diff options
author | Johannes Berg <johannes.berg@intel.com> | 2019-02-07 21:44:41 +0100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-10-17 13:42:21 -0700 |
commit | c48986ff2476fddad67b47467e308a1d7c17c988 (patch) | |
tree | 9888f6796e895e4d50df6b3861a1abca4c561a7c /net/wireless | |
parent | 8f68571b6a8a1ab1a24df704a95784f446ae0db1 (diff) |
cfg80211: add and use strongly typed element iteration macros
commit 0f3b07f027f87a38ebe5c436490095df762819be upstream.
Rather than always iterating elements from frames with pure
u8 pointers, add a type "struct element" that encapsulates
the id/datalen/data format of them.
Then, add the element iteration macros
* for_each_element
* for_each_element_id
* for_each_element_extid
which take, as their first 'argument', such a structure and
iterate through a given u8 array interpreting it as elements.
While at it and since we'll need it, also add
* for_each_subelement
* for_each_subelement_id
* for_each_subelement_extid
which instead of taking data/length just take an outer element
and use its data/datalen.
Also add for_each_element_completed() to determine if any of
the loops above completed, i.e. it was able to parse all of
the elements successfully and no data remained.
Use for_each_element_id() in cfg80211_find_ie_match() as the
first user of this.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/wireless')
-rw-r--r-- | net/wireless/scan.c | 14 |
1 files changed, 6 insertions, 8 deletions
diff --git a/net/wireless/scan.c b/net/wireless/scan.c index 435f904c1be5..c60be11b5e08 100644 --- a/net/wireless/scan.c +++ b/net/wireless/scan.c @@ -407,6 +407,8 @@ 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 *elem; + /* match_offset can't be smaller than 2, unless match_len is * zero, in which case match_offset must be zero as well. */ @@ -414,14 +416,10 @@ const u8 *cfg80211_find_ie_match(u8 eid, const u8 *ies, int len, (!match_len && match_offset))) return NULL; - while (len >= 2 && len >= ies[1] + 2) { - if ((ies[0] == eid) && - (ies[1] + 2 >= match_offset + match_len) && - !memcmp(ies + match_offset, match, match_len)) - return ies; - - len -= ies[1] + 2; - ies += ies[1] + 2; + 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; } return NULL; |