xref: /freebsd/sys/geom/eli/g_eli.c (revision 48855ec75316aaec5538ef22132f96fd04e137d4)
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/kernel.h>
33 #include <sys/linker.h>
34 #include <sys/module.h>
35 #include <sys/lock.h>
36 #include <sys/mutex.h>
37 #include <sys/bio.h>
38 #include <sys/sysctl.h>
39 #include <sys/malloc.h>
40 #include <sys/eventhandler.h>
41 #include <sys/kthread.h>
42 #include <sys/proc.h>
43 #include <sys/sched.h>
44 #include <sys/smp.h>
45 #include <sys/uio.h>
46 #include <sys/vnode.h>
47 
48 #include <vm/uma.h>
49 
50 #include <geom/geom.h>
51 #include <geom/eli/g_eli.h>
52 #include <geom/eli/pkcs5v2.h>
53 
54 FEATURE(geom_eli, "GEOM crypto module");
55 
56 MALLOC_DEFINE(M_ELI, "eli data", "GEOM_ELI Data");
57 
58 SYSCTL_DECL(_kern_geom);
59 SYSCTL_NODE(_kern_geom, OID_AUTO, eli, CTLFLAG_RW, 0, "GEOM_ELI stuff");
60 int g_eli_debug = 0;
61 TUNABLE_INT("kern.geom.eli.debug", &g_eli_debug);
62 SYSCTL_INT(_kern_geom_eli, OID_AUTO, debug, CTLFLAG_RW, &g_eli_debug, 0,
63     "Debug level");
64 static u_int g_eli_tries = 3;
65 TUNABLE_INT("kern.geom.eli.tries", &g_eli_tries);
66 SYSCTL_UINT(_kern_geom_eli, OID_AUTO, tries, CTLFLAG_RW, &g_eli_tries, 0,
67     "Number of tries for entering the passphrase");
68 static u_int g_eli_visible_passphrase = GETS_NOECHO;
69 TUNABLE_INT("kern.geom.eli.visible_passphrase", &g_eli_visible_passphrase);
70 SYSCTL_UINT(_kern_geom_eli, OID_AUTO, visible_passphrase, CTLFLAG_RW,
71     &g_eli_visible_passphrase, 0,
72     "Visibility of passphrase prompt (0 = invisible, 1 = visible, 2 = asterisk)");
73 u_int g_eli_overwrites = G_ELI_OVERWRITES;
74 TUNABLE_INT("kern.geom.eli.overwrites", &g_eli_overwrites);
75 SYSCTL_UINT(_kern_geom_eli, OID_AUTO, overwrites, CTLFLAG_RW, &g_eli_overwrites,
76     0, "Number of times on-disk keys should be overwritten when destroying them");
77 static u_int g_eli_threads = 0;
78 TUNABLE_INT("kern.geom.eli.threads", &g_eli_threads);
79 SYSCTL_UINT(_kern_geom_eli, OID_AUTO, threads, CTLFLAG_RW, &g_eli_threads, 0,
80     "Number of threads doing crypto work");
81 u_int g_eli_batch = 0;
82 TUNABLE_INT("kern.geom.eli.batch", &g_eli_batch);
83 SYSCTL_UINT(_kern_geom_eli, OID_AUTO, batch, CTLFLAG_RW, &g_eli_batch, 0,
84     "Use crypto operations batching");
85 
86 static eventhandler_tag g_eli_pre_sync = NULL;
87 
88 static int g_eli_destroy_geom(struct gctl_req *req, struct g_class *mp,
89     struct g_geom *gp);
90 static void g_eli_init(struct g_class *mp);
91 static void g_eli_fini(struct g_class *mp);
92 
93 static g_taste_t g_eli_taste;
94 static g_dumpconf_t g_eli_dumpconf;
95 
96 struct g_class g_eli_class = {
97 	.name = G_ELI_CLASS_NAME,
98 	.version = G_VERSION,
99 	.ctlreq = g_eli_config,
100 	.taste = g_eli_taste,
101 	.destroy_geom = g_eli_destroy_geom,
102 	.init = g_eli_init,
103 	.fini = g_eli_fini
104 };
105 
106 
107 /*
108  * Code paths:
109  * BIO_READ:
110  *	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
111  * BIO_WRITE:
112  *	g_eli_start -> g_eli_crypto_run -> g_eli_crypto_write_done -> g_io_request -> g_eli_write_done -> g_io_deliver
113  */
114 
115 
116 /*
117  * EAGAIN from crypto(9) means, that we were probably balanced to another crypto
118  * accelerator or something like this.
119  * The function updates the SID and rerun the operation.
120  */
121 int
122 g_eli_crypto_rerun(struct cryptop *crp)
123 {
124 	struct g_eli_softc *sc;
125 	struct g_eli_worker *wr;
126 	struct bio *bp;
127 	int error;
128 
129 	bp = (struct bio *)crp->crp_opaque;
130 	sc = bp->bio_to->geom->softc;
131 	LIST_FOREACH(wr, &sc->sc_workers, w_next) {
132 		if (wr->w_number == bp->bio_pflags)
133 			break;
134 	}
135 	KASSERT(wr != NULL, ("Invalid worker (%u).", bp->bio_pflags));
136 	G_ELI_DEBUG(1, "Rerunning crypto %s request (sid: %ju -> %ju).",
137 	    bp->bio_cmd == BIO_READ ? "READ" : "WRITE", (uintmax_t)wr->w_sid,
138 	    (uintmax_t)crp->crp_sid);
139 	wr->w_sid = crp->crp_sid;
140 	crp->crp_etype = 0;
141 	error = crypto_dispatch(crp);
142 	if (error == 0)
143 		return (0);
144 	G_ELI_DEBUG(1, "%s: crypto_dispatch() returned %d.", __func__, error);
145 	crp->crp_etype = error;
146 	return (error);
147 }
148 
149 /*
150  * The function is called afer reading encrypted data from the provider.
151  *
152  * 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
153  */
154 void
155 g_eli_read_done(struct bio *bp)
156 {
157 	struct g_eli_softc *sc;
158 	struct bio *pbp;
159 
160 	G_ELI_LOGREQ(2, bp, "Request done.");
161 	pbp = bp->bio_parent;
162 	if (pbp->bio_error == 0)
163 		pbp->bio_error = bp->bio_error;
164 	g_destroy_bio(bp);
165 	/*
166 	 * Do we have all sectors already?
167 	 */
168 	pbp->bio_inbed++;
169 	if (pbp->bio_inbed < pbp->bio_children)
170 		return;
171 	sc = pbp->bio_to->geom->softc;
172 	if (pbp->bio_error != 0) {
173 		G_ELI_LOGREQ(0, pbp, "%s() failed", __func__);
174 		pbp->bio_completed = 0;
175 		if (pbp->bio_driver2 != NULL) {
176 			free(pbp->bio_driver2, M_ELI);
177 			pbp->bio_driver2 = NULL;
178 		}
179 		g_io_deliver(pbp, pbp->bio_error);
180 		atomic_subtract_int(&sc->sc_inflight, 1);
181 		return;
182 	}
183 	mtx_lock(&sc->sc_queue_mtx);
184 	bioq_insert_tail(&sc->sc_queue, pbp);
185 	mtx_unlock(&sc->sc_queue_mtx);
186 	wakeup(sc);
187 }
188 
189 /*
190  * The function is called after we encrypt and write data.
191  *
192  * g_eli_start -> g_eli_crypto_run -> g_eli_crypto_write_done -> g_io_request -> G_ELI_WRITE_DONE -> g_io_deliver
193  */
194 void
195 g_eli_write_done(struct bio *bp)
196 {
197 	struct g_eli_softc *sc;
198 	struct bio *pbp;
199 
200 	G_ELI_LOGREQ(2, bp, "Request done.");
201 	pbp = bp->bio_parent;
202 	if (pbp->bio_error == 0) {
203 		if (bp->bio_error != 0)
204 			pbp->bio_error = bp->bio_error;
205 	}
206 	g_destroy_bio(bp);
207 	/*
208 	 * Do we have all sectors already?
209 	 */
210 	pbp->bio_inbed++;
211 	if (pbp->bio_inbed < pbp->bio_children)
212 		return;
213 	free(pbp->bio_driver2, M_ELI);
214 	pbp->bio_driver2 = NULL;
215 	if (pbp->bio_error != 0) {
216 		G_ELI_LOGREQ(0, pbp, "Crypto WRITE request failed (error=%d).",
217 		    pbp->bio_error);
218 		pbp->bio_completed = 0;
219 	}
220 	/*
221 	 * Write is finished, send it up.
222 	 */
223 	pbp->bio_completed = pbp->bio_length;
224 	sc = pbp->bio_to->geom->softc;
225 	g_io_deliver(pbp, pbp->bio_error);
226 	atomic_subtract_int(&sc->sc_inflight, 1);
227 }
228 
229 /*
230  * This function should never be called, but GEOM made as it set ->orphan()
231  * method for every geom.
232  */
233 static void
234 g_eli_orphan_spoil_assert(struct g_consumer *cp)
235 {
236 
237 	panic("Function %s() called for %s.", __func__, cp->geom->name);
238 }
239 
240 static void
241 g_eli_orphan(struct g_consumer *cp)
242 {
243 	struct g_eli_softc *sc;
244 
245 	g_topology_assert();
246 	sc = cp->geom->softc;
247 	if (sc == NULL)
248 		return;
249 	g_eli_destroy(sc, TRUE);
250 }
251 
252 /*
253  * BIO_READ:
254  *	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
255  * BIO_WRITE:
256  *	G_ELI_START -> g_eli_crypto_run -> g_eli_crypto_write_done -> g_io_request -> g_eli_write_done -> g_io_deliver
257  */
258 static void
259 g_eli_start(struct bio *bp)
260 {
261 	struct g_eli_softc *sc;
262 	struct g_consumer *cp;
263 	struct bio *cbp;
264 
265 	sc = bp->bio_to->geom->softc;
266 	KASSERT(sc != NULL,
267 	    ("Provider's error should be set (error=%d)(device=%s).",
268 	    bp->bio_to->error, bp->bio_to->name));
269 	G_ELI_LOGREQ(2, bp, "Request received.");
270 
271 	switch (bp->bio_cmd) {
272 	case BIO_READ:
273 	case BIO_WRITE:
274 	case BIO_GETATTR:
275 	case BIO_FLUSH:
276 		break;
277 	case BIO_DELETE:
278 		/*
279 		 * We could eventually support BIO_DELETE request.
280 		 * It could be done by overwritting requested sector with
281 		 * random data g_eli_overwrites number of times.
282 		 */
283 	default:
284 		g_io_deliver(bp, EOPNOTSUPP);
285 		return;
286 	}
287 	cbp = g_clone_bio(bp);
288 	if (cbp == NULL) {
289 		g_io_deliver(bp, ENOMEM);
290 		return;
291 	}
292 	bp->bio_driver1 = cbp;
293 	bp->bio_pflags = G_ELI_NEW_BIO;
294 	switch (bp->bio_cmd) {
295 	case BIO_READ:
296 		if (!(sc->sc_flags & G_ELI_FLAG_AUTH)) {
297 			g_eli_crypto_read(sc, bp, 0);
298 			break;
299 		}
300 		/* FALLTHROUGH */
301 	case BIO_WRITE:
302 		mtx_lock(&sc->sc_queue_mtx);
303 		bioq_insert_tail(&sc->sc_queue, bp);
304 		mtx_unlock(&sc->sc_queue_mtx);
305 		wakeup(sc);
306 		break;
307 	case BIO_GETATTR:
308 	case BIO_FLUSH:
309 		cbp->bio_done = g_std_done;
310 		cp = LIST_FIRST(&sc->sc_geom->consumer);
311 		cbp->bio_to = cp->provider;
312 		G_ELI_LOGREQ(2, cbp, "Sending request.");
313 		g_io_request(cbp, cp);
314 		break;
315 	}
316 }
317 
318 static int
319 g_eli_newsession(struct g_eli_worker *wr)
320 {
321 	struct g_eli_softc *sc;
322 	struct cryptoini crie, cria;
323 	int error;
324 
325 	sc = wr->w_softc;
326 
327 	bzero(&crie, sizeof(crie));
328 	crie.cri_alg = sc->sc_ealgo;
329 	crie.cri_klen = sc->sc_ekeylen;
330 	if (sc->sc_ealgo == CRYPTO_AES_XTS)
331 		crie.cri_klen <<= 1;
332 	crie.cri_key = sc->sc_ekey;
333 	if (sc->sc_flags & G_ELI_FLAG_AUTH) {
334 		bzero(&cria, sizeof(cria));
335 		cria.cri_alg = sc->sc_aalgo;
336 		cria.cri_klen = sc->sc_akeylen;
337 		cria.cri_key = sc->sc_akey;
338 		crie.cri_next = &cria;
339 	}
340 
341 	switch (sc->sc_crypto) {
342 	case G_ELI_CRYPTO_SW:
343 		error = crypto_newsession(&wr->w_sid, &crie,
344 		    CRYPTOCAP_F_SOFTWARE);
345 		break;
346 	case G_ELI_CRYPTO_HW:
347 		error = crypto_newsession(&wr->w_sid, &crie,
348 		    CRYPTOCAP_F_HARDWARE);
349 		break;
350 	case G_ELI_CRYPTO_UNKNOWN:
351 		error = crypto_newsession(&wr->w_sid, &crie,
352 		    CRYPTOCAP_F_HARDWARE);
353 		if (error == 0) {
354 			mtx_lock(&sc->sc_queue_mtx);
355 			if (sc->sc_crypto == G_ELI_CRYPTO_UNKNOWN)
356 				sc->sc_crypto = G_ELI_CRYPTO_HW;
357 			mtx_unlock(&sc->sc_queue_mtx);
358 		} else {
359 			error = crypto_newsession(&wr->w_sid, &crie,
360 			    CRYPTOCAP_F_SOFTWARE);
361 			mtx_lock(&sc->sc_queue_mtx);
362 			if (sc->sc_crypto == G_ELI_CRYPTO_UNKNOWN)
363 				sc->sc_crypto = G_ELI_CRYPTO_SW;
364 			mtx_unlock(&sc->sc_queue_mtx);
365 		}
366 		break;
367 	default:
368 		panic("%s: invalid condition", __func__);
369 	}
370 
371 	return (error);
372 }
373 
374 static void
375 g_eli_freesession(struct g_eli_worker *wr)
376 {
377 
378 	crypto_freesession(wr->w_sid);
379 }
380 
381 static void
382 g_eli_cancel(struct g_eli_softc *sc)
383 {
384 	struct bio *bp;
385 
386 	mtx_assert(&sc->sc_queue_mtx, MA_OWNED);
387 
388 	while ((bp = bioq_takefirst(&sc->sc_queue)) != NULL) {
389 		KASSERT(bp->bio_pflags == G_ELI_NEW_BIO,
390 		    ("Not new bio when canceling (bp=%p).", bp));
391 		g_io_deliver(bp, ENXIO);
392 	}
393 }
394 
395 static struct bio *
396 g_eli_takefirst(struct g_eli_softc *sc)
397 {
398 	struct bio *bp;
399 
400 	mtx_assert(&sc->sc_queue_mtx, MA_OWNED);
401 
402 	if (!(sc->sc_flags & G_ELI_FLAG_SUSPEND))
403 		return (bioq_takefirst(&sc->sc_queue));
404 	/*
405 	 * Device suspended, so we skip new I/O requests.
406 	 */
407 	TAILQ_FOREACH(bp, &sc->sc_queue.queue, bio_queue) {
408 		if (bp->bio_pflags != G_ELI_NEW_BIO)
409 			break;
410 	}
411 	if (bp != NULL)
412 		bioq_remove(&sc->sc_queue, bp);
413 	return (bp);
414 }
415 
416 /*
417  * This is the main function for kernel worker thread when we don't have
418  * hardware acceleration and we have to do cryptography in software.
419  * Dedicated thread is needed, so we don't slow down g_up/g_down GEOM
420  * threads with crypto work.
421  */
422 static void
423 g_eli_worker(void *arg)
424 {
425 	struct g_eli_softc *sc;
426 	struct g_eli_worker *wr;
427 	struct bio *bp;
428 	int error;
429 
430 	wr = arg;
431 	sc = wr->w_softc;
432 #ifdef SMP
433 	/* Before sched_bind() to a CPU, wait for all CPUs to go on-line. */
434 	if (mp_ncpus > 1 && sc->sc_crypto == G_ELI_CRYPTO_SW &&
435 	    g_eli_threads == 0) {
436 		while (!smp_started)
437 			tsleep(wr, 0, "geli:smp", hz / 4);
438 	}
439 #endif
440 	thread_lock(curthread);
441 	sched_prio(curthread, PUSER);
442 	if (sc->sc_crypto == G_ELI_CRYPTO_SW && g_eli_threads == 0)
443 		sched_bind(curthread, wr->w_number);
444 	thread_unlock(curthread);
445 
446 	G_ELI_DEBUG(1, "Thread %s started.", curthread->td_proc->p_comm);
447 
448 	for (;;) {
449 		mtx_lock(&sc->sc_queue_mtx);
450 again:
451 		bp = g_eli_takefirst(sc);
452 		if (bp == NULL) {
453 			if (sc->sc_flags & G_ELI_FLAG_DESTROY) {
454 				g_eli_cancel(sc);
455 				LIST_REMOVE(wr, w_next);
456 				g_eli_freesession(wr);
457 				free(wr, M_ELI);
458 				G_ELI_DEBUG(1, "Thread %s exiting.",
459 				    curthread->td_proc->p_comm);
460 				wakeup(&sc->sc_workers);
461 				mtx_unlock(&sc->sc_queue_mtx);
462 				kproc_exit(0);
463 			}
464 			while (sc->sc_flags & G_ELI_FLAG_SUSPEND) {
465 				if (sc->sc_inflight > 0) {
466 					G_ELI_DEBUG(0, "inflight=%d", sc->sc_inflight);
467 					/*
468 					 * We still have inflight BIOs, so
469 					 * sleep and retry.
470 					 */
471 					msleep(sc, &sc->sc_queue_mtx, PRIBIO,
472 					    "geli:inf", hz / 5);
473 					goto again;
474 				}
475 				/*
476 				 * Suspend requested, mark the worker as
477 				 * suspended and go to sleep.
478 				 */
479 				if (wr->w_active) {
480 					g_eli_freesession(wr);
481 					wr->w_active = FALSE;
482 				}
483 				wakeup(&sc->sc_workers);
484 				msleep(sc, &sc->sc_queue_mtx, PRIBIO,
485 				    "geli:suspend", 0);
486 				if (!wr->w_active &&
487 				    !(sc->sc_flags & G_ELI_FLAG_SUSPEND)) {
488 					error = g_eli_newsession(wr);
489 					KASSERT(error == 0,
490 					    ("g_eli_newsession() failed on resume (error=%d)",
491 					    error));
492 					wr->w_active = TRUE;
493 				}
494 				goto again;
495 			}
496 			msleep(sc, &sc->sc_queue_mtx, PDROP, "geli:w", 0);
497 			continue;
498 		}
499 		if (bp->bio_pflags == G_ELI_NEW_BIO)
500 			atomic_add_int(&sc->sc_inflight, 1);
501 		mtx_unlock(&sc->sc_queue_mtx);
502 		if (bp->bio_pflags == G_ELI_NEW_BIO) {
503 			bp->bio_pflags = 0;
504 			if (sc->sc_flags & G_ELI_FLAG_AUTH) {
505 				if (bp->bio_cmd == BIO_READ)
506 					g_eli_auth_read(sc, bp);
507 				else
508 					g_eli_auth_run(wr, bp);
509 			} else {
510 				if (bp->bio_cmd == BIO_READ)
511 					g_eli_crypto_read(sc, bp, 1);
512 				else
513 					g_eli_crypto_run(wr, bp);
514 			}
515 		} else {
516 			if (sc->sc_flags & G_ELI_FLAG_AUTH)
517 				g_eli_auth_run(wr, bp);
518 			else
519 				g_eli_crypto_run(wr, bp);
520 		}
521 	}
522 }
523 
524 /*
525  * Here we generate IV. It is unique for every sector.
526  */
527 void
528 g_eli_crypto_ivgen(struct g_eli_softc *sc, off_t offset, u_char *iv,
529     size_t size)
530 {
531 	uint8_t off[8];
532 
533 	if ((sc->sc_flags & G_ELI_FLAG_NATIVE_BYTE_ORDER) != 0)
534 		bcopy(&offset, off, sizeof(off));
535 	else
536 		le64enc(off, (uint64_t)offset);
537 
538 	switch (sc->sc_ealgo) {
539 	case CRYPTO_AES_XTS:
540 		bcopy(off, iv, sizeof(off));
541 		bzero(iv + sizeof(off), size - sizeof(off));
542 		break;
543 	default:
544 	    {
545 		u_char hash[SHA256_DIGEST_LENGTH];
546 		SHA256_CTX ctx;
547 
548 		/* Copy precalculated SHA256 context for IV-Key. */
549 		bcopy(&sc->sc_ivctx, &ctx, sizeof(ctx));
550 		SHA256_Update(&ctx, off, sizeof(off));
551 		SHA256_Final(hash, &ctx);
552 		bcopy(hash, iv, MIN(sizeof(hash), size));
553 		break;
554 	    }
555 	}
556 }
557 
558 int
559 g_eli_read_metadata(struct g_class *mp, struct g_provider *pp,
560     struct g_eli_metadata *md)
561 {
562 	struct g_geom *gp;
563 	struct g_consumer *cp;
564 	u_char *buf = NULL;
565 	int error;
566 
567 	g_topology_assert();
568 
569 	gp = g_new_geomf(mp, "eli:taste");
570 	gp->start = g_eli_start;
571 	gp->access = g_std_access;
572 	/*
573 	 * g_eli_read_metadata() is always called from the event thread.
574 	 * Our geom is created and destroyed in the same event, so there
575 	 * could be no orphan nor spoil event in the meantime.
576 	 */
577 	gp->orphan = g_eli_orphan_spoil_assert;
578 	gp->spoiled = g_eli_orphan_spoil_assert;
579 	cp = g_new_consumer(gp);
580 	error = g_attach(cp, pp);
581 	if (error != 0)
582 		goto end;
583 	error = g_access(cp, 1, 0, 0);
584 	if (error != 0)
585 		goto end;
586 	g_topology_unlock();
587 	buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
588 	    &error);
589 	g_topology_lock();
590 	if (buf == NULL)
591 		goto end;
592 	eli_metadata_decode(buf, md);
593 end:
594 	if (buf != NULL)
595 		g_free(buf);
596 	if (cp->provider != NULL) {
597 		if (cp->acr == 1)
598 			g_access(cp, -1, 0, 0);
599 		g_detach(cp);
600 	}
601 	g_destroy_consumer(cp);
602 	g_destroy_geom(gp);
603 	return (error);
604 }
605 
606 /*
607  * The function is called when we had last close on provider and user requested
608  * to close it when this situation occur.
609  */
610 static void
611 g_eli_last_close(struct g_eli_softc *sc)
612 {
613 	struct g_geom *gp;
614 	struct g_provider *pp;
615 	char ppname[64];
616 	int error;
617 
618 	g_topology_assert();
619 	gp = sc->sc_geom;
620 	pp = LIST_FIRST(&gp->provider);
621 	strlcpy(ppname, pp->name, sizeof(ppname));
622 	error = g_eli_destroy(sc, TRUE);
623 	KASSERT(error == 0, ("Cannot detach %s on last close (error=%d).",
624 	    ppname, error));
625 	G_ELI_DEBUG(0, "Detached %s on last close.", ppname);
626 }
627 
628 int
629 g_eli_access(struct g_provider *pp, int dr, int dw, int de)
630 {
631 	struct g_eli_softc *sc;
632 	struct g_geom *gp;
633 
634 	gp = pp->geom;
635 	sc = gp->softc;
636 
637 	if (dw > 0) {
638 		if (sc->sc_flags & G_ELI_FLAG_RO) {
639 			/* Deny write attempts. */
640 			return (EROFS);
641 		}
642 		/* Someone is opening us for write, we need to remember that. */
643 		sc->sc_flags |= G_ELI_FLAG_WOPEN;
644 		return (0);
645 	}
646 	/* Is this the last close? */
647 	if (pp->acr + dr > 0 || pp->acw + dw > 0 || pp->ace + de > 0)
648 		return (0);
649 
650 	/*
651 	 * Automatically detach on last close if requested.
652 	 */
653 	if ((sc->sc_flags & G_ELI_FLAG_RW_DETACH) ||
654 	    (sc->sc_flags & G_ELI_FLAG_WOPEN)) {
655 		g_eli_last_close(sc);
656 	}
657 	return (0);
658 }
659 
660 static int
661 g_eli_cpu_is_disabled(int cpu)
662 {
663 #ifdef SMP
664 	return ((hlt_cpus_mask & (1 << cpu)) != 0);
665 #else
666 	return (0);
667 #endif
668 }
669 
670 struct g_geom *
671 g_eli_create(struct gctl_req *req, struct g_class *mp, struct g_provider *bpp,
672     const struct g_eli_metadata *md, const u_char *mkey, int nkey)
673 {
674 	struct g_eli_softc *sc;
675 	struct g_eli_worker *wr;
676 	struct g_geom *gp;
677 	struct g_provider *pp;
678 	struct g_consumer *cp;
679 	u_int i, threads;
680 	int error;
681 
682 	G_ELI_DEBUG(1, "Creating device %s%s.", bpp->name, G_ELI_SUFFIX);
683 
684 	gp = g_new_geomf(mp, "%s%s", bpp->name, G_ELI_SUFFIX);
685 	gp->softc = NULL;	/* for a moment */
686 
687 	sc = malloc(sizeof(*sc), M_ELI, M_WAITOK | M_ZERO);
688 	gp->start = g_eli_start;
689 	/*
690 	 * Spoiling cannot happen actually, because we keep provider open for
691 	 * writing all the time or provider is read-only.
692 	 */
693 	gp->spoiled = g_eli_orphan_spoil_assert;
694 	gp->orphan = g_eli_orphan;
695 	gp->dumpconf = g_eli_dumpconf;
696 	/*
697 	 * If detach-on-last-close feature is not enabled and we don't operate
698 	 * on read-only provider, we can simply use g_std_access().
699 	 */
700 	if (md->md_flags & (G_ELI_FLAG_WO_DETACH | G_ELI_FLAG_RO))
701 		gp->access = g_eli_access;
702 	else
703 		gp->access = g_std_access;
704 
705 	sc->sc_inflight = 0;
706 	sc->sc_crypto = G_ELI_CRYPTO_UNKNOWN;
707 	sc->sc_flags = md->md_flags;
708 	/* Backward compatibility. */
709 	if (md->md_version < 4)
710 		sc->sc_flags |= G_ELI_FLAG_NATIVE_BYTE_ORDER;
711 	if (md->md_version < 5)
712 		sc->sc_flags |= G_ELI_FLAG_SINGLE_KEY;
713 	sc->sc_ealgo = md->md_ealgo;
714 	sc->sc_nkey = nkey;
715 
716 	if (sc->sc_flags & G_ELI_FLAG_AUTH) {
717 		sc->sc_akeylen = sizeof(sc->sc_akey) * 8;
718 		sc->sc_aalgo = md->md_aalgo;
719 		sc->sc_alen = g_eli_hashlen(sc->sc_aalgo);
720 
721 		sc->sc_data_per_sector = bpp->sectorsize - sc->sc_alen;
722 		/*
723 		 * Some hash functions (like SHA1 and RIPEMD160) generates hash
724 		 * which length is not multiple of 128 bits, but we want data
725 		 * length to be multiple of 128, so we can encrypt without
726 		 * padding. The line below rounds down data length to multiple
727 		 * of 128 bits.
728 		 */
729 		sc->sc_data_per_sector -= sc->sc_data_per_sector % 16;
730 
731 		sc->sc_bytes_per_sector =
732 		    (md->md_sectorsize - 1) / sc->sc_data_per_sector + 1;
733 		sc->sc_bytes_per_sector *= bpp->sectorsize;
734 	}
735 
736 	gp->softc = sc;
737 	sc->sc_geom = gp;
738 
739 	bioq_init(&sc->sc_queue);
740 	mtx_init(&sc->sc_queue_mtx, "geli:queue", NULL, MTX_DEF);
741 	mtx_init(&sc->sc_ekeys_lock, "geli:ekeys", NULL, MTX_DEF);
742 
743 	pp = NULL;
744 	cp = g_new_consumer(gp);
745 	error = g_attach(cp, bpp);
746 	if (error != 0) {
747 		if (req != NULL) {
748 			gctl_error(req, "Cannot attach to %s (error=%d).",
749 			    bpp->name, error);
750 		} else {
751 			G_ELI_DEBUG(1, "Cannot attach to %s (error=%d).",
752 			    bpp->name, error);
753 		}
754 		goto failed;
755 	}
756 	/*
757 	 * Keep provider open all the time, so we can run critical tasks,
758 	 * like Master Keys deletion, without wondering if we can open
759 	 * provider or not.
760 	 * We don't open provider for writing only when user requested read-only
761 	 * access.
762 	 */
763 	if (sc->sc_flags & G_ELI_FLAG_RO)
764 		error = g_access(cp, 1, 0, 1);
765 	else
766 		error = g_access(cp, 1, 1, 1);
767 	if (error != 0) {
768 		if (req != NULL) {
769 			gctl_error(req, "Cannot access %s (error=%d).",
770 			    bpp->name, error);
771 		} else {
772 			G_ELI_DEBUG(1, "Cannot access %s (error=%d).",
773 			    bpp->name, error);
774 		}
775 		goto failed;
776 	}
777 
778 	sc->sc_sectorsize = md->md_sectorsize;
779 	sc->sc_mediasize = bpp->mediasize;
780 	if (!(sc->sc_flags & G_ELI_FLAG_ONETIME))
781 		sc->sc_mediasize -= bpp->sectorsize;
782 	if (!(sc->sc_flags & G_ELI_FLAG_AUTH))
783 		sc->sc_mediasize -= (sc->sc_mediasize % sc->sc_sectorsize);
784 	else {
785 		sc->sc_mediasize /= sc->sc_bytes_per_sector;
786 		sc->sc_mediasize *= sc->sc_sectorsize;
787 	}
788 
789 	/*
790 	 * Remember the keys in our softc structure.
791 	 */
792 	g_eli_mkey_propagate(sc, mkey);
793 	sc->sc_ekeylen = md->md_keylen;
794 
795 	LIST_INIT(&sc->sc_workers);
796 
797 	threads = g_eli_threads;
798 	if (threads == 0)
799 		threads = mp_ncpus;
800 	else if (threads > mp_ncpus) {
801 		/* There is really no need for too many worker threads. */
802 		threads = mp_ncpus;
803 		G_ELI_DEBUG(0, "Reducing number of threads to %u.", threads);
804 	}
805 	for (i = 0; i < threads; i++) {
806 		if (g_eli_cpu_is_disabled(i)) {
807 			G_ELI_DEBUG(1, "%s: CPU %u disabled, skipping.",
808 			    bpp->name, i);
809 			continue;
810 		}
811 		wr = malloc(sizeof(*wr), M_ELI, M_WAITOK | M_ZERO);
812 		wr->w_softc = sc;
813 		wr->w_number = i;
814 		wr->w_active = TRUE;
815 
816 		error = g_eli_newsession(wr);
817 		if (error != 0) {
818 			free(wr, M_ELI);
819 			if (req != NULL) {
820 				gctl_error(req, "Cannot set up crypto session "
821 				    "for %s (error=%d).", bpp->name, error);
822 			} else {
823 				G_ELI_DEBUG(1, "Cannot set up crypto session "
824 				    "for %s (error=%d).", bpp->name, error);
825 			}
826 			goto failed;
827 		}
828 
829 		error = kproc_create(g_eli_worker, wr, &wr->w_proc, 0, 0,
830 		    "g_eli[%u] %s", i, bpp->name);
831 		if (error != 0) {
832 			g_eli_freesession(wr);
833 			free(wr, M_ELI);
834 			if (req != NULL) {
835 				gctl_error(req, "Cannot create kernel thread "
836 				    "for %s (error=%d).", bpp->name, error);
837 			} else {
838 				G_ELI_DEBUG(1, "Cannot create kernel thread "
839 				    "for %s (error=%d).", bpp->name, error);
840 			}
841 			goto failed;
842 		}
843 		LIST_INSERT_HEAD(&sc->sc_workers, wr, w_next);
844 		/* If we have hardware support, one thread is enough. */
845 		if (sc->sc_crypto == G_ELI_CRYPTO_HW)
846 			break;
847 	}
848 
849 	/*
850 	 * Create decrypted provider.
851 	 */
852 	pp = g_new_providerf(gp, "%s%s", bpp->name, G_ELI_SUFFIX);
853 	pp->mediasize = sc->sc_mediasize;
854 	pp->sectorsize = sc->sc_sectorsize;
855 
856 	g_error_provider(pp, 0);
857 
858 	G_ELI_DEBUG(0, "Device %s created.", pp->name);
859 	G_ELI_DEBUG(0, "Encryption: %s %u", g_eli_algo2str(sc->sc_ealgo),
860 	    sc->sc_ekeylen);
861 	if (sc->sc_flags & G_ELI_FLAG_AUTH)
862 		G_ELI_DEBUG(0, " Integrity: %s", g_eli_algo2str(sc->sc_aalgo));
863 	G_ELI_DEBUG(0, "    Crypto: %s",
864 	    sc->sc_crypto == G_ELI_CRYPTO_SW ? "software" : "hardware");
865 	return (gp);
866 failed:
867 	mtx_lock(&sc->sc_queue_mtx);
868 	sc->sc_flags |= G_ELI_FLAG_DESTROY;
869 	wakeup(sc);
870 	/*
871 	 * Wait for kernel threads self destruction.
872 	 */
873 	while (!LIST_EMPTY(&sc->sc_workers)) {
874 		msleep(&sc->sc_workers, &sc->sc_queue_mtx, PRIBIO,
875 		    "geli:destroy", 0);
876 	}
877 	mtx_destroy(&sc->sc_queue_mtx);
878 	if (cp->provider != NULL) {
879 		if (cp->acr == 1)
880 			g_access(cp, -1, -1, -1);
881 		g_detach(cp);
882 	}
883 	g_destroy_consumer(cp);
884 	g_destroy_geom(gp);
885 	g_eli_key_destroy(sc);
886 	bzero(sc, sizeof(*sc));
887 	free(sc, M_ELI);
888 	return (NULL);
889 }
890 
891 int
892 g_eli_destroy(struct g_eli_softc *sc, boolean_t force)
893 {
894 	struct g_geom *gp;
895 	struct g_provider *pp;
896 
897 	g_topology_assert();
898 
899 	if (sc == NULL)
900 		return (ENXIO);
901 
902 	gp = sc->sc_geom;
903 	pp = LIST_FIRST(&gp->provider);
904 	if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) {
905 		if (force) {
906 			G_ELI_DEBUG(1, "Device %s is still open, so it "
907 			    "cannot be definitely removed.", pp->name);
908 		} else {
909 			G_ELI_DEBUG(1,
910 			    "Device %s is still open (r%dw%de%d).", pp->name,
911 			    pp->acr, pp->acw, pp->ace);
912 			return (EBUSY);
913 		}
914 	}
915 
916 	mtx_lock(&sc->sc_queue_mtx);
917 	sc->sc_flags |= G_ELI_FLAG_DESTROY;
918 	wakeup(sc);
919 	while (!LIST_EMPTY(&sc->sc_workers)) {
920 		msleep(&sc->sc_workers, &sc->sc_queue_mtx, PRIBIO,
921 		    "geli:destroy", 0);
922 	}
923 	mtx_destroy(&sc->sc_queue_mtx);
924 	gp->softc = NULL;
925 	g_eli_key_destroy(sc);
926 	bzero(sc, sizeof(*sc));
927 	free(sc, M_ELI);
928 
929 	if (pp == NULL || (pp->acr == 0 && pp->acw == 0 && pp->ace == 0))
930 		G_ELI_DEBUG(0, "Device %s destroyed.", gp->name);
931 	g_wither_geom_close(gp, ENXIO);
932 
933 	return (0);
934 }
935 
936 static int
937 g_eli_destroy_geom(struct gctl_req *req __unused,
938     struct g_class *mp __unused, struct g_geom *gp)
939 {
940 	struct g_eli_softc *sc;
941 
942 	sc = gp->softc;
943 	return (g_eli_destroy(sc, FALSE));
944 }
945 
946 static int
947 g_eli_keyfiles_load(struct hmac_ctx *ctx, const char *provider)
948 {
949 	u_char *keyfile, *data;
950 	char *file, name[64];
951 	size_t size;
952 	int i;
953 
954 	for (i = 0; ; i++) {
955 		snprintf(name, sizeof(name), "%s:geli_keyfile%d", provider, i);
956 		keyfile = preload_search_by_type(name);
957 		if (keyfile == NULL)
958 			return (i);	/* Return number of loaded keyfiles. */
959 		data = preload_fetch_addr(keyfile);
960 		if (data == NULL) {
961 			G_ELI_DEBUG(0, "Cannot find key file data for %s.",
962 			    name);
963 			return (0);
964 		}
965 		size = preload_fetch_size(keyfile);
966 		if (size == 0) {
967 			G_ELI_DEBUG(0, "Cannot find key file size for %s.",
968 			    name);
969 			return (0);
970 		}
971 		file = preload_search_info(keyfile, MODINFO_NAME);
972 		if (file == NULL) {
973 			G_ELI_DEBUG(0, "Cannot find key file name for %s.",
974 			    name);
975 			return (0);
976 		}
977 		G_ELI_DEBUG(1, "Loaded keyfile %s for %s (type: %s).", file,
978 		    provider, name);
979 		g_eli_crypto_hmac_update(ctx, data, size);
980 	}
981 }
982 
983 static void
984 g_eli_keyfiles_clear(const char *provider)
985 {
986 	u_char *keyfile, *data;
987 	char name[64];
988 	size_t size;
989 	int i;
990 
991 	for (i = 0; ; i++) {
992 		snprintf(name, sizeof(name), "%s:geli_keyfile%d", provider, i);
993 		keyfile = preload_search_by_type(name);
994 		if (keyfile == NULL)
995 			return;
996 		data = preload_fetch_addr(keyfile);
997 		size = preload_fetch_size(keyfile);
998 		if (data != NULL && size != 0)
999 			bzero(data, size);
1000 	}
1001 }
1002 
1003 /*
1004  * Tasting is only made on boot.
1005  * We detect providers which should be attached before root is mounted.
1006  */
1007 static struct g_geom *
1008 g_eli_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
1009 {
1010 	struct g_eli_metadata md;
1011 	struct g_geom *gp;
1012 	struct hmac_ctx ctx;
1013 	char passphrase[256];
1014 	u_char key[G_ELI_USERKEYLEN], mkey[G_ELI_DATAIVKEYLEN];
1015 	u_int i, nkey, nkeyfiles, tries;
1016 	int error;
1017 
1018 	g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
1019 	g_topology_assert();
1020 
1021 	if (root_mounted() || g_eli_tries == 0)
1022 		return (NULL);
1023 
1024 	G_ELI_DEBUG(3, "Tasting %s.", pp->name);
1025 
1026 	error = g_eli_read_metadata(mp, pp, &md);
1027 	if (error != 0)
1028 		return (NULL);
1029 	gp = NULL;
1030 
1031 	if (strcmp(md.md_magic, G_ELI_MAGIC) != 0)
1032 		return (NULL);
1033 	if (md.md_version > G_ELI_VERSION) {
1034 		printf("geom_eli.ko module is too old to handle %s.\n",
1035 		    pp->name);
1036 		return (NULL);
1037 	}
1038 	if (md.md_provsize != pp->mediasize)
1039 		return (NULL);
1040 	/* Should we attach it on boot? */
1041 	if (!(md.md_flags & G_ELI_FLAG_BOOT))
1042 		return (NULL);
1043 	if (md.md_keys == 0x00) {
1044 		G_ELI_DEBUG(0, "No valid keys on %s.", pp->name);
1045 		return (NULL);
1046 	}
1047 	if (md.md_iterations == -1) {
1048 		/* If there is no passphrase, we try only once. */
1049 		tries = 1;
1050 	} else {
1051 		/* Ask for the passphrase no more than g_eli_tries times. */
1052 		tries = g_eli_tries;
1053 	}
1054 
1055 	for (i = 0; i < tries; i++) {
1056 		g_eli_crypto_hmac_init(&ctx, NULL, 0);
1057 
1058 		/*
1059 		 * Load all key files.
1060 		 */
1061 		nkeyfiles = g_eli_keyfiles_load(&ctx, pp->name);
1062 
1063 		if (nkeyfiles == 0 && md.md_iterations == -1) {
1064 			/*
1065 			 * No key files and no passphrase, something is
1066 			 * definitely wrong here.
1067 			 * geli(8) doesn't allow for such situation, so assume
1068 			 * that there was really no passphrase and in that case
1069 			 * key files are no properly defined in loader.conf.
1070 			 */
1071 			G_ELI_DEBUG(0,
1072 			    "Found no key files in loader.conf for %s.",
1073 			    pp->name);
1074 			return (NULL);
1075 		}
1076 
1077 		/* Ask for the passphrase if defined. */
1078 		if (md.md_iterations >= 0) {
1079 			printf("Enter passphrase for %s: ", pp->name);
1080 			gets(passphrase, sizeof(passphrase),
1081 			    g_eli_visible_passphrase);
1082 		}
1083 
1084 		/*
1085 		 * Prepare Derived-Key from the user passphrase.
1086 		 */
1087 		if (md.md_iterations == 0) {
1088 			g_eli_crypto_hmac_update(&ctx, md.md_salt,
1089 			    sizeof(md.md_salt));
1090 			g_eli_crypto_hmac_update(&ctx, passphrase,
1091 			    strlen(passphrase));
1092 			bzero(passphrase, sizeof(passphrase));
1093 		} else if (md.md_iterations > 0) {
1094 			u_char dkey[G_ELI_USERKEYLEN];
1095 
1096 			pkcs5v2_genkey(dkey, sizeof(dkey), md.md_salt,
1097 			    sizeof(md.md_salt), passphrase, md.md_iterations);
1098 			bzero(passphrase, sizeof(passphrase));
1099 			g_eli_crypto_hmac_update(&ctx, dkey, sizeof(dkey));
1100 			bzero(dkey, sizeof(dkey));
1101 		}
1102 
1103 		g_eli_crypto_hmac_final(&ctx, key, 0);
1104 
1105 		/*
1106 		 * Decrypt Master-Key.
1107 		 */
1108 		error = g_eli_mkey_decrypt(&md, key, mkey, &nkey);
1109 		bzero(key, sizeof(key));
1110 		if (error == -1) {
1111 			if (i == tries - 1) {
1112 				G_ELI_DEBUG(0,
1113 				    "Wrong key for %s. No tries left.",
1114 				    pp->name);
1115 				g_eli_keyfiles_clear(pp->name);
1116 				return (NULL);
1117 			}
1118 			G_ELI_DEBUG(0, "Wrong key for %s. Tries left: %u.",
1119 			    pp->name, tries - i - 1);
1120 			/* Try again. */
1121 			continue;
1122 		} else if (error > 0) {
1123 			G_ELI_DEBUG(0, "Cannot decrypt Master Key for %s (error=%d).",
1124 			    pp->name, error);
1125 			g_eli_keyfiles_clear(pp->name);
1126 			return (NULL);
1127 		}
1128 		G_ELI_DEBUG(1, "Using Master Key %u for %s.", nkey, pp->name);
1129 		break;
1130 	}
1131 
1132 	/*
1133 	 * We have correct key, let's attach provider.
1134 	 */
1135 	gp = g_eli_create(NULL, mp, pp, &md, mkey, nkey);
1136 	bzero(mkey, sizeof(mkey));
1137 	bzero(&md, sizeof(md));
1138 	if (gp == NULL) {
1139 		G_ELI_DEBUG(0, "Cannot create device %s%s.", pp->name,
1140 		    G_ELI_SUFFIX);
1141 		return (NULL);
1142 	}
1143 	return (gp);
1144 }
1145 
1146 static void
1147 g_eli_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
1148     struct g_consumer *cp, struct g_provider *pp)
1149 {
1150 	struct g_eli_softc *sc;
1151 
1152 	g_topology_assert();
1153 	sc = gp->softc;
1154 	if (sc == NULL)
1155 		return;
1156 	if (pp != NULL || cp != NULL)
1157 		return;	/* Nothing here. */
1158 
1159 	sbuf_printf(sb, "%s<KeysTotal>%ju</KeysTotal>", indent,
1160 	    (uintmax_t)sc->sc_ekeys_total);
1161 	sbuf_printf(sb, "%s<KeysAllocated>%ju</KeysAllocated>", indent,
1162 	    (uintmax_t)sc->sc_ekeys_allocated);
1163 	sbuf_printf(sb, "%s<Flags>", indent);
1164 	if (sc->sc_flags == 0)
1165 		sbuf_printf(sb, "NONE");
1166 	else {
1167 		int first = 1;
1168 
1169 #define ADD_FLAG(flag, name)	do {					\
1170 	if (sc->sc_flags & (flag)) {					\
1171 		if (!first)						\
1172 			sbuf_printf(sb, ", ");				\
1173 		else							\
1174 			first = 0;					\
1175 		sbuf_printf(sb, name);					\
1176 	}								\
1177 } while (0)
1178 		ADD_FLAG(G_ELI_FLAG_SUSPEND, "SUSPEND");
1179 		ADD_FLAG(G_ELI_FLAG_SINGLE_KEY, "SINGLE-KEY");
1180 		ADD_FLAG(G_ELI_FLAG_NATIVE_BYTE_ORDER, "NATIVE-BYTE-ORDER");
1181 		ADD_FLAG(G_ELI_FLAG_ONETIME, "ONETIME");
1182 		ADD_FLAG(G_ELI_FLAG_BOOT, "BOOT");
1183 		ADD_FLAG(G_ELI_FLAG_WO_DETACH, "W-DETACH");
1184 		ADD_FLAG(G_ELI_FLAG_RW_DETACH, "RW-DETACH");
1185 		ADD_FLAG(G_ELI_FLAG_AUTH, "AUTH");
1186 		ADD_FLAG(G_ELI_FLAG_WOPEN, "W-OPEN");
1187 		ADD_FLAG(G_ELI_FLAG_DESTROY, "DESTROY");
1188 		ADD_FLAG(G_ELI_FLAG_RO, "READ-ONLY");
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<Crypto>", indent);
1198 	switch (sc->sc_crypto) {
1199 	case G_ELI_CRYPTO_HW:
1200 		sbuf_printf(sb, "hardware");
1201 		break;
1202 	case G_ELI_CRYPTO_SW:
1203 		sbuf_printf(sb, "software");
1204 		break;
1205 	default:
1206 		sbuf_printf(sb, "UNKNOWN");
1207 		break;
1208 	}
1209 	sbuf_printf(sb, "</Crypto>\n");
1210 	if (sc->sc_flags & G_ELI_FLAG_AUTH) {
1211 		sbuf_printf(sb,
1212 		    "%s<AuthenticationAlgorithm>%s</AuthenticationAlgorithm>\n",
1213 		    indent, g_eli_algo2str(sc->sc_aalgo));
1214 	}
1215 	sbuf_printf(sb, "%s<KeyLength>%u</KeyLength>\n", indent,
1216 	    sc->sc_ekeylen);
1217 	sbuf_printf(sb, "%s<EncryptionAlgorithm>%s</EncryptionAlgorithm>\n", indent,
1218 	    g_eli_algo2str(sc->sc_ealgo));
1219 	sbuf_printf(sb, "%s<State>%s</State>\n", indent,
1220 	    (sc->sc_flags & G_ELI_FLAG_SUSPEND) ? "SUSPENDED" : "ACTIVE");
1221 }
1222 
1223 static void
1224 g_eli_shutdown_pre_sync(void *arg, int howto)
1225 {
1226 	struct g_class *mp;
1227 	struct g_geom *gp, *gp2;
1228 	struct g_provider *pp;
1229 	struct g_eli_softc *sc;
1230 	int error;
1231 
1232 	mp = arg;
1233 	DROP_GIANT();
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 	PICKUP_GIANT();
1250 }
1251 
1252 static void
1253 g_eli_init(struct g_class *mp)
1254 {
1255 
1256 	g_eli_pre_sync = EVENTHANDLER_REGISTER(shutdown_pre_sync,
1257 	    g_eli_shutdown_pre_sync, mp, SHUTDOWN_PRI_FIRST);
1258 	if (g_eli_pre_sync == NULL)
1259 		G_ELI_DEBUG(0, "Warning! Cannot register shutdown event.");
1260 }
1261 
1262 static void
1263 g_eli_fini(struct g_class *mp)
1264 {
1265 
1266 	if (g_eli_pre_sync != NULL)
1267 		EVENTHANDLER_DEREGISTER(shutdown_pre_sync, g_eli_pre_sync);
1268 }
1269 
1270 DECLARE_GEOM_CLASS(g_eli_class, g_eli);
1271 MODULE_DEPEND(g_eli, crypto, 1, 1, 1);
1272