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 } 269 270 /* 271 * Detach a file from its interface. 272 */ 273 static void 274 bpf_detachd(struct bpf_d *d) 275 { 276 int error; 277 struct bpf_if *bp; 278 struct ifnet *ifp; 279 280 bp = d->bd_bif; 281 ifp = bp->bif_ifp; 282 283 /* Remove d from the interface's descriptor list. */ 284 SLIST_REMOVE(&bp->bif_dlist, d, bpf_d, bd_next); 285 286 if (SLIST_EMPTY(&bp->bif_dlist)) { 287 /* 288 * Let the driver know that there are no more listeners. 289 */ 290 *bp->bif_driverp = NULL; 291 } 292 d->bd_bif = NULL; 293 /* 294 * Check if this descriptor had requested promiscuous mode. 295 * If so, turn it off. 296 */ 297 if (d->bd_promisc) { 298 d->bd_promisc = 0; 299 error = ifpromisc(ifp, 0); 300 if (error != 0 && error != ENXIO) { 301 /* 302 * ENXIO can happen if a pccard is unplugged, 303 * Something is really wrong if we were able to put 304 * the driver into promiscuous mode, but can't 305 * take it out. 306 */ 307 if_printf(ifp, "bpf_detach: ifpromisc failed(%d)\n", 308 error); 309 } 310 } 311 } 312 313 /* 314 * Open ethernet device. Returns ENXIO for illegal minor device number, 315 * EBUSY if file is open by another process. 316 */ 317 /* ARGSUSED */ 318 static int 319 bpfopen(struct dev_open_args *ap) 320 { 321 cdev_t dev = ap->a_head.a_dev; 322 struct bpf_d *d; 323 324 if (ap->a_cred->cr_prison) 325 return(EPERM); 326 327 d = dev->si_drv1; 328 /* 329 * Each minor can be opened by only one process. If the requested 330 * minor is in use, return EBUSY. 331 */ 332 if (d != NULL) 333 return(EBUSY); 334 335 MALLOC(d, struct bpf_d *, sizeof *d, M_BPF, M_WAITOK | M_ZERO); 336 dev->si_drv1 = d; 337 d->bd_bufsize = bpf_bufsize; 338 d->bd_sig = SIGIO; 339 d->bd_seesent = 1; 340 callout_init(&d->bd_callout); 341 return(0); 342 } 343 344 static int 345 bpfclone(struct dev_clone_args *ap) 346 { 347 int unit; 348 349 unit = devfs_clone_bitmap_get(&DEVFS_CLONE_BITMAP(bpf), 0); 350 ap->a_dev = make_only_dev(&bpf_ops, unit, 0, 0, 0600, "bpf%d", unit); 351 352 return 0; 353 } 354 355 /* 356 * Close the descriptor by detaching it from its interface, 357 * deallocating its buffers, and marking it free. 358 */ 359 /* ARGSUSED */ 360 static int 361 bpfclose(struct dev_close_args *ap) 362 { 363 cdev_t dev = ap->a_head.a_dev; 364 struct bpf_d *d = dev->si_drv1; 365 366 funsetown(d->bd_sigio); 367 crit_enter(); 368 if (d->bd_state == BPF_WAITING) 369 callout_stop(&d->bd_callout); 370 d->bd_state = BPF_IDLE; 371 if (d->bd_bif != NULL) 372 bpf_detachd(d); 373 crit_exit(); 374 bpf_freed(d); 375 dev->si_drv1 = NULL; 376 if (dev->si_uminor >= BPF_PREALLOCATED_UNITS) { 377 devfs_clone_bitmap_put(&DEVFS_CLONE_BITMAP(bpf), dev->si_uminor); 378 destroy_dev(dev); 379 } 380 kfree(d, M_BPF); 381 return(0); 382 } 383 384 /* 385 * Rotate the packet buffers in descriptor d. Move the store buffer 386 * into the hold slot, and the free buffer into the store slot. 387 * Zero the length of the new store buffer. 388 */ 389 #define ROTATE_BUFFERS(d) \ 390 (d)->bd_hbuf = (d)->bd_sbuf; \ 391 (d)->bd_hlen = (d)->bd_slen; \ 392 (d)->bd_sbuf = (d)->bd_fbuf; \ 393 (d)->bd_slen = 0; \ 394 (d)->bd_fbuf = NULL; 395 /* 396 * bpfread - read next chunk of packets from buffers 397 */ 398 static int 399 bpfread(struct dev_read_args *ap) 400 { 401 cdev_t dev = ap->a_head.a_dev; 402 struct bpf_d *d = dev->si_drv1; 403 int timed_out; 404 int error; 405 406 /* 407 * Restrict application to use a buffer the same size as 408 * as kernel buffers. 409 */ 410 if (ap->a_uio->uio_resid != d->bd_bufsize) 411 return(EINVAL); 412 413 crit_enter(); 414 if (d->bd_state == BPF_WAITING) 415 callout_stop(&d->bd_callout); 416 timed_out = (d->bd_state == BPF_TIMED_OUT); 417 d->bd_state = BPF_IDLE; 418 /* 419 * If the hold buffer is empty, then do a timed sleep, which 420 * ends when the timeout expires or when enough packets 421 * have arrived to fill the store buffer. 422 */ 423 while (d->bd_hbuf == NULL) { 424 if ((d->bd_immediate || (ap->a_ioflag & IO_NDELAY) || timed_out) 425 && d->bd_slen != 0) { 426 /* 427 * A packet(s) either arrived since the previous, 428 * We're in immediate mode, or are reading 429 * in non-blocking mode, and a packet(s) 430 * either arrived since the previous 431 * read or arrived while we were asleep. 432 * Rotate the buffers and return what's here. 433 */ 434 ROTATE_BUFFERS(d); 435 break; 436 } 437 438 /* 439 * No data is available, check to see if the bpf device 440 * is still pointed at a real interface. If not, return 441 * ENXIO so that the userland process knows to rebind 442 * it before using it again. 443 */ 444 if (d->bd_bif == NULL) { 445 crit_exit(); 446 return(ENXIO); 447 } 448 449 if (ap->a_ioflag & IO_NDELAY) { 450 crit_exit(); 451 return(EWOULDBLOCK); 452 } 453 error = tsleep(d, PCATCH, "bpf", d->bd_rtout); 454 if (error == EINTR || error == ERESTART) { 455 crit_exit(); 456 return(error); 457 } 458 if (error == EWOULDBLOCK) { 459 /* 460 * On a timeout, return what's in the buffer, 461 * which may be nothing. If there is something 462 * in the store buffer, we can rotate the buffers. 463 */ 464 if (d->bd_hbuf) 465 /* 466 * We filled up the buffer in between 467 * getting the timeout and arriving 468 * here, so we don't need to rotate. 469 */ 470 break; 471 472 if (d->bd_slen == 0) { 473 crit_exit(); 474 return(0); 475 } 476 ROTATE_BUFFERS(d); 477 break; 478 } 479 } 480 /* 481 * At this point, we know we have something in the hold slot. 482 */ 483 crit_exit(); 484 485 /* 486 * Move data from hold buffer into user space. 487 * We know the entire buffer is transferred since 488 * we checked above that the read buffer is bpf_bufsize bytes. 489 */ 490 error = uiomove(d->bd_hbuf, d->bd_hlen, ap->a_uio); 491 492 crit_enter(); 493 d->bd_fbuf = d->bd_hbuf; 494 d->bd_hbuf = NULL; 495 d->bd_hlen = 0; 496 crit_exit(); 497 498 return(error); 499 } 500 501 502 /* 503 * If there are processes sleeping on this descriptor, wake them up. 504 */ 505 static void 506 bpf_wakeup(struct bpf_d *d) 507 { 508 if (d->bd_state == BPF_WAITING) { 509 callout_stop(&d->bd_callout); 510 d->bd_state = BPF_IDLE; 511 } 512 wakeup(d); 513 if (d->bd_async && d->bd_sig && d->bd_sigio) 514 pgsigio(d->bd_sigio, d->bd_sig, 0); 515 516 get_mplock(); 517 selwakeup(&d->bd_sel); 518 rel_mplock(); 519 /* XXX */ 520 d->bd_sel.si_pid = 0; 521 } 522 523 static void 524 bpf_timed_out(void *arg) 525 { 526 struct bpf_d *d = (struct bpf_d *)arg; 527 528 crit_enter(); 529 if (d->bd_state == BPF_WAITING) { 530 d->bd_state = BPF_TIMED_OUT; 531 if (d->bd_slen != 0) 532 bpf_wakeup(d); 533 } 534 crit_exit(); 535 } 536 537 static void 538 bpf_output_dispatch(struct netmsg *nmsg) 539 { 540 struct netmsg_bpf_output *bmsg = (struct netmsg_bpf_output *)nmsg; 541 struct ifnet *ifp = bmsg->nm_ifp; 542 int error; 543 544 /* 545 * The driver frees the mbuf. 546 */ 547 error = ifp->if_output(ifp, bmsg->nm_mbuf, bmsg->nm_dst, NULL); 548 lwkt_replymsg(&nmsg->nm_lmsg, error); 549 } 550 551 static int 552 bpfwrite(struct dev_write_args *ap) 553 { 554 cdev_t dev = ap->a_head.a_dev; 555 struct bpf_d *d = dev->si_drv1; 556 struct ifnet *ifp; 557 struct mbuf *m; 558 int error; 559 struct sockaddr dst; 560 int datlen; 561 struct netmsg_bpf_output bmsg; 562 563 if (d->bd_bif == NULL) 564 return(ENXIO); 565 566 ifp = d->bd_bif->bif_ifp; 567 568 if (ap->a_uio->uio_resid == 0) 569 return(0); 570 571 error = bpf_movein(ap->a_uio, (int)d->bd_bif->bif_dlt, &m, 572 &dst, &datlen, d->bd_wfilter); 573 if (error) 574 return(error); 575 576 if (datlen > ifp->if_mtu) { 577 m_freem(m); 578 return(EMSGSIZE); 579 } 580 581 if (d->bd_hdrcmplt) 582 dst.sa_family = pseudo_AF_HDRCMPLT; 583 584 netmsg_init(&bmsg.nm_netmsg, NULL, &curthread->td_msgport, 585 MSGF_MPSAFE, bpf_output_dispatch); 586 bmsg.nm_mbuf = m; 587 bmsg.nm_ifp = ifp; 588 bmsg.nm_dst = &dst; 589 590 return lwkt_domsg(cpu_portfn(0), &bmsg.nm_netmsg.nm_lmsg, 0); 591 } 592 593 /* 594 * Reset a descriptor by flushing its packet buffer and clearing the 595 * receive and drop counts. Should be called at splimp. 596 */ 597 static void 598 bpf_resetd(struct bpf_d *d) 599 { 600 if (d->bd_hbuf) { 601 /* Free the hold buffer. */ 602 d->bd_fbuf = d->bd_hbuf; 603 d->bd_hbuf = NULL; 604 } 605 d->bd_slen = 0; 606 d->bd_hlen = 0; 607 d->bd_rcount = 0; 608 d->bd_dcount = 0; 609 } 610 611 /* 612 * FIONREAD Check for read packet available. 613 * SIOCGIFADDR Get interface address - convenient hook to driver. 614 * BIOCGBLEN Get buffer len [for read()]. 615 * BIOCSETF Set ethernet read filter. 616 * BIOCSETWF Set ethernet write filter. 617 * BIOCFLUSH Flush read packet buffer. 618 * BIOCPROMISC Put interface into promiscuous mode. 619 * BIOCGDLT Get link layer type. 620 * BIOCGETIF Get interface name. 621 * BIOCSETIF Set interface. 622 * BIOCSRTIMEOUT Set read timeout. 623 * BIOCGRTIMEOUT Get read timeout. 624 * BIOCGSTATS Get packet stats. 625 * BIOCIMMEDIATE Set immediate mode. 626 * BIOCVERSION Get filter language version. 627 * BIOCGHDRCMPLT Get "header already complete" flag 628 * BIOCSHDRCMPLT Set "header already complete" flag 629 * BIOCGSEESENT Get "see packets sent" flag 630 * BIOCSSEESENT Set "see packets sent" flag 631 * BIOCLOCK Set "locked" flag 632 */ 633 /* ARGSUSED */ 634 static int 635 bpfioctl(struct dev_ioctl_args *ap) 636 { 637 cdev_t dev = ap->a_head.a_dev; 638 struct bpf_d *d = dev->si_drv1; 639 int error = 0; 640 641 crit_enter(); 642 if (d->bd_state == BPF_WAITING) 643 callout_stop(&d->bd_callout); 644 d->bd_state = BPF_IDLE; 645 crit_exit(); 646 647 if (d->bd_locked == 1) { 648 switch (ap->a_cmd) { 649 case BIOCGBLEN: 650 case BIOCFLUSH: 651 case BIOCGDLT: 652 case BIOCGDLTLIST: 653 case BIOCGETIF: 654 case BIOCGRTIMEOUT: 655 case BIOCGSTATS: 656 case BIOCVERSION: 657 case BIOCGRSIG: 658 case BIOCGHDRCMPLT: 659 case FIONREAD: 660 case BIOCLOCK: 661 case BIOCSRTIMEOUT: 662 case BIOCIMMEDIATE: 663 case TIOCGPGRP: 664 break; 665 default: 666 return (EPERM); 667 } 668 } 669 switch (ap->a_cmd) { 670 default: 671 error = EINVAL; 672 break; 673 674 /* 675 * Check for read packet available. 676 */ 677 case FIONREAD: 678 { 679 int n; 680 681 crit_enter(); 682 n = d->bd_slen; 683 if (d->bd_hbuf) 684 n += d->bd_hlen; 685 crit_exit(); 686 687 *(int *)ap->a_data = n; 688 break; 689 } 690 691 case SIOCGIFADDR: 692 { 693 struct ifnet *ifp; 694 695 if (d->bd_bif == NULL) { 696 error = EINVAL; 697 } else { 698 ifp = d->bd_bif->bif_ifp; 699 ifnet_serialize_all(ifp); 700 error = ifp->if_ioctl(ifp, ap->a_cmd, 701 ap->a_data, ap->a_cred); 702 ifnet_deserialize_all(ifp); 703 } 704 break; 705 } 706 707 /* 708 * Get buffer len [for read()]. 709 */ 710 case BIOCGBLEN: 711 *(u_int *)ap->a_data = d->bd_bufsize; 712 break; 713 714 /* 715 * Set buffer length. 716 */ 717 case BIOCSBLEN: 718 if (d->bd_bif != NULL) { 719 error = EINVAL; 720 } else { 721 u_int size = *(u_int *)ap->a_data; 722 723 if (size > bpf_maxbufsize) 724 *(u_int *)ap->a_data = size = bpf_maxbufsize; 725 else if (size < BPF_MINBUFSIZE) 726 *(u_int *)ap->a_data = size = BPF_MINBUFSIZE; 727 d->bd_bufsize = size; 728 } 729 break; 730 731 /* 732 * Set link layer read filter. 733 */ 734 case BIOCSETF: 735 case BIOCSETWF: 736 error = bpf_setf(d, (struct bpf_program *)ap->a_data, 737 ap->a_cmd); 738 break; 739 740 /* 741 * Flush read packet buffer. 742 */ 743 case BIOCFLUSH: 744 crit_enter(); 745 bpf_resetd(d); 746 crit_exit(); 747 break; 748 749 /* 750 * Put interface into promiscuous mode. 751 */ 752 case BIOCPROMISC: 753 if (d->bd_bif == NULL) { 754 /* 755 * No interface attached yet. 756 */ 757 error = EINVAL; 758 break; 759 } 760 crit_enter(); 761 if (d->bd_promisc == 0) { 762 error = ifpromisc(d->bd_bif->bif_ifp, 1); 763 if (error == 0) 764 d->bd_promisc = 1; 765 } 766 crit_exit(); 767 break; 768 769 /* 770 * Get device parameters. 771 */ 772 case BIOCGDLT: 773 if (d->bd_bif == NULL) 774 error = EINVAL; 775 else 776 *(u_int *)ap->a_data = d->bd_bif->bif_dlt; 777 break; 778 779 /* 780 * Get a list of supported data link types. 781 */ 782 case BIOCGDLTLIST: 783 if (d->bd_bif == NULL) { 784 error = EINVAL; 785 } else { 786 error = bpf_getdltlist(d, 787 (struct bpf_dltlist *)ap->a_data); 788 } 789 break; 790 791 /* 792 * Set data link type. 793 */ 794 case BIOCSDLT: 795 if (d->bd_bif == NULL) 796 error = EINVAL; 797 else 798 error = bpf_setdlt(d, *(u_int *)ap->a_data); 799 break; 800 801 /* 802 * Get interface name. 803 */ 804 case BIOCGETIF: 805 if (d->bd_bif == NULL) { 806 error = EINVAL; 807 } else { 808 struct ifnet *const ifp = d->bd_bif->bif_ifp; 809 struct ifreq *const ifr = (struct ifreq *)ap->a_data; 810 811 strlcpy(ifr->ifr_name, ifp->if_xname, 812 sizeof ifr->ifr_name); 813 } 814 break; 815 816 /* 817 * Set interface. 818 */ 819 case BIOCSETIF: 820 error = bpf_setif(d, (struct ifreq *)ap->a_data); 821 break; 822 823 /* 824 * Set read timeout. 825 */ 826 case BIOCSRTIMEOUT: 827 { 828 struct timeval *tv = (struct timeval *)ap->a_data; 829 830 /* 831 * Subtract 1 tick from tvtohz() since this isn't 832 * a one-shot timer. 833 */ 834 if ((error = itimerfix(tv)) == 0) 835 d->bd_rtout = tvtohz_low(tv); 836 break; 837 } 838 839 /* 840 * Get read timeout. 841 */ 842 case BIOCGRTIMEOUT: 843 { 844 struct timeval *tv = (struct timeval *)ap->a_data; 845 846 tv->tv_sec = d->bd_rtout / hz; 847 tv->tv_usec = (d->bd_rtout % hz) * ustick; 848 break; 849 } 850 851 /* 852 * Get packet stats. 853 */ 854 case BIOCGSTATS: 855 { 856 struct bpf_stat *bs = (struct bpf_stat *)ap->a_data; 857 858 bs->bs_recv = d->bd_rcount; 859 bs->bs_drop = d->bd_dcount; 860 break; 861 } 862 863 /* 864 * Set immediate mode. 865 */ 866 case BIOCIMMEDIATE: 867 d->bd_immediate = *(u_int *)ap->a_data; 868 break; 869 870 case BIOCVERSION: 871 { 872 struct bpf_version *bv = (struct bpf_version *)ap->a_data; 873 874 bv->bv_major = BPF_MAJOR_VERSION; 875 bv->bv_minor = BPF_MINOR_VERSION; 876 break; 877 } 878 879 /* 880 * Get "header already complete" flag 881 */ 882 case BIOCGHDRCMPLT: 883 *(u_int *)ap->a_data = d->bd_hdrcmplt; 884 break; 885 886 /* 887 * Set "header already complete" flag 888 */ 889 case BIOCSHDRCMPLT: 890 d->bd_hdrcmplt = *(u_int *)ap->a_data ? 1 : 0; 891 break; 892 893 /* 894 * Get "see sent packets" flag 895 */ 896 case BIOCGSEESENT: 897 *(u_int *)ap->a_data = d->bd_seesent; 898 break; 899 900 /* 901 * Set "see sent packets" flag 902 */ 903 case BIOCSSEESENT: 904 d->bd_seesent = *(u_int *)ap->a_data; 905 break; 906 907 case FIOASYNC: /* Send signal on receive packets */ 908 d->bd_async = *(int *)ap->a_data; 909 break; 910 911 case FIOSETOWN: 912 error = fsetown(*(int *)ap->a_data, &d->bd_sigio); 913 break; 914 915 case FIOGETOWN: 916 *(int *)ap->a_data = fgetown(d->bd_sigio); 917 break; 918 919 /* This is deprecated, FIOSETOWN should be used instead. */ 920 case TIOCSPGRP: 921 error = fsetown(-(*(int *)ap->a_data), &d->bd_sigio); 922 break; 923 924 /* This is deprecated, FIOGETOWN should be used instead. */ 925 case TIOCGPGRP: 926 *(int *)ap->a_data = -fgetown(d->bd_sigio); 927 break; 928 929 case BIOCSRSIG: /* Set receive signal */ 930 { 931 u_int sig; 932 933 sig = *(u_int *)ap->a_data; 934 935 if (sig >= NSIG) 936 error = EINVAL; 937 else 938 d->bd_sig = sig; 939 break; 940 } 941 case BIOCGRSIG: 942 *(u_int *)ap->a_data = d->bd_sig; 943 break; 944 case BIOCLOCK: 945 d->bd_locked = 1; 946 break; 947 } 948 return(error); 949 } 950 951 /* 952 * Set d's packet filter program to fp. If this file already has a filter, 953 * free it and replace it. Returns EINVAL for bogus requests. 954 */ 955 static int 956 bpf_setf(struct bpf_d *d, struct bpf_program *fp, u_long cmd) 957 { 958 struct bpf_insn *fcode, *old; 959 u_int wfilter, flen, size; 960 961 if (cmd == BIOCSETWF) { 962 old = d->bd_wfilter; 963 wfilter = 1; 964 } else { 965 wfilter = 0; 966 old = d->bd_rfilter; 967 } 968 if (fp->bf_insns == NULL) { 969 if (fp->bf_len != 0) 970 return(EINVAL); 971 crit_enter(); 972 if (wfilter) 973 d->bd_wfilter = NULL; 974 else 975 d->bd_rfilter = NULL; 976 bpf_resetd(d); 977 crit_exit(); 978 if (old != NULL) 979 kfree(old, M_BPF); 980 return(0); 981 } 982 flen = fp->bf_len; 983 if (flen > BPF_MAXINSNS) 984 return(EINVAL); 985 986 size = flen * sizeof *fp->bf_insns; 987 fcode = (struct bpf_insn *)kmalloc(size, M_BPF, M_WAITOK); 988 if (copyin(fp->bf_insns, fcode, size) == 0 && 989 bpf_validate(fcode, (int)flen)) { 990 crit_enter(); 991 if (wfilter) 992 d->bd_wfilter = fcode; 993 else 994 d->bd_rfilter = fcode; 995 bpf_resetd(d); 996 crit_exit(); 997 if (old != NULL) 998 kfree(old, M_BPF); 999 1000 return(0); 1001 } 1002 kfree(fcode, M_BPF); 1003 return(EINVAL); 1004 } 1005 1006 /* 1007 * Detach a file from its current interface (if attached at all) and attach 1008 * to the interface indicated by the name stored in ifr. 1009 * Return an errno or 0. 1010 */ 1011 static int 1012 bpf_setif(struct bpf_d *d, struct ifreq *ifr) 1013 { 1014 struct bpf_if *bp; 1015 int error; 1016 struct ifnet *theywant; 1017 1018 theywant = ifunit(ifr->ifr_name); 1019 if (theywant == NULL) 1020 return(ENXIO); 1021 1022 /* 1023 * Look through attached interfaces for the named one. 1024 */ 1025 for (bp = bpf_iflist; bp != NULL; bp = bp->bif_next) { 1026 struct ifnet *ifp = bp->bif_ifp; 1027 1028 if (ifp == NULL || ifp != theywant) 1029 continue; 1030 /* skip additional entry */ 1031 if (bp->bif_driverp != &ifp->if_bpf) 1032 continue; 1033 /* 1034 * We found the requested interface. 1035 * If it's not up, return an error. 1036 * Allocate the packet buffers if we need to. 1037 * If we're already attached to requested interface, 1038 * just flush the buffer. 1039 */ 1040 if (!(ifp->if_flags & IFF_UP)) 1041 return(ENETDOWN); 1042 1043 if (d->bd_sbuf == NULL) { 1044 error = bpf_allocbufs(d); 1045 if (error != 0) 1046 return(error); 1047 } 1048 crit_enter(); 1049 if (bp != d->bd_bif) { 1050 if (d->bd_bif != NULL) { 1051 /* 1052 * Detach if attached to something else. 1053 */ 1054 bpf_detachd(d); 1055 } 1056 1057 bpf_attachd(d, bp); 1058 } 1059 bpf_resetd(d); 1060 crit_exit(); 1061 return(0); 1062 } 1063 1064 /* Not found. */ 1065 return(ENXIO); 1066 } 1067 1068 /* 1069 * Support for select() and poll() system calls 1070 * 1071 * Return true iff the specific operation will not block indefinitely. 1072 * Otherwise, return false but make a note that a selwakeup() must be done. 1073 */ 1074 static int 1075 bpfpoll(struct dev_poll_args *ap) 1076 { 1077 cdev_t dev = ap->a_head.a_dev; 1078 struct bpf_d *d; 1079 int revents; 1080 1081 d = dev->si_drv1; 1082 if (d->bd_bif == NULL) 1083 return(ENXIO); 1084 1085 revents = ap->a_events & (POLLOUT | POLLWRNORM); 1086 crit_enter(); 1087 if (ap->a_events & (POLLIN | POLLRDNORM)) { 1088 /* 1089 * An imitation of the FIONREAD ioctl code. 1090 * XXX not quite. An exact imitation: 1091 * if (d->b_slen != 0 || 1092 * (d->bd_hbuf != NULL && d->bd_hlen != 0) 1093 */ 1094 if (d->bd_hlen != 0 || 1095 ((d->bd_immediate || d->bd_state == BPF_TIMED_OUT) && 1096 d->bd_slen != 0)) { 1097 revents |= ap->a_events & (POLLIN | POLLRDNORM); 1098 } else { 1099 selrecord(curthread, &d->bd_sel); 1100 /* Start the read timeout if necessary. */ 1101 if (d->bd_rtout > 0 && d->bd_state == BPF_IDLE) { 1102 callout_reset(&d->bd_callout, d->bd_rtout, 1103 bpf_timed_out, d); 1104 d->bd_state = BPF_WAITING; 1105 } 1106 } 1107 } 1108 crit_exit(); 1109 ap->a_events = revents; 1110 return(0); 1111 } 1112 1113 /* 1114 * Process the packet pkt of length pktlen. The packet is parsed 1115 * by each listener's filter, and if accepted, stashed into the 1116 * corresponding buffer. 1117 */ 1118 void 1119 bpf_tap(struct bpf_if *bp, u_char *pkt, u_int pktlen) 1120 { 1121 struct bpf_d *d; 1122 struct timeval tv; 1123 int gottime = 0; 1124 u_int slen; 1125 1126 get_mplock(); 1127 1128 /* Re-check */ 1129 if (bp == NULL) { 1130 rel_mplock(); 1131 return; 1132 } 1133 1134 /* 1135 * Note that the ipl does not have to be raised at this point. 1136 * The only problem that could arise here is that if two different 1137 * interfaces shared any data. This is not the case. 1138 */ 1139 SLIST_FOREACH(d, &bp->bif_dlist, bd_next) { 1140 ++d->bd_rcount; 1141 slen = bpf_filter(d->bd_rfilter, pkt, pktlen, pktlen); 1142 if (slen != 0) { 1143 if (!gottime) { 1144 microtime(&tv); 1145 gottime = 1; 1146 } 1147 catchpacket(d, pkt, pktlen, slen, ovbcopy, &tv); 1148 } 1149 } 1150 1151 rel_mplock(); 1152 } 1153 1154 /* 1155 * Copy data from an mbuf chain into a buffer. This code is derived 1156 * from m_copydata in sys/uipc_mbuf.c. 1157 */ 1158 static void 1159 bpf_mcopy(const void *src_arg, void *dst_arg, size_t len) 1160 { 1161 const struct mbuf *m; 1162 u_int count; 1163 u_char *dst; 1164 1165 m = src_arg; 1166 dst = dst_arg; 1167 while (len > 0) { 1168 if (m == NULL) 1169 panic("bpf_mcopy"); 1170 count = min(m->m_len, len); 1171 bcopy(mtod(m, void *), dst, count); 1172 m = m->m_next; 1173 dst += count; 1174 len -= count; 1175 } 1176 } 1177 1178 /* 1179 * Process the packet in the mbuf chain m. The packet is parsed by each 1180 * listener's filter, and if accepted, stashed into the corresponding 1181 * buffer. 1182 */ 1183 void 1184 bpf_mtap(struct bpf_if *bp, struct mbuf *m) 1185 { 1186 struct bpf_d *d; 1187 u_int pktlen, slen; 1188 struct timeval tv; 1189 int gottime = 0; 1190 1191 get_mplock(); 1192 1193 /* Re-check */ 1194 if (bp == NULL) { 1195 rel_mplock(); 1196 return; 1197 } 1198 1199 /* Don't compute pktlen, if no descriptor is attached. */ 1200 if (SLIST_EMPTY(&bp->bif_dlist)) { 1201 rel_mplock(); 1202 return; 1203 } 1204 1205 pktlen = m_lengthm(m, NULL); 1206 1207 SLIST_FOREACH(d, &bp->bif_dlist, bd_next) { 1208 if (!d->bd_seesent && (m->m_pkthdr.rcvif == NULL)) 1209 continue; 1210 ++d->bd_rcount; 1211 slen = bpf_filter(d->bd_rfilter, (u_char *)m, pktlen, 0); 1212 if (slen != 0) { 1213 if (!gottime) { 1214 microtime(&tv); 1215 gottime = 1; 1216 } 1217 catchpacket(d, (u_char *)m, pktlen, slen, bpf_mcopy, 1218 &tv); 1219 } 1220 } 1221 1222 rel_mplock(); 1223 } 1224 1225 void 1226 bpf_mtap_family(struct bpf_if *bp, struct mbuf *m, sa_family_t family) 1227 { 1228 u_int family4; 1229 1230 KKASSERT(family != AF_UNSPEC); 1231 1232 family4 = (u_int)family; 1233 bpf_ptap(bp, m, &family4, sizeof(family4)); 1234 } 1235 1236 /* 1237 * Process the packet in the mbuf chain m with the header in m prepended. 1238 * The packet is parsed by each listener's filter, and if accepted, 1239 * stashed into the corresponding buffer. 1240 */ 1241 void 1242 bpf_ptap(struct bpf_if *bp, struct mbuf *m, const void *data, u_int dlen) 1243 { 1244 struct mbuf mb; 1245 1246 /* 1247 * Craft on-stack mbuf suitable for passing to bpf_mtap. 1248 * Note that we cut corners here; we only setup what's 1249 * absolutely needed--this mbuf should never go anywhere else. 1250 */ 1251 mb.m_next = m; 1252 mb.m_data = __DECONST(void *, data); /* LINTED */ 1253 mb.m_len = dlen; 1254 mb.m_pkthdr.rcvif = m->m_pkthdr.rcvif; 1255 1256 bpf_mtap(bp, &mb); 1257 } 1258 1259 /* 1260 * Move the packet data from interface memory (pkt) into the 1261 * store buffer. Return 1 if it's time to wakeup a listener (buffer full), 1262 * otherwise 0. "copy" is the routine called to do the actual data 1263 * transfer. bcopy is passed in to copy contiguous chunks, while 1264 * bpf_mcopy is passed in to copy mbuf chains. In the latter case, 1265 * pkt is really an mbuf. 1266 */ 1267 static void 1268 catchpacket(struct bpf_d *d, u_char *pkt, u_int pktlen, u_int snaplen, 1269 void (*cpfn)(const void *, void *, size_t), 1270 const struct timeval *tv) 1271 { 1272 struct bpf_hdr *hp; 1273 int totlen, curlen; 1274 int hdrlen = d->bd_bif->bif_hdrlen; 1275 /* 1276 * Figure out how many bytes to move. If the packet is 1277 * greater or equal to the snapshot length, transfer that 1278 * much. Otherwise, transfer the whole packet (unless 1279 * we hit the buffer size limit). 1280 */ 1281 totlen = hdrlen + min(snaplen, pktlen); 1282 if (totlen > d->bd_bufsize) 1283 totlen = d->bd_bufsize; 1284 1285 /* 1286 * Round up the end of the previous packet to the next longword. 1287 */ 1288 curlen = BPF_WORDALIGN(d->bd_slen); 1289 if (curlen + totlen > d->bd_bufsize) { 1290 /* 1291 * This packet will overflow the storage buffer. 1292 * Rotate the buffers if we can, then wakeup any 1293 * pending reads. 1294 */ 1295 if (d->bd_fbuf == NULL) { 1296 /* 1297 * We haven't completed the previous read yet, 1298 * so drop the packet. 1299 */ 1300 ++d->bd_dcount; 1301 return; 1302 } 1303 ROTATE_BUFFERS(d); 1304 bpf_wakeup(d); 1305 curlen = 0; 1306 } else if (d->bd_immediate || d->bd_state == BPF_TIMED_OUT) { 1307 /* 1308 * Immediate mode is set, or the read timeout has 1309 * already expired during a select call. A packet 1310 * arrived, so the reader should be woken up. 1311 */ 1312 bpf_wakeup(d); 1313 } 1314 1315 /* 1316 * Append the bpf header. 1317 */ 1318 hp = (struct bpf_hdr *)(d->bd_sbuf + curlen); 1319 hp->bh_tstamp = *tv; 1320 hp->bh_datalen = pktlen; 1321 hp->bh_hdrlen = hdrlen; 1322 /* 1323 * Copy the packet data into the store buffer and update its length. 1324 */ 1325 (*cpfn)(pkt, (u_char *)hp + hdrlen, (hp->bh_caplen = totlen - hdrlen)); 1326 d->bd_slen = curlen + totlen; 1327 } 1328 1329 /* 1330 * Initialize all nonzero fields of a descriptor. 1331 */ 1332 static int 1333 bpf_allocbufs(struct bpf_d *d) 1334 { 1335 d->bd_fbuf = kmalloc(d->bd_bufsize, M_BPF, M_WAITOK); 1336 d->bd_sbuf = kmalloc(d->bd_bufsize, M_BPF, M_WAITOK); 1337 d->bd_slen = 0; 1338 d->bd_hlen = 0; 1339 return(0); 1340 } 1341 1342 /* 1343 * Free buffers and packet filter program currently in use by a descriptor. 1344 * Called on close. 1345 */ 1346 static void 1347 bpf_freed(struct bpf_d *d) 1348 { 1349 /* 1350 * We don't need to lock out interrupts since this descriptor has 1351 * been detached from its interface and it yet hasn't been marked 1352 * free. 1353 */ 1354 if (d->bd_sbuf != NULL) { 1355 kfree(d->bd_sbuf, M_BPF); 1356 if (d->bd_hbuf != NULL) 1357 kfree(d->bd_hbuf, M_BPF); 1358 if (d->bd_fbuf != NULL) 1359 kfree(d->bd_fbuf, M_BPF); 1360 } 1361 if (d->bd_rfilter) 1362 kfree(d->bd_rfilter, M_BPF); 1363 if (d->bd_wfilter) 1364 kfree(d->bd_wfilter, M_BPF); 1365 } 1366 1367 /* 1368 * Attach an interface to bpf. ifp is a pointer to the structure 1369 * defining the interface to be attached, dlt is the link layer type, 1370 * and hdrlen is the fixed size of the link header (variable length 1371 * headers are not yet supported). 1372 */ 1373 void 1374 bpfattach(struct ifnet *ifp, u_int dlt, u_int hdrlen) 1375 { 1376 bpfattach_dlt(ifp, dlt, hdrlen, &ifp->if_bpf); 1377 } 1378 1379 void 1380 bpfattach_dlt(struct ifnet *ifp, u_int dlt, u_int hdrlen, struct bpf_if **driverp) 1381 { 1382 struct bpf_if *bp; 1383 1384 bp = kmalloc(sizeof *bp, M_BPF, M_WAITOK | M_ZERO); 1385 1386 SLIST_INIT(&bp->bif_dlist); 1387 bp->bif_ifp = ifp; 1388 bp->bif_dlt = dlt; 1389 bp->bif_driverp = driverp; 1390 *bp->bif_driverp = NULL; 1391 1392 bp->bif_next = bpf_iflist; 1393 bpf_iflist = bp; 1394 1395 /* 1396 * Compute the length of the bpf header. This is not necessarily 1397 * equal to SIZEOF_BPF_HDR because we want to insert spacing such 1398 * that the network layer header begins on a longword boundary (for 1399 * performance reasons and to alleviate alignment restrictions). 1400 */ 1401 bp->bif_hdrlen = BPF_WORDALIGN(hdrlen + SIZEOF_BPF_HDR) - hdrlen; 1402 1403 if (bootverbose) 1404 if_printf(ifp, "bpf attached\n"); 1405 } 1406 1407 /* 1408 * Detach bpf from an interface. This involves detaching each descriptor 1409 * associated with the interface, and leaving bd_bif NULL. Notify each 1410 * descriptor as it's detached so that any sleepers wake up and get 1411 * ENXIO. 1412 */ 1413 void 1414 bpfdetach(struct ifnet *ifp) 1415 { 1416 struct bpf_if *bp, *bp_prev; 1417 struct bpf_d *d; 1418 1419 crit_enter(); 1420 1421 /* Locate BPF interface information */ 1422 bp_prev = NULL; 1423 for (bp = bpf_iflist; bp != NULL; bp = bp->bif_next) { 1424 if (ifp == bp->bif_ifp) 1425 break; 1426 bp_prev = bp; 1427 } 1428 1429 /* Interface wasn't attached */ 1430 if (bp->bif_ifp == NULL) { 1431 crit_exit(); 1432 kprintf("bpfdetach: %s was not attached\n", ifp->if_xname); 1433 return; 1434 } 1435 1436 while ((d = SLIST_FIRST(&bp->bif_dlist)) != NULL) { 1437 bpf_detachd(d); 1438 bpf_wakeup(d); 1439 } 1440 1441 if (bp_prev != NULL) 1442 bp_prev->bif_next = bp->bif_next; 1443 else 1444 bpf_iflist = bp->bif_next; 1445 1446 kfree(bp, M_BPF); 1447 1448 crit_exit(); 1449 } 1450 1451 /* 1452 * Get a list of available data link type of the interface. 1453 */ 1454 static int 1455 bpf_getdltlist(struct bpf_d *d, struct bpf_dltlist *bfl) 1456 { 1457 int n, error; 1458 struct ifnet *ifp; 1459 struct bpf_if *bp; 1460 1461 ifp = d->bd_bif->bif_ifp; 1462 n = 0; 1463 error = 0; 1464 for (bp = bpf_iflist; bp != NULL; bp = bp->bif_next) { 1465 if (bp->bif_ifp != ifp) 1466 continue; 1467 if (bfl->bfl_list != NULL) { 1468 if (n >= bfl->bfl_len) { 1469 return (ENOMEM); 1470 } 1471 error = copyout(&bp->bif_dlt, 1472 bfl->bfl_list + n, sizeof(u_int)); 1473 } 1474 n++; 1475 } 1476 bfl->bfl_len = n; 1477 return(error); 1478 } 1479 1480 /* 1481 * Set the data link type of a BPF instance. 1482 */ 1483 static int 1484 bpf_setdlt(struct bpf_d *d, u_int dlt) 1485 { 1486 int error, opromisc; 1487 struct ifnet *ifp; 1488 struct bpf_if *bp; 1489 1490 if (d->bd_bif->bif_dlt == dlt) 1491 return (0); 1492 ifp = d->bd_bif->bif_ifp; 1493 for (bp = bpf_iflist; bp != NULL; bp = bp->bif_next) { 1494 if (bp->bif_ifp == ifp && bp->bif_dlt == dlt) 1495 break; 1496 } 1497 if (bp != NULL) { 1498 opromisc = d->bd_promisc; 1499 crit_enter(); 1500 bpf_detachd(d); 1501 bpf_attachd(d, bp); 1502 bpf_resetd(d); 1503 if (opromisc) { 1504 error = ifpromisc(bp->bif_ifp, 1); 1505 if (error) { 1506 if_printf(bp->bif_ifp, 1507 "bpf_setdlt: ifpromisc failed (%d)\n", 1508 error); 1509 } else { 1510 d->bd_promisc = 1; 1511 } 1512 } 1513 crit_exit(); 1514 } 1515 return(bp == NULL ? EINVAL : 0); 1516 } 1517 1518 static void 1519 bpf_drvinit(void *unused) 1520 { 1521 int i; 1522 1523 make_autoclone_dev(&bpf_ops, &DEVFS_CLONE_BITMAP(bpf), 1524 bpfclone, 0, 0, 0600, "bpf"); 1525 for (i = 0; i < BPF_PREALLOCATED_UNITS; i++) { 1526 make_dev(&bpf_ops, i, 0, 0, 0600, "bpf%d", i); 1527 devfs_clone_bitmap_set(&DEVFS_CLONE_BITMAP(bpf), i); 1528 } 1529 } 1530 1531 static void 1532 bpf_drvuninit(void *unused) 1533 { 1534 devfs_clone_handler_del("bpf"); 1535 dev_ops_remove_all(&bpf_ops); 1536 devfs_clone_bitmap_uninit(&DEVFS_CLONE_BITMAP(bpf)); 1537 } 1538 1539 SYSINIT(bpfdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,bpf_drvinit,NULL) 1540 SYSUNINIT(bpfdev, SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,bpf_drvuninit, NULL); 1541 1542 #else /* !BPF */ 1543 /* 1544 * NOP stubs to allow bpf-using drivers to load and function. 1545 * 1546 * A 'better' implementation would allow the core bpf functionality 1547 * to be loaded at runtime. 1548 */ 1549 1550 void 1551 bpf_tap(struct bpf_if *bp, u_char *pkt, u_int pktlen) 1552 { 1553 } 1554 1555 void 1556 bpf_mtap(struct bpf_if *bp, struct mbuf *m) 1557 { 1558 } 1559 1560 void 1561 bpf_ptap(struct bpf_if *bp, struct mbuf *m, const void *data, u_int dlen) 1562 { 1563 } 1564 1565 void 1566 bpfattach(struct ifnet *ifp, u_int dlt, u_int hdrlen) 1567 { 1568 } 1569 1570 void 1571 bpfattach_dlt(struct ifnet *ifp, u_int dlt, u_int hdrlen, struct bpf_if **driverp) 1572 { 1573 } 1574 1575 void 1576 bpfdetach(struct ifnet *ifp) 1577 { 1578 } 1579 1580 u_int 1581 bpf_filter(const struct bpf_insn *pc, u_char *p, u_int wirelen, u_int buflen) 1582 { 1583 return -1; /* "no filter" behaviour */ 1584 } 1585 1586 #endif /* !BPF */ 1587