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