Lua

Blowfish OFB Output Feedback Mode Encryption

See more Encryption Examples

Demonstrates how to encrypt using Blowfish OFB (Output Feedback) mode. Lua

local chilkat = require("chilkat")

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

local crypt = chilkat.Crypt2.new()

-- Use "blowfish2" to produce correct results that match published blowfish test vectors.
crypt.crypt_algorithm = "blowfish2"
-- Set the cipher mode to Output Feedback
crypt.cipher_mode = "ofb"
crypt.key_length = 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.
crypt.encoding_mode = "hex"

-- The block size of the blowfish algoirthm is 8 bytes, therefore the IV is 8 bytes.
local ivHex = "0001020304050607"
crypt:set_encoded_iv(ivHex, "hex")

-- The secret key must equal the size of the key.  For
-- 256-bit encryption, the binary secret key is 32 bytes.
local keyHex = "603deb1015ca71be2b73aef0857d77811f352c073b6108d72d9810a30914dff4"
crypt:set_encoded_key(keyHex, "hex")

-- Encrypt a string...
local encStr = crypt:encrypt_string_enc("Emergencies have always been the pretext on which the safeguards of individual liberty have been eroded. -- Friedrich Hayek")
print(encStr)

local decrypt = chilkat.Crypt2.new()
decrypt.crypt_algorithm = "blowfish2"
decrypt.cipher_mode = "ofb"
decrypt.key_length = 256
decrypt.encoding_mode = "hex"
decrypt:set_encoded_iv(ivHex, "hex")
decrypt:set_encoded_key(keyHex, "hex")

-- Now decrypt:
local decStr = decrypt:decrypt_string_enc(encStr)
print(decStr)