diff --git a/jni/libzrtp/src/libzrtpcpp/ZrtpCallback.h b/jni/libzrtp/src/libzrtpcpp/ZrtpCallback.h
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+/*
+  Copyright (C) 2006-2010 Werner Dittmann
+
+  This program is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef _ZRTPCALLBACK_H_
+#define _ZRTPCALLBACK_H_
+
+/**
+ * @file ZrtpCallback.h
+ * @brief Callback interface between ZRTP and the RTP stack implementation
+ * @ingroup GNU_ZRTP
+ * @{
+ */
+
+#include <string>
+#include <stdint.h>
+#include <libzrtpcpp/ZrtpCodes.h>
+
+#ifndef __EXPORT
+  #if __GNUC__ >= 4
+    #define __EXPORT    __attribute__ ((visibility("default")))
+    #define __LOCAL     __attribute__ ((visibility("hidden")))
+  #elif defined _WIN32 || defined __CYGWIN__
+    #define __EXPORT    __declspec(dllimport)
+    #define __LOCAL
+  #else
+    #define __EXPORT
+    #define __LOCAL
+  #endif
+#endif
+
+/**
+ * This enum defines which role a ZRTP peer has.
+ *
+ * According to the ZRTP specification the role determines which keys to
+ * use to encrypt or decrypt SRTP data.
+ *
+ * <ul>
+ * <li> The Initiator encrypts SRTP data using the <em>keyInitiator</em> and the
+ *      <em>saltInitiator</em> data, the Responder uses these data to decrypt.
+ * </li>
+ * <li> The Responder encrypts SRTP data using the <em>keyResponder</em> and the
+ *      <em>saltResponder</em> data, the Initiator uses these data to decrypt.
+ * </li>
+ * </ul>
+ */
+typedef enum  {
+    Responder = 1,  ///< This client is in ZRTP Responder mode
+    Initiator       ///< This client is in ZRTP Initiator mode
+} Role;
+
+/// The algorihms that we support in SRTP and that ZRTP can negotiate.
+typedef enum {
+    None,
+    Aes = 1,        ///< Use AES as symmetrical cipher algorithm
+    TwoFish,        ///< Use TwoFish as symmetrical cipher algorithm
+    Sha1,           ///< Use Sha1 as authentication algorithm
+    Skein           ///< Use Skein as authentication algorithm
+} SrtpAlgorithms;
+
+/**
+ * This structure contains pointers to the SRTP secrets and the role info.
+ *
+ * About the role and what the meaning of the role is refer to the
+ * of the enum Role. The pointers to the secrets are valid as long as
+ * the ZRtp object is active. To use these data after the ZRtp object's
+ * lifetime you may copy the data into a save place. The destructor
+ * of ZRtp clears the data.
+ */
+typedef struct srtpSecrets {
+    SrtpAlgorithms symEncAlgorithm;     ///< symmetrical cipher algorithm
+    const uint8_t* keyInitiator;        ///< Initiator's key
+    int32_t initKeyLen;                 ///< Initiator's key length
+    const uint8_t* saltInitiator;       ///< Initiator's salt
+    int32_t initSaltLen;                ///< Initiator's salt length
+    const uint8_t* keyResponder;        ///< Responder's key
+    int32_t respKeyLen;                 ///< Responder's key length
+    const uint8_t* saltResponder;       ///< Responder's salt
+    int32_t respSaltLen;                ///< Responder's salt length
+    SrtpAlgorithms authAlgorithm;       ///< SRTP authentication algorithm
+    int32_t srtpAuthTagLen;             ///< SRTP authentication length
+    std::string sas;                    ///< The SAS string
+    Role  role;                         ///< ZRTP role of this client
+} SrtpSecret_t;
+
+enum EnableSecurity {
+    ForReceiver = 1,        ///< Enable security for SRTP receiver
+    ForSender   = 2         ///< Enable security for SRTP sender
+};
+
+/**
+ * This abstract class defines the callback functions required by GNU ZRTP.
+ *
+ * This class is a pure abstract class, aka Interface in Java, that
+ * defines the callback interface that the specific part of a GNU ZRTP
+ * must implement. The generic part of GNU ZRTP uses these mehtods
+ * to communicate with the specific part, for example to send data
+ * via the RTP/SRTP stack, to set timers and cancel timer and so on.
+ *
+ * The generiy part of GNU ZRTP needs only a few callback methods to
+ * be implemented by the specific part.
+ *
+ * @author Werner Dittmann <Werner.Dittmann@t-online.de>
+ */
+
+class __EXPORT ZrtpCallback {
+
+protected:
+    friend class ZRtp;
+
+    virtual ~ZrtpCallback() {};
+
+    /**
+     * Send a ZRTP packet via RTP.
+     *
+     * ZRTP calls this method to send a ZRTP packet via the RTP session.
+     *
+     * @param data
+     *    Points to ZRTP packet to send.
+     * @param length
+     *    The length in bytes of the data
+     * @return
+     *    zero if sending failed, one if packet was send
+     */
+    virtual int32_t sendDataZRTP(const uint8_t* data, int32_t length) =0;
+
+    /**
+     * Activate timer.
+     *
+     * @param time
+     *    The time in ms for the timer
+     * @return
+     *    zero if activation failed, one if timer was activated
+     */
+    virtual int32_t activateTimer(int32_t time) =0;
+
+    /**
+     * Cancel the active timer.
+     *
+     * @return
+     *    zero if cancel action failed, one if timer was canceled
+     */
+    virtual int32_t cancelTimer() =0;
+
+    /**
+     * Send information messages to the hosting environment.
+     *
+     * The ZRTP implementation uses this method to send information
+     * messages to the host. Along with the message ZRTP provides a
+     * severity indicator that defines: Info, Warning, Error,
+     * Alert. Refer to the <code>MessageSeverity</code> enum above.
+     *
+     * @param severity
+     *     This defines the message's severity
+     * @param subCode
+     *     The subcode identifying the reason.
+     * @see ZrtpCodes#MessageSeverity
+     */
+    virtual void sendInfo(GnuZrtpCodes::MessageSeverity severity, int32_t subCode) =0;
+
+    /**
+     * SRTP crypto data ready for the sender or receiver.
+     *
+     * The ZRTP implementation calls this method right after all SRTP
+     * secrets are computed and ready to be used. The parameter points
+     * to a structure that contains pointers to the SRTP secrets and a
+     * <code>enum Role</code>. The called method (the implementation
+     * of this abstract method) must either copy the pointers to the SRTP
+     * data or the SRTP data itself to a save place. The SrtpSecret_t
+     * structure is destroyed after the callback method returns to the
+     * ZRTP implementation.
+     *
+     * The SRTP data themselfs are ontained in the ZRtp object and are
+     * valid as long as the ZRtp object is active. TheZRtp's
+     * destructor clears the secrets. Thus the called method needs to
+     * save the pointers only, ZRtp takes care of the data.
+     *
+     * The implementing class may enable SRTP processing in this
+     * method or delay it to srtpSecertsOn().
+     *
+     * @param secrets A pointer to a SrtpSecret_t structure that
+     *     contains all necessary data.
+     *
+     * @param part for which part (Sender or Receiver) this data is
+     *     valid.
+     *
+     * @return Returns false if something went wrong during
+     *    initialization of SRTP context, for example memory shortage.
+     */
+    virtual bool srtpSecretsReady(SrtpSecret_t* secrets, EnableSecurity part) =0;
+
+    /**
+     * Switch off the security for the defined part.
+     *
+     * @param part Defines for which part (sender or receiver) to
+     *    switch on security
+     */
+    virtual void srtpSecretsOff(EnableSecurity part) =0;
+
+    /**
+     * Switch on the security.
+     *
+     * ZRTP calls this method after it has computed the SAS and check
+     * if it is verified or not. In addition ZRTP provides information
+     * about the cipher algorithm and key length for the SRTP session.
+     *
+     * This method must enable SRTP processing if it was not enabled
+     * during sertSecretsReady().
+     *
+     * @param c The name of the used cipher algorithm and mode, or
+     *    NULL
+     *
+     * @param s The SAS string
+     *
+     * @param verified if <code>verified</code> is true then SAS was
+     *    verified by both parties during a previous call.
+     */
+    virtual void srtpSecretsOn(std::string c, std::string s, bool verified) =0;
+
+    /**
+     * This method handles GoClear requests.
+     *
+     * According to the ZRTP specification the user must be informed about
+     * a GoClear request because the ZRTP implementation switches off security
+     * if it could authenticate the GoClear packet.
+     *
+     * <b>Note:</b> GoClear is not yet implemented in GNU ZRTP.
+     *
+     */
+    virtual void handleGoClear() =0;
+
+    /**
+     * Handle ZRTP negotiation failed.
+     *
+     * ZRTP calls this method in case ZRTP negotiation failed. The
+     * parameters show the severity as well as the reason.
+     *
+     * @param severity
+     *     This defines the message's severity
+     * @param subCode
+     *     The subcode identifying the reason.
+     * @see ZrtpCodes#MessageSeverity
+     */
+    virtual void zrtpNegotiationFailed(GnuZrtpCodes::MessageSeverity severity, int32_t subCode) =0;
+
+    /**
+     * ZRTP calls this method if the other side does not support ZRTP.
+     *
+     * If the other side does not answer the ZRTP <em>Hello</em> packets then
+     * ZRTP calls this method,
+     *
+     */
+    virtual void zrtpNotSuppOther() =0;
+
+    /**
+     * Enter synchronization mutex.
+     *
+     * GNU ZRTP requires one mutes to synchronize its
+     * processing. Because mutex implementations depend on the
+     * underlying infrastructure, for example operating system or
+     * thread implementation, GNU ZRTP delegates mutex handling to the
+     * spcific part of its implementation.
+     */
+    virtual void synchEnter() =0;
+
+    /**
+     * Leave synchronization mutex.
+     */
+    virtual void synchLeave() =0;
+
+    /**
+     * Inform about a PBX enrollment request.
+     *
+     * Please refer to chapter 8.3 ff to get more details about PBX
+     * enrollment and SAS relay.
+     *
+     * <b>Note:</b> PBX enrollement is not yet fully supported by GNU
+     * ZRTP.
+     *
+     * @param info Give some information to the user about the PBX
+     *    requesting an enrollment.
+     */
+    virtual void zrtpAskEnrollment(GnuZrtpCodes::InfoEnrollment info) =0;
+
+    /**
+     * Inform about PBX enrollment result.
+     *
+     * Informs the use about the acceptance or denial of an PBX enrollment
+     * request
+     *
+     * <b>Note:</b> PBX enrollement is not yet fully supported by GNU
+     * ZRTP.
+     *
+     * @param info information to the user about the result
+     *    of an enrollment.
+     */
+    virtual void zrtpInformEnrollment(GnuZrtpCodes::InfoEnrollment info) =0;
+
+    /**
+     * Request a SAS signature.
+     *
+     * After ZRTP was able to compute the Short Authentication String
+     * (SAS) it calls this method. The client may now use an
+     * approriate method to sign the SAS. The client may use
+     * ZrtpQueue#setSignatureData() to store the signature data an
+     * enable signature transmission to the other peer. Refer to
+     * chapter 8.2 of ZRTP specification.
+     *
+     * <b>Note:</b> SAS signing is not yet fully supported by GNU
+     * ZRTP.
+     *
+     * @param sasHash
+     *    The SAS hash to sign.
+     *
+     */
+    virtual void signSAS(uint8_t* sasHash) =0;
+
+    /**
+     * ZRTPQueue calls this method to request a SAS signature check.
+     *
+     * After ZRTP received a SAS signature in one of the Confirm packets it
+     * call this method. The client may use <code>getSignatureLength()</code>
+     * and <code>getSignatureData()</code>of ZrtpQueue to get the signature
+     * data and perform the signature check. Refer to chapter 8.2 of ZRTP
+     * specification.
+     *
+     * If the signature check fails the client may return false to ZRTP. In
+     * this case ZRTP signals an error to the other peer and terminates
+     * the ZRTP handshake.
+     *
+     * <b>Note:</b> SAS signing is not yet fully supported by GNU
+     * ZRTP.
+     *
+     * @param sasHash
+     *    The SAS hash that was signed by the other peer.
+     * @return
+     *    true if the signature was ok, false otherwise.
+     *
+     */
+    virtual bool checkSASSignature(uint8_t* sasHash) =0;
+};
+
+#endif // ZRTPCALLBACK
+
+/**
+ * @}
+ */
+/** EMACS **
+ * Local variables:
+ * mode: c++
+ * c-default-style: ellemtel
+ * c-basic-offset: 4
+ * End:
+ */