md5.ts

/*
 * JavaScript MD5
 * Adopted from https://github.com/blueimp/JavaScript-MD5
 *
 * Copyright 2011, Sebastian Tschan
 * https://blueimp.net
 *
 * Licensed under the MIT license:
 * https://opensource.org/licenses/MIT
 *
 * Based on
 * A JavaScript implementation of the RSA Data Security, Inc. MD5 Message
 * Digest Algorithm, as defined in RFC 1321.
 * Version 2.2 Copyright (C) Paul Johnston 1999 - 2009
 * Other contributors: Greg Holt, Andrew Kepert, Ydnar, Lostinet
 * Distributed under the BSD License
 * See http://pajhome.org.uk/crypt/md5 for more info.
 */

/**
 * Add integers, wrapping at 2^32.
 * This uses 16-bit operations internally to work around bugs in interpreters.
 *
 * @param x First integer
 * @param y Second integer
 * @returns Sum
 */
function safeAdd(x: number, y: number): number {
	const lsw = (x & 0xffff) + (y & 0xffff);
	const msw = (x >> 16) + (y >> 16) + (lsw >> 16);

	return (msw << 16) | (lsw & 0xffff);
}

/**
 * Bitwise rotate a 32-bit number to the left.
 *
 * @param num 32-bit number
 * @param cnt Rotation count
 * @returns  Rotated number
 */
function bitRotateLeft(num: number, cnt: number): number {
	return (num << cnt) | (num >>> (32 - cnt));
}

/**
 * Basic operation the algorithm uses.
 *
 * @param q q
 * @param a a
 * @param b b
 * @param x x
 * @param s s
 * @param t t
 * @returns Result
 */
function md5cmn(
	q: number,
	a: number,
	b: number,
	x: number,
	s: number,
	t: number
): number {
	return safeAdd(bitRotateLeft(safeAdd(safeAdd(a, q), safeAdd(x, t)), s), b);
}
/**
 * Basic operation the algorithm uses.
 *
 * @param a a
 * @param b b
 * @param c c
 * @param d d
 * @param x x
 * @param s s
 * @param t t
 * @returns Result
 */
function md5ff(
	a: number,
	b: number,
	c: number,
	d: number,
	x: number,
	s: number,
	t: number
): number {
	return md5cmn((b & c) | (~b & d), a, b, x, s, t);
}
/**
 * Basic operation the algorithm uses.
 *
 * @param a a
 * @param b b
 * @param c c
 * @param d d
 * @param x x
 * @param s s
 * @param t t
 * @returns Result
 */
function md5gg(
	a: number,
	b: number,
	c: number,
	d: number,
	x: number,
	s: number,
	t: number
): number {
	return md5cmn((b & d) | (c & ~d), a, b, x, s, t);
}
/**
 * Basic operation the algorithm uses.
 *
 * @param a a
 * @param b b
 * @param c c
 * @param d d
 * @param x x
 * @param s s
 * @param t t
 * @returns Result
 */
function md5hh(
	a: number,
	b: number,
	c: number,
	d: number,
	x: number,
	s: number,
	t: number
): number {
	return md5cmn(b ^ c ^ d, a, b, x, s, t);
}
/**
 * Basic operation the algorithm uses.
 *
 * @param a a
 * @param b b
 * @param c c
 * @param d d
 * @param x x
 * @param s s
 * @param t t
 * @returns Result
 */
function md5ii(
	a: number,
	b: number,
	c: number,
	d: number,
	x: number,
	s: number,
	t: number
): number {
	return md5cmn(c ^ (b | ~d), a, b, x, s, t);
}

/**
 * Calculate the MD5 of an array of little-endian words, and a bit length.
 *
 * @param x Array of little-endian words
 * @param len Bit length
 * @returns MD5 Array
 */
function binlMD5(x: number[], len: number): number[] {
	/* append padding */
	x[len >> 5] |= 0x80 << len % 32;
	x[(((len + 64) >>> 9) << 4) + 14] = len;

	let a = 1732584193;
	let b = -271733879;
	let c = -1732584194;
	let d = 271733878;

	for (let i = 0; i < x.length; i += 16) {
		const olda = a;
		const oldb = b;
		const oldc = c;
		const oldd = d;

		a = md5ff(a, b, c, d, x[i], 7, -680876936);
		d = md5ff(d, a, b, c, x[i + 1], 12, -389564586);
		c = md5ff(c, d, a, b, x[i + 2], 17, 606105819);
		b = md5ff(b, c, d, a, x[i + 3], 22, -1044525330);
		a = md5ff(a, b, c, d, x[i + 4], 7, -176418897);
		d = md5ff(d, a, b, c, x[i + 5], 12, 1200080426);
		c = md5ff(c, d, a, b, x[i + 6], 17, -1473231341);
		b = md5ff(b, c, d, a, x[i + 7], 22, -45705983);
		a = md5ff(a, b, c, d, x[i + 8], 7, 1770035416);
		d = md5ff(d, a, b, c, x[i + 9], 12, -1958414417);
		c = md5ff(c, d, a, b, x[i + 10], 17, -42063);
		b = md5ff(b, c, d, a, x[i + 11], 22, -1990404162);
		a = md5ff(a, b, c, d, x[i + 12], 7, 1804603682);
		d = md5ff(d, a, b, c, x[i + 13], 12, -40341101);
		c = md5ff(c, d, a, b, x[i + 14], 17, -1502002290);
		b = md5ff(b, c, d, a, x[i + 15], 22, 1236535329);

		a = md5gg(a, b, c, d, x[i + 1], 5, -165796510);
		d = md5gg(d, a, b, c, x[i + 6], 9, -1069501632);
		c = md5gg(c, d, a, b, x[i + 11], 14, 643717713);
		b = md5gg(b, c, d, a, x[i], 20, -373897302);
		a = md5gg(a, b, c, d, x[i + 5], 5, -701558691);
		d = md5gg(d, a, b, c, x[i + 10], 9, 38016083);
		c = md5gg(c, d, a, b, x[i + 15], 14, -660478335);
		b = md5gg(b, c, d, a, x[i + 4], 20, -405537848);
		a = md5gg(a, b, c, d, x[i + 9], 5, 568446438);
		d = md5gg(d, a, b, c, x[i + 14], 9, -1019803690);
		c = md5gg(c, d, a, b, x[i + 3], 14, -187363961);
		b = md5gg(b, c, d, a, x[i + 8], 20, 1163531501);
		a = md5gg(a, b, c, d, x[i + 13], 5, -1444681467);
		d = md5gg(d, a, b, c, x[i + 2], 9, -51403784);
		c = md5gg(c, d, a, b, x[i + 7], 14, 1735328473);
		b = md5gg(b, c, d, a, x[i + 12], 20, -1926607734);

		a = md5hh(a, b, c, d, x[i + 5], 4, -378558);
		d = md5hh(d, a, b, c, x[i + 8], 11, -2022574463);
		c = md5hh(c, d, a, b, x[i + 11], 16, 1839030562);
		b = md5hh(b, c, d, a, x[i + 14], 23, -35309556);
		a = md5hh(a, b, c, d, x[i + 1], 4, -1530992060);
		d = md5hh(d, a, b, c, x[i + 4], 11, 1272893353);
		c = md5hh(c, d, a, b, x[i + 7], 16, -155497632);
		b = md5hh(b, c, d, a, x[i + 10], 23, -1094730640);
		a = md5hh(a, b, c, d, x[i + 13], 4, 681279174);
		d = md5hh(d, a, b, c, x[i], 11, -358537222);
		c = md5hh(c, d, a, b, x[i + 3], 16, -722521979);
		b = md5hh(b, c, d, a, x[i + 6], 23, 76029189);
		a = md5hh(a, b, c, d, x[i + 9], 4, -640364487);
		d = md5hh(d, a, b, c, x[i + 12], 11, -421815835);
		c = md5hh(c, d, a, b, x[i + 15], 16, 530742520);
		b = md5hh(b, c, d, a, x[i + 2], 23, -995338651);

		a = md5ii(a, b, c, d, x[i], 6, -198630844);
		d = md5ii(d, a, b, c, x[i + 7], 10, 1126891415);
		c = md5ii(c, d, a, b, x[i + 14], 15, -1416354905);
		b = md5ii(b, c, d, a, x[i + 5], 21, -57434055);
		a = md5ii(a, b, c, d, x[i + 12], 6, 1700485571);
		d = md5ii(d, a, b, c, x[i + 3], 10, -1894986606);
		c = md5ii(c, d, a, b, x[i + 10], 15, -1051523);
		b = md5ii(b, c, d, a, x[i + 1], 21, -2054922799);
		a = md5ii(a, b, c, d, x[i + 8], 6, 1873313359);
		d = md5ii(d, a, b, c, x[i + 15], 10, -30611744);
		c = md5ii(c, d, a, b, x[i + 6], 15, -1560198380);
		b = md5ii(b, c, d, a, x[i + 13], 21, 1309151649);
		a = md5ii(a, b, c, d, x[i + 4], 6, -145523070);
		d = md5ii(d, a, b, c, x[i + 11], 10, -1120210379);
		c = md5ii(c, d, a, b, x[i + 2], 15, 718787259);
		b = md5ii(b, c, d, a, x[i + 9], 21, -343485551);

		a = safeAdd(a, olda);
		b = safeAdd(b, oldb);
		c = safeAdd(c, oldc);
		d = safeAdd(d, oldd);
	}

	return [a, b, c, d];
}

/**
 * Convert an array of little-endian words to a string
 *
 * @param input MD5 Array
 * @returns MD5 string
 */
function binl2rstr(input: number[]): string {
	let output = "";
	const length32 = input.length * 32;
	for (let i = 0; i < length32; i += 8) {
		output += String.fromCharCode((input[i >> 5] >>> i % 32) & 0xff);
	}

	return output;
}

/**
 * Convert a raw string to an array of little-endian words
 * Characters >255 have their high-byte silently ignored.
 *
 * @param input Raw input string
 * @returns Array of little-endian words
 */
function rstr2binl(input: string): number[] {
	const output: number[] = [];
	const outputLen = input.length >> 2;
	for (let i = 0; i < outputLen; i += 1) {
		output[i] = 0;
	}
	const length8 = input.length * 8;
	for (let i = 0; i < length8; i += 8) {
		output[i >> 5]! |= (input.charCodeAt(i / 8) & 0xff) << i % 32;
	}

	return <number[]>output;
}

/**
 * Calculate the MD5 of a raw string
 *
 * @param s Input string
 * @returns Raw MD5 string
 */
function rstrMD5(s: string): string {
	return binl2rstr(binlMD5(rstr2binl(s), s.length * 8));
}

/**
 * Calculates the HMAC-MD5 of a key and some data (raw strings)
 *
 * @param key HMAC key
 * @param data Raw input string
 * @returns Raw MD5 string
 */
function rstrHMACMD5(key: string, data: string): string {
	let bkey = rstr2binl(key);
	const ipad: number[] = [];
	const opad: number[] = [];
	if (bkey.length > 16) {
		bkey = binlMD5(bkey, key.length * 8);
	}
	for (let i = 0; i < 16; i += 1) {
		ipad[i] = bkey[i] ^ 0x36363636;
		opad[i] = bkey[i] ^ 0x5c5c5c5c;
	}
	const hash = binlMD5(ipad.concat(rstr2binl(data)), 512 + data.length * 8);

	return binl2rstr(binlMD5(opad.concat(hash), 512 + 128));
}

/**
 * Convert a raw string to a hex string
 *
 * @param input Raw input string
 * @returns Hex encoded string
 */
function rstr2hex(input: string): string {
	const hexTab = "0123456789abcdef";
	let output = "";
	for (let i = 0; i < input.length; i += 1) {
		const x = input.charCodeAt(i);
		output += hexTab.charAt((x >>> 4) & 0x0f) + hexTab.charAt(x & 0x0f);
	}

	return output;
}

/**
 * Encode a string as UTF-8
 *
 * @param input Input string
 * @returns UTF8 string
 */
function str2rstrUTF8(input: string): string {
	return unescape(encodeURIComponent(input));
}

/**
 * Encodes input string as raw MD5 string
 *
 * @param s Input string
 * @returns Raw MD5 string
 */
function rawMD5(s: string): string {
	return rstrMD5(str2rstrUTF8(s));
}
/**
 * Encodes input string as Hex encoded string
 *
 * @param s Input string
 * @returns Hex encoded string
 */
function hexMD5(s: string): string {
	return rstr2hex(rawMD5(s));
}
/**
 * Calculates the raw HMAC-MD5 for the given key and data
 *
 * @param k HMAC key
 * @param d Input string
 * @returns Raw MD5 string
 */
function rawHMACMD5(k: string, d: string): string {
	return rstrHMACMD5(str2rstrUTF8(k), str2rstrUTF8(d));
}
/**
 * Calculates the Hex encoded HMAC-MD5 for the given key and data
 *
 * @param k HMAC key
 * @param d Input string
 * @returns Raw MD5 string
 */
function hexHMACMD5(k: string, d: string): string {
	return rstr2hex(rawHMACMD5(k, d));
}

/**
 * Calculates MD5 value for a given string.
 * If a key is provided, calculates the HMAC-MD5 value.
 * Returns a Hex encoded string unless the raw argument is given.
 *
 * @param string Input string
 * @param key HMAC key
 * @param raw Raw output switch
 * @returns MD5 output
 */
export default function md5(
	string: string,
	key?: string,
	raw?: boolean
): string {
	if (!key) {
		if (!raw) {
			return hexMD5(string);
		}

		return rawMD5(string);
	}
	if (!raw) {
		return hexHMACMD5(key, string);
	}

	return rawHMACMD5(key, string);
}