bpf.c revision 243799
1/*- 2 * Copyright (c) 1990, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from the Stanford/CMU enet packet filter, 6 * (net/enet.c) distributed as part of 4.3BSD, and code contributed 7 * to Berkeley by Steven McCanne and Van Jacobson both of Lawrence 8 * Berkeley Laboratory. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)bpf.c 8.4 (Berkeley) 1/9/95 35 */ 36 37#include <sys/cdefs.h> 38__FBSDID("$FreeBSD: head/sys/net/bpf.c 243799 2012-12-02 21:43:37Z melifaro $"); 39 40#include "opt_bpf.h" 41#include "opt_compat.h" 42#include "opt_netgraph.h" 43 44#include <sys/types.h> 45#include <sys/param.h> 46#include <sys/lock.h> 47#include <sys/rwlock.h> 48#include <sys/systm.h> 49#include <sys/conf.h> 50#include <sys/fcntl.h> 51#include <sys/jail.h> 52#include <sys/malloc.h> 53#include <sys/mbuf.h> 54#include <sys/time.h> 55#include <sys/priv.h> 56#include <sys/proc.h> 57#include <sys/signalvar.h> 58#include <sys/filio.h> 59#include <sys/sockio.h> 60#include <sys/ttycom.h> 61#include <sys/uio.h> 62 63#include <sys/event.h> 64#include <sys/file.h> 65#include <sys/poll.h> 66#include <sys/proc.h> 67 68#include <sys/socket.h> 69 70#include <net/if.h> 71#define BPF_INTERNAL 72#include <net/bpf.h> 73#include <net/bpf_buffer.h> 74#ifdef BPF_JITTER 75#include <net/bpf_jitter.h> 76#endif 77#include <net/bpf_zerocopy.h> 78#include <net/bpfdesc.h> 79#include <net/vnet.h> 80 81#include <netinet/in.h> 82#include <netinet/if_ether.h> 83#include <sys/kernel.h> 84#include <sys/sysctl.h> 85 86#include <net80211/ieee80211_freebsd.h> 87 88#include <security/mac/mac_framework.h> 89 90MALLOC_DEFINE(M_BPF, "BPF", "BPF data"); 91 92#if defined(DEV_BPF) || defined(NETGRAPH_BPF) 93 94#define PRINET 26 /* interruptible */ 95 96#define SIZEOF_BPF_HDR(type) \ 97 (offsetof(type, bh_hdrlen) + sizeof(((type *)0)->bh_hdrlen)) 98 99#ifdef COMPAT_FREEBSD32 100#include <sys/mount.h> 101#include <compat/freebsd32/freebsd32.h> 102#define BPF_ALIGNMENT32 sizeof(int32_t) 103#define BPF_WORDALIGN32(x) (((x)+(BPF_ALIGNMENT32-1))&~(BPF_ALIGNMENT32-1)) 104 105#ifndef BURN_BRIDGES 106/* 107 * 32-bit version of structure prepended to each packet. We use this header 108 * instead of the standard one for 32-bit streams. We mark the a stream as 109 * 32-bit the first time we see a 32-bit compat ioctl request. 110 */ 111struct bpf_hdr32 { 112 struct timeval32 bh_tstamp; /* time stamp */ 113 uint32_t bh_caplen; /* length of captured portion */ 114 uint32_t bh_datalen; /* original length of packet */ 115 uint16_t bh_hdrlen; /* length of bpf header (this struct 116 plus alignment padding) */ 117}; 118#endif 119 120struct bpf_program32 { 121 u_int bf_len; 122 uint32_t bf_insns; 123}; 124 125struct bpf_dltlist32 { 126 u_int bfl_len; 127 u_int bfl_list; 128}; 129 130#define BIOCSETF32 _IOW('B', 103, struct bpf_program32) 131#define BIOCSRTIMEOUT32 _IOW('B', 109, struct timeval32) 132#define BIOCGRTIMEOUT32 _IOR('B', 110, struct timeval32) 133#define BIOCGDLTLIST32 _IOWR('B', 121, struct bpf_dltlist32) 134#define BIOCSETWF32 _IOW('B', 123, struct bpf_program32) 135#define BIOCSETFNR32 _IOW('B', 130, struct bpf_program32) 136#endif 137 138/* 139 * bpf_iflist is a list of BPF interface structures, each corresponding to a 140 * specific DLT. The same network interface might have several BPF interface 141 * structures registered by different layers in the stack (i.e., 802.11 142 * frames, ethernet frames, etc). 143 */ 144static LIST_HEAD(, bpf_if) bpf_iflist, bpf_freelist; 145static struct mtx bpf_mtx; /* bpf global lock */ 146static int bpf_bpfd_cnt; 147 148static void bpf_attachd(struct bpf_d *, struct bpf_if *); 149static void bpf_detachd(struct bpf_d *); 150static void bpf_detachd_locked(struct bpf_d *); 151static void bpf_freed(struct bpf_d *); 152static int bpf_movein(struct uio *, int, struct ifnet *, struct mbuf **, 153 struct sockaddr *, int *, struct bpf_insn *); 154static int bpf_setif(struct bpf_d *, struct ifreq *); 155static void bpf_timed_out(void *); 156static __inline void 157 bpf_wakeup(struct bpf_d *); 158static void catchpacket(struct bpf_d *, u_char *, u_int, u_int, 159 void (*)(struct bpf_d *, caddr_t, u_int, void *, u_int), 160 struct bintime *); 161static void reset_d(struct bpf_d *); 162static int bpf_setf(struct bpf_d *, struct bpf_program *, u_long cmd); 163static int bpf_getdltlist(struct bpf_d *, struct bpf_dltlist *); 164static int bpf_setdlt(struct bpf_d *, u_int); 165static void filt_bpfdetach(struct knote *); 166static int filt_bpfread(struct knote *, long); 167static void bpf_drvinit(void *); 168static int bpf_stats_sysctl(SYSCTL_HANDLER_ARGS); 169 170SYSCTL_NODE(_net, OID_AUTO, bpf, CTLFLAG_RW, 0, "bpf sysctl"); 171int bpf_maxinsns = BPF_MAXINSNS; 172SYSCTL_INT(_net_bpf, OID_AUTO, maxinsns, CTLFLAG_RW, 173 &bpf_maxinsns, 0, "Maximum bpf program instructions"); 174static int bpf_zerocopy_enable = 0; 175SYSCTL_INT(_net_bpf, OID_AUTO, zerocopy_enable, CTLFLAG_RW, 176 &bpf_zerocopy_enable, 0, "Enable new zero-copy BPF buffer sessions"); 177static SYSCTL_NODE(_net_bpf, OID_AUTO, stats, CTLFLAG_MPSAFE | CTLFLAG_RW, 178 bpf_stats_sysctl, "bpf statistics portal"); 179 180static VNET_DEFINE(int, bpf_optimize_writers) = 0; 181#define V_bpf_optimize_writers VNET(bpf_optimize_writers) 182SYSCTL_VNET_INT(_net_bpf, OID_AUTO, optimize_writers, 183 CTLFLAG_RW, &VNET_NAME(bpf_optimize_writers), 0, 184 "Do not send packets until BPF program is set"); 185 186static d_open_t bpfopen; 187static d_read_t bpfread; 188static d_write_t bpfwrite; 189static d_ioctl_t bpfioctl; 190static d_poll_t bpfpoll; 191static d_kqfilter_t bpfkqfilter; 192 193static struct cdevsw bpf_cdevsw = { 194 .d_version = D_VERSION, 195 .d_open = bpfopen, 196 .d_read = bpfread, 197 .d_write = bpfwrite, 198 .d_ioctl = bpfioctl, 199 .d_poll = bpfpoll, 200 .d_name = "bpf", 201 .d_kqfilter = bpfkqfilter, 202}; 203 204static struct filterops bpfread_filtops = { 205 .f_isfd = 1, 206 .f_detach = filt_bpfdetach, 207 .f_event = filt_bpfread, 208}; 209 210eventhandler_tag bpf_ifdetach_cookie = NULL; 211 212/* 213 * LOCKING MODEL USED BY BPF: 214 * Locks: 215 * 1) global lock (BPF_LOCK). Mutex, used to protect interface addition/removal, 216 * some global counters and every bpf_if reference. 217 * 2) Interface lock. Rwlock, used to protect list of BPF descriptors and their filters. 218 * 3) Descriptor lock. Mutex, used to protect BPF buffers and various structure fields 219 * used by bpf_mtap code. 220 * 221 * Lock order: 222 * 223 * Global lock, interface lock, descriptor lock 224 * 225 * We have to acquire interface lock before descriptor main lock due to BPF_MTAP[2] 226 * working model. In many places (like bpf_detachd) we start with BPF descriptor 227 * (and we need to at least rlock it to get reliable interface pointer). This 228 * gives us potential LOR. As a result, we use global lock to protect from bpf_if 229 * change in every such place. 230 * 231 * Changing d->bd_bif is protected by 1) global lock, 2) interface lock and 232 * 3) descriptor main wlock. 233 * Reading bd_bif can be protected by any of these locks, typically global lock. 234 * 235 * Changing read/write BPF filter is protected by the same three locks, 236 * the same applies for reading. 237 * 238 * Sleeping in global lock is not allowed due to bpfdetach() using it. 239 */ 240 241/* 242 * Wrapper functions for various buffering methods. If the set of buffer 243 * modes expands, we will probably want to introduce a switch data structure 244 * similar to protosw, et. 245 */ 246static void 247bpf_append_bytes(struct bpf_d *d, caddr_t buf, u_int offset, void *src, 248 u_int len) 249{ 250 251 BPFD_LOCK_ASSERT(d); 252 253 switch (d->bd_bufmode) { 254 case BPF_BUFMODE_BUFFER: 255 return (bpf_buffer_append_bytes(d, buf, offset, src, len)); 256 257 case BPF_BUFMODE_ZBUF: 258 d->bd_zcopy++; 259 return (bpf_zerocopy_append_bytes(d, buf, offset, src, len)); 260 261 default: 262 panic("bpf_buf_append_bytes"); 263 } 264} 265 266static void 267bpf_append_mbuf(struct bpf_d *d, caddr_t buf, u_int offset, void *src, 268 u_int len) 269{ 270 271 BPFD_LOCK_ASSERT(d); 272 273 switch (d->bd_bufmode) { 274 case BPF_BUFMODE_BUFFER: 275 return (bpf_buffer_append_mbuf(d, buf, offset, src, len)); 276 277 case BPF_BUFMODE_ZBUF: 278 d->bd_zcopy++; 279 return (bpf_zerocopy_append_mbuf(d, buf, offset, src, len)); 280 281 default: 282 panic("bpf_buf_append_mbuf"); 283 } 284} 285 286/* 287 * This function gets called when the free buffer is re-assigned. 288 */ 289static void 290bpf_buf_reclaimed(struct bpf_d *d) 291{ 292 293 BPFD_LOCK_ASSERT(d); 294 295 switch (d->bd_bufmode) { 296 case BPF_BUFMODE_BUFFER: 297 return; 298 299 case BPF_BUFMODE_ZBUF: 300 bpf_zerocopy_buf_reclaimed(d); 301 return; 302 303 default: 304 panic("bpf_buf_reclaimed"); 305 } 306} 307 308/* 309 * If the buffer mechanism has a way to decide that a held buffer can be made 310 * free, then it is exposed via the bpf_canfreebuf() interface. (1) is 311 * returned if the buffer can be discarded, (0) is returned if it cannot. 312 */ 313static int 314bpf_canfreebuf(struct bpf_d *d) 315{ 316 317 BPFD_LOCK_ASSERT(d); 318 319 switch (d->bd_bufmode) { 320 case BPF_BUFMODE_ZBUF: 321 return (bpf_zerocopy_canfreebuf(d)); 322 } 323 return (0); 324} 325 326/* 327 * Allow the buffer model to indicate that the current store buffer is 328 * immutable, regardless of the appearance of space. Return (1) if the 329 * buffer is writable, and (0) if not. 330 */ 331static int 332bpf_canwritebuf(struct bpf_d *d) 333{ 334 BPFD_LOCK_ASSERT(d); 335 336 switch (d->bd_bufmode) { 337 case BPF_BUFMODE_ZBUF: 338 return (bpf_zerocopy_canwritebuf(d)); 339 } 340 return (1); 341} 342 343/* 344 * Notify buffer model that an attempt to write to the store buffer has 345 * resulted in a dropped packet, in which case the buffer may be considered 346 * full. 347 */ 348static void 349bpf_buffull(struct bpf_d *d) 350{ 351 352 BPFD_LOCK_ASSERT(d); 353 354 switch (d->bd_bufmode) { 355 case BPF_BUFMODE_ZBUF: 356 bpf_zerocopy_buffull(d); 357 break; 358 } 359} 360 361/* 362 * Notify the buffer model that a buffer has moved into the hold position. 363 */ 364void 365bpf_bufheld(struct bpf_d *d) 366{ 367 368 BPFD_LOCK_ASSERT(d); 369 370 switch (d->bd_bufmode) { 371 case BPF_BUFMODE_ZBUF: 372 bpf_zerocopy_bufheld(d); 373 break; 374 } 375} 376 377static void 378bpf_free(struct bpf_d *d) 379{ 380 381 switch (d->bd_bufmode) { 382 case BPF_BUFMODE_BUFFER: 383 return (bpf_buffer_free(d)); 384 385 case BPF_BUFMODE_ZBUF: 386 return (bpf_zerocopy_free(d)); 387 388 default: 389 panic("bpf_buf_free"); 390 } 391} 392 393static int 394bpf_uiomove(struct bpf_d *d, caddr_t buf, u_int len, struct uio *uio) 395{ 396 397 if (d->bd_bufmode != BPF_BUFMODE_BUFFER) 398 return (EOPNOTSUPP); 399 return (bpf_buffer_uiomove(d, buf, len, uio)); 400} 401 402static int 403bpf_ioctl_sblen(struct bpf_d *d, u_int *i) 404{ 405 406 if (d->bd_bufmode != BPF_BUFMODE_BUFFER) 407 return (EOPNOTSUPP); 408 return (bpf_buffer_ioctl_sblen(d, i)); 409} 410 411static int 412bpf_ioctl_getzmax(struct thread *td, struct bpf_d *d, size_t *i) 413{ 414 415 if (d->bd_bufmode != BPF_BUFMODE_ZBUF) 416 return (EOPNOTSUPP); 417 return (bpf_zerocopy_ioctl_getzmax(td, d, i)); 418} 419 420static int 421bpf_ioctl_rotzbuf(struct thread *td, struct bpf_d *d, struct bpf_zbuf *bz) 422{ 423 424 if (d->bd_bufmode != BPF_BUFMODE_ZBUF) 425 return (EOPNOTSUPP); 426 return (bpf_zerocopy_ioctl_rotzbuf(td, d, bz)); 427} 428 429static int 430bpf_ioctl_setzbuf(struct thread *td, struct bpf_d *d, struct bpf_zbuf *bz) 431{ 432 433 if (d->bd_bufmode != BPF_BUFMODE_ZBUF) 434 return (EOPNOTSUPP); 435 return (bpf_zerocopy_ioctl_setzbuf(td, d, bz)); 436} 437 438/* 439 * General BPF functions. 440 */ 441static int 442bpf_movein(struct uio *uio, int linktype, struct ifnet *ifp, struct mbuf **mp, 443 struct sockaddr *sockp, int *hdrlen, struct bpf_insn *wfilter) 444{ 445 const struct ieee80211_bpf_params *p; 446 struct ether_header *eh; 447 struct mbuf *m; 448 int error; 449 int len; 450 int hlen; 451 int slen; 452 453 /* 454 * Build a sockaddr based on the data link layer type. 455 * We do this at this level because the ethernet header 456 * is copied directly into the data field of the sockaddr. 457 * In the case of SLIP, there is no header and the packet 458 * is forwarded as is. 459 * Also, we are careful to leave room at the front of the mbuf 460 * for the link level header. 461 */ 462 switch (linktype) { 463 464 case DLT_SLIP: 465 sockp->sa_family = AF_INET; 466 hlen = 0; 467 break; 468 469 case DLT_EN10MB: 470 sockp->sa_family = AF_UNSPEC; 471 /* XXX Would MAXLINKHDR be better? */ 472 hlen = ETHER_HDR_LEN; 473 break; 474 475 case DLT_FDDI: 476 sockp->sa_family = AF_IMPLINK; 477 hlen = 0; 478 break; 479 480 case DLT_RAW: 481 sockp->sa_family = AF_UNSPEC; 482 hlen = 0; 483 break; 484 485 case DLT_NULL: 486 /* 487 * null interface types require a 4 byte pseudo header which 488 * corresponds to the address family of the packet. 489 */ 490 sockp->sa_family = AF_UNSPEC; 491 hlen = 4; 492 break; 493 494 case DLT_ATM_RFC1483: 495 /* 496 * en atm driver requires 4-byte atm pseudo header. 497 * though it isn't standard, vpi:vci needs to be 498 * specified anyway. 499 */ 500 sockp->sa_family = AF_UNSPEC; 501 hlen = 12; /* XXX 4(ATM_PH) + 3(LLC) + 5(SNAP) */ 502 break; 503 504 case DLT_PPP: 505 sockp->sa_family = AF_UNSPEC; 506 hlen = 4; /* This should match PPP_HDRLEN */ 507 break; 508 509 case DLT_IEEE802_11: /* IEEE 802.11 wireless */ 510 sockp->sa_family = AF_IEEE80211; 511 hlen = 0; 512 break; 513 514 case DLT_IEEE802_11_RADIO: /* IEEE 802.11 wireless w/ phy params */ 515 sockp->sa_family = AF_IEEE80211; 516 sockp->sa_len = 12; /* XXX != 0 */ 517 hlen = sizeof(struct ieee80211_bpf_params); 518 break; 519 520 default: 521 return (EIO); 522 } 523 524 len = uio->uio_resid; 525 526 if (len - hlen > ifp->if_mtu) 527 return (EMSGSIZE); 528 529 if ((unsigned)len > MJUM16BYTES) 530 return (EIO); 531 532 if (len <= MHLEN) 533 MGETHDR(m, M_WAIT, MT_DATA); 534 else if (len <= MCLBYTES) 535 m = m_getcl(M_WAIT, MT_DATA, M_PKTHDR); 536 else 537 m = m_getjcl(M_WAIT, MT_DATA, M_PKTHDR, 538#if (MJUMPAGESIZE > MCLBYTES) 539 len <= MJUMPAGESIZE ? MJUMPAGESIZE : 540#endif 541 (len <= MJUM9BYTES ? MJUM9BYTES : MJUM16BYTES)); 542 m->m_pkthdr.len = m->m_len = len; 543 m->m_pkthdr.rcvif = NULL; 544 *mp = m; 545 546 if (m->m_len < hlen) { 547 error = EPERM; 548 goto bad; 549 } 550 551 error = uiomove(mtod(m, u_char *), len, uio); 552 if (error) 553 goto bad; 554 555 slen = bpf_filter(wfilter, mtod(m, u_char *), len, len); 556 if (slen == 0) { 557 error = EPERM; 558 goto bad; 559 } 560 561 /* Check for multicast destination */ 562 switch (linktype) { 563 case DLT_EN10MB: 564 eh = mtod(m, struct ether_header *); 565 if (ETHER_IS_MULTICAST(eh->ether_dhost)) { 566 if (bcmp(ifp->if_broadcastaddr, eh->ether_dhost, 567 ETHER_ADDR_LEN) == 0) 568 m->m_flags |= M_BCAST; 569 else 570 m->m_flags |= M_MCAST; 571 } 572 break; 573 } 574 575 /* 576 * Make room for link header, and copy it to sockaddr 577 */ 578 if (hlen != 0) { 579 if (sockp->sa_family == AF_IEEE80211) { 580 /* 581 * Collect true length from the parameter header 582 * NB: sockp is known to be zero'd so if we do a 583 * short copy unspecified parameters will be 584 * zero. 585 * NB: packet may not be aligned after stripping 586 * bpf params 587 * XXX check ibp_vers 588 */ 589 p = mtod(m, const struct ieee80211_bpf_params *); 590 hlen = p->ibp_len; 591 if (hlen > sizeof(sockp->sa_data)) { 592 error = EINVAL; 593 goto bad; 594 } 595 } 596 bcopy(m->m_data, sockp->sa_data, hlen); 597 } 598 *hdrlen = hlen; 599 600 return (0); 601bad: 602 m_freem(m); 603 return (error); 604} 605 606/* 607 * Attach file to the bpf interface, i.e. make d listen on bp. 608 */ 609static void 610bpf_attachd(struct bpf_d *d, struct bpf_if *bp) 611{ 612 int op_w; 613 614 BPF_LOCK_ASSERT(); 615 616 /* 617 * Save sysctl value to protect from sysctl change 618 * between reads 619 */ 620 op_w = V_bpf_optimize_writers; 621 622 if (d->bd_bif != NULL) 623 bpf_detachd_locked(d); 624 /* 625 * Point d at bp, and add d to the interface's list. 626 * Since there are many applicaiotns using BPF for 627 * sending raw packets only (dhcpd, cdpd are good examples) 628 * we can delay adding d to the list of active listeners until 629 * some filter is configured. 630 */ 631 632 BPFIF_WLOCK(bp); 633 BPFD_LOCK(d); 634 635 d->bd_bif = bp; 636 637 if (op_w != 0) { 638 /* Add to writers-only list */ 639 LIST_INSERT_HEAD(&bp->bif_wlist, d, bd_next); 640 /* 641 * We decrement bd_writer on every filter set operation. 642 * First BIOCSETF is done by pcap_open_live() to set up 643 * snap length. After that appliation usually sets its own filter 644 */ 645 d->bd_writer = 2; 646 } else 647 LIST_INSERT_HEAD(&bp->bif_dlist, d, bd_next); 648 649 BPFD_UNLOCK(d); 650 BPFIF_WUNLOCK(bp); 651 652 bpf_bpfd_cnt++; 653 654 CTR3(KTR_NET, "%s: bpf_attach called by pid %d, adding to %s list", 655 __func__, d->bd_pid, d->bd_writer ? "writer" : "active"); 656 657 if (op_w == 0) 658 EVENTHANDLER_INVOKE(bpf_track, bp->bif_ifp, bp->bif_dlt, 1); 659} 660 661/* 662 * Add d to the list of active bp filters. 663 * Reuqires bpf_attachd() to be called before 664 */ 665static void 666bpf_upgraded(struct bpf_d *d) 667{ 668 struct bpf_if *bp; 669 670 BPF_LOCK_ASSERT(); 671 672 bp = d->bd_bif; 673 674 /* 675 * Filter can be set several times without specifying interface. 676 * Mark d as reader and exit. 677 */ 678 if (bp == NULL) { 679 BPFD_LOCK(d); 680 d->bd_writer = 0; 681 BPFD_UNLOCK(d); 682 return; 683 } 684 685 BPFIF_WLOCK(bp); 686 BPFD_LOCK(d); 687 688 /* Remove from writers-only list */ 689 LIST_REMOVE(d, bd_next); 690 LIST_INSERT_HEAD(&bp->bif_dlist, d, bd_next); 691 /* Mark d as reader */ 692 d->bd_writer = 0; 693 694 BPFD_UNLOCK(d); 695 BPFIF_WUNLOCK(bp); 696 697 CTR2(KTR_NET, "%s: upgrade required by pid %d", __func__, d->bd_pid); 698 699 EVENTHANDLER_INVOKE(bpf_track, bp->bif_ifp, bp->bif_dlt, 1); 700} 701 702/* 703 * Detach a file from its interface. 704 */ 705static void 706bpf_detachd(struct bpf_d *d) 707{ 708 BPF_LOCK(); 709 bpf_detachd_locked(d); 710 BPF_UNLOCK(); 711} 712 713static void 714bpf_detachd_locked(struct bpf_d *d) 715{ 716 int error; 717 struct bpf_if *bp; 718 struct ifnet *ifp; 719 720 CTR2(KTR_NET, "%s: detach required by pid %d", __func__, d->bd_pid); 721 722 BPF_LOCK_ASSERT(); 723 724 /* Check if descriptor is attached */ 725 if ((bp = d->bd_bif) == NULL) 726 return; 727 728 BPFIF_WLOCK(bp); 729 BPFD_LOCK(d); 730 731 /* Save bd_writer value */ 732 error = d->bd_writer; 733 734 /* 735 * Remove d from the interface's descriptor list. 736 */ 737 LIST_REMOVE(d, bd_next); 738 739 ifp = bp->bif_ifp; 740 d->bd_bif = NULL; 741 BPFD_UNLOCK(d); 742 BPFIF_WUNLOCK(bp); 743 744 bpf_bpfd_cnt--; 745 746 /* Call event handler iff d is attached */ 747 if (error == 0) 748 EVENTHANDLER_INVOKE(bpf_track, ifp, bp->bif_dlt, 0); 749 750 /* 751 * Check if this descriptor had requested promiscuous mode. 752 * If so, turn it off. 753 */ 754 if (d->bd_promisc) { 755 d->bd_promisc = 0; 756 CURVNET_SET(ifp->if_vnet); 757 error = ifpromisc(ifp, 0); 758 CURVNET_RESTORE(); 759 if (error != 0 && error != ENXIO) { 760 /* 761 * ENXIO can happen if a pccard is unplugged 762 * Something is really wrong if we were able to put 763 * the driver into promiscuous mode, but can't 764 * take it out. 765 */ 766 if_printf(bp->bif_ifp, 767 "bpf_detach: ifpromisc failed (%d)\n", error); 768 } 769 } 770} 771 772/* 773 * Close the descriptor by detaching it from its interface, 774 * deallocating its buffers, and marking it free. 775 */ 776static void 777bpf_dtor(void *data) 778{ 779 struct bpf_d *d = data; 780 781 BPFD_LOCK(d); 782 if (d->bd_state == BPF_WAITING) 783 callout_stop(&d->bd_callout); 784 d->bd_state = BPF_IDLE; 785 BPFD_UNLOCK(d); 786 funsetown(&d->bd_sigio); 787 bpf_detachd(d); 788#ifdef MAC 789 mac_bpfdesc_destroy(d); 790#endif /* MAC */ 791 seldrain(&d->bd_sel); 792 knlist_destroy(&d->bd_sel.si_note); 793 callout_drain(&d->bd_callout); 794 bpf_freed(d); 795 free(d, M_BPF); 796} 797 798/* 799 * Open ethernet device. Returns ENXIO for illegal minor device number, 800 * EBUSY if file is open by another process. 801 */ 802/* ARGSUSED */ 803static int 804bpfopen(struct cdev *dev, int flags, int fmt, struct thread *td) 805{ 806 struct bpf_d *d; 807 int error, size; 808 809 d = malloc(sizeof(*d), M_BPF, M_WAITOK | M_ZERO); 810 error = devfs_set_cdevpriv(d, bpf_dtor); 811 if (error != 0) { 812 free(d, M_BPF); 813 return (error); 814 } 815 816 /* 817 * For historical reasons, perform a one-time initialization call to 818 * the buffer routines, even though we're not yet committed to a 819 * particular buffer method. 820 */ 821 bpf_buffer_init(d); 822 d->bd_bufmode = BPF_BUFMODE_BUFFER; 823 d->bd_sig = SIGIO; 824 d->bd_direction = BPF_D_INOUT; 825 BPF_PID_REFRESH(d, td); 826#ifdef MAC 827 mac_bpfdesc_init(d); 828 mac_bpfdesc_create(td->td_ucred, d); 829#endif 830 mtx_init(&d->bd_lock, devtoname(dev), "bpf cdev lock", MTX_DEF); 831 callout_init_mtx(&d->bd_callout, &d->bd_lock, 0); 832 knlist_init_mtx(&d->bd_sel.si_note, &d->bd_lock); 833 834 /* Allocate default buffers */ 835 size = d->bd_bufsize; 836 bpf_buffer_ioctl_sblen(d, &size); 837 838 return (0); 839} 840 841/* 842 * bpfread - read next chunk of packets from buffers 843 */ 844static int 845bpfread(struct cdev *dev, struct uio *uio, int ioflag) 846{ 847 struct bpf_d *d; 848 int error; 849 int non_block; 850 int timed_out; 851 852 error = devfs_get_cdevpriv((void **)&d); 853 if (error != 0) 854 return (error); 855 856 /* 857 * Restrict application to use a buffer the same size as 858 * as kernel buffers. 859 */ 860 if (uio->uio_resid != d->bd_bufsize) 861 return (EINVAL); 862 863 non_block = ((ioflag & O_NONBLOCK) != 0); 864 865 BPFD_LOCK(d); 866 BPF_PID_REFRESH_CUR(d); 867 if (d->bd_bufmode != BPF_BUFMODE_BUFFER) { 868 BPFD_UNLOCK(d); 869 return (EOPNOTSUPP); 870 } 871 if (d->bd_state == BPF_WAITING) 872 callout_stop(&d->bd_callout); 873 timed_out = (d->bd_state == BPF_TIMED_OUT); 874 d->bd_state = BPF_IDLE; 875 /* 876 * If the hold buffer is empty, then do a timed sleep, which 877 * ends when the timeout expires or when enough packets 878 * have arrived to fill the store buffer. 879 */ 880 while (d->bd_hbuf == NULL) { 881 if (d->bd_slen != 0) { 882 /* 883 * A packet(s) either arrived since the previous 884 * read or arrived while we were asleep. 885 */ 886 if (d->bd_immediate || non_block || timed_out) { 887 /* 888 * Rotate the buffers and return what's here 889 * if we are in immediate mode, non-blocking 890 * flag is set, or this descriptor timed out. 891 */ 892 ROTATE_BUFFERS(d); 893 break; 894 } 895 } 896 897 /* 898 * No data is available, check to see if the bpf device 899 * is still pointed at a real interface. If not, return 900 * ENXIO so that the userland process knows to rebind 901 * it before using it again. 902 */ 903 if (d->bd_bif == NULL) { 904 BPFD_UNLOCK(d); 905 return (ENXIO); 906 } 907 908 if (non_block) { 909 BPFD_UNLOCK(d); 910 return (EWOULDBLOCK); 911 } 912 error = msleep(d, &d->bd_lock, PRINET|PCATCH, 913 "bpf", d->bd_rtout); 914 if (error == EINTR || error == ERESTART) { 915 BPFD_UNLOCK(d); 916 return (error); 917 } 918 if (error == EWOULDBLOCK) { 919 /* 920 * On a timeout, return what's in the buffer, 921 * which may be nothing. If there is something 922 * in the store buffer, we can rotate the buffers. 923 */ 924 if (d->bd_hbuf) 925 /* 926 * We filled up the buffer in between 927 * getting the timeout and arriving 928 * here, so we don't need to rotate. 929 */ 930 break; 931 932 if (d->bd_slen == 0) { 933 BPFD_UNLOCK(d); 934 return (0); 935 } 936 ROTATE_BUFFERS(d); 937 break; 938 } 939 } 940 /* 941 * At this point, we know we have something in the hold slot. 942 */ 943 BPFD_UNLOCK(d); 944 945 /* 946 * Move data from hold buffer into user space. 947 * We know the entire buffer is transferred since 948 * we checked above that the read buffer is bpf_bufsize bytes. 949 * 950 * XXXRW: More synchronization needed here: what if a second thread 951 * issues a read on the same fd at the same time? Don't want this 952 * getting invalidated. 953 */ 954 error = bpf_uiomove(d, d->bd_hbuf, d->bd_hlen, uio); 955 956 BPFD_LOCK(d); 957 if (d->bd_hbuf != NULL) { 958 /* Free the hold buffer only if it is still valid. */ 959 d->bd_fbuf = d->bd_hbuf; 960 d->bd_hbuf = NULL; 961 d->bd_hlen = 0; 962 bpf_buf_reclaimed(d); 963 } 964 BPFD_UNLOCK(d); 965 966 return (error); 967} 968 969/* 970 * If there are processes sleeping on this descriptor, wake them up. 971 */ 972static __inline void 973bpf_wakeup(struct bpf_d *d) 974{ 975 976 BPFD_LOCK_ASSERT(d); 977 if (d->bd_state == BPF_WAITING) { 978 callout_stop(&d->bd_callout); 979 d->bd_state = BPF_IDLE; 980 } 981 wakeup(d); 982 if (d->bd_async && d->bd_sig && d->bd_sigio) 983 pgsigio(&d->bd_sigio, d->bd_sig, 0); 984 985 selwakeuppri(&d->bd_sel, PRINET); 986 KNOTE_LOCKED(&d->bd_sel.si_note, 0); 987} 988 989static void 990bpf_timed_out(void *arg) 991{ 992 struct bpf_d *d = (struct bpf_d *)arg; 993 994 BPFD_LOCK_ASSERT(d); 995 996 if (callout_pending(&d->bd_callout) || !callout_active(&d->bd_callout)) 997 return; 998 if (d->bd_state == BPF_WAITING) { 999 d->bd_state = BPF_TIMED_OUT; 1000 if (d->bd_slen != 0) 1001 bpf_wakeup(d); 1002 } 1003} 1004 1005static int 1006bpf_ready(struct bpf_d *d) 1007{ 1008 1009 BPFD_LOCK_ASSERT(d); 1010 1011 if (!bpf_canfreebuf(d) && d->bd_hlen != 0) 1012 return (1); 1013 if ((d->bd_immediate || d->bd_state == BPF_TIMED_OUT) && 1014 d->bd_slen != 0) 1015 return (1); 1016 return (0); 1017} 1018 1019static int 1020bpfwrite(struct cdev *dev, struct uio *uio, int ioflag) 1021{ 1022 struct bpf_d *d; 1023 struct ifnet *ifp; 1024 struct mbuf *m, *mc; 1025 struct sockaddr dst; 1026 int error, hlen; 1027 1028 error = devfs_get_cdevpriv((void **)&d); 1029 if (error != 0) 1030 return (error); 1031 1032 BPF_PID_REFRESH_CUR(d); 1033 d->bd_wcount++; 1034 /* XXX: locking required */ 1035 if (d->bd_bif == NULL) { 1036 d->bd_wdcount++; 1037 return (ENXIO); 1038 } 1039 1040 ifp = d->bd_bif->bif_ifp; 1041 1042 if ((ifp->if_flags & IFF_UP) == 0) { 1043 d->bd_wdcount++; 1044 return (ENETDOWN); 1045 } 1046 1047 if (uio->uio_resid == 0) { 1048 d->bd_wdcount++; 1049 return (0); 1050 } 1051 1052 bzero(&dst, sizeof(dst)); 1053 m = NULL; 1054 hlen = 0; 1055 /* XXX: bpf_movein() can sleep */ 1056 error = bpf_movein(uio, (int)d->bd_bif->bif_dlt, ifp, 1057 &m, &dst, &hlen, d->bd_wfilter); 1058 if (error) { 1059 d->bd_wdcount++; 1060 return (error); 1061 } 1062 d->bd_wfcount++; 1063 if (d->bd_hdrcmplt) 1064 dst.sa_family = pseudo_AF_HDRCMPLT; 1065 1066 if (d->bd_feedback) { 1067 mc = m_dup(m, M_DONTWAIT); 1068 if (mc != NULL) 1069 mc->m_pkthdr.rcvif = ifp; 1070 /* Set M_PROMISC for outgoing packets to be discarded. */ 1071 if (d->bd_direction == BPF_D_INOUT) 1072 m->m_flags |= M_PROMISC; 1073 } else 1074 mc = NULL; 1075 1076 m->m_pkthdr.len -= hlen; 1077 m->m_len -= hlen; 1078 m->m_data += hlen; /* XXX */ 1079 1080 CURVNET_SET(ifp->if_vnet); 1081#ifdef MAC 1082 BPFD_LOCK(d); 1083 mac_bpfdesc_create_mbuf(d, m); 1084 if (mc != NULL) 1085 mac_bpfdesc_create_mbuf(d, mc); 1086 BPFD_UNLOCK(d); 1087#endif 1088 1089 error = (*ifp->if_output)(ifp, m, &dst, NULL); 1090 if (error) 1091 d->bd_wdcount++; 1092 1093 if (mc != NULL) { 1094 if (error == 0) 1095 (*ifp->if_input)(ifp, mc); 1096 else 1097 m_freem(mc); 1098 } 1099 CURVNET_RESTORE(); 1100 1101 return (error); 1102} 1103 1104/* 1105 * Reset a descriptor by flushing its packet buffer and clearing the receive 1106 * and drop counts. This is doable for kernel-only buffers, but with 1107 * zero-copy buffers, we can't write to (or rotate) buffers that are 1108 * currently owned by userspace. It would be nice if we could encapsulate 1109 * this logic in the buffer code rather than here. 1110 */ 1111static void 1112reset_d(struct bpf_d *d) 1113{ 1114 1115 BPFD_LOCK_ASSERT(d); 1116 1117 if ((d->bd_hbuf != NULL) && 1118 (d->bd_bufmode != BPF_BUFMODE_ZBUF || bpf_canfreebuf(d))) { 1119 /* Free the hold buffer. */ 1120 d->bd_fbuf = d->bd_hbuf; 1121 d->bd_hbuf = NULL; 1122 d->bd_hlen = 0; 1123 bpf_buf_reclaimed(d); 1124 } 1125 if (bpf_canwritebuf(d)) 1126 d->bd_slen = 0; 1127 d->bd_rcount = 0; 1128 d->bd_dcount = 0; 1129 d->bd_fcount = 0; 1130 d->bd_wcount = 0; 1131 d->bd_wfcount = 0; 1132 d->bd_wdcount = 0; 1133 d->bd_zcopy = 0; 1134} 1135 1136/* 1137 * FIONREAD Check for read packet available. 1138 * SIOCGIFADDR Get interface address - convenient hook to driver. 1139 * BIOCGBLEN Get buffer len [for read()]. 1140 * BIOCSETF Set read filter. 1141 * BIOCSETFNR Set read filter without resetting descriptor. 1142 * BIOCSETWF Set write filter. 1143 * BIOCFLUSH Flush read packet buffer. 1144 * BIOCPROMISC Put interface into promiscuous mode. 1145 * BIOCGDLT Get link layer type. 1146 * BIOCGETIF Get interface name. 1147 * BIOCSETIF Set interface. 1148 * BIOCSRTIMEOUT Set read timeout. 1149 * BIOCGRTIMEOUT Get read timeout. 1150 * BIOCGSTATS Get packet stats. 1151 * BIOCIMMEDIATE Set immediate mode. 1152 * BIOCVERSION Get filter language version. 1153 * BIOCGHDRCMPLT Get "header already complete" flag 1154 * BIOCSHDRCMPLT Set "header already complete" flag 1155 * BIOCGDIRECTION Get packet direction flag 1156 * BIOCSDIRECTION Set packet direction flag 1157 * BIOCGTSTAMP Get time stamp format and resolution. 1158 * BIOCSTSTAMP Set time stamp format and resolution. 1159 * BIOCLOCK Set "locked" flag 1160 * BIOCFEEDBACK Set packet feedback mode. 1161 * BIOCSETZBUF Set current zero-copy buffer locations. 1162 * BIOCGETZMAX Get maximum zero-copy buffer size. 1163 * BIOCROTZBUF Force rotation of zero-copy buffer 1164 * BIOCSETBUFMODE Set buffer mode. 1165 * BIOCGETBUFMODE Get current buffer mode. 1166 */ 1167/* ARGSUSED */ 1168static int 1169bpfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, 1170 struct thread *td) 1171{ 1172 struct bpf_d *d; 1173 int error; 1174 1175 error = devfs_get_cdevpriv((void **)&d); 1176 if (error != 0) 1177 return (error); 1178 1179 /* 1180 * Refresh PID associated with this descriptor. 1181 */ 1182 BPFD_LOCK(d); 1183 BPF_PID_REFRESH(d, td); 1184 if (d->bd_state == BPF_WAITING) 1185 callout_stop(&d->bd_callout); 1186 d->bd_state = BPF_IDLE; 1187 BPFD_UNLOCK(d); 1188 1189 if (d->bd_locked == 1) { 1190 switch (cmd) { 1191 case BIOCGBLEN: 1192 case BIOCFLUSH: 1193 case BIOCGDLT: 1194 case BIOCGDLTLIST: 1195#ifdef COMPAT_FREEBSD32 1196 case BIOCGDLTLIST32: 1197#endif 1198 case BIOCGETIF: 1199 case BIOCGRTIMEOUT: 1200#if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1201 case BIOCGRTIMEOUT32: 1202#endif 1203 case BIOCGSTATS: 1204 case BIOCVERSION: 1205 case BIOCGRSIG: 1206 case BIOCGHDRCMPLT: 1207 case BIOCSTSTAMP: 1208 case BIOCFEEDBACK: 1209 case FIONREAD: 1210 case BIOCLOCK: 1211 case BIOCSRTIMEOUT: 1212#if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1213 case BIOCSRTIMEOUT32: 1214#endif 1215 case BIOCIMMEDIATE: 1216 case TIOCGPGRP: 1217 case BIOCROTZBUF: 1218 break; 1219 default: 1220 return (EPERM); 1221 } 1222 } 1223#ifdef COMPAT_FREEBSD32 1224 /* 1225 * If we see a 32-bit compat ioctl, mark the stream as 32-bit so 1226 * that it will get 32-bit packet headers. 1227 */ 1228 switch (cmd) { 1229 case BIOCSETF32: 1230 case BIOCSETFNR32: 1231 case BIOCSETWF32: 1232 case BIOCGDLTLIST32: 1233 case BIOCGRTIMEOUT32: 1234 case BIOCSRTIMEOUT32: 1235 BPFD_LOCK(d); 1236 d->bd_compat32 = 1; 1237 BPFD_UNLOCK(d); 1238 } 1239#endif 1240 1241 CURVNET_SET(TD_TO_VNET(td)); 1242 switch (cmd) { 1243 1244 default: 1245 error = EINVAL; 1246 break; 1247 1248 /* 1249 * Check for read packet available. 1250 */ 1251 case FIONREAD: 1252 { 1253 int n; 1254 1255 BPFD_LOCK(d); 1256 n = d->bd_slen; 1257 if (d->bd_hbuf) 1258 n += d->bd_hlen; 1259 BPFD_UNLOCK(d); 1260 1261 *(int *)addr = n; 1262 break; 1263 } 1264 1265 case SIOCGIFADDR: 1266 { 1267 struct ifnet *ifp; 1268 1269 if (d->bd_bif == NULL) 1270 error = EINVAL; 1271 else { 1272 ifp = d->bd_bif->bif_ifp; 1273 error = (*ifp->if_ioctl)(ifp, cmd, addr); 1274 } 1275 break; 1276 } 1277 1278 /* 1279 * Get buffer len [for read()]. 1280 */ 1281 case BIOCGBLEN: 1282 BPFD_LOCK(d); 1283 *(u_int *)addr = d->bd_bufsize; 1284 BPFD_UNLOCK(d); 1285 break; 1286 1287 /* 1288 * Set buffer length. 1289 */ 1290 case BIOCSBLEN: 1291 error = bpf_ioctl_sblen(d, (u_int *)addr); 1292 break; 1293 1294 /* 1295 * Set link layer read filter. 1296 */ 1297 case BIOCSETF: 1298 case BIOCSETFNR: 1299 case BIOCSETWF: 1300#ifdef COMPAT_FREEBSD32 1301 case BIOCSETF32: 1302 case BIOCSETFNR32: 1303 case BIOCSETWF32: 1304#endif 1305 error = bpf_setf(d, (struct bpf_program *)addr, cmd); 1306 break; 1307 1308 /* 1309 * Flush read packet buffer. 1310 */ 1311 case BIOCFLUSH: 1312 BPFD_LOCK(d); 1313 reset_d(d); 1314 BPFD_UNLOCK(d); 1315 break; 1316 1317 /* 1318 * Put interface into promiscuous mode. 1319 */ 1320 case BIOCPROMISC: 1321 if (d->bd_bif == NULL) { 1322 /* 1323 * No interface attached yet. 1324 */ 1325 error = EINVAL; 1326 break; 1327 } 1328 if (d->bd_promisc == 0) { 1329 error = ifpromisc(d->bd_bif->bif_ifp, 1); 1330 if (error == 0) 1331 d->bd_promisc = 1; 1332 } 1333 break; 1334 1335 /* 1336 * Get current data link type. 1337 */ 1338 case BIOCGDLT: 1339 BPF_LOCK(); 1340 if (d->bd_bif == NULL) 1341 error = EINVAL; 1342 else 1343 *(u_int *)addr = d->bd_bif->bif_dlt; 1344 BPF_UNLOCK(); 1345 break; 1346 1347 /* 1348 * Get a list of supported data link types. 1349 */ 1350#ifdef COMPAT_FREEBSD32 1351 case BIOCGDLTLIST32: 1352 { 1353 struct bpf_dltlist32 *list32; 1354 struct bpf_dltlist dltlist; 1355 1356 list32 = (struct bpf_dltlist32 *)addr; 1357 dltlist.bfl_len = list32->bfl_len; 1358 dltlist.bfl_list = PTRIN(list32->bfl_list); 1359 BPF_LOCK(); 1360 if (d->bd_bif == NULL) 1361 error = EINVAL; 1362 else { 1363 error = bpf_getdltlist(d, &dltlist); 1364 if (error == 0) 1365 list32->bfl_len = dltlist.bfl_len; 1366 } 1367 BPF_UNLOCK(); 1368 break; 1369 } 1370#endif 1371 1372 case BIOCGDLTLIST: 1373 BPF_LOCK(); 1374 if (d->bd_bif == NULL) 1375 error = EINVAL; 1376 else 1377 error = bpf_getdltlist(d, (struct bpf_dltlist *)addr); 1378 BPF_UNLOCK(); 1379 break; 1380 1381 /* 1382 * Set data link type. 1383 */ 1384 case BIOCSDLT: 1385 BPF_LOCK(); 1386 if (d->bd_bif == NULL) 1387 error = EINVAL; 1388 else 1389 error = bpf_setdlt(d, *(u_int *)addr); 1390 BPF_UNLOCK(); 1391 break; 1392 1393 /* 1394 * Get interface name. 1395 */ 1396 case BIOCGETIF: 1397 BPF_LOCK(); 1398 if (d->bd_bif == NULL) 1399 error = EINVAL; 1400 else { 1401 struct ifnet *const ifp = d->bd_bif->bif_ifp; 1402 struct ifreq *const ifr = (struct ifreq *)addr; 1403 1404 strlcpy(ifr->ifr_name, ifp->if_xname, 1405 sizeof(ifr->ifr_name)); 1406 } 1407 BPF_UNLOCK(); 1408 break; 1409 1410 /* 1411 * Set interface. 1412 */ 1413 case BIOCSETIF: 1414 BPF_LOCK(); 1415 error = bpf_setif(d, (struct ifreq *)addr); 1416 BPF_UNLOCK(); 1417 break; 1418 1419 /* 1420 * Set read timeout. 1421 */ 1422 case BIOCSRTIMEOUT: 1423#if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1424 case BIOCSRTIMEOUT32: 1425#endif 1426 { 1427 struct timeval *tv = (struct timeval *)addr; 1428#if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1429 struct timeval32 *tv32; 1430 struct timeval tv64; 1431 1432 if (cmd == BIOCSRTIMEOUT32) { 1433 tv32 = (struct timeval32 *)addr; 1434 tv = &tv64; 1435 tv->tv_sec = tv32->tv_sec; 1436 tv->tv_usec = tv32->tv_usec; 1437 } else 1438#endif 1439 tv = (struct timeval *)addr; 1440 1441 /* 1442 * Subtract 1 tick from tvtohz() since this isn't 1443 * a one-shot timer. 1444 */ 1445 if ((error = itimerfix(tv)) == 0) 1446 d->bd_rtout = tvtohz(tv) - 1; 1447 break; 1448 } 1449 1450 /* 1451 * Get read timeout. 1452 */ 1453 case BIOCGRTIMEOUT: 1454#if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1455 case BIOCGRTIMEOUT32: 1456#endif 1457 { 1458 struct timeval *tv; 1459#if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1460 struct timeval32 *tv32; 1461 struct timeval tv64; 1462 1463 if (cmd == BIOCGRTIMEOUT32) 1464 tv = &tv64; 1465 else 1466#endif 1467 tv = (struct timeval *)addr; 1468 1469 tv->tv_sec = d->bd_rtout / hz; 1470 tv->tv_usec = (d->bd_rtout % hz) * tick; 1471#if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1472 if (cmd == BIOCGRTIMEOUT32) { 1473 tv32 = (struct timeval32 *)addr; 1474 tv32->tv_sec = tv->tv_sec; 1475 tv32->tv_usec = tv->tv_usec; 1476 } 1477#endif 1478 1479 break; 1480 } 1481 1482 /* 1483 * Get packet stats. 1484 */ 1485 case BIOCGSTATS: 1486 { 1487 struct bpf_stat *bs = (struct bpf_stat *)addr; 1488 1489 /* XXXCSJP overflow */ 1490 bs->bs_recv = d->bd_rcount; 1491 bs->bs_drop = d->bd_dcount; 1492 break; 1493 } 1494 1495 /* 1496 * Set immediate mode. 1497 */ 1498 case BIOCIMMEDIATE: 1499 BPFD_LOCK(d); 1500 d->bd_immediate = *(u_int *)addr; 1501 BPFD_UNLOCK(d); 1502 break; 1503 1504 case BIOCVERSION: 1505 { 1506 struct bpf_version *bv = (struct bpf_version *)addr; 1507 1508 bv->bv_major = BPF_MAJOR_VERSION; 1509 bv->bv_minor = BPF_MINOR_VERSION; 1510 break; 1511 } 1512 1513 /* 1514 * Get "header already complete" flag 1515 */ 1516 case BIOCGHDRCMPLT: 1517 BPFD_LOCK(d); 1518 *(u_int *)addr = d->bd_hdrcmplt; 1519 BPFD_UNLOCK(d); 1520 break; 1521 1522 /* 1523 * Set "header already complete" flag 1524 */ 1525 case BIOCSHDRCMPLT: 1526 BPFD_LOCK(d); 1527 d->bd_hdrcmplt = *(u_int *)addr ? 1 : 0; 1528 BPFD_UNLOCK(d); 1529 break; 1530 1531 /* 1532 * Get packet direction flag 1533 */ 1534 case BIOCGDIRECTION: 1535 BPFD_LOCK(d); 1536 *(u_int *)addr = d->bd_direction; 1537 BPFD_UNLOCK(d); 1538 break; 1539 1540 /* 1541 * Set packet direction flag 1542 */ 1543 case BIOCSDIRECTION: 1544 { 1545 u_int direction; 1546 1547 direction = *(u_int *)addr; 1548 switch (direction) { 1549 case BPF_D_IN: 1550 case BPF_D_INOUT: 1551 case BPF_D_OUT: 1552 BPFD_LOCK(d); 1553 d->bd_direction = direction; 1554 BPFD_UNLOCK(d); 1555 break; 1556 default: 1557 error = EINVAL; 1558 } 1559 } 1560 break; 1561 1562 /* 1563 * Get packet timestamp format and resolution. 1564 */ 1565 case BIOCGTSTAMP: 1566 BPFD_LOCK(d); 1567 *(u_int *)addr = d->bd_tstamp; 1568 BPFD_UNLOCK(d); 1569 break; 1570 1571 /* 1572 * Set packet timestamp format and resolution. 1573 */ 1574 case BIOCSTSTAMP: 1575 { 1576 u_int func; 1577 1578 func = *(u_int *)addr; 1579 if (BPF_T_VALID(func)) 1580 d->bd_tstamp = func; 1581 else 1582 error = EINVAL; 1583 } 1584 break; 1585 1586 case BIOCFEEDBACK: 1587 BPFD_LOCK(d); 1588 d->bd_feedback = *(u_int *)addr; 1589 BPFD_UNLOCK(d); 1590 break; 1591 1592 case BIOCLOCK: 1593 BPFD_LOCK(d); 1594 d->bd_locked = 1; 1595 BPFD_UNLOCK(d); 1596 break; 1597 1598 case FIONBIO: /* Non-blocking I/O */ 1599 break; 1600 1601 case FIOASYNC: /* Send signal on receive packets */ 1602 BPFD_LOCK(d); 1603 d->bd_async = *(int *)addr; 1604 BPFD_UNLOCK(d); 1605 break; 1606 1607 case FIOSETOWN: 1608 /* 1609 * XXX: Add some sort of locking here? 1610 * fsetown() can sleep. 1611 */ 1612 error = fsetown(*(int *)addr, &d->bd_sigio); 1613 break; 1614 1615 case FIOGETOWN: 1616 BPFD_LOCK(d); 1617 *(int *)addr = fgetown(&d->bd_sigio); 1618 BPFD_UNLOCK(d); 1619 break; 1620 1621 /* This is deprecated, FIOSETOWN should be used instead. */ 1622 case TIOCSPGRP: 1623 error = fsetown(-(*(int *)addr), &d->bd_sigio); 1624 break; 1625 1626 /* This is deprecated, FIOGETOWN should be used instead. */ 1627 case TIOCGPGRP: 1628 *(int *)addr = -fgetown(&d->bd_sigio); 1629 break; 1630 1631 case BIOCSRSIG: /* Set receive signal */ 1632 { 1633 u_int sig; 1634 1635 sig = *(u_int *)addr; 1636 1637 if (sig >= NSIG) 1638 error = EINVAL; 1639 else { 1640 BPFD_LOCK(d); 1641 d->bd_sig = sig; 1642 BPFD_UNLOCK(d); 1643 } 1644 break; 1645 } 1646 case BIOCGRSIG: 1647 BPFD_LOCK(d); 1648 *(u_int *)addr = d->bd_sig; 1649 BPFD_UNLOCK(d); 1650 break; 1651 1652 case BIOCGETBUFMODE: 1653 BPFD_LOCK(d); 1654 *(u_int *)addr = d->bd_bufmode; 1655 BPFD_UNLOCK(d); 1656 break; 1657 1658 case BIOCSETBUFMODE: 1659 /* 1660 * Allow the buffering mode to be changed as long as we 1661 * haven't yet committed to a particular mode. Our 1662 * definition of commitment, for now, is whether or not a 1663 * buffer has been allocated or an interface attached, since 1664 * that's the point where things get tricky. 1665 */ 1666 switch (*(u_int *)addr) { 1667 case BPF_BUFMODE_BUFFER: 1668 break; 1669 1670 case BPF_BUFMODE_ZBUF: 1671 if (bpf_zerocopy_enable) 1672 break; 1673 /* FALLSTHROUGH */ 1674 1675 default: 1676 CURVNET_RESTORE(); 1677 return (EINVAL); 1678 } 1679 1680 BPFD_LOCK(d); 1681 if (d->bd_sbuf != NULL || d->bd_hbuf != NULL || 1682 d->bd_fbuf != NULL || d->bd_bif != NULL) { 1683 BPFD_UNLOCK(d); 1684 CURVNET_RESTORE(); 1685 return (EBUSY); 1686 } 1687 d->bd_bufmode = *(u_int *)addr; 1688 BPFD_UNLOCK(d); 1689 break; 1690 1691 case BIOCGETZMAX: 1692 error = bpf_ioctl_getzmax(td, d, (size_t *)addr); 1693 break; 1694 1695 case BIOCSETZBUF: 1696 error = bpf_ioctl_setzbuf(td, d, (struct bpf_zbuf *)addr); 1697 break; 1698 1699 case BIOCROTZBUF: 1700 error = bpf_ioctl_rotzbuf(td, d, (struct bpf_zbuf *)addr); 1701 break; 1702 } 1703 CURVNET_RESTORE(); 1704 return (error); 1705} 1706 1707/* 1708 * Set d's packet filter program to fp. If this file already has a filter, 1709 * free it and replace it. Returns EINVAL for bogus requests. 1710 * 1711 * Note we need global lock here to serialize bpf_setf() and bpf_setif() calls 1712 * since reading d->bd_bif can't be protected by d or interface lock due to 1713 * lock order. 1714 * 1715 * Additionally, we have to acquire interface write lock due to bpf_mtap() uses 1716 * interface read lock to read all filers. 1717 * 1718 */ 1719static int 1720bpf_setf(struct bpf_d *d, struct bpf_program *fp, u_long cmd) 1721{ 1722#ifdef COMPAT_FREEBSD32 1723 struct bpf_program fp_swab; 1724 struct bpf_program32 *fp32; 1725#endif 1726 struct bpf_insn *fcode, *old; 1727#ifdef BPF_JITTER 1728 bpf_jit_filter *jfunc, *ofunc; 1729#endif 1730 size_t size; 1731 u_int flen; 1732 int need_upgrade; 1733 1734#ifdef COMPAT_FREEBSD32 1735 switch (cmd) { 1736 case BIOCSETF32: 1737 case BIOCSETWF32: 1738 case BIOCSETFNR32: 1739 fp32 = (struct bpf_program32 *)fp; 1740 fp_swab.bf_len = fp32->bf_len; 1741 fp_swab.bf_insns = (struct bpf_insn *)(uintptr_t)fp32->bf_insns; 1742 fp = &fp_swab; 1743 switch (cmd) { 1744 case BIOCSETF32: 1745 cmd = BIOCSETF; 1746 break; 1747 case BIOCSETWF32: 1748 cmd = BIOCSETWF; 1749 break; 1750 } 1751 break; 1752 } 1753#endif 1754 1755 fcode = NULL; 1756#ifdef BPF_JITTER 1757 jfunc = ofunc = NULL; 1758#endif 1759 need_upgrade = 0; 1760 1761 /* 1762 * Check new filter validness before acquiring any locks. 1763 * Allocate memory for new filter, if needed. 1764 */ 1765 flen = fp->bf_len; 1766 if (flen > bpf_maxinsns || (fp->bf_insns == NULL && flen != 0)) 1767 return (EINVAL); 1768 size = flen * sizeof(*fp->bf_insns); 1769 if (size > 0) { 1770 /* We're setting up new filter. Copy and check actual data. */ 1771 fcode = malloc(size, M_BPF, M_WAITOK); 1772 if (copyin(fp->bf_insns, fcode, size) != 0 || 1773 !bpf_validate(fcode, flen)) { 1774 free(fcode, M_BPF); 1775 return (EINVAL); 1776 } 1777#ifdef BPF_JITTER 1778 /* Filter is copied inside fcode and is perfectly valid. */ 1779 jfunc = bpf_jitter(fcode, flen); 1780#endif 1781 } 1782 1783 BPF_LOCK(); 1784 1785 /* 1786 * Set up new filter. 1787 * Protect filter change by interface lock. 1788 * Additionally, we are protected by global lock here. 1789 */ 1790 if (d->bd_bif != NULL) 1791 BPFIF_WLOCK(d->bd_bif); 1792 BPFD_LOCK(d); 1793 if (cmd == BIOCSETWF) { 1794 old = d->bd_wfilter; 1795 d->bd_wfilter = fcode; 1796 } else { 1797 old = d->bd_rfilter; 1798 d->bd_rfilter = fcode; 1799#ifdef BPF_JITTER 1800 ofunc = d->bd_bfilter; 1801 d->bd_bfilter = jfunc; 1802#endif 1803 if (cmd == BIOCSETF) 1804 reset_d(d); 1805 1806 if (fcode != NULL) { 1807 /* 1808 * Do not require upgrade by first BIOCSETF 1809 * (used to set snaplen) by pcap_open_live(). 1810 */ 1811 if (d->bd_writer != 0 && --d->bd_writer == 0) 1812 need_upgrade = 1; 1813 CTR4(KTR_NET, "%s: filter function set by pid %d, " 1814 "bd_writer counter %d, need_upgrade %d", 1815 __func__, d->bd_pid, d->bd_writer, need_upgrade); 1816 } 1817 } 1818 BPFD_UNLOCK(d); 1819 if (d->bd_bif != NULL) 1820 BPFIF_WUNLOCK(d->bd_bif); 1821 if (old != NULL) 1822 free(old, M_BPF); 1823#ifdef BPF_JITTER 1824 if (ofunc != NULL) 1825 bpf_destroy_jit_filter(ofunc); 1826#endif 1827 1828 /* Move d to active readers list. */ 1829 if (need_upgrade) 1830 bpf_upgraded(d); 1831 1832 BPF_UNLOCK(); 1833 return (0); 1834} 1835 1836/* 1837 * Detach a file from its current interface (if attached at all) and attach 1838 * to the interface indicated by the name stored in ifr. 1839 * Return an errno or 0. 1840 */ 1841static int 1842bpf_setif(struct bpf_d *d, struct ifreq *ifr) 1843{ 1844 struct bpf_if *bp; 1845 struct ifnet *theywant; 1846 1847 BPF_LOCK_ASSERT(); 1848 1849 theywant = ifunit(ifr->ifr_name); 1850 if (theywant == NULL || theywant->if_bpf == NULL) 1851 return (ENXIO); 1852 1853 bp = theywant->if_bpf; 1854 1855 /* Check if interface is not being detached from BPF */ 1856 BPFIF_RLOCK(bp); 1857 if (bp->flags & BPFIF_FLAG_DYING) { 1858 BPFIF_RUNLOCK(bp); 1859 return (ENXIO); 1860 } 1861 BPFIF_RUNLOCK(bp); 1862 1863 /* 1864 * Behavior here depends on the buffering model. If we're using 1865 * kernel memory buffers, then we can allocate them here. If we're 1866 * using zero-copy, then the user process must have registered 1867 * buffers by the time we get here. If not, return an error. 1868 */ 1869 switch (d->bd_bufmode) { 1870 case BPF_BUFMODE_BUFFER: 1871 case BPF_BUFMODE_ZBUF: 1872 if (d->bd_sbuf == NULL) 1873 return (EINVAL); 1874 break; 1875 1876 default: 1877 panic("bpf_setif: bufmode %d", d->bd_bufmode); 1878 } 1879 if (bp != d->bd_bif) 1880 bpf_attachd(d, bp); 1881 BPFD_LOCK(d); 1882 reset_d(d); 1883 BPFD_UNLOCK(d); 1884 return (0); 1885} 1886 1887/* 1888 * Support for select() and poll() system calls 1889 * 1890 * Return true iff the specific operation will not block indefinitely. 1891 * Otherwise, return false but make a note that a selwakeup() must be done. 1892 */ 1893static int 1894bpfpoll(struct cdev *dev, int events, struct thread *td) 1895{ 1896 struct bpf_d *d; 1897 int revents; 1898 1899 if (devfs_get_cdevpriv((void **)&d) != 0 || d->bd_bif == NULL) 1900 return (events & 1901 (POLLHUP|POLLIN|POLLRDNORM|POLLOUT|POLLWRNORM)); 1902 1903 /* 1904 * Refresh PID associated with this descriptor. 1905 */ 1906 revents = events & (POLLOUT | POLLWRNORM); 1907 BPFD_LOCK(d); 1908 BPF_PID_REFRESH(d, td); 1909 if (events & (POLLIN | POLLRDNORM)) { 1910 if (bpf_ready(d)) 1911 revents |= events & (POLLIN | POLLRDNORM); 1912 else { 1913 selrecord(td, &d->bd_sel); 1914 /* Start the read timeout if necessary. */ 1915 if (d->bd_rtout > 0 && d->bd_state == BPF_IDLE) { 1916 callout_reset(&d->bd_callout, d->bd_rtout, 1917 bpf_timed_out, d); 1918 d->bd_state = BPF_WAITING; 1919 } 1920 } 1921 } 1922 BPFD_UNLOCK(d); 1923 return (revents); 1924} 1925 1926/* 1927 * Support for kevent() system call. Register EVFILT_READ filters and 1928 * reject all others. 1929 */ 1930int 1931bpfkqfilter(struct cdev *dev, struct knote *kn) 1932{ 1933 struct bpf_d *d; 1934 1935 if (devfs_get_cdevpriv((void **)&d) != 0 || 1936 kn->kn_filter != EVFILT_READ) 1937 return (1); 1938 1939 /* 1940 * Refresh PID associated with this descriptor. 1941 */ 1942 BPFD_LOCK(d); 1943 BPF_PID_REFRESH_CUR(d); 1944 kn->kn_fop = &bpfread_filtops; 1945 kn->kn_hook = d; 1946 knlist_add(&d->bd_sel.si_note, kn, 1); 1947 BPFD_UNLOCK(d); 1948 1949 return (0); 1950} 1951 1952static void 1953filt_bpfdetach(struct knote *kn) 1954{ 1955 struct bpf_d *d = (struct bpf_d *)kn->kn_hook; 1956 1957 knlist_remove(&d->bd_sel.si_note, kn, 0); 1958} 1959 1960static int 1961filt_bpfread(struct knote *kn, long hint) 1962{ 1963 struct bpf_d *d = (struct bpf_d *)kn->kn_hook; 1964 int ready; 1965 1966 BPFD_LOCK_ASSERT(d); 1967 ready = bpf_ready(d); 1968 if (ready) { 1969 kn->kn_data = d->bd_slen; 1970 if (d->bd_hbuf) 1971 kn->kn_data += d->bd_hlen; 1972 } else if (d->bd_rtout > 0 && d->bd_state == BPF_IDLE) { 1973 callout_reset(&d->bd_callout, d->bd_rtout, 1974 bpf_timed_out, d); 1975 d->bd_state = BPF_WAITING; 1976 } 1977 1978 return (ready); 1979} 1980 1981#define BPF_TSTAMP_NONE 0 1982#define BPF_TSTAMP_FAST 1 1983#define BPF_TSTAMP_NORMAL 2 1984#define BPF_TSTAMP_EXTERN 3 1985 1986static int 1987bpf_ts_quality(int tstype) 1988{ 1989 1990 if (tstype == BPF_T_NONE) 1991 return (BPF_TSTAMP_NONE); 1992 if ((tstype & BPF_T_FAST) != 0) 1993 return (BPF_TSTAMP_FAST); 1994 1995 return (BPF_TSTAMP_NORMAL); 1996} 1997 1998static int 1999bpf_gettime(struct bintime *bt, int tstype, struct mbuf *m) 2000{ 2001 struct m_tag *tag; 2002 int quality; 2003 2004 quality = bpf_ts_quality(tstype); 2005 if (quality == BPF_TSTAMP_NONE) 2006 return (quality); 2007 2008 if (m != NULL) { 2009 tag = m_tag_locate(m, MTAG_BPF, MTAG_BPF_TIMESTAMP, NULL); 2010 if (tag != NULL) { 2011 *bt = *(struct bintime *)(tag + 1); 2012 return (BPF_TSTAMP_EXTERN); 2013 } 2014 } 2015 if (quality == BPF_TSTAMP_NORMAL) 2016 binuptime(bt); 2017 else 2018 getbinuptime(bt); 2019 2020 return (quality); 2021} 2022 2023/* 2024 * Incoming linkage from device drivers. Process the packet pkt, of length 2025 * pktlen, which is stored in a contiguous buffer. The packet is parsed 2026 * by each process' filter, and if accepted, stashed into the corresponding 2027 * buffer. 2028 */ 2029void 2030bpf_tap(struct bpf_if *bp, u_char *pkt, u_int pktlen) 2031{ 2032 struct bintime bt; 2033 struct bpf_d *d; 2034#ifdef BPF_JITTER 2035 bpf_jit_filter *bf; 2036#endif 2037 u_int slen; 2038 int gottime; 2039 2040 gottime = BPF_TSTAMP_NONE; 2041 2042 BPFIF_RLOCK(bp); 2043 2044 LIST_FOREACH(d, &bp->bif_dlist, bd_next) { 2045 /* 2046 * We are not using any locks for d here because: 2047 * 1) any filter change is protected by interface 2048 * write lock 2049 * 2) destroying/detaching d is protected by interface 2050 * write lock, too 2051 */ 2052 2053 /* XXX: Do not protect counter for the sake of performance. */ 2054 ++d->bd_rcount; 2055 /* 2056 * NB: We dont call BPF_CHECK_DIRECTION() here since there is no 2057 * way for the caller to indiciate to us whether this packet 2058 * is inbound or outbound. In the bpf_mtap() routines, we use 2059 * the interface pointers on the mbuf to figure it out. 2060 */ 2061#ifdef BPF_JITTER 2062 bf = bpf_jitter_enable != 0 ? d->bd_bfilter : NULL; 2063 if (bf != NULL) 2064 slen = (*(bf->func))(pkt, pktlen, pktlen); 2065 else 2066#endif 2067 slen = bpf_filter(d->bd_rfilter, pkt, pktlen, pktlen); 2068 if (slen != 0) { 2069 /* 2070 * Filter matches. Let's to acquire write lock. 2071 */ 2072 BPFD_LOCK(d); 2073 2074 d->bd_fcount++; 2075 if (gottime < bpf_ts_quality(d->bd_tstamp)) 2076 gottime = bpf_gettime(&bt, d->bd_tstamp, NULL); 2077#ifdef MAC 2078 if (mac_bpfdesc_check_receive(d, bp->bif_ifp) == 0) 2079#endif 2080 catchpacket(d, pkt, pktlen, slen, 2081 bpf_append_bytes, &bt); 2082 BPFD_UNLOCK(d); 2083 } 2084 } 2085 BPFIF_RUNLOCK(bp); 2086} 2087 2088#define BPF_CHECK_DIRECTION(d, r, i) \ 2089 (((d)->bd_direction == BPF_D_IN && (r) != (i)) || \ 2090 ((d)->bd_direction == BPF_D_OUT && (r) == (i))) 2091 2092/* 2093 * Incoming linkage from device drivers, when packet is in an mbuf chain. 2094 * Locking model is explained in bpf_tap(). 2095 */ 2096void 2097bpf_mtap(struct bpf_if *bp, struct mbuf *m) 2098{ 2099 struct bintime bt; 2100 struct bpf_d *d; 2101#ifdef BPF_JITTER 2102 bpf_jit_filter *bf; 2103#endif 2104 u_int pktlen, slen; 2105 int gottime; 2106 2107 /* Skip outgoing duplicate packets. */ 2108 if ((m->m_flags & M_PROMISC) != 0 && m->m_pkthdr.rcvif == NULL) { 2109 m->m_flags &= ~M_PROMISC; 2110 return; 2111 } 2112 2113 pktlen = m_length(m, NULL); 2114 gottime = BPF_TSTAMP_NONE; 2115 2116 BPFIF_RLOCK(bp); 2117 2118 LIST_FOREACH(d, &bp->bif_dlist, bd_next) { 2119 if (BPF_CHECK_DIRECTION(d, m->m_pkthdr.rcvif, bp->bif_ifp)) 2120 continue; 2121 ++d->bd_rcount; 2122#ifdef BPF_JITTER 2123 bf = bpf_jitter_enable != 0 ? d->bd_bfilter : NULL; 2124 /* XXX We cannot handle multiple mbufs. */ 2125 if (bf != NULL && m->m_next == NULL) 2126 slen = (*(bf->func))(mtod(m, u_char *), pktlen, pktlen); 2127 else 2128#endif 2129 slen = bpf_filter(d->bd_rfilter, (u_char *)m, pktlen, 0); 2130 if (slen != 0) { 2131 BPFD_LOCK(d); 2132 2133 d->bd_fcount++; 2134 if (gottime < bpf_ts_quality(d->bd_tstamp)) 2135 gottime = bpf_gettime(&bt, d->bd_tstamp, m); 2136#ifdef MAC 2137 if (mac_bpfdesc_check_receive(d, bp->bif_ifp) == 0) 2138#endif 2139 catchpacket(d, (u_char *)m, pktlen, slen, 2140 bpf_append_mbuf, &bt); 2141 BPFD_UNLOCK(d); 2142 } 2143 } 2144 BPFIF_RUNLOCK(bp); 2145} 2146 2147/* 2148 * Incoming linkage from device drivers, when packet is in 2149 * an mbuf chain and to be prepended by a contiguous header. 2150 */ 2151void 2152bpf_mtap2(struct bpf_if *bp, void *data, u_int dlen, struct mbuf *m) 2153{ 2154 struct bintime bt; 2155 struct mbuf mb; 2156 struct bpf_d *d; 2157 u_int pktlen, slen; 2158 int gottime; 2159 2160 /* Skip outgoing duplicate packets. */ 2161 if ((m->m_flags & M_PROMISC) != 0 && m->m_pkthdr.rcvif == NULL) { 2162 m->m_flags &= ~M_PROMISC; 2163 return; 2164 } 2165 2166 pktlen = m_length(m, NULL); 2167 /* 2168 * Craft on-stack mbuf suitable for passing to bpf_filter. 2169 * Note that we cut corners here; we only setup what's 2170 * absolutely needed--this mbuf should never go anywhere else. 2171 */ 2172 mb.m_next = m; 2173 mb.m_data = data; 2174 mb.m_len = dlen; 2175 pktlen += dlen; 2176 2177 gottime = BPF_TSTAMP_NONE; 2178 2179 BPFIF_RLOCK(bp); 2180 2181 LIST_FOREACH(d, &bp->bif_dlist, bd_next) { 2182 if (BPF_CHECK_DIRECTION(d, m->m_pkthdr.rcvif, bp->bif_ifp)) 2183 continue; 2184 ++d->bd_rcount; 2185 slen = bpf_filter(d->bd_rfilter, (u_char *)&mb, pktlen, 0); 2186 if (slen != 0) { 2187 BPFD_LOCK(d); 2188 2189 d->bd_fcount++; 2190 if (gottime < bpf_ts_quality(d->bd_tstamp)) 2191 gottime = bpf_gettime(&bt, d->bd_tstamp, m); 2192#ifdef MAC 2193 if (mac_bpfdesc_check_receive(d, bp->bif_ifp) == 0) 2194#endif 2195 catchpacket(d, (u_char *)&mb, pktlen, slen, 2196 bpf_append_mbuf, &bt); 2197 BPFD_UNLOCK(d); 2198 } 2199 } 2200 BPFIF_RUNLOCK(bp); 2201} 2202 2203#undef BPF_CHECK_DIRECTION 2204 2205#undef BPF_TSTAMP_NONE 2206#undef BPF_TSTAMP_FAST 2207#undef BPF_TSTAMP_NORMAL 2208#undef BPF_TSTAMP_EXTERN 2209 2210static int 2211bpf_hdrlen(struct bpf_d *d) 2212{ 2213 int hdrlen; 2214 2215 hdrlen = d->bd_bif->bif_hdrlen; 2216#ifndef BURN_BRIDGES 2217 if (d->bd_tstamp == BPF_T_NONE || 2218 BPF_T_FORMAT(d->bd_tstamp) == BPF_T_MICROTIME) 2219#ifdef COMPAT_FREEBSD32 2220 if (d->bd_compat32) 2221 hdrlen += SIZEOF_BPF_HDR(struct bpf_hdr32); 2222 else 2223#endif 2224 hdrlen += SIZEOF_BPF_HDR(struct bpf_hdr); 2225 else 2226#endif 2227 hdrlen += SIZEOF_BPF_HDR(struct bpf_xhdr); 2228#ifdef COMPAT_FREEBSD32 2229 if (d->bd_compat32) 2230 hdrlen = BPF_WORDALIGN32(hdrlen); 2231 else 2232#endif 2233 hdrlen = BPF_WORDALIGN(hdrlen); 2234 2235 return (hdrlen - d->bd_bif->bif_hdrlen); 2236} 2237 2238static void 2239bpf_bintime2ts(struct bintime *bt, struct bpf_ts *ts, int tstype) 2240{ 2241 struct bintime bt2; 2242 struct timeval tsm; 2243 struct timespec tsn; 2244 2245 if ((tstype & BPF_T_MONOTONIC) == 0) { 2246 bt2 = *bt; 2247 bintime_add(&bt2, &boottimebin); 2248 bt = &bt2; 2249 } 2250 switch (BPF_T_FORMAT(tstype)) { 2251 case BPF_T_MICROTIME: 2252 bintime2timeval(bt, &tsm); 2253 ts->bt_sec = tsm.tv_sec; 2254 ts->bt_frac = tsm.tv_usec; 2255 break; 2256 case BPF_T_NANOTIME: 2257 bintime2timespec(bt, &tsn); 2258 ts->bt_sec = tsn.tv_sec; 2259 ts->bt_frac = tsn.tv_nsec; 2260 break; 2261 case BPF_T_BINTIME: 2262 ts->bt_sec = bt->sec; 2263 ts->bt_frac = bt->frac; 2264 break; 2265 } 2266} 2267 2268/* 2269 * Move the packet data from interface memory (pkt) into the 2270 * store buffer. "cpfn" is the routine called to do the actual data 2271 * transfer. bcopy is passed in to copy contiguous chunks, while 2272 * bpf_append_mbuf is passed in to copy mbuf chains. In the latter case, 2273 * pkt is really an mbuf. 2274 */ 2275static void 2276catchpacket(struct bpf_d *d, u_char *pkt, u_int pktlen, u_int snaplen, 2277 void (*cpfn)(struct bpf_d *, caddr_t, u_int, void *, u_int), 2278 struct bintime *bt) 2279{ 2280 struct bpf_xhdr hdr; 2281#ifndef BURN_BRIDGES 2282 struct bpf_hdr hdr_old; 2283#ifdef COMPAT_FREEBSD32 2284 struct bpf_hdr32 hdr32_old; 2285#endif 2286#endif 2287 int caplen, curlen, hdrlen, totlen; 2288 int do_wakeup = 0; 2289 int do_timestamp; 2290 int tstype; 2291 2292 BPFD_LOCK_ASSERT(d); 2293 2294 /* 2295 * Detect whether user space has released a buffer back to us, and if 2296 * so, move it from being a hold buffer to a free buffer. This may 2297 * not be the best place to do it (for example, we might only want to 2298 * run this check if we need the space), but for now it's a reliable 2299 * spot to do it. 2300 */ 2301 if (d->bd_fbuf == NULL && bpf_canfreebuf(d)) { 2302 d->bd_fbuf = d->bd_hbuf; 2303 d->bd_hbuf = NULL; 2304 d->bd_hlen = 0; 2305 bpf_buf_reclaimed(d); 2306 } 2307 2308 /* 2309 * Figure out how many bytes to move. If the packet is 2310 * greater or equal to the snapshot length, transfer that 2311 * much. Otherwise, transfer the whole packet (unless 2312 * we hit the buffer size limit). 2313 */ 2314 hdrlen = bpf_hdrlen(d); 2315 totlen = hdrlen + min(snaplen, pktlen); 2316 if (totlen > d->bd_bufsize) 2317 totlen = d->bd_bufsize; 2318 2319 /* 2320 * Round up the end of the previous packet to the next longword. 2321 * 2322 * Drop the packet if there's no room and no hope of room 2323 * If the packet would overflow the storage buffer or the storage 2324 * buffer is considered immutable by the buffer model, try to rotate 2325 * the buffer and wakeup pending processes. 2326 */ 2327#ifdef COMPAT_FREEBSD32 2328 if (d->bd_compat32) 2329 curlen = BPF_WORDALIGN32(d->bd_slen); 2330 else 2331#endif 2332 curlen = BPF_WORDALIGN(d->bd_slen); 2333 if (curlen + totlen > d->bd_bufsize || !bpf_canwritebuf(d)) { 2334 if (d->bd_fbuf == NULL) { 2335 /* 2336 * There's no room in the store buffer, and no 2337 * prospect of room, so drop the packet. Notify the 2338 * buffer model. 2339 */ 2340 bpf_buffull(d); 2341 ++d->bd_dcount; 2342 return; 2343 } 2344 ROTATE_BUFFERS(d); 2345 do_wakeup = 1; 2346 curlen = 0; 2347 } else if (d->bd_immediate || d->bd_state == BPF_TIMED_OUT) 2348 /* 2349 * Immediate mode is set, or the read timeout has already 2350 * expired during a select call. A packet arrived, so the 2351 * reader should be woken up. 2352 */ 2353 do_wakeup = 1; 2354 caplen = totlen - hdrlen; 2355 tstype = d->bd_tstamp; 2356 do_timestamp = tstype != BPF_T_NONE; 2357#ifndef BURN_BRIDGES 2358 if (tstype == BPF_T_NONE || BPF_T_FORMAT(tstype) == BPF_T_MICROTIME) { 2359 struct bpf_ts ts; 2360 if (do_timestamp) 2361 bpf_bintime2ts(bt, &ts, tstype); 2362#ifdef COMPAT_FREEBSD32 2363 if (d->bd_compat32) { 2364 bzero(&hdr32_old, sizeof(hdr32_old)); 2365 if (do_timestamp) { 2366 hdr32_old.bh_tstamp.tv_sec = ts.bt_sec; 2367 hdr32_old.bh_tstamp.tv_usec = ts.bt_frac; 2368 } 2369 hdr32_old.bh_datalen = pktlen; 2370 hdr32_old.bh_hdrlen = hdrlen; 2371 hdr32_old.bh_caplen = caplen; 2372 bpf_append_bytes(d, d->bd_sbuf, curlen, &hdr32_old, 2373 sizeof(hdr32_old)); 2374 goto copy; 2375 } 2376#endif 2377 bzero(&hdr_old, sizeof(hdr_old)); 2378 if (do_timestamp) { 2379 hdr_old.bh_tstamp.tv_sec = ts.bt_sec; 2380 hdr_old.bh_tstamp.tv_usec = ts.bt_frac; 2381 } 2382 hdr_old.bh_datalen = pktlen; 2383 hdr_old.bh_hdrlen = hdrlen; 2384 hdr_old.bh_caplen = caplen; 2385 bpf_append_bytes(d, d->bd_sbuf, curlen, &hdr_old, 2386 sizeof(hdr_old)); 2387 goto copy; 2388 } 2389#endif 2390 2391 /* 2392 * Append the bpf header. Note we append the actual header size, but 2393 * move forward the length of the header plus padding. 2394 */ 2395 bzero(&hdr, sizeof(hdr)); 2396 if (do_timestamp) 2397 bpf_bintime2ts(bt, &hdr.bh_tstamp, tstype); 2398 hdr.bh_datalen = pktlen; 2399 hdr.bh_hdrlen = hdrlen; 2400 hdr.bh_caplen = caplen; 2401 bpf_append_bytes(d, d->bd_sbuf, curlen, &hdr, sizeof(hdr)); 2402 2403 /* 2404 * Copy the packet data into the store buffer and update its length. 2405 */ 2406#ifndef BURN_BRIDGES 2407copy: 2408#endif 2409 (*cpfn)(d, d->bd_sbuf, curlen + hdrlen, pkt, caplen); 2410 d->bd_slen = curlen + totlen; 2411 2412 if (do_wakeup) 2413 bpf_wakeup(d); 2414} 2415 2416/* 2417 * Free buffers currently in use by a descriptor. 2418 * Called on close. 2419 */ 2420static void 2421bpf_freed(struct bpf_d *d) 2422{ 2423 2424 /* 2425 * We don't need to lock out interrupts since this descriptor has 2426 * been detached from its interface and it yet hasn't been marked 2427 * free. 2428 */ 2429 bpf_free(d); 2430 if (d->bd_rfilter != NULL) { 2431 free((caddr_t)d->bd_rfilter, M_BPF); 2432#ifdef BPF_JITTER 2433 if (d->bd_bfilter != NULL) 2434 bpf_destroy_jit_filter(d->bd_bfilter); 2435#endif 2436 } 2437 if (d->bd_wfilter != NULL) 2438 free((caddr_t)d->bd_wfilter, M_BPF); 2439 mtx_destroy(&d->bd_lock); 2440} 2441 2442/* 2443 * Attach an interface to bpf. dlt is the link layer type; hdrlen is the 2444 * fixed size of the link header (variable length headers not yet supported). 2445 */ 2446void 2447bpfattach(struct ifnet *ifp, u_int dlt, u_int hdrlen) 2448{ 2449 2450 bpfattach2(ifp, dlt, hdrlen, &ifp->if_bpf); 2451} 2452 2453/* 2454 * Attach an interface to bpf. ifp is a pointer to the structure 2455 * defining the interface to be attached, dlt is the link layer type, 2456 * and hdrlen is the fixed size of the link header (variable length 2457 * headers are not yet supporrted). 2458 */ 2459void 2460bpfattach2(struct ifnet *ifp, u_int dlt, u_int hdrlen, struct bpf_if **driverp) 2461{ 2462 struct bpf_if *bp; 2463 2464 bp = malloc(sizeof(*bp), M_BPF, M_NOWAIT | M_ZERO); 2465 if (bp == NULL) 2466 panic("bpfattach"); 2467 2468 LIST_INIT(&bp->bif_dlist); 2469 LIST_INIT(&bp->bif_wlist); 2470 bp->bif_ifp = ifp; 2471 bp->bif_dlt = dlt; 2472 rw_init(&bp->bif_lock, "bpf interface lock"); 2473 KASSERT(*driverp == NULL, ("bpfattach2: driverp already initialized")); 2474 *driverp = bp; 2475 2476 BPF_LOCK(); 2477 LIST_INSERT_HEAD(&bpf_iflist, bp, bif_next); 2478 BPF_UNLOCK(); 2479 2480 bp->bif_hdrlen = hdrlen; 2481 2482 if (bootverbose) 2483 if_printf(ifp, "bpf attached\n"); 2484} 2485 2486/* 2487 * Detach bpf from an interface. This involves detaching each descriptor 2488 * associated with the interface. Notify each descriptor as it's detached 2489 * so that any sleepers wake up and get ENXIO. 2490 */ 2491void 2492bpfdetach(struct ifnet *ifp) 2493{ 2494 struct bpf_if *bp, *bp_temp; 2495 struct bpf_d *d; 2496 int ndetached; 2497 2498 ndetached = 0; 2499 2500 BPF_LOCK(); 2501 /* Find all bpf_if struct's which reference ifp and detach them. */ 2502 LIST_FOREACH_SAFE(bp, &bpf_iflist, bif_next, bp_temp) { 2503 if (ifp != bp->bif_ifp) 2504 continue; 2505 2506 LIST_REMOVE(bp, bif_next); 2507 /* Add to to-be-freed list */ 2508 LIST_INSERT_HEAD(&bpf_freelist, bp, bif_next); 2509 2510 ndetached++; 2511 /* 2512 * Delay freeing bp till interface is detached 2513 * and all routes through this interface are removed. 2514 * Mark bp as detached to restrict new consumers. 2515 */ 2516 BPFIF_WLOCK(bp); 2517 bp->flags |= BPFIF_FLAG_DYING; 2518 BPFIF_WUNLOCK(bp); 2519 2520 CTR4(KTR_NET, "%s: sheduling free for encap %d (%p) for if %p", 2521 __func__, bp->bif_dlt, bp, ifp); 2522 2523 /* Free common descriptors */ 2524 while ((d = LIST_FIRST(&bp->bif_dlist)) != NULL) { 2525 bpf_detachd_locked(d); 2526 BPFD_LOCK(d); 2527 bpf_wakeup(d); 2528 BPFD_UNLOCK(d); 2529 } 2530 2531 /* Free writer-only descriptors */ 2532 while ((d = LIST_FIRST(&bp->bif_wlist)) != NULL) { 2533 bpf_detachd_locked(d); 2534 BPFD_LOCK(d); 2535 bpf_wakeup(d); 2536 BPFD_UNLOCK(d); 2537 } 2538 } 2539 BPF_UNLOCK(); 2540 2541#ifdef INVARIANTS 2542 if (ndetached == 0) 2543 printf("bpfdetach: %s was not attached\n", ifp->if_xname); 2544#endif 2545} 2546 2547/* 2548 * Interface departure handler. 2549 * Note departure event does not guarantee interface is going down. 2550 * Interface renaming is currently done via departure/arrival event set. 2551 * 2552 * Departure handled is called after all routes pointing to 2553 * given interface are removed and interface is in down state 2554 * restricting any packets to be sent/received. We assume it is now safe 2555 * to free data allocated by BPF. 2556 */ 2557static void 2558bpf_ifdetach(void *arg __unused, struct ifnet *ifp) 2559{ 2560 struct bpf_if *bp, *bp_temp; 2561 int nmatched = 0; 2562 2563 BPF_LOCK(); 2564 /* 2565 * Find matching entries in free list. 2566 * Nothing should be found if bpfdetach() was not called. 2567 */ 2568 LIST_FOREACH_SAFE(bp, &bpf_freelist, bif_next, bp_temp) { 2569 if (ifp != bp->bif_ifp) 2570 continue; 2571 2572 CTR3(KTR_NET, "%s: freeing BPF instance %p for interface %p", 2573 __func__, bp, ifp); 2574 2575 LIST_REMOVE(bp, bif_next); 2576 2577 rw_destroy(&bp->bif_lock); 2578 free(bp, M_BPF); 2579 2580 nmatched++; 2581 } 2582 BPF_UNLOCK(); 2583 2584 /* 2585 * Note that we cannot zero other pointers to 2586 * custom DLTs possibly used by given interface. 2587 */ 2588 if (nmatched != 0) 2589 ifp->if_bpf = NULL; 2590} 2591 2592/* 2593 * Get a list of available data link type of the interface. 2594 */ 2595static int 2596bpf_getdltlist(struct bpf_d *d, struct bpf_dltlist *bfl) 2597{ 2598 int n, error; 2599 struct ifnet *ifp; 2600 struct bpf_if *bp; 2601 2602 BPF_LOCK_ASSERT(); 2603 2604 ifp = d->bd_bif->bif_ifp; 2605 n = 0; 2606 error = 0; 2607 LIST_FOREACH(bp, &bpf_iflist, bif_next) { 2608 if (bp->bif_ifp != ifp) 2609 continue; 2610 if (bfl->bfl_list != NULL) { 2611 if (n >= bfl->bfl_len) 2612 return (ENOMEM); 2613 error = copyout(&bp->bif_dlt, 2614 bfl->bfl_list + n, sizeof(u_int)); 2615 } 2616 n++; 2617 } 2618 bfl->bfl_len = n; 2619 return (error); 2620} 2621 2622/* 2623 * Set the data link type of a BPF instance. 2624 */ 2625static int 2626bpf_setdlt(struct bpf_d *d, u_int dlt) 2627{ 2628 int error, opromisc; 2629 struct ifnet *ifp; 2630 struct bpf_if *bp; 2631 2632 BPF_LOCK_ASSERT(); 2633 2634 if (d->bd_bif->bif_dlt == dlt) 2635 return (0); 2636 ifp = d->bd_bif->bif_ifp; 2637 2638 LIST_FOREACH(bp, &bpf_iflist, bif_next) { 2639 if (bp->bif_ifp == ifp && bp->bif_dlt == dlt) 2640 break; 2641 } 2642 2643 if (bp != NULL) { 2644 opromisc = d->bd_promisc; 2645 bpf_attachd(d, bp); 2646 BPFD_LOCK(d); 2647 reset_d(d); 2648 BPFD_UNLOCK(d); 2649 if (opromisc) { 2650 error = ifpromisc(bp->bif_ifp, 1); 2651 if (error) 2652 if_printf(bp->bif_ifp, 2653 "bpf_setdlt: ifpromisc failed (%d)\n", 2654 error); 2655 else 2656 d->bd_promisc = 1; 2657 } 2658 } 2659 return (bp == NULL ? EINVAL : 0); 2660} 2661 2662static void 2663bpf_drvinit(void *unused) 2664{ 2665 struct cdev *dev; 2666 2667 mtx_init(&bpf_mtx, "bpf global lock", NULL, MTX_DEF); 2668 LIST_INIT(&bpf_iflist); 2669 LIST_INIT(&bpf_freelist); 2670 2671 dev = make_dev(&bpf_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, "bpf"); 2672 /* For compatibility */ 2673 make_dev_alias(dev, "bpf0"); 2674 2675 /* Register interface departure handler */ 2676 bpf_ifdetach_cookie = EVENTHANDLER_REGISTER( 2677 ifnet_departure_event, bpf_ifdetach, NULL, 2678 EVENTHANDLER_PRI_ANY); 2679} 2680 2681/* 2682 * Zero out the various packet counters associated with all of the bpf 2683 * descriptors. At some point, we will probably want to get a bit more 2684 * granular and allow the user to specify descriptors to be zeroed. 2685 */ 2686static void 2687bpf_zero_counters(void) 2688{ 2689 struct bpf_if *bp; 2690 struct bpf_d *bd; 2691 2692 BPF_LOCK(); 2693 LIST_FOREACH(bp, &bpf_iflist, bif_next) { 2694 BPFIF_RLOCK(bp); 2695 LIST_FOREACH(bd, &bp->bif_dlist, bd_next) { 2696 BPFD_LOCK(bd); 2697 bd->bd_rcount = 0; 2698 bd->bd_dcount = 0; 2699 bd->bd_fcount = 0; 2700 bd->bd_wcount = 0; 2701 bd->bd_wfcount = 0; 2702 bd->bd_zcopy = 0; 2703 BPFD_UNLOCK(bd); 2704 } 2705 BPFIF_RUNLOCK(bp); 2706 } 2707 BPF_UNLOCK(); 2708} 2709 2710/* 2711 * Fill filter statistics 2712 */ 2713static void 2714bpfstats_fill_xbpf(struct xbpf_d *d, struct bpf_d *bd) 2715{ 2716 2717 bzero(d, sizeof(*d)); 2718 BPFD_LOCK_ASSERT(bd); 2719 d->bd_structsize = sizeof(*d); 2720 /* XXX: reading should be protected by global lock */ 2721 d->bd_immediate = bd->bd_immediate; 2722 d->bd_promisc = bd->bd_promisc; 2723 d->bd_hdrcmplt = bd->bd_hdrcmplt; 2724 d->bd_direction = bd->bd_direction; 2725 d->bd_feedback = bd->bd_feedback; 2726 d->bd_async = bd->bd_async; 2727 d->bd_rcount = bd->bd_rcount; 2728 d->bd_dcount = bd->bd_dcount; 2729 d->bd_fcount = bd->bd_fcount; 2730 d->bd_sig = bd->bd_sig; 2731 d->bd_slen = bd->bd_slen; 2732 d->bd_hlen = bd->bd_hlen; 2733 d->bd_bufsize = bd->bd_bufsize; 2734 d->bd_pid = bd->bd_pid; 2735 strlcpy(d->bd_ifname, 2736 bd->bd_bif->bif_ifp->if_xname, IFNAMSIZ); 2737 d->bd_locked = bd->bd_locked; 2738 d->bd_wcount = bd->bd_wcount; 2739 d->bd_wdcount = bd->bd_wdcount; 2740 d->bd_wfcount = bd->bd_wfcount; 2741 d->bd_zcopy = bd->bd_zcopy; 2742 d->bd_bufmode = bd->bd_bufmode; 2743} 2744 2745/* 2746 * Handle `netstat -B' stats request 2747 */ 2748static int 2749bpf_stats_sysctl(SYSCTL_HANDLER_ARGS) 2750{ 2751 struct xbpf_d *xbdbuf, *xbd, zerostats; 2752 int index, error; 2753 struct bpf_if *bp; 2754 struct bpf_d *bd; 2755 2756 /* 2757 * XXX This is not technically correct. It is possible for non 2758 * privileged users to open bpf devices. It would make sense 2759 * if the users who opened the devices were able to retrieve 2760 * the statistics for them, too. 2761 */ 2762 error = priv_check(req->td, PRIV_NET_BPF); 2763 if (error) 2764 return (error); 2765 /* 2766 * Check to see if the user is requesting that the counters be 2767 * zeroed out. Explicitly check that the supplied data is zeroed, 2768 * as we aren't allowing the user to set the counters currently. 2769 */ 2770 if (req->newptr != NULL) { 2771 if (req->newlen != sizeof(zerostats)) 2772 return (EINVAL); 2773 bzero(&zerostats, sizeof(zerostats)); 2774 xbd = req->newptr; 2775 if (bcmp(xbd, &zerostats, sizeof(*xbd)) != 0) 2776 return (EINVAL); 2777 bpf_zero_counters(); 2778 return (0); 2779 } 2780 if (req->oldptr == NULL) 2781 return (SYSCTL_OUT(req, 0, bpf_bpfd_cnt * sizeof(*xbd))); 2782 if (bpf_bpfd_cnt == 0) 2783 return (SYSCTL_OUT(req, 0, 0)); 2784 xbdbuf = malloc(req->oldlen, M_BPF, M_WAITOK); 2785 BPF_LOCK(); 2786 if (req->oldlen < (bpf_bpfd_cnt * sizeof(*xbd))) { 2787 BPF_UNLOCK(); 2788 free(xbdbuf, M_BPF); 2789 return (ENOMEM); 2790 } 2791 index = 0; 2792 LIST_FOREACH(bp, &bpf_iflist, bif_next) { 2793 BPFIF_RLOCK(bp); 2794 /* Send writers-only first */ 2795 LIST_FOREACH(bd, &bp->bif_wlist, bd_next) { 2796 xbd = &xbdbuf[index++]; 2797 BPFD_LOCK(bd); 2798 bpfstats_fill_xbpf(xbd, bd); 2799 BPFD_UNLOCK(bd); 2800 } 2801 LIST_FOREACH(bd, &bp->bif_dlist, bd_next) { 2802 xbd = &xbdbuf[index++]; 2803 BPFD_LOCK(bd); 2804 bpfstats_fill_xbpf(xbd, bd); 2805 BPFD_UNLOCK(bd); 2806 } 2807 BPFIF_RUNLOCK(bp); 2808 } 2809 BPF_UNLOCK(); 2810 error = SYSCTL_OUT(req, xbdbuf, index * sizeof(*xbd)); 2811 free(xbdbuf, M_BPF); 2812 return (error); 2813} 2814 2815SYSINIT(bpfdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE,bpf_drvinit,NULL); 2816 2817#else /* !DEV_BPF && !NETGRAPH_BPF */ 2818/* 2819 * NOP stubs to allow bpf-using drivers to load and function. 2820 * 2821 * A 'better' implementation would allow the core bpf functionality 2822 * to be loaded at runtime. 2823 */ 2824static struct bpf_if bp_null; 2825 2826void 2827bpf_tap(struct bpf_if *bp, u_char *pkt, u_int pktlen) 2828{ 2829} 2830 2831void 2832bpf_mtap(struct bpf_if *bp, struct mbuf *m) 2833{ 2834} 2835 2836void 2837bpf_mtap2(struct bpf_if *bp, void *d, u_int l, struct mbuf *m) 2838{ 2839} 2840 2841void 2842bpfattach(struct ifnet *ifp, u_int dlt, u_int hdrlen) 2843{ 2844 2845 bpfattach2(ifp, dlt, hdrlen, &ifp->if_bpf); 2846} 2847 2848void 2849bpfattach2(struct ifnet *ifp, u_int dlt, u_int hdrlen, struct bpf_if **driverp) 2850{ 2851 2852 *driverp = &bp_null; 2853} 2854 2855void 2856bpfdetach(struct ifnet *ifp) 2857{ 2858} 2859 2860u_int 2861bpf_filter(const struct bpf_insn *pc, u_char *p, u_int wirelen, u_int buflen) 2862{ 2863 return -1; /* "no filter" behaviour */ 2864} 2865 2866int 2867bpf_validate(const struct bpf_insn *f, int len) 2868{ 2869 return 0; /* false */ 2870} 2871 2872#endif /* !DEV_BPF && !NETGRAPH_BPF */ 2873