xref: /freebsd/sys/geom/eli/g_eli.c (revision a0e793cbf1951d07fc47a0d9ea389d7dacba5213)
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 static eventhandler_tag g_eli_pre_sync = NULL;
86 
87 static int g_eli_destroy_geom(struct gctl_req *req, struct g_class *mp,
88     struct g_geom *gp);
89 static void g_eli_init(struct g_class *mp);
90 static void g_eli_fini(struct g_class *mp);
91 
92 static g_taste_t g_eli_taste;
93 static g_dumpconf_t g_eli_dumpconf;
94 
95 struct g_class g_eli_class = {
96 	.name = G_ELI_CLASS_NAME,
97 	.version = G_VERSION,
98 	.ctlreq = g_eli_config,
99 	.taste = g_eli_taste,
100 	.destroy_geom = g_eli_destroy_geom,
101 	.init = g_eli_init,
102 	.fini = g_eli_fini
103 };
104 
105 
106 /*
107  * Code paths:
108  * BIO_READ:
109  *	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
110  * BIO_WRITE:
111  *	g_eli_start -> g_eli_crypto_run -> g_eli_crypto_write_done -> g_io_request -> g_eli_write_done -> g_io_deliver
112  */
113 
114 
115 /*
116  * EAGAIN from crypto(9) means, that we were probably balanced to another crypto
117  * accelerator or something like this.
118  * The function updates the SID and rerun the operation.
119  */
120 int
121 g_eli_crypto_rerun(struct cryptop *crp)
122 {
123 	struct g_eli_softc *sc;
124 	struct g_eli_worker *wr;
125 	struct bio *bp;
126 	int error;
127 
128 	bp = (struct bio *)crp->crp_opaque;
129 	sc = bp->bio_to->geom->softc;
130 	LIST_FOREACH(wr, &sc->sc_workers, w_next) {
131 		if (wr->w_number == bp->bio_pflags)
132 			break;
133 	}
134 	KASSERT(wr != NULL, ("Invalid worker (%u).", bp->bio_pflags));
135 	G_ELI_DEBUG(1, "Rerunning crypto %s request (sid: %ju -> %ju).",
136 	    bp->bio_cmd == BIO_READ ? "READ" : "WRITE", (uintmax_t)wr->w_sid,
137 	    (uintmax_t)crp->crp_sid);
138 	wr->w_sid = crp->crp_sid;
139 	crp->crp_etype = 0;
140 	error = crypto_dispatch(crp);
141 	if (error == 0)
142 		return (0);
143 	G_ELI_DEBUG(1, "%s: crypto_dispatch() returned %d.", __func__, error);
144 	crp->crp_etype = error;
145 	return (error);
146 }
147 
148 /*
149  * The function is called afer reading encrypted data from the provider.
150  *
151  * 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
152  */
153 void
154 g_eli_read_done(struct bio *bp)
155 {
156 	struct g_eli_softc *sc;
157 	struct bio *pbp;
158 
159 	G_ELI_LOGREQ(2, bp, "Request done.");
160 	pbp = bp->bio_parent;
161 	if (pbp->bio_error == 0)
162 		pbp->bio_error = bp->bio_error;
163 	g_destroy_bio(bp);
164 	/*
165 	 * Do we have all sectors already?
166 	 */
167 	pbp->bio_inbed++;
168 	if (pbp->bio_inbed < pbp->bio_children)
169 		return;
170 	sc = pbp->bio_to->geom->softc;
171 	if (pbp->bio_error != 0) {
172 		G_ELI_LOGREQ(0, pbp, "%s() failed", __func__);
173 		pbp->bio_completed = 0;
174 		if (pbp->bio_driver2 != NULL) {
175 			free(pbp->bio_driver2, M_ELI);
176 			pbp->bio_driver2 = NULL;
177 		}
178 		g_io_deliver(pbp, pbp->bio_error);
179 		atomic_subtract_int(&sc->sc_inflight, 1);
180 		return;
181 	}
182 	mtx_lock(&sc->sc_queue_mtx);
183 	bioq_insert_tail(&sc->sc_queue, pbp);
184 	mtx_unlock(&sc->sc_queue_mtx);
185 	wakeup(sc);
186 }
187 
188 /*
189  * The function is called after we encrypt and write data.
190  *
191  * g_eli_start -> g_eli_crypto_run -> g_eli_crypto_write_done -> g_io_request -> G_ELI_WRITE_DONE -> g_io_deliver
192  */
193 void
194 g_eli_write_done(struct bio *bp)
195 {
196 	struct g_eli_softc *sc;
197 	struct bio *pbp;
198 
199 	G_ELI_LOGREQ(2, bp, "Request done.");
200 	pbp = bp->bio_parent;
201 	if (pbp->bio_error == 0) {
202 		if (bp->bio_error != 0)
203 			pbp->bio_error = bp->bio_error;
204 	}
205 	g_destroy_bio(bp);
206 	/*
207 	 * Do we have all sectors already?
208 	 */
209 	pbp->bio_inbed++;
210 	if (pbp->bio_inbed < pbp->bio_children)
211 		return;
212 	free(pbp->bio_driver2, M_ELI);
213 	pbp->bio_driver2 = NULL;
214 	if (pbp->bio_error != 0) {
215 		G_ELI_LOGREQ(0, pbp, "Crypto WRITE request failed (error=%d).",
216 		    pbp->bio_error);
217 		pbp->bio_completed = 0;
218 	}
219 	/*
220 	 * Write is finished, send it up.
221 	 */
222 	pbp->bio_completed = pbp->bio_length;
223 	sc = pbp->bio_to->geom->softc;
224 	g_io_deliver(pbp, pbp->bio_error);
225 	atomic_subtract_int(&sc->sc_inflight, 1);
226 }
227 
228 /*
229  * This function should never be called, but GEOM made as it set ->orphan()
230  * method for every geom.
231  */
232 static void
233 g_eli_orphan_spoil_assert(struct g_consumer *cp)
234 {
235 
236 	panic("Function %s() called for %s.", __func__, cp->geom->name);
237 }
238 
239 static void
240 g_eli_orphan(struct g_consumer *cp)
241 {
242 	struct g_eli_softc *sc;
243 
244 	g_topology_assert();
245 	sc = cp->geom->softc;
246 	if (sc == NULL)
247 		return;
248 	g_eli_destroy(sc, TRUE);
249 }
250 
251 /*
252  * BIO_READ:
253  *	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
254  * BIO_WRITE:
255  *	G_ELI_START -> g_eli_crypto_run -> g_eli_crypto_write_done -> g_io_request -> g_eli_write_done -> g_io_deliver
256  */
257 static void
258 g_eli_start(struct bio *bp)
259 {
260 	struct g_eli_softc *sc;
261 	struct g_consumer *cp;
262 	struct bio *cbp;
263 
264 	sc = bp->bio_to->geom->softc;
265 	KASSERT(sc != NULL,
266 	    ("Provider's error should be set (error=%d)(device=%s).",
267 	    bp->bio_to->error, bp->bio_to->name));
268 	G_ELI_LOGREQ(2, bp, "Request received.");
269 
270 	switch (bp->bio_cmd) {
271 	case BIO_READ:
272 	case BIO_WRITE:
273 	case BIO_GETATTR:
274 	case BIO_FLUSH:
275 		break;
276 	case BIO_DELETE:
277 		/*
278 		 * We could eventually support BIO_DELETE request.
279 		 * It could be done by overwritting requested sector with
280 		 * random data g_eli_overwrites number of times.
281 		 */
282 	default:
283 		g_io_deliver(bp, EOPNOTSUPP);
284 		return;
285 	}
286 	cbp = g_clone_bio(bp);
287 	if (cbp == NULL) {
288 		g_io_deliver(bp, ENOMEM);
289 		return;
290 	}
291 	bp->bio_driver1 = cbp;
292 	bp->bio_pflags = G_ELI_NEW_BIO;
293 	switch (bp->bio_cmd) {
294 	case BIO_READ:
295 		if (!(sc->sc_flags & G_ELI_FLAG_AUTH)) {
296 			g_eli_crypto_read(sc, bp, 0);
297 			break;
298 		}
299 		/* FALLTHROUGH */
300 	case BIO_WRITE:
301 		mtx_lock(&sc->sc_queue_mtx);
302 		bioq_insert_tail(&sc->sc_queue, bp);
303 		mtx_unlock(&sc->sc_queue_mtx);
304 		wakeup(sc);
305 		break;
306 	case BIO_GETATTR:
307 	case BIO_FLUSH:
308 		cbp->bio_done = g_std_done;
309 		cp = LIST_FIRST(&sc->sc_geom->consumer);
310 		cbp->bio_to = cp->provider;
311 		G_ELI_LOGREQ(2, cbp, "Sending request.");
312 		g_io_request(cbp, cp);
313 		break;
314 	}
315 }
316 
317 static int
318 g_eli_newsession(struct g_eli_worker *wr)
319 {
320 	struct g_eli_softc *sc;
321 	struct cryptoini crie, cria;
322 	int error;
323 
324 	sc = wr->w_softc;
325 
326 	bzero(&crie, sizeof(crie));
327 	crie.cri_alg = sc->sc_ealgo;
328 	crie.cri_klen = sc->sc_ekeylen;
329 	if (sc->sc_ealgo == CRYPTO_AES_XTS)
330 		crie.cri_klen <<= 1;
331 	if ((sc->sc_flags & G_ELI_FLAG_FIRST_KEY) != 0) {
332 		crie.cri_key = g_eli_key_hold(sc, 0,
333 		    LIST_FIRST(&sc->sc_geom->consumer)->provider->sectorsize);
334 	} else {
335 		crie.cri_key = sc->sc_ekey;
336 	}
337 	if (sc->sc_flags & G_ELI_FLAG_AUTH) {
338 		bzero(&cria, sizeof(cria));
339 		cria.cri_alg = sc->sc_aalgo;
340 		cria.cri_klen = sc->sc_akeylen;
341 		cria.cri_key = sc->sc_akey;
342 		crie.cri_next = &cria;
343 	}
344 
345 	switch (sc->sc_crypto) {
346 	case G_ELI_CRYPTO_SW:
347 		error = crypto_newsession(&wr->w_sid, &crie,
348 		    CRYPTOCAP_F_SOFTWARE);
349 		break;
350 	case G_ELI_CRYPTO_HW:
351 		error = crypto_newsession(&wr->w_sid, &crie,
352 		    CRYPTOCAP_F_HARDWARE);
353 		break;
354 	case G_ELI_CRYPTO_UNKNOWN:
355 		error = crypto_newsession(&wr->w_sid, &crie,
356 		    CRYPTOCAP_F_HARDWARE);
357 		if (error == 0) {
358 			mtx_lock(&sc->sc_queue_mtx);
359 			if (sc->sc_crypto == G_ELI_CRYPTO_UNKNOWN)
360 				sc->sc_crypto = G_ELI_CRYPTO_HW;
361 			mtx_unlock(&sc->sc_queue_mtx);
362 		} else {
363 			error = crypto_newsession(&wr->w_sid, &crie,
364 			    CRYPTOCAP_F_SOFTWARE);
365 			mtx_lock(&sc->sc_queue_mtx);
366 			if (sc->sc_crypto == G_ELI_CRYPTO_UNKNOWN)
367 				sc->sc_crypto = G_ELI_CRYPTO_SW;
368 			mtx_unlock(&sc->sc_queue_mtx);
369 		}
370 		break;
371 	default:
372 		panic("%s: invalid condition", __func__);
373 	}
374 
375 	if ((sc->sc_flags & G_ELI_FLAG_FIRST_KEY) != 0)
376 		g_eli_key_drop(sc, crie.cri_key);
377 
378 	return (error);
379 }
380 
381 static void
382 g_eli_freesession(struct g_eli_worker *wr)
383 {
384 
385 	crypto_freesession(wr->w_sid);
386 }
387 
388 static void
389 g_eli_cancel(struct g_eli_softc *sc)
390 {
391 	struct bio *bp;
392 
393 	mtx_assert(&sc->sc_queue_mtx, MA_OWNED);
394 
395 	while ((bp = bioq_takefirst(&sc->sc_queue)) != NULL) {
396 		KASSERT(bp->bio_pflags == G_ELI_NEW_BIO,
397 		    ("Not new bio when canceling (bp=%p).", bp));
398 		g_io_deliver(bp, ENXIO);
399 	}
400 }
401 
402 static struct bio *
403 g_eli_takefirst(struct g_eli_softc *sc)
404 {
405 	struct bio *bp;
406 
407 	mtx_assert(&sc->sc_queue_mtx, MA_OWNED);
408 
409 	if (!(sc->sc_flags & G_ELI_FLAG_SUSPEND))
410 		return (bioq_takefirst(&sc->sc_queue));
411 	/*
412 	 * Device suspended, so we skip new I/O requests.
413 	 */
414 	TAILQ_FOREACH(bp, &sc->sc_queue.queue, bio_queue) {
415 		if (bp->bio_pflags != G_ELI_NEW_BIO)
416 			break;
417 	}
418 	if (bp != NULL)
419 		bioq_remove(&sc->sc_queue, bp);
420 	return (bp);
421 }
422 
423 /*
424  * This is the main function for kernel worker thread when we don't have
425  * hardware acceleration and we have to do cryptography in software.
426  * Dedicated thread is needed, so we don't slow down g_up/g_down GEOM
427  * threads with crypto work.
428  */
429 static void
430 g_eli_worker(void *arg)
431 {
432 	struct g_eli_softc *sc;
433 	struct g_eli_worker *wr;
434 	struct bio *bp;
435 	int error;
436 
437 	wr = arg;
438 	sc = wr->w_softc;
439 #ifdef SMP
440 	/* Before sched_bind() to a CPU, wait for all CPUs to go on-line. */
441 	if (sc->sc_cpubind) {
442 		while (!smp_started)
443 			tsleep(wr, 0, "geli:smp", hz / 4);
444 	}
445 #endif
446 	thread_lock(curthread);
447 	sched_prio(curthread, PUSER);
448 	if (sc->sc_cpubind)
449 		sched_bind(curthread, wr->w_number % mp_ncpus);
450 	thread_unlock(curthread);
451 
452 	G_ELI_DEBUG(1, "Thread %s started.", curthread->td_proc->p_comm);
453 
454 	for (;;) {
455 		mtx_lock(&sc->sc_queue_mtx);
456 again:
457 		bp = g_eli_takefirst(sc);
458 		if (bp == NULL) {
459 			if (sc->sc_flags & G_ELI_FLAG_DESTROY) {
460 				g_eli_cancel(sc);
461 				LIST_REMOVE(wr, w_next);
462 				g_eli_freesession(wr);
463 				free(wr, M_ELI);
464 				G_ELI_DEBUG(1, "Thread %s exiting.",
465 				    curthread->td_proc->p_comm);
466 				wakeup(&sc->sc_workers);
467 				mtx_unlock(&sc->sc_queue_mtx);
468 				kproc_exit(0);
469 			}
470 			while (sc->sc_flags & G_ELI_FLAG_SUSPEND) {
471 				if (sc->sc_inflight > 0) {
472 					G_ELI_DEBUG(0, "inflight=%d",
473 					    sc->sc_inflight);
474 					/*
475 					 * We still have inflight BIOs, so
476 					 * sleep and retry.
477 					 */
478 					msleep(sc, &sc->sc_queue_mtx, PRIBIO,
479 					    "geli:inf", hz / 5);
480 					goto again;
481 				}
482 				/*
483 				 * Suspend requested, mark the worker as
484 				 * suspended and go to sleep.
485 				 */
486 				if (wr->w_active) {
487 					g_eli_freesession(wr);
488 					wr->w_active = FALSE;
489 				}
490 				wakeup(&sc->sc_workers);
491 				msleep(sc, &sc->sc_queue_mtx, PRIBIO,
492 				    "geli:suspend", 0);
493 				if (!wr->w_active &&
494 				    !(sc->sc_flags & G_ELI_FLAG_SUSPEND)) {
495 					error = g_eli_newsession(wr);
496 					KASSERT(error == 0,
497 					    ("g_eli_newsession() failed on resume (error=%d)",
498 					    error));
499 					wr->w_active = TRUE;
500 				}
501 				goto again;
502 			}
503 			msleep(sc, &sc->sc_queue_mtx, PDROP, "geli:w", 0);
504 			continue;
505 		}
506 		if (bp->bio_pflags == G_ELI_NEW_BIO)
507 			atomic_add_int(&sc->sc_inflight, 1);
508 		mtx_unlock(&sc->sc_queue_mtx);
509 		if (bp->bio_pflags == G_ELI_NEW_BIO) {
510 			bp->bio_pflags = 0;
511 			if (sc->sc_flags & G_ELI_FLAG_AUTH) {
512 				if (bp->bio_cmd == BIO_READ)
513 					g_eli_auth_read(sc, bp);
514 				else
515 					g_eli_auth_run(wr, bp);
516 			} else {
517 				if (bp->bio_cmd == BIO_READ)
518 					g_eli_crypto_read(sc, bp, 1);
519 				else
520 					g_eli_crypto_run(wr, bp);
521 			}
522 		} else {
523 			if (sc->sc_flags & G_ELI_FLAG_AUTH)
524 				g_eli_auth_run(wr, bp);
525 			else
526 				g_eli_crypto_run(wr, bp);
527 		}
528 	}
529 }
530 
531 /*
532  * Here we generate IV. It is unique for every sector.
533  */
534 void
535 g_eli_crypto_ivgen(struct g_eli_softc *sc, off_t offset, u_char *iv,
536     size_t size)
537 {
538 	uint8_t off[8];
539 
540 	if ((sc->sc_flags & G_ELI_FLAG_NATIVE_BYTE_ORDER) != 0)
541 		bcopy(&offset, off, sizeof(off));
542 	else
543 		le64enc(off, (uint64_t)offset);
544 
545 	switch (sc->sc_ealgo) {
546 	case CRYPTO_AES_XTS:
547 		bcopy(off, iv, sizeof(off));
548 		bzero(iv + sizeof(off), size - sizeof(off));
549 		break;
550 	default:
551 	    {
552 		u_char hash[SHA256_DIGEST_LENGTH];
553 		SHA256_CTX ctx;
554 
555 		/* Copy precalculated SHA256 context for IV-Key. */
556 		bcopy(&sc->sc_ivctx, &ctx, sizeof(ctx));
557 		SHA256_Update(&ctx, off, sizeof(off));
558 		SHA256_Final(hash, &ctx);
559 		bcopy(hash, iv, MIN(sizeof(hash), size));
560 		break;
561 	    }
562 	}
563 }
564 
565 int
566 g_eli_read_metadata(struct g_class *mp, struct g_provider *pp,
567     struct g_eli_metadata *md)
568 {
569 	struct g_geom *gp;
570 	struct g_consumer *cp;
571 	u_char *buf = NULL;
572 	int error;
573 
574 	g_topology_assert();
575 
576 	gp = g_new_geomf(mp, "eli:taste");
577 	gp->start = g_eli_start;
578 	gp->access = g_std_access;
579 	/*
580 	 * g_eli_read_metadata() is always called from the event thread.
581 	 * Our geom is created and destroyed in the same event, so there
582 	 * could be no orphan nor spoil event in the meantime.
583 	 */
584 	gp->orphan = g_eli_orphan_spoil_assert;
585 	gp->spoiled = g_eli_orphan_spoil_assert;
586 	cp = g_new_consumer(gp);
587 	error = g_attach(cp, pp);
588 	if (error != 0)
589 		goto end;
590 	error = g_access(cp, 1, 0, 0);
591 	if (error != 0)
592 		goto end;
593 	g_topology_unlock();
594 	buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
595 	    &error);
596 	g_topology_lock();
597 	if (buf == NULL)
598 		goto end;
599 	eli_metadata_decode(buf, md);
600 end:
601 	if (buf != NULL)
602 		g_free(buf);
603 	if (cp->provider != NULL) {
604 		if (cp->acr == 1)
605 			g_access(cp, -1, 0, 0);
606 		g_detach(cp);
607 	}
608 	g_destroy_consumer(cp);
609 	g_destroy_geom(gp);
610 	return (error);
611 }
612 
613 /*
614  * The function is called when we had last close on provider and user requested
615  * to close it when this situation occur.
616  */
617 static void
618 g_eli_last_close(void *arg, int flags __unused)
619 {
620 	struct g_geom *gp;
621 	char gpname[64];
622 	int error;
623 
624 	g_topology_assert();
625 	gp = arg;
626 	strlcpy(gpname, gp->name, sizeof(gpname));
627 	error = g_eli_destroy(gp->softc, TRUE);
628 	KASSERT(error == 0, ("Cannot detach %s on last close (error=%d).",
629 	    gpname, error));
630 	G_ELI_DEBUG(0, "Detached %s on last close.", gpname);
631 }
632 
633 int
634 g_eli_access(struct g_provider *pp, int dr, int dw, int de)
635 {
636 	struct g_eli_softc *sc;
637 	struct g_geom *gp;
638 
639 	gp = pp->geom;
640 	sc = gp->softc;
641 
642 	if (dw > 0) {
643 		if (sc->sc_flags & G_ELI_FLAG_RO) {
644 			/* Deny write attempts. */
645 			return (EROFS);
646 		}
647 		/* Someone is opening us for write, we need to remember that. */
648 		sc->sc_flags |= G_ELI_FLAG_WOPEN;
649 		return (0);
650 	}
651 	/* Is this the last close? */
652 	if (pp->acr + dr > 0 || pp->acw + dw > 0 || pp->ace + de > 0)
653 		return (0);
654 
655 	/*
656 	 * Automatically detach on last close if requested.
657 	 */
658 	if ((sc->sc_flags & G_ELI_FLAG_RW_DETACH) ||
659 	    (sc->sc_flags & G_ELI_FLAG_WOPEN)) {
660 		g_post_event(g_eli_last_close, gp, M_WAITOK, NULL);
661 	}
662 	return (0);
663 }
664 
665 static int
666 g_eli_cpu_is_disabled(int cpu)
667 {
668 #ifdef SMP
669 	return (CPU_ISSET(cpu, &hlt_cpus_mask));
670 #else
671 	return (0);
672 #endif
673 }
674 
675 struct g_geom *
676 g_eli_create(struct gctl_req *req, struct g_class *mp, struct g_provider *bpp,
677     const struct g_eli_metadata *md, const u_char *mkey, int nkey)
678 {
679 	struct g_eli_softc *sc;
680 	struct g_eli_worker *wr;
681 	struct g_geom *gp;
682 	struct g_provider *pp;
683 	struct g_consumer *cp;
684 	u_int i, threads;
685 	int error;
686 
687 	G_ELI_DEBUG(1, "Creating device %s%s.", bpp->name, G_ELI_SUFFIX);
688 
689 	gp = g_new_geomf(mp, "%s%s", bpp->name, G_ELI_SUFFIX);
690 	sc = malloc(sizeof(*sc), M_ELI, M_WAITOK | M_ZERO);
691 	gp->start = g_eli_start;
692 	/*
693 	 * Spoiling cannot happen actually, because we keep provider open for
694 	 * writing all the time or provider is read-only.
695 	 */
696 	gp->spoiled = g_eli_orphan_spoil_assert;
697 	gp->orphan = g_eli_orphan;
698 	gp->dumpconf = g_eli_dumpconf;
699 	/*
700 	 * If detach-on-last-close feature is not enabled and we don't operate
701 	 * on read-only provider, we can simply use g_std_access().
702 	 */
703 	if (md->md_flags & (G_ELI_FLAG_WO_DETACH | G_ELI_FLAG_RO))
704 		gp->access = g_eli_access;
705 	else
706 		gp->access = g_std_access;
707 
708 	sc->sc_version = md->md_version;
709 	sc->sc_inflight = 0;
710 	sc->sc_crypto = G_ELI_CRYPTO_UNKNOWN;
711 	sc->sc_flags = md->md_flags;
712 	/* Backward compatibility. */
713 	if (md->md_version < G_ELI_VERSION_04)
714 		sc->sc_flags |= G_ELI_FLAG_NATIVE_BYTE_ORDER;
715 	if (md->md_version < G_ELI_VERSION_05)
716 		sc->sc_flags |= G_ELI_FLAG_SINGLE_KEY;
717 	if (md->md_version < G_ELI_VERSION_06 &&
718 	    (sc->sc_flags & G_ELI_FLAG_AUTH) != 0) {
719 		sc->sc_flags |= G_ELI_FLAG_FIRST_KEY;
720 	}
721 	if (md->md_version < G_ELI_VERSION_07)
722 		sc->sc_flags |= G_ELI_FLAG_ENC_IVKEY;
723 	sc->sc_ealgo = md->md_ealgo;
724 	sc->sc_nkey = nkey;
725 
726 	if (sc->sc_flags & G_ELI_FLAG_AUTH) {
727 		sc->sc_akeylen = sizeof(sc->sc_akey) * 8;
728 		sc->sc_aalgo = md->md_aalgo;
729 		sc->sc_alen = g_eli_hashlen(sc->sc_aalgo);
730 
731 		sc->sc_data_per_sector = bpp->sectorsize - sc->sc_alen;
732 		/*
733 		 * Some hash functions (like SHA1 and RIPEMD160) generates hash
734 		 * which length is not multiple of 128 bits, but we want data
735 		 * length to be multiple of 128, so we can encrypt without
736 		 * padding. The line below rounds down data length to multiple
737 		 * of 128 bits.
738 		 */
739 		sc->sc_data_per_sector -= sc->sc_data_per_sector % 16;
740 
741 		sc->sc_bytes_per_sector =
742 		    (md->md_sectorsize - 1) / sc->sc_data_per_sector + 1;
743 		sc->sc_bytes_per_sector *= bpp->sectorsize;
744 	}
745 
746 	gp->softc = sc;
747 	sc->sc_geom = gp;
748 
749 	bioq_init(&sc->sc_queue);
750 	mtx_init(&sc->sc_queue_mtx, "geli:queue", NULL, MTX_DEF);
751 	mtx_init(&sc->sc_ekeys_lock, "geli:ekeys", NULL, MTX_DEF);
752 
753 	pp = NULL;
754 	cp = g_new_consumer(gp);
755 	error = g_attach(cp, bpp);
756 	if (error != 0) {
757 		if (req != NULL) {
758 			gctl_error(req, "Cannot attach to %s (error=%d).",
759 			    bpp->name, error);
760 		} else {
761 			G_ELI_DEBUG(1, "Cannot attach to %s (error=%d).",
762 			    bpp->name, error);
763 		}
764 		goto failed;
765 	}
766 	/*
767 	 * Keep provider open all the time, so we can run critical tasks,
768 	 * like Master Keys deletion, without wondering if we can open
769 	 * provider or not.
770 	 * We don't open provider for writing only when user requested read-only
771 	 * access.
772 	 */
773 	if (sc->sc_flags & G_ELI_FLAG_RO)
774 		error = g_access(cp, 1, 0, 1);
775 	else
776 		error = g_access(cp, 1, 1, 1);
777 	if (error != 0) {
778 		if (req != NULL) {
779 			gctl_error(req, "Cannot access %s (error=%d).",
780 			    bpp->name, error);
781 		} else {
782 			G_ELI_DEBUG(1, "Cannot access %s (error=%d).",
783 			    bpp->name, error);
784 		}
785 		goto failed;
786 	}
787 
788 	sc->sc_sectorsize = md->md_sectorsize;
789 	sc->sc_mediasize = bpp->mediasize;
790 	if (!(sc->sc_flags & G_ELI_FLAG_ONETIME))
791 		sc->sc_mediasize -= bpp->sectorsize;
792 	if (!(sc->sc_flags & G_ELI_FLAG_AUTH))
793 		sc->sc_mediasize -= (sc->sc_mediasize % sc->sc_sectorsize);
794 	else {
795 		sc->sc_mediasize /= sc->sc_bytes_per_sector;
796 		sc->sc_mediasize *= sc->sc_sectorsize;
797 	}
798 
799 	/*
800 	 * Remember the keys in our softc structure.
801 	 */
802 	g_eli_mkey_propagate(sc, mkey);
803 	sc->sc_ekeylen = md->md_keylen;
804 
805 	LIST_INIT(&sc->sc_workers);
806 
807 	threads = g_eli_threads;
808 	if (threads == 0)
809 		threads = mp_ncpus;
810 	sc->sc_cpubind = (mp_ncpus > 1 && threads == mp_ncpus);
811 	for (i = 0; i < threads; i++) {
812 		if (g_eli_cpu_is_disabled(i)) {
813 			G_ELI_DEBUG(1, "%s: CPU %u disabled, skipping.",
814 			    bpp->name, i);
815 			continue;
816 		}
817 		wr = malloc(sizeof(*wr), M_ELI, M_WAITOK | M_ZERO);
818 		wr->w_softc = sc;
819 		wr->w_number = i;
820 		wr->w_active = TRUE;
821 
822 		error = g_eli_newsession(wr);
823 		if (error != 0) {
824 			free(wr, M_ELI);
825 			if (req != NULL) {
826 				gctl_error(req, "Cannot set up crypto session "
827 				    "for %s (error=%d).", bpp->name, error);
828 			} else {
829 				G_ELI_DEBUG(1, "Cannot set up crypto session "
830 				    "for %s (error=%d).", bpp->name, error);
831 			}
832 			goto failed;
833 		}
834 
835 		error = kproc_create(g_eli_worker, wr, &wr->w_proc, 0, 0,
836 		    "g_eli[%u] %s", i, bpp->name);
837 		if (error != 0) {
838 			g_eli_freesession(wr);
839 			free(wr, M_ELI);
840 			if (req != NULL) {
841 				gctl_error(req, "Cannot create kernel thread "
842 				    "for %s (error=%d).", bpp->name, error);
843 			} else {
844 				G_ELI_DEBUG(1, "Cannot create kernel thread "
845 				    "for %s (error=%d).", bpp->name, error);
846 			}
847 			goto failed;
848 		}
849 		LIST_INSERT_HEAD(&sc->sc_workers, wr, w_next);
850 	}
851 
852 	/*
853 	 * Create decrypted provider.
854 	 */
855 	pp = g_new_providerf(gp, "%s%s", bpp->name, G_ELI_SUFFIX);
856 	pp->mediasize = sc->sc_mediasize;
857 	pp->sectorsize = sc->sc_sectorsize;
858 
859 	g_error_provider(pp, 0);
860 
861 	G_ELI_DEBUG(0, "Device %s created.", pp->name);
862 	G_ELI_DEBUG(0, "Encryption: %s %u", g_eli_algo2str(sc->sc_ealgo),
863 	    sc->sc_ekeylen);
864 	if (sc->sc_flags & G_ELI_FLAG_AUTH)
865 		G_ELI_DEBUG(0, " Integrity: %s", g_eli_algo2str(sc->sc_aalgo));
866 	G_ELI_DEBUG(0, "    Crypto: %s",
867 	    sc->sc_crypto == G_ELI_CRYPTO_SW ? "software" : "hardware");
868 	return (gp);
869 failed:
870 	mtx_lock(&sc->sc_queue_mtx);
871 	sc->sc_flags |= G_ELI_FLAG_DESTROY;
872 	wakeup(sc);
873 	/*
874 	 * Wait for kernel threads self destruction.
875 	 */
876 	while (!LIST_EMPTY(&sc->sc_workers)) {
877 		msleep(&sc->sc_workers, &sc->sc_queue_mtx, PRIBIO,
878 		    "geli:destroy", 0);
879 	}
880 	mtx_destroy(&sc->sc_queue_mtx);
881 	if (cp->provider != NULL) {
882 		if (cp->acr == 1)
883 			g_access(cp, -1, -1, -1);
884 		g_detach(cp);
885 	}
886 	g_destroy_consumer(cp);
887 	g_destroy_geom(gp);
888 	g_eli_key_destroy(sc);
889 	bzero(sc, sizeof(*sc));
890 	free(sc, M_ELI);
891 	return (NULL);
892 }
893 
894 int
895 g_eli_destroy(struct g_eli_softc *sc, boolean_t force)
896 {
897 	struct g_geom *gp;
898 	struct g_provider *pp;
899 
900 	g_topology_assert();
901 
902 	if (sc == NULL)
903 		return (ENXIO);
904 
905 	gp = sc->sc_geom;
906 	pp = LIST_FIRST(&gp->provider);
907 	if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) {
908 		if (force) {
909 			G_ELI_DEBUG(1, "Device %s is still open, so it "
910 			    "cannot be definitely removed.", pp->name);
911 			sc->sc_flags |= G_ELI_FLAG_RW_DETACH;
912 			gp->access = g_eli_access;
913 			g_wither_provider(pp, ENXIO);
914 			return (EBUSY);
915 		} else {
916 			G_ELI_DEBUG(1,
917 			    "Device %s is still open (r%dw%de%d).", pp->name,
918 			    pp->acr, pp->acw, pp->ace);
919 			return (EBUSY);
920 		}
921 	}
922 
923 	mtx_lock(&sc->sc_queue_mtx);
924 	sc->sc_flags |= G_ELI_FLAG_DESTROY;
925 	wakeup(sc);
926 	while (!LIST_EMPTY(&sc->sc_workers)) {
927 		msleep(&sc->sc_workers, &sc->sc_queue_mtx, PRIBIO,
928 		    "geli:destroy", 0);
929 	}
930 	mtx_destroy(&sc->sc_queue_mtx);
931 	gp->softc = NULL;
932 	g_eli_key_destroy(sc);
933 	bzero(sc, sizeof(*sc));
934 	free(sc, M_ELI);
935 
936 	if (pp == NULL || (pp->acr == 0 && pp->acw == 0 && pp->ace == 0))
937 		G_ELI_DEBUG(0, "Device %s destroyed.", gp->name);
938 	g_wither_geom_close(gp, ENXIO);
939 
940 	return (0);
941 }
942 
943 static int
944 g_eli_destroy_geom(struct gctl_req *req __unused,
945     struct g_class *mp __unused, struct g_geom *gp)
946 {
947 	struct g_eli_softc *sc;
948 
949 	sc = gp->softc;
950 	return (g_eli_destroy(sc, FALSE));
951 }
952 
953 static int
954 g_eli_keyfiles_load(struct hmac_ctx *ctx, const char *provider)
955 {
956 	u_char *keyfile, *data;
957 	char *file, name[64];
958 	size_t size;
959 	int i;
960 
961 	for (i = 0; ; i++) {
962 		snprintf(name, sizeof(name), "%s:geli_keyfile%d", provider, i);
963 		keyfile = preload_search_by_type(name);
964 		if (keyfile == NULL)
965 			return (i);	/* Return number of loaded keyfiles. */
966 		data = preload_fetch_addr(keyfile);
967 		if (data == NULL) {
968 			G_ELI_DEBUG(0, "Cannot find key file data for %s.",
969 			    name);
970 			return (0);
971 		}
972 		size = preload_fetch_size(keyfile);
973 		if (size == 0) {
974 			G_ELI_DEBUG(0, "Cannot find key file size for %s.",
975 			    name);
976 			return (0);
977 		}
978 		file = preload_search_info(keyfile, MODINFO_NAME);
979 		if (file == NULL) {
980 			G_ELI_DEBUG(0, "Cannot find key file name for %s.",
981 			    name);
982 			return (0);
983 		}
984 		G_ELI_DEBUG(1, "Loaded keyfile %s for %s (type: %s).", file,
985 		    provider, name);
986 		g_eli_crypto_hmac_update(ctx, data, size);
987 	}
988 }
989 
990 static void
991 g_eli_keyfiles_clear(const char *provider)
992 {
993 	u_char *keyfile, *data;
994 	char name[64];
995 	size_t size;
996 	int i;
997 
998 	for (i = 0; ; i++) {
999 		snprintf(name, sizeof(name), "%s:geli_keyfile%d", provider, i);
1000 		keyfile = preload_search_by_type(name);
1001 		if (keyfile == NULL)
1002 			return;
1003 		data = preload_fetch_addr(keyfile);
1004 		size = preload_fetch_size(keyfile);
1005 		if (data != NULL && size != 0)
1006 			bzero(data, size);
1007 	}
1008 }
1009 
1010 /*
1011  * Tasting is only made on boot.
1012  * We detect providers which should be attached before root is mounted.
1013  */
1014 static struct g_geom *
1015 g_eli_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
1016 {
1017 	struct g_eli_metadata md;
1018 	struct g_geom *gp;
1019 	struct hmac_ctx ctx;
1020 	char passphrase[256];
1021 	u_char key[G_ELI_USERKEYLEN], mkey[G_ELI_DATAIVKEYLEN];
1022 	u_int i, nkey, nkeyfiles, tries;
1023 	int error;
1024 
1025 	g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
1026 	g_topology_assert();
1027 
1028 	if (root_mounted() || g_eli_tries == 0)
1029 		return (NULL);
1030 
1031 	G_ELI_DEBUG(3, "Tasting %s.", pp->name);
1032 
1033 	error = g_eli_read_metadata(mp, pp, &md);
1034 	if (error != 0)
1035 		return (NULL);
1036 	gp = NULL;
1037 
1038 	if (strcmp(md.md_magic, G_ELI_MAGIC) != 0)
1039 		return (NULL);
1040 	if (md.md_version > G_ELI_VERSION) {
1041 		printf("geom_eli.ko module is too old to handle %s.\n",
1042 		    pp->name);
1043 		return (NULL);
1044 	}
1045 	if (md.md_provsize != pp->mediasize)
1046 		return (NULL);
1047 	/* Should we attach it on boot? */
1048 	if (!(md.md_flags & G_ELI_FLAG_BOOT))
1049 		return (NULL);
1050 	if (md.md_keys == 0x00) {
1051 		G_ELI_DEBUG(0, "No valid keys on %s.", pp->name);
1052 		return (NULL);
1053 	}
1054 	if (md.md_iterations == -1) {
1055 		/* If there is no passphrase, we try only once. */
1056 		tries = 1;
1057 	} else {
1058 		/* Ask for the passphrase no more than g_eli_tries times. */
1059 		tries = g_eli_tries;
1060 	}
1061 
1062 	for (i = 0; i < tries; i++) {
1063 		g_eli_crypto_hmac_init(&ctx, NULL, 0);
1064 
1065 		/*
1066 		 * Load all key files.
1067 		 */
1068 		nkeyfiles = g_eli_keyfiles_load(&ctx, pp->name);
1069 
1070 		if (nkeyfiles == 0 && md.md_iterations == -1) {
1071 			/*
1072 			 * No key files and no passphrase, something is
1073 			 * definitely wrong here.
1074 			 * geli(8) doesn't allow for such situation, so assume
1075 			 * that there was really no passphrase and in that case
1076 			 * key files are no properly defined in loader.conf.
1077 			 */
1078 			G_ELI_DEBUG(0,
1079 			    "Found no key files in loader.conf for %s.",
1080 			    pp->name);
1081 			return (NULL);
1082 		}
1083 
1084 		/* Ask for the passphrase if defined. */
1085 		if (md.md_iterations >= 0) {
1086 			printf("Enter passphrase for %s: ", pp->name);
1087 			cngets(passphrase, sizeof(passphrase),
1088 			    g_eli_visible_passphrase);
1089 		}
1090 
1091 		/*
1092 		 * Prepare Derived-Key from the user passphrase.
1093 		 */
1094 		if (md.md_iterations == 0) {
1095 			g_eli_crypto_hmac_update(&ctx, md.md_salt,
1096 			    sizeof(md.md_salt));
1097 			g_eli_crypto_hmac_update(&ctx, passphrase,
1098 			    strlen(passphrase));
1099 			bzero(passphrase, sizeof(passphrase));
1100 		} else if (md.md_iterations > 0) {
1101 			u_char dkey[G_ELI_USERKEYLEN];
1102 
1103 			pkcs5v2_genkey(dkey, sizeof(dkey), md.md_salt,
1104 			    sizeof(md.md_salt), passphrase, md.md_iterations);
1105 			bzero(passphrase, sizeof(passphrase));
1106 			g_eli_crypto_hmac_update(&ctx, dkey, sizeof(dkey));
1107 			bzero(dkey, sizeof(dkey));
1108 		}
1109 
1110 		g_eli_crypto_hmac_final(&ctx, key, 0);
1111 
1112 		/*
1113 		 * Decrypt Master-Key.
1114 		 */
1115 		error = g_eli_mkey_decrypt(&md, key, mkey, &nkey);
1116 		bzero(key, sizeof(key));
1117 		if (error == -1) {
1118 			if (i == tries - 1) {
1119 				G_ELI_DEBUG(0,
1120 				    "Wrong key for %s. No tries left.",
1121 				    pp->name);
1122 				g_eli_keyfiles_clear(pp->name);
1123 				return (NULL);
1124 			}
1125 			G_ELI_DEBUG(0, "Wrong key for %s. Tries left: %u.",
1126 			    pp->name, tries - i - 1);
1127 			/* Try again. */
1128 			continue;
1129 		} else if (error > 0) {
1130 			G_ELI_DEBUG(0,
1131 			    "Cannot decrypt Master Key for %s (error=%d).",
1132 			    pp->name, error);
1133 			g_eli_keyfiles_clear(pp->name);
1134 			return (NULL);
1135 		}
1136 		g_eli_keyfiles_clear(pp->name);
1137 		G_ELI_DEBUG(1, "Using Master Key %u for %s.", nkey, pp->name);
1138 		break;
1139 	}
1140 
1141 	/*
1142 	 * We have correct key, let's attach provider.
1143 	 */
1144 	gp = g_eli_create(NULL, mp, pp, &md, mkey, nkey);
1145 	bzero(mkey, sizeof(mkey));
1146 	bzero(&md, sizeof(md));
1147 	if (gp == NULL) {
1148 		G_ELI_DEBUG(0, "Cannot create device %s%s.", pp->name,
1149 		    G_ELI_SUFFIX);
1150 		return (NULL);
1151 	}
1152 	return (gp);
1153 }
1154 
1155 static void
1156 g_eli_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
1157     struct g_consumer *cp, struct g_provider *pp)
1158 {
1159 	struct g_eli_softc *sc;
1160 
1161 	g_topology_assert();
1162 	sc = gp->softc;
1163 	if (sc == NULL)
1164 		return;
1165 	if (pp != NULL || cp != NULL)
1166 		return;	/* Nothing here. */
1167 
1168 	sbuf_printf(sb, "%s<KeysTotal>%ju</KeysTotal>\n", indent,
1169 	    (uintmax_t)sc->sc_ekeys_total);
1170 	sbuf_printf(sb, "%s<KeysAllocated>%ju</KeysAllocated>\n", indent,
1171 	    (uintmax_t)sc->sc_ekeys_allocated);
1172 	sbuf_printf(sb, "%s<Flags>", indent);
1173 	if (sc->sc_flags == 0)
1174 		sbuf_printf(sb, "NONE");
1175 	else {
1176 		int first = 1;
1177 
1178 #define ADD_FLAG(flag, name)	do {					\
1179 	if (sc->sc_flags & (flag)) {					\
1180 		if (!first)						\
1181 			sbuf_printf(sb, ", ");				\
1182 		else							\
1183 			first = 0;					\
1184 		sbuf_printf(sb, name);					\
1185 	}								\
1186 } while (0)
1187 		ADD_FLAG(G_ELI_FLAG_SUSPEND, "SUSPEND");
1188 		ADD_FLAG(G_ELI_FLAG_SINGLE_KEY, "SINGLE-KEY");
1189 		ADD_FLAG(G_ELI_FLAG_NATIVE_BYTE_ORDER, "NATIVE-BYTE-ORDER");
1190 		ADD_FLAG(G_ELI_FLAG_ONETIME, "ONETIME");
1191 		ADD_FLAG(G_ELI_FLAG_BOOT, "BOOT");
1192 		ADD_FLAG(G_ELI_FLAG_WO_DETACH, "W-DETACH");
1193 		ADD_FLAG(G_ELI_FLAG_RW_DETACH, "RW-DETACH");
1194 		ADD_FLAG(G_ELI_FLAG_AUTH, "AUTH");
1195 		ADD_FLAG(G_ELI_FLAG_WOPEN, "W-OPEN");
1196 		ADD_FLAG(G_ELI_FLAG_DESTROY, "DESTROY");
1197 		ADD_FLAG(G_ELI_FLAG_RO, "READ-ONLY");
1198 #undef  ADD_FLAG
1199 	}
1200 	sbuf_printf(sb, "</Flags>\n");
1201 
1202 	if (!(sc->sc_flags & G_ELI_FLAG_ONETIME)) {
1203 		sbuf_printf(sb, "%s<UsedKey>%u</UsedKey>\n", indent,
1204 		    sc->sc_nkey);
1205 	}
1206 	sbuf_printf(sb, "%s<Version>%u</Version>\n", indent, sc->sc_version);
1207 	sbuf_printf(sb, "%s<Crypto>", indent);
1208 	switch (sc->sc_crypto) {
1209 	case G_ELI_CRYPTO_HW:
1210 		sbuf_printf(sb, "hardware");
1211 		break;
1212 	case G_ELI_CRYPTO_SW:
1213 		sbuf_printf(sb, "software");
1214 		break;
1215 	default:
1216 		sbuf_printf(sb, "UNKNOWN");
1217 		break;
1218 	}
1219 	sbuf_printf(sb, "</Crypto>\n");
1220 	if (sc->sc_flags & G_ELI_FLAG_AUTH) {
1221 		sbuf_printf(sb,
1222 		    "%s<AuthenticationAlgorithm>%s</AuthenticationAlgorithm>\n",
1223 		    indent, g_eli_algo2str(sc->sc_aalgo));
1224 	}
1225 	sbuf_printf(sb, "%s<KeyLength>%u</KeyLength>\n", indent,
1226 	    sc->sc_ekeylen);
1227 	sbuf_printf(sb, "%s<EncryptionAlgorithm>%s</EncryptionAlgorithm>\n",
1228 	    indent, g_eli_algo2str(sc->sc_ealgo));
1229 	sbuf_printf(sb, "%s<State>%s</State>\n", indent,
1230 	    (sc->sc_flags & G_ELI_FLAG_SUSPEND) ? "SUSPENDED" : "ACTIVE");
1231 }
1232 
1233 static void
1234 g_eli_shutdown_pre_sync(void *arg, int howto)
1235 {
1236 	struct g_class *mp;
1237 	struct g_geom *gp, *gp2;
1238 	struct g_provider *pp;
1239 	struct g_eli_softc *sc;
1240 	int error;
1241 
1242 	mp = arg;
1243 	DROP_GIANT();
1244 	g_topology_lock();
1245 	LIST_FOREACH_SAFE(gp, &mp->geom, geom, gp2) {
1246 		sc = gp->softc;
1247 		if (sc == NULL)
1248 			continue;
1249 		pp = LIST_FIRST(&gp->provider);
1250 		KASSERT(pp != NULL, ("No provider? gp=%p (%s)", gp, gp->name));
1251 		if (pp->acr + pp->acw + pp->ace == 0)
1252 			error = g_eli_destroy(sc, TRUE);
1253 		else {
1254 			sc->sc_flags |= G_ELI_FLAG_RW_DETACH;
1255 			gp->access = g_eli_access;
1256 		}
1257 	}
1258 	g_topology_unlock();
1259 	PICKUP_GIANT();
1260 }
1261 
1262 static void
1263 g_eli_init(struct g_class *mp)
1264 {
1265 
1266 	g_eli_pre_sync = EVENTHANDLER_REGISTER(shutdown_pre_sync,
1267 	    g_eli_shutdown_pre_sync, mp, SHUTDOWN_PRI_FIRST);
1268 	if (g_eli_pre_sync == NULL)
1269 		G_ELI_DEBUG(0, "Warning! Cannot register shutdown event.");
1270 }
1271 
1272 static void
1273 g_eli_fini(struct g_class *mp)
1274 {
1275 
1276 	if (g_eli_pre_sync != NULL)
1277 		EVENTHANDLER_DEREGISTER(shutdown_pre_sync, g_eli_pre_sync);
1278 }
1279 
1280 DECLARE_GEOM_CLASS(g_eli_class, g_eli);
1281 MODULE_DEPEND(g_eli, crypto, 1, 1, 1);
1282