xref: /freebsd/sys/geom/eli/g_eli.c (revision 1f4bcc459a76b7aa664f3fd557684cd0ba6da352)
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 int
575 g_eli_read_metadata(struct g_class *mp, struct g_provider *pp,
576     struct g_eli_metadata *md)
577 {
578 	struct g_geom *gp;
579 	struct g_consumer *cp;
580 	u_char *buf = NULL;
581 	int error;
582 
583 	g_topology_assert();
584 
585 	gp = g_new_geomf(mp, "eli:taste");
586 	gp->start = g_eli_start;
587 	gp->access = g_std_access;
588 	/*
589 	 * g_eli_read_metadata() is always called from the event thread.
590 	 * Our geom is created and destroyed in the same event, so there
591 	 * could be no orphan nor spoil event in the meantime.
592 	 */
593 	gp->orphan = g_eli_orphan_spoil_assert;
594 	gp->spoiled = g_eli_orphan_spoil_assert;
595 	cp = g_new_consumer(gp);
596 	error = g_attach(cp, pp);
597 	if (error != 0)
598 		goto end;
599 	error = g_access(cp, 1, 0, 0);
600 	if (error != 0)
601 		goto end;
602 	g_topology_unlock();
603 	buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
604 	    &error);
605 	g_topology_lock();
606 	if (buf == NULL)
607 		goto end;
608 	error = eli_metadata_decode(buf, md);
609 	if (error != 0)
610 		goto end;
611 	/* Metadata was read and decoded successfully. */
612 end:
613 	if (buf != NULL)
614 		g_free(buf);
615 	if (cp->provider != NULL) {
616 		if (cp->acr == 1)
617 			g_access(cp, -1, 0, 0);
618 		g_detach(cp);
619 	}
620 	g_destroy_consumer(cp);
621 	g_destroy_geom(gp);
622 	return (error);
623 }
624 
625 /*
626  * The function is called when we had last close on provider and user requested
627  * to close it when this situation occur.
628  */
629 static void
630 g_eli_last_close(void *arg, int flags __unused)
631 {
632 	struct g_geom *gp;
633 	char gpname[64];
634 	int error;
635 
636 	g_topology_assert();
637 	gp = arg;
638 	strlcpy(gpname, gp->name, sizeof(gpname));
639 	error = g_eli_destroy(gp->softc, TRUE);
640 	KASSERT(error == 0, ("Cannot detach %s on last close (error=%d).",
641 	    gpname, error));
642 	G_ELI_DEBUG(0, "Detached %s on last close.", gpname);
643 }
644 
645 int
646 g_eli_access(struct g_provider *pp, int dr, int dw, int de)
647 {
648 	struct g_eli_softc *sc;
649 	struct g_geom *gp;
650 
651 	gp = pp->geom;
652 	sc = gp->softc;
653 
654 	if (dw > 0) {
655 		if (sc->sc_flags & G_ELI_FLAG_RO) {
656 			/* Deny write attempts. */
657 			return (EROFS);
658 		}
659 		/* Someone is opening us for write, we need to remember that. */
660 		sc->sc_flags |= G_ELI_FLAG_WOPEN;
661 		return (0);
662 	}
663 	/* Is this the last close? */
664 	if (pp->acr + dr > 0 || pp->acw + dw > 0 || pp->ace + de > 0)
665 		return (0);
666 
667 	/*
668 	 * Automatically detach on last close if requested.
669 	 */
670 	if ((sc->sc_flags & G_ELI_FLAG_RW_DETACH) ||
671 	    (sc->sc_flags & G_ELI_FLAG_WOPEN)) {
672 		g_post_event(g_eli_last_close, gp, M_WAITOK, NULL);
673 	}
674 	return (0);
675 }
676 
677 static int
678 g_eli_cpu_is_disabled(int cpu)
679 {
680 #ifdef SMP
681 	return (CPU_ISSET(cpu, &hlt_cpus_mask));
682 #else
683 	return (0);
684 #endif
685 }
686 
687 struct g_geom *
688 g_eli_create(struct gctl_req *req, struct g_class *mp, struct g_provider *bpp,
689     const struct g_eli_metadata *md, const u_char *mkey, int nkey)
690 {
691 	struct g_eli_softc *sc;
692 	struct g_eli_worker *wr;
693 	struct g_geom *gp;
694 	struct g_provider *pp;
695 	struct g_consumer *cp;
696 	u_int i, threads;
697 	int error;
698 
699 	G_ELI_DEBUG(1, "Creating device %s%s.", bpp->name, G_ELI_SUFFIX);
700 
701 	gp = g_new_geomf(mp, "%s%s", bpp->name, G_ELI_SUFFIX);
702 	sc = malloc(sizeof(*sc), M_ELI, M_WAITOK | M_ZERO);
703 	gp->start = g_eli_start;
704 	/*
705 	 * Spoiling can happen even though we have the provider open
706 	 * exclusively, e.g. through media change events.
707 	 */
708 	gp->spoiled = g_eli_orphan;
709 	gp->orphan = g_eli_orphan;
710 	gp->dumpconf = g_eli_dumpconf;
711 	/*
712 	 * If detach-on-last-close feature is not enabled and we don't operate
713 	 * on read-only provider, we can simply use g_std_access().
714 	 */
715 	if (md->md_flags & (G_ELI_FLAG_WO_DETACH | G_ELI_FLAG_RO))
716 		gp->access = g_eli_access;
717 	else
718 		gp->access = g_std_access;
719 
720 	eli_metadata_softc(sc, md, bpp->sectorsize, bpp->mediasize);
721 	sc->sc_nkey = nkey;
722 
723 	gp->softc = sc;
724 	sc->sc_geom = gp;
725 
726 	bioq_init(&sc->sc_queue);
727 	mtx_init(&sc->sc_queue_mtx, "geli:queue", NULL, MTX_DEF);
728 	mtx_init(&sc->sc_ekeys_lock, "geli:ekeys", NULL, MTX_DEF);
729 
730 	pp = NULL;
731 	cp = g_new_consumer(gp);
732 	error = g_attach(cp, bpp);
733 	if (error != 0) {
734 		if (req != NULL) {
735 			gctl_error(req, "Cannot attach to %s (error=%d).",
736 			    bpp->name, error);
737 		} else {
738 			G_ELI_DEBUG(1, "Cannot attach to %s (error=%d).",
739 			    bpp->name, error);
740 		}
741 		goto failed;
742 	}
743 	/*
744 	 * Keep provider open all the time, so we can run critical tasks,
745 	 * like Master Keys deletion, without wondering if we can open
746 	 * provider or not.
747 	 * We don't open provider for writing only when user requested read-only
748 	 * access.
749 	 */
750 	if (sc->sc_flags & G_ELI_FLAG_RO)
751 		error = g_access(cp, 1, 0, 1);
752 	else
753 		error = g_access(cp, 1, 1, 1);
754 	if (error != 0) {
755 		if (req != NULL) {
756 			gctl_error(req, "Cannot access %s (error=%d).",
757 			    bpp->name, error);
758 		} else {
759 			G_ELI_DEBUG(1, "Cannot access %s (error=%d).",
760 			    bpp->name, error);
761 		}
762 		goto failed;
763 	}
764 
765 	/*
766 	 * Remember the keys in our softc structure.
767 	 */
768 	g_eli_mkey_propagate(sc, mkey);
769 
770 	LIST_INIT(&sc->sc_workers);
771 
772 	threads = g_eli_threads;
773 	if (threads == 0)
774 		threads = mp_ncpus;
775 	sc->sc_cpubind = (mp_ncpus > 1 && threads == mp_ncpus);
776 	for (i = 0; i < threads; i++) {
777 		if (g_eli_cpu_is_disabled(i)) {
778 			G_ELI_DEBUG(1, "%s: CPU %u disabled, skipping.",
779 			    bpp->name, i);
780 			continue;
781 		}
782 		wr = malloc(sizeof(*wr), M_ELI, M_WAITOK | M_ZERO);
783 		wr->w_softc = sc;
784 		wr->w_number = i;
785 		wr->w_active = TRUE;
786 
787 		error = g_eli_newsession(wr);
788 		if (error != 0) {
789 			free(wr, M_ELI);
790 			if (req != NULL) {
791 				gctl_error(req, "Cannot set up crypto session "
792 				    "for %s (error=%d).", bpp->name, error);
793 			} else {
794 				G_ELI_DEBUG(1, "Cannot set up crypto session "
795 				    "for %s (error=%d).", bpp->name, error);
796 			}
797 			goto failed;
798 		}
799 
800 		error = kproc_create(g_eli_worker, wr, &wr->w_proc, 0, 0,
801 		    "g_eli[%u] %s", i, bpp->name);
802 		if (error != 0) {
803 			g_eli_freesession(wr);
804 			free(wr, M_ELI);
805 			if (req != NULL) {
806 				gctl_error(req, "Cannot create kernel thread "
807 				    "for %s (error=%d).", bpp->name, error);
808 			} else {
809 				G_ELI_DEBUG(1, "Cannot create kernel thread "
810 				    "for %s (error=%d).", bpp->name, error);
811 			}
812 			goto failed;
813 		}
814 		LIST_INSERT_HEAD(&sc->sc_workers, wr, w_next);
815 	}
816 
817 	/*
818 	 * Create decrypted provider.
819 	 */
820 	pp = g_new_providerf(gp, "%s%s", bpp->name, G_ELI_SUFFIX);
821 	pp->mediasize = sc->sc_mediasize;
822 	pp->sectorsize = sc->sc_sectorsize;
823 
824 	g_error_provider(pp, 0);
825 
826 	G_ELI_DEBUG(0, "Device %s created.", pp->name);
827 	G_ELI_DEBUG(0, "Encryption: %s %u", g_eli_algo2str(sc->sc_ealgo),
828 	    sc->sc_ekeylen);
829 	if (sc->sc_flags & G_ELI_FLAG_AUTH)
830 		G_ELI_DEBUG(0, " Integrity: %s", g_eli_algo2str(sc->sc_aalgo));
831 	G_ELI_DEBUG(0, "    Crypto: %s",
832 	    sc->sc_crypto == G_ELI_CRYPTO_SW ? "software" : "hardware");
833 	return (gp);
834 failed:
835 	mtx_lock(&sc->sc_queue_mtx);
836 	sc->sc_flags |= G_ELI_FLAG_DESTROY;
837 	wakeup(sc);
838 	/*
839 	 * Wait for kernel threads self destruction.
840 	 */
841 	while (!LIST_EMPTY(&sc->sc_workers)) {
842 		msleep(&sc->sc_workers, &sc->sc_queue_mtx, PRIBIO,
843 		    "geli:destroy", 0);
844 	}
845 	mtx_destroy(&sc->sc_queue_mtx);
846 	if (cp->provider != NULL) {
847 		if (cp->acr == 1)
848 			g_access(cp, -1, -1, -1);
849 		g_detach(cp);
850 	}
851 	g_destroy_consumer(cp);
852 	g_destroy_geom(gp);
853 	g_eli_key_destroy(sc);
854 	bzero(sc, sizeof(*sc));
855 	free(sc, M_ELI);
856 	return (NULL);
857 }
858 
859 int
860 g_eli_destroy(struct g_eli_softc *sc, boolean_t force)
861 {
862 	struct g_geom *gp;
863 	struct g_provider *pp;
864 
865 	g_topology_assert();
866 
867 	if (sc == NULL)
868 		return (ENXIO);
869 
870 	gp = sc->sc_geom;
871 	pp = LIST_FIRST(&gp->provider);
872 	if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) {
873 		if (force) {
874 			G_ELI_DEBUG(1, "Device %s is still open, so it "
875 			    "cannot be definitely removed.", pp->name);
876 			sc->sc_flags |= G_ELI_FLAG_RW_DETACH;
877 			gp->access = g_eli_access;
878 			g_wither_provider(pp, ENXIO);
879 			return (EBUSY);
880 		} else {
881 			G_ELI_DEBUG(1,
882 			    "Device %s is still open (r%dw%de%d).", pp->name,
883 			    pp->acr, pp->acw, pp->ace);
884 			return (EBUSY);
885 		}
886 	}
887 
888 	mtx_lock(&sc->sc_queue_mtx);
889 	sc->sc_flags |= G_ELI_FLAG_DESTROY;
890 	wakeup(sc);
891 	while (!LIST_EMPTY(&sc->sc_workers)) {
892 		msleep(&sc->sc_workers, &sc->sc_queue_mtx, PRIBIO,
893 		    "geli:destroy", 0);
894 	}
895 	mtx_destroy(&sc->sc_queue_mtx);
896 	gp->softc = NULL;
897 	g_eli_key_destroy(sc);
898 	bzero(sc, sizeof(*sc));
899 	free(sc, M_ELI);
900 
901 	if (pp == NULL || (pp->acr == 0 && pp->acw == 0 && pp->ace == 0))
902 		G_ELI_DEBUG(0, "Device %s destroyed.", gp->name);
903 	g_wither_geom_close(gp, ENXIO);
904 
905 	return (0);
906 }
907 
908 static int
909 g_eli_destroy_geom(struct gctl_req *req __unused,
910     struct g_class *mp __unused, struct g_geom *gp)
911 {
912 	struct g_eli_softc *sc;
913 
914 	sc = gp->softc;
915 	return (g_eli_destroy(sc, FALSE));
916 }
917 
918 static int
919 g_eli_keyfiles_load(struct hmac_ctx *ctx, const char *provider)
920 {
921 	u_char *keyfile, *data;
922 	char *file, name[64];
923 	size_t size;
924 	int i;
925 
926 	for (i = 0; ; i++) {
927 		snprintf(name, sizeof(name), "%s:geli_keyfile%d", provider, i);
928 		keyfile = preload_search_by_type(name);
929 		if (keyfile == NULL && i == 0) {
930 			/*
931 			 * If there is only one keyfile, allow simpler name.
932 			 */
933 			snprintf(name, sizeof(name), "%s:geli_keyfile", provider);
934 			keyfile = preload_search_by_type(name);
935 		}
936 		if (keyfile == NULL)
937 			return (i);	/* Return number of loaded keyfiles. */
938 		data = preload_fetch_addr(keyfile);
939 		if (data == NULL) {
940 			G_ELI_DEBUG(0, "Cannot find key file data for %s.",
941 			    name);
942 			return (0);
943 		}
944 		size = preload_fetch_size(keyfile);
945 		if (size == 0) {
946 			G_ELI_DEBUG(0, "Cannot find key file size for %s.",
947 			    name);
948 			return (0);
949 		}
950 		file = preload_search_info(keyfile, MODINFO_NAME);
951 		if (file == NULL) {
952 			G_ELI_DEBUG(0, "Cannot find key file name for %s.",
953 			    name);
954 			return (0);
955 		}
956 		G_ELI_DEBUG(1, "Loaded keyfile %s for %s (type: %s).", file,
957 		    provider, name);
958 		g_eli_crypto_hmac_update(ctx, data, size);
959 	}
960 }
961 
962 static void
963 g_eli_keyfiles_clear(const char *provider)
964 {
965 	u_char *keyfile, *data;
966 	char name[64];
967 	size_t size;
968 	int i;
969 
970 	for (i = 0; ; i++) {
971 		snprintf(name, sizeof(name), "%s:geli_keyfile%d", provider, i);
972 		keyfile = preload_search_by_type(name);
973 		if (keyfile == NULL)
974 			return;
975 		data = preload_fetch_addr(keyfile);
976 		size = preload_fetch_size(keyfile);
977 		if (data != NULL && size != 0)
978 			bzero(data, size);
979 	}
980 }
981 
982 /*
983  * Tasting is only made on boot.
984  * We detect providers which should be attached before root is mounted.
985  */
986 static struct g_geom *
987 g_eli_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
988 {
989 	struct g_eli_metadata md;
990 	struct g_geom *gp;
991 	struct hmac_ctx ctx;
992 	char passphrase[256];
993 	u_char key[G_ELI_USERKEYLEN], mkey[G_ELI_DATAIVKEYLEN];
994 	u_int i, nkey, nkeyfiles, tries;
995 	int error;
996 
997 	g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
998 	g_topology_assert();
999 
1000 	if (root_mounted() || g_eli_tries == 0)
1001 		return (NULL);
1002 
1003 	G_ELI_DEBUG(3, "Tasting %s.", pp->name);
1004 
1005 	error = g_eli_read_metadata(mp, pp, &md);
1006 	if (error != 0)
1007 		return (NULL);
1008 	gp = NULL;
1009 
1010 	if (strcmp(md.md_magic, G_ELI_MAGIC) != 0)
1011 		return (NULL);
1012 	if (md.md_version > G_ELI_VERSION) {
1013 		printf("geom_eli.ko module is too old to handle %s.\n",
1014 		    pp->name);
1015 		return (NULL);
1016 	}
1017 	if (md.md_provsize != pp->mediasize)
1018 		return (NULL);
1019 	/* Should we attach it on boot? */
1020 	if (!(md.md_flags & G_ELI_FLAG_BOOT))
1021 		return (NULL);
1022 	if (md.md_keys == 0x00) {
1023 		G_ELI_DEBUG(0, "No valid keys on %s.", pp->name);
1024 		return (NULL);
1025 	}
1026 	if (md.md_iterations == -1) {
1027 		/* If there is no passphrase, we try only once. */
1028 		tries = 1;
1029 	} else {
1030 		/* Ask for the passphrase no more than g_eli_tries times. */
1031 		tries = g_eli_tries;
1032 	}
1033 
1034 	for (i = 0; i <= tries; i++) {
1035 		g_eli_crypto_hmac_init(&ctx, NULL, 0);
1036 
1037 		/*
1038 		 * Load all key files.
1039 		 */
1040 		nkeyfiles = g_eli_keyfiles_load(&ctx, pp->name);
1041 
1042 		if (nkeyfiles == 0 && md.md_iterations == -1) {
1043 			/*
1044 			 * No key files and no passphrase, something is
1045 			 * definitely wrong here.
1046 			 * geli(8) doesn't allow for such situation, so assume
1047 			 * that there was really no passphrase and in that case
1048 			 * key files are no properly defined in loader.conf.
1049 			 */
1050 			G_ELI_DEBUG(0,
1051 			    "Found no key files in loader.conf for %s.",
1052 			    pp->name);
1053 			return (NULL);
1054 		}
1055 
1056 		/* Ask for the passphrase if defined. */
1057 		if (md.md_iterations >= 0) {
1058 			/* Try first with cached passphrase. */
1059 			if (i == 0) {
1060 				if (!g_eli_boot_passcache)
1061 					continue;
1062 				memcpy(passphrase, cached_passphrase,
1063 				    sizeof(passphrase));
1064 			} else {
1065 				printf("Enter passphrase for %s: ", pp->name);
1066 				cngets(passphrase, sizeof(passphrase),
1067 				    g_eli_visible_passphrase);
1068 				memcpy(cached_passphrase, passphrase,
1069 				    sizeof(passphrase));
1070 			}
1071 		}
1072 
1073 		/*
1074 		 * Prepare Derived-Key from the user passphrase.
1075 		 */
1076 		if (md.md_iterations == 0) {
1077 			g_eli_crypto_hmac_update(&ctx, md.md_salt,
1078 			    sizeof(md.md_salt));
1079 			g_eli_crypto_hmac_update(&ctx, passphrase,
1080 			    strlen(passphrase));
1081 			bzero(passphrase, sizeof(passphrase));
1082 		} else if (md.md_iterations > 0) {
1083 			u_char dkey[G_ELI_USERKEYLEN];
1084 
1085 			pkcs5v2_genkey(dkey, sizeof(dkey), md.md_salt,
1086 			    sizeof(md.md_salt), passphrase, md.md_iterations);
1087 			bzero(passphrase, sizeof(passphrase));
1088 			g_eli_crypto_hmac_update(&ctx, dkey, sizeof(dkey));
1089 			bzero(dkey, sizeof(dkey));
1090 		}
1091 
1092 		g_eli_crypto_hmac_final(&ctx, key, 0);
1093 
1094 		/*
1095 		 * Decrypt Master-Key.
1096 		 */
1097 		error = g_eli_mkey_decrypt(&md, key, mkey, &nkey);
1098 		bzero(key, sizeof(key));
1099 		if (error == -1) {
1100 			if (i == tries) {
1101 				G_ELI_DEBUG(0,
1102 				    "Wrong key for %s. No tries left.",
1103 				    pp->name);
1104 				g_eli_keyfiles_clear(pp->name);
1105 				return (NULL);
1106 			}
1107 			if (i > 0) {
1108 				G_ELI_DEBUG(0,
1109 				    "Wrong key for %s. Tries left: %u.",
1110 				    pp->name, tries - i);
1111 			}
1112 			/* Try again. */
1113 			continue;
1114 		} else if (error > 0) {
1115 			G_ELI_DEBUG(0,
1116 			    "Cannot decrypt Master Key for %s (error=%d).",
1117 			    pp->name, error);
1118 			g_eli_keyfiles_clear(pp->name);
1119 			return (NULL);
1120 		}
1121 		g_eli_keyfiles_clear(pp->name);
1122 		G_ELI_DEBUG(1, "Using Master Key %u for %s.", nkey, pp->name);
1123 		break;
1124 	}
1125 
1126 	/*
1127 	 * We have correct key, let's attach provider.
1128 	 */
1129 	gp = g_eli_create(NULL, mp, pp, &md, mkey, nkey);
1130 	bzero(mkey, sizeof(mkey));
1131 	bzero(&md, sizeof(md));
1132 	if (gp == NULL) {
1133 		G_ELI_DEBUG(0, "Cannot create device %s%s.", pp->name,
1134 		    G_ELI_SUFFIX);
1135 		return (NULL);
1136 	}
1137 	return (gp);
1138 }
1139 
1140 static void
1141 g_eli_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
1142     struct g_consumer *cp, struct g_provider *pp)
1143 {
1144 	struct g_eli_softc *sc;
1145 
1146 	g_topology_assert();
1147 	sc = gp->softc;
1148 	if (sc == NULL)
1149 		return;
1150 	if (pp != NULL || cp != NULL)
1151 		return;	/* Nothing here. */
1152 
1153 	sbuf_printf(sb, "%s<KeysTotal>%ju</KeysTotal>\n", indent,
1154 	    (uintmax_t)sc->sc_ekeys_total);
1155 	sbuf_printf(sb, "%s<KeysAllocated>%ju</KeysAllocated>\n", indent,
1156 	    (uintmax_t)sc->sc_ekeys_allocated);
1157 	sbuf_printf(sb, "%s<Flags>", indent);
1158 	if (sc->sc_flags == 0)
1159 		sbuf_printf(sb, "NONE");
1160 	else {
1161 		int first = 1;
1162 
1163 #define ADD_FLAG(flag, name)	do {					\
1164 	if (sc->sc_flags & (flag)) {					\
1165 		if (!first)						\
1166 			sbuf_printf(sb, ", ");				\
1167 		else							\
1168 			first = 0;					\
1169 		sbuf_printf(sb, name);					\
1170 	}								\
1171 } while (0)
1172 		ADD_FLAG(G_ELI_FLAG_SUSPEND, "SUSPEND");
1173 		ADD_FLAG(G_ELI_FLAG_SINGLE_KEY, "SINGLE-KEY");
1174 		ADD_FLAG(G_ELI_FLAG_NATIVE_BYTE_ORDER, "NATIVE-BYTE-ORDER");
1175 		ADD_FLAG(G_ELI_FLAG_ONETIME, "ONETIME");
1176 		ADD_FLAG(G_ELI_FLAG_BOOT, "BOOT");
1177 		ADD_FLAG(G_ELI_FLAG_WO_DETACH, "W-DETACH");
1178 		ADD_FLAG(G_ELI_FLAG_RW_DETACH, "RW-DETACH");
1179 		ADD_FLAG(G_ELI_FLAG_AUTH, "AUTH");
1180 		ADD_FLAG(G_ELI_FLAG_WOPEN, "W-OPEN");
1181 		ADD_FLAG(G_ELI_FLAG_DESTROY, "DESTROY");
1182 		ADD_FLAG(G_ELI_FLAG_RO, "READ-ONLY");
1183 		ADD_FLAG(G_ELI_FLAG_NODELETE, "NODELETE");
1184 #undef  ADD_FLAG
1185 	}
1186 	sbuf_printf(sb, "</Flags>\n");
1187 
1188 	if (!(sc->sc_flags & G_ELI_FLAG_ONETIME)) {
1189 		sbuf_printf(sb, "%s<UsedKey>%u</UsedKey>\n", indent,
1190 		    sc->sc_nkey);
1191 	}
1192 	sbuf_printf(sb, "%s<Version>%u</Version>\n", indent, sc->sc_version);
1193 	sbuf_printf(sb, "%s<Crypto>", indent);
1194 	switch (sc->sc_crypto) {
1195 	case G_ELI_CRYPTO_HW:
1196 		sbuf_printf(sb, "hardware");
1197 		break;
1198 	case G_ELI_CRYPTO_SW:
1199 		sbuf_printf(sb, "software");
1200 		break;
1201 	default:
1202 		sbuf_printf(sb, "UNKNOWN");
1203 		break;
1204 	}
1205 	sbuf_printf(sb, "</Crypto>\n");
1206 	if (sc->sc_flags & G_ELI_FLAG_AUTH) {
1207 		sbuf_printf(sb,
1208 		    "%s<AuthenticationAlgorithm>%s</AuthenticationAlgorithm>\n",
1209 		    indent, g_eli_algo2str(sc->sc_aalgo));
1210 	}
1211 	sbuf_printf(sb, "%s<KeyLength>%u</KeyLength>\n", indent,
1212 	    sc->sc_ekeylen);
1213 	sbuf_printf(sb, "%s<EncryptionAlgorithm>%s</EncryptionAlgorithm>\n",
1214 	    indent, g_eli_algo2str(sc->sc_ealgo));
1215 	sbuf_printf(sb, "%s<State>%s</State>\n", indent,
1216 	    (sc->sc_flags & G_ELI_FLAG_SUSPEND) ? "SUSPENDED" : "ACTIVE");
1217 }
1218 
1219 static void
1220 g_eli_shutdown_pre_sync(void *arg, int howto)
1221 {
1222 	struct g_class *mp;
1223 	struct g_geom *gp, *gp2;
1224 	struct g_provider *pp;
1225 	struct g_eli_softc *sc;
1226 	int error;
1227 
1228 	mp = arg;
1229 	DROP_GIANT();
1230 	g_topology_lock();
1231 	LIST_FOREACH_SAFE(gp, &mp->geom, geom, gp2) {
1232 		sc = gp->softc;
1233 		if (sc == NULL)
1234 			continue;
1235 		pp = LIST_FIRST(&gp->provider);
1236 		KASSERT(pp != NULL, ("No provider? gp=%p (%s)", gp, gp->name));
1237 		if (pp->acr + pp->acw + pp->ace == 0)
1238 			error = g_eli_destroy(sc, TRUE);
1239 		else {
1240 			sc->sc_flags |= G_ELI_FLAG_RW_DETACH;
1241 			gp->access = g_eli_access;
1242 		}
1243 	}
1244 	g_topology_unlock();
1245 	PICKUP_GIANT();
1246 }
1247 
1248 static void
1249 g_eli_init(struct g_class *mp)
1250 {
1251 
1252 	g_eli_pre_sync = EVENTHANDLER_REGISTER(shutdown_pre_sync,
1253 	    g_eli_shutdown_pre_sync, mp, SHUTDOWN_PRI_FIRST);
1254 	if (g_eli_pre_sync == NULL)
1255 		G_ELI_DEBUG(0, "Warning! Cannot register shutdown event.");
1256 }
1257 
1258 static void
1259 g_eli_fini(struct g_class *mp)
1260 {
1261 
1262 	if (g_eli_pre_sync != NULL)
1263 		EVENTHANDLER_DEREGISTER(shutdown_pre_sync, g_eli_pre_sync);
1264 }
1265 
1266 DECLARE_GEOM_CLASS(g_eli_class, g_eli);
1267 MODULE_DEPEND(g_eli, crypto, 1, 1, 1);
1268