No OWE transition mode element on hidden OWE network

[James Prestwood]

Hi,

While playing around with OWE transition mode I noticed the hidden OWE
network has no OWE transition mode element. The two network configs are
attached.

According to the OWE Spec v1.1, section 2.2.1:

"The OWE BSS shall include the OWE Transition Mode element in all
Beacon and Probe Response frames to encapsulate the BSSID and SSID of
the Open BSS."

I figured it was a misconfiguration but then I found the following code
in src/ap/ieee802_11_shared.c:

static int hostapd_eid_owe_trans_enabled(struct hostapd_data *hapd)
{
	return hapd->conf->owe_transition_ssid_len > 0 &&
		!is_zero_ether_addr(hapd->conf->owe_transition_bssid);
}

This is called prior to appending the OWE transition element so for the
hidden SSID (where ssid_len < 0) it returns false and the IE is never
built/appended.

Removing the SSID length check seems to fix this and I see the OWE
transition element for the hidden OWE network. Attached is the patch to
remove this length check.

Thanks,
James
-------------- next part --------------
ssid=owe-hidden
bssid=a6:44:ce:d8:61:6f
channel=1
ignore_broadcast_ssid=1
ieee80211w=1

wpa=2
wpa_key_mgmt=OWE
rsn_pairwise=CCMP
owe_transition_ssid="transition"
owe_transition_bssid=fe:e1:de:ce:a5:ed
-------------- next part --------------
channel=1
ssid=transition
bssid=fe:e1:de:ce:a5:ed
owe_transition_ssid="owe-hidden"
owe_transition_bssid=a6:44:ce:d8:61:6f
-------------- next part --------------
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