sdk_md5.js

/*
 * sdk的md5模块，提供一些md5的api
 *
 * create by zengxx on 2018-11-28
 */

let hexcase = 0;  /* hex output format. 0 - lowercase; 1 - uppercase        */
let b64pad  = ""; /* base-64 pad character. "=" for strict RFC compliance   */
let chrsz   = 8;  /* bits per input character. 8 - ASCII; 16 - Unicode      */

/*
 * Calculate the MD5 of an array of little-endian words, and a bit length
 */
let core_md5 = function (x, len) {
    /* 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)
    {
        let olda = a;
        let oldb = b;
        let oldc = c;
        let oldd = d;

        a = md5_ff(a, b, c, d, x[i+ 0], 7 , -680876936);
        d = md5_ff(d, a, b, c, x[i+ 1], 12, -389564586);
        c = md5_ff(c, d, a, b, x[i+ 2], 17,  606105819);
        b = md5_ff(b, c, d, a, x[i+ 3], 22, -1044525330);
        a = md5_ff(a, b, c, d, x[i+ 4], 7 , -176418897);
        d = md5_ff(d, a, b, c, x[i+ 5], 12,  1200080426);
        c = md5_ff(c, d, a, b, x[i+ 6], 17, -1473231341);
        b = md5_ff(b, c, d, a, x[i+ 7], 22, -45705983);
        a = md5_ff(a, b, c, d, x[i+ 8], 7 ,  1770035416);
        d = md5_ff(d, a, b, c, x[i+ 9], 12, -1958414417);
        c = md5_ff(c, d, a, b, x[i+10], 17, -42063);
        b = md5_ff(b, c, d, a, x[i+11], 22, -1990404162);
        a = md5_ff(a, b, c, d, x[i+12], 7 ,  1804603682);
        d = md5_ff(d, a, b, c, x[i+13], 12, -40341101);
        c = md5_ff(c, d, a, b, x[i+14], 17, -1502002290);
        b = md5_ff(b, c, d, a, x[i+15], 22,  1236535329);

        a = md5_gg(a, b, c, d, x[i+ 1], 5 , -165796510);
        d = md5_gg(d, a, b, c, x[i+ 6], 9 , -1069501632);
        c = md5_gg(c, d, a, b, x[i+11], 14,  643717713);
        b = md5_gg(b, c, d, a, x[i+ 0], 20, -373897302);
        a = md5_gg(a, b, c, d, x[i+ 5], 5 , -701558691);
        d = md5_gg(d, a, b, c, x[i+10], 9 ,  38016083);
        c = md5_gg(c, d, a, b, x[i+15], 14, -660478335);
        b = md5_gg(b, c, d, a, x[i+ 4], 20, -405537848);
        a = md5_gg(a, b, c, d, x[i+ 9], 5 ,  568446438);
        d = md5_gg(d, a, b, c, x[i+14], 9 , -1019803690);
        c = md5_gg(c, d, a, b, x[i+ 3], 14, -187363961);
        b = md5_gg(b, c, d, a, x[i+ 8], 20,  1163531501);
        a = md5_gg(a, b, c, d, x[i+13], 5 , -1444681467);
        d = md5_gg(d, a, b, c, x[i+ 2], 9 , -51403784);
        c = md5_gg(c, d, a, b, x[i+ 7], 14,  1735328473);
        b = md5_gg(b, c, d, a, x[i+12], 20, -1926607734);

        a = md5_hh(a, b, c, d, x[i+ 5], 4 , -378558);
        d = md5_hh(d, a, b, c, x[i+ 8], 11, -2022574463);
        c = md5_hh(c, d, a, b, x[i+11], 16,  1839030562);
        b = md5_hh(b, c, d, a, x[i+14], 23, -35309556);
        a = md5_hh(a, b, c, d, x[i+ 1], 4 , -1530992060);
        d = md5_hh(d, a, b, c, x[i+ 4], 11,  1272893353);
        c = md5_hh(c, d, a, b, x[i+ 7], 16, -155497632);
        b = md5_hh(b, c, d, a, x[i+10], 23, -1094730640);
        a = md5_hh(a, b, c, d, x[i+13], 4 ,  681279174);
        d = md5_hh(d, a, b, c, x[i+ 0], 11, -358537222);
        c = md5_hh(c, d, a, b, x[i+ 3], 16, -722521979);
        b = md5_hh(b, c, d, a, x[i+ 6], 23,  76029189);
        a = md5_hh(a, b, c, d, x[i+ 9], 4 , -640364487);
        d = md5_hh(d, a, b, c, x[i+12], 11, -421815835);
        c = md5_hh(c, d, a, b, x[i+15], 16,  530742520);
        b = md5_hh(b, c, d, a, x[i+ 2], 23, -995338651);

        a = md5_ii(a, b, c, d, x[i+ 0], 6 , -198630844);
        d = md5_ii(d, a, b, c, x[i+ 7], 10,  1126891415);
        c = md5_ii(c, d, a, b, x[i+14], 15, -1416354905);
        b = md5_ii(b, c, d, a, x[i+ 5], 21, -57434055);
        a = md5_ii(a, b, c, d, x[i+12], 6 ,  1700485571);
        d = md5_ii(d, a, b, c, x[i+ 3], 10, -1894986606);
        c = md5_ii(c, d, a, b, x[i+10], 15, -1051523);
        b = md5_ii(b, c, d, a, x[i+ 1], 21, -2054922799);
        a = md5_ii(a, b, c, d, x[i+ 8], 6 ,  1873313359);
        d = md5_ii(d, a, b, c, x[i+15], 10, -30611744);
        c = md5_ii(c, d, a, b, x[i+ 6], 15, -1560198380);
        b = md5_ii(b, c, d, a, x[i+13], 21,  1309151649);
        a = md5_ii(a, b, c, d, x[i+ 4], 6 , -145523070);
        d = md5_ii(d, a, b, c, x[i+11], 10, -1120210379);
        c = md5_ii(c, d, a, b, x[i+ 2], 15,  718787259);
        b = md5_ii(b, c, d, a, x[i+ 9], 21, -343485551);

        a = safe_add(a, olda);
        b = safe_add(b, oldb);
        c = safe_add(c, oldc);
        d = safe_add(d, oldd);
    }
    return Array(a, b, c, d);

};

/*
 * These functions implement the four basic operations the algorithm uses.
 */
let md5_cmn = function (q, a, b, x, s, t) {
    return safe_add(bit_rol(safe_add(safe_add(a, q), safe_add(x, t)), s),b);
};

let md5_ff = function (a, b, c, d, x, s, t) {
    return md5_cmn((b & c) | ((~b) & d), a, b, x, s, t);
}

let md5_gg = function (a, b, c, d, x, s, t) {
    return md5_cmn((b & d) | (c & (~d)), a, b, x, s, t);
}

let md5_hh = function (a, b, c, d, x, s, t) {
    return md5_cmn(b ^ c ^ d, a, b, x, s, t);
}

let md5_ii = function (a, b, c, d, x, s, t) {
    return md5_cmn(c ^ (b | (~d)), a, b, x, s, t);
}

/*
 * Calculate the HMAC-MD5, of a key and some data
 */
let core_hmac_md5 = function (key, data) {
    let bkey = str2binl(key);
    if(bkey.length > 16) bkey = core_md5(bkey, key.length * chrsz);

    let ipad = Array(16), opad = Array(16);
    for(let i = 0; i < 16; i++)
    {
        ipad[i] = bkey[i] ^ 0x36363636;
        opad[i] = bkey[i] ^ 0x5C5C5C5C;
    }

    let hash = core_md5(ipad.concat(str2binl(data)), 512 + data.length * chrsz);
    return core_md5(opad.concat(hash), 512 + 128);
}

/*
 * Add integers, wrapping at 2^32. This uses 16-bit operations internally
 * to work around bugs in some JS interpreters.
 */
let safe_add = function (x, y) {
    let lsw = (x & 0xFFFF) + (y & 0xFFFF);
    let msw = (x >> 16) + (y >> 16) + (lsw >> 16);
    return (msw << 16) | (lsw & 0xFFFF);
}

/*
 * Bitwise rotate a 32-bit number to the left.
 */
let bit_rol = function (num, cnt) {
    return (num << cnt) | (num >>> (32 - cnt));
}

/*
 * Convert a string to an array of little-endian words
 * If chrsz is ASCII, characters >255 have their hi-byte silently ignored.
 */
let str2binl = function (str) {
    let bin = Array();
    let mask = (1 << chrsz) - 1;
    for(let i = 0; i < str.length * chrsz; i += chrsz)
        bin[i>>5] |= (str.charCodeAt(i / chrsz) & mask) << (i%32);
    return bin;
}

/*
 * Convert an array of little-endian words to a string
 */
let binl2str = function (bin) {
    let str = "";
    let mask = (1 << chrsz) - 1;
    for(let i = 0; i < bin.length * 32; i += chrsz)
        str += String.fromCharCode((bin[i>>5] >>> (i % 32)) & mask);
    return str;
}

/*
 * Convert an array of little-endian words to a hex string.
 */
let binl2hex = function (binarray) {
    let hex_tab = hexcase ? "0123456789ABCDEF" : "0123456789abcdef";
    let str = "";
    for(let i = 0; i < binarray.length * 4; i++)
    {
        str += hex_tab.charAt((binarray[i>>2] >> ((i%4)*8+4)) & 0xF) +
            hex_tab.charAt((binarray[i>>2] >> ((i%4)*8  )) & 0xF);
    }
    return str;
}

/*
 * Convert an array of little-endian words to a base-64 string
 */
let binl2b64 = function (binarray) {
    let tab = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
    let str = "";
    for(let i = 0; i < binarray.length * 4; i += 3)
    {
        let triplet = (((binarray[i   >> 2] >> 8 * ( i   %4)) & 0xFF) << 16)
            | (((binarray[i+1 >> 2] >> 8 * ((i+1)%4)) & 0xFF) << 8 )
            |  ((binarray[i+2 >> 2] >> 8 * ((i+2)%4)) & 0xFF);
        for(let j = 0; j < 4; j++)
        {
            if(i * 8 + j * 6 > binarray.length * 32) str += b64pad;
            else str += tab.charAt((triplet >> 6*(3-j)) & 0x3F);
        }
    }
    return str;
}

// MD5 实例
let _instance = null;

class MD5 {
	static get instance () {
        if (!_instance) {
            _instance = new MD5();
        }

        return _instance;
    }

    constructor () {
    	
    }

    /*
     * These are the functions you'll usually want to call
     * They take string arguments and return either hex or base-64 encoded strings
     */
    
    hex_md5 (s) { return binl2hex(core_md5(str2binl(s), s.length * chrsz));};
    b64_md5 (s) { return binl2b64(core_md5(str2binl(s), s.length * chrsz));};
    str_md5 (s) { return binl2str(core_md5(str2binl(s), s.length * chrsz));};
    hex_hmac_md5 (key, data) { return binl2hex(core_hmac_md5(key, data)); };
    b64_hmac_md5 (key, data) { return binl2b64(core_hmac_md5(key, data)); };
    str_hmac_md5 (key, data) { return binl2str(core_hmac_md5(key, data)); };
}

module.exports = MD5.instance;