engines/e_padlock.c

   1 /*
   2  * Copyright 2004-2018 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (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 /*
  11  * This file uses the low level AES functions (which are deprecated for
  12  * non-internal use) in order to implement the padlock engine AES ciphers.
  13  */
  14 #define OPENSSL_SUPPRESS_DEPRECATED
  15
  16 #include <stdio.h>
  17 #include <string.h>
  18
  19 #include <openssl/opensslconf.h>
  20 #include <openssl/crypto.h>
  21 #include <openssl/engine.h>
  22 #include <openssl/evp.h>
  23 #include <openssl/aes.h>
  24 #include <openssl/rand.h>
  25 #include <openssl/err.h>
  26 #include <openssl/modes.h>
  27
  28 #ifndef OPENSSL_NO_PADLOCKENG
  29
  30 /*
  31  * VIA PadLock AES is available *ONLY* on some x86 CPUs. Not only that it
  32  * doesn't exist elsewhere, but it even can't be compiled on other platforms!
  33  */
  34
  35 # undef COMPILE_PADLOCKENG
  36 # if defined(PADLOCK_ASM)
  37 #  define COMPILE_PADLOCKENG
  38 #  ifdef OPENSSL_NO_DYNAMIC_ENGINE
  39 static ENGINE *ENGINE_padlock(void);
  40 #  endif
  41 # endif
  42
  43 # ifdef OPENSSL_NO_DYNAMIC_ENGINE
  44 void engine_load_padlock_int(void);
  45 void engine_load_padlock_int(void)
  46 {
  47 /* On non-x86 CPUs it just returns. */
  48 #  ifdef COMPILE_PADLOCKENG
  49     ENGINE *toadd = ENGINE_padlock();
  50     if (!toadd)
  51         return;
  52     ENGINE_add(toadd);
  53     ENGINE_free(toadd);
  54     ERR_clear_error();
  55 #  endif
  56 }
  57
  58 # endif
  59
  60 # ifdef COMPILE_PADLOCKENG
  61
  62 /* Function for ENGINE detection and control */
  63 static int padlock_available(void);
  64 static int padlock_init(ENGINE *e);
  65
  66 /* RNG Stuff */
  67 static RAND_METHOD padlock_rand;
  68
  69 /* Cipher Stuff */
  70 static int padlock_ciphers(ENGINE *e, const EVP_CIPHER **cipher,
  71                            const int **nids, int nid);
  72
  73 /* Engine names */
  74 static const char *padlock_id = "padlock";
  75 static char padlock_name[100];
  76
  77 /* Available features */
  78 static int padlock_use_ace = 0; /* Advanced Cryptography Engine */
  79 static int padlock_use_rng = 0; /* Random Number Generator */
  80
  81 /* ===== Engine "management" functions ===== */
  82
  83 /* Prepare the ENGINE structure for registration */
  84 static int padlock_bind_helper(ENGINE *e)
  85 {
  86     /* Check available features */
  87     padlock_available();
  88
  89     /*
  90      * RNG is currently disabled for reasons discussed in commentary just
  91      * before padlock_rand_bytes function.
  92      */
  93     padlock_use_rng = 0;
  94
  95     /* Generate a nice engine name with available features */
  96     BIO_snprintf(padlock_name, sizeof(padlock_name),
  97                  "VIA PadLock (%s, %s)",
  98                  padlock_use_rng ? "RNG" : "no-RNG",
  99                  padlock_use_ace ? "ACE" : "no-ACE");
 100
 101     /* Register everything or return with an error */
 102     if (!ENGINE_set_id(e, padlock_id) ||
 103         !ENGINE_set_name(e, padlock_name) ||
 104         !ENGINE_set_init_function(e, padlock_init) ||
 105         (padlock_use_ace && !ENGINE_set_ciphers(e, padlock_ciphers)) ||
 106         (padlock_use_rng && !ENGINE_set_RAND(e, &padlock_rand))) {
 107         return 0;
 108     }
 109
 110     /* Everything looks good */
 111     return 1;
 112 }
 113
 114 #  ifdef OPENSSL_NO_DYNAMIC_ENGINE
 115 /* Constructor */
 116 static ENGINE *ENGINE_padlock(void)
 117 {
 118     ENGINE *eng = ENGINE_new();
 119
 120     if (eng == NULL) {
 121         return NULL;
 122     }
 123
 124     if (!padlock_bind_helper(eng)) {
 125         ENGINE_free(eng);
 126         return NULL;
 127     }
 128
 129     return eng;
 130 }
 131 #  endif
 132
 133 /* Check availability of the engine */
 134 static int padlock_init(ENGINE *e)
 135 {
 136     return (padlock_use_rng || padlock_use_ace);
 137 }
 138
 139 /*
 140  * This stuff is needed if this ENGINE is being compiled into a
 141  * self-contained shared-library.
 142  */
 143 #  ifndef OPENSSL_NO_DYNAMIC_ENGINE
 144 static int padlock_bind_fn(ENGINE *e, const char *id)
 145 {
 146     if (id && (strcmp(id, padlock_id) != 0)) {
 147         return 0;
 148     }
 149
 150     if (!padlock_bind_helper(e)) {
 151         return 0;
 152     }
 153
 154     return 1;
 155 }
 156
 157 IMPLEMENT_DYNAMIC_CHECK_FN()
 158 IMPLEMENT_DYNAMIC_BIND_FN(padlock_bind_fn)
 159 #  endif                       /* !OPENSSL_NO_DYNAMIC_ENGINE */
 160 /* ===== Here comes the "real" engine ===== */
 161
 162 /* Some AES-related constants */
 163 #  define AES_BLOCK_SIZE          16
 164 #  define AES_KEY_SIZE_128        16
 165 #  define AES_KEY_SIZE_192        24
 166 #  define AES_KEY_SIZE_256        32
 167     /*
 168      * Here we store the status information relevant to the current context.
 169      */
 170     /*
 171      * BIG FAT WARNING: Inline assembler in PADLOCK_XCRYPT_ASM() depends on
 172      * the order of items in this structure.  Don't blindly modify, reorder,
 173      * etc!
 174      */
 175 struct padlock_cipher_data {
 176     unsigned char iv[AES_BLOCK_SIZE]; /* Initialization vector */
 177     union {
 178         unsigned int pad[4];
 179         struct {
 180             int rounds:4;
 181             int dgst:1;         /* n/a in C3 */
 182             int align:1;        /* n/a in C3 */
 183             int ciphr:1;        /* n/a in C3 */
 184             unsigned int keygen:1;
 185             int interm:1;
 186             unsigned int encdec:1;
 187             int ksize:2;
 188         } b;
 189     } cword;                    /* Control word */
 190     AES_KEY ks;                 /* Encryption key */
 191 };
 192
 193 /* Interface to assembler module */
 194 unsigned int padlock_capability(void);
 195 void padlock_key_bswap(AES_KEY *key);
 196 void padlock_verify_context(struct padlock_cipher_data *ctx);
 197 void padlock_reload_key(void);
 198 void padlock_aes_block(void *out, const void *inp,
 199                        struct padlock_cipher_data *ctx);
 200 int padlock_ecb_encrypt(void *out, const void *inp,
 201                         struct padlock_cipher_data *ctx, size_t len);
 202 int padlock_cbc_encrypt(void *out, const void *inp,
 203                         struct padlock_cipher_data *ctx, size_t len);
 204 int padlock_cfb_encrypt(void *out, const void *inp,
 205                         struct padlock_cipher_data *ctx, size_t len);
 206 int padlock_ofb_encrypt(void *out, const void *inp,
 207                         struct padlock_cipher_data *ctx, size_t len);
 208 int padlock_ctr32_encrypt(void *out, const void *inp,
 209                           struct padlock_cipher_data *ctx, size_t len);
 210 int padlock_xstore(void *out, int edx);
 211 void padlock_sha1_oneshot(void *ctx, const void *inp, size_t len);
 212 void padlock_sha1(void *ctx, const void *inp, size_t len);
 213 void padlock_sha256_oneshot(void *ctx, const void *inp, size_t len);
 214 void padlock_sha256(void *ctx, const void *inp, size_t len);
 215
 216 /*
 217  * Load supported features of the CPU to see if the PadLock is available.
 218  */
 219 static int padlock_available(void)
 220 {
 221     unsigned int edx = padlock_capability();
 222
 223     /* Fill up some flags */
 224     padlock_use_ace = ((edx & (0x3 << 6)) == (0x3 << 6));
 225     padlock_use_rng = ((edx & (0x3 << 2)) == (0x3 << 2));
 226
 227     return padlock_use_ace + padlock_use_rng;
 228 }
 229
 230 /* ===== AES encryption/decryption ===== */
 231
 232 #  if defined(NID_aes_128_cfb128) && ! defined (NID_aes_128_cfb)
 233 #   define NID_aes_128_cfb NID_aes_128_cfb128
 234 #  endif
 235
 236 #  if defined(NID_aes_128_ofb128) && ! defined (NID_aes_128_ofb)
 237 #   define NID_aes_128_ofb NID_aes_128_ofb128
 238 #  endif
 239
 240 #  if defined(NID_aes_192_cfb128) && ! defined (NID_aes_192_cfb)
 241 #   define NID_aes_192_cfb NID_aes_192_cfb128
 242 #  endif
 243
 244 #  if defined(NID_aes_192_ofb128) && ! defined (NID_aes_192_ofb)
 245 #   define NID_aes_192_ofb NID_aes_192_ofb128
 246 #  endif
 247
 248 #  if defined(NID_aes_256_cfb128) && ! defined (NID_aes_256_cfb)
 249 #   define NID_aes_256_cfb NID_aes_256_cfb128
 250 #  endif
 251
 252 #  if defined(NID_aes_256_ofb128) && ! defined (NID_aes_256_ofb)
 253 #   define NID_aes_256_ofb NID_aes_256_ofb128
 254 #  endif
 255
 256 /* List of supported ciphers. */
 257 static const int padlock_cipher_nids[] = {
 258     NID_aes_128_ecb,
 259     NID_aes_128_cbc,
 260     NID_aes_128_cfb,
 261     NID_aes_128_ofb,
 262     NID_aes_128_ctr,
 263
 264     NID_aes_192_ecb,
 265     NID_aes_192_cbc,
 266     NID_aes_192_cfb,
 267     NID_aes_192_ofb,
 268     NID_aes_192_ctr,
 269
 270     NID_aes_256_ecb,
 271     NID_aes_256_cbc,
 272     NID_aes_256_cfb,
 273     NID_aes_256_ofb,
 274     NID_aes_256_ctr
 275 };
 276
 277 static int padlock_cipher_nids_num = (sizeof(padlock_cipher_nids) /
 278                                       sizeof(padlock_cipher_nids[0]));
 279
 280 /* Function prototypes ... */
 281 static int padlock_aes_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,
 282                                 const unsigned char *iv, int enc);
 283
 284 #  define NEAREST_ALIGNED(ptr) ( (unsigned char *)(ptr) +         \
 285         ( (0x10 - ((size_t)(ptr) & 0x0F)) & 0x0F )      )
 286 #  define ALIGNED_CIPHER_DATA(ctx) ((struct padlock_cipher_data *)\
 287         NEAREST_ALIGNED(EVP_CIPHER_CTX_get_cipher_data(ctx)))
 288
 289 static int
 290 padlock_ecb_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
 291                    const unsigned char *in_arg, size_t nbytes)
 292 {
 293     return padlock_ecb_encrypt(out_arg, in_arg,
 294                                ALIGNED_CIPHER_DATA(ctx), nbytes);
 295 }
 296
 297 static int
 298 padlock_cbc_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
 299                    const unsigned char *in_arg, size_t nbytes)
 300 {
 301     struct padlock_cipher_data *cdata = ALIGNED_CIPHER_DATA(ctx);
 302     int ret;
 303
 304     memcpy(cdata->iv, EVP_CIPHER_CTX_iv(ctx), AES_BLOCK_SIZE);
 305     if ((ret = padlock_cbc_encrypt(out_arg, in_arg, cdata, nbytes)))
 306         memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), cdata->iv, AES_BLOCK_SIZE);
 307     return ret;
 308 }
 309
 310 static int
 311 padlock_cfb_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
 312                    const unsigned char *in_arg, size_t nbytes)
 313 {
 314     struct padlock_cipher_data *cdata = ALIGNED_CIPHER_DATA(ctx);
 315     size_t chunk;
 316
 317     if ((chunk = EVP_CIPHER_CTX_num(ctx))) {   /* borrow chunk variable */
 318         unsigned char *ivp = EVP_CIPHER_CTX_iv_noconst(ctx);
 319
 320         if (chunk >= AES_BLOCK_SIZE)
 321             return 0;           /* bogus value */
 322
 323         if (EVP_CIPHER_CTX_encrypting(ctx))
 324             while (chunk < AES_BLOCK_SIZE && nbytes != 0) {
 325                 ivp[chunk] = *(out_arg++) = *(in_arg++) ^ ivp[chunk];
 326                 chunk++, nbytes--;
 327         } else
 328             while (chunk < AES_BLOCK_SIZE && nbytes != 0) {
 329                 unsigned char c = *(in_arg++);
 330                 *(out_arg++) = c ^ ivp[chunk];
 331                 ivp[chunk++] = c, nbytes--;
 332             }
 333
 334         EVP_CIPHER_CTX_set_num(ctx, chunk % AES_BLOCK_SIZE);
 335     }
 336
 337     if (nbytes == 0)
 338         return 1;
 339
 340     memcpy(cdata->iv, EVP_CIPHER_CTX_iv(ctx), AES_BLOCK_SIZE);
 341
 342     if ((chunk = nbytes & ~(AES_BLOCK_SIZE - 1))) {
 343         if (!padlock_cfb_encrypt(out_arg, in_arg, cdata, chunk))
 344             return 0;
 345         nbytes -= chunk;
 346     }
 347
 348     if (nbytes) {
 349         unsigned char *ivp = cdata->iv;
 350
 351         out_arg += chunk;
 352         in_arg += chunk;
 353         EVP_CIPHER_CTX_set_num(ctx, nbytes);
 354         if (cdata->cword.b.encdec) {
 355             cdata->cword.b.encdec = 0;
 356             padlock_reload_key();
 357             padlock_aes_block(ivp, ivp, cdata);
 358             cdata->cword.b.encdec = 1;
 359             padlock_reload_key();
 360             while (nbytes) {
 361                 unsigned char c = *(in_arg++);
 362                 *(out_arg++) = c ^ *ivp;
 363                 *(ivp++) = c, nbytes--;
 364             }
 365         } else {
 366             padlock_reload_key();
 367             padlock_aes_block(ivp, ivp, cdata);
 368             padlock_reload_key();
 369             while (nbytes) {
 370                 *ivp = *(out_arg++) = *(in_arg++) ^ *ivp;
 371                 ivp++, nbytes--;
 372             }
 373         }
 374     }
 375
 376     memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), cdata->iv, AES_BLOCK_SIZE);
 377
 378     return 1;
 379 }
 380
 381 static int
 382 padlock_ofb_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
 383                    const unsigned char *in_arg, size_t nbytes)
 384 {
 385     struct padlock_cipher_data *cdata = ALIGNED_CIPHER_DATA(ctx);
 386     size_t chunk;
 387
 388     /*
 389      * ctx->num is maintained in byte-oriented modes, such as CFB and OFB...
 390      */
 391     if ((chunk = EVP_CIPHER_CTX_num(ctx))) {   /* borrow chunk variable */
 392         unsigned char *ivp = EVP_CIPHER_CTX_iv_noconst(ctx);
 393
 394         if (chunk >= AES_BLOCK_SIZE)
 395             return 0;           /* bogus value */
 396
 397         while (chunk < AES_BLOCK_SIZE && nbytes != 0) {
 398             *(out_arg++) = *(in_arg++) ^ ivp[chunk];
 399             chunk++, nbytes--;
 400         }
 401
 402         EVP_CIPHER_CTX_set_num(ctx, chunk % AES_BLOCK_SIZE);
 403     }
 404
 405     if (nbytes == 0)
 406         return 1;
 407
 408     memcpy(cdata->iv, EVP_CIPHER_CTX_iv(ctx), AES_BLOCK_SIZE);
 409
 410     if ((chunk = nbytes & ~(AES_BLOCK_SIZE - 1))) {
 411         if (!padlock_ofb_encrypt(out_arg, in_arg, cdata, chunk))
 412             return 0;
 413         nbytes -= chunk;
 414     }
 415
 416     if (nbytes) {
 417         unsigned char *ivp = cdata->iv;
 418
 419         out_arg += chunk;
 420         in_arg += chunk;
 421         EVP_CIPHER_CTX_set_num(ctx, nbytes);
 422         padlock_reload_key();   /* empirically found */
 423         padlock_aes_block(ivp, ivp, cdata);
 424         padlock_reload_key();   /* empirically found */
 425         while (nbytes) {
 426             *(out_arg++) = *(in_arg++) ^ *ivp;
 427             ivp++, nbytes--;
 428         }
 429     }
 430
 431     memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), cdata->iv, AES_BLOCK_SIZE);
 432
 433     return 1;
 434 }
 435
 436 static void padlock_ctr32_encrypt_glue(const unsigned char *in,
 437                                        unsigned char *out, size_t blocks,
 438                                        struct padlock_cipher_data *ctx,
 439                                        const unsigned char *ivec)
 440 {
 441     memcpy(ctx->iv, ivec, AES_BLOCK_SIZE);
 442     padlock_ctr32_encrypt(out, in, ctx, AES_BLOCK_SIZE * blocks);
 443 }
 444
 445 static int
 446 padlock_ctr_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
 447                    const unsigned char *in_arg, size_t nbytes)
 448 {
 449     struct padlock_cipher_data *cdata = ALIGNED_CIPHER_DATA(ctx);
 450     unsigned int num = EVP_CIPHER_CTX_num(ctx);
 451
 452     CRYPTO_ctr128_encrypt_ctr32(in_arg, out_arg, nbytes,
 453                                 cdata, EVP_CIPHER_CTX_iv_noconst(ctx),
 454                                 EVP_CIPHER_CTX_buf_noconst(ctx), &num,
 455                                 (ctr128_f) padlock_ctr32_encrypt_glue);
 456
 457     EVP_CIPHER_CTX_set_num(ctx, (size_t)num);
 458     return 1;
 459 }
 460
 461 #  define EVP_CIPHER_block_size_ECB       AES_BLOCK_SIZE
 462 #  define EVP_CIPHER_block_size_CBC       AES_BLOCK_SIZE
 463 #  define EVP_CIPHER_block_size_OFB       1
 464 #  define EVP_CIPHER_block_size_CFB       1
 465 #  define EVP_CIPHER_block_size_CTR       1
 466
 467 /*
 468  * Declaring so many ciphers by hand would be a pain. Instead introduce a bit
 469  * of preprocessor magic :-)
 470  */
 471 #  define DECLARE_AES_EVP(ksize,lmode,umode)      \
 472 static EVP_CIPHER *_hidden_aes_##ksize##_##lmode = NULL; \
 473 static const EVP_CIPHER *padlock_aes_##ksize##_##lmode(void) \
 474 {                                                                       \
 475     if (_hidden_aes_##ksize##_##lmode == NULL                           \
 476         && ((_hidden_aes_##ksize##_##lmode =                            \
 477              EVP_CIPHER_meth_new(NID_aes_##ksize##_##lmode,             \
 478                                  EVP_CIPHER_block_size_##umode,         \
 479                                  AES_KEY_SIZE_##ksize)) == NULL         \
 480             || !EVP_CIPHER_meth_set_iv_length(_hidden_aes_##ksize##_##lmode, \
 481                                               AES_BLOCK_SIZE)           \
 482             || !EVP_CIPHER_meth_set_flags(_hidden_aes_##ksize##_##lmode, \
 483                                           0 | EVP_CIPH_##umode##_MODE)  \
 484             || !EVP_CIPHER_meth_set_init(_hidden_aes_##ksize##_##lmode, \
 485                                          padlock_aes_init_key)          \
 486             || !EVP_CIPHER_meth_set_do_cipher(_hidden_aes_##ksize##_##lmode, \
 487                                               padlock_##lmode##_cipher) \
 488             || !EVP_CIPHER_meth_set_impl_ctx_size(_hidden_aes_##ksize##_##lmode, \
 489                                                   sizeof(struct padlock_cipher_data) + 16) \
 490             || !EVP_CIPHER_meth_set_set_asn1_params(_hidden_aes_##ksize##_##lmode, \
 491                                                     EVP_CIPHER_set_asn1_iv) \
 492             || !EVP_CIPHER_meth_set_get_asn1_params(_hidden_aes_##ksize##_##lmode, \
 493                                                     EVP_CIPHER_get_asn1_iv))) { \
 494         EVP_CIPHER_meth_free(_hidden_aes_##ksize##_##lmode);            \
 495         _hidden_aes_##ksize##_##lmode = NULL;                           \
 496     }                                                                   \
 497     return _hidden_aes_##ksize##_##lmode;                               \
 498 }
 499
 500 DECLARE_AES_EVP(128, ecb, ECB)
 501 DECLARE_AES_EVP(128, cbc, CBC)
 502 DECLARE_AES_EVP(128, cfb, CFB)
 503 DECLARE_AES_EVP(128, ofb, OFB)
 504 DECLARE_AES_EVP(128, ctr, CTR)
 505
 506 DECLARE_AES_EVP(192, ecb, ECB)
 507 DECLARE_AES_EVP(192, cbc, CBC)
 508 DECLARE_AES_EVP(192, cfb, CFB)
 509 DECLARE_AES_EVP(192, ofb, OFB)
 510 DECLARE_AES_EVP(192, ctr, CTR)
 511
 512 DECLARE_AES_EVP(256, ecb, ECB)
 513 DECLARE_AES_EVP(256, cbc, CBC)
 514 DECLARE_AES_EVP(256, cfb, CFB)
 515 DECLARE_AES_EVP(256, ofb, OFB)
 516 DECLARE_AES_EVP(256, ctr, CTR)
 517
 518 static int
 519 padlock_ciphers(ENGINE *e, const EVP_CIPHER **cipher, const int **nids,
 520                 int nid)
 521 {
 522     /* No specific cipher => return a list of supported nids ... */
 523     if (!cipher) {
 524         *nids = padlock_cipher_nids;
 525         return padlock_cipher_nids_num;
 526     }
 527
 528     /* ... or the requested "cipher" otherwise */
 529     switch (nid) {
 530     case NID_aes_128_ecb:
 531         *cipher = padlock_aes_128_ecb();
 532         break;
 533     case NID_aes_128_cbc:
 534         *cipher = padlock_aes_128_cbc();
 535         break;
 536     case NID_aes_128_cfb:
 537         *cipher = padlock_aes_128_cfb();
 538         break;
 539     case NID_aes_128_ofb:
 540         *cipher = padlock_aes_128_ofb();
 541         break;
 542     case NID_aes_128_ctr:
 543         *cipher = padlock_aes_128_ctr();
 544         break;
 545
 546     case NID_aes_192_ecb:
 547         *cipher = padlock_aes_192_ecb();
 548         break;
 549     case NID_aes_192_cbc:
 550         *cipher = padlock_aes_192_cbc();
 551         break;
 552     case NID_aes_192_cfb:
 553         *cipher = padlock_aes_192_cfb();
 554         break;
 555     case NID_aes_192_ofb:
 556         *cipher = padlock_aes_192_ofb();
 557         break;
 558     case NID_aes_192_ctr:
 559         *cipher = padlock_aes_192_ctr();
 560         break;
 561
 562     case NID_aes_256_ecb:
 563         *cipher = padlock_aes_256_ecb();
 564         break;
 565     case NID_aes_256_cbc:
 566         *cipher = padlock_aes_256_cbc();
 567         break;
 568     case NID_aes_256_cfb:
 569         *cipher = padlock_aes_256_cfb();
 570         break;
 571     case NID_aes_256_ofb:
 572         *cipher = padlock_aes_256_ofb();
 573         break;
 574     case NID_aes_256_ctr:
 575         *cipher = padlock_aes_256_ctr();
 576         break;
 577
 578     default:
 579         /* Sorry, we don't support this NID */
 580         *cipher = NULL;
 581         return 0;
 582     }
 583
 584     return 1;
 585 }
 586
 587 /* Prepare the encryption key for PadLock usage */
 588 static int
 589 padlock_aes_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,
 590                      const unsigned char *iv, int enc)
 591 {
 592     struct padlock_cipher_data *cdata;
 593     int key_len = EVP_CIPHER_CTX_key_length(ctx) * 8;
 594     unsigned long mode = EVP_CIPHER_CTX_mode(ctx);
 595
 596     if (key == NULL)
 597         return 0;               /* ERROR */
 598
 599     cdata = ALIGNED_CIPHER_DATA(ctx);
 600     memset(cdata, 0, sizeof(*cdata));
 601
 602     /* Prepare Control word. */
 603     if (mode == EVP_CIPH_OFB_MODE || mode == EVP_CIPH_CTR_MODE)
 604         cdata->cword.b.encdec = 0;
 605     else
 606         cdata->cword.b.encdec = (EVP_CIPHER_CTX_encrypting(ctx) == 0);
 607     cdata->cword.b.rounds = 10 + (key_len - 128) / 32;
 608     cdata->cword.b.ksize = (key_len - 128) / 64;
 609
 610     switch (key_len) {
 611     case 128:
 612         /*
 613          * PadLock can generate an extended key for AES128 in hardware
 614          */
 615         memcpy(cdata->ks.rd_key, key, AES_KEY_SIZE_128);
 616         cdata->cword.b.keygen = 0;
 617         break;
 618
 619     case 192:
 620     case 256:
 621         /*
 622          * Generate an extended AES key in software. Needed for AES192/AES256
 623          */
 624         /*
 625          * Well, the above applies to Stepping 8 CPUs and is listed as
 626          * hardware errata. They most likely will fix it at some point and
 627          * then a check for stepping would be due here.
 628          */
 629         if ((mode == EVP_CIPH_ECB_MODE || mode == EVP_CIPH_CBC_MODE)
 630             && !enc)
 631             AES_set_decrypt_key(key, key_len, &cdata->ks);
 632         else
 633             AES_set_encrypt_key(key, key_len, &cdata->ks);
 634 #  ifndef AES_ASM
 635         /*
 636          * OpenSSL C functions use byte-swapped extended key.
 637          */
 638         padlock_key_bswap(&cdata->ks);
 639 #  endif
 640         cdata->cword.b.keygen = 1;
 641         break;
 642
 643     default:
 644         /* ERROR */
 645         return 0;
 646     }
 647
 648     /*
 649      * This is done to cover for cases when user reuses the
 650      * context for new key. The catch is that if we don't do
 651      * this, padlock_eas_cipher might proceed with old key...
 652      */
 653     padlock_reload_key();
 654
 655     return 1;
 656 }
 657
 658 /* ===== Random Number Generator ===== */
 659 /*
 660  * This code is not engaged. The reason is that it does not comply
 661  * with recommendations for VIA RNG usage for secure applications
 662  * (posted at http://www.via.com.tw/en/viac3/c3.jsp) nor does it
 663  * provide meaningful error control...
 664  */
 665 /*
 666  * Wrapper that provides an interface between the API and the raw PadLock
 667  * RNG
 668  */
 669 static int padlock_rand_bytes(unsigned char *output, int count)
 670 {
 671     unsigned int eax, buf;
 672
 673     while (count >= 8) {
 674         eax = padlock_xstore(output, 0);
 675         if (!(eax & (1 << 6)))
 676             return 0;           /* RNG disabled */
 677         /* this ---vv--- covers DC bias, Raw Bits and String Filter */
 678         if (eax & (0x1F << 10))
 679             return 0;
 680         if ((eax & 0x1F) == 0)
 681             continue;           /* no data, retry... */
 682         if ((eax & 0x1F) != 8)
 683             return 0;           /* fatal failure...  */
 684         output += 8;
 685         count -= 8;
 686     }
 687     while (count > 0) {
 688         eax = padlock_xstore(&buf, 3);
 689         if (!(eax & (1 << 6)))
 690             return 0;           /* RNG disabled */
 691         /* this ---vv--- covers DC bias, Raw Bits and String Filter */
 692         if (eax & (0x1F << 10))
 693             return 0;
 694         if ((eax & 0x1F) == 0)
 695             continue;           /* no data, retry... */
 696         if ((eax & 0x1F) != 1)
 697             return 0;           /* fatal failure...  */
 698         *output++ = (unsigned char)buf;
 699         count--;
 700     }
 701     OPENSSL_cleanse(&buf, sizeof(buf));
 702
 703     return 1;
 704 }
 705
 706 /* Dummy but necessary function */
 707 static int padlock_rand_status(void)
 708 {
 709     return 1;
 710 }
 711
 712 /* Prepare structure for registration */
 713 static RAND_METHOD padlock_rand = {
 714     NULL,                       /* seed */
 715     padlock_rand_bytes,         /* bytes */
 716     NULL,                       /* cleanup */
 717     NULL,                       /* add */
 718     padlock_rand_bytes,         /* pseudorand */
 719     padlock_rand_status,        /* rand status */
 720 };
 721
 722 # endif                        /* COMPILE_PADLOCKENG */
 723 #endif                         /* !OPENSSL_NO_PADLOCKENG */
 724
 725 #if defined(OPENSSL_NO_PADLOCKENG) || !defined(COMPILE_PADLOCKENG)
 726 # ifndef OPENSSL_NO_DYNAMIC_ENGINE
 727 OPENSSL_EXPORT
 728     int bind_engine(ENGINE *e, const char *id, const dynamic_fns *fns);
 729 OPENSSL_EXPORT
 730     int bind_engine(ENGINE *e, const char *id, const dynamic_fns *fns)
 731 {
 732     return 0;
 733 }
 734
 735 IMPLEMENT_DYNAMIC_CHECK_FN()
 736 # endif
 737 #endif