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) 547 { 548 struct tpacket_kbdq_core *pkc; 549 550 pkc = GET_PBDQC_FROM_RB(&po->rx_ring); 551 prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired); 552 } 553 554 static int prb_calc_retire_blk_tmo(struct packet_sock *po, 555 int blk_size_in_bytes) 556 { 557 struct net_device *dev; 558 unsigned int mbits = 0, msec = 0, div = 0, tmo = 0; 559 struct ethtool_cmd ecmd; 560 int err; 561 u32 speed; 562 563 rtnl_lock(); 564 dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex); 565 if (unlikely(!dev)) { 566 rtnl_unlock(); 567 return DEFAULT_PRB_RETIRE_TOV; 568 } 569 err = __ethtool_get_settings(dev, &ecmd); 570 speed = ethtool_cmd_speed(&ecmd); 571 rtnl_unlock(); 572 if (!err) { 573 /* 574 * If the link speed is so slow you don't really 575 * need to worry about perf anyways 576 */ 577 if (speed < SPEED_1000 || speed == SPEED_UNKNOWN) { 578 return DEFAULT_PRB_RETIRE_TOV; 579 } else { 580 msec = 1; 581 div = speed / 1000; 582 } 583 } 584 585 mbits = (blk_size_in_bytes * 8) / (1024 * 1024); 586 587 if (div) 588 mbits /= div; 589 590 tmo = mbits * msec; 591 592 if (div) 593 return tmo+1; 594 return tmo; 595 } 596 597 static void prb_init_ft_ops(struct tpacket_kbdq_core *p1, 598 union tpacket_req_u *req_u) 599 { 600 p1->feature_req_word = req_u->req3.tp_feature_req_word; 601 } 602 603 static void init_prb_bdqc(struct packet_sock *po, 604 struct packet_ring_buffer *rb, 605 struct pgv *pg_vec, 606 union tpacket_req_u *req_u) 607 { 608 struct tpacket_kbdq_core *p1 = GET_PBDQC_FROM_RB(rb); 609 struct tpacket_block_desc *pbd; 610 611 memset(p1, 0x0, sizeof(*p1)); 612 613 p1->knxt_seq_num = 1; 614 p1->pkbdq = pg_vec; 615 pbd = (struct tpacket_block_desc *)pg_vec[0].buffer; 616 p1->pkblk_start = pg_vec[0].buffer; 617 p1->kblk_size = req_u->req3.tp_block_size; 618 p1->knum_blocks = req_u->req3.tp_block_nr; 619 p1->hdrlen = po->tp_hdrlen; 620 p1->version = po->tp_version; 621 p1->last_kactive_blk_num = 0; 622 po->stats.stats3.tp_freeze_q_cnt = 0; 623 if (req_u->req3.tp_retire_blk_tov) 624 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov; 625 else 626 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po, 627 req_u->req3.tp_block_size); 628 p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov); 629 p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv; 630 631 p1->max_frame_len = p1->kblk_size - BLK_PLUS_PRIV(p1->blk_sizeof_priv); 632 prb_init_ft_ops(p1, req_u); 633 prb_setup_retire_blk_timer(po); 634 prb_open_block(p1, pbd); 635 } 636 637 /* Do NOT update the last_blk_num first. 638 * Assumes sk_buff_head lock is held. 639 */ 640 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc) 641 { 642 mod_timer(&pkc->retire_blk_timer, 643 jiffies + pkc->tov_in_jiffies); 644 pkc->last_kactive_blk_num = pkc->kactive_blk_num; 645 } 646 647 /* 648 * Timer logic: 649 * 1) We refresh the timer only when we open a block. 650 * By doing this we don't waste cycles refreshing the timer 651 * on packet-by-packet basis. 652 * 653 * With a 1MB block-size, on a 1Gbps line, it will take 654 * i) ~8 ms to fill a block + ii) memcpy etc. 655 * In this cut we are not accounting for the memcpy time. 656 * 657 * So, if the user sets the 'tmo' to 10ms then the timer 658 * will never fire while the block is still getting filled 659 * (which is what we want). However, the user could choose 660 * to close a block early and that's fine. 661 * 662 * But when the timer does fire, we check whether or not to refresh it. 663 * Since the tmo granularity is in msecs, it is not too expensive 664 * to refresh the timer, lets say every '8' msecs. 665 * Either the user can set the 'tmo' or we can derive it based on 666 * a) line-speed and b) block-size. 667 * prb_calc_retire_blk_tmo() calculates the tmo. 668 * 669 */ 670 static void prb_retire_rx_blk_timer_expired(unsigned long data) 671 { 672 struct packet_sock *po = (struct packet_sock *)data; 673 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(&po->rx_ring); 674 unsigned int frozen; 675 struct tpacket_block_desc *pbd; 676 677 spin_lock(&po->sk.sk_receive_queue.lock); 678 679 frozen = prb_queue_frozen(pkc); 680 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc); 681 682 if (unlikely(pkc->delete_blk_timer)) 683 goto out; 684 685 /* We only need to plug the race when the block is partially filled. 686 * tpacket_rcv: 687 * lock(); increment BLOCK_NUM_PKTS; unlock() 688 * copy_bits() is in progress ... 689 * timer fires on other cpu: 690 * we can't retire the current block because copy_bits 691 * is in progress. 692 * 693 */ 694 if (BLOCK_NUM_PKTS(pbd)) { 695 while (atomic_read(&pkc->blk_fill_in_prog)) { 696 /* Waiting for skb_copy_bits to finish... */ 697 cpu_relax(); 698 } 699 } 700 701 if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) { 702 if (!frozen) { 703 if (!BLOCK_NUM_PKTS(pbd)) { 704 /* An empty block. Just refresh the timer. */ 705 goto refresh_timer; 706 } 707 prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO); 708 if (!prb_dispatch_next_block(pkc, po)) 709 goto refresh_timer; 710 else 711 goto out; 712 } else { 713 /* Case 1. Queue was frozen because user-space was 714 * lagging behind. 715 */ 716 if (prb_curr_blk_in_use(pkc, pbd)) { 717 /* 718 * Ok, user-space is still behind. 719 * So just refresh the timer. 720 */ 721 goto refresh_timer; 722 } else { 723 /* Case 2. queue was frozen,user-space caught up, 724 * now the link went idle && the timer fired. 725 * We don't have a block to close.So we open this 726 * block and restart the timer. 727 * opening a block thaws the queue,restarts timer 728 * Thawing/timer-refresh is a side effect. 729 */ 730 prb_open_block(pkc, pbd); 731 goto out; 732 } 733 } 734 } 735 736 refresh_timer: 737 _prb_refresh_rx_retire_blk_timer(pkc); 738 739 out: 740 spin_unlock(&po->sk.sk_receive_queue.lock); 741 } 742 743 static void prb_flush_block(struct tpacket_kbdq_core *pkc1, 744 struct tpacket_block_desc *pbd1, __u32 status) 745 { 746 /* Flush everything minus the block header */ 747 748 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1 749 u8 *start, *end; 750 751 start = (u8 *)pbd1; 752 753 /* Skip the block header(we know header WILL fit in 4K) */ 754 start += PAGE_SIZE; 755 756 end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end); 757 for (; start < end; start += PAGE_SIZE) 758 flush_dcache_page(pgv_to_page(start)); 759 760 smp_wmb(); 761 #endif 762 763 /* Now update the block status. */ 764 765 BLOCK_STATUS(pbd1) = status; 766 767 /* Flush the block header */ 768 769 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1 770 start = (u8 *)pbd1; 771 flush_dcache_page(pgv_to_page(start)); 772 773 smp_wmb(); 774 #endif 775 } 776 777 /* 778 * Side effect: 779 * 780 * 1) flush the block 781 * 2) Increment active_blk_num 782 * 783 * Note:We DONT refresh the timer on purpose. 784 * Because almost always the next block will be opened. 785 */ 786 static void prb_close_block(struct tpacket_kbdq_core *pkc1, 787 struct tpacket_block_desc *pbd1, 788 struct packet_sock *po, unsigned int stat) 789 { 790 __u32 status = TP_STATUS_USER | stat; 791 792 struct tpacket3_hdr *last_pkt; 793 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1; 794 struct sock *sk = &po->sk; 795 796 if (po->stats.stats3.tp_drops) 797 status |= TP_STATUS_LOSING; 798 799 last_pkt = (struct tpacket3_hdr *)pkc1->prev; 800 last_pkt->tp_next_offset = 0; 801 802 /* Get the ts of the last pkt */ 803 if (BLOCK_NUM_PKTS(pbd1)) { 804 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec; 805 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec; 806 } else { 807 /* Ok, we tmo'd - so get the current time. 808 * 809 * It shouldn't really happen as we don't close empty 810 * blocks. See prb_retire_rx_blk_timer_expired(). 811 */ 812 struct timespec ts; 813 getnstimeofday(&ts); 814 h1->ts_last_pkt.ts_sec = ts.tv_sec; 815 h1->ts_last_pkt.ts_nsec = ts.tv_nsec; 816 } 817 818 smp_wmb(); 819 820 /* Flush the block */ 821 prb_flush_block(pkc1, pbd1, status); 822 823 sk->sk_data_ready(sk); 824 825 pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1); 826 } 827 828 static void prb_thaw_queue(struct tpacket_kbdq_core *pkc) 829 { 830 pkc->reset_pending_on_curr_blk = 0; 831 } 832 833 /* 834 * Side effect of opening a block: 835 * 836 * 1) prb_queue is thawed. 837 * 2) retire_blk_timer is refreshed. 838 * 839 */ 840 static void prb_open_block(struct tpacket_kbdq_core *pkc1, 841 struct tpacket_block_desc *pbd1) 842 { 843 struct timespec ts; 844 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1; 845 846 smp_rmb(); 847 848 /* We could have just memset this but we will lose the 849 * flexibility of making the priv area sticky 850 */ 851 852 BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++; 853 BLOCK_NUM_PKTS(pbd1) = 0; 854 BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv); 855 856 getnstimeofday(&ts); 857 858 h1->ts_first_pkt.ts_sec = ts.tv_sec; 859 h1->ts_first_pkt.ts_nsec = ts.tv_nsec; 860 861 pkc1->pkblk_start = (char *)pbd1; 862 pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv); 863 864 BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv); 865 BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN; 866 867 pbd1->version = pkc1->version; 868 pkc1->prev = pkc1->nxt_offset; 869 pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size; 870 871 prb_thaw_queue(pkc1); 872 _prb_refresh_rx_retire_blk_timer(pkc1); 873 874 smp_wmb(); 875 } 876 877 /* 878 * Queue freeze logic: 879 * 1) Assume tp_block_nr = 8 blocks. 880 * 2) At time 't0', user opens Rx ring. 881 * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7 882 * 4) user-space is either sleeping or processing block '0'. 883 * 5) tpacket_rcv is currently filling block '7', since there is no space left, 884 * it will close block-7,loop around and try to fill block '0'. 885 * call-flow: 886 * __packet_lookup_frame_in_block 887 * prb_retire_current_block() 888 * prb_dispatch_next_block() 889 * |->(BLOCK_STATUS == USER) evaluates to true 890 * 5.1) Since block-0 is currently in-use, we just freeze the queue. 891 * 6) Now there are two cases: 892 * 6.1) Link goes idle right after the queue is frozen. 893 * But remember, the last open_block() refreshed the timer. 894 * When this timer expires,it will refresh itself so that we can 895 * re-open block-0 in near future. 896 * 6.2) Link is busy and keeps on receiving packets. This is a simple 897 * case and __packet_lookup_frame_in_block will check if block-0 898 * is free and can now be re-used. 899 */ 900 static void prb_freeze_queue(struct tpacket_kbdq_core *pkc, 901 struct packet_sock *po) 902 { 903 pkc->reset_pending_on_curr_blk = 1; 904 po->stats.stats3.tp_freeze_q_cnt++; 905 } 906 907 #define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT)) 908 909 /* 910 * If the next block is free then we will dispatch it 911 * and return a good offset. 912 * Else, we will freeze the queue. 913 * So, caller must check the return value. 914 */ 915 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc, 916 struct packet_sock *po) 917 { 918 struct tpacket_block_desc *pbd; 919 920 smp_rmb(); 921 922 /* 1. Get current block num */ 923 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc); 924 925 /* 2. If this block is currently in_use then freeze the queue */ 926 if (TP_STATUS_USER & BLOCK_STATUS(pbd)) { 927 prb_freeze_queue(pkc, po); 928 return NULL; 929 } 930 931 /* 932 * 3. 933 * open this block and return the offset where the first packet 934 * needs to get stored. 935 */ 936 prb_open_block(pkc, pbd); 937 return (void *)pkc->nxt_offset; 938 } 939 940 static void prb_retire_current_block(struct tpacket_kbdq_core *pkc, 941 struct packet_sock *po, unsigned int status) 942 { 943 struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc); 944 945 /* retire/close the current block */ 946 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) { 947 /* 948 * Plug the case where copy_bits() is in progress on 949 * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't 950 * have space to copy the pkt in the current block and 951 * called prb_retire_current_block() 952 * 953 * We don't need to worry about the TMO case because 954 * the timer-handler already handled this case. 955 */ 956 if (!(status & TP_STATUS_BLK_TMO)) { 957 while (atomic_read(&pkc->blk_fill_in_prog)) { 958 /* Waiting for skb_copy_bits to finish... */ 959 cpu_relax(); 960 } 961 } 962 prb_close_block(pkc, pbd, po, status); 963 return; 964 } 965 } 966 967 static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc, 968 struct tpacket_block_desc *pbd) 969 { 970 return TP_STATUS_USER & BLOCK_STATUS(pbd); 971 } 972 973 static int prb_queue_frozen(struct tpacket_kbdq_core *pkc) 974 { 975 return pkc->reset_pending_on_curr_blk; 976 } 977 978 static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb) 979 { 980 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb); 981 atomic_dec(&pkc->blk_fill_in_prog); 982 } 983 984 static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc, 985 struct tpacket3_hdr *ppd) 986 { 987 ppd->hv1.tp_rxhash = skb_get_hash(pkc->skb); 988 } 989 990 static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc, 991 struct tpacket3_hdr *ppd) 992 { 993 ppd->hv1.tp_rxhash = 0; 994 } 995 996 static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc, 997 struct tpacket3_hdr *ppd) 998 { 999 if (skb_vlan_tag_present(pkc->skb)) { 1000 ppd->hv1.tp_vlan_tci = skb_vlan_tag_get(pkc->skb); 1001 ppd->hv1.tp_vlan_tpid = ntohs(pkc->skb->vlan_proto); 1002 ppd->tp_status = TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID; 1003 } else { 1004 ppd->hv1.tp_vlan_tci = 0; 1005 ppd->hv1.tp_vlan_tpid = 0; 1006 ppd->tp_status = TP_STATUS_AVAILABLE; 1007 } 1008 } 1009 1010 static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc, 1011 struct tpacket3_hdr *ppd) 1012 { 1013 ppd->hv1.tp_padding = 0; 1014 prb_fill_vlan_info(pkc, ppd); 1015 1016 if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH) 1017 prb_fill_rxhash(pkc, ppd); 1018 else 1019 prb_clear_rxhash(pkc, ppd); 1020 } 1021 1022 static void prb_fill_curr_block(char *curr, 1023 struct tpacket_kbdq_core *pkc, 1024 struct tpacket_block_desc *pbd, 1025 unsigned int len) 1026 { 1027 struct tpacket3_hdr *ppd; 1028 1029 ppd = (struct tpacket3_hdr *)curr; 1030 ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len); 1031 pkc->prev = curr; 1032 pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len); 1033 BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len); 1034 BLOCK_NUM_PKTS(pbd) += 1; 1035 atomic_inc(&pkc->blk_fill_in_prog); 1036 prb_run_all_ft_ops(pkc, ppd); 1037 } 1038 1039 /* Assumes caller has the sk->rx_queue.lock */ 1040 static void *__packet_lookup_frame_in_block(struct packet_sock *po, 1041 struct sk_buff *skb, 1042 int status, 1043 unsigned int len 1044 ) 1045 { 1046 struct tpacket_kbdq_core *pkc; 1047 struct tpacket_block_desc *pbd; 1048 char *curr, *end; 1049 1050 pkc = GET_PBDQC_FROM_RB(&po->rx_ring); 1051 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc); 1052 1053 /* Queue is frozen when user space is lagging behind */ 1054 if (prb_queue_frozen(pkc)) { 1055 /* 1056 * Check if that last block which caused the queue to freeze, 1057 * is still in_use by user-space. 1058 */ 1059 if (prb_curr_blk_in_use(pkc, pbd)) { 1060 /* Can't record this packet */ 1061 return NULL; 1062 } else { 1063 /* 1064 * Ok, the block was released by user-space. 1065 * Now let's open that block. 1066 * opening a block also thaws the queue. 1067 * Thawing is a side effect. 1068 */ 1069 prb_open_block(pkc, pbd); 1070 } 1071 } 1072 1073 smp_mb(); 1074 curr = pkc->nxt_offset; 1075 pkc->skb = skb; 1076 end = (char *)pbd + pkc->kblk_size; 1077 1078 /* first try the current block */ 1079 if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) { 1080 prb_fill_curr_block(curr, pkc, pbd, len); 1081 return (void *)curr; 1082 } 1083 1084 /* Ok, close the current block */ 1085 prb_retire_current_block(pkc, po, 0); 1086 1087 /* Now, try to dispatch the next block */ 1088 curr = (char *)prb_dispatch_next_block(pkc, po); 1089 if (curr) { 1090 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc); 1091 prb_fill_curr_block(curr, pkc, pbd, len); 1092 return (void *)curr; 1093 } 1094 1095 /* 1096 * No free blocks are available.user_space hasn't caught up yet. 1097 * Queue was just frozen and now this packet will get dropped. 1098 */ 1099 return NULL; 1100 } 1101 1102 static void *packet_current_rx_frame(struct packet_sock *po, 1103 struct sk_buff *skb, 1104 int status, unsigned int len) 1105 { 1106 char *curr = NULL; 1107 switch (po->tp_version) { 1108 case TPACKET_V1: 1109 case TPACKET_V2: 1110 curr = packet_lookup_frame(po, &po->rx_ring, 1111 po->rx_ring.head, status); 1112 return curr; 1113 case TPACKET_V3: 1114 return __packet_lookup_frame_in_block(po, skb, status, len); 1115 default: 1116 WARN(1, "TPACKET version not supported\n"); 1117 BUG(); 1118 return NULL; 1119 } 1120 } 1121 1122 static void *prb_lookup_block(struct packet_sock *po, 1123 struct packet_ring_buffer *rb, 1124 unsigned int idx, 1125 int status) 1126 { 1127 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb); 1128 struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, idx); 1129 1130 if (status != BLOCK_STATUS(pbd)) 1131 return NULL; 1132 return pbd; 1133 } 1134 1135 static int prb_previous_blk_num(struct packet_ring_buffer *rb) 1136 { 1137 unsigned int prev; 1138 if (rb->prb_bdqc.kactive_blk_num) 1139 prev = rb->prb_bdqc.kactive_blk_num-1; 1140 else 1141 prev = rb->prb_bdqc.knum_blocks-1; 1142 return prev; 1143 } 1144 1145 /* Assumes caller has held the rx_queue.lock */ 1146 static void *__prb_previous_block(struct packet_sock *po, 1147 struct packet_ring_buffer *rb, 1148 int status) 1149 { 1150 unsigned int previous = prb_previous_blk_num(rb); 1151 return prb_lookup_block(po, rb, previous, status); 1152 } 1153 1154 static void *packet_previous_rx_frame(struct packet_sock *po, 1155 struct packet_ring_buffer *rb, 1156 int status) 1157 { 1158 if (po->tp_version <= TPACKET_V2) 1159 return packet_previous_frame(po, rb, status); 1160 1161 return __prb_previous_block(po, rb, status); 1162 } 1163 1164 static void packet_increment_rx_head(struct packet_sock *po, 1165 struct packet_ring_buffer *rb) 1166 { 1167 switch (po->tp_version) { 1168 case TPACKET_V1: 1169 case TPACKET_V2: 1170 return packet_increment_head(rb); 1171 case TPACKET_V3: 1172 default: 1173 WARN(1, "TPACKET version not supported.\n"); 1174 BUG(); 1175 return; 1176 } 1177 } 1178 1179 static void *packet_previous_frame(struct packet_sock *po, 1180 struct packet_ring_buffer *rb, 1181 int status) 1182 { 1183 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max; 1184 return packet_lookup_frame(po, rb, previous, status); 1185 } 1186 1187 static void packet_increment_head(struct packet_ring_buffer *buff) 1188 { 1189 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0; 1190 } 1191 1192 static void packet_inc_pending(struct packet_ring_buffer *rb) 1193 { 1194 this_cpu_inc(*rb->pending_refcnt); 1195 } 1196 1197 static void packet_dec_pending(struct packet_ring_buffer *rb) 1198 { 1199 this_cpu_dec(*rb->pending_refcnt); 1200 } 1201 1202 static unsigned int packet_read_pending(const struct packet_ring_buffer *rb) 1203 { 1204 unsigned int refcnt = 0; 1205 int cpu; 1206 1207 /* We don't use pending refcount in rx_ring. */ 1208 if (rb->pending_refcnt == NULL) 1209 return 0; 1210 1211 for_each_possible_cpu(cpu) 1212 refcnt += *per_cpu_ptr(rb->pending_refcnt, cpu); 1213 1214 return refcnt; 1215 } 1216 1217 static int packet_alloc_pending(struct packet_sock *po) 1218 { 1219 po->rx_ring.pending_refcnt = NULL; 1220 1221 po->tx_ring.pending_refcnt = alloc_percpu(unsigned int); 1222 if (unlikely(po->tx_ring.pending_refcnt == NULL)) 1223 return -ENOBUFS; 1224 1225 return 0; 1226 } 1227 1228 static void packet_free_pending(struct packet_sock *po) 1229 { 1230 free_percpu(po->tx_ring.pending_refcnt); 1231 } 1232 1233 #define ROOM_POW_OFF 2 1234 #define ROOM_NONE 0x0 1235 #define ROOM_LOW 0x1 1236 #define ROOM_NORMAL 0x2 1237 1238 static bool __tpacket_has_room(struct packet_sock *po, int pow_off) 1239 { 1240 int idx, len; 1241 1242 len = po->rx_ring.frame_max + 1; 1243 idx = po->rx_ring.head; 1244 if (pow_off) 1245 idx += len >> pow_off; 1246 if (idx >= len) 1247 idx -= len; 1248 return packet_lookup_frame(po, &po->rx_ring, idx, TP_STATUS_KERNEL); 1249 } 1250 1251 static bool __tpacket_v3_has_room(struct packet_sock *po, int pow_off) 1252 { 1253 int idx, len; 1254 1255 len = po->rx_ring.prb_bdqc.knum_blocks; 1256 idx = po->rx_ring.prb_bdqc.kactive_blk_num; 1257 if (pow_off) 1258 idx += len >> pow_off; 1259 if (idx >= len) 1260 idx -= len; 1261 return prb_lookup_block(po, &po->rx_ring, idx, TP_STATUS_KERNEL); 1262 } 1263 1264 static int __packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb) 1265 { 1266 struct sock *sk = &po->sk; 1267 int ret = ROOM_NONE; 1268 1269 if (po->prot_hook.func != tpacket_rcv) { 1270 int avail = sk->sk_rcvbuf - atomic_read(&sk->sk_rmem_alloc) 1271 - (skb ? skb->truesize : 0); 1272 if (avail > (sk->sk_rcvbuf >> ROOM_POW_OFF)) 1273 return ROOM_NORMAL; 1274 else if (avail > 0) 1275 return ROOM_LOW; 1276 else 1277 return ROOM_NONE; 1278 } 1279 1280 if (po->tp_version == TPACKET_V3) { 1281 if (__tpacket_v3_has_room(po, ROOM_POW_OFF)) 1282 ret = ROOM_NORMAL; 1283 else if (__tpacket_v3_has_room(po, 0)) 1284 ret = ROOM_LOW; 1285 } else { 1286 if (__tpacket_has_room(po, ROOM_POW_OFF)) 1287 ret = ROOM_NORMAL; 1288 else if (__tpacket_has_room(po, 0)) 1289 ret = ROOM_LOW; 1290 } 1291 1292 return ret; 1293 } 1294 1295 static int packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb) 1296 { 1297 int ret; 1298 bool has_room; 1299 1300 spin_lock_bh(&po->sk.sk_receive_queue.lock); 1301 ret = __packet_rcv_has_room(po, skb); 1302 has_room = ret == ROOM_NORMAL; 1303 if (po->pressure == has_room) 1304 po->pressure = !has_room; 1305 spin_unlock_bh(&po->sk.sk_receive_queue.lock); 1306 1307 return ret; 1308 } 1309 1310 static void packet_sock_destruct(struct sock *sk) 1311 { 1312 skb_queue_purge(&sk->sk_error_queue); 1313 1314 WARN_ON(atomic_read(&sk->sk_rmem_alloc)); 1315 WARN_ON(atomic_read(&sk->sk_wmem_alloc)); 1316 1317 if (!sock_flag(sk, SOCK_DEAD)) { 1318 pr_err("Attempt to release alive packet socket: %p\n", sk); 1319 return; 1320 } 1321 1322 sk_refcnt_debug_dec(sk); 1323 } 1324 1325 static bool fanout_flow_is_huge(struct packet_sock *po, struct sk_buff *skb) 1326 { 1327 u32 rxhash; 1328 int i, count = 0; 1329 1330 rxhash = skb_get_hash(skb); 1331 for (i = 0; i < ROLLOVER_HLEN; i++) 1332 if (po->rollover->history[i] == rxhash) 1333 count++; 1334 1335 po->rollover->history[prandom_u32() % ROLLOVER_HLEN] = rxhash; 1336 return count > (ROLLOVER_HLEN >> 1); 1337 } 1338 1339 static unsigned int fanout_demux_hash(struct packet_fanout *f, 1340 struct sk_buff *skb, 1341 unsigned int num) 1342 { 1343 return reciprocal_scale(skb_get_hash(skb), num); 1344 } 1345 1346 static unsigned int fanout_demux_lb(struct packet_fanout *f, 1347 struct sk_buff *skb, 1348 unsigned int num) 1349 { 1350 unsigned int val = atomic_inc_return(&f->rr_cur); 1351 1352 return val % num; 1353 } 1354 1355 static unsigned int fanout_demux_cpu(struct packet_fanout *f, 1356 struct sk_buff *skb, 1357 unsigned int num) 1358 { 1359 return smp_processor_id() % num; 1360 } 1361 1362 static unsigned int fanout_demux_rnd(struct packet_fanout *f, 1363 struct sk_buff *skb, 1364 unsigned int num) 1365 { 1366 return prandom_u32_max(num); 1367 } 1368 1369 static unsigned int fanout_demux_rollover(struct packet_fanout *f, 1370 struct sk_buff *skb, 1371 unsigned int idx, bool try_self, 1372 unsigned int num) 1373 { 1374 struct packet_sock *po, *po_next, *po_skip = NULL; 1375 unsigned int i, j, room = ROOM_NONE; 1376 1377 po = pkt_sk(f->arr[idx]); 1378 1379 if (try_self) { 1380 room = packet_rcv_has_room(po, skb); 1381 if (room == ROOM_NORMAL || 1382 (room == ROOM_LOW && !fanout_flow_is_huge(po, skb))) 1383 return idx; 1384 po_skip = po; 1385 } 1386 1387 i = j = min_t(int, po->rollover->sock, num - 1); 1388 do { 1389 po_next = pkt_sk(f->arr[i]); 1390 if (po_next != po_skip && !po_next->pressure && 1391 packet_rcv_has_room(po_next, skb) == ROOM_NORMAL) { 1392 if (i != j) 1393 po->rollover->sock = i; 1394 atomic_long_inc(&po->rollover->num); 1395 if (room == ROOM_LOW) 1396 atomic_long_inc(&po->rollover->num_huge); 1397 return i; 1398 } 1399 1400 if (++i == num) 1401 i = 0; 1402 } while (i != j); 1403 1404 atomic_long_inc(&po->rollover->num_failed); 1405 return idx; 1406 } 1407 1408 static unsigned int fanout_demux_qm(struct packet_fanout *f, 1409 struct sk_buff *skb, 1410 unsigned int num) 1411 { 1412 return skb_get_queue_mapping(skb) % num; 1413 } 1414 1415 static bool fanout_has_flag(struct packet_fanout *f, u16 flag) 1416 { 1417 return f->flags & (flag >> 8); 1418 } 1419 1420 static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev, 1421 struct packet_type *pt, struct net_device *orig_dev) 1422 { 1423 struct packet_fanout *f = pt->af_packet_priv; 1424 unsigned int num = READ_ONCE(f->num_members); 1425 struct packet_sock *po; 1426 unsigned int idx; 1427 1428 if (!net_eq(dev_net(dev), read_pnet(&f->net)) || 1429 !num) { 1430 kfree_skb(skb); 1431 return 0; 1432 } 1433 1434 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_DEFRAG)) { 1435 skb = ip_check_defrag(skb, IP_DEFRAG_AF_PACKET); 1436 if (!skb) 1437 return 0; 1438 } 1439 switch (f->type) { 1440 case PACKET_FANOUT_HASH: 1441 default: 1442 idx = fanout_demux_hash(f, skb, num); 1443 break; 1444 case PACKET_FANOUT_LB: 1445 idx = fanout_demux_lb(f, skb, num); 1446 break; 1447 case PACKET_FANOUT_CPU: 1448 idx = fanout_demux_cpu(f, skb, num); 1449 break; 1450 case PACKET_FANOUT_RND: 1451 idx = fanout_demux_rnd(f, skb, num); 1452 break; 1453 case PACKET_FANOUT_QM: 1454 idx = fanout_demux_qm(f, skb, num); 1455 break; 1456 case PACKET_FANOUT_ROLLOVER: 1457 idx = fanout_demux_rollover(f, skb, 0, false, num); 1458 break; 1459 } 1460 1461 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER)) 1462 idx = fanout_demux_rollover(f, skb, idx, true, num); 1463 1464 po = pkt_sk(f->arr[idx]); 1465 return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev); 1466 } 1467 1468 DEFINE_MUTEX(fanout_mutex); 1469 EXPORT_SYMBOL_GPL(fanout_mutex); 1470 static LIST_HEAD(fanout_list); 1471 1472 static void __fanout_link(struct sock *sk, struct packet_sock *po) 1473 { 1474 struct packet_fanout *f = po->fanout; 1475 1476 spin_lock(&f->lock); 1477 f->arr[f->num_members] = sk; 1478 smp_wmb(); 1479 f->num_members++; 1480 spin_unlock(&f->lock); 1481 } 1482 1483 static void __fanout_unlink(struct sock *sk, struct packet_sock *po) 1484 { 1485 struct packet_fanout *f = po->fanout; 1486 int i; 1487 1488 spin_lock(&f->lock); 1489 for (i = 0; i < f->num_members; i++) { 1490 if (f->arr[i] == sk) 1491 break; 1492 } 1493 BUG_ON(i >= f->num_members); 1494 f->arr[i] = f->arr[f->num_members - 1]; 1495 f->num_members--; 1496 spin_unlock(&f->lock); 1497 } 1498 1499 static bool match_fanout_group(struct packet_type *ptype, struct sock *sk) 1500 { 1501 if (ptype->af_packet_priv == (void *)((struct packet_sock *)sk)->fanout) 1502 return true; 1503 1504 return false; 1505 } 1506 1507 static int fanout_add(struct sock *sk, u16 id, u16 type_flags) 1508 { 1509 struct packet_sock *po = pkt_sk(sk); 1510 struct packet_fanout *f, *match; 1511 u8 type = type_flags & 0xff; 1512 u8 flags = type_flags >> 8; 1513 int err; 1514 1515 switch (type) { 1516 case PACKET_FANOUT_ROLLOVER: 1517 if (type_flags & PACKET_FANOUT_FLAG_ROLLOVER) 1518 return -EINVAL; 1519 case PACKET_FANOUT_HASH: 1520 case PACKET_FANOUT_LB: 1521 case PACKET_FANOUT_CPU: 1522 case PACKET_FANOUT_RND: 1523 case PACKET_FANOUT_QM: 1524 break; 1525 default: 1526 return -EINVAL; 1527 } 1528 1529 if (!po->running) 1530 return -EINVAL; 1531 1532 if (po->fanout) 1533 return -EALREADY; 1534 1535 if (type == PACKET_FANOUT_ROLLOVER || 1536 (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)) { 1537 po->rollover = kzalloc(sizeof(*po->rollover), GFP_KERNEL); 1538 if (!po->rollover) 1539 return -ENOMEM; 1540 atomic_long_set(&po->rollover->num, 0); 1541 atomic_long_set(&po->rollover->num_huge, 0); 1542 atomic_long_set(&po->rollover->num_failed, 0); 1543 } 1544 1545 mutex_lock(&fanout_mutex); 1546 match = NULL; 1547 list_for_each_entry(f, &fanout_list, list) { 1548 if (f->id == id && 1549 read_pnet(&f->net) == sock_net(sk)) { 1550 match = f; 1551 break; 1552 } 1553 } 1554 err = -EINVAL; 1555 if (match && match->flags != flags) 1556 goto out; 1557 if (!match) { 1558 err = -ENOMEM; 1559 match = kzalloc(sizeof(*match), GFP_KERNEL); 1560 if (!match) 1561 goto out; 1562 write_pnet(&match->net, sock_net(sk)); 1563 match->id = id; 1564 match->type = type; 1565 match->flags = flags; 1566 atomic_set(&match->rr_cur, 0); 1567 INIT_LIST_HEAD(&match->list); 1568 spin_lock_init(&match->lock); 1569 atomic_set(&match->sk_ref, 0); 1570 match->prot_hook.type = po->prot_hook.type; 1571 match->prot_hook.dev = po->prot_hook.dev; 1572 match->prot_hook.func = packet_rcv_fanout; 1573 match->prot_hook.af_packet_priv = match; 1574 match->prot_hook.id_match = match_fanout_group; 1575 dev_add_pack(&match->prot_hook); 1576 list_add(&match->list, &fanout_list); 1577 } 1578 err = -EINVAL; 1579 if (match->type == type && 1580 match->prot_hook.type == po->prot_hook.type && 1581 match->prot_hook.dev == po->prot_hook.dev) { 1582 err = -ENOSPC; 1583 if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) { 1584 __dev_remove_pack(&po->prot_hook); 1585 po->fanout = match; 1586 atomic_inc(&match->sk_ref); 1587 __fanout_link(sk, po); 1588 err = 0; 1589 } 1590 } 1591 out: 1592 mutex_unlock(&fanout_mutex); 1593 if (err) { 1594 kfree(po->rollover); 1595 po->rollover = NULL; 1596 } 1597 return err; 1598 } 1599 1600 static void fanout_release(struct sock *sk) 1601 { 1602 struct packet_sock *po = pkt_sk(sk); 1603 struct packet_fanout *f; 1604 1605 f = po->fanout; 1606 if (!f) 1607 return; 1608 1609 mutex_lock(&fanout_mutex); 1610 po->fanout = NULL; 1611 1612 if (atomic_dec_and_test(&f->sk_ref)) { 1613 list_del(&f->list); 1614 dev_remove_pack(&f->prot_hook); 1615 kfree(f); 1616 } 1617 mutex_unlock(&fanout_mutex); 1618 1619 if (po->rollover) 1620 kfree_rcu(po->rollover, rcu); 1621 } 1622 1623 static const struct proto_ops packet_ops; 1624 1625 static const struct proto_ops packet_ops_spkt; 1626 1627 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev, 1628 struct packet_type *pt, struct net_device *orig_dev) 1629 { 1630 struct sock *sk; 1631 struct sockaddr_pkt *spkt; 1632 1633 /* 1634 * When we registered the protocol we saved the socket in the data 1635 * field for just this event. 1636 */ 1637 1638 sk = pt->af_packet_priv; 1639 1640 /* 1641 * Yank back the headers [hope the device set this 1642 * right or kerboom...] 1643 * 1644 * Incoming packets have ll header pulled, 1645 * push it back. 1646 * 1647 * For outgoing ones skb->data == skb_mac_header(skb) 1648 * so that this procedure is noop. 1649 */ 1650 1651 if (skb->pkt_type == PACKET_LOOPBACK) 1652 goto out; 1653 1654 if (!net_eq(dev_net(dev), sock_net(sk))) 1655 goto out; 1656 1657 skb = skb_share_check(skb, GFP_ATOMIC); 1658 if (skb == NULL) 1659 goto oom; 1660 1661 /* drop any routing info */ 1662 skb_dst_drop(skb); 1663 1664 /* drop conntrack reference */ 1665 nf_reset(skb); 1666 1667 spkt = &PACKET_SKB_CB(skb)->sa.pkt; 1668 1669 skb_push(skb, skb->data - skb_mac_header(skb)); 1670 1671 /* 1672 * The SOCK_PACKET socket receives _all_ frames. 1673 */ 1674 1675 spkt->spkt_family = dev->type; 1676 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device)); 1677 spkt->spkt_protocol = skb->protocol; 1678 1679 /* 1680 * Charge the memory to the socket. This is done specifically 1681 * to prevent sockets using all the memory up. 1682 */ 1683 1684 if (sock_queue_rcv_skb(sk, skb) == 0) 1685 return 0; 1686 1687 out: 1688 kfree_skb(skb); 1689 oom: 1690 return 0; 1691 } 1692 1693 1694 /* 1695 * Output a raw packet to a device layer. This bypasses all the other 1696 * protocol layers and you must therefore supply it with a complete frame 1697 */ 1698 1699 static int packet_sendmsg_spkt(struct socket *sock, struct msghdr *msg, 1700 size_t len) 1701 { 1702 struct sock *sk = sock->sk; 1703 DECLARE_SOCKADDR(struct sockaddr_pkt *, saddr, msg->msg_name); 1704 struct sk_buff *skb = NULL; 1705 struct net_device *dev; 1706 __be16 proto = 0; 1707 int err; 1708 int extra_len = 0; 1709 1710 /* 1711 * Get and verify the address. 1712 */ 1713 1714 if (saddr) { 1715 if (msg->msg_namelen < sizeof(struct sockaddr)) 1716 return -EINVAL; 1717 if (msg->msg_namelen == sizeof(struct sockaddr_pkt)) 1718 proto = saddr->spkt_protocol; 1719 } else 1720 return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */ 1721 1722 /* 1723 * Find the device first to size check it 1724 */ 1725 1726 saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0; 1727 retry: 1728 rcu_read_lock(); 1729 dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device); 1730 err = -ENODEV; 1731 if (dev == NULL) 1732 goto out_unlock; 1733 1734 err = -ENETDOWN; 1735 if (!(dev->flags & IFF_UP)) 1736 goto out_unlock; 1737 1738 /* 1739 * You may not queue a frame bigger than the mtu. This is the lowest level 1740 * raw protocol and you must do your own fragmentation at this level. 1741 */ 1742 1743 if (unlikely(sock_flag(sk, SOCK_NOFCS))) { 1744 if (!netif_supports_nofcs(dev)) { 1745 err = -EPROTONOSUPPORT; 1746 goto out_unlock; 1747 } 1748 extra_len = 4; /* We're doing our own CRC */ 1749 } 1750 1751 err = -EMSGSIZE; 1752 if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len) 1753 goto out_unlock; 1754 1755 if (!skb) { 1756 size_t reserved = LL_RESERVED_SPACE(dev); 1757 int tlen = dev->needed_tailroom; 1758 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0; 1759 1760 rcu_read_unlock(); 1761 skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL); 1762 if (skb == NULL) 1763 return -ENOBUFS; 1764 /* FIXME: Save some space for broken drivers that write a hard 1765 * header at transmission time by themselves. PPP is the notable 1766 * one here. This should really be fixed at the driver level. 1767 */ 1768 skb_reserve(skb, reserved); 1769 skb_reset_network_header(skb); 1770 1771 /* Try to align data part correctly */ 1772 if (hhlen) { 1773 skb->data -= hhlen; 1774 skb->tail -= hhlen; 1775 if (len < hhlen) 1776 skb_reset_network_header(skb); 1777 } 1778 err = memcpy_from_msg(skb_put(skb, len), msg, len); 1779 if (err) 1780 goto out_free; 1781 goto retry; 1782 } 1783 1784 if (len > (dev->mtu + dev->hard_header_len + extra_len)) { 1785 /* Earlier code assumed this would be a VLAN pkt, 1786 * double-check this now that we have the actual 1787 * packet in hand. 1788 */ 1789 struct ethhdr *ehdr; 1790 skb_reset_mac_header(skb); 1791 ehdr = eth_hdr(skb); 1792 if (ehdr->h_proto != htons(ETH_P_8021Q)) { 1793 err = -EMSGSIZE; 1794 goto out_unlock; 1795 } 1796 } 1797 1798 skb->protocol = proto; 1799 skb->dev = dev; 1800 skb->priority = sk->sk_priority; 1801 skb->mark = sk->sk_mark; 1802 1803 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags); 1804 1805 if (unlikely(extra_len == 4)) 1806 skb->no_fcs = 1; 1807 1808 skb_probe_transport_header(skb, 0); 1809 1810 dev_queue_xmit(skb); 1811 rcu_read_unlock(); 1812 return len; 1813 1814 out_unlock: 1815 rcu_read_unlock(); 1816 out_free: 1817 kfree_skb(skb); 1818 return err; 1819 } 1820 1821 static unsigned int run_filter(const struct sk_buff *skb, 1822 const struct sock *sk, 1823 unsigned int res) 1824 { 1825 struct sk_filter *filter; 1826 1827 rcu_read_lock(); 1828 filter = rcu_dereference(sk->sk_filter); 1829 if (filter != NULL) 1830 res = SK_RUN_FILTER(filter, skb); 1831 rcu_read_unlock(); 1832 1833 return res; 1834 } 1835 1836 /* 1837 * This function makes lazy skb cloning in hope that most of packets 1838 * are discarded by BPF. 1839 * 1840 * Note tricky part: we DO mangle shared skb! skb->data, skb->len 1841 * and skb->cb are mangled. It works because (and until) packets 1842 * falling here are owned by current CPU. Output packets are cloned 1843 * by dev_queue_xmit_nit(), input packets are processed by net_bh 1844 * sequencially, so that if we return skb to original state on exit, 1845 * we will not harm anyone. 1846 */ 1847 1848 static int packet_rcv(struct sk_buff *skb, struct net_device *dev, 1849 struct packet_type *pt, struct net_device *orig_dev) 1850 { 1851 struct sock *sk; 1852 struct sockaddr_ll *sll; 1853 struct packet_sock *po; 1854 u8 *skb_head = skb->data; 1855 int skb_len = skb->len; 1856 unsigned int snaplen, res; 1857 1858 if (skb->pkt_type == PACKET_LOOPBACK) 1859 goto drop; 1860 1861 sk = pt->af_packet_priv; 1862 po = pkt_sk(sk); 1863 1864 if (!net_eq(dev_net(dev), sock_net(sk))) 1865 goto drop; 1866 1867 skb->dev = dev; 1868 1869 if (dev->header_ops) { 1870 /* The device has an explicit notion of ll header, 1871 * exported to higher levels. 1872 * 1873 * Otherwise, the device hides details of its frame 1874 * structure, so that corresponding packet head is 1875 * never delivered to user. 1876 */ 1877 if (sk->sk_type != SOCK_DGRAM) 1878 skb_push(skb, skb->data - skb_mac_header(skb)); 1879 else if (skb->pkt_type == PACKET_OUTGOING) { 1880 /* Special case: outgoing packets have ll header at head */ 1881 skb_pull(skb, skb_network_offset(skb)); 1882 } 1883 } 1884 1885 snaplen = skb->len; 1886 1887 res = run_filter(skb, sk, snaplen); 1888 if (!res) 1889 goto drop_n_restore; 1890 if (snaplen > res) 1891 snaplen = res; 1892 1893 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) 1894 goto drop_n_acct; 1895 1896 if (skb_shared(skb)) { 1897 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC); 1898 if (nskb == NULL) 1899 goto drop_n_acct; 1900 1901 if (skb_head != skb->data) { 1902 skb->data = skb_head; 1903 skb->len = skb_len; 1904 } 1905 consume_skb(skb); 1906 skb = nskb; 1907 } 1908 1909 sock_skb_cb_check_size(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8); 1910 1911 sll = &PACKET_SKB_CB(skb)->sa.ll; 1912 sll->sll_hatype = dev->type; 1913 sll->sll_pkttype = skb->pkt_type; 1914 if (unlikely(po->origdev)) 1915 sll->sll_ifindex = orig_dev->ifindex; 1916 else 1917 sll->sll_ifindex = dev->ifindex; 1918 1919 sll->sll_halen = dev_parse_header(skb, sll->sll_addr); 1920 1921 /* sll->sll_family and sll->sll_protocol are set in packet_recvmsg(). 1922 * Use their space for storing the original skb length. 1923 */ 1924 PACKET_SKB_CB(skb)->sa.origlen = skb->len; 1925 1926 if (pskb_trim(skb, snaplen)) 1927 goto drop_n_acct; 1928 1929 skb_set_owner_r(skb, sk); 1930 skb->dev = NULL; 1931 skb_dst_drop(skb); 1932 1933 /* drop conntrack reference */ 1934 nf_reset(skb); 1935 1936 spin_lock(&sk->sk_receive_queue.lock); 1937 po->stats.stats1.tp_packets++; 1938 sock_skb_set_dropcount(sk, skb); 1939 __skb_queue_tail(&sk->sk_receive_queue, skb); 1940 spin_unlock(&sk->sk_receive_queue.lock); 1941 sk->sk_data_ready(sk); 1942 return 0; 1943 1944 drop_n_acct: 1945 spin_lock(&sk->sk_receive_queue.lock); 1946 po->stats.stats1.tp_drops++; 1947 atomic_inc(&sk->sk_drops); 1948 spin_unlock(&sk->sk_receive_queue.lock); 1949 1950 drop_n_restore: 1951 if (skb_head != skb->data && skb_shared(skb)) { 1952 skb->data = skb_head; 1953 skb->len = skb_len; 1954 } 1955 drop: 1956 consume_skb(skb); 1957 return 0; 1958 } 1959 1960 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, 1961 struct packet_type *pt, struct net_device *orig_dev) 1962 { 1963 struct sock *sk; 1964 struct packet_sock *po; 1965 struct sockaddr_ll *sll; 1966 union tpacket_uhdr h; 1967 u8 *skb_head = skb->data; 1968 int skb_len = skb->len; 1969 unsigned int snaplen, res; 1970 unsigned long status = TP_STATUS_USER; 1971 unsigned short macoff, netoff, hdrlen; 1972 struct sk_buff *copy_skb = NULL; 1973 struct timespec ts; 1974 __u32 ts_status; 1975 1976 /* struct tpacket{2,3}_hdr is aligned to a multiple of TPACKET_ALIGNMENT. 1977 * We may add members to them until current aligned size without forcing 1978 * userspace to call getsockopt(..., PACKET_HDRLEN, ...). 1979 */ 1980 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h2)) != 32); 1981 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h3)) != 48); 1982 1983 if (skb->pkt_type == PACKET_LOOPBACK) 1984 goto drop; 1985 1986 sk = pt->af_packet_priv; 1987 po = pkt_sk(sk); 1988 1989 if (!net_eq(dev_net(dev), sock_net(sk))) 1990 goto drop; 1991 1992 if (dev->header_ops) { 1993 if (sk->sk_type != SOCK_DGRAM) 1994 skb_push(skb, skb->data - skb_mac_header(skb)); 1995 else if (skb->pkt_type == PACKET_OUTGOING) { 1996 /* Special case: outgoing packets have ll header at head */ 1997 skb_pull(skb, skb_network_offset(skb)); 1998 } 1999 } 2000 2001 snaplen = skb->len; 2002 2003 res = run_filter(skb, sk, snaplen); 2004 if (!res) 2005 goto drop_n_restore; 2006 2007 if (skb->ip_summed == CHECKSUM_PARTIAL) 2008 status |= TP_STATUS_CSUMNOTREADY; 2009 else if (skb->pkt_type != PACKET_OUTGOING && 2010 (skb->ip_summed == CHECKSUM_COMPLETE || 2011 skb_csum_unnecessary(skb))) 2012 status |= TP_STATUS_CSUM_VALID; 2013 2014 if (snaplen > res) 2015 snaplen = res; 2016 2017 if (sk->sk_type == SOCK_DGRAM) { 2018 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 + 2019 po->tp_reserve; 2020 } else { 2021 unsigned int maclen = skb_network_offset(skb); 2022 netoff = TPACKET_ALIGN(po->tp_hdrlen + 2023 (maclen < 16 ? 16 : maclen)) + 2024 po->tp_reserve; 2025 macoff = netoff - maclen; 2026 } 2027 if (po->tp_version <= TPACKET_V2) { 2028 if (macoff + snaplen > po->rx_ring.frame_size) { 2029 if (po->copy_thresh && 2030 atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) { 2031 if (skb_shared(skb)) { 2032 copy_skb = skb_clone(skb, GFP_ATOMIC); 2033 } else { 2034 copy_skb = skb_get(skb); 2035 skb_head = skb->data; 2036 } 2037 if (copy_skb) 2038 skb_set_owner_r(copy_skb, sk); 2039 } 2040 snaplen = po->rx_ring.frame_size - macoff; 2041 if ((int)snaplen < 0) 2042 snaplen = 0; 2043 } 2044 } else if (unlikely(macoff + snaplen > 2045 GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len)) { 2046 u32 nval; 2047 2048 nval = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len - macoff; 2049 pr_err_once("tpacket_rcv: packet too big, clamped from %u to %u. macoff=%u\n", 2050 snaplen, nval, macoff); 2051 snaplen = nval; 2052 if (unlikely((int)snaplen < 0)) { 2053 snaplen = 0; 2054 macoff = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len; 2055 } 2056 } 2057 spin_lock(&sk->sk_receive_queue.lock); 2058 h.raw = packet_current_rx_frame(po, skb, 2059 TP_STATUS_KERNEL, (macoff+snaplen)); 2060 if (!h.raw) 2061 goto ring_is_full; 2062 if (po->tp_version <= TPACKET_V2) { 2063 packet_increment_rx_head(po, &po->rx_ring); 2064 /* 2065 * LOSING will be reported till you read the stats, 2066 * because it's COR - Clear On Read. 2067 * Anyways, moving it for V1/V2 only as V3 doesn't need this 2068 * at packet level. 2069 */ 2070 if (po->stats.stats1.tp_drops) 2071 status |= TP_STATUS_LOSING; 2072 } 2073 po->stats.stats1.tp_packets++; 2074 if (copy_skb) { 2075 status |= TP_STATUS_COPY; 2076 __skb_queue_tail(&sk->sk_receive_queue, copy_skb); 2077 } 2078 spin_unlock(&sk->sk_receive_queue.lock); 2079 2080 skb_copy_bits(skb, 0, h.raw + macoff, snaplen); 2081 2082 if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp))) 2083 getnstimeofday(&ts); 2084 2085 status |= ts_status; 2086 2087 switch (po->tp_version) { 2088 case TPACKET_V1: 2089 h.h1->tp_len = skb->len; 2090 h.h1->tp_snaplen = snaplen; 2091 h.h1->tp_mac = macoff; 2092 h.h1->tp_net = netoff; 2093 h.h1->tp_sec = ts.tv_sec; 2094 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC; 2095 hdrlen = sizeof(*h.h1); 2096 break; 2097 case TPACKET_V2: 2098 h.h2->tp_len = skb->len; 2099 h.h2->tp_snaplen = snaplen; 2100 h.h2->tp_mac = macoff; 2101 h.h2->tp_net = netoff; 2102 h.h2->tp_sec = ts.tv_sec; 2103 h.h2->tp_nsec = ts.tv_nsec; 2104 if (skb_vlan_tag_present(skb)) { 2105 h.h2->tp_vlan_tci = skb_vlan_tag_get(skb); 2106 h.h2->tp_vlan_tpid = ntohs(skb->vlan_proto); 2107 status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID; 2108 } else { 2109 h.h2->tp_vlan_tci = 0; 2110 h.h2->tp_vlan_tpid = 0; 2111 } 2112 memset(h.h2->tp_padding, 0, sizeof(h.h2->tp_padding)); 2113 hdrlen = sizeof(*h.h2); 2114 break; 2115 case TPACKET_V3: 2116 /* tp_nxt_offset,vlan are already populated above. 2117 * So DONT clear those fields here 2118 */ 2119 h.h3->tp_status |= status; 2120 h.h3->tp_len = skb->len; 2121 h.h3->tp_snaplen = snaplen; 2122 h.h3->tp_mac = macoff; 2123 h.h3->tp_net = netoff; 2124 h.h3->tp_sec = ts.tv_sec; 2125 h.h3->tp_nsec = ts.tv_nsec; 2126 memset(h.h3->tp_padding, 0, sizeof(h.h3->tp_padding)); 2127 hdrlen = sizeof(*h.h3); 2128 break; 2129 default: 2130 BUG(); 2131 } 2132 2133 sll = h.raw + TPACKET_ALIGN(hdrlen); 2134 sll->sll_halen = dev_parse_header(skb, sll->sll_addr); 2135 sll->sll_family = AF_PACKET; 2136 sll->sll_hatype = dev->type; 2137 sll->sll_protocol = skb->protocol; 2138 sll->sll_pkttype = skb->pkt_type; 2139 if (unlikely(po->origdev)) 2140 sll->sll_ifindex = orig_dev->ifindex; 2141 else 2142 sll->sll_ifindex = dev->ifindex; 2143 2144 smp_mb(); 2145 2146 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1 2147 if (po->tp_version <= TPACKET_V2) { 2148 u8 *start, *end; 2149 2150 end = (u8 *) PAGE_ALIGN((unsigned long) h.raw + 2151 macoff + snaplen); 2152 2153 for (start = h.raw; start < end; start += PAGE_SIZE) 2154 flush_dcache_page(pgv_to_page(start)); 2155 } 2156 smp_wmb(); 2157 #endif 2158 2159 if (po->tp_version <= TPACKET_V2) { 2160 __packet_set_status(po, h.raw, status); 2161 sk->sk_data_ready(sk); 2162 } else { 2163 prb_clear_blk_fill_status(&po->rx_ring); 2164 } 2165 2166 drop_n_restore: 2167 if (skb_head != skb->data && skb_shared(skb)) { 2168 skb->data = skb_head; 2169 skb->len = skb_len; 2170 } 2171 drop: 2172 kfree_skb(skb); 2173 return 0; 2174 2175 ring_is_full: 2176 po->stats.stats1.tp_drops++; 2177 spin_unlock(&sk->sk_receive_queue.lock); 2178 2179 sk->sk_data_ready(sk); 2180 kfree_skb(copy_skb); 2181 goto drop_n_restore; 2182 } 2183 2184 static void tpacket_destruct_skb(struct sk_buff *skb) 2185 { 2186 struct packet_sock *po = pkt_sk(skb->sk); 2187 2188 if (likely(po->tx_ring.pg_vec)) { 2189 void *ph; 2190 __u32 ts; 2191 2192 ph = skb_shinfo(skb)->destructor_arg; 2193 packet_dec_pending(&po->tx_ring); 2194 2195 ts = __packet_set_timestamp(po, ph, skb); 2196 __packet_set_status(po, ph, TP_STATUS_AVAILABLE | ts); 2197 } 2198 2199 sock_wfree(skb); 2200 } 2201 2202 static bool ll_header_truncated(const struct net_device *dev, int len) 2203 { 2204 /* net device doesn't like empty head */ 2205 if (unlikely(len <= dev->hard_header_len)) { 2206 net_warn_ratelimited("%s: packet size is too short (%d <= %d)\n", 2207 current->comm, len, dev->hard_header_len); 2208 return true; 2209 } 2210 2211 return false; 2212 } 2213 2214 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb, 2215 void *frame, struct net_device *dev, int size_max, 2216 __be16 proto, unsigned char *addr, int hlen) 2217 { 2218 union tpacket_uhdr ph; 2219 int to_write, offset, len, tp_len, nr_frags, len_max; 2220 struct socket *sock = po->sk.sk_socket; 2221 struct page *page; 2222 void *data; 2223 int err; 2224 2225 ph.raw = frame; 2226 2227 skb->protocol = proto; 2228 skb->dev = dev; 2229 skb->priority = po->sk.sk_priority; 2230 skb->mark = po->sk.sk_mark; 2231 sock_tx_timestamp(&po->sk, &skb_shinfo(skb)->tx_flags); 2232 skb_shinfo(skb)->destructor_arg = ph.raw; 2233 2234 switch (po->tp_version) { 2235 case TPACKET_V2: 2236 tp_len = ph.h2->tp_len; 2237 break; 2238 default: 2239 tp_len = ph.h1->tp_len; 2240 break; 2241 } 2242 if (unlikely(tp_len > size_max)) { 2243 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max); 2244 return -EMSGSIZE; 2245 } 2246 2247 skb_reserve(skb, hlen); 2248 skb_reset_network_header(skb); 2249 2250 if (!packet_use_direct_xmit(po)) 2251 skb_probe_transport_header(skb, 0); 2252 if (unlikely(po->tp_tx_has_off)) { 2253 int off_min, off_max, off; 2254 off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll); 2255 off_max = po->tx_ring.frame_size - tp_len; 2256 if (sock->type == SOCK_DGRAM) { 2257 switch (po->tp_version) { 2258 case TPACKET_V2: 2259 off = ph.h2->tp_net; 2260 break; 2261 default: 2262 off = ph.h1->tp_net; 2263 break; 2264 } 2265 } else { 2266 switch (po->tp_version) { 2267 case TPACKET_V2: 2268 off = ph.h2->tp_mac; 2269 break; 2270 default: 2271 off = ph.h1->tp_mac; 2272 break; 2273 } 2274 } 2275 if (unlikely((off < off_min) || (off_max < off))) 2276 return -EINVAL; 2277 data = ph.raw + off; 2278 } else { 2279 data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll); 2280 } 2281 to_write = tp_len; 2282 2283 if (sock->type == SOCK_DGRAM) { 2284 err = dev_hard_header(skb, dev, ntohs(proto), addr, 2285 NULL, tp_len); 2286 if (unlikely(err < 0)) 2287 return -EINVAL; 2288 } else if (dev->hard_header_len) { 2289 if (ll_header_truncated(dev, tp_len)) 2290 return -EINVAL; 2291 2292 skb_push(skb, dev->hard_header_len); 2293 err = skb_store_bits(skb, 0, data, 2294 dev->hard_header_len); 2295 if (unlikely(err)) 2296 return err; 2297 2298 data += dev->hard_header_len; 2299 to_write -= dev->hard_header_len; 2300 } 2301 2302 offset = offset_in_page(data); 2303 len_max = PAGE_SIZE - offset; 2304 len = ((to_write > len_max) ? len_max : to_write); 2305 2306 skb->data_len = to_write; 2307 skb->len += to_write; 2308 skb->truesize += to_write; 2309 atomic_add(to_write, &po->sk.sk_wmem_alloc); 2310 2311 while (likely(to_write)) { 2312 nr_frags = skb_shinfo(skb)->nr_frags; 2313 2314 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) { 2315 pr_err("Packet exceed the number of skb frags(%lu)\n", 2316 MAX_SKB_FRAGS); 2317 return -EFAULT; 2318 } 2319 2320 page = pgv_to_page(data); 2321 data += len; 2322 flush_dcache_page(page); 2323 get_page(page); 2324 skb_fill_page_desc(skb, nr_frags, page, offset, len); 2325 to_write -= len; 2326 offset = 0; 2327 len_max = PAGE_SIZE; 2328 len = ((to_write > len_max) ? len_max : to_write); 2329 } 2330 2331 return tp_len; 2332 } 2333 2334 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg) 2335 { 2336 struct sk_buff *skb; 2337 struct net_device *dev; 2338 __be16 proto; 2339 int err, reserve = 0; 2340 void *ph; 2341 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name); 2342 bool need_wait = !(msg->msg_flags & MSG_DONTWAIT); 2343 int tp_len, size_max; 2344 unsigned char *addr; 2345 int len_sum = 0; 2346 int status = TP_STATUS_AVAILABLE; 2347 int hlen, tlen; 2348 2349 mutex_lock(&po->pg_vec_lock); 2350 2351 if (likely(saddr == NULL)) { 2352 dev = packet_cached_dev_get(po); 2353 proto = po->num; 2354 addr = NULL; 2355 } else { 2356 err = -EINVAL; 2357 if (msg->msg_namelen < sizeof(struct sockaddr_ll)) 2358 goto out; 2359 if (msg->msg_namelen < (saddr->sll_halen 2360 + offsetof(struct sockaddr_ll, 2361 sll_addr))) 2362 goto out; 2363 proto = saddr->sll_protocol; 2364 addr = saddr->sll_addr; 2365 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex); 2366 } 2367 2368 err = -ENXIO; 2369 if (unlikely(dev == NULL)) 2370 goto out; 2371 err = -ENETDOWN; 2372 if (unlikely(!(dev->flags & IFF_UP))) 2373 goto out_put; 2374 2375 reserve = dev->hard_header_len + VLAN_HLEN; 2376 size_max = po->tx_ring.frame_size 2377 - (po->tp_hdrlen - sizeof(struct sockaddr_ll)); 2378 2379 if (size_max > dev->mtu + reserve) 2380 size_max = dev->mtu + reserve; 2381 2382 do { 2383 ph = packet_current_frame(po, &po->tx_ring, 2384 TP_STATUS_SEND_REQUEST); 2385 if (unlikely(ph == NULL)) { 2386 if (need_wait && need_resched()) 2387 schedule(); 2388 continue; 2389 } 2390 2391 status = TP_STATUS_SEND_REQUEST; 2392 hlen = LL_RESERVED_SPACE(dev); 2393 tlen = dev->needed_tailroom; 2394 skb = sock_alloc_send_skb(&po->sk, 2395 hlen + tlen + sizeof(struct sockaddr_ll), 2396 !need_wait, &err); 2397 2398 if (unlikely(skb == NULL)) { 2399 /* we assume the socket was initially writeable ... */ 2400 if (likely(len_sum > 0)) 2401 err = len_sum; 2402 goto out_status; 2403 } 2404 tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto, 2405 addr, hlen); 2406 if (tp_len > dev->mtu + dev->hard_header_len) { 2407 struct ethhdr *ehdr; 2408 /* Earlier code assumed this would be a VLAN pkt, 2409 * double-check this now that we have the actual 2410 * packet in hand. 2411 */ 2412 2413 skb_reset_mac_header(skb); 2414 ehdr = eth_hdr(skb); 2415 if (ehdr->h_proto != htons(ETH_P_8021Q)) 2416 tp_len = -EMSGSIZE; 2417 } 2418 if (unlikely(tp_len < 0)) { 2419 if (po->tp_loss) { 2420 __packet_set_status(po, ph, 2421 TP_STATUS_AVAILABLE); 2422 packet_increment_head(&po->tx_ring); 2423 kfree_skb(skb); 2424 continue; 2425 } else { 2426 status = TP_STATUS_WRONG_FORMAT; 2427 err = tp_len; 2428 goto out_status; 2429 } 2430 } 2431 2432 packet_pick_tx_queue(dev, skb); 2433 2434 skb->destructor = tpacket_destruct_skb; 2435 __packet_set_status(po, ph, TP_STATUS_SENDING); 2436 packet_inc_pending(&po->tx_ring); 2437 2438 status = TP_STATUS_SEND_REQUEST; 2439 err = po->xmit(skb); 2440 if (unlikely(err > 0)) { 2441 err = net_xmit_errno(err); 2442 if (err && __packet_get_status(po, ph) == 2443 TP_STATUS_AVAILABLE) { 2444 /* skb was destructed already */ 2445 skb = NULL; 2446 goto out_status; 2447 } 2448 /* 2449 * skb was dropped but not destructed yet; 2450 * let's treat it like congestion or err < 0 2451 */ 2452 err = 0; 2453 } 2454 packet_increment_head(&po->tx_ring); 2455 len_sum += tp_len; 2456 } while (likely((ph != NULL) || 2457 /* Note: packet_read_pending() might be slow if we have 2458 * to call it as it's per_cpu variable, but in fast-path 2459 * we already short-circuit the loop with the first 2460 * condition, and luckily don't have to go that path 2461 * anyway. 2462 */ 2463 (need_wait && packet_read_pending(&po->tx_ring)))); 2464 2465 err = len_sum; 2466 goto out_put; 2467 2468 out_status: 2469 __packet_set_status(po, ph, status); 2470 kfree_skb(skb); 2471 out_put: 2472 dev_put(dev); 2473 out: 2474 mutex_unlock(&po->pg_vec_lock); 2475 return err; 2476 } 2477 2478 static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad, 2479 size_t reserve, size_t len, 2480 size_t linear, int noblock, 2481 int *err) 2482 { 2483 struct sk_buff *skb; 2484 2485 /* Under a page? Don't bother with paged skb. */ 2486 if (prepad + len < PAGE_SIZE || !linear) 2487 linear = len; 2488 2489 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock, 2490 err, 0); 2491 if (!skb) 2492 return NULL; 2493 2494 skb_reserve(skb, reserve); 2495 skb_put(skb, linear); 2496 skb->data_len = len - linear; 2497 skb->len += len - linear; 2498 2499 return skb; 2500 } 2501 2502 static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len) 2503 { 2504 struct sock *sk = sock->sk; 2505 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name); 2506 struct sk_buff *skb; 2507 struct net_device *dev; 2508 __be16 proto; 2509 unsigned char *addr; 2510 int err, reserve = 0; 2511 struct virtio_net_hdr vnet_hdr = { 0 }; 2512 int offset = 0; 2513 int vnet_hdr_len; 2514 struct packet_sock *po = pkt_sk(sk); 2515 unsigned short gso_type = 0; 2516 int hlen, tlen; 2517 int extra_len = 0; 2518 ssize_t n; 2519 2520 /* 2521 * Get and verify the address. 2522 */ 2523 2524 if (likely(saddr == NULL)) { 2525 dev = packet_cached_dev_get(po); 2526 proto = po->num; 2527 addr = NULL; 2528 } else { 2529 err = -EINVAL; 2530 if (msg->msg_namelen < sizeof(struct sockaddr_ll)) 2531 goto out; 2532 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr))) 2533 goto out; 2534 proto = saddr->sll_protocol; 2535 addr = saddr->sll_addr; 2536 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex); 2537 } 2538 2539 err = -ENXIO; 2540 if (unlikely(dev == NULL)) 2541 goto out_unlock; 2542 err = -ENETDOWN; 2543 if (unlikely(!(dev->flags & IFF_UP))) 2544 goto out_unlock; 2545 2546 if (sock->type == SOCK_RAW) 2547 reserve = dev->hard_header_len; 2548 if (po->has_vnet_hdr) { 2549 vnet_hdr_len = sizeof(vnet_hdr); 2550 2551 err = -EINVAL; 2552 if (len < vnet_hdr_len) 2553 goto out_unlock; 2554 2555 len -= vnet_hdr_len; 2556 2557 err = -EFAULT; 2558 n = copy_from_iter(&vnet_hdr, vnet_hdr_len, &msg->msg_iter); 2559 if (n != vnet_hdr_len) 2560 goto out_unlock; 2561 2562 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && 2563 (__virtio16_to_cpu(false, vnet_hdr.csum_start) + 2564 __virtio16_to_cpu(false, vnet_hdr.csum_offset) + 2 > 2565 __virtio16_to_cpu(false, vnet_hdr.hdr_len))) 2566 vnet_hdr.hdr_len = __cpu_to_virtio16(false, 2567 __virtio16_to_cpu(false, vnet_hdr.csum_start) + 2568 __virtio16_to_cpu(false, vnet_hdr.csum_offset) + 2); 2569 2570 err = -EINVAL; 2571 if (__virtio16_to_cpu(false, vnet_hdr.hdr_len) > len) 2572 goto out_unlock; 2573 2574 if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) { 2575 switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { 2576 case VIRTIO_NET_HDR_GSO_TCPV4: 2577 gso_type = SKB_GSO_TCPV4; 2578 break; 2579 case VIRTIO_NET_HDR_GSO_TCPV6: 2580 gso_type = SKB_GSO_TCPV6; 2581 break; 2582 case VIRTIO_NET_HDR_GSO_UDP: 2583 gso_type = SKB_GSO_UDP; 2584 break; 2585 default: 2586 goto out_unlock; 2587 } 2588 2589 if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN) 2590 gso_type |= SKB_GSO_TCP_ECN; 2591 2592 if (vnet_hdr.gso_size == 0) 2593 goto out_unlock; 2594 2595 } 2596 } 2597 2598 if (unlikely(sock_flag(sk, SOCK_NOFCS))) { 2599 if (!netif_supports_nofcs(dev)) { 2600 err = -EPROTONOSUPPORT; 2601 goto out_unlock; 2602 } 2603 extra_len = 4; /* We're doing our own CRC */ 2604 } 2605 2606 err = -EMSGSIZE; 2607 if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN + extra_len)) 2608 goto out_unlock; 2609 2610 err = -ENOBUFS; 2611 hlen = LL_RESERVED_SPACE(dev); 2612 tlen = dev->needed_tailroom; 2613 skb = packet_alloc_skb(sk, hlen + tlen, hlen, len, 2614 __virtio16_to_cpu(false, vnet_hdr.hdr_len), 2615 msg->msg_flags & MSG_DONTWAIT, &err); 2616 if (skb == NULL) 2617 goto out_unlock; 2618 2619 skb_set_network_header(skb, reserve); 2620 2621 err = -EINVAL; 2622 if (sock->type == SOCK_DGRAM) { 2623 offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len); 2624 if (unlikely(offset < 0)) 2625 goto out_free; 2626 } else { 2627 if (ll_header_truncated(dev, len)) 2628 goto out_free; 2629 } 2630 2631 /* Returns -EFAULT on error */ 2632 err = skb_copy_datagram_from_iter(skb, offset, &msg->msg_iter, len); 2633 if (err) 2634 goto out_free; 2635 2636 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags); 2637 2638 if (!gso_type && (len > dev->mtu + reserve + extra_len)) { 2639 /* Earlier code assumed this would be a VLAN pkt, 2640 * double-check this now that we have the actual 2641 * packet in hand. 2642 */ 2643 struct ethhdr *ehdr; 2644 skb_reset_mac_header(skb); 2645 ehdr = eth_hdr(skb); 2646 if (ehdr->h_proto != htons(ETH_P_8021Q)) { 2647 err = -EMSGSIZE; 2648 goto out_free; 2649 } 2650 } 2651 2652 skb->protocol = proto; 2653 skb->dev = dev; 2654 skb->priority = sk->sk_priority; 2655 skb->mark = sk->sk_mark; 2656 2657 packet_pick_tx_queue(dev, skb); 2658 2659 if (po->has_vnet_hdr) { 2660 if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) { 2661 u16 s = __virtio16_to_cpu(false, vnet_hdr.csum_start); 2662 u16 o = __virtio16_to_cpu(false, vnet_hdr.csum_offset); 2663 if (!skb_partial_csum_set(skb, s, o)) { 2664 err = -EINVAL; 2665 goto out_free; 2666 } 2667 } 2668 2669 skb_shinfo(skb)->gso_size = 2670 __virtio16_to_cpu(false, vnet_hdr.gso_size); 2671 skb_shinfo(skb)->gso_type = gso_type; 2672 2673 /* Header must be checked, and gso_segs computed. */ 2674 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY; 2675 skb_shinfo(skb)->gso_segs = 0; 2676 2677 len += vnet_hdr_len; 2678 } 2679 2680 if (!packet_use_direct_xmit(po)) 2681 skb_probe_transport_header(skb, reserve); 2682 if (unlikely(extra_len == 4)) 2683 skb->no_fcs = 1; 2684 2685 err = po->xmit(skb); 2686 if (err > 0 && (err = net_xmit_errno(err)) != 0) 2687 goto out_unlock; 2688 2689 dev_put(dev); 2690 2691 return len; 2692 2693 out_free: 2694 kfree_skb(skb); 2695 out_unlock: 2696 if (dev) 2697 dev_put(dev); 2698 out: 2699 return err; 2700 } 2701 2702 static int packet_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) 2703 { 2704 struct sock *sk = sock->sk; 2705 struct packet_sock *po = pkt_sk(sk); 2706 2707 if (po->tx_ring.pg_vec) 2708 return tpacket_snd(po, msg); 2709 else 2710 return packet_snd(sock, msg, len); 2711 } 2712 2713 /* 2714 * Close a PACKET socket. This is fairly simple. We immediately go 2715 * to 'closed' state and remove our protocol entry in the device list. 2716 */ 2717 2718 static int packet_release(struct socket *sock) 2719 { 2720 struct sock *sk = sock->sk; 2721 struct packet_sock *po; 2722 struct net *net; 2723 union tpacket_req_u req_u; 2724 2725 if (!sk) 2726 return 0; 2727 2728 net = sock_net(sk); 2729 po = pkt_sk(sk); 2730 2731 mutex_lock(&net->packet.sklist_lock); 2732 sk_del_node_init_rcu(sk); 2733 mutex_unlock(&net->packet.sklist_lock); 2734 2735 preempt_disable(); 2736 sock_prot_inuse_add(net, sk->sk_prot, -1); 2737 preempt_enable(); 2738 2739 spin_lock(&po->bind_lock); 2740 unregister_prot_hook(sk, false); 2741 packet_cached_dev_reset(po); 2742 2743 if (po->prot_hook.dev) { 2744 dev_put(po->prot_hook.dev); 2745 po->prot_hook.dev = NULL; 2746 } 2747 spin_unlock(&po->bind_lock); 2748 2749 packet_flush_mclist(sk); 2750 2751 if (po->rx_ring.pg_vec) { 2752 memset(&req_u, 0, sizeof(req_u)); 2753 packet_set_ring(sk, &req_u, 1, 0); 2754 } 2755 2756 if (po->tx_ring.pg_vec) { 2757 memset(&req_u, 0, sizeof(req_u)); 2758 packet_set_ring(sk, &req_u, 1, 1); 2759 } 2760 2761 fanout_release(sk); 2762 2763 synchronize_net(); 2764 /* 2765 * Now the socket is dead. No more input will appear. 2766 */ 2767 sock_orphan(sk); 2768 sock->sk = NULL; 2769 2770 /* Purge queues */ 2771 2772 skb_queue_purge(&sk->sk_receive_queue); 2773 packet_free_pending(po); 2774 sk_refcnt_debug_release(sk); 2775 2776 sock_put(sk); 2777 return 0; 2778 } 2779 2780 /* 2781 * Attach a packet hook. 2782 */ 2783 2784 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 proto) 2785 { 2786 struct packet_sock *po = pkt_sk(sk); 2787 const struct net_device *dev_curr; 2788 __be16 proto_curr; 2789 bool need_rehook; 2790 2791 if (po->fanout) { 2792 if (dev) 2793 dev_put(dev); 2794 2795 return -EINVAL; 2796 } 2797 2798 lock_sock(sk); 2799 spin_lock(&po->bind_lock); 2800 2801 proto_curr = po->prot_hook.type; 2802 dev_curr = po->prot_hook.dev; 2803 2804 need_rehook = proto_curr != proto || dev_curr != dev; 2805 2806 if (need_rehook) { 2807 unregister_prot_hook(sk, true); 2808 2809 po->num = proto; 2810 po->prot_hook.type = proto; 2811 2812 if (po->prot_hook.dev) 2813 dev_put(po->prot_hook.dev); 2814 2815 po->prot_hook.dev = dev; 2816 2817 po->ifindex = dev ? dev->ifindex : 0; 2818 packet_cached_dev_assign(po, dev); 2819 } 2820 2821 if (proto == 0 || !need_rehook) 2822 goto out_unlock; 2823 2824 if (!dev || (dev->flags & IFF_UP)) { 2825 register_prot_hook(sk); 2826 } else { 2827 sk->sk_err = ENETDOWN; 2828 if (!sock_flag(sk, SOCK_DEAD)) 2829 sk->sk_error_report(sk); 2830 } 2831 2832 out_unlock: 2833 spin_unlock(&po->bind_lock); 2834 release_sock(sk); 2835 return 0; 2836 } 2837 2838 /* 2839 * Bind a packet socket to a device 2840 */ 2841 2842 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr, 2843 int addr_len) 2844 { 2845 struct sock *sk = sock->sk; 2846 char name[15]; 2847 struct net_device *dev; 2848 int err = -ENODEV; 2849 2850 /* 2851 * Check legality 2852 */ 2853 2854 if (addr_len != sizeof(struct sockaddr)) 2855 return -EINVAL; 2856 strlcpy(name, uaddr->sa_data, sizeof(name)); 2857 2858 dev = dev_get_by_name(sock_net(sk), name); 2859 if (dev) 2860 err = packet_do_bind(sk, dev, pkt_sk(sk)->num); 2861 return err; 2862 } 2863 2864 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) 2865 { 2866 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr; 2867 struct sock *sk = sock->sk; 2868 struct net_device *dev = NULL; 2869 int err; 2870 2871 2872 /* 2873 * Check legality 2874 */ 2875 2876 if (addr_len < sizeof(struct sockaddr_ll)) 2877 return -EINVAL; 2878 if (sll->sll_family != AF_PACKET) 2879 return -EINVAL; 2880 2881 if (sll->sll_ifindex) { 2882 err = -ENODEV; 2883 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex); 2884 if (dev == NULL) 2885 goto out; 2886 } 2887 err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num); 2888 2889 out: 2890 return err; 2891 } 2892 2893 static struct proto packet_proto = { 2894 .name = "PACKET", 2895 .owner = THIS_MODULE, 2896 .obj_size = sizeof(struct packet_sock), 2897 }; 2898 2899 /* 2900 * Create a packet of type SOCK_PACKET. 2901 */ 2902 2903 static int packet_create(struct net *net, struct socket *sock, int protocol, 2904 int kern) 2905 { 2906 struct sock *sk; 2907 struct packet_sock *po; 2908 __be16 proto = (__force __be16)protocol; /* weird, but documented */ 2909 int err; 2910 2911 if (!ns_capable(net->user_ns, CAP_NET_RAW)) 2912 return -EPERM; 2913 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW && 2914 sock->type != SOCK_PACKET) 2915 return -ESOCKTNOSUPPORT; 2916 2917 sock->state = SS_UNCONNECTED; 2918 2919 err = -ENOBUFS; 2920 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto, kern); 2921 if (sk == NULL) 2922 goto out; 2923 2924 sock->ops = &packet_ops; 2925 if (sock->type == SOCK_PACKET) 2926 sock->ops = &packet_ops_spkt; 2927 2928 sock_init_data(sock, sk); 2929 2930 po = pkt_sk(sk); 2931 sk->sk_family = PF_PACKET; 2932 po->num = proto; 2933 po->xmit = dev_queue_xmit; 2934 2935 err = packet_alloc_pending(po); 2936 if (err) 2937 goto out2; 2938 2939 packet_cached_dev_reset(po); 2940 2941 sk->sk_destruct = packet_sock_destruct; 2942 sk_refcnt_debug_inc(sk); 2943 2944 /* 2945 * Attach a protocol block 2946 */ 2947 2948 spin_lock_init(&po->bind_lock); 2949 mutex_init(&po->pg_vec_lock); 2950 po->rollover = NULL; 2951 po->prot_hook.func = packet_rcv; 2952 2953 if (sock->type == SOCK_PACKET) 2954 po->prot_hook.func = packet_rcv_spkt; 2955 2956 po->prot_hook.af_packet_priv = sk; 2957 2958 if (proto) { 2959 po->prot_hook.type = proto; 2960 register_prot_hook(sk); 2961 } 2962 2963 mutex_lock(&net->packet.sklist_lock); 2964 sk_add_node_rcu(sk, &net->packet.sklist); 2965 mutex_unlock(&net->packet.sklist_lock); 2966 2967 preempt_disable(); 2968 sock_prot_inuse_add(net, &packet_proto, 1); 2969 preempt_enable(); 2970 2971 return 0; 2972 out2: 2973 sk_free(sk); 2974 out: 2975 return err; 2976 } 2977 2978 /* 2979 * Pull a packet from our receive queue and hand it to the user. 2980 * If necessary we block. 2981 */ 2982 2983 static int packet_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, 2984 int flags) 2985 { 2986 struct sock *sk = sock->sk; 2987 struct sk_buff *skb; 2988 int copied, err; 2989 int vnet_hdr_len = 0; 2990 unsigned int origlen = 0; 2991 2992 err = -EINVAL; 2993 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE)) 2994 goto out; 2995 2996 #if 0 2997 /* What error should we return now? EUNATTACH? */ 2998 if (pkt_sk(sk)->ifindex < 0) 2999 return -ENODEV; 3000 #endif 3001 3002 if (flags & MSG_ERRQUEUE) { 3003 err = sock_recv_errqueue(sk, msg, len, 3004 SOL_PACKET, PACKET_TX_TIMESTAMP); 3005 goto out; 3006 } 3007 3008 /* 3009 * Call the generic datagram receiver. This handles all sorts 3010 * of horrible races and re-entrancy so we can forget about it 3011 * in the protocol layers. 3012 * 3013 * Now it will return ENETDOWN, if device have just gone down, 3014 * but then it will block. 3015 */ 3016 3017 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err); 3018 3019 /* 3020 * An error occurred so return it. Because skb_recv_datagram() 3021 * handles the blocking we don't see and worry about blocking 3022 * retries. 3023 */ 3024 3025 if (skb == NULL) 3026 goto out; 3027 3028 if (pkt_sk(sk)->pressure) 3029 packet_rcv_has_room(pkt_sk(sk), NULL); 3030 3031 if (pkt_sk(sk)->has_vnet_hdr) { 3032 struct virtio_net_hdr vnet_hdr = { 0 }; 3033 3034 err = -EINVAL; 3035 vnet_hdr_len = sizeof(vnet_hdr); 3036 if (len < vnet_hdr_len) 3037 goto out_free; 3038 3039 len -= vnet_hdr_len; 3040 3041 if (skb_is_gso(skb)) { 3042 struct skb_shared_info *sinfo = skb_shinfo(skb); 3043 3044 /* This is a hint as to how much should be linear. */ 3045 vnet_hdr.hdr_len = 3046 __cpu_to_virtio16(false, skb_headlen(skb)); 3047 vnet_hdr.gso_size = 3048 __cpu_to_virtio16(false, sinfo->gso_size); 3049 if (sinfo->gso_type & SKB_GSO_TCPV4) 3050 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4; 3051 else if (sinfo->gso_type & SKB_GSO_TCPV6) 3052 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6; 3053 else if (sinfo->gso_type & SKB_GSO_UDP) 3054 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP; 3055 else if (sinfo->gso_type & SKB_GSO_FCOE) 3056 goto out_free; 3057 else 3058 BUG(); 3059 if (sinfo->gso_type & SKB_GSO_TCP_ECN) 3060 vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN; 3061 } else 3062 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE; 3063 3064 if (skb->ip_summed == CHECKSUM_PARTIAL) { 3065 vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; 3066 vnet_hdr.csum_start = __cpu_to_virtio16(false, 3067 skb_checksum_start_offset(skb)); 3068 vnet_hdr.csum_offset = __cpu_to_virtio16(false, 3069 skb->csum_offset); 3070 } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) { 3071 vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID; 3072 } /* else everything is zero */ 3073 3074 err = memcpy_to_msg(msg, (void *)&vnet_hdr, vnet_hdr_len); 3075 if (err < 0) 3076 goto out_free; 3077 } 3078 3079 /* You lose any data beyond the buffer you gave. If it worries 3080 * a user program they can ask the device for its MTU 3081 * anyway. 3082 */ 3083 copied = skb->len; 3084 if (copied > len) { 3085 copied = len; 3086 msg->msg_flags |= MSG_TRUNC; 3087 } 3088 3089 err = skb_copy_datagram_msg(skb, 0, msg, copied); 3090 if (err) 3091 goto out_free; 3092 3093 if (sock->type != SOCK_PACKET) { 3094 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll; 3095 3096 /* Original length was stored in sockaddr_ll fields */ 3097 origlen = PACKET_SKB_CB(skb)->sa.origlen; 3098 sll->sll_family = AF_PACKET; 3099 sll->sll_protocol = skb->protocol; 3100 } 3101 3102 sock_recv_ts_and_drops(msg, sk, skb); 3103 3104 if (msg->msg_name) { 3105 /* If the address length field is there to be filled 3106 * in, we fill it in now. 3107 */ 3108 if (sock->type == SOCK_PACKET) { 3109 __sockaddr_check_size(sizeof(struct sockaddr_pkt)); 3110 msg->msg_namelen = sizeof(struct sockaddr_pkt); 3111 } else { 3112 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll; 3113 3114 msg->msg_namelen = sll->sll_halen + 3115 offsetof(struct sockaddr_ll, sll_addr); 3116 } 3117 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa, 3118 msg->msg_namelen); 3119 } 3120 3121 if (pkt_sk(sk)->auxdata) { 3122 struct tpacket_auxdata aux; 3123 3124 aux.tp_status = TP_STATUS_USER; 3125 if (skb->ip_summed == CHECKSUM_PARTIAL) 3126 aux.tp_status |= TP_STATUS_CSUMNOTREADY; 3127 else if (skb->pkt_type != PACKET_OUTGOING && 3128 (skb->ip_summed == CHECKSUM_COMPLETE || 3129 skb_csum_unnecessary(skb))) 3130 aux.tp_status |= TP_STATUS_CSUM_VALID; 3131 3132 aux.tp_len = origlen; 3133 aux.tp_snaplen = skb->len; 3134 aux.tp_mac = 0; 3135 aux.tp_net = skb_network_offset(skb); 3136 if (skb_vlan_tag_present(skb)) { 3137 aux.tp_vlan_tci = skb_vlan_tag_get(skb); 3138 aux.tp_vlan_tpid = ntohs(skb->vlan_proto); 3139 aux.tp_status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID; 3140 } else { 3141 aux.tp_vlan_tci = 0; 3142 aux.tp_vlan_tpid = 0; 3143 } 3144 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux); 3145 } 3146 3147 /* 3148 * Free or return the buffer as appropriate. Again this 3149 * hides all the races and re-entrancy issues from us. 3150 */ 3151 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied); 3152 3153 out_free: 3154 skb_free_datagram(sk, skb); 3155 out: 3156 return err; 3157 } 3158 3159 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr, 3160 int *uaddr_len, int peer) 3161 { 3162 struct net_device *dev; 3163 struct sock *sk = sock->sk; 3164 3165 if (peer) 3166 return -EOPNOTSUPP; 3167 3168 uaddr->sa_family = AF_PACKET; 3169 memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data)); 3170 rcu_read_lock(); 3171 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex); 3172 if (dev) 3173 strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data)); 3174 rcu_read_unlock(); 3175 *uaddr_len = sizeof(*uaddr); 3176 3177 return 0; 3178 } 3179 3180 static int packet_getname(struct socket *sock, struct sockaddr *uaddr, 3181 int *uaddr_len, int peer) 3182 { 3183 struct net_device *dev; 3184 struct sock *sk = sock->sk; 3185 struct packet_sock *po = pkt_sk(sk); 3186 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr); 3187 3188 if (peer) 3189 return -EOPNOTSUPP; 3190 3191 sll->sll_family = AF_PACKET; 3192 sll->sll_ifindex = po->ifindex; 3193 sll->sll_protocol = po->num; 3194 sll->sll_pkttype = 0; 3195 rcu_read_lock(); 3196 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex); 3197 if (dev) { 3198 sll->sll_hatype = dev->type; 3199 sll->sll_halen = dev->addr_len; 3200 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len); 3201 } else { 3202 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */ 3203 sll->sll_halen = 0; 3204 } 3205 rcu_read_unlock(); 3206 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen; 3207 3208 return 0; 3209 } 3210 3211 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i, 3212 int what) 3213 { 3214 switch (i->type) { 3215 case PACKET_MR_MULTICAST: 3216 if (i->alen != dev->addr_len) 3217 return -EINVAL; 3218 if (what > 0) 3219 return dev_mc_add(dev, i->addr); 3220 else 3221 return dev_mc_del(dev, i->addr); 3222 break; 3223 case PACKET_MR_PROMISC: 3224 return dev_set_promiscuity(dev, what); 3225 case PACKET_MR_ALLMULTI: 3226 return dev_set_allmulti(dev, what); 3227 case PACKET_MR_UNICAST: 3228 if (i->alen != dev->addr_len) 3229 return -EINVAL; 3230 if (what > 0) 3231 return dev_uc_add(dev, i->addr); 3232 else 3233 return dev_uc_del(dev, i->addr); 3234 break; 3235 default: 3236 break; 3237 } 3238 return 0; 3239 } 3240 3241 static void packet_dev_mclist_delete(struct net_device *dev, 3242 struct packet_mclist **mlp) 3243 { 3244 struct packet_mclist *ml; 3245 3246 while ((ml = *mlp) != NULL) { 3247 if (ml->ifindex == dev->ifindex) { 3248 packet_dev_mc(dev, ml, -1); 3249 *mlp = ml->next; 3250 kfree(ml); 3251 } else 3252 mlp = &ml->next; 3253 } 3254 } 3255 3256 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq) 3257 { 3258 struct packet_sock *po = pkt_sk(sk); 3259 struct packet_mclist *ml, *i; 3260 struct net_device *dev; 3261 int err; 3262 3263 rtnl_lock(); 3264 3265 err = -ENODEV; 3266 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex); 3267 if (!dev) 3268 goto done; 3269 3270 err = -EINVAL; 3271 if (mreq->mr_alen > dev->addr_len) 3272 goto done; 3273 3274 err = -ENOBUFS; 3275 i = kmalloc(sizeof(*i), GFP_KERNEL); 3276 if (i == NULL) 3277 goto done; 3278 3279 err = 0; 3280 for (ml = po->mclist; ml; ml = ml->next) { 3281 if (ml->ifindex == mreq->mr_ifindex && 3282 ml->type == mreq->mr_type && 3283 ml->alen == mreq->mr_alen && 3284 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) { 3285 ml->count++; 3286 /* Free the new element ... */ 3287 kfree(i); 3288 goto done; 3289 } 3290 } 3291 3292 i->type = mreq->mr_type; 3293 i->ifindex = mreq->mr_ifindex; 3294 i->alen = mreq->mr_alen; 3295 memcpy(i->addr, mreq->mr_address, i->alen); 3296 i->count = 1; 3297 i->next = po->mclist; 3298 po->mclist = i; 3299 err = packet_dev_mc(dev, i, 1); 3300 if (err) { 3301 po->mclist = i->next; 3302 kfree(i); 3303 } 3304 3305 done: 3306 rtnl_unlock(); 3307 return err; 3308 } 3309 3310 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq) 3311 { 3312 struct packet_mclist *ml, **mlp; 3313 3314 rtnl_lock(); 3315 3316 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) { 3317 if (ml->ifindex == mreq->mr_ifindex && 3318 ml->type == mreq->mr_type && 3319 ml->alen == mreq->mr_alen && 3320 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) { 3321 if (--ml->count == 0) { 3322 struct net_device *dev; 3323 *mlp = ml->next; 3324 dev = __dev_get_by_index(sock_net(sk), ml->ifindex); 3325 if (dev) 3326 packet_dev_mc(dev, ml, -1); 3327 kfree(ml); 3328 } 3329 break; 3330 } 3331 } 3332 rtnl_unlock(); 3333 return 0; 3334 } 3335 3336 static void packet_flush_mclist(struct sock *sk) 3337 { 3338 struct packet_sock *po = pkt_sk(sk); 3339 struct packet_mclist *ml; 3340 3341 if (!po->mclist) 3342 return; 3343 3344 rtnl_lock(); 3345 while ((ml = po->mclist) != NULL) { 3346 struct net_device *dev; 3347 3348 po->mclist = ml->next; 3349 dev = __dev_get_by_index(sock_net(sk), ml->ifindex); 3350 if (dev != NULL) 3351 packet_dev_mc(dev, ml, -1); 3352 kfree(ml); 3353 } 3354 rtnl_unlock(); 3355 } 3356 3357 static int 3358 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen) 3359 { 3360 struct sock *sk = sock->sk; 3361 struct packet_sock *po = pkt_sk(sk); 3362 int ret; 3363 3364 if (level != SOL_PACKET) 3365 return -ENOPROTOOPT; 3366 3367 switch (optname) { 3368 case PACKET_ADD_MEMBERSHIP: 3369 case PACKET_DROP_MEMBERSHIP: 3370 { 3371 struct packet_mreq_max mreq; 3372 int len = optlen; 3373 memset(&mreq, 0, sizeof(mreq)); 3374 if (len < sizeof(struct packet_mreq)) 3375 return -EINVAL; 3376 if (len > sizeof(mreq)) 3377 len = sizeof(mreq); 3378 if (copy_from_user(&mreq, optval, len)) 3379 return -EFAULT; 3380 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address))) 3381 return -EINVAL; 3382 if (optname == PACKET_ADD_MEMBERSHIP) 3383 ret = packet_mc_add(sk, &mreq); 3384 else 3385 ret = packet_mc_drop(sk, &mreq); 3386 return ret; 3387 } 3388 3389 case PACKET_RX_RING: 3390 case PACKET_TX_RING: 3391 { 3392 union tpacket_req_u req_u; 3393 int len; 3394 3395 switch (po->tp_version) { 3396 case TPACKET_V1: 3397 case TPACKET_V2: 3398 len = sizeof(req_u.req); 3399 break; 3400 case TPACKET_V3: 3401 default: 3402 len = sizeof(req_u.req3); 3403 break; 3404 } 3405 if (optlen < len) 3406 return -EINVAL; 3407 if (pkt_sk(sk)->has_vnet_hdr) 3408 return -EINVAL; 3409 if (copy_from_user(&req_u.req, optval, len)) 3410 return -EFAULT; 3411 return packet_set_ring(sk, &req_u, 0, 3412 optname == PACKET_TX_RING); 3413 } 3414 case PACKET_COPY_THRESH: 3415 { 3416 int val; 3417 3418 if (optlen != sizeof(val)) 3419 return -EINVAL; 3420 if (copy_from_user(&val, optval, sizeof(val))) 3421 return -EFAULT; 3422 3423 pkt_sk(sk)->copy_thresh = val; 3424 return 0; 3425 } 3426 case PACKET_VERSION: 3427 { 3428 int val; 3429 3430 if (optlen != sizeof(val)) 3431 return -EINVAL; 3432 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 3433 return -EBUSY; 3434 if (copy_from_user(&val, optval, sizeof(val))) 3435 return -EFAULT; 3436 switch (val) { 3437 case TPACKET_V1: 3438 case TPACKET_V2: 3439 case TPACKET_V3: 3440 po->tp_version = val; 3441 return 0; 3442 default: 3443 return -EINVAL; 3444 } 3445 } 3446 case PACKET_RESERVE: 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_reserve = val; 3457 return 0; 3458 } 3459 case PACKET_LOSS: 3460 { 3461 unsigned int val; 3462 3463 if (optlen != sizeof(val)) 3464 return -EINVAL; 3465 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 3466 return -EBUSY; 3467 if (copy_from_user(&val, optval, sizeof(val))) 3468 return -EFAULT; 3469 po->tp_loss = !!val; 3470 return 0; 3471 } 3472 case PACKET_AUXDATA: 3473 { 3474 int val; 3475 3476 if (optlen < sizeof(val)) 3477 return -EINVAL; 3478 if (copy_from_user(&val, optval, sizeof(val))) 3479 return -EFAULT; 3480 3481 po->auxdata = !!val; 3482 return 0; 3483 } 3484 case PACKET_ORIGDEV: 3485 { 3486 int val; 3487 3488 if (optlen < sizeof(val)) 3489 return -EINVAL; 3490 if (copy_from_user(&val, optval, sizeof(val))) 3491 return -EFAULT; 3492 3493 po->origdev = !!val; 3494 return 0; 3495 } 3496 case PACKET_VNET_HDR: 3497 { 3498 int val; 3499 3500 if (sock->type != SOCK_RAW) 3501 return -EINVAL; 3502 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 3503 return -EBUSY; 3504 if (optlen < sizeof(val)) 3505 return -EINVAL; 3506 if (copy_from_user(&val, optval, sizeof(val))) 3507 return -EFAULT; 3508 3509 po->has_vnet_hdr = !!val; 3510 return 0; 3511 } 3512 case PACKET_TIMESTAMP: 3513 { 3514 int val; 3515 3516 if (optlen != sizeof(val)) 3517 return -EINVAL; 3518 if (copy_from_user(&val, optval, sizeof(val))) 3519 return -EFAULT; 3520 3521 po->tp_tstamp = val; 3522 return 0; 3523 } 3524 case PACKET_FANOUT: 3525 { 3526 int val; 3527 3528 if (optlen != sizeof(val)) 3529 return -EINVAL; 3530 if (copy_from_user(&val, optval, sizeof(val))) 3531 return -EFAULT; 3532 3533 return fanout_add(sk, val & 0xffff, val >> 16); 3534 } 3535 case PACKET_TX_HAS_OFF: 3536 { 3537 unsigned int val; 3538 3539 if (optlen != sizeof(val)) 3540 return -EINVAL; 3541 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 3542 return -EBUSY; 3543 if (copy_from_user(&val, optval, sizeof(val))) 3544 return -EFAULT; 3545 po->tp_tx_has_off = !!val; 3546 return 0; 3547 } 3548 case PACKET_QDISC_BYPASS: 3549 { 3550 int val; 3551 3552 if (optlen != sizeof(val)) 3553 return -EINVAL; 3554 if (copy_from_user(&val, optval, sizeof(val))) 3555 return -EFAULT; 3556 3557 po->xmit = val ? packet_direct_xmit : dev_queue_xmit; 3558 return 0; 3559 } 3560 default: 3561 return -ENOPROTOOPT; 3562 } 3563 } 3564 3565 static int packet_getsockopt(struct socket *sock, int level, int optname, 3566 char __user *optval, int __user *optlen) 3567 { 3568 int len; 3569 int val, lv = sizeof(val); 3570 struct sock *sk = sock->sk; 3571 struct packet_sock *po = pkt_sk(sk); 3572 void *data = &val; 3573 union tpacket_stats_u st; 3574 struct tpacket_rollover_stats rstats; 3575 3576 if (level != SOL_PACKET) 3577 return -ENOPROTOOPT; 3578 3579 if (get_user(len, optlen)) 3580 return -EFAULT; 3581 3582 if (len < 0) 3583 return -EINVAL; 3584 3585 switch (optname) { 3586 case PACKET_STATISTICS: 3587 spin_lock_bh(&sk->sk_receive_queue.lock); 3588 memcpy(&st, &po->stats, sizeof(st)); 3589 memset(&po->stats, 0, sizeof(po->stats)); 3590 spin_unlock_bh(&sk->sk_receive_queue.lock); 3591 3592 if (po->tp_version == TPACKET_V3) { 3593 lv = sizeof(struct tpacket_stats_v3); 3594 st.stats3.tp_packets += st.stats3.tp_drops; 3595 data = &st.stats3; 3596 } else { 3597 lv = sizeof(struct tpacket_stats); 3598 st.stats1.tp_packets += st.stats1.tp_drops; 3599 data = &st.stats1; 3600 } 3601 3602 break; 3603 case PACKET_AUXDATA: 3604 val = po->auxdata; 3605 break; 3606 case PACKET_ORIGDEV: 3607 val = po->origdev; 3608 break; 3609 case PACKET_VNET_HDR: 3610 val = po->has_vnet_hdr; 3611 break; 3612 case PACKET_VERSION: 3613 val = po->tp_version; 3614 break; 3615 case PACKET_HDRLEN: 3616 if (len > sizeof(int)) 3617 len = sizeof(int); 3618 if (copy_from_user(&val, optval, len)) 3619 return -EFAULT; 3620 switch (val) { 3621 case TPACKET_V1: 3622 val = sizeof(struct tpacket_hdr); 3623 break; 3624 case TPACKET_V2: 3625 val = sizeof(struct tpacket2_hdr); 3626 break; 3627 case TPACKET_V3: 3628 val = sizeof(struct tpacket3_hdr); 3629 break; 3630 default: 3631 return -EINVAL; 3632 } 3633 break; 3634 case PACKET_RESERVE: 3635 val = po->tp_reserve; 3636 break; 3637 case PACKET_LOSS: 3638 val = po->tp_loss; 3639 break; 3640 case PACKET_TIMESTAMP: 3641 val = po->tp_tstamp; 3642 break; 3643 case PACKET_FANOUT: 3644 val = (po->fanout ? 3645 ((u32)po->fanout->id | 3646 ((u32)po->fanout->type << 16) | 3647 ((u32)po->fanout->flags << 24)) : 3648 0); 3649 break; 3650 case PACKET_ROLLOVER_STATS: 3651 if (!po->rollover) 3652 return -EINVAL; 3653 rstats.tp_all = atomic_long_read(&po->rollover->num); 3654 rstats.tp_huge = atomic_long_read(&po->rollover->num_huge); 3655 rstats.tp_failed = atomic_long_read(&po->rollover->num_failed); 3656 data = &rstats; 3657 lv = sizeof(rstats); 3658 break; 3659 case PACKET_TX_HAS_OFF: 3660 val = po->tp_tx_has_off; 3661 break; 3662 case PACKET_QDISC_BYPASS: 3663 val = packet_use_direct_xmit(po); 3664 break; 3665 default: 3666 return -ENOPROTOOPT; 3667 } 3668 3669 if (len > lv) 3670 len = lv; 3671 if (put_user(len, optlen)) 3672 return -EFAULT; 3673 if (copy_to_user(optval, data, len)) 3674 return -EFAULT; 3675 return 0; 3676 } 3677 3678 3679 static int packet_notifier(struct notifier_block *this, 3680 unsigned long msg, void *ptr) 3681 { 3682 struct sock *sk; 3683 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 3684 struct net *net = dev_net(dev); 3685 3686 rcu_read_lock(); 3687 sk_for_each_rcu(sk, &net->packet.sklist) { 3688 struct packet_sock *po = pkt_sk(sk); 3689 3690 switch (msg) { 3691 case NETDEV_UNREGISTER: 3692 if (po->mclist) 3693 packet_dev_mclist_delete(dev, &po->mclist); 3694 /* fallthrough */ 3695 3696 case NETDEV_DOWN: 3697 if (dev->ifindex == po->ifindex) { 3698 spin_lock(&po->bind_lock); 3699 if (po->running) { 3700 __unregister_prot_hook(sk, false); 3701 sk->sk_err = ENETDOWN; 3702 if (!sock_flag(sk, SOCK_DEAD)) 3703 sk->sk_error_report(sk); 3704 } 3705 if (msg == NETDEV_UNREGISTER) { 3706 packet_cached_dev_reset(po); 3707 po->ifindex = -1; 3708 if (po->prot_hook.dev) 3709 dev_put(po->prot_hook.dev); 3710 po->prot_hook.dev = NULL; 3711 } 3712 spin_unlock(&po->bind_lock); 3713 } 3714 break; 3715 case NETDEV_UP: 3716 if (dev->ifindex == po->ifindex) { 3717 spin_lock(&po->bind_lock); 3718 if (po->num) 3719 register_prot_hook(sk); 3720 spin_unlock(&po->bind_lock); 3721 } 3722 break; 3723 } 3724 } 3725 rcu_read_unlock(); 3726 return NOTIFY_DONE; 3727 } 3728 3729 3730 static int packet_ioctl(struct socket *sock, unsigned int cmd, 3731 unsigned long arg) 3732 { 3733 struct sock *sk = sock->sk; 3734 3735 switch (cmd) { 3736 case SIOCOUTQ: 3737 { 3738 int amount = sk_wmem_alloc_get(sk); 3739 3740 return put_user(amount, (int __user *)arg); 3741 } 3742 case SIOCINQ: 3743 { 3744 struct sk_buff *skb; 3745 int amount = 0; 3746 3747 spin_lock_bh(&sk->sk_receive_queue.lock); 3748 skb = skb_peek(&sk->sk_receive_queue); 3749 if (skb) 3750 amount = skb->len; 3751 spin_unlock_bh(&sk->sk_receive_queue.lock); 3752 return put_user(amount, (int __user *)arg); 3753 } 3754 case SIOCGSTAMP: 3755 return sock_get_timestamp(sk, (struct timeval __user *)arg); 3756 case SIOCGSTAMPNS: 3757 return sock_get_timestampns(sk, (struct timespec __user *)arg); 3758 3759 #ifdef CONFIG_INET 3760 case SIOCADDRT: 3761 case SIOCDELRT: 3762 case SIOCDARP: 3763 case SIOCGARP: 3764 case SIOCSARP: 3765 case SIOCGIFADDR: 3766 case SIOCSIFADDR: 3767 case SIOCGIFBRDADDR: 3768 case SIOCSIFBRDADDR: 3769 case SIOCGIFNETMASK: 3770 case SIOCSIFNETMASK: 3771 case SIOCGIFDSTADDR: 3772 case SIOCSIFDSTADDR: 3773 case SIOCSIFFLAGS: 3774 return inet_dgram_ops.ioctl(sock, cmd, arg); 3775 #endif 3776 3777 default: 3778 return -ENOIOCTLCMD; 3779 } 3780 return 0; 3781 } 3782 3783 static unsigned int packet_poll(struct file *file, struct socket *sock, 3784 poll_table *wait) 3785 { 3786 struct sock *sk = sock->sk; 3787 struct packet_sock *po = pkt_sk(sk); 3788 unsigned int mask = datagram_poll(file, sock, wait); 3789 3790 spin_lock_bh(&sk->sk_receive_queue.lock); 3791 if (po->rx_ring.pg_vec) { 3792 if (!packet_previous_rx_frame(po, &po->rx_ring, 3793 TP_STATUS_KERNEL)) 3794 mask |= POLLIN | POLLRDNORM; 3795 } 3796 if (po->pressure && __packet_rcv_has_room(po, NULL) == ROOM_NORMAL) 3797 po->pressure = 0; 3798 spin_unlock_bh(&sk->sk_receive_queue.lock); 3799 spin_lock_bh(&sk->sk_write_queue.lock); 3800 if (po->tx_ring.pg_vec) { 3801 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE)) 3802 mask |= POLLOUT | POLLWRNORM; 3803 } 3804 spin_unlock_bh(&sk->sk_write_queue.lock); 3805 return mask; 3806 } 3807 3808 3809 /* Dirty? Well, I still did not learn better way to account 3810 * for user mmaps. 3811 */ 3812 3813 static void packet_mm_open(struct vm_area_struct *vma) 3814 { 3815 struct file *file = vma->vm_file; 3816 struct socket *sock = file->private_data; 3817 struct sock *sk = sock->sk; 3818 3819 if (sk) 3820 atomic_inc(&pkt_sk(sk)->mapped); 3821 } 3822 3823 static void packet_mm_close(struct vm_area_struct *vma) 3824 { 3825 struct file *file = vma->vm_file; 3826 struct socket *sock = file->private_data; 3827 struct sock *sk = sock->sk; 3828 3829 if (sk) 3830 atomic_dec(&pkt_sk(sk)->mapped); 3831 } 3832 3833 static const struct vm_operations_struct packet_mmap_ops = { 3834 .open = packet_mm_open, 3835 .close = packet_mm_close, 3836 }; 3837 3838 static void free_pg_vec(struct pgv *pg_vec, unsigned int order, 3839 unsigned int len) 3840 { 3841 int i; 3842 3843 for (i = 0; i < len; i++) { 3844 if (likely(pg_vec[i].buffer)) { 3845 if (is_vmalloc_addr(pg_vec[i].buffer)) 3846 vfree(pg_vec[i].buffer); 3847 else 3848 free_pages((unsigned long)pg_vec[i].buffer, 3849 order); 3850 pg_vec[i].buffer = NULL; 3851 } 3852 } 3853 kfree(pg_vec); 3854 } 3855 3856 static char *alloc_one_pg_vec_page(unsigned long order) 3857 { 3858 char *buffer; 3859 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP | 3860 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY; 3861 3862 buffer = (char *) __get_free_pages(gfp_flags, order); 3863 if (buffer) 3864 return buffer; 3865 3866 /* __get_free_pages failed, fall back to vmalloc */ 3867 buffer = vzalloc((1 << order) * PAGE_SIZE); 3868 if (buffer) 3869 return buffer; 3870 3871 /* vmalloc failed, lets dig into swap here */ 3872 gfp_flags &= ~__GFP_NORETRY; 3873 buffer = (char *) __get_free_pages(gfp_flags, order); 3874 if (buffer) 3875 return buffer; 3876 3877 /* complete and utter failure */ 3878 return NULL; 3879 } 3880 3881 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order) 3882 { 3883 unsigned int block_nr = req->tp_block_nr; 3884 struct pgv *pg_vec; 3885 int i; 3886 3887 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL); 3888 if (unlikely(!pg_vec)) 3889 goto out; 3890 3891 for (i = 0; i < block_nr; i++) { 3892 pg_vec[i].buffer = alloc_one_pg_vec_page(order); 3893 if (unlikely(!pg_vec[i].buffer)) 3894 goto out_free_pgvec; 3895 } 3896 3897 out: 3898 return pg_vec; 3899 3900 out_free_pgvec: 3901 free_pg_vec(pg_vec, order, block_nr); 3902 pg_vec = NULL; 3903 goto out; 3904 } 3905 3906 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u, 3907 int closing, int tx_ring) 3908 { 3909 struct pgv *pg_vec = NULL; 3910 struct packet_sock *po = pkt_sk(sk); 3911 int was_running, order = 0; 3912 struct packet_ring_buffer *rb; 3913 struct sk_buff_head *rb_queue; 3914 __be16 num; 3915 int err = -EINVAL; 3916 /* Added to avoid minimal code churn */ 3917 struct tpacket_req *req = &req_u->req; 3918 3919 /* Opening a Tx-ring is NOT supported in TPACKET_V3 */ 3920 if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) { 3921 WARN(1, "Tx-ring is not supported.\n"); 3922 goto out; 3923 } 3924 3925 rb = tx_ring ? &po->tx_ring : &po->rx_ring; 3926 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue; 3927 3928 err = -EBUSY; 3929 if (!closing) { 3930 if (atomic_read(&po->mapped)) 3931 goto out; 3932 if (packet_read_pending(rb)) 3933 goto out; 3934 } 3935 3936 if (req->tp_block_nr) { 3937 /* Sanity tests and some calculations */ 3938 err = -EBUSY; 3939 if (unlikely(rb->pg_vec)) 3940 goto out; 3941 3942 switch (po->tp_version) { 3943 case TPACKET_V1: 3944 po->tp_hdrlen = TPACKET_HDRLEN; 3945 break; 3946 case TPACKET_V2: 3947 po->tp_hdrlen = TPACKET2_HDRLEN; 3948 break; 3949 case TPACKET_V3: 3950 po->tp_hdrlen = TPACKET3_HDRLEN; 3951 break; 3952 } 3953 3954 err = -EINVAL; 3955 if (unlikely((int)req->tp_block_size <= 0)) 3956 goto out; 3957 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1))) 3958 goto out; 3959 if (po->tp_version >= TPACKET_V3 && 3960 (int)(req->tp_block_size - 3961 BLK_PLUS_PRIV(req_u->req3.tp_sizeof_priv)) <= 0) 3962 goto out; 3963 if (unlikely(req->tp_frame_size < po->tp_hdrlen + 3964 po->tp_reserve)) 3965 goto out; 3966 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1))) 3967 goto out; 3968 3969 rb->frames_per_block = req->tp_block_size/req->tp_frame_size; 3970 if (unlikely(rb->frames_per_block <= 0)) 3971 goto out; 3972 if (unlikely((rb->frames_per_block * req->tp_block_nr) != 3973 req->tp_frame_nr)) 3974 goto out; 3975 3976 err = -ENOMEM; 3977 order = get_order(req->tp_block_size); 3978 pg_vec = alloc_pg_vec(req, order); 3979 if (unlikely(!pg_vec)) 3980 goto out; 3981 switch (po->tp_version) { 3982 case TPACKET_V3: 3983 /* Transmit path is not supported. We checked 3984 * it above but just being paranoid 3985 */ 3986 if (!tx_ring) 3987 init_prb_bdqc(po, rb, pg_vec, req_u); 3988 break; 3989 default: 3990 break; 3991 } 3992 } 3993 /* Done */ 3994 else { 3995 err = -EINVAL; 3996 if (unlikely(req->tp_frame_nr)) 3997 goto out; 3998 } 3999 4000 lock_sock(sk); 4001 4002 /* Detach socket from network */ 4003 spin_lock(&po->bind_lock); 4004 was_running = po->running; 4005 num = po->num; 4006 if (was_running) { 4007 po->num = 0; 4008 __unregister_prot_hook(sk, false); 4009 } 4010 spin_unlock(&po->bind_lock); 4011 4012 synchronize_net(); 4013 4014 err = -EBUSY; 4015 mutex_lock(&po->pg_vec_lock); 4016 if (closing || atomic_read(&po->mapped) == 0) { 4017 err = 0; 4018 spin_lock_bh(&rb_queue->lock); 4019 swap(rb->pg_vec, pg_vec); 4020 rb->frame_max = (req->tp_frame_nr - 1); 4021 rb->head = 0; 4022 rb->frame_size = req->tp_frame_size; 4023 spin_unlock_bh(&rb_queue->lock); 4024 4025 swap(rb->pg_vec_order, order); 4026 swap(rb->pg_vec_len, req->tp_block_nr); 4027 4028 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE; 4029 po->prot_hook.func = (po->rx_ring.pg_vec) ? 4030 tpacket_rcv : packet_rcv; 4031 skb_queue_purge(rb_queue); 4032 if (atomic_read(&po->mapped)) 4033 pr_err("packet_mmap: vma is busy: %d\n", 4034 atomic_read(&po->mapped)); 4035 } 4036 mutex_unlock(&po->pg_vec_lock); 4037 4038 spin_lock(&po->bind_lock); 4039 if (was_running) { 4040 po->num = num; 4041 register_prot_hook(sk); 4042 } 4043 spin_unlock(&po->bind_lock); 4044 if (closing && (po->tp_version > TPACKET_V2)) { 4045 /* Because we don't support block-based V3 on tx-ring */ 4046 if (!tx_ring) 4047 prb_shutdown_retire_blk_timer(po, tx_ring, rb_queue); 4048 } 4049 release_sock(sk); 4050 4051 if (pg_vec) 4052 free_pg_vec(pg_vec, order, req->tp_block_nr); 4053 out: 4054 return err; 4055 } 4056 4057 static int packet_mmap(struct file *file, struct socket *sock, 4058 struct vm_area_struct *vma) 4059 { 4060 struct sock *sk = sock->sk; 4061 struct packet_sock *po = pkt_sk(sk); 4062 unsigned long size, expected_size; 4063 struct packet_ring_buffer *rb; 4064 unsigned long start; 4065 int err = -EINVAL; 4066 int i; 4067 4068 if (vma->vm_pgoff) 4069 return -EINVAL; 4070 4071 mutex_lock(&po->pg_vec_lock); 4072 4073 expected_size = 0; 4074 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) { 4075 if (rb->pg_vec) { 4076 expected_size += rb->pg_vec_len 4077 * rb->pg_vec_pages 4078 * PAGE_SIZE; 4079 } 4080 } 4081 4082 if (expected_size == 0) 4083 goto out; 4084 4085 size = vma->vm_end - vma->vm_start; 4086 if (size != expected_size) 4087 goto out; 4088 4089 start = vma->vm_start; 4090 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) { 4091 if (rb->pg_vec == NULL) 4092 continue; 4093 4094 for (i = 0; i < rb->pg_vec_len; i++) { 4095 struct page *page; 4096 void *kaddr = rb->pg_vec[i].buffer; 4097 int pg_num; 4098 4099 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) { 4100 page = pgv_to_page(kaddr); 4101 err = vm_insert_page(vma, start, page); 4102 if (unlikely(err)) 4103 goto out; 4104 start += PAGE_SIZE; 4105 kaddr += PAGE_SIZE; 4106 } 4107 } 4108 } 4109 4110 atomic_inc(&po->mapped); 4111 vma->vm_ops = &packet_mmap_ops; 4112 err = 0; 4113 4114 out: 4115 mutex_unlock(&po->pg_vec_lock); 4116 return err; 4117 } 4118 4119 static const struct proto_ops packet_ops_spkt = { 4120 .family = PF_PACKET, 4121 .owner = THIS_MODULE, 4122 .release = packet_release, 4123 .bind = packet_bind_spkt, 4124 .connect = sock_no_connect, 4125 .socketpair = sock_no_socketpair, 4126 .accept = sock_no_accept, 4127 .getname = packet_getname_spkt, 4128 .poll = datagram_poll, 4129 .ioctl = packet_ioctl, 4130 .listen = sock_no_listen, 4131 .shutdown = sock_no_shutdown, 4132 .setsockopt = sock_no_setsockopt, 4133 .getsockopt = sock_no_getsockopt, 4134 .sendmsg = packet_sendmsg_spkt, 4135 .recvmsg = packet_recvmsg, 4136 .mmap = sock_no_mmap, 4137 .sendpage = sock_no_sendpage, 4138 }; 4139 4140 static const struct proto_ops packet_ops = { 4141 .family = PF_PACKET, 4142 .owner = THIS_MODULE, 4143 .release = packet_release, 4144 .bind = packet_bind, 4145 .connect = sock_no_connect, 4146 .socketpair = sock_no_socketpair, 4147 .accept = sock_no_accept, 4148 .getname = packet_getname, 4149 .poll = packet_poll, 4150 .ioctl = packet_ioctl, 4151 .listen = sock_no_listen, 4152 .shutdown = sock_no_shutdown, 4153 .setsockopt = packet_setsockopt, 4154 .getsockopt = packet_getsockopt, 4155 .sendmsg = packet_sendmsg, 4156 .recvmsg = packet_recvmsg, 4157 .mmap = packet_mmap, 4158 .sendpage = sock_no_sendpage, 4159 }; 4160 4161 static const struct net_proto_family packet_family_ops = { 4162 .family = PF_PACKET, 4163 .create = packet_create, 4164 .owner = THIS_MODULE, 4165 }; 4166 4167 static struct notifier_block packet_netdev_notifier = { 4168 .notifier_call = packet_notifier, 4169 }; 4170 4171 #ifdef CONFIG_PROC_FS 4172 4173 static void *packet_seq_start(struct seq_file *seq, loff_t *pos) 4174 __acquires(RCU) 4175 { 4176 struct net *net = seq_file_net(seq); 4177 4178 rcu_read_lock(); 4179 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos); 4180 } 4181 4182 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos) 4183 { 4184 struct net *net = seq_file_net(seq); 4185 return seq_hlist_next_rcu(v, &net->packet.sklist, pos); 4186 } 4187 4188 static void packet_seq_stop(struct seq_file *seq, void *v) 4189 __releases(RCU) 4190 { 4191 rcu_read_unlock(); 4192 } 4193 4194 static int packet_seq_show(struct seq_file *seq, void *v) 4195 { 4196 if (v == SEQ_START_TOKEN) 4197 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n"); 4198 else { 4199 struct sock *s = sk_entry(v); 4200 const struct packet_sock *po = pkt_sk(s); 4201 4202 seq_printf(seq, 4203 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n", 4204 s, 4205 atomic_read(&s->sk_refcnt), 4206 s->sk_type, 4207 ntohs(po->num), 4208 po->ifindex, 4209 po->running, 4210 atomic_read(&s->sk_rmem_alloc), 4211 from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)), 4212 sock_i_ino(s)); 4213 } 4214 4215 return 0; 4216 } 4217 4218 static const struct seq_operations packet_seq_ops = { 4219 .start = packet_seq_start, 4220 .next = packet_seq_next, 4221 .stop = packet_seq_stop, 4222 .show = packet_seq_show, 4223 }; 4224 4225 static int packet_seq_open(struct inode *inode, struct file *file) 4226 { 4227 return seq_open_net(inode, file, &packet_seq_ops, 4228 sizeof(struct seq_net_private)); 4229 } 4230 4231 static const struct file_operations packet_seq_fops = { 4232 .owner = THIS_MODULE, 4233 .open = packet_seq_open, 4234 .read = seq_read, 4235 .llseek = seq_lseek, 4236 .release = seq_release_net, 4237 }; 4238 4239 #endif 4240 4241 static int __net_init packet_net_init(struct net *net) 4242 { 4243 mutex_init(&net->packet.sklist_lock); 4244 INIT_HLIST_HEAD(&net->packet.sklist); 4245 4246 if (!proc_create("packet", 0, net->proc_net, &packet_seq_fops)) 4247 return -ENOMEM; 4248 4249 return 0; 4250 } 4251 4252 static void __net_exit packet_net_exit(struct net *net) 4253 { 4254 remove_proc_entry("packet", net->proc_net); 4255 } 4256 4257 static struct pernet_operations packet_net_ops = { 4258 .init = packet_net_init, 4259 .exit = packet_net_exit, 4260 }; 4261 4262 4263 static void __exit packet_exit(void) 4264 { 4265 unregister_netdevice_notifier(&packet_netdev_notifier); 4266 unregister_pernet_subsys(&packet_net_ops); 4267 sock_unregister(PF_PACKET); 4268 proto_unregister(&packet_proto); 4269 } 4270 4271 static int __init packet_init(void) 4272 { 4273 int rc = proto_register(&packet_proto, 0); 4274 4275 if (rc != 0) 4276 goto out; 4277 4278 sock_register(&packet_family_ops); 4279 register_pernet_subsys(&packet_net_ops); 4280 register_netdevice_notifier(&packet_netdev_notifier); 4281 out: 4282 return rc; 4283 } 4284 4285 module_init(packet_init); 4286 module_exit(packet_exit); 4287 MODULE_LICENSE("GPL"); 4288 MODULE_ALIAS_NETPROTO(PF_PACKET); 4289