86 lines
2.6 KiB
Nix
86 lines
2.6 KiB
Nix
{ config, lib, ... }:
|
|
|
|
with lib;
|
|
|
|
let
|
|
|
|
sysctlOption = mkOptionType {
|
|
name = "sysctl option value";
|
|
check = val:
|
|
let
|
|
checkType = x: isBool x || isString x || isInt x || x == null;
|
|
in
|
|
checkType val || (val._type or "" == "override" && checkType val.content);
|
|
merge = loc: defs: mergeOneOption loc (filterOverrides defs);
|
|
};
|
|
|
|
in
|
|
|
|
{
|
|
|
|
options = {
|
|
|
|
boot.kernel.sysctl = mkOption {
|
|
type = let
|
|
highestValueType = types.ints.unsigned // {
|
|
merge = loc: defs:
|
|
foldl
|
|
(a: b: if b.value == null then null else lib.max a b.value)
|
|
0
|
|
(filterOverrides defs);
|
|
};
|
|
in types.submodule {
|
|
freeformType = types.attrsOf sysctlOption;
|
|
options = {
|
|
"net.core.rmem_max" = mkOption {
|
|
type = types.nullOr highestValueType;
|
|
default = null;
|
|
description = "The maximum receive socket buffer size in bytes. In case of conflicting values, the highest will be used.";
|
|
};
|
|
|
|
"net.core.wmem_max" = mkOption {
|
|
type = types.nullOr highestValueType;
|
|
default = null;
|
|
description = "The maximum send socket buffer size in bytes. In case of conflicting values, the highest will be used.";
|
|
};
|
|
};
|
|
};
|
|
default = {};
|
|
example = literalExpression ''
|
|
{ "net.ipv4.tcp_syncookies" = false; "vm.swappiness" = 60; }
|
|
'';
|
|
description = ''
|
|
Runtime parameters of the Linux kernel, as set by
|
|
{manpage}`sysctl(8)`. Note that sysctl
|
|
parameters names must be enclosed in quotes
|
|
(e.g. `"vm.swappiness"` instead of
|
|
`vm.swappiness`). The value of each
|
|
parameter may be a string, integer, boolean, or null
|
|
(signifying the option will not appear at all).
|
|
'';
|
|
|
|
};
|
|
|
|
};
|
|
|
|
config = {
|
|
|
|
environment.etc."sysctl.d/60-nixos.conf".text =
|
|
concatStrings (mapAttrsToList (n: v:
|
|
optionalString (v != null) "${n}=${if v == false then "0" else toString v}\n"
|
|
) config.boot.kernel.sysctl);
|
|
|
|
systemd.services.systemd-sysctl =
|
|
{ wantedBy = [ "multi-user.target" ];
|
|
restartTriggers = [ config.environment.etc."sysctl.d/60-nixos.conf".source ];
|
|
};
|
|
|
|
# Hide kernel pointers (e.g. in /proc/modules) for unprivileged
|
|
# users as these make it easier to exploit kernel vulnerabilities.
|
|
boot.kernel.sysctl."kernel.kptr_restrict" = mkDefault 1;
|
|
|
|
# Improve compatibility with applications that allocate
|
|
# a lot of memory, like modern games
|
|
boot.kernel.sysctl."vm.max_map_count" = mkDefault 1048576;
|
|
};
|
|
}
|