engines/e_padlock.c

   1 /*
   2  * Copyright 2004-2018 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the OpenSSL license (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 #include <stdio.h>
  11 #include <string.h>
  12
  13 #include <openssl/opensslconf.h>
  14 #include <openssl/crypto.h>
  15 #include <openssl/engine.h>
  16 #include <openssl/evp.h>
  17 #include <openssl/aes.h>
  18 #include <openssl/rand.h>
  19 #include <openssl/err.h>
  20 #include <openssl/modes.h>
  21
  22 #ifndef OPENSSL_NO_HW
  23 # ifndef OPENSSL_NO_HW_PADLOCK
  24
  25 /*
  26  * VIA PadLock AES is available *ONLY* on some x86 CPUs. Not only that it
  27  * doesn't exist elsewhere, but it even can't be compiled on other platforms!
  28  */
  29
  30 #  undef COMPILE_HW_PADLOCK
  31 #  if !defined(I386_ONLY) && defined(PADLOCK_ASM)
  32 #   define COMPILE_HW_PADLOCK
  33 #   ifdef OPENSSL_NO_DYNAMIC_ENGINE
  34 static ENGINE *ENGINE_padlock(void);
  35 #   endif
  36 #  endif
  37
  38 #  ifdef OPENSSL_NO_DYNAMIC_ENGINE
  39 void engine_load_padlock_int(void);
  40 void engine_load_padlock_int(void)
  41 {
  42 /* On non-x86 CPUs it just returns. */
  43 #   ifdef COMPILE_HW_PADLOCK
  44     ENGINE *toadd = ENGINE_padlock();
  45     if (!toadd)
  46         return;
  47     ENGINE_add(toadd);
  48     ENGINE_free(toadd);
  49     ERR_clear_error();
  50 #   endif
  51 }
  52
  53 #  endif
  54
  55 #  ifdef COMPILE_HW_PADLOCK
  56
  57 /* Function for ENGINE detection and control */
  58 static int padlock_available(void);
  59 static int padlock_init(ENGINE *e);
  60
  61 /* RNG Stuff */
  62 static RAND_METHOD padlock_rand;
  63
  64 /* Cipher Stuff */
  65 static int padlock_ciphers(ENGINE *e, const EVP_CIPHER **cipher,
  66                            const int **nids, int nid);
  67
  68 /* Engine names */
  69 static const char *padlock_id = "padlock";
  70 static char padlock_name[100];
  71
  72 /* Available features */
  73 static int padlock_use_ace = 0; /* Advanced Cryptography Engine */
  74 static int padlock_use_rng = 0; /* Random Number Generator */
  75
  76 /* ===== Engine "management" functions ===== */
  77
  78 /* Prepare the ENGINE structure for registration */
  79 static int padlock_bind_helper(ENGINE *e)
  80 {
  81     /* Check available features */
  82     padlock_available();
  83
  84     /*
  85      * RNG is currently disabled for reasons discussed in commentary just
  86      * before padlock_rand_bytes function.
  87      */
  88     padlock_use_rng = 0;
  89
  90     /* Generate a nice engine name with available features */
  91     BIO_snprintf(padlock_name, sizeof(padlock_name),
  92                  "VIA PadLock (%s, %s)",
  93                  padlock_use_rng ? "RNG" : "no-RNG",
  94                  padlock_use_ace ? "ACE" : "no-ACE");
  95
  96     /* Register everything or return with an error */
  97     if (!ENGINE_set_id(e, padlock_id) ||
  98         !ENGINE_set_name(e, padlock_name) ||
  99         !ENGINE_set_init_function(e, padlock_init) ||
 100         (padlock_use_ace && !ENGINE_set_ciphers(e, padlock_ciphers)) ||
 101         (padlock_use_rng && !ENGINE_set_RAND(e, &padlock_rand))) {
 102         return 0;
 103     }
 104
 105     /* Everything looks good */
 106     return 1;
 107 }
 108
 109 #   ifdef OPENSSL_NO_DYNAMIC_ENGINE
 110 /* Constructor */
 111 static ENGINE *ENGINE_padlock(void)
 112 {
 113     ENGINE *eng = ENGINE_new();
 114
 115     if (eng == NULL) {
 116         return NULL;
 117     }
 118
 119     if (!padlock_bind_helper(eng)) {
 120         ENGINE_free(eng);
 121         return NULL;
 122     }
 123
 124     return eng;
 125 }
 126 #   endif
 127
 128 /* Check availability of the engine */
 129 static int padlock_init(ENGINE *e)
 130 {
 131     return (padlock_use_rng || padlock_use_ace);
 132 }
 133
 134 /*
 135  * This stuff is needed if this ENGINE is being compiled into a
 136  * self-contained shared-library.
 137  */
 138 #   ifdef DYNAMIC_ENGINE
 139 static int padlock_bind_fn(ENGINE *e, const char *id)
 140 {
 141     if (id && (strcmp(id, padlock_id) != 0)) {
 142         return 0;
 143     }
 144
 145     if (!padlock_bind_helper(e)) {
 146         return 0;
 147     }
 148
 149     return 1;
 150 }
 151
 152 IMPLEMENT_DYNAMIC_CHECK_FN()
 153 IMPLEMENT_DYNAMIC_BIND_FN(padlock_bind_fn)
 154 #   endif                       /* DYNAMIC_ENGINE */
 155 /* ===== Here comes the "real" engine ===== */
 156
 157 /* Some AES-related constants */
 158 #   define AES_BLOCK_SIZE          16
 159 #   define AES_KEY_SIZE_128        16
 160 #   define AES_KEY_SIZE_192        24
 161 #   define AES_KEY_SIZE_256        32
 162     /*
 163      * Here we store the status information relevant to the current context.
 164      */
 165     /*
 166      * BIG FAT WARNING: Inline assembler in PADLOCK_XCRYPT_ASM() depends on
 167      * the order of items in this structure.  Don't blindly modify, reorder,
 168      * etc!
 169      */
 170 struct padlock_cipher_data {
 171     unsigned char iv[AES_BLOCK_SIZE]; /* Initialization vector */
 172     union {
 173         unsigned int pad[4];
 174         struct {
 175             int rounds:4;
 176             int dgst:1;         /* n/a in C3 */
 177             int align:1;        /* n/a in C3 */
 178             int ciphr:1;        /* n/a in C3 */
 179             unsigned int keygen:1;
 180             int interm:1;
 181             unsigned int encdec:1;
 182             int ksize:2;
 183         } b;
 184     } cword;                    /* Control word */
 185     AES_KEY ks;                 /* Encryption key */
 186 };
 187
 188 /* Interface to assembler module */
 189 unsigned int padlock_capability(void);
 190 void padlock_key_bswap(AES_KEY *key);
 191 void padlock_verify_context(struct padlock_cipher_data *ctx);
 192 void padlock_reload_key(void);
 193 void padlock_aes_block(void *out, const void *inp,
 194                        struct padlock_cipher_data *ctx);
 195 int padlock_ecb_encrypt(void *out, const void *inp,
 196                         struct padlock_cipher_data *ctx, size_t len);
 197 int padlock_cbc_encrypt(void *out, const void *inp,
 198                         struct padlock_cipher_data *ctx, size_t len);
 199 int padlock_cfb_encrypt(void *out, const void *inp,
 200                         struct padlock_cipher_data *ctx, size_t len);
 201 int padlock_ofb_encrypt(void *out, const void *inp,
 202                         struct padlock_cipher_data *ctx, size_t len);
 203 int padlock_ctr32_encrypt(void *out, const void *inp,
 204                           struct padlock_cipher_data *ctx, size_t len);
 205 int padlock_xstore(void *out, int edx);
 206 void padlock_sha1_oneshot(void *ctx, const void *inp, size_t len);
 207 void padlock_sha1(void *ctx, const void *inp, size_t len);
 208 void padlock_sha256_oneshot(void *ctx, const void *inp, size_t len);
 209 void padlock_sha256(void *ctx, const void *inp, size_t len);
 210
 211 /*
 212  * Load supported features of the CPU to see if the PadLock is available.
 213  */
 214 static int padlock_available(void)
 215 {
 216     unsigned int edx = padlock_capability();
 217
 218     /* Fill up some flags */
 219     padlock_use_ace = ((edx & (0x3 << 6)) == (0x3 << 6));
 220     padlock_use_rng = ((edx & (0x3 << 2)) == (0x3 << 2));
 221
 222     return padlock_use_ace + padlock_use_rng;
 223 }
 224
 225 /* ===== AES encryption/decryption ===== */
 226
 227 #   if defined(NID_aes_128_cfb128) && ! defined (NID_aes_128_cfb)
 228 #    define NID_aes_128_cfb NID_aes_128_cfb128
 229 #   endif
 230
 231 #   if defined(NID_aes_128_ofb128) && ! defined (NID_aes_128_ofb)
 232 #    define NID_aes_128_ofb NID_aes_128_ofb128
 233 #   endif
 234
 235 #   if defined(NID_aes_192_cfb128) && ! defined (NID_aes_192_cfb)
 236 #    define NID_aes_192_cfb NID_aes_192_cfb128
 237 #   endif
 238
 239 #   if defined(NID_aes_192_ofb128) && ! defined (NID_aes_192_ofb)
 240 #    define NID_aes_192_ofb NID_aes_192_ofb128
 241 #   endif
 242
 243 #   if defined(NID_aes_256_cfb128) && ! defined (NID_aes_256_cfb)
 244 #    define NID_aes_256_cfb NID_aes_256_cfb128
 245 #   endif
 246
 247 #   if defined(NID_aes_256_ofb128) && ! defined (NID_aes_256_ofb)
 248 #    define NID_aes_256_ofb NID_aes_256_ofb128
 249 #   endif
 250
 251 /* List of supported ciphers. */
 252 static const int padlock_cipher_nids[] = {
 253     NID_aes_128_ecb,
 254     NID_aes_128_cbc,
 255     NID_aes_128_cfb,
 256     NID_aes_128_ofb,
 257     NID_aes_128_ctr,
 258
 259     NID_aes_192_ecb,
 260     NID_aes_192_cbc,
 261     NID_aes_192_cfb,
 262     NID_aes_192_ofb,
 263     NID_aes_192_ctr,
 264
 265     NID_aes_256_ecb,
 266     NID_aes_256_cbc,
 267     NID_aes_256_cfb,
 268     NID_aes_256_ofb,
 269     NID_aes_256_ctr
 270 };
 271
 272 static int padlock_cipher_nids_num = (sizeof(padlock_cipher_nids) /
 273                                       sizeof(padlock_cipher_nids[0]));
 274
 275 /* Function prototypes ... */
 276 static int padlock_aes_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,
 277                                 const unsigned char *iv, int enc);
 278
 279 #   define NEAREST_ALIGNED(ptr) ( (unsigned char *)(ptr) +         \
 280         ( (0x10 - ((size_t)(ptr) & 0x0F)) & 0x0F )      )
 281 #   define ALIGNED_CIPHER_DATA(ctx) ((struct padlock_cipher_data *)\
 282         NEAREST_ALIGNED(EVP_CIPHER_CTX_get_cipher_data(ctx)))
 283
 284 static int
 285 padlock_ecb_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
 286                    const unsigned char *in_arg, size_t nbytes)
 287 {
 288     return padlock_ecb_encrypt(out_arg, in_arg,
 289                                ALIGNED_CIPHER_DATA(ctx), nbytes);
 290 }
 291
 292 static int
 293 padlock_cbc_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
 294                    const unsigned char *in_arg, size_t nbytes)
 295 {
 296     struct padlock_cipher_data *cdata = ALIGNED_CIPHER_DATA(ctx);
 297     int ret;
 298
 299     memcpy(cdata->iv, EVP_CIPHER_CTX_iv(ctx), AES_BLOCK_SIZE);
 300     if ((ret = padlock_cbc_encrypt(out_arg, in_arg, cdata, nbytes)))
 301         memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), cdata->iv, AES_BLOCK_SIZE);
 302     return ret;
 303 }
 304
 305 static int
 306 padlock_cfb_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
 307                    const unsigned char *in_arg, size_t nbytes)
 308 {
 309     struct padlock_cipher_data *cdata = ALIGNED_CIPHER_DATA(ctx);
 310     size_t chunk;
 311
 312     if ((chunk = EVP_CIPHER_CTX_num(ctx))) {   /* borrow chunk variable */
 313         unsigned char *ivp = EVP_CIPHER_CTX_iv_noconst(ctx);
 314
 315         if (chunk >= AES_BLOCK_SIZE)
 316             return 0;           /* bogus value */
 317
 318         if (EVP_CIPHER_CTX_encrypting(ctx))
 319             while (chunk < AES_BLOCK_SIZE && nbytes != 0) {
 320                 ivp[chunk] = *(out_arg++) = *(in_arg++) ^ ivp[chunk];
 321                 chunk++, nbytes--;
 322         } else
 323             while (chunk < AES_BLOCK_SIZE && nbytes != 0) {
 324                 unsigned char c = *(in_arg++);
 325                 *(out_arg++) = c ^ ivp[chunk];
 326                 ivp[chunk++] = c, nbytes--;
 327             }
 328
 329         EVP_CIPHER_CTX_set_num(ctx, chunk % AES_BLOCK_SIZE);
 330     }
 331
 332     if (nbytes == 0)
 333         return 1;
 334
 335     memcpy(cdata->iv, EVP_CIPHER_CTX_iv(ctx), AES_BLOCK_SIZE);
 336
 337     if ((chunk = nbytes & ~(AES_BLOCK_SIZE - 1))) {
 338         if (!padlock_cfb_encrypt(out_arg, in_arg, cdata, chunk))
 339             return 0;
 340         nbytes -= chunk;
 341     }
 342
 343     if (nbytes) {
 344         unsigned char *ivp = cdata->iv;
 345
 346         out_arg += chunk;
 347         in_arg += chunk;
 348         EVP_CIPHER_CTX_set_num(ctx, nbytes);
 349         if (cdata->cword.b.encdec) {
 350             cdata->cword.b.encdec = 0;
 351             padlock_reload_key();
 352             padlock_aes_block(ivp, ivp, cdata);
 353             cdata->cword.b.encdec = 1;
 354             padlock_reload_key();
 355             while (nbytes) {
 356                 unsigned char c = *(in_arg++);
 357                 *(out_arg++) = c ^ *ivp;
 358                 *(ivp++) = c, nbytes--;
 359             }
 360         } else {
 361             padlock_reload_key();
 362             padlock_aes_block(ivp, ivp, cdata);
 363             padlock_reload_key();
 364             while (nbytes) {
 365                 *ivp = *(out_arg++) = *(in_arg++) ^ *ivp;
 366                 ivp++, nbytes--;
 367             }
 368         }
 369     }
 370
 371     memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), cdata->iv, AES_BLOCK_SIZE);
 372
 373     return 1;
 374 }
 375
 376 static int
 377 padlock_ofb_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
 378                    const unsigned char *in_arg, size_t nbytes)
 379 {
 380     struct padlock_cipher_data *cdata = ALIGNED_CIPHER_DATA(ctx);
 381     size_t chunk;
 382
 383     /*
 384      * ctx->num is maintained in byte-oriented modes, such as CFB and OFB...
 385      */
 386     if ((chunk = EVP_CIPHER_CTX_num(ctx))) {   /* borrow chunk variable */
 387         unsigned char *ivp = EVP_CIPHER_CTX_iv_noconst(ctx);
 388
 389         if (chunk >= AES_BLOCK_SIZE)
 390             return 0;           /* bogus value */
 391
 392         while (chunk < AES_BLOCK_SIZE && nbytes != 0) {
 393             *(out_arg++) = *(in_arg++) ^ ivp[chunk];
 394             chunk++, nbytes--;
 395         }
 396
 397         EVP_CIPHER_CTX_set_num(ctx, chunk % AES_BLOCK_SIZE);
 398     }
 399
 400     if (nbytes == 0)
 401         return 1;
 402
 403     memcpy(cdata->iv, EVP_CIPHER_CTX_iv(ctx), AES_BLOCK_SIZE);
 404
 405     if ((chunk = nbytes & ~(AES_BLOCK_SIZE - 1))) {
 406         if (!padlock_ofb_encrypt(out_arg, in_arg, cdata, chunk))
 407             return 0;
 408         nbytes -= chunk;
 409     }
 410
 411     if (nbytes) {
 412         unsigned char *ivp = cdata->iv;
 413
 414         out_arg += chunk;
 415         in_arg += chunk;
 416         EVP_CIPHER_CTX_set_num(ctx, nbytes);
 417         padlock_reload_key();   /* empirically found */
 418         padlock_aes_block(ivp, ivp, cdata);
 419         padlock_reload_key();   /* empirically found */
 420         while (nbytes) {
 421             *(out_arg++) = *(in_arg++) ^ *ivp;
 422             ivp++, nbytes--;
 423         }
 424     }
 425
 426     memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), cdata->iv, AES_BLOCK_SIZE);
 427
 428     return 1;
 429 }
 430
 431 static void padlock_ctr32_encrypt_glue(const unsigned char *in,
 432                                        unsigned char *out, size_t blocks,
 433                                        struct padlock_cipher_data *ctx,
 434                                        const unsigned char *ivec)
 435 {
 436     memcpy(ctx->iv, ivec, AES_BLOCK_SIZE);
 437     padlock_ctr32_encrypt(out, in, ctx, AES_BLOCK_SIZE * blocks);
 438 }
 439
 440 static int
 441 padlock_ctr_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
 442                    const unsigned char *in_arg, size_t nbytes)
 443 {
 444     struct padlock_cipher_data *cdata = ALIGNED_CIPHER_DATA(ctx);
 445     unsigned int num = EVP_CIPHER_CTX_num(ctx);
 446
 447     CRYPTO_ctr128_encrypt_ctr32(in_arg, out_arg, nbytes,
 448                                 cdata, EVP_CIPHER_CTX_iv_noconst(ctx),
 449                                 EVP_CIPHER_CTX_buf_noconst(ctx), &num,
 450                                 (ctr128_f) padlock_ctr32_encrypt_glue);
 451
 452     EVP_CIPHER_CTX_set_num(ctx, (size_t)num);
 453     return 1;
 454 }
 455
 456 #   define EVP_CIPHER_block_size_ECB       AES_BLOCK_SIZE
 457 #   define EVP_CIPHER_block_size_CBC       AES_BLOCK_SIZE
 458 #   define EVP_CIPHER_block_size_OFB       1
 459 #   define EVP_CIPHER_block_size_CFB       1
 460 #   define EVP_CIPHER_block_size_CTR       1
 461
 462 /*
 463  * Declaring so many ciphers by hand would be a pain. Instead introduce a bit
 464  * of preprocessor magic :-)
 465  */
 466 #   define DECLARE_AES_EVP(ksize,lmode,umode)      \
 467 static EVP_CIPHER *_hidden_aes_##ksize##_##lmode = NULL; \
 468 static const EVP_CIPHER *padlock_aes_##ksize##_##lmode(void) \
 469 {                                                                       \
 470     if (_hidden_aes_##ksize##_##lmode == NULL                           \
 471         && ((_hidden_aes_##ksize##_##lmode =                            \
 472              EVP_CIPHER_meth_new(NID_aes_##ksize##_##lmode,             \
 473                                  EVP_CIPHER_block_size_##umode,         \
 474                                  AES_KEY_SIZE_##ksize)) == NULL         \
 475             || !EVP_CIPHER_meth_set_iv_length(_hidden_aes_##ksize##_##lmode, \
 476                                               AES_BLOCK_SIZE)           \
 477             || !EVP_CIPHER_meth_set_flags(_hidden_aes_##ksize##_##lmode, \
 478                                           0 | EVP_CIPH_##umode##_MODE)  \
 479             || !EVP_CIPHER_meth_set_init(_hidden_aes_##ksize##_##lmode, \
 480                                          padlock_aes_init_key)          \
 481             || !EVP_CIPHER_meth_set_do_cipher(_hidden_aes_##ksize##_##lmode, \
 482                                               padlock_##lmode##_cipher) \
 483             || !EVP_CIPHER_meth_set_impl_ctx_size(_hidden_aes_##ksize##_##lmode, \
 484                                                   sizeof(struct padlock_cipher_data) + 16) \
 485             || !EVP_CIPHER_meth_set_set_asn1_params(_hidden_aes_##ksize##_##lmode, \
 486                                                     EVP_CIPHER_set_asn1_iv) \
 487             || !EVP_CIPHER_meth_set_get_asn1_params(_hidden_aes_##ksize##_##lmode, \
 488                                                     EVP_CIPHER_get_asn1_iv))) { \
 489         EVP_CIPHER_meth_free(_hidden_aes_##ksize##_##lmode);            \
 490         _hidden_aes_##ksize##_##lmode = NULL;                           \
 491     }                                                                   \
 492     return _hidden_aes_##ksize##_##lmode;                               \
 493 }
 494
 495 DECLARE_AES_EVP(128, ecb, ECB)
 496 DECLARE_AES_EVP(128, cbc, CBC)
 497 DECLARE_AES_EVP(128, cfb, CFB)
 498 DECLARE_AES_EVP(128, ofb, OFB)
 499 DECLARE_AES_EVP(128, ctr, CTR)
 500
 501 DECLARE_AES_EVP(192, ecb, ECB)
 502 DECLARE_AES_EVP(192, cbc, CBC)
 503 DECLARE_AES_EVP(192, cfb, CFB)
 504 DECLARE_AES_EVP(192, ofb, OFB)
 505 DECLARE_AES_EVP(192, ctr, CTR)
 506
 507 DECLARE_AES_EVP(256, ecb, ECB)
 508 DECLARE_AES_EVP(256, cbc, CBC)
 509 DECLARE_AES_EVP(256, cfb, CFB)
 510 DECLARE_AES_EVP(256, ofb, OFB)
 511 DECLARE_AES_EVP(256, ctr, CTR)
 512
 513 static int
 514 padlock_ciphers(ENGINE *e, const EVP_CIPHER **cipher, const int **nids,
 515                 int nid)
 516 {
 517     /* No specific cipher => return a list of supported nids ... */
 518     if (!cipher) {
 519         *nids = padlock_cipher_nids;
 520         return padlock_cipher_nids_num;
 521     }
 522
 523     /* ... or the requested "cipher" otherwise */
 524     switch (nid) {
 525     case NID_aes_128_ecb:
 526         *cipher = padlock_aes_128_ecb();
 527         break;
 528     case NID_aes_128_cbc:
 529         *cipher = padlock_aes_128_cbc();
 530         break;
 531     case NID_aes_128_cfb:
 532         *cipher = padlock_aes_128_cfb();
 533         break;
 534     case NID_aes_128_ofb:
 535         *cipher = padlock_aes_128_ofb();
 536         break;
 537     case NID_aes_128_ctr:
 538         *cipher = padlock_aes_128_ctr();
 539         break;
 540
 541     case NID_aes_192_ecb:
 542         *cipher = padlock_aes_192_ecb();
 543         break;
 544     case NID_aes_192_cbc:
 545         *cipher = padlock_aes_192_cbc();
 546         break;
 547     case NID_aes_192_cfb:
 548         *cipher = padlock_aes_192_cfb();
 549         break;
 550     case NID_aes_192_ofb:
 551         *cipher = padlock_aes_192_ofb();
 552         break;
 553     case NID_aes_192_ctr:
 554         *cipher = padlock_aes_192_ctr();
 555         break;
 556
 557     case NID_aes_256_ecb:
 558         *cipher = padlock_aes_256_ecb();
 559         break;
 560     case NID_aes_256_cbc:
 561         *cipher = padlock_aes_256_cbc();
 562         break;
 563     case NID_aes_256_cfb:
 564         *cipher = padlock_aes_256_cfb();
 565         break;
 566     case NID_aes_256_ofb:
 567         *cipher = padlock_aes_256_ofb();
 568         break;
 569     case NID_aes_256_ctr:
 570         *cipher = padlock_aes_256_ctr();
 571         break;
 572
 573     default:
 574         /* Sorry, we don't support this NID */
 575         *cipher = NULL;
 576         return 0;
 577     }
 578
 579     return 1;
 580 }
 581
 582 /* Prepare the encryption key for PadLock usage */
 583 static int
 584 padlock_aes_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,
 585                      const unsigned char *iv, int enc)
 586 {
 587     struct padlock_cipher_data *cdata;
 588     int key_len = EVP_CIPHER_CTX_key_length(ctx) * 8;
 589     unsigned long mode = EVP_CIPHER_CTX_mode(ctx);
 590
 591     if (key == NULL)
 592         return 0;               /* ERROR */
 593
 594     cdata = ALIGNED_CIPHER_DATA(ctx);
 595     memset(cdata, 0, sizeof(*cdata));
 596
 597     /* Prepare Control word. */
 598     if (mode == EVP_CIPH_OFB_MODE || mode == EVP_CIPH_CTR_MODE)
 599         cdata->cword.b.encdec = 0;
 600     else
 601         cdata->cword.b.encdec = (EVP_CIPHER_CTX_encrypting(ctx) == 0);
 602     cdata->cword.b.rounds = 10 + (key_len - 128) / 32;
 603     cdata->cword.b.ksize = (key_len - 128) / 64;
 604
 605     switch (key_len) {
 606     case 128:
 607         /*
 608          * PadLock can generate an extended key for AES128 in hardware
 609          */
 610         memcpy(cdata->ks.rd_key, key, AES_KEY_SIZE_128);
 611         cdata->cword.b.keygen = 0;
 612         break;
 613
 614     case 192:
 615     case 256:
 616         /*
 617          * Generate an extended AES key in software. Needed for AES192/AES256
 618          */
 619         /*
 620          * Well, the above applies to Stepping 8 CPUs and is listed as
 621          * hardware errata. They most likely will fix it at some point and
 622          * then a check for stepping would be due here.
 623          */
 624         if ((mode == EVP_CIPH_ECB_MODE || mode == EVP_CIPH_CBC_MODE)
 625             && !enc)
 626             AES_set_decrypt_key(key, key_len, &cdata->ks);
 627         else
 628             AES_set_encrypt_key(key, key_len, &cdata->ks);
 629 #   ifndef AES_ASM
 630         /*
 631          * OpenSSL C functions use byte-swapped extended key.
 632          */
 633         padlock_key_bswap(&cdata->ks);
 634 #   endif
 635         cdata->cword.b.keygen = 1;
 636         break;
 637
 638     default:
 639         /* ERROR */
 640         return 0;
 641     }
 642
 643     /*
 644      * This is done to cover for cases when user reuses the
 645      * context for new key. The catch is that if we don't do
 646      * this, padlock_eas_cipher might proceed with old key...
 647      */
 648     padlock_reload_key();
 649
 650     return 1;
 651 }
 652
 653 /* ===== Random Number Generator ===== */
 654 /*
 655  * This code is not engaged. The reason is that it does not comply
 656  * with recommendations for VIA RNG usage for secure applications
 657  * (posted at http://www.via.com.tw/en/viac3/c3.jsp) nor does it
 658  * provide meaningful error control...
 659  */
 660 /*
 661  * Wrapper that provides an interface between the API and the raw PadLock
 662  * RNG
 663  */
 664 static int padlock_rand_bytes(unsigned char *output, int count)
 665 {
 666     unsigned int eax, buf;
 667
 668     while (count >= 8) {
 669         eax = padlock_xstore(output, 0);
 670         if (!(eax & (1 << 6)))
 671             return 0;           /* RNG disabled */
 672         /* this ---vv--- covers DC bias, Raw Bits and String Filter */
 673         if (eax & (0x1F << 10))
 674             return 0;
 675         if ((eax & 0x1F) == 0)
 676             continue;           /* no data, retry... */
 677         if ((eax & 0x1F) != 8)
 678             return 0;           /* fatal failure...  */
 679         output += 8;
 680         count -= 8;
 681     }
 682     while (count > 0) {
 683         eax = padlock_xstore(&buf, 3);
 684         if (!(eax & (1 << 6)))
 685             return 0;           /* RNG disabled */
 686         /* this ---vv--- covers DC bias, Raw Bits and String Filter */
 687         if (eax & (0x1F << 10))
 688             return 0;
 689         if ((eax & 0x1F) == 0)
 690             continue;           /* no data, retry... */
 691         if ((eax & 0x1F) != 1)
 692             return 0;           /* fatal failure...  */
 693         *output++ = (unsigned char)buf;
 694         count--;
 695     }
 696     OPENSSL_cleanse(&buf, sizeof(buf));
 697
 698     return 1;
 699 }
 700
 701 /* Dummy but necessary function */
 702 static int padlock_rand_status(void)
 703 {
 704     return 1;
 705 }
 706
 707 /* Prepare structure for registration */
 708 static RAND_METHOD padlock_rand = {
 709     NULL,                       /* seed */
 710     padlock_rand_bytes,         /* bytes */
 711     NULL,                       /* cleanup */
 712     NULL,                       /* add */
 713     padlock_rand_bytes,         /* pseudorand */
 714     padlock_rand_status,        /* rand status */
 715 };
 716
 717 #  endif                        /* COMPILE_HW_PADLOCK */
 718 # endif                         /* !OPENSSL_NO_HW_PADLOCK */
 719 #endif                          /* !OPENSSL_NO_HW */
 720
 721 #if defined(OPENSSL_NO_HW) || defined(OPENSSL_NO_HW_PADLOCK) \
 722         || !defined(COMPILE_HW_PADLOCK)
 723 # ifndef OPENSSL_NO_DYNAMIC_ENGINE
 724 OPENSSL_EXPORT
 725     int bind_engine(ENGINE *e, const char *id, const dynamic_fns *fns);
 726 OPENSSL_EXPORT
 727     int bind_engine(ENGINE *e, const char *id, const dynamic_fns *fns)
 728 {
 729     return 0;
 730 }
 731
 732 IMPLEMENT_DYNAMIC_CHECK_FN()
 733 # endif
 734 #endif