1 files changed, 152 insertions, 0 deletions
diff --git a/core/src/test/java/org/spongycastle/crypto/test/DigestRandomNumberTest.java b/core/src/test/java/org/spongycastle/crypto/test/DigestRandomNumberTest.java
new file mode 100644
index 00000000..b79eadd3
--- /dev/null
+++ b/core/src/test/java/org/spongycastle/crypto/test/DigestRandomNumberTest.java
@@ -0,0 +1,152 @@
+package org.spongycastle.crypto.test;
+
+import org.spongycastle.util.test.SimpleTest;
+import org.spongycastle.util.encoders.Hex;
+import org.spongycastle.util.Arrays;
+import org.spongycastle.crypto.prng.DigestRandomGenerator;
+import org.spongycastle.crypto.digests.SHA1Digest;
+import org.spongycastle.crypto.digests.SHA256Digest;
+import org.spongycastle.crypto.Digest;
+
+public class DigestRandomNumberTest
+    extends SimpleTest
+{
+    private static final byte[] ZERO_SEED = { 0, 0, 0, 0, 0, 0, 0, 0 };
+
+    private static final byte[] TEST_SEED = Hex.decode("81dcfafc885914057876");
+
+    private static final byte[] expected0SHA1 = Hex.decode("95bca677b3d4ff793213c00892d2356ec729ee02");
+    private static final byte[] noCycle0SHA1 = Hex.decode("d57ccd0eb12c3938d59226412bc1268037b6b846");
+    private static final byte[] expected0SHA256 = Hex.decode("587e2dfd597d086e47ddcd343eac983a5c913bef8c6a1a560a5c1bc3a74b0991");
+    private static final byte[] noCycle0SHA256 = Hex.decode("e5776c4483486ba7be081f4e1b9dafbab25c8fae290fd5474c1ceda2c16f9509");
+    private static final byte[] expected100SHA1 = Hex.decode("b9d924092546e0876cafd4937d7364ebf9efa4be");
+    private static final byte[] expected100SHA256 = Hex.decode("fbc4aa54b948b99de104c44563a552899d718bb75d1941cc62a2444b0506abaf");
+    private static final byte[] expectedTestSHA1 = Hex.decode("e9ecef9f5306daf1ac51a89a211a64cb24415649");
+    private static final byte[] expectedTestSHA256 = Hex.decode("bdab3ca831b472a2fa09bd1bade541ef16c96640a91fcec553679a136061de98");
+
+    private static final byte[] sha1Xors = Hex.decode("7edcc1216934f3891b03ffa65821611a3e2b1f79");
+    private static final byte[] sha256Xors = Hex.decode("5ec48189cc0aa71e79c707bc3c33ffd47bbba368a83d6cfebf3cd3969d7f3eed");
+
+    public String getName()
+    {
+        return "DigestRandomNumber";
+    }
+
+    private void doExpectedTest(Digest digest, int seed, byte[] expected)
+    {
+        doExpectedTest(digest, seed, expected, null);
+    }
+    
+    private void doExpectedTest(Digest digest, int seed, byte[] expected, byte[] noCycle)
+    {
+        DigestRandomGenerator rGen = new DigestRandomGenerator(digest);
+        byte[] output = new byte[digest.getDigestSize()];
+
+        rGen.addSeedMaterial(seed);
+
+        for (int i = 0; i != 1024; i++)
+        {
+             rGen.nextBytes(output);
+        }
+
+        if (noCycle != null)
+        {
+            if (Arrays.areEqual(noCycle, output))
+            {
+                fail("seed not being cycled!");
+            }
+        }
+
+        if (!Arrays.areEqual(expected, output))
+        {
+            fail("expected output doesn't match");
+        }
+    }
+
+    private void doExpectedTest(Digest digest, byte[] seed, byte[] expected)
+    {
+        DigestRandomGenerator rGen = new DigestRandomGenerator(digest);
+        byte[] output = new byte[digest.getDigestSize()];
+
+        rGen.addSeedMaterial(seed);
+
+        for (int i = 0; i != 1024; i++)
+        {
+             rGen.nextBytes(output);
+        }
+
+        if (!Arrays.areEqual(expected, output))
+        {
+            fail("expected output doesn't match");
+        }
+    }
+
+    private void doCountTest(Digest digest, byte[] seed, byte[] expectedXors)
+    {
+        DigestRandomGenerator rGen = new DigestRandomGenerator(digest);
+        byte[] output = new byte[digest.getDigestSize()];
+        int[] averages = new int[digest.getDigestSize()];
+        byte[] ands = new byte[digest.getDigestSize()];
+        byte[] xors = new byte[digest.getDigestSize()];
+        byte[] ors = new byte[digest.getDigestSize()];
+
+        rGen.addSeedMaterial(seed);
+
+        for (int i = 0; i != 1000000; i++)
+        {
+             rGen.nextBytes(output);
+             for (int j = 0; j != output.length; j++)
+             {
+                 averages[j] += output[j] & 0xff;
+                 ands[j] &= output[j];
+                 xors[j] ^= output[j];
+                 ors[j] |= output[j];
+             }
+        }
+               
+        for (int i = 0; i != output.length; i++)
+        {
+            if ((averages[i] / 1000000) != 127)
+            {
+                fail("average test failed for " + digest.getAlgorithmName());
+            }
+            if (ands[i] != 0)
+            {
+                fail("and test failed for " + digest.getAlgorithmName());
+            }
+            if ((ors[i] & 0xff) != 0xff)
+            {
+                fail("or test failed for " + digest.getAlgorithmName());
+            }
+            if (xors[i] != expectedXors[i])
+            {
+                fail("xor test failed for " + digest.getAlgorithmName());
+            }
+        }
+    }
+
+    public void performTest()
+        throws Exception
+    {
+        doExpectedTest(new SHA1Digest(), 0, expected0SHA1, noCycle0SHA1);
+        doExpectedTest(new SHA256Digest(), 0, expected0SHA256, noCycle0SHA256);
+
+        doExpectedTest(new SHA1Digest(), 100, expected100SHA1);
+        doExpectedTest(new SHA256Digest(), 100, expected100SHA256);
+
+        doExpectedTest(new SHA1Digest(), ZERO_SEED, expected0SHA1);
+        doExpectedTest(new SHA256Digest(), ZERO_SEED, expected0SHA256);
+
+        doExpectedTest(new SHA1Digest(), TEST_SEED, expectedTestSHA1);
+        doExpectedTest(new SHA256Digest(), TEST_SEED, expectedTestSHA256);
+
+        doCountTest(new SHA1Digest(), TEST_SEED, sha1Xors);
+        doCountTest(new SHA256Digest(), TEST_SEED, sha256Xors);
+    }
+
+    public static void main(
+        String[]    args)
+    {
+        runTest(new DigestRandomNumberTest());
+    }
+}