1 files changed, 67 insertions, 0 deletions
diff --git a/crypto/src/tls/CombinedHash.cs b/crypto/src/tls/CombinedHash.cs
new file mode 100644
index 000000000..71151d2a5
--- /dev/null
+++ b/crypto/src/tls/CombinedHash.cs
@@ -0,0 +1,67 @@
+using System;
+
+using Org.BouncyCastle.Tls.Crypto;
+using Org.BouncyCastle.Utilities;
+
+namespace Org.BouncyCastle.Tls
+{
+    /// <summary>A combined hash, which implements md5(m) || sha1(m).</summary>
+    public class CombinedHash
+        : TlsHash
+    {
+        protected readonly TlsContext m_context;
+        protected readonly TlsCrypto m_crypto;
+        protected readonly TlsHash m_md5;
+        protected readonly TlsHash m_sha1;
+
+        internal CombinedHash(TlsContext context, TlsHash md5, TlsHash sha1)
+        {
+            this.m_context = context;
+            this.m_crypto = context.Crypto;
+            this.m_md5 = md5;
+            this.m_sha1 = sha1;
+        }
+
+        public CombinedHash(TlsCrypto crypto)
+        {
+            this.m_crypto = crypto;
+            this.m_md5 = crypto.CreateHash(CryptoHashAlgorithm.md5);
+            this.m_sha1 = crypto.CreateHash(CryptoHashAlgorithm.sha1);
+        }
+
+        public CombinedHash(CombinedHash t)
+        {
+            this.m_context = t.m_context;
+            this.m_crypto = t.m_crypto;
+            this.m_md5 = t.m_md5.CloneHash();
+            this.m_sha1 = t.m_sha1.CloneHash();
+        }
+
+        public virtual void Update(byte[] input, int inOff, int len)
+        {
+            m_md5.Update(input, inOff, len);
+            m_sha1.Update(input, inOff, len);
+        }
+
+        public virtual byte[] CalculateHash()
+        {
+            if (null != m_context && TlsUtilities.IsSsl(m_context))
+            {
+                Ssl3Utilities.CompleteCombinedHash(m_context, m_md5, m_sha1);
+            }
+
+            return Arrays.Concatenate(m_md5.CalculateHash(), m_sha1.CalculateHash());
+        }
+
+        public virtual TlsHash CloneHash()
+        {
+            return new CombinedHash(this);
+        }
+
+        public virtual void Reset()
+        {
+            m_md5.Reset();
+            m_sha1.Reset();
+        }
+    }
+}