nixosTests.systemd: test cryptsetup support

This creates and opens a luks volume, puts its passphrase into a keyfile
and writes a /etc/crypttab. It then reboots the machine, and verifies
systemd parsed /etc/crypttab properly, and was able to unlock the volume
with the keyfile provided (as we try to mount it).

The memorySize of the VM had to be bumped, as luksFormat would otherwise
run out of memory.

1 files changed, 24 insertions, 1 deletions

diff --git a/nixos/tests/systemd.nix b/nixos/tests/systemd.nix
index a653932fb37c7..9d21f9158f3c1 100644
--- a/nixos/tests/systemd.nix
+++ b/nixos/tests/systemd.nix
@@ -4,7 +4,10 @@ import ./make-test-python.nix ({ pkgs, ... }: {
   machine = { lib, ... }: {
     imports = [ common/user-account.nix common/x11.nix ];
 
-    virtualisation.emptyDiskImages = [ 512 ];
+    virtualisation.emptyDiskImages = [ 512 512 ];
+    virtualisation.memorySize = 1024;
+
+    environment.systemPackages = [ pkgs.cryptsetup ];
 
     fileSystems = lib.mkVMOverride {
       "/test-x-initrd-mount" = {
@@ -144,5 +147,25 @@ import ./make-test-python.nix ({ pkgs, ... }: {
         assert "RuntimeWatchdogUSec=30s" in output
         assert "RebootWatchdogUSec=10m" in output
         assert "KExecWatchdogUSec=5m" in output
+
+    # Test systemd cryptsetup support
+    with subtest("systemd successfully reads /etc/crypttab and unlocks volumes"):
+        # create a luks volume and put a filesystem on it
+        machine.succeed(
+            "echo -n supersecret | cryptsetup luksFormat -q /dev/vdc -",
+            "echo -n supersecret | cryptsetup luksOpen --key-file - /dev/vdc foo",
+            "mkfs.ext3 /dev/mapper/foo",
+        )
+
+        # create a keyfile and /etc/crypttab
+        machine.succeed("echo -n supersecret > /var/lib/luks-keyfile")
+        machine.succeed("chmod 600 /var/lib/luks-keyfile")
+        machine.succeed("echo 'luks1 /dev/vdc /var/lib/luks-keyfile luks' > /etc/crypttab")
+
+        # after a reboot, systemd should unlock the volume and we should be able to mount it
+        machine.shutdown()
+        machine.succeed("systemctl status systemd-cryptsetup@luks1.service")
+        machine.succeed("mkdir -p /tmp/luks1")
+        machine.succeed("mount /dev/mapper/luks1 /tmp/luks1")
   '';
 })