diff --git a/include/osmocom/gsm/ipa.h b/include/osmocom/gsm/ipa.h
index 1227ee1..0bb01c5 100644
--- a/include/osmocom/gsm/ipa.h
+++ b/include/osmocom/gsm/ipa.h
@@ -27,6 +27,9 @@
 /* parse a buffer of ID tags into a osmocom TLV style representation */
 int ipa_ccm_idtag_parse(struct tlv_parsed *dec, unsigned char *buf, int len);
 
+/* Is the TAG included in the length field? */
+int ipa_ccm_idtag_parse_off(struct tlv_parsed *dec, unsigned char *buf, int len, const int len_offset);
+
 /* parse an Unit ID in string format into the 'ipaccess_unit' data structure */
 int ipa_parse_unitid(const char *str, struct ipaccess_unit *unit_data);