Nate
Reputation: 2047
Can you identify this hash function written in javascript?
Can anyone identify this hash function? It is written in Javascript. I would like to duplicate it in another language (PHP). I would find it hard to believe that a function as tedious as this was written by a human. The function is called "cValue"... maybe that will help. Thanks in advance!
function (s) {
function L(b, a) {
return (b << a) | (b >>> (32 - a))
}
function K(k, b) {
var F, a, d, x, c;
d = (k & 2147483648);
x = (b & 2147483648);
F = (k & 1073741824);
a = (b & 1073741824);
c = (k & 1073741823) + (b & 1073741823);
if (F & a) {
return (c ^ 2147483648 ^ d ^ x)
}
if (F | a) {
if (c & 1073741824) {
return (c ^ 3221225472 ^ d ^ x)
} else {
return (c ^ 1073741824 ^ d ^ x)
}
} else {
return (c ^ d ^ x)
}
}
function r(a, c, b) {
return (a & c) | ((~a) & b)
}
function q(a, c, b) {
return (a & b) | (c & (~b))
}
function p(a, c, b) {
return (a ^ c ^ b)
}
function n(a, c, b) {
return (c ^ (a | (~b)))
}
function u(G, F, aa, Z, k, H, I) {
G = K(G, K(K(r(F, aa, Z), k), I));
return K(L(G, H), F)
}
function f(G, F, aa, Z, k, H, I) {
G = K(G, K(K(q(F, aa, Z), k), I));
return K(L(G, H), F)
}
function D(G, F, aa, Z, k, H, I) {
G = K(G, K(K(p(F, aa, Z), k), I));
return K(L(G, H), F)
}
function t(G, F, aa, Z, k, H, I) {
G = K(G, K(K(n(F, aa, Z), k), I));
return K(L(G, H), F)
}
function e(k) {
var G;
var d = k.length;
var c = d + 8;
var b = (c - (c % 64)) / 64;
var F = (b + 1) * 16;
var H = Array(F - 1);
var a = 0;
var x = 0;
while (x < d) {
G = (x - (x % 4)) / 4;
a = (x % 4) * 8;
H[G] = (H[G] | (k.charCodeAt(x) << a));
x++
}
G = (x - (x % 4)) / 4;
a = (x % 4) * 8;
H[G] = H[G] | (128 << a);
H[F - 2] = d << 3;
H[F - 1] = d >>> 29;
return H
}
function B(c) {
var b = "",
d = "",
k, a;
for (a = 0; a <= 3; a++) {
k = (c >>> (a * 8)) & 255;
d = "0" + k.toString(16);
b = b + d.substr(d.length - 2, 2)
}
return b
}
function J(b) {
b = b.replace(/\r\n/g, "\n");
var a = "";
for (var k = 0; k < b.length; k++) {
var d = b.charCodeAt(k);
if (d < 128) {
a += String.fromCharCode(d)
} else {
if ((d > 127) && (d < 2048)) {
a += String.fromCharCode((d >> 6) | 192);
a += String.fromCharCode((d & 63) | 128)
} else {
a += String.fromCharCode((d >> 12) | 224);
a += String.fromCharCode(((d >> 6) & 63) | 128);
a += String.fromCharCode((d & 63) | 128)
}
}
}
return a
}
var C = Array();
var P, h, E, v, g, Y, X, W, V;
var S = 7,
Q = 12,
N = 17,
M = 22;
var A = 5,
z = 9,
y = 14,
w = 20;
var o = 4,
m = 11,
l = 16,
j = 23;
var U = 6,
T = 10,
R = 15,
O = 21;
s = J(s);
C = e(s);
Y = 1732584193;
X = 4023233417;
W = 2562383102;
V = 271733878;
for (P = 0; P < C.length; P += 16) {
h = Y;
E = X;
v = W;
g = V;
Y = u(Y, X, W, V, C[P + 0], S, 3614090360);
V = u(V, Y, X, W, C[P + 1], Q, 3905402710);
W = u(W, V, Y, X, C[P + 2], N, 606105819);
X = u(X, W, V, Y, C[P + 3], M, 3250441966);
Y = u(Y, X, W, V, C[P + 4], S, 4118548399);
V = u(V, Y, X, W, C[P + 5], Q, 1200080426);
W = u(W, V, Y, X, C[P + 6], N, 2821735955);
X = u(X, W, V, Y, C[P + 7], M, 4249261313);
Y = u(Y, X, W, V, C[P + 8], S, 1770035416);
V = u(V, Y, X, W, C[P + 9], Q, 2336552879);
W = u(W, V, Y, X, C[P + 10], N, 4294925233);
X = u(X, W, V, Y, C[P + 11], M, 2304563134);
Y = u(Y, X, W, V, C[P + 12], S, 1804603682);
V = u(V, Y, X, W, C[P + 13], Q, 4254626195);
W = u(W, V, Y, X, C[P + 14], N, 2792965006);
X = u(X, W, V, Y, C[P + 15], M, 1236535329);
Y = f(Y, X, W, V, C[P + 1], A, 4129170786);
V = f(V, Y, X, W, C[P + 6], z, 3225465664);
W = f(W, V, Y, X, C[P + 11], y, 643717713);
X = f(X, W, V, Y, C[P + 0], w, 3921069994);
Y = f(Y, X, W, V, C[P + 5], A, 3593408605);
V = f(V, Y, X, W, C[P + 10], z, 38016083);
W = f(W, V, Y, X, C[P + 15], y, 3634488961);
X = f(X, W, V, Y, C[P + 4], w, 3889429448);
Y = f(Y, X, W, V, C[P + 9], A, 568446438);
V = f(V, Y, X, W, C[P + 14], z, 3275163606);
W = f(W, V, Y, X, C[P + 3], y, 4107603335);
X = f(X, W, V, Y, C[P + 8], w, 1163531501);
Y = f(Y, X, W, V, C[P + 13], A, 2850285829);
V = f(V, Y, X, W, C[P + 2], z, 4243563512);
W = f(W, V, Y, X, C[P + 7], y, 1735328473);
X = f(X, W, V, Y, C[P + 12], w, 2368359562);
Y = D(Y, X, W, V, C[P + 5], o, 4294588738);
V = D(V, Y, X, W, C[P + 8], m, 2272392833);
W = D(W, V, Y, X, C[P + 11], l, 1839030562);
X = D(X, W, V, Y, C[P + 14], j, 4259657740);
Y = D(Y, X, W, V, C[P + 1], o, 2763975236);
V = D(V, Y, X, W, C[P + 4], m, 1272893353);
W = D(W, V, Y, X, C[P + 7], l, 4139469664);
X = D(X, W, V, Y, C[P + 10], j, 3200236656);
Y = D(Y, X, W, V, C[P + 13], o, 681279174);
V = D(V, Y, X, W, C[P + 0], m, 3936430074);
W = D(W, V, Y, X, C[P + 3], l, 3572445317);
X = D(X, W, V, Y, C[P + 6], j, 76029189);
Y = D(Y, X, W, V, C[P + 9], o, 3654602809);
V = D(V, Y, X, W, C[P + 12], m, 3873151461);
W = D(W, V, Y, X, C[P + 15], l, 530742520);
X = D(X, W, V, Y, C[P + 2], j, 3299628645);
Y = t(Y, X, W, V, C[P + 0], U, 4096336452);
V = t(V, Y, X, W, C[P + 7], T, 1126891415);
W = t(W, V, Y, X, C[P + 14], R, 2878612391);
X = t(X, W, V, Y, C[P + 5], O, 4237533241);
Y = t(Y, X, W, V, C[P + 12], U, 1700485571);
V = t(V, Y, X, W, C[P + 3], T, 2399980690);
W = t(W, V, Y, X, C[P + 10], R, 4293915773);
X = t(X, W, V, Y, C[P + 1], O, 2240044497);
Y = t(Y, X, W, V, C[P + 8], U, 1873313359);
V = t(V, Y, X, W, C[P + 15], T, 4264355552);
W = t(W, V, Y, X, C[P + 6], R, 2734768916);
X = t(X, W, V, Y, C[P + 13], O, 1309151649);
Y = t(Y, X, W, V, C[P + 4], U, 4149444226);
V = t(V, Y, X, W, C[P + 11], T, 3174756917);
W = t(W, V, Y, X, C[P + 2], R, 718787259);
X = t(X, W, V, Y, C[P + 9], O, 3951481745);
Y = K(Y, h);
X = K(X, E);
W = K(W, v);
V = K(V, g)
}
var i = B(Y) + B(X) + B(W) + B(V);
return i.toLowerCase()
};
Upvotes: 2
Views: 571
Answers (4)
Hoverboard2525
Reputation: 1
This hash function is MD5. As shown in the for (P = 0; P < C.length; P+=16) loop, it features MD5 compression, repeating the u/f/d/t/k functions.
Upvotes: 0
jcubic
Reputation: 66490
MD5 call this function with simple string, get hash and go to this site: http://www.onlinehashcrack.com/free-hash-reverse.php
Upvotes: 0
jordancpaul
Reputation: 2964
Due to the use of XOR in function K() and the multi-stage process of calling functions which all use K(), my best guess is that this is an implementation of some cryptographic algorithm. Also, since there only seems to be one multi-stage function, it is likely to be some form of hash-generator such as MD5
Upvotes: 0
Pascal MARTIN
Reputation: 401002
Defining this function as a() :
var a = /* what you posted */
And calling the following :
a('test');
a('plop');
a('this is another test just to be sure');
I get the three following results :
098f6bcd4621d373cade4e832627b4f6
64a4e8faed1a1aa0bf8bf0fc84938d25
17733df129ee53bd321a323b0ae55401
A 32 characters long string immediatly looks like a [**md5 hash**][1] ; but let's verify a bit more.
Calling this in PHP :
var_dump(md5('test'));
var_dump(md5('plop'));
var_dump(md5('this is another test just to be sure'));
I get the following output :
string '098f6bcd4621d373cade4e832627b4f6' (length=32)
string '64a4e8faed1a1aa0bf8bf0fc84938d25' (length=32)
string '17733df129ee53bd321a323b0ae55401' (length=32)
Which are the three exact same results.
Of course, only three tests are not much, and you should do a couple more to be sure... But, as far as I cant tell, your function seems to be calculating a md5 hash -- and the corresponding PHP function is [**`md5()`**][2] ;-)
Upvotes: 8
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