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Diffstat (limited to 'node_modules/miller-rabin/lib/mr.js')
-rw-r--r-- | node_modules/miller-rabin/lib/mr.js | 115 |
1 files changed, 0 insertions, 115 deletions
diff --git a/node_modules/miller-rabin/lib/mr.js b/node_modules/miller-rabin/lib/mr.js deleted file mode 100644 index 60d2a8e..0000000 --- a/node_modules/miller-rabin/lib/mr.js +++ /dev/null @@ -1,115 +0,0 @@ -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; -}; |