JS_前端加密方法sha256.js源码+用法

一、sha256.js

/**

 *

 * Secure Hash Algorithm (SHA256)

 * http://www.webtoolkit.info/

 *

 * Original code by Angel Marin, Paul Johnston.

 *

 **/

function SHA256(s){

    var chrsz = 8;

    var hexcase = 0;

    function safe_add (x, y) {

        var lsw = (x & 0xFFFF) + (y & 0xFFFF);

        var msw = (x >> 16) + (y >> 16) + (lsw >> 16);

        return (msw << 16) | (lsw & 0xFFFF);

    }

    function S (X, n) { return ( X >>> n ) | (X << (32 - n)); }

    function R (X, n) { return ( X >>> n ); }

    function Ch(x, y, z) { return ((x & y) ^ ((~x) & z)); }

    function Maj(x, y, z) { return ((x & y) ^ (x & z) ^ (y & z)); }

    function Sigma0256(x) { return (S(x, 2) ^ S(x, 13) ^ S(x, 22)); }

    function Sigma1256(x) { return (S(x, 6) ^ S(x, 11) ^ S(x, 25)); }

    function Gamma0256(x) { return (S(x, 7) ^ S(x, 18) ^ R(x, 3)); }

    function Gamma1256(x) { return (S(x, 17) ^ S(x, 19) ^ R(x, 10)); }

    function core_sha256 (m, l) {

        var K = new Array(0x428A2F98, 0x71374491, 0xB5C0FBCF, 0xE9B5DBA5, 0x3956C25B, 0x59F111F1, 0x923F82A4, 0xAB1C5ED5, 0xD807AA98, 0x12835B01, 0x243185BE, 0x550C7DC3, 0x72BE5D74, 0x80DEB1FE, 0x9BDC06A7, 0xC19BF174, 0xE49B69C1, 0xEFBE4786, 0xFC19DC6, 0x240CA1CC, 0x2DE92C6F, 0x4A7484AA, 0x5CB0A9DC, 0x76F988DA, 0x983E5152, 0xA831C66D, 0xB00327C8, 0xBF597FC7, 0xC6E00BF3, 0xD5A79147, 0x6CA6351, 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);

        var HASH = new Array(0x6A09E667, 0xBB67AE85, 0x3C6EF372, 0xA54FF53A, 0x510E527F, 0x9B05688C, 0x1F83D9AB, 0x5BE0CD19);

        var W = new Array(64);

        var a, b, c, d, e, f, g, h, i, j;

        var T1, T2;

        m[l >> 5] |= 0x80 << (24 - l % 32);

        m[((l + 64 >> 9) << 4) + 15] = l;

        for ( var i = 0; i<m.length; i+=16)
        {
        a = HASH[0];

        b = HASH[1];

        c = HASH[2];

        d = HASH[3];

        e = HASH[4];

        f = HASH[5];

        g = HASH[6];

        h = HASH[7];

        for ( var j = 0; j<64; j++) {

            if (j < 16) W[j] = m[j + i];

            else W[j] = safe_add(safe_add(safe_add(Gamma1256(W[j - 2]), W[j - 7]), Gamma0256(W[j - 15])), W[j - 16]);

            T1 = safe_add(safe_add(safe_add(safe_add(h, Sigma1256(e)), Ch(e, f, g)), K[j]), W[j]);

            T2 = safe_add(Sigma0256(a), Maj(a, b, c));

            h = g;

            g = f;

            f = e;

            e = safe_add(d, T1);

            d = c;

            c = b;

            b = a;

            a = safe_add(T1, T2);

        }

        HASH[0] = safe_add(a, HASH[0]);

        HASH[1] = safe_add(b, HASH[1]);

        HASH[2] = safe_add(c, HASH[2]);

        HASH[3] = safe_add(d, HASH[3]);

        HASH[4] = safe_add(e, HASH[4]);

        HASH[5] = safe_add(f, HASH[5]);

        HASH[6] = safe_add(g, HASH[6]);

        HASH[7] = safe_add(h, HASH[7]);

    }

    return HASH;

}

function str2binb (str) {

    var bin = Array();

    var mask = (1 << chrsz) - 1;

    for(var i = 0; i < str.length * chrsz; i += chrsz) {

        bin[i>>5] |= (str.charCodeAt(i / chrsz) & mask) << (24 - i%32);

    }

    return bin;

}

function Utf8Encode(string) {

    string = string.replace(/\r\n/g,"\n");

    var utftext = "";

    for (var n = 0; n < string.length; n++) {

        var c = string.charCodeAt(n);

        if (c < 128) {

            utftext += String.fromCharCode(c);

        }

        else if((c > 127) && (c < 2048)) {

            utftext += String.fromCharCode((c >> 6) | 192);

            utftext += String.fromCharCode((c & 63) | 128);

        }

        else {

            utftext += String.fromCharCode((c >> 12) | 224);

            utftext += String.fromCharCode(((c >> 6) & 63) | 128);

            utftext += String.fromCharCode((c & 63) | 128);

        }

    }

    return utftext;

}

function binb2hex (binarray) {

    var hex_tab = hexcase ? "0123456789ABCDEF" : "0123456789abcdef";

    var str = "";

    for(var i = 0; i < binarray.length * 4; i++) {

        str += hex_tab.charAt((binarray[i>>2] >> ((3 - i%4)*8+4)) & 0xF) +

            hex_tab.charAt((binarray[i>>2] >> ((3 - i%4)*8 )) & 0xF);

    }

    return str;

}

s = Utf8Encode(s);

return binb2hex(core_sha256(str2binb(s), s.length * chrsz));

}

二、使用方法

1.可以创建一个sha256.js文件，然后把上方的代码复制进去。
2.前端引入这个js，然后调用SHA256()方法即可。
3.下面是f12控制台里的测试结果

SHA256('555')