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crypto.c revision 1.40
      1 /*	$NetBSD: crypto.c,v 1.40 2011/05/16 10:27:49 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 (at) 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 1.40 2011/05/16 10:27:49 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, reqid 0x%x, alg %d\n",
    724 		crp, crp->crp_reqid, 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 	mutex_enter(&crypto_mtx);
    932 	if (hid < crypto_drivers_num) {
    933 		int (*process)(void *, struct cryptop *, int);
    934 		void *arg;
    935 
    936 		if (crypto_drivers[hid].cc_flags & CRYPTOCAP_F_CLEANUP) {
    937 			mutex_exit(&crypto_mtx);
    938 			crypto_freesession(crp->crp_sid);
    939 			mutex_enter(&crypto_mtx);
    940 		}
    941 		process = crypto_drivers[hid].cc_process;
    942 		arg = crypto_drivers[hid].cc_arg;
    943 		mutex_exit(&crypto_mtx);
    944 
    945 		/*
    946 		 * Invoke the driver to process the request.
    947 		 */
    948 		DPRINTF(("calling process for %p\n", crp));
    949 		return (*process)(arg, crp, hint);
    950 	} else {
    951 		struct cryptodesc *crd;
    952 		u_int64_t nid = 0;
    953 
    954 		/*
    955 		 * Driver has unregistered; migrate the session and return
    956 		 * an error to the caller so they'll resubmit the op.
    957 		 */
    958 		for (crd = crp->crp_desc; crd->crd_next; crd = crd->crd_next)
    959 			crd->CRD_INI.cri_next = &(crd->crd_next->CRD_INI);
    960 
    961 		mutex_exit(&crypto_mtx);
    962 
    963 		if (crypto_newsession(&nid, &(crp->crp_desc->CRD_INI), 0) == 0)
    964 			crp->crp_sid = nid;
    965 
    966 		crp->crp_etype = EAGAIN;
    967 
    968 		crypto_done(crp);
    969 		return 0;
    970 	}
    971 }
    972 
    973 /*
    974  * Release a set of crypto descriptors.
    975  */
    976 void
    977 crypto_freereq(struct cryptop *crp)
    978 {
    979 	struct cryptodesc *crd;
    980 
    981 	if (crp == NULL)
    982 		return;
    983 	DPRINTF(("crypto_freereq[%u]: crp %p\n",
    984 		CRYPTO_SESID2LID(crp->crp_sid), crp));
    985 
    986 	/* sanity check */
    987 	if (crp->crp_flags & CRYPTO_F_ONRETQ) {
    988 		panic("crypto_freereq() freeing crp on RETQ\n");
    989 	}
    990 
    991 	while ((crd = crp->crp_desc) != NULL) {
    992 		crp->crp_desc = crd->crd_next;
    993 		pool_put(&cryptodesc_pool, crd);
    994 	}
    995 	cv_destroy(&crp->crp_cv);
    996 	pool_put(&cryptop_pool, crp);
    997 }
    998 
    999 /*
   1000  * Acquire a set of crypto descriptors.
   1001  */
   1002 struct cryptop *
   1003 crypto_getreq(int num)
   1004 {
   1005 	struct cryptodesc *crd;
   1006 	struct cryptop *crp;
   1007 
   1008 	crp = pool_get(&cryptop_pool, 0);
   1009 	if (crp == NULL) {
   1010 		return NULL;
   1011 	}
   1012 	memset(crp, 0, sizeof(struct cryptop));
   1013 	cv_init(&crp->crp_cv, "crydev");
   1014 
   1015 	while (num--) {
   1016 		crd = pool_get(&cryptodesc_pool, 0);
   1017 		if (crd == NULL) {
   1018 			crypto_freereq(crp);
   1019 			return NULL;
   1020 		}
   1021 
   1022 		memset(crd, 0, sizeof(struct cryptodesc));
   1023 		crd->crd_next = crp->crp_desc;
   1024 		crp->crp_desc = crd;
   1025 	}
   1026 
   1027 	return crp;
   1028 }
   1029 
   1030 /*
   1031  * Invoke the callback on behalf of the driver.
   1032  */
   1033 void
   1034 crypto_done(struct cryptop *crp)
   1035 {
   1036 	int wasempty;
   1037 
   1038 	if (crp->crp_etype != 0)
   1039 		cryptostats.cs_errs++;
   1040 #ifdef CRYPTO_TIMING
   1041 	if (crypto_timing)
   1042 		crypto_tstat(&cryptostats.cs_done, &crp->crp_tstamp);
   1043 #endif
   1044 	DPRINTF(("crypto_done[%u]: crp %p\n",
   1045 		CRYPTO_SESID2LID(crp->crp_sid), crp));
   1046 
   1047 	/*
   1048 	 * Normal case; queue the callback for the thread.
   1049 	 *
   1050 	 * The return queue is manipulated by the swi thread
   1051 	 * and, potentially, by crypto device drivers calling
   1052 	 * back to mark operations completed.  Thus we need
   1053 	 * to mask both while manipulating the return queue.
   1054 	 */
   1055   	if (crp->crp_flags & CRYPTO_F_CBIMM) {
   1056 		/*
   1057 	 	* Do the callback directly.  This is ok when the
   1058   	 	* callback routine does very little (e.g. the
   1059 	 	* /dev/crypto callback method just does a wakeup).
   1060 	 	*/
   1061 		mutex_spin_enter(&crypto_ret_q_mtx);
   1062 		crp->crp_flags |= CRYPTO_F_DONE;
   1063 		mutex_spin_exit(&crypto_ret_q_mtx);
   1064 
   1065 #ifdef CRYPTO_TIMING
   1066 		if (crypto_timing) {
   1067 			/*
   1068 		 	* NB: We must copy the timestamp before
   1069 		 	* doing the callback as the cryptop is
   1070 		 	* likely to be reclaimed.
   1071 		 	*/
   1072 			struct timespec t = crp->crp_tstamp;
   1073 			crypto_tstat(&cryptostats.cs_cb, &t);
   1074 			crp->crp_callback(crp);
   1075 			crypto_tstat(&cryptostats.cs_finis, &t);
   1076 		} else
   1077 #endif
   1078 		crp->crp_callback(crp);
   1079 	} else {
   1080 		mutex_spin_enter(&crypto_ret_q_mtx);
   1081 		crp->crp_flags |= CRYPTO_F_DONE;
   1082 
   1083 		if (crp->crp_flags & CRYPTO_F_USER) {
   1084 			/* the request has completed while
   1085 			 * running in the user context
   1086 			 * so don't queue it - the user
   1087 			 * thread won't sleep when it sees
   1088 			 * the CRYPTO_F_DONE flag.
   1089 			 * This is an optimization to avoid
   1090 			 * unecessary context switches.
   1091 			 */
   1092 			DPRINTF(("crypto_done[%u]: crp %p CRYPTO_F_USER\n",
   1093 				CRYPTO_SESID2LID(crp->crp_sid), crp));
   1094 		} else {
   1095 			wasempty = TAILQ_EMPTY(&crp_ret_q);
   1096 			DPRINTF(("crypto_done[%u]: queueing %p\n",
   1097 				CRYPTO_SESID2LID(crp->crp_sid), crp));
   1098 			crp->crp_flags |= CRYPTO_F_ONRETQ;
   1099 			TAILQ_INSERT_TAIL(&crp_ret_q, crp, crp_next);
   1100 			if (wasempty) {
   1101 				DPRINTF(("crypto_done[%u]: waking cryptoret, "
   1102 					"crp %p hit empty queue\n.",
   1103 					CRYPTO_SESID2LID(crp->crp_sid), crp));
   1104 				cv_signal(&cryptoret_cv);
   1105 			}
   1106 		}
   1107 		mutex_spin_exit(&crypto_ret_q_mtx);
   1108 	}
   1109 }
   1110 
   1111 /*
   1112  * Invoke the callback on behalf of the driver.
   1113  */
   1114 void
   1115 crypto_kdone(struct cryptkop *krp)
   1116 {
   1117 	int wasempty;
   1118 
   1119 	if (krp->krp_status != 0)
   1120 		cryptostats.cs_kerrs++;
   1121 
   1122 	krp->krp_flags |= CRYPTO_F_DONE;
   1123 
   1124 	/*
   1125 	 * The return queue is manipulated by the swi thread
   1126 	 * and, potentially, by crypto device drivers calling
   1127 	 * back to mark operations completed.  Thus we need
   1128 	 * to mask both while manipulating the return queue.
   1129 	 */
   1130 	if (krp->krp_flags & CRYPTO_F_CBIMM) {
   1131 		krp->krp_callback(krp);
   1132 	} else {
   1133 		mutex_spin_enter(&crypto_ret_q_mtx);
   1134 		wasempty = TAILQ_EMPTY(&crp_ret_kq);
   1135 		krp->krp_flags |= CRYPTO_F_ONRETQ;
   1136 		TAILQ_INSERT_TAIL(&crp_ret_kq, krp, krp_next);
   1137 		if (wasempty)
   1138 			cv_signal(&cryptoret_cv);
   1139 		mutex_spin_exit(&crypto_ret_q_mtx);
   1140 	}
   1141 }
   1142 
   1143 int
   1144 crypto_getfeat(int *featp)
   1145 {
   1146 	int hid, kalg, feat = 0;
   1147 
   1148 	mutex_enter(&crypto_mtx);
   1149 
   1150 	if (crypto_userasymcrypto == 0)
   1151 		goto out;
   1152 
   1153 	for (hid = 0; hid < crypto_drivers_num; hid++) {
   1154 		if ((crypto_drivers[hid].cc_flags & CRYPTOCAP_F_SOFTWARE) &&
   1155 		    crypto_devallowsoft == 0) {
   1156 			continue;
   1157 		}
   1158 		if (crypto_drivers[hid].cc_kprocess == NULL)
   1159 			continue;
   1160 		for (kalg = 0; kalg < CRK_ALGORITHM_MAX; kalg++)
   1161 			if ((crypto_drivers[hid].cc_kalg[kalg] &
   1162 			    CRYPTO_ALG_FLAG_SUPPORTED) != 0)
   1163 				feat |=  1 << kalg;
   1164 	}
   1165 out:
   1166 	mutex_exit(&crypto_mtx);
   1167 	*featp = feat;
   1168 	return (0);
   1169 }
   1170 
   1171 /*
   1172  * Software interrupt thread to dispatch crypto requests.
   1173  */
   1174 static void
   1175 cryptointr(void)
   1176 {
   1177 	struct cryptop *crp, *submit, *cnext;
   1178 	struct cryptkop *krp, *knext;
   1179 	struct cryptocap *cap;
   1180 	int result, hint;
   1181 
   1182 	cryptostats.cs_intrs++;
   1183 	mutex_spin_enter(&crypto_q_mtx);
   1184 	do {
   1185 		/*
   1186 		 * Find the first element in the queue that can be
   1187 		 * processed and look-ahead to see if multiple ops
   1188 		 * are ready for the same driver.
   1189 		 */
   1190 		submit = NULL;
   1191 		hint = 0;
   1192 		TAILQ_FOREACH_SAFE(crp, &crp_q, crp_next, cnext) {
   1193 			u_int32_t hid = CRYPTO_SESID2HID(crp->crp_sid);
   1194 			cap = crypto_checkdriver(hid);
   1195 			if (cap == NULL || cap->cc_process == NULL) {
   1196 				/* Op needs to be migrated, process it. */
   1197 				if (submit == NULL)
   1198 					submit = crp;
   1199 				break;
   1200 			}
   1201 			if (!cap->cc_qblocked) {
   1202 				if (submit != NULL) {
   1203 					/*
   1204 					 * We stop on finding another op,
   1205 					 * regardless whether its for the same
   1206 					 * driver or not.  We could keep
   1207 					 * searching the queue but it might be
   1208 					 * better to just use a per-driver
   1209 					 * queue instead.
   1210 					 */
   1211 					if (CRYPTO_SESID2HID(submit->crp_sid)
   1212 					    == hid)
   1213 						hint = CRYPTO_HINT_MORE;
   1214 					break;
   1215 				} else {
   1216 					submit = crp;
   1217 					if ((submit->crp_flags & CRYPTO_F_BATCH) == 0)
   1218 						break;
   1219 					/* keep scanning for more are q'd */
   1220 				}
   1221 			}
   1222 		}
   1223 		if (submit != NULL) {
   1224 			TAILQ_REMOVE(&crp_q, submit, crp_next);
   1225 			mutex_spin_exit(&crypto_q_mtx);
   1226 			result = crypto_invoke(submit, hint);
   1227 			/* we must take here as the TAILQ op or kinvoke
   1228 			   may need this mutex below.  sigh. */
   1229 			mutex_spin_enter(&crypto_q_mtx);
   1230 			if (result == ERESTART) {
   1231 				/*
   1232 				 * The driver ran out of resources, mark the
   1233 				 * driver ``blocked'' for cryptop's and put
   1234 				 * the request back in the queue.  It would
   1235 				 * best to put the request back where we got
   1236 				 * it but that's hard so for now we put it
   1237 				 * at the front.  This should be ok; putting
   1238 				 * it at the end does not work.
   1239 				 */
   1240 				/* XXX validate sid again? */
   1241 				crypto_drivers[CRYPTO_SESID2HID(submit->crp_sid)].cc_qblocked = 1;
   1242 				TAILQ_INSERT_HEAD(&crp_q, submit, crp_next);
   1243 				cryptostats.cs_blocks++;
   1244 			}
   1245 		}
   1246 
   1247 		/* As above, but for key ops */
   1248 		TAILQ_FOREACH_SAFE(krp, &crp_kq, krp_next, knext) {
   1249 			cap = crypto_checkdriver(krp->krp_hid);
   1250 			if (cap == NULL || cap->cc_kprocess == NULL) {
   1251 				/* Op needs to be migrated, process it. */
   1252 				break;
   1253 			}
   1254 			if (!cap->cc_kqblocked)
   1255 				break;
   1256 		}
   1257 		if (krp != NULL) {
   1258 			TAILQ_REMOVE(&crp_kq, krp, krp_next);
   1259 			mutex_spin_exit(&crypto_q_mtx);
   1260 			result = crypto_kinvoke(krp, 0);
   1261 			/* the next iteration will want the mutex. :-/ */
   1262 			mutex_spin_enter(&crypto_q_mtx);
   1263 			if (result == ERESTART) {
   1264 				/*
   1265 				 * The driver ran out of resources, mark the
   1266 				 * driver ``blocked'' for cryptkop's and put
   1267 				 * the request back in the queue.  It would
   1268 				 * best to put the request back where we got
   1269 				 * it but that's hard so for now we put it
   1270 				 * at the front.  This should be ok; putting
   1271 				 * it at the end does not work.
   1272 				 */
   1273 				/* XXX validate sid again? */
   1274 				crypto_drivers[krp->krp_hid].cc_kqblocked = 1;
   1275 				TAILQ_INSERT_HEAD(&crp_kq, krp, krp_next);
   1276 				cryptostats.cs_kblocks++;
   1277 			}
   1278 		}
   1279 	} while (submit != NULL || krp != NULL);
   1280 	mutex_spin_exit(&crypto_q_mtx);
   1281 }
   1282 
   1283 /*
   1284  * Kernel thread to do callbacks.
   1285  */
   1286 static void
   1287 cryptoret(void)
   1288 {
   1289 	struct cryptop *crp;
   1290 	struct cryptkop *krp;
   1291 
   1292 	mutex_spin_enter(&crypto_ret_q_mtx);
   1293 	for (;;) {
   1294 		crp = TAILQ_FIRST(&crp_ret_q);
   1295 		if (crp != NULL) {
   1296 			TAILQ_REMOVE(&crp_ret_q, crp, crp_next);
   1297 			crp->crp_flags &= ~CRYPTO_F_ONRETQ;
   1298 		}
   1299 		krp = TAILQ_FIRST(&crp_ret_kq);
   1300 		if (krp != NULL) {
   1301 			TAILQ_REMOVE(&crp_ret_kq, krp, krp_next);
   1302 			krp->krp_flags &= ~CRYPTO_F_ONRETQ;
   1303 		}
   1304 
   1305 		/* drop before calling any callbacks. */
   1306 		if (crp == NULL && krp == NULL) {
   1307 			cryptostats.cs_rets++;
   1308 			cv_wait(&cryptoret_cv, &crypto_ret_q_mtx);
   1309 			continue;
   1310 		}
   1311 
   1312 		mutex_spin_exit(&crypto_ret_q_mtx);
   1313 
   1314 		if (crp != NULL) {
   1315 #ifdef CRYPTO_TIMING
   1316 			if (crypto_timing) {
   1317 				/*
   1318 				 * NB: We must copy the timestamp before
   1319 				 * doing the callback as the cryptop is
   1320 				 * likely to be reclaimed.
   1321 				 */
   1322 				struct timespec t = crp->crp_tstamp;
   1323 				crypto_tstat(&cryptostats.cs_cb, &t);
   1324 				crp->crp_callback(crp);
   1325 				crypto_tstat(&cryptostats.cs_finis, &t);
   1326 			} else
   1327 #endif
   1328 			{
   1329 				crp->crp_callback(crp);
   1330 			}
   1331 		}
   1332 		if (krp != NULL)
   1333 			krp->krp_callback(krp);
   1334 
   1335 		mutex_spin_enter(&crypto_ret_q_mtx);
   1336 	}
   1337 }
   1338