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 #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 90 MALLOC_DEFINE(M_BPF, "BPF", "BPF data"); 91 92 struct bpf_if { 93 #define bif_next bif_ext.bif_next 94 #define bif_dlist bif_ext.bif_dlist 95 struct bpf_if_ext bif_ext; /* public members */ 96 u_int bif_dlt; /* link layer type */ 97 u_int bif_hdrlen; /* length of link header */ 98 struct ifnet *bif_ifp; /* corresponding interface */ 99 struct rwlock bif_lock; /* interface lock */ 100 LIST_HEAD(, bpf_d) bif_wlist; /* writer-only list */ 101 int bif_flags; /* Interface flags */ 102 }; 103 104 CTASSERT(offsetof(struct bpf_if, bif_ext) == 0); 105 106 #if defined(DEV_BPF) || defined(NETGRAPH_BPF) 107 108 #define PRINET 26 /* interruptible */ 109 110 #define SIZEOF_BPF_HDR(type) \ 111 (offsetof(type, bh_hdrlen) + sizeof(((type *)0)->bh_hdrlen)) 112 113 #ifdef COMPAT_FREEBSD32 114 #include <sys/mount.h> 115 #include <compat/freebsd32/freebsd32.h> 116 #define BPF_ALIGNMENT32 sizeof(int32_t) 117 #define BPF_WORDALIGN32(x) (((x)+(BPF_ALIGNMENT32-1))&~(BPF_ALIGNMENT32-1)) 118 119 #ifndef BURN_BRIDGES 120 /* 121 * 32-bit version of structure prepended to each packet. We use this header 122 * instead of the standard one for 32-bit streams. We mark the a stream as 123 * 32-bit the first time we see a 32-bit compat ioctl request. 124 */ 125 struct bpf_hdr32 { 126 struct timeval32 bh_tstamp; /* time stamp */ 127 uint32_t bh_caplen; /* length of captured portion */ 128 uint32_t bh_datalen; /* original length of packet */ 129 uint16_t bh_hdrlen; /* length of bpf header (this struct 130 plus alignment padding) */ 131 }; 132 #endif 133 134 struct bpf_program32 { 135 u_int bf_len; 136 uint32_t bf_insns; 137 }; 138 139 struct bpf_dltlist32 { 140 u_int bfl_len; 141 u_int bfl_list; 142 }; 143 144 #define BIOCSETF32 _IOW('B', 103, struct bpf_program32) 145 #define BIOCSRTIMEOUT32 _IOW('B', 109, struct timeval32) 146 #define BIOCGRTIMEOUT32 _IOR('B', 110, struct timeval32) 147 #define BIOCGDLTLIST32 _IOWR('B', 121, struct bpf_dltlist32) 148 #define BIOCSETWF32 _IOW('B', 123, struct bpf_program32) 149 #define BIOCSETFNR32 _IOW('B', 130, struct bpf_program32) 150 #endif 151 152 /* 153 * bpf_iflist is a list of BPF interface structures, each corresponding to a 154 * specific DLT. The same network interface might have several BPF interface 155 * structures registered by different layers in the stack (i.e., 802.11 156 * frames, ethernet frames, etc). 157 */ 158 static LIST_HEAD(, bpf_if) bpf_iflist, bpf_freelist; 159 static struct mtx bpf_mtx; /* bpf global lock */ 160 static int bpf_bpfd_cnt; 161 162 static void bpf_attachd(struct bpf_d *, struct bpf_if *); 163 static void bpf_detachd(struct bpf_d *); 164 static void bpf_detachd_locked(struct bpf_d *); 165 static void bpf_freed(struct bpf_d *); 166 static int bpf_movein(struct uio *, int, struct ifnet *, struct mbuf **, 167 struct sockaddr *, int *, struct bpf_insn *); 168 static int bpf_setif(struct bpf_d *, struct ifreq *); 169 static void bpf_timed_out(void *); 170 static __inline void 171 bpf_wakeup(struct bpf_d *); 172 static void catchpacket(struct bpf_d *, u_char *, u_int, u_int, 173 void (*)(struct bpf_d *, caddr_t, u_int, void *, u_int), 174 struct bintime *); 175 static void reset_d(struct bpf_d *); 176 static int bpf_setf(struct bpf_d *, struct bpf_program *, u_long cmd); 177 static int bpf_getdltlist(struct bpf_d *, struct bpf_dltlist *); 178 static int bpf_setdlt(struct bpf_d *, u_int); 179 static void filt_bpfdetach(struct knote *); 180 static int filt_bpfread(struct knote *, long); 181 static void bpf_drvinit(void *); 182 static int bpf_stats_sysctl(SYSCTL_HANDLER_ARGS); 183 184 SYSCTL_NODE(_net, OID_AUTO, bpf, CTLFLAG_RW, 0, "bpf sysctl"); 185 int bpf_maxinsns = BPF_MAXINSNS; 186 SYSCTL_INT(_net_bpf, OID_AUTO, maxinsns, CTLFLAG_RW, 187 &bpf_maxinsns, 0, "Maximum bpf program instructions"); 188 static int bpf_zerocopy_enable = 0; 189 SYSCTL_INT(_net_bpf, OID_AUTO, zerocopy_enable, CTLFLAG_RW, 190 &bpf_zerocopy_enable, 0, "Enable new zero-copy BPF buffer sessions"); 191 static SYSCTL_NODE(_net_bpf, OID_AUTO, stats, CTLFLAG_MPSAFE | CTLFLAG_RW, 192 bpf_stats_sysctl, "bpf statistics portal"); 193 194 static VNET_DEFINE(int, bpf_optimize_writers) = 0; 195 #define V_bpf_optimize_writers VNET(bpf_optimize_writers) 196 SYSCTL_INT(_net_bpf, OID_AUTO, optimize_writers, CTLFLAG_VNET | CTLFLAG_RW, 197 &VNET_NAME(bpf_optimize_writers), 0, 198 "Do not send packets until BPF program is set"); 199 200 static d_open_t bpfopen; 201 static d_read_t bpfread; 202 static d_write_t bpfwrite; 203 static d_ioctl_t bpfioctl; 204 static d_poll_t bpfpoll; 205 static d_kqfilter_t bpfkqfilter; 206 207 static struct cdevsw bpf_cdevsw = { 208 .d_version = D_VERSION, 209 .d_open = bpfopen, 210 .d_read = bpfread, 211 .d_write = bpfwrite, 212 .d_ioctl = bpfioctl, 213 .d_poll = bpfpoll, 214 .d_name = "bpf", 215 .d_kqfilter = bpfkqfilter, 216 }; 217 218 static struct filterops bpfread_filtops = { 219 .f_isfd = 1, 220 .f_detach = filt_bpfdetach, 221 .f_event = filt_bpfread, 222 }; 223 224 eventhandler_tag bpf_ifdetach_cookie = NULL; 225 226 /* 227 * LOCKING MODEL USED BY BPF: 228 * Locks: 229 * 1) global lock (BPF_LOCK). Mutex, used to protect interface addition/removal, 230 * some global counters and every bpf_if reference. 231 * 2) Interface lock. Rwlock, used to protect list of BPF descriptors and their filters. 232 * 3) Descriptor lock. Mutex, used to protect BPF buffers and various structure fields 233 * used by bpf_mtap code. 234 * 235 * Lock order: 236 * 237 * Global lock, interface lock, descriptor lock 238 * 239 * We have to acquire interface lock before descriptor main lock due to BPF_MTAP[2] 240 * working model. In many places (like bpf_detachd) we start with BPF descriptor 241 * (and we need to at least rlock it to get reliable interface pointer). This 242 * gives us potential LOR. As a result, we use global lock to protect from bpf_if 243 * change in every such place. 244 * 245 * Changing d->bd_bif is protected by 1) global lock, 2) interface lock and 246 * 3) descriptor main wlock. 247 * Reading bd_bif can be protected by any of these locks, typically global lock. 248 * 249 * Changing read/write BPF filter is protected by the same three locks, 250 * the same applies for reading. 251 * 252 * Sleeping in global lock is not allowed due to bpfdetach() using it. 253 */ 254 255 /* 256 * Wrapper functions for various buffering methods. If the set of buffer 257 * modes expands, we will probably want to introduce a switch data structure 258 * similar to protosw, et. 259 */ 260 static void 261 bpf_append_bytes(struct bpf_d *d, caddr_t buf, u_int offset, void *src, 262 u_int len) 263 { 264 265 BPFD_LOCK_ASSERT(d); 266 267 switch (d->bd_bufmode) { 268 case BPF_BUFMODE_BUFFER: 269 return (bpf_buffer_append_bytes(d, buf, offset, src, len)); 270 271 case BPF_BUFMODE_ZBUF: 272 d->bd_zcopy++; 273 return (bpf_zerocopy_append_bytes(d, buf, offset, src, len)); 274 275 default: 276 panic("bpf_buf_append_bytes"); 277 } 278 } 279 280 static void 281 bpf_append_mbuf(struct bpf_d *d, caddr_t buf, u_int offset, void *src, 282 u_int len) 283 { 284 285 BPFD_LOCK_ASSERT(d); 286 287 switch (d->bd_bufmode) { 288 case BPF_BUFMODE_BUFFER: 289 return (bpf_buffer_append_mbuf(d, buf, offset, src, len)); 290 291 case BPF_BUFMODE_ZBUF: 292 d->bd_zcopy++; 293 return (bpf_zerocopy_append_mbuf(d, buf, offset, src, len)); 294 295 default: 296 panic("bpf_buf_append_mbuf"); 297 } 298 } 299 300 /* 301 * This function gets called when the free buffer is re-assigned. 302 */ 303 static void 304 bpf_buf_reclaimed(struct bpf_d *d) 305 { 306 307 BPFD_LOCK_ASSERT(d); 308 309 switch (d->bd_bufmode) { 310 case BPF_BUFMODE_BUFFER: 311 return; 312 313 case BPF_BUFMODE_ZBUF: 314 bpf_zerocopy_buf_reclaimed(d); 315 return; 316 317 default: 318 panic("bpf_buf_reclaimed"); 319 } 320 } 321 322 /* 323 * If the buffer mechanism has a way to decide that a held buffer can be made 324 * free, then it is exposed via the bpf_canfreebuf() interface. (1) is 325 * returned if the buffer can be discarded, (0) is returned if it cannot. 326 */ 327 static int 328 bpf_canfreebuf(struct bpf_d *d) 329 { 330 331 BPFD_LOCK_ASSERT(d); 332 333 switch (d->bd_bufmode) { 334 case BPF_BUFMODE_ZBUF: 335 return (bpf_zerocopy_canfreebuf(d)); 336 } 337 return (0); 338 } 339 340 /* 341 * Allow the buffer model to indicate that the current store buffer is 342 * immutable, regardless of the appearance of space. Return (1) if the 343 * buffer is writable, and (0) if not. 344 */ 345 static int 346 bpf_canwritebuf(struct bpf_d *d) 347 { 348 BPFD_LOCK_ASSERT(d); 349 350 switch (d->bd_bufmode) { 351 case BPF_BUFMODE_ZBUF: 352 return (bpf_zerocopy_canwritebuf(d)); 353 } 354 return (1); 355 } 356 357 /* 358 * Notify buffer model that an attempt to write to the store buffer has 359 * resulted in a dropped packet, in which case the buffer may be considered 360 * full. 361 */ 362 static void 363 bpf_buffull(struct bpf_d *d) 364 { 365 366 BPFD_LOCK_ASSERT(d); 367 368 switch (d->bd_bufmode) { 369 case BPF_BUFMODE_ZBUF: 370 bpf_zerocopy_buffull(d); 371 break; 372 } 373 } 374 375 /* 376 * Notify the buffer model that a buffer has moved into the hold position. 377 */ 378 void 379 bpf_bufheld(struct bpf_d *d) 380 { 381 382 BPFD_LOCK_ASSERT(d); 383 384 switch (d->bd_bufmode) { 385 case BPF_BUFMODE_ZBUF: 386 bpf_zerocopy_bufheld(d); 387 break; 388 } 389 } 390 391 static void 392 bpf_free(struct bpf_d *d) 393 { 394 395 switch (d->bd_bufmode) { 396 case BPF_BUFMODE_BUFFER: 397 return (bpf_buffer_free(d)); 398 399 case BPF_BUFMODE_ZBUF: 400 return (bpf_zerocopy_free(d)); 401 402 default: 403 panic("bpf_buf_free"); 404 } 405 } 406 407 static int 408 bpf_uiomove(struct bpf_d *d, caddr_t buf, u_int len, struct uio *uio) 409 { 410 411 if (d->bd_bufmode != BPF_BUFMODE_BUFFER) 412 return (EOPNOTSUPP); 413 return (bpf_buffer_uiomove(d, buf, len, uio)); 414 } 415 416 static int 417 bpf_ioctl_sblen(struct bpf_d *d, u_int *i) 418 { 419 420 if (d->bd_bufmode != BPF_BUFMODE_BUFFER) 421 return (EOPNOTSUPP); 422 return (bpf_buffer_ioctl_sblen(d, i)); 423 } 424 425 static int 426 bpf_ioctl_getzmax(struct thread *td, struct bpf_d *d, size_t *i) 427 { 428 429 if (d->bd_bufmode != BPF_BUFMODE_ZBUF) 430 return (EOPNOTSUPP); 431 return (bpf_zerocopy_ioctl_getzmax(td, d, i)); 432 } 433 434 static int 435 bpf_ioctl_rotzbuf(struct thread *td, struct bpf_d *d, struct bpf_zbuf *bz) 436 { 437 438 if (d->bd_bufmode != BPF_BUFMODE_ZBUF) 439 return (EOPNOTSUPP); 440 return (bpf_zerocopy_ioctl_rotzbuf(td, d, bz)); 441 } 442 443 static int 444 bpf_ioctl_setzbuf(struct thread *td, struct bpf_d *d, struct bpf_zbuf *bz) 445 { 446 447 if (d->bd_bufmode != BPF_BUFMODE_ZBUF) 448 return (EOPNOTSUPP); 449 return (bpf_zerocopy_ioctl_setzbuf(td, d, bz)); 450 } 451 452 /* 453 * General BPF functions. 454 */ 455 static int 456 bpf_movein(struct uio *uio, int linktype, struct ifnet *ifp, struct mbuf **mp, 457 struct sockaddr *sockp, int *hdrlen, struct bpf_insn *wfilter) 458 { 459 const struct ieee80211_bpf_params *p; 460 struct ether_header *eh; 461 struct mbuf *m; 462 int error; 463 int len; 464 int hlen; 465 int slen; 466 467 /* 468 * Build a sockaddr based on the data link layer type. 469 * We do this at this level because the ethernet header 470 * is copied directly into the data field of the sockaddr. 471 * In the case of SLIP, there is no header and the packet 472 * is forwarded as is. 473 * Also, we are careful to leave room at the front of the mbuf 474 * for the link level header. 475 */ 476 switch (linktype) { 477 478 case DLT_SLIP: 479 sockp->sa_family = AF_INET; 480 hlen = 0; 481 break; 482 483 case DLT_EN10MB: 484 sockp->sa_family = AF_UNSPEC; 485 /* XXX Would MAXLINKHDR be better? */ 486 hlen = ETHER_HDR_LEN; 487 break; 488 489 case DLT_FDDI: 490 sockp->sa_family = AF_IMPLINK; 491 hlen = 0; 492 break; 493 494 case DLT_RAW: 495 sockp->sa_family = AF_UNSPEC; 496 hlen = 0; 497 break; 498 499 case DLT_NULL: 500 /* 501 * null interface types require a 4 byte pseudo header which 502 * corresponds to the address family of the packet. 503 */ 504 sockp->sa_family = AF_UNSPEC; 505 hlen = 4; 506 break; 507 508 case DLT_ATM_RFC1483: 509 /* 510 * en atm driver requires 4-byte atm pseudo header. 511 * though it isn't standard, vpi:vci needs to be 512 * specified anyway. 513 */ 514 sockp->sa_family = AF_UNSPEC; 515 hlen = 12; /* XXX 4(ATM_PH) + 3(LLC) + 5(SNAP) */ 516 break; 517 518 case DLT_PPP: 519 sockp->sa_family = AF_UNSPEC; 520 hlen = 4; /* This should match PPP_HDRLEN */ 521 break; 522 523 case DLT_IEEE802_11: /* IEEE 802.11 wireless */ 524 sockp->sa_family = AF_IEEE80211; 525 hlen = 0; 526 break; 527 528 case DLT_IEEE802_11_RADIO: /* IEEE 802.11 wireless w/ phy params */ 529 sockp->sa_family = AF_IEEE80211; 530 sockp->sa_len = 12; /* XXX != 0 */ 531 hlen = sizeof(struct ieee80211_bpf_params); 532 break; 533 534 default: 535 return (EIO); 536 } 537 538 len = uio->uio_resid; 539 if (len < hlen || len - hlen > ifp->if_mtu) 540 return (EMSGSIZE); 541 542 m = m_get2(len, M_WAITOK, MT_DATA, M_PKTHDR); 543 if (m == NULL) 544 return (EIO); 545 m->m_pkthdr.len = m->m_len = len; 546 *mp = m; 547 548 error = uiomove(mtod(m, u_char *), len, uio); 549 if (error) 550 goto bad; 551 552 slen = bpf_filter(wfilter, mtod(m, u_char *), len, len); 553 if (slen == 0) { 554 error = EPERM; 555 goto bad; 556 } 557 558 /* Check for multicast destination */ 559 switch (linktype) { 560 case DLT_EN10MB: 561 eh = mtod(m, struct ether_header *); 562 if (ETHER_IS_MULTICAST(eh->ether_dhost)) { 563 if (bcmp(ifp->if_broadcastaddr, eh->ether_dhost, 564 ETHER_ADDR_LEN) == 0) 565 m->m_flags |= M_BCAST; 566 else 567 m->m_flags |= M_MCAST; 568 } 569 break; 570 } 571 572 /* 573 * Make room for link header, and copy it to sockaddr 574 */ 575 if (hlen != 0) { 576 if (sockp->sa_family == AF_IEEE80211) { 577 /* 578 * Collect true length from the parameter header 579 * NB: sockp is known to be zero'd so if we do a 580 * short copy unspecified parameters will be 581 * zero. 582 * NB: packet may not be aligned after stripping 583 * bpf params 584 * XXX check ibp_vers 585 */ 586 p = mtod(m, const struct ieee80211_bpf_params *); 587 hlen = p->ibp_len; 588 if (hlen > sizeof(sockp->sa_data)) { 589 error = EINVAL; 590 goto bad; 591 } 592 } 593 bcopy(mtod(m, const void *), sockp->sa_data, hlen); 594 } 595 *hdrlen = hlen; 596 597 return (0); 598 bad: 599 m_freem(m); 600 return (error); 601 } 602 603 /* 604 * Attach file to the bpf interface, i.e. make d listen on bp. 605 */ 606 static void 607 bpf_attachd(struct bpf_d *d, struct bpf_if *bp) 608 { 609 int op_w; 610 611 BPF_LOCK_ASSERT(); 612 613 /* 614 * Save sysctl value to protect from sysctl change 615 * between reads 616 */ 617 op_w = V_bpf_optimize_writers || d->bd_writer; 618 619 if (d->bd_bif != NULL) 620 bpf_detachd_locked(d); 621 /* 622 * Point d at bp, and add d to the interface's list. 623 * Since there are many applications using BPF for 624 * sending raw packets only (dhcpd, cdpd are good examples) 625 * we can delay adding d to the list of active listeners until 626 * some filter is configured. 627 */ 628 629 BPFIF_WLOCK(bp); 630 BPFD_LOCK(d); 631 632 d->bd_bif = bp; 633 634 if (op_w != 0) { 635 /* Add to writers-only list */ 636 LIST_INSERT_HEAD(&bp->bif_wlist, d, bd_next); 637 /* 638 * We decrement bd_writer on every filter set operation. 639 * First BIOCSETF is done by pcap_open_live() to set up 640 * snap length. After that appliation usually sets its own filter 641 */ 642 d->bd_writer = 2; 643 } else 644 LIST_INSERT_HEAD(&bp->bif_dlist, d, bd_next); 645 646 BPFD_UNLOCK(d); 647 BPFIF_WUNLOCK(bp); 648 649 bpf_bpfd_cnt++; 650 651 CTR3(KTR_NET, "%s: bpf_attach called by pid %d, adding to %s list", 652 __func__, d->bd_pid, d->bd_writer ? "writer" : "active"); 653 654 if (op_w == 0) 655 EVENTHANDLER_INVOKE(bpf_track, bp->bif_ifp, bp->bif_dlt, 1); 656 } 657 658 /* 659 * Check if we need to upgrade our descriptor @d from write-only mode. 660 */ 661 static int 662 bpf_check_upgrade(u_long cmd, struct bpf_d *d, struct bpf_insn *fcode, int flen) 663 { 664 int is_snap, need_upgrade; 665 666 /* 667 * Check if we've already upgraded or new filter is empty. 668 */ 669 if (d->bd_writer == 0 || fcode == NULL) 670 return (0); 671 672 need_upgrade = 0; 673 674 /* 675 * Check if cmd looks like snaplen setting from 676 * pcap_bpf.c:pcap_open_live(). 677 * Note we're not checking .k value here: 678 * while pcap_open_live() definitely sets to to non-zero value, 679 * we'd prefer to treat k=0 (deny ALL) case the same way: e.g. 680 * do not consider upgrading immediately 681 */ 682 if (cmd == BIOCSETF && flen == 1 && fcode[0].code == (BPF_RET | BPF_K)) 683 is_snap = 1; 684 else 685 is_snap = 0; 686 687 if (is_snap == 0) { 688 /* 689 * We're setting first filter and it doesn't look like 690 * setting snaplen. We're probably using bpf directly. 691 * Upgrade immediately. 692 */ 693 need_upgrade = 1; 694 } else { 695 /* 696 * Do not require upgrade by first BIOCSETF 697 * (used to set snaplen) by pcap_open_live(). 698 */ 699 700 if (--d->bd_writer == 0) { 701 /* 702 * First snaplen filter has already 703 * been set. This is probably catch-all 704 * filter 705 */ 706 need_upgrade = 1; 707 } 708 } 709 710 CTR5(KTR_NET, 711 "%s: filter function set by pid %d, " 712 "bd_writer counter %d, snap %d upgrade %d", 713 __func__, d->bd_pid, d->bd_writer, 714 is_snap, need_upgrade); 715 716 return (need_upgrade); 717 } 718 719 /* 720 * Add d to the list of active bp filters. 721 * Requires bpf_attachd() to be called before. 722 */ 723 static void 724 bpf_upgraded(struct bpf_d *d) 725 { 726 struct bpf_if *bp; 727 728 BPF_LOCK_ASSERT(); 729 730 bp = d->bd_bif; 731 732 /* 733 * Filter can be set several times without specifying interface. 734 * Mark d as reader and exit. 735 */ 736 if (bp == NULL) { 737 BPFD_LOCK(d); 738 d->bd_writer = 0; 739 BPFD_UNLOCK(d); 740 return; 741 } 742 743 BPFIF_WLOCK(bp); 744 BPFD_LOCK(d); 745 746 /* Remove from writers-only list */ 747 LIST_REMOVE(d, bd_next); 748 LIST_INSERT_HEAD(&bp->bif_dlist, d, bd_next); 749 /* Mark d as reader */ 750 d->bd_writer = 0; 751 752 BPFD_UNLOCK(d); 753 BPFIF_WUNLOCK(bp); 754 755 CTR2(KTR_NET, "%s: upgrade required by pid %d", __func__, d->bd_pid); 756 757 EVENTHANDLER_INVOKE(bpf_track, bp->bif_ifp, bp->bif_dlt, 1); 758 } 759 760 /* 761 * Detach a file from its interface. 762 */ 763 static void 764 bpf_detachd(struct bpf_d *d) 765 { 766 BPF_LOCK(); 767 bpf_detachd_locked(d); 768 BPF_UNLOCK(); 769 } 770 771 static void 772 bpf_detachd_locked(struct bpf_d *d) 773 { 774 int error; 775 struct bpf_if *bp; 776 struct ifnet *ifp; 777 778 CTR2(KTR_NET, "%s: detach required by pid %d", __func__, d->bd_pid); 779 780 BPF_LOCK_ASSERT(); 781 782 /* Check if descriptor is attached */ 783 if ((bp = d->bd_bif) == NULL) 784 return; 785 786 BPFIF_WLOCK(bp); 787 BPFD_LOCK(d); 788 789 /* Save bd_writer value */ 790 error = d->bd_writer; 791 792 /* 793 * Remove d from the interface's descriptor list. 794 */ 795 LIST_REMOVE(d, bd_next); 796 797 ifp = bp->bif_ifp; 798 d->bd_bif = NULL; 799 BPFD_UNLOCK(d); 800 BPFIF_WUNLOCK(bp); 801 802 bpf_bpfd_cnt--; 803 804 /* Call event handler iff d is attached */ 805 if (error == 0) 806 EVENTHANDLER_INVOKE(bpf_track, ifp, bp->bif_dlt, 0); 807 808 /* 809 * Check if this descriptor had requested promiscuous mode. 810 * If so, turn it off. 811 */ 812 if (d->bd_promisc) { 813 d->bd_promisc = 0; 814 CURVNET_SET(ifp->if_vnet); 815 error = ifpromisc(ifp, 0); 816 CURVNET_RESTORE(); 817 if (error != 0 && error != ENXIO) { 818 /* 819 * ENXIO can happen if a pccard is unplugged 820 * Something is really wrong if we were able to put 821 * the driver into promiscuous mode, but can't 822 * take it out. 823 */ 824 if_printf(bp->bif_ifp, 825 "bpf_detach: ifpromisc failed (%d)\n", error); 826 } 827 } 828 } 829 830 /* 831 * Close the descriptor by detaching it from its interface, 832 * deallocating its buffers, and marking it free. 833 */ 834 static void 835 bpf_dtor(void *data) 836 { 837 struct bpf_d *d = data; 838 839 BPFD_LOCK(d); 840 if (d->bd_state == BPF_WAITING) 841 callout_stop(&d->bd_callout); 842 d->bd_state = BPF_IDLE; 843 BPFD_UNLOCK(d); 844 funsetown(&d->bd_sigio); 845 bpf_detachd(d); 846 #ifdef MAC 847 mac_bpfdesc_destroy(d); 848 #endif /* MAC */ 849 seldrain(&d->bd_sel); 850 knlist_destroy(&d->bd_sel.si_note); 851 callout_drain(&d->bd_callout); 852 bpf_freed(d); 853 free(d, M_BPF); 854 } 855 856 /* 857 * Open ethernet device. Returns ENXIO for illegal minor device number, 858 * EBUSY if file is open by another process. 859 */ 860 /* ARGSUSED */ 861 static int 862 bpfopen(struct cdev *dev, int flags, int fmt, struct thread *td) 863 { 864 struct bpf_d *d; 865 int error; 866 867 d = malloc(sizeof(*d), M_BPF, M_WAITOK | M_ZERO); 868 error = devfs_set_cdevpriv(d, bpf_dtor); 869 if (error != 0) { 870 free(d, M_BPF); 871 return (error); 872 } 873 874 /* 875 * For historical reasons, perform a one-time initialization call to 876 * the buffer routines, even though we're not yet committed to a 877 * particular buffer method. 878 */ 879 bpf_buffer_init(d); 880 if ((flags & FREAD) == 0) 881 d->bd_writer = 2; 882 d->bd_hbuf_in_use = 0; 883 d->bd_bufmode = BPF_BUFMODE_BUFFER; 884 d->bd_sig = SIGIO; 885 d->bd_direction = BPF_D_INOUT; 886 BPF_PID_REFRESH(d, td); 887 #ifdef MAC 888 mac_bpfdesc_init(d); 889 mac_bpfdesc_create(td->td_ucred, d); 890 #endif 891 mtx_init(&d->bd_lock, devtoname(dev), "bpf cdev lock", MTX_DEF); 892 callout_init_mtx(&d->bd_callout, &d->bd_lock, 0); 893 knlist_init_mtx(&d->bd_sel.si_note, &d->bd_lock); 894 895 return (0); 896 } 897 898 /* 899 * bpfread - read next chunk of packets from buffers 900 */ 901 static int 902 bpfread(struct cdev *dev, struct uio *uio, int ioflag) 903 { 904 struct bpf_d *d; 905 int error; 906 int non_block; 907 int timed_out; 908 909 error = devfs_get_cdevpriv((void **)&d); 910 if (error != 0) 911 return (error); 912 913 /* 914 * Restrict application to use a buffer the same size as 915 * as kernel buffers. 916 */ 917 if (uio->uio_resid != d->bd_bufsize) 918 return (EINVAL); 919 920 non_block = ((ioflag & O_NONBLOCK) != 0); 921 922 BPFD_LOCK(d); 923 BPF_PID_REFRESH_CUR(d); 924 if (d->bd_bufmode != BPF_BUFMODE_BUFFER) { 925 BPFD_UNLOCK(d); 926 return (EOPNOTSUPP); 927 } 928 if (d->bd_state == BPF_WAITING) 929 callout_stop(&d->bd_callout); 930 timed_out = (d->bd_state == BPF_TIMED_OUT); 931 d->bd_state = BPF_IDLE; 932 while (d->bd_hbuf_in_use) { 933 error = mtx_sleep(&d->bd_hbuf_in_use, &d->bd_lock, 934 PRINET|PCATCH, "bd_hbuf", 0); 935 if (error != 0) { 936 BPFD_UNLOCK(d); 937 return (error); 938 } 939 } 940 /* 941 * If the hold buffer is empty, then do a timed sleep, which 942 * ends when the timeout expires or when enough packets 943 * have arrived to fill the store buffer. 944 */ 945 while (d->bd_hbuf == NULL) { 946 if (d->bd_slen != 0) { 947 /* 948 * A packet(s) either arrived since the previous 949 * read or arrived while we were asleep. 950 */ 951 if (d->bd_immediate || non_block || timed_out) { 952 /* 953 * Rotate the buffers and return what's here 954 * if we are in immediate mode, non-blocking 955 * flag is set, or this descriptor timed out. 956 */ 957 ROTATE_BUFFERS(d); 958 break; 959 } 960 } 961 962 /* 963 * No data is available, check to see if the bpf device 964 * is still pointed at a real interface. If not, return 965 * ENXIO so that the userland process knows to rebind 966 * it before using it again. 967 */ 968 if (d->bd_bif == NULL) { 969 BPFD_UNLOCK(d); 970 return (ENXIO); 971 } 972 973 if (non_block) { 974 BPFD_UNLOCK(d); 975 return (EWOULDBLOCK); 976 } 977 error = msleep(d, &d->bd_lock, PRINET|PCATCH, 978 "bpf", d->bd_rtout); 979 if (error == EINTR || error == ERESTART) { 980 BPFD_UNLOCK(d); 981 return (error); 982 } 983 if (error == EWOULDBLOCK) { 984 /* 985 * On a timeout, return what's in the buffer, 986 * which may be nothing. If there is something 987 * in the store buffer, we can rotate the buffers. 988 */ 989 if (d->bd_hbuf) 990 /* 991 * We filled up the buffer in between 992 * getting the timeout and arriving 993 * here, so we don't need to rotate. 994 */ 995 break; 996 997 if (d->bd_slen == 0) { 998 BPFD_UNLOCK(d); 999 return (0); 1000 } 1001 ROTATE_BUFFERS(d); 1002 break; 1003 } 1004 } 1005 /* 1006 * At this point, we know we have something in the hold slot. 1007 */ 1008 d->bd_hbuf_in_use = 1; 1009 BPFD_UNLOCK(d); 1010 1011 /* 1012 * Move data from hold buffer into user space. 1013 * We know the entire buffer is transferred since 1014 * we checked above that the read buffer is bpf_bufsize bytes. 1015 * 1016 * We do not have to worry about simultaneous reads because 1017 * we waited for sole access to the hold buffer above. 1018 */ 1019 error = bpf_uiomove(d, d->bd_hbuf, d->bd_hlen, uio); 1020 1021 BPFD_LOCK(d); 1022 KASSERT(d->bd_hbuf != NULL, ("bpfread: lost bd_hbuf")); 1023 d->bd_fbuf = d->bd_hbuf; 1024 d->bd_hbuf = NULL; 1025 d->bd_hlen = 0; 1026 bpf_buf_reclaimed(d); 1027 d->bd_hbuf_in_use = 0; 1028 wakeup(&d->bd_hbuf_in_use); 1029 BPFD_UNLOCK(d); 1030 1031 return (error); 1032 } 1033 1034 /* 1035 * If there are processes sleeping on this descriptor, wake them up. 1036 */ 1037 static __inline void 1038 bpf_wakeup(struct bpf_d *d) 1039 { 1040 1041 BPFD_LOCK_ASSERT(d); 1042 if (d->bd_state == BPF_WAITING) { 1043 callout_stop(&d->bd_callout); 1044 d->bd_state = BPF_IDLE; 1045 } 1046 wakeup(d); 1047 if (d->bd_async && d->bd_sig && d->bd_sigio) 1048 pgsigio(&d->bd_sigio, d->bd_sig, 0); 1049 1050 selwakeuppri(&d->bd_sel, PRINET); 1051 KNOTE_LOCKED(&d->bd_sel.si_note, 0); 1052 } 1053 1054 static void 1055 bpf_timed_out(void *arg) 1056 { 1057 struct bpf_d *d = (struct bpf_d *)arg; 1058 1059 BPFD_LOCK_ASSERT(d); 1060 1061 if (callout_pending(&d->bd_callout) || !callout_active(&d->bd_callout)) 1062 return; 1063 if (d->bd_state == BPF_WAITING) { 1064 d->bd_state = BPF_TIMED_OUT; 1065 if (d->bd_slen != 0) 1066 bpf_wakeup(d); 1067 } 1068 } 1069 1070 static int 1071 bpf_ready(struct bpf_d *d) 1072 { 1073 1074 BPFD_LOCK_ASSERT(d); 1075 1076 if (!bpf_canfreebuf(d) && d->bd_hlen != 0) 1077 return (1); 1078 if ((d->bd_immediate || d->bd_state == BPF_TIMED_OUT) && 1079 d->bd_slen != 0) 1080 return (1); 1081 return (0); 1082 } 1083 1084 static int 1085 bpfwrite(struct cdev *dev, struct uio *uio, int ioflag) 1086 { 1087 struct bpf_d *d; 1088 struct ifnet *ifp; 1089 struct mbuf *m, *mc; 1090 struct sockaddr dst; 1091 int error, hlen; 1092 1093 error = devfs_get_cdevpriv((void **)&d); 1094 if (error != 0) 1095 return (error); 1096 1097 BPF_PID_REFRESH_CUR(d); 1098 d->bd_wcount++; 1099 /* XXX: locking required */ 1100 if (d->bd_bif == NULL) { 1101 d->bd_wdcount++; 1102 return (ENXIO); 1103 } 1104 1105 ifp = d->bd_bif->bif_ifp; 1106 1107 if ((ifp->if_flags & IFF_UP) == 0) { 1108 d->bd_wdcount++; 1109 return (ENETDOWN); 1110 } 1111 1112 if (uio->uio_resid == 0) { 1113 d->bd_wdcount++; 1114 return (0); 1115 } 1116 1117 bzero(&dst, sizeof(dst)); 1118 m = NULL; 1119 hlen = 0; 1120 /* XXX: bpf_movein() can sleep */ 1121 error = bpf_movein(uio, (int)d->bd_bif->bif_dlt, ifp, 1122 &m, &dst, &hlen, d->bd_wfilter); 1123 if (error) { 1124 d->bd_wdcount++; 1125 return (error); 1126 } 1127 d->bd_wfcount++; 1128 if (d->bd_hdrcmplt) 1129 dst.sa_family = pseudo_AF_HDRCMPLT; 1130 1131 if (d->bd_feedback) { 1132 mc = m_dup(m, M_NOWAIT); 1133 if (mc != NULL) 1134 mc->m_pkthdr.rcvif = ifp; 1135 /* Set M_PROMISC for outgoing packets to be discarded. */ 1136 if (d->bd_direction == BPF_D_INOUT) 1137 m->m_flags |= M_PROMISC; 1138 } else 1139 mc = NULL; 1140 1141 m->m_pkthdr.len -= hlen; 1142 m->m_len -= hlen; 1143 m->m_data += hlen; /* XXX */ 1144 1145 CURVNET_SET(ifp->if_vnet); 1146 #ifdef MAC 1147 BPFD_LOCK(d); 1148 mac_bpfdesc_create_mbuf(d, m); 1149 if (mc != NULL) 1150 mac_bpfdesc_create_mbuf(d, mc); 1151 BPFD_UNLOCK(d); 1152 #endif 1153 1154 error = (*ifp->if_output)(ifp, m, &dst, NULL); 1155 if (error) 1156 d->bd_wdcount++; 1157 1158 if (mc != NULL) { 1159 if (error == 0) 1160 (*ifp->if_input)(ifp, mc); 1161 else 1162 m_freem(mc); 1163 } 1164 CURVNET_RESTORE(); 1165 1166 return (error); 1167 } 1168 1169 /* 1170 * Reset a descriptor by flushing its packet buffer and clearing the receive 1171 * and drop counts. This is doable for kernel-only buffers, but with 1172 * zero-copy buffers, we can't write to (or rotate) buffers that are 1173 * currently owned by userspace. It would be nice if we could encapsulate 1174 * this logic in the buffer code rather than here. 1175 */ 1176 static void 1177 reset_d(struct bpf_d *d) 1178 { 1179 1180 BPFD_LOCK_ASSERT(d); 1181 1182 while (d->bd_hbuf_in_use) 1183 mtx_sleep(&d->bd_hbuf_in_use, &d->bd_lock, PRINET, 1184 "bd_hbuf", 0); 1185 if ((d->bd_hbuf != NULL) && 1186 (d->bd_bufmode != BPF_BUFMODE_ZBUF || bpf_canfreebuf(d))) { 1187 /* Free the hold buffer. */ 1188 d->bd_fbuf = d->bd_hbuf; 1189 d->bd_hbuf = NULL; 1190 d->bd_hlen = 0; 1191 bpf_buf_reclaimed(d); 1192 } 1193 if (bpf_canwritebuf(d)) 1194 d->bd_slen = 0; 1195 d->bd_rcount = 0; 1196 d->bd_dcount = 0; 1197 d->bd_fcount = 0; 1198 d->bd_wcount = 0; 1199 d->bd_wfcount = 0; 1200 d->bd_wdcount = 0; 1201 d->bd_zcopy = 0; 1202 } 1203 1204 /* 1205 * FIONREAD Check for read packet available. 1206 * BIOCGBLEN Get buffer len [for read()]. 1207 * BIOCSETF Set read filter. 1208 * BIOCSETFNR Set read filter without resetting descriptor. 1209 * BIOCSETWF Set write filter. 1210 * BIOCFLUSH Flush read packet buffer. 1211 * BIOCPROMISC Put interface into promiscuous mode. 1212 * BIOCGDLT Get link layer type. 1213 * BIOCGETIF Get interface name. 1214 * BIOCSETIF Set interface. 1215 * BIOCSRTIMEOUT Set read timeout. 1216 * BIOCGRTIMEOUT Get read timeout. 1217 * BIOCGSTATS Get packet stats. 1218 * BIOCIMMEDIATE Set immediate mode. 1219 * BIOCVERSION Get filter language version. 1220 * BIOCGHDRCMPLT Get "header already complete" flag 1221 * BIOCSHDRCMPLT Set "header already complete" flag 1222 * BIOCGDIRECTION Get packet direction flag 1223 * BIOCSDIRECTION Set packet direction flag 1224 * BIOCGTSTAMP Get time stamp format and resolution. 1225 * BIOCSTSTAMP Set time stamp format and resolution. 1226 * BIOCLOCK Set "locked" flag 1227 * BIOCFEEDBACK Set packet feedback mode. 1228 * BIOCSETZBUF Set current zero-copy buffer locations. 1229 * BIOCGETZMAX Get maximum zero-copy buffer size. 1230 * BIOCROTZBUF Force rotation of zero-copy buffer 1231 * BIOCSETBUFMODE Set buffer mode. 1232 * BIOCGETBUFMODE Get current buffer mode. 1233 */ 1234 /* ARGSUSED */ 1235 static int 1236 bpfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags, 1237 struct thread *td) 1238 { 1239 struct bpf_d *d; 1240 int error; 1241 1242 error = devfs_get_cdevpriv((void **)&d); 1243 if (error != 0) 1244 return (error); 1245 1246 /* 1247 * Refresh PID associated with this descriptor. 1248 */ 1249 BPFD_LOCK(d); 1250 BPF_PID_REFRESH(d, td); 1251 if (d->bd_state == BPF_WAITING) 1252 callout_stop(&d->bd_callout); 1253 d->bd_state = BPF_IDLE; 1254 BPFD_UNLOCK(d); 1255 1256 if (d->bd_locked == 1) { 1257 switch (cmd) { 1258 case BIOCGBLEN: 1259 case BIOCFLUSH: 1260 case BIOCGDLT: 1261 case BIOCGDLTLIST: 1262 #ifdef COMPAT_FREEBSD32 1263 case BIOCGDLTLIST32: 1264 #endif 1265 case BIOCGETIF: 1266 case BIOCGRTIMEOUT: 1267 #if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1268 case BIOCGRTIMEOUT32: 1269 #endif 1270 case BIOCGSTATS: 1271 case BIOCVERSION: 1272 case BIOCGRSIG: 1273 case BIOCGHDRCMPLT: 1274 case BIOCSTSTAMP: 1275 case BIOCFEEDBACK: 1276 case FIONREAD: 1277 case BIOCLOCK: 1278 case BIOCSRTIMEOUT: 1279 #if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1280 case BIOCSRTIMEOUT32: 1281 #endif 1282 case BIOCIMMEDIATE: 1283 case TIOCGPGRP: 1284 case BIOCROTZBUF: 1285 break; 1286 default: 1287 return (EPERM); 1288 } 1289 } 1290 #ifdef COMPAT_FREEBSD32 1291 /* 1292 * If we see a 32-bit compat ioctl, mark the stream as 32-bit so 1293 * that it will get 32-bit packet headers. 1294 */ 1295 switch (cmd) { 1296 case BIOCSETF32: 1297 case BIOCSETFNR32: 1298 case BIOCSETWF32: 1299 case BIOCGDLTLIST32: 1300 case BIOCGRTIMEOUT32: 1301 case BIOCSRTIMEOUT32: 1302 BPFD_LOCK(d); 1303 d->bd_compat32 = 1; 1304 BPFD_UNLOCK(d); 1305 } 1306 #endif 1307 1308 CURVNET_SET(TD_TO_VNET(td)); 1309 switch (cmd) { 1310 1311 default: 1312 error = EINVAL; 1313 break; 1314 1315 /* 1316 * Check for read packet available. 1317 */ 1318 case FIONREAD: 1319 { 1320 int n; 1321 1322 BPFD_LOCK(d); 1323 n = d->bd_slen; 1324 while (d->bd_hbuf_in_use) 1325 mtx_sleep(&d->bd_hbuf_in_use, &d->bd_lock, 1326 PRINET, "bd_hbuf", 0); 1327 if (d->bd_hbuf) 1328 n += d->bd_hlen; 1329 BPFD_UNLOCK(d); 1330 1331 *(int *)addr = n; 1332 break; 1333 } 1334 1335 /* 1336 * Get buffer len [for read()]. 1337 */ 1338 case BIOCGBLEN: 1339 BPFD_LOCK(d); 1340 *(u_int *)addr = d->bd_bufsize; 1341 BPFD_UNLOCK(d); 1342 break; 1343 1344 /* 1345 * Set buffer length. 1346 */ 1347 case BIOCSBLEN: 1348 error = bpf_ioctl_sblen(d, (u_int *)addr); 1349 break; 1350 1351 /* 1352 * Set link layer read filter. 1353 */ 1354 case BIOCSETF: 1355 case BIOCSETFNR: 1356 case BIOCSETWF: 1357 #ifdef COMPAT_FREEBSD32 1358 case BIOCSETF32: 1359 case BIOCSETFNR32: 1360 case BIOCSETWF32: 1361 #endif 1362 error = bpf_setf(d, (struct bpf_program *)addr, cmd); 1363 break; 1364 1365 /* 1366 * Flush read packet buffer. 1367 */ 1368 case BIOCFLUSH: 1369 BPFD_LOCK(d); 1370 reset_d(d); 1371 BPFD_UNLOCK(d); 1372 break; 1373 1374 /* 1375 * Put interface into promiscuous mode. 1376 */ 1377 case BIOCPROMISC: 1378 if (d->bd_bif == NULL) { 1379 /* 1380 * No interface attached yet. 1381 */ 1382 error = EINVAL; 1383 break; 1384 } 1385 if (d->bd_promisc == 0) { 1386 error = ifpromisc(d->bd_bif->bif_ifp, 1); 1387 if (error == 0) 1388 d->bd_promisc = 1; 1389 } 1390 break; 1391 1392 /* 1393 * Get current data link type. 1394 */ 1395 case BIOCGDLT: 1396 BPF_LOCK(); 1397 if (d->bd_bif == NULL) 1398 error = EINVAL; 1399 else 1400 *(u_int *)addr = d->bd_bif->bif_dlt; 1401 BPF_UNLOCK(); 1402 break; 1403 1404 /* 1405 * Get a list of supported data link types. 1406 */ 1407 #ifdef COMPAT_FREEBSD32 1408 case BIOCGDLTLIST32: 1409 { 1410 struct bpf_dltlist32 *list32; 1411 struct bpf_dltlist dltlist; 1412 1413 list32 = (struct bpf_dltlist32 *)addr; 1414 dltlist.bfl_len = list32->bfl_len; 1415 dltlist.bfl_list = PTRIN(list32->bfl_list); 1416 BPF_LOCK(); 1417 if (d->bd_bif == NULL) 1418 error = EINVAL; 1419 else { 1420 error = bpf_getdltlist(d, &dltlist); 1421 if (error == 0) 1422 list32->bfl_len = dltlist.bfl_len; 1423 } 1424 BPF_UNLOCK(); 1425 break; 1426 } 1427 #endif 1428 1429 case BIOCGDLTLIST: 1430 BPF_LOCK(); 1431 if (d->bd_bif == NULL) 1432 error = EINVAL; 1433 else 1434 error = bpf_getdltlist(d, (struct bpf_dltlist *)addr); 1435 BPF_UNLOCK(); 1436 break; 1437 1438 /* 1439 * Set data link type. 1440 */ 1441 case BIOCSDLT: 1442 BPF_LOCK(); 1443 if (d->bd_bif == NULL) 1444 error = EINVAL; 1445 else 1446 error = bpf_setdlt(d, *(u_int *)addr); 1447 BPF_UNLOCK(); 1448 break; 1449 1450 /* 1451 * Get interface name. 1452 */ 1453 case BIOCGETIF: 1454 BPF_LOCK(); 1455 if (d->bd_bif == NULL) 1456 error = EINVAL; 1457 else { 1458 struct ifnet *const ifp = d->bd_bif->bif_ifp; 1459 struct ifreq *const ifr = (struct ifreq *)addr; 1460 1461 strlcpy(ifr->ifr_name, ifp->if_xname, 1462 sizeof(ifr->ifr_name)); 1463 } 1464 BPF_UNLOCK(); 1465 break; 1466 1467 /* 1468 * Set interface. 1469 */ 1470 case BIOCSETIF: 1471 { 1472 int alloc_buf, size; 1473 1474 /* 1475 * Behavior here depends on the buffering model. If 1476 * we're using kernel memory buffers, then we can 1477 * allocate them here. If we're using zero-copy, 1478 * then the user process must have registered buffers 1479 * by the time we get here. 1480 */ 1481 alloc_buf = 0; 1482 BPFD_LOCK(d); 1483 if (d->bd_bufmode == BPF_BUFMODE_BUFFER && 1484 d->bd_sbuf == NULL) 1485 alloc_buf = 1; 1486 BPFD_UNLOCK(d); 1487 if (alloc_buf) { 1488 size = d->bd_bufsize; 1489 error = bpf_buffer_ioctl_sblen(d, &size); 1490 if (error != 0) 1491 break; 1492 } 1493 BPF_LOCK(); 1494 error = bpf_setif(d, (struct ifreq *)addr); 1495 BPF_UNLOCK(); 1496 break; 1497 } 1498 1499 /* 1500 * Set read timeout. 1501 */ 1502 case BIOCSRTIMEOUT: 1503 #if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1504 case BIOCSRTIMEOUT32: 1505 #endif 1506 { 1507 struct timeval *tv = (struct timeval *)addr; 1508 #if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1509 struct timeval32 *tv32; 1510 struct timeval tv64; 1511 1512 if (cmd == BIOCSRTIMEOUT32) { 1513 tv32 = (struct timeval32 *)addr; 1514 tv = &tv64; 1515 tv->tv_sec = tv32->tv_sec; 1516 tv->tv_usec = tv32->tv_usec; 1517 } else 1518 #endif 1519 tv = (struct timeval *)addr; 1520 1521 /* 1522 * Subtract 1 tick from tvtohz() since this isn't 1523 * a one-shot timer. 1524 */ 1525 if ((error = itimerfix(tv)) == 0) 1526 d->bd_rtout = tvtohz(tv) - 1; 1527 break; 1528 } 1529 1530 /* 1531 * Get read timeout. 1532 */ 1533 case BIOCGRTIMEOUT: 1534 #if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1535 case BIOCGRTIMEOUT32: 1536 #endif 1537 { 1538 struct timeval *tv; 1539 #if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1540 struct timeval32 *tv32; 1541 struct timeval tv64; 1542 1543 if (cmd == BIOCGRTIMEOUT32) 1544 tv = &tv64; 1545 else 1546 #endif 1547 tv = (struct timeval *)addr; 1548 1549 tv->tv_sec = d->bd_rtout / hz; 1550 tv->tv_usec = (d->bd_rtout % hz) * tick; 1551 #if defined(COMPAT_FREEBSD32) && !defined(__mips__) 1552 if (cmd == BIOCGRTIMEOUT32) { 1553 tv32 = (struct timeval32 *)addr; 1554 tv32->tv_sec = tv->tv_sec; 1555 tv32->tv_usec = tv->tv_usec; 1556 } 1557 #endif 1558 1559 break; 1560 } 1561 1562 /* 1563 * Get packet stats. 1564 */ 1565 case BIOCGSTATS: 1566 { 1567 struct bpf_stat *bs = (struct bpf_stat *)addr; 1568 1569 /* XXXCSJP overflow */ 1570 bs->bs_recv = d->bd_rcount; 1571 bs->bs_drop = d->bd_dcount; 1572 break; 1573 } 1574 1575 /* 1576 * Set immediate mode. 1577 */ 1578 case BIOCIMMEDIATE: 1579 BPFD_LOCK(d); 1580 d->bd_immediate = *(u_int *)addr; 1581 BPFD_UNLOCK(d); 1582 break; 1583 1584 case BIOCVERSION: 1585 { 1586 struct bpf_version *bv = (struct bpf_version *)addr; 1587 1588 bv->bv_major = BPF_MAJOR_VERSION; 1589 bv->bv_minor = BPF_MINOR_VERSION; 1590 break; 1591 } 1592 1593 /* 1594 * Get "header already complete" flag 1595 */ 1596 case BIOCGHDRCMPLT: 1597 BPFD_LOCK(d); 1598 *(u_int *)addr = d->bd_hdrcmplt; 1599 BPFD_UNLOCK(d); 1600 break; 1601 1602 /* 1603 * Set "header already complete" flag 1604 */ 1605 case BIOCSHDRCMPLT: 1606 BPFD_LOCK(d); 1607 d->bd_hdrcmplt = *(u_int *)addr ? 1 : 0; 1608 BPFD_UNLOCK(d); 1609 break; 1610 1611 /* 1612 * Get packet direction flag 1613 */ 1614 case BIOCGDIRECTION: 1615 BPFD_LOCK(d); 1616 *(u_int *)addr = d->bd_direction; 1617 BPFD_UNLOCK(d); 1618 break; 1619 1620 /* 1621 * Set packet direction flag 1622 */ 1623 case BIOCSDIRECTION: 1624 { 1625 u_int direction; 1626 1627 direction = *(u_int *)addr; 1628 switch (direction) { 1629 case BPF_D_IN: 1630 case BPF_D_INOUT: 1631 case BPF_D_OUT: 1632 BPFD_LOCK(d); 1633 d->bd_direction = direction; 1634 BPFD_UNLOCK(d); 1635 break; 1636 default: 1637 error = EINVAL; 1638 } 1639 } 1640 break; 1641 1642 /* 1643 * Get packet timestamp format and resolution. 1644 */ 1645 case BIOCGTSTAMP: 1646 BPFD_LOCK(d); 1647 *(u_int *)addr = d->bd_tstamp; 1648 BPFD_UNLOCK(d); 1649 break; 1650 1651 /* 1652 * Set packet timestamp format and resolution. 1653 */ 1654 case BIOCSTSTAMP: 1655 { 1656 u_int func; 1657 1658 func = *(u_int *)addr; 1659 if (BPF_T_VALID(func)) 1660 d->bd_tstamp = func; 1661 else 1662 error = EINVAL; 1663 } 1664 break; 1665 1666 case BIOCFEEDBACK: 1667 BPFD_LOCK(d); 1668 d->bd_feedback = *(u_int *)addr; 1669 BPFD_UNLOCK(d); 1670 break; 1671 1672 case BIOCLOCK: 1673 BPFD_LOCK(d); 1674 d->bd_locked = 1; 1675 BPFD_UNLOCK(d); 1676 break; 1677 1678 case FIONBIO: /* Non-blocking I/O */ 1679 break; 1680 1681 case FIOASYNC: /* Send signal on receive packets */ 1682 BPFD_LOCK(d); 1683 d->bd_async = *(int *)addr; 1684 BPFD_UNLOCK(d); 1685 break; 1686 1687 case FIOSETOWN: 1688 /* 1689 * XXX: Add some sort of locking here? 1690 * fsetown() can sleep. 1691 */ 1692 error = fsetown(*(int *)addr, &d->bd_sigio); 1693 break; 1694 1695 case FIOGETOWN: 1696 BPFD_LOCK(d); 1697 *(int *)addr = fgetown(&d->bd_sigio); 1698 BPFD_UNLOCK(d); 1699 break; 1700 1701 /* This is deprecated, FIOSETOWN should be used instead. */ 1702 case TIOCSPGRP: 1703 error = fsetown(-(*(int *)addr), &d->bd_sigio); 1704 break; 1705 1706 /* This is deprecated, FIOGETOWN should be used instead. */ 1707 case TIOCGPGRP: 1708 *(int *)addr = -fgetown(&d->bd_sigio); 1709 break; 1710 1711 case BIOCSRSIG: /* Set receive signal */ 1712 { 1713 u_int sig; 1714 1715 sig = *(u_int *)addr; 1716 1717 if (sig >= NSIG) 1718 error = EINVAL; 1719 else { 1720 BPFD_LOCK(d); 1721 d->bd_sig = sig; 1722 BPFD_UNLOCK(d); 1723 } 1724 break; 1725 } 1726 case BIOCGRSIG: 1727 BPFD_LOCK(d); 1728 *(u_int *)addr = d->bd_sig; 1729 BPFD_UNLOCK(d); 1730 break; 1731 1732 case BIOCGETBUFMODE: 1733 BPFD_LOCK(d); 1734 *(u_int *)addr = d->bd_bufmode; 1735 BPFD_UNLOCK(d); 1736 break; 1737 1738 case BIOCSETBUFMODE: 1739 /* 1740 * Allow the buffering mode to be changed as long as we 1741 * haven't yet committed to a particular mode. Our 1742 * definition of commitment, for now, is whether or not a 1743 * buffer has been allocated or an interface attached, since 1744 * that's the point where things get tricky. 1745 */ 1746 switch (*(u_int *)addr) { 1747 case BPF_BUFMODE_BUFFER: 1748 break; 1749 1750 case BPF_BUFMODE_ZBUF: 1751 if (bpf_zerocopy_enable) 1752 break; 1753 /* FALLSTHROUGH */ 1754 1755 default: 1756 CURVNET_RESTORE(); 1757 return (EINVAL); 1758 } 1759 1760 BPFD_LOCK(d); 1761 if (d->bd_sbuf != NULL || d->bd_hbuf != NULL || 1762 d->bd_fbuf != NULL || d->bd_bif != NULL) { 1763 BPFD_UNLOCK(d); 1764 CURVNET_RESTORE(); 1765 return (EBUSY); 1766 } 1767 d->bd_bufmode = *(u_int *)addr; 1768 BPFD_UNLOCK(d); 1769 break; 1770 1771 case BIOCGETZMAX: 1772 error = bpf_ioctl_getzmax(td, d, (size_t *)addr); 1773 break; 1774 1775 case BIOCSETZBUF: 1776 error = bpf_ioctl_setzbuf(td, d, (struct bpf_zbuf *)addr); 1777 break; 1778 1779 case BIOCROTZBUF: 1780 error = bpf_ioctl_rotzbuf(td, d, (struct bpf_zbuf *)addr); 1781 break; 1782 } 1783 CURVNET_RESTORE(); 1784 return (error); 1785 } 1786 1787 /* 1788 * Set d's packet filter program to fp. If this file already has a filter, 1789 * free it and replace it. Returns EINVAL for bogus requests. 1790 * 1791 * Note we need global lock here to serialize bpf_setf() and bpf_setif() calls 1792 * since reading d->bd_bif can't be protected by d or interface lock due to 1793 * lock order. 1794 * 1795 * Additionally, we have to acquire interface write lock due to bpf_mtap() uses 1796 * interface read lock to read all filers. 1797 * 1798 */ 1799 static int 1800 bpf_setf(struct bpf_d *d, struct bpf_program *fp, u_long cmd) 1801 { 1802 #ifdef COMPAT_FREEBSD32 1803 struct bpf_program fp_swab; 1804 struct bpf_program32 *fp32; 1805 #endif 1806 struct bpf_insn *fcode, *old; 1807 #ifdef BPF_JITTER 1808 bpf_jit_filter *jfunc, *ofunc; 1809 #endif 1810 size_t size; 1811 u_int flen; 1812 int need_upgrade; 1813 1814 #ifdef COMPAT_FREEBSD32 1815 switch (cmd) { 1816 case BIOCSETF32: 1817 case BIOCSETWF32: 1818 case BIOCSETFNR32: 1819 fp32 = (struct bpf_program32 *)fp; 1820 fp_swab.bf_len = fp32->bf_len; 1821 fp_swab.bf_insns = (struct bpf_insn *)(uintptr_t)fp32->bf_insns; 1822 fp = &fp_swab; 1823 switch (cmd) { 1824 case BIOCSETF32: 1825 cmd = BIOCSETF; 1826 break; 1827 case BIOCSETWF32: 1828 cmd = BIOCSETWF; 1829 break; 1830 } 1831 break; 1832 } 1833 #endif 1834 1835 fcode = NULL; 1836 #ifdef BPF_JITTER 1837 jfunc = ofunc = NULL; 1838 #endif 1839 need_upgrade = 0; 1840 1841 /* 1842 * Check new filter validness before acquiring any locks. 1843 * Allocate memory for new filter, if needed. 1844 */ 1845 flen = fp->bf_len; 1846 if (flen > bpf_maxinsns || (fp->bf_insns == NULL && flen != 0)) 1847 return (EINVAL); 1848 size = flen * sizeof(*fp->bf_insns); 1849 if (size > 0) { 1850 /* We're setting up new filter. Copy and check actual data. */ 1851 fcode = malloc(size, M_BPF, M_WAITOK); 1852 if (copyin(fp->bf_insns, fcode, size) != 0 || 1853 !bpf_validate(fcode, flen)) { 1854 free(fcode, M_BPF); 1855 return (EINVAL); 1856 } 1857 #ifdef BPF_JITTER 1858 /* Filter is copied inside fcode and is perfectly valid. */ 1859 jfunc = bpf_jitter(fcode, flen); 1860 #endif 1861 } 1862 1863 BPF_LOCK(); 1864 1865 /* 1866 * Set up new filter. 1867 * Protect filter change by interface lock. 1868 * Additionally, we are protected by global lock here. 1869 */ 1870 if (d->bd_bif != NULL) 1871 BPFIF_WLOCK(d->bd_bif); 1872 BPFD_LOCK(d); 1873 if (cmd == BIOCSETWF) { 1874 old = d->bd_wfilter; 1875 d->bd_wfilter = fcode; 1876 } else { 1877 old = d->bd_rfilter; 1878 d->bd_rfilter = fcode; 1879 #ifdef BPF_JITTER 1880 ofunc = d->bd_bfilter; 1881 d->bd_bfilter = jfunc; 1882 #endif 1883 if (cmd == BIOCSETF) 1884 reset_d(d); 1885 1886 need_upgrade = bpf_check_upgrade(cmd, d, fcode, flen); 1887 } 1888 BPFD_UNLOCK(d); 1889 if (d->bd_bif != NULL) 1890 BPFIF_WUNLOCK(d->bd_bif); 1891 if (old != NULL) 1892 free(old, M_BPF); 1893 #ifdef BPF_JITTER 1894 if (ofunc != NULL) 1895 bpf_destroy_jit_filter(ofunc); 1896 #endif 1897 1898 /* Move d to active readers list. */ 1899 if (need_upgrade != 0) 1900 bpf_upgraded(d); 1901 1902 BPF_UNLOCK(); 1903 return (0); 1904 } 1905 1906 /* 1907 * Detach a file from its current interface (if attached at all) and attach 1908 * to the interface indicated by the name stored in ifr. 1909 * Return an errno or 0. 1910 */ 1911 static int 1912 bpf_setif(struct bpf_d *d, struct ifreq *ifr) 1913 { 1914 struct bpf_if *bp; 1915 struct ifnet *theywant; 1916 1917 BPF_LOCK_ASSERT(); 1918 1919 theywant = ifunit(ifr->ifr_name); 1920 if (theywant == NULL || theywant->if_bpf == NULL) 1921 return (ENXIO); 1922 1923 bp = theywant->if_bpf; 1924 1925 /* Check if interface is not being detached from BPF */ 1926 BPFIF_RLOCK(bp); 1927 if (bp->bif_flags & BPFIF_FLAG_DYING) { 1928 BPFIF_RUNLOCK(bp); 1929 return (ENXIO); 1930 } 1931 BPFIF_RUNLOCK(bp); 1932 1933 /* 1934 * At this point, we expect the buffer is already allocated. If not, 1935 * return an error. 1936 */ 1937 switch (d->bd_bufmode) { 1938 case BPF_BUFMODE_BUFFER: 1939 case BPF_BUFMODE_ZBUF: 1940 if (d->bd_sbuf == NULL) 1941 return (EINVAL); 1942 break; 1943 1944 default: 1945 panic("bpf_setif: bufmode %d", d->bd_bufmode); 1946 } 1947 if (bp != d->bd_bif) 1948 bpf_attachd(d, bp); 1949 BPFD_LOCK(d); 1950 reset_d(d); 1951 BPFD_UNLOCK(d); 1952 return (0); 1953 } 1954 1955 /* 1956 * Support for select() and poll() system calls 1957 * 1958 * Return true iff the specific operation will not block indefinitely. 1959 * Otherwise, return false but make a note that a selwakeup() must be done. 1960 */ 1961 static int 1962 bpfpoll(struct cdev *dev, int events, struct thread *td) 1963 { 1964 struct bpf_d *d; 1965 int revents; 1966 1967 if (devfs_get_cdevpriv((void **)&d) != 0 || d->bd_bif == NULL) 1968 return (events & 1969 (POLLHUP|POLLIN|POLLRDNORM|POLLOUT|POLLWRNORM)); 1970 1971 /* 1972 * Refresh PID associated with this descriptor. 1973 */ 1974 revents = events & (POLLOUT | POLLWRNORM); 1975 BPFD_LOCK(d); 1976 BPF_PID_REFRESH(d, td); 1977 if (events & (POLLIN | POLLRDNORM)) { 1978 if (bpf_ready(d)) 1979 revents |= events & (POLLIN | POLLRDNORM); 1980 else { 1981 selrecord(td, &d->bd_sel); 1982 /* Start the read timeout if necessary. */ 1983 if (d->bd_rtout > 0 && d->bd_state == BPF_IDLE) { 1984 callout_reset(&d->bd_callout, d->bd_rtout, 1985 bpf_timed_out, d); 1986 d->bd_state = BPF_WAITING; 1987 } 1988 } 1989 } 1990 BPFD_UNLOCK(d); 1991 return (revents); 1992 } 1993 1994 /* 1995 * Support for kevent() system call. Register EVFILT_READ filters and 1996 * reject all others. 1997 */ 1998 int 1999 bpfkqfilter(struct cdev *dev, struct knote *kn) 2000 { 2001 struct bpf_d *d; 2002 2003 if (devfs_get_cdevpriv((void **)&d) != 0 || 2004 kn->kn_filter != EVFILT_READ) 2005 return (1); 2006 2007 /* 2008 * Refresh PID associated with this descriptor. 2009 */ 2010 BPFD_LOCK(d); 2011 BPF_PID_REFRESH_CUR(d); 2012 kn->kn_fop = &bpfread_filtops; 2013 kn->kn_hook = d; 2014 knlist_add(&d->bd_sel.si_note, kn, 1); 2015 BPFD_UNLOCK(d); 2016 2017 return (0); 2018 } 2019 2020 static void 2021 filt_bpfdetach(struct knote *kn) 2022 { 2023 struct bpf_d *d = (struct bpf_d *)kn->kn_hook; 2024 2025 knlist_remove(&d->bd_sel.si_note, kn, 0); 2026 } 2027 2028 static int 2029 filt_bpfread(struct knote *kn, long hint) 2030 { 2031 struct bpf_d *d = (struct bpf_d *)kn->kn_hook; 2032 int ready; 2033 2034 BPFD_LOCK_ASSERT(d); 2035 ready = bpf_ready(d); 2036 if (ready) { 2037 kn->kn_data = d->bd_slen; 2038 /* 2039 * Ignore the hold buffer if it is being copied to user space. 2040 */ 2041 if (!d->bd_hbuf_in_use && d->bd_hbuf) 2042 kn->kn_data += d->bd_hlen; 2043 } else if (d->bd_rtout > 0 && d->bd_state == BPF_IDLE) { 2044 callout_reset(&d->bd_callout, d->bd_rtout, 2045 bpf_timed_out, d); 2046 d->bd_state = BPF_WAITING; 2047 } 2048 2049 return (ready); 2050 } 2051 2052 #define BPF_TSTAMP_NONE 0 2053 #define BPF_TSTAMP_FAST 1 2054 #define BPF_TSTAMP_NORMAL 2 2055 #define BPF_TSTAMP_EXTERN 3 2056 2057 static int 2058 bpf_ts_quality(int tstype) 2059 { 2060 2061 if (tstype == BPF_T_NONE) 2062 return (BPF_TSTAMP_NONE); 2063 if ((tstype & BPF_T_FAST) != 0) 2064 return (BPF_TSTAMP_FAST); 2065 2066 return (BPF_TSTAMP_NORMAL); 2067 } 2068 2069 static int 2070 bpf_gettime(struct bintime *bt, int tstype, struct mbuf *m) 2071 { 2072 struct m_tag *tag; 2073 int quality; 2074 2075 quality = bpf_ts_quality(tstype); 2076 if (quality == BPF_TSTAMP_NONE) 2077 return (quality); 2078 2079 if (m != NULL) { 2080 tag = m_tag_locate(m, MTAG_BPF, MTAG_BPF_TIMESTAMP, NULL); 2081 if (tag != NULL) { 2082 *bt = *(struct bintime *)(tag + 1); 2083 return (BPF_TSTAMP_EXTERN); 2084 } 2085 } 2086 if (quality == BPF_TSTAMP_NORMAL) 2087 binuptime(bt); 2088 else 2089 getbinuptime(bt); 2090 2091 return (quality); 2092 } 2093 2094 /* 2095 * Incoming linkage from device drivers. Process the packet pkt, of length 2096 * pktlen, which is stored in a contiguous buffer. The packet is parsed 2097 * by each process' filter, and if accepted, stashed into the corresponding 2098 * buffer. 2099 */ 2100 void 2101 bpf_tap(struct bpf_if *bp, u_char *pkt, u_int pktlen) 2102 { 2103 struct bintime bt; 2104 struct bpf_d *d; 2105 #ifdef BPF_JITTER 2106 bpf_jit_filter *bf; 2107 #endif 2108 u_int slen; 2109 int gottime; 2110 2111 gottime = BPF_TSTAMP_NONE; 2112 2113 BPFIF_RLOCK(bp); 2114 2115 LIST_FOREACH(d, &bp->bif_dlist, bd_next) { 2116 /* 2117 * We are not using any locks for d here because: 2118 * 1) any filter change is protected by interface 2119 * write lock 2120 * 2) destroying/detaching d is protected by interface 2121 * write lock, too 2122 */ 2123 2124 /* XXX: Do not protect counter for the sake of performance. */ 2125 ++d->bd_rcount; 2126 /* 2127 * NB: We dont call BPF_CHECK_DIRECTION() here since there is no 2128 * way for the caller to indiciate to us whether this packet 2129 * is inbound or outbound. In the bpf_mtap() routines, we use 2130 * the interface pointers on the mbuf to figure it out. 2131 */ 2132 #ifdef BPF_JITTER 2133 bf = bpf_jitter_enable != 0 ? d->bd_bfilter : NULL; 2134 if (bf != NULL) 2135 slen = (*(bf->func))(pkt, pktlen, pktlen); 2136 else 2137 #endif 2138 slen = bpf_filter(d->bd_rfilter, pkt, pktlen, pktlen); 2139 if (slen != 0) { 2140 /* 2141 * Filter matches. Let's to acquire write lock. 2142 */ 2143 BPFD_LOCK(d); 2144 2145 d->bd_fcount++; 2146 if (gottime < bpf_ts_quality(d->bd_tstamp)) 2147 gottime = bpf_gettime(&bt, d->bd_tstamp, NULL); 2148 #ifdef MAC 2149 if (mac_bpfdesc_check_receive(d, bp->bif_ifp) == 0) 2150 #endif 2151 catchpacket(d, pkt, pktlen, slen, 2152 bpf_append_bytes, &bt); 2153 BPFD_UNLOCK(d); 2154 } 2155 } 2156 BPFIF_RUNLOCK(bp); 2157 } 2158 2159 #define BPF_CHECK_DIRECTION(d, r, i) \ 2160 (((d)->bd_direction == BPF_D_IN && (r) != (i)) || \ 2161 ((d)->bd_direction == BPF_D_OUT && (r) == (i))) 2162 2163 /* 2164 * Incoming linkage from device drivers, when packet is in an mbuf chain. 2165 * Locking model is explained in bpf_tap(). 2166 */ 2167 void 2168 bpf_mtap(struct bpf_if *bp, struct mbuf *m) 2169 { 2170 struct bintime bt; 2171 struct bpf_d *d; 2172 #ifdef BPF_JITTER 2173 bpf_jit_filter *bf; 2174 #endif 2175 u_int pktlen, slen; 2176 int gottime; 2177 2178 /* Skip outgoing duplicate packets. */ 2179 if ((m->m_flags & M_PROMISC) != 0 && m->m_pkthdr.rcvif == NULL) { 2180 m->m_flags &= ~M_PROMISC; 2181 return; 2182 } 2183 2184 pktlen = m_length(m, NULL); 2185 gottime = BPF_TSTAMP_NONE; 2186 2187 BPFIF_RLOCK(bp); 2188 2189 LIST_FOREACH(d, &bp->bif_dlist, bd_next) { 2190 if (BPF_CHECK_DIRECTION(d, m->m_pkthdr.rcvif, bp->bif_ifp)) 2191 continue; 2192 ++d->bd_rcount; 2193 #ifdef BPF_JITTER 2194 bf = bpf_jitter_enable != 0 ? d->bd_bfilter : NULL; 2195 /* XXX We cannot handle multiple mbufs. */ 2196 if (bf != NULL && m->m_next == NULL) 2197 slen = (*(bf->func))(mtod(m, u_char *), pktlen, pktlen); 2198 else 2199 #endif 2200 slen = bpf_filter(d->bd_rfilter, (u_char *)m, pktlen, 0); 2201 if (slen != 0) { 2202 BPFD_LOCK(d); 2203 2204 d->bd_fcount++; 2205 if (gottime < bpf_ts_quality(d->bd_tstamp)) 2206 gottime = bpf_gettime(&bt, d->bd_tstamp, m); 2207 #ifdef MAC 2208 if (mac_bpfdesc_check_receive(d, bp->bif_ifp) == 0) 2209 #endif 2210 catchpacket(d, (u_char *)m, pktlen, slen, 2211 bpf_append_mbuf, &bt); 2212 BPFD_UNLOCK(d); 2213 } 2214 } 2215 BPFIF_RUNLOCK(bp); 2216 } 2217 2218 /* 2219 * Incoming linkage from device drivers, when packet is in 2220 * an mbuf chain and to be prepended by a contiguous header. 2221 */ 2222 void 2223 bpf_mtap2(struct bpf_if *bp, void *data, u_int dlen, struct mbuf *m) 2224 { 2225 struct bintime bt; 2226 struct mbuf mb; 2227 struct bpf_d *d; 2228 u_int pktlen, slen; 2229 int gottime; 2230 2231 /* Skip outgoing duplicate packets. */ 2232 if ((m->m_flags & M_PROMISC) != 0 && m->m_pkthdr.rcvif == NULL) { 2233 m->m_flags &= ~M_PROMISC; 2234 return; 2235 } 2236 2237 pktlen = m_length(m, NULL); 2238 /* 2239 * Craft on-stack mbuf suitable for passing to bpf_filter. 2240 * Note that we cut corners here; we only setup what's 2241 * absolutely needed--this mbuf should never go anywhere else. 2242 */ 2243 mb.m_next = m; 2244 mb.m_data = data; 2245 mb.m_len = dlen; 2246 pktlen += dlen; 2247 2248 gottime = BPF_TSTAMP_NONE; 2249 2250 BPFIF_RLOCK(bp); 2251 2252 LIST_FOREACH(d, &bp->bif_dlist, bd_next) { 2253 if (BPF_CHECK_DIRECTION(d, m->m_pkthdr.rcvif, bp->bif_ifp)) 2254 continue; 2255 ++d->bd_rcount; 2256 slen = bpf_filter(d->bd_rfilter, (u_char *)&mb, pktlen, 0); 2257 if (slen != 0) { 2258 BPFD_LOCK(d); 2259 2260 d->bd_fcount++; 2261 if (gottime < bpf_ts_quality(d->bd_tstamp)) 2262 gottime = bpf_gettime(&bt, d->bd_tstamp, m); 2263 #ifdef MAC 2264 if (mac_bpfdesc_check_receive(d, bp->bif_ifp) == 0) 2265 #endif 2266 catchpacket(d, (u_char *)&mb, pktlen, slen, 2267 bpf_append_mbuf, &bt); 2268 BPFD_UNLOCK(d); 2269 } 2270 } 2271 BPFIF_RUNLOCK(bp); 2272 } 2273 2274 #undef BPF_CHECK_DIRECTION 2275 2276 #undef BPF_TSTAMP_NONE 2277 #undef BPF_TSTAMP_FAST 2278 #undef BPF_TSTAMP_NORMAL 2279 #undef BPF_TSTAMP_EXTERN 2280 2281 static int 2282 bpf_hdrlen(struct bpf_d *d) 2283 { 2284 int hdrlen; 2285 2286 hdrlen = d->bd_bif->bif_hdrlen; 2287 #ifndef BURN_BRIDGES 2288 if (d->bd_tstamp == BPF_T_NONE || 2289 BPF_T_FORMAT(d->bd_tstamp) == BPF_T_MICROTIME) 2290 #ifdef COMPAT_FREEBSD32 2291 if (d->bd_compat32) 2292 hdrlen += SIZEOF_BPF_HDR(struct bpf_hdr32); 2293 else 2294 #endif 2295 hdrlen += SIZEOF_BPF_HDR(struct bpf_hdr); 2296 else 2297 #endif 2298 hdrlen += SIZEOF_BPF_HDR(struct bpf_xhdr); 2299 #ifdef COMPAT_FREEBSD32 2300 if (d->bd_compat32) 2301 hdrlen = BPF_WORDALIGN32(hdrlen); 2302 else 2303 #endif 2304 hdrlen = BPF_WORDALIGN(hdrlen); 2305 2306 return (hdrlen - d->bd_bif->bif_hdrlen); 2307 } 2308 2309 static void 2310 bpf_bintime2ts(struct bintime *bt, struct bpf_ts *ts, int tstype) 2311 { 2312 struct bintime bt2; 2313 struct timeval tsm; 2314 struct timespec tsn; 2315 2316 if ((tstype & BPF_T_MONOTONIC) == 0) { 2317 bt2 = *bt; 2318 bintime_add(&bt2, &boottimebin); 2319 bt = &bt2; 2320 } 2321 switch (BPF_T_FORMAT(tstype)) { 2322 case BPF_T_MICROTIME: 2323 bintime2timeval(bt, &tsm); 2324 ts->bt_sec = tsm.tv_sec; 2325 ts->bt_frac = tsm.tv_usec; 2326 break; 2327 case BPF_T_NANOTIME: 2328 bintime2timespec(bt, &tsn); 2329 ts->bt_sec = tsn.tv_sec; 2330 ts->bt_frac = tsn.tv_nsec; 2331 break; 2332 case BPF_T_BINTIME: 2333 ts->bt_sec = bt->sec; 2334 ts->bt_frac = bt->frac; 2335 break; 2336 } 2337 } 2338 2339 /* 2340 * Move the packet data from interface memory (pkt) into the 2341 * store buffer. "cpfn" is the routine called to do the actual data 2342 * transfer. bcopy is passed in to copy contiguous chunks, while 2343 * bpf_append_mbuf is passed in to copy mbuf chains. In the latter case, 2344 * pkt is really an mbuf. 2345 */ 2346 static void 2347 catchpacket(struct bpf_d *d, u_char *pkt, u_int pktlen, u_int snaplen, 2348 void (*cpfn)(struct bpf_d *, caddr_t, u_int, void *, u_int), 2349 struct bintime *bt) 2350 { 2351 struct bpf_xhdr hdr; 2352 #ifndef BURN_BRIDGES 2353 struct bpf_hdr hdr_old; 2354 #ifdef COMPAT_FREEBSD32 2355 struct bpf_hdr32 hdr32_old; 2356 #endif 2357 #endif 2358 int caplen, curlen, hdrlen, totlen; 2359 int do_wakeup = 0; 2360 int do_timestamp; 2361 int tstype; 2362 2363 BPFD_LOCK_ASSERT(d); 2364 2365 /* 2366 * Detect whether user space has released a buffer back to us, and if 2367 * so, move it from being a hold buffer to a free buffer. This may 2368 * not be the best place to do it (for example, we might only want to 2369 * run this check if we need the space), but for now it's a reliable 2370 * spot to do it. 2371 */ 2372 if (d->bd_fbuf == NULL && bpf_canfreebuf(d)) { 2373 d->bd_fbuf = d->bd_hbuf; 2374 d->bd_hbuf = NULL; 2375 d->bd_hlen = 0; 2376 bpf_buf_reclaimed(d); 2377 } 2378 2379 /* 2380 * Figure out how many bytes to move. If the packet is 2381 * greater or equal to the snapshot length, transfer that 2382 * much. Otherwise, transfer the whole packet (unless 2383 * we hit the buffer size limit). 2384 */ 2385 hdrlen = bpf_hdrlen(d); 2386 totlen = hdrlen + min(snaplen, pktlen); 2387 if (totlen > d->bd_bufsize) 2388 totlen = d->bd_bufsize; 2389 2390 /* 2391 * Round up the end of the previous packet to the next longword. 2392 * 2393 * Drop the packet if there's no room and no hope of room 2394 * If the packet would overflow the storage buffer or the storage 2395 * buffer is considered immutable by the buffer model, try to rotate 2396 * the buffer and wakeup pending processes. 2397 */ 2398 #ifdef COMPAT_FREEBSD32 2399 if (d->bd_compat32) 2400 curlen = BPF_WORDALIGN32(d->bd_slen); 2401 else 2402 #endif 2403 curlen = BPF_WORDALIGN(d->bd_slen); 2404 if (curlen + totlen > d->bd_bufsize || !bpf_canwritebuf(d)) { 2405 if (d->bd_fbuf == NULL) { 2406 /* 2407 * There's no room in the store buffer, and no 2408 * prospect of room, so drop the packet. Notify the 2409 * buffer model. 2410 */ 2411 bpf_buffull(d); 2412 ++d->bd_dcount; 2413 return; 2414 } 2415 KASSERT(!d->bd_hbuf_in_use, ("hold buffer is in use")); 2416 ROTATE_BUFFERS(d); 2417 do_wakeup = 1; 2418 curlen = 0; 2419 } else if (d->bd_immediate || d->bd_state == BPF_TIMED_OUT) 2420 /* 2421 * Immediate mode is set, or the read timeout has already 2422 * expired during a select call. A packet arrived, so the 2423 * reader should be woken up. 2424 */ 2425 do_wakeup = 1; 2426 caplen = totlen - hdrlen; 2427 tstype = d->bd_tstamp; 2428 do_timestamp = tstype != BPF_T_NONE; 2429 #ifndef BURN_BRIDGES 2430 if (tstype == BPF_T_NONE || BPF_T_FORMAT(tstype) == BPF_T_MICROTIME) { 2431 struct bpf_ts ts; 2432 if (do_timestamp) 2433 bpf_bintime2ts(bt, &ts, tstype); 2434 #ifdef COMPAT_FREEBSD32 2435 if (d->bd_compat32) { 2436 bzero(&hdr32_old, sizeof(hdr32_old)); 2437 if (do_timestamp) { 2438 hdr32_old.bh_tstamp.tv_sec = ts.bt_sec; 2439 hdr32_old.bh_tstamp.tv_usec = ts.bt_frac; 2440 } 2441 hdr32_old.bh_datalen = pktlen; 2442 hdr32_old.bh_hdrlen = hdrlen; 2443 hdr32_old.bh_caplen = caplen; 2444 bpf_append_bytes(d, d->bd_sbuf, curlen, &hdr32_old, 2445 sizeof(hdr32_old)); 2446 goto copy; 2447 } 2448 #endif 2449 bzero(&hdr_old, sizeof(hdr_old)); 2450 if (do_timestamp) { 2451 hdr_old.bh_tstamp.tv_sec = ts.bt_sec; 2452 hdr_old.bh_tstamp.tv_usec = ts.bt_frac; 2453 } 2454 hdr_old.bh_datalen = pktlen; 2455 hdr_old.bh_hdrlen = hdrlen; 2456 hdr_old.bh_caplen = caplen; 2457 bpf_append_bytes(d, d->bd_sbuf, curlen, &hdr_old, 2458 sizeof(hdr_old)); 2459 goto copy; 2460 } 2461 #endif 2462 2463 /* 2464 * Append the bpf header. Note we append the actual header size, but 2465 * move forward the length of the header plus padding. 2466 */ 2467 bzero(&hdr, sizeof(hdr)); 2468 if (do_timestamp) 2469 bpf_bintime2ts(bt, &hdr.bh_tstamp, tstype); 2470 hdr.bh_datalen = pktlen; 2471 hdr.bh_hdrlen = hdrlen; 2472 hdr.bh_caplen = caplen; 2473 bpf_append_bytes(d, d->bd_sbuf, curlen, &hdr, sizeof(hdr)); 2474 2475 /* 2476 * Copy the packet data into the store buffer and update its length. 2477 */ 2478 #ifndef BURN_BRIDGES 2479 copy: 2480 #endif 2481 (*cpfn)(d, d->bd_sbuf, curlen + hdrlen, pkt, caplen); 2482 d->bd_slen = curlen + totlen; 2483 2484 if (do_wakeup) 2485 bpf_wakeup(d); 2486 } 2487 2488 /* 2489 * Free buffers currently in use by a descriptor. 2490 * Called on close. 2491 */ 2492 static void 2493 bpf_freed(struct bpf_d *d) 2494 { 2495 2496 /* 2497 * We don't need to lock out interrupts since this descriptor has 2498 * been detached from its interface and it yet hasn't been marked 2499 * free. 2500 */ 2501 bpf_free(d); 2502 if (d->bd_rfilter != NULL) { 2503 free((caddr_t)d->bd_rfilter, M_BPF); 2504 #ifdef BPF_JITTER 2505 if (d->bd_bfilter != NULL) 2506 bpf_destroy_jit_filter(d->bd_bfilter); 2507 #endif 2508 } 2509 if (d->bd_wfilter != NULL) 2510 free((caddr_t)d->bd_wfilter, M_BPF); 2511 mtx_destroy(&d->bd_lock); 2512 } 2513 2514 /* 2515 * Attach an interface to bpf. dlt is the link layer type; hdrlen is the 2516 * fixed size of the link header (variable length headers not yet supported). 2517 */ 2518 void 2519 bpfattach(struct ifnet *ifp, u_int dlt, u_int hdrlen) 2520 { 2521 2522 bpfattach2(ifp, dlt, hdrlen, &ifp->if_bpf); 2523 } 2524 2525 /* 2526 * Attach an interface to bpf. ifp is a pointer to the structure 2527 * defining the interface to be attached, dlt is the link layer type, 2528 * and hdrlen is the fixed size of the link header (variable length 2529 * headers are not yet supporrted). 2530 */ 2531 void 2532 bpfattach2(struct ifnet *ifp, u_int dlt, u_int hdrlen, struct bpf_if **driverp) 2533 { 2534 struct bpf_if *bp; 2535 2536 bp = malloc(sizeof(*bp), M_BPF, M_NOWAIT | M_ZERO); 2537 if (bp == NULL) 2538 panic("bpfattach"); 2539 2540 LIST_INIT(&bp->bif_dlist); 2541 LIST_INIT(&bp->bif_wlist); 2542 bp->bif_ifp = ifp; 2543 bp->bif_dlt = dlt; 2544 rw_init(&bp->bif_lock, "bpf interface lock"); 2545 KASSERT(*driverp == NULL, ("bpfattach2: driverp already initialized")); 2546 *driverp = bp; 2547 2548 BPF_LOCK(); 2549 LIST_INSERT_HEAD(&bpf_iflist, bp, bif_next); 2550 BPF_UNLOCK(); 2551 2552 bp->bif_hdrlen = hdrlen; 2553 2554 if (bootverbose) 2555 if_printf(ifp, "bpf attached\n"); 2556 } 2557 2558 /* 2559 * Detach bpf from an interface. This involves detaching each descriptor 2560 * associated with the interface. Notify each descriptor as it's detached 2561 * so that any sleepers wake up and get ENXIO. 2562 */ 2563 void 2564 bpfdetach(struct ifnet *ifp) 2565 { 2566 struct bpf_if *bp, *bp_temp; 2567 struct bpf_d *d; 2568 int ndetached; 2569 2570 ndetached = 0; 2571 2572 BPF_LOCK(); 2573 /* Find all bpf_if struct's which reference ifp and detach them. */ 2574 LIST_FOREACH_SAFE(bp, &bpf_iflist, bif_next, bp_temp) { 2575 if (ifp != bp->bif_ifp) 2576 continue; 2577 2578 LIST_REMOVE(bp, bif_next); 2579 /* Add to to-be-freed list */ 2580 LIST_INSERT_HEAD(&bpf_freelist, bp, bif_next); 2581 2582 ndetached++; 2583 /* 2584 * Delay freeing bp till interface is detached 2585 * and all routes through this interface are removed. 2586 * Mark bp as detached to restrict new consumers. 2587 */ 2588 BPFIF_WLOCK(bp); 2589 bp->bif_flags |= BPFIF_FLAG_DYING; 2590 BPFIF_WUNLOCK(bp); 2591 2592 CTR4(KTR_NET, "%s: sheduling free for encap %d (%p) for if %p", 2593 __func__, bp->bif_dlt, bp, ifp); 2594 2595 /* Free common descriptors */ 2596 while ((d = LIST_FIRST(&bp->bif_dlist)) != NULL) { 2597 bpf_detachd_locked(d); 2598 BPFD_LOCK(d); 2599 bpf_wakeup(d); 2600 BPFD_UNLOCK(d); 2601 } 2602 2603 /* Free writer-only descriptors */ 2604 while ((d = LIST_FIRST(&bp->bif_wlist)) != NULL) { 2605 bpf_detachd_locked(d); 2606 BPFD_LOCK(d); 2607 bpf_wakeup(d); 2608 BPFD_UNLOCK(d); 2609 } 2610 } 2611 BPF_UNLOCK(); 2612 2613 #ifdef INVARIANTS 2614 if (ndetached == 0) 2615 printf("bpfdetach: %s was not attached\n", ifp->if_xname); 2616 #endif 2617 } 2618 2619 /* 2620 * Interface departure handler. 2621 * Note departure event does not guarantee interface is going down. 2622 * Interface renaming is currently done via departure/arrival event set. 2623 * 2624 * Departure handled is called after all routes pointing to 2625 * given interface are removed and interface is in down state 2626 * restricting any packets to be sent/received. We assume it is now safe 2627 * to free data allocated by BPF. 2628 */ 2629 static void 2630 bpf_ifdetach(void *arg __unused, struct ifnet *ifp) 2631 { 2632 struct bpf_if *bp, *bp_temp; 2633 int nmatched = 0; 2634 2635 BPF_LOCK(); 2636 /* 2637 * Find matching entries in free list. 2638 * Nothing should be found if bpfdetach() was not called. 2639 */ 2640 LIST_FOREACH_SAFE(bp, &bpf_freelist, bif_next, bp_temp) { 2641 if (ifp != bp->bif_ifp) 2642 continue; 2643 2644 CTR3(KTR_NET, "%s: freeing BPF instance %p for interface %p", 2645 __func__, bp, ifp); 2646 2647 LIST_REMOVE(bp, bif_next); 2648 2649 rw_destroy(&bp->bif_lock); 2650 free(bp, M_BPF); 2651 2652 nmatched++; 2653 } 2654 BPF_UNLOCK(); 2655 2656 /* 2657 * Note that we cannot zero other pointers to 2658 * custom DLTs possibly used by given interface. 2659 */ 2660 if (nmatched != 0) 2661 ifp->if_bpf = NULL; 2662 } 2663 2664 /* 2665 * Get a list of available data link type of the interface. 2666 */ 2667 static int 2668 bpf_getdltlist(struct bpf_d *d, struct bpf_dltlist *bfl) 2669 { 2670 int n, error; 2671 struct ifnet *ifp; 2672 struct bpf_if *bp; 2673 2674 BPF_LOCK_ASSERT(); 2675 2676 ifp = d->bd_bif->bif_ifp; 2677 n = 0; 2678 error = 0; 2679 LIST_FOREACH(bp, &bpf_iflist, bif_next) { 2680 if (bp->bif_ifp != ifp) 2681 continue; 2682 if (bfl->bfl_list != NULL) { 2683 if (n >= bfl->bfl_len) 2684 return (ENOMEM); 2685 error = copyout(&bp->bif_dlt, 2686 bfl->bfl_list + n, sizeof(u_int)); 2687 } 2688 n++; 2689 } 2690 bfl->bfl_len = n; 2691 return (error); 2692 } 2693 2694 /* 2695 * Set the data link type of a BPF instance. 2696 */ 2697 static int 2698 bpf_setdlt(struct bpf_d *d, u_int dlt) 2699 { 2700 int error, opromisc; 2701 struct ifnet *ifp; 2702 struct bpf_if *bp; 2703 2704 BPF_LOCK_ASSERT(); 2705 2706 if (d->bd_bif->bif_dlt == dlt) 2707 return (0); 2708 ifp = d->bd_bif->bif_ifp; 2709 2710 LIST_FOREACH(bp, &bpf_iflist, bif_next) { 2711 if (bp->bif_ifp == ifp && bp->bif_dlt == dlt) 2712 break; 2713 } 2714 2715 if (bp != NULL) { 2716 opromisc = d->bd_promisc; 2717 bpf_attachd(d, bp); 2718 BPFD_LOCK(d); 2719 reset_d(d); 2720 BPFD_UNLOCK(d); 2721 if (opromisc) { 2722 error = ifpromisc(bp->bif_ifp, 1); 2723 if (error) 2724 if_printf(bp->bif_ifp, 2725 "bpf_setdlt: ifpromisc failed (%d)\n", 2726 error); 2727 else 2728 d->bd_promisc = 1; 2729 } 2730 } 2731 return (bp == NULL ? EINVAL : 0); 2732 } 2733 2734 static void 2735 bpf_drvinit(void *unused) 2736 { 2737 struct cdev *dev; 2738 2739 mtx_init(&bpf_mtx, "bpf global lock", NULL, MTX_DEF); 2740 LIST_INIT(&bpf_iflist); 2741 LIST_INIT(&bpf_freelist); 2742 2743 dev = make_dev(&bpf_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, "bpf"); 2744 /* For compatibility */ 2745 make_dev_alias(dev, "bpf0"); 2746 2747 /* Register interface departure handler */ 2748 bpf_ifdetach_cookie = EVENTHANDLER_REGISTER( 2749 ifnet_departure_event, bpf_ifdetach, NULL, 2750 EVENTHANDLER_PRI_ANY); 2751 } 2752 2753 /* 2754 * Zero out the various packet counters associated with all of the bpf 2755 * descriptors. At some point, we will probably want to get a bit more 2756 * granular and allow the user to specify descriptors to be zeroed. 2757 */ 2758 static void 2759 bpf_zero_counters(void) 2760 { 2761 struct bpf_if *bp; 2762 struct bpf_d *bd; 2763 2764 BPF_LOCK(); 2765 LIST_FOREACH(bp, &bpf_iflist, bif_next) { 2766 BPFIF_RLOCK(bp); 2767 LIST_FOREACH(bd, &bp->bif_dlist, bd_next) { 2768 BPFD_LOCK(bd); 2769 bd->bd_rcount = 0; 2770 bd->bd_dcount = 0; 2771 bd->bd_fcount = 0; 2772 bd->bd_wcount = 0; 2773 bd->bd_wfcount = 0; 2774 bd->bd_zcopy = 0; 2775 BPFD_UNLOCK(bd); 2776 } 2777 BPFIF_RUNLOCK(bp); 2778 } 2779 BPF_UNLOCK(); 2780 } 2781 2782 /* 2783 * Fill filter statistics 2784 */ 2785 static void 2786 bpfstats_fill_xbpf(struct xbpf_d *d, struct bpf_d *bd) 2787 { 2788 2789 bzero(d, sizeof(*d)); 2790 BPFD_LOCK_ASSERT(bd); 2791 d->bd_structsize = sizeof(*d); 2792 /* XXX: reading should be protected by global lock */ 2793 d->bd_immediate = bd->bd_immediate; 2794 d->bd_promisc = bd->bd_promisc; 2795 d->bd_hdrcmplt = bd->bd_hdrcmplt; 2796 d->bd_direction = bd->bd_direction; 2797 d->bd_feedback = bd->bd_feedback; 2798 d->bd_async = bd->bd_async; 2799 d->bd_rcount = bd->bd_rcount; 2800 d->bd_dcount = bd->bd_dcount; 2801 d->bd_fcount = bd->bd_fcount; 2802 d->bd_sig = bd->bd_sig; 2803 d->bd_slen = bd->bd_slen; 2804 d->bd_hlen = bd->bd_hlen; 2805 d->bd_bufsize = bd->bd_bufsize; 2806 d->bd_pid = bd->bd_pid; 2807 strlcpy(d->bd_ifname, 2808 bd->bd_bif->bif_ifp->if_xname, IFNAMSIZ); 2809 d->bd_locked = bd->bd_locked; 2810 d->bd_wcount = bd->bd_wcount; 2811 d->bd_wdcount = bd->bd_wdcount; 2812 d->bd_wfcount = bd->bd_wfcount; 2813 d->bd_zcopy = bd->bd_zcopy; 2814 d->bd_bufmode = bd->bd_bufmode; 2815 } 2816 2817 /* 2818 * Handle `netstat -B' stats request 2819 */ 2820 static int 2821 bpf_stats_sysctl(SYSCTL_HANDLER_ARGS) 2822 { 2823 static const struct xbpf_d zerostats; 2824 struct xbpf_d *xbdbuf, *xbd, tempstats; 2825 int index, error; 2826 struct bpf_if *bp; 2827 struct bpf_d *bd; 2828 2829 /* 2830 * XXX This is not technically correct. It is possible for non 2831 * privileged users to open bpf devices. It would make sense 2832 * if the users who opened the devices were able to retrieve 2833 * the statistics for them, too. 2834 */ 2835 error = priv_check(req->td, PRIV_NET_BPF); 2836 if (error) 2837 return (error); 2838 /* 2839 * Check to see if the user is requesting that the counters be 2840 * zeroed out. Explicitly check that the supplied data is zeroed, 2841 * as we aren't allowing the user to set the counters currently. 2842 */ 2843 if (req->newptr != NULL) { 2844 if (req->newlen != sizeof(tempstats)) 2845 return (EINVAL); 2846 memset(&tempstats, 0, sizeof(tempstats)); 2847 error = SYSCTL_IN(req, &tempstats, sizeof(tempstats)); 2848 if (error) 2849 return (error); 2850 if (bcmp(&tempstats, &zerostats, sizeof(tempstats)) != 0) 2851 return (EINVAL); 2852 bpf_zero_counters(); 2853 return (0); 2854 } 2855 if (req->oldptr == NULL) 2856 return (SYSCTL_OUT(req, 0, bpf_bpfd_cnt * sizeof(*xbd))); 2857 if (bpf_bpfd_cnt == 0) 2858 return (SYSCTL_OUT(req, 0, 0)); 2859 xbdbuf = malloc(req->oldlen, M_BPF, M_WAITOK); 2860 BPF_LOCK(); 2861 if (req->oldlen < (bpf_bpfd_cnt * sizeof(*xbd))) { 2862 BPF_UNLOCK(); 2863 free(xbdbuf, M_BPF); 2864 return (ENOMEM); 2865 } 2866 index = 0; 2867 LIST_FOREACH(bp, &bpf_iflist, bif_next) { 2868 BPFIF_RLOCK(bp); 2869 /* Send writers-only first */ 2870 LIST_FOREACH(bd, &bp->bif_wlist, bd_next) { 2871 xbd = &xbdbuf[index++]; 2872 BPFD_LOCK(bd); 2873 bpfstats_fill_xbpf(xbd, bd); 2874 BPFD_UNLOCK(bd); 2875 } 2876 LIST_FOREACH(bd, &bp->bif_dlist, bd_next) { 2877 xbd = &xbdbuf[index++]; 2878 BPFD_LOCK(bd); 2879 bpfstats_fill_xbpf(xbd, bd); 2880 BPFD_UNLOCK(bd); 2881 } 2882 BPFIF_RUNLOCK(bp); 2883 } 2884 BPF_UNLOCK(); 2885 error = SYSCTL_OUT(req, xbdbuf, index * sizeof(*xbd)); 2886 free(xbdbuf, M_BPF); 2887 return (error); 2888 } 2889 2890 SYSINIT(bpfdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE,bpf_drvinit,NULL); 2891 2892 #else /* !DEV_BPF && !NETGRAPH_BPF */ 2893 /* 2894 * NOP stubs to allow bpf-using drivers to load and function. 2895 * 2896 * A 'better' implementation would allow the core bpf functionality 2897 * to be loaded at runtime. 2898 */ 2899 static struct bpf_if bp_null; 2900 2901 void 2902 bpf_tap(struct bpf_if *bp, u_char *pkt, u_int pktlen) 2903 { 2904 } 2905 2906 void 2907 bpf_mtap(struct bpf_if *bp, struct mbuf *m) 2908 { 2909 } 2910 2911 void 2912 bpf_mtap2(struct bpf_if *bp, void *d, u_int l, struct mbuf *m) 2913 { 2914 } 2915 2916 void 2917 bpfattach(struct ifnet *ifp, u_int dlt, u_int hdrlen) 2918 { 2919 2920 bpfattach2(ifp, dlt, hdrlen, &ifp->if_bpf); 2921 } 2922 2923 void 2924 bpfattach2(struct ifnet *ifp, u_int dlt, u_int hdrlen, struct bpf_if **driverp) 2925 { 2926 2927 *driverp = &bp_null; 2928 } 2929 2930 void 2931 bpfdetach(struct ifnet *ifp) 2932 { 2933 } 2934 2935 u_int 2936 bpf_filter(const struct bpf_insn *pc, u_char *p, u_int wirelen, u_int buflen) 2937 { 2938 return -1; /* "no filter" behaviour */ 2939 } 2940 2941 int 2942 bpf_validate(const struct bpf_insn *f, int len) 2943 { 2944 return 0; /* false */ 2945 } 2946 2947 #endif /* !DEV_BPF && !NETGRAPH_BPF */ 2948