xref: /freebsd/sys/geom/eli/g_eli.c (revision c563bbe1a956feb4c04981f379d80d297212a006)
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 	case BIO_ZONE:
313 		break;
314 	case BIO_DELETE:
315 		/*
316 		 * If the user hasn't set the NODELETE flag, we just pass
317 		 * it down the stack and let the layers beneath us do (or
318 		 * not) whatever they do with it.  If they have, we
319 		 * reject it.  A possible extension would be an
320 		 * additional flag to take it as a hint to shred the data
321 		 * with [multiple?] overwrites.
322 		 */
323 		if (!(sc->sc_flags & G_ELI_FLAG_NODELETE))
324 			break;
325 	default:
326 		g_io_deliver(bp, EOPNOTSUPP);
327 		return;
328 	}
329 	cbp = g_clone_bio(bp);
330 	if (cbp == NULL) {
331 		g_io_deliver(bp, ENOMEM);
332 		return;
333 	}
334 	bp->bio_driver1 = cbp;
335 	bp->bio_pflags = G_ELI_NEW_BIO;
336 	switch (bp->bio_cmd) {
337 	case BIO_READ:
338 		if (!(sc->sc_flags & G_ELI_FLAG_AUTH)) {
339 			g_eli_crypto_read(sc, bp, 0);
340 			break;
341 		}
342 		/* FALLTHROUGH */
343 	case BIO_WRITE:
344 		mtx_lock(&sc->sc_queue_mtx);
345 		bioq_insert_tail(&sc->sc_queue, bp);
346 		mtx_unlock(&sc->sc_queue_mtx);
347 		wakeup(sc);
348 		break;
349 	case BIO_GETATTR:
350 	case BIO_FLUSH:
351 	case BIO_DELETE:
352 	case BIO_ZONE:
353 		cbp->bio_done = g_std_done;
354 		cp = LIST_FIRST(&sc->sc_geom->consumer);
355 		cbp->bio_to = cp->provider;
356 		G_ELI_LOGREQ(2, cbp, "Sending request.");
357 		g_io_request(cbp, cp);
358 		break;
359 	}
360 }
361 
362 static int
363 g_eli_newsession(struct g_eli_worker *wr)
364 {
365 	struct g_eli_softc *sc;
366 	struct cryptoini crie, cria;
367 	int error;
368 
369 	sc = wr->w_softc;
370 
371 	bzero(&crie, sizeof(crie));
372 	crie.cri_alg = sc->sc_ealgo;
373 	crie.cri_klen = sc->sc_ekeylen;
374 	if (sc->sc_ealgo == CRYPTO_AES_XTS)
375 		crie.cri_klen <<= 1;
376 	if ((sc->sc_flags & G_ELI_FLAG_FIRST_KEY) != 0) {
377 		crie.cri_key = g_eli_key_hold(sc, 0,
378 		    LIST_FIRST(&sc->sc_geom->consumer)->provider->sectorsize);
379 	} else {
380 		crie.cri_key = sc->sc_ekey;
381 	}
382 	if (sc->sc_flags & G_ELI_FLAG_AUTH) {
383 		bzero(&cria, sizeof(cria));
384 		cria.cri_alg = sc->sc_aalgo;
385 		cria.cri_klen = sc->sc_akeylen;
386 		cria.cri_key = sc->sc_akey;
387 		crie.cri_next = &cria;
388 	}
389 
390 	switch (sc->sc_crypto) {
391 	case G_ELI_CRYPTO_SW:
392 		error = crypto_newsession(&wr->w_sid, &crie,
393 		    CRYPTOCAP_F_SOFTWARE);
394 		break;
395 	case G_ELI_CRYPTO_HW:
396 		error = crypto_newsession(&wr->w_sid, &crie,
397 		    CRYPTOCAP_F_HARDWARE);
398 		break;
399 	case G_ELI_CRYPTO_UNKNOWN:
400 		error = crypto_newsession(&wr->w_sid, &crie,
401 		    CRYPTOCAP_F_HARDWARE);
402 		if (error == 0) {
403 			mtx_lock(&sc->sc_queue_mtx);
404 			if (sc->sc_crypto == G_ELI_CRYPTO_UNKNOWN)
405 				sc->sc_crypto = G_ELI_CRYPTO_HW;
406 			mtx_unlock(&sc->sc_queue_mtx);
407 		} else {
408 			error = crypto_newsession(&wr->w_sid, &crie,
409 			    CRYPTOCAP_F_SOFTWARE);
410 			mtx_lock(&sc->sc_queue_mtx);
411 			if (sc->sc_crypto == G_ELI_CRYPTO_UNKNOWN)
412 				sc->sc_crypto = G_ELI_CRYPTO_SW;
413 			mtx_unlock(&sc->sc_queue_mtx);
414 		}
415 		break;
416 	default:
417 		panic("%s: invalid condition", __func__);
418 	}
419 
420 	if ((sc->sc_flags & G_ELI_FLAG_FIRST_KEY) != 0)
421 		g_eli_key_drop(sc, crie.cri_key);
422 
423 	return (error);
424 }
425 
426 static void
427 g_eli_freesession(struct g_eli_worker *wr)
428 {
429 
430 	crypto_freesession(wr->w_sid);
431 }
432 
433 static void
434 g_eli_cancel(struct g_eli_softc *sc)
435 {
436 	struct bio *bp;
437 
438 	mtx_assert(&sc->sc_queue_mtx, MA_OWNED);
439 
440 	while ((bp = bioq_takefirst(&sc->sc_queue)) != NULL) {
441 		KASSERT(bp->bio_pflags == G_ELI_NEW_BIO,
442 		    ("Not new bio when canceling (bp=%p).", bp));
443 		g_io_deliver(bp, ENXIO);
444 	}
445 }
446 
447 static struct bio *
448 g_eli_takefirst(struct g_eli_softc *sc)
449 {
450 	struct bio *bp;
451 
452 	mtx_assert(&sc->sc_queue_mtx, MA_OWNED);
453 
454 	if (!(sc->sc_flags & G_ELI_FLAG_SUSPEND))
455 		return (bioq_takefirst(&sc->sc_queue));
456 	/*
457 	 * Device suspended, so we skip new I/O requests.
458 	 */
459 	TAILQ_FOREACH(bp, &sc->sc_queue.queue, bio_queue) {
460 		if (bp->bio_pflags != G_ELI_NEW_BIO)
461 			break;
462 	}
463 	if (bp != NULL)
464 		bioq_remove(&sc->sc_queue, bp);
465 	return (bp);
466 }
467 
468 /*
469  * This is the main function for kernel worker thread when we don't have
470  * hardware acceleration and we have to do cryptography in software.
471  * Dedicated thread is needed, so we don't slow down g_up/g_down GEOM
472  * threads with crypto work.
473  */
474 static void
475 g_eli_worker(void *arg)
476 {
477 	struct g_eli_softc *sc;
478 	struct g_eli_worker *wr;
479 	struct bio *bp;
480 	int error;
481 
482 	wr = arg;
483 	sc = wr->w_softc;
484 #ifdef EARLY_AP_STARTUP
485 	MPASS(!sc->sc_cpubind || smp_started);
486 #elif defined(SMP)
487 	/* Before sched_bind() to a CPU, wait for all CPUs to go on-line. */
488 	if (sc->sc_cpubind) {
489 		while (!smp_started)
490 			tsleep(wr, 0, "geli:smp", hz / 4);
491 	}
492 #endif
493 	thread_lock(curthread);
494 	sched_prio(curthread, PUSER);
495 	if (sc->sc_cpubind)
496 		sched_bind(curthread, wr->w_number % mp_ncpus);
497 	thread_unlock(curthread);
498 
499 	G_ELI_DEBUG(1, "Thread %s started.", curthread->td_proc->p_comm);
500 
501 	for (;;) {
502 		mtx_lock(&sc->sc_queue_mtx);
503 again:
504 		bp = g_eli_takefirst(sc);
505 		if (bp == NULL) {
506 			if (sc->sc_flags & G_ELI_FLAG_DESTROY) {
507 				g_eli_cancel(sc);
508 				LIST_REMOVE(wr, w_next);
509 				g_eli_freesession(wr);
510 				free(wr, M_ELI);
511 				G_ELI_DEBUG(1, "Thread %s exiting.",
512 				    curthread->td_proc->p_comm);
513 				wakeup(&sc->sc_workers);
514 				mtx_unlock(&sc->sc_queue_mtx);
515 				kproc_exit(0);
516 			}
517 			while (sc->sc_flags & G_ELI_FLAG_SUSPEND) {
518 				if (sc->sc_inflight > 0) {
519 					G_ELI_DEBUG(0, "inflight=%d",
520 					    sc->sc_inflight);
521 					/*
522 					 * We still have inflight BIOs, so
523 					 * sleep and retry.
524 					 */
525 					msleep(sc, &sc->sc_queue_mtx, PRIBIO,
526 					    "geli:inf", hz / 5);
527 					goto again;
528 				}
529 				/*
530 				 * Suspend requested, mark the worker as
531 				 * suspended and go to sleep.
532 				 */
533 				if (wr->w_active) {
534 					g_eli_freesession(wr);
535 					wr->w_active = FALSE;
536 				}
537 				wakeup(&sc->sc_workers);
538 				msleep(sc, &sc->sc_queue_mtx, PRIBIO,
539 				    "geli:suspend", 0);
540 				if (!wr->w_active &&
541 				    !(sc->sc_flags & G_ELI_FLAG_SUSPEND)) {
542 					error = g_eli_newsession(wr);
543 					KASSERT(error == 0,
544 					    ("g_eli_newsession() failed on resume (error=%d)",
545 					    error));
546 					wr->w_active = TRUE;
547 				}
548 				goto again;
549 			}
550 			msleep(sc, &sc->sc_queue_mtx, PDROP, "geli:w", 0);
551 			continue;
552 		}
553 		if (bp->bio_pflags == G_ELI_NEW_BIO)
554 			atomic_add_int(&sc->sc_inflight, 1);
555 		mtx_unlock(&sc->sc_queue_mtx);
556 		if (bp->bio_pflags == G_ELI_NEW_BIO) {
557 			bp->bio_pflags = 0;
558 			if (sc->sc_flags & G_ELI_FLAG_AUTH) {
559 				if (bp->bio_cmd == BIO_READ)
560 					g_eli_auth_read(sc, bp);
561 				else
562 					g_eli_auth_run(wr, bp);
563 			} else {
564 				if (bp->bio_cmd == BIO_READ)
565 					g_eli_crypto_read(sc, bp, 1);
566 				else
567 					g_eli_crypto_run(wr, bp);
568 			}
569 		} else {
570 			if (sc->sc_flags & G_ELI_FLAG_AUTH)
571 				g_eli_auth_run(wr, bp);
572 			else
573 				g_eli_crypto_run(wr, bp);
574 		}
575 	}
576 }
577 
578 int
579 g_eli_read_metadata(struct g_class *mp, struct g_provider *pp,
580     struct g_eli_metadata *md)
581 {
582 	struct g_geom *gp;
583 	struct g_consumer *cp;
584 	u_char *buf = NULL;
585 	int error;
586 
587 	g_topology_assert();
588 
589 	gp = g_new_geomf(mp, "eli:taste");
590 	gp->start = g_eli_start;
591 	gp->access = g_std_access;
592 	/*
593 	 * g_eli_read_metadata() is always called from the event thread.
594 	 * Our geom is created and destroyed in the same event, so there
595 	 * could be no orphan nor spoil event in the meantime.
596 	 */
597 	gp->orphan = g_eli_orphan_spoil_assert;
598 	gp->spoiled = g_eli_orphan_spoil_assert;
599 	cp = g_new_consumer(gp);
600 	error = g_attach(cp, pp);
601 	if (error != 0)
602 		goto end;
603 	error = g_access(cp, 1, 0, 0);
604 	if (error != 0)
605 		goto end;
606 	g_topology_unlock();
607 	buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
608 	    &error);
609 	g_topology_lock();
610 	if (buf == NULL)
611 		goto end;
612 	error = eli_metadata_decode(buf, md);
613 	if (error != 0)
614 		goto end;
615 	/* Metadata was read and decoded successfully. */
616 end:
617 	if (buf != NULL)
618 		g_free(buf);
619 	if (cp->provider != NULL) {
620 		if (cp->acr == 1)
621 			g_access(cp, -1, 0, 0);
622 		g_detach(cp);
623 	}
624 	g_destroy_consumer(cp);
625 	g_destroy_geom(gp);
626 	return (error);
627 }
628 
629 /*
630  * The function is called when we had last close on provider and user requested
631  * to close it when this situation occur.
632  */
633 static void
634 g_eli_last_close(void *arg, int flags __unused)
635 {
636 	struct g_geom *gp;
637 	char gpname[64];
638 	int error;
639 
640 	g_topology_assert();
641 	gp = arg;
642 	strlcpy(gpname, gp->name, sizeof(gpname));
643 	error = g_eli_destroy(gp->softc, TRUE);
644 	KASSERT(error == 0, ("Cannot detach %s on last close (error=%d).",
645 	    gpname, error));
646 	G_ELI_DEBUG(0, "Detached %s on last close.", gpname);
647 }
648 
649 int
650 g_eli_access(struct g_provider *pp, int dr, int dw, int de)
651 {
652 	struct g_eli_softc *sc;
653 	struct g_geom *gp;
654 
655 	gp = pp->geom;
656 	sc = gp->softc;
657 
658 	if (dw > 0) {
659 		if (sc->sc_flags & G_ELI_FLAG_RO) {
660 			/* Deny write attempts. */
661 			return (EROFS);
662 		}
663 		/* Someone is opening us for write, we need to remember that. */
664 		sc->sc_flags |= G_ELI_FLAG_WOPEN;
665 		return (0);
666 	}
667 	/* Is this the last close? */
668 	if (pp->acr + dr > 0 || pp->acw + dw > 0 || pp->ace + de > 0)
669 		return (0);
670 
671 	/*
672 	 * Automatically detach on last close if requested.
673 	 */
674 	if ((sc->sc_flags & G_ELI_FLAG_RW_DETACH) ||
675 	    (sc->sc_flags & G_ELI_FLAG_WOPEN)) {
676 		g_post_event(g_eli_last_close, gp, M_WAITOK, NULL);
677 	}
678 	return (0);
679 }
680 
681 static int
682 g_eli_cpu_is_disabled(int cpu)
683 {
684 #ifdef SMP
685 	return (CPU_ISSET(cpu, &hlt_cpus_mask));
686 #else
687 	return (0);
688 #endif
689 }
690 
691 struct g_geom *
692 g_eli_create(struct gctl_req *req, struct g_class *mp, struct g_provider *bpp,
693     const struct g_eli_metadata *md, const u_char *mkey, int nkey)
694 {
695 	struct g_eli_softc *sc;
696 	struct g_eli_worker *wr;
697 	struct g_geom *gp;
698 	struct g_provider *pp;
699 	struct g_consumer *cp;
700 	u_int i, threads;
701 	int error;
702 
703 	G_ELI_DEBUG(1, "Creating device %s%s.", bpp->name, G_ELI_SUFFIX);
704 
705 	gp = g_new_geomf(mp, "%s%s", bpp->name, G_ELI_SUFFIX);
706 	sc = malloc(sizeof(*sc), M_ELI, M_WAITOK | M_ZERO);
707 	gp->start = g_eli_start;
708 	/*
709 	 * Spoiling can happen even though we have the provider open
710 	 * exclusively, e.g. through media change events.
711 	 */
712 	gp->spoiled = g_eli_orphan;
713 	gp->orphan = g_eli_orphan;
714 	gp->dumpconf = g_eli_dumpconf;
715 	/*
716 	 * If detach-on-last-close feature is not enabled and we don't operate
717 	 * on read-only provider, we can simply use g_std_access().
718 	 */
719 	if (md->md_flags & (G_ELI_FLAG_WO_DETACH | G_ELI_FLAG_RO))
720 		gp->access = g_eli_access;
721 	else
722 		gp->access = g_std_access;
723 
724 	eli_metadata_softc(sc, md, bpp->sectorsize, bpp->mediasize);
725 	sc->sc_nkey = nkey;
726 
727 	gp->softc = sc;
728 	sc->sc_geom = gp;
729 
730 	bioq_init(&sc->sc_queue);
731 	mtx_init(&sc->sc_queue_mtx, "geli:queue", NULL, MTX_DEF);
732 	mtx_init(&sc->sc_ekeys_lock, "geli:ekeys", NULL, MTX_DEF);
733 
734 	pp = NULL;
735 	cp = g_new_consumer(gp);
736 	error = g_attach(cp, bpp);
737 	if (error != 0) {
738 		if (req != NULL) {
739 			gctl_error(req, "Cannot attach to %s (error=%d).",
740 			    bpp->name, error);
741 		} else {
742 			G_ELI_DEBUG(1, "Cannot attach to %s (error=%d).",
743 			    bpp->name, error);
744 		}
745 		goto failed;
746 	}
747 	/*
748 	 * Keep provider open all the time, so we can run critical tasks,
749 	 * like Master Keys deletion, without wondering if we can open
750 	 * provider or not.
751 	 * We don't open provider for writing only when user requested read-only
752 	 * access.
753 	 */
754 	if (sc->sc_flags & G_ELI_FLAG_RO)
755 		error = g_access(cp, 1, 0, 1);
756 	else
757 		error = g_access(cp, 1, 1, 1);
758 	if (error != 0) {
759 		if (req != NULL) {
760 			gctl_error(req, "Cannot access %s (error=%d).",
761 			    bpp->name, error);
762 		} else {
763 			G_ELI_DEBUG(1, "Cannot access %s (error=%d).",
764 			    bpp->name, error);
765 		}
766 		goto failed;
767 	}
768 
769 	/*
770 	 * Remember the keys in our softc structure.
771 	 */
772 	g_eli_mkey_propagate(sc, mkey);
773 
774 	LIST_INIT(&sc->sc_workers);
775 
776 	threads = g_eli_threads;
777 	if (threads == 0)
778 		threads = mp_ncpus;
779 	sc->sc_cpubind = (mp_ncpus > 1 && threads == mp_ncpus);
780 	for (i = 0; i < threads; i++) {
781 		if (g_eli_cpu_is_disabled(i)) {
782 			G_ELI_DEBUG(1, "%s: CPU %u disabled, skipping.",
783 			    bpp->name, i);
784 			continue;
785 		}
786 		wr = malloc(sizeof(*wr), M_ELI, M_WAITOK | M_ZERO);
787 		wr->w_softc = sc;
788 		wr->w_number = i;
789 		wr->w_active = TRUE;
790 
791 		error = g_eli_newsession(wr);
792 		if (error != 0) {
793 			free(wr, M_ELI);
794 			if (req != NULL) {
795 				gctl_error(req, "Cannot set up crypto session "
796 				    "for %s (error=%d).", bpp->name, error);
797 			} else {
798 				G_ELI_DEBUG(1, "Cannot set up crypto session "
799 				    "for %s (error=%d).", bpp->name, error);
800 			}
801 			goto failed;
802 		}
803 
804 		error = kproc_create(g_eli_worker, wr, &wr->w_proc, 0, 0,
805 		    "g_eli[%u] %s", i, bpp->name);
806 		if (error != 0) {
807 			g_eli_freesession(wr);
808 			free(wr, M_ELI);
809 			if (req != NULL) {
810 				gctl_error(req, "Cannot create kernel thread "
811 				    "for %s (error=%d).", bpp->name, error);
812 			} else {
813 				G_ELI_DEBUG(1, "Cannot create kernel thread "
814 				    "for %s (error=%d).", bpp->name, error);
815 			}
816 			goto failed;
817 		}
818 		LIST_INSERT_HEAD(&sc->sc_workers, wr, w_next);
819 	}
820 
821 	/*
822 	 * Create decrypted provider.
823 	 */
824 	pp = g_new_providerf(gp, "%s%s", bpp->name, G_ELI_SUFFIX);
825 	pp->mediasize = sc->sc_mediasize;
826 	pp->sectorsize = sc->sc_sectorsize;
827 
828 	g_error_provider(pp, 0);
829 
830 	G_ELI_DEBUG(0, "Device %s created.", pp->name);
831 	G_ELI_DEBUG(0, "Encryption: %s %u", g_eli_algo2str(sc->sc_ealgo),
832 	    sc->sc_ekeylen);
833 	if (sc->sc_flags & G_ELI_FLAG_AUTH)
834 		G_ELI_DEBUG(0, " Integrity: %s", g_eli_algo2str(sc->sc_aalgo));
835 	G_ELI_DEBUG(0, "    Crypto: %s",
836 	    sc->sc_crypto == G_ELI_CRYPTO_SW ? "software" : "hardware");
837 	return (gp);
838 failed:
839 	mtx_lock(&sc->sc_queue_mtx);
840 	sc->sc_flags |= G_ELI_FLAG_DESTROY;
841 	wakeup(sc);
842 	/*
843 	 * Wait for kernel threads self destruction.
844 	 */
845 	while (!LIST_EMPTY(&sc->sc_workers)) {
846 		msleep(&sc->sc_workers, &sc->sc_queue_mtx, PRIBIO,
847 		    "geli:destroy", 0);
848 	}
849 	mtx_destroy(&sc->sc_queue_mtx);
850 	if (cp->provider != NULL) {
851 		if (cp->acr == 1)
852 			g_access(cp, -1, -1, -1);
853 		g_detach(cp);
854 	}
855 	g_destroy_consumer(cp);
856 	g_destroy_geom(gp);
857 	g_eli_key_destroy(sc);
858 	bzero(sc, sizeof(*sc));
859 	free(sc, M_ELI);
860 	return (NULL);
861 }
862 
863 int
864 g_eli_destroy(struct g_eli_softc *sc, boolean_t force)
865 {
866 	struct g_geom *gp;
867 	struct g_provider *pp;
868 
869 	g_topology_assert();
870 
871 	if (sc == NULL)
872 		return (ENXIO);
873 
874 	gp = sc->sc_geom;
875 	pp = LIST_FIRST(&gp->provider);
876 	if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) {
877 		if (force) {
878 			G_ELI_DEBUG(1, "Device %s is still open, so it "
879 			    "cannot be definitely removed.", pp->name);
880 			sc->sc_flags |= G_ELI_FLAG_RW_DETACH;
881 			gp->access = g_eli_access;
882 			g_wither_provider(pp, ENXIO);
883 			return (EBUSY);
884 		} else {
885 			G_ELI_DEBUG(1,
886 			    "Device %s is still open (r%dw%de%d).", pp->name,
887 			    pp->acr, pp->acw, pp->ace);
888 			return (EBUSY);
889 		}
890 	}
891 
892 	mtx_lock(&sc->sc_queue_mtx);
893 	sc->sc_flags |= G_ELI_FLAG_DESTROY;
894 	wakeup(sc);
895 	while (!LIST_EMPTY(&sc->sc_workers)) {
896 		msleep(&sc->sc_workers, &sc->sc_queue_mtx, PRIBIO,
897 		    "geli:destroy", 0);
898 	}
899 	mtx_destroy(&sc->sc_queue_mtx);
900 	gp->softc = NULL;
901 	g_eli_key_destroy(sc);
902 	bzero(sc, sizeof(*sc));
903 	free(sc, M_ELI);
904 
905 	if (pp == NULL || (pp->acr == 0 && pp->acw == 0 && pp->ace == 0))
906 		G_ELI_DEBUG(0, "Device %s destroyed.", gp->name);
907 	g_wither_geom_close(gp, ENXIO);
908 
909 	return (0);
910 }
911 
912 static int
913 g_eli_destroy_geom(struct gctl_req *req __unused,
914     struct g_class *mp __unused, struct g_geom *gp)
915 {
916 	struct g_eli_softc *sc;
917 
918 	sc = gp->softc;
919 	return (g_eli_destroy(sc, FALSE));
920 }
921 
922 static int
923 g_eli_keyfiles_load(struct hmac_ctx *ctx, const char *provider)
924 {
925 	u_char *keyfile, *data;
926 	char *file, name[64];
927 	size_t size;
928 	int i;
929 
930 	for (i = 0; ; i++) {
931 		snprintf(name, sizeof(name), "%s:geli_keyfile%d", provider, i);
932 		keyfile = preload_search_by_type(name);
933 		if (keyfile == NULL && i == 0) {
934 			/*
935 			 * If there is only one keyfile, allow simpler name.
936 			 */
937 			snprintf(name, sizeof(name), "%s:geli_keyfile", provider);
938 			keyfile = preload_search_by_type(name);
939 		}
940 		if (keyfile == NULL)
941 			return (i);	/* Return number of loaded keyfiles. */
942 		data = preload_fetch_addr(keyfile);
943 		if (data == NULL) {
944 			G_ELI_DEBUG(0, "Cannot find key file data for %s.",
945 			    name);
946 			return (0);
947 		}
948 		size = preload_fetch_size(keyfile);
949 		if (size == 0) {
950 			G_ELI_DEBUG(0, "Cannot find key file size for %s.",
951 			    name);
952 			return (0);
953 		}
954 		file = preload_search_info(keyfile, MODINFO_NAME);
955 		if (file == NULL) {
956 			G_ELI_DEBUG(0, "Cannot find key file name for %s.",
957 			    name);
958 			return (0);
959 		}
960 		G_ELI_DEBUG(1, "Loaded keyfile %s for %s (type: %s).", file,
961 		    provider, name);
962 		g_eli_crypto_hmac_update(ctx, data, size);
963 	}
964 }
965 
966 static void
967 g_eli_keyfiles_clear(const char *provider)
968 {
969 	u_char *keyfile, *data;
970 	char name[64];
971 	size_t size;
972 	int i;
973 
974 	for (i = 0; ; i++) {
975 		snprintf(name, sizeof(name), "%s:geli_keyfile%d", provider, i);
976 		keyfile = preload_search_by_type(name);
977 		if (keyfile == NULL)
978 			return;
979 		data = preload_fetch_addr(keyfile);
980 		size = preload_fetch_size(keyfile);
981 		if (data != NULL && size != 0)
982 			bzero(data, size);
983 	}
984 }
985 
986 /*
987  * Tasting is only made on boot.
988  * We detect providers which should be attached before root is mounted.
989  */
990 static struct g_geom *
991 g_eli_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
992 {
993 	struct g_eli_metadata md;
994 	struct g_geom *gp;
995 	struct hmac_ctx ctx;
996 	char passphrase[256];
997 	u_char key[G_ELI_USERKEYLEN], mkey[G_ELI_DATAIVKEYLEN];
998 	u_int i, nkey, nkeyfiles, tries;
999 	int error;
1000 
1001 	g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
1002 	g_topology_assert();
1003 
1004 	if (root_mounted() || g_eli_tries == 0)
1005 		return (NULL);
1006 
1007 	G_ELI_DEBUG(3, "Tasting %s.", pp->name);
1008 
1009 	error = g_eli_read_metadata(mp, pp, &md);
1010 	if (error != 0)
1011 		return (NULL);
1012 	gp = NULL;
1013 
1014 	if (strcmp(md.md_magic, G_ELI_MAGIC) != 0)
1015 		return (NULL);
1016 	if (md.md_version > G_ELI_VERSION) {
1017 		printf("geom_eli.ko module is too old to handle %s.\n",
1018 		    pp->name);
1019 		return (NULL);
1020 	}
1021 	if (md.md_provsize != pp->mediasize)
1022 		return (NULL);
1023 	/* Should we attach it on boot? */
1024 	if (!(md.md_flags & G_ELI_FLAG_BOOT))
1025 		return (NULL);
1026 	if (md.md_keys == 0x00) {
1027 		G_ELI_DEBUG(0, "No valid keys on %s.", pp->name);
1028 		return (NULL);
1029 	}
1030 	if (md.md_iterations == -1) {
1031 		/* If there is no passphrase, we try only once. */
1032 		tries = 1;
1033 	} else {
1034 		/* Ask for the passphrase no more than g_eli_tries times. */
1035 		tries = g_eli_tries;
1036 	}
1037 
1038 	for (i = 0; i <= tries; i++) {
1039 		g_eli_crypto_hmac_init(&ctx, NULL, 0);
1040 
1041 		/*
1042 		 * Load all key files.
1043 		 */
1044 		nkeyfiles = g_eli_keyfiles_load(&ctx, pp->name);
1045 
1046 		if (nkeyfiles == 0 && md.md_iterations == -1) {
1047 			/*
1048 			 * No key files and no passphrase, something is
1049 			 * definitely wrong here.
1050 			 * geli(8) doesn't allow for such situation, so assume
1051 			 * that there was really no passphrase and in that case
1052 			 * key files are no properly defined in loader.conf.
1053 			 */
1054 			G_ELI_DEBUG(0,
1055 			    "Found no key files in loader.conf for %s.",
1056 			    pp->name);
1057 			return (NULL);
1058 		}
1059 
1060 		/* Ask for the passphrase if defined. */
1061 		if (md.md_iterations >= 0) {
1062 			/* Try first with cached passphrase. */
1063 			if (i == 0) {
1064 				if (!g_eli_boot_passcache)
1065 					continue;
1066 				memcpy(passphrase, cached_passphrase,
1067 				    sizeof(passphrase));
1068 			} else {
1069 				printf("Enter passphrase for %s: ", pp->name);
1070 				cngets(passphrase, sizeof(passphrase),
1071 				    g_eli_visible_passphrase);
1072 				memcpy(cached_passphrase, passphrase,
1073 				    sizeof(passphrase));
1074 			}
1075 		}
1076 
1077 		/*
1078 		 * Prepare Derived-Key from the user passphrase.
1079 		 */
1080 		if (md.md_iterations == 0) {
1081 			g_eli_crypto_hmac_update(&ctx, md.md_salt,
1082 			    sizeof(md.md_salt));
1083 			g_eli_crypto_hmac_update(&ctx, passphrase,
1084 			    strlen(passphrase));
1085 			bzero(passphrase, sizeof(passphrase));
1086 		} else if (md.md_iterations > 0) {
1087 			u_char dkey[G_ELI_USERKEYLEN];
1088 
1089 			pkcs5v2_genkey(dkey, sizeof(dkey), md.md_salt,
1090 			    sizeof(md.md_salt), passphrase, md.md_iterations);
1091 			bzero(passphrase, sizeof(passphrase));
1092 			g_eli_crypto_hmac_update(&ctx, dkey, sizeof(dkey));
1093 			bzero(dkey, sizeof(dkey));
1094 		}
1095 
1096 		g_eli_crypto_hmac_final(&ctx, key, 0);
1097 
1098 		/*
1099 		 * Decrypt Master-Key.
1100 		 */
1101 		error = g_eli_mkey_decrypt(&md, key, mkey, &nkey);
1102 		bzero(key, sizeof(key));
1103 		if (error == -1) {
1104 			if (i == tries) {
1105 				G_ELI_DEBUG(0,
1106 				    "Wrong key for %s. No tries left.",
1107 				    pp->name);
1108 				g_eli_keyfiles_clear(pp->name);
1109 				return (NULL);
1110 			}
1111 			if (i > 0) {
1112 				G_ELI_DEBUG(0,
1113 				    "Wrong key for %s. Tries left: %u.",
1114 				    pp->name, tries - i);
1115 			}
1116 			/* Try again. */
1117 			continue;
1118 		} else if (error > 0) {
1119 			G_ELI_DEBUG(0,
1120 			    "Cannot decrypt Master Key for %s (error=%d).",
1121 			    pp->name, error);
1122 			g_eli_keyfiles_clear(pp->name);
1123 			return (NULL);
1124 		}
1125 		g_eli_keyfiles_clear(pp->name);
1126 		G_ELI_DEBUG(1, "Using Master Key %u for %s.", nkey, pp->name);
1127 		break;
1128 	}
1129 
1130 	/*
1131 	 * We have correct key, let's attach provider.
1132 	 */
1133 	gp = g_eli_create(NULL, mp, pp, &md, mkey, nkey);
1134 	bzero(mkey, sizeof(mkey));
1135 	bzero(&md, sizeof(md));
1136 	if (gp == NULL) {
1137 		G_ELI_DEBUG(0, "Cannot create device %s%s.", pp->name,
1138 		    G_ELI_SUFFIX);
1139 		return (NULL);
1140 	}
1141 	return (gp);
1142 }
1143 
1144 static void
1145 g_eli_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
1146     struct g_consumer *cp, struct g_provider *pp)
1147 {
1148 	struct g_eli_softc *sc;
1149 
1150 	g_topology_assert();
1151 	sc = gp->softc;
1152 	if (sc == NULL)
1153 		return;
1154 	if (pp != NULL || cp != NULL)
1155 		return;	/* Nothing here. */
1156 
1157 	sbuf_printf(sb, "%s<KeysTotal>%ju</KeysTotal>\n", indent,
1158 	    (uintmax_t)sc->sc_ekeys_total);
1159 	sbuf_printf(sb, "%s<KeysAllocated>%ju</KeysAllocated>\n", indent,
1160 	    (uintmax_t)sc->sc_ekeys_allocated);
1161 	sbuf_printf(sb, "%s<Flags>", indent);
1162 	if (sc->sc_flags == 0)
1163 		sbuf_printf(sb, "NONE");
1164 	else {
1165 		int first = 1;
1166 
1167 #define ADD_FLAG(flag, name)	do {					\
1168 	if (sc->sc_flags & (flag)) {					\
1169 		if (!first)						\
1170 			sbuf_printf(sb, ", ");				\
1171 		else							\
1172 			first = 0;					\
1173 		sbuf_printf(sb, name);					\
1174 	}								\
1175 } while (0)
1176 		ADD_FLAG(G_ELI_FLAG_SUSPEND, "SUSPEND");
1177 		ADD_FLAG(G_ELI_FLAG_SINGLE_KEY, "SINGLE-KEY");
1178 		ADD_FLAG(G_ELI_FLAG_NATIVE_BYTE_ORDER, "NATIVE-BYTE-ORDER");
1179 		ADD_FLAG(G_ELI_FLAG_ONETIME, "ONETIME");
1180 		ADD_FLAG(G_ELI_FLAG_BOOT, "BOOT");
1181 		ADD_FLAG(G_ELI_FLAG_WO_DETACH, "W-DETACH");
1182 		ADD_FLAG(G_ELI_FLAG_RW_DETACH, "RW-DETACH");
1183 		ADD_FLAG(G_ELI_FLAG_AUTH, "AUTH");
1184 		ADD_FLAG(G_ELI_FLAG_WOPEN, "W-OPEN");
1185 		ADD_FLAG(G_ELI_FLAG_DESTROY, "DESTROY");
1186 		ADD_FLAG(G_ELI_FLAG_RO, "READ-ONLY");
1187 		ADD_FLAG(G_ELI_FLAG_NODELETE, "NODELETE");
1188 		ADD_FLAG(G_ELI_FLAG_GELIBOOT, "GELIBOOT");
1189 #undef  ADD_FLAG
1190 	}
1191 	sbuf_printf(sb, "</Flags>\n");
1192 
1193 	if (!(sc->sc_flags & G_ELI_FLAG_ONETIME)) {
1194 		sbuf_printf(sb, "%s<UsedKey>%u</UsedKey>\n", indent,
1195 		    sc->sc_nkey);
1196 	}
1197 	sbuf_printf(sb, "%s<Version>%u</Version>\n", indent, sc->sc_version);
1198 	sbuf_printf(sb, "%s<Crypto>", indent);
1199 	switch (sc->sc_crypto) {
1200 	case G_ELI_CRYPTO_HW:
1201 		sbuf_printf(sb, "hardware");
1202 		break;
1203 	case G_ELI_CRYPTO_SW:
1204 		sbuf_printf(sb, "software");
1205 		break;
1206 	default:
1207 		sbuf_printf(sb, "UNKNOWN");
1208 		break;
1209 	}
1210 	sbuf_printf(sb, "</Crypto>\n");
1211 	if (sc->sc_flags & G_ELI_FLAG_AUTH) {
1212 		sbuf_printf(sb,
1213 		    "%s<AuthenticationAlgorithm>%s</AuthenticationAlgorithm>\n",
1214 		    indent, g_eli_algo2str(sc->sc_aalgo));
1215 	}
1216 	sbuf_printf(sb, "%s<KeyLength>%u</KeyLength>\n", indent,
1217 	    sc->sc_ekeylen);
1218 	sbuf_printf(sb, "%s<EncryptionAlgorithm>%s</EncryptionAlgorithm>\n",
1219 	    indent, g_eli_algo2str(sc->sc_ealgo));
1220 	sbuf_printf(sb, "%s<State>%s</State>\n", indent,
1221 	    (sc->sc_flags & G_ELI_FLAG_SUSPEND) ? "SUSPENDED" : "ACTIVE");
1222 }
1223 
1224 static void
1225 g_eli_shutdown_pre_sync(void *arg, int howto)
1226 {
1227 	struct g_class *mp;
1228 	struct g_geom *gp, *gp2;
1229 	struct g_provider *pp;
1230 	struct g_eli_softc *sc;
1231 	int error;
1232 
1233 	mp = arg;
1234 	g_topology_lock();
1235 	LIST_FOREACH_SAFE(gp, &mp->geom, geom, gp2) {
1236 		sc = gp->softc;
1237 		if (sc == NULL)
1238 			continue;
1239 		pp = LIST_FIRST(&gp->provider);
1240 		KASSERT(pp != NULL, ("No provider? gp=%p (%s)", gp, gp->name));
1241 		if (pp->acr + pp->acw + pp->ace == 0)
1242 			error = g_eli_destroy(sc, TRUE);
1243 		else {
1244 			sc->sc_flags |= G_ELI_FLAG_RW_DETACH;
1245 			gp->access = g_eli_access;
1246 		}
1247 	}
1248 	g_topology_unlock();
1249 }
1250 
1251 static void
1252 g_eli_init(struct g_class *mp)
1253 {
1254 
1255 	g_eli_pre_sync = EVENTHANDLER_REGISTER(shutdown_pre_sync,
1256 	    g_eli_shutdown_pre_sync, mp, SHUTDOWN_PRI_FIRST);
1257 	if (g_eli_pre_sync == NULL)
1258 		G_ELI_DEBUG(0, "Warning! Cannot register shutdown event.");
1259 }
1260 
1261 static void
1262 g_eli_fini(struct g_class *mp)
1263 {
1264 
1265 	if (g_eli_pre_sync != NULL)
1266 		EVENTHANDLER_DEREGISTER(shutdown_pre_sync, g_eli_pre_sync);
1267 }
1268 
1269 DECLARE_GEOM_CLASS(g_eli_class, g_eli);
1270 MODULE_DEPEND(g_eli, crypto, 1, 1, 1);
1271