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-rw-r--r--node_modules/miller-rabin/lib/mr.js115
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diff --git a/node_modules/miller-rabin/lib/mr.js b/node_modules/miller-rabin/lib/mr.js
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+var bn = require('bn.js');
+var brorand = require('brorand');
+
+function MillerRabin(rand) {
+ this.rand = rand || new brorand.Rand();
+}
+module.exports = MillerRabin;
+
+MillerRabin.create = function create(rand) {
+ return new MillerRabin(rand);
+};
+
+MillerRabin.prototype._randbelow = function _randbelow(n) {
+ var len = n.bitLength();
+ var min_bytes = Math.ceil(len / 8);
+
+ // Generage random bytes until a number less than n is found.
+ // This ensures that 0..n-1 have an equal probability of being selected.
+ do
+ var a = new bn(this.rand.generate(min_bytes));
+ while (a.cmp(n) >= 0);
+
+ return a;
+};
+
+MillerRabin.prototype._randrange = function _randrange(start, stop) {
+ // Generate a random number greater than or equal to start and less than stop.
+ var size = stop.sub(start);
+ return start.add(this._randbelow(size));
+};
+
+MillerRabin.prototype.test = function test(n, k, cb) {
+ var len = n.bitLength();
+ var red = bn.mont(n);
+ var rone = new bn(1).toRed(red);
+
+ if (!k)
+ k = Math.max(1, (len / 48) | 0);
+
+ // Find d and s, (n - 1) = (2 ^ s) * d;
+ var n1 = n.subn(1);
+ for (var s = 0; !n1.testn(s); s++) {}
+ var d = n.shrn(s);
+
+ var rn1 = n1.toRed(red);
+
+ var prime = true;
+ for (; k > 0; k--) {
+ var a = this._randrange(new bn(2), n1);
+ if (cb)
+ cb(a);
+
+ var x = a.toRed(red).redPow(d);
+ if (x.cmp(rone) === 0 || x.cmp(rn1) === 0)
+ continue;
+
+ for (var i = 1; i < s; i++) {
+ x = x.redSqr();
+
+ if (x.cmp(rone) === 0)
+ return false;
+ if (x.cmp(rn1) === 0)
+ break;
+ }
+
+ if (i === s)
+ return false;
+ }
+
+ return prime;
+};
+
+MillerRabin.prototype.getDivisor = function getDivisor(n, k) {
+ var len = n.bitLength();
+ var red = bn.mont(n);
+ var rone = new bn(1).toRed(red);
+
+ if (!k)
+ k = Math.max(1, (len / 48) | 0);
+
+ // Find d and s, (n - 1) = (2 ^ s) * d;
+ var n1 = n.subn(1);
+ for (var s = 0; !n1.testn(s); s++) {}
+ var d = n.shrn(s);
+
+ var rn1 = n1.toRed(red);
+
+ for (; k > 0; k--) {
+ var a = this._randrange(new bn(2), n1);
+
+ var g = n.gcd(a);
+ if (g.cmpn(1) !== 0)
+ return g;
+
+ var x = a.toRed(red).redPow(d);
+ if (x.cmp(rone) === 0 || x.cmp(rn1) === 0)
+ continue;
+
+ for (var i = 1; i < s; i++) {
+ x = x.redSqr();
+
+ if (x.cmp(rone) === 0)
+ return x.fromRed().subn(1).gcd(n);
+ if (x.cmp(rn1) === 0)
+ break;
+ }
+
+ if (i === s) {
+ x = x.redSqr();
+ return x.fromRed().subn(1).gcd(n);
+ }
+ }
+
+ return false;
+};