--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/rtp/srtpstack/inc/msrtpauthentication.h	Tue Feb 02 01:03:15 2010 +0200
@@ -0,0 +1,49 @@
+/*
+* Copyright (c) 2004 Nokia Corporation and/or its subsidiary(-ies).
+* All rights reserved.
+* This component and the accompanying materials are made available
+* under the terms of "Eclipse Public License v1.0"
+* which accompanies this distribution, and is available
+* at the URL "http://www.eclipse.org/legal/epl-v10.html".
+*
+* Initial Contributors:
+* Nokia Corporation - initial contribution.
+*
+* Contributors:
+*
+* Description:    Provides an abstract class for authentication (integrity protection)
+*
+*/
+
+
+
+
+#ifndef __MSRTP_AUTHENTICATION_H__
+#define __MSRTP_AUTHENTICATION_H__
+
+#include <e32base.h>
+
+class MSRTPAuthentication
+    {
+    public:
+        /**
+        * This function is called by SRTP for authentication/integrity protection
+        * to create authentication tag regardless of the algorithm, 
+        * the default algorith is HMAC-SHA1.
+        * Produces authentication tag based on input key and data M.
+        * result IS truncated to n_tag leftmost bits
+        * @param aBitLength  authentication tag length, 32 or 80 bits
+        * @param aKey  authentication key (n_a)
+        * @param aAuthPortion data to be integrity protected 
+        * @param aRoc packet ROC 
+	    * Returns HBufC8* authentication tag (untruncated) 
+        */
+        virtual HBufC8* AuthenticateL(TUint aBitLength,
+                                    const TDesC8& aKey, 
+                                    const TDesC8& aAuthPortion,
+                                    const TDesC8& aRoc) = 0;
+
+        virtual ~MSRTPAuthentication() { };                                
+    };
+
+#endif // __MSRTP_AUTHENTICATION_H__