bintzwing/core/srp.js
2011-04-19 16:26:59 -07:00

98 lines
3.2 KiB
JavaScript

/** @fileOverview Javascript SRP implementation.
*
* @author Quinn Slack
*/
/**
* Compute the SRP verifier from the username, password, salt, and group.
* @class SRP
*/
sjcl.keyexchange.srp = {
makeVerifier: function(I, P, s, group) {
var x;
// From RFC 5054:
// v = g^x mod N
x = this.makeX(I, P, s);
x = sjcl.bn.fromBits(x);
return group.g.powermod(x, group.N);
},
/**
* Calculates SRP x.
* x = SHA1(<salt> | SHA(<username> | ":" | <raw password>)) [RFC 2945]
* @param {String} I The username.
* @param {String} P The password.
* @param {Object} s A bitArray of the salt.
* @return {Object} A bitArray of SRP x.
*/
makeX: function(I, P, s) {
var inner = sjcl.hash.sha1.hash(I + ':' + P);
return sjcl.hash.sha1.hash(sjcl.bitArray.concat(s, inner));
},
/**
* Returns the known SRP group with the given size (in bits).
* @param {String} i The size of the known SRP group.
* @return {Object} An object with "N" and "g" properties.
*/
knownGroup:function(i) {
if (typeof i !== "string") { i = i.toString(); }
if (!this._didInitKnownGroups) { this._initKnownGroups(); }
return this._knownGroups[i];
},
/**
* Initializes bignum objects for known group parameters.
* @private
*/
_didInitKnownGroups: false,
_initKnownGroups:function() {
var i, size, group;
for (i=0; i < this._knownGroupSizes.length; i++) {
size = this._knownGroupSizes[i].toString();
group = this._knownGroups[size];
group.N = new sjcl.bn(group.N);
group.g = new sjcl.bn(group.g);
}
this._didInitKnownGroups = true;
},
_knownGroupSizes: [1024, 1536, 2048],
_knownGroups: {
1024: {
N: "EEAF0AB9ADB38DD69C33F80AFA8FC5E86072618775FF3C0B9EA2314C" +
"9C256576D674DF7496EA81D3383B4813D692C6E0E0D5D8E250B98BE4" +
"8E495C1D6089DAD15DC7D7B46154D6B6CE8EF4AD69B15D4982559B29" +
"7BCF1885C529F566660E57EC68EDBC3C05726CC02FD4CBF4976EAA9A" +
"FD5138FE8376435B9FC61D2FC0EB06E3",
g:2
},
1536: {
N: "9DEF3CAFB939277AB1F12A8617A47BBBDBA51DF499AC4C80BEEEA961" +
"4B19CC4D5F4F5F556E27CBDE51C6A94BE4607A291558903BA0D0F843" +
"80B655BB9A22E8DCDF028A7CEC67F0D08134B1C8B97989149B609E0B" +
"E3BAB63D47548381DBC5B1FC764E3F4B53DD9DA1158BFD3E2B9C8CF5" +
"6EDF019539349627DB2FD53D24B7C48665772E437D6C7F8CE442734A" +
"F7CCB7AE837C264AE3A9BEB87F8A2FE9B8B5292E5A021FFF5E91479E" +
"8CE7A28C2442C6F315180F93499A234DCF76E3FED135F9BB",
g: 2
},
2048: {
N: "AC6BDB41324A9A9BF166DE5E1389582FAF72B6651987EE07FC319294" +
"3DB56050A37329CBB4A099ED8193E0757767A13DD52312AB4B03310D" +
"CD7F48A9DA04FD50E8083969EDB767B0CF6095179A163AB3661A05FB" +
"D5FAAAE82918A9962F0B93B855F97993EC975EEAA80D740ADBF4FF74" +
"7359D041D5C33EA71D281E446B14773BCA97B43A23FB801676BD207A" +
"436C6481F1D2B9078717461A5B9D32E688F87748544523B524B0D57D" +
"5EA77A2775D2ECFA032CFBDBF52FB3786160279004E57AE6AF874E73" +
"03CE53299CCC041C7BC308D82A5698F3A8D0C38271AE35F8E9DBFBB6" +
"94B5C803D89F7AE435DE236D525F54759B65E372FCD68EF20FA7111F" +
"9E4AFF73",
g: 2
}
}
};