Encrypts or decrypts data represented as a hexadecimal string using a specified mode. The key and initialization vector are represented as a hexadecimal string.
Public Declare Function DES_HexMode Lib "diCryptoSys.dll"
(ByVal strOutput As String, ByVal strInput As String,
ByVal strHexKey As String, ByVal bEncrypt As Boolean,
ByVal strMode As String, ByVal strHexIV As String) As Long
nRet = DES_HexMode(strOutput, strInput, strHexKey, bEncrypt, strMode, strHexIV)
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.String specifying the confidentiality mode:String containing the initialization vector (IV)
in hexadecimal.
long _stdcall DES_HexMode(char *lpszOutput, const char *lpszInput, const char *lpszKey,
int bEncrypt, const char *lpszMode, const char *lpszIV);
Long: If successful, the return value is 0;
otherwise it returns a non-zero error code.
Des.Encrypt Method (String, String, Mode, String)
Des.Decrypt Method (String, String, Mode, String)
des.HexMode
Public Function HexMode(ByVal strInput As String, ByVal strHexKey As String, ByVal bEncrypt As Boolean, ByVal strMode As String, ByVal strHexIV As String) As String
See des.HexMode.
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.
Both the key string strHexKey and the initialization vector strHexIV
must be exactly 16 hex characters long
(i.e. representing exactly 8 bytes), unless strMode is ECB,
in which case strIV is ignored (use "").
Valid hexadecimal characters are [0-9A-Fa-f].
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.
Dim nRet As Long
Dim strOutput As String
Dim strInput As String
Dim strKey As String
Dim strIV As String
Dim sCorrect As String
' "Now is the time for all " in hex
strInput = "4e6f77206973207468652074696d6520666f7220616c6c20"
strKey = "0123456789abcdef"
strIV = "1234567890abcdef"
sCorrect = "e5c7cdde872bf27c43e934008c389c0f683788499a7c05f6"
' Set strOutput to be same length as strInput
strOutput = String(Len(strInput), " ")
Debug.Print "KY="; strKey
Debug.Print "IV="; strIV
Debug.Print "PT="; strInput
' Encrypt in one-off process
nRet = DES_HexMode(strOutput, strInput, strKey, True, "CBC", strIV)
Debug.Print "CT="; strOutput
Debug.Print "OK="; sCorrect
' Now decrypt back to plain text
strInput = strOutput
nRet = DES_HexMode(strOutput, strInput, strKey, DECRYPT, "CBC", strIV)
Debug.Print "P'="; strOutput
This should result in output as follows:
KY=0123456789abcdef IV=1234567890abcdef PT=4e6f77206973207468652074696d6520666f7220616c6c20 CT=E5C7CDDE872BF27C43E934008C389C0F683788499A7C05F6 OK=e5c7cdde872bf27c43e934008c389c0f683788499a7c05f6 P'=4E6F77206973207468652074696D6520666F7220616C6C20