Question regarding use of 'luci.sys.wifi.getiwinfo'

[dibdot]

Hi Jo,

currently I would like to add WPA3 support to luci-app-travelmate. In the past I've used 'luci.sys.wifi.getiwinfo' to gather all relevant information on my wifi scan result page, e.g.:

    local iw    = luci.sys.wifi.getiwinfo(dev)
    luci.util.dumptable(iw.scanlist)

If I check the debug output, the encryption description is usually OK, even for the new WPA3 modes ... only the WPA2/WPA3 mixed mode seems to be broken, e.g.:

Wed Oct 16 15:35:48 2019 daemon.err uhttpd[2813]: 2 table: 0x55dfcad0
Wed Oct 16 15:35:48 2019 daemon.err uhttpd[2813]:   encryption  table: 0x55dfcb30
Wed Oct 16 15:35:48 2019 daemon.err uhttpd[2813]:       enabled true
Wed Oct 16 15:35:48 2019 daemon.err uhttpd[2813]:       auth_algs   table: 0x55dfda80
Wed Oct 16 15:35:48 2019 daemon.err uhttpd[2813]:       description WPA2 PSK (CCMP)
Wed Oct 16 15:35:48 2019 daemon.err uhttpd[2813]:       wep false
Wed Oct 16 15:35:48 2019 daemon.err uhttpd[2813]:       auth_suites table: 0x55dfda20
Wed Oct 16 15:35:48 2019 daemon.err uhttpd[2813]:           1   PSK
Wed Oct 16 15:35:48 2019 daemon.err uhttpd[2813]:       wpa 6
Wed Oct 16 15:35:48 2019 daemon.err uhttpd[2813]:       pair_ciphers    table: 0x55dfcb80
Wed Oct 16 15:35:48 2019 daemon.err uhttpd[2813]:           1   CCMP
Wed Oct 16 15:35:48 2019 daemon.err uhttpd[2813]:       group_ciphers   table: 0x55dfd9f0
Wed Oct 16 15:35:48 2019 daemon.err uhttpd[2813]:   quality_max 70
Wed Oct 16 15:35:48 2019 daemon.err uhttpd[2813]:   ssid    WPA3
Wed Oct 16 15:35:48 2019 daemon.err uhttpd[2813]:   channel 1
Wed Oct 16 15:35:48 2019 daemon.err uhttpd[2813]:   signal  -34
Wed Oct 16 15:35:48 2019 daemon.err uhttpd[2813]:   bssid   06:F0:21:18:25:F9
Wed Oct 16 15:35:48 2019 daemon.err uhttpd[2813]:   mode    Master
Wed Oct 16 15:35:48 2019 daemon.err uhttpd[2813]:   quality 70

In comparison the (correct) output of 'iwinfo radio1 scan' on the same device/configuration, e.g.:

Cell 02 - Address: 06:F0:21:18:25:F9
          ESSID: "WPA3"
          Mode: Master  Channel: 1
          Signal: -32 dBm  Quality: 70/70
          Encryption: mixed WPA2/WPA3 PSK/SAE (CCMP)

Is it still "allowed" to use the getiwinfo function or should I use another approach to get these kind of information?

BTW: Currently 'iwinfo scan' didn't list "hidden" APs, seems to be a regression IMHO.

Thanks for your support!

[jow-]

Hi,

I'll fix the mixed WPA3 reporting. About hidden scan results; what do you expect to receive? An entry with the SSID set to an empty string like iw does it?

Cheers, Jo

[dibdot]

Hi,

thanks for the fast response. If I remember correctly, iwinfo has reported "unknown" as ssid for hidden networks in the past.

[jow-]

Okay, I checked how iw reacts to hidden SSIDs and simply reports SSID: (empty string). I'll do the same for iwinfo. Returning unknown in the Lua table is not ideal as there might be a visible network called unknown.

[dibdot]

OK, I'll change that in travelmate then. In the past the hidden unknown ssid was delivered without double quotes, while all real ssid are protected by double quotes.

[jow-]

This is right for the iwinfo ... scan cli output, but the Lua table data does not quote the SSIDs.

[dibdot]

Yep, you're right. Travelmate backend uses iwinfo scan cli, while the luci frontend will use the lua table data ... maybe not the best approach. ;-)

[jow-]

Okay, I'm going to push my fixes now. For hidden networks, the .ssid field in the Lua tables will be unset / not existing, so you can use something like local ssid = entry.ssid or "unknown"

[dibdot]

That's cool - many thanks! Does it fix the iwinfo scan cli, too? Because currently these hidden stations won't be listed at all.

[jow-]

Yes, it will fix both places. The error actually happens when scanning is performed through wpa_supplicant instead of nl80211, in this case entries without SSID were incorrectly skipped.

[dibdot]

Perfect, thanks again!

[jow-]

Updates pushed to master and 19.07