1{ config, lib, pkgs, ... }:
2
3with lib;
4
5let
6
7 cfg = config.services.atd;
8
9 inherit (pkgs) at;
10
11in
12
13{
14
15 ###### interface
16
17 options = {
18
19 services.atd.enable = mkOption {
20 type = types.bool;
21 default = false;
22 description = ''
23 Whether to enable the <command>at</command> daemon, a command scheduler.
24 '';
25 };
26
27 services.atd.allowEveryone = mkOption {
28 type = types.bool;
29 default = false;
30 description = ''
31 Whether to make <filename>/var/spool/at{jobs,spool}</filename>
32 writeable by everyone (and sticky). This is normally not
33 needed since the <command>at</command> commands are
34 setuid/setgid <literal>atd</literal>.
35 '';
36 };
37
38 };
39
40
41 ###### implementation
42
43 config = mkIf cfg.enable {
44
45 security.setuidOwners = map (program: {
46 inherit program;
47 owner = "atd";
48 group = "atd";
49 setuid = true;
50 setgid = true;
51 }) [ "at" "atq" "atrm" "batch" ];
52
53 environment.systemPackages = [ at ];
54
55 security.pam.services.atd = {};
56
57 users.extraUsers = singleton
58 { name = "atd";
59 uid = config.ids.uids.atd;
60 description = "atd user";
61 home = "/var/empty";
62 };
63
64 users.extraGroups = singleton
65 { name = "atd";
66 gid = config.ids.gids.atd;
67 };
68
69 systemd.services.atd = {
70 description = "Job Execution Daemon (atd)";
71 after = [ "systemd-udev-settle.service" ];
72 wants = [ "systemd-udev-settle.service" ];
73 wantedBy = [ "multi-user.target" ];
74
75 path = [ at ];
76
77 preStart = ''
78 # Snippets taken and adapted from the original `install' rule of
79 # the makefile.
80
81 # We assume these values are those actually used in Nixpkgs for
82 # `at'.
83 spooldir=/var/spool/atspool
84 jobdir=/var/spool/atjobs
85 etcdir=/etc/at
86
87 for dir in "$spooldir" "$jobdir" "$etcdir"; do
88 if [ ! -d "$dir" ]; then
89 mkdir -p "$dir"
90 chown atd:atd "$dir"
91 fi
92 done
93 chmod 1770 "$spooldir" "$jobdir"
94 ${if cfg.allowEveryone then ''chmod a+rwxt "$spooldir" "$jobdir" '' else ""}
95 if [ ! -f "$etcdir"/at.deny ]; then
96 touch "$etcdir"/at.deny
97 chown root:atd "$etcdir"/at.deny
98 chmod 640 "$etcdir"/at.deny
99 fi
100 if [ ! -f "$jobdir"/.SEQ ]; then
101 touch "$jobdir"/.SEQ
102 chown atd:atd "$jobdir"/.SEQ
103 chmod 600 "$jobdir"/.SEQ
104 fi
105 '';
106
107 script = "atd";
108
109 serviceConfig.Type = "forking";
110 };
111 };
112}