diff --git a/cstp.c b/cstp.c
index ba2f01a5..2f4799b4 100644
--- a/cstp.c
+++ b/cstp.c
@@ -576,7 +576,7 @@ static int start_cstp_connection(struct openconnect_info *vpninfo)
 }
 
 
-int openconnect_make_cstp_connection(struct openconnect_info *vpninfo)
+int cstp_connect(struct openconnect_info *vpninfo)
 {
 	int ret;
 	int deflate_bufsize = 0;
diff --git a/library.c b/library.c
index d885d75d..6fbfc4c0 100644
--- a/library.c
+++ b/library.c
@@ -92,6 +92,8 @@ struct openconnect_info *openconnect_vpninfo_new(const char *useragent,
 #endif
 
 	vpninfo->proto.vpn_close_session = cstp_bye;
+	vpninfo->proto.tcp_connect = cstp_connect;
+	vpninfo->proto.tcp_mainloop = cstp_mainloop;
 #ifdef HAVE_DTLS
 	vpninfo->proto.udp_setup = dtls_setup;
 	vpninfo->proto.udp_mainloop = dtls_mainloop;
@@ -122,6 +124,11 @@ int openconnect_setup_dtls(struct openconnect_info *vpninfo,
 	return -EINVAL;
 }
 
+int openconnect_make_cstp_connection(struct openconnect_info *vpninfo)
+{
+	return vpninfo->proto.tcp_connect(vpninfo);
+}
+
 int openconnect_set_reported_os(struct openconnect_info *vpninfo,
 				const char *os)
 {
diff --git a/mainloop.c b/mainloop.c
index 43ccaff4..4f0a4ba7 100644
--- a/mainloop.c
+++ b/mainloop.c
@@ -145,7 +145,7 @@ int openconnect_mainloop(struct openconnect_info *vpninfo,
 			did_work += ret;
 		}
 
-		ret = cstp_mainloop(vpninfo, &timeout);
+		ret = vpninfo->proto.tcp_mainloop(vpninfo, &timeout);
 		if (vpninfo->quit_reason)
 			break;
 		did_work += ret;
diff --git a/openconnect-internal.h b/openconnect-internal.h
index 807d0672..8b54b326 100644
--- a/openconnect-internal.h
+++ b/openconnect-internal.h
@@ -205,6 +205,11 @@ struct proxy_auth_state {
 struct vpn_proto {
 	int (*vpn_close_session)(struct openconnect_info *vpninfo, const char *reason);
 
+	/* Establish the TCP connection (and obtain configuration) */
+	int (*tcp_connect)(struct openconnect_info *vpninfo);
+
+	int (*tcp_mainloop)(struct openconnect_info *vpninfo, int *timeout);
+
 	/* Set up the UDP (DTLS) connection. Doesn't actually *start* it. */
 	int (*udp_setup)(struct openconnect_info *vpninfo, int attempt_period);
 
@@ -656,6 +661,7 @@ void dtls_close(struct openconnect_info *vpninfo);
 void dtls_shutdown(struct openconnect_info *vpninfo);
 
 /* cstp.c */
+int cstp_connect(struct openconnect_info *vpninfo);
 int cstp_mainloop(struct openconnect_info *vpninfo, int *timeout);
 int cstp_bye(struct openconnect_info *vpninfo, const char *reason);
 void cstp_free_splits(struct openconnect_info *vpninfo);