Merge pull request #3235 from jeannotlapin/pr1813

Add Dtls Srtp support (RFC5764)
diff --git a/ChangeLog.d/feature-dtls-srtp.txt b/ChangeLog.d/feature-dtls-srtp.txt
new file mode 100644
index 0000000..8b9186b
--- /dev/null
+++ b/ChangeLog.d/feature-dtls-srtp.txt
@@ -0,0 +1,2 @@
+Features
+* Add support for DTLS-SRTP as defined in RFC 5764. Contributed by Johan Pascal, improved by Ron Eldor.
diff --git a/include/mbedtls/check_config.h b/include/mbedtls/check_config.h
index 120c1d3..fd979db 100644
--- a/include/mbedtls/check_config.h
+++ b/include/mbedtls/check_config.h
@@ -871,6 +871,10 @@
 #endif /* MBEDTLS_DEPRECATED_REMOVED */
 #endif /* MBEDTLS_SSL_HW_RECORD_ACCEL */
 
+#if defined(MBEDTLS_SSL_DTLS_SRTP) && ( !defined(MBEDTLS_SSL_PROTO_DTLS) )
+#error "MBEDTLS_SSL_DTLS_SRTP defined, but not all prerequisites"
+#endif
+
 /*
  * Avoid warning from -pedantic. This is a convenient place for this
  * workaround since this is included by every single file before the
diff --git a/include/mbedtls/config.h b/include/mbedtls/config.h
index 48e8855..2ac2cc6 100644
--- a/include/mbedtls/config.h
+++ b/include/mbedtls/config.h
@@ -1813,6 +1813,37 @@
 #define MBEDTLS_SSL_DTLS_HELLO_VERIFY
 
 /**
+ * \def MBEDTLS_SSL_DTLS_SRTP
+ *
+ * Enable support for negotation of DTLS-SRTP (RFC 5764)
+ * through the use_srtp extension.
+ *
+ * \note This feature provides the minimum functionality required
+ * to negotiate the use of DTLS-SRTP and to allow the derivation of
+ * the associated SRTP packet protection key material.
+ * In particular, the SRTP packet protection itself, as well as the
+ * demultiplexing of RTP and DTLS packets at the datagram layer
+ * (see Section 5 of RFC 5764), are not handled by this feature.
+ * Instead, after successful completion of a handshake negotiating
+ * the use of DTLS-SRTP, the extended key exporter API
+ * mbedtls_ssl_conf_export_keys_ext_cb() should be used to implement
+ * the key exporter described in Section 4.2 of RFC 5764 and RFC 5705
+ * (this is implemented in the SSL example programs).
+ * The resulting key should then be passed to an SRTP stack.
+ *
+ * Setting this option enables the runtime API
+ * mbedtls_ssl_conf_dtls_srtp_protection_profiles()
+ * through which the supported DTLS-SRTP protection
+ * profiles can be configured. You must call this API at
+ * runtime if you wish to negotiate the use of DTLS-SRTP.
+ *
+ * Requires: MBEDTLS_SSL_PROTO_DTLS
+ *
+ * Uncomment this to enable support for use_srtp extension.
+ */
+//#define MBEDTLS_SSL_DTLS_SRTP
+
+/**
  * \def MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE
  *
  * Enable server-side support for clients that reconnect from the same port.
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index a091261..1b4e163 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -214,6 +214,9 @@
 #define MBEDTLS_SSL_CERT_REQ_CA_LIST_ENABLED       1
 #define MBEDTLS_SSL_CERT_REQ_CA_LIST_DISABLED      0
 
+#define MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED    0
+#define MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED      1
+
 /*
  * Default range for DTLS retransmission timer value, in milliseconds.
  * RFC 6347 4.2.4.1 says from 1 second to 60 seconds.
@@ -393,6 +396,8 @@
 
 #define MBEDTLS_TLS_EXT_SIG_ALG                     13
 
+#define MBEDTLS_TLS_EXT_USE_SRTP                    14
+
 #define MBEDTLS_TLS_EXT_ALPN                        16
 
 #define MBEDTLS_TLS_EXT_ENCRYPT_THEN_MAC            22 /* 0x16 */
@@ -851,6 +856,41 @@
 #endif /* MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED &&
           !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
 
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+
+#define MBEDTLS_TLS_SRTP_MAX_MKI_LENGTH             255
+#define MBEDTLS_TLS_SRTP_MAX_PROFILE_LIST_LENGTH    4
+/*
+ * For code readability use a typedef for DTLS-SRTP profiles
+ *
+ * Use_srtp extension protection profiles values as defined in
+ * http://www.iana.org/assignments/srtp-protection/srtp-protection.xhtml
+ *
+ * Reminder: if this list is expanded mbedtls_ssl_check_srtp_profile_value
+ * must be updated too.
+ */
+#define MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80     ( (uint16_t) 0x0001)
+#define MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32     ( (uint16_t) 0x0002)
+#define MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80          ( (uint16_t) 0x0005)
+#define MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32          ( (uint16_t) 0x0006)
+/* This one is not iana defined, but for code readability. */
+#define MBEDTLS_TLS_SRTP_UNSET                      ( (uint16_t) 0x0000)
+
+typedef uint16_t mbedtls_ssl_srtp_profile;
+
+typedef struct mbedtls_dtls_srtp_info_t
+{
+    /*! The SRTP profile that was negotiated. */
+    mbedtls_ssl_srtp_profile chosen_dtls_srtp_profile;
+    /*! The length of mki_value. */
+    uint16_t mki_len;
+    /*! The mki_value used, with max size of 256 bytes. */
+    unsigned char mki_value[MBEDTLS_TLS_SRTP_MAX_MKI_LENGTH];
+}
+mbedtls_dtls_srtp_info;
+
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
+
 /*
  * This structure is used for storing current session data.
  *
@@ -1057,6 +1097,13 @@
     const char **alpn_list;         /*!< ordered list of protocols          */
 #endif
 
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+    /*! ordered list of supported srtp profile */
+    const mbedtls_ssl_srtp_profile *dtls_srtp_profile_list;
+    /*! number of supported profiles */
+    size_t dtls_srtp_profile_list_len;
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
+
     /*
      * Numerical settings (int then char)
      */
@@ -1137,9 +1184,12 @@
                                              *   record with unexpected CID
                                              *   should lead to failure.    */
 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+    unsigned int dtls_srtp_mki_support : 1; /* support having mki_value
+                                               in the use_srtp extension     */
+#endif
 };
 
-
 struct mbedtls_ssl_context
 {
     const mbedtls_ssl_config *conf; /*!< configuration information          */
@@ -1298,6 +1348,13 @@
     const char *alpn_chosen;    /*!<  negotiated protocol                   */
 #endif /* MBEDTLS_SSL_ALPN */
 
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+    /*
+     * use_srtp extension
+     */
+    mbedtls_dtls_srtp_info dtls_srtp_info;
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
+
     /*
      * Information for DTLS hello verify
      */
@@ -2032,6 +2089,8 @@
  *                  (Default: none.)
  *
  * \note            See \c mbedtls_ssl_export_keys_ext_t.
+ * \warning         Exported key material must not be used for any purpose
+ *                  before the (D)TLS handshake is completed
  *
  * \param conf      SSL configuration context
  * \param f_export_keys_ext Callback for exporting keys
@@ -3120,6 +3179,105 @@
 const char *mbedtls_ssl_get_alpn_protocol( const mbedtls_ssl_context *ssl );
 #endif /* MBEDTLS_SSL_ALPN */
 
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+#if defined(MBEDTLS_DEBUG_C)
+static inline const char *mbedtls_ssl_get_srtp_profile_as_string( mbedtls_ssl_srtp_profile profile )
+{
+    switch( profile )
+    {
+        case MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80:
+            return( "MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80" );
+        case MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32:
+            return( "MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32" );
+        case MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80:
+            return( "MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80" );
+        case MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32:
+            return( "MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32" );
+        default: break;
+    }
+    return( "" );
+}
+#endif /* MBEDTLS_DEBUG_C */
+/**
+ * \brief                   Manage support for mki(master key id) value
+ *                          in use_srtp extension.
+ *                          MKI is an optional part of SRTP used for key management
+ *                          and re-keying. See RFC3711 section 3.1 for details.
+ *                          The default value is
+ *                          #MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED.
+ *
+ * \param conf              The SSL configuration to manage mki support.
+ * \param support_mki_value Enable or disable mki usage. Values are
+ *                          #MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED
+ *                          or #MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED.
+ */
+void mbedtls_ssl_conf_srtp_mki_value_supported( mbedtls_ssl_config *conf,
+                                                int support_mki_value );
+
+/**
+ * \brief                   Set the supported DTLS-SRTP protection profiles.
+ *
+ * \param conf              SSL configuration
+ * \param profiles          Pointer to a List of MBEDTLS_TLS_SRTP_UNSET terminated
+ *                          supported protection profiles
+ *                          in decreasing preference order.
+ *                          The pointer to the list is recorded by the library
+ *                          for later reference as required, so the lifetime
+ *                          of the table must be at least as long as the lifetime
+ *                          of the SSL configuration structure.
+ *                          The list must not hold more than
+ *                          MBEDTLS_TLS_SRTP_MAX_PROFILE_LIST_LENGTH elements
+ *                          (excluding the terminating MBEDTLS_TLS_SRTP_UNSET).
+ *
+ * \return                  0 on success
+ * \return                  #MBEDTLS_ERR_SSL_BAD_INPUT_DATA when the list of
+ *                          protection profiles is incorrect.
+ */
+int mbedtls_ssl_conf_dtls_srtp_protection_profiles
+                               ( mbedtls_ssl_config *conf,
+                                 const mbedtls_ssl_srtp_profile *profiles );
+
+/**
+ * \brief                  Set the mki_value for the current DTLS-SRTP session.
+ *
+ * \param ssl              SSL context to use.
+ * \param mki_value        The MKI value to set.
+ * \param mki_len          The length of the MKI value.
+ *
+ * \note                   This function is relevant on client side only.
+ *                         The server discovers the mki value during handshake.
+ *                         A mki value set on server side using this function
+ *                         is ignored.
+ *
+ * \return                 0 on success
+ * \return                 #MBEDTLS_ERR_SSL_BAD_INPUT_DATA
+ * \return                 #MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE
+ */
+int mbedtls_ssl_dtls_srtp_set_mki_value( mbedtls_ssl_context *ssl,
+                                         unsigned char *mki_value,
+                                         uint16_t mki_len );
+/**
+ * \brief                  Get the negotiated DTLS-SRTP informations:
+ *                         Protection profile and MKI value.
+ *
+ * \warning                This function must be called after the handshake is
+ *                         completed. The value returned by this function must
+ *                         not be trusted or acted upon before the handshake completes.
+ *
+ * \param ssl              The SSL context to query.
+ * \param dtls_srtp_info   The negotiated DTLS-SRTP informations:
+ *                         - Protection profile in use.
+ *                         A direct mapping of the iana defined value for protection
+ *                         profile on an uint16_t.
+                   http://www.iana.org/assignments/srtp-protection/srtp-protection.xhtml
+ *                         #MBEDTLS_TLS_SRTP_UNSET if the use of SRTP was not negotiated
+ *                         or peer's Hello packet was not parsed yet.
+ *                         - mki size and value( if size is > 0 ).
+ */
+void mbedtls_ssl_get_dtls_srtp_negotiation_result( const mbedtls_ssl_context *ssl,
+                                                   mbedtls_dtls_srtp_info *dtls_srtp_info );
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
+
 /**
  * \brief          Set the maximum supported version sent from the client side
  *                 and/or accepted at the server side
diff --git a/include/mbedtls/ssl_internal.h b/include/mbedtls/ssl_internal.h
index 7b78c73..1dc9648 100644
--- a/include/mbedtls/ssl_internal.h
+++ b/include/mbedtls/ssl_internal.h
@@ -1095,6 +1095,23 @@
                                 mbedtls_md_type_t md );
 #endif
 
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+static inline mbedtls_ssl_srtp_profile mbedtls_ssl_check_srtp_profile_value
+                                                    ( const uint16_t srtp_profile_value )
+{
+    switch( srtp_profile_value )
+    {
+        case MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80:
+        case MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32:
+        case MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80:
+        case MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32:
+            return srtp_profile_value;
+        default: break;
+    }
+    return( MBEDTLS_TLS_SRTP_UNSET );
+}
+#endif
+
 #if defined(MBEDTLS_X509_CRT_PARSE_C)
 static inline mbedtls_pk_context *mbedtls_ssl_own_key( mbedtls_ssl_context *ssl )
 {
diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index 083b720..76be8ab 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -756,6 +756,126 @@
 }
 #endif /* MBEDTLS_SSL_ALPN */
 
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+static int ssl_write_use_srtp_ext( mbedtls_ssl_context *ssl,
+                                   unsigned char *buf,
+                                   const unsigned char *end,
+                                   size_t *olen )
+{
+    unsigned char *p = buf;
+    size_t protection_profiles_index = 0, ext_len = 0;
+    uint16_t mki_len = 0, profile_value = 0;
+
+    *olen = 0;
+
+    if( ( ssl->conf->transport != MBEDTLS_SSL_TRANSPORT_DATAGRAM ) ||
+        ( ssl->conf->dtls_srtp_profile_list == NULL ) ||
+        ( ssl->conf->dtls_srtp_profile_list_len == 0 ) )
+    {
+        return( 0 );
+    }
+
+    /* RFC 5764 section 4.1.1
+     * uint8 SRTPProtectionProfile[2];
+     *
+     * struct {
+     *   SRTPProtectionProfiles SRTPProtectionProfiles;
+     *   opaque srtp_mki<0..255>;
+     * } UseSRTPData;
+     * SRTPProtectionProfile SRTPProtectionProfiles<2..2^16-1>;
+     */
+    if( ssl->conf->dtls_srtp_mki_support == MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED )
+    {
+        mki_len = ssl->dtls_srtp_info.mki_len;
+    }
+    /* Extension length = 2 bytes for profiles length,
+     *                    ssl->conf->dtls_srtp_profile_list_len * 2 (each profile is 2 bytes length ),
+     *                    1 byte for srtp_mki vector length and the mki_len value
+     */
+    ext_len = 2 + 2 * ( ssl->conf->dtls_srtp_profile_list_len ) + 1 + mki_len;
+
+    MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, adding use_srtp extension" ) );
+
+    /* Check there is room in the buffer for the extension + 4 bytes
+     * - the extension tag (2 bytes)
+     * - the extension length (2 bytes)
+     */
+    MBEDTLS_SSL_CHK_BUF_PTR( p, end, ext_len + 4 );
+
+    *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_USE_SRTP >> 8 ) & 0xFF );
+    *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_USE_SRTP      ) & 0xFF );
+
+
+    *p++ = (unsigned char)( ( ( ext_len & 0xFF00 ) >> 8 ) & 0xFF );
+    *p++ = (unsigned char)( ext_len & 0xFF );
+
+    /* protection profile length: 2*(ssl->conf->dtls_srtp_profile_list_len) */
+    /* micro-optimization:
+     * the list size is limited to MBEDTLS_TLS_SRTP_MAX_PROFILE_LIST_LENGTH
+     * which is lower than 127, so the upper byte of the length is always 0
+     * For the documentation, the more generic code is left in comments
+     * *p++ = (unsigned char)( ( ( 2 * ssl->conf->dtls_srtp_profile_list_len )
+     *                        >> 8 ) & 0xFF );
+     */
+    *p++ = 0;
+    *p++ = (unsigned char)( ( 2 * ssl->conf->dtls_srtp_profile_list_len )
+                            & 0xFF );
+
+    for( protection_profiles_index=0;
+         protection_profiles_index < ssl->conf->dtls_srtp_profile_list_len;
+         protection_profiles_index++ )
+    {
+        profile_value = mbedtls_ssl_check_srtp_profile_value
+                ( ssl->conf->dtls_srtp_profile_list[protection_profiles_index] );
+        if( profile_value != MBEDTLS_TLS_SRTP_UNSET )
+        {
+            MBEDTLS_SSL_DEBUG_MSG( 3, ( "ssl_write_use_srtp_ext, add profile: %04x",
+                                        profile_value ) );
+            *p++ = ( ( profile_value >> 8 ) & 0xFF );
+            *p++ = ( profile_value & 0xFF );
+        }
+        else
+        {
+            /*
+             * Note: we shall never arrive here as protection profiles
+             * is checked by mbedtls_ssl_conf_dtls_srtp_protection_profiles function
+             */
+            MBEDTLS_SSL_DEBUG_MSG( 3,
+                    ( "client hello, "
+                      "illegal DTLS-SRTP protection profile %d",
+                      ssl->conf->dtls_srtp_profile_list[protection_profiles_index]
+                    ) );
+            return( MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED );
+        }
+    }
+
+    *p++ = mki_len & 0xFF;
+
+    if( mki_len != 0 )
+    {
+        memcpy( p, ssl->dtls_srtp_info.mki_value, mki_len );
+        /*
+         * Increment p to point to the current position.
+         */
+        p += mki_len;
+        MBEDTLS_SSL_DEBUG_BUF( 3, "sending mki",  ssl->dtls_srtp_info.mki_value,
+                               ssl->dtls_srtp_info.mki_len );
+    }
+
+    /*
+     * total extension length: extension type (2 bytes)
+     *                         + extension length (2 bytes)
+     *                         + protection profile length (2 bytes)
+     *                         + 2 * number of protection profiles
+     *                         + srtp_mki vector length(1 byte)
+     *                         + mki value
+     */
+    *olen = p - buf;
+
+    return( 0 );
+}
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
+
 /*
  * Generate random bytes for ClientHello
  */
@@ -1277,6 +1397,16 @@
     ext_len += olen;
 #endif
 
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+    if( ( ret = ssl_write_use_srtp_ext( ssl, p + 2 + ext_len,
+                                        end, &olen ) ) != 0 )
+    {
+        MBEDTLS_SSL_DEBUG_RET( 1, "ssl_write_use_srtp_ext", ret );
+        return( ret );
+    }
+    ext_len += olen;
+#endif
+
 #if defined(MBEDTLS_SSL_SESSION_TICKETS)
     if( ( ret = ssl_write_session_ticket_ext( ssl, p + 2 + ext_len,
                                               end, &olen ) ) != 0 )
@@ -1710,6 +1840,123 @@
 }
 #endif /* MBEDTLS_SSL_ALPN */
 
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+static int ssl_parse_use_srtp_ext( mbedtls_ssl_context *ssl,
+                                   const unsigned char *buf,
+                                   size_t len )
+{
+    mbedtls_ssl_srtp_profile server_protection = MBEDTLS_TLS_SRTP_UNSET;
+    size_t i, mki_len = 0;
+    uint16_t server_protection_profile_value = 0;
+
+    /* If use_srtp is not configured, just ignore the extension */
+    if( ( ssl->conf->transport != MBEDTLS_SSL_TRANSPORT_DATAGRAM ) ||
+        ( ssl->conf->dtls_srtp_profile_list == NULL ) ||
+        ( ssl->conf->dtls_srtp_profile_list_len == 0 ) )
+        return( 0 );
+
+    /* RFC 5764 section 4.1.1
+     * uint8 SRTPProtectionProfile[2];
+     *
+     * struct {
+     *   SRTPProtectionProfiles SRTPProtectionProfiles;
+     *   opaque srtp_mki<0..255>;
+     * } UseSRTPData;
+
+     * SRTPProtectionProfile SRTPProtectionProfiles<2..2^16-1>;
+     *
+     */
+    if( ssl->conf->dtls_srtp_mki_support == MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED )
+    {
+        mki_len = ssl->dtls_srtp_info.mki_len;
+    }
+
+    /*
+     * Length is 5 + optional mki_value : one protection profile length (2 bytes)
+     *                                      + protection profile (2 bytes)
+     *                                      + mki_len(1 byte)
+     *                                      and optional srtp_mki
+     */
+    if( ( len < 5 ) || ( len != ( buf[4] + 5u ) ) )
+        return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
+
+    /*
+     * get the server protection profile
+     */
+
+    /*
+     * protection profile length must be 0x0002 as we must have only
+     * one protection profile in server Hello
+     */
+    if( (  buf[0] != 0 ) || ( buf[1] != 2 ) )
+        return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
+
+    server_protection_profile_value = ( buf[2] << 8 ) | buf[3];
+    server_protection = mbedtls_ssl_check_srtp_profile_value(
+                    server_protection_profile_value );
+    if( server_protection != MBEDTLS_TLS_SRTP_UNSET )
+    {
+        MBEDTLS_SSL_DEBUG_MSG( 3, ( "found srtp profile: %s",
+                                      mbedtls_ssl_get_srtp_profile_as_string(
+                                              server_protection ) ) );
+    }
+
+    ssl->dtls_srtp_info.chosen_dtls_srtp_profile = MBEDTLS_TLS_SRTP_UNSET;
+
+    /*
+     * Check we have the server profile in our list
+     */
+    for( i=0; i < ssl->conf->dtls_srtp_profile_list_len; i++)
+    {
+        if( server_protection == ssl->conf->dtls_srtp_profile_list[i] )
+        {
+            ssl->dtls_srtp_info.chosen_dtls_srtp_profile = ssl->conf->dtls_srtp_profile_list[i];
+            MBEDTLS_SSL_DEBUG_MSG( 3, ( "selected srtp profile: %s",
+                                      mbedtls_ssl_get_srtp_profile_as_string(
+                                              server_protection ) ) );
+            break;
+        }
+    }
+
+    /* If no match was found : server problem, it shall never answer with incompatible profile */
+    if( ssl->dtls_srtp_info.chosen_dtls_srtp_profile == MBEDTLS_TLS_SRTP_UNSET )
+    {
+        mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
+                                        MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE );
+        return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
+    }
+
+    /* If server does not use mki in its reply, make sure the client won't keep
+     * one as negotiated */
+    if( len == 5 )
+    {
+        ssl->dtls_srtp_info.mki_len = 0;
+    }
+
+    /*
+     * RFC5764:
+     *  If the client detects a nonzero-length MKI in the server's response
+     *  that is different than the one the client offered, then the client
+     *  MUST abort the handshake and SHOULD send an invalid_parameter alert.
+     */
+    if( len > 5  && ( buf[4] != mki_len ||
+        ( memcmp( ssl->dtls_srtp_info.mki_value, &buf[5], mki_len ) ) ) )
+    {
+        mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
+                                        MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER );
+        return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
+    }
+#if defined (MBEDTLS_DEBUG_C)
+    if( len > 5 )
+    {
+        MBEDTLS_SSL_DEBUG_BUF( 3, "received mki", ssl->dtls_srtp_info.mki_value,
+                                                  ssl->dtls_srtp_info.mki_len );
+    }
+#endif
+    return( 0 );
+}
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
+
 /*
  * Parse HelloVerifyRequest.  Only called after verifying the HS type.
  */
@@ -2278,6 +2525,16 @@
             break;
 #endif /* MBEDTLS_SSL_ALPN */
 
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+        case MBEDTLS_TLS_EXT_USE_SRTP:
+            MBEDTLS_SSL_DEBUG_MSG( 3, ( "found use_srtp extension" ) );
+
+            if( ( ret = ssl_parse_use_srtp_ext( ssl, ext + 4, ext_size ) ) != 0 )
+                return( ret );
+
+            break;
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
+
         default:
             MBEDTLS_SSL_DEBUG_MSG( 3,
                 ( "unknown extension found: %d (ignoring)", ext_id ) );
diff --git a/library/ssl_srv.c b/library/ssl_srv.c
index 2e63fce..070a591 100644
--- a/library/ssl_srv.c
+++ b/library/ssl_srv.c
@@ -776,6 +776,126 @@
 }
 #endif /* MBEDTLS_SSL_ALPN */
 
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+static int ssl_parse_use_srtp_ext( mbedtls_ssl_context *ssl,
+                                   const unsigned char *buf,
+                                   size_t len )
+{
+    mbedtls_ssl_srtp_profile client_protection = MBEDTLS_TLS_SRTP_UNSET;
+    size_t i,j;
+    size_t profile_length;
+    uint16_t mki_length;
+    /*! 2 bytes for profile length and 1 byte for mki len */
+    const size_t size_of_lengths = 3;
+
+    /* If use_srtp is not configured, just ignore the extension */
+    if( ( ssl->conf->transport != MBEDTLS_SSL_TRANSPORT_DATAGRAM ) ||
+        ( ssl->conf->dtls_srtp_profile_list == NULL ) ||
+        ( ssl->conf->dtls_srtp_profile_list_len == 0 ) )
+    {
+        return( 0 );
+    }
+
+    /* RFC5764 section 4.1.1
+     * uint8 SRTPProtectionProfile[2];
+     *
+     * struct {
+     *   SRTPProtectionProfiles SRTPProtectionProfiles;
+     *   opaque srtp_mki<0..255>;
+     * } UseSRTPData;
+
+     * SRTPProtectionProfile SRTPProtectionProfiles<2..2^16-1>;
+     */
+
+    /*
+     * Min length is 5: at least one protection profile(2 bytes)
+     *                  and length(2 bytes) + srtp_mki length(1 byte)
+     * Check here that we have at least 2 bytes of protection profiles length
+     * and one of srtp_mki length
+     */
+    if( len < size_of_lengths )
+    {
+        mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
+                                        MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE );
+        return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO );
+    }
+
+   ssl->dtls_srtp_info.chosen_dtls_srtp_profile = MBEDTLS_TLS_SRTP_UNSET;
+
+    /* first 2 bytes are protection profile length(in bytes) */
+    profile_length = ( buf[0] << 8 ) | buf[1];
+    buf += 2;
+
+    /* The profile length cannot be bigger than input buffer size - lengths fields */
+    if( profile_length > len - size_of_lengths ||
+        profile_length % 2 != 0 ) /* profiles are 2 bytes long, so the length must be even */
+    {
+        mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
+                                        MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE );
+        return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO );
+    }
+    /*
+     * parse the extension list values are defined in
+     * http://www.iana.org/assignments/srtp-protection/srtp-protection.xhtml
+     */
+    for( j = 0; j < profile_length; j += 2 )
+    {
+        uint16_t protection_profile_value = buf[j] << 8 | buf[j + 1];
+        client_protection = mbedtls_ssl_check_srtp_profile_value( protection_profile_value );
+
+        if( client_protection != MBEDTLS_TLS_SRTP_UNSET )
+        {
+            MBEDTLS_SSL_DEBUG_MSG( 3, ( "found srtp profile: %s",
+                                    mbedtls_ssl_get_srtp_profile_as_string(
+                                            client_protection ) ) );
+        }
+        else
+        {
+            continue;
+        }
+        /* check if suggested profile is in our list */
+        for( i = 0; i < ssl->conf->dtls_srtp_profile_list_len; i++)
+        {
+            if( client_protection == ssl->conf->dtls_srtp_profile_list[i] )
+            {
+                ssl->dtls_srtp_info.chosen_dtls_srtp_profile = ssl->conf->dtls_srtp_profile_list[i];
+                MBEDTLS_SSL_DEBUG_MSG( 3, ( "selected srtp profile: %s",
+                                            mbedtls_ssl_get_srtp_profile_as_string(
+                                                    client_protection ) ) );
+                break;
+            }
+        }
+        if( ssl->dtls_srtp_info.chosen_dtls_srtp_profile != MBEDTLS_TLS_SRTP_UNSET )
+            break;
+    }
+    buf += profile_length; /* buf points to the mki length */
+    mki_length = *buf;
+    buf++;
+
+    if( mki_length > MBEDTLS_TLS_SRTP_MAX_MKI_LENGTH ||
+        mki_length + profile_length + size_of_lengths != len )
+    {
+        mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
+                                        MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE );
+        return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO );
+    }
+
+    /* Parse the mki only if present and mki is supported locally */
+    if( ssl->conf->dtls_srtp_mki_support == MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED &&
+          mki_length > 0 )
+    {
+        ssl->dtls_srtp_info.mki_len = mki_length;
+
+        memcpy( ssl->dtls_srtp_info.mki_value, buf, mki_length );
+
+        MBEDTLS_SSL_DEBUG_BUF( 3, "using mki",  ssl->dtls_srtp_info.mki_value,
+                                                ssl->dtls_srtp_info.mki_len );
+    }
+
+    return( 0 );
+}
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
+
 /*
  * Auxiliary functions for ServerHello parsing and related actions
  */
@@ -1942,6 +2062,16 @@
                 break;
 #endif /* MBEDTLS_SSL_SESSION_TICKETS */
 
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+            case MBEDTLS_TLS_EXT_USE_SRTP:
+                MBEDTLS_SSL_DEBUG_MSG( 3, ( "found use_srtp extension" ) );
+
+                ret = ssl_parse_use_srtp_ext( ssl, ext + 4, ext_size );
+                if( ret != 0 )
+                    return( ret );
+                break;
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
+
             default:
                 MBEDTLS_SSL_DEBUG_MSG( 3, ( "unknown extension found: %d (ignoring)",
                                ext_id ) );
@@ -2500,6 +2630,78 @@
 }
 #endif /* MBEDTLS_ECDH_C || MBEDTLS_ECDSA_C */
 
+#if defined(MBEDTLS_SSL_DTLS_SRTP ) && defined(MBEDTLS_SSL_PROTO_DTLS)
+static void ssl_write_use_srtp_ext( mbedtls_ssl_context *ssl,
+                                    unsigned char *buf,
+                                    size_t *olen )
+{
+    size_t mki_len = 0, ext_len = 0;
+    uint16_t profile_value = 0;
+    const unsigned char *end = ssl->out_msg + MBEDTLS_SSL_OUT_CONTENT_LEN;
+
+    *olen = 0;
+
+    if( ( ssl->conf->transport != MBEDTLS_SSL_TRANSPORT_DATAGRAM ) ||
+        ( ssl->dtls_srtp_info.chosen_dtls_srtp_profile == MBEDTLS_TLS_SRTP_UNSET ) )
+    {
+        return;
+    }
+
+    MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, adding use_srtp extension" ) );
+
+    if( ssl->conf->dtls_srtp_mki_support == MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED )
+    {
+        mki_len = ssl->dtls_srtp_info.mki_len;
+    }
+
+    /* The extension total size is 9 bytes :
+     * - 2 bytes for the extension tag
+     * - 2 bytes for the total size
+     * - 2 bytes for the protection profile length
+     * - 2 bytes for the protection profile
+     * - 1 byte for the mki length
+     * +  the actual mki length
+     * Check we have enough room in the output buffer */
+    if( (size_t)( end - buf ) < mki_len + 9 )
+    {
+        MBEDTLS_SSL_DEBUG_MSG( 1, ( "buffer too small" ) );
+        return;
+    }
+
+    /* extension */
+    buf[0] = (unsigned char)( ( MBEDTLS_TLS_EXT_USE_SRTP >> 8 ) & 0xFF );
+    buf[1] = (unsigned char)( ( MBEDTLS_TLS_EXT_USE_SRTP      ) & 0xFF );
+    /*
+     * total length 5 and mki value: only one profile(2 bytes)
+     *              and length(2 bytes) and srtp_mki  )
+     */
+    ext_len = 5 + mki_len;
+    buf[2] = (unsigned char)( ( ext_len >> 8 ) & 0xFF );
+    buf[3] = (unsigned char)( ext_len & 0xFF );
+
+    /* protection profile length: 2 */
+    buf[4] = 0x00;
+    buf[5] = 0x02;
+    profile_value = mbedtls_ssl_check_srtp_profile_value(
+                                ssl->dtls_srtp_info.chosen_dtls_srtp_profile );
+    if( profile_value != MBEDTLS_TLS_SRTP_UNSET )
+    {
+        buf[6] = (unsigned char)( ( profile_value >> 8 ) & 0xFF );
+        buf[7] = (unsigned char)( profile_value & 0xFF );
+    }
+    else
+    {
+        MBEDTLS_SSL_DEBUG_MSG( 1, ( "use_srtp extension invalid profile" ) );
+        return;
+    }
+
+    buf[8] = mki_len & 0xFF;
+    memcpy( &buf[9], ssl->dtls_srtp_info.mki_value, mki_len );
+
+    *olen = 9 + mki_len;
+}
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
+
 #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY)
 static int ssl_write_hello_verify_request( mbedtls_ssl_context *ssl )
 {
@@ -2788,6 +2990,11 @@
     ext_len += olen;
 #endif
 
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+    ssl_write_use_srtp_ext( ssl, p + 2 + ext_len, &olen );
+    ext_len += olen;
+#endif
+
     MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, total extension length: %d", ext_len ) );
 
     if( ext_len > 0 )
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index 34953f2..7cb5b8c 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -3859,6 +3859,10 @@
 
     mbedtls_ssl_reset_in_out_pointers( ssl );
 
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+    memset( &ssl->dtls_srtp_info, 0, sizeof(ssl->dtls_srtp_info) );
+#endif
+
     if( ( ret = ssl_handshake_init( ssl ) ) != 0 )
         goto error;
 
@@ -4685,6 +4689,86 @@
 }
 #endif /* MBEDTLS_SSL_ALPN */
 
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+void mbedtls_ssl_conf_srtp_mki_value_supported( mbedtls_ssl_config *conf,
+                                                int support_mki_value )
+{
+    conf->dtls_srtp_mki_support = support_mki_value;
+}
+
+int mbedtls_ssl_dtls_srtp_set_mki_value( mbedtls_ssl_context *ssl,
+                                         unsigned char *mki_value,
+                                         uint16_t mki_len )
+{
+    if( mki_len > MBEDTLS_TLS_SRTP_MAX_MKI_LENGTH )
+    {
+        return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
+    }
+
+    if( ssl->conf->dtls_srtp_mki_support == MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED )
+    {
+        return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE );
+    }
+
+    memcpy( ssl->dtls_srtp_info.mki_value, mki_value, mki_len );
+    ssl->dtls_srtp_info.mki_len = mki_len;
+    return( 0 );
+}
+
+int mbedtls_ssl_conf_dtls_srtp_protection_profiles( mbedtls_ssl_config *conf,
+                                                    const mbedtls_ssl_srtp_profile *profiles )
+{
+    const mbedtls_ssl_srtp_profile *p;
+    size_t list_size = 0;
+
+    /* check the profiles list: all entry must be valid,
+     * its size cannot be more than the total number of supported profiles, currently 4 */
+    for( p = profiles; *p != MBEDTLS_TLS_SRTP_UNSET &&
+                       list_size <= MBEDTLS_TLS_SRTP_MAX_PROFILE_LIST_LENGTH;
+         p++ )
+    {
+        if( mbedtls_ssl_check_srtp_profile_value( *p ) != MBEDTLS_TLS_SRTP_UNSET )
+        {
+            list_size++;
+        }
+        else
+        {
+            /* unsupported value, stop parsing and set the size to an error value */
+            list_size = MBEDTLS_TLS_SRTP_MAX_PROFILE_LIST_LENGTH + 1;
+        }
+    }
+
+    if( list_size > MBEDTLS_TLS_SRTP_MAX_PROFILE_LIST_LENGTH )
+    {
+                conf->dtls_srtp_profile_list = NULL;
+                conf->dtls_srtp_profile_list_len = 0;
+                return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
+    }
+
+    conf->dtls_srtp_profile_list = profiles;
+    conf->dtls_srtp_profile_list_len = list_size;
+
+    return( 0 );
+}
+
+void mbedtls_ssl_get_dtls_srtp_negotiation_result( const mbedtls_ssl_context *ssl,
+                                                   mbedtls_dtls_srtp_info *dtls_srtp_info )
+{
+    dtls_srtp_info->chosen_dtls_srtp_profile = ssl->dtls_srtp_info.chosen_dtls_srtp_profile;
+    /* do not copy the mki value if there is no chosen profile */
+    if( dtls_srtp_info->chosen_dtls_srtp_profile == MBEDTLS_TLS_SRTP_UNSET )
+    {
+        dtls_srtp_info->mki_len = 0;
+    }
+    else
+    {
+        dtls_srtp_info->mki_len = ssl->dtls_srtp_info.mki_len;
+        memcpy( dtls_srtp_info->mki_value, ssl->dtls_srtp_info.mki_value,
+                ssl->dtls_srtp_info.mki_len );
+    }
+}
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
+
 void mbedtls_ssl_conf_max_version( mbedtls_ssl_config *conf, int major, int minor )
 {
     conf->max_major_ver = major;
diff --git a/library/version_features.c b/library/version_features.c
index 62b0553..42ccaf9 100644
--- a/library/version_features.c
+++ b/library/version_features.c
@@ -534,6 +534,9 @@
 #if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY)
     "MBEDTLS_SSL_DTLS_HELLO_VERIFY",
 #endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY */
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+    "MBEDTLS_SSL_DTLS_SRTP",
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
 #if defined(MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE)
     "MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE",
 #endif /* MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE */
diff --git a/programs/ssl/ssl_client2.c b/programs/ssl/ssl_client2.c
index b9047df..54cdd7d 100644
--- a/programs/ssl/ssl_client2.c
+++ b/programs/ssl/ssl_client2.c
@@ -150,6 +150,9 @@
 #define DFL_NSS_KEYLOG_FILE     NULL
 #define DFL_SKIP_CLOSE_NOTIFY   0
 #define DFL_QUERY_CONFIG_MODE   0
+#define DFL_USE_SRTP            0
+#define DFL_SRTP_FORCE_PROFILE  0
+#define DFL_SRTP_MKI            ""
 
 #define GET_REQUEST "GET %s HTTP/1.0\r\nExtra-header: "
 #define GET_REQUEST_END "\r\n\r\n"
@@ -254,10 +257,26 @@
     "                             This cannot be used with eap_tls=1\n"
 #define USAGE_NSS_KEYLOG_FILE                               \
     "    nss_keylog_file=%%s\n"
-#else
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+#define USAGE_SRTP \
+    "    use_srtp=%%d         default: 0 (disabled)\n" \
+    "                          This cannot be used with eap_tls=1 or "\
+    "                          nss_keylog=1\n"             \
+    "    srtp_force_profile=%%d  default: 0 (all enabled)\n"   \
+    "                        available profiles:\n"       \
+    "                        1 - SRTP_AES128_CM_HMAC_SHA1_80\n"  \
+    "                        2 - SRTP_AES128_CM_HMAC_SHA1_32\n"  \
+    "                        3 - SRTP_NULL_HMAC_SHA1_80\n"       \
+    "                        4 - SRTP_NULL_HMAC_SHA1_32\n"       \
+    "    mki=%%s              default: \"\" (in hex, without 0x)\n"
+#else /* MBEDTLS_SSL_DTLS_SRTP */
+#define USAGE_SRTP ""
+#endif
+#else /* MBEDTLS_SSL_EXPORT_KEYS */
 #define USAGE_EAP_TLS ""
 #define USAGE_NSS_KEYLOG ""
 #define USAGE_NSS_KEYLOG_FILE ""
+#define USAGE_SRTP ""
 #endif /* MBEDTLS_SSL_EXPORT_KEYS */
 
 #if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
@@ -407,6 +426,7 @@
     "\n"                                                    \
     USAGE_DTLS                                              \
     USAGE_CID                                               \
+    USAGE_SRTP                                              \
     "\n"
 #define USAGE2 \
     "    auth_mode=%%s        default: (library default: none)\n" \
@@ -541,6 +561,9 @@
     int reproducible;           /* make communication reproducible          */
     int skip_close_notify;      /* skip sending the close_notify alert      */
     int query_config_mode;      /* whether to read config                   */
+    int use_srtp;               /* Support SRTP                             */
+    int force_srtp_profile;     /* SRTP protection profile to use or all    */
+    const char *mki;            /* The dtls mki value to use                */
 } opt;
 
 int query_config( const char *config );
@@ -655,7 +678,49 @@
                               sizeof( nss_keylog_line ) );
     return( ret );
 }
-#endif
+
+#if defined( MBEDTLS_SSL_DTLS_SRTP )
+/* Supported SRTP mode needs a maximum of :
+ * - 16 bytes for key (AES-128)
+ * - 14 bytes SALT
+ * One for sender, one for receiver context
+ */
+#define MBEDTLS_TLS_SRTP_MAX_KEY_MATERIAL_LENGTH    60
+typedef struct dtls_srtp_keys
+{
+    unsigned char master_secret[48];
+    unsigned char randbytes[64];
+    mbedtls_tls_prf_types tls_prf_type;
+} dtls_srtp_keys;
+
+static int dtls_srtp_key_derivation( void *p_expkey,
+                                     const unsigned char *ms,
+                                     const unsigned char *kb,
+                                     size_t maclen,
+                                     size_t keylen,
+                                     size_t ivlen,
+                                     const unsigned char client_random[32],
+                                     const unsigned char server_random[32],
+                                     mbedtls_tls_prf_types tls_prf_type )
+{
+    dtls_srtp_keys *keys = (dtls_srtp_keys *)p_expkey;
+
+    ( ( void ) kb );
+    memcpy( keys->master_secret, ms, sizeof( keys->master_secret ) );
+    memcpy( keys->randbytes, client_random, 32 );
+    memcpy( keys->randbytes + 32, server_random, 32 );
+    keys->tls_prf_type = tls_prf_type;
+
+    if( opt.debug_level > 2 )
+    {
+        mbedtls_printf( "exported maclen is %u\n", (unsigned) maclen );
+        mbedtls_printf( "exported keylen is %u\n", (unsigned) keylen );
+        mbedtls_printf( "exported ivlen is %u\n", (unsigned) ivlen );
+    }
+    return( 0 );
+}
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
+#endif /* MBEDTLS_SSL_EXPORT_KEYS */
 
 static void my_debug( void *ctx, int level,
                       const char *file, int line,
@@ -1134,6 +1199,10 @@
     mbedtls_ecp_group_id curve_list[CURVE_LIST_SIZE];
     const mbedtls_ecp_curve_info *curve_cur;
 #endif
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+    unsigned char mki[MBEDTLS_TLS_SRTP_MAX_MKI_LENGTH];
+    size_t mki_len=0;
+#endif
 
     const char *pers = "ssl_client2";
 
@@ -1177,7 +1246,20 @@
     unsigned char eap_tls_iv[8];
     const char* eap_tls_label = "client EAP encryption";
     eap_tls_keys eap_tls_keying;
-#endif
+#if defined( MBEDTLS_SSL_DTLS_SRTP )
+    /*! master keys and master salt for SRTP generated during handshake */
+    unsigned char dtls_srtp_key_material[MBEDTLS_TLS_SRTP_MAX_KEY_MATERIAL_LENGTH];
+    const char* dtls_srtp_label = "EXTRACTOR-dtls_srtp";
+    dtls_srtp_keys dtls_srtp_keying;
+    const mbedtls_ssl_srtp_profile default_profiles[] = {
+        MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80,
+        MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32,
+        MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80,
+        MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32,
+        MBEDTLS_TLS_SRTP_UNSET
+    };
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
+#endif /* MBEDTLS_SSL_EXPORT_KEYS */
 
 #if defined(MBEDTLS_MEMORY_BUFFER_ALLOC_C)
     mbedtls_memory_buffer_alloc_init( alloc_buf, sizeof(alloc_buf) );
@@ -1304,6 +1386,9 @@
     opt.nss_keylog_file     = DFL_NSS_KEYLOG_FILE;
     opt.skip_close_notify   = DFL_SKIP_CLOSE_NOTIFY;
     opt.query_config_mode   = DFL_QUERY_CONFIG_MODE;
+    opt.use_srtp            = DFL_USE_SRTP;
+    opt.force_srtp_profile  = DFL_SRTP_FORCE_PROFILE;
+    opt.mki                 = DFL_SRTP_MKI;
 
     for( i = 1; i < argc; i++ )
     {
@@ -1730,6 +1815,18 @@
             if( opt.skip_close_notify < 0 || opt.skip_close_notify > 1 )
                 goto usage;
         }
+        else if( strcmp( p, "use_srtp" ) == 0 )
+        {
+            opt.use_srtp = atoi ( q );
+        }
+        else if( strcmp( p, "srtp_force_profile" ) == 0 )
+        {
+            opt.force_srtp_profile = atoi( q );
+        }
+        else if( strcmp( p, "mki" ) == 0 )
+        {
+            opt.mki = q;
+        }
         else
             goto usage;
     }
@@ -1837,7 +1934,6 @@
             opt.arc4 = MBEDTLS_SSL_ARC4_ENABLED;
         }
 
-
 #if defined(MBEDTLS_USE_PSA_CRYPTO)
         if( opt.psk_opaque != 0 )
         {
@@ -2240,6 +2336,36 @@
     }
 #endif
 
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+    if( opt.use_srtp == 1 )
+    {
+        if( opt.force_srtp_profile != 0 )
+        {
+            const mbedtls_ssl_srtp_profile forced_profile[] =
+                                        { opt.force_srtp_profile, MBEDTLS_TLS_SRTP_UNSET };
+            ret = mbedtls_ssl_conf_dtls_srtp_protection_profiles ( &conf, forced_profile );
+        }
+        else
+        {
+            ret = mbedtls_ssl_conf_dtls_srtp_protection_profiles ( &conf, default_profiles );
+        }
+
+        if( ret != 0 )
+        {
+            mbedtls_printf( " failed\n  ! "
+                            "mbedtls_ssl_conf_dtls_srtp_protection_profiles returned %d\n\n",
+                            ret );
+            goto exit;
+        }
+
+    }
+    else if( opt.force_srtp_profile != 0 )
+    {
+        mbedtls_printf( " failed\n  ! must enable use_srtp to force srtp profile\n\n" );
+        goto exit;
+    }
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
+
 #if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
     if( opt.trunc_hmac != DFL_TRUNC_HMAC )
         mbedtls_ssl_conf_truncated_hmac( &conf, opt.trunc_hmac );
@@ -2267,7 +2393,14 @@
                                              nss_keylog_export,
                                              NULL );
     }
-#endif
+#if defined( MBEDTLS_SSL_DTLS_SRTP )
+    else if( opt.use_srtp != 0 )
+    {
+        mbedtls_ssl_conf_export_keys_ext_cb( &conf, dtls_srtp_key_derivation,
+                                             &dtls_srtp_keying );
+    }
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
+#endif /* MBEDTLS_SSL_EXPORT_KEYS */
 
 #if defined(MBEDTLS_SSL_CBC_RECORD_SPLITTING)
     if( opt.recsplit != DFL_RECSPLIT )
@@ -2476,6 +2609,26 @@
         mbedtls_ecp_set_max_ops( opt.ec_max_ops );
 #endif
 
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+    if( opt.use_srtp != 0 && strlen( opt.mki ) != 0 )
+    {
+        if( mbedtls_test_unhexify( mki, sizeof( mki ),
+                                   opt.mki,&mki_len ) != 0 )
+        {
+            mbedtls_printf( "mki value not valid hex\n" );
+            goto exit;
+        }
+
+        mbedtls_ssl_conf_srtp_mki_value_supported( &conf, MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED );
+        if( ( ret = mbedtls_ssl_dtls_srtp_set_mki_value( &ssl, mki,
+                                                         (uint16_t) strlen( opt.mki ) / 2 ) ) != 0 )
+        {
+            mbedtls_printf( " failed\n  ! mbedtls_ssl_dtls_srtp_set_mki_value returned %d\n\n", ret );
+            goto exit;
+        }
+    }
+#endif
+
     mbedtls_printf( " ok\n" );
 
     /*
@@ -2597,7 +2750,74 @@
         }
         mbedtls_printf("\n");
     }
-#endif
+
+#if defined( MBEDTLS_SSL_DTLS_SRTP )
+    else if( opt.use_srtp != 0  )
+    {
+        size_t j = 0;
+        mbedtls_dtls_srtp_info dtls_srtp_negotiation_result;
+        mbedtls_ssl_get_dtls_srtp_negotiation_result( &ssl, &dtls_srtp_negotiation_result );
+
+        if( dtls_srtp_negotiation_result.chosen_dtls_srtp_profile
+                                == MBEDTLS_TLS_SRTP_UNSET )
+        {
+            mbedtls_printf( "    Unable to negotiate "
+                            "the use of DTLS-SRTP\n" );
+        }
+        else
+        {
+            if( ( ret = mbedtls_ssl_tls_prf( dtls_srtp_keying.tls_prf_type,
+                                             dtls_srtp_keying.master_secret,
+                                             sizeof( dtls_srtp_keying.master_secret ),
+                                             dtls_srtp_label,
+                                             dtls_srtp_keying.randbytes,
+                                             sizeof( dtls_srtp_keying.randbytes ),
+                                             dtls_srtp_key_material,
+                                             sizeof( dtls_srtp_key_material ) ) )
+                                             != 0 )
+            {
+                mbedtls_printf( " failed\n  ! mbedtls_ssl_tls_prf returned -0x%x\n\n",
+                                (unsigned int) -ret );
+                goto exit;
+            }
+
+            mbedtls_printf( "    DTLS-SRTP key material is:" );
+            for( j = 0; j < sizeof( dtls_srtp_key_material ); j++ )
+            {
+                if( j % 8 == 0 )
+                    mbedtls_printf( "\n    " );
+                mbedtls_printf( "%02x ", dtls_srtp_key_material[j] );
+            }
+            mbedtls_printf( "\n" );
+
+            /* produce a less readable output used to perform automatic checks
+             * - compare client and server output
+             * - interop test with openssl which client produces this kind of output
+             */
+            mbedtls_printf( "    Keying material: " );
+            for( j = 0; j < sizeof( dtls_srtp_key_material ); j++ )
+            {
+                mbedtls_printf( "%02X", dtls_srtp_key_material[j] );
+            }
+            mbedtls_printf( "\n" );
+
+            if ( dtls_srtp_negotiation_result.mki_len > 0 )
+            {
+                mbedtls_printf( "    DTLS-SRTP mki value: " );
+                for( j = 0; j < dtls_srtp_negotiation_result.mki_len; j++ )
+                {
+                    mbedtls_printf( "%02X", dtls_srtp_negotiation_result.mki_value[j] );
+                }
+            }
+            else
+            {
+                mbedtls_printf( "    DTLS-SRTP no mki value negotiated" );
+            }
+            mbedtls_printf( "\n" );
+        }
+    }
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
+#endif /* MBEDTLS_SSL_EXPORT_KEYS */
     if( opt.reconnect != 0 )
     {
         mbedtls_printf("  . Saving session for reuse..." );
diff --git a/programs/ssl/ssl_server2.c b/programs/ssl/ssl_server2.c
index a98aec1..ec3d6ad 100644
--- a/programs/ssl/ssl_server2.c
+++ b/programs/ssl/ssl_server2.c
@@ -183,6 +183,9 @@
 #define DFL_NSS_KEYLOG          0
 #define DFL_NSS_KEYLOG_FILE     NULL
 #define DFL_QUERY_CONFIG_MODE   0
+#define DFL_USE_SRTP            0
+#define DFL_SRTP_FORCE_PROFILE  0
+#define DFL_SRTP_SUPPORT_MKI    0
 
 #define LONG_RESPONSE "<p>01-blah-blah-blah-blah-blah-blah-blah-blah-blah\r\n" \
     "02-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah\r\n"  \
@@ -325,10 +328,24 @@
     "                             This cannot be used with eap_tls=1\n"
 #define USAGE_NSS_KEYLOG_FILE                               \
     "    nss_keylog_file=%%s\n"
-#else
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+#define USAGE_SRTP \
+    "    use_srtp=%%d         default: 0 (disabled)\n" \
+    "    srtp_force_profile=%%d  default: 0 (all enabled)\n"   \
+    "                        available profiles:\n"       \
+    "                        1 - SRTP_AES128_CM_HMAC_SHA1_80\n"  \
+    "                        2 - SRTP_AES128_CM_HMAC_SHA1_32\n"  \
+    "                        3 - SRTP_NULL_HMAC_SHA1_80\n"       \
+    "                        4 - SRTP_NULL_HMAC_SHA1_32\n"       \
+    "    support_mki=%%d     default: 0 (not supported)\n"
+#else /* MBEDTLS_SSL_DTLS_SRTP */
+#define USAGE_SRTP ""
+#endif
+#else /* MBEDTLS_SSL_EXPORT_KEYS */
 #define USAGE_EAP_TLS ""
 #define USAGE_NSS_KEYLOG ""
 #define USAGE_NSS_KEYLOG_FILE ""
+#define USAGE_SRTP ""
 #endif /* MBEDTLS_SSL_EXPORT_KEYS */
 
 #if defined(MBEDTLS_SSL_CACHE_C)
@@ -490,6 +507,7 @@
     "    read_timeout=%%d     default: 0 ms (no timeout)\n"    \
     "\n"                                                    \
     USAGE_DTLS                                              \
+    USAGE_SRTP                                              \
     USAGE_COOKIES                                           \
     USAGE_ANTI_REPLAY                                       \
     USAGE_BADMAC_LIMIT                                      \
@@ -645,6 +663,9 @@
                                  * after renegotiation                      */
     int reproducible;           /* make communication reproducible          */
     int query_config_mode;      /* whether to read config                   */
+    int use_srtp;               /* Support SRTP                             */
+    int force_srtp_profile;     /* SRTP protection profile to use or all    */
+    int support_mki;            /* The dtls mki mki support                 */
 } opt;
 
 int query_config( const char *config );
@@ -760,7 +781,49 @@
     return( ret );
 }
 
-#endif
+#if defined( MBEDTLS_SSL_DTLS_SRTP )
+/* Supported SRTP mode needs a maximum of :
+ * - 16 bytes for key (AES-128)
+ * - 14 bytes SALT
+ * One for sender, one for receiver context
+ */
+#define MBEDTLS_TLS_SRTP_MAX_KEY_MATERIAL_LENGTH    60
+typedef struct dtls_srtp_keys
+{
+    unsigned char master_secret[48];
+    unsigned char randbytes[64];
+    mbedtls_tls_prf_types tls_prf_type;
+} dtls_srtp_keys;
+
+static int dtls_srtp_key_derivation( void *p_expkey,
+                                     const unsigned char *ms,
+                                     const unsigned char *kb,
+                                     size_t maclen,
+                                     size_t keylen,
+                                     size_t ivlen,
+                                     const unsigned char client_random[32],
+                                     const unsigned char server_random[32],
+                                     mbedtls_tls_prf_types tls_prf_type )
+{
+    dtls_srtp_keys *keys = (dtls_srtp_keys *)p_expkey;
+
+    ( ( void ) kb );
+    memcpy( keys->master_secret, ms, sizeof( keys->master_secret ) );
+    memcpy( keys->randbytes, client_random, 32 );
+    memcpy( keys->randbytes + 32, server_random, 32 );
+    keys->tls_prf_type = tls_prf_type;
+
+    if( opt.debug_level > 2 )
+    {
+        mbedtls_printf( "exported maclen is %u\n", (unsigned) maclen );
+        mbedtls_printf( "exported keylen is %u\n", (unsigned) keylen );
+        mbedtls_printf( "exported ivlen is %u\n", (unsigned) ivlen );
+    }
+    return( 0 );
+}
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
+
+#endif /* MBEDTLS_SSL_EXPORT_KEYS */
 
 static void my_debug( void *ctx, int level,
                       const char *file, int line,
@@ -1792,7 +1855,6 @@
 #if defined(MBEDTLS_MEMORY_BUFFER_ALLOC_C)
     unsigned char alloc_buf[MEMORY_HEAP_SIZE];
 #endif
-
 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
     unsigned char cid[MBEDTLS_SSL_CID_IN_LEN_MAX];
     unsigned char cid_renego[MBEDTLS_SSL_CID_IN_LEN_MAX];
@@ -1815,7 +1877,20 @@
     unsigned char eap_tls_iv[8];
     const char* eap_tls_label = "client EAP encryption";
     eap_tls_keys eap_tls_keying;
-#endif
+#if defined( MBEDTLS_SSL_DTLS_SRTP )
+    /*! master keys and master salt for SRTP generated during handshake */
+     unsigned char dtls_srtp_key_material[MBEDTLS_TLS_SRTP_MAX_KEY_MATERIAL_LENGTH];
+     const char* dtls_srtp_label = "EXTRACTOR-dtls_srtp";
+     dtls_srtp_keys dtls_srtp_keying;
+     const mbedtls_ssl_srtp_profile default_profiles[] = {
+         MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80,
+         MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32,
+         MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80,
+         MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32,
+         MBEDTLS_TLS_SRTP_UNSET
+     };
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
+#endif /* MBEDTLS_SSL_EXPORT_KEYS */
 
 #if defined(MBEDTLS_MEMORY_BUFFER_ALLOC_C)
     mbedtls_memory_buffer_alloc_init( alloc_buf, sizeof(alloc_buf) );
@@ -1976,6 +2051,9 @@
     opt.nss_keylog          = DFL_NSS_KEYLOG;
     opt.nss_keylog_file     = DFL_NSS_KEYLOG_FILE;
     opt.query_config_mode   = DFL_QUERY_CONFIG_MODE;
+    opt.use_srtp            = DFL_USE_SRTP;
+    opt.force_srtp_profile  = DFL_SRTP_FORCE_PROFILE;
+    opt.support_mki         = DFL_SRTP_SUPPORT_MKI;
 
     for( i = 1; i < argc; i++ )
     {
@@ -2424,6 +2502,18 @@
         {
             opt.nss_keylog_file = q;
         }
+        else if( strcmp( p, "use_srtp" ) == 0 )
+        {
+            opt.use_srtp = atoi ( q );
+        }
+        else if( strcmp( p, "srtp_force_profile" ) == 0 )
+        {
+            opt.force_srtp_profile = atoi( q );
+        }
+        else if( strcmp( p, "support_mki" ) == 0 )
+        {
+            opt.support_mki = atoi( q );
+        }
         else
             goto usage;
     }
@@ -3028,7 +3118,7 @@
     {
         mbedtls_printf( " failed\n  ! mbedtls_ssl_conf_max_frag_len returned %d\n\n", ret );
         goto exit;
-    };
+    }
 #endif
 
 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
@@ -3058,6 +3148,38 @@
     }
 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
 
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+    if( opt.use_srtp == 1 )
+    {
+        if( opt.force_srtp_profile != 0 )
+        {
+            const mbedtls_ssl_srtp_profile forced_profile[] = { opt.force_srtp_profile, MBEDTLS_TLS_SRTP_UNSET };
+            ret = mbedtls_ssl_conf_dtls_srtp_protection_profiles( &conf, forced_profile );
+        }
+        else
+        {
+            ret = mbedtls_ssl_conf_dtls_srtp_protection_profiles( &conf, default_profiles );
+        }
+
+        if( ret != 0 )
+        {
+            mbedtls_printf( " failed\n  ! mbedtls_ssl_conf_dtls_srtp_protection_profiles returned %d\n\n", ret );
+            goto exit;
+        }
+
+        mbedtls_ssl_conf_srtp_mki_value_supported( &conf,
+                                                   opt.support_mki ?
+                                                   MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED :
+                                                   MBEDTLS_SSL_DTLS_SRTP_MKI_UNSUPPORTED );
+
+    }
+    else if( opt.force_srtp_profile != 0 )
+    {
+        mbedtls_printf( " failed\n  ! must enable use_srtp to force srtp profile\n\n" );
+        goto exit;
+    }
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
+
 #if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
     if( opt.trunc_hmac != DFL_TRUNC_HMAC )
         mbedtls_ssl_conf_truncated_hmac( &conf, opt.trunc_hmac );
@@ -3085,7 +3207,14 @@
                                              nss_keylog_export,
                                              NULL );
     }
-#endif
+#if defined( MBEDTLS_SSL_DTLS_SRTP )
+    else if( opt.use_srtp != 0 )
+    {
+        mbedtls_ssl_conf_export_keys_ext_cb( &conf, dtls_srtp_key_derivation,
+                                             &dtls_srtp_keying );
+    }
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
+#endif /* MBEDTLS_SSL_EXPORT_KEYS */
 
 #if defined(MBEDTLS_SSL_ALPN)
     if( opt.alpn_string != NULL )
@@ -3731,7 +3860,75 @@
         }
         mbedtls_printf("\n");
     }
-#endif
+
+#if defined( MBEDTLS_SSL_DTLS_SRTP )
+    else if( opt.use_srtp != 0  )
+    {
+        size_t j = 0;
+        mbedtls_dtls_srtp_info dtls_srtp_negotiation_result;
+        mbedtls_ssl_get_dtls_srtp_negotiation_result( &ssl, &dtls_srtp_negotiation_result );
+
+        if( dtls_srtp_negotiation_result.chosen_dtls_srtp_profile
+                                == MBEDTLS_TLS_SRTP_UNSET )
+        {
+            mbedtls_printf( "    Unable to negotiate "
+                            "the use of DTLS-SRTP\n" );
+        }
+        else
+        {
+            if( ( ret = mbedtls_ssl_tls_prf( dtls_srtp_keying.tls_prf_type,
+                                             dtls_srtp_keying.master_secret,
+                                             sizeof( dtls_srtp_keying.master_secret ),
+                                             dtls_srtp_label,
+                                             dtls_srtp_keying.randbytes,
+                                             sizeof( dtls_srtp_keying.randbytes ),
+                                             dtls_srtp_key_material,
+                                             sizeof( dtls_srtp_key_material ) ) )
+                                             != 0 )
+            {
+                mbedtls_printf( " failed\n  ! mbedtls_ssl_tls_prf returned -0x%x\n\n",
+                                (unsigned int) -ret );
+                goto exit;
+            }
+
+            mbedtls_printf( "    DTLS-SRTP key material is:" );
+            for( j = 0; j < sizeof( dtls_srtp_key_material ); j++ )
+            {
+                if( j % 8 == 0 )
+                    mbedtls_printf( "\n    " );
+                mbedtls_printf( "%02x ", dtls_srtp_key_material[j] );
+            }
+            mbedtls_printf( "\n" );
+
+            /* produce a less readable output used to perform automatic checks
+             * - compare client and server output
+             * - interop test with openssl which client produces this kind of output
+             */
+            mbedtls_printf( "    Keying material: " );
+            for( j = 0; j < sizeof( dtls_srtp_key_material ); j++ )
+            {
+                mbedtls_printf( "%02X", dtls_srtp_key_material[j] );
+            }
+            mbedtls_printf( "\n" );
+
+            if ( dtls_srtp_negotiation_result.mki_len > 0 )
+            {
+                mbedtls_printf( "    DTLS-SRTP mki value: " );
+                for( j = 0; j < dtls_srtp_negotiation_result.mki_len; j++ )
+                {
+                    mbedtls_printf( "%02X", dtls_srtp_negotiation_result.mki_value[j] );
+                }
+            }
+            else
+            {
+                mbedtls_printf( "    DTLS-SRTP no mki value negotiated" );
+            }
+            mbedtls_printf( "\n" );
+
+        }
+    }
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
+#endif /* MBEDTLS_SSL_EXPORT_KEYS */
 
 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
     ret = report_cid_usage( &ssl, "initial handshake" );
diff --git a/programs/test/query_config.c b/programs/test/query_config.c
index c35502f..1345b11 100644
--- a/programs/test/query_config.c
+++ b/programs/test/query_config.c
@@ -1480,6 +1480,14 @@
     }
 #endif /* MBEDTLS_SSL_DTLS_HELLO_VERIFY */
 
+#if defined(MBEDTLS_SSL_DTLS_SRTP)
+    if( strcmp( "MBEDTLS_SSL_DTLS_SRTP", config ) == 0 )
+    {
+        MACRO_EXPANSION_TO_STR( MBEDTLS_SSL_DTLS_SRTP );
+        return( 0 );
+    }
+#endif /* MBEDTLS_SSL_DTLS_SRTP */
+
 #if defined(MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE)
     if( strcmp( "MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE", config ) == 0 )
     {
diff --git a/tests/ssl-opt.sh b/tests/ssl-opt.sh
index 653d88d..59e7974 100755
--- a/tests/ssl-opt.sh
+++ b/tests/ssl-opt.sh
@@ -634,6 +634,23 @@
     fi
 }
 
+# Compare file content
+# Usage: find_in_both pattern file1 file2
+# extract from file1 the first line matching the pattern
+# check in file2 that the same line can be found
+find_in_both() {
+        srv_pattern=$(grep -m 1 "$1" "$2");
+        if [ -z "$srv_pattern" ]; then
+                return 1;
+        fi
+
+        if grep "$srv_pattern" $3 >/dev/null; then :
+                return 0;
+        else
+                return 1;
+        fi
+}
+
 # Usage: run_test name [-p proxy_cmd] srv_cmd cli_cmd cli_exit [option [...]]
 # Options:  -s pattern  pattern that must be present in server output
 #           -c pattern  pattern that must be present in client output
@@ -643,6 +660,7 @@
 #           -C pattern  pattern that must be absent in client output
 #           -U pattern  lines after pattern must be unique in server output
 #           -F call shell function on server output
+#           -g call shell function on server and client output
 run_test() {
     NAME="$1"
     shift 1
@@ -865,6 +883,12 @@
                     return
                 fi
                 ;;
+            "-g")
+                if ! eval "$2 '$SRV_OUT' '$CLI_OUT'"; then
+                    fail "function call to '$2' failed on Server and Client output"
+                    return
+                fi
+                ;;
 
             *)
                 echo "Unknown test: $1" >&2
@@ -8713,6 +8737,539 @@
             0 \
             -s "fragmenting handshake message"
 
+# Tests for DTLS-SRTP (RFC 5764)
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+run_test  "DTLS-SRTP all profiles supported" \
+          "$P_SRV dtls=1 use_srtp=1 debug_level=3" \
+          "$P_CLI dtls=1 use_srtp=1 debug_level=3" \
+          0 \
+          -s "found use_srtp extension" \
+          -s "found srtp profile" \
+          -s "selected srtp profile" \
+          -s "server hello, adding use_srtp extension" \
+          -s "DTLS-SRTP key material is"\
+          -c "client hello, adding use_srtp extension" \
+          -c "found use_srtp extension" \
+          -c "found srtp profile" \
+          -c "selected srtp profile" \
+          -c "DTLS-SRTP key material is"\
+          -g "find_in_both '^ *Keying material: [0-9A-F]*$'"\
+          -C "error"
+
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+run_test  "DTLS-SRTP server supports all profiles. Client supports one profile." \
+          "$P_SRV dtls=1 use_srtp=1 debug_level=3" \
+          "$P_CLI dtls=1 use_srtp=1 srtp_force_profile=5 debug_level=3" \
+          0 \
+          -s "found use_srtp extension" \
+          -s "found srtp profile: MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80" \
+          -s "selected srtp profile: MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80" \
+          -s "server hello, adding use_srtp extension" \
+          -s "DTLS-SRTP key material is"\
+          -c "client hello, adding use_srtp extension" \
+          -c "found use_srtp extension" \
+          -c "found srtp profile: MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80" \
+          -c "selected srtp profile" \
+          -c "DTLS-SRTP key material is"\
+          -g "find_in_both '^ *Keying material: [0-9A-F]*$'"\
+          -C "error"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+run_test  "DTLS-SRTP server supports one profile. Client supports all profiles." \
+          "$P_SRV dtls=1 use_srtp=1 srtp_force_profile=6 debug_level=3" \
+          "$P_CLI dtls=1 use_srtp=1 debug_level=3" \
+          0 \
+          -s "found use_srtp extension" \
+          -s "found srtp profile" \
+          -s "selected srtp profile: MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32" \
+          -s "server hello, adding use_srtp extension" \
+          -s "DTLS-SRTP key material is"\
+          -c "client hello, adding use_srtp extension" \
+          -c "found use_srtp extension" \
+          -c "found srtp profile: MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32" \
+          -c "selected srtp profile" \
+          -c "DTLS-SRTP key material is"\
+          -g "find_in_both '^ *Keying material: [0-9A-F]*$'"\
+          -C "error"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+run_test  "DTLS-SRTP server and Client support only one matching profile." \
+          "$P_SRV dtls=1 use_srtp=1 srtp_force_profile=2 debug_level=3" \
+          "$P_CLI dtls=1 use_srtp=1 srtp_force_profile=2 debug_level=3" \
+          0 \
+          -s "found use_srtp extension" \
+          -s "found srtp profile: MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32" \
+          -s "selected srtp profile: MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32" \
+          -s "server hello, adding use_srtp extension" \
+          -s "DTLS-SRTP key material is"\
+          -c "client hello, adding use_srtp extension" \
+          -c "found use_srtp extension" \
+          -c "found srtp profile: MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32" \
+          -c "selected srtp profile" \
+          -c "DTLS-SRTP key material is"\
+          -g "find_in_both '^ *Keying material: [0-9A-F]*$'"\
+          -C "error"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+run_test  "DTLS-SRTP server and Client support only one different profile." \
+          "$P_SRV dtls=1 use_srtp=1 srtp_force_profile=2 debug_level=3" \
+          "$P_CLI dtls=1 use_srtp=1 srtp_force_profile=6 debug_level=3" \
+          0 \
+          -s "found use_srtp extension" \
+          -s "found srtp profile: MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32" \
+          -S "selected srtp profile" \
+          -S "server hello, adding use_srtp extension" \
+          -S "DTLS-SRTP key material is"\
+          -c "client hello, adding use_srtp extension" \
+          -C "found use_srtp extension" \
+          -C "found srtp profile" \
+          -C "selected srtp profile" \
+          -C "DTLS-SRTP key material is"\
+          -C "error"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+run_test  "DTLS-SRTP server doesn't support use_srtp extension." \
+          "$P_SRV dtls=1 debug_level=3" \
+          "$P_CLI dtls=1 use_srtp=1 debug_level=3" \
+          0 \
+          -s "found use_srtp extension" \
+          -S "server hello, adding use_srtp extension" \
+          -S "DTLS-SRTP key material is"\
+          -c "client hello, adding use_srtp extension" \
+          -C "found use_srtp extension" \
+          -C "found srtp profile" \
+          -C "selected srtp profile" \
+          -C "DTLS-SRTP key material is"\
+          -C "error"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+run_test  "DTLS-SRTP all profiles supported. mki used" \
+          "$P_SRV dtls=1 use_srtp=1 support_mki=1 debug_level=3" \
+          "$P_CLI dtls=1 use_srtp=1 mki=542310ab34290481 debug_level=3" \
+          0 \
+          -s "found use_srtp extension" \
+          -s "found srtp profile" \
+          -s "selected srtp profile" \
+          -s "server hello, adding use_srtp extension" \
+          -s "dumping 'using mki' (8 bytes)" \
+          -s "DTLS-SRTP key material is"\
+          -c "client hello, adding use_srtp extension" \
+          -c "found use_srtp extension" \
+          -c "found srtp profile" \
+          -c "selected srtp profile" \
+          -c "dumping 'sending mki' (8 bytes)" \
+          -c "dumping 'received mki' (8 bytes)" \
+          -c "DTLS-SRTP key material is"\
+          -g "find_in_both '^ *Keying material: [0-9A-F]*$'"\
+          -g "find_in_both '^ *DTLS-SRTP mki value: [0-9A-F]*$'"\
+          -C "error"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+run_test  "DTLS-SRTP all profiles supported. server doesn't support mki." \
+          "$P_SRV dtls=1 use_srtp=1 debug_level=3" \
+          "$P_CLI dtls=1 use_srtp=1 mki=542310ab34290481 debug_level=3" \
+          0 \
+          -s "found use_srtp extension" \
+          -s "found srtp profile" \
+          -s "selected srtp profile" \
+          -s "server hello, adding use_srtp extension" \
+          -s "DTLS-SRTP key material is"\
+          -s "DTLS-SRTP no mki value negotiated"\
+          -S "dumping 'using mki' (8 bytes)" \
+          -c "client hello, adding use_srtp extension" \
+          -c "found use_srtp extension" \
+          -c "found srtp profile" \
+          -c "selected srtp profile" \
+          -c "DTLS-SRTP key material is"\
+          -c "DTLS-SRTP no mki value negotiated"\
+          -g "find_in_both '^ *Keying material: [0-9A-F]*$'"\
+          -c "dumping 'sending mki' (8 bytes)" \
+          -C "dumping 'received mki' (8 bytes)" \
+          -C "error"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+run_test  "DTLS-SRTP all profiles supported. openssl client." \
+          "$P_SRV dtls=1 use_srtp=1 debug_level=3" \
+          "$O_CLI -dtls1 -use_srtp SRTP_AES128_CM_SHA1_80:SRTP_AES128_CM_SHA1_32 -keymatexport 'EXTRACTOR-dtls_srtp' -keymatexportlen 60" \
+          0 \
+          -s "found use_srtp extension" \
+          -s "found srtp profile" \
+          -s "selected srtp profile" \
+          -s "server hello, adding use_srtp extension" \
+          -s "DTLS-SRTP key material is"\
+          -g "find_in_both '^ *Keying material: [0-9A-F]*$'"\
+          -c "SRTP Extension negotiated, profile=SRTP_AES128_CM_SHA1_80"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+run_test  "DTLS-SRTP server supports all profiles. Client supports all profiles, in different order. openssl client." \
+          "$P_SRV dtls=1 use_srtp=1 debug_level=3" \
+          "$O_CLI -dtls1 -use_srtp SRTP_AES128_CM_SHA1_32:SRTP_AES128_CM_SHA1_80 -keymatexport 'EXTRACTOR-dtls_srtp' -keymatexportlen 60" \
+          0 \
+          -s "found use_srtp extension" \
+          -s "found srtp profile" \
+          -s "selected srtp profile" \
+          -s "server hello, adding use_srtp extension" \
+          -s "DTLS-SRTP key material is"\
+          -g "find_in_both '^ *Keying material: [0-9A-F]*$'"\
+          -c "SRTP Extension negotiated, profile=SRTP_AES128_CM_SHA1_32"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+run_test  "DTLS-SRTP server supports all profiles. Client supports one profile. openssl client." \
+          "$P_SRV dtls=1 use_srtp=1 debug_level=3" \
+          "$O_CLI -dtls1 -use_srtp SRTP_AES128_CM_SHA1_32 -keymatexport 'EXTRACTOR-dtls_srtp' -keymatexportlen 60" \
+          0 \
+          -s "found use_srtp extension" \
+          -s "found srtp profile" \
+          -s "selected srtp profile" \
+          -s "server hello, adding use_srtp extension" \
+          -s "DTLS-SRTP key material is"\
+          -g "find_in_both '^ *Keying material: [0-9A-F]*$'"\
+          -c "SRTP Extension negotiated, profile=SRTP_AES128_CM_SHA1_32"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+run_test  "DTLS-SRTP server supports one profile. Client supports all profiles. openssl client." \
+          "$P_SRV dtls=1 use_srtp=1 srtp_force_profile=2 debug_level=3" \
+          "$O_CLI -dtls1 -use_srtp SRTP_AES128_CM_SHA1_80:SRTP_AES128_CM_SHA1_32 -keymatexport 'EXTRACTOR-dtls_srtp' -keymatexportlen 60" \
+          0 \
+          -s "found use_srtp extension" \
+          -s "found srtp profile" \
+          -s "selected srtp profile" \
+          -s "server hello, adding use_srtp extension" \
+          -s "DTLS-SRTP key material is"\
+          -g "find_in_both '^ *Keying material: [0-9A-F]*$'"\
+          -c "SRTP Extension negotiated, profile=SRTP_AES128_CM_SHA1_32"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+run_test  "DTLS-SRTP server and Client support only one matching profile. openssl client." \
+          "$P_SRV dtls=1 use_srtp=1 srtp_force_profile=2 debug_level=3" \
+          "$O_CLI -dtls1 -use_srtp SRTP_AES128_CM_SHA1_32 -keymatexport 'EXTRACTOR-dtls_srtp' -keymatexportlen 60" \
+          0 \
+          -s "found use_srtp extension" \
+          -s "found srtp profile" \
+          -s "selected srtp profile" \
+          -s "server hello, adding use_srtp extension" \
+          -s "DTLS-SRTP key material is"\
+          -g "find_in_both '^ *Keying material: [0-9A-F]*$'"\
+          -c "SRTP Extension negotiated, profile=SRTP_AES128_CM_SHA1_32"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+run_test  "DTLS-SRTP server and Client support only one different profile. openssl client." \
+          "$P_SRV dtls=1 use_srtp=1 srtp_force_profile=1 debug_level=3" \
+          "$O_CLI -dtls1 -use_srtp SRTP_AES128_CM_SHA1_32 -keymatexport 'EXTRACTOR-dtls_srtp' -keymatexportlen 60" \
+          0 \
+          -s "found use_srtp extension" \
+          -s "found srtp profile" \
+          -S "selected srtp profile" \
+          -S "server hello, adding use_srtp extension" \
+          -S "DTLS-SRTP key material is"\
+          -C "SRTP Extension negotiated, profile"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+run_test  "DTLS-SRTP server doesn't support use_srtp extension. openssl client" \
+          "$P_SRV dtls=1 debug_level=3" \
+          "$O_CLI -dtls1 -use_srtp SRTP_AES128_CM_SHA1_80:SRTP_AES128_CM_SHA1_32 -keymatexport 'EXTRACTOR-dtls_srtp' -keymatexportlen 60" \
+          0 \
+          -s "found use_srtp extension" \
+          -S "server hello, adding use_srtp extension" \
+          -S "DTLS-SRTP key material is"\
+          -C "SRTP Extension negotiated, profile"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+run_test  "DTLS-SRTP all profiles supported. openssl server" \
+          "$O_SRV -dtls1 -verify 0 -use_srtp SRTP_AES128_CM_SHA1_80:SRTP_AES128_CM_SHA1_32 -keymatexport 'EXTRACTOR-dtls_srtp' -keymatexportlen 60" \
+          "$P_CLI dtls=1 use_srtp=1 debug_level=3" \
+          0 \
+          -c "client hello, adding use_srtp extension" \
+          -c "found use_srtp extension" \
+          -c "found srtp profile" \
+          -c "selected srtp profile: MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80" \
+          -c "DTLS-SRTP key material is"\
+          -C "error"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+run_test  "DTLS-SRTP server supports all profiles. Client supports all profiles, in different order. openssl server." \
+          "$O_SRV -dtls1 -verify 0 -use_srtp SRTP_AES128_CM_SHA1_32:SRTP_AES128_CM_SHA1_80 -keymatexport 'EXTRACTOR-dtls_srtp' -keymatexportlen 60" \
+          "$P_CLI dtls=1 use_srtp=1 debug_level=3" \
+          0 \
+          -c "client hello, adding use_srtp extension" \
+          -c "found use_srtp extension" \
+          -c "found srtp profile" \
+          -c "selected srtp profile" \
+          -c "DTLS-SRTP key material is"\
+          -C "error"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+run_test  "DTLS-SRTP server supports all profiles. Client supports one profile. openssl server." \
+          "$O_SRV -dtls1 -verify 0 -use_srtp SRTP_AES128_CM_SHA1_80:SRTP_AES128_CM_SHA1_32 -keymatexport 'EXTRACTOR-dtls_srtp' -keymatexportlen 60" \
+          "$P_CLI dtls=1 use_srtp=1 srtp_force_profile=2 debug_level=3" \
+          0 \
+          -c "client hello, adding use_srtp extension" \
+          -c "found use_srtp extension" \
+          -c "found srtp profile: MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32" \
+          -c "selected srtp profile" \
+          -c "DTLS-SRTP key material is"\
+          -C "error"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+run_test  "DTLS-SRTP server supports one profile. Client supports all profiles. openssl server." \
+          "$O_SRV -dtls1 -verify 0 -use_srtp SRTP_AES128_CM_SHA1_32 -keymatexport 'EXTRACTOR-dtls_srtp' -keymatexportlen 60" \
+          "$P_CLI dtls=1 use_srtp=1 debug_level=3" \
+          0 \
+          -c "client hello, adding use_srtp extension" \
+          -c "found use_srtp extension" \
+          -c "found srtp profile: MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32" \
+          -c "selected srtp profile" \
+          -c "DTLS-SRTP key material is"\
+          -C "error"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+run_test  "DTLS-SRTP server and Client support only one matching profile. openssl server." \
+          "$O_SRV -dtls1 -verify 0 -use_srtp SRTP_AES128_CM_SHA1_32 -keymatexport 'EXTRACTOR-dtls_srtp' -keymatexportlen 60" \
+          "$P_CLI dtls=1 use_srtp=1 srtp_force_profile=2 debug_level=3" \
+          0 \
+          -c "client hello, adding use_srtp extension" \
+          -c "found use_srtp extension" \
+          -c "found srtp profile: MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32" \
+          -c "selected srtp profile" \
+          -c "DTLS-SRTP key material is"\
+          -C "error"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+run_test  "DTLS-SRTP server and Client support only one different profile. openssl server." \
+          "$O_SRV -dtls1 -verify 0 -use_srtp SRTP_AES128_CM_SHA1_32 -keymatexport 'EXTRACTOR-dtls_srtp' -keymatexportlen 60" \
+          "$P_CLI dtls=1 use_srtp=1 srtp_force_profile=6 debug_level=3" \
+          0 \
+          -c "client hello, adding use_srtp extension" \
+          -C "found use_srtp extension" \
+          -C "found srtp profile" \
+          -C "selected srtp profile" \
+          -C "DTLS-SRTP key material is"\
+          -C "error"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+run_test  "DTLS-SRTP server doesn't support use_srtp extension. openssl server" \
+          "$O_SRV -dtls1" \
+          "$P_CLI dtls=1 use_srtp=1 debug_level=3" \
+          0 \
+          -c "client hello, adding use_srtp extension" \
+          -C "found use_srtp extension" \
+          -C "found srtp profile" \
+          -C "selected srtp profile" \
+          -C "DTLS-SRTP key material is"\
+          -C "error"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+run_test  "DTLS-SRTP all profiles supported. server doesn't support mki. openssl server." \
+          "$O_SRV -dtls1 -verify 0 -use_srtp SRTP_AES128_CM_SHA1_80:SRTP_AES128_CM_SHA1_32 -keymatexport 'EXTRACTOR-dtls_srtp' -keymatexportlen 60" \
+          "$P_CLI dtls=1 use_srtp=1 mki=542310ab34290481 debug_level=3" \
+          0 \
+          -c "client hello, adding use_srtp extension" \
+          -c "found use_srtp extension" \
+          -c "found srtp profile" \
+          -c "selected srtp profile" \
+          -c "DTLS-SRTP key material is"\
+          -c "DTLS-SRTP no mki value negotiated"\
+          -c "dumping 'sending mki' (8 bytes)" \
+          -C "dumping 'received mki' (8 bytes)" \
+          -C "error"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+requires_gnutls
+run_test  "DTLS-SRTP all profiles supported. gnutls client." \
+          "$P_SRV dtls=1 use_srtp=1 debug_level=3" \
+          "$G_CLI -u --srtp-profiles=SRTP_AES128_CM_HMAC_SHA1_80:SRTP_AES128_CM_HMAC_SHA1_32:SRTP_NULL_HMAC_SHA1_80:SRTP_NULL_SHA1_32 --insecure 127.0.0.1" \
+          0 \
+          -s "found use_srtp extension" \
+          -s "found srtp profile" \
+          -s "selected srtp profile" \
+          -s "server hello, adding use_srtp extension" \
+          -s "DTLS-SRTP key material is"\
+          -c "SRTP profile: SRTP_AES128_CM_HMAC_SHA1_80"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+requires_gnutls
+run_test  "DTLS-SRTP server supports all profiles. Client supports all profiles, in different order. gnutls client." \
+          "$P_SRV dtls=1 use_srtp=1 debug_level=3" \
+          "$G_CLI -u --srtp-profiles=SRTP_NULL_HMAC_SHA1_80:SRTP_AES128_CM_HMAC_SHA1_80:SRTP_NULL_SHA1_32:SRTP_AES128_CM_HMAC_SHA1_32 --insecure 127.0.0.1" \
+          0 \
+          -s "found use_srtp extension" \
+          -s "found srtp profile" \
+          -s "selected srtp profile" \
+          -s "server hello, adding use_srtp extension" \
+          -s "DTLS-SRTP key material is"\
+          -c "SRTP profile: SRTP_NULL_HMAC_SHA1_80"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+requires_gnutls
+run_test  "DTLS-SRTP server supports all profiles. Client supports one profile. gnutls client." \
+          "$P_SRV dtls=1 use_srtp=1 debug_level=3" \
+          "$G_CLI -u --srtp-profiles=SRTP_AES128_CM_HMAC_SHA1_32 --insecure 127.0.0.1" \
+          0 \
+          -s "found use_srtp extension" \
+          -s "found srtp profile: MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32" \
+          -s "selected srtp profile: MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32" \
+          -s "server hello, adding use_srtp extension" \
+          -s "DTLS-SRTP key material is"\
+          -c "SRTP profile: SRTP_AES128_CM_HMAC_SHA1_32"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+requires_gnutls
+run_test  "DTLS-SRTP server supports one profile. Client supports all profiles. gnutls client." \
+          "$P_SRV dtls=1 use_srtp=1 srtp_force_profile=6 debug_level=3" \
+          "$G_CLI -u --srtp-profiles=SRTP_AES128_CM_HMAC_SHA1_80:SRTP_AES128_CM_HMAC_SHA1_32:SRTP_NULL_HMAC_SHA1_80:SRTP_NULL_SHA1_32 --insecure 127.0.0.1" \
+          0 \
+          -s "found use_srtp extension" \
+          -s "found srtp profile" \
+          -s "selected srtp profile: MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_32" \
+          -s "server hello, adding use_srtp extension" \
+          -s "DTLS-SRTP key material is"\
+          -c "SRTP profile: SRTP_NULL_SHA1_32"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+requires_gnutls
+run_test  "DTLS-SRTP server and Client support only one matching profile. gnutls client." \
+          "$P_SRV dtls=1 use_srtp=1 srtp_force_profile=2 debug_level=3" \
+          "$G_CLI -u --srtp-profiles=SRTP_AES128_CM_HMAC_SHA1_32 --insecure 127.0.0.1" \
+          0 \
+          -s "found use_srtp extension" \
+          -s "found srtp profile" \
+          -s "selected srtp profile" \
+          -s "server hello, adding use_srtp extension" \
+          -s "DTLS-SRTP key material is"\
+          -c "SRTP profile: SRTP_AES128_CM_HMAC_SHA1_32"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+requires_gnutls
+run_test  "DTLS-SRTP server and Client support only one different profile. gnutls client." \
+          "$P_SRV dtls=1 use_srtp=1 srtp_force_profile=1 debug_level=3" \
+          "$G_CLI -u --srtp-profiles=SRTP_AES128_CM_HMAC_SHA1_32 --insecure 127.0.0.1" \
+          0 \
+          -s "found use_srtp extension" \
+          -s "found srtp profile" \
+          -S "selected srtp profile" \
+          -S "server hello, adding use_srtp extension" \
+          -S "DTLS-SRTP key material is"\
+          -C "SRTP profile:"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+requires_gnutls
+run_test  "DTLS-SRTP server doesn't support use_srtp extension. gnutls client" \
+          "$P_SRV dtls=1 debug_level=3" \
+          "$G_CLI -u --srtp-profiles=SRTP_AES128_CM_HMAC_SHA1_80:SRTP_AES128_CM_HMAC_SHA1_32:SRTP_NULL_HMAC_SHA1_80:SRTP_NULL_SHA1_32 --insecure 127.0.0.1" \
+          0 \
+          -s "found use_srtp extension" \
+          -S "server hello, adding use_srtp extension" \
+          -S "DTLS-SRTP key material is"\
+          -C "SRTP profile:"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+requires_gnutls
+run_test  "DTLS-SRTP all profiles supported. gnutls server" \
+          "$G_SRV -u --srtp-profiles=SRTP_AES128_CM_HMAC_SHA1_80:SRTP_AES128_CM_HMAC_SHA1_32:SRTP_NULL_HMAC_SHA1_80:SRTP_NULL_SHA1_32" \
+          "$P_CLI dtls=1 use_srtp=1 debug_level=3" \
+          0 \
+          -c "client hello, adding use_srtp extension" \
+          -c "found use_srtp extension" \
+          -c "found srtp profile" \
+          -c "selected srtp profile: MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80" \
+          -c "DTLS-SRTP key material is"\
+          -C "error"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+requires_gnutls
+run_test  "DTLS-SRTP server supports all profiles. Client supports all profiles, in different order. gnutls server." \
+          "$G_SRV -u --srtp-profiles=SRTP_NULL_SHA1_32:SRTP_AES128_CM_HMAC_SHA1_32:SRTP_AES128_CM_HMAC_SHA1_80:SRTP_NULL_HMAC_SHA1_80:SRTP_NULL_SHA1_32" \
+          "$P_CLI dtls=1 use_srtp=1 debug_level=3" \
+          0 \
+          -c "client hello, adding use_srtp extension" \
+          -c "found use_srtp extension" \
+          -c "found srtp profile" \
+          -c "selected srtp profile: MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_80" \
+          -c "DTLS-SRTP key material is"\
+          -C "error"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+requires_gnutls
+run_test  "DTLS-SRTP server supports all profiles. Client supports one profile. gnutls server." \
+          "$G_SRV -u --srtp-profiles=SRTP_NULL_SHA1_32:SRTP_AES128_CM_HMAC_SHA1_32:SRTP_AES128_CM_HMAC_SHA1_80:SRTP_NULL_HMAC_SHA1_80:SRTP_NULL_SHA1_32" \
+          "$P_CLI dtls=1 use_srtp=1 srtp_force_profile=2 debug_level=3" \
+          0 \
+          -c "client hello, adding use_srtp extension" \
+          -c "found use_srtp extension" \
+          -c "found srtp profile: MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32" \
+          -c "selected srtp profile" \
+          -c "DTLS-SRTP key material is"\
+          -C "error"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+requires_gnutls
+run_test  "DTLS-SRTP server supports one profile. Client supports all profiles. gnutls server." \
+          "$G_SRV -u --srtp-profiles=SRTP_NULL_HMAC_SHA1_80" \
+          "$P_CLI dtls=1 use_srtp=1 debug_level=3" \
+          0 \
+          -c "client hello, adding use_srtp extension" \
+          -c "found use_srtp extension" \
+          -c "found srtp profile: MBEDTLS_TLS_SRTP_NULL_HMAC_SHA1_80" \
+          -c "selected srtp profile" \
+          -c "DTLS-SRTP key material is"\
+          -C "error"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+requires_gnutls
+run_test  "DTLS-SRTP server and Client support only one matching profile. gnutls server." \
+          "$G_SRV -u --srtp-profiles=SRTP_AES128_CM_HMAC_SHA1_32" \
+          "$P_CLI dtls=1 use_srtp=1 srtp_force_profile=2 debug_level=3" \
+          0 \
+          -c "client hello, adding use_srtp extension" \
+          -c "found use_srtp extension" \
+          -c "found srtp profile: MBEDTLS_TLS_SRTP_AES128_CM_HMAC_SHA1_32" \
+          -c "selected srtp profile" \
+          -c "DTLS-SRTP key material is"\
+          -C "error"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+requires_gnutls
+run_test  "DTLS-SRTP server and Client support only one different profile. gnutls server." \
+          "$G_SRV -u --srtp-profiles=SRTP_AES128_CM_HMAC_SHA1_32" \
+          "$P_CLI dtls=1 use_srtp=1 srtp_force_profile=6 debug_level=3" \
+          0 \
+          -c "client hello, adding use_srtp extension" \
+          -C "found use_srtp extension" \
+          -C "found srtp profile" \
+          -C "selected srtp profile" \
+          -C "DTLS-SRTP key material is"\
+          -C "error"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+requires_gnutls
+run_test  "DTLS-SRTP server doesn't support use_srtp extension. gnutls server" \
+          "$G_SRV -u" \
+          "$P_CLI dtls=1 use_srtp=1 debug_level=3" \
+          0 \
+          -c "client hello, adding use_srtp extension" \
+          -C "found use_srtp extension" \
+          -C "found srtp profile" \
+          -C "selected srtp profile" \
+          -C "DTLS-SRTP key material is"\
+          -C "error"
+
+requires_config_enabled MBEDTLS_SSL_DTLS_SRTP
+requires_gnutls
+run_test  "DTLS-SRTP all profiles supported. mki used. gnutls server." \
+          "$G_SRV -u --srtp-profiles=SRTP_AES128_CM_HMAC_SHA1_80:SRTP_AES128_CM_HMAC_SHA1_32:SRTP_NULL_HMAC_SHA1_80:SRTP_NULL_SHA1_32" \
+          "$P_CLI dtls=1 use_srtp=1 mki=542310ab34290481 debug_level=3" \
+          0 \
+          -c "client hello, adding use_srtp extension" \
+          -c "found use_srtp extension" \
+          -c "found srtp profile" \
+          -c "selected srtp profile" \
+          -c "DTLS-SRTP key material is"\
+          -c "DTLS-SRTP mki value:"\
+          -c "dumping 'sending mki' (8 bytes)" \
+          -c "dumping 'received mki' (8 bytes)" \
+          -C "error"
+
 # Tests for specific things with "unreliable" UDP connection
 
 not_with_valgrind # spurious resend due to timeout