1 /*- 2 * Copyright (c) 2005 Pawel Jakub Dawidek <pjd@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include <sys/param.h> 31 #include <sys/systm.h> 32 #include <sys/kernel.h> 33 #include <sys/module.h> 34 #include <sys/lock.h> 35 #include <sys/mutex.h> 36 #include <sys/bio.h> 37 #include <sys/sysctl.h> 38 #include <sys/malloc.h> 39 #include <sys/kthread.h> 40 #include <sys/proc.h> 41 #include <sys/sched.h> 42 #include <sys/smp.h> 43 #include <sys/uio.h> 44 45 #include <vm/uma.h> 46 47 #include <geom/geom.h> 48 #include <geom/eli/g_eli.h> 49 #include <geom/eli/pkcs5v2.h> 50 51 52 MALLOC_DEFINE(M_ELI, "eli data", "GEOM_ELI Data"); 53 54 SYSCTL_DECL(_kern_geom); 55 SYSCTL_NODE(_kern_geom, OID_AUTO, eli, CTLFLAG_RW, 0, "GEOM_ELI stuff"); 56 u_int g_eli_debug = 0; 57 TUNABLE_INT("kern.geom.eli.debug", &g_eli_debug); 58 SYSCTL_UINT(_kern_geom_eli, OID_AUTO, debug, CTLFLAG_RW, &g_eli_debug, 0, 59 "Debug level"); 60 static u_int g_eli_tries = 3; 61 TUNABLE_INT("kern.geom.eli.tries", &g_eli_tries); 62 SYSCTL_UINT(_kern_geom_eli, OID_AUTO, tries, CTLFLAG_RW, &g_eli_tries, 0, 63 "Number of tries when asking for passphrase"); 64 static u_int g_eli_visible_passphrase = 0; 65 TUNABLE_INT("kern.geom.eli.visible_passphrase", &g_eli_visible_passphrase); 66 SYSCTL_UINT(_kern_geom_eli, OID_AUTO, visible_passphrase, CTLFLAG_RW, 67 &g_eli_visible_passphrase, 0, 68 "Turn on echo when entering passphrase (debug purposes only!!)"); 69 u_int g_eli_overwrites = 5; 70 SYSCTL_UINT(_kern_geom_eli, OID_AUTO, overwrites, CTLFLAG_RW, &g_eli_overwrites, 71 0, "Number of overwrites on-disk keys when destroying"); 72 static u_int g_eli_threads = 0; 73 TUNABLE_INT("kern.geom.eli.threads", &g_eli_threads); 74 SYSCTL_UINT(_kern_geom_eli, OID_AUTO, threads, CTLFLAG_RW, &g_eli_threads, 0, 75 "Number of threads doing crypto work"); 76 77 static int g_eli_do_taste = 0; 78 79 static int g_eli_destroy_geom(struct gctl_req *req, struct g_class *mp, 80 struct g_geom *gp); 81 static void g_eli_crypto_run(struct g_eli_worker *wr, struct bio *bp); 82 83 static g_taste_t g_eli_taste; 84 static g_dumpconf_t g_eli_dumpconf; 85 86 struct g_class g_eli_class = { 87 .name = G_ELI_CLASS_NAME, 88 .version = G_VERSION, 89 .ctlreq = g_eli_config, 90 .taste = g_eli_taste, 91 .destroy_geom = g_eli_destroy_geom 92 }; 93 94 95 /* 96 * Code paths: 97 * BIO_READ: 98 * g_eli_start -> g_io_request -> g_eli_read_done -> g_eli_crypto_run -> g_eli_crypto_read_done -> g_io_deliver 99 * BIO_WRITE: 100 * g_eli_start -> g_eli_crypto_run -> g_eli_crypto_write_done -> g_io_request -> g_eli_write_done -> g_io_deliver 101 */ 102 103 104 /* 105 * EAGAIN from crypto(9) means, that we were probably balanced to another crypto 106 * accelerator or something like this. 107 * The function updates the SID and rerun the operation. 108 */ 109 static int 110 g_eli_crypto_rerun(struct cryptop *crp) 111 { 112 struct g_eli_softc *sc; 113 struct g_eli_worker *wr; 114 struct bio *bp; 115 int error; 116 117 bp = (struct bio *)crp->crp_opaque; 118 sc = bp->bio_to->geom->softc; 119 LIST_FOREACH(wr, &sc->sc_workers, w_next) { 120 if (wr->w_number == bp->bio_pflags) 121 break; 122 } 123 KASSERT(wr != NULL, ("Invalid worker (%u).", bp->bio_pflags)); 124 G_ELI_DEBUG(1, "Reruning crypto %s request (sid: %ju -> %ju).", 125 bp->bio_cmd == BIO_READ ? "READ" : "WRITE", (uintmax_t)wr->w_sid, 126 (uintmax_t)crp->crp_sid); 127 wr->w_sid = crp->crp_sid; 128 crp->crp_etype = 0; 129 error = crypto_dispatch(crp); 130 if (error == 0) 131 return (0); 132 G_ELI_DEBUG(1, "%s: crypto_dispatch() returned %d.", __func__, error); 133 crp->crp_etype = error; 134 return (error); 135 } 136 137 /* 138 * The function is called afer reading encrypted data from the provider. 139 * 140 * g_eli_start -> g_io_request -> G_ELI_READ_DONE -> g_eli_crypto_run -> g_eli_crypto_read_done -> g_io_deliver 141 */ 142 static void 143 g_eli_read_done(struct bio *bp) 144 { 145 struct g_eli_softc *sc; 146 struct bio *pbp; 147 148 G_ELI_LOGREQ(2, bp, "Request done."); 149 pbp = bp->bio_parent; 150 if (pbp->bio_error == 0) 151 pbp->bio_error = bp->bio_error; 152 g_destroy_bio(bp); 153 if (pbp->bio_error != 0) { 154 G_ELI_LOGREQ(0, pbp, "%s() failed", __func__); 155 pbp->bio_completed = 0; 156 g_io_deliver(pbp, pbp->bio_error); 157 return; 158 } 159 sc = pbp->bio_to->geom->softc; 160 mtx_lock(&sc->sc_queue_mtx); 161 bioq_insert_tail(&sc->sc_queue, pbp); 162 mtx_unlock(&sc->sc_queue_mtx); 163 wakeup(sc); 164 } 165 166 /* 167 * The function is called after we read and decrypt data. 168 * 169 * g_eli_start -> g_io_request -> g_eli_read_done -> g_eli_crypto_run -> G_ELI_CRYPTO_READ_DONE -> g_io_deliver 170 */ 171 static int 172 g_eli_crypto_read_done(struct cryptop *crp) 173 { 174 struct bio *bp; 175 176 if (crp->crp_etype == EAGAIN) { 177 if (g_eli_crypto_rerun(crp) == 0) 178 return (0); 179 } 180 bp = (struct bio *)crp->crp_opaque; 181 bp->bio_inbed++; 182 if (crp->crp_etype == 0) { 183 G_ELI_DEBUG(3, "Crypto READ request done (%d/%d).", 184 bp->bio_inbed, bp->bio_children); 185 bp->bio_completed += crp->crp_olen; 186 } else { 187 G_ELI_DEBUG(1, "Crypto READ request failed (%d/%d) error=%d.", 188 bp->bio_inbed, bp->bio_children, crp->crp_etype); 189 if (bp->bio_error == 0) 190 bp->bio_error = crp->crp_etype; 191 } 192 /* 193 * Do we have all sectors already? 194 */ 195 if (bp->bio_inbed < bp->bio_children) 196 return (0); 197 free(bp->bio_driver2, M_ELI); 198 bp->bio_driver2 = NULL; 199 if (bp->bio_error != 0) { 200 G_ELI_LOGREQ(0, bp, "Crypto READ request failed (error=%d).", 201 bp->bio_error); 202 bp->bio_completed = 0; 203 } 204 /* 205 * Read is finished, send it up. 206 */ 207 g_io_deliver(bp, bp->bio_error); 208 return (0); 209 } 210 211 /* 212 * The function is called after we encrypt and write data. 213 * 214 * g_eli_start -> g_eli_crypto_run -> g_eli_crypto_write_done -> g_io_request -> G_ELI_WRITE_DONE -> g_io_deliver 215 */ 216 static void 217 g_eli_write_done(struct bio *bp) 218 { 219 struct bio *pbp; 220 221 G_ELI_LOGREQ(2, bp, "Request done."); 222 pbp = bp->bio_parent; 223 if (pbp->bio_error == 0) 224 pbp->bio_error = bp->bio_error; 225 free(pbp->bio_driver2, M_ELI); 226 pbp->bio_driver2 = NULL; 227 if (pbp->bio_error == 0) 228 pbp->bio_completed = pbp->bio_length; 229 else { 230 G_ELI_LOGREQ(0, pbp, "Crypto WRITE request failed (error=%d).", 231 pbp->bio_error); 232 pbp->bio_completed = 0; 233 } 234 g_destroy_bio(bp); 235 /* 236 * Write is finished, send it up. 237 */ 238 g_io_deliver(pbp, pbp->bio_error); 239 } 240 241 /* 242 * The function is called after data encryption. 243 * 244 * g_eli_start -> g_eli_crypto_run -> G_ELI_CRYPTO_WRITE_DONE -> g_io_request -> g_eli_write_done -> g_io_deliver 245 */ 246 static int 247 g_eli_crypto_write_done(struct cryptop *crp) 248 { 249 struct g_geom *gp; 250 struct g_consumer *cp; 251 struct bio *bp, *cbp; 252 253 if (crp->crp_etype == EAGAIN) { 254 if (g_eli_crypto_rerun(crp) == 0) 255 return (0); 256 } 257 bp = (struct bio *)crp->crp_opaque; 258 bp->bio_inbed++; 259 if (crp->crp_etype == 0) { 260 G_ELI_DEBUG(3, "Crypto WRITE request done (%d/%d).", 261 bp->bio_inbed, bp->bio_children); 262 } else { 263 G_ELI_DEBUG(1, "Crypto WRITE request failed (%d/%d) error=%d.", 264 bp->bio_inbed, bp->bio_children, crp->crp_etype); 265 if (bp->bio_error == 0) 266 bp->bio_error = crp->crp_etype; 267 } 268 /* 269 * All sectors are already encrypted? 270 */ 271 if (bp->bio_inbed < bp->bio_children) 272 return (0); 273 bp->bio_inbed = 0; 274 bp->bio_children = 1; 275 cbp = bp->bio_driver1; 276 bp->bio_driver1 = NULL; 277 if (bp->bio_error != 0) { 278 G_ELI_LOGREQ(0, bp, "Crypto WRITE request failed (error=%d).", 279 bp->bio_error); 280 free(bp->bio_driver2, M_ELI); 281 bp->bio_driver2 = NULL; 282 g_destroy_bio(cbp); 283 g_io_deliver(bp, bp->bio_error); 284 return (0); 285 } 286 cbp->bio_data = bp->bio_driver2; 287 cbp->bio_done = g_eli_write_done; 288 gp = bp->bio_to->geom; 289 cp = LIST_FIRST(&gp->consumer); 290 cbp->bio_to = cp->provider; 291 G_ELI_LOGREQ(2, cbp, "Sending request."); 292 /* 293 * Send encrypted data to the provider. 294 */ 295 g_io_request(cbp, cp); 296 return (0); 297 } 298 299 /* 300 * This function should never be called, but GEOM made as it set ->orphan() 301 * method for every geom. 302 */ 303 static void 304 g_eli_orphan_spoil_assert(struct g_consumer *cp) 305 { 306 307 panic("Function %s() called for %s.", __func__, cp->geom->name); 308 } 309 310 static void 311 g_eli_orphan(struct g_consumer *cp) 312 { 313 struct g_eli_softc *sc; 314 315 g_topology_assert(); 316 sc = cp->geom->softc; 317 if (sc == NULL) 318 return; 319 g_eli_destroy(sc, 1); 320 } 321 322 /* 323 * BIO_READ : G_ELI_START -> g_io_request -> g_eli_read_done -> g_eli_crypto_run -> g_eli_crypto_read_done -> g_io_deliver 324 * BIO_WRITE: G_ELI_START -> g_eli_crypto_run -> g_eli_crypto_write_done -> g_io_request -> g_eli_write_done -> g_io_deliver 325 */ 326 static void 327 g_eli_start(struct bio *bp) 328 { 329 struct g_eli_softc *sc; 330 struct bio *cbp; 331 332 sc = bp->bio_to->geom->softc; 333 KASSERT(sc != NULL, 334 ("Provider's error should be set (error=%d)(device=%s).", 335 bp->bio_to->error, bp->bio_to->name)); 336 G_ELI_LOGREQ(2, bp, "Request received."); 337 338 switch (bp->bio_cmd) { 339 case BIO_READ: 340 case BIO_WRITE: 341 break; 342 case BIO_DELETE: 343 /* 344 * We could eventually support BIO_DELETE request. 345 * It could be done by overwritting requested sector with 346 * random data g_eli_overwrites number of times. 347 */ 348 case BIO_GETATTR: 349 default: 350 g_io_deliver(bp, EOPNOTSUPP); 351 return; 352 } 353 cbp = g_clone_bio(bp); 354 if (cbp == NULL) { 355 g_io_deliver(bp, ENOMEM); 356 return; 357 } 358 if (bp->bio_cmd == BIO_READ) { 359 struct g_consumer *cp; 360 361 cbp->bio_done = g_eli_read_done; 362 cp = LIST_FIRST(&sc->sc_geom->consumer); 363 cbp->bio_to = cp->provider; 364 G_ELI_LOGREQ(2, bp, "Sending request."); 365 /* 366 * Read encrypted data from provider. 367 */ 368 g_io_request(cbp, cp); 369 } else /* if (bp->bio_cmd == BIO_WRITE) */ { 370 bp->bio_driver1 = cbp; 371 mtx_lock(&sc->sc_queue_mtx); 372 bioq_insert_tail(&sc->sc_queue, bp); 373 mtx_unlock(&sc->sc_queue_mtx); 374 wakeup(sc); 375 } 376 } 377 378 /* 379 * This is the main function for kernel worker thread when we don't have 380 * hardware acceleration and we have to do cryptography in software. 381 * Dedicated thread is needed, so we don't slow down g_up/g_down GEOM 382 * threads with crypto work. 383 */ 384 static void 385 g_eli_worker(void *arg) 386 { 387 struct g_eli_softc *sc; 388 struct g_eli_worker *wr; 389 struct bio *bp; 390 391 wr = arg; 392 sc = wr->w_softc; 393 mtx_lock_spin(&sched_lock); 394 sched_prio(curthread, PRIBIO); 395 if (sc->sc_crypto == G_ELI_CRYPTO_SW && g_eli_threads == 0) 396 sched_bind(curthread, wr->w_number); 397 mtx_unlock_spin(&sched_lock); 398 399 G_ELI_DEBUG(1, "Thread %s started.", curthread->td_proc->p_comm); 400 401 for (;;) { 402 mtx_lock(&sc->sc_queue_mtx); 403 bp = bioq_takefirst(&sc->sc_queue); 404 if (bp == NULL) { 405 if ((sc->sc_flags & G_ELI_FLAG_DESTROY) != 0) { 406 LIST_REMOVE(wr, w_next); 407 crypto_freesession(wr->w_sid); 408 free(wr, M_ELI); 409 G_ELI_DEBUG(1, "Thread %s exiting.", 410 curthread->td_proc->p_comm); 411 wakeup(&sc->sc_workers); 412 mtx_unlock(&sc->sc_queue_mtx); 413 kthread_exit(0); 414 } 415 msleep(sc, &sc->sc_queue_mtx, PRIBIO | PDROP, 416 "geli:w", 0); 417 continue; 418 } 419 mtx_unlock(&sc->sc_queue_mtx); 420 g_eli_crypto_run(wr, bp); 421 } 422 } 423 424 /* 425 * Here we generate IV. It is unique for every sector. 426 */ 427 static void 428 g_eli_crypto_ivgen(struct g_eli_softc *sc, off_t offset, u_char *iv, 429 size_t size) 430 { 431 u_char hash[SHA256_DIGEST_LENGTH]; 432 SHA256_CTX ctx; 433 434 /* Copy precalculated SHA256 context for IV-Key. */ 435 bcopy(&sc->sc_ivctx, &ctx, sizeof(ctx)); 436 SHA256_Update(&ctx, (uint8_t *)&offset, sizeof(offset)); 437 SHA256_Final(hash, &ctx); 438 bcopy(hash, iv, size); 439 } 440 441 /* 442 * This is the main function responsible for cryptography (ie. communication 443 * with crypto(9) subsystem). 444 */ 445 static void 446 g_eli_crypto_run(struct g_eli_worker *wr, struct bio *bp) 447 { 448 struct g_eli_softc *sc; 449 struct cryptop *crp; 450 struct cryptodesc *crd; 451 struct uio *uio; 452 struct iovec *iov; 453 u_int i, nsec, add, secsize; 454 int err, error, flags; 455 size_t size; 456 u_char *p, *data; 457 458 G_ELI_LOGREQ(3, bp, "%s", __func__); 459 460 bp->bio_pflags = wr->w_number; 461 sc = wr->w_softc; 462 secsize = LIST_FIRST(&sc->sc_geom->provider)->sectorsize; 463 nsec = bp->bio_length / secsize; 464 465 /* 466 * Calculate how much memory do we need. 467 * We need separate crypto operation for every single sector. 468 * It is much faster to calculate total amount of needed memory here and 469 * do the allocation once insteaf of allocate memory in pieces (many, 470 * many pieces). 471 */ 472 size = sizeof(*crp) * nsec; 473 size += sizeof(*crd) * nsec; 474 size += sizeof(*uio) * nsec; 475 size += sizeof(*iov) * nsec; 476 /* 477 * If we write the data we cannot destroy current bio_data content, 478 * so we need to allocate more memory for encrypted data. 479 */ 480 if (bp->bio_cmd == BIO_WRITE) 481 size += bp->bio_length; 482 p = malloc(size, M_ELI, M_WAITOK); 483 484 bp->bio_inbed = 0; 485 bp->bio_children = nsec; 486 bp->bio_driver2 = p; 487 488 if (bp->bio_cmd == BIO_READ) 489 data = bp->bio_data; 490 else { 491 data = p; 492 p += bp->bio_length; 493 bcopy(bp->bio_data, data, bp->bio_length); 494 } 495 496 error = 0; 497 for (i = 0, add = 0; i < nsec; i++, add += secsize) { 498 crp = (struct cryptop *)p; p += sizeof(*crp); 499 crd = (struct cryptodesc *)p; p += sizeof(*crd); 500 uio = (struct uio *)p; p += sizeof(*uio); 501 iov = (struct iovec *)p; p += sizeof(*iov); 502 503 iov->iov_len = secsize; 504 iov->iov_base = data; 505 data += secsize; 506 507 uio->uio_iov = iov; 508 uio->uio_iovcnt = 1; 509 uio->uio_segflg = UIO_SYSSPACE; 510 uio->uio_resid = secsize; 511 512 crp->crp_sid = wr->w_sid; 513 crp->crp_ilen = secsize; 514 crp->crp_olen = secsize; 515 crp->crp_opaque = (void *)bp; 516 crp->crp_buf = (void *)uio; 517 if (bp->bio_cmd == BIO_WRITE) 518 crp->crp_callback = g_eli_crypto_write_done; 519 else /* if (bp->bio_cmd == BIO_READ) */ 520 crp->crp_callback = g_eli_crypto_read_done; 521 crp->crp_flags = CRYPTO_F_IOV | CRYPTO_F_CBIFSYNC | CRYPTO_F_REL; 522 crp->crp_desc = crd; 523 524 crd->crd_skip = 0; 525 crd->crd_len = secsize; 526 crd->crd_flags = flags; 527 crd->crd_flags = 528 CRD_F_IV_EXPLICIT | CRD_F_IV_PRESENT | CRD_F_KEY_EXPLICIT; 529 if (bp->bio_cmd == BIO_WRITE) 530 crd->crd_flags |= CRD_F_ENCRYPT; 531 crd->crd_alg = sc->sc_algo; 532 crd->crd_key = sc->sc_datakey; 533 crd->crd_klen = sc->sc_keylen; 534 g_eli_crypto_ivgen(sc, bp->bio_offset + add, crd->crd_iv, 535 sizeof(crd->crd_iv)); 536 crd->crd_next = NULL; 537 538 crp->crp_etype = 0; 539 err = crypto_dispatch(crp); 540 if (error == 0) 541 error = err; 542 } 543 if (bp->bio_error == 0) 544 bp->bio_error = error; 545 } 546 547 int 548 g_eli_read_metadata(struct g_class *mp, struct g_provider *pp, 549 struct g_eli_metadata *md) 550 { 551 struct g_geom *gp; 552 struct g_consumer *cp; 553 u_char *buf = NULL; 554 int error; 555 556 g_topology_assert(); 557 558 gp = g_new_geomf(mp, "eli:taste"); 559 gp->start = g_eli_start; 560 gp->access = g_std_access; 561 /* 562 * g_eli_read_metadata() is always called from the event thread. 563 * Our geom is created and destroyed in the same event, so there 564 * could be no orphan nor spoil event in the meantime. 565 */ 566 gp->orphan = g_eli_orphan_spoil_assert; 567 gp->spoiled = g_eli_orphan_spoil_assert; 568 cp = g_new_consumer(gp); 569 error = g_attach(cp, pp); 570 if (error != 0) 571 goto end; 572 error = g_access(cp, 1, 0, 0); 573 if (error != 0) 574 goto end; 575 g_topology_unlock(); 576 buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize, 577 &error); 578 g_topology_lock(); 579 if (buf == NULL) 580 goto end; 581 eli_metadata_decode(buf, md); 582 end: 583 if (buf != NULL) 584 g_free(buf); 585 if (cp->provider != NULL) { 586 if (cp->acr == 1) 587 g_access(cp, -1, 0, 0); 588 g_detach(cp); 589 } 590 g_destroy_consumer(cp); 591 g_destroy_geom(gp); 592 return (error); 593 } 594 595 /* 596 * The function is called when we had last close on provider and user requested 597 * to close it when this situation occur. 598 */ 599 static void 600 g_eli_last_close(struct g_eli_softc *sc) 601 { 602 struct g_geom *gp; 603 struct g_provider *pp; 604 char ppname[64]; 605 int error; 606 607 g_topology_assert(); 608 gp = sc->sc_geom; 609 pp = LIST_FIRST(&gp->provider); 610 strlcpy(ppname, pp->name, sizeof(ppname)); 611 error = g_eli_destroy(sc, 1); 612 KASSERT(error == 0, ("Cannot detach %s on last close (error=%d).", 613 ppname, error)); 614 G_ELI_DEBUG(0, "Detached %s on last close.", ppname); 615 } 616 617 int 618 g_eli_access(struct g_provider *pp, int dr, int dw, int de) 619 { 620 struct g_eli_softc *sc; 621 struct g_geom *gp; 622 623 gp = pp->geom; 624 sc = gp->softc; 625 626 if (dw > 0) { 627 /* Someone is opening us for write, we need to remember that. */ 628 sc->sc_flags |= G_ELI_FLAG_WOPEN; 629 return (0); 630 } 631 /* Is this the last close? */ 632 if (pp->acr + dr > 0 || pp->acw + dw > 0 || pp->ace + de > 0) 633 return (0); 634 635 /* 636 * Automatically detach on last close if requested. 637 */ 638 if ((sc->sc_flags & G_ELI_FLAG_RW_DETACH) || 639 (sc->sc_flags & G_ELI_FLAG_WOPEN)) { 640 g_eli_last_close(sc); 641 } 642 return (0); 643 } 644 645 struct g_geom * 646 g_eli_create(struct gctl_req *req, struct g_class *mp, struct g_provider *bpp, 647 const struct g_eli_metadata *md, const u_char *mkey, int nkey) 648 { 649 struct g_eli_softc *sc; 650 struct g_eli_worker *wr; 651 struct g_geom *gp; 652 struct g_provider *pp; 653 struct g_consumer *cp; 654 struct cryptoini cri; 655 u_int i, threads; 656 int error; 657 658 G_ELI_DEBUG(1, "Creating device %s%s.", bpp->name, G_ELI_SUFFIX); 659 660 gp = g_new_geomf(mp, "%s%s", bpp->name, G_ELI_SUFFIX); 661 gp->softc = NULL; /* for a moment */ 662 663 sc = malloc(sizeof(*sc), M_ELI, M_WAITOK | M_ZERO); 664 gp->start = g_eli_start; 665 /* 666 * Spoiling cannot happen actually, because we keep provider open for 667 * writing all the time. 668 */ 669 gp->spoiled = g_eli_orphan_spoil_assert; 670 gp->orphan = g_eli_orphan; 671 /* 672 * If detach-on-last-close feature is not enabled, we can simply use 673 * g_std_access(). 674 */ 675 if (md->md_flags & G_ELI_FLAG_WO_DETACH) 676 gp->access = g_eli_access; 677 else 678 gp->access = g_std_access; 679 gp->dumpconf = g_eli_dumpconf; 680 681 sc->sc_crypto = G_ELI_CRYPTO_SW; 682 sc->sc_flags = md->md_flags; 683 sc->sc_algo = md->md_algo; 684 sc->sc_nkey = nkey; 685 /* 686 * Remember the keys in our softc structure. 687 */ 688 bcopy(mkey, sc->sc_ivkey, sizeof(sc->sc_ivkey)); 689 mkey += sizeof(sc->sc_ivkey); 690 bcopy(mkey, sc->sc_datakey, sizeof(sc->sc_datakey)); 691 sc->sc_keylen = md->md_keylen; 692 693 /* 694 * Precalculate SHA256 for IV generation. 695 * This is expensive operation and we can do it only once now or for 696 * every access to sector, so now will be much better. 697 */ 698 SHA256_Init(&sc->sc_ivctx); 699 SHA256_Update(&sc->sc_ivctx, sc->sc_ivkey, sizeof(sc->sc_ivkey)); 700 701 gp->softc = sc; 702 sc->sc_geom = gp; 703 704 bioq_init(&sc->sc_queue); 705 mtx_init(&sc->sc_queue_mtx, "geli:queue", NULL, MTX_DEF); 706 707 pp = NULL; 708 cp = g_new_consumer(gp); 709 error = g_attach(cp, bpp); 710 if (error != 0) { 711 if (req != NULL) { 712 gctl_error(req, "Cannot attach to %s (error=%d).", 713 bpp->name, error); 714 } else { 715 G_ELI_DEBUG(1, "Cannot attach to %s (error=%d).", 716 bpp->name, error); 717 } 718 goto failed; 719 } 720 /* 721 * Keep provider open all the time, so we can run critical tasks, 722 * like Master Keys deletion, without wondering if we can open 723 * provider or not. 724 */ 725 error = g_access(cp, 1, 1, 1); 726 if (error != 0) { 727 if (req != NULL) { 728 gctl_error(req, "Cannot access %s (error=%d).", 729 bpp->name, error); 730 } else { 731 G_ELI_DEBUG(1, "Cannot access %s (error=%d).", 732 bpp->name, error); 733 } 734 goto failed; 735 } 736 737 LIST_INIT(&sc->sc_workers); 738 739 bzero(&cri, sizeof(cri)); 740 cri.cri_alg = sc->sc_algo; 741 cri.cri_klen = sc->sc_keylen; 742 cri.cri_key = sc->sc_datakey; 743 744 threads = g_eli_threads; 745 if (threads == 0) 746 threads = mp_ncpus; 747 else if (threads > mp_ncpus) { 748 /* There is really no need for too many worker threads. */ 749 threads = mp_ncpus; 750 G_ELI_DEBUG(0, "Reducing number of threads to %u.", threads); 751 } 752 for (i = 0; i < threads; i++) { 753 wr = malloc(sizeof(*wr), M_ELI, M_WAITOK | M_ZERO); 754 wr->w_softc = sc; 755 wr->w_number = i; 756 757 /* 758 * If this is the first pass, try to get hardware support. 759 * Use software cryptography, if we cannot get it. 760 */ 761 if (i == 0) { 762 error = crypto_newsession(&wr->w_sid, &cri, 1); 763 if (error == 0) 764 sc->sc_crypto = G_ELI_CRYPTO_HW; 765 } 766 if (sc->sc_crypto == G_ELI_CRYPTO_SW) 767 error = crypto_newsession(&wr->w_sid, &cri, 0); 768 if (error != 0) { 769 free(wr, M_ELI); 770 if (req != NULL) { 771 gctl_error(req, "Cannot setup crypto session " 772 "for %s (error=%d).", bpp->name, error); 773 } else { 774 G_ELI_DEBUG(1, "Cannot setup crypto session " 775 "for %s (error=%d).", bpp->name, error); 776 } 777 goto failed; 778 } 779 780 error = kthread_create(g_eli_worker, wr, &wr->w_proc, 0, 0, 781 "g_eli[%u] %s", i, bpp->name); 782 if (error != 0) { 783 crypto_freesession(wr->w_sid); 784 free(wr, M_ELI); 785 if (req != NULL) { 786 gctl_error(req, "Cannot create kernel thread " 787 "for %s (error=%d).", bpp->name, error); 788 } else { 789 G_ELI_DEBUG(1, "Cannot create kernel thread " 790 "for %s (error=%d).", bpp->name, error); 791 } 792 goto failed; 793 } 794 LIST_INSERT_HEAD(&sc->sc_workers, wr, w_next); 795 /* If we have hardware support, one thread is enough. */ 796 if (sc->sc_crypto == G_ELI_CRYPTO_HW) 797 break; 798 } 799 800 /* 801 * Create decrypted provider. 802 */ 803 pp = g_new_providerf(gp, "%s%s", bpp->name, G_ELI_SUFFIX); 804 pp->sectorsize = md->md_sectorsize; 805 pp->mediasize = bpp->mediasize; 806 if ((sc->sc_flags & G_ELI_FLAG_ONETIME) == 0) 807 pp->mediasize -= bpp->sectorsize; 808 pp->mediasize -= (pp->mediasize % pp->sectorsize); 809 g_error_provider(pp, 0); 810 811 G_ELI_DEBUG(0, "Device %s created.", pp->name); 812 G_ELI_DEBUG(0, " Cipher: %s", g_eli_algo2str(sc->sc_algo)); 813 G_ELI_DEBUG(0, "Key length: %u", sc->sc_keylen); 814 G_ELI_DEBUG(0, " Crypto: %s", 815 sc->sc_crypto == G_ELI_CRYPTO_SW ? "software" : "hardware"); 816 return (gp); 817 failed: 818 mtx_lock(&sc->sc_queue_mtx); 819 sc->sc_flags |= G_ELI_FLAG_DESTROY; 820 wakeup(sc); 821 /* 822 * Wait for kernel threads self destruction. 823 */ 824 while (!LIST_EMPTY(&sc->sc_workers)) { 825 msleep(&sc->sc_workers, &sc->sc_queue_mtx, PRIBIO, 826 "geli:destroy", 0); 827 } 828 mtx_destroy(&sc->sc_queue_mtx); 829 if (cp->provider != NULL) { 830 if (cp->acr == 1) 831 g_access(cp, -1, -1, -1); 832 g_detach(cp); 833 } 834 g_destroy_consumer(cp); 835 if (pp != NULL) 836 g_destroy_provider(pp); 837 g_destroy_geom(gp); 838 bzero(sc, sizeof(*sc)); 839 free(sc, M_ELI); 840 return (NULL); 841 } 842 843 int 844 g_eli_destroy(struct g_eli_softc *sc, boolean_t force) 845 { 846 struct g_geom *gp; 847 struct g_provider *pp; 848 849 g_topology_assert(); 850 851 if (sc == NULL) 852 return (ENXIO); 853 854 gp = sc->sc_geom; 855 pp = LIST_FIRST(&gp->provider); 856 if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) { 857 if (force) { 858 G_ELI_DEBUG(1, "Device %s is still open, so it " 859 "can't be definitely removed.", pp->name); 860 } else { 861 G_ELI_DEBUG(1, 862 "Device %s is still open (r%dw%de%d).", pp->name, 863 pp->acr, pp->acw, pp->ace); 864 return (EBUSY); 865 } 866 } 867 868 mtx_lock(&sc->sc_queue_mtx); 869 sc->sc_flags |= G_ELI_FLAG_DESTROY; 870 wakeup(sc); 871 while (!LIST_EMPTY(&sc->sc_workers)) { 872 msleep(&sc->sc_workers, &sc->sc_queue_mtx, PRIBIO, 873 "geli:destroy", 0); 874 } 875 mtx_destroy(&sc->sc_queue_mtx); 876 gp->softc = NULL; 877 bzero(sc, sizeof(*sc)); 878 free(sc, M_ELI); 879 880 if (pp == NULL || (pp->acr == 0 && pp->acw == 0 && pp->ace == 0)) 881 G_ELI_DEBUG(0, "Device %s destroyed.", gp->name); 882 g_wither_geom_close(gp, ENXIO); 883 884 return (0); 885 } 886 887 static int 888 g_eli_destroy_geom(struct gctl_req *req __unused, 889 struct g_class *mp __unused, struct g_geom *gp) 890 { 891 struct g_eli_softc *sc; 892 893 sc = gp->softc; 894 return (g_eli_destroy(sc, 0)); 895 } 896 897 /* 898 * Tasting is only made on boot. 899 * We detect providers which should be attached before root is mounted. 900 */ 901 static struct g_geom * 902 g_eli_taste(struct g_class *mp, struct g_provider *pp, int flags __unused) 903 { 904 struct g_eli_metadata md; 905 struct g_geom *gp; 906 struct hmac_ctx ctx; 907 char passphrase[256]; 908 u_char key[G_ELI_USERKEYLEN], mkey[G_ELI_DATAIVKEYLEN]; 909 u_int nkey, i; 910 int error; 911 912 g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name); 913 g_topology_assert(); 914 915 if (!g_eli_do_taste || g_eli_tries == 0) 916 return (NULL); 917 918 G_ELI_DEBUG(3, "Tasting %s.", pp->name); 919 920 error = g_eli_read_metadata(mp, pp, &md); 921 if (error != 0) 922 return (NULL); 923 gp = NULL; 924 925 if (strcmp(md.md_magic, G_ELI_MAGIC) != 0) 926 return (NULL); 927 if (md.md_version > G_ELI_VERSION) { 928 printf("geom_eli.ko module is too old to handle %s.\n", 929 pp->name); 930 return (NULL); 931 } 932 if (md.md_provsize != pp->mediasize) 933 return (NULL); 934 /* Should we attach it on boot? */ 935 if ((md.md_flags & G_ELI_FLAG_BOOT) == 0) 936 return (NULL); 937 if (md.md_keys == 0x00) { 938 G_ELI_DEBUG(0, "No valid keys on %s.", pp->name); 939 return (NULL); 940 } 941 942 /* 943 * Ask for the passphrase no more than g_eli_tries times. 944 */ 945 for (i = 0; i < g_eli_tries; i++) { 946 printf("Enter passphrase for %s: ", pp->name); 947 gets(passphrase, sizeof(passphrase), g_eli_visible_passphrase); 948 KASSERT(md.md_iterations >= 0, ("md_iterations = %d for %s", 949 (int)md.md_iterations, pp->name)); 950 /* 951 * Prepare Derived-Key from the user passphrase. 952 */ 953 g_eli_crypto_hmac_init(&ctx, NULL, 0); 954 if (md.md_iterations == 0) { 955 g_eli_crypto_hmac_update(&ctx, md.md_salt, 956 sizeof(md.md_salt)); 957 g_eli_crypto_hmac_update(&ctx, passphrase, 958 strlen(passphrase)); 959 } else { 960 u_char dkey[G_ELI_USERKEYLEN]; 961 962 pkcs5v2_genkey(dkey, sizeof(dkey), md.md_salt, 963 sizeof(md.md_salt), passphrase, md.md_iterations); 964 g_eli_crypto_hmac_update(&ctx, dkey, sizeof(dkey)); 965 bzero(dkey, sizeof(dkey)); 966 } 967 g_eli_crypto_hmac_final(&ctx, key, 0); 968 969 /* 970 * Decrypt Master-Key. 971 */ 972 error = g_eli_mkey_decrypt(&md, key, mkey, &nkey); 973 bzero(key, sizeof(key)); 974 if (error == -1) { 975 if (i == g_eli_tries - 1) { 976 i++; 977 break; 978 } 979 G_ELI_DEBUG(0, "Wrong key for %s. Tries left: %u.", 980 pp->name, g_eli_tries - i - 1); 981 /* Try again. */ 982 continue; 983 } else if (error > 0) { 984 G_ELI_DEBUG(0, "Cannot decrypt Master Key for %s (error=%d).", 985 pp->name, error); 986 return (NULL); 987 } 988 G_ELI_DEBUG(1, "Using Master Key %u for %s.", nkey, pp->name); 989 break; 990 } 991 if (i == g_eli_tries) { 992 G_ELI_DEBUG(0, "Wrong key for %s. No tries left.", pp->name); 993 return (NULL); 994 } 995 996 /* 997 * We have correct key, let's attach provider. 998 */ 999 gp = g_eli_create(NULL, mp, pp, &md, mkey, nkey); 1000 bzero(mkey, sizeof(mkey)); 1001 bzero(&md, sizeof(md)); 1002 if (gp == NULL) { 1003 G_ELI_DEBUG(0, "Cannot create device %s%s.", pp->name, 1004 G_ELI_SUFFIX); 1005 return (NULL); 1006 } 1007 return (gp); 1008 } 1009 1010 static void 1011 g_eli_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, 1012 struct g_consumer *cp, struct g_provider *pp) 1013 { 1014 struct g_eli_softc *sc; 1015 1016 g_topology_assert(); 1017 sc = gp->softc; 1018 if (sc == NULL) 1019 return; 1020 if (pp != NULL || cp != NULL) 1021 return; /* Nothing here. */ 1022 sbuf_printf(sb, "%s<Flags>", indent); 1023 if (sc->sc_flags == 0) 1024 sbuf_printf(sb, "NONE"); 1025 else { 1026 int first = 1; 1027 1028 #define ADD_FLAG(flag, name) do { \ 1029 if ((sc->sc_flags & (flag)) != 0) { \ 1030 if (!first) \ 1031 sbuf_printf(sb, ", "); \ 1032 else \ 1033 first = 0; \ 1034 sbuf_printf(sb, name); \ 1035 } \ 1036 } while (0) 1037 ADD_FLAG(G_ELI_FLAG_ONETIME, "ONETIME"); 1038 ADD_FLAG(G_ELI_FLAG_BOOT, "BOOT"); 1039 ADD_FLAG(G_ELI_FLAG_WO_DETACH, "W-DETACH"); 1040 ADD_FLAG(G_ELI_FLAG_RW_DETACH, "RW-DETACH"); 1041 ADD_FLAG(G_ELI_FLAG_WOPEN, "W-OPEN"); 1042 ADD_FLAG(G_ELI_FLAG_DESTROY, "DESTROY"); 1043 #undef ADD_FLAG 1044 } 1045 sbuf_printf(sb, "</Flags>\n"); 1046 1047 if ((sc->sc_flags & G_ELI_FLAG_ONETIME) == 0) { 1048 sbuf_printf(sb, "%s<UsedKey>%u</UsedKey>\n", indent, 1049 sc->sc_nkey); 1050 } 1051 sbuf_printf(sb, "%s<Crypto>", indent); 1052 switch (sc->sc_crypto) { 1053 case G_ELI_CRYPTO_HW: 1054 sbuf_printf(sb, "hardware"); 1055 break; 1056 case G_ELI_CRYPTO_SW: 1057 sbuf_printf(sb, "software"); 1058 break; 1059 default: 1060 sbuf_printf(sb, "UNKNOWN"); 1061 break; 1062 } 1063 sbuf_printf(sb, "</Crypto>\n"); 1064 sbuf_printf(sb, "%s<KeyLength>%u</KeyLength>\n", indent, sc->sc_keylen); 1065 sbuf_printf(sb, "%s<Cipher>%s</Cipher>\n", indent, 1066 g_eli_algo2str(sc->sc_algo)); 1067 } 1068 1069 static void 1070 g_eli_on_boot_start(void *dummy __unused) 1071 { 1072 1073 /* This prevents from tasting when module is loaded after boot. */ 1074 if (cold) { 1075 G_ELI_DEBUG(1, "Start tasting."); 1076 g_eli_do_taste = 1; 1077 } else { 1078 G_ELI_DEBUG(1, "Tasting not started."); 1079 } 1080 } 1081 SYSINIT(geli_boot_start, SI_SUB_TUNABLES, SI_ORDER_ANY, g_eli_on_boot_start, NULL) 1082 1083 static void 1084 g_eli_on_boot_end(void *dummy __unused) 1085 { 1086 1087 if (g_eli_do_taste) { 1088 G_ELI_DEBUG(1, "Tasting no more."); 1089 g_eli_do_taste = 0; 1090 } 1091 } 1092 SYSINIT(geli_boot_end, SI_SUB_RUN_SCHEDULER, SI_ORDER_ANY, g_eli_on_boot_end, NULL) 1093 1094 DECLARE_GEOM_CLASS(g_eli_class, g_eli); 1095 MODULE_DEPEND(geom_eli, crypto, 1, 1, 1); 1096