xref: /netbsd-src/sys/opencrypto/crypto.c (revision b7b7574d3bf8eeb51a1fa3977b59142ec6434a55)
1 /*	$NetBSD: crypto.c,v 1.45 2014/02/25 18:30:12 pooka 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 1.45 2014/02/25 18:30:12 pooka 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 #include <sys/errno.h>
69 #include <sys/module.h>
70 
71 #if defined(_KERNEL_OPT)
72 #include "opt_ocf.h"
73 #endif
74 
75 #include <opencrypto/cryptodev.h>
76 #include <opencrypto/xform.h>			/* XXX for M_XDATA */
77 
78 kmutex_t crypto_q_mtx;
79 kmutex_t crypto_ret_q_mtx;
80 kcondvar_t cryptoret_cv;
81 kmutex_t crypto_mtx;
82 
83 /* below are kludges for residual code wrtitten to FreeBSD interfaces */
84   #define SWI_CRYPTO 17
85   #define register_swi(lvl, fn)  \
86   softint_establish(SOFTINT_NET|SOFTINT_MPSAFE, (void (*)(void *))fn, NULL)
87   #define unregister_swi(lvl, fn)  softint_disestablish(softintr_cookie)
88   #define setsoftcrypto(x) softint_schedule(x)
89 
90 int crypto_ret_q_check(struct cryptop *);
91 
92 /*
93  * Crypto drivers register themselves by allocating a slot in the
94  * crypto_drivers table with crypto_get_driverid() and then registering
95  * each algorithm they support with crypto_register() and crypto_kregister().
96  */
97 static	struct cryptocap *crypto_drivers;
98 static	int crypto_drivers_num;
99 static	void *softintr_cookie;
100 
101 /*
102  * There are two queues for crypto requests; one for symmetric (e.g.
103  * cipher) operations and one for asymmetric (e.g. MOD) operations.
104  * See below for how synchronization is handled.
105  */
106 static	TAILQ_HEAD(,cryptop) crp_q =		/* request queues */
107 		TAILQ_HEAD_INITIALIZER(crp_q);
108 static	TAILQ_HEAD(,cryptkop) crp_kq =
109 		TAILQ_HEAD_INITIALIZER(crp_kq);
110 
111 /*
112  * There are two queues for processing completed crypto requests; one
113  * for the symmetric and one for the asymmetric ops.  We only need one
114  * but have two to avoid type futzing (cryptop vs. cryptkop).  See below
115  * for how synchronization is handled.
116  */
117 static	TAILQ_HEAD(crprethead, cryptop) crp_ret_q =	/* callback queues */
118 		TAILQ_HEAD_INITIALIZER(crp_ret_q);
119 static	TAILQ_HEAD(krprethead, cryptkop) crp_ret_kq =
120 		TAILQ_HEAD_INITIALIZER(crp_ret_kq);
121 
122 /*
123  * XXX these functions are ghastly hacks for when the submission
124  * XXX routines discover a request that was not CBIMM is already
125  * XXX done, and must be yanked from the retq (where _done) put it
126  * XXX as cryptoret won't get the chance.  The queue is walked backwards
127  * XXX as the request is generally the last one queued.
128  *
129  *	 call with the lock held, or else.
130  */
131 int
132 crypto_ret_q_remove(struct cryptop *crp)
133 {
134 	struct cryptop * acrp, *next;
135 
136 	TAILQ_FOREACH_REVERSE_SAFE(acrp, &crp_ret_q, crprethead, crp_next, next) {
137 		if (acrp == crp) {
138 			TAILQ_REMOVE(&crp_ret_q, crp, crp_next);
139 			crp->crp_flags &= (~CRYPTO_F_ONRETQ);
140 			return 1;
141 		}
142 	}
143 	return 0;
144 }
145 
146 int
147 crypto_ret_kq_remove(struct cryptkop *krp)
148 {
149 	struct cryptkop * akrp, *next;
150 
151 	TAILQ_FOREACH_REVERSE_SAFE(akrp, &crp_ret_kq, krprethead, krp_next, next) {
152 		if (akrp == krp) {
153 			TAILQ_REMOVE(&crp_ret_kq, krp, krp_next);
154 			krp->krp_flags &= (~CRYPTO_F_ONRETQ);
155 			return 1;
156 		}
157 	}
158 	return 0;
159 }
160 
161 /*
162  * Crypto op and desciptor data structures are allocated
163  * from separate private zones(FreeBSD)/pools(netBSD/OpenBSD) .
164  */
165 struct pool cryptop_pool;
166 struct pool cryptodesc_pool;
167 struct pool cryptkop_pool;
168 
169 int	crypto_usercrypto = 1;		/* userland may open /dev/crypto */
170 int	crypto_userasymcrypto = 1;	/* userland may do asym crypto reqs */
171 /*
172  * cryptodevallowsoft is (intended to be) sysctl'able, controlling
173  * access to hardware versus software transforms as below:
174  *
175  * crypto_devallowsoft < 0:  Force userlevel requests to use software
176  *                              transforms, always
177  * crypto_devallowsoft = 0:  Use hardware if present, grant userlevel
178  *                              requests for non-accelerated transforms
179  *                              (handling the latter in software)
180  * crypto_devallowsoft > 0:  Allow user requests only for transforms which
181  *                               are hardware-accelerated.
182  */
183 int	crypto_devallowsoft = 1;	/* only use hardware crypto */
184 
185 SYSCTL_SETUP(sysctl_opencrypto_setup, "sysctl opencrypto subtree setup")
186 {
187 
188 	sysctl_createv(clog, 0, NULL, NULL,
189 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
190 		       CTLTYPE_INT, "usercrypto",
191 		       SYSCTL_DESCR("Enable/disable user-mode access to "
192 			   "crypto support"),
193 		       NULL, 0, &crypto_usercrypto, 0,
194 		       CTL_KERN, CTL_CREATE, CTL_EOL);
195 	sysctl_createv(clog, 0, NULL, NULL,
196 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
197 		       CTLTYPE_INT, "userasymcrypto",
198 		       SYSCTL_DESCR("Enable/disable user-mode access to "
199 			   "asymmetric crypto support"),
200 		       NULL, 0, &crypto_userasymcrypto, 0,
201 		       CTL_KERN, CTL_CREATE, CTL_EOL);
202 	sysctl_createv(clog, 0, NULL, NULL,
203 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
204 		       CTLTYPE_INT, "cryptodevallowsoft",
205 		       SYSCTL_DESCR("Enable/disable use of software "
206 			   "asymmetric crypto support"),
207 		       NULL, 0, &crypto_devallowsoft, 0,
208 		       CTL_KERN, CTL_CREATE, CTL_EOL);
209 }
210 
211 MALLOC_DEFINE(M_CRYPTO_DATA, "crypto", "crypto session records");
212 
213 /*
214  * Synchronization: read carefully, this is non-trivial.
215  *
216  * Crypto requests are submitted via crypto_dispatch.  Typically
217  * these come in from network protocols at spl0 (output path) or
218  * spl[,soft]net (input path).
219  *
220  * Requests are typically passed on the driver directly, but they
221  * may also be queued for processing by a software interrupt thread,
222  * cryptointr, that runs at splsoftcrypto.  This thread dispatches
223  * the requests to crypto drivers (h/w or s/w) who call crypto_done
224  * when a request is complete.  Hardware crypto drivers are assumed
225  * to register their IRQ's as network devices so their interrupt handlers
226  * and subsequent "done callbacks" happen at spl[imp,net].
227  *
228  * Completed crypto ops are queued for a separate kernel thread that
229  * handles the callbacks at spl0.  This decoupling insures the crypto
230  * driver interrupt service routine is not delayed while the callback
231  * takes place and that callbacks are delivered after a context switch
232  * (as opposed to a software interrupt that clients must block).
233  *
234  * This scheme is not intended for SMP machines.
235  */
236 static	void cryptointr(void);		/* swi thread to dispatch ops */
237 static	void cryptoret(void);		/* kernel thread for callbacks*/
238 static	struct lwp *cryptothread;
239 static	void crypto_destroy(void);
240 static	int crypto_invoke(struct cryptop *crp, int hint);
241 static	int crypto_kinvoke(struct cryptkop *krp, int hint);
242 
243 static struct cryptostats cryptostats;
244 #ifdef CRYPTO_TIMING
245 static	int crypto_timing = 0;
246 #endif
247 
248 #ifdef _MODULE
249 	static struct sysctllog *sysctl_opencrypto_clog;
250 #endif
251 
252 static int
253 crypto_init0(void)
254 {
255 	int error;
256 
257 	mutex_init(&crypto_mtx, MUTEX_DEFAULT, IPL_NONE);
258 	mutex_init(&crypto_q_mtx, MUTEX_DEFAULT, IPL_NET);
259 	mutex_init(&crypto_ret_q_mtx, MUTEX_DEFAULT, IPL_NET);
260 	cv_init(&cryptoret_cv, "crypto_w");
261 	pool_init(&cryptop_pool, sizeof(struct cryptop), 0, 0,
262 		  0, "cryptop", NULL, IPL_NET);
263 	pool_init(&cryptodesc_pool, sizeof(struct cryptodesc), 0, 0,
264 		  0, "cryptodesc", NULL, IPL_NET);
265 	pool_init(&cryptkop_pool, sizeof(struct cryptkop), 0, 0,
266 		  0, "cryptkop", NULL, IPL_NET);
267 
268 	crypto_drivers = malloc(CRYPTO_DRIVERS_INITIAL *
269 	    sizeof(struct cryptocap), M_CRYPTO_DATA, M_NOWAIT | M_ZERO);
270 	if (crypto_drivers == NULL) {
271 		printf("crypto_init: cannot malloc driver table\n");
272 		return 0;
273 	}
274 	crypto_drivers_num = CRYPTO_DRIVERS_INITIAL;
275 
276 	softintr_cookie = register_swi(SWI_CRYPTO, cryptointr);
277 	error = kthread_create(PRI_NONE, KTHREAD_MPSAFE, NULL,
278 	    (void (*)(void *))cryptoret, NULL, &cryptothread, "cryptoret");
279 	if (error) {
280 		printf("crypto_init: cannot start cryptoret thread; error %d",
281 			error);
282 		crypto_destroy();
283 	}
284 
285 #ifdef _MODULE
286 	sysctl_opencrypto_setup(&sysctl_opencrypto_clog);
287 #endif
288 	return 0;
289 }
290 
291 void
292 crypto_init(void)
293 {
294 	static ONCE_DECL(crypto_init_once);
295 
296 	RUN_ONCE(&crypto_init_once, crypto_init0);
297 }
298 
299 static void
300 crypto_destroy(void)
301 {
302 	/* XXX no wait to reclaim zones */
303 	if (crypto_drivers != NULL)
304 		free(crypto_drivers, M_CRYPTO_DATA);
305 	unregister_swi(SWI_CRYPTO, cryptointr);
306 }
307 
308 /*
309  * Create a new session.  Must be called with crypto_mtx held.
310  */
311 int
312 crypto_newsession(u_int64_t *sid, struct cryptoini *cri, int hard)
313 {
314 	struct cryptoini *cr;
315 	u_int32_t hid, lid;
316 	int err = EINVAL;
317 
318 	mutex_enter(&crypto_mtx);
319 
320 	if (crypto_drivers == NULL)
321 		goto done;
322 
323 	/*
324 	 * The algorithm we use here is pretty stupid; just use the
325 	 * first driver that supports all the algorithms we need.
326 	 *
327 	 * XXX We need more smarts here (in real life too, but that's
328 	 * XXX another story altogether).
329 	 */
330 
331 	for (hid = 0; hid < crypto_drivers_num; hid++) {
332 		/*
333 		 * If it's not initialized or has remaining sessions
334 		 * referencing it, skip.
335 		 */
336 		if (crypto_drivers[hid].cc_newsession == NULL ||
337 		    (crypto_drivers[hid].cc_flags & CRYPTOCAP_F_CLEANUP))
338 			continue;
339 
340 		/* Hardware required -- ignore software drivers. */
341 		if (hard > 0 &&
342 		    (crypto_drivers[hid].cc_flags & CRYPTOCAP_F_SOFTWARE))
343 			continue;
344 		/* Software required -- ignore hardware drivers. */
345 		if (hard < 0 &&
346 		    (crypto_drivers[hid].cc_flags & CRYPTOCAP_F_SOFTWARE) == 0)
347 			continue;
348 
349 		/* See if all the algorithms are supported. */
350 		for (cr = cri; cr; cr = cr->cri_next)
351 			if (crypto_drivers[hid].cc_alg[cr->cri_alg] == 0) {
352 				DPRINTF(("crypto_newsession: alg %d not supported\n", cr->cri_alg));
353 				break;
354 			}
355 
356 		if (cr == NULL) {
357 			/* Ok, all algorithms are supported. */
358 
359 			/*
360 			 * Can't do everything in one session.
361 			 *
362 			 * XXX Fix this. We need to inject a "virtual" session layer right
363 			 * XXX about here.
364 			 */
365 
366 			/* Call the driver initialization routine. */
367 			lid = hid;		/* Pass the driver ID. */
368 			err = crypto_drivers[hid].cc_newsession(
369 					crypto_drivers[hid].cc_arg, &lid, cri);
370 			if (err == 0) {
371 				(*sid) = hid;
372 				(*sid) <<= 32;
373 				(*sid) |= (lid & 0xffffffff);
374 				crypto_drivers[hid].cc_sessions++;
375 			}
376 			goto done;
377 			/*break;*/
378 		}
379 	}
380 done:
381 	mutex_exit(&crypto_mtx);
382 	return err;
383 }
384 
385 /*
386  * Delete an existing session (or a reserved session on an unregistered
387  * driver).  Must be called with crypto_mtx mutex held.
388  */
389 int
390 crypto_freesession(u_int64_t sid)
391 {
392 	u_int32_t hid;
393 	int err = 0;
394 
395 	mutex_enter(&crypto_mtx);
396 
397 	if (crypto_drivers == NULL) {
398 		err = EINVAL;
399 		goto done;
400 	}
401 
402 	/* Determine two IDs. */
403 	hid = CRYPTO_SESID2HID(sid);
404 
405 	if (hid >= crypto_drivers_num) {
406 		err = ENOENT;
407 		goto done;
408 	}
409 
410 	if (crypto_drivers[hid].cc_sessions)
411 		crypto_drivers[hid].cc_sessions--;
412 
413 	/* Call the driver cleanup routine, if available. */
414 	if (crypto_drivers[hid].cc_freesession) {
415 		err = crypto_drivers[hid].cc_freesession(
416 				crypto_drivers[hid].cc_arg, sid);
417 	}
418 	else
419 		err = 0;
420 
421 	/*
422 	 * If this was the last session of a driver marked as invalid,
423 	 * make the entry available for reuse.
424 	 */
425 	if ((crypto_drivers[hid].cc_flags & CRYPTOCAP_F_CLEANUP) &&
426 	    crypto_drivers[hid].cc_sessions == 0)
427 		memset(&crypto_drivers[hid], 0, sizeof(struct cryptocap));
428 
429 done:
430 	mutex_exit(&crypto_mtx);
431 	return err;
432 }
433 
434 /*
435  * Return an unused driver id.  Used by drivers prior to registering
436  * support for the algorithms they handle.
437  */
438 int32_t
439 crypto_get_driverid(u_int32_t flags)
440 {
441 	struct cryptocap *newdrv;
442 	int i;
443 
444 	crypto_init();		/* XXX oh, this is foul! */
445 
446 	mutex_enter(&crypto_mtx);
447 	for (i = 0; i < crypto_drivers_num; i++)
448 		if (crypto_drivers[i].cc_process == NULL &&
449 		    (crypto_drivers[i].cc_flags & CRYPTOCAP_F_CLEANUP) == 0 &&
450 		    crypto_drivers[i].cc_sessions == 0)
451 			break;
452 
453 	/* Out of entries, allocate some more. */
454 	if (i == crypto_drivers_num) {
455 		/* Be careful about wrap-around. */
456 		if (2 * crypto_drivers_num <= crypto_drivers_num) {
457 			mutex_exit(&crypto_mtx);
458 			printf("crypto: driver count wraparound!\n");
459 			return -1;
460 		}
461 
462 		newdrv = malloc(2 * crypto_drivers_num *
463 		    sizeof(struct cryptocap), M_CRYPTO_DATA, M_NOWAIT|M_ZERO);
464 		if (newdrv == NULL) {
465 			mutex_exit(&crypto_mtx);
466 			printf("crypto: no space to expand driver table!\n");
467 			return -1;
468 		}
469 
470 		memcpy(newdrv, crypto_drivers,
471 		    crypto_drivers_num * sizeof(struct cryptocap));
472 
473 		crypto_drivers_num *= 2;
474 
475 		free(crypto_drivers, M_CRYPTO_DATA);
476 		crypto_drivers = newdrv;
477 	}
478 
479 	/* NB: state is zero'd on free */
480 	crypto_drivers[i].cc_sessions = 1;	/* Mark */
481 	crypto_drivers[i].cc_flags = flags;
482 
483 	if (bootverbose)
484 		printf("crypto: assign driver %u, flags %u\n", i, flags);
485 
486 	mutex_exit(&crypto_mtx);
487 
488 	return i;
489 }
490 
491 static struct cryptocap *
492 crypto_checkdriver(u_int32_t hid)
493 {
494 	if (crypto_drivers == NULL)
495 		return NULL;
496 	return (hid >= crypto_drivers_num ? NULL : &crypto_drivers[hid]);
497 }
498 
499 /*
500  * Register support for a key-related algorithm.  This routine
501  * is called once for each algorithm supported a driver.
502  */
503 int
504 crypto_kregister(u_int32_t driverid, int kalg, u_int32_t flags,
505     int (*kprocess)(void *, struct cryptkop *, int),
506     void *karg)
507 {
508 	struct cryptocap *cap;
509 	int err;
510 
511 	mutex_enter(&crypto_mtx);
512 
513 	cap = crypto_checkdriver(driverid);
514 	if (cap != NULL &&
515 	    (CRK_ALGORITM_MIN <= kalg && kalg <= CRK_ALGORITHM_MAX)) {
516 		/*
517 		 * XXX Do some performance testing to determine placing.
518 		 * XXX We probably need an auxiliary data structure that
519 		 * XXX describes relative performances.
520 		 */
521 
522 		cap->cc_kalg[kalg] = flags | CRYPTO_ALG_FLAG_SUPPORTED;
523 		if (bootverbose) {
524 			printf("crypto: driver %u registers key alg %u "
525 			       " flags %u\n",
526 				driverid,
527 				kalg,
528 				flags
529 			);
530 		}
531 
532 		if (cap->cc_kprocess == NULL) {
533 			cap->cc_karg = karg;
534 			cap->cc_kprocess = kprocess;
535 		}
536 		err = 0;
537 	} else
538 		err = EINVAL;
539 
540 	mutex_exit(&crypto_mtx);
541 	return err;
542 }
543 
544 /*
545  * Register support for a non-key-related algorithm.  This routine
546  * is called once for each such algorithm supported by a driver.
547  */
548 int
549 crypto_register(u_int32_t driverid, int alg, u_int16_t maxoplen,
550     u_int32_t flags,
551     int (*newses)(void *, u_int32_t*, struct cryptoini*),
552     int (*freeses)(void *, u_int64_t),
553     int (*process)(void *, struct cryptop *, int),
554     void *arg)
555 {
556 	struct cryptocap *cap;
557 	int err;
558 
559 	mutex_enter(&crypto_mtx);
560 
561 	cap = crypto_checkdriver(driverid);
562 	/* NB: algorithms are in the range [1..max] */
563 	if (cap != NULL &&
564 	    (CRYPTO_ALGORITHM_MIN <= alg && alg <= CRYPTO_ALGORITHM_MAX)) {
565 		/*
566 		 * XXX Do some performance testing to determine placing.
567 		 * XXX We probably need an auxiliary data structure that
568 		 * XXX describes relative performances.
569 		 */
570 
571 		cap->cc_alg[alg] = flags | CRYPTO_ALG_FLAG_SUPPORTED;
572 		cap->cc_max_op_len[alg] = maxoplen;
573 		if (bootverbose) {
574 			printf("crypto: driver %u registers alg %u "
575 				"flags %u maxoplen %u\n",
576 				driverid,
577 				alg,
578 				flags,
579 				maxoplen
580 			);
581 		}
582 
583 		if (cap->cc_process == NULL) {
584 			cap->cc_arg = arg;
585 			cap->cc_newsession = newses;
586 			cap->cc_process = process;
587 			cap->cc_freesession = freeses;
588 			cap->cc_sessions = 0;		/* Unmark */
589 		}
590 		err = 0;
591 	} else
592 		err = EINVAL;
593 
594 	mutex_exit(&crypto_mtx);
595 	return err;
596 }
597 
598 /*
599  * Unregister a crypto driver. If there are pending sessions using it,
600  * leave enough information around so that subsequent calls using those
601  * sessions will correctly detect the driver has been unregistered and
602  * reroute requests.
603  */
604 int
605 crypto_unregister(u_int32_t driverid, int alg)
606 {
607 	int i, err;
608 	u_int32_t ses;
609 	struct cryptocap *cap;
610 
611 	mutex_enter(&crypto_mtx);
612 
613 	cap = crypto_checkdriver(driverid);
614 	if (cap != NULL &&
615 	    (CRYPTO_ALGORITHM_MIN <= alg && alg <= CRYPTO_ALGORITHM_MAX) &&
616 	    cap->cc_alg[alg] != 0) {
617 		cap->cc_alg[alg] = 0;
618 		cap->cc_max_op_len[alg] = 0;
619 
620 		/* Was this the last algorithm ? */
621 		for (i = 1; i <= CRYPTO_ALGORITHM_MAX; i++)
622 			if (cap->cc_alg[i] != 0)
623 				break;
624 
625 		if (i == CRYPTO_ALGORITHM_MAX + 1) {
626 			ses = cap->cc_sessions;
627 			memset(cap, 0, sizeof(struct cryptocap));
628 			if (ses != 0) {
629 				/*
630 				 * If there are pending sessions, just mark as invalid.
631 				 */
632 				cap->cc_flags |= CRYPTOCAP_F_CLEANUP;
633 				cap->cc_sessions = ses;
634 			}
635 		}
636 		err = 0;
637 	} else
638 		err = EINVAL;
639 
640 	mutex_exit(&crypto_mtx);
641 	return err;
642 }
643 
644 /*
645  * Unregister all algorithms associated with a crypto driver.
646  * If there are pending sessions using it, leave enough information
647  * around so that subsequent calls using those sessions will
648  * correctly detect the driver has been unregistered and reroute
649  * requests.
650  *
651  * XXX careful.  Don't change this to call crypto_unregister() for each
652  * XXX registered algorithm unless you drop the mutex across the calls;
653  * XXX you can't take it recursively.
654  */
655 int
656 crypto_unregister_all(u_int32_t driverid)
657 {
658 	int i, err;
659 	u_int32_t ses;
660 	struct cryptocap *cap;
661 
662 	mutex_enter(&crypto_mtx);
663 	cap = crypto_checkdriver(driverid);
664 	if (cap != NULL) {
665 		for (i = CRYPTO_ALGORITHM_MIN; i <= CRYPTO_ALGORITHM_MAX; i++) {
666 			cap->cc_alg[i] = 0;
667 			cap->cc_max_op_len[i] = 0;
668 		}
669 		ses = cap->cc_sessions;
670 		memset(cap, 0, sizeof(struct cryptocap));
671 		if (ses != 0) {
672 			/*
673 			 * If there are pending sessions, just mark as invalid.
674 			 */
675 			cap->cc_flags |= CRYPTOCAP_F_CLEANUP;
676 			cap->cc_sessions = ses;
677 		}
678 		err = 0;
679 	} else
680 		err = EINVAL;
681 
682 	mutex_exit(&crypto_mtx);
683 	return err;
684 }
685 
686 /*
687  * Clear blockage on a driver.  The what parameter indicates whether
688  * the driver is now ready for cryptop's and/or cryptokop's.
689  */
690 int
691 crypto_unblock(u_int32_t driverid, int what)
692 {
693 	struct cryptocap *cap;
694 	int needwakeup, err;
695 
696 	mutex_spin_enter(&crypto_q_mtx);
697 	cap = crypto_checkdriver(driverid);
698 	if (cap != NULL) {
699 		needwakeup = 0;
700 		if (what & CRYPTO_SYMQ) {
701 			needwakeup |= cap->cc_qblocked;
702 			cap->cc_qblocked = 0;
703 		}
704 		if (what & CRYPTO_ASYMQ) {
705 			needwakeup |= cap->cc_kqblocked;
706 			cap->cc_kqblocked = 0;
707 		}
708 		err = 0;
709 		if (needwakeup)
710 			setsoftcrypto(softintr_cookie);
711 		mutex_spin_exit(&crypto_q_mtx);
712 	} else {
713 		err = EINVAL;
714 		mutex_spin_exit(&crypto_q_mtx);
715 	}
716 
717 	return err;
718 }
719 
720 /*
721  * Dispatch a crypto request to a driver or queue
722  * it, to be processed by the kernel thread.
723  */
724 int
725 crypto_dispatch(struct cryptop *crp)
726 {
727 	u_int32_t hid = CRYPTO_SESID2HID(crp->crp_sid);
728 	int result;
729 
730 	mutex_spin_enter(&crypto_q_mtx);
731 	DPRINTF(("crypto_dispatch: crp %p, alg %d\n",
732 		crp, crp->crp_desc->crd_alg));
733 
734 	cryptostats.cs_ops++;
735 
736 #ifdef CRYPTO_TIMING
737 	if (crypto_timing)
738 		nanouptime(&crp->crp_tstamp);
739 #endif
740 	if ((crp->crp_flags & CRYPTO_F_BATCH) == 0) {
741 		struct cryptocap *cap;
742 		/*
743 		 * Caller marked the request to be processed
744 		 * immediately; dispatch it directly to the
745 		 * driver unless the driver is currently blocked.
746 		 */
747 		cap = crypto_checkdriver(hid);
748 		if (cap && !cap->cc_qblocked) {
749 			mutex_spin_exit(&crypto_q_mtx);
750 			result = crypto_invoke(crp, 0);
751 			if (result == ERESTART) {
752 				/*
753 				 * The driver ran out of resources, mark the
754 				 * driver ``blocked'' for cryptop's and put
755 				 * the op on the queue.
756 				 */
757 				mutex_spin_enter(&crypto_q_mtx);
758 				crypto_drivers[hid].cc_qblocked = 1;
759 				TAILQ_INSERT_HEAD(&crp_q, crp, crp_next);
760 				cryptostats.cs_blocks++;
761 				mutex_spin_exit(&crypto_q_mtx);
762 			}
763 			goto out_released;
764 		} else {
765 			/*
766 			 * The driver is blocked, just queue the op until
767 			 * it unblocks and the swi thread gets kicked.
768 			 */
769 			TAILQ_INSERT_TAIL(&crp_q, crp, crp_next);
770 			result = 0;
771 		}
772 	} else {
773 		int wasempty = TAILQ_EMPTY(&crp_q);
774 		/*
775 		 * Caller marked the request as ``ok to delay'';
776 		 * queue it for the swi thread.  This is desirable
777 		 * when the operation is low priority and/or suitable
778 		 * for batching.
779 		 */
780 		TAILQ_INSERT_TAIL(&crp_q, crp, crp_next);
781 		if (wasempty) {
782 			setsoftcrypto(softintr_cookie);
783 			mutex_spin_exit(&crypto_q_mtx);
784 			result = 0;
785 			goto out_released;
786 		}
787 
788 		result = 0;
789 	}
790 
791 	mutex_spin_exit(&crypto_q_mtx);
792 out_released:
793 	return result;
794 }
795 
796 /*
797  * Add an asymetric crypto request to a queue,
798  * to be processed by the kernel thread.
799  */
800 int
801 crypto_kdispatch(struct cryptkop *krp)
802 {
803 	struct cryptocap *cap;
804 	int result;
805 
806 	mutex_spin_enter(&crypto_q_mtx);
807 	cryptostats.cs_kops++;
808 
809 	cap = crypto_checkdriver(krp->krp_hid);
810 	if (cap && !cap->cc_kqblocked) {
811 		mutex_spin_exit(&crypto_q_mtx);
812 		result = crypto_kinvoke(krp, 0);
813 		if (result == ERESTART) {
814 			/*
815 			 * The driver ran out of resources, mark the
816 			 * driver ``blocked'' for cryptop's and put
817 			 * the op on the queue.
818 			 */
819 			mutex_spin_enter(&crypto_q_mtx);
820 			crypto_drivers[krp->krp_hid].cc_kqblocked = 1;
821 			TAILQ_INSERT_HEAD(&crp_kq, krp, krp_next);
822 			cryptostats.cs_kblocks++;
823 			mutex_spin_exit(&crypto_q_mtx);
824 		}
825 	} else {
826 		/*
827 		 * The driver is blocked, just queue the op until
828 		 * it unblocks and the swi thread gets kicked.
829 		 */
830 		TAILQ_INSERT_TAIL(&crp_kq, krp, krp_next);
831 		result = 0;
832 		mutex_spin_exit(&crypto_q_mtx);
833 	}
834 
835 	return result;
836 }
837 
838 /*
839  * Dispatch an assymetric crypto request to the appropriate crypto devices.
840  */
841 static int
842 crypto_kinvoke(struct cryptkop *krp, int hint)
843 {
844 	u_int32_t hid;
845 	int error;
846 
847 	/* Sanity checks. */
848 	if (krp == NULL)
849 		return EINVAL;
850 	if (krp->krp_callback == NULL) {
851 		cv_destroy(&krp->krp_cv);
852 		pool_put(&cryptkop_pool, krp);
853 		return EINVAL;
854 	}
855 
856 	mutex_enter(&crypto_mtx);
857 	for (hid = 0; hid < crypto_drivers_num; hid++) {
858 		if ((crypto_drivers[hid].cc_flags & CRYPTOCAP_F_SOFTWARE) &&
859 		    crypto_devallowsoft == 0)
860 			continue;
861 		if (crypto_drivers[hid].cc_kprocess == NULL)
862 			continue;
863 		if ((crypto_drivers[hid].cc_kalg[krp->krp_op] &
864 		    CRYPTO_ALG_FLAG_SUPPORTED) == 0)
865 			continue;
866 		break;
867 	}
868 	if (hid < crypto_drivers_num) {
869 		int (*process)(void *, struct cryptkop *, int);
870 		void *arg;
871 
872 		process = crypto_drivers[hid].cc_kprocess;
873 		arg = crypto_drivers[hid].cc_karg;
874 		mutex_exit(&crypto_mtx);
875 		krp->krp_hid = hid;
876 		error = (*process)(arg, krp, hint);
877 	} else {
878 		mutex_exit(&crypto_mtx);
879 		error = ENODEV;
880 	}
881 
882 	if (error) {
883 		krp->krp_status = error;
884 		crypto_kdone(krp);
885 	}
886 	return 0;
887 }
888 
889 #ifdef CRYPTO_TIMING
890 static void
891 crypto_tstat(struct cryptotstat *ts, struct timespec *tv)
892 {
893 	struct timespec now, t;
894 
895 	nanouptime(&now);
896 	t.tv_sec = now.tv_sec - tv->tv_sec;
897 	t.tv_nsec = now.tv_nsec - tv->tv_nsec;
898 	if (t.tv_nsec < 0) {
899 		t.tv_sec--;
900 		t.tv_nsec += 1000000000;
901 	}
902 	timespecadd(&ts->acc, &t, &t);
903 	if (timespeccmp(&t, &ts->min, <))
904 		ts->min = t;
905 	if (timespeccmp(&t, &ts->max, >))
906 		ts->max = t;
907 	ts->count++;
908 
909 	*tv = now;
910 }
911 #endif
912 
913 /*
914  * Dispatch a crypto request to the appropriate crypto devices.
915  */
916 static int
917 crypto_invoke(struct cryptop *crp, int hint)
918 {
919 	u_int32_t hid;
920 
921 #ifdef CRYPTO_TIMING
922 	if (crypto_timing)
923 		crypto_tstat(&cryptostats.cs_invoke, &crp->crp_tstamp);
924 #endif
925 	/* Sanity checks. */
926 	if (crp == NULL)
927 		return EINVAL;
928 	if (crp->crp_callback == NULL) {
929 		return EINVAL;
930 	}
931 	if (crp->crp_desc == NULL) {
932 		crp->crp_etype = EINVAL;
933 		crypto_done(crp);
934 		return 0;
935 	}
936 
937 	hid = CRYPTO_SESID2HID(crp->crp_sid);
938 
939 	if (hid < crypto_drivers_num) {
940 		int (*process)(void *, struct cryptop *, int);
941 		void *arg;
942 
943 		if (crypto_drivers[hid].cc_flags & CRYPTOCAP_F_CLEANUP) {
944 			mutex_exit(&crypto_mtx);
945 			crypto_freesession(crp->crp_sid);
946 			mutex_enter(&crypto_mtx);
947 		}
948 		process = crypto_drivers[hid].cc_process;
949 		arg = crypto_drivers[hid].cc_arg;
950 
951 		/*
952 		 * Invoke the driver to process the request.
953 		 */
954 		DPRINTF(("calling process for %p\n", crp));
955 		return (*process)(arg, crp, hint);
956 	} else {
957 		struct cryptodesc *crd;
958 		u_int64_t nid = 0;
959 
960 		/*
961 		 * Driver has unregistered; migrate the session and return
962 		 * an error to the caller so they'll resubmit the op.
963 		 */
964 		for (crd = crp->crp_desc; crd->crd_next; crd = crd->crd_next)
965 			crd->CRD_INI.cri_next = &(crd->crd_next->CRD_INI);
966 
967 		if (crypto_newsession(&nid, &(crp->crp_desc->CRD_INI), 0) == 0)
968 			crp->crp_sid = nid;
969 
970 		crp->crp_etype = EAGAIN;
971 
972 		crypto_done(crp);
973 		return 0;
974 	}
975 }
976 
977 /*
978  * Release a set of crypto descriptors.
979  */
980 void
981 crypto_freereq(struct cryptop *crp)
982 {
983 	struct cryptodesc *crd;
984 
985 	if (crp == NULL)
986 		return;
987 	DPRINTF(("crypto_freereq[%u]: crp %p\n",
988 		CRYPTO_SESID2LID(crp->crp_sid), crp));
989 
990 	/* sanity check */
991 	if (crp->crp_flags & CRYPTO_F_ONRETQ) {
992 		panic("crypto_freereq() freeing crp on RETQ\n");
993 	}
994 
995 	while ((crd = crp->crp_desc) != NULL) {
996 		crp->crp_desc = crd->crd_next;
997 		pool_put(&cryptodesc_pool, crd);
998 	}
999 	pool_put(&cryptop_pool, crp);
1000 }
1001 
1002 /*
1003  * Acquire a set of crypto descriptors.
1004  */
1005 struct cryptop *
1006 crypto_getreq(int num)
1007 {
1008 	struct cryptodesc *crd;
1009 	struct cryptop *crp;
1010 
1011 	crp = pool_get(&cryptop_pool, 0);
1012 	if (crp == NULL) {
1013 		return NULL;
1014 	}
1015 	memset(crp, 0, sizeof(struct cryptop));
1016 
1017 	while (num--) {
1018 		crd = pool_get(&cryptodesc_pool, 0);
1019 		if (crd == NULL) {
1020 			crypto_freereq(crp);
1021 			return NULL;
1022 		}
1023 
1024 		memset(crd, 0, sizeof(struct cryptodesc));
1025 		crd->crd_next = crp->crp_desc;
1026 		crp->crp_desc = crd;
1027 	}
1028 
1029 	return crp;
1030 }
1031 
1032 /*
1033  * Invoke the callback on behalf of the driver.
1034  */
1035 void
1036 crypto_done(struct cryptop *crp)
1037 {
1038 	int wasempty;
1039 
1040 	if (crp->crp_etype != 0)
1041 		cryptostats.cs_errs++;
1042 #ifdef CRYPTO_TIMING
1043 	if (crypto_timing)
1044 		crypto_tstat(&cryptostats.cs_done, &crp->crp_tstamp);
1045 #endif
1046 	DPRINTF(("crypto_done[%u]: crp %p\n",
1047 		CRYPTO_SESID2LID(crp->crp_sid), crp));
1048 
1049 	/*
1050 	 * Normal case; queue the callback for the thread.
1051 	 *
1052 	 * The return queue is manipulated by the swi thread
1053 	 * and, potentially, by crypto device drivers calling
1054 	 * back to mark operations completed.  Thus we need
1055 	 * to mask both while manipulating the return queue.
1056 	 */
1057   	if (crp->crp_flags & CRYPTO_F_CBIMM) {
1058 		/*
1059 	 	* Do the callback directly.  This is ok when the
1060   	 	* callback routine does very little (e.g. the
1061 	 	* /dev/crypto callback method just does a wakeup).
1062 	 	*/
1063 		mutex_spin_enter(&crypto_ret_q_mtx);
1064 		crp->crp_flags |= CRYPTO_F_DONE;
1065 		mutex_spin_exit(&crypto_ret_q_mtx);
1066 
1067 #ifdef CRYPTO_TIMING
1068 		if (crypto_timing) {
1069 			/*
1070 		 	* NB: We must copy the timestamp before
1071 		 	* doing the callback as the cryptop is
1072 		 	* likely to be reclaimed.
1073 		 	*/
1074 			struct timespec t = crp->crp_tstamp;
1075 			crypto_tstat(&cryptostats.cs_cb, &t);
1076 			crp->crp_callback(crp);
1077 			crypto_tstat(&cryptostats.cs_finis, &t);
1078 		} else
1079 #endif
1080 		crp->crp_callback(crp);
1081 	} else {
1082 		mutex_spin_enter(&crypto_ret_q_mtx);
1083 		crp->crp_flags |= CRYPTO_F_DONE;
1084 
1085 		if (crp->crp_flags & CRYPTO_F_USER) {
1086 			/* the request has completed while
1087 			 * running in the user context
1088 			 * so don't queue it - the user
1089 			 * thread won't sleep when it sees
1090 			 * the CRYPTO_F_DONE flag.
1091 			 * This is an optimization to avoid
1092 			 * unecessary context switches.
1093 			 */
1094 			DPRINTF(("crypto_done[%u]: crp %p CRYPTO_F_USER\n",
1095 				CRYPTO_SESID2LID(crp->crp_sid), crp));
1096 		} else {
1097 			wasempty = TAILQ_EMPTY(&crp_ret_q);
1098 			DPRINTF(("crypto_done[%u]: queueing %p\n",
1099 				CRYPTO_SESID2LID(crp->crp_sid), crp));
1100 			crp->crp_flags |= CRYPTO_F_ONRETQ;
1101 			TAILQ_INSERT_TAIL(&crp_ret_q, crp, crp_next);
1102 			if (wasempty) {
1103 				DPRINTF(("crypto_done[%u]: waking cryptoret, "
1104 					"crp %p hit empty queue\n.",
1105 					CRYPTO_SESID2LID(crp->crp_sid), crp));
1106 				cv_signal(&cryptoret_cv);
1107 			}
1108 		}
1109 		mutex_spin_exit(&crypto_ret_q_mtx);
1110 	}
1111 }
1112 
1113 /*
1114  * Invoke the callback on behalf of the driver.
1115  */
1116 void
1117 crypto_kdone(struct cryptkop *krp)
1118 {
1119 	int wasempty;
1120 
1121 	if (krp->krp_status != 0)
1122 		cryptostats.cs_kerrs++;
1123 
1124 	krp->krp_flags |= CRYPTO_F_DONE;
1125 
1126 	/*
1127 	 * The return queue is manipulated by the swi thread
1128 	 * and, potentially, by crypto device drivers calling
1129 	 * back to mark operations completed.  Thus we need
1130 	 * to mask both while manipulating the return queue.
1131 	 */
1132 	if (krp->krp_flags & CRYPTO_F_CBIMM) {
1133 		krp->krp_callback(krp);
1134 	} else {
1135 		mutex_spin_enter(&crypto_ret_q_mtx);
1136 		wasempty = TAILQ_EMPTY(&crp_ret_kq);
1137 		krp->krp_flags |= CRYPTO_F_ONRETQ;
1138 		TAILQ_INSERT_TAIL(&crp_ret_kq, krp, krp_next);
1139 		if (wasempty)
1140 			cv_signal(&cryptoret_cv);
1141 		mutex_spin_exit(&crypto_ret_q_mtx);
1142 	}
1143 }
1144 
1145 int
1146 crypto_getfeat(int *featp)
1147 {
1148 	int hid, kalg, feat = 0;
1149 
1150 	mutex_enter(&crypto_mtx);
1151 
1152 	if (crypto_userasymcrypto == 0)
1153 		goto out;
1154 
1155 	for (hid = 0; hid < crypto_drivers_num; hid++) {
1156 		if ((crypto_drivers[hid].cc_flags & CRYPTOCAP_F_SOFTWARE) &&
1157 		    crypto_devallowsoft == 0) {
1158 			continue;
1159 		}
1160 		if (crypto_drivers[hid].cc_kprocess == NULL)
1161 			continue;
1162 		for (kalg = 0; kalg < CRK_ALGORITHM_MAX; kalg++)
1163 			if ((crypto_drivers[hid].cc_kalg[kalg] &
1164 			    CRYPTO_ALG_FLAG_SUPPORTED) != 0)
1165 				feat |=  1 << kalg;
1166 	}
1167 out:
1168 	mutex_exit(&crypto_mtx);
1169 	*featp = feat;
1170 	return (0);
1171 }
1172 
1173 /*
1174  * Software interrupt thread to dispatch crypto requests.
1175  */
1176 static void
1177 cryptointr(void)
1178 {
1179 	struct cryptop *crp, *submit, *cnext;
1180 	struct cryptkop *krp, *knext;
1181 	struct cryptocap *cap;
1182 	int result, hint;
1183 
1184 	cryptostats.cs_intrs++;
1185 	mutex_spin_enter(&crypto_q_mtx);
1186 	do {
1187 		/*
1188 		 * Find the first element in the queue that can be
1189 		 * processed and look-ahead to see if multiple ops
1190 		 * are ready for the same driver.
1191 		 */
1192 		submit = NULL;
1193 		hint = 0;
1194 		TAILQ_FOREACH_SAFE(crp, &crp_q, crp_next, cnext) {
1195 			u_int32_t hid = CRYPTO_SESID2HID(crp->crp_sid);
1196 			cap = crypto_checkdriver(hid);
1197 			if (cap == NULL || cap->cc_process == NULL) {
1198 				/* Op needs to be migrated, process it. */
1199 				if (submit == NULL)
1200 					submit = crp;
1201 				break;
1202 			}
1203 			if (!cap->cc_qblocked) {
1204 				if (submit != NULL) {
1205 					/*
1206 					 * We stop on finding another op,
1207 					 * regardless whether its for the same
1208 					 * driver or not.  We could keep
1209 					 * searching the queue but it might be
1210 					 * better to just use a per-driver
1211 					 * queue instead.
1212 					 */
1213 					if (CRYPTO_SESID2HID(submit->crp_sid)
1214 					    == hid)
1215 						hint = CRYPTO_HINT_MORE;
1216 					break;
1217 				} else {
1218 					submit = crp;
1219 					if ((submit->crp_flags & CRYPTO_F_BATCH) == 0)
1220 						break;
1221 					/* keep scanning for more are q'd */
1222 				}
1223 			}
1224 		}
1225 		if (submit != NULL) {
1226 			TAILQ_REMOVE(&crp_q, submit, crp_next);
1227 			mutex_spin_exit(&crypto_q_mtx);
1228 			result = crypto_invoke(submit, hint);
1229 			/* we must take here as the TAILQ op or kinvoke
1230 			   may need this mutex below.  sigh. */
1231 			mutex_spin_enter(&crypto_q_mtx);
1232 			if (result == ERESTART) {
1233 				/*
1234 				 * The driver ran out of resources, mark the
1235 				 * driver ``blocked'' for cryptop's and put
1236 				 * the request back in the queue.  It would
1237 				 * best to put the request back where we got
1238 				 * it but that's hard so for now we put it
1239 				 * at the front.  This should be ok; putting
1240 				 * it at the end does not work.
1241 				 */
1242 				/* XXX validate sid again? */
1243 				crypto_drivers[CRYPTO_SESID2HID(submit->crp_sid)].cc_qblocked = 1;
1244 				TAILQ_INSERT_HEAD(&crp_q, submit, crp_next);
1245 				cryptostats.cs_blocks++;
1246 			}
1247 		}
1248 
1249 		/* As above, but for key ops */
1250 		TAILQ_FOREACH_SAFE(krp, &crp_kq, krp_next, knext) {
1251 			cap = crypto_checkdriver(krp->krp_hid);
1252 			if (cap == NULL || cap->cc_kprocess == NULL) {
1253 				/* Op needs to be migrated, process it. */
1254 				break;
1255 			}
1256 			if (!cap->cc_kqblocked)
1257 				break;
1258 		}
1259 		if (krp != NULL) {
1260 			TAILQ_REMOVE(&crp_kq, krp, krp_next);
1261 			mutex_spin_exit(&crypto_q_mtx);
1262 			result = crypto_kinvoke(krp, 0);
1263 			/* the next iteration will want the mutex. :-/ */
1264 			mutex_spin_enter(&crypto_q_mtx);
1265 			if (result == ERESTART) {
1266 				/*
1267 				 * The driver ran out of resources, mark the
1268 				 * driver ``blocked'' for cryptkop's and put
1269 				 * the request back in the queue.  It would
1270 				 * best to put the request back where we got
1271 				 * it but that's hard so for now we put it
1272 				 * at the front.  This should be ok; putting
1273 				 * it at the end does not work.
1274 				 */
1275 				/* XXX validate sid again? */
1276 				crypto_drivers[krp->krp_hid].cc_kqblocked = 1;
1277 				TAILQ_INSERT_HEAD(&crp_kq, krp, krp_next);
1278 				cryptostats.cs_kblocks++;
1279 			}
1280 		}
1281 	} while (submit != NULL || krp != NULL);
1282 	mutex_spin_exit(&crypto_q_mtx);
1283 }
1284 
1285 /*
1286  * Kernel thread to do callbacks.
1287  */
1288 static void
1289 cryptoret(void)
1290 {
1291 	struct cryptop *crp;
1292 	struct cryptkop *krp;
1293 
1294 	mutex_spin_enter(&crypto_ret_q_mtx);
1295 	for (;;) {
1296 		crp = TAILQ_FIRST(&crp_ret_q);
1297 		if (crp != NULL) {
1298 			TAILQ_REMOVE(&crp_ret_q, crp, crp_next);
1299 			crp->crp_flags &= ~CRYPTO_F_ONRETQ;
1300 		}
1301 		krp = TAILQ_FIRST(&crp_ret_kq);
1302 		if (krp != NULL) {
1303 			TAILQ_REMOVE(&crp_ret_kq, krp, krp_next);
1304 			krp->krp_flags &= ~CRYPTO_F_ONRETQ;
1305 		}
1306 
1307 		/* drop before calling any callbacks. */
1308 		if (crp == NULL && krp == NULL) {
1309 			cryptostats.cs_rets++;
1310 			cv_wait(&cryptoret_cv, &crypto_ret_q_mtx);
1311 			continue;
1312 		}
1313 
1314 		mutex_spin_exit(&crypto_ret_q_mtx);
1315 
1316 		if (crp != NULL) {
1317 #ifdef CRYPTO_TIMING
1318 			if (crypto_timing) {
1319 				/*
1320 				 * NB: We must copy the timestamp before
1321 				 * doing the callback as the cryptop is
1322 				 * likely to be reclaimed.
1323 				 */
1324 				struct timespec t = crp->crp_tstamp;
1325 				crypto_tstat(&cryptostats.cs_cb, &t);
1326 				crp->crp_callback(crp);
1327 				crypto_tstat(&cryptostats.cs_finis, &t);
1328 			} else
1329 #endif
1330 			{
1331 				crp->crp_callback(crp);
1332 			}
1333 		}
1334 		if (krp != NULL)
1335 			krp->krp_callback(krp);
1336 
1337 		mutex_spin_enter(&crypto_ret_q_mtx);
1338 	}
1339 }
1340 
1341 /* NetBSD module interface */
1342 
1343 MODULE(MODULE_CLASS_MISC, opencrypto, NULL);
1344 
1345 static int
1346 opencrypto_modcmd(modcmd_t cmd, void *opaque)
1347 {
1348 
1349 	switch (cmd) {
1350 	case MODULE_CMD_INIT:
1351 #ifdef _MODULE
1352 		crypto_init();
1353 #endif
1354 		return 0;
1355 	case MODULE_CMD_FINI:
1356 #ifdef _MODULE
1357 		sysctl_teardown(&sysctl_opencrypto_clog);
1358 #endif
1359 		return 0;
1360 	default:
1361 		return ENOTTY;
1362 	}
1363 }
1364