Node.js examples for Security:SHA
SHA-1 implementation in JavaScript
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ /* SHA-1 implementation in JavaScript (c) Chris Veness 2002-2009 */ /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ function sha1Hash(msg) { // constants [?4.2.1] var K = [0x5a827999, 0x6ed9eba1, 0x8f1bbcdc, 0xca62c1d6]; // PREPROCESSING msg += String.fromCharCode(0x80); // add trailing '1' bit (+ 0's padding) to string [?5.1.1] // convert string msg into 512-bit/16-integer blocks arrays of ints [?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-blocks required to hold 'l' ints var M = new Array(N); for (var i=0; i<N; i++) { M[i] = new Array(16);// w w w .j a v a 2 s . c om for (var j=0; j<16; j++) { // encode 4 chars per integer, big-endian encoding M[i][j] = (msg.charCodeAt(i*64+j*4)<<24) | (msg.charCodeAt(i*64+j*4+1)<<16) | (msg.charCodeAt(i*64+j*4+2)<<8) | (msg.charCodeAt(i*64+j*4+3)); } // 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 M[N-1][14] = ((msg.length-1)*8) / Math.pow(2, 32); M[N-1][14] = Math.floor(M[N-1][14]) M[N-1][15] = ((msg.length-1)*8) & 0xffffffff; // set initial hash value [?5.3.1] var H0 = 0x67452301; var H1 = 0xefcdab89; var H2 = 0x98badcfe; var H3 = 0x10325476; var H4 = 0xc3d2e1f0; // HASH COMPUTATION [?6.1.2] var W = new Array(80); var a, b, c, d, e; for (var i=0; i<N; i++) { // 1 - prepare message schedule 'W' for (var t=0; t<16; t++) W[t] = M[i][t]; for (var t=16; t<80; t++) W[t] = ROTL(W[t-3] ^ W[t-8] ^ W[t-14] ^ W[t-16], 1); // 2 - initialise five working variables a, b, c, d, e with previous hash value a = H0; b = H1; c = H2; d = H3; e = H4; // 3 - main loop for (var t=0; t<80; t++) { var s = Math.floor(t/20); // seq for blocks of 'f' functions and 'K' constants var T = (ROTL(a,5) + f(s,b,c,d) + e + K[s] + W[t]) & 0xffffffff; e = d; d = c; c = ROTL(b, 30); b = a; a = T; } // 4 - compute the new intermediate hash value H0 = (H0+a) & 0xffffffff; // note 'addition modulo 2^32' H1 = (H1+b) & 0xffffffff; H2 = (H2+c) & 0xffffffff; H3 = (H3+d) & 0xffffffff; H4 = (H4+e) & 0xffffffff; } return H0.toHexStr() + H1.toHexStr() + H2.toHexStr() + H3.toHexStr() + H4.toHexStr(); } // // function 'f' [?4.1.1] // function f(s, x, y, z) { switch (s) { case 0: return (x & y) ^ (~x & z); // Ch() case 1: return x ^ y ^ z; // Parity() case 2: return (x & y) ^ (x & z) ^ (y & z); // Maj() case 3: return x ^ y ^ z; // Parity() } } // // rotate left (circular left shift) value x by n positions [?3.2.5] // function ROTL(x, n) { return (x<<n) | (x>>>(32-n)); } // // extend Number class with a tailored hex-string method // (note toString(16) is implementation-dependant, and // in IE returns signed numbers when used on full words) // Number.prototype.toHexStr = function() { var s="", v; for (var i=7; i>=0; i--) { v = (this>>>(i*4)) & 0xf; s += v.toString(16); } return s; }