openconnect: add an option to support stoken

Add a new build configuration option for openconnect and let it link
against libstoken if instructed to. Two new uci configuration variables
are introduced: "token_mode" and "token_secret" to allow openconnect to
use those.

Signed-off-by: Florian Fainelli <florian@openwrt.org>

net/openconnect/files/openconnect.sh

@@ -17,7 +17,7 @@ proto_openconnect_init_config() {
 proto_openconnect_setup() {
 	local config="$1"
 
-	json_get_vars server port username serverhash authgroup password vgroup
+	json_get_vars server port username serverhash authgroup password vgroup token_mode token_secret
 
 	grep -q tun /proc/modules || insmod tun
 
@@ -57,6 +57,9 @@ proto_openconnect_setup() {
 		append cmdline "--passwd-on-stdin"
 	}
 
+	[ -n "$token_mode" ] && append cmdline "--token-mode=$token_mode"
+	[ -n "$token_secret" ] && append cmdline "--token-secret=$token_secret"
+
 	proto_export INTERFACE="$config"
 	logger -t openconnect "executing 'openconnect $cmdline'"