Linux keyring support clarification

[sauliusvl]

The documentation states that the app supports "Linux: Secret Service (via libsecret - GNOME Keyring, KWallet)", I also see there's test infrastructure for gnome-keyring-daemon, however I'm pretty sure it doesn't work. The keyring dependency only enables linux-native, which uses keyutils, which in turn provides "a high-level API for interacting with the Linux keys subsystem" - this is the in-memory kernel key infrastructure, which is not related to user space keyring daemons, such as gnome-keyring-daemon.

I verified this by following the Quick Start example:

$ fnox get DATABASE_URL
postgresql://localhost/mydb

$ keyctl list @s
3 keys in keyring:
265325336: --alswrv  1000 65534 keyring: _uid.1000
948827869: --alswrv  1000  1000 user: keyring-rs:DATABASE_URL@fnox
386144565: ---lswrv  1000 65534 keyring: _persistent.1000

it disappears after reboot, there's no secrets visible using seahorse.

I'm not sure if using the kernel keyring is ever a viable option, as by default it's non-persistent. I suppose the correct thing to do would be to replace linux-native with sync-secret-service, which then goes through the DBus interface. I tried it, the project compiled without any other changes and worked as expected.