1/*- 2 * Copyright (c) 1990, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from the Stanford/CMU enet packet filter, 6 * (net/enet.c) distributed as part of 4.3BSD, and code contributed 7 * to Berkeley by Steven McCanne and Van Jacobson both of Lawrence 8 * Berkeley Laboratory. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)bpf.c 8.4 (Berkeley) 1/9/95 35 */ 36 37#include <sys/cdefs.h> 38__FBSDID("$FreeBSD$"); 39 40#include "opt_bpf.h" 41#include "opt_compat.h" 42#include "opt_netgraph.h" 43 44#include <sys/types.h> 45#include <sys/param.h> 46#include <sys/lock.h> 47#include <sys/rwlock.h> 48#include <sys/systm.h> 49#include <sys/conf.h> 50#include <sys/fcntl.h> 51#include <sys/jail.h> 52#include <sys/malloc.h> 53#include <sys/mbuf.h> 54#include <sys/time.h> 55#include <sys/priv.h> 56#include <sys/proc.h> 57#include <sys/signalvar.h> 58#include <sys/filio.h> 59#include <sys/sockio.h> 60#include <sys/ttycom.h> 61#include <sys/uio.h> 62 63#include <sys/event.h> 64#include <sys/file.h> 65#include <sys/poll.h> 66#include <sys/proc.h> 67 68#include <sys/socket.h> 69 70#include <net/if.h> 71#define BPF_INTERNAL 72#include <net/bpf.h> 73#include <net/bpf_buffer.h> 74#ifdef BPF_JITTER 75#include <net/bpf_jitter.h> 76#endif 77#include <net/bpf_zerocopy.h> 78#include <net/bpfdesc.h> 79#include <net/vnet.h> 80 81#include <netinet/in.h> 82#include <netinet/if_ether.h> 83#include <sys/kernel.h> 84#include <sys/sysctl.h> 85 86#include <net80211/ieee80211_freebsd.h> 87 88#include <security/mac/mac_framework.h> 89 90MALLOC_DEFINE(M_BPF, "BPF", "BPF data"); 91 92#if defined(DEV_BPF) || defined(NETGRAPH_BPF) 93 94#define PRINET 26 /* interruptible */ 95 96#define SIZEOF_BPF_HDR(type) \ 97 (offsetof(type, bh_hdrlen) + sizeof(((type *)0)->bh_hdrlen)) 98 99#ifdef COMPAT_FREEBSD32 100#include <sys/mount.h> 101#include <compat/freebsd32/freebsd32.h> 102#define BPF_ALIGNMENT32 sizeof(int32_t) 103#define BPF_WORDALIGN32(x) (((x)+(BPF_ALIGNMENT32-1))&~(BPF_ALIGNMENT32-1)) 104 105#ifndef BURN_BRIDGES 106/* 107 * 32-bit version of structure prepended to each packet. We use this header 108 * instead of the standard one for 32-bit streams. We mark the a stream as 109 * 32-bit the first time we see a 32-bit compat ioctl request. 110 */ 111struct bpf_hdr32 { 112 struct timeval32 bh_tstamp; /* time stamp */ 113 uint32_t bh_caplen; /* length of captured portion */ 114 uint32_t bh_datalen; /* original length of packet */ 115 uint16_t bh_hdrlen; /* length of bpf header (this struct 116 plus alignment padding) */ 117}; 118#endif 119 120struct bpf_program32 { 121 u_int bf_len; 122 uint32_t bf_insns; 123}; 124 125struct bpf_dltlist32 { 126 u_int bfl_len; 127 u_int bfl_list; 128}; 129 130#define BIOCSETF32 _IOW('B', 103, struct bpf_program32) 131#define BIOCSRTIMEOUT32 _IOW('B', 109, struct timeval32) 132#define BIOCGRTIMEOUT32 _IOR('B', 110, struct timeval32) 133#define BIOCGDLTLIST32 _IOWR('B', 121, struct bpf_dltlist32) 134#define BIOCSETWF32 _IOW('B', 123, struct bpf_program32) 135#define BIOCSETFNR32 _IOW('B', 130, struct bpf_program32) 136#endif 137 138/* 139 * bpf_iflist is a list of BPF interface structures, each corresponding to a 140 * specific DLT. The same network interface might have several BPF interface 141 * structures registered by different layers in the stack (i.e., 802.11 142 * frames, ethernet frames, etc). 143 */ 144static LIST_HEAD(, bpf_if) bpf_iflist, bpf_freelist; 145static struct mtx bpf_mtx; /* bpf global lock */ 146static int bpf_bpfd_cnt; 147 148static void bpf_attachd(struct bpf_d *, struct bpf_if *); 149static void bpf_detachd(struct bpf_d *); 150static void bpf_detachd_locked(struct bpf_d *); 151static void bpf_freed(struct bpf_d *); 152static int bpf_movein(struct uio *, int, struct ifnet *, struct mbuf **, 153 struct sockaddr *, int *, struct bpf_insn *); 154static int bpf_setif(struct bpf_d *, struct ifreq *); 155static void bpf_timed_out(void *); 156static __inline void 157 bpf_wakeup(struct bpf_d *); 158static void catchpacket(struct bpf_d *, u_char *, u_int, u_int, 159 void (*)(struct bpf_d *, caddr_t, u_int, void *, u_int), 160 struct bintime *); 161static void reset_d(struct bpf_d *); 162static int bpf_setf(struct bpf_d *, struct bpf_program *, u_long cmd); 163static int bpf_getdltlist(struct bpf_d *, struct bpf_dltlist *); 164static int bpf_setdlt(struct bpf_d *, u_int); 165static void filt_bpfdetach(struct knote *); 166static int filt_bpfread(struct knote *, long); 167static void bpf_drvinit(void *); 168static int bpf_stats_sysctl(SYSCTL_HANDLER_ARGS); 169 170SYSCTL_NODE(_net, OID_AUTO, bpf, CTLFLAG_RW, 0, "bpf sysctl"); 171int bpf_maxinsns = BPF_MAXINSNS; 172SYSCTL_INT(_net_bpf, OID_AUTO, maxinsns, CTLFLAG_RW, 173 &bpf_maxinsns, 0, "Maximum bpf program instructions"); 174static int bpf_zerocopy_enable = 0; 175SYSCTL_INT(_net_bpf, OID_AUTO, zerocopy_enable, CTLFLAG_RW, 176 &bpf_zerocopy_enable, 0, "Enable new zero-copy BPF buffer sessions"); 177static SYSCTL_NODE(_net_bpf, OID_AUTO, stats, CTLFLAG_MPSAFE | CTLFLAG_RW, 178 bpf_stats_sysctl, "bpf statistics portal"); 179 180static VNET_DEFINE(int, bpf_optimize_writers) = 0; 181#define V_bpf_optimize_writers VNET(bpf_optimize_writers) 182SYSCTL_VNET_INT(_net_bpf, OID_AUTO, optimize_writers, 183 CTLFLAG_RW, &VNET_NAME(bpf_optimize_writers), 0, 184 "Do not send packets until BPF program is set"); 185 186static d_open_t bpfopen; 187static d_read_t bpfread; 188static d_write_t bpfwrite; 189static d_ioctl_t bpfioctl; 190static d_poll_t bpfpoll; 191static d_kqfilter_t bpfkqfilter; 192 193static struct cdevsw bpf_cdevsw = { 194 .d_version = D_VERSION, 195 .d_open = bpfopen, 196 .d_read = bpfread, 197 .d_write = bpfwrite, 198 .d_ioctl = bpfioctl, 199 .d_poll = bpfpoll, 200 .d_name = "bpf", 201 .d_kqfilter = bpfkqfilter, 202}; 203 204static struct filterops bpfread_filtops = { 205 .f_isfd = 1, 206 .f_detach = filt_bpfdetach, 207 .f_event = filt_bpfread, 208}; 209 210eventhandler_tag bpf_ifdetach_cookie = NULL; 211 212/* 213 * LOCKING MODEL USED BY BPF: 214 * Locks: 215 * 1) global lock (BPF_LOCK). Mutex, used to protect interface addition/removal, 216 * some global counters and every bpf_if reference. 217 * 2) Interface lock. Rwlock, used to protect list of BPF descriptors and their filters. 218 * 3) Descriptor lock. Mutex, used to protect BPF buffers and various structure fields 219 * used by bpf_mtap code. 220 * 221 * Lock order: 222 * 223 * Global lock, interface lock, descriptor lock 224 * 225 * We have to acquire interface lock before descriptor main lock due to BPF_MTAP[2] 226 * working model. In many places (like bpf_detachd) we start with BPF descriptor 227 * (and we need to at least rlock it to get reliable interface pointer). This 228 * gives us potential LOR. As a result, we use global lock to protect from bpf_if 229 * change in every such place. 230 * 231 * Changing d->bd_bif is protected by 1) global lock, 2) interface lock and 232 * 3) descriptor main wlock. 233 * Reading bd_bif can be protected by any of these locks, typically global lock. 234 * 235 * Changing read/write BPF filter is protected by the same three locks, 236 * the same applies for reading. 237 * 238 * Sleeping in global lock is not allowed due to bpfdetach() using it. 239 */ 240 241/* 242 * Wrapper functions for various buffering methods. If the set of buffer 243 * modes expands, we will probably want to introduce a switch data structure 244 * similar to protosw, et. 245 */ 246static void 247bpf_append_bytes(struct bpf_d *d, caddr_t buf, u_int offset, void *src, 248 u_int len) 249{ 250 251 BPFD_LOCK_ASSERT(d); 252 253 switch (d->bd_bufmode) { 254 case BPF_BUFMODE_BUFFER: 255 return (bpf_buffer_append_bytes(d, buf, offset, src, len)); 256 257 case BPF_BUFMODE_ZBUF: 258 d->bd_zcopy++; 259 return (bpf_zerocopy_append_bytes(d, buf, offset, src, len)); 260 261 default: 262 panic("bpf_buf_append_bytes"); 263 } 264} 265 266static void 267bpf_append_mbuf(struct bpf_d *d, caddr_t buf, u_int offset, void *src, 268 u_int len) 269{ 270 271 BPFD_LOCK_ASSERT(d); 272 273 switch (d->bd_bufmode) { 274 case BPF_BUFMODE_BUFFER: 275 return (bpf_buffer_append_mbuf(d, buf, offset, src, len)); 276 277 case BPF_BUFMODE_ZBUF: 278 d->bd_zcopy++; 279 return (bpf_zerocopy_append_mbuf(d, buf, offset, src, len)); 280 281 default: 282 panic("bpf_buf_append_mbuf"); 283 } 284} 285 286/* 287 * This function gets called when the free buffer is re-assigned. 288 */ 289static void 290bpf_buf_reclaimed(struct bpf_d *d) 291{ 292 293 BPFD_LOCK_ASSERT(d); 294 295 switch (d->bd_bufmode) { 296 case BPF_BUFMODE_BUFFER: 297 return; 298 299 case BPF_BUFMODE_ZBUF: 300 bpf_zerocopy_buf_reclaimed(d); 301 return; 302 303 default: 304 panic("bpf_buf_reclaimed"); 305 } 306} 307 308/* 309 * If the buffer mechanism has a way to decide that a held buffer can be made 310 * free, then it is exposed via the bpf_canfreebuf() interface. (1) is 311 * returned if the buffer can be discarded, (0) is returned if it cannot. 312 */ 313static int 314bpf_canfreebuf(struct bpf_d *d) 315{ 316 317 BPFD_LOCK_ASSERT(d); 318 319 switch (d->bd_bufmode) { 320 case BPF_BUFMODE_ZBUF: 321 return (bpf_zerocopy_canfreebuf(d)); 322 } 323 return (0); 324} 325 326/* 327 * Allow the buffer model to indicate that the current store buffer is 328 * immutable, regardless of the appearance of space. Return (1) if the 329 * buffer is writable, and (0) if not. 330 */ 331static int 332bpf_canwritebuf(struct bpf_d *d) 333{ 334 BPFD_LOCK_ASSERT(d); 335 336 switch (d->bd_bufmode) { 337 case BPF_BUFMODE_ZBUF: 338 return (bpf_zerocopy_canwritebuf(d)); 339 } 340 return (1); 341} 342 343/* 344 * Notify buffer model that an attempt to write to the store buffer has 345 * resulted in a dropped packet, in which case the buffer may be considered 346 * full. 347 */ 348static void 349bpf_buffull(struct bpf_d *d) 350{ 351 352 BPFD_LOCK_ASSERT(d); 353 354 switch (d->bd_bufmode) { 355 case BPF_BUFMODE_ZBUF: 356 bpf_zerocopy_buffull(d); 357 break; 358 } 359} 360 361/* 362 * Notify the buffer model that a buffer has moved into the hold position. 363 */ 364void 365bpf_bufheld(struct bpf_d *d) 366{ 367 368 BPFD_LOCK_ASSERT(d); 369 370 switch (d->bd_bufmode) { 371 case BPF_BUFMODE_ZBUF: 372 bpf_zerocopy_bufheld(d); 373 break; 374 } 375} 376 377static void 378bpf_free(struct bpf_d *d) 379{ 380 381 switch (d->bd_bufmode) { 382 case BPF_BUFMODE_BUFFER: 383 return (bpf_buffer_free(d)); 384 385 case BPF_BUFMODE_ZBUF: 386 return (bpf_zerocopy_free(d)); 387 388 default: 389 panic("bpf_buf_free"); 390 } 391} 392 393static int 394bpf_uiomove(struct bpf_d *d, caddr_t buf, u_int len, struct uio *uio) 395{ 396 397 if (d->bd_bufmode != BPF_BUFMODE_BUFFER) 398 return (EOPNOTSUPP); 399 return (bpf_buffer_uiomove(d, buf, len, uio)); 400} 401 402static int 403bpf_ioctl_sblen(struct bpf_d *d, u_int *i) 404{ 405 406 if (d->bd_bufmode != BPF_BUFMODE_BUFFER) 407 return (EOPNOTSUPP); 408 return (bpf_buffer_ioctl_sblen(d, i)); 409} 410 411static int 412bpf_ioctl_getzmax(struct thread *td, struct bpf_d *d, size_t *i) 413{ 414 415 if (d->bd_bufmode != BPF_BUFMODE_ZBUF) 416 return (EOPNOTSUPP); 417 return (bpf_zerocopy_ioctl_getzmax(td, d, i)); 418} 419 420static int 421bpf_ioctl_rotzbuf(struct thread *td, struct bpf_d *d, struct bpf_zbuf *bz) 422{ 423 424 if (d->bd_bufmode != BPF_BUFMODE_ZBUF) 425 return (EOPNOTSUPP); 426 return (bpf_zerocopy_ioctl_rotzbuf(td, d, bz)); 427} 428 429static int 430bpf_ioctl_setzbuf(struct thread *td, struct bpf_d *d, struct bpf_zbuf *bz) 431{ 432 433 if (d->bd_bufmode != BPF_BUFMODE_ZBUF) 434 return (EOPNOTSUPP); 435 return (bpf_zerocopy_ioctl_setzbuf(td, d, bz)); 436} 437 438/* 439 * General BPF functions. 440 */ 441static int 442bpf_movein(struct uio *uio, int linktype, struct ifnet *ifp, struct mbuf **mp, 443 struct sockaddr *sockp, int *hdrlen, struct bpf_insn *wfilter) 444{ 445 const struct ieee80211_bpf_params *p; 446 struct ether_header *eh; 447 struct mbuf *m; 448 int error; 449 int len; 450 int hlen; 451 int slen; 452 453 /* 454 * Build a sockaddr based on the data link layer type. 455 * We do this at this level because the ethernet header 456 * is copied directly into the data field of the sockaddr. 457 * In the case of SLIP, there is no header and the packet 458 * is forwarded as is. 459 * Also, we are careful to leave room at the front of the mbuf 460 * for the link level header. 461 */ 462 switch (linktype) { 463 464 case DLT_SLIP: 465 sockp->sa_family = AF_INET; 466 hlen = 0; 467 break; 468 469 case DLT_EN10MB: 470 sockp->sa_family = AF_UNSPEC; 471 /* XXX Would MAXLINKHDR be better? */ 472 hlen = ETHER_HDR_LEN; 473 break; 474 475 case DLT_FDDI: 476 sockp->sa_family = AF_IMPLINK; 477 hlen = 0; 478 break; 479 480 case DLT_RAW: 481 sockp->sa_family = AF_UNSPEC; 482 hlen = 0; 483 break; 484 485 case DLT_NULL: 486 /* 487 * null interface types require a 4 byte pseudo header which 488 * corresponds to the address family of the packet. 489 */ 490 sockp->sa_family = AF_UNSPEC; 491 hlen = 4; 492 break; 493 494 case DLT_ATM_RFC1483: 495 /* 496 * en atm driver requires 4-byte atm pseudo header. 497 * though it isn't standard, vpi:vci needs to be 498 * specified anyway. 499 */ 500 sockp->sa_family = AF_UNSPEC; 501 hlen = 12; /* XXX 4(ATM_PH) + 3(LLC) + 5(SNAP) */ 502 break; 503 504 case DLT_PPP: 505 sockp->sa_family = AF_UNSPEC; 506 hlen = 4; /* This should match PPP_HDRLEN */ 507 break; 508 509 case DLT_IEEE802_11: /* IEEE 802.11 wireless */ 510 sockp->sa_family = AF_IEEE80211; 511 hlen = 0; 512 break; 513 514 case DLT_IEEE802_11_RADIO: /* IEEE 802.11 wireless w/ phy params */ 515 sockp->sa_family = AF_IEEE80211; 516 sockp->sa_len = 12; /* XXX != 0 */ 517 hlen = sizeof(struct ieee80211_bpf_params); 518 break; 519 520 default: 521 return (EIO); 522 } 523 524 len = uio->uio_resid; 525 if (len < hlen || len - hlen > ifp->if_mtu) 526 return (EMSGSIZE); 527 528 m = m_get2(len, M_WAITOK, MT_DATA, M_PKTHDR); 529 if (m == NULL) 530 return (EIO); 531 m->m_pkthdr.len = m->m_len = len; 532 *mp = m; 533 534 error = uiomove(mtod(m, u_char *), len, uio); 535 if (error) 536 goto bad; 537 538 slen = bpf_filter(wfilter, mtod(m, u_char *), len, len); 539 if (slen == 0) { 540 error = EPERM; 541 goto bad; 542 } 543 544 /* Check for multicast destination */ 545 switch (linktype) { 546 case DLT_EN10MB: 547 eh = mtod(m, struct ether_header *); 548 if (ETHER_IS_MULTICAST(eh->ether_dhost)) { 549 if (bcmp(ifp->if_broadcastaddr, eh->ether_dhost, 550 ETHER_ADDR_LEN) == 0) 551 m->m_flags |= M_BCAST; 552 else 553 m->m_flags |= M_MCAST; 554 } 555 break; 556 } 557 558 /* 559 * Make room for link header, and copy it to sockaddr 560 */ 561 if (hlen != 0) { 562 if (sockp->sa_family == AF_IEEE80211) { 563 /* 564 * Collect true length from the parameter header 565 * NB: sockp is known to be zero'd so if we do a 566 * short copy unspecified parameters will be 567 * zero. 568 * NB: packet may not be aligned after stripping 569 * bpf params 570 * XXX check ibp_vers 571 */ 572 p = mtod(m, const struct ieee80211_bpf_params *); 573 hlen = p->ibp_len; 574 if (hlen > sizeof(sockp->sa_data)) { 575 error = EINVAL; 576 goto bad; 577 } 578 } 579 bcopy(m->m_data, sockp->sa_data, hlen); 580 } 581 *hdrlen = hlen; 582 583 return (0); 584bad: 585 m_freem(m); 586 return (error); 587} 588 589/* 590 * Attach file to the bpf interface, i.e. make d listen on bp. 591 */ 592static void 593bpf_attachd(struct bpf_d *d, struct bpf_if *bp) 594{ 595 int op_w; 596 597 BPF_LOCK_ASSERT(); 598 599 /* 600 * Save sysctl value to protect from sysctl change 601 * between reads 602 */ 603 op_w = V_bpf_optimize_writers; 604 605 if (d->bd_bif != NULL) 606 bpf_detachd_locked(d); 607 /* 608 * Point d at bp, and add d to the interface's list. 609 * Since there are many applicaiotns using BPF for 610 * sending raw packets only (dhcpd, cdpd are good examples) 611 * we can delay adding d to the list of active listeners until 612 * some filter is configured. 613 */ 614 615 BPFIF_WLOCK(bp); 616 BPFD_LOCK(d); 617 618 d->bd_bif = bp; 619 620 if (op_w != 0) { 621 /* Add to writers-only list */ 622 LIST_INSERT_HEAD(&bp->bif_wlist, d, bd_next); 623 /* 624 * We decrement bd_writer on every filter set operation. 625 * First BIOCSETF is done by pcap_open_live() to set up 626 * snap length. After that appliation usually sets its own filter 627 */ 628 d->bd_writer = 2; 629 } else 630 LIST_INSERT_HEAD(&bp->bif_dlist, d, bd_next); 631 632 BPFD_UNLOCK(d); 633 BPFIF_WUNLOCK(bp); 634 635 bpf_bpfd_cnt++; 636 637 CTR3(KTR_NET, "%s: bpf_attach called by pid %d, adding to %s list", 638 __func__, d->bd_pid, d->bd_writer ? "writer" : "active"); 639 640 if (op_w == 0) 641 EVENTHANDLER_INVOKE(bpf_track, bp->bif_ifp, bp->bif_dlt, 1); 642} 643 644/* 645 * Add d to the list of active bp filters. 646 * Reuqires bpf_attachd() to be called before 647 */ 648static void 649bpf_upgraded(struct bpf_d *d) 650{ 651 struct bpf_if *bp; 652 653 BPF_LOCK_ASSERT(); 654 655 bp = d->bd_bif; 656 657 /* 658 * Filter can be set several times without specifying interface. 659 * Mark d as reader and exit. 660 */ 661 if (bp == NULL) { 662 BPFD_LOCK(d); 663 d->bd_writer = 0; 664 BPFD_UNLOCK(d); 665 return; 666 } 667 668 BPFIF_WLOCK(bp); 669 BPFD_LOCK(d); 670 671 /* Remove from writers-only list */ 672 LIST_REMOVE(d, bd_next); 673 LIST_INSERT_HEAD(&bp->bif_dlist, d, bd_next); 674 /* Mark d as reader */ 675 d->bd_writer = 0; 676 677 BPFD_UNLOCK(d); 678 BPFIF_WUNLOCK(bp); 679 680 CTR2(KTR_NET, "%s: upgrade required by pid %d", __func__, d->bd_pid); 681 682 EVENTHANDLER_INVOKE(bpf_track, bp->bif_ifp, bp->bif_dlt, 1); 683} 684 685/* 686 * Detach a file from its interface. 687 */ 688static void 689bpf_detachd(struct bpf_d *d) 690{ 691 BPF_LOCK(); 692 bpf_detachd_locked(d); 693 BPF_UNLOCK(); 694} 695 696static void 697bpf_detachd_locked(struct bpf_d *d) 698{ 699 int error; 700 struct bpf_if *bp; 701 struct ifnet *ifp; 702 703 CTR2(KTR_NET, "%s: detach required by pid %d", __func__, d->bd_pid); 704 705 BPF_LOCK_ASSERT(); 706 707 /* Check if descriptor is attached */ 708 if ((bp = d->bd_bif) == NULL) 709 return; 710 711 BPFIF_WLOCK(bp); 712 BPFD_LOCK(d); 713 714 /* Save bd_writer value */ 715 error = d->bd_writer; 716 717 /* 718 * Remove d from the interface's descriptor list. 719 */ 720 LIST_REMOVE(d, bd_next); 721 722 ifp = bp->bif_ifp; 723 d->bd_bif = NULL; 724 BPFD_UNLOCK(d); 725 BPFIF_WUNLOCK(bp); 726 727 bpf_bpfd_cnt--; 728 729 /* Call event handler iff d is attached */ 730 if (error == 0) 731 EVENTHANDLER_INVOKE(bpf_track, ifp, bp->bif_dlt, 0); 732 733 /* 734 * Check if this descriptor had requested promiscuous mode. 735 * If so, turn it off. 736 */ 737 if (d->bd_promisc) { 738 d->bd_promisc = 0; 739 CURVNET_SET(ifp->if_vnet); 740 error = ifpromisc(ifp, 0); 741 CURVNET_RESTORE(); 742 if (error != 0 && error != ENXIO) { 743 /* 744 * ENXIO can happen if a pccard is unplugged 745 * Something is really wrong if we were able to put 746 * the driver into promiscuous mode, but can't 747 * take it out. 748 */ 749 if_printf(bp->bif_ifp, 750 "bpf_detach: ifpromisc failed (%d)\n", error); 751 } 752 } 753} 754 755/* 756 * Close the descriptor by detaching it from its interface, 757 * deallocating its buffers, and marking it free. 758 */ 759static void 760bpf_dtor(void *data) 761{ 762 struct bpf_d *d = data; 763 764 BPFD_LOCK(d); 765 if (d->bd_state == BPF_WAITING) 766 callout_stop(&d->bd_callout); 767 d->bd_state = BPF_IDLE; 768 BPFD_UNLOCK(d); 769 funsetown(&d->bd_sigio); 770 bpf_detachd(d); 771#ifdef MAC 772 mac_bpfdesc_destroy(d); 773#endif /* MAC */ 774 seldrain(&d->bd_sel); 775 knlist_destroy(&d->bd_sel.si_note); 776 callout_drain(&d->bd_callout); 777 bpf_freed(d); 778 free(d, M_BPF); 779} 780 781/* 782 * Open ethernet device. Returns ENXIO for illegal minor device number, 783 * EBUSY if file is open by another process. 784 */ 785/* ARGSUSED */ 786static int 787bpfopen(struct cdev *dev, int flags, int fmt, struct thread *td) 788{ 789 struct bpf_d *d; 790 int error, size; 791 792 d = malloc(sizeof(*d), M_BPF, M_WAITOK | M_ZERO); 793 error = devfs_set_cdevpriv(d, bpf_dtor); 794 if (error != 0) { 795 free(d, M_BPF); 796 return (error); 797 } 798 799 /* 800 * For historical reasons, perform a one-time initialization call to 801 * the buffer routines, even though we're not yet committed to a 802 * particular buffer method. 803 */ 804 bpf_buffer_init(d); 805 d->bd_hbuf_in_use = 0; 806 d->bd_bufmode = BPF_BUFMODE_BUFFER; 807 d->bd_sig = SIGIO; 808 d->bd_direction = BPF_D_INOUT; 809 BPF_PID_REFRESH(d, td); 810#ifdef MAC 811 mac_bpfdesc_init(d); 812 mac_bpfdesc_create(td->td_ucred, d); 813#endif 814 mtx_init(&d->bd_lock, devtoname(dev), "bpf cdev lock", MTX_DEF); 815 callout_init_mtx(&d->bd_callout, &d->bd_lock, 0); 816 knlist_init_mtx(&d->bd_sel.si_note, &d->bd_lock); 817 818 /* Allocate default buffers */ 819 size = d->bd_bufsize; 820 bpf_buffer_ioctl_sblen(d, &size); 821 822 return (0); 823} 824 825/* 826 * bpfread - read next chunk of packets from buffers 827 */ 828static int 829bpfread(struct cdev *dev, struct uio *uio, int ioflag) 830{ 831 struct bpf_d *d; 832 int error; 833 int non_block; 834 int timed_out; 835 836 error = devfs_get_cdevpriv((void **)&d); 837 if (error != 0) 838 return (error); 839 840 /* 841 * Restrict application to use a buffer the same size as 842 * as kernel buffers. 843 */ 844 if (uio->uio_resid != d->bd_bufsize) 845 return (EINVAL); 846 847 non_block = ((ioflag & O_NONBLOCK) != 0); 848 849 BPFD_LOCK(d); 850 BPF_PID_REFRESH_CUR(d); 851 if (d->bd_bufmode != BPF_BUFMODE_BUFFER) { 852 BPFD_UNLOCK(d); 853 return (EOPNOTSUPP); 854 } 855 if (d->bd_state == BPF_WAITING) 856 callout_stop(&d->bd_callout); 857 timed_out = (d->bd_state == BPF_TIMED_OUT); 858 d->bd_state = BPF_IDLE; 859 while (d->bd_hbuf_in_use) { 860 error = mtx_sleep(&d->bd_hbuf_in_use, &d->bd_lock, 861 PRINET|PCATCH, "bd_hbuf", 0); 862 if (error != 0) { 863 BPFD_UNLOCK(d); 864 return (error); 865 } 866 } 867 /* 868 * If the hold buffer is empty, then do a timed sleep, which 869 * ends when the timeout expires or when enough packets 870 * have arrived to fill the store buffer. 871 */ 872 while (d->bd_hbuf == NULL) { 873 if (d->bd_slen != 0) { 874 /* 875 * A packet(s) either arrived since the previous 876 * read or arrived while we were asleep. 877 */ 878 if (d->bd_immediate || non_block || timed_out) { 879 /* 880 * Rotate the buffers and return what's here 881 * if we are in immediate mode, non-blocking 882 * flag is set, or this descriptor timed out. 883 */ 884 ROTATE_BUFFERS(d); 885 break; 886 } 887 } 888 889 /* 890 * No data is available, check to see if the bpf device 891 * is still pointed at a real interface. If not, return 892 * ENXIO so that the userland process knows to rebind 893 * it before using it again. 894 */ 895 if (d->bd_bif == NULL) { 896 BPFD_UNLOCK(d); 897 return (ENXIO); 898 } 899 900 if (non_block) { 901 BPFD_UNLOCK(d); 902 return (EWOULDBLOCK); 903 } 904 error = msleep(d, &d->bd_lock, PRINET|PCATCH, 905 "bpf", d->bd_rtout); 906 if (error == EINTR || error == ERESTART) { 907 BPFD_UNLOCK(d); 908 return (error); 909 } 910 if (error == EWOULDBLOCK) { 911 /* 912 * On a timeout, return what's in the buffer, 913 * which may be nothing. If there is something 914 * in the store buffer, we can rotate the buffers. 915 */ 916 if (d->bd_hbuf) 917 /* 918 * We filled up the buffer in between 919 * getting the timeout and arriving 920 * here, so we don't need to rotate. 921 */ 922 break; 923 924 if (d->bd_slen == 0) { 925 BPFD_UNLOCK(d); 926 return (0); 927 } 928 ROTATE_BUFFERS(d); 929 break; 930 } 931 } 932 /* 933 * At this point, we know we have something in the hold slot. 934 */ 935 d->bd_hbuf_in_use = 1; 936 BPFD_UNLOCK(d); 937 938 /* 939 * Move data from hold buffer into user space. 940 * We know the entire buffer is transferred since 941 * we checked above that the read buffer is bpf_bufsize bytes. 942 * 943 * We do not have to worry about simultaneous reads because 944 * we waited for sole access to the hold buffer above. 945 */ 946 error = bpf_uiomove(d, d->bd_hbuf, d->bd_hlen, uio); 947 948 BPFD_LOCK(d); 949 KASSERT(d->bd_hbuf != NULL, ("bpfread: lost bd_hbuf")); 950 d->bd_fbuf = d->bd_hbuf; 951 d->bd_hbuf = NULL; 952 d->bd_hlen = 0; 953 bpf_buf_reclaimed(d); 954 d->bd_hbuf_in_use = 0; 955 wakeup(&d->bd_hbuf_in_use); 956 BPFD_UNLOCK(d); 957 958 return (error); 959} 960 961/* 962 * If there are processes sleeping on this descriptor, wake them up. 963 */ 964static __inline void 965bpf_wakeup(struct bpf_d *d) 966{ 967 968 BPFD_LOCK_ASSERT(d); 969 if (d->bd_state == BPF_WAITING) { 970 callout_stop(&d->bd_callout); 971 d->bd_state = BPF_IDLE; 972 } 973 wakeup(d); 974 if (d->bd_async && d->bd_sig && d->bd_sigio) 975 pgsigio(&d->bd_sigio, d->bd_sig, 0); 976 977 selwakeuppri(&d->bd_sel, PRINET); 978 KNOTE_LOCKED(&d->bd_sel.si_note, 0); 979} 980 981static void 982bpf_timed_out(void *arg) 983{ 984 struct bpf_d *d = (struct bpf_d *)arg; 985 986 BPFD_LOCK_ASSERT(d); 987 988 if (callout_pending(&d->bd_callout) || !callout_active(&d->bd_callout)) 989 return; 990 if (d->bd_state == BPF_WAITING) { 991 d->bd_state = BPF_TIMED_OUT; 992 if (d->bd_slen != 0) 993 bpf_wakeup(d); 994 } 995} 996 997static int 998bpf_ready(struct bpf_d *d) 999{ 1000 1001 BPFD_LOCK_ASSERT(d); 1002 1003 if (!bpf_canfreebuf(d) && d->bd_hlen != 0) 1004 return (1); 1005 if ((d->bd_immediate || d->bd_state == BPF_TIMED_OUT) && 1006 d->bd_slen != 0) 1007 return (1); 1008 return (0); 1009} 1010 1011static int 1012bpfwrite(struct cdev *dev, struct uio *uio, int ioflag) 1013{ 1014 struct bpf_d *d; 1015 struct ifnet *ifp; 1016 struct mbuf *m, *mc; 1017 struct sockaddr dst; 1018 int error, hlen; 1019 1020 error = devfs_get_cdevpriv((void **)&d); 1021 if (error != 0) 1022 return (error); 1023 1024 BPF_PID_REFRESH_CUR(d); 1025 d->bd_wcount++; 1026 /* XXX: locking required */ 1027 if (d->bd_bif == NULL) { 1028 d->bd_wdcount++; 1029 return (ENXIO); 1030 } 1031 1032 ifp = d->bd_bif->bif_ifp; 1033 1034 if ((ifp->if_flags & IFF_UP) == 0) { 1035 d->bd_wdcount++; 1036 return (ENETDOWN); 1037 } 1038 1039 if (uio->uio_resid == 0) { 1040 d->bd_wdcount++; 1041 return (0); 1042 } 1043 1044 bzero(&dst, sizeof(dst)); 1045 m = NULL; 1046 hlen = 0; 1047 /* XXX: bpf_movein() can sleep */ 1048 error = bpf_movein(uio, (int)d->bd_bif->bif_dlt, ifp, 1049 &m, &dst, &hlen, d->bd_wfilter); 1050 if (error) { 1051 d->bd_wdcount++; 1052 return (error); 1053 } 1054 d->bd_wfcount++; 1055 if (d->bd_hdrcmplt) 1056 dst.sa_family = pseudo_AF_HDRCMPLT; 1057 1058 if (d->bd_feedback) { 1059 mc = m_dup(m, M_NOWAIT); 1060 if (mc != NULL) 1061 mc->m_pkthdr.rcvif = ifp; 1062 /* Set M_PROMISC for outgoing packets to be discarded. */ 1063 if (d->bd_direction == BPF_D_INOUT) 1064 m->m_flags |= M_PROMISC; 1065 } else 1066 mc = NULL; 1067 1068 m->m_pkthdr.len -= hlen; 1069 m->m_len -= hlen; 1070 m->m_data += hlen; /* XXX */ 1071 1072 CURVNET_SET(ifp->if_vnet); 1073#ifdef MAC 1074 BPFD_LOCK(d); 1075 mac_bpfdesc_create_mbuf(d, m); 1076 if (mc != NULL) 1077 mac_bpfdesc_create_mbuf(d, mc); 1078 BPFD_UNLOCK(d); 1079#endif 1080 1081 error = (*ifp->if_output)(ifp, m, &dst, NULL); 1082 if (error) 1083 d->bd_wdcount++; 1084 1085 if (mc != NULL) { 1086 if (error == 0) 1087 (*ifp->if_input)(ifp, mc); 1088 else 1089 m_freem(mc); 1090 } 1091 CURVNET_RESTORE(); 1092 1093 return (error); 1094} 1095 1096/* 1097 * Reset a descriptor by flushing its packet buffer and clearing the receive 1098 * and drop counts. This is doable for kernel-only buffers, but with 1099 * zero-copy buffers, we can't write to (or rotate) buffers that are 1100 * currently owned by userspace. It would be nice if we could encapsulate 1101 * this logic in the buffer code rather than here. 1102 */ 1103static void 1104reset_d(struct bpf_d *d) 1105{ 1106 1107 BPFD_LOCK_ASSERT(d); 1108 1109 while (d->bd_hbuf_in_use) 1110 mtx_sleep(&d->bd_hbuf_in_use, &d->bd_lock, PRINET, 1111 "bd_hbuf", 0); 1112 if ((d->bd_hbuf != NULL) && 1113 (d->bd_bufmode != BPF_BUFMODE_ZBUF || bpf_canfreebuf(d))) { 1114 /* Free the hold buffer. */ 1115 d->bd_fbuf = d->bd_hbuf; 1116 d->bd_hbuf = NULL; 1117 d->bd_hlen = 0; 1118 bpf_buf_reclaimed(d); 1119 } 1120 if (bpf_canwritebuf(d)) 1121 d->bd_slen = 0; 1122 d->bd_rcount = 0; 1123 d->bd_dcount = 0; 1124 d->bd_fcount = 0; 1125 d->bd_wcount = 0; 1126 d->bd_wfcount = 0; 1127 d->bd_wdcount = 0; 1128 d->bd_zcopy = 0; 1129} 1130 1131/* 1132 * FIONREAD Check for read packet available. 1133 * SIOCGIFADDR Get interface address - convenient hook to driver. 1134 * BIOCGBLEN Get buffer len [for read()]. 1135 * BIOCSETF Set read filter. 1136 * BIOCSETFNR Set read filter without resetting descriptor. 1137 * BIOCSETWF Set write filter. 1138 * BIOCFLUSH Flush read packet buffer. 1139 * BIOCPROMISC Put interface into promiscuous mode. 1140 * BIOCGDLT Get link layer type. 1141 * BIOCGETIF Get interface name. 1142 * BIOCSETIF Set interface. 1143 * BIOCSRTIMEOUT Set read timeout. 1144 * BIOCGRTIMEOUT Get read timeout. 1145 * BIOCGSTATS Get packet stats. 1146 * BIOCIMMEDIATE Set immediate mode. 1147 * BIOCVERSION Get filter language version. 1148 * BIOCGHDRCMPLT Get "header already complete" flag 1149 * BIOCSHDRCMPLT Set "header already complete" flag 1150 * BIOCGDIRECTION Get packet direction flag 1151 * BIOCSDIRECTION Set packet direction flag 1152 * BIOCGTSTAMP Get time stamp format and resolution. 1153 * BIOCSTSTAMP Set time stamp format and resolution. 1154 * BIOCLOCK Set "locked" flag 1155 * BIOCFEEDBACK Set packet feedback mode. 1156 * BIOCSETZBUF Set current zero-copy buffer locations. 1157 * BIOCGETZMAX Get maximum zero-copy buffer size. 1158 * BIOCROTZBUF Force rotation of zero-copy buffer 1159 * BIOCSETBUFMODE Set buffer mode. 1160 * BIOCGETBUFMODE Get current buffer mode. 1161 */ 1162/* ARGSUSED */ 1163static int 1164bpfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, 1165 struct thread *td) 1166{ 1167 struct bpf_d *d; 1168 int error; 1169 1170 error = devfs_get_cdevpriv((void **)&d); 1171 if (error != 0) 1172 return (error); 1173 1174 /* 1175 * Refresh PID associated with this descriptor. 1176 */ 1177 BPFD_LOCK(d); 1178 BPF_PID_REFRESH(d, td); 1179 if (d->bd_state == BPF_WAITING) 1180 callout_stop(&d->bd_callout); 1181 d->bd_state = BPF_IDLE; 1182 BPFD_UNLOCK(d); 1183 1184 if (d->bd_locked == 1) { 1185 switch (cmd) { 1186 case BIOCGBLEN: 1187 case BIOCFLUSH: 1188 case BIOCGDLT: 1189 case BIOCGDLTLIST: 1190#ifdef COMPAT_FREEBSD32 1191 case BIOCGDLTLIST32: 1192#endif 1193 case BIOCGETIF: 1194 case BIOCGRTIMEOUT: 1195#if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1196 case BIOCGRTIMEOUT32: 1197#endif 1198 case BIOCGSTATS: 1199 case BIOCVERSION: 1200 case BIOCGRSIG: 1201 case BIOCGHDRCMPLT: 1202 case BIOCSTSTAMP: 1203 case BIOCFEEDBACK: 1204 case FIONREAD: 1205 case BIOCLOCK: 1206 case BIOCSRTIMEOUT: 1207#if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1208 case BIOCSRTIMEOUT32: 1209#endif 1210 case BIOCIMMEDIATE: 1211 case TIOCGPGRP: 1212 case BIOCROTZBUF: 1213 break; 1214 default: 1215 return (EPERM); 1216 } 1217 } 1218#ifdef COMPAT_FREEBSD32 1219 /* 1220 * If we see a 32-bit compat ioctl, mark the stream as 32-bit so 1221 * that it will get 32-bit packet headers. 1222 */ 1223 switch (cmd) { 1224 case BIOCSETF32: 1225 case BIOCSETFNR32: 1226 case BIOCSETWF32: 1227 case BIOCGDLTLIST32: 1228 case BIOCGRTIMEOUT32: 1229 case BIOCSRTIMEOUT32: 1230 BPFD_LOCK(d); 1231 d->bd_compat32 = 1; 1232 BPFD_UNLOCK(d); 1233 } 1234#endif 1235 1236 CURVNET_SET(TD_TO_VNET(td)); 1237 switch (cmd) { 1238 1239 default: 1240 error = EINVAL; 1241 break; 1242 1243 /* 1244 * Check for read packet available. 1245 */ 1246 case FIONREAD: 1247 { 1248 int n; 1249 1250 BPFD_LOCK(d); 1251 n = d->bd_slen; 1252 while (d->bd_hbuf_in_use) 1253 mtx_sleep(&d->bd_hbuf_in_use, &d->bd_lock, 1254 PRINET, "bd_hbuf", 0); 1255 if (d->bd_hbuf) 1256 n += d->bd_hlen; 1257 BPFD_UNLOCK(d); 1258 1259 *(int *)addr = n; 1260 break; 1261 } 1262 1263 case SIOCGIFADDR: 1264 { 1265 struct ifnet *ifp; 1266 1267 if (d->bd_bif == NULL) 1268 error = EINVAL; 1269 else { 1270 ifp = d->bd_bif->bif_ifp; 1271 error = (*ifp->if_ioctl)(ifp, cmd, addr); 1272 } 1273 break; 1274 } 1275 1276 /* 1277 * Get buffer len [for read()]. 1278 */ 1279 case BIOCGBLEN: 1280 BPFD_LOCK(d); 1281 *(u_int *)addr = d->bd_bufsize; 1282 BPFD_UNLOCK(d); 1283 break; 1284 1285 /* 1286 * Set buffer length. 1287 */ 1288 case BIOCSBLEN: 1289 error = bpf_ioctl_sblen(d, (u_int *)addr); 1290 break; 1291 1292 /* 1293 * Set link layer read filter. 1294 */ 1295 case BIOCSETF: 1296 case BIOCSETFNR: 1297 case BIOCSETWF: 1298#ifdef COMPAT_FREEBSD32 1299 case BIOCSETF32: 1300 case BIOCSETFNR32: 1301 case BIOCSETWF32: 1302#endif 1303 error = bpf_setf(d, (struct bpf_program *)addr, cmd); 1304 break; 1305 1306 /* 1307 * Flush read packet buffer. 1308 */ 1309 case BIOCFLUSH: 1310 BPFD_LOCK(d); 1311 reset_d(d); 1312 BPFD_UNLOCK(d); 1313 break; 1314 1315 /* 1316 * Put interface into promiscuous mode. 1317 */ 1318 case BIOCPROMISC: 1319 if (d->bd_bif == NULL) { 1320 /* 1321 * No interface attached yet. 1322 */ 1323 error = EINVAL; 1324 break; 1325 } 1326 if (d->bd_promisc == 0) { 1327 error = ifpromisc(d->bd_bif->bif_ifp, 1); 1328 if (error == 0) 1329 d->bd_promisc = 1; 1330 } 1331 break; 1332 1333 /* 1334 * Get current data link type. 1335 */ 1336 case BIOCGDLT: 1337 BPF_LOCK(); 1338 if (d->bd_bif == NULL) 1339 error = EINVAL; 1340 else 1341 *(u_int *)addr = d->bd_bif->bif_dlt; 1342 BPF_UNLOCK(); 1343 break; 1344 1345 /* 1346 * Get a list of supported data link types. 1347 */ 1348#ifdef COMPAT_FREEBSD32 1349 case BIOCGDLTLIST32: 1350 { 1351 struct bpf_dltlist32 *list32; 1352 struct bpf_dltlist dltlist; 1353 1354 list32 = (struct bpf_dltlist32 *)addr; 1355 dltlist.bfl_len = list32->bfl_len; 1356 dltlist.bfl_list = PTRIN(list32->bfl_list); 1357 BPF_LOCK(); 1358 if (d->bd_bif == NULL) 1359 error = EINVAL; 1360 else { 1361 error = bpf_getdltlist(d, &dltlist); 1362 if (error == 0) 1363 list32->bfl_len = dltlist.bfl_len; 1364 } 1365 BPF_UNLOCK(); 1366 break; 1367 } 1368#endif 1369 1370 case BIOCGDLTLIST: 1371 BPF_LOCK(); 1372 if (d->bd_bif == NULL) 1373 error = EINVAL; 1374 else 1375 error = bpf_getdltlist(d, (struct bpf_dltlist *)addr); 1376 BPF_UNLOCK(); 1377 break; 1378 1379 /* 1380 * Set data link type. 1381 */ 1382 case BIOCSDLT: 1383 BPF_LOCK(); 1384 if (d->bd_bif == NULL) 1385 error = EINVAL; 1386 else 1387 error = bpf_setdlt(d, *(u_int *)addr); 1388 BPF_UNLOCK(); 1389 break; 1390 1391 /* 1392 * Get interface name. 1393 */ 1394 case BIOCGETIF: 1395 BPF_LOCK(); 1396 if (d->bd_bif == NULL) 1397 error = EINVAL; 1398 else { 1399 struct ifnet *const ifp = d->bd_bif->bif_ifp; 1400 struct ifreq *const ifr = (struct ifreq *)addr; 1401 1402 strlcpy(ifr->ifr_name, ifp->if_xname, 1403 sizeof(ifr->ifr_name)); 1404 } 1405 BPF_UNLOCK(); 1406 break; 1407 1408 /* 1409 * Set interface. 1410 */ 1411 case BIOCSETIF: 1412 BPF_LOCK(); 1413 error = bpf_setif(d, (struct ifreq *)addr); 1414 BPF_UNLOCK(); 1415 break; 1416 1417 /* 1418 * Set read timeout. 1419 */ 1420 case BIOCSRTIMEOUT: 1421#if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1422 case BIOCSRTIMEOUT32: 1423#endif 1424 { 1425 struct timeval *tv = (struct timeval *)addr; 1426#if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1427 struct timeval32 *tv32; 1428 struct timeval tv64; 1429 1430 if (cmd == BIOCSRTIMEOUT32) { 1431 tv32 = (struct timeval32 *)addr; 1432 tv = &tv64; 1433 tv->tv_sec = tv32->tv_sec; 1434 tv->tv_usec = tv32->tv_usec; 1435 } else 1436#endif 1437 tv = (struct timeval *)addr; 1438 1439 /* 1440 * Subtract 1 tick from tvtohz() since this isn't 1441 * a one-shot timer. 1442 */ 1443 if ((error = itimerfix(tv)) == 0) 1444 d->bd_rtout = tvtohz(tv) - 1; 1445 break; 1446 } 1447 1448 /* 1449 * Get read timeout. 1450 */ 1451 case BIOCGRTIMEOUT: 1452#if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1453 case BIOCGRTIMEOUT32: 1454#endif 1455 { 1456 struct timeval *tv; 1457#if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1458 struct timeval32 *tv32; 1459 struct timeval tv64; 1460 1461 if (cmd == BIOCGRTIMEOUT32) 1462 tv = &tv64; 1463 else 1464#endif 1465 tv = (struct timeval *)addr; 1466 1467 tv->tv_sec = d->bd_rtout / hz; 1468 tv->tv_usec = (d->bd_rtout % hz) * tick; 1469#if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1470 if (cmd == BIOCGRTIMEOUT32) { 1471 tv32 = (struct timeval32 *)addr; 1472 tv32->tv_sec = tv->tv_sec; 1473 tv32->tv_usec = tv->tv_usec; 1474 } 1475#endif 1476 1477 break; 1478 } 1479 1480 /* 1481 * Get packet stats. 1482 */ 1483 case BIOCGSTATS: 1484 { 1485 struct bpf_stat *bs = (struct bpf_stat *)addr; 1486 1487 /* XXXCSJP overflow */ 1488 bs->bs_recv = d->bd_rcount; 1489 bs->bs_drop = d->bd_dcount; 1490 break; 1491 } 1492 1493 /* 1494 * Set immediate mode. 1495 */ 1496 case BIOCIMMEDIATE: 1497 BPFD_LOCK(d); 1498 d->bd_immediate = *(u_int *)addr; 1499 BPFD_UNLOCK(d); 1500 break; 1501 1502 case BIOCVERSION: 1503 { 1504 struct bpf_version *bv = (struct bpf_version *)addr; 1505 1506 bv->bv_major = BPF_MAJOR_VERSION; 1507 bv->bv_minor = BPF_MINOR_VERSION; 1508 break; 1509 } 1510 1511 /* 1512 * Get "header already complete" flag 1513 */ 1514 case BIOCGHDRCMPLT: 1515 BPFD_LOCK(d); 1516 *(u_int *)addr = d->bd_hdrcmplt; 1517 BPFD_UNLOCK(d); 1518 break; 1519 1520 /* 1521 * Set "header already complete" flag 1522 */ 1523 case BIOCSHDRCMPLT: 1524 BPFD_LOCK(d); 1525 d->bd_hdrcmplt = *(u_int *)addr ? 1 : 0; 1526 BPFD_UNLOCK(d); 1527 break; 1528 1529 /* 1530 * Get packet direction flag 1531 */ 1532 case BIOCGDIRECTION: 1533 BPFD_LOCK(d); 1534 *(u_int *)addr = d->bd_direction; 1535 BPFD_UNLOCK(d); 1536 break; 1537 1538 /* 1539 * Set packet direction flag 1540 */ 1541 case BIOCSDIRECTION: 1542 { 1543 u_int direction; 1544 1545 direction = *(u_int *)addr; 1546 switch (direction) { 1547 case BPF_D_IN: 1548 case BPF_D_INOUT: 1549 case BPF_D_OUT: 1550 BPFD_LOCK(d); 1551 d->bd_direction = direction; 1552 BPFD_UNLOCK(d); 1553 break; 1554 default: 1555 error = EINVAL; 1556 } 1557 } 1558 break; 1559 1560 /* 1561 * Get packet timestamp format and resolution. 1562 */ 1563 case BIOCGTSTAMP: 1564 BPFD_LOCK(d); 1565 *(u_int *)addr = d->bd_tstamp; 1566 BPFD_UNLOCK(d); 1567 break; 1568 1569 /* 1570 * Set packet timestamp format and resolution. 1571 */ 1572 case BIOCSTSTAMP: 1573 { 1574 u_int func; 1575 1576 func = *(u_int *)addr; 1577 if (BPF_T_VALID(func)) 1578 d->bd_tstamp = func; 1579 else 1580 error = EINVAL; 1581 } 1582 break; 1583 1584 case BIOCFEEDBACK: 1585 BPFD_LOCK(d); 1586 d->bd_feedback = *(u_int *)addr; 1587 BPFD_UNLOCK(d); 1588 break; 1589 1590 case BIOCLOCK: 1591 BPFD_LOCK(d); 1592 d->bd_locked = 1; 1593 BPFD_UNLOCK(d); 1594 break; 1595 1596 case FIONBIO: /* Non-blocking I/O */ 1597 break; 1598 1599 case FIOASYNC: /* Send signal on receive packets */ 1600 BPFD_LOCK(d); 1601 d->bd_async = *(int *)addr; 1602 BPFD_UNLOCK(d); 1603 break; 1604 1605 case FIOSETOWN: 1606 /* 1607 * XXX: Add some sort of locking here? 1608 * fsetown() can sleep. 1609 */ 1610 error = fsetown(*(int *)addr, &d->bd_sigio); 1611 break; 1612 1613 case FIOGETOWN: 1614 BPFD_LOCK(d); 1615 *(int *)addr = fgetown(&d->bd_sigio); 1616 BPFD_UNLOCK(d); 1617 break; 1618 1619 /* This is deprecated, FIOSETOWN should be used instead. */ 1620 case TIOCSPGRP: 1621 error = fsetown(-(*(int *)addr), &d->bd_sigio); 1622 break; 1623 1624 /* This is deprecated, FIOGETOWN should be used instead. */ 1625 case TIOCGPGRP: 1626 *(int *)addr = -fgetown(&d->bd_sigio); 1627 break; 1628 1629 case BIOCSRSIG: /* Set receive signal */ 1630 { 1631 u_int sig; 1632 1633 sig = *(u_int *)addr; 1634 1635 if (sig >= NSIG) 1636 error = EINVAL; 1637 else { 1638 BPFD_LOCK(d); 1639 d->bd_sig = sig; 1640 BPFD_UNLOCK(d); 1641 } 1642 break; 1643 } 1644 case BIOCGRSIG: 1645 BPFD_LOCK(d); 1646 *(u_int *)addr = d->bd_sig; 1647 BPFD_UNLOCK(d); 1648 break; 1649 1650 case BIOCGETBUFMODE: 1651 BPFD_LOCK(d); 1652 *(u_int *)addr = d->bd_bufmode; 1653 BPFD_UNLOCK(d); 1654 break; 1655 1656 case BIOCSETBUFMODE: 1657 /* 1658 * Allow the buffering mode to be changed as long as we 1659 * haven't yet committed to a particular mode. Our 1660 * definition of commitment, for now, is whether or not a 1661 * buffer has been allocated or an interface attached, since 1662 * that's the point where things get tricky. 1663 */ 1664 switch (*(u_int *)addr) { 1665 case BPF_BUFMODE_BUFFER: 1666 break; 1667 1668 case BPF_BUFMODE_ZBUF: 1669 if (bpf_zerocopy_enable) 1670 break; 1671 /* FALLSTHROUGH */ 1672 1673 default: 1674 CURVNET_RESTORE(); 1675 return (EINVAL); 1676 } 1677 1678 BPFD_LOCK(d); 1679 if (d->bd_sbuf != NULL || d->bd_hbuf != NULL || 1680 d->bd_fbuf != NULL || d->bd_bif != NULL) { 1681 BPFD_UNLOCK(d); 1682 CURVNET_RESTORE(); 1683 return (EBUSY); 1684 } 1685 d->bd_bufmode = *(u_int *)addr; 1686 BPFD_UNLOCK(d); 1687 break; 1688 1689 case BIOCGETZMAX: 1690 error = bpf_ioctl_getzmax(td, d, (size_t *)addr); 1691 break; 1692 1693 case BIOCSETZBUF: 1694 error = bpf_ioctl_setzbuf(td, d, (struct bpf_zbuf *)addr); 1695 break; 1696 1697 case BIOCROTZBUF: 1698 error = bpf_ioctl_rotzbuf(td, d, (struct bpf_zbuf *)addr); 1699 break; 1700 } 1701 CURVNET_RESTORE(); 1702 return (error); 1703} 1704 1705/* 1706 * Set d's packet filter program to fp. If this file already has a filter, 1707 * free it and replace it. Returns EINVAL for bogus requests. 1708 * 1709 * Note we need global lock here to serialize bpf_setf() and bpf_setif() calls 1710 * since reading d->bd_bif can't be protected by d or interface lock due to 1711 * lock order. 1712 * 1713 * Additionally, we have to acquire interface write lock due to bpf_mtap() uses 1714 * interface read lock to read all filers. 1715 * 1716 */ 1717static int 1718bpf_setf(struct bpf_d *d, struct bpf_program *fp, u_long cmd) 1719{ 1720#ifdef COMPAT_FREEBSD32 1721 struct bpf_program fp_swab; 1722 struct bpf_program32 *fp32; 1723#endif 1724 struct bpf_insn *fcode, *old; 1725#ifdef BPF_JITTER 1726 bpf_jit_filter *jfunc, *ofunc; 1727#endif 1728 size_t size; 1729 u_int flen; 1730 int need_upgrade; 1731 1732#ifdef COMPAT_FREEBSD32 1733 switch (cmd) { 1734 case BIOCSETF32: 1735 case BIOCSETWF32: 1736 case BIOCSETFNR32: 1737 fp32 = (struct bpf_program32 *)fp; 1738 fp_swab.bf_len = fp32->bf_len; 1739 fp_swab.bf_insns = (struct bpf_insn *)(uintptr_t)fp32->bf_insns; 1740 fp = &fp_swab; 1741 switch (cmd) { 1742 case BIOCSETF32: 1743 cmd = BIOCSETF; 1744 break; 1745 case BIOCSETWF32: 1746 cmd = BIOCSETWF; 1747 break; 1748 } 1749 break; 1750 } 1751#endif 1752 1753 fcode = NULL; 1754#ifdef BPF_JITTER 1755 jfunc = ofunc = NULL; 1756#endif 1757 need_upgrade = 0; 1758 1759 /* 1760 * Check new filter validness before acquiring any locks. 1761 * Allocate memory for new filter, if needed. 1762 */ 1763 flen = fp->bf_len; 1764 if (flen > bpf_maxinsns || (fp->bf_insns == NULL && flen != 0)) 1765 return (EINVAL); 1766 size = flen * sizeof(*fp->bf_insns); 1767 if (size > 0) { 1768 /* We're setting up new filter. Copy and check actual data. */ 1769 fcode = malloc(size, M_BPF, M_WAITOK); 1770 if (copyin(fp->bf_insns, fcode, size) != 0 || 1771 !bpf_validate(fcode, flen)) { 1772 free(fcode, M_BPF); 1773 return (EINVAL); 1774 } 1775#ifdef BPF_JITTER 1776 /* Filter is copied inside fcode and is perfectly valid. */ 1777 jfunc = bpf_jitter(fcode, flen); 1778#endif 1779 } 1780 1781 BPF_LOCK(); 1782 1783 /* 1784 * Set up new filter. 1785 * Protect filter change by interface lock. 1786 * Additionally, we are protected by global lock here. 1787 */ 1788 if (d->bd_bif != NULL) 1789 BPFIF_WLOCK(d->bd_bif); 1790 BPFD_LOCK(d); 1791 if (cmd == BIOCSETWF) { 1792 old = d->bd_wfilter; 1793 d->bd_wfilter = fcode; 1794 } else { 1795 old = d->bd_rfilter; 1796 d->bd_rfilter = fcode; 1797#ifdef BPF_JITTER 1798 ofunc = d->bd_bfilter; 1799 d->bd_bfilter = jfunc; 1800#endif 1801 if (cmd == BIOCSETF) 1802 reset_d(d); 1803 1804 if (fcode != NULL) { 1805 /* 1806 * Do not require upgrade by first BIOCSETF 1807 * (used to set snaplen) by pcap_open_live(). 1808 */ 1809 if (d->bd_writer != 0 && --d->bd_writer == 0) 1810 need_upgrade = 1; 1811 CTR4(KTR_NET, "%s: filter function set by pid %d, " 1812 "bd_writer counter %d, need_upgrade %d", 1813 __func__, d->bd_pid, d->bd_writer, need_upgrade); 1814 } 1815 } 1816 BPFD_UNLOCK(d); 1817 if (d->bd_bif != NULL) 1818 BPFIF_WUNLOCK(d->bd_bif); 1819 if (old != NULL) 1820 free(old, M_BPF); 1821#ifdef BPF_JITTER 1822 if (ofunc != NULL) 1823 bpf_destroy_jit_filter(ofunc); 1824#endif 1825 1826 /* Move d to active readers list. */ 1827 if (need_upgrade) 1828 bpf_upgraded(d); 1829 1830 BPF_UNLOCK(); 1831 return (0); 1832} 1833 1834/* 1835 * Detach a file from its current interface (if attached at all) and attach 1836 * to the interface indicated by the name stored in ifr. 1837 * Return an errno or 0. 1838 */ 1839static int 1840bpf_setif(struct bpf_d *d, struct ifreq *ifr) 1841{ 1842 struct bpf_if *bp; 1843 struct ifnet *theywant; 1844 1845 BPF_LOCK_ASSERT(); 1846 1847 theywant = ifunit(ifr->ifr_name); 1848 if (theywant == NULL || theywant->if_bpf == NULL) 1849 return (ENXIO); 1850 1851 bp = theywant->if_bpf; 1852 1853 /* Check if interface is not being detached from BPF */ 1854 BPFIF_RLOCK(bp); 1855 if (bp->flags & BPFIF_FLAG_DYING) { 1856 BPFIF_RUNLOCK(bp); 1857 return (ENXIO); 1858 } 1859 BPFIF_RUNLOCK(bp); 1860 1861 /* 1862 * Behavior here depends on the buffering model. If we're using 1863 * kernel memory buffers, then we can allocate them here. If we're 1864 * using zero-copy, then the user process must have registered 1865 * buffers by the time we get here. If not, return an error. 1866 */ 1867 switch (d->bd_bufmode) { 1868 case BPF_BUFMODE_BUFFER: 1869 case BPF_BUFMODE_ZBUF: 1870 if (d->bd_sbuf == NULL) 1871 return (EINVAL); 1872 break; 1873 1874 default: 1875 panic("bpf_setif: bufmode %d", d->bd_bufmode); 1876 } 1877 if (bp != d->bd_bif) 1878 bpf_attachd(d, bp); 1879 BPFD_LOCK(d); 1880 reset_d(d); 1881 BPFD_UNLOCK(d); 1882 return (0); 1883} 1884 1885/* 1886 * Support for select() and poll() system calls 1887 * 1888 * Return true iff the specific operation will not block indefinitely. 1889 * Otherwise, return false but make a note that a selwakeup() must be done. 1890 */ 1891static int 1892bpfpoll(struct cdev *dev, int events, struct thread *td) 1893{ 1894 struct bpf_d *d; 1895 int revents; 1896 1897 if (devfs_get_cdevpriv((void **)&d) != 0 || d->bd_bif == NULL) 1898 return (events & 1899 (POLLHUP|POLLIN|POLLRDNORM|POLLOUT|POLLWRNORM)); 1900 1901 /* 1902 * Refresh PID associated with this descriptor. 1903 */ 1904 revents = events & (POLLOUT | POLLWRNORM); 1905 BPFD_LOCK(d); 1906 BPF_PID_REFRESH(d, td); 1907 if (events & (POLLIN | POLLRDNORM)) { 1908 if (bpf_ready(d)) 1909 revents |= events & (POLLIN | POLLRDNORM); 1910 else { 1911 selrecord(td, &d->bd_sel); 1912 /* Start the read timeout if necessary. */ 1913 if (d->bd_rtout > 0 && d->bd_state == BPF_IDLE) { 1914 callout_reset(&d->bd_callout, d->bd_rtout, 1915 bpf_timed_out, d); 1916 d->bd_state = BPF_WAITING; 1917 } 1918 } 1919 } 1920 BPFD_UNLOCK(d); 1921 return (revents); 1922} 1923 1924/* 1925 * Support for kevent() system call. Register EVFILT_READ filters and 1926 * reject all others. 1927 */ 1928int 1929bpfkqfilter(struct cdev *dev, struct knote *kn) 1930{ 1931 struct bpf_d *d; 1932 1933 if (devfs_get_cdevpriv((void **)&d) != 0 || 1934 kn->kn_filter != EVFILT_READ) 1935 return (1); 1936 1937 /* 1938 * Refresh PID associated with this descriptor. 1939 */ 1940 BPFD_LOCK(d); 1941 BPF_PID_REFRESH_CUR(d); 1942 kn->kn_fop = &bpfread_filtops; 1943 kn->kn_hook = d; 1944 knlist_add(&d->bd_sel.si_note, kn, 1); 1945 BPFD_UNLOCK(d); 1946 1947 return (0); 1948} 1949 1950static void 1951filt_bpfdetach(struct knote *kn) 1952{ 1953 struct bpf_d *d = (struct bpf_d *)kn->kn_hook; 1954 1955 knlist_remove(&d->bd_sel.si_note, kn, 0); 1956} 1957 1958static int 1959filt_bpfread(struct knote *kn, long hint) 1960{ 1961 struct bpf_d *d = (struct bpf_d *)kn->kn_hook; 1962 int ready; 1963 1964 BPFD_LOCK_ASSERT(d); 1965 ready = bpf_ready(d); 1966 if (ready) { 1967 kn->kn_data = d->bd_slen; 1968 while (d->bd_hbuf_in_use) 1969 mtx_sleep(&d->bd_hbuf_in_use, &d->bd_lock, 1970 PRINET, "bd_hbuf", 0); 1971 if (d->bd_hbuf) 1972 kn->kn_data += d->bd_hlen; 1973 } else if (d->bd_rtout > 0 && d->bd_state == BPF_IDLE) { 1974 callout_reset(&d->bd_callout, d->bd_rtout, 1975 bpf_timed_out, d); 1976 d->bd_state = BPF_WAITING; 1977 } 1978 1979 return (ready); 1980} 1981 1982#define BPF_TSTAMP_NONE 0 1983#define BPF_TSTAMP_FAST 1 1984#define BPF_TSTAMP_NORMAL 2 1985#define BPF_TSTAMP_EXTERN 3 1986 1987static int 1988bpf_ts_quality(int tstype) 1989{ 1990 1991 if (tstype == BPF_T_NONE) 1992 return (BPF_TSTAMP_NONE); 1993 if ((tstype & BPF_T_FAST) != 0) 1994 return (BPF_TSTAMP_FAST); 1995 1996 return (BPF_TSTAMP_NORMAL); 1997} 1998 1999static int 2000bpf_gettime(struct bintime *bt, int tstype, struct mbuf *m) 2001{ 2002 struct m_tag *tag; 2003 int quality; 2004 2005 quality = bpf_ts_quality(tstype); 2006 if (quality == BPF_TSTAMP_NONE) 2007 return (quality); 2008 2009 if (m != NULL) { 2010 tag = m_tag_locate(m, MTAG_BPF, MTAG_BPF_TIMESTAMP, NULL); 2011 if (tag != NULL) { 2012 *bt = *(struct bintime *)(tag + 1); 2013 return (BPF_TSTAMP_EXTERN); 2014 } 2015 } 2016 if (quality == BPF_TSTAMP_NORMAL) 2017 binuptime(bt); 2018 else 2019 getbinuptime(bt); 2020 2021 return (quality); 2022} 2023 2024/* 2025 * Incoming linkage from device drivers. Process the packet pkt, of length 2026 * pktlen, which is stored in a contiguous buffer. The packet is parsed 2027 * by each process' filter, and if accepted, stashed into the corresponding 2028 * buffer. 2029 */ 2030void 2031bpf_tap(struct bpf_if *bp, u_char *pkt, u_int pktlen) 2032{ 2033 struct bintime bt; 2034 struct bpf_d *d; 2035#ifdef BPF_JITTER 2036 bpf_jit_filter *bf; 2037#endif 2038 u_int slen; 2039 int gottime; 2040 2041 gottime = BPF_TSTAMP_NONE; 2042 2043 BPFIF_RLOCK(bp); 2044 2045 LIST_FOREACH(d, &bp->bif_dlist, bd_next) { 2046 /* 2047 * We are not using any locks for d here because: 2048 * 1) any filter change is protected by interface 2049 * write lock 2050 * 2) destroying/detaching d is protected by interface 2051 * write lock, too 2052 */ 2053 2054 /* XXX: Do not protect counter for the sake of performance. */ 2055 ++d->bd_rcount; 2056 /* 2057 * NB: We dont call BPF_CHECK_DIRECTION() here since there is no 2058 * way for the caller to indiciate to us whether this packet 2059 * is inbound or outbound. In the bpf_mtap() routines, we use 2060 * the interface pointers on the mbuf to figure it out. 2061 */ 2062#ifdef BPF_JITTER 2063 bf = bpf_jitter_enable != 0 ? d->bd_bfilter : NULL; 2064 if (bf != NULL) 2065 slen = (*(bf->func))(pkt, pktlen, pktlen); 2066 else 2067#endif 2068 slen = bpf_filter(d->bd_rfilter, pkt, pktlen, pktlen); 2069 if (slen != 0) { 2070 /* 2071 * Filter matches. Let's to acquire write lock. 2072 */ 2073 BPFD_LOCK(d); 2074 2075 d->bd_fcount++; 2076 if (gottime < bpf_ts_quality(d->bd_tstamp)) 2077 gottime = bpf_gettime(&bt, d->bd_tstamp, NULL); 2078#ifdef MAC 2079 if (mac_bpfdesc_check_receive(d, bp->bif_ifp) == 0) 2080#endif 2081 catchpacket(d, pkt, pktlen, slen, 2082 bpf_append_bytes, &bt); 2083 BPFD_UNLOCK(d); 2084 } 2085 } 2086 BPFIF_RUNLOCK(bp); 2087} 2088 2089#define BPF_CHECK_DIRECTION(d, r, i) \ 2090 (((d)->bd_direction == BPF_D_IN && (r) != (i)) || \ 2091 ((d)->bd_direction == BPF_D_OUT && (r) == (i))) 2092 2093/* 2094 * Incoming linkage from device drivers, when packet is in an mbuf chain. 2095 * Locking model is explained in bpf_tap(). 2096 */ 2097void 2098bpf_mtap(struct bpf_if *bp, struct mbuf *m) 2099{ 2100 struct bintime bt; 2101 struct bpf_d *d; 2102#ifdef BPF_JITTER 2103 bpf_jit_filter *bf; 2104#endif 2105 u_int pktlen, slen; 2106 int gottime; 2107 2108 /* Skip outgoing duplicate packets. */ 2109 if ((m->m_flags & M_PROMISC) != 0 && m->m_pkthdr.rcvif == NULL) { 2110 m->m_flags &= ~M_PROMISC; 2111 return; 2112 } 2113 2114 pktlen = m_length(m, NULL); 2115 gottime = BPF_TSTAMP_NONE; 2116 2117 BPFIF_RLOCK(bp); 2118 2119 LIST_FOREACH(d, &bp->bif_dlist, bd_next) { 2120 if (BPF_CHECK_DIRECTION(d, m->m_pkthdr.rcvif, bp->bif_ifp)) 2121 continue; 2122 ++d->bd_rcount; 2123#ifdef BPF_JITTER 2124 bf = bpf_jitter_enable != 0 ? d->bd_bfilter : NULL; 2125 /* XXX We cannot handle multiple mbufs. */ 2126 if (bf != NULL && m->m_next == NULL) 2127 slen = (*(bf->func))(mtod(m, u_char *), pktlen, pktlen); 2128 else 2129#endif 2130 slen = bpf_filter(d->bd_rfilter, (u_char *)m, pktlen, 0); 2131 if (slen != 0) { 2132 BPFD_LOCK(d); 2133 2134 d->bd_fcount++; 2135 if (gottime < bpf_ts_quality(d->bd_tstamp)) 2136 gottime = bpf_gettime(&bt, d->bd_tstamp, m); 2137#ifdef MAC 2138 if (mac_bpfdesc_check_receive(d, bp->bif_ifp) == 0) 2139#endif 2140 catchpacket(d, (u_char *)m, pktlen, slen, 2141 bpf_append_mbuf, &bt); 2142 BPFD_UNLOCK(d); 2143 } 2144 } 2145 BPFIF_RUNLOCK(bp); 2146} 2147 2148/* 2149 * Incoming linkage from device drivers, when packet is in 2150 * an mbuf chain and to be prepended by a contiguous header. 2151 */ 2152void 2153bpf_mtap2(struct bpf_if *bp, void *data, u_int dlen, struct mbuf *m) 2154{ 2155 struct bintime bt; 2156 struct mbuf mb; 2157 struct bpf_d *d; 2158 u_int pktlen, slen; 2159 int gottime; 2160 2161 /* Skip outgoing duplicate packets. */ 2162 if ((m->m_flags & M_PROMISC) != 0 && m->m_pkthdr.rcvif == NULL) { 2163 m->m_flags &= ~M_PROMISC; 2164 return; 2165 } 2166 2167 pktlen = m_length(m, NULL); 2168 /* 2169 * Craft on-stack mbuf suitable for passing to bpf_filter. 2170 * Note that we cut corners here; we only setup what's 2171 * absolutely needed--this mbuf should never go anywhere else. 2172 */ 2173 mb.m_next = m; 2174 mb.m_data = data; 2175 mb.m_len = dlen; 2176 pktlen += dlen; 2177 2178 gottime = BPF_TSTAMP_NONE; 2179 2180 BPFIF_RLOCK(bp); 2181 2182 LIST_FOREACH(d, &bp->bif_dlist, bd_next) { 2183 if (BPF_CHECK_DIRECTION(d, m->m_pkthdr.rcvif, bp->bif_ifp)) 2184 continue; 2185 ++d->bd_rcount; 2186 slen = bpf_filter(d->bd_rfilter, (u_char *)&mb, pktlen, 0); 2187 if (slen != 0) { 2188 BPFD_LOCK(d); 2189 2190 d->bd_fcount++; 2191 if (gottime < bpf_ts_quality(d->bd_tstamp)) 2192 gottime = bpf_gettime(&bt, d->bd_tstamp, m); 2193#ifdef MAC 2194 if (mac_bpfdesc_check_receive(d, bp->bif_ifp) == 0) 2195#endif 2196 catchpacket(d, (u_char *)&mb, pktlen, slen, 2197 bpf_append_mbuf, &bt); 2198 BPFD_UNLOCK(d); 2199 } 2200 } 2201 BPFIF_RUNLOCK(bp); 2202} 2203 2204#undef BPF_CHECK_DIRECTION 2205 2206#undef BPF_TSTAMP_NONE 2207#undef BPF_TSTAMP_FAST 2208#undef BPF_TSTAMP_NORMAL 2209#undef BPF_TSTAMP_EXTERN 2210 2211static int 2212bpf_hdrlen(struct bpf_d *d) 2213{ 2214 int hdrlen; 2215 2216 hdrlen = d->bd_bif->bif_hdrlen; 2217#ifndef BURN_BRIDGES 2218 if (d->bd_tstamp == BPF_T_NONE || 2219 BPF_T_FORMAT(d->bd_tstamp) == BPF_T_MICROTIME) 2220#ifdef COMPAT_FREEBSD32 2221 if (d->bd_compat32) 2222 hdrlen += SIZEOF_BPF_HDR(struct bpf_hdr32); 2223 else 2224#endif 2225 hdrlen += SIZEOF_BPF_HDR(struct bpf_hdr); 2226 else 2227#endif 2228 hdrlen += SIZEOF_BPF_HDR(struct bpf_xhdr); 2229#ifdef COMPAT_FREEBSD32 2230 if (d->bd_compat32) 2231 hdrlen = BPF_WORDALIGN32(hdrlen); 2232 else 2233#endif 2234 hdrlen = BPF_WORDALIGN(hdrlen); 2235 2236 return (hdrlen - d->bd_bif->bif_hdrlen); 2237} 2238 2239static void 2240bpf_bintime2ts(struct bintime *bt, struct bpf_ts *ts, int tstype) 2241{ 2242 struct bintime bt2; 2243 struct timeval tsm; 2244 struct timespec tsn; 2245 2246 if ((tstype & BPF_T_MONOTONIC) == 0) { 2247 bt2 = *bt; 2248 bintime_add(&bt2, &boottimebin); 2249 bt = &bt2; 2250 } 2251 switch (BPF_T_FORMAT(tstype)) { 2252 case BPF_T_MICROTIME: 2253 bintime2timeval(bt, &tsm); 2254 ts->bt_sec = tsm.tv_sec; 2255 ts->bt_frac = tsm.tv_usec; 2256 break; 2257 case BPF_T_NANOTIME: 2258 bintime2timespec(bt, &tsn); 2259 ts->bt_sec = tsn.tv_sec; 2260 ts->bt_frac = tsn.tv_nsec; 2261 break; 2262 case BPF_T_BINTIME: 2263 ts->bt_sec = bt->sec; 2264 ts->bt_frac = bt->frac; 2265 break; 2266 } 2267} 2268 2269/* 2270 * Move the packet data from interface memory (pkt) into the 2271 * store buffer. "cpfn" is the routine called to do the actual data 2272 * transfer. bcopy is passed in to copy contiguous chunks, while 2273 * bpf_append_mbuf is passed in to copy mbuf chains. In the latter case, 2274 * pkt is really an mbuf. 2275 */ 2276static void 2277catchpacket(struct bpf_d *d, u_char *pkt, u_int pktlen, u_int snaplen, 2278 void (*cpfn)(struct bpf_d *, caddr_t, u_int, void *, u_int), 2279 struct bintime *bt) 2280{ 2281 struct bpf_xhdr hdr; 2282#ifndef BURN_BRIDGES 2283 struct bpf_hdr hdr_old; 2284#ifdef COMPAT_FREEBSD32 2285 struct bpf_hdr32 hdr32_old; 2286#endif 2287#endif 2288 int caplen, curlen, hdrlen, totlen; 2289 int do_wakeup = 0; 2290 int do_timestamp; 2291 int tstype; 2292 2293 BPFD_LOCK_ASSERT(d); 2294 2295 /* 2296 * Detect whether user space has released a buffer back to us, and if 2297 * so, move it from being a hold buffer to a free buffer. This may 2298 * not be the best place to do it (for example, we might only want to 2299 * run this check if we need the space), but for now it's a reliable 2300 * spot to do it. 2301 */ 2302 if (d->bd_fbuf == NULL && bpf_canfreebuf(d)) { 2303 while (d->bd_hbuf_in_use) 2304 mtx_sleep(&d->bd_hbuf_in_use, &d->bd_lock, 2305 PRINET, "bd_hbuf", 0); 2306 d->bd_fbuf = d->bd_hbuf; 2307 d->bd_hbuf = NULL; 2308 d->bd_hlen = 0; 2309 bpf_buf_reclaimed(d); 2310 } 2311 2312 /* 2313 * Figure out how many bytes to move. If the packet is 2314 * greater or equal to the snapshot length, transfer that 2315 * much. Otherwise, transfer the whole packet (unless 2316 * we hit the buffer size limit). 2317 */ 2318 hdrlen = bpf_hdrlen(d); 2319 totlen = hdrlen + min(snaplen, pktlen); 2320 if (totlen > d->bd_bufsize) 2321 totlen = d->bd_bufsize; 2322 2323 /* 2324 * Round up the end of the previous packet to the next longword. 2325 * 2326 * Drop the packet if there's no room and no hope of room 2327 * If the packet would overflow the storage buffer or the storage 2328 * buffer is considered immutable by the buffer model, try to rotate 2329 * the buffer and wakeup pending processes. 2330 */ 2331#ifdef COMPAT_FREEBSD32 2332 if (d->bd_compat32) 2333 curlen = BPF_WORDALIGN32(d->bd_slen); 2334 else 2335#endif 2336 curlen = BPF_WORDALIGN(d->bd_slen); 2337 if (curlen + totlen > d->bd_bufsize || !bpf_canwritebuf(d)) { 2338 if (d->bd_fbuf == NULL) { 2339 /* 2340 * There's no room in the store buffer, and no 2341 * prospect of room, so drop the packet. Notify the 2342 * buffer model. 2343 */ 2344 bpf_buffull(d); 2345 ++d->bd_dcount; 2346 return; 2347 } 2348 while (d->bd_hbuf_in_use) 2349 mtx_sleep(&d->bd_hbuf_in_use, &d->bd_lock, 2350 PRINET, "bd_hbuf", 0); 2351 ROTATE_BUFFERS(d); 2352 do_wakeup = 1; 2353 curlen = 0; 2354 } else if (d->bd_immediate || d->bd_state == BPF_TIMED_OUT) 2355 /* 2356 * Immediate mode is set, or the read timeout has already 2357 * expired during a select call. A packet arrived, so the 2358 * reader should be woken up. 2359 */ 2360 do_wakeup = 1; 2361 caplen = totlen - hdrlen; 2362 tstype = d->bd_tstamp; 2363 do_timestamp = tstype != BPF_T_NONE; 2364#ifndef BURN_BRIDGES 2365 if (tstype == BPF_T_NONE || BPF_T_FORMAT(tstype) == BPF_T_MICROTIME) { 2366 struct bpf_ts ts; 2367 if (do_timestamp) 2368 bpf_bintime2ts(bt, &ts, tstype); 2369#ifdef COMPAT_FREEBSD32 2370 if (d->bd_compat32) { 2371 bzero(&hdr32_old, sizeof(hdr32_old)); 2372 if (do_timestamp) { 2373 hdr32_old.bh_tstamp.tv_sec = ts.bt_sec; 2374 hdr32_old.bh_tstamp.tv_usec = ts.bt_frac; 2375 } 2376 hdr32_old.bh_datalen = pktlen; 2377 hdr32_old.bh_hdrlen = hdrlen; 2378 hdr32_old.bh_caplen = caplen; 2379 bpf_append_bytes(d, d->bd_sbuf, curlen, &hdr32_old, 2380 sizeof(hdr32_old)); 2381 goto copy; 2382 } 2383#endif 2384 bzero(&hdr_old, sizeof(hdr_old)); 2385 if (do_timestamp) { 2386 hdr_old.bh_tstamp.tv_sec = ts.bt_sec; 2387 hdr_old.bh_tstamp.tv_usec = ts.bt_frac; 2388 } 2389 hdr_old.bh_datalen = pktlen; 2390 hdr_old.bh_hdrlen = hdrlen; 2391 hdr_old.bh_caplen = caplen; 2392 bpf_append_bytes(d, d->bd_sbuf, curlen, &hdr_old, 2393 sizeof(hdr_old)); 2394 goto copy; 2395 } 2396#endif 2397 2398 /* 2399 * Append the bpf header. Note we append the actual header size, but 2400 * move forward the length of the header plus padding. 2401 */ 2402 bzero(&hdr, sizeof(hdr)); 2403 if (do_timestamp) 2404 bpf_bintime2ts(bt, &hdr.bh_tstamp, tstype); 2405 hdr.bh_datalen = pktlen; 2406 hdr.bh_hdrlen = hdrlen; 2407 hdr.bh_caplen = caplen; 2408 bpf_append_bytes(d, d->bd_sbuf, curlen, &hdr, sizeof(hdr)); 2409 2410 /* 2411 * Copy the packet data into the store buffer and update its length. 2412 */ 2413#ifndef BURN_BRIDGES 2414copy: 2415#endif 2416 (*cpfn)(d, d->bd_sbuf, curlen + hdrlen, pkt, caplen); 2417 d->bd_slen = curlen + totlen; 2418 2419 if (do_wakeup) 2420 bpf_wakeup(d); 2421} 2422 2423/* 2424 * Free buffers currently in use by a descriptor. 2425 * Called on close. 2426 */ 2427static void 2428bpf_freed(struct bpf_d *d) 2429{ 2430 2431 /* 2432 * We don't need to lock out interrupts since this descriptor has 2433 * been detached from its interface and it yet hasn't been marked 2434 * free. 2435 */ 2436 bpf_free(d); 2437 if (d->bd_rfilter != NULL) { 2438 free((caddr_t)d->bd_rfilter, M_BPF); 2439#ifdef BPF_JITTER 2440 if (d->bd_bfilter != NULL) 2441 bpf_destroy_jit_filter(d->bd_bfilter); 2442#endif 2443 } 2444 if (d->bd_wfilter != NULL) 2445 free((caddr_t)d->bd_wfilter, M_BPF); 2446 mtx_destroy(&d->bd_lock); 2447} 2448 2449/* 2450 * Attach an interface to bpf. dlt is the link layer type; hdrlen is the 2451 * fixed size of the link header (variable length headers not yet supported). 2452 */ 2453void 2454bpfattach(struct ifnet *ifp, u_int dlt, u_int hdrlen) 2455{ 2456 2457 bpfattach2(ifp, dlt, hdrlen, &ifp->if_bpf); 2458} 2459 2460/* 2461 * Attach an interface to bpf. ifp is a pointer to the structure 2462 * defining the interface to be attached, dlt is the link layer type, 2463 * and hdrlen is the fixed size of the link header (variable length 2464 * headers are not yet supporrted). 2465 */ 2466void 2467bpfattach2(struct ifnet *ifp, u_int dlt, u_int hdrlen, struct bpf_if **driverp) 2468{ 2469 struct bpf_if *bp; 2470 2471 bp = malloc(sizeof(*bp), M_BPF, M_NOWAIT | M_ZERO); 2472 if (bp == NULL) 2473 panic("bpfattach"); 2474 2475 LIST_INIT(&bp->bif_dlist); 2476 LIST_INIT(&bp->bif_wlist); 2477 bp->bif_ifp = ifp; 2478 bp->bif_dlt = dlt; 2479 rw_init(&bp->bif_lock, "bpf interface lock"); 2480 KASSERT(*driverp == NULL, ("bpfattach2: driverp already initialized")); 2481 *driverp = bp; 2482 2483 BPF_LOCK(); 2484 LIST_INSERT_HEAD(&bpf_iflist, bp, bif_next); 2485 BPF_UNLOCK(); 2486 2487 bp->bif_hdrlen = hdrlen; 2488 2489 if (bootverbose) 2490 if_printf(ifp, "bpf attached\n"); 2491} 2492 2493/* 2494 * Detach bpf from an interface. This involves detaching each descriptor 2495 * associated with the interface. Notify each descriptor as it's detached 2496 * so that any sleepers wake up and get ENXIO. 2497 */ 2498void 2499bpfdetach(struct ifnet *ifp) 2500{ 2501 struct bpf_if *bp, *bp_temp; 2502 struct bpf_d *d; 2503 int ndetached; 2504 2505 ndetached = 0; 2506 2507 BPF_LOCK(); 2508 /* Find all bpf_if struct's which reference ifp and detach them. */ 2509 LIST_FOREACH_SAFE(bp, &bpf_iflist, bif_next, bp_temp) { 2510 if (ifp != bp->bif_ifp) 2511 continue; 2512 2513 LIST_REMOVE(bp, bif_next); 2514 /* Add to to-be-freed list */ 2515 LIST_INSERT_HEAD(&bpf_freelist, bp, bif_next); 2516 2517 ndetached++; 2518 /* 2519 * Delay freeing bp till interface is detached 2520 * and all routes through this interface are removed. 2521 * Mark bp as detached to restrict new consumers. 2522 */ 2523 BPFIF_WLOCK(bp); 2524 bp->flags |= BPFIF_FLAG_DYING; 2525 BPFIF_WUNLOCK(bp); 2526 2527 CTR4(KTR_NET, "%s: sheduling free for encap %d (%p) for if %p", 2528 __func__, bp->bif_dlt, bp, ifp); 2529 2530 /* Free common descriptors */ 2531 while ((d = LIST_FIRST(&bp->bif_dlist)) != NULL) { 2532 bpf_detachd_locked(d); 2533 BPFD_LOCK(d); 2534 bpf_wakeup(d); 2535 BPFD_UNLOCK(d); 2536 } 2537 2538 /* Free writer-only descriptors */ 2539 while ((d = LIST_FIRST(&bp->bif_wlist)) != NULL) { 2540 bpf_detachd_locked(d); 2541 BPFD_LOCK(d); 2542 bpf_wakeup(d); 2543 BPFD_UNLOCK(d); 2544 } 2545 } 2546 BPF_UNLOCK(); 2547 2548#ifdef INVARIANTS 2549 if (ndetached == 0) 2550 printf("bpfdetach: %s was not attached\n", ifp->if_xname); 2551#endif 2552} 2553 2554/* 2555 * Interface departure handler. 2556 * Note departure event does not guarantee interface is going down. 2557 * Interface renaming is currently done via departure/arrival event set. 2558 * 2559 * Departure handled is called after all routes pointing to 2560 * given interface are removed and interface is in down state 2561 * restricting any packets to be sent/received. We assume it is now safe 2562 * to free data allocated by BPF. 2563 */ 2564static void 2565bpf_ifdetach(void *arg __unused, struct ifnet *ifp) 2566{ 2567 struct bpf_if *bp, *bp_temp; 2568 int nmatched = 0; 2569 2570 BPF_LOCK(); 2571 /* 2572 * Find matching entries in free list. 2573 * Nothing should be found if bpfdetach() was not called. 2574 */ 2575 LIST_FOREACH_SAFE(bp, &bpf_freelist, bif_next, bp_temp) { 2576 if (ifp != bp->bif_ifp) 2577 continue; 2578 2579 CTR3(KTR_NET, "%s: freeing BPF instance %p for interface %p", 2580 __func__, bp, ifp); 2581 2582 LIST_REMOVE(bp, bif_next); 2583 2584 rw_destroy(&bp->bif_lock); 2585 free(bp, M_BPF); 2586 2587 nmatched++; 2588 } 2589 BPF_UNLOCK(); 2590 2591 /* 2592 * Note that we cannot zero other pointers to 2593 * custom DLTs possibly used by given interface. 2594 */ 2595 if (nmatched != 0) 2596 ifp->if_bpf = NULL; 2597} 2598 2599/* 2600 * Get a list of available data link type of the interface. 2601 */ 2602static int 2603bpf_getdltlist(struct bpf_d *d, struct bpf_dltlist *bfl) 2604{ 2605 int n, error; 2606 struct ifnet *ifp; 2607 struct bpf_if *bp; 2608 2609 BPF_LOCK_ASSERT(); 2610 2611 ifp = d->bd_bif->bif_ifp; 2612 n = 0; 2613 error = 0; 2614 LIST_FOREACH(bp, &bpf_iflist, bif_next) { 2615 if (bp->bif_ifp != ifp) 2616 continue; 2617 if (bfl->bfl_list != NULL) { 2618 if (n >= bfl->bfl_len) 2619 return (ENOMEM); 2620 error = copyout(&bp->bif_dlt, 2621 bfl->bfl_list + n, sizeof(u_int)); 2622 } 2623 n++; 2624 } 2625 bfl->bfl_len = n; 2626 return (error); 2627} 2628 2629/* 2630 * Set the data link type of a BPF instance. 2631 */ 2632static int 2633bpf_setdlt(struct bpf_d *d, u_int dlt) 2634{ 2635 int error, opromisc; 2636 struct ifnet *ifp; 2637 struct bpf_if *bp; 2638 2639 BPF_LOCK_ASSERT(); 2640 2641 if (d->bd_bif->bif_dlt == dlt) 2642 return (0); 2643 ifp = d->bd_bif->bif_ifp; 2644 2645 LIST_FOREACH(bp, &bpf_iflist, bif_next) { 2646 if (bp->bif_ifp == ifp && bp->bif_dlt == dlt) 2647 break; 2648 } 2649 2650 if (bp != NULL) { 2651 opromisc = d->bd_promisc; 2652 bpf_attachd(d, bp); 2653 BPFD_LOCK(d); 2654 reset_d(d); 2655 BPFD_UNLOCK(d); 2656 if (opromisc) { 2657 error = ifpromisc(bp->bif_ifp, 1); 2658 if (error) 2659 if_printf(bp->bif_ifp, 2660 "bpf_setdlt: ifpromisc failed (%d)\n", 2661 error); 2662 else 2663 d->bd_promisc = 1; 2664 } 2665 } 2666 return (bp == NULL ? EINVAL : 0); 2667} 2668 2669static void 2670bpf_drvinit(void *unused) 2671{ 2672 struct cdev *dev; 2673 2674 mtx_init(&bpf_mtx, "bpf global lock", NULL, MTX_DEF); 2675 LIST_INIT(&bpf_iflist); 2676 LIST_INIT(&bpf_freelist); 2677 2678 dev = make_dev(&bpf_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, "bpf"); 2679 /* For compatibility */ 2680 make_dev_alias(dev, "bpf0"); 2681 2682 /* Register interface departure handler */ 2683 bpf_ifdetach_cookie = EVENTHANDLER_REGISTER( 2684 ifnet_departure_event, bpf_ifdetach, NULL, 2685 EVENTHANDLER_PRI_ANY); 2686} 2687 2688/* 2689 * Zero out the various packet counters associated with all of the bpf 2690 * descriptors. At some point, we will probably want to get a bit more 2691 * granular and allow the user to specify descriptors to be zeroed. 2692 */ 2693static void 2694bpf_zero_counters(void) 2695{ 2696 struct bpf_if *bp; 2697 struct bpf_d *bd; 2698 2699 BPF_LOCK(); 2700 LIST_FOREACH(bp, &bpf_iflist, bif_next) { 2701 BPFIF_RLOCK(bp); 2702 LIST_FOREACH(bd, &bp->bif_dlist, bd_next) { 2703 BPFD_LOCK(bd); 2704 bd->bd_rcount = 0; 2705 bd->bd_dcount = 0; 2706 bd->bd_fcount = 0; 2707 bd->bd_wcount = 0; 2708 bd->bd_wfcount = 0; 2709 bd->bd_zcopy = 0; 2710 BPFD_UNLOCK(bd); 2711 } 2712 BPFIF_RUNLOCK(bp); 2713 } 2714 BPF_UNLOCK(); 2715} 2716 2717/* 2718 * Fill filter statistics 2719 */ 2720static void 2721bpfstats_fill_xbpf(struct xbpf_d *d, struct bpf_d *bd) 2722{ 2723 2724 bzero(d, sizeof(*d)); 2725 BPFD_LOCK_ASSERT(bd); 2726 d->bd_structsize = sizeof(*d); 2727 /* XXX: reading should be protected by global lock */ 2728 d->bd_immediate = bd->bd_immediate; 2729 d->bd_promisc = bd->bd_promisc; 2730 d->bd_hdrcmplt = bd->bd_hdrcmplt; 2731 d->bd_direction = bd->bd_direction; 2732 d->bd_feedback = bd->bd_feedback; 2733 d->bd_async = bd->bd_async; 2734 d->bd_rcount = bd->bd_rcount; 2735 d->bd_dcount = bd->bd_dcount; 2736 d->bd_fcount = bd->bd_fcount; 2737 d->bd_sig = bd->bd_sig; 2738 d->bd_slen = bd->bd_slen; 2739 d->bd_hlen = bd->bd_hlen; 2740 d->bd_bufsize = bd->bd_bufsize; 2741 d->bd_pid = bd->bd_pid; 2742 strlcpy(d->bd_ifname, 2743 bd->bd_bif->bif_ifp->if_xname, IFNAMSIZ); 2744 d->bd_locked = bd->bd_locked; 2745 d->bd_wcount = bd->bd_wcount; 2746 d->bd_wdcount = bd->bd_wdcount; 2747 d->bd_wfcount = bd->bd_wfcount; 2748 d->bd_zcopy = bd->bd_zcopy; 2749 d->bd_bufmode = bd->bd_bufmode; 2750} 2751 2752/* 2753 * Handle `netstat -B' stats request 2754 */ 2755static int 2756bpf_stats_sysctl(SYSCTL_HANDLER_ARGS) 2757{ 2758 struct xbpf_d *xbdbuf, *xbd, zerostats; 2759 int index, error; 2760 struct bpf_if *bp; 2761 struct bpf_d *bd; 2762 2763 /* 2764 * XXX This is not technically correct. It is possible for non 2765 * privileged users to open bpf devices. It would make sense 2766 * if the users who opened the devices were able to retrieve 2767 * the statistics for them, too. 2768 */ 2769 error = priv_check(req->td, PRIV_NET_BPF); 2770 if (error) 2771 return (error); 2772 /* 2773 * Check to see if the user is requesting that the counters be 2774 * zeroed out. Explicitly check that the supplied data is zeroed, 2775 * as we aren't allowing the user to set the counters currently. 2776 */ 2777 if (req->newptr != NULL) { 2778 if (req->newlen != sizeof(zerostats)) 2779 return (EINVAL); 2780 bzero(&zerostats, sizeof(zerostats)); 2781 xbd = req->newptr; 2782 if (bcmp(xbd, &zerostats, sizeof(*xbd)) != 0) 2783 return (EINVAL); 2784 bpf_zero_counters(); 2785 return (0); 2786 } 2787 if (req->oldptr == NULL) 2788 return (SYSCTL_OUT(req, 0, bpf_bpfd_cnt * sizeof(*xbd))); 2789 if (bpf_bpfd_cnt == 0) 2790 return (SYSCTL_OUT(req, 0, 0)); 2791 xbdbuf = malloc(req->oldlen, M_BPF, M_WAITOK); 2792 BPF_LOCK(); 2793 if (req->oldlen < (bpf_bpfd_cnt * sizeof(*xbd))) { 2794 BPF_UNLOCK(); 2795 free(xbdbuf, M_BPF); 2796 return (ENOMEM); 2797 } 2798 index = 0; 2799 LIST_FOREACH(bp, &bpf_iflist, bif_next) { 2800 BPFIF_RLOCK(bp); 2801 /* Send writers-only first */ 2802 LIST_FOREACH(bd, &bp->bif_wlist, bd_next) { 2803 xbd = &xbdbuf[index++]; 2804 BPFD_LOCK(bd); 2805 bpfstats_fill_xbpf(xbd, bd); 2806 BPFD_UNLOCK(bd); 2807 } 2808 LIST_FOREACH(bd, &bp->bif_dlist, bd_next) { 2809 xbd = &xbdbuf[index++]; 2810 BPFD_LOCK(bd); 2811 bpfstats_fill_xbpf(xbd, bd); 2812 BPFD_UNLOCK(bd); 2813 } 2814 BPFIF_RUNLOCK(bp); 2815 } 2816 BPF_UNLOCK(); 2817 error = SYSCTL_OUT(req, xbdbuf, index * sizeof(*xbd)); 2818 free(xbdbuf, M_BPF); 2819 return (error); 2820} 2821 2822SYSINIT(bpfdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE,bpf_drvinit,NULL); 2823 2824#else /* !DEV_BPF && !NETGRAPH_BPF */ 2825/* 2826 * NOP stubs to allow bpf-using drivers to load and function. 2827 * 2828 * A 'better' implementation would allow the core bpf functionality 2829 * to be loaded at runtime. 2830 */ 2831static struct bpf_if bp_null; 2832 2833void 2834bpf_tap(struct bpf_if *bp, u_char *pkt, u_int pktlen) 2835{ 2836} 2837 2838void 2839bpf_mtap(struct bpf_if *bp, struct mbuf *m) 2840{ 2841} 2842 2843void 2844bpf_mtap2(struct bpf_if *bp, void *d, u_int l, struct mbuf *m) 2845{ 2846} 2847 2848void 2849bpfattach(struct ifnet *ifp, u_int dlt, u_int hdrlen) 2850{ 2851 2852 bpfattach2(ifp, dlt, hdrlen, &ifp->if_bpf); 2853} 2854 2855void 2856bpfattach2(struct ifnet *ifp, u_int dlt, u_int hdrlen, struct bpf_if **driverp) 2857{ 2858 2859 *driverp = &bp_null; 2860} 2861 2862void 2863bpfdetach(struct ifnet *ifp) 2864{ 2865} 2866 2867u_int 2868bpf_filter(const struct bpf_insn *pc, u_char *p, u_int wirelen, u_int buflen) 2869{ 2870 return -1; /* "no filter" behaviour */ 2871} 2872 2873int 2874bpf_validate(const struct bpf_insn *f, int len) 2875{ 2876 return 0; /* false */ 2877} 2878 2879#endif /* !DEV_BPF && !NETGRAPH_BPF */ 2880