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sys/net/bpf.c
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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 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)bpf.c 8.4 (Berkeley) 1/9/95 39 * 40 * $FreeBSD: releng/5.2/sys/net/bpf.c 122352 2003-11-09 09:17:26Z tanimura $ 41 */ 42 43 #include "opt_bpf.h" 44 #include "opt_mac.h" 45 #include "opt_netgraph.h" 46 47 #include <sys/types.h> 48 #include <sys/param.h> 49 #include <sys/systm.h> 50 #include <sys/conf.h> 51 #include <sys/mac.h> 52 #include <sys/malloc.h> 53 #include <sys/mbuf.h> 54 #include <sys/time.h> 55 #include <sys/proc.h> 56 #include <sys/signalvar.h> 57 #include <sys/filio.h> 58 #include <sys/sockio.h> 59 #include <sys/ttycom.h> 60 #include <sys/filedesc.h> 61 62 #include <sys/event.h> 63 #include <sys/file.h> 64 #include <sys/poll.h> 65 #include <sys/proc.h> 66 67 #include <sys/socket.h> 68 #include <sys/vnode.h> 69 70 #include <net/if.h> 71 #include <net/bpf.h> 72 #include <net/bpfdesc.h> 73 74 #include <netinet/in.h> 75 #include <netinet/if_ether.h> 76 #include <sys/kernel.h> 77 #include <sys/sysctl.h> 78 79 static MALLOC_DEFINE(M_BPF, "BPF", "BPF data"); 80 81 #if defined(DEV_BPF) || defined(NETGRAPH_BPF) 82 83 #define PRINET 26 /* interruptible */ 84 85 /* 86 * The default read buffer size is patchable. 87 */ 88 static int bpf_bufsize = 4096; 89 SYSCTL_INT(_debug, OID_AUTO, bpf_bufsize, CTLFLAG_RW, 90 &bpf_bufsize, 0, ""); 91 static int bpf_maxbufsize = BPF_MAXBUFSIZE; 92 SYSCTL_INT(_debug, OID_AUTO, bpf_maxbufsize, CTLFLAG_RW, 93 &bpf_maxbufsize, 0, ""); 94 95 /* 96 * bpf_iflist is the list of interfaces; each corresponds to an ifnet 97 */ 98 static struct bpf_if *bpf_iflist; 99 static struct mtx bpf_mtx; /* bpf global lock */ 100 101 static int bpf_allocbufs(struct bpf_d *); 102 static void bpf_attachd(struct bpf_d *d, struct bpf_if *bp); 103 static void bpf_detachd(struct bpf_d *d); 104 static void bpf_freed(struct bpf_d *); 105 static void bpf_mcopy(const void *, void *, size_t); 106 static int bpf_movein(struct uio *, int, 107 struct mbuf **, struct sockaddr *, int *); 108 static int bpf_setif(struct bpf_d *, struct ifreq *); 109 static void bpf_timed_out(void *); 110 static __inline void 111 bpf_wakeup(struct bpf_d *); 112 static void catchpacket(struct bpf_d *, u_char *, u_int, 113 u_int, void (*)(const void *, void *, size_t)); 114 static void reset_d(struct bpf_d *); 115 static int bpf_setf(struct bpf_d *, struct bpf_program *); 116 static int bpf_getdltlist(struct bpf_d *, struct bpf_dltlist *); 117 static int bpf_setdlt(struct bpf_d *, u_int); 118 static void filt_bpfdetach(struct knote *); 119 static int filt_bpfread(struct knote *, long); 120 121 static d_open_t bpfopen; 122 static d_close_t bpfclose; 123 static d_read_t bpfread; 124 static d_write_t bpfwrite; 125 static d_ioctl_t bpfioctl; 126 static d_poll_t bpfpoll; 127 static d_kqfilter_t bpfkqfilter; 128 129 #define CDEV_MAJOR 23 130 static struct cdevsw bpf_cdevsw = { 131 .d_open = bpfopen, 132 .d_close = bpfclose, 133 .d_read = bpfread, 134 .d_write = bpfwrite, 135 .d_ioctl = bpfioctl, 136 .d_poll = bpfpoll, 137 .d_name = "bpf", 138 .d_maj = CDEV_MAJOR, 139 .d_kqfilter = bpfkqfilter, 140 }; 141 142 static struct filterops bpfread_filtops = 143 { 1, NULL, filt_bpfdetach, filt_bpfread }; 144 145 static int 146 bpf_movein(uio, linktype, mp, sockp, datlen) 147 struct uio *uio; 148 int linktype, *datlen; 149 struct mbuf **mp; 150 struct sockaddr *sockp; 151 { 152 struct mbuf *m; 153 int error; 154 int len; 155 int hlen; 156 157 /* 158 * Build a sockaddr based on the data link layer type. 159 * We do this at this level because the ethernet header 160 * is copied directly into the data field of the sockaddr. 161 * In the case of SLIP, there is no header and the packet 162 * is forwarded as is. 163 * Also, we are careful to leave room at the front of the mbuf 164 * for the link level header. 165 */ 166 switch (linktype) { 167 168 case DLT_SLIP: 169 sockp->sa_family = AF_INET; 170 hlen = 0; 171 break; 172 173 case DLT_EN10MB: 174 sockp->sa_family = AF_UNSPEC; 175 /* XXX Would MAXLINKHDR be better? */ 176 hlen = ETHER_HDR_LEN; 177 break; 178 179 case DLT_FDDI: 180 sockp->sa_family = AF_IMPLINK; 181 hlen = 0; 182 break; 183 184 case DLT_RAW: 185 case DLT_NULL: 186 sockp->sa_family = AF_UNSPEC; 187 hlen = 0; 188 break; 189 190 case DLT_ATM_RFC1483: 191 /* 192 * en atm driver requires 4-byte atm pseudo header. 193 * though it isn't standard, vpi:vci needs to be 194 * specified anyway. 195 */ 196 sockp->sa_family = AF_UNSPEC; 197 hlen = 12; /* XXX 4(ATM_PH) + 3(LLC) + 5(SNAP) */ 198 break; 199 200 case DLT_PPP: 201 sockp->sa_family = AF_UNSPEC; 202 hlen = 4; /* This should match PPP_HDRLEN */ 203 break; 204 205 default: 206 return (EIO); 207 } 208 209 len = uio->uio_resid; 210 *datlen = len - hlen; 211 if ((unsigned)len > MCLBYTES) 212 return (EIO); 213 214 if (len > MHLEN) { 215 m = m_getcl(M_TRYWAIT, MT_DATA, M_PKTHDR); 216 } else { 217 MGETHDR(m, M_TRYWAIT, MT_DATA); 218 } 219 if (m == NULL) 220 return (ENOBUFS); 221 m->m_pkthdr.len = m->m_len = len; 222 m->m_pkthdr.rcvif = NULL; 223 *mp = m; 224 225 /* 226 * Make room for link header. 227 */ 228 if (hlen != 0) { 229 m->m_pkthdr.len -= hlen; 230 m->m_len -= hlen; 231 #if BSD >= 199103 232 m->m_data += hlen; /* XXX */ 233 #else 234 m->m_off += hlen; 235 #endif 236 error = uiomove(sockp->sa_data, hlen, uio); 237 if (error) 238 goto bad; 239 } 240 error = uiomove(mtod(m, void *), len - hlen, uio); 241 if (!error) 242 return (0); 243 bad: 244 m_freem(m); 245 return (error); 246 } 247 248 /* 249 * Attach file to the bpf interface, i.e. make d listen on bp. 250 */ 251 static void 252 bpf_attachd(d, bp) 253 struct bpf_d *d; 254 struct bpf_if *bp; 255 { 256 /* 257 * Point d at bp, and add d to the interface's list of listeners. 258 * Finally, point the driver's bpf cookie at the interface so 259 * it will divert packets to bpf. 260 */ 261 BPFIF_LOCK(bp); 262 d->bd_bif = bp; 263 d->bd_next = bp->bif_dlist; 264 bp->bif_dlist = d; 265 266 *bp->bif_driverp = bp; 267 BPFIF_UNLOCK(bp); 268 } 269 270 /* 271 * Detach a file from its interface. 272 */ 273 static void 274 bpf_detachd(d) 275 struct bpf_d *d; 276 { 277 int error; 278 struct bpf_d **p; 279 struct bpf_if *bp; 280 281 /* XXX locking */ 282 bp = d->bd_bif; 283 d->bd_bif = 0; 284 /* 285 * Check if this descriptor had requested promiscuous mode. 286 * If so, turn it off. 287 */ 288 if (d->bd_promisc) { 289 d->bd_promisc = 0; 290 error = ifpromisc(bp->bif_ifp, 0); 291 if (error != 0 && error != ENXIO) { 292 /* 293 * ENXIO can happen if a pccard is unplugged 294 * Something is really wrong if we were able to put 295 * the driver into promiscuous mode, but can't 296 * take it out. 297 */ 298 if_printf(bp->bif_ifp, 299 "bpf_detach: ifpromisc failed (%d)\n", error); 300 } 301 } 302 /* Remove d from the interface's descriptor list. */ 303 BPFIF_LOCK(bp); 304 p = &bp->bif_dlist; 305 while (*p != d) { 306 p = &(*p)->bd_next; 307 if (*p == 0) 308 panic("bpf_detachd: descriptor not in list"); 309 } 310 *p = (*p)->bd_next; 311 if (bp->bif_dlist == 0) 312 /* 313 * Let the driver know that there are no more listeners. 314 */ 315 *bp->bif_driverp = 0; 316 BPFIF_UNLOCK(bp); 317 } 318 319 /* 320 * Open ethernet device. Returns ENXIO for illegal minor device number, 321 * EBUSY if file is open by another process. 322 */ 323 /* ARGSUSED */ 324 static int 325 bpfopen(dev, flags, fmt, td) 326 dev_t dev; 327 int flags; 328 int fmt; 329 struct thread *td; 330 { 331 struct bpf_d *d; 332 333 mtx_lock(&bpf_mtx); 334 d = dev->si_drv1; 335 /* 336 * Each minor can be opened by only one process. If the requested 337 * minor is in use, return EBUSY. 338 */ 339 if (d) { 340 mtx_unlock(&bpf_mtx); 341 return (EBUSY); 342 } 343 dev->si_drv1 = (struct bpf_d *)~0; /* mark device in use */ 344 mtx_unlock(&bpf_mtx); 345 346 if ((dev->si_flags & SI_NAMED) == 0) 347 make_dev(&bpf_cdevsw, minor(dev), UID_ROOT, GID_WHEEL, 0600, 348 "bpf%d", dev2unit(dev)); 349 MALLOC(d, struct bpf_d *, sizeof(*d), M_BPF, M_WAITOK | M_ZERO); 350 dev->si_drv1 = d; 351 d->bd_bufsize = bpf_bufsize; 352 d->bd_sig = SIGIO; 353 d->bd_seesent = 1; 354 #ifdef MAC 355 mac_init_bpfdesc(d); 356 mac_create_bpfdesc(td->td_ucred, d); 357 #endif 358 mtx_init(&d->bd_mtx, devtoname(dev), "bpf cdev lock", MTX_DEF); 359 callout_init(&d->bd_callout, CALLOUT_MPSAFE); 360 361 return (0); 362 } 363 364 /* 365 * Close the descriptor by detaching it from its interface, 366 * deallocating its buffers, and marking it free. 367 */ 368 /* ARGSUSED */ 369 static int 370 bpfclose(dev, flags, fmt, td) 371 dev_t dev; 372 int flags; 373 int fmt; 374 struct thread *td; 375 { 376 struct bpf_d *d = dev->si_drv1; 377 378 BPFD_LOCK(d); 379 if (d->bd_state == BPF_WAITING) 380 callout_stop(&d->bd_callout); 381 d->bd_state = BPF_IDLE; 382 BPFD_UNLOCK(d); 383 funsetown(&d->bd_sigio); 384 mtx_lock(&bpf_mtx); 385 if (d->bd_bif) 386 bpf_detachd(d); 387 mtx_unlock(&bpf_mtx); 388 #ifdef MAC 389 mac_destroy_bpfdesc(d); 390 #endif /* MAC */ 391 bpf_freed(d); 392 dev->si_drv1 = 0; 393 free(d, M_BPF); 394 395 return (0); 396 } 397 398 399 /* 400 * Rotate the packet buffers in descriptor d. Move the store buffer 401 * into the hold slot, and the free buffer into the store slot. 402 * Zero the length of the new store buffer. 403 */ 404 #define ROTATE_BUFFERS(d) \ 405 (d)->bd_hbuf = (d)->bd_sbuf; \ 406 (d)->bd_hlen = (d)->bd_slen; \ 407 (d)->bd_sbuf = (d)->bd_fbuf; \ 408 (d)->bd_slen = 0; \ 409 (d)->bd_fbuf = 0; 410 /* 411 * bpfread - read next chunk of packets from buffers 412 */ 413 static int 414 bpfread(dev, uio, ioflag) 415 dev_t dev; 416 struct uio *uio; 417 int ioflag; 418 { 419 struct bpf_d *d = dev->si_drv1; 420 int timed_out; 421 int error; 422 423 /* 424 * Restrict application to use a buffer the same size as 425 * as kernel buffers. 426 */ 427 if (uio->uio_resid != d->bd_bufsize) 428 return (EINVAL); 429 430 BPFD_LOCK(d); 431 if (d->bd_state == BPF_WAITING) 432 callout_stop(&d->bd_callout); 433 timed_out = (d->bd_state == BPF_TIMED_OUT); 434 d->bd_state = BPF_IDLE; 435 /* 436 * If the hold buffer is empty, then do a timed sleep, which 437 * ends when the timeout expires or when enough packets 438 * have arrived to fill the store buffer. 439 */ 440 while (d->bd_hbuf == 0) { 441 if ((d->bd_immediate || timed_out) && d->bd_slen != 0) { 442 /* 443 * A packet(s) either arrived since the previous 444 * read or arrived while we were asleep. 445 * Rotate the buffers and return what's here. 446 */ 447 ROTATE_BUFFERS(d); 448 break; 449 } 450 451 /* 452 * No data is available, check to see if the bpf device 453 * is still pointed at a real interface. If not, return 454 * ENXIO so that the userland process knows to rebind 455 * it before using it again. 456 */ 457 if (d->bd_bif == NULL) { 458 BPFD_UNLOCK(d); 459 return (ENXIO); 460 } 461 462 if (ioflag & IO_NDELAY) { 463 BPFD_UNLOCK(d); 464 return (EWOULDBLOCK); 465 } 466 error = msleep(d, &d->bd_mtx, PRINET|PCATCH, 467 "bpf", d->bd_rtout); 468 if (error == EINTR || error == ERESTART) { 469 BPFD_UNLOCK(d); 470 return (error); 471 } 472 if (error == EWOULDBLOCK) { 473 /* 474 * On a timeout, return what's in the buffer, 475 * which may be nothing. If there is something 476 * in the store buffer, we can rotate the buffers. 477 */ 478 if (d->bd_hbuf) 479 /* 480 * We filled up the buffer in between 481 * getting the timeout and arriving 482 * here, so we don't need to rotate. 483 */ 484 break; 485 486 if (d->bd_slen == 0) { 487 BPFD_UNLOCK(d); 488 return (0); 489 } 490 ROTATE_BUFFERS(d); 491 break; 492 } 493 } 494 /* 495 * At this point, we know we have something in the hold slot. 496 */ 497 BPFD_UNLOCK(d); 498 499 /* 500 * Move data from hold buffer into user space. 501 * We know the entire buffer is transferred since 502 * we checked above that the read buffer is bpf_bufsize bytes. 503 */ 504 error = uiomove(d->bd_hbuf, d->bd_hlen, uio); 505 506 BPFD_LOCK(d); 507 d->bd_fbuf = d->bd_hbuf; 508 d->bd_hbuf = 0; 509 d->bd_hlen = 0; 510 BPFD_UNLOCK(d); 511 512 return (error); 513 } 514 515 516 /* 517 * If there are processes sleeping on this descriptor, wake them up. 518 */ 519 static __inline void 520 bpf_wakeup(d) 521 struct bpf_d *d; 522 { 523 if (d->bd_state == BPF_WAITING) { 524 callout_stop(&d->bd_callout); 525 d->bd_state = BPF_IDLE; 526 } 527 wakeup(d); 528 if (d->bd_async && d->bd_sig && d->bd_sigio) 529 pgsigio(&d->bd_sigio, d->bd_sig, 0); 530 531 selwakeuppri(&d->bd_sel, PRINET); 532 KNOTE(&d->bd_sel.si_note, 0); 533 } 534 535 static void 536 bpf_timed_out(arg) 537 void *arg; 538 { 539 struct bpf_d *d = (struct bpf_d *)arg; 540 541 BPFD_LOCK(d); 542 if (d->bd_state == BPF_WAITING) { 543 d->bd_state = BPF_TIMED_OUT; 544 if (d->bd_slen != 0) 545 bpf_wakeup(d); 546 } 547 BPFD_UNLOCK(d); 548 } 549 550 static int 551 bpfwrite(dev, uio, ioflag) 552 dev_t dev; 553 struct uio *uio; 554 int ioflag; 555 { 556 struct bpf_d *d = dev->si_drv1; 557 struct ifnet *ifp; 558 struct mbuf *m; 559 int error; 560 static struct sockaddr dst; 561 int datlen; 562 563 if (d->bd_bif == 0) 564 return (ENXIO); 565 566 ifp = d->bd_bif->bif_ifp; 567 568 if (uio->uio_resid == 0) 569 return (0); 570 571 error = bpf_movein(uio, (int)d->bd_bif->bif_dlt, &m, &dst, &datlen); 572 if (error) 573 return (error); 574 575 if (datlen > ifp->if_mtu) 576 return (EMSGSIZE); 577 578 if (d->bd_hdrcmplt) 579 dst.sa_family = pseudo_AF_HDRCMPLT; 580 581 mtx_lock(&Giant); 582 #ifdef MAC 583 mac_create_mbuf_from_bpfdesc(d, m); 584 #endif 585 error = (*ifp->if_output)(ifp, m, &dst, (struct rtentry *)0); 586 mtx_unlock(&Giant); 587 /* 588 * The driver frees the mbuf. 589 */ 590 return (error); 591 } 592 593 /* 594 * Reset a descriptor by flushing its packet buffer and clearing the 595 * receive and drop counts. 596 */ 597 static void 598 reset_d(d) 599 struct bpf_d *d; 600 { 601 602 mtx_assert(&d->bd_mtx, MA_OWNED); 603 if (d->bd_hbuf) { 604 /* Free the hold buffer. */ 605 d->bd_fbuf = d->bd_hbuf; 606 d->bd_hbuf = 0; 607 } 608 d->bd_slen = 0; 609 d->bd_hlen = 0; 610 d->bd_rcount = 0; 611 d->bd_dcount = 0; 612 } 613 614 /* 615 * FIONREAD Check for read packet available. 616 * SIOCGIFADDR Get interface address - convenient hook to driver. 617 * BIOCGBLEN Get buffer len [for read()]. 618 * BIOCSETF Set ethernet read filter. 619 * BIOCFLUSH Flush read packet buffer. 620 * BIOCPROMISC Put interface into promiscuous mode. 621 * BIOCGDLT Get link layer type. 622 * BIOCGETIF Get interface name. 623 * BIOCSETIF Set interface. 624 * BIOCSRTIMEOUT Set read timeout. 625 * BIOCGRTIMEOUT Get read timeout. 626 * BIOCGSTATS Get packet stats. 627 * BIOCIMMEDIATE Set immediate mode. 628 * BIOCVERSION Get filter language version. 629 * BIOCGHDRCMPLT Get "header already complete" flag 630 * BIOCSHDRCMPLT Set "header already complete" flag 631 * BIOCGSEESENT Get "see packets sent" flag 632 * BIOCSSEESENT Set "see packets sent" flag 633 */ 634 /* ARGSUSED */ 635 static int 636 bpfioctl(dev, cmd, addr, flags, td) 637 dev_t dev; 638 u_long cmd; 639 caddr_t addr; 640 int flags; 641 struct thread *td; 642 { 643 struct bpf_d *d = dev->si_drv1; 644 int error = 0; 645 646 BPFD_LOCK(d); 647 if (d->bd_state == BPF_WAITING) 648 callout_stop(&d->bd_callout); 649 d->bd_state = BPF_IDLE; 650 BPFD_UNLOCK(d); 651 652 switch (cmd) { 653 654 default: 655 error = EINVAL; 656 break; 657 658 /* 659 * Check for read packet available. 660 */ 661 case FIONREAD: 662 { 663 int n; 664 665 BPFD_LOCK(d); 666 n = d->bd_slen; 667 if (d->bd_hbuf) 668 n += d->bd_hlen; 669 BPFD_UNLOCK(d); 670 671 *(int *)addr = n; 672 break; 673 } 674 675 case SIOCGIFADDR: 676 { 677 struct ifnet *ifp; 678 679 if (d->bd_bif == 0) 680 error = EINVAL; 681 else { 682 ifp = d->bd_bif->bif_ifp; 683 error = (*ifp->if_ioctl)(ifp, cmd, addr); 684 } 685 break; 686 } 687 688 /* 689 * Get buffer len [for read()]. 690 */ 691 case BIOCGBLEN: 692 *(u_int *)addr = d->bd_bufsize; 693 break; 694 695 /* 696 * Set buffer length. 697 */ 698 case BIOCSBLEN: 699 if (d->bd_bif != 0) 700 error = EINVAL; 701 else { 702 u_int size = *(u_int *)addr; 703 704 if (size > bpf_maxbufsize) 705 *(u_int *)addr = size = bpf_maxbufsize; 706 else if (size < BPF_MINBUFSIZE) 707 *(u_int *)addr = size = BPF_MINBUFSIZE; 708 d->bd_bufsize = size; 709 } 710 break; 711 712 /* 713 * Set link layer read filter. 714 */ 715 case BIOCSETF: 716 error = bpf_setf(d, (struct bpf_program *)addr); 717 break; 718 719 /* 720 * Flush read packet buffer. 721 */ 722 case BIOCFLUSH: 723 BPFD_LOCK(d); 724 reset_d(d); 725 BPFD_UNLOCK(d); 726 break; 727 728 /* 729 * Put interface into promiscuous mode. 730 */ 731 case BIOCPROMISC: 732 if (d->bd_bif == 0) { 733 /* 734 * No interface attached yet. 735 */ 736 error = EINVAL; 737 break; 738 } 739 if (d->bd_promisc == 0) { 740 mtx_lock(&Giant); 741 error = ifpromisc(d->bd_bif->bif_ifp, 1); 742 mtx_unlock(&Giant); 743 if (error == 0) 744 d->bd_promisc = 1; 745 } 746 break; 747 748 /* 749 * Get current data link type. 750 */ 751 case BIOCGDLT: 752 if (d->bd_bif == 0) 753 error = EINVAL; 754 else 755 *(u_int *)addr = d->bd_bif->bif_dlt; 756 break; 757 758 /* 759 * Get a list of supported data link types. 760 */ 761 case BIOCGDLTLIST: 762 if (d->bd_bif == 0) 763 error = EINVAL; 764 else 765 error = bpf_getdltlist(d, (struct bpf_dltlist *)addr); 766 break; 767 768 /* 769 * Set data link type. 770 */ 771 case BIOCSDLT: 772 if (d->bd_bif == 0) 773 error = EINVAL; 774 else 775 error = bpf_setdlt(d, *(u_int *)addr); 776 break; 777 778 /* 779 * Get interface name. 780 */ 781 case BIOCGETIF: 782 if (d->bd_bif == 0) 783 error = EINVAL; 784 else { 785 struct ifnet *const ifp = d->bd_bif->bif_ifp; 786 struct ifreq *const ifr = (struct ifreq *)addr; 787 788 strlcpy(ifr->ifr_name, ifp->if_xname, 789 sizeof(ifr->ifr_name)); 790 } 791 break; 792 793 /* 794 * Set interface. 795 */ 796 case BIOCSETIF: 797 error = bpf_setif(d, (struct ifreq *)addr); 798 break; 799 800 /* 801 * Set read timeout. 802 */ 803 case BIOCSRTIMEOUT: 804 { 805 struct timeval *tv = (struct timeval *)addr; 806 807 /* 808 * Subtract 1 tick from tvtohz() since this isn't 809 * a one-shot timer. 810 */ 811 if ((error = itimerfix(tv)) == 0) 812 d->bd_rtout = tvtohz(tv) - 1; 813 break; 814 } 815 816 /* 817 * Get read timeout. 818 */ 819 case BIOCGRTIMEOUT: 820 { 821 struct timeval *tv = (struct timeval *)addr; 822 823 tv->tv_sec = d->bd_rtout / hz; 824 tv->tv_usec = (d->bd_rtout % hz) * tick; 825 break; 826 } 827 828 /* 829 * Get packet stats. 830 */ 831 case BIOCGSTATS: 832 { 833 struct bpf_stat *bs = (struct bpf_stat *)addr; 834 835 bs->bs_recv = d->bd_rcount; 836 bs->bs_drop = d->bd_dcount; 837 break; 838 } 839 840 /* 841 * Set immediate mode. 842 */ 843 case BIOCIMMEDIATE: 844 d->bd_immediate = *(u_int *)addr; 845 break; 846 847 case BIOCVERSION: 848 { 849 struct bpf_version *bv = (struct bpf_version *)addr; 850 851 bv->bv_major = BPF_MAJOR_VERSION; 852 bv->bv_minor = BPF_MINOR_VERSION; 853 break; 854 } 855 856 /* 857 * Get "header already complete" flag 858 */ 859 case BIOCGHDRCMPLT: 860 *(u_int *)addr = d->bd_hdrcmplt; 861 break; 862 863 /* 864 * Set "header already complete" flag 865 */ 866 case BIOCSHDRCMPLT: 867 d->bd_hdrcmplt = *(u_int *)addr ? 1 : 0; 868 break; 869 870 /* 871 * Get "see sent packets" flag 872 */ 873 case BIOCGSEESENT: 874 *(u_int *)addr = d->bd_seesent; 875 break; 876 877 /* 878 * Set "see sent packets" flag 879 */ 880 case BIOCSSEESENT: 881 d->bd_seesent = *(u_int *)addr; 882 break; 883 884 case FIONBIO: /* Non-blocking I/O */ 885 break; 886 887 case FIOASYNC: /* Send signal on receive packets */ 888 d->bd_async = *(int *)addr; 889 break; 890 891 case FIOSETOWN: 892 error = fsetown(*(int *)addr, &d->bd_sigio); 893 break; 894 895 case FIOGETOWN: 896 *(int *)addr = fgetown(&d->bd_sigio); 897 break; 898 899 /* This is deprecated, FIOSETOWN should be used instead. */ 900 case TIOCSPGRP: 901 error = fsetown(-(*(int *)addr), &d->bd_sigio); 902 break; 903 904 /* This is deprecated, FIOGETOWN should be used instead. */ 905 case TIOCGPGRP: 906 *(int *)addr = -fgetown(&d->bd_sigio); 907 break; 908 909 case BIOCSRSIG: /* Set receive signal */ 910 { 911 u_int sig; 912 913 sig = *(u_int *)addr; 914 915 if (sig >= NSIG) 916 error = EINVAL; 917 else 918 d->bd_sig = sig; 919 break; 920 } 921 case BIOCGRSIG: 922 *(u_int *)addr = d->bd_sig; 923 break; 924 } 925 return (error); 926 } 927 928 /* 929 * Set d's packet filter program to fp. If this file already has a filter, 930 * free it and replace it. Returns EINVAL for bogus requests. 931 */ 932 static int 933 bpf_setf(d, fp) 934 struct bpf_d *d; 935 struct bpf_program *fp; 936 { 937 struct bpf_insn *fcode, *old; 938 u_int flen, size; 939 940 old = d->bd_filter; 941 if (fp->bf_insns == 0) { 942 if (fp->bf_len != 0) 943 return (EINVAL); 944 BPFD_LOCK(d); 945 d->bd_filter = 0; 946 reset_d(d); 947 BPFD_UNLOCK(d); 948 if (old != 0) 949 free((caddr_t)old, M_BPF); 950 return (0); 951 } 952 flen = fp->bf_len; 953 if (flen > BPF_MAXINSNS) 954 return (EINVAL); 955 956 size = flen * sizeof(*fp->bf_insns); 957 fcode = (struct bpf_insn *)malloc(size, M_BPF, M_WAITOK); 958 if (copyin((caddr_t)fp->bf_insns, (caddr_t)fcode, size) == 0 && 959 bpf_validate(fcode, (int)flen)) { 960 BPFD_LOCK(d); 961 d->bd_filter = fcode; 962 reset_d(d); 963 BPFD_UNLOCK(d); 964 if (old != 0) 965 free((caddr_t)old, M_BPF); 966 967 return (0); 968 } 969 free((caddr_t)fcode, M_BPF); 970 return (EINVAL); 971 } 972 973 /* 974 * Detach a file from its current interface (if attached at all) and attach 975 * to the interface indicated by the name stored in ifr. 976 * Return an errno or 0. 977 */ 978 static int 979 bpf_setif(d, ifr) 980 struct bpf_d *d; 981 struct ifreq *ifr; 982 { 983 struct bpf_if *bp; 984 int error; 985 struct ifnet *theywant; 986 987 theywant = ifunit(ifr->ifr_name); 988 if (theywant == 0) 989 return ENXIO; 990 991 /* 992 * Look through attached interfaces for the named one. 993 */ 994 mtx_lock(&bpf_mtx); 995 for (bp = bpf_iflist; bp != 0; bp = bp->bif_next) { 996 struct ifnet *ifp = bp->bif_ifp; 997 998 if (ifp == 0 || ifp != theywant) 999 continue; 1000 /* skip additional entry */ 1001 if (bp->bif_driverp != (struct bpf_if **)&ifp->if_bpf) 1002 continue; 1003 1004 mtx_unlock(&bpf_mtx); 1005 /* 1006 * We found the requested interface. 1007 * If it's not up, return an error. 1008 * Allocate the packet buffers if we need to. 1009 * If we're already attached to requested interface, 1010 * just flush the buffer. 1011 */ 1012 if ((ifp->if_flags & IFF_UP) == 0) 1013 return (ENETDOWN); 1014 1015 if (d->bd_sbuf == 0) { 1016 error = bpf_allocbufs(d); 1017 if (error != 0) 1018 return (error); 1019 } 1020 if (bp != d->bd_bif) { 1021 if (d->bd_bif) 1022 /* 1023 * Detach if attached to something else. 1024 */ 1025 bpf_detachd(d); 1026 1027 bpf_attachd(d, bp); 1028 } 1029 BPFD_LOCK(d); 1030 reset_d(d); 1031 BPFD_UNLOCK(d); 1032 return (0); 1033 } 1034 mtx_unlock(&bpf_mtx); 1035 /* Not found. */ 1036 return (ENXIO); 1037 } 1038 1039 /* 1040 * Support for select() and poll() system calls 1041 * 1042 * Return true iff the specific operation will not block indefinitely. 1043 * Otherwise, return false but make a note that a selwakeup() must be done. 1044 */ 1045 static int 1046 bpfpoll(dev, events, td) 1047 dev_t dev; 1048 int events; 1049 struct thread *td; 1050 { 1051 struct bpf_d *d; 1052 int revents; 1053 1054 d = dev->si_drv1; 1055 if (d->bd_bif == NULL) 1056 return (ENXIO); 1057 1058 revents = events & (POLLOUT | POLLWRNORM); 1059 BPFD_LOCK(d); 1060 if (events & (POLLIN | POLLRDNORM)) { 1061 if (bpf_ready(d)) 1062 revents |= events & (POLLIN | POLLRDNORM); 1063 else { 1064 selrecord(td, &d->bd_sel); 1065 /* Start the read timeout if necessary. */ 1066 if (d->bd_rtout > 0 && d->bd_state == BPF_IDLE) { 1067 callout_reset(&d->bd_callout, d->bd_rtout, 1068 bpf_timed_out, d); 1069 d->bd_state = BPF_WAITING; 1070 } 1071 } 1072 } 1073 BPFD_UNLOCK(d); 1074 return (revents); 1075 } 1076 1077 /* 1078 * Support for kevent() system call. Register EVFILT_READ filters and 1079 * reject all others. 1080 */ 1081 int 1082 bpfkqfilter(dev, kn) 1083 dev_t dev; 1084 struct knote *kn; 1085 { 1086 struct bpf_d *d = (struct bpf_d *)dev->si_drv1; 1087 1088 if (kn->kn_filter != EVFILT_READ) 1089 return (1); 1090 1091 kn->kn_fop = &bpfread_filtops; 1092 kn->kn_hook = d; 1093 BPFD_LOCK(d); 1094 SLIST_INSERT_HEAD(&d->bd_sel.si_note, kn, kn_selnext); 1095 BPFD_UNLOCK(d); 1096 1097 return (0); 1098 } 1099 1100 static void 1101 filt_bpfdetach(kn) 1102 struct knote *kn; 1103 { 1104 struct bpf_d *d = (struct bpf_d *)kn->kn_hook; 1105 1106 BPFD_LOCK(d); 1107 SLIST_REMOVE(&d->bd_sel.si_note, kn, knote, kn_selnext); 1108 BPFD_UNLOCK(d); 1109 } 1110 1111 static int 1112 filt_bpfread(kn, hint) 1113 struct knote *kn; 1114 long hint; 1115 { 1116 struct bpf_d *d = (struct bpf_d *)kn->kn_hook; 1117 int ready; 1118 1119 BPFD_LOCK(d); 1120 ready = bpf_ready(d); 1121 if (ready) { 1122 kn->kn_data = d->bd_slen; 1123 if (d->bd_hbuf) 1124 kn->kn_data += d->bd_hlen; 1125 } 1126 else if (d->bd_rtout > 0 && d->bd_state == BPF_IDLE) { 1127 callout_reset(&d->bd_callout, d->bd_rtout, 1128 bpf_timed_out, d); 1129 d->bd_state = BPF_WAITING; 1130 } 1131 BPFD_UNLOCK(d); 1132 1133 return (ready); 1134 } 1135 1136 /* 1137 * Incoming linkage from device drivers. Process the packet pkt, of length 1138 * pktlen, which is stored in a contiguous buffer. The packet is parsed 1139 * by each process' filter, and if accepted, stashed into the corresponding 1140 * buffer. 1141 */ 1142 void 1143 bpf_tap(bp, pkt, pktlen) 1144 struct bpf_if *bp; 1145 u_char *pkt; 1146 u_int pktlen; 1147 { 1148 struct bpf_d *d; 1149 u_int slen; 1150 1151 BPFIF_LOCK(bp); 1152 for (d = bp->bif_dlist; d != 0; d = d->bd_next) { 1153 BPFD_LOCK(d); 1154 ++d->bd_rcount; 1155 slen = bpf_filter(d->bd_filter, pkt, pktlen, pktlen); 1156 if (slen != 0) { 1157 #ifdef MAC 1158 if (mac_check_bpfdesc_receive(d, bp->bif_ifp) == 0) 1159 #endif 1160 catchpacket(d, pkt, pktlen, slen, bcopy); 1161 } 1162 BPFD_UNLOCK(d); 1163 } 1164 BPFIF_UNLOCK(bp); 1165 } 1166 1167 /* 1168 * Copy data from an mbuf chain into a buffer. This code is derived 1169 * from m_copydata in sys/uipc_mbuf.c. 1170 */ 1171 static void 1172 bpf_mcopy(src_arg, dst_arg, len) 1173 const void *src_arg; 1174 void *dst_arg; 1175 size_t len; 1176 { 1177 const struct mbuf *m; 1178 u_int count; 1179 u_char *dst; 1180 1181 m = src_arg; 1182 dst = dst_arg; 1183 while (len > 0) { 1184 if (m == 0) 1185 panic("bpf_mcopy"); 1186 count = min(m->m_len, len); 1187 bcopy(mtod(m, void *), dst, count); 1188 m = m->m_next; 1189 dst += count; 1190 len -= count; 1191 } 1192 } 1193 1194 /* 1195 * Incoming linkage from device drivers, when packet is in an mbuf chain. 1196 */ 1197 void 1198 bpf_mtap(bp, m) 1199 struct bpf_if *bp; 1200 struct mbuf *m; 1201 { 1202 struct bpf_d *d; 1203 u_int pktlen, slen; 1204 1205 pktlen = m_length(m, NULL); 1206 if (pktlen == m->m_len) { 1207 bpf_tap(bp, mtod(m, u_char *), pktlen); 1208 return; 1209 } 1210 1211 BPFIF_LOCK(bp); 1212 for (d = bp->bif_dlist; d != 0; d = d->bd_next) { 1213 if (!d->bd_seesent && (m->m_pkthdr.rcvif == NULL)) 1214 continue; 1215 BPFD_LOCK(d); 1216 ++d->bd_rcount; 1217 slen = bpf_filter(d->bd_filter, (u_char *)m, pktlen, 0); 1218 if (slen != 0) 1219 #ifdef MAC 1220 if (mac_check_bpfdesc_receive(d, bp->bif_ifp) == 0) 1221 #endif 1222 catchpacket(d, (u_char *)m, pktlen, slen, 1223 bpf_mcopy); 1224 BPFD_UNLOCK(d); 1225 } 1226 BPFIF_UNLOCK(bp); 1227 } 1228 1229 /* 1230 * Move the packet data from interface memory (pkt) into the 1231 * store buffer. Return 1 if it's time to wakeup a listener (buffer full), 1232 * otherwise 0. "copy" is the routine called to do the actual data 1233 * transfer. bcopy is passed in to copy contiguous chunks, while 1234 * bpf_mcopy is passed in to copy mbuf chains. In the latter case, 1235 * pkt is really an mbuf. 1236 */ 1237 static void 1238 catchpacket(d, pkt, pktlen, snaplen, cpfn) 1239 struct bpf_d *d; 1240 u_char *pkt; 1241 u_int pktlen, snaplen; 1242 void (*cpfn)(const void *, void *, size_t); 1243 { 1244 struct bpf_hdr *hp; 1245 int totlen, curlen; 1246 int hdrlen = d->bd_bif->bif_hdrlen; 1247 /* 1248 * Figure out how many bytes to move. If the packet is 1249 * greater or equal to the snapshot length, transfer that 1250 * much. Otherwise, transfer the whole packet (unless 1251 * we hit the buffer size limit). 1252 */ 1253 totlen = hdrlen + min(snaplen, pktlen); 1254 if (totlen > d->bd_bufsize) 1255 totlen = d->bd_bufsize; 1256 1257 /* 1258 * Round up the end of the previous packet to the next longword. 1259 */ 1260 curlen = BPF_WORDALIGN(d->bd_slen); 1261 if (curlen + totlen > d->bd_bufsize) { 1262 /* 1263 * This packet will overflow the storage buffer. 1264 * Rotate the buffers if we can, then wakeup any 1265 * pending reads. 1266 */ 1267 if (d->bd_fbuf == 0) { 1268 /* 1269 * We haven't completed the previous read yet, 1270 * so drop the packet. 1271 */ 1272 ++d->bd_dcount; 1273 return; 1274 } 1275 ROTATE_BUFFERS(d); 1276 bpf_wakeup(d); 1277 curlen = 0; 1278 } 1279 else if (d->bd_immediate || d->bd_state == BPF_TIMED_OUT) 1280 /* 1281 * Immediate mode is set, or the read timeout has 1282 * already expired during a select call. A packet 1283 * arrived, so the reader should be woken up. 1284 */ 1285 bpf_wakeup(d); 1286 1287 /* 1288 * Append the bpf header. 1289 */ 1290 hp = (struct bpf_hdr *)(d->bd_sbuf + curlen); 1291 microtime(&hp->bh_tstamp); 1292 hp->bh_datalen = pktlen; 1293 hp->bh_hdrlen = hdrlen; 1294 /* 1295 * Copy the packet data into the store buffer and update its length. 1296 */ 1297 (*cpfn)(pkt, (u_char *)hp + hdrlen, (hp->bh_caplen = totlen - hdrlen)); 1298 d->bd_slen = curlen + totlen; 1299 } 1300 1301 /* 1302 * Initialize all nonzero fields of a descriptor. 1303 */ 1304 static int 1305 bpf_allocbufs(d) 1306 struct bpf_d *d; 1307 { 1308 d->bd_fbuf = (caddr_t)malloc(d->bd_bufsize, M_BPF, M_WAITOK); 1309 if (d->bd_fbuf == 0) 1310 return (ENOBUFS); 1311 1312 d->bd_sbuf = (caddr_t)malloc(d->bd_bufsize, M_BPF, M_WAITOK); 1313 if (d->bd_sbuf == 0) { 1314 free(d->bd_fbuf, M_BPF); 1315 return (ENOBUFS); 1316 } 1317 d->bd_slen = 0; 1318 d->bd_hlen = 0; 1319 return (0); 1320 } 1321 1322 /* 1323 * Free buffers currently in use by a descriptor. 1324 * Called on close. 1325 */ 1326 static void 1327 bpf_freed(d) 1328 struct bpf_d *d; 1329 { 1330 /* 1331 * We don't need to lock out interrupts since this descriptor has 1332 * been detached from its interface and it yet hasn't been marked 1333 * free. 1334 */ 1335 if (d->bd_sbuf != 0) { 1336 free(d->bd_sbuf, M_BPF); 1337 if (d->bd_hbuf != 0) 1338 free(d->bd_hbuf, M_BPF); 1339 if (d->bd_fbuf != 0) 1340 free(d->bd_fbuf, M_BPF); 1341 } 1342 if (d->bd_filter) 1343 free((caddr_t)d->bd_filter, M_BPF); 1344 mtx_destroy(&d->bd_mtx); 1345 } 1346 1347 /* 1348 * Attach an interface to bpf. dlt is the link layer type; hdrlen is the 1349 * fixed size of the link header (variable length headers not yet supported). 1350 */ 1351 void 1352 bpfattach(ifp, dlt, hdrlen) 1353 struct ifnet *ifp; 1354 u_int dlt, hdrlen; 1355 { 1356 1357 bpfattach2(ifp, dlt, hdrlen, &ifp->if_bpf); 1358 } 1359 1360 /* 1361 * Attach an interface to bpf. ifp is a pointer to the structure 1362 * defining the interface to be attached, dlt is the link layer type, 1363 * and hdrlen is the fixed size of the link header (variable length 1364 * headers are not yet supporrted). 1365 */ 1366 void 1367 bpfattach2(ifp, dlt, hdrlen, driverp) 1368 struct ifnet *ifp; 1369 u_int dlt, hdrlen; 1370 struct bpf_if **driverp; 1371 { 1372 struct bpf_if *bp; 1373 bp = (struct bpf_if *)malloc(sizeof(*bp), M_BPF, M_NOWAIT | M_ZERO); 1374 if (bp == 0) 1375 panic("bpfattach"); 1376 1377 bp->bif_dlist = 0; 1378 bp->bif_driverp = driverp; 1379 bp->bif_ifp = ifp; 1380 bp->bif_dlt = dlt; 1381 mtx_init(&bp->bif_mtx, "bpf interface lock", NULL, MTX_DEF); 1382 1383 mtx_lock(&bpf_mtx); 1384 bp->bif_next = bpf_iflist; 1385 bpf_iflist = bp; 1386 mtx_unlock(&bpf_mtx); 1387 1388 *bp->bif_driverp = 0; 1389 1390 /* 1391 * Compute the length of the bpf header. This is not necessarily 1392 * equal to SIZEOF_BPF_HDR because we want to insert spacing such 1393 * that the network layer header begins on a longword boundary (for 1394 * performance reasons and to alleviate alignment restrictions). 1395 */ 1396 bp->bif_hdrlen = BPF_WORDALIGN(hdrlen + SIZEOF_BPF_HDR) - hdrlen; 1397 1398 if (bootverbose) 1399 if_printf(ifp, "bpf attached\n"); 1400 } 1401 1402 /* 1403 * Detach bpf from an interface. This involves detaching each descriptor 1404 * associated with the interface, and leaving bd_bif NULL. Notify each 1405 * descriptor as it's detached so that any sleepers wake up and get 1406 * ENXIO. 1407 */ 1408 void 1409 bpfdetach(ifp) 1410 struct ifnet *ifp; 1411 { 1412 struct bpf_if *bp, *bp_prev; 1413 struct bpf_d *d; 1414 1415 /* Locate BPF interface information */ 1416 bp_prev = NULL; 1417 1418 mtx_lock(&bpf_mtx); 1419 for (bp = bpf_iflist; bp != NULL; bp = bp->bif_next) { 1420 if (ifp == bp->bif_ifp) 1421 break; 1422 bp_prev = bp; 1423 } 1424 1425 /* Interface wasn't attached */ 1426 if ((bp == NULL) || (bp->bif_ifp == NULL)) { 1427 mtx_unlock(&bpf_mtx); 1428 printf("bpfdetach: %s was not attached\n", ifp->if_xname); 1429 return; 1430 } 1431 1432 if (bp_prev) { 1433 bp_prev->bif_next = bp->bif_next; 1434 } else { 1435 bpf_iflist = bp->bif_next; 1436 } 1437 mtx_unlock(&bpf_mtx); 1438 1439 while ((d = bp->bif_dlist) != NULL) { 1440 bpf_detachd(d); 1441 BPFD_LOCK(d); 1442 bpf_wakeup(d); 1443 BPFD_UNLOCK(d); 1444 } 1445 1446 mtx_destroy(&bp->bif_mtx); 1447 free(bp, M_BPF); 1448 } 1449 1450 /* 1451 * Get a list of available data link type of the interface. 1452 */ 1453 static int 1454 bpf_getdltlist(d, bfl) 1455 struct bpf_d *d; 1456 struct bpf_dltlist *bfl; 1457 { 1458 int n, error; 1459 struct ifnet *ifp; 1460 struct bpf_if *bp; 1461 1462 ifp = d->bd_bif->bif_ifp; 1463 n = 0; 1464 error = 0; 1465 mtx_lock(&bpf_mtx); 1466 for (bp = bpf_iflist; bp != NULL; bp = bp->bif_next) { 1467 if (bp->bif_ifp != ifp) 1468 continue; 1469 if (bfl->bfl_list != NULL) { 1470 if (n >= bfl->bfl_len) { 1471 mtx_unlock(&bpf_mtx); 1472 return (ENOMEM); 1473 } 1474 error = copyout(&bp->bif_dlt, 1475 bfl->bfl_list + n, sizeof(u_int)); 1476 } 1477 n++; 1478 } 1479 mtx_unlock(&bpf_mtx); 1480 bfl->bfl_len = n; 1481 return (error); 1482 } 1483 1484 /* 1485 * Set the data link type of a BPF instance. 1486 */ 1487 static int 1488 bpf_setdlt(d, dlt) 1489 struct bpf_d *d; 1490 u_int dlt; 1491 { 1492 int error, opromisc; 1493 struct ifnet *ifp; 1494 struct bpf_if *bp; 1495 1496 if (d->bd_bif->bif_dlt == dlt) 1497 return (0); 1498 ifp = d->bd_bif->bif_ifp; 1499 mtx_lock(&bpf_mtx); 1500 for (bp = bpf_iflist; bp != NULL; bp = bp->bif_next) { 1501 if (bp->bif_ifp == ifp && bp->bif_dlt == dlt) 1502 break; 1503 } 1504 mtx_unlock(&bpf_mtx); 1505 if (bp != NULL) { 1506 BPFD_LOCK(d); 1507 opromisc = d->bd_promisc; 1508 bpf_detachd(d); 1509 bpf_attachd(d, bp); 1510 reset_d(d); 1511 BPFD_UNLOCK(d); 1512 if (opromisc) { 1513 error = ifpromisc(bp->bif_ifp, 1); 1514 if (error) 1515 if_printf(bp->bif_ifp, 1516 "bpf_setdlt: ifpromisc failed (%d)\n", 1517 error); 1518 else 1519 d->bd_promisc = 1; 1520 } 1521 } 1522 return (bp == NULL ? EINVAL : 0); 1523 } 1524 1525 static void bpf_drvinit(void *unused); 1526 1527 static void bpf_clone(void *arg, char *name, int namelen, dev_t *dev); 1528 1529 static void 1530 bpf_clone(arg, name, namelen, dev) 1531 void *arg; 1532 char *name; 1533 int namelen; 1534 dev_t *dev; 1535 { 1536 int u; 1537 1538 if (*dev != NODEV) 1539 return; 1540 if (dev_stdclone(name, NULL, "bpf", &u) != 1) 1541 return; 1542 *dev = make_dev(&bpf_cdevsw, unit2minor(u), UID_ROOT, GID_WHEEL, 0600, 1543 "bpf%d", u); 1544 (*dev)->si_flags |= SI_CHEAPCLONE; 1545 return; 1546 } 1547 1548 static void 1549 bpf_drvinit(unused) 1550 void *unused; 1551 { 1552 1553 mtx_init(&bpf_mtx, "bpf global lock", NULL, MTX_DEF); 1554 EVENTHANDLER_REGISTER(dev_clone, bpf_clone, 0, 1000); 1555 } 1556 1557 SYSINIT(bpfdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,bpf_drvinit,NULL) 1558 1559 #else /* !DEV_BPF && !NETGRAPH_BPF */ 1560 /* 1561 * NOP stubs to allow bpf-using drivers to load and function. 1562 * 1563 * A 'better' implementation would allow the core bpf functionality 1564 * to be loaded at runtime. 1565 */ 1566 1567 void 1568 bpf_tap(bp, pkt, pktlen) 1569 struct bpf_if *bp; 1570 u_char *pkt; 1571 u_int pktlen; 1572 { 1573 } 1574 1575 void 1576 bpf_mtap(bp, m) 1577 struct bpf_if *bp; 1578 struct mbuf *m; 1579 { 1580 } 1581 1582 void 1583 bpfattach(ifp, dlt, hdrlen) 1584 struct ifnet *ifp; 1585 u_int dlt, hdrlen; 1586 { 1587 } 1588 1589 void 1590 bpfattach2(ifp, dlt, hdrlen, driverp) 1591 struct ifnet *ifp; 1592 u_int dlt, hdrlen; 1593 struct bpf_if **driverp; 1594 { 1595 } 1596 1597 void 1598 bpfdetach(ifp) 1599 struct ifnet *ifp; 1600 { 1601 } 1602 1603 u_int 1604 bpf_filter(pc, p, wirelen, buflen) 1605 const struct bpf_insn *pc; 1606 u_char *p; 1607 u_int wirelen; 1608 u_int buflen; 1609 { 1610 return -1; /* "no filter" behaviour */ 1611 } 1612 1613 int 1614 bpf_validate(f, len) 1615 const struct bpf_insn *f; 1616 int len; 1617 { 1618 return 0; /* false */ 1619 } 1620 1621 #endif /* !DEV_BPF && !NETGRAPH_BPF */
Cache object: 4e6fe1e33bbbe8f5e27636fe2c54a49e
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