xref: /dflybsd-src/sys/opencrypto/crypto.c (revision d4b8aec4bb44a374c3e91969c1a7df6569da7be3)
1 /*	$FreeBSD: src/sys/opencrypto/crypto.c,v 1.28 2007/10/20 23:23:22 julian Exp $	*/
2 /*-
3  * Copyright (c) 2002-2006 Sam Leffler.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  */
25 
26 /*
27  * Cryptographic Subsystem.
28  *
29  * This code is derived from the Openbsd Cryptographic Framework (OCF)
30  * that has the copyright shown below.  Very little of the original
31  * code remains.
32  */
33 
34 /*-
35  * The author of this code is Angelos D. Keromytis (angelos@cis.upenn.edu)
36  *
37  * This code was written by Angelos D. Keromytis in Athens, Greece, in
38  * February 2000. Network Security Technologies Inc. (NSTI) kindly
39  * supported the development of this code.
40  *
41  * Copyright (c) 2000, 2001 Angelos D. Keromytis
42  *
43  * Permission to use, copy, and modify this software with or without fee
44  * is hereby granted, provided that this entire notice is included in
45  * all source code copies of any software which is or includes a copy or
46  * modification of this software.
47  *
48  * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
49  * IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
50  * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
51  * MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
52  * PURPOSE.
53  */
54 
55 #define	CRYPTO_TIMING				/* enable timing support */
56 
57 #include "opt_ddb.h"
58 
59 #include <sys/param.h>
60 #include <sys/systm.h>
61 #include <sys/eventhandler.h>
62 #include <sys/kernel.h>
63 #include <sys/kthread.h>
64 #include <sys/lock.h>
65 #include <sys/module.h>
66 #include <sys/malloc.h>
67 #include <sys/proc.h>
68 #include <sys/sysctl.h>
69 #include <sys/thread2.h>
70 #include <sys/mplock2.h>
71 
72 #include <vm/vm_zone.h>
73 
74 #include <ddb/ddb.h>
75 
76 #include <opencrypto/cryptodev.h>
77 #include <opencrypto/xform.h>			/* XXX for M_XDATA */
78 
79 #include <sys/kobj.h>
80 #include <sys/bus.h>
81 #include "cryptodev_if.h"
82 
83 /*
84  * Crypto drivers register themselves by allocating a slot in the
85  * crypto_drivers table with crypto_get_driverid() and then registering
86  * each algorithm they support with crypto_register() and crypto_kregister().
87  */
88 static	struct lock crypto_drivers_lock;	/* lock on driver table */
89 #define	CRYPTO_DRIVER_LOCK()	lockmgr(&crypto_drivers_lock, LK_EXCLUSIVE)
90 #define	CRYPTO_DRIVER_UNLOCK()	lockmgr(&crypto_drivers_lock, LK_RELEASE)
91 #define	CRYPTO_DRIVER_ASSERT()	KKASSERT(lockstatus(&crypto_drivers_lock, curthread) != 0)
92 
93 /*
94  * Crypto device/driver capabilities structure.
95  *
96  * Synchronization:
97  * (d) - protected by CRYPTO_DRIVER_LOCK()
98  * (q) - protected by CRYPTO_Q_LOCK()
99  * Not tagged fields are read-only.
100  */
101 struct cryptocap {
102 	device_t	cc_dev;			/* (d) device/driver */
103 	u_int32_t	cc_sessions;		/* (d) # of sessions */
104 	u_int32_t	cc_koperations;		/* (d) # os asym operations */
105 	/*
106 	 * Largest possible operator length (in bits) for each type of
107 	 * encryption algorithm. XXX not used
108 	 */
109 	u_int16_t	cc_max_op_len[CRYPTO_ALGORITHM_MAX + 1];
110 	u_int8_t	cc_alg[CRYPTO_ALGORITHM_MAX + 1];
111 	u_int8_t	cc_kalg[CRK_ALGORITHM_MAX + 1];
112 
113 	int		cc_flags;		/* (d) flags */
114 #define CRYPTOCAP_F_CLEANUP	0x80000000	/* needs resource cleanup */
115 	int		cc_qblocked;		/* (q) symmetric q blocked */
116 	int		cc_kqblocked;		/* (q) asymmetric q blocked */
117 };
118 static	struct cryptocap *crypto_drivers = NULL;
119 static	int crypto_drivers_num = 0;
120 
121 typedef struct crypto_tdinfo {
122 	TAILQ_HEAD(,cryptop)	crp_q;		/* request queues */
123 	TAILQ_HEAD(,cryptkop)	crp_kq;
124 	thread_t		crp_td;
125 	struct lock		crp_lock;
126 	int			crp_sleep;
127 } *crypto_tdinfo_t;
128 
129 /*
130  * There are two queues for crypto requests; one for symmetric (e.g.
131  * cipher) operations and one for asymmetric (e.g. MOD) operations.
132  * See below for how synchronization is handled.
133  * A single lock is used to lock access to both queues.  We could
134  * have one per-queue but having one simplifies handling of block/unblock
135  * operations.
136  */
137 static  struct crypto_tdinfo tdinfo_array[MAXCPU];
138 
139 #define	CRYPTO_Q_LOCK(tdinfo)	lockmgr(&tdinfo->crp_lock, LK_EXCLUSIVE)
140 #define	CRYPTO_Q_UNLOCK(tdinfo)	lockmgr(&tdinfo->crp_lock, LK_RELEASE)
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  * lock 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 lock crypto_ret_q_lock;
153 #define	CRYPTO_RETQ_LOCK()	lockmgr(&crypto_ret_q_lock, LK_EXCLUSIVE)
154 #define	CRYPTO_RETQ_UNLOCK()	lockmgr(&crypto_ret_q_lock, LK_RELEASE)
155 #define	CRYPTO_RETQ_EMPTY()	(TAILQ_EMPTY(&crp_ret_q) && TAILQ_EMPTY(&crp_ret_kq))
156 
157 /*
158  * Crypto op and desciptor data structures are allocated
159  * from separate private zones.
160  */
161 static	vm_zone_t cryptop_zone;
162 static	vm_zone_t cryptodesc_zone;
163 
164 int	crypto_userasymcrypto = 1;	/* userland may do asym crypto reqs */
165 SYSCTL_INT(_kern, OID_AUTO, userasymcrypto, CTLFLAG_RW,
166 	   &crypto_userasymcrypto, 0,
167 	   "Enable/disable user-mode access to asymmetric crypto support");
168 int	crypto_devallowsoft = 0;	/* only use hardware crypto for asym */
169 SYSCTL_INT(_kern, OID_AUTO, cryptodevallowsoft, CTLFLAG_RW,
170 	   &crypto_devallowsoft, 0,
171 	   "Enable/disable use of software asym crypto support");
172 int	crypto_altdispatch = 0;		/* dispatch to alternative cpu */
173 SYSCTL_INT(_kern, OID_AUTO, cryptoaltdispatch, CTLFLAG_RW,
174 	   &crypto_altdispatch, 0,
175 	   "Do not queue crypto op on current cpu");
176 
177 MALLOC_DEFINE(M_CRYPTO_DATA, "crypto", "crypto session records");
178 
179 static	void crypto_proc(void *dummy);
180 static	void crypto_ret_proc(void *dummy);
181 static	struct thread *cryptoretthread;
182 static	void crypto_destroy(void);
183 static	int crypto_invoke(struct cryptocap *cap, struct cryptop *crp, int hint);
184 static	int crypto_kinvoke(struct cryptkop *krp, int flags);
185 
186 static struct cryptostats cryptostats;
187 SYSCTL_STRUCT(_kern, OID_AUTO, crypto_stats, CTLFLAG_RW, &cryptostats,
188 	    cryptostats, "Crypto system statistics");
189 
190 #ifdef CRYPTO_TIMING
191 static	int crypto_timing = 0;
192 SYSCTL_INT(_debug, OID_AUTO, crypto_timing, CTLFLAG_RW,
193 	   &crypto_timing, 0, "Enable/disable crypto timing support");
194 #endif
195 
196 static int
197 crypto_init(void)
198 {
199 	crypto_tdinfo_t tdinfo;
200 	int error;
201 	int n;
202 
203 	lockinit(&crypto_drivers_lock, "crypto driver table", 0, LK_CANRECURSE);
204 
205 	TAILQ_INIT(&crp_ret_q);
206 	TAILQ_INIT(&crp_ret_kq);
207 	lockinit(&crypto_ret_q_lock, "crypto return queues", 0, LK_CANRECURSE);
208 
209 	cryptop_zone = zinit("cryptop", sizeof (struct cryptop), 0, 0, 1);
210 	cryptodesc_zone = zinit("cryptodesc", sizeof (struct cryptodesc),
211 				0, 0, 1);
212 	if (cryptodesc_zone == NULL || cryptop_zone == NULL) {
213 		kprintf("crypto_init: cannot setup crypto zones\n");
214 		error = ENOMEM;
215 		goto bad;
216 	}
217 
218 	crypto_drivers_num = CRYPTO_DRIVERS_INITIAL;
219 	crypto_drivers = kmalloc(crypto_drivers_num * sizeof(struct cryptocap),
220 				 M_CRYPTO_DATA, M_WAITOK | M_ZERO);
221 	if (crypto_drivers == NULL) {
222 		kprintf("crypto_init: cannot malloc driver table\n");
223 		error = ENOMEM;
224 		goto bad;
225 	}
226 
227 	for (n = 0; n < ncpus; ++n) {
228 		tdinfo = &tdinfo_array[n];
229 		TAILQ_INIT(&tdinfo->crp_q);
230 		TAILQ_INIT(&tdinfo->crp_kq);
231 		lockinit(&tdinfo->crp_lock, "crypto op queues",
232 			 0, LK_CANRECURSE);
233 		kthread_create_cpu(crypto_proc, tdinfo, &tdinfo->crp_td,
234 				   n, "crypto %d", n);
235 	}
236 	kthread_create(crypto_ret_proc, NULL,
237 		       &cryptoretthread, "crypto returns");
238 	return 0;
239 bad:
240 	crypto_destroy();
241 	return error;
242 }
243 
244 /*
245  * Signal a crypto thread to terminate.  We use the driver
246  * table lock to synchronize the sleep/wakeups so that we
247  * are sure the threads have terminated before we release
248  * the data structures they use.  See crypto_finis below
249  * for the other half of this song-and-dance.
250  */
251 static void
252 crypto_terminate(struct thread **tp, void *q)
253 {
254 	struct thread *t;
255 
256 	KKASSERT(lockstatus(&crypto_drivers_lock, curthread) != 0);
257 	t = *tp;
258 	*tp = NULL;
259 	if (t) {
260 		kprintf("crypto_terminate: start\n");
261 		wakeup_one(q);
262 		crit_enter();
263 		tsleep_interlock(t, 0);
264 		CRYPTO_DRIVER_UNLOCK();	/* let crypto_finis progress */
265 		crit_exit();
266 		tsleep(t, PINTERLOCKED, "crypto_destroy", 0);
267 		CRYPTO_DRIVER_LOCK();
268 		kprintf("crypto_terminate: end\n");
269 	}
270 }
271 
272 static void
273 crypto_destroy(void)
274 {
275 	crypto_tdinfo_t tdinfo;
276 	int n;
277 
278 	/*
279 	 * Terminate any crypto threads.
280 	 */
281 	CRYPTO_DRIVER_LOCK();
282 	for (n = 0; n < ncpus; ++n) {
283 		tdinfo = &tdinfo_array[n];
284 		crypto_terminate(&tdinfo->crp_td, &tdinfo->crp_q);
285 		lockuninit(&tdinfo->crp_lock);
286 	}
287 	crypto_terminate(&cryptoretthread, &crp_ret_q);
288 	CRYPTO_DRIVER_UNLOCK();
289 
290 	/* XXX flush queues??? */
291 
292 	/*
293 	 * Reclaim dynamically allocated resources.
294 	 */
295 	if (crypto_drivers != NULL)
296 		kfree(crypto_drivers, M_CRYPTO_DATA);
297 
298 	if (cryptodesc_zone != NULL)
299 		zdestroy(cryptodesc_zone);
300 	if (cryptop_zone != NULL)
301 		zdestroy(cryptop_zone);
302 	lockuninit(&crypto_ret_q_lock);
303 	lockuninit(&crypto_drivers_lock);
304 }
305 
306 static struct cryptocap *
307 crypto_checkdriver(u_int32_t hid)
308 {
309 	if (crypto_drivers == NULL)
310 		return NULL;
311 	return (hid >= crypto_drivers_num ? NULL : &crypto_drivers[hid]);
312 }
313 
314 /*
315  * Compare a driver's list of supported algorithms against another
316  * list; return non-zero if all algorithms are supported.
317  */
318 static int
319 driver_suitable(const struct cryptocap *cap, const struct cryptoini *cri)
320 {
321 	const struct cryptoini *cr;
322 
323 	/* See if all the algorithms are supported. */
324 	for (cr = cri; cr; cr = cr->cri_next)
325 		if (cap->cc_alg[cr->cri_alg] == 0)
326 			return 0;
327 	return 1;
328 }
329 
330 /*
331  * Select a driver for a new session that supports the specified
332  * algorithms and, optionally, is constrained according to the flags.
333  * The algorithm we use here is pretty stupid; just use the
334  * first driver that supports all the algorithms we need. If there
335  * are multiple drivers we choose the driver with the fewest active
336  * sessions.  We prefer hardware-backed drivers to software ones.
337  *
338  * XXX We need more smarts here (in real life too, but that's
339  * XXX another story altogether).
340  */
341 static struct cryptocap *
342 crypto_select_driver(const struct cryptoini *cri, int flags)
343 {
344 	struct cryptocap *cap, *best;
345 	int match, hid;
346 
347 	CRYPTO_DRIVER_ASSERT();
348 
349 	/*
350 	 * Look first for hardware crypto devices if permitted.
351 	 */
352 	if (flags & CRYPTOCAP_F_HARDWARE)
353 		match = CRYPTOCAP_F_HARDWARE;
354 	else
355 		match = CRYPTOCAP_F_SOFTWARE;
356 	best = NULL;
357 again:
358 	for (hid = 0; hid < crypto_drivers_num; hid++) {
359 		cap = &crypto_drivers[hid];
360 		/*
361 		 * If it's not initialized, is in the process of
362 		 * going away, or is not appropriate (hardware
363 		 * or software based on match), then skip.
364 		 */
365 		if (cap->cc_dev == NULL ||
366 		    (cap->cc_flags & CRYPTOCAP_F_CLEANUP) ||
367 		    (cap->cc_flags & match) == 0)
368 			continue;
369 
370 		/* verify all the algorithms are supported. */
371 		if (driver_suitable(cap, cri)) {
372 			if (best == NULL ||
373 			    cap->cc_sessions < best->cc_sessions)
374 				best = cap;
375 		}
376 	}
377 	if (best != NULL)
378 		return best;
379 	if (match == CRYPTOCAP_F_HARDWARE && (flags & CRYPTOCAP_F_SOFTWARE)) {
380 		/* sort of an Algol 68-style for loop */
381 		match = CRYPTOCAP_F_SOFTWARE;
382 		goto again;
383 	}
384 	return best;
385 }
386 
387 /*
388  * Create a new session.  The crid argument specifies a crypto
389  * driver to use or constraints on a driver to select (hardware
390  * only, software only, either).  Whatever driver is selected
391  * must be capable of the requested crypto algorithms.
392  */
393 int
394 crypto_newsession(u_int64_t *sid, struct cryptoini *cri, int crid)
395 {
396 	struct cryptocap *cap;
397 	u_int32_t hid, lid;
398 	int err;
399 
400 	CRYPTO_DRIVER_LOCK();
401 	if ((crid & (CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE)) == 0) {
402 		/*
403 		 * Use specified driver; verify it is capable.
404 		 */
405 		cap = crypto_checkdriver(crid);
406 		if (cap != NULL && !driver_suitable(cap, cri))
407 			cap = NULL;
408 	} else {
409 		/*
410 		 * No requested driver; select based on crid flags.
411 		 */
412 		cap = crypto_select_driver(cri, crid);
413 		/*
414 		 * if NULL then can't do everything in one session.
415 		 * XXX Fix this. We need to inject a "virtual" session
416 		 * XXX layer right about here.
417 		 */
418 	}
419 	if (cap != NULL) {
420 		/* Call the driver initialization routine. */
421 		hid = cap - crypto_drivers;
422 		lid = hid;		/* Pass the driver ID. */
423 		err = CRYPTODEV_NEWSESSION(cap->cc_dev, &lid, cri);
424 		if (err == 0) {
425 			(*sid) = (cap->cc_flags & 0xff000000)
426 			       | (hid & 0x00ffffff);
427 			(*sid) <<= 32;
428 			(*sid) |= (lid & 0xffffffff);
429 			cap->cc_sessions++;
430 		}
431 	} else
432 		err = EINVAL;
433 	CRYPTO_DRIVER_UNLOCK();
434 	return err;
435 }
436 
437 static void
438 crypto_remove(struct cryptocap *cap)
439 {
440 
441 	KKASSERT(lockstatus(&crypto_drivers_lock, curthread) != 0);
442 	if (cap->cc_sessions == 0 && cap->cc_koperations == 0)
443 		bzero(cap, sizeof(*cap));
444 }
445 
446 /*
447  * Delete an existing session (or a reserved session on an unregistered
448  * driver).
449  */
450 int
451 crypto_freesession(u_int64_t sid)
452 {
453 	struct cryptocap *cap;
454 	u_int32_t hid;
455 	int err;
456 
457 	CRYPTO_DRIVER_LOCK();
458 
459 	if (crypto_drivers == NULL) {
460 		err = EINVAL;
461 		goto done;
462 	}
463 
464 	/* Determine two IDs. */
465 	hid = CRYPTO_SESID2HID(sid);
466 
467 	if (hid >= crypto_drivers_num) {
468 		err = ENOENT;
469 		goto done;
470 	}
471 	cap = &crypto_drivers[hid];
472 
473 	if (cap->cc_sessions)
474 		cap->cc_sessions--;
475 
476 	/* Call the driver cleanup routine, if available. */
477 	err = CRYPTODEV_FREESESSION(cap->cc_dev, sid);
478 
479 	if (cap->cc_flags & CRYPTOCAP_F_CLEANUP)
480 		crypto_remove(cap);
481 
482 done:
483 	CRYPTO_DRIVER_UNLOCK();
484 	return err;
485 }
486 
487 /*
488  * Return an unused driver id.  Used by drivers prior to registering
489  * support for the algorithms they handle.
490  */
491 int32_t
492 crypto_get_driverid(device_t dev, int flags)
493 {
494 	struct cryptocap *newdrv;
495 	int i;
496 
497 	if ((flags & (CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE)) == 0) {
498 		kprintf("%s: no flags specified when registering driver\n",
499 		    device_get_nameunit(dev));
500 		return -1;
501 	}
502 
503 	CRYPTO_DRIVER_LOCK();
504 
505 	for (i = 0; i < crypto_drivers_num; i++) {
506 		if (crypto_drivers[i].cc_dev == NULL &&
507 		    (crypto_drivers[i].cc_flags & CRYPTOCAP_F_CLEANUP) == 0) {
508 			break;
509 		}
510 	}
511 
512 	/* Out of entries, allocate some more. */
513 	if (i == crypto_drivers_num) {
514 		/* Be careful about wrap-around. */
515 		if (2 * crypto_drivers_num <= crypto_drivers_num) {
516 			CRYPTO_DRIVER_UNLOCK();
517 			kprintf("crypto: driver count wraparound!\n");
518 			return -1;
519 		}
520 
521 		newdrv = kmalloc(2 * crypto_drivers_num *
522 				 sizeof(struct cryptocap),
523 				 M_CRYPTO_DATA, M_WAITOK|M_ZERO);
524 		if (newdrv == NULL) {
525 			CRYPTO_DRIVER_UNLOCK();
526 			kprintf("crypto: no space to expand driver table!\n");
527 			return -1;
528 		}
529 
530 		bcopy(crypto_drivers, newdrv,
531 		    crypto_drivers_num * sizeof(struct cryptocap));
532 
533 		crypto_drivers_num *= 2;
534 
535 		kfree(crypto_drivers, M_CRYPTO_DATA);
536 		crypto_drivers = newdrv;
537 	}
538 
539 	/* NB: state is zero'd on free */
540 	crypto_drivers[i].cc_sessions = 1;	/* Mark */
541 	crypto_drivers[i].cc_dev = dev;
542 	crypto_drivers[i].cc_flags = flags;
543 	if (bootverbose)
544 		kprintf("crypto: assign %s driver id %u, flags %u\n",
545 		    device_get_nameunit(dev), i, flags);
546 
547 	CRYPTO_DRIVER_UNLOCK();
548 
549 	return i;
550 }
551 
552 /*
553  * Lookup a driver by name.  We match against the full device
554  * name and unit, and against just the name.  The latter gives
555  * us a simple widlcarding by device name.  On success return the
556  * driver/hardware identifier; otherwise return -1.
557  */
558 int
559 crypto_find_driver(const char *match)
560 {
561 	int i, len = strlen(match);
562 
563 	CRYPTO_DRIVER_LOCK();
564 	for (i = 0; i < crypto_drivers_num; i++) {
565 		device_t dev = crypto_drivers[i].cc_dev;
566 		if (dev == NULL ||
567 		    (crypto_drivers[i].cc_flags & CRYPTOCAP_F_CLEANUP))
568 			continue;
569 		if (strncmp(match, device_get_nameunit(dev), len) == 0 ||
570 		    strncmp(match, device_get_name(dev), len) == 0)
571 			break;
572 	}
573 	CRYPTO_DRIVER_UNLOCK();
574 	return i < crypto_drivers_num ? i : -1;
575 }
576 
577 /*
578  * Return the device_t for the specified driver or NULL
579  * if the driver identifier is invalid.
580  */
581 device_t
582 crypto_find_device_byhid(int hid)
583 {
584 	struct cryptocap *cap = crypto_checkdriver(hid);
585 	return cap != NULL ? cap->cc_dev : NULL;
586 }
587 
588 /*
589  * Return the device/driver capabilities.
590  */
591 int
592 crypto_getcaps(int hid)
593 {
594 	struct cryptocap *cap = crypto_checkdriver(hid);
595 	return cap != NULL ? cap->cc_flags : 0;
596 }
597 
598 /*
599  * Register support for a key-related algorithm.  This routine
600  * is called once for each algorithm supported a driver.
601  */
602 int
603 crypto_kregister(u_int32_t driverid, int kalg, u_int32_t flags)
604 {
605 	struct cryptocap *cap;
606 	int err;
607 
608 	CRYPTO_DRIVER_LOCK();
609 
610 	cap = crypto_checkdriver(driverid);
611 	if (cap != NULL &&
612 	    (CRK_ALGORITM_MIN <= kalg && kalg <= CRK_ALGORITHM_MAX)) {
613 		/*
614 		 * XXX Do some performance testing to determine placing.
615 		 * XXX We probably need an auxiliary data structure that
616 		 * XXX describes relative performances.
617 		 */
618 
619 		cap->cc_kalg[kalg] = flags | CRYPTO_ALG_FLAG_SUPPORTED;
620 		if (bootverbose)
621 			kprintf("crypto: %s registers key alg %u flags %u\n"
622 				, device_get_nameunit(cap->cc_dev)
623 				, kalg
624 				, flags
625 			);
626 
627 		err = 0;
628 	} else
629 		err = EINVAL;
630 
631 	CRYPTO_DRIVER_UNLOCK();
632 	return err;
633 }
634 
635 /*
636  * Register support for a non-key-related algorithm.  This routine
637  * is called once for each such algorithm supported by a driver.
638  */
639 int
640 crypto_register(u_int32_t driverid, int alg, u_int16_t maxoplen,
641 		u_int32_t flags)
642 {
643 	struct cryptocap *cap;
644 	int err;
645 
646 	CRYPTO_DRIVER_LOCK();
647 
648 	cap = crypto_checkdriver(driverid);
649 	/* NB: algorithms are in the range [1..max] */
650 	if (cap != NULL &&
651 	    (CRYPTO_ALGORITHM_MIN <= alg && alg <= CRYPTO_ALGORITHM_MAX)) {
652 		/*
653 		 * XXX Do some performance testing to determine placing.
654 		 * XXX We probably need an auxiliary data structure that
655 		 * XXX describes relative performances.
656 		 */
657 
658 		cap->cc_alg[alg] = flags | CRYPTO_ALG_FLAG_SUPPORTED;
659 		cap->cc_max_op_len[alg] = maxoplen;
660 		if (bootverbose)
661 			kprintf("crypto: %s registers alg %u flags %u maxoplen %u\n"
662 				, device_get_nameunit(cap->cc_dev)
663 				, alg
664 				, flags
665 				, maxoplen
666 			);
667 		cap->cc_sessions = 0;		/* Unmark */
668 		err = 0;
669 	} else
670 		err = EINVAL;
671 
672 	CRYPTO_DRIVER_UNLOCK();
673 	return err;
674 }
675 
676 static void
677 driver_finis(struct cryptocap *cap)
678 {
679 	u_int32_t ses, kops;
680 
681 	CRYPTO_DRIVER_ASSERT();
682 
683 	ses = cap->cc_sessions;
684 	kops = cap->cc_koperations;
685 	bzero(cap, sizeof(*cap));
686 	if (ses != 0 || kops != 0) {
687 		/*
688 		 * If there are pending sessions,
689 		 * just mark as invalid.
690 		 */
691 		cap->cc_flags |= CRYPTOCAP_F_CLEANUP;
692 		cap->cc_sessions = ses;
693 		cap->cc_koperations = kops;
694 	}
695 }
696 
697 /*
698  * Unregister a crypto driver. If there are pending sessions using it,
699  * leave enough information around so that subsequent calls using those
700  * sessions will correctly detect the driver has been unregistered and
701  * reroute requests.
702  */
703 int
704 crypto_unregister(u_int32_t driverid, int alg)
705 {
706 	struct cryptocap *cap;
707 	int i, err;
708 
709 	CRYPTO_DRIVER_LOCK();
710 	cap = crypto_checkdriver(driverid);
711 	if (cap != NULL &&
712 	    (CRYPTO_ALGORITHM_MIN <= alg && alg <= CRYPTO_ALGORITHM_MAX) &&
713 	    cap->cc_alg[alg] != 0) {
714 		cap->cc_alg[alg] = 0;
715 		cap->cc_max_op_len[alg] = 0;
716 
717 		/* Was this the last algorithm ? */
718 		for (i = 1; i <= CRYPTO_ALGORITHM_MAX; i++) {
719 			if (cap->cc_alg[i] != 0)
720 				break;
721 		}
722 
723 		if (i == CRYPTO_ALGORITHM_MAX + 1)
724 			driver_finis(cap);
725 		err = 0;
726 	} else {
727 		err = EINVAL;
728 	}
729 	CRYPTO_DRIVER_UNLOCK();
730 
731 	return err;
732 }
733 
734 /*
735  * Unregister all algorithms associated with a crypto driver.
736  * If there are pending sessions using it, leave enough information
737  * around so that subsequent calls using those sessions will
738  * correctly detect the driver has been unregistered and reroute
739  * requests.
740  */
741 int
742 crypto_unregister_all(u_int32_t driverid)
743 {
744 	struct cryptocap *cap;
745 	int err;
746 
747 	CRYPTO_DRIVER_LOCK();
748 	cap = crypto_checkdriver(driverid);
749 	if (cap != NULL) {
750 		driver_finis(cap);
751 		err = 0;
752 	} else {
753 		err = EINVAL;
754 	}
755 	CRYPTO_DRIVER_UNLOCK();
756 
757 	return err;
758 }
759 
760 /*
761  * Clear blockage on a driver.  The what parameter indicates whether
762  * the driver is now ready for cryptop's and/or cryptokop's.
763  */
764 int
765 crypto_unblock(u_int32_t driverid, int what)
766 {
767 	crypto_tdinfo_t tdinfo;
768 	struct cryptocap *cap;
769 	int err;
770 	int n;
771 
772 	CRYPTO_DRIVER_LOCK();
773 	cap = crypto_checkdriver(driverid);
774 	if (cap != NULL) {
775 		if (what & CRYPTO_SYMQ)
776 			cap->cc_qblocked = 0;
777 		if (what & CRYPTO_ASYMQ)
778 			cap->cc_kqblocked = 0;
779 		for (n = 0; n < ncpus; ++n) {
780 			tdinfo = &tdinfo_array[n];
781 			CRYPTO_Q_LOCK(tdinfo);
782 			if (tdinfo[n].crp_sleep)
783 				wakeup_one(&tdinfo->crp_q);
784 			CRYPTO_Q_UNLOCK(tdinfo);
785 		}
786 		err = 0;
787 	} else {
788 		err = EINVAL;
789 	}
790 	CRYPTO_DRIVER_UNLOCK();
791 
792 	return err;
793 }
794 
795 static volatile int dispatch_rover;
796 
797 /*
798  * Add a crypto request to a queue, to be processed by the kernel thread.
799  */
800 int
801 crypto_dispatch(struct cryptop *crp)
802 {
803 	crypto_tdinfo_t tdinfo;
804 	struct cryptocap *cap;
805 	u_int32_t hid;
806 	int result;
807 	int n;
808 
809 	cryptostats.cs_ops++;
810 
811 #ifdef CRYPTO_TIMING
812 	if (crypto_timing)
813 		nanouptime(&crp->crp_tstamp);
814 #endif
815 
816 	hid = CRYPTO_SESID2HID(crp->crp_sid);
817 
818 	/*
819 	 * Dispatch the crypto op directly to the driver if the caller
820 	 * marked the request to be processed immediately or this is
821 	 * a synchronous callback chain occuring from within a crypto
822 	 * processing thread.
823 	 *
824 	 * Fall through to queueing the driver is blocked.
825 	 */
826 	if ((crp->crp_flags & CRYPTO_F_BATCH) == 0 ||
827 	    (curthread->td_flags & TDF_CRYPTO)) {
828 		cap = crypto_checkdriver(hid);
829 		/* Driver cannot disappeared when there is an active session. */
830 		KASSERT(cap != NULL, ("%s: Driver disappeared.", __func__));
831 		if (!cap->cc_qblocked) {
832 			result = crypto_invoke(cap, crp, 0);
833 			if (result != ERESTART)
834 				return (result);
835 			/*
836 			 * The driver ran out of resources, put the request on
837 			 * the queue.
838 			 */
839 		}
840 	}
841 
842 	/*
843 	 * Dispatch to a cpu for action if possible.  Dispatch to a different
844 	 * cpu than the current cpu.
845 	 */
846 	if (CRYPTO_SESID2CAPS(crp->crp_sid) & CRYPTOCAP_F_SMP) {
847 		n = atomic_fetchadd_int(&dispatch_rover, 1) & 255;
848 		if (crypto_altdispatch && mycpu->gd_cpuid == n)
849 			++n;
850 		n = n % ncpus;
851 	} else {
852 		n = 0;
853 	}
854 	tdinfo = &tdinfo_array[n];
855 
856 	CRYPTO_Q_LOCK(tdinfo);
857 	TAILQ_INSERT_TAIL(&tdinfo->crp_q, crp, crp_next);
858 	if (tdinfo->crp_sleep)
859 		wakeup_one(&tdinfo->crp_q);
860 	CRYPTO_Q_UNLOCK(tdinfo);
861 	return 0;
862 }
863 
864 /*
865  * Add an asymetric crypto request to a queue,
866  * to be processed by the kernel thread.
867  */
868 int
869 crypto_kdispatch(struct cryptkop *krp)
870 {
871 	crypto_tdinfo_t tdinfo;
872 	int error;
873 	int n;
874 
875 	cryptostats.cs_kops++;
876 
877 #if 0
878 	/* not sure how to test F_SMP here */
879 	n = atomic_fetchadd_int(&dispatch_rover, 1) & 255;
880 	n = n % ncpus;
881 #endif
882 	n = 0;
883 	tdinfo = &tdinfo_array[n];
884 
885 	error = crypto_kinvoke(krp, krp->krp_crid);
886 
887 	if (error == ERESTART) {
888 		CRYPTO_Q_LOCK(tdinfo);
889 		TAILQ_INSERT_TAIL(&tdinfo->crp_kq, krp, krp_next);
890 		if (tdinfo->crp_sleep)
891 			wakeup_one(&tdinfo->crp_q);
892 		CRYPTO_Q_UNLOCK(tdinfo);
893 		error = 0;
894 	}
895 	return error;
896 }
897 
898 /*
899  * Verify a driver is suitable for the specified operation.
900  */
901 static __inline int
902 kdriver_suitable(const struct cryptocap *cap, const struct cryptkop *krp)
903 {
904 	return (cap->cc_kalg[krp->krp_op] & CRYPTO_ALG_FLAG_SUPPORTED) != 0;
905 }
906 
907 /*
908  * Select a driver for an asym operation.  The driver must
909  * support the necessary algorithm.  The caller can constrain
910  * which device is selected with the flags parameter.  The
911  * algorithm we use here is pretty stupid; just use the first
912  * driver that supports the algorithms we need. If there are
913  * multiple suitable drivers we choose the driver with the
914  * fewest active operations.  We prefer hardware-backed
915  * drivers to software ones when either may be used.
916  */
917 static struct cryptocap *
918 crypto_select_kdriver(const struct cryptkop *krp, int flags)
919 {
920 	struct cryptocap *cap, *best, *blocked;
921 	int match, hid;
922 
923 	CRYPTO_DRIVER_ASSERT();
924 
925 	/*
926 	 * Look first for hardware crypto devices if permitted.
927 	 */
928 	if (flags & CRYPTOCAP_F_HARDWARE)
929 		match = CRYPTOCAP_F_HARDWARE;
930 	else
931 		match = CRYPTOCAP_F_SOFTWARE;
932 	best = NULL;
933 	blocked = NULL;
934 again:
935 	for (hid = 0; hid < crypto_drivers_num; hid++) {
936 		cap = &crypto_drivers[hid];
937 		/*
938 		 * If it's not initialized, is in the process of
939 		 * going away, or is not appropriate (hardware
940 		 * or software based on match), then skip.
941 		 */
942 		if (cap->cc_dev == NULL ||
943 		    (cap->cc_flags & CRYPTOCAP_F_CLEANUP) ||
944 		    (cap->cc_flags & match) == 0)
945 			continue;
946 
947 		/* verify all the algorithms are supported. */
948 		if (kdriver_suitable(cap, krp)) {
949 			if (best == NULL ||
950 			    cap->cc_koperations < best->cc_koperations)
951 				best = cap;
952 		}
953 	}
954 	if (best != NULL)
955 		return best;
956 	if (match == CRYPTOCAP_F_HARDWARE && (flags & CRYPTOCAP_F_SOFTWARE)) {
957 		/* sort of an Algol 68-style for loop */
958 		match = CRYPTOCAP_F_SOFTWARE;
959 		goto again;
960 	}
961 	return best;
962 }
963 
964 /*
965  * Dispatch an assymetric crypto request.
966  */
967 static int
968 crypto_kinvoke(struct cryptkop *krp, int crid)
969 {
970 	struct cryptocap *cap = NULL;
971 	int error;
972 
973 	KASSERT(krp != NULL, ("%s: krp == NULL", __func__));
974 	KASSERT(krp->krp_callback != NULL,
975 	    ("%s: krp->crp_callback == NULL", __func__));
976 
977 	CRYPTO_DRIVER_LOCK();
978 	if ((crid & (CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE)) == 0) {
979 		cap = crypto_checkdriver(crid);
980 		if (cap != NULL) {
981 			/*
982 			 * Driver present, it must support the necessary
983 			 * algorithm and, if s/w drivers are excluded,
984 			 * it must be registered as hardware-backed.
985 			 */
986 			if (!kdriver_suitable(cap, krp) ||
987 			    (!crypto_devallowsoft &&
988 			     (cap->cc_flags & CRYPTOCAP_F_HARDWARE) == 0))
989 				cap = NULL;
990 		}
991 	} else {
992 		/*
993 		 * No requested driver; select based on crid flags.
994 		 */
995 		if (!crypto_devallowsoft)	/* NB: disallow s/w drivers */
996 			crid &= ~CRYPTOCAP_F_SOFTWARE;
997 		cap = crypto_select_kdriver(krp, crid);
998 	}
999 	if (cap != NULL && !cap->cc_kqblocked) {
1000 		krp->krp_hid = cap - crypto_drivers;
1001 		cap->cc_koperations++;
1002 		CRYPTO_DRIVER_UNLOCK();
1003 		error = CRYPTODEV_KPROCESS(cap->cc_dev, krp, 0);
1004 		CRYPTO_DRIVER_LOCK();
1005 		if (error == ERESTART) {
1006 			cap->cc_koperations--;
1007 			CRYPTO_DRIVER_UNLOCK();
1008 			return (error);
1009 		}
1010 	} else {
1011 		/*
1012 		 * NB: cap is !NULL if device is blocked; in
1013 		 *     that case return ERESTART so the operation
1014 		 *     is resubmitted if possible.
1015 		 */
1016 		error = (cap == NULL) ? ENODEV : ERESTART;
1017 	}
1018 	CRYPTO_DRIVER_UNLOCK();
1019 
1020 	if (error) {
1021 		krp->krp_status = error;
1022 		crypto_kdone(krp);
1023 	}
1024 	return 0;
1025 }
1026 
1027 #ifdef CRYPTO_TIMING
1028 static void
1029 crypto_tstat(struct cryptotstat *ts, struct timespec *tv)
1030 {
1031 	struct timespec now, t;
1032 
1033 	nanouptime(&now);
1034 	t.tv_sec = now.tv_sec - tv->tv_sec;
1035 	t.tv_nsec = now.tv_nsec - tv->tv_nsec;
1036 	if (t.tv_nsec < 0) {
1037 		t.tv_sec--;
1038 		t.tv_nsec += 1000000000;
1039 	}
1040 	timespecadd(&ts->acc, &t);
1041 	if (timespeccmp(&t, &ts->min, <))
1042 		ts->min = t;
1043 	if (timespeccmp(&t, &ts->max, >))
1044 		ts->max = t;
1045 	ts->count++;
1046 
1047 	*tv = now;
1048 }
1049 #endif
1050 
1051 /*
1052  * Dispatch a crypto request to the appropriate crypto devices.
1053  */
1054 static int
1055 crypto_invoke(struct cryptocap *cap, struct cryptop *crp, int hint)
1056 {
1057 
1058 	KASSERT(crp != NULL, ("%s: crp == NULL", __func__));
1059 	KASSERT(crp->crp_callback != NULL,
1060 	    ("%s: crp->crp_callback == NULL", __func__));
1061 	KASSERT(crp->crp_desc != NULL, ("%s: crp->crp_desc == NULL", __func__));
1062 
1063 #ifdef CRYPTO_TIMING
1064 	if (crypto_timing)
1065 		crypto_tstat(&cryptostats.cs_invoke, &crp->crp_tstamp);
1066 #endif
1067 	if (cap->cc_flags & CRYPTOCAP_F_CLEANUP) {
1068 		struct cryptodesc *crd;
1069 		u_int64_t nid;
1070 
1071 		/*
1072 		 * Driver has unregistered; migrate the session and return
1073 		 * an error to the caller so they'll resubmit the op.
1074 		 *
1075 		 * XXX: What if there are more already queued requests for this
1076 		 *      session?
1077 		 */
1078 		crypto_freesession(crp->crp_sid);
1079 
1080 		for (crd = crp->crp_desc; crd->crd_next; crd = crd->crd_next)
1081 			crd->CRD_INI.cri_next = &(crd->crd_next->CRD_INI);
1082 
1083 		/* XXX propagate flags from initial session? */
1084 		if (crypto_newsession(&nid, &(crp->crp_desc->CRD_INI),
1085 		    CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE) == 0)
1086 			crp->crp_sid = nid;
1087 
1088 		crp->crp_etype = EAGAIN;
1089 		crypto_done(crp);
1090 		return 0;
1091 	} else {
1092 		/*
1093 		 * Invoke the driver to process the request.
1094 		 */
1095 		return CRYPTODEV_PROCESS(cap->cc_dev, crp, hint);
1096 	}
1097 }
1098 
1099 /*
1100  * Release a set of crypto descriptors.
1101  */
1102 void
1103 crypto_freereq(struct cryptop *crp)
1104 {
1105 	struct cryptodesc *crd;
1106 #ifdef DIAGNOSTIC
1107 	crypto_tdinfo_t tdinfo;
1108 	struct cryptop *crp2;
1109 	int n;
1110 #endif
1111 
1112 	if (crp == NULL)
1113 		return;
1114 
1115 #ifdef DIAGNOSTIC
1116 	for (n = 0; n < ncpus; ++n) {
1117 		tdinfo = &tdinfo_array[n];
1118 
1119 		CRYPTO_Q_LOCK(tdinfo);
1120 		TAILQ_FOREACH(crp2, &tdinfo->crp_q, crp_next) {
1121 			KASSERT(crp2 != crp,
1122 			    ("Freeing cryptop from the crypto queue (%p).",
1123 			    crp));
1124 		}
1125 		CRYPTO_Q_UNLOCK(tdinfo);
1126 	}
1127 	CRYPTO_RETQ_LOCK();
1128 	TAILQ_FOREACH(crp2, &crp_ret_q, crp_next) {
1129 		KASSERT(crp2 != crp,
1130 		    ("Freeing cryptop from the return queue (%p).",
1131 		    crp));
1132 	}
1133 	CRYPTO_RETQ_UNLOCK();
1134 #endif
1135 
1136 	while ((crd = crp->crp_desc) != NULL) {
1137 		crp->crp_desc = crd->crd_next;
1138 		zfree(cryptodesc_zone, crd);
1139 	}
1140 	zfree(cryptop_zone, crp);
1141 }
1142 
1143 /*
1144  * Acquire a set of crypto descriptors.
1145  */
1146 struct cryptop *
1147 crypto_getreq(int num)
1148 {
1149 	struct cryptodesc *crd;
1150 	struct cryptop *crp;
1151 
1152 	crp = zalloc(cryptop_zone);
1153 	if (crp != NULL) {
1154 		bzero(crp, sizeof (*crp));
1155 		while (num--) {
1156 			crd = zalloc(cryptodesc_zone);
1157 			if (crd == NULL) {
1158 				crypto_freereq(crp);
1159 				return NULL;
1160 			}
1161 			bzero(crd, sizeof (*crd));
1162 
1163 			crd->crd_next = crp->crp_desc;
1164 			crp->crp_desc = crd;
1165 		}
1166 	}
1167 	return crp;
1168 }
1169 
1170 /*
1171  * Invoke the callback on behalf of the driver.
1172  */
1173 void
1174 crypto_done(struct cryptop *crp)
1175 {
1176 	KASSERT((crp->crp_flags & CRYPTO_F_DONE) == 0,
1177 		("crypto_done: op already done, flags 0x%x", crp->crp_flags));
1178 	crp->crp_flags |= CRYPTO_F_DONE;
1179 	if (crp->crp_etype != 0)
1180 		cryptostats.cs_errs++;
1181 #ifdef CRYPTO_TIMING
1182 	if (crypto_timing)
1183 		crypto_tstat(&cryptostats.cs_done, &crp->crp_tstamp);
1184 #endif
1185 	/*
1186 	 * CBIMM means unconditionally do the callback immediately;
1187 	 * CBIFSYNC means do the callback immediately only if the
1188 	 * operation was done synchronously.  Both are used to avoid
1189 	 * doing extraneous context switches; the latter is mostly
1190 	 * used with the software crypto driver.
1191 	 */
1192 	if ((crp->crp_flags & CRYPTO_F_CBIMM) ||
1193 	    ((crp->crp_flags & CRYPTO_F_CBIFSYNC) &&
1194 	     (CRYPTO_SESID2CAPS(crp->crp_sid) & CRYPTOCAP_F_SYNC))) {
1195 		/*
1196 		 * Do the callback directly.  This is ok when the
1197 		 * callback routine does very little (e.g. the
1198 		 * /dev/crypto callback method just does a wakeup).
1199 		 */
1200 #ifdef CRYPTO_TIMING
1201 		if (crypto_timing) {
1202 			/*
1203 			 * NB: We must copy the timestamp before
1204 			 * doing the callback as the cryptop is
1205 			 * likely to be reclaimed.
1206 			 */
1207 			struct timespec t = crp->crp_tstamp;
1208 			crypto_tstat(&cryptostats.cs_cb, &t);
1209 			crp->crp_callback(crp);
1210 			crypto_tstat(&cryptostats.cs_finis, &t);
1211 		} else
1212 #endif
1213 			crp->crp_callback(crp);
1214 	} else {
1215 		/*
1216 		 * Normal case; queue the callback for the thread.
1217 		 */
1218 		CRYPTO_RETQ_LOCK();
1219 		if (CRYPTO_RETQ_EMPTY())
1220 			wakeup_one(&crp_ret_q);	/* shared wait channel */
1221 		TAILQ_INSERT_TAIL(&crp_ret_q, crp, crp_next);
1222 		CRYPTO_RETQ_UNLOCK();
1223 	}
1224 }
1225 
1226 /*
1227  * Invoke the callback on behalf of the driver.
1228  */
1229 void
1230 crypto_kdone(struct cryptkop *krp)
1231 {
1232 	struct cryptocap *cap;
1233 
1234 	if (krp->krp_status != 0)
1235 		cryptostats.cs_kerrs++;
1236 	CRYPTO_DRIVER_LOCK();
1237 	/* XXX: What if driver is loaded in the meantime? */
1238 	if (krp->krp_hid < crypto_drivers_num) {
1239 		cap = &crypto_drivers[krp->krp_hid];
1240 		cap->cc_koperations--;
1241 		KASSERT(cap->cc_koperations >= 0, ("cc_koperations < 0"));
1242 		if (cap->cc_flags & CRYPTOCAP_F_CLEANUP)
1243 			crypto_remove(cap);
1244 	}
1245 	CRYPTO_DRIVER_UNLOCK();
1246 	CRYPTO_RETQ_LOCK();
1247 	if (CRYPTO_RETQ_EMPTY())
1248 		wakeup_one(&crp_ret_q);		/* shared wait channel */
1249 	TAILQ_INSERT_TAIL(&crp_ret_kq, krp, krp_next);
1250 	CRYPTO_RETQ_UNLOCK();
1251 }
1252 
1253 int
1254 crypto_getfeat(int *featp)
1255 {
1256 	int hid, kalg, feat = 0;
1257 
1258 	CRYPTO_DRIVER_LOCK();
1259 	for (hid = 0; hid < crypto_drivers_num; hid++) {
1260 		const struct cryptocap *cap = &crypto_drivers[hid];
1261 
1262 		if ((cap->cc_flags & CRYPTOCAP_F_SOFTWARE) &&
1263 		    !crypto_devallowsoft) {
1264 			continue;
1265 		}
1266 		for (kalg = 0; kalg <= CRK_ALGORITHM_MAX; kalg++)
1267 			if (cap->cc_kalg[kalg] & CRYPTO_ALG_FLAG_SUPPORTED)
1268 				feat |=  1 << kalg;
1269 	}
1270 	CRYPTO_DRIVER_UNLOCK();
1271 	*featp = feat;
1272 	return (0);
1273 }
1274 
1275 /*
1276  * Terminate a thread at module unload.  The process that
1277  * initiated this is waiting for us to signal that we're gone;
1278  * wake it up and exit.  We use the driver table lock to insure
1279  * we don't do the wakeup before they're waiting.  There is no
1280  * race here because the waiter sleeps on the proc lock for the
1281  * thread so it gets notified at the right time because of an
1282  * extra wakeup that's done in exit1().
1283  */
1284 static void
1285 crypto_finis(void *chan)
1286 {
1287 	CRYPTO_DRIVER_LOCK();
1288 	wakeup_one(chan);
1289 	CRYPTO_DRIVER_UNLOCK();
1290 	kthread_exit();
1291 }
1292 
1293 /*
1294  * Crypto thread, dispatches crypto requests.
1295  */
1296 static void
1297 crypto_proc(void *arg)
1298 {
1299 	crypto_tdinfo_t tdinfo = arg;
1300 	struct cryptop *crp, *submit;
1301 	struct cryptkop *krp;
1302 	struct cryptocap *cap;
1303 	u_int32_t hid;
1304 	int result, hint;
1305 
1306 	rel_mplock();		/* release the mplock held on startup */
1307 
1308 	CRYPTO_Q_LOCK(tdinfo);
1309 
1310 	curthread->td_flags |= TDF_CRYPTO;
1311 
1312 	for (;;) {
1313 		/*
1314 		 * Find the first element in the queue that can be
1315 		 * processed and look-ahead to see if multiple ops
1316 		 * are ready for the same driver.
1317 		 */
1318 		submit = NULL;
1319 		hint = 0;
1320 		TAILQ_FOREACH(crp, &tdinfo->crp_q, crp_next) {
1321 			hid = CRYPTO_SESID2HID(crp->crp_sid);
1322 			cap = crypto_checkdriver(hid);
1323 			/*
1324 			 * Driver cannot disappeared when there is an active
1325 			 * session.
1326 			 */
1327 			KASSERT(cap != NULL, ("%s:%u Driver disappeared.",
1328 			    __func__, __LINE__));
1329 			if (cap == NULL || cap->cc_dev == NULL) {
1330 				/* Op needs to be migrated, process it. */
1331 				if (submit == NULL)
1332 					submit = crp;
1333 				break;
1334 			}
1335 			if (!cap->cc_qblocked) {
1336 				if (submit != NULL) {
1337 					/*
1338 					 * We stop on finding another op,
1339 					 * regardless whether its for the same
1340 					 * driver or not.  We could keep
1341 					 * searching the queue but it might be
1342 					 * better to just use a per-driver
1343 					 * queue instead.
1344 					 */
1345 					if (CRYPTO_SESID2HID(submit->crp_sid) == hid)
1346 						hint = CRYPTO_HINT_MORE;
1347 					break;
1348 				} else {
1349 					submit = crp;
1350 					if ((submit->crp_flags & CRYPTO_F_BATCH) == 0)
1351 						break;
1352 					/* keep scanning for more are q'd */
1353 				}
1354 			}
1355 		}
1356 		if (submit != NULL) {
1357 			TAILQ_REMOVE(&tdinfo->crp_q, submit, crp_next);
1358 			hid = CRYPTO_SESID2HID(submit->crp_sid);
1359 			cap = crypto_checkdriver(hid);
1360 			KASSERT(cap != NULL, ("%s:%u Driver disappeared.",
1361 			    __func__, __LINE__));
1362 
1363 			CRYPTO_Q_UNLOCK(tdinfo);
1364 			result = crypto_invoke(cap, submit, hint);
1365 			CRYPTO_Q_LOCK(tdinfo);
1366 
1367 			if (result == ERESTART) {
1368 				/*
1369 				 * The driver ran out of resources, mark the
1370 				 * driver ``blocked'' for cryptop's and put
1371 				 * the request back in the queue.  It would
1372 				 * best to put the request back where we got
1373 				 * it but that's hard so for now we put it
1374 				 * at the front.  This should be ok; putting
1375 				 * it at the end does not work.
1376 				 */
1377 				/* XXX validate sid again? */
1378 				crypto_drivers[CRYPTO_SESID2HID(submit->crp_sid)].cc_qblocked = 1;
1379 				TAILQ_INSERT_HEAD(&tdinfo->crp_q,
1380 						  submit, crp_next);
1381 				cryptostats.cs_blocks++;
1382 			}
1383 		}
1384 
1385 		/* As above, but for key ops */
1386 		TAILQ_FOREACH(krp, &tdinfo->crp_kq, krp_next) {
1387 			cap = crypto_checkdriver(krp->krp_hid);
1388 			if (cap == NULL || cap->cc_dev == NULL) {
1389 				/*
1390 				 * Operation needs to be migrated, invalidate
1391 				 * the assigned device so it will reselect a
1392 				 * new one below.  Propagate the original
1393 				 * crid selection flags if supplied.
1394 				 */
1395 				krp->krp_hid = krp->krp_crid &
1396 				    (CRYPTOCAP_F_SOFTWARE|CRYPTOCAP_F_HARDWARE);
1397 				if (krp->krp_hid == 0)
1398 					krp->krp_hid =
1399 				    CRYPTOCAP_F_SOFTWARE|CRYPTOCAP_F_HARDWARE;
1400 				break;
1401 			}
1402 			if (!cap->cc_kqblocked)
1403 				break;
1404 		}
1405 		if (krp != NULL) {
1406 			TAILQ_REMOVE(&tdinfo->crp_kq, krp, krp_next);
1407 
1408 			CRYPTO_Q_UNLOCK(tdinfo);
1409 			result = crypto_kinvoke(krp, krp->krp_hid);
1410 			CRYPTO_Q_LOCK(tdinfo);
1411 
1412 			if (result == ERESTART) {
1413 				/*
1414 				 * The driver ran out of resources, mark the
1415 				 * driver ``blocked'' for cryptkop's and put
1416 				 * the request back in the queue.  It would
1417 				 * best to put the request back where we got
1418 				 * it but that's hard so for now we put it
1419 				 * at the front.  This should be ok; putting
1420 				 * it at the end does not work.
1421 				 */
1422 				/* XXX validate sid again? */
1423 				crypto_drivers[krp->krp_hid].cc_kqblocked = 1;
1424 				TAILQ_INSERT_HEAD(&tdinfo->crp_kq,
1425 						  krp, krp_next);
1426 				cryptostats.cs_kblocks++;
1427 			}
1428 		}
1429 
1430 		if (submit == NULL && krp == NULL) {
1431 			/*
1432 			 * Nothing more to be processed.  Sleep until we're
1433 			 * woken because there are more ops to process.
1434 			 * This happens either by submission or by a driver
1435 			 * becoming unblocked and notifying us through
1436 			 * crypto_unblock.  Note that when we wakeup we
1437 			 * start processing each queue again from the
1438 			 * front. It's not clear that it's important to
1439 			 * preserve this ordering since ops may finish
1440 			 * out of order if dispatched to different devices
1441 			 * and some become blocked while others do not.
1442 			 */
1443 			tdinfo->crp_sleep = 1;
1444 			lksleep (&tdinfo->crp_q, &tdinfo->crp_lock,
1445 				 0, "crypto_wait", 0);
1446 			tdinfo->crp_sleep = 0;
1447 			if (tdinfo->crp_td == NULL)
1448 				break;
1449 			cryptostats.cs_intrs++;
1450 		}
1451 	}
1452 	CRYPTO_Q_UNLOCK(tdinfo);
1453 
1454 	crypto_finis(&tdinfo->crp_q);
1455 }
1456 
1457 /*
1458  * Crypto returns thread, does callbacks for processed crypto requests.
1459  * Callbacks are done here, rather than in the crypto drivers, because
1460  * callbacks typically are expensive and would slow interrupt handling.
1461  */
1462 static void
1463 crypto_ret_proc(void *dummy __unused)
1464 {
1465 	struct cryptop *crpt;
1466 	struct cryptkop *krpt;
1467 
1468 	CRYPTO_RETQ_LOCK();
1469 	for (;;) {
1470 		/* Harvest return q's for completed ops */
1471 		crpt = TAILQ_FIRST(&crp_ret_q);
1472 		if (crpt != NULL)
1473 			TAILQ_REMOVE(&crp_ret_q, crpt, crp_next);
1474 
1475 		krpt = TAILQ_FIRST(&crp_ret_kq);
1476 		if (krpt != NULL)
1477 			TAILQ_REMOVE(&crp_ret_kq, krpt, krp_next);
1478 
1479 		if (crpt != NULL || krpt != NULL) {
1480 			CRYPTO_RETQ_UNLOCK();
1481 			/*
1482 			 * Run callbacks unlocked.
1483 			 */
1484 			if (crpt != NULL) {
1485 #ifdef CRYPTO_TIMING
1486 				if (crypto_timing) {
1487 					/*
1488 					 * NB: We must copy the timestamp before
1489 					 * doing the callback as the cryptop is
1490 					 * likely to be reclaimed.
1491 					 */
1492 					struct timespec t = crpt->crp_tstamp;
1493 					crypto_tstat(&cryptostats.cs_cb, &t);
1494 					crpt->crp_callback(crpt);
1495 					crypto_tstat(&cryptostats.cs_finis, &t);
1496 				} else
1497 #endif
1498 					crpt->crp_callback(crpt);
1499 			}
1500 			if (krpt != NULL)
1501 				krpt->krp_callback(krpt);
1502 			CRYPTO_RETQ_LOCK();
1503 		} else {
1504 			/*
1505 			 * Nothing more to be processed.  Sleep until we're
1506 			 * woken because there are more returns to process.
1507 			 */
1508 			lksleep (&crp_ret_q, &crypto_ret_q_lock,
1509 				 0, "crypto_ret_wait", 0);
1510 			if (cryptoretthread == NULL)
1511 				break;
1512 			cryptostats.cs_rets++;
1513 		}
1514 	}
1515 	CRYPTO_RETQ_UNLOCK();
1516 
1517 	crypto_finis(&crp_ret_q);
1518 }
1519 
1520 #ifdef DDB
1521 static void
1522 db_show_drivers(void)
1523 {
1524 	int hid;
1525 
1526 	db_printf("%12s %4s %4s %8s %2s %2s\n"
1527 		, "Device"
1528 		, "Ses"
1529 		, "Kops"
1530 		, "Flags"
1531 		, "QB"
1532 		, "KB"
1533 	);
1534 	for (hid = 0; hid < crypto_drivers_num; hid++) {
1535 		const struct cryptocap *cap = &crypto_drivers[hid];
1536 		if (cap->cc_dev == NULL)
1537 			continue;
1538 		db_printf("%-12s %4u %4u %08x %2u %2u\n"
1539 		    , device_get_nameunit(cap->cc_dev)
1540 		    , cap->cc_sessions
1541 		    , cap->cc_koperations
1542 		    , cap->cc_flags
1543 		    , cap->cc_qblocked
1544 		    , cap->cc_kqblocked
1545 		);
1546 	}
1547 }
1548 
1549 DB_SHOW_COMMAND(crypto, db_show_crypto)
1550 {
1551 	crypto_tdinfo_t tdinfo;
1552 	struct cryptop *crp;
1553 	int n;
1554 
1555 	db_show_drivers();
1556 	db_printf("\n");
1557 
1558 	db_printf("%4s %8s %4s %4s %4s %4s %8s %8s\n",
1559 	    "HID", "Caps", "Ilen", "Olen", "Etype", "Flags",
1560 	    "Desc", "Callback");
1561 
1562 	for (n = 0; n < ncpus; ++n) {
1563 		tdinfo = &tdinfo_array[n];
1564 
1565 		TAILQ_FOREACH(crp, &tdinfo->crp_q, crp_next) {
1566 			db_printf("%4u %08x %4u %4u %4u %04x %8p %8p\n"
1567 			    , (int) CRYPTO_SESID2HID(crp->crp_sid)
1568 			    , (int) CRYPTO_SESID2CAPS(crp->crp_sid)
1569 			    , crp->crp_ilen, crp->crp_olen
1570 			    , crp->crp_etype
1571 			    , crp->crp_flags
1572 			    , crp->crp_desc
1573 			    , crp->crp_callback
1574 			);
1575 		}
1576 	}
1577 	if (!TAILQ_EMPTY(&crp_ret_q)) {
1578 		db_printf("\n%4s %4s %4s %8s\n",
1579 		    "HID", "Etype", "Flags", "Callback");
1580 		TAILQ_FOREACH(crp, &crp_ret_q, crp_next) {
1581 			db_printf("%4u %4u %04x %8p\n"
1582 			    , (int) CRYPTO_SESID2HID(crp->crp_sid)
1583 			    , crp->crp_etype
1584 			    , crp->crp_flags
1585 			    , crp->crp_callback
1586 			);
1587 		}
1588 	}
1589 }
1590 
1591 DB_SHOW_COMMAND(kcrypto, db_show_kcrypto)
1592 {
1593 	crypto_tdinfo_t tdinfo;
1594 	struct cryptkop *krp;
1595 	int n;
1596 
1597 	db_show_drivers();
1598 	db_printf("\n");
1599 
1600 	db_printf("%4s %5s %4s %4s %8s %4s %8s\n",
1601 	    "Op", "Status", "#IP", "#OP", "CRID", "HID", "Callback");
1602 
1603 	for (n = 0; n < ncpus; ++n) {
1604 		tdinfo = &tdinfo_array[n];
1605 
1606 		TAILQ_FOREACH(krp, &tdinfo->crp_kq, krp_next) {
1607 			db_printf("%4u %5u %4u %4u %08x %4u %8p\n"
1608 			    , krp->krp_op
1609 			    , krp->krp_status
1610 			    , krp->krp_iparams, krp->krp_oparams
1611 			    , krp->krp_crid, krp->krp_hid
1612 			    , krp->krp_callback
1613 			);
1614 		}
1615 	}
1616 	if (!TAILQ_EMPTY(&crp_ret_q)) {
1617 		db_printf("%4s %5s %8s %4s %8s\n",
1618 		    "Op", "Status", "CRID", "HID", "Callback");
1619 		TAILQ_FOREACH(krp, &crp_ret_kq, krp_next) {
1620 			db_printf("%4u %5u %08x %4u %8p\n"
1621 			    , krp->krp_op
1622 			    , krp->krp_status
1623 			    , krp->krp_crid, krp->krp_hid
1624 			    , krp->krp_callback
1625 			);
1626 		}
1627 	}
1628 }
1629 #endif
1630 
1631 int crypto_modevent(module_t mod, int type, void *unused);
1632 
1633 /*
1634  * Initialization code, both for static and dynamic loading.
1635  * Note this is not invoked with the usual MODULE_DECLARE
1636  * mechanism but instead is listed as a dependency by the
1637  * cryptosoft driver.  This guarantees proper ordering of
1638  * calls on module load/unload.
1639  */
1640 int
1641 crypto_modevent(module_t mod, int type, void *unused)
1642 {
1643 	int error = EINVAL;
1644 
1645 	switch (type) {
1646 	case MOD_LOAD:
1647 		error = crypto_init();
1648 		if (error == 0 && bootverbose)
1649 			kprintf("crypto: <crypto core>\n");
1650 		break;
1651 	case MOD_UNLOAD:
1652 		/*XXX disallow if active sessions */
1653 		error = 0;
1654 		crypto_destroy();
1655 		return 0;
1656 	}
1657 	return error;
1658 }
1659 MODULE_VERSION(crypto, 1);
1660 MODULE_DEPEND(crypto, zlib, 1, 1, 1);
1661