xref: /freebsd/sys/crypto/aesni/aesni.c (revision d6b92ffa)
1 /*-
2  * Copyright (c) 2005-2008 Pawel Jakub Dawidek <pjd@FreeBSD.org>
3  * Copyright (c) 2010 Konstantin Belousov <kib@FreeBSD.org>
4  * Copyright (c) 2014 The FreeBSD Foundation
5  * All rights reserved.
6  *
7  * Portions of this software were developed by John-Mark Gurney
8  * under sponsorship of the FreeBSD Foundation and
9  * Rubicon Communications, LLC (Netgate).
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/kernel.h>
39 #include <sys/kobj.h>
40 #include <sys/libkern.h>
41 #include <sys/lock.h>
42 #include <sys/module.h>
43 #include <sys/malloc.h>
44 #include <sys/rwlock.h>
45 #include <sys/bus.h>
46 #include <sys/uio.h>
47 #include <sys/mbuf.h>
48 #include <sys/smp.h>
49 #include <crypto/aesni/aesni.h>
50 #include <cryptodev_if.h>
51 #include <opencrypto/gmac.h>
52 
53 static struct mtx_padalign *ctx_mtx;
54 static struct fpu_kern_ctx **ctx_fpu;
55 
56 struct aesni_softc {
57 	int	dieing;
58 	int32_t cid;
59 	uint32_t sid;
60 	TAILQ_HEAD(aesni_sessions_head, aesni_session) sessions;
61 	struct rwlock lock;
62 };
63 
64 #define AQUIRE_CTX(i, ctx)					\
65 	do {							\
66 		(i) = PCPU_GET(cpuid);				\
67 		mtx_lock(&ctx_mtx[(i)]);			\
68 		(ctx) = ctx_fpu[(i)];				\
69 	} while (0)
70 #define RELEASE_CTX(i, ctx)					\
71 	do {							\
72 		mtx_unlock(&ctx_mtx[(i)]);			\
73 		(i) = -1;					\
74 		(ctx) = NULL;					\
75 	} while (0)
76 
77 static int aesni_newsession(device_t, uint32_t *sidp, struct cryptoini *cri);
78 static int aesni_freesession(device_t, uint64_t tid);
79 static void aesni_freesession_locked(struct aesni_softc *sc,
80     struct aesni_session *ses);
81 static int aesni_cipher_setup(struct aesni_session *ses,
82     struct cryptoini *encini);
83 static int aesni_cipher_process(struct aesni_session *ses,
84     struct cryptodesc *enccrd, struct cryptodesc *authcrd, struct cryptop *crp);
85 
86 MALLOC_DEFINE(M_AESNI, "aesni_data", "AESNI Data");
87 
88 static void
89 aesni_identify(driver_t *drv, device_t parent)
90 {
91 
92 	/* NB: order 10 is so we get attached after h/w devices */
93 	if (device_find_child(parent, "aesni", -1) == NULL &&
94 	    BUS_ADD_CHILD(parent, 10, "aesni", -1) == 0)
95 		panic("aesni: could not attach");
96 }
97 
98 static int
99 aesni_probe(device_t dev)
100 {
101 
102 	if ((cpu_feature2 & CPUID2_AESNI) == 0) {
103 		device_printf(dev, "No AESNI support.\n");
104 		return (EINVAL);
105 	}
106 
107 	if ((cpu_feature2 & CPUID2_SSE41) == 0) {
108 		device_printf(dev, "No SSE4.1 support.\n");
109 		return (EINVAL);
110 	}
111 
112 	device_set_desc_copy(dev, "AES-CBC,AES-XTS,AES-GCM,AES-ICM");
113 	return (0);
114 }
115 
116 static void
117 aensi_cleanctx(void)
118 {
119 	int i;
120 
121 	/* XXX - no way to return driverid */
122 	CPU_FOREACH(i) {
123 		if (ctx_fpu[i] != NULL) {
124 			mtx_destroy(&ctx_mtx[i]);
125 			fpu_kern_free_ctx(ctx_fpu[i]);
126 		}
127 		ctx_fpu[i] = NULL;
128 	}
129 	free(ctx_mtx, M_AESNI);
130 	ctx_mtx = NULL;
131 	free(ctx_fpu, M_AESNI);
132 	ctx_fpu = NULL;
133 }
134 
135 static int
136 aesni_attach(device_t dev)
137 {
138 	struct aesni_softc *sc;
139 	int i;
140 
141 	sc = device_get_softc(dev);
142 	sc->dieing = 0;
143 	TAILQ_INIT(&sc->sessions);
144 	sc->sid = 1;
145 
146 	sc->cid = crypto_get_driverid(dev, CRYPTOCAP_F_HARDWARE |
147 	    CRYPTOCAP_F_SYNC);
148 	if (sc->cid < 0) {
149 		device_printf(dev, "Could not get crypto driver id.\n");
150 		return (ENOMEM);
151 	}
152 
153 	ctx_mtx = malloc(sizeof *ctx_mtx * (mp_maxid + 1), M_AESNI,
154 	    M_WAITOK|M_ZERO);
155 	ctx_fpu = malloc(sizeof *ctx_fpu * (mp_maxid + 1), M_AESNI,
156 	    M_WAITOK|M_ZERO);
157 
158 	CPU_FOREACH(i) {
159 		ctx_fpu[i] = fpu_kern_alloc_ctx(0);
160 		mtx_init(&ctx_mtx[i], "anifpumtx", NULL, MTX_DEF|MTX_NEW);
161 	}
162 
163 	rw_init(&sc->lock, "aesni_lock");
164 	crypto_register(sc->cid, CRYPTO_AES_CBC, 0, 0);
165 	crypto_register(sc->cid, CRYPTO_AES_ICM, 0, 0);
166 	crypto_register(sc->cid, CRYPTO_AES_NIST_GCM_16, 0, 0);
167 	crypto_register(sc->cid, CRYPTO_AES_128_NIST_GMAC, 0, 0);
168 	crypto_register(sc->cid, CRYPTO_AES_192_NIST_GMAC, 0, 0);
169 	crypto_register(sc->cid, CRYPTO_AES_256_NIST_GMAC, 0, 0);
170 	crypto_register(sc->cid, CRYPTO_AES_XTS, 0, 0);
171 	return (0);
172 }
173 
174 static int
175 aesni_detach(device_t dev)
176 {
177 	struct aesni_softc *sc;
178 	struct aesni_session *ses;
179 
180 	sc = device_get_softc(dev);
181 
182 	rw_wlock(&sc->lock);
183 	TAILQ_FOREACH(ses, &sc->sessions, next) {
184 		if (ses->used) {
185 			rw_wunlock(&sc->lock);
186 			device_printf(dev,
187 			    "Cannot detach, sessions still active.\n");
188 			return (EBUSY);
189 		}
190 	}
191 	sc->dieing = 1;
192 	while ((ses = TAILQ_FIRST(&sc->sessions)) != NULL) {
193 		TAILQ_REMOVE(&sc->sessions, ses, next);
194 		free(ses, M_AESNI);
195 	}
196 	rw_wunlock(&sc->lock);
197 	crypto_unregister_all(sc->cid);
198 
199 	rw_destroy(&sc->lock);
200 
201 	aensi_cleanctx();
202 
203 	return (0);
204 }
205 
206 static int
207 aesni_newsession(device_t dev, uint32_t *sidp, struct cryptoini *cri)
208 {
209 	struct aesni_softc *sc;
210 	struct aesni_session *ses;
211 	struct cryptoini *encini;
212 	int error;
213 
214 	if (sidp == NULL || cri == NULL) {
215 		CRYPTDEB("no sidp or cri");
216 		return (EINVAL);
217 	}
218 
219 	sc = device_get_softc(dev);
220 	if (sc->dieing)
221 		return (EINVAL);
222 
223 	ses = NULL;
224 	encini = NULL;
225 	for (; cri != NULL; cri = cri->cri_next) {
226 		switch (cri->cri_alg) {
227 		case CRYPTO_AES_CBC:
228 		case CRYPTO_AES_ICM:
229 		case CRYPTO_AES_XTS:
230 		case CRYPTO_AES_NIST_GCM_16:
231 			if (encini != NULL) {
232 				CRYPTDEB("encini already set");
233 				return (EINVAL);
234 			}
235 			encini = cri;
236 			break;
237 		case CRYPTO_AES_128_NIST_GMAC:
238 		case CRYPTO_AES_192_NIST_GMAC:
239 		case CRYPTO_AES_256_NIST_GMAC:
240 			/*
241 			 * nothing to do here, maybe in the future cache some
242 			 * values for GHASH
243 			 */
244 			break;
245 		default:
246 			CRYPTDEB("unhandled algorithm");
247 			return (EINVAL);
248 		}
249 	}
250 	if (encini == NULL) {
251 		CRYPTDEB("no cipher");
252 		return (EINVAL);
253 	}
254 
255 	rw_wlock(&sc->lock);
256 	if (sc->dieing) {
257 		rw_wunlock(&sc->lock);
258 		return (EINVAL);
259 	}
260 	/*
261 	 * Free sessions goes first, so if first session is used, we need to
262 	 * allocate one.
263 	 */
264 	ses = TAILQ_FIRST(&sc->sessions);
265 	if (ses == NULL || ses->used) {
266 		ses = malloc(sizeof(*ses), M_AESNI, M_NOWAIT | M_ZERO);
267 		if (ses == NULL) {
268 			rw_wunlock(&sc->lock);
269 			return (ENOMEM);
270 		}
271 		ses->id = sc->sid++;
272 	} else {
273 		TAILQ_REMOVE(&sc->sessions, ses, next);
274 	}
275 	ses->used = 1;
276 	TAILQ_INSERT_TAIL(&sc->sessions, ses, next);
277 	rw_wunlock(&sc->lock);
278 	ses->algo = encini->cri_alg;
279 
280 	error = aesni_cipher_setup(ses, encini);
281 	if (error != 0) {
282 		CRYPTDEB("setup failed");
283 		rw_wlock(&sc->lock);
284 		aesni_freesession_locked(sc, ses);
285 		rw_wunlock(&sc->lock);
286 		return (error);
287 	}
288 
289 	*sidp = ses->id;
290 	return (0);
291 }
292 
293 static void
294 aesni_freesession_locked(struct aesni_softc *sc, struct aesni_session *ses)
295 {
296 	uint32_t sid;
297 
298 	rw_assert(&sc->lock, RA_WLOCKED);
299 
300 	sid = ses->id;
301 	TAILQ_REMOVE(&sc->sessions, ses, next);
302 	*ses = (struct aesni_session){};
303 	ses->id = sid;
304 	TAILQ_INSERT_HEAD(&sc->sessions, ses, next);
305 }
306 
307 static int
308 aesni_freesession(device_t dev, uint64_t tid)
309 {
310 	struct aesni_softc *sc;
311 	struct aesni_session *ses;
312 	uint32_t sid;
313 
314 	sc = device_get_softc(dev);
315 	sid = ((uint32_t)tid) & 0xffffffff;
316 	rw_wlock(&sc->lock);
317 	TAILQ_FOREACH_REVERSE(ses, &sc->sessions, aesni_sessions_head, next) {
318 		if (ses->id == sid)
319 			break;
320 	}
321 	if (ses == NULL) {
322 		rw_wunlock(&sc->lock);
323 		return (EINVAL);
324 	}
325 	aesni_freesession_locked(sc, ses);
326 	rw_wunlock(&sc->lock);
327 	return (0);
328 }
329 
330 static int
331 aesni_process(device_t dev, struct cryptop *crp, int hint __unused)
332 {
333 	struct aesni_softc *sc = device_get_softc(dev);
334 	struct aesni_session *ses = NULL;
335 	struct cryptodesc *crd, *enccrd, *authcrd;
336 	int error, needauth;
337 
338 	error = 0;
339 	enccrd = NULL;
340 	authcrd = NULL;
341 	needauth = 0;
342 
343 	/* Sanity check. */
344 	if (crp == NULL)
345 		return (EINVAL);
346 
347 	if (crp->crp_callback == NULL || crp->crp_desc == NULL) {
348 		error = EINVAL;
349 		goto out;
350 	}
351 
352 	for (crd = crp->crp_desc; crd != NULL; crd = crd->crd_next) {
353 		switch (crd->crd_alg) {
354 		case CRYPTO_AES_CBC:
355 		case CRYPTO_AES_ICM:
356 		case CRYPTO_AES_XTS:
357 			if (enccrd != NULL) {
358 				error = EINVAL;
359 				goto out;
360 			}
361 			enccrd = crd;
362 			break;
363 
364 		case CRYPTO_AES_NIST_GCM_16:
365 			if (enccrd != NULL) {
366 				error = EINVAL;
367 				goto out;
368 			}
369 			enccrd = crd;
370 			needauth = 1;
371 			break;
372 
373 		case CRYPTO_AES_128_NIST_GMAC:
374 		case CRYPTO_AES_192_NIST_GMAC:
375 		case CRYPTO_AES_256_NIST_GMAC:
376 			if (authcrd != NULL) {
377 				error = EINVAL;
378 				goto out;
379 			}
380 			authcrd = crd;
381 			needauth = 1;
382 			break;
383 
384 		default:
385 			error = EINVAL;
386 			goto out;
387 		}
388 	}
389 
390 	if (enccrd == NULL || (needauth && authcrd == NULL)) {
391 		error = EINVAL;
392 		goto out;
393 	}
394 
395 	/* CBC & XTS can only handle full blocks for now */
396 	if ((enccrd->crd_alg == CRYPTO_AES_CBC || enccrd->crd_alg ==
397 	    CRYPTO_AES_XTS) && (enccrd->crd_len % AES_BLOCK_LEN) != 0) {
398 		error = EINVAL;
399 		goto out;
400 	}
401 
402 	rw_rlock(&sc->lock);
403 	TAILQ_FOREACH_REVERSE(ses, &sc->sessions, aesni_sessions_head, next) {
404 		if (ses->id == (crp->crp_sid & 0xffffffff))
405 			break;
406 	}
407 	rw_runlock(&sc->lock);
408 	if (ses == NULL) {
409 		error = EINVAL;
410 		goto out;
411 	}
412 
413 	error = aesni_cipher_process(ses, enccrd, authcrd, crp);
414 	if (error != 0)
415 		goto out;
416 
417 out:
418 	crp->crp_etype = error;
419 	crypto_done(crp);
420 	return (error);
421 }
422 
423 uint8_t *
424 aesni_cipher_alloc(struct cryptodesc *enccrd, struct cryptop *crp,
425     int *allocated)
426 {
427 	struct mbuf *m;
428 	struct uio *uio;
429 	struct iovec *iov;
430 	uint8_t *addr;
431 
432 	if (crp->crp_flags & CRYPTO_F_IMBUF) {
433 		m = (struct mbuf *)crp->crp_buf;
434 		if (m->m_next != NULL)
435 			goto alloc;
436 		addr = mtod(m, uint8_t *);
437 	} else if (crp->crp_flags & CRYPTO_F_IOV) {
438 		uio = (struct uio *)crp->crp_buf;
439 		if (uio->uio_iovcnt != 1)
440 			goto alloc;
441 		iov = uio->uio_iov;
442 		addr = (uint8_t *)iov->iov_base;
443 	} else
444 		addr = (uint8_t *)crp->crp_buf;
445 	*allocated = 0;
446 	addr += enccrd->crd_skip;
447 	return (addr);
448 
449 alloc:
450 	addr = malloc(enccrd->crd_len, M_AESNI, M_NOWAIT);
451 	if (addr != NULL) {
452 		*allocated = 1;
453 		crypto_copydata(crp->crp_flags, crp->crp_buf, enccrd->crd_skip,
454 		    enccrd->crd_len, addr);
455 	} else
456 		*allocated = 0;
457 	return (addr);
458 }
459 
460 static device_method_t aesni_methods[] = {
461 	DEVMETHOD(device_identify, aesni_identify),
462 	DEVMETHOD(device_probe, aesni_probe),
463 	DEVMETHOD(device_attach, aesni_attach),
464 	DEVMETHOD(device_detach, aesni_detach),
465 
466 	DEVMETHOD(cryptodev_newsession, aesni_newsession),
467 	DEVMETHOD(cryptodev_freesession, aesni_freesession),
468 	DEVMETHOD(cryptodev_process, aesni_process),
469 
470 	{0, 0},
471 };
472 
473 static driver_t aesni_driver = {
474 	"aesni",
475 	aesni_methods,
476 	sizeof(struct aesni_softc),
477 };
478 static devclass_t aesni_devclass;
479 
480 DRIVER_MODULE(aesni, nexus, aesni_driver, aesni_devclass, 0, 0);
481 MODULE_VERSION(aesni, 1);
482 MODULE_DEPEND(aesni, crypto, 1, 1, 1);
483 
484 static int
485 aesni_cipher_setup(struct aesni_session *ses, struct cryptoini *encini)
486 {
487 	struct fpu_kern_ctx *ctx;
488 	int error;
489 	int kt, ctxidx;
490 
491 	kt = is_fpu_kern_thread(0);
492 	if (!kt) {
493 		AQUIRE_CTX(ctxidx, ctx);
494 		error = fpu_kern_enter(curthread, ctx,
495 		    FPU_KERN_NORMAL | FPU_KERN_KTHR);
496 		if (error != 0)
497 			goto out;
498 	}
499 
500 	error = aesni_cipher_setup_common(ses, encini->cri_key,
501 	    encini->cri_klen);
502 
503 	if (!kt) {
504 		fpu_kern_leave(curthread, ctx);
505 out:
506 		RELEASE_CTX(ctxidx, ctx);
507 	}
508 	return (error);
509 }
510 
511 /*
512  * authcrd contains the associated date.
513  */
514 static int
515 aesni_cipher_process(struct aesni_session *ses, struct cryptodesc *enccrd,
516     struct cryptodesc *authcrd, struct cryptop *crp)
517 {
518 	struct fpu_kern_ctx *ctx;
519 	uint8_t iv[AES_BLOCK_LEN];
520 	uint8_t tag[GMAC_DIGEST_LEN];
521 	uint8_t *buf, *authbuf;
522 	int error, allocated, authallocated;
523 	int ivlen, encflag;
524 	int kt, ctxidx;
525 
526 	encflag = (enccrd->crd_flags & CRD_F_ENCRYPT) == CRD_F_ENCRYPT;
527 
528 	if ((enccrd->crd_alg == CRYPTO_AES_ICM ||
529 	    enccrd->crd_alg == CRYPTO_AES_NIST_GCM_16) &&
530 	    (enccrd->crd_flags & CRD_F_IV_EXPLICIT) == 0)
531 		return (EINVAL);
532 
533 	buf = aesni_cipher_alloc(enccrd, crp, &allocated);
534 	if (buf == NULL)
535 		return (ENOMEM);
536 
537 	error = 0;
538 	authbuf = NULL;
539 	authallocated = 0;
540 	if (authcrd != NULL) {
541 		authbuf = aesni_cipher_alloc(authcrd, crp, &authallocated);
542 		if (authbuf == NULL) {
543 			error = ENOMEM;
544 			goto out1;
545 		}
546 	}
547 
548 	kt = is_fpu_kern_thread(0);
549 	if (!kt) {
550 		AQUIRE_CTX(ctxidx, ctx);
551 		error = fpu_kern_enter(curthread, ctx,
552 		    FPU_KERN_NORMAL|FPU_KERN_KTHR);
553 		if (error != 0)
554 			goto out2;
555 	}
556 
557 	if ((enccrd->crd_flags & CRD_F_KEY_EXPLICIT) != 0) {
558 		error = aesni_cipher_setup_common(ses, enccrd->crd_key,
559 		    enccrd->crd_klen);
560 		if (error != 0)
561 			goto out;
562 	}
563 
564 	/* XXX - validate that enccrd and authcrd have/use same key? */
565 	switch (enccrd->crd_alg) {
566 	case CRYPTO_AES_CBC:
567 	case CRYPTO_AES_ICM:
568 		ivlen = AES_BLOCK_LEN;
569 		break;
570 	case CRYPTO_AES_XTS:
571 		ivlen = 8;
572 		break;
573 	case CRYPTO_AES_NIST_GCM_16:
574 		ivlen = 12;	/* should support arbitarily larger */
575 		break;
576 	}
577 
578 	/* Setup iv */
579 	if (encflag) {
580 		if ((enccrd->crd_flags & CRD_F_IV_EXPLICIT) != 0)
581 			bcopy(enccrd->crd_iv, iv, ivlen);
582 		else
583 			arc4rand(iv, ivlen, 0);
584 
585 		if ((enccrd->crd_flags & CRD_F_IV_PRESENT) == 0)
586 			crypto_copyback(crp->crp_flags, crp->crp_buf,
587 			    enccrd->crd_inject, ivlen, iv);
588 	} else {
589 		if ((enccrd->crd_flags & CRD_F_IV_EXPLICIT) != 0)
590 			bcopy(enccrd->crd_iv, iv, ivlen);
591 		else
592 			crypto_copydata(crp->crp_flags, crp->crp_buf,
593 			    enccrd->crd_inject, ivlen, iv);
594 	}
595 
596 	if (authcrd != NULL && !encflag)
597 		crypto_copydata(crp->crp_flags, crp->crp_buf,
598 		    authcrd->crd_inject, GMAC_DIGEST_LEN, tag);
599 	else
600 		bzero(tag, sizeof tag);
601 
602 	/* Do work */
603 	switch (ses->algo) {
604 	case CRYPTO_AES_CBC:
605 		if (encflag)
606 			aesni_encrypt_cbc(ses->rounds, ses->enc_schedule,
607 			    enccrd->crd_len, buf, buf, iv);
608 		else
609 			aesni_decrypt_cbc(ses->rounds, ses->dec_schedule,
610 			    enccrd->crd_len, buf, iv);
611 		break;
612 	case CRYPTO_AES_ICM:
613 		/* encryption & decryption are the same */
614 		aesni_encrypt_icm(ses->rounds, ses->enc_schedule,
615 		    enccrd->crd_len, buf, buf, iv);
616 		break;
617 	case CRYPTO_AES_XTS:
618 		if (encflag)
619 			aesni_encrypt_xts(ses->rounds, ses->enc_schedule,
620 			    ses->xts_schedule, enccrd->crd_len, buf, buf,
621 			    iv);
622 		else
623 			aesni_decrypt_xts(ses->rounds, ses->dec_schedule,
624 			    ses->xts_schedule, enccrd->crd_len, buf, buf,
625 			    iv);
626 		break;
627 	case CRYPTO_AES_NIST_GCM_16:
628 		if (encflag)
629 			AES_GCM_encrypt(buf, buf, authbuf, iv, tag,
630 			    enccrd->crd_len, authcrd->crd_len, ivlen,
631 			    ses->enc_schedule, ses->rounds);
632 		else {
633 			if (!AES_GCM_decrypt(buf, buf, authbuf, iv, tag,
634 			    enccrd->crd_len, authcrd->crd_len, ivlen,
635 			    ses->enc_schedule, ses->rounds))
636 				error = EBADMSG;
637 		}
638 		break;
639 	}
640 
641 	if (allocated)
642 		crypto_copyback(crp->crp_flags, crp->crp_buf, enccrd->crd_skip,
643 		    enccrd->crd_len, buf);
644 
645 	if (!error && authcrd != NULL) {
646 		crypto_copyback(crp->crp_flags, crp->crp_buf,
647 		    authcrd->crd_inject, GMAC_DIGEST_LEN, tag);
648 	}
649 
650 out:
651 	if (!kt) {
652 		fpu_kern_leave(curthread, ctx);
653 out2:
654 		RELEASE_CTX(ctxidx, ctx);
655 	}
656 
657 out1:
658 	if (allocated) {
659 		bzero(buf, enccrd->crd_len);
660 		free(buf, M_AESNI);
661 	}
662 	if (authallocated)
663 		free(authbuf, M_AESNI);
664 	return (error);
665 }
666