Archethic's lib_dart #

Archethic dart library for Flutter

Usage #

This library aims to provide a easy way to create Archethic transaction and to send them over the network.

It supports the Archethic Cryptography rules which are:

Algorithm identification: keys are prepared by metadata bytes to indicate the curve used and the origin of the generation, and hashes are prepended by a byte to indicate the hash algorithm used. Those information help during the verification


    Ed25519   Software Origin   Public key
      |          |              |
      |  |-------|              |
      |  |   |------------------|        
      |  |   |     
    <<0, 0, 106, 58, 193, 73, 144, 121, 104, 101, 53, 140, 125, 240, 52, 222, 35, 181,
    13, 81, 241, 114, 227, 205, 51, 167, 139, 100, 176, 111, 68, 234, 206, 72>>

     NIST P-256  Software Origin   Public key
      |            |              |
      |  |---------|              |
      |  |  |----------------------
      |  |  |    
    <<1, 0, 4, 7, 161, 46, 148, 183, 43, 175, 150, 13, 39, 6, 158, 100, 2, 46, 167,
     101, 222, 82, 108, 56, 71, 28, 192, 188, 104, 154, 182, 87, 11, 218, 58, 107,
    222, 154, 48, 222, 193, 176, 88, 174, 1, 6, 154, 72, 28, 217, 222, 147, 106,
    73, 150, 128, 209, 93, 99, 115, 17, 39, 96, 47, 203, 104, 34>>

Key derivation:

To be able to retrieve previous public key, the Archethic network designs the key derivation through a seed (passphrase) and an index(number of previous public keys/transactions). The procedure is described as follows:

The seed generates a master key and an entropy used in the child keys generation.

                                                           / (256 bytes) Next private key
                      (256 bytes) Master key  --> HMAC-512
                    /                              Key: Master entropy,
  seed --> HMAC-512                                Data: Master key + index)
                    \
                     (256 bytes) Master entropy

API #

Cryptographic functions

deriveKeyPair(seed, index, curve)

It creates a new keypair into hexadecimal format

seed is hexadecimal encoding or Uint8Array representing the transaction chain seed to be able to derive and generate the keys
index is the number of transactions in the chain, to generate the actual and the next public key (see below the cryptography section)
curve is the elliptic curve to use for the key generation (can be "ed25519", "P256", "secp256k1") - default to: "ed25519"

import 'package:archethic_lib_dart/archethic_lib_dart.dart';

KeyPair keypair = crypto.deriveKeyPair('mysuperpassphraseorseed', 0);
// uint8ListToHex(keypair.publicKey) => 0100048cac473e46edd109c3ef59eec22b9ece9f99a2d0dce1c4ccb31ce0bacec4a9ad246744889fb7c98ea75c0f0ecd60002c07fae92f23382669ca9aff1339f44216

deriveAddress(seed, index, curve, hashAlgo)

It creates a transaction address by extract the public key from the key derivation and hash it into a hexadecimal format

seed is hexadecimal encoding or Uint8Array representing the transaction chain seed to be able to derive and generate the keys
index is the number of transactions in the chain, to generate the actual and the next public key (see below the cryptography section)
curve is the elliptic curve to use for the key generation (can be "ed25519", "P256", "secp256k1") - Default to "ed25519"
hashAlgo is the hash algorithm to create the address (can be "sha256", "sha512", "sha3-256", "sha3-512", "blake2b") - default to "sha256"

import 'package:archethic_lib_dart/archethic_lib_dart.dart';

String address = crypto.deriveAddress("mysuperpassphraseorseed", 0);
// Address: 00004195d45987f33e5dcb71edfa63438d5e6add655b216acfdd31945d58210fe5d2

ecEncrypt(data, publicKey)

Perform an ECIES encryption using a public key and a data

data Data to encrypt
publicKey Public key to derive a shared secret and for whom the content must be encrypted

import 'package:archethic_lib_dart/archethic_lib_dart.dart';

Uint8List cipher = crypto.ecEncrypt('dataToEncrypt' '00b1d3750edb9381c96b1a975a55b5b4e4fb37bfab104c10b0b6c9a00433ec4646');

aesEncrypt(data, publicKey)

Perform an AES encryption using a key and a data

data Data to encrypt
key Symmetric key

import 'package:archethic_lib_dart/archethic_lib_dart.dart';

Uint8List cipher = crypto.aesEncrypt('dataToEncrypt' '0000b1d3750edb9381c96b1a975a55b5b4e4fb37bfab104c10b0b6c9a00433ec4646');

Transaction building

new Transaction(type) creates a new instance of the transaction

type is the string defining the type of transaction to generate ("keychain", "keychain_access", "transfer", "hosting", "code_proposal", "code_approval", "token")

The transaction instance contains the following methods:

setCode(code)

Add the code in the data.code section of the transaction code is a string defining the smart contract

setContent(content)

Add the content in the data.content section of the transaction content is a string defining the smart contract

addOwnership(secret, authorizedKeys)

Add an ownership in the data.ownerships section of the transaction with a secret and its related authorized public keys to be able to decrypt it. This aims to prove the ownership or the delegatation of some secret to a given list of public keys. secret is the hexadecimal encoding or Uint8Array representing the encrypted secret authorizedKeys is a list of object represented by

publicKey is the hexadecimal encoding or Uint8Array representing the public key
encryptedSecretKey is the hexadecimal encoding or Uint8Array representing the secret key encrypted with the public key (see ecEncrypt)

addUCOTransfer(to, amount)

Add a UCO transfer to the data.ledger.uco.transfers section of the transaction

to is hexadecimal encoding or Uint8List representing the transaction address (recipient) to receive the funds
amount is the number of uco to send (int)

addTokenTransfer(to, amount, tokenAddress, tokenId)

Add a token transfer to the data.ledger.token.transfers section of the transaction

to is hexadecimal encoding or Uint8List representing the transaction address (recipient) to receive the funds
amount is the number of uco to send (int)
tokenAddress is hexadecimal encoding or Uint8List representing the token address to spend
tokenId is the ID of the token to use (default to 0)

addRecipient(to)

Add a recipient (for non UCO transfers, ie. smart contract interaction) to the data.recipient section of the transaction

to is hexadecimal encoding or Uint8List representing the transaction address (recipient)

build(seed, index, curve, hashAlgo)

Generate address, timestamp, previousPublicKey, previousSignature of the transaction and serialize it using a custom binary protocol.

seed is hexadecimal encoding or Uint8Array representing the transaction chain seed to be able to derive and generate the keys
index is the number of transactions in the chain, to generate the actual and the next public key (see below the cryptography section)
curve is the elliptic curve to use for the key generation (can be "ed25519", "P256", "secp256k1") - default to "P256"
hashAlgo is the hash algorithm to use to generate the address (can be "sha256", "sha512", "sha3-256", "sha3-512", "bake2b") - default to "sha256"

import 'package:archethic_lib_dart/archethic_lib_dart.dart';

Transaction tx = Transaction(type: 'transfer', data: Transaction.initData())
  .addUCOTransfer('0000b1d3750edb9381c96b1a975a55b5b4e4fb37bfab104c10b0b6c9a00433ec4646', toBigInt(0.420)) 
  .build('mysuperpassphraseorseed', 0, 'P256');

originSign(privateKey)

Sign the transaction with an origin device private key

privateKey is hexadecimal encoding or Uint8List representing the private key to generate the origin signature to able to perform the ProofOfWork and authorize the transaction

import 'package:archethic_lib_dart/archethic_lib_dart.dart';

final KeyPair originKeypair = crypto.deriveKeyPair('origin_seed', 0);
Transaction tx = Transaction(type: 'transfer', data: Transaction.initData())
  .addUCOTransfer('0000b1d3750edb9381c96b1a975a55b5b4e4fb37bfab104c10b0b6c9a00433ec4646', toBigInt((0.420)) 
  .build('mysuperpassphraseorseed', 0, 'P256') 
  .originSign(originKeypair.privateKey);

convertToJSON()

Export the transaction generated into JSON

import 'package:archethic_lib_dart/archethic_lib_dart.dart';

Transaction tx = Transaction(type: 'transfer', data: Transaction.initData())
 .addUCOTransfer('0000b1d3750edb9381c96b1a975a55b5b4e4fb37bfab104c10b0b6c9a00433ec4646', toBigInt(0.420)) 
 .build('mysuperpassphraseorseed', 0, 'P256') 
 .convertToJSON();

Remote Endpoint calls

getOriginKey()

Return the hardcoded origin private key for software, this is used for signing transaction (see OriginSign).

addOriginKey(originPublicKey, certificate, endpoint)

Query a node to add a new origin public to be authorized to sign transaction with the corresponding private key (see OriginSign).

originPublicKey is the public key to be added.
certificate is the certificate that prove the public key is allowed to be added.
endpoint is the HTTP URL to a Archethic node

Returns

{
  transaction_address: "..."
  status: "pending"
}

Getting the default origin Key :

final String originPrivateKey = await ApiService('https://testnet.archethic.net').getOriginKey();
final Transaction tx = Transaction(type: 'transfer', data: Transaction.initData());
...
tx.originSign(originPrivateKey);

Getting another origin key :

final String authPublicKey = '0001be992817b7db9807b1df5faa6bb23036e1f2189eeaab0e1f1260ede8642ecc76'
final String privateKey = '0001621d7c3bb971a245959679bf0879822a4df60c95c8f7f2193352d85498840b7d'
final String originPrivateKey = await ApiService('https://testnet.archethic.net').getOriginKey(authPublicKey, privateKey);
final Transaction tx = Transaction(type: 'transfer', data: Transaction.initData());
...
tx.originSign(originPrivateKey);

getTransactionIndex(addresses)

Query a node to find the length of the chain to retrieve the transaction index

addresses List of transaction addresses (in hexadecimal)

import 'package:archethic_lib_dart/archethic_lib_dart.dart';

Map<String, int> indexMap = await ApiService('https://testnet.archethic.net').getTransactionIndex(
       ['00b1d3750edb9381c96b1a975a55b5b4e4fb37bfab104c10b0b6c9a00433ec4646']);
int index = indexMap['00b1d3750edb9381c96b1a975a55b5b4e4fb37bfab104c10b0b6c9a00433ec4646'];
// 0

getLastTransaction(addresses)

Query a node to find the last transaction in the transaction chain from a list of addresses

addresses List of transaction addresses (in hexadecimal)

import 'package:archethic_lib_dart/archethic_lib_dart.dart';

Map<String, Transaction> transactionMap = await ApiService('https://testnet.archethic.net').getLastTransaction(
        ['00b1d3750edb9381c96b1a975a55b5b4e4fb37bfab104c10b0b6c9a00433ec4646']);
Transaction transaction = transactionMap['00b1d3750edb9381c96b1a975a55b5b4e4fb37bfab104c10b0b6c9a00433ec4646'];

getStorageNoncePublicKey()

Query a node to find the public key of the shared storage node key

import 'package:archethic_lib_dart/archethic_lib_dart.dart';

String storageNoncePublicKey =
       await ApiService('https://testnet.archethic.net').getStorageNoncePublicKey();
// 00b1d3750edb9381c96b1a975a55b5b4e4fb37bfab104c10b0b6c9a00433ec4646

getTransactionFee(tx)

Query a node to fetch the tx fee for a given transaction

tx Generated transaction

import 'package:archethic_lib_dart/archethic_lib_dart.dart';

Transaction tx = Transaction(...)
TransactionFee transactionFee = await ApiService('https://testnet.archethic.net').getTransactionFee(tx);

getTransactionOwnerships(addresses)

Query a node to find the ownerships (secrets and authorized keys) to given transactions addresses

addresses: List of transactions addresses

import 'package:archethic_lib_dart/archethic_lib_dart.dart';

String address = crypto.deriveAddress("mysuperpassphraseorseed", 0);
Map<String, List<Ownership>> ownershipsMap = await ApiService('https://testnet.archethic.net').getTransactionOwnerships([address]);
List<Ownership> ownerships = ownershipsMap[address];

Keychain / Wallet management

newKeychainTransaction(String seed, List

Creates a new transaction to build a keychain by embedding the on-chain encrypted wallet.

seed Keychain's seed
authorizedPublicKeys List of authorized public keys able to decrypt the wallet
originPrivateKey Key to make the origin signature of the transaction

newAccessKeychainTransaction(String seed, Uint8List keychainAddress, Uint8List originPrivateKey)

Creates a new keychain access transaction to allow a seed and its key to access a keychain

seed Keychain access's seed
keychainAddress Keychain's tx address
originPrivateKey Key to make the origin signature of the transaction

getKeychain(seed)

Retrieve a keychain from the keychain access transaction and decrypt the wallet to retrieve the services associated

seed Keychain access's seed

import 'package:archethic_lib_dart/archethic_lib_dart.dart';

Keychain keychain = await ApiService('https://testnet.archethic.net').getKeychain(accessKeychainSeed);

Once retrieved the keychain provide the following methods:

buildTransaction(tx, serviceName, index)

Generate address, previousPublicKey, previousSignature of the transaction and serialize it using a custom binary protocol, based on the derivation path, curve and hash algo of the service given in param.

tx is an instance of Transaction
serviceName is the service name to use for getting the derivation path, the curve and the hash algo
index is the number of transactions in the chain, to generate the actual and the next public key (see the cryptography section)

Return is the signed Transaction. Notice that the function also sign the Transaction given in param, so getting the return is not mandatory


final Transaction tx = Transaction(type: 'transfer', data: Transaction.initData()).addUCOTransfert(...);
final Keychain keychain = await ApiService('https://testnet.archethic.net').getKeychain(accessKeychainSeed);
final int index = (await ApiService('https://testnet.archethic.net').getTransactionIndex(keychain.deriveAddress('uco', 0))).chainLength);
Transaction signedTx = keychain.buildTransaction(tx, 'uco', index);

deriveAddress(service, index)

Derive an address for the given service at the index given

service: Service name to identify the derivation path to use
index: Chain index to derive (default to 0)

Keychain keychain = await ApiService('https://testnet.archethic.net').getKeychain(accessKeychainSeed);
Uint8List genesisUCOAddress = keychain.deriveAddress('uco', index: 0);

deriveKeypair(service, index)

Derive a keypair for the given service at the index given

service: Service name to identify the derivation path to use
index: Chain index to derive (default to 0)

Keychain keychain = await ApiService('https://testnet.archethic.net').getKeychain(accessKeychainSeed);
KeyPair keyPair = keychain.deriveKeypair('uco', index: 0);

toDID()

Return a Decentralized Identity document from the keychain. (This is used in the transaction's content of the keychain tx)

Keychain keychain = await ApiService('https://testnet.archethic.net').getKeychain(accessKeychainSeed);
final Map<String, dynamic> did = keychain.toDID();
log(did)
{
  "@context": [
     "https://www.w3.org/ns/did/v1"
  ],
  "id": "did:archethic:keychain_address",
  "authentification": servicesMaterials, //list of public keys of the services
  "verificationMethod": servicesMaterials //list of public keys of the services
}

addService(String name, String derivationPath, {String curve = 'ed25519', String hashAlgo = 'sha256'})

Add a service into the keychain

name: Name of the service to add
derivationPath: Crypto derivation path
curve: Elliptic curve to use
hashAlgo: Hash algo

Keychain keychain = await ApiService('https://testnet.archethic.net').getKeychain(accessKeychainSeed);
keychain.addService("nft1", "m/650'/1/0");
log(keychain)
{
  version: 1,
  seed: "mymasterseed",
  services: {
    uco: {
      derivationPath: "m/650'/0/0",
      curve: "ed25519",
      hashAlgo: "sha256"
    },
    nft1: {
      derivationPath: "m/650'/1/0",
      curve: "ed25519",
      hashAlgo: "sha256"
    }
  }
}

Running the tests #

dart test --exclude-tags noCI

archethic_lib_dart 1.0.27 archethic_lib_dart: ^1.0.27 copied to clipboard

Metadata