1+ /*
2+ * Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
3+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4+ *
5+ * This code is free software; you can redistribute it and/or modify it
6+ * under the terms of the GNU General Public License version 2 only, as
7+ * published by the Free Software Foundation.
8+ *
9+ * This code is distributed in the hope that it will be useful, but WITHOUT
10+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12+ * version 2 for more details (a copy is included in the LICENSE file that
13+ * accompanied this code).
14+ *
15+ * You should have received a copy of the GNU General Public License version
16+ * 2 along with this work; if not, write to the Free Software Foundation,
17+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18+ *
19+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20+ * or visit www.oracle.com if you need additional information or have any
21+ * questions.
22+ */
23+
24+ /*
25+ * @test
26+ * @bug 8308474
27+ * @summary Test that calling initSign resets RNG
28+ */
29+
30+ import java .security .KeyPairGenerator ;
31+ import java .security .PrivateKey ;
32+ import java .security .SecureRandom ;
33+ import java .security .Signature ;
34+ import java .util .Arrays ;
35+ import java .util .Random ;
36+
37+
38+ public class SecureRandomReset {
39+
40+ public static void main (String [] args ) throws Exception {
41+ KeyPairGenerator g = KeyPairGenerator .getInstance ("DSA" );
42+ PrivateKey sk = g .generateKeyPair ().getPrivate ();
43+ Signature s = Signature .getInstance ("SHA256withDSA" );
44+
45+ // Initialize deterministic RNG and sign
46+ s .initSign (sk , deterministic ());
47+ byte [] sig1 = s .sign ();
48+
49+ // Re-initialize deterministic RNG and sign
50+ s .initSign (sk , deterministic ());
51+ byte [] sig2 = s .sign ();
52+
53+ if (!Arrays .equals (sig1 ,sig2 )) {
54+ System .out .println ("Expected equal signatures" );
55+ throw new RuntimeException ("initSign not properly resetting RNG" );
56+ }
57+ }
58+
59+ static SecureRandom deterministic () {
60+ return new SecureRandom () {
61+ final Random r = new Random (0 );
62+ @ Override
63+ public void nextBytes (byte [] bytes ) {
64+ r .nextBytes (bytes );
65+ }
66+ };
67+ }
68+ }
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