Raw Signing

Overview

Raw signing allows you to sign arbitrary data with your MPC wallet, giving you full control over the message format and hashing process. This is useful for custom signing scenarios, non-standard message formats, or when you need to implement chain-specific signing requirements. Note that raw signing is currently only available for EVM chains.

Basic Raw Signing

React

  import { keccak256, stringToHex } from 'viem';
  import { DynamicWaasEVMConnector } from '@dynamic-labs/sdk-react-core';

  const rawMessage = "Hello World";

  const connector = primaryWallet.connector as DynamicWaasEVMConnector;
  const hash = keccak256(stringToHex(rawMessage)).slice(2);

  const signature = await connector.signRawMessage({
      accountAddress: primaryWallet.address,
      message: hash,
  });
  console.log("Signature:", signature);

React Native

  import { useDynamicClient } from './path-to-your-client';

  const client = useDynamicClient();
  const { signedMessage } = await client.wallets.signMessage({
    wallet,
    message,
  });

Flutter

You need to have our dynamic_sdk_web3_dart package installed for this.

  String hash = bytesToHex(keccak256(utf8.encode("Hello World")), include0x: false);
  final response = await DynamicSDK.instance.wallets.signMessage(
  message: _controller.text,
  wallet: widget.wallet,
  );

Swift

  // Use the plain string directly when UTF-8 encoding is expected
  let message = "Hello World"

Encoding Options

Dynamic supports different encoding formats for your raw messages:

Hexadecimal Encoding

Most common for blockchain applications. The message is encoded as a hex string.

React

  import { stringToHex } from 'viem';

  const message = "Hello World";
  const hexEncoded = stringToHex(message);
  // Result: "0x48656c6c6f20576f726c64"

React Native

  import { stringToHex } from 'viem';

  const message = "Hello World";
  const hexEncoded = stringToHex(message);
  // Result: "0x48656c6c6f20576f726c64"

Flutter

You need to have our dynamic_sdk_web3_dart installed

  String hash = bytesToHex(keccak256(utf8.encode("Hello World")), include0x: false);

Swift

  import Foundation

  let message = "Hello World"
  let data = Data(message.utf8)
  let hexEncoded = "0x" + data.map { String(format: "%02x", $0) }.joined()
  // Result: 0x48656c6c6f20576f726c64

UTF-8 Text Encoding

For plain text messages that don’t require hex encoding.

React

  const message = "Hello World";
  // Use directly as string

React Native

  const message = "Hello World";
  // Use directly as string

Flutter

  final message = "Hello World";
  // Use directly as string

Swift

  // Use the plain string directly when UTF-8 encoding is expected
  let message = "Hello World"

Hash Functions

Different hash functions serve different purposes in cryptographic signing:

Keccak256 (Ethereum Standard)

Most commonly used for Ethereum and EVM-compatible chains:

React

  import { keccak256, stringToHex } from 'viem';

  const message = "Hello World";
  const hash = keccak256(stringToHex(message));

React Native

  import { keccak256, stringToHex } from 'viem';

  const message = "Hello World";
  const hash = keccak256(stringToHex(message));

Flutter

You need to have our dynamic_sdk_web3_dart installed

  String hash = keccak256(utf8.encode("Hello World"));

Swift

  import Foundation
  import CryptoSwift // provides keccak-256

  let message = "Hello World"
  let hash = message.bytes.sha3(.keccak256).toHexString()

SHA256

Standard cryptographic hash function:

React

  import { createHash } from 'crypto';

  const message = "Hello World";
  const hash = createHash('sha256').update(message).digest('hex');

React Native

  import { createHash } from 'crypto';

  const message = "Hello World";
  const hash = createHash('sha256').update(message).digest('hex');

Flutter

You’d need to also add the crypto package into pubspec.yaml.

  String input = "Hello, world!";
  
  // Convert the input string to a list of bytes
  var bytes = utf8.encode(input); 

  // Perform the SHA256 hash
  var digest = sha256.convert(bytes);

  // Print the digest as a hex string
  print("Digest as hex string: $digest"); 
  
  // Example output: Digest as hex string: 315f5bdb784dce8416861858983995ee1060960a00b21a8918817a468d66141a

Swift

  import Foundation
  import CryptoKit

  let messageData = Data("Hello World".utf8)
  let digest = SHA256.hash(data: messageData)
  let hex = digest.map { String(format: "%02x", $0) }.joined()

Advanced Examples

Custom Message Formatting

For chains with specific message formatting requirements:

React

  // Example: Custom prefix for a specific blockchain
  const customPrefix = "\x19MyChain Signed Message:\n";
  const message = "Hello World";
  const formattedMessage = customPrefix + message.length + message;

  const hash = keccak256(stringToHex(formattedMessage)).slice(2);
  const signature = await connector.signRawMessage({
      accountAddress: primaryWallet.address,
      message: hash,
  });

React Native

  import { useDynamicClient } from './path-to-your-client';

  const client = useDynamicClient();
        
  // Example: Custom prefix for a specific blockchain
  const customPrefix = "\x19MyChain Signed Message:\n";
  const message = "Hello World";
  const formattedMessage = customPrefix + message.length + message;

  const hash = keccak256(stringToHex(formattedMessage)).slice(2);
  const { signedMessage } = await client.wallets.signMessage({
    wallet,
    hash,
  });

Flutter

You need to have our dynamic_sdk_web3_dart installed

  import 'dart:convert';
  import 'package:web3dart/crypto.dart';

  String customPrefix = "\x19MyChain Signed Message:\n";
  String message = "Hello World";
  String formattedMessage = customPrefix + message.length.toString() + message;
  String hash = bytesToHex(keccak256(utf8.encode(formattedMessage)), include0x: false);

  final response = await DynamicSDK.instance.wallets.signMessage(
    message: hash,
    wallet: widget.wallet,
  );

Swift

  import Foundation
  import CryptoSwift // for keccak-256 hashing

  let customPrefix = "\u{0019}MyChain Signed Message:\n"
  let message = "Hello World"
  let formattedMessage = customPrefix + "\(message.count)" + message

  // Hash the formatted message (no 0x prefix)
  let hash = formattedMessage.bytes.sha3(.keccak256).toHexString()

  // Pass `hash` into your signing call, e.g. wallets.signMessage(...)

Binary Data Signing

For signing binary data or structured payloads:

React

// Example: Signing a binary payload
const binaryData = new Uint8Array([0x01, 0x02, 0x03, 0x04]);
const hexData = Array.from(binaryData)
    .map(b => b.toString(16).padStart(2, '0'))
    .join('');

const signature = await connector.signRawMessage({
    accountAddress: primaryWallet.address,
    message: hexData,
});

React Native

import { useDynamicClient } from './path-to-your-client';

const client = useDynamicClient();

const binaryData = new Uint8Array([0x01, 0x02, 0x03, 0x04]);
const hexData = Array.from(binaryData)
  .map(b => b.toString(16).padStart(2, '0'))
  .join('');

const { signedMessage } = await client.wallets.signMessage({
  wallet,
  hash: hexData, // raw hex payload without 0x
});

Swift

  import Foundation

  let binaryData: [UInt8] = [0x01, 0x02, 0x03, 0x04]
  let hexData = binaryData.map { String(format: "%02x", $0) }.joined()

  // Pass `hexData` into your signing call, e.g. wallets.signMessage(...)

Flutter

  import 'package:web3dart/crypto.dart';

  final data = <int>[0x01, 0x02, 0x03, 0x04];
  final hexData = bytesToHex(data, include0x: false);

  final response = await DynamicSDK.instance.wallets.signMessage(
    message: hexData,
    wallet: widget.wallet,
  );