text: /*
   * Copyright 2004-2019 The OpenSSL Project Authors. All Rights Reserved.
   *
   * Licensed under the OpenSSL license (the "License").  You may not use
   * this file except in compliance with the License.  You can obtain a copy
   * in the file LICENSE in the source distribution or at
   * https://www.openssl.org/source/license.html
   */
  
  #include <stdio.h>
  #include <string.h>
  
  #include <openssl/opensslconf.h>
  #include <openssl/crypto.h>
  #include <openssl/engine.h>
  #include <openssl/evp.h>
  #include <openssl/aes.h>
  #include <openssl/rand.h>
  #include <openssl/err.h>
  #include <openssl/modes.h>
  
  #ifndef OPENSSL_NO_HW
  # ifndef OPENSSL_NO_HW_PADLOCK
  
  /* Attempt to have a single source for both 0.9.7 and 0.9.8 :-) */
  #  if (OPENSSL_VERSION_NUMBER >= 0x00908000L)
  #   ifndef OPENSSL_NO_DYNAMIC_ENGINE
  #    define DYNAMIC_ENGINE
  #   endif
  #  elif (OPENSSL_VERSION_NUMBER >= 0x00907000L)
  #   ifdef ENGINE_DYNAMIC_SUPPORT
  #    define DYNAMIC_ENGINE
  #   endif
  #  else
  #   error "Only OpenSSL >= 0.9.7 is supported"
  #  endif
  
  /*
   * VIA PadLock AES is available *ONLY* on some x86 CPUs. Not only that it
   * doesn't exist elsewhere, but it even can't be compiled on other platforms!
   */
  
  #  undef COMPILE_HW_PADLOCK
  #  if defined(PADLOCK_ASM)
  #   define COMPILE_HW_PADLOCK
  #   ifdef OPENSSL_NO_DYNAMIC_ENGINE
  static ENGINE *ENGINE_padlock(void);
  #   endif
  #  endif
  
  #  ifdef OPENSSL_NO_DYNAMIC_ENGINE
  void engine_load_padlock_int(void);
  void engine_load_padlock_int(void)
  {
  /* On non-x86 CPUs it just returns. */
  #   ifdef COMPILE_HW_PADLOCK
      ENGINE *toadd = ENGINE_padlock();
      if (!toadd)
          return;
      ENGINE_add(toadd);
      ENGINE_free(toadd);
      ERR_clear_error();
  #   endif
  }
  
  #  endif
  
  #  ifdef COMPILE_HW_PADLOCK
  
  /* Function for ENGINE detection and control */
  static int padlock_available(void);
  static int padlock_init(ENGINE *e);
  
  /* RNG Stuff */
  static RAND_METHOD padlock_rand;
  
  /* Cipher Stuff */
  static int padlock_ciphers(ENGINE *e, const EVP_CIPHER **cipher,
                             const int **nids, int nid);
  
  /* Engine names */
  static const char *padlock_id = "padlock";
  static char padlock_name[100];
  
  /* Available features */
  static int padlock_use_ace = 0; /* Advanced Cryptography Engine */
  static int padlock_use_rng = 0; /* Random Number Generator */
  
  /* ===== Engine "management" functions ===== */
  
  /* Prepare the ENGINE structure for registration */
  static int padlock_bind_helper(ENGINE *e)
  {
      /* Check available features */
      padlock_available();
  
      /*
       * RNG is currently disabled for reasons discussed in commentary just
       * before padlock_rand_bytes function.
       */
      padlock_use_rng = 0;
  
      /* Generate a nice engine name with available features */
      BIO_snprintf(padlock_name, sizeof(padlock_name),
                   "VIA PadLock (%s, %s)",
                   padlock_use_rng ? "RNG" : "no-RNG",
                   padlock_use_ace ? "ACE" : "no-ACE");
  
      /* Register everything or return with an error */
      if (!ENGINE_set_id(e, padlock_id) ||
          !ENGINE_set_name(e, padlock_name) ||
          !ENGINE_set_init_function(e, padlock_init) ||
          (padlock_use_ace && !ENGINE_set_ciphers(e, padlock_ciphers)) ||
          (padlock_use_rng && !ENGINE_set_RAND(e, &padlock_rand))) {
          return 0;
      }
  
      /* Everything looks good */
      return 1;
  }
  
  #   ifdef OPENSSL_NO_DYNAMIC_ENGINE
  /* Constructor */
  static ENGINE *ENGINE_padlock(void)
  {
      ENGINE *eng = ENGINE_new();
  
      if (eng == NULL) {
          return NULL;
      }
  
      if (!padlock_bind_helper(eng)) {
          ENGINE_free(eng);
          return NULL;
      }
  
      return eng;
  }
  #   endif
  
  /* Check availability of the engine */
  static int padlock_init(ENGINE *e)
  {
      return (padlock_use_rng || padlock_use_ace);
  }
  
  /*
   * This stuff is needed if this ENGINE is being compiled into a
   * self-contained shared-library.
   */
  #   ifndef OPENSSL_NO_DYNAMIC_ENGINE
  static int padlock_bind_fn(ENGINE *e, const char *id)
  {
      if (id && (strcmp(id, padlock_id) != 0)) {
          return 0;
      }
  
      if (!padlock_bind_helper(e)) {
          return 0;
      }
  
      return 1;
  }
  
  IMPLEMENT_DYNAMIC_CHECK_FN()
  IMPLEMENT_DYNAMIC_BIND_FN(padlock_bind_fn)
  #   endif                       /* !OPENSSL_NO_DYNAMIC_ENGINE */
  /* ===== Here comes the "real" engine ===== */
  
  /* Some AES-related constants */
  #   define AES_BLOCK_SIZE          16
  #   define AES_KEY_SIZE_128        16
  #   define AES_KEY_SIZE_192        24
  #   define AES_KEY_SIZE_256        32
      /*
       * Here we store the status information relevant to the current context.
       */
      /*
       * BIG FAT WARNING: Inline assembler in PADLOCK_XCRYPT_ASM() depends on
       * the order of items in this structure.  Don't blindly modify, reorder,
       * etc!
       */
  struct padlock_cipher_data {
      unsigned char iv[AES_BLOCK_SIZE]; /* Initialization vector */
      union {
          unsigned int pad[4];
          struct {
              int rounds:4;
              int dgst:1;         /* n/a in C3 */
              int align:1;        /* n/a in C3 */
              int ciphr:1;        /* n/a in C3 */
              unsigned int keygen:1;
              int interm:1;
              unsigned int encdec:1;
              int ksize:2;
          } b;
      } cword;                    /* Control word */
      AES_KEY ks;                 /* Encryption key */
  };
  
  /* Interface to assembler module */
  unsigned int padlock_capability(void);
  void padlock_key_bswap(AES_KEY *key);
  void padlock_verify_context(struct padlock_cipher_data *ctx);
  void padlock_reload_key(void);
  void padlock_aes_block(void *out, const void *inp,
                         struct padlock_cipher_data *ctx);
  int padlock_ecb_encrypt(void *out, const void *inp,
                          struct padlock_cipher_data *ctx, size_t len);
  int padlock_cbc_encrypt(void *out, const void *inp,
                          struct padlock_cipher_data *ctx, size_t len);
  int padlock_cfb_encrypt(void *out, const void *inp,
                          struct padlock_cipher_data *ctx, size_t len);
  int padlock_ofb_encrypt(void *out, const void *inp,
                          struct padlock_cipher_data *ctx, size_t len);
  int padlock_ctr32_encrypt(void *out, const void *inp,
                            struct padlock_cipher_data *ctx, size_t len);
  int padlock_xstore(void *out, int edx);
  void padlock_sha1_oneshot(void *ctx, const void *inp, size_t len);
  void padlock_sha1(void *ctx, const void *inp, size_t len);
  void padlock_sha256_oneshot(void *ctx, const void *inp, size_t len);
  void padlock_sha256(void *ctx, const void *inp, size_t len);
  
  /*
   * Load supported features of the CPU to see if the PadLock is available.
   */
  static int padlock_available(void)
  {
      unsigned int edx = padlock_capability();
  
      /* Fill up some flags */
      padlock_use_ace = ((edx & (0x3 << 6)) == (0x3 << 6));
      padlock_use_rng = ((edx & (0x3 << 2)) == (0x3 << 2));
  
      return padlock_use_ace + padlock_use_rng;
  }
  
  /* ===== AES encryption/decryption ===== */
  
  #   if defined(NID_aes_128_cfb128) && ! defined (NID_aes_128_cfb)
  #    define NID_aes_128_cfb NID_aes_128_cfb128
  #   endif
  
  #   if defined(NID_aes_128_ofb128) && ! defined (NID_aes_128_ofb)
  #    define NID_aes_128_ofb NID_aes_128_ofb128
  #   endif
  
  #   if defined(NID_aes_192_cfb128) && ! defined (NID_aes_192_cfb)
  #    define NID_aes_192_cfb NID_aes_192_cfb128
  #   endif
  
  #   if defined(NID_aes_192_ofb128) && ! defined (NID_aes_192_ofb)
  #    define NID_aes_192_ofb NID_aes_192_ofb128
  #   endif
  
  #   if defined(NID_aes_256_cfb128) && ! defined (NID_aes_256_cfb)
  #    define NID_aes_256_cfb NID_aes_256_cfb128
  #   endif
  
  #   if defined(NID_aes_256_ofb128) && ! defined (NID_aes_256_ofb)
  #    define NID_aes_256_ofb NID_aes_256_ofb128
  #   endif
  
  /* List of supported ciphers. */
  static const int padlock_cipher_nids[] = {
      NID_aes_128_ecb,
      NID_aes_128_cbc,
      NID_aes_128_cfb,
      NID_aes_128_ofb,
      NID_aes_128_ctr,
  
      NID_aes_192_ecb,
      NID_aes_192_cbc,
      NID_aes_192_cfb,
      NID_aes_192_ofb,
      NID_aes_192_ctr,
  
      NID_aes_256_ecb,
      NID_aes_256_cbc,
      NID_aes_256_cfb,
      NID_aes_256_ofb,
      NID_aes_256_ctr
  };
  
  static int padlock_cipher_nids_num = (sizeof(padlock_cipher_nids) /
                                        sizeof(padlock_cipher_nids[0]));
  
  /* Function prototypes ... */
  static int padlock_aes_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,
                                  const unsigned char *iv, int enc);
  
  #   define NEAREST_ALIGNED(ptr) ( (unsigned char *)(ptr) +         \
          ( (0x10 - ((size_t)(ptr) & 0x0F)) & 0x0F )      )
  #   define ALIGNED_CIPHER_DATA(ctx) ((struct padlock_cipher_data *)\
          NEAREST_ALIGNED(EVP_CIPHER_CTX_get_cipher_data(ctx)))
  
  static int
  padlock_ecb_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
                     const unsigned char *in_arg, size_t nbytes)
  {
      return padlock_ecb_encrypt(out_arg, in_arg,
                                 ALIGNED_CIPHER_DATA(ctx), nbytes);
  }
  
  static int
  padlock_cbc_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
                     const unsigned char *in_arg, size_t nbytes)
  {
      struct padlock_cipher_data *cdata = ALIGNED_CIPHER_DATA(ctx);
      int ret;
  
      memcpy(cdata->iv, EVP_CIPHER_CTX_iv(ctx), AES_BLOCK_SIZE);
      if ((ret = padlock_cbc_encrypt(out_arg, in_arg, cdata, nbytes)))
          memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), cdata->iv, AES_BLOCK_SIZE);
      return ret;
  }
  
  static int
  padlock_cfb_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
                     const unsigned char *in_arg, size_t nbytes)
  {
      struct padlock_cipher_data *cdata = ALIGNED_CIPHER_DATA(ctx);
      size_t chunk;
  
      if ((chunk = EVP_CIPHER_CTX_num(ctx))) {   /* borrow chunk variable */
          unsigned char *ivp = EVP_CIPHER_CTX_iv_noconst(ctx);
  
          if (chunk >= AES_BLOCK_SIZE)
              return 0;           /* bogus value */
  
          if (EVP_CIPHER_CTX_encrypting(ctx))
              while (chunk < AES_BLOCK_SIZE && nbytes != 0) {
                  ivp[chunk] = *(out_arg++) = *(in_arg++) ^ ivp[chunk];
                  chunk++, nbytes--;
          } else
              while (chunk < AES_BLOCK_SIZE && nbytes != 0) {
                  unsigned char c = *(in_arg++);
                  *(out_arg++) = c ^ ivp[chunk];
                  ivp[chunk++] = c, nbytes--;
              }
  
          EVP_CIPHER_CTX_set_num(ctx, chunk % AES_BLOCK_SIZE);
      }
  
      if (nbytes == 0)
          return 1;
  
      memcpy(cdata->iv, EVP_CIPHER_CTX_iv(ctx), AES_BLOCK_SIZE);
  
      if ((chunk = nbytes & ~(AES_BLOCK_SIZE - 1))) {
          if (!padlock_cfb_encrypt(out_arg, in_arg, cdata, chunk))
              return 0;
          nbytes -= chunk;
      }
  
      if (nbytes) {
          unsigned char *ivp = cdata->iv;
  
          out_arg += chunk;
          in_arg += chunk;
          EVP_CIPHER_CTX_set_num(ctx, nbytes);
          if (cdata->cword.b.encdec) {
              cdata->cword.b.encdec = 0;
              padlock_reload_key();
              padlock_aes_block(ivp, ivp, cdata);
              cdata->cword.b.encdec = 1;
              padlock_reload_key();
              while (nbytes) {
                  unsigned char c = *(in_arg++);
                  *(out_arg++) = c ^ *ivp;
                  *(ivp++) = c, nbytes--;
              }
          } else {
              padlock_reload_key();
              padlock_aes_block(ivp, ivp, cdata);
              padlock_reload_key();
              while (nbytes) {
                  *ivp = *(out_arg++) = *(in_arg++) ^ *ivp;
                  ivp++, nbytes--;
              }
          }
      }
  
      memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), cdata->iv, AES_BLOCK_SIZE);
  
      return 1;
  }
  
  static int
  padlock_ofb_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
                     const unsigned char *in_arg, size_t nbytes)
  {
      struct padlock_cipher_data *cdata = ALIGNED_CIPHER_DATA(ctx);
      size_t chunk;
  
      /*
       * ctx->num is maintained in byte-oriented modes, such as CFB and OFB...
       */
      if ((chunk = EVP_CIPHER_CTX_num(ctx))) {   /* borrow chunk variable */
          unsigned char *ivp = EVP_CIPHER_CTX_iv_noconst(ctx);
  
          if (chunk >= AES_BLOCK_SIZE)
              return 0;           /* bogus value */
  
          while (chunk < AES_BLOCK_SIZE && nbytes != 0) {
              *(out_arg++) = *(in_arg++) ^ ivp[chunk];
              chunk++, nbytes--;
          }
  
          EVP_CIPHER_CTX_set_num(ctx, chunk % AES_BLOCK_SIZE);
      }
  
      if (nbytes == 0)
          return 1;
  
      memcpy(cdata->iv, EVP_CIPHER_CTX_iv(ctx), AES_BLOCK_SIZE);
  
      if ((chunk = nbytes & ~(AES_BLOCK_SIZE - 1))) {
          if (!padlock_ofb_encrypt(out_arg, in_arg, cdata, chunk))
              return 0;
          nbytes -= chunk;
      }
  
      if (nbytes) {
          unsigned char *ivp = cdata->iv;
  
          out_arg += chunk;
          in_arg += chunk;
          EVP_CIPHER_CTX_set_num(ctx, nbytes);
          padlock_reload_key();   /* empirically found */
          padlock_aes_block(ivp, ivp, cdata);
          padlock_reload_key();   /* empirically found */
          while (nbytes) {
              *(out_arg++) = *(in_arg++) ^ *ivp;
              ivp++, nbytes--;
          }
      }
  
      memcpy(EVP_CIPHER_CTX_iv_noconst(ctx), cdata->iv, AES_BLOCK_SIZE);
  
      return 1;
  }
  
  static void padlock_ctr32_encrypt_glue(const unsigned char *in,
                                         unsigned char *out, size_t blocks,
                                         struct padlock_cipher_data *ctx,
                                         const unsigned char *ivec)
  {
      memcpy(ctx->iv, ivec, AES_BLOCK_SIZE);
      padlock_ctr32_encrypt(out, in, ctx, AES_BLOCK_SIZE * blocks);
  }
  
  static int
  padlock_ctr_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out_arg,
                     const unsigned char *in_arg, size_t nbytes)
  {
      struct padlock_cipher_data *cdata = ALIGNED_CIPHER_DATA(ctx);
      unsigned int num = EVP_CIPHER_CTX_num(ctx);
  
      CRYPTO_ctr128_encrypt_ctr32(in_arg, out_arg, nbytes,
                                  cdata, EVP_CIPHER_CTX_iv_noconst(ctx),
                                  EVP_CIPHER_CTX_buf_noconst(ctx), &num,
                                  (ctr128_f) padlock_ctr32_encrypt_glue);
  
      EVP_CIPHER_CTX_set_num(ctx, (size_t)num);
      return 1;
  }
  
  #   define EVP_CIPHER_block_size_ECB       AES_BLOCK_SIZE
  #   define EVP_CIPHER_block_size_CBC       AES_BLOCK_SIZE
  #   define EVP_CIPHER_block_size_OFB       1
  #   define EVP_CIPHER_block_size_CFB       1
  #   define EVP_CIPHER_block_size_CTR       1
  
  /*
   * Declaring so many ciphers by hand would be a pain. Instead introduce a bit
   * of preprocessor magic :-)
   */
  #   define DECLARE_AES_EVP(ksize,lmode,umode)      \
  static EVP_CIPHER *_hidden_aes_##ksize##_##lmode = NULL; \
  static const EVP_CIPHER *padlock_aes_##ksize##_##lmode(void) \
  {                                                                       \
      if (_hidden_aes_##ksize##_##lmode == NULL                           \
          && ((_hidden_aes_##ksize##_##lmode =                            \
               EVP_CIPHER_meth_new(NID_aes_##ksize##_##lmode,             \
                                   EVP_CIPHER_block_size_##umode,         \
                                   AES_KEY_SIZE_##ksize)) == NULL         \
              || !EVP_CIPHER_meth_set_iv_length(_hidden_aes_##ksize##_##lmode, \
                                                AES_BLOCK_SIZE)           \
              || !EVP_CIPHER_meth_set_flags(_hidden_aes_##ksize##_##lmode, \
                                            0 | EVP_CIPH_##umode##_MODE)  \
              || !EVP_CIPHER_meth_set_init(_hidden_aes_##ksize##_##lmode, \
                                           padlock_aes_init_key)          \
              || !EVP_CIPHER_meth_set_do_cipher(_hidden_aes_##ksize##_##lmode, \
                                                padlock_##lmode##_cipher) \
              || !EVP_CIPHER_meth_set_impl_ctx_size(_hidden_aes_##ksize##_##lmode, \
                                                    sizeof(struct padlock_cipher_data) + 16) \
              || !EVP_CIPHER_meth_set_set_asn1_params(_hidden_aes_##ksize##_##lmode, \
                                                      EVP_CIPHER_set_asn1_iv) \
              || !EVP_CIPHER_meth_set_get_asn1_params(_hidden_aes_##ksize##_##lmode, \
                                                      EVP_CIPHER_get_asn1_iv))) { \
          EVP_CIPHER_meth_free(_hidden_aes_##ksize##_##lmode);            \
          _hidden_aes_##ksize##_##lmode = NULL;                           \
      }                                                                   \
      return _hidden_aes_##ksize##_##lmode;                               \
  }
  
  DECLARE_AES_EVP(128, ecb, ECB)
  DECLARE_AES_EVP(128, cbc, CBC)
  DECLARE_AES_EVP(128, cfb, CFB)
  DECLARE_AES_EVP(128, ofb, OFB)
  DECLARE_AES_EVP(128, ctr, CTR)
  
  DECLARE_AES_EVP(192, ecb, ECB)
  DECLARE_AES_EVP(192, cbc, CBC)
  DECLARE_AES_EVP(192, cfb, CFB)
  DECLARE_AES_EVP(192, ofb, OFB)
  DECLARE_AES_EVP(192, ctr, CTR)
  
  DECLARE_AES_EVP(256, ecb, ECB)
  DECLARE_AES_EVP(256, cbc, CBC)
  DECLARE_AES_EVP(256, cfb, CFB)
  DECLARE_AES_EVP(256, ofb, OFB)
  DECLARE_AES_EVP(256, ctr, CTR)
  
  static int
  padlock_ciphers(ENGINE *e, const EVP_CIPHER **cipher, const int **nids,
                  int nid)
  {
      /* No specific cipher => return a list of supported nids ... */
      if (!cipher) {
          *nids = padlock_cipher_nids;
          return padlock_cipher_nids_num;
      }
  
      /* ... or the requested "cipher" otherwise */
      switch (nid) {
      case NID_aes_128_ecb:
          *cipher = padlock_aes_128_ecb();
          break;
      case NID_aes_128_cbc:
          *cipher = padlock_aes_128_cbc();
          break;
      case NID_aes_128_cfb:
          *cipher = padlock_aes_128_cfb();
          break;
      case NID_aes_128_ofb:
          *cipher = padlock_aes_128_ofb();
          break;
      case NID_aes_128_ctr:
          *cipher = padlock_aes_128_ctr();
          break;
  
      case NID_aes_192_ecb:
          *cipher = padlock_aes_192_ecb();
          break;
      case NID_aes_192_cbc:
          *cipher = padlock_aes_192_cbc();
          break;
      case NID_aes_192_cfb:
          *cipher = padlock_aes_192_cfb();
          break;
      case NID_aes_192_ofb:
          *cipher = padlock_aes_192_ofb();
          break;
      case NID_aes_192_ctr:
          *cipher = padlock_aes_192_ctr();
          break;
  
      case NID_aes_256_ecb:
          *cipher = padlock_aes_256_ecb();
          break;
      case NID_aes_256_cbc:
          *cipher = padlock_aes_256_cbc();
          break;
      case NID_aes_256_cfb:
          *cipher = padlock_aes_256_cfb();
          break;
      case NID_aes_256_ofb:
          *cipher = padlock_aes_256_ofb();
          break;
      case NID_aes_256_ctr:
          *cipher = padlock_aes_256_ctr();
          break;
  
      default:
          /* Sorry, we don't support this NID */
          *cipher = NULL;
          return 0;
      }
  
      return 1;
  }
  
  /* Prepare the encryption key for PadLock usage */
  static int
  padlock_aes_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,
                       const unsigned char *iv, int enc)
  {
      struct padlock_cipher_data *cdata;
      int key_len = EVP_CIPHER_CTX_key_length(ctx) * 8;
      unsigned long mode = EVP_CIPHER_CTX_mode(ctx);
  
      if (key == NULL)
          return 0;               /* ERROR */
  
      cdata = ALIGNED_CIPHER_DATA(ctx);
      memset(cdata, 0, sizeof(*cdata));
  
      /* Prepare Control word. */
      if (mode == EVP_CIPH_OFB_MODE || mode == EVP_CIPH_CTR_MODE)
          cdata->cword.b.encdec = 0;
      else
          cdata->cword.b.encdec = (EVP_CIPHER_CTX_encrypting(ctx) == 0);
      cdata->cword.b.rounds = 10 + (key_len - 128) / 32;
      cdata->cword.b.ksize = (key_len - 128) / 64;
  
      switch (key_len) {
      case 128:
          /*
           * PadLock can generate an extended key for AES128 in hardware
           */
          memcpy(cdata->ks.rd_key, key, AES_KEY_SIZE_128);
          cdata->cword.b.keygen = 0;
          break;
  
      case 192:
      case 256:
          /*
           * Generate an extended AES key in software. Needed for AES192/AES256
           */
          /*
           * Well, the above applies to Stepping 8 CPUs and is listed as
           * hardware errata. They most likely will fix it at some point and
           * then a check for stepping would be due here.
           */
          if ((mode == EVP_CIPH_ECB_MODE || mode == EVP_CIPH_CBC_MODE)
              && !enc)
              AES_set_decrypt_key(key, key_len, &cdata->ks);
          else
              AES_set_encrypt_key(key, key_len, &cdata->ks);
  #   ifndef AES_ASM
          /*
           * OpenSSL C functions use byte-swapped extended key.
           */
          padlock_key_bswap(&cdata->ks);
  #   endif
          cdata->cword.b.keygen = 1;
          break;
  
      default:
          /* ERROR */
          return 0;
      }
  
      /*
       * This is done to cover for cases when user reuses the
       * context for new key. The catch is that if we don't do
       * this, padlock_eas_cipher might proceed with old key...
       */
      padlock_reload_key();
  
      return 1;
  }
  
  /* ===== Random Number Generator ===== */
  /*
   * This code is not engaged. The reason is that it does not comply
   * with recommendations for VIA RNG usage for secure applications
   * (posted at http://www.via.com.tw/en/viac3/c3.jsp) nor does it
   * provide meaningful error control...
   */
  /*
   * Wrapper that provides an interface between the API and the raw PadLock
   * RNG
   */
  static int padlock_rand_bytes(unsigned char *output, int count)
  {
      unsigned int eax, buf;
  
      while (count >= 8) {
          eax = padlock_xstore(output, 0);
          if (!(eax & (1 << 6)))
              return 0;           /* RNG disabled */
          /* this ---vv--- covers DC bias, Raw Bits and String Filter */
          if (eax & (0x1F << 10))
              return 0;
          if ((eax & 0x1F) == 0)
              continue;           /* no data, retry... */
          if ((eax & 0x1F) != 8)
              return 0;           /* fatal failure...  */
          output += 8;
          count -= 8;
      }
      while (count > 0) {
          eax = padlock_xstore(&buf, 3);
          if (!(eax & (1 << 6)))
              return 0;           /* RNG disabled */
          /* this ---vv--- covers DC bias, Raw Bits and String Filter */
          if (eax & (0x1F << 10))
              return 0;
          if ((eax & 0x1F) == 0)
              continue;           /* no data, retry... */
          if ((eax & 0x1F) != 1)
              return 0;           /* fatal failure...  */
          *output++ = (unsigned char)buf;
          count--;
      }
      OPENSSL_cleanse(&buf, sizeof(buf));
  
      return 1;
  }
  
  /* Dummy but necessary function */
  static int padlock_rand_status(void)
  {
      return 1;
  }
  
  /* Prepare structure for registration */
  static RAND_METHOD padlock_rand = {
      NULL,                       /* seed */
      padlock_rand_bytes,         /* bytes */
      NULL,                       /* cleanup */
      NULL,                       /* add */
      padlock_rand_bytes,         /* pseudorand */
      padlock_rand_status,        /* rand status */
  };
  
  #  endif                        /* COMPILE_HW_PADLOCK */
  # endif                         /* !OPENSSL_NO_HW_PADLOCK */
  #endif                          /* !OPENSSL_NO_HW */
  
  #if defined(OPENSSL_NO_HW) || defined(OPENSSL_NO_HW_PADLOCK) \
          || !defined(COMPILE_HW_PADLOCK)
  # ifndef OPENSSL_NO_DYNAMIC_ENGINE
  OPENSSL_EXPORT
      int bind_engine(ENGINE *e, const char *id, const dynamic_fns *fns);
  OPENSSL_EXPORT
      int bind_engine(ENGINE *e, const char *id, const dynamic_fns *fns)
  {
      return 0;
  }
  
  IMPLEMENT_DYNAMIC_CHECK_FN()
  # endif
  #endif
  