chaingate/dist/utils/evmTx.js

Multi-chain cryptocurrency SDK for TypeScript — unified API for Bitcoin, Ethereum, Litecoin, Dogecoin, Bitcoin Cash, Polygon, Arbitrum, and any EVM-compatible chain. Create wallets, query balances, send transactions, and manage tokens and NFTs across UTXO

"use strict";
/**
 * EIP-1559 (type-2) transaction serialization and signing.
 *
 * Produces the signed raw transaction hex ready for broadcast.
 */
Object.defineProperty(exports, "__esModule", { value: true });
exports.signEip1559Transaction = signEip1559Transaction;
exports.signLegacyTransaction = signLegacyTransaction;
const secp256k1_js_1 = require("@noble/curves/secp256k1.js");
const sha3_js_1 = require("@noble/hashes/sha3.js");
const rlp_1 = require("./rlp");
const encoding_1 = require("./encoding");
/** Converts a bigint to minimal big-endian bytes (no leading zeros). */
function bigintToBytes(n) {
    if (n === 0n)
        return new Uint8Array(0);
    let hex = n.toString(16);
    if (hex.length % 2 !== 0)
        hex = '0' + hex;
    return (0, encoding_1.hexToBytes)(hex);
}
/**
 * Builds the RLP-encoded EIP-1559 transaction payload (unsigned) for signing.
 *
 * Format: 0x02 || RLP([chainId, nonce, maxPriorityFeePerGas, maxFeePerGas,
 *                       gasLimit, to, value, data, accessList])
 */
function encodeUnsigned(tx) {
    const fields = [
        bigintToBytes(tx.chainId),
        bigintToBytes(tx.nonce),
        bigintToBytes(tx.maxPriorityFeePerGas),
        bigintToBytes(tx.maxFeePerGas),
        bigintToBytes(tx.gasLimit),
        (0, encoding_1.hexToBytes)(tx.to), // 20 bytes
        bigintToBytes(tx.value),
        tx.data === '0x' || tx.data === '' ? new Uint8Array(0) : (0, encoding_1.hexToBytes)(tx.data),
        [], // accessList — empty for simple transfers
    ];
    const rlp = (0, rlp_1.rlpEncode)(fields);
    // Prepend the EIP-2718 type byte (0x02).
    const envelope = new Uint8Array(1 + rlp.length);
    envelope[0] = 0x02;
    envelope.set(rlp, 1);
    return envelope;
}
/**
 * Signs an EIP-1559 transaction and returns the raw signed transaction hex
 * ready for broadcast (with `0x` prefix).
 *
 * @param tx - Transaction parameters.
 * @param privateKey - 32-byte private key.
 * @returns Signed raw transaction as a hex string with `0x` prefix.
 */
function signEip1559Transaction(tx, privateKey) {
    const unsigned = encodeUnsigned(tx);
    const hash = (0, sha3_js_1.keccak_256)(unsigned);
    // Sign with secp256k1. Use 'recovered' format to get [recovery, r, s].
    // prehash: false because we already hashed the payload ourselves.
    const sigBytes = secp256k1_js_1.secp256k1.sign(hash, privateKey, {
        prehash: false,
        lowS: true,
        format: 'recovered',
    });
    // 'recovered' format: 1 byte recovery || 32 bytes r || 32 bytes s = 65 bytes
    const recovery = sigBytes[0]; // 0 or 1
    const r = sigBytes.subarray(1, 33);
    const s = sigBytes.subarray(33, 65);
    // Strip leading zeros from r and s for RLP encoding.
    const rTrimmed = trimLeadingZeros(r);
    const sTrimmed = trimLeadingZeros(s);
    // Signed payload: 0x02 || RLP([chainId, nonce, maxPriorityFeePerGas, maxFeePerGas,
    //                               gasLimit, to, value, data, accessList, v, r, s])
    const fields = [
        bigintToBytes(tx.chainId),
        bigintToBytes(tx.nonce),
        bigintToBytes(tx.maxPriorityFeePerGas),
        bigintToBytes(tx.maxFeePerGas),
        bigintToBytes(tx.gasLimit),
        (0, encoding_1.hexToBytes)(tx.to),
        bigintToBytes(tx.value),
        tx.data === '0x' || tx.data === '' ? new Uint8Array(0) : (0, encoding_1.hexToBytes)(tx.data),
        [], // accessList
        bigintToBytes(BigInt(recovery)),
        rTrimmed,
        sTrimmed,
    ];
    const rlp = (0, rlp_1.rlpEncode)(fields);
    const signed = new Uint8Array(1 + rlp.length);
    signed[0] = 0x02;
    signed.set(rlp, 1);
    return '0x' + (0, encoding_1.bytesToHex)(signed);
}
/**
 * Signs a legacy (type-0) transaction and returns the raw signed transaction hex
 * ready for broadcast (with `0x` prefix).
 *
 * Uses EIP-155 replay protection.
 *
 * @param tx - Transaction parameters.
 * @param privateKey - 32-byte private key.
 * @returns Signed raw transaction as a hex string with `0x` prefix.
 */
function signLegacyTransaction(tx, privateKey) {
    // EIP-155 unsigned payload: RLP([nonce, gasPrice, gasLimit, to, value, data, chainId, 0, 0])
    const unsignedFields = [
        bigintToBytes(tx.nonce),
        bigintToBytes(tx.gasPrice),
        bigintToBytes(tx.gasLimit),
        (0, encoding_1.hexToBytes)(tx.to),
        bigintToBytes(tx.value),
        tx.data === '0x' || tx.data === '' ? new Uint8Array(0) : (0, encoding_1.hexToBytes)(tx.data),
        bigintToBytes(tx.chainId),
        new Uint8Array(0), // 0 for EIP-155
        new Uint8Array(0), // 0 for EIP-155
    ];
    const rlpUnsigned = (0, rlp_1.rlpEncode)(unsignedFields);
    const hash = (0, sha3_js_1.keccak_256)(rlpUnsigned);
    const sigBytes = secp256k1_js_1.secp256k1.sign(hash, privateKey, {
        prehash: false,
        lowS: true,
        format: 'recovered',
    });
    const recovery = sigBytes[0]; // 0 or 1
    const r = sigBytes.subarray(1, 33);
    const s = sigBytes.subarray(33, 65);
    // EIP-155: v = chainId * 2 + 35 + recovery
    const v = tx.chainId * 2n + 35n + BigInt(recovery);
    const signedFields = [
        bigintToBytes(tx.nonce),
        bigintToBytes(tx.gasPrice),
        bigintToBytes(tx.gasLimit),
        (0, encoding_1.hexToBytes)(tx.to),
        bigintToBytes(tx.value),
        tx.data === '0x' || tx.data === '' ? new Uint8Array(0) : (0, encoding_1.hexToBytes)(tx.data),
        bigintToBytes(v),
        trimLeadingZeros(r),
        trimLeadingZeros(s),
    ];
    const rlpSigned = (0, rlp_1.rlpEncode)(signedFields);
    return '0x' + (0, encoding_1.bytesToHex)(rlpSigned);
}
/** Removes leading zero bytes from a byte array. */
function trimLeadingZeros(bytes) {
    let i = 0;
    while (i < bytes.length - 1 && bytes[i] === 0)
        i++;
    return i === 0 ? bytes : bytes.subarray(i);
}