Add client finished

Signed-off-by: Jerry Yu <jerry.h.yu@arm.com>
diff --git a/library/ssl_tls13_generic.c b/library/ssl_tls13_generic.c
index f5e38ab..b687ad1 100644
--- a/library/ssl_tls13_generic.c
+++ b/library/ssl_tls13_generic.c
@@ -1182,6 +1182,23 @@
 static int ssl_tls13_postprocess_finished_message( mbedtls_ssl_context *ssl )
 {
 
+#if defined(MBEDTLS_SSL_SRV_C)
+    int ret;
+    if( ssl->conf->endpoint == MBEDTLS_SSL_IS_SERVER )
+    {
+        /* Compute resumption_master_secret */
+        ret = mbedtls_ssl_tls13_generate_resumption_master_secret( ssl );
+        if( ret != 0 )
+        {
+            MBEDTLS_SSL_DEBUG_RET( 1,
+               "mbedtls_ssl_tls13_generate_resumption_master_secret ", ret );
+            return( ret );
+        }
+
+        return( 0 );
+    }
+#endif /* MBEDTLS_SSL_SRV_C */
+
 #if defined(MBEDTLS_SSL_CLI_C)
     if( ssl->conf->endpoint == MBEDTLS_SSL_IS_CLIENT )
     {
diff --git a/library/ssl_tls13_keys.c b/library/ssl_tls13_keys.c
index 072c869..3e62617 100644
--- a/library/ssl_tls13_keys.c
+++ b/library/ssl_tls13_keys.c
@@ -1565,4 +1565,13 @@
     return( ret );
 }
 
+int mbedtls_ssl_tls13_generate_resumption_master_secret(
+    mbedtls_ssl_context *ssl )
+{
+    /* Erase master secrets */
+    mbedtls_platform_zeroize( &ssl->handshake->tls13_master_secrets,
+                              sizeof( ssl->handshake->tls13_master_secrets ) );
+    return( 0 );
+}
+
 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
diff --git a/library/ssl_tls13_keys.h b/library/ssl_tls13_keys.h
index 676ebae..479bb4e 100644
--- a/library/ssl_tls13_keys.h
+++ b/library/ssl_tls13_keys.h
@@ -611,6 +611,19 @@
     mbedtls_ssl_context* ssl, mbedtls_ssl_key_set *traffic_keys );
 
 /**
+ * \brief Compute TLS 1.3 resumption master secret.
+ *
+ * \param ssl  The SSL context to operate on. This must be in
+ *             key schedule stage \c Application, see
+ *             mbedtls_ssl_tls13_key_schedule_stage_application().
+ *
+ * \returns    \c 0 on success.
+ * \returns    A negative error code on failure.
+ */
+int mbedtls_ssl_tls13_generate_resumption_master_secret(
+    mbedtls_ssl_context* ssl );
+
+/**
  * \brief Calculate the verify_data value for the client or server TLS 1.3
  * Finished message.
  *
diff --git a/library/ssl_tls13_server.c b/library/ssl_tls13_server.c
index c9d7ece..df3221d 100644
--- a/library/ssl_tls13_server.c
+++ b/library/ssl_tls13_server.c
@@ -1496,8 +1496,17 @@
  */
 int ssl_tls13_process_client_finished( mbedtls_ssl_context *ssl )
 {
-    ((void) ssl);
-    return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE );
+    int ret;
+    MBEDTLS_SSL_DEBUG_MSG( 1,
+                  ( "Switch to handshake traffic keys for outbound traffic" ) );
+    mbedtls_ssl_set_inbound_transform( ssl, ssl->handshake->transform_handshake );
+    ret = mbedtls_ssl_tls13_process_finished_message( ssl );
+    if( ret != 0 )
+        return( ret );
+
+    mbedtls_ssl_handshake_set_state( ssl, MBEDTLS_SSL_FLUSH_BUFFERS );
+    return( 0 );
+
 }
 
 /*