xref: /freebsd/sys/geom/eli/g_eli.c (revision b1f92fa22938fe29ab7e53692ffe0ed7a0ecc4d0)
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 SYSCTL_INT(_kern_geom_eli, OID_AUTO, debug, CTLFLAG_RWTUN, &g_eli_debug, 0,
67     "Debug level");
68 static u_int g_eli_tries = 3;
69 SYSCTL_UINT(_kern_geom_eli, OID_AUTO, tries, CTLFLAG_RWTUN, &g_eli_tries, 0,
70     "Number of tries for entering the passphrase");
71 static u_int g_eli_visible_passphrase = GETS_NOECHO;
72 SYSCTL_UINT(_kern_geom_eli, OID_AUTO, visible_passphrase, CTLFLAG_RWTUN,
73     &g_eli_visible_passphrase, 0,
74     "Visibility of passphrase prompt (0 = invisible, 1 = visible, 2 = asterisk)");
75 u_int g_eli_overwrites = G_ELI_OVERWRITES;
76 SYSCTL_UINT(_kern_geom_eli, OID_AUTO, overwrites, CTLFLAG_RWTUN, &g_eli_overwrites,
77     0, "Number of times on-disk keys should be overwritten when destroying them");
78 static u_int g_eli_threads = 0;
79 SYSCTL_UINT(_kern_geom_eli, OID_AUTO, threads, CTLFLAG_RWTUN, &g_eli_threads, 0,
80     "Number of threads doing crypto work");
81 u_int g_eli_batch = 0;
82 SYSCTL_UINT(_kern_geom_eli, OID_AUTO, batch, CTLFLAG_RWTUN, &g_eli_batch, 0,
83     "Use crypto operations batching");
84 
85 /*
86  * Passphrase cached during boot, in order to be more user-friendly if
87  * there are multiple providers using the same passphrase.
88  */
89 static char cached_passphrase[256];
90 static u_int g_eli_boot_passcache = 1;
91 TUNABLE_INT("kern.geom.eli.boot_passcache", &g_eli_boot_passcache);
92 SYSCTL_UINT(_kern_geom_eli, OID_AUTO, boot_passcache, CTLFLAG_RD,
93     &g_eli_boot_passcache, 0,
94     "Passphrases are cached during boot process for possible reuse");
95 static void
96 fetch_loader_passphrase(void * dummy)
97 {
98 	char * env_passphrase;
99 
100 	KASSERT(dynamic_kenv, ("need dynamic kenv"));
101 
102 	if ((env_passphrase = kern_getenv("kern.geom.eli.passphrase")) != NULL) {
103 		/* Extract passphrase from the environment. */
104 		strlcpy(cached_passphrase, env_passphrase,
105 		    sizeof(cached_passphrase));
106 		freeenv(env_passphrase);
107 
108 		/* Wipe the passphrase from the environment. */
109 		kern_unsetenv("kern.geom.eli.passphrase");
110 	}
111 }
112 SYSINIT(geli_fetch_loader_passphrase, SI_SUB_KMEM + 1, SI_ORDER_ANY,
113     fetch_loader_passphrase, NULL);
114 static void
115 zero_boot_passcache(void * dummy)
116 {
117 
118 	memset(cached_passphrase, 0, sizeof(cached_passphrase));
119 }
120 EVENTHANDLER_DEFINE(mountroot, zero_boot_passcache, NULL, 0);
121 
122 static eventhandler_tag g_eli_pre_sync = NULL;
123 
124 static int g_eli_destroy_geom(struct gctl_req *req, struct g_class *mp,
125     struct g_geom *gp);
126 static void g_eli_init(struct g_class *mp);
127 static void g_eli_fini(struct g_class *mp);
128 
129 static g_taste_t g_eli_taste;
130 static g_dumpconf_t g_eli_dumpconf;
131 
132 struct g_class g_eli_class = {
133 	.name = G_ELI_CLASS_NAME,
134 	.version = G_VERSION,
135 	.ctlreq = g_eli_config,
136 	.taste = g_eli_taste,
137 	.destroy_geom = g_eli_destroy_geom,
138 	.init = g_eli_init,
139 	.fini = g_eli_fini
140 };
141 
142 
143 /*
144  * Code paths:
145  * BIO_READ:
146  *	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
147  * BIO_WRITE:
148  *	g_eli_start -> g_eli_crypto_run -> g_eli_crypto_write_done -> g_io_request -> g_eli_write_done -> g_io_deliver
149  */
150 
151 
152 /*
153  * EAGAIN from crypto(9) means, that we were probably balanced to another crypto
154  * accelerator or something like this.
155  * The function updates the SID and rerun the operation.
156  */
157 int
158 g_eli_crypto_rerun(struct cryptop *crp)
159 {
160 	struct g_eli_softc *sc;
161 	struct g_eli_worker *wr;
162 	struct bio *bp;
163 	int error;
164 
165 	bp = (struct bio *)crp->crp_opaque;
166 	sc = bp->bio_to->geom->softc;
167 	LIST_FOREACH(wr, &sc->sc_workers, w_next) {
168 		if (wr->w_number == bp->bio_pflags)
169 			break;
170 	}
171 	KASSERT(wr != NULL, ("Invalid worker (%u).", bp->bio_pflags));
172 	G_ELI_DEBUG(1, "Rerunning crypto %s request (sid: %ju -> %ju).",
173 	    bp->bio_cmd == BIO_READ ? "READ" : "WRITE", (uintmax_t)wr->w_sid,
174 	    (uintmax_t)crp->crp_sid);
175 	wr->w_sid = crp->crp_sid;
176 	crp->crp_etype = 0;
177 	error = crypto_dispatch(crp);
178 	if (error == 0)
179 		return (0);
180 	G_ELI_DEBUG(1, "%s: crypto_dispatch() returned %d.", __func__, error);
181 	crp->crp_etype = error;
182 	return (error);
183 }
184 
185 /*
186  * The function is called afer reading encrypted data from the provider.
187  *
188  * 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
189  */
190 void
191 g_eli_read_done(struct bio *bp)
192 {
193 	struct g_eli_softc *sc;
194 	struct bio *pbp;
195 
196 	G_ELI_LOGREQ(2, bp, "Request done.");
197 	pbp = bp->bio_parent;
198 	if (pbp->bio_error == 0 && bp->bio_error != 0)
199 		pbp->bio_error = bp->bio_error;
200 	g_destroy_bio(bp);
201 	/*
202 	 * Do we have all sectors already?
203 	 */
204 	pbp->bio_inbed++;
205 	if (pbp->bio_inbed < pbp->bio_children)
206 		return;
207 	sc = pbp->bio_to->geom->softc;
208 	if (pbp->bio_error != 0) {
209 		G_ELI_LOGREQ(0, pbp, "%s() failed (error=%d)", __func__,
210 		    pbp->bio_error);
211 		pbp->bio_completed = 0;
212 		if (pbp->bio_driver2 != NULL) {
213 			free(pbp->bio_driver2, M_ELI);
214 			pbp->bio_driver2 = NULL;
215 		}
216 		g_io_deliver(pbp, pbp->bio_error);
217 		atomic_subtract_int(&sc->sc_inflight, 1);
218 		return;
219 	}
220 	mtx_lock(&sc->sc_queue_mtx);
221 	bioq_insert_tail(&sc->sc_queue, pbp);
222 	mtx_unlock(&sc->sc_queue_mtx);
223 	wakeup(sc);
224 }
225 
226 /*
227  * The function is called after we encrypt and write data.
228  *
229  * g_eli_start -> g_eli_crypto_run -> g_eli_crypto_write_done -> g_io_request -> G_ELI_WRITE_DONE -> g_io_deliver
230  */
231 void
232 g_eli_write_done(struct bio *bp)
233 {
234 	struct g_eli_softc *sc;
235 	struct bio *pbp;
236 
237 	G_ELI_LOGREQ(2, bp, "Request done.");
238 	pbp = bp->bio_parent;
239 	if (pbp->bio_error == 0 && bp->bio_error != 0)
240 		pbp->bio_error = bp->bio_error;
241 	g_destroy_bio(bp);
242 	/*
243 	 * Do we have all sectors already?
244 	 */
245 	pbp->bio_inbed++;
246 	if (pbp->bio_inbed < pbp->bio_children)
247 		return;
248 	free(pbp->bio_driver2, M_ELI);
249 	pbp->bio_driver2 = NULL;
250 	if (pbp->bio_error != 0) {
251 		G_ELI_LOGREQ(0, pbp, "%s() failed (error=%d)", __func__,
252 		    pbp->bio_error);
253 		pbp->bio_completed = 0;
254 	} else
255 		pbp->bio_completed = pbp->bio_length;
256 
257 	/*
258 	 * Write is finished, send it up.
259 	 */
260 	sc = pbp->bio_to->geom->softc;
261 	g_io_deliver(pbp, pbp->bio_error);
262 	atomic_subtract_int(&sc->sc_inflight, 1);
263 }
264 
265 /*
266  * This function should never be called, but GEOM made as it set ->orphan()
267  * method for every geom.
268  */
269 static void
270 g_eli_orphan_spoil_assert(struct g_consumer *cp)
271 {
272 
273 	panic("Function %s() called for %s.", __func__, cp->geom->name);
274 }
275 
276 static void
277 g_eli_orphan(struct g_consumer *cp)
278 {
279 	struct g_eli_softc *sc;
280 
281 	g_topology_assert();
282 	sc = cp->geom->softc;
283 	if (sc == NULL)
284 		return;
285 	g_eli_destroy(sc, TRUE);
286 }
287 
288 /*
289  * BIO_READ:
290  *	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
291  * BIO_WRITE:
292  *	G_ELI_START -> g_eli_crypto_run -> g_eli_crypto_write_done -> g_io_request -> g_eli_write_done -> g_io_deliver
293  */
294 static void
295 g_eli_start(struct bio *bp)
296 {
297 	struct g_eli_softc *sc;
298 	struct g_consumer *cp;
299 	struct bio *cbp;
300 
301 	sc = bp->bio_to->geom->softc;
302 	KASSERT(sc != NULL,
303 	    ("Provider's error should be set (error=%d)(device=%s).",
304 	    bp->bio_to->error, bp->bio_to->name));
305 	G_ELI_LOGREQ(2, bp, "Request received.");
306 
307 	switch (bp->bio_cmd) {
308 	case BIO_READ:
309 	case BIO_WRITE:
310 	case BIO_GETATTR:
311 	case BIO_FLUSH:
312 		break;
313 	case BIO_DELETE:
314 		/*
315 		 * If the user hasn't set the NODELETE flag, we just pass
316 		 * it down the stack and let the layers beneath us do (or
317 		 * not) whatever they do with it.  If they have, we
318 		 * reject it.  A possible extension would be an
319 		 * additional flag to take it as a hint to shred the data
320 		 * with [multiple?] overwrites.
321 		 */
322 		if (!(sc->sc_flags & G_ELI_FLAG_NODELETE))
323 			break;
324 	default:
325 		g_io_deliver(bp, EOPNOTSUPP);
326 		return;
327 	}
328 	cbp = g_clone_bio(bp);
329 	if (cbp == NULL) {
330 		g_io_deliver(bp, ENOMEM);
331 		return;
332 	}
333 	bp->bio_driver1 = cbp;
334 	bp->bio_pflags = G_ELI_NEW_BIO;
335 	switch (bp->bio_cmd) {
336 	case BIO_READ:
337 		if (!(sc->sc_flags & G_ELI_FLAG_AUTH)) {
338 			g_eli_crypto_read(sc, bp, 0);
339 			break;
340 		}
341 		/* FALLTHROUGH */
342 	case BIO_WRITE:
343 		mtx_lock(&sc->sc_queue_mtx);
344 		bioq_insert_tail(&sc->sc_queue, bp);
345 		mtx_unlock(&sc->sc_queue_mtx);
346 		wakeup(sc);
347 		break;
348 	case BIO_GETATTR:
349 	case BIO_FLUSH:
350 	case BIO_DELETE:
351 		cbp->bio_done = g_std_done;
352 		cp = LIST_FIRST(&sc->sc_geom->consumer);
353 		cbp->bio_to = cp->provider;
354 		G_ELI_LOGREQ(2, cbp, "Sending request.");
355 		g_io_request(cbp, cp);
356 		break;
357 	}
358 }
359 
360 static int
361 g_eli_newsession(struct g_eli_worker *wr)
362 {
363 	struct g_eli_softc *sc;
364 	struct cryptoini crie, cria;
365 	int error;
366 
367 	sc = wr->w_softc;
368 
369 	bzero(&crie, sizeof(crie));
370 	crie.cri_alg = sc->sc_ealgo;
371 	crie.cri_klen = sc->sc_ekeylen;
372 	if (sc->sc_ealgo == CRYPTO_AES_XTS)
373 		crie.cri_klen <<= 1;
374 	if ((sc->sc_flags & G_ELI_FLAG_FIRST_KEY) != 0) {
375 		crie.cri_key = g_eli_key_hold(sc, 0,
376 		    LIST_FIRST(&sc->sc_geom->consumer)->provider->sectorsize);
377 	} else {
378 		crie.cri_key = sc->sc_ekey;
379 	}
380 	if (sc->sc_flags & G_ELI_FLAG_AUTH) {
381 		bzero(&cria, sizeof(cria));
382 		cria.cri_alg = sc->sc_aalgo;
383 		cria.cri_klen = sc->sc_akeylen;
384 		cria.cri_key = sc->sc_akey;
385 		crie.cri_next = &cria;
386 	}
387 
388 	switch (sc->sc_crypto) {
389 	case G_ELI_CRYPTO_SW:
390 		error = crypto_newsession(&wr->w_sid, &crie,
391 		    CRYPTOCAP_F_SOFTWARE);
392 		break;
393 	case G_ELI_CRYPTO_HW:
394 		error = crypto_newsession(&wr->w_sid, &crie,
395 		    CRYPTOCAP_F_HARDWARE);
396 		break;
397 	case G_ELI_CRYPTO_UNKNOWN:
398 		error = crypto_newsession(&wr->w_sid, &crie,
399 		    CRYPTOCAP_F_HARDWARE);
400 		if (error == 0) {
401 			mtx_lock(&sc->sc_queue_mtx);
402 			if (sc->sc_crypto == G_ELI_CRYPTO_UNKNOWN)
403 				sc->sc_crypto = G_ELI_CRYPTO_HW;
404 			mtx_unlock(&sc->sc_queue_mtx);
405 		} else {
406 			error = crypto_newsession(&wr->w_sid, &crie,
407 			    CRYPTOCAP_F_SOFTWARE);
408 			mtx_lock(&sc->sc_queue_mtx);
409 			if (sc->sc_crypto == G_ELI_CRYPTO_UNKNOWN)
410 				sc->sc_crypto = G_ELI_CRYPTO_SW;
411 			mtx_unlock(&sc->sc_queue_mtx);
412 		}
413 		break;
414 	default:
415 		panic("%s: invalid condition", __func__);
416 	}
417 
418 	if ((sc->sc_flags & G_ELI_FLAG_FIRST_KEY) != 0)
419 		g_eli_key_drop(sc, crie.cri_key);
420 
421 	return (error);
422 }
423 
424 static void
425 g_eli_freesession(struct g_eli_worker *wr)
426 {
427 
428 	crypto_freesession(wr->w_sid);
429 }
430 
431 static void
432 g_eli_cancel(struct g_eli_softc *sc)
433 {
434 	struct bio *bp;
435 
436 	mtx_assert(&sc->sc_queue_mtx, MA_OWNED);
437 
438 	while ((bp = bioq_takefirst(&sc->sc_queue)) != NULL) {
439 		KASSERT(bp->bio_pflags == G_ELI_NEW_BIO,
440 		    ("Not new bio when canceling (bp=%p).", bp));
441 		g_io_deliver(bp, ENXIO);
442 	}
443 }
444 
445 static struct bio *
446 g_eli_takefirst(struct g_eli_softc *sc)
447 {
448 	struct bio *bp;
449 
450 	mtx_assert(&sc->sc_queue_mtx, MA_OWNED);
451 
452 	if (!(sc->sc_flags & G_ELI_FLAG_SUSPEND))
453 		return (bioq_takefirst(&sc->sc_queue));
454 	/*
455 	 * Device suspended, so we skip new I/O requests.
456 	 */
457 	TAILQ_FOREACH(bp, &sc->sc_queue.queue, bio_queue) {
458 		if (bp->bio_pflags != G_ELI_NEW_BIO)
459 			break;
460 	}
461 	if (bp != NULL)
462 		bioq_remove(&sc->sc_queue, bp);
463 	return (bp);
464 }
465 
466 /*
467  * This is the main function for kernel worker thread when we don't have
468  * hardware acceleration and we have to do cryptography in software.
469  * Dedicated thread is needed, so we don't slow down g_up/g_down GEOM
470  * threads with crypto work.
471  */
472 static void
473 g_eli_worker(void *arg)
474 {
475 	struct g_eli_softc *sc;
476 	struct g_eli_worker *wr;
477 	struct bio *bp;
478 	int error;
479 
480 	wr = arg;
481 	sc = wr->w_softc;
482 #ifdef SMP
483 	/* Before sched_bind() to a CPU, wait for all CPUs to go on-line. */
484 	if (sc->sc_cpubind) {
485 		while (!smp_started)
486 			tsleep(wr, 0, "geli:smp", hz / 4);
487 	}
488 #endif
489 	thread_lock(curthread);
490 	sched_prio(curthread, PUSER);
491 	if (sc->sc_cpubind)
492 		sched_bind(curthread, wr->w_number % mp_ncpus);
493 	thread_unlock(curthread);
494 
495 	G_ELI_DEBUG(1, "Thread %s started.", curthread->td_proc->p_comm);
496 
497 	for (;;) {
498 		mtx_lock(&sc->sc_queue_mtx);
499 again:
500 		bp = g_eli_takefirst(sc);
501 		if (bp == NULL) {
502 			if (sc->sc_flags & G_ELI_FLAG_DESTROY) {
503 				g_eli_cancel(sc);
504 				LIST_REMOVE(wr, w_next);
505 				g_eli_freesession(wr);
506 				free(wr, M_ELI);
507 				G_ELI_DEBUG(1, "Thread %s exiting.",
508 				    curthread->td_proc->p_comm);
509 				wakeup(&sc->sc_workers);
510 				mtx_unlock(&sc->sc_queue_mtx);
511 				kproc_exit(0);
512 			}
513 			while (sc->sc_flags & G_ELI_FLAG_SUSPEND) {
514 				if (sc->sc_inflight > 0) {
515 					G_ELI_DEBUG(0, "inflight=%d",
516 					    sc->sc_inflight);
517 					/*
518 					 * We still have inflight BIOs, so
519 					 * sleep and retry.
520 					 */
521 					msleep(sc, &sc->sc_queue_mtx, PRIBIO,
522 					    "geli:inf", hz / 5);
523 					goto again;
524 				}
525 				/*
526 				 * Suspend requested, mark the worker as
527 				 * suspended and go to sleep.
528 				 */
529 				if (wr->w_active) {
530 					g_eli_freesession(wr);
531 					wr->w_active = FALSE;
532 				}
533 				wakeup(&sc->sc_workers);
534 				msleep(sc, &sc->sc_queue_mtx, PRIBIO,
535 				    "geli:suspend", 0);
536 				if (!wr->w_active &&
537 				    !(sc->sc_flags & G_ELI_FLAG_SUSPEND)) {
538 					error = g_eli_newsession(wr);
539 					KASSERT(error == 0,
540 					    ("g_eli_newsession() failed on resume (error=%d)",
541 					    error));
542 					wr->w_active = TRUE;
543 				}
544 				goto again;
545 			}
546 			msleep(sc, &sc->sc_queue_mtx, PDROP, "geli:w", 0);
547 			continue;
548 		}
549 		if (bp->bio_pflags == G_ELI_NEW_BIO)
550 			atomic_add_int(&sc->sc_inflight, 1);
551 		mtx_unlock(&sc->sc_queue_mtx);
552 		if (bp->bio_pflags == G_ELI_NEW_BIO) {
553 			bp->bio_pflags = 0;
554 			if (sc->sc_flags & G_ELI_FLAG_AUTH) {
555 				if (bp->bio_cmd == BIO_READ)
556 					g_eli_auth_read(sc, bp);
557 				else
558 					g_eli_auth_run(wr, bp);
559 			} else {
560 				if (bp->bio_cmd == BIO_READ)
561 					g_eli_crypto_read(sc, bp, 1);
562 				else
563 					g_eli_crypto_run(wr, bp);
564 			}
565 		} else {
566 			if (sc->sc_flags & G_ELI_FLAG_AUTH)
567 				g_eli_auth_run(wr, bp);
568 			else
569 				g_eli_crypto_run(wr, bp);
570 		}
571 	}
572 }
573 
574 /*
575  * Here we generate IV. It is unique for every sector.
576  */
577 void
578 g_eli_crypto_ivgen(struct g_eli_softc *sc, off_t offset, u_char *iv,
579     size_t size)
580 {
581 	uint8_t off[8];
582 
583 	if ((sc->sc_flags & G_ELI_FLAG_NATIVE_BYTE_ORDER) != 0)
584 		bcopy(&offset, off, sizeof(off));
585 	else
586 		le64enc(off, (uint64_t)offset);
587 
588 	switch (sc->sc_ealgo) {
589 	case CRYPTO_AES_XTS:
590 		bcopy(off, iv, sizeof(off));
591 		bzero(iv + sizeof(off), size - sizeof(off));
592 		break;
593 	default:
594 	    {
595 		u_char hash[SHA256_DIGEST_LENGTH];
596 		SHA256_CTX ctx;
597 
598 		/* Copy precalculated SHA256 context for IV-Key. */
599 		bcopy(&sc->sc_ivctx, &ctx, sizeof(ctx));
600 		SHA256_Update(&ctx, off, sizeof(off));
601 		SHA256_Final(hash, &ctx);
602 		bcopy(hash, iv, MIN(sizeof(hash), size));
603 		break;
604 	    }
605 	}
606 }
607 
608 int
609 g_eli_read_metadata(struct g_class *mp, struct g_provider *pp,
610     struct g_eli_metadata *md)
611 {
612 	struct g_geom *gp;
613 	struct g_consumer *cp;
614 	u_char *buf = NULL;
615 	int error;
616 
617 	g_topology_assert();
618 
619 	gp = g_new_geomf(mp, "eli:taste");
620 	gp->start = g_eli_start;
621 	gp->access = g_std_access;
622 	/*
623 	 * g_eli_read_metadata() is always called from the event thread.
624 	 * Our geom is created and destroyed in the same event, so there
625 	 * could be no orphan nor spoil event in the meantime.
626 	 */
627 	gp->orphan = g_eli_orphan_spoil_assert;
628 	gp->spoiled = g_eli_orphan_spoil_assert;
629 	cp = g_new_consumer(gp);
630 	error = g_attach(cp, pp);
631 	if (error != 0)
632 		goto end;
633 	error = g_access(cp, 1, 0, 0);
634 	if (error != 0)
635 		goto end;
636 	g_topology_unlock();
637 	buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
638 	    &error);
639 	g_topology_lock();
640 	if (buf == NULL)
641 		goto end;
642 	error = eli_metadata_decode(buf, md);
643 	if (error != 0)
644 		goto end;
645 	/* Metadata was read and decoded successfully. */
646 end:
647 	if (buf != NULL)
648 		g_free(buf);
649 	if (cp->provider != NULL) {
650 		if (cp->acr == 1)
651 			g_access(cp, -1, 0, 0);
652 		g_detach(cp);
653 	}
654 	g_destroy_consumer(cp);
655 	g_destroy_geom(gp);
656 	return (error);
657 }
658 
659 /*
660  * The function is called when we had last close on provider and user requested
661  * to close it when this situation occur.
662  */
663 static void
664 g_eli_last_close(void *arg, int flags __unused)
665 {
666 	struct g_geom *gp;
667 	char gpname[64];
668 	int error;
669 
670 	g_topology_assert();
671 	gp = arg;
672 	strlcpy(gpname, gp->name, sizeof(gpname));
673 	error = g_eli_destroy(gp->softc, TRUE);
674 	KASSERT(error == 0, ("Cannot detach %s on last close (error=%d).",
675 	    gpname, error));
676 	G_ELI_DEBUG(0, "Detached %s on last close.", gpname);
677 }
678 
679 int
680 g_eli_access(struct g_provider *pp, int dr, int dw, int de)
681 {
682 	struct g_eli_softc *sc;
683 	struct g_geom *gp;
684 
685 	gp = pp->geom;
686 	sc = gp->softc;
687 
688 	if (dw > 0) {
689 		if (sc->sc_flags & G_ELI_FLAG_RO) {
690 			/* Deny write attempts. */
691 			return (EROFS);
692 		}
693 		/* Someone is opening us for write, we need to remember that. */
694 		sc->sc_flags |= G_ELI_FLAG_WOPEN;
695 		return (0);
696 	}
697 	/* Is this the last close? */
698 	if (pp->acr + dr > 0 || pp->acw + dw > 0 || pp->ace + de > 0)
699 		return (0);
700 
701 	/*
702 	 * Automatically detach on last close if requested.
703 	 */
704 	if ((sc->sc_flags & G_ELI_FLAG_RW_DETACH) ||
705 	    (sc->sc_flags & G_ELI_FLAG_WOPEN)) {
706 		g_post_event(g_eli_last_close, gp, M_WAITOK, NULL);
707 	}
708 	return (0);
709 }
710 
711 static int
712 g_eli_cpu_is_disabled(int cpu)
713 {
714 #ifdef SMP
715 	return (CPU_ISSET(cpu, &hlt_cpus_mask));
716 #else
717 	return (0);
718 #endif
719 }
720 
721 struct g_geom *
722 g_eli_create(struct gctl_req *req, struct g_class *mp, struct g_provider *bpp,
723     const struct g_eli_metadata *md, const u_char *mkey, int nkey)
724 {
725 	struct g_eli_softc *sc;
726 	struct g_eli_worker *wr;
727 	struct g_geom *gp;
728 	struct g_provider *pp;
729 	struct g_consumer *cp;
730 	u_int i, threads;
731 	int error;
732 
733 	G_ELI_DEBUG(1, "Creating device %s%s.", bpp->name, G_ELI_SUFFIX);
734 
735 	gp = g_new_geomf(mp, "%s%s", bpp->name, G_ELI_SUFFIX);
736 	sc = malloc(sizeof(*sc), M_ELI, M_WAITOK | M_ZERO);
737 	gp->start = g_eli_start;
738 	/*
739 	 * Spoiling can happen even though we have the provider open
740 	 * exclusively, e.g. through media change events.
741 	 */
742 	gp->spoiled = g_eli_orphan;
743 	gp->orphan = g_eli_orphan;
744 	gp->dumpconf = g_eli_dumpconf;
745 	/*
746 	 * If detach-on-last-close feature is not enabled and we don't operate
747 	 * on read-only provider, we can simply use g_std_access().
748 	 */
749 	if (md->md_flags & (G_ELI_FLAG_WO_DETACH | G_ELI_FLAG_RO))
750 		gp->access = g_eli_access;
751 	else
752 		gp->access = g_std_access;
753 
754 	sc->sc_version = md->md_version;
755 	sc->sc_inflight = 0;
756 	sc->sc_crypto = G_ELI_CRYPTO_UNKNOWN;
757 	sc->sc_flags = md->md_flags;
758 	/* Backward compatibility. */
759 	if (md->md_version < G_ELI_VERSION_04)
760 		sc->sc_flags |= G_ELI_FLAG_NATIVE_BYTE_ORDER;
761 	if (md->md_version < G_ELI_VERSION_05)
762 		sc->sc_flags |= G_ELI_FLAG_SINGLE_KEY;
763 	if (md->md_version < G_ELI_VERSION_06 &&
764 	    (sc->sc_flags & G_ELI_FLAG_AUTH) != 0) {
765 		sc->sc_flags |= G_ELI_FLAG_FIRST_KEY;
766 	}
767 	if (md->md_version < G_ELI_VERSION_07)
768 		sc->sc_flags |= G_ELI_FLAG_ENC_IVKEY;
769 	sc->sc_ealgo = md->md_ealgo;
770 	sc->sc_nkey = nkey;
771 
772 	if (sc->sc_flags & G_ELI_FLAG_AUTH) {
773 		sc->sc_akeylen = sizeof(sc->sc_akey) * 8;
774 		sc->sc_aalgo = md->md_aalgo;
775 		sc->sc_alen = g_eli_hashlen(sc->sc_aalgo);
776 
777 		sc->sc_data_per_sector = bpp->sectorsize - sc->sc_alen;
778 		/*
779 		 * Some hash functions (like SHA1 and RIPEMD160) generates hash
780 		 * which length is not multiple of 128 bits, but we want data
781 		 * length to be multiple of 128, so we can encrypt without
782 		 * padding. The line below rounds down data length to multiple
783 		 * of 128 bits.
784 		 */
785 		sc->sc_data_per_sector -= sc->sc_data_per_sector % 16;
786 
787 		sc->sc_bytes_per_sector =
788 		    (md->md_sectorsize - 1) / sc->sc_data_per_sector + 1;
789 		sc->sc_bytes_per_sector *= bpp->sectorsize;
790 	}
791 
792 	gp->softc = sc;
793 	sc->sc_geom = gp;
794 
795 	bioq_init(&sc->sc_queue);
796 	mtx_init(&sc->sc_queue_mtx, "geli:queue", NULL, MTX_DEF);
797 	mtx_init(&sc->sc_ekeys_lock, "geli:ekeys", NULL, MTX_DEF);
798 
799 	pp = NULL;
800 	cp = g_new_consumer(gp);
801 	error = g_attach(cp, bpp);
802 	if (error != 0) {
803 		if (req != NULL) {
804 			gctl_error(req, "Cannot attach to %s (error=%d).",
805 			    bpp->name, error);
806 		} else {
807 			G_ELI_DEBUG(1, "Cannot attach to %s (error=%d).",
808 			    bpp->name, error);
809 		}
810 		goto failed;
811 	}
812 	/*
813 	 * Keep provider open all the time, so we can run critical tasks,
814 	 * like Master Keys deletion, without wondering if we can open
815 	 * provider or not.
816 	 * We don't open provider for writing only when user requested read-only
817 	 * access.
818 	 */
819 	if (sc->sc_flags & G_ELI_FLAG_RO)
820 		error = g_access(cp, 1, 0, 1);
821 	else
822 		error = g_access(cp, 1, 1, 1);
823 	if (error != 0) {
824 		if (req != NULL) {
825 			gctl_error(req, "Cannot access %s (error=%d).",
826 			    bpp->name, error);
827 		} else {
828 			G_ELI_DEBUG(1, "Cannot access %s (error=%d).",
829 			    bpp->name, error);
830 		}
831 		goto failed;
832 	}
833 
834 	sc->sc_sectorsize = md->md_sectorsize;
835 	sc->sc_mediasize = bpp->mediasize;
836 	if (!(sc->sc_flags & G_ELI_FLAG_ONETIME))
837 		sc->sc_mediasize -= bpp->sectorsize;
838 	if (!(sc->sc_flags & G_ELI_FLAG_AUTH))
839 		sc->sc_mediasize -= (sc->sc_mediasize % sc->sc_sectorsize);
840 	else {
841 		sc->sc_mediasize /= sc->sc_bytes_per_sector;
842 		sc->sc_mediasize *= sc->sc_sectorsize;
843 	}
844 
845 	/*
846 	 * Remember the keys in our softc structure.
847 	 */
848 	g_eli_mkey_propagate(sc, mkey);
849 	sc->sc_ekeylen = md->md_keylen;
850 
851 	LIST_INIT(&sc->sc_workers);
852 
853 	threads = g_eli_threads;
854 	if (threads == 0)
855 		threads = mp_ncpus;
856 	sc->sc_cpubind = (mp_ncpus > 1 && threads == mp_ncpus);
857 	for (i = 0; i < threads; i++) {
858 		if (g_eli_cpu_is_disabled(i)) {
859 			G_ELI_DEBUG(1, "%s: CPU %u disabled, skipping.",
860 			    bpp->name, i);
861 			continue;
862 		}
863 		wr = malloc(sizeof(*wr), M_ELI, M_WAITOK | M_ZERO);
864 		wr->w_softc = sc;
865 		wr->w_number = i;
866 		wr->w_active = TRUE;
867 
868 		error = g_eli_newsession(wr);
869 		if (error != 0) {
870 			free(wr, M_ELI);
871 			if (req != NULL) {
872 				gctl_error(req, "Cannot set up crypto session "
873 				    "for %s (error=%d).", bpp->name, error);
874 			} else {
875 				G_ELI_DEBUG(1, "Cannot set up crypto session "
876 				    "for %s (error=%d).", bpp->name, error);
877 			}
878 			goto failed;
879 		}
880 
881 		error = kproc_create(g_eli_worker, wr, &wr->w_proc, 0, 0,
882 		    "g_eli[%u] %s", i, bpp->name);
883 		if (error != 0) {
884 			g_eli_freesession(wr);
885 			free(wr, M_ELI);
886 			if (req != NULL) {
887 				gctl_error(req, "Cannot create kernel thread "
888 				    "for %s (error=%d).", bpp->name, error);
889 			} else {
890 				G_ELI_DEBUG(1, "Cannot create kernel thread "
891 				    "for %s (error=%d).", bpp->name, error);
892 			}
893 			goto failed;
894 		}
895 		LIST_INSERT_HEAD(&sc->sc_workers, wr, w_next);
896 	}
897 
898 	/*
899 	 * Create decrypted provider.
900 	 */
901 	pp = g_new_providerf(gp, "%s%s", bpp->name, G_ELI_SUFFIX);
902 	pp->mediasize = sc->sc_mediasize;
903 	pp->sectorsize = sc->sc_sectorsize;
904 
905 	g_error_provider(pp, 0);
906 
907 	G_ELI_DEBUG(0, "Device %s created.", pp->name);
908 	G_ELI_DEBUG(0, "Encryption: %s %u", g_eli_algo2str(sc->sc_ealgo),
909 	    sc->sc_ekeylen);
910 	if (sc->sc_flags & G_ELI_FLAG_AUTH)
911 		G_ELI_DEBUG(0, " Integrity: %s", g_eli_algo2str(sc->sc_aalgo));
912 	G_ELI_DEBUG(0, "    Crypto: %s",
913 	    sc->sc_crypto == G_ELI_CRYPTO_SW ? "software" : "hardware");
914 	return (gp);
915 failed:
916 	mtx_lock(&sc->sc_queue_mtx);
917 	sc->sc_flags |= G_ELI_FLAG_DESTROY;
918 	wakeup(sc);
919 	/*
920 	 * Wait for kernel threads self destruction.
921 	 */
922 	while (!LIST_EMPTY(&sc->sc_workers)) {
923 		msleep(&sc->sc_workers, &sc->sc_queue_mtx, PRIBIO,
924 		    "geli:destroy", 0);
925 	}
926 	mtx_destroy(&sc->sc_queue_mtx);
927 	if (cp->provider != NULL) {
928 		if (cp->acr == 1)
929 			g_access(cp, -1, -1, -1);
930 		g_detach(cp);
931 	}
932 	g_destroy_consumer(cp);
933 	g_destroy_geom(gp);
934 	g_eli_key_destroy(sc);
935 	bzero(sc, sizeof(*sc));
936 	free(sc, M_ELI);
937 	return (NULL);
938 }
939 
940 int
941 g_eli_destroy(struct g_eli_softc *sc, boolean_t force)
942 {
943 	struct g_geom *gp;
944 	struct g_provider *pp;
945 
946 	g_topology_assert();
947 
948 	if (sc == NULL)
949 		return (ENXIO);
950 
951 	gp = sc->sc_geom;
952 	pp = LIST_FIRST(&gp->provider);
953 	if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) {
954 		if (force) {
955 			G_ELI_DEBUG(1, "Device %s is still open, so it "
956 			    "cannot be definitely removed.", pp->name);
957 			sc->sc_flags |= G_ELI_FLAG_RW_DETACH;
958 			gp->access = g_eli_access;
959 			g_wither_provider(pp, ENXIO);
960 			return (EBUSY);
961 		} else {
962 			G_ELI_DEBUG(1,
963 			    "Device %s is still open (r%dw%de%d).", pp->name,
964 			    pp->acr, pp->acw, pp->ace);
965 			return (EBUSY);
966 		}
967 	}
968 
969 	mtx_lock(&sc->sc_queue_mtx);
970 	sc->sc_flags |= G_ELI_FLAG_DESTROY;
971 	wakeup(sc);
972 	while (!LIST_EMPTY(&sc->sc_workers)) {
973 		msleep(&sc->sc_workers, &sc->sc_queue_mtx, PRIBIO,
974 		    "geli:destroy", 0);
975 	}
976 	mtx_destroy(&sc->sc_queue_mtx);
977 	gp->softc = NULL;
978 	g_eli_key_destroy(sc);
979 	bzero(sc, sizeof(*sc));
980 	free(sc, M_ELI);
981 
982 	if (pp == NULL || (pp->acr == 0 && pp->acw == 0 && pp->ace == 0))
983 		G_ELI_DEBUG(0, "Device %s destroyed.", gp->name);
984 	g_wither_geom_close(gp, ENXIO);
985 
986 	return (0);
987 }
988 
989 static int
990 g_eli_destroy_geom(struct gctl_req *req __unused,
991     struct g_class *mp __unused, struct g_geom *gp)
992 {
993 	struct g_eli_softc *sc;
994 
995 	sc = gp->softc;
996 	return (g_eli_destroy(sc, FALSE));
997 }
998 
999 static int
1000 g_eli_keyfiles_load(struct hmac_ctx *ctx, const char *provider)
1001 {
1002 	u_char *keyfile, *data;
1003 	char *file, name[64];
1004 	size_t size;
1005 	int i;
1006 
1007 	for (i = 0; ; i++) {
1008 		snprintf(name, sizeof(name), "%s:geli_keyfile%d", provider, i);
1009 		keyfile = preload_search_by_type(name);
1010 		if (keyfile == NULL && i == 0) {
1011 			/*
1012 			 * If there is only one keyfile, allow simpler name.
1013 			 */
1014 			snprintf(name, sizeof(name), "%s:geli_keyfile", provider);
1015 			keyfile = preload_search_by_type(name);
1016 		}
1017 		if (keyfile == NULL)
1018 			return (i);	/* Return number of loaded keyfiles. */
1019 		data = preload_fetch_addr(keyfile);
1020 		if (data == NULL) {
1021 			G_ELI_DEBUG(0, "Cannot find key file data for %s.",
1022 			    name);
1023 			return (0);
1024 		}
1025 		size = preload_fetch_size(keyfile);
1026 		if (size == 0) {
1027 			G_ELI_DEBUG(0, "Cannot find key file size for %s.",
1028 			    name);
1029 			return (0);
1030 		}
1031 		file = preload_search_info(keyfile, MODINFO_NAME);
1032 		if (file == NULL) {
1033 			G_ELI_DEBUG(0, "Cannot find key file name for %s.",
1034 			    name);
1035 			return (0);
1036 		}
1037 		G_ELI_DEBUG(1, "Loaded keyfile %s for %s (type: %s).", file,
1038 		    provider, name);
1039 		g_eli_crypto_hmac_update(ctx, data, size);
1040 	}
1041 }
1042 
1043 static void
1044 g_eli_keyfiles_clear(const char *provider)
1045 {
1046 	u_char *keyfile, *data;
1047 	char name[64];
1048 	size_t size;
1049 	int i;
1050 
1051 	for (i = 0; ; i++) {
1052 		snprintf(name, sizeof(name), "%s:geli_keyfile%d", provider, i);
1053 		keyfile = preload_search_by_type(name);
1054 		if (keyfile == NULL)
1055 			return;
1056 		data = preload_fetch_addr(keyfile);
1057 		size = preload_fetch_size(keyfile);
1058 		if (data != NULL && size != 0)
1059 			bzero(data, size);
1060 	}
1061 }
1062 
1063 /*
1064  * Tasting is only made on boot.
1065  * We detect providers which should be attached before root is mounted.
1066  */
1067 static struct g_geom *
1068 g_eli_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
1069 {
1070 	struct g_eli_metadata md;
1071 	struct g_geom *gp;
1072 	struct hmac_ctx ctx;
1073 	char passphrase[256];
1074 	u_char key[G_ELI_USERKEYLEN], mkey[G_ELI_DATAIVKEYLEN];
1075 	u_int i, nkey, nkeyfiles, tries;
1076 	int error;
1077 
1078 	g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
1079 	g_topology_assert();
1080 
1081 	if (root_mounted() || g_eli_tries == 0)
1082 		return (NULL);
1083 
1084 	G_ELI_DEBUG(3, "Tasting %s.", pp->name);
1085 
1086 	error = g_eli_read_metadata(mp, pp, &md);
1087 	if (error != 0)
1088 		return (NULL);
1089 	gp = NULL;
1090 
1091 	if (strcmp(md.md_magic, G_ELI_MAGIC) != 0)
1092 		return (NULL);
1093 	if (md.md_version > G_ELI_VERSION) {
1094 		printf("geom_eli.ko module is too old to handle %s.\n",
1095 		    pp->name);
1096 		return (NULL);
1097 	}
1098 	if (md.md_provsize != pp->mediasize)
1099 		return (NULL);
1100 	/* Should we attach it on boot? */
1101 	if (!(md.md_flags & G_ELI_FLAG_BOOT))
1102 		return (NULL);
1103 	if (md.md_keys == 0x00) {
1104 		G_ELI_DEBUG(0, "No valid keys on %s.", pp->name);
1105 		return (NULL);
1106 	}
1107 	if (md.md_iterations == -1) {
1108 		/* If there is no passphrase, we try only once. */
1109 		tries = 1;
1110 	} else {
1111 		/* Ask for the passphrase no more than g_eli_tries times. */
1112 		tries = g_eli_tries;
1113 	}
1114 
1115 	for (i = 0; i <= tries; i++) {
1116 		g_eli_crypto_hmac_init(&ctx, NULL, 0);
1117 
1118 		/*
1119 		 * Load all key files.
1120 		 */
1121 		nkeyfiles = g_eli_keyfiles_load(&ctx, pp->name);
1122 
1123 		if (nkeyfiles == 0 && md.md_iterations == -1) {
1124 			/*
1125 			 * No key files and no passphrase, something is
1126 			 * definitely wrong here.
1127 			 * geli(8) doesn't allow for such situation, so assume
1128 			 * that there was really no passphrase and in that case
1129 			 * key files are no properly defined in loader.conf.
1130 			 */
1131 			G_ELI_DEBUG(0,
1132 			    "Found no key files in loader.conf for %s.",
1133 			    pp->name);
1134 			return (NULL);
1135 		}
1136 
1137 		/* Ask for the passphrase if defined. */
1138 		if (md.md_iterations >= 0) {
1139 			/* Try first with cached passphrase. */
1140 			if (i == 0) {
1141 				if (!g_eli_boot_passcache)
1142 					continue;
1143 				memcpy(passphrase, cached_passphrase,
1144 				    sizeof(passphrase));
1145 			} else {
1146 				printf("Enter passphrase for %s: ", pp->name);
1147 				cngets(passphrase, sizeof(passphrase),
1148 				    g_eli_visible_passphrase);
1149 				memcpy(cached_passphrase, passphrase,
1150 				    sizeof(passphrase));
1151 			}
1152 		}
1153 
1154 		/*
1155 		 * Prepare Derived-Key from the user passphrase.
1156 		 */
1157 		if (md.md_iterations == 0) {
1158 			g_eli_crypto_hmac_update(&ctx, md.md_salt,
1159 			    sizeof(md.md_salt));
1160 			g_eli_crypto_hmac_update(&ctx, passphrase,
1161 			    strlen(passphrase));
1162 			bzero(passphrase, sizeof(passphrase));
1163 		} else if (md.md_iterations > 0) {
1164 			u_char dkey[G_ELI_USERKEYLEN];
1165 
1166 			pkcs5v2_genkey(dkey, sizeof(dkey), md.md_salt,
1167 			    sizeof(md.md_salt), passphrase, md.md_iterations);
1168 			bzero(passphrase, sizeof(passphrase));
1169 			g_eli_crypto_hmac_update(&ctx, dkey, sizeof(dkey));
1170 			bzero(dkey, sizeof(dkey));
1171 		}
1172 
1173 		g_eli_crypto_hmac_final(&ctx, key, 0);
1174 
1175 		/*
1176 		 * Decrypt Master-Key.
1177 		 */
1178 		error = g_eli_mkey_decrypt(&md, key, mkey, &nkey);
1179 		bzero(key, sizeof(key));
1180 		if (error == -1) {
1181 			if (i == tries) {
1182 				G_ELI_DEBUG(0,
1183 				    "Wrong key for %s. No tries left.",
1184 				    pp->name);
1185 				g_eli_keyfiles_clear(pp->name);
1186 				return (NULL);
1187 			}
1188 			if (i > 0) {
1189 				G_ELI_DEBUG(0,
1190 				    "Wrong key for %s. Tries left: %u.",
1191 				    pp->name, tries - i);
1192 			}
1193 			/* Try again. */
1194 			continue;
1195 		} else if (error > 0) {
1196 			G_ELI_DEBUG(0,
1197 			    "Cannot decrypt Master Key for %s (error=%d).",
1198 			    pp->name, error);
1199 			g_eli_keyfiles_clear(pp->name);
1200 			return (NULL);
1201 		}
1202 		g_eli_keyfiles_clear(pp->name);
1203 		G_ELI_DEBUG(1, "Using Master Key %u for %s.", nkey, pp->name);
1204 		break;
1205 	}
1206 
1207 	/*
1208 	 * We have correct key, let's attach provider.
1209 	 */
1210 	gp = g_eli_create(NULL, mp, pp, &md, mkey, nkey);
1211 	bzero(mkey, sizeof(mkey));
1212 	bzero(&md, sizeof(md));
1213 	if (gp == NULL) {
1214 		G_ELI_DEBUG(0, "Cannot create device %s%s.", pp->name,
1215 		    G_ELI_SUFFIX);
1216 		return (NULL);
1217 	}
1218 	return (gp);
1219 }
1220 
1221 static void
1222 g_eli_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
1223     struct g_consumer *cp, struct g_provider *pp)
1224 {
1225 	struct g_eli_softc *sc;
1226 
1227 	g_topology_assert();
1228 	sc = gp->softc;
1229 	if (sc == NULL)
1230 		return;
1231 	if (pp != NULL || cp != NULL)
1232 		return;	/* Nothing here. */
1233 
1234 	sbuf_printf(sb, "%s<KeysTotal>%ju</KeysTotal>\n", indent,
1235 	    (uintmax_t)sc->sc_ekeys_total);
1236 	sbuf_printf(sb, "%s<KeysAllocated>%ju</KeysAllocated>\n", indent,
1237 	    (uintmax_t)sc->sc_ekeys_allocated);
1238 	sbuf_printf(sb, "%s<Flags>", indent);
1239 	if (sc->sc_flags == 0)
1240 		sbuf_printf(sb, "NONE");
1241 	else {
1242 		int first = 1;
1243 
1244 #define ADD_FLAG(flag, name)	do {					\
1245 	if (sc->sc_flags & (flag)) {					\
1246 		if (!first)						\
1247 			sbuf_printf(sb, ", ");				\
1248 		else							\
1249 			first = 0;					\
1250 		sbuf_printf(sb, name);					\
1251 	}								\
1252 } while (0)
1253 		ADD_FLAG(G_ELI_FLAG_SUSPEND, "SUSPEND");
1254 		ADD_FLAG(G_ELI_FLAG_SINGLE_KEY, "SINGLE-KEY");
1255 		ADD_FLAG(G_ELI_FLAG_NATIVE_BYTE_ORDER, "NATIVE-BYTE-ORDER");
1256 		ADD_FLAG(G_ELI_FLAG_ONETIME, "ONETIME");
1257 		ADD_FLAG(G_ELI_FLAG_BOOT, "BOOT");
1258 		ADD_FLAG(G_ELI_FLAG_WO_DETACH, "W-DETACH");
1259 		ADD_FLAG(G_ELI_FLAG_RW_DETACH, "RW-DETACH");
1260 		ADD_FLAG(G_ELI_FLAG_AUTH, "AUTH");
1261 		ADD_FLAG(G_ELI_FLAG_WOPEN, "W-OPEN");
1262 		ADD_FLAG(G_ELI_FLAG_DESTROY, "DESTROY");
1263 		ADD_FLAG(G_ELI_FLAG_RO, "READ-ONLY");
1264 		ADD_FLAG(G_ELI_FLAG_NODELETE, "NODELETE");
1265 #undef  ADD_FLAG
1266 	}
1267 	sbuf_printf(sb, "</Flags>\n");
1268 
1269 	if (!(sc->sc_flags & G_ELI_FLAG_ONETIME)) {
1270 		sbuf_printf(sb, "%s<UsedKey>%u</UsedKey>\n", indent,
1271 		    sc->sc_nkey);
1272 	}
1273 	sbuf_printf(sb, "%s<Version>%u</Version>\n", indent, sc->sc_version);
1274 	sbuf_printf(sb, "%s<Crypto>", indent);
1275 	switch (sc->sc_crypto) {
1276 	case G_ELI_CRYPTO_HW:
1277 		sbuf_printf(sb, "hardware");
1278 		break;
1279 	case G_ELI_CRYPTO_SW:
1280 		sbuf_printf(sb, "software");
1281 		break;
1282 	default:
1283 		sbuf_printf(sb, "UNKNOWN");
1284 		break;
1285 	}
1286 	sbuf_printf(sb, "</Crypto>\n");
1287 	if (sc->sc_flags & G_ELI_FLAG_AUTH) {
1288 		sbuf_printf(sb,
1289 		    "%s<AuthenticationAlgorithm>%s</AuthenticationAlgorithm>\n",
1290 		    indent, g_eli_algo2str(sc->sc_aalgo));
1291 	}
1292 	sbuf_printf(sb, "%s<KeyLength>%u</KeyLength>\n", indent,
1293 	    sc->sc_ekeylen);
1294 	sbuf_printf(sb, "%s<EncryptionAlgorithm>%s</EncryptionAlgorithm>\n",
1295 	    indent, g_eli_algo2str(sc->sc_ealgo));
1296 	sbuf_printf(sb, "%s<State>%s</State>\n", indent,
1297 	    (sc->sc_flags & G_ELI_FLAG_SUSPEND) ? "SUSPENDED" : "ACTIVE");
1298 }
1299 
1300 static void
1301 g_eli_shutdown_pre_sync(void *arg, int howto)
1302 {
1303 	struct g_class *mp;
1304 	struct g_geom *gp, *gp2;
1305 	struct g_provider *pp;
1306 	struct g_eli_softc *sc;
1307 	int error;
1308 
1309 	mp = arg;
1310 	DROP_GIANT();
1311 	g_topology_lock();
1312 	LIST_FOREACH_SAFE(gp, &mp->geom, geom, gp2) {
1313 		sc = gp->softc;
1314 		if (sc == NULL)
1315 			continue;
1316 		pp = LIST_FIRST(&gp->provider);
1317 		KASSERT(pp != NULL, ("No provider? gp=%p (%s)", gp, gp->name));
1318 		if (pp->acr + pp->acw + pp->ace == 0)
1319 			error = g_eli_destroy(sc, TRUE);
1320 		else {
1321 			sc->sc_flags |= G_ELI_FLAG_RW_DETACH;
1322 			gp->access = g_eli_access;
1323 		}
1324 	}
1325 	g_topology_unlock();
1326 	PICKUP_GIANT();
1327 }
1328 
1329 static void
1330 g_eli_init(struct g_class *mp)
1331 {
1332 
1333 	g_eli_pre_sync = EVENTHANDLER_REGISTER(shutdown_pre_sync,
1334 	    g_eli_shutdown_pre_sync, mp, SHUTDOWN_PRI_FIRST);
1335 	if (g_eli_pre_sync == NULL)
1336 		G_ELI_DEBUG(0, "Warning! Cannot register shutdown event.");
1337 }
1338 
1339 static void
1340 g_eli_fini(struct g_class *mp)
1341 {
1342 
1343 	if (g_eli_pre_sync != NULL)
1344 		EVENTHANDLER_DEREGISTER(shutdown_pre_sync, g_eli_pre_sync);
1345 }
1346 
1347 DECLARE_GEOM_CLASS(g_eli_class, g_eli);
1348 MODULE_DEPEND(g_eli, crypto, 1, 1, 1);
1349