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uniris_lib_dart

Uniris dart library for Flutter based on Official Uniris Javascript library for Node and Browser

Usage

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

It supports the Uniris Cryptography rules which are:

  • Algorithm identification: the first byte of key and hashes identify the curve or the digest algorithm used to help determine which algorithm during verification.

    
        Ed25519    Public key
          |           /
          |          /
        <<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   Public key
          |          /
          |         /
        <<1, 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 Uniris 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 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 (optional, "ed25519" by default) is the elliptic curve to use for the key generation (can be "ed25519", "P256", "secp256k1")
  import 'package:uniris_lib_dart/crypto.dart' as crypto;
  import 'package:uniris_lib_dart/key_pair.dart';
  import 'package:uniris_lib_dart/utils.dart';

  KeyPair keypair = crypto.deriveKeyPair("mysuperpassphraseorseed", 0);
  // uint8ListToHex(keypair.publicKey) => 00a6e144cdd34c608f88cc5a92d0962e7cfe9843b0bb62fefbdb60eb41814b7c92

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:uniris_lib_dart/crypto.dart' as crypto;
  import 'package:uniris_lib_dart/key_pair.dart';
  import 'package:uniris_lib_dart/utils.dart';

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

aesEncrypt(data, publicKey)

Don't available for the moment... soon...

TransactionBuilding

new TransactionBuilder(type) creates a new instance of the transaction builder

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

The transaction builder 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

setSecret(secret)

Add the secret in the data.keys.secret section of the transaction secret is the hexadecimal encoding or Uint8List representing the encrypted secret

addAuthorizedKey(publicKey, encryptedSecretKey)

Add an authorized public key to decrypt the secret to the data.keys.authorizedKeys section of the transaction

  • publicKey is the hexadecimal encoding or Uint8List representing the public key
  • encryptedSecretKey is the hexadecimal encoding or Uint8List 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 (double)

addNFTTransfer(to, amount, nft_address)

Add a NFT transfer to the data.ledger.nft.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 (double)
  • nft_address is hexadecimal encoding or Uint8List representing the NFT address to spend

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, originSignature of the transaction and serialize it using a custom binary protocol.

  • seed is hexadecimal encoding or Uint8List 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")
  • hashAlgo is the hash algorithm to use to generate the address (can be "sha256", "sha512", "sha3-256", "sha3-512", "blake2b")
  import 'package:uniris_lib_dart/transaction_builder.dart';

  var tx = new TransactionBuilder("transfer")
    .addUCOTransfer("00b1d3750edb9381c96b1a975a55b5b4e4fb37bfab104c10b0b6c9a00433ec4646", 0.420) 
    .build("mysuperpassphraseorseed", 0) 

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:uniris_lib_dart/transaction_builder.dart';

  var tx = new TransactionBuilder("transfer")
    .addUCOTransfer("00b1d3750edb9381c96b1a975a55b5b4e4fb37bfab104c10b0b6c9a00433ec4646", 0.420) 
    .build("mysuperpassphraseorseed", 0) 
    .originSign(originPrivateKey)

toJSON()

Export the transaction generated into JSON

  import 'package:uniris_lib_dart/transaction_builder.dart';

  var tx = new TransactionBuilder("transfer")
    .addUCOTransfer("00b1d3750edb9381c96b1a975a55b5b4e4fb37bfab104c10b0b6c9a00433ec4646", 0.420) 
    .build("mysuperpassphraseorseed", 0) 
    .toJSON()

Remote Endpoint calls

sendTransaction(tx, endpoint)

Dispatch the transaction to a node by serializing a GraphQL request

Don't available for the moment... soon...

getTransactionIndex(address, endpoint)

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

Don't available for the moment... soon...

getStorageNoncePublicKey(endpoint)

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

Don't available for the moment... soon...

Running the tests

flutter test

Libraries

uniris_lib