Commit 49a68e0d authored by Johannes Berg's avatar Johannes Berg
Browse files

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: default avatarJohannes Berg <johannes.berg@intel.com>
parent c17e28d1

include/net/cfg80211.h

+128 −7
Original line number Diff line number Diff line
@@ -2062,16 +2062,30 @@ struct cfg80211_bss { 
	u8 priv[0] __aligned(sizeof(void *));

};



/**

 * ieee80211_bss_get_elem - find element with given ID

 * @bss: the bss to search

 * @id: the element ID

 *

 * Note that the return value is an RCU-protected pointer, so

 * rcu_read_lock() must be held when calling this function.

 * Return: %NULL if not found.

 */

const struct element *ieee80211_bss_get_elem(struct cfg80211_bss *bss, u8 id);



/**

 * ieee80211_bss_get_ie - find IE with given ID

 * @bss: the bss to search

 * @ie: the IE ID

 * @id: the element ID

 *

 * Note that the return value is an RCU-protected pointer, so

 * rcu_read_lock() must be held when calling this function.

 * Return: %NULL if not found.

 */

const u8 *ieee80211_bss_get_ie(struct cfg80211_bss *bss, u8 ie);

static inline const u8 *ieee80211_bss_get_ie(struct cfg80211_bss *bss, u8 id)

{

	return (void *)ieee80211_bss_get_elem(bss, id);

}





/**
@@ -4999,6 +5013,33 @@ void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list, 
unsigned int cfg80211_classify8021d(struct sk_buff *skb,

				    struct cfg80211_qos_map *qos_map);



/**

 * cfg80211_find_elem_match - match information element and byte array in data

 *

 * @eid: element ID

 * @ies: data consisting of IEs

 * @len: length of data

 * @match: byte array to match

 * @match_len: number of bytes in the match array

 * @match_offset: offset in the IE data where the byte array should match.

 *	Note the difference to cfg80211_find_ie_match() which considers

 *	the offset to start from the element ID byte, but here we take

 *	the data portion instead.

 *

 * Return: %NULL if the element ID could not be found or if

 * the element is invalid (claims to be longer than the given

 * data) or if the byte array doesn't match; otherwise return the

 * requested element struct.

 *

 * Note: There are no checks on the element length other than

 * having to fit into the given data and being large enough for the

 * byte array to match.

 */

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);



/**

 * cfg80211_find_ie_match - match information element and byte array in data

 *
@@ -5023,9 +5064,44 @@ unsigned int cfg80211_classify8021d(struct sk_buff *skb, 
 * having to fit into the given data and being large enough for the

 * byte array to match.

 */

const u8 *cfg80211_find_ie_match(u8 eid, const u8 *ies, int len,

				 const u8 *match, int match_len,

				 int match_offset);

static inline const u8 *

cfg80211_find_ie_match(u8 eid, const u8 *ies, unsigned int len,

		       const u8 *match, unsigned int match_len,

		       unsigned int match_offset)

{

	/* 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;



	return (void *)cfg80211_find_elem_match(eid, ies, len,

						match, match_len,

						match_offset ?

							match_offset - 2 : 0);

}



/**

 * cfg80211_find_elem - find information element in data

 *

 * @eid: element ID

 * @ies: data consisting of IEs

 * @len: length of data

 *

 * Return: %NULL if the element ID could not be found or if

 * the element is invalid (claims to be longer than the given

 * data) or if the byte array doesn't match; otherwise return the

 * requested element struct.

 *

 * Note: There are no checks on the element length other than

 * having to fit into the given data.

 */

static inline const struct element *

cfg80211_find_elem(u8 eid, const u8 *ies, int len)

{

	return cfg80211_find_elem_match(eid, ies, len, NULL, 0, 0);

}



/**

 * cfg80211_find_ie - find information element in data
@@ -5047,6 +5123,28 @@ static inline const u8 *cfg80211_find_ie(u8 eid, const u8 *ies, int len) 
	return cfg80211_find_ie_match(eid, ies, len, NULL, 0, 0);

}



/**

 * cfg80211_find_ext_elem - find information element with EID Extension in data

 *

 * @ext_eid: element ID Extension

 * @ies: data consisting of IEs

 * @len: length of data

 *

 * Return: %NULL if the etended element could not be found or if

 * the element is invalid (claims to be longer than the given

 * data) or if the byte array doesn't match; otherwise return the

 * requested element struct.

 *

 * Note: There are no checks on the element length other than

 * having to fit into the given data.

 */

static inline const struct element *

cfg80211_find_ext_elem(u8 ext_eid, const u8 *ies, int len)

{

	return cfg80211_find_elem_match(WLAN_EID_EXTENSION, ies, len,

					&ext_eid, 1, 0);

}



/**

 * cfg80211_find_ext_ie - find information element with EID Extension in data

 *
@@ -5068,6 +5166,25 @@ static inline const u8 *cfg80211_find_ext_ie(u8 ext_eid, const u8 *ies, int len) 
				      &ext_eid, 1, 2);

}



/**

 * cfg80211_find_vendor_elem - find vendor specific information element in data

 *

 * @oui: vendor OUI

 * @oui_type: vendor-specific OUI type (must be < 0xff), negative means any

 * @ies: data consisting of IEs

 * @len: length of data

 *

 * Return: %NULL if the vendor specific element ID could not be found or if the

 * element is invalid (claims to be longer than the given data); otherwise

 * return the element structure for the requested element.

 *

 * Note: There are no checks on the element length other than having to fit into

 * the given data.

 */

const struct element *cfg80211_find_vendor_elem(unsigned int oui, int oui_type,

						const u8 *ies,

						unsigned int len);



/**

 * cfg80211_find_vendor_ie - find vendor specific information element in data

 *
@@ -5084,8 +5201,12 @@ static inline const u8 *cfg80211_find_ext_ie(u8 ext_eid, const u8 *ies, int len) 
 * Note: There are no checks on the element length other than having to fit into

 * the given data.

 */

const u8 *cfg80211_find_vendor_ie(unsigned int oui, int oui_type,

				  const u8 *ies, int len);

static inline const u8 *

cfg80211_find_vendor_ie(unsigned int oui, int oui_type,

			const u8 *ies, unsigned int len)

{

	return (void *)cfg80211_find_vendor_elem(oui, oui_type, ies, len);

}



/**

 * cfg80211_send_layer2_update - send layer 2 update frame

net/wireless/scan.c

+17 −22
Original line number Diff line number Diff line
@@ -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)

net/wireless/util.c

+3 −3
Original line number Diff line number Diff line
@@ -776,7 +776,7 @@ unsigned int cfg80211_classify8021d(struct sk_buff *skb, 
}

EXPORT_SYMBOL(cfg80211_classify8021d);



const u8 *ieee80211_bss_get_ie(struct cfg80211_bss *bss, u8 ie)

const struct element *ieee80211_bss_get_elem(struct cfg80211_bss *bss, u8 id)

{

	const struct cfg80211_bss_ies *ies;
@@ -784,9 +784,9 @@ const u8 *ieee80211_bss_get_ie(struct cfg80211_bss *bss, u8 ie) 
	if (!ies)

		return NULL;



	return cfg80211_find_ie(ie, ies->data, ies->len);

	return cfg80211_find_elem(id, ies->data, ies->len);

}

EXPORT_SYMBOL(ieee80211_bss_get_ie);

EXPORT_SYMBOL(ieee80211_bss_get_elem);



void cfg80211_upload_connect_keys(struct wireless_dev *wdev)

{

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