diff options
Diffstat (limited to 'nixos/modules/services/security/haveged.nix')
-rw-r--r-- | nixos/modules/services/security/haveged.nix | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/nixos/modules/services/security/haveged.nix b/nixos/modules/services/security/haveged.nix new file mode 100644 index 00000000000..57cef7e44d5 --- /dev/null +++ b/nixos/modules/services/security/haveged.nix @@ -0,0 +1,77 @@ +{ config, lib, pkgs, ... }: + +with lib; + +let + cfg = config.services.haveged; + +in + +{ + + ###### interface + + options = { + + services.haveged = { + + enable = mkEnableOption '' + haveged entropy daemon, which refills /dev/random when low. + NOTE: does nothing on kernels newer than 5.6. + ''; + # source for the note https://github.com/jirka-h/haveged/issues/57 + + refill_threshold = mkOption { + type = types.int; + default = 1024; + description = '' + The number of bits of available entropy beneath which + haveged should refill the entropy pool. + ''; + }; + + }; + + }; + + config = mkIf cfg.enable { + + # https://github.com/jirka-h/haveged/blob/a4b69d65a8dfc5a9f52ff8505c7f58dcf8b9234f/contrib/Fedora/haveged.service + systemd.services.haveged = { + description = "Entropy Daemon based on the HAVEGE algorithm"; + unitConfig = { + Documentation = "man:haveged(8)"; + DefaultDependencies = false; + ConditionKernelVersion = "<5.6"; + }; + wantedBy = [ "sysinit.target" ]; + after = [ "systemd-tmpfiles-setup-dev.service" ]; + before = [ "sysinit.target" "shutdown.target" "systemd-journald.service" ]; + + serviceConfig = { + ExecStart = "${pkgs.haveged}/bin/haveged -w ${toString cfg.refill_threshold} --Foreground -v 1"; + Restart = "always"; + SuccessExitStatus = "137 143"; + SecureBits = "noroot-locked"; + CapabilityBoundingSet = [ "CAP_SYS_ADMIN" "CAP_SYS_CHROOT" ]; + # We can *not* set PrivateTmp=true as it can cause an ordering cycle. + PrivateTmp = false; + PrivateDevices = true; + ProtectSystem = "full"; + ProtectHome = true; + ProtectHostname = true; + ProtectKernelLogs = true; + ProtectKernelModules = true; + RestrictNamespaces = true; + RestrictRealtime = true; + LockPersonality = true; + MemoryDenyWriteExecute = true; + SystemCallArchitectures = "native"; + SystemCallFilter = [ "@system-service" "newuname" "~@mount" ]; + SystemCallErrorNumber = "EPERM"; + }; + + }; + }; + +} |