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>
Change-Id: I3b63fe261116dd823cb5707b752f86e30710065c
CRs-fixed: 2399972
Git-commit: 49a68e0d88890060a2b9b6c6ad1ec53eb50abccf
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next.git
Signed-off-by: Peng Xu <pxu@codeaurora.org>
This commit is contained in:
Peng Xu 2019-02-19 15:05:52 -08:00
parent cf918fc2c3
commit 48f1a75601
3 changed files with 149 additions and 33 deletions

View file

@ -2019,15 +2019,29 @@ struct cfg80211_bss {
};
/**
* ieee80211_bss_get_ie - find IE with given ID
* ieee80211_bss_get_elem - find element 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);
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
* @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.
*/
static inline const u8 *ieee80211_bss_get_ie(struct cfg80211_bss *bss, u8 id)
{
return (void *)ieee80211_bss_get_elem(bss, id);
}
/**
@ -4669,6 +4683,33 @@ 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
*
@ -4693,9 +4734,44 @@ 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
@ -4717,6 +4793,28 @@ 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
*
@ -4738,6 +4836,25 @@ 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
*
@ -4754,8 +4871,12 @@ 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);
}
/**
* DOC: Regulatory enforcement infrastructure

View file

@ -650,48 +650,43 @@ 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);
/**
* enum bss_compare_mode - BSS compare mode

View file

@ -773,7 +773,7 @@ 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;
@ -781,9 +781,9 @@ 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)
{