You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
92 lines
2.3 KiB
92 lines
2.3 KiB
/*
|
|
* A JavaScript implementation of the Secure Hash Algorithm, SHA-1, as defined
|
|
* in FIPS PUB 180-1
|
|
* Version 2.1a Copyright Paul Johnston 2000 - 2002.
|
|
* Other contributors: Greg Holt, Andrew Kepert, Ydnar, Lostinet
|
|
* Distributed under the BSD License
|
|
* See http://pajhome.org.uk/crypt/md5 for details.
|
|
*/
|
|
|
|
var helpers = require('./helpers');
|
|
|
|
/*
|
|
* Calculate the SHA-1 of an array of big-endian words, and a bit length
|
|
*/
|
|
function core_sha1(x, len) {
|
|
/* append padding */
|
|
x[len >> 5] |= 0x80 << (24 - (len % 32));
|
|
x[(((len + 64) >> 9) << 4) + 15] = len;
|
|
|
|
var w = Array(80);
|
|
var a = 1732584193;
|
|
var b = -271733879;
|
|
var c = -1732584194;
|
|
var d = 271733878;
|
|
var e = -1009589776;
|
|
|
|
for (var i = 0; i < x.length; i += 16) {
|
|
var olda = a;
|
|
var oldb = b;
|
|
var oldc = c;
|
|
var oldd = d;
|
|
var olde = e;
|
|
|
|
for (var j = 0; j < 80; j++) {
|
|
if (j < 16) w[j] = x[i + j];
|
|
else w[j] = rol(w[j - 3] ^ w[j - 8] ^ w[j - 14] ^ w[j - 16], 1);
|
|
var t = safe_add(safe_add(rol(a, 5), sha1_ft(j, b, c, d)), safe_add(safe_add(e, w[j]), sha1_kt(j)));
|
|
e = d;
|
|
d = c;
|
|
c = rol(b, 30);
|
|
b = a;
|
|
a = t;
|
|
}
|
|
|
|
a = safe_add(a, olda);
|
|
b = safe_add(b, oldb);
|
|
c = safe_add(c, oldc);
|
|
d = safe_add(d, oldd);
|
|
e = safe_add(e, olde);
|
|
}
|
|
return Array(a, b, c, d, e);
|
|
}
|
|
|
|
/*
|
|
* Perform the appropriate triplet combination function for the current
|
|
* iteration
|
|
*/
|
|
function sha1_ft(t, b, c, d) {
|
|
if (t < 20) return (b & c) | (~b & d);
|
|
if (t < 40) return b ^ c ^ d;
|
|
if (t < 60) return (b & c) | (b & d) | (c & d);
|
|
return b ^ c ^ d;
|
|
}
|
|
|
|
/*
|
|
* Determine the appropriate additive constant for the current iteration
|
|
*/
|
|
function sha1_kt(t) {
|
|
return t < 20 ? 1518500249 : t < 40 ? 1859775393 : t < 60 ? -1894007588 : -899497514;
|
|
}
|
|
|
|
/*
|
|
* Add integers, wrapping at 2^32. This uses 16-bit operations internally
|
|
* to work around bugs in some JS interpreters.
|
|
*/
|
|
function safe_add(x, y) {
|
|
var lsw = (x & 0xffff) + (y & 0xffff);
|
|
var msw = (x >> 16) + (y >> 16) + (lsw >> 16);
|
|
return (msw << 16) | (lsw & 0xffff);
|
|
}
|
|
|
|
/*
|
|
* Bitwise rotate a 32-bit number to the left.
|
|
*/
|
|
function rol(num, cnt) {
|
|
return (num << cnt) | (num >>> (32 - cnt));
|
|
}
|
|
|
|
module.exports = function sha1(buf) {
|
|
return helpers.hash(buf, core_sha1, 20, true);
|
|
};
|