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 * 43 * This program is free software; you can redistribute it and/or 44 * modify it under the terms of the GNU General Public License 45 * as published by the Free Software Foundation; either version 46 * 2 of the License, or (at your option) any later version. 47 * 48 */ 49 50 #include <linux/types.h> 51 #include <linux/mm.h> 52 #include <linux/capability.h> 53 #include <linux/fcntl.h> 54 #include <linux/socket.h> 55 #include <linux/in.h> 56 #include <linux/inet.h> 57 #include <linux/netdevice.h> 58 #include <linux/if_packet.h> 59 #include <linux/wireless.h> 60 #include <linux/kernel.h> 61 #include <linux/kmod.h> 62 #include <net/net_namespace.h> 63 #include <net/ip.h> 64 #include <net/protocol.h> 65 #include <linux/skbuff.h> 66 #include <net/sock.h> 67 #include <linux/errno.h> 68 #include <linux/timer.h> 69 #include <asm/system.h> 70 #include <asm/uaccess.h> 71 #include <asm/ioctls.h> 72 #include <asm/page.h> 73 #include <asm/cacheflush.h> 74 #include <asm/io.h> 75 #include <linux/proc_fs.h> 76 #include <linux/seq_file.h> 77 #include <linux/poll.h> 78 #include <linux/module.h> 79 #include <linux/init.h> 80 #include <linux/mutex.h> 81 82 #ifdef CONFIG_INET 83 #include <net/inet_common.h> 84 #endif 85 86 /* 87 Assumptions: 88 - if device has no dev->hard_header routine, it adds and removes ll header 89 inside itself. In this case ll header is invisible outside of device, 90 but higher levels still should reserve dev->hard_header_len. 91 Some devices are enough clever to reallocate skb, when header 92 will not fit to reserved space (tunnel), another ones are silly 93 (PPP). 94 - packet socket receives packets with pulled ll header, 95 so that SOCK_RAW should push it back. 96 97 On receive: 98 ----------- 99 100 Incoming, dev->hard_header!=NULL 101 mac_header -> ll header 102 data -> data 103 104 Outgoing, dev->hard_header!=NULL 105 mac_header -> ll header 106 data -> ll header 107 108 Incoming, dev->hard_header==NULL 109 mac_header -> UNKNOWN position. It is very likely, that it points to ll 110 header. PPP makes it, that is wrong, because introduce 111 assymetry between rx and tx paths. 112 data -> data 113 114 Outgoing, dev->hard_header==NULL 115 mac_header -> data. ll header is still not built! 116 data -> data 117 118 Resume 119 If dev->hard_header==NULL we are unlikely to restore sensible ll header. 120 121 122 On transmit: 123 ------------ 124 125 dev->hard_header != NULL 126 mac_header -> ll header 127 data -> ll header 128 129 dev->hard_header == NULL (ll header is added by device, we cannot control it) 130 mac_header -> data 131 data -> data 132 133 We should set nh.raw on output to correct posistion, 134 packet classifier depends on it. 135 */ 136 137 /* Private packet socket structures. */ 138 139 struct packet_mclist 140 { 141 struct packet_mclist *next; 142 int ifindex; 143 int count; 144 unsigned short type; 145 unsigned short alen; 146 unsigned char addr[MAX_ADDR_LEN]; 147 }; 148 /* identical to struct packet_mreq except it has 149 * a longer address field. 150 */ 151 struct packet_mreq_max 152 { 153 int mr_ifindex; 154 unsigned short mr_type; 155 unsigned short mr_alen; 156 unsigned char mr_address[MAX_ADDR_LEN]; 157 }; 158 159 #ifdef CONFIG_PACKET_MMAP 160 static int packet_set_ring(struct sock *sk, struct tpacket_req *req, int closing); 161 #endif 162 163 static void packet_flush_mclist(struct sock *sk); 164 165 struct packet_sock { 166 /* struct sock has to be the first member of packet_sock */ 167 struct sock sk; 168 struct tpacket_stats stats; 169 #ifdef CONFIG_PACKET_MMAP 170 char * *pg_vec; 171 unsigned int head; 172 unsigned int frames_per_block; 173 unsigned int frame_size; 174 unsigned int frame_max; 175 int copy_thresh; 176 #endif 177 struct packet_type prot_hook; 178 spinlock_t bind_lock; 179 struct mutex pg_vec_lock; 180 unsigned int running:1, /* prot_hook is attached*/ 181 auxdata:1, 182 origdev:1; 183 int ifindex; /* bound device */ 184 __be16 num; 185 struct packet_mclist *mclist; 186 #ifdef CONFIG_PACKET_MMAP 187 atomic_t mapped; 188 unsigned int pg_vec_order; 189 unsigned int pg_vec_pages; 190 unsigned int pg_vec_len; 191 enum tpacket_versions tp_version; 192 unsigned int tp_hdrlen; 193 unsigned int tp_reserve; 194 #endif 195 }; 196 197 struct packet_skb_cb { 198 unsigned int origlen; 199 union { 200 struct sockaddr_pkt pkt; 201 struct sockaddr_ll ll; 202 } sa; 203 }; 204 205 #define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb)) 206 207 #ifdef CONFIG_PACKET_MMAP 208 209 static void *packet_lookup_frame(struct packet_sock *po, unsigned int position, 210 int status) 211 { 212 unsigned int pg_vec_pos, frame_offset; 213 union { 214 struct tpacket_hdr *h1; 215 struct tpacket2_hdr *h2; 216 void *raw; 217 } h; 218 219 pg_vec_pos = position / po->frames_per_block; 220 frame_offset = position % po->frames_per_block; 221 222 h.raw = po->pg_vec[pg_vec_pos] + (frame_offset * po->frame_size); 223 switch (po->tp_version) { 224 case TPACKET_V1: 225 if (status != (h.h1->tp_status ? TP_STATUS_USER : 226 TP_STATUS_KERNEL)) 227 return NULL; 228 break; 229 case TPACKET_V2: 230 if (status != (h.h2->tp_status ? TP_STATUS_USER : 231 TP_STATUS_KERNEL)) 232 return NULL; 233 break; 234 } 235 return h.raw; 236 } 237 238 static void __packet_set_status(struct packet_sock *po, void *frame, int status) 239 { 240 union { 241 struct tpacket_hdr *h1; 242 struct tpacket2_hdr *h2; 243 void *raw; 244 } h; 245 246 h.raw = frame; 247 switch (po->tp_version) { 248 case TPACKET_V1: 249 h.h1->tp_status = status; 250 break; 251 case TPACKET_V2: 252 h.h2->tp_status = status; 253 break; 254 } 255 } 256 #endif 257 258 static inline struct packet_sock *pkt_sk(struct sock *sk) 259 { 260 return (struct packet_sock *)sk; 261 } 262 263 static void packet_sock_destruct(struct sock *sk) 264 { 265 WARN_ON(atomic_read(&sk->sk_rmem_alloc)); 266 WARN_ON(atomic_read(&sk->sk_wmem_alloc)); 267 268 if (!sock_flag(sk, SOCK_DEAD)) { 269 printk("Attempt to release alive packet socket: %p\n", sk); 270 return; 271 } 272 273 sk_refcnt_debug_dec(sk); 274 } 275 276 277 static const struct proto_ops packet_ops; 278 279 static const struct proto_ops packet_ops_spkt; 280 281 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) 282 { 283 struct sock *sk; 284 struct sockaddr_pkt *spkt; 285 286 /* 287 * When we registered the protocol we saved the socket in the data 288 * field for just this event. 289 */ 290 291 sk = pt->af_packet_priv; 292 293 /* 294 * Yank back the headers [hope the device set this 295 * right or kerboom...] 296 * 297 * Incoming packets have ll header pulled, 298 * push it back. 299 * 300 * For outgoing ones skb->data == skb_mac_header(skb) 301 * so that this procedure is noop. 302 */ 303 304 if (skb->pkt_type == PACKET_LOOPBACK) 305 goto out; 306 307 if (dev_net(dev) != sock_net(sk)) 308 goto out; 309 310 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) 311 goto oom; 312 313 /* drop any routing info */ 314 dst_release(skb->dst); 315 skb->dst = NULL; 316 317 /* drop conntrack reference */ 318 nf_reset(skb); 319 320 spkt = &PACKET_SKB_CB(skb)->sa.pkt; 321 322 skb_push(skb, skb->data - skb_mac_header(skb)); 323 324 /* 325 * The SOCK_PACKET socket receives _all_ frames. 326 */ 327 328 spkt->spkt_family = dev->type; 329 strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device)); 330 spkt->spkt_protocol = skb->protocol; 331 332 /* 333 * Charge the memory to the socket. This is done specifically 334 * to prevent sockets using all the memory up. 335 */ 336 337 if (sock_queue_rcv_skb(sk,skb) == 0) 338 return 0; 339 340 out: 341 kfree_skb(skb); 342 oom: 343 return 0; 344 } 345 346 347 /* 348 * Output a raw packet to a device layer. This bypasses all the other 349 * protocol layers and you must therefore supply it with a complete frame 350 */ 351 352 static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock, 353 struct msghdr *msg, size_t len) 354 { 355 struct sock *sk = sock->sk; 356 struct sockaddr_pkt *saddr=(struct sockaddr_pkt *)msg->msg_name; 357 struct sk_buff *skb; 358 struct net_device *dev; 359 __be16 proto=0; 360 int err; 361 362 /* 363 * Get and verify the address. 364 */ 365 366 if (saddr) 367 { 368 if (msg->msg_namelen < sizeof(struct sockaddr)) 369 return(-EINVAL); 370 if (msg->msg_namelen==sizeof(struct sockaddr_pkt)) 371 proto=saddr->spkt_protocol; 372 } 373 else 374 return(-ENOTCONN); /* SOCK_PACKET must be sent giving an address */ 375 376 /* 377 * Find the device first to size check it 378 */ 379 380 saddr->spkt_device[13] = 0; 381 dev = dev_get_by_name(sock_net(sk), saddr->spkt_device); 382 err = -ENODEV; 383 if (dev == NULL) 384 goto out_unlock; 385 386 err = -ENETDOWN; 387 if (!(dev->flags & IFF_UP)) 388 goto out_unlock; 389 390 /* 391 * You may not queue a frame bigger than the mtu. This is the lowest level 392 * raw protocol and you must do your own fragmentation at this level. 393 */ 394 395 err = -EMSGSIZE; 396 if (len > dev->mtu + dev->hard_header_len) 397 goto out_unlock; 398 399 err = -ENOBUFS; 400 skb = sock_wmalloc(sk, len + LL_RESERVED_SPACE(dev), 0, GFP_KERNEL); 401 402 /* 403 * If the write buffer is full, then tough. At this level the user gets to 404 * deal with the problem - do your own algorithmic backoffs. That's far 405 * more flexible. 406 */ 407 408 if (skb == NULL) 409 goto out_unlock; 410 411 /* 412 * Fill it in 413 */ 414 415 /* FIXME: Save some space for broken drivers that write a 416 * hard header at transmission time by themselves. PPP is the 417 * notable one here. This should really be fixed at the driver level. 418 */ 419 skb_reserve(skb, LL_RESERVED_SPACE(dev)); 420 skb_reset_network_header(skb); 421 422 /* Try to align data part correctly */ 423 if (dev->header_ops) { 424 skb->data -= dev->hard_header_len; 425 skb->tail -= dev->hard_header_len; 426 if (len < dev->hard_header_len) 427 skb_reset_network_header(skb); 428 } 429 430 /* Returns -EFAULT on error */ 431 err = memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len); 432 skb->protocol = proto; 433 skb->dev = dev; 434 skb->priority = sk->sk_priority; 435 if (err) 436 goto out_free; 437 438 /* 439 * Now send it 440 */ 441 442 dev_queue_xmit(skb); 443 dev_put(dev); 444 return(len); 445 446 out_free: 447 kfree_skb(skb); 448 out_unlock: 449 if (dev) 450 dev_put(dev); 451 return err; 452 } 453 454 static inline unsigned int run_filter(struct sk_buff *skb, struct sock *sk, 455 unsigned int res) 456 { 457 struct sk_filter *filter; 458 459 rcu_read_lock_bh(); 460 filter = rcu_dereference(sk->sk_filter); 461 if (filter != NULL) 462 res = sk_run_filter(skb, filter->insns, filter->len); 463 rcu_read_unlock_bh(); 464 465 return res; 466 } 467 468 /* 469 This function makes lazy skb cloning in hope that most of packets 470 are discarded by BPF. 471 472 Note tricky part: we DO mangle shared skb! skb->data, skb->len 473 and skb->cb are mangled. It works because (and until) packets 474 falling here are owned by current CPU. Output packets are cloned 475 by dev_queue_xmit_nit(), input packets are processed by net_bh 476 sequencially, so that if we return skb to original state on exit, 477 we will not harm anyone. 478 */ 479 480 static int packet_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) 481 { 482 struct sock *sk; 483 struct sockaddr_ll *sll; 484 struct packet_sock *po; 485 u8 * skb_head = skb->data; 486 int skb_len = skb->len; 487 unsigned int snaplen, res; 488 489 if (skb->pkt_type == PACKET_LOOPBACK) 490 goto drop; 491 492 sk = pt->af_packet_priv; 493 po = pkt_sk(sk); 494 495 if (dev_net(dev) != sock_net(sk)) 496 goto drop; 497 498 skb->dev = dev; 499 500 if (dev->header_ops) { 501 /* The device has an explicit notion of ll header, 502 exported to higher levels. 503 504 Otherwise, the device hides datails of it frame 505 structure, so that corresponding packet head 506 never delivered to user. 507 */ 508 if (sk->sk_type != SOCK_DGRAM) 509 skb_push(skb, skb->data - skb_mac_header(skb)); 510 else if (skb->pkt_type == PACKET_OUTGOING) { 511 /* Special case: outgoing packets have ll header at head */ 512 skb_pull(skb, skb_network_offset(skb)); 513 } 514 } 515 516 snaplen = skb->len; 517 518 res = run_filter(skb, sk, snaplen); 519 if (!res) 520 goto drop_n_restore; 521 if (snaplen > res) 522 snaplen = res; 523 524 if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >= 525 (unsigned)sk->sk_rcvbuf) 526 goto drop_n_acct; 527 528 if (skb_shared(skb)) { 529 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC); 530 if (nskb == NULL) 531 goto drop_n_acct; 532 533 if (skb_head != skb->data) { 534 skb->data = skb_head; 535 skb->len = skb_len; 536 } 537 kfree_skb(skb); 538 skb = nskb; 539 } 540 541 BUILD_BUG_ON(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8 > 542 sizeof(skb->cb)); 543 544 sll = &PACKET_SKB_CB(skb)->sa.ll; 545 sll->sll_family = AF_PACKET; 546 sll->sll_hatype = dev->type; 547 sll->sll_protocol = skb->protocol; 548 sll->sll_pkttype = skb->pkt_type; 549 if (unlikely(po->origdev)) 550 sll->sll_ifindex = orig_dev->ifindex; 551 else 552 sll->sll_ifindex = dev->ifindex; 553 554 sll->sll_halen = dev_parse_header(skb, sll->sll_addr); 555 556 PACKET_SKB_CB(skb)->origlen = skb->len; 557 558 if (pskb_trim(skb, snaplen)) 559 goto drop_n_acct; 560 561 skb_set_owner_r(skb, sk); 562 skb->dev = NULL; 563 dst_release(skb->dst); 564 skb->dst = NULL; 565 566 /* drop conntrack reference */ 567 nf_reset(skb); 568 569 spin_lock(&sk->sk_receive_queue.lock); 570 po->stats.tp_packets++; 571 __skb_queue_tail(&sk->sk_receive_queue, skb); 572 spin_unlock(&sk->sk_receive_queue.lock); 573 sk->sk_data_ready(sk, skb->len); 574 return 0; 575 576 drop_n_acct: 577 spin_lock(&sk->sk_receive_queue.lock); 578 po->stats.tp_drops++; 579 spin_unlock(&sk->sk_receive_queue.lock); 580 581 drop_n_restore: 582 if (skb_head != skb->data && skb_shared(skb)) { 583 skb->data = skb_head; 584 skb->len = skb_len; 585 } 586 drop: 587 consume_skb(skb); 588 return 0; 589 } 590 591 #ifdef CONFIG_PACKET_MMAP 592 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) 593 { 594 struct sock *sk; 595 struct packet_sock *po; 596 struct sockaddr_ll *sll; 597 union { 598 struct tpacket_hdr *h1; 599 struct tpacket2_hdr *h2; 600 void *raw; 601 } h; 602 u8 * skb_head = skb->data; 603 int skb_len = skb->len; 604 unsigned int snaplen, res; 605 unsigned long status = TP_STATUS_LOSING|TP_STATUS_USER; 606 unsigned short macoff, netoff, hdrlen; 607 struct sk_buff *copy_skb = NULL; 608 struct timeval tv; 609 struct timespec ts; 610 611 if (skb->pkt_type == PACKET_LOOPBACK) 612 goto drop; 613 614 sk = pt->af_packet_priv; 615 po = pkt_sk(sk); 616 617 if (dev_net(dev) != sock_net(sk)) 618 goto drop; 619 620 if (dev->header_ops) { 621 if (sk->sk_type != SOCK_DGRAM) 622 skb_push(skb, skb->data - skb_mac_header(skb)); 623 else if (skb->pkt_type == PACKET_OUTGOING) { 624 /* Special case: outgoing packets have ll header at head */ 625 skb_pull(skb, skb_network_offset(skb)); 626 } 627 } 628 629 if (skb->ip_summed == CHECKSUM_PARTIAL) 630 status |= TP_STATUS_CSUMNOTREADY; 631 632 snaplen = skb->len; 633 634 res = run_filter(skb, sk, snaplen); 635 if (!res) 636 goto drop_n_restore; 637 if (snaplen > res) 638 snaplen = res; 639 640 if (sk->sk_type == SOCK_DGRAM) { 641 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 + 642 po->tp_reserve; 643 } else { 644 unsigned maclen = skb_network_offset(skb); 645 netoff = TPACKET_ALIGN(po->tp_hdrlen + 646 (maclen < 16 ? 16 : maclen)) + 647 po->tp_reserve; 648 macoff = netoff - maclen; 649 } 650 651 if (macoff + snaplen > po->frame_size) { 652 if (po->copy_thresh && 653 atomic_read(&sk->sk_rmem_alloc) + skb->truesize < 654 (unsigned)sk->sk_rcvbuf) { 655 if (skb_shared(skb)) { 656 copy_skb = skb_clone(skb, GFP_ATOMIC); 657 } else { 658 copy_skb = skb_get(skb); 659 skb_head = skb->data; 660 } 661 if (copy_skb) 662 skb_set_owner_r(copy_skb, sk); 663 } 664 snaplen = po->frame_size - macoff; 665 if ((int)snaplen < 0) 666 snaplen = 0; 667 } 668 669 spin_lock(&sk->sk_receive_queue.lock); 670 h.raw = packet_lookup_frame(po, po->head, TP_STATUS_KERNEL); 671 if (!h.raw) 672 goto ring_is_full; 673 po->head = po->head != po->frame_max ? po->head+1 : 0; 674 po->stats.tp_packets++; 675 if (copy_skb) { 676 status |= TP_STATUS_COPY; 677 __skb_queue_tail(&sk->sk_receive_queue, copy_skb); 678 } 679 if (!po->stats.tp_drops) 680 status &= ~TP_STATUS_LOSING; 681 spin_unlock(&sk->sk_receive_queue.lock); 682 683 skb_copy_bits(skb, 0, h.raw + macoff, snaplen); 684 685 switch (po->tp_version) { 686 case TPACKET_V1: 687 h.h1->tp_len = skb->len; 688 h.h1->tp_snaplen = snaplen; 689 h.h1->tp_mac = macoff; 690 h.h1->tp_net = netoff; 691 if (skb->tstamp.tv64) 692 tv = ktime_to_timeval(skb->tstamp); 693 else 694 do_gettimeofday(&tv); 695 h.h1->tp_sec = tv.tv_sec; 696 h.h1->tp_usec = tv.tv_usec; 697 hdrlen = sizeof(*h.h1); 698 break; 699 case TPACKET_V2: 700 h.h2->tp_len = skb->len; 701 h.h2->tp_snaplen = snaplen; 702 h.h2->tp_mac = macoff; 703 h.h2->tp_net = netoff; 704 if (skb->tstamp.tv64) 705 ts = ktime_to_timespec(skb->tstamp); 706 else 707 getnstimeofday(&ts); 708 h.h2->tp_sec = ts.tv_sec; 709 h.h2->tp_nsec = ts.tv_nsec; 710 h.h2->tp_vlan_tci = skb->vlan_tci; 711 hdrlen = sizeof(*h.h2); 712 break; 713 default: 714 BUG(); 715 } 716 717 sll = h.raw + TPACKET_ALIGN(hdrlen); 718 sll->sll_halen = dev_parse_header(skb, sll->sll_addr); 719 sll->sll_family = AF_PACKET; 720 sll->sll_hatype = dev->type; 721 sll->sll_protocol = skb->protocol; 722 sll->sll_pkttype = skb->pkt_type; 723 if (unlikely(po->origdev)) 724 sll->sll_ifindex = orig_dev->ifindex; 725 else 726 sll->sll_ifindex = dev->ifindex; 727 728 __packet_set_status(po, h.raw, status); 729 smp_mb(); 730 731 { 732 struct page *p_start, *p_end; 733 u8 *h_end = h.raw + macoff + snaplen - 1; 734 735 p_start = virt_to_page(h.raw); 736 p_end = virt_to_page(h_end); 737 while (p_start <= p_end) { 738 flush_dcache_page(p_start); 739 p_start++; 740 } 741 } 742 743 sk->sk_data_ready(sk, 0); 744 745 drop_n_restore: 746 if (skb_head != skb->data && skb_shared(skb)) { 747 skb->data = skb_head; 748 skb->len = skb_len; 749 } 750 drop: 751 kfree_skb(skb); 752 return 0; 753 754 ring_is_full: 755 po->stats.tp_drops++; 756 spin_unlock(&sk->sk_receive_queue.lock); 757 758 sk->sk_data_ready(sk, 0); 759 kfree_skb(copy_skb); 760 goto drop_n_restore; 761 } 762 763 #endif 764 765 766 static int packet_sendmsg(struct kiocb *iocb, struct socket *sock, 767 struct msghdr *msg, size_t len) 768 { 769 struct sock *sk = sock->sk; 770 struct sockaddr_ll *saddr=(struct sockaddr_ll *)msg->msg_name; 771 struct sk_buff *skb; 772 struct net_device *dev; 773 __be16 proto; 774 unsigned char *addr; 775 int ifindex, err, reserve = 0; 776 777 /* 778 * Get and verify the address. 779 */ 780 781 if (saddr == NULL) { 782 struct packet_sock *po = pkt_sk(sk); 783 784 ifindex = po->ifindex; 785 proto = po->num; 786 addr = NULL; 787 } else { 788 err = -EINVAL; 789 if (msg->msg_namelen < sizeof(struct sockaddr_ll)) 790 goto out; 791 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr))) 792 goto out; 793 ifindex = saddr->sll_ifindex; 794 proto = saddr->sll_protocol; 795 addr = saddr->sll_addr; 796 } 797 798 799 dev = dev_get_by_index(sock_net(sk), ifindex); 800 err = -ENXIO; 801 if (dev == NULL) 802 goto out_unlock; 803 if (sock->type == SOCK_RAW) 804 reserve = dev->hard_header_len; 805 806 err = -ENETDOWN; 807 if (!(dev->flags & IFF_UP)) 808 goto out_unlock; 809 810 err = -EMSGSIZE; 811 if (len > dev->mtu+reserve) 812 goto out_unlock; 813 814 skb = sock_alloc_send_skb(sk, len + LL_ALLOCATED_SPACE(dev), 815 msg->msg_flags & MSG_DONTWAIT, &err); 816 if (skb==NULL) 817 goto out_unlock; 818 819 skb_reserve(skb, LL_RESERVED_SPACE(dev)); 820 skb_reset_network_header(skb); 821 822 err = -EINVAL; 823 if (sock->type == SOCK_DGRAM && 824 dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len) < 0) 825 goto out_free; 826 827 /* Returns -EFAULT on error */ 828 err = memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len); 829 if (err) 830 goto out_free; 831 832 skb->protocol = proto; 833 skb->dev = dev; 834 skb->priority = sk->sk_priority; 835 836 /* 837 * Now send it 838 */ 839 840 err = dev_queue_xmit(skb); 841 if (err > 0 && (err = net_xmit_errno(err)) != 0) 842 goto out_unlock; 843 844 dev_put(dev); 845 846 return(len); 847 848 out_free: 849 kfree_skb(skb); 850 out_unlock: 851 if (dev) 852 dev_put(dev); 853 out: 854 return err; 855 } 856 857 /* 858 * Close a PACKET socket. This is fairly simple. We immediately go 859 * to 'closed' state and remove our protocol entry in the device list. 860 */ 861 862 static int packet_release(struct socket *sock) 863 { 864 struct sock *sk = sock->sk; 865 struct packet_sock *po; 866 struct net *net; 867 868 if (!sk) 869 return 0; 870 871 net = sock_net(sk); 872 po = pkt_sk(sk); 873 874 write_lock_bh(&net->packet.sklist_lock); 875 sk_del_node_init(sk); 876 sock_prot_inuse_add(net, sk->sk_prot, -1); 877 write_unlock_bh(&net->packet.sklist_lock); 878 879 /* 880 * Unhook packet receive handler. 881 */ 882 883 if (po->running) { 884 /* 885 * Remove the protocol hook 886 */ 887 dev_remove_pack(&po->prot_hook); 888 po->running = 0; 889 po->num = 0; 890 __sock_put(sk); 891 } 892 893 packet_flush_mclist(sk); 894 895 #ifdef CONFIG_PACKET_MMAP 896 if (po->pg_vec) { 897 struct tpacket_req req; 898 memset(&req, 0, sizeof(req)); 899 packet_set_ring(sk, &req, 1); 900 } 901 #endif 902 903 /* 904 * Now the socket is dead. No more input will appear. 905 */ 906 907 sock_orphan(sk); 908 sock->sk = NULL; 909 910 /* Purge queues */ 911 912 skb_queue_purge(&sk->sk_receive_queue); 913 sk_refcnt_debug_release(sk); 914 915 sock_put(sk); 916 return 0; 917 } 918 919 /* 920 * Attach a packet hook. 921 */ 922 923 static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol) 924 { 925 struct packet_sock *po = pkt_sk(sk); 926 /* 927 * Detach an existing hook if present. 928 */ 929 930 lock_sock(sk); 931 932 spin_lock(&po->bind_lock); 933 if (po->running) { 934 __sock_put(sk); 935 po->running = 0; 936 po->num = 0; 937 spin_unlock(&po->bind_lock); 938 dev_remove_pack(&po->prot_hook); 939 spin_lock(&po->bind_lock); 940 } 941 942 po->num = protocol; 943 po->prot_hook.type = protocol; 944 po->prot_hook.dev = dev; 945 946 po->ifindex = dev ? dev->ifindex : 0; 947 948 if (protocol == 0) 949 goto out_unlock; 950 951 if (!dev || (dev->flags & IFF_UP)) { 952 dev_add_pack(&po->prot_hook); 953 sock_hold(sk); 954 po->running = 1; 955 } else { 956 sk->sk_err = ENETDOWN; 957 if (!sock_flag(sk, SOCK_DEAD)) 958 sk->sk_error_report(sk); 959 } 960 961 out_unlock: 962 spin_unlock(&po->bind_lock); 963 release_sock(sk); 964 return 0; 965 } 966 967 /* 968 * Bind a packet socket to a device 969 */ 970 971 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr, int addr_len) 972 { 973 struct sock *sk=sock->sk; 974 char name[15]; 975 struct net_device *dev; 976 int err = -ENODEV; 977 978 /* 979 * Check legality 980 */ 981 982 if (addr_len != sizeof(struct sockaddr)) 983 return -EINVAL; 984 strlcpy(name,uaddr->sa_data,sizeof(name)); 985 986 dev = dev_get_by_name(sock_net(sk), name); 987 if (dev) { 988 err = packet_do_bind(sk, dev, pkt_sk(sk)->num); 989 dev_put(dev); 990 } 991 return err; 992 } 993 994 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) 995 { 996 struct sockaddr_ll *sll = (struct sockaddr_ll*)uaddr; 997 struct sock *sk=sock->sk; 998 struct net_device *dev = NULL; 999 int err; 1000 1001 1002 /* 1003 * Check legality 1004 */ 1005 1006 if (addr_len < sizeof(struct sockaddr_ll)) 1007 return -EINVAL; 1008 if (sll->sll_family != AF_PACKET) 1009 return -EINVAL; 1010 1011 if (sll->sll_ifindex) { 1012 err = -ENODEV; 1013 dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex); 1014 if (dev == NULL) 1015 goto out; 1016 } 1017 err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num); 1018 if (dev) 1019 dev_put(dev); 1020 1021 out: 1022 return err; 1023 } 1024 1025 static struct proto packet_proto = { 1026 .name = "PACKET", 1027 .owner = THIS_MODULE, 1028 .obj_size = sizeof(struct packet_sock), 1029 }; 1030 1031 /* 1032 * Create a packet of type SOCK_PACKET. 1033 */ 1034 1035 static int packet_create(struct net *net, struct socket *sock, int protocol) 1036 { 1037 struct sock *sk; 1038 struct packet_sock *po; 1039 __be16 proto = (__force __be16)protocol; /* weird, but documented */ 1040 int err; 1041 1042 if (!capable(CAP_NET_RAW)) 1043 return -EPERM; 1044 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW && 1045 sock->type != SOCK_PACKET) 1046 return -ESOCKTNOSUPPORT; 1047 1048 sock->state = SS_UNCONNECTED; 1049 1050 err = -ENOBUFS; 1051 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto); 1052 if (sk == NULL) 1053 goto out; 1054 1055 sock->ops = &packet_ops; 1056 if (sock->type == SOCK_PACKET) 1057 sock->ops = &packet_ops_spkt; 1058 1059 sock_init_data(sock, sk); 1060 1061 po = pkt_sk(sk); 1062 sk->sk_family = PF_PACKET; 1063 po->num = proto; 1064 1065 sk->sk_destruct = packet_sock_destruct; 1066 sk_refcnt_debug_inc(sk); 1067 1068 /* 1069 * Attach a protocol block 1070 */ 1071 1072 spin_lock_init(&po->bind_lock); 1073 mutex_init(&po->pg_vec_lock); 1074 po->prot_hook.func = packet_rcv; 1075 1076 if (sock->type == SOCK_PACKET) 1077 po->prot_hook.func = packet_rcv_spkt; 1078 1079 po->prot_hook.af_packet_priv = sk; 1080 1081 if (proto) { 1082 po->prot_hook.type = proto; 1083 dev_add_pack(&po->prot_hook); 1084 sock_hold(sk); 1085 po->running = 1; 1086 } 1087 1088 write_lock_bh(&net->packet.sklist_lock); 1089 sk_add_node(sk, &net->packet.sklist); 1090 sock_prot_inuse_add(net, &packet_proto, 1); 1091 write_unlock_bh(&net->packet.sklist_lock); 1092 return(0); 1093 out: 1094 return err; 1095 } 1096 1097 /* 1098 * Pull a packet from our receive queue and hand it to the user. 1099 * If necessary we block. 1100 */ 1101 1102 static int packet_recvmsg(struct kiocb *iocb, struct socket *sock, 1103 struct msghdr *msg, size_t len, int flags) 1104 { 1105 struct sock *sk = sock->sk; 1106 struct sk_buff *skb; 1107 int copied, err; 1108 struct sockaddr_ll *sll; 1109 1110 err = -EINVAL; 1111 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT)) 1112 goto out; 1113 1114 #if 0 1115 /* What error should we return now? EUNATTACH? */ 1116 if (pkt_sk(sk)->ifindex < 0) 1117 return -ENODEV; 1118 #endif 1119 1120 /* 1121 * Call the generic datagram receiver. This handles all sorts 1122 * of horrible races and re-entrancy so we can forget about it 1123 * in the protocol layers. 1124 * 1125 * Now it will return ENETDOWN, if device have just gone down, 1126 * but then it will block. 1127 */ 1128 1129 skb=skb_recv_datagram(sk,flags,flags&MSG_DONTWAIT,&err); 1130 1131 /* 1132 * An error occurred so return it. Because skb_recv_datagram() 1133 * handles the blocking we don't see and worry about blocking 1134 * retries. 1135 */ 1136 1137 if (skb == NULL) 1138 goto out; 1139 1140 /* 1141 * If the address length field is there to be filled in, we fill 1142 * it in now. 1143 */ 1144 1145 sll = &PACKET_SKB_CB(skb)->sa.ll; 1146 if (sock->type == SOCK_PACKET) 1147 msg->msg_namelen = sizeof(struct sockaddr_pkt); 1148 else 1149 msg->msg_namelen = sll->sll_halen + offsetof(struct sockaddr_ll, sll_addr); 1150 1151 /* 1152 * You lose any data beyond the buffer you gave. If it worries a 1153 * user program they can ask the device for its MTU anyway. 1154 */ 1155 1156 copied = skb->len; 1157 if (copied > len) 1158 { 1159 copied=len; 1160 msg->msg_flags|=MSG_TRUNC; 1161 } 1162 1163 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); 1164 if (err) 1165 goto out_free; 1166 1167 sock_recv_timestamp(msg, sk, skb); 1168 1169 if (msg->msg_name) 1170 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa, 1171 msg->msg_namelen); 1172 1173 if (pkt_sk(sk)->auxdata) { 1174 struct tpacket_auxdata aux; 1175 1176 aux.tp_status = TP_STATUS_USER; 1177 if (skb->ip_summed == CHECKSUM_PARTIAL) 1178 aux.tp_status |= TP_STATUS_CSUMNOTREADY; 1179 aux.tp_len = PACKET_SKB_CB(skb)->origlen; 1180 aux.tp_snaplen = skb->len; 1181 aux.tp_mac = 0; 1182 aux.tp_net = skb_network_offset(skb); 1183 aux.tp_vlan_tci = skb->vlan_tci; 1184 1185 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux); 1186 } 1187 1188 /* 1189 * Free or return the buffer as appropriate. Again this 1190 * hides all the races and re-entrancy issues from us. 1191 */ 1192 err = (flags&MSG_TRUNC) ? skb->len : copied; 1193 1194 out_free: 1195 skb_free_datagram(sk, skb); 1196 out: 1197 return err; 1198 } 1199 1200 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr, 1201 int *uaddr_len, int peer) 1202 { 1203 struct net_device *dev; 1204 struct sock *sk = sock->sk; 1205 1206 if (peer) 1207 return -EOPNOTSUPP; 1208 1209 uaddr->sa_family = AF_PACKET; 1210 dev = dev_get_by_index(sock_net(sk), pkt_sk(sk)->ifindex); 1211 if (dev) { 1212 strlcpy(uaddr->sa_data, dev->name, 15); 1213 dev_put(dev); 1214 } else 1215 memset(uaddr->sa_data, 0, 14); 1216 *uaddr_len = sizeof(*uaddr); 1217 1218 return 0; 1219 } 1220 1221 static int packet_getname(struct socket *sock, struct sockaddr *uaddr, 1222 int *uaddr_len, int peer) 1223 { 1224 struct net_device *dev; 1225 struct sock *sk = sock->sk; 1226 struct packet_sock *po = pkt_sk(sk); 1227 struct sockaddr_ll *sll = (struct sockaddr_ll*)uaddr; 1228 1229 if (peer) 1230 return -EOPNOTSUPP; 1231 1232 sll->sll_family = AF_PACKET; 1233 sll->sll_ifindex = po->ifindex; 1234 sll->sll_protocol = po->num; 1235 dev = dev_get_by_index(sock_net(sk), po->ifindex); 1236 if (dev) { 1237 sll->sll_hatype = dev->type; 1238 sll->sll_halen = dev->addr_len; 1239 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len); 1240 dev_put(dev); 1241 } else { 1242 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */ 1243 sll->sll_halen = 0; 1244 } 1245 *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen; 1246 1247 return 0; 1248 } 1249 1250 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i, 1251 int what) 1252 { 1253 switch (i->type) { 1254 case PACKET_MR_MULTICAST: 1255 if (what > 0) 1256 dev_mc_add(dev, i->addr, i->alen, 0); 1257 else 1258 dev_mc_delete(dev, i->addr, i->alen, 0); 1259 break; 1260 case PACKET_MR_PROMISC: 1261 return dev_set_promiscuity(dev, what); 1262 break; 1263 case PACKET_MR_ALLMULTI: 1264 return dev_set_allmulti(dev, what); 1265 break; 1266 default:; 1267 } 1268 return 0; 1269 } 1270 1271 static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what) 1272 { 1273 for ( ; i; i=i->next) { 1274 if (i->ifindex == dev->ifindex) 1275 packet_dev_mc(dev, i, what); 1276 } 1277 } 1278 1279 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq) 1280 { 1281 struct packet_sock *po = pkt_sk(sk); 1282 struct packet_mclist *ml, *i; 1283 struct net_device *dev; 1284 int err; 1285 1286 rtnl_lock(); 1287 1288 err = -ENODEV; 1289 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex); 1290 if (!dev) 1291 goto done; 1292 1293 err = -EINVAL; 1294 if (mreq->mr_alen > dev->addr_len) 1295 goto done; 1296 1297 err = -ENOBUFS; 1298 i = kmalloc(sizeof(*i), GFP_KERNEL); 1299 if (i == NULL) 1300 goto done; 1301 1302 err = 0; 1303 for (ml = po->mclist; ml; ml = ml->next) { 1304 if (ml->ifindex == mreq->mr_ifindex && 1305 ml->type == mreq->mr_type && 1306 ml->alen == mreq->mr_alen && 1307 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) { 1308 ml->count++; 1309 /* Free the new element ... */ 1310 kfree(i); 1311 goto done; 1312 } 1313 } 1314 1315 i->type = mreq->mr_type; 1316 i->ifindex = mreq->mr_ifindex; 1317 i->alen = mreq->mr_alen; 1318 memcpy(i->addr, mreq->mr_address, i->alen); 1319 i->count = 1; 1320 i->next = po->mclist; 1321 po->mclist = i; 1322 err = packet_dev_mc(dev, i, 1); 1323 if (err) { 1324 po->mclist = i->next; 1325 kfree(i); 1326 } 1327 1328 done: 1329 rtnl_unlock(); 1330 return err; 1331 } 1332 1333 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq) 1334 { 1335 struct packet_mclist *ml, **mlp; 1336 1337 rtnl_lock(); 1338 1339 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) { 1340 if (ml->ifindex == mreq->mr_ifindex && 1341 ml->type == mreq->mr_type && 1342 ml->alen == mreq->mr_alen && 1343 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) { 1344 if (--ml->count == 0) { 1345 struct net_device *dev; 1346 *mlp = ml->next; 1347 dev = dev_get_by_index(sock_net(sk), ml->ifindex); 1348 if (dev) { 1349 packet_dev_mc(dev, ml, -1); 1350 dev_put(dev); 1351 } 1352 kfree(ml); 1353 } 1354 rtnl_unlock(); 1355 return 0; 1356 } 1357 } 1358 rtnl_unlock(); 1359 return -EADDRNOTAVAIL; 1360 } 1361 1362 static void packet_flush_mclist(struct sock *sk) 1363 { 1364 struct packet_sock *po = pkt_sk(sk); 1365 struct packet_mclist *ml; 1366 1367 if (!po->mclist) 1368 return; 1369 1370 rtnl_lock(); 1371 while ((ml = po->mclist) != NULL) { 1372 struct net_device *dev; 1373 1374 po->mclist = ml->next; 1375 if ((dev = dev_get_by_index(sock_net(sk), ml->ifindex)) != NULL) { 1376 packet_dev_mc(dev, ml, -1); 1377 dev_put(dev); 1378 } 1379 kfree(ml); 1380 } 1381 rtnl_unlock(); 1382 } 1383 1384 static int 1385 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, int optlen) 1386 { 1387 struct sock *sk = sock->sk; 1388 struct packet_sock *po = pkt_sk(sk); 1389 int ret; 1390 1391 if (level != SOL_PACKET) 1392 return -ENOPROTOOPT; 1393 1394 switch(optname) { 1395 case PACKET_ADD_MEMBERSHIP: 1396 case PACKET_DROP_MEMBERSHIP: 1397 { 1398 struct packet_mreq_max mreq; 1399 int len = optlen; 1400 memset(&mreq, 0, sizeof(mreq)); 1401 if (len < sizeof(struct packet_mreq)) 1402 return -EINVAL; 1403 if (len > sizeof(mreq)) 1404 len = sizeof(mreq); 1405 if (copy_from_user(&mreq,optval,len)) 1406 return -EFAULT; 1407 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address))) 1408 return -EINVAL; 1409 if (optname == PACKET_ADD_MEMBERSHIP) 1410 ret = packet_mc_add(sk, &mreq); 1411 else 1412 ret = packet_mc_drop(sk, &mreq); 1413 return ret; 1414 } 1415 1416 #ifdef CONFIG_PACKET_MMAP 1417 case PACKET_RX_RING: 1418 { 1419 struct tpacket_req req; 1420 1421 if (optlen<sizeof(req)) 1422 return -EINVAL; 1423 if (copy_from_user(&req,optval,sizeof(req))) 1424 return -EFAULT; 1425 return packet_set_ring(sk, &req, 0); 1426 } 1427 case PACKET_COPY_THRESH: 1428 { 1429 int val; 1430 1431 if (optlen!=sizeof(val)) 1432 return -EINVAL; 1433 if (copy_from_user(&val,optval,sizeof(val))) 1434 return -EFAULT; 1435 1436 pkt_sk(sk)->copy_thresh = val; 1437 return 0; 1438 } 1439 case PACKET_VERSION: 1440 { 1441 int val; 1442 1443 if (optlen != sizeof(val)) 1444 return -EINVAL; 1445 if (po->pg_vec) 1446 return -EBUSY; 1447 if (copy_from_user(&val, optval, sizeof(val))) 1448 return -EFAULT; 1449 switch (val) { 1450 case TPACKET_V1: 1451 case TPACKET_V2: 1452 po->tp_version = val; 1453 return 0; 1454 default: 1455 return -EINVAL; 1456 } 1457 } 1458 case PACKET_RESERVE: 1459 { 1460 unsigned int val; 1461 1462 if (optlen != sizeof(val)) 1463 return -EINVAL; 1464 if (po->pg_vec) 1465 return -EBUSY; 1466 if (copy_from_user(&val, optval, sizeof(val))) 1467 return -EFAULT; 1468 po->tp_reserve = val; 1469 return 0; 1470 } 1471 #endif 1472 case PACKET_AUXDATA: 1473 { 1474 int val; 1475 1476 if (optlen < sizeof(val)) 1477 return -EINVAL; 1478 if (copy_from_user(&val, optval, sizeof(val))) 1479 return -EFAULT; 1480 1481 po->auxdata = !!val; 1482 return 0; 1483 } 1484 case PACKET_ORIGDEV: 1485 { 1486 int val; 1487 1488 if (optlen < sizeof(val)) 1489 return -EINVAL; 1490 if (copy_from_user(&val, optval, sizeof(val))) 1491 return -EFAULT; 1492 1493 po->origdev = !!val; 1494 return 0; 1495 } 1496 default: 1497 return -ENOPROTOOPT; 1498 } 1499 } 1500 1501 static int packet_getsockopt(struct socket *sock, int level, int optname, 1502 char __user *optval, int __user *optlen) 1503 { 1504 int len; 1505 int val; 1506 struct sock *sk = sock->sk; 1507 struct packet_sock *po = pkt_sk(sk); 1508 void *data; 1509 struct tpacket_stats st; 1510 1511 if (level != SOL_PACKET) 1512 return -ENOPROTOOPT; 1513 1514 if (get_user(len, optlen)) 1515 return -EFAULT; 1516 1517 if (len < 0) 1518 return -EINVAL; 1519 1520 switch(optname) { 1521 case PACKET_STATISTICS: 1522 if (len > sizeof(struct tpacket_stats)) 1523 len = sizeof(struct tpacket_stats); 1524 spin_lock_bh(&sk->sk_receive_queue.lock); 1525 st = po->stats; 1526 memset(&po->stats, 0, sizeof(st)); 1527 spin_unlock_bh(&sk->sk_receive_queue.lock); 1528 st.tp_packets += st.tp_drops; 1529 1530 data = &st; 1531 break; 1532 case PACKET_AUXDATA: 1533 if (len > sizeof(int)) 1534 len = sizeof(int); 1535 val = po->auxdata; 1536 1537 data = &val; 1538 break; 1539 case PACKET_ORIGDEV: 1540 if (len > sizeof(int)) 1541 len = sizeof(int); 1542 val = po->origdev; 1543 1544 data = &val; 1545 break; 1546 #ifdef CONFIG_PACKET_MMAP 1547 case PACKET_VERSION: 1548 if (len > sizeof(int)) 1549 len = sizeof(int); 1550 val = po->tp_version; 1551 data = &val; 1552 break; 1553 case PACKET_HDRLEN: 1554 if (len > sizeof(int)) 1555 len = sizeof(int); 1556 if (copy_from_user(&val, optval, len)) 1557 return -EFAULT; 1558 switch (val) { 1559 case TPACKET_V1: 1560 val = sizeof(struct tpacket_hdr); 1561 break; 1562 case TPACKET_V2: 1563 val = sizeof(struct tpacket2_hdr); 1564 break; 1565 default: 1566 return -EINVAL; 1567 } 1568 data = &val; 1569 break; 1570 case PACKET_RESERVE: 1571 if (len > sizeof(unsigned int)) 1572 len = sizeof(unsigned int); 1573 val = po->tp_reserve; 1574 data = &val; 1575 break; 1576 #endif 1577 default: 1578 return -ENOPROTOOPT; 1579 } 1580 1581 if (put_user(len, optlen)) 1582 return -EFAULT; 1583 if (copy_to_user(optval, data, len)) 1584 return -EFAULT; 1585 return 0; 1586 } 1587 1588 1589 static int packet_notifier(struct notifier_block *this, unsigned long msg, void *data) 1590 { 1591 struct sock *sk; 1592 struct hlist_node *node; 1593 struct net_device *dev = data; 1594 struct net *net = dev_net(dev); 1595 1596 read_lock(&net->packet.sklist_lock); 1597 sk_for_each(sk, node, &net->packet.sklist) { 1598 struct packet_sock *po = pkt_sk(sk); 1599 1600 switch (msg) { 1601 case NETDEV_UNREGISTER: 1602 if (po->mclist) 1603 packet_dev_mclist(dev, po->mclist, -1); 1604 /* fallthrough */ 1605 1606 case NETDEV_DOWN: 1607 if (dev->ifindex == po->ifindex) { 1608 spin_lock(&po->bind_lock); 1609 if (po->running) { 1610 __dev_remove_pack(&po->prot_hook); 1611 __sock_put(sk); 1612 po->running = 0; 1613 sk->sk_err = ENETDOWN; 1614 if (!sock_flag(sk, SOCK_DEAD)) 1615 sk->sk_error_report(sk); 1616 } 1617 if (msg == NETDEV_UNREGISTER) { 1618 po->ifindex = -1; 1619 po->prot_hook.dev = NULL; 1620 } 1621 spin_unlock(&po->bind_lock); 1622 } 1623 break; 1624 case NETDEV_UP: 1625 spin_lock(&po->bind_lock); 1626 if (dev->ifindex == po->ifindex && po->num && 1627 !po->running) { 1628 dev_add_pack(&po->prot_hook); 1629 sock_hold(sk); 1630 po->running = 1; 1631 } 1632 spin_unlock(&po->bind_lock); 1633 break; 1634 } 1635 } 1636 read_unlock(&net->packet.sklist_lock); 1637 return NOTIFY_DONE; 1638 } 1639 1640 1641 static int packet_ioctl(struct socket *sock, unsigned int cmd, 1642 unsigned long arg) 1643 { 1644 struct sock *sk = sock->sk; 1645 1646 switch(cmd) { 1647 case SIOCOUTQ: 1648 { 1649 int amount = atomic_read(&sk->sk_wmem_alloc); 1650 return put_user(amount, (int __user *)arg); 1651 } 1652 case SIOCINQ: 1653 { 1654 struct sk_buff *skb; 1655 int amount = 0; 1656 1657 spin_lock_bh(&sk->sk_receive_queue.lock); 1658 skb = skb_peek(&sk->sk_receive_queue); 1659 if (skb) 1660 amount = skb->len; 1661 spin_unlock_bh(&sk->sk_receive_queue.lock); 1662 return put_user(amount, (int __user *)arg); 1663 } 1664 case SIOCGSTAMP: 1665 return sock_get_timestamp(sk, (struct timeval __user *)arg); 1666 case SIOCGSTAMPNS: 1667 return sock_get_timestampns(sk, (struct timespec __user *)arg); 1668 1669 #ifdef CONFIG_INET 1670 case SIOCADDRT: 1671 case SIOCDELRT: 1672 case SIOCDARP: 1673 case SIOCGARP: 1674 case SIOCSARP: 1675 case SIOCGIFADDR: 1676 case SIOCSIFADDR: 1677 case SIOCGIFBRDADDR: 1678 case SIOCSIFBRDADDR: 1679 case SIOCGIFNETMASK: 1680 case SIOCSIFNETMASK: 1681 case SIOCGIFDSTADDR: 1682 case SIOCSIFDSTADDR: 1683 case SIOCSIFFLAGS: 1684 if (!net_eq(sock_net(sk), &init_net)) 1685 return -ENOIOCTLCMD; 1686 return inet_dgram_ops.ioctl(sock, cmd, arg); 1687 #endif 1688 1689 default: 1690 return -ENOIOCTLCMD; 1691 } 1692 return 0; 1693 } 1694 1695 #ifndef CONFIG_PACKET_MMAP 1696 #define packet_mmap sock_no_mmap 1697 #define packet_poll datagram_poll 1698 #else 1699 1700 static unsigned int packet_poll(struct file * file, struct socket *sock, 1701 poll_table *wait) 1702 { 1703 struct sock *sk = sock->sk; 1704 struct packet_sock *po = pkt_sk(sk); 1705 unsigned int mask = datagram_poll(file, sock, wait); 1706 1707 spin_lock_bh(&sk->sk_receive_queue.lock); 1708 if (po->pg_vec) { 1709 unsigned last = po->head ? po->head-1 : po->frame_max; 1710 1711 if (packet_lookup_frame(po, last, TP_STATUS_USER)) 1712 mask |= POLLIN | POLLRDNORM; 1713 } 1714 spin_unlock_bh(&sk->sk_receive_queue.lock); 1715 return mask; 1716 } 1717 1718 1719 /* Dirty? Well, I still did not learn better way to account 1720 * for user mmaps. 1721 */ 1722 1723 static void packet_mm_open(struct vm_area_struct *vma) 1724 { 1725 struct file *file = vma->vm_file; 1726 struct socket * sock = file->private_data; 1727 struct sock *sk = sock->sk; 1728 1729 if (sk) 1730 atomic_inc(&pkt_sk(sk)->mapped); 1731 } 1732 1733 static void packet_mm_close(struct vm_area_struct *vma) 1734 { 1735 struct file *file = vma->vm_file; 1736 struct socket * sock = file->private_data; 1737 struct sock *sk = sock->sk; 1738 1739 if (sk) 1740 atomic_dec(&pkt_sk(sk)->mapped); 1741 } 1742 1743 static struct vm_operations_struct packet_mmap_ops = { 1744 .open = packet_mm_open, 1745 .close =packet_mm_close, 1746 }; 1747 1748 static void free_pg_vec(char **pg_vec, unsigned int order, unsigned int len) 1749 { 1750 int i; 1751 1752 for (i = 0; i < len; i++) { 1753 if (likely(pg_vec[i])) 1754 free_pages((unsigned long) pg_vec[i], order); 1755 } 1756 kfree(pg_vec); 1757 } 1758 1759 static inline char *alloc_one_pg_vec_page(unsigned long order) 1760 { 1761 return (char *) __get_free_pages(GFP_KERNEL | __GFP_COMP | __GFP_ZERO, 1762 order); 1763 } 1764 1765 static char **alloc_pg_vec(struct tpacket_req *req, int order) 1766 { 1767 unsigned int block_nr = req->tp_block_nr; 1768 char **pg_vec; 1769 int i; 1770 1771 pg_vec = kzalloc(block_nr * sizeof(char *), GFP_KERNEL); 1772 if (unlikely(!pg_vec)) 1773 goto out; 1774 1775 for (i = 0; i < block_nr; i++) { 1776 pg_vec[i] = alloc_one_pg_vec_page(order); 1777 if (unlikely(!pg_vec[i])) 1778 goto out_free_pgvec; 1779 } 1780 1781 out: 1782 return pg_vec; 1783 1784 out_free_pgvec: 1785 free_pg_vec(pg_vec, order, block_nr); 1786 pg_vec = NULL; 1787 goto out; 1788 } 1789 1790 static int packet_set_ring(struct sock *sk, struct tpacket_req *req, int closing) 1791 { 1792 char **pg_vec = NULL; 1793 struct packet_sock *po = pkt_sk(sk); 1794 int was_running, order = 0; 1795 __be16 num; 1796 int err = 0; 1797 1798 if (req->tp_block_nr) { 1799 int i; 1800 1801 /* Sanity tests and some calculations */ 1802 1803 if (unlikely(po->pg_vec)) 1804 return -EBUSY; 1805 1806 switch (po->tp_version) { 1807 case TPACKET_V1: 1808 po->tp_hdrlen = TPACKET_HDRLEN; 1809 break; 1810 case TPACKET_V2: 1811 po->tp_hdrlen = TPACKET2_HDRLEN; 1812 break; 1813 } 1814 1815 if (unlikely((int)req->tp_block_size <= 0)) 1816 return -EINVAL; 1817 if (unlikely(req->tp_block_size & (PAGE_SIZE - 1))) 1818 return -EINVAL; 1819 if (unlikely(req->tp_frame_size < po->tp_hdrlen + 1820 po->tp_reserve)) 1821 return -EINVAL; 1822 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1))) 1823 return -EINVAL; 1824 1825 po->frames_per_block = req->tp_block_size/req->tp_frame_size; 1826 if (unlikely(po->frames_per_block <= 0)) 1827 return -EINVAL; 1828 if (unlikely((po->frames_per_block * req->tp_block_nr) != 1829 req->tp_frame_nr)) 1830 return -EINVAL; 1831 1832 err = -ENOMEM; 1833 order = get_order(req->tp_block_size); 1834 pg_vec = alloc_pg_vec(req, order); 1835 if (unlikely(!pg_vec)) 1836 goto out; 1837 1838 for (i = 0; i < req->tp_block_nr; i++) { 1839 void *ptr = pg_vec[i]; 1840 int k; 1841 1842 for (k = 0; k < po->frames_per_block; k++) { 1843 __packet_set_status(po, ptr, TP_STATUS_KERNEL); 1844 ptr += req->tp_frame_size; 1845 } 1846 } 1847 /* Done */ 1848 } else { 1849 if (unlikely(req->tp_frame_nr)) 1850 return -EINVAL; 1851 } 1852 1853 lock_sock(sk); 1854 1855 /* Detach socket from network */ 1856 spin_lock(&po->bind_lock); 1857 was_running = po->running; 1858 num = po->num; 1859 if (was_running) { 1860 __dev_remove_pack(&po->prot_hook); 1861 po->num = 0; 1862 po->running = 0; 1863 __sock_put(sk); 1864 } 1865 spin_unlock(&po->bind_lock); 1866 1867 synchronize_net(); 1868 1869 err = -EBUSY; 1870 mutex_lock(&po->pg_vec_lock); 1871 if (closing || atomic_read(&po->mapped) == 0) { 1872 err = 0; 1873 #define XC(a, b) ({ __typeof__ ((a)) __t; __t = (a); (a) = (b); __t; }) 1874 1875 spin_lock_bh(&sk->sk_receive_queue.lock); 1876 pg_vec = XC(po->pg_vec, pg_vec); 1877 po->frame_max = (req->tp_frame_nr - 1); 1878 po->head = 0; 1879 po->frame_size = req->tp_frame_size; 1880 spin_unlock_bh(&sk->sk_receive_queue.lock); 1881 1882 order = XC(po->pg_vec_order, order); 1883 req->tp_block_nr = XC(po->pg_vec_len, req->tp_block_nr); 1884 1885 po->pg_vec_pages = req->tp_block_size/PAGE_SIZE; 1886 po->prot_hook.func = po->pg_vec ? tpacket_rcv : packet_rcv; 1887 skb_queue_purge(&sk->sk_receive_queue); 1888 #undef XC 1889 if (atomic_read(&po->mapped)) 1890 printk(KERN_DEBUG "packet_mmap: vma is busy: %d\n", atomic_read(&po->mapped)); 1891 } 1892 mutex_unlock(&po->pg_vec_lock); 1893 1894 spin_lock(&po->bind_lock); 1895 if (was_running && !po->running) { 1896 sock_hold(sk); 1897 po->running = 1; 1898 po->num = num; 1899 dev_add_pack(&po->prot_hook); 1900 } 1901 spin_unlock(&po->bind_lock); 1902 1903 release_sock(sk); 1904 1905 if (pg_vec) 1906 free_pg_vec(pg_vec, order, req->tp_block_nr); 1907 out: 1908 return err; 1909 } 1910 1911 static int packet_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma) 1912 { 1913 struct sock *sk = sock->sk; 1914 struct packet_sock *po = pkt_sk(sk); 1915 unsigned long size; 1916 unsigned long start; 1917 int err = -EINVAL; 1918 int i; 1919 1920 if (vma->vm_pgoff) 1921 return -EINVAL; 1922 1923 size = vma->vm_end - vma->vm_start; 1924 1925 mutex_lock(&po->pg_vec_lock); 1926 if (po->pg_vec == NULL) 1927 goto out; 1928 if (size != po->pg_vec_len*po->pg_vec_pages*PAGE_SIZE) 1929 goto out; 1930 1931 start = vma->vm_start; 1932 for (i = 0; i < po->pg_vec_len; i++) { 1933 struct page *page = virt_to_page(po->pg_vec[i]); 1934 int pg_num; 1935 1936 for (pg_num = 0; pg_num < po->pg_vec_pages; pg_num++, page++) { 1937 err = vm_insert_page(vma, start, page); 1938 if (unlikely(err)) 1939 goto out; 1940 start += PAGE_SIZE; 1941 } 1942 } 1943 atomic_inc(&po->mapped); 1944 vma->vm_ops = &packet_mmap_ops; 1945 err = 0; 1946 1947 out: 1948 mutex_unlock(&po->pg_vec_lock); 1949 return err; 1950 } 1951 #endif 1952 1953 1954 static const struct proto_ops packet_ops_spkt = { 1955 .family = PF_PACKET, 1956 .owner = THIS_MODULE, 1957 .release = packet_release, 1958 .bind = packet_bind_spkt, 1959 .connect = sock_no_connect, 1960 .socketpair = sock_no_socketpair, 1961 .accept = sock_no_accept, 1962 .getname = packet_getname_spkt, 1963 .poll = datagram_poll, 1964 .ioctl = packet_ioctl, 1965 .listen = sock_no_listen, 1966 .shutdown = sock_no_shutdown, 1967 .setsockopt = sock_no_setsockopt, 1968 .getsockopt = sock_no_getsockopt, 1969 .sendmsg = packet_sendmsg_spkt, 1970 .recvmsg = packet_recvmsg, 1971 .mmap = sock_no_mmap, 1972 .sendpage = sock_no_sendpage, 1973 }; 1974 1975 static const struct proto_ops packet_ops = { 1976 .family = PF_PACKET, 1977 .owner = THIS_MODULE, 1978 .release = packet_release, 1979 .bind = packet_bind, 1980 .connect = sock_no_connect, 1981 .socketpair = sock_no_socketpair, 1982 .accept = sock_no_accept, 1983 .getname = packet_getname, 1984 .poll = packet_poll, 1985 .ioctl = packet_ioctl, 1986 .listen = sock_no_listen, 1987 .shutdown = sock_no_shutdown, 1988 .setsockopt = packet_setsockopt, 1989 .getsockopt = packet_getsockopt, 1990 .sendmsg = packet_sendmsg, 1991 .recvmsg = packet_recvmsg, 1992 .mmap = packet_mmap, 1993 .sendpage = sock_no_sendpage, 1994 }; 1995 1996 static struct net_proto_family packet_family_ops = { 1997 .family = PF_PACKET, 1998 .create = packet_create, 1999 .owner = THIS_MODULE, 2000 }; 2001 2002 static struct notifier_block packet_netdev_notifier = { 2003 .notifier_call =packet_notifier, 2004 }; 2005 2006 #ifdef CONFIG_PROC_FS 2007 static inline struct sock *packet_seq_idx(struct net *net, loff_t off) 2008 { 2009 struct sock *s; 2010 struct hlist_node *node; 2011 2012 sk_for_each(s, node, &net->packet.sklist) { 2013 if (!off--) 2014 return s; 2015 } 2016 return NULL; 2017 } 2018 2019 static void *packet_seq_start(struct seq_file *seq, loff_t *pos) 2020 __acquires(seq_file_net(seq)->packet.sklist_lock) 2021 { 2022 struct net *net = seq_file_net(seq); 2023 read_lock(&net->packet.sklist_lock); 2024 return *pos ? packet_seq_idx(net, *pos - 1) : SEQ_START_TOKEN; 2025 } 2026 2027 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2028 { 2029 struct net *net = seq_file_net(seq); 2030 ++*pos; 2031 return (v == SEQ_START_TOKEN) 2032 ? sk_head(&net->packet.sklist) 2033 : sk_next((struct sock*)v) ; 2034 } 2035 2036 static void packet_seq_stop(struct seq_file *seq, void *v) 2037 __releases(seq_file_net(seq)->packet.sklist_lock) 2038 { 2039 struct net *net = seq_file_net(seq); 2040 read_unlock(&net->packet.sklist_lock); 2041 } 2042 2043 static int packet_seq_show(struct seq_file *seq, void *v) 2044 { 2045 if (v == SEQ_START_TOKEN) 2046 seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n"); 2047 else { 2048 struct sock *s = v; 2049 const struct packet_sock *po = pkt_sk(s); 2050 2051 seq_printf(seq, 2052 "%p %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n", 2053 s, 2054 atomic_read(&s->sk_refcnt), 2055 s->sk_type, 2056 ntohs(po->num), 2057 po->ifindex, 2058 po->running, 2059 atomic_read(&s->sk_rmem_alloc), 2060 sock_i_uid(s), 2061 sock_i_ino(s) ); 2062 } 2063 2064 return 0; 2065 } 2066 2067 static const struct seq_operations packet_seq_ops = { 2068 .start = packet_seq_start, 2069 .next = packet_seq_next, 2070 .stop = packet_seq_stop, 2071 .show = packet_seq_show, 2072 }; 2073 2074 static int packet_seq_open(struct inode *inode, struct file *file) 2075 { 2076 return seq_open_net(inode, file, &packet_seq_ops, 2077 sizeof(struct seq_net_private)); 2078 } 2079 2080 static const struct file_operations packet_seq_fops = { 2081 .owner = THIS_MODULE, 2082 .open = packet_seq_open, 2083 .read = seq_read, 2084 .llseek = seq_lseek, 2085 .release = seq_release_net, 2086 }; 2087 2088 #endif 2089 2090 static int packet_net_init(struct net *net) 2091 { 2092 rwlock_init(&net->packet.sklist_lock); 2093 INIT_HLIST_HEAD(&net->packet.sklist); 2094 2095 if (!proc_net_fops_create(net, "packet", 0, &packet_seq_fops)) 2096 return -ENOMEM; 2097 2098 return 0; 2099 } 2100 2101 static void packet_net_exit(struct net *net) 2102 { 2103 proc_net_remove(net, "packet"); 2104 } 2105 2106 static struct pernet_operations packet_net_ops = { 2107 .init = packet_net_init, 2108 .exit = packet_net_exit, 2109 }; 2110 2111 2112 static void __exit packet_exit(void) 2113 { 2114 unregister_netdevice_notifier(&packet_netdev_notifier); 2115 unregister_pernet_subsys(&packet_net_ops); 2116 sock_unregister(PF_PACKET); 2117 proto_unregister(&packet_proto); 2118 } 2119 2120 static int __init packet_init(void) 2121 { 2122 int rc = proto_register(&packet_proto, 0); 2123 2124 if (rc != 0) 2125 goto out; 2126 2127 sock_register(&packet_family_ops); 2128 register_pernet_subsys(&packet_net_ops); 2129 register_netdevice_notifier(&packet_netdev_notifier); 2130 out: 2131 return rc; 2132 } 2133 2134 module_init(packet_init); 2135 module_exit(packet_exit); 2136 MODULE_LICENSE("GPL"); 2137 MODULE_ALIAS_NETPROTO(PF_PACKET); 2138