Vendor specific data within a beacon frame

Bjoern Czybik wlfw at
Fri Oct 8 06:50:08 EDT 2010

Ok, I'm sorry I didn't epress myself well.

There is the struct 80211_gmt in the ieee80211_mgmt module in the 
ieeee80211_defs.h, but there is no field for vendor specific data (of 
course it will be set by the hostapd).

 From the hostapd the function ieee802_11_set_beacon(...) calls the 
wpa_driver_nl80211_set_beacon function in driver_nl80211.c (we are using 
the hostapd-0.7.3).
In wpa_driver_nl80211_set_beacon fct. the macro NLA_PUT and NLA_PUT_32 
is used to set the header and tail of a mgmt frame.

If I am right, I have to use the attribute NL80211_ATTR_IE to set 
information elements data with %NL80211_CMD_SET_MGMT_EXTRA_IE (in 
nl80211.h). But in the enum nl80211_commands is written:
     NL80211_CMD_SET_MGMT_EXTRA_IE /* reserved; not used */,

Does somebody knows how to fix it?


On 07.10.2010 20:35, Johannes Berg wrote:
> On Thu, 2010-10-07 at 11:31 -0700, Luis R. Rodriguez wrote:
>> On Thu, Oct 7, 2010 at 11:15 AM, Johannes Berg
>> <johannes at>  wrote:
>>> On Thu, 2010-10-07 at 11:11 -0700, Luis R. Rodriguez wrote:
>>> Let me quote what you wrote, but just partially:
>>>> This can be done from userspace. This is from nl80211.h:
>>>>   *      Note: This command has been removed and it is only reserved at this
>>>>   *      point to avoid re-using existing command number. The functionality this
>>>>   *      command was planned for has been provided with cleaner design with the
>>>>   *      option to specify additional IEs in NL80211_CMD_TRIGGER_SCAN,
>>>>   *      NL80211_CMD_AUTHENTICATE, NL80211_CMD_ASSOCIATE,
>>> :P
>> Yeah just noticed *after* I pasted it and sent it. Does hostapd use
>> this currently?
> No, hostapd transmits frames via injection and the data it puts into the
> beacon is conveyed with the beacon cmd -- it has never used this
> command.
> Really, what the OP is looking for is the annotated hostapd
> configuration file or the hostapd source code -- he should be able to
> figure that out for himself.
> johannes

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