nixpkgs/nixos/tests/pam/pam-ussh.nix
Luke Granger-Brown 1853015550 nixos/pam: add support for pam-ussh
pam-ussh allows authorizing using an SSH certificate stored in your
SSH agent, in a similar manner to pam-ssh-agent-auth, but for
certificates rather than raw public keys.
2022-03-13 17:31:46 +00:00

71 lines
1.9 KiB
Nix

import ../make-test-python.nix ({ pkgs, lib, ... }:
let
testOnlySSHCredentials = pkgs.runCommand "pam-ussh-test-ca" {
nativeBuildInputs = [ pkgs.openssh ];
} ''
mkdir $out
ssh-keygen -t ed25519 -N "" -f $out/ca
ssh-keygen -t ed25519 -N "" -f $out/alice
ssh-keygen -s $out/ca -I "alice user key" -n "alice,root" -V 19700101:forever $out/alice.pub
ssh-keygen -t ed25519 -N "" -f $out/bob
ssh-keygen -s $out/ca -I "bob user key" -n "bob" -V 19700101:forever $out/bob.pub
'';
makeTestScript = user: pkgs.writeShellScript "pam-ussh-${user}-test-script" ''
set -euo pipefail
eval $(${pkgs.openssh}/bin/ssh-agent)
mkdir -p $HOME/.ssh
chmod 700 $HOME/.ssh
cp ${testOnlySSHCredentials}/${user}{,.pub,-cert.pub} $HOME/.ssh
chmod 600 $HOME/.ssh/${user}
chmod 644 $HOME/.ssh/${user}{,-cert}.pub
set -x
${pkgs.openssh}/bin/ssh-add $HOME/.ssh/${user}
${pkgs.openssh}/bin/ssh-add -l &>2
exec sudo id -u -n
'';
in {
name = "pam-ussh";
meta.maintainers = with lib.maintainers; [ lukegb ];
machine =
{ ... }:
{
users.users.alice = { isNormalUser = true; extraGroups = [ "wheel" ]; };
users.users.bob = { isNormalUser = true; extraGroups = [ "wheel" ]; };
security.pam.ussh = {
enable = true;
authorizedPrincipals = "root";
caFile = "${testOnlySSHCredentials}/ca.pub";
};
security.sudo = {
enable = true;
extraConfig = ''
Defaults lecture="never"
'';
};
};
testScript =
''
with subtest("alice should be allowed to escalate to root"):
machine.succeed(
'su -c "${makeTestScript "alice"}" -l alice | grep root'
)
with subtest("bob should not be allowed to escalate to root"):
machine.fail(
'su -c "${makeTestScript "bob"}" -l bob | grep root'
)
'';
})