@s-ui/js
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Set of JS utilities
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JavaScript
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
/* SHA-256 (FIPS 180-4) implementation in JavaScript (c) Chris Veness 2002-2019 */
/* MIT Licence */
/* www.movable-type.co.uk/scripts/sha256.html */
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
/**
* SHA-256 hash function reference implementation.
*
* This is an annotated direct implementation of FIPS 180-4, without any optimisations. It is
* intended to aid understanding of the algorithm rather than for production use.
*
* While it could be used where performance is not critical, I would recommend using the ‘Web
* Cryptography API’ (developer.mozilla.org/en-US/docs/Web/API/SubtleCrypto/digest) for the browser,
* or the ‘crypto’ library (nodejs.org/api/crypto.html#crypto_class_hash) in Node.js.
*
* See csrc.nist.gov/groups/ST/toolkit/secure_hashing.html
* csrc.nist.gov/groups/ST/toolkit/examples.html
*/
var Sha256 = /*#__PURE__*/function () {
function Sha256() {}
/**
* Generates SHA-256 hash of string.
*
* @param {string} msg - (Unicode) string to be hashed.
* @param {Object} [options]
* @param {string} [options.msgFormat=string] - Message format: 'string' for JavaScript string
* (gets converted to UTF-8 for hashing); 'hex-bytes' for string of hex bytes ('616263' ≡ 'abc') .
* @param {string} [options.outFormat=hex] - Output format: 'hex' for string of contiguous
* hex bytes; 'hex-w' for grouping hex bytes into groups of (4 byte / 8 character) words.
* @returns {string} Hash of msg as hex character string.
*
* @example
* import Sha256 from './sha256.js';
* const hash = Sha256.hash('abc'); // 'ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad'
*/
Sha256.hash = function hash(msg, options) {
var defaults = {
msgFormat: 'string',
outFormat: 'hex'
};
var opt = Object.assign(defaults, options);
// note use throughout this routine of 'n >>> 0' to coerce Number 'n' to unsigned 32-bit integer
switch (opt.msgFormat) {
case 'hex-bytes':
msg = hexBytesToString(msg);
break;
// mostly for running tests
case 'string':
default:
// default is to convert string to UTF-8, as SHA only deals with byte-streams
msg = utf8Encode(msg);
}
// constants [§4.2.2]
var K = [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];
// initial hash value [§5.3.3]
var H = [0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a, 0x510e527f, 0x9b05688c, 0x1f83d9ab, 0x5be0cd19];
// PREPROCESSING [§6.2.1]
msg += String.fromCharCode(0x80); // add trailing '1' bit (+ 0's padding) to string [§5.1.1]
// convert string msg into 512-bit blocks (array of 16 32-bit integers) [§5.2.1]
var l = msg.length / 4 + 2; // length (in 32-bit integers) of msg + ‘1’ + appended length
var N = Math.ceil(l / 16); // number of 16-integer (512-bit) blocks required to hold 'l' ints
var M = new Array(N); // message M is N×16 array of 32-bit integers
for (var i = 0; i < N; i++) {
M[i] = new Array(16);
for (var j = 0; j < 16; j++) {
// encode 4 chars per integer (64 per block), big-endian encoding
M[i][j] = msg.charCodeAt(i * 64 + j * 4 + 0) << 24 | msg.charCodeAt(i * 64 + j * 4 + 1) << 16 | msg.charCodeAt(i * 64 + j * 4 + 2) << 8 | msg.charCodeAt(i * 64 + j * 4 + 3) << 0;
} // note running off the end of msg is ok 'cos bitwise ops on NaN return 0
}
// add length (in bits) into final pair of 32-bit integers (big-endian) [§5.1.1]
// note: most significant word would be (len-1)*8 >>> 32, but since JS converts
// bitwise-op args to 32 bits, we need to simulate this by arithmetic operators
var lenHi = (msg.length - 1) * 8 / Math.pow(2, 32);
var lenLo = (msg.length - 1) * 8 >>> 0;
M[N - 1][14] = Math.floor(lenHi);
M[N - 1][15] = lenLo;
// HASH COMPUTATION [§6.2.2]
for (var _i = 0; _i < N; _i++) {
var W = new Array(64);
// 1 - prepare message schedule 'W'
for (var t = 0; t < 16; t++) W[t] = M[_i][t];
for (var _t = 16; _t < 64; _t++) {
W[_t] = Sha256.σ1(W[_t - 2]) + W[_t - 7] + Sha256.σ0(W[_t - 15]) + W[_t - 16] >>> 0;
}
// 2 - initialise working variables a, b, c, d, e, f, g, h with previous hash value
var a = H[0];
var b = H[1];
var c = H[2];
var d = H[3];
var e = H[4];
var f = H[5];
var g = H[6];
var h = H[7];
// 3 - main loop (note '>>> 0' for 'addition modulo 2^32')
for (var _t2 = 0; _t2 < 64; _t2++) {
var T1 = h + Sha256.Σ1(e) + Sha256.Ch(e, f, g) + K[_t2] + W[_t2];
var T2 = Sha256.Σ0(a) + Sha256.Maj(a, b, c);
h = g;
g = f;
f = e;
e = d + T1 >>> 0;
d = c;
c = b;
b = a;
a = T1 + T2 >>> 0;
}
// 4 - compute the new intermediate hash value (note '>>> 0' for 'addition modulo 2^32')
H[0] = H[0] + a >>> 0;
H[1] = H[1] + b >>> 0;
H[2] = H[2] + c >>> 0;
H[3] = H[3] + d >>> 0;
H[4] = H[4] + e >>> 0;
H[5] = H[5] + f >>> 0;
H[6] = H[6] + g >>> 0;
H[7] = H[7] + h >>> 0;
}
// convert H0..H7 to hex strings (with leading zeros)
for (var _h = 0; _h < H.length; _h++) H[_h] = ('00000000' + H[_h].toString(16)).slice(-8);
// concatenate H0..H7, with separator if required
// eslint-disable-next-line eqeqeq
var separator = opt.outFormat == 'hex-w' ? ' ' : '';
return H.join(separator);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
function utf8Encode(str) {
try {
return new TextEncoder().encode(str, 'utf-8').reduce(function (prev, curr) {
return prev + String.fromCharCode(curr);
}, '');
} catch (e) {
// no TextEncoder available?
return unescape(encodeURIComponent(str)); // monsur.hossa.in/2012/07/20/utf-8-in-javascript.html
}
}
function hexBytesToString(hexStr) {
// convert string of hex numbers to a string of chars (eg '616263' -> 'abc').
var str = hexStr.replace(' ', ''); // allow space-separated groups
// eslint-disable-next-line eqeqeq
return str == '' ? '' : str.match(/.{2}/g).map(function (byte) {
return String.fromCharCode(parseInt(byte, 16));
}).join('');
}
}
/**
* Rotates right (circular right shift) value x by n positions [§3.2.4].
* @private
*/;
Sha256.ROTR = function ROTR(n, x) {
return x >>> n | x << 32 - n;
}
/**
* Logical functions [§4.1.2].
* @private
*/;
Sha256.Σ0 = function Σ0(x) {
return Sha256.ROTR(2, x) ^ Sha256.ROTR(13, x) ^ Sha256.ROTR(22, x);
};
Sha256.Σ1 = function Σ1(x) {
return Sha256.ROTR(6, x) ^ Sha256.ROTR(11, x) ^ Sha256.ROTR(25, x);
};
Sha256.σ0 = function σ0(x) {
return Sha256.ROTR(7, x) ^ Sha256.ROTR(18, x) ^ x >>> 3;
};
Sha256.σ1 = function σ1(x) {
return Sha256.ROTR(17, x) ^ Sha256.ROTR(19, x) ^ x >>> 10;
};
Sha256.Ch = function Ch(x, y, z) {
return x & y ^ ~x & z;
} // 'choice'
;
Sha256.Maj = function Maj(x, y, z) {
return x & y ^ x & z ^ y & z;
} // 'majority'
;
return Sha256;
}();
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
export default Sha256;