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 if (vlan_tx_tag_present(skb)) { 802 h.h2->tp_vlan_tci = vlan_tx_tag_get(skb); 803 status |= TP_STATUS_VLAN_VALID; 804 } else { 805 h.h2->tp_vlan_tci = 0; 806 } 807 h.h2->tp_padding = 0; 808 hdrlen = sizeof(*h.h2); 809 break; 810 default: 811 BUG(); 812 } 813 814 sll = h.raw + TPACKET_ALIGN(hdrlen); 815 sll->sll_halen = dev_parse_header(skb, sll->sll_addr); 816 sll->sll_family = AF_PACKET; 817 sll->sll_hatype = dev->type; 818 sll->sll_protocol = skb->protocol; 819 sll->sll_pkttype = skb->pkt_type; 820 if (unlikely(po->origdev)) 821 sll->sll_ifindex = orig_dev->ifindex; 822 else 823 sll->sll_ifindex = dev->ifindex; 824 825 __packet_set_status(po, h.raw, status); 826 smp_mb(); 827 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1 828 { 829 u8 *start, *end; 830 831 end = (u8 *)PAGE_ALIGN((unsigned long)h.raw + macoff + snaplen); 832 for (start = h.raw; start < end; start += PAGE_SIZE) 833 flush_dcache_page(pgv_to_page(start)); 834 } 835 #endif 836 837 sk->sk_data_ready(sk, 0); 838 839 drop_n_restore: 840 if (skb_head != skb->data && skb_shared(skb)) { 841 skb->data = skb_head; 842 skb->len = skb_len; 843 } 844 drop: 845 kfree_skb(skb); 846 return 0; 847 848 ring_is_full: 849 po->stats.tp_drops++; 850 spin_unlock(&sk->sk_receive_queue.lock); 851 852 sk->sk_data_ready(sk, 0); 853 kfree_skb(copy_skb); 854 goto drop_n_restore; 855 } 856 857 static void tpacket_destruct_skb(struct sk_buff *skb) 858 { 859 struct packet_sock *po = pkt_sk(skb->sk); 860 void *ph; 861 862 BUG_ON(skb == NULL); 863 864 if (likely(po->tx_ring.pg_vec)) { 865 ph = skb_shinfo(skb)->destructor_arg; 866 BUG_ON(__packet_get_status(po, ph) != TP_STATUS_SENDING); 867 BUG_ON(atomic_read(&po->tx_ring.pending) == 0); 868 atomic_dec(&po->tx_ring.pending); 869 __packet_set_status(po, ph, TP_STATUS_AVAILABLE); 870 } 871 872 sock_wfree(skb); 873 } 874 875 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb, 876 void *frame, struct net_device *dev, int size_max, 877 __be16 proto, unsigned char *addr) 878 { 879 union { 880 struct tpacket_hdr *h1; 881 struct tpacket2_hdr *h2; 882 void *raw; 883 } ph; 884 int to_write, offset, len, tp_len, nr_frags, len_max; 885 struct socket *sock = po->sk.sk_socket; 886 struct page *page; 887 void *data; 888 int err; 889 890 ph.raw = frame; 891 892 skb->protocol = proto; 893 skb->dev = dev; 894 skb->priority = po->sk.sk_priority; 895 skb->mark = po->sk.sk_mark; 896 skb_shinfo(skb)->destructor_arg = ph.raw; 897 898 switch (po->tp_version) { 899 case TPACKET_V2: 900 tp_len = ph.h2->tp_len; 901 break; 902 default: 903 tp_len = ph.h1->tp_len; 904 break; 905 } 906 if (unlikely(tp_len > size_max)) { 907 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max); 908 return -EMSGSIZE; 909 } 910 911 skb_reserve(skb, LL_RESERVED_SPACE(dev)); 912 skb_reset_network_header(skb); 913 914 data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll); 915 to_write = tp_len; 916 917 if (sock->type == SOCK_DGRAM) { 918 err = dev_hard_header(skb, dev, ntohs(proto), addr, 919 NULL, tp_len); 920 if (unlikely(err < 0)) 921 return -EINVAL; 922 } else if (dev->hard_header_len) { 923 /* net device doesn't like empty head */ 924 if (unlikely(tp_len <= dev->hard_header_len)) { 925 pr_err("packet size is too short (%d < %d)\n", 926 tp_len, dev->hard_header_len); 927 return -EINVAL; 928 } 929 930 skb_push(skb, dev->hard_header_len); 931 err = skb_store_bits(skb, 0, data, 932 dev->hard_header_len); 933 if (unlikely(err)) 934 return err; 935 936 data += dev->hard_header_len; 937 to_write -= dev->hard_header_len; 938 } 939 940 err = -EFAULT; 941 offset = offset_in_page(data); 942 len_max = PAGE_SIZE - offset; 943 len = ((to_write > len_max) ? len_max : to_write); 944 945 skb->data_len = to_write; 946 skb->len += to_write; 947 skb->truesize += to_write; 948 atomic_add(to_write, &po->sk.sk_wmem_alloc); 949 950 while (likely(to_write)) { 951 nr_frags = skb_shinfo(skb)->nr_frags; 952 953 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) { 954 pr_err("Packet exceed the number of skb frags(%lu)\n", 955 MAX_SKB_FRAGS); 956 return -EFAULT; 957 } 958 959 page = pgv_to_page(data); 960 data += len; 961 flush_dcache_page(page); 962 get_page(page); 963 skb_fill_page_desc(skb, nr_frags, page, offset, len); 964 to_write -= len; 965 offset = 0; 966 len_max = PAGE_SIZE; 967 len = ((to_write > len_max) ? len_max : to_write); 968 } 969 970 return tp_len; 971 } 972 973 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg) 974 { 975 struct sk_buff *skb; 976 struct net_device *dev; 977 __be16 proto; 978 int ifindex, err, reserve = 0; 979 void *ph; 980 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name; 981 int tp_len, size_max; 982 unsigned char *addr; 983 int len_sum = 0; 984 int status = 0; 985 986 mutex_lock(&po->pg_vec_lock); 987 988 err = -EBUSY; 989 if (saddr == NULL) { 990 ifindex = po->ifindex; 991 proto = po->num; 992 addr = NULL; 993 } else { 994 err = -EINVAL; 995 if (msg->msg_namelen < sizeof(struct sockaddr_ll)) 996 goto out; 997 if (msg->msg_namelen < (saddr->sll_halen 998 + offsetof(struct sockaddr_ll, 999 sll_addr))) 1000 goto out; 1001 ifindex = saddr->sll_ifindex; 1002 proto = saddr->sll_protocol; 1003 addr = saddr->sll_addr; 1004 } 1005 1006 dev = dev_get_by_index(sock_net(&po->sk), ifindex); 1007 err = -ENXIO; 1008 if (unlikely(dev == NULL)) 1009 goto out; 1010 1011 reserve = dev->hard_header_len; 1012 1013 err = -ENETDOWN; 1014 if (unlikely(!(dev->flags & IFF_UP))) 1015 goto out_put; 1016 1017 size_max = po->tx_ring.frame_size 1018 - (po->tp_hdrlen - sizeof(struct sockaddr_ll)); 1019 1020 if (size_max > dev->mtu + reserve) 1021 size_max = dev->mtu + reserve; 1022 1023 do { 1024 ph = packet_current_frame(po, &po->tx_ring, 1025 TP_STATUS_SEND_REQUEST); 1026 1027 if (unlikely(ph == NULL)) { 1028 schedule(); 1029 continue; 1030 } 1031 1032 status = TP_STATUS_SEND_REQUEST; 1033 skb = sock_alloc_send_skb(&po->sk, 1034 LL_ALLOCATED_SPACE(dev) 1035 + sizeof(struct sockaddr_ll), 1036 0, &err); 1037 1038 if (unlikely(skb == NULL)) 1039 goto out_status; 1040 1041 tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto, 1042 addr); 1043 1044 if (unlikely(tp_len < 0)) { 1045 if (po->tp_loss) { 1046 __packet_set_status(po, ph, 1047 TP_STATUS_AVAILABLE); 1048 packet_increment_head(&po->tx_ring); 1049 kfree_skb(skb); 1050 continue; 1051 } else { 1052 status = TP_STATUS_WRONG_FORMAT; 1053 err = tp_len; 1054 goto out_status; 1055 } 1056 } 1057 1058 skb->destructor = tpacket_destruct_skb; 1059 __packet_set_status(po, ph, TP_STATUS_SENDING); 1060 atomic_inc(&po->tx_ring.pending); 1061 1062 status = TP_STATUS_SEND_REQUEST; 1063 err = dev_queue_xmit(skb); 1064 if (unlikely(err > 0)) { 1065 err = net_xmit_errno(err); 1066 if (err && __packet_get_status(po, ph) == 1067 TP_STATUS_AVAILABLE) { 1068 /* skb was destructed already */ 1069 skb = NULL; 1070 goto out_status; 1071 } 1072 /* 1073 * skb was dropped but not destructed yet; 1074 * let's treat it like congestion or err < 0 1075 */ 1076 err = 0; 1077 } 1078 packet_increment_head(&po->tx_ring); 1079 len_sum += tp_len; 1080 } while (likely((ph != NULL) || 1081 ((!(msg->msg_flags & MSG_DONTWAIT)) && 1082 (atomic_read(&po->tx_ring.pending)))) 1083 ); 1084 1085 err = len_sum; 1086 goto out_put; 1087 1088 out_status: 1089 __packet_set_status(po, ph, status); 1090 kfree_skb(skb); 1091 out_put: 1092 dev_put(dev); 1093 out: 1094 mutex_unlock(&po->pg_vec_lock); 1095 return err; 1096 } 1097 1098 static inline struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad, 1099 size_t reserve, size_t len, 1100 size_t linear, int noblock, 1101 int *err) 1102 { 1103 struct sk_buff *skb; 1104 1105 /* Under a page? Don't bother with paged skb. */ 1106 if (prepad + len < PAGE_SIZE || !linear) 1107 linear = len; 1108 1109 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock, 1110 err); 1111 if (!skb) 1112 return NULL; 1113 1114 skb_reserve(skb, reserve); 1115 skb_put(skb, linear); 1116 skb->data_len = len - linear; 1117 skb->len += len - linear; 1118 1119 return skb; 1120 } 1121 1122 static int packet_snd(struct socket *sock, 1123 struct msghdr *msg, size_t len) 1124 { 1125 struct sock *sk = sock->sk; 1126 struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name; 1127 struct sk_buff *skb; 1128 struct net_device *dev; 1129 __be16 proto; 1130 unsigned char *addr; 1131 int ifindex, err, reserve = 0; 1132 struct virtio_net_hdr vnet_hdr = { 0 }; 1133 int offset = 0; 1134 int vnet_hdr_len; 1135 struct packet_sock *po = pkt_sk(sk); 1136 unsigned short gso_type = 0; 1137 1138 /* 1139 * Get and verify the address. 1140 */ 1141 1142 if (saddr == NULL) { 1143 ifindex = po->ifindex; 1144 proto = po->num; 1145 addr = NULL; 1146 } else { 1147 err = -EINVAL; 1148 if (msg->msg_namelen < sizeof(struct sockaddr_ll)) 1149 goto out; 1150 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr))) 1151 goto out; 1152 ifindex = saddr->sll_ifindex; 1153 proto = saddr->sll_protocol; 1154 addr = saddr->sll_addr; 1155 } 1156 1157 1158 dev = dev_get_by_index(sock_net(sk), ifindex); 1159 err = -ENXIO; 1160 if (dev == NULL) 1161 goto out_unlock; 1162 if (sock->type == SOCK_RAW) 1163 reserve = dev->hard_header_len; 1164 1165 err = -ENETDOWN; 1166 if (!(dev->flags & IFF_UP)) 1167 goto out_unlock; 1168 1169 if (po->has_vnet_hdr) { 1170 vnet_hdr_len = sizeof(vnet_hdr); 1171 1172 err = -EINVAL; 1173 if (len < vnet_hdr_len) 1174 goto out_unlock; 1175 1176 len -= vnet_hdr_len; 1177 1178 err = memcpy_fromiovec((void *)&vnet_hdr, msg->msg_iov, 1179 vnet_hdr_len); 1180 if (err < 0) 1181 goto out_unlock; 1182 1183 if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && 1184 (vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 > 1185 vnet_hdr.hdr_len)) 1186 vnet_hdr.hdr_len = vnet_hdr.csum_start + 1187 vnet_hdr.csum_offset + 2; 1188 1189 err = -EINVAL; 1190 if (vnet_hdr.hdr_len > len) 1191 goto out_unlock; 1192 1193 if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) { 1194 switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { 1195 case VIRTIO_NET_HDR_GSO_TCPV4: 1196 gso_type = SKB_GSO_TCPV4; 1197 break; 1198 case VIRTIO_NET_HDR_GSO_TCPV6: 1199 gso_type = SKB_GSO_TCPV6; 1200 break; 1201 case VIRTIO_NET_HDR_GSO_UDP: 1202 gso_type = SKB_GSO_UDP; 1203 break; 1204 default: 1205 goto out_unlock; 1206 } 1207 1208 if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN) 1209 gso_type |= SKB_GSO_TCP_ECN; 1210 1211 if (vnet_hdr.gso_size == 0) 1212 goto out_unlock; 1213 1214 } 1215 } 1216 1217 err = -EMSGSIZE; 1218 if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN)) 1219 goto out_unlock; 1220 1221 err = -ENOBUFS; 1222 skb = packet_alloc_skb(sk, LL_ALLOCATED_SPACE(dev), 1223 LL_RESERVED_SPACE(dev), len, vnet_hdr.hdr_len, 1224 msg->msg_flags & MSG_DONTWAIT, &err); 1225 if (skb == NULL) 1226 goto out_unlock; 1227 1228 skb_set_network_header(skb, reserve); 1229 1230 err = -EINVAL; 1231 if (sock->type == SOCK_DGRAM && 1232 (offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len)) < 0) 1233 goto out_free; 1234 1235 /* Returns -EFAULT on error */ 1236 err = skb_copy_datagram_from_iovec(skb, offset, msg->msg_iov, 0, len); 1237 if (err) 1238 goto out_free; 1239 err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags); 1240 if (err < 0) 1241 goto out_free; 1242 1243 if (!gso_type && (len > dev->mtu + reserve)) { 1244 /* Earlier code assumed this would be a VLAN pkt, 1245 * double-check this now that we have the actual 1246 * packet in hand. 1247 */ 1248 struct ethhdr *ehdr; 1249 skb_reset_mac_header(skb); 1250 ehdr = eth_hdr(skb); 1251 if (ehdr->h_proto != htons(ETH_P_8021Q)) { 1252 err = -EMSGSIZE; 1253 goto out_free; 1254 } 1255 } 1256 1257 skb->protocol = proto; 1258 skb->dev = dev; 1259 skb->priority = sk->sk_priority; 1260 skb->mark = sk->sk_mark; 1261 1262 if (po->has_vnet_hdr) { 1263 if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) { 1264 if (!skb_partial_csum_set(skb, vnet_hdr.csum_start, 1265 vnet_hdr.csum_offset)) { 1266 err = -EINVAL; 1267 goto out_free; 1268 } 1269 } 1270 1271 skb_shinfo(skb)->gso_size = vnet_hdr.gso_size; 1272 skb_shinfo(skb)->gso_type = gso_type; 1273 1274 /* Header must be checked, and gso_segs computed. */ 1275 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY; 1276 skb_shinfo(skb)->gso_segs = 0; 1277 1278 len += vnet_hdr_len; 1279 } 1280 1281 /* 1282 * Now send it 1283 */ 1284 1285 err = dev_queue_xmit(skb); 1286 if (err > 0 && (err = net_xmit_errno(err)) != 0) 1287 goto out_unlock; 1288 1289 dev_put(dev); 1290 1291 return len; 1292 1293 out_free: 1294 kfree_skb(skb); 1295 out_unlock: 1296 if (dev) 1297 dev_put(dev); 1298 out: 1299 return err; 1300 } 1301 1302 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock, 1303 struct msghdr *msg, size_t len) 1304 { 1305 struct sock *sk = sock->sk; 1306 struct packet_sock *po = pkt_sk(sk); 1307 if (po->tx_ring.pg_vec) 1308 return tpacket_snd(po, msg); 1309 else 1310 return packet_snd(sock, msg, len); 1311 } 1312 1313 /* 1314 * Close a PACKET socket. This is fairly simple. We immediately go 1315 * to 'closed' state and remove our protocol entry in the device list. 1316 */ 1317 1318 static int packet_release(struct socket *sock) 1319 { 1320 struct sock *sk = sock->sk; 1321 struct packet_sock *po; 1322 struct net *net; 1323 struct tpacket_req req; 1324 1325 if (!sk) 1326 return 0; 1327 1328 net = sock_net(sk); 1329 po = pkt_sk(sk); 1330 1331 spin_lock_bh(&net->packet.sklist_lock); 1332 sk_del_node_init_rcu(sk); 1333 sock_prot_inuse_add(net, sk->sk_prot, -1); 1334 spin_unlock_bh(&net->packet.sklist_lock); 1335 1336 spin_lock(&po->bind_lock); 1337 if (po->running) { 1338 /* 1339 * Remove from protocol table 1340 */ 1341 po->running = 0; 1342 po->num = 0; 1343 __dev_remove_pack(&po->prot_hook); 1344 __sock_put(sk); 1345 } 1346 spin_unlock(&po->bind_lock); 1347 1348 packet_flush_mclist(sk); 1349 1350 memset(&req, 0, sizeof(req)); 1351 1352 if (po->rx_ring.pg_vec) 1353 packet_set_ring(sk, &req, 1, 0); 1354 1355 if (po->tx_ring.pg_vec) 1356 packet_set_ring(sk, &req, 1, 1); 1357 1358 synchronize_net(); 1359 /* 1360 * Now the socket is dead. No more input will appear. 1361 */ 1362 sock_orphan(sk); 1363 sock->sk = NULL; 1364 1365 /* Purge queues */ 1366 1367 skb_queue_purge(&sk->sk_receive_queue); 1368 sk_refcnt_debug_release(sk); 1369 1370 sock_put(sk); 1371 return 0; 1372 } 1373 1374 /* 1375 * Attach a packet hook. 1376 */ 1377 1378 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol) 1379 { 1380 struct packet_sock *po = pkt_sk(sk); 1381 /* 1382 * Detach an existing hook if present. 1383 */ 1384 1385 lock_sock(sk); 1386 1387 spin_lock(&po->bind_lock); 1388 if (po->running) { 1389 __sock_put(sk); 1390 po->running = 0; 1391 po->num = 0; 1392 spin_unlock(&po->bind_lock); 1393 dev_remove_pack(&po->prot_hook); 1394 spin_lock(&po->bind_lock); 1395 } 1396 1397 po->num = protocol; 1398 po->prot_hook.type = protocol; 1399 po->prot_hook.dev = dev; 1400 1401 po->ifindex = dev ? dev->ifindex : 0; 1402 1403 if (protocol == 0) 1404 goto out_unlock; 1405 1406 if (!dev || (dev->flags & IFF_UP)) { 1407 dev_add_pack(&po->prot_hook); 1408 sock_hold(sk); 1409 po->running = 1; 1410 } else { 1411 sk->sk_err = ENETDOWN; 1412 if (!sock_flag(sk, SOCK_DEAD)) 1413 sk->sk_error_report(sk); 1414 } 1415 1416 out_unlock: 1417 spin_unlock(&po->bind_lock); 1418 release_sock(sk); 1419 return 0; 1420 } 1421 1422 /* 1423 * Bind a packet socket to a device 1424 */ 1425 1426 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr, 1427 int addr_len) 1428 { 1429 struct sock *sk = sock->sk; 1430 char name[15]; 1431 struct net_device *dev; 1432 int err = -ENODEV; 1433 1434 /* 1435 * Check legality 1436 */ 1437 1438 if (addr_len != sizeof(struct sockaddr)) 1439 return -EINVAL; 1440 strlcpy(name, uaddr->sa_data, sizeof(name)); 1441 1442 dev = dev_get_by_name(sock_net(sk), name); 1443 if (dev) { 1444 err = packet_do_bind(sk, dev, pkt_sk(sk)->num); 1445 dev_put(dev); 1446 } 1447 return err; 1448 } 1449 1450 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) 1451 { 1452 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr; 1453 struct sock *sk = sock->sk; 1454 struct net_device *dev = NULL; 1455 int err; 1456 1457 1458 /* 1459 * Check legality 1460 */ 1461 1462 if (addr_len < sizeof(struct sockaddr_ll)) 1463 return -EINVAL; 1464 if (sll->sll_family != AF_PACKET) 1465 return -EINVAL; 1466 1467 if (sll->sll_ifindex) { 1468 err = -ENODEV; 1469 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex); 1470 if (dev == NULL) 1471 goto out; 1472 } 1473 err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num); 1474 if (dev) 1475 dev_put(dev); 1476 1477 out: 1478 return err; 1479 } 1480 1481 static struct proto packet_proto = { 1482 .name = "PACKET", 1483 .owner = THIS_MODULE, 1484 .obj_size = sizeof(struct packet_sock), 1485 }; 1486 1487 /* 1488 * Create a packet of type SOCK_PACKET. 1489 */ 1490 1491 static int packet_create(struct net *net, struct socket *sock, int protocol, 1492 int kern) 1493 { 1494 struct sock *sk; 1495 struct packet_sock *po; 1496 __be16 proto = (__force __be16)protocol; /* weird, but documented */ 1497 int err; 1498 1499 if (!capable(CAP_NET_RAW)) 1500 return -EPERM; 1501 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW && 1502 sock->type != SOCK_PACKET) 1503 return -ESOCKTNOSUPPORT; 1504 1505 sock->state = SS_UNCONNECTED; 1506 1507 err = -ENOBUFS; 1508 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto); 1509 if (sk == NULL) 1510 goto out; 1511 1512 sock->ops = &packet_ops; 1513 if (sock->type == SOCK_PACKET) 1514 sock->ops = &packet_ops_spkt; 1515 1516 sock_init_data(sock, sk); 1517 1518 po = pkt_sk(sk); 1519 sk->sk_family = PF_PACKET; 1520 po->num = proto; 1521 1522 sk->sk_destruct = packet_sock_destruct; 1523 sk_refcnt_debug_inc(sk); 1524 1525 /* 1526 * Attach a protocol block 1527 */ 1528 1529 spin_lock_init(&po->bind_lock); 1530 mutex_init(&po->pg_vec_lock); 1531 po->prot_hook.func = packet_rcv; 1532 1533 if (sock->type == SOCK_PACKET) 1534 po->prot_hook.func = packet_rcv_spkt; 1535 1536 po->prot_hook.af_packet_priv = sk; 1537 1538 if (proto) { 1539 po->prot_hook.type = proto; 1540 dev_add_pack(&po->prot_hook); 1541 sock_hold(sk); 1542 po->running = 1; 1543 } 1544 1545 spin_lock_bh(&net->packet.sklist_lock); 1546 sk_add_node_rcu(sk, &net->packet.sklist); 1547 sock_prot_inuse_add(net, &packet_proto, 1); 1548 spin_unlock_bh(&net->packet.sklist_lock); 1549 1550 return 0; 1551 out: 1552 return err; 1553 } 1554 1555 static int packet_recv_error(struct sock *sk, struct msghdr *msg, int len) 1556 { 1557 struct sock_exterr_skb *serr; 1558 struct sk_buff *skb, *skb2; 1559 int copied, err; 1560 1561 err = -EAGAIN; 1562 skb = skb_dequeue(&sk->sk_error_queue); 1563 if (skb == NULL) 1564 goto out; 1565 1566 copied = skb->len; 1567 if (copied > len) { 1568 msg->msg_flags |= MSG_TRUNC; 1569 copied = len; 1570 } 1571 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); 1572 if (err) 1573 goto out_free_skb; 1574 1575 sock_recv_timestamp(msg, sk, skb); 1576 1577 serr = SKB_EXT_ERR(skb); 1578 put_cmsg(msg, SOL_PACKET, PACKET_TX_TIMESTAMP, 1579 sizeof(serr->ee), &serr->ee); 1580 1581 msg->msg_flags |= MSG_ERRQUEUE; 1582 err = copied; 1583 1584 /* Reset and regenerate socket error */ 1585 spin_lock_bh(&sk->sk_error_queue.lock); 1586 sk->sk_err = 0; 1587 if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) { 1588 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno; 1589 spin_unlock_bh(&sk->sk_error_queue.lock); 1590 sk->sk_error_report(sk); 1591 } else 1592 spin_unlock_bh(&sk->sk_error_queue.lock); 1593 1594 out_free_skb: 1595 kfree_skb(skb); 1596 out: 1597 return err; 1598 } 1599 1600 /* 1601 * Pull a packet from our receive queue and hand it to the user. 1602 * If necessary we block. 1603 */ 1604 1605 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock, 1606 struct msghdr *msg, size_t len, int flags) 1607 { 1608 struct sock *sk = sock->sk; 1609 struct sk_buff *skb; 1610 int copied, err; 1611 struct sockaddr_ll *sll; 1612 int vnet_hdr_len = 0; 1613 1614 err = -EINVAL; 1615 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE)) 1616 goto out; 1617 1618 #if 0 1619 /* What error should we return now? EUNATTACH? */ 1620 if (pkt_sk(sk)->ifindex < 0) 1621 return -ENODEV; 1622 #endif 1623 1624 if (flags & MSG_ERRQUEUE) { 1625 err = packet_recv_error(sk, msg, len); 1626 goto out; 1627 } 1628 1629 /* 1630 * Call the generic datagram receiver. This handles all sorts 1631 * of horrible races and re-entrancy so we can forget about it 1632 * in the protocol layers. 1633 * 1634 * Now it will return ENETDOWN, if device have just gone down, 1635 * but then it will block. 1636 */ 1637 1638 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err); 1639 1640 /* 1641 * An error occurred so return it. Because skb_recv_datagram() 1642 * handles the blocking we don't see and worry about blocking 1643 * retries. 1644 */ 1645 1646 if (skb == NULL) 1647 goto out; 1648 1649 if (pkt_sk(sk)->has_vnet_hdr) { 1650 struct virtio_net_hdr vnet_hdr = { 0 }; 1651 1652 err = -EINVAL; 1653 vnet_hdr_len = sizeof(vnet_hdr); 1654 if (len < vnet_hdr_len) 1655 goto out_free; 1656 1657 len -= vnet_hdr_len; 1658 1659 if (skb_is_gso(skb)) { 1660 struct skb_shared_info *sinfo = skb_shinfo(skb); 1661 1662 /* This is a hint as to how much should be linear. */ 1663 vnet_hdr.hdr_len = skb_headlen(skb); 1664 vnet_hdr.gso_size = sinfo->gso_size; 1665 if (sinfo->gso_type & SKB_GSO_TCPV4) 1666 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4; 1667 else if (sinfo->gso_type & SKB_GSO_TCPV6) 1668 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6; 1669 else if (sinfo->gso_type & SKB_GSO_UDP) 1670 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP; 1671 else if (sinfo->gso_type & SKB_GSO_FCOE) 1672 goto out_free; 1673 else 1674 BUG(); 1675 if (sinfo->gso_type & SKB_GSO_TCP_ECN) 1676 vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN; 1677 } else 1678 vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE; 1679 1680 if (skb->ip_summed == CHECKSUM_PARTIAL) { 1681 vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; 1682 vnet_hdr.csum_start = skb_checksum_start_offset(skb); 1683 vnet_hdr.csum_offset = skb->csum_offset; 1684 } /* else everything is zero */ 1685 1686 err = memcpy_toiovec(msg->msg_iov, (void *)&vnet_hdr, 1687 vnet_hdr_len); 1688 if (err < 0) 1689 goto out_free; 1690 } 1691 1692 /* 1693 * If the address length field is there to be filled in, we fill 1694 * it in now. 1695 */ 1696 1697 sll = &PACKET_SKB_CB(skb)->sa.ll; 1698 if (sock->type == SOCK_PACKET) 1699 msg->msg_namelen = sizeof(struct sockaddr_pkt); 1700 else 1701 msg->msg_namelen = sll->sll_halen + offsetof(struct sockaddr_ll, sll_addr); 1702 1703 /* 1704 * You lose any data beyond the buffer you gave. If it worries a 1705 * user program they can ask the device for its MTU anyway. 1706 */ 1707 1708 copied = skb->len; 1709 if (copied > len) { 1710 copied = len; 1711 msg->msg_flags |= MSG_TRUNC; 1712 } 1713 1714 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); 1715 if (err) 1716 goto out_free; 1717 1718 sock_recv_ts_and_drops(msg, sk, skb); 1719 1720 if (msg->msg_name) 1721 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa, 1722 msg->msg_namelen); 1723 1724 if (pkt_sk(sk)->auxdata) { 1725 struct tpacket_auxdata aux; 1726 1727 aux.tp_status = TP_STATUS_USER; 1728 if (skb->ip_summed == CHECKSUM_PARTIAL) 1729 aux.tp_status |= TP_STATUS_CSUMNOTREADY; 1730 aux.tp_len = PACKET_SKB_CB(skb)->origlen; 1731 aux.tp_snaplen = skb->len; 1732 aux.tp_mac = 0; 1733 aux.tp_net = skb_network_offset(skb); 1734 if (vlan_tx_tag_present(skb)) { 1735 aux.tp_vlan_tci = vlan_tx_tag_get(skb); 1736 aux.tp_status |= TP_STATUS_VLAN_VALID; 1737 } else { 1738 aux.tp_vlan_tci = 0; 1739 } 1740 aux.tp_padding = 0; 1741 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux); 1742 } 1743 1744 /* 1745 * Free or return the buffer as appropriate. Again this 1746 * hides all the races and re-entrancy issues from us. 1747 */ 1748 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied); 1749 1750 out_free: 1751 skb_free_datagram(sk, skb); 1752 out: 1753 return err; 1754 } 1755 1756 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr, 1757 int *uaddr_len, int peer) 1758 { 1759 struct net_device *dev; 1760 struct sock *sk = sock->sk; 1761 1762 if (peer) 1763 return -EOPNOTSUPP; 1764 1765 uaddr->sa_family = AF_PACKET; 1766 rcu_read_lock(); 1767 dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex); 1768 if (dev) 1769 strncpy(uaddr->sa_data, dev->name, 14); 1770 else 1771 memset(uaddr->sa_data, 0, 14); 1772 rcu_read_unlock(); 1773 *uaddr_len = sizeof(*uaddr); 1774 1775 return 0; 1776 } 1777 1778 static int packet_getname(struct socket *sock, struct sockaddr *uaddr, 1779 int *uaddr_len, int peer) 1780 { 1781 struct net_device *dev; 1782 struct sock *sk = sock->sk; 1783 struct packet_sock *po = pkt_sk(sk); 1784 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr); 1785 1786 if (peer) 1787 return -EOPNOTSUPP; 1788 1789 sll->sll_family = AF_PACKET; 1790 sll->sll_ifindex = po->ifindex; 1791 sll->sll_protocol = po->num; 1792 sll->sll_pkttype = 0; 1793 rcu_read_lock(); 1794 dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex); 1795 if (dev) { 1796 sll->sll_hatype = dev->type; 1797 sll->sll_halen = dev->addr_len; 1798 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len); 1799 } else { 1800 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */ 1801 sll->sll_halen = 0; 1802 } 1803 rcu_read_unlock(); 1804 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen; 1805 1806 return 0; 1807 } 1808 1809 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i, 1810 int what) 1811 { 1812 switch (i->type) { 1813 case PACKET_MR_MULTICAST: 1814 if (i->alen != dev->addr_len) 1815 return -EINVAL; 1816 if (what > 0) 1817 return dev_mc_add(dev, i->addr); 1818 else 1819 return dev_mc_del(dev, i->addr); 1820 break; 1821 case PACKET_MR_PROMISC: 1822 return dev_set_promiscuity(dev, what); 1823 break; 1824 case PACKET_MR_ALLMULTI: 1825 return dev_set_allmulti(dev, what); 1826 break; 1827 case PACKET_MR_UNICAST: 1828 if (i->alen != dev->addr_len) 1829 return -EINVAL; 1830 if (what > 0) 1831 return dev_uc_add(dev, i->addr); 1832 else 1833 return dev_uc_del(dev, i->addr); 1834 break; 1835 default: 1836 break; 1837 } 1838 return 0; 1839 } 1840 1841 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what) 1842 { 1843 for ( ; i; i = i->next) { 1844 if (i->ifindex == dev->ifindex) 1845 packet_dev_mc(dev, i, what); 1846 } 1847 } 1848 1849 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq) 1850 { 1851 struct packet_sock *po = pkt_sk(sk); 1852 struct packet_mclist *ml, *i; 1853 struct net_device *dev; 1854 int err; 1855 1856 rtnl_lock(); 1857 1858 err = -ENODEV; 1859 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex); 1860 if (!dev) 1861 goto done; 1862 1863 err = -EINVAL; 1864 if (mreq->mr_alen > dev->addr_len) 1865 goto done; 1866 1867 err = -ENOBUFS; 1868 i = kmalloc(sizeof(*i), GFP_KERNEL); 1869 if (i == NULL) 1870 goto done; 1871 1872 err = 0; 1873 for (ml = po->mclist; ml; ml = ml->next) { 1874 if (ml->ifindex == mreq->mr_ifindex && 1875 ml->type == mreq->mr_type && 1876 ml->alen == mreq->mr_alen && 1877 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) { 1878 ml->count++; 1879 /* Free the new element ... */ 1880 kfree(i); 1881 goto done; 1882 } 1883 } 1884 1885 i->type = mreq->mr_type; 1886 i->ifindex = mreq->mr_ifindex; 1887 i->alen = mreq->mr_alen; 1888 memcpy(i->addr, mreq->mr_address, i->alen); 1889 i->count = 1; 1890 i->next = po->mclist; 1891 po->mclist = i; 1892 err = packet_dev_mc(dev, i, 1); 1893 if (err) { 1894 po->mclist = i->next; 1895 kfree(i); 1896 } 1897 1898 done: 1899 rtnl_unlock(); 1900 return err; 1901 } 1902 1903 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq) 1904 { 1905 struct packet_mclist *ml, **mlp; 1906 1907 rtnl_lock(); 1908 1909 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) { 1910 if (ml->ifindex == mreq->mr_ifindex && 1911 ml->type == mreq->mr_type && 1912 ml->alen == mreq->mr_alen && 1913 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) { 1914 if (--ml->count == 0) { 1915 struct net_device *dev; 1916 *mlp = ml->next; 1917 dev = __dev_get_by_index(sock_net(sk), ml->ifindex); 1918 if (dev) 1919 packet_dev_mc(dev, ml, -1); 1920 kfree(ml); 1921 } 1922 rtnl_unlock(); 1923 return 0; 1924 } 1925 } 1926 rtnl_unlock(); 1927 return -EADDRNOTAVAIL; 1928 } 1929 1930 static void packet_flush_mclist(struct sock *sk) 1931 { 1932 struct packet_sock *po = pkt_sk(sk); 1933 struct packet_mclist *ml; 1934 1935 if (!po->mclist) 1936 return; 1937 1938 rtnl_lock(); 1939 while ((ml = po->mclist) != NULL) { 1940 struct net_device *dev; 1941 1942 po->mclist = ml->next; 1943 dev = __dev_get_by_index(sock_net(sk), ml->ifindex); 1944 if (dev != NULL) 1945 packet_dev_mc(dev, ml, -1); 1946 kfree(ml); 1947 } 1948 rtnl_unlock(); 1949 } 1950 1951 static int 1952 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen) 1953 { 1954 struct sock *sk = sock->sk; 1955 struct packet_sock *po = pkt_sk(sk); 1956 int ret; 1957 1958 if (level != SOL_PACKET) 1959 return -ENOPROTOOPT; 1960 1961 switch (optname) { 1962 case PACKET_ADD_MEMBERSHIP: 1963 case PACKET_DROP_MEMBERSHIP: 1964 { 1965 struct packet_mreq_max mreq; 1966 int len = optlen; 1967 memset(&mreq, 0, sizeof(mreq)); 1968 if (len < sizeof(struct packet_mreq)) 1969 return -EINVAL; 1970 if (len > sizeof(mreq)) 1971 len = sizeof(mreq); 1972 if (copy_from_user(&mreq, optval, len)) 1973 return -EFAULT; 1974 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address))) 1975 return -EINVAL; 1976 if (optname == PACKET_ADD_MEMBERSHIP) 1977 ret = packet_mc_add(sk, &mreq); 1978 else 1979 ret = packet_mc_drop(sk, &mreq); 1980 return ret; 1981 } 1982 1983 case PACKET_RX_RING: 1984 case PACKET_TX_RING: 1985 { 1986 struct tpacket_req req; 1987 1988 if (optlen < sizeof(req)) 1989 return -EINVAL; 1990 if (pkt_sk(sk)->has_vnet_hdr) 1991 return -EINVAL; 1992 if (copy_from_user(&req, optval, sizeof(req))) 1993 return -EFAULT; 1994 return packet_set_ring(sk, &req, 0, optname == PACKET_TX_RING); 1995 } 1996 case PACKET_COPY_THRESH: 1997 { 1998 int val; 1999 2000 if (optlen != sizeof(val)) 2001 return -EINVAL; 2002 if (copy_from_user(&val, optval, sizeof(val))) 2003 return -EFAULT; 2004 2005 pkt_sk(sk)->copy_thresh = val; 2006 return 0; 2007 } 2008 case PACKET_VERSION: 2009 { 2010 int val; 2011 2012 if (optlen != sizeof(val)) 2013 return -EINVAL; 2014 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 2015 return -EBUSY; 2016 if (copy_from_user(&val, optval, sizeof(val))) 2017 return -EFAULT; 2018 switch (val) { 2019 case TPACKET_V1: 2020 case TPACKET_V2: 2021 po->tp_version = val; 2022 return 0; 2023 default: 2024 return -EINVAL; 2025 } 2026 } 2027 case PACKET_RESERVE: 2028 { 2029 unsigned int val; 2030 2031 if (optlen != sizeof(val)) 2032 return -EINVAL; 2033 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 2034 return -EBUSY; 2035 if (copy_from_user(&val, optval, sizeof(val))) 2036 return -EFAULT; 2037 po->tp_reserve = val; 2038 return 0; 2039 } 2040 case PACKET_LOSS: 2041 { 2042 unsigned int val; 2043 2044 if (optlen != sizeof(val)) 2045 return -EINVAL; 2046 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 2047 return -EBUSY; 2048 if (copy_from_user(&val, optval, sizeof(val))) 2049 return -EFAULT; 2050 po->tp_loss = !!val; 2051 return 0; 2052 } 2053 case PACKET_AUXDATA: 2054 { 2055 int val; 2056 2057 if (optlen < sizeof(val)) 2058 return -EINVAL; 2059 if (copy_from_user(&val, optval, sizeof(val))) 2060 return -EFAULT; 2061 2062 po->auxdata = !!val; 2063 return 0; 2064 } 2065 case PACKET_ORIGDEV: 2066 { 2067 int val; 2068 2069 if (optlen < sizeof(val)) 2070 return -EINVAL; 2071 if (copy_from_user(&val, optval, sizeof(val))) 2072 return -EFAULT; 2073 2074 po->origdev = !!val; 2075 return 0; 2076 } 2077 case PACKET_VNET_HDR: 2078 { 2079 int val; 2080 2081 if (sock->type != SOCK_RAW) 2082 return -EINVAL; 2083 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) 2084 return -EBUSY; 2085 if (optlen < sizeof(val)) 2086 return -EINVAL; 2087 if (copy_from_user(&val, optval, sizeof(val))) 2088 return -EFAULT; 2089 2090 po->has_vnet_hdr = !!val; 2091 return 0; 2092 } 2093 case PACKET_TIMESTAMP: 2094 { 2095 int val; 2096 2097 if (optlen != sizeof(val)) 2098 return -EINVAL; 2099 if (copy_from_user(&val, optval, sizeof(val))) 2100 return -EFAULT; 2101 2102 po->tp_tstamp = val; 2103 return 0; 2104 } 2105 default: 2106 return -ENOPROTOOPT; 2107 } 2108 } 2109 2110 static int packet_getsockopt(struct socket *sock, int level, int optname, 2111 char __user *optval, int __user *optlen) 2112 { 2113 int len; 2114 int val; 2115 struct sock *sk = sock->sk; 2116 struct packet_sock *po = pkt_sk(sk); 2117 void *data; 2118 struct tpacket_stats st; 2119 2120 if (level != SOL_PACKET) 2121 return -ENOPROTOOPT; 2122 2123 if (get_user(len, optlen)) 2124 return -EFAULT; 2125 2126 if (len < 0) 2127 return -EINVAL; 2128 2129 switch (optname) { 2130 case PACKET_STATISTICS: 2131 if (len > sizeof(struct tpacket_stats)) 2132 len = sizeof(struct tpacket_stats); 2133 spin_lock_bh(&sk->sk_receive_queue.lock); 2134 st = po->stats; 2135 memset(&po->stats, 0, sizeof(st)); 2136 spin_unlock_bh(&sk->sk_receive_queue.lock); 2137 st.tp_packets += st.tp_drops; 2138 2139 data = &st; 2140 break; 2141 case PACKET_AUXDATA: 2142 if (len > sizeof(int)) 2143 len = sizeof(int); 2144 val = po->auxdata; 2145 2146 data = &val; 2147 break; 2148 case PACKET_ORIGDEV: 2149 if (len > sizeof(int)) 2150 len = sizeof(int); 2151 val = po->origdev; 2152 2153 data = &val; 2154 break; 2155 case PACKET_VNET_HDR: 2156 if (len > sizeof(int)) 2157 len = sizeof(int); 2158 val = po->has_vnet_hdr; 2159 2160 data = &val; 2161 break; 2162 case PACKET_VERSION: 2163 if (len > sizeof(int)) 2164 len = sizeof(int); 2165 val = po->tp_version; 2166 data = &val; 2167 break; 2168 case PACKET_HDRLEN: 2169 if (len > sizeof(int)) 2170 len = sizeof(int); 2171 if (copy_from_user(&val, optval, len)) 2172 return -EFAULT; 2173 switch (val) { 2174 case TPACKET_V1: 2175 val = sizeof(struct tpacket_hdr); 2176 break; 2177 case TPACKET_V2: 2178 val = sizeof(struct tpacket2_hdr); 2179 break; 2180 default: 2181 return -EINVAL; 2182 } 2183 data = &val; 2184 break; 2185 case PACKET_RESERVE: 2186 if (len > sizeof(unsigned int)) 2187 len = sizeof(unsigned int); 2188 val = po->tp_reserve; 2189 data = &val; 2190 break; 2191 case PACKET_LOSS: 2192 if (len > sizeof(unsigned int)) 2193 len = sizeof(unsigned int); 2194 val = po->tp_loss; 2195 data = &val; 2196 break; 2197 case PACKET_TIMESTAMP: 2198 if (len > sizeof(int)) 2199 len = sizeof(int); 2200 val = po->tp_tstamp; 2201 data = &val; 2202 break; 2203 default: 2204 return -ENOPROTOOPT; 2205 } 2206 2207 if (put_user(len, optlen)) 2208 return -EFAULT; 2209 if (copy_to_user(optval, data, len)) 2210 return -EFAULT; 2211 return 0; 2212 } 2213 2214 2215 static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data) 2216 { 2217 struct sock *sk; 2218 struct hlist_node *node; 2219 struct net_device *dev = data; 2220 struct net *net = dev_net(dev); 2221 2222 rcu_read_lock(); 2223 sk_for_each_rcu(sk, node, &net->packet.sklist) { 2224 struct packet_sock *po = pkt_sk(sk); 2225 2226 switch (msg) { 2227 case NETDEV_UNREGISTER: 2228 if (po->mclist) 2229 packet_dev_mclist(dev, po->mclist, -1); 2230 /* fallthrough */ 2231 2232 case NETDEV_DOWN: 2233 if (dev->ifindex == po->ifindex) { 2234 spin_lock(&po->bind_lock); 2235 if (po->running) { 2236 __dev_remove_pack(&po->prot_hook); 2237 __sock_put(sk); 2238 po->running = 0; 2239 sk->sk_err = ENETDOWN; 2240 if (!sock_flag(sk, SOCK_DEAD)) 2241 sk->sk_error_report(sk); 2242 } 2243 if (msg == NETDEV_UNREGISTER) { 2244 po->ifindex = -1; 2245 po->prot_hook.dev = NULL; 2246 } 2247 spin_unlock(&po->bind_lock); 2248 } 2249 break; 2250 case NETDEV_UP: 2251 if (dev->ifindex == po->ifindex) { 2252 spin_lock(&po->bind_lock); 2253 if (po->num && !po->running) { 2254 dev_add_pack(&po->prot_hook); 2255 sock_hold(sk); 2256 po->running = 1; 2257 } 2258 spin_unlock(&po->bind_lock); 2259 } 2260 break; 2261 } 2262 } 2263 rcu_read_unlock(); 2264 return NOTIFY_DONE; 2265 } 2266 2267 2268 static int packet_ioctl(struct socket *sock, unsigned int cmd, 2269 unsigned long arg) 2270 { 2271 struct sock *sk = sock->sk; 2272 2273 switch (cmd) { 2274 case SIOCOUTQ: 2275 { 2276 int amount = sk_wmem_alloc_get(sk); 2277 2278 return put_user(amount, (int __user *)arg); 2279 } 2280 case SIOCINQ: 2281 { 2282 struct sk_buff *skb; 2283 int amount = 0; 2284 2285 spin_lock_bh(&sk->sk_receive_queue.lock); 2286 skb = skb_peek(&sk->sk_receive_queue); 2287 if (skb) 2288 amount = skb->len; 2289 spin_unlock_bh(&sk->sk_receive_queue.lock); 2290 return put_user(amount, (int __user *)arg); 2291 } 2292 case SIOCGSTAMP: 2293 return sock_get_timestamp(sk, (struct timeval __user *)arg); 2294 case SIOCGSTAMPNS: 2295 return sock_get_timestampns(sk, (struct timespec __user *)arg); 2296 2297 #ifdef CONFIG_INET 2298 case SIOCADDRT: 2299 case SIOCDELRT: 2300 case SIOCDARP: 2301 case SIOCGARP: 2302 case SIOCSARP: 2303 case SIOCGIFADDR: 2304 case SIOCSIFADDR: 2305 case SIOCGIFBRDADDR: 2306 case SIOCSIFBRDADDR: 2307 case SIOCGIFNETMASK: 2308 case SIOCSIFNETMASK: 2309 case SIOCGIFDSTADDR: 2310 case SIOCSIFDSTADDR: 2311 case SIOCSIFFLAGS: 2312 return inet_dgram_ops.ioctl(sock, cmd, arg); 2313 #endif 2314 2315 default: 2316 return -ENOIOCTLCMD; 2317 } 2318 return 0; 2319 } 2320 2321 static unsigned int packet_poll(struct file *file, struct socket *sock, 2322 poll_table *wait) 2323 { 2324 struct sock *sk = sock->sk; 2325 struct packet_sock *po = pkt_sk(sk); 2326 unsigned int mask = datagram_poll(file, sock, wait); 2327 2328 spin_lock_bh(&sk->sk_receive_queue.lock); 2329 if (po->rx_ring.pg_vec) { 2330 if (!packet_previous_frame(po, &po->rx_ring, TP_STATUS_KERNEL)) 2331 mask |= POLLIN | POLLRDNORM; 2332 } 2333 spin_unlock_bh(&sk->sk_receive_queue.lock); 2334 spin_lock_bh(&sk->sk_write_queue.lock); 2335 if (po->tx_ring.pg_vec) { 2336 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE)) 2337 mask |= POLLOUT | POLLWRNORM; 2338 } 2339 spin_unlock_bh(&sk->sk_write_queue.lock); 2340 return mask; 2341 } 2342 2343 2344 /* Dirty? Well, I still did not learn better way to account 2345 * for user mmaps. 2346 */ 2347 2348 static void packet_mm_open(struct vm_area_struct *vma) 2349 { 2350 struct file *file = vma->vm_file; 2351 struct socket *sock = file->private_data; 2352 struct sock *sk = sock->sk; 2353 2354 if (sk) 2355 atomic_inc(&pkt_sk(sk)->mapped); 2356 } 2357 2358 static void packet_mm_close(struct vm_area_struct *vma) 2359 { 2360 struct file *file = vma->vm_file; 2361 struct socket *sock = file->private_data; 2362 struct sock *sk = sock->sk; 2363 2364 if (sk) 2365 atomic_dec(&pkt_sk(sk)->mapped); 2366 } 2367 2368 static const struct vm_operations_struct packet_mmap_ops = { 2369 .open = packet_mm_open, 2370 .close = packet_mm_close, 2371 }; 2372 2373 static void free_pg_vec(struct pgv *pg_vec, unsigned int order, 2374 unsigned int len) 2375 { 2376 int i; 2377 2378 for (i = 0; i < len; i++) { 2379 if (likely(pg_vec[i].buffer)) { 2380 if (is_vmalloc_addr(pg_vec[i].buffer)) 2381 vfree(pg_vec[i].buffer); 2382 else 2383 free_pages((unsigned long)pg_vec[i].buffer, 2384 order); 2385 pg_vec[i].buffer = NULL; 2386 } 2387 } 2388 kfree(pg_vec); 2389 } 2390 2391 static inline char *alloc_one_pg_vec_page(unsigned long order) 2392 { 2393 char *buffer = NULL; 2394 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP | 2395 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY; 2396 2397 buffer = (char *) __get_free_pages(gfp_flags, order); 2398 2399 if (buffer) 2400 return buffer; 2401 2402 /* 2403 * __get_free_pages failed, fall back to vmalloc 2404 */ 2405 buffer = vzalloc((1 << order) * PAGE_SIZE); 2406 2407 if (buffer) 2408 return buffer; 2409 2410 /* 2411 * vmalloc failed, lets dig into swap here 2412 */ 2413 gfp_flags &= ~__GFP_NORETRY; 2414 buffer = (char *)__get_free_pages(gfp_flags, order); 2415 if (buffer) 2416 return buffer; 2417 2418 /* 2419 * complete and utter failure 2420 */ 2421 return NULL; 2422 } 2423 2424 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order) 2425 { 2426 unsigned int block_nr = req->tp_block_nr; 2427 struct pgv *pg_vec; 2428 int i; 2429 2430 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL); 2431 if (unlikely(!pg_vec)) 2432 goto out; 2433 2434 for (i = 0; i < block_nr; i++) { 2435 pg_vec[i].buffer = alloc_one_pg_vec_page(order); 2436 if (unlikely(!pg_vec[i].buffer)) 2437 goto out_free_pgvec; 2438 } 2439 2440 out: 2441 return pg_vec; 2442 2443 out_free_pgvec: 2444 free_pg_vec(pg_vec, order, block_nr); 2445 pg_vec = NULL; 2446 goto out; 2447 } 2448 2449 static int packet_set_ring(struct sock *sk, struct tpacket_req *req, 2450 int closing, int tx_ring) 2451 { 2452 struct pgv *pg_vec = NULL; 2453 struct packet_sock *po = pkt_sk(sk); 2454 int was_running, order = 0; 2455 struct packet_ring_buffer *rb; 2456 struct sk_buff_head *rb_queue; 2457 __be16 num; 2458 int err; 2459 2460 rb = tx_ring ? &po->tx_ring : &po->rx_ring; 2461 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue; 2462 2463 err = -EBUSY; 2464 if (!closing) { 2465 if (atomic_read(&po->mapped)) 2466 goto out; 2467 if (atomic_read(&rb->pending)) 2468 goto out; 2469 } 2470 2471 if (req->tp_block_nr) { 2472 /* Sanity tests and some calculations */ 2473 err = -EBUSY; 2474 if (unlikely(rb->pg_vec)) 2475 goto out; 2476 2477 switch (po->tp_version) { 2478 case TPACKET_V1: 2479 po->tp_hdrlen = TPACKET_HDRLEN; 2480 break; 2481 case TPACKET_V2: 2482 po->tp_hdrlen = TPACKET2_HDRLEN; 2483 break; 2484 } 2485 2486 err = -EINVAL; 2487 if (unlikely((int)req->tp_block_size <= 0)) 2488 goto out; 2489 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1))) 2490 goto out; 2491 if (unlikely(req->tp_frame_size < po->tp_hdrlen + 2492 po->tp_reserve)) 2493 goto out; 2494 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1))) 2495 goto out; 2496 2497 rb->frames_per_block = req->tp_block_size/req->tp_frame_size; 2498 if (unlikely(rb->frames_per_block <= 0)) 2499 goto out; 2500 if (unlikely((rb->frames_per_block * req->tp_block_nr) != 2501 req->tp_frame_nr)) 2502 goto out; 2503 2504 err = -ENOMEM; 2505 order = get_order(req->tp_block_size); 2506 pg_vec = alloc_pg_vec(req, order); 2507 if (unlikely(!pg_vec)) 2508 goto out; 2509 } 2510 /* Done */ 2511 else { 2512 err = -EINVAL; 2513 if (unlikely(req->tp_frame_nr)) 2514 goto out; 2515 } 2516 2517 lock_sock(sk); 2518 2519 /* Detach socket from network */ 2520 spin_lock(&po->bind_lock); 2521 was_running = po->running; 2522 num = po->num; 2523 if (was_running) { 2524 __dev_remove_pack(&po->prot_hook); 2525 po->num = 0; 2526 po->running = 0; 2527 __sock_put(sk); 2528 } 2529 spin_unlock(&po->bind_lock); 2530 2531 synchronize_net(); 2532 2533 err = -EBUSY; 2534 mutex_lock(&po->pg_vec_lock); 2535 if (closing || atomic_read(&po->mapped) == 0) { 2536 err = 0; 2537 spin_lock_bh(&rb_queue->lock); 2538 swap(rb->pg_vec, pg_vec); 2539 rb->frame_max = (req->tp_frame_nr - 1); 2540 rb->head = 0; 2541 rb->frame_size = req->tp_frame_size; 2542 spin_unlock_bh(&rb_queue->lock); 2543 2544 swap(rb->pg_vec_order, order); 2545 swap(rb->pg_vec_len, req->tp_block_nr); 2546 2547 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE; 2548 po->prot_hook.func = (po->rx_ring.pg_vec) ? 2549 tpacket_rcv : packet_rcv; 2550 skb_queue_purge(rb_queue); 2551 if (atomic_read(&po->mapped)) 2552 pr_err("packet_mmap: vma is busy: %d\n", 2553 atomic_read(&po->mapped)); 2554 } 2555 mutex_unlock(&po->pg_vec_lock); 2556 2557 spin_lock(&po->bind_lock); 2558 if (was_running && !po->running) { 2559 sock_hold(sk); 2560 po->running = 1; 2561 po->num = num; 2562 dev_add_pack(&po->prot_hook); 2563 } 2564 spin_unlock(&po->bind_lock); 2565 2566 release_sock(sk); 2567 2568 if (pg_vec) 2569 free_pg_vec(pg_vec, order, req->tp_block_nr); 2570 out: 2571 return err; 2572 } 2573 2574 static int packet_mmap(struct file *file, struct socket *sock, 2575 struct vm_area_struct *vma) 2576 { 2577 struct sock *sk = sock->sk; 2578 struct packet_sock *po = pkt_sk(sk); 2579 unsigned long size, expected_size; 2580 struct packet_ring_buffer *rb; 2581 unsigned long start; 2582 int err = -EINVAL; 2583 int i; 2584 2585 if (vma->vm_pgoff) 2586 return -EINVAL; 2587 2588 mutex_lock(&po->pg_vec_lock); 2589 2590 expected_size = 0; 2591 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) { 2592 if (rb->pg_vec) { 2593 expected_size += rb->pg_vec_len 2594 * rb->pg_vec_pages 2595 * PAGE_SIZE; 2596 } 2597 } 2598 2599 if (expected_size == 0) 2600 goto out; 2601 2602 size = vma->vm_end - vma->vm_start; 2603 if (size != expected_size) 2604 goto out; 2605 2606 start = vma->vm_start; 2607 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) { 2608 if (rb->pg_vec == NULL) 2609 continue; 2610 2611 for (i = 0; i < rb->pg_vec_len; i++) { 2612 struct page *page; 2613 void *kaddr = rb->pg_vec[i].buffer; 2614 int pg_num; 2615 2616 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) { 2617 page = pgv_to_page(kaddr); 2618 err = vm_insert_page(vma, start, page); 2619 if (unlikely(err)) 2620 goto out; 2621 start += PAGE_SIZE; 2622 kaddr += PAGE_SIZE; 2623 } 2624 } 2625 } 2626 2627 atomic_inc(&po->mapped); 2628 vma->vm_ops = &packet_mmap_ops; 2629 err = 0; 2630 2631 out: 2632 mutex_unlock(&po->pg_vec_lock); 2633 return err; 2634 } 2635 2636 static const struct proto_ops packet_ops_spkt = { 2637 .family = PF_PACKET, 2638 .owner = THIS_MODULE, 2639 .release = packet_release, 2640 .bind = packet_bind_spkt, 2641 .connect = sock_no_connect, 2642 .socketpair = sock_no_socketpair, 2643 .accept = sock_no_accept, 2644 .getname = packet_getname_spkt, 2645 .poll = datagram_poll, 2646 .ioctl = packet_ioctl, 2647 .listen = sock_no_listen, 2648 .shutdown = sock_no_shutdown, 2649 .setsockopt = sock_no_setsockopt, 2650 .getsockopt = sock_no_getsockopt, 2651 .sendmsg = packet_sendmsg_spkt, 2652 .recvmsg = packet_recvmsg, 2653 .mmap = sock_no_mmap, 2654 .sendpage = sock_no_sendpage, 2655 }; 2656 2657 static const struct proto_ops packet_ops = { 2658 .family = PF_PACKET, 2659 .owner = THIS_MODULE, 2660 .release = packet_release, 2661 .bind = packet_bind, 2662 .connect = sock_no_connect, 2663 .socketpair = sock_no_socketpair, 2664 .accept = sock_no_accept, 2665 .getname = packet_getname, 2666 .poll = packet_poll, 2667 .ioctl = packet_ioctl, 2668 .listen = sock_no_listen, 2669 .shutdown = sock_no_shutdown, 2670 .setsockopt = packet_setsockopt, 2671 .getsockopt = packet_getsockopt, 2672 .sendmsg = packet_sendmsg, 2673 .recvmsg = packet_recvmsg, 2674 .mmap = packet_mmap, 2675 .sendpage = sock_no_sendpage, 2676 }; 2677 2678 static const struct net_proto_family packet_family_ops = { 2679 .family = PF_PACKET, 2680 .create = packet_create, 2681 .owner = THIS_MODULE, 2682 }; 2683 2684 static struct notifier_block packet_netdev_notifier = { 2685 .notifier_call = packet_notifier, 2686 }; 2687 2688 #ifdef CONFIG_PROC_FS 2689 2690 static void *packet_seq_start(struct seq_file *seq, loff_t *pos) 2691 __acquires(RCU) 2692 { 2693 struct net *net = seq_file_net(seq); 2694 2695 rcu_read_lock(); 2696 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos); 2697 } 2698 2699 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2700 { 2701 struct net *net = seq_file_net(seq); 2702 return seq_hlist_next_rcu(v, &net->packet.sklist, pos); 2703 } 2704 2705 static void packet_seq_stop(struct seq_file *seq, void *v) 2706 __releases(RCU) 2707 { 2708 rcu_read_unlock(); 2709 } 2710 2711 static int packet_seq_show(struct seq_file *seq, void *v) 2712 { 2713 if (v == SEQ_START_TOKEN) 2714 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n"); 2715 else { 2716 struct sock *s = sk_entry(v); 2717 const struct packet_sock *po = pkt_sk(s); 2718 2719 seq_printf(seq, 2720 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n", 2721 s, 2722 atomic_read(&s->sk_refcnt), 2723 s->sk_type, 2724 ntohs(po->num), 2725 po->ifindex, 2726 po->running, 2727 atomic_read(&s->sk_rmem_alloc), 2728 sock_i_uid(s), 2729 sock_i_ino(s)); 2730 } 2731 2732 return 0; 2733 } 2734 2735 static const struct seq_operations packet_seq_ops = { 2736 .start = packet_seq_start, 2737 .next = packet_seq_next, 2738 .stop = packet_seq_stop, 2739 .show = packet_seq_show, 2740 }; 2741 2742 static int packet_seq_open(struct inode *inode, struct file *file) 2743 { 2744 return seq_open_net(inode, file, &packet_seq_ops, 2745 sizeof(struct seq_net_private)); 2746 } 2747 2748 static const struct file_operations packet_seq_fops = { 2749 .owner = THIS_MODULE, 2750 .open = packet_seq_open, 2751 .read = seq_read, 2752 .llseek = seq_lseek, 2753 .release = seq_release_net, 2754 }; 2755 2756 #endif 2757 2758 static int __net_init packet_net_init(struct net *net) 2759 { 2760 spin_lock_init(&net->packet.sklist_lock); 2761 INIT_HLIST_HEAD(&net->packet.sklist); 2762 2763 if (!proc_net_fops_create(net, "packet", 0, &packet_seq_fops)) 2764 return -ENOMEM; 2765 2766 return 0; 2767 } 2768 2769 static void __net_exit packet_net_exit(struct net *net) 2770 { 2771 proc_net_remove(net, "packet"); 2772 } 2773 2774 static struct pernet_operations packet_net_ops = { 2775 .init = packet_net_init, 2776 .exit = packet_net_exit, 2777 }; 2778 2779 2780 static void __exit packet_exit(void) 2781 { 2782 unregister_netdevice_notifier(&packet_netdev_notifier); 2783 unregister_pernet_subsys(&packet_net_ops); 2784 sock_unregister(PF_PACKET); 2785 proto_unregister(&packet_proto); 2786 } 2787 2788 static int __init packet_init(void) 2789 { 2790 int rc = proto_register(&packet_proto, 0); 2791 2792 if (rc != 0) 2793 goto out; 2794 2795 sock_register(&packet_family_ops); 2796 register_pernet_subsys(&packet_net_ops); 2797 register_netdevice_notifier(&packet_netdev_notifier); 2798 out: 2799 return rc; 2800 } 2801 2802 module_init(packet_init); 2803 module_exit(packet_exit); 2804 MODULE_LICENSE("GPL"); 2805 MODULE_ALIAS_NETPROTO(PF_PACKET); 2806