cfg80211: add various struct element finding helpers
We currently have a number of helpers to find elements that just
return a u8 *, change those to return a struct element and add
inlines to deal with the u8 * compatibility.
Note that the match behaviour is changed to start the natch at
the data, so conversion from _ie_match to _elem_match need to
be done carefully.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/wireless/scan.c b/net/wireless/scan.c
index c7f64bb..d2c9ca5 100644
--- a/net/wireless/scan.c
+++ b/net/wireless/scan.c
@@ -480,48 +480,43 @@ void cfg80211_bss_expire(struct cfg80211_registered_device *rdev)
__cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE);
}
-const u8 *cfg80211_find_ie_match(u8 eid, const u8 *ies, int len,
- const u8 *match, int match_len,
- int match_offset)
+const struct element *
+cfg80211_find_elem_match(u8 eid, const u8 *ies, unsigned int len,
+ const u8 *match, unsigned int match_len,
+ unsigned int match_offset)
{
const struct element *elem;
- /* match_offset can't be smaller than 2, unless match_len is
- * zero, in which case match_offset must be zero as well.
- */
- if (WARN_ON((match_len && match_offset < 2) ||
- (!match_len && match_offset)))
- return NULL;
-
for_each_element_id(elem, eid, ies, len) {
- if (elem->datalen >= match_offset - 2 + match_len &&
- !memcmp(elem->data + match_offset - 2, match, match_len))
- return (void *)elem;
+ if (elem->datalen >= match_offset + match_len &&
+ !memcmp(elem->data + match_offset, match, match_len))
+ return elem;
}
return NULL;
}
-EXPORT_SYMBOL(cfg80211_find_ie_match);
+EXPORT_SYMBOL(cfg80211_find_elem_match);
-const u8 *cfg80211_find_vendor_ie(unsigned int oui, int oui_type,
- const u8 *ies, int len)
+const struct element *cfg80211_find_vendor_elem(unsigned int oui, int oui_type,
+ const u8 *ies,
+ unsigned int len)
{
- const u8 *ie;
+ const struct element *elem;
u8 match[] = { oui >> 16, oui >> 8, oui, oui_type };
int match_len = (oui_type < 0) ? 3 : sizeof(match);
if (WARN_ON(oui_type > 0xff))
return NULL;
- ie = cfg80211_find_ie_match(WLAN_EID_VENDOR_SPECIFIC, ies, len,
- match, match_len, 2);
+ elem = cfg80211_find_elem_match(WLAN_EID_VENDOR_SPECIFIC, ies, len,
+ match, match_len, 0);
- if (ie && (ie[1] < 4))
+ if (!elem || elem->datalen < 4)
return NULL;
- return ie;
+ return elem;
}
-EXPORT_SYMBOL(cfg80211_find_vendor_ie);
+EXPORT_SYMBOL(cfg80211_find_vendor_elem);
static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
const u8 *ssid, size_t ssid_len)