ARC4 Encryption (ARCFOUR)

Demonstrates simple ARC4 encryption to match some simple test vectors published by Wikipedia. ARC4 is a fast stream cipher supporting key lengths from 8 to 2048 bits (i.e. from 1 to 256 bytes). It is not a block cipher, so there is no padding, no modes, and no initialization vector.

 Chilkat Perl Module Downloads for Windows, Linux, and MAC OS X

use chilkat();

$crypt = new chilkat::CkCrypt2();

$success = $crypt->UnlockComponent("Anything for 30-day trial");
if ($success != 1) {
    print "Crypt component unlock failed" . "\n";
    exit;
}

#  Set the encryption algorithm to ARC4:
$crypt->put_CryptAlgorithm("arc4");

#  We want the encrypted output to be a hex-encoded string.
$crypt->put_EncodingMode("hex");

#  Encrypt some test vectors from Wikipedia:

#  The key length (in bits) is equal to the number of us-ascii
#  bytes in our key string * 8.

# ARC4( "Key", "Plaintext" ) == BBF316E8D940AF0AD3
$crypt->put_KeyLength(24);
$crypt->SetEncodedKey("Key","ascii");
$cipherText = $crypt->encryptStringENC("Plaintext");
print $cipherText . "\r\n";
$plainText = $crypt->decryptStringENC($cipherText);
print $plainText . "\r\n";

# ARC4( "Wiki", "pedia" ) == 1021BF0420
$crypt->put_KeyLength(32);
$crypt->SetEncodedKey("Wiki","ascii");
$cipherText = $crypt->encryptStringENC("pedia");
print $cipherText . "\r\n";
$plainText = $crypt->decryptStringENC($cipherText);
print $plainText . "\r\n";

# ARC4( "Secret", "Attack at dawn" ) == 45A01F645FC35B383552544B9BF5
$crypt->put_KeyLength(48);
$crypt->SetEncodedKey("Secret","ascii");
$cipherText = $crypt->encryptStringENC("Attack at dawn");
print $cipherText . "\r\n";
$plainText = $crypt->decryptStringENC($cipherText);
print $plainText . "\r\n";

#  Note: The call to SetEncodedKey serves to set the key
#  to the us-ascii bytes of the string.