xref: /freebsd/sys/opencrypto/crypto.c (revision fcb560670601b2a4d87bb31d7531c8dcc37ee71b)
1 /*-
2  * Copyright (c) 2002-2006 Sam Leffler.  All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
14  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
15  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
16  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
17  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
18  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
19  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
20  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
21  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
22  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23  */
24 
25 #include <sys/cdefs.h>
26 __FBSDID("$FreeBSD$");
27 
28 /*
29  * Cryptographic Subsystem.
30  *
31  * This code is derived from the Openbsd Cryptographic Framework (OCF)
32  * that has the copyright shown below.  Very little of the original
33  * code remains.
34  */
35 
36 /*-
37  * The author of this code is Angelos D. Keromytis (angelos@cis.upenn.edu)
38  *
39  * This code was written by Angelos D. Keromytis in Athens, Greece, in
40  * February 2000. Network Security Technologies Inc. (NSTI) kindly
41  * supported the development of this code.
42  *
43  * Copyright (c) 2000, 2001 Angelos D. Keromytis
44  *
45  * Permission to use, copy, and modify this software with or without fee
46  * is hereby granted, provided that this entire notice is included in
47  * all source code copies of any software which is or includes a copy or
48  * modification of this software.
49  *
50  * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
51  * IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
52  * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
53  * MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
54  * PURPOSE.
55  */
56 
57 #define	CRYPTO_TIMING				/* enable timing support */
58 
59 #include "opt_ddb.h"
60 
61 #include <sys/param.h>
62 #include <sys/systm.h>
63 #include <sys/eventhandler.h>
64 #include <sys/kernel.h>
65 #include <sys/kthread.h>
66 #include <sys/lock.h>
67 #include <sys/module.h>
68 #include <sys/mutex.h>
69 #include <sys/malloc.h>
70 #include <sys/proc.h>
71 #include <sys/sdt.h>
72 #include <sys/sysctl.h>
73 
74 #include <ddb/ddb.h>
75 
76 #include <vm/uma.h>
77 #include <opencrypto/cryptodev.h>
78 #include <opencrypto/xform.h>			/* XXX for M_XDATA */
79 
80 #include <sys/kobj.h>
81 #include <sys/bus.h>
82 #include "cryptodev_if.h"
83 
84 #if defined(__i386__) || defined(__amd64__)
85 #include <machine/pcb.h>
86 #endif
87 
88 SDT_PROVIDER_DEFINE(opencrypto);
89 
90 /*
91  * Crypto drivers register themselves by allocating a slot in the
92  * crypto_drivers table with crypto_get_driverid() and then registering
93  * each algorithm they support with crypto_register() and crypto_kregister().
94  */
95 static	struct mtx crypto_drivers_mtx;		/* lock on driver table */
96 #define	CRYPTO_DRIVER_LOCK()	mtx_lock(&crypto_drivers_mtx)
97 #define	CRYPTO_DRIVER_UNLOCK()	mtx_unlock(&crypto_drivers_mtx)
98 #define	CRYPTO_DRIVER_ASSERT()	mtx_assert(&crypto_drivers_mtx, MA_OWNED)
99 
100 /*
101  * Crypto device/driver capabilities structure.
102  *
103  * Synchronization:
104  * (d) - protected by CRYPTO_DRIVER_LOCK()
105  * (q) - protected by CRYPTO_Q_LOCK()
106  * Not tagged fields are read-only.
107  */
108 struct cryptocap {
109 	device_t	cc_dev;			/* (d) device/driver */
110 	u_int32_t	cc_sessions;		/* (d) # of sessions */
111 	u_int32_t	cc_koperations;		/* (d) # os asym operations */
112 	/*
113 	 * Largest possible operator length (in bits) for each type of
114 	 * encryption algorithm. XXX not used
115 	 */
116 	u_int16_t	cc_max_op_len[CRYPTO_ALGORITHM_MAX + 1];
117 	u_int8_t	cc_alg[CRYPTO_ALGORITHM_MAX + 1];
118 	u_int8_t	cc_kalg[CRK_ALGORITHM_MAX + 1];
119 
120 	int		cc_flags;		/* (d) flags */
121 #define CRYPTOCAP_F_CLEANUP	0x80000000	/* needs resource cleanup */
122 	int		cc_qblocked;		/* (q) symmetric q blocked */
123 	int		cc_kqblocked;		/* (q) asymmetric q blocked */
124 };
125 static	struct cryptocap *crypto_drivers = NULL;
126 static	int crypto_drivers_num = 0;
127 
128 /*
129  * There are two queues for crypto requests; one for symmetric (e.g.
130  * cipher) operations and one for asymmetric (e.g. MOD)operations.
131  * A single mutex is used to lock access to both queues.  We could
132  * have one per-queue but having one simplifies handling of block/unblock
133  * operations.
134  */
135 static	int crp_sleep = 0;
136 static	TAILQ_HEAD(,cryptop) crp_q;		/* request queues */
137 static	TAILQ_HEAD(,cryptkop) crp_kq;
138 static	struct mtx crypto_q_mtx;
139 #define	CRYPTO_Q_LOCK()		mtx_lock(&crypto_q_mtx)
140 #define	CRYPTO_Q_UNLOCK()	mtx_unlock(&crypto_q_mtx)
141 
142 /*
143  * There are two queues for processing completed crypto requests; one
144  * for the symmetric and one for the asymmetric ops.  We only need one
145  * but have two to avoid type futzing (cryptop vs. cryptkop).  A single
146  * mutex is used to lock access to both queues.  Note that this lock
147  * must be separate from the lock on request queues to insure driver
148  * callbacks don't generate lock order reversals.
149  */
150 static	TAILQ_HEAD(,cryptop) crp_ret_q;		/* callback queues */
151 static	TAILQ_HEAD(,cryptkop) crp_ret_kq;
152 static	struct mtx crypto_ret_q_mtx;
153 #define	CRYPTO_RETQ_LOCK()	mtx_lock(&crypto_ret_q_mtx)
154 #define	CRYPTO_RETQ_UNLOCK()	mtx_unlock(&crypto_ret_q_mtx)
155 #define	CRYPTO_RETQ_EMPTY()	(TAILQ_EMPTY(&crp_ret_q) && TAILQ_EMPTY(&crp_ret_kq))
156 
157 static	uma_zone_t cryptop_zone;
158 static	uma_zone_t cryptodesc_zone;
159 
160 int	crypto_userasymcrypto = 1;	/* userland may do asym crypto reqs */
161 SYSCTL_INT(_kern, OID_AUTO, userasymcrypto, CTLFLAG_RW,
162 	   &crypto_userasymcrypto, 0,
163 	   "Enable/disable user-mode access to asymmetric crypto support");
164 int	crypto_devallowsoft = 0;	/* only use hardware crypto */
165 SYSCTL_INT(_kern, OID_AUTO, cryptodevallowsoft, CTLFLAG_RW,
166 	   &crypto_devallowsoft, 0,
167 	   "Enable/disable use of software crypto by /dev/crypto");
168 
169 MALLOC_DEFINE(M_CRYPTO_DATA, "crypto", "crypto session records");
170 
171 static	void crypto_proc(void);
172 static	struct proc *cryptoproc;
173 static	void crypto_ret_proc(void);
174 static	struct proc *cryptoretproc;
175 static	void crypto_destroy(void);
176 static	int crypto_invoke(struct cryptocap *cap, struct cryptop *crp, int hint);
177 static	int crypto_kinvoke(struct cryptkop *krp, int flags);
178 
179 static	struct cryptostats cryptostats;
180 SYSCTL_STRUCT(_kern, OID_AUTO, crypto_stats, CTLFLAG_RW, &cryptostats,
181 	    cryptostats, "Crypto system statistics");
182 
183 #ifdef CRYPTO_TIMING
184 static	int crypto_timing = 0;
185 SYSCTL_INT(_debug, OID_AUTO, crypto_timing, CTLFLAG_RW,
186 	   &crypto_timing, 0, "Enable/disable crypto timing support");
187 #endif
188 
189 static int
190 crypto_init(void)
191 {
192 	int error;
193 
194 	mtx_init(&crypto_drivers_mtx, "crypto", "crypto driver table",
195 		MTX_DEF|MTX_QUIET);
196 
197 	TAILQ_INIT(&crp_q);
198 	TAILQ_INIT(&crp_kq);
199 	mtx_init(&crypto_q_mtx, "crypto", "crypto op queues", MTX_DEF);
200 
201 	TAILQ_INIT(&crp_ret_q);
202 	TAILQ_INIT(&crp_ret_kq);
203 	mtx_init(&crypto_ret_q_mtx, "crypto", "crypto return queues", MTX_DEF);
204 
205 	cryptop_zone = uma_zcreate("cryptop", sizeof (struct cryptop),
206 				    0, 0, 0, 0,
207 				    UMA_ALIGN_PTR, UMA_ZONE_ZINIT);
208 	cryptodesc_zone = uma_zcreate("cryptodesc", sizeof (struct cryptodesc),
209 				    0, 0, 0, 0,
210 				    UMA_ALIGN_PTR, UMA_ZONE_ZINIT);
211 	if (cryptodesc_zone == NULL || cryptop_zone == NULL) {
212 		printf("crypto_init: cannot setup crypto zones\n");
213 		error = ENOMEM;
214 		goto bad;
215 	}
216 
217 	crypto_drivers_num = CRYPTO_DRIVERS_INITIAL;
218 	crypto_drivers = malloc(crypto_drivers_num *
219 	    sizeof(struct cryptocap), M_CRYPTO_DATA, M_NOWAIT | M_ZERO);
220 	if (crypto_drivers == NULL) {
221 		printf("crypto_init: cannot setup crypto drivers\n");
222 		error = ENOMEM;
223 		goto bad;
224 	}
225 
226 	error = kproc_create((void (*)(void *)) crypto_proc, NULL,
227 		    &cryptoproc, 0, 0, "crypto");
228 	if (error) {
229 		printf("crypto_init: cannot start crypto thread; error %d",
230 			error);
231 		goto bad;
232 	}
233 
234 	error = kproc_create((void (*)(void *)) crypto_ret_proc, NULL,
235 		    &cryptoretproc, 0, 0, "crypto returns");
236 	if (error) {
237 		printf("crypto_init: cannot start cryptoret thread; error %d",
238 			error);
239 		goto bad;
240 	}
241 	return 0;
242 bad:
243 	crypto_destroy();
244 	return error;
245 }
246 
247 /*
248  * Signal a crypto thread to terminate.  We use the driver
249  * table lock to synchronize the sleep/wakeups so that we
250  * are sure the threads have terminated before we release
251  * the data structures they use.  See crypto_finis below
252  * for the other half of this song-and-dance.
253  */
254 static void
255 crypto_terminate(struct proc **pp, void *q)
256 {
257 	struct proc *p;
258 
259 	mtx_assert(&crypto_drivers_mtx, MA_OWNED);
260 	p = *pp;
261 	*pp = NULL;
262 	if (p) {
263 		wakeup_one(q);
264 		PROC_LOCK(p);		/* NB: insure we don't miss wakeup */
265 		CRYPTO_DRIVER_UNLOCK();	/* let crypto_finis progress */
266 		msleep(p, &p->p_mtx, PWAIT, "crypto_destroy", 0);
267 		PROC_UNLOCK(p);
268 		CRYPTO_DRIVER_LOCK();
269 	}
270 }
271 
272 static void
273 crypto_destroy(void)
274 {
275 	/*
276 	 * Terminate any crypto threads.
277 	 */
278 	CRYPTO_DRIVER_LOCK();
279 	crypto_terminate(&cryptoproc, &crp_q);
280 	crypto_terminate(&cryptoretproc, &crp_ret_q);
281 	CRYPTO_DRIVER_UNLOCK();
282 
283 	/* XXX flush queues??? */
284 
285 	/*
286 	 * Reclaim dynamically allocated resources.
287 	 */
288 	if (crypto_drivers != NULL)
289 		free(crypto_drivers, M_CRYPTO_DATA);
290 
291 	if (cryptodesc_zone != NULL)
292 		uma_zdestroy(cryptodesc_zone);
293 	if (cryptop_zone != NULL)
294 		uma_zdestroy(cryptop_zone);
295 	mtx_destroy(&crypto_q_mtx);
296 	mtx_destroy(&crypto_ret_q_mtx);
297 	mtx_destroy(&crypto_drivers_mtx);
298 }
299 
300 static struct cryptocap *
301 crypto_checkdriver(u_int32_t hid)
302 {
303 	if (crypto_drivers == NULL)
304 		return NULL;
305 	return (hid >= crypto_drivers_num ? NULL : &crypto_drivers[hid]);
306 }
307 
308 /*
309  * Compare a driver's list of supported algorithms against another
310  * list; return non-zero if all algorithms are supported.
311  */
312 static int
313 driver_suitable(const struct cryptocap *cap, const struct cryptoini *cri)
314 {
315 	const struct cryptoini *cr;
316 
317 	/* See if all the algorithms are supported. */
318 	for (cr = cri; cr; cr = cr->cri_next)
319 		if (cap->cc_alg[cr->cri_alg] == 0)
320 			return 0;
321 	return 1;
322 }
323 
324 /*
325  * Select a driver for a new session that supports the specified
326  * algorithms and, optionally, is constrained according to the flags.
327  * The algorithm we use here is pretty stupid; just use the
328  * first driver that supports all the algorithms we need. If there
329  * are multiple drivers we choose the driver with the fewest active
330  * sessions.  We prefer hardware-backed drivers to software ones.
331  *
332  * XXX We need more smarts here (in real life too, but that's
333  * XXX another story altogether).
334  */
335 static struct cryptocap *
336 crypto_select_driver(const struct cryptoini *cri, int flags)
337 {
338 	struct cryptocap *cap, *best;
339 	int match, hid;
340 
341 	CRYPTO_DRIVER_ASSERT();
342 
343 	/*
344 	 * Look first for hardware crypto devices if permitted.
345 	 */
346 	if (flags & CRYPTOCAP_F_HARDWARE)
347 		match = CRYPTOCAP_F_HARDWARE;
348 	else
349 		match = CRYPTOCAP_F_SOFTWARE;
350 	best = NULL;
351 again:
352 	for (hid = 0; hid < crypto_drivers_num; hid++) {
353 		cap = &crypto_drivers[hid];
354 		/*
355 		 * If it's not initialized, is in the process of
356 		 * going away, or is not appropriate (hardware
357 		 * or software based on match), then skip.
358 		 */
359 		if (cap->cc_dev == NULL ||
360 		    (cap->cc_flags & CRYPTOCAP_F_CLEANUP) ||
361 		    (cap->cc_flags & match) == 0)
362 			continue;
363 
364 		/* verify all the algorithms are supported. */
365 		if (driver_suitable(cap, cri)) {
366 			if (best == NULL ||
367 			    cap->cc_sessions < best->cc_sessions)
368 				best = cap;
369 		}
370 	}
371 	if (best == NULL && match == CRYPTOCAP_F_HARDWARE &&
372 	    (flags & CRYPTOCAP_F_SOFTWARE)) {
373 		/* sort of an Algol 68-style for loop */
374 		match = CRYPTOCAP_F_SOFTWARE;
375 		goto again;
376 	}
377 	return best;
378 }
379 
380 /*
381  * Create a new session.  The crid argument specifies a crypto
382  * driver to use or constraints on a driver to select (hardware
383  * only, software only, either).  Whatever driver is selected
384  * must be capable of the requested crypto algorithms.
385  */
386 int
387 crypto_newsession(u_int64_t *sid, struct cryptoini *cri, int crid)
388 {
389 	struct cryptocap *cap;
390 	u_int32_t hid, lid;
391 	int err;
392 
393 	CRYPTO_DRIVER_LOCK();
394 	if ((crid & (CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE)) == 0) {
395 		/*
396 		 * Use specified driver; verify it is capable.
397 		 */
398 		cap = crypto_checkdriver(crid);
399 		if (cap != NULL && !driver_suitable(cap, cri))
400 			cap = NULL;
401 	} else {
402 		/*
403 		 * No requested driver; select based on crid flags.
404 		 */
405 		cap = crypto_select_driver(cri, crid);
406 		/*
407 		 * if NULL then can't do everything in one session.
408 		 * XXX Fix this. We need to inject a "virtual" session
409 		 * XXX layer right about here.
410 		 */
411 	}
412 	if (cap != NULL) {
413 		/* Call the driver initialization routine. */
414 		hid = cap - crypto_drivers;
415 		lid = hid;		/* Pass the driver ID. */
416 		err = CRYPTODEV_NEWSESSION(cap->cc_dev, &lid, cri);
417 		if (err == 0) {
418 			(*sid) = (cap->cc_flags & 0xff000000)
419 			       | (hid & 0x00ffffff);
420 			(*sid) <<= 32;
421 			(*sid) |= (lid & 0xffffffff);
422 			cap->cc_sessions++;
423 		} else
424 			CRYPTDEB("dev newsession failed");
425 	} else {
426 		CRYPTDEB("no driver");
427 		err = EINVAL;
428 	}
429 	CRYPTO_DRIVER_UNLOCK();
430 	return err;
431 }
432 
433 static void
434 crypto_remove(struct cryptocap *cap)
435 {
436 
437 	mtx_assert(&crypto_drivers_mtx, MA_OWNED);
438 	if (cap->cc_sessions == 0 && cap->cc_koperations == 0)
439 		bzero(cap, sizeof(*cap));
440 }
441 
442 /*
443  * Delete an existing session (or a reserved session on an unregistered
444  * driver).
445  */
446 int
447 crypto_freesession(u_int64_t sid)
448 {
449 	struct cryptocap *cap;
450 	u_int32_t hid;
451 	int err;
452 
453 	CRYPTO_DRIVER_LOCK();
454 
455 	if (crypto_drivers == NULL) {
456 		err = EINVAL;
457 		goto done;
458 	}
459 
460 	/* Determine two IDs. */
461 	hid = CRYPTO_SESID2HID(sid);
462 
463 	if (hid >= crypto_drivers_num) {
464 		err = ENOENT;
465 		goto done;
466 	}
467 	cap = &crypto_drivers[hid];
468 
469 	if (cap->cc_sessions)
470 		cap->cc_sessions--;
471 
472 	/* Call the driver cleanup routine, if available. */
473 	err = CRYPTODEV_FREESESSION(cap->cc_dev, sid);
474 
475 	if (cap->cc_flags & CRYPTOCAP_F_CLEANUP)
476 		crypto_remove(cap);
477 
478 done:
479 	CRYPTO_DRIVER_UNLOCK();
480 	return err;
481 }
482 
483 /*
484  * Return an unused driver id.  Used by drivers prior to registering
485  * support for the algorithms they handle.
486  */
487 int32_t
488 crypto_get_driverid(device_t dev, int flags)
489 {
490 	struct cryptocap *newdrv;
491 	int i;
492 
493 	if ((flags & (CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE)) == 0) {
494 		printf("%s: no flags specified when registering driver\n",
495 		    device_get_nameunit(dev));
496 		return -1;
497 	}
498 
499 	CRYPTO_DRIVER_LOCK();
500 
501 	for (i = 0; i < crypto_drivers_num; i++) {
502 		if (crypto_drivers[i].cc_dev == NULL &&
503 		    (crypto_drivers[i].cc_flags & CRYPTOCAP_F_CLEANUP) == 0) {
504 			break;
505 		}
506 	}
507 
508 	/* Out of entries, allocate some more. */
509 	if (i == crypto_drivers_num) {
510 		/* Be careful about wrap-around. */
511 		if (2 * crypto_drivers_num <= crypto_drivers_num) {
512 			CRYPTO_DRIVER_UNLOCK();
513 			printf("crypto: driver count wraparound!\n");
514 			return -1;
515 		}
516 
517 		newdrv = malloc(2 * crypto_drivers_num *
518 		    sizeof(struct cryptocap), M_CRYPTO_DATA, M_NOWAIT|M_ZERO);
519 		if (newdrv == NULL) {
520 			CRYPTO_DRIVER_UNLOCK();
521 			printf("crypto: no space to expand driver table!\n");
522 			return -1;
523 		}
524 
525 		bcopy(crypto_drivers, newdrv,
526 		    crypto_drivers_num * sizeof(struct cryptocap));
527 
528 		crypto_drivers_num *= 2;
529 
530 		free(crypto_drivers, M_CRYPTO_DATA);
531 		crypto_drivers = newdrv;
532 	}
533 
534 	/* NB: state is zero'd on free */
535 	crypto_drivers[i].cc_sessions = 1;	/* Mark */
536 	crypto_drivers[i].cc_dev = dev;
537 	crypto_drivers[i].cc_flags = flags;
538 	if (bootverbose)
539 		printf("crypto: assign %s driver id %u, flags %u\n",
540 		    device_get_nameunit(dev), i, flags);
541 
542 	CRYPTO_DRIVER_UNLOCK();
543 
544 	return i;
545 }
546 
547 /*
548  * Lookup a driver by name.  We match against the full device
549  * name and unit, and against just the name.  The latter gives
550  * us a simple widlcarding by device name.  On success return the
551  * driver/hardware identifier; otherwise return -1.
552  */
553 int
554 crypto_find_driver(const char *match)
555 {
556 	int i, len = strlen(match);
557 
558 	CRYPTO_DRIVER_LOCK();
559 	for (i = 0; i < crypto_drivers_num; i++) {
560 		device_t dev = crypto_drivers[i].cc_dev;
561 		if (dev == NULL ||
562 		    (crypto_drivers[i].cc_flags & CRYPTOCAP_F_CLEANUP))
563 			continue;
564 		if (strncmp(match, device_get_nameunit(dev), len) == 0 ||
565 		    strncmp(match, device_get_name(dev), len) == 0)
566 			break;
567 	}
568 	CRYPTO_DRIVER_UNLOCK();
569 	return i < crypto_drivers_num ? i : -1;
570 }
571 
572 /*
573  * Return the device_t for the specified driver or NULL
574  * if the driver identifier is invalid.
575  */
576 device_t
577 crypto_find_device_byhid(int hid)
578 {
579 	struct cryptocap *cap = crypto_checkdriver(hid);
580 	return cap != NULL ? cap->cc_dev : NULL;
581 }
582 
583 /*
584  * Return the device/driver capabilities.
585  */
586 int
587 crypto_getcaps(int hid)
588 {
589 	struct cryptocap *cap = crypto_checkdriver(hid);
590 	return cap != NULL ? cap->cc_flags : 0;
591 }
592 
593 /*
594  * Register support for a key-related algorithm.  This routine
595  * is called once for each algorithm supported a driver.
596  */
597 int
598 crypto_kregister(u_int32_t driverid, int kalg, u_int32_t flags)
599 {
600 	struct cryptocap *cap;
601 	int err;
602 
603 	CRYPTO_DRIVER_LOCK();
604 
605 	cap = crypto_checkdriver(driverid);
606 	if (cap != NULL &&
607 	    (CRK_ALGORITM_MIN <= kalg && kalg <= CRK_ALGORITHM_MAX)) {
608 		/*
609 		 * XXX Do some performance testing to determine placing.
610 		 * XXX We probably need an auxiliary data structure that
611 		 * XXX describes relative performances.
612 		 */
613 
614 		cap->cc_kalg[kalg] = flags | CRYPTO_ALG_FLAG_SUPPORTED;
615 		if (bootverbose)
616 			printf("crypto: %s registers key alg %u flags %u\n"
617 				, device_get_nameunit(cap->cc_dev)
618 				, kalg
619 				, flags
620 			);
621 		err = 0;
622 	} else
623 		err = EINVAL;
624 
625 	CRYPTO_DRIVER_UNLOCK();
626 	return err;
627 }
628 
629 /*
630  * Register support for a non-key-related algorithm.  This routine
631  * is called once for each such algorithm supported by a driver.
632  */
633 int
634 crypto_register(u_int32_t driverid, int alg, u_int16_t maxoplen,
635     u_int32_t flags)
636 {
637 	struct cryptocap *cap;
638 	int err;
639 
640 	CRYPTO_DRIVER_LOCK();
641 
642 	cap = crypto_checkdriver(driverid);
643 	/* NB: algorithms are in the range [1..max] */
644 	if (cap != NULL &&
645 	    (CRYPTO_ALGORITHM_MIN <= alg && alg <= CRYPTO_ALGORITHM_MAX)) {
646 		/*
647 		 * XXX Do some performance testing to determine placing.
648 		 * XXX We probably need an auxiliary data structure that
649 		 * XXX describes relative performances.
650 		 */
651 
652 		cap->cc_alg[alg] = flags | CRYPTO_ALG_FLAG_SUPPORTED;
653 		cap->cc_max_op_len[alg] = maxoplen;
654 		if (bootverbose)
655 			printf("crypto: %s registers alg %u flags %u maxoplen %u\n"
656 				, device_get_nameunit(cap->cc_dev)
657 				, alg
658 				, flags
659 				, maxoplen
660 			);
661 		cap->cc_sessions = 0;		/* Unmark */
662 		err = 0;
663 	} else
664 		err = EINVAL;
665 
666 	CRYPTO_DRIVER_UNLOCK();
667 	return err;
668 }
669 
670 static void
671 driver_finis(struct cryptocap *cap)
672 {
673 	u_int32_t ses, kops;
674 
675 	CRYPTO_DRIVER_ASSERT();
676 
677 	ses = cap->cc_sessions;
678 	kops = cap->cc_koperations;
679 	bzero(cap, sizeof(*cap));
680 	if (ses != 0 || kops != 0) {
681 		/*
682 		 * If there are pending sessions,
683 		 * just mark as invalid.
684 		 */
685 		cap->cc_flags |= CRYPTOCAP_F_CLEANUP;
686 		cap->cc_sessions = ses;
687 		cap->cc_koperations = kops;
688 	}
689 }
690 
691 /*
692  * Unregister a crypto driver. If there are pending sessions using it,
693  * leave enough information around so that subsequent calls using those
694  * sessions will correctly detect the driver has been unregistered and
695  * reroute requests.
696  */
697 int
698 crypto_unregister(u_int32_t driverid, int alg)
699 {
700 	struct cryptocap *cap;
701 	int i, err;
702 
703 	CRYPTO_DRIVER_LOCK();
704 	cap = crypto_checkdriver(driverid);
705 	if (cap != NULL &&
706 	    (CRYPTO_ALGORITHM_MIN <= alg && alg <= CRYPTO_ALGORITHM_MAX) &&
707 	    cap->cc_alg[alg] != 0) {
708 		cap->cc_alg[alg] = 0;
709 		cap->cc_max_op_len[alg] = 0;
710 
711 		/* Was this the last algorithm ? */
712 		for (i = 1; i <= CRYPTO_ALGORITHM_MAX; i++)
713 			if (cap->cc_alg[i] != 0)
714 				break;
715 
716 		if (i == CRYPTO_ALGORITHM_MAX + 1)
717 			driver_finis(cap);
718 		err = 0;
719 	} else
720 		err = EINVAL;
721 	CRYPTO_DRIVER_UNLOCK();
722 
723 	return err;
724 }
725 
726 /*
727  * Unregister all algorithms associated with a crypto driver.
728  * If there are pending sessions using it, leave enough information
729  * around so that subsequent calls using those sessions will
730  * correctly detect the driver has been unregistered and reroute
731  * requests.
732  */
733 int
734 crypto_unregister_all(u_int32_t driverid)
735 {
736 	struct cryptocap *cap;
737 	int err;
738 
739 	CRYPTO_DRIVER_LOCK();
740 	cap = crypto_checkdriver(driverid);
741 	if (cap != NULL) {
742 		driver_finis(cap);
743 		err = 0;
744 	} else
745 		err = EINVAL;
746 	CRYPTO_DRIVER_UNLOCK();
747 
748 	return err;
749 }
750 
751 /*
752  * Clear blockage on a driver.  The what parameter indicates whether
753  * the driver is now ready for cryptop's and/or cryptokop's.
754  */
755 int
756 crypto_unblock(u_int32_t driverid, int what)
757 {
758 	struct cryptocap *cap;
759 	int err;
760 
761 	CRYPTO_Q_LOCK();
762 	cap = crypto_checkdriver(driverid);
763 	if (cap != NULL) {
764 		if (what & CRYPTO_SYMQ)
765 			cap->cc_qblocked = 0;
766 		if (what & CRYPTO_ASYMQ)
767 			cap->cc_kqblocked = 0;
768 		if (crp_sleep)
769 			wakeup_one(&crp_q);
770 		err = 0;
771 	} else
772 		err = EINVAL;
773 	CRYPTO_Q_UNLOCK();
774 
775 	return err;
776 }
777 
778 /*
779  * Add a crypto request to a queue, to be processed by the kernel thread.
780  */
781 int
782 crypto_dispatch(struct cryptop *crp)
783 {
784 	struct cryptocap *cap;
785 	u_int32_t hid;
786 	int result;
787 
788 	cryptostats.cs_ops++;
789 
790 #ifdef CRYPTO_TIMING
791 	if (crypto_timing)
792 		binuptime(&crp->crp_tstamp);
793 #endif
794 
795 	hid = CRYPTO_SESID2HID(crp->crp_sid);
796 
797 	if ((crp->crp_flags & CRYPTO_F_BATCH) == 0) {
798 		/*
799 		 * Caller marked the request to be processed
800 		 * immediately; dispatch it directly to the
801 		 * driver unless the driver is currently blocked.
802 		 */
803 		cap = crypto_checkdriver(hid);
804 		/* Driver cannot disappeared when there is an active session. */
805 		KASSERT(cap != NULL, ("%s: Driver disappeared.", __func__));
806 		if (!cap->cc_qblocked) {
807 			result = crypto_invoke(cap, crp, 0);
808 			if (result != ERESTART)
809 				return (result);
810 			/*
811 			 * The driver ran out of resources, put the request on
812 			 * the queue.
813 			 */
814 		}
815 	}
816 	CRYPTO_Q_LOCK();
817 	TAILQ_INSERT_TAIL(&crp_q, crp, crp_next);
818 	if (crp_sleep)
819 		wakeup_one(&crp_q);
820 	CRYPTO_Q_UNLOCK();
821 	return 0;
822 }
823 
824 /*
825  * Add an asymetric crypto request to a queue,
826  * to be processed by the kernel thread.
827  */
828 int
829 crypto_kdispatch(struct cryptkop *krp)
830 {
831 	int error;
832 
833 	cryptostats.cs_kops++;
834 
835 	error = crypto_kinvoke(krp, krp->krp_crid);
836 	if (error == ERESTART) {
837 		CRYPTO_Q_LOCK();
838 		TAILQ_INSERT_TAIL(&crp_kq, krp, krp_next);
839 		if (crp_sleep)
840 			wakeup_one(&crp_q);
841 		CRYPTO_Q_UNLOCK();
842 		error = 0;
843 	}
844 	return error;
845 }
846 
847 /*
848  * Verify a driver is suitable for the specified operation.
849  */
850 static __inline int
851 kdriver_suitable(const struct cryptocap *cap, const struct cryptkop *krp)
852 {
853 	return (cap->cc_kalg[krp->krp_op] & CRYPTO_ALG_FLAG_SUPPORTED) != 0;
854 }
855 
856 /*
857  * Select a driver for an asym operation.  The driver must
858  * support the necessary algorithm.  The caller can constrain
859  * which device is selected with the flags parameter.  The
860  * algorithm we use here is pretty stupid; just use the first
861  * driver that supports the algorithms we need. If there are
862  * multiple suitable drivers we choose the driver with the
863  * fewest active operations.  We prefer hardware-backed
864  * drivers to software ones when either may be used.
865  */
866 static struct cryptocap *
867 crypto_select_kdriver(const struct cryptkop *krp, int flags)
868 {
869 	struct cryptocap *cap, *best, *blocked;
870 	int match, hid;
871 
872 	CRYPTO_DRIVER_ASSERT();
873 
874 	/*
875 	 * Look first for hardware crypto devices if permitted.
876 	 */
877 	if (flags & CRYPTOCAP_F_HARDWARE)
878 		match = CRYPTOCAP_F_HARDWARE;
879 	else
880 		match = CRYPTOCAP_F_SOFTWARE;
881 	best = NULL;
882 	blocked = NULL;
883 again:
884 	for (hid = 0; hid < crypto_drivers_num; hid++) {
885 		cap = &crypto_drivers[hid];
886 		/*
887 		 * If it's not initialized, is in the process of
888 		 * going away, or is not appropriate (hardware
889 		 * or software based on match), then skip.
890 		 */
891 		if (cap->cc_dev == NULL ||
892 		    (cap->cc_flags & CRYPTOCAP_F_CLEANUP) ||
893 		    (cap->cc_flags & match) == 0)
894 			continue;
895 
896 		/* verify all the algorithms are supported. */
897 		if (kdriver_suitable(cap, krp)) {
898 			if (best == NULL ||
899 			    cap->cc_koperations < best->cc_koperations)
900 				best = cap;
901 		}
902 	}
903 	if (best != NULL)
904 		return best;
905 	if (match == CRYPTOCAP_F_HARDWARE && (flags & CRYPTOCAP_F_SOFTWARE)) {
906 		/* sort of an Algol 68-style for loop */
907 		match = CRYPTOCAP_F_SOFTWARE;
908 		goto again;
909 	}
910 	return best;
911 }
912 
913 /*
914  * Dispatch an assymetric crypto request.
915  */
916 static int
917 crypto_kinvoke(struct cryptkop *krp, int crid)
918 {
919 	struct cryptocap *cap = NULL;
920 	int error;
921 
922 	KASSERT(krp != NULL, ("%s: krp == NULL", __func__));
923 	KASSERT(krp->krp_callback != NULL,
924 	    ("%s: krp->crp_callback == NULL", __func__));
925 
926 	CRYPTO_DRIVER_LOCK();
927 	if ((crid & (CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE)) == 0) {
928 		cap = crypto_checkdriver(crid);
929 		if (cap != NULL) {
930 			/*
931 			 * Driver present, it must support the necessary
932 			 * algorithm and, if s/w drivers are excluded,
933 			 * it must be registered as hardware-backed.
934 			 */
935 			if (!kdriver_suitable(cap, krp) ||
936 			    (!crypto_devallowsoft &&
937 			     (cap->cc_flags & CRYPTOCAP_F_HARDWARE) == 0))
938 				cap = NULL;
939 		}
940 	} else {
941 		/*
942 		 * No requested driver; select based on crid flags.
943 		 */
944 		if (!crypto_devallowsoft)	/* NB: disallow s/w drivers */
945 			crid &= ~CRYPTOCAP_F_SOFTWARE;
946 		cap = crypto_select_kdriver(krp, crid);
947 	}
948 	if (cap != NULL && !cap->cc_kqblocked) {
949 		krp->krp_hid = cap - crypto_drivers;
950 		cap->cc_koperations++;
951 		CRYPTO_DRIVER_UNLOCK();
952 		error = CRYPTODEV_KPROCESS(cap->cc_dev, krp, 0);
953 		CRYPTO_DRIVER_LOCK();
954 		if (error == ERESTART) {
955 			cap->cc_koperations--;
956 			CRYPTO_DRIVER_UNLOCK();
957 			return (error);
958 		}
959 	} else {
960 		/*
961 		 * NB: cap is !NULL if device is blocked; in
962 		 *     that case return ERESTART so the operation
963 		 *     is resubmitted if possible.
964 		 */
965 		error = (cap == NULL) ? ENODEV : ERESTART;
966 	}
967 	CRYPTO_DRIVER_UNLOCK();
968 
969 	if (error) {
970 		krp->krp_status = error;
971 		crypto_kdone(krp);
972 	}
973 	return 0;
974 }
975 
976 #ifdef CRYPTO_TIMING
977 static void
978 crypto_tstat(struct cryptotstat *ts, struct bintime *bt)
979 {
980 	struct bintime now, delta;
981 	struct timespec t;
982 	uint64_t u;
983 
984 	binuptime(&now);
985 	u = now.frac;
986 	delta.frac = now.frac - bt->frac;
987 	delta.sec = now.sec - bt->sec;
988 	if (u < delta.frac)
989 		delta.sec--;
990 	bintime2timespec(&delta, &t);
991 	timespecadd(&ts->acc, &t);
992 	if (timespeccmp(&t, &ts->min, <))
993 		ts->min = t;
994 	if (timespeccmp(&t, &ts->max, >))
995 		ts->max = t;
996 	ts->count++;
997 
998 	*bt = now;
999 }
1000 #endif
1001 
1002 /*
1003  * Dispatch a crypto request to the appropriate crypto devices.
1004  */
1005 static int
1006 crypto_invoke(struct cryptocap *cap, struct cryptop *crp, int hint)
1007 {
1008 
1009 	KASSERT(crp != NULL, ("%s: crp == NULL", __func__));
1010 	KASSERT(crp->crp_callback != NULL,
1011 	    ("%s: crp->crp_callback == NULL", __func__));
1012 	KASSERT(crp->crp_desc != NULL, ("%s: crp->crp_desc == NULL", __func__));
1013 
1014 #ifdef CRYPTO_TIMING
1015 	if (crypto_timing)
1016 		crypto_tstat(&cryptostats.cs_invoke, &crp->crp_tstamp);
1017 #endif
1018 	if (cap->cc_flags & CRYPTOCAP_F_CLEANUP) {
1019 		struct cryptodesc *crd;
1020 		u_int64_t nid;
1021 
1022 		/*
1023 		 * Driver has unregistered; migrate the session and return
1024 		 * an error to the caller so they'll resubmit the op.
1025 		 *
1026 		 * XXX: What if there are more already queued requests for this
1027 		 *      session?
1028 		 */
1029 		crypto_freesession(crp->crp_sid);
1030 
1031 		for (crd = crp->crp_desc; crd->crd_next; crd = crd->crd_next)
1032 			crd->CRD_INI.cri_next = &(crd->crd_next->CRD_INI);
1033 
1034 		/* XXX propagate flags from initial session? */
1035 		if (crypto_newsession(&nid, &(crp->crp_desc->CRD_INI),
1036 		    CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE) == 0)
1037 			crp->crp_sid = nid;
1038 
1039 		crp->crp_etype = EAGAIN;
1040 		crypto_done(crp);
1041 		return 0;
1042 	} else {
1043 		/*
1044 		 * Invoke the driver to process the request.
1045 		 */
1046 		return CRYPTODEV_PROCESS(cap->cc_dev, crp, hint);
1047 	}
1048 }
1049 
1050 /*
1051  * Release a set of crypto descriptors.
1052  */
1053 void
1054 crypto_freereq(struct cryptop *crp)
1055 {
1056 	struct cryptodesc *crd;
1057 
1058 	if (crp == NULL)
1059 		return;
1060 
1061 #ifdef DIAGNOSTIC
1062 	{
1063 		struct cryptop *crp2;
1064 
1065 		CRYPTO_Q_LOCK();
1066 		TAILQ_FOREACH(crp2, &crp_q, crp_next) {
1067 			KASSERT(crp2 != crp,
1068 			    ("Freeing cryptop from the crypto queue (%p).",
1069 			    crp));
1070 		}
1071 		CRYPTO_Q_UNLOCK();
1072 		CRYPTO_RETQ_LOCK();
1073 		TAILQ_FOREACH(crp2, &crp_ret_q, crp_next) {
1074 			KASSERT(crp2 != crp,
1075 			    ("Freeing cryptop from the return queue (%p).",
1076 			    crp));
1077 		}
1078 		CRYPTO_RETQ_UNLOCK();
1079 	}
1080 #endif
1081 
1082 	while ((crd = crp->crp_desc) != NULL) {
1083 		crp->crp_desc = crd->crd_next;
1084 		uma_zfree(cryptodesc_zone, crd);
1085 	}
1086 	uma_zfree(cryptop_zone, crp);
1087 }
1088 
1089 /*
1090  * Acquire a set of crypto descriptors.
1091  */
1092 struct cryptop *
1093 crypto_getreq(int num)
1094 {
1095 	struct cryptodesc *crd;
1096 	struct cryptop *crp;
1097 
1098 	crp = uma_zalloc(cryptop_zone, M_NOWAIT|M_ZERO);
1099 	if (crp != NULL) {
1100 		while (num--) {
1101 			crd = uma_zalloc(cryptodesc_zone, M_NOWAIT|M_ZERO);
1102 			if (crd == NULL) {
1103 				crypto_freereq(crp);
1104 				return NULL;
1105 			}
1106 
1107 			crd->crd_next = crp->crp_desc;
1108 			crp->crp_desc = crd;
1109 		}
1110 	}
1111 	return crp;
1112 }
1113 
1114 /*
1115  * Invoke the callback on behalf of the driver.
1116  */
1117 void
1118 crypto_done(struct cryptop *crp)
1119 {
1120 	KASSERT((crp->crp_flags & CRYPTO_F_DONE) == 0,
1121 		("crypto_done: op already done, flags 0x%x", crp->crp_flags));
1122 	crp->crp_flags |= CRYPTO_F_DONE;
1123 	if (crp->crp_etype != 0)
1124 		cryptostats.cs_errs++;
1125 #ifdef CRYPTO_TIMING
1126 	if (crypto_timing)
1127 		crypto_tstat(&cryptostats.cs_done, &crp->crp_tstamp);
1128 #endif
1129 	/*
1130 	 * CBIMM means unconditionally do the callback immediately;
1131 	 * CBIFSYNC means do the callback immediately only if the
1132 	 * operation was done synchronously.  Both are used to avoid
1133 	 * doing extraneous context switches; the latter is mostly
1134 	 * used with the software crypto driver.
1135 	 */
1136 	if ((crp->crp_flags & CRYPTO_F_CBIMM) ||
1137 	    ((crp->crp_flags & CRYPTO_F_CBIFSYNC) &&
1138 	     (CRYPTO_SESID2CAPS(crp->crp_sid) & CRYPTOCAP_F_SYNC))) {
1139 		/*
1140 		 * Do the callback directly.  This is ok when the
1141 		 * callback routine does very little (e.g. the
1142 		 * /dev/crypto callback method just does a wakeup).
1143 		 */
1144 #ifdef CRYPTO_TIMING
1145 		if (crypto_timing) {
1146 			/*
1147 			 * NB: We must copy the timestamp before
1148 			 * doing the callback as the cryptop is
1149 			 * likely to be reclaimed.
1150 			 */
1151 			struct bintime t = crp->crp_tstamp;
1152 			crypto_tstat(&cryptostats.cs_cb, &t);
1153 			crp->crp_callback(crp);
1154 			crypto_tstat(&cryptostats.cs_finis, &t);
1155 		} else
1156 #endif
1157 			crp->crp_callback(crp);
1158 	} else {
1159 		/*
1160 		 * Normal case; queue the callback for the thread.
1161 		 */
1162 		CRYPTO_RETQ_LOCK();
1163 		if (CRYPTO_RETQ_EMPTY())
1164 			wakeup_one(&crp_ret_q);	/* shared wait channel */
1165 		TAILQ_INSERT_TAIL(&crp_ret_q, crp, crp_next);
1166 		CRYPTO_RETQ_UNLOCK();
1167 	}
1168 }
1169 
1170 /*
1171  * Invoke the callback on behalf of the driver.
1172  */
1173 void
1174 crypto_kdone(struct cryptkop *krp)
1175 {
1176 	struct cryptocap *cap;
1177 
1178 	if (krp->krp_status != 0)
1179 		cryptostats.cs_kerrs++;
1180 	CRYPTO_DRIVER_LOCK();
1181 	/* XXX: What if driver is loaded in the meantime? */
1182 	if (krp->krp_hid < crypto_drivers_num) {
1183 		cap = &crypto_drivers[krp->krp_hid];
1184 		cap->cc_koperations--;
1185 		KASSERT(cap->cc_koperations >= 0, ("cc_koperations < 0"));
1186 		if (cap->cc_flags & CRYPTOCAP_F_CLEANUP)
1187 			crypto_remove(cap);
1188 	}
1189 	CRYPTO_DRIVER_UNLOCK();
1190 	CRYPTO_RETQ_LOCK();
1191 	if (CRYPTO_RETQ_EMPTY())
1192 		wakeup_one(&crp_ret_q);		/* shared wait channel */
1193 	TAILQ_INSERT_TAIL(&crp_ret_kq, krp, krp_next);
1194 	CRYPTO_RETQ_UNLOCK();
1195 }
1196 
1197 int
1198 crypto_getfeat(int *featp)
1199 {
1200 	int hid, kalg, feat = 0;
1201 
1202 	CRYPTO_DRIVER_LOCK();
1203 	for (hid = 0; hid < crypto_drivers_num; hid++) {
1204 		const struct cryptocap *cap = &crypto_drivers[hid];
1205 
1206 		if ((cap->cc_flags & CRYPTOCAP_F_SOFTWARE) &&
1207 		    !crypto_devallowsoft) {
1208 			continue;
1209 		}
1210 		for (kalg = 0; kalg < CRK_ALGORITHM_MAX; kalg++)
1211 			if (cap->cc_kalg[kalg] & CRYPTO_ALG_FLAG_SUPPORTED)
1212 				feat |=  1 << kalg;
1213 	}
1214 	CRYPTO_DRIVER_UNLOCK();
1215 	*featp = feat;
1216 	return (0);
1217 }
1218 
1219 /*
1220  * Terminate a thread at module unload.  The process that
1221  * initiated this is waiting for us to signal that we're gone;
1222  * wake it up and exit.  We use the driver table lock to insure
1223  * we don't do the wakeup before they're waiting.  There is no
1224  * race here because the waiter sleeps on the proc lock for the
1225  * thread so it gets notified at the right time because of an
1226  * extra wakeup that's done in exit1().
1227  */
1228 static void
1229 crypto_finis(void *chan)
1230 {
1231 	CRYPTO_DRIVER_LOCK();
1232 	wakeup_one(chan);
1233 	CRYPTO_DRIVER_UNLOCK();
1234 	kproc_exit(0);
1235 }
1236 
1237 /*
1238  * Crypto thread, dispatches crypto requests.
1239  */
1240 static void
1241 crypto_proc(void)
1242 {
1243 	struct cryptop *crp, *submit;
1244 	struct cryptkop *krp;
1245 	struct cryptocap *cap;
1246 	u_int32_t hid;
1247 	int result, hint;
1248 
1249 #if defined(__i386__) || defined(__amd64__)
1250 	fpu_kern_thread(FPU_KERN_NORMAL);
1251 #endif
1252 
1253 	CRYPTO_Q_LOCK();
1254 	for (;;) {
1255 		/*
1256 		 * Find the first element in the queue that can be
1257 		 * processed and look-ahead to see if multiple ops
1258 		 * are ready for the same driver.
1259 		 */
1260 		submit = NULL;
1261 		hint = 0;
1262 		TAILQ_FOREACH(crp, &crp_q, crp_next) {
1263 			hid = CRYPTO_SESID2HID(crp->crp_sid);
1264 			cap = crypto_checkdriver(hid);
1265 			/*
1266 			 * Driver cannot disappeared when there is an active
1267 			 * session.
1268 			 */
1269 			KASSERT(cap != NULL, ("%s:%u Driver disappeared.",
1270 			    __func__, __LINE__));
1271 			if (cap == NULL || cap->cc_dev == NULL) {
1272 				/* Op needs to be migrated, process it. */
1273 				if (submit == NULL)
1274 					submit = crp;
1275 				break;
1276 			}
1277 			if (!cap->cc_qblocked) {
1278 				if (submit != NULL) {
1279 					/*
1280 					 * We stop on finding another op,
1281 					 * regardless whether its for the same
1282 					 * driver or not.  We could keep
1283 					 * searching the queue but it might be
1284 					 * better to just use a per-driver
1285 					 * queue instead.
1286 					 */
1287 					if (CRYPTO_SESID2HID(submit->crp_sid) == hid)
1288 						hint = CRYPTO_HINT_MORE;
1289 					break;
1290 				} else {
1291 					submit = crp;
1292 					if ((submit->crp_flags & CRYPTO_F_BATCH) == 0)
1293 						break;
1294 					/* keep scanning for more are q'd */
1295 				}
1296 			}
1297 		}
1298 		if (submit != NULL) {
1299 			TAILQ_REMOVE(&crp_q, submit, crp_next);
1300 			hid = CRYPTO_SESID2HID(submit->crp_sid);
1301 			cap = crypto_checkdriver(hid);
1302 			KASSERT(cap != NULL, ("%s:%u Driver disappeared.",
1303 			    __func__, __LINE__));
1304 			result = crypto_invoke(cap, submit, hint);
1305 			if (result == ERESTART) {
1306 				/*
1307 				 * The driver ran out of resources, mark the
1308 				 * driver ``blocked'' for cryptop's and put
1309 				 * the request back in the queue.  It would
1310 				 * best to put the request back where we got
1311 				 * it but that's hard so for now we put it
1312 				 * at the front.  This should be ok; putting
1313 				 * it at the end does not work.
1314 				 */
1315 				/* XXX validate sid again? */
1316 				crypto_drivers[CRYPTO_SESID2HID(submit->crp_sid)].cc_qblocked = 1;
1317 				TAILQ_INSERT_HEAD(&crp_q, submit, crp_next);
1318 				cryptostats.cs_blocks++;
1319 			}
1320 		}
1321 
1322 		/* As above, but for key ops */
1323 		TAILQ_FOREACH(krp, &crp_kq, krp_next) {
1324 			cap = crypto_checkdriver(krp->krp_hid);
1325 			if (cap == NULL || cap->cc_dev == NULL) {
1326 				/*
1327 				 * Operation needs to be migrated, invalidate
1328 				 * the assigned device so it will reselect a
1329 				 * new one below.  Propagate the original
1330 				 * crid selection flags if supplied.
1331 				 */
1332 				krp->krp_hid = krp->krp_crid &
1333 				    (CRYPTOCAP_F_SOFTWARE|CRYPTOCAP_F_HARDWARE);
1334 				if (krp->krp_hid == 0)
1335 					krp->krp_hid =
1336 				    CRYPTOCAP_F_SOFTWARE|CRYPTOCAP_F_HARDWARE;
1337 				break;
1338 			}
1339 			if (!cap->cc_kqblocked)
1340 				break;
1341 		}
1342 		if (krp != NULL) {
1343 			TAILQ_REMOVE(&crp_kq, krp, krp_next);
1344 			result = crypto_kinvoke(krp, krp->krp_hid);
1345 			if (result == ERESTART) {
1346 				/*
1347 				 * The driver ran out of resources, mark the
1348 				 * driver ``blocked'' for cryptkop's and put
1349 				 * the request back in the queue.  It would
1350 				 * best to put the request back where we got
1351 				 * it but that's hard so for now we put it
1352 				 * at the front.  This should be ok; putting
1353 				 * it at the end does not work.
1354 				 */
1355 				/* XXX validate sid again? */
1356 				crypto_drivers[krp->krp_hid].cc_kqblocked = 1;
1357 				TAILQ_INSERT_HEAD(&crp_kq, krp, krp_next);
1358 				cryptostats.cs_kblocks++;
1359 			}
1360 		}
1361 
1362 		if (submit == NULL && krp == NULL) {
1363 			/*
1364 			 * Nothing more to be processed.  Sleep until we're
1365 			 * woken because there are more ops to process.
1366 			 * This happens either by submission or by a driver
1367 			 * becoming unblocked and notifying us through
1368 			 * crypto_unblock.  Note that when we wakeup we
1369 			 * start processing each queue again from the
1370 			 * front. It's not clear that it's important to
1371 			 * preserve this ordering since ops may finish
1372 			 * out of order if dispatched to different devices
1373 			 * and some become blocked while others do not.
1374 			 */
1375 			crp_sleep = 1;
1376 			msleep(&crp_q, &crypto_q_mtx, PWAIT, "crypto_wait", 0);
1377 			crp_sleep = 0;
1378 			if (cryptoproc == NULL)
1379 				break;
1380 			cryptostats.cs_intrs++;
1381 		}
1382 	}
1383 	CRYPTO_Q_UNLOCK();
1384 
1385 	crypto_finis(&crp_q);
1386 }
1387 
1388 /*
1389  * Crypto returns thread, does callbacks for processed crypto requests.
1390  * Callbacks are done here, rather than in the crypto drivers, because
1391  * callbacks typically are expensive and would slow interrupt handling.
1392  */
1393 static void
1394 crypto_ret_proc(void)
1395 {
1396 	struct cryptop *crpt;
1397 	struct cryptkop *krpt;
1398 
1399 	CRYPTO_RETQ_LOCK();
1400 	for (;;) {
1401 		/* Harvest return q's for completed ops */
1402 		crpt = TAILQ_FIRST(&crp_ret_q);
1403 		if (crpt != NULL)
1404 			TAILQ_REMOVE(&crp_ret_q, crpt, crp_next);
1405 
1406 		krpt = TAILQ_FIRST(&crp_ret_kq);
1407 		if (krpt != NULL)
1408 			TAILQ_REMOVE(&crp_ret_kq, krpt, krp_next);
1409 
1410 		if (crpt != NULL || krpt != NULL) {
1411 			CRYPTO_RETQ_UNLOCK();
1412 			/*
1413 			 * Run callbacks unlocked.
1414 			 */
1415 			if (crpt != NULL) {
1416 #ifdef CRYPTO_TIMING
1417 				if (crypto_timing) {
1418 					/*
1419 					 * NB: We must copy the timestamp before
1420 					 * doing the callback as the cryptop is
1421 					 * likely to be reclaimed.
1422 					 */
1423 					struct bintime t = crpt->crp_tstamp;
1424 					crypto_tstat(&cryptostats.cs_cb, &t);
1425 					crpt->crp_callback(crpt);
1426 					crypto_tstat(&cryptostats.cs_finis, &t);
1427 				} else
1428 #endif
1429 					crpt->crp_callback(crpt);
1430 			}
1431 			if (krpt != NULL)
1432 				krpt->krp_callback(krpt);
1433 			CRYPTO_RETQ_LOCK();
1434 		} else {
1435 			/*
1436 			 * Nothing more to be processed.  Sleep until we're
1437 			 * woken because there are more returns to process.
1438 			 */
1439 			msleep(&crp_ret_q, &crypto_ret_q_mtx, PWAIT,
1440 				"crypto_ret_wait", 0);
1441 			if (cryptoretproc == NULL)
1442 				break;
1443 			cryptostats.cs_rets++;
1444 		}
1445 	}
1446 	CRYPTO_RETQ_UNLOCK();
1447 
1448 	crypto_finis(&crp_ret_q);
1449 }
1450 
1451 #ifdef DDB
1452 static void
1453 db_show_drivers(void)
1454 {
1455 	int hid;
1456 
1457 	db_printf("%12s %4s %4s %8s %2s %2s\n"
1458 		, "Device"
1459 		, "Ses"
1460 		, "Kops"
1461 		, "Flags"
1462 		, "QB"
1463 		, "KB"
1464 	);
1465 	for (hid = 0; hid < crypto_drivers_num; hid++) {
1466 		const struct cryptocap *cap = &crypto_drivers[hid];
1467 		if (cap->cc_dev == NULL)
1468 			continue;
1469 		db_printf("%-12s %4u %4u %08x %2u %2u\n"
1470 		    , device_get_nameunit(cap->cc_dev)
1471 		    , cap->cc_sessions
1472 		    , cap->cc_koperations
1473 		    , cap->cc_flags
1474 		    , cap->cc_qblocked
1475 		    , cap->cc_kqblocked
1476 		);
1477 	}
1478 }
1479 
1480 DB_SHOW_COMMAND(crypto, db_show_crypto)
1481 {
1482 	struct cryptop *crp;
1483 
1484 	db_show_drivers();
1485 	db_printf("\n");
1486 
1487 	db_printf("%4s %8s %4s %4s %4s %4s %8s %8s\n",
1488 	    "HID", "Caps", "Ilen", "Olen", "Etype", "Flags",
1489 	    "Desc", "Callback");
1490 	TAILQ_FOREACH(crp, &crp_q, crp_next) {
1491 		db_printf("%4u %08x %4u %4u %4u %04x %8p %8p\n"
1492 		    , (int) CRYPTO_SESID2HID(crp->crp_sid)
1493 		    , (int) CRYPTO_SESID2CAPS(crp->crp_sid)
1494 		    , crp->crp_ilen, crp->crp_olen
1495 		    , crp->crp_etype
1496 		    , crp->crp_flags
1497 		    , crp->crp_desc
1498 		    , crp->crp_callback
1499 		);
1500 	}
1501 	if (!TAILQ_EMPTY(&crp_ret_q)) {
1502 		db_printf("\n%4s %4s %4s %8s\n",
1503 		    "HID", "Etype", "Flags", "Callback");
1504 		TAILQ_FOREACH(crp, &crp_ret_q, crp_next) {
1505 			db_printf("%4u %4u %04x %8p\n"
1506 			    , (int) CRYPTO_SESID2HID(crp->crp_sid)
1507 			    , crp->crp_etype
1508 			    , crp->crp_flags
1509 			    , crp->crp_callback
1510 			);
1511 		}
1512 	}
1513 }
1514 
1515 DB_SHOW_COMMAND(kcrypto, db_show_kcrypto)
1516 {
1517 	struct cryptkop *krp;
1518 
1519 	db_show_drivers();
1520 	db_printf("\n");
1521 
1522 	db_printf("%4s %5s %4s %4s %8s %4s %8s\n",
1523 	    "Op", "Status", "#IP", "#OP", "CRID", "HID", "Callback");
1524 	TAILQ_FOREACH(krp, &crp_kq, krp_next) {
1525 		db_printf("%4u %5u %4u %4u %08x %4u %8p\n"
1526 		    , krp->krp_op
1527 		    , krp->krp_status
1528 		    , krp->krp_iparams, krp->krp_oparams
1529 		    , krp->krp_crid, krp->krp_hid
1530 		    , krp->krp_callback
1531 		);
1532 	}
1533 	if (!TAILQ_EMPTY(&crp_ret_q)) {
1534 		db_printf("%4s %5s %8s %4s %8s\n",
1535 		    "Op", "Status", "CRID", "HID", "Callback");
1536 		TAILQ_FOREACH(krp, &crp_ret_kq, krp_next) {
1537 			db_printf("%4u %5u %08x %4u %8p\n"
1538 			    , krp->krp_op
1539 			    , krp->krp_status
1540 			    , krp->krp_crid, krp->krp_hid
1541 			    , krp->krp_callback
1542 			);
1543 		}
1544 	}
1545 }
1546 #endif
1547 
1548 int crypto_modevent(module_t mod, int type, void *unused);
1549 
1550 /*
1551  * Initialization code, both for static and dynamic loading.
1552  * Note this is not invoked with the usual MODULE_DECLARE
1553  * mechanism but instead is listed as a dependency by the
1554  * cryptosoft driver.  This guarantees proper ordering of
1555  * calls on module load/unload.
1556  */
1557 int
1558 crypto_modevent(module_t mod, int type, void *unused)
1559 {
1560 	int error = EINVAL;
1561 
1562 	switch (type) {
1563 	case MOD_LOAD:
1564 		error = crypto_init();
1565 		if (error == 0 && bootverbose)
1566 			printf("crypto: <crypto core>\n");
1567 		break;
1568 	case MOD_UNLOAD:
1569 		/*XXX disallow if active sessions */
1570 		error = 0;
1571 		crypto_destroy();
1572 		return 0;
1573 	}
1574 	return error;
1575 }
1576 MODULE_VERSION(crypto, 1);
1577 MODULE_DEPEND(crypto, zlib, 1, 1, 1);
1578