cfg80211: comprehensively check station changes

The station change API isn't being checked properly before
drivers are called, and as a result it is difficult to see
what should be allowed and what not.

In order to comprehensively check the API parameters parse
everything first, and then have the driver call a function
(cfg80211_check_station_change()) with the additionally
information about the kind of station that is being changed;
this allows the function to make better decisions than the
old code could.

While at it, also add a few checks, particularly in mesh
and clarify the TDLS station lifetime in documentation.

To be able to reduce a few checks, ignore any flag set bits
when the mask isn't set, they shouldn't be applied then.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Johannes Berg
2013-02-15 00:48:33 +01:00
parent ff276691e9
commit 77ee7c891a
5 changed files with 311 additions and 174 deletions

View File

@@ -677,6 +677,49 @@ struct station_parameters {
u8 ext_capab_len;
};
/**
* enum cfg80211_station_type - the type of station being modified
* @CFG80211_STA_AP_CLIENT: client of an AP interface
* @CFG80211_STA_AP_MLME_CLIENT: client of an AP interface that has
* the AP MLME in the device
* @CFG80211_STA_AP_STA: AP station on managed interface
* @CFG80211_STA_IBSS: IBSS station
* @CFG80211_STA_TDLS_PEER_SETUP: TDLS peer on managed interface (dummy entry
* while TDLS setup is in progress, it moves out of this state when
* being marked authorized; use this only if TDLS with external setup is
* supported/used)
* @CFG80211_STA_TDLS_PEER_ACTIVE: TDLS peer on managed interface (active
* entry that is operating, has been marked authorized by userspace)
* @CFG80211_STA_MESH_PEER_NONSEC: peer on mesh interface (non-secured)
* @CFG80211_STA_MESH_PEER_SECURE: peer on mesh interface (secured)
*/
enum cfg80211_station_type {
CFG80211_STA_AP_CLIENT,
CFG80211_STA_AP_MLME_CLIENT,
CFG80211_STA_AP_STA,
CFG80211_STA_IBSS,
CFG80211_STA_TDLS_PEER_SETUP,
CFG80211_STA_TDLS_PEER_ACTIVE,
CFG80211_STA_MESH_PEER_NONSEC,
CFG80211_STA_MESH_PEER_SECURE,
};
/**
* cfg80211_check_station_change - validate parameter changes
* @wiphy: the wiphy this operates on
* @params: the new parameters for a station
* @statype: the type of station being modified
*
* Utility function for the @change_station driver method. Call this function
* with the appropriate station type looking up the station (and checking that
* it exists). It will verify whether the station change is acceptable, and if
* not will return an error code. Note that it may modify the parameters for
* backward compatibility reasons, so don't use them before calling this.
*/
int cfg80211_check_station_change(struct wiphy *wiphy,
struct station_parameters *params,
enum cfg80211_station_type statype);
/**
* enum station_info_flags - station information flags
*
@@ -1770,9 +1813,8 @@ struct cfg80211_gtk_rekey_data {
* @change_station: Modify a given station. Note that flags changes are not much
* validated in cfg80211, in particular the auth/assoc/authorized flags
* might come to the driver in invalid combinations -- make sure to check
* them, also against the existing state! Also, supported_rates changes are
* not checked in station mode -- drivers need to reject (or ignore) them
* for anything but TDLS peers.
* them, also against the existing state! Drivers must call
* cfg80211_check_station_change() to validate the information.
* @get_station: get station information for the station identified by @mac
* @dump_station: dump station callback -- resume dump at index @idx
*