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