Disabling 2G and null-ciphered connections

[Aleksander Morgado]

Hey,

On Sun, Aug 13, 2023 at 9:06 PM Tom Isaacson <tom.isaacson at teknique.com> wrote:
>
> I just came across this article:
> https://security.googleblog.com/2023/08/android-14-introduces-first-of-its-kind.html
>
> When I do "mmcli --modem=0" I can see the modes:
>   Modes    |              supported: allowed: 2g; preferred: none
>            |                         allowed: 3g; preferred: none
>            |                         allowed: 4g; preferred: none
>            |                         allowed: 2g, 3g; preferred: 3g
>            |                         allowed: 2g, 3g; preferred: 2g
>            |                         allowed: 2g, 4g; preferred: 4g
>            |                         allowed: 2g, 4g; preferred: 2g
>            |                         allowed: 3g, 4g; preferred: 4g
>            |                         allowed: 3g, 4g; preferred: 3g
>            |                         allowed: 2g, 3g, 4g; preferred: 4g
>            |                         allowed: 2g, 3g, 4g; preferred: 3g
>            |                         allowed: 2g, 3g, 4g; preferred: 2g
>            |                current: allowed: 2g, 3g, 4g; preferred: 4g
>
> But I can't figure out how to change them to disable 2G. Can I do this
> via a NetworkManager profile?
>

They cannot be disabled with a NM profile, AFAIK. You can do it with mmcli e.g.
  mmcli -m a --set-allowed-modes="3g|4g" --set-preferred-mode=4g

> What about disabling support for null-ciphered connections? Is that supported?
>

I don't think there's any generic modem control command that allows
doing this, although I may be mistaken. Maybe QMI has something, or
vendor-specific AT commands. My impression though is that this setting
may be strictly configured in the carrier settings in the modem, if
carrier settings are being applied.

-- 
Aleksander