From c821e0d4be2b4ebc8e1eebca6eb11211a371a43e Mon Sep 17 00:00:00 2001
From: Martin Weinelt <hexa@darmstadt.ccc.de>
Date: Fri, 18 Sep 2020 01:53:52 +0200
Subject: nixos/babeld: lock down service
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→ Overall exposure level for babeld.service: 2.2 OK 🙂
---
 nixos/modules/services/networking/babeld.nix | 34 +++++++++++++++++++++++++---
 1 file changed, 31 insertions(+), 3 deletions(-)

(limited to 'nixos')

diff --git a/nixos/modules/services/networking/babeld.nix b/nixos/modules/services/networking/babeld.nix
index e62c74d0069..90395dbd3c5 100644
--- a/nixos/modules/services/networking/babeld.nix
+++ b/nixos/modules/services/networking/babeld.nix
@@ -87,9 +87,37 @@ in
       description = "Babel routing daemon";
       after = [ "network.target" ];
       wantedBy = [ "multi-user.target" ];
-      serviceConfig.ExecStart = "${pkgs.babeld}/bin/babeld -c ${configFile}";
+      serviceConfig = {
+        ExecStart = "${pkgs.babeld}/bin/babeld -c ${configFile} -I /run/babeld/babeld.pid -S /var/lib/babeld/state";
+        CapabilityBoundingSet = [ "CAP_NET_ADMIN" ];
+        IPAddressAllow = [ "fe80::/64" "ff00::/8" "::1/128" "127.0.0.0/8" ];
+        IPAddressDeny = "any";
+        LockPersonality = true;
+        NoNewPrivileges = true;
+        MemoryDenyWriteExecute = true;
+        ProtectSystem = "strict";
+        ProtectClock = true;
+        ProtectKernelTunables = false; # Couldn't write sysctl: Read-only file system
+        ProtectKernelModules = true;
+        ProtectKernelLogs = true;
+        ProtectControlGroups = true;
+        RestrictAddressFamilies = [ "AF_NETLINK" "AF_INET6" ];
+        RestrictNamespaces = true;
+        RestrictRealtime = true;
+        RestrictSUIDSGID = true;
+        RemoveIPC = true;
+        ProtectHome = true;
+        ProtectHostname = true;
+        PrivateMounts = true;
+        PrivateTmp = true;
+        PrivateDevices = true;
+        PrivateUsers = false; # kernel_route(ADD): Operation not permitted
+        SystemCallArchitectures = "native";
+        SystemCallFilter = [ "@system-service" ];
+        UMask = "0177";
+        RuntimeDirectory = "babeld";
+        StateDirectory = "babeld";
+      };
     };
-
   };
-
 }
-- 
cgit 1.4.1