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 #include <net/if_var.h> 72 #define BPF_INTERNAL 73 #include <net/bpf.h> 74 #include <net/bpf_buffer.h> 75 #ifdef BPF_JITTER 76 #include <net/bpf_jitter.h> 77 #endif 78 #include <net/bpf_zerocopy.h> 79 #include <net/bpfdesc.h> 80 #include <net/vnet.h> 81 82 #include <netinet/in.h> 83 #include <netinet/if_ether.h> 84 #include <sys/kernel.h> 85 #include <sys/sysctl.h> 86 87 #include <net80211/ieee80211_freebsd.h> 88 89 #include <security/mac/mac_framework.h> 90 91 MALLOC_DEFINE(M_BPF, "BPF", "BPF data"); 92 93 #if defined(DEV_BPF) || defined(NETGRAPH_BPF) 94 95 #define PRINET 26 /* interruptible */ 96 97 #define SIZEOF_BPF_HDR(type) \ 98 (offsetof(type, bh_hdrlen) + sizeof(((type *)0)->bh_hdrlen)) 99 100 #ifdef COMPAT_FREEBSD32 101 #include <sys/mount.h> 102 #include <compat/freebsd32/freebsd32.h> 103 #define BPF_ALIGNMENT32 sizeof(int32_t) 104 #define BPF_WORDALIGN32(x) (((x)+(BPF_ALIGNMENT32-1))&~(BPF_ALIGNMENT32-1)) 105 106 #ifndef BURN_BRIDGES 107 /* 108 * 32-bit version of structure prepended to each packet. We use this header 109 * instead of the standard one for 32-bit streams. We mark the a stream as 110 * 32-bit the first time we see a 32-bit compat ioctl request. 111 */ 112 struct bpf_hdr32 { 113 struct timeval32 bh_tstamp; /* time stamp */ 114 uint32_t bh_caplen; /* length of captured portion */ 115 uint32_t bh_datalen; /* original length of packet */ 116 uint16_t bh_hdrlen; /* length of bpf header (this struct 117 plus alignment padding) */ 118 }; 119 #endif 120 121 struct bpf_program32 { 122 u_int bf_len; 123 uint32_t bf_insns; 124 }; 125 126 struct bpf_dltlist32 { 127 u_int bfl_len; 128 u_int bfl_list; 129 }; 130 131 #define BIOCSETF32 _IOW('B', 103, struct bpf_program32) 132 #define BIOCSRTIMEOUT32 _IOW('B', 109, struct timeval32) 133 #define BIOCGRTIMEOUT32 _IOR('B', 110, struct timeval32) 134 #define BIOCGDLTLIST32 _IOWR('B', 121, struct bpf_dltlist32) 135 #define BIOCSETWF32 _IOW('B', 123, struct bpf_program32) 136 #define BIOCSETFNR32 _IOW('B', 130, struct bpf_program32) 137 #endif 138 139 /* 140 * bpf_iflist is a list of BPF interface structures, each corresponding to a 141 * specific DLT. The same network interface might have several BPF interface 142 * structures registered by different layers in the stack (i.e., 802.11 143 * frames, ethernet frames, etc). 144 */ 145 static LIST_HEAD(, bpf_if) bpf_iflist, bpf_freelist; 146 static struct mtx bpf_mtx; /* bpf global lock */ 147 static int bpf_bpfd_cnt; 148 149 static void bpf_attachd(struct bpf_d *, struct bpf_if *); 150 static void bpf_detachd(struct bpf_d *); 151 static void bpf_detachd_locked(struct bpf_d *); 152 static void bpf_freed(struct bpf_d *); 153 static int bpf_movein(struct uio *, int, struct ifnet *, struct mbuf **, 154 struct sockaddr *, int *, struct bpf_insn *); 155 static int bpf_setif(struct bpf_d *, struct ifreq *); 156 static void bpf_timed_out(void *); 157 static __inline void 158 bpf_wakeup(struct bpf_d *); 159 static void catchpacket(struct bpf_d *, u_char *, u_int, u_int, 160 void (*)(struct bpf_d *, caddr_t, u_int, void *, u_int), 161 struct bintime *); 162 static void reset_d(struct bpf_d *); 163 static int bpf_setf(struct bpf_d *, struct bpf_program *, u_long cmd); 164 static int bpf_getdltlist(struct bpf_d *, struct bpf_dltlist *); 165 static int bpf_setdlt(struct bpf_d *, u_int); 166 static void filt_bpfdetach(struct knote *); 167 static int filt_bpfread(struct knote *, long); 168 static void bpf_drvinit(void *); 169 static int bpf_stats_sysctl(SYSCTL_HANDLER_ARGS); 170 171 SYSCTL_NODE(_net, OID_AUTO, bpf, CTLFLAG_RW, 0, "bpf sysctl"); 172 int bpf_maxinsns = BPF_MAXINSNS; 173 SYSCTL_INT(_net_bpf, OID_AUTO, maxinsns, CTLFLAG_RW, 174 &bpf_maxinsns, 0, "Maximum bpf program instructions"); 175 static int bpf_zerocopy_enable = 0; 176 SYSCTL_INT(_net_bpf, OID_AUTO, zerocopy_enable, CTLFLAG_RW, 177 &bpf_zerocopy_enable, 0, "Enable new zero-copy BPF buffer sessions"); 178 static SYSCTL_NODE(_net_bpf, OID_AUTO, stats, CTLFLAG_MPSAFE | CTLFLAG_RW, 179 bpf_stats_sysctl, "bpf statistics portal"); 180 181 static VNET_DEFINE(int, bpf_optimize_writers) = 0; 182 #define V_bpf_optimize_writers VNET(bpf_optimize_writers) 183 SYSCTL_INT(_net_bpf, OID_AUTO, optimize_writers, CTLFLAG_VNET | CTLFLAG_RW, 184 &VNET_NAME(bpf_optimize_writers), 0, 185 "Do not send packets until BPF program is set"); 186 187 static d_open_t bpfopen; 188 static d_read_t bpfread; 189 static d_write_t bpfwrite; 190 static d_ioctl_t bpfioctl; 191 static d_poll_t bpfpoll; 192 static d_kqfilter_t bpfkqfilter; 193 194 static struct cdevsw bpf_cdevsw = { 195 .d_version = D_VERSION, 196 .d_open = bpfopen, 197 .d_read = bpfread, 198 .d_write = bpfwrite, 199 .d_ioctl = bpfioctl, 200 .d_poll = bpfpoll, 201 .d_name = "bpf", 202 .d_kqfilter = bpfkqfilter, 203 }; 204 205 static struct filterops bpfread_filtops = { 206 .f_isfd = 1, 207 .f_detach = filt_bpfdetach, 208 .f_event = filt_bpfread, 209 }; 210 211 eventhandler_tag bpf_ifdetach_cookie = NULL; 212 213 /* 214 * LOCKING MODEL USED BY BPF: 215 * Locks: 216 * 1) global lock (BPF_LOCK). Mutex, used to protect interface addition/removal, 217 * some global counters and every bpf_if reference. 218 * 2) Interface lock. Rwlock, used to protect list of BPF descriptors and their filters. 219 * 3) Descriptor lock. Mutex, used to protect BPF buffers and various structure fields 220 * used by bpf_mtap code. 221 * 222 * Lock order: 223 * 224 * Global lock, interface lock, descriptor lock 225 * 226 * We have to acquire interface lock before descriptor main lock due to BPF_MTAP[2] 227 * working model. In many places (like bpf_detachd) we start with BPF descriptor 228 * (and we need to at least rlock it to get reliable interface pointer). This 229 * gives us potential LOR. As a result, we use global lock to protect from bpf_if 230 * change in every such place. 231 * 232 * Changing d->bd_bif is protected by 1) global lock, 2) interface lock and 233 * 3) descriptor main wlock. 234 * Reading bd_bif can be protected by any of these locks, typically global lock. 235 * 236 * Changing read/write BPF filter is protected by the same three locks, 237 * the same applies for reading. 238 * 239 * Sleeping in global lock is not allowed due to bpfdetach() using it. 240 */ 241 242 /* 243 * Wrapper functions for various buffering methods. If the set of buffer 244 * modes expands, we will probably want to introduce a switch data structure 245 * similar to protosw, et. 246 */ 247 static void 248 bpf_append_bytes(struct bpf_d *d, caddr_t buf, u_int offset, void *src, 249 u_int len) 250 { 251 252 BPFD_LOCK_ASSERT(d); 253 254 switch (d->bd_bufmode) { 255 case BPF_BUFMODE_BUFFER: 256 return (bpf_buffer_append_bytes(d, buf, offset, src, len)); 257 258 case BPF_BUFMODE_ZBUF: 259 d->bd_zcopy++; 260 return (bpf_zerocopy_append_bytes(d, buf, offset, src, len)); 261 262 default: 263 panic("bpf_buf_append_bytes"); 264 } 265 } 266 267 static void 268 bpf_append_mbuf(struct bpf_d *d, caddr_t buf, u_int offset, void *src, 269 u_int len) 270 { 271 272 BPFD_LOCK_ASSERT(d); 273 274 switch (d->bd_bufmode) { 275 case BPF_BUFMODE_BUFFER: 276 return (bpf_buffer_append_mbuf(d, buf, offset, src, len)); 277 278 case BPF_BUFMODE_ZBUF: 279 d->bd_zcopy++; 280 return (bpf_zerocopy_append_mbuf(d, buf, offset, src, len)); 281 282 default: 283 panic("bpf_buf_append_mbuf"); 284 } 285 } 286 287 /* 288 * This function gets called when the free buffer is re-assigned. 289 */ 290 static void 291 bpf_buf_reclaimed(struct bpf_d *d) 292 { 293 294 BPFD_LOCK_ASSERT(d); 295 296 switch (d->bd_bufmode) { 297 case BPF_BUFMODE_BUFFER: 298 return; 299 300 case BPF_BUFMODE_ZBUF: 301 bpf_zerocopy_buf_reclaimed(d); 302 return; 303 304 default: 305 panic("bpf_buf_reclaimed"); 306 } 307 } 308 309 /* 310 * If the buffer mechanism has a way to decide that a held buffer can be made 311 * free, then it is exposed via the bpf_canfreebuf() interface. (1) is 312 * returned if the buffer can be discarded, (0) is returned if it cannot. 313 */ 314 static int 315 bpf_canfreebuf(struct bpf_d *d) 316 { 317 318 BPFD_LOCK_ASSERT(d); 319 320 switch (d->bd_bufmode) { 321 case BPF_BUFMODE_ZBUF: 322 return (bpf_zerocopy_canfreebuf(d)); 323 } 324 return (0); 325 } 326 327 /* 328 * Allow the buffer model to indicate that the current store buffer is 329 * immutable, regardless of the appearance of space. Return (1) if the 330 * buffer is writable, and (0) if not. 331 */ 332 static int 333 bpf_canwritebuf(struct bpf_d *d) 334 { 335 BPFD_LOCK_ASSERT(d); 336 337 switch (d->bd_bufmode) { 338 case BPF_BUFMODE_ZBUF: 339 return (bpf_zerocopy_canwritebuf(d)); 340 } 341 return (1); 342 } 343 344 /* 345 * Notify buffer model that an attempt to write to the store buffer has 346 * resulted in a dropped packet, in which case the buffer may be considered 347 * full. 348 */ 349 static void 350 bpf_buffull(struct bpf_d *d) 351 { 352 353 BPFD_LOCK_ASSERT(d); 354 355 switch (d->bd_bufmode) { 356 case BPF_BUFMODE_ZBUF: 357 bpf_zerocopy_buffull(d); 358 break; 359 } 360 } 361 362 /* 363 * Notify the buffer model that a buffer has moved into the hold position. 364 */ 365 void 366 bpf_bufheld(struct bpf_d *d) 367 { 368 369 BPFD_LOCK_ASSERT(d); 370 371 switch (d->bd_bufmode) { 372 case BPF_BUFMODE_ZBUF: 373 bpf_zerocopy_bufheld(d); 374 break; 375 } 376 } 377 378 static void 379 bpf_free(struct bpf_d *d) 380 { 381 382 switch (d->bd_bufmode) { 383 case BPF_BUFMODE_BUFFER: 384 return (bpf_buffer_free(d)); 385 386 case BPF_BUFMODE_ZBUF: 387 return (bpf_zerocopy_free(d)); 388 389 default: 390 panic("bpf_buf_free"); 391 } 392 } 393 394 static int 395 bpf_uiomove(struct bpf_d *d, caddr_t buf, u_int len, struct uio *uio) 396 { 397 398 if (d->bd_bufmode != BPF_BUFMODE_BUFFER) 399 return (EOPNOTSUPP); 400 return (bpf_buffer_uiomove(d, buf, len, uio)); 401 } 402 403 static int 404 bpf_ioctl_sblen(struct bpf_d *d, u_int *i) 405 { 406 407 if (d->bd_bufmode != BPF_BUFMODE_BUFFER) 408 return (EOPNOTSUPP); 409 return (bpf_buffer_ioctl_sblen(d, i)); 410 } 411 412 static int 413 bpf_ioctl_getzmax(struct thread *td, struct bpf_d *d, size_t *i) 414 { 415 416 if (d->bd_bufmode != BPF_BUFMODE_ZBUF) 417 return (EOPNOTSUPP); 418 return (bpf_zerocopy_ioctl_getzmax(td, d, i)); 419 } 420 421 static int 422 bpf_ioctl_rotzbuf(struct thread *td, struct bpf_d *d, struct bpf_zbuf *bz) 423 { 424 425 if (d->bd_bufmode != BPF_BUFMODE_ZBUF) 426 return (EOPNOTSUPP); 427 return (bpf_zerocopy_ioctl_rotzbuf(td, d, bz)); 428 } 429 430 static int 431 bpf_ioctl_setzbuf(struct thread *td, struct bpf_d *d, struct bpf_zbuf *bz) 432 { 433 434 if (d->bd_bufmode != BPF_BUFMODE_ZBUF) 435 return (EOPNOTSUPP); 436 return (bpf_zerocopy_ioctl_setzbuf(td, d, bz)); 437 } 438 439 /* 440 * General BPF functions. 441 */ 442 static int 443 bpf_movein(struct uio *uio, int linktype, struct ifnet *ifp, struct mbuf **mp, 444 struct sockaddr *sockp, int *hdrlen, struct bpf_insn *wfilter) 445 { 446 const struct ieee80211_bpf_params *p; 447 struct ether_header *eh; 448 struct mbuf *m; 449 int error; 450 int len; 451 int hlen; 452 int slen; 453 454 /* 455 * Build a sockaddr based on the data link layer type. 456 * We do this at this level because the ethernet header 457 * is copied directly into the data field of the sockaddr. 458 * In the case of SLIP, there is no header and the packet 459 * is forwarded as is. 460 * Also, we are careful to leave room at the front of the mbuf 461 * for the link level header. 462 */ 463 switch (linktype) { 464 465 case DLT_SLIP: 466 sockp->sa_family = AF_INET; 467 hlen = 0; 468 break; 469 470 case DLT_EN10MB: 471 sockp->sa_family = AF_UNSPEC; 472 /* XXX Would MAXLINKHDR be better? */ 473 hlen = ETHER_HDR_LEN; 474 break; 475 476 case DLT_FDDI: 477 sockp->sa_family = AF_IMPLINK; 478 hlen = 0; 479 break; 480 481 case DLT_RAW: 482 sockp->sa_family = AF_UNSPEC; 483 hlen = 0; 484 break; 485 486 case DLT_NULL: 487 /* 488 * null interface types require a 4 byte pseudo header which 489 * corresponds to the address family of the packet. 490 */ 491 sockp->sa_family = AF_UNSPEC; 492 hlen = 4; 493 break; 494 495 case DLT_ATM_RFC1483: 496 /* 497 * en atm driver requires 4-byte atm pseudo header. 498 * though it isn't standard, vpi:vci needs to be 499 * specified anyway. 500 */ 501 sockp->sa_family = AF_UNSPEC; 502 hlen = 12; /* XXX 4(ATM_PH) + 3(LLC) + 5(SNAP) */ 503 break; 504 505 case DLT_PPP: 506 sockp->sa_family = AF_UNSPEC; 507 hlen = 4; /* This should match PPP_HDRLEN */ 508 break; 509 510 case DLT_IEEE802_11: /* IEEE 802.11 wireless */ 511 sockp->sa_family = AF_IEEE80211; 512 hlen = 0; 513 break; 514 515 case DLT_IEEE802_11_RADIO: /* IEEE 802.11 wireless w/ phy params */ 516 sockp->sa_family = AF_IEEE80211; 517 sockp->sa_len = 12; /* XXX != 0 */ 518 hlen = sizeof(struct ieee80211_bpf_params); 519 break; 520 521 default: 522 return (EIO); 523 } 524 525 len = uio->uio_resid; 526 if (len < hlen || len - hlen > ifp->if_mtu) 527 return (EMSGSIZE); 528 529 m = m_get2(len, M_WAITOK, MT_DATA, M_PKTHDR); 530 if (m == NULL) 531 return (EIO); 532 m->m_pkthdr.len = m->m_len = len; 533 *mp = m; 534 535 error = uiomove(mtod(m, u_char *), len, uio); 536 if (error) 537 goto bad; 538 539 slen = bpf_filter(wfilter, mtod(m, u_char *), len, len); 540 if (slen == 0) { 541 error = EPERM; 542 goto bad; 543 } 544 545 /* Check for multicast destination */ 546 switch (linktype) { 547 case DLT_EN10MB: 548 eh = mtod(m, struct ether_header *); 549 if (ETHER_IS_MULTICAST(eh->ether_dhost)) { 550 if (bcmp(ifp->if_broadcastaddr, eh->ether_dhost, 551 ETHER_ADDR_LEN) == 0) 552 m->m_flags |= M_BCAST; 553 else 554 m->m_flags |= M_MCAST; 555 } 556 break; 557 } 558 559 /* 560 * Make room for link header, and copy it to sockaddr 561 */ 562 if (hlen != 0) { 563 if (sockp->sa_family == AF_IEEE80211) { 564 /* 565 * Collect true length from the parameter header 566 * NB: sockp is known to be zero'd so if we do a 567 * short copy unspecified parameters will be 568 * zero. 569 * NB: packet may not be aligned after stripping 570 * bpf params 571 * XXX check ibp_vers 572 */ 573 p = mtod(m, const struct ieee80211_bpf_params *); 574 hlen = p->ibp_len; 575 if (hlen > sizeof(sockp->sa_data)) { 576 error = EINVAL; 577 goto bad; 578 } 579 } 580 bcopy(mtod(m, const void *), sockp->sa_data, hlen); 581 } 582 *hdrlen = hlen; 583 584 return (0); 585 bad: 586 m_freem(m); 587 return (error); 588 } 589 590 /* 591 * Attach file to the bpf interface, i.e. make d listen on bp. 592 */ 593 static void 594 bpf_attachd(struct bpf_d *d, struct bpf_if *bp) 595 { 596 int op_w; 597 598 BPF_LOCK_ASSERT(); 599 600 /* 601 * Save sysctl value to protect from sysctl change 602 * between reads 603 */ 604 op_w = V_bpf_optimize_writers; 605 606 if (d->bd_bif != NULL) 607 bpf_detachd_locked(d); 608 /* 609 * Point d at bp, and add d to the interface's list. 610 * Since there are many applicaiotns using BPF for 611 * sending raw packets only (dhcpd, cdpd are good examples) 612 * we can delay adding d to the list of active listeners until 613 * some filter is configured. 614 */ 615 616 BPFIF_WLOCK(bp); 617 BPFD_LOCK(d); 618 619 d->bd_bif = bp; 620 621 if (op_w != 0) { 622 /* Add to writers-only list */ 623 LIST_INSERT_HEAD(&bp->bif_wlist, d, bd_next); 624 /* 625 * We decrement bd_writer on every filter set operation. 626 * First BIOCSETF is done by pcap_open_live() to set up 627 * snap length. After that appliation usually sets its own filter 628 */ 629 d->bd_writer = 2; 630 } else 631 LIST_INSERT_HEAD(&bp->bif_dlist, d, bd_next); 632 633 BPFD_UNLOCK(d); 634 BPFIF_WUNLOCK(bp); 635 636 bpf_bpfd_cnt++; 637 638 CTR3(KTR_NET, "%s: bpf_attach called by pid %d, adding to %s list", 639 __func__, d->bd_pid, d->bd_writer ? "writer" : "active"); 640 641 if (op_w == 0) 642 EVENTHANDLER_INVOKE(bpf_track, bp->bif_ifp, bp->bif_dlt, 1); 643 } 644 645 /* 646 * Check if we need to upgrade our descriptor @d from write-only mode. 647 */ 648 static int 649 bpf_check_upgrade(u_long cmd, struct bpf_d *d, struct bpf_insn *fcode, int flen) 650 { 651 int is_snap, need_upgrade; 652 653 /* 654 * Check if we've already upgraded or new filter is empty. 655 */ 656 if (d->bd_writer == 0 || fcode == NULL) 657 return (0); 658 659 need_upgrade = 0; 660 661 /* 662 * Check if cmd looks like snaplen setting from 663 * pcap_bpf.c:pcap_open_live(). 664 * Note we're not checking .k value here: 665 * while pcap_open_live() definitely sets to to non-zero value, 666 * we'd prefer to treat k=0 (deny ALL) case the same way: e.g. 667 * do not consider upgrading immediately 668 */ 669 if (cmd == BIOCSETF && flen == 1 && fcode[0].code == (BPF_RET | BPF_K)) 670 is_snap = 1; 671 else 672 is_snap = 0; 673 674 if (is_snap == 0) { 675 /* 676 * We're setting first filter and it doesn't look like 677 * setting snaplen. We're probably using bpf directly. 678 * Upgrade immediately. 679 */ 680 need_upgrade = 1; 681 } else { 682 /* 683 * Do not require upgrade by first BIOCSETF 684 * (used to set snaplen) by pcap_open_live(). 685 */ 686 687 if (--d->bd_writer == 0) { 688 /* 689 * First snaplen filter has already 690 * been set. This is probably catch-all 691 * filter 692 */ 693 need_upgrade = 1; 694 } 695 } 696 697 CTR5(KTR_NET, 698 "%s: filter function set by pid %d, " 699 "bd_writer counter %d, snap %d upgrade %d", 700 __func__, d->bd_pid, d->bd_writer, 701 is_snap, need_upgrade); 702 703 return (need_upgrade); 704 } 705 706 /* 707 * Add d to the list of active bp filters. 708 * Reuqires bpf_attachd() to be called before 709 */ 710 static void 711 bpf_upgraded(struct bpf_d *d) 712 { 713 struct bpf_if *bp; 714 715 BPF_LOCK_ASSERT(); 716 717 bp = d->bd_bif; 718 719 /* 720 * Filter can be set several times without specifying interface. 721 * Mark d as reader and exit. 722 */ 723 if (bp == NULL) { 724 BPFD_LOCK(d); 725 d->bd_writer = 0; 726 BPFD_UNLOCK(d); 727 return; 728 } 729 730 BPFIF_WLOCK(bp); 731 BPFD_LOCK(d); 732 733 /* Remove from writers-only list */ 734 LIST_REMOVE(d, bd_next); 735 LIST_INSERT_HEAD(&bp->bif_dlist, d, bd_next); 736 /* Mark d as reader */ 737 d->bd_writer = 0; 738 739 BPFD_UNLOCK(d); 740 BPFIF_WUNLOCK(bp); 741 742 CTR2(KTR_NET, "%s: upgrade required by pid %d", __func__, d->bd_pid); 743 744 EVENTHANDLER_INVOKE(bpf_track, bp->bif_ifp, bp->bif_dlt, 1); 745 } 746 747 /* 748 * Detach a file from its interface. 749 */ 750 static void 751 bpf_detachd(struct bpf_d *d) 752 { 753 BPF_LOCK(); 754 bpf_detachd_locked(d); 755 BPF_UNLOCK(); 756 } 757 758 static void 759 bpf_detachd_locked(struct bpf_d *d) 760 { 761 int error; 762 struct bpf_if *bp; 763 struct ifnet *ifp; 764 765 CTR2(KTR_NET, "%s: detach required by pid %d", __func__, d->bd_pid); 766 767 BPF_LOCK_ASSERT(); 768 769 /* Check if descriptor is attached */ 770 if ((bp = d->bd_bif) == NULL) 771 return; 772 773 BPFIF_WLOCK(bp); 774 BPFD_LOCK(d); 775 776 /* Save bd_writer value */ 777 error = d->bd_writer; 778 779 /* 780 * Remove d from the interface's descriptor list. 781 */ 782 LIST_REMOVE(d, bd_next); 783 784 ifp = bp->bif_ifp; 785 d->bd_bif = NULL; 786 BPFD_UNLOCK(d); 787 BPFIF_WUNLOCK(bp); 788 789 bpf_bpfd_cnt--; 790 791 /* Call event handler iff d is attached */ 792 if (error == 0) 793 EVENTHANDLER_INVOKE(bpf_track, ifp, bp->bif_dlt, 0); 794 795 /* 796 * Check if this descriptor had requested promiscuous mode. 797 * If so, turn it off. 798 */ 799 if (d->bd_promisc) { 800 d->bd_promisc = 0; 801 CURVNET_SET(ifp->if_vnet); 802 error = ifpromisc(ifp, 0); 803 CURVNET_RESTORE(); 804 if (error != 0 && error != ENXIO) { 805 /* 806 * ENXIO can happen if a pccard is unplugged 807 * Something is really wrong if we were able to put 808 * the driver into promiscuous mode, but can't 809 * take it out. 810 */ 811 if_printf(bp->bif_ifp, 812 "bpf_detach: ifpromisc failed (%d)\n", error); 813 } 814 } 815 } 816 817 /* 818 * Close the descriptor by detaching it from its interface, 819 * deallocating its buffers, and marking it free. 820 */ 821 static void 822 bpf_dtor(void *data) 823 { 824 struct bpf_d *d = data; 825 826 BPFD_LOCK(d); 827 if (d->bd_state == BPF_WAITING) 828 callout_stop(&d->bd_callout); 829 d->bd_state = BPF_IDLE; 830 BPFD_UNLOCK(d); 831 funsetown(&d->bd_sigio); 832 bpf_detachd(d); 833 #ifdef MAC 834 mac_bpfdesc_destroy(d); 835 #endif /* MAC */ 836 seldrain(&d->bd_sel); 837 knlist_destroy(&d->bd_sel.si_note); 838 callout_drain(&d->bd_callout); 839 bpf_freed(d); 840 free(d, M_BPF); 841 } 842 843 /* 844 * Open ethernet device. Returns ENXIO for illegal minor device number, 845 * EBUSY if file is open by another process. 846 */ 847 /* ARGSUSED */ 848 static int 849 bpfopen(struct cdev *dev, int flags, int fmt, struct thread *td) 850 { 851 struct bpf_d *d; 852 int error, size; 853 854 d = malloc(sizeof(*d), M_BPF, M_WAITOK | M_ZERO); 855 error = devfs_set_cdevpriv(d, bpf_dtor); 856 if (error != 0) { 857 free(d, M_BPF); 858 return (error); 859 } 860 861 /* 862 * For historical reasons, perform a one-time initialization call to 863 * the buffer routines, even though we're not yet committed to a 864 * particular buffer method. 865 */ 866 bpf_buffer_init(d); 867 d->bd_hbuf_in_use = 0; 868 d->bd_bufmode = BPF_BUFMODE_BUFFER; 869 d->bd_sig = SIGIO; 870 d->bd_direction = BPF_D_INOUT; 871 BPF_PID_REFRESH(d, td); 872 #ifdef MAC 873 mac_bpfdesc_init(d); 874 mac_bpfdesc_create(td->td_ucred, d); 875 #endif 876 mtx_init(&d->bd_lock, devtoname(dev), "bpf cdev lock", MTX_DEF); 877 callout_init_mtx(&d->bd_callout, &d->bd_lock, 0); 878 knlist_init_mtx(&d->bd_sel.si_note, &d->bd_lock); 879 880 /* Allocate default buffers */ 881 size = d->bd_bufsize; 882 bpf_buffer_ioctl_sblen(d, &size); 883 884 return (0); 885 } 886 887 /* 888 * bpfread - read next chunk of packets from buffers 889 */ 890 static int 891 bpfread(struct cdev *dev, struct uio *uio, int ioflag) 892 { 893 struct bpf_d *d; 894 int error; 895 int non_block; 896 int timed_out; 897 898 error = devfs_get_cdevpriv((void **)&d); 899 if (error != 0) 900 return (error); 901 902 /* 903 * Restrict application to use a buffer the same size as 904 * as kernel buffers. 905 */ 906 if (uio->uio_resid != d->bd_bufsize) 907 return (EINVAL); 908 909 non_block = ((ioflag & O_NONBLOCK) != 0); 910 911 BPFD_LOCK(d); 912 BPF_PID_REFRESH_CUR(d); 913 if (d->bd_bufmode != BPF_BUFMODE_BUFFER) { 914 BPFD_UNLOCK(d); 915 return (EOPNOTSUPP); 916 } 917 if (d->bd_state == BPF_WAITING) 918 callout_stop(&d->bd_callout); 919 timed_out = (d->bd_state == BPF_TIMED_OUT); 920 d->bd_state = BPF_IDLE; 921 while (d->bd_hbuf_in_use) { 922 error = mtx_sleep(&d->bd_hbuf_in_use, &d->bd_lock, 923 PRINET|PCATCH, "bd_hbuf", 0); 924 if (error != 0) { 925 BPFD_UNLOCK(d); 926 return (error); 927 } 928 } 929 /* 930 * If the hold buffer is empty, then do a timed sleep, which 931 * ends when the timeout expires or when enough packets 932 * have arrived to fill the store buffer. 933 */ 934 while (d->bd_hbuf == NULL) { 935 if (d->bd_slen != 0) { 936 /* 937 * A packet(s) either arrived since the previous 938 * read or arrived while we were asleep. 939 */ 940 if (d->bd_immediate || non_block || timed_out) { 941 /* 942 * Rotate the buffers and return what's here 943 * if we are in immediate mode, non-blocking 944 * flag is set, or this descriptor timed out. 945 */ 946 ROTATE_BUFFERS(d); 947 break; 948 } 949 } 950 951 /* 952 * No data is available, check to see if the bpf device 953 * is still pointed at a real interface. If not, return 954 * ENXIO so that the userland process knows to rebind 955 * it before using it again. 956 */ 957 if (d->bd_bif == NULL) { 958 BPFD_UNLOCK(d); 959 return (ENXIO); 960 } 961 962 if (non_block) { 963 BPFD_UNLOCK(d); 964 return (EWOULDBLOCK); 965 } 966 error = msleep(d, &d->bd_lock, PRINET|PCATCH, 967 "bpf", d->bd_rtout); 968 if (error == EINTR || error == ERESTART) { 969 BPFD_UNLOCK(d); 970 return (error); 971 } 972 if (error == EWOULDBLOCK) { 973 /* 974 * On a timeout, return what's in the buffer, 975 * which may be nothing. If there is something 976 * in the store buffer, we can rotate the buffers. 977 */ 978 if (d->bd_hbuf) 979 /* 980 * We filled up the buffer in between 981 * getting the timeout and arriving 982 * here, so we don't need to rotate. 983 */ 984 break; 985 986 if (d->bd_slen == 0) { 987 BPFD_UNLOCK(d); 988 return (0); 989 } 990 ROTATE_BUFFERS(d); 991 break; 992 } 993 } 994 /* 995 * At this point, we know we have something in the hold slot. 996 */ 997 d->bd_hbuf_in_use = 1; 998 BPFD_UNLOCK(d); 999 1000 /* 1001 * Move data from hold buffer into user space. 1002 * We know the entire buffer is transferred since 1003 * we checked above that the read buffer is bpf_bufsize bytes. 1004 * 1005 * We do not have to worry about simultaneous reads because 1006 * we waited for sole access to the hold buffer above. 1007 */ 1008 error = bpf_uiomove(d, d->bd_hbuf, d->bd_hlen, uio); 1009 1010 BPFD_LOCK(d); 1011 KASSERT(d->bd_hbuf != NULL, ("bpfread: lost bd_hbuf")); 1012 d->bd_fbuf = d->bd_hbuf; 1013 d->bd_hbuf = NULL; 1014 d->bd_hlen = 0; 1015 bpf_buf_reclaimed(d); 1016 d->bd_hbuf_in_use = 0; 1017 wakeup(&d->bd_hbuf_in_use); 1018 BPFD_UNLOCK(d); 1019 1020 return (error); 1021 } 1022 1023 /* 1024 * If there are processes sleeping on this descriptor, wake them up. 1025 */ 1026 static __inline void 1027 bpf_wakeup(struct bpf_d *d) 1028 { 1029 1030 BPFD_LOCK_ASSERT(d); 1031 if (d->bd_state == BPF_WAITING) { 1032 callout_stop(&d->bd_callout); 1033 d->bd_state = BPF_IDLE; 1034 } 1035 wakeup(d); 1036 if (d->bd_async && d->bd_sig && d->bd_sigio) 1037 pgsigio(&d->bd_sigio, d->bd_sig, 0); 1038 1039 selwakeuppri(&d->bd_sel, PRINET); 1040 KNOTE_LOCKED(&d->bd_sel.si_note, 0); 1041 } 1042 1043 static void 1044 bpf_timed_out(void *arg) 1045 { 1046 struct bpf_d *d = (struct bpf_d *)arg; 1047 1048 BPFD_LOCK_ASSERT(d); 1049 1050 if (callout_pending(&d->bd_callout) || !callout_active(&d->bd_callout)) 1051 return; 1052 if (d->bd_state == BPF_WAITING) { 1053 d->bd_state = BPF_TIMED_OUT; 1054 if (d->bd_slen != 0) 1055 bpf_wakeup(d); 1056 } 1057 } 1058 1059 static int 1060 bpf_ready(struct bpf_d *d) 1061 { 1062 1063 BPFD_LOCK_ASSERT(d); 1064 1065 if (!bpf_canfreebuf(d) && d->bd_hlen != 0) 1066 return (1); 1067 if ((d->bd_immediate || d->bd_state == BPF_TIMED_OUT) && 1068 d->bd_slen != 0) 1069 return (1); 1070 return (0); 1071 } 1072 1073 static int 1074 bpfwrite(struct cdev *dev, struct uio *uio, int ioflag) 1075 { 1076 struct bpf_d *d; 1077 struct ifnet *ifp; 1078 struct mbuf *m, *mc; 1079 struct sockaddr dst; 1080 int error, hlen; 1081 1082 error = devfs_get_cdevpriv((void **)&d); 1083 if (error != 0) 1084 return (error); 1085 1086 BPF_PID_REFRESH_CUR(d); 1087 d->bd_wcount++; 1088 /* XXX: locking required */ 1089 if (d->bd_bif == NULL) { 1090 d->bd_wdcount++; 1091 return (ENXIO); 1092 } 1093 1094 ifp = d->bd_bif->bif_ifp; 1095 1096 if ((ifp->if_flags & IFF_UP) == 0) { 1097 d->bd_wdcount++; 1098 return (ENETDOWN); 1099 } 1100 1101 if (uio->uio_resid == 0) { 1102 d->bd_wdcount++; 1103 return (0); 1104 } 1105 1106 bzero(&dst, sizeof(dst)); 1107 m = NULL; 1108 hlen = 0; 1109 /* XXX: bpf_movein() can sleep */ 1110 error = bpf_movein(uio, (int)d->bd_bif->bif_dlt, ifp, 1111 &m, &dst, &hlen, d->bd_wfilter); 1112 if (error) { 1113 d->bd_wdcount++; 1114 return (error); 1115 } 1116 d->bd_wfcount++; 1117 if (d->bd_hdrcmplt) 1118 dst.sa_family = pseudo_AF_HDRCMPLT; 1119 1120 if (d->bd_feedback) { 1121 mc = m_dup(m, M_NOWAIT); 1122 if (mc != NULL) 1123 mc->m_pkthdr.rcvif = ifp; 1124 /* Set M_PROMISC for outgoing packets to be discarded. */ 1125 if (d->bd_direction == BPF_D_INOUT) 1126 m->m_flags |= M_PROMISC; 1127 } else 1128 mc = NULL; 1129 1130 m->m_pkthdr.len -= hlen; 1131 m->m_len -= hlen; 1132 m->m_data += hlen; /* XXX */ 1133 1134 CURVNET_SET(ifp->if_vnet); 1135 #ifdef MAC 1136 BPFD_LOCK(d); 1137 mac_bpfdesc_create_mbuf(d, m); 1138 if (mc != NULL) 1139 mac_bpfdesc_create_mbuf(d, mc); 1140 BPFD_UNLOCK(d); 1141 #endif 1142 1143 error = (*ifp->if_output)(ifp, m, &dst, NULL); 1144 if (error) 1145 d->bd_wdcount++; 1146 1147 if (mc != NULL) { 1148 if (error == 0) 1149 (*ifp->if_input)(ifp, mc); 1150 else 1151 m_freem(mc); 1152 } 1153 CURVNET_RESTORE(); 1154 1155 return (error); 1156 } 1157 1158 /* 1159 * Reset a descriptor by flushing its packet buffer and clearing the receive 1160 * and drop counts. This is doable for kernel-only buffers, but with 1161 * zero-copy buffers, we can't write to (or rotate) buffers that are 1162 * currently owned by userspace. It would be nice if we could encapsulate 1163 * this logic in the buffer code rather than here. 1164 */ 1165 static void 1166 reset_d(struct bpf_d *d) 1167 { 1168 1169 BPFD_LOCK_ASSERT(d); 1170 1171 while (d->bd_hbuf_in_use) 1172 mtx_sleep(&d->bd_hbuf_in_use, &d->bd_lock, PRINET, 1173 "bd_hbuf", 0); 1174 if ((d->bd_hbuf != NULL) && 1175 (d->bd_bufmode != BPF_BUFMODE_ZBUF || bpf_canfreebuf(d))) { 1176 /* Free the hold buffer. */ 1177 d->bd_fbuf = d->bd_hbuf; 1178 d->bd_hbuf = NULL; 1179 d->bd_hlen = 0; 1180 bpf_buf_reclaimed(d); 1181 } 1182 if (bpf_canwritebuf(d)) 1183 d->bd_slen = 0; 1184 d->bd_rcount = 0; 1185 d->bd_dcount = 0; 1186 d->bd_fcount = 0; 1187 d->bd_wcount = 0; 1188 d->bd_wfcount = 0; 1189 d->bd_wdcount = 0; 1190 d->bd_zcopy = 0; 1191 } 1192 1193 /* 1194 * FIONREAD Check for read packet available. 1195 * SIOCGIFADDR Get interface address - convenient hook to driver. 1196 * BIOCGBLEN Get buffer len [for read()]. 1197 * BIOCSETF Set read filter. 1198 * BIOCSETFNR Set read filter without resetting descriptor. 1199 * BIOCSETWF Set write filter. 1200 * BIOCFLUSH Flush read packet buffer. 1201 * BIOCPROMISC Put interface into promiscuous mode. 1202 * BIOCGDLT Get link layer type. 1203 * BIOCGETIF Get interface name. 1204 * BIOCSETIF Set interface. 1205 * BIOCSRTIMEOUT Set read timeout. 1206 * BIOCGRTIMEOUT Get read timeout. 1207 * BIOCGSTATS Get packet stats. 1208 * BIOCIMMEDIATE Set immediate mode. 1209 * BIOCVERSION Get filter language version. 1210 * BIOCGHDRCMPLT Get "header already complete" flag 1211 * BIOCSHDRCMPLT Set "header already complete" flag 1212 * BIOCGDIRECTION Get packet direction flag 1213 * BIOCSDIRECTION Set packet direction flag 1214 * BIOCGTSTAMP Get time stamp format and resolution. 1215 * BIOCSTSTAMP Set time stamp format and resolution. 1216 * BIOCLOCK Set "locked" flag 1217 * BIOCFEEDBACK Set packet feedback mode. 1218 * BIOCSETZBUF Set current zero-copy buffer locations. 1219 * BIOCGETZMAX Get maximum zero-copy buffer size. 1220 * BIOCROTZBUF Force rotation of zero-copy buffer 1221 * BIOCSETBUFMODE Set buffer mode. 1222 * BIOCGETBUFMODE Get current buffer mode. 1223 */ 1224 /* ARGSUSED */ 1225 static int 1226 bpfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, 1227 struct thread *td) 1228 { 1229 struct bpf_d *d; 1230 int error; 1231 1232 error = devfs_get_cdevpriv((void **)&d); 1233 if (error != 0) 1234 return (error); 1235 1236 /* 1237 * Refresh PID associated with this descriptor. 1238 */ 1239 BPFD_LOCK(d); 1240 BPF_PID_REFRESH(d, td); 1241 if (d->bd_state == BPF_WAITING) 1242 callout_stop(&d->bd_callout); 1243 d->bd_state = BPF_IDLE; 1244 BPFD_UNLOCK(d); 1245 1246 if (d->bd_locked == 1) { 1247 switch (cmd) { 1248 case BIOCGBLEN: 1249 case BIOCFLUSH: 1250 case BIOCGDLT: 1251 case BIOCGDLTLIST: 1252 #ifdef COMPAT_FREEBSD32 1253 case BIOCGDLTLIST32: 1254 #endif 1255 case BIOCGETIF: 1256 case BIOCGRTIMEOUT: 1257 #if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1258 case BIOCGRTIMEOUT32: 1259 #endif 1260 case BIOCGSTATS: 1261 case BIOCVERSION: 1262 case BIOCGRSIG: 1263 case BIOCGHDRCMPLT: 1264 case BIOCSTSTAMP: 1265 case BIOCFEEDBACK: 1266 case FIONREAD: 1267 case BIOCLOCK: 1268 case BIOCSRTIMEOUT: 1269 #if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1270 case BIOCSRTIMEOUT32: 1271 #endif 1272 case BIOCIMMEDIATE: 1273 case TIOCGPGRP: 1274 case BIOCROTZBUF: 1275 break; 1276 default: 1277 return (EPERM); 1278 } 1279 } 1280 #ifdef COMPAT_FREEBSD32 1281 /* 1282 * If we see a 32-bit compat ioctl, mark the stream as 32-bit so 1283 * that it will get 32-bit packet headers. 1284 */ 1285 switch (cmd) { 1286 case BIOCSETF32: 1287 case BIOCSETFNR32: 1288 case BIOCSETWF32: 1289 case BIOCGDLTLIST32: 1290 case BIOCGRTIMEOUT32: 1291 case BIOCSRTIMEOUT32: 1292 BPFD_LOCK(d); 1293 d->bd_compat32 = 1; 1294 BPFD_UNLOCK(d); 1295 } 1296 #endif 1297 1298 CURVNET_SET(TD_TO_VNET(td)); 1299 switch (cmd) { 1300 1301 default: 1302 error = EINVAL; 1303 break; 1304 1305 /* 1306 * Check for read packet available. 1307 */ 1308 case FIONREAD: 1309 { 1310 int n; 1311 1312 BPFD_LOCK(d); 1313 n = d->bd_slen; 1314 while (d->bd_hbuf_in_use) 1315 mtx_sleep(&d->bd_hbuf_in_use, &d->bd_lock, 1316 PRINET, "bd_hbuf", 0); 1317 if (d->bd_hbuf) 1318 n += d->bd_hlen; 1319 BPFD_UNLOCK(d); 1320 1321 *(int *)addr = n; 1322 break; 1323 } 1324 1325 case SIOCGIFADDR: 1326 { 1327 struct ifnet *ifp; 1328 1329 if (d->bd_bif == NULL) 1330 error = EINVAL; 1331 else { 1332 ifp = d->bd_bif->bif_ifp; 1333 error = (*ifp->if_ioctl)(ifp, cmd, addr); 1334 } 1335 break; 1336 } 1337 1338 /* 1339 * Get buffer len [for read()]. 1340 */ 1341 case BIOCGBLEN: 1342 BPFD_LOCK(d); 1343 *(u_int *)addr = d->bd_bufsize; 1344 BPFD_UNLOCK(d); 1345 break; 1346 1347 /* 1348 * Set buffer length. 1349 */ 1350 case BIOCSBLEN: 1351 error = bpf_ioctl_sblen(d, (u_int *)addr); 1352 break; 1353 1354 /* 1355 * Set link layer read filter. 1356 */ 1357 case BIOCSETF: 1358 case BIOCSETFNR: 1359 case BIOCSETWF: 1360 #ifdef COMPAT_FREEBSD32 1361 case BIOCSETF32: 1362 case BIOCSETFNR32: 1363 case BIOCSETWF32: 1364 #endif 1365 error = bpf_setf(d, (struct bpf_program *)addr, cmd); 1366 break; 1367 1368 /* 1369 * Flush read packet buffer. 1370 */ 1371 case BIOCFLUSH: 1372 BPFD_LOCK(d); 1373 reset_d(d); 1374 BPFD_UNLOCK(d); 1375 break; 1376 1377 /* 1378 * Put interface into promiscuous mode. 1379 */ 1380 case BIOCPROMISC: 1381 if (d->bd_bif == NULL) { 1382 /* 1383 * No interface attached yet. 1384 */ 1385 error = EINVAL; 1386 break; 1387 } 1388 if (d->bd_promisc == 0) { 1389 error = ifpromisc(d->bd_bif->bif_ifp, 1); 1390 if (error == 0) 1391 d->bd_promisc = 1; 1392 } 1393 break; 1394 1395 /* 1396 * Get current data link type. 1397 */ 1398 case BIOCGDLT: 1399 BPF_LOCK(); 1400 if (d->bd_bif == NULL) 1401 error = EINVAL; 1402 else 1403 *(u_int *)addr = d->bd_bif->bif_dlt; 1404 BPF_UNLOCK(); 1405 break; 1406 1407 /* 1408 * Get a list of supported data link types. 1409 */ 1410 #ifdef COMPAT_FREEBSD32 1411 case BIOCGDLTLIST32: 1412 { 1413 struct bpf_dltlist32 *list32; 1414 struct bpf_dltlist dltlist; 1415 1416 list32 = (struct bpf_dltlist32 *)addr; 1417 dltlist.bfl_len = list32->bfl_len; 1418 dltlist.bfl_list = PTRIN(list32->bfl_list); 1419 BPF_LOCK(); 1420 if (d->bd_bif == NULL) 1421 error = EINVAL; 1422 else { 1423 error = bpf_getdltlist(d, &dltlist); 1424 if (error == 0) 1425 list32->bfl_len = dltlist.bfl_len; 1426 } 1427 BPF_UNLOCK(); 1428 break; 1429 } 1430 #endif 1431 1432 case BIOCGDLTLIST: 1433 BPF_LOCK(); 1434 if (d->bd_bif == NULL) 1435 error = EINVAL; 1436 else 1437 error = bpf_getdltlist(d, (struct bpf_dltlist *)addr); 1438 BPF_UNLOCK(); 1439 break; 1440 1441 /* 1442 * Set data link type. 1443 */ 1444 case BIOCSDLT: 1445 BPF_LOCK(); 1446 if (d->bd_bif == NULL) 1447 error = EINVAL; 1448 else 1449 error = bpf_setdlt(d, *(u_int *)addr); 1450 BPF_UNLOCK(); 1451 break; 1452 1453 /* 1454 * Get interface name. 1455 */ 1456 case BIOCGETIF: 1457 BPF_LOCK(); 1458 if (d->bd_bif == NULL) 1459 error = EINVAL; 1460 else { 1461 struct ifnet *const ifp = d->bd_bif->bif_ifp; 1462 struct ifreq *const ifr = (struct ifreq *)addr; 1463 1464 strlcpy(ifr->ifr_name, ifp->if_xname, 1465 sizeof(ifr->ifr_name)); 1466 } 1467 BPF_UNLOCK(); 1468 break; 1469 1470 /* 1471 * Set interface. 1472 */ 1473 case BIOCSETIF: 1474 BPF_LOCK(); 1475 error = bpf_setif(d, (struct ifreq *)addr); 1476 BPF_UNLOCK(); 1477 break; 1478 1479 /* 1480 * Set read timeout. 1481 */ 1482 case BIOCSRTIMEOUT: 1483 #if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1484 case BIOCSRTIMEOUT32: 1485 #endif 1486 { 1487 struct timeval *tv = (struct timeval *)addr; 1488 #if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1489 struct timeval32 *tv32; 1490 struct timeval tv64; 1491 1492 if (cmd == BIOCSRTIMEOUT32) { 1493 tv32 = (struct timeval32 *)addr; 1494 tv = &tv64; 1495 tv->tv_sec = tv32->tv_sec; 1496 tv->tv_usec = tv32->tv_usec; 1497 } else 1498 #endif 1499 tv = (struct timeval *)addr; 1500 1501 /* 1502 * Subtract 1 tick from tvtohz() since this isn't 1503 * a one-shot timer. 1504 */ 1505 if ((error = itimerfix(tv)) == 0) 1506 d->bd_rtout = tvtohz(tv) - 1; 1507 break; 1508 } 1509 1510 /* 1511 * Get read timeout. 1512 */ 1513 case BIOCGRTIMEOUT: 1514 #if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1515 case BIOCGRTIMEOUT32: 1516 #endif 1517 { 1518 struct timeval *tv; 1519 #if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1520 struct timeval32 *tv32; 1521 struct timeval tv64; 1522 1523 if (cmd == BIOCGRTIMEOUT32) 1524 tv = &tv64; 1525 else 1526 #endif 1527 tv = (struct timeval *)addr; 1528 1529 tv->tv_sec = d->bd_rtout / hz; 1530 tv->tv_usec = (d->bd_rtout % hz) * tick; 1531 #if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1532 if (cmd == BIOCGRTIMEOUT32) { 1533 tv32 = (struct timeval32 *)addr; 1534 tv32->tv_sec = tv->tv_sec; 1535 tv32->tv_usec = tv->tv_usec; 1536 } 1537 #endif 1538 1539 break; 1540 } 1541 1542 /* 1543 * Get packet stats. 1544 */ 1545 case BIOCGSTATS: 1546 { 1547 struct bpf_stat *bs = (struct bpf_stat *)addr; 1548 1549 /* XXXCSJP overflow */ 1550 bs->bs_recv = d->bd_rcount; 1551 bs->bs_drop = d->bd_dcount; 1552 break; 1553 } 1554 1555 /* 1556 * Set immediate mode. 1557 */ 1558 case BIOCIMMEDIATE: 1559 BPFD_LOCK(d); 1560 d->bd_immediate = *(u_int *)addr; 1561 BPFD_UNLOCK(d); 1562 break; 1563 1564 case BIOCVERSION: 1565 { 1566 struct bpf_version *bv = (struct bpf_version *)addr; 1567 1568 bv->bv_major = BPF_MAJOR_VERSION; 1569 bv->bv_minor = BPF_MINOR_VERSION; 1570 break; 1571 } 1572 1573 /* 1574 * Get "header already complete" flag 1575 */ 1576 case BIOCGHDRCMPLT: 1577 BPFD_LOCK(d); 1578 *(u_int *)addr = d->bd_hdrcmplt; 1579 BPFD_UNLOCK(d); 1580 break; 1581 1582 /* 1583 * Set "header already complete" flag 1584 */ 1585 case BIOCSHDRCMPLT: 1586 BPFD_LOCK(d); 1587 d->bd_hdrcmplt = *(u_int *)addr ? 1 : 0; 1588 BPFD_UNLOCK(d); 1589 break; 1590 1591 /* 1592 * Get packet direction flag 1593 */ 1594 case BIOCGDIRECTION: 1595 BPFD_LOCK(d); 1596 *(u_int *)addr = d->bd_direction; 1597 BPFD_UNLOCK(d); 1598 break; 1599 1600 /* 1601 * Set packet direction flag 1602 */ 1603 case BIOCSDIRECTION: 1604 { 1605 u_int direction; 1606 1607 direction = *(u_int *)addr; 1608 switch (direction) { 1609 case BPF_D_IN: 1610 case BPF_D_INOUT: 1611 case BPF_D_OUT: 1612 BPFD_LOCK(d); 1613 d->bd_direction = direction; 1614 BPFD_UNLOCK(d); 1615 break; 1616 default: 1617 error = EINVAL; 1618 } 1619 } 1620 break; 1621 1622 /* 1623 * Get packet timestamp format and resolution. 1624 */ 1625 case BIOCGTSTAMP: 1626 BPFD_LOCK(d); 1627 *(u_int *)addr = d->bd_tstamp; 1628 BPFD_UNLOCK(d); 1629 break; 1630 1631 /* 1632 * Set packet timestamp format and resolution. 1633 */ 1634 case BIOCSTSTAMP: 1635 { 1636 u_int func; 1637 1638 func = *(u_int *)addr; 1639 if (BPF_T_VALID(func)) 1640 d->bd_tstamp = func; 1641 else 1642 error = EINVAL; 1643 } 1644 break; 1645 1646 case BIOCFEEDBACK: 1647 BPFD_LOCK(d); 1648 d->bd_feedback = *(u_int *)addr; 1649 BPFD_UNLOCK(d); 1650 break; 1651 1652 case BIOCLOCK: 1653 BPFD_LOCK(d); 1654 d->bd_locked = 1; 1655 BPFD_UNLOCK(d); 1656 break; 1657 1658 case FIONBIO: /* Non-blocking I/O */ 1659 break; 1660 1661 case FIOASYNC: /* Send signal on receive packets */ 1662 BPFD_LOCK(d); 1663 d->bd_async = *(int *)addr; 1664 BPFD_UNLOCK(d); 1665 break; 1666 1667 case FIOSETOWN: 1668 /* 1669 * XXX: Add some sort of locking here? 1670 * fsetown() can sleep. 1671 */ 1672 error = fsetown(*(int *)addr, &d->bd_sigio); 1673 break; 1674 1675 case FIOGETOWN: 1676 BPFD_LOCK(d); 1677 *(int *)addr = fgetown(&d->bd_sigio); 1678 BPFD_UNLOCK(d); 1679 break; 1680 1681 /* This is deprecated, FIOSETOWN should be used instead. */ 1682 case TIOCSPGRP: 1683 error = fsetown(-(*(int *)addr), &d->bd_sigio); 1684 break; 1685 1686 /* This is deprecated, FIOGETOWN should be used instead. */ 1687 case TIOCGPGRP: 1688 *(int *)addr = -fgetown(&d->bd_sigio); 1689 break; 1690 1691 case BIOCSRSIG: /* Set receive signal */ 1692 { 1693 u_int sig; 1694 1695 sig = *(u_int *)addr; 1696 1697 if (sig >= NSIG) 1698 error = EINVAL; 1699 else { 1700 BPFD_LOCK(d); 1701 d->bd_sig = sig; 1702 BPFD_UNLOCK(d); 1703 } 1704 break; 1705 } 1706 case BIOCGRSIG: 1707 BPFD_LOCK(d); 1708 *(u_int *)addr = d->bd_sig; 1709 BPFD_UNLOCK(d); 1710 break; 1711 1712 case BIOCGETBUFMODE: 1713 BPFD_LOCK(d); 1714 *(u_int *)addr = d->bd_bufmode; 1715 BPFD_UNLOCK(d); 1716 break; 1717 1718 case BIOCSETBUFMODE: 1719 /* 1720 * Allow the buffering mode to be changed as long as we 1721 * haven't yet committed to a particular mode. Our 1722 * definition of commitment, for now, is whether or not a 1723 * buffer has been allocated or an interface attached, since 1724 * that's the point where things get tricky. 1725 */ 1726 switch (*(u_int *)addr) { 1727 case BPF_BUFMODE_BUFFER: 1728 break; 1729 1730 case BPF_BUFMODE_ZBUF: 1731 if (bpf_zerocopy_enable) 1732 break; 1733 /* FALLSTHROUGH */ 1734 1735 default: 1736 CURVNET_RESTORE(); 1737 return (EINVAL); 1738 } 1739 1740 BPFD_LOCK(d); 1741 if (d->bd_sbuf != NULL || d->bd_hbuf != NULL || 1742 d->bd_fbuf != NULL || d->bd_bif != NULL) { 1743 BPFD_UNLOCK(d); 1744 CURVNET_RESTORE(); 1745 return (EBUSY); 1746 } 1747 d->bd_bufmode = *(u_int *)addr; 1748 BPFD_UNLOCK(d); 1749 break; 1750 1751 case BIOCGETZMAX: 1752 error = bpf_ioctl_getzmax(td, d, (size_t *)addr); 1753 break; 1754 1755 case BIOCSETZBUF: 1756 error = bpf_ioctl_setzbuf(td, d, (struct bpf_zbuf *)addr); 1757 break; 1758 1759 case BIOCROTZBUF: 1760 error = bpf_ioctl_rotzbuf(td, d, (struct bpf_zbuf *)addr); 1761 break; 1762 } 1763 CURVNET_RESTORE(); 1764 return (error); 1765 } 1766 1767 /* 1768 * Set d's packet filter program to fp. If this file already has a filter, 1769 * free it and replace it. Returns EINVAL for bogus requests. 1770 * 1771 * Note we need global lock here to serialize bpf_setf() and bpf_setif() calls 1772 * since reading d->bd_bif can't be protected by d or interface lock due to 1773 * lock order. 1774 * 1775 * Additionally, we have to acquire interface write lock due to bpf_mtap() uses 1776 * interface read lock to read all filers. 1777 * 1778 */ 1779 static int 1780 bpf_setf(struct bpf_d *d, struct bpf_program *fp, u_long cmd) 1781 { 1782 #ifdef COMPAT_FREEBSD32 1783 struct bpf_program fp_swab; 1784 struct bpf_program32 *fp32; 1785 #endif 1786 struct bpf_insn *fcode, *old; 1787 #ifdef BPF_JITTER 1788 bpf_jit_filter *jfunc, *ofunc; 1789 #endif 1790 size_t size; 1791 u_int flen; 1792 int need_upgrade; 1793 1794 #ifdef COMPAT_FREEBSD32 1795 switch (cmd) { 1796 case BIOCSETF32: 1797 case BIOCSETWF32: 1798 case BIOCSETFNR32: 1799 fp32 = (struct bpf_program32 *)fp; 1800 fp_swab.bf_len = fp32->bf_len; 1801 fp_swab.bf_insns = (struct bpf_insn *)(uintptr_t)fp32->bf_insns; 1802 fp = &fp_swab; 1803 switch (cmd) { 1804 case BIOCSETF32: 1805 cmd = BIOCSETF; 1806 break; 1807 case BIOCSETWF32: 1808 cmd = BIOCSETWF; 1809 break; 1810 } 1811 break; 1812 } 1813 #endif 1814 1815 fcode = NULL; 1816 #ifdef BPF_JITTER 1817 jfunc = ofunc = NULL; 1818 #endif 1819 need_upgrade = 0; 1820 1821 /* 1822 * Check new filter validness before acquiring any locks. 1823 * Allocate memory for new filter, if needed. 1824 */ 1825 flen = fp->bf_len; 1826 if (flen > bpf_maxinsns || (fp->bf_insns == NULL && flen != 0)) 1827 return (EINVAL); 1828 size = flen * sizeof(*fp->bf_insns); 1829 if (size > 0) { 1830 /* We're setting up new filter. Copy and check actual data. */ 1831 fcode = malloc(size, M_BPF, M_WAITOK); 1832 if (copyin(fp->bf_insns, fcode, size) != 0 || 1833 !bpf_validate(fcode, flen)) { 1834 free(fcode, M_BPF); 1835 return (EINVAL); 1836 } 1837 #ifdef BPF_JITTER 1838 /* Filter is copied inside fcode and is perfectly valid. */ 1839 jfunc = bpf_jitter(fcode, flen); 1840 #endif 1841 } 1842 1843 BPF_LOCK(); 1844 1845 /* 1846 * Set up new filter. 1847 * Protect filter change by interface lock. 1848 * Additionally, we are protected by global lock here. 1849 */ 1850 if (d->bd_bif != NULL) 1851 BPFIF_WLOCK(d->bd_bif); 1852 BPFD_LOCK(d); 1853 if (cmd == BIOCSETWF) { 1854 old = d->bd_wfilter; 1855 d->bd_wfilter = fcode; 1856 } else { 1857 old = d->bd_rfilter; 1858 d->bd_rfilter = fcode; 1859 #ifdef BPF_JITTER 1860 ofunc = d->bd_bfilter; 1861 d->bd_bfilter = jfunc; 1862 #endif 1863 if (cmd == BIOCSETF) 1864 reset_d(d); 1865 1866 need_upgrade = bpf_check_upgrade(cmd, d, fcode, flen); 1867 } 1868 BPFD_UNLOCK(d); 1869 if (d->bd_bif != NULL) 1870 BPFIF_WUNLOCK(d->bd_bif); 1871 if (old != NULL) 1872 free(old, M_BPF); 1873 #ifdef BPF_JITTER 1874 if (ofunc != NULL) 1875 bpf_destroy_jit_filter(ofunc); 1876 #endif 1877 1878 /* Move d to active readers list. */ 1879 if (need_upgrade != 0) 1880 bpf_upgraded(d); 1881 1882 BPF_UNLOCK(); 1883 return (0); 1884 } 1885 1886 /* 1887 * Detach a file from its current interface (if attached at all) and attach 1888 * to the interface indicated by the name stored in ifr. 1889 * Return an errno or 0. 1890 */ 1891 static int 1892 bpf_setif(struct bpf_d *d, struct ifreq *ifr) 1893 { 1894 struct bpf_if *bp; 1895 struct ifnet *theywant; 1896 1897 BPF_LOCK_ASSERT(); 1898 1899 theywant = ifunit(ifr->ifr_name); 1900 if (theywant == NULL || theywant->if_bpf == NULL) 1901 return (ENXIO); 1902 1903 bp = theywant->if_bpf; 1904 1905 /* Check if interface is not being detached from BPF */ 1906 BPFIF_RLOCK(bp); 1907 if (bp->flags & BPFIF_FLAG_DYING) { 1908 BPFIF_RUNLOCK(bp); 1909 return (ENXIO); 1910 } 1911 BPFIF_RUNLOCK(bp); 1912 1913 /* 1914 * Behavior here depends on the buffering model. If we're using 1915 * kernel memory buffers, then we can allocate them here. If we're 1916 * using zero-copy, then the user process must have registered 1917 * buffers by the time we get here. If not, return an error. 1918 */ 1919 switch (d->bd_bufmode) { 1920 case BPF_BUFMODE_BUFFER: 1921 case BPF_BUFMODE_ZBUF: 1922 if (d->bd_sbuf == NULL) 1923 return (EINVAL); 1924 break; 1925 1926 default: 1927 panic("bpf_setif: bufmode %d", d->bd_bufmode); 1928 } 1929 if (bp != d->bd_bif) 1930 bpf_attachd(d, bp); 1931 BPFD_LOCK(d); 1932 reset_d(d); 1933 BPFD_UNLOCK(d); 1934 return (0); 1935 } 1936 1937 /* 1938 * Support for select() and poll() system calls 1939 * 1940 * Return true iff the specific operation will not block indefinitely. 1941 * Otherwise, return false but make a note that a selwakeup() must be done. 1942 */ 1943 static int 1944 bpfpoll(struct cdev *dev, int events, struct thread *td) 1945 { 1946 struct bpf_d *d; 1947 int revents; 1948 1949 if (devfs_get_cdevpriv((void **)&d) != 0 || d->bd_bif == NULL) 1950 return (events & 1951 (POLLHUP|POLLIN|POLLRDNORM|POLLOUT|POLLWRNORM)); 1952 1953 /* 1954 * Refresh PID associated with this descriptor. 1955 */ 1956 revents = events & (POLLOUT | POLLWRNORM); 1957 BPFD_LOCK(d); 1958 BPF_PID_REFRESH(d, td); 1959 if (events & (POLLIN | POLLRDNORM)) { 1960 if (bpf_ready(d)) 1961 revents |= events & (POLLIN | POLLRDNORM); 1962 else { 1963 selrecord(td, &d->bd_sel); 1964 /* Start the read timeout if necessary. */ 1965 if (d->bd_rtout > 0 && d->bd_state == BPF_IDLE) { 1966 callout_reset(&d->bd_callout, d->bd_rtout, 1967 bpf_timed_out, d); 1968 d->bd_state = BPF_WAITING; 1969 } 1970 } 1971 } 1972 BPFD_UNLOCK(d); 1973 return (revents); 1974 } 1975 1976 /* 1977 * Support for kevent() system call. Register EVFILT_READ filters and 1978 * reject all others. 1979 */ 1980 int 1981 bpfkqfilter(struct cdev *dev, struct knote *kn) 1982 { 1983 struct bpf_d *d; 1984 1985 if (devfs_get_cdevpriv((void **)&d) != 0 || 1986 kn->kn_filter != EVFILT_READ) 1987 return (1); 1988 1989 /* 1990 * Refresh PID associated with this descriptor. 1991 */ 1992 BPFD_LOCK(d); 1993 BPF_PID_REFRESH_CUR(d); 1994 kn->kn_fop = &bpfread_filtops; 1995 kn->kn_hook = d; 1996 knlist_add(&d->bd_sel.si_note, kn, 1); 1997 BPFD_UNLOCK(d); 1998 1999 return (0); 2000 } 2001 2002 static void 2003 filt_bpfdetach(struct knote *kn) 2004 { 2005 struct bpf_d *d = (struct bpf_d *)kn->kn_hook; 2006 2007 knlist_remove(&d->bd_sel.si_note, kn, 0); 2008 } 2009 2010 static int 2011 filt_bpfread(struct knote *kn, long hint) 2012 { 2013 struct bpf_d *d = (struct bpf_d *)kn->kn_hook; 2014 int ready; 2015 2016 BPFD_LOCK_ASSERT(d); 2017 ready = bpf_ready(d); 2018 if (ready) { 2019 kn->kn_data = d->bd_slen; 2020 while (d->bd_hbuf_in_use) 2021 mtx_sleep(&d->bd_hbuf_in_use, &d->bd_lock, 2022 PRINET, "bd_hbuf", 0); 2023 if (d->bd_hbuf) 2024 kn->kn_data += d->bd_hlen; 2025 } else if (d->bd_rtout > 0 && d->bd_state == BPF_IDLE) { 2026 callout_reset(&d->bd_callout, d->bd_rtout, 2027 bpf_timed_out, d); 2028 d->bd_state = BPF_WAITING; 2029 } 2030 2031 return (ready); 2032 } 2033 2034 #define BPF_TSTAMP_NONE 0 2035 #define BPF_TSTAMP_FAST 1 2036 #define BPF_TSTAMP_NORMAL 2 2037 #define BPF_TSTAMP_EXTERN 3 2038 2039 static int 2040 bpf_ts_quality(int tstype) 2041 { 2042 2043 if (tstype == BPF_T_NONE) 2044 return (BPF_TSTAMP_NONE); 2045 if ((tstype & BPF_T_FAST) != 0) 2046 return (BPF_TSTAMP_FAST); 2047 2048 return (BPF_TSTAMP_NORMAL); 2049 } 2050 2051 static int 2052 bpf_gettime(struct bintime *bt, int tstype, struct mbuf *m) 2053 { 2054 struct m_tag *tag; 2055 int quality; 2056 2057 quality = bpf_ts_quality(tstype); 2058 if (quality == BPF_TSTAMP_NONE) 2059 return (quality); 2060 2061 if (m != NULL) { 2062 tag = m_tag_locate(m, MTAG_BPF, MTAG_BPF_TIMESTAMP, NULL); 2063 if (tag != NULL) { 2064 *bt = *(struct bintime *)(tag + 1); 2065 return (BPF_TSTAMP_EXTERN); 2066 } 2067 } 2068 if (quality == BPF_TSTAMP_NORMAL) 2069 binuptime(bt); 2070 else 2071 getbinuptime(bt); 2072 2073 return (quality); 2074 } 2075 2076 /* 2077 * Incoming linkage from device drivers. Process the packet pkt, of length 2078 * pktlen, which is stored in a contiguous buffer. The packet is parsed 2079 * by each process' filter, and if accepted, stashed into the corresponding 2080 * buffer. 2081 */ 2082 void 2083 bpf_tap(struct bpf_if *bp, u_char *pkt, u_int pktlen) 2084 { 2085 struct bintime bt; 2086 struct bpf_d *d; 2087 #ifdef BPF_JITTER 2088 bpf_jit_filter *bf; 2089 #endif 2090 u_int slen; 2091 int gottime; 2092 2093 gottime = BPF_TSTAMP_NONE; 2094 2095 BPFIF_RLOCK(bp); 2096 2097 LIST_FOREACH(d, &bp->bif_dlist, bd_next) { 2098 /* 2099 * We are not using any locks for d here because: 2100 * 1) any filter change is protected by interface 2101 * write lock 2102 * 2) destroying/detaching d is protected by interface 2103 * write lock, too 2104 */ 2105 2106 /* XXX: Do not protect counter for the sake of performance. */ 2107 ++d->bd_rcount; 2108 /* 2109 * NB: We dont call BPF_CHECK_DIRECTION() here since there is no 2110 * way for the caller to indiciate to us whether this packet 2111 * is inbound or outbound. In the bpf_mtap() routines, we use 2112 * the interface pointers on the mbuf to figure it out. 2113 */ 2114 #ifdef BPF_JITTER 2115 bf = bpf_jitter_enable != 0 ? d->bd_bfilter : NULL; 2116 if (bf != NULL) 2117 slen = (*(bf->func))(pkt, pktlen, pktlen); 2118 else 2119 #endif 2120 slen = bpf_filter(d->bd_rfilter, pkt, pktlen, pktlen); 2121 if (slen != 0) { 2122 /* 2123 * Filter matches. Let's to acquire write lock. 2124 */ 2125 BPFD_LOCK(d); 2126 2127 d->bd_fcount++; 2128 if (gottime < bpf_ts_quality(d->bd_tstamp)) 2129 gottime = bpf_gettime(&bt, d->bd_tstamp, NULL); 2130 #ifdef MAC 2131 if (mac_bpfdesc_check_receive(d, bp->bif_ifp) == 0) 2132 #endif 2133 catchpacket(d, pkt, pktlen, slen, 2134 bpf_append_bytes, &bt); 2135 BPFD_UNLOCK(d); 2136 } 2137 } 2138 BPFIF_RUNLOCK(bp); 2139 } 2140 2141 #define BPF_CHECK_DIRECTION(d, r, i) \ 2142 (((d)->bd_direction == BPF_D_IN && (r) != (i)) || \ 2143 ((d)->bd_direction == BPF_D_OUT && (r) == (i))) 2144 2145 /* 2146 * Incoming linkage from device drivers, when packet is in an mbuf chain. 2147 * Locking model is explained in bpf_tap(). 2148 */ 2149 void 2150 bpf_mtap(struct bpf_if *bp, struct mbuf *m) 2151 { 2152 struct bintime bt; 2153 struct bpf_d *d; 2154 #ifdef BPF_JITTER 2155 bpf_jit_filter *bf; 2156 #endif 2157 u_int pktlen, slen; 2158 int gottime; 2159 2160 /* Skip outgoing duplicate packets. */ 2161 if ((m->m_flags & M_PROMISC) != 0 && m->m_pkthdr.rcvif == NULL) { 2162 m->m_flags &= ~M_PROMISC; 2163 return; 2164 } 2165 2166 pktlen = m_length(m, NULL); 2167 gottime = BPF_TSTAMP_NONE; 2168 2169 BPFIF_RLOCK(bp); 2170 2171 LIST_FOREACH(d, &bp->bif_dlist, bd_next) { 2172 if (BPF_CHECK_DIRECTION(d, m->m_pkthdr.rcvif, bp->bif_ifp)) 2173 continue; 2174 ++d->bd_rcount; 2175 #ifdef BPF_JITTER 2176 bf = bpf_jitter_enable != 0 ? d->bd_bfilter : NULL; 2177 /* XXX We cannot handle multiple mbufs. */ 2178 if (bf != NULL && m->m_next == NULL) 2179 slen = (*(bf->func))(mtod(m, u_char *), pktlen, pktlen); 2180 else 2181 #endif 2182 slen = bpf_filter(d->bd_rfilter, (u_char *)m, pktlen, 0); 2183 if (slen != 0) { 2184 BPFD_LOCK(d); 2185 2186 d->bd_fcount++; 2187 if (gottime < bpf_ts_quality(d->bd_tstamp)) 2188 gottime = bpf_gettime(&bt, d->bd_tstamp, m); 2189 #ifdef MAC 2190 if (mac_bpfdesc_check_receive(d, bp->bif_ifp) == 0) 2191 #endif 2192 catchpacket(d, (u_char *)m, pktlen, slen, 2193 bpf_append_mbuf, &bt); 2194 BPFD_UNLOCK(d); 2195 } 2196 } 2197 BPFIF_RUNLOCK(bp); 2198 } 2199 2200 /* 2201 * Incoming linkage from device drivers, when packet is in 2202 * an mbuf chain and to be prepended by a contiguous header. 2203 */ 2204 void 2205 bpf_mtap2(struct bpf_if *bp, void *data, u_int dlen, struct mbuf *m) 2206 { 2207 struct bintime bt; 2208 struct mbuf mb; 2209 struct bpf_d *d; 2210 u_int pktlen, slen; 2211 int gottime; 2212 2213 /* Skip outgoing duplicate packets. */ 2214 if ((m->m_flags & M_PROMISC) != 0 && m->m_pkthdr.rcvif == NULL) { 2215 m->m_flags &= ~M_PROMISC; 2216 return; 2217 } 2218 2219 pktlen = m_length(m, NULL); 2220 /* 2221 * Craft on-stack mbuf suitable for passing to bpf_filter. 2222 * Note that we cut corners here; we only setup what's 2223 * absolutely needed--this mbuf should never go anywhere else. 2224 */ 2225 mb.m_next = m; 2226 mb.m_data = data; 2227 mb.m_len = dlen; 2228 pktlen += dlen; 2229 2230 gottime = BPF_TSTAMP_NONE; 2231 2232 BPFIF_RLOCK(bp); 2233 2234 LIST_FOREACH(d, &bp->bif_dlist, bd_next) { 2235 if (BPF_CHECK_DIRECTION(d, m->m_pkthdr.rcvif, bp->bif_ifp)) 2236 continue; 2237 ++d->bd_rcount; 2238 slen = bpf_filter(d->bd_rfilter, (u_char *)&mb, pktlen, 0); 2239 if (slen != 0) { 2240 BPFD_LOCK(d); 2241 2242 d->bd_fcount++; 2243 if (gottime < bpf_ts_quality(d->bd_tstamp)) 2244 gottime = bpf_gettime(&bt, d->bd_tstamp, m); 2245 #ifdef MAC 2246 if (mac_bpfdesc_check_receive(d, bp->bif_ifp) == 0) 2247 #endif 2248 catchpacket(d, (u_char *)&mb, pktlen, slen, 2249 bpf_append_mbuf, &bt); 2250 BPFD_UNLOCK(d); 2251 } 2252 } 2253 BPFIF_RUNLOCK(bp); 2254 } 2255 2256 #undef BPF_CHECK_DIRECTION 2257 2258 #undef BPF_TSTAMP_NONE 2259 #undef BPF_TSTAMP_FAST 2260 #undef BPF_TSTAMP_NORMAL 2261 #undef BPF_TSTAMP_EXTERN 2262 2263 static int 2264 bpf_hdrlen(struct bpf_d *d) 2265 { 2266 int hdrlen; 2267 2268 hdrlen = d->bd_bif->bif_hdrlen; 2269 #ifndef BURN_BRIDGES 2270 if (d->bd_tstamp == BPF_T_NONE || 2271 BPF_T_FORMAT(d->bd_tstamp) == BPF_T_MICROTIME) 2272 #ifdef COMPAT_FREEBSD32 2273 if (d->bd_compat32) 2274 hdrlen += SIZEOF_BPF_HDR(struct bpf_hdr32); 2275 else 2276 #endif 2277 hdrlen += SIZEOF_BPF_HDR(struct bpf_hdr); 2278 else 2279 #endif 2280 hdrlen += SIZEOF_BPF_HDR(struct bpf_xhdr); 2281 #ifdef COMPAT_FREEBSD32 2282 if (d->bd_compat32) 2283 hdrlen = BPF_WORDALIGN32(hdrlen); 2284 else 2285 #endif 2286 hdrlen = BPF_WORDALIGN(hdrlen); 2287 2288 return (hdrlen - d->bd_bif->bif_hdrlen); 2289 } 2290 2291 static void 2292 bpf_bintime2ts(struct bintime *bt, struct bpf_ts *ts, int tstype) 2293 { 2294 struct bintime bt2; 2295 struct timeval tsm; 2296 struct timespec tsn; 2297 2298 if ((tstype & BPF_T_MONOTONIC) == 0) { 2299 bt2 = *bt; 2300 bintime_add(&bt2, &boottimebin); 2301 bt = &bt2; 2302 } 2303 switch (BPF_T_FORMAT(tstype)) { 2304 case BPF_T_MICROTIME: 2305 bintime2timeval(bt, &tsm); 2306 ts->bt_sec = tsm.tv_sec; 2307 ts->bt_frac = tsm.tv_usec; 2308 break; 2309 case BPF_T_NANOTIME: 2310 bintime2timespec(bt, &tsn); 2311 ts->bt_sec = tsn.tv_sec; 2312 ts->bt_frac = tsn.tv_nsec; 2313 break; 2314 case BPF_T_BINTIME: 2315 ts->bt_sec = bt->sec; 2316 ts->bt_frac = bt->frac; 2317 break; 2318 } 2319 } 2320 2321 /* 2322 * Move the packet data from interface memory (pkt) into the 2323 * store buffer. "cpfn" is the routine called to do the actual data 2324 * transfer. bcopy is passed in to copy contiguous chunks, while 2325 * bpf_append_mbuf is passed in to copy mbuf chains. In the latter case, 2326 * pkt is really an mbuf. 2327 */ 2328 static void 2329 catchpacket(struct bpf_d *d, u_char *pkt, u_int pktlen, u_int snaplen, 2330 void (*cpfn)(struct bpf_d *, caddr_t, u_int, void *, u_int), 2331 struct bintime *bt) 2332 { 2333 struct bpf_xhdr hdr; 2334 #ifndef BURN_BRIDGES 2335 struct bpf_hdr hdr_old; 2336 #ifdef COMPAT_FREEBSD32 2337 struct bpf_hdr32 hdr32_old; 2338 #endif 2339 #endif 2340 int caplen, curlen, hdrlen, totlen; 2341 int do_wakeup = 0; 2342 int do_timestamp; 2343 int tstype; 2344 2345 BPFD_LOCK_ASSERT(d); 2346 2347 /* 2348 * Detect whether user space has released a buffer back to us, and if 2349 * so, move it from being a hold buffer to a free buffer. This may 2350 * not be the best place to do it (for example, we might only want to 2351 * run this check if we need the space), but for now it's a reliable 2352 * spot to do it. 2353 */ 2354 if (d->bd_fbuf == NULL && bpf_canfreebuf(d)) { 2355 while (d->bd_hbuf_in_use) 2356 mtx_sleep(&d->bd_hbuf_in_use, &d->bd_lock, 2357 PRINET, "bd_hbuf", 0); 2358 d->bd_fbuf = d->bd_hbuf; 2359 d->bd_hbuf = NULL; 2360 d->bd_hlen = 0; 2361 bpf_buf_reclaimed(d); 2362 } 2363 2364 /* 2365 * Figure out how many bytes to move. If the packet is 2366 * greater or equal to the snapshot length, transfer that 2367 * much. Otherwise, transfer the whole packet (unless 2368 * we hit the buffer size limit). 2369 */ 2370 hdrlen = bpf_hdrlen(d); 2371 totlen = hdrlen + min(snaplen, pktlen); 2372 if (totlen > d->bd_bufsize) 2373 totlen = d->bd_bufsize; 2374 2375 /* 2376 * Round up the end of the previous packet to the next longword. 2377 * 2378 * Drop the packet if there's no room and no hope of room 2379 * If the packet would overflow the storage buffer or the storage 2380 * buffer is considered immutable by the buffer model, try to rotate 2381 * the buffer and wakeup pending processes. 2382 */ 2383 #ifdef COMPAT_FREEBSD32 2384 if (d->bd_compat32) 2385 curlen = BPF_WORDALIGN32(d->bd_slen); 2386 else 2387 #endif 2388 curlen = BPF_WORDALIGN(d->bd_slen); 2389 if (curlen + totlen > d->bd_bufsize || !bpf_canwritebuf(d)) { 2390 if (d->bd_fbuf == NULL) { 2391 /* 2392 * There's no room in the store buffer, and no 2393 * prospect of room, so drop the packet. Notify the 2394 * buffer model. 2395 */ 2396 bpf_buffull(d); 2397 ++d->bd_dcount; 2398 return; 2399 } 2400 while (d->bd_hbuf_in_use) 2401 mtx_sleep(&d->bd_hbuf_in_use, &d->bd_lock, 2402 PRINET, "bd_hbuf", 0); 2403 ROTATE_BUFFERS(d); 2404 do_wakeup = 1; 2405 curlen = 0; 2406 } else if (d->bd_immediate || d->bd_state == BPF_TIMED_OUT) 2407 /* 2408 * Immediate mode is set, or the read timeout has already 2409 * expired during a select call. A packet arrived, so the 2410 * reader should be woken up. 2411 */ 2412 do_wakeup = 1; 2413 caplen = totlen - hdrlen; 2414 tstype = d->bd_tstamp; 2415 do_timestamp = tstype != BPF_T_NONE; 2416 #ifndef BURN_BRIDGES 2417 if (tstype == BPF_T_NONE || BPF_T_FORMAT(tstype) == BPF_T_MICROTIME) { 2418 struct bpf_ts ts; 2419 if (do_timestamp) 2420 bpf_bintime2ts(bt, &ts, tstype); 2421 #ifdef COMPAT_FREEBSD32 2422 if (d->bd_compat32) { 2423 bzero(&hdr32_old, sizeof(hdr32_old)); 2424 if (do_timestamp) { 2425 hdr32_old.bh_tstamp.tv_sec = ts.bt_sec; 2426 hdr32_old.bh_tstamp.tv_usec = ts.bt_frac; 2427 } 2428 hdr32_old.bh_datalen = pktlen; 2429 hdr32_old.bh_hdrlen = hdrlen; 2430 hdr32_old.bh_caplen = caplen; 2431 bpf_append_bytes(d, d->bd_sbuf, curlen, &hdr32_old, 2432 sizeof(hdr32_old)); 2433 goto copy; 2434 } 2435 #endif 2436 bzero(&hdr_old, sizeof(hdr_old)); 2437 if (do_timestamp) { 2438 hdr_old.bh_tstamp.tv_sec = ts.bt_sec; 2439 hdr_old.bh_tstamp.tv_usec = ts.bt_frac; 2440 } 2441 hdr_old.bh_datalen = pktlen; 2442 hdr_old.bh_hdrlen = hdrlen; 2443 hdr_old.bh_caplen = caplen; 2444 bpf_append_bytes(d, d->bd_sbuf, curlen, &hdr_old, 2445 sizeof(hdr_old)); 2446 goto copy; 2447 } 2448 #endif 2449 2450 /* 2451 * Append the bpf header. Note we append the actual header size, but 2452 * move forward the length of the header plus padding. 2453 */ 2454 bzero(&hdr, sizeof(hdr)); 2455 if (do_timestamp) 2456 bpf_bintime2ts(bt, &hdr.bh_tstamp, tstype); 2457 hdr.bh_datalen = pktlen; 2458 hdr.bh_hdrlen = hdrlen; 2459 hdr.bh_caplen = caplen; 2460 bpf_append_bytes(d, d->bd_sbuf, curlen, &hdr, sizeof(hdr)); 2461 2462 /* 2463 * Copy the packet data into the store buffer and update its length. 2464 */ 2465 #ifndef BURN_BRIDGES 2466 copy: 2467 #endif 2468 (*cpfn)(d, d->bd_sbuf, curlen + hdrlen, pkt, caplen); 2469 d->bd_slen = curlen + totlen; 2470 2471 if (do_wakeup) 2472 bpf_wakeup(d); 2473 } 2474 2475 /* 2476 * Free buffers currently in use by a descriptor. 2477 * Called on close. 2478 */ 2479 static void 2480 bpf_freed(struct bpf_d *d) 2481 { 2482 2483 /* 2484 * We don't need to lock out interrupts since this descriptor has 2485 * been detached from its interface and it yet hasn't been marked 2486 * free. 2487 */ 2488 bpf_free(d); 2489 if (d->bd_rfilter != NULL) { 2490 free((caddr_t)d->bd_rfilter, M_BPF); 2491 #ifdef BPF_JITTER 2492 if (d->bd_bfilter != NULL) 2493 bpf_destroy_jit_filter(d->bd_bfilter); 2494 #endif 2495 } 2496 if (d->bd_wfilter != NULL) 2497 free((caddr_t)d->bd_wfilter, M_BPF); 2498 mtx_destroy(&d->bd_lock); 2499 } 2500 2501 /* 2502 * Attach an interface to bpf. dlt is the link layer type; hdrlen is the 2503 * fixed size of the link header (variable length headers not yet supported). 2504 */ 2505 void 2506 bpfattach(struct ifnet *ifp, u_int dlt, u_int hdrlen) 2507 { 2508 2509 bpfattach2(ifp, dlt, hdrlen, &ifp->if_bpf); 2510 } 2511 2512 /* 2513 * Attach an interface to bpf. ifp is a pointer to the structure 2514 * defining the interface to be attached, dlt is the link layer type, 2515 * and hdrlen is the fixed size of the link header (variable length 2516 * headers are not yet supporrted). 2517 */ 2518 void 2519 bpfattach2(struct ifnet *ifp, u_int dlt, u_int hdrlen, struct bpf_if **driverp) 2520 { 2521 struct bpf_if *bp; 2522 2523 bp = malloc(sizeof(*bp), M_BPF, M_NOWAIT | M_ZERO); 2524 if (bp == NULL) 2525 panic("bpfattach"); 2526 2527 LIST_INIT(&bp->bif_dlist); 2528 LIST_INIT(&bp->bif_wlist); 2529 bp->bif_ifp = ifp; 2530 bp->bif_dlt = dlt; 2531 rw_init(&bp->bif_lock, "bpf interface lock"); 2532 KASSERT(*driverp == NULL, ("bpfattach2: driverp already initialized")); 2533 *driverp = bp; 2534 2535 BPF_LOCK(); 2536 LIST_INSERT_HEAD(&bpf_iflist, bp, bif_next); 2537 BPF_UNLOCK(); 2538 2539 bp->bif_hdrlen = hdrlen; 2540 2541 if (bootverbose) 2542 if_printf(ifp, "bpf attached\n"); 2543 } 2544 2545 /* 2546 * Detach bpf from an interface. This involves detaching each descriptor 2547 * associated with the interface. Notify each descriptor as it's detached 2548 * so that any sleepers wake up and get ENXIO. 2549 */ 2550 void 2551 bpfdetach(struct ifnet *ifp) 2552 { 2553 struct bpf_if *bp, *bp_temp; 2554 struct bpf_d *d; 2555 int ndetached; 2556 2557 ndetached = 0; 2558 2559 BPF_LOCK(); 2560 /* Find all bpf_if struct's which reference ifp and detach them. */ 2561 LIST_FOREACH_SAFE(bp, &bpf_iflist, bif_next, bp_temp) { 2562 if (ifp != bp->bif_ifp) 2563 continue; 2564 2565 LIST_REMOVE(bp, bif_next); 2566 /* Add to to-be-freed list */ 2567 LIST_INSERT_HEAD(&bpf_freelist, bp, bif_next); 2568 2569 ndetached++; 2570 /* 2571 * Delay freeing bp till interface is detached 2572 * and all routes through this interface are removed. 2573 * Mark bp as detached to restrict new consumers. 2574 */ 2575 BPFIF_WLOCK(bp); 2576 bp->flags |= BPFIF_FLAG_DYING; 2577 BPFIF_WUNLOCK(bp); 2578 2579 CTR4(KTR_NET, "%s: sheduling free for encap %d (%p) for if %p", 2580 __func__, bp->bif_dlt, bp, ifp); 2581 2582 /* Free common descriptors */ 2583 while ((d = LIST_FIRST(&bp->bif_dlist)) != NULL) { 2584 bpf_detachd_locked(d); 2585 BPFD_LOCK(d); 2586 bpf_wakeup(d); 2587 BPFD_UNLOCK(d); 2588 } 2589 2590 /* Free writer-only descriptors */ 2591 while ((d = LIST_FIRST(&bp->bif_wlist)) != NULL) { 2592 bpf_detachd_locked(d); 2593 BPFD_LOCK(d); 2594 bpf_wakeup(d); 2595 BPFD_UNLOCK(d); 2596 } 2597 } 2598 BPF_UNLOCK(); 2599 2600 #ifdef INVARIANTS 2601 if (ndetached == 0) 2602 printf("bpfdetach: %s was not attached\n", ifp->if_xname); 2603 #endif 2604 } 2605 2606 /* 2607 * Interface departure handler. 2608 * Note departure event does not guarantee interface is going down. 2609 * Interface renaming is currently done via departure/arrival event set. 2610 * 2611 * Departure handled is called after all routes pointing to 2612 * given interface are removed and interface is in down state 2613 * restricting any packets to be sent/received. We assume it is now safe 2614 * to free data allocated by BPF. 2615 */ 2616 static void 2617 bpf_ifdetach(void *arg __unused, struct ifnet *ifp) 2618 { 2619 struct bpf_if *bp, *bp_temp; 2620 int nmatched = 0; 2621 2622 BPF_LOCK(); 2623 /* 2624 * Find matching entries in free list. 2625 * Nothing should be found if bpfdetach() was not called. 2626 */ 2627 LIST_FOREACH_SAFE(bp, &bpf_freelist, bif_next, bp_temp) { 2628 if (ifp != bp->bif_ifp) 2629 continue; 2630 2631 CTR3(KTR_NET, "%s: freeing BPF instance %p for interface %p", 2632 __func__, bp, ifp); 2633 2634 LIST_REMOVE(bp, bif_next); 2635 2636 rw_destroy(&bp->bif_lock); 2637 free(bp, M_BPF); 2638 2639 nmatched++; 2640 } 2641 BPF_UNLOCK(); 2642 2643 /* 2644 * Note that we cannot zero other pointers to 2645 * custom DLTs possibly used by given interface. 2646 */ 2647 if (nmatched != 0) 2648 ifp->if_bpf = NULL; 2649 } 2650 2651 /* 2652 * Get a list of available data link type of the interface. 2653 */ 2654 static int 2655 bpf_getdltlist(struct bpf_d *d, struct bpf_dltlist *bfl) 2656 { 2657 int n, error; 2658 struct ifnet *ifp; 2659 struct bpf_if *bp; 2660 2661 BPF_LOCK_ASSERT(); 2662 2663 ifp = d->bd_bif->bif_ifp; 2664 n = 0; 2665 error = 0; 2666 LIST_FOREACH(bp, &bpf_iflist, bif_next) { 2667 if (bp->bif_ifp != ifp) 2668 continue; 2669 if (bfl->bfl_list != NULL) { 2670 if (n >= bfl->bfl_len) 2671 return (ENOMEM); 2672 error = copyout(&bp->bif_dlt, 2673 bfl->bfl_list + n, sizeof(u_int)); 2674 } 2675 n++; 2676 } 2677 bfl->bfl_len = n; 2678 return (error); 2679 } 2680 2681 /* 2682 * Set the data link type of a BPF instance. 2683 */ 2684 static int 2685 bpf_setdlt(struct bpf_d *d, u_int dlt) 2686 { 2687 int error, opromisc; 2688 struct ifnet *ifp; 2689 struct bpf_if *bp; 2690 2691 BPF_LOCK_ASSERT(); 2692 2693 if (d->bd_bif->bif_dlt == dlt) 2694 return (0); 2695 ifp = d->bd_bif->bif_ifp; 2696 2697 LIST_FOREACH(bp, &bpf_iflist, bif_next) { 2698 if (bp->bif_ifp == ifp && bp->bif_dlt == dlt) 2699 break; 2700 } 2701 2702 if (bp != NULL) { 2703 opromisc = d->bd_promisc; 2704 bpf_attachd(d, bp); 2705 BPFD_LOCK(d); 2706 reset_d(d); 2707 BPFD_UNLOCK(d); 2708 if (opromisc) { 2709 error = ifpromisc(bp->bif_ifp, 1); 2710 if (error) 2711 if_printf(bp->bif_ifp, 2712 "bpf_setdlt: ifpromisc failed (%d)\n", 2713 error); 2714 else 2715 d->bd_promisc = 1; 2716 } 2717 } 2718 return (bp == NULL ? EINVAL : 0); 2719 } 2720 2721 static void 2722 bpf_drvinit(void *unused) 2723 { 2724 struct cdev *dev; 2725 2726 mtx_init(&bpf_mtx, "bpf global lock", NULL, MTX_DEF); 2727 LIST_INIT(&bpf_iflist); 2728 LIST_INIT(&bpf_freelist); 2729 2730 dev = make_dev(&bpf_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, "bpf"); 2731 /* For compatibility */ 2732 make_dev_alias(dev, "bpf0"); 2733 2734 /* Register interface departure handler */ 2735 bpf_ifdetach_cookie = EVENTHANDLER_REGISTER( 2736 ifnet_departure_event, bpf_ifdetach, NULL, 2737 EVENTHANDLER_PRI_ANY); 2738 } 2739 2740 /* 2741 * Zero out the various packet counters associated with all of the bpf 2742 * descriptors. At some point, we will probably want to get a bit more 2743 * granular and allow the user to specify descriptors to be zeroed. 2744 */ 2745 static void 2746 bpf_zero_counters(void) 2747 { 2748 struct bpf_if *bp; 2749 struct bpf_d *bd; 2750 2751 BPF_LOCK(); 2752 LIST_FOREACH(bp, &bpf_iflist, bif_next) { 2753 BPFIF_RLOCK(bp); 2754 LIST_FOREACH(bd, &bp->bif_dlist, bd_next) { 2755 BPFD_LOCK(bd); 2756 bd->bd_rcount = 0; 2757 bd->bd_dcount = 0; 2758 bd->bd_fcount = 0; 2759 bd->bd_wcount = 0; 2760 bd->bd_wfcount = 0; 2761 bd->bd_zcopy = 0; 2762 BPFD_UNLOCK(bd); 2763 } 2764 BPFIF_RUNLOCK(bp); 2765 } 2766 BPF_UNLOCK(); 2767 } 2768 2769 /* 2770 * Fill filter statistics 2771 */ 2772 static void 2773 bpfstats_fill_xbpf(struct xbpf_d *d, struct bpf_d *bd) 2774 { 2775 2776 bzero(d, sizeof(*d)); 2777 BPFD_LOCK_ASSERT(bd); 2778 d->bd_structsize = sizeof(*d); 2779 /* XXX: reading should be protected by global lock */ 2780 d->bd_immediate = bd->bd_immediate; 2781 d->bd_promisc = bd->bd_promisc; 2782 d->bd_hdrcmplt = bd->bd_hdrcmplt; 2783 d->bd_direction = bd->bd_direction; 2784 d->bd_feedback = bd->bd_feedback; 2785 d->bd_async = bd->bd_async; 2786 d->bd_rcount = bd->bd_rcount; 2787 d->bd_dcount = bd->bd_dcount; 2788 d->bd_fcount = bd->bd_fcount; 2789 d->bd_sig = bd->bd_sig; 2790 d->bd_slen = bd->bd_slen; 2791 d->bd_hlen = bd->bd_hlen; 2792 d->bd_bufsize = bd->bd_bufsize; 2793 d->bd_pid = bd->bd_pid; 2794 strlcpy(d->bd_ifname, 2795 bd->bd_bif->bif_ifp->if_xname, IFNAMSIZ); 2796 d->bd_locked = bd->bd_locked; 2797 d->bd_wcount = bd->bd_wcount; 2798 d->bd_wdcount = bd->bd_wdcount; 2799 d->bd_wfcount = bd->bd_wfcount; 2800 d->bd_zcopy = bd->bd_zcopy; 2801 d->bd_bufmode = bd->bd_bufmode; 2802 } 2803 2804 /* 2805 * Handle `netstat -B' stats request 2806 */ 2807 static int 2808 bpf_stats_sysctl(SYSCTL_HANDLER_ARGS) 2809 { 2810 static const struct xbpf_d zerostats; 2811 struct xbpf_d *xbdbuf, *xbd, tempstats; 2812 int index, error; 2813 struct bpf_if *bp; 2814 struct bpf_d *bd; 2815 2816 /* 2817 * XXX This is not technically correct. It is possible for non 2818 * privileged users to open bpf devices. It would make sense 2819 * if the users who opened the devices were able to retrieve 2820 * the statistics for them, too. 2821 */ 2822 error = priv_check(req->td, PRIV_NET_BPF); 2823 if (error) 2824 return (error); 2825 /* 2826 * Check to see if the user is requesting that the counters be 2827 * zeroed out. Explicitly check that the supplied data is zeroed, 2828 * as we aren't allowing the user to set the counters currently. 2829 */ 2830 if (req->newptr != NULL) { 2831 if (req->newlen != sizeof(tempstats)) 2832 return (EINVAL); 2833 memset(&tempstats, 0, sizeof(tempstats)); 2834 error = SYSCTL_IN(req, &tempstats, sizeof(tempstats)); 2835 if (error) 2836 return (error); 2837 if (bcmp(&tempstats, &zerostats, sizeof(tempstats)) != 0) 2838 return (EINVAL); 2839 bpf_zero_counters(); 2840 return (0); 2841 } 2842 if (req->oldptr == NULL) 2843 return (SYSCTL_OUT(req, 0, bpf_bpfd_cnt * sizeof(*xbd))); 2844 if (bpf_bpfd_cnt == 0) 2845 return (SYSCTL_OUT(req, 0, 0)); 2846 xbdbuf = malloc(req->oldlen, M_BPF, M_WAITOK); 2847 BPF_LOCK(); 2848 if (req->oldlen < (bpf_bpfd_cnt * sizeof(*xbd))) { 2849 BPF_UNLOCK(); 2850 free(xbdbuf, M_BPF); 2851 return (ENOMEM); 2852 } 2853 index = 0; 2854 LIST_FOREACH(bp, &bpf_iflist, bif_next) { 2855 BPFIF_RLOCK(bp); 2856 /* Send writers-only first */ 2857 LIST_FOREACH(bd, &bp->bif_wlist, bd_next) { 2858 xbd = &xbdbuf[index++]; 2859 BPFD_LOCK(bd); 2860 bpfstats_fill_xbpf(xbd, bd); 2861 BPFD_UNLOCK(bd); 2862 } 2863 LIST_FOREACH(bd, &bp->bif_dlist, bd_next) { 2864 xbd = &xbdbuf[index++]; 2865 BPFD_LOCK(bd); 2866 bpfstats_fill_xbpf(xbd, bd); 2867 BPFD_UNLOCK(bd); 2868 } 2869 BPFIF_RUNLOCK(bp); 2870 } 2871 BPF_UNLOCK(); 2872 error = SYSCTL_OUT(req, xbdbuf, index * sizeof(*xbd)); 2873 free(xbdbuf, M_BPF); 2874 return (error); 2875 } 2876 2877 SYSINIT(bpfdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE,bpf_drvinit,NULL); 2878 2879 #else /* !DEV_BPF && !NETGRAPH_BPF */ 2880 /* 2881 * NOP stubs to allow bpf-using drivers to load and function. 2882 * 2883 * A 'better' implementation would allow the core bpf functionality 2884 * to be loaded at runtime. 2885 */ 2886 static struct bpf_if bp_null; 2887 2888 void 2889 bpf_tap(struct bpf_if *bp, u_char *pkt, u_int pktlen) 2890 { 2891 } 2892 2893 void 2894 bpf_mtap(struct bpf_if *bp, struct mbuf *m) 2895 { 2896 } 2897 2898 void 2899 bpf_mtap2(struct bpf_if *bp, void *d, u_int l, struct mbuf *m) 2900 { 2901 } 2902 2903 void 2904 bpfattach(struct ifnet *ifp, u_int dlt, u_int hdrlen) 2905 { 2906 2907 bpfattach2(ifp, dlt, hdrlen, &ifp->if_bpf); 2908 } 2909 2910 void 2911 bpfattach2(struct ifnet *ifp, u_int dlt, u_int hdrlen, struct bpf_if **driverp) 2912 { 2913 2914 *driverp = &bp_null; 2915 } 2916 2917 void 2918 bpfdetach(struct ifnet *ifp) 2919 { 2920 } 2921 2922 u_int 2923 bpf_filter(const struct bpf_insn *pc, u_char *p, u_int wirelen, u_int buflen) 2924 { 2925 return -1; /* "no filter" behaviour */ 2926 } 2927 2928 int 2929 bpf_validate(const struct bpf_insn *f, int len) 2930 { 2931 return 0; /* false */ 2932 } 2933 2934 #endif /* !DEV_BPF && !NETGRAPH_BPF */ 2935