tsilo: add check for empty aor

Fix: #1775
(cherry picked from commit 5a5d742eb459249995114eb6a3642f99c6770496)
(cherry picked from commit 23a5c07e924a2feb5f09b727f4ad0faf6c5af349)
(cherry picked from commit f9e7ea0a35d4115f2437d285a8e27aceaf74a5fd)

src/modules/tsilo/ts_store.c

@@ -71,6 +71,11 @@ int ts_store(struct sip_msg* msg, str *puri) {
 	else
 		aor = ruri.user;
 
+	if(aor.s==NULL) {
+		LM_ERR("malformed aor from uri[%.*s]\n", suri.len, suri.s);
+		return -1;
+	}
+
 	t = _tmb.t_gett();
 	if (!t || t==T_UNDEFINED) {
 		LM_ERR("no transaction defined for %.*s\n", aor.len, aor.s);