hd-utils/lib/utils/crypto/SHA256.js

A handy utils for modern JS developers

import utf8Encode from './utf8Encode';
export default function SHA256(data) {
    function rotateRight(n, x) {
        return (x >>> n) | (x << (32 - n));
    }
    function toHexString(byteArray) {
        return Array.from(byteArray, (byte) => {
            return ('0' + (byte & 0xff).toString(16)).slice(-2);
        }).join('');
    }
    const K = new Uint32Array([
        0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1,
        0x923f82a4, 0xab1c5ed5, 0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
        0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174, 0xe49b69c1, 0xefbe4786,
        0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
        0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147,
        0x06ca6351, 0x14292967, 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
        0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85, 0xa2bfe8a1, 0xa81a664b,
        0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
        0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a,
        0x5b9cca4f, 0x682e6ff3, 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
        0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2,
    ]);
    const byteArray = utf8Encode(data);
    const words = new Uint32Array(64);
    let length = byteArray.length * 8;
    // Padding
    byteArray[length >> 5] |= 0x80 << (24 - (length % 32));
    byteArray[(((length + 64) >> 9) << 4) + 15] = length;
    let a = 0x6a09e667;
    let b = 0xbb67ae85;
    let c = 0x3c6ef372;
    let d = 0xa54ff53a;
    let e = 0x510e527f;
    let f = 0x9b05688c;
    let g = 0x1f83d9ab;
    let h = 0x5be0cd19;
    for (let i = 0; i < byteArray.length; i += 64) {
        for (let j = 0; j < 16; j++) {
            words[j] =
                (byteArray[i + j * 4] << 24) |
                    (byteArray[i + j * 4 + 1] << 16) |
                    (byteArray[i + j * 4 + 2] << 8) |
                    byteArray[i + j * 4 + 3];
        }
        for (let j = 16; j < 64; j++) {
            const s0 = (rotateRight(2, words[j - 15]) ^
                rotateRight(13, words[j - 15]) ^
                rotateRight(22, words[j - 15])) >>>
                0;
            const s1 = (rotateRight(6, words[j - 2]) ^
                rotateRight(11, words[j - 2]) ^
                rotateRight(25, words[j - 2])) >>>
                0;
            words[j] = (words[j - 16] + s0 + words[j - 7] + s1) >>> 0;
            const ch = ((e & f) ^ (~e & g)) >>> 0;
            const temp1 = (h + s1 + ch + K[j] + words[j]) >>> 0;
            const maj = ((a & b) ^ (a & c) ^ (b & c)) >>> 0;
            const temp2 = (s0 + maj) >>> 0;
            h = g;
            g = f;
            f = e;
            e = (d + temp1) >>> 0;
            d = c;
            c = b;
            b = a;
            a = (temp1 + temp2) >>> 0;
        }
        a = (a + 0x6a09e667) >>> 0;
        b = (b + 0xbb67ae85) >>> 0;
        c = (c + 0x3c6ef372) >>> 0;
        d = (d + 0xa54ff53a) >>> 0;
        e = (e + 0x510e527f) >>> 0;
        f = (f + 0x9b05688c) >>> 0;
        g = (g + 0x1f83d9ab) >>> 0;
        h = (h + 0x5be0cd19) >>> 0;
    }
    // Concatenate the hash parts
    let hash = new Uint32Array([a, b, c, d, e, f, g, h]);
    let hashBytes = new Uint8Array(hash.buffer);
    return toHexString(hashBytes);
}