Compartir a través de

2.3.7.3 Binary Document XOR Data Transformation Method 1

  • Artículo

Data transformed by Binary Document XOR Data Transformation Method 1 for encryption MUST be as specified in the EncryptData_Method1 procedure. This procedure takes the following parameters:

  • Password: An ASCII string that specifies the password to be used to encrypt the data.

  • Data: An array of unsigned 8-bit integers that specifies the data to be encrypted.

  • XorArrayIndex: An unsigned integer that specifies the initial index into the XOR obfuscation array to be used.

     FUNCTION EncryptData_Method1
     PARAMETERS Password, Data, XorArrayIndex
     DECLARE XorArray as array of 8-bit unsigned integers
  
     SET XorArray TO CreateXorArray_Method1(Password)
  
     FOR Index FROM 0 TO Data.Length
         SET Value TO Data[Index]
         SET Value TO (Value rotate left 5 bits)
         SET Value TO Value BITWISE XOR XorArray[XorArrayIndex]
         SET DATA[Index] TO Value
  
         INCREMENT XorArrayIndex
         SET XorArrayIndex TO XorArrayIndex MODULO 16
     END FOR
 END FUNCTION

Data transformed by the Binary Document XOR Data Transformation Method 1 for decryption MUST be as specified in the DecryptData_Method1 procedure. This procedure takes the following parameters:

  • Password: An ASCII string that specifies the password to be used to decrypt the data.

  • Data: An array of unsigned 8-bit integers that  specifies the data to be decrypted.

  • XorArrayIndex: An unsigned integer that specifies the initial index into the XOR obfuscation array to be used.

     FUNCTION DecryptData_Method1
     PARAMETERS Password, Data, XorArrayIndex
     DECLARE XorArray as array of 8-bit unsigned integers
  
     SET XorArray TO CreateXorArray_Method1(Password)
  
     FOR Index FROM 0 to Data.Length
         SET Value TO Data[Index]
         SET Value TO Value BITWISE XOR XorArray[XorArrayIndex]
         SET Value TO (Value rotate right 5 bits)
         SET Data[Index] TO Value
  
         INCREMENT XorArrayIndex
         SET XorArrayIndex TO XorArrayIndex MODULO 16
     END FOR
 END FUNCTION