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 union { 220 struct sockaddr_pkt pkt; 221 union { 222 /* Trick: alias skb original length with 223 * ll.sll_family and ll.protocol in order 224 * to save room. 225 */ 226 unsigned int origlen; 227 struct sockaddr_ll ll; 228 }; 229 } sa; 230 }; 231 232 #define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb)) 233 234 #define GET_PBDQC_FROM_RB(x) ((struct tpacket_kbdq_core *)(&(x)->prb_bdqc)) 235 #define GET_PBLOCK_DESC(x, bid) \ 236 ((struct tpacket_block_desc *)((x)->pkbdq[(bid)].buffer)) 237 #define GET_CURR_PBLOCK_DESC_FROM_CORE(x) \ 238 ((struct tpacket_block_desc *)((x)->pkbdq[(x)->kactive_blk_num].buffer)) 239 #define GET_NEXT_PRB_BLK_NUM(x) \ 240 (((x)->kactive_blk_num < ((x)->knum_blocks-1)) ? \ 241 ((x)->kactive_blk_num+1) : 0) 242 243 static void __fanout_unlink(struct sock *sk, struct packet_sock *po); 244 static void __fanout_link(struct sock *sk, struct packet_sock *po); 245 246 static int packet_direct_xmit(struct sk_buff *skb) 247 { 248 struct net_device *dev = skb->dev; 249 netdev_features_t features; 250 struct netdev_queue *txq; 251 int ret = NETDEV_TX_BUSY; 252 253 if (unlikely(!netif_running(dev) || 254 !netif_carrier_ok(dev))) 255 goto drop; 256 257 features = netif_skb_features(skb); 258 if (skb_needs_linearize(skb, features) && 259 __skb_linearize(skb)) 260 goto drop; 261 262 txq = skb_get_tx_queue(dev, skb); 263 264 local_bh_disable(); 265 266 HARD_TX_LOCK(dev, txq, smp_processor_id()); 267 if (!netif_xmit_frozen_or_drv_stopped(txq)) 268 ret = netdev_start_xmit(skb, dev, txq, false); 269 HARD_TX_UNLOCK(dev, txq); 270 271 local_bh_enable(); 272 273 if (!dev_xmit_complete(ret)) 274 kfree_skb(skb); 275 276 return ret; 277 drop: 278 atomic_long_inc(&dev->tx_dropped); 279 kfree_skb(skb); 280 return NET_XMIT_DROP; 281 } 282 283 static struct net_device *packet_cached_dev_get(struct packet_sock *po) 284 { 285 struct net_device *dev; 286 287 rcu_read_lock(); 288 dev = rcu_dereference(po->cached_dev); 289 if (likely(dev)) 290 dev_hold(dev); 291 rcu_read_unlock(); 292 293 return dev; 294 } 295 296 static void packet_cached_dev_assign(struct packet_sock *po, 297 struct net_device *dev) 298 { 299 rcu_assign_pointer(po->cached_dev, dev); 300 } 301 302 static void packet_cached_dev_reset(struct packet_sock *po) 303 { 304 RCU_INIT_POINTER(po->cached_dev, NULL); 305 } 306 307 static bool packet_use_direct_xmit(const struct packet_sock *po) 308 { 309 return po->xmit == packet_direct_xmit; 310 } 311 312 static u16 __packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb) 313 { 314 return (u16) raw_smp_processor_id() % dev->real_num_tx_queues; 315 } 316 317 static void packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb) 318 { 319 const struct net_device_ops *ops = dev->netdev_ops; 320 u16 queue_index; 321 322 if (ops->ndo_select_queue) { 323 queue_index = ops->ndo_select_queue(dev, skb, NULL, 324 __packet_pick_tx_queue); 325 queue_index = netdev_cap_txqueue(dev, queue_index); 326 } else { 327 queue_index = __packet_pick_tx_queue(dev, skb); 328 } 329 330 skb_set_queue_mapping(skb, queue_index); 331 } 332 333 /* register_prot_hook must be invoked with the po->bind_lock held, 334 * or from a context in which asynchronous accesses to the packet 335 * socket is not possible (packet_create()). 336 */ 337 static void register_prot_hook(struct sock *sk) 338 { 339 struct packet_sock *po = pkt_sk(sk); 340 341 if (!po->running) { 342 if (po->fanout) 343 __fanout_link(sk, po); 344 else 345 dev_add_pack(&po->prot_hook); 346 347 sock_hold(sk); 348 po->running = 1; 349 } 350 } 351 352 /* {,__}unregister_prot_hook() must be invoked with the po->bind_lock 353 * held. If the sync parameter is true, we will temporarily drop 354 * the po->bind_lock and do a synchronize_net to make sure no 355 * asynchronous packet processing paths still refer to the elements 356 * of po->prot_hook. If the sync parameter is false, it is the 357 * callers responsibility to take care of this. 358 */ 359 static void __unregister_prot_hook(struct sock *sk, bool sync) 360 { 361 struct packet_sock *po = pkt_sk(sk); 362 363 po->running = 0; 364 365 if (po->fanout) 366 __fanout_unlink(sk, po); 367 else 368 __dev_remove_pack(&po->prot_hook); 369 370 __sock_put(sk); 371 372 if (sync) { 373 spin_unlock(&po->bind_lock); 374 synchronize_net(); 375 spin_lock(&po->bind_lock); 376 } 377 } 378 379 static void unregister_prot_hook(struct sock *sk, bool sync) 380 { 381 struct packet_sock *po = pkt_sk(sk); 382 383 if (po->running) 384 __unregister_prot_hook(sk, sync); 385 } 386 387 static inline struct page * __pure pgv_to_page(void *addr) 388 { 389 if (is_vmalloc_addr(addr)) 390 return vmalloc_to_page(addr); 391 return virt_to_page(addr); 392 } 393 394 static void __packet_set_status(struct packet_sock *po, void *frame, int status) 395 { 396 union tpacket_uhdr h; 397 398 h.raw = frame; 399 switch (po->tp_version) { 400 case TPACKET_V1: 401 h.h1->tp_status = status; 402 flush_dcache_page(pgv_to_page(&h.h1->tp_status)); 403 break; 404 case TPACKET_V2: 405 h.h2->tp_status = status; 406 flush_dcache_page(pgv_to_page(&h.h2->tp_status)); 407 break; 408 case TPACKET_V3: 409 default: 410 WARN(1, "TPACKET version not supported.\n"); 411 BUG(); 412 } 413 414 smp_wmb(); 415 } 416 417 static int __packet_get_status(struct packet_sock *po, void *frame) 418 { 419 union tpacket_uhdr h; 420 421 smp_rmb(); 422 423 h.raw = frame; 424 switch (po->tp_version) { 425 case TPACKET_V1: 426 flush_dcache_page(pgv_to_page(&h.h1->tp_status)); 427 return h.h1->tp_status; 428 case TPACKET_V2: 429 flush_dcache_page(pgv_to_page(&h.h2->tp_status)); 430 return h.h2->tp_status; 431 case TPACKET_V3: 432 default: 433 WARN(1, "TPACKET version not supported.\n"); 434 BUG(); 435 return 0; 436 } 437 } 438 439 static __u32 tpacket_get_timestamp(struct sk_buff *skb, struct timespec *ts, 440 unsigned int flags) 441 { 442 struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb); 443 444 if (shhwtstamps && 445 (flags & SOF_TIMESTAMPING_RAW_HARDWARE) && 446 ktime_to_timespec_cond(shhwtstamps->hwtstamp, ts)) 447 return TP_STATUS_TS_RAW_HARDWARE; 448 449 if (ktime_to_timespec_cond(skb->tstamp, ts)) 450 return TP_STATUS_TS_SOFTWARE; 451 452 return 0; 453 } 454 455 static __u32 __packet_set_timestamp(struct packet_sock *po, void *frame, 456 struct sk_buff *skb) 457 { 458 union tpacket_uhdr h; 459 struct timespec ts; 460 __u32 ts_status; 461 462 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp))) 463 return 0; 464 465 h.raw = frame; 466 switch (po->tp_version) { 467 case TPACKET_V1: 468 h.h1->tp_sec = ts.tv_sec; 469 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC; 470 break; 471 case TPACKET_V2: 472 h.h2->tp_sec = ts.tv_sec; 473 h.h2->tp_nsec = ts.tv_nsec; 474 break; 475 case TPACKET_V3: 476 default: 477 WARN(1, "TPACKET version not supported.\n"); 478 BUG(); 479 } 480 481 /* one flush is safe, as both fields always lie on the same cacheline */ 482 flush_dcache_page(pgv_to_page(&h.h1->tp_sec)); 483 smp_wmb(); 484 485 return ts_status; 486 } 487 488 static void *packet_lookup_frame(struct packet_sock *po, 489 struct packet_ring_buffer *rb, 490 unsigned int position, 491 int status) 492 { 493 unsigned int pg_vec_pos, frame_offset; 494 union tpacket_uhdr h; 495 496 pg_vec_pos = position / rb->frames_per_block; 497 frame_offset = position % rb->frames_per_block; 498 499 h.raw = rb->pg_vec[pg_vec_pos].buffer + 500 (frame_offset * rb->frame_size); 501 502 if (status != __packet_get_status(po, h.raw)) 503 return NULL; 504 505 return h.raw; 506 } 507 508 static void *packet_current_frame(struct packet_sock *po, 509 struct packet_ring_buffer *rb, 510 int status) 511 { 512 return packet_lookup_frame(po, rb, rb->head, status); 513 } 514 515 static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc) 516 { 517 del_timer_sync(&pkc->retire_blk_timer); 518 } 519 520 static void prb_shutdown_retire_blk_timer(struct packet_sock *po, 521 int tx_ring, 522 struct sk_buff_head *rb_queue) 523 { 524 struct tpacket_kbdq_core *pkc; 525 526 pkc = tx_ring ? GET_PBDQC_FROM_RB(&po->tx_ring) : 527 GET_PBDQC_FROM_RB(&po->rx_ring); 528 529 spin_lock_bh(&rb_queue->lock); 530 pkc->delete_blk_timer = 1; 531 spin_unlock_bh(&rb_queue->lock); 532 533 prb_del_retire_blk_timer(pkc); 534 } 535 536 static void prb_init_blk_timer(struct packet_sock *po, 537 struct tpacket_kbdq_core *pkc, 538 void (*func) (unsigned long)) 539 { 540 init_timer(&pkc->retire_blk_timer); 541 pkc->retire_blk_timer.data = (long)po; 542 pkc->retire_blk_timer.function = func; 543 pkc->retire_blk_timer.expires = jiffies; 544 } 545 546 static void prb_setup_retire_blk_timer(struct packet_sock *po, int tx_ring) 547 { 548 struct tpacket_kbdq_core *pkc; 549 550 if (tx_ring) 551 BUG(); 552 553 pkc = tx_ring ? GET_PBDQC_FROM_RB(&po->tx_ring) : 554 GET_PBDQC_FROM_RB(&po->rx_ring); 555 prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired); 556 } 557 558 static int prb_calc_retire_blk_tmo(struct packet_sock *po, 559 int blk_size_in_bytes) 560 { 561 struct net_device *dev; 562 unsigned int mbits = 0, msec = 0, div = 0, tmo = 0; 563 struct ethtool_cmd ecmd; 564 int err; 565 u32 speed; 566 567 rtnl_lock(); 568 dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex); 569 if (unlikely(!dev)) { 570 rtnl_unlock(); 571 return DEFAULT_PRB_RETIRE_TOV; 572 } 573 err = __ethtool_get_settings(dev, &ecmd); 574 speed = ethtool_cmd_speed(&ecmd); 575 rtnl_unlock(); 576 if (!err) { 577 /* 578 * If the link speed is so slow you don't really 579 * need to worry about perf anyways 580 */ 581 if (speed < SPEED_1000 || speed == SPEED_UNKNOWN) { 582 return DEFAULT_PRB_RETIRE_TOV; 583 } else { 584 msec = 1; 585 div = speed / 1000; 586 } 587 } 588 589 mbits = (blk_size_in_bytes * 8) / (1024 * 1024); 590 591 if (div) 592 mbits /= div; 593 594 tmo = mbits * msec; 595 596 if (div) 597 return tmo+1; 598 return tmo; 599 } 600 601 static void prb_init_ft_ops(struct tpacket_kbdq_core *p1, 602 union tpacket_req_u *req_u) 603 { 604 p1->feature_req_word = req_u->req3.tp_feature_req_word; 605 } 606 607 static void init_prb_bdqc(struct packet_sock *po, 608 struct packet_ring_buffer *rb, 609 struct pgv *pg_vec, 610 union tpacket_req_u *req_u, int tx_ring) 611 { 612 struct tpacket_kbdq_core *p1 = GET_PBDQC_FROM_RB(rb); 613 struct tpacket_block_desc *pbd; 614 615 memset(p1, 0x0, sizeof(*p1)); 616 617 p1->knxt_seq_num = 1; 618 p1->pkbdq = pg_vec; 619 pbd = (struct tpacket_block_desc *)pg_vec[0].buffer; 620 p1->pkblk_start = pg_vec[0].buffer; 621 p1->kblk_size = req_u->req3.tp_block_size; 622 p1->knum_blocks = req_u->req3.tp_block_nr; 623 p1->hdrlen = po->tp_hdrlen; 624 p1->version = po->tp_version; 625 p1->last_kactive_blk_num = 0; 626 po->stats.stats3.tp_freeze_q_cnt = 0; 627 if (req_u->req3.tp_retire_blk_tov) 628 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov; 629 else 630 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po, 631 req_u->req3.tp_block_size); 632 p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov); 633 p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv; 634 635 p1->max_frame_len = p1->kblk_size - BLK_PLUS_PRIV(p1->blk_sizeof_priv); 636 prb_init_ft_ops(p1, req_u); 637 prb_setup_retire_blk_timer(po, tx_ring); 638 prb_open_block(p1, pbd); 639 } 640 641 /* Do NOT update the last_blk_num first. 642 * Assumes sk_buff_head lock is held. 643 */ 644 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc) 645 { 646 mod_timer(&pkc->retire_blk_timer, 647 jiffies + pkc->tov_in_jiffies); 648 pkc->last_kactive_blk_num = pkc->kactive_blk_num; 649 } 650 651 /* 652 * Timer logic: 653 * 1) We refresh the timer only when we open a block. 654 * By doing this we don't waste cycles refreshing the timer 655 * on packet-by-packet basis. 656 * 657 * With a 1MB block-size, on a 1Gbps line, it will take 658 * i) ~8 ms to fill a block + ii) memcpy etc. 659 * In this cut we are not accounting for the memcpy time. 660 * 661 * So, if the user sets the 'tmo' to 10ms then the timer 662 * will never fire while the block is still getting filled 663 * (which is what we want). However, the user could choose 664 * to close a block early and that's fine. 665 * 666 * But when the timer does fire, we check whether or not to refresh it. 667 * Since the tmo granularity is in msecs, it is not too expensive 668 * to refresh the timer, lets say every '8' msecs. 669 * Either the user can set the 'tmo' or we can derive it based on 670 * a) line-speed and b) block-size. 671 * prb_calc_retire_blk_tmo() calculates the tmo. 672 * 673 */ 674 static void prb_retire_rx_blk_timer_expired(unsigned long data) 675 { 676 struct packet_sock *po = (struct packet_sock *)data; 677 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(&po->rx_ring); 678 unsigned int frozen; 679 struct tpacket_block_desc *pbd; 680 681 spin_lock(&po->sk.sk_receive_queue.lock); 682 683 frozen = prb_queue_frozen(pkc); 684 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc); 685 686 if (unlikely(pkc->delete_blk_timer)) 687 goto out; 688 689 /* We only need to plug the race when the block is partially filled. 690 * tpacket_rcv: 691 * lock(); increment BLOCK_NUM_PKTS; unlock() 692 * copy_bits() is in progress ... 693 * timer fires on other cpu: 694 * we can't retire the current block because copy_bits 695 * is in progress. 696 * 697 */ 698 if (BLOCK_NUM_PKTS(pbd)) { 699 while (atomic_read(&pkc->blk_fill_in_prog)) { 700 /* Waiting for skb_copy_bits to finish... */ 701 cpu_relax(); 702 } 703 } 704 705 if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) { 706 if (!frozen) { 707 if (!BLOCK_NUM_PKTS(pbd)) { 708 /* An empty block. Just refresh the timer. */ 709 goto refresh_timer; 710 } 711 prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO); 712 if (!prb_dispatch_next_block(pkc, po)) 713 goto refresh_timer; 714 else 715 goto out; 716 } else { 717 /* Case 1. Queue was frozen because user-space was 718 * lagging behind. 719 */ 720 if (prb_curr_blk_in_use(pkc, pbd)) { 721 /* 722 * Ok, user-space is still behind. 723 * So just refresh the timer. 724 */ 725 goto refresh_timer; 726 } else { 727 /* Case 2. queue was frozen,user-space caught up, 728 * now the link went idle && the timer fired. 729 * We don't have a block to close.So we open this 730 * block and restart the timer. 731 * opening a block thaws the queue,restarts timer 732 * Thawing/timer-refresh is a side effect. 733 */ 734 prb_open_block(pkc, pbd); 735 goto out; 736 } 737 } 738 } 739 740 refresh_timer: 741 _prb_refresh_rx_retire_blk_timer(pkc); 742 743 out: 744 spin_unlock(&po->sk.sk_receive_queue.lock); 745 } 746 747 static void prb_flush_block(struct tpacket_kbdq_core *pkc1, 748 struct tpacket_block_desc *pbd1, __u32 status) 749 { 750 /* Flush everything minus the block header */ 751 752 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1 753 u8 *start, *end; 754 755 start = (u8 *)pbd1; 756 757 /* Skip the block header(we know header WILL fit in 4K) */ 758 start += PAGE_SIZE; 759 760 end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end); 761 for (; start < end; start += PAGE_SIZE) 762 flush_dcache_page(pgv_to_page(start)); 763 764 smp_wmb(); 765 #endif 766 767 /* Now update the block status. */ 768 769 BLOCK_STATUS(pbd1) = status; 770 771 /* Flush the block header */ 772 773 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1 774 start = (u8 *)pbd1; 775 flush_dcache_page(pgv_to_page(start)); 776 777 smp_wmb(); 778 #endif 779 } 780 781 /* 782 * Side effect: 783 * 784 * 1) flush the block 785 * 2) Increment active_blk_num 786 * 787 * Note:We DONT refresh the timer on purpose. 788 * Because almost always the next block will be opened. 789 */ 790 static void prb_close_block(struct tpacket_kbdq_core *pkc1, 791 struct tpacket_block_desc *pbd1, 792 struct packet_sock *po, unsigned int stat) 793 { 794 __u32 status = TP_STATUS_USER | stat; 795 796 struct tpacket3_hdr *last_pkt; 797 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1; 798 struct sock *sk = &po->sk; 799 800 if (po->stats.stats3.tp_drops) 801 status |= TP_STATUS_LOSING; 802 803 last_pkt = (struct tpacket3_hdr *)pkc1->prev; 804 last_pkt->tp_next_offset = 0; 805 806 /* Get the ts of the last pkt */ 807 if (BLOCK_NUM_PKTS(pbd1)) { 808 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec; 809 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec; 810 } else { 811 /* Ok, we tmo'd - so get the current time. 812 * 813 * It shouldn't really happen as we don't close empty 814 * blocks. See prb_retire_rx_blk_timer_expired(). 815 */ 816 struct timespec ts; 817 getnstimeofday(&ts); 818 h1->ts_last_pkt.ts_sec = ts.tv_sec; 819 h1->ts_last_pkt.ts_nsec = ts.tv_nsec; 820 } 821 822 smp_wmb(); 823 824 /* Flush the block */ 825 prb_flush_block(pkc1, pbd1, status); 826 827 sk->sk_data_ready(sk); 828 829 pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1); 830 } 831 832 static void prb_thaw_queue(struct tpacket_kbdq_core *pkc) 833 { 834 pkc->reset_pending_on_curr_blk = 0; 835 } 836 837 /* 838 * Side effect of opening a block: 839 * 840 * 1) prb_queue is thawed. 841 * 2) retire_blk_timer is refreshed. 842 * 843 */ 844 static void prb_open_block(struct tpacket_kbdq_core *pkc1, 845 struct tpacket_block_desc *pbd1) 846 { 847 struct timespec ts; 848 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1; 849 850 smp_rmb(); 851 852 /* We could have just memset this but we will lose the 853 * flexibility of making the priv area sticky 854 */ 855 856 BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++; 857 BLOCK_NUM_PKTS(pbd1) = 0; 858 BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv); 859 860 getnstimeofday(&ts); 861 862 h1->ts_first_pkt.ts_sec = ts.tv_sec; 863 h1->ts_first_pkt.ts_nsec = ts.tv_nsec; 864 865 pkc1->pkblk_start = (char *)pbd1; 866 pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv); 867 868 BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv); 869 BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN; 870 871 pbd1->version = pkc1->version; 872 pkc1->prev = pkc1->nxt_offset; 873 pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size; 874 875 prb_thaw_queue(pkc1); 876 _prb_refresh_rx_retire_blk_timer(pkc1); 877 878 smp_wmb(); 879 } 880 881 /* 882 * Queue freeze logic: 883 * 1) Assume tp_block_nr = 8 blocks. 884 * 2) At time 't0', user opens Rx ring. 885 * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7 886 * 4) user-space is either sleeping or processing block '0'. 887 * 5) tpacket_rcv is currently filling block '7', since there is no space left, 888 * it will close block-7,loop around and try to fill block '0'. 889 * call-flow: 890 * __packet_lookup_frame_in_block 891 * prb_retire_current_block() 892 * prb_dispatch_next_block() 893 * |->(BLOCK_STATUS == USER) evaluates to true 894 * 5.1) Since block-0 is currently in-use, we just freeze the queue. 895 * 6) Now there are two cases: 896 * 6.1) Link goes idle right after the queue is frozen. 897 * But remember, the last open_block() refreshed the timer. 898 * When this timer expires,it will refresh itself so that we can 899 * re-open block-0 in near future. 900 * 6.2) Link is busy and keeps on receiving packets. This is a simple 901 * case and __packet_lookup_frame_in_block will check if block-0 902 * is free and can now be re-used. 903 */ 904 static void prb_freeze_queue(struct tpacket_kbdq_core *pkc, 905 struct packet_sock *po) 906 { 907 pkc->reset_pending_on_curr_blk = 1; 908 po->stats.stats3.tp_freeze_q_cnt++; 909 } 910 911 #define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT)) 912 913 /* 914 * If the next block is free then we will dispatch it 915 * and return a good offset. 916 * Else, we will freeze the queue. 917 * So, caller must check the return value. 918 */ 919 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc, 920 struct packet_sock *po) 921 { 922 struct tpacket_block_desc *pbd; 923 924 smp_rmb(); 925 926 /* 1. Get current block num */ 927 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc); 928 929 /* 2. If this block is currently in_use then freeze the queue */ 930 if (TP_STATUS_USER & BLOCK_STATUS(pbd)) { 931 prb_freeze_queue(pkc, po); 932 return NULL; 933 } 934 935 /* 936 * 3. 937 * open this block and return the offset where the first packet 938 * needs to get stored. 939 */ 940 prb_open_block(pkc, pbd); 941 return (void *)pkc->nxt_offset; 942 } 943 944 static void prb_retire_current_block(struct tpacket_kbdq_core *pkc, 945 struct packet_sock *po, unsigned int status) 946 { 947 struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc); 948 949 /* retire/close the current block */ 950 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) { 951 /* 952 * Plug the case where copy_bits() is in progress on 953 * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't 954 * have space to copy the pkt in the current block and 955 * called prb_retire_current_block() 956 * 957 * We don't need to worry about the TMO case because 958 * the timer-handler already handled this case. 959 */ 960 if (!(status & TP_STATUS_BLK_TMO)) { 961 while (atomic_read(&pkc->blk_fill_in_prog)) { 962 /* Waiting for skb_copy_bits to finish... */ 963 cpu_relax(); 964 } 965 } 966 prb_close_block(pkc, pbd, po, status); 967 return; 968 } 969 } 970 971 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc, 972 struct tpacket_block_desc *pbd) 973 { 974 return TP_STATUS_USER & BLOCK_STATUS(pbd); 975 } 976 977 static int prb_queue_frozen(struct tpacket_kbdq_core *pkc) 978 { 979 return pkc->reset_pending_on_curr_blk; 980 } 981 982 static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb) 983 { 984 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb); 985 atomic_dec(&pkc->blk_fill_in_prog); 986 } 987 988 static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc, 989 struct tpacket3_hdr *ppd) 990 { 991 ppd->hv1.tp_rxhash = skb_get_hash(pkc->skb); 992 } 993 994 static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc, 995 struct tpacket3_hdr *ppd) 996 { 997 ppd->hv1.tp_rxhash = 0; 998 } 999 1000 static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc, 1001 struct tpacket3_hdr *ppd) 1002 { 1003 if (skb_vlan_tag_present(pkc->skb)) { 1004 ppd->hv1.tp_vlan_tci = skb_vlan_tag_get(pkc->skb); 1005 ppd->hv1.tp_vlan_tpid = ntohs(pkc->skb->vlan_proto); 1006 ppd->tp_status = TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID; 1007 } else { 1008 ppd->hv1.tp_vlan_tci = 0; 1009 ppd->hv1.tp_vlan_tpid = 0; 1010 ppd->tp_status = TP_STATUS_AVAILABLE; 1011 } 1012 } 1013 1014 static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc, 1015 struct tpacket3_hdr *ppd) 1016 { 1017 ppd->hv1.tp_padding = 0; 1018 prb_fill_vlan_info(pkc, ppd); 1019 1020 if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH) 1021 prb_fill_rxhash(pkc, ppd); 1022 else 1023 prb_clear_rxhash(pkc, ppd); 1024 } 1025 1026 static void prb_fill_curr_block(char *curr, 1027 struct tpacket_kbdq_core *pkc, 1028 struct tpacket_block_desc *pbd, 1029 unsigned int len) 1030 { 1031 struct tpacket3_hdr *ppd; 1032 1033 ppd = (struct tpacket3_hdr *)curr; 1034 ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len); 1035 pkc->prev = curr; 1036 pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len); 1037 BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len); 1038 BLOCK_NUM_PKTS(pbd) += 1; 1039 atomic_inc(&pkc->blk_fill_in_prog); 1040 prb_run_all_ft_ops(pkc, ppd); 1041 } 1042 1043 /* Assumes caller has the sk->rx_queue.lock */ 1044 static void *__packet_lookup_frame_in_block(struct packet_sock *po, 1045 struct sk_buff *skb, 1046 int status, 1047 unsigned int len 1048 ) 1049 { 1050 struct tpacket_kbdq_core *pkc; 1051 struct tpacket_block_desc *pbd; 1052 char *curr, *end; 1053 1054 pkc = GET_PBDQC_FROM_RB(&po->rx_ring); 1055 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc); 1056 1057 /* Queue is frozen when user space is lagging behind */ 1058 if (prb_queue_frozen(pkc)) { 1059 /* 1060 * Check if that last block which caused the queue to freeze, 1061 * is still in_use by user-space. 1062 */ 1063 if (prb_curr_blk_in_use(pkc, pbd)) { 1064 /* Can't record this packet */ 1065 return NULL; 1066 } else { 1067 /* 1068 * Ok, the block was released by user-space. 1069 * Now let's open that block. 1070 * opening a block also thaws the queue. 1071 * Thawing is a side effect. 1072 */ 1073 prb_open_block(pkc, pbd); 1074 } 1075 } 1076 1077 smp_mb(); 1078 curr = pkc->nxt_offset; 1079 pkc->skb = skb; 1080 end = (char *)pbd + pkc->kblk_size; 1081 1082 /* first try the current block */ 1083 if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) { 1084 prb_fill_curr_block(curr, pkc, pbd, len); 1085 return (void *)curr; 1086 } 1087 1088 /* Ok, close the current block */ 1089 prb_retire_current_block(pkc, po, 0); 1090 1091 /* Now, try to dispatch the next block */ 1092 curr = (char *)prb_dispatch_next_block(pkc, po); 1093 if (curr) { 1094 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc); 1095 prb_fill_curr_block(curr, pkc, pbd, len); 1096 return (void *)curr; 1097 } 1098 1099 /* 1100 * No free blocks are available.user_space hasn't caught up yet. 1101 * Queue was just frozen and now this packet will get dropped. 1102 */ 1103 return NULL; 1104 } 1105 1106 static void *packet_current_rx_frame(struct packet_sock *po, 1107 struct sk_buff *skb, 1108 int status, unsigned int len) 1109 { 1110 char *curr = NULL; 1111 switch (po->tp_version) { 1112 case TPACKET_V1: 1113 case TPACKET_V2: 1114 curr = packet_lookup_frame(po, &po->rx_ring, 1115 po->rx_ring.head, status); 1116 return curr; 1117 case TPACKET_V3: 1118 return __packet_lookup_frame_in_block(po, skb, status, len); 1119 default: 1120 WARN(1, "TPACKET version not supported\n"); 1121 BUG(); 1122 return NULL; 1123 } 1124 } 1125 1126 static void *prb_lookup_block(struct packet_sock *po, 1127 struct packet_ring_buffer *rb, 1128 unsigned int idx, 1129 int status) 1130 { 1131 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb); 1132 struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, idx); 1133 1134 if (status != BLOCK_STATUS(pbd)) 1135 return NULL; 1136 return pbd; 1137 } 1138 1139 static int prb_previous_blk_num(struct packet_ring_buffer *rb) 1140 { 1141 unsigned int prev; 1142 if (rb->prb_bdqc.kactive_blk_num) 1143 prev = rb->prb_bdqc.kactive_blk_num-1; 1144 else 1145 prev = rb->prb_bdqc.knum_blocks-1; 1146 return prev; 1147 } 1148 1149 /* Assumes caller has held the rx_queue.lock */ 1150 static void *__prb_previous_block(struct packet_sock *po, 1151 struct packet_ring_buffer *rb, 1152 int status) 1153 { 1154 unsigned int previous = prb_previous_blk_num(rb); 1155 return prb_lookup_block(po, rb, previous, status); 1156 } 1157 1158 static void *packet_previous_rx_frame(struct packet_sock *po, 1159 struct packet_ring_buffer *rb, 1160 int status) 1161 { 1162 if (po->tp_version <= TPACKET_V2) 1163 return packet_previous_frame(po, rb, status); 1164 1165 return __prb_previous_block(po, rb, status); 1166 } 1167 1168 static void packet_increment_rx_head(struct packet_sock *po, 1169 struct packet_ring_buffer *rb) 1170 { 1171 switch (po->tp_version) { 1172 case TPACKET_V1: 1173 case TPACKET_V2: 1174 return packet_increment_head(rb); 1175 case TPACKET_V3: 1176 default: 1177 WARN(1, "TPACKET version not supported.\n"); 1178 BUG(); 1179 return; 1180 } 1181 } 1182 1183 static void *packet_previous_frame(struct packet_sock *po, 1184 struct packet_ring_buffer *rb, 1185 int status) 1186 { 1187 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max; 1188 return packet_lookup_frame(po, rb, previous, status); 1189 } 1190 1191 static void packet_increment_head(struct packet_ring_buffer *buff) 1192 { 1193 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0; 1194 } 1195 1196 static void packet_inc_pending(struct packet_ring_buffer *rb) 1197 { 1198 this_cpu_inc(*rb->pending_refcnt); 1199 } 1200 1201 static void packet_dec_pending(struct packet_ring_buffer *rb) 1202 { 1203 this_cpu_dec(*rb->pending_refcnt); 1204 } 1205 1206 static unsigned int packet_read_pending(const struct packet_ring_buffer *rb) 1207 { 1208 unsigned int refcnt = 0; 1209 int cpu; 1210 1211 /* We don't use pending refcount in rx_ring. */ 1212 if (rb->pending_refcnt == NULL) 1213 return 0; 1214 1215 for_each_possible_cpu(cpu) 1216 refcnt += *per_cpu_ptr(rb->pending_refcnt, cpu); 1217 1218 return refcnt; 1219 } 1220 1221 static int packet_alloc_pending(struct packet_sock *po) 1222 { 1223 po->rx_ring.pending_refcnt = NULL; 1224 1225 po->tx_ring.pending_refcnt = alloc_percpu(unsigned int); 1226 if (unlikely(po->tx_ring.pending_refcnt == NULL)) 1227 return -ENOBUFS; 1228 1229 return 0; 1230 } 1231 1232 static void packet_free_pending(struct packet_sock *po) 1233 { 1234 free_percpu(po->tx_ring.pending_refcnt); 1235 } 1236 1237 static bool packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb) 1238 { 1239 struct sock *sk = &po->sk; 1240 bool has_room; 1241 1242 if (po->prot_hook.func != tpacket_rcv) 1243 return (atomic_read(&sk->sk_rmem_alloc) + skb->truesize) 1244 <= sk->sk_rcvbuf; 1245 1246 spin_lock(&sk->sk_receive_queue.lock); 1247 if (po->tp_version == TPACKET_V3) 1248 has_room = prb_lookup_block(po, &po->rx_ring, 1249 po->rx_ring.prb_bdqc.kactive_blk_num, 1250 TP_STATUS_KERNEL); 1251 else 1252 has_room = packet_lookup_frame(po, &po->rx_ring, 1253 po->rx_ring.head, 1254 TP_STATUS_KERNEL); 1255 spin_unlock(&sk->sk_receive_queue.lock); 1256 1257 return has_room; 1258 } 1259 1260 static void packet_sock_destruct(struct sock *sk) 1261 { 1262 skb_queue_purge(&sk->sk_error_queue); 1263 1264 WARN_ON(atomic_read(&sk->sk_rmem_alloc)); 1265 WARN_ON(atomic_read(&sk->sk_wmem_alloc)); 1266 1267 if (!sock_flag(sk, SOCK_DEAD)) { 1268 pr_err("Attempt to release alive packet socket: %p\n", sk); 1269 return; 1270 } 1271 1272 sk_refcnt_debug_dec(sk); 1273 } 1274 1275 static int fanout_rr_next(struct packet_fanout *f, unsigned int num) 1276 { 1277 int x = atomic_read(&f->rr_cur) + 1; 1278 1279 if (x >= num) 1280 x = 0; 1281 1282 return x; 1283 } 1284 1285 static unsigned int fanout_demux_hash(struct packet_fanout *f, 1286 struct sk_buff *skb, 1287 unsigned int num) 1288 { 1289 return reciprocal_scale(skb_get_hash(skb), num); 1290 } 1291 1292 static unsigned int fanout_demux_lb(struct packet_fanout *f, 1293 struct sk_buff *skb, 1294 unsigned int num) 1295 { 1296 int cur, old; 1297 1298 cur = atomic_read(&f->rr_cur); 1299 while ((old = atomic_cmpxchg(&f->rr_cur, cur, 1300 fanout_rr_next(f, num))) != cur) 1301 cur = old; 1302 return cur; 1303 } 1304 1305 static unsigned int fanout_demux_cpu(struct packet_fanout *f, 1306 struct sk_buff *skb, 1307 unsigned int num) 1308 { 1309 return smp_processor_id() % num; 1310 } 1311 1312 static unsigned int fanout_demux_rnd(struct packet_fanout *f, 1313 struct sk_buff *skb, 1314 unsigned int num) 1315 { 1316 return prandom_u32_max(num); 1317 } 1318 1319 static unsigned int fanout_demux_rollover(struct packet_fanout *f, 1320 struct sk_buff *skb, 1321 unsigned int idx, unsigned int skip, 1322 unsigned int num) 1323 { 1324 unsigned int i, j; 1325 1326 i = j = min_t(int, f->next[idx], num - 1); 1327 do { 1328 if (i != skip && packet_rcv_has_room(pkt_sk(f->arr[i]), skb)) { 1329 if (i != j) 1330 f->next[idx] = i; 1331 return i; 1332 } 1333 if (++i == num) 1334 i = 0; 1335 } while (i != j); 1336 1337 return idx; 1338 } 1339 1340 static unsigned int fanout_demux_qm(struct packet_fanout *f, 1341 struct sk_buff *skb, 1342 unsigned int num) 1343 { 1344 return skb_get_queue_mapping(skb) % num; 1345 } 1346 1347 static bool fanout_has_flag(struct packet_fanout *f, u16 flag) 1348 { 1349 return f->flags & (flag >> 8); 1350 } 1351 1352 static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev, 1353 struct packet_type *pt, struct net_device *orig_dev) 1354 { 1355 struct packet_fanout *f = pt->af_packet_priv; 1356 unsigned int num = f->num_members; 1357 struct packet_sock *po; 1358 unsigned int idx; 1359 1360 if (!net_eq(dev_net(dev), read_pnet(&f->net)) || 1361 !num) { 1362 kfree_skb(skb); 1363 return 0; 1364 } 1365 1366 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_DEFRAG)) { 1367 skb = ip_check_defrag(skb, IP_DEFRAG_AF_PACKET); 1368 if (!skb) 1369 return 0; 1370 } 1371 switch (f->type) { 1372 case PACKET_FANOUT_HASH: 1373 default: 1374 idx = fanout_demux_hash(f, skb, num); 1375 break; 1376 case PACKET_FANOUT_LB: 1377 idx = fanout_demux_lb(f, skb, num); 1378 break; 1379 case PACKET_FANOUT_CPU: 1380 idx = fanout_demux_cpu(f, skb, num); 1381 break; 1382 case PACKET_FANOUT_RND: 1383 idx = fanout_demux_rnd(f, skb, num); 1384 break; 1385 case PACKET_FANOUT_QM: 1386 idx = fanout_demux_qm(f, skb, num); 1387 break; 1388 case PACKET_FANOUT_ROLLOVER: 1389 idx = fanout_demux_rollover(f, skb, 0, (unsigned int) -1, num); 1390 break; 1391 } 1392 1393 po = pkt_sk(f->arr[idx]); 1394 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER) && 1395 unlikely(!packet_rcv_has_room(po, skb))) { 1396 idx = fanout_demux_rollover(f, skb, idx, idx, num); 1397 po = pkt_sk(f->arr[idx]); 1398 } 1399 1400 return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev); 1401 } 1402 1403 DEFINE_MUTEX(fanout_mutex); 1404 EXPORT_SYMBOL_GPL(fanout_mutex); 1405 static LIST_HEAD(fanout_list); 1406 1407 static void __fanout_link(struct sock *sk, struct packet_sock *po) 1408 { 1409 struct packet_fanout *f = po->fanout; 1410 1411 spin_lock(&f->lock); 1412 f->arr[f->num_members] = sk; 1413 smp_wmb(); 1414 f->num_members++; 1415 spin_unlock(&f->lock); 1416 } 1417 1418 static void __fanout_unlink(struct sock *sk, struct packet_sock *po) 1419 { 1420 struct packet_fanout *f = po->fanout; 1421 int i; 1422 1423 spin_lock(&f->lock); 1424 for (i = 0; i < f->num_members; i++) { 1425 if (f->arr[i] == sk) 1426 break; 1427 } 1428 BUG_ON(i >= f->num_members); 1429 f->arr[i] = f->arr[f->num_members - 1]; 1430 f->num_members--; 1431 spin_unlock(&f->lock); 1432 } 1433 1434 static bool match_fanout_group(struct packet_type *ptype, struct sock *sk) 1435 { 1436 if (ptype->af_packet_priv == (void *)((struct packet_sock *)sk)->fanout) 1437 return true; 1438 1439 return false; 1440 } 1441 1442 static int fanout_add(struct sock *sk, u16 id, u16 type_flags) 1443 { 1444 struct packet_sock *po = pkt_sk(sk); 1445 struct packet_fanout *f, *match; 1446 u8 type = type_flags & 0xff; 1447 u8 flags = type_flags >> 8; 1448 int err; 1449 1450 switch (type) { 1451 case PACKET_FANOUT_ROLLOVER: 1452 if (type_flags & PACKET_FANOUT_FLAG_ROLLOVER) 1453 return -EINVAL; 1454 case PACKET_FANOUT_HASH: 1455 case PACKET_FANOUT_LB: 1456 case PACKET_FANOUT_CPU: 1457 case PACKET_FANOUT_RND: 1458 case PACKET_FANOUT_QM: 1459 break; 1460 default: 1461 return -EINVAL; 1462 } 1463 1464 if (!po->running) 1465 return -EINVAL; 1466 1467 if (po->fanout) 1468 return -EALREADY; 1469 1470 mutex_lock(&fanout_mutex); 1471 match = NULL; 1472 list_for_each_entry(f, &fanout_list, list) { 1473 if (f->id == id && 1474 read_pnet(&f->net) == sock_net(sk)) { 1475 match = f; 1476 break; 1477 } 1478 } 1479 err = -EINVAL; 1480 if (match && match->flags != flags) 1481 goto out; 1482 if (!match) { 1483 err = -ENOMEM; 1484 match = kzalloc(sizeof(*match), GFP_KERNEL); 1485 if (!match) 1486 goto out; 1487 write_pnet(&match->net, sock_net(sk)); 1488 match->id = id; 1489 match->type = type; 1490 match->flags = flags; 1491 atomic_set(&match->rr_cur, 0); 1492 INIT_LIST_HEAD(&match->list); 1493 spin_lock_init(&match->lock); 1494 atomic_set(&match->sk_ref, 0); 1495 match->prot_hook.type = po->prot_hook.type; 1496 match->prot_hook.dev = po->prot_hook.dev; 1497 match->prot_hook.func = packet_rcv_fanout; 1498 match->prot_hook.af_packet_priv = match; 1499 match->prot_hook.id_match = match_fanout_group; 1500 dev_add_pack(&match->prot_hook); 1501 list_add(&match->list, &fanout_list); 1502 } 1503 err = -EINVAL; 1504 if (match->type == type && 1505 match->prot_hook.type == po->prot_hook.type && 1506 match->prot_hook.dev == po->prot_hook.dev) { 1507 err = -ENOSPC; 1508 if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) { 1509 __dev_remove_pack(&po->prot_hook); 1510 po->fanout = match; 1511 atomic_inc(&match->sk_ref); 1512 __fanout_link(sk, po); 1513 err = 0; 1514 } 1515 } 1516 out: 1517 mutex_unlock(&fanout_mutex); 1518 return err; 1519 } 1520 1521 static void fanout_release(struct sock *sk) 1522 { 1523 struct packet_sock *po = pkt_sk(sk); 1524 struct packet_fanout *f; 1525 1526 f = po->fanout; 1527 if (!f) 1528 return; 1529 1530 mutex_lock(&fanout_mutex); 1531 po->fanout = NULL; 1532 1533 if (atomic_dec_and_test(&f->sk_ref)) { 1534 list_del(&f->list); 1535 dev_remove_pack(&f->prot_hook); 1536 kfree(f); 1537 } 1538 mutex_unlock(&fanout_mutex); 1539 } 1540 1541 static const struct proto_ops packet_ops; 1542 1543 static const struct proto_ops packet_ops_spkt; 1544 1545 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev, 1546 struct packet_type *pt, struct net_device *orig_dev) 1547 { 1548 struct sock *sk; 1549 struct sockaddr_pkt *spkt; 1550 1551 /* 1552 * When we registered the protocol we saved the socket in the data 1553 * field for just this event. 1554 */ 1555 1556 sk = pt->af_packet_priv; 1557 1558 /* 1559 * Yank back the headers [hope the device set this 1560 * right or kerboom...] 1561 * 1562 * Incoming packets have ll header pulled, 1563 * push it back. 1564 * 1565 * For outgoing ones skb->data == skb_mac_header(skb) 1566 * so that this procedure is noop. 1567 */ 1568 1569 if (skb->pkt_type == PACKET_LOOPBACK) 1570 goto out; 1571 1572 if (!net_eq(dev_net(dev), sock_net(sk))) 1573 goto out; 1574 1575 skb = skb_share_check(skb, GFP_ATOMIC); 1576 if (skb == NULL) 1577 goto oom; 1578 1579 /* drop any routing info */ 1580 skb_dst_drop(skb); 1581 1582 /* drop conntrack reference */ 1583 nf_reset(skb); 1584 1585 spkt = &PACKET_SKB_CB(skb)->sa.pkt; 1586 1587 skb_push(skb, skb->data - skb_mac_header(skb)); 1588 1589 /* 1590 * The SOCK_PACKET socket receives _all_ frames. 1591 */ 1592 1593 spkt->spkt_family = dev->type; 1594 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device)); 1595 spkt->spkt_protocol = skb->protocol; 1596 1597 /* 1598 * Charge the memory to the socket. This is done specifically 1599 * to prevent sockets using all the memory up. 1600 */ 1601 1602 if (sock_queue_rcv_skb(sk, skb) == 0) 1603 return 0; 1604 1605 out: 1606 kfree_skb(skb); 1607 oom: 1608 return 0; 1609 } 1610 1611 1612 /* 1613 * Output a raw packet to a device layer. This bypasses all the other 1614 * protocol layers and you must therefore supply it with a complete frame 1615 */ 1616 1617 static int packet_sendmsg_spkt(struct socket *sock, struct msghdr *msg, 1618 size_t len) 1619 { 1620 struct sock *sk = sock->sk; 1621 DECLARE_SOCKADDR(struct sockaddr_pkt *, saddr, msg->msg_name); 1622 struct sk_buff *skb = NULL; 1623 struct net_device *dev; 1624 __be16 proto = 0; 1625 int err; 1626 int extra_len = 0; 1627 1628 /* 1629 * Get and verify the address. 1630 */ 1631 1632 if (saddr) { 1633 if (msg->msg_namelen < sizeof(struct sockaddr)) 1634 return -EINVAL; 1635 if (msg->msg_namelen == sizeof(struct sockaddr_pkt)) 1636 proto = saddr->spkt_protocol; 1637 } else 1638 return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */ 1639 1640 /* 1641 * Find the device first to size check it 1642 */ 1643 1644 saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0; 1645 retry: 1646 rcu_read_lock(); 1647 dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device); 1648 err = -ENODEV; 1649 if (dev == NULL) 1650 goto out_unlock; 1651 1652 err = -ENETDOWN; 1653 if (!(dev->flags & IFF_UP)) 1654 goto out_unlock; 1655 1656 /* 1657 * You may not queue a frame bigger than the mtu. This is the lowest level 1658 * raw protocol and you must do your own fragmentation at this level. 1659 */ 1660 1661 if (unlikely(sock_flag(sk, SOCK_NOFCS))) { 1662 if (!netif_supports_nofcs(dev)) { 1663 err = -EPROTONOSUPPORT; 1664 goto out_unlock; 1665 } 1666 extra_len = 4; /* We're doing our own CRC */ 1667 } 1668 1669 err = -EMSGSIZE; 1670 if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len) 1671 goto out_unlock; 1672 1673 if (!skb) { 1674 size_t reserved = LL_RESERVED_SPACE(dev); 1675 int tlen = dev->needed_tailroom; 1676 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0; 1677 1678 rcu_read_unlock(); 1679 skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL); 1680 if (skb == NULL) 1681 return -ENOBUFS; 1682 /* FIXME: Save some space for broken drivers that write a hard 1683 * header at transmission time by themselves. PPP is the notable 1684 * one here. This should really be fixed at the driver level. 1685 */ 1686 skb_reserve(skb, reserved); 1687 skb_reset_network_header(skb); 1688 1689 /* Try to align data part correctly */ 1690 if (hhlen) { 1691 skb->data -= hhlen; 1692 skb->tail -= hhlen; 1693 if (len < hhlen) 1694 skb_reset_network_header(skb); 1695 } 1696 err = memcpy_from_msg(skb_put(skb, len), msg, len); 1697 if (err) 1698 goto out_free; 1699 goto retry; 1700 } 1701 1702 if (len > (dev->mtu + dev->hard_header_len + extra_len)) { 1703 /* Earlier code assumed this would be a VLAN pkt, 1704 * double-check this now that we have the actual 1705 * packet in hand. 1706 */ 1707 struct ethhdr *ehdr; 1708 skb_reset_mac_header(skb); 1709 ehdr = eth_hdr(skb); 1710 if (ehdr->h_proto != htons(ETH_P_8021Q)) { 1711 err = -EMSGSIZE; 1712 goto out_unlock; 1713 } 1714 } 1715 1716 skb->protocol = proto; 1717 skb->dev = dev; 1718 skb->priority = sk->sk_priority; 1719 skb->mark = sk->sk_mark; 1720 1721 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags); 1722 1723 if (unlikely(extra_len == 4)) 1724 skb->no_fcs = 1; 1725 1726 skb_probe_transport_header(skb, 0); 1727 1728 dev_queue_xmit(skb); 1729 rcu_read_unlock(); 1730 return len; 1731 1732 out_unlock: 1733 rcu_read_unlock(); 1734 out_free: 1735 kfree_skb(skb); 1736 return err; 1737 } 1738 1739 static unsigned int run_filter(const struct sk_buff *skb, 1740 const struct sock *sk, 1741 unsigned int res) 1742 { 1743 struct sk_filter *filter; 1744 1745 rcu_read_lock(); 1746 filter = rcu_dereference(sk->sk_filter); 1747 if (filter != NULL) 1748 res = SK_RUN_FILTER(filter, skb); 1749 rcu_read_unlock(); 1750 1751 return res; 1752 } 1753 1754 /* 1755 * This function makes lazy skb cloning in hope that most of packets 1756 * are discarded by BPF. 1757 * 1758 * Note tricky part: we DO mangle shared skb! skb->data, skb->len 1759 * and skb->cb are mangled. It works because (and until) packets 1760 * falling here are owned by current CPU. Output packets are cloned 1761 * by dev_queue_xmit_nit(), input packets are processed by net_bh 1762 * sequencially, so that if we return skb to original state on exit, 1763 * we will not harm anyone. 1764 */ 1765 1766 static int packet_rcv(struct sk_buff *skb, struct net_device *dev, 1767 struct packet_type *pt, struct net_device *orig_dev) 1768 { 1769 struct sock *sk; 1770 struct sockaddr_ll *sll; 1771 struct packet_sock *po; 1772 u8 *skb_head = skb->data; 1773 int skb_len = skb->len; 1774 unsigned int snaplen, res; 1775 1776 if (skb->pkt_type == PACKET_LOOPBACK) 1777 goto drop; 1778 1779 sk = pt->af_packet_priv; 1780 po = pkt_sk(sk); 1781 1782 if (!net_eq(dev_net(dev), sock_net(sk))) 1783 goto drop; 1784 1785 skb->dev = dev; 1786 1787 if (dev->header_ops) { 1788 /* The device has an explicit notion of ll header, 1789 * exported to higher levels. 1790 * 1791 * Otherwise, the device hides details of its frame 1792 * structure, so that corresponding packet head is 1793 * never delivered to user. 1794 */ 1795 if (sk->sk_type != SOCK_DGRAM) 1796 skb_push(skb, skb->data - skb_mac_header(skb)); 1797 else if (skb->pkt_type == PACKET_OUTGOING) { 1798 /* Special case: outgoing packets have ll header at head */ 1799 skb_pull(skb, skb_network_offset(skb)); 1800 } 1801 } 1802 1803 snaplen = skb->len; 1804 1805 res = run_filter(skb, sk, snaplen); 1806 if (!res) 1807 goto drop_n_restore; 1808 if (snaplen > res) 1809 snaplen = res; 1810 1811 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) 1812 goto drop_n_acct; 1813 1814 if (skb_shared(skb)) { 1815 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC); 1816 if (nskb == NULL) 1817 goto drop_n_acct; 1818 1819 if (skb_head != skb->data) { 1820 skb->data = skb_head; 1821 skb->len = skb_len; 1822 } 1823 consume_skb(skb); 1824 skb = nskb; 1825 } 1826 1827 sock_skb_cb_check_size(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8); 1828 1829 sll = &PACKET_SKB_CB(skb)->sa.ll; 1830 sll->sll_hatype = dev->type; 1831 sll->sll_pkttype = skb->pkt_type; 1832 if (unlikely(po->origdev)) 1833 sll->sll_ifindex = orig_dev->ifindex; 1834 else 1835 sll->sll_ifindex = dev->ifindex; 1836 1837 sll->sll_halen = dev_parse_header(skb, sll->sll_addr); 1838 1839 /* sll->sll_family and sll->sll_protocol are set in packet_recvmsg(). 1840 * Use their space for storing the original skb length. 1841 */ 1842 PACKET_SKB_CB(skb)->sa.origlen = skb->len; 1843 1844 if (pskb_trim(skb, snaplen)) 1845 goto drop_n_acct; 1846 1847 skb_set_owner_r(skb, sk); 1848 skb->dev = NULL; 1849 skb_dst_drop(skb); 1850 1851 /* drop conntrack reference */ 1852 nf_reset(skb); 1853 1854 spin_lock(&sk->sk_receive_queue.lock); 1855 po->stats.stats1.tp_packets++; 1856 sock_skb_set_dropcount(sk, skb); 1857 __skb_queue_tail(&sk->sk_receive_queue, skb); 1858 spin_unlock(&sk->sk_receive_queue.lock); 1859 sk->sk_data_ready(sk); 1860 return 0; 1861 1862 drop_n_acct: 1863 spin_lock(&sk->sk_receive_queue.lock); 1864 po->stats.stats1.tp_drops++; 1865 atomic_inc(&sk->sk_drops); 1866 spin_unlock(&sk->sk_receive_queue.lock); 1867 1868 drop_n_restore: 1869 if (skb_head != skb->data && skb_shared(skb)) { 1870 skb->data = skb_head; 1871 skb->len = skb_len; 1872 } 1873 drop: 1874 consume_skb(skb); 1875 return 0; 1876 } 1877 1878 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, 1879 struct packet_type *pt, struct net_device *orig_dev) 1880 { 1881 struct sock *sk; 1882 struct packet_sock *po; 1883 struct sockaddr_ll *sll; 1884 union tpacket_uhdr h; 1885 u8 *skb_head = skb->data; 1886 int skb_len = skb->len; 1887 unsigned int snaplen, res; 1888 unsigned long status = TP_STATUS_USER; 1889 unsigned short macoff, netoff, hdrlen; 1890 struct sk_buff *copy_skb = NULL; 1891 struct timespec ts; 1892 __u32 ts_status; 1893 1894 /* struct tpacket{2,3}_hdr is aligned to a multiple of TPACKET_ALIGNMENT. 1895 * We may add members to them until current aligned size without forcing 1896 * userspace to call getsockopt(..., PACKET_HDRLEN, ...). 1897 */ 1898 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h2)) != 32); 1899 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h3)) != 48); 1900 1901 if (skb->pkt_type == PACKET_LOOPBACK) 1902 goto drop; 1903 1904 sk = pt->af_packet_priv; 1905 po = pkt_sk(sk); 1906 1907 if (!net_eq(dev_net(dev), sock_net(sk))) 1908 goto drop; 1909 1910 if (dev->header_ops) { 1911 if (sk->sk_type != SOCK_DGRAM) 1912 skb_push(skb, skb->data - skb_mac_header(skb)); 1913 else if (skb->pkt_type == PACKET_OUTGOING) { 1914 /* Special case: outgoing packets have ll header at head */ 1915 skb_pull(skb, skb_network_offset(skb)); 1916 } 1917 } 1918 1919 snaplen = skb->len; 1920 1921 res = run_filter(skb, sk, snaplen); 1922 if (!res) 1923 goto drop_n_restore; 1924 1925 if (skb->ip_summed == CHECKSUM_PARTIAL) 1926 status |= TP_STATUS_CSUMNOTREADY; 1927 else if (skb->pkt_type != PACKET_OUTGOING && 1928 (skb->ip_summed == CHECKSUM_COMPLETE || 1929 skb_csum_unnecessary(skb))) 1930 status |= TP_STATUS_CSUM_VALID; 1931 1932 if (snaplen > res) 1933 snaplen = res; 1934 1935 if (sk->sk_type == SOCK_DGRAM) { 1936 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 + 1937 po->tp_reserve; 1938 } else { 1939 unsigned int maclen = skb_network_offset(skb); 1940 netoff = TPACKET_ALIGN(po->tp_hdrlen + 1941 (maclen < 16 ? 16 : maclen)) + 1942 po->tp_reserve; 1943 macoff = netoff - maclen; 1944 } 1945 if (po->tp_version <= TPACKET_V2) { 1946 if (macoff + snaplen > po->rx_ring.frame_size) { 1947 if (po->copy_thresh && 1948 atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) { 1949 if (skb_shared(skb)) { 1950 copy_skb = skb_clone(skb, GFP_ATOMIC); 1951 } else { 1952 copy_skb = skb_get(skb); 1953 skb_head = skb->data; 1954 } 1955 if (copy_skb) 1956 skb_set_owner_r(copy_skb, sk); 1957 } 1958 snaplen = po->rx_ring.frame_size - macoff; 1959 if ((int)snaplen < 0) 1960 snaplen = 0; 1961 } 1962 } else if (unlikely(macoff + snaplen > 1963 GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len)) { 1964 u32 nval; 1965 1966 nval = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len - macoff; 1967 pr_err_once("tpacket_rcv: packet too big, clamped from %u to %u. macoff=%u\n", 1968 snaplen, nval, macoff); 1969 snaplen = nval; 1970 if (unlikely((int)snaplen < 0)) { 1971 snaplen = 0; 1972 macoff = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len; 1973 } 1974 } 1975 spin_lock(&sk->sk_receive_queue.lock); 1976 h.raw = packet_current_rx_frame(po, skb, 1977 TP_STATUS_KERNEL, (macoff+snaplen)); 1978 if (!h.raw) 1979 goto ring_is_full; 1980 if (po->tp_version <= TPACKET_V2) { 1981 packet_increment_rx_head(po, &po->rx_ring); 1982 /* 1983 * LOSING will be reported till you read the stats, 1984 * because it's COR - Clear On Read. 1985 * Anyways, moving it for V1/V2 only as V3 doesn't need this 1986 * at packet level. 1987 */ 1988 if (po->stats.stats1.tp_drops) 1989 status |= TP_STATUS_LOSING; 1990 } 1991 po->stats.stats1.tp_packets++; 1992 if (copy_skb) { 1993 status |= TP_STATUS_COPY; 1994 __skb_queue_tail(&sk->sk_receive_queue, copy_skb); 1995 } 1996 spin_unlock(&sk->sk_receive_queue.lock); 1997 1998 skb_copy_bits(skb, 0, h.raw + macoff, snaplen); 1999 2000 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp))) 2001 getnstimeofday(&ts); 2002 2003 status |= ts_status; 2004 2005 switch (po->tp_version) { 2006 case TPACKET_V1: 2007 h.h1->tp_len = skb->len; 2008 h.h1->tp_snaplen = snaplen; 2009 h.h1->tp_mac = macoff; 2010 h.h1->tp_net = netoff; 2011 h.h1->tp_sec = ts.tv_sec; 2012 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC; 2013 hdrlen = sizeof(*h.h1); 2014 break; 2015 case TPACKET_V2: 2016 h.h2->tp_len = skb->len; 2017 h.h2->tp_snaplen = snaplen; 2018 h.h2->tp_mac = macoff; 2019 h.h2->tp_net = netoff; 2020 h.h2->tp_sec = ts.tv_sec; 2021 h.h2->tp_nsec = ts.tv_nsec; 2022 if (skb_vlan_tag_present(skb)) { 2023 h.h2->tp_vlan_tci = skb_vlan_tag_get(skb); 2024 h.h2->tp_vlan_tpid = ntohs(skb->vlan_proto); 2025 status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID; 2026 } else { 2027 h.h2->tp_vlan_tci = 0; 2028 h.h2->tp_vlan_tpid = 0; 2029 } 2030 memset(h.h2->tp_padding, 0, sizeof(h.h2->tp_padding)); 2031 hdrlen = sizeof(*h.h2); 2032 break; 2033 case TPACKET_V3: 2034 /* tp_nxt_offset,vlan are already populated above. 2035 * So DONT clear those fields here 2036 */ 2037 h.h3->tp_status |= status; 2038 h.h3->tp_len = skb->len; 2039 h.h3->tp_snaplen = snaplen; 2040 h.h3->tp_mac = macoff; 2041 h.h3->tp_net = netoff; 2042 h.h3->tp_sec = ts.tv_sec; 2043 h.h3->tp_nsec = ts.tv_nsec; 2044 memset(h.h3->tp_padding, 0, sizeof(h.h3->tp_padding)); 2045 hdrlen = sizeof(*h.h3); 2046 break; 2047 default: 2048 BUG(); 2049 } 2050 2051 sll = h.raw + TPACKET_ALIGN(hdrlen); 2052 sll->sll_halen = dev_parse_header(skb, sll->sll_addr); 2053 sll->sll_family = AF_PACKET; 2054 sll->sll_hatype = dev->type; 2055 sll->sll_protocol = skb->protocol; 2056 sll->sll_pkttype = skb->pkt_type; 2057 if (unlikely(po->origdev)) 2058 sll->sll_ifindex = orig_dev->ifindex; 2059 else 2060 sll->sll_ifindex = dev->ifindex; 2061 2062 smp_mb(); 2063 2064 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1 2065 if (po->tp_version <= TPACKET_V2) { 2066 u8 *start, *end; 2067 2068 end = (u8 *) PAGE_ALIGN((unsigned long) h.raw + 2069 macoff + snaplen); 2070 2071 for (start = h.raw; start < end; start += PAGE_SIZE) 2072 flush_dcache_page(pgv_to_page(start)); 2073 } 2074 smp_wmb(); 2075 #endif 2076 2077 if (po->tp_version <= TPACKET_V2) { 2078 __packet_set_status(po, h.raw, status); 2079 sk->sk_data_ready(sk); 2080 } else { 2081 prb_clear_blk_fill_status(&po->rx_ring); 2082 } 2083 2084 drop_n_restore: 2085 if (skb_head != skb->data && skb_shared(skb)) { 2086 skb->data = skb_head; 2087 skb->len = skb_len; 2088 } 2089 drop: 2090 kfree_skb(skb); 2091 return 0; 2092 2093 ring_is_full: 2094 po->stats.stats1.tp_drops++; 2095 spin_unlock(&sk->sk_receive_queue.lock); 2096 2097 sk->sk_data_ready(sk); 2098 kfree_skb(copy_skb); 2099 goto drop_n_restore; 2100 } 2101 2102 static void tpacket_destruct_skb(struct sk_buff *skb) 2103 { 2104 struct packet_sock *po = pkt_sk(skb->sk); 2105 2106 if (likely(po->tx_ring.pg_vec)) { 2107 void *ph; 2108 __u32 ts; 2109 2110 ph = skb_shinfo(skb)->destructor_arg; 2111 packet_dec_pending(&po->tx_ring); 2112 2113 ts = __packet_set_timestamp(po, ph, skb); 2114 __packet_set_status(po, ph, TP_STATUS_AVAILABLE | ts); 2115 } 2116 2117 sock_wfree(skb); 2118 } 2119 2120 static bool ll_header_truncated(const struct net_device *dev, int len) 2121 { 2122 /* net device doesn't like empty head */ 2123 if (unlikely(len <= dev->hard_header_len)) { 2124 net_warn_ratelimited("%s: packet size is too short (%d <= %d)\n", 2125 current->comm, len, dev->hard_header_len); 2126 return true; 2127 } 2128 2129 return false; 2130 } 2131 2132 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb, 2133 void *frame, struct net_device *dev, int size_max, 2134 __be16 proto, unsigned char *addr, int hlen) 2135 { 2136 union tpacket_uhdr ph; 2137 int to_write, offset, len, tp_len, nr_frags, len_max; 2138 struct socket *sock = po->sk.sk_socket; 2139 struct page *page; 2140 void *data; 2141 int err; 2142 2143 ph.raw = frame; 2144 2145 skb->protocol = proto; 2146 skb->dev = dev; 2147 skb->priority = po->sk.sk_priority; 2148 skb->mark = po->sk.sk_mark; 2149 sock_tx_timestamp(&po->sk, &skb_shinfo(skb)->tx_flags); 2150 skb_shinfo(skb)->destructor_arg = ph.raw; 2151 2152 switch (po->tp_version) { 2153 case TPACKET_V2: 2154 tp_len = ph.h2->tp_len; 2155 break; 2156 default: 2157 tp_len = ph.h1->tp_len; 2158 break; 2159 } 2160 if (unlikely(tp_len > size_max)) { 2161 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max); 2162 return -EMSGSIZE; 2163 } 2164 2165 skb_reserve(skb, hlen); 2166 skb_reset_network_header(skb); 2167 2168 if (!packet_use_direct_xmit(po)) 2169 skb_probe_transport_header(skb, 0); 2170 if (unlikely(po->tp_tx_has_off)) { 2171 int off_min, off_max, off; 2172 off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll); 2173 off_max = po->tx_ring.frame_size - tp_len; 2174 if (sock->type == SOCK_DGRAM) { 2175 switch (po->tp_version) { 2176 case TPACKET_V2: 2177 off = ph.h2->tp_net; 2178 break; 2179 default: 2180 off = ph.h1->tp_net; 2181 break; 2182 } 2183 } else { 2184 switch (po->tp_version) { 2185 case TPACKET_V2: 2186 off = ph.h2->tp_mac; 2187 break; 2188 default: 2189 off = ph.h1->tp_mac; 2190 break; 2191 } 2192 } 2193 if (unlikely((off < off_min) || (off_max < off))) 2194 return -EINVAL; 2195 data = ph.raw + off; 2196 } else { 2197 data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll); 2198 } 2199 to_write = tp_len; 2200 2201 if (sock->type == SOCK_DGRAM) { 2202 err = dev_hard_header(skb, dev, ntohs(proto), addr, 2203 NULL, tp_len); 2204 if (unlikely(err < 0)) 2205 return -EINVAL; 2206 } else if (dev->hard_header_len) { 2207 if (ll_header_truncated(dev, tp_len)) 2208 return -EINVAL; 2209 2210 skb_push(skb, dev->hard_header_len); 2211 err = skb_store_bits(skb, 0, data, 2212 dev->hard_header_len); 2213 if (unlikely(err)) 2214 return err; 2215 2216 data += dev->hard_header_len; 2217 to_write -= dev->hard_header_len; 2218 } 2219 2220 offset = offset_in_page(data); 2221 len_max = PAGE_SIZE - offset; 2222 len = ((to_write > len_max) ? len_max : to_write); 2223 2224 skb->data_len = to_write; 2225 skb->len += to_write; 2226 skb->truesize += to_write; 2227 atomic_add(to_write, &po->sk.sk_wmem_alloc); 2228 2229 while (likely(to_write)) { 2230 nr_frags = skb_shinfo(skb)->nr_frags; 2231 2232 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) { 2233 pr_err("Packet exceed the number of skb frags(%lu)\n", 2234 MAX_SKB_FRAGS); 2235 return -EFAULT; 2236 } 2237 2238 page = pgv_to_page(data); 2239 data += len; 2240 flush_dcache_page(page); 2241 get_page(page); 2242 skb_fill_page_desc(skb, nr_frags, page, offset, len); 2243 to_write -= len; 2244 offset = 0; 2245 len_max = PAGE_SIZE; 2246 len = ((to_write > len_max) ? len_max : to_write); 2247 } 2248 2249 return tp_len; 2250 } 2251 2252 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg) 2253 { 2254 struct sk_buff *skb; 2255 struct net_device *dev; 2256 __be16 proto; 2257 int err, reserve = 0; 2258 void *ph; 2259 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name); 2260 bool need_wait = !(msg->msg_flags & MSG_DONTWAIT); 2261 int tp_len, size_max; 2262 unsigned char *addr; 2263 int len_sum = 0; 2264 int status = TP_STATUS_AVAILABLE; 2265 int hlen, tlen; 2266 2267 mutex_lock(&po->pg_vec_lock); 2268 2269 if (likely(saddr == NULL)) { 2270 dev = packet_cached_dev_get(po); 2271 proto = po->num; 2272 addr = NULL; 2273 } else { 2274 err = -EINVAL; 2275 if (msg->msg_namelen < sizeof(struct sockaddr_ll)) 2276 goto out; 2277 if (msg->msg_namelen < (saddr->sll_halen 2278 + offsetof(struct sockaddr_ll, 2279 sll_addr))) 2280 goto out; 2281 proto = saddr->sll_protocol; 2282 addr = saddr->sll_addr; 2283 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex); 2284 } 2285 2286 err = -ENXIO; 2287 if (unlikely(dev == NULL)) 2288 goto out; 2289 err = -ENETDOWN; 2290 if (unlikely(!(dev->flags & IFF_UP))) 2291 goto out_put; 2292 2293 reserve = dev->hard_header_len + VLAN_HLEN; 2294 size_max = po->tx_ring.frame_size 2295 - (po->tp_hdrlen - sizeof(struct sockaddr_ll)); 2296 2297 if (size_max > dev->mtu + reserve) 2298 size_max = dev->mtu + reserve; 2299 2300 do { 2301 ph = packet_current_frame(po, &po->tx_ring, 2302 TP_STATUS_SEND_REQUEST); 2303 if (unlikely(ph == NULL)) { 2304 if (need_wait && need_resched()) 2305 schedule(); 2306 continue; 2307 } 2308 2309 status = TP_STATUS_SEND_REQUEST; 2310 hlen = LL_RESERVED_SPACE(dev); 2311 tlen = dev->needed_tailroom; 2312 skb = sock_alloc_send_skb(&po->sk, 2313 hlen + tlen + sizeof(struct sockaddr_ll), 2314 0, &err); 2315 2316 if (unlikely(skb == NULL)) 2317 goto out_status; 2318 2319 tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto, 2320 addr, hlen); 2321 if (tp_len > dev->mtu + dev->hard_header_len) { 2322 struct ethhdr *ehdr; 2323 /* Earlier code assumed this would be a VLAN pkt, 2324 * double-check this now that we have the actual 2325 * packet in hand. 2326 */ 2327 2328 skb_reset_mac_header(skb); 2329 ehdr = eth_hdr(skb); 2330 if (ehdr->h_proto != htons(ETH_P_8021Q)) 2331 tp_len = -EMSGSIZE; 2332 } 2333 if (unlikely(tp_len < 0)) { 2334 if (po->tp_loss) { 2335 __packet_set_status(po, ph, 2336 TP_STATUS_AVAILABLE); 2337 packet_increment_head(&po->tx_ring); 2338 kfree_skb(skb); 2339 continue; 2340 } else { 2341 status = TP_STATUS_WRONG_FORMAT; 2342 err = tp_len; 2343 goto out_status; 2344 } 2345 } 2346 2347 packet_pick_tx_queue(dev, skb); 2348 2349 skb->destructor = tpacket_destruct_skb; 2350 __packet_set_status(po, ph, TP_STATUS_SENDING); 2351 packet_inc_pending(&po->tx_ring); 2352 2353 status = TP_STATUS_SEND_REQUEST; 2354 err = po->xmit(skb); 2355 if (unlikely(err > 0)) { 2356 err = net_xmit_errno(err); 2357 if (err && __packet_get_status(po, ph) == 2358 TP_STATUS_AVAILABLE) { 2359 /* skb was destructed already */ 2360 skb = NULL; 2361 goto out_status; 2362 } 2363 /* 2364 * skb was dropped but not destructed yet; 2365 * let's treat it like congestion or err < 0 2366 */ 2367 err = 0; 2368 } 2369 packet_increment_head(&po->tx_ring); 2370 len_sum += tp_len; 2371 } while (likely((ph != NULL) || 2372 /* Note: packet_read_pending() might be slow if we have 2373 * to call it as it's per_cpu variable, but in fast-path 2374 * we already short-circuit the loop with the first 2375 * condition, and luckily don't have to go that path 2376 * anyway. 2377 */ 2378 (need_wait && packet_read_pending(&po->tx_ring)))); 2379 2380 err = len_sum; 2381 goto out_put; 2382 2383 out_status: 2384 __packet_set_status(po, ph, status); 2385 kfree_skb(skb); 2386 out_put: 2387 dev_put(dev); 2388 out: 2389 mutex_unlock(&po->pg_vec_lock); 2390 return err; 2391 } 2392 2393 static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad, 2394 size_t reserve, size_t len, 2395 size_t linear, int noblock, 2396 int *err) 2397 { 2398 struct sk_buff *skb; 2399 2400 /* Under a page? Don't bother with paged skb. */ 2401 if (prepad + len < PAGE_SIZE || !linear) 2402 linear = len; 2403 2404 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock, 2405 err, 0); 2406 if (!skb) 2407 return NULL; 2408 2409 skb_reserve(skb, reserve); 2410 skb_put(skb, linear); 2411 skb->data_len = len - linear; 2412 skb->len += len - linear; 2413 2414 return skb; 2415 } 2416 2417 static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len) 2418 { 2419 struct sock *sk = sock->sk; 2420 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name); 2421 struct sk_buff *skb; 2422 struct net_device *dev; 2423 __be16 proto; 2424 unsigned char *addr; 2425 int err, reserve = 0; 2426 struct virtio_net_hdr vnet_hdr = { 0 }; 2427 int offset = 0; 2428 int vnet_hdr_len; 2429 struct packet_sock *po = pkt_sk(sk); 2430 unsigned short gso_type = 0; 2431 int hlen, tlen; 2432 int extra_len = 0; 2433 ssize_t n; 2434 2435 /* 2436 * Get and verify the address. 2437 */ 2438 2439 if (likely(saddr == NULL)) { 2440 dev = packet_cached_dev_get(po); 2441 proto = po->num; 2442 addr = NULL; 2443 } else { 2444 err = -EINVAL; 2445 if (msg->msg_namelen < sizeof(struct sockaddr_ll)) 2446 goto out; 2447 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr))) 2448 goto out; 2449 proto = saddr->sll_protocol; 2450 addr = saddr->sll_addr; 2451 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex); 2452 } 2453 2454 err = -ENXIO; 2455 if (unlikely(dev == NULL)) 2456 goto out_unlock; 2457 err = -ENETDOWN; 2458 if (unlikely(!(dev->flags & IFF_UP))) 2459 goto out_unlock; 2460 2461 if (sock->type == SOCK_RAW) 2462 reserve = dev->hard_header_len; 2463 if (po->has_vnet_hdr) { 2464 vnet_hdr_len = sizeof(vnet_hdr); 2465 2466 err = -EINVAL; 2467 if (len < vnet_hdr_len) 2468 goto out_unlock; 2469 2470 len -= vnet_hdr_len; 2471 2472 err = -EFAULT; 2473 n = copy_from_iter(&vnet_hdr, vnet_hdr_len, &msg->msg_iter); 2474 if (n != vnet_hdr_len) 2475 goto out_unlock; 2476 2477 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && 2478 (__virtio16_to_cpu(false, vnet_hdr.csum_start) + 2479 __virtio16_to_cpu(false, vnet_hdr.csum_offset) + 2 > 2480 __virtio16_to_cpu(false, vnet_hdr.hdr_len))) 2481 vnet_hdr.hdr_len = __cpu_to_virtio16(false, 2482 __virtio16_to_cpu(false, vnet_hdr.csum_start) + 2483 __virtio16_to_cpu(false, vnet_hdr.csum_offset) + 2); 2484 2485 err = -EINVAL; 2486 if (__virtio16_to_cpu(false, vnet_hdr.hdr_len) > len) 2487 goto out_unlock; 2488 2489 if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) { 2490 switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { 2491 case VIRTIO_NET_HDR_GSO_TCPV4: 2492 gso_type = SKB_GSO_TCPV4; 2493 break; 2494 case VIRTIO_NET_HDR_GSO_TCPV6: 2495 gso_type = SKB_GSO_TCPV6; 2496 break; 2497 case VIRTIO_NET_HDR_GSO_UDP: 2498 gso_type = SKB_GSO_UDP; 2499 break; 2500 default: 2501 goto out_unlock; 2502 } 2503 2504 if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN) 2505 gso_type |= SKB_GSO_TCP_ECN; 2506 2507 if (vnet_hdr.gso_size == 0) 2508 goto out_unlock; 2509 2510 } 2511 } 2512 2513 if (unlikely(sock_flag(sk, SOCK_NOFCS))) { 2514 if (!netif_supports_nofcs(dev)) { 2515 err = -EPROTONOSUPPORT; 2516 goto out_unlock; 2517 } 2518 extra_len = 4; /* We're doing our own CRC */ 2519 } 2520 2521 err = -EMSGSIZE; 2522 if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN + extra_len)) 2523 goto out_unlock; 2524 2525 err = -ENOBUFS; 2526 hlen = LL_RESERVED_SPACE(dev); 2527 tlen = dev->needed_tailroom; 2528 skb = packet_alloc_skb(sk, hlen + tlen, hlen, len, 2529 __virtio16_to_cpu(false, vnet_hdr.hdr_len), 2530 msg->msg_flags & MSG_DONTWAIT, &err); 2531 if (skb == NULL) 2532 goto out_unlock; 2533 2534 skb_set_network_header(skb, reserve); 2535 2536 err = -EINVAL; 2537 if (sock->type == SOCK_DGRAM) { 2538 offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len); 2539 if (unlikely(offset < 0)) 2540 goto out_free; 2541 } else { 2542 if (ll_header_truncated(dev, len)) 2543 goto out_free; 2544 } 2545 2546 /* Returns -EFAULT on error */ 2547 err = skb_copy_datagram_from_iter(skb, offset, &msg->msg_iter, len); 2548 if (err) 2549 goto out_free; 2550 2551 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags); 2552 2553 if (!gso_type && (len > dev->mtu + reserve + extra_len)) { 2554 /* Earlier code assumed this would be a VLAN pkt, 2555 * double-check this now that we have the actual 2556 * packet in hand. 2557 */ 2558 struct ethhdr *ehdr; 2559 skb_reset_mac_header(skb); 2560 ehdr = eth_hdr(skb); 2561 if (ehdr->h_proto != htons(ETH_P_8021Q)) { 2562 err = -EMSGSIZE; 2563 goto out_free; 2564 } 2565 } 2566 2567 skb->protocol = proto; 2568 skb->dev = dev; 2569 skb->priority = sk->sk_priority; 2570 skb->mark = sk->sk_mark; 2571 2572 packet_pick_tx_queue(dev, skb); 2573 2574 if (po->has_vnet_hdr) { 2575 if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) { 2576 u16 s = __virtio16_to_cpu(false, vnet_hdr.csum_start); 2577 u16 o = __virtio16_to_cpu(false, vnet_hdr.csum_offset); 2578 if (!skb_partial_csum_set(skb, s, o)) { 2579 err = -EINVAL; 2580 goto out_free; 2581 } 2582 } 2583 2584 skb_shinfo(skb)->gso_size = 2585 __virtio16_to_cpu(false, vnet_hdr.gso_size); 2586 skb_shinfo(skb)->gso_type = gso_type; 2587 2588 /* Header must be checked, and gso_segs computed. */ 2589 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY; 2590 skb_shinfo(skb)->gso_segs = 0; 2591 2592 len += vnet_hdr_len; 2593 } 2594 2595 if (!packet_use_direct_xmit(po)) 2596 skb_probe_transport_header(skb, reserve); 2597 if (unlikely(extra_len == 4)) 2598 skb->no_fcs = 1; 2599 2600 err = po->xmit(skb); 2601 if (err > 0 && (err = net_xmit_errno(err)) != 0) 2602 goto out_unlock; 2603 2604 dev_put(dev); 2605 2606 return len; 2607 2608 out_free: 2609 kfree_skb(skb); 2610 out_unlock: 2611 if (dev) 2612 dev_put(dev); 2613 out: 2614 return err; 2615 } 2616 2617 static int packet_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) 2618 { 2619 struct sock *sk = sock->sk; 2620 struct packet_sock *po = pkt_sk(sk); 2621 2622 if (po->tx_ring.pg_vec) 2623 return tpacket_snd(po, msg); 2624 else 2625 return packet_snd(sock, msg, len); 2626 } 2627 2628 /* 2629 * Close a PACKET socket. This is fairly simple. We immediately go 2630 * to 'closed' state and remove our protocol entry in the device list. 2631 */ 2632 2633 static int packet_release(struct socket *sock) 2634 { 2635 struct sock *sk = sock->sk; 2636 struct packet_sock *po; 2637 struct net *net; 2638 union tpacket_req_u req_u; 2639 2640 if (!sk) 2641 return 0; 2642 2643 net = sock_net(sk); 2644 po = pkt_sk(sk); 2645 2646 mutex_lock(&net->packet.sklist_lock); 2647 sk_del_node_init_rcu(sk); 2648 mutex_unlock(&net->packet.sklist_lock); 2649 2650 preempt_disable(); 2651 sock_prot_inuse_add(net, sk->sk_prot, -1); 2652 preempt_enable(); 2653 2654 spin_lock(&po->bind_lock); 2655 unregister_prot_hook(sk, false); 2656 packet_cached_dev_reset(po); 2657 2658 if (po->prot_hook.dev) { 2659 dev_put(po->prot_hook.dev); 2660 po->prot_hook.dev = NULL; 2661 } 2662 spin_unlock(&po->bind_lock); 2663 2664 packet_flush_mclist(sk); 2665 2666 if (po->rx_ring.pg_vec) { 2667 memset(&req_u, 0, sizeof(req_u)); 2668 packet_set_ring(sk, &req_u, 1, 0); 2669 } 2670 2671 if (po->tx_ring.pg_vec) { 2672 memset(&req_u, 0, sizeof(req_u)); 2673 packet_set_ring(sk, &req_u, 1, 1); 2674 } 2675 2676 fanout_release(sk); 2677 2678 synchronize_net(); 2679 /* 2680 * Now the socket is dead. No more input will appear. 2681 */ 2682 sock_orphan(sk); 2683 sock->sk = NULL; 2684 2685 /* Purge queues */ 2686 2687 skb_queue_purge(&sk->sk_receive_queue); 2688 packet_free_pending(po); 2689 sk_refcnt_debug_release(sk); 2690 2691 sock_put(sk); 2692 return 0; 2693 } 2694 2695 /* 2696 * Attach a packet hook. 2697 */ 2698 2699 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 proto) 2700 { 2701 struct packet_sock *po = pkt_sk(sk); 2702 const struct net_device *dev_curr; 2703 __be16 proto_curr; 2704 bool need_rehook; 2705 2706 if (po->fanout) { 2707 if (dev) 2708 dev_put(dev); 2709 2710 return -EINVAL; 2711 } 2712 2713 lock_sock(sk); 2714 spin_lock(&po->bind_lock); 2715 2716 proto_curr = po->prot_hook.type; 2717 dev_curr = po->prot_hook.dev; 2718 2719 need_rehook = proto_curr != proto || dev_curr != dev; 2720 2721 if (need_rehook) { 2722 unregister_prot_hook(sk, true); 2723 2724 po->num = proto; 2725 po->prot_hook.type = proto; 2726 2727 if (po->prot_hook.dev) 2728 dev_put(po->prot_hook.dev); 2729 2730 po->prot_hook.dev = dev; 2731 2732 po->ifindex = dev ? dev->ifindex : 0; 2733 packet_cached_dev_assign(po, dev); 2734 } 2735 2736 if (proto == 0 || !need_rehook) 2737 goto out_unlock; 2738 2739 if (!dev || (dev->flags & IFF_UP)) { 2740 register_prot_hook(sk); 2741 } else { 2742 sk->sk_err = ENETDOWN; 2743 if (!sock_flag(sk, SOCK_DEAD)) 2744 sk->sk_error_report(sk); 2745 } 2746 2747 out_unlock: 2748 spin_unlock(&po->bind_lock); 2749 release_sock(sk); 2750 return 0; 2751 } 2752 2753 /* 2754 * Bind a packet socket to a device 2755 */ 2756 2757 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr, 2758 int addr_len) 2759 { 2760 struct sock *sk = sock->sk; 2761 char name[15]; 2762 struct net_device *dev; 2763 int err = -ENODEV; 2764 2765 /* 2766 * Check legality 2767 */ 2768 2769 if (addr_len != sizeof(struct sockaddr)) 2770 return -EINVAL; 2771 strlcpy(name, uaddr->sa_data, sizeof(name)); 2772 2773 dev = dev_get_by_name(sock_net(sk), name); 2774 if (dev) 2775 err = packet_do_bind(sk, dev, pkt_sk(sk)->num); 2776 return err; 2777 } 2778 2779 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) 2780 { 2781 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr; 2782 struct sock *sk = sock->sk; 2783 struct net_device *dev = NULL; 2784 int err; 2785 2786 2787 /* 2788 * Check legality 2789 */ 2790 2791 if (addr_len < sizeof(struct sockaddr_ll)) 2792 return -EINVAL; 2793 if (sll->sll_family != AF_PACKET) 2794 return -EINVAL; 2795 2796 if (sll->sll_ifindex) { 2797 err = -ENODEV; 2798 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex); 2799 if (dev == NULL) 2800 goto out; 2801 } 2802 err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num); 2803 2804 out: 2805 return err; 2806 } 2807 2808 static struct proto packet_proto = { 2809 .name = "PACKET", 2810 .owner = THIS_MODULE, 2811 .obj_size = sizeof(struct packet_sock), 2812 }; 2813 2814 /* 2815 * Create a packet of type SOCK_PACKET. 2816 */ 2817 2818 static int packet_create(struct net *net, struct socket *sock, int protocol, 2819 int kern) 2820 { 2821 struct sock *sk; 2822 struct packet_sock *po; 2823 __be16 proto = (__force __be16)protocol; /* weird, but documented */ 2824 int err; 2825 2826 if (!ns_capable(net->user_ns, CAP_NET_RAW)) 2827 return -EPERM; 2828 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW && 2829 sock->type != SOCK_PACKET) 2830 return -ESOCKTNOSUPPORT; 2831 2832 sock->state = SS_UNCONNECTED; 2833 2834 err = -ENOBUFS; 2835 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto); 2836 if (sk == NULL) 2837 goto out; 2838 2839 sock->ops = &packet_ops; 2840 if (sock->type == SOCK_PACKET) 2841 sock->ops = &packet_ops_spkt; 2842 2843 sock_init_data(sock, sk); 2844 2845 po = pkt_sk(sk); 2846 sk->sk_family = PF_PACKET; 2847 po->num = proto; 2848 po->xmit = dev_queue_xmit; 2849 2850 err = packet_alloc_pending(po); 2851 if (err) 2852 goto out2; 2853 2854 packet_cached_dev_reset(po); 2855 2856 sk->sk_destruct = packet_sock_destruct; 2857 sk_refcnt_debug_inc(sk); 2858 2859 /* 2860 * Attach a protocol block 2861 */ 2862 2863 spin_lock_init(&po->bind_lock); 2864 mutex_init(&po->pg_vec_lock); 2865 po->prot_hook.func = packet_rcv; 2866 2867 if (sock->type == SOCK_PACKET) 2868 po->prot_hook.func = packet_rcv_spkt; 2869 2870 po->prot_hook.af_packet_priv = sk; 2871 2872 if (proto) { 2873 po->prot_hook.type = proto; 2874 register_prot_hook(sk); 2875 } 2876 2877 mutex_lock(&net->packet.sklist_lock); 2878 sk_add_node_rcu(sk, &net->packet.sklist); 2879 mutex_unlock(&net->packet.sklist_lock); 2880 2881 preempt_disable(); 2882 sock_prot_inuse_add(net, &packet_proto, 1); 2883 preempt_enable(); 2884 2885 return 0; 2886 out2: 2887 sk_free(sk); 2888 out: 2889 return err; 2890 } 2891 2892 /* 2893 * Pull a packet from our receive queue and hand it to the user. 2894 * If necessary we block. 2895 */ 2896 2897 static int packet_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, 2898 int flags) 2899 { 2900 struct sock *sk = sock->sk; 2901 struct sk_buff *skb; 2902 int copied, err; 2903 int vnet_hdr_len = 0; 2904 unsigned int origlen = 0; 2905 2906 err = -EINVAL; 2907 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE)) 2908 goto out; 2909 2910 #if 0 2911 /* What error should we return now? EUNATTACH? */ 2912 if (pkt_sk(sk)->ifindex < 0) 2913 return -ENODEV; 2914 #endif 2915 2916 if (flags & MSG_ERRQUEUE) { 2917 err = sock_recv_errqueue(sk, msg, len, 2918 SOL_PACKET, PACKET_TX_TIMESTAMP); 2919 goto out; 2920 } 2921 2922 /* 2923 * Call the generic datagram receiver. This handles all sorts 2924 * of horrible races and re-entrancy so we can forget about it 2925 * in the protocol layers. 2926 * 2927 * Now it will return ENETDOWN, if device have just gone down, 2928 * but then it will block. 2929 */ 2930 2931 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err); 2932 2933 /* 2934 * An error occurred so return it. Because skb_recv_datagram() 2935 * handles the blocking we don't see and worry about blocking 2936 * retries. 2937 */ 2938 2939 if (skb == NULL) 2940 goto out; 2941 2942 if (pkt_sk(sk)->has_vnet_hdr) { 2943 struct virtio_net_hdr vnet_hdr = { 0 }; 2944 2945 err = -EINVAL; 2946 vnet_hdr_len = sizeof(vnet_hdr); 2947 if (len < vnet_hdr_len) 2948 goto out_free; 2949 2950 len -= vnet_hdr_len; 2951 2952 if (skb_is_gso(skb)) { 2953 struct skb_shared_info *sinfo = skb_shinfo(skb); 2954 2955 /* This is a hint as to how much should be linear. */ 2956 vnet_hdr.hdr_len = 2957 __cpu_to_virtio16(false, skb_headlen(skb)); 2958 vnet_hdr.gso_size = 2959 __cpu_to_virtio16(false, sinfo->gso_size); 2960 if (sinfo->gso_type & SKB_GSO_TCPV4) 2961 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4; 2962 else if (sinfo->gso_type & SKB_GSO_TCPV6) 2963 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6; 2964 else if (sinfo->gso_type & SKB_GSO_UDP) 2965 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP; 2966 else if (sinfo->gso_type & SKB_GSO_FCOE) 2967 goto out_free; 2968 else 2969 BUG(); 2970 if (sinfo->gso_type & SKB_GSO_TCP_ECN) 2971 vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN; 2972 } else 2973 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE; 2974 2975 if (skb->ip_summed == CHECKSUM_PARTIAL) { 2976 vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; 2977 vnet_hdr.csum_start = __cpu_to_virtio16(false, 2978 skb_checksum_start_offset(skb)); 2979 vnet_hdr.csum_offset = __cpu_to_virtio16(false, 2980 skb->csum_offset); 2981 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) { 2982 vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID; 2983 } /* else everything is zero */ 2984 2985 err = memcpy_to_msg(msg, (void *)&vnet_hdr, vnet_hdr_len); 2986 if (err < 0) 2987 goto out_free; 2988 } 2989 2990 /* You lose any data beyond the buffer you gave. If it worries 2991 * a user program they can ask the device for its MTU 2992 * anyway. 2993 */ 2994 copied = skb->len; 2995 if (copied > len) { 2996 copied = len; 2997 msg->msg_flags |= MSG_TRUNC; 2998 } 2999 3000 err = skb_copy_datagram_msg(skb, 0, msg, copied); 3001 if (err) 3002 goto out_free; 3003 3004 if (sock->type != SOCK_PACKET) { 3005 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll; 3006 3007 /* Original length was stored in sockaddr_ll fields */ 3008 origlen = PACKET_SKB_CB(skb)->sa.origlen; 3009 sll->sll_family = AF_PACKET; 3010 sll->sll_protocol = skb->protocol; 3011 } 3012 3013 sock_recv_ts_and_drops(msg, sk, skb); 3014 3015 if (msg->msg_name) { 3016 /* If the address length field is there to be filled 3017 * in, we fill it in now. 3018 */ 3019 if (sock->type == SOCK_PACKET) { 3020 __sockaddr_check_size(sizeof(struct sockaddr_pkt)); 3021 msg->msg_namelen = sizeof(struct sockaddr_pkt); 3022 } else { 3023 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll; 3024 3025 msg->msg_namelen = sll->sll_halen + 3026 offsetof(struct sockaddr_ll, sll_addr); 3027 } 3028 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa, 3029 msg->msg_namelen); 3030 } 3031 3032 if (pkt_sk(sk)->auxdata) { 3033 struct tpacket_auxdata aux; 3034 3035 aux.tp_status = TP_STATUS_USER; 3036 if (skb->ip_summed == CHECKSUM_PARTIAL) 3037 aux.tp_status |= TP_STATUS_CSUMNOTREADY; 3038 else if (skb->pkt_type != PACKET_OUTGOING && 3039 (skb->ip_summed == CHECKSUM_COMPLETE || 3040 skb_csum_unnecessary(skb))) 3041 aux.tp_status |= TP_STATUS_CSUM_VALID; 3042 3043 aux.tp_len = origlen; 3044 aux.tp_snaplen = skb->len; 3045 aux.tp_mac = 0; 3046 aux.tp_net = skb_network_offset(skb); 3047 if (skb_vlan_tag_present(skb)) { 3048 aux.tp_vlan_tci = skb_vlan_tag_get(skb); 3049 aux.tp_vlan_tpid = ntohs(skb->vlan_proto); 3050 aux.tp_status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID; 3051 } else { 3052 aux.tp_vlan_tci = 0; 3053 aux.tp_vlan_tpid = 0; 3054 } 3055 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux); 3056 } 3057 3058 /* 3059 * Free or return the buffer as appropriate. Again this 3060 * hides all the races and re-entrancy issues from us. 3061 */ 3062 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied); 3063 3064 out_free: 3065 skb_free_datagram(sk, skb); 3066 out: 3067 return err; 3068 } 3069 3070 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr, 3071 int *uaddr_len, int peer) 3072 { 3073 struct net_device *dev; 3074 struct sock *sk = sock->sk; 3075 3076 if (peer) 3077 return -EOPNOTSUPP; 3078 3079 uaddr->sa_family = AF_PACKET; 3080 memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data)); 3081 rcu_read_lock(); 3082 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex); 3083 if (dev) 3084 strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data)); 3085 rcu_read_unlock(); 3086 *uaddr_len = sizeof(*uaddr); 3087 3088 return 0; 3089 } 3090 3091 static int packet_getname(struct socket *sock, struct sockaddr *uaddr, 3092 int *uaddr_len, int peer) 3093 { 3094 struct net_device *dev; 3095 struct sock *sk = sock->sk; 3096 struct packet_sock *po = pkt_sk(sk); 3097 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr); 3098 3099 if (peer) 3100 return -EOPNOTSUPP; 3101 3102 sll->sll_family = AF_PACKET; 3103 sll->sll_ifindex = po->ifindex; 3104 sll->sll_protocol = po->num; 3105 sll->sll_pkttype = 0; 3106 rcu_read_lock(); 3107 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex); 3108 if (dev) { 3109 sll->sll_hatype = dev->type; 3110 sll->sll_halen = dev->addr_len; 3111 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len); 3112 } else { 3113 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */ 3114 sll->sll_halen = 0; 3115 } 3116 rcu_read_unlock(); 3117 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen; 3118 3119 return 0; 3120 } 3121 3122 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i, 3123 int what) 3124 { 3125 switch (i->type) { 3126 case PACKET_MR_MULTICAST: 3127 if (i->alen != dev->addr_len) 3128 return -EINVAL; 3129 if (what > 0) 3130 return dev_mc_add(dev, i->addr); 3131 else 3132 return dev_mc_del(dev, i->addr); 3133 break; 3134 case PACKET_MR_PROMISC: 3135 return dev_set_promiscuity(dev, what); 3136 case PACKET_MR_ALLMULTI: 3137 return dev_set_allmulti(dev, what); 3138 case PACKET_MR_UNICAST: 3139 if (i->alen != dev->addr_len) 3140 return -EINVAL; 3141 if (what > 0) 3142 return dev_uc_add(dev, i->addr); 3143 else 3144 return dev_uc_del(dev, i->addr); 3145 break; 3146 default: 3147 break; 3148 } 3149 return 0; 3150 } 3151 3152 static void packet_dev_mclist_delete(struct net_device *dev, 3153 struct packet_mclist **mlp) 3154 { 3155 struct packet_mclist *ml; 3156 3157 while ((ml = *mlp) != NULL) { 3158 if (ml->ifindex == dev->ifindex) { 3159 packet_dev_mc(dev, ml, -1); 3160 *mlp = ml->next; 3161 kfree(ml); 3162 } else 3163 mlp = &ml->next; 3164 } 3165 } 3166 3167 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq) 3168 { 3169 struct packet_sock *po = pkt_sk(sk); 3170 struct packet_mclist *ml, *i; 3171 struct net_device *dev; 3172 int err; 3173 3174 rtnl_lock(); 3175 3176 err = -ENODEV; 3177 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex); 3178 if (!dev) 3179 goto done; 3180 3181 err = -EINVAL; 3182 if (mreq->mr_alen > dev->addr_len) 3183 goto done; 3184 3185 err = -ENOBUFS; 3186 i = kmalloc(sizeof(*i), GFP_KERNEL); 3187 if (i == NULL) 3188 goto done; 3189 3190 err = 0; 3191 for (ml = po->mclist; ml; ml = ml->next) { 3192 if (ml->ifindex == mreq->mr_ifindex && 3193 ml->type == mreq->mr_type && 3194 ml->alen == mreq->mr_alen && 3195 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) { 3196 ml->count++; 3197 /* Free the new element ... */ 3198 kfree(i); 3199 goto done; 3200 } 3201 } 3202 3203 i->type = mreq->mr_type; 3204 i->ifindex = mreq->mr_ifindex; 3205 i->alen = mreq->mr_alen; 3206 memcpy(i->addr, mreq->mr_address, i->alen); 3207 i->count = 1; 3208 i->next = po->mclist; 3209 po->mclist = i; 3210 err = packet_dev_mc(dev, i, 1); 3211 if (err) { 3212 po->mclist = i->next; 3213 kfree(i); 3214 } 3215 3216 done: 3217 rtnl_unlock(); 3218 return err; 3219 } 3220 3221 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq) 3222 { 3223 struct packet_mclist *ml, **mlp; 3224 3225 rtnl_lock(); 3226 3227 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) { 3228 if (ml->ifindex == mreq->mr_ifindex && 3229 ml->type == mreq->mr_type && 3230 ml->alen == mreq->mr_alen && 3231 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) { 3232 if (--ml->count == 0) { 3233 struct net_device *dev; 3234 *mlp = ml->next; 3235 dev = __dev_get_by_index(sock_net(sk), ml->ifindex); 3236 if (dev) 3237 packet_dev_mc(dev, ml, -1); 3238 kfree(ml); 3239 } 3240 break; 3241 } 3242 } 3243 rtnl_unlock(); 3244 return 0; 3245 } 3246 3247 static void packet_flush_mclist(struct sock *sk) 3248 { 3249 struct packet_sock *po = pkt_sk(sk); 3250 struct packet_mclist *ml; 3251 3252 if (!po->mclist) 3253 return; 3254 3255 rtnl_lock(); 3256 while ((ml = po->mclist) != NULL) { 3257 struct net_device *dev; 3258 3259 po->mclist = ml->next; 3260 dev = __dev_get_by_index(sock_net(sk), ml->ifindex); 3261 if (dev != NULL) 3262 packet_dev_mc(dev, ml, -1); 3263 kfree(ml); 3264 } 3265 rtnl_unlock(); 3266 } 3267 3268 static int 3269 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen) 3270 { 3271 struct sock *sk = sock->sk; 3272 struct packet_sock *po = pkt_sk(sk); 3273 int ret; 3274 3275 if (level != SOL_PACKET) 3276 return -ENOPROTOOPT; 3277 3278 switch (optname) { 3279 case PACKET_ADD_MEMBERSHIP: 3280 case PACKET_DROP_MEMBERSHIP: 3281 { 3282 struct packet_mreq_max mreq; 3283 int len = optlen; 3284 memset(&mreq, 0, sizeof(mreq)); 3285 if (len < sizeof(struct packet_mreq)) 3286 return -EINVAL; 3287 if (len > sizeof(mreq)) 3288 len = sizeof(mreq); 3289 if (copy_from_user(&mreq, optval, len)) 3290 return -EFAULT; 3291 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address))) 3292 return -EINVAL; 3293 if (optname == PACKET_ADD_MEMBERSHIP) 3294 ret = packet_mc_add(sk, &mreq); 3295 else 3296 ret = packet_mc_drop(sk, &mreq); 3297 return ret; 3298 } 3299 3300 case PACKET_RX_RING: 3301 case PACKET_TX_RING: 3302 { 3303 union tpacket_req_u req_u; 3304 int len; 3305 3306 switch (po->tp_version) { 3307 case TPACKET_V1: 3308 case TPACKET_V2: 3309 len = sizeof(req_u.req); 3310 break; 3311 case TPACKET_V3: 3312 default: 3313 len = sizeof(req_u.req3); 3314 break; 3315 } 3316 if (optlen < len) 3317 return -EINVAL; 3318 if (pkt_sk(sk)->has_vnet_hdr) 3319 return -EINVAL; 3320 if (copy_from_user(&req_u.req, optval, len)) 3321 return -EFAULT; 3322 return packet_set_ring(sk, &req_u, 0, 3323 optname == PACKET_TX_RING); 3324 } 3325 case PACKET_COPY_THRESH: 3326 { 3327 int val; 3328 3329 if (optlen != sizeof(val)) 3330 return -EINVAL; 3331 if (copy_from_user(&val, optval, sizeof(val))) 3332 return -EFAULT; 3333 3334 pkt_sk(sk)->copy_thresh = val; 3335 return 0; 3336 } 3337 case PACKET_VERSION: 3338 { 3339 int val; 3340 3341 if (optlen != sizeof(val)) 3342 return -EINVAL; 3343 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 3344 return -EBUSY; 3345 if (copy_from_user(&val, optval, sizeof(val))) 3346 return -EFAULT; 3347 switch (val) { 3348 case TPACKET_V1: 3349 case TPACKET_V2: 3350 case TPACKET_V3: 3351 po->tp_version = val; 3352 return 0; 3353 default: 3354 return -EINVAL; 3355 } 3356 } 3357 case PACKET_RESERVE: 3358 { 3359 unsigned int val; 3360 3361 if (optlen != sizeof(val)) 3362 return -EINVAL; 3363 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 3364 return -EBUSY; 3365 if (copy_from_user(&val, optval, sizeof(val))) 3366 return -EFAULT; 3367 po->tp_reserve = val; 3368 return 0; 3369 } 3370 case PACKET_LOSS: 3371 { 3372 unsigned int val; 3373 3374 if (optlen != sizeof(val)) 3375 return -EINVAL; 3376 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 3377 return -EBUSY; 3378 if (copy_from_user(&val, optval, sizeof(val))) 3379 return -EFAULT; 3380 po->tp_loss = !!val; 3381 return 0; 3382 } 3383 case PACKET_AUXDATA: 3384 { 3385 int val; 3386 3387 if (optlen < sizeof(val)) 3388 return -EINVAL; 3389 if (copy_from_user(&val, optval, sizeof(val))) 3390 return -EFAULT; 3391 3392 po->auxdata = !!val; 3393 return 0; 3394 } 3395 case PACKET_ORIGDEV: 3396 { 3397 int val; 3398 3399 if (optlen < sizeof(val)) 3400 return -EINVAL; 3401 if (copy_from_user(&val, optval, sizeof(val))) 3402 return -EFAULT; 3403 3404 po->origdev = !!val; 3405 return 0; 3406 } 3407 case PACKET_VNET_HDR: 3408 { 3409 int val; 3410 3411 if (sock->type != SOCK_RAW) 3412 return -EINVAL; 3413 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 3414 return -EBUSY; 3415 if (optlen < sizeof(val)) 3416 return -EINVAL; 3417 if (copy_from_user(&val, optval, sizeof(val))) 3418 return -EFAULT; 3419 3420 po->has_vnet_hdr = !!val; 3421 return 0; 3422 } 3423 case PACKET_TIMESTAMP: 3424 { 3425 int val; 3426 3427 if (optlen != sizeof(val)) 3428 return -EINVAL; 3429 if (copy_from_user(&val, optval, sizeof(val))) 3430 return -EFAULT; 3431 3432 po->tp_tstamp = val; 3433 return 0; 3434 } 3435 case PACKET_FANOUT: 3436 { 3437 int val; 3438 3439 if (optlen != sizeof(val)) 3440 return -EINVAL; 3441 if (copy_from_user(&val, optval, sizeof(val))) 3442 return -EFAULT; 3443 3444 return fanout_add(sk, val & 0xffff, val >> 16); 3445 } 3446 case PACKET_TX_HAS_OFF: 3447 { 3448 unsigned int val; 3449 3450 if (optlen != sizeof(val)) 3451 return -EINVAL; 3452 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 3453 return -EBUSY; 3454 if (copy_from_user(&val, optval, sizeof(val))) 3455 return -EFAULT; 3456 po->tp_tx_has_off = !!val; 3457 return 0; 3458 } 3459 case PACKET_QDISC_BYPASS: 3460 { 3461 int val; 3462 3463 if (optlen != sizeof(val)) 3464 return -EINVAL; 3465 if (copy_from_user(&val, optval, sizeof(val))) 3466 return -EFAULT; 3467 3468 po->xmit = val ? packet_direct_xmit : dev_queue_xmit; 3469 return 0; 3470 } 3471 default: 3472 return -ENOPROTOOPT; 3473 } 3474 } 3475 3476 static int packet_getsockopt(struct socket *sock, int level, int optname, 3477 char __user *optval, int __user *optlen) 3478 { 3479 int len; 3480 int val, lv = sizeof(val); 3481 struct sock *sk = sock->sk; 3482 struct packet_sock *po = pkt_sk(sk); 3483 void *data = &val; 3484 union tpacket_stats_u st; 3485 3486 if (level != SOL_PACKET) 3487 return -ENOPROTOOPT; 3488 3489 if (get_user(len, optlen)) 3490 return -EFAULT; 3491 3492 if (len < 0) 3493 return -EINVAL; 3494 3495 switch (optname) { 3496 case PACKET_STATISTICS: 3497 spin_lock_bh(&sk->sk_receive_queue.lock); 3498 memcpy(&st, &po->stats, sizeof(st)); 3499 memset(&po->stats, 0, sizeof(po->stats)); 3500 spin_unlock_bh(&sk->sk_receive_queue.lock); 3501 3502 if (po->tp_version == TPACKET_V3) { 3503 lv = sizeof(struct tpacket_stats_v3); 3504 st.stats3.tp_packets += st.stats3.tp_drops; 3505 data = &st.stats3; 3506 } else { 3507 lv = sizeof(struct tpacket_stats); 3508 st.stats1.tp_packets += st.stats1.tp_drops; 3509 data = &st.stats1; 3510 } 3511 3512 break; 3513 case PACKET_AUXDATA: 3514 val = po->auxdata; 3515 break; 3516 case PACKET_ORIGDEV: 3517 val = po->origdev; 3518 break; 3519 case PACKET_VNET_HDR: 3520 val = po->has_vnet_hdr; 3521 break; 3522 case PACKET_VERSION: 3523 val = po->tp_version; 3524 break; 3525 case PACKET_HDRLEN: 3526 if (len > sizeof(int)) 3527 len = sizeof(int); 3528 if (copy_from_user(&val, optval, len)) 3529 return -EFAULT; 3530 switch (val) { 3531 case TPACKET_V1: 3532 val = sizeof(struct tpacket_hdr); 3533 break; 3534 case TPACKET_V2: 3535 val = sizeof(struct tpacket2_hdr); 3536 break; 3537 case TPACKET_V3: 3538 val = sizeof(struct tpacket3_hdr); 3539 break; 3540 default: 3541 return -EINVAL; 3542 } 3543 break; 3544 case PACKET_RESERVE: 3545 val = po->tp_reserve; 3546 break; 3547 case PACKET_LOSS: 3548 val = po->tp_loss; 3549 break; 3550 case PACKET_TIMESTAMP: 3551 val = po->tp_tstamp; 3552 break; 3553 case PACKET_FANOUT: 3554 val = (po->fanout ? 3555 ((u32)po->fanout->id | 3556 ((u32)po->fanout->type << 16) | 3557 ((u32)po->fanout->flags << 24)) : 3558 0); 3559 break; 3560 case PACKET_TX_HAS_OFF: 3561 val = po->tp_tx_has_off; 3562 break; 3563 case PACKET_QDISC_BYPASS: 3564 val = packet_use_direct_xmit(po); 3565 break; 3566 default: 3567 return -ENOPROTOOPT; 3568 } 3569 3570 if (len > lv) 3571 len = lv; 3572 if (put_user(len, optlen)) 3573 return -EFAULT; 3574 if (copy_to_user(optval, data, len)) 3575 return -EFAULT; 3576 return 0; 3577 } 3578 3579 3580 static int packet_notifier(struct notifier_block *this, 3581 unsigned long msg, void *ptr) 3582 { 3583 struct sock *sk; 3584 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 3585 struct net *net = dev_net(dev); 3586 3587 rcu_read_lock(); 3588 sk_for_each_rcu(sk, &net->packet.sklist) { 3589 struct packet_sock *po = pkt_sk(sk); 3590 3591 switch (msg) { 3592 case NETDEV_UNREGISTER: 3593 if (po->mclist) 3594 packet_dev_mclist_delete(dev, &po->mclist); 3595 /* fallthrough */ 3596 3597 case NETDEV_DOWN: 3598 if (dev->ifindex == po->ifindex) { 3599 spin_lock(&po->bind_lock); 3600 if (po->running) { 3601 __unregister_prot_hook(sk, false); 3602 sk->sk_err = ENETDOWN; 3603 if (!sock_flag(sk, SOCK_DEAD)) 3604 sk->sk_error_report(sk); 3605 } 3606 if (msg == NETDEV_UNREGISTER) { 3607 packet_cached_dev_reset(po); 3608 po->ifindex = -1; 3609 if (po->prot_hook.dev) 3610 dev_put(po->prot_hook.dev); 3611 po->prot_hook.dev = NULL; 3612 } 3613 spin_unlock(&po->bind_lock); 3614 } 3615 break; 3616 case NETDEV_UP: 3617 if (dev->ifindex == po->ifindex) { 3618 spin_lock(&po->bind_lock); 3619 if (po->num) 3620 register_prot_hook(sk); 3621 spin_unlock(&po->bind_lock); 3622 } 3623 break; 3624 } 3625 } 3626 rcu_read_unlock(); 3627 return NOTIFY_DONE; 3628 } 3629 3630 3631 static int packet_ioctl(struct socket *sock, unsigned int cmd, 3632 unsigned long arg) 3633 { 3634 struct sock *sk = sock->sk; 3635 3636 switch (cmd) { 3637 case SIOCOUTQ: 3638 { 3639 int amount = sk_wmem_alloc_get(sk); 3640 3641 return put_user(amount, (int __user *)arg); 3642 } 3643 case SIOCINQ: 3644 { 3645 struct sk_buff *skb; 3646 int amount = 0; 3647 3648 spin_lock_bh(&sk->sk_receive_queue.lock); 3649 skb = skb_peek(&sk->sk_receive_queue); 3650 if (skb) 3651 amount = skb->len; 3652 spin_unlock_bh(&sk->sk_receive_queue.lock); 3653 return put_user(amount, (int __user *)arg); 3654 } 3655 case SIOCGSTAMP: 3656 return sock_get_timestamp(sk, (struct timeval __user *)arg); 3657 case SIOCGSTAMPNS: 3658 return sock_get_timestampns(sk, (struct timespec __user *)arg); 3659 3660 #ifdef CONFIG_INET 3661 case SIOCADDRT: 3662 case SIOCDELRT: 3663 case SIOCDARP: 3664 case SIOCGARP: 3665 case SIOCSARP: 3666 case SIOCGIFADDR: 3667 case SIOCSIFADDR: 3668 case SIOCGIFBRDADDR: 3669 case SIOCSIFBRDADDR: 3670 case SIOCGIFNETMASK: 3671 case SIOCSIFNETMASK: 3672 case SIOCGIFDSTADDR: 3673 case SIOCSIFDSTADDR: 3674 case SIOCSIFFLAGS: 3675 return inet_dgram_ops.ioctl(sock, cmd, arg); 3676 #endif 3677 3678 default: 3679 return -ENOIOCTLCMD; 3680 } 3681 return 0; 3682 } 3683 3684 static unsigned int packet_poll(struct file *file, struct socket *sock, 3685 poll_table *wait) 3686 { 3687 struct sock *sk = sock->sk; 3688 struct packet_sock *po = pkt_sk(sk); 3689 unsigned int mask = datagram_poll(file, sock, wait); 3690 3691 spin_lock_bh(&sk->sk_receive_queue.lock); 3692 if (po->rx_ring.pg_vec) { 3693 if (!packet_previous_rx_frame(po, &po->rx_ring, 3694 TP_STATUS_KERNEL)) 3695 mask |= POLLIN | POLLRDNORM; 3696 } 3697 spin_unlock_bh(&sk->sk_receive_queue.lock); 3698 spin_lock_bh(&sk->sk_write_queue.lock); 3699 if (po->tx_ring.pg_vec) { 3700 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE)) 3701 mask |= POLLOUT | POLLWRNORM; 3702 } 3703 spin_unlock_bh(&sk->sk_write_queue.lock); 3704 return mask; 3705 } 3706 3707 3708 /* Dirty? Well, I still did not learn better way to account 3709 * for user mmaps. 3710 */ 3711 3712 static void packet_mm_open(struct vm_area_struct *vma) 3713 { 3714 struct file *file = vma->vm_file; 3715 struct socket *sock = file->private_data; 3716 struct sock *sk = sock->sk; 3717 3718 if (sk) 3719 atomic_inc(&pkt_sk(sk)->mapped); 3720 } 3721 3722 static void packet_mm_close(struct vm_area_struct *vma) 3723 { 3724 struct file *file = vma->vm_file; 3725 struct socket *sock = file->private_data; 3726 struct sock *sk = sock->sk; 3727 3728 if (sk) 3729 atomic_dec(&pkt_sk(sk)->mapped); 3730 } 3731 3732 static const struct vm_operations_struct packet_mmap_ops = { 3733 .open = packet_mm_open, 3734 .close = packet_mm_close, 3735 }; 3736 3737 static void free_pg_vec(struct pgv *pg_vec, unsigned int order, 3738 unsigned int len) 3739 { 3740 int i; 3741 3742 for (i = 0; i < len; i++) { 3743 if (likely(pg_vec[i].buffer)) { 3744 if (is_vmalloc_addr(pg_vec[i].buffer)) 3745 vfree(pg_vec[i].buffer); 3746 else 3747 free_pages((unsigned long)pg_vec[i].buffer, 3748 order); 3749 pg_vec[i].buffer = NULL; 3750 } 3751 } 3752 kfree(pg_vec); 3753 } 3754 3755 static char *alloc_one_pg_vec_page(unsigned long order) 3756 { 3757 char *buffer; 3758 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP | 3759 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY; 3760 3761 buffer = (char *) __get_free_pages(gfp_flags, order); 3762 if (buffer) 3763 return buffer; 3764 3765 /* __get_free_pages failed, fall back to vmalloc */ 3766 buffer = vzalloc((1 << order) * PAGE_SIZE); 3767 if (buffer) 3768 return buffer; 3769 3770 /* vmalloc failed, lets dig into swap here */ 3771 gfp_flags &= ~__GFP_NORETRY; 3772 buffer = (char *) __get_free_pages(gfp_flags, order); 3773 if (buffer) 3774 return buffer; 3775 3776 /* complete and utter failure */ 3777 return NULL; 3778 } 3779 3780 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order) 3781 { 3782 unsigned int block_nr = req->tp_block_nr; 3783 struct pgv *pg_vec; 3784 int i; 3785 3786 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL); 3787 if (unlikely(!pg_vec)) 3788 goto out; 3789 3790 for (i = 0; i < block_nr; i++) { 3791 pg_vec[i].buffer = alloc_one_pg_vec_page(order); 3792 if (unlikely(!pg_vec[i].buffer)) 3793 goto out_free_pgvec; 3794 } 3795 3796 out: 3797 return pg_vec; 3798 3799 out_free_pgvec: 3800 free_pg_vec(pg_vec, order, block_nr); 3801 pg_vec = NULL; 3802 goto out; 3803 } 3804 3805 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u, 3806 int closing, int tx_ring) 3807 { 3808 struct pgv *pg_vec = NULL; 3809 struct packet_sock *po = pkt_sk(sk); 3810 int was_running, order = 0; 3811 struct packet_ring_buffer *rb; 3812 struct sk_buff_head *rb_queue; 3813 __be16 num; 3814 int err = -EINVAL; 3815 /* Added to avoid minimal code churn */ 3816 struct tpacket_req *req = &req_u->req; 3817 3818 /* Opening a Tx-ring is NOT supported in TPACKET_V3 */ 3819 if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) { 3820 WARN(1, "Tx-ring is not supported.\n"); 3821 goto out; 3822 } 3823 3824 rb = tx_ring ? &po->tx_ring : &po->rx_ring; 3825 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue; 3826 3827 err = -EBUSY; 3828 if (!closing) { 3829 if (atomic_read(&po->mapped)) 3830 goto out; 3831 if (packet_read_pending(rb)) 3832 goto out; 3833 } 3834 3835 if (req->tp_block_nr) { 3836 /* Sanity tests and some calculations */ 3837 err = -EBUSY; 3838 if (unlikely(rb->pg_vec)) 3839 goto out; 3840 3841 switch (po->tp_version) { 3842 case TPACKET_V1: 3843 po->tp_hdrlen = TPACKET_HDRLEN; 3844 break; 3845 case TPACKET_V2: 3846 po->tp_hdrlen = TPACKET2_HDRLEN; 3847 break; 3848 case TPACKET_V3: 3849 po->tp_hdrlen = TPACKET3_HDRLEN; 3850 break; 3851 } 3852 3853 err = -EINVAL; 3854 if (unlikely((int)req->tp_block_size <= 0)) 3855 goto out; 3856 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1))) 3857 goto out; 3858 if (po->tp_version >= TPACKET_V3 && 3859 (int)(req->tp_block_size - 3860 BLK_PLUS_PRIV(req_u->req3.tp_sizeof_priv)) <= 0) 3861 goto out; 3862 if (unlikely(req->tp_frame_size < po->tp_hdrlen + 3863 po->tp_reserve)) 3864 goto out; 3865 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1))) 3866 goto out; 3867 3868 rb->frames_per_block = req->tp_block_size/req->tp_frame_size; 3869 if (unlikely(rb->frames_per_block <= 0)) 3870 goto out; 3871 if (unlikely((rb->frames_per_block * req->tp_block_nr) != 3872 req->tp_frame_nr)) 3873 goto out; 3874 3875 err = -ENOMEM; 3876 order = get_order(req->tp_block_size); 3877 pg_vec = alloc_pg_vec(req, order); 3878 if (unlikely(!pg_vec)) 3879 goto out; 3880 switch (po->tp_version) { 3881 case TPACKET_V3: 3882 /* Transmit path is not supported. We checked 3883 * it above but just being paranoid 3884 */ 3885 if (!tx_ring) 3886 init_prb_bdqc(po, rb, pg_vec, req_u, tx_ring); 3887 break; 3888 default: 3889 break; 3890 } 3891 } 3892 /* Done */ 3893 else { 3894 err = -EINVAL; 3895 if (unlikely(req->tp_frame_nr)) 3896 goto out; 3897 } 3898 3899 lock_sock(sk); 3900 3901 /* Detach socket from network */ 3902 spin_lock(&po->bind_lock); 3903 was_running = po->running; 3904 num = po->num; 3905 if (was_running) { 3906 po->num = 0; 3907 __unregister_prot_hook(sk, false); 3908 } 3909 spin_unlock(&po->bind_lock); 3910 3911 synchronize_net(); 3912 3913 err = -EBUSY; 3914 mutex_lock(&po->pg_vec_lock); 3915 if (closing || atomic_read(&po->mapped) == 0) { 3916 err = 0; 3917 spin_lock_bh(&rb_queue->lock); 3918 swap(rb->pg_vec, pg_vec); 3919 rb->frame_max = (req->tp_frame_nr - 1); 3920 rb->head = 0; 3921 rb->frame_size = req->tp_frame_size; 3922 spin_unlock_bh(&rb_queue->lock); 3923 3924 swap(rb->pg_vec_order, order); 3925 swap(rb->pg_vec_len, req->tp_block_nr); 3926 3927 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE; 3928 po->prot_hook.func = (po->rx_ring.pg_vec) ? 3929 tpacket_rcv : packet_rcv; 3930 skb_queue_purge(rb_queue); 3931 if (atomic_read(&po->mapped)) 3932 pr_err("packet_mmap: vma is busy: %d\n", 3933 atomic_read(&po->mapped)); 3934 } 3935 mutex_unlock(&po->pg_vec_lock); 3936 3937 spin_lock(&po->bind_lock); 3938 if (was_running) { 3939 po->num = num; 3940 register_prot_hook(sk); 3941 } 3942 spin_unlock(&po->bind_lock); 3943 if (closing && (po->tp_version > TPACKET_V2)) { 3944 /* Because we don't support block-based V3 on tx-ring */ 3945 if (!tx_ring) 3946 prb_shutdown_retire_blk_timer(po, tx_ring, rb_queue); 3947 } 3948 release_sock(sk); 3949 3950 if (pg_vec) 3951 free_pg_vec(pg_vec, order, req->tp_block_nr); 3952 out: 3953 return err; 3954 } 3955 3956 static int packet_mmap(struct file *file, struct socket *sock, 3957 struct vm_area_struct *vma) 3958 { 3959 struct sock *sk = sock->sk; 3960 struct packet_sock *po = pkt_sk(sk); 3961 unsigned long size, expected_size; 3962 struct packet_ring_buffer *rb; 3963 unsigned long start; 3964 int err = -EINVAL; 3965 int i; 3966 3967 if (vma->vm_pgoff) 3968 return -EINVAL; 3969 3970 mutex_lock(&po->pg_vec_lock); 3971 3972 expected_size = 0; 3973 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) { 3974 if (rb->pg_vec) { 3975 expected_size += rb->pg_vec_len 3976 * rb->pg_vec_pages 3977 * PAGE_SIZE; 3978 } 3979 } 3980 3981 if (expected_size == 0) 3982 goto out; 3983 3984 size = vma->vm_end - vma->vm_start; 3985 if (size != expected_size) 3986 goto out; 3987 3988 start = vma->vm_start; 3989 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) { 3990 if (rb->pg_vec == NULL) 3991 continue; 3992 3993 for (i = 0; i < rb->pg_vec_len; i++) { 3994 struct page *page; 3995 void *kaddr = rb->pg_vec[i].buffer; 3996 int pg_num; 3997 3998 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) { 3999 page = pgv_to_page(kaddr); 4000 err = vm_insert_page(vma, start, page); 4001 if (unlikely(err)) 4002 goto out; 4003 start += PAGE_SIZE; 4004 kaddr += PAGE_SIZE; 4005 } 4006 } 4007 } 4008 4009 atomic_inc(&po->mapped); 4010 vma->vm_ops = &packet_mmap_ops; 4011 err = 0; 4012 4013 out: 4014 mutex_unlock(&po->pg_vec_lock); 4015 return err; 4016 } 4017 4018 static const struct proto_ops packet_ops_spkt = { 4019 .family = PF_PACKET, 4020 .owner = THIS_MODULE, 4021 .release = packet_release, 4022 .bind = packet_bind_spkt, 4023 .connect = sock_no_connect, 4024 .socketpair = sock_no_socketpair, 4025 .accept = sock_no_accept, 4026 .getname = packet_getname_spkt, 4027 .poll = datagram_poll, 4028 .ioctl = packet_ioctl, 4029 .listen = sock_no_listen, 4030 .shutdown = sock_no_shutdown, 4031 .setsockopt = sock_no_setsockopt, 4032 .getsockopt = sock_no_getsockopt, 4033 .sendmsg = packet_sendmsg_spkt, 4034 .recvmsg = packet_recvmsg, 4035 .mmap = sock_no_mmap, 4036 .sendpage = sock_no_sendpage, 4037 }; 4038 4039 static const struct proto_ops packet_ops = { 4040 .family = PF_PACKET, 4041 .owner = THIS_MODULE, 4042 .release = packet_release, 4043 .bind = packet_bind, 4044 .connect = sock_no_connect, 4045 .socketpair = sock_no_socketpair, 4046 .accept = sock_no_accept, 4047 .getname = packet_getname, 4048 .poll = packet_poll, 4049 .ioctl = packet_ioctl, 4050 .listen = sock_no_listen, 4051 .shutdown = sock_no_shutdown, 4052 .setsockopt = packet_setsockopt, 4053 .getsockopt = packet_getsockopt, 4054 .sendmsg = packet_sendmsg, 4055 .recvmsg = packet_recvmsg, 4056 .mmap = packet_mmap, 4057 .sendpage = sock_no_sendpage, 4058 }; 4059 4060 static const struct net_proto_family packet_family_ops = { 4061 .family = PF_PACKET, 4062 .create = packet_create, 4063 .owner = THIS_MODULE, 4064 }; 4065 4066 static struct notifier_block packet_netdev_notifier = { 4067 .notifier_call = packet_notifier, 4068 }; 4069 4070 #ifdef CONFIG_PROC_FS 4071 4072 static void *packet_seq_start(struct seq_file *seq, loff_t *pos) 4073 __acquires(RCU) 4074 { 4075 struct net *net = seq_file_net(seq); 4076 4077 rcu_read_lock(); 4078 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos); 4079 } 4080 4081 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos) 4082 { 4083 struct net *net = seq_file_net(seq); 4084 return seq_hlist_next_rcu(v, &net->packet.sklist, pos); 4085 } 4086 4087 static void packet_seq_stop(struct seq_file *seq, void *v) 4088 __releases(RCU) 4089 { 4090 rcu_read_unlock(); 4091 } 4092 4093 static int packet_seq_show(struct seq_file *seq, void *v) 4094 { 4095 if (v == SEQ_START_TOKEN) 4096 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n"); 4097 else { 4098 struct sock *s = sk_entry(v); 4099 const struct packet_sock *po = pkt_sk(s); 4100 4101 seq_printf(seq, 4102 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n", 4103 s, 4104 atomic_read(&s->sk_refcnt), 4105 s->sk_type, 4106 ntohs(po->num), 4107 po->ifindex, 4108 po->running, 4109 atomic_read(&s->sk_rmem_alloc), 4110 from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)), 4111 sock_i_ino(s)); 4112 } 4113 4114 return 0; 4115 } 4116 4117 static const struct seq_operations packet_seq_ops = { 4118 .start = packet_seq_start, 4119 .next = packet_seq_next, 4120 .stop = packet_seq_stop, 4121 .show = packet_seq_show, 4122 }; 4123 4124 static int packet_seq_open(struct inode *inode, struct file *file) 4125 { 4126 return seq_open_net(inode, file, &packet_seq_ops, 4127 sizeof(struct seq_net_private)); 4128 } 4129 4130 static const struct file_operations packet_seq_fops = { 4131 .owner = THIS_MODULE, 4132 .open = packet_seq_open, 4133 .read = seq_read, 4134 .llseek = seq_lseek, 4135 .release = seq_release_net, 4136 }; 4137 4138 #endif 4139 4140 static int __net_init packet_net_init(struct net *net) 4141 { 4142 mutex_init(&net->packet.sklist_lock); 4143 INIT_HLIST_HEAD(&net->packet.sklist); 4144 4145 if (!proc_create("packet", 0, net->proc_net, &packet_seq_fops)) 4146 return -ENOMEM; 4147 4148 return 0; 4149 } 4150 4151 static void __net_exit packet_net_exit(struct net *net) 4152 { 4153 remove_proc_entry("packet", net->proc_net); 4154 } 4155 4156 static struct pernet_operations packet_net_ops = { 4157 .init = packet_net_init, 4158 .exit = packet_net_exit, 4159 }; 4160 4161 4162 static void __exit packet_exit(void) 4163 { 4164 unregister_netdevice_notifier(&packet_netdev_notifier); 4165 unregister_pernet_subsys(&packet_net_ops); 4166 sock_unregister(PF_PACKET); 4167 proto_unregister(&packet_proto); 4168 } 4169 4170 static int __init packet_init(void) 4171 { 4172 int rc = proto_register(&packet_proto, 0); 4173 4174 if (rc != 0) 4175 goto out; 4176 4177 sock_register(&packet_family_ops); 4178 register_pernet_subsys(&packet_net_ops); 4179 register_netdevice_notifier(&packet_netdev_notifier); 4180 out: 4181 return rc; 4182 } 4183 4184 module_init(packet_init); 4185 module_exit(packet_exit); 4186 MODULE_LICENSE("GPL"); 4187 MODULE_ALIAS_NETPROTO(PF_PACKET); 4188