mac80211: export IE splitting function

Export ieee80211_ie_split function, so it can be reused by
drivers which need to insert additional elements.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 28 insertions, 0 deletions

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 9dc5e7606322..96d224357c8c 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -4906,4 +4906,32 @@ void ieee80211_update_p2p_noa(struct ieee80211_noa_data *data, u32 tsf);
 void ieee80211_tdls_oper_request(struct ieee80211_vif *vif, const u8 *peer,
                                  enum nl80211_tdls_operation oper,
                                  u16 reason_code, gfp_t gfp);
+
+/**
+ * ieee80211_ie_split - split an IE buffer according to ordering
+ *
+ * @ies: the IE buffer
+ * @ielen: the length of the IE buffer
+ * @ids: an array with element IDs that are allowed before
+ *      the split
+ * @n_ids: the size of the element ID array
+ * @offset: offset where to start splitting in the buffer
+ *
+ * This function splits an IE buffer by updating the @offset
+ * variable to point to the location where the buffer should be
+ * split.
+ *
+ * It assumes that the given IE buffer is well-formed, this
+ * has to be guaranteed by the caller!
+ *
+ * It also assumes that the IEs in the buffer are ordered
+ * correctly, if not the result of using this function will not
+ * be ordered correctly either, i.e. it does no reordering.
+ *
+ * The function returns the offset where the next part of the
+ * buffer starts, which may be @ielen if the entire (remainder)
+ * of the buffer should be used.
+ */
+size_t ieee80211_ie_split(const u8 *ies, size_t ielen,
+                          const u8 *ids, int n_ids, size_t offset);
 #endif /* MAC80211_H */