1 files changed, 152 insertions, 0 deletions
diff --git a/libraries/spongycastle/core/src/test/java/org/spongycastle/crypto/test/HashCommitmentTest.java b/libraries/spongycastle/core/src/test/java/org/spongycastle/crypto/test/HashCommitmentTest.java
new file mode 100644
index 000000000..d4c1c0768
--- /dev/null
+++ b/libraries/spongycastle/core/src/test/java/org/spongycastle/crypto/test/HashCommitmentTest.java
@@ -0,0 +1,152 @@
+package org.spongycastle.crypto.test;
+
+import java.security.SecureRandom;
+
+import org.spongycastle.crypto.Commitment;
+import org.spongycastle.crypto.Committer;
+import org.spongycastle.crypto.DataLengthException;
+import org.spongycastle.crypto.commitments.GeneralHashCommitter;
+import org.spongycastle.crypto.commitments.HashCommitter;
+import org.spongycastle.crypto.digests.SHA1Digest;
+import org.spongycastle.crypto.digests.SHA256Digest;
+import org.spongycastle.util.Arrays;
+import org.spongycastle.util.encoders.Hex;
+import org.spongycastle.util.test.SimpleTest;
+
+public class HashCommitmentTest
+    extends SimpleTest
+{
+    public String getName()
+    {
+        return "HashCommitmentTest";
+    }
+
+    public void performBasicTest()
+        throws Exception
+    {
+        byte[] data = Hex.decode("4e6f77206973207468652074696d6520666f7220616c6c20");
+
+        Committer committer = new HashCommitter(new SHA256Digest(), new SecureRandom());
+
+        Commitment c = committer.commit(data);
+
+        committer = new HashCommitter(new SHA256Digest(), new SecureRandom());
+
+        if (!committer.isRevealed(c, data))
+        {
+            fail("commitment failed to validate");
+        }
+
+        committer = new HashCommitter(new SHA1Digest(), new SecureRandom());
+
+        if (committer.isRevealed(c, data))
+        {
+            fail("commitment validated!!");
+        }
+
+        try
+        {
+            committer.isRevealed(c, new byte[data.length + 1]);
+        }
+        catch (Exception e)
+        {
+            if (!e.getMessage().equals("Message and witness secret lengths do not match."))
+            {
+                fail("exception thrown but wrong message");
+            }
+        }
+
+        // SHA1 has a block size of 512 bits, try a message that's too big
+
+        try
+        {
+            c = committer.commit(new byte[33]);
+        }
+        catch (DataLengthException e)
+        {
+            if (!e.getMessage().equals("Message to be committed to too large for digest."))
+            {
+                fail("exception thrown but wrong message");
+            }
+        }
+    }
+
+    public void performGeneralTest()
+        throws Exception
+    {
+        byte[] data = Hex.decode("4e6f77206973207468652074696d6520666f7220616c6c20");
+
+        Committer committer = new GeneralHashCommitter(new SHA256Digest(), new SecureRandom());
+
+        Commitment c = committer.commit(data);
+
+        committer = new GeneralHashCommitter(new SHA256Digest(), new SecureRandom());
+
+        if (!committer.isRevealed(c, data))
+        {
+            fail("general commitment failed to validate");
+        }
+
+        committer = new GeneralHashCommitter(new SHA1Digest(), new SecureRandom());
+
+        if (committer.isRevealed(c, data))
+        {
+            fail("general commitment validated!!");
+        }
+
+        c = committer.commit(data);
+
+        // try and fool it.
+        byte[] s = c.getSecret();
+        byte[] newS = Arrays.copyOfRange(s, 0, s.length - 1);
+        byte[] newData = new byte[data.length + 1];
+
+        newData[0] = s[s.length - 1];
+        System.arraycopy(data, 0, newData, 1, data.length);
+
+        c = new Commitment(newS, c.getCommitment());
+
+        if (committer.isRevealed(c, newData))
+        {
+            fail("general commitment validated!!");
+        }
+
+        try
+        {
+            committer.isRevealed(c, new byte[data.length + 1]);
+        }
+        catch (Exception e)
+        {
+            if (!e.getMessage().equals("Message and witness secret lengths do not match."))
+            {
+                fail("exception thrown but wrong message");
+            }
+        }
+
+        // SHA1 has a block size of 512 bits, try a message that's too big
+
+        try
+        {
+            c = committer.commit(new byte[33]);
+        }
+        catch (DataLengthException e)
+        {
+            if (!e.getMessage().equals("Message to be committed to too large for digest."))
+            {
+                fail("exception thrown but wrong message");
+            }
+        }
+    }
+
+    public void performTest()
+        throws Exception
+    {
+        performBasicTest();
+        performGeneralTest();
+    }
+
+    public static void main(String[] args)
+    {
+        runTest(new HashCommitmentTest());
+    }
+}