xref: /netbsd-src/sys/opencrypto/crypto.c (revision 6a493d6bc668897c91594964a732d38505b70cbb)
1 /*	$NetBSD: crypto.c,v 1.41 2011/06/09 14:41:24 drochner Exp $ */
2 /*	$FreeBSD: src/sys/opencrypto/crypto.c,v 1.4.2.5 2003/02/26 00:14:05 sam Exp $	*/
3 /*	$OpenBSD: crypto.c,v 1.41 2002/07/17 23:52:38 art Exp $	*/
4 
5 /*-
6  * Copyright (c) 2008 The NetBSD Foundation, Inc.
7  * All rights reserved.
8  *
9  * This code is derived from software contributed to The NetBSD Foundation
10  * by Coyote Point Systems, Inc.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
23  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
24  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
25  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31  * POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 /*
35  * The author of this code is Angelos D. Keromytis (angelos@cis.upenn.edu)
36  *
37  * This code was written by Angelos D. Keromytis in Athens, Greece, in
38  * February 2000. Network Security Technologies Inc. (NSTI) kindly
39  * supported the development of this code.
40  *
41  * Copyright (c) 2000, 2001 Angelos D. Keromytis
42  *
43  * Permission to use, copy, and modify this software with or without fee
44  * is hereby granted, provided that this entire notice is included in
45  * all source code copies of any software which is or includes a copy or
46  * modification of this software.
47  *
48  * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
49  * IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
50  * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
51  * MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
52  * PURPOSE.
53  */
54 
55 #include <sys/cdefs.h>
56 __KERNEL_RCSID(0, "$NetBSD: crypto.c,v 1.41 2011/06/09 14:41:24 drochner Exp $");
57 
58 #include <sys/param.h>
59 #include <sys/reboot.h>
60 #include <sys/systm.h>
61 #include <sys/malloc.h>
62 #include <sys/proc.h>
63 #include <sys/pool.h>
64 #include <sys/kthread.h>
65 #include <sys/once.h>
66 #include <sys/sysctl.h>
67 #include <sys/intr.h>
68 
69 #include "opt_ocf.h"
70 #include <opencrypto/cryptodev.h>
71 #include <opencrypto/xform.h>			/* XXX for M_XDATA */
72 
73 kmutex_t crypto_q_mtx;
74 kmutex_t crypto_ret_q_mtx;
75 kcondvar_t cryptoret_cv;
76 kmutex_t crypto_mtx;
77 
78 /* below are kludges for residual code wrtitten to FreeBSD interfaces */
79   #define SWI_CRYPTO 17
80   #define register_swi(lvl, fn)  \
81   softint_establish(SOFTINT_NET|SOFTINT_MPSAFE, (void (*)(void *))fn, NULL)
82   #define unregister_swi(lvl, fn)  softint_disestablish(softintr_cookie)
83   #define setsoftcrypto(x) softint_schedule(x)
84 
85 int crypto_ret_q_check(struct cryptop *);
86 
87 /*
88  * Crypto drivers register themselves by allocating a slot in the
89  * crypto_drivers table with crypto_get_driverid() and then registering
90  * each algorithm they support with crypto_register() and crypto_kregister().
91  */
92 static	struct cryptocap *crypto_drivers;
93 static	int crypto_drivers_num;
94 static	void *softintr_cookie;
95 
96 /*
97  * There are two queues for crypto requests; one for symmetric (e.g.
98  * cipher) operations and one for asymmetric (e.g. MOD) operations.
99  * See below for how synchronization is handled.
100  */
101 static	TAILQ_HEAD(,cryptop) crp_q =		/* request queues */
102 		TAILQ_HEAD_INITIALIZER(crp_q);
103 static	TAILQ_HEAD(,cryptkop) crp_kq =
104 		TAILQ_HEAD_INITIALIZER(crp_kq);
105 
106 /*
107  * There are two queues for processing completed crypto requests; one
108  * for the symmetric and one for the asymmetric ops.  We only need one
109  * but have two to avoid type futzing (cryptop vs. cryptkop).  See below
110  * for how synchronization is handled.
111  */
112 static	TAILQ_HEAD(crprethead, cryptop) crp_ret_q =	/* callback queues */
113 		TAILQ_HEAD_INITIALIZER(crp_ret_q);
114 static	TAILQ_HEAD(krprethead, cryptkop) crp_ret_kq =
115 		TAILQ_HEAD_INITIALIZER(crp_ret_kq);
116 
117 /*
118  * XXX these functions are ghastly hacks for when the submission
119  * XXX routines discover a request that was not CBIMM is already
120  * XXX done, and must be yanked from the retq (where _done) put it
121  * XXX as cryptoret won't get the chance.  The queue is walked backwards
122  * XXX as the request is generally the last one queued.
123  *
124  *	 call with the lock held, or else.
125  */
126 int
127 crypto_ret_q_remove(struct cryptop *crp)
128 {
129 	struct cryptop * acrp, *next;
130 
131 	TAILQ_FOREACH_REVERSE_SAFE(acrp, &crp_ret_q, crprethead, crp_next, next) {
132 		if (acrp == crp) {
133 			TAILQ_REMOVE(&crp_ret_q, crp, crp_next);
134 			crp->crp_flags &= (~CRYPTO_F_ONRETQ);
135 			return 1;
136 		}
137 	}
138 	return 0;
139 }
140 
141 int
142 crypto_ret_kq_remove(struct cryptkop *krp)
143 {
144 	struct cryptkop * akrp, *next;
145 
146 	TAILQ_FOREACH_REVERSE_SAFE(akrp, &crp_ret_kq, krprethead, krp_next, next) {
147 		if (akrp == krp) {
148 			TAILQ_REMOVE(&crp_ret_kq, krp, krp_next);
149 			krp->krp_flags &= (~CRYPTO_F_ONRETQ);
150 			return 1;
151 		}
152 	}
153 	return 0;
154 }
155 
156 /*
157  * Crypto op and desciptor data structures are allocated
158  * from separate private zones(FreeBSD)/pools(netBSD/OpenBSD) .
159  */
160 struct pool cryptop_pool;
161 struct pool cryptodesc_pool;
162 struct pool cryptkop_pool;
163 
164 int	crypto_usercrypto = 1;		/* userland may open /dev/crypto */
165 int	crypto_userasymcrypto = 1;	/* userland may do asym crypto reqs */
166 /*
167  * cryptodevallowsoft is (intended to be) sysctl'able, controlling
168  * access to hardware versus software transforms as below:
169  *
170  * crypto_devallowsoft < 0:  Force userlevel requests to use software
171  *                              transforms, always
172  * crypto_devallowsoft = 0:  Use hardware if present, grant userlevel
173  *                              requests for non-accelerated transforms
174  *                              (handling the latter in software)
175  * crypto_devallowsoft > 0:  Allow user requests only for transforms which
176  *                               are hardware-accelerated.
177  */
178 int	crypto_devallowsoft = 1;	/* only use hardware crypto */
179 
180 SYSCTL_SETUP(sysctl_opencrypto_setup, "sysctl opencrypto subtree setup")
181 {
182 	sysctl_createv(clog, 0, NULL, NULL,
183 		       CTLFLAG_PERMANENT,
184 		       CTLTYPE_NODE, "kern", NULL,
185 		       NULL, 0, NULL, 0,
186 		       CTL_KERN, CTL_EOL);
187 	sysctl_createv(clog, 0, NULL, NULL,
188 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
189 		       CTLTYPE_INT, "usercrypto",
190 		       SYSCTL_DESCR("Enable/disable user-mode access to "
191 			   "crypto support"),
192 		       NULL, 0, &crypto_usercrypto, 0,
193 		       CTL_KERN, CTL_CREATE, CTL_EOL);
194 	sysctl_createv(clog, 0, NULL, NULL,
195 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
196 		       CTLTYPE_INT, "userasymcrypto",
197 		       SYSCTL_DESCR("Enable/disable user-mode access to "
198 			   "asymmetric crypto support"),
199 		       NULL, 0, &crypto_userasymcrypto, 0,
200 		       CTL_KERN, CTL_CREATE, CTL_EOL);
201 	sysctl_createv(clog, 0, NULL, NULL,
202 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
203 		       CTLTYPE_INT, "cryptodevallowsoft",
204 		       SYSCTL_DESCR("Enable/disable use of software "
205 			   "asymmetric crypto support"),
206 		       NULL, 0, &crypto_devallowsoft, 0,
207 		       CTL_KERN, CTL_CREATE, CTL_EOL);
208 }
209 
210 MALLOC_DEFINE(M_CRYPTO_DATA, "crypto", "crypto session records");
211 
212 /*
213  * Synchronization: read carefully, this is non-trivial.
214  *
215  * Crypto requests are submitted via crypto_dispatch.  Typically
216  * these come in from network protocols at spl0 (output path) or
217  * spl[,soft]net (input path).
218  *
219  * Requests are typically passed on the driver directly, but they
220  * may also be queued for processing by a software interrupt thread,
221  * cryptointr, that runs at splsoftcrypto.  This thread dispatches
222  * the requests to crypto drivers (h/w or s/w) who call crypto_done
223  * when a request is complete.  Hardware crypto drivers are assumed
224  * to register their IRQ's as network devices so their interrupt handlers
225  * and subsequent "done callbacks" happen at spl[imp,net].
226  *
227  * Completed crypto ops are queued for a separate kernel thread that
228  * handles the callbacks at spl0.  This decoupling insures the crypto
229  * driver interrupt service routine is not delayed while the callback
230  * takes place and that callbacks are delivered after a context switch
231  * (as opposed to a software interrupt that clients must block).
232  *
233  * This scheme is not intended for SMP machines.
234  */
235 static	void cryptointr(void);		/* swi thread to dispatch ops */
236 static	void cryptoret(void);		/* kernel thread for callbacks*/
237 static	struct lwp *cryptothread;
238 static	void crypto_destroy(void);
239 static	int crypto_invoke(struct cryptop *crp, int hint);
240 static	int crypto_kinvoke(struct cryptkop *krp, int hint);
241 
242 static struct cryptostats cryptostats;
243 #ifdef CRYPTO_TIMING
244 static	int crypto_timing = 0;
245 #endif
246 
247 static int
248 crypto_init0(void)
249 {
250 	int error;
251 
252 	mutex_init(&crypto_mtx, MUTEX_DEFAULT, IPL_NONE);
253 	mutex_init(&crypto_q_mtx, MUTEX_DEFAULT, IPL_NET);
254 	mutex_init(&crypto_ret_q_mtx, MUTEX_DEFAULT, IPL_NET);
255 	cv_init(&cryptoret_cv, "crypto_w");
256 	pool_init(&cryptop_pool, sizeof(struct cryptop), 0, 0,
257 		  0, "cryptop", NULL, IPL_NET);
258 	pool_init(&cryptodesc_pool, sizeof(struct cryptodesc), 0, 0,
259 		  0, "cryptodesc", NULL, IPL_NET);
260 	pool_init(&cryptkop_pool, sizeof(struct cryptkop), 0, 0,
261 		  0, "cryptkop", NULL, IPL_NET);
262 
263 	crypto_drivers = malloc(CRYPTO_DRIVERS_INITIAL *
264 	    sizeof(struct cryptocap), M_CRYPTO_DATA, M_NOWAIT | M_ZERO);
265 	if (crypto_drivers == NULL) {
266 		printf("crypto_init: cannot malloc driver table\n");
267 		return 0;
268 	}
269 	crypto_drivers_num = CRYPTO_DRIVERS_INITIAL;
270 
271 	softintr_cookie = register_swi(SWI_CRYPTO, cryptointr);
272 	error = kthread_create(PRI_NONE, KTHREAD_MPSAFE, NULL,
273 	    (void (*)(void *))cryptoret, NULL, &cryptothread, "cryptoret");
274 	if (error) {
275 		printf("crypto_init: cannot start cryptoret thread; error %d",
276 			error);
277 		crypto_destroy();
278 	}
279 
280 	return 0;
281 }
282 
283 void
284 crypto_init(void)
285 {
286 	static ONCE_DECL(crypto_init_once);
287 
288 	RUN_ONCE(&crypto_init_once, crypto_init0);
289 }
290 
291 static void
292 crypto_destroy(void)
293 {
294 	/* XXX no wait to reclaim zones */
295 	if (crypto_drivers != NULL)
296 		free(crypto_drivers, M_CRYPTO_DATA);
297 	unregister_swi(SWI_CRYPTO, cryptointr);
298 }
299 
300 /*
301  * Create a new session.  Must be called with crypto_mtx held.
302  */
303 int
304 crypto_newsession(u_int64_t *sid, struct cryptoini *cri, int hard)
305 {
306 	struct cryptoini *cr;
307 	u_int32_t hid, lid;
308 	int err = EINVAL;
309 
310 	mutex_enter(&crypto_mtx);
311 
312 	if (crypto_drivers == NULL)
313 		goto done;
314 
315 	/*
316 	 * The algorithm we use here is pretty stupid; just use the
317 	 * first driver that supports all the algorithms we need.
318 	 *
319 	 * XXX We need more smarts here (in real life too, but that's
320 	 * XXX another story altogether).
321 	 */
322 
323 	for (hid = 0; hid < crypto_drivers_num; hid++) {
324 		/*
325 		 * If it's not initialized or has remaining sessions
326 		 * referencing it, skip.
327 		 */
328 		if (crypto_drivers[hid].cc_newsession == NULL ||
329 		    (crypto_drivers[hid].cc_flags & CRYPTOCAP_F_CLEANUP))
330 			continue;
331 
332 		/* Hardware required -- ignore software drivers. */
333 		if (hard > 0 &&
334 		    (crypto_drivers[hid].cc_flags & CRYPTOCAP_F_SOFTWARE))
335 			continue;
336 		/* Software required -- ignore hardware drivers. */
337 		if (hard < 0 &&
338 		    (crypto_drivers[hid].cc_flags & CRYPTOCAP_F_SOFTWARE) == 0)
339 			continue;
340 
341 		/* See if all the algorithms are supported. */
342 		for (cr = cri; cr; cr = cr->cri_next)
343 			if (crypto_drivers[hid].cc_alg[cr->cri_alg] == 0) {
344 				DPRINTF(("crypto_newsession: alg %d not supported\n", cr->cri_alg));
345 				break;
346 			}
347 
348 		if (cr == NULL) {
349 			/* Ok, all algorithms are supported. */
350 
351 			/*
352 			 * Can't do everything in one session.
353 			 *
354 			 * XXX Fix this. We need to inject a "virtual" session layer right
355 			 * XXX about here.
356 			 */
357 
358 			/* Call the driver initialization routine. */
359 			lid = hid;		/* Pass the driver ID. */
360 			err = crypto_drivers[hid].cc_newsession(
361 					crypto_drivers[hid].cc_arg, &lid, cri);
362 			if (err == 0) {
363 				(*sid) = hid;
364 				(*sid) <<= 32;
365 				(*sid) |= (lid & 0xffffffff);
366 				crypto_drivers[hid].cc_sessions++;
367 			}
368 			goto done;
369 			/*break;*/
370 		}
371 	}
372 done:
373 	mutex_exit(&crypto_mtx);
374 	return err;
375 }
376 
377 /*
378  * Delete an existing session (or a reserved session on an unregistered
379  * driver).  Must be called with crypto_mtx mutex held.
380  */
381 int
382 crypto_freesession(u_int64_t sid)
383 {
384 	u_int32_t hid;
385 	int err = 0;
386 
387 	mutex_enter(&crypto_mtx);
388 
389 	if (crypto_drivers == NULL) {
390 		err = EINVAL;
391 		goto done;
392 	}
393 
394 	/* Determine two IDs. */
395 	hid = CRYPTO_SESID2HID(sid);
396 
397 	if (hid >= crypto_drivers_num) {
398 		err = ENOENT;
399 		goto done;
400 	}
401 
402 	if (crypto_drivers[hid].cc_sessions)
403 		crypto_drivers[hid].cc_sessions--;
404 
405 	/* Call the driver cleanup routine, if available. */
406 	if (crypto_drivers[hid].cc_freesession) {
407 		err = crypto_drivers[hid].cc_freesession(
408 				crypto_drivers[hid].cc_arg, sid);
409 	}
410 	else
411 		err = 0;
412 
413 	/*
414 	 * If this was the last session of a driver marked as invalid,
415 	 * make the entry available for reuse.
416 	 */
417 	if ((crypto_drivers[hid].cc_flags & CRYPTOCAP_F_CLEANUP) &&
418 	    crypto_drivers[hid].cc_sessions == 0)
419 		memset(&crypto_drivers[hid], 0, sizeof(struct cryptocap));
420 
421 done:
422 	mutex_exit(&crypto_mtx);
423 	return err;
424 }
425 
426 /*
427  * Return an unused driver id.  Used by drivers prior to registering
428  * support for the algorithms they handle.
429  */
430 int32_t
431 crypto_get_driverid(u_int32_t flags)
432 {
433 	struct cryptocap *newdrv;
434 	int i;
435 
436 	crypto_init();		/* XXX oh, this is foul! */
437 
438 	mutex_enter(&crypto_mtx);
439 	for (i = 0; i < crypto_drivers_num; i++)
440 		if (crypto_drivers[i].cc_process == NULL &&
441 		    (crypto_drivers[i].cc_flags & CRYPTOCAP_F_CLEANUP) == 0 &&
442 		    crypto_drivers[i].cc_sessions == 0)
443 			break;
444 
445 	/* Out of entries, allocate some more. */
446 	if (i == crypto_drivers_num) {
447 		/* Be careful about wrap-around. */
448 		if (2 * crypto_drivers_num <= crypto_drivers_num) {
449 			mutex_exit(&crypto_mtx);
450 			printf("crypto: driver count wraparound!\n");
451 			return -1;
452 		}
453 
454 		newdrv = malloc(2 * crypto_drivers_num *
455 		    sizeof(struct cryptocap), M_CRYPTO_DATA, M_NOWAIT|M_ZERO);
456 		if (newdrv == NULL) {
457 			mutex_exit(&crypto_mtx);
458 			printf("crypto: no space to expand driver table!\n");
459 			return -1;
460 		}
461 
462 		memcpy(newdrv, crypto_drivers,
463 		    crypto_drivers_num * sizeof(struct cryptocap));
464 
465 		crypto_drivers_num *= 2;
466 
467 		free(crypto_drivers, M_CRYPTO_DATA);
468 		crypto_drivers = newdrv;
469 	}
470 
471 	/* NB: state is zero'd on free */
472 	crypto_drivers[i].cc_sessions = 1;	/* Mark */
473 	crypto_drivers[i].cc_flags = flags;
474 
475 	if (bootverbose)
476 		printf("crypto: assign driver %u, flags %u\n", i, flags);
477 
478 	mutex_exit(&crypto_mtx);
479 
480 	return i;
481 }
482 
483 static struct cryptocap *
484 crypto_checkdriver(u_int32_t hid)
485 {
486 	if (crypto_drivers == NULL)
487 		return NULL;
488 	return (hid >= crypto_drivers_num ? NULL : &crypto_drivers[hid]);
489 }
490 
491 /*
492  * Register support for a key-related algorithm.  This routine
493  * is called once for each algorithm supported a driver.
494  */
495 int
496 crypto_kregister(u_int32_t driverid, int kalg, u_int32_t flags,
497     int (*kprocess)(void *, struct cryptkop *, int),
498     void *karg)
499 {
500 	struct cryptocap *cap;
501 	int err;
502 
503 	mutex_enter(&crypto_mtx);
504 
505 	cap = crypto_checkdriver(driverid);
506 	if (cap != NULL &&
507 	    (CRK_ALGORITM_MIN <= kalg && kalg <= CRK_ALGORITHM_MAX)) {
508 		/*
509 		 * XXX Do some performance testing to determine placing.
510 		 * XXX We probably need an auxiliary data structure that
511 		 * XXX describes relative performances.
512 		 */
513 
514 		cap->cc_kalg[kalg] = flags | CRYPTO_ALG_FLAG_SUPPORTED;
515 		if (bootverbose) {
516 			printf("crypto: driver %u registers key alg %u "
517 			       " flags %u\n",
518 				driverid,
519 				kalg,
520 				flags
521 			);
522 		}
523 
524 		if (cap->cc_kprocess == NULL) {
525 			cap->cc_karg = karg;
526 			cap->cc_kprocess = kprocess;
527 		}
528 		err = 0;
529 	} else
530 		err = EINVAL;
531 
532 	mutex_exit(&crypto_mtx);
533 	return err;
534 }
535 
536 /*
537  * Register support for a non-key-related algorithm.  This routine
538  * is called once for each such algorithm supported by a driver.
539  */
540 int
541 crypto_register(u_int32_t driverid, int alg, u_int16_t maxoplen,
542     u_int32_t flags,
543     int (*newses)(void *, u_int32_t*, struct cryptoini*),
544     int (*freeses)(void *, u_int64_t),
545     int (*process)(void *, struct cryptop *, int),
546     void *arg)
547 {
548 	struct cryptocap *cap;
549 	int err;
550 
551 	mutex_enter(&crypto_mtx);
552 
553 	cap = crypto_checkdriver(driverid);
554 	/* NB: algorithms are in the range [1..max] */
555 	if (cap != NULL &&
556 	    (CRYPTO_ALGORITHM_MIN <= alg && alg <= CRYPTO_ALGORITHM_MAX)) {
557 		/*
558 		 * XXX Do some performance testing to determine placing.
559 		 * XXX We probably need an auxiliary data structure that
560 		 * XXX describes relative performances.
561 		 */
562 
563 		cap->cc_alg[alg] = flags | CRYPTO_ALG_FLAG_SUPPORTED;
564 		cap->cc_max_op_len[alg] = maxoplen;
565 		if (bootverbose) {
566 			printf("crypto: driver %u registers alg %u "
567 				"flags %u maxoplen %u\n",
568 				driverid,
569 				alg,
570 				flags,
571 				maxoplen
572 			);
573 		}
574 
575 		if (cap->cc_process == NULL) {
576 			cap->cc_arg = arg;
577 			cap->cc_newsession = newses;
578 			cap->cc_process = process;
579 			cap->cc_freesession = freeses;
580 			cap->cc_sessions = 0;		/* Unmark */
581 		}
582 		err = 0;
583 	} else
584 		err = EINVAL;
585 
586 	mutex_exit(&crypto_mtx);
587 	return err;
588 }
589 
590 /*
591  * Unregister a crypto driver. If there are pending sessions using it,
592  * leave enough information around so that subsequent calls using those
593  * sessions will correctly detect the driver has been unregistered and
594  * reroute requests.
595  */
596 int
597 crypto_unregister(u_int32_t driverid, int alg)
598 {
599 	int i, err;
600 	u_int32_t ses;
601 	struct cryptocap *cap;
602 
603 	mutex_enter(&crypto_mtx);
604 
605 	cap = crypto_checkdriver(driverid);
606 	if (cap != NULL &&
607 	    (CRYPTO_ALGORITHM_MIN <= alg && alg <= CRYPTO_ALGORITHM_MAX) &&
608 	    cap->cc_alg[alg] != 0) {
609 		cap->cc_alg[alg] = 0;
610 		cap->cc_max_op_len[alg] = 0;
611 
612 		/* Was this the last algorithm ? */
613 		for (i = 1; i <= CRYPTO_ALGORITHM_MAX; i++)
614 			if (cap->cc_alg[i] != 0)
615 				break;
616 
617 		if (i == CRYPTO_ALGORITHM_MAX + 1) {
618 			ses = cap->cc_sessions;
619 			memset(cap, 0, sizeof(struct cryptocap));
620 			if (ses != 0) {
621 				/*
622 				 * If there are pending sessions, just mark as invalid.
623 				 */
624 				cap->cc_flags |= CRYPTOCAP_F_CLEANUP;
625 				cap->cc_sessions = ses;
626 			}
627 		}
628 		err = 0;
629 	} else
630 		err = EINVAL;
631 
632 	mutex_exit(&crypto_mtx);
633 	return err;
634 }
635 
636 /*
637  * Unregister all algorithms associated with a crypto driver.
638  * If there are pending sessions using it, leave enough information
639  * around so that subsequent calls using those sessions will
640  * correctly detect the driver has been unregistered and reroute
641  * requests.
642  *
643  * XXX careful.  Don't change this to call crypto_unregister() for each
644  * XXX registered algorithm unless you drop the mutex across the calls;
645  * XXX you can't take it recursively.
646  */
647 int
648 crypto_unregister_all(u_int32_t driverid)
649 {
650 	int i, err;
651 	u_int32_t ses;
652 	struct cryptocap *cap;
653 
654 	mutex_enter(&crypto_mtx);
655 	cap = crypto_checkdriver(driverid);
656 	if (cap != NULL) {
657 		for (i = CRYPTO_ALGORITHM_MIN; i <= CRYPTO_ALGORITHM_MAX; i++) {
658 			cap->cc_alg[i] = 0;
659 			cap->cc_max_op_len[i] = 0;
660 		}
661 		ses = cap->cc_sessions;
662 		memset(cap, 0, sizeof(struct cryptocap));
663 		if (ses != 0) {
664 			/*
665 			 * If there are pending sessions, just mark as invalid.
666 			 */
667 			cap->cc_flags |= CRYPTOCAP_F_CLEANUP;
668 			cap->cc_sessions = ses;
669 		}
670 		err = 0;
671 	} else
672 		err = EINVAL;
673 
674 	mutex_exit(&crypto_mtx);
675 	return err;
676 }
677 
678 /*
679  * Clear blockage on a driver.  The what parameter indicates whether
680  * the driver is now ready for cryptop's and/or cryptokop's.
681  */
682 int
683 crypto_unblock(u_int32_t driverid, int what)
684 {
685 	struct cryptocap *cap;
686 	int needwakeup, err;
687 
688 	mutex_spin_enter(&crypto_q_mtx);
689 	cap = crypto_checkdriver(driverid);
690 	if (cap != NULL) {
691 		needwakeup = 0;
692 		if (what & CRYPTO_SYMQ) {
693 			needwakeup |= cap->cc_qblocked;
694 			cap->cc_qblocked = 0;
695 		}
696 		if (what & CRYPTO_ASYMQ) {
697 			needwakeup |= cap->cc_kqblocked;
698 			cap->cc_kqblocked = 0;
699 		}
700 		err = 0;
701 		if (needwakeup)
702 			setsoftcrypto(softintr_cookie);
703 		mutex_spin_exit(&crypto_q_mtx);
704 	} else {
705 		err = EINVAL;
706 		mutex_spin_exit(&crypto_q_mtx);
707 	}
708 
709 	return err;
710 }
711 
712 /*
713  * Dispatch a crypto request to a driver or queue
714  * it, to be processed by the kernel thread.
715  */
716 int
717 crypto_dispatch(struct cryptop *crp)
718 {
719 	u_int32_t hid = CRYPTO_SESID2HID(crp->crp_sid);
720 	int result;
721 
722 	mutex_spin_enter(&crypto_q_mtx);
723 	DPRINTF(("crypto_dispatch: crp %p, alg %d\n",
724 		crp, crp->crp_desc->crd_alg));
725 
726 	cryptostats.cs_ops++;
727 
728 #ifdef CRYPTO_TIMING
729 	if (crypto_timing)
730 		nanouptime(&crp->crp_tstamp);
731 #endif
732 	if ((crp->crp_flags & CRYPTO_F_BATCH) == 0) {
733 		struct cryptocap *cap;
734 		/*
735 		 * Caller marked the request to be processed
736 		 * immediately; dispatch it directly to the
737 		 * driver unless the driver is currently blocked.
738 		 */
739 		cap = crypto_checkdriver(hid);
740 		if (cap && !cap->cc_qblocked) {
741 			mutex_spin_exit(&crypto_q_mtx);
742 			result = crypto_invoke(crp, 0);
743 			if (result == ERESTART) {
744 				/*
745 				 * The driver ran out of resources, mark the
746 				 * driver ``blocked'' for cryptop's and put
747 				 * the op on the queue.
748 				 */
749 				mutex_spin_enter(&crypto_q_mtx);
750 				crypto_drivers[hid].cc_qblocked = 1;
751 				TAILQ_INSERT_HEAD(&crp_q, crp, crp_next);
752 				cryptostats.cs_blocks++;
753 				mutex_spin_exit(&crypto_q_mtx);
754 			}
755 			goto out_released;
756 		} else {
757 			/*
758 			 * The driver is blocked, just queue the op until
759 			 * it unblocks and the swi thread gets kicked.
760 			 */
761 			TAILQ_INSERT_TAIL(&crp_q, crp, crp_next);
762 			result = 0;
763 		}
764 	} else {
765 		int wasempty = TAILQ_EMPTY(&crp_q);
766 		/*
767 		 * Caller marked the request as ``ok to delay'';
768 		 * queue it for the swi thread.  This is desirable
769 		 * when the operation is low priority and/or suitable
770 		 * for batching.
771 		 */
772 		TAILQ_INSERT_TAIL(&crp_q, crp, crp_next);
773 		if (wasempty) {
774 			setsoftcrypto(softintr_cookie);
775 			mutex_spin_exit(&crypto_q_mtx);
776 			result = 0;
777 			goto out_released;
778 		}
779 
780 		result = 0;
781 	}
782 
783 	mutex_spin_exit(&crypto_q_mtx);
784 out_released:
785 	return result;
786 }
787 
788 /*
789  * Add an asymetric crypto request to a queue,
790  * to be processed by the kernel thread.
791  */
792 int
793 crypto_kdispatch(struct cryptkop *krp)
794 {
795 	struct cryptocap *cap;
796 	int result;
797 
798 	mutex_spin_enter(&crypto_q_mtx);
799 	cryptostats.cs_kops++;
800 
801 	cap = crypto_checkdriver(krp->krp_hid);
802 	if (cap && !cap->cc_kqblocked) {
803 		mutex_spin_exit(&crypto_q_mtx);
804 		result = crypto_kinvoke(krp, 0);
805 		if (result == ERESTART) {
806 			/*
807 			 * The driver ran out of resources, mark the
808 			 * driver ``blocked'' for cryptop's and put
809 			 * the op on the queue.
810 			 */
811 			mutex_spin_enter(&crypto_q_mtx);
812 			crypto_drivers[krp->krp_hid].cc_kqblocked = 1;
813 			TAILQ_INSERT_HEAD(&crp_kq, krp, krp_next);
814 			cryptostats.cs_kblocks++;
815 			mutex_spin_exit(&crypto_q_mtx);
816 		}
817 	} else {
818 		/*
819 		 * The driver is blocked, just queue the op until
820 		 * it unblocks and the swi thread gets kicked.
821 		 */
822 		TAILQ_INSERT_TAIL(&crp_kq, krp, krp_next);
823 		result = 0;
824 		mutex_spin_exit(&crypto_q_mtx);
825 	}
826 
827 	return result;
828 }
829 
830 /*
831  * Dispatch an assymetric crypto request to the appropriate crypto devices.
832  */
833 static int
834 crypto_kinvoke(struct cryptkop *krp, int hint)
835 {
836 	u_int32_t hid;
837 	int error;
838 
839 	/* Sanity checks. */
840 	if (krp == NULL)
841 		return EINVAL;
842 	if (krp->krp_callback == NULL) {
843 		cv_destroy(&krp->krp_cv);
844 		pool_put(&cryptkop_pool, krp);
845 		return EINVAL;
846 	}
847 
848 	mutex_enter(&crypto_mtx);
849 	for (hid = 0; hid < crypto_drivers_num; hid++) {
850 		if ((crypto_drivers[hid].cc_flags & CRYPTOCAP_F_SOFTWARE) &&
851 		    crypto_devallowsoft == 0)
852 			continue;
853 		if (crypto_drivers[hid].cc_kprocess == NULL)
854 			continue;
855 		if ((crypto_drivers[hid].cc_kalg[krp->krp_op] &
856 		    CRYPTO_ALG_FLAG_SUPPORTED) == 0)
857 			continue;
858 		break;
859 	}
860 	if (hid < crypto_drivers_num) {
861 		int (*process)(void *, struct cryptkop *, int);
862 		void *arg;
863 
864 		process = crypto_drivers[hid].cc_kprocess;
865 		arg = crypto_drivers[hid].cc_karg;
866 		mutex_exit(&crypto_mtx);
867 		krp->krp_hid = hid;
868 		error = (*process)(arg, krp, hint);
869 	} else {
870 		mutex_exit(&crypto_mtx);
871 		error = ENODEV;
872 	}
873 
874 	if (error) {
875 		krp->krp_status = error;
876 		crypto_kdone(krp);
877 	}
878 	return 0;
879 }
880 
881 #ifdef CRYPTO_TIMING
882 static void
883 crypto_tstat(struct cryptotstat *ts, struct timespec *tv)
884 {
885 	struct timespec now, t;
886 
887 	nanouptime(&now);
888 	t.tv_sec = now.tv_sec - tv->tv_sec;
889 	t.tv_nsec = now.tv_nsec - tv->tv_nsec;
890 	if (t.tv_nsec < 0) {
891 		t.tv_sec--;
892 		t.tv_nsec += 1000000000;
893 	}
894 	timespecadd(&ts->acc, &t, &t);
895 	if (timespeccmp(&t, &ts->min, <))
896 		ts->min = t;
897 	if (timespeccmp(&t, &ts->max, >))
898 		ts->max = t;
899 	ts->count++;
900 
901 	*tv = now;
902 }
903 #endif
904 
905 /*
906  * Dispatch a crypto request to the appropriate crypto devices.
907  */
908 static int
909 crypto_invoke(struct cryptop *crp, int hint)
910 {
911 	u_int32_t hid;
912 
913 #ifdef CRYPTO_TIMING
914 	if (crypto_timing)
915 		crypto_tstat(&cryptostats.cs_invoke, &crp->crp_tstamp);
916 #endif
917 	/* Sanity checks. */
918 	if (crp == NULL)
919 		return EINVAL;
920 	if (crp->crp_callback == NULL) {
921 		return EINVAL;
922 	}
923 	if (crp->crp_desc == NULL) {
924 		crp->crp_etype = EINVAL;
925 		crypto_done(crp);
926 		return 0;
927 	}
928 
929 	hid = CRYPTO_SESID2HID(crp->crp_sid);
930 
931 	if (hid < crypto_drivers_num) {
932 		int (*process)(void *, struct cryptop *, int);
933 		void *arg;
934 
935 		if (crypto_drivers[hid].cc_flags & CRYPTOCAP_F_CLEANUP) {
936 			mutex_exit(&crypto_mtx);
937 			crypto_freesession(crp->crp_sid);
938 			mutex_enter(&crypto_mtx);
939 		}
940 		process = crypto_drivers[hid].cc_process;
941 		arg = crypto_drivers[hid].cc_arg;
942 
943 		/*
944 		 * Invoke the driver to process the request.
945 		 */
946 		DPRINTF(("calling process for %p\n", crp));
947 		return (*process)(arg, crp, hint);
948 	} else {
949 		struct cryptodesc *crd;
950 		u_int64_t nid = 0;
951 
952 		/*
953 		 * Driver has unregistered; migrate the session and return
954 		 * an error to the caller so they'll resubmit the op.
955 		 */
956 		for (crd = crp->crp_desc; crd->crd_next; crd = crd->crd_next)
957 			crd->CRD_INI.cri_next = &(crd->crd_next->CRD_INI);
958 
959 		if (crypto_newsession(&nid, &(crp->crp_desc->CRD_INI), 0) == 0)
960 			crp->crp_sid = nid;
961 
962 		crp->crp_etype = EAGAIN;
963 
964 		crypto_done(crp);
965 		return 0;
966 	}
967 }
968 
969 /*
970  * Release a set of crypto descriptors.
971  */
972 void
973 crypto_freereq(struct cryptop *crp)
974 {
975 	struct cryptodesc *crd;
976 
977 	if (crp == NULL)
978 		return;
979 	DPRINTF(("crypto_freereq[%u]: crp %p\n",
980 		CRYPTO_SESID2LID(crp->crp_sid), crp));
981 
982 	/* sanity check */
983 	if (crp->crp_flags & CRYPTO_F_ONRETQ) {
984 		panic("crypto_freereq() freeing crp on RETQ\n");
985 	}
986 
987 	while ((crd = crp->crp_desc) != NULL) {
988 		crp->crp_desc = crd->crd_next;
989 		pool_put(&cryptodesc_pool, crd);
990 	}
991 	pool_put(&cryptop_pool, crp);
992 }
993 
994 /*
995  * Acquire a set of crypto descriptors.
996  */
997 struct cryptop *
998 crypto_getreq(int num)
999 {
1000 	struct cryptodesc *crd;
1001 	struct cryptop *crp;
1002 
1003 	crp = pool_get(&cryptop_pool, 0);
1004 	if (crp == NULL) {
1005 		return NULL;
1006 	}
1007 	memset(crp, 0, sizeof(struct cryptop));
1008 
1009 	while (num--) {
1010 		crd = pool_get(&cryptodesc_pool, 0);
1011 		if (crd == NULL) {
1012 			crypto_freereq(crp);
1013 			return NULL;
1014 		}
1015 
1016 		memset(crd, 0, sizeof(struct cryptodesc));
1017 		crd->crd_next = crp->crp_desc;
1018 		crp->crp_desc = crd;
1019 	}
1020 
1021 	return crp;
1022 }
1023 
1024 /*
1025  * Invoke the callback on behalf of the driver.
1026  */
1027 void
1028 crypto_done(struct cryptop *crp)
1029 {
1030 	int wasempty;
1031 
1032 	if (crp->crp_etype != 0)
1033 		cryptostats.cs_errs++;
1034 #ifdef CRYPTO_TIMING
1035 	if (crypto_timing)
1036 		crypto_tstat(&cryptostats.cs_done, &crp->crp_tstamp);
1037 #endif
1038 	DPRINTF(("crypto_done[%u]: crp %p\n",
1039 		CRYPTO_SESID2LID(crp->crp_sid), crp));
1040 
1041 	/*
1042 	 * Normal case; queue the callback for the thread.
1043 	 *
1044 	 * The return queue is manipulated by the swi thread
1045 	 * and, potentially, by crypto device drivers calling
1046 	 * back to mark operations completed.  Thus we need
1047 	 * to mask both while manipulating the return queue.
1048 	 */
1049   	if (crp->crp_flags & CRYPTO_F_CBIMM) {
1050 		/*
1051 	 	* Do the callback directly.  This is ok when the
1052   	 	* callback routine does very little (e.g. the
1053 	 	* /dev/crypto callback method just does a wakeup).
1054 	 	*/
1055 		mutex_spin_enter(&crypto_ret_q_mtx);
1056 		crp->crp_flags |= CRYPTO_F_DONE;
1057 		mutex_spin_exit(&crypto_ret_q_mtx);
1058 
1059 #ifdef CRYPTO_TIMING
1060 		if (crypto_timing) {
1061 			/*
1062 		 	* NB: We must copy the timestamp before
1063 		 	* doing the callback as the cryptop is
1064 		 	* likely to be reclaimed.
1065 		 	*/
1066 			struct timespec t = crp->crp_tstamp;
1067 			crypto_tstat(&cryptostats.cs_cb, &t);
1068 			crp->crp_callback(crp);
1069 			crypto_tstat(&cryptostats.cs_finis, &t);
1070 		} else
1071 #endif
1072 		crp->crp_callback(crp);
1073 	} else {
1074 		mutex_spin_enter(&crypto_ret_q_mtx);
1075 		crp->crp_flags |= CRYPTO_F_DONE;
1076 
1077 		if (crp->crp_flags & CRYPTO_F_USER) {
1078 			/* the request has completed while
1079 			 * running in the user context
1080 			 * so don't queue it - the user
1081 			 * thread won't sleep when it sees
1082 			 * the CRYPTO_F_DONE flag.
1083 			 * This is an optimization to avoid
1084 			 * unecessary context switches.
1085 			 */
1086 			DPRINTF(("crypto_done[%u]: crp %p CRYPTO_F_USER\n",
1087 				CRYPTO_SESID2LID(crp->crp_sid), crp));
1088 		} else {
1089 			wasempty = TAILQ_EMPTY(&crp_ret_q);
1090 			DPRINTF(("crypto_done[%u]: queueing %p\n",
1091 				CRYPTO_SESID2LID(crp->crp_sid), crp));
1092 			crp->crp_flags |= CRYPTO_F_ONRETQ;
1093 			TAILQ_INSERT_TAIL(&crp_ret_q, crp, crp_next);
1094 			if (wasempty) {
1095 				DPRINTF(("crypto_done[%u]: waking cryptoret, "
1096 					"crp %p hit empty queue\n.",
1097 					CRYPTO_SESID2LID(crp->crp_sid), crp));
1098 				cv_signal(&cryptoret_cv);
1099 			}
1100 		}
1101 		mutex_spin_exit(&crypto_ret_q_mtx);
1102 	}
1103 }
1104 
1105 /*
1106  * Invoke the callback on behalf of the driver.
1107  */
1108 void
1109 crypto_kdone(struct cryptkop *krp)
1110 {
1111 	int wasempty;
1112 
1113 	if (krp->krp_status != 0)
1114 		cryptostats.cs_kerrs++;
1115 
1116 	krp->krp_flags |= CRYPTO_F_DONE;
1117 
1118 	/*
1119 	 * The return queue is manipulated by the swi thread
1120 	 * and, potentially, by crypto device drivers calling
1121 	 * back to mark operations completed.  Thus we need
1122 	 * to mask both while manipulating the return queue.
1123 	 */
1124 	if (krp->krp_flags & CRYPTO_F_CBIMM) {
1125 		krp->krp_callback(krp);
1126 	} else {
1127 		mutex_spin_enter(&crypto_ret_q_mtx);
1128 		wasempty = TAILQ_EMPTY(&crp_ret_kq);
1129 		krp->krp_flags |= CRYPTO_F_ONRETQ;
1130 		TAILQ_INSERT_TAIL(&crp_ret_kq, krp, krp_next);
1131 		if (wasempty)
1132 			cv_signal(&cryptoret_cv);
1133 		mutex_spin_exit(&crypto_ret_q_mtx);
1134 	}
1135 }
1136 
1137 int
1138 crypto_getfeat(int *featp)
1139 {
1140 	int hid, kalg, feat = 0;
1141 
1142 	mutex_enter(&crypto_mtx);
1143 
1144 	if (crypto_userasymcrypto == 0)
1145 		goto out;
1146 
1147 	for (hid = 0; hid < crypto_drivers_num; hid++) {
1148 		if ((crypto_drivers[hid].cc_flags & CRYPTOCAP_F_SOFTWARE) &&
1149 		    crypto_devallowsoft == 0) {
1150 			continue;
1151 		}
1152 		if (crypto_drivers[hid].cc_kprocess == NULL)
1153 			continue;
1154 		for (kalg = 0; kalg < CRK_ALGORITHM_MAX; kalg++)
1155 			if ((crypto_drivers[hid].cc_kalg[kalg] &
1156 			    CRYPTO_ALG_FLAG_SUPPORTED) != 0)
1157 				feat |=  1 << kalg;
1158 	}
1159 out:
1160 	mutex_exit(&crypto_mtx);
1161 	*featp = feat;
1162 	return (0);
1163 }
1164 
1165 /*
1166  * Software interrupt thread to dispatch crypto requests.
1167  */
1168 static void
1169 cryptointr(void)
1170 {
1171 	struct cryptop *crp, *submit, *cnext;
1172 	struct cryptkop *krp, *knext;
1173 	struct cryptocap *cap;
1174 	int result, hint;
1175 
1176 	cryptostats.cs_intrs++;
1177 	mutex_spin_enter(&crypto_q_mtx);
1178 	do {
1179 		/*
1180 		 * Find the first element in the queue that can be
1181 		 * processed and look-ahead to see if multiple ops
1182 		 * are ready for the same driver.
1183 		 */
1184 		submit = NULL;
1185 		hint = 0;
1186 		TAILQ_FOREACH_SAFE(crp, &crp_q, crp_next, cnext) {
1187 			u_int32_t hid = CRYPTO_SESID2HID(crp->crp_sid);
1188 			cap = crypto_checkdriver(hid);
1189 			if (cap == NULL || cap->cc_process == NULL) {
1190 				/* Op needs to be migrated, process it. */
1191 				if (submit == NULL)
1192 					submit = crp;
1193 				break;
1194 			}
1195 			if (!cap->cc_qblocked) {
1196 				if (submit != NULL) {
1197 					/*
1198 					 * We stop on finding another op,
1199 					 * regardless whether its for the same
1200 					 * driver or not.  We could keep
1201 					 * searching the queue but it might be
1202 					 * better to just use a per-driver
1203 					 * queue instead.
1204 					 */
1205 					if (CRYPTO_SESID2HID(submit->crp_sid)
1206 					    == hid)
1207 						hint = CRYPTO_HINT_MORE;
1208 					break;
1209 				} else {
1210 					submit = crp;
1211 					if ((submit->crp_flags & CRYPTO_F_BATCH) == 0)
1212 						break;
1213 					/* keep scanning for more are q'd */
1214 				}
1215 			}
1216 		}
1217 		if (submit != NULL) {
1218 			TAILQ_REMOVE(&crp_q, submit, crp_next);
1219 			mutex_spin_exit(&crypto_q_mtx);
1220 			result = crypto_invoke(submit, hint);
1221 			/* we must take here as the TAILQ op or kinvoke
1222 			   may need this mutex below.  sigh. */
1223 			mutex_spin_enter(&crypto_q_mtx);
1224 			if (result == ERESTART) {
1225 				/*
1226 				 * The driver ran out of resources, mark the
1227 				 * driver ``blocked'' for cryptop's and put
1228 				 * the request back in the queue.  It would
1229 				 * best to put the request back where we got
1230 				 * it but that's hard so for now we put it
1231 				 * at the front.  This should be ok; putting
1232 				 * it at the end does not work.
1233 				 */
1234 				/* XXX validate sid again? */
1235 				crypto_drivers[CRYPTO_SESID2HID(submit->crp_sid)].cc_qblocked = 1;
1236 				TAILQ_INSERT_HEAD(&crp_q, submit, crp_next);
1237 				cryptostats.cs_blocks++;
1238 			}
1239 		}
1240 
1241 		/* As above, but for key ops */
1242 		TAILQ_FOREACH_SAFE(krp, &crp_kq, krp_next, knext) {
1243 			cap = crypto_checkdriver(krp->krp_hid);
1244 			if (cap == NULL || cap->cc_kprocess == NULL) {
1245 				/* Op needs to be migrated, process it. */
1246 				break;
1247 			}
1248 			if (!cap->cc_kqblocked)
1249 				break;
1250 		}
1251 		if (krp != NULL) {
1252 			TAILQ_REMOVE(&crp_kq, krp, krp_next);
1253 			mutex_spin_exit(&crypto_q_mtx);
1254 			result = crypto_kinvoke(krp, 0);
1255 			/* the next iteration will want the mutex. :-/ */
1256 			mutex_spin_enter(&crypto_q_mtx);
1257 			if (result == ERESTART) {
1258 				/*
1259 				 * The driver ran out of resources, mark the
1260 				 * driver ``blocked'' for cryptkop's and put
1261 				 * the request back in the queue.  It would
1262 				 * best to put the request back where we got
1263 				 * it but that's hard so for now we put it
1264 				 * at the front.  This should be ok; putting
1265 				 * it at the end does not work.
1266 				 */
1267 				/* XXX validate sid again? */
1268 				crypto_drivers[krp->krp_hid].cc_kqblocked = 1;
1269 				TAILQ_INSERT_HEAD(&crp_kq, krp, krp_next);
1270 				cryptostats.cs_kblocks++;
1271 			}
1272 		}
1273 	} while (submit != NULL || krp != NULL);
1274 	mutex_spin_exit(&crypto_q_mtx);
1275 }
1276 
1277 /*
1278  * Kernel thread to do callbacks.
1279  */
1280 static void
1281 cryptoret(void)
1282 {
1283 	struct cryptop *crp;
1284 	struct cryptkop *krp;
1285 
1286 	mutex_spin_enter(&crypto_ret_q_mtx);
1287 	for (;;) {
1288 		crp = TAILQ_FIRST(&crp_ret_q);
1289 		if (crp != NULL) {
1290 			TAILQ_REMOVE(&crp_ret_q, crp, crp_next);
1291 			crp->crp_flags &= ~CRYPTO_F_ONRETQ;
1292 		}
1293 		krp = TAILQ_FIRST(&crp_ret_kq);
1294 		if (krp != NULL) {
1295 			TAILQ_REMOVE(&crp_ret_kq, krp, krp_next);
1296 			krp->krp_flags &= ~CRYPTO_F_ONRETQ;
1297 		}
1298 
1299 		/* drop before calling any callbacks. */
1300 		if (crp == NULL && krp == NULL) {
1301 			cryptostats.cs_rets++;
1302 			cv_wait(&cryptoret_cv, &crypto_ret_q_mtx);
1303 			continue;
1304 		}
1305 
1306 		mutex_spin_exit(&crypto_ret_q_mtx);
1307 
1308 		if (crp != NULL) {
1309 #ifdef CRYPTO_TIMING
1310 			if (crypto_timing) {
1311 				/*
1312 				 * NB: We must copy the timestamp before
1313 				 * doing the callback as the cryptop is
1314 				 * likely to be reclaimed.
1315 				 */
1316 				struct timespec t = crp->crp_tstamp;
1317 				crypto_tstat(&cryptostats.cs_cb, &t);
1318 				crp->crp_callback(crp);
1319 				crypto_tstat(&cryptostats.cs_finis, &t);
1320 			} else
1321 #endif
1322 			{
1323 				crp->crp_callback(crp);
1324 			}
1325 		}
1326 		if (krp != NULL)
1327 			krp->krp_callback(krp);
1328 
1329 		mutex_spin_enter(&crypto_ret_q_mtx);
1330 	}
1331 }
1332