nixos/treewide: drop dependencies to keys.target

The `keys.target` is used to indicate whether all NixOps keys were
successfully uploaded on an unattended reboot. However this can cause
startup issues e.g. with NixOS containers (see #67265) and can block
boots even though this might not be needed (e.g. with a dovecot2
instance running that doesn't need any of the NixOps keys).

As described in the NixOps manual[1], dependencies to keys should be
defined like this now:

``` nix
{
  systemd.services.myservice = {
    after = [ "secret-key.service" ];
    wants = [ "secret-key.service" ];
  };
}
```

However I'd leave the issue open until it's discussed whether or not to
keep `keys.target` in `nixpkgs`.

[1] https://nixos.org/nixops/manual/#idm140737322342384

nixos/doc/manual/release-notes/rl-1909.xml

@@ -291,6 +291,26 @@
        configuration while being better type-checked and mergeable.
      </para>
    </listitem>
+   <listitem>
+    <para>
+     No service depends on <literal>keys.target</literal> anymore which is a systemd
+     target that indicates if all <link xlink:href="https://nixos.org/nixops/manual/#idm140737322342384">NixOps keys</link> were successfully uploaded.
+     Instead, <literal>&lt;key-name&gt;-key.service</literal> should be used to define
+     a dependency of a key in a service. The full issue behind the <literal>keys.target</literal>
+     dependency is described at <link xlink:href="https://github.com/NixOS/nixpkgs/issues/67265">NixOS/nixpkgs#67265</link>.
+    </para>
+    <para>
+     The following services are affected by this:
+     <itemizedlist>
+      <listitem><para><link linkend="opt-services.dovecot2.enable"><literal>services.dovecot2</literal></link></para></listitem>
+      <listitem><para><link linkend="opt-services.nsd.enable"><literal>services.nsd</literal></link></para></listitem>
+      <listitem><para><link linkend="opt-services.softether.enable"><literal>services.softether</literal></link></para></listitem>
+      <listitem><para><link linkend="opt-services.strongswan.enable"><literal>services.strongswan</literal></link></para></listitem>
+      <listitem><para><link linkend="opt-services.strongswan-swanctl.enable"><literal>services.strongswan-swanctl</literal></link></para></listitem>
+      <listitem><para><link linkend="opt-services.httpd.enable"><literal>services.httpd</literal></link></para></listitem>
+     </itemizedlist>
+    </para>
+   </listitem>
   </itemizedlist>
  </section>
 

nixos/modules/services/mail/dovecot.nix

@@ -344,8 +344,7 @@ in
     systemd.services.dovecot2 = {
       description = "Dovecot IMAP/POP3 server";
 
-      after = [ "keys.target" "network.target" ];
+      after = [ "network.target" ];
-      wants = [ "keys.target" ];
       wantedBy = [ "multi-user.target" ];
       restartTriggers = [ cfg.configFile ];
 

nixos/modules/services/networking/nsd.nix

@@ -916,9 +916,8 @@ in
     systemd.services.nsd = {
       description = "NSD authoritative only domain name service";
 
-      after = [ "keys.target" "network.target" ];
+      after = [ "network.target" ];
       wantedBy = [ "multi-user.target" ];
-      wants = [ "keys.target" ];
 
       serviceConfig = {
         ExecStart = "${nsdPkg}/sbin/nsd -d -c ${nsdEnv}/nsd.conf";

nixos/modules/services/networking/softether.nix

@@ -70,8 +70,6 @@ in
 
       systemd.services."softether-init" = {
         description = "SoftEther VPN services initial task";
-        after = [ "keys.target" ];
-        wants = [ "keys.target" ];
         wantedBy = [ "network.target" ];
         serviceConfig = {
           Type = "oneshot";

nixos/modules/services/networking/strongswan-swanctl/module.nix

@@ -62,9 +62,8 @@ in  {
     systemd.services.strongswan-swanctl = {
       description = "strongSwan IPsec IKEv1/IKEv2 daemon using swanctl";
       wantedBy = [ "multi-user.target" ];
-      after    = [ "network-online.target" "keys.target" ];
+      after    = [ "network-online.target" ];
-      wants    = [ "keys.target" ];
+      path     = with pkgs; [ kmod iproute iptables utillinux ];
-      path = with pkgs; [ kmod iproute iptables utillinux ];
       environment = {
         STRONGSWAN_CONF = pkgs.writeTextFile {
           name = "strongswan.conf";

nixos/modules/services/networking/strongswan.nix

@@ -151,8 +151,7 @@ in
       description = "strongSwan IPSec Service";
       wantedBy = [ "multi-user.target" ];
       path = with pkgs; [ kmod iproute iptables utillinux ]; # XXX Linux
-      wants = [ "keys.target" ];
+      after = [ "network-online.target" ];
-      after = [ "network-online.target" "keys.target" ];
       environment = {
         STRONGSWAN_CONF = strongswanConf { inherit setup connections ca secretsFile managePlugins enabledPlugins; };
       };

nixos/modules/services/web-servers/apache-httpd/default.nix

@@ -670,8 +670,7 @@ in
       { description = "Apache HTTPD";
 
         wantedBy = [ "multi-user.target" ];
-        wants = [ "keys.target" ];
+        after = [ "network.target" "fs.target" ];
-        after = [ "network.target" "fs.target" "keys.target" ];
 
         path =
           [ httpd pkgs.coreutils pkgs.gnugrep ]