/* A JavaScript implementation of the Secure Hash Algorithm, SHA-256
* Version 0.3 Copyright Angel Marin 2003-2004 - http://anmar.eu.org/
* Distributed under the BSD License
* Some bits taken from Paul Johnston's SHA-1 implementation
*/
var chrsz = 8;  /* bits per input character. 8 - ASCII; 16 - Unicode  */
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;
    /* append padding */
    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 binb2hex(binarray) {
    var hexcase = 0; /* hex output format. 0 - lowercase; 1 - uppercase */
    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;
}
function hex_sha256(s) {
    return binb2hex(core_sha256(str2binb(s), s.length * chrsz));
}