Encryption problems with nl80211

[Krishna Chaitanya]

On Wed, Oct 28, 2015 at 12:11 AM, Dan Williams <dcbw at redhat.com> wrote:
> On Tue, 2015-10-27 at 18:16 +0100, simo wrote:
>> Hi, I am Simon and I am new in this mail list.
>>
>> I am experiencing problems enabling encryption key after creating an
>> IBSS network through wpa_supplicant.
>
> It looks like the error is coming from the kernel mac80211/cfg80211 WiFi
> stack in nl80211_key_allowed().  That function returns an error if there
> is not yet any "current_bss", which is probably the case here.  To me it
> looks like a mismatch in expectations between the kernel and
> wpa_supplicant about how IBSS WEP is supposed to be configured.
>
> wpas_start_assoc_cb() - sets up parameters for IBSS create/join
> -- kernel cfg80211 has current_bss = NULL
> wpas_start_assoc_cb() calls wpa_set_wep_keys()
> -- kernel cfg80211 rejects set_keys request because current_bss == NULL
> wpas_start_assoc_cb() calls wpa_drv_associate() to being association
> -- kernel driver creates new IBSS, sends EVENT_IBSS_JOINED
> -- kernel cfg80211 calls __cfg80211_ibss_joined() and sets current_bss
>
> What's odd is that none of this code in the kernel or supplicant has
> really changed since early 2013, so its either been broken for a long
> time, or I'm missing something completely about when current_bss gets
> set.
>
> Dan
>
>> wlan0: Trying to associate with SSID 'my-net-302'
>> wlan0: Cancelling scan request
>> wlan0: WPA: clearing own WPA/RSN IE
>> wlan0: Automatic auth_alg selection: 0x1
>> wlan0: WPA: clearing AP WPA IE
>> wlan0: WPA: clearing AP RSN IE
>> wlan0: WPA: clearing own WPA/RSN IE
>> wpa_driver_nl80211_set_key: ifindex=3 (wlan0) alg=1 addr=(nil) key_idx=0
>> set_tx=1 seq_len=0 key_len=5
>> nl80211: KEY_DATA - hexdump(len=5): [REMOVED]
>> nl80211: set_key failed; err=-67 Link has been severed)
>
> ^^^ the error
> <snip>
>
>> nl80211: Event message available
>> nl80211: Drv Event 43 (NL80211_CMD_JOIN_IBSS) received for wlan0
>> nl80211: IBSS 12:24:21:59:87:d0 joined
>> nl80211: IBSS-joined on 2412 MHz
>> nl80211: Operating frequency for the associated BSS from scan results:
>> 2412 MHz
>> nl80211: IBSS on frequency 2412 MHz
>> wlan0: Event ASSOC (0) received
>> wlan0: State: ASSOCIATING -> ASSOCIATED
>
> Then reports success creating/joining the adhoc network.  But of course,
> since the key set failed, the network is not encrypted.
set_key after association is successful, the failure before association
can be ignored. This is not a problem.


wlan0: State: ASSOCIATED -> COMPLETED
wlan0: Radio work 'connect'@0xfab20 done in 0.603215 seconds
wlan0: CTRL-EVENT-CONNECTED - Connection to 12:24:21:59:87:d0 completed
[id=0 id_str=]
nl80211: Set wlan0 operstate 0->1 (UP)
netlink: Operstate: ifindex=3 linkmode=-1 (no change), operstate=6
(IF_OPER_UP)
wlan0: Cancelling scan request
wpa_driver_nl80211_set_key: ifindex=3 (wlan0) alg=1 addr=(nil) key_idx=0
set_tx=1 seq_len=0 key_len=5
nl80211: KEY_DATA - hexdump(len=5): [REMOVED]
RTM_NEWLINK: ifi_index=3 ifname=wlan0 operstate=6 linkmode=1
ifi_family=0 ifi_flags=0x11043 ([UP][RUNNING][LOWER_


-- 
Thanks,
Regards,
Chaitanya T K.