Chacha20 class abstract

ChaCha20 (RFC 7539) StreamingCipher.

We recommend you to use Chacha20.poly1305Aead(), which does message authentication with a standard AEAD construction for ChaCha20.

About the algorithm

• secretKeyLength is 32 bytes.
• nonceLength is 12 bytes.\

Example

import 'package:better_cryptography/better_cryptography.dart';

Future<void> main() async {
  final message = <int>[1,2,3];

  final algorithm = Chacha20(macAlgorithm: Hmac.sha256());
  final secretKey = await algorithm.newSecretKey();

  // Encrypt
  final secretBox = await algorithm.encrypt(
    message,
    secretKey: secretKey,
  );
  print('Nonce: ${secretBox.nonce}')
  print('Ciphertext: ${secretBox.cipherText}')
  print('MAC: ${secretBox.mac.bytes}')

  // Decrypt
  final clearText = await algorithm.decrypt(
    secretBox,
    secretKey: secretKey,
  );
  print('Cleartext: $clearText');
}

In need of synchronous APIs?

If you need to perform operations synchronously, use DartChacha20 in package:better_cryptography/dart.dart.

Inheritance

• Object
• Cipher
• StreamingCipher
• Chacha20

Implementers

• DartChacha20

Constructors

Chacha20.new({required MacAlgorithm macAlgorithm})

factory

Chacha20.constructor()

Constructor for classes that extend this class.

const

Chacha20.poly1305Aead()

AEAD_CHACHA20_POLY1305 (https://tools.ietf.org/html/rfc7539(RFC 7539)) Cipher.

factory

Properties

hashCode → int

The hash code for this object.

no setter, override

macAlgorithm → MacAlgorithm

Message authentication code (MacAlgorithm) used by the cipher.

no setter, inherited

nonceLength → int

Number of bytes in the nonce ("Initialization Vector", "IV", "salt").

no setter, override

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

secretKeyLength → int

Number of bytes in the SecretKey.

no setter, override

Methods

decrypt(SecretBox secretBox, {required SecretKey secretKey, List<int> aad = const <int>[], int keyStreamIndex = 0}) → Future<List<int>>

Decrypts a ciphertext.

inherited

encrypt(List<int> clearText, {required SecretKey secretKey, List<int>? nonce, List<int> aad = const <int>[], int keyStreamIndex = 0}) → Future<SecretBox>

Encrypts a cleartext.

inherited

newNonce() → List<int>

Generates a new nonce with the correct length (nonceLength).

inherited

newSecretKey() → Future<SecretKey>

Generates a new SecretKey with the correct length (secretKeyLength).

inherited

newSecretKeyFromBytes(List<int> bytes) → Future<SecretKey>

Constructs a new SecretKey from the bytes.

inherited

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

toString() → String

A string representation of this object.

override

Operators

operator ==(Object other) → bool

The equality operator.

override