On Wed, 2017-05-24 at 17:34 +1000, Tobin C. Harding wrote: > On Wed, May 24, 2017 at 05:27:50PM +1000, Tobin C. Harding wrote: > > Hi, > > > > I am attempting to rewrite the ks7010 WEXT driver > > (drivers/staging/ks7010) > > to use the CFG80211 API. > > > > I am reading 802.11 Wireless Networks - Matthew S. Gast for > > reference. > > > > I have some confusion regarding WEP/WPA/WPA2/RSN, ciphers, keys and > > ie's? > > > > As I understand, first there was WEP. Next we got a marketing term > > WPA > > which referred to 802.11i (which specified the protocols TKIP and > > CCMP, and also RSN). > > > > WEP vs WPA > > ---------- > > > > To add to my confusion the ks7010 code seemingly mixes up the use > > of > > WEP keys and WPA keys, to set both the WEP and the WPA keys the > > driver > > uses the same MIB requests? Yet throughout the code WEP keys and > > WPA > > keys are stored in separate structures (and treated differently). > > Oh, I just got why there is only one MIB request type - there are > only > one set of keys used by the target > > DOT11_WEP_DEFAULT_KEY_VALUE1 = 0x13020101, > DOT11_WEP_DEFAULT_KEY_VALUE2 = 0x13020102, > DOT11_WEP_DEFAULT_KEY_VALUE3 = 0x13020103, > DOT11_WEP_DEFAULT_KEY_VALUE4 = 0x13020104, > > removing 'WEP' from the defines removes the confusion here :) I could be entirely wrong, but it looks like the driver really just defines 4 "keys" which can be used for anything. For WEP, they are the 4 WEP key indexes. For RSN, they are 1 = PMK, 2 = GMK, 3 = GMK2, 4 seems unused. Because WEXT is pretty convoluted, I woudn't necessarily try to translate what eg ks_wlan_set_encode_ext() is doing directly to cfg80211, but to understand how the firmware interface works and then just write the cfg80211 code to the firmware interface. Basically, you have the following modes: a) open, no encryption b) WEP encryption (4 possible WEP keys, each either 40 or 104 bits) c) WPA/RSN (PMK and GMK are computed by wpa_supplicant and supplied to you, just need to send to firmware) most of the stuff about IW_ENCODE_ALG_* is useless for cfg80211, you just take the values that you get from userspace (eg, wpa_supplicant) for the key and the type of key and just tell the firmware to use those. The driver also has odd stuff like SME_WEP_FLAG_REQUEST that really just maps to DOT11_PRIVACY_INVOKED, so that's going to be a bit confusing for you too since that's used not just for WEP but also for WPA/RSN. So anyway, it's going to be an interesting ride for you, but I think you'll be pleasantly surprised at how much awful code you can actually remove. And to answer Johannes, this firmware looks much more fullmac than softmac; BSS selection seems left up to the firmware. You just send it a "connect with these parameters" command (HIF_INFRA_SET_REQ) including channels, SSID, BSSID, mode, etc and it does everything. So Tobin, I think that means this driver should probably implement the "connect" call like fullmac drivers do. One existing example of that is the 'brcmfmac' driver, eg brcmf_cfg80211_connect(). Dan > > If WPA is enabled are not WEP keys superfluous? > > > > WPA vs WPA2 > > ----------- > > > > Were WPA version 1 and WPA version 2 marketing terms or do they > > differ? > > > > ieee80211.h does not seem to mention WPA2 (and cfg80211.h mentions > > it > > once only in some comments) however, from cfg80211.h; > > > > * struct cfg80211_crypto_settings - Crypto settings > > * @wpa_versions: indicates which, if any, WPA versions are enabled > > * (from enum nl80211_wpa_versions) > > > > When using the CFG80211 API we do not need to worry about the > > WPA/WPA2 > > distinction? Can I drop all the WPA version 1 code from the driver? > > > > A little more information: > > > > The WEXT driver defines ciphers, from looking at ieee80211.h it > > seems > > that it uses WLAN_CIPHER_SUITE_XXX for WPA2 and for WPA it uses > > > > #define CIPHER_ID_WPA_NONE "\x00\x50\xf2\x00" > > #define CIPHER_ID_WPA_WEP40 "\x00\x50\xf2\x01" > > #define CIPHER_ID_WPA_TKIP "\x00\x50\xf2\x02" > > #define CIPHER_ID_WPA_CCMP "\x00\x50\xf2\x04" > > #define CIPHER_ID_WPA_WEP104 "\x00\x50\xf2\x05" > > > > FYI ieee80211.h has > > > > #define WLAN_OUI_MICROSOFT 0x0050f2 > > > > Thanks for taking the time to read this mail, any suggestions most > > appreciated. > > > > thanks, > > Tobin.
