engines/e_padlock.c

   1 /*
   2  * Copyright 2004-2016 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 /* Attempt to have a single source for both 0.9.7 and 0.9.8 :-) */
  26 #  if (OPENSSL_VERSION_NUMBER >= 0x00908000L)
  27 #   ifndef OPENSSL_NO_DYNAMIC_ENGINE
  28 #    define DYNAMIC_ENGINE
  29 #   endif
  30 #  elif (OPENSSL_VERSION_NUMBER >= 0x00907000L)
  31 #   ifdef ENGINE_DYNAMIC_SUPPORT
  32 #    define DYNAMIC_ENGINE
  33 #   endif
  34 #  else
  35 #   error "Only OpenSSL >= 0.9.7 is supported"
  36 #  endif
  37
  38 /*
  39  * VIA PadLock AES is available *ONLY* on some x86 CPUs. Not only that it
  40  * doesn't exist elsewhere, but it even can't be compiled on other platforms!
  41  */
  42
  43 #  undef COMPILE_HW_PADLOCK
  44 #  if !defined(I386_ONLY) && defined(PADLOCK_ASM)
  45 #   define COMPILE_HW_PADLOCK
  46 #   ifdef OPENSSL_NO_DYNAMIC_ENGINE
  47 static ENGINE *ENGINE_padlock(void);
  48 #   endif
  49 #  endif
  50
  51 #  ifdef OPENSSL_NO_DYNAMIC_ENGINE
  52 void engine_load_padlock_int(void);
  53 void engine_load_padlock_int(void)
  54 {
  55 /* On non-x86 CPUs it just returns. */
  56 #   ifdef COMPILE_HW_PADLOCK
  57     ENGINE *toadd = ENGINE_padlock();
  58     if (!toadd)
  59         return;
  60     ENGINE_add(toadd);
  61     ENGINE_free(toadd);
  62     ERR_clear_error();
  63 #   endif
  64 }
  65
  66 #  endif
  67
  68 #  ifdef COMPILE_HW_PADLOCK
  69
  70 /* Function for ENGINE detection and control */
  71 static int padlock_available(void);
  72 static int padlock_init(ENGINE *e);
  73
  74 /* RNG Stuff */
  75 static RAND_METHOD padlock_rand;
  76
  77 /* Cipher Stuff */
  78 static int padlock_ciphers(ENGINE *e, const EVP_CIPHER **cipher,
  79                            const int **nids, int nid);
  80
  81 /* Engine names */
  82 static const char *padlock_id = "padlock";
  83 static char padlock_name[100];
  84
  85 /* Available features */
  86 static int padlock_use_ace = 0; /* Advanced Cryptography Engine */
  87 static int padlock_use_rng = 0; /* Random Number Generator */
  88
  89 /* ===== Engine "management" functions ===== */
  90
  91 /* Prepare the ENGINE structure for registration */
  92 static int padlock_bind_helper(ENGINE *e)
  93 {
  94     /* Check available features */
  95     padlock_available();
  96
  97     /*
  98      * RNG is currently disabled for reasons discussed in commentary just
  99      * before padlock_rand_bytes function.
 100      */
 101     padlock_use_rng = 0;
 102
 103     /* Generate a nice engine name with available features */
 104     BIO_snprintf(padlock_name, sizeof(padlock_name),
 105                  "VIA PadLock (%s, %s)",
 106                  padlock_use_rng ? "RNG" : "no-RNG",
 107                  padlock_use_ace ? "ACE" : "no-ACE");
 108
 109     /* Register everything or return with an error */
 110     if (!ENGINE_set_id(e, padlock_id) ||
 111         !ENGINE_set_name(e, padlock_name) ||
 112         !ENGINE_set_init_function(e, padlock_init) ||
 113         (padlock_use_ace && !ENGINE_set_ciphers(e, padlock_ciphers)) ||
 114         (padlock_use_rng && !ENGINE_set_RAND(e, &padlock_rand))) {
 115         return 0;
 116     }
 117
 118     /* Everything looks good */
 119     return 1;
 120 }
 121
 122 #   ifdef OPENSSL_NO_DYNAMIC_ENGINE
 123 /* Constructor */
 124 static ENGINE *ENGINE_padlock(void)
 125 {
 126     ENGINE *eng = ENGINE_new();
 127
 128     if (eng == NULL) {
 129         return NULL;
 130     }
 131
 132     if (!padlock_bind_helper(eng)) {
 133         ENGINE_free(eng);
 134         return NULL;
 135     }
 136
 137     return eng;
 138 }
 139 #   endif
 140
 141 /* Check availability of the engine */
 142 static int padlock_init(ENGINE *e)
 143 {
 144     return (padlock_use_rng || padlock_use_ace);
 145 }
 146
 147 /*
 148  * This stuff is needed if this ENGINE is being compiled into a
 149  * self-contained shared-library.
 150  */
 151 #   ifdef DYNAMIC_ENGINE
 152 static int padlock_bind_fn(ENGINE *e, const char *id)
 153 {
 154     if (id && (strcmp(id, padlock_id) != 0)) {
 155         return 0;
 156     }
 157
 158     if (!padlock_bind_helper(e)) {
 159         return 0;
 160     }
 161
 162     return 1;
 163 }
 164
 165 IMPLEMENT_DYNAMIC_CHECK_FN()
 166 IMPLEMENT_DYNAMIC_BIND_FN(padlock_bind_fn)
 167 #   endif                       /* DYNAMIC_ENGINE */
 168 /* ===== Here comes the "real" engine ===== */
 169
 170 /* Some AES-related constants */
 171 #   define AES_BLOCK_SIZE          16
 172 #   define AES_KEY_SIZE_128        16
 173 #   define AES_KEY_SIZE_192        24
 174 #   define AES_KEY_SIZE_256        32
 175     /*
 176      * Here we store the status information relevant to the current context.
 177      */
 178     /*
 179      * BIG FAT WARNING: Inline assembler in PADLOCK_XCRYPT_ASM() depends on
 180      * the order of items in this structure.  Don't blindly modify, reorder,
 181      * etc!
 182      */
 183 struct padlock_cipher_data {
 184     unsigned char iv[AES_BLOCK_SIZE]; /* Initialization vector */
 185     union {
 186         unsigned int pad[4];
 187         struct {
 188             int rounds:4;
 189             int dgst:1;         /* n/a in C3 */
 190             int align:1;        /* n/a in C3 */
 191             int ciphr:1;        /* n/a in C3 */
 192             unsigned int keygen:1;
 193             int interm:1;
 194             unsigned int encdec:1;
 195             int ksize:2;
 196         } b;
 197     } cword;                    /* Control word */
 198     AES_KEY ks;                 /* Encryption key */
 199 };
 200
 201 /* Interface to assembler module */
 202 unsigned int padlock_capability();
 203 void padlock_key_bswap(AES_KEY *key);
 204 void padlock_verify_context(struct padlock_cipher_data *ctx);
 205 void padlock_reload_key();
 206 void padlock_aes_block(void *out, const void *inp,
 207                        struct padlock_cipher_data *ctx);
 208 int padlock_ecb_encrypt(void *out, const void *inp,
 209                         struct padlock_cipher_data *ctx, size_t len);
 210 int padlock_cbc_encrypt(void *out, const void *inp,
 211                         struct padlock_cipher_data *ctx, size_t len);
 212 int padlock_cfb_encrypt(void *out, const void *inp,
 213                         struct padlock_cipher_data *ctx, size_t len);
 214 int padlock_ofb_encrypt(void *out, const void *inp,
 215                         struct padlock_cipher_data *ctx, size_t len);
 216 int padlock_ctr32_encrypt(void *out, const void *inp,
 217                           struct padlock_cipher_data *ctx, size_t len);
 218 int padlock_xstore(void *out, int edx);
 219 void padlock_sha1_oneshot(void *ctx, const void *inp, size_t len);
 220 void padlock_sha1(void *ctx, const void *inp, size_t len);
 221 void padlock_sha256_oneshot(void *ctx, const void *inp, size_t len);
 222 void padlock_sha256(void *ctx, const void *inp, size_t len);
 223
 224 /*
 225  * Load supported features of the CPU to see if the PadLock is available.
 226  */
 227 static int padlock_available(void)
 228 {
 229     unsigned int edx = padlock_capability();
 230
 231     /* Fill up some flags */
 232     padlock_use_ace = ((edx & (0x3 << 6)) == (0x3 << 6));
 233     padlock_use_rng = ((edx & (0x3 << 2)) == (0x3 << 2));
 234
 235     return padlock_use_ace + padlock_use_rng;
 236 }
 237
 238 /* ===== AES encryption/decryption ===== */
 239
 240 #   if defined(NID_aes_128_cfb128) && ! defined (NID_aes_128_cfb)
 241 #    define NID_aes_128_cfb NID_aes_128_cfb128
 242 #   endif
 243
 244 #   if defined(NID_aes_128_ofb128) && ! defined (NID_aes_128_ofb)
 245 #    define NID_aes_128_ofb NID_aes_128_ofb128
 246 #   endif
 247
 248 #   if defined(NID_aes_192_cfb128) && ! defined (NID_aes_192_cfb)
 249 #    define NID_aes_192_cfb NID_aes_192_cfb128
 250 #   endif
 251
 252 #   if defined(NID_aes_192_ofb128) && ! defined (NID_aes_192_ofb)
 253 #    define NID_aes_192_ofb NID_aes_192_ofb128
 254 #   endif
 255
 256 #   if defined(NID_aes_256_cfb128) && ! defined (NID_aes_256_cfb)
 257 #    define NID_aes_256_cfb NID_aes_256_cfb128
 258 #   endif
 259
 260 #   if defined(NID_aes_256_ofb128) && ! defined (NID_aes_256_ofb)
 261 #    define NID_aes_256_ofb NID_aes_256_ofb128
 262 #   endif
 263
 264 /* List of supported ciphers. */
 265 static const int padlock_cipher_nids[] = {
 266     NID_aes_128_ecb,
 267     NID_aes_128_cbc,
 268     NID_aes_128_cfb,
 269     NID_aes_128_ofb,
 270     NID_aes_128_ctr,
 271
 272     NID_aes_192_ecb,
 273     NID_aes_192_cbc,
 274     NID_aes_192_cfb,
 275     NID_aes_192_ofb,
 276     NID_aes_192_ctr,
 277
 278     NID_aes_256_ecb,
 279     NID_aes_256_cbc,
 280     NID_aes_256_cfb,
 281     NID_aes_256_ofb,
 282     NID_aes_256_ctr
 283 };
 284
 285 static int padlock_cipher_nids_num = (sizeof(padlock_cipher_nids) /
 286                                       sizeof(padlock_cipher_nids[0]));
 287
 288 /* Function prototypes ... */
 289 static int padlock_aes_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,
 290                                 const unsigned char *iv, int enc);
 291
 292 #   define NEAREST_ALIGNED(ptr) ( (unsigned char *)(ptr) +         \
 293         ( (0x10 - ((size_t)(ptr) & 0x0F)) & 0x0F )      )
 294 #   define ALIGNED_CIPHER_DATA(ctx) ((struct padlock_cipher_data *)\
 295         NEAREST_ALIGNED(EVP_CIPHER_CTX_get_cipher_data(ctx)))
 296
 297 static int
 298 padlock_ecb_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
 299                    const unsigned char *in_arg, size_t nbytes)
 300 {
 301     return padlock_ecb_encrypt(out_arg, in_arg,
 302                                ALIGNED_CIPHER_DATA(ctx), nbytes);
 303 }
 304
 305 static int
 306 padlock_cbc_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     int ret;
 311
 312     memcpy(cdata->iv, EVP_CIPHER_CTX_iv(ctx), AES_BLOCK_SIZE);
 313     if ((ret = padlock_cbc_encrypt(out_arg, in_arg, cdata, nbytes)))
 314         memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), cdata->iv, AES_BLOCK_SIZE);
 315     return ret;
 316 }
 317
 318 static int
 319 padlock_cfb_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
 320                    const unsigned char *in_arg, size_t nbytes)
 321 {
 322     struct padlock_cipher_data *cdata = ALIGNED_CIPHER_DATA(ctx);
 323     size_t chunk;
 324
 325     if ((chunk = EVP_CIPHER_CTX_num(ctx))) {   /* borrow chunk variable */
 326         unsigned char *ivp = EVP_CIPHER_CTX_iv_noconst(ctx);
 327
 328         if (chunk >= AES_BLOCK_SIZE)
 329             return 0;           /* bogus value */
 330
 331         if (EVP_CIPHER_CTX_encrypting(ctx))
 332             while (chunk < AES_BLOCK_SIZE && nbytes != 0) {
 333                 ivp[chunk] = *(out_arg++) = *(in_arg++) ^ ivp[chunk];
 334                 chunk++, nbytes--;
 335         } else
 336             while (chunk < AES_BLOCK_SIZE && nbytes != 0) {
 337                 unsigned char c = *(in_arg++);
 338                 *(out_arg++) = c ^ ivp[chunk];
 339                 ivp[chunk++] = c, nbytes--;
 340             }
 341
 342         EVP_CIPHER_CTX_set_num(ctx, chunk % AES_BLOCK_SIZE);
 343     }
 344
 345     if (nbytes == 0)
 346         return 1;
 347
 348     memcpy(cdata->iv, EVP_CIPHER_CTX_iv(ctx), AES_BLOCK_SIZE);
 349
 350     if ((chunk = nbytes & ~(AES_BLOCK_SIZE - 1))) {
 351         if (!padlock_cfb_encrypt(out_arg, in_arg, cdata, chunk))
 352             return 0;
 353         nbytes -= chunk;
 354     }
 355
 356     if (nbytes) {
 357         unsigned char *ivp = cdata->iv;
 358
 359         out_arg += chunk;
 360         in_arg += chunk;
 361         EVP_CIPHER_CTX_set_num(ctx, nbytes);
 362         if (cdata->cword.b.encdec) {
 363             cdata->cword.b.encdec = 0;
 364             padlock_reload_key();
 365             padlock_aes_block(ivp, ivp, cdata);
 366             cdata->cword.b.encdec = 1;
 367             padlock_reload_key();
 368             while (nbytes) {
 369                 unsigned char c = *(in_arg++);
 370                 *(out_arg++) = c ^ *ivp;
 371                 *(ivp++) = c, nbytes--;
 372             }
 373         } else {
 374             padlock_reload_key();
 375             padlock_aes_block(ivp, ivp, cdata);
 376             padlock_reload_key();
 377             while (nbytes) {
 378                 *ivp = *(out_arg++) = *(in_arg++) ^ *ivp;
 379                 ivp++, nbytes--;
 380             }
 381         }
 382     }
 383
 384     memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), cdata->iv, AES_BLOCK_SIZE);
 385
 386     return 1;
 387 }
 388
 389 static int
 390 padlock_ofb_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
 391                    const unsigned char *in_arg, size_t nbytes)
 392 {
 393     struct padlock_cipher_data *cdata = ALIGNED_CIPHER_DATA(ctx);
 394     size_t chunk;
 395
 396     /*
 397      * ctx->num is maintained in byte-oriented modes, such as CFB and OFB...
 398      */
 399     if ((chunk = EVP_CIPHER_CTX_num(ctx))) {   /* borrow chunk variable */
 400         unsigned char *ivp = EVP_CIPHER_CTX_iv_noconst(ctx);
 401
 402         if (chunk >= AES_BLOCK_SIZE)
 403             return 0;           /* bogus value */
 404
 405         while (chunk < AES_BLOCK_SIZE && nbytes != 0) {
 406             *(out_arg++) = *(in_arg++) ^ ivp[chunk];
 407             chunk++, nbytes--;
 408         }
 409
 410         EVP_CIPHER_CTX_set_num(ctx, chunk % AES_BLOCK_SIZE);
 411     }
 412
 413     if (nbytes == 0)
 414         return 1;
 415
 416     memcpy(cdata->iv, EVP_CIPHER_CTX_iv(ctx), AES_BLOCK_SIZE);
 417
 418     if ((chunk = nbytes & ~(AES_BLOCK_SIZE - 1))) {
 419         if (!padlock_ofb_encrypt(out_arg, in_arg, cdata, chunk))
 420             return 0;
 421         nbytes -= chunk;
 422     }
 423
 424     if (nbytes) {
 425         unsigned char *ivp = cdata->iv;
 426
 427         out_arg += chunk;
 428         in_arg += chunk;
 429         EVP_CIPHER_CTX_set_num(ctx, nbytes);
 430         padlock_reload_key();   /* empirically found */
 431         padlock_aes_block(ivp, ivp, cdata);
 432         padlock_reload_key();   /* empirically found */
 433         while (nbytes) {
 434             *(out_arg++) = *(in_arg++) ^ *ivp;
 435             ivp++, nbytes--;
 436         }
 437     }
 438
 439     memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), cdata->iv, AES_BLOCK_SIZE);
 440
 441     return 1;
 442 }
 443
 444 static void padlock_ctr32_encrypt_glue(const unsigned char *in,
 445                                        unsigned char *out, size_t blocks,
 446                                        struct padlock_cipher_data *ctx,
 447                                        const unsigned char *ivec)
 448 {
 449     memcpy(ctx->iv, ivec, AES_BLOCK_SIZE);
 450     padlock_ctr32_encrypt(out, in, ctx, AES_BLOCK_SIZE * blocks);
 451 }
 452
 453 static int
 454 padlock_ctr_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
 455                    const unsigned char *in_arg, size_t nbytes)
 456 {
 457     struct padlock_cipher_data *cdata = ALIGNED_CIPHER_DATA(ctx);
 458     unsigned int num = EVP_CIPHER_CTX_num(ctx);
 459
 460     CRYPTO_ctr128_encrypt_ctr32(in_arg, out_arg, nbytes,
 461                                 cdata, EVP_CIPHER_CTX_iv_noconst(ctx),
 462                                 EVP_CIPHER_CTX_buf_noconst(ctx), &num,
 463                                 (ctr128_f) padlock_ctr32_encrypt_glue);
 464
 465     EVP_CIPHER_CTX_set_num(ctx, (size_t)num);
 466     return 1;
 467 }
 468
 469 #   define EVP_CIPHER_block_size_ECB       AES_BLOCK_SIZE
 470 #   define EVP_CIPHER_block_size_CBC       AES_BLOCK_SIZE
 471 #   define EVP_CIPHER_block_size_OFB       1
 472 #   define EVP_CIPHER_block_size_CFB       1
 473 #   define EVP_CIPHER_block_size_CTR       1
 474
 475 /*
 476  * Declaring so many ciphers by hand would be a pain. Instead introduce a bit
 477  * of preprocessor magic :-)
 478  */
 479 #   define DECLARE_AES_EVP(ksize,lmode,umode)      \
 480 static EVP_CIPHER *_hidden_aes_##ksize##_##lmode = NULL; \
 481 static const EVP_CIPHER *padlock_aes_##ksize##_##lmode(void) \
 482 {                                                                       \
 483     if (_hidden_aes_##ksize##_##lmode == NULL                           \
 484         && ((_hidden_aes_##ksize##_##lmode =                            \
 485              EVP_CIPHER_meth_new(NID_aes_##ksize##_##lmode,             \
 486                                  EVP_CIPHER_block_size_##umode,         \
 487                                  AES_KEY_SIZE_##ksize)) == NULL         \
 488             || !EVP_CIPHER_meth_set_iv_length(_hidden_aes_##ksize##_##lmode, \
 489                                               AES_BLOCK_SIZE)           \
 490             || !EVP_CIPHER_meth_set_flags(_hidden_aes_##ksize##_##lmode, \
 491                                           0 | EVP_CIPH_##umode##_MODE)  \
 492             || !EVP_CIPHER_meth_set_init(_hidden_aes_##ksize##_##lmode, \
 493                                          padlock_aes_init_key)          \
 494             || !EVP_CIPHER_meth_set_do_cipher(_hidden_aes_##ksize##_##lmode, \
 495                                               padlock_##lmode##_cipher) \
 496             || !EVP_CIPHER_meth_set_impl_ctx_size(_hidden_aes_##ksize##_##lmode, \
 497                                                   sizeof(struct padlock_cipher_data) + 16) \
 498             || !EVP_CIPHER_meth_set_set_asn1_params(_hidden_aes_##ksize##_##lmode, \
 499                                                     EVP_CIPHER_set_asn1_iv) \
 500             || !EVP_CIPHER_meth_set_get_asn1_params(_hidden_aes_##ksize##_##lmode, \
 501                                                     EVP_CIPHER_get_asn1_iv))) { \
 502         EVP_CIPHER_meth_free(_hidden_aes_##ksize##_##lmode);            \
 503         _hidden_aes_##ksize##_##lmode = NULL;                           \
 504     }                                                                   \
 505     return _hidden_aes_##ksize##_##lmode;                               \
 506 }
 507
 508 DECLARE_AES_EVP(128, ecb, ECB)
 509 DECLARE_AES_EVP(128, cbc, CBC)
 510 DECLARE_AES_EVP(128, cfb, CFB)
 511 DECLARE_AES_EVP(128, ofb, OFB)
 512 DECLARE_AES_EVP(128, ctr, CTR)
 513
 514 DECLARE_AES_EVP(192, ecb, ECB)
 515 DECLARE_AES_EVP(192, cbc, CBC)
 516 DECLARE_AES_EVP(192, cfb, CFB)
 517 DECLARE_AES_EVP(192, ofb, OFB)
 518 DECLARE_AES_EVP(192, ctr, CTR)
 519
 520 DECLARE_AES_EVP(256, ecb, ECB)
 521 DECLARE_AES_EVP(256, cbc, CBC)
 522 DECLARE_AES_EVP(256, cfb, CFB)
 523 DECLARE_AES_EVP(256, ofb, OFB)
 524 DECLARE_AES_EVP(256, ctr, CTR)
 525
 526 static int
 527 padlock_ciphers(ENGINE *e, const EVP_CIPHER **cipher, const int **nids,
 528                 int nid)
 529 {
 530     /* No specific cipher => return a list of supported nids ... */
 531     if (!cipher) {
 532         *nids = padlock_cipher_nids;
 533         return padlock_cipher_nids_num;
 534     }
 535
 536     /* ... or the requested "cipher" otherwise */
 537     switch (nid) {
 538     case NID_aes_128_ecb:
 539         *cipher = padlock_aes_128_ecb();
 540         break;
 541     case NID_aes_128_cbc:
 542         *cipher = padlock_aes_128_cbc();
 543         break;
 544     case NID_aes_128_cfb:
 545         *cipher = padlock_aes_128_cfb();
 546         break;
 547     case NID_aes_128_ofb:
 548         *cipher = padlock_aes_128_ofb();
 549         break;
 550     case NID_aes_128_ctr:
 551         *cipher = padlock_aes_128_ctr();
 552         break;
 553
 554     case NID_aes_192_ecb:
 555         *cipher = padlock_aes_192_ecb();
 556         break;
 557     case NID_aes_192_cbc:
 558         *cipher = padlock_aes_192_cbc();
 559         break;
 560     case NID_aes_192_cfb:
 561         *cipher = padlock_aes_192_cfb();
 562         break;
 563     case NID_aes_192_ofb:
 564         *cipher = padlock_aes_192_ofb();
 565         break;
 566     case NID_aes_192_ctr:
 567         *cipher = padlock_aes_192_ctr();
 568         break;
 569
 570     case NID_aes_256_ecb:
 571         *cipher = padlock_aes_256_ecb();
 572         break;
 573     case NID_aes_256_cbc:
 574         *cipher = padlock_aes_256_cbc();
 575         break;
 576     case NID_aes_256_cfb:
 577         *cipher = padlock_aes_256_cfb();
 578         break;
 579     case NID_aes_256_ofb:
 580         *cipher = padlock_aes_256_ofb();
 581         break;
 582     case NID_aes_256_ctr:
 583         *cipher = padlock_aes_256_ctr();
 584         break;
 585
 586     default:
 587         /* Sorry, we don't support this NID */
 588         *cipher = NULL;
 589         return 0;
 590     }
 591
 592     return 1;
 593 }
 594
 595 /* Prepare the encryption key for PadLock usage */
 596 static int
 597 padlock_aes_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,
 598                      const unsigned char *iv, int enc)
 599 {
 600     struct padlock_cipher_data *cdata;
 601     int key_len = EVP_CIPHER_CTX_key_length(ctx) * 8;
 602     unsigned long mode = EVP_CIPHER_CTX_mode(ctx);
 603
 604     if (key == NULL)
 605         return 0;               /* ERROR */
 606
 607     cdata = ALIGNED_CIPHER_DATA(ctx);
 608     memset(cdata, 0, sizeof(*cdata));
 609
 610     /* Prepare Control word. */
 611     if (mode == EVP_CIPH_OFB_MODE || mode == EVP_CIPH_CTR_MODE)
 612         cdata->cword.b.encdec = 0;
 613     else
 614         cdata->cword.b.encdec = (EVP_CIPHER_CTX_encrypting(ctx) == 0);
 615     cdata->cword.b.rounds = 10 + (key_len - 128) / 32;
 616     cdata->cword.b.ksize = (key_len - 128) / 64;
 617
 618     switch (key_len) {
 619     case 128:
 620         /*
 621          * PadLock can generate an extended key for AES128 in hardware
 622          */
 623         memcpy(cdata->ks.rd_key, key, AES_KEY_SIZE_128);
 624         cdata->cword.b.keygen = 0;
 625         break;
 626
 627     case 192:
 628     case 256:
 629         /*
 630          * Generate an extended AES key in software. Needed for AES192/AES256
 631          */
 632         /*
 633          * Well, the above applies to Stepping 8 CPUs and is listed as
 634          * hardware errata. They most likely will fix it at some point and
 635          * then a check for stepping would be due here.
 636          */
 637         if ((mode == EVP_CIPH_ECB_MODE || mode == EVP_CIPH_CBC_MODE)
 638             && !enc)
 639             AES_set_decrypt_key(key, key_len, &cdata->ks);
 640         else
 641             AES_set_encrypt_key(key, key_len, &cdata->ks);
 642 #   ifndef AES_ASM
 643         /*
 644          * OpenSSL C functions use byte-swapped extended key.
 645          */
 646         padlock_key_bswap(&cdata->ks);
 647 #   endif
 648         cdata->cword.b.keygen = 1;
 649         break;
 650
 651     default:
 652         /* ERROR */
 653         return 0;
 654     }
 655
 656     /*
 657      * This is done to cover for cases when user reuses the
 658      * context for new key. The catch is that if we don't do
 659      * this, padlock_eas_cipher might proceed with old key...
 660      */
 661     padlock_reload_key();
 662
 663     return 1;
 664 }
 665
 666 /* ===== Random Number Generator ===== */
 667 /*
 668  * This code is not engaged. The reason is that it does not comply
 669  * with recommendations for VIA RNG usage for secure applications
 670  * (posted at http://www.via.com.tw/en/viac3/c3.jsp) nor does it
 671  * provide meaningful error control...
 672  */
 673 /*
 674  * Wrapper that provides an interface between the API and the raw PadLock
 675  * RNG
 676  */
 677 static int padlock_rand_bytes(unsigned char *output, int count)
 678 {
 679     unsigned int eax, buf;
 680
 681     while (count >= 8) {
 682         eax = padlock_xstore(output, 0);
 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) != 8)
 691             return 0;           /* fatal failure...  */
 692         output += 8;
 693         count -= 8;
 694     }
 695     while (count > 0) {
 696         eax = padlock_xstore(&buf, 3);
 697         if (!(eax & (1 << 6)))
 698             return 0;           /* RNG disabled */
 699         /* this ---vv--- covers DC bias, Raw Bits and String Filter */
 700         if (eax & (0x1F << 10))
 701             return 0;
 702         if ((eax & 0x1F) == 0)
 703             continue;           /* no data, retry... */
 704         if ((eax & 0x1F) != 1)
 705             return 0;           /* fatal failure...  */
 706         *output++ = (unsigned char)buf;
 707         count--;
 708     }
 709     OPENSSL_cleanse(&buf, sizeof(buf));
 710
 711     return 1;
 712 }
 713
 714 /* Dummy but necessary function */
 715 static int padlock_rand_status(void)
 716 {
 717     return 1;
 718 }
 719
 720 /* Prepare structure for registration */
 721 static RAND_METHOD padlock_rand = {
 722     NULL,                       /* seed */
 723     padlock_rand_bytes,         /* bytes */
 724     NULL,                       /* cleanup */
 725     NULL,                       /* add */
 726     padlock_rand_bytes,         /* pseudorand */
 727     padlock_rand_status,        /* rand status */
 728 };
 729
 730 #  endif                        /* COMPILE_HW_PADLOCK */
 731 # endif                         /* !OPENSSL_NO_HW_PADLOCK */
 732 #endif                          /* !OPENSSL_NO_HW */
 733
 734 #if defined(OPENSSL_NO_HW) || defined(OPENSSL_NO_HW_PADLOCK) \
 735         || !defined(COMPILE_HW_PADLOCK)
 736 # ifndef OPENSSL_NO_DYNAMIC_ENGINE
 737 OPENSSL_EXPORT
 738     int bind_engine(ENGINE *e, const char *id, const dynamic_fns *fns);
 739 OPENSSL_EXPORT
 740     int bind_engine(ENGINE *e, const char *id, const dynamic_fns *fns)
 741 {
 742     return 0;
 743 }
 744
 745 IMPLEMENT_DYNAMIC_CHECK_FN()
 746 # endif
 747 #endif