[글쓴이:] 다솜돌이

Ethereum의 경우 버전에 따라 트랜잭션에 gasPrice를 쓸 지, maxFeePerGas/maxPriorityFeePerGas 를 쓸 지가 정해진다. https://ethereum.stackexchange.com/questions/147692/how-to-get-public-key-by-the-transaction-hash 를 참고.

주소를 얻을 때, Public key에서 앞의 한 바이트(0x04)를 빼고, keccak256을 돌리는 부분에 유의하자.

const { ethers } = require("hardhat");

// 트랜잭션 서명 값
// const r = "0xe680637b83a1dd102364503bd77979b87c92ba651132a4df8e839af69c20af95";
// const s = "0x65becfa32384747adb05f543397baaf23d1c55fa28d0c9a38924912dae6df28f";
// const v = 12266684226873;
// const chainId = 6133342113419;

// 트랜잭션 해시
const txHash = "0xc7159866fb5b94d291e8624bdc731b7a6d46533b398065de7aa7dd1af7b6aa36";
const ethermainHash = "0xef120deb6ff2e516ad44724d220c0cd73166d169a2a0b0f66dfb5613d2d6169c"
const sepoliaHash = "0xfe4ddad4cae9ea353fc91441ee5db6c70bd5468673d907926be92dd4b8a63f63"

// 실제 트랜잭션에 사용된 private key. 아무거나 넣자.
const privateKey = "0x0000000000000000000000000000000000000000000000000000000000000001";

// Web3 프로바이더 설정 (Hardhat 로컬 노드 사용 예시)
const provider = ethers.provider;

// 서명된 트랜잭션 정보 가져오기
async function getPublicKeyFromTransactionHash(provider, txHash) {
  // Fetch the transaction using the transaction hash and provier
  const tx = await provider.getTransaction(txHash);

  console.log(tx);

  // Extract the all the relevant fields from the transaction (We need all of them)
  const unsignedTx = {
    gasPrice: tx.gasPrice,
    gasLimit: tx.gasLimit,
    value: tx.value,
    nonce: tx.nonce,
    data: tx.data,
    chainId: tx.chainId,
    to: tx.to,
    type: tx.type,
    // maxFeePerGas: tx.maxFeePerGas,
    // maxPriorityFeePerGas: tx.maxPriorityFeePerGas,
  };

  // Serializing tx without the signature
  const serializedTx = ethers.utils.serializeTransaction(unsignedTx);

  // Extract the signature (v, r, s) from the transaction
  const { v, r, s } = tx;

  // Join splitted signature
  const signature = ethers.utils.joinSignature({ v, r, s });

  const recoveredPublicKey = ethers.utils.recoverPublicKey(
    ethers.utils.keccak256(serializedTx),
    signature,
  );
  console.log("recoveredPublicKey:", recoveredPublicKey);
  const keccak = ethers.utils.keccak256("0x" + recoveredPublicKey.slice(4))
  console.log("keccak256 of recoveredPublicKey:", keccak, ethers.utils.keccak256("0x" + recoveredPublicKey.slice(4)));

  // Recover the address or public key with (replace recoverAddress by recoverPublicKey) associated with the transaction
  return ethers.utils.recoverAddress(
    ethers.utils.keccak256(serializedTx),
    signature
  );
}

async function main() {
  const address = await getPublicKeyFromTransactionHash(provider, txHash);

  console.log("Address:", address);
}

main()
.then(() => process.exit(0))
.catch((error) => {
    console.error(error);
    process.exit(1);
});