nixpkgs/nixos/modules/services/hardware/sane.nix
2019-09-02 23:25:24 +02:00

163 lines
4 KiB
Nix

{ config, lib, pkgs, ... }:
with lib;
let
pkg = if config.hardware.sane.snapshot
then pkgs.sane-backends-git
else pkgs.sane-backends;
sanedConf = pkgs.writeTextFile {
name = "saned.conf";
destination = "/etc/sane.d/saned.conf";
text = ''
localhost
${config.services.saned.extraConfig}
'';
};
netConf = pkgs.writeTextFile {
name = "net.conf";
destination = "/etc/sane.d/net.conf";
text = ''
${lib.optionalString config.services.saned.enable "localhost"}
${config.hardware.sane.netConf}
'';
};
env = {
SANE_CONFIG_DIR = config.hardware.sane.configDir;
LD_LIBRARY_PATH = [ "${saneConfig}/lib/sane" ];
};
backends = [ pkg netConf ] ++ optional config.services.saned.enable sanedConf ++ config.hardware.sane.extraBackends;
saneConfig = pkgs.mkSaneConfig { paths = backends; };
enabled = config.hardware.sane.enable || config.services.saned.enable;
in
{
###### interface
options = {
hardware.sane.enable = mkOption {
type = types.bool;
default = false;
description = ''
Enable support for SANE scanners.
<note><para>
Users in the "scanner" group will gain access to the scanner, or the "lp" group if it's also a printer.
</para></note>
'';
};
hardware.sane.snapshot = mkOption {
type = types.bool;
default = false;
description = "Use a development snapshot of SANE scanner drivers.";
};
hardware.sane.extraBackends = mkOption {
type = types.listOf types.path;
default = [];
description = ''
Packages providing extra SANE backends to enable.
<note><para>
The example contains the package for HP scanners.
</para></note>
'';
example = literalExample "[ pkgs.hplipWithPlugin ]";
};
hardware.sane.configDir = mkOption {
type = types.str;
internal = true;
description = "The value of SANE_CONFIG_DIR.";
};
hardware.sane.netConf = mkOption {
type = types.lines;
default = "";
example = "192.168.0.16";
description = ''
Network hosts that should be probed for remote scanners.
'';
};
services.saned.enable = mkOption {
type = types.bool;
default = false;
description = ''
Enable saned network daemon for remote connection to scanners.
saned would be runned from <literal>scanner</literal> user; to allow
access to hardware that doesn't have <literal>scanner</literal> group
you should add needed groups to this user.
'';
};
services.saned.extraConfig = mkOption {
type = types.lines;
default = "";
example = "192.168.0.0/24";
description = ''
Extra saned configuration lines.
'';
};
};
###### implementation
config = mkMerge [
(mkIf enabled {
hardware.sane.configDir = mkDefault "${saneConfig}/etc/sane.d";
environment.systemPackages = backends;
environment.sessionVariables = env;
services.udev.packages = backends;
users.groups.scanner.gid = config.ids.gids.scanner;
})
(mkIf config.services.saned.enable {
networking.firewall.connectionTrackingModules = [ "sane" ];
systemd.services."saned@" = {
description = "Scanner Service";
environment = mapAttrs (name: val: toString val) env;
serviceConfig = {
User = "scanner";
Group = "scanner";
ExecStart = "${pkg}/bin/saned";
};
};
systemd.sockets.saned = {
description = "saned incoming socket";
wantedBy = [ "sockets.target" ];
listenStreams = [ "0.0.0.0:6566" "[::]:6566" ];
socketConfig = {
# saned needs to distinguish between IPv4 and IPv6 to open matching data sockets.
BindIPv6Only = "ipv6-only";
Accept = true;
MaxConnections = 1;
};
};
users.users.scanner = {
uid = config.ids.uids.scanner;
group = "scanner";
};
})
];
}