diff --git a/tls.go b/tls.go
index 562fb62..49781f7 100644
--- a/tls.go
+++ b/tls.go
@@ -14,18 +14,25 @@ import (
 	"unsafe"
 )
 
+const (
+	GNUTLS_NAME_DNS     = 1
+	GNUTLS_X509_FMT_PEM = 1
+)
+
 // Conn tls connection for client
 type Conn struct {
 	c         net.Conn
 	sess      *C.struct_session
 	handshake bool
+	cservname *C.char
 }
 
 // Config tls configure
 type Config struct {
-	ServerName string
-	CrtFile    string
-	KeyFile    string
+	ServerName         string
+	CrtFile            string
+	KeyFile            string
+	InsecureSkipVerify bool
 }
 type listener struct {
 	l net.Listener
@@ -93,7 +100,8 @@ func NewServerConn(c net.Conn, cfg *Config) (*Conn, error) {
 	keyfile := C.CString(cfg.KeyFile)
 	defer C.free(unsafe.Pointer(crtfile))
 	defer C.free(unsafe.Pointer(keyfile))
-	ret := C.set_keyfile(sess, crtfile, keyfile)
+	ret := C.gnutls_certificate_set_x509_key_file(
+		sess.xcred, crtfile, keyfile, GNUTLS_X509_FMT_PEM)
 	if int(ret) < 0 {
 		cerrstr := C.gnutls_strerror(ret)
 		return nil, fmt.Errorf("set keyfile failed: %s", C.GoString(cerrstr))
@@ -112,8 +120,10 @@ func NewClientConn(c net.Conn, cfg *Config) (*Conn, error) {
 	if cfg != nil {
 		if cfg.ServerName != "" {
 			srvname := C.CString(cfg.ServerName)
-			defer C.free(unsafe.Pointer(srvname))
-			C.set_servername(sess, srvname, C.int(len(cfg.ServerName)))
+			//defer C.free(unsafe.Pointer(srvname))
+			conn.cservname = srvname
+			C.gnutls_server_name_set(sess.session, GNUTLS_NAME_DNS,
+				unsafe.Pointer(srvname), C.size_t(len(cfg.ServerName)))
 		}
 
 		if cfg.CrtFile != "" && cfg.KeyFile != "" {
@@ -121,11 +131,22 @@ func NewClientConn(c net.Conn, cfg *Config) (*Conn, error) {
 			keyfile := C.CString(cfg.KeyFile)
 			defer C.free(unsafe.Pointer(crtfile))
 			defer C.free(unsafe.Pointer(keyfile))
-			ret := C.set_keyfile(sess, crtfile, keyfile)
+			ret := C.gnutls_certificate_set_x509_key_file(
+				sess.xcred, crtfile, keyfile, GNUTLS_X509_FMT_PEM)
 			if int(ret) < 0 {
-				return nil, fmt.Errorf("set keyfile failed: %s", C.GoString(C.gnutls_strerror(ret)))
+				return nil, fmt.Errorf("set keyfile failed: %s",
+					C.GoString(C.gnutls_strerror(ret)))
 			}
 		}
+		if !cfg.InsecureSkipVerify {
+			if conn.cservname != nil {
+				C.gnutls_session_set_verify_cert(sess.session, conn.cservname, 0)
+			} else {
+				C.gnutls_session_set_verify_cert(sess.session, nil, 0)
+			}
+		}
+	} else {
+		C.gnutls_session_set_verify_cert(sess.session, nil, 0)
 	}
 	return conn, nil
 }
@@ -144,7 +165,7 @@ func (c *Conn) Handshake() error {
 	return nil
 }
 
-// Read
+// Read read data from tls connection
 func (c *Conn) Read(buf []byte) (n int, err error) {
 	if !c.handshake {
 		err = c.Handshake()
@@ -158,9 +179,10 @@ func (c *Conn) Read(buf []byte) (n int, err error) {
 	cbuf := C.malloc(C.size_t(bufLen))
 	defer C.free(cbuf)
 
-	ret := C.read_application_data(c.sess, (*C.char)(cbuf), C.int(bufLen))
+	ret := C.gnutls_record_recv(c.sess.session, cbuf, C.size_t(bufLen))
 	if int(ret) < 0 {
-		return 0, fmt.Errorf("read error: %s", C.GoString(C.gnutls_strerror(ret)))
+		return 0, fmt.Errorf("read error: %s",
+			C.GoString(C.gnutls_strerror(C.int(ret))))
 	}
 
 	if int(ret) == 0 {
@@ -168,12 +190,12 @@ func (c *Conn) Read(buf []byte) (n int, err error) {
 	}
 
 	n = int(ret)
-	gobuf2 := C.GoBytes(cbuf, ret)
+	gobuf2 := C.GoBytes(cbuf, C.int(ret))
 	copy(buf, gobuf2)
 	return n, nil
 }
 
-// Write
+// Write write data to tls connection
 func (c *Conn) Write(buf []byte) (n int, err error) {
 	if !c.handshake {
 		err = c.Handshake()
@@ -185,11 +207,12 @@ func (c *Conn) Write(buf []byte) (n int, err error) {
 	cbuf := C.CBytes(buf)
 	defer C.free(cbuf)
 
-	ret := C.write_application_data(c.sess, (*C.char)(cbuf), C.int(len(buf)))
+	ret := C.gnutls_record_send(c.sess.session, cbuf, C.size_t(len(buf)))
 	n = int(ret)
 
 	if n < 0 {
-		return 0, fmt.Errorf("write error: %s", C.GoString(C.gnutls_strerror(ret)))
+		return 0, fmt.Errorf("write error: %s",
+			C.GoString(C.gnutls_strerror(C.int(ret))))
 	}
 
 	if int(ret) == 0 {
@@ -199,10 +222,13 @@ func (c *Conn) Write(buf []byte) (n int, err error) {
 	return n, nil
 }
 
-// Close close the conn
+// Close close the conn and destroy the tls context
 func (c *Conn) Close() error {
 	C.session_destroy(c.sess)
 	c.c.Close()
+	if c.cservname != nil {
+		C.free(unsafe.Pointer(c.cservname))
+	}
 	return nil
 }