8300399: EdDSA does not verify when there is no message

Reviewed-by: ascarpino

src/jdk.crypto.ec/share/classes/sun/security/ec/ed/EdDSASignature.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2020, 2023, 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
@@ -210,9 +210,7 @@ protected boolean engineVerify(byte[] sigBytes) throws SignatureException {
         if (publicKeyBytes == null) {
             throw new SignatureException("Missing publicKey");
         }
-        if (message == null) {
-            return false;
-        }
+        ensureMessageInit();
         boolean result = ops.verify(this.sigParams, this.publicKeyPoint,
             this.publicKeyBytes, message.getMessage(), sigBytes);
         message = null;

test/jdk/sun/security/ec/ed/EmptyMessage.java

@@ -0,0 +1,50 @@
+/*
+ * Copyright (c) 2023, 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.
+ *
+ * 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.
+ */
+
+/*
+ * @test
+ * @bug 8300399
+ * @summary EdDSA does not verify when there is no message
+ * @run main EmptyMessage
+ */
+import java.security.KeyPairGenerator;
+import java.security.Signature;
+import java.security.spec.NamedParameterSpec;
+
+public class EmptyMessage {
+    public static void main(String[] args) throws Exception {
+        var g = KeyPairGenerator.getInstance("EdDSA");
+        g.initialize(NamedParameterSpec.ED25519);
+        var kp = g.generateKeyPair();
+
+        var ss = Signature.getInstance("EdDSA");
+        ss.initSign(kp.getPrivate());
+        var sig = ss.sign();
+
+        var ps = Signature.getInstance("EdDSA");
+        ps.initVerify(kp.getPublic());
+        if (!ps.verify(sig)) {
+            throw new RuntimeException();
+        }
+    }
+}