bpf.c revision 1.258
1 /* $NetBSD: bpf.c,v 1.258 2024/10/20 14:03:51 mlelstv Exp $ */ 2 3 /* 4 * Copyright (c) 1990, 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from the Stanford/CMU enet packet filter, 8 * (net/enet.c) distributed as part of 4.3BSD, and code contributed 9 * to Berkeley by Steven McCanne and Van Jacobson both of Lawrence 10 * Berkeley Laboratory. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)bpf.c 8.4 (Berkeley) 1/9/95 37 * static char rcsid[] = 38 * "Header: bpf.c,v 1.67 96/09/26 22:00:52 leres Exp "; 39 */ 40 41 #include <sys/cdefs.h> 42 __KERNEL_RCSID(0, "$NetBSD: bpf.c,v 1.258 2024/10/20 14:03:51 mlelstv Exp $"); 43 44 #if defined(_KERNEL_OPT) 45 #include "opt_bpf.h" 46 #include "sl.h" 47 #include "opt_net_mpsafe.h" 48 #endif 49 50 #include <sys/param.h> 51 52 #include <sys/atomic.h> 53 #include <sys/buf.h> 54 #include <sys/conf.h> 55 #include <sys/cpu.h> 56 #include <sys/errno.h> 57 #include <sys/file.h> 58 #include <sys/filedesc.h> 59 #include <sys/ioctl.h> 60 #include <sys/kauth.h> 61 #include <sys/kernel.h> 62 #include <sys/lwp.h> 63 #include <sys/mbuf.h> 64 #include <sys/module.h> 65 #include <sys/percpu.h> 66 #include <sys/poll.h> 67 #include <sys/proc.h> 68 #include <sys/protosw.h> 69 #include <sys/pserialize.h> 70 #include <sys/queue.h> 71 #include <sys/socket.h> 72 #include <sys/stat.h> 73 #include <sys/sysctl.h> 74 #include <sys/syslog.h> 75 #include <sys/systm.h> 76 #include <sys/time.h> 77 #include <sys/tty.h> 78 #include <sys/uio.h> 79 #include <sys/vnode.h> 80 #include <sys/xcall.h> 81 82 #include <net/bpf.h> 83 #include <net/bpfdesc.h> 84 #include <net/bpfjit.h> 85 #include <net/if.h> 86 #include <net/if_arc.h> 87 #include <net/if_ether.h> 88 #include <net/if_types.h> 89 #include <net/slip.h> 90 91 #include <netinet/if_inarp.h> 92 #include <netinet/in.h> 93 94 #include <compat/sys/sockio.h> 95 96 #ifndef BPF_BUFSIZE 97 /* 98 * 4096 is too small for FDDI frames. 8192 is too small for gigabit Ethernet 99 * jumbos (circa 9k), ATM, or Intel gig/10gig ethernet jumbos (16k). 100 */ 101 # define BPF_BUFSIZE 32768 102 #endif 103 104 #define PRINET 26 /* interruptible */ 105 106 /* 107 * The default read buffer size, and limit for BIOCSBLEN, is sysctl'able. 108 * XXX the default values should be computed dynamically based 109 * on available memory size and available mbuf clusters. 110 */ 111 static int bpf_bufsize = BPF_BUFSIZE; 112 static int bpf_maxbufsize = BPF_DFLTBUFSIZE; /* XXX set dynamically, see above */ 113 static bool bpf_jit = false; 114 115 struct bpfjit_ops bpfjit_module_ops = { 116 .bj_generate_code = NULL, 117 .bj_free_code = NULL 118 }; 119 120 /* 121 * Global BPF statistics returned by net.bpf.stats sysctl. 122 */ 123 static struct percpu *bpf_gstats_percpu; /* struct bpf_stat */ 124 125 #define BPF_STATINC(id) \ 126 { \ 127 struct bpf_stat *__stats = \ 128 percpu_getref(bpf_gstats_percpu); \ 129 __stats->bs_##id++; \ 130 percpu_putref(bpf_gstats_percpu); \ 131 } 132 133 /* 134 * Locking notes: 135 * - bpf_mtx (adaptive mutex) protects: 136 * - Gobal lists: bpf_iflist and bpf_dlist 137 * - struct bpf_if 138 * - bpf_close 139 * - bpf_psz (pserialize) 140 * - struct bpf_d has two mutexes: 141 * - bd_buf_mtx (spin mutex) protects the buffers that can be accessed 142 * on packet tapping 143 * - bd_mtx (adaptive mutex) protects member variables other than the buffers 144 * - Locking order: bpf_mtx => bpf_d#bd_mtx => bpf_d#bd_buf_mtx 145 * - struct bpf_d obtained via fp->f_bpf in bpf_read and bpf_write is 146 * never freed because struct bpf_d is only freed in bpf_close and 147 * bpf_close never be called while executing bpf_read and bpf_write 148 * - A filter that is assigned to bpf_d can be replaced with another filter 149 * while tapping packets, so it needs to be done atomically 150 * - struct bpf_d is iterated on bpf_dlist with psz 151 * - struct bpf_if is iterated on bpf_iflist with psz or psref 152 */ 153 /* 154 * Use a mutex to avoid a race condition between gathering the stats/peers 155 * and opening/closing the device. 156 */ 157 static kmutex_t bpf_mtx; 158 159 static struct psref_class *bpf_psref_class __read_mostly; 160 static pserialize_t bpf_psz; 161 162 static inline void 163 bpf_if_acquire(struct bpf_if *bp, struct psref *psref) 164 { 165 166 psref_acquire(psref, &bp->bif_psref, bpf_psref_class); 167 } 168 169 static inline void 170 bpf_if_release(struct bpf_if *bp, struct psref *psref) 171 { 172 173 psref_release(psref, &bp->bif_psref, bpf_psref_class); 174 } 175 176 /* 177 * bpf_iflist is the list of interfaces; each corresponds to an ifnet 178 * bpf_dtab holds the descriptors, indexed by minor device # 179 */ 180 static struct pslist_head bpf_iflist; 181 static struct pslist_head bpf_dlist; 182 183 /* Macros for bpf_d on bpf_dlist */ 184 #define BPF_DLIST_WRITER_INSERT_HEAD(__d) \ 185 PSLIST_WRITER_INSERT_HEAD(&bpf_dlist, (__d), bd_bpf_dlist_entry) 186 #define BPF_DLIST_READER_FOREACH(__d) \ 187 PSLIST_READER_FOREACH((__d), &bpf_dlist, struct bpf_d, \ 188 bd_bpf_dlist_entry) 189 #define BPF_DLIST_WRITER_FOREACH(__d) \ 190 PSLIST_WRITER_FOREACH((__d), &bpf_dlist, struct bpf_d, \ 191 bd_bpf_dlist_entry) 192 #define BPF_DLIST_ENTRY_INIT(__d) \ 193 PSLIST_ENTRY_INIT((__d), bd_bpf_dlist_entry) 194 #define BPF_DLIST_WRITER_REMOVE(__d) \ 195 PSLIST_WRITER_REMOVE((__d), bd_bpf_dlist_entry) 196 #define BPF_DLIST_ENTRY_DESTROY(__d) \ 197 PSLIST_ENTRY_DESTROY((__d), bd_bpf_dlist_entry) 198 199 /* Macros for bpf_if on bpf_iflist */ 200 #define BPF_IFLIST_WRITER_INSERT_HEAD(__bp) \ 201 PSLIST_WRITER_INSERT_HEAD(&bpf_iflist, (__bp), bif_iflist_entry) 202 #define BPF_IFLIST_READER_FOREACH(__bp) \ 203 PSLIST_READER_FOREACH((__bp), &bpf_iflist, struct bpf_if, \ 204 bif_iflist_entry) 205 #define BPF_IFLIST_WRITER_FOREACH(__bp) \ 206 PSLIST_WRITER_FOREACH((__bp), &bpf_iflist, struct bpf_if, \ 207 bif_iflist_entry) 208 #define BPF_IFLIST_WRITER_REMOVE(__bp) \ 209 PSLIST_WRITER_REMOVE((__bp), bif_iflist_entry) 210 #define BPF_IFLIST_ENTRY_INIT(__bp) \ 211 PSLIST_ENTRY_INIT((__bp), bif_iflist_entry) 212 #define BPF_IFLIST_ENTRY_DESTROY(__bp) \ 213 PSLIST_ENTRY_DESTROY((__bp), bif_iflist_entry) 214 215 /* Macros for bpf_d on bpf_if#bif_dlist_pslist */ 216 #define BPFIF_DLIST_READER_FOREACH(__d, __bp) \ 217 PSLIST_READER_FOREACH((__d), &(__bp)->bif_dlist_head, struct bpf_d, \ 218 bd_bif_dlist_entry) 219 #define BPFIF_DLIST_WRITER_INSERT_HEAD(__bp, __d) \ 220 PSLIST_WRITER_INSERT_HEAD(&(__bp)->bif_dlist_head, (__d), \ 221 bd_bif_dlist_entry) 222 #define BPFIF_DLIST_WRITER_REMOVE(__d) \ 223 PSLIST_WRITER_REMOVE((__d), bd_bif_dlist_entry) 224 #define BPFIF_DLIST_ENTRY_INIT(__d) \ 225 PSLIST_ENTRY_INIT((__d), bd_bif_dlist_entry) 226 #define BPFIF_DLIST_READER_EMPTY(__bp) \ 227 (PSLIST_READER_FIRST(&(__bp)->bif_dlist_head, struct bpf_d, \ 228 bd_bif_dlist_entry) == NULL) 229 #define BPFIF_DLIST_WRITER_EMPTY(__bp) \ 230 (PSLIST_WRITER_FIRST(&(__bp)->bif_dlist_head, struct bpf_d, \ 231 bd_bif_dlist_entry) == NULL) 232 #define BPFIF_DLIST_ENTRY_DESTROY(__d) \ 233 PSLIST_ENTRY_DESTROY((__d), bd_bif_dlist_entry) 234 235 static int bpf_allocbufs(struct bpf_d *); 236 static u_int bpf_xfilter(struct bpf_filter **, void *, u_int, u_int); 237 static void bpf_deliver(struct bpf_if *, 238 void *(*cpfn)(void *, const void *, size_t), 239 void *, u_int, u_int, const u_int); 240 static void bpf_freed(struct bpf_d *); 241 static void bpf_free_filter(struct bpf_filter *); 242 static void bpf_ifname(struct ifnet *, struct ifreq *); 243 static void *bpf_mcpy(void *, const void *, size_t); 244 static int bpf_movein(struct ifnet *, struct uio *, int, uint64_t, 245 struct mbuf **, struct sockaddr *, 246 struct bpf_filter **); 247 static void bpf_attachd(struct bpf_d *, struct bpf_if *); 248 static void bpf_detachd(struct bpf_d *); 249 static int bpf_setif(struct bpf_d *, struct ifreq *); 250 static int bpf_setf(struct bpf_d *, struct bpf_program *, u_long); 251 static void bpf_timed_out(void *); 252 static inline void 253 bpf_wakeup(struct bpf_d *); 254 static int bpf_hdrlen(struct bpf_d *); 255 static void catchpacket(struct bpf_d *, u_char *, u_int, u_int, 256 void *(*)(void *, const void *, size_t), 257 struct timespec *); 258 static void reset_d(struct bpf_d *); 259 static int bpf_getdltlist(struct bpf_d *, struct bpf_dltlist *); 260 static int bpf_setdlt(struct bpf_d *, u_int); 261 262 static int bpf_read(struct file *, off_t *, struct uio *, kauth_cred_t, 263 int); 264 static int bpf_write(struct file *, off_t *, struct uio *, kauth_cred_t, 265 int); 266 static int bpf_ioctl(struct file *, u_long, void *); 267 static int bpf_poll(struct file *, int); 268 static int bpf_stat(struct file *, struct stat *); 269 static int bpf_close(struct file *); 270 static int bpf_kqfilter(struct file *, struct knote *); 271 static void bpf_softintr(void *); 272 273 static const struct fileops bpf_fileops = { 274 .fo_name = "bpf", 275 .fo_read = bpf_read, 276 .fo_write = bpf_write, 277 .fo_ioctl = bpf_ioctl, 278 .fo_fcntl = fnullop_fcntl, 279 .fo_poll = bpf_poll, 280 .fo_stat = bpf_stat, 281 .fo_close = bpf_close, 282 .fo_kqfilter = bpf_kqfilter, 283 .fo_restart = fnullop_restart, 284 }; 285 286 dev_type_open(bpfopen); 287 288 const struct cdevsw bpf_cdevsw = { 289 .d_open = bpfopen, 290 .d_close = noclose, 291 .d_read = noread, 292 .d_write = nowrite, 293 .d_ioctl = noioctl, 294 .d_stop = nostop, 295 .d_tty = notty, 296 .d_poll = nopoll, 297 .d_mmap = nommap, 298 .d_kqfilter = nokqfilter, 299 .d_discard = nodiscard, 300 .d_flag = D_OTHER | D_MPSAFE 301 }; 302 303 bpfjit_func_t 304 bpf_jit_generate(bpf_ctx_t *bc, void *code, size_t size) 305 { 306 struct bpfjit_ops *ops = &bpfjit_module_ops; 307 bpfjit_func_t (*generate_code)(const bpf_ctx_t *, 308 const struct bpf_insn *, size_t); 309 310 generate_code = atomic_load_acquire(&ops->bj_generate_code); 311 if (generate_code != NULL) { 312 return generate_code(bc, code, size); 313 } 314 return NULL; 315 } 316 317 void 318 bpf_jit_freecode(bpfjit_func_t jcode) 319 { 320 KASSERT(bpfjit_module_ops.bj_free_code != NULL); 321 bpfjit_module_ops.bj_free_code(jcode); 322 } 323 324 static int 325 bpf_movein(struct ifnet *ifp, struct uio *uio, int linktype, uint64_t mtu, 326 struct mbuf **mp, struct sockaddr *sockp, struct bpf_filter **wfilter) 327 { 328 struct mbuf *m, *m0, *n; 329 int error; 330 size_t len; 331 size_t hlen; 332 size_t align; 333 u_int slen; 334 335 /* 336 * Build a sockaddr based on the data link layer type. 337 * We do this at this level because the ethernet header 338 * is copied directly into the data field of the sockaddr. 339 * In the case of SLIP, there is no header and the packet 340 * is forwarded as is. 341 * Also, we are careful to leave room at the front of the mbuf 342 * for the link level header. 343 */ 344 switch (linktype) { 345 346 case DLT_SLIP: 347 sockp->sa_family = AF_INET; 348 hlen = 0; 349 align = 0; 350 break; 351 352 case DLT_PPP: 353 sockp->sa_family = AF_UNSPEC; 354 hlen = 0; 355 align = 0; 356 break; 357 358 case DLT_EN10MB: 359 sockp->sa_family = AF_UNSPEC; 360 /* XXX Would MAXLINKHDR be better? */ 361 /* 6(dst)+6(src)+2(type) */ 362 hlen = sizeof(struct ether_header); 363 align = 2; 364 break; 365 366 case DLT_ARCNET: 367 sockp->sa_family = AF_UNSPEC; 368 hlen = ARC_HDRLEN; 369 align = 5; 370 break; 371 372 case DLT_FDDI: 373 sockp->sa_family = AF_LINK; 374 /* XXX 4(FORMAC)+6(dst)+6(src) */ 375 hlen = 16; 376 align = 0; 377 break; 378 379 case DLT_ECONET: 380 sockp->sa_family = AF_UNSPEC; 381 hlen = 6; 382 align = 2; 383 break; 384 385 case DLT_NULL: 386 sockp->sa_family = AF_UNSPEC; 387 if (ifp->if_type == IFT_LOOP) { 388 /* Set here to apply the following validations */ 389 hlen = sizeof(uint32_t); 390 } else 391 hlen = 0; 392 align = 0; 393 break; 394 395 default: 396 return (EIO); 397 } 398 399 len = uio->uio_resid; 400 /* 401 * If there aren't enough bytes for a link level header or the 402 * packet length exceeds the interface mtu, return an error. 403 */ 404 if (len - hlen > mtu) 405 return (EMSGSIZE); 406 407 m0 = m = m_gethdr(M_WAIT, MT_DATA); 408 m_reset_rcvif(m); 409 m->m_pkthdr.len = (int)(len - hlen); 410 if (len + align > MHLEN) { 411 m_clget(m, M_WAIT); 412 if ((m->m_flags & M_EXT) == 0) { 413 error = ENOBUFS; 414 goto bad; 415 } 416 } 417 418 /* Ensure the data is properly aligned */ 419 if (align > 0) 420 m->m_data += align; 421 422 for (;;) { 423 len = M_TRAILINGSPACE(m); 424 if (len > uio->uio_resid) 425 len = uio->uio_resid; 426 error = uiomove(mtod(m, void *), len, uio); 427 if (error) 428 goto bad; 429 m->m_len = len; 430 431 if (uio->uio_resid == 0) 432 break; 433 434 n = m_get(M_WAIT, MT_DATA); 435 m_clget(n, M_WAIT); /* if fails, there is no problem */ 436 m->m_next = n; 437 m = n; 438 } 439 440 slen = bpf_xfilter(wfilter, mtod(m, u_char *), len, len); 441 if (slen == 0) { 442 error = EPERM; 443 goto bad; 444 } 445 446 if (hlen != 0) { 447 if (linktype == DLT_NULL && ifp->if_type == IFT_LOOP) { 448 uint32_t af; 449 /* the link header indicates the address family */ 450 memcpy(&af, mtod(m0, void *), sizeof(af)); 451 sockp->sa_family = af; 452 } else { 453 /* move link level header in the top of mbuf to sa_data */ 454 memcpy(sockp->sa_data, mtod(m0, void *), hlen); 455 } 456 m0->m_data += hlen; 457 m0->m_len -= hlen; 458 } 459 460 m_claimm(m, ifp->if_mowner); 461 462 *mp = m0; 463 return (0); 464 465 bad: 466 m_freem(m0); 467 return (error); 468 } 469 470 /* 471 * Attach file to the bpf interface, i.e. make d listen on bp. 472 */ 473 static void 474 bpf_attachd(struct bpf_d *d, struct bpf_if *bp) 475 { 476 struct bpf_event_tracker *t; 477 478 KASSERT(mutex_owned(&bpf_mtx)); 479 KASSERT(mutex_owned(d->bd_mtx)); 480 /* 481 * Point d at bp, and add d to the interface's list of listeners. 482 * Finally, point the driver's bpf cookie at the interface so 483 * it will divert packets to bpf. 484 */ 485 d->bd_bif = bp; 486 BPFIF_DLIST_WRITER_INSERT_HEAD(bp, d); 487 488 *bp->bif_driverp = bp; 489 490 SLIST_FOREACH(t, &bp->bif_trackers, bet_entries) { 491 t->bet_notify(bp, bp->bif_ifp, bp->bif_dlt, 492 BPF_TRACK_EVENT_ATTACH); 493 } 494 } 495 496 /* 497 * Detach a file from its interface. 498 */ 499 static void 500 bpf_detachd(struct bpf_d *d) 501 { 502 struct bpf_if *bp; 503 struct bpf_event_tracker *t; 504 505 KASSERT(mutex_owned(&bpf_mtx)); 506 KASSERT(mutex_owned(d->bd_mtx)); 507 508 bp = d->bd_bif; 509 /* 510 * Check if this descriptor had requested promiscuous mode. 511 * If so, turn it off. 512 */ 513 if (d->bd_promisc) { 514 int error __diagused; 515 516 d->bd_promisc = 0; 517 /* 518 * Take device out of promiscuous mode. Since we were 519 * able to enter promiscuous mode, we should be able 520 * to turn it off. But we can get an error if 521 * the interface was configured down, so only panic 522 * if we don't get an unexpected error. 523 */ 524 KERNEL_LOCK_UNLESS_NET_MPSAFE(); 525 error = ifpromisc(bp->bif_ifp, 0); 526 KERNEL_UNLOCK_UNLESS_NET_MPSAFE(); 527 #ifdef DIAGNOSTIC 528 if (error) 529 printf("%s: ifpromisc failed: %d", __func__, error); 530 #endif 531 } 532 533 /* Remove d from the interface's descriptor list. */ 534 BPFIF_DLIST_WRITER_REMOVE(d); 535 536 pserialize_perform(bpf_psz); 537 538 if (BPFIF_DLIST_WRITER_EMPTY(bp)) { 539 /* 540 * Let the driver know that there are no more listeners. 541 */ 542 *d->bd_bif->bif_driverp = NULL; 543 } 544 545 d->bd_bif = NULL; 546 547 SLIST_FOREACH(t, &bp->bif_trackers, bet_entries) { 548 t->bet_notify(bp, bp->bif_ifp, bp->bif_dlt, 549 BPF_TRACK_EVENT_DETACH); 550 } 551 } 552 553 static void 554 bpf_init(void) 555 { 556 557 mutex_init(&bpf_mtx, MUTEX_DEFAULT, IPL_NONE); 558 bpf_psz = pserialize_create(); 559 bpf_psref_class = psref_class_create("bpf", IPL_SOFTNET); 560 561 PSLIST_INIT(&bpf_iflist); 562 PSLIST_INIT(&bpf_dlist); 563 564 bpf_gstats_percpu = percpu_alloc(sizeof(struct bpf_stat)); 565 566 return; 567 } 568 569 /* 570 * bpfilterattach() is called at boot time. We don't need to do anything 571 * here, since any initialization will happen as part of module init code. 572 */ 573 /* ARGSUSED */ 574 void 575 bpfilterattach(int n) 576 { 577 578 } 579 580 /* 581 * Open ethernet device. Clones. 582 */ 583 /* ARGSUSED */ 584 int 585 bpfopen(dev_t dev, int flag, int mode, struct lwp *l) 586 { 587 struct bpf_d *d; 588 struct file *fp; 589 int error, fd; 590 591 /* falloc() will fill in the descriptor for us. */ 592 if ((error = fd_allocfile(&fp, &fd)) != 0) 593 return error; 594 595 d = kmem_zalloc(sizeof(*d), KM_SLEEP); 596 d->bd_bufsize = bpf_bufsize; 597 d->bd_direction = BPF_D_INOUT; 598 d->bd_feedback = 0; 599 d->bd_pid = l->l_proc->p_pid; 600 #ifdef _LP64 601 if (curproc->p_flag & PK_32) 602 d->bd_compat32 = 1; 603 #endif 604 getnanotime(&d->bd_btime); 605 d->bd_atime = d->bd_mtime = d->bd_btime; 606 callout_init(&d->bd_callout, CALLOUT_MPSAFE); 607 selinit(&d->bd_sel); 608 d->bd_sih = softint_establish(SOFTINT_CLOCK, bpf_softintr, d); 609 d->bd_jitcode = NULL; 610 d->bd_rfilter = NULL; 611 d->bd_wfilter = NULL; 612 d->bd_locked = 0; 613 BPF_DLIST_ENTRY_INIT(d); 614 BPFIF_DLIST_ENTRY_INIT(d); 615 d->bd_mtx = mutex_obj_alloc(MUTEX_DEFAULT, IPL_SOFTNET); 616 d->bd_buf_mtx = mutex_obj_alloc(MUTEX_DEFAULT, IPL_NET); 617 cv_init(&d->bd_cv, "bpf"); 618 619 mutex_enter(&bpf_mtx); 620 BPF_DLIST_WRITER_INSERT_HEAD(d); 621 mutex_exit(&bpf_mtx); 622 623 return fd_clone(fp, fd, flag, &bpf_fileops, d); 624 } 625 626 /* 627 * Close the descriptor by detaching it from its interface, 628 * deallocating its buffers, and marking it free. 629 */ 630 /* ARGSUSED */ 631 static int 632 bpf_close(struct file *fp) 633 { 634 struct bpf_d *d; 635 636 mutex_enter(&bpf_mtx); 637 638 if ((d = fp->f_bpf) == NULL) { 639 mutex_exit(&bpf_mtx); 640 return 0; 641 } 642 643 /* 644 * Refresh the PID associated with this bpf file. 645 */ 646 d->bd_pid = curproc->p_pid; 647 648 mutex_enter(d->bd_buf_mtx); 649 if (d->bd_state == BPF_WAITING) 650 callout_halt(&d->bd_callout, d->bd_buf_mtx); 651 d->bd_state = BPF_IDLE; 652 mutex_exit(d->bd_buf_mtx); 653 mutex_enter(d->bd_mtx); 654 if (d->bd_bif) 655 bpf_detachd(d); 656 mutex_exit(d->bd_mtx); 657 658 BPF_DLIST_WRITER_REMOVE(d); 659 660 pserialize_perform(bpf_psz); 661 mutex_exit(&bpf_mtx); 662 663 BPFIF_DLIST_ENTRY_DESTROY(d); 664 BPF_DLIST_ENTRY_DESTROY(d); 665 fp->f_bpf = NULL; 666 bpf_freed(d); 667 callout_destroy(&d->bd_callout); 668 seldestroy(&d->bd_sel); 669 softint_disestablish(d->bd_sih); 670 mutex_obj_free(d->bd_mtx); 671 mutex_obj_free(d->bd_buf_mtx); 672 cv_destroy(&d->bd_cv); 673 674 kmem_free(d, sizeof(*d)); 675 676 return (0); 677 } 678 679 /* 680 * Rotate the packet buffers in descriptor d. Move the store buffer 681 * into the hold slot, and the free buffer into the store slot. 682 * Zero the length of the new store buffer. 683 */ 684 #define ROTATE_BUFFERS(d) \ 685 (d)->bd_hbuf = (d)->bd_sbuf; \ 686 (d)->bd_hlen = (d)->bd_slen; \ 687 (d)->bd_sbuf = (d)->bd_fbuf; \ 688 (d)->bd_slen = 0; \ 689 (d)->bd_fbuf = NULL; 690 /* 691 * bpfread - read next chunk of packets from buffers 692 */ 693 static int 694 bpf_read(struct file *fp, off_t *offp, struct uio *uio, 695 kauth_cred_t cred, int flags) 696 { 697 struct bpf_d *d = fp->f_bpf; 698 int timed_out; 699 int error; 700 701 /* 702 * Refresh the PID associated with this bpf file. 703 */ 704 d->bd_pid = curproc->p_pid; 705 706 getnanotime(&d->bd_atime); 707 /* 708 * Restrict application to use a buffer the same size as 709 * the kernel buffers. 710 */ 711 if (uio->uio_resid != d->bd_bufsize) 712 return (EINVAL); 713 714 mutex_enter(d->bd_buf_mtx); 715 if (d->bd_state == BPF_WAITING) 716 callout_halt(&d->bd_callout, d->bd_buf_mtx); 717 timed_out = (d->bd_state == BPF_TIMED_OUT); 718 d->bd_state = BPF_IDLE; 719 mutex_exit(d->bd_buf_mtx); 720 /* 721 * If the hold buffer is empty, then do a timed sleep, which 722 * ends when the timeout expires or when enough packets 723 * have arrived to fill the store buffer. 724 */ 725 mutex_enter(d->bd_buf_mtx); 726 while (d->bd_hbuf == NULL) { 727 if (fp->f_flag & FNONBLOCK) { 728 if (d->bd_slen == 0) { 729 error = EWOULDBLOCK; 730 goto out; 731 } 732 ROTATE_BUFFERS(d); 733 break; 734 } 735 736 if ((d->bd_immediate || timed_out) && d->bd_slen != 0) { 737 /* 738 * A packet(s) either arrived since the previous 739 * read or arrived while we were asleep. 740 * Rotate the buffers and return what's here. 741 */ 742 ROTATE_BUFFERS(d); 743 break; 744 } 745 746 error = cv_timedwait_sig(&d->bd_cv, d->bd_buf_mtx, d->bd_rtout); 747 748 if (error == EINTR || error == ERESTART) 749 goto out; 750 751 if (error == EWOULDBLOCK) { 752 /* 753 * On a timeout, return what's in the buffer, 754 * which may be nothing. If there is something 755 * in the store buffer, we can rotate the buffers. 756 */ 757 if (d->bd_hbuf) 758 /* 759 * We filled up the buffer in between 760 * getting the timeout and arriving 761 * here, so we don't need to rotate. 762 */ 763 break; 764 765 if (d->bd_slen == 0) { 766 error = 0; 767 goto out; 768 } 769 ROTATE_BUFFERS(d); 770 break; 771 } 772 if (error != 0) 773 goto out; 774 } 775 /* 776 * At this point, we know we have something in the hold slot. 777 */ 778 mutex_exit(d->bd_buf_mtx); 779 780 /* 781 * Move data from hold buffer into user space. 782 * We know the entire buffer is transferred since 783 * we checked above that the read buffer is bpf_bufsize bytes. 784 */ 785 error = uiomove(d->bd_hbuf, d->bd_hlen, uio); 786 787 mutex_enter(d->bd_buf_mtx); 788 d->bd_fbuf = d->bd_hbuf; 789 d->bd_hbuf = NULL; 790 d->bd_hlen = 0; 791 out: 792 mutex_exit(d->bd_buf_mtx); 793 return (error); 794 } 795 796 /* 797 * If there are processes sleeping on this descriptor, wake them up. 798 */ 799 static inline void 800 bpf_wakeup(struct bpf_d *d) 801 { 802 803 KASSERT(mutex_owned(d->bd_buf_mtx)); 804 805 cv_broadcast(&d->bd_cv); 806 807 if (d->bd_async) 808 softint_schedule(d->bd_sih); 809 selnotify(&d->bd_sel, 0, NOTE_SUBMIT); 810 } 811 812 static void 813 bpf_softintr(void *cookie) 814 { 815 struct bpf_d *d; 816 817 d = cookie; 818 if (d->bd_async) 819 fownsignal(d->bd_pgid, SIGIO, 0, 0, NULL); 820 } 821 822 static void 823 bpf_timed_out(void *arg) 824 { 825 struct bpf_d *d = arg; 826 827 mutex_enter(d->bd_buf_mtx); 828 if (d->bd_state == BPF_WAITING) { 829 d->bd_state = BPF_TIMED_OUT; 830 if (d->bd_slen != 0) 831 bpf_wakeup(d); 832 } 833 mutex_exit(d->bd_buf_mtx); 834 } 835 836 static int 837 bpf_write(struct file *fp, off_t *offp, struct uio *uio, 838 kauth_cred_t cred, int flags) 839 { 840 struct bpf_d *d = fp->f_bpf; 841 struct bpf_if *bp; 842 struct ifnet *ifp; 843 struct mbuf *m, *mc; 844 int error; 845 static struct sockaddr_storage dst; 846 struct psref psref; 847 int bound; 848 849 /* 850 * Refresh the PID associated with this bpf file. 851 */ 852 d->bd_pid = curproc->p_pid; 853 854 m = NULL; /* XXX gcc */ 855 856 bound = curlwp_bind(); 857 mutex_enter(d->bd_mtx); 858 bp = d->bd_bif; 859 if (bp == NULL) { 860 mutex_exit(d->bd_mtx); 861 error = ENXIO; 862 goto out_bindx; 863 } 864 bpf_if_acquire(bp, &psref); 865 mutex_exit(d->bd_mtx); 866 867 getnanotime(&d->bd_mtime); 868 869 ifp = bp->bif_ifp; 870 if (if_is_deactivated(ifp)) { 871 error = ENXIO; 872 goto out; 873 } 874 875 if (uio->uio_resid == 0) { 876 error = 0; 877 goto out; 878 } 879 880 error = bpf_movein(ifp, uio, (int)bp->bif_dlt, ifp->if_mtu, &m, 881 (struct sockaddr *) &dst, &d->bd_wfilter); 882 if (error) 883 goto out; 884 885 if (m->m_pkthdr.len > ifp->if_mtu) { 886 m_freem(m); 887 error = EMSGSIZE; 888 goto out; 889 } 890 891 /* 892 * If writing to a loopback interface, the address family has 893 * already been specially computed in bpf_movein(), so don't 894 * clobber it, or the loopback will reject it in looutput(). 895 */ 896 if (d->bd_hdrcmplt && ifp->if_type != IFT_LOOP) 897 dst.ss_family = pseudo_AF_HDRCMPLT; 898 899 if (d->bd_feedback) { 900 mc = m_dup(m, 0, M_COPYALL, M_NOWAIT); 901 if (mc != NULL) 902 m_set_rcvif(mc, ifp); 903 /* Set M_PROMISC for outgoing packets to be discarded. */ 904 if (1 /*d->bd_direction == BPF_D_INOUT*/) 905 m->m_flags |= M_PROMISC; 906 } else 907 mc = NULL; 908 909 error = if_output_lock(ifp, ifp, m, (struct sockaddr *) &dst, NULL); 910 911 if (mc != NULL) { 912 if (error == 0) { 913 int s = splsoftnet(); 914 KERNEL_LOCK_UNLESS_IFP_MPSAFE(ifp); 915 ifp->_if_input(ifp, mc); 916 KERNEL_UNLOCK_UNLESS_IFP_MPSAFE(ifp); 917 splx(s); 918 } else 919 m_freem(mc); 920 } 921 /* 922 * The driver frees the mbuf. 923 */ 924 out: 925 bpf_if_release(bp, &psref); 926 out_bindx: 927 curlwp_bindx(bound); 928 return error; 929 } 930 931 /* 932 * Reset a descriptor by flushing its packet buffer and clearing the 933 * receive and drop counts. 934 */ 935 static void 936 reset_d(struct bpf_d *d) 937 { 938 939 KASSERT(mutex_owned(d->bd_mtx)); 940 941 mutex_enter(d->bd_buf_mtx); 942 if (d->bd_hbuf) { 943 /* Free the hold buffer. */ 944 d->bd_fbuf = d->bd_hbuf; 945 d->bd_hbuf = NULL; 946 } 947 d->bd_slen = 0; 948 d->bd_hlen = 0; 949 d->bd_rcount = 0; 950 d->bd_dcount = 0; 951 d->bd_ccount = 0; 952 mutex_exit(d->bd_buf_mtx); 953 } 954 955 /* 956 * FIONREAD Check for read packet available. 957 * BIOCGBLEN Get buffer len [for read()]. 958 * BIOCSETF Set ethernet read filter. 959 * BIOCFLUSH Flush read packet buffer. 960 * BIOCPROMISC Put interface into promiscuous mode. 961 * BIOCGDLT Get link layer type. 962 * BIOCGETIF Get interface name. 963 * BIOCSETIF Set interface. 964 * BIOCSRTIMEOUT Set read timeout. 965 * BIOCGRTIMEOUT Get read timeout. 966 * BIOCGSTATS Get packet stats. 967 * BIOCIMMEDIATE Set immediate mode. 968 * BIOCVERSION Get filter language version. 969 * BIOCGHDRCMPLT Get "header already complete" flag. 970 * BIOCSHDRCMPLT Set "header already complete" flag. 971 * BIOCSFEEDBACK Set packet feedback mode. 972 * BIOCGFEEDBACK Get packet feedback mode. 973 * BIOCGDIRECTION Get packet direction flag 974 * BIOCSDIRECTION Set packet direction flag 975 */ 976 /* ARGSUSED */ 977 static int 978 bpf_ioctl(struct file *fp, u_long cmd, void *addr) 979 { 980 struct bpf_d *d = fp->f_bpf; 981 int error = 0; 982 983 /* 984 * Refresh the PID associated with this bpf file. 985 */ 986 d->bd_pid = curproc->p_pid; 987 #ifdef _LP64 988 if (curproc->p_flag & PK_32) 989 d->bd_compat32 = 1; 990 else 991 d->bd_compat32 = 0; 992 #endif 993 994 mutex_enter(d->bd_buf_mtx); 995 if (d->bd_state == BPF_WAITING) 996 callout_halt(&d->bd_callout, d->bd_buf_mtx); 997 d->bd_state = BPF_IDLE; 998 mutex_exit(d->bd_buf_mtx); 999 1000 if (d->bd_locked) { 1001 switch (cmd) { 1002 case BIOCGBLEN: /* FALLTHROUGH */ 1003 case BIOCFLUSH: /* FALLTHROUGH */ 1004 case BIOCGDLT: /* FALLTHROUGH */ 1005 case BIOCGDLTLIST: /* FALLTHROUGH */ 1006 case BIOCGETIF: /* FALLTHROUGH */ 1007 case BIOCGRTIMEOUT: /* FALLTHROUGH */ 1008 case BIOCGSTATS: /* FALLTHROUGH */ 1009 case BIOCVERSION: /* FALLTHROUGH */ 1010 case BIOCGHDRCMPLT: /* FALLTHROUGH */ 1011 case FIONREAD: /* FALLTHROUGH */ 1012 case BIOCLOCK: /* FALLTHROUGH */ 1013 case BIOCSRTIMEOUT: /* FALLTHROUGH */ 1014 case BIOCIMMEDIATE: /* FALLTHROUGH */ 1015 case TIOCGPGRP: 1016 break; 1017 default: 1018 return EPERM; 1019 } 1020 } 1021 1022 switch (cmd) { 1023 1024 default: 1025 error = EINVAL; 1026 break; 1027 1028 /* 1029 * Check for read packet available. 1030 */ 1031 case FIONREAD: { 1032 int n; 1033 1034 mutex_enter(d->bd_buf_mtx); 1035 n = d->bd_slen; 1036 if (d->bd_hbuf) 1037 n += d->bd_hlen; 1038 mutex_exit(d->bd_buf_mtx); 1039 1040 *(int *)addr = n; 1041 break; 1042 } 1043 1044 /* 1045 * Get buffer len [for read()]. 1046 */ 1047 case BIOCGBLEN: 1048 *(u_int *)addr = d->bd_bufsize; 1049 break; 1050 1051 /* 1052 * Set buffer length. 1053 */ 1054 case BIOCSBLEN: 1055 /* 1056 * Forbid to change the buffer length if buffers are already 1057 * allocated. 1058 */ 1059 mutex_enter(d->bd_mtx); 1060 mutex_enter(d->bd_buf_mtx); 1061 if (d->bd_bif != NULL || d->bd_sbuf != NULL) 1062 error = EINVAL; 1063 else { 1064 u_int size = *(u_int *)addr; 1065 1066 if (size > bpf_maxbufsize) 1067 *(u_int *)addr = size = bpf_maxbufsize; 1068 else if (size < BPF_MINBUFSIZE) 1069 *(u_int *)addr = size = BPF_MINBUFSIZE; 1070 d->bd_bufsize = size; 1071 } 1072 mutex_exit(d->bd_buf_mtx); 1073 mutex_exit(d->bd_mtx); 1074 break; 1075 1076 /* 1077 * Set link layer read filter. 1078 */ 1079 case BIOCSETF: /* FALLTHROUGH */ 1080 case BIOCSETWF: 1081 error = bpf_setf(d, addr, cmd); 1082 break; 1083 1084 case BIOCLOCK: 1085 d->bd_locked = 1; 1086 break; 1087 1088 /* 1089 * Flush read packet buffer. 1090 */ 1091 case BIOCFLUSH: 1092 mutex_enter(d->bd_mtx); 1093 reset_d(d); 1094 mutex_exit(d->bd_mtx); 1095 break; 1096 1097 /* 1098 * Put interface into promiscuous mode. 1099 */ 1100 case BIOCPROMISC: 1101 mutex_enter(d->bd_mtx); 1102 if (d->bd_bif == NULL) { 1103 mutex_exit(d->bd_mtx); 1104 /* 1105 * No interface attached yet. 1106 */ 1107 error = EINVAL; 1108 break; 1109 } 1110 if (d->bd_promisc == 0) { 1111 KERNEL_LOCK_UNLESS_NET_MPSAFE(); 1112 error = ifpromisc(d->bd_bif->bif_ifp, 1); 1113 KERNEL_UNLOCK_UNLESS_NET_MPSAFE(); 1114 if (error == 0) 1115 d->bd_promisc = 1; 1116 } 1117 mutex_exit(d->bd_mtx); 1118 break; 1119 1120 /* 1121 * Get device parameters. 1122 */ 1123 case BIOCGDLT: 1124 mutex_enter(d->bd_mtx); 1125 if (d->bd_bif == NULL) 1126 error = EINVAL; 1127 else 1128 *(u_int *)addr = d->bd_bif->bif_dlt; 1129 mutex_exit(d->bd_mtx); 1130 break; 1131 1132 /* 1133 * Get a list of supported device parameters. 1134 */ 1135 case BIOCGDLTLIST: 1136 mutex_enter(d->bd_mtx); 1137 if (d->bd_bif == NULL) 1138 error = EINVAL; 1139 else 1140 error = bpf_getdltlist(d, addr); 1141 mutex_exit(d->bd_mtx); 1142 break; 1143 1144 /* 1145 * Set device parameters. 1146 */ 1147 case BIOCSDLT: 1148 mutex_enter(&bpf_mtx); 1149 mutex_enter(d->bd_mtx); 1150 if (d->bd_bif == NULL) 1151 error = EINVAL; 1152 else 1153 error = bpf_setdlt(d, *(u_int *)addr); 1154 mutex_exit(d->bd_mtx); 1155 mutex_exit(&bpf_mtx); 1156 break; 1157 1158 /* 1159 * Set interface name. 1160 */ 1161 #ifdef OBIOCGETIF 1162 case OBIOCGETIF: 1163 #endif 1164 case BIOCGETIF: 1165 mutex_enter(d->bd_mtx); 1166 if (d->bd_bif == NULL) 1167 error = EINVAL; 1168 else 1169 bpf_ifname(d->bd_bif->bif_ifp, addr); 1170 mutex_exit(d->bd_mtx); 1171 break; 1172 1173 /* 1174 * Set interface. 1175 */ 1176 #ifdef OBIOCSETIF 1177 case OBIOCSETIF: 1178 #endif 1179 case BIOCSETIF: 1180 mutex_enter(&bpf_mtx); 1181 error = bpf_setif(d, addr); 1182 mutex_exit(&bpf_mtx); 1183 break; 1184 1185 /* 1186 * Set read timeout. 1187 */ 1188 case BIOCSRTIMEOUT: { 1189 struct timeval *tv = addr; 1190 1191 /* Compute number of ticks. */ 1192 if (tv->tv_sec < 0 || 1193 tv->tv_usec < 0 || tv->tv_usec >= 1000000) { 1194 error = EINVAL; 1195 break; 1196 } else if (tv->tv_sec > INT_MAX/hz - 1) { 1197 d->bd_rtout = INT_MAX; 1198 } else { 1199 d->bd_rtout = tv->tv_sec * hz + tv->tv_usec / tick; 1200 } 1201 if ((d->bd_rtout == 0) && (tv->tv_usec != 0)) 1202 d->bd_rtout = 1; 1203 break; 1204 } 1205 1206 #ifdef BIOCGORTIMEOUT 1207 /* 1208 * Get read timeout. 1209 */ 1210 case BIOCGORTIMEOUT: { 1211 struct timeval50 *tv = addr; 1212 1213 tv->tv_sec = d->bd_rtout / hz; 1214 tv->tv_usec = (d->bd_rtout % hz) * tick; 1215 break; 1216 } 1217 #endif 1218 1219 #ifdef BIOCSORTIMEOUT 1220 /* 1221 * Set read timeout. 1222 */ 1223 case BIOCSORTIMEOUT: { 1224 struct timeval50 *tv = addr; 1225 1226 /* Compute number of ticks. */ 1227 if (tv->tv_sec < 0 || 1228 tv->tv_usec < 0 || tv->tv_usec >= 1000000) { 1229 error = EINVAL; 1230 break; 1231 } else if (tv->tv_sec > INT_MAX/hz - 1) { 1232 d->bd_rtout = INT_MAX; 1233 } else { 1234 d->bd_rtout = tv->tv_sec * hz + tv->tv_usec / tick; 1235 } 1236 if ((d->bd_rtout == 0) && (tv->tv_usec != 0)) 1237 d->bd_rtout = 1; 1238 break; 1239 } 1240 #endif 1241 1242 /* 1243 * Get read timeout. 1244 */ 1245 case BIOCGRTIMEOUT: { 1246 struct timeval *tv = addr; 1247 1248 tv->tv_sec = d->bd_rtout / hz; 1249 tv->tv_usec = (d->bd_rtout % hz) * tick; 1250 break; 1251 } 1252 /* 1253 * Get packet stats. 1254 */ 1255 case BIOCGSTATS: { 1256 struct bpf_stat *bs = addr; 1257 1258 bs->bs_recv = d->bd_rcount; 1259 bs->bs_drop = d->bd_dcount; 1260 bs->bs_capt = d->bd_ccount; 1261 break; 1262 } 1263 1264 case BIOCGSTATS_30: { 1265 struct bpf_stat30 *bs = addr; 1266 1267 bs->bs_recv = d->bd_rcount; 1268 bs->bs_drop = d->bd_dcount; 1269 break; 1270 } 1271 1272 /* 1273 * Set immediate mode. 1274 */ 1275 case BIOCIMMEDIATE: 1276 d->bd_immediate = *(u_int *)addr; 1277 break; 1278 1279 case BIOCVERSION: { 1280 struct bpf_version *bv = addr; 1281 1282 bv->bv_major = BPF_MAJOR_VERSION; 1283 bv->bv_minor = BPF_MINOR_VERSION; 1284 break; 1285 } 1286 1287 case BIOCGHDRCMPLT: /* get "header already complete" flag */ 1288 *(u_int *)addr = d->bd_hdrcmplt; 1289 break; 1290 1291 case BIOCSHDRCMPLT: /* set "header already complete" flag */ 1292 d->bd_hdrcmplt = *(u_int *)addr ? 1 : 0; 1293 break; 1294 1295 /* 1296 * Get packet direction flag 1297 */ 1298 case BIOCGDIRECTION: 1299 *(u_int *)addr = d->bd_direction; 1300 break; 1301 1302 /* 1303 * Set packet direction flag 1304 */ 1305 case BIOCSDIRECTION: { 1306 u_int direction; 1307 1308 direction = *(u_int *)addr; 1309 switch (direction) { 1310 case BPF_D_IN: 1311 case BPF_D_INOUT: 1312 case BPF_D_OUT: 1313 d->bd_direction = direction; 1314 break; 1315 default: 1316 error = EINVAL; 1317 } 1318 } 1319 break; 1320 1321 /* 1322 * Set "feed packets from bpf back to input" mode 1323 */ 1324 case BIOCSFEEDBACK: 1325 d->bd_feedback = *(u_int *)addr; 1326 break; 1327 1328 /* 1329 * Get "feed packets from bpf back to input" mode 1330 */ 1331 case BIOCGFEEDBACK: 1332 *(u_int *)addr = d->bd_feedback; 1333 break; 1334 1335 case FIONBIO: /* Non-blocking I/O */ 1336 /* 1337 * No need to do anything special as we use IO_NDELAY in 1338 * bpfread() as an indication of whether or not to block 1339 * the read. 1340 */ 1341 break; 1342 1343 case FIOASYNC: /* Send signal on receive packets */ 1344 mutex_enter(d->bd_mtx); 1345 d->bd_async = *(int *)addr; 1346 mutex_exit(d->bd_mtx); 1347 break; 1348 1349 case TIOCSPGRP: /* Process or group to send signals to */ 1350 case FIOSETOWN: 1351 error = fsetown(&d->bd_pgid, cmd, addr); 1352 break; 1353 1354 case TIOCGPGRP: 1355 case FIOGETOWN: 1356 error = fgetown(d->bd_pgid, cmd, addr); 1357 break; 1358 } 1359 return (error); 1360 } 1361 1362 /* 1363 * Set d's packet filter program to fp. If this file already has a filter, 1364 * free it and replace it. Returns EINVAL for bogus requests. 1365 */ 1366 static int 1367 bpf_setf(struct bpf_d *d, struct bpf_program *fp, u_long cmd) 1368 { 1369 struct bpf_insn *fcode; 1370 bpfjit_func_t jcode; 1371 size_t flen, size = 0; 1372 struct bpf_filter *oldf, *newf, **storef; 1373 1374 jcode = NULL; 1375 flen = fp->bf_len; 1376 1377 if ((fp->bf_insns == NULL && flen) || flen > BPF_MAXINSNS) { 1378 return EINVAL; 1379 } 1380 1381 if (flen) { 1382 /* 1383 * Allocate the buffer, copy the byte-code from 1384 * userspace and validate it. 1385 */ 1386 size = flen * sizeof(*fp->bf_insns); 1387 fcode = kmem_alloc(size, KM_SLEEP); 1388 if (copyin(fp->bf_insns, fcode, size) != 0 || 1389 !bpf_validate(fcode, (int)flen)) { 1390 kmem_free(fcode, size); 1391 return EINVAL; 1392 } 1393 if (bpf_jit) 1394 jcode = bpf_jit_generate(NULL, fcode, flen); 1395 } else { 1396 fcode = NULL; 1397 } 1398 1399 newf = kmem_alloc(sizeof(*newf), KM_SLEEP); 1400 newf->bf_insn = fcode; 1401 newf->bf_size = size; 1402 newf->bf_jitcode = jcode; 1403 if (cmd == BIOCSETF) 1404 d->bd_jitcode = jcode; /* XXX just for kvm(3) users */ 1405 1406 /* Need to hold bpf_mtx for pserialize_perform */ 1407 mutex_enter(&bpf_mtx); 1408 mutex_enter(d->bd_mtx); 1409 if (cmd == BIOCSETWF) { 1410 oldf = d->bd_wfilter; 1411 storef = &d->bd_wfilter; 1412 } else { 1413 oldf = d->bd_rfilter; 1414 storef = &d->bd_rfilter; 1415 } 1416 atomic_store_release(storef, newf); 1417 reset_d(d); 1418 pserialize_perform(bpf_psz); 1419 mutex_exit(d->bd_mtx); 1420 mutex_exit(&bpf_mtx); 1421 1422 if (oldf != NULL) 1423 bpf_free_filter(oldf); 1424 1425 return 0; 1426 } 1427 1428 /* 1429 * Detach a file from its current interface (if attached at all) and attach 1430 * to the interface indicated by the name stored in ifr. 1431 * Return an errno or 0. 1432 */ 1433 static int 1434 bpf_setif(struct bpf_d *d, struct ifreq *ifr) 1435 { 1436 struct bpf_if *bp; 1437 char *cp; 1438 int unit_seen, i, error; 1439 1440 KASSERT(mutex_owned(&bpf_mtx)); 1441 /* 1442 * Make sure the provided name has a unit number, and default 1443 * it to '0' if not specified. 1444 * XXX This is ugly ... do this differently? 1445 */ 1446 unit_seen = 0; 1447 cp = ifr->ifr_name; 1448 cp[sizeof(ifr->ifr_name) - 1] = '\0'; /* sanity */ 1449 while (*cp++) 1450 if (*cp >= '0' && *cp <= '9') 1451 unit_seen = 1; 1452 if (!unit_seen) { 1453 /* Make sure to leave room for the '\0'. */ 1454 for (i = 0; i < (IFNAMSIZ - 1); ++i) { 1455 if ((ifr->ifr_name[i] >= 'a' && 1456 ifr->ifr_name[i] <= 'z') || 1457 (ifr->ifr_name[i] >= 'A' && 1458 ifr->ifr_name[i] <= 'Z')) 1459 continue; 1460 ifr->ifr_name[i] = '0'; 1461 } 1462 } 1463 1464 /* 1465 * Look through attached interfaces for the named one. 1466 */ 1467 BPF_IFLIST_WRITER_FOREACH(bp) { 1468 struct ifnet *ifp = bp->bif_ifp; 1469 1470 if (ifp == NULL || 1471 strcmp(ifp->if_xname, ifr->ifr_name) != 0) 1472 continue; 1473 /* skip additional entry */ 1474 if (bp->bif_driverp != &ifp->if_bpf) 1475 continue; 1476 /* 1477 * We found the requested interface. 1478 * Allocate the packet buffers if we need to. 1479 * If we're already attached to requested interface, 1480 * just flush the buffer. 1481 */ 1482 /* 1483 * bpf_allocbufs is called only here. bpf_mtx ensures that 1484 * no race condition happen on d->bd_sbuf. 1485 */ 1486 if (d->bd_sbuf == NULL) { 1487 error = bpf_allocbufs(d); 1488 if (error != 0) 1489 return (error); 1490 } 1491 mutex_enter(d->bd_mtx); 1492 if (bp != d->bd_bif) { 1493 if (d->bd_bif) { 1494 /* 1495 * Detach if attached to something else. 1496 */ 1497 bpf_detachd(d); 1498 BPFIF_DLIST_ENTRY_INIT(d); 1499 } 1500 1501 bpf_attachd(d, bp); 1502 } 1503 reset_d(d); 1504 mutex_exit(d->bd_mtx); 1505 return (0); 1506 } 1507 /* Not found. */ 1508 return (ENXIO); 1509 } 1510 1511 /* 1512 * Copy the interface name to the ifreq. 1513 */ 1514 static void 1515 bpf_ifname(struct ifnet *ifp, struct ifreq *ifr) 1516 { 1517 memcpy(ifr->ifr_name, ifp->if_xname, IFNAMSIZ); 1518 } 1519 1520 static int 1521 bpf_stat(struct file *fp, struct stat *st) 1522 { 1523 struct bpf_d *d = fp->f_bpf; 1524 1525 (void)memset(st, 0, sizeof(*st)); 1526 mutex_enter(d->bd_mtx); 1527 st->st_dev = makedev(cdevsw_lookup_major(&bpf_cdevsw), d->bd_pid); 1528 st->st_atimespec = d->bd_atime; 1529 st->st_mtimespec = d->bd_mtime; 1530 st->st_ctimespec = st->st_birthtimespec = d->bd_btime; 1531 st->st_uid = kauth_cred_geteuid(fp->f_cred); 1532 st->st_gid = kauth_cred_getegid(fp->f_cred); 1533 st->st_mode = S_IFCHR; 1534 mutex_exit(d->bd_mtx); 1535 return 0; 1536 } 1537 1538 /* 1539 * Support for poll() system call 1540 * 1541 * Return true iff the specific operation will not block indefinitely - with 1542 * the assumption that it is safe to positively acknowledge a request for the 1543 * ability to write to the BPF device. 1544 * Otherwise, return false but make a note that a selnotify() must be done. 1545 */ 1546 static int 1547 bpf_poll(struct file *fp, int events) 1548 { 1549 struct bpf_d *d = fp->f_bpf; 1550 int revents; 1551 1552 /* 1553 * Refresh the PID associated with this bpf file. 1554 */ 1555 mutex_enter(&bpf_mtx); 1556 d->bd_pid = curproc->p_pid; 1557 1558 revents = events & (POLLOUT | POLLWRNORM); 1559 if (events & (POLLIN | POLLRDNORM)) { 1560 /* 1561 * An imitation of the FIONREAD ioctl code. 1562 */ 1563 mutex_enter(d->bd_mtx); 1564 mutex_enter(d->bd_buf_mtx); 1565 if (d->bd_hlen != 0 || 1566 ((d->bd_immediate || d->bd_state == BPF_TIMED_OUT) && 1567 d->bd_slen != 0)) { 1568 revents |= events & (POLLIN | POLLRDNORM); 1569 } else { 1570 selrecord(curlwp, &d->bd_sel); 1571 /* Start the read timeout if necessary */ 1572 if (d->bd_rtout > 0 && d->bd_state == BPF_IDLE) { 1573 callout_reset(&d->bd_callout, d->bd_rtout, 1574 bpf_timed_out, d); 1575 d->bd_state = BPF_WAITING; 1576 } 1577 } 1578 mutex_exit(d->bd_buf_mtx); 1579 mutex_exit(d->bd_mtx); 1580 } 1581 1582 mutex_exit(&bpf_mtx); 1583 return (revents); 1584 } 1585 1586 static void 1587 filt_bpfrdetach(struct knote *kn) 1588 { 1589 struct bpf_d *d = kn->kn_hook; 1590 1591 mutex_enter(d->bd_buf_mtx); 1592 selremove_knote(&d->bd_sel, kn); 1593 mutex_exit(d->bd_buf_mtx); 1594 } 1595 1596 static int 1597 filt_bpfread(struct knote *kn, long hint) 1598 { 1599 struct bpf_d *d = kn->kn_hook; 1600 int rv; 1601 1602 /* 1603 * Refresh the PID associated with this bpf file. 1604 */ 1605 d->bd_pid = curproc->p_pid; 1606 1607 if (hint & NOTE_SUBMIT) 1608 KASSERT(mutex_owned(d->bd_buf_mtx)); 1609 else 1610 mutex_enter(d->bd_buf_mtx); 1611 kn->kn_data = d->bd_hlen; 1612 if (d->bd_immediate) 1613 kn->kn_data += d->bd_slen; 1614 rv = (kn->kn_data > 0); 1615 if (hint & NOTE_SUBMIT) 1616 KASSERT(mutex_owned(d->bd_buf_mtx)); 1617 else 1618 mutex_exit(d->bd_buf_mtx); 1619 return rv; 1620 } 1621 1622 static const struct filterops bpfread_filtops = { 1623 .f_flags = FILTEROP_ISFD | FILTEROP_MPSAFE, 1624 .f_attach = NULL, 1625 .f_detach = filt_bpfrdetach, 1626 .f_event = filt_bpfread, 1627 }; 1628 1629 static int 1630 bpf_kqfilter(struct file *fp, struct knote *kn) 1631 { 1632 struct bpf_d *d = fp->f_bpf; 1633 1634 switch (kn->kn_filter) { 1635 case EVFILT_READ: 1636 kn->kn_fop = &bpfread_filtops; 1637 break; 1638 1639 default: 1640 return (EINVAL); 1641 } 1642 1643 kn->kn_hook = d; 1644 1645 mutex_enter(d->bd_buf_mtx); 1646 selrecord_knote(&d->bd_sel, kn); 1647 mutex_exit(d->bd_buf_mtx); 1648 1649 return (0); 1650 } 1651 1652 /* 1653 * Copy data from an mbuf chain into a buffer. This code is derived 1654 * from m_copydata in sys/uipc_mbuf.c. 1655 */ 1656 static void * 1657 bpf_mcpy(void *dst_arg, const void *src_arg, size_t len) 1658 { 1659 const struct mbuf *m; 1660 u_int count; 1661 u_char *dst; 1662 1663 m = src_arg; 1664 dst = dst_arg; 1665 while (len > 0) { 1666 if (m == NULL) 1667 panic("bpf_mcpy"); 1668 count = uimin(m->m_len, len); 1669 memcpy(dst, mtod(m, const void *), count); 1670 m = m->m_next; 1671 dst += count; 1672 len -= count; 1673 } 1674 return dst_arg; 1675 } 1676 1677 static inline u_int 1678 bpf_xfilter(struct bpf_filter **filter, void *pkt, u_int pktlen, u_int buflen) 1679 { 1680 struct bpf_filter *filt; 1681 uint32_t mem[BPF_MEMWORDS]; 1682 bpf_args_t args = { 1683 .pkt = (const uint8_t *)pkt, 1684 .wirelen = pktlen, 1685 .buflen = buflen, 1686 .mem = mem, 1687 .arg = NULL 1688 }; 1689 u_int slen; 1690 1691 filt = atomic_load_consume(filter); 1692 if (filt == NULL) /* No filter means accept all. */ 1693 return (u_int)-1; 1694 1695 if (filt->bf_jitcode != NULL) 1696 slen = filt->bf_jitcode(NULL, &args); 1697 else 1698 slen = bpf_filter_ext(NULL, filt->bf_insn, &args); 1699 return slen; 1700 } 1701 1702 /* 1703 * Dispatch a packet to all the listeners on interface bp. 1704 * 1705 * pkt pointer to the packet, either a data buffer or an mbuf chain 1706 * buflen buffer length, if pkt is a data buffer 1707 * cpfn a function that can copy pkt into the listener's buffer 1708 * pktlen length of the packet 1709 * direction BPF_D_IN or BPF_D_OUT 1710 */ 1711 static inline void 1712 bpf_deliver(struct bpf_if *bp, void *(*cpfn)(void *, const void *, size_t), 1713 void *pkt, u_int pktlen, u_int buflen, const u_int direction) 1714 { 1715 bool gottime = false; 1716 struct timespec ts; 1717 struct bpf_d *d; 1718 int s; 1719 u_int slen; 1720 1721 KASSERT(!cpu_intr_p()); 1722 1723 /* 1724 * Note that the IPL does not have to be raised at this point. 1725 * The only problem that could arise here is that if two different 1726 * interfaces shared any data. This is not the case. 1727 */ 1728 s = pserialize_read_enter(); 1729 BPFIF_DLIST_READER_FOREACH(d, bp) { 1730 if (direction == BPF_D_IN) { 1731 if (d->bd_direction == BPF_D_OUT) 1732 continue; 1733 } else { /* BPF_D_OUT */ 1734 if (d->bd_direction == BPF_D_IN) 1735 continue; 1736 } 1737 1738 atomic_inc_ulong(&d->bd_rcount); 1739 BPF_STATINC(recv); 1740 1741 slen = bpf_xfilter(&d->bd_rfilter, pkt, pktlen, buflen); 1742 if (slen == 0) 1743 continue; 1744 1745 if (!gottime) { 1746 gottime = true; 1747 nanotime(&ts); 1748 } 1749 /* Assume catchpacket doesn't sleep */ 1750 catchpacket(d, pkt, pktlen, slen, cpfn, &ts); 1751 } 1752 pserialize_read_exit(s); 1753 } 1754 1755 /* 1756 * Incoming linkage from device drivers, when the head of the packet is in 1757 * a buffer, and the tail is in an mbuf chain. 1758 */ 1759 static void 1760 _bpf_mtap2(struct bpf_if *bp, void *data, u_int dlen, struct mbuf *m, 1761 u_int direction) 1762 { 1763 u_int pktlen; 1764 struct mbuf mb; 1765 1766 /* Skip outgoing duplicate packets. */ 1767 if ((m->m_flags & M_PROMISC) != 0 && m->m_pkthdr.rcvif_index == 0) { 1768 m->m_flags &= ~M_PROMISC; 1769 return; 1770 } 1771 1772 pktlen = m_length(m) + dlen; 1773 1774 /* 1775 * Craft on-stack mbuf suitable for passing to bpf_filter. 1776 * Note that we cut corners here; we only set up what's 1777 * absolutely needed--this mbuf should never go anywhere else. 1778 */ 1779 (void)memset(&mb, 0, sizeof(mb)); 1780 mb.m_type = MT_DATA; 1781 mb.m_next = m; 1782 mb.m_data = data; 1783 mb.m_len = dlen; 1784 1785 bpf_deliver(bp, bpf_mcpy, &mb, pktlen, 0, direction); 1786 } 1787 1788 /* 1789 * Incoming linkage from device drivers, when packet is in an mbuf chain. 1790 */ 1791 static void 1792 _bpf_mtap(struct bpf_if *bp, struct mbuf *m, u_int direction) 1793 { 1794 void *(*cpfn)(void *, const void *, size_t); 1795 u_int pktlen, buflen; 1796 void *marg; 1797 1798 /* Skip outgoing duplicate packets. */ 1799 if ((m->m_flags & M_PROMISC) != 0 && m->m_pkthdr.rcvif_index == 0) { 1800 m->m_flags &= ~M_PROMISC; 1801 return; 1802 } 1803 1804 pktlen = m_length(m); 1805 1806 /* Skip zero-sized packets. */ 1807 if (__predict_false(pktlen == 0)) { 1808 return; 1809 } 1810 1811 if (pktlen == m->m_len) { 1812 cpfn = (void *)memcpy; 1813 marg = mtod(m, void *); 1814 buflen = pktlen; 1815 KASSERT(buflen != 0); 1816 } else { 1817 cpfn = bpf_mcpy; 1818 marg = m; 1819 buflen = 0; 1820 } 1821 1822 bpf_deliver(bp, cpfn, marg, pktlen, buflen, direction); 1823 } 1824 1825 /* 1826 * We need to prepend the address family as 1827 * a four byte field. Cons up a dummy header 1828 * to pacify bpf. This is safe because bpf 1829 * will only read from the mbuf (i.e., it won't 1830 * try to free it or keep a pointer a to it). 1831 */ 1832 static void 1833 _bpf_mtap_af(struct bpf_if *bp, uint32_t af, struct mbuf *m, u_int direction) 1834 { 1835 struct mbuf m0; 1836 1837 m0.m_type = MT_DATA; 1838 m0.m_flags = 0; 1839 m0.m_next = m; 1840 m0.m_nextpkt = NULL; 1841 m0.m_owner = NULL; 1842 m0.m_len = 4; 1843 m0.m_data = (char *)⁡ 1844 1845 _bpf_mtap(bp, &m0, direction); 1846 } 1847 1848 /* 1849 * Put the SLIP pseudo-"link header" in place. 1850 * Note this M_PREPEND() should never fail, 1851 * since we know we always have enough space 1852 * in the input buffer. 1853 */ 1854 static void 1855 _bpf_mtap_sl_in(struct bpf_if *bp, u_char *chdr, struct mbuf **m) 1856 { 1857 u_char *hp; 1858 1859 M_PREPEND(*m, SLIP_HDRLEN, M_DONTWAIT); 1860 if (*m == NULL) 1861 return; 1862 1863 hp = mtod(*m, u_char *); 1864 hp[SLX_DIR] = SLIPDIR_IN; 1865 (void)memcpy(&hp[SLX_CHDR], chdr, CHDR_LEN); 1866 1867 _bpf_mtap(bp, *m, BPF_D_IN); 1868 1869 m_adj(*m, SLIP_HDRLEN); 1870 } 1871 1872 /* 1873 * Put the SLIP pseudo-"link header" in 1874 * place. The compressed header is now 1875 * at the beginning of the mbuf. 1876 */ 1877 static void 1878 _bpf_mtap_sl_out(struct bpf_if *bp, u_char *chdr, struct mbuf *m) 1879 { 1880 struct mbuf m0; 1881 u_char *hp; 1882 1883 m0.m_type = MT_DATA; 1884 m0.m_flags = 0; 1885 m0.m_next = m; 1886 m0.m_nextpkt = NULL; 1887 m0.m_owner = NULL; 1888 m0.m_data = m0.m_dat; 1889 m0.m_len = SLIP_HDRLEN; 1890 1891 hp = mtod(&m0, u_char *); 1892 1893 hp[SLX_DIR] = SLIPDIR_OUT; 1894 (void)memcpy(&hp[SLX_CHDR], chdr, CHDR_LEN); 1895 1896 _bpf_mtap(bp, &m0, BPF_D_OUT); 1897 m_freem(m); 1898 } 1899 1900 static struct mbuf * 1901 bpf_mbuf_enqueue(struct bpf_if *bp, struct mbuf *m) 1902 { 1903 struct mbuf *dup; 1904 1905 dup = m_dup(m, 0, M_COPYALL, M_NOWAIT); 1906 if (dup == NULL) 1907 return NULL; 1908 1909 if (bp->bif_mbuf_tail != NULL) { 1910 bp->bif_mbuf_tail->m_nextpkt = dup; 1911 } else { 1912 bp->bif_mbuf_head = dup; 1913 } 1914 bp->bif_mbuf_tail = dup; 1915 #ifdef BPF_MTAP_SOFTINT_DEBUG 1916 log(LOG_DEBUG, "%s: enqueued mbuf=%p to %s\n", 1917 __func__, dup, bp->bif_ifp->if_xname); 1918 #endif 1919 1920 return dup; 1921 } 1922 1923 static struct mbuf * 1924 bpf_mbuf_dequeue(struct bpf_if *bp) 1925 { 1926 struct mbuf *m; 1927 int s; 1928 1929 /* XXX NOMPSAFE: assumed running on one CPU */ 1930 s = splnet(); 1931 m = bp->bif_mbuf_head; 1932 if (m != NULL) { 1933 bp->bif_mbuf_head = m->m_nextpkt; 1934 m->m_nextpkt = NULL; 1935 1936 if (bp->bif_mbuf_head == NULL) 1937 bp->bif_mbuf_tail = NULL; 1938 #ifdef BPF_MTAP_SOFTINT_DEBUG 1939 log(LOG_DEBUG, "%s: dequeued mbuf=%p from %s\n", 1940 __func__, m, bp->bif_ifp->if_xname); 1941 #endif 1942 } 1943 splx(s); 1944 1945 return m; 1946 } 1947 1948 static void 1949 bpf_mtap_si(void *arg) 1950 { 1951 struct bpf_if *bp = arg; 1952 struct mbuf *m; 1953 1954 while ((m = bpf_mbuf_dequeue(bp)) != NULL) { 1955 #ifdef BPF_MTAP_SOFTINT_DEBUG 1956 log(LOG_DEBUG, "%s: tapping mbuf=%p on %s\n", 1957 __func__, m, bp->bif_ifp->if_xname); 1958 #endif 1959 bpf_ops->bpf_mtap(bp, m, BPF_D_IN); 1960 m_freem(m); 1961 } 1962 } 1963 1964 static void 1965 _bpf_mtap_softint(struct ifnet *ifp, struct mbuf *m) 1966 { 1967 struct bpf_if *bp = ifp->if_bpf; 1968 struct mbuf *dup; 1969 1970 KASSERT(cpu_intr_p()); 1971 1972 /* To avoid extra invocations of the softint */ 1973 if (BPFIF_DLIST_READER_EMPTY(bp)) 1974 return; 1975 KASSERT(bp->bif_si != NULL); 1976 1977 dup = bpf_mbuf_enqueue(bp, m); 1978 if (dup != NULL) 1979 softint_schedule(bp->bif_si); 1980 } 1981 1982 static int 1983 bpf_hdrlen(struct bpf_d *d) 1984 { 1985 int hdrlen = d->bd_bif->bif_hdrlen; 1986 /* 1987 * Compute the length of the bpf header. This is not necessarily 1988 * equal to SIZEOF_BPF_HDR because we want to insert spacing such 1989 * that the network layer header begins on a longword boundary (for 1990 * performance reasons and to alleviate alignment restrictions). 1991 */ 1992 #ifdef _LP64 1993 if (d->bd_compat32) 1994 return (BPF_WORDALIGN32(hdrlen + SIZEOF_BPF_HDR32) - hdrlen); 1995 else 1996 #endif 1997 return (BPF_WORDALIGN(hdrlen + SIZEOF_BPF_HDR) - hdrlen); 1998 } 1999 2000 /* 2001 * Move the packet data from interface memory (pkt) into the 2002 * store buffer. Call the wakeup functions if it's time to wake up 2003 * a listener (buffer full), "cpfn" is the routine called to do the 2004 * actual data transfer. memcpy is passed in to copy contiguous chunks, 2005 * while bpf_mcpy is passed in to copy mbuf chains. In the latter case, 2006 * pkt is really an mbuf. 2007 */ 2008 static void 2009 catchpacket(struct bpf_d *d, u_char *pkt, u_int pktlen, u_int snaplen, 2010 void *(*cpfn)(void *, const void *, size_t), struct timespec *ts) 2011 { 2012 char *h; 2013 int totlen, curlen, caplen; 2014 int hdrlen = bpf_hdrlen(d); 2015 int do_wakeup = 0; 2016 2017 atomic_inc_ulong(&d->bd_ccount); 2018 BPF_STATINC(capt); 2019 /* 2020 * Figure out how many bytes to move. If the packet is 2021 * greater or equal to the snapshot length, transfer that 2022 * much. Otherwise, transfer the whole packet (unless 2023 * we hit the buffer size limit). 2024 */ 2025 totlen = hdrlen + uimin(snaplen, pktlen); 2026 if (totlen > d->bd_bufsize) 2027 totlen = d->bd_bufsize; 2028 /* 2029 * If we adjusted totlen to fit the bufsize, it could be that 2030 * totlen is smaller than hdrlen because of the link layer header. 2031 */ 2032 caplen = totlen - hdrlen; 2033 if (caplen < 0) 2034 caplen = 0; 2035 2036 mutex_enter(d->bd_buf_mtx); 2037 /* 2038 * Round up the end of the previous packet to the next longword. 2039 */ 2040 #ifdef _LP64 2041 if (d->bd_compat32) 2042 curlen = BPF_WORDALIGN32(d->bd_slen); 2043 else 2044 #endif 2045 curlen = BPF_WORDALIGN(d->bd_slen); 2046 if (curlen + totlen > d->bd_bufsize) { 2047 /* 2048 * This packet will overflow the storage buffer. 2049 * Rotate the buffers if we can, then wakeup any 2050 * pending reads. 2051 */ 2052 if (d->bd_fbuf == NULL) { 2053 mutex_exit(d->bd_buf_mtx); 2054 /* 2055 * We haven't completed the previous read yet, 2056 * so drop the packet. 2057 */ 2058 atomic_inc_ulong(&d->bd_dcount); 2059 BPF_STATINC(drop); 2060 return; 2061 } 2062 ROTATE_BUFFERS(d); 2063 do_wakeup = 1; 2064 curlen = 0; 2065 } else if (d->bd_immediate || d->bd_state == BPF_TIMED_OUT) { 2066 /* 2067 * Immediate mode is set, or the read timeout has 2068 * already expired during a select call. A packet 2069 * arrived, so the reader should be woken up. 2070 */ 2071 do_wakeup = 1; 2072 } 2073 2074 /* 2075 * Append the bpf header. 2076 */ 2077 h = (char *)d->bd_sbuf + curlen; 2078 #ifdef _LP64 2079 if (d->bd_compat32) { 2080 struct bpf_hdr32 *hp32; 2081 2082 hp32 = (struct bpf_hdr32 *)h; 2083 hp32->bh_tstamp.tv_sec = ts->tv_sec; 2084 hp32->bh_tstamp.tv_usec = ts->tv_nsec / 1000; 2085 hp32->bh_datalen = pktlen; 2086 hp32->bh_hdrlen = hdrlen; 2087 hp32->bh_caplen = caplen; 2088 } else 2089 #endif 2090 { 2091 struct bpf_hdr *hp; 2092 2093 hp = (struct bpf_hdr *)h; 2094 hp->bh_tstamp.tv_sec = ts->tv_sec; 2095 hp->bh_tstamp.tv_usec = ts->tv_nsec / 1000; 2096 hp->bh_datalen = pktlen; 2097 hp->bh_hdrlen = hdrlen; 2098 hp->bh_caplen = caplen; 2099 } 2100 2101 /* 2102 * Copy the packet data into the store buffer and update its length. 2103 */ 2104 (*cpfn)(h + hdrlen, pkt, caplen); 2105 d->bd_slen = curlen + totlen; 2106 2107 /* 2108 * Call bpf_wakeup after bd_slen has been updated so that kevent(2) 2109 * will cause filt_bpfread() to be called with it adjusted. 2110 */ 2111 if (do_wakeup) 2112 bpf_wakeup(d); 2113 2114 mutex_exit(d->bd_buf_mtx); 2115 } 2116 2117 /* 2118 * Initialize all nonzero fields of a descriptor. 2119 */ 2120 static int 2121 bpf_allocbufs(struct bpf_d *d) 2122 { 2123 2124 d->bd_fbuf = kmem_zalloc(d->bd_bufsize, KM_NOSLEEP); 2125 if (!d->bd_fbuf) 2126 return (ENOBUFS); 2127 d->bd_sbuf = kmem_zalloc(d->bd_bufsize, KM_NOSLEEP); 2128 if (!d->bd_sbuf) { 2129 kmem_free(d->bd_fbuf, d->bd_bufsize); 2130 return (ENOBUFS); 2131 } 2132 d->bd_slen = 0; 2133 d->bd_hlen = 0; 2134 return (0); 2135 } 2136 2137 static void 2138 bpf_free_filter(struct bpf_filter *filter) 2139 { 2140 2141 KASSERT(filter != NULL); 2142 2143 if (filter->bf_insn != NULL) 2144 kmem_free(filter->bf_insn, filter->bf_size); 2145 if (filter->bf_jitcode != NULL) 2146 bpf_jit_freecode(filter->bf_jitcode); 2147 kmem_free(filter, sizeof(*filter)); 2148 } 2149 2150 /* 2151 * Free buffers currently in use by a descriptor. 2152 * Called on close. 2153 */ 2154 static void 2155 bpf_freed(struct bpf_d *d) 2156 { 2157 /* 2158 * We don't need to lock out interrupts since this descriptor has 2159 * been detached from its interface and it yet hasn't been marked 2160 * free. 2161 */ 2162 if (d->bd_sbuf != NULL) { 2163 kmem_free(d->bd_sbuf, d->bd_bufsize); 2164 if (d->bd_hbuf != NULL) 2165 kmem_free(d->bd_hbuf, d->bd_bufsize); 2166 if (d->bd_fbuf != NULL) 2167 kmem_free(d->bd_fbuf, d->bd_bufsize); 2168 } 2169 if (d->bd_rfilter != NULL) { 2170 bpf_free_filter(d->bd_rfilter); 2171 d->bd_rfilter = NULL; 2172 } 2173 if (d->bd_wfilter != NULL) { 2174 bpf_free_filter(d->bd_wfilter); 2175 d->bd_wfilter = NULL; 2176 } 2177 d->bd_jitcode = NULL; 2178 } 2179 2180 /* 2181 * Attach an interface to bpf. dlt is the link layer type; 2182 * hdrlen is the fixed size of the link header for the specified dlt 2183 * (variable length headers not yet supported). 2184 */ 2185 static void 2186 _bpfattach(struct ifnet *ifp, u_int dlt, u_int hdrlen, struct bpf_if **driverp) 2187 { 2188 struct bpf_if *bp; 2189 2190 bp = kmem_alloc(sizeof(*bp), KM_SLEEP); 2191 2192 mutex_enter(&bpf_mtx); 2193 bp->bif_driverp = driverp; 2194 bp->bif_ifp = ifp; 2195 bp->bif_dlt = dlt; 2196 bp->bif_si = NULL; 2197 BPF_IFLIST_ENTRY_INIT(bp); 2198 PSLIST_INIT(&bp->bif_dlist_head); 2199 psref_target_init(&bp->bif_psref, bpf_psref_class); 2200 SLIST_INIT(&bp->bif_trackers); 2201 2202 BPF_IFLIST_WRITER_INSERT_HEAD(bp); 2203 2204 *bp->bif_driverp = NULL; 2205 2206 bp->bif_hdrlen = hdrlen; 2207 mutex_exit(&bpf_mtx); 2208 #if 0 2209 printf("bpf: %s attached with dlt %x\n", ifp->if_xname, dlt); 2210 #endif 2211 } 2212 2213 static void 2214 _bpf_mtap_softint_init(struct ifnet *ifp) 2215 { 2216 struct bpf_if *bp; 2217 2218 mutex_enter(&bpf_mtx); 2219 BPF_IFLIST_WRITER_FOREACH(bp) { 2220 if (bp->bif_ifp != ifp) 2221 continue; 2222 2223 bp->bif_mbuf_head = NULL; 2224 bp->bif_mbuf_tail = NULL; 2225 bp->bif_si = softint_establish(SOFTINT_NET, bpf_mtap_si, bp); 2226 if (bp->bif_si == NULL) 2227 panic("%s: softint_establish() failed", __func__); 2228 break; 2229 } 2230 mutex_exit(&bpf_mtx); 2231 2232 if (bp == NULL) 2233 panic("%s: no bpf_if found for %s", __func__, ifp->if_xname); 2234 } 2235 2236 /* 2237 * Remove an interface from bpf. 2238 */ 2239 static void 2240 _bpfdetach(struct ifnet *ifp) 2241 { 2242 struct bpf_if *bp; 2243 struct bpf_d *d; 2244 int s; 2245 2246 mutex_enter(&bpf_mtx); 2247 /* Nuke the vnodes for any open instances */ 2248 again_d: 2249 BPF_DLIST_WRITER_FOREACH(d) { 2250 mutex_enter(d->bd_mtx); 2251 if (d->bd_bif != NULL && d->bd_bif->bif_ifp == ifp) { 2252 /* 2253 * Detach the descriptor from an interface now. 2254 * It will be free'ed later by close routine. 2255 */ 2256 bpf_detachd(d); 2257 mutex_exit(d->bd_mtx); 2258 goto again_d; 2259 } 2260 mutex_exit(d->bd_mtx); 2261 } 2262 2263 again: 2264 BPF_IFLIST_WRITER_FOREACH(bp) { 2265 if (bp->bif_ifp == ifp) { 2266 BPF_IFLIST_WRITER_REMOVE(bp); 2267 2268 pserialize_perform(bpf_psz); 2269 psref_target_destroy(&bp->bif_psref, bpf_psref_class); 2270 2271 while (!SLIST_EMPTY(&bp->bif_trackers)) { 2272 struct bpf_event_tracker *t = 2273 SLIST_FIRST(&bp->bif_trackers); 2274 SLIST_REMOVE_HEAD(&bp->bif_trackers, 2275 bet_entries); 2276 kmem_free(t, sizeof(*t)); 2277 } 2278 2279 BPF_IFLIST_ENTRY_DESTROY(bp); 2280 if (bp->bif_si != NULL) { 2281 /* XXX NOMPSAFE: assumed running on one CPU */ 2282 s = splnet(); 2283 while (bp->bif_mbuf_head != NULL) { 2284 struct mbuf *m = bp->bif_mbuf_head; 2285 bp->bif_mbuf_head = m->m_nextpkt; 2286 m_freem(m); 2287 } 2288 splx(s); 2289 softint_disestablish(bp->bif_si); 2290 } 2291 kmem_free(bp, sizeof(*bp)); 2292 goto again; 2293 } 2294 } 2295 mutex_exit(&bpf_mtx); 2296 } 2297 2298 /* 2299 * Change the data link type of a interface. 2300 */ 2301 static void 2302 _bpf_change_type(struct ifnet *ifp, u_int dlt, u_int hdrlen) 2303 { 2304 struct bpf_if *bp; 2305 2306 mutex_enter(&bpf_mtx); 2307 BPF_IFLIST_WRITER_FOREACH(bp) { 2308 if (bp->bif_driverp == &ifp->if_bpf) 2309 break; 2310 } 2311 if (bp == NULL) 2312 panic("bpf_change_type"); 2313 2314 bp->bif_dlt = dlt; 2315 2316 bp->bif_hdrlen = hdrlen; 2317 mutex_exit(&bpf_mtx); 2318 } 2319 2320 /* 2321 * Get a list of available data link type of the interface. 2322 */ 2323 static int 2324 bpf_getdltlist(struct bpf_d *d, struct bpf_dltlist *bfl) 2325 { 2326 int n, error; 2327 struct ifnet *ifp; 2328 struct bpf_if *bp; 2329 int s, bound; 2330 2331 KASSERT(mutex_owned(d->bd_mtx)); 2332 2333 ifp = d->bd_bif->bif_ifp; 2334 n = 0; 2335 error = 0; 2336 2337 bound = curlwp_bind(); 2338 s = pserialize_read_enter(); 2339 BPF_IFLIST_READER_FOREACH(bp) { 2340 if (bp->bif_ifp != ifp) 2341 continue; 2342 if (bfl->bfl_list != NULL) { 2343 struct psref psref; 2344 2345 if (n >= bfl->bfl_len) { 2346 pserialize_read_exit(s); 2347 return ENOMEM; 2348 } 2349 2350 bpf_if_acquire(bp, &psref); 2351 pserialize_read_exit(s); 2352 2353 error = copyout(&bp->bif_dlt, 2354 bfl->bfl_list + n, sizeof(u_int)); 2355 2356 s = pserialize_read_enter(); 2357 bpf_if_release(bp, &psref); 2358 } 2359 n++; 2360 } 2361 pserialize_read_exit(s); 2362 curlwp_bindx(bound); 2363 2364 bfl->bfl_len = n; 2365 return error; 2366 } 2367 2368 /* 2369 * Set the data link type of a BPF instance. 2370 */ 2371 static int 2372 bpf_setdlt(struct bpf_d *d, u_int dlt) 2373 { 2374 int error, opromisc; 2375 struct ifnet *ifp; 2376 struct bpf_if *bp; 2377 2378 KASSERT(mutex_owned(&bpf_mtx)); 2379 KASSERT(mutex_owned(d->bd_mtx)); 2380 2381 if (d->bd_bif->bif_dlt == dlt) 2382 return 0; 2383 ifp = d->bd_bif->bif_ifp; 2384 BPF_IFLIST_WRITER_FOREACH(bp) { 2385 if (bp->bif_ifp == ifp && bp->bif_dlt == dlt) 2386 break; 2387 } 2388 if (bp == NULL) 2389 return EINVAL; 2390 opromisc = d->bd_promisc; 2391 bpf_detachd(d); 2392 BPFIF_DLIST_ENTRY_INIT(d); 2393 bpf_attachd(d, bp); 2394 reset_d(d); 2395 if (opromisc) { 2396 KERNEL_LOCK_UNLESS_NET_MPSAFE(); 2397 error = ifpromisc(bp->bif_ifp, 1); 2398 KERNEL_UNLOCK_UNLESS_NET_MPSAFE(); 2399 if (error) 2400 printf("%s: bpf_setdlt: ifpromisc failed (%d)\n", 2401 bp->bif_ifp->if_xname, error); 2402 else 2403 d->bd_promisc = 1; 2404 } 2405 return 0; 2406 } 2407 2408 static int 2409 sysctl_net_bpf_maxbufsize(SYSCTLFN_ARGS) 2410 { 2411 int newsize, error; 2412 struct sysctlnode node; 2413 2414 node = *rnode; 2415 node.sysctl_data = &newsize; 2416 newsize = bpf_maxbufsize; 2417 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2418 if (error || newp == NULL) 2419 return (error); 2420 2421 if (newsize < BPF_MINBUFSIZE || newsize > BPF_MAXBUFSIZE) 2422 return (EINVAL); 2423 2424 bpf_maxbufsize = newsize; 2425 2426 return (0); 2427 } 2428 2429 #if defined(MODULAR) || defined(BPFJIT) 2430 static int 2431 sysctl_net_bpf_jit(SYSCTLFN_ARGS) 2432 { 2433 bool newval; 2434 int error; 2435 struct sysctlnode node; 2436 2437 node = *rnode; 2438 node.sysctl_data = &newval; 2439 newval = bpf_jit; 2440 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2441 if (error != 0 || newp == NULL) 2442 return error; 2443 2444 bpf_jit = newval; 2445 if (newval && bpfjit_module_ops.bj_generate_code == NULL) { 2446 printf("JIT compilation is postponed " 2447 "until after bpfjit module is loaded\n"); 2448 } 2449 2450 return 0; 2451 } 2452 #endif 2453 2454 static int 2455 sysctl_net_bpf_peers(SYSCTLFN_ARGS) 2456 { 2457 int error, elem_count; 2458 struct bpf_d *dp; 2459 struct bpf_d_ext dpe; 2460 size_t len, needed, elem_size, out_size; 2461 char *sp; 2462 2463 if (namelen == 1 && name[0] == CTL_QUERY) 2464 return (sysctl_query(SYSCTLFN_CALL(rnode))); 2465 2466 if (namelen != 2) 2467 return (EINVAL); 2468 2469 /* BPF peers is privileged information. */ 2470 error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_INTERFACE, 2471 KAUTH_REQ_NETWORK_INTERFACE_GETPRIV, NULL, NULL, NULL); 2472 if (error) 2473 return (EPERM); 2474 2475 len = (oldp != NULL) ? *oldlenp : 0; 2476 sp = oldp; 2477 elem_size = name[0]; 2478 elem_count = name[1]; 2479 out_size = MIN(sizeof(dpe), elem_size); 2480 needed = 0; 2481 2482 if (elem_size < 1 || elem_count < 0) 2483 return (EINVAL); 2484 2485 mutex_enter(&bpf_mtx); 2486 BPF_DLIST_WRITER_FOREACH(dp) { 2487 if (len >= elem_size && elem_count > 0) { 2488 #define BPF_EXT(field) dpe.bde_ ## field = dp->bd_ ## field 2489 BPF_EXT(bufsize); 2490 BPF_EXT(promisc); 2491 BPF_EXT(state); 2492 BPF_EXT(immediate); 2493 BPF_EXT(hdrcmplt); 2494 BPF_EXT(direction); 2495 BPF_EXT(pid); 2496 BPF_EXT(rcount); 2497 BPF_EXT(dcount); 2498 BPF_EXT(ccount); 2499 #undef BPF_EXT 2500 mutex_enter(dp->bd_mtx); 2501 if (dp->bd_bif) 2502 (void)strlcpy(dpe.bde_ifname, 2503 dp->bd_bif->bif_ifp->if_xname, 2504 IFNAMSIZ - 1); 2505 else 2506 dpe.bde_ifname[0] = '\0'; 2507 dpe.bde_locked = dp->bd_locked; 2508 mutex_exit(dp->bd_mtx); 2509 2510 error = copyout(&dpe, sp, out_size); 2511 if (error) 2512 break; 2513 sp += elem_size; 2514 len -= elem_size; 2515 } 2516 needed += elem_size; 2517 if (elem_count > 0 && elem_count != INT_MAX) 2518 elem_count--; 2519 } 2520 mutex_exit(&bpf_mtx); 2521 2522 *oldlenp = needed; 2523 2524 return (error); 2525 } 2526 2527 static void 2528 bpf_stats(void *p, void *arg, struct cpu_info *ci __unused) 2529 { 2530 struct bpf_stat *const stats = p; 2531 struct bpf_stat *sum = arg; 2532 2533 int s = splnet(); 2534 2535 sum->bs_recv += stats->bs_recv; 2536 sum->bs_drop += stats->bs_drop; 2537 sum->bs_capt += stats->bs_capt; 2538 2539 splx(s); 2540 } 2541 2542 static int 2543 bpf_sysctl_gstats_handler(SYSCTLFN_ARGS) 2544 { 2545 struct sysctlnode node; 2546 int error; 2547 struct bpf_stat sum; 2548 2549 memset(&sum, 0, sizeof(sum)); 2550 node = *rnode; 2551 2552 percpu_foreach_xcall(bpf_gstats_percpu, XC_HIGHPRI_IPL(IPL_SOFTNET), 2553 bpf_stats, &sum); 2554 2555 node.sysctl_data = ∑ 2556 node.sysctl_size = sizeof(sum); 2557 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 2558 if (error != 0 || newp == NULL) 2559 return error; 2560 2561 return 0; 2562 } 2563 2564 SYSCTL_SETUP(sysctl_net_bpf_setup, "bpf sysctls") 2565 { 2566 const struct sysctlnode *node; 2567 2568 node = NULL; 2569 sysctl_createv(clog, 0, NULL, &node, 2570 CTLFLAG_PERMANENT, 2571 CTLTYPE_NODE, "bpf", 2572 SYSCTL_DESCR("BPF options"), 2573 NULL, 0, NULL, 0, 2574 CTL_NET, CTL_CREATE, CTL_EOL); 2575 if (node != NULL) { 2576 #if defined(MODULAR) || defined(BPFJIT) 2577 sysctl_createv(clog, 0, NULL, NULL, 2578 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2579 CTLTYPE_BOOL, "jit", 2580 SYSCTL_DESCR("Toggle Just-In-Time compilation"), 2581 sysctl_net_bpf_jit, 0, &bpf_jit, 0, 2582 CTL_NET, node->sysctl_num, CTL_CREATE, CTL_EOL); 2583 #endif 2584 sysctl_createv(clog, 0, NULL, NULL, 2585 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2586 CTLTYPE_INT, "maxbufsize", 2587 SYSCTL_DESCR("Maximum size for data capture buffer"), 2588 sysctl_net_bpf_maxbufsize, 0, &bpf_maxbufsize, 0, 2589 CTL_NET, node->sysctl_num, CTL_CREATE, CTL_EOL); 2590 sysctl_createv(clog, 0, NULL, NULL, 2591 CTLFLAG_PERMANENT, 2592 CTLTYPE_STRUCT, "stats", 2593 SYSCTL_DESCR("BPF stats"), 2594 bpf_sysctl_gstats_handler, 0, NULL, 0, 2595 CTL_NET, node->sysctl_num, CTL_CREATE, CTL_EOL); 2596 sysctl_createv(clog, 0, NULL, NULL, 2597 CTLFLAG_PERMANENT, 2598 CTLTYPE_STRUCT, "peers", 2599 SYSCTL_DESCR("BPF peers"), 2600 sysctl_net_bpf_peers, 0, NULL, 0, 2601 CTL_NET, node->sysctl_num, CTL_CREATE, CTL_EOL); 2602 } 2603 2604 } 2605 2606 static int 2607 _bpf_register_track_event(struct bpf_if **driverp, 2608 void (*_fun)(struct bpf_if *, struct ifnet *, int, int)) 2609 { 2610 struct bpf_if *bp; 2611 struct bpf_event_tracker *t; 2612 int ret = ENOENT; 2613 2614 t = kmem_zalloc(sizeof(*t), KM_SLEEP); 2615 if (!t) 2616 return ENOMEM; 2617 t->bet_notify = _fun; 2618 2619 mutex_enter(&bpf_mtx); 2620 BPF_IFLIST_WRITER_FOREACH(bp) { 2621 if (bp->bif_driverp != driverp) 2622 continue; 2623 SLIST_INSERT_HEAD(&bp->bif_trackers, t, bet_entries); 2624 ret = 0; 2625 break; 2626 } 2627 mutex_exit(&bpf_mtx); 2628 2629 return ret; 2630 } 2631 2632 static int 2633 _bpf_deregister_track_event(struct bpf_if **driverp, 2634 void (*_fun)(struct bpf_if *, struct ifnet *, int, int)) 2635 { 2636 struct bpf_if *bp; 2637 struct bpf_event_tracker *t = NULL; 2638 int ret = ENOENT; 2639 2640 mutex_enter(&bpf_mtx); 2641 BPF_IFLIST_WRITER_FOREACH(bp) { 2642 if (bp->bif_driverp != driverp) 2643 continue; 2644 SLIST_FOREACH(t, &bp->bif_trackers, bet_entries) { 2645 if (t->bet_notify == _fun) { 2646 ret = 0; 2647 break; 2648 } 2649 } 2650 if (ret == 0) 2651 break; 2652 } 2653 if (ret == 0 && t && t->bet_notify == _fun) { 2654 SLIST_REMOVE(&bp->bif_trackers, t, bpf_event_tracker, 2655 bet_entries); 2656 } 2657 mutex_exit(&bpf_mtx); 2658 if (ret == 0) 2659 kmem_free(t, sizeof(*t)); 2660 return ret; 2661 } 2662 2663 struct bpf_ops bpf_ops_kernel = { 2664 .bpf_attach = _bpfattach, 2665 .bpf_detach = _bpfdetach, 2666 .bpf_change_type = _bpf_change_type, 2667 .bpf_register_track_event = _bpf_register_track_event, 2668 .bpf_deregister_track_event = _bpf_deregister_track_event, 2669 2670 .bpf_mtap = _bpf_mtap, 2671 .bpf_mtap2 = _bpf_mtap2, 2672 .bpf_mtap_af = _bpf_mtap_af, 2673 .bpf_mtap_sl_in = _bpf_mtap_sl_in, 2674 .bpf_mtap_sl_out = _bpf_mtap_sl_out, 2675 2676 .bpf_mtap_softint = _bpf_mtap_softint, 2677 .bpf_mtap_softint_init = _bpf_mtap_softint_init, 2678 }; 2679 2680 MODULE(MODULE_CLASS_DRIVER, bpf, "bpf_filter"); 2681 2682 static int 2683 bpf_modcmd(modcmd_t cmd, void *arg) 2684 { 2685 #ifdef _MODULE 2686 devmajor_t bmajor, cmajor; 2687 #endif 2688 int error = 0; 2689 2690 switch (cmd) { 2691 case MODULE_CMD_INIT: 2692 bpf_init(); 2693 #ifdef _MODULE 2694 bmajor = cmajor = NODEVMAJOR; 2695 error = devsw_attach("bpf", NULL, &bmajor, 2696 &bpf_cdevsw, &cmajor); 2697 if (error) 2698 break; 2699 #endif 2700 2701 bpf_ops_handover_enter(&bpf_ops_kernel); 2702 atomic_swap_ptr(&bpf_ops, &bpf_ops_kernel); 2703 bpf_ops_handover_exit(); 2704 break; 2705 2706 case MODULE_CMD_FINI: 2707 /* 2708 * While there is no reference counting for bpf callers, 2709 * unload could at least in theory be done similarly to 2710 * system call disestablishment. This should even be 2711 * a little simpler: 2712 * 2713 * 1) replace op vector with stubs 2714 * 2) post update to all cpus with xc 2715 * 3) check that nobody is in bpf anymore 2716 * (it's doubtful we'd want something like l_sysent, 2717 * but we could do something like *signed* percpu 2718 * counters. if the sum is 0, we're good). 2719 * 4) if fail, unroll changes 2720 * 2721 * NOTE: change won't be atomic to the outside. some 2722 * packets may be not captured even if unload is 2723 * not successful. I think packet capture not working 2724 * is a perfectly logical consequence of trying to 2725 * disable packet capture. 2726 */ 2727 error = EOPNOTSUPP; 2728 break; 2729 2730 default: 2731 error = ENOTTY; 2732 break; 2733 } 2734 2735 return error; 2736 } 2737
Indexes created Fri Sep 26 20:09:58 GMT 2025