nixpkgs/nixos/modules/services/networking/libreswan.nix
2022-12-17 19:31:14 -05:00

161 lines
4.4 KiB
Nix

{ config, lib, pkgs, ... }:
with lib;
let
cfg = config.services.libreswan;
libexec = "${pkgs.libreswan}/libexec/ipsec";
ipsec = "${pkgs.libreswan}/sbin/ipsec";
trim = chars: str:
let
nonchars = filter (x : !(elem x.value chars))
(imap0 (i: v: {ind = i; value = v;}) (stringToCharacters str));
in
if length nonchars == 0 then ""
else substring (head nonchars).ind (add 1 (sub (last nonchars).ind (head nonchars).ind)) str;
indent = str: concatStrings (concatMap (s: [" " (trim [" " "\t"] s) "\n"]) (splitString "\n" str));
configText = indent (toString cfg.configSetup);
connectionText = concatStrings (mapAttrsToList (n: v:
''
conn ${n}
${indent v}
'') cfg.connections);
configFile = pkgs.writeText "ipsec-nixos.conf"
''
config setup
${configText}
${connectionText}
'';
policyFiles = mapAttrs' (name: text:
{ name = "ipsec.d/policies/${name}";
value.source = pkgs.writeText "ipsec-policy-${name}" text;
}) cfg.policies;
in
{
###### interface
options = {
services.libreswan = {
enable = mkEnableOption (lib.mdDoc "Libreswan IPsec service");
configSetup = mkOption {
type = types.lines;
default = ''
protostack=netkey
virtual_private=%v4:10.0.0.0/8,%v4:192.168.0.0/16,%v4:172.16.0.0/12,%v4:25.0.0.0/8,%v4:100.64.0.0/10,%v6:fd00::/8,%v6:fe80::/10
'';
example = ''
secretsfile=/root/ipsec.secrets
protostack=netkey
virtual_private=%v4:10.0.0.0/8,%v4:192.168.0.0/16,%v4:172.16.0.0/12,%v4:25.0.0.0/8,%v4:100.64.0.0/10,%v6:fd00::/8,%v6:fe80::/10
'';
description = lib.mdDoc "Options to go in the 'config setup' section of the Libreswan IPsec configuration";
};
connections = mkOption {
type = types.attrsOf types.lines;
default = {};
example = literalExpression ''
{ myconnection = '''
auto=add
left=%defaultroute
leftid=@user
right=my.vpn.com
ikev2=no
ikelifetime=8h
''';
}
'';
description = lib.mdDoc "A set of connections to define for the Libreswan IPsec service";
};
policies = mkOption {
type = types.attrsOf types.lines;
default = {};
example = literalExpression ''
{ private-or-clear = '''
# Attempt opportunistic IPsec for the entire Internet
0.0.0.0/0
::/0
''';
}
'';
description = lib.mdDoc ''
A set of policies to apply to the IPsec connections.
::: {.note}
The policy name must match the one of connection it needs to apply to.
:::
'';
};
disableRedirects = mkOption {
type = types.bool;
default = true;
description = lib.mdDoc ''
Whether to disable send and accept redirects for all network interfaces.
See the Libreswan [
FAQ](https://libreswan.org/wiki/FAQ#Why_is_it_recommended_to_disable_send_redirects_in_.2Fproc.2Fsys.2Fnet_.3F) page for why this is recommended.
'';
};
};
};
###### implementation
config = mkIf cfg.enable {
# Install package, systemd units, etc.
environment.systemPackages = [ pkgs.libreswan pkgs.iproute2 ];
systemd.packages = [ pkgs.libreswan ];
systemd.tmpfiles.packages = [ pkgs.libreswan ];
# Install configuration files
environment.etc = {
"ipsec.secrets".source = "${pkgs.libreswan}/etc/ipsec.secrets";
"ipsec.conf".source = "${pkgs.libreswan}/etc/ipsec.conf";
"ipsec.d/01-nixos.conf".source = configFile;
} // policyFiles;
# Create NSS database directory
systemd.tmpfiles.rules = [ "d /var/lib/ipsec/nss 755 root root -" ];
systemd.services.ipsec = {
description = "Internet Key Exchange (IKE) Protocol Daemon for IPsec";
wantedBy = [ "multi-user.target" ];
restartTriggers = [ configFile ] ++ mapAttrsToList (n: v: v.source) policyFiles;
path = with pkgs; [
libreswan
iproute2
procps
nssTools
iptables
nettools
];
preStart = optionalString cfg.disableRedirects ''
# Disable send/receive redirects
echo 0 | tee /proc/sys/net/ipv4/conf/*/send_redirects
echo 0 | tee /proc/sys/net/ipv{4,6}/conf/*/accept_redirects
'';
};
};
}