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 netdev_features_t features; 244 struct netdev_queue *txq; 245 int ret = NETDEV_TX_BUSY; 246 247 if (unlikely(!netif_running(dev) || 248 !netif_carrier_ok(dev))) 249 goto drop; 250 251 features = netif_skb_features(skb); 252 if (skb_needs_linearize(skb, features) && 253 __skb_linearize(skb)) 254 goto drop; 255 256 txq = skb_get_tx_queue(dev, skb); 257 258 local_bh_disable(); 259 260 HARD_TX_LOCK(dev, txq, smp_processor_id()); 261 if (!netif_xmit_frozen_or_drv_stopped(txq)) 262 ret = netdev_start_xmit(skb, dev, txq, false); 263 HARD_TX_UNLOCK(dev, txq); 264 265 local_bh_enable(); 266 267 if (!dev_xmit_complete(ret)) 268 kfree_skb(skb); 269 270 return ret; 271 drop: 272 atomic_long_inc(&dev->tx_dropped); 273 kfree_skb(skb); 274 return NET_XMIT_DROP; 275 } 276 277 static struct net_device *packet_cached_dev_get(struct packet_sock *po) 278 { 279 struct net_device *dev; 280 281 rcu_read_lock(); 282 dev = rcu_dereference(po->cached_dev); 283 if (likely(dev)) 284 dev_hold(dev); 285 rcu_read_unlock(); 286 287 return dev; 288 } 289 290 static void packet_cached_dev_assign(struct packet_sock *po, 291 struct net_device *dev) 292 { 293 rcu_assign_pointer(po->cached_dev, dev); 294 } 295 296 static void packet_cached_dev_reset(struct packet_sock *po) 297 { 298 RCU_INIT_POINTER(po->cached_dev, NULL); 299 } 300 301 static bool packet_use_direct_xmit(const struct packet_sock *po) 302 { 303 return po->xmit == packet_direct_xmit; 304 } 305 306 static u16 __packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb) 307 { 308 return (u16) raw_smp_processor_id() % dev->real_num_tx_queues; 309 } 310 311 static void packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb) 312 { 313 const struct net_device_ops *ops = dev->netdev_ops; 314 u16 queue_index; 315 316 if (ops->ndo_select_queue) { 317 queue_index = ops->ndo_select_queue(dev, skb, NULL, 318 __packet_pick_tx_queue); 319 queue_index = netdev_cap_txqueue(dev, queue_index); 320 } else { 321 queue_index = __packet_pick_tx_queue(dev, skb); 322 } 323 324 skb_set_queue_mapping(skb, queue_index); 325 } 326 327 /* register_prot_hook must be invoked with the po->bind_lock held, 328 * or from a context in which asynchronous accesses to the packet 329 * socket is not possible (packet_create()). 330 */ 331 static void register_prot_hook(struct sock *sk) 332 { 333 struct packet_sock *po = pkt_sk(sk); 334 335 if (!po->running) { 336 if (po->fanout) 337 __fanout_link(sk, po); 338 else 339 dev_add_pack(&po->prot_hook); 340 341 sock_hold(sk); 342 po->running = 1; 343 } 344 } 345 346 /* {,__}unregister_prot_hook() must be invoked with the po->bind_lock 347 * held. If the sync parameter is true, we will temporarily drop 348 * the po->bind_lock and do a synchronize_net to make sure no 349 * asynchronous packet processing paths still refer to the elements 350 * of po->prot_hook. If the sync parameter is false, it is the 351 * callers responsibility to take care of this. 352 */ 353 static void __unregister_prot_hook(struct sock *sk, bool sync) 354 { 355 struct packet_sock *po = pkt_sk(sk); 356 357 po->running = 0; 358 359 if (po->fanout) 360 __fanout_unlink(sk, po); 361 else 362 __dev_remove_pack(&po->prot_hook); 363 364 __sock_put(sk); 365 366 if (sync) { 367 spin_unlock(&po->bind_lock); 368 synchronize_net(); 369 spin_lock(&po->bind_lock); 370 } 371 } 372 373 static void unregister_prot_hook(struct sock *sk, bool sync) 374 { 375 struct packet_sock *po = pkt_sk(sk); 376 377 if (po->running) 378 __unregister_prot_hook(sk, sync); 379 } 380 381 static inline struct page * __pure pgv_to_page(void *addr) 382 { 383 if (is_vmalloc_addr(addr)) 384 return vmalloc_to_page(addr); 385 return virt_to_page(addr); 386 } 387 388 static void __packet_set_status(struct packet_sock *po, void *frame, int status) 389 { 390 union tpacket_uhdr h; 391 392 h.raw = frame; 393 switch (po->tp_version) { 394 case TPACKET_V1: 395 h.h1->tp_status = status; 396 flush_dcache_page(pgv_to_page(&h.h1->tp_status)); 397 break; 398 case TPACKET_V2: 399 h.h2->tp_status = status; 400 flush_dcache_page(pgv_to_page(&h.h2->tp_status)); 401 break; 402 case TPACKET_V3: 403 default: 404 WARN(1, "TPACKET version not supported.\n"); 405 BUG(); 406 } 407 408 smp_wmb(); 409 } 410 411 static int __packet_get_status(struct packet_sock *po, void *frame) 412 { 413 union tpacket_uhdr h; 414 415 smp_rmb(); 416 417 h.raw = frame; 418 switch (po->tp_version) { 419 case TPACKET_V1: 420 flush_dcache_page(pgv_to_page(&h.h1->tp_status)); 421 return h.h1->tp_status; 422 case TPACKET_V2: 423 flush_dcache_page(pgv_to_page(&h.h2->tp_status)); 424 return h.h2->tp_status; 425 case TPACKET_V3: 426 default: 427 WARN(1, "TPACKET version not supported.\n"); 428 BUG(); 429 return 0; 430 } 431 } 432 433 static __u32 tpacket_get_timestamp(struct sk_buff *skb, struct timespec *ts, 434 unsigned int flags) 435 { 436 struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb); 437 438 if (shhwtstamps && 439 (flags & SOF_TIMESTAMPING_RAW_HARDWARE) && 440 ktime_to_timespec_cond(shhwtstamps->hwtstamp, ts)) 441 return TP_STATUS_TS_RAW_HARDWARE; 442 443 if (ktime_to_timespec_cond(skb->tstamp, ts)) 444 return TP_STATUS_TS_SOFTWARE; 445 446 return 0; 447 } 448 449 static __u32 __packet_set_timestamp(struct packet_sock *po, void *frame, 450 struct sk_buff *skb) 451 { 452 union tpacket_uhdr h; 453 struct timespec ts; 454 __u32 ts_status; 455 456 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp))) 457 return 0; 458 459 h.raw = frame; 460 switch (po->tp_version) { 461 case TPACKET_V1: 462 h.h1->tp_sec = ts.tv_sec; 463 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC; 464 break; 465 case TPACKET_V2: 466 h.h2->tp_sec = ts.tv_sec; 467 h.h2->tp_nsec = ts.tv_nsec; 468 break; 469 case TPACKET_V3: 470 default: 471 WARN(1, "TPACKET version not supported.\n"); 472 BUG(); 473 } 474 475 /* one flush is safe, as both fields always lie on the same cacheline */ 476 flush_dcache_page(pgv_to_page(&h.h1->tp_sec)); 477 smp_wmb(); 478 479 return ts_status; 480 } 481 482 static void *packet_lookup_frame(struct packet_sock *po, 483 struct packet_ring_buffer *rb, 484 unsigned int position, 485 int status) 486 { 487 unsigned int pg_vec_pos, frame_offset; 488 union tpacket_uhdr h; 489 490 pg_vec_pos = position / rb->frames_per_block; 491 frame_offset = position % rb->frames_per_block; 492 493 h.raw = rb->pg_vec[pg_vec_pos].buffer + 494 (frame_offset * rb->frame_size); 495 496 if (status != __packet_get_status(po, h.raw)) 497 return NULL; 498 499 return h.raw; 500 } 501 502 static void *packet_current_frame(struct packet_sock *po, 503 struct packet_ring_buffer *rb, 504 int status) 505 { 506 return packet_lookup_frame(po, rb, rb->head, status); 507 } 508 509 static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc) 510 { 511 del_timer_sync(&pkc->retire_blk_timer); 512 } 513 514 static void prb_shutdown_retire_blk_timer(struct packet_sock *po, 515 int tx_ring, 516 struct sk_buff_head *rb_queue) 517 { 518 struct tpacket_kbdq_core *pkc; 519 520 pkc = tx_ring ? GET_PBDQC_FROM_RB(&po->tx_ring) : 521 GET_PBDQC_FROM_RB(&po->rx_ring); 522 523 spin_lock_bh(&rb_queue->lock); 524 pkc->delete_blk_timer = 1; 525 spin_unlock_bh(&rb_queue->lock); 526 527 prb_del_retire_blk_timer(pkc); 528 } 529 530 static void prb_init_blk_timer(struct packet_sock *po, 531 struct tpacket_kbdq_core *pkc, 532 void (*func) (unsigned long)) 533 { 534 init_timer(&pkc->retire_blk_timer); 535 pkc->retire_blk_timer.data = (long)po; 536 pkc->retire_blk_timer.function = func; 537 pkc->retire_blk_timer.expires = jiffies; 538 } 539 540 static void prb_setup_retire_blk_timer(struct packet_sock *po, int tx_ring) 541 { 542 struct tpacket_kbdq_core *pkc; 543 544 if (tx_ring) 545 BUG(); 546 547 pkc = tx_ring ? GET_PBDQC_FROM_RB(&po->tx_ring) : 548 GET_PBDQC_FROM_RB(&po->rx_ring); 549 prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired); 550 } 551 552 static int prb_calc_retire_blk_tmo(struct packet_sock *po, 553 int blk_size_in_bytes) 554 { 555 struct net_device *dev; 556 unsigned int mbits = 0, msec = 0, div = 0, tmo = 0; 557 struct ethtool_cmd ecmd; 558 int err; 559 u32 speed; 560 561 rtnl_lock(); 562 dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex); 563 if (unlikely(!dev)) { 564 rtnl_unlock(); 565 return DEFAULT_PRB_RETIRE_TOV; 566 } 567 err = __ethtool_get_settings(dev, &ecmd); 568 speed = ethtool_cmd_speed(&ecmd); 569 rtnl_unlock(); 570 if (!err) { 571 /* 572 * If the link speed is so slow you don't really 573 * need to worry about perf anyways 574 */ 575 if (speed < SPEED_1000 || speed == SPEED_UNKNOWN) { 576 return DEFAULT_PRB_RETIRE_TOV; 577 } else { 578 msec = 1; 579 div = speed / 1000; 580 } 581 } 582 583 mbits = (blk_size_in_bytes * 8) / (1024 * 1024); 584 585 if (div) 586 mbits /= div; 587 588 tmo = mbits * msec; 589 590 if (div) 591 return tmo+1; 592 return tmo; 593 } 594 595 static void prb_init_ft_ops(struct tpacket_kbdq_core *p1, 596 union tpacket_req_u *req_u) 597 { 598 p1->feature_req_word = req_u->req3.tp_feature_req_word; 599 } 600 601 static void init_prb_bdqc(struct packet_sock *po, 602 struct packet_ring_buffer *rb, 603 struct pgv *pg_vec, 604 union tpacket_req_u *req_u, int tx_ring) 605 { 606 struct tpacket_kbdq_core *p1 = GET_PBDQC_FROM_RB(rb); 607 struct tpacket_block_desc *pbd; 608 609 memset(p1, 0x0, sizeof(*p1)); 610 611 p1->knxt_seq_num = 1; 612 p1->pkbdq = pg_vec; 613 pbd = (struct tpacket_block_desc *)pg_vec[0].buffer; 614 p1->pkblk_start = pg_vec[0].buffer; 615 p1->kblk_size = req_u->req3.tp_block_size; 616 p1->knum_blocks = req_u->req3.tp_block_nr; 617 p1->hdrlen = po->tp_hdrlen; 618 p1->version = po->tp_version; 619 p1->last_kactive_blk_num = 0; 620 po->stats.stats3.tp_freeze_q_cnt = 0; 621 if (req_u->req3.tp_retire_blk_tov) 622 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov; 623 else 624 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po, 625 req_u->req3.tp_block_size); 626 p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov); 627 p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv; 628 629 p1->max_frame_len = p1->kblk_size - BLK_PLUS_PRIV(p1->blk_sizeof_priv); 630 prb_init_ft_ops(p1, req_u); 631 prb_setup_retire_blk_timer(po, tx_ring); 632 prb_open_block(p1, pbd); 633 } 634 635 /* Do NOT update the last_blk_num first. 636 * Assumes sk_buff_head lock is held. 637 */ 638 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc) 639 { 640 mod_timer(&pkc->retire_blk_timer, 641 jiffies + pkc->tov_in_jiffies); 642 pkc->last_kactive_blk_num = pkc->kactive_blk_num; 643 } 644 645 /* 646 * Timer logic: 647 * 1) We refresh the timer only when we open a block. 648 * By doing this we don't waste cycles refreshing the timer 649 * on packet-by-packet basis. 650 * 651 * With a 1MB block-size, on a 1Gbps line, it will take 652 * i) ~8 ms to fill a block + ii) memcpy etc. 653 * In this cut we are not accounting for the memcpy time. 654 * 655 * So, if the user sets the 'tmo' to 10ms then the timer 656 * will never fire while the block is still getting filled 657 * (which is what we want). However, the user could choose 658 * to close a block early and that's fine. 659 * 660 * But when the timer does fire, we check whether or not to refresh it. 661 * Since the tmo granularity is in msecs, it is not too expensive 662 * to refresh the timer, lets say every '8' msecs. 663 * Either the user can set the 'tmo' or we can derive it based on 664 * a) line-speed and b) block-size. 665 * prb_calc_retire_blk_tmo() calculates the tmo. 666 * 667 */ 668 static void prb_retire_rx_blk_timer_expired(unsigned long data) 669 { 670 struct packet_sock *po = (struct packet_sock *)data; 671 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(&po->rx_ring); 672 unsigned int frozen; 673 struct tpacket_block_desc *pbd; 674 675 spin_lock(&po->sk.sk_receive_queue.lock); 676 677 frozen = prb_queue_frozen(pkc); 678 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc); 679 680 if (unlikely(pkc->delete_blk_timer)) 681 goto out; 682 683 /* We only need to plug the race when the block is partially filled. 684 * tpacket_rcv: 685 * lock(); increment BLOCK_NUM_PKTS; unlock() 686 * copy_bits() is in progress ... 687 * timer fires on other cpu: 688 * we can't retire the current block because copy_bits 689 * is in progress. 690 * 691 */ 692 if (BLOCK_NUM_PKTS(pbd)) { 693 while (atomic_read(&pkc->blk_fill_in_prog)) { 694 /* Waiting for skb_copy_bits to finish... */ 695 cpu_relax(); 696 } 697 } 698 699 if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) { 700 if (!frozen) { 701 if (!BLOCK_NUM_PKTS(pbd)) { 702 /* An empty block. Just refresh the timer. */ 703 goto refresh_timer; 704 } 705 prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO); 706 if (!prb_dispatch_next_block(pkc, po)) 707 goto refresh_timer; 708 else 709 goto out; 710 } else { 711 /* Case 1. Queue was frozen because user-space was 712 * lagging behind. 713 */ 714 if (prb_curr_blk_in_use(pkc, pbd)) { 715 /* 716 * Ok, user-space is still behind. 717 * So just refresh the timer. 718 */ 719 goto refresh_timer; 720 } else { 721 /* Case 2. queue was frozen,user-space caught up, 722 * now the link went idle && the timer fired. 723 * We don't have a block to close.So we open this 724 * block and restart the timer. 725 * opening a block thaws the queue,restarts timer 726 * Thawing/timer-refresh is a side effect. 727 */ 728 prb_open_block(pkc, pbd); 729 goto out; 730 } 731 } 732 } 733 734 refresh_timer: 735 _prb_refresh_rx_retire_blk_timer(pkc); 736 737 out: 738 spin_unlock(&po->sk.sk_receive_queue.lock); 739 } 740 741 static void prb_flush_block(struct tpacket_kbdq_core *pkc1, 742 struct tpacket_block_desc *pbd1, __u32 status) 743 { 744 /* Flush everything minus the block header */ 745 746 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1 747 u8 *start, *end; 748 749 start = (u8 *)pbd1; 750 751 /* Skip the block header(we know header WILL fit in 4K) */ 752 start += PAGE_SIZE; 753 754 end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end); 755 for (; start < end; start += PAGE_SIZE) 756 flush_dcache_page(pgv_to_page(start)); 757 758 smp_wmb(); 759 #endif 760 761 /* Now update the block status. */ 762 763 BLOCK_STATUS(pbd1) = status; 764 765 /* Flush the block header */ 766 767 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1 768 start = (u8 *)pbd1; 769 flush_dcache_page(pgv_to_page(start)); 770 771 smp_wmb(); 772 #endif 773 } 774 775 /* 776 * Side effect: 777 * 778 * 1) flush the block 779 * 2) Increment active_blk_num 780 * 781 * Note:We DONT refresh the timer on purpose. 782 * Because almost always the next block will be opened. 783 */ 784 static void prb_close_block(struct tpacket_kbdq_core *pkc1, 785 struct tpacket_block_desc *pbd1, 786 struct packet_sock *po, unsigned int stat) 787 { 788 __u32 status = TP_STATUS_USER | stat; 789 790 struct tpacket3_hdr *last_pkt; 791 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1; 792 struct sock *sk = &po->sk; 793 794 if (po->stats.stats3.tp_drops) 795 status |= TP_STATUS_LOSING; 796 797 last_pkt = (struct tpacket3_hdr *)pkc1->prev; 798 last_pkt->tp_next_offset = 0; 799 800 /* Get the ts of the last pkt */ 801 if (BLOCK_NUM_PKTS(pbd1)) { 802 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec; 803 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec; 804 } else { 805 /* Ok, we tmo'd - so get the current time. 806 * 807 * It shouldn't really happen as we don't close empty 808 * blocks. See prb_retire_rx_blk_timer_expired(). 809 */ 810 struct timespec ts; 811 getnstimeofday(&ts); 812 h1->ts_last_pkt.ts_sec = ts.tv_sec; 813 h1->ts_last_pkt.ts_nsec = ts.tv_nsec; 814 } 815 816 smp_wmb(); 817 818 /* Flush the block */ 819 prb_flush_block(pkc1, pbd1, status); 820 821 sk->sk_data_ready(sk); 822 823 pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1); 824 } 825 826 static void prb_thaw_queue(struct tpacket_kbdq_core *pkc) 827 { 828 pkc->reset_pending_on_curr_blk = 0; 829 } 830 831 /* 832 * Side effect of opening a block: 833 * 834 * 1) prb_queue is thawed. 835 * 2) retire_blk_timer is refreshed. 836 * 837 */ 838 static void prb_open_block(struct tpacket_kbdq_core *pkc1, 839 struct tpacket_block_desc *pbd1) 840 { 841 struct timespec ts; 842 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1; 843 844 smp_rmb(); 845 846 /* We could have just memset this but we will lose the 847 * flexibility of making the priv area sticky 848 */ 849 850 BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++; 851 BLOCK_NUM_PKTS(pbd1) = 0; 852 BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv); 853 854 getnstimeofday(&ts); 855 856 h1->ts_first_pkt.ts_sec = ts.tv_sec; 857 h1->ts_first_pkt.ts_nsec = ts.tv_nsec; 858 859 pkc1->pkblk_start = (char *)pbd1; 860 pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv); 861 862 BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv); 863 BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN; 864 865 pbd1->version = pkc1->version; 866 pkc1->prev = pkc1->nxt_offset; 867 pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size; 868 869 prb_thaw_queue(pkc1); 870 _prb_refresh_rx_retire_blk_timer(pkc1); 871 872 smp_wmb(); 873 } 874 875 /* 876 * Queue freeze logic: 877 * 1) Assume tp_block_nr = 8 blocks. 878 * 2) At time 't0', user opens Rx ring. 879 * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7 880 * 4) user-space is either sleeping or processing block '0'. 881 * 5) tpacket_rcv is currently filling block '7', since there is no space left, 882 * it will close block-7,loop around and try to fill block '0'. 883 * call-flow: 884 * __packet_lookup_frame_in_block 885 * prb_retire_current_block() 886 * prb_dispatch_next_block() 887 * |->(BLOCK_STATUS == USER) evaluates to true 888 * 5.1) Since block-0 is currently in-use, we just freeze the queue. 889 * 6) Now there are two cases: 890 * 6.1) Link goes idle right after the queue is frozen. 891 * But remember, the last open_block() refreshed the timer. 892 * When this timer expires,it will refresh itself so that we can 893 * re-open block-0 in near future. 894 * 6.2) Link is busy and keeps on receiving packets. This is a simple 895 * case and __packet_lookup_frame_in_block will check if block-0 896 * is free and can now be re-used. 897 */ 898 static void prb_freeze_queue(struct tpacket_kbdq_core *pkc, 899 struct packet_sock *po) 900 { 901 pkc->reset_pending_on_curr_blk = 1; 902 po->stats.stats3.tp_freeze_q_cnt++; 903 } 904 905 #define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT)) 906 907 /* 908 * If the next block is free then we will dispatch it 909 * and return a good offset. 910 * Else, we will freeze the queue. 911 * So, caller must check the return value. 912 */ 913 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc, 914 struct packet_sock *po) 915 { 916 struct tpacket_block_desc *pbd; 917 918 smp_rmb(); 919 920 /* 1. Get current block num */ 921 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc); 922 923 /* 2. If this block is currently in_use then freeze the queue */ 924 if (TP_STATUS_USER & BLOCK_STATUS(pbd)) { 925 prb_freeze_queue(pkc, po); 926 return NULL; 927 } 928 929 /* 930 * 3. 931 * open this block and return the offset where the first packet 932 * needs to get stored. 933 */ 934 prb_open_block(pkc, pbd); 935 return (void *)pkc->nxt_offset; 936 } 937 938 static void prb_retire_current_block(struct tpacket_kbdq_core *pkc, 939 struct packet_sock *po, unsigned int status) 940 { 941 struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc); 942 943 /* retire/close the current block */ 944 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) { 945 /* 946 * Plug the case where copy_bits() is in progress on 947 * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't 948 * have space to copy the pkt in the current block and 949 * called prb_retire_current_block() 950 * 951 * We don't need to worry about the TMO case because 952 * the timer-handler already handled this case. 953 */ 954 if (!(status & TP_STATUS_BLK_TMO)) { 955 while (atomic_read(&pkc->blk_fill_in_prog)) { 956 /* Waiting for skb_copy_bits to finish... */ 957 cpu_relax(); 958 } 959 } 960 prb_close_block(pkc, pbd, po, status); 961 return; 962 } 963 } 964 965 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc, 966 struct tpacket_block_desc *pbd) 967 { 968 return TP_STATUS_USER & BLOCK_STATUS(pbd); 969 } 970 971 static int prb_queue_frozen(struct tpacket_kbdq_core *pkc) 972 { 973 return pkc->reset_pending_on_curr_blk; 974 } 975 976 static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb) 977 { 978 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb); 979 atomic_dec(&pkc->blk_fill_in_prog); 980 } 981 982 static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc, 983 struct tpacket3_hdr *ppd) 984 { 985 ppd->hv1.tp_rxhash = skb_get_hash(pkc->skb); 986 } 987 988 static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc, 989 struct tpacket3_hdr *ppd) 990 { 991 ppd->hv1.tp_rxhash = 0; 992 } 993 994 static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc, 995 struct tpacket3_hdr *ppd) 996 { 997 if (skb_vlan_tag_present(pkc->skb)) { 998 ppd->hv1.tp_vlan_tci = skb_vlan_tag_get(pkc->skb); 999 ppd->hv1.tp_vlan_tpid = ntohs(pkc->skb->vlan_proto); 1000 ppd->tp_status = TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID; 1001 } else { 1002 ppd->hv1.tp_vlan_tci = 0; 1003 ppd->hv1.tp_vlan_tpid = 0; 1004 ppd->tp_status = TP_STATUS_AVAILABLE; 1005 } 1006 } 1007 1008 static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc, 1009 struct tpacket3_hdr *ppd) 1010 { 1011 ppd->hv1.tp_padding = 0; 1012 prb_fill_vlan_info(pkc, ppd); 1013 1014 if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH) 1015 prb_fill_rxhash(pkc, ppd); 1016 else 1017 prb_clear_rxhash(pkc, ppd); 1018 } 1019 1020 static void prb_fill_curr_block(char *curr, 1021 struct tpacket_kbdq_core *pkc, 1022 struct tpacket_block_desc *pbd, 1023 unsigned int len) 1024 { 1025 struct tpacket3_hdr *ppd; 1026 1027 ppd = (struct tpacket3_hdr *)curr; 1028 ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len); 1029 pkc->prev = curr; 1030 pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len); 1031 BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len); 1032 BLOCK_NUM_PKTS(pbd) += 1; 1033 atomic_inc(&pkc->blk_fill_in_prog); 1034 prb_run_all_ft_ops(pkc, ppd); 1035 } 1036 1037 /* Assumes caller has the sk->rx_queue.lock */ 1038 static void *__packet_lookup_frame_in_block(struct packet_sock *po, 1039 struct sk_buff *skb, 1040 int status, 1041 unsigned int len 1042 ) 1043 { 1044 struct tpacket_kbdq_core *pkc; 1045 struct tpacket_block_desc *pbd; 1046 char *curr, *end; 1047 1048 pkc = GET_PBDQC_FROM_RB(&po->rx_ring); 1049 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc); 1050 1051 /* Queue is frozen when user space is lagging behind */ 1052 if (prb_queue_frozen(pkc)) { 1053 /* 1054 * Check if that last block which caused the queue to freeze, 1055 * is still in_use by user-space. 1056 */ 1057 if (prb_curr_blk_in_use(pkc, pbd)) { 1058 /* Can't record this packet */ 1059 return NULL; 1060 } else { 1061 /* 1062 * Ok, the block was released by user-space. 1063 * Now let's open that block. 1064 * opening a block also thaws the queue. 1065 * Thawing is a side effect. 1066 */ 1067 prb_open_block(pkc, pbd); 1068 } 1069 } 1070 1071 smp_mb(); 1072 curr = pkc->nxt_offset; 1073 pkc->skb = skb; 1074 end = (char *)pbd + pkc->kblk_size; 1075 1076 /* first try the current block */ 1077 if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) { 1078 prb_fill_curr_block(curr, pkc, pbd, len); 1079 return (void *)curr; 1080 } 1081 1082 /* Ok, close the current block */ 1083 prb_retire_current_block(pkc, po, 0); 1084 1085 /* Now, try to dispatch the next block */ 1086 curr = (char *)prb_dispatch_next_block(pkc, po); 1087 if (curr) { 1088 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc); 1089 prb_fill_curr_block(curr, pkc, pbd, len); 1090 return (void *)curr; 1091 } 1092 1093 /* 1094 * No free blocks are available.user_space hasn't caught up yet. 1095 * Queue was just frozen and now this packet will get dropped. 1096 */ 1097 return NULL; 1098 } 1099 1100 static void *packet_current_rx_frame(struct packet_sock *po, 1101 struct sk_buff *skb, 1102 int status, unsigned int len) 1103 { 1104 char *curr = NULL; 1105 switch (po->tp_version) { 1106 case TPACKET_V1: 1107 case TPACKET_V2: 1108 curr = packet_lookup_frame(po, &po->rx_ring, 1109 po->rx_ring.head, status); 1110 return curr; 1111 case TPACKET_V3: 1112 return __packet_lookup_frame_in_block(po, skb, status, len); 1113 default: 1114 WARN(1, "TPACKET version not supported\n"); 1115 BUG(); 1116 return NULL; 1117 } 1118 } 1119 1120 static void *prb_lookup_block(struct packet_sock *po, 1121 struct packet_ring_buffer *rb, 1122 unsigned int idx, 1123 int status) 1124 { 1125 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb); 1126 struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, idx); 1127 1128 if (status != BLOCK_STATUS(pbd)) 1129 return NULL; 1130 return pbd; 1131 } 1132 1133 static int prb_previous_blk_num(struct packet_ring_buffer *rb) 1134 { 1135 unsigned int prev; 1136 if (rb->prb_bdqc.kactive_blk_num) 1137 prev = rb->prb_bdqc.kactive_blk_num-1; 1138 else 1139 prev = rb->prb_bdqc.knum_blocks-1; 1140 return prev; 1141 } 1142 1143 /* Assumes caller has held the rx_queue.lock */ 1144 static void *__prb_previous_block(struct packet_sock *po, 1145 struct packet_ring_buffer *rb, 1146 int status) 1147 { 1148 unsigned int previous = prb_previous_blk_num(rb); 1149 return prb_lookup_block(po, rb, previous, status); 1150 } 1151 1152 static void *packet_previous_rx_frame(struct packet_sock *po, 1153 struct packet_ring_buffer *rb, 1154 int status) 1155 { 1156 if (po->tp_version <= TPACKET_V2) 1157 return packet_previous_frame(po, rb, status); 1158 1159 return __prb_previous_block(po, rb, status); 1160 } 1161 1162 static void packet_increment_rx_head(struct packet_sock *po, 1163 struct packet_ring_buffer *rb) 1164 { 1165 switch (po->tp_version) { 1166 case TPACKET_V1: 1167 case TPACKET_V2: 1168 return packet_increment_head(rb); 1169 case TPACKET_V3: 1170 default: 1171 WARN(1, "TPACKET version not supported.\n"); 1172 BUG(); 1173 return; 1174 } 1175 } 1176 1177 static void *packet_previous_frame(struct packet_sock *po, 1178 struct packet_ring_buffer *rb, 1179 int status) 1180 { 1181 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max; 1182 return packet_lookup_frame(po, rb, previous, status); 1183 } 1184 1185 static void packet_increment_head(struct packet_ring_buffer *buff) 1186 { 1187 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0; 1188 } 1189 1190 static void packet_inc_pending(struct packet_ring_buffer *rb) 1191 { 1192 this_cpu_inc(*rb->pending_refcnt); 1193 } 1194 1195 static void packet_dec_pending(struct packet_ring_buffer *rb) 1196 { 1197 this_cpu_dec(*rb->pending_refcnt); 1198 } 1199 1200 static unsigned int packet_read_pending(const struct packet_ring_buffer *rb) 1201 { 1202 unsigned int refcnt = 0; 1203 int cpu; 1204 1205 /* We don't use pending refcount in rx_ring. */ 1206 if (rb->pending_refcnt == NULL) 1207 return 0; 1208 1209 for_each_possible_cpu(cpu) 1210 refcnt += *per_cpu_ptr(rb->pending_refcnt, cpu); 1211 1212 return refcnt; 1213 } 1214 1215 static int packet_alloc_pending(struct packet_sock *po) 1216 { 1217 po->rx_ring.pending_refcnt = NULL; 1218 1219 po->tx_ring.pending_refcnt = alloc_percpu(unsigned int); 1220 if (unlikely(po->tx_ring.pending_refcnt == NULL)) 1221 return -ENOBUFS; 1222 1223 return 0; 1224 } 1225 1226 static void packet_free_pending(struct packet_sock *po) 1227 { 1228 free_percpu(po->tx_ring.pending_refcnt); 1229 } 1230 1231 static bool packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb) 1232 { 1233 struct sock *sk = &po->sk; 1234 bool has_room; 1235 1236 if (po->prot_hook.func != tpacket_rcv) 1237 return (atomic_read(&sk->sk_rmem_alloc) + skb->truesize) 1238 <= sk->sk_rcvbuf; 1239 1240 spin_lock(&sk->sk_receive_queue.lock); 1241 if (po->tp_version == TPACKET_V3) 1242 has_room = prb_lookup_block(po, &po->rx_ring, 1243 po->rx_ring.prb_bdqc.kactive_blk_num, 1244 TP_STATUS_KERNEL); 1245 else 1246 has_room = packet_lookup_frame(po, &po->rx_ring, 1247 po->rx_ring.head, 1248 TP_STATUS_KERNEL); 1249 spin_unlock(&sk->sk_receive_queue.lock); 1250 1251 return has_room; 1252 } 1253 1254 static void packet_sock_destruct(struct sock *sk) 1255 { 1256 skb_queue_purge(&sk->sk_error_queue); 1257 1258 WARN_ON(atomic_read(&sk->sk_rmem_alloc)); 1259 WARN_ON(atomic_read(&sk->sk_wmem_alloc)); 1260 1261 if (!sock_flag(sk, SOCK_DEAD)) { 1262 pr_err("Attempt to release alive packet socket: %p\n", sk); 1263 return; 1264 } 1265 1266 sk_refcnt_debug_dec(sk); 1267 } 1268 1269 static int fanout_rr_next(struct packet_fanout *f, unsigned int num) 1270 { 1271 int x = atomic_read(&f->rr_cur) + 1; 1272 1273 if (x >= num) 1274 x = 0; 1275 1276 return x; 1277 } 1278 1279 static unsigned int fanout_demux_hash(struct packet_fanout *f, 1280 struct sk_buff *skb, 1281 unsigned int num) 1282 { 1283 return reciprocal_scale(skb_get_hash(skb), num); 1284 } 1285 1286 static unsigned int fanout_demux_lb(struct packet_fanout *f, 1287 struct sk_buff *skb, 1288 unsigned int num) 1289 { 1290 int cur, old; 1291 1292 cur = atomic_read(&f->rr_cur); 1293 while ((old = atomic_cmpxchg(&f->rr_cur, cur, 1294 fanout_rr_next(f, num))) != cur) 1295 cur = old; 1296 return cur; 1297 } 1298 1299 static unsigned int fanout_demux_cpu(struct packet_fanout *f, 1300 struct sk_buff *skb, 1301 unsigned int num) 1302 { 1303 return smp_processor_id() % num; 1304 } 1305 1306 static unsigned int fanout_demux_rnd(struct packet_fanout *f, 1307 struct sk_buff *skb, 1308 unsigned int num) 1309 { 1310 return prandom_u32_max(num); 1311 } 1312 1313 static unsigned int fanout_demux_rollover(struct packet_fanout *f, 1314 struct sk_buff *skb, 1315 unsigned int idx, unsigned int skip, 1316 unsigned int num) 1317 { 1318 unsigned int i, j; 1319 1320 i = j = min_t(int, f->next[idx], num - 1); 1321 do { 1322 if (i != skip && packet_rcv_has_room(pkt_sk(f->arr[i]), skb)) { 1323 if (i != j) 1324 f->next[idx] = i; 1325 return i; 1326 } 1327 if (++i == num) 1328 i = 0; 1329 } while (i != j); 1330 1331 return idx; 1332 } 1333 1334 static unsigned int fanout_demux_qm(struct packet_fanout *f, 1335 struct sk_buff *skb, 1336 unsigned int num) 1337 { 1338 return skb_get_queue_mapping(skb) % num; 1339 } 1340 1341 static bool fanout_has_flag(struct packet_fanout *f, u16 flag) 1342 { 1343 return f->flags & (flag >> 8); 1344 } 1345 1346 static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev, 1347 struct packet_type *pt, struct net_device *orig_dev) 1348 { 1349 struct packet_fanout *f = pt->af_packet_priv; 1350 unsigned int num = f->num_members; 1351 struct packet_sock *po; 1352 unsigned int idx; 1353 1354 if (!net_eq(dev_net(dev), read_pnet(&f->net)) || 1355 !num) { 1356 kfree_skb(skb); 1357 return 0; 1358 } 1359 1360 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_DEFRAG)) { 1361 skb = ip_check_defrag(skb, IP_DEFRAG_AF_PACKET); 1362 if (!skb) 1363 return 0; 1364 } 1365 switch (f->type) { 1366 case PACKET_FANOUT_HASH: 1367 default: 1368 idx = fanout_demux_hash(f, skb, num); 1369 break; 1370 case PACKET_FANOUT_LB: 1371 idx = fanout_demux_lb(f, skb, num); 1372 break; 1373 case PACKET_FANOUT_CPU: 1374 idx = fanout_demux_cpu(f, skb, num); 1375 break; 1376 case PACKET_FANOUT_RND: 1377 idx = fanout_demux_rnd(f, skb, num); 1378 break; 1379 case PACKET_FANOUT_QM: 1380 idx = fanout_demux_qm(f, skb, num); 1381 break; 1382 case PACKET_FANOUT_ROLLOVER: 1383 idx = fanout_demux_rollover(f, skb, 0, (unsigned int) -1, num); 1384 break; 1385 } 1386 1387 po = pkt_sk(f->arr[idx]); 1388 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER) && 1389 unlikely(!packet_rcv_has_room(po, skb))) { 1390 idx = fanout_demux_rollover(f, skb, idx, idx, num); 1391 po = pkt_sk(f->arr[idx]); 1392 } 1393 1394 return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev); 1395 } 1396 1397 DEFINE_MUTEX(fanout_mutex); 1398 EXPORT_SYMBOL_GPL(fanout_mutex); 1399 static LIST_HEAD(fanout_list); 1400 1401 static void __fanout_link(struct sock *sk, struct packet_sock *po) 1402 { 1403 struct packet_fanout *f = po->fanout; 1404 1405 spin_lock(&f->lock); 1406 f->arr[f->num_members] = sk; 1407 smp_wmb(); 1408 f->num_members++; 1409 spin_unlock(&f->lock); 1410 } 1411 1412 static void __fanout_unlink(struct sock *sk, struct packet_sock *po) 1413 { 1414 struct packet_fanout *f = po->fanout; 1415 int i; 1416 1417 spin_lock(&f->lock); 1418 for (i = 0; i < f->num_members; i++) { 1419 if (f->arr[i] == sk) 1420 break; 1421 } 1422 BUG_ON(i >= f->num_members); 1423 f->arr[i] = f->arr[f->num_members - 1]; 1424 f->num_members--; 1425 spin_unlock(&f->lock); 1426 } 1427 1428 static bool match_fanout_group(struct packet_type *ptype, struct sock *sk) 1429 { 1430 if (ptype->af_packet_priv == (void *)((struct packet_sock *)sk)->fanout) 1431 return true; 1432 1433 return false; 1434 } 1435 1436 static int fanout_add(struct sock *sk, u16 id, u16 type_flags) 1437 { 1438 struct packet_sock *po = pkt_sk(sk); 1439 struct packet_fanout *f, *match; 1440 u8 type = type_flags & 0xff; 1441 u8 flags = type_flags >> 8; 1442 int err; 1443 1444 switch (type) { 1445 case PACKET_FANOUT_ROLLOVER: 1446 if (type_flags & PACKET_FANOUT_FLAG_ROLLOVER) 1447 return -EINVAL; 1448 case PACKET_FANOUT_HASH: 1449 case PACKET_FANOUT_LB: 1450 case PACKET_FANOUT_CPU: 1451 case PACKET_FANOUT_RND: 1452 case PACKET_FANOUT_QM: 1453 break; 1454 default: 1455 return -EINVAL; 1456 } 1457 1458 if (!po->running) 1459 return -EINVAL; 1460 1461 if (po->fanout) 1462 return -EALREADY; 1463 1464 mutex_lock(&fanout_mutex); 1465 match = NULL; 1466 list_for_each_entry(f, &fanout_list, list) { 1467 if (f->id == id && 1468 read_pnet(&f->net) == sock_net(sk)) { 1469 match = f; 1470 break; 1471 } 1472 } 1473 err = -EINVAL; 1474 if (match && match->flags != flags) 1475 goto out; 1476 if (!match) { 1477 err = -ENOMEM; 1478 match = kzalloc(sizeof(*match), GFP_KERNEL); 1479 if (!match) 1480 goto out; 1481 write_pnet(&match->net, sock_net(sk)); 1482 match->id = id; 1483 match->type = type; 1484 match->flags = flags; 1485 atomic_set(&match->rr_cur, 0); 1486 INIT_LIST_HEAD(&match->list); 1487 spin_lock_init(&match->lock); 1488 atomic_set(&match->sk_ref, 0); 1489 match->prot_hook.type = po->prot_hook.type; 1490 match->prot_hook.dev = po->prot_hook.dev; 1491 match->prot_hook.func = packet_rcv_fanout; 1492 match->prot_hook.af_packet_priv = match; 1493 match->prot_hook.id_match = match_fanout_group; 1494 dev_add_pack(&match->prot_hook); 1495 list_add(&match->list, &fanout_list); 1496 } 1497 err = -EINVAL; 1498 if (match->type == type && 1499 match->prot_hook.type == po->prot_hook.type && 1500 match->prot_hook.dev == po->prot_hook.dev) { 1501 err = -ENOSPC; 1502 if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) { 1503 __dev_remove_pack(&po->prot_hook); 1504 po->fanout = match; 1505 atomic_inc(&match->sk_ref); 1506 __fanout_link(sk, po); 1507 err = 0; 1508 } 1509 } 1510 out: 1511 mutex_unlock(&fanout_mutex); 1512 return err; 1513 } 1514 1515 static void fanout_release(struct sock *sk) 1516 { 1517 struct packet_sock *po = pkt_sk(sk); 1518 struct packet_fanout *f; 1519 1520 f = po->fanout; 1521 if (!f) 1522 return; 1523 1524 mutex_lock(&fanout_mutex); 1525 po->fanout = NULL; 1526 1527 if (atomic_dec_and_test(&f->sk_ref)) { 1528 list_del(&f->list); 1529 dev_remove_pack(&f->prot_hook); 1530 kfree(f); 1531 } 1532 mutex_unlock(&fanout_mutex); 1533 } 1534 1535 static const struct proto_ops packet_ops; 1536 1537 static const struct proto_ops packet_ops_spkt; 1538 1539 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev, 1540 struct packet_type *pt, struct net_device *orig_dev) 1541 { 1542 struct sock *sk; 1543 struct sockaddr_pkt *spkt; 1544 1545 /* 1546 * When we registered the protocol we saved the socket in the data 1547 * field for just this event. 1548 */ 1549 1550 sk = pt->af_packet_priv; 1551 1552 /* 1553 * Yank back the headers [hope the device set this 1554 * right or kerboom...] 1555 * 1556 * Incoming packets have ll header pulled, 1557 * push it back. 1558 * 1559 * For outgoing ones skb->data == skb_mac_header(skb) 1560 * so that this procedure is noop. 1561 */ 1562 1563 if (skb->pkt_type == PACKET_LOOPBACK) 1564 goto out; 1565 1566 if (!net_eq(dev_net(dev), sock_net(sk))) 1567 goto out; 1568 1569 skb = skb_share_check(skb, GFP_ATOMIC); 1570 if (skb == NULL) 1571 goto oom; 1572 1573 /* drop any routing info */ 1574 skb_dst_drop(skb); 1575 1576 /* drop conntrack reference */ 1577 nf_reset(skb); 1578 1579 spkt = &PACKET_SKB_CB(skb)->sa.pkt; 1580 1581 skb_push(skb, skb->data - skb_mac_header(skb)); 1582 1583 /* 1584 * The SOCK_PACKET socket receives _all_ frames. 1585 */ 1586 1587 spkt->spkt_family = dev->type; 1588 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device)); 1589 spkt->spkt_protocol = skb->protocol; 1590 1591 /* 1592 * Charge the memory to the socket. This is done specifically 1593 * to prevent sockets using all the memory up. 1594 */ 1595 1596 if (sock_queue_rcv_skb(sk, skb) == 0) 1597 return 0; 1598 1599 out: 1600 kfree_skb(skb); 1601 oom: 1602 return 0; 1603 } 1604 1605 1606 /* 1607 * Output a raw packet to a device layer. This bypasses all the other 1608 * protocol layers and you must therefore supply it with a complete frame 1609 */ 1610 1611 static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock, 1612 struct msghdr *msg, size_t len) 1613 { 1614 struct sock *sk = sock->sk; 1615 DECLARE_SOCKADDR(struct sockaddr_pkt *, saddr, msg->msg_name); 1616 struct sk_buff *skb = NULL; 1617 struct net_device *dev; 1618 __be16 proto = 0; 1619 int err; 1620 int extra_len = 0; 1621 1622 /* 1623 * Get and verify the address. 1624 */ 1625 1626 if (saddr) { 1627 if (msg->msg_namelen < sizeof(struct sockaddr)) 1628 return -EINVAL; 1629 if (msg->msg_namelen == sizeof(struct sockaddr_pkt)) 1630 proto = saddr->spkt_protocol; 1631 } else 1632 return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */ 1633 1634 /* 1635 * Find the device first to size check it 1636 */ 1637 1638 saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0; 1639 retry: 1640 rcu_read_lock(); 1641 dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device); 1642 err = -ENODEV; 1643 if (dev == NULL) 1644 goto out_unlock; 1645 1646 err = -ENETDOWN; 1647 if (!(dev->flags & IFF_UP)) 1648 goto out_unlock; 1649 1650 /* 1651 * You may not queue a frame bigger than the mtu. This is the lowest level 1652 * raw protocol and you must do your own fragmentation at this level. 1653 */ 1654 1655 if (unlikely(sock_flag(sk, SOCK_NOFCS))) { 1656 if (!netif_supports_nofcs(dev)) { 1657 err = -EPROTONOSUPPORT; 1658 goto out_unlock; 1659 } 1660 extra_len = 4; /* We're doing our own CRC */ 1661 } 1662 1663 err = -EMSGSIZE; 1664 if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len) 1665 goto out_unlock; 1666 1667 if (!skb) { 1668 size_t reserved = LL_RESERVED_SPACE(dev); 1669 int tlen = dev->needed_tailroom; 1670 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0; 1671 1672 rcu_read_unlock(); 1673 skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL); 1674 if (skb == NULL) 1675 return -ENOBUFS; 1676 /* FIXME: Save some space for broken drivers that write a hard 1677 * header at transmission time by themselves. PPP is the notable 1678 * one here. This should really be fixed at the driver level. 1679 */ 1680 skb_reserve(skb, reserved); 1681 skb_reset_network_header(skb); 1682 1683 /* Try to align data part correctly */ 1684 if (hhlen) { 1685 skb->data -= hhlen; 1686 skb->tail -= hhlen; 1687 if (len < hhlen) 1688 skb_reset_network_header(skb); 1689 } 1690 err = memcpy_from_msg(skb_put(skb, len), msg, len); 1691 if (err) 1692 goto out_free; 1693 goto retry; 1694 } 1695 1696 if (len > (dev->mtu + dev->hard_header_len + extra_len)) { 1697 /* Earlier code assumed this would be a VLAN pkt, 1698 * double-check this now that we have the actual 1699 * packet in hand. 1700 */ 1701 struct ethhdr *ehdr; 1702 skb_reset_mac_header(skb); 1703 ehdr = eth_hdr(skb); 1704 if (ehdr->h_proto != htons(ETH_P_8021Q)) { 1705 err = -EMSGSIZE; 1706 goto out_unlock; 1707 } 1708 } 1709 1710 skb->protocol = proto; 1711 skb->dev = dev; 1712 skb->priority = sk->sk_priority; 1713 skb->mark = sk->sk_mark; 1714 1715 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags); 1716 1717 if (unlikely(extra_len == 4)) 1718 skb->no_fcs = 1; 1719 1720 skb_probe_transport_header(skb, 0); 1721 1722 dev_queue_xmit(skb); 1723 rcu_read_unlock(); 1724 return len; 1725 1726 out_unlock: 1727 rcu_read_unlock(); 1728 out_free: 1729 kfree_skb(skb); 1730 return err; 1731 } 1732 1733 static unsigned int run_filter(const struct sk_buff *skb, 1734 const struct sock *sk, 1735 unsigned int res) 1736 { 1737 struct sk_filter *filter; 1738 1739 rcu_read_lock(); 1740 filter = rcu_dereference(sk->sk_filter); 1741 if (filter != NULL) 1742 res = SK_RUN_FILTER(filter, skb); 1743 rcu_read_unlock(); 1744 1745 return res; 1746 } 1747 1748 /* 1749 * This function makes lazy skb cloning in hope that most of packets 1750 * are discarded by BPF. 1751 * 1752 * Note tricky part: we DO mangle shared skb! skb->data, skb->len 1753 * and skb->cb are mangled. It works because (and until) packets 1754 * falling here are owned by current CPU. Output packets are cloned 1755 * by dev_queue_xmit_nit(), input packets are processed by net_bh 1756 * sequencially, so that if we return skb to original state on exit, 1757 * we will not harm anyone. 1758 */ 1759 1760 static int packet_rcv(struct sk_buff *skb, struct net_device *dev, 1761 struct packet_type *pt, struct net_device *orig_dev) 1762 { 1763 struct sock *sk; 1764 struct sockaddr_ll *sll; 1765 struct packet_sock *po; 1766 u8 *skb_head = skb->data; 1767 int skb_len = skb->len; 1768 unsigned int snaplen, res; 1769 1770 if (skb->pkt_type == PACKET_LOOPBACK) 1771 goto drop; 1772 1773 sk = pt->af_packet_priv; 1774 po = pkt_sk(sk); 1775 1776 if (!net_eq(dev_net(dev), sock_net(sk))) 1777 goto drop; 1778 1779 skb->dev = dev; 1780 1781 if (dev->header_ops) { 1782 /* The device has an explicit notion of ll header, 1783 * exported to higher levels. 1784 * 1785 * Otherwise, the device hides details of its frame 1786 * structure, so that corresponding packet head is 1787 * never delivered to user. 1788 */ 1789 if (sk->sk_type != SOCK_DGRAM) 1790 skb_push(skb, skb->data - skb_mac_header(skb)); 1791 else if (skb->pkt_type == PACKET_OUTGOING) { 1792 /* Special case: outgoing packets have ll header at head */ 1793 skb_pull(skb, skb_network_offset(skb)); 1794 } 1795 } 1796 1797 snaplen = skb->len; 1798 1799 res = run_filter(skb, sk, snaplen); 1800 if (!res) 1801 goto drop_n_restore; 1802 if (snaplen > res) 1803 snaplen = res; 1804 1805 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) 1806 goto drop_n_acct; 1807 1808 if (skb_shared(skb)) { 1809 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC); 1810 if (nskb == NULL) 1811 goto drop_n_acct; 1812 1813 if (skb_head != skb->data) { 1814 skb->data = skb_head; 1815 skb->len = skb_len; 1816 } 1817 consume_skb(skb); 1818 skb = nskb; 1819 } 1820 1821 BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 > 1822 sizeof(skb->cb)); 1823 1824 sll = &PACKET_SKB_CB(skb)->sa.ll; 1825 sll->sll_family = AF_PACKET; 1826 sll->sll_hatype = dev->type; 1827 sll->sll_protocol = skb->protocol; 1828 sll->sll_pkttype = skb->pkt_type; 1829 if (unlikely(po->origdev)) 1830 sll->sll_ifindex = orig_dev->ifindex; 1831 else 1832 sll->sll_ifindex = dev->ifindex; 1833 1834 sll->sll_halen = dev_parse_header(skb, sll->sll_addr); 1835 1836 PACKET_SKB_CB(skb)->origlen = skb->len; 1837 1838 if (pskb_trim(skb, snaplen)) 1839 goto drop_n_acct; 1840 1841 skb_set_owner_r(skb, sk); 1842 skb->dev = NULL; 1843 skb_dst_drop(skb); 1844 1845 /* drop conntrack reference */ 1846 nf_reset(skb); 1847 1848 spin_lock(&sk->sk_receive_queue.lock); 1849 po->stats.stats1.tp_packets++; 1850 skb->dropcount = atomic_read(&sk->sk_drops); 1851 __skb_queue_tail(&sk->sk_receive_queue, skb); 1852 spin_unlock(&sk->sk_receive_queue.lock); 1853 sk->sk_data_ready(sk); 1854 return 0; 1855 1856 drop_n_acct: 1857 spin_lock(&sk->sk_receive_queue.lock); 1858 po->stats.stats1.tp_drops++; 1859 atomic_inc(&sk->sk_drops); 1860 spin_unlock(&sk->sk_receive_queue.lock); 1861 1862 drop_n_restore: 1863 if (skb_head != skb->data && skb_shared(skb)) { 1864 skb->data = skb_head; 1865 skb->len = skb_len; 1866 } 1867 drop: 1868 consume_skb(skb); 1869 return 0; 1870 } 1871 1872 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, 1873 struct packet_type *pt, struct net_device *orig_dev) 1874 { 1875 struct sock *sk; 1876 struct packet_sock *po; 1877 struct sockaddr_ll *sll; 1878 union tpacket_uhdr h; 1879 u8 *skb_head = skb->data; 1880 int skb_len = skb->len; 1881 unsigned int snaplen, res; 1882 unsigned long status = TP_STATUS_USER; 1883 unsigned short macoff, netoff, hdrlen; 1884 struct sk_buff *copy_skb = NULL; 1885 struct timespec ts; 1886 __u32 ts_status; 1887 1888 /* struct tpacket{2,3}_hdr is aligned to a multiple of TPACKET_ALIGNMENT. 1889 * We may add members to them until current aligned size without forcing 1890 * userspace to call getsockopt(..., PACKET_HDRLEN, ...). 1891 */ 1892 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h2)) != 32); 1893 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h3)) != 48); 1894 1895 if (skb->pkt_type == PACKET_LOOPBACK) 1896 goto drop; 1897 1898 sk = pt->af_packet_priv; 1899 po = pkt_sk(sk); 1900 1901 if (!net_eq(dev_net(dev), sock_net(sk))) 1902 goto drop; 1903 1904 if (dev->header_ops) { 1905 if (sk->sk_type != SOCK_DGRAM) 1906 skb_push(skb, skb->data - skb_mac_header(skb)); 1907 else if (skb->pkt_type == PACKET_OUTGOING) { 1908 /* Special case: outgoing packets have ll header at head */ 1909 skb_pull(skb, skb_network_offset(skb)); 1910 } 1911 } 1912 1913 if (skb->ip_summed == CHECKSUM_PARTIAL) 1914 status |= TP_STATUS_CSUMNOTREADY; 1915 1916 snaplen = skb->len; 1917 1918 res = run_filter(skb, sk, snaplen); 1919 if (!res) 1920 goto drop_n_restore; 1921 if (snaplen > res) 1922 snaplen = res; 1923 1924 if (sk->sk_type == SOCK_DGRAM) { 1925 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 + 1926 po->tp_reserve; 1927 } else { 1928 unsigned int maclen = skb_network_offset(skb); 1929 netoff = TPACKET_ALIGN(po->tp_hdrlen + 1930 (maclen < 16 ? 16 : maclen)) + 1931 po->tp_reserve; 1932 macoff = netoff - maclen; 1933 } 1934 if (po->tp_version <= TPACKET_V2) { 1935 if (macoff + snaplen > po->rx_ring.frame_size) { 1936 if (po->copy_thresh && 1937 atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) { 1938 if (skb_shared(skb)) { 1939 copy_skb = skb_clone(skb, GFP_ATOMIC); 1940 } else { 1941 copy_skb = skb_get(skb); 1942 skb_head = skb->data; 1943 } 1944 if (copy_skb) 1945 skb_set_owner_r(copy_skb, sk); 1946 } 1947 snaplen = po->rx_ring.frame_size - macoff; 1948 if ((int)snaplen < 0) 1949 snaplen = 0; 1950 } 1951 } else if (unlikely(macoff + snaplen > 1952 GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len)) { 1953 u32 nval; 1954 1955 nval = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len - macoff; 1956 pr_err_once("tpacket_rcv: packet too big, clamped from %u to %u. macoff=%u\n", 1957 snaplen, nval, macoff); 1958 snaplen = nval; 1959 if (unlikely((int)snaplen < 0)) { 1960 snaplen = 0; 1961 macoff = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len; 1962 } 1963 } 1964 spin_lock(&sk->sk_receive_queue.lock); 1965 h.raw = packet_current_rx_frame(po, skb, 1966 TP_STATUS_KERNEL, (macoff+snaplen)); 1967 if (!h.raw) 1968 goto ring_is_full; 1969 if (po->tp_version <= TPACKET_V2) { 1970 packet_increment_rx_head(po, &po->rx_ring); 1971 /* 1972 * LOSING will be reported till you read the stats, 1973 * because it's COR - Clear On Read. 1974 * Anyways, moving it for V1/V2 only as V3 doesn't need this 1975 * at packet level. 1976 */ 1977 if (po->stats.stats1.tp_drops) 1978 status |= TP_STATUS_LOSING; 1979 } 1980 po->stats.stats1.tp_packets++; 1981 if (copy_skb) { 1982 status |= TP_STATUS_COPY; 1983 __skb_queue_tail(&sk->sk_receive_queue, copy_skb); 1984 } 1985 spin_unlock(&sk->sk_receive_queue.lock); 1986 1987 skb_copy_bits(skb, 0, h.raw + macoff, snaplen); 1988 1989 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp))) 1990 getnstimeofday(&ts); 1991 1992 status |= ts_status; 1993 1994 switch (po->tp_version) { 1995 case TPACKET_V1: 1996 h.h1->tp_len = skb->len; 1997 h.h1->tp_snaplen = snaplen; 1998 h.h1->tp_mac = macoff; 1999 h.h1->tp_net = netoff; 2000 h.h1->tp_sec = ts.tv_sec; 2001 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC; 2002 hdrlen = sizeof(*h.h1); 2003 break; 2004 case TPACKET_V2: 2005 h.h2->tp_len = skb->len; 2006 h.h2->tp_snaplen = snaplen; 2007 h.h2->tp_mac = macoff; 2008 h.h2->tp_net = netoff; 2009 h.h2->tp_sec = ts.tv_sec; 2010 h.h2->tp_nsec = ts.tv_nsec; 2011 if (skb_vlan_tag_present(skb)) { 2012 h.h2->tp_vlan_tci = skb_vlan_tag_get(skb); 2013 h.h2->tp_vlan_tpid = ntohs(skb->vlan_proto); 2014 status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID; 2015 } else { 2016 h.h2->tp_vlan_tci = 0; 2017 h.h2->tp_vlan_tpid = 0; 2018 } 2019 memset(h.h2->tp_padding, 0, sizeof(h.h2->tp_padding)); 2020 hdrlen = sizeof(*h.h2); 2021 break; 2022 case TPACKET_V3: 2023 /* tp_nxt_offset,vlan are already populated above. 2024 * So DONT clear those fields here 2025 */ 2026 h.h3->tp_status |= status; 2027 h.h3->tp_len = skb->len; 2028 h.h3->tp_snaplen = snaplen; 2029 h.h3->tp_mac = macoff; 2030 h.h3->tp_net = netoff; 2031 h.h3->tp_sec = ts.tv_sec; 2032 h.h3->tp_nsec = ts.tv_nsec; 2033 memset(h.h3->tp_padding, 0, sizeof(h.h3->tp_padding)); 2034 hdrlen = sizeof(*h.h3); 2035 break; 2036 default: 2037 BUG(); 2038 } 2039 2040 sll = h.raw + TPACKET_ALIGN(hdrlen); 2041 sll->sll_halen = dev_parse_header(skb, sll->sll_addr); 2042 sll->sll_family = AF_PACKET; 2043 sll->sll_hatype = dev->type; 2044 sll->sll_protocol = skb->protocol; 2045 sll->sll_pkttype = skb->pkt_type; 2046 if (unlikely(po->origdev)) 2047 sll->sll_ifindex = orig_dev->ifindex; 2048 else 2049 sll->sll_ifindex = dev->ifindex; 2050 2051 smp_mb(); 2052 2053 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1 2054 if (po->tp_version <= TPACKET_V2) { 2055 u8 *start, *end; 2056 2057 end = (u8 *) PAGE_ALIGN((unsigned long) h.raw + 2058 macoff + snaplen); 2059 2060 for (start = h.raw; start < end; start += PAGE_SIZE) 2061 flush_dcache_page(pgv_to_page(start)); 2062 } 2063 smp_wmb(); 2064 #endif 2065 2066 if (po->tp_version <= TPACKET_V2) { 2067 __packet_set_status(po, h.raw, status); 2068 sk->sk_data_ready(sk); 2069 } else { 2070 prb_clear_blk_fill_status(&po->rx_ring); 2071 } 2072 2073 drop_n_restore: 2074 if (skb_head != skb->data && skb_shared(skb)) { 2075 skb->data = skb_head; 2076 skb->len = skb_len; 2077 } 2078 drop: 2079 kfree_skb(skb); 2080 return 0; 2081 2082 ring_is_full: 2083 po->stats.stats1.tp_drops++; 2084 spin_unlock(&sk->sk_receive_queue.lock); 2085 2086 sk->sk_data_ready(sk); 2087 kfree_skb(copy_skb); 2088 goto drop_n_restore; 2089 } 2090 2091 static void tpacket_destruct_skb(struct sk_buff *skb) 2092 { 2093 struct packet_sock *po = pkt_sk(skb->sk); 2094 2095 if (likely(po->tx_ring.pg_vec)) { 2096 void *ph; 2097 __u32 ts; 2098 2099 ph = skb_shinfo(skb)->destructor_arg; 2100 packet_dec_pending(&po->tx_ring); 2101 2102 ts = __packet_set_timestamp(po, ph, skb); 2103 __packet_set_status(po, ph, TP_STATUS_AVAILABLE | ts); 2104 } 2105 2106 sock_wfree(skb); 2107 } 2108 2109 static bool ll_header_truncated(const struct net_device *dev, int len) 2110 { 2111 /* net device doesn't like empty head */ 2112 if (unlikely(len <= dev->hard_header_len)) { 2113 net_warn_ratelimited("%s: packet size is too short (%d <= %d)\n", 2114 current->comm, len, dev->hard_header_len); 2115 return true; 2116 } 2117 2118 return false; 2119 } 2120 2121 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb, 2122 void *frame, struct net_device *dev, int size_max, 2123 __be16 proto, unsigned char *addr, int hlen) 2124 { 2125 union tpacket_uhdr ph; 2126 int to_write, offset, len, tp_len, nr_frags, len_max; 2127 struct socket *sock = po->sk.sk_socket; 2128 struct page *page; 2129 void *data; 2130 int err; 2131 2132 ph.raw = frame; 2133 2134 skb->protocol = proto; 2135 skb->dev = dev; 2136 skb->priority = po->sk.sk_priority; 2137 skb->mark = po->sk.sk_mark; 2138 sock_tx_timestamp(&po->sk, &skb_shinfo(skb)->tx_flags); 2139 skb_shinfo(skb)->destructor_arg = ph.raw; 2140 2141 switch (po->tp_version) { 2142 case TPACKET_V2: 2143 tp_len = ph.h2->tp_len; 2144 break; 2145 default: 2146 tp_len = ph.h1->tp_len; 2147 break; 2148 } 2149 if (unlikely(tp_len > size_max)) { 2150 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max); 2151 return -EMSGSIZE; 2152 } 2153 2154 skb_reserve(skb, hlen); 2155 skb_reset_network_header(skb); 2156 2157 if (!packet_use_direct_xmit(po)) 2158 skb_probe_transport_header(skb, 0); 2159 if (unlikely(po->tp_tx_has_off)) { 2160 int off_min, off_max, off; 2161 off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll); 2162 off_max = po->tx_ring.frame_size - tp_len; 2163 if (sock->type == SOCK_DGRAM) { 2164 switch (po->tp_version) { 2165 case TPACKET_V2: 2166 off = ph.h2->tp_net; 2167 break; 2168 default: 2169 off = ph.h1->tp_net; 2170 break; 2171 } 2172 } else { 2173 switch (po->tp_version) { 2174 case TPACKET_V2: 2175 off = ph.h2->tp_mac; 2176 break; 2177 default: 2178 off = ph.h1->tp_mac; 2179 break; 2180 } 2181 } 2182 if (unlikely((off < off_min) || (off_max < off))) 2183 return -EINVAL; 2184 data = ph.raw + off; 2185 } else { 2186 data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll); 2187 } 2188 to_write = tp_len; 2189 2190 if (sock->type == SOCK_DGRAM) { 2191 err = dev_hard_header(skb, dev, ntohs(proto), addr, 2192 NULL, tp_len); 2193 if (unlikely(err < 0)) 2194 return -EINVAL; 2195 } else if (dev->hard_header_len) { 2196 if (ll_header_truncated(dev, tp_len)) 2197 return -EINVAL; 2198 2199 skb_push(skb, dev->hard_header_len); 2200 err = skb_store_bits(skb, 0, data, 2201 dev->hard_header_len); 2202 if (unlikely(err)) 2203 return err; 2204 2205 data += dev->hard_header_len; 2206 to_write -= dev->hard_header_len; 2207 } 2208 2209 offset = offset_in_page(data); 2210 len_max = PAGE_SIZE - offset; 2211 len = ((to_write > len_max) ? len_max : to_write); 2212 2213 skb->data_len = to_write; 2214 skb->len += to_write; 2215 skb->truesize += to_write; 2216 atomic_add(to_write, &po->sk.sk_wmem_alloc); 2217 2218 while (likely(to_write)) { 2219 nr_frags = skb_shinfo(skb)->nr_frags; 2220 2221 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) { 2222 pr_err("Packet exceed the number of skb frags(%lu)\n", 2223 MAX_SKB_FRAGS); 2224 return -EFAULT; 2225 } 2226 2227 page = pgv_to_page(data); 2228 data += len; 2229 flush_dcache_page(page); 2230 get_page(page); 2231 skb_fill_page_desc(skb, nr_frags, page, offset, len); 2232 to_write -= len; 2233 offset = 0; 2234 len_max = PAGE_SIZE; 2235 len = ((to_write > len_max) ? len_max : to_write); 2236 } 2237 2238 return tp_len; 2239 } 2240 2241 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg) 2242 { 2243 struct sk_buff *skb; 2244 struct net_device *dev; 2245 __be16 proto; 2246 int err, reserve = 0; 2247 void *ph; 2248 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name); 2249 bool need_wait = !(msg->msg_flags & MSG_DONTWAIT); 2250 int tp_len, size_max; 2251 unsigned char *addr; 2252 int len_sum = 0; 2253 int status = TP_STATUS_AVAILABLE; 2254 int hlen, tlen; 2255 2256 mutex_lock(&po->pg_vec_lock); 2257 2258 if (likely(saddr == NULL)) { 2259 dev = packet_cached_dev_get(po); 2260 proto = po->num; 2261 addr = NULL; 2262 } else { 2263 err = -EINVAL; 2264 if (msg->msg_namelen < sizeof(struct sockaddr_ll)) 2265 goto out; 2266 if (msg->msg_namelen < (saddr->sll_halen 2267 + offsetof(struct sockaddr_ll, 2268 sll_addr))) 2269 goto out; 2270 proto = saddr->sll_protocol; 2271 addr = saddr->sll_addr; 2272 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex); 2273 } 2274 2275 err = -ENXIO; 2276 if (unlikely(dev == NULL)) 2277 goto out; 2278 err = -ENETDOWN; 2279 if (unlikely(!(dev->flags & IFF_UP))) 2280 goto out_put; 2281 2282 reserve = dev->hard_header_len + VLAN_HLEN; 2283 size_max = po->tx_ring.frame_size 2284 - (po->tp_hdrlen - sizeof(struct sockaddr_ll)); 2285 2286 if (size_max > dev->mtu + reserve) 2287 size_max = dev->mtu + reserve; 2288 2289 do { 2290 ph = packet_current_frame(po, &po->tx_ring, 2291 TP_STATUS_SEND_REQUEST); 2292 if (unlikely(ph == NULL)) { 2293 if (need_wait && need_resched()) 2294 schedule(); 2295 continue; 2296 } 2297 2298 status = TP_STATUS_SEND_REQUEST; 2299 hlen = LL_RESERVED_SPACE(dev); 2300 tlen = dev->needed_tailroom; 2301 skb = sock_alloc_send_skb(&po->sk, 2302 hlen + tlen + sizeof(struct sockaddr_ll), 2303 0, &err); 2304 2305 if (unlikely(skb == NULL)) 2306 goto out_status; 2307 2308 tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto, 2309 addr, hlen); 2310 if (tp_len > dev->mtu + dev->hard_header_len) { 2311 struct ethhdr *ehdr; 2312 /* Earlier code assumed this would be a VLAN pkt, 2313 * double-check this now that we have the actual 2314 * packet in hand. 2315 */ 2316 2317 skb_reset_mac_header(skb); 2318 ehdr = eth_hdr(skb); 2319 if (ehdr->h_proto != htons(ETH_P_8021Q)) 2320 tp_len = -EMSGSIZE; 2321 } 2322 if (unlikely(tp_len < 0)) { 2323 if (po->tp_loss) { 2324 __packet_set_status(po, ph, 2325 TP_STATUS_AVAILABLE); 2326 packet_increment_head(&po->tx_ring); 2327 kfree_skb(skb); 2328 continue; 2329 } else { 2330 status = TP_STATUS_WRONG_FORMAT; 2331 err = tp_len; 2332 goto out_status; 2333 } 2334 } 2335 2336 packet_pick_tx_queue(dev, skb); 2337 2338 skb->destructor = tpacket_destruct_skb; 2339 __packet_set_status(po, ph, TP_STATUS_SENDING); 2340 packet_inc_pending(&po->tx_ring); 2341 2342 status = TP_STATUS_SEND_REQUEST; 2343 err = po->xmit(skb); 2344 if (unlikely(err > 0)) { 2345 err = net_xmit_errno(err); 2346 if (err && __packet_get_status(po, ph) == 2347 TP_STATUS_AVAILABLE) { 2348 /* skb was destructed already */ 2349 skb = NULL; 2350 goto out_status; 2351 } 2352 /* 2353 * skb was dropped but not destructed yet; 2354 * let's treat it like congestion or err < 0 2355 */ 2356 err = 0; 2357 } 2358 packet_increment_head(&po->tx_ring); 2359 len_sum += tp_len; 2360 } while (likely((ph != NULL) || 2361 /* Note: packet_read_pending() might be slow if we have 2362 * to call it as it's per_cpu variable, but in fast-path 2363 * we already short-circuit the loop with the first 2364 * condition, and luckily don't have to go that path 2365 * anyway. 2366 */ 2367 (need_wait && packet_read_pending(&po->tx_ring)))); 2368 2369 err = len_sum; 2370 goto out_put; 2371 2372 out_status: 2373 __packet_set_status(po, ph, status); 2374 kfree_skb(skb); 2375 out_put: 2376 dev_put(dev); 2377 out: 2378 mutex_unlock(&po->pg_vec_lock); 2379 return err; 2380 } 2381 2382 static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad, 2383 size_t reserve, size_t len, 2384 size_t linear, int noblock, 2385 int *err) 2386 { 2387 struct sk_buff *skb; 2388 2389 /* Under a page? Don't bother with paged skb. */ 2390 if (prepad + len < PAGE_SIZE || !linear) 2391 linear = len; 2392 2393 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock, 2394 err, 0); 2395 if (!skb) 2396 return NULL; 2397 2398 skb_reserve(skb, reserve); 2399 skb_put(skb, linear); 2400 skb->data_len = len - linear; 2401 skb->len += len - linear; 2402 2403 return skb; 2404 } 2405 2406 static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len) 2407 { 2408 struct sock *sk = sock->sk; 2409 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name); 2410 struct sk_buff *skb; 2411 struct net_device *dev; 2412 __be16 proto; 2413 unsigned char *addr; 2414 int err, reserve = 0; 2415 struct virtio_net_hdr vnet_hdr = { 0 }; 2416 int offset = 0; 2417 int vnet_hdr_len; 2418 struct packet_sock *po = pkt_sk(sk); 2419 unsigned short gso_type = 0; 2420 int hlen, tlen; 2421 int extra_len = 0; 2422 ssize_t n; 2423 2424 /* 2425 * Get and verify the address. 2426 */ 2427 2428 if (likely(saddr == NULL)) { 2429 dev = packet_cached_dev_get(po); 2430 proto = po->num; 2431 addr = NULL; 2432 } else { 2433 err = -EINVAL; 2434 if (msg->msg_namelen < sizeof(struct sockaddr_ll)) 2435 goto out; 2436 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr))) 2437 goto out; 2438 proto = saddr->sll_protocol; 2439 addr = saddr->sll_addr; 2440 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex); 2441 } 2442 2443 err = -ENXIO; 2444 if (unlikely(dev == NULL)) 2445 goto out_unlock; 2446 err = -ENETDOWN; 2447 if (unlikely(!(dev->flags & IFF_UP))) 2448 goto out_unlock; 2449 2450 if (sock->type == SOCK_RAW) 2451 reserve = dev->hard_header_len; 2452 if (po->has_vnet_hdr) { 2453 vnet_hdr_len = sizeof(vnet_hdr); 2454 2455 err = -EINVAL; 2456 if (len < vnet_hdr_len) 2457 goto out_unlock; 2458 2459 len -= vnet_hdr_len; 2460 2461 err = -EFAULT; 2462 n = copy_from_iter(&vnet_hdr, vnet_hdr_len, &msg->msg_iter); 2463 if (n != vnet_hdr_len) 2464 goto out_unlock; 2465 2466 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && 2467 (__virtio16_to_cpu(false, vnet_hdr.csum_start) + 2468 __virtio16_to_cpu(false, vnet_hdr.csum_offset) + 2 > 2469 __virtio16_to_cpu(false, vnet_hdr.hdr_len))) 2470 vnet_hdr.hdr_len = __cpu_to_virtio16(false, 2471 __virtio16_to_cpu(false, vnet_hdr.csum_start) + 2472 __virtio16_to_cpu(false, vnet_hdr.csum_offset) + 2); 2473 2474 err = -EINVAL; 2475 if (__virtio16_to_cpu(false, vnet_hdr.hdr_len) > len) 2476 goto out_unlock; 2477 2478 if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) { 2479 switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { 2480 case VIRTIO_NET_HDR_GSO_TCPV4: 2481 gso_type = SKB_GSO_TCPV4; 2482 break; 2483 case VIRTIO_NET_HDR_GSO_TCPV6: 2484 gso_type = SKB_GSO_TCPV6; 2485 break; 2486 case VIRTIO_NET_HDR_GSO_UDP: 2487 gso_type = SKB_GSO_UDP; 2488 break; 2489 default: 2490 goto out_unlock; 2491 } 2492 2493 if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN) 2494 gso_type |= SKB_GSO_TCP_ECN; 2495 2496 if (vnet_hdr.gso_size == 0) 2497 goto out_unlock; 2498 2499 } 2500 } 2501 2502 if (unlikely(sock_flag(sk, SOCK_NOFCS))) { 2503 if (!netif_supports_nofcs(dev)) { 2504 err = -EPROTONOSUPPORT; 2505 goto out_unlock; 2506 } 2507 extra_len = 4; /* We're doing our own CRC */ 2508 } 2509 2510 err = -EMSGSIZE; 2511 if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN + extra_len)) 2512 goto out_unlock; 2513 2514 err = -ENOBUFS; 2515 hlen = LL_RESERVED_SPACE(dev); 2516 tlen = dev->needed_tailroom; 2517 skb = packet_alloc_skb(sk, hlen + tlen, hlen, len, 2518 __virtio16_to_cpu(false, vnet_hdr.hdr_len), 2519 msg->msg_flags & MSG_DONTWAIT, &err); 2520 if (skb == NULL) 2521 goto out_unlock; 2522 2523 skb_set_network_header(skb, reserve); 2524 2525 err = -EINVAL; 2526 if (sock->type == SOCK_DGRAM) { 2527 offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len); 2528 if (unlikely(offset < 0)) 2529 goto out_free; 2530 } else { 2531 if (ll_header_truncated(dev, len)) 2532 goto out_free; 2533 } 2534 2535 /* Returns -EFAULT on error */ 2536 err = skb_copy_datagram_from_iter(skb, offset, &msg->msg_iter, len); 2537 if (err) 2538 goto out_free; 2539 2540 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags); 2541 2542 if (!gso_type && (len > dev->mtu + reserve + extra_len)) { 2543 /* Earlier code assumed this would be a VLAN pkt, 2544 * double-check this now that we have the actual 2545 * packet in hand. 2546 */ 2547 struct ethhdr *ehdr; 2548 skb_reset_mac_header(skb); 2549 ehdr = eth_hdr(skb); 2550 if (ehdr->h_proto != htons(ETH_P_8021Q)) { 2551 err = -EMSGSIZE; 2552 goto out_free; 2553 } 2554 } 2555 2556 skb->protocol = proto; 2557 skb->dev = dev; 2558 skb->priority = sk->sk_priority; 2559 skb->mark = sk->sk_mark; 2560 2561 packet_pick_tx_queue(dev, skb); 2562 2563 if (po->has_vnet_hdr) { 2564 if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) { 2565 u16 s = __virtio16_to_cpu(false, vnet_hdr.csum_start); 2566 u16 o = __virtio16_to_cpu(false, vnet_hdr.csum_offset); 2567 if (!skb_partial_csum_set(skb, s, o)) { 2568 err = -EINVAL; 2569 goto out_free; 2570 } 2571 } 2572 2573 skb_shinfo(skb)->gso_size = 2574 __virtio16_to_cpu(false, vnet_hdr.gso_size); 2575 skb_shinfo(skb)->gso_type = gso_type; 2576 2577 /* Header must be checked, and gso_segs computed. */ 2578 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY; 2579 skb_shinfo(skb)->gso_segs = 0; 2580 2581 len += vnet_hdr_len; 2582 } 2583 2584 if (!packet_use_direct_xmit(po)) 2585 skb_probe_transport_header(skb, reserve); 2586 if (unlikely(extra_len == 4)) 2587 skb->no_fcs = 1; 2588 2589 err = po->xmit(skb); 2590 if (err > 0 && (err = net_xmit_errno(err)) != 0) 2591 goto out_unlock; 2592 2593 dev_put(dev); 2594 2595 return len; 2596 2597 out_free: 2598 kfree_skb(skb); 2599 out_unlock: 2600 if (dev) 2601 dev_put(dev); 2602 out: 2603 return err; 2604 } 2605 2606 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock, 2607 struct msghdr *msg, size_t len) 2608 { 2609 struct sock *sk = sock->sk; 2610 struct packet_sock *po = pkt_sk(sk); 2611 2612 if (po->tx_ring.pg_vec) 2613 return tpacket_snd(po, msg); 2614 else 2615 return packet_snd(sock, msg, len); 2616 } 2617 2618 /* 2619 * Close a PACKET socket. This is fairly simple. We immediately go 2620 * to 'closed' state and remove our protocol entry in the device list. 2621 */ 2622 2623 static int packet_release(struct socket *sock) 2624 { 2625 struct sock *sk = sock->sk; 2626 struct packet_sock *po; 2627 struct net *net; 2628 union tpacket_req_u req_u; 2629 2630 if (!sk) 2631 return 0; 2632 2633 net = sock_net(sk); 2634 po = pkt_sk(sk); 2635 2636 mutex_lock(&net->packet.sklist_lock); 2637 sk_del_node_init_rcu(sk); 2638 mutex_unlock(&net->packet.sklist_lock); 2639 2640 preempt_disable(); 2641 sock_prot_inuse_add(net, sk->sk_prot, -1); 2642 preempt_enable(); 2643 2644 spin_lock(&po->bind_lock); 2645 unregister_prot_hook(sk, false); 2646 packet_cached_dev_reset(po); 2647 2648 if (po->prot_hook.dev) { 2649 dev_put(po->prot_hook.dev); 2650 po->prot_hook.dev = NULL; 2651 } 2652 spin_unlock(&po->bind_lock); 2653 2654 packet_flush_mclist(sk); 2655 2656 if (po->rx_ring.pg_vec) { 2657 memset(&req_u, 0, sizeof(req_u)); 2658 packet_set_ring(sk, &req_u, 1, 0); 2659 } 2660 2661 if (po->tx_ring.pg_vec) { 2662 memset(&req_u, 0, sizeof(req_u)); 2663 packet_set_ring(sk, &req_u, 1, 1); 2664 } 2665 2666 fanout_release(sk); 2667 2668 synchronize_net(); 2669 /* 2670 * Now the socket is dead. No more input will appear. 2671 */ 2672 sock_orphan(sk); 2673 sock->sk = NULL; 2674 2675 /* Purge queues */ 2676 2677 skb_queue_purge(&sk->sk_receive_queue); 2678 packet_free_pending(po); 2679 sk_refcnt_debug_release(sk); 2680 2681 sock_put(sk); 2682 return 0; 2683 } 2684 2685 /* 2686 * Attach a packet hook. 2687 */ 2688 2689 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 proto) 2690 { 2691 struct packet_sock *po = pkt_sk(sk); 2692 const struct net_device *dev_curr; 2693 __be16 proto_curr; 2694 bool need_rehook; 2695 2696 if (po->fanout) { 2697 if (dev) 2698 dev_put(dev); 2699 2700 return -EINVAL; 2701 } 2702 2703 lock_sock(sk); 2704 spin_lock(&po->bind_lock); 2705 2706 proto_curr = po->prot_hook.type; 2707 dev_curr = po->prot_hook.dev; 2708 2709 need_rehook = proto_curr != proto || dev_curr != dev; 2710 2711 if (need_rehook) { 2712 unregister_prot_hook(sk, true); 2713 2714 po->num = proto; 2715 po->prot_hook.type = proto; 2716 2717 if (po->prot_hook.dev) 2718 dev_put(po->prot_hook.dev); 2719 2720 po->prot_hook.dev = dev; 2721 2722 po->ifindex = dev ? dev->ifindex : 0; 2723 packet_cached_dev_assign(po, dev); 2724 } 2725 2726 if (proto == 0 || !need_rehook) 2727 goto out_unlock; 2728 2729 if (!dev || (dev->flags & IFF_UP)) { 2730 register_prot_hook(sk); 2731 } else { 2732 sk->sk_err = ENETDOWN; 2733 if (!sock_flag(sk, SOCK_DEAD)) 2734 sk->sk_error_report(sk); 2735 } 2736 2737 out_unlock: 2738 spin_unlock(&po->bind_lock); 2739 release_sock(sk); 2740 return 0; 2741 } 2742 2743 /* 2744 * Bind a packet socket to a device 2745 */ 2746 2747 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr, 2748 int addr_len) 2749 { 2750 struct sock *sk = sock->sk; 2751 char name[15]; 2752 struct net_device *dev; 2753 int err = -ENODEV; 2754 2755 /* 2756 * Check legality 2757 */ 2758 2759 if (addr_len != sizeof(struct sockaddr)) 2760 return -EINVAL; 2761 strlcpy(name, uaddr->sa_data, sizeof(name)); 2762 2763 dev = dev_get_by_name(sock_net(sk), name); 2764 if (dev) 2765 err = packet_do_bind(sk, dev, pkt_sk(sk)->num); 2766 return err; 2767 } 2768 2769 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) 2770 { 2771 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr; 2772 struct sock *sk = sock->sk; 2773 struct net_device *dev = NULL; 2774 int err; 2775 2776 2777 /* 2778 * Check legality 2779 */ 2780 2781 if (addr_len < sizeof(struct sockaddr_ll)) 2782 return -EINVAL; 2783 if (sll->sll_family != AF_PACKET) 2784 return -EINVAL; 2785 2786 if (sll->sll_ifindex) { 2787 err = -ENODEV; 2788 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex); 2789 if (dev == NULL) 2790 goto out; 2791 } 2792 err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num); 2793 2794 out: 2795 return err; 2796 } 2797 2798 static struct proto packet_proto = { 2799 .name = "PACKET", 2800 .owner = THIS_MODULE, 2801 .obj_size = sizeof(struct packet_sock), 2802 }; 2803 2804 /* 2805 * Create a packet of type SOCK_PACKET. 2806 */ 2807 2808 static int packet_create(struct net *net, struct socket *sock, int protocol, 2809 int kern) 2810 { 2811 struct sock *sk; 2812 struct packet_sock *po; 2813 __be16 proto = (__force __be16)protocol; /* weird, but documented */ 2814 int err; 2815 2816 if (!ns_capable(net->user_ns, CAP_NET_RAW)) 2817 return -EPERM; 2818 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW && 2819 sock->type != SOCK_PACKET) 2820 return -ESOCKTNOSUPPORT; 2821 2822 sock->state = SS_UNCONNECTED; 2823 2824 err = -ENOBUFS; 2825 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto); 2826 if (sk == NULL) 2827 goto out; 2828 2829 sock->ops = &packet_ops; 2830 if (sock->type == SOCK_PACKET) 2831 sock->ops = &packet_ops_spkt; 2832 2833 sock_init_data(sock, sk); 2834 2835 po = pkt_sk(sk); 2836 sk->sk_family = PF_PACKET; 2837 po->num = proto; 2838 po->xmit = dev_queue_xmit; 2839 2840 err = packet_alloc_pending(po); 2841 if (err) 2842 goto out2; 2843 2844 packet_cached_dev_reset(po); 2845 2846 sk->sk_destruct = packet_sock_destruct; 2847 sk_refcnt_debug_inc(sk); 2848 2849 /* 2850 * Attach a protocol block 2851 */ 2852 2853 spin_lock_init(&po->bind_lock); 2854 mutex_init(&po->pg_vec_lock); 2855 po->prot_hook.func = packet_rcv; 2856 2857 if (sock->type == SOCK_PACKET) 2858 po->prot_hook.func = packet_rcv_spkt; 2859 2860 po->prot_hook.af_packet_priv = sk; 2861 2862 if (proto) { 2863 po->prot_hook.type = proto; 2864 register_prot_hook(sk); 2865 } 2866 2867 mutex_lock(&net->packet.sklist_lock); 2868 sk_add_node_rcu(sk, &net->packet.sklist); 2869 mutex_unlock(&net->packet.sklist_lock); 2870 2871 preempt_disable(); 2872 sock_prot_inuse_add(net, &packet_proto, 1); 2873 preempt_enable(); 2874 2875 return 0; 2876 out2: 2877 sk_free(sk); 2878 out: 2879 return err; 2880 } 2881 2882 /* 2883 * Pull a packet from our receive queue and hand it to the user. 2884 * If necessary we block. 2885 */ 2886 2887 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock, 2888 struct msghdr *msg, size_t len, int flags) 2889 { 2890 struct sock *sk = sock->sk; 2891 struct sk_buff *skb; 2892 int copied, err; 2893 int vnet_hdr_len = 0; 2894 2895 err = -EINVAL; 2896 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE)) 2897 goto out; 2898 2899 #if 0 2900 /* What error should we return now? EUNATTACH? */ 2901 if (pkt_sk(sk)->ifindex < 0) 2902 return -ENODEV; 2903 #endif 2904 2905 if (flags & MSG_ERRQUEUE) { 2906 err = sock_recv_errqueue(sk, msg, len, 2907 SOL_PACKET, PACKET_TX_TIMESTAMP); 2908 goto out; 2909 } 2910 2911 /* 2912 * Call the generic datagram receiver. This handles all sorts 2913 * of horrible races and re-entrancy so we can forget about it 2914 * in the protocol layers. 2915 * 2916 * Now it will return ENETDOWN, if device have just gone down, 2917 * but then it will block. 2918 */ 2919 2920 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err); 2921 2922 /* 2923 * An error occurred so return it. Because skb_recv_datagram() 2924 * handles the blocking we don't see and worry about blocking 2925 * retries. 2926 */ 2927 2928 if (skb == NULL) 2929 goto out; 2930 2931 if (pkt_sk(sk)->has_vnet_hdr) { 2932 struct virtio_net_hdr vnet_hdr = { 0 }; 2933 2934 err = -EINVAL; 2935 vnet_hdr_len = sizeof(vnet_hdr); 2936 if (len < vnet_hdr_len) 2937 goto out_free; 2938 2939 len -= vnet_hdr_len; 2940 2941 if (skb_is_gso(skb)) { 2942 struct skb_shared_info *sinfo = skb_shinfo(skb); 2943 2944 /* This is a hint as to how much should be linear. */ 2945 vnet_hdr.hdr_len = 2946 __cpu_to_virtio16(false, skb_headlen(skb)); 2947 vnet_hdr.gso_size = 2948 __cpu_to_virtio16(false, sinfo->gso_size); 2949 if (sinfo->gso_type & SKB_GSO_TCPV4) 2950 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4; 2951 else if (sinfo->gso_type & SKB_GSO_TCPV6) 2952 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6; 2953 else if (sinfo->gso_type & SKB_GSO_UDP) 2954 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP; 2955 else if (sinfo->gso_type & SKB_GSO_FCOE) 2956 goto out_free; 2957 else 2958 BUG(); 2959 if (sinfo->gso_type & SKB_GSO_TCP_ECN) 2960 vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN; 2961 } else 2962 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE; 2963 2964 if (skb->ip_summed == CHECKSUM_PARTIAL) { 2965 vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; 2966 vnet_hdr.csum_start = __cpu_to_virtio16(false, 2967 skb_checksum_start_offset(skb)); 2968 vnet_hdr.csum_offset = __cpu_to_virtio16(false, 2969 skb->csum_offset); 2970 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) { 2971 vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID; 2972 } /* else everything is zero */ 2973 2974 err = memcpy_to_msg(msg, (void *)&vnet_hdr, vnet_hdr_len); 2975 if (err < 0) 2976 goto out_free; 2977 } 2978 2979 /* You lose any data beyond the buffer you gave. If it worries 2980 * a user program they can ask the device for its MTU 2981 * anyway. 2982 */ 2983 copied = skb->len; 2984 if (copied > len) { 2985 copied = len; 2986 msg->msg_flags |= MSG_TRUNC; 2987 } 2988 2989 err = skb_copy_datagram_msg(skb, 0, msg, copied); 2990 if (err) 2991 goto out_free; 2992 2993 sock_recv_ts_and_drops(msg, sk, skb); 2994 2995 if (msg->msg_name) { 2996 /* If the address length field is there to be filled 2997 * in, we fill it in now. 2998 */ 2999 if (sock->type == SOCK_PACKET) { 3000 __sockaddr_check_size(sizeof(struct sockaddr_pkt)); 3001 msg->msg_namelen = sizeof(struct sockaddr_pkt); 3002 } else { 3003 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll; 3004 msg->msg_namelen = sll->sll_halen + 3005 offsetof(struct sockaddr_ll, sll_addr); 3006 } 3007 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa, 3008 msg->msg_namelen); 3009 } 3010 3011 if (pkt_sk(sk)->auxdata) { 3012 struct tpacket_auxdata aux; 3013 3014 aux.tp_status = TP_STATUS_USER; 3015 if (skb->ip_summed == CHECKSUM_PARTIAL) 3016 aux.tp_status |= TP_STATUS_CSUMNOTREADY; 3017 aux.tp_len = PACKET_SKB_CB(skb)->origlen; 3018 aux.tp_snaplen = skb->len; 3019 aux.tp_mac = 0; 3020 aux.tp_net = skb_network_offset(skb); 3021 if (skb_vlan_tag_present(skb)) { 3022 aux.tp_vlan_tci = skb_vlan_tag_get(skb); 3023 aux.tp_vlan_tpid = ntohs(skb->vlan_proto); 3024 aux.tp_status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID; 3025 } else { 3026 aux.tp_vlan_tci = 0; 3027 aux.tp_vlan_tpid = 0; 3028 } 3029 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux); 3030 } 3031 3032 /* 3033 * Free or return the buffer as appropriate. Again this 3034 * hides all the races and re-entrancy issues from us. 3035 */ 3036 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied); 3037 3038 out_free: 3039 skb_free_datagram(sk, skb); 3040 out: 3041 return err; 3042 } 3043 3044 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr, 3045 int *uaddr_len, int peer) 3046 { 3047 struct net_device *dev; 3048 struct sock *sk = sock->sk; 3049 3050 if (peer) 3051 return -EOPNOTSUPP; 3052 3053 uaddr->sa_family = AF_PACKET; 3054 memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data)); 3055 rcu_read_lock(); 3056 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex); 3057 if (dev) 3058 strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data)); 3059 rcu_read_unlock(); 3060 *uaddr_len = sizeof(*uaddr); 3061 3062 return 0; 3063 } 3064 3065 static int packet_getname(struct socket *sock, struct sockaddr *uaddr, 3066 int *uaddr_len, int peer) 3067 { 3068 struct net_device *dev; 3069 struct sock *sk = sock->sk; 3070 struct packet_sock *po = pkt_sk(sk); 3071 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr); 3072 3073 if (peer) 3074 return -EOPNOTSUPP; 3075 3076 sll->sll_family = AF_PACKET; 3077 sll->sll_ifindex = po->ifindex; 3078 sll->sll_protocol = po->num; 3079 sll->sll_pkttype = 0; 3080 rcu_read_lock(); 3081 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex); 3082 if (dev) { 3083 sll->sll_hatype = dev->type; 3084 sll->sll_halen = dev->addr_len; 3085 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len); 3086 } else { 3087 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */ 3088 sll->sll_halen = 0; 3089 } 3090 rcu_read_unlock(); 3091 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen; 3092 3093 return 0; 3094 } 3095 3096 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i, 3097 int what) 3098 { 3099 switch (i->type) { 3100 case PACKET_MR_MULTICAST: 3101 if (i->alen != dev->addr_len) 3102 return -EINVAL; 3103 if (what > 0) 3104 return dev_mc_add(dev, i->addr); 3105 else 3106 return dev_mc_del(dev, i->addr); 3107 break; 3108 case PACKET_MR_PROMISC: 3109 return dev_set_promiscuity(dev, what); 3110 case PACKET_MR_ALLMULTI: 3111 return dev_set_allmulti(dev, what); 3112 case PACKET_MR_UNICAST: 3113 if (i->alen != dev->addr_len) 3114 return -EINVAL; 3115 if (what > 0) 3116 return dev_uc_add(dev, i->addr); 3117 else 3118 return dev_uc_del(dev, i->addr); 3119 break; 3120 default: 3121 break; 3122 } 3123 return 0; 3124 } 3125 3126 static void packet_dev_mclist_delete(struct net_device *dev, 3127 struct packet_mclist **mlp) 3128 { 3129 struct packet_mclist *ml; 3130 3131 while ((ml = *mlp) != NULL) { 3132 if (ml->ifindex == dev->ifindex) { 3133 packet_dev_mc(dev, ml, -1); 3134 *mlp = ml->next; 3135 kfree(ml); 3136 } else 3137 mlp = &ml->next; 3138 } 3139 } 3140 3141 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq) 3142 { 3143 struct packet_sock *po = pkt_sk(sk); 3144 struct packet_mclist *ml, *i; 3145 struct net_device *dev; 3146 int err; 3147 3148 rtnl_lock(); 3149 3150 err = -ENODEV; 3151 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex); 3152 if (!dev) 3153 goto done; 3154 3155 err = -EINVAL; 3156 if (mreq->mr_alen > dev->addr_len) 3157 goto done; 3158 3159 err = -ENOBUFS; 3160 i = kmalloc(sizeof(*i), GFP_KERNEL); 3161 if (i == NULL) 3162 goto done; 3163 3164 err = 0; 3165 for (ml = po->mclist; ml; ml = ml->next) { 3166 if (ml->ifindex == mreq->mr_ifindex && 3167 ml->type == mreq->mr_type && 3168 ml->alen == mreq->mr_alen && 3169 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) { 3170 ml->count++; 3171 /* Free the new element ... */ 3172 kfree(i); 3173 goto done; 3174 } 3175 } 3176 3177 i->type = mreq->mr_type; 3178 i->ifindex = mreq->mr_ifindex; 3179 i->alen = mreq->mr_alen; 3180 memcpy(i->addr, mreq->mr_address, i->alen); 3181 i->count = 1; 3182 i->next = po->mclist; 3183 po->mclist = i; 3184 err = packet_dev_mc(dev, i, 1); 3185 if (err) { 3186 po->mclist = i->next; 3187 kfree(i); 3188 } 3189 3190 done: 3191 rtnl_unlock(); 3192 return err; 3193 } 3194 3195 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq) 3196 { 3197 struct packet_mclist *ml, **mlp; 3198 3199 rtnl_lock(); 3200 3201 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) { 3202 if (ml->ifindex == mreq->mr_ifindex && 3203 ml->type == mreq->mr_type && 3204 ml->alen == mreq->mr_alen && 3205 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) { 3206 if (--ml->count == 0) { 3207 struct net_device *dev; 3208 *mlp = ml->next; 3209 dev = __dev_get_by_index(sock_net(sk), ml->ifindex); 3210 if (dev) 3211 packet_dev_mc(dev, ml, -1); 3212 kfree(ml); 3213 } 3214 break; 3215 } 3216 } 3217 rtnl_unlock(); 3218 return 0; 3219 } 3220 3221 static void packet_flush_mclist(struct sock *sk) 3222 { 3223 struct packet_sock *po = pkt_sk(sk); 3224 struct packet_mclist *ml; 3225 3226 if (!po->mclist) 3227 return; 3228 3229 rtnl_lock(); 3230 while ((ml = po->mclist) != NULL) { 3231 struct net_device *dev; 3232 3233 po->mclist = ml->next; 3234 dev = __dev_get_by_index(sock_net(sk), ml->ifindex); 3235 if (dev != NULL) 3236 packet_dev_mc(dev, ml, -1); 3237 kfree(ml); 3238 } 3239 rtnl_unlock(); 3240 } 3241 3242 static int 3243 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen) 3244 { 3245 struct sock *sk = sock->sk; 3246 struct packet_sock *po = pkt_sk(sk); 3247 int ret; 3248 3249 if (level != SOL_PACKET) 3250 return -ENOPROTOOPT; 3251 3252 switch (optname) { 3253 case PACKET_ADD_MEMBERSHIP: 3254 case PACKET_DROP_MEMBERSHIP: 3255 { 3256 struct packet_mreq_max mreq; 3257 int len = optlen; 3258 memset(&mreq, 0, sizeof(mreq)); 3259 if (len < sizeof(struct packet_mreq)) 3260 return -EINVAL; 3261 if (len > sizeof(mreq)) 3262 len = sizeof(mreq); 3263 if (copy_from_user(&mreq, optval, len)) 3264 return -EFAULT; 3265 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address))) 3266 return -EINVAL; 3267 if (optname == PACKET_ADD_MEMBERSHIP) 3268 ret = packet_mc_add(sk, &mreq); 3269 else 3270 ret = packet_mc_drop(sk, &mreq); 3271 return ret; 3272 } 3273 3274 case PACKET_RX_RING: 3275 case PACKET_TX_RING: 3276 { 3277 union tpacket_req_u req_u; 3278 int len; 3279 3280 switch (po->tp_version) { 3281 case TPACKET_V1: 3282 case TPACKET_V2: 3283 len = sizeof(req_u.req); 3284 break; 3285 case TPACKET_V3: 3286 default: 3287 len = sizeof(req_u.req3); 3288 break; 3289 } 3290 if (optlen < len) 3291 return -EINVAL; 3292 if (pkt_sk(sk)->has_vnet_hdr) 3293 return -EINVAL; 3294 if (copy_from_user(&req_u.req, optval, len)) 3295 return -EFAULT; 3296 return packet_set_ring(sk, &req_u, 0, 3297 optname == PACKET_TX_RING); 3298 } 3299 case PACKET_COPY_THRESH: 3300 { 3301 int val; 3302 3303 if (optlen != sizeof(val)) 3304 return -EINVAL; 3305 if (copy_from_user(&val, optval, sizeof(val))) 3306 return -EFAULT; 3307 3308 pkt_sk(sk)->copy_thresh = val; 3309 return 0; 3310 } 3311 case PACKET_VERSION: 3312 { 3313 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 switch (val) { 3322 case TPACKET_V1: 3323 case TPACKET_V2: 3324 case TPACKET_V3: 3325 po->tp_version = val; 3326 return 0; 3327 default: 3328 return -EINVAL; 3329 } 3330 } 3331 case PACKET_RESERVE: 3332 { 3333 unsigned int val; 3334 3335 if (optlen != sizeof(val)) 3336 return -EINVAL; 3337 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 3338 return -EBUSY; 3339 if (copy_from_user(&val, optval, sizeof(val))) 3340 return -EFAULT; 3341 po->tp_reserve = val; 3342 return 0; 3343 } 3344 case PACKET_LOSS: 3345 { 3346 unsigned int val; 3347 3348 if (optlen != sizeof(val)) 3349 return -EINVAL; 3350 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 3351 return -EBUSY; 3352 if (copy_from_user(&val, optval, sizeof(val))) 3353 return -EFAULT; 3354 po->tp_loss = !!val; 3355 return 0; 3356 } 3357 case PACKET_AUXDATA: 3358 { 3359 int val; 3360 3361 if (optlen < sizeof(val)) 3362 return -EINVAL; 3363 if (copy_from_user(&val, optval, sizeof(val))) 3364 return -EFAULT; 3365 3366 po->auxdata = !!val; 3367 return 0; 3368 } 3369 case PACKET_ORIGDEV: 3370 { 3371 int val; 3372 3373 if (optlen < sizeof(val)) 3374 return -EINVAL; 3375 if (copy_from_user(&val, optval, sizeof(val))) 3376 return -EFAULT; 3377 3378 po->origdev = !!val; 3379 return 0; 3380 } 3381 case PACKET_VNET_HDR: 3382 { 3383 int val; 3384 3385 if (sock->type != SOCK_RAW) 3386 return -EINVAL; 3387 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 3388 return -EBUSY; 3389 if (optlen < sizeof(val)) 3390 return -EINVAL; 3391 if (copy_from_user(&val, optval, sizeof(val))) 3392 return -EFAULT; 3393 3394 po->has_vnet_hdr = !!val; 3395 return 0; 3396 } 3397 case PACKET_TIMESTAMP: 3398 { 3399 int val; 3400 3401 if (optlen != sizeof(val)) 3402 return -EINVAL; 3403 if (copy_from_user(&val, optval, sizeof(val))) 3404 return -EFAULT; 3405 3406 po->tp_tstamp = val; 3407 return 0; 3408 } 3409 case PACKET_FANOUT: 3410 { 3411 int val; 3412 3413 if (optlen != sizeof(val)) 3414 return -EINVAL; 3415 if (copy_from_user(&val, optval, sizeof(val))) 3416 return -EFAULT; 3417 3418 return fanout_add(sk, val & 0xffff, val >> 16); 3419 } 3420 case PACKET_TX_HAS_OFF: 3421 { 3422 unsigned int val; 3423 3424 if (optlen != sizeof(val)) 3425 return -EINVAL; 3426 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 3427 return -EBUSY; 3428 if (copy_from_user(&val, optval, sizeof(val))) 3429 return -EFAULT; 3430 po->tp_tx_has_off = !!val; 3431 return 0; 3432 } 3433 case PACKET_QDISC_BYPASS: 3434 { 3435 int val; 3436 3437 if (optlen != sizeof(val)) 3438 return -EINVAL; 3439 if (copy_from_user(&val, optval, sizeof(val))) 3440 return -EFAULT; 3441 3442 po->xmit = val ? packet_direct_xmit : dev_queue_xmit; 3443 return 0; 3444 } 3445 default: 3446 return -ENOPROTOOPT; 3447 } 3448 } 3449 3450 static int packet_getsockopt(struct socket *sock, int level, int optname, 3451 char __user *optval, int __user *optlen) 3452 { 3453 int len; 3454 int val, lv = sizeof(val); 3455 struct sock *sk = sock->sk; 3456 struct packet_sock *po = pkt_sk(sk); 3457 void *data = &val; 3458 union tpacket_stats_u st; 3459 3460 if (level != SOL_PACKET) 3461 return -ENOPROTOOPT; 3462 3463 if (get_user(len, optlen)) 3464 return -EFAULT; 3465 3466 if (len < 0) 3467 return -EINVAL; 3468 3469 switch (optname) { 3470 case PACKET_STATISTICS: 3471 spin_lock_bh(&sk->sk_receive_queue.lock); 3472 memcpy(&st, &po->stats, sizeof(st)); 3473 memset(&po->stats, 0, sizeof(po->stats)); 3474 spin_unlock_bh(&sk->sk_receive_queue.lock); 3475 3476 if (po->tp_version == TPACKET_V3) { 3477 lv = sizeof(struct tpacket_stats_v3); 3478 st.stats3.tp_packets += st.stats3.tp_drops; 3479 data = &st.stats3; 3480 } else { 3481 lv = sizeof(struct tpacket_stats); 3482 st.stats1.tp_packets += st.stats1.tp_drops; 3483 data = &st.stats1; 3484 } 3485 3486 break; 3487 case PACKET_AUXDATA: 3488 val = po->auxdata; 3489 break; 3490 case PACKET_ORIGDEV: 3491 val = po->origdev; 3492 break; 3493 case PACKET_VNET_HDR: 3494 val = po->has_vnet_hdr; 3495 break; 3496 case PACKET_VERSION: 3497 val = po->tp_version; 3498 break; 3499 case PACKET_HDRLEN: 3500 if (len > sizeof(int)) 3501 len = sizeof(int); 3502 if (copy_from_user(&val, optval, len)) 3503 return -EFAULT; 3504 switch (val) { 3505 case TPACKET_V1: 3506 val = sizeof(struct tpacket_hdr); 3507 break; 3508 case TPACKET_V2: 3509 val = sizeof(struct tpacket2_hdr); 3510 break; 3511 case TPACKET_V3: 3512 val = sizeof(struct tpacket3_hdr); 3513 break; 3514 default: 3515 return -EINVAL; 3516 } 3517 break; 3518 case PACKET_RESERVE: 3519 val = po->tp_reserve; 3520 break; 3521 case PACKET_LOSS: 3522 val = po->tp_loss; 3523 break; 3524 case PACKET_TIMESTAMP: 3525 val = po->tp_tstamp; 3526 break; 3527 case PACKET_FANOUT: 3528 val = (po->fanout ? 3529 ((u32)po->fanout->id | 3530 ((u32)po->fanout->type << 16) | 3531 ((u32)po->fanout->flags << 24)) : 3532 0); 3533 break; 3534 case PACKET_TX_HAS_OFF: 3535 val = po->tp_tx_has_off; 3536 break; 3537 case PACKET_QDISC_BYPASS: 3538 val = packet_use_direct_xmit(po); 3539 break; 3540 default: 3541 return -ENOPROTOOPT; 3542 } 3543 3544 if (len > lv) 3545 len = lv; 3546 if (put_user(len, optlen)) 3547 return -EFAULT; 3548 if (copy_to_user(optval, data, len)) 3549 return -EFAULT; 3550 return 0; 3551 } 3552 3553 3554 static int packet_notifier(struct notifier_block *this, 3555 unsigned long msg, void *ptr) 3556 { 3557 struct sock *sk; 3558 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 3559 struct net *net = dev_net(dev); 3560 3561 rcu_read_lock(); 3562 sk_for_each_rcu(sk, &net->packet.sklist) { 3563 struct packet_sock *po = pkt_sk(sk); 3564 3565 switch (msg) { 3566 case NETDEV_UNREGISTER: 3567 if (po->mclist) 3568 packet_dev_mclist_delete(dev, &po->mclist); 3569 /* fallthrough */ 3570 3571 case NETDEV_DOWN: 3572 if (dev->ifindex == po->ifindex) { 3573 spin_lock(&po->bind_lock); 3574 if (po->running) { 3575 __unregister_prot_hook(sk, false); 3576 sk->sk_err = ENETDOWN; 3577 if (!sock_flag(sk, SOCK_DEAD)) 3578 sk->sk_error_report(sk); 3579 } 3580 if (msg == NETDEV_UNREGISTER) { 3581 packet_cached_dev_reset(po); 3582 po->ifindex = -1; 3583 if (po->prot_hook.dev) 3584 dev_put(po->prot_hook.dev); 3585 po->prot_hook.dev = NULL; 3586 } 3587 spin_unlock(&po->bind_lock); 3588 } 3589 break; 3590 case NETDEV_UP: 3591 if (dev->ifindex == po->ifindex) { 3592 spin_lock(&po->bind_lock); 3593 if (po->num) 3594 register_prot_hook(sk); 3595 spin_unlock(&po->bind_lock); 3596 } 3597 break; 3598 } 3599 } 3600 rcu_read_unlock(); 3601 return NOTIFY_DONE; 3602 } 3603 3604 3605 static int packet_ioctl(struct socket *sock, unsigned int cmd, 3606 unsigned long arg) 3607 { 3608 struct sock *sk = sock->sk; 3609 3610 switch (cmd) { 3611 case SIOCOUTQ: 3612 { 3613 int amount = sk_wmem_alloc_get(sk); 3614 3615 return put_user(amount, (int __user *)arg); 3616 } 3617 case SIOCINQ: 3618 { 3619 struct sk_buff *skb; 3620 int amount = 0; 3621 3622 spin_lock_bh(&sk->sk_receive_queue.lock); 3623 skb = skb_peek(&sk->sk_receive_queue); 3624 if (skb) 3625 amount = skb->len; 3626 spin_unlock_bh(&sk->sk_receive_queue.lock); 3627 return put_user(amount, (int __user *)arg); 3628 } 3629 case SIOCGSTAMP: 3630 return sock_get_timestamp(sk, (struct timeval __user *)arg); 3631 case SIOCGSTAMPNS: 3632 return sock_get_timestampns(sk, (struct timespec __user *)arg); 3633 3634 #ifdef CONFIG_INET 3635 case SIOCADDRT: 3636 case SIOCDELRT: 3637 case SIOCDARP: 3638 case SIOCGARP: 3639 case SIOCSARP: 3640 case SIOCGIFADDR: 3641 case SIOCSIFADDR: 3642 case SIOCGIFBRDADDR: 3643 case SIOCSIFBRDADDR: 3644 case SIOCGIFNETMASK: 3645 case SIOCSIFNETMASK: 3646 case SIOCGIFDSTADDR: 3647 case SIOCSIFDSTADDR: 3648 case SIOCSIFFLAGS: 3649 return inet_dgram_ops.ioctl(sock, cmd, arg); 3650 #endif 3651 3652 default: 3653 return -ENOIOCTLCMD; 3654 } 3655 return 0; 3656 } 3657 3658 static unsigned int packet_poll(struct file *file, struct socket *sock, 3659 poll_table *wait) 3660 { 3661 struct sock *sk = sock->sk; 3662 struct packet_sock *po = pkt_sk(sk); 3663 unsigned int mask = datagram_poll(file, sock, wait); 3664 3665 spin_lock_bh(&sk->sk_receive_queue.lock); 3666 if (po->rx_ring.pg_vec) { 3667 if (!packet_previous_rx_frame(po, &po->rx_ring, 3668 TP_STATUS_KERNEL)) 3669 mask |= POLLIN | POLLRDNORM; 3670 } 3671 spin_unlock_bh(&sk->sk_receive_queue.lock); 3672 spin_lock_bh(&sk->sk_write_queue.lock); 3673 if (po->tx_ring.pg_vec) { 3674 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE)) 3675 mask |= POLLOUT | POLLWRNORM; 3676 } 3677 spin_unlock_bh(&sk->sk_write_queue.lock); 3678 return mask; 3679 } 3680 3681 3682 /* Dirty? Well, I still did not learn better way to account 3683 * for user mmaps. 3684 */ 3685 3686 static void packet_mm_open(struct vm_area_struct *vma) 3687 { 3688 struct file *file = vma->vm_file; 3689 struct socket *sock = file->private_data; 3690 struct sock *sk = sock->sk; 3691 3692 if (sk) 3693 atomic_inc(&pkt_sk(sk)->mapped); 3694 } 3695 3696 static void packet_mm_close(struct vm_area_struct *vma) 3697 { 3698 struct file *file = vma->vm_file; 3699 struct socket *sock = file->private_data; 3700 struct sock *sk = sock->sk; 3701 3702 if (sk) 3703 atomic_dec(&pkt_sk(sk)->mapped); 3704 } 3705 3706 static const struct vm_operations_struct packet_mmap_ops = { 3707 .open = packet_mm_open, 3708 .close = packet_mm_close, 3709 }; 3710 3711 static void free_pg_vec(struct pgv *pg_vec, unsigned int order, 3712 unsigned int len) 3713 { 3714 int i; 3715 3716 for (i = 0; i < len; i++) { 3717 if (likely(pg_vec[i].buffer)) { 3718 if (is_vmalloc_addr(pg_vec[i].buffer)) 3719 vfree(pg_vec[i].buffer); 3720 else 3721 free_pages((unsigned long)pg_vec[i].buffer, 3722 order); 3723 pg_vec[i].buffer = NULL; 3724 } 3725 } 3726 kfree(pg_vec); 3727 } 3728 3729 static char *alloc_one_pg_vec_page(unsigned long order) 3730 { 3731 char *buffer; 3732 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP | 3733 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY; 3734 3735 buffer = (char *) __get_free_pages(gfp_flags, order); 3736 if (buffer) 3737 return buffer; 3738 3739 /* __get_free_pages failed, fall back to vmalloc */ 3740 buffer = vzalloc((1 << order) * PAGE_SIZE); 3741 if (buffer) 3742 return buffer; 3743 3744 /* vmalloc failed, lets dig into swap here */ 3745 gfp_flags &= ~__GFP_NORETRY; 3746 buffer = (char *) __get_free_pages(gfp_flags, order); 3747 if (buffer) 3748 return buffer; 3749 3750 /* complete and utter failure */ 3751 return NULL; 3752 } 3753 3754 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order) 3755 { 3756 unsigned int block_nr = req->tp_block_nr; 3757 struct pgv *pg_vec; 3758 int i; 3759 3760 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL); 3761 if (unlikely(!pg_vec)) 3762 goto out; 3763 3764 for (i = 0; i < block_nr; i++) { 3765 pg_vec[i].buffer = alloc_one_pg_vec_page(order); 3766 if (unlikely(!pg_vec[i].buffer)) 3767 goto out_free_pgvec; 3768 } 3769 3770 out: 3771 return pg_vec; 3772 3773 out_free_pgvec: 3774 free_pg_vec(pg_vec, order, block_nr); 3775 pg_vec = NULL; 3776 goto out; 3777 } 3778 3779 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u, 3780 int closing, int tx_ring) 3781 { 3782 struct pgv *pg_vec = NULL; 3783 struct packet_sock *po = pkt_sk(sk); 3784 int was_running, order = 0; 3785 struct packet_ring_buffer *rb; 3786 struct sk_buff_head *rb_queue; 3787 __be16 num; 3788 int err = -EINVAL; 3789 /* Added to avoid minimal code churn */ 3790 struct tpacket_req *req = &req_u->req; 3791 3792 /* Opening a Tx-ring is NOT supported in TPACKET_V3 */ 3793 if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) { 3794 WARN(1, "Tx-ring is not supported.\n"); 3795 goto out; 3796 } 3797 3798 rb = tx_ring ? &po->tx_ring : &po->rx_ring; 3799 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue; 3800 3801 err = -EBUSY; 3802 if (!closing) { 3803 if (atomic_read(&po->mapped)) 3804 goto out; 3805 if (packet_read_pending(rb)) 3806 goto out; 3807 } 3808 3809 if (req->tp_block_nr) { 3810 /* Sanity tests and some calculations */ 3811 err = -EBUSY; 3812 if (unlikely(rb->pg_vec)) 3813 goto out; 3814 3815 switch (po->tp_version) { 3816 case TPACKET_V1: 3817 po->tp_hdrlen = TPACKET_HDRLEN; 3818 break; 3819 case TPACKET_V2: 3820 po->tp_hdrlen = TPACKET2_HDRLEN; 3821 break; 3822 case TPACKET_V3: 3823 po->tp_hdrlen = TPACKET3_HDRLEN; 3824 break; 3825 } 3826 3827 err = -EINVAL; 3828 if (unlikely((int)req->tp_block_size <= 0)) 3829 goto out; 3830 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1))) 3831 goto out; 3832 if (po->tp_version >= TPACKET_V3 && 3833 (int)(req->tp_block_size - 3834 BLK_PLUS_PRIV(req_u->req3.tp_sizeof_priv)) <= 0) 3835 goto out; 3836 if (unlikely(req->tp_frame_size < po->tp_hdrlen + 3837 po->tp_reserve)) 3838 goto out; 3839 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1))) 3840 goto out; 3841 3842 rb->frames_per_block = req->tp_block_size/req->tp_frame_size; 3843 if (unlikely(rb->frames_per_block <= 0)) 3844 goto out; 3845 if (unlikely((rb->frames_per_block * req->tp_block_nr) != 3846 req->tp_frame_nr)) 3847 goto out; 3848 3849 err = -ENOMEM; 3850 order = get_order(req->tp_block_size); 3851 pg_vec = alloc_pg_vec(req, order); 3852 if (unlikely(!pg_vec)) 3853 goto out; 3854 switch (po->tp_version) { 3855 case TPACKET_V3: 3856 /* Transmit path is not supported. We checked 3857 * it above but just being paranoid 3858 */ 3859 if (!tx_ring) 3860 init_prb_bdqc(po, rb, pg_vec, req_u, tx_ring); 3861 break; 3862 default: 3863 break; 3864 } 3865 } 3866 /* Done */ 3867 else { 3868 err = -EINVAL; 3869 if (unlikely(req->tp_frame_nr)) 3870 goto out; 3871 } 3872 3873 lock_sock(sk); 3874 3875 /* Detach socket from network */ 3876 spin_lock(&po->bind_lock); 3877 was_running = po->running; 3878 num = po->num; 3879 if (was_running) { 3880 po->num = 0; 3881 __unregister_prot_hook(sk, false); 3882 } 3883 spin_unlock(&po->bind_lock); 3884 3885 synchronize_net(); 3886 3887 err = -EBUSY; 3888 mutex_lock(&po->pg_vec_lock); 3889 if (closing || atomic_read(&po->mapped) == 0) { 3890 err = 0; 3891 spin_lock_bh(&rb_queue->lock); 3892 swap(rb->pg_vec, pg_vec); 3893 rb->frame_max = (req->tp_frame_nr - 1); 3894 rb->head = 0; 3895 rb->frame_size = req->tp_frame_size; 3896 spin_unlock_bh(&rb_queue->lock); 3897 3898 swap(rb->pg_vec_order, order); 3899 swap(rb->pg_vec_len, req->tp_block_nr); 3900 3901 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE; 3902 po->prot_hook.func = (po->rx_ring.pg_vec) ? 3903 tpacket_rcv : packet_rcv; 3904 skb_queue_purge(rb_queue); 3905 if (atomic_read(&po->mapped)) 3906 pr_err("packet_mmap: vma is busy: %d\n", 3907 atomic_read(&po->mapped)); 3908 } 3909 mutex_unlock(&po->pg_vec_lock); 3910 3911 spin_lock(&po->bind_lock); 3912 if (was_running) { 3913 po->num = num; 3914 register_prot_hook(sk); 3915 } 3916 spin_unlock(&po->bind_lock); 3917 if (closing && (po->tp_version > TPACKET_V2)) { 3918 /* Because we don't support block-based V3 on tx-ring */ 3919 if (!tx_ring) 3920 prb_shutdown_retire_blk_timer(po, tx_ring, rb_queue); 3921 } 3922 release_sock(sk); 3923 3924 if (pg_vec) 3925 free_pg_vec(pg_vec, order, req->tp_block_nr); 3926 out: 3927 return err; 3928 } 3929 3930 static int packet_mmap(struct file *file, struct socket *sock, 3931 struct vm_area_struct *vma) 3932 { 3933 struct sock *sk = sock->sk; 3934 struct packet_sock *po = pkt_sk(sk); 3935 unsigned long size, expected_size; 3936 struct packet_ring_buffer *rb; 3937 unsigned long start; 3938 int err = -EINVAL; 3939 int i; 3940 3941 if (vma->vm_pgoff) 3942 return -EINVAL; 3943 3944 mutex_lock(&po->pg_vec_lock); 3945 3946 expected_size = 0; 3947 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) { 3948 if (rb->pg_vec) { 3949 expected_size += rb->pg_vec_len 3950 * rb->pg_vec_pages 3951 * PAGE_SIZE; 3952 } 3953 } 3954 3955 if (expected_size == 0) 3956 goto out; 3957 3958 size = vma->vm_end - vma->vm_start; 3959 if (size != expected_size) 3960 goto out; 3961 3962 start = vma->vm_start; 3963 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) { 3964 if (rb->pg_vec == NULL) 3965 continue; 3966 3967 for (i = 0; i < rb->pg_vec_len; i++) { 3968 struct page *page; 3969 void *kaddr = rb->pg_vec[i].buffer; 3970 int pg_num; 3971 3972 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) { 3973 page = pgv_to_page(kaddr); 3974 err = vm_insert_page(vma, start, page); 3975 if (unlikely(err)) 3976 goto out; 3977 start += PAGE_SIZE; 3978 kaddr += PAGE_SIZE; 3979 } 3980 } 3981 } 3982 3983 atomic_inc(&po->mapped); 3984 vma->vm_ops = &packet_mmap_ops; 3985 err = 0; 3986 3987 out: 3988 mutex_unlock(&po->pg_vec_lock); 3989 return err; 3990 } 3991 3992 static const struct proto_ops packet_ops_spkt = { 3993 .family = PF_PACKET, 3994 .owner = THIS_MODULE, 3995 .release = packet_release, 3996 .bind = packet_bind_spkt, 3997 .connect = sock_no_connect, 3998 .socketpair = sock_no_socketpair, 3999 .accept = sock_no_accept, 4000 .getname = packet_getname_spkt, 4001 .poll = datagram_poll, 4002 .ioctl = packet_ioctl, 4003 .listen = sock_no_listen, 4004 .shutdown = sock_no_shutdown, 4005 .setsockopt = sock_no_setsockopt, 4006 .getsockopt = sock_no_getsockopt, 4007 .sendmsg = packet_sendmsg_spkt, 4008 .recvmsg = packet_recvmsg, 4009 .mmap = sock_no_mmap, 4010 .sendpage = sock_no_sendpage, 4011 }; 4012 4013 static const struct proto_ops packet_ops = { 4014 .family = PF_PACKET, 4015 .owner = THIS_MODULE, 4016 .release = packet_release, 4017 .bind = packet_bind, 4018 .connect = sock_no_connect, 4019 .socketpair = sock_no_socketpair, 4020 .accept = sock_no_accept, 4021 .getname = packet_getname, 4022 .poll = packet_poll, 4023 .ioctl = packet_ioctl, 4024 .listen = sock_no_listen, 4025 .shutdown = sock_no_shutdown, 4026 .setsockopt = packet_setsockopt, 4027 .getsockopt = packet_getsockopt, 4028 .sendmsg = packet_sendmsg, 4029 .recvmsg = packet_recvmsg, 4030 .mmap = packet_mmap, 4031 .sendpage = sock_no_sendpage, 4032 }; 4033 4034 static const struct net_proto_family packet_family_ops = { 4035 .family = PF_PACKET, 4036 .create = packet_create, 4037 .owner = THIS_MODULE, 4038 }; 4039 4040 static struct notifier_block packet_netdev_notifier = { 4041 .notifier_call = packet_notifier, 4042 }; 4043 4044 #ifdef CONFIG_PROC_FS 4045 4046 static void *packet_seq_start(struct seq_file *seq, loff_t *pos) 4047 __acquires(RCU) 4048 { 4049 struct net *net = seq_file_net(seq); 4050 4051 rcu_read_lock(); 4052 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos); 4053 } 4054 4055 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos) 4056 { 4057 struct net *net = seq_file_net(seq); 4058 return seq_hlist_next_rcu(v, &net->packet.sklist, pos); 4059 } 4060 4061 static void packet_seq_stop(struct seq_file *seq, void *v) 4062 __releases(RCU) 4063 { 4064 rcu_read_unlock(); 4065 } 4066 4067 static int packet_seq_show(struct seq_file *seq, void *v) 4068 { 4069 if (v == SEQ_START_TOKEN) 4070 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n"); 4071 else { 4072 struct sock *s = sk_entry(v); 4073 const struct packet_sock *po = pkt_sk(s); 4074 4075 seq_printf(seq, 4076 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n", 4077 s, 4078 atomic_read(&s->sk_refcnt), 4079 s->sk_type, 4080 ntohs(po->num), 4081 po->ifindex, 4082 po->running, 4083 atomic_read(&s->sk_rmem_alloc), 4084 from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)), 4085 sock_i_ino(s)); 4086 } 4087 4088 return 0; 4089 } 4090 4091 static const struct seq_operations packet_seq_ops = { 4092 .start = packet_seq_start, 4093 .next = packet_seq_next, 4094 .stop = packet_seq_stop, 4095 .show = packet_seq_show, 4096 }; 4097 4098 static int packet_seq_open(struct inode *inode, struct file *file) 4099 { 4100 return seq_open_net(inode, file, &packet_seq_ops, 4101 sizeof(struct seq_net_private)); 4102 } 4103 4104 static const struct file_operations packet_seq_fops = { 4105 .owner = THIS_MODULE, 4106 .open = packet_seq_open, 4107 .read = seq_read, 4108 .llseek = seq_lseek, 4109 .release = seq_release_net, 4110 }; 4111 4112 #endif 4113 4114 static int __net_init packet_net_init(struct net *net) 4115 { 4116 mutex_init(&net->packet.sklist_lock); 4117 INIT_HLIST_HEAD(&net->packet.sklist); 4118 4119 if (!proc_create("packet", 0, net->proc_net, &packet_seq_fops)) 4120 return -ENOMEM; 4121 4122 return 0; 4123 } 4124 4125 static void __net_exit packet_net_exit(struct net *net) 4126 { 4127 remove_proc_entry("packet", net->proc_net); 4128 } 4129 4130 static struct pernet_operations packet_net_ops = { 4131 .init = packet_net_init, 4132 .exit = packet_net_exit, 4133 }; 4134 4135 4136 static void __exit packet_exit(void) 4137 { 4138 unregister_netdevice_notifier(&packet_netdev_notifier); 4139 unregister_pernet_subsys(&packet_net_ops); 4140 sock_unregister(PF_PACKET); 4141 proto_unregister(&packet_proto); 4142 } 4143 4144 static int __init packet_init(void) 4145 { 4146 int rc = proto_register(&packet_proto, 0); 4147 4148 if (rc != 0) 4149 goto out; 4150 4151 sock_register(&packet_family_ops); 4152 register_pernet_subsys(&packet_net_ops); 4153 register_netdevice_notifier(&packet_netdev_notifier); 4154 out: 4155 return rc; 4156 } 4157 4158 module_init(packet_init); 4159 module_exit(packet_exit); 4160 MODULE_LICENSE("GPL"); 4161 MODULE_ALIAS_NETPROTO(PF_PACKET); 4162