nixos/krb5: cleanup, fix and RFC42-ify

This replaces the krb5 module's options with RFC 42-style krb5.settings
option, while greatly simplifying the code and fixing a few bugs,
namely:

- #243068 krb5: Configuration silently gets ignored when set by
  multiple modules
- not being able to use mkIf etc. inside subattributes of
  krb5.libdefaults, e.g. krb5.libdefaults.default_realm = mkIf ...

See #144575.
Closes #243068.

Co-authored-by: h7x4 <h7x4@nani.wtf>

2 files changed, 20 insertions, 16 deletions

diff --git a/nixos/tests/kerberos/heimdal.nix b/nixos/tests/kerberos/heimdal.nix
index 47f9d0285aef7..fbe2ad745bafd 100644
--- a/nixos/tests/kerberos/heimdal.nix
+++ b/nixos/tests/kerberos/heimdal.nix
@@ -9,14 +9,16 @@ import ../make-test-python.nix ({pkgs, ...}: {
     };
     krb5 = {
       enable = true;
-      kerberos = pkgs.heimdal;
-      libdefaults = {
-        default_realm = "FOO.BAR";
-      };
-      realms = {
-        "FOO.BAR" = {
-          admin_server = "machine";
-          kdc = "machine";
+      package = pkgs.heimdal;
+      settings = {
+        libdefaults = {
+          default_realm = "FOO.BAR";
+        };
+        realms = {
+          "FOO.BAR" = {
+            admin_server = "machine";
+            kdc = "machine";
+          };
         };
       };
     };
diff --git a/nixos/tests/kerberos/mit.nix b/nixos/tests/kerberos/mit.nix
index 7e427ffef0ba8..b16fc89990e39 100644
--- a/nixos/tests/kerberos/mit.nix
+++ b/nixos/tests/kerberos/mit.nix
@@ -9,14 +9,16 @@ import ../make-test-python.nix ({pkgs, ...}: {
     };
     krb5 = {
       enable = true;
-      kerberos = pkgs.krb5;
-      libdefaults = {
-        default_realm = "FOO.BAR";
-      };
-      realms = {
-        "FOO.BAR" = {
-          admin_server = "machine";
-          kdc = "machine";
+      package = pkgs.krb5;
+      settings = {
+        libdefaults = {
+          default_realm = "FOO.BAR";
+        };
+        realms = {
+          "FOO.BAR" = {
+            admin_server = "machine";
+            kdc = "machine";
+          };
         };
       };
     };