1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
|
srp.Constants = function() {
// Variables used in the SRP protocol
var Nstr = "eeaf0ab9adb38dd69c33f80afa8fc5e86072618775ff3c0b9ea2314c9c256576d674df7496ea81d3383b4813d692c6e0e0d5d8e250b98be48e495c1d6089dad15dc7d7b46154d6b6ce8ef4ad69b15d4982559b297bcf1885c529f566660e57ec68edbc3c05726cc02fd4cbf4976eaa9afd5138fe8376435b9fc61d2fc0eb06e3";
var N = new BigInteger(Nstr, 16);
var g = new BigInteger("2");
var k = new BigInteger("bf66c44a428916cad64aa7c679f3fd897ad4c375e9bbb4cbf2f5de241d618ef0", 16);
var rng = new SecureRandom();
this.calcA = function(_a) {
a = new BigInteger(_a, 16);
return g.modPow(a, N).toString(16);
};
// Calculates the X value
// x = H(s, H(I:p))
this.calcX = function(login, password, salt) {
var salted = salt + SHA256(login + ":" + password)
return SHA256(hex2a(salted));
};
this.calcV = this.calcA;
// u = H(A,B)
this.calcU = function(A, B) {
return SHA256(hex2a(A + B));
};
//S = (B - kg^x) ^ (a + ux)
this.calcS = function(_a, _A, _B, _x) {
var a = new BigInteger(_a, 16);
var x = new BigInteger(_x, 16);
var u = new BigInteger(this.calcU(_A, _B), 16);
var B = new BigInteger(_B, 16);
var kgx = k.multiply(g.modPow(x, N));
var aux = a.add(u.multiply(x));
return B.subtract(kgx).modPow(aux, N).toString(16);
}
this.calcK = function(_S) {
return SHA256(hex2a(_S));
}
this.nXorG = function() {
var hashN = SHA256(hex2a(Nstr));
var hashG = SHA256(hex2a(g.toString(16)));
return hexXor(hashN, hashG);
};
this.hash = function(hexString) {
return removeLeading0(SHA256(hex2a(hexString)));
};
this.isInvalidEphemeral = function(a) {
return (g.modPow(a, N) == 0);
};
this.randomEphemeral = function() {
var a = new BigInteger(32, rng);
while(this.isInvalidEphemeral(a))
{
a = new BigInteger(32, rng);
}
return a.toString(16);
};
// some 16 byte random number
this.randomSalt = function() {
return new BigInteger(64, rng).toString(16);
}
function hex2a(hex) {
var str = '';
if(hex.length % 2) {
hex = "0" + hex;
}
for (var i = 0; i < hex.length; i += 2)
str += String.fromCharCode(parseInt(hex.substr(i, 2), 16));
return str;
}
function removeLeading0(hex) {
if (hex[0] == "0") {
return hex.substr(1);
} else {
return hex;
}
}
function hexXor(a, b) {
var str = '';
for (var i = 0; i < a.length; i += 2) {
var xor = parseInt(a.substr(i, 2), 16) ^ parseInt(b.substr(i, 2), 16)
xor = xor.toString(16);
str += (xor.length == 1) ? ("0" + xor) : xor
}
return str;
}
};
|
