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 * 44 * This program is free software; you can redistribute it and/or 45 * modify it under the terms of the GNU General Public License 46 * as published by the Free Software Foundation; either version 47 * 2 of the License, or (at your option) any later version. 48 * 49 */ 50 51 #include <linux/types.h> 52 #include <linux/mm.h> 53 #include <linux/capability.h> 54 #include <linux/fcntl.h> 55 #include <linux/socket.h> 56 #include <linux/in.h> 57 #include <linux/inet.h> 58 #include <linux/netdevice.h> 59 #include <linux/if_packet.h> 60 #include <linux/wireless.h> 61 #include <linux/kernel.h> 62 #include <linux/kmod.h> 63 #include <linux/slab.h> 64 #include <linux/vmalloc.h> 65 #include <net/net_namespace.h> 66 #include <net/ip.h> 67 #include <net/protocol.h> 68 #include <linux/skbuff.h> 69 #include <net/sock.h> 70 #include <linux/errno.h> 71 #include <linux/timer.h> 72 #include <asm/system.h> 73 #include <asm/uaccess.h> 74 #include <asm/ioctls.h> 75 #include <asm/page.h> 76 #include <asm/cacheflush.h> 77 #include <asm/io.h> 78 #include <linux/proc_fs.h> 79 #include <linux/seq_file.h> 80 #include <linux/poll.h> 81 #include <linux/module.h> 82 #include <linux/init.h> 83 #include <linux/mutex.h> 84 #include <linux/if_vlan.h> 85 #include <linux/virtio_net.h> 86 #include <linux/errqueue.h> 87 #include <linux/net_tstamp.h> 88 89 #ifdef CONFIG_INET 90 #include <net/inet_common.h> 91 #endif 92 93 /* 94 Assumptions: 95 - if device has no dev->hard_header routine, it adds and removes ll header 96 inside itself. In this case ll header is invisible outside of device, 97 but higher levels still should reserve dev->hard_header_len. 98 Some devices are enough clever to reallocate skb, when header 99 will not fit to reserved space (tunnel), another ones are silly 100 (PPP). 101 - packet socket receives packets with pulled ll header, 102 so that SOCK_RAW should push it back. 103 104 On receive: 105 ----------- 106 107 Incoming, dev->hard_header!=NULL 108 mac_header -> ll header 109 data -> data 110 111 Outgoing, dev->hard_header!=NULL 112 mac_header -> ll header 113 data -> ll header 114 115 Incoming, dev->hard_header==NULL 116 mac_header -> UNKNOWN position. It is very likely, that it points to ll 117 header. PPP makes it, that is wrong, because introduce 118 assymetry between rx and tx paths. 119 data -> data 120 121 Outgoing, dev->hard_header==NULL 122 mac_header -> data. ll header is still not built! 123 data -> data 124 125 Resume 126 If dev->hard_header==NULL we are unlikely to restore sensible ll header. 127 128 129 On transmit: 130 ------------ 131 132 dev->hard_header != NULL 133 mac_header -> ll header 134 data -> ll header 135 136 dev->hard_header == NULL (ll header is added by device, we cannot control it) 137 mac_header -> data 138 data -> data 139 140 We should set nh.raw on output to correct posistion, 141 packet classifier depends on it. 142 */ 143 144 /* Private packet socket structures. */ 145 146 struct packet_mclist { 147 struct packet_mclist *next; 148 int ifindex; 149 int count; 150 unsigned short type; 151 unsigned short alen; 152 unsigned char addr[MAX_ADDR_LEN]; 153 }; 154 /* identical to struct packet_mreq except it has 155 * a longer address field. 156 */ 157 struct packet_mreq_max { 158 int mr_ifindex; 159 unsigned short mr_type; 160 unsigned short mr_alen; 161 unsigned char mr_address[MAX_ADDR_LEN]; 162 }; 163 164 static int packet_set_ring(struct sock *sk, struct tpacket_req *req, 165 int closing, int tx_ring); 166 167 struct pgv { 168 char *buffer; 169 }; 170 171 struct packet_ring_buffer { 172 struct pgv *pg_vec; 173 unsigned int head; 174 unsigned int frames_per_block; 175 unsigned int frame_size; 176 unsigned int frame_max; 177 178 unsigned int pg_vec_order; 179 unsigned int pg_vec_pages; 180 unsigned int pg_vec_len; 181 182 atomic_t pending; 183 }; 184 185 struct packet_sock; 186 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg); 187 188 static void packet_flush_mclist(struct sock *sk); 189 190 struct packet_sock { 191 /* struct sock has to be the first member of packet_sock */ 192 struct sock sk; 193 struct tpacket_stats stats; 194 struct packet_ring_buffer rx_ring; 195 struct packet_ring_buffer tx_ring; 196 int copy_thresh; 197 spinlock_t bind_lock; 198 struct mutex pg_vec_lock; 199 unsigned int running:1, /* prot_hook is attached*/ 200 auxdata:1, 201 origdev:1, 202 has_vnet_hdr:1; 203 int ifindex; /* bound device */ 204 __be16 num; 205 struct packet_mclist *mclist; 206 atomic_t mapped; 207 enum tpacket_versions tp_version; 208 unsigned int tp_hdrlen; 209 unsigned int tp_reserve; 210 unsigned int tp_loss:1; 211 unsigned int tp_tstamp; 212 struct packet_type prot_hook ____cacheline_aligned_in_smp; 213 }; 214 215 struct packet_skb_cb { 216 unsigned int origlen; 217 union { 218 struct sockaddr_pkt pkt; 219 struct sockaddr_ll ll; 220 } sa; 221 }; 222 223 #define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb)) 224 225 static inline __pure struct page *pgv_to_page(void *addr) 226 { 227 if (is_vmalloc_addr(addr)) 228 return vmalloc_to_page(addr); 229 return virt_to_page(addr); 230 } 231 232 static void __packet_set_status(struct packet_sock *po, void *frame, int status) 233 { 234 union { 235 struct tpacket_hdr *h1; 236 struct tpacket2_hdr *h2; 237 void *raw; 238 } h; 239 240 h.raw = frame; 241 switch (po->tp_version) { 242 case TPACKET_V1: 243 h.h1->tp_status = status; 244 flush_dcache_page(pgv_to_page(&h.h1->tp_status)); 245 break; 246 case TPACKET_V2: 247 h.h2->tp_status = status; 248 flush_dcache_page(pgv_to_page(&h.h2->tp_status)); 249 break; 250 default: 251 pr_err("TPACKET version not supported\n"); 252 BUG(); 253 } 254 255 smp_wmb(); 256 } 257 258 static int __packet_get_status(struct packet_sock *po, void *frame) 259 { 260 union { 261 struct tpacket_hdr *h1; 262 struct tpacket2_hdr *h2; 263 void *raw; 264 } h; 265 266 smp_rmb(); 267 268 h.raw = frame; 269 switch (po->tp_version) { 270 case TPACKET_V1: 271 flush_dcache_page(pgv_to_page(&h.h1->tp_status)); 272 return h.h1->tp_status; 273 case TPACKET_V2: 274 flush_dcache_page(pgv_to_page(&h.h2->tp_status)); 275 return h.h2->tp_status; 276 default: 277 pr_err("TPACKET version not supported\n"); 278 BUG(); 279 return 0; 280 } 281 } 282 283 static void *packet_lookup_frame(struct packet_sock *po, 284 struct packet_ring_buffer *rb, 285 unsigned int position, 286 int status) 287 { 288 unsigned int pg_vec_pos, frame_offset; 289 union { 290 struct tpacket_hdr *h1; 291 struct tpacket2_hdr *h2; 292 void *raw; 293 } h; 294 295 pg_vec_pos = position / rb->frames_per_block; 296 frame_offset = position % rb->frames_per_block; 297 298 h.raw = rb->pg_vec[pg_vec_pos].buffer + 299 (frame_offset * rb->frame_size); 300 301 if (status != __packet_get_status(po, h.raw)) 302 return NULL; 303 304 return h.raw; 305 } 306 307 static inline void *packet_current_frame(struct packet_sock *po, 308 struct packet_ring_buffer *rb, 309 int status) 310 { 311 return packet_lookup_frame(po, rb, rb->head, status); 312 } 313 314 static inline void *packet_previous_frame(struct packet_sock *po, 315 struct packet_ring_buffer *rb, 316 int status) 317 { 318 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max; 319 return packet_lookup_frame(po, rb, previous, status); 320 } 321 322 static inline void packet_increment_head(struct packet_ring_buffer *buff) 323 { 324 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0; 325 } 326 327 static inline struct packet_sock *pkt_sk(struct sock *sk) 328 { 329 return (struct packet_sock *)sk; 330 } 331 332 static void packet_sock_destruct(struct sock *sk) 333 { 334 skb_queue_purge(&sk->sk_error_queue); 335 336 WARN_ON(atomic_read(&sk->sk_rmem_alloc)); 337 WARN_ON(atomic_read(&sk->sk_wmem_alloc)); 338 339 if (!sock_flag(sk, SOCK_DEAD)) { 340 pr_err("Attempt to release alive packet socket: %p\n", sk); 341 return; 342 } 343 344 sk_refcnt_debug_dec(sk); 345 } 346 347 348 static const struct proto_ops packet_ops; 349 350 static const struct proto_ops packet_ops_spkt; 351 352 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev, 353 struct packet_type *pt, struct net_device *orig_dev) 354 { 355 struct sock *sk; 356 struct sockaddr_pkt *spkt; 357 358 /* 359 * When we registered the protocol we saved the socket in the data 360 * field for just this event. 361 */ 362 363 sk = pt->af_packet_priv; 364 365 /* 366 * Yank back the headers [hope the device set this 367 * right or kerboom...] 368 * 369 * Incoming packets have ll header pulled, 370 * push it back. 371 * 372 * For outgoing ones skb->data == skb_mac_header(skb) 373 * so that this procedure is noop. 374 */ 375 376 if (skb->pkt_type == PACKET_LOOPBACK) 377 goto out; 378 379 if (!net_eq(dev_net(dev), sock_net(sk))) 380 goto out; 381 382 skb = skb_share_check(skb, GFP_ATOMIC); 383 if (skb == NULL) 384 goto oom; 385 386 /* drop any routing info */ 387 skb_dst_drop(skb); 388 389 /* drop conntrack reference */ 390 nf_reset(skb); 391 392 spkt = &PACKET_SKB_CB(skb)->sa.pkt; 393 394 skb_push(skb, skb->data - skb_mac_header(skb)); 395 396 /* 397 * The SOCK_PACKET socket receives _all_ frames. 398 */ 399 400 spkt->spkt_family = dev->type; 401 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device)); 402 spkt->spkt_protocol = skb->protocol; 403 404 /* 405 * Charge the memory to the socket. This is done specifically 406 * to prevent sockets using all the memory up. 407 */ 408 409 if (sock_queue_rcv_skb(sk, skb) == 0) 410 return 0; 411 412 out: 413 kfree_skb(skb); 414 oom: 415 return 0; 416 } 417 418 419 /* 420 * Output a raw packet to a device layer. This bypasses all the other 421 * protocol layers and you must therefore supply it with a complete frame 422 */ 423 424 static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock, 425 struct msghdr *msg, size_t len) 426 { 427 struct sock *sk = sock->sk; 428 struct sockaddr_pkt *saddr = (struct sockaddr_pkt *)msg->msg_name; 429 struct sk_buff *skb = NULL; 430 struct net_device *dev; 431 __be16 proto = 0; 432 int err; 433 434 /* 435 * Get and verify the address. 436 */ 437 438 if (saddr) { 439 if (msg->msg_namelen < sizeof(struct sockaddr)) 440 return -EINVAL; 441 if (msg->msg_namelen == sizeof(struct sockaddr_pkt)) 442 proto = saddr->spkt_protocol; 443 } else 444 return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */ 445 446 /* 447 * Find the device first to size check it 448 */ 449 450 saddr->spkt_device[13] = 0; 451 retry: 452 rcu_read_lock(); 453 dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device); 454 err = -ENODEV; 455 if (dev == NULL) 456 goto out_unlock; 457 458 err = -ENETDOWN; 459 if (!(dev->flags & IFF_UP)) 460 goto out_unlock; 461 462 /* 463 * You may not queue a frame bigger than the mtu. This is the lowest level 464 * raw protocol and you must do your own fragmentation at this level. 465 */ 466 467 err = -EMSGSIZE; 468 if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN) 469 goto out_unlock; 470 471 if (!skb) { 472 size_t reserved = LL_RESERVED_SPACE(dev); 473 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0; 474 475 rcu_read_unlock(); 476 skb = sock_wmalloc(sk, len + reserved, 0, GFP_KERNEL); 477 if (skb == NULL) 478 return -ENOBUFS; 479 /* FIXME: Save some space for broken drivers that write a hard 480 * header at transmission time by themselves. PPP is the notable 481 * one here. This should really be fixed at the driver level. 482 */ 483 skb_reserve(skb, reserved); 484 skb_reset_network_header(skb); 485 486 /* Try to align data part correctly */ 487 if (hhlen) { 488 skb->data -= hhlen; 489 skb->tail -= hhlen; 490 if (len < hhlen) 491 skb_reset_network_header(skb); 492 } 493 err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len); 494 if (err) 495 goto out_free; 496 goto retry; 497 } 498 499 if (len > (dev->mtu + dev->hard_header_len)) { 500 /* Earlier code assumed this would be a VLAN pkt, 501 * double-check this now that we have the actual 502 * packet in hand. 503 */ 504 struct ethhdr *ehdr; 505 skb_reset_mac_header(skb); 506 ehdr = eth_hdr(skb); 507 if (ehdr->h_proto != htons(ETH_P_8021Q)) { 508 err = -EMSGSIZE; 509 goto out_unlock; 510 } 511 } 512 513 skb->protocol = proto; 514 skb->dev = dev; 515 skb->priority = sk->sk_priority; 516 skb->mark = sk->sk_mark; 517 err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags); 518 if (err < 0) 519 goto out_unlock; 520 521 dev_queue_xmit(skb); 522 rcu_read_unlock(); 523 return len; 524 525 out_unlock: 526 rcu_read_unlock(); 527 out_free: 528 kfree_skb(skb); 529 return err; 530 } 531 532 static inline unsigned int run_filter(const struct sk_buff *skb, 533 const struct sock *sk, 534 unsigned int res) 535 { 536 struct sk_filter *filter; 537 538 rcu_read_lock(); 539 filter = rcu_dereference(sk->sk_filter); 540 if (filter != NULL) 541 res = SK_RUN_FILTER(filter, skb); 542 rcu_read_unlock(); 543 544 return res; 545 } 546 547 /* 548 * This function makes lazy skb cloning in hope that most of packets 549 * are discarded by BPF. 550 * 551 * Note tricky part: we DO mangle shared skb! skb->data, skb->len 552 * and skb->cb are mangled. It works because (and until) packets 553 * falling here are owned by current CPU. Output packets are cloned 554 * by dev_queue_xmit_nit(), input packets are processed by net_bh 555 * sequencially, so that if we return skb to original state on exit, 556 * we will not harm anyone. 557 */ 558 559 static int packet_rcv(struct sk_buff *skb, struct net_device *dev, 560 struct packet_type *pt, struct net_device *orig_dev) 561 { 562 struct sock *sk; 563 struct sockaddr_ll *sll; 564 struct packet_sock *po; 565 u8 *skb_head = skb->data; 566 int skb_len = skb->len; 567 unsigned int snaplen, res; 568 569 if (skb->pkt_type == PACKET_LOOPBACK) 570 goto drop; 571 572 sk = pt->af_packet_priv; 573 po = pkt_sk(sk); 574 575 if (!net_eq(dev_net(dev), sock_net(sk))) 576 goto drop; 577 578 skb->dev = dev; 579 580 if (dev->header_ops) { 581 /* The device has an explicit notion of ll header, 582 * exported to higher levels. 583 * 584 * Otherwise, the device hides details of its frame 585 * structure, so that corresponding packet head is 586 * never delivered to user. 587 */ 588 if (sk->sk_type != SOCK_DGRAM) 589 skb_push(skb, skb->data - skb_mac_header(skb)); 590 else if (skb->pkt_type == PACKET_OUTGOING) { 591 /* Special case: outgoing packets have ll header at head */ 592 skb_pull(skb, skb_network_offset(skb)); 593 } 594 } 595 596 snaplen = skb->len; 597 598 res = run_filter(skb, sk, snaplen); 599 if (!res) 600 goto drop_n_restore; 601 if (snaplen > res) 602 snaplen = res; 603 604 if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >= 605 (unsigned)sk->sk_rcvbuf) 606 goto drop_n_acct; 607 608 if (skb_shared(skb)) { 609 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC); 610 if (nskb == NULL) 611 goto drop_n_acct; 612 613 if (skb_head != skb->data) { 614 skb->data = skb_head; 615 skb->len = skb_len; 616 } 617 kfree_skb(skb); 618 skb = nskb; 619 } 620 621 BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 > 622 sizeof(skb->cb)); 623 624 sll = &PACKET_SKB_CB(skb)->sa.ll; 625 sll->sll_family = AF_PACKET; 626 sll->sll_hatype = dev->type; 627 sll->sll_protocol = skb->protocol; 628 sll->sll_pkttype = skb->pkt_type; 629 if (unlikely(po->origdev)) 630 sll->sll_ifindex = orig_dev->ifindex; 631 else 632 sll->sll_ifindex = dev->ifindex; 633 634 sll->sll_halen = dev_parse_header(skb, sll->sll_addr); 635 636 PACKET_SKB_CB(skb)->origlen = skb->len; 637 638 if (pskb_trim(skb, snaplen)) 639 goto drop_n_acct; 640 641 skb_set_owner_r(skb, sk); 642 skb->dev = NULL; 643 skb_dst_drop(skb); 644 645 /* drop conntrack reference */ 646 nf_reset(skb); 647 648 spin_lock(&sk->sk_receive_queue.lock); 649 po->stats.tp_packets++; 650 skb->dropcount = atomic_read(&sk->sk_drops); 651 __skb_queue_tail(&sk->sk_receive_queue, skb); 652 spin_unlock(&sk->sk_receive_queue.lock); 653 sk->sk_data_ready(sk, skb->len); 654 return 0; 655 656 drop_n_acct: 657 po->stats.tp_drops = atomic_inc_return(&sk->sk_drops); 658 659 drop_n_restore: 660 if (skb_head != skb->data && skb_shared(skb)) { 661 skb->data = skb_head; 662 skb->len = skb_len; 663 } 664 drop: 665 consume_skb(skb); 666 return 0; 667 } 668 669 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, 670 struct packet_type *pt, struct net_device *orig_dev) 671 { 672 struct sock *sk; 673 struct packet_sock *po; 674 struct sockaddr_ll *sll; 675 union { 676 struct tpacket_hdr *h1; 677 struct tpacket2_hdr *h2; 678 void *raw; 679 } h; 680 u8 *skb_head = skb->data; 681 int skb_len = skb->len; 682 unsigned int snaplen, res; 683 unsigned long status = TP_STATUS_LOSING|TP_STATUS_USER; 684 unsigned short macoff, netoff, hdrlen; 685 struct sk_buff *copy_skb = NULL; 686 struct timeval tv; 687 struct timespec ts; 688 struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb); 689 690 if (skb->pkt_type == PACKET_LOOPBACK) 691 goto drop; 692 693 sk = pt->af_packet_priv; 694 po = pkt_sk(sk); 695 696 if (!net_eq(dev_net(dev), sock_net(sk))) 697 goto drop; 698 699 if (dev->header_ops) { 700 if (sk->sk_type != SOCK_DGRAM) 701 skb_push(skb, skb->data - skb_mac_header(skb)); 702 else if (skb->pkt_type == PACKET_OUTGOING) { 703 /* Special case: outgoing packets have ll header at head */ 704 skb_pull(skb, skb_network_offset(skb)); 705 } 706 } 707 708 if (skb->ip_summed == CHECKSUM_PARTIAL) 709 status |= TP_STATUS_CSUMNOTREADY; 710 711 snaplen = skb->len; 712 713 res = run_filter(skb, sk, snaplen); 714 if (!res) 715 goto drop_n_restore; 716 if (snaplen > res) 717 snaplen = res; 718 719 if (sk->sk_type == SOCK_DGRAM) { 720 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 + 721 po->tp_reserve; 722 } else { 723 unsigned maclen = skb_network_offset(skb); 724 netoff = TPACKET_ALIGN(po->tp_hdrlen + 725 (maclen < 16 ? 16 : maclen)) + 726 po->tp_reserve; 727 macoff = netoff - maclen; 728 } 729 730 if (macoff + snaplen > po->rx_ring.frame_size) { 731 if (po->copy_thresh && 732 atomic_read(&sk->sk_rmem_alloc) + skb->truesize < 733 (unsigned)sk->sk_rcvbuf) { 734 if (skb_shared(skb)) { 735 copy_skb = skb_clone(skb, GFP_ATOMIC); 736 } else { 737 copy_skb = skb_get(skb); 738 skb_head = skb->data; 739 } 740 if (copy_skb) 741 skb_set_owner_r(copy_skb, sk); 742 } 743 snaplen = po->rx_ring.frame_size - macoff; 744 if ((int)snaplen < 0) 745 snaplen = 0; 746 } 747 748 spin_lock(&sk->sk_receive_queue.lock); 749 h.raw = packet_current_frame(po, &po->rx_ring, TP_STATUS_KERNEL); 750 if (!h.raw) 751 goto ring_is_full; 752 packet_increment_head(&po->rx_ring); 753 po->stats.tp_packets++; 754 if (copy_skb) { 755 status |= TP_STATUS_COPY; 756 __skb_queue_tail(&sk->sk_receive_queue, copy_skb); 757 } 758 if (!po->stats.tp_drops) 759 status &= ~TP_STATUS_LOSING; 760 spin_unlock(&sk->sk_receive_queue.lock); 761 762 skb_copy_bits(skb, 0, h.raw + macoff, snaplen); 763 764 switch (po->tp_version) { 765 case TPACKET_V1: 766 h.h1->tp_len = skb->len; 767 h.h1->tp_snaplen = snaplen; 768 h.h1->tp_mac = macoff; 769 h.h1->tp_net = netoff; 770 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE) 771 && shhwtstamps->syststamp.tv64) 772 tv = ktime_to_timeval(shhwtstamps->syststamp); 773 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE) 774 && shhwtstamps->hwtstamp.tv64) 775 tv = ktime_to_timeval(shhwtstamps->hwtstamp); 776 else if (skb->tstamp.tv64) 777 tv = ktime_to_timeval(skb->tstamp); 778 else 779 do_gettimeofday(&tv); 780 h.h1->tp_sec = tv.tv_sec; 781 h.h1->tp_usec = tv.tv_usec; 782 hdrlen = sizeof(*h.h1); 783 break; 784 case TPACKET_V2: 785 h.h2->tp_len = skb->len; 786 h.h2->tp_snaplen = snaplen; 787 h.h2->tp_mac = macoff; 788 h.h2->tp_net = netoff; 789 if ((po->tp_tstamp & SOF_TIMESTAMPING_SYS_HARDWARE) 790 && shhwtstamps->syststamp.tv64) 791 ts = ktime_to_timespec(shhwtstamps->syststamp); 792 else if ((po->tp_tstamp & SOF_TIMESTAMPING_RAW_HARDWARE) 793 && shhwtstamps->hwtstamp.tv64) 794 ts = ktime_to_timespec(shhwtstamps->hwtstamp); 795 else if (skb->tstamp.tv64) 796 ts = ktime_to_timespec(skb->tstamp); 797 else 798 getnstimeofday(&ts); 799 h.h2->tp_sec = ts.tv_sec; 800 h.h2->tp_nsec = ts.tv_nsec; 801 h.h2->tp_vlan_tci = vlan_tx_tag_get(skb); 802 hdrlen = sizeof(*h.h2); 803 break; 804 default: 805 BUG(); 806 } 807 808 sll = h.raw + TPACKET_ALIGN(hdrlen); 809 sll->sll_halen = dev_parse_header(skb, sll->sll_addr); 810 sll->sll_family = AF_PACKET; 811 sll->sll_hatype = dev->type; 812 sll->sll_protocol = skb->protocol; 813 sll->sll_pkttype = skb->pkt_type; 814 if (unlikely(po->origdev)) 815 sll->sll_ifindex = orig_dev->ifindex; 816 else 817 sll->sll_ifindex = dev->ifindex; 818 819 __packet_set_status(po, h.raw, status); 820 smp_mb(); 821 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1 822 { 823 u8 *start, *end; 824 825 end = (u8 *)PAGE_ALIGN((unsigned long)h.raw + macoff + snaplen); 826 for (start = h.raw; start < end; start += PAGE_SIZE) 827 flush_dcache_page(pgv_to_page(start)); 828 } 829 #endif 830 831 sk->sk_data_ready(sk, 0); 832 833 drop_n_restore: 834 if (skb_head != skb->data && skb_shared(skb)) { 835 skb->data = skb_head; 836 skb->len = skb_len; 837 } 838 drop: 839 kfree_skb(skb); 840 return 0; 841 842 ring_is_full: 843 po->stats.tp_drops++; 844 spin_unlock(&sk->sk_receive_queue.lock); 845 846 sk->sk_data_ready(sk, 0); 847 kfree_skb(copy_skb); 848 goto drop_n_restore; 849 } 850 851 static void tpacket_destruct_skb(struct sk_buff *skb) 852 { 853 struct packet_sock *po = pkt_sk(skb->sk); 854 void *ph; 855 856 BUG_ON(skb == NULL); 857 858 if (likely(po->tx_ring.pg_vec)) { 859 ph = skb_shinfo(skb)->destructor_arg; 860 BUG_ON(__packet_get_status(po, ph) != TP_STATUS_SENDING); 861 BUG_ON(atomic_read(&po->tx_ring.pending) == 0); 862 atomic_dec(&po->tx_ring.pending); 863 __packet_set_status(po, ph, TP_STATUS_AVAILABLE); 864 } 865 866 sock_wfree(skb); 867 } 868 869 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb, 870 void *frame, struct net_device *dev, int size_max, 871 __be16 proto, unsigned char *addr) 872 { 873 union { 874 struct tpacket_hdr *h1; 875 struct tpacket2_hdr *h2; 876 void *raw; 877 } ph; 878 int to_write, offset, len, tp_len, nr_frags, len_max; 879 struct socket *sock = po->sk.sk_socket; 880 struct page *page; 881 void *data; 882 int err; 883 884 ph.raw = frame; 885 886 skb->protocol = proto; 887 skb->dev = dev; 888 skb->priority = po->sk.sk_priority; 889 skb->mark = po->sk.sk_mark; 890 skb_shinfo(skb)->destructor_arg = ph.raw; 891 892 switch (po->tp_version) { 893 case TPACKET_V2: 894 tp_len = ph.h2->tp_len; 895 break; 896 default: 897 tp_len = ph.h1->tp_len; 898 break; 899 } 900 if (unlikely(tp_len > size_max)) { 901 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max); 902 return -EMSGSIZE; 903 } 904 905 skb_reserve(skb, LL_RESERVED_SPACE(dev)); 906 skb_reset_network_header(skb); 907 908 data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll); 909 to_write = tp_len; 910 911 if (sock->type == SOCK_DGRAM) { 912 err = dev_hard_header(skb, dev, ntohs(proto), addr, 913 NULL, tp_len); 914 if (unlikely(err < 0)) 915 return -EINVAL; 916 } else if (dev->hard_header_len) { 917 /* net device doesn't like empty head */ 918 if (unlikely(tp_len <= dev->hard_header_len)) { 919 pr_err("packet size is too short (%d < %d)\n", 920 tp_len, dev->hard_header_len); 921 return -EINVAL; 922 } 923 924 skb_push(skb, dev->hard_header_len); 925 err = skb_store_bits(skb, 0, data, 926 dev->hard_header_len); 927 if (unlikely(err)) 928 return err; 929 930 data += dev->hard_header_len; 931 to_write -= dev->hard_header_len; 932 } 933 934 err = -EFAULT; 935 offset = offset_in_page(data); 936 len_max = PAGE_SIZE - offset; 937 len = ((to_write > len_max) ? len_max : to_write); 938 939 skb->data_len = to_write; 940 skb->len += to_write; 941 skb->truesize += to_write; 942 atomic_add(to_write, &po->sk.sk_wmem_alloc); 943 944 while (likely(to_write)) { 945 nr_frags = skb_shinfo(skb)->nr_frags; 946 947 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) { 948 pr_err("Packet exceed the number of skb frags(%lu)\n", 949 MAX_SKB_FRAGS); 950 return -EFAULT; 951 } 952 953 page = pgv_to_page(data); 954 data += len; 955 flush_dcache_page(page); 956 get_page(page); 957 skb_fill_page_desc(skb, nr_frags, page, offset, len); 958 to_write -= len; 959 offset = 0; 960 len_max = PAGE_SIZE; 961 len = ((to_write > len_max) ? len_max : to_write); 962 } 963 964 return tp_len; 965 } 966 967 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg) 968 { 969 struct sk_buff *skb; 970 struct net_device *dev; 971 __be16 proto; 972 int ifindex, err, reserve = 0; 973 void *ph; 974 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name; 975 int tp_len, size_max; 976 unsigned char *addr; 977 int len_sum = 0; 978 int status = 0; 979 980 mutex_lock(&po->pg_vec_lock); 981 982 err = -EBUSY; 983 if (saddr == NULL) { 984 ifindex = po->ifindex; 985 proto = po->num; 986 addr = NULL; 987 } else { 988 err = -EINVAL; 989 if (msg->msg_namelen < sizeof(struct sockaddr_ll)) 990 goto out; 991 if (msg->msg_namelen < (saddr->sll_halen 992 + offsetof(struct sockaddr_ll, 993 sll_addr))) 994 goto out; 995 ifindex = saddr->sll_ifindex; 996 proto = saddr->sll_protocol; 997 addr = saddr->sll_addr; 998 } 999 1000 dev = dev_get_by_index(sock_net(&po->sk), ifindex); 1001 err = -ENXIO; 1002 if (unlikely(dev == NULL)) 1003 goto out; 1004 1005 reserve = dev->hard_header_len; 1006 1007 err = -ENETDOWN; 1008 if (unlikely(!(dev->flags & IFF_UP))) 1009 goto out_put; 1010 1011 size_max = po->tx_ring.frame_size 1012 - (po->tp_hdrlen - sizeof(struct sockaddr_ll)); 1013 1014 if (size_max > dev->mtu + reserve) 1015 size_max = dev->mtu + reserve; 1016 1017 do { 1018 ph = packet_current_frame(po, &po->tx_ring, 1019 TP_STATUS_SEND_REQUEST); 1020 1021 if (unlikely(ph == NULL)) { 1022 schedule(); 1023 continue; 1024 } 1025 1026 status = TP_STATUS_SEND_REQUEST; 1027 skb = sock_alloc_send_skb(&po->sk, 1028 LL_ALLOCATED_SPACE(dev) 1029 + sizeof(struct sockaddr_ll), 1030 0, &err); 1031 1032 if (unlikely(skb == NULL)) 1033 goto out_status; 1034 1035 tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto, 1036 addr); 1037 1038 if (unlikely(tp_len < 0)) { 1039 if (po->tp_loss) { 1040 __packet_set_status(po, ph, 1041 TP_STATUS_AVAILABLE); 1042 packet_increment_head(&po->tx_ring); 1043 kfree_skb(skb); 1044 continue; 1045 } else { 1046 status = TP_STATUS_WRONG_FORMAT; 1047 err = tp_len; 1048 goto out_status; 1049 } 1050 } 1051 1052 skb->destructor = tpacket_destruct_skb; 1053 __packet_set_status(po, ph, TP_STATUS_SENDING); 1054 atomic_inc(&po->tx_ring.pending); 1055 1056 status = TP_STATUS_SEND_REQUEST; 1057 err = dev_queue_xmit(skb); 1058 if (unlikely(err > 0)) { 1059 err = net_xmit_errno(err); 1060 if (err && __packet_get_status(po, ph) == 1061 TP_STATUS_AVAILABLE) { 1062 /* skb was destructed already */ 1063 skb = NULL; 1064 goto out_status; 1065 } 1066 /* 1067 * skb was dropped but not destructed yet; 1068 * let's treat it like congestion or err < 0 1069 */ 1070 err = 0; 1071 } 1072 packet_increment_head(&po->tx_ring); 1073 len_sum += tp_len; 1074 } while (likely((ph != NULL) || 1075 ((!(msg->msg_flags & MSG_DONTWAIT)) && 1076 (atomic_read(&po->tx_ring.pending)))) 1077 ); 1078 1079 err = len_sum; 1080 goto out_put; 1081 1082 out_status: 1083 __packet_set_status(po, ph, status); 1084 kfree_skb(skb); 1085 out_put: 1086 dev_put(dev); 1087 out: 1088 mutex_unlock(&po->pg_vec_lock); 1089 return err; 1090 } 1091 1092 static inline struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad, 1093 size_t reserve, size_t len, 1094 size_t linear, int noblock, 1095 int *err) 1096 { 1097 struct sk_buff *skb; 1098 1099 /* Under a page? Don't bother with paged skb. */ 1100 if (prepad + len < PAGE_SIZE || !linear) 1101 linear = len; 1102 1103 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock, 1104 err); 1105 if (!skb) 1106 return NULL; 1107 1108 skb_reserve(skb, reserve); 1109 skb_put(skb, linear); 1110 skb->data_len = len - linear; 1111 skb->len += len - linear; 1112 1113 return skb; 1114 } 1115 1116 static int packet_snd(struct socket *sock, 1117 struct msghdr *msg, size_t len) 1118 { 1119 struct sock *sk = sock->sk; 1120 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name; 1121 struct sk_buff *skb; 1122 struct net_device *dev; 1123 __be16 proto; 1124 unsigned char *addr; 1125 int ifindex, err, reserve = 0; 1126 struct virtio_net_hdr vnet_hdr = { 0 }; 1127 int offset = 0; 1128 int vnet_hdr_len; 1129 struct packet_sock *po = pkt_sk(sk); 1130 unsigned short gso_type = 0; 1131 1132 /* 1133 * Get and verify the address. 1134 */ 1135 1136 if (saddr == NULL) { 1137 ifindex = po->ifindex; 1138 proto = po->num; 1139 addr = NULL; 1140 } else { 1141 err = -EINVAL; 1142 if (msg->msg_namelen < sizeof(struct sockaddr_ll)) 1143 goto out; 1144 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr))) 1145 goto out; 1146 ifindex = saddr->sll_ifindex; 1147 proto = saddr->sll_protocol; 1148 addr = saddr->sll_addr; 1149 } 1150 1151 1152 dev = dev_get_by_index(sock_net(sk), ifindex); 1153 err = -ENXIO; 1154 if (dev == NULL) 1155 goto out_unlock; 1156 if (sock->type == SOCK_RAW) 1157 reserve = dev->hard_header_len; 1158 1159 err = -ENETDOWN; 1160 if (!(dev->flags & IFF_UP)) 1161 goto out_unlock; 1162 1163 if (po->has_vnet_hdr) { 1164 vnet_hdr_len = sizeof(vnet_hdr); 1165 1166 err = -EINVAL; 1167 if (len < vnet_hdr_len) 1168 goto out_unlock; 1169 1170 len -= vnet_hdr_len; 1171 1172 err = memcpy_fromiovec((void *)&vnet_hdr, msg->msg_iov, 1173 vnet_hdr_len); 1174 if (err < 0) 1175 goto out_unlock; 1176 1177 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && 1178 (vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 > 1179 vnet_hdr.hdr_len)) 1180 vnet_hdr.hdr_len = vnet_hdr.csum_start + 1181 vnet_hdr.csum_offset + 2; 1182 1183 err = -EINVAL; 1184 if (vnet_hdr.hdr_len > len) 1185 goto out_unlock; 1186 1187 if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) { 1188 switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { 1189 case VIRTIO_NET_HDR_GSO_TCPV4: 1190 gso_type = SKB_GSO_TCPV4; 1191 break; 1192 case VIRTIO_NET_HDR_GSO_TCPV6: 1193 gso_type = SKB_GSO_TCPV6; 1194 break; 1195 case VIRTIO_NET_HDR_GSO_UDP: 1196 gso_type = SKB_GSO_UDP; 1197 break; 1198 default: 1199 goto out_unlock; 1200 } 1201 1202 if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN) 1203 gso_type |= SKB_GSO_TCP_ECN; 1204 1205 if (vnet_hdr.gso_size == 0) 1206 goto out_unlock; 1207 1208 } 1209 } 1210 1211 err = -EMSGSIZE; 1212 if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN)) 1213 goto out_unlock; 1214 1215 err = -ENOBUFS; 1216 skb = packet_alloc_skb(sk, LL_ALLOCATED_SPACE(dev), 1217 LL_RESERVED_SPACE(dev), len, vnet_hdr.hdr_len, 1218 msg->msg_flags & MSG_DONTWAIT, &err); 1219 if (skb == NULL) 1220 goto out_unlock; 1221 1222 skb_set_network_header(skb, reserve); 1223 1224 err = -EINVAL; 1225 if (sock->type == SOCK_DGRAM && 1226 (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0) 1227 goto out_free; 1228 1229 /* Returns -EFAULT on error */ 1230 err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len); 1231 if (err) 1232 goto out_free; 1233 err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags); 1234 if (err < 0) 1235 goto out_free; 1236 1237 if (!gso_type && (len > dev->mtu + reserve)) { 1238 /* Earlier code assumed this would be a VLAN pkt, 1239 * double-check this now that we have the actual 1240 * packet in hand. 1241 */ 1242 struct ethhdr *ehdr; 1243 skb_reset_mac_header(skb); 1244 ehdr = eth_hdr(skb); 1245 if (ehdr->h_proto != htons(ETH_P_8021Q)) { 1246 err = -EMSGSIZE; 1247 goto out_free; 1248 } 1249 } 1250 1251 skb->protocol = proto; 1252 skb->dev = dev; 1253 skb->priority = sk->sk_priority; 1254 skb->mark = sk->sk_mark; 1255 1256 if (po->has_vnet_hdr) { 1257 if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) { 1258 if (!skb_partial_csum_set(skb, vnet_hdr.csum_start, 1259 vnet_hdr.csum_offset)) { 1260 err = -EINVAL; 1261 goto out_free; 1262 } 1263 } 1264 1265 skb_shinfo(skb)->gso_size = vnet_hdr.gso_size; 1266 skb_shinfo(skb)->gso_type = gso_type; 1267 1268 /* Header must be checked, and gso_segs computed. */ 1269 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY; 1270 skb_shinfo(skb)->gso_segs = 0; 1271 1272 len += vnet_hdr_len; 1273 } 1274 1275 /* 1276 * Now send it 1277 */ 1278 1279 err = dev_queue_xmit(skb); 1280 if (err > 0 && (err = net_xmit_errno(err)) != 0) 1281 goto out_unlock; 1282 1283 dev_put(dev); 1284 1285 return len; 1286 1287 out_free: 1288 kfree_skb(skb); 1289 out_unlock: 1290 if (dev) 1291 dev_put(dev); 1292 out: 1293 return err; 1294 } 1295 1296 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock, 1297 struct msghdr *msg, size_t len) 1298 { 1299 struct sock *sk = sock->sk; 1300 struct packet_sock *po = pkt_sk(sk); 1301 if (po->tx_ring.pg_vec) 1302 return tpacket_snd(po, msg); 1303 else 1304 return packet_snd(sock, msg, len); 1305 } 1306 1307 /* 1308 * Close a PACKET socket. This is fairly simple. We immediately go 1309 * to 'closed' state and remove our protocol entry in the device list. 1310 */ 1311 1312 static int packet_release(struct socket *sock) 1313 { 1314 struct sock *sk = sock->sk; 1315 struct packet_sock *po; 1316 struct net *net; 1317 struct tpacket_req req; 1318 1319 if (!sk) 1320 return 0; 1321 1322 net = sock_net(sk); 1323 po = pkt_sk(sk); 1324 1325 spin_lock_bh(&net->packet.sklist_lock); 1326 sk_del_node_init_rcu(sk); 1327 sock_prot_inuse_add(net, sk->sk_prot, -1); 1328 spin_unlock_bh(&net->packet.sklist_lock); 1329 1330 spin_lock(&po->bind_lock); 1331 if (po->running) { 1332 /* 1333 * Remove from protocol table 1334 */ 1335 po->running = 0; 1336 po->num = 0; 1337 __dev_remove_pack(&po->prot_hook); 1338 __sock_put(sk); 1339 } 1340 spin_unlock(&po->bind_lock); 1341 1342 packet_flush_mclist(sk); 1343 1344 memset(&req, 0, sizeof(req)); 1345 1346 if (po->rx_ring.pg_vec) 1347 packet_set_ring(sk, &req, 1, 0); 1348 1349 if (po->tx_ring.pg_vec) 1350 packet_set_ring(sk, &req, 1, 1); 1351 1352 synchronize_net(); 1353 /* 1354 * Now the socket is dead. No more input will appear. 1355 */ 1356 sock_orphan(sk); 1357 sock->sk = NULL; 1358 1359 /* Purge queues */ 1360 1361 skb_queue_purge(&sk->sk_receive_queue); 1362 sk_refcnt_debug_release(sk); 1363 1364 sock_put(sk); 1365 return 0; 1366 } 1367 1368 /* 1369 * Attach a packet hook. 1370 */ 1371 1372 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol) 1373 { 1374 struct packet_sock *po = pkt_sk(sk); 1375 /* 1376 * Detach an existing hook if present. 1377 */ 1378 1379 lock_sock(sk); 1380 1381 spin_lock(&po->bind_lock); 1382 if (po->running) { 1383 __sock_put(sk); 1384 po->running = 0; 1385 po->num = 0; 1386 spin_unlock(&po->bind_lock); 1387 dev_remove_pack(&po->prot_hook); 1388 spin_lock(&po->bind_lock); 1389 } 1390 1391 po->num = protocol; 1392 po->prot_hook.type = protocol; 1393 po->prot_hook.dev = dev; 1394 1395 po->ifindex = dev ? dev->ifindex : 0; 1396 1397 if (protocol == 0) 1398 goto out_unlock; 1399 1400 if (!dev || (dev->flags & IFF_UP)) { 1401 dev_add_pack(&po->prot_hook); 1402 sock_hold(sk); 1403 po->running = 1; 1404 } else { 1405 sk->sk_err = ENETDOWN; 1406 if (!sock_flag(sk, SOCK_DEAD)) 1407 sk->sk_error_report(sk); 1408 } 1409 1410 out_unlock: 1411 spin_unlock(&po->bind_lock); 1412 release_sock(sk); 1413 return 0; 1414 } 1415 1416 /* 1417 * Bind a packet socket to a device 1418 */ 1419 1420 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr, 1421 int addr_len) 1422 { 1423 struct sock *sk = sock->sk; 1424 char name[15]; 1425 struct net_device *dev; 1426 int err = -ENODEV; 1427 1428 /* 1429 * Check legality 1430 */ 1431 1432 if (addr_len != sizeof(struct sockaddr)) 1433 return -EINVAL; 1434 strlcpy(name, uaddr->sa_data, sizeof(name)); 1435 1436 dev = dev_get_by_name(sock_net(sk), name); 1437 if (dev) { 1438 err = packet_do_bind(sk, dev, pkt_sk(sk)->num); 1439 dev_put(dev); 1440 } 1441 return err; 1442 } 1443 1444 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) 1445 { 1446 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr; 1447 struct sock *sk = sock->sk; 1448 struct net_device *dev = NULL; 1449 int err; 1450 1451 1452 /* 1453 * Check legality 1454 */ 1455 1456 if (addr_len < sizeof(struct sockaddr_ll)) 1457 return -EINVAL; 1458 if (sll->sll_family != AF_PACKET) 1459 return -EINVAL; 1460 1461 if (sll->sll_ifindex) { 1462 err = -ENODEV; 1463 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex); 1464 if (dev == NULL) 1465 goto out; 1466 } 1467 err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num); 1468 if (dev) 1469 dev_put(dev); 1470 1471 out: 1472 return err; 1473 } 1474 1475 static struct proto packet_proto = { 1476 .name = "PACKET", 1477 .owner = THIS_MODULE, 1478 .obj_size = sizeof(struct packet_sock), 1479 }; 1480 1481 /* 1482 * Create a packet of type SOCK_PACKET. 1483 */ 1484 1485 static int packet_create(struct net *net, struct socket *sock, int protocol, 1486 int kern) 1487 { 1488 struct sock *sk; 1489 struct packet_sock *po; 1490 __be16 proto = (__force __be16)protocol; /* weird, but documented */ 1491 int err; 1492 1493 if (!capable(CAP_NET_RAW)) 1494 return -EPERM; 1495 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW && 1496 sock->type != SOCK_PACKET) 1497 return -ESOCKTNOSUPPORT; 1498 1499 sock->state = SS_UNCONNECTED; 1500 1501 err = -ENOBUFS; 1502 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto); 1503 if (sk == NULL) 1504 goto out; 1505 1506 sock->ops = &packet_ops; 1507 if (sock->type == SOCK_PACKET) 1508 sock->ops = &packet_ops_spkt; 1509 1510 sock_init_data(sock, sk); 1511 1512 po = pkt_sk(sk); 1513 sk->sk_family = PF_PACKET; 1514 po->num = proto; 1515 1516 sk->sk_destruct = packet_sock_destruct; 1517 sk_refcnt_debug_inc(sk); 1518 1519 /* 1520 * Attach a protocol block 1521 */ 1522 1523 spin_lock_init(&po->bind_lock); 1524 mutex_init(&po->pg_vec_lock); 1525 po->prot_hook.func = packet_rcv; 1526 1527 if (sock->type == SOCK_PACKET) 1528 po->prot_hook.func = packet_rcv_spkt; 1529 1530 po->prot_hook.af_packet_priv = sk; 1531 1532 if (proto) { 1533 po->prot_hook.type = proto; 1534 dev_add_pack(&po->prot_hook); 1535 sock_hold(sk); 1536 po->running = 1; 1537 } 1538 1539 spin_lock_bh(&net->packet.sklist_lock); 1540 sk_add_node_rcu(sk, &net->packet.sklist); 1541 sock_prot_inuse_add(net, &packet_proto, 1); 1542 spin_unlock_bh(&net->packet.sklist_lock); 1543 1544 return 0; 1545 out: 1546 return err; 1547 } 1548 1549 static int packet_recv_error(struct sock *sk, struct msghdr *msg, int len) 1550 { 1551 struct sock_exterr_skb *serr; 1552 struct sk_buff *skb, *skb2; 1553 int copied, err; 1554 1555 err = -EAGAIN; 1556 skb = skb_dequeue(&sk->sk_error_queue); 1557 if (skb == NULL) 1558 goto out; 1559 1560 copied = skb->len; 1561 if (copied > len) { 1562 msg->msg_flags |= MSG_TRUNC; 1563 copied = len; 1564 } 1565 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); 1566 if (err) 1567 goto out_free_skb; 1568 1569 sock_recv_timestamp(msg, sk, skb); 1570 1571 serr = SKB_EXT_ERR(skb); 1572 put_cmsg(msg, SOL_PACKET, PACKET_TX_TIMESTAMP, 1573 sizeof(serr->ee), &serr->ee); 1574 1575 msg->msg_flags |= MSG_ERRQUEUE; 1576 err = copied; 1577 1578 /* Reset and regenerate socket error */ 1579 spin_lock_bh(&sk->sk_error_queue.lock); 1580 sk->sk_err = 0; 1581 if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) { 1582 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno; 1583 spin_unlock_bh(&sk->sk_error_queue.lock); 1584 sk->sk_error_report(sk); 1585 } else 1586 spin_unlock_bh(&sk->sk_error_queue.lock); 1587 1588 out_free_skb: 1589 kfree_skb(skb); 1590 out: 1591 return err; 1592 } 1593 1594 /* 1595 * Pull a packet from our receive queue and hand it to the user. 1596 * If necessary we block. 1597 */ 1598 1599 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock, 1600 struct msghdr *msg, size_t len, int flags) 1601 { 1602 struct sock *sk = sock->sk; 1603 struct sk_buff *skb; 1604 int copied, err; 1605 struct sockaddr_ll *sll; 1606 int vnet_hdr_len = 0; 1607 1608 err = -EINVAL; 1609 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE)) 1610 goto out; 1611 1612 #if 0 1613 /* What error should we return now? EUNATTACH? */ 1614 if (pkt_sk(sk)->ifindex < 0) 1615 return -ENODEV; 1616 #endif 1617 1618 if (flags & MSG_ERRQUEUE) { 1619 err = packet_recv_error(sk, msg, len); 1620 goto out; 1621 } 1622 1623 /* 1624 * Call the generic datagram receiver. This handles all sorts 1625 * of horrible races and re-entrancy so we can forget about it 1626 * in the protocol layers. 1627 * 1628 * Now it will return ENETDOWN, if device have just gone down, 1629 * but then it will block. 1630 */ 1631 1632 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err); 1633 1634 /* 1635 * An error occurred so return it. Because skb_recv_datagram() 1636 * handles the blocking we don't see and worry about blocking 1637 * retries. 1638 */ 1639 1640 if (skb == NULL) 1641 goto out; 1642 1643 if (pkt_sk(sk)->has_vnet_hdr) { 1644 struct virtio_net_hdr vnet_hdr = { 0 }; 1645 1646 err = -EINVAL; 1647 vnet_hdr_len = sizeof(vnet_hdr); 1648 if (len < vnet_hdr_len) 1649 goto out_free; 1650 1651 len -= vnet_hdr_len; 1652 1653 if (skb_is_gso(skb)) { 1654 struct skb_shared_info *sinfo = skb_shinfo(skb); 1655 1656 /* This is a hint as to how much should be linear. */ 1657 vnet_hdr.hdr_len = skb_headlen(skb); 1658 vnet_hdr.gso_size = sinfo->gso_size; 1659 if (sinfo->gso_type & SKB_GSO_TCPV4) 1660 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4; 1661 else if (sinfo->gso_type & SKB_GSO_TCPV6) 1662 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6; 1663 else if (sinfo->gso_type & SKB_GSO_UDP) 1664 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP; 1665 else if (sinfo->gso_type & SKB_GSO_FCOE) 1666 goto out_free; 1667 else 1668 BUG(); 1669 if (sinfo->gso_type & SKB_GSO_TCP_ECN) 1670 vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN; 1671 } else 1672 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE; 1673 1674 if (skb->ip_summed == CHECKSUM_PARTIAL) { 1675 vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; 1676 vnet_hdr.csum_start = skb_checksum_start_offset(skb); 1677 vnet_hdr.csum_offset = skb->csum_offset; 1678 } /* else everything is zero */ 1679 1680 err = memcpy_toiovec(msg->msg_iov, (void *)&vnet_hdr, 1681 vnet_hdr_len); 1682 if (err < 0) 1683 goto out_free; 1684 } 1685 1686 /* 1687 * If the address length field is there to be filled in, we fill 1688 * it in now. 1689 */ 1690 1691 sll = &PACKET_SKB_CB(skb)->sa.ll; 1692 if (sock->type == SOCK_PACKET) 1693 msg->msg_namelen = sizeof(struct sockaddr_pkt); 1694 else 1695 msg->msg_namelen = sll->sll_halen + offsetof(struct sockaddr_ll, sll_addr); 1696 1697 /* 1698 * You lose any data beyond the buffer you gave. If it worries a 1699 * user program they can ask the device for its MTU anyway. 1700 */ 1701 1702 copied = skb->len; 1703 if (copied > len) { 1704 copied = len; 1705 msg->msg_flags |= MSG_TRUNC; 1706 } 1707 1708 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); 1709 if (err) 1710 goto out_free; 1711 1712 sock_recv_ts_and_drops(msg, sk, skb); 1713 1714 if (msg->msg_name) 1715 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa, 1716 msg->msg_namelen); 1717 1718 if (pkt_sk(sk)->auxdata) { 1719 struct tpacket_auxdata aux; 1720 1721 aux.tp_status = TP_STATUS_USER; 1722 if (skb->ip_summed == CHECKSUM_PARTIAL) 1723 aux.tp_status |= TP_STATUS_CSUMNOTREADY; 1724 aux.tp_len = PACKET_SKB_CB(skb)->origlen; 1725 aux.tp_snaplen = skb->len; 1726 aux.tp_mac = 0; 1727 aux.tp_net = skb_network_offset(skb); 1728 aux.tp_vlan_tci = vlan_tx_tag_get(skb); 1729 1730 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux); 1731 } 1732 1733 /* 1734 * Free or return the buffer as appropriate. Again this 1735 * hides all the races and re-entrancy issues from us. 1736 */ 1737 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied); 1738 1739 out_free: 1740 skb_free_datagram(sk, skb); 1741 out: 1742 return err; 1743 } 1744 1745 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr, 1746 int *uaddr_len, int peer) 1747 { 1748 struct net_device *dev; 1749 struct sock *sk = sock->sk; 1750 1751 if (peer) 1752 return -EOPNOTSUPP; 1753 1754 uaddr->sa_family = AF_PACKET; 1755 rcu_read_lock(); 1756 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex); 1757 if (dev) 1758 strncpy(uaddr->sa_data, dev->name, 14); 1759 else 1760 memset(uaddr->sa_data, 0, 14); 1761 rcu_read_unlock(); 1762 *uaddr_len = sizeof(*uaddr); 1763 1764 return 0; 1765 } 1766 1767 static int packet_getname(struct socket *sock, struct sockaddr *uaddr, 1768 int *uaddr_len, int peer) 1769 { 1770 struct net_device *dev; 1771 struct sock *sk = sock->sk; 1772 struct packet_sock *po = pkt_sk(sk); 1773 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr); 1774 1775 if (peer) 1776 return -EOPNOTSUPP; 1777 1778 sll->sll_family = AF_PACKET; 1779 sll->sll_ifindex = po->ifindex; 1780 sll->sll_protocol = po->num; 1781 sll->sll_pkttype = 0; 1782 rcu_read_lock(); 1783 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex); 1784 if (dev) { 1785 sll->sll_hatype = dev->type; 1786 sll->sll_halen = dev->addr_len; 1787 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len); 1788 } else { 1789 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */ 1790 sll->sll_halen = 0; 1791 } 1792 rcu_read_unlock(); 1793 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen; 1794 1795 return 0; 1796 } 1797 1798 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i, 1799 int what) 1800 { 1801 switch (i->type) { 1802 case PACKET_MR_MULTICAST: 1803 if (i->alen != dev->addr_len) 1804 return -EINVAL; 1805 if (what > 0) 1806 return dev_mc_add(dev, i->addr); 1807 else 1808 return dev_mc_del(dev, i->addr); 1809 break; 1810 case PACKET_MR_PROMISC: 1811 return dev_set_promiscuity(dev, what); 1812 break; 1813 case PACKET_MR_ALLMULTI: 1814 return dev_set_allmulti(dev, what); 1815 break; 1816 case PACKET_MR_UNICAST: 1817 if (i->alen != dev->addr_len) 1818 return -EINVAL; 1819 if (what > 0) 1820 return dev_uc_add(dev, i->addr); 1821 else 1822 return dev_uc_del(dev, i->addr); 1823 break; 1824 default: 1825 break; 1826 } 1827 return 0; 1828 } 1829 1830 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what) 1831 { 1832 for ( ; i; i = i->next) { 1833 if (i->ifindex == dev->ifindex) 1834 packet_dev_mc(dev, i, what); 1835 } 1836 } 1837 1838 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq) 1839 { 1840 struct packet_sock *po = pkt_sk(sk); 1841 struct packet_mclist *ml, *i; 1842 struct net_device *dev; 1843 int err; 1844 1845 rtnl_lock(); 1846 1847 err = -ENODEV; 1848 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex); 1849 if (!dev) 1850 goto done; 1851 1852 err = -EINVAL; 1853 if (mreq->mr_alen > dev->addr_len) 1854 goto done; 1855 1856 err = -ENOBUFS; 1857 i = kmalloc(sizeof(*i), GFP_KERNEL); 1858 if (i == NULL) 1859 goto done; 1860 1861 err = 0; 1862 for (ml = po->mclist; ml; ml = ml->next) { 1863 if (ml->ifindex == mreq->mr_ifindex && 1864 ml->type == mreq->mr_type && 1865 ml->alen == mreq->mr_alen && 1866 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) { 1867 ml->count++; 1868 /* Free the new element ... */ 1869 kfree(i); 1870 goto done; 1871 } 1872 } 1873 1874 i->type = mreq->mr_type; 1875 i->ifindex = mreq->mr_ifindex; 1876 i->alen = mreq->mr_alen; 1877 memcpy(i->addr, mreq->mr_address, i->alen); 1878 i->count = 1; 1879 i->next = po->mclist; 1880 po->mclist = i; 1881 err = packet_dev_mc(dev, i, 1); 1882 if (err) { 1883 po->mclist = i->next; 1884 kfree(i); 1885 } 1886 1887 done: 1888 rtnl_unlock(); 1889 return err; 1890 } 1891 1892 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq) 1893 { 1894 struct packet_mclist *ml, **mlp; 1895 1896 rtnl_lock(); 1897 1898 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) { 1899 if (ml->ifindex == mreq->mr_ifindex && 1900 ml->type == mreq->mr_type && 1901 ml->alen == mreq->mr_alen && 1902 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) { 1903 if (--ml->count == 0) { 1904 struct net_device *dev; 1905 *mlp = ml->next; 1906 dev = __dev_get_by_index(sock_net(sk), ml->ifindex); 1907 if (dev) 1908 packet_dev_mc(dev, ml, -1); 1909 kfree(ml); 1910 } 1911 rtnl_unlock(); 1912 return 0; 1913 } 1914 } 1915 rtnl_unlock(); 1916 return -EADDRNOTAVAIL; 1917 } 1918 1919 static void packet_flush_mclist(struct sock *sk) 1920 { 1921 struct packet_sock *po = pkt_sk(sk); 1922 struct packet_mclist *ml; 1923 1924 if (!po->mclist) 1925 return; 1926 1927 rtnl_lock(); 1928 while ((ml = po->mclist) != NULL) { 1929 struct net_device *dev; 1930 1931 po->mclist = ml->next; 1932 dev = __dev_get_by_index(sock_net(sk), ml->ifindex); 1933 if (dev != NULL) 1934 packet_dev_mc(dev, ml, -1); 1935 kfree(ml); 1936 } 1937 rtnl_unlock(); 1938 } 1939 1940 static int 1941 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen) 1942 { 1943 struct sock *sk = sock->sk; 1944 struct packet_sock *po = pkt_sk(sk); 1945 int ret; 1946 1947 if (level != SOL_PACKET) 1948 return -ENOPROTOOPT; 1949 1950 switch (optname) { 1951 case PACKET_ADD_MEMBERSHIP: 1952 case PACKET_DROP_MEMBERSHIP: 1953 { 1954 struct packet_mreq_max mreq; 1955 int len = optlen; 1956 memset(&mreq, 0, sizeof(mreq)); 1957 if (len < sizeof(struct packet_mreq)) 1958 return -EINVAL; 1959 if (len > sizeof(mreq)) 1960 len = sizeof(mreq); 1961 if (copy_from_user(&mreq, optval, len)) 1962 return -EFAULT; 1963 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address))) 1964 return -EINVAL; 1965 if (optname == PACKET_ADD_MEMBERSHIP) 1966 ret = packet_mc_add(sk, &mreq); 1967 else 1968 ret = packet_mc_drop(sk, &mreq); 1969 return ret; 1970 } 1971 1972 case PACKET_RX_RING: 1973 case PACKET_TX_RING: 1974 { 1975 struct tpacket_req req; 1976 1977 if (optlen < sizeof(req)) 1978 return -EINVAL; 1979 if (pkt_sk(sk)->has_vnet_hdr) 1980 return -EINVAL; 1981 if (copy_from_user(&req, optval, sizeof(req))) 1982 return -EFAULT; 1983 return packet_set_ring(sk, &req, 0, optname == PACKET_TX_RING); 1984 } 1985 case PACKET_COPY_THRESH: 1986 { 1987 int val; 1988 1989 if (optlen != sizeof(val)) 1990 return -EINVAL; 1991 if (copy_from_user(&val, optval, sizeof(val))) 1992 return -EFAULT; 1993 1994 pkt_sk(sk)->copy_thresh = val; 1995 return 0; 1996 } 1997 case PACKET_VERSION: 1998 { 1999 int val; 2000 2001 if (optlen != sizeof(val)) 2002 return -EINVAL; 2003 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 2004 return -EBUSY; 2005 if (copy_from_user(&val, optval, sizeof(val))) 2006 return -EFAULT; 2007 switch (val) { 2008 case TPACKET_V1: 2009 case TPACKET_V2: 2010 po->tp_version = val; 2011 return 0; 2012 default: 2013 return -EINVAL; 2014 } 2015 } 2016 case PACKET_RESERVE: 2017 { 2018 unsigned int val; 2019 2020 if (optlen != sizeof(val)) 2021 return -EINVAL; 2022 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 2023 return -EBUSY; 2024 if (copy_from_user(&val, optval, sizeof(val))) 2025 return -EFAULT; 2026 po->tp_reserve = val; 2027 return 0; 2028 } 2029 case PACKET_LOSS: 2030 { 2031 unsigned int val; 2032 2033 if (optlen != sizeof(val)) 2034 return -EINVAL; 2035 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 2036 return -EBUSY; 2037 if (copy_from_user(&val, optval, sizeof(val))) 2038 return -EFAULT; 2039 po->tp_loss = !!val; 2040 return 0; 2041 } 2042 case PACKET_AUXDATA: 2043 { 2044 int val; 2045 2046 if (optlen < sizeof(val)) 2047 return -EINVAL; 2048 if (copy_from_user(&val, optval, sizeof(val))) 2049 return -EFAULT; 2050 2051 po->auxdata = !!val; 2052 return 0; 2053 } 2054 case PACKET_ORIGDEV: 2055 { 2056 int val; 2057 2058 if (optlen < sizeof(val)) 2059 return -EINVAL; 2060 if (copy_from_user(&val, optval, sizeof(val))) 2061 return -EFAULT; 2062 2063 po->origdev = !!val; 2064 return 0; 2065 } 2066 case PACKET_VNET_HDR: 2067 { 2068 int val; 2069 2070 if (sock->type != SOCK_RAW) 2071 return -EINVAL; 2072 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 2073 return -EBUSY; 2074 if (optlen < sizeof(val)) 2075 return -EINVAL; 2076 if (copy_from_user(&val, optval, sizeof(val))) 2077 return -EFAULT; 2078 2079 po->has_vnet_hdr = !!val; 2080 return 0; 2081 } 2082 case PACKET_TIMESTAMP: 2083 { 2084 int val; 2085 2086 if (optlen != sizeof(val)) 2087 return -EINVAL; 2088 if (copy_from_user(&val, optval, sizeof(val))) 2089 return -EFAULT; 2090 2091 po->tp_tstamp = val; 2092 return 0; 2093 } 2094 default: 2095 return -ENOPROTOOPT; 2096 } 2097 } 2098 2099 static int packet_getsockopt(struct socket *sock, int level, int optname, 2100 char __user *optval, int __user *optlen) 2101 { 2102 int len; 2103 int val; 2104 struct sock *sk = sock->sk; 2105 struct packet_sock *po = pkt_sk(sk); 2106 void *data; 2107 struct tpacket_stats st; 2108 2109 if (level != SOL_PACKET) 2110 return -ENOPROTOOPT; 2111 2112 if (get_user(len, optlen)) 2113 return -EFAULT; 2114 2115 if (len < 0) 2116 return -EINVAL; 2117 2118 switch (optname) { 2119 case PACKET_STATISTICS: 2120 if (len > sizeof(struct tpacket_stats)) 2121 len = sizeof(struct tpacket_stats); 2122 spin_lock_bh(&sk->sk_receive_queue.lock); 2123 st = po->stats; 2124 memset(&po->stats, 0, sizeof(st)); 2125 spin_unlock_bh(&sk->sk_receive_queue.lock); 2126 st.tp_packets += st.tp_drops; 2127 2128 data = &st; 2129 break; 2130 case PACKET_AUXDATA: 2131 if (len > sizeof(int)) 2132 len = sizeof(int); 2133 val = po->auxdata; 2134 2135 data = &val; 2136 break; 2137 case PACKET_ORIGDEV: 2138 if (len > sizeof(int)) 2139 len = sizeof(int); 2140 val = po->origdev; 2141 2142 data = &val; 2143 break; 2144 case PACKET_VNET_HDR: 2145 if (len > sizeof(int)) 2146 len = sizeof(int); 2147 val = po->has_vnet_hdr; 2148 2149 data = &val; 2150 break; 2151 case PACKET_VERSION: 2152 if (len > sizeof(int)) 2153 len = sizeof(int); 2154 val = po->tp_version; 2155 data = &val; 2156 break; 2157 case PACKET_HDRLEN: 2158 if (len > sizeof(int)) 2159 len = sizeof(int); 2160 if (copy_from_user(&val, optval, len)) 2161 return -EFAULT; 2162 switch (val) { 2163 case TPACKET_V1: 2164 val = sizeof(struct tpacket_hdr); 2165 break; 2166 case TPACKET_V2: 2167 val = sizeof(struct tpacket2_hdr); 2168 break; 2169 default: 2170 return -EINVAL; 2171 } 2172 data = &val; 2173 break; 2174 case PACKET_RESERVE: 2175 if (len > sizeof(unsigned int)) 2176 len = sizeof(unsigned int); 2177 val = po->tp_reserve; 2178 data = &val; 2179 break; 2180 case PACKET_LOSS: 2181 if (len > sizeof(unsigned int)) 2182 len = sizeof(unsigned int); 2183 val = po->tp_loss; 2184 data = &val; 2185 break; 2186 case PACKET_TIMESTAMP: 2187 if (len > sizeof(int)) 2188 len = sizeof(int); 2189 val = po->tp_tstamp; 2190 data = &val; 2191 break; 2192 default: 2193 return -ENOPROTOOPT; 2194 } 2195 2196 if (put_user(len, optlen)) 2197 return -EFAULT; 2198 if (copy_to_user(optval, data, len)) 2199 return -EFAULT; 2200 return 0; 2201 } 2202 2203 2204 static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data) 2205 { 2206 struct sock *sk; 2207 struct hlist_node *node; 2208 struct net_device *dev = data; 2209 struct net *net = dev_net(dev); 2210 2211 rcu_read_lock(); 2212 sk_for_each_rcu(sk, node, &net->packet.sklist) { 2213 struct packet_sock *po = pkt_sk(sk); 2214 2215 switch (msg) { 2216 case NETDEV_UNREGISTER: 2217 if (po->mclist) 2218 packet_dev_mclist(dev, po->mclist, -1); 2219 /* fallthrough */ 2220 2221 case NETDEV_DOWN: 2222 if (dev->ifindex == po->ifindex) { 2223 spin_lock(&po->bind_lock); 2224 if (po->running) { 2225 __dev_remove_pack(&po->prot_hook); 2226 __sock_put(sk); 2227 po->running = 0; 2228 sk->sk_err = ENETDOWN; 2229 if (!sock_flag(sk, SOCK_DEAD)) 2230 sk->sk_error_report(sk); 2231 } 2232 if (msg == NETDEV_UNREGISTER) { 2233 po->ifindex = -1; 2234 po->prot_hook.dev = NULL; 2235 } 2236 spin_unlock(&po->bind_lock); 2237 } 2238 break; 2239 case NETDEV_UP: 2240 if (dev->ifindex == po->ifindex) { 2241 spin_lock(&po->bind_lock); 2242 if (po->num && !po->running) { 2243 dev_add_pack(&po->prot_hook); 2244 sock_hold(sk); 2245 po->running = 1; 2246 } 2247 spin_unlock(&po->bind_lock); 2248 } 2249 break; 2250 } 2251 } 2252 rcu_read_unlock(); 2253 return NOTIFY_DONE; 2254 } 2255 2256 2257 static int packet_ioctl(struct socket *sock, unsigned int cmd, 2258 unsigned long arg) 2259 { 2260 struct sock *sk = sock->sk; 2261 2262 switch (cmd) { 2263 case SIOCOUTQ: 2264 { 2265 int amount = sk_wmem_alloc_get(sk); 2266 2267 return put_user(amount, (int __user *)arg); 2268 } 2269 case SIOCINQ: 2270 { 2271 struct sk_buff *skb; 2272 int amount = 0; 2273 2274 spin_lock_bh(&sk->sk_receive_queue.lock); 2275 skb = skb_peek(&sk->sk_receive_queue); 2276 if (skb) 2277 amount = skb->len; 2278 spin_unlock_bh(&sk->sk_receive_queue.lock); 2279 return put_user(amount, (int __user *)arg); 2280 } 2281 case SIOCGSTAMP: 2282 return sock_get_timestamp(sk, (struct timeval __user *)arg); 2283 case SIOCGSTAMPNS: 2284 return sock_get_timestampns(sk, (struct timespec __user *)arg); 2285 2286 #ifdef CONFIG_INET 2287 case SIOCADDRT: 2288 case SIOCDELRT: 2289 case SIOCDARP: 2290 case SIOCGARP: 2291 case SIOCSARP: 2292 case SIOCGIFADDR: 2293 case SIOCSIFADDR: 2294 case SIOCGIFBRDADDR: 2295 case SIOCSIFBRDADDR: 2296 case SIOCGIFNETMASK: 2297 case SIOCSIFNETMASK: 2298 case SIOCGIFDSTADDR: 2299 case SIOCSIFDSTADDR: 2300 case SIOCSIFFLAGS: 2301 return inet_dgram_ops.ioctl(sock, cmd, arg); 2302 #endif 2303 2304 default: 2305 return -ENOIOCTLCMD; 2306 } 2307 return 0; 2308 } 2309 2310 static unsigned int packet_poll(struct file *file, struct socket *sock, 2311 poll_table *wait) 2312 { 2313 struct sock *sk = sock->sk; 2314 struct packet_sock *po = pkt_sk(sk); 2315 unsigned int mask = datagram_poll(file, sock, wait); 2316 2317 spin_lock_bh(&sk->sk_receive_queue.lock); 2318 if (po->rx_ring.pg_vec) { 2319 if (!packet_previous_frame(po, &po->rx_ring, TP_STATUS_KERNEL)) 2320 mask |= POLLIN | POLLRDNORM; 2321 } 2322 spin_unlock_bh(&sk->sk_receive_queue.lock); 2323 spin_lock_bh(&sk->sk_write_queue.lock); 2324 if (po->tx_ring.pg_vec) { 2325 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE)) 2326 mask |= POLLOUT | POLLWRNORM; 2327 } 2328 spin_unlock_bh(&sk->sk_write_queue.lock); 2329 return mask; 2330 } 2331 2332 2333 /* Dirty? Well, I still did not learn better way to account 2334 * for user mmaps. 2335 */ 2336 2337 static void packet_mm_open(struct vm_area_struct *vma) 2338 { 2339 struct file *file = vma->vm_file; 2340 struct socket *sock = file->private_data; 2341 struct sock *sk = sock->sk; 2342 2343 if (sk) 2344 atomic_inc(&pkt_sk(sk)->mapped); 2345 } 2346 2347 static void packet_mm_close(struct vm_area_struct *vma) 2348 { 2349 struct file *file = vma->vm_file; 2350 struct socket *sock = file->private_data; 2351 struct sock *sk = sock->sk; 2352 2353 if (sk) 2354 atomic_dec(&pkt_sk(sk)->mapped); 2355 } 2356 2357 static const struct vm_operations_struct packet_mmap_ops = { 2358 .open = packet_mm_open, 2359 .close = packet_mm_close, 2360 }; 2361 2362 static void free_pg_vec(struct pgv *pg_vec, unsigned int order, 2363 unsigned int len) 2364 { 2365 int i; 2366 2367 for (i = 0; i < len; i++) { 2368 if (likely(pg_vec[i].buffer)) { 2369 if (is_vmalloc_addr(pg_vec[i].buffer)) 2370 vfree(pg_vec[i].buffer); 2371 else 2372 free_pages((unsigned long)pg_vec[i].buffer, 2373 order); 2374 pg_vec[i].buffer = NULL; 2375 } 2376 } 2377 kfree(pg_vec); 2378 } 2379 2380 static inline char *alloc_one_pg_vec_page(unsigned long order) 2381 { 2382 char *buffer = NULL; 2383 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP | 2384 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY; 2385 2386 buffer = (char *) __get_free_pages(gfp_flags, order); 2387 2388 if (buffer) 2389 return buffer; 2390 2391 /* 2392 * __get_free_pages failed, fall back to vmalloc 2393 */ 2394 buffer = vzalloc((1 << order) * PAGE_SIZE); 2395 2396 if (buffer) 2397 return buffer; 2398 2399 /* 2400 * vmalloc failed, lets dig into swap here 2401 */ 2402 gfp_flags &= ~__GFP_NORETRY; 2403 buffer = (char *)__get_free_pages(gfp_flags, order); 2404 if (buffer) 2405 return buffer; 2406 2407 /* 2408 * complete and utter failure 2409 */ 2410 return NULL; 2411 } 2412 2413 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order) 2414 { 2415 unsigned int block_nr = req->tp_block_nr; 2416 struct pgv *pg_vec; 2417 int i; 2418 2419 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL); 2420 if (unlikely(!pg_vec)) 2421 goto out; 2422 2423 for (i = 0; i < block_nr; i++) { 2424 pg_vec[i].buffer = alloc_one_pg_vec_page(order); 2425 if (unlikely(!pg_vec[i].buffer)) 2426 goto out_free_pgvec; 2427 } 2428 2429 out: 2430 return pg_vec; 2431 2432 out_free_pgvec: 2433 free_pg_vec(pg_vec, order, block_nr); 2434 pg_vec = NULL; 2435 goto out; 2436 } 2437 2438 static int packet_set_ring(struct sock *sk, struct tpacket_req *req, 2439 int closing, int tx_ring) 2440 { 2441 struct pgv *pg_vec = NULL; 2442 struct packet_sock *po = pkt_sk(sk); 2443 int was_running, order = 0; 2444 struct packet_ring_buffer *rb; 2445 struct sk_buff_head *rb_queue; 2446 __be16 num; 2447 int err; 2448 2449 rb = tx_ring ? &po->tx_ring : &po->rx_ring; 2450 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue; 2451 2452 err = -EBUSY; 2453 if (!closing) { 2454 if (atomic_read(&po->mapped)) 2455 goto out; 2456 if (atomic_read(&rb->pending)) 2457 goto out; 2458 } 2459 2460 if (req->tp_block_nr) { 2461 /* Sanity tests and some calculations */ 2462 err = -EBUSY; 2463 if (unlikely(rb->pg_vec)) 2464 goto out; 2465 2466 switch (po->tp_version) { 2467 case TPACKET_V1: 2468 po->tp_hdrlen = TPACKET_HDRLEN; 2469 break; 2470 case TPACKET_V2: 2471 po->tp_hdrlen = TPACKET2_HDRLEN; 2472 break; 2473 } 2474 2475 err = -EINVAL; 2476 if (unlikely((int)req->tp_block_size <= 0)) 2477 goto out; 2478 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1))) 2479 goto out; 2480 if (unlikely(req->tp_frame_size < po->tp_hdrlen + 2481 po->tp_reserve)) 2482 goto out; 2483 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1))) 2484 goto out; 2485 2486 rb->frames_per_block = req->tp_block_size/req->tp_frame_size; 2487 if (unlikely(rb->frames_per_block <= 0)) 2488 goto out; 2489 if (unlikely((rb->frames_per_block * req->tp_block_nr) != 2490 req->tp_frame_nr)) 2491 goto out; 2492 2493 err = -ENOMEM; 2494 order = get_order(req->tp_block_size); 2495 pg_vec = alloc_pg_vec(req, order); 2496 if (unlikely(!pg_vec)) 2497 goto out; 2498 } 2499 /* Done */ 2500 else { 2501 err = -EINVAL; 2502 if (unlikely(req->tp_frame_nr)) 2503 goto out; 2504 } 2505 2506 lock_sock(sk); 2507 2508 /* Detach socket from network */ 2509 spin_lock(&po->bind_lock); 2510 was_running = po->running; 2511 num = po->num; 2512 if (was_running) { 2513 __dev_remove_pack(&po->prot_hook); 2514 po->num = 0; 2515 po->running = 0; 2516 __sock_put(sk); 2517 } 2518 spin_unlock(&po->bind_lock); 2519 2520 synchronize_net(); 2521 2522 err = -EBUSY; 2523 mutex_lock(&po->pg_vec_lock); 2524 if (closing || atomic_read(&po->mapped) == 0) { 2525 err = 0; 2526 spin_lock_bh(&rb_queue->lock); 2527 swap(rb->pg_vec, pg_vec); 2528 rb->frame_max = (req->tp_frame_nr - 1); 2529 rb->head = 0; 2530 rb->frame_size = req->tp_frame_size; 2531 spin_unlock_bh(&rb_queue->lock); 2532 2533 swap(rb->pg_vec_order, order); 2534 swap(rb->pg_vec_len, req->tp_block_nr); 2535 2536 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE; 2537 po->prot_hook.func = (po->rx_ring.pg_vec) ? 2538 tpacket_rcv : packet_rcv; 2539 skb_queue_purge(rb_queue); 2540 if (atomic_read(&po->mapped)) 2541 pr_err("packet_mmap: vma is busy: %d\n", 2542 atomic_read(&po->mapped)); 2543 } 2544 mutex_unlock(&po->pg_vec_lock); 2545 2546 spin_lock(&po->bind_lock); 2547 if (was_running && !po->running) { 2548 sock_hold(sk); 2549 po->running = 1; 2550 po->num = num; 2551 dev_add_pack(&po->prot_hook); 2552 } 2553 spin_unlock(&po->bind_lock); 2554 2555 release_sock(sk); 2556 2557 if (pg_vec) 2558 free_pg_vec(pg_vec, order, req->tp_block_nr); 2559 out: 2560 return err; 2561 } 2562 2563 static int packet_mmap(struct file *file, struct socket *sock, 2564 struct vm_area_struct *vma) 2565 { 2566 struct sock *sk = sock->sk; 2567 struct packet_sock *po = pkt_sk(sk); 2568 unsigned long size, expected_size; 2569 struct packet_ring_buffer *rb; 2570 unsigned long start; 2571 int err = -EINVAL; 2572 int i; 2573 2574 if (vma->vm_pgoff) 2575 return -EINVAL; 2576 2577 mutex_lock(&po->pg_vec_lock); 2578 2579 expected_size = 0; 2580 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) { 2581 if (rb->pg_vec) { 2582 expected_size += rb->pg_vec_len 2583 * rb->pg_vec_pages 2584 * PAGE_SIZE; 2585 } 2586 } 2587 2588 if (expected_size == 0) 2589 goto out; 2590 2591 size = vma->vm_end - vma->vm_start; 2592 if (size != expected_size) 2593 goto out; 2594 2595 start = vma->vm_start; 2596 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) { 2597 if (rb->pg_vec == NULL) 2598 continue; 2599 2600 for (i = 0; i < rb->pg_vec_len; i++) { 2601 struct page *page; 2602 void *kaddr = rb->pg_vec[i].buffer; 2603 int pg_num; 2604 2605 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) { 2606 page = pgv_to_page(kaddr); 2607 err = vm_insert_page(vma, start, page); 2608 if (unlikely(err)) 2609 goto out; 2610 start += PAGE_SIZE; 2611 kaddr += PAGE_SIZE; 2612 } 2613 } 2614 } 2615 2616 atomic_inc(&po->mapped); 2617 vma->vm_ops = &packet_mmap_ops; 2618 err = 0; 2619 2620 out: 2621 mutex_unlock(&po->pg_vec_lock); 2622 return err; 2623 } 2624 2625 static const struct proto_ops packet_ops_spkt = { 2626 .family = PF_PACKET, 2627 .owner = THIS_MODULE, 2628 .release = packet_release, 2629 .bind = packet_bind_spkt, 2630 .connect = sock_no_connect, 2631 .socketpair = sock_no_socketpair, 2632 .accept = sock_no_accept, 2633 .getname = packet_getname_spkt, 2634 .poll = datagram_poll, 2635 .ioctl = packet_ioctl, 2636 .listen = sock_no_listen, 2637 .shutdown = sock_no_shutdown, 2638 .setsockopt = sock_no_setsockopt, 2639 .getsockopt = sock_no_getsockopt, 2640 .sendmsg = packet_sendmsg_spkt, 2641 .recvmsg = packet_recvmsg, 2642 .mmap = sock_no_mmap, 2643 .sendpage = sock_no_sendpage, 2644 }; 2645 2646 static const struct proto_ops packet_ops = { 2647 .family = PF_PACKET, 2648 .owner = THIS_MODULE, 2649 .release = packet_release, 2650 .bind = packet_bind, 2651 .connect = sock_no_connect, 2652 .socketpair = sock_no_socketpair, 2653 .accept = sock_no_accept, 2654 .getname = packet_getname, 2655 .poll = packet_poll, 2656 .ioctl = packet_ioctl, 2657 .listen = sock_no_listen, 2658 .shutdown = sock_no_shutdown, 2659 .setsockopt = packet_setsockopt, 2660 .getsockopt = packet_getsockopt, 2661 .sendmsg = packet_sendmsg, 2662 .recvmsg = packet_recvmsg, 2663 .mmap = packet_mmap, 2664 .sendpage = sock_no_sendpage, 2665 }; 2666 2667 static const struct net_proto_family packet_family_ops = { 2668 .family = PF_PACKET, 2669 .create = packet_create, 2670 .owner = THIS_MODULE, 2671 }; 2672 2673 static struct notifier_block packet_netdev_notifier = { 2674 .notifier_call = packet_notifier, 2675 }; 2676 2677 #ifdef CONFIG_PROC_FS 2678 2679 static void *packet_seq_start(struct seq_file *seq, loff_t *pos) 2680 __acquires(RCU) 2681 { 2682 struct net *net = seq_file_net(seq); 2683 2684 rcu_read_lock(); 2685 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos); 2686 } 2687 2688 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2689 { 2690 struct net *net = seq_file_net(seq); 2691 return seq_hlist_next_rcu(v, &net->packet.sklist, pos); 2692 } 2693 2694 static void packet_seq_stop(struct seq_file *seq, void *v) 2695 __releases(RCU) 2696 { 2697 rcu_read_unlock(); 2698 } 2699 2700 static int packet_seq_show(struct seq_file *seq, void *v) 2701 { 2702 if (v == SEQ_START_TOKEN) 2703 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n"); 2704 else { 2705 struct sock *s = sk_entry(v); 2706 const struct packet_sock *po = pkt_sk(s); 2707 2708 seq_printf(seq, 2709 "%p %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n", 2710 s, 2711 atomic_read(&s->sk_refcnt), 2712 s->sk_type, 2713 ntohs(po->num), 2714 po->ifindex, 2715 po->running, 2716 atomic_read(&s->sk_rmem_alloc), 2717 sock_i_uid(s), 2718 sock_i_ino(s)); 2719 } 2720 2721 return 0; 2722 } 2723 2724 static const struct seq_operations packet_seq_ops = { 2725 .start = packet_seq_start, 2726 .next = packet_seq_next, 2727 .stop = packet_seq_stop, 2728 .show = packet_seq_show, 2729 }; 2730 2731 static int packet_seq_open(struct inode *inode, struct file *file) 2732 { 2733 return seq_open_net(inode, file, &packet_seq_ops, 2734 sizeof(struct seq_net_private)); 2735 } 2736 2737 static const struct file_operations packet_seq_fops = { 2738 .owner = THIS_MODULE, 2739 .open = packet_seq_open, 2740 .read = seq_read, 2741 .llseek = seq_lseek, 2742 .release = seq_release_net, 2743 }; 2744 2745 #endif 2746 2747 static int __net_init packet_net_init(struct net *net) 2748 { 2749 spin_lock_init(&net->packet.sklist_lock); 2750 INIT_HLIST_HEAD(&net->packet.sklist); 2751 2752 if (!proc_net_fops_create(net, "packet", 0, &packet_seq_fops)) 2753 return -ENOMEM; 2754 2755 return 0; 2756 } 2757 2758 static void __net_exit packet_net_exit(struct net *net) 2759 { 2760 proc_net_remove(net, "packet"); 2761 } 2762 2763 static struct pernet_operations packet_net_ops = { 2764 .init = packet_net_init, 2765 .exit = packet_net_exit, 2766 }; 2767 2768 2769 static void __exit packet_exit(void) 2770 { 2771 unregister_netdevice_notifier(&packet_netdev_notifier); 2772 unregister_pernet_subsys(&packet_net_ops); 2773 sock_unregister(PF_PACKET); 2774 proto_unregister(&packet_proto); 2775 } 2776 2777 static int __init packet_init(void) 2778 { 2779 int rc = proto_register(&packet_proto, 0); 2780 2781 if (rc != 0) 2782 goto out; 2783 2784 sock_register(&packet_family_ops); 2785 register_pernet_subsys(&packet_net_ops); 2786 register_netdevice_notifier(&packet_netdev_notifier); 2787 out: 2788 return rc; 2789 } 2790 2791 module_init(packet_init); 2792 module_exit(packet_exit); 2793 MODULE_LICENSE("GPL"); 2794 MODULE_ALIAS_NETPROTO(PF_PACKET); 2795