systemd: adding support for systemd-importd

Adding `systemd-importd` to the build, so that `machinectl`s `import-.*`
may actually do anything. Currently they fail with

```
Failed to transfer image: The name org.freedesktop.import1 was not provided by any .service files
```
as `systemd-importd` is not built. Also registers the regarding dbus
api and service in the systemd module.

nixos/modules/system/boot/systemd.nix

@@ -63,6 +63,7 @@ let
       "systemd-logind.service"
       "autovt@.service"
       "systemd-user-sessions.service"
+      "dbus-org.freedesktop.import1.service"
       "dbus-org.freedesktop.machine1.service"
       "user@.service"
       "user-runtime-dir@.service"
@@ -145,6 +146,7 @@ let
       "user.slice"
       "machine.slice"
       "machines.target"
+      "systemd-importd.service"
       "systemd-machined.service"
       "systemd-nspawn@.service"
 

pkgs/os-specific/linux/systemd/default.nix

@@ -1,5 +1,5 @@
-{ stdenv, lib, fetchFromGitHub, fetchpatch, pkgconfig, intltool, gperf, libcap, kmod
-, xz, pam, acl, libuuid, m4, utillinux, libffi
+{ stdenv, lib, fetchFromGitHub, fetchpatch, pkgconfig, intltool, gperf, libcap
+, curl, kmod, gnupg, gnutar, xz, pam, acl, libuuid, m4, utillinux, libffi
 , glib, kbd, libxslt, coreutils, libgcrypt, libgpgerror, libidn2, libapparmor
 , audit, lz4, bzip2, libmicrohttpd, pcre2
 , linuxHeaders ? stdenv.cc.libc.linuxHeaders
@@ -15,7 +15,21 @@
 , withKexectools ? lib.any (lib.meta.platformMatch stdenv.hostPlatform) kexectools.meta.platforms, kexectools
 }:
 
-stdenv.mkDerivation {
+let gnupg-minimal = gnupg.override {
+  enableMinimal = true;
+  guiSupport = false;
+  pcsclite = null;
+  sqlite = null;
+  pinentry = null;
+  adns = null;
+  gnutls = null;
+  libusb = null;
+  openldap = null;
+  readline = null;
+  zlib = null;
+  bzip2 = null;
+};
+in stdenv.mkDerivation {
   version = "243";
   pname = "systemd";
 
@@ -41,7 +55,7 @@ stdenv.mkDerivation {
       (buildPackages.python3Packages.python.withPackages ( ps: with ps; [ python3Packages.lxml ]))
     ];
   buildInputs =
-    [ linuxHeaders libcap kmod xz pam acl
+    [ linuxHeaders libcap curl.dev kmod xz pam acl
       /* cryptsetup */ libuuid glib libgcrypt libgpgerror libidn2
       libmicrohttpd pcre2 ] ++
       stdenv.lib.optional withKexectools kexectools ++
@@ -67,6 +81,7 @@ stdenv.mkDerivation {
     "-Ddebug-shell=${bashInteractive}/bin/bash"
     # while we do not run tests we should also not build them. Removes about 600 targets
     "-Dtests=false"
+    "-Dimportd=true"
     "-Dlz4=true"
     "-Dhostnamed=true"
     "-Dnetworkd=true"
@@ -77,7 +92,7 @@ stdenv.mkDerivation {
     "-Dlocaled=true"
     "-Dresolve=true"
     "-Dsplit-usr=false"
-    "-Dlibcurl=false"
+    "-Dlibcurl=true"
     "-Dlibidn=false"
     "-Dlibidn2=true"
     "-Dquotacheck=false"
@@ -144,6 +159,14 @@ stdenv.mkDerivation {
       patchShebangs $dir
     done
 
+    # absolute paths to gpg & tar
+    substituteInPlace src/import/pull-common.c \
+      --replace '"gpg"' '"${gnupg-minimal}/bin/gpg"'
+    for file in src/import/{{export,import,pull}-tar,import-common}.c; do
+      substituteInPlace $file \
+        --replace '"tar"' '"${gnutar}/bin/tar"'
+    done
+
     substituteInPlace src/journal/catalog.c \
       --replace /usr/lib/systemd/catalog/ $out/lib/systemd/catalog/
   '';