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 8.2 (Berkeley) 3/28/94 39 * 40 * $FreeBSD: src/sys/net/bpf.c,v 1.59.2.12 2002/04/14 21:41:48 luigi Exp $ 41 * $DragonFly: src/sys/net/bpf.c,v 1.50 2008/09/23 11:28:49 sephe Exp $ 42 */ 43 44 #include "use_bpf.h" 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/conf.h> 49 #include <sys/device.h> 50 #include <sys/malloc.h> 51 #include <sys/mbuf.h> 52 #include <sys/time.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/filedesc.h> 59 60 #include <sys/poll.h> 61 62 #include <sys/socket.h> 63 #include <sys/vnode.h> 64 65 #include <sys/thread2.h> 66 #include <sys/mplock2.h> 67 68 #include <net/if.h> 69 #include <net/bpf.h> 70 #include <net/bpfdesc.h> 71 #include <net/netmsg2.h> 72 73 #include <netinet/in.h> 74 #include <netinet/if_ether.h> 75 #include <sys/kernel.h> 76 #include <sys/sysctl.h> 77 78 #include <sys/devfs.h> 79 80 struct netmsg_bpf_output { 81 struct netmsg nm_netmsg; 82 struct mbuf *nm_mbuf; 83 struct ifnet *nm_ifp; 84 struct sockaddr *nm_dst; 85 }; 86 87 MALLOC_DEFINE(M_BPF, "BPF", "BPF data"); 88 DEVFS_DECLARE_CLONE_BITMAP(bpf); 89 90 #if NBPF <= 1 91 #define BPF_PREALLOCATED_UNITS 4 92 #else 93 #define BPF_PREALLOCATED_UNITS NBPF 94 #endif 95 96 #if NBPF > 0 97 98 /* 99 * The default read buffer size is patchable. 100 */ 101 static int bpf_bufsize = BPF_DEFAULTBUFSIZE; 102 SYSCTL_INT(_debug, OID_AUTO, bpf_bufsize, CTLFLAG_RW, 103 &bpf_bufsize, 0, ""); 104 int bpf_maxbufsize = BPF_MAXBUFSIZE; 105 SYSCTL_INT(_debug, OID_AUTO, bpf_maxbufsize, CTLFLAG_RW, 106 &bpf_maxbufsize, 0, ""); 107 108 /* 109 * bpf_iflist is the list of interfaces; each corresponds to an ifnet 110 */ 111 static struct bpf_if *bpf_iflist; 112 113 static int bpf_allocbufs(struct bpf_d *); 114 static void bpf_attachd(struct bpf_d *d, struct bpf_if *bp); 115 static void bpf_detachd(struct bpf_d *d); 116 static void bpf_resetd(struct bpf_d *); 117 static void bpf_freed(struct bpf_d *); 118 static void bpf_mcopy(const void *, void *, size_t); 119 static int bpf_movein(struct uio *, int, struct mbuf **, 120 struct sockaddr *, int *, struct bpf_insn *); 121 static int bpf_setif(struct bpf_d *, struct ifreq *); 122 static void bpf_timed_out(void *); 123 static void bpf_wakeup(struct bpf_d *); 124 static void catchpacket(struct bpf_d *, u_char *, u_int, u_int, 125 void (*)(const void *, void *, size_t), 126 const struct timeval *); 127 static int bpf_setf(struct bpf_d *, struct bpf_program *, u_long cmd); 128 static int bpf_getdltlist(struct bpf_d *, struct bpf_dltlist *); 129 static int bpf_setdlt(struct bpf_d *, u_int); 130 static void bpf_drvinit(void *unused); 131 132 static d_open_t bpfopen; 133 static d_clone_t bpfclone; 134 static d_close_t bpfclose; 135 static d_read_t bpfread; 136 static d_write_t bpfwrite; 137 static d_ioctl_t bpfioctl; 138 static d_poll_t bpfpoll; 139 140 #define CDEV_MAJOR 23 141 static struct dev_ops bpf_ops = { 142 { "bpf", CDEV_MAJOR, 0 }, 143 .d_open = bpfopen, 144 .d_close = bpfclose, 145 .d_read = bpfread, 146 .d_write = bpfwrite, 147 .d_ioctl = bpfioctl, 148 .d_poll = bpfpoll, 149 }; 150 151 152 static int 153 bpf_movein(struct uio *uio, int linktype, struct mbuf **mp, 154 struct sockaddr *sockp, int *datlen, struct bpf_insn *wfilter) 155 { 156 struct mbuf *m; 157 int error; 158 int len; 159 int hlen; 160 int slen; 161 162 *datlen = 0; 163 *mp = NULL; 164 165 /* 166 * Build a sockaddr based on the data link layer type. 167 * We do this at this level because the ethernet header 168 * is copied directly into the data field of the sockaddr. 169 * In the case of SLIP, there is no header and the packet 170 * is forwarded as is. 171 * Also, we are careful to leave room at the front of the mbuf 172 * for the link level header. 173 */ 174 switch (linktype) { 175 case DLT_SLIP: 176 sockp->sa_family = AF_INET; 177 hlen = 0; 178 break; 179 180 case DLT_EN10MB: 181 sockp->sa_family = AF_UNSPEC; 182 /* XXX Would MAXLINKHDR be better? */ 183 hlen = sizeof(struct ether_header); 184 break; 185 186 case DLT_RAW: 187 case DLT_NULL: 188 sockp->sa_family = AF_UNSPEC; 189 hlen = 0; 190 break; 191 192 case DLT_ATM_RFC1483: 193 /* 194 * en atm driver requires 4-byte atm pseudo header. 195 * though it isn't standard, vpi:vci needs to be 196 * specified anyway. 197 */ 198 sockp->sa_family = AF_UNSPEC; 199 hlen = 12; /* XXX 4(ATM_PH) + 3(LLC) + 5(SNAP) */ 200 break; 201 202 case DLT_PPP: 203 sockp->sa_family = AF_UNSPEC; 204 hlen = 4; /* This should match PPP_HDRLEN */ 205 break; 206 207 default: 208 return(EIO); 209 } 210 211 len = uio->uio_resid; 212 *datlen = len - hlen; 213 if ((unsigned)len > MCLBYTES) 214 return(EIO); 215 216 m = m_getl(len, MB_WAIT, MT_DATA, M_PKTHDR, NULL); 217 if (m == NULL) 218 return(ENOBUFS); 219 m->m_pkthdr.len = m->m_len = len; 220 m->m_pkthdr.rcvif = NULL; 221 *mp = m; 222 223 if (m->m_len < hlen) { 224 error = EPERM; 225 goto bad; 226 } 227 228 error = uiomove(mtod(m, u_char *), len, uio); 229 if (error) 230 goto bad; 231 232 slen = bpf_filter(wfilter, mtod(m, u_char *), len, len); 233 if (slen == 0) { 234 error = EPERM; 235 goto bad; 236 } 237 238 /* 239 * Make room for link header, and copy it to sockaddr. 240 */ 241 if (hlen != 0) { 242 bcopy(m->m_data, sockp->sa_data, hlen); 243 m->m_pkthdr.len -= hlen; 244 m->m_len -= hlen; 245 m->m_data += hlen; /* XXX */ 246 } 247 return (0); 248 bad: 249 m_freem(m); 250 return(error); 251 } 252 253 /* 254 * Attach file to the bpf interface, i.e. make d listen on bp. 255 * Must be called at splimp. 256 */ 257 static void 258 bpf_attachd(struct bpf_d *d, struct bpf_if *bp) 259 { 260 /* 261 * Point d at bp, and add d to the interface's list of listeners. 262 * Finally, point the driver's bpf cookie at the interface so 263 * it will divert packets to bpf. 264 */ 265 d->bd_bif = bp; 266 SLIST_INSERT_HEAD(&bp->bif_dlist, d, bd_next); 267 *bp->bif_driverp = bp; 268 269 EVENTHANDLER_INVOKE(bpf_track, bp->bif_ifp, bp->bif_dlt, 1); 270 } 271 272 /* 273 * Detach a file from its interface. 274 */ 275 static void 276 bpf_detachd(struct bpf_d *d) 277 { 278 int error; 279 struct bpf_if *bp; 280 struct ifnet *ifp; 281 282 bp = d->bd_bif; 283 ifp = bp->bif_ifp; 284 285 /* Remove d from the interface's descriptor list. */ 286 SLIST_REMOVE(&bp->bif_dlist, d, bpf_d, bd_next); 287 288 if (SLIST_EMPTY(&bp->bif_dlist)) { 289 /* 290 * Let the driver know that there are no more listeners. 291 */ 292 *bp->bif_driverp = NULL; 293 } 294 d->bd_bif = NULL; 295 296 EVENTHANDLER_INVOKE(bpf_track, ifp, bp->bif_dlt, 0); 297 298 /* 299 * Check if this descriptor had requested promiscuous mode. 300 * If so, turn it off. 301 */ 302 if (d->bd_promisc) { 303 d->bd_promisc = 0; 304 error = ifpromisc(ifp, 0); 305 if (error != 0 && error != ENXIO) { 306 /* 307 * ENXIO can happen if a pccard is unplugged, 308 * Something is really wrong if we were able to put 309 * the driver into promiscuous mode, but can't 310 * take it out. 311 */ 312 if_printf(ifp, "bpf_detach: ifpromisc failed(%d)\n", 313 error); 314 } 315 } 316 } 317 318 /* 319 * Open ethernet device. Returns ENXIO for illegal minor device number, 320 * EBUSY if file is open by another process. 321 */ 322 /* ARGSUSED */ 323 static int 324 bpfopen(struct dev_open_args *ap) 325 { 326 cdev_t dev = ap->a_head.a_dev; 327 struct bpf_d *d; 328 329 if (ap->a_cred->cr_prison) 330 return(EPERM); 331 332 d = dev->si_drv1; 333 /* 334 * Each minor can be opened by only one process. If the requested 335 * minor is in use, return EBUSY. 336 */ 337 if (d != NULL) 338 return(EBUSY); 339 340 MALLOC(d, struct bpf_d *, sizeof *d, M_BPF, M_WAITOK | M_ZERO); 341 dev->si_drv1 = d; 342 d->bd_bufsize = bpf_bufsize; 343 d->bd_sig = SIGIO; 344 d->bd_seesent = 1; 345 callout_init(&d->bd_callout); 346 return(0); 347 } 348 349 static int 350 bpfclone(struct dev_clone_args *ap) 351 { 352 int unit; 353 354 unit = devfs_clone_bitmap_get(&DEVFS_CLONE_BITMAP(bpf), 0); 355 ap->a_dev = make_only_dev(&bpf_ops, unit, 0, 0, 0600, "bpf%d", unit); 356 357 return 0; 358 } 359 360 /* 361 * Close the descriptor by detaching it from its interface, 362 * deallocating its buffers, and marking it free. 363 */ 364 /* ARGSUSED */ 365 static int 366 bpfclose(struct dev_close_args *ap) 367 { 368 cdev_t dev = ap->a_head.a_dev; 369 struct bpf_d *d = dev->si_drv1; 370 371 funsetown(d->bd_sigio); 372 crit_enter(); 373 if (d->bd_state == BPF_WAITING) 374 callout_stop(&d->bd_callout); 375 d->bd_state = BPF_IDLE; 376 if (d->bd_bif != NULL) 377 bpf_detachd(d); 378 crit_exit(); 379 bpf_freed(d); 380 dev->si_drv1 = NULL; 381 if (dev->si_uminor >= BPF_PREALLOCATED_UNITS) { 382 devfs_clone_bitmap_put(&DEVFS_CLONE_BITMAP(bpf), dev->si_uminor); 383 destroy_dev(dev); 384 } 385 kfree(d, M_BPF); 386 return(0); 387 } 388 389 /* 390 * Rotate the packet buffers in descriptor d. Move the store buffer 391 * into the hold slot, and the free buffer into the store slot. 392 * Zero the length of the new store buffer. 393 */ 394 #define ROTATE_BUFFERS(d) \ 395 (d)->bd_hbuf = (d)->bd_sbuf; \ 396 (d)->bd_hlen = (d)->bd_slen; \ 397 (d)->bd_sbuf = (d)->bd_fbuf; \ 398 (d)->bd_slen = 0; \ 399 (d)->bd_fbuf = NULL; 400 /* 401 * bpfread - read next chunk of packets from buffers 402 */ 403 static int 404 bpfread(struct dev_read_args *ap) 405 { 406 cdev_t dev = ap->a_head.a_dev; 407 struct bpf_d *d = dev->si_drv1; 408 int timed_out; 409 int error; 410 411 /* 412 * Restrict application to use a buffer the same size as 413 * as kernel buffers. 414 */ 415 if (ap->a_uio->uio_resid != d->bd_bufsize) 416 return(EINVAL); 417 418 crit_enter(); 419 if (d->bd_state == BPF_WAITING) 420 callout_stop(&d->bd_callout); 421 timed_out = (d->bd_state == BPF_TIMED_OUT); 422 d->bd_state = BPF_IDLE; 423 /* 424 * If the hold buffer is empty, then do a timed sleep, which 425 * ends when the timeout expires or when enough packets 426 * have arrived to fill the store buffer. 427 */ 428 while (d->bd_hbuf == NULL) { 429 if ((d->bd_immediate || (ap->a_ioflag & IO_NDELAY) || timed_out) 430 && d->bd_slen != 0) { 431 /* 432 * A packet(s) either arrived since the previous, 433 * We're in immediate mode, or are reading 434 * in non-blocking mode, and a packet(s) 435 * either arrived since the previous 436 * read or arrived while we were asleep. 437 * Rotate the buffers and return what's here. 438 */ 439 ROTATE_BUFFERS(d); 440 break; 441 } 442 443 /* 444 * No data is available, check to see if the bpf device 445 * is still pointed at a real interface. If not, return 446 * ENXIO so that the userland process knows to rebind 447 * it before using it again. 448 */ 449 if (d->bd_bif == NULL) { 450 crit_exit(); 451 return(ENXIO); 452 } 453 454 if (ap->a_ioflag & IO_NDELAY) { 455 crit_exit(); 456 return(EWOULDBLOCK); 457 } 458 error = tsleep(d, PCATCH, "bpf", d->bd_rtout); 459 if (error == EINTR || error == ERESTART) { 460 crit_exit(); 461 return(error); 462 } 463 if (error == EWOULDBLOCK) { 464 /* 465 * On a timeout, return what's in the buffer, 466 * which may be nothing. If there is something 467 * in the store buffer, we can rotate the buffers. 468 */ 469 if (d->bd_hbuf) 470 /* 471 * We filled up the buffer in between 472 * getting the timeout and arriving 473 * here, so we don't need to rotate. 474 */ 475 break; 476 477 if (d->bd_slen == 0) { 478 crit_exit(); 479 return(0); 480 } 481 ROTATE_BUFFERS(d); 482 break; 483 } 484 } 485 /* 486 * At this point, we know we have something in the hold slot. 487 */ 488 crit_exit(); 489 490 /* 491 * Move data from hold buffer into user space. 492 * We know the entire buffer is transferred since 493 * we checked above that the read buffer is bpf_bufsize bytes. 494 */ 495 error = uiomove(d->bd_hbuf, d->bd_hlen, ap->a_uio); 496 497 crit_enter(); 498 d->bd_fbuf = d->bd_hbuf; 499 d->bd_hbuf = NULL; 500 d->bd_hlen = 0; 501 crit_exit(); 502 503 return(error); 504 } 505 506 507 /* 508 * If there are processes sleeping on this descriptor, wake them up. 509 */ 510 static void 511 bpf_wakeup(struct bpf_d *d) 512 { 513 if (d->bd_state == BPF_WAITING) { 514 callout_stop(&d->bd_callout); 515 d->bd_state = BPF_IDLE; 516 } 517 wakeup(d); 518 if (d->bd_async && d->bd_sig && d->bd_sigio) 519 pgsigio(d->bd_sigio, d->bd_sig, 0); 520 521 get_mplock(); 522 selwakeup(&d->bd_sel); 523 rel_mplock(); 524 /* XXX */ 525 d->bd_sel.si_pid = 0; 526 } 527 528 static void 529 bpf_timed_out(void *arg) 530 { 531 struct bpf_d *d = (struct bpf_d *)arg; 532 533 crit_enter(); 534 if (d->bd_state == BPF_WAITING) { 535 d->bd_state = BPF_TIMED_OUT; 536 if (d->bd_slen != 0) 537 bpf_wakeup(d); 538 } 539 crit_exit(); 540 } 541 542 static void 543 bpf_output_dispatch(struct netmsg *nmsg) 544 { 545 struct netmsg_bpf_output *bmsg = (struct netmsg_bpf_output *)nmsg; 546 struct ifnet *ifp = bmsg->nm_ifp; 547 int error; 548 549 /* 550 * The driver frees the mbuf. 551 */ 552 error = ifp->if_output(ifp, bmsg->nm_mbuf, bmsg->nm_dst, NULL); 553 lwkt_replymsg(&nmsg->nm_lmsg, error); 554 } 555 556 static int 557 bpfwrite(struct dev_write_args *ap) 558 { 559 cdev_t dev = ap->a_head.a_dev; 560 struct bpf_d *d = dev->si_drv1; 561 struct ifnet *ifp; 562 struct mbuf *m; 563 int error; 564 struct sockaddr dst; 565 int datlen; 566 struct netmsg_bpf_output bmsg; 567 568 if (d->bd_bif == NULL) 569 return(ENXIO); 570 571 ifp = d->bd_bif->bif_ifp; 572 573 if (ap->a_uio->uio_resid == 0) 574 return(0); 575 576 error = bpf_movein(ap->a_uio, (int)d->bd_bif->bif_dlt, &m, 577 &dst, &datlen, d->bd_wfilter); 578 if (error) 579 return(error); 580 581 if (datlen > ifp->if_mtu) { 582 m_freem(m); 583 return(EMSGSIZE); 584 } 585 586 if (d->bd_hdrcmplt) 587 dst.sa_family = pseudo_AF_HDRCMPLT; 588 589 netmsg_init(&bmsg.nm_netmsg, NULL, &curthread->td_msgport, 590 MSGF_MPSAFE, bpf_output_dispatch); 591 bmsg.nm_mbuf = m; 592 bmsg.nm_ifp = ifp; 593 bmsg.nm_dst = &dst; 594 595 return lwkt_domsg(cpu_portfn(0), &bmsg.nm_netmsg.nm_lmsg, 0); 596 } 597 598 /* 599 * Reset a descriptor by flushing its packet buffer and clearing the 600 * receive and drop counts. Should be called at splimp. 601 */ 602 static void 603 bpf_resetd(struct bpf_d *d) 604 { 605 if (d->bd_hbuf) { 606 /* Free the hold buffer. */ 607 d->bd_fbuf = d->bd_hbuf; 608 d->bd_hbuf = NULL; 609 } 610 d->bd_slen = 0; 611 d->bd_hlen = 0; 612 d->bd_rcount = 0; 613 d->bd_dcount = 0; 614 } 615 616 /* 617 * FIONREAD Check for read packet available. 618 * SIOCGIFADDR Get interface address - convenient hook to driver. 619 * BIOCGBLEN Get buffer len [for read()]. 620 * BIOCSETF Set ethernet read filter. 621 * BIOCSETWF Set ethernet write filter. 622 * BIOCFLUSH Flush read packet buffer. 623 * BIOCPROMISC Put interface into promiscuous mode. 624 * BIOCGDLT Get link layer type. 625 * BIOCGETIF Get interface name. 626 * BIOCSETIF Set interface. 627 * BIOCSRTIMEOUT Set read timeout. 628 * BIOCGRTIMEOUT Get read timeout. 629 * BIOCGSTATS Get packet stats. 630 * BIOCIMMEDIATE Set immediate mode. 631 * BIOCVERSION Get filter language version. 632 * BIOCGHDRCMPLT Get "header already complete" flag 633 * BIOCSHDRCMPLT Set "header already complete" flag 634 * BIOCGSEESENT Get "see packets sent" flag 635 * BIOCSSEESENT Set "see packets sent" flag 636 * BIOCLOCK Set "locked" flag 637 */ 638 /* ARGSUSED */ 639 static int 640 bpfioctl(struct dev_ioctl_args *ap) 641 { 642 cdev_t dev = ap->a_head.a_dev; 643 struct bpf_d *d = dev->si_drv1; 644 int error = 0; 645 646 crit_enter(); 647 if (d->bd_state == BPF_WAITING) 648 callout_stop(&d->bd_callout); 649 d->bd_state = BPF_IDLE; 650 crit_exit(); 651 652 if (d->bd_locked == 1) { 653 switch (ap->a_cmd) { 654 case BIOCGBLEN: 655 case BIOCFLUSH: 656 case BIOCGDLT: 657 case BIOCGDLTLIST: 658 case BIOCGETIF: 659 case BIOCGRTIMEOUT: 660 case BIOCGSTATS: 661 case BIOCVERSION: 662 case BIOCGRSIG: 663 case BIOCGHDRCMPLT: 664 case FIONREAD: 665 case BIOCLOCK: 666 case BIOCSRTIMEOUT: 667 case BIOCIMMEDIATE: 668 case TIOCGPGRP: 669 break; 670 default: 671 return (EPERM); 672 } 673 } 674 switch (ap->a_cmd) { 675 default: 676 error = EINVAL; 677 break; 678 679 /* 680 * Check for read packet available. 681 */ 682 case FIONREAD: 683 { 684 int n; 685 686 crit_enter(); 687 n = d->bd_slen; 688 if (d->bd_hbuf) 689 n += d->bd_hlen; 690 crit_exit(); 691 692 *(int *)ap->a_data = n; 693 break; 694 } 695 696 case SIOCGIFADDR: 697 { 698 struct ifnet *ifp; 699 700 if (d->bd_bif == NULL) { 701 error = EINVAL; 702 } else { 703 ifp = d->bd_bif->bif_ifp; 704 ifnet_serialize_all(ifp); 705 error = ifp->if_ioctl(ifp, ap->a_cmd, 706 ap->a_data, ap->a_cred); 707 ifnet_deserialize_all(ifp); 708 } 709 break; 710 } 711 712 /* 713 * Get buffer len [for read()]. 714 */ 715 case BIOCGBLEN: 716 *(u_int *)ap->a_data = d->bd_bufsize; 717 break; 718 719 /* 720 * Set buffer length. 721 */ 722 case BIOCSBLEN: 723 if (d->bd_bif != NULL) { 724 error = EINVAL; 725 } else { 726 u_int size = *(u_int *)ap->a_data; 727 728 if (size > bpf_maxbufsize) 729 *(u_int *)ap->a_data = size = bpf_maxbufsize; 730 else if (size < BPF_MINBUFSIZE) 731 *(u_int *)ap->a_data = size = BPF_MINBUFSIZE; 732 d->bd_bufsize = size; 733 } 734 break; 735 736 /* 737 * Set link layer read filter. 738 */ 739 case BIOCSETF: 740 case BIOCSETWF: 741 error = bpf_setf(d, (struct bpf_program *)ap->a_data, 742 ap->a_cmd); 743 break; 744 745 /* 746 * Flush read packet buffer. 747 */ 748 case BIOCFLUSH: 749 crit_enter(); 750 bpf_resetd(d); 751 crit_exit(); 752 break; 753 754 /* 755 * Put interface into promiscuous mode. 756 */ 757 case BIOCPROMISC: 758 if (d->bd_bif == NULL) { 759 /* 760 * No interface attached yet. 761 */ 762 error = EINVAL; 763 break; 764 } 765 crit_enter(); 766 if (d->bd_promisc == 0) { 767 error = ifpromisc(d->bd_bif->bif_ifp, 1); 768 if (error == 0) 769 d->bd_promisc = 1; 770 } 771 crit_exit(); 772 break; 773 774 /* 775 * Get device parameters. 776 */ 777 case BIOCGDLT: 778 if (d->bd_bif == NULL) 779 error = EINVAL; 780 else 781 *(u_int *)ap->a_data = d->bd_bif->bif_dlt; 782 break; 783 784 /* 785 * Get a list of supported data link types. 786 */ 787 case BIOCGDLTLIST: 788 if (d->bd_bif == NULL) { 789 error = EINVAL; 790 } else { 791 error = bpf_getdltlist(d, 792 (struct bpf_dltlist *)ap->a_data); 793 } 794 break; 795 796 /* 797 * Set data link type. 798 */ 799 case BIOCSDLT: 800 if (d->bd_bif == NULL) 801 error = EINVAL; 802 else 803 error = bpf_setdlt(d, *(u_int *)ap->a_data); 804 break; 805 806 /* 807 * Get interface name. 808 */ 809 case BIOCGETIF: 810 if (d->bd_bif == NULL) { 811 error = EINVAL; 812 } else { 813 struct ifnet *const ifp = d->bd_bif->bif_ifp; 814 struct ifreq *const ifr = (struct ifreq *)ap->a_data; 815 816 strlcpy(ifr->ifr_name, ifp->if_xname, 817 sizeof ifr->ifr_name); 818 } 819 break; 820 821 /* 822 * Set interface. 823 */ 824 case BIOCSETIF: 825 error = bpf_setif(d, (struct ifreq *)ap->a_data); 826 break; 827 828 /* 829 * Set read timeout. 830 */ 831 case BIOCSRTIMEOUT: 832 { 833 struct timeval *tv = (struct timeval *)ap->a_data; 834 835 /* 836 * Subtract 1 tick from tvtohz() since this isn't 837 * a one-shot timer. 838 */ 839 if ((error = itimerfix(tv)) == 0) 840 d->bd_rtout = tvtohz_low(tv); 841 break; 842 } 843 844 /* 845 * Get read timeout. 846 */ 847 case BIOCGRTIMEOUT: 848 { 849 struct timeval *tv = (struct timeval *)ap->a_data; 850 851 tv->tv_sec = d->bd_rtout / hz; 852 tv->tv_usec = (d->bd_rtout % hz) * ustick; 853 break; 854 } 855 856 /* 857 * Get packet stats. 858 */ 859 case BIOCGSTATS: 860 { 861 struct bpf_stat *bs = (struct bpf_stat *)ap->a_data; 862 863 bs->bs_recv = d->bd_rcount; 864 bs->bs_drop = d->bd_dcount; 865 break; 866 } 867 868 /* 869 * Set immediate mode. 870 */ 871 case BIOCIMMEDIATE: 872 d->bd_immediate = *(u_int *)ap->a_data; 873 break; 874 875 case BIOCVERSION: 876 { 877 struct bpf_version *bv = (struct bpf_version *)ap->a_data; 878 879 bv->bv_major = BPF_MAJOR_VERSION; 880 bv->bv_minor = BPF_MINOR_VERSION; 881 break; 882 } 883 884 /* 885 * Get "header already complete" flag 886 */ 887 case BIOCGHDRCMPLT: 888 *(u_int *)ap->a_data = d->bd_hdrcmplt; 889 break; 890 891 /* 892 * Set "header already complete" flag 893 */ 894 case BIOCSHDRCMPLT: 895 d->bd_hdrcmplt = *(u_int *)ap->a_data ? 1 : 0; 896 break; 897 898 /* 899 * Get "see sent packets" flag 900 */ 901 case BIOCGSEESENT: 902 *(u_int *)ap->a_data = d->bd_seesent; 903 break; 904 905 /* 906 * Set "see sent packets" flag 907 */ 908 case BIOCSSEESENT: 909 d->bd_seesent = *(u_int *)ap->a_data; 910 break; 911 912 case FIOASYNC: /* Send signal on receive packets */ 913 d->bd_async = *(int *)ap->a_data; 914 break; 915 916 case FIOSETOWN: 917 error = fsetown(*(int *)ap->a_data, &d->bd_sigio); 918 break; 919 920 case FIOGETOWN: 921 *(int *)ap->a_data = fgetown(d->bd_sigio); 922 break; 923 924 /* This is deprecated, FIOSETOWN should be used instead. */ 925 case TIOCSPGRP: 926 error = fsetown(-(*(int *)ap->a_data), &d->bd_sigio); 927 break; 928 929 /* This is deprecated, FIOGETOWN should be used instead. */ 930 case TIOCGPGRP: 931 *(int *)ap->a_data = -fgetown(d->bd_sigio); 932 break; 933 934 case BIOCSRSIG: /* Set receive signal */ 935 { 936 u_int sig; 937 938 sig = *(u_int *)ap->a_data; 939 940 if (sig >= NSIG) 941 error = EINVAL; 942 else 943 d->bd_sig = sig; 944 break; 945 } 946 case BIOCGRSIG: 947 *(u_int *)ap->a_data = d->bd_sig; 948 break; 949 case BIOCLOCK: 950 d->bd_locked = 1; 951 break; 952 } 953 return(error); 954 } 955 956 /* 957 * Set d's packet filter program to fp. If this file already has a filter, 958 * free it and replace it. Returns EINVAL for bogus requests. 959 */ 960 static int 961 bpf_setf(struct bpf_d *d, struct bpf_program *fp, u_long cmd) 962 { 963 struct bpf_insn *fcode, *old; 964 u_int wfilter, flen, size; 965 966 if (cmd == BIOCSETWF) { 967 old = d->bd_wfilter; 968 wfilter = 1; 969 } else { 970 wfilter = 0; 971 old = d->bd_rfilter; 972 } 973 if (fp->bf_insns == NULL) { 974 if (fp->bf_len != 0) 975 return(EINVAL); 976 crit_enter(); 977 if (wfilter) 978 d->bd_wfilter = NULL; 979 else 980 d->bd_rfilter = NULL; 981 bpf_resetd(d); 982 crit_exit(); 983 if (old != NULL) 984 kfree(old, M_BPF); 985 return(0); 986 } 987 flen = fp->bf_len; 988 if (flen > BPF_MAXINSNS) 989 return(EINVAL); 990 991 size = flen * sizeof *fp->bf_insns; 992 fcode = (struct bpf_insn *)kmalloc(size, M_BPF, M_WAITOK); 993 if (copyin(fp->bf_insns, fcode, size) == 0 && 994 bpf_validate(fcode, (int)flen)) { 995 crit_enter(); 996 if (wfilter) 997 d->bd_wfilter = fcode; 998 else 999 d->bd_rfilter = fcode; 1000 bpf_resetd(d); 1001 crit_exit(); 1002 if (old != NULL) 1003 kfree(old, M_BPF); 1004 1005 return(0); 1006 } 1007 kfree(fcode, M_BPF); 1008 return(EINVAL); 1009 } 1010 1011 /* 1012 * Detach a file from its current interface (if attached at all) and attach 1013 * to the interface indicated by the name stored in ifr. 1014 * Return an errno or 0. 1015 */ 1016 static int 1017 bpf_setif(struct bpf_d *d, struct ifreq *ifr) 1018 { 1019 struct bpf_if *bp; 1020 int error; 1021 struct ifnet *theywant; 1022 1023 theywant = ifunit(ifr->ifr_name); 1024 if (theywant == NULL) 1025 return(ENXIO); 1026 1027 /* 1028 * Look through attached interfaces for the named one. 1029 */ 1030 for (bp = bpf_iflist; bp != NULL; bp = bp->bif_next) { 1031 struct ifnet *ifp = bp->bif_ifp; 1032 1033 if (ifp == NULL || ifp != theywant) 1034 continue; 1035 /* skip additional entry */ 1036 if (bp->bif_driverp != &ifp->if_bpf) 1037 continue; 1038 /* 1039 * We found the requested interface. 1040 * Allocate the packet buffers if we need to. 1041 * If we're already attached to requested interface, 1042 * just flush the buffer. 1043 */ 1044 if (d->bd_sbuf == NULL) { 1045 error = bpf_allocbufs(d); 1046 if (error != 0) 1047 return(error); 1048 } 1049 crit_enter(); 1050 if (bp != d->bd_bif) { 1051 if (d->bd_bif != NULL) { 1052 /* 1053 * Detach if attached to something else. 1054 */ 1055 bpf_detachd(d); 1056 } 1057 1058 bpf_attachd(d, bp); 1059 } 1060 bpf_resetd(d); 1061 crit_exit(); 1062 return(0); 1063 } 1064 1065 /* Not found. */ 1066 return(ENXIO); 1067 } 1068 1069 /* 1070 * Support for select() and poll() system calls 1071 * 1072 * Return true iff the specific operation will not block indefinitely. 1073 * Otherwise, return false but make a note that a selwakeup() must be done. 1074 */ 1075 static int 1076 bpfpoll(struct dev_poll_args *ap) 1077 { 1078 cdev_t dev = ap->a_head.a_dev; 1079 struct bpf_d *d; 1080 int revents; 1081 1082 d = dev->si_drv1; 1083 if (d->bd_bif == NULL) 1084 return(ENXIO); 1085 1086 revents = ap->a_events & (POLLOUT | POLLWRNORM); 1087 crit_enter(); 1088 if (ap->a_events & (POLLIN | POLLRDNORM)) { 1089 /* 1090 * An imitation of the FIONREAD ioctl code. 1091 * XXX not quite. An exact imitation: 1092 * if (d->b_slen != 0 || 1093 * (d->bd_hbuf != NULL && d->bd_hlen != 0) 1094 */ 1095 if (d->bd_hlen != 0 || 1096 ((d->bd_immediate || d->bd_state == BPF_TIMED_OUT) && 1097 d->bd_slen != 0)) { 1098 revents |= ap->a_events & (POLLIN | POLLRDNORM); 1099 } else { 1100 selrecord(curthread, &d->bd_sel); 1101 /* Start the read timeout if necessary. */ 1102 if (d->bd_rtout > 0 && d->bd_state == BPF_IDLE) { 1103 callout_reset(&d->bd_callout, d->bd_rtout, 1104 bpf_timed_out, d); 1105 d->bd_state = BPF_WAITING; 1106 } 1107 } 1108 } 1109 crit_exit(); 1110 ap->a_events = revents; 1111 return(0); 1112 } 1113 1114 /* 1115 * Process the packet pkt of length pktlen. The packet is parsed 1116 * by each listener's filter, and if accepted, stashed into the 1117 * corresponding buffer. 1118 */ 1119 void 1120 bpf_tap(struct bpf_if *bp, u_char *pkt, u_int pktlen) 1121 { 1122 struct bpf_d *d; 1123 struct timeval tv; 1124 int gottime = 0; 1125 u_int slen; 1126 1127 get_mplock(); 1128 1129 /* Re-check */ 1130 if (bp == NULL) { 1131 rel_mplock(); 1132 return; 1133 } 1134 1135 /* 1136 * Note that the ipl does not have to be raised at this point. 1137 * The only problem that could arise here is that if two different 1138 * interfaces shared any data. This is not the case. 1139 */ 1140 SLIST_FOREACH(d, &bp->bif_dlist, bd_next) { 1141 ++d->bd_rcount; 1142 slen = bpf_filter(d->bd_rfilter, pkt, pktlen, pktlen); 1143 if (slen != 0) { 1144 if (!gottime) { 1145 microtime(&tv); 1146 gottime = 1; 1147 } 1148 catchpacket(d, pkt, pktlen, slen, ovbcopy, &tv); 1149 } 1150 } 1151 1152 rel_mplock(); 1153 } 1154 1155 /* 1156 * Copy data from an mbuf chain into a buffer. This code is derived 1157 * from m_copydata in sys/uipc_mbuf.c. 1158 */ 1159 static void 1160 bpf_mcopy(const void *src_arg, void *dst_arg, size_t len) 1161 { 1162 const struct mbuf *m; 1163 u_int count; 1164 u_char *dst; 1165 1166 m = src_arg; 1167 dst = dst_arg; 1168 while (len > 0) { 1169 if (m == NULL) 1170 panic("bpf_mcopy"); 1171 count = min(m->m_len, len); 1172 bcopy(mtod(m, void *), dst, count); 1173 m = m->m_next; 1174 dst += count; 1175 len -= count; 1176 } 1177 } 1178 1179 /* 1180 * Process the packet in the mbuf chain m. The packet is parsed by each 1181 * listener's filter, and if accepted, stashed into the corresponding 1182 * buffer. 1183 */ 1184 void 1185 bpf_mtap(struct bpf_if *bp, struct mbuf *m) 1186 { 1187 struct bpf_d *d; 1188 u_int pktlen, slen; 1189 struct timeval tv; 1190 int gottime = 0; 1191 1192 get_mplock(); 1193 1194 /* Re-check */ 1195 if (bp == NULL) { 1196 rel_mplock(); 1197 return; 1198 } 1199 1200 /* Don't compute pktlen, if no descriptor is attached. */ 1201 if (SLIST_EMPTY(&bp->bif_dlist)) { 1202 rel_mplock(); 1203 return; 1204 } 1205 1206 pktlen = m_lengthm(m, NULL); 1207 1208 SLIST_FOREACH(d, &bp->bif_dlist, bd_next) { 1209 if (!d->bd_seesent && (m->m_pkthdr.rcvif == NULL)) 1210 continue; 1211 ++d->bd_rcount; 1212 slen = bpf_filter(d->bd_rfilter, (u_char *)m, pktlen, 0); 1213 if (slen != 0) { 1214 if (!gottime) { 1215 microtime(&tv); 1216 gottime = 1; 1217 } 1218 catchpacket(d, (u_char *)m, pktlen, slen, bpf_mcopy, 1219 &tv); 1220 } 1221 } 1222 1223 rel_mplock(); 1224 } 1225 1226 void 1227 bpf_mtap_family(struct bpf_if *bp, struct mbuf *m, sa_family_t family) 1228 { 1229 u_int family4; 1230 1231 KKASSERT(family != AF_UNSPEC); 1232 1233 family4 = (u_int)family; 1234 bpf_ptap(bp, m, &family4, sizeof(family4)); 1235 } 1236 1237 /* 1238 * Process the packet in the mbuf chain m with the header in m prepended. 1239 * The packet is parsed by each listener's filter, and if accepted, 1240 * stashed into the corresponding buffer. 1241 */ 1242 void 1243 bpf_ptap(struct bpf_if *bp, struct mbuf *m, const void *data, u_int dlen) 1244 { 1245 struct mbuf mb; 1246 1247 /* 1248 * Craft on-stack mbuf suitable for passing to bpf_mtap. 1249 * Note that we cut corners here; we only setup what's 1250 * absolutely needed--this mbuf should never go anywhere else. 1251 */ 1252 mb.m_next = m; 1253 mb.m_data = __DECONST(void *, data); /* LINTED */ 1254 mb.m_len = dlen; 1255 mb.m_pkthdr.rcvif = m->m_pkthdr.rcvif; 1256 1257 bpf_mtap(bp, &mb); 1258 } 1259 1260 /* 1261 * Move the packet data from interface memory (pkt) into the 1262 * store buffer. Return 1 if it's time to wakeup a listener (buffer full), 1263 * otherwise 0. "copy" is the routine called to do the actual data 1264 * transfer. bcopy is passed in to copy contiguous chunks, while 1265 * bpf_mcopy is passed in to copy mbuf chains. In the latter case, 1266 * pkt is really an mbuf. 1267 */ 1268 static void 1269 catchpacket(struct bpf_d *d, u_char *pkt, u_int pktlen, u_int snaplen, 1270 void (*cpfn)(const void *, void *, size_t), 1271 const struct timeval *tv) 1272 { 1273 struct bpf_hdr *hp; 1274 int totlen, curlen; 1275 int hdrlen = d->bd_bif->bif_hdrlen; 1276 /* 1277 * Figure out how many bytes to move. If the packet is 1278 * greater or equal to the snapshot length, transfer that 1279 * much. Otherwise, transfer the whole packet (unless 1280 * we hit the buffer size limit). 1281 */ 1282 totlen = hdrlen + min(snaplen, pktlen); 1283 if (totlen > d->bd_bufsize) 1284 totlen = d->bd_bufsize; 1285 1286 /* 1287 * Round up the end of the previous packet to the next longword. 1288 */ 1289 curlen = BPF_WORDALIGN(d->bd_slen); 1290 if (curlen + totlen > d->bd_bufsize) { 1291 /* 1292 * This packet will overflow the storage buffer. 1293 * Rotate the buffers if we can, then wakeup any 1294 * pending reads. 1295 */ 1296 if (d->bd_fbuf == NULL) { 1297 /* 1298 * We haven't completed the previous read yet, 1299 * so drop the packet. 1300 */ 1301 ++d->bd_dcount; 1302 return; 1303 } 1304 ROTATE_BUFFERS(d); 1305 bpf_wakeup(d); 1306 curlen = 0; 1307 } else if (d->bd_immediate || d->bd_state == BPF_TIMED_OUT) { 1308 /* 1309 * Immediate mode is set, or the read timeout has 1310 * already expired during a select call. A packet 1311 * arrived, so the reader should be woken up. 1312 */ 1313 bpf_wakeup(d); 1314 } 1315 1316 /* 1317 * Append the bpf header. 1318 */ 1319 hp = (struct bpf_hdr *)(d->bd_sbuf + curlen); 1320 hp->bh_tstamp = *tv; 1321 hp->bh_datalen = pktlen; 1322 hp->bh_hdrlen = hdrlen; 1323 /* 1324 * Copy the packet data into the store buffer and update its length. 1325 */ 1326 (*cpfn)(pkt, (u_char *)hp + hdrlen, (hp->bh_caplen = totlen - hdrlen)); 1327 d->bd_slen = curlen + totlen; 1328 } 1329 1330 /* 1331 * Initialize all nonzero fields of a descriptor. 1332 */ 1333 static int 1334 bpf_allocbufs(struct bpf_d *d) 1335 { 1336 d->bd_fbuf = kmalloc(d->bd_bufsize, M_BPF, M_WAITOK); 1337 d->bd_sbuf = kmalloc(d->bd_bufsize, M_BPF, M_WAITOK); 1338 d->bd_slen = 0; 1339 d->bd_hlen = 0; 1340 return(0); 1341 } 1342 1343 /* 1344 * Free buffers and packet filter program currently in use by a descriptor. 1345 * Called on close. 1346 */ 1347 static void 1348 bpf_freed(struct bpf_d *d) 1349 { 1350 /* 1351 * We don't need to lock out interrupts since this descriptor has 1352 * been detached from its interface and it yet hasn't been marked 1353 * free. 1354 */ 1355 if (d->bd_sbuf != NULL) { 1356 kfree(d->bd_sbuf, M_BPF); 1357 if (d->bd_hbuf != NULL) 1358 kfree(d->bd_hbuf, M_BPF); 1359 if (d->bd_fbuf != NULL) 1360 kfree(d->bd_fbuf, M_BPF); 1361 } 1362 if (d->bd_rfilter) 1363 kfree(d->bd_rfilter, M_BPF); 1364 if (d->bd_wfilter) 1365 kfree(d->bd_wfilter, M_BPF); 1366 } 1367 1368 /* 1369 * Attach an interface to bpf. ifp is a pointer to the structure 1370 * defining the interface to be attached, dlt is the link layer type, 1371 * and hdrlen is the fixed size of the link header (variable length 1372 * headers are not yet supported). 1373 */ 1374 void 1375 bpfattach(struct ifnet *ifp, u_int dlt, u_int hdrlen) 1376 { 1377 bpfattach_dlt(ifp, dlt, hdrlen, &ifp->if_bpf); 1378 } 1379 1380 void 1381 bpfattach_dlt(struct ifnet *ifp, u_int dlt, u_int hdrlen, struct bpf_if **driverp) 1382 { 1383 struct bpf_if *bp; 1384 1385 bp = kmalloc(sizeof *bp, M_BPF, M_WAITOK | M_ZERO); 1386 1387 SLIST_INIT(&bp->bif_dlist); 1388 bp->bif_ifp = ifp; 1389 bp->bif_dlt = dlt; 1390 bp->bif_driverp = driverp; 1391 *bp->bif_driverp = NULL; 1392 1393 bp->bif_next = bpf_iflist; 1394 bpf_iflist = bp; 1395 1396 /* 1397 * Compute the length of the bpf header. This is not necessarily 1398 * equal to SIZEOF_BPF_HDR because we want to insert spacing such 1399 * that the network layer header begins on a longword boundary (for 1400 * performance reasons and to alleviate alignment restrictions). 1401 */ 1402 bp->bif_hdrlen = BPF_WORDALIGN(hdrlen + SIZEOF_BPF_HDR) - hdrlen; 1403 1404 if (bootverbose) 1405 if_printf(ifp, "bpf attached\n"); 1406 } 1407 1408 /* 1409 * Detach bpf from an interface. This involves detaching each descriptor 1410 * associated with the interface, and leaving bd_bif NULL. Notify each 1411 * descriptor as it's detached so that any sleepers wake up and get 1412 * ENXIO. 1413 */ 1414 void 1415 bpfdetach(struct ifnet *ifp) 1416 { 1417 struct bpf_if *bp, *bp_prev; 1418 struct bpf_d *d; 1419 1420 crit_enter(); 1421 1422 /* Locate BPF interface information */ 1423 bp_prev = NULL; 1424 for (bp = bpf_iflist; bp != NULL; bp = bp->bif_next) { 1425 if (ifp == bp->bif_ifp) 1426 break; 1427 bp_prev = bp; 1428 } 1429 1430 /* Interface wasn't attached */ 1431 if (bp->bif_ifp == NULL) { 1432 crit_exit(); 1433 kprintf("bpfdetach: %s was not attached\n", ifp->if_xname); 1434 return; 1435 } 1436 1437 while ((d = SLIST_FIRST(&bp->bif_dlist)) != NULL) { 1438 bpf_detachd(d); 1439 bpf_wakeup(d); 1440 } 1441 1442 if (bp_prev != NULL) 1443 bp_prev->bif_next = bp->bif_next; 1444 else 1445 bpf_iflist = bp->bif_next; 1446 1447 kfree(bp, M_BPF); 1448 1449 crit_exit(); 1450 } 1451 1452 /* 1453 * Get a list of available data link type of the interface. 1454 */ 1455 static int 1456 bpf_getdltlist(struct bpf_d *d, 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 for (bp = bpf_iflist; bp != NULL; bp = bp->bif_next) { 1466 if (bp->bif_ifp != ifp) 1467 continue; 1468 if (bfl->bfl_list != NULL) { 1469 if (n >= bfl->bfl_len) { 1470 return (ENOMEM); 1471 } 1472 error = copyout(&bp->bif_dlt, 1473 bfl->bfl_list + n, sizeof(u_int)); 1474 } 1475 n++; 1476 } 1477 bfl->bfl_len = n; 1478 return(error); 1479 } 1480 1481 /* 1482 * Set the data link type of a BPF instance. 1483 */ 1484 static int 1485 bpf_setdlt(struct bpf_d *d, u_int dlt) 1486 { 1487 int error, opromisc; 1488 struct ifnet *ifp; 1489 struct bpf_if *bp; 1490 1491 if (d->bd_bif->bif_dlt == dlt) 1492 return (0); 1493 ifp = d->bd_bif->bif_ifp; 1494 for (bp = bpf_iflist; bp != NULL; bp = bp->bif_next) { 1495 if (bp->bif_ifp == ifp && bp->bif_dlt == dlt) 1496 break; 1497 } 1498 if (bp != NULL) { 1499 opromisc = d->bd_promisc; 1500 crit_enter(); 1501 bpf_detachd(d); 1502 bpf_attachd(d, bp); 1503 bpf_resetd(d); 1504 if (opromisc) { 1505 error = ifpromisc(bp->bif_ifp, 1); 1506 if (error) { 1507 if_printf(bp->bif_ifp, 1508 "bpf_setdlt: ifpromisc failed (%d)\n", 1509 error); 1510 } else { 1511 d->bd_promisc = 1; 1512 } 1513 } 1514 crit_exit(); 1515 } 1516 return(bp == NULL ? EINVAL : 0); 1517 } 1518 1519 static void 1520 bpf_drvinit(void *unused) 1521 { 1522 int i; 1523 1524 make_autoclone_dev(&bpf_ops, &DEVFS_CLONE_BITMAP(bpf), 1525 bpfclone, 0, 0, 0600, "bpf"); 1526 for (i = 0; i < BPF_PREALLOCATED_UNITS; i++) { 1527 make_dev(&bpf_ops, i, 0, 0, 0600, "bpf%d", i); 1528 devfs_clone_bitmap_set(&DEVFS_CLONE_BITMAP(bpf), i); 1529 } 1530 } 1531 1532 static void 1533 bpf_drvuninit(void *unused) 1534 { 1535 devfs_clone_handler_del("bpf"); 1536 dev_ops_remove_all(&bpf_ops); 1537 devfs_clone_bitmap_uninit(&DEVFS_CLONE_BITMAP(bpf)); 1538 } 1539 1540 SYSINIT(bpfdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,bpf_drvinit,NULL) 1541 SYSUNINIT(bpfdev, SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,bpf_drvuninit, NULL); 1542 1543 #else /* !BPF */ 1544 /* 1545 * NOP stubs to allow bpf-using drivers to load and function. 1546 * 1547 * A 'better' implementation would allow the core bpf functionality 1548 * to be loaded at runtime. 1549 */ 1550 1551 void 1552 bpf_tap(struct bpf_if *bp, u_char *pkt, u_int pktlen) 1553 { 1554 } 1555 1556 void 1557 bpf_mtap(struct bpf_if *bp, struct mbuf *m) 1558 { 1559 } 1560 1561 void 1562 bpf_ptap(struct bpf_if *bp, struct mbuf *m, const void *data, u_int dlen) 1563 { 1564 } 1565 1566 void 1567 bpfattach(struct ifnet *ifp, u_int dlt, u_int hdrlen) 1568 { 1569 } 1570 1571 void 1572 bpfattach_dlt(struct ifnet *ifp, u_int dlt, u_int hdrlen, struct bpf_if **driverp) 1573 { 1574 } 1575 1576 void 1577 bpfdetach(struct ifnet *ifp) 1578 { 1579 } 1580 1581 u_int 1582 bpf_filter(const struct bpf_insn *pc, u_char *p, u_int wirelen, u_int buflen) 1583 { 1584 return -1; /* "no filter" behaviour */ 1585 } 1586 1587 #endif /* !BPF */ 1588