Sha256: 6425a097b26b8fd083d1a525e66e4cdc12e3393be1c86e4727d1d5863b38edab
Contents?: true
Size: 1.18 KB
Versions: 39
Compression:
Stored size: 1.18 KB
Contents
var bn = require('bn.js');
var randomBytes = require('randombytes');
module.exports = crt;
function blind(priv) {
var r = getr(priv);
var blinder = r.toRed(bn.mont(priv.modulus))
.redPow(new bn(priv.publicExponent)).fromRed();
return {
blinder: blinder,
unblinder:r.invm(priv.modulus)
};
}
function crt(msg, priv) {
var blinds = blind(priv);
var len = priv.modulus.byteLength();
var mod = bn.mont(priv.modulus);
var blinded = new bn(msg).mul(blinds.blinder).umod(priv.modulus);
var c1 = blinded.toRed(bn.mont(priv.prime1));
var c2 = blinded.toRed(bn.mont(priv.prime2));
var qinv = priv.coefficient;
var p = priv.prime1;
var q = priv.prime2;
var m1 = c1.redPow(priv.exponent1);
var m2 = c2.redPow(priv.exponent2);
m1 = m1.fromRed();
m2 = m2.fromRed();
var h = m1.isub(m2).imul(qinv).umod(p);
h.imul(q);
m2.iadd(h);
return new Buffer(m2.imul(blinds.unblinder).umod(priv.modulus).toArray(false, len));
}
crt.getr = getr;
function getr(priv) {
var len = priv.modulus.byteLength();
var r = new bn(randomBytes(len));
while (r.cmp(priv.modulus) >= 0 || !r.umod(priv.prime1) || !r.umod(priv.prime2)) {
r = new bn(randomBytes(len));
}
return r;
}
Version data entries
39 entries across 39 versions & 13 rubygems