antelope-ecc/mnemonic_recover.js

A universal JavaScript ECC digital signature and key utility package for Antelope based blockchains.

import words from "./internal/mnemonic-words.js";
/**
 * Recovers an antelope based private key from BIP39 mnemonic.
 *
 * @param recoveryPhrase 32 bytes of data.
 * import recoverMnemonic from "antelope-ecc/mnemonic-recover.js"
 *
 * recoverMnemonic([your, twenty, four, words, go, here, …]).then(console.log)
 * ```
 * The logged output was [abandon, busy, …].
 */
export default async function recoverMnemonic(recoveryPhrase) {
    recoveryPhrase = recoveryPhrase.normalize("NFKD").trim().toLowerCase();
    const ints = []; // Use a regular array to store the numbers.
    recoveryPhrase.split(/[\s,:-]+/gmu).forEach((word) => {
        let index = words.indexOf(word);
        if (index < 0)
            throw new Error(`unknown word: '${word}'`);
        ints.push(index);
    });
    let digits = ints.map((n) => n.toString(2).padStart(11, "0")).join("");
    let sumBitLen = Math.floor(digits.length / 32);
    let bitLen = digits.length - sumBitLen;
    let bytesArr = [];
    for (let bit = 0; bit < bitLen; bit += 8) {
        let bytestring = digits.slice(bit, bit + 8);
        let n = parseInt(bytestring, 2);
        if (n >= 0) {
            bytesArr.push(n);
        }
    }
    // the original random bytes used to generate the 12-24 words
    let entropyBytes = Uint8Array.from(bytesArr);
    return entropyBytes;
}