diff options
Diffstat (limited to 'include/linux/ieee80211.h')
-rw-r--r-- | include/linux/ieee80211.h | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/include/linux/ieee80211.h b/include/linux/ieee80211.h index a80516fd65c8..d3417c18ee2f 100644 --- a/include/linux/ieee80211.h +++ b/include/linux/ieee80211.h @@ -2630,4 +2630,57 @@ static inline bool ieee80211_action_contains_tpc(struct sk_buff *skb) return true; } +struct element { + u8 id; + u8 datalen; + u8 data[]; +} __packed; + +/* element iteration helpers */ +#define for_each_element(_elem, _data, _datalen) \ + for (_elem = (const struct element *)(_data); \ + (const u8 *)(_data) + (_datalen) - (const u8 *)_elem >= \ + (int)sizeof(*_elem) && \ + (const u8 *)(_data) + (_datalen) - (const u8 *)_elem >= \ + (int)sizeof(*_elem) + _elem->datalen; \ + _elem = (const struct element *)(_elem->data + _elem->datalen)) + +#define for_each_element_id(element, _id, data, datalen) \ + for_each_element(element, data, datalen) \ + if (element->id == (_id)) + +#define for_each_element_extid(element, extid, data, datalen) \ + for_each_element(element, data, datalen) \ + if (element->id == WLAN_EID_EXTENSION && \ + element->datalen > 0 && \ + element->data[0] == (extid)) + +#define for_each_subelement(sub, element) \ + for_each_element(sub, (element)->data, (element)->datalen) + +#define for_each_subelement_id(sub, id, element) \ + for_each_element_id(sub, id, (element)->data, (element)->datalen) + +#define for_each_subelement_extid(sub, extid, element) \ + for_each_element_extid(sub, extid, (element)->data, (element)->datalen) + +/** + * for_each_element_completed - determine if element parsing consumed all data + * @element: element pointer after for_each_element() or friends + * @data: same data pointer as passed to for_each_element() or friends + * @datalen: same data length as passed to for_each_element() or friends + * + * This function returns %true if all the data was parsed or considered + * while walking the elements. Only use this if your for_each_element() + * loop cannot be broken out of, otherwise it always returns %false. + * + * If some data was malformed, this returns %false since the last parsed + * element will not fill the whole remaining data. + */ +static inline bool for_each_element_completed(const struct element *element, + const void *data, size_t datalen) +{ + return (const u8 *)element == (const u8 *)data + datalen; +} + #endif /* LINUX_IEEE80211_H */ |