google-compute-config.nix: use sysctl snippets from gce

We make them available at ${gce}/sysctl.d and add them to
environments.etc, like we do with the systemd ones.

2 files changed, 5 insertions, 77 deletions

diff --git a/nixos/modules/virtualisation/google-compute-config.nix b/nixos/modules/virtualisation/google-compute-config.nix
index 41fbf4702e8..327324f2921 100644
--- a/nixos/modules/virtualisation/google-compute-config.nix
+++ b/nixos/modules/virtualisation/google-compute-config.nix
@@ -144,81 +144,5 @@ in
     wantedBy = [ "multi-user.target" ];
   };
 
-
-  # Settings taken from https://github.com/GoogleCloudPlatform/compute-image-packages/blob/master/google_config/sysctl/11-gce-network-security.conf
-  boot.kernel.sysctl = {
-    # Turn on SYN-flood protections.  Starting with 2.6.26, there is no loss
-    # of TCP functionality/features under normal conditions.  When flood
-    # protections kick in under high unanswered-SYN load, the system
-    # should remain more stable, with a trade off of some loss of TCP
-    # functionality/features (e.g. TCP Window scaling).
-    "net.ipv4.tcp_syncookies" = mkDefault "1";
-
-    # ignores ICMP redirects
-    "net.ipv4.conf.all.accept_redirects" = mkDefault "0";
-
-    # ignores ICMP redirects
-    "net.ipv4.conf.default.accept_redirects" = mkDefault "0";
-
-    # ignores ICMP redirects from non-GW hosts
-    "net.ipv4.conf.all.secure_redirects" = mkDefault "1";
-
-    # ignores ICMP redirects from non-GW hosts
-    "net.ipv4.conf.default.secure_redirects" = mkDefault "1";
-
-    # don't allow traffic between networks or act as a router
-    "net.ipv4.ip_forward" = mkDefault "0";
-
-    # don't allow traffic between networks or act as a router
-    "net.ipv4.conf.all.send_redirects" = mkDefault "0";
-
-    # don't allow traffic between networks or act as a router
-    "net.ipv4.conf.default.send_redirects" = mkDefault "0";
-
-    # strict reverse path filtering - IP spoofing protection
-    "net.ipv4.conf.all.rp_filter" = mkDefault "1";
-
-    # strict path filtering - IP spoofing protection
-    "net.ipv4.conf.default.rp_filter" = mkDefault "1";
-
-    # ignores ICMP broadcasts to avoid participating in Smurf attacks
-    "net.ipv4.icmp_echo_ignore_broadcasts" = mkDefault "1";
-
-    # ignores bad ICMP errors
-    "net.ipv4.icmp_ignore_bogus_error_responses" = mkDefault "1";
-
-    # logs spoofed, source-routed, and redirect packets
-    "net.ipv4.conf.all.log_martians" = mkDefault "1";
-
-    # log spoofed, source-routed, and redirect packets
-    "net.ipv4.conf.default.log_martians" = mkDefault "1";
-
-    # implements RFC 1337 fix
-    "net.ipv4.tcp_rfc1337" = mkDefault "1";
-
-    # randomizes addresses of mmap base, heap, stack and VDSO page
-    "kernel.randomize_va_space" = mkDefault "2";
-
-    # Reboot the machine soon after a kernel panic.
-    "kernel.panic" = mkDefault "10";
-
-    ## Not part of the original config
-
-    # provides protection from ToCToU races
-    "fs.protected_hardlinks" = mkDefault "1";
-
-    # provides protection from ToCToU races
-    "fs.protected_symlinks" = mkDefault "1";
-
-    # makes locating kernel addresses more difficult
-    "kernel.kptr_restrict" = mkDefault "1";
-
-    # set ptrace protections
-    "kernel.yama.ptrace_scope" = mkOverride 500 "1";
-
-    # set perf only available to root
-    "kernel.perf_event_paranoid" = mkDefault "2";
-
-  };
-
+  environment.etc."sysctl.d/11-gce-network-security.conf".source = "${gce}/sysctl.d/11-gce-network-security.conf";
 }
diff --git a/pkgs/tools/virtualization/google-compute-engine/default.nix b/pkgs/tools/virtualization/google-compute-engine/default.nix
index d4c817b7ecb..48255ca68a7 100644
--- a/pkgs/tools/virtualization/google-compute-engine/default.nix
+++ b/pkgs/tools/virtualization/google-compute-engine/default.nix
@@ -46,6 +46,10 @@ buildPythonApplication rec {
     mkdir -p $out/lib/udev/rules.d
     cp -r google_config/udev/*.rules $out/lib/udev/rules.d
 
+    # sysctl snippets will be used by google-compute-config.nix
+    mkdir -p $out/sysctl.d
+    cp google_config/sysctl/*.conf $out/sysctl.d
+
     patchShebangs $out/bin/*
   '';