Dart

ARC4 Encryption (ARCFOUR)

See more Encryption Examples

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

import 'package:chilkat/chilkat.dart';

void main() {
  // This example assumes the Chilkat API to have been previously unlocked.
  // See Global Unlock Sample for sample code.

  final crypt = CkCrypt2();

  // Set the encryption algorithm = "arc4"	
  crypt.cryptAlgorithm = '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:
  crypt.keyLength = 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".
  crypt.encodingMode = '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.
  final keyHex = '000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F';
  crypt.setEncodedKey(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).
  final encStr = crypt.encryptStringENC('The quick brown fox jumps over the lazy dog.');
  print(encStr);

  // Now decrypt:
  final decStr = crypt.decryptStringENC(encStr);
  print(decStr);
}