target/linux/generic/files/crypto/ocf/crypto.c

   1 /*-
   2  * Linux port done by David McCullough <david_mccullough@mcafee.com>
   3  * Copyright (C) 2006-2010 David McCullough
   4  * Copyright (C) 2004-2005 Intel Corporation.
   5  * The license and original author are listed below.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * Copyright (c) 2002-2006 Sam Leffler.  All rights reserved.
   9  *
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  */
  29
  30 #if 0
  31 #include <sys/cdefs.h>
  32 __FBSDID("$FreeBSD: src/sys/opencrypto/crypto.c,v 1.27 2007/03/21 03:42:51 sam Exp $");
  33 #endif
  34
  35 /*
  36  * Cryptographic Subsystem.
  37  *
  38  * This code is derived from the Openbsd Cryptographic Framework (OCF)
  39  * that has the copyright shown below.  Very little of the original
  40  * code remains.
  41  */
  42 /*-
  43  * The author of this code is Angelos D. Keromytis (angelos@cis.upenn.edu)
  44  *
  45  * This code was written by Angelos D. Keromytis in Athens, Greece, in
  46  * February 2000. Network Security Technologies Inc. (NSTI) kindly
  47  * supported the development of this code.
  48  *
  49  * Copyright (c) 2000, 2001 Angelos D. Keromytis
  50  *
  51  * Permission to use, copy, and modify this software with or without fee
  52  * is hereby granted, provided that this entire notice is included in
  53  * all source code copies of any software which is or includes a copy or
  54  * modification of this software.
  55  *
  56  * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
  57  * IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
  58  * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
  59  * MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
  60  * PURPOSE.
  61  *
  62 __FBSDID("$FreeBSD: src/sys/opencrypto/crypto.c,v 1.16 2005/01/07 02:29:16 imp Exp $");
  63  */
  64
  65
  66 #include <linux/version.h>
  67 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,38) && !defined(AUTOCONF_INCLUDED)
  68 #include <linux/config.h>
  69 #endif
  70 #include <linux/module.h>
  71 #include <linux/init.h>
  72 #include <linux/list.h>
  73 #include <linux/slab.h>
  74 #include <linux/wait.h>
  75 #include <linux/sched.h>
  76 #include <linux/spinlock.h>
  77 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,4)
  78 #include <linux/kthread.h>
  79 #endif
  80 #include <cryptodev.h>
  81
  82 /*
  83  * keep track of whether or not we have been initialised, a big
  84  * issue if we are linked into the kernel and a driver gets started before
  85  * us
  86  */
  87 static int crypto_initted = 0;
  88
  89 /*
  90  * Crypto drivers register themselves by allocating a slot in the
  91  * crypto_drivers table with crypto_get_driverid() and then registering
  92  * each algorithm they support with crypto_register() and crypto_kregister().
  93  */
  94
  95 /*
  96  * lock on driver table
  97  * we track its state as spin_is_locked does not do anything on non-SMP boxes
  98  */
  99 static spinlock_t       crypto_drivers_lock;
 100 static int                      crypto_drivers_locked;          /* for non-SMP boxes */
 101
 102 #define CRYPTO_DRIVER_LOCK() \
 103                         ({ \
 104                                 spin_lock_irqsave(&crypto_drivers_lock, d_flags); \
 105                                 crypto_drivers_locked = 1; \
 106                                 dprintk("%s,%d: DRIVER_LOCK()\n", __FILE__, __LINE__); \
 107                          })
 108 #define CRYPTO_DRIVER_UNLOCK() \
 109                         ({ \
 110                                 dprintk("%s,%d: DRIVER_UNLOCK()\n", __FILE__, __LINE__); \
 111                                 crypto_drivers_locked = 0; \
 112                                 spin_unlock_irqrestore(&crypto_drivers_lock, d_flags); \
 113                          })
 114 #define CRYPTO_DRIVER_ASSERT() \
 115                         ({ \
 116                                 if (!crypto_drivers_locked) { \
 117                                         dprintk("%s,%d: DRIVER_ASSERT!\n", __FILE__, __LINE__); \
 118                                 } \
 119                          })
 120
 121 /*
 122  * Crypto device/driver capabilities structure.
 123  *
 124  * Synchronization:
 125  * (d) - protected by CRYPTO_DRIVER_LOCK()
 126  * (q) - protected by CRYPTO_Q_LOCK()
 127  * Not tagged fields are read-only.
 128  */
 129 struct cryptocap {
 130         device_t        cc_dev;                 /* (d) device/driver */
 131         u_int32_t       cc_sessions;            /* (d) # of sessions */
 132         u_int32_t       cc_koperations;         /* (d) # os asym operations */
 133         /*
 134          * Largest possible operator length (in bits) for each type of
 135          * encryption algorithm. XXX not used
 136          */
 137         u_int16_t       cc_max_op_len[CRYPTO_ALGORITHM_MAX + 1];
 138         u_int8_t        cc_alg[CRYPTO_ALGORITHM_MAX + 1];
 139         u_int8_t        cc_kalg[CRK_ALGORITHM_MAX + 1];
 140
 141         int             cc_flags;               /* (d) flags */
 142 #define CRYPTOCAP_F_CLEANUP     0x80000000      /* needs resource cleanup */
 143         int             cc_qblocked;            /* (q) symmetric q blocked */
 144         int             cc_kqblocked;           /* (q) asymmetric q blocked */
 145
 146         int             cc_unqblocked;          /* (q) symmetric q blocked */
 147         int             cc_unkqblocked;         /* (q) asymmetric q blocked */
 148 };
 149 static struct cryptocap *crypto_drivers = NULL;
 150 static int crypto_drivers_num = 0;
 151
 152 /*
 153  * There are two queues for crypto requests; one for symmetric (e.g.
 154  * cipher) operations and one for asymmetric (e.g. MOD)operations.
 155  * A single mutex is used to lock access to both queues.  We could
 156  * have one per-queue but having one simplifies handling of block/unblock
 157  * operations.
 158  */
 159 static LIST_HEAD(crp_q);                /* crypto request queue */
 160 static LIST_HEAD(crp_kq);               /* asym request queue */
 161
 162 static spinlock_t crypto_q_lock;
 163
 164 int crypto_all_qblocked = 0;  /* protect with Q_LOCK */
 165 module_param(crypto_all_qblocked, int, 0444);
 166 MODULE_PARM_DESC(crypto_all_qblocked, "Are all crypto queues blocked");
 167
 168 int crypto_all_kqblocked = 0; /* protect with Q_LOCK */
 169 module_param(crypto_all_kqblocked, int, 0444);
 170 MODULE_PARM_DESC(crypto_all_kqblocked, "Are all asym crypto queues blocked");
 171
 172 #define CRYPTO_Q_LOCK() \
 173                         ({ \
 174                                 spin_lock_irqsave(&crypto_q_lock, q_flags); \
 175                                 dprintk("%s,%d: Q_LOCK()\n", __FILE__, __LINE__); \
 176                          })
 177 #define CRYPTO_Q_UNLOCK() \
 178                         ({ \
 179                                 dprintk("%s,%d: Q_UNLOCK()\n", __FILE__, __LINE__); \
 180                                 spin_unlock_irqrestore(&crypto_q_lock, q_flags); \
 181                          })
 182
 183 /*
 184  * There are two queues for processing completed crypto requests; one
 185  * for the symmetric and one for the asymmetric ops.  We only need one
 186  * but have two to avoid type futzing (cryptop vs. cryptkop).  A single
 187  * mutex is used to lock access to both queues.  Note that this lock
 188  * must be separate from the lock on request queues to insure driver
 189  * callbacks don't generate lock order reversals.
 190  */
 191 static LIST_HEAD(crp_ret_q);            /* callback queues */
 192 static LIST_HEAD(crp_ret_kq);
 193
 194 static spinlock_t crypto_ret_q_lock;
 195 #define CRYPTO_RETQ_LOCK() \
 196                         ({ \
 197                                 spin_lock_irqsave(&crypto_ret_q_lock, r_flags); \
 198                                 dprintk("%s,%d: RETQ_LOCK\n", __FILE__, __LINE__); \
 199                          })
 200 #define CRYPTO_RETQ_UNLOCK() \
 201                         ({ \
 202                                 dprintk("%s,%d: RETQ_UNLOCK\n", __FILE__, __LINE__); \
 203                                 spin_unlock_irqrestore(&crypto_ret_q_lock, r_flags); \
 204                          })
 205 #define CRYPTO_RETQ_EMPTY()     (list_empty(&crp_ret_q) && list_empty(&crp_ret_kq))
 206
 207 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,20)
 208 static kmem_cache_t *cryptop_zone;
 209 static kmem_cache_t *cryptodesc_zone;
 210 #else
 211 static struct kmem_cache *cryptop_zone;
 212 static struct kmem_cache *cryptodesc_zone;
 213 #endif
 214
 215 #define debug crypto_debug
 216 int crypto_debug = 0;
 217 module_param(crypto_debug, int, 0644);
 218 MODULE_PARM_DESC(crypto_debug, "Enable debug");
 219 EXPORT_SYMBOL(crypto_debug);
 220
 221 /*
 222  * Maximum number of outstanding crypto requests before we start
 223  * failing requests.  We need this to prevent DOS when too many
 224  * requests are arriving for us to keep up.  Otherwise we will
 225  * run the system out of memory.  Since crypto is slow,  we are
 226  * usually the bottleneck that needs to say, enough is enough.
 227  *
 228  * We cannot print errors when this condition occurs,  we are already too
 229  * slow,  printing anything will just kill us
 230  */
 231
 232 static int crypto_q_cnt = 0;
 233 module_param(crypto_q_cnt, int, 0444);
 234 MODULE_PARM_DESC(crypto_q_cnt,
 235                 "Current number of outstanding crypto requests");
 236
 237 static int crypto_q_max = 1000;
 238 module_param(crypto_q_max, int, 0644);
 239 MODULE_PARM_DESC(crypto_q_max,
 240                 "Maximum number of outstanding crypto requests");
 241
 242 #define bootverbose crypto_verbose
 243 static int crypto_verbose = 0;
 244 module_param(crypto_verbose, int, 0644);
 245 MODULE_PARM_DESC(crypto_verbose,
 246                 "Enable verbose crypto startup");
 247
 248 int     crypto_usercrypto = 1;  /* userland may do crypto reqs */
 249 module_param(crypto_usercrypto, int, 0644);
 250 MODULE_PARM_DESC(crypto_usercrypto,
 251            "Enable/disable user-mode access to crypto support");
 252
 253 int     crypto_userasymcrypto = 1;      /* userland may do asym crypto reqs */
 254 module_param(crypto_userasymcrypto, int, 0644);
 255 MODULE_PARM_DESC(crypto_userasymcrypto,
 256            "Enable/disable user-mode access to asymmetric crypto support");
 257
 258 int     crypto_devallowsoft = 0;        /* only use hardware crypto */
 259 module_param(crypto_devallowsoft, int, 0644);
 260 MODULE_PARM_DESC(crypto_devallowsoft,
 261            "Enable/disable use of software crypto support");
 262
 263 /*
 264  * This parameter controls the maximum number of crypto operations to
 265  * do consecutively in the crypto kernel thread before scheduling to allow
 266  * other processes to run. Without it, it is possible to get into a
 267  * situation where the crypto thread never allows any other processes to run.
 268  * Default to 1000 which should be less than one second.
 269  */
 270 static int crypto_max_loopcount = 1000;
 271 module_param(crypto_max_loopcount, int, 0644);
 272 MODULE_PARM_DESC(crypto_max_loopcount,
 273            "Maximum number of crypto ops to do before yielding to other processes");
 274
 275 #ifndef CONFIG_NR_CPUS
 276 #define CONFIG_NR_CPUS 1
 277 #endif
 278
 279 static struct task_struct *cryptoproc[CONFIG_NR_CPUS];
 280 static struct task_struct *cryptoretproc[CONFIG_NR_CPUS];
 281 static DECLARE_WAIT_QUEUE_HEAD(cryptoproc_wait);
 282 static DECLARE_WAIT_QUEUE_HEAD(cryptoretproc_wait);
 283
 284 static  int crypto_proc(void *arg);
 285 static  int crypto_ret_proc(void *arg);
 286 static  int crypto_invoke(struct cryptocap *cap, struct cryptop *crp, int hint);
 287 static  int crypto_kinvoke(struct cryptkop *krp, int flags);
 288 static  void crypto_exit(void);
 289 static  int crypto_init(void);
 290
 291 static  struct cryptostats cryptostats;
 292
 293 static struct cryptocap *
 294 crypto_checkdriver(u_int32_t hid)
 295 {
 296         if (crypto_drivers == NULL)
 297                 return NULL;
 298         return (hid >= crypto_drivers_num ? NULL : &crypto_drivers[hid]);
 299 }
 300
 301 /*
 302  * Compare a driver's list of supported algorithms against another
 303  * list; return non-zero if all algorithms are supported.
 304  */
 305 static int
 306 driver_suitable(const struct cryptocap *cap, const struct cryptoini *cri)
 307 {
 308         const struct cryptoini *cr;
 309
 310         /* See if all the algorithms are supported. */
 311         for (cr = cri; cr; cr = cr->cri_next)
 312                 if (cap->cc_alg[cr->cri_alg] == 0)
 313                         return 0;
 314         return 1;
 315 }
 316
 317
 318 /*
 319  * Select a driver for a new session that supports the specified
 320  * algorithms and, optionally, is constrained according to the flags.
 321  * The algorithm we use here is pretty stupid; just use the
 322  * first driver that supports all the algorithms we need. If there
 323  * are multiple drivers we choose the driver with the fewest active
 324  * sessions.  We prefer hardware-backed drivers to software ones.
 325  *
 326  * XXX We need more smarts here (in real life too, but that's
 327  * XXX another story altogether).
 328  */
 329 static struct cryptocap *
 330 crypto_select_driver(const struct cryptoini *cri, int flags)
 331 {
 332         struct cryptocap *cap, *best;
 333         int match, hid;
 334
 335         CRYPTO_DRIVER_ASSERT();
 336
 337         /*
 338          * Look first for hardware crypto devices if permitted.
 339          */
 340         if (flags & CRYPTOCAP_F_HARDWARE)
 341                 match = CRYPTOCAP_F_HARDWARE;
 342         else
 343                 match = CRYPTOCAP_F_SOFTWARE;
 344         best = NULL;
 345 again:
 346         for (hid = 0; hid < crypto_drivers_num; hid++) {
 347                 cap = &crypto_drivers[hid];
 348                 /*
 349                  * If it's not initialized, is in the process of
 350                  * going away, or is not appropriate (hardware
 351                  * or software based on match), then skip.
 352                  */
 353                 if (cap->cc_dev == NULL ||
 354                     (cap->cc_flags & CRYPTOCAP_F_CLEANUP) ||
 355                     (cap->cc_flags & match) == 0)
 356                         continue;
 357
 358                 /* verify all the algorithms are supported. */
 359                 if (driver_suitable(cap, cri)) {
 360                         if (best == NULL ||
 361                             cap->cc_sessions < best->cc_sessions)
 362                                 best = cap;
 363                 }
 364         }
 365         if (best != NULL)
 366                 return best;
 367         if (match == CRYPTOCAP_F_HARDWARE && (flags & CRYPTOCAP_F_SOFTWARE)) {
 368                 /* sort of an Algol 68-style for loop */
 369                 match = CRYPTOCAP_F_SOFTWARE;
 370                 goto again;
 371         }
 372         return best;
 373 }
 374
 375 /*
 376  * Create a new session.  The crid argument specifies a crypto
 377  * driver to use or constraints on a driver to select (hardware
 378  * only, software only, either).  Whatever driver is selected
 379  * must be capable of the requested crypto algorithms.
 380  */
 381 int
 382 crypto_newsession(u_int64_t *sid, struct cryptoini *cri, int crid)
 383 {
 384         struct cryptocap *cap;
 385         u_int32_t hid, lid;
 386         int err;
 387         unsigned long d_flags;
 388
 389         CRYPTO_DRIVER_LOCK();
 390         if ((crid & (CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE)) == 0) {
 391                 /*
 392                  * Use specified driver; verify it is capable.
 393                  */
 394                 cap = crypto_checkdriver(crid);
 395                 if (cap != NULL && !driver_suitable(cap, cri))
 396                         cap = NULL;
 397         } else {
 398                 /*
 399                  * No requested driver; select based on crid flags.
 400                  */
 401                 cap = crypto_select_driver(cri, crid);
 402                 /*
 403                  * if NULL then can't do everything in one session.
 404                  * XXX Fix this. We need to inject a "virtual" session
 405                  * XXX layer right about here.
 406                  */
 407         }
 408         if (cap != NULL) {
 409                 /* Call the driver initialization routine. */
 410                 hid = cap - crypto_drivers;
 411                 lid = hid;              /* Pass the driver ID. */
 412                 cap->cc_sessions++;
 413                 CRYPTO_DRIVER_UNLOCK();
 414                 err = CRYPTODEV_NEWSESSION(cap->cc_dev, &lid, cri);
 415                 CRYPTO_DRIVER_LOCK();
 416                 if (err == 0) {
 417                         (*sid) = (cap->cc_flags & 0xff000000)
 418                                | (hid & 0x00ffffff);
 419                         (*sid) <<= 32;
 420                         (*sid) |= (lid & 0xffffffff);
 421                 } else
 422                         cap->cc_sessions--;
 423         } else
 424                 err = EINVAL;
 425         CRYPTO_DRIVER_UNLOCK();
 426         return err;
 427 }
 428
 429 static void
 430 crypto_remove(struct cryptocap *cap)
 431 {
 432         CRYPTO_DRIVER_ASSERT();
 433         if (cap->cc_sessions == 0 && cap->cc_koperations == 0)
 434                 bzero(cap, sizeof(*cap));
 435 }
 436
 437 /*
 438  * Delete an existing session (or a reserved session on an unregistered
 439  * driver).
 440  */
 441 int
 442 crypto_freesession(u_int64_t sid)
 443 {
 444         struct cryptocap *cap;
 445         u_int32_t hid;
 446         int err = 0;
 447         unsigned long d_flags;
 448
 449         dprintk("%s()\n", __FUNCTION__);
 450         CRYPTO_DRIVER_LOCK();
 451
 452         if (crypto_drivers == NULL) {
 453                 err = EINVAL;
 454                 goto done;
 455         }
 456
 457         /* Determine two IDs. */
 458         hid = CRYPTO_SESID2HID(sid);
 459
 460         if (hid >= crypto_drivers_num) {
 461                 dprintk("%s - INVALID DRIVER NUM %d\n", __FUNCTION__, hid);
 462                 err = ENOENT;
 463                 goto done;
 464         }
 465         cap = &crypto_drivers[hid];
 466
 467         if (cap->cc_dev) {
 468                 CRYPTO_DRIVER_UNLOCK();
 469                 /* Call the driver cleanup routine, if available, unlocked. */
 470                 err = CRYPTODEV_FREESESSION(cap->cc_dev, sid);
 471                 CRYPTO_DRIVER_LOCK();
 472         }
 473
 474         if (cap->cc_sessions)
 475                 cap->cc_sessions--;
 476
 477         if (cap->cc_flags & CRYPTOCAP_F_CLEANUP)
 478                 crypto_remove(cap);
 479
 480 done:
 481         CRYPTO_DRIVER_UNLOCK();
 482         return err;
 483 }
 484
 485 /*
 486  * Return an unused driver id.  Used by drivers prior to registering
 487  * support for the algorithms they handle.
 488  */
 489 int32_t
 490 crypto_get_driverid(device_t dev, int flags)
 491 {
 492         struct cryptocap *newdrv;
 493         int i;
 494         unsigned long d_flags;
 495
 496         if ((flags & (CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE)) == 0) {
 497                 printf("%s: no flags specified when registering driver\n",
 498                     device_get_nameunit(dev));
 499                 return -1;
 500         }
 501
 502         CRYPTO_DRIVER_LOCK();
 503
 504         for (i = 0; i < crypto_drivers_num; i++) {
 505                 if (crypto_drivers[i].cc_dev == NULL &&
 506                     (crypto_drivers[i].cc_flags & CRYPTOCAP_F_CLEANUP) == 0) {
 507                         break;
 508                 }
 509         }
 510
 511         /* Out of entries, allocate some more. */
 512         if (i == crypto_drivers_num) {
 513                 /* Be careful about wrap-around. */
 514                 if (2 * crypto_drivers_num <= crypto_drivers_num) {
 515                         CRYPTO_DRIVER_UNLOCK();
 516                         printk("crypto: driver count wraparound!\n");
 517                         return -1;
 518                 }
 519
 520                 newdrv = kmalloc(2 * crypto_drivers_num * sizeof(struct cryptocap),
 521                                 GFP_KERNEL);
 522                 if (newdrv == NULL) {
 523                         CRYPTO_DRIVER_UNLOCK();
 524                         printk("crypto: no space to expand driver table!\n");
 525                         return -1;
 526                 }
 527
 528                 memcpy(newdrv, crypto_drivers,
 529                                 crypto_drivers_num * sizeof(struct cryptocap));
 530                 memset(&newdrv[crypto_drivers_num], 0,
 531                                 crypto_drivers_num * sizeof(struct cryptocap));
 532
 533                 crypto_drivers_num *= 2;
 534
 535                 kfree(crypto_drivers);
 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                 printf("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         unsigned long d_flags;
 563
 564         CRYPTO_DRIVER_LOCK();
 565         for (i = 0; i < crypto_drivers_num; i++) {
 566                 device_t dev = crypto_drivers[i].cc_dev;
 567                 if (dev == NULL ||
 568                     (crypto_drivers[i].cc_flags & CRYPTOCAP_F_CLEANUP))
 569                         continue;
 570                 if (strncmp(match, device_get_nameunit(dev), len) == 0 ||
 571                     strncmp(match, device_get_name(dev), len) == 0)
 572                         break;
 573         }
 574         CRYPTO_DRIVER_UNLOCK();
 575         return i < crypto_drivers_num ? i : -1;
 576 }
 577
 578 /*
 579  * Return the device_t for the specified driver or NULL
 580  * if the driver identifier is invalid.
 581  */
 582 device_t
 583 crypto_find_device_byhid(int hid)
 584 {
 585         struct cryptocap *cap = crypto_checkdriver(hid);
 586         return cap != NULL ? cap->cc_dev : NULL;
 587 }
 588
 589 /*
 590  * Return the device/driver capabilities.
 591  */
 592 int
 593 crypto_getcaps(int hid)
 594 {
 595         struct cryptocap *cap = crypto_checkdriver(hid);
 596         return cap != NULL ? cap->cc_flags : 0;
 597 }
 598
 599 /*
 600  * Register support for a key-related algorithm.  This routine
 601  * is called once for each algorithm supported a driver.
 602  */
 603 int
 604 crypto_kregister(u_int32_t driverid, int kalg, u_int32_t flags)
 605 {
 606         struct cryptocap *cap;
 607         int err;
 608         unsigned long d_flags;
 609
 610         dprintk("%s()\n", __FUNCTION__);
 611         CRYPTO_DRIVER_LOCK();
 612
 613         cap = crypto_checkdriver(driverid);
 614         if (cap != NULL &&
 615             (CRK_ALGORITM_MIN <= kalg && kalg <= CRK_ALGORITHM_MAX)) {
 616                 /*
 617                  * XXX Do some performance testing to determine placing.
 618                  * XXX We probably need an auxiliary data structure that
 619                  * XXX describes relative performances.
 620                  */
 621
 622                 cap->cc_kalg[kalg] = flags | CRYPTO_ALG_FLAG_SUPPORTED;
 623                 if (bootverbose)
 624                         printf("crypto: %s registers key alg %u flags %u\n"
 625                                 , device_get_nameunit(cap->cc_dev)
 626                                 , kalg
 627                                 , flags
 628                         );
 629                 err = 0;
 630         } else
 631                 err = EINVAL;
 632
 633         CRYPTO_DRIVER_UNLOCK();
 634         return err;
 635 }
 636
 637 /*
 638  * Register support for a non-key-related algorithm.  This routine
 639  * is called once for each such algorithm supported by a driver.
 640  */
 641 int
 642 crypto_register(u_int32_t driverid, int alg, u_int16_t maxoplen,
 643     u_int32_t flags)
 644 {
 645         struct cryptocap *cap;
 646         int err;
 647         unsigned long d_flags;
 648
 649         dprintk("%s(id=0x%x, alg=%d, maxoplen=%d, flags=0x%x)\n", __FUNCTION__,
 650                         driverid, alg, maxoplen, flags);
 651
 652         CRYPTO_DRIVER_LOCK();
 653
 654         cap = crypto_checkdriver(driverid);
 655         /* NB: algorithms are in the range [1..max] */
 656         if (cap != NULL &&
 657             (CRYPTO_ALGORITHM_MIN <= alg && alg <= CRYPTO_ALGORITHM_MAX)) {
 658                 /*
 659                  * XXX Do some performance testing to determine placing.
 660                  * XXX We probably need an auxiliary data structure that
 661                  * XXX describes relative performances.
 662                  */
 663
 664                 cap->cc_alg[alg] = flags | CRYPTO_ALG_FLAG_SUPPORTED;
 665                 cap->cc_max_op_len[alg] = maxoplen;
 666                 if (bootverbose)
 667                         printf("crypto: %s registers alg %u flags %u maxoplen %u\n"
 668                                 , device_get_nameunit(cap->cc_dev)
 669                                 , alg
 670                                 , flags
 671                                 , maxoplen
 672                         );
 673                 cap->cc_sessions = 0;           /* Unmark */
 674                 err = 0;
 675         } else
 676                 err = EINVAL;
 677
 678         CRYPTO_DRIVER_UNLOCK();
 679         return err;
 680 }
 681
 682 static void
 683 driver_finis(struct cryptocap *cap)
 684 {
 685         u_int32_t ses, kops;
 686
 687         CRYPTO_DRIVER_ASSERT();
 688
 689         ses = cap->cc_sessions;
 690         kops = cap->cc_koperations;
 691         bzero(cap, sizeof(*cap));
 692         if (ses != 0 || kops != 0) {
 693                 /*
 694                  * If there are pending sessions,
 695                  * just mark as invalid.
 696                  */
 697                 cap->cc_flags |= CRYPTOCAP_F_CLEANUP;
 698                 cap->cc_sessions = ses;
 699                 cap->cc_koperations = kops;
 700         }
 701 }
 702
 703 /*
 704  * Unregister a crypto driver. If there are pending sessions using it,
 705  * leave enough information around so that subsequent calls using those
 706  * sessions will correctly detect the driver has been unregistered and
 707  * reroute requests.
 708  */
 709 int
 710 crypto_unregister(u_int32_t driverid, int alg)
 711 {
 712         struct cryptocap *cap;
 713         int i, err;
 714         unsigned long d_flags;
 715
 716         dprintk("%s()\n", __FUNCTION__);
 717         CRYPTO_DRIVER_LOCK();
 718
 719         cap = crypto_checkdriver(driverid);
 720         if (cap != NULL &&
 721             (CRYPTO_ALGORITHM_MIN <= alg && alg <= CRYPTO_ALGORITHM_MAX) &&
 722             cap->cc_alg[alg] != 0) {
 723                 cap->cc_alg[alg] = 0;
 724                 cap->cc_max_op_len[alg] = 0;
 725
 726                 /* Was this the last algorithm ? */
 727                 for (i = 1; i <= CRYPTO_ALGORITHM_MAX; i++)
 728                         if (cap->cc_alg[i] != 0)
 729                                 break;
 730
 731                 if (i == CRYPTO_ALGORITHM_MAX + 1)
 732                         driver_finis(cap);
 733                 err = 0;
 734         } else
 735                 err = EINVAL;
 736         CRYPTO_DRIVER_UNLOCK();
 737         return err;
 738 }
 739
 740 /*
 741  * Unregister all algorithms associated with a crypto driver.
 742  * If there are pending sessions using it, leave enough information
 743  * around so that subsequent calls using those sessions will
 744  * correctly detect the driver has been unregistered and reroute
 745  * requests.
 746  */
 747 int
 748 crypto_unregister_all(u_int32_t driverid)
 749 {
 750         struct cryptocap *cap;
 751         int err;
 752         unsigned long d_flags;
 753
 754         dprintk("%s()\n", __FUNCTION__);
 755         CRYPTO_DRIVER_LOCK();
 756         cap = crypto_checkdriver(driverid);
 757         if (cap != NULL) {
 758                 driver_finis(cap);
 759                 err = 0;
 760         } else
 761                 err = EINVAL;
 762         CRYPTO_DRIVER_UNLOCK();
 763
 764         return err;
 765 }
 766
 767 /*
 768  * Clear blockage on a driver.  The what parameter indicates whether
 769  * the driver is now ready for cryptop's and/or cryptokop's.
 770  */
 771 int
 772 crypto_unblock(u_int32_t driverid, int what)
 773 {
 774         struct cryptocap *cap;
 775         int err;
 776         unsigned long q_flags;
 777
 778         CRYPTO_Q_LOCK();
 779         cap = crypto_checkdriver(driverid);
 780         if (cap != NULL) {
 781                 if (what & CRYPTO_SYMQ) {
 782                         cap->cc_qblocked = 0;
 783                         cap->cc_unqblocked = 0;
 784                         crypto_all_qblocked = 0;
 785                 }
 786                 if (what & CRYPTO_ASYMQ) {
 787                         cap->cc_kqblocked = 0;
 788                         cap->cc_unkqblocked = 0;
 789                         crypto_all_kqblocked = 0;
 790                 }
 791                 wake_up_interruptible(&cryptoproc_wait);
 792                 err = 0;
 793         } else
 794                 err = EINVAL;
 795         CRYPTO_Q_UNLOCK(); //DAVIDM should this be a driver lock
 796
 797         return err;
 798 }
 799
 800 /*
 801  * Add a crypto request to a queue, to be processed by the kernel thread.
 802  */
 803 int
 804 crypto_dispatch(struct cryptop *crp)
 805 {
 806         struct cryptocap *cap;
 807         int result = -1;
 808         unsigned long q_flags;
 809
 810         dprintk("%s()\n", __FUNCTION__);
 811
 812         cryptostats.cs_ops++;
 813
 814         CRYPTO_Q_LOCK();
 815         if (crypto_q_cnt >= crypto_q_max) {
 816                 cryptostats.cs_drops++;
 817                 CRYPTO_Q_UNLOCK();
 818                 return ENOMEM;
 819         }
 820         crypto_q_cnt++;
 821
 822         /* make sure we are starting a fresh run on this crp. */
 823         crp->crp_flags &= ~CRYPTO_F_DONE;
 824         crp->crp_etype = 0;
 825
 826         /*
 827          * Caller marked the request to be processed immediately; dispatch
 828          * it directly to the driver unless the driver is currently blocked.
 829          */
 830         if ((crp->crp_flags & CRYPTO_F_BATCH) == 0) {
 831                 int hid = CRYPTO_SESID2HID(crp->crp_sid);
 832                 cap = crypto_checkdriver(hid);
 833                 /* Driver cannot disappear when there is an active session. */
 834                 KASSERT(cap != NULL, ("%s: Driver disappeared.", __func__));
 835                 if (!cap->cc_qblocked) {
 836                         crypto_all_qblocked = 0;
 837                         crypto_drivers[hid].cc_unqblocked = 1;
 838                         CRYPTO_Q_UNLOCK();
 839                         result = crypto_invoke(cap, crp, 0);
 840                         CRYPTO_Q_LOCK();
 841                         if (result == ERESTART)
 842                                 if (crypto_drivers[hid].cc_unqblocked)
 843                                         crypto_drivers[hid].cc_qblocked = 1;
 844                         crypto_drivers[hid].cc_unqblocked = 0;
 845                 }
 846         }
 847         if (result == ERESTART) {
 848                 /*
 849                  * The driver ran out of resources, mark the
 850                  * driver ``blocked'' for cryptop's and put
 851                  * the request back in the queue.  It would
 852                  * best to put the request back where we got
 853                  * it but that's hard so for now we put it
 854                  * at the front.  This should be ok; putting
 855                  * it at the end does not work.
 856                  */
 857                 list_add(&crp->crp_next, &crp_q);
 858                 cryptostats.cs_blocks++;
 859                 result = 0;
 860         } else if (result == -1) {
 861                 TAILQ_INSERT_TAIL(&crp_q, crp, crp_next);
 862                 result = 0;
 863         }
 864         wake_up_interruptible(&cryptoproc_wait);
 865         CRYPTO_Q_UNLOCK();
 866         return result;
 867 }
 868
 869 /*
 870  * Add an asymetric crypto request to a queue,
 871  * to be processed by the kernel thread.
 872  */
 873 int
 874 crypto_kdispatch(struct cryptkop *krp)
 875 {
 876         int error;
 877         unsigned long q_flags;
 878
 879         cryptostats.cs_kops++;
 880
 881         error = crypto_kinvoke(krp, krp->krp_crid);
 882         if (error == ERESTART) {
 883                 CRYPTO_Q_LOCK();
 884                 TAILQ_INSERT_TAIL(&crp_kq, krp, krp_next);
 885                 wake_up_interruptible(&cryptoproc_wait);
 886                 CRYPTO_Q_UNLOCK();
 887                 error = 0;
 888         }
 889         return error;
 890 }
 891
 892 /*
 893  * Verify a driver is suitable for the specified operation.
 894  */
 895 static __inline int
 896 kdriver_suitable(const struct cryptocap *cap, const struct cryptkop *krp)
 897 {
 898         return (cap->cc_kalg[krp->krp_op] & CRYPTO_ALG_FLAG_SUPPORTED) != 0;
 899 }
 900
 901 /*
 902  * Select a driver for an asym operation.  The driver must
 903  * support the necessary algorithm.  The caller can constrain
 904  * which device is selected with the flags parameter.  The
 905  * algorithm we use here is pretty stupid; just use the first
 906  * driver that supports the algorithms we need. If there are
 907  * multiple suitable drivers we choose the driver with the
 908  * fewest active operations.  We prefer hardware-backed
 909  * drivers to software ones when either may be used.
 910  */
 911 static struct cryptocap *
 912 crypto_select_kdriver(const struct cryptkop *krp, int flags)
 913 {
 914         struct cryptocap *cap, *best, *blocked;
 915         int match, hid;
 916
 917         CRYPTO_DRIVER_ASSERT();
 918
 919         /*
 920          * Look first for hardware crypto devices if permitted.
 921          */
 922         if (flags & CRYPTOCAP_F_HARDWARE)
 923                 match = CRYPTOCAP_F_HARDWARE;
 924         else
 925                 match = CRYPTOCAP_F_SOFTWARE;
 926         best = NULL;
 927         blocked = NULL;
 928 again:
 929         for (hid = 0; hid < crypto_drivers_num; hid++) {
 930                 cap = &crypto_drivers[hid];
 931                 /*
 932                  * If it's not initialized, is in the process of
 933                  * going away, or is not appropriate (hardware
 934                  * or software based on match), then skip.
 935                  */
 936                 if (cap->cc_dev == NULL ||
 937                     (cap->cc_flags & CRYPTOCAP_F_CLEANUP) ||
 938                     (cap->cc_flags & match) == 0)
 939                         continue;
 940
 941                 /* verify all the algorithms are supported. */
 942                 if (kdriver_suitable(cap, krp)) {
 943                         if (best == NULL ||
 944                             cap->cc_koperations < best->cc_koperations)
 945                                 best = cap;
 946                 }
 947         }
 948         if (best != NULL)
 949                 return best;
 950         if (match == CRYPTOCAP_F_HARDWARE && (flags & CRYPTOCAP_F_SOFTWARE)) {
 951                 /* sort of an Algol 68-style for loop */
 952                 match = CRYPTOCAP_F_SOFTWARE;
 953                 goto again;
 954         }
 955         return best;
 956 }
 957
 958 /*
 959  * Dispatch an assymetric crypto request.
 960  */
 961 static int
 962 crypto_kinvoke(struct cryptkop *krp, int crid)
 963 {
 964         struct cryptocap *cap = NULL;
 965         int error;
 966         unsigned long d_flags;
 967
 968         KASSERT(krp != NULL, ("%s: krp == NULL", __func__));
 969         KASSERT(krp->krp_callback != NULL,
 970             ("%s: krp->crp_callback == NULL", __func__));
 971
 972         CRYPTO_DRIVER_LOCK();
 973         if ((crid & (CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE)) == 0) {
 974                 cap = crypto_checkdriver(crid);
 975                 if (cap != NULL) {
 976                         /*
 977                          * Driver present, it must support the necessary
 978                          * algorithm and, if s/w drivers are excluded,
 979                          * it must be registered as hardware-backed.
 980                          */
 981                         if (!kdriver_suitable(cap, krp) ||
 982                             (!crypto_devallowsoft &&
 983                              (cap->cc_flags & CRYPTOCAP_F_HARDWARE) == 0))
 984                                 cap = NULL;
 985                 }
 986         } else {
 987                 /*
 988                  * No requested driver; select based on crid flags.
 989                  */
 990                 if (!crypto_devallowsoft)       /* NB: disallow s/w drivers */
 991                         crid &= ~CRYPTOCAP_F_SOFTWARE;
 992                 cap = crypto_select_kdriver(krp, crid);
 993         }
 994         if (cap != NULL && !cap->cc_kqblocked) {
 995                 krp->krp_hid = cap - crypto_drivers;
 996                 cap->cc_koperations++;
 997                 CRYPTO_DRIVER_UNLOCK();
 998                 error = CRYPTODEV_KPROCESS(cap->cc_dev, krp, 0);
 999                 CRYPTO_DRIVER_LOCK();
1000                 if (error == ERESTART) {
1001                         cap->cc_koperations--;
1002                         CRYPTO_DRIVER_UNLOCK();
1003                         return (error);
1004                 }
1005                 /* return the actual device used */
1006                 krp->krp_crid = krp->krp_hid;
1007         } else {
1008                 /*
1009                  * NB: cap is !NULL if device is blocked; in
1010                  *     that case return ERESTART so the operation
1011                  *     is resubmitted if possible.
1012                  */
1013                 error = (cap == NULL) ? ENODEV : ERESTART;
1014         }
1015         CRYPTO_DRIVER_UNLOCK();
1016
1017         if (error) {
1018                 krp->krp_status = error;
1019                 crypto_kdone(krp);
1020         }
1021         return 0;
1022 }
1023
1024
1025 /*
1026  * Dispatch a crypto request to the appropriate crypto devices.
1027  */
1028 static int
1029 crypto_invoke(struct cryptocap *cap, struct cryptop *crp, int hint)
1030 {
1031         KASSERT(crp != NULL, ("%s: crp == NULL", __func__));
1032         KASSERT(crp->crp_callback != NULL,
1033             ("%s: crp->crp_callback == NULL", __func__));
1034         KASSERT(crp->crp_desc != NULL, ("%s: crp->crp_desc == NULL", __func__));
1035
1036         dprintk("%s()\n", __FUNCTION__);
1037
1038 #ifdef CRYPTO_TIMING
1039         if (crypto_timing)
1040                 crypto_tstat(&cryptostats.cs_invoke, &crp->crp_tstamp);
1041 #endif
1042         if (cap->cc_flags & CRYPTOCAP_F_CLEANUP) {
1043                 struct cryptodesc *crd;
1044                 u_int64_t nid;
1045
1046                 /*
1047                  * Driver has unregistered; migrate the session and return
1048                  * an error to the caller so they'll resubmit the op.
1049                  *
1050                  * XXX: What if there are more already queued requests for this
1051                  *      session?
1052                  */
1053                 crypto_freesession(crp->crp_sid);
1054
1055                 for (crd = crp->crp_desc; crd->crd_next; crd = crd->crd_next)
1056                         crd->CRD_INI.cri_next = &(crd->crd_next->CRD_INI);
1057
1058                 /* XXX propagate flags from initial session? */
1059                 if (crypto_newsession(&nid, &(crp->crp_desc->CRD_INI),
1060                     CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE) == 0)
1061                         crp->crp_sid = nid;
1062
1063                 crp->crp_etype = EAGAIN;
1064                 crypto_done(crp);
1065                 return 0;
1066         } else {
1067                 /*
1068                  * Invoke the driver to process the request.
1069                  */
1070                 return CRYPTODEV_PROCESS(cap->cc_dev, crp, hint);
1071         }
1072 }
1073
1074 /*
1075  * Release a set of crypto descriptors.
1076  */
1077 void
1078 crypto_freereq(struct cryptop *crp)
1079 {
1080         struct cryptodesc *crd;
1081
1082         if (crp == NULL)
1083                 return;
1084
1085 #ifdef DIAGNOSTIC
1086         {
1087                 struct cryptop *crp2;
1088                 unsigned long q_flags;
1089
1090                 CRYPTO_Q_LOCK();
1091                 TAILQ_FOREACH(crp2, &crp_q, crp_next) {
1092                         KASSERT(crp2 != crp,
1093                             ("Freeing cryptop from the crypto queue (%p).",
1094                             crp));
1095                 }
1096                 CRYPTO_Q_UNLOCK();
1097                 CRYPTO_RETQ_LOCK();
1098                 TAILQ_FOREACH(crp2, &crp_ret_q, crp_next) {
1099                         KASSERT(crp2 != crp,
1100                             ("Freeing cryptop from the return queue (%p).",
1101                             crp));
1102                 }
1103                 CRYPTO_RETQ_UNLOCK();
1104         }
1105 #endif
1106
1107         while ((crd = crp->crp_desc) != NULL) {
1108                 crp->crp_desc = crd->crd_next;
1109                 kmem_cache_free(cryptodesc_zone, crd);
1110         }
1111         kmem_cache_free(cryptop_zone, crp);
1112 }
1113
1114 /*
1115  * Acquire a set of crypto descriptors.
1116  */
1117 struct cryptop *
1118 crypto_getreq(int num)
1119 {
1120         struct cryptodesc *crd;
1121         struct cryptop *crp;
1122
1123         crp = kmem_cache_alloc(cryptop_zone, SLAB_ATOMIC);
1124         if (crp != NULL) {
1125                 memset(crp, 0, sizeof(*crp));
1126                 INIT_LIST_HEAD(&crp->crp_next);
1127                 init_waitqueue_head(&crp->crp_waitq);
1128                 while (num--) {
1129                         crd = kmem_cache_alloc(cryptodesc_zone, SLAB_ATOMIC);
1130                         if (crd == NULL) {
1131                                 crypto_freereq(crp);
1132                                 return NULL;
1133                         }
1134                         memset(crd, 0, sizeof(*crd));
1135                         crd->crd_next = crp->crp_desc;
1136                         crp->crp_desc = crd;
1137                 }
1138         }
1139         return crp;
1140 }
1141
1142 /*
1143  * Invoke the callback on behalf of the driver.
1144  */
1145 void
1146 crypto_done(struct cryptop *crp)
1147 {
1148         unsigned long q_flags;
1149
1150         dprintk("%s()\n", __FUNCTION__);
1151         if ((crp->crp_flags & CRYPTO_F_DONE) == 0) {
1152                 crp->crp_flags |= CRYPTO_F_DONE;
1153                 CRYPTO_Q_LOCK();
1154                 crypto_q_cnt--;
1155                 CRYPTO_Q_UNLOCK();
1156         } else
1157                 printk("crypto: crypto_done op already done, flags 0x%x",
1158                                 crp->crp_flags);
1159         if (crp->crp_etype != 0)
1160                 cryptostats.cs_errs++;
1161         /*
1162          * CBIMM means unconditionally do the callback immediately;
1163          * CBIFSYNC means do the callback immediately only if the
1164          * operation was done synchronously.  Both are used to avoid
1165          * doing extraneous context switches; the latter is mostly
1166          * used with the software crypto driver.
1167          */
1168         if ((crp->crp_flags & CRYPTO_F_CBIMM) ||
1169             ((crp->crp_flags & CRYPTO_F_CBIFSYNC) &&
1170              (CRYPTO_SESID2CAPS(crp->crp_sid) & CRYPTOCAP_F_SYNC))) {
1171                 /*
1172                  * Do the callback directly.  This is ok when the
1173                  * callback routine does very little (e.g. the
1174                  * /dev/crypto callback method just does a wakeup).
1175                  */
1176                 crp->crp_callback(crp);
1177         } else {
1178                 unsigned long r_flags;
1179                 /*
1180                  * Normal case; queue the callback for the thread.
1181                  */
1182                 CRYPTO_RETQ_LOCK();
1183                 wake_up_interruptible(&cryptoretproc_wait);/* shared wait channel */
1184                 TAILQ_INSERT_TAIL(&crp_ret_q, crp, crp_next);
1185                 CRYPTO_RETQ_UNLOCK();
1186         }
1187 }
1188
1189 /*
1190  * Invoke the callback on behalf of the driver.
1191  */
1192 void
1193 crypto_kdone(struct cryptkop *krp)
1194 {
1195         struct cryptocap *cap;
1196         unsigned long d_flags;
1197
1198         if ((krp->krp_flags & CRYPTO_KF_DONE) != 0)
1199                 printk("crypto: crypto_kdone op already done, flags 0x%x",
1200                                 krp->krp_flags);
1201         krp->krp_flags |= CRYPTO_KF_DONE;
1202         if (krp->krp_status != 0)
1203                 cryptostats.cs_kerrs++;
1204
1205         CRYPTO_DRIVER_LOCK();
1206         /* XXX: What if driver is loaded in the meantime? */
1207         if (krp->krp_hid < crypto_drivers_num) {
1208                 cap = &crypto_drivers[krp->krp_hid];
1209                 cap->cc_koperations--;
1210                 KASSERT(cap->cc_koperations >= 0, ("cc_koperations < 0"));
1211                 if (cap->cc_flags & CRYPTOCAP_F_CLEANUP)
1212                         crypto_remove(cap);
1213         }
1214         CRYPTO_DRIVER_UNLOCK();
1215
1216         /*
1217          * CBIMM means unconditionally do the callback immediately;
1218          * This is used to avoid doing extraneous context switches
1219          */
1220         if ((krp->krp_flags & CRYPTO_KF_CBIMM)) {
1221                 /*
1222                  * Do the callback directly.  This is ok when the
1223                  * callback routine does very little (e.g. the
1224                  * /dev/crypto callback method just does a wakeup).
1225                  */
1226                 krp->krp_callback(krp);
1227         } else {
1228                 unsigned long r_flags;
1229                 /*
1230                  * Normal case; queue the callback for the thread.
1231                  */
1232                 CRYPTO_RETQ_LOCK();
1233                 wake_up_interruptible(&cryptoretproc_wait);/* shared wait channel */
1234                 TAILQ_INSERT_TAIL(&crp_ret_kq, krp, krp_next);
1235                 CRYPTO_RETQ_UNLOCK();
1236         }
1237 }
1238
1239 int
1240 crypto_getfeat(int *featp)
1241 {
1242         int hid, kalg, feat = 0;
1243         unsigned long d_flags;
1244
1245         CRYPTO_DRIVER_LOCK();
1246         for (hid = 0; hid < crypto_drivers_num; hid++) {
1247                 const struct cryptocap *cap = &crypto_drivers[hid];
1248
1249                 if ((cap->cc_flags & CRYPTOCAP_F_SOFTWARE) &&
1250                     !crypto_devallowsoft) {
1251                         continue;
1252                 }
1253                 for (kalg = 0; kalg < CRK_ALGORITHM_MAX; kalg++)
1254                         if (cap->cc_kalg[kalg] & CRYPTO_ALG_FLAG_SUPPORTED)
1255                                 feat |=  1 << kalg;
1256         }
1257         CRYPTO_DRIVER_UNLOCK();
1258         *featp = feat;
1259         return (0);
1260 }
1261
1262 /*
1263  * Crypto thread, dispatches crypto requests.
1264  */
1265 static int
1266 crypto_proc(void *arg)
1267 {
1268         struct cryptop *crp, *submit;
1269         struct cryptkop *krp, *krpp;
1270         struct cryptocap *cap;
1271         u_int32_t hid;
1272         int result, hint;
1273         unsigned long q_flags;
1274         int loopcount = 0;
1275
1276         set_current_state(TASK_INTERRUPTIBLE);
1277
1278         CRYPTO_Q_LOCK();
1279         for (;;) {
1280                 /*
1281                  * we need to make sure we don't get into a busy loop with nothing
1282                  * to do,  the two crypto_all_*blocked vars help us find out when
1283                  * we are all full and can do nothing on any driver or Q.  If so we
1284                  * wait for an unblock.
1285                  */
1286                 crypto_all_qblocked  = !list_empty(&crp_q);
1287
1288                 /*
1289                  * Find the first element in the queue that can be
1290                  * processed and look-ahead to see if multiple ops
1291                  * are ready for the same driver.
1292                  */
1293                 submit = NULL;
1294                 hint = 0;
1295                 list_for_each_entry(crp, &crp_q, crp_next) {
1296                         hid = CRYPTO_SESID2HID(crp->crp_sid);
1297                         cap = crypto_checkdriver(hid);
1298                         /*
1299                          * Driver cannot disappear when there is an active
1300                          * session.
1301                          */
1302                         KASSERT(cap != NULL, ("%s:%u Driver disappeared.",
1303                             __func__, __LINE__));
1304                         if (cap == NULL || cap->cc_dev == NULL) {
1305                                 /* Op needs to be migrated, process it. */
1306                                 if (submit == NULL)
1307                                         submit = crp;
1308                                 break;
1309                         }
1310                         if (!cap->cc_qblocked) {
1311                                 if (submit != NULL) {
1312                                         /*
1313                                          * We stop on finding another op,
1314                                          * regardless whether its for the same
1315                                          * driver or not.  We could keep
1316                                          * searching the queue but it might be
1317                                          * better to just use a per-driver
1318                                          * queue instead.
1319                                          */
1320                                         if (CRYPTO_SESID2HID(submit->crp_sid) == hid)
1321                                                 hint = CRYPTO_HINT_MORE;
1322                                         break;
1323                                 } else {
1324                                         submit = crp;
1325                                         if ((submit->crp_flags & CRYPTO_F_BATCH) == 0)
1326                                                 break;
1327                                         /* keep scanning for more are q'd */
1328                                 }
1329                         }
1330                 }
1331                 if (submit != NULL) {
1332                         hid = CRYPTO_SESID2HID(submit->crp_sid);
1333                         crypto_all_qblocked = 0;
1334                         list_del(&submit->crp_next);
1335                         crypto_drivers[hid].cc_unqblocked = 1;
1336                         cap = crypto_checkdriver(hid);
1337                         CRYPTO_Q_UNLOCK();
1338                         KASSERT(cap != NULL, ("%s:%u Driver disappeared.",
1339                             __func__, __LINE__));
1340                         result = crypto_invoke(cap, submit, hint);
1341                         CRYPTO_Q_LOCK();
1342                         if (result == ERESTART) {
1343                                 /*
1344                                  * The driver ran out of resources, mark the
1345                                  * driver ``blocked'' for cryptop's and put
1346                                  * the request back in the queue.  It would
1347                                  * best to put the request back where we got
1348                                  * it but that's hard so for now we put it
1349                                  * at the front.  This should be ok; putting
1350                                  * it at the end does not work.
1351                                  */
1352                                 /* XXX validate sid again? */
1353                                 list_add(&submit->crp_next, &crp_q);
1354                                 cryptostats.cs_blocks++;
1355                                 if (crypto_drivers[hid].cc_unqblocked)
1356                                         crypto_drivers[hid].cc_qblocked=0;
1357                                 crypto_drivers[hid].cc_unqblocked=0;
1358                         }
1359                         crypto_drivers[hid].cc_unqblocked = 0;
1360                 }
1361
1362                 crypto_all_kqblocked = !list_empty(&crp_kq);
1363
1364                 /* As above, but for key ops */
1365                 krp = NULL;
1366                 list_for_each_entry(krpp, &crp_kq, krp_next) {
1367                         cap = crypto_checkdriver(krpp->krp_hid);
1368                         if (cap == NULL || cap->cc_dev == NULL) {
1369                                 /*
1370                                  * Operation needs to be migrated, invalidate
1371                                  * the assigned device so it will reselect a
1372                                  * new one below.  Propagate the original
1373                                  * crid selection flags if supplied.
1374                                  */
1375                                 krp->krp_hid = krp->krp_crid &
1376                                     (CRYPTOCAP_F_SOFTWARE|CRYPTOCAP_F_HARDWARE);
1377                                 if (krp->krp_hid == 0)
1378                                         krp->krp_hid =
1379                                     CRYPTOCAP_F_SOFTWARE|CRYPTOCAP_F_HARDWARE;
1380                                 break;
1381                         }
1382                         if (!cap->cc_kqblocked) {
1383                                 krp = krpp;
1384                                 break;
1385                         }
1386                 }
1387                 if (krp != NULL) {
1388                         crypto_all_kqblocked = 0;
1389                         list_del(&krp->krp_next);
1390                         crypto_drivers[krp->krp_hid].cc_kqblocked = 1;
1391                         CRYPTO_Q_UNLOCK();
1392                         result = crypto_kinvoke(krp, krp->krp_hid);
1393                         CRYPTO_Q_LOCK();
1394                         if (result == ERESTART) {
1395                                 /*
1396                                  * The driver ran out of resources, mark the
1397                                  * driver ``blocked'' for cryptkop's and put
1398                                  * the request back in the queue.  It would
1399                                  * best to put the request back where we got
1400                                  * it but that's hard so for now we put it
1401                                  * at the front.  This should be ok; putting
1402                                  * it at the end does not work.
1403                                  */
1404                                 /* XXX validate sid again? */
1405                                 list_add(&krp->krp_next, &crp_kq);
1406                                 cryptostats.cs_kblocks++;
1407                         } else
1408                                 crypto_drivers[krp->krp_hid].cc_kqblocked = 0;
1409                 }
1410
1411                 if (submit == NULL && krp == NULL) {
1412                         /*
1413                          * Nothing more to be processed.  Sleep until we're
1414                          * woken because there are more ops to process.
1415                          * This happens either by submission or by a driver
1416                          * becoming unblocked and notifying us through
1417                          * crypto_unblock.  Note that when we wakeup we
1418                          * start processing each queue again from the
1419                          * front. It's not clear that it's important to
1420                          * preserve this ordering since ops may finish
1421                          * out of order if dispatched to different devices
1422                          * and some become blocked while others do not.
1423                          */
1424                         dprintk("%s - sleeping (qe=%d qb=%d kqe=%d kqb=%d)\n",
1425                                         __FUNCTION__,
1426                                         list_empty(&crp_q), crypto_all_qblocked,
1427                                         list_empty(&crp_kq), crypto_all_kqblocked);
1428                         loopcount = 0;
1429                         CRYPTO_Q_UNLOCK();
1430                         wait_event_interruptible(cryptoproc_wait,
1431                                         !(list_empty(&crp_q) || crypto_all_qblocked) ||
1432                                         !(list_empty(&crp_kq) || crypto_all_kqblocked) ||
1433                                         kthread_should_stop());
1434                         if (signal_pending (current)) {
1435 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,0)
1436                                 spin_lock_irq(&current->sigmask_lock);
1437 #endif
1438                                 flush_signals(current);
1439 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,0)
1440                                 spin_unlock_irq(&current->sigmask_lock);
1441 #endif
1442                         }
1443                         CRYPTO_Q_LOCK();
1444                         dprintk("%s - awake\n", __FUNCTION__);
1445                         if (kthread_should_stop())
1446                                 break;
1447                         cryptostats.cs_intrs++;
1448                 } else if (loopcount > crypto_max_loopcount) {
1449                         /*
1450                          * Give other processes a chance to run if we've
1451                          * been using the CPU exclusively for a while.
1452                          */
1453                         loopcount = 0;
1454                         CRYPTO_Q_UNLOCK();
1455                         schedule();
1456                         CRYPTO_Q_LOCK();
1457                 }
1458                 loopcount++;
1459         }
1460         CRYPTO_Q_UNLOCK();
1461         return 0;
1462 }
1463
1464 /*
1465  * Crypto returns thread, does callbacks for processed crypto requests.
1466  * Callbacks are done here, rather than in the crypto drivers, because
1467  * callbacks typically are expensive and would slow interrupt handling.
1468  */
1469 static int
1470 crypto_ret_proc(void *arg)
1471 {
1472         struct cryptop *crpt;
1473         struct cryptkop *krpt;
1474         unsigned long  r_flags;
1475
1476         set_current_state(TASK_INTERRUPTIBLE);
1477
1478         CRYPTO_RETQ_LOCK();
1479         for (;;) {
1480                 /* Harvest return q's for completed ops */
1481                 crpt = NULL;
1482                 if (!list_empty(&crp_ret_q))
1483                         crpt = list_entry(crp_ret_q.next, typeof(*crpt), crp_next);
1484                 if (crpt != NULL)
1485                         list_del(&crpt->crp_next);
1486
1487                 krpt = NULL;
1488                 if (!list_empty(&crp_ret_kq))
1489                         krpt = list_entry(crp_ret_kq.next, typeof(*krpt), krp_next);
1490                 if (krpt != NULL)
1491                         list_del(&krpt->krp_next);
1492
1493                 if (crpt != NULL || krpt != NULL) {
1494                         CRYPTO_RETQ_UNLOCK();
1495                         /*
1496                          * Run callbacks unlocked.
1497                          */
1498                         if (crpt != NULL)
1499                                 crpt->crp_callback(crpt);
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                         dprintk("%s - sleeping\n", __FUNCTION__);
1509                         CRYPTO_RETQ_UNLOCK();
1510                         wait_event_interruptible(cryptoretproc_wait,
1511                                         !list_empty(&crp_ret_q) ||
1512                                         !list_empty(&crp_ret_kq) ||
1513                                         kthread_should_stop());
1514                         if (signal_pending (current)) {
1515 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,0)
1516                                 spin_lock_irq(&current->sigmask_lock);
1517 #endif
1518                                 flush_signals(current);
1519 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,0)
1520                                 spin_unlock_irq(&current->sigmask_lock);
1521 #endif
1522                         }
1523                         CRYPTO_RETQ_LOCK();
1524                         dprintk("%s - awake\n", __FUNCTION__);
1525                         if (kthread_should_stop()) {
1526                                 dprintk("%s - EXITING!\n", __FUNCTION__);
1527                                 break;
1528                         }
1529                         cryptostats.cs_rets++;
1530                 }
1531         }
1532         CRYPTO_RETQ_UNLOCK();
1533         return 0;
1534 }
1535
1536
1537 #if 0 /* should put this into /proc or something */
1538 static void
1539 db_show_drivers(void)
1540 {
1541         int hid;
1542
1543         db_printf("%12s %4s %4s %8s %2s %2s\n"
1544                 , "Device"
1545                 , "Ses"
1546                 , "Kops"
1547                 , "Flags"
1548                 , "QB"
1549                 , "KB"
1550         );
1551         for (hid = 0; hid < crypto_drivers_num; hid++) {
1552                 const struct cryptocap *cap = &crypto_drivers[hid];
1553                 if (cap->cc_dev == NULL)
1554                         continue;
1555                 db_printf("%-12s %4u %4u %08x %2u %2u\n"
1556                     , device_get_nameunit(cap->cc_dev)
1557                     , cap->cc_sessions
1558                     , cap->cc_koperations
1559                     , cap->cc_flags
1560                     , cap->cc_qblocked
1561                     , cap->cc_kqblocked
1562                 );
1563         }
1564 }
1565
1566 DB_SHOW_COMMAND(crypto, db_show_crypto)
1567 {
1568         struct cryptop *crp;
1569
1570         db_show_drivers();
1571         db_printf("\n");
1572
1573         db_printf("%4s %8s %4s %4s %4s %4s %8s %8s\n",
1574             "HID", "Caps", "Ilen", "Olen", "Etype", "Flags",
1575             "Desc", "Callback");
1576         TAILQ_FOREACH(crp, &crp_q, crp_next) {
1577                 db_printf("%4u %08x %4u %4u %4u %04x %8p %8p\n"
1578                     , (int) CRYPTO_SESID2HID(crp->crp_sid)
1579                     , (int) CRYPTO_SESID2CAPS(crp->crp_sid)
1580                     , crp->crp_ilen, crp->crp_olen
1581                     , crp->crp_etype
1582                     , crp->crp_flags
1583                     , crp->crp_desc
1584                     , crp->crp_callback
1585                 );
1586         }
1587         if (!TAILQ_EMPTY(&crp_ret_q)) {
1588                 db_printf("\n%4s %4s %4s %8s\n",
1589                     "HID", "Etype", "Flags", "Callback");
1590                 TAILQ_FOREACH(crp, &crp_ret_q, crp_next) {
1591                         db_printf("%4u %4u %04x %8p\n"
1592                             , (int) CRYPTO_SESID2HID(crp->crp_sid)
1593                             , crp->crp_etype
1594                             , crp->crp_flags
1595                             , crp->crp_callback
1596                         );
1597                 }
1598         }
1599 }
1600
1601 DB_SHOW_COMMAND(kcrypto, db_show_kcrypto)
1602 {
1603         struct cryptkop *krp;
1604
1605         db_show_drivers();
1606         db_printf("\n");
1607
1608         db_printf("%4s %5s %4s %4s %8s %4s %8s\n",
1609             "Op", "Status", "#IP", "#OP", "CRID", "HID", "Callback");
1610         TAILQ_FOREACH(krp, &crp_kq, krp_next) {
1611                 db_printf("%4u %5u %4u %4u %08x %4u %8p\n"
1612                     , krp->krp_op
1613                     , krp->krp_status
1614                     , krp->krp_iparams, krp->krp_oparams
1615                     , krp->krp_crid, krp->krp_hid
1616                     , krp->krp_callback
1617                 );
1618         }
1619         if (!TAILQ_EMPTY(&crp_ret_q)) {
1620                 db_printf("%4s %5s %8s %4s %8s\n",
1621                     "Op", "Status", "CRID", "HID", "Callback");
1622                 TAILQ_FOREACH(krp, &crp_ret_kq, krp_next) {
1623                         db_printf("%4u %5u %08x %4u %8p\n"
1624                             , krp->krp_op
1625                             , krp->krp_status
1626                             , krp->krp_crid, krp->krp_hid
1627                             , krp->krp_callback
1628                         );
1629                 }
1630         }
1631 }
1632 #endif
1633
1634
1635 static int
1636 crypto_init(void)
1637 {
1638         int error;
1639         unsigned long cpu;
1640
1641         dprintk("%s(%p)\n", __FUNCTION__, (void *) crypto_init);
1642
1643         if (crypto_initted)
1644                 return 0;
1645         crypto_initted = 1;
1646
1647         spin_lock_init(&crypto_drivers_lock);
1648         spin_lock_init(&crypto_q_lock);
1649         spin_lock_init(&crypto_ret_q_lock);
1650
1651         cryptop_zone = kmem_cache_create("cryptop", sizeof(struct cryptop),
1652                                        0, SLAB_HWCACHE_ALIGN, NULL
1653 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
1654                                        , NULL
1655 #endif
1656                                         );
1657
1658         cryptodesc_zone = kmem_cache_create("cryptodesc", sizeof(struct cryptodesc),
1659                                        0, SLAB_HWCACHE_ALIGN, NULL
1660 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
1661                                        , NULL
1662 #endif
1663                                         );
1664
1665         if (cryptodesc_zone == NULL || cryptop_zone == NULL) {
1666                 printk("crypto: crypto_init cannot setup crypto zones\n");
1667                 error = ENOMEM;
1668                 goto bad;
1669         }
1670
1671         crypto_drivers_num = CRYPTO_DRIVERS_INITIAL;
1672         crypto_drivers = kmalloc(crypto_drivers_num * sizeof(struct cryptocap),
1673                         GFP_KERNEL);
1674         if (crypto_drivers == NULL) {
1675                 printk("crypto: crypto_init cannot setup crypto drivers\n");
1676                 error = ENOMEM;
1677                 goto bad;
1678         }
1679
1680         memset(crypto_drivers, 0, crypto_drivers_num * sizeof(struct cryptocap));
1681
1682         ocf_for_each_cpu(cpu) {
1683                 cryptoproc[cpu] = kthread_create(crypto_proc, (void *) cpu,
1684                                                                         "ocf_%d", (int) cpu);
1685                 if (IS_ERR(cryptoproc[cpu])) {
1686                         error = PTR_ERR(cryptoproc[cpu]);
1687                         printk("crypto: crypto_init cannot start crypto thread; error %d",
1688                                 error);
1689                         goto bad;
1690                 }
1691                 kthread_bind(cryptoproc[cpu], cpu);
1692                 wake_up_process(cryptoproc[cpu]);
1693
1694                 cryptoretproc[cpu] = kthread_create(crypto_ret_proc, (void *) cpu,
1695                                                                         "ocf_ret_%d", (int) cpu);
1696                 if (IS_ERR(cryptoretproc[cpu])) {
1697                         error = PTR_ERR(cryptoretproc[cpu]);
1698                         printk("crypto: crypto_init cannot start cryptoret thread; error %d",
1699                                         error);
1700                         goto bad;
1701                 }
1702                 kthread_bind(cryptoretproc[cpu], cpu);
1703                 wake_up_process(cryptoretproc[cpu]);
1704         }
1705
1706         return 0;
1707 bad:
1708         crypto_exit();
1709         return error;
1710 }
1711
1712
1713 static void
1714 crypto_exit(void)
1715 {
1716         int cpu;
1717
1718         dprintk("%s()\n", __FUNCTION__);
1719
1720         /*
1721          * Terminate any crypto threads.
1722          */
1723         ocf_for_each_cpu(cpu) {
1724                 kthread_stop(cryptoproc[cpu]);
1725                 kthread_stop(cryptoretproc[cpu]);
1726         }
1727
1728         /*
1729          * Reclaim dynamically allocated resources.
1730          */
1731         if (crypto_drivers != NULL)
1732                 kfree(crypto_drivers);
1733
1734         if (cryptodesc_zone != NULL)
1735                 kmem_cache_destroy(cryptodesc_zone);
1736         if (cryptop_zone != NULL)
1737                 kmem_cache_destroy(cryptop_zone);
1738 }
1739
1740
1741 EXPORT_SYMBOL(crypto_newsession);
1742 EXPORT_SYMBOL(crypto_freesession);
1743 EXPORT_SYMBOL(crypto_get_driverid);
1744 EXPORT_SYMBOL(crypto_kregister);
1745 EXPORT_SYMBOL(crypto_register);
1746 EXPORT_SYMBOL(crypto_unregister);
1747 EXPORT_SYMBOL(crypto_unregister_all);
1748 EXPORT_SYMBOL(crypto_unblock);
1749 EXPORT_SYMBOL(crypto_dispatch);
1750 EXPORT_SYMBOL(crypto_kdispatch);
1751 EXPORT_SYMBOL(crypto_freereq);
1752 EXPORT_SYMBOL(crypto_getreq);
1753 EXPORT_SYMBOL(crypto_done);
1754 EXPORT_SYMBOL(crypto_kdone);
1755 EXPORT_SYMBOL(crypto_getfeat);
1756 EXPORT_SYMBOL(crypto_userasymcrypto);
1757 EXPORT_SYMBOL(crypto_getcaps);
1758 EXPORT_SYMBOL(crypto_find_driver);
1759 EXPORT_SYMBOL(crypto_find_device_byhid);
1760
1761 module_init(crypto_init);
1762 module_exit(crypto_exit);
1763
1764 MODULE_LICENSE("BSD");
1765 MODULE_AUTHOR("David McCullough <david_mccullough@mcafee.com>");
1766 MODULE_DESCRIPTION("OCF (OpenBSD Cryptographic Framework)");