bpf.c revision 198417
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 198417 2009-10-23 17:26:29Z rwatson $"); 39 40#include "opt_bpf.h" 41#include "opt_netgraph.h" 42 43#include <sys/types.h> 44#include <sys/param.h> 45#include <sys/systm.h> 46#include <sys/conf.h> 47#include <sys/fcntl.h> 48#include <sys/jail.h> 49#include <sys/malloc.h> 50#include <sys/mbuf.h> 51#include <sys/time.h> 52#include <sys/priv.h> 53#include <sys/proc.h> 54#include <sys/signalvar.h> 55#include <sys/filio.h> 56#include <sys/sockio.h> 57#include <sys/ttycom.h> 58#include <sys/uio.h> 59 60#include <sys/event.h> 61#include <sys/file.h> 62#include <sys/poll.h> 63#include <sys/proc.h> 64 65#include <sys/socket.h> 66 67#include <net/if.h> 68#include <net/bpf.h> 69#include <net/bpf_buffer.h> 70#ifdef BPF_JITTER 71#include <net/bpf_jitter.h> 72#endif 73#include <net/bpf_zerocopy.h> 74#include <net/bpfdesc.h> 75#include <net/vnet.h> 76 77#include <netinet/in.h> 78#include <netinet/if_ether.h> 79#include <sys/kernel.h> 80#include <sys/sysctl.h> 81 82#include <net80211/ieee80211_freebsd.h> 83 84#include <security/mac/mac_framework.h> 85 86MALLOC_DEFINE(M_BPF, "BPF", "BPF data"); 87 88#if defined(DEV_BPF) || defined(NETGRAPH_BPF) 89 90#define PRINET 26 /* interruptible */ 91 92/* 93 * bpf_iflist is a list of BPF interface structures, each corresponding to a 94 * specific DLT. The same network interface might have several BPF interface 95 * structures registered by different layers in the stack (i.e., 802.11 96 * frames, ethernet frames, etc). 97 */ 98static LIST_HEAD(, bpf_if) bpf_iflist; 99static struct mtx bpf_mtx; /* bpf global lock */ 100static int bpf_bpfd_cnt; 101 102static void bpf_attachd(struct bpf_d *, struct bpf_if *); 103static void bpf_detachd(struct bpf_d *); 104static void bpf_freed(struct bpf_d *); 105static int bpf_movein(struct uio *, int, struct ifnet *, struct mbuf **, 106 struct sockaddr *, int *, struct bpf_insn *); 107static int bpf_setif(struct bpf_d *, struct ifreq *); 108static void bpf_timed_out(void *); 109static __inline void 110 bpf_wakeup(struct bpf_d *); 111static void catchpacket(struct bpf_d *, u_char *, u_int, u_int, 112 void (*)(struct bpf_d *, caddr_t, u_int, void *, u_int), 113 struct timeval *); 114static void reset_d(struct bpf_d *); 115static int bpf_setf(struct bpf_d *, struct bpf_program *, u_long cmd); 116static int bpf_getdltlist(struct bpf_d *, struct bpf_dltlist *); 117static int bpf_setdlt(struct bpf_d *, u_int); 118static void filt_bpfdetach(struct knote *); 119static int filt_bpfread(struct knote *, long); 120static void bpf_drvinit(void *); 121static int bpf_stats_sysctl(SYSCTL_HANDLER_ARGS); 122 123SYSCTL_NODE(_net, OID_AUTO, bpf, CTLFLAG_RW, 0, "bpf sysctl"); 124int bpf_maxinsns = BPF_MAXINSNS; 125SYSCTL_INT(_net_bpf, OID_AUTO, maxinsns, CTLFLAG_RW, 126 &bpf_maxinsns, 0, "Maximum bpf program instructions"); 127static int bpf_zerocopy_enable = 0; 128SYSCTL_INT(_net_bpf, OID_AUTO, zerocopy_enable, CTLFLAG_RW, 129 &bpf_zerocopy_enable, 0, "Enable new zero-copy BPF buffer sessions"); 130SYSCTL_NODE(_net_bpf, OID_AUTO, stats, CTLFLAG_MPSAFE | CTLFLAG_RW, 131 bpf_stats_sysctl, "bpf statistics portal"); 132 133static d_open_t bpfopen; 134static d_read_t bpfread; 135static d_write_t bpfwrite; 136static d_ioctl_t bpfioctl; 137static d_poll_t bpfpoll; 138static d_kqfilter_t bpfkqfilter; 139 140static struct cdevsw bpf_cdevsw = { 141 .d_version = D_VERSION, 142 .d_open = bpfopen, 143 .d_read = bpfread, 144 .d_write = bpfwrite, 145 .d_ioctl = bpfioctl, 146 .d_poll = bpfpoll, 147 .d_name = "bpf", 148 .d_kqfilter = bpfkqfilter, 149}; 150 151static struct filterops bpfread_filtops = { 152 .f_isfd = 1, 153 .f_detach = filt_bpfdetach, 154 .f_event = filt_bpfread, 155}; 156 157/* 158 * Wrapper functions for various buffering methods. If the set of buffer 159 * modes expands, we will probably want to introduce a switch data structure 160 * similar to protosw, et. 161 */ 162static void 163bpf_append_bytes(struct bpf_d *d, caddr_t buf, u_int offset, void *src, 164 u_int len) 165{ 166 167 BPFD_LOCK_ASSERT(d); 168 169 switch (d->bd_bufmode) { 170 case BPF_BUFMODE_BUFFER: 171 return (bpf_buffer_append_bytes(d, buf, offset, src, len)); 172 173 case BPF_BUFMODE_ZBUF: 174 d->bd_zcopy++; 175 return (bpf_zerocopy_append_bytes(d, buf, offset, src, len)); 176 177 default: 178 panic("bpf_buf_append_bytes"); 179 } 180} 181 182static void 183bpf_append_mbuf(struct bpf_d *d, caddr_t buf, u_int offset, void *src, 184 u_int len) 185{ 186 187 BPFD_LOCK_ASSERT(d); 188 189 switch (d->bd_bufmode) { 190 case BPF_BUFMODE_BUFFER: 191 return (bpf_buffer_append_mbuf(d, buf, offset, src, len)); 192 193 case BPF_BUFMODE_ZBUF: 194 d->bd_zcopy++; 195 return (bpf_zerocopy_append_mbuf(d, buf, offset, src, len)); 196 197 default: 198 panic("bpf_buf_append_mbuf"); 199 } 200} 201 202/* 203 * This function gets called when the free buffer is re-assigned. 204 */ 205static void 206bpf_buf_reclaimed(struct bpf_d *d) 207{ 208 209 BPFD_LOCK_ASSERT(d); 210 211 switch (d->bd_bufmode) { 212 case BPF_BUFMODE_BUFFER: 213 return; 214 215 case BPF_BUFMODE_ZBUF: 216 bpf_zerocopy_buf_reclaimed(d); 217 return; 218 219 default: 220 panic("bpf_buf_reclaimed"); 221 } 222} 223 224/* 225 * If the buffer mechanism has a way to decide that a held buffer can be made 226 * free, then it is exposed via the bpf_canfreebuf() interface. (1) is 227 * returned if the buffer can be discarded, (0) is returned if it cannot. 228 */ 229static int 230bpf_canfreebuf(struct bpf_d *d) 231{ 232 233 BPFD_LOCK_ASSERT(d); 234 235 switch (d->bd_bufmode) { 236 case BPF_BUFMODE_ZBUF: 237 return (bpf_zerocopy_canfreebuf(d)); 238 } 239 return (0); 240} 241 242/* 243 * Allow the buffer model to indicate that the current store buffer is 244 * immutable, regardless of the appearance of space. Return (1) if the 245 * buffer is writable, and (0) if not. 246 */ 247static int 248bpf_canwritebuf(struct bpf_d *d) 249{ 250 251 BPFD_LOCK_ASSERT(d); 252 253 switch (d->bd_bufmode) { 254 case BPF_BUFMODE_ZBUF: 255 return (bpf_zerocopy_canwritebuf(d)); 256 } 257 return (1); 258} 259 260/* 261 * Notify buffer model that an attempt to write to the store buffer has 262 * resulted in a dropped packet, in which case the buffer may be considered 263 * full. 264 */ 265static void 266bpf_buffull(struct bpf_d *d) 267{ 268 269 BPFD_LOCK_ASSERT(d); 270 271 switch (d->bd_bufmode) { 272 case BPF_BUFMODE_ZBUF: 273 bpf_zerocopy_buffull(d); 274 break; 275 } 276} 277 278/* 279 * Notify the buffer model that a buffer has moved into the hold position. 280 */ 281void 282bpf_bufheld(struct bpf_d *d) 283{ 284 285 BPFD_LOCK_ASSERT(d); 286 287 switch (d->bd_bufmode) { 288 case BPF_BUFMODE_ZBUF: 289 bpf_zerocopy_bufheld(d); 290 break; 291 } 292} 293 294static void 295bpf_free(struct bpf_d *d) 296{ 297 298 switch (d->bd_bufmode) { 299 case BPF_BUFMODE_BUFFER: 300 return (bpf_buffer_free(d)); 301 302 case BPF_BUFMODE_ZBUF: 303 return (bpf_zerocopy_free(d)); 304 305 default: 306 panic("bpf_buf_free"); 307 } 308} 309 310static int 311bpf_uiomove(struct bpf_d *d, caddr_t buf, u_int len, struct uio *uio) 312{ 313 314 if (d->bd_bufmode != BPF_BUFMODE_BUFFER) 315 return (EOPNOTSUPP); 316 return (bpf_buffer_uiomove(d, buf, len, uio)); 317} 318 319static int 320bpf_ioctl_sblen(struct bpf_d *d, u_int *i) 321{ 322 323 if (d->bd_bufmode != BPF_BUFMODE_BUFFER) 324 return (EOPNOTSUPP); 325 return (bpf_buffer_ioctl_sblen(d, i)); 326} 327 328static int 329bpf_ioctl_getzmax(struct thread *td, struct bpf_d *d, size_t *i) 330{ 331 332 if (d->bd_bufmode != BPF_BUFMODE_ZBUF) 333 return (EOPNOTSUPP); 334 return (bpf_zerocopy_ioctl_getzmax(td, d, i)); 335} 336 337static int 338bpf_ioctl_rotzbuf(struct thread *td, struct bpf_d *d, struct bpf_zbuf *bz) 339{ 340 341 if (d->bd_bufmode != BPF_BUFMODE_ZBUF) 342 return (EOPNOTSUPP); 343 return (bpf_zerocopy_ioctl_rotzbuf(td, d, bz)); 344} 345 346static int 347bpf_ioctl_setzbuf(struct thread *td, struct bpf_d *d, struct bpf_zbuf *bz) 348{ 349 350 if (d->bd_bufmode != BPF_BUFMODE_ZBUF) 351 return (EOPNOTSUPP); 352 return (bpf_zerocopy_ioctl_setzbuf(td, d, bz)); 353} 354 355/* 356 * General BPF functions. 357 */ 358static int 359bpf_movein(struct uio *uio, int linktype, struct ifnet *ifp, struct mbuf **mp, 360 struct sockaddr *sockp, int *hdrlen, struct bpf_insn *wfilter) 361{ 362 const struct ieee80211_bpf_params *p; 363 struct ether_header *eh; 364 struct mbuf *m; 365 int error; 366 int len; 367 int hlen; 368 int slen; 369 370 /* 371 * Build a sockaddr based on the data link layer type. 372 * We do this at this level because the ethernet header 373 * is copied directly into the data field of the sockaddr. 374 * In the case of SLIP, there is no header and the packet 375 * is forwarded as is. 376 * Also, we are careful to leave room at the front of the mbuf 377 * for the link level header. 378 */ 379 switch (linktype) { 380 381 case DLT_SLIP: 382 sockp->sa_family = AF_INET; 383 hlen = 0; 384 break; 385 386 case DLT_EN10MB: 387 sockp->sa_family = AF_UNSPEC; 388 /* XXX Would MAXLINKHDR be better? */ 389 hlen = ETHER_HDR_LEN; 390 break; 391 392 case DLT_FDDI: 393 sockp->sa_family = AF_IMPLINK; 394 hlen = 0; 395 break; 396 397 case DLT_RAW: 398 sockp->sa_family = AF_UNSPEC; 399 hlen = 0; 400 break; 401 402 case DLT_NULL: 403 /* 404 * null interface types require a 4 byte pseudo header which 405 * corresponds to the address family of the packet. 406 */ 407 sockp->sa_family = AF_UNSPEC; 408 hlen = 4; 409 break; 410 411 case DLT_ATM_RFC1483: 412 /* 413 * en atm driver requires 4-byte atm pseudo header. 414 * though it isn't standard, vpi:vci needs to be 415 * specified anyway. 416 */ 417 sockp->sa_family = AF_UNSPEC; 418 hlen = 12; /* XXX 4(ATM_PH) + 3(LLC) + 5(SNAP) */ 419 break; 420 421 case DLT_PPP: 422 sockp->sa_family = AF_UNSPEC; 423 hlen = 4; /* This should match PPP_HDRLEN */ 424 break; 425 426 case DLT_IEEE802_11: /* IEEE 802.11 wireless */ 427 sockp->sa_family = AF_IEEE80211; 428 hlen = 0; 429 break; 430 431 case DLT_IEEE802_11_RADIO: /* IEEE 802.11 wireless w/ phy params */ 432 sockp->sa_family = AF_IEEE80211; 433 sockp->sa_len = 12; /* XXX != 0 */ 434 hlen = sizeof(struct ieee80211_bpf_params); 435 break; 436 437 default: 438 return (EIO); 439 } 440 441 len = uio->uio_resid; 442 443 if (len - hlen > ifp->if_mtu) 444 return (EMSGSIZE); 445 446 if ((unsigned)len > MJUM16BYTES) 447 return (EIO); 448 449 if (len <= MHLEN) 450 MGETHDR(m, M_WAIT, MT_DATA); 451 else if (len <= MCLBYTES) 452 m = m_getcl(M_WAIT, MT_DATA, M_PKTHDR); 453 else 454 m = m_getjcl(M_WAIT, MT_DATA, M_PKTHDR, 455#if (MJUMPAGESIZE > MCLBYTES) 456 len <= MJUMPAGESIZE ? MJUMPAGESIZE : 457#endif 458 (len <= MJUM9BYTES ? MJUM9BYTES : MJUM16BYTES)); 459 m->m_pkthdr.len = m->m_len = len; 460 m->m_pkthdr.rcvif = NULL; 461 *mp = m; 462 463 if (m->m_len < hlen) { 464 error = EPERM; 465 goto bad; 466 } 467 468 error = uiomove(mtod(m, u_char *), len, uio); 469 if (error) 470 goto bad; 471 472 slen = bpf_filter(wfilter, mtod(m, u_char *), len, len); 473 if (slen == 0) { 474 error = EPERM; 475 goto bad; 476 } 477 478 /* Check for multicast destination */ 479 switch (linktype) { 480 case DLT_EN10MB: 481 eh = mtod(m, struct ether_header *); 482 if (ETHER_IS_MULTICAST(eh->ether_dhost)) { 483 if (bcmp(ifp->if_broadcastaddr, eh->ether_dhost, 484 ETHER_ADDR_LEN) == 0) 485 m->m_flags |= M_BCAST; 486 else 487 m->m_flags |= M_MCAST; 488 } 489 break; 490 } 491 492 /* 493 * Make room for link header, and copy it to sockaddr 494 */ 495 if (hlen != 0) { 496 if (sockp->sa_family == AF_IEEE80211) { 497 /* 498 * Collect true length from the parameter header 499 * NB: sockp is known to be zero'd so if we do a 500 * short copy unspecified parameters will be 501 * zero. 502 * NB: packet may not be aligned after stripping 503 * bpf params 504 * XXX check ibp_vers 505 */ 506 p = mtod(m, const struct ieee80211_bpf_params *); 507 hlen = p->ibp_len; 508 if (hlen > sizeof(sockp->sa_data)) { 509 error = EINVAL; 510 goto bad; 511 } 512 } 513 bcopy(m->m_data, sockp->sa_data, hlen); 514 } 515 *hdrlen = hlen; 516 517 return (0); 518bad: 519 m_freem(m); 520 return (error); 521} 522 523/* 524 * Attach file to the bpf interface, i.e. make d listen on bp. 525 */ 526static void 527bpf_attachd(struct bpf_d *d, struct bpf_if *bp) 528{ 529 /* 530 * Point d at bp, and add d to the interface's list of listeners. 531 * Finally, point the driver's bpf cookie at the interface so 532 * it will divert packets to bpf. 533 */ 534 BPFIF_LOCK(bp); 535 d->bd_bif = bp; 536 LIST_INSERT_HEAD(&bp->bif_dlist, d, bd_next); 537 538 bpf_bpfd_cnt++; 539 BPFIF_UNLOCK(bp); 540 541 EVENTHANDLER_INVOKE(bpf_track, bp->bif_ifp, bp->bif_dlt, 1); 542} 543 544/* 545 * Detach a file from its interface. 546 */ 547static void 548bpf_detachd(struct bpf_d *d) 549{ 550 int error; 551 struct bpf_if *bp; 552 struct ifnet *ifp; 553 554 bp = d->bd_bif; 555 BPFIF_LOCK(bp); 556 BPFD_LOCK(d); 557 ifp = d->bd_bif->bif_ifp; 558 559 /* 560 * Remove d from the interface's descriptor list. 561 */ 562 LIST_REMOVE(d, bd_next); 563 564 bpf_bpfd_cnt--; 565 d->bd_bif = NULL; 566 BPFD_UNLOCK(d); 567 BPFIF_UNLOCK(bp); 568 569 EVENTHANDLER_INVOKE(bpf_track, ifp, bp->bif_dlt, 0); 570 571 /* 572 * Check if this descriptor had requested promiscuous mode. 573 * If so, turn it off. 574 */ 575 if (d->bd_promisc) { 576 d->bd_promisc = 0; 577 CURVNET_SET(ifp->if_vnet); 578 error = ifpromisc(ifp, 0); 579 CURVNET_RESTORE(); 580 if (error != 0 && error != ENXIO) { 581 /* 582 * ENXIO can happen if a pccard is unplugged 583 * Something is really wrong if we were able to put 584 * the driver into promiscuous mode, but can't 585 * take it out. 586 */ 587 if_printf(bp->bif_ifp, 588 "bpf_detach: ifpromisc failed (%d)\n", error); 589 } 590 } 591} 592 593/* 594 * Close the descriptor by detaching it from its interface, 595 * deallocating its buffers, and marking it free. 596 */ 597static void 598bpf_dtor(void *data) 599{ 600 struct bpf_d *d = data; 601 602 BPFD_LOCK(d); 603 if (d->bd_state == BPF_WAITING) 604 callout_stop(&d->bd_callout); 605 d->bd_state = BPF_IDLE; 606 BPFD_UNLOCK(d); 607 funsetown(&d->bd_sigio); 608 mtx_lock(&bpf_mtx); 609 if (d->bd_bif) 610 bpf_detachd(d); 611 mtx_unlock(&bpf_mtx); 612 selwakeuppri(&d->bd_sel, PRINET); 613#ifdef MAC 614 mac_bpfdesc_destroy(d); 615#endif /* MAC */ 616 knlist_destroy(&d->bd_sel.si_note); 617 bpf_freed(d); 618 free(d, M_BPF); 619} 620 621/* 622 * Open ethernet device. Returns ENXIO for illegal minor device number, 623 * EBUSY if file is open by another process. 624 */ 625/* ARGSUSED */ 626static int 627bpfopen(struct cdev *dev, int flags, int fmt, struct thread *td) 628{ 629 struct bpf_d *d; 630 int error; 631 632 d = malloc(sizeof(*d), M_BPF, M_WAITOK | M_ZERO); 633 error = devfs_set_cdevpriv(d, bpf_dtor); 634 if (error != 0) { 635 free(d, M_BPF); 636 return (error); 637 } 638 639 /* 640 * For historical reasons, perform a one-time initialization call to 641 * the buffer routines, even though we're not yet committed to a 642 * particular buffer method. 643 */ 644 bpf_buffer_init(d); 645 d->bd_bufmode = BPF_BUFMODE_BUFFER; 646 d->bd_sig = SIGIO; 647 d->bd_direction = BPF_D_INOUT; 648 d->bd_pid = td->td_proc->p_pid; 649#ifdef MAC 650 mac_bpfdesc_init(d); 651 mac_bpfdesc_create(td->td_ucred, d); 652#endif 653 mtx_init(&d->bd_mtx, devtoname(dev), "bpf cdev lock", MTX_DEF); 654 callout_init(&d->bd_callout, CALLOUT_MPSAFE); 655 knlist_init_mtx(&d->bd_sel.si_note, &d->bd_mtx); 656 657 return (0); 658} 659 660/* 661 * bpfread - read next chunk of packets from buffers 662 */ 663static int 664bpfread(struct cdev *dev, struct uio *uio, int ioflag) 665{ 666 struct bpf_d *d; 667 int timed_out; 668 int error; 669 670 error = devfs_get_cdevpriv((void **)&d); 671 if (error != 0) 672 return (error); 673 674 /* 675 * Restrict application to use a buffer the same size as 676 * as kernel buffers. 677 */ 678 if (uio->uio_resid != d->bd_bufsize) 679 return (EINVAL); 680 681 BPFD_LOCK(d); 682 d->bd_pid = curthread->td_proc->p_pid; 683 if (d->bd_bufmode != BPF_BUFMODE_BUFFER) { 684 BPFD_UNLOCK(d); 685 return (EOPNOTSUPP); 686 } 687 if (d->bd_state == BPF_WAITING) 688 callout_stop(&d->bd_callout); 689 timed_out = (d->bd_state == BPF_TIMED_OUT); 690 d->bd_state = BPF_IDLE; 691 /* 692 * If the hold buffer is empty, then do a timed sleep, which 693 * ends when the timeout expires or when enough packets 694 * have arrived to fill the store buffer. 695 */ 696 while (d->bd_hbuf == NULL) { 697 if ((d->bd_immediate || timed_out) && d->bd_slen != 0) { 698 /* 699 * A packet(s) either arrived since the previous 700 * read or arrived while we were asleep. 701 * Rotate the buffers and return what's here. 702 */ 703 ROTATE_BUFFERS(d); 704 break; 705 } 706 707 /* 708 * No data is available, check to see if the bpf device 709 * is still pointed at a real interface. If not, return 710 * ENXIO so that the userland process knows to rebind 711 * it before using it again. 712 */ 713 if (d->bd_bif == NULL) { 714 BPFD_UNLOCK(d); 715 return (ENXIO); 716 } 717 718 if (ioflag & O_NONBLOCK) { 719 BPFD_UNLOCK(d); 720 return (EWOULDBLOCK); 721 } 722 error = msleep(d, &d->bd_mtx, PRINET|PCATCH, 723 "bpf", d->bd_rtout); 724 if (error == EINTR || error == ERESTART) { 725 BPFD_UNLOCK(d); 726 return (error); 727 } 728 if (error == EWOULDBLOCK) { 729 /* 730 * On a timeout, return what's in the buffer, 731 * which may be nothing. If there is something 732 * in the store buffer, we can rotate the buffers. 733 */ 734 if (d->bd_hbuf) 735 /* 736 * We filled up the buffer in between 737 * getting the timeout and arriving 738 * here, so we don't need to rotate. 739 */ 740 break; 741 742 if (d->bd_slen == 0) { 743 BPFD_UNLOCK(d); 744 return (0); 745 } 746 ROTATE_BUFFERS(d); 747 break; 748 } 749 } 750 /* 751 * At this point, we know we have something in the hold slot. 752 */ 753 BPFD_UNLOCK(d); 754 755 /* 756 * Move data from hold buffer into user space. 757 * We know the entire buffer is transferred since 758 * we checked above that the read buffer is bpf_bufsize bytes. 759 * 760 * XXXRW: More synchronization needed here: what if a second thread 761 * issues a read on the same fd at the same time? Don't want this 762 * getting invalidated. 763 */ 764 error = bpf_uiomove(d, d->bd_hbuf, d->bd_hlen, uio); 765 766 BPFD_LOCK(d); 767 d->bd_fbuf = d->bd_hbuf; 768 d->bd_hbuf = NULL; 769 d->bd_hlen = 0; 770 bpf_buf_reclaimed(d); 771 BPFD_UNLOCK(d); 772 773 return (error); 774} 775 776/* 777 * If there are processes sleeping on this descriptor, wake them up. 778 */ 779static __inline void 780bpf_wakeup(struct bpf_d *d) 781{ 782 783 BPFD_LOCK_ASSERT(d); 784 if (d->bd_state == BPF_WAITING) { 785 callout_stop(&d->bd_callout); 786 d->bd_state = BPF_IDLE; 787 } 788 wakeup(d); 789 if (d->bd_async && d->bd_sig && d->bd_sigio) 790 pgsigio(&d->bd_sigio, d->bd_sig, 0); 791 792 selwakeuppri(&d->bd_sel, PRINET); 793 KNOTE_LOCKED(&d->bd_sel.si_note, 0); 794} 795 796static void 797bpf_timed_out(void *arg) 798{ 799 struct bpf_d *d = (struct bpf_d *)arg; 800 801 BPFD_LOCK(d); 802 if (d->bd_state == BPF_WAITING) { 803 d->bd_state = BPF_TIMED_OUT; 804 if (d->bd_slen != 0) 805 bpf_wakeup(d); 806 } 807 BPFD_UNLOCK(d); 808} 809 810static int 811bpf_ready(struct bpf_d *d) 812{ 813 814 BPFD_LOCK_ASSERT(d); 815 816 if (!bpf_canfreebuf(d) && d->bd_hlen != 0) 817 return (1); 818 if ((d->bd_immediate || d->bd_state == BPF_TIMED_OUT) && 819 d->bd_slen != 0) 820 return (1); 821 return (0); 822} 823 824static int 825bpfwrite(struct cdev *dev, struct uio *uio, int ioflag) 826{ 827 struct bpf_d *d; 828 struct ifnet *ifp; 829 struct mbuf *m, *mc; 830 struct sockaddr dst; 831 int error, hlen; 832 833 error = devfs_get_cdevpriv((void **)&d); 834 if (error != 0) 835 return (error); 836 837 d->bd_pid = curthread->td_proc->p_pid; 838 d->bd_wcount++; 839 if (d->bd_bif == NULL) { 840 d->bd_wdcount++; 841 return (ENXIO); 842 } 843 844 ifp = d->bd_bif->bif_ifp; 845 846 if ((ifp->if_flags & IFF_UP) == 0) { 847 d->bd_wdcount++; 848 return (ENETDOWN); 849 } 850 851 if (uio->uio_resid == 0) { 852 d->bd_wdcount++; 853 return (0); 854 } 855 856 bzero(&dst, sizeof(dst)); 857 m = NULL; 858 hlen = 0; 859 error = bpf_movein(uio, (int)d->bd_bif->bif_dlt, ifp, 860 &m, &dst, &hlen, d->bd_wfilter); 861 if (error) { 862 d->bd_wdcount++; 863 return (error); 864 } 865 d->bd_wfcount++; 866 if (d->bd_hdrcmplt) 867 dst.sa_family = pseudo_AF_HDRCMPLT; 868 869 if (d->bd_feedback) { 870 mc = m_dup(m, M_DONTWAIT); 871 if (mc != NULL) 872 mc->m_pkthdr.rcvif = ifp; 873 /* Set M_PROMISC for outgoing packets to be discarded. */ 874 if (d->bd_direction == BPF_D_INOUT) 875 m->m_flags |= M_PROMISC; 876 } else 877 mc = NULL; 878 879 m->m_pkthdr.len -= hlen; 880 m->m_len -= hlen; 881 m->m_data += hlen; /* XXX */ 882 883 CURVNET_SET(ifp->if_vnet); 884#ifdef MAC 885 BPFD_LOCK(d); 886 mac_bpfdesc_create_mbuf(d, m); 887 if (mc != NULL) 888 mac_bpfdesc_create_mbuf(d, mc); 889 BPFD_UNLOCK(d); 890#endif 891 892 error = (*ifp->if_output)(ifp, m, &dst, NULL); 893 if (error) 894 d->bd_wdcount++; 895 896 if (mc != NULL) { 897 if (error == 0) 898 (*ifp->if_input)(ifp, mc); 899 else 900 m_freem(mc); 901 } 902 CURVNET_RESTORE(); 903 904 return (error); 905} 906 907/* 908 * Reset a descriptor by flushing its packet buffer and clearing the receive 909 * and drop counts. This is doable for kernel-only buffers, but with 910 * zero-copy buffers, we can't write to (or rotate) buffers that are 911 * currently owned by userspace. It would be nice if we could encapsulate 912 * this logic in the buffer code rather than here. 913 */ 914static void 915reset_d(struct bpf_d *d) 916{ 917 918 mtx_assert(&d->bd_mtx, MA_OWNED); 919 920 if ((d->bd_hbuf != NULL) && 921 (d->bd_bufmode != BPF_BUFMODE_ZBUF || bpf_canfreebuf(d))) { 922 /* Free the hold buffer. */ 923 d->bd_fbuf = d->bd_hbuf; 924 d->bd_hbuf = NULL; 925 d->bd_hlen = 0; 926 bpf_buf_reclaimed(d); 927 } 928 if (bpf_canwritebuf(d)) 929 d->bd_slen = 0; 930 d->bd_rcount = 0; 931 d->bd_dcount = 0; 932 d->bd_fcount = 0; 933 d->bd_wcount = 0; 934 d->bd_wfcount = 0; 935 d->bd_wdcount = 0; 936 d->bd_zcopy = 0; 937} 938 939/* 940 * FIONREAD Check for read packet available. 941 * SIOCGIFADDR Get interface address - convenient hook to driver. 942 * BIOCGBLEN Get buffer len [for read()]. 943 * BIOCSETF Set read filter. 944 * BIOCSETFNR Set read filter without resetting descriptor. 945 * BIOCSETWF Set write filter. 946 * BIOCFLUSH Flush read packet buffer. 947 * BIOCPROMISC Put interface into promiscuous mode. 948 * BIOCGDLT Get link layer type. 949 * BIOCGETIF Get interface name. 950 * BIOCSETIF Set interface. 951 * BIOCSRTIMEOUT Set read timeout. 952 * BIOCGRTIMEOUT Get read timeout. 953 * BIOCGSTATS Get packet stats. 954 * BIOCIMMEDIATE Set immediate mode. 955 * BIOCVERSION Get filter language version. 956 * BIOCGHDRCMPLT Get "header already complete" flag 957 * BIOCSHDRCMPLT Set "header already complete" flag 958 * BIOCGDIRECTION Get packet direction flag 959 * BIOCSDIRECTION Set packet direction flag 960 * BIOCLOCK Set "locked" flag 961 * BIOCFEEDBACK Set packet feedback mode. 962 * BIOCSETZBUF Set current zero-copy buffer locations. 963 * BIOCGETZMAX Get maximum zero-copy buffer size. 964 * BIOCROTZBUF Force rotation of zero-copy buffer 965 * BIOCSETBUFMODE Set buffer mode. 966 * BIOCGETBUFMODE Get current buffer mode. 967 */ 968/* ARGSUSED */ 969static int 970bpfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, 971 struct thread *td) 972{ 973 struct bpf_d *d; 974 int error; 975 976 error = devfs_get_cdevpriv((void **)&d); 977 if (error != 0) 978 return (error); 979 980 /* 981 * Refresh PID associated with this descriptor. 982 */ 983 BPFD_LOCK(d); 984 d->bd_pid = td->td_proc->p_pid; 985 if (d->bd_state == BPF_WAITING) 986 callout_stop(&d->bd_callout); 987 d->bd_state = BPF_IDLE; 988 BPFD_UNLOCK(d); 989 990 if (d->bd_locked == 1) { 991 switch (cmd) { 992 case BIOCGBLEN: 993 case BIOCFLUSH: 994 case BIOCGDLT: 995 case BIOCGDLTLIST: 996 case BIOCGETIF: 997 case BIOCGRTIMEOUT: 998 case BIOCGSTATS: 999 case BIOCVERSION: 1000 case BIOCGRSIG: 1001 case BIOCGHDRCMPLT: 1002 case BIOCFEEDBACK: 1003 case FIONREAD: 1004 case BIOCLOCK: 1005 case BIOCSRTIMEOUT: 1006 case BIOCIMMEDIATE: 1007 case TIOCGPGRP: 1008 case BIOCROTZBUF: 1009 break; 1010 default: 1011 return (EPERM); 1012 } 1013 } 1014 CURVNET_SET(TD_TO_VNET(td)); 1015 switch (cmd) { 1016 1017 default: 1018 error = EINVAL; 1019 break; 1020 1021 /* 1022 * Check for read packet available. 1023 */ 1024 case FIONREAD: 1025 { 1026 int n; 1027 1028 BPFD_LOCK(d); 1029 n = d->bd_slen; 1030 if (d->bd_hbuf) 1031 n += d->bd_hlen; 1032 BPFD_UNLOCK(d); 1033 1034 *(int *)addr = n; 1035 break; 1036 } 1037 1038 case SIOCGIFADDR: 1039 { 1040 struct ifnet *ifp; 1041 1042 if (d->bd_bif == NULL) 1043 error = EINVAL; 1044 else { 1045 ifp = d->bd_bif->bif_ifp; 1046 error = (*ifp->if_ioctl)(ifp, cmd, addr); 1047 } 1048 break; 1049 } 1050 1051 /* 1052 * Get buffer len [for read()]. 1053 */ 1054 case BIOCGBLEN: 1055 *(u_int *)addr = d->bd_bufsize; 1056 break; 1057 1058 /* 1059 * Set buffer length. 1060 */ 1061 case BIOCSBLEN: 1062 error = bpf_ioctl_sblen(d, (u_int *)addr); 1063 break; 1064 1065 /* 1066 * Set link layer read filter. 1067 */ 1068 case BIOCSETF: 1069 case BIOCSETFNR: 1070 case BIOCSETWF: 1071 error = bpf_setf(d, (struct bpf_program *)addr, cmd); 1072 break; 1073 1074 /* 1075 * Flush read packet buffer. 1076 */ 1077 case BIOCFLUSH: 1078 BPFD_LOCK(d); 1079 reset_d(d); 1080 BPFD_UNLOCK(d); 1081 break; 1082 1083 /* 1084 * Put interface into promiscuous mode. 1085 */ 1086 case BIOCPROMISC: 1087 if (d->bd_bif == NULL) { 1088 /* 1089 * No interface attached yet. 1090 */ 1091 error = EINVAL; 1092 break; 1093 } 1094 if (d->bd_promisc == 0) { 1095 error = ifpromisc(d->bd_bif->bif_ifp, 1); 1096 if (error == 0) 1097 d->bd_promisc = 1; 1098 } 1099 break; 1100 1101 /* 1102 * Get current data link type. 1103 */ 1104 case BIOCGDLT: 1105 if (d->bd_bif == NULL) 1106 error = EINVAL; 1107 else 1108 *(u_int *)addr = d->bd_bif->bif_dlt; 1109 break; 1110 1111 /* 1112 * Get a list of supported data link types. 1113 */ 1114 case BIOCGDLTLIST: 1115 if (d->bd_bif == NULL) 1116 error = EINVAL; 1117 else 1118 error = bpf_getdltlist(d, (struct bpf_dltlist *)addr); 1119 break; 1120 1121 /* 1122 * Set data link type. 1123 */ 1124 case BIOCSDLT: 1125 if (d->bd_bif == NULL) 1126 error = EINVAL; 1127 else 1128 error = bpf_setdlt(d, *(u_int *)addr); 1129 break; 1130 1131 /* 1132 * Get interface name. 1133 */ 1134 case BIOCGETIF: 1135 if (d->bd_bif == NULL) 1136 error = EINVAL; 1137 else { 1138 struct ifnet *const ifp = d->bd_bif->bif_ifp; 1139 struct ifreq *const ifr = (struct ifreq *)addr; 1140 1141 strlcpy(ifr->ifr_name, ifp->if_xname, 1142 sizeof(ifr->ifr_name)); 1143 } 1144 break; 1145 1146 /* 1147 * Set interface. 1148 */ 1149 case BIOCSETIF: 1150 error = bpf_setif(d, (struct ifreq *)addr); 1151 break; 1152 1153 /* 1154 * Set read timeout. 1155 */ 1156 case BIOCSRTIMEOUT: 1157 { 1158 struct timeval *tv = (struct timeval *)addr; 1159 1160 /* 1161 * Subtract 1 tick from tvtohz() since this isn't 1162 * a one-shot timer. 1163 */ 1164 if ((error = itimerfix(tv)) == 0) 1165 d->bd_rtout = tvtohz(tv) - 1; 1166 break; 1167 } 1168 1169 /* 1170 * Get read timeout. 1171 */ 1172 case BIOCGRTIMEOUT: 1173 { 1174 struct timeval *tv = (struct timeval *)addr; 1175 1176 tv->tv_sec = d->bd_rtout / hz; 1177 tv->tv_usec = (d->bd_rtout % hz) * tick; 1178 break; 1179 } 1180 1181 /* 1182 * Get packet stats. 1183 */ 1184 case BIOCGSTATS: 1185 { 1186 struct bpf_stat *bs = (struct bpf_stat *)addr; 1187 1188 /* XXXCSJP overflow */ 1189 bs->bs_recv = d->bd_rcount; 1190 bs->bs_drop = d->bd_dcount; 1191 break; 1192 } 1193 1194 /* 1195 * Set immediate mode. 1196 */ 1197 case BIOCIMMEDIATE: 1198 d->bd_immediate = *(u_int *)addr; 1199 break; 1200 1201 case BIOCVERSION: 1202 { 1203 struct bpf_version *bv = (struct bpf_version *)addr; 1204 1205 bv->bv_major = BPF_MAJOR_VERSION; 1206 bv->bv_minor = BPF_MINOR_VERSION; 1207 break; 1208 } 1209 1210 /* 1211 * Get "header already complete" flag 1212 */ 1213 case BIOCGHDRCMPLT: 1214 *(u_int *)addr = d->bd_hdrcmplt; 1215 break; 1216 1217 /* 1218 * Set "header already complete" flag 1219 */ 1220 case BIOCSHDRCMPLT: 1221 d->bd_hdrcmplt = *(u_int *)addr ? 1 : 0; 1222 break; 1223 1224 /* 1225 * Get packet direction flag 1226 */ 1227 case BIOCGDIRECTION: 1228 *(u_int *)addr = d->bd_direction; 1229 break; 1230 1231 /* 1232 * Set packet direction flag 1233 */ 1234 case BIOCSDIRECTION: 1235 { 1236 u_int direction; 1237 1238 direction = *(u_int *)addr; 1239 switch (direction) { 1240 case BPF_D_IN: 1241 case BPF_D_INOUT: 1242 case BPF_D_OUT: 1243 d->bd_direction = direction; 1244 break; 1245 default: 1246 error = EINVAL; 1247 } 1248 } 1249 break; 1250 1251 case BIOCFEEDBACK: 1252 d->bd_feedback = *(u_int *)addr; 1253 break; 1254 1255 case BIOCLOCK: 1256 d->bd_locked = 1; 1257 break; 1258 1259 case FIONBIO: /* Non-blocking I/O */ 1260 break; 1261 1262 case FIOASYNC: /* Send signal on receive packets */ 1263 d->bd_async = *(int *)addr; 1264 break; 1265 1266 case FIOSETOWN: 1267 error = fsetown(*(int *)addr, &d->bd_sigio); 1268 break; 1269 1270 case FIOGETOWN: 1271 *(int *)addr = fgetown(&d->bd_sigio); 1272 break; 1273 1274 /* This is deprecated, FIOSETOWN should be used instead. */ 1275 case TIOCSPGRP: 1276 error = fsetown(-(*(int *)addr), &d->bd_sigio); 1277 break; 1278 1279 /* This is deprecated, FIOGETOWN should be used instead. */ 1280 case TIOCGPGRP: 1281 *(int *)addr = -fgetown(&d->bd_sigio); 1282 break; 1283 1284 case BIOCSRSIG: /* Set receive signal */ 1285 { 1286 u_int sig; 1287 1288 sig = *(u_int *)addr; 1289 1290 if (sig >= NSIG) 1291 error = EINVAL; 1292 else 1293 d->bd_sig = sig; 1294 break; 1295 } 1296 case BIOCGRSIG: 1297 *(u_int *)addr = d->bd_sig; 1298 break; 1299 1300 case BIOCGETBUFMODE: 1301 *(u_int *)addr = d->bd_bufmode; 1302 break; 1303 1304 case BIOCSETBUFMODE: 1305 /* 1306 * Allow the buffering mode to be changed as long as we 1307 * haven't yet committed to a particular mode. Our 1308 * definition of commitment, for now, is whether or not a 1309 * buffer has been allocated or an interface attached, since 1310 * that's the point where things get tricky. 1311 */ 1312 switch (*(u_int *)addr) { 1313 case BPF_BUFMODE_BUFFER: 1314 break; 1315 1316 case BPF_BUFMODE_ZBUF: 1317 if (bpf_zerocopy_enable) 1318 break; 1319 /* FALLSTHROUGH */ 1320 1321 default: 1322 return (EINVAL); 1323 } 1324 1325 BPFD_LOCK(d); 1326 if (d->bd_sbuf != NULL || d->bd_hbuf != NULL || 1327 d->bd_fbuf != NULL || d->bd_bif != NULL) { 1328 BPFD_UNLOCK(d); 1329 return (EBUSY); 1330 } 1331 d->bd_bufmode = *(u_int *)addr; 1332 BPFD_UNLOCK(d); 1333 break; 1334 1335 case BIOCGETZMAX: 1336 return (bpf_ioctl_getzmax(td, d, (size_t *)addr)); 1337 1338 case BIOCSETZBUF: 1339 return (bpf_ioctl_setzbuf(td, d, (struct bpf_zbuf *)addr)); 1340 1341 case BIOCROTZBUF: 1342 return (bpf_ioctl_rotzbuf(td, d, (struct bpf_zbuf *)addr)); 1343 } 1344 CURVNET_RESTORE(); 1345 return (error); 1346} 1347 1348/* 1349 * Set d's packet filter program to fp. If this file already has a filter, 1350 * free it and replace it. Returns EINVAL for bogus requests. 1351 */ 1352static int 1353bpf_setf(struct bpf_d *d, struct bpf_program *fp, u_long cmd) 1354{ 1355 struct bpf_insn *fcode, *old; 1356 u_int wfilter, flen, size; 1357#ifdef BPF_JITTER 1358 bpf_jit_filter *ofunc; 1359#endif 1360 1361 if (cmd == BIOCSETWF) { 1362 old = d->bd_wfilter; 1363 wfilter = 1; 1364#ifdef BPF_JITTER 1365 ofunc = NULL; 1366#endif 1367 } else { 1368 wfilter = 0; 1369 old = d->bd_rfilter; 1370#ifdef BPF_JITTER 1371 ofunc = d->bd_bfilter; 1372#endif 1373 } 1374 if (fp->bf_insns == NULL) { 1375 if (fp->bf_len != 0) 1376 return (EINVAL); 1377 BPFD_LOCK(d); 1378 if (wfilter) 1379 d->bd_wfilter = NULL; 1380 else { 1381 d->bd_rfilter = NULL; 1382#ifdef BPF_JITTER 1383 d->bd_bfilter = NULL; 1384#endif 1385 if (cmd == BIOCSETF) 1386 reset_d(d); 1387 } 1388 BPFD_UNLOCK(d); 1389 if (old != NULL) 1390 free((caddr_t)old, M_BPF); 1391#ifdef BPF_JITTER 1392 if (ofunc != NULL) 1393 bpf_destroy_jit_filter(ofunc); 1394#endif 1395 return (0); 1396 } 1397 flen = fp->bf_len; 1398 if (flen > bpf_maxinsns) 1399 return (EINVAL); 1400 1401 size = flen * sizeof(*fp->bf_insns); 1402 fcode = (struct bpf_insn *)malloc(size, M_BPF, M_WAITOK); 1403 if (copyin((caddr_t)fp->bf_insns, (caddr_t)fcode, size) == 0 && 1404 bpf_validate(fcode, (int)flen)) { 1405 BPFD_LOCK(d); 1406 if (wfilter) 1407 d->bd_wfilter = fcode; 1408 else { 1409 d->bd_rfilter = fcode; 1410#ifdef BPF_JITTER 1411 d->bd_bfilter = bpf_jitter(fcode, flen); 1412#endif 1413 if (cmd == BIOCSETF) 1414 reset_d(d); 1415 } 1416 BPFD_UNLOCK(d); 1417 if (old != NULL) 1418 free((caddr_t)old, M_BPF); 1419#ifdef BPF_JITTER 1420 if (ofunc != NULL) 1421 bpf_destroy_jit_filter(ofunc); 1422#endif 1423 1424 return (0); 1425 } 1426 free((caddr_t)fcode, M_BPF); 1427 return (EINVAL); 1428} 1429 1430/* 1431 * Detach a file from its current interface (if attached at all) and attach 1432 * to the interface indicated by the name stored in ifr. 1433 * Return an errno or 0. 1434 */ 1435static int 1436bpf_setif(struct bpf_d *d, struct ifreq *ifr) 1437{ 1438 struct bpf_if *bp; 1439 struct ifnet *theywant; 1440 1441 theywant = ifunit(ifr->ifr_name); 1442 if (theywant == NULL || theywant->if_bpf == NULL) 1443 return (ENXIO); 1444 1445 bp = theywant->if_bpf; 1446 1447 /* 1448 * Behavior here depends on the buffering model. If we're using 1449 * kernel memory buffers, then we can allocate them here. If we're 1450 * using zero-copy, then the user process must have registered 1451 * buffers by the time we get here. If not, return an error. 1452 * 1453 * XXXRW: There are locking issues here with multi-threaded use: what 1454 * if two threads try to set the interface at once? 1455 */ 1456 switch (d->bd_bufmode) { 1457 case BPF_BUFMODE_BUFFER: 1458 if (d->bd_sbuf == NULL) 1459 bpf_buffer_alloc(d); 1460 KASSERT(d->bd_sbuf != NULL, ("bpf_setif: bd_sbuf NULL")); 1461 break; 1462 1463 case BPF_BUFMODE_ZBUF: 1464 if (d->bd_sbuf == NULL) 1465 return (EINVAL); 1466 break; 1467 1468 default: 1469 panic("bpf_setif: bufmode %d", d->bd_bufmode); 1470 } 1471 if (bp != d->bd_bif) { 1472 if (d->bd_bif) 1473 /* 1474 * Detach if attached to something else. 1475 */ 1476 bpf_detachd(d); 1477 1478 bpf_attachd(d, bp); 1479 } 1480 BPFD_LOCK(d); 1481 reset_d(d); 1482 BPFD_UNLOCK(d); 1483 return (0); 1484} 1485 1486/* 1487 * Support for select() and poll() system calls 1488 * 1489 * Return true iff the specific operation will not block indefinitely. 1490 * Otherwise, return false but make a note that a selwakeup() must be done. 1491 */ 1492static int 1493bpfpoll(struct cdev *dev, int events, struct thread *td) 1494{ 1495 struct bpf_d *d; 1496 int revents; 1497 1498 if (devfs_get_cdevpriv((void **)&d) != 0 || d->bd_bif == NULL) 1499 return (events & 1500 (POLLHUP|POLLIN|POLLRDNORM|POLLOUT|POLLWRNORM)); 1501 1502 /* 1503 * Refresh PID associated with this descriptor. 1504 */ 1505 revents = events & (POLLOUT | POLLWRNORM); 1506 BPFD_LOCK(d); 1507 d->bd_pid = td->td_proc->p_pid; 1508 if (events & (POLLIN | POLLRDNORM)) { 1509 if (bpf_ready(d)) 1510 revents |= events & (POLLIN | POLLRDNORM); 1511 else { 1512 selrecord(td, &d->bd_sel); 1513 /* Start the read timeout if necessary. */ 1514 if (d->bd_rtout > 0 && d->bd_state == BPF_IDLE) { 1515 callout_reset(&d->bd_callout, d->bd_rtout, 1516 bpf_timed_out, d); 1517 d->bd_state = BPF_WAITING; 1518 } 1519 } 1520 } 1521 BPFD_UNLOCK(d); 1522 return (revents); 1523} 1524 1525/* 1526 * Support for kevent() system call. Register EVFILT_READ filters and 1527 * reject all others. 1528 */ 1529int 1530bpfkqfilter(struct cdev *dev, struct knote *kn) 1531{ 1532 struct bpf_d *d; 1533 1534 if (devfs_get_cdevpriv((void **)&d) != 0 || 1535 kn->kn_filter != EVFILT_READ) 1536 return (1); 1537 1538 /* 1539 * Refresh PID associated with this descriptor. 1540 */ 1541 BPFD_LOCK(d); 1542 d->bd_pid = curthread->td_proc->p_pid; 1543 kn->kn_fop = &bpfread_filtops; 1544 kn->kn_hook = d; 1545 knlist_add(&d->bd_sel.si_note, kn, 1); 1546 BPFD_UNLOCK(d); 1547 1548 return (0); 1549} 1550 1551static void 1552filt_bpfdetach(struct knote *kn) 1553{ 1554 struct bpf_d *d = (struct bpf_d *)kn->kn_hook; 1555 1556 knlist_remove(&d->bd_sel.si_note, kn, 0); 1557} 1558 1559static int 1560filt_bpfread(struct knote *kn, long hint) 1561{ 1562 struct bpf_d *d = (struct bpf_d *)kn->kn_hook; 1563 int ready; 1564 1565 BPFD_LOCK_ASSERT(d); 1566 ready = bpf_ready(d); 1567 if (ready) { 1568 kn->kn_data = d->bd_slen; 1569 if (d->bd_hbuf) 1570 kn->kn_data += d->bd_hlen; 1571 } 1572 else if (d->bd_rtout > 0 && d->bd_state == BPF_IDLE) { 1573 callout_reset(&d->bd_callout, d->bd_rtout, 1574 bpf_timed_out, d); 1575 d->bd_state = BPF_WAITING; 1576 } 1577 1578 return (ready); 1579} 1580 1581/* 1582 * Incoming linkage from device drivers. Process the packet pkt, of length 1583 * pktlen, which is stored in a contiguous buffer. The packet is parsed 1584 * by each process' filter, and if accepted, stashed into the corresponding 1585 * buffer. 1586 */ 1587void 1588bpf_tap(struct bpf_if *bp, u_char *pkt, u_int pktlen) 1589{ 1590 struct bpf_d *d; 1591#ifdef BPF_JITTER 1592 bpf_jit_filter *bf; 1593#endif 1594 u_int slen; 1595 int gottime; 1596 struct timeval tv; 1597 1598 gottime = 0; 1599 BPFIF_LOCK(bp); 1600 LIST_FOREACH(d, &bp->bif_dlist, bd_next) { 1601 BPFD_LOCK(d); 1602 ++d->bd_rcount; 1603 /* 1604 * NB: We dont call BPF_CHECK_DIRECTION() here since there is no 1605 * way for the caller to indiciate to us whether this packet 1606 * is inbound or outbound. In the bpf_mtap() routines, we use 1607 * the interface pointers on the mbuf to figure it out. 1608 */ 1609#ifdef BPF_JITTER 1610 bf = bpf_jitter_enable != 0 ? d->bd_bfilter : NULL; 1611 if (bf != NULL) 1612 slen = (*(bf->func))(pkt, pktlen, pktlen); 1613 else 1614#endif 1615 slen = bpf_filter(d->bd_rfilter, pkt, pktlen, pktlen); 1616 if (slen != 0) { 1617 d->bd_fcount++; 1618 if (!gottime) { 1619 microtime(&tv); 1620 gottime = 1; 1621 } 1622#ifdef MAC 1623 if (mac_bpfdesc_check_receive(d, bp->bif_ifp) == 0) 1624#endif 1625 catchpacket(d, pkt, pktlen, slen, 1626 bpf_append_bytes, &tv); 1627 } 1628 BPFD_UNLOCK(d); 1629 } 1630 BPFIF_UNLOCK(bp); 1631} 1632 1633#define BPF_CHECK_DIRECTION(d, r, i) \ 1634 (((d)->bd_direction == BPF_D_IN && (r) != (i)) || \ 1635 ((d)->bd_direction == BPF_D_OUT && (r) == (i))) 1636 1637/* 1638 * Incoming linkage from device drivers, when packet is in an mbuf chain. 1639 */ 1640void 1641bpf_mtap(struct bpf_if *bp, struct mbuf *m) 1642{ 1643 struct bpf_d *d; 1644#ifdef BPF_JITTER 1645 bpf_jit_filter *bf; 1646#endif 1647 u_int pktlen, slen; 1648 int gottime; 1649 struct timeval tv; 1650 1651 /* Skip outgoing duplicate packets. */ 1652 if ((m->m_flags & M_PROMISC) != 0 && m->m_pkthdr.rcvif == NULL) { 1653 m->m_flags &= ~M_PROMISC; 1654 return; 1655 } 1656 1657 gottime = 0; 1658 1659 pktlen = m_length(m, NULL); 1660 1661 BPFIF_LOCK(bp); 1662 LIST_FOREACH(d, &bp->bif_dlist, bd_next) { 1663 if (BPF_CHECK_DIRECTION(d, m->m_pkthdr.rcvif, bp->bif_ifp)) 1664 continue; 1665 BPFD_LOCK(d); 1666 ++d->bd_rcount; 1667#ifdef BPF_JITTER 1668 bf = bpf_jitter_enable != 0 ? d->bd_bfilter : NULL; 1669 /* XXX We cannot handle multiple mbufs. */ 1670 if (bf != NULL && m->m_next == NULL) 1671 slen = (*(bf->func))(mtod(m, u_char *), pktlen, pktlen); 1672 else 1673#endif 1674 slen = bpf_filter(d->bd_rfilter, (u_char *)m, pktlen, 0); 1675 if (slen != 0) { 1676 d->bd_fcount++; 1677 if (!gottime) { 1678 microtime(&tv); 1679 gottime = 1; 1680 } 1681#ifdef MAC 1682 if (mac_bpfdesc_check_receive(d, bp->bif_ifp) == 0) 1683#endif 1684 catchpacket(d, (u_char *)m, pktlen, slen, 1685 bpf_append_mbuf, &tv); 1686 } 1687 BPFD_UNLOCK(d); 1688 } 1689 BPFIF_UNLOCK(bp); 1690} 1691 1692/* 1693 * Incoming linkage from device drivers, when packet is in 1694 * an mbuf chain and to be prepended by a contiguous header. 1695 */ 1696void 1697bpf_mtap2(struct bpf_if *bp, void *data, u_int dlen, struct mbuf *m) 1698{ 1699 struct mbuf mb; 1700 struct bpf_d *d; 1701 u_int pktlen, slen; 1702 int gottime; 1703 struct timeval tv; 1704 1705 /* Skip outgoing duplicate packets. */ 1706 if ((m->m_flags & M_PROMISC) != 0 && m->m_pkthdr.rcvif == NULL) { 1707 m->m_flags &= ~M_PROMISC; 1708 return; 1709 } 1710 1711 gottime = 0; 1712 1713 pktlen = m_length(m, NULL); 1714 /* 1715 * Craft on-stack mbuf suitable for passing to bpf_filter. 1716 * Note that we cut corners here; we only setup what's 1717 * absolutely needed--this mbuf should never go anywhere else. 1718 */ 1719 mb.m_next = m; 1720 mb.m_data = data; 1721 mb.m_len = dlen; 1722 pktlen += dlen; 1723 1724 BPFIF_LOCK(bp); 1725 LIST_FOREACH(d, &bp->bif_dlist, bd_next) { 1726 if (BPF_CHECK_DIRECTION(d, m->m_pkthdr.rcvif, bp->bif_ifp)) 1727 continue; 1728 BPFD_LOCK(d); 1729 ++d->bd_rcount; 1730 slen = bpf_filter(d->bd_rfilter, (u_char *)&mb, pktlen, 0); 1731 if (slen != 0) { 1732 d->bd_fcount++; 1733 if (!gottime) { 1734 microtime(&tv); 1735 gottime = 1; 1736 } 1737#ifdef MAC 1738 if (mac_bpfdesc_check_receive(d, bp->bif_ifp) == 0) 1739#endif 1740 catchpacket(d, (u_char *)&mb, pktlen, slen, 1741 bpf_append_mbuf, &tv); 1742 } 1743 BPFD_UNLOCK(d); 1744 } 1745 BPFIF_UNLOCK(bp); 1746} 1747 1748#undef BPF_CHECK_DIRECTION 1749 1750/* 1751 * Move the packet data from interface memory (pkt) into the 1752 * store buffer. "cpfn" is the routine called to do the actual data 1753 * transfer. bcopy is passed in to copy contiguous chunks, while 1754 * bpf_append_mbuf is passed in to copy mbuf chains. In the latter case, 1755 * pkt is really an mbuf. 1756 */ 1757static void 1758catchpacket(struct bpf_d *d, u_char *pkt, u_int pktlen, u_int snaplen, 1759 void (*cpfn)(struct bpf_d *, caddr_t, u_int, void *, u_int), 1760 struct timeval *tv) 1761{ 1762 struct bpf_hdr hdr; 1763 int totlen, curlen; 1764 int hdrlen = d->bd_bif->bif_hdrlen; 1765 int do_wakeup = 0; 1766 1767 BPFD_LOCK_ASSERT(d); 1768 1769 /* 1770 * Detect whether user space has released a buffer back to us, and if 1771 * so, move it from being a hold buffer to a free buffer. This may 1772 * not be the best place to do it (for example, we might only want to 1773 * run this check if we need the space), but for now it's a reliable 1774 * spot to do it. 1775 */ 1776 if (d->bd_fbuf == NULL && bpf_canfreebuf(d)) { 1777 d->bd_fbuf = d->bd_hbuf; 1778 d->bd_hbuf = NULL; 1779 d->bd_hlen = 0; 1780 bpf_buf_reclaimed(d); 1781 } 1782 1783 /* 1784 * Figure out how many bytes to move. If the packet is 1785 * greater or equal to the snapshot length, transfer that 1786 * much. Otherwise, transfer the whole packet (unless 1787 * we hit the buffer size limit). 1788 */ 1789 totlen = hdrlen + min(snaplen, pktlen); 1790 if (totlen > d->bd_bufsize) 1791 totlen = d->bd_bufsize; 1792 1793 /* 1794 * Round up the end of the previous packet to the next longword. 1795 * 1796 * Drop the packet if there's no room and no hope of room 1797 * If the packet would overflow the storage buffer or the storage 1798 * buffer is considered immutable by the buffer model, try to rotate 1799 * the buffer and wakeup pending processes. 1800 */ 1801 curlen = BPF_WORDALIGN(d->bd_slen); 1802 if (curlen + totlen > d->bd_bufsize || !bpf_canwritebuf(d)) { 1803 if (d->bd_fbuf == NULL) { 1804 /* 1805 * There's no room in the store buffer, and no 1806 * prospect of room, so drop the packet. Notify the 1807 * buffer model. 1808 */ 1809 bpf_buffull(d); 1810 ++d->bd_dcount; 1811 return; 1812 } 1813 ROTATE_BUFFERS(d); 1814 do_wakeup = 1; 1815 curlen = 0; 1816 } else if (d->bd_immediate || d->bd_state == BPF_TIMED_OUT) 1817 /* 1818 * Immediate mode is set, or the read timeout has already 1819 * expired during a select call. A packet arrived, so the 1820 * reader should be woken up. 1821 */ 1822 do_wakeup = 1; 1823 1824 /* 1825 * Append the bpf header. Note we append the actual header size, but 1826 * move forward the length of the header plus padding. 1827 */ 1828 bzero(&hdr, sizeof(hdr)); 1829 hdr.bh_tstamp = *tv; 1830 hdr.bh_datalen = pktlen; 1831 hdr.bh_hdrlen = hdrlen; 1832 hdr.bh_caplen = totlen - hdrlen; 1833 bpf_append_bytes(d, d->bd_sbuf, curlen, &hdr, sizeof(hdr)); 1834 1835 /* 1836 * Copy the packet data into the store buffer and update its length. 1837 */ 1838 (*cpfn)(d, d->bd_sbuf, curlen + hdrlen, pkt, hdr.bh_caplen); 1839 d->bd_slen = curlen + totlen; 1840 1841 if (do_wakeup) 1842 bpf_wakeup(d); 1843} 1844 1845/* 1846 * Free buffers currently in use by a descriptor. 1847 * Called on close. 1848 */ 1849static void 1850bpf_freed(struct bpf_d *d) 1851{ 1852 1853 /* 1854 * We don't need to lock out interrupts since this descriptor has 1855 * been detached from its interface and it yet hasn't been marked 1856 * free. 1857 */ 1858 bpf_free(d); 1859 if (d->bd_rfilter) { 1860 free((caddr_t)d->bd_rfilter, M_BPF); 1861#ifdef BPF_JITTER 1862 bpf_destroy_jit_filter(d->bd_bfilter); 1863#endif 1864 } 1865 if (d->bd_wfilter) 1866 free((caddr_t)d->bd_wfilter, M_BPF); 1867 mtx_destroy(&d->bd_mtx); 1868} 1869 1870/* 1871 * Attach an interface to bpf. dlt is the link layer type; hdrlen is the 1872 * fixed size of the link header (variable length headers not yet supported). 1873 */ 1874void 1875bpfattach(struct ifnet *ifp, u_int dlt, u_int hdrlen) 1876{ 1877 1878 bpfattach2(ifp, dlt, hdrlen, &ifp->if_bpf); 1879} 1880 1881/* 1882 * Attach an interface to bpf. ifp is a pointer to the structure 1883 * defining the interface to be attached, dlt is the link layer type, 1884 * and hdrlen is the fixed size of the link header (variable length 1885 * headers are not yet supporrted). 1886 */ 1887void 1888bpfattach2(struct ifnet *ifp, u_int dlt, u_int hdrlen, struct bpf_if **driverp) 1889{ 1890 struct bpf_if *bp; 1891 1892 bp = malloc(sizeof(*bp), M_BPF, M_NOWAIT | M_ZERO); 1893 if (bp == NULL) 1894 panic("bpfattach"); 1895 1896 LIST_INIT(&bp->bif_dlist); 1897 bp->bif_ifp = ifp; 1898 bp->bif_dlt = dlt; 1899 mtx_init(&bp->bif_mtx, "bpf interface lock", NULL, MTX_DEF); 1900 KASSERT(*driverp == NULL, ("bpfattach2: driverp already initialized")); 1901 *driverp = bp; 1902 1903 mtx_lock(&bpf_mtx); 1904 LIST_INSERT_HEAD(&bpf_iflist, bp, bif_next); 1905 mtx_unlock(&bpf_mtx); 1906 1907 /* 1908 * Compute the length of the bpf header. This is not necessarily 1909 * equal to SIZEOF_BPF_HDR because we want to insert spacing such 1910 * that the network layer header begins on a longword boundary (for 1911 * performance reasons and to alleviate alignment restrictions). 1912 */ 1913 bp->bif_hdrlen = BPF_WORDALIGN(hdrlen + SIZEOF_BPF_HDR) - hdrlen; 1914 1915 if (bootverbose) 1916 if_printf(ifp, "bpf attached\n"); 1917} 1918 1919/* 1920 * Detach bpf from an interface. This involves detaching each descriptor 1921 * associated with the interface, and leaving bd_bif NULL. Notify each 1922 * descriptor as it's detached so that any sleepers wake up and get 1923 * ENXIO. 1924 */ 1925void 1926bpfdetach(struct ifnet *ifp) 1927{ 1928 struct bpf_if *bp; 1929 struct bpf_d *d; 1930 1931 /* Locate BPF interface information */ 1932 mtx_lock(&bpf_mtx); 1933 LIST_FOREACH(bp, &bpf_iflist, bif_next) { 1934 if (ifp == bp->bif_ifp) 1935 break; 1936 } 1937 1938 /* Interface wasn't attached */ 1939 if ((bp == NULL) || (bp->bif_ifp == NULL)) { 1940 mtx_unlock(&bpf_mtx); 1941 printf("bpfdetach: %s was not attached\n", ifp->if_xname); 1942 return; 1943 } 1944 1945 LIST_REMOVE(bp, bif_next); 1946 mtx_unlock(&bpf_mtx); 1947 1948 while ((d = LIST_FIRST(&bp->bif_dlist)) != NULL) { 1949 bpf_detachd(d); 1950 BPFD_LOCK(d); 1951 bpf_wakeup(d); 1952 BPFD_UNLOCK(d); 1953 } 1954 1955 mtx_destroy(&bp->bif_mtx); 1956 free(bp, M_BPF); 1957} 1958 1959/* 1960 * Get a list of available data link type of the interface. 1961 */ 1962static int 1963bpf_getdltlist(struct bpf_d *d, struct bpf_dltlist *bfl) 1964{ 1965 int n, error; 1966 struct ifnet *ifp; 1967 struct bpf_if *bp; 1968 1969 ifp = d->bd_bif->bif_ifp; 1970 n = 0; 1971 error = 0; 1972 mtx_lock(&bpf_mtx); 1973 LIST_FOREACH(bp, &bpf_iflist, bif_next) { 1974 if (bp->bif_ifp != ifp) 1975 continue; 1976 if (bfl->bfl_list != NULL) { 1977 if (n >= bfl->bfl_len) { 1978 mtx_unlock(&bpf_mtx); 1979 return (ENOMEM); 1980 } 1981 error = copyout(&bp->bif_dlt, 1982 bfl->bfl_list + n, sizeof(u_int)); 1983 } 1984 n++; 1985 } 1986 mtx_unlock(&bpf_mtx); 1987 bfl->bfl_len = n; 1988 return (error); 1989} 1990 1991/* 1992 * Set the data link type of a BPF instance. 1993 */ 1994static int 1995bpf_setdlt(struct bpf_d *d, u_int dlt) 1996{ 1997 int error, opromisc; 1998 struct ifnet *ifp; 1999 struct bpf_if *bp; 2000 2001 if (d->bd_bif->bif_dlt == dlt) 2002 return (0); 2003 ifp = d->bd_bif->bif_ifp; 2004 mtx_lock(&bpf_mtx); 2005 LIST_FOREACH(bp, &bpf_iflist, bif_next) { 2006 if (bp->bif_ifp == ifp && bp->bif_dlt == dlt) 2007 break; 2008 } 2009 mtx_unlock(&bpf_mtx); 2010 if (bp != NULL) { 2011 opromisc = d->bd_promisc; 2012 bpf_detachd(d); 2013 bpf_attachd(d, bp); 2014 BPFD_LOCK(d); 2015 reset_d(d); 2016 BPFD_UNLOCK(d); 2017 if (opromisc) { 2018 error = ifpromisc(bp->bif_ifp, 1); 2019 if (error) 2020 if_printf(bp->bif_ifp, 2021 "bpf_setdlt: ifpromisc failed (%d)\n", 2022 error); 2023 else 2024 d->bd_promisc = 1; 2025 } 2026 } 2027 return (bp == NULL ? EINVAL : 0); 2028} 2029 2030static void 2031bpf_drvinit(void *unused) 2032{ 2033 struct cdev *dev; 2034 2035 mtx_init(&bpf_mtx, "bpf global lock", NULL, MTX_DEF); 2036 LIST_INIT(&bpf_iflist); 2037 2038 dev = make_dev(&bpf_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, "bpf"); 2039 /* For compatibility */ 2040 make_dev_alias(dev, "bpf0"); 2041} 2042 2043/* 2044 * Zero out the various packet counters associated with all of the bpf 2045 * descriptors. At some point, we will probably want to get a bit more 2046 * granular and allow the user to specify descriptors to be zeroed. 2047 */ 2048static void 2049bpf_zero_counters(void) 2050{ 2051 struct bpf_if *bp; 2052 struct bpf_d *bd; 2053 2054 mtx_lock(&bpf_mtx); 2055 LIST_FOREACH(bp, &bpf_iflist, bif_next) { 2056 BPFIF_LOCK(bp); 2057 LIST_FOREACH(bd, &bp->bif_dlist, bd_next) { 2058 BPFD_LOCK(bd); 2059 bd->bd_rcount = 0; 2060 bd->bd_dcount = 0; 2061 bd->bd_fcount = 0; 2062 bd->bd_wcount = 0; 2063 bd->bd_wfcount = 0; 2064 bd->bd_zcopy = 0; 2065 BPFD_UNLOCK(bd); 2066 } 2067 BPFIF_UNLOCK(bp); 2068 } 2069 mtx_unlock(&bpf_mtx); 2070} 2071 2072static void 2073bpfstats_fill_xbpf(struct xbpf_d *d, struct bpf_d *bd) 2074{ 2075 2076 bzero(d, sizeof(*d)); 2077 BPFD_LOCK_ASSERT(bd); 2078 d->bd_structsize = sizeof(*d); 2079 d->bd_immediate = bd->bd_immediate; 2080 d->bd_promisc = bd->bd_promisc; 2081 d->bd_hdrcmplt = bd->bd_hdrcmplt; 2082 d->bd_direction = bd->bd_direction; 2083 d->bd_feedback = bd->bd_feedback; 2084 d->bd_async = bd->bd_async; 2085 d->bd_rcount = bd->bd_rcount; 2086 d->bd_dcount = bd->bd_dcount; 2087 d->bd_fcount = bd->bd_fcount; 2088 d->bd_sig = bd->bd_sig; 2089 d->bd_slen = bd->bd_slen; 2090 d->bd_hlen = bd->bd_hlen; 2091 d->bd_bufsize = bd->bd_bufsize; 2092 d->bd_pid = bd->bd_pid; 2093 strlcpy(d->bd_ifname, 2094 bd->bd_bif->bif_ifp->if_xname, IFNAMSIZ); 2095 d->bd_locked = bd->bd_locked; 2096 d->bd_wcount = bd->bd_wcount; 2097 d->bd_wdcount = bd->bd_wdcount; 2098 d->bd_wfcount = bd->bd_wfcount; 2099 d->bd_zcopy = bd->bd_zcopy; 2100 d->bd_bufmode = bd->bd_bufmode; 2101} 2102 2103static int 2104bpf_stats_sysctl(SYSCTL_HANDLER_ARGS) 2105{ 2106 struct xbpf_d *xbdbuf, *xbd, zerostats; 2107 int index, error; 2108 struct bpf_if *bp; 2109 struct bpf_d *bd; 2110 2111 /* 2112 * XXX This is not technically correct. It is possible for non 2113 * privileged users to open bpf devices. It would make sense 2114 * if the users who opened the devices were able to retrieve 2115 * the statistics for them, too. 2116 */ 2117 error = priv_check(req->td, PRIV_NET_BPF); 2118 if (error) 2119 return (error); 2120 /* 2121 * Check to see if the user is requesting that the counters be 2122 * zeroed out. Explicitly check that the supplied data is zeroed, 2123 * as we aren't allowing the user to set the counters currently. 2124 */ 2125 if (req->newptr != NULL) { 2126 if (req->newlen != sizeof(zerostats)) 2127 return (EINVAL); 2128 bzero(&zerostats, sizeof(zerostats)); 2129 xbd = req->newptr; 2130 if (bcmp(xbd, &zerostats, sizeof(*xbd)) != 0) 2131 return (EINVAL); 2132 bpf_zero_counters(); 2133 return (0); 2134 } 2135 if (req->oldptr == NULL) 2136 return (SYSCTL_OUT(req, 0, bpf_bpfd_cnt * sizeof(*xbd))); 2137 if (bpf_bpfd_cnt == 0) 2138 return (SYSCTL_OUT(req, 0, 0)); 2139 xbdbuf = malloc(req->oldlen, M_BPF, M_WAITOK); 2140 mtx_lock(&bpf_mtx); 2141 if (req->oldlen < (bpf_bpfd_cnt * sizeof(*xbd))) { 2142 mtx_unlock(&bpf_mtx); 2143 free(xbdbuf, M_BPF); 2144 return (ENOMEM); 2145 } 2146 index = 0; 2147 LIST_FOREACH(bp, &bpf_iflist, bif_next) { 2148 BPFIF_LOCK(bp); 2149 LIST_FOREACH(bd, &bp->bif_dlist, bd_next) { 2150 xbd = &xbdbuf[index++]; 2151 BPFD_LOCK(bd); 2152 bpfstats_fill_xbpf(xbd, bd); 2153 BPFD_UNLOCK(bd); 2154 } 2155 BPFIF_UNLOCK(bp); 2156 } 2157 mtx_unlock(&bpf_mtx); 2158 error = SYSCTL_OUT(req, xbdbuf, index * sizeof(*xbd)); 2159 free(xbdbuf, M_BPF); 2160 return (error); 2161} 2162 2163SYSINIT(bpfdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE,bpf_drvinit,NULL); 2164 2165#else /* !DEV_BPF && !NETGRAPH_BPF */ 2166/* 2167 * NOP stubs to allow bpf-using drivers to load and function. 2168 * 2169 * A 'better' implementation would allow the core bpf functionality 2170 * to be loaded at runtime. 2171 */ 2172static struct bpf_if bp_null; 2173 2174void 2175bpf_tap(struct bpf_if *bp, u_char *pkt, u_int pktlen) 2176{ 2177} 2178 2179void 2180bpf_mtap(struct bpf_if *bp, struct mbuf *m) 2181{ 2182} 2183 2184void 2185bpf_mtap2(struct bpf_if *bp, void *d, u_int l, struct mbuf *m) 2186{ 2187} 2188 2189void 2190bpfattach(struct ifnet *ifp, u_int dlt, u_int hdrlen) 2191{ 2192 2193 bpfattach2(ifp, dlt, hdrlen, &ifp->if_bpf); 2194} 2195 2196void 2197bpfattach2(struct ifnet *ifp, u_int dlt, u_int hdrlen, struct bpf_if **driverp) 2198{ 2199 2200 *driverp = &bp_null; 2201} 2202 2203void 2204bpfdetach(struct ifnet *ifp) 2205{ 2206} 2207 2208u_int 2209bpf_filter(const struct bpf_insn *pc, u_char *p, u_int wirelen, u_int buflen) 2210{ 2211 return -1; /* "no filter" behaviour */ 2212} 2213 2214int 2215bpf_validate(const struct bpf_insn *f, int len) 2216{ 2217 return 0; /* false */ 2218} 2219 2220#endif /* !DEV_BPF && !NETGRAPH_BPF */ 2221