112-bit 3DES Encryption

Demonstrates how to do 112-bit 3DES encryption.

Download: Chilkat .NET Assemblies

Dim crypt As New Chilkat.Crypt2()

Dim success As Boolean
success = crypt.UnlockComponent("Anything for 30-day trial")
If (success <> true) Then
    MsgBox("Crypt component unlock failed")
    Exit Sub
End If


'  Specify 3DES for the encryption algorithm:
crypt.CryptAlgorithm = "3des"

'  CipherMode may be "ecb" or "cbc"
crypt.CipherMode = "ecb"

'  Set the key length
crypt.KeyLength = 112

'  Choose a padding scheme...
crypt.PaddingScheme = 0

'  EncodingMode specifies the encoding of the output for
'  encryption, and the input for decryption.
'  It may be "hex", "url", "base64", or "quoted-printable".
crypt.EncodingMode = "hex"

'  An initialization vector is required if using CBC or CFB modes.
'  ECB mode does not use an IV.
'  The length of the IV is equal to the algorithm's block size.
'  It is NOT equal to the length of the key.
Dim ivHex As String
ivHex = "0001020304050607"
crypt.SetEncodedIV(ivHex,"hex")

'  The secret key must equal the size of the key.
'  Remember, DES (i.e. 3DES) uses a parity bit in the key,
'  so 112-bit 3DES requires 128 bits of key material
'  (i.e. 16 bytes)
Dim keyHex As String
keyHex = "11165395389c904862912aba16d315b8"
crypt.SetEncodedKey(keyHex,"hex")

'  Encrypt a string...
Dim encStr As String
encStr = crypt.EncryptStringENC("999999987")
'  The result should be: 8CDBB138C11EDC3A77F04E488B46385C
MsgBox(encStr)

'  Now decrypt:
Dim decStr As String
decStr = crypt.DecryptStringENC(encStr)
MsgBox(decStr)