TDEA_Hex encrypts or decrypts data
represented as a hexadecimal string
using a key represented in hexadecimal notation.
The process is carried out in one step in Electronic Codebook (EBC) mode.
Public Declare Function TDEA_Hex Lib "diCryptoSys.dll"
(ByVal strOutput As String, ByVal strInput As String, ByVal strKey As String,
ByVal bEncrypt As Boolean) As Long
nRet = TDEA_Hex(strOutput, strInput, strKey, bEncrypt)
String of sufficient length to receive the output.String containing the input data in hexadecimal.String containing the key in hexadecimal.Boolean direction flag:
set as True to encrypt or False
to decrypt.
long _stdcall TDEA_Hex(char *lpszOutput, const char *lpszInput,
const char *lpszKey, int bEncrypt);
Long: If successful, the return value is 0;
otherwise it returns a non-zero error code.
The length of the input string strInput must be a multiple of 16 hex characters long (i.e. representing a multiple of 8 bytes). If not, an error code will be returned. The key string strKey must be exactly 48 hex characters long (i.e. representing exactly 24 bytes). The parity bit is ignored. The output string strOutput must be set up with at least the same number of characters as the input string before calling. The variables strOutput and strInput should be different. Valid hexadecimal characters are [0-9A-Fa-f].
Dim nRet As Long
Dim strOutput As String
Dim strInput As String
Dim strKey As String
Dim bEncrypt As Boolean
Dim sCorrect As String
strInput = "8000000000000000"
strKey = "010101010101010101010101010101010101010101010101"
sCorrect = "95F8A5E5DD31D900"
' Set strOutput to be same length as strInput
strOutput = String(Len(strInput), " ")
Debug.Print "KY="; strKey
Debug.Print "PT="; strInput
' Encrypt
nRet = TDEA_Hex(strOutput, strInput, strKey, ENCRYPT)
Debug.Print "CT="; strOutput, "Return value="; nRet
Debug.Print "OK="; sCorrect
' Decrypt back
strInput = strOutput
nRet = TDEA_Hex(strOutput, strInput, strKey, DECRYPT)
Debug.Print "P'="; strOutput, "Return value="; nRet
This should result in output as follows:
KY=010101010101010101010101010101010101010101010101 PT=8000000000000000 CT=95F8A5E5DD31D900 Return value= 0 OK=95F8A5E5DD31D900 P'=8000000000000000 Return value= 0