(st)); 3440 memset(&po->stats, 0, sizeof(po->stats)); 3441 spin_unlock_bh(&sk->sk_receive_queue.lock); 3442 3443 if (po->tp_version == TPACKET_V3) { 3444 lv = sizeof(struct tpacket_stats_v3); 3445 st.stats3.tp_packets += st.stats3.tp_drops; 3446 data = &st.stats3; 3447 } else { 3448 lv = sizeof(struct tpacket_stats); 3449 st.stats1.tp_packets += st.stats1.tp_drops; 3450 data = &st.stats1; 3451 } 3452 3453 break; 3454 case PACKET_AUXDATA: 3455 val = po->auxdata; 3456 break; 3457 case PACKET_ORIGDEV: 3458 val = po->origdev; 3459 break; 3460 case PACKET_VNET_HDR: 3461 val = po->has_vnet_hdr; 3462 break; 3463 case PACKET_VERSION: 3464 val = po->tp_version; 3465 break; 3466 case PACKET_HDRLEN: 3467 if (len > sizeof(int)) 3468 len = sizeof(int); 3469 if (copy_from_user(&val, optval, len)) 3470 return -EFAULT; 3471 switch (val) { 3472 case TPACKET_V1: 3473 val = sizeof(struct tpacket_hdr); 3474 break; 3475 case TPACKET_V2: 3476 val = sizeof(struct tpacket2_hdr); 3477 break; 3478 case TPACKET_V3: 3479 val = sizeof(struct tpacket3_hdr); 3480 break; 3481 default: 3482 return -EINVAL; 3483 } 3484 break; 3485 case PACKET_RESERVE: 3486 val = po->tp_reserve; 3487 break; 3488 case PACKET_LOSS: 3489 val = po->tp_loss; 3490 break; 3491 case PACKET_TIMESTAMP: 3492 val = po->tp_tstamp; 3493 break; 3494 case PACKET_FANOUT: 3495 val = (po->fanout ? 3496 ((u32)po->fanout->id | 3497 ((u32)po->fanout->type << 16) | 3498 ((u32)po->fanout->flags << 24)) : 3499 0); 3500 break; 3501 case PACKET_TX_HAS_OFF: 3502 val = po->tp_tx_has_off; 3503 break; 3504 case PACKET_QDISC_BYPASS: 3505 val = packet_use_direct_xmit(po); 3506 break; 3507 default: 3508 return -ENOPROTOOPT; 3509 } 3510 3511 if (len > lv) 3512 len = lv; 3513 if (put_user(len, optlen)) 3514 return -EFAULT; 3515 if (copy_to_user(optval, data, len)) 3516 return -EFAULT; 3517 return 0; 3518 } 3519 3520 3521 static int packet_notifier(struct notifier_block *this, 3522 unsigned long msg, void *ptr) 3523 { 3524 struct sock *sk; 3525 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 3526 struct net *net = dev_net(dev); 3527 3528 rcu_read_lock(); 3529 sk_for_each_rcu(sk, &net->packet.sklist) { 3530 struct packet_sock *po = pkt_sk(sk); 3531 3532 switch (msg) { 3533 case NETDEV_UNREGISTER: 3534 if (po->mclist) 3535 packet_dev_mclist(dev, po->mclist, -1); 3536 /* fallthrough */ 3537 3538 case NETDEV_DOWN: 3539 if (dev->ifindex == po->ifindex) { 3540 spin_lock(&po->bind_lock); 3541 if (po->running) { 3542 __unregister_prot_hook(sk, false); 3543 sk->sk_err = ENETDOWN; 3544 if (!sock_flag(sk, SOCK_DEAD)) 3545 sk->sk_error_report(sk); 3546 } 3547 if (msg == NETDEV_UNREGISTER) { 3548 packet_cached_dev_reset(po); 3549 po->ifindex = -1; 3550 if (po->prot_hook.dev) 3551 dev_put(po->prot_hook.dev); 3552 po->prot_hook.dev = NULL; 3553 } 3554 spin_unlock(&po->bind_lock); 3555 } 3556 break; 3557 case NETDEV_UP: 3558 if (dev->ifindex == po->ifindex) { 3559 spin_lock(&po->bind_lock); 3560 if (po->num) 3561 register_prot_hook(sk); 3562 spin_unlock(&po->bind_lock); 3563 } 3564 break; 3565 } 3566 } 3567 rcu_read_unlock(); 3568 return NOTIFY_DONE; 3569 } 3570 3571 3572 static int packet_ioctl(struct socket *sock, unsigned int cmd, 3573 unsigned long arg) 3574 { 3575 struct sock *sk = sock->sk; 3576 3577 switch (cmd) { 3578 case SIOCOUTQ: 3579 { 3580 int amount = sk_wmem_alloc_get(sk); 3581 3582 return put_user(amount, (int __user *)arg); 3583 } 3584 case SIOCINQ: 3585 { 3586 struct sk_buff *skb; 3587 int amount = 0; 3588 3589 spin_lock_bh(&sk->sk_receive_queue.lock); 3590 skb = skb_peek(&sk->sk_receive_queue); 3591 if (skb) 3592 amount = skb->len; 3593 spin_unlock_bh(&sk->sk_receive_queue.lock); 3594 return put_user(amount, (int __user *)arg); 3595 } 3596 case SIOCGSTAMP: 3597 return sock_get_timestamp(sk, (struct timeval __user *)arg); 3598 case SIOCGSTAMPNS: 3599 return sock_get_timestampns(sk, (struct timespec __user *)arg); 3600 3601 #ifdef CONFIG_INET 3602 case SIOCADDRT: 3603 case SIOCDELRT: 3604 case SIOCDARP: 3605 case SIOCGARP: 3606 case SIOCSARP: 3607 case SIOCGIFADDR: 3608 case SIOCSIFADDR: 3609 case SIOCGIFBRDADDR: 3610 case SIOCSIFBRDADDR: 3611 case SIOCGIFNETMASK: 3612 case SIOCSIFNETMASK: 3613 case SIOCGIFDSTADDR: 3614 case SIOCSIFDSTADDR: 3615 case SIOCSIFFLAGS: 3616 return inet_dgram_ops.ioctl(sock, cmd, arg); 3617 #endif 3618 3619 default: 3620 return -ENOIOCTLCMD; 3621 } 3622 return 0; 3623 } 3624 3625 static unsigned int packet_poll(struct file *file, struct socket *sock, 3626 poll_table *wait) 3627 { 3628 struct sock *sk = sock->sk; 3629 struct packet_sock *po = pkt_sk(sk); 3630 unsigned int mask = datagram_poll(file, sock, wait); 3631 3632 spin_lock_bh(&sk->sk_receive_queue.lock); 3633 if (po->rx_ring.pg_vec) { 3634 if (!packet_previous_rx_frame(po, &po->rx_ring, 3635 TP_STATUS_KERNEL)) 3636 mask |= POLLIN | POLLRDNORM; 3637 } 3638 spin_unlock_bh(&sk->sk_receive_queue.lock); 3639 spin_lock_bh(&sk->sk_write_queue.lock); 3640 if (po->tx_ring.pg_vec) { 3641 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE)) 3642 mask |= POLLOUT | POLLWRNORM; 3643 } 3644 spin_unlock_bh(&sk->sk_write_queue.lock); 3645 return mask; 3646 } 3647 3648 3649 /* Dirty? Well, I still did not learn better way to account 3650 * for user mmaps. 3651 */ 3652 3653 static void packet_mm_open(struct vm_area_struct *vma) 3654 { 3655 struct file *file = vma->vm_file; 3656 struct socket *sock = file->private_data; 3657 struct sock *sk = sock->sk; 3658 3659 if (sk) 3660 atomic_inc(&pkt_sk(sk)->mapped); 3661 } 3662 3663 static void packet_mm_close(struct vm_area_struct *vma) 3664 { 3665 struct file *file = vma->vm_file; 3666 struct socket *sock = file->private_data; 3667 struct sock *sk = sock->sk; 3668 3669 if (sk) 3670 atomic_dec(&pkt_sk(sk)->mapped); 3671 } 3672 3673 static const struct vm_operations_struct packet_mmap_ops = { 3674 .open = packet_mm_open, 3675 .close = packet_mm_close, 3676 }; 3677 3678 static void free_pg_vec(struct pgv *pg_vec, unsigned int order, 3679 unsigned int len) 3680 { 3681 int i; 3682 3683 for (i = 0; i < len; i++) { 3684 if (likely(pg_vec[i].buffer)) { 3685 if (is_vmalloc_addr(pg_vec[i].buffer)) 3686 vfree(pg_vec[i].buffer); 3687 else 3688 free_pages((unsigned long)pg_vec[i].buffer, 3689 order); 3690 pg_vec[i].buffer = NULL; 3691 } 3692 } 3693 kfree(pg_vec); 3694 } 3695 3696 static char *alloc_one_pg_vec_page(unsigned long order) 3697 { 3698 char *buffer; 3699 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP | 3700 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY; 3701 3702 buffer = (char *) __get_free_pages(gfp_flags, order); 3703 if (buffer) 3704 return buffer; 3705 3706 /* __get_free_pages failed, fall back to vmalloc */ 3707 buffer = vzalloc((1 << order) * PAGE_SIZE); 3708 if (buffer) 3709 return buffer; 3710 3711 /* vmalloc failed, lets dig into swap here */ 3712 gfp_flags &= ~__GFP_NORETRY; 3713 buffer = (char *) __get_free_pages(gfp_flags, order); 3714 if (buffer) 3715 return buffer; 3716 3717 /* complete and utter failure */ 3718 return NULL; 3719 } 3720 3721 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order) 3722 { 3723 unsigned int block_nr = req->tp_block_nr; 3724 struct pgv *pg_vec; 3725 int i; 3726 3727 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL); 3728 if (unlikely(!pg_vec)) 3729 goto out; 3730 3731 for (i = 0; i < block_nr; i++) { 3732 pg_vec[i].buffer = alloc_one_pg_vec_page(order); 3733 if (unlikely(!pg_vec[i].buffer)) 3734 goto out_free_pgvec; 3735 } 3736 3737 out: 3738 return pg_vec; 3739 3740 out_free_pgvec: 3741 free_pg_vec(pg_vec, order, block_nr); 3742 pg_vec = NULL; 3743 goto out; 3744 } 3745 3746 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u, 3747 int closing, int tx_ring) 3748 { 3749 struct pgv *pg_vec = NULL; 3750 struct packet_sock *po = pkt_sk(sk); 3751 int was_running, order = 0; 3752 struct packet_ring_buffer *rb; 3753 struct sk_buff_head *rb_queue; 3754 __be16 num; 3755 int err = -EINVAL; 3756 /* Added to avoid minimal code churn */ 3757 struct tpacket_req *req = &req_u->req; 3758 3759 /* Opening a Tx-ring is NOT supported in TPACKET_V3 */ 3760 if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) { 3761 WARN(1, "Tx-ring is not supported.\n"); 3762 goto out; 3763 } 3764 3765 rb = tx_ring ? &po->tx_ring : &po->rx_ring; 3766 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue; 3767 3768 err = -EBUSY; 3769 if (!closing) { 3770 if (atomic_read(&po->mapped)) 3771 goto out; 3772 if (packet_read_pending(rb)) 3773 goto out; 3774 } 3775 3776 if (req->tp_block_nr) { 3777 /* Sanity tests and some calculations */ 3778 err = -EBUSY; 3779 if (unlikely(rb->pg_vec)) 3780 goto out; 3781 3782 switch (po->tp_version) { 3783 case TPACKET_V1: 3784 po->tp_hdrlen = TPACKET_HDRLEN; 3785 break; 3786 case TPACKET_V2: 3787 po->tp_hdrlen = TPACKET2_HDRLEN; 3788 break; 3789 case TPACKET_V3: 3790 po->tp_hdrlen = TPACKET3_HDRLEN; 3791 break; 3792 } 3793 3794 err = -EINVAL; 3795 if (unlikely((int)req->tp_block_size <= 0)) 3796 goto out; 3797 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1))) 3798 goto out; 3799 if (po->tp_version >= TPACKET_V3 && 3800 (int)(req->tp_block_size - 3801 BLK_PLUS_PRIV(req_u->req3.tp_sizeof_priv)) <= 0) 3802 goto out; 3803 if (unlikely(req->tp_frame_size < po->tp_hdrlen + 3804 po->tp_reserve)) 3805 goto out; 3806 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1))) 3807 goto out; 3808 3809 rb->frames_per_block = req->tp_block_size/req->tp_frame_size; 3810 if (unlikely(rb->frames_per_block <= 0)) 3811 goto out; 3812 if (unlikely((rb->frames_per_block * req->tp_block_nr) != 3813 req->tp_frame_nr)) 3814 goto out; 3815 3816 err = -ENOMEM; 3817 order = get_order(req->tp_block_size); 3818 pg_vec = alloc_pg_vec(req, order); 3819 if (unlikely(!pg_vec)) 3820 goto out; 3821 switch (po->tp_version) { 3822 case TPACKET_V3: 3823 /* Transmit path is not supported. We checked 3824 * it above but just being paranoid 3825 */ 3826 if (!tx_ring) 3827 init_prb_bdqc(po, rb, pg_vec, req_u, tx_ring); 3828 break; 3829 default: 3830 break; 3831 } 3832 } 3833 /* Done */ 3834 else { 3835 err = -EINVAL; 3836 if (unlikely(req->tp_frame_nr)) 3837 goto out; 3838 } 3839 3840 lock_sock(sk); 3841 3842 /* Detach socket from network */ 3843 spin_lock(&po->bind_lock); 3844 was_running = po->running; 3845 num = po->num; 3846 if (was_running) { 3847 po->num = 0; 3848 __unregister_prot_hook(sk, false); 3849 } 3850 spin_unlock(&po->bind_lock); 3851 3852 synchronize_net(); 3853 3854 err = -EBUSY; 3855 mutex_lock(&po->pg_vec_lock); 3856 if (closing || atomic_read(&po->mapped) == 0) { 3857 err = 0; 3858 spin_lock_bh(&rb_queue->lock); 3859 swap(rb->pg_vec, pg_vec); 3860 rb->frame_max = (req->tp_frame_nr - 1); 3861 rb->head = 0; 3862 rb->frame_size = req->tp_frame_size; 3863 spin_unlock_bh(&rb_queue->lock); 3864 3865 swap(rb->pg_vec_order, order); 3866 swap(rb->pg_vec_len, req->tp_block_nr); 3867 3868 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE; 3869 po->prot_hook.func = (po->rx_ring.pg_vec) ? 3870 tpacket_rcv : packet_rcv; 3871 skb_queue_purge(rb_queue); 3872 if (atomic_read(&po->mapped)) 3873 pr_err("packet_mmap: vma is busy: %d\n", 3874 atomic_read(&po->mapped)); 3875 } 3876 mutex_unlock(&po->pg_vec_lock); 3877 3878 spin_lock(&po->bind_lock); 3879 if (was_running) { 3880 po->num = num; 3881 register_prot_hook(sk); 3882 } 3883 spin_unlock(&po->bind_lock); 3884 if (closing && (po->tp_version > TPACKET_V2)) { 3885 /* Because we don't support block-based V3 on tx-ring */ 3886 if (!tx_ring) 3887 prb_shutdown_retire_blk_timer(po, tx_ring, rb_queue); 3888 } 3889 release_sock(sk); 3890 3891 if (pg_vec) 3892 free_pg_vec(pg_vec, order, req->tp_block_nr); 3893 out: 3894 return err; 3895 } 3896 3897 static int packet_mmap(struct file *file, struct socket *sock, 3898 struct vm_area_struct *vma) 3899 { 3900 struct sock *sk = sock->sk; 3901 struct packet_sock *po = pkt_sk(sk); 3902 unsigned long size, expected_size; 3903 struct packet_ring_buffer *rb; 3904 unsigned long start; 3905 int err = -EINVAL; 3906 int i; 3907 3908 if (vma->vm_pgoff) 3909 return -EINVAL; 3910 3911 mutex_lock(&po->pg_vec_lock); 3912 3913 expected_size = 0; 3914 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) { 3915 if (rb->pg_vec) { 3916 expected_size += rb->pg_vec_len 3917 * rb->pg_vec_pages 3918 * PAGE_SIZE; 3919 } 3920 } 3921 3922 if (expected_size == 0) 3923 goto out; 3924 3925 size = vma->vm_end - vma->vm_start; 3926 if (size != expected_size) 3927 goto out; 3928 3929 start = vma->vm_start; 3930 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) { 3931 if (rb->pg_vec == NULL) 3932 continue; 3933 3934 for (i = 0; i < rb->pg_vec_len; i++) { 3935 struct page *page; 3936 void *kaddr = rb->pg_vec[i].buffer; 3937 int pg_num; 3938 3939 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) { 3940 page = pgv_to_page(kaddr); 3941 err = vm_insert_page(vma, start, page); 3942 if (unlikely(err)) 3943 goto out; 3944 start += PAGE_SIZE; 3945 kaddr += PAGE_SIZE; 3946 } 3947 } 3948 } 3949 3950 atomic_inc(&po->mapped); 3951 vma->vm_ops = &packet_mmap_ops; 3952 err = 0; 3953 3954 out: 3955 mutex_unlock(&po->pg_vec_lock); 3956 return err; 3957 } 3958 3959 static const struct proto_ops packet_ops_spkt = { 3960 .family = PF_PACKET, 3961 .owner = THIS_MODULE, 3962 .release = packet_release, 3963 .bind = packet_bind_spkt, 3964 .connect = sock_no_connect, 3965 .socketpair = sock_no_socketpair, 3966 .accept = sock_no_accept, 3967 .getname = packet_getname_spkt, 3968 .poll = datagram_poll, 3969 .ioctl = packet_ioctl, 3970 .listen = sock_no_listen, 3971 .shutdown = sock_no_shutdown, 3972 .setsockopt = sock_no_setsockopt, 3973 .getsockopt = sock_no_getsockopt, 3974 .sendmsg = packet_sendmsg_spkt, 3975 .recvmsg = packet_recvmsg, 3976 .mmap = sock_no_mmap, 3977 .sendpage = sock_no_sendpage, 3978 }; 3979 3980 static const struct proto_ops packet_ops = { 3981 .family = PF_PACKET, 3982 .owner = THIS_MODULE, 3983 .release = packet_release, 3984 .bind = packet_bind, 3985 .connect = sock_no_connect, 3986 .socketpair = sock_no_socketpair, 3987 .accept = sock_no_accept, 3988 .getname = packet_getname, 3989 .poll = packet_poll, 3990 .ioctl = packet_ioctl, 3991 .listen = sock_no_listen, 3992 .shutdown = sock_no_shutdown, 3993 .setsockopt = packet_setsockopt, 3994 .getsockopt = packet_getsockopt, 3995 .sendmsg = packet_sendmsg, 3996 .recvmsg = packet_recvmsg, 3997 .mmap = packet_mmap, 3998 .sendpage = sock_no_sendpage, 3999 }; 4000 4001 static const struct net_proto_family packet_family_ops = { 4002 .family = PF_PACKET, 4003 .create = packet_create, 4004 .owner = THIS_MODULE, 4005 }; 4006 4007 static struct notifier_block packet_netdev_notifier = { 4008 .notifier_call = packet_notifier, 4009 }; 4010 4011 #ifdef CONFIG_PROC_FS 4012 4013 static void *packet_seq_start(struct seq_file *seq, loff_t *pos) 4014 __acquires(RCU) 4015 { 4016 struct net *net = seq_file_net(seq); 4017 4018 rcu_read_lock(); 4019 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos); 4020 } 4021 4022 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos) 4023 { 4024 struct net *net = seq_file_net(seq); 4025 return seq_hlist_next_rcu(v, &net->packet.sklist, pos); 4026 } 4027 4028 static void packet_seq_stop(struct seq_file *seq, void *v) 4029 __releases(RCU) 4030 { 4031 rcu_read_unlock(); 4032 } 4033 4034 static int packet_seq_show(struct seq_file *seq, void *v) 4035 { 4036 if (v == SEQ_START_TOKEN) 4037 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n"); 4038 else { 4039 struct sock *s = sk_entry(v); 4040 const struct packet_sock *po = pkt_sk(s); 4041 4042 seq_printf(seq, 4043 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n", 4044 s, 4045 atomic_read(&s->sk_refcnt), 4046 s->sk_type, 4047 ntohs(po->num), 4048 po->ifindex, 4049 po->running, 4050 atomic_read(&s->sk_rmem_alloc), 4051 from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)), 4052 sock_i_ino(s)); 4053 } 4054 4055 return 0; 4056 } 4057 4058 static const struct seq_operations packet_seq_ops = { 4059 .start = packet_seq_start, 4060 .next = packet_seq_next, 4061 .stop = packet_seq_stop, 4062 .show = packet_seq_show, 4063 }; 4064 4065 static int packet_seq_open(struct inode *inode, struct file *file) 4066 { 4067 return seq_open_net(inode, file, &packet_seq_ops, 4068 sizeof(struct seq_net_private)); 4069 } 4070 4071 static const struct file_operations packet_seq_fops = { 4072 .owner = THIS_MODULE, 4073 .open = packet_seq_open, 4074 .read = seq_read, 4075 .llseek = seq_lseek, 4076 .release = seq_release_net, 4077 }; 4078 4079 #endif 4080 4081 static int __net_init packet_net_init(struct net *net) 4082 { 4083 mutex_init(&net->packet.sklist_lock); 4084 INIT_HLIST_HEAD(&net->packet.sklist); 4085 4086 if (!proc_create("packet", 0, net->proc_net, &packet_seq_fops)) 4087 return -ENOMEM; 4088 4089 return 0; 4090 } 4091 4092 static void __net_exit packet_net_exit(struct net *net) 4093 { 4094 remove_proc_entry("packet", net->proc_net); 4095 } 4096 4097 static struct pernet_operations packet_net_ops = { 4098 .init = packet_net_init, 4099 .exit = packet_net_exit, 4100 }; 4101 4102 4103 static void __exit packet_exit(void) 4104 { 4105 unregister_netdevice_notifier(&packet_netdev_notifier); 4106 unregister_pernet_subsys(&packet_net_ops); 4107 sock_unregister(PF_PACKET); 4108 proto_unregister(&packet_proto); 4109 } 4110 4111 static int __init packet_init(void) 4112 { 4113 int rc = proto_register(&packet_proto, 0); 4114 4115 if (rc != 0) 4116 goto out; 4117 4118 sock_register(&packet_family_ops); 4119 register_pernet_subsys(&packet_net_ops); 4120 register_netdevice_notifier(&packet_netdev_notifier); 4121 out: 4122 return rc; 4123 } 4124 4125 module_init(packet_init); 4126 module_exit(packet_exit); 4127 MODULE_LICENSE("GPL"); 4128 MODULE_ALIAS_NETPROTO(PF_PACKET); 4129