--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.crypto.ec/share/classes/sun/security/ec/XDHKeyPairGenerator.java	Tue May 08 09:47:28 2018 -0400
@@ -0,0 +1,132 @@
+/*
+ * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package sun.security.ec;
+
+import java.math.BigInteger;
+import java.security.KeyPairGeneratorSpi;
+import java.security.InvalidKeyException;
+import java.security.InvalidParameterException;
+import java.security.InvalidAlgorithmParameterException;
+import java.security.KeyPair;
+import java.security.ProviderException;
+import java.security.SecureRandom;
+import java.security.spec.AlgorithmParameterSpec;
+import java.security.spec.NamedParameterSpec;
+
+import sun.security.jca.JCAUtil;
+
+/**
+ * Key pair generator for the XDH key agreement algorithm.
+ */
+public class XDHKeyPairGenerator extends KeyPairGeneratorSpi {
+
+    private static final NamedParameterSpec DEFAULT_PARAM_SPEC
+        = NamedParameterSpec.X25519;
+
+    private SecureRandom random = null;
+    private XECOperations ops = null;
+    private XECParameters lockedParams = null;
+
+    XDHKeyPairGenerator() {
+        tryInitialize(DEFAULT_PARAM_SPEC);
+    }
+
+    private XDHKeyPairGenerator(NamedParameterSpec paramSpec) {
+        tryInitialize(paramSpec);
+        lockedParams = ops.getParameters();
+    }
+
+    private void tryInitialize(NamedParameterSpec paramSpec) {
+        try {
+            initialize(paramSpec, null);
+        } catch (InvalidAlgorithmParameterException ex) {
+            String name = paramSpec.getName();
+            throw new ProviderException(name + " not supported");
+        }
+    }
+
+    @Override
+    public void initialize(int keySize, SecureRandom random) {
+
+        XECParameters params = XECParameters.getBySize(
+            InvalidParameterException::new, keySize);
+
+        initializeImpl(params, random);
+    }
+
+    @Override
+    public void initialize(AlgorithmParameterSpec params, SecureRandom random)
+            throws InvalidAlgorithmParameterException {
+
+        XECParameters xecParams = XECParameters.get(
+            InvalidAlgorithmParameterException::new, params);
+
+        initializeImpl(xecParams, random);
+    }
+
+    private void initializeImpl(XECParameters params, SecureRandom random) {
+
+        if (lockedParams != null && lockedParams != params) {
+            throw new InvalidParameterException("Parameters must be " +
+                lockedParams.getName());
+        }
+
+        this.ops = new XECOperations(params);
+        this.random = random == null ? JCAUtil.getSecureRandom() : random;
+    }
+
+
+    @Override
+    public KeyPair generateKeyPair() {
+
+        byte[] privateKey = ops.generatePrivate(random);
+        // computePublic may modify the private key, so clone it first
+        BigInteger publicKey = ops.computePublic(privateKey.clone());
+
+        try {
+            return new KeyPair(
+                new XDHPublicKeyImpl(ops.getParameters(), publicKey),
+                new XDHPrivateKeyImpl(ops.getParameters(), privateKey)
+            );
+        } catch (InvalidKeyException ex) {
+            throw new ProviderException(ex);
+        }
+    }
+
+    static class X25519 extends XDHKeyPairGenerator {
+
+        public X25519() {
+            super(NamedParameterSpec.X25519);
+        }
+    }
+
+    static class X448 extends XDHKeyPairGenerator {
+
+        public X448() {
+            super(NamedParameterSpec.X448);
+        }
+    }
+}