From 31b5abf7ec0893320a243e1417a87c08a67a7124 Mon Sep 17 00:00:00 2001
From: clerie <git@clerie.de>
Date: Wed, 13 Jan 2021 13:52:04 +0100
Subject: [PATCH] Transport public net to different location ans source route
 backtraffic via gre

---
 hosts/carbon/configuration.nix     | 80 ++++++++++++++++++++++++++++--
 hosts/gatekeeper/configuration.nix |  2 +-
 2 files changed, 78 insertions(+), 4 deletions(-)

diff --git a/hosts/carbon/configuration.nix b/hosts/carbon/configuration.nix
index cb861ea..31b132d 100644
--- a/hosts/carbon/configuration.nix
+++ b/hosts/carbon/configuration.nix
@@ -32,9 +32,16 @@
     { address = "10.152.0.1"; prefixLength = 32; } # Anycast
   ];
   # Network
+  ## Uplink
   networking.interfaces.enp1s0.useDHCP = true;
-  networking.interfaces.enp2s0.ipv6.addresses = [ { address = "fd00:152:152:4::1"; prefixLength = 64; } ];
-  networking.interfaces.enp2s0.ipv4.addresses = [ { address = "10.152.4.1"; prefixLength = 24; } ];
+  ## Local Network
+  networking.interfaces.enp2s0.ipv6.addresses = [
+    { address = "fd00:152:152:4::1"; prefixLength = 64; }
+    { address = "2a01:4f8:1c0c:8221::1"; prefixLength = 64; } # public IPs for local network
+  ];
+  networking.interfaces.enp2s0.ipv4.addresses = [
+    { address = "10.152.4.1"; prefixLength = 24; }
+  ];
 
   networking.nat = {
     enableIPv6 = true;
@@ -83,15 +90,82 @@
       gre-gatekeeper4 = {
         remote = "10.152.101.1";
         local = (lib.head config.networking.interfaces.lo.ipv4.addresses).address;
-        address = "169.254.201.2/24";
+        address = "10.153.201.2/24";
       };
     };
   };
 
+  # Routing tables
+  # Table: 10000
+  # - primary routes
+  # Table: 11000
+  # - ospf routes
+  # Table: 20101
+  # - default route to gatekeeper
+  #
+  # We will never use main table anymore
+  petabyte.policyrouting = {
+    enable = true;
+    rules6 = [
+      # main routes first except default route
+      { rule = "lookup main suppress_prefixlength 0"; prio = 10000; }
+      # Prefixes defaulting to gatekeeper
+      { rule = "from 2a01:4f8:1c0c:8221::/64 lookup 20101"; prio = 20000; }
+      { rule = "from 2a01:4f8:1c0c:8221::/64 unreachable"; prio = 20001; }
+      # Everything else defaulting to main table after this
+    ];
+    rules4 = [
+      # main routes first except default route
+      { rule = "lookup main suppress_prefixlength 0"; prio = 10000; }
+      # Prefixes defaulting to gatekeeper
+      #{ rule = "from xxx lookup 20101"; prio = 20000; }
+      # Everything else defaulting to main table after this
+    ];
+  };
+
   services.bird2.enable = true;
   services.bird2.config = ''
   router id ${ (lib.head config.networking.interfaces.lo.ipv4.addresses).address };
 
+  ipv6 table gatekeeper6;
+  ipv4 table gatekeeper4;
+
+  protocol static static_gatekeeper_6 {
+          ipv6 {
+                  table gatekeeper6;
+          };
+          route ::/0 via fd00:153:153:201::1;
+  }
+  protocol static static_gatekeeper_4 {
+          ipv4 {
+                  table gatekeeper4;
+          };
+          route 0.0.0.0/0 via 10.153.201.1;
+  }
+
+  protocol kernel kernel_gatekeeper_6 {
+    ipv6 {
+      table gatekeeper6;
+      export filter {
+        krt_prefsrc=${ (lib.head config.networking.interfaces.lo.ipv6.addresses).address };
+        accept;
+      };
+      import none;
+    };
+    kernel table 20101;
+  }
+  protocol kernel kernel_gatekeeper_4 {
+    ipv4 {
+      table gatekeeper4;
+      export filter {
+        krt_prefsrc=${ (lib.head config.networking.interfaces.lo.ipv4.addresses).address };
+        accept;
+      };
+      import none;
+    };
+    kernel table 20101;
+  }
+
   ipv6 table ospf6;
   ipv4 table ospf4;
 
diff --git a/hosts/gatekeeper/configuration.nix b/hosts/gatekeeper/configuration.nix
index af98b74..021e0e5 100644
--- a/hosts/gatekeeper/configuration.nix
+++ b/hosts/gatekeeper/configuration.nix
@@ -135,7 +135,7 @@
       gre-carbon4 = {
         remote = "10.152.104.1";
         local = (lib.head config.networking.interfaces.lo.ipv4.addresses).address;
-        address = "169.254.201.1/24";
+        address = "10.153.201.1/24";
       };
     };
   };