xref: /freebsd/sys/geom/eli/g_eli.c (revision f4b37ed0f8b307b1f3f0f630ca725d68f1dff30d)
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)
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", __func__);
210 		pbp->bio_completed = 0;
211 		if (pbp->bio_driver2 != NULL) {
212 			free(pbp->bio_driver2, M_ELI);
213 			pbp->bio_driver2 = NULL;
214 		}
215 		g_io_deliver(pbp, pbp->bio_error);
216 		atomic_subtract_int(&sc->sc_inflight, 1);
217 		return;
218 	}
219 	mtx_lock(&sc->sc_queue_mtx);
220 	bioq_insert_tail(&sc->sc_queue, pbp);
221 	mtx_unlock(&sc->sc_queue_mtx);
222 	wakeup(sc);
223 }
224 
225 /*
226  * The function is called after we encrypt and write data.
227  *
228  * g_eli_start -> g_eli_crypto_run -> g_eli_crypto_write_done -> g_io_request -> G_ELI_WRITE_DONE -> g_io_deliver
229  */
230 void
231 g_eli_write_done(struct bio *bp)
232 {
233 	struct g_eli_softc *sc;
234 	struct bio *pbp;
235 
236 	G_ELI_LOGREQ(2, bp, "Request done.");
237 	pbp = bp->bio_parent;
238 	if (pbp->bio_error == 0) {
239 		if (bp->bio_error != 0)
240 			pbp->bio_error = bp->bio_error;
241 	}
242 	g_destroy_bio(bp);
243 	/*
244 	 * Do we have all sectors already?
245 	 */
246 	pbp->bio_inbed++;
247 	if (pbp->bio_inbed < pbp->bio_children)
248 		return;
249 	free(pbp->bio_driver2, M_ELI);
250 	pbp->bio_driver2 = NULL;
251 	if (pbp->bio_error != 0) {
252 		G_ELI_LOGREQ(0, pbp, "Crypto WRITE request failed (error=%d).",
253 		    pbp->bio_error);
254 		pbp->bio_completed = 0;
255 	}
256 	/*
257 	 * Write is finished, send it up.
258 	 */
259 	pbp->bio_completed = pbp->bio_length;
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 		 * We could eventually support BIO_DELETE request.
316 		 * It could be done by overwritting requested sector with
317 		 * random data g_eli_overwrites number of times.
318 		 */
319 	default:
320 		g_io_deliver(bp, EOPNOTSUPP);
321 		return;
322 	}
323 	cbp = g_clone_bio(bp);
324 	if (cbp == NULL) {
325 		g_io_deliver(bp, ENOMEM);
326 		return;
327 	}
328 	bp->bio_driver1 = cbp;
329 	bp->bio_pflags = G_ELI_NEW_BIO;
330 	switch (bp->bio_cmd) {
331 	case BIO_READ:
332 		if (!(sc->sc_flags & G_ELI_FLAG_AUTH)) {
333 			g_eli_crypto_read(sc, bp, 0);
334 			break;
335 		}
336 		/* FALLTHROUGH */
337 	case BIO_WRITE:
338 		mtx_lock(&sc->sc_queue_mtx);
339 		bioq_insert_tail(&sc->sc_queue, bp);
340 		mtx_unlock(&sc->sc_queue_mtx);
341 		wakeup(sc);
342 		break;
343 	case BIO_GETATTR:
344 	case BIO_FLUSH:
345 		cbp->bio_done = g_std_done;
346 		cp = LIST_FIRST(&sc->sc_geom->consumer);
347 		cbp->bio_to = cp->provider;
348 		G_ELI_LOGREQ(2, cbp, "Sending request.");
349 		g_io_request(cbp, cp);
350 		break;
351 	}
352 }
353 
354 static int
355 g_eli_newsession(struct g_eli_worker *wr)
356 {
357 	struct g_eli_softc *sc;
358 	struct cryptoini crie, cria;
359 	int error;
360 
361 	sc = wr->w_softc;
362 
363 	bzero(&crie, sizeof(crie));
364 	crie.cri_alg = sc->sc_ealgo;
365 	crie.cri_klen = sc->sc_ekeylen;
366 	if (sc->sc_ealgo == CRYPTO_AES_XTS)
367 		crie.cri_klen <<= 1;
368 	if ((sc->sc_flags & G_ELI_FLAG_FIRST_KEY) != 0) {
369 		crie.cri_key = g_eli_key_hold(sc, 0,
370 		    LIST_FIRST(&sc->sc_geom->consumer)->provider->sectorsize);
371 	} else {
372 		crie.cri_key = sc->sc_ekey;
373 	}
374 	if (sc->sc_flags & G_ELI_FLAG_AUTH) {
375 		bzero(&cria, sizeof(cria));
376 		cria.cri_alg = sc->sc_aalgo;
377 		cria.cri_klen = sc->sc_akeylen;
378 		cria.cri_key = sc->sc_akey;
379 		crie.cri_next = &cria;
380 	}
381 
382 	switch (sc->sc_crypto) {
383 	case G_ELI_CRYPTO_SW:
384 		error = crypto_newsession(&wr->w_sid, &crie,
385 		    CRYPTOCAP_F_SOFTWARE);
386 		break;
387 	case G_ELI_CRYPTO_HW:
388 		error = crypto_newsession(&wr->w_sid, &crie,
389 		    CRYPTOCAP_F_HARDWARE);
390 		break;
391 	case G_ELI_CRYPTO_UNKNOWN:
392 		error = crypto_newsession(&wr->w_sid, &crie,
393 		    CRYPTOCAP_F_HARDWARE);
394 		if (error == 0) {
395 			mtx_lock(&sc->sc_queue_mtx);
396 			if (sc->sc_crypto == G_ELI_CRYPTO_UNKNOWN)
397 				sc->sc_crypto = G_ELI_CRYPTO_HW;
398 			mtx_unlock(&sc->sc_queue_mtx);
399 		} else {
400 			error = crypto_newsession(&wr->w_sid, &crie,
401 			    CRYPTOCAP_F_SOFTWARE);
402 			mtx_lock(&sc->sc_queue_mtx);
403 			if (sc->sc_crypto == G_ELI_CRYPTO_UNKNOWN)
404 				sc->sc_crypto = G_ELI_CRYPTO_SW;
405 			mtx_unlock(&sc->sc_queue_mtx);
406 		}
407 		break;
408 	default:
409 		panic("%s: invalid condition", __func__);
410 	}
411 
412 	if ((sc->sc_flags & G_ELI_FLAG_FIRST_KEY) != 0)
413 		g_eli_key_drop(sc, crie.cri_key);
414 
415 	return (error);
416 }
417 
418 static void
419 g_eli_freesession(struct g_eli_worker *wr)
420 {
421 
422 	crypto_freesession(wr->w_sid);
423 }
424 
425 static void
426 g_eli_cancel(struct g_eli_softc *sc)
427 {
428 	struct bio *bp;
429 
430 	mtx_assert(&sc->sc_queue_mtx, MA_OWNED);
431 
432 	while ((bp = bioq_takefirst(&sc->sc_queue)) != NULL) {
433 		KASSERT(bp->bio_pflags == G_ELI_NEW_BIO,
434 		    ("Not new bio when canceling (bp=%p).", bp));
435 		g_io_deliver(bp, ENXIO);
436 	}
437 }
438 
439 static struct bio *
440 g_eli_takefirst(struct g_eli_softc *sc)
441 {
442 	struct bio *bp;
443 
444 	mtx_assert(&sc->sc_queue_mtx, MA_OWNED);
445 
446 	if (!(sc->sc_flags & G_ELI_FLAG_SUSPEND))
447 		return (bioq_takefirst(&sc->sc_queue));
448 	/*
449 	 * Device suspended, so we skip new I/O requests.
450 	 */
451 	TAILQ_FOREACH(bp, &sc->sc_queue.queue, bio_queue) {
452 		if (bp->bio_pflags != G_ELI_NEW_BIO)
453 			break;
454 	}
455 	if (bp != NULL)
456 		bioq_remove(&sc->sc_queue, bp);
457 	return (bp);
458 }
459 
460 /*
461  * This is the main function for kernel worker thread when we don't have
462  * hardware acceleration and we have to do cryptography in software.
463  * Dedicated thread is needed, so we don't slow down g_up/g_down GEOM
464  * threads with crypto work.
465  */
466 static void
467 g_eli_worker(void *arg)
468 {
469 	struct g_eli_softc *sc;
470 	struct g_eli_worker *wr;
471 	struct bio *bp;
472 	int error;
473 
474 	wr = arg;
475 	sc = wr->w_softc;
476 #ifdef SMP
477 	/* Before sched_bind() to a CPU, wait for all CPUs to go on-line. */
478 	if (sc->sc_cpubind) {
479 		while (!smp_started)
480 			tsleep(wr, 0, "geli:smp", hz / 4);
481 	}
482 #endif
483 	thread_lock(curthread);
484 	sched_prio(curthread, PUSER);
485 	if (sc->sc_cpubind)
486 		sched_bind(curthread, wr->w_number % mp_ncpus);
487 	thread_unlock(curthread);
488 
489 	G_ELI_DEBUG(1, "Thread %s started.", curthread->td_proc->p_comm);
490 
491 	for (;;) {
492 		mtx_lock(&sc->sc_queue_mtx);
493 again:
494 		bp = g_eli_takefirst(sc);
495 		if (bp == NULL) {
496 			if (sc->sc_flags & G_ELI_FLAG_DESTROY) {
497 				g_eli_cancel(sc);
498 				LIST_REMOVE(wr, w_next);
499 				g_eli_freesession(wr);
500 				free(wr, M_ELI);
501 				G_ELI_DEBUG(1, "Thread %s exiting.",
502 				    curthread->td_proc->p_comm);
503 				wakeup(&sc->sc_workers);
504 				mtx_unlock(&sc->sc_queue_mtx);
505 				kproc_exit(0);
506 			}
507 			while (sc->sc_flags & G_ELI_FLAG_SUSPEND) {
508 				if (sc->sc_inflight > 0) {
509 					G_ELI_DEBUG(0, "inflight=%d",
510 					    sc->sc_inflight);
511 					/*
512 					 * We still have inflight BIOs, so
513 					 * sleep and retry.
514 					 */
515 					msleep(sc, &sc->sc_queue_mtx, PRIBIO,
516 					    "geli:inf", hz / 5);
517 					goto again;
518 				}
519 				/*
520 				 * Suspend requested, mark the worker as
521 				 * suspended and go to sleep.
522 				 */
523 				if (wr->w_active) {
524 					g_eli_freesession(wr);
525 					wr->w_active = FALSE;
526 				}
527 				wakeup(&sc->sc_workers);
528 				msleep(sc, &sc->sc_queue_mtx, PRIBIO,
529 				    "geli:suspend", 0);
530 				if (!wr->w_active &&
531 				    !(sc->sc_flags & G_ELI_FLAG_SUSPEND)) {
532 					error = g_eli_newsession(wr);
533 					KASSERT(error == 0,
534 					    ("g_eli_newsession() failed on resume (error=%d)",
535 					    error));
536 					wr->w_active = TRUE;
537 				}
538 				goto again;
539 			}
540 			msleep(sc, &sc->sc_queue_mtx, PDROP, "geli:w", 0);
541 			continue;
542 		}
543 		if (bp->bio_pflags == G_ELI_NEW_BIO)
544 			atomic_add_int(&sc->sc_inflight, 1);
545 		mtx_unlock(&sc->sc_queue_mtx);
546 		if (bp->bio_pflags == G_ELI_NEW_BIO) {
547 			bp->bio_pflags = 0;
548 			if (sc->sc_flags & G_ELI_FLAG_AUTH) {
549 				if (bp->bio_cmd == BIO_READ)
550 					g_eli_auth_read(sc, bp);
551 				else
552 					g_eli_auth_run(wr, bp);
553 			} else {
554 				if (bp->bio_cmd == BIO_READ)
555 					g_eli_crypto_read(sc, bp, 1);
556 				else
557 					g_eli_crypto_run(wr, bp);
558 			}
559 		} else {
560 			if (sc->sc_flags & G_ELI_FLAG_AUTH)
561 				g_eli_auth_run(wr, bp);
562 			else
563 				g_eli_crypto_run(wr, bp);
564 		}
565 	}
566 }
567 
568 /*
569  * Here we generate IV. It is unique for every sector.
570  */
571 void
572 g_eli_crypto_ivgen(struct g_eli_softc *sc, off_t offset, u_char *iv,
573     size_t size)
574 {
575 	uint8_t off[8];
576 
577 	if ((sc->sc_flags & G_ELI_FLAG_NATIVE_BYTE_ORDER) != 0)
578 		bcopy(&offset, off, sizeof(off));
579 	else
580 		le64enc(off, (uint64_t)offset);
581 
582 	switch (sc->sc_ealgo) {
583 	case CRYPTO_AES_XTS:
584 		bcopy(off, iv, sizeof(off));
585 		bzero(iv + sizeof(off), size - sizeof(off));
586 		break;
587 	default:
588 	    {
589 		u_char hash[SHA256_DIGEST_LENGTH];
590 		SHA256_CTX ctx;
591 
592 		/* Copy precalculated SHA256 context for IV-Key. */
593 		bcopy(&sc->sc_ivctx, &ctx, sizeof(ctx));
594 		SHA256_Update(&ctx, off, sizeof(off));
595 		SHA256_Final(hash, &ctx);
596 		bcopy(hash, iv, MIN(sizeof(hash), size));
597 		break;
598 	    }
599 	}
600 }
601 
602 int
603 g_eli_read_metadata(struct g_class *mp, struct g_provider *pp,
604     struct g_eli_metadata *md)
605 {
606 	struct g_geom *gp;
607 	struct g_consumer *cp;
608 	u_char *buf = NULL;
609 	int error;
610 
611 	g_topology_assert();
612 
613 	gp = g_new_geomf(mp, "eli:taste");
614 	gp->start = g_eli_start;
615 	gp->access = g_std_access;
616 	/*
617 	 * g_eli_read_metadata() is always called from the event thread.
618 	 * Our geom is created and destroyed in the same event, so there
619 	 * could be no orphan nor spoil event in the meantime.
620 	 */
621 	gp->orphan = g_eli_orphan_spoil_assert;
622 	gp->spoiled = g_eli_orphan_spoil_assert;
623 	cp = g_new_consumer(gp);
624 	error = g_attach(cp, pp);
625 	if (error != 0)
626 		goto end;
627 	error = g_access(cp, 1, 0, 0);
628 	if (error != 0)
629 		goto end;
630 	g_topology_unlock();
631 	buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
632 	    &error);
633 	g_topology_lock();
634 	if (buf == NULL)
635 		goto end;
636 	error = eli_metadata_decode(buf, md);
637 	if (error != 0)
638 		goto end;
639 	/* Metadata was read and decoded successfully. */
640 end:
641 	if (buf != NULL)
642 		g_free(buf);
643 	if (cp->provider != NULL) {
644 		if (cp->acr == 1)
645 			g_access(cp, -1, 0, 0);
646 		g_detach(cp);
647 	}
648 	g_destroy_consumer(cp);
649 	g_destroy_geom(gp);
650 	return (error);
651 }
652 
653 /*
654  * The function is called when we had last close on provider and user requested
655  * to close it when this situation occur.
656  */
657 static void
658 g_eli_last_close(void *arg, int flags __unused)
659 {
660 	struct g_geom *gp;
661 	char gpname[64];
662 	int error;
663 
664 	g_topology_assert();
665 	gp = arg;
666 	strlcpy(gpname, gp->name, sizeof(gpname));
667 	error = g_eli_destroy(gp->softc, TRUE);
668 	KASSERT(error == 0, ("Cannot detach %s on last close (error=%d).",
669 	    gpname, error));
670 	G_ELI_DEBUG(0, "Detached %s on last close.", gpname);
671 }
672 
673 int
674 g_eli_access(struct g_provider *pp, int dr, int dw, int de)
675 {
676 	struct g_eli_softc *sc;
677 	struct g_geom *gp;
678 
679 	gp = pp->geom;
680 	sc = gp->softc;
681 
682 	if (dw > 0) {
683 		if (sc->sc_flags & G_ELI_FLAG_RO) {
684 			/* Deny write attempts. */
685 			return (EROFS);
686 		}
687 		/* Someone is opening us for write, we need to remember that. */
688 		sc->sc_flags |= G_ELI_FLAG_WOPEN;
689 		return (0);
690 	}
691 	/* Is this the last close? */
692 	if (pp->acr + dr > 0 || pp->acw + dw > 0 || pp->ace + de > 0)
693 		return (0);
694 
695 	/*
696 	 * Automatically detach on last close if requested.
697 	 */
698 	if ((sc->sc_flags & G_ELI_FLAG_RW_DETACH) ||
699 	    (sc->sc_flags & G_ELI_FLAG_WOPEN)) {
700 		g_post_event(g_eli_last_close, gp, M_WAITOK, NULL);
701 	}
702 	return (0);
703 }
704 
705 static int
706 g_eli_cpu_is_disabled(int cpu)
707 {
708 #ifdef SMP
709 	return (CPU_ISSET(cpu, &hlt_cpus_mask));
710 #else
711 	return (0);
712 #endif
713 }
714 
715 struct g_geom *
716 g_eli_create(struct gctl_req *req, struct g_class *mp, struct g_provider *bpp,
717     const struct g_eli_metadata *md, const u_char *mkey, int nkey)
718 {
719 	struct g_eli_softc *sc;
720 	struct g_eli_worker *wr;
721 	struct g_geom *gp;
722 	struct g_provider *pp;
723 	struct g_consumer *cp;
724 	u_int i, threads;
725 	int error;
726 
727 	G_ELI_DEBUG(1, "Creating device %s%s.", bpp->name, G_ELI_SUFFIX);
728 
729 	gp = g_new_geomf(mp, "%s%s", bpp->name, G_ELI_SUFFIX);
730 	sc = malloc(sizeof(*sc), M_ELI, M_WAITOK | M_ZERO);
731 	gp->start = g_eli_start;
732 	/*
733 	 * Spoiling can happen even though we have the provider open
734 	 * exclusively, e.g. through media change events.
735 	 */
736 	gp->spoiled = g_eli_orphan;
737 	gp->orphan = g_eli_orphan;
738 	gp->dumpconf = g_eli_dumpconf;
739 	/*
740 	 * If detach-on-last-close feature is not enabled and we don't operate
741 	 * on read-only provider, we can simply use g_std_access().
742 	 */
743 	if (md->md_flags & (G_ELI_FLAG_WO_DETACH | G_ELI_FLAG_RO))
744 		gp->access = g_eli_access;
745 	else
746 		gp->access = g_std_access;
747 
748 	sc->sc_version = md->md_version;
749 	sc->sc_inflight = 0;
750 	sc->sc_crypto = G_ELI_CRYPTO_UNKNOWN;
751 	sc->sc_flags = md->md_flags;
752 	/* Backward compatibility. */
753 	if (md->md_version < G_ELI_VERSION_04)
754 		sc->sc_flags |= G_ELI_FLAG_NATIVE_BYTE_ORDER;
755 	if (md->md_version < G_ELI_VERSION_05)
756 		sc->sc_flags |= G_ELI_FLAG_SINGLE_KEY;
757 	if (md->md_version < G_ELI_VERSION_06 &&
758 	    (sc->sc_flags & G_ELI_FLAG_AUTH) != 0) {
759 		sc->sc_flags |= G_ELI_FLAG_FIRST_KEY;
760 	}
761 	if (md->md_version < G_ELI_VERSION_07)
762 		sc->sc_flags |= G_ELI_FLAG_ENC_IVKEY;
763 	sc->sc_ealgo = md->md_ealgo;
764 	sc->sc_nkey = nkey;
765 
766 	if (sc->sc_flags & G_ELI_FLAG_AUTH) {
767 		sc->sc_akeylen = sizeof(sc->sc_akey) * 8;
768 		sc->sc_aalgo = md->md_aalgo;
769 		sc->sc_alen = g_eli_hashlen(sc->sc_aalgo);
770 
771 		sc->sc_data_per_sector = bpp->sectorsize - sc->sc_alen;
772 		/*
773 		 * Some hash functions (like SHA1 and RIPEMD160) generates hash
774 		 * which length is not multiple of 128 bits, but we want data
775 		 * length to be multiple of 128, so we can encrypt without
776 		 * padding. The line below rounds down data length to multiple
777 		 * of 128 bits.
778 		 */
779 		sc->sc_data_per_sector -= sc->sc_data_per_sector % 16;
780 
781 		sc->sc_bytes_per_sector =
782 		    (md->md_sectorsize - 1) / sc->sc_data_per_sector + 1;
783 		sc->sc_bytes_per_sector *= bpp->sectorsize;
784 	}
785 
786 	gp->softc = sc;
787 	sc->sc_geom = gp;
788 
789 	bioq_init(&sc->sc_queue);
790 	mtx_init(&sc->sc_queue_mtx, "geli:queue", NULL, MTX_DEF);
791 	mtx_init(&sc->sc_ekeys_lock, "geli:ekeys", NULL, MTX_DEF);
792 
793 	pp = NULL;
794 	cp = g_new_consumer(gp);
795 	error = g_attach(cp, bpp);
796 	if (error != 0) {
797 		if (req != NULL) {
798 			gctl_error(req, "Cannot attach to %s (error=%d).",
799 			    bpp->name, error);
800 		} else {
801 			G_ELI_DEBUG(1, "Cannot attach to %s (error=%d).",
802 			    bpp->name, error);
803 		}
804 		goto failed;
805 	}
806 	/*
807 	 * Keep provider open all the time, so we can run critical tasks,
808 	 * like Master Keys deletion, without wondering if we can open
809 	 * provider or not.
810 	 * We don't open provider for writing only when user requested read-only
811 	 * access.
812 	 */
813 	if (sc->sc_flags & G_ELI_FLAG_RO)
814 		error = g_access(cp, 1, 0, 1);
815 	else
816 		error = g_access(cp, 1, 1, 1);
817 	if (error != 0) {
818 		if (req != NULL) {
819 			gctl_error(req, "Cannot access %s (error=%d).",
820 			    bpp->name, error);
821 		} else {
822 			G_ELI_DEBUG(1, "Cannot access %s (error=%d).",
823 			    bpp->name, error);
824 		}
825 		goto failed;
826 	}
827 
828 	sc->sc_sectorsize = md->md_sectorsize;
829 	sc->sc_mediasize = bpp->mediasize;
830 	if (!(sc->sc_flags & G_ELI_FLAG_ONETIME))
831 		sc->sc_mediasize -= bpp->sectorsize;
832 	if (!(sc->sc_flags & G_ELI_FLAG_AUTH))
833 		sc->sc_mediasize -= (sc->sc_mediasize % sc->sc_sectorsize);
834 	else {
835 		sc->sc_mediasize /= sc->sc_bytes_per_sector;
836 		sc->sc_mediasize *= sc->sc_sectorsize;
837 	}
838 
839 	/*
840 	 * Remember the keys in our softc structure.
841 	 */
842 	g_eli_mkey_propagate(sc, mkey);
843 	sc->sc_ekeylen = md->md_keylen;
844 
845 	LIST_INIT(&sc->sc_workers);
846 
847 	threads = g_eli_threads;
848 	if (threads == 0)
849 		threads = mp_ncpus;
850 	sc->sc_cpubind = (mp_ncpus > 1 && threads == mp_ncpus);
851 	for (i = 0; i < threads; i++) {
852 		if (g_eli_cpu_is_disabled(i)) {
853 			G_ELI_DEBUG(1, "%s: CPU %u disabled, skipping.",
854 			    bpp->name, i);
855 			continue;
856 		}
857 		wr = malloc(sizeof(*wr), M_ELI, M_WAITOK | M_ZERO);
858 		wr->w_softc = sc;
859 		wr->w_number = i;
860 		wr->w_active = TRUE;
861 
862 		error = g_eli_newsession(wr);
863 		if (error != 0) {
864 			free(wr, M_ELI);
865 			if (req != NULL) {
866 				gctl_error(req, "Cannot set up crypto session "
867 				    "for %s (error=%d).", bpp->name, error);
868 			} else {
869 				G_ELI_DEBUG(1, "Cannot set up crypto session "
870 				    "for %s (error=%d).", bpp->name, error);
871 			}
872 			goto failed;
873 		}
874 
875 		error = kproc_create(g_eli_worker, wr, &wr->w_proc, 0, 0,
876 		    "g_eli[%u] %s", i, bpp->name);
877 		if (error != 0) {
878 			g_eli_freesession(wr);
879 			free(wr, M_ELI);
880 			if (req != NULL) {
881 				gctl_error(req, "Cannot create kernel thread "
882 				    "for %s (error=%d).", bpp->name, error);
883 			} else {
884 				G_ELI_DEBUG(1, "Cannot create kernel thread "
885 				    "for %s (error=%d).", bpp->name, error);
886 			}
887 			goto failed;
888 		}
889 		LIST_INSERT_HEAD(&sc->sc_workers, wr, w_next);
890 	}
891 
892 	/*
893 	 * Create decrypted provider.
894 	 */
895 	pp = g_new_providerf(gp, "%s%s", bpp->name, G_ELI_SUFFIX);
896 	pp->mediasize = sc->sc_mediasize;
897 	pp->sectorsize = sc->sc_sectorsize;
898 
899 	g_error_provider(pp, 0);
900 
901 	G_ELI_DEBUG(0, "Device %s created.", pp->name);
902 	G_ELI_DEBUG(0, "Encryption: %s %u", g_eli_algo2str(sc->sc_ealgo),
903 	    sc->sc_ekeylen);
904 	if (sc->sc_flags & G_ELI_FLAG_AUTH)
905 		G_ELI_DEBUG(0, " Integrity: %s", g_eli_algo2str(sc->sc_aalgo));
906 	G_ELI_DEBUG(0, "    Crypto: %s",
907 	    sc->sc_crypto == G_ELI_CRYPTO_SW ? "software" : "hardware");
908 	return (gp);
909 failed:
910 	mtx_lock(&sc->sc_queue_mtx);
911 	sc->sc_flags |= G_ELI_FLAG_DESTROY;
912 	wakeup(sc);
913 	/*
914 	 * Wait for kernel threads self destruction.
915 	 */
916 	while (!LIST_EMPTY(&sc->sc_workers)) {
917 		msleep(&sc->sc_workers, &sc->sc_queue_mtx, PRIBIO,
918 		    "geli:destroy", 0);
919 	}
920 	mtx_destroy(&sc->sc_queue_mtx);
921 	if (cp->provider != NULL) {
922 		if (cp->acr == 1)
923 			g_access(cp, -1, -1, -1);
924 		g_detach(cp);
925 	}
926 	g_destroy_consumer(cp);
927 	g_destroy_geom(gp);
928 	g_eli_key_destroy(sc);
929 	bzero(sc, sizeof(*sc));
930 	free(sc, M_ELI);
931 	return (NULL);
932 }
933 
934 int
935 g_eli_destroy(struct g_eli_softc *sc, boolean_t force)
936 {
937 	struct g_geom *gp;
938 	struct g_provider *pp;
939 
940 	g_topology_assert();
941 
942 	if (sc == NULL)
943 		return (ENXIO);
944 
945 	gp = sc->sc_geom;
946 	pp = LIST_FIRST(&gp->provider);
947 	if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) {
948 		if (force) {
949 			G_ELI_DEBUG(1, "Device %s is still open, so it "
950 			    "cannot be definitely removed.", pp->name);
951 			sc->sc_flags |= G_ELI_FLAG_RW_DETACH;
952 			gp->access = g_eli_access;
953 			g_wither_provider(pp, ENXIO);
954 			return (EBUSY);
955 		} else {
956 			G_ELI_DEBUG(1,
957 			    "Device %s is still open (r%dw%de%d).", pp->name,
958 			    pp->acr, pp->acw, pp->ace);
959 			return (EBUSY);
960 		}
961 	}
962 
963 	mtx_lock(&sc->sc_queue_mtx);
964 	sc->sc_flags |= G_ELI_FLAG_DESTROY;
965 	wakeup(sc);
966 	while (!LIST_EMPTY(&sc->sc_workers)) {
967 		msleep(&sc->sc_workers, &sc->sc_queue_mtx, PRIBIO,
968 		    "geli:destroy", 0);
969 	}
970 	mtx_destroy(&sc->sc_queue_mtx);
971 	gp->softc = NULL;
972 	g_eli_key_destroy(sc);
973 	bzero(sc, sizeof(*sc));
974 	free(sc, M_ELI);
975 
976 	if (pp == NULL || (pp->acr == 0 && pp->acw == 0 && pp->ace == 0))
977 		G_ELI_DEBUG(0, "Device %s destroyed.", gp->name);
978 	g_wither_geom_close(gp, ENXIO);
979 
980 	return (0);
981 }
982 
983 static int
984 g_eli_destroy_geom(struct gctl_req *req __unused,
985     struct g_class *mp __unused, struct g_geom *gp)
986 {
987 	struct g_eli_softc *sc;
988 
989 	sc = gp->softc;
990 	return (g_eli_destroy(sc, FALSE));
991 }
992 
993 static int
994 g_eli_keyfiles_load(struct hmac_ctx *ctx, const char *provider)
995 {
996 	u_char *keyfile, *data;
997 	char *file, name[64];
998 	size_t size;
999 	int i;
1000 
1001 	for (i = 0; ; i++) {
1002 		snprintf(name, sizeof(name), "%s:geli_keyfile%d", provider, i);
1003 		keyfile = preload_search_by_type(name);
1004 		if (keyfile == NULL && i == 0) {
1005 			/*
1006 			 * If there is only one keyfile, allow simpler name.
1007 			 */
1008 			snprintf(name, sizeof(name), "%s:geli_keyfile", provider);
1009 			keyfile = preload_search_by_type(name);
1010 		}
1011 		if (keyfile == NULL)
1012 			return (i);	/* Return number of loaded keyfiles. */
1013 		data = preload_fetch_addr(keyfile);
1014 		if (data == NULL) {
1015 			G_ELI_DEBUG(0, "Cannot find key file data for %s.",
1016 			    name);
1017 			return (0);
1018 		}
1019 		size = preload_fetch_size(keyfile);
1020 		if (size == 0) {
1021 			G_ELI_DEBUG(0, "Cannot find key file size for %s.",
1022 			    name);
1023 			return (0);
1024 		}
1025 		file = preload_search_info(keyfile, MODINFO_NAME);
1026 		if (file == NULL) {
1027 			G_ELI_DEBUG(0, "Cannot find key file name for %s.",
1028 			    name);
1029 			return (0);
1030 		}
1031 		G_ELI_DEBUG(1, "Loaded keyfile %s for %s (type: %s).", file,
1032 		    provider, name);
1033 		g_eli_crypto_hmac_update(ctx, data, size);
1034 	}
1035 }
1036 
1037 static void
1038 g_eli_keyfiles_clear(const char *provider)
1039 {
1040 	u_char *keyfile, *data;
1041 	char name[64];
1042 	size_t size;
1043 	int i;
1044 
1045 	for (i = 0; ; i++) {
1046 		snprintf(name, sizeof(name), "%s:geli_keyfile%d", provider, i);
1047 		keyfile = preload_search_by_type(name);
1048 		if (keyfile == NULL)
1049 			return;
1050 		data = preload_fetch_addr(keyfile);
1051 		size = preload_fetch_size(keyfile);
1052 		if (data != NULL && size != 0)
1053 			bzero(data, size);
1054 	}
1055 }
1056 
1057 /*
1058  * Tasting is only made on boot.
1059  * We detect providers which should be attached before root is mounted.
1060  */
1061 static struct g_geom *
1062 g_eli_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
1063 {
1064 	struct g_eli_metadata md;
1065 	struct g_geom *gp;
1066 	struct hmac_ctx ctx;
1067 	char passphrase[256];
1068 	u_char key[G_ELI_USERKEYLEN], mkey[G_ELI_DATAIVKEYLEN];
1069 	u_int i, nkey, nkeyfiles, tries;
1070 	int error;
1071 
1072 	g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
1073 	g_topology_assert();
1074 
1075 	if (root_mounted() || g_eli_tries == 0)
1076 		return (NULL);
1077 
1078 	G_ELI_DEBUG(3, "Tasting %s.", pp->name);
1079 
1080 	error = g_eli_read_metadata(mp, pp, &md);
1081 	if (error != 0)
1082 		return (NULL);
1083 	gp = NULL;
1084 
1085 	if (strcmp(md.md_magic, G_ELI_MAGIC) != 0)
1086 		return (NULL);
1087 	if (md.md_version > G_ELI_VERSION) {
1088 		printf("geom_eli.ko module is too old to handle %s.\n",
1089 		    pp->name);
1090 		return (NULL);
1091 	}
1092 	if (md.md_provsize != pp->mediasize)
1093 		return (NULL);
1094 	/* Should we attach it on boot? */
1095 	if (!(md.md_flags & G_ELI_FLAG_BOOT))
1096 		return (NULL);
1097 	if (md.md_keys == 0x00) {
1098 		G_ELI_DEBUG(0, "No valid keys on %s.", pp->name);
1099 		return (NULL);
1100 	}
1101 	if (md.md_iterations == -1) {
1102 		/* If there is no passphrase, we try only once. */
1103 		tries = 1;
1104 	} else {
1105 		/* Ask for the passphrase no more than g_eli_tries times. */
1106 		tries = g_eli_tries;
1107 	}
1108 
1109 	for (i = 0; i <= tries; i++) {
1110 		g_eli_crypto_hmac_init(&ctx, NULL, 0);
1111 
1112 		/*
1113 		 * Load all key files.
1114 		 */
1115 		nkeyfiles = g_eli_keyfiles_load(&ctx, pp->name);
1116 
1117 		if (nkeyfiles == 0 && md.md_iterations == -1) {
1118 			/*
1119 			 * No key files and no passphrase, something is
1120 			 * definitely wrong here.
1121 			 * geli(8) doesn't allow for such situation, so assume
1122 			 * that there was really no passphrase and in that case
1123 			 * key files are no properly defined in loader.conf.
1124 			 */
1125 			G_ELI_DEBUG(0,
1126 			    "Found no key files in loader.conf for %s.",
1127 			    pp->name);
1128 			return (NULL);
1129 		}
1130 
1131 		/* Ask for the passphrase if defined. */
1132 		if (md.md_iterations >= 0) {
1133 			/* Try first with cached passphrase. */
1134 			if (i == 0) {
1135 				if (!g_eli_boot_passcache)
1136 					continue;
1137 				memcpy(passphrase, cached_passphrase,
1138 				    sizeof(passphrase));
1139 			} else {
1140 				printf("Enter passphrase for %s: ", pp->name);
1141 				cngets(passphrase, sizeof(passphrase),
1142 				    g_eli_visible_passphrase);
1143 				memcpy(cached_passphrase, passphrase,
1144 				    sizeof(passphrase));
1145 			}
1146 		}
1147 
1148 		/*
1149 		 * Prepare Derived-Key from the user passphrase.
1150 		 */
1151 		if (md.md_iterations == 0) {
1152 			g_eli_crypto_hmac_update(&ctx, md.md_salt,
1153 			    sizeof(md.md_salt));
1154 			g_eli_crypto_hmac_update(&ctx, passphrase,
1155 			    strlen(passphrase));
1156 			bzero(passphrase, sizeof(passphrase));
1157 		} else if (md.md_iterations > 0) {
1158 			u_char dkey[G_ELI_USERKEYLEN];
1159 
1160 			pkcs5v2_genkey(dkey, sizeof(dkey), md.md_salt,
1161 			    sizeof(md.md_salt), passphrase, md.md_iterations);
1162 			bzero(passphrase, sizeof(passphrase));
1163 			g_eli_crypto_hmac_update(&ctx, dkey, sizeof(dkey));
1164 			bzero(dkey, sizeof(dkey));
1165 		}
1166 
1167 		g_eli_crypto_hmac_final(&ctx, key, 0);
1168 
1169 		/*
1170 		 * Decrypt Master-Key.
1171 		 */
1172 		error = g_eli_mkey_decrypt(&md, key, mkey, &nkey);
1173 		bzero(key, sizeof(key));
1174 		if (error == -1) {
1175 			if (i == tries) {
1176 				G_ELI_DEBUG(0,
1177 				    "Wrong key for %s. No tries left.",
1178 				    pp->name);
1179 				g_eli_keyfiles_clear(pp->name);
1180 				return (NULL);
1181 			}
1182 			if (i > 0) {
1183 				G_ELI_DEBUG(0,
1184 				    "Wrong key for %s. Tries left: %u.",
1185 				    pp->name, tries - i);
1186 			}
1187 			/* Try again. */
1188 			continue;
1189 		} else if (error > 0) {
1190 			G_ELI_DEBUG(0,
1191 			    "Cannot decrypt Master Key for %s (error=%d).",
1192 			    pp->name, error);
1193 			g_eli_keyfiles_clear(pp->name);
1194 			return (NULL);
1195 		}
1196 		g_eli_keyfiles_clear(pp->name);
1197 		G_ELI_DEBUG(1, "Using Master Key %u for %s.", nkey, pp->name);
1198 		break;
1199 	}
1200 
1201 	/*
1202 	 * We have correct key, let's attach provider.
1203 	 */
1204 	gp = g_eli_create(NULL, mp, pp, &md, mkey, nkey);
1205 	bzero(mkey, sizeof(mkey));
1206 	bzero(&md, sizeof(md));
1207 	if (gp == NULL) {
1208 		G_ELI_DEBUG(0, "Cannot create device %s%s.", pp->name,
1209 		    G_ELI_SUFFIX);
1210 		return (NULL);
1211 	}
1212 	return (gp);
1213 }
1214 
1215 static void
1216 g_eli_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
1217     struct g_consumer *cp, struct g_provider *pp)
1218 {
1219 	struct g_eli_softc *sc;
1220 
1221 	g_topology_assert();
1222 	sc = gp->softc;
1223 	if (sc == NULL)
1224 		return;
1225 	if (pp != NULL || cp != NULL)
1226 		return;	/* Nothing here. */
1227 
1228 	sbuf_printf(sb, "%s<KeysTotal>%ju</KeysTotal>\n", indent,
1229 	    (uintmax_t)sc->sc_ekeys_total);
1230 	sbuf_printf(sb, "%s<KeysAllocated>%ju</KeysAllocated>\n", indent,
1231 	    (uintmax_t)sc->sc_ekeys_allocated);
1232 	sbuf_printf(sb, "%s<Flags>", indent);
1233 	if (sc->sc_flags == 0)
1234 		sbuf_printf(sb, "NONE");
1235 	else {
1236 		int first = 1;
1237 
1238 #define ADD_FLAG(flag, name)	do {					\
1239 	if (sc->sc_flags & (flag)) {					\
1240 		if (!first)						\
1241 			sbuf_printf(sb, ", ");				\
1242 		else							\
1243 			first = 0;					\
1244 		sbuf_printf(sb, name);					\
1245 	}								\
1246 } while (0)
1247 		ADD_FLAG(G_ELI_FLAG_SUSPEND, "SUSPEND");
1248 		ADD_FLAG(G_ELI_FLAG_SINGLE_KEY, "SINGLE-KEY");
1249 		ADD_FLAG(G_ELI_FLAG_NATIVE_BYTE_ORDER, "NATIVE-BYTE-ORDER");
1250 		ADD_FLAG(G_ELI_FLAG_ONETIME, "ONETIME");
1251 		ADD_FLAG(G_ELI_FLAG_BOOT, "BOOT");
1252 		ADD_FLAG(G_ELI_FLAG_WO_DETACH, "W-DETACH");
1253 		ADD_FLAG(G_ELI_FLAG_RW_DETACH, "RW-DETACH");
1254 		ADD_FLAG(G_ELI_FLAG_AUTH, "AUTH");
1255 		ADD_FLAG(G_ELI_FLAG_WOPEN, "W-OPEN");
1256 		ADD_FLAG(G_ELI_FLAG_DESTROY, "DESTROY");
1257 		ADD_FLAG(G_ELI_FLAG_RO, "READ-ONLY");
1258 #undef  ADD_FLAG
1259 	}
1260 	sbuf_printf(sb, "</Flags>\n");
1261 
1262 	if (!(sc->sc_flags & G_ELI_FLAG_ONETIME)) {
1263 		sbuf_printf(sb, "%s<UsedKey>%u</UsedKey>\n", indent,
1264 		    sc->sc_nkey);
1265 	}
1266 	sbuf_printf(sb, "%s<Version>%u</Version>\n", indent, sc->sc_version);
1267 	sbuf_printf(sb, "%s<Crypto>", indent);
1268 	switch (sc->sc_crypto) {
1269 	case G_ELI_CRYPTO_HW:
1270 		sbuf_printf(sb, "hardware");
1271 		break;
1272 	case G_ELI_CRYPTO_SW:
1273 		sbuf_printf(sb, "software");
1274 		break;
1275 	default:
1276 		sbuf_printf(sb, "UNKNOWN");
1277 		break;
1278 	}
1279 	sbuf_printf(sb, "</Crypto>\n");
1280 	if (sc->sc_flags & G_ELI_FLAG_AUTH) {
1281 		sbuf_printf(sb,
1282 		    "%s<AuthenticationAlgorithm>%s</AuthenticationAlgorithm>\n",
1283 		    indent, g_eli_algo2str(sc->sc_aalgo));
1284 	}
1285 	sbuf_printf(sb, "%s<KeyLength>%u</KeyLength>\n", indent,
1286 	    sc->sc_ekeylen);
1287 	sbuf_printf(sb, "%s<EncryptionAlgorithm>%s</EncryptionAlgorithm>\n",
1288 	    indent, g_eli_algo2str(sc->sc_ealgo));
1289 	sbuf_printf(sb, "%s<State>%s</State>\n", indent,
1290 	    (sc->sc_flags & G_ELI_FLAG_SUSPEND) ? "SUSPENDED" : "ACTIVE");
1291 }
1292 
1293 static void
1294 g_eli_shutdown_pre_sync(void *arg, int howto)
1295 {
1296 	struct g_class *mp;
1297 	struct g_geom *gp, *gp2;
1298 	struct g_provider *pp;
1299 	struct g_eli_softc *sc;
1300 	int error;
1301 
1302 	mp = arg;
1303 	DROP_GIANT();
1304 	g_topology_lock();
1305 	LIST_FOREACH_SAFE(gp, &mp->geom, geom, gp2) {
1306 		sc = gp->softc;
1307 		if (sc == NULL)
1308 			continue;
1309 		pp = LIST_FIRST(&gp->provider);
1310 		KASSERT(pp != NULL, ("No provider? gp=%p (%s)", gp, gp->name));
1311 		if (pp->acr + pp->acw + pp->ace == 0)
1312 			error = g_eli_destroy(sc, TRUE);
1313 		else {
1314 			sc->sc_flags |= G_ELI_FLAG_RW_DETACH;
1315 			gp->access = g_eli_access;
1316 		}
1317 	}
1318 	g_topology_unlock();
1319 	PICKUP_GIANT();
1320 }
1321 
1322 static void
1323 g_eli_init(struct g_class *mp)
1324 {
1325 
1326 	g_eli_pre_sync = EVENTHANDLER_REGISTER(shutdown_pre_sync,
1327 	    g_eli_shutdown_pre_sync, mp, SHUTDOWN_PRI_FIRST);
1328 	if (g_eli_pre_sync == NULL)
1329 		G_ELI_DEBUG(0, "Warning! Cannot register shutdown event.");
1330 }
1331 
1332 static void
1333 g_eli_fini(struct g_class *mp)
1334 {
1335 
1336 	if (g_eli_pre_sync != NULL)
1337 		EVENTHANDLER_DEREGISTER(shutdown_pre_sync, g_eli_pre_sync);
1338 }
1339 
1340 DECLARE_GEOM_CLASS(g_eli_class, g_eli);
1341 MODULE_DEPEND(g_eli, crypto, 1, 1, 1);
1342