Re: trezor-agent: using trezor as gpg key

[Attila Lendvai <attila@lendvai.name>]

> strace -f trezor-gpg-agent 2>&1 |grep /dev

this helped a lot, thank you!

trezor-gpg-agent tries to open /dev/bus/usb/001/010, and a whole bunch
of files and dirs under /sys/bus/usb/devices/, i.e. it did *not* touch
/dev/hidraw0 nor /dev/usb/hiddev0.

the latter of which is not even covered by the trezor udev rules:

https://github.com/trezor/trezor-firmware/blob/master/common/udev/51-trezor.rules


> Even then, it only works fine once one logs out and back in, and at
> the time of login have the usb device already be connected. I think
> that's a bug in our elogind (sigh).


luckily this seems to work fine for trezor. i have rebooted with it
being unplugged, then plugged it in, and the group of the relevant
files under /dev/ were properly `plugdev`.

FTR, i didn't have my udev rules set up properly. i wrongly assumed
that it's enough to just install the trezord-udev-rules package, but
it's not.

the proper config was:

- install trezord-udev-rules system-wide

- add `plugdev` to your user's supplementary-groups

- append this to your services: (udev-rules-service 'trezor trezord-udev-rules #:groups '("plugdev"))

now, moving on to updating the trezor packages.

- attila
PGP: 5D5F 45C7 DFCD 0A39