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chaingate

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A complete TypeScript library for connecting to and making transactions on different blockchains

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"use strict"; var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) { if (k2 === undefined) k2 = k; var desc = Object.getOwnPropertyDescriptor(m, k); if (!desc || ("get" in desc ? !m.__esModule : desc.writable || desc.configurable)) { desc = { enumerable: true, get: function() { return m[k]; } }; } Object.defineProperty(o, k2, desc); }) : (function(o, m, k, k2) { if (k2 === undefined) k2 = k; o[k2] = m[k]; })); var __setModuleDefault = (this && this.__setModuleDefault) || (Object.create ? (function(o, v) { Object.defineProperty(o, "default", { enumerable: true, value: v }); }) : function(o, v) { o["default"] = v; }); var __importStar = (this && this.__importStar) || (function () { var ownKeys = function(o) { ownKeys = Object.getOwnPropertyNames || function (o) { var ar = []; for (var k in o) if (Object.prototype.hasOwnProperty.call(o, k)) ar[ar.length] = k; return ar; }; return ownKeys(o); }; return function (mod) { if (mod && mod.__esModule) return mod; var result = {}; if (mod != null) for (var k = ownKeys(mod), i = 0; i < k.length; i++) if (k[i] !== "default") __createBinding(result, mod, k[i]); __setModuleDefault(result, mod); return result; }; })(); Object.defineProperty(exports, "__esModule", { value: true }); exports.signMessage = signMessage; exports.getSignedMessagePublicKey = getSignedMessagePublicKey; const secp = __importStar(require("@noble/secp256k1")); const sha256_1 = require("@noble/hashes/sha256"); function encodeVarInt(n) { if (n < 0xfd) { return Uint8Array.of(n); } else if (n <= 0xffff) { return Uint8Array.of(0xfd, n & 0xff, (n >> 8) & 0xff); } else if (n <= 0xffffffff) { return Uint8Array.of(0xfe, n & 0xff, (n >> 8) & 0xff, (n >> 16) & 0xff, (n >> 24) & 0xff); } else { throw new Error('Message too long'); } } function magicHash(message, prefix = '\x18Bitcoin Signed Message:\n') { const prefixBytes = new TextEncoder().encode(prefix); // Use byte length of prefix, not character length const prefixLen = encodeVarInt(prefixBytes.length); // Handle both string and Uint8Array message types let messageBytes; let msgLen; if (typeof message === 'string') { messageBytes = new TextEncoder().encode(message); // For strings, use the byte length (UTF-8 encoded length) msgLen = encodeVarInt(messageBytes.length); } else { messageBytes = message; msgLen = encodeVarInt(message.length); } const payload = new Uint8Array([...prefixLen, ...prefixBytes, ...msgLen, ...messageBytes]); return (0, sha256_1.sha256)((0, sha256_1.sha256)(payload)); } async function signMessage(message, privateKey, prefix = '\x18Bitcoin Signed Message:\n') { const hash = magicHash(message, prefix); // Sign with lowS option for canonical signatures const signature = await secp.signAsync(hash, privateKey.hex, { lowS: true }); // Get expected public key (compressed) const expectedPubKey = secp.getPublicKey(privateKey.hex, true); // Try each recovery ID to find the correct one for (let recoveryId = 0; recoveryId < 4; recoveryId++) { const recoveredPubKey = signature.addRecoveryBit(recoveryId).recoverPublicKey(hash); const recoveredBytes = recoveredPubKey.toRawBytes(true); // Compare the recovered public key with expected if (recoveredBytes.length === expectedPubKey.length && recoveredBytes.every((byte, i) => byte === expectedPubKey[i])) { const sigBytes = signature.toCompactRawBytes(); // Use 31 for compressed keys (Bitcoin standard) const recoveryFlag = 31 + recoveryId; const fullSig = new Uint8Array([recoveryFlag, ...sigBytes]); return btoa(String.fromCharCode(...fullSig)); } } throw new Error('Could not create recoverable signature'); } async function getSignedMessagePublicKey(message, signature, prefix = '\x18Bitcoin Signed Message:\n') { try { const hash = magicHash(message, prefix); // Decode base64 signature const sigBytes = Uint8Array.from(atob(signature), (c) => c.charCodeAt(0)); if (sigBytes.length !== 65) { throw new Error('Invalid signature length'); } const recoveryFlag = sigBytes[0]; const signatureData = sigBytes.slice(1); // Determine if compressed based on recovery flag const isCompressed = recoveryFlag >= 31; const recoveryId = isCompressed ? recoveryFlag - 31 : recoveryFlag - 27; if (recoveryId < 0 || recoveryId > 3) { throw new Error('Invalid recovery ID'); } // Create signature object const sig = secp.Signature.fromCompact(signatureData).addRecoveryBit(recoveryId); // Recover public key const recoveredPubKey = sig.recoverPublicKey(hash); return recoveredPubKey.toRawBytes(isCompressed); } catch (error) { if (error instanceof Error) { throw new Error(`Invalid signature: ${error.message}`); } throw new Error('Invalid signature'); } } //# sourceMappingURL=MessageSigner.js.map