sys/geom/eli/g_eli.c

   1 /*-
   2  * Copyright (c) 2005-2011 Pawel Jakub Dawidek <pawel@dawidek.net>
   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/cons.h>
  33 #include <sys/kernel.h>
  34 #include <sys/linker.h>
  35 #include <sys/module.h>
  36 #include <sys/lock.h>
  37 #include <sys/mutex.h>
  38 #include <sys/bio.h>
  39 #include <sys/sbuf.h>
  40 #include <sys/sysctl.h>
  41 #include <sys/malloc.h>
  42 #include <sys/eventhandler.h>
  43 #include <sys/kthread.h>
  44 #include <sys/proc.h>
  45 #include <sys/sched.h>
  46 #include <sys/smp.h>
  47 #include <sys/uio.h>
  48 #include <sys/vnode.h>
  49
  50 #include <vm/uma.h>
  51
  52 #include <geom/geom.h>
  53 #include <geom/eli/g_eli.h>
  54 #include <geom/eli/pkcs5v2.h>
  55
  56 FEATURE(geom_eli, "GEOM crypto module");
  57
  58 MALLOC_DEFINE(M_ELI, "eli data", "GEOM_ELI Data");
  59
  60 SYSCTL_DECL(_kern_geom);
  61 SYSCTL_NODE(_kern_geom, OID_AUTO, eli, CTLFLAG_RW, 0, "GEOM_ELI stuff");
  62 static int g_eli_version = G_ELI_VERSION;
  63 SYSCTL_INT(_kern_geom_eli, OID_AUTO, version, CTLFLAG_RD, &g_eli_version, 0,
  64     "GELI version");
  65 int g_eli_debug = 0;
  66 TUNABLE_INT("kern.geom.eli.debug", &g_eli_debug);
  67 SYSCTL_INT(_kern_geom_eli, OID_AUTO, debug, CTLFLAG_RW, &g_eli_debug, 0,
  68     "Debug level");
  69 static u_int g_eli_tries = 3;
  70 TUNABLE_INT("kern.geom.eli.tries", &g_eli_tries);
  71 SYSCTL_UINT(_kern_geom_eli, OID_AUTO, tries, CTLFLAG_RW, &g_eli_tries, 0,
  72     "Number of tries for entering the passphrase");
  73 static u_int g_eli_visible_passphrase = GETS_NOECHO;
  74 TUNABLE_INT("kern.geom.eli.visible_passphrase", &g_eli_visible_passphrase);
  75 SYSCTL_UINT(_kern_geom_eli, OID_AUTO, visible_passphrase, CTLFLAG_RW,
  76     &g_eli_visible_passphrase, 0,
  77     "Visibility of passphrase prompt (0 = invisible, 1 = visible, 2 = asterisk)");
  78 u_int g_eli_overwrites = G_ELI_OVERWRITES;
  79 TUNABLE_INT("kern.geom.eli.overwrites", &g_eli_overwrites);
  80 SYSCTL_UINT(_kern_geom_eli, OID_AUTO, overwrites, CTLFLAG_RW, &g_eli_overwrites,
  81     0, "Number of times on-disk keys should be overwritten when destroying them");
  82 static u_int g_eli_threads = 0;
  83 TUNABLE_INT("kern.geom.eli.threads", &g_eli_threads);
  84 SYSCTL_UINT(_kern_geom_eli, OID_AUTO, threads, CTLFLAG_RW, &g_eli_threads, 0,
  85     "Number of threads doing crypto work");
  86 u_int g_eli_batch = 0;
  87 TUNABLE_INT("kern.geom.eli.batch", &g_eli_batch);
  88 SYSCTL_UINT(_kern_geom_eli, OID_AUTO, batch, CTLFLAG_RW, &g_eli_batch, 0,
  89     "Use crypto operations batching");
  90
  91 static eventhandler_tag g_eli_pre_sync = NULL;
  92
  93 static int g_eli_destroy_geom(struct gctl_req *req, struct g_class *mp,
  94     struct g_geom *gp);
  95 static void g_eli_init(struct g_class *mp);
  96 static void g_eli_fini(struct g_class *mp);
  97
  98 static g_taste_t g_eli_taste;
  99 static g_dumpconf_t g_eli_dumpconf;
 100
 101 struct g_class g_eli_class = {
 102         .name = G_ELI_CLASS_NAME,
 103         .version = G_VERSION,
 104         .ctlreq = g_eli_config,
 105         .taste = g_eli_taste,
 106         .destroy_geom = g_eli_destroy_geom,
 107         .init = g_eli_init,
 108         .fini = g_eli_fini
 109 };
 110
 111
 112 /*
 113  * Code paths:
 114  * BIO_READ:
 115  *      g_eli_start -> g_eli_crypto_read -> g_io_request -> g_eli_read_done -> g_eli_crypto_run -> g_eli_crypto_read_done -> g_io_deliver
 116  * BIO_WRITE:
 117  *      g_eli_start -> g_eli_crypto_run -> g_eli_crypto_write_done -> g_io_request -> g_eli_write_done -> g_io_deliver
 118  */
 119
 120
 121 /*
 122  * EAGAIN from crypto(9) means, that we were probably balanced to another crypto
 123  * accelerator or something like this.
 124  * The function updates the SID and rerun the operation.
 125  */
 126 int
 127 g_eli_crypto_rerun(struct cryptop *crp)
 128 {
 129         struct g_eli_softc *sc;
 130         struct g_eli_worker *wr;
 131         struct bio *bp;
 132         int error;
 133
 134         bp = (struct bio *)crp->crp_opaque;
 135         sc = bp->bio_to->geom->softc;
 136         LIST_FOREACH(wr, &sc->sc_workers, w_next) {
 137                 if (wr->w_number == bp->bio_pflags)
 138                         break;
 139         }
 140         KASSERT(wr != NULL, ("Invalid worker (%u).", bp->bio_pflags));
 141         G_ELI_DEBUG(1, "Rerunning crypto %s request (sid: %ju -> %ju).",
 142             bp->bio_cmd == BIO_READ ? "READ" : "WRITE", (uintmax_t)wr->w_sid,
 143             (uintmax_t)crp->crp_sid);
 144         wr->w_sid = crp->crp_sid;
 145         crp->crp_etype = 0;
 146         error = crypto_dispatch(crp);
 147         if (error == 0)
 148                 return (0);
 149         G_ELI_DEBUG(1, "%s: crypto_dispatch() returned %d.", __func__, error);
 150         crp->crp_etype = error;
 151         return (error);
 152 }
 153
 154 /*
 155  * The function is called afer reading encrypted data from the provider.
 156  *
 157  * g_eli_start -> g_eli_crypto_read -> g_io_request -> G_ELI_READ_DONE -> g_eli_crypto_run -> g_eli_crypto_read_done -> g_io_deliver
 158  */
 159 void
 160 g_eli_read_done(struct bio *bp)
 161 {
 162         struct g_eli_softc *sc;
 163         struct bio *pbp;
 164
 165         G_ELI_LOGREQ(2, bp, "Request done.");
 166         pbp = bp->bio_parent;
 167         if (pbp->bio_error == 0)
 168                 pbp->bio_error = bp->bio_error;
 169         g_destroy_bio(bp);
 170         /*
 171          * Do we have all sectors already?
 172          */
 173         pbp->bio_inbed++;
 174         if (pbp->bio_inbed < pbp->bio_children)
 175                 return;
 176         sc = pbp->bio_to->geom->softc;
 177         if (pbp->bio_error != 0) {
 178                 G_ELI_LOGREQ(0, pbp, "%s() failed", __func__);
 179                 pbp->bio_completed = 0;
 180                 if (pbp->bio_driver2 != NULL) {
 181                         free(pbp->bio_driver2, M_ELI);
 182                         pbp->bio_driver2 = NULL;
 183                 }
 184                 g_io_deliver(pbp, pbp->bio_error);
 185                 atomic_subtract_int(&sc->sc_inflight, 1);
 186                 return;
 187         }
 188         mtx_lock(&sc->sc_queue_mtx);
 189         bioq_insert_tail(&sc->sc_queue, pbp);
 190         mtx_unlock(&sc->sc_queue_mtx);
 191         wakeup(sc);
 192 }
 193
 194 /*
 195  * The function is called after we encrypt and write data.
 196  *
 197  * g_eli_start -> g_eli_crypto_run -> g_eli_crypto_write_done -> g_io_request -> G_ELI_WRITE_DONE -> g_io_deliver
 198  */
 199 void
 200 g_eli_write_done(struct bio *bp)
 201 {
 202         struct g_eli_softc *sc;
 203         struct bio *pbp;
 204
 205         G_ELI_LOGREQ(2, bp, "Request done.");
 206         pbp = bp->bio_parent;
 207         if (pbp->bio_error == 0) {
 208                 if (bp->bio_error != 0)
 209                         pbp->bio_error = bp->bio_error;
 210         }
 211         g_destroy_bio(bp);
 212         /*
 213          * Do we have all sectors already?
 214          */
 215         pbp->bio_inbed++;
 216         if (pbp->bio_inbed < pbp->bio_children)
 217                 return;
 218         free(pbp->bio_driver2, M_ELI);
 219         pbp->bio_driver2 = NULL;
 220         if (pbp->bio_error != 0) {
 221                 G_ELI_LOGREQ(0, pbp, "Crypto WRITE request failed (error=%d).",
 222                     pbp->bio_error);
 223                 pbp->bio_completed = 0;
 224         }
 225         /*
 226          * Write is finished, send it up.
 227          */
 228         pbp->bio_completed = pbp->bio_length;
 229         sc = pbp->bio_to->geom->softc;
 230         g_io_deliver(pbp, pbp->bio_error);
 231         atomic_subtract_int(&sc->sc_inflight, 1);
 232 }
 233
 234 /*
 235  * This function should never be called, but GEOM made as it set ->orphan()
 236  * method for every geom.
 237  */
 238 static void
 239 g_eli_orphan_spoil_assert(struct g_consumer *cp)
 240 {
 241
 242         panic("Function %s() called for %s.", __func__, cp->geom->name);
 243 }
 244
 245 static void
 246 g_eli_orphan(struct g_consumer *cp)
 247 {
 248         struct g_eli_softc *sc;
 249
 250         g_topology_assert();
 251         sc = cp->geom->softc;
 252         if (sc == NULL)
 253                 return;
 254         g_eli_destroy(sc, TRUE);
 255 }
 256
 257 /*
 258  * BIO_READ:
 259  *      G_ELI_START -> g_eli_crypto_read -> g_io_request -> g_eli_read_done -> g_eli_crypto_run -> g_eli_crypto_read_done -> g_io_deliver
 260  * BIO_WRITE:
 261  *      G_ELI_START -> g_eli_crypto_run -> g_eli_crypto_write_done -> g_io_request -> g_eli_write_done -> g_io_deliver
 262  */
 263 static void
 264 g_eli_start(struct bio *bp)
 265 {
 266         struct g_eli_softc *sc;
 267         struct g_consumer *cp;
 268         struct bio *cbp;
 269
 270         sc = bp->bio_to->geom->softc;
 271         KASSERT(sc != NULL,
 272             ("Provider's error should be set (error=%d)(device=%s).",
 273             bp->bio_to->error, bp->bio_to->name));
 274         G_ELI_LOGREQ(2, bp, "Request received.");
 275
 276         switch (bp->bio_cmd) {
 277         case BIO_READ:
 278         case BIO_WRITE:
 279         case BIO_GETATTR:
 280         case BIO_FLUSH:
 281                 break;
 282         case BIO_DELETE:
 283                 /*
 284                  * We could eventually support BIO_DELETE request.
 285                  * It could be done by overwritting requested sector with
 286                  * random data g_eli_overwrites number of times.
 287                  */
 288         default:
 289                 g_io_deliver(bp, EOPNOTSUPP);
 290                 return;
 291         }
 292         cbp = g_clone_bio(bp);
 293         if (cbp == NULL) {
 294                 g_io_deliver(bp, ENOMEM);
 295                 return;
 296         }
 297         bp->bio_driver1 = cbp;
 298         bp->bio_pflags = G_ELI_NEW_BIO;
 299         switch (bp->bio_cmd) {
 300         case BIO_READ:
 301                 if (!(sc->sc_flags & G_ELI_FLAG_AUTH)) {
 302                         g_eli_crypto_read(sc, bp, 0);
 303                         break;
 304                 }
 305                 /* FALLTHROUGH */
 306         case BIO_WRITE:
 307                 mtx_lock(&sc->sc_queue_mtx);
 308                 bioq_insert_tail(&sc->sc_queue, bp);
 309                 mtx_unlock(&sc->sc_queue_mtx);
 310                 wakeup(sc);
 311                 break;
 312         case BIO_GETATTR:
 313         case BIO_FLUSH:
 314                 cbp->bio_done = g_std_done;
 315                 cp = LIST_FIRST(&sc->sc_geom->consumer);
 316                 cbp->bio_to = cp->provider;
 317                 G_ELI_LOGREQ(2, cbp, "Sending request.");
 318                 g_io_request(cbp, cp);
 319                 break;
 320         }
 321 }
 322
 323 static int
 324 g_eli_newsession(struct g_eli_worker *wr)
 325 {
 326         struct g_eli_softc *sc;
 327         struct cryptoini crie, cria;
 328         int error;
 329
 330         sc = wr->w_softc;
 331
 332         bzero(&crie, sizeof(crie));
 333         crie.cri_alg = sc->sc_ealgo;
 334         crie.cri_klen = sc->sc_ekeylen;
 335         if (sc->sc_ealgo == CRYPTO_AES_XTS)
 336                 crie.cri_klen <<= 1;
 337         if ((sc->sc_flags & G_ELI_FLAG_FIRST_KEY) != 0) {
 338                 crie.cri_key = g_eli_key_hold(sc, 0,
 339                     LIST_FIRST(&sc->sc_geom->consumer)->provider->sectorsize);
 340         } else {
 341                 crie.cri_key = sc->sc_ekey;
 342         }
 343         if (sc->sc_flags & G_ELI_FLAG_AUTH) {
 344                 bzero(&cria, sizeof(cria));
 345                 cria.cri_alg = sc->sc_aalgo;
 346                 cria.cri_klen = sc->sc_akeylen;
 347                 cria.cri_key = sc->sc_akey;
 348                 crie.cri_next = &cria;
 349         }
 350
 351         switch (sc->sc_crypto) {
 352         case G_ELI_CRYPTO_SW:
 353                 error = crypto_newsession(&wr->w_sid, &crie,
 354                     CRYPTOCAP_F_SOFTWARE);
 355                 break;
 356         case G_ELI_CRYPTO_HW:
 357                 error = crypto_newsession(&wr->w_sid, &crie,
 358                     CRYPTOCAP_F_HARDWARE);
 359                 break;
 360         case G_ELI_CRYPTO_UNKNOWN:
 361                 error = crypto_newsession(&wr->w_sid, &crie,
 362                     CRYPTOCAP_F_HARDWARE);
 363                 if (error == 0) {
 364                         mtx_lock(&sc->sc_queue_mtx);
 365                         if (sc->sc_crypto == G_ELI_CRYPTO_UNKNOWN)
 366                                 sc->sc_crypto = G_ELI_CRYPTO_HW;
 367                         mtx_unlock(&sc->sc_queue_mtx);
 368                 } else {
 369                         error = crypto_newsession(&wr->w_sid, &crie,
 370                             CRYPTOCAP_F_SOFTWARE);
 371                         mtx_lock(&sc->sc_queue_mtx);
 372                         if (sc->sc_crypto == G_ELI_CRYPTO_UNKNOWN)
 373                                 sc->sc_crypto = G_ELI_CRYPTO_SW;
 374                         mtx_unlock(&sc->sc_queue_mtx);
 375                 }
 376                 break;
 377         default:
 378                 panic("%s: invalid condition", __func__);
 379         }
 380
 381         if ((sc->sc_flags & G_ELI_FLAG_FIRST_KEY) != 0)
 382                 g_eli_key_drop(sc, crie.cri_key);
 383
 384         return (error);
 385 }
 386
 387 static void
 388 g_eli_freesession(struct g_eli_worker *wr)
 389 {
 390
 391         crypto_freesession(wr->w_sid);
 392 }
 393
 394 static void
 395 g_eli_cancel(struct g_eli_softc *sc)
 396 {
 397         struct bio *bp;
 398
 399         mtx_assert(&sc->sc_queue_mtx, MA_OWNED);
 400
 401         while ((bp = bioq_takefirst(&sc->sc_queue)) != NULL) {
 402                 KASSERT(bp->bio_pflags == G_ELI_NEW_BIO,
 403                     ("Not new bio when canceling (bp=%p).", bp));
 404                 g_io_deliver(bp, ENXIO);
 405         }
 406 }
 407
 408 static struct bio *
 409 g_eli_takefirst(struct g_eli_softc *sc)
 410 {
 411         struct bio *bp;
 412
 413         mtx_assert(&sc->sc_queue_mtx, MA_OWNED);
 414
 415         if (!(sc->sc_flags & G_ELI_FLAG_SUSPEND))
 416                 return (bioq_takefirst(&sc->sc_queue));
 417         /*
 418          * Device suspended, so we skip new I/O requests.
 419          */
 420         TAILQ_FOREACH(bp, &sc->sc_queue.queue, bio_queue) {
 421                 if (bp->bio_pflags != G_ELI_NEW_BIO)
 422                         break;
 423         }
 424         if (bp != NULL)
 425                 bioq_remove(&sc->sc_queue, bp);
 426         return (bp);
 427 }
 428
 429 /*
 430  * This is the main function for kernel worker thread when we don't have
 431  * hardware acceleration and we have to do cryptography in software.
 432  * Dedicated thread is needed, so we don't slow down g_up/g_down GEOM
 433  * threads with crypto work.
 434  */
 435 static void
 436 g_eli_worker(void *arg)
 437 {
 438         struct g_eli_softc *sc;
 439         struct g_eli_worker *wr;
 440         struct bio *bp;
 441         int error;
 442
 443         wr = arg;
 444         sc = wr->w_softc;
 445 #ifdef SMP
 446         /* Before sched_bind() to a CPU, wait for all CPUs to go on-line. */
 447         if (sc->sc_cpubind) {
 448                 while (!smp_started)
 449                         tsleep(wr, 0, "geli:smp", hz / 4);
 450         }
 451 #endif
 452         thread_lock(curthread);
 453         sched_prio(curthread, PUSER);
 454         if (sc->sc_cpubind)
 455                 sched_bind(curthread, wr->w_number % mp_ncpus);
 456         thread_unlock(curthread);
 457
 458         G_ELI_DEBUG(1, "Thread %s started.", curthread->td_proc->p_comm);
 459
 460         for (;;) {
 461                 mtx_lock(&sc->sc_queue_mtx);
 462 again:
 463                 bp = g_eli_takefirst(sc);
 464                 if (bp == NULL) {
 465                         if (sc->sc_flags & G_ELI_FLAG_DESTROY) {
 466                                 g_eli_cancel(sc);
 467                                 LIST_REMOVE(wr, w_next);
 468                                 g_eli_freesession(wr);
 469                                 free(wr, M_ELI);
 470                                 G_ELI_DEBUG(1, "Thread %s exiting.",
 471                                     curthread->td_proc->p_comm);
 472                                 wakeup(&sc->sc_workers);
 473                                 mtx_unlock(&sc->sc_queue_mtx);
 474                                 kproc_exit(0);
 475                         }
 476                         while (sc->sc_flags & G_ELI_FLAG_SUSPEND) {
 477                                 if (sc->sc_inflight > 0) {
 478                                         G_ELI_DEBUG(0, "inflight=%d", sc->sc_inflight);
 479                                         /*
 480                                          * We still have inflight BIOs, so
 481                                          * sleep and retry.
 482                                          */
 483                                         msleep(sc, &sc->sc_queue_mtx, PRIBIO,
 484                                             "geli:inf", hz / 5);
 485                                         goto again;
 486                                 }
 487                                 /*
 488                                  * Suspend requested, mark the worker as
 489                                  * suspended and go to sleep.
 490                                  */
 491                                 if (wr->w_active) {
 492                                         g_eli_freesession(wr);
 493                                         wr->w_active = FALSE;
 494                                 }
 495                                 wakeup(&sc->sc_workers);
 496                                 msleep(sc, &sc->sc_queue_mtx, PRIBIO,
 497                                     "geli:suspend", 0);
 498                                 if (!wr->w_active &&
 499                                     !(sc->sc_flags & G_ELI_FLAG_SUSPEND)) {
 500                                         error = g_eli_newsession(wr);
 501                                         KASSERT(error == 0,
 502                                             ("g_eli_newsession() failed on resume (error=%d)",
 503                                             error));
 504                                         wr->w_active = TRUE;
 505                                 }
 506                                 goto again;
 507                         }
 508                         msleep(sc, &sc->sc_queue_mtx, PDROP, "geli:w", 0);
 509                         continue;
 510                 }
 511                 if (bp->bio_pflags == G_ELI_NEW_BIO)
 512                         atomic_add_int(&sc->sc_inflight, 1);
 513                 mtx_unlock(&sc->sc_queue_mtx);
 514                 if (bp->bio_pflags == G_ELI_NEW_BIO) {
 515                         bp->bio_pflags = 0;
 516                         if (sc->sc_flags & G_ELI_FLAG_AUTH) {
 517                                 if (bp->bio_cmd == BIO_READ)
 518                                         g_eli_auth_read(sc, bp);
 519                                 else
 520                                         g_eli_auth_run(wr, bp);
 521                         } else {
 522                                 if (bp->bio_cmd == BIO_READ)
 523                                         g_eli_crypto_read(sc, bp, 1);
 524                                 else
 525                                         g_eli_crypto_run(wr, bp);
 526                         }
 527                 } else {
 528                         if (sc->sc_flags & G_ELI_FLAG_AUTH)
 529                                 g_eli_auth_run(wr, bp);
 530                         else
 531                                 g_eli_crypto_run(wr, bp);
 532                 }
 533         }
 534 }
 535
 536 /*
 537  * Here we generate IV. It is unique for every sector.
 538  */
 539 void
 540 g_eli_crypto_ivgen(struct g_eli_softc *sc, off_t offset, u_char *iv,
 541     size_t size)
 542 {
 543         uint8_t off[8];
 544
 545         if ((sc->sc_flags & G_ELI_FLAG_NATIVE_BYTE_ORDER) != 0)
 546                 bcopy(&offset, off, sizeof(off));
 547         else
 548                 le64enc(off, (uint64_t)offset);
 549
 550         switch (sc->sc_ealgo) {
 551         case CRYPTO_AES_XTS:
 552                 bcopy(off, iv, sizeof(off));
 553                 bzero(iv + sizeof(off), size - sizeof(off));
 554                 break;
 555         default:
 556             {
 557                 u_char hash[SHA256_DIGEST_LENGTH];
 558                 SHA256_CTX ctx;
 559
 560                 /* Copy precalculated SHA256 context for IV-Key. */
 561                 bcopy(&sc->sc_ivctx, &ctx, sizeof(ctx));
 562                 SHA256_Update(&ctx, off, sizeof(off));
 563                 SHA256_Final(hash, &ctx);
 564                 bcopy(hash, iv, MIN(sizeof(hash), size));
 565                 break;
 566             }
 567         }
 568 }
 569
 570 int
 571 g_eli_read_metadata(struct g_class *mp, struct g_provider *pp,
 572     struct g_eli_metadata *md)
 573 {
 574         struct g_geom *gp;
 575         struct g_consumer *cp;
 576         u_char *buf = NULL;
 577         int error;
 578
 579         g_topology_assert();
 580
 581         gp = g_new_geomf(mp, "eli:taste");
 582         gp->start = g_eli_start;
 583         gp->access = g_std_access;
 584         /*
 585          * g_eli_read_metadata() is always called from the event thread.
 586          * Our geom is created and destroyed in the same event, so there
 587          * could be no orphan nor spoil event in the meantime.
 588          */
 589         gp->orphan = g_eli_orphan_spoil_assert;
 590         gp->spoiled = g_eli_orphan_spoil_assert;
 591         cp = g_new_consumer(gp);
 592         error = g_attach(cp, pp);
 593         if (error != 0)
 594                 goto end;
 595         error = g_access(cp, 1, 0, 0);
 596         if (error != 0)
 597                 goto end;
 598         g_topology_unlock();
 599         buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
 600             &error);
 601         g_topology_lock();
 602         if (buf == NULL)
 603                 goto end;
 604         eli_metadata_decode(buf, md);
 605 end:
 606         if (buf != NULL)
 607                 g_free(buf);
 608         if (cp->provider != NULL) {
 609                 if (cp->acr == 1)
 610                         g_access(cp, -1, 0, 0);
 611                 g_detach(cp);
 612         }
 613         g_destroy_consumer(cp);
 614         g_destroy_geom(gp);
 615         return (error);
 616 }
 617
 618 /*
 619  * The function is called when we had last close on provider and user requested
 620  * to close it when this situation occur.
 621  */
 622 static void
 623 g_eli_last_close(void *arg, int flags __unused)
 624 {
 625         struct g_geom *gp;
 626         char gpname[64];
 627         int error;
 628
 629         g_topology_assert();
 630         gp = arg;
 631         strlcpy(gpname, gp->name, sizeof(gpname));
 632         error = g_eli_destroy(gp->softc, TRUE);
 633         KASSERT(error == 0, ("Cannot detach %s on last close (error=%d).",
 634             gpname, error));
 635         G_ELI_DEBUG(0, "Detached %s on last close.", gpname);
 636 }
 637
 638 int
 639 g_eli_access(struct g_provider *pp, int dr, int dw, int de)
 640 {
 641         struct g_eli_softc *sc;
 642         struct g_geom *gp;
 643
 644         gp = pp->geom;
 645         sc = gp->softc;
 646
 647         if (dw > 0) {
 648                 if (sc->sc_flags & G_ELI_FLAG_RO) {
 649                         /* Deny write attempts. */
 650                         return (EROFS);
 651                 }
 652                 /* Someone is opening us for write, we need to remember that. */
 653                 sc->sc_flags |= G_ELI_FLAG_WOPEN;
 654                 return (0);
 655         }
 656         /* Is this the last close? */
 657         if (pp->acr + dr > 0 || pp->acw + dw > 0 || pp->ace + de > 0)
 658                 return (0);
 659
 660         /*
 661          * Automatically detach on last close if requested.
 662          */
 663         if ((sc->sc_flags & G_ELI_FLAG_RW_DETACH) ||
 664             (sc->sc_flags & G_ELI_FLAG_WOPEN)) {
 665                 g_post_event(g_eli_last_close, gp, M_WAITOK, NULL);
 666         }
 667         return (0);
 668 }
 669
 670 static int
 671 g_eli_cpu_is_disabled(int cpu)
 672 {
 673 #ifdef SMP
 674         return (CPU_ISSET(cpu, &hlt_cpus_mask));
 675 #else
 676         return (0);
 677 #endif
 678 }
 679
 680 struct g_geom *
 681 g_eli_create(struct gctl_req *req, struct g_class *mp, struct g_provider *bpp,
 682     const struct g_eli_metadata *md, const u_char *mkey, int nkey)
 683 {
 684         struct g_eli_softc *sc;
 685         struct g_eli_worker *wr;
 686         struct g_geom *gp;
 687         struct g_provider *pp;
 688         struct g_consumer *cp;
 689         u_int i, threads;
 690         int error;
 691
 692         G_ELI_DEBUG(1, "Creating device %s%s.", bpp->name, G_ELI_SUFFIX);
 693
 694         gp = g_new_geomf(mp, "%s%s", bpp->name, G_ELI_SUFFIX);
 695         sc = malloc(sizeof(*sc), M_ELI, M_WAITOK | M_ZERO);
 696         gp->start = g_eli_start;
 697         /*
 698          * Spoiling cannot happen actually, because we keep provider open for
 699          * writing all the time or provider is read-only.
 700          */
 701         gp->spoiled = g_eli_orphan_spoil_assert;
 702         gp->orphan = g_eli_orphan;
 703         gp->dumpconf = g_eli_dumpconf;
 704         /*
 705          * If detach-on-last-close feature is not enabled and we don't operate
 706          * on read-only provider, we can simply use g_std_access().
 707          */
 708         if (md->md_flags & (G_ELI_FLAG_WO_DETACH | G_ELI_FLAG_RO))
 709                 gp->access = g_eli_access;
 710         else
 711                 gp->access = g_std_access;
 712
 713         sc->sc_inflight = 0;
 714         sc->sc_crypto = G_ELI_CRYPTO_UNKNOWN;
 715         sc->sc_flags = md->md_flags;
 716         /* Backward compatibility. */
 717         if (md->md_version < 4)
 718                 sc->sc_flags |= G_ELI_FLAG_NATIVE_BYTE_ORDER;
 719         if (md->md_version < 5)
 720                 sc->sc_flags |= G_ELI_FLAG_SINGLE_KEY;
 721         if (md->md_version < 6 && (sc->sc_flags & G_ELI_FLAG_AUTH) != 0)
 722                 sc->sc_flags |= G_ELI_FLAG_FIRST_KEY;
 723         sc->sc_ealgo = md->md_ealgo;
 724         sc->sc_nkey = nkey;
 725
 726         if (sc->sc_flags & G_ELI_FLAG_AUTH) {
 727                 sc->sc_akeylen = sizeof(sc->sc_akey) * 8;
 728                 sc->sc_aalgo = md->md_aalgo;
 729                 sc->sc_alen = g_eli_hashlen(sc->sc_aalgo);
 730
 731                 sc->sc_data_per_sector = bpp->sectorsize - sc->sc_alen;
 732                 /*
 733                  * Some hash functions (like SHA1 and RIPEMD160) generates hash
 734                  * which length is not multiple of 128 bits, but we want data
 735                  * length to be multiple of 128, so we can encrypt without
 736                  * padding. The line below rounds down data length to multiple
 737                  * of 128 bits.
 738                  */
 739                 sc->sc_data_per_sector -= sc->sc_data_per_sector % 16;
 740
 741                 sc->sc_bytes_per_sector =
 742                     (md->md_sectorsize - 1) / sc->sc_data_per_sector + 1;
 743                 sc->sc_bytes_per_sector *= bpp->sectorsize;
 744         }
 745
 746         gp->softc = sc;
 747         sc->sc_geom = gp;
 748
 749         bioq_init(&sc->sc_queue);
 750         mtx_init(&sc->sc_queue_mtx, "geli:queue", NULL, MTX_DEF);
 751         mtx_init(&sc->sc_ekeys_lock, "geli:ekeys", NULL, MTX_DEF);
 752
 753         pp = NULL;
 754         cp = g_new_consumer(gp);
 755         error = g_attach(cp, bpp);
 756         if (error != 0) {
 757                 if (req != NULL) {
 758                         gctl_error(req, "Cannot attach to %s (error=%d).",
 759                             bpp->name, error);
 760                 } else {
 761                         G_ELI_DEBUG(1, "Cannot attach to %s (error=%d).",
 762                             bpp->name, error);
 763                 }
 764                 goto failed;
 765         }
 766         /*
 767          * Keep provider open all the time, so we can run critical tasks,
 768          * like Master Keys deletion, without wondering if we can open
 769          * provider or not.
 770          * We don't open provider for writing only when user requested read-only
 771          * access.
 772          */
 773         if (sc->sc_flags & G_ELI_FLAG_RO)
 774                 error = g_access(cp, 1, 0, 1);
 775         else
 776                 error = g_access(cp, 1, 1, 1);
 777         if (error != 0) {
 778                 if (req != NULL) {
 779                         gctl_error(req, "Cannot access %s (error=%d).",
 780                             bpp->name, error);
 781                 } else {
 782                         G_ELI_DEBUG(1, "Cannot access %s (error=%d).",
 783                             bpp->name, error);
 784                 }
 785                 goto failed;
 786         }
 787
 788         sc->sc_sectorsize = md->md_sectorsize;
 789         sc->sc_mediasize = bpp->mediasize;
 790         if (!(sc->sc_flags & G_ELI_FLAG_ONETIME))
 791                 sc->sc_mediasize -= bpp->sectorsize;
 792         if (!(sc->sc_flags & G_ELI_FLAG_AUTH))
 793                 sc->sc_mediasize -= (sc->sc_mediasize % sc->sc_sectorsize);
 794         else {
 795                 sc->sc_mediasize /= sc->sc_bytes_per_sector;
 796                 sc->sc_mediasize *= sc->sc_sectorsize;
 797         }
 798
 799         /*
 800          * Remember the keys in our softc structure.
 801          */
 802         g_eli_mkey_propagate(sc, mkey);
 803         sc->sc_ekeylen = md->md_keylen;
 804
 805         LIST_INIT(&sc->sc_workers);
 806
 807         threads = g_eli_threads;
 808         if (threads == 0)
 809                 threads = mp_ncpus;
 810         sc->sc_cpubind = (mp_ncpus > 1 && threads == mp_ncpus);
 811         for (i = 0; i < threads; i++) {
 812                 if (g_eli_cpu_is_disabled(i)) {
 813                         G_ELI_DEBUG(1, "%s: CPU %u disabled, skipping.",
 814                             bpp->name, i);
 815                         continue;
 816                 }
 817                 wr = malloc(sizeof(*wr), M_ELI, M_WAITOK | M_ZERO);
 818                 wr->w_softc = sc;
 819                 wr->w_number = i;
 820                 wr->w_active = TRUE;
 821
 822                 error = g_eli_newsession(wr);
 823                 if (error != 0) {
 824                         free(wr, M_ELI);
 825                         if (req != NULL) {
 826                                 gctl_error(req, "Cannot set up crypto session "
 827                                     "for %s (error=%d).", bpp->name, error);
 828                         } else {
 829                                 G_ELI_DEBUG(1, "Cannot set up crypto session "
 830                                     "for %s (error=%d).", bpp->name, error);
 831                         }
 832                         goto failed;
 833                 }
 834
 835                 error = kproc_create(g_eli_worker, wr, &wr->w_proc, 0, 0,
 836                     "g_eli[%u] %s", i, bpp->name);
 837                 if (error != 0) {
 838                         g_eli_freesession(wr);
 839                         free(wr, M_ELI);
 840                         if (req != NULL) {
 841                                 gctl_error(req, "Cannot create kernel thread "
 842                                     "for %s (error=%d).", bpp->name, error);
 843                         } else {
 844                                 G_ELI_DEBUG(1, "Cannot create kernel thread "
 845                                     "for %s (error=%d).", bpp->name, error);
 846                         }
 847                         goto failed;
 848                 }
 849                 LIST_INSERT_HEAD(&sc->sc_workers, wr, w_next);
 850         }
 851
 852         /*
 853          * Create decrypted provider.
 854          */
 855         pp = g_new_providerf(gp, "%s%s", bpp->name, G_ELI_SUFFIX);
 856         pp->mediasize = sc->sc_mediasize;
 857         pp->sectorsize = sc->sc_sectorsize;
 858
 859         g_error_provider(pp, 0);
 860
 861         G_ELI_DEBUG(0, "Device %s created.", pp->name);
 862         G_ELI_DEBUG(0, "Encryption: %s %u", g_eli_algo2str(sc->sc_ealgo),
 863             sc->sc_ekeylen);
 864         if (sc->sc_flags & G_ELI_FLAG_AUTH)
 865                 G_ELI_DEBUG(0, " Integrity: %s", g_eli_algo2str(sc->sc_aalgo));
 866         G_ELI_DEBUG(0, "    Crypto: %s",
 867             sc->sc_crypto == G_ELI_CRYPTO_SW ? "software" : "hardware");
 868         return (gp);
 869 failed:
 870         mtx_lock(&sc->sc_queue_mtx);
 871         sc->sc_flags |= G_ELI_FLAG_DESTROY;
 872         wakeup(sc);
 873         /*
 874          * Wait for kernel threads self destruction.
 875          */
 876         while (!LIST_EMPTY(&sc->sc_workers)) {
 877                 msleep(&sc->sc_workers, &sc->sc_queue_mtx, PRIBIO,
 878                     "geli:destroy", 0);
 879         }
 880         mtx_destroy(&sc->sc_queue_mtx);
 881         if (cp->provider != NULL) {
 882                 if (cp->acr == 1)
 883                         g_access(cp, -1, -1, -1);
 884                 g_detach(cp);
 885         }
 886         g_destroy_consumer(cp);
 887         g_destroy_geom(gp);
 888         g_eli_key_destroy(sc);
 889         bzero(sc, sizeof(*sc));
 890         free(sc, M_ELI);
 891         return (NULL);
 892 }
 893
 894 int
 895 g_eli_destroy(struct g_eli_softc *sc, boolean_t force)
 896 {
 897         struct g_geom *gp;
 898         struct g_provider *pp;
 899
 900         g_topology_assert();
 901
 902         if (sc == NULL)
 903                 return (ENXIO);
 904
 905         gp = sc->sc_geom;
 906         pp = LIST_FIRST(&gp->provider);
 907         if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) {
 908                 if (force) {
 909                         G_ELI_DEBUG(1, "Device %s is still open, so it "
 910                             "cannot be definitely removed.", pp->name);
 911                         sc->sc_flags |= G_ELI_FLAG_RW_DETACH;
 912                         gp->access = g_eli_access;
 913                         g_wither_provider(pp, ENXIO);
 914                         return (EBUSY);
 915                 } else {
 916                         G_ELI_DEBUG(1,
 917                             "Device %s is still open (r%dw%de%d).", pp->name,
 918                             pp->acr, pp->acw, pp->ace);
 919                         return (EBUSY);
 920                 }
 921         }
 922
 923         mtx_lock(&sc->sc_queue_mtx);
 924         sc->sc_flags |= G_ELI_FLAG_DESTROY;
 925         wakeup(sc);
 926         while (!LIST_EMPTY(&sc->sc_workers)) {
 927                 msleep(&sc->sc_workers, &sc->sc_queue_mtx, PRIBIO,
 928                     "geli:destroy", 0);
 929         }
 930         mtx_destroy(&sc->sc_queue_mtx);
 931         gp->softc = NULL;
 932         g_eli_key_destroy(sc);
 933         bzero(sc, sizeof(*sc));
 934         free(sc, M_ELI);
 935
 936         if (pp == NULL || (pp->acr == 0 && pp->acw == 0 && pp->ace == 0))
 937                 G_ELI_DEBUG(0, "Device %s destroyed.", gp->name);
 938         g_wither_geom_close(gp, ENXIO);
 939
 940         return (0);
 941 }
 942
 943 static int
 944 g_eli_destroy_geom(struct gctl_req *req __unused,
 945     struct g_class *mp __unused, struct g_geom *gp)
 946 {
 947         struct g_eli_softc *sc;
 948
 949         sc = gp->softc;
 950         return (g_eli_destroy(sc, FALSE));
 951 }
 952
 953 static int
 954 g_eli_keyfiles_load(struct hmac_ctx *ctx, const char *provider)
 955 {
 956         u_char *keyfile, *data;
 957         char *file, name[64];
 958         size_t size;
 959         int i;
 960
 961         for (i = 0; ; i++) {
 962                 snprintf(name, sizeof(name), "%s:geli_keyfile%d", provider, i);
 963                 keyfile = preload_search_by_type(name);
 964                 if (keyfile == NULL)
 965                         return (i);     /* Return number of loaded keyfiles. */
 966                 data = preload_fetch_addr(keyfile);
 967                 if (data == NULL) {
 968                         G_ELI_DEBUG(0, "Cannot find key file data for %s.",
 969                             name);
 970                         return (0);
 971                 }
 972                 size = preload_fetch_size(keyfile);
 973                 if (size == 0) {
 974                         G_ELI_DEBUG(0, "Cannot find key file size for %s.",
 975                             name);
 976                         return (0);
 977                 }
 978                 file = preload_search_info(keyfile, MODINFO_NAME);
 979                 if (file == NULL) {
 980                         G_ELI_DEBUG(0, "Cannot find key file name for %s.",
 981                             name);
 982                         return (0);
 983                 }
 984                 G_ELI_DEBUG(1, "Loaded keyfile %s for %s (type: %s).", file,
 985                     provider, name);
 986                 g_eli_crypto_hmac_update(ctx, data, size);
 987         }
 988 }
 989
 990 static void
 991 g_eli_keyfiles_clear(const char *provider)
 992 {
 993         u_char *keyfile, *data;
 994         char name[64];
 995         size_t size;
 996         int i;
 997
 998         for (i = 0; ; i++) {
 999                 snprintf(name, sizeof(name), "%s:geli_keyfile%d", provider, i);
1000                 keyfile = preload_search_by_type(name);
1001                 if (keyfile == NULL)
1002                         return;
1003                 data = preload_fetch_addr(keyfile);
1004                 size = preload_fetch_size(keyfile);
1005                 if (data != NULL && size != 0)
1006                         bzero(data, size);
1007         }
1008 }
1009
1010 /*
1011  * Tasting is only made on boot.
1012  * We detect providers which should be attached before root is mounted.
1013  */
1014 static struct g_geom *
1015 g_eli_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
1016 {
1017         struct g_eli_metadata md;
1018         struct g_geom *gp;
1019         struct hmac_ctx ctx;
1020         char passphrase[256];
1021         u_char key[G_ELI_USERKEYLEN], mkey[G_ELI_DATAIVKEYLEN];
1022         u_int i, nkey, nkeyfiles, tries;
1023         int error;
1024
1025         g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
1026         g_topology_assert();
1027
1028         if (root_mounted() || g_eli_tries == 0)
1029                 return (NULL);
1030
1031         G_ELI_DEBUG(3, "Tasting %s.", pp->name);
1032
1033         error = g_eli_read_metadata(mp, pp, &md);
1034         if (error != 0)
1035                 return (NULL);
1036         gp = NULL;
1037
1038         if (strcmp(md.md_magic, G_ELI_MAGIC) != 0)
1039                 return (NULL);
1040         if (md.md_version > G_ELI_VERSION) {
1041                 printf("geom_eli.ko module is too old to handle %s.\n",
1042                     pp->name);
1043                 return (NULL);
1044         }
1045         if (md.md_provsize != pp->mediasize)
1046                 return (NULL);
1047         /* Should we attach it on boot? */
1048         if (!(md.md_flags & G_ELI_FLAG_BOOT))
1049                 return (NULL);
1050         if (md.md_keys == 0x00) {
1051                 G_ELI_DEBUG(0, "No valid keys on %s.", pp->name);
1052                 return (NULL);
1053         }
1054         if (md.md_iterations == -1) {
1055                 /* If there is no passphrase, we try only once. */
1056                 tries = 1;
1057         } else {
1058                 /* Ask for the passphrase no more than g_eli_tries times. */
1059                 tries = g_eli_tries;
1060         }
1061
1062         for (i = 0; i < tries; i++) {
1063                 g_eli_crypto_hmac_init(&ctx, NULL, 0);
1064
1065                 /*
1066                  * Load all key files.
1067                  */
1068                 nkeyfiles = g_eli_keyfiles_load(&ctx, pp->name);
1069
1070                 if (nkeyfiles == 0 && md.md_iterations == -1) {
1071                         /*
1072                          * No key files and no passphrase, something is
1073                          * definitely wrong here.
1074                          * geli(8) doesn't allow for such situation, so assume
1075                          * that there was really no passphrase and in that case
1076                          * key files are no properly defined in loader.conf.
1077                          */
1078                         G_ELI_DEBUG(0,
1079                             "Found no key files in loader.conf for %s.",
1080                             pp->name);
1081                         return (NULL);
1082                 }
1083
1084                 /* Ask for the passphrase if defined. */
1085                 if (md.md_iterations >= 0) {
1086                         printf("Enter passphrase for %s: ", pp->name);
1087                         cngets(passphrase, sizeof(passphrase),
1088                             g_eli_visible_passphrase);
1089                 }
1090
1091                 /*
1092                  * Prepare Derived-Key from the user passphrase.
1093                  */
1094                 if (md.md_iterations == 0) {
1095                         g_eli_crypto_hmac_update(&ctx, md.md_salt,
1096                             sizeof(md.md_salt));
1097                         g_eli_crypto_hmac_update(&ctx, passphrase,
1098                             strlen(passphrase));
1099                         bzero(passphrase, sizeof(passphrase));
1100                 } else if (md.md_iterations > 0) {
1101                         u_char dkey[G_ELI_USERKEYLEN];
1102
1103                         pkcs5v2_genkey(dkey, sizeof(dkey), md.md_salt,
1104                             sizeof(md.md_salt), passphrase, md.md_iterations);
1105                         bzero(passphrase, sizeof(passphrase));
1106                         g_eli_crypto_hmac_update(&ctx, dkey, sizeof(dkey));
1107                         bzero(dkey, sizeof(dkey));
1108                 }
1109
1110                 g_eli_crypto_hmac_final(&ctx, key, 0);
1111
1112                 /*
1113                  * Decrypt Master-Key.
1114                  */
1115                 error = g_eli_mkey_decrypt(&md, key, mkey, &nkey);
1116                 bzero(key, sizeof(key));
1117                 if (error == -1) {
1118                         if (i == tries - 1) {
1119                                 G_ELI_DEBUG(0,
1120                                     "Wrong key for %s. No tries left.",
1121                                     pp->name);
1122                                 g_eli_keyfiles_clear(pp->name);
1123                                 return (NULL);
1124                         }
1125                         G_ELI_DEBUG(0, "Wrong key for %s. Tries left: %u.",
1126                             pp->name, tries - i - 1);
1127                         /* Try again. */
1128                         continue;
1129                 } else if (error > 0) {
1130                         G_ELI_DEBUG(0, "Cannot decrypt Master Key for %s (error=%d).",
1131                             pp->name, error);
1132                         g_eli_keyfiles_clear(pp->name);
1133                         return (NULL);
1134                 }
1135                 g_eli_keyfiles_clear(pp->name);
1136                 G_ELI_DEBUG(1, "Using Master Key %u for %s.", nkey, pp->name);
1137                 break;
1138         }
1139
1140         /*
1141          * We have correct key, let's attach provider.
1142          */
1143         gp = g_eli_create(NULL, mp, pp, &md, mkey, nkey);
1144         bzero(mkey, sizeof(mkey));
1145         bzero(&md, sizeof(md));
1146         if (gp == NULL) {
1147                 G_ELI_DEBUG(0, "Cannot create device %s%s.", pp->name,
1148                     G_ELI_SUFFIX);
1149                 return (NULL);
1150         }
1151         return (gp);
1152 }
1153
1154 static void
1155 g_eli_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
1156     struct g_consumer *cp, struct g_provider *pp)
1157 {
1158         struct g_eli_softc *sc;
1159
1160         g_topology_assert();
1161         sc = gp->softc;
1162         if (sc == NULL)
1163                 return;
1164         if (pp != NULL || cp != NULL)
1165                 return; /* Nothing here. */
1166
1167         sbuf_printf(sb, "%s<KeysTotal>%ju</KeysTotal>\n", indent,
1168             (uintmax_t)sc->sc_ekeys_total);
1169         sbuf_printf(sb, "%s<KeysAllocated>%ju</KeysAllocated>\n", indent,
1170             (uintmax_t)sc->sc_ekeys_allocated);
1171         sbuf_printf(sb, "%s<Flags>", indent);
1172         if (sc->sc_flags == 0)
1173                 sbuf_printf(sb, "NONE");
1174         else {
1175                 int first = 1;
1176
1177 #define ADD_FLAG(flag, name)    do {                                    \
1178         if (sc->sc_flags & (flag)) {                                    \
1179                 if (!first)                                             \
1180                         sbuf_printf(sb, ", ");                          \
1181                 else                                                    \
1182                         first = 0;                                      \
1183                 sbuf_printf(sb, name);                                  \
1184         }                                                               \
1185 } while (0)
1186                 ADD_FLAG(G_ELI_FLAG_SUSPEND, "SUSPEND");
1187                 ADD_FLAG(G_ELI_FLAG_SINGLE_KEY, "SINGLE-KEY");
1188                 ADD_FLAG(G_ELI_FLAG_NATIVE_BYTE_ORDER, "NATIVE-BYTE-ORDER");
1189                 ADD_FLAG(G_ELI_FLAG_ONETIME, "ONETIME");
1190                 ADD_FLAG(G_ELI_FLAG_BOOT, "BOOT");
1191                 ADD_FLAG(G_ELI_FLAG_WO_DETACH, "W-DETACH");
1192                 ADD_FLAG(G_ELI_FLAG_RW_DETACH, "RW-DETACH");
1193                 ADD_FLAG(G_ELI_FLAG_AUTH, "AUTH");
1194                 ADD_FLAG(G_ELI_FLAG_WOPEN, "W-OPEN");
1195                 ADD_FLAG(G_ELI_FLAG_DESTROY, "DESTROY");
1196                 ADD_FLAG(G_ELI_FLAG_RO, "READ-ONLY");
1197 #undef  ADD_FLAG
1198         }
1199         sbuf_printf(sb, "</Flags>\n");
1200
1201         if (!(sc->sc_flags & G_ELI_FLAG_ONETIME)) {
1202                 sbuf_printf(sb, "%s<UsedKey>%u</UsedKey>\n", indent,
1203                     sc->sc_nkey);
1204         }
1205         sbuf_printf(sb, "%s<Crypto>", indent);
1206         switch (sc->sc_crypto) {
1207         case G_ELI_CRYPTO_HW:
1208                 sbuf_printf(sb, "hardware");
1209                 break;
1210         case G_ELI_CRYPTO_SW:
1211                 sbuf_printf(sb, "software");
1212                 break;
1213         default:
1214                 sbuf_printf(sb, "UNKNOWN");
1215                 break;
1216         }
1217         sbuf_printf(sb, "</Crypto>\n");
1218         if (sc->sc_flags & G_ELI_FLAG_AUTH) {
1219                 sbuf_printf(sb,
1220                     "%s<AuthenticationAlgorithm>%s</AuthenticationAlgorithm>\n",
1221                     indent, g_eli_algo2str(sc->sc_aalgo));
1222         }
1223         sbuf_printf(sb, "%s<KeyLength>%u</KeyLength>\n", indent,
1224             sc->sc_ekeylen);
1225         sbuf_printf(sb, "%s<EncryptionAlgorithm>%s</EncryptionAlgorithm>\n", indent,
1226             g_eli_algo2str(sc->sc_ealgo));
1227         sbuf_printf(sb, "%s<State>%s</State>\n", indent,
1228             (sc->sc_flags & G_ELI_FLAG_SUSPEND) ? "SUSPENDED" : "ACTIVE");
1229 }
1230
1231 static void
1232 g_eli_shutdown_pre_sync(void *arg, int howto)
1233 {
1234         struct g_class *mp;
1235         struct g_geom *gp, *gp2;
1236         struct g_provider *pp;
1237         struct g_eli_softc *sc;
1238         int error;
1239
1240         mp = arg;
1241         DROP_GIANT();
1242         g_topology_lock();
1243         LIST_FOREACH_SAFE(gp, &mp->geom, geom, gp2) {
1244                 sc = gp->softc;
1245                 if (sc == NULL)
1246                         continue;
1247                 pp = LIST_FIRST(&gp->provider);
1248                 KASSERT(pp != NULL, ("No provider? gp=%p (%s)", gp, gp->name));
1249                 if (pp->acr + pp->acw + pp->ace == 0)
1250                         error = g_eli_destroy(sc, TRUE);
1251                 else {
1252                         sc->sc_flags |= G_ELI_FLAG_RW_DETACH;
1253                         gp->access = g_eli_access;
1254                 }
1255         }
1256         g_topology_unlock();
1257         PICKUP_GIANT();
1258 }
1259
1260 static void
1261 g_eli_init(struct g_class *mp)
1262 {
1263
1264         g_eli_pre_sync = EVENTHANDLER_REGISTER(shutdown_pre_sync,
1265             g_eli_shutdown_pre_sync, mp, SHUTDOWN_PRI_FIRST);
1266         if (g_eli_pre_sync == NULL)
1267                 G_ELI_DEBUG(0, "Warning! Cannot register shutdown event.");
1268 }
1269
1270 static void
1271 g_eli_fini(struct g_class *mp)
1272 {
1273
1274         if (g_eli_pre_sync != NULL)
1275                 EVENTHANDLER_DEREGISTER(shutdown_pre_sync, g_eli_pre_sync);
1276 }
1277
1278 DECLARE_GEOM_CLASS(g_eli_class, g_eli);
1279 MODULE_DEPEND(g_eli, crypto, 1, 1, 1);