PureBasic

ARC4 Encryption (ARCFOUR)

See more Encryption Examples

ARC4 (ARCFOUR) encryption. The Chilkat encryption component supports the ARC4 streaming encryption algorithm. PureBasic

IncludeFile "CkCrypt2.pb"

Procedure ChilkatExample()

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

    crypt.i = CkCrypt2::ckCreate()
    If crypt.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ; Set the encryption algorithm = "arc4"	
    CkCrypt2::setCkCryptAlgorithm(crypt, "arc4")

    ; KeyLength may range from 1 byte to 256 bytes.
    ; (i.e. 8 bits to 2048 bits)
    ; ARC4 key sizes are typically in the range of 
    ; 40 to 128 bits.
    ; The KeyLength property is specified in bits:
    CkCrypt2::setCkKeyLength(crypt, 128)

    ; Note: The PaddingScheme and CipherMode properties
    ; do not apply w/ ARC4.  ARC4 does not encrypt in blocks --
    ; it is a streaming encryption algorithm. The number of output bytes
    ; is exactly equal to the number of input bytes.

    ; EncodingMode specifies the encoding of the output for
    ; encryption, and the input for decryption.
    ; It may be "hex", "url", "base64", or "quoted-printable".
    CkCrypt2::setCkEncodingMode(crypt, "hex")

    ; Note: ARC4 does not utilize initialization vectors.  IV's only
    ; apply to block encryption algorithms.  

    ; The secret key must equal the size of the key.
    ; For 128-bit encryption, the binary secret key is 16 bytes.
    keyHex.s = "000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F"
    CkCrypt2::ckSetEncodedKey(crypt,keyHex,"hex")

    ; Encrypt a string...
    ; The output length is exactly equal to the input.  In this
    ; example, the input string is 44 chars (ANSI bytes) so the
    ; output is 44 bytes -- and when hex encoded results in an
    ; 88-char string (2 chars per byte for the hex encoding).
    encStr.s = CkCrypt2::ckEncryptStringENC(crypt,"The quick brown fox jumps over the lazy dog.")
    Debug encStr

    ; Now decrypt:
    decStr.s = CkCrypt2::ckDecryptStringENC(crypt,encStr)
    Debug decStr


    CkCrypt2::ckDispose(crypt)


    ProcedureReturn
EndProcedure