1 files changed, 164 insertions, 0 deletions
diff --git a/node_modules/diffie-hellman/lib/dh.js b/node_modules/diffie-hellman/lib/dh.js
new file mode 100644
index 0000000..0650f65
--- /dev/null
+++ b/node_modules/diffie-hellman/lib/dh.js
@@ -0,0 +1,164 @@
+var BN = require('bn.js');
+var MillerRabin = require('miller-rabin');
+var millerRabin = new MillerRabin();
+var TWENTYFOUR = new BN(24);
+var ELEVEN = new BN(11);
+var TEN = new BN(10);
+var THREE = new BN(3);
+var SEVEN = new BN(7);
+var primes = require('./generatePrime');
+var randomBytes = require('randombytes');
+module.exports = DH;
+
+function setPublicKey(pub, enc) {
+  enc = enc || 'utf8';
+  if (!Buffer.isBuffer(pub)) {
+    pub = new Buffer(pub, enc);
+  }
+  this._pub = new BN(pub);
+  return this;
+}
+
+function setPrivateKey(priv, enc) {
+  enc = enc || 'utf8';
+  if (!Buffer.isBuffer(priv)) {
+    priv = new Buffer(priv, enc);
+  }
+  this._priv = new BN(priv);
+  return this;
+}
+
+var primeCache = {};
+function checkPrime(prime, generator) {
+  var gen = generator.toString('hex');
+  var hex = [gen, prime.toString(16)].join('_');
+  if (hex in primeCache) {
+    return primeCache[hex];
+  }
+  var error = 0;
+
+  if (prime.isEven() ||
+    !primes.simpleSieve ||
+    !primes.fermatTest(prime) ||
+    !millerRabin.test(prime)) {
+    //not a prime so +1
+    error += 1;
+
+    if (gen === '02' || gen === '05') {
+      // we'd be able to check the generator
+      // it would fail so +8
+      error += 8;
+    } else {
+      //we wouldn't be able to test the generator
+      // so +4
+      error += 4;
+    }
+    primeCache[hex] = error;
+    return error;
+  }
+  if (!millerRabin.test(prime.shrn(1))) {
+    //not a safe prime
+    error += 2;
+  }
+  var rem;
+  switch (gen) {
+    case '02':
+      if (prime.mod(TWENTYFOUR).cmp(ELEVEN)) {
+        // unsuidable generator
+        error += 8;
+      }
+      break;
+    case '05':
+      rem = prime.mod(TEN);
+      if (rem.cmp(THREE) && rem.cmp(SEVEN)) {
+        // prime mod 10 needs to equal 3 or 7
+        error += 8;
+      }
+      break;
+    default:
+      error += 4;
+  }
+  primeCache[hex] = error;
+  return error;
+}
+
+function DH(prime, generator, malleable) {
+  this.setGenerator(generator);
+  this.__prime = new BN(prime);
+  this._prime = BN.mont(this.__prime);
+  this._primeLen = prime.length;
+  this._pub = undefined;
+  this._priv = undefined;
+  this._primeCode = undefined;
+  if (malleable) {
+    this.setPublicKey = setPublicKey;
+    this.setPrivateKey = setPrivateKey;
+  } else {
+    this._primeCode = 8;
+  }
+}
+Object.defineProperty(DH.prototype, 'verifyError', {
+  enumerable: true,
+  get: function () {
+    if (typeof this._primeCode !== 'number') {
+      this._primeCode = checkPrime(this.__prime, this.__gen);
+    }
+    return this._primeCode;
+  }
+});
+DH.prototype.generateKeys = function () {
+  if (!this._priv) {
+    this._priv = new BN(randomBytes(this._primeLen));
+  }
+  this._pub = this._gen.toRed(this._prime).redPow(this._priv).fromRed();
+  return this.getPublicKey();
+};
+
+DH.prototype.computeSecret = function (other) {
+  other = new BN(other);
+  other = other.toRed(this._prime);
+  var secret = other.redPow(this._priv).fromRed();
+  var out = new Buffer(secret.toArray());
+  var prime = this.getPrime();
+  if (out.length < prime.length) {
+    var front = new Buffer(prime.length - out.length);
+    front.fill(0);
+    out = Buffer.concat([front, out]);
+  }
+  return out;
+};
+
+DH.prototype.getPublicKey = function getPublicKey(enc) {
+  return formatReturnValue(this._pub, enc);
+};
+
+DH.prototype.getPrivateKey = function getPrivateKey(enc) {
+  return formatReturnValue(this._priv, enc);
+};
+
+DH.prototype.getPrime = function (enc) {
+  return formatReturnValue(this.__prime, enc);
+};
+
+DH.prototype.getGenerator = function (enc) {
+  return formatReturnValue(this._gen, enc);
+};
+
+DH.prototype.setGenerator = function (gen, enc) {
+  enc = enc || 'utf8';
+  if (!Buffer.isBuffer(gen)) {
+    gen = new Buffer(gen, enc);
+  }
+  this.__gen = gen;
+  this._gen = new BN(gen);
+  return this;
+};
+
+function formatReturnValue(bn, enc) {
+  var buf = new Buffer(bn.toArray());
+  if (!enc) {
+    return buf;
+  } else {
+    return buf.toString(enc);
+  }
+}