text: /*
   * Copyright 1995-2018 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 "internal/cryptlib.h"
  
  #ifndef OPENSSL_NO_RC2
  
  # include <openssl/evp.h>
  # include <openssl/objects.h>
  # include "crypto/evp.h"
  # include <openssl/rc2.h>
  
  static int rc2_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,
                          const unsigned char *iv, int enc);
  static int rc2_meth_to_magic(EVP_CIPHER_CTX *ctx);
  static int rc2_magic_to_meth(int i);
  static int rc2_set_asn1_type_and_iv(EVP_CIPHER_CTX *c, ASN1_TYPE *type);
  static int rc2_get_asn1_type_and_iv(EVP_CIPHER_CTX *c, ASN1_TYPE *type);
  static int rc2_ctrl(EVP_CIPHER_CTX *c, int type, int arg, void *ptr);
  
  typedef struct {
      int key_bits;               /* effective key bits */
      RC2_KEY ks;                 /* key schedule */
  } EVP_RC2_KEY;
  
  # define data(ctx)       EVP_C_DATA(EVP_RC2_KEY,ctx)
  
  IMPLEMENT_BLOCK_CIPHER(rc2, ks, RC2, EVP_RC2_KEY, NID_rc2,
                         8,
                         RC2_KEY_LENGTH, 8, 64,
                         EVP_CIPH_VARIABLE_LENGTH | EVP_CIPH_CTRL_INIT,
                         rc2_init_key, NULL,
                         rc2_set_asn1_type_and_iv, rc2_get_asn1_type_and_iv,
                         rc2_ctrl)
  # define RC2_40_MAGIC    0xa0
  # define RC2_64_MAGIC    0x78
  # define RC2_128_MAGIC   0x3a
  static const EVP_CIPHER r2_64_cbc_cipher = {
      NID_rc2_64_cbc,
      8, 8 /* 64 bit */ , 8,
      EVP_CIPH_CBC_MODE | EVP_CIPH_VARIABLE_LENGTH | EVP_CIPH_CTRL_INIT,
      rc2_init_key,
      rc2_cbc_cipher,
      NULL,
      sizeof(EVP_RC2_KEY),
      rc2_set_asn1_type_and_iv,
      rc2_get_asn1_type_and_iv,
      rc2_ctrl,
      NULL
  };
  
  static const EVP_CIPHER r2_40_cbc_cipher = {
      NID_rc2_40_cbc,
      8, 5 /* 40 bit */ , 8,
      EVP_CIPH_CBC_MODE | EVP_CIPH_VARIABLE_LENGTH | EVP_CIPH_CTRL_INIT,
      rc2_init_key,
      rc2_cbc_cipher,
      NULL,
      sizeof(EVP_RC2_KEY),
      rc2_set_asn1_type_and_iv,
      rc2_get_asn1_type_and_iv,
      rc2_ctrl,
      NULL
  };
  
  const EVP_CIPHER *EVP_rc2_64_cbc(void)
  {
      return &r2_64_cbc_cipher;
  }
  
  const EVP_CIPHER *EVP_rc2_40_cbc(void)
  {
      return &r2_40_cbc_cipher;
  }
  
  static int rc2_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,
                          const unsigned char *iv, int enc)
  {
      RC2_set_key(&data(ctx)->ks, EVP_CIPHER_CTX_key_length(ctx),
                  key, data(ctx)->key_bits);
      return 1;
  }
  
  static int rc2_meth_to_magic(EVP_CIPHER_CTX *e)
  {
      int i;
  
      if (EVP_CIPHER_CTX_ctrl(e, EVP_CTRL_GET_RC2_KEY_BITS, 0, &i) <= 0)
          return 0;
      if (i == 128)
          return RC2_128_MAGIC;
      else if (i == 64)
          return RC2_64_MAGIC;
      else if (i == 40)
          return RC2_40_MAGIC;
      else
          return 0;
  }
  
  static int rc2_magic_to_meth(int i)
  {
      if (i == RC2_128_MAGIC)
          return 128;
      else if (i == RC2_64_MAGIC)
          return 64;
      else if (i == RC2_40_MAGIC)
          return 40;
      else {
          EVPerr(EVP_F_RC2_MAGIC_TO_METH, EVP_R_UNSUPPORTED_KEY_SIZE);
          return 0;
      }
  }
  
  static int rc2_get_asn1_type_and_iv(EVP_CIPHER_CTX *c, ASN1_TYPE *type)
  {
      long num = 0;
      int i = 0;
      int key_bits;
      unsigned int l;
      unsigned char iv[EVP_MAX_IV_LENGTH];
  
      if (type != NULL) {
          l = EVP_CIPHER_CTX_iv_length(c);
          OPENSSL_assert(l <= sizeof(iv));
          i = ASN1_TYPE_get_int_octetstring(type, &num, iv, l);
          if (i != (int)l)
              return -1;
          key_bits = rc2_magic_to_meth((int)num);
          if (!key_bits)
              return -1;
          if (i > 0 && !EVP_CipherInit_ex(c, NULL, NULL, NULL, iv, -1))
              return -1;
          if (EVP_CIPHER_CTX_ctrl(c, EVP_CTRL_SET_RC2_KEY_BITS, key_bits,
                                  NULL) <= 0
                  || EVP_CIPHER_CTX_set_key_length(c, key_bits / 8) <= 0)
              return -1;
      }
      return i;
  }
  
  static int rc2_set_asn1_type_and_iv(EVP_CIPHER_CTX *c, ASN1_TYPE *type)
  {
      long num;
      int i = 0, j;
  
      if (type != NULL) {
          num = rc2_meth_to_magic(c);
          j = EVP_CIPHER_CTX_iv_length(c);
          i = ASN1_TYPE_set_int_octetstring(type, num,
                                            (unsigned char *)EVP_CIPHER_CTX_original_iv(c),
                                            j);
      }
      return i;
  }
  
  static int rc2_ctrl(EVP_CIPHER_CTX *c, int type, int arg, void *ptr)
  {
      switch (type) {
      case EVP_CTRL_INIT:
          data(c)->key_bits = EVP_CIPHER_CTX_key_length(c) * 8;
          return 1;
  
      case EVP_CTRL_GET_RC2_KEY_BITS:
          *(int *)ptr = data(c)->key_bits;
          return 1;
  
      case EVP_CTRL_SET_RC2_KEY_BITS:
          if (arg > 0) {
              data(c)->key_bits = arg;
              return 1;
          }
          return 0;
  # ifdef PBE_PRF_TEST
      case EVP_CTRL_PBE_PRF_NID:
          *(int *)ptr = NID_hmacWithMD5;
          return 1;
  # endif
  
      default:
          return -1;
      }
  }
  
  #endif
  