8166597: Crypto support for the EdDSA Signature Algorithm

Reviewed-by: weijun, mullan, wetmore

src/java.base/share/classes/java/security/spec/EdECPoint.java

@@ -0,0 +1,86 @@
+/*
+ * Copyright (c) 2020, 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 java.security.spec;
+
+import java.math.BigInteger;
+import java.util.Objects;
+
+/**
+ * An elliptic curve point used to specify keys as defined by
+ * <a href="https://tools.ietf.org/html/rfc8032">RFC 8032: Edwards-Curve
+ * Digital Signature Algorithm (EdDSA)</a>. These points are distinct from the
+ * points represented by {@code ECPoint}, and they are intended for use with
+ * algorithms based on RFC 8032 such as the EdDSA {@code Signature} algorithm.
+ * <p>
+ * An EdEC point is specified by its y-coordinate value and a boolean that
+ * indicates whether the x-coordinate is odd. The y-coordinate is an
+ * element of the field of integers modulo some value p that is determined by
+ * the algorithm parameters. This field element is represented by a
+ * {@code BigInteger}, and implementations that consume objects of this class
+ * may reject integer values which are not in the range [0, p).
+ *
+ * @since 15
+ */
+
+public final class EdECPoint {
+
+    private final boolean xOdd;
+    private final BigInteger y;
+
+    /**
+     * Construct an EdECPoint.
+     *
+     * @param xOdd whether the x-coordinate is odd.
+     * @param y the y-coordinate, represented using a {@code BigInteger}.
+     *
+     * @throws NullPointerException if {@code y} is null.
+     */
+    public EdECPoint(boolean xOdd, BigInteger y) {
+
+        Objects.requireNonNull(y, "y must not be null");
+
+        this.xOdd = xOdd;
+        this.y = y;
+    }
+
+    /**
+     * Get whether the x-coordinate of the point is odd.
+     *
+     * @return a boolean indicating whether the x-coordinate is odd.
+     */
+    public boolean isXOdd() {
+        return xOdd;
+    }
+
+    /**
+     * Get the y-coordinate of the point.
+     *
+     * @return the y-coordinate, represented using a {@code BigInteger}.
+     */
+    public BigInteger getY() {
+        return y;
+    }
+}