Visual FoxPro

Twofish OFB Output Feedback Mode Encryption

See more Encryption Examples

Demonstrates how to encrypt using Twofish OFB (Output Feedback) mode. Visual FoxPro

LOCAL loCrypt
LOCAL lcIvHex
LOCAL lcKeyHex
LOCAL lcEncStr
LOCAL loDecrypt
LOCAL lcDecStr

* This example assumes the Chilkat API to have been previously unlocked.
* See Global Unlock Sample for sample code.

loCrypt = CreateObject('Chilkat.Crypt2')

loCrypt.CryptAlgorithm = "twofish"
* Set the cipher mode to Output Feedback
loCrypt.CipherMode = "ofb"
loCrypt.KeyLength = 256

* EncodingMode specifies the encoding of the output for
* encryption, and the input for decryption.
* It may be "hex", "url", "base64", "quoted-printable", or many other choices.
loCrypt.EncodingMode = "hex"

lcIvHex = "000102030405060708090A0B0C0D0E0F"
loCrypt.SetEncodedIV(lcIvHex,"hex")

* The secret key must equal the size of the key.  For
* 256-bit encryption, the binary secret key is 32 bytes.
lcKeyHex = "603deb1015ca71be2b73aef0857d77811f352c073b6108d72d9810a30914dff4"
loCrypt.SetEncodedKey(lcKeyHex,"hex")

* Encrypt a string...
lcEncStr = loCrypt.EncryptStringENC("Without music to decorate it, time is just a bunch of boring production deadlines or dates by which bills must be paid. -- Frank Zappa")
? lcEncStr

loDecrypt = CreateObject('Chilkat.Crypt2')
loDecrypt.CryptAlgorithm = "twofish"
loDecrypt.CipherMode = "ofb"
loDecrypt.KeyLength = 256
loDecrypt.EncodingMode = "hex"
loDecrypt.SetEncodedIV(lcIvHex,"hex")
loDecrypt.SetEncodedKey(lcKeyHex,"hex")

* Now decrypt:
lcDecStr = loDecrypt.DecryptStringENC(lcEncStr)
? lcDecStr

RELEASE loCrypt
RELEASE loDecrypt