This introduces an option that allows us to turn off stateful generation
of Diffie-Hellman parameters, which in some way is still "stateful" as
the generated DH params file is non-deterministic.
However what we can avoid with this is to have an increased surface for
failures during system startup, because generation of the parameters is
done during build-time.
Aside from adding a NixOS VM test it also restructures the type of the
security.dhparams.params option, so that it's a submodule.
A new defaultBitSize option is also there to allow users to set a
system-wide default.
I added a release notes entry that described what has changed and also
included a few notes for module developers using this module, as the
first usage already popped up in NixOS/nixpkgs#39507.
Thanks to @Ekleog and @abbradar for reviewing.
Always enable both tty and serial console, but set preferred console
depending on cfg.graphical.
Even in qemu graphical mode, you can switch to the serial console via
Ctrl+Alt+3.
With that being done, you also don't need to specify
`systemd.services."serial-getty@ttyS0".enable = true;` either as described in
https://nixos.wiki/wiki/Cheatsheet#Building_a_service_as_a_VM_.28for_testing.29,
as systemd automatically spawns a getty on consoles passwd via cmdline.
This also means, vms built by 'nixos-rebuild build-vm' can simply be run
properly in nographic mode by appending `-nographic` to `result/bin/run-*-vm`,
without the need to explicitly add platform-specific QEMU_KERNEL_PARAMS.
This allows to set the default bit size for all the Diffie-Hellman
parameters defined in security.dhparams.params and it's particularly
useful so that we can set it to a very low value in tests (so it doesn't
take ages to generate).
Regardless for the use in testing, this also has an impact in production
systems if the owner wants to set all of them to a different size than
2048, they don't need to set it individually for every params that are
set.
I've added a subtest to the "dhparams" NixOS test to ensure this is
working properly.
Signed-off-by: aszlig <aszlig@nix.build>
When trying to run NSD to serve the root zone, one gets the following
error message:
error: illegal name: '.'
This is because the name of the zone is used as the derivation name for
building the zone file. However, Nix doesn't allow derivation names
starting with a period.
So whenever the zone is "." now, the file name generated is "root"
instead of ".".
I also added an assertion that makes sure the user sets
services.nsd.rootServer, otherwise NSD will fail at runtime because it
prevents serving the root zone without an explicit compile-time option.
Tested this by adding a root zone to the "nsd" NixOS VM test.
Signed-off-by: aszlig <aszlig@nix.build>
Cc: @hrdinka, @qknight
lib.optional returns a singleton or an empty list. Therefore the
argument does not need to be wrapped in a list.
An alternative patch could have used lib.optionals but seems like no
more elements are going to be added to the optional list.
The following changes have been applied:
- the property `http.headers.X-Content-Type-Options` must a list of
strings rather than a serialized list
- instead of `/etc/docker/registry/config.yml` the configuration will be
written with `pkgs.writeText` and the store path will be used to run
the registry. This reduces the risk of possible impurities by relying
on the Nix store only.
- cleaned up the property paths to easy readability and reduce the
verbosity.
- enhanced the testcase to ensure that digests can be deleted as well
- the `services.docker-registry.extraConfig` object will be merged with
`registryConfig`
/cc @ironpinguin
@Ekleog writes in https://github.com/NixOS/nixpkgs/pull/39526:
> I think a default of 4096 is maybe too much? See certbot/certbot#4973;
> Let's Encrypt supposedly know what they are doing and use a
> pre-generated 2048-bit DH params (and using the same DH params as
> others is quite bad, even compared to lower bit size, if I correctly
> remember the attacks available -- because it increases by as much the
> value of breaking the group).
> Basically I don't have anything personal against 4096, but fear it may
> re-start the arms race: people like having "more security" than their
> distributions, and having NixOS already having more security than is
> actually useful (I personally don't know whether a real-size quantum
> computer will come before or after our being able to break 2048-bit
> keys, let alone 3072-bit ones -- see wikipedia for some numbers).
> So basically, I'd have set it to 3072 in order to both decrease build
> time and avoid having people setting it to 8192 and complaining about
> how slow things are, but that's just my opinion. :)
While he suggests is 3072 I'm using 2048 now, because it's the default
of "openssl dhparam". If users want to have a higher value, they can
still change it.
Signed-off-by: aszlig <aszlig@nix.build>
The ability to specify "-drive if=scsi" has been removed in QEMU version
2.12 (introduced in 3e3b39f173).
Quote from https://wiki.qemu.org/ChangeLog/2.12#Incompatible_changes:
> The deprecated way of configuring SCSI devices with "-drive if=scsi"
> on x86 has been removed. Use an appropriate SCSI controller together
> "-device scsi-hd" or "-device scsi-cd" and a corresponding "-blockdev"
> parameter instead.
So whenever the diskInterface is "scsi" we use the new way to specify
the drive and fall back to the deprecated way for the time being. The
reason why I'm not using the new way for "virtio" and "ide" as well is
because there is no simple generic way anymore to specify these.
This also turns the type of the virtualisation.qemu.diskInterface option
to be an enum, so the user knows which values are allowed but we can
also make sure the right value is provided to prevent typos.
I've tested this against a few non-disk-related NixOS VM tests but also
the installer.grub1 test (because it uses "ide" as its drive interface),
the installer.simple test (just to be sure it still works with
"virtio") and all the tests in nixos/tests/boot.nix.
In order to be able to run the grub1 test I had to go back to
8b1cf100cd (which is a known commit where
that test still works) and apply the QEMU update and this very commit,
because right now the test is broken.
Apart from the tests here in nixpkgs, I also ran another[1] test in
another repository which uses the "scsi" disk interface as well (in
comparison to most of the installer tests, this one actually failed
prior to this commit).
All of them now succeed.
[1]: 9b5a119972/tests/system/kernel/bfq.nix
Signed-off-by: aszlig <aszlig@nix.build>
Cc: @edostra, @grahamc, @dezgeg, @abbradar, @ts468
