nixos/dhparams: Turn params into a submodule

We're going to implement an option which allows us to turn off stateful
handling of Diffie-Hellman parameter files by putting them into the Nix
store.

However, modules now might need a way to reference these files, so we
add a now path option to every param specified, which carries a
read-only value of the path where to find the corresponding DH params
file.

I've also improved the description of security.dhparams.params a bit so
that it uses <warning/> and <note/>.

The NixOS VM test also reflects this change and checks whether the old
way to specify the bit size still works.

Signed-off-by: aszlig <aszlig@nix.build>
Cc: @Ekleog

0 files changed, 0 insertions, 0 deletions