Extend EncodableDigest implementation to all SHA-2 digests.

1 files changed, 22 insertions, 0 deletions

diff --git a/core/src/main/java/org/bouncycastle/crypto/digests/SHA512tDigest.java b/core/src/main/java/org/bouncycastle/crypto/digests/SHA512tDigest.java
index 46154618..9abf73b4 100644
--- a/core/src/main/java/org/bouncycastle/crypto/digests/SHA512tDigest.java
+++ b/core/src/main/java/org/bouncycastle/crypto/digests/SHA512tDigest.java
@@ -2,6 +2,7 @@ package org.bouncycastle.crypto.digests;
 
 import org.bouncycastle.util.Memoable;
 import org.bouncycastle.util.MemoableResetException;
+import org.bouncycastle.util.Pack;
 
 /**
  * FIPS 180-4 implementation of SHA-512/t
@@ -53,6 +54,17 @@ public class SHA512tDigest
         reset(t);
     }
 
+    public SHA512tDigest(byte[] encodedState)
+    {
+        this(readDigestLength(encodedState));
+        restoreState(encodedState);
+    }
+
+    private static int readDigestLength(byte[] encodedState)
+    {
+        return Pack.bigEndianToInt(encodedState, encodedState.length - 4);
+    }
+
     public String getAlgorithmName()
     {
         return "SHA-512/" + Integer.toString(digestLength * 8);
@@ -202,4 +214,14 @@ public class SHA512tDigest
         this.H7t = t.H7t;
         this.H8t = t.H8t;
     }
+
+    public byte[] getEncodedState()
+    {
+        final int baseSize = getEncodedStateSize();
+        byte[] encoded = new byte[baseSize + 4];
+        populateState(encoded);
+        Pack.intToBigEndian(digestLength * 8, encoded, baseSize);
+        return encoded;
+    }
+
 }