ping setuid error

[573]

nix --extra-experimental-features nix-command --extra-experimental-features flakes shell nixpkgs#iputils -c ping google.com -c4

errors

ping: setuid: Function not implemented

[SuperSandro2000]

ping requires root or a setuid binary.

[expelledboy]

And how do you install setuid? There are suggestion that you need to use the security wrapper

security.wrappers = {
  ping = {
    owner = "root";
    group = "root";
    capabilities = "cap_net_raw+p";
    source = "${pkgs.iputils.out}/bin/ping";
  };
};

But I am unsure where to put this in the flake install of nix on droid

[Gerschtli]

This does not work in nix-on-droid. These are NixOS options. Also you need to root your device otherwise you are restricted to a unprivileged user.

[chenx6]

But ping command in Termux is working well. It seems like ping command in Termux is just a wrapper of system's ping command.

~ $ cat /data/data/com.termux/files/usr/bin/ping
#!/data/data/com.termux/files/usr/bin/sh
unset LD_LIBRARY_PATH LD_PRELOAD
PATH=$PATH:/system/bin exec /system/bin/ping "$@"

[Pablo1107]

But ping command in Termux is working well. It seems like ping command in Termux is just a wrapper of system's ping command.

~ $ cat /data/data/com.termux/files/usr/bin/ping
#!/data/data/com.termux/files/usr/bin/sh
unset LD_LIBRARY_PATH LD_PRELOAD
PATH=$PATH:/system/bin exec /system/bin/ping "$@"

Trying to run /system/bin/ping google.com returns no such file or directory in Nix on Droid.

[ettom]

I got ping to work like this: Modify /system/bin/login by adding -b /system:/uppersystem to the proot command line. Restart the app and run /uppersystem/bin/linker64 /uppersystem/bin/ping. nix-on-droid seems to mask the /system/bin and /android/system/bin directories somehow, but I don't quite get the logic. Perhaps it could expose the real /system/bin directory in a similar manner?

[t184256]

Nice, wonder if that could somehow be used towards https://github.com/t184256/nix-on-droid/issues/221

nix-on-droid seems to mask the /system/bin and /android/system/bin directories somehow, but I don't quite get the logic. Perhaps it could expose the real /system/bin directory in a similar manner?

It might be because of a proot-pseudomount to /bin, which we need for /bin/sh?

You might be interested in commits in bin-less branch.

[ettom]

It might be because of a proot-pseudomount to /bin, which we need for /bin/sh?

Just to be sure, are you referring to this line? But then why is /bin a symlink to /system/bin? And why doesn't /android/system/bin contain the contents of the upper /system/bin (due to -b /:/android)?

[Pablo1107]

I got ping to work like this: Modify /system/bin/login by adding -b /system:/uppersystem to the proot command line. Restart the app and run /uppersystem/bin/linker64 /uppersystem/bin/ping. nix-on-droid seems to mask the /system/bin and /android/system/bin directories somehow, but I don't quite get the logic. Perhaps it could expose the real /system/bin directory in a similar manner?

Is there a way to declaratively modify the login script from a Nix config file?

Or maybe just add a initialization script on switch.

[ettom]

Is there a way to declaratively modify the login script from a Nix config file?

Or maybe just add a initialization script on switch.

I don't think there is a direct way. What you can do is build your own bootstrap zipball with this change per the instructions in the README. I suppose you could do it with awk/sed from an initialization script too.

[t184256]

It should be enough to fork, modify login.nix and point your channel/flake to your fork.

Though when I'm experimenting with it, I usually just edit the login script directly on a spare device =)

[ettom]

It might be because of a proot-pseudomount to /bin, which we need for /bin/sh?

Just to be sure, are you referring to this line? But then why is /bin a symlink to /system/bin? And why doesn't /android/system/bin contain the contents of the upper /system/bin (due to -b /:/android)?

My bad, /android/system/bin seems to work too. So /android/system/bin/linker64 /android/system/bin/ping

[Pablo1107]

It might be because of a proot-pseudomount to /bin, which we need for /bin/sh?

Just to be sure, are you referring to this line? But then why is /bin a symlink to /system/bin? And why doesn't /android/system/bin contain the contents of the upper /system/bin (due to -b /:/android)?

My bad, /android/system/bin seems to work too. So /android/system/bin/linker64 /android/system/bin/ping

I have been using this workaround since some time but suddenly I got this error:

CANNOT LINK EXECUTABLE "/android/system/bin/ping": library "/nix/store/qbkpqssvc41v2pd9dda8s3cyxs7m0dbm-dnshack/lib/libdnshackbridge.so" needed or dlopened by "/system/bin/ping" is not accessible for the namespace "(default)"

Edit: this seems to be related to this dnshack I introduced in the past and forgot about. Without it, ping works fine.