tv: modularize iptables configuration

11 files changed, 193 insertions, 301 deletions

diff --git a/modules/cd/default.nix b/modules/cd/default.nix
index 6884c67f..21d9565f 100644
--- a/modules/cd/default.nix
+++ b/modules/cd/default.nix
@@ -8,7 +8,6 @@ in
   imports =
     [
       <secrets/hashedPasswords.nix>
-      ./iptables.nix
       ./networking.nix
       ./users.nix
       ../common/nixpkgs.nix
@@ -19,6 +18,22 @@ in
       ../tv/git/public.nix
       ../tv/retiolum.nix
       ../tv/sanitize.nix
+      {
+        imports = [ ../tv/iptables ];
+        tv.iptables = {
+          enable = true;
+          input-internet-accept-new-tcp = [
+            "ssh"
+            "tinc"
+            "smtp"
+            "xmpp-client"
+            "xmpp-server"
+          ];
+          input-retiolum-accept-new-tcp = [
+            "http"
+          ];
+        };
+      }
     ];
 
   # "Developer 2" plan has two vCPUs.
diff --git a/modules/cd/iptables.nix b/modules/cd/iptables.nix
deleted file mode 100644
index 950aa847..00000000
--- a/modules/cd/iptables.nix
+++ /dev/null
@@ -1,76 +0,0 @@
-{ config, pkgs, ... }:
-
-{
-  #
-  # iptables
-  #
-  networking.firewall.enable = false;
-  system.activationScripts.iptables =
-    let
-      log = false;
-      when = c: f: if c then f else "";
-    in
-      ''
-        ip4tables() { ${pkgs.iptables}/sbin/iptables "$@"; }
-        ip6tables() { ${pkgs.iptables}/sbin/ip6tables "$@"; }
-        ipXtables() { ip4tables "$@" && ip6tables "$@"; }
-
-        # XXX This fails with the original CAC CentOS 7 kernel.
-        if ipXtables -vL >/dev/null; then
-
-          #
-          # nat
-          #
-
-          # reset tables
-          ipXtables -t nat -F
-          ipXtables -t nat -X
-
-          #
-          ipXtables -t nat -A PREROUTING -j REDIRECT ! -i retiolum -p tcp --dport ssh --to-ports 0
-          ipXtables -t nat -A PREROUTING -j REDIRECT -p tcp --dport 11423 --to-ports ssh
-
-          #
-          # filter
-          #
-
-          # reset tables
-          ipXtables -P INPUT DROP
-          ipXtables -P FORWARD DROP
-          ipXtables -F
-          ipXtables -X
-
-          # create custom chains
-          ipXtables -N Retiolum
-
-          # INPUT
-          ipXtables -A INPUT -j ACCEPT -m conntrack --ctstate RELATED,ESTABLISHED
-          ipXtables -A INPUT -j ACCEPT -i lo
-          ipXtables -A INPUT -j ACCEPT -p tcp --dport ssh -m conntrack --ctstate NEW
-          #ipXtables -A INPUT -j ACCEPT -p tcp --dport http -m conntrack --ctstate NEW
-          ipXtables -A INPUT -j ACCEPT -p tcp --dport tinc -m conntrack --ctstate NEW
-          ipXtables -A INPUT -j ACCEPT -p tcp --dport smtp -m conntrack --ctstate NEW
-          ipXtables -A INPUT -j ACCEPT -p tcp --dport xmpp-client -m conntrack --ctstate NEW
-          ipXtables -A INPUT -j ACCEPT -p tcp --dport xmpp-server -m conntrack --ctstate NEW
-
-          ipXtables -A INPUT -j Retiolum -i retiolum
-          ${when log "ipXtables -A INPUT -j LOG --log-level info --log-prefix 'INPUT DROP '"}
-
-          # FORWARD
-          ${when log "ipXtables -A FORWARD -j LOG --log-level info --log-prefix 'FORWARD DROP '"}
-
-          # Retiolum
-          ip4tables -A Retiolum -j ACCEPT -p icmp --icmp-type echo-request
-          ip6tables -A Retiolum -j ACCEPT -p ipv6-icmp -m icmp6 --icmpv6-type echo-request
-
-          ipXtables -A Retiolum -j ACCEPT -p tcp --dport http -m conntrack --ctstate NEW
-
-          ${when log "ipXtables -A Retiolum -j LOG --log-level info --log-prefix 'REJECT '"}
-          ipXtables -A Retiolum -j REJECT -p tcp --reject-with tcp-reset
-          ip4tables -A Retiolum -j REJECT -p udp --reject-with icmp-port-unreachable
-          ip4tables -A Retiolum -j REJECT        --reject-with icmp-proto-unreachable
-          ip6tables -A Retiolum -j REJECT -p udp --reject-with icmp6-port-unreachable
-          ip6tables -A Retiolum -j REJECT
-        fi
-      '';
-}
diff --git a/modules/mkdir/default.nix b/modules/mkdir/default.nix
index d5257977..9dc426df 100644
--- a/modules/mkdir/default.nix
+++ b/modules/mkdir/default.nix
@@ -8,7 +8,6 @@ in
   imports =
     [
       <secrets/hashedPasswords.nix>
-      ./iptables.nix
       ./networking.nix
       ./users.nix
       ../common/nixpkgs.nix
@@ -18,6 +17,22 @@ in
       ../tv/git/public.nix
       ../tv/retiolum.nix
       ../tv/sanitize.nix
+      {
+        imports = [ ../tv/iptables ];
+        tv.iptables = {
+          enable = true;
+          input-internet-accept-new-tcp = [
+            "ssh"
+            "tinc"
+            "smtp"
+            "xmpp-client"
+            "xmpp-server"
+          ];
+          input-retiolum-accept-new-tcp = [
+            "http"
+          ];
+        };
+      }
     ];
 
   nix.maxJobs = 1;
diff --git a/modules/mkdir/iptables.nix b/modules/mkdir/iptables.nix
deleted file mode 100644
index 950aa847..00000000
--- a/modules/mkdir/iptables.nix
+++ /dev/null
@@ -1,76 +0,0 @@
-{ config, pkgs, ... }:
-
-{
-  #
-  # iptables
-  #
-  networking.firewall.enable = false;
-  system.activationScripts.iptables =
-    let
-      log = false;
-      when = c: f: if c then f else "";
-    in
-      ''
-        ip4tables() { ${pkgs.iptables}/sbin/iptables "$@"; }
-        ip6tables() { ${pkgs.iptables}/sbin/ip6tables "$@"; }
-        ipXtables() { ip4tables "$@" && ip6tables "$@"; }
-
-        # XXX This fails with the original CAC CentOS 7 kernel.
-        if ipXtables -vL >/dev/null; then
-
-          #
-          # nat
-          #
-
-          # reset tables
-          ipXtables -t nat -F
-          ipXtables -t nat -X
-
-          #
-          ipXtables -t nat -A PREROUTING -j REDIRECT ! -i retiolum -p tcp --dport ssh --to-ports 0
-          ipXtables -t nat -A PREROUTING -j REDIRECT -p tcp --dport 11423 --to-ports ssh
-
-          #
-          # filter
-          #
-
-          # reset tables
-          ipXtables -P INPUT DROP
-          ipXtables -P FORWARD DROP
-          ipXtables -F
-          ipXtables -X
-
-          # create custom chains
-          ipXtables -N Retiolum
-
-          # INPUT
-          ipXtables -A INPUT -j ACCEPT -m conntrack --ctstate RELATED,ESTABLISHED
-          ipXtables -A INPUT -j ACCEPT -i lo
-          ipXtables -A INPUT -j ACCEPT -p tcp --dport ssh -m conntrack --ctstate NEW
-          #ipXtables -A INPUT -j ACCEPT -p tcp --dport http -m conntrack --ctstate NEW
-          ipXtables -A INPUT -j ACCEPT -p tcp --dport tinc -m conntrack --ctstate NEW
-          ipXtables -A INPUT -j ACCEPT -p tcp --dport smtp -m conntrack --ctstate NEW
-          ipXtables -A INPUT -j ACCEPT -p tcp --dport xmpp-client -m conntrack --ctstate NEW
-          ipXtables -A INPUT -j ACCEPT -p tcp --dport xmpp-server -m conntrack --ctstate NEW
-
-          ipXtables -A INPUT -j Retiolum -i retiolum
-          ${when log "ipXtables -A INPUT -j LOG --log-level info --log-prefix 'INPUT DROP '"}
-
-          # FORWARD
-          ${when log "ipXtables -A FORWARD -j LOG --log-level info --log-prefix 'FORWARD DROP '"}
-
-          # Retiolum
-          ip4tables -A Retiolum -j ACCEPT -p icmp --icmp-type echo-request
-          ip6tables -A Retiolum -j ACCEPT -p ipv6-icmp -m icmp6 --icmpv6-type echo-request
-
-          ipXtables -A Retiolum -j ACCEPT -p tcp --dport http -m conntrack --ctstate NEW
-
-          ${when log "ipXtables -A Retiolum -j LOG --log-level info --log-prefix 'REJECT '"}
-          ipXtables -A Retiolum -j REJECT -p tcp --reject-with tcp-reset
-          ip4tables -A Retiolum -j REJECT -p udp --reject-with icmp-port-unreachable
-          ip4tables -A Retiolum -j REJECT        --reject-with icmp-proto-unreachable
-          ip6tables -A Retiolum -j REJECT -p udp --reject-with icmp6-port-unreachable
-          ip6tables -A Retiolum -j REJECT
-        fi
-      '';
-}
diff --git a/modules/rmdir/default.nix b/modules/rmdir/default.nix
index e514e5da..9879fadf 100644
--- a/modules/rmdir/default.nix
+++ b/modules/rmdir/default.nix
@@ -8,7 +8,6 @@ in
   imports =
     [
       <secrets/hashedPasswords.nix>
-      ./iptables.nix
       ./networking.nix
       ./users.nix
       ../common/nixpkgs.nix
@@ -18,6 +17,22 @@ in
       ../tv/git/public.nix
       ../tv/retiolum.nix
       ../tv/sanitize.nix
+      {
+        imports = [ ../tv/iptables ];
+        tv.iptables = {
+          enable = true;
+          input-internet-accept-new-tcp = [
+            "ssh"
+            "tinc"
+            "smtp"
+            "xmpp-client"
+            "xmpp-server"
+          ];
+          input-retiolum-accept-new-tcp = [
+            "http"
+          ];
+        };
+      }
     ];
 
   nix.maxJobs = 1;
diff --git a/modules/rmdir/iptables.nix b/modules/rmdir/iptables.nix
deleted file mode 100644
index 950aa847..00000000
--- a/modules/rmdir/iptables.nix
+++ /dev/null
@@ -1,76 +0,0 @@
-{ config, pkgs, ... }:
-
-{
-  #
-  # iptables
-  #
-  networking.firewall.enable = false;
-  system.activationScripts.iptables =
-    let
-      log = false;
-      when = c: f: if c then f else "";
-    in
-      ''
-        ip4tables() { ${pkgs.iptables}/sbin/iptables "$@"; }
-        ip6tables() { ${pkgs.iptables}/sbin/ip6tables "$@"; }
-        ipXtables() { ip4tables "$@" && ip6tables "$@"; }
-
-        # XXX This fails with the original CAC CentOS 7 kernel.
-        if ipXtables -vL >/dev/null; then
-
-          #
-          # nat
-          #
-
-          # reset tables
-          ipXtables -t nat -F
-          ipXtables -t nat -X
-
-          #
-          ipXtables -t nat -A PREROUTING -j REDIRECT ! -i retiolum -p tcp --dport ssh --to-ports 0
-          ipXtables -t nat -A PREROUTING -j REDIRECT -p tcp --dport 11423 --to-ports ssh
-
-          #
-          # filter
-          #
-
-          # reset tables
-          ipXtables -P INPUT DROP
-          ipXtables -P FORWARD DROP
-          ipXtables -F
-          ipXtables -X
-
-          # create custom chains
-          ipXtables -N Retiolum
-
-          # INPUT
-          ipXtables -A INPUT -j ACCEPT -m conntrack --ctstate RELATED,ESTABLISHED
-          ipXtables -A INPUT -j ACCEPT -i lo
-          ipXtables -A INPUT -j ACCEPT -p tcp --dport ssh -m conntrack --ctstate NEW
-          #ipXtables -A INPUT -j ACCEPT -p tcp --dport http -m conntrack --ctstate NEW
-          ipXtables -A INPUT -j ACCEPT -p tcp --dport tinc -m conntrack --ctstate NEW
-          ipXtables -A INPUT -j ACCEPT -p tcp --dport smtp -m conntrack --ctstate NEW
-          ipXtables -A INPUT -j ACCEPT -p tcp --dport xmpp-client -m conntrack --ctstate NEW
-          ipXtables -A INPUT -j ACCEPT -p tcp --dport xmpp-server -m conntrack --ctstate NEW
-
-          ipXtables -A INPUT -j Retiolum -i retiolum
-          ${when log "ipXtables -A INPUT -j LOG --log-level info --log-prefix 'INPUT DROP '"}
-
-          # FORWARD
-          ${when log "ipXtables -A FORWARD -j LOG --log-level info --log-prefix 'FORWARD DROP '"}
-
-          # Retiolum
-          ip4tables -A Retiolum -j ACCEPT -p icmp --icmp-type echo-request
-          ip6tables -A Retiolum -j ACCEPT -p ipv6-icmp -m icmp6 --icmpv6-type echo-request
-
-          ipXtables -A Retiolum -j ACCEPT -p tcp --dport http -m conntrack --ctstate NEW
-
-          ${when log "ipXtables -A Retiolum -j LOG --log-level info --log-prefix 'REJECT '"}
-          ipXtables -A Retiolum -j REJECT -p tcp --reject-with tcp-reset
-          ip4tables -A Retiolum -j REJECT -p udp --reject-with icmp-port-unreachable
-          ip4tables -A Retiolum -j REJECT        --reject-with icmp-proto-unreachable
-          ip6tables -A Retiolum -j REJECT -p udp --reject-with icmp6-port-unreachable
-          ip6tables -A Retiolum -j REJECT
-        fi
-      '';
-}
diff --git a/modules/tv/iptables/config.nix b/modules/tv/iptables/config.nix
new file mode 100644
index 00000000..a525cfa5
--- /dev/null
+++ b/modules/tv/iptables/config.nix
@@ -0,0 +1,93 @@
+{ cfg, lib, pkgs, ... }:
+
+let
+  inherit (pkgs) writeScript writeText;
+  inherit (lib) concatMapStringsSep;
+
+  accept-new-tcp = port:
+    "-p tcp -m tcp --dport ${port} -m conntrack --ctstate NEW -j ACCEPT";
+
+  rules = iptables-version:
+    writeText "tv-iptables-rules${toString iptables-version}" ''
+      *nat
+      :PREROUTING ACCEPT [0:0]
+      :INPUT ACCEPT [0:0]
+      :OUTPUT ACCEPT [0:0]
+      :POSTROUTING ACCEPT [0:0]
+      ${concatMapStringsSep "\n" (rule: "-A PREROUTING ${rule}") ([]
+        ++ [
+          "! -i retiolum -p tcp -m tcp --dport 22 -j REDIRECT --to-ports 0"
+          "-p tcp -m tcp --dport 11423 -j REDIRECT --to-ports 22"
+        ]
+      )}
+      COMMIT
+      *filter
+      :INPUT DROP [0:0]
+      :FORWARD DROP [0:0]
+      :OUTPUT ACCEPT [0:0]
+      :Retiolum - [0:0]
+      ${concatMapStringsSep "\n" (rule: "-A INPUT ${rule}") ([]
+        ++ [
+          "-m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT"
+          "-i lo -j ACCEPT"
+        ]
+        ++ map accept-new-tcp cfg.input-internet-accept-new-tcp
+        ++ ["-i retiolum -j Retiolum"]
+      )}
+      ${concatMapStringsSep "\n" (rule: "-A Retiolum ${rule}") ([]
+        ++ {
+          ip4tables = [
+            "-p icmp -m icmp --icmp-type echo-request -j ACCEPT"
+          ];
+          ip6tables = [
+            "-p ipv6-icmp -m icmp6 --icmpv6-type echo-request -j ACCEPT"
+          ];
+        }."ip${toString iptables-version}tables"
+        ++ map accept-new-tcp cfg.input-retiolum-accept-new-tcp
+        ++ {
+          ip4tables = [
+            "-p tcp -j REJECT --reject-with tcp-reset"
+            "-p udp -j REJECT --reject-with icmp-port-unreachable"
+            "-j REJECT --reject-with icmp-proto-unreachable"
+          ];
+          ip6tables = [
+            "-p tcp -j REJECT --reject-with tcp-reset"
+            "-p udp -j REJECT --reject-with icmp6-port-unreachable"
+            "-j REJECT"
+          ];
+        }."ip${toString iptables-version}tables"
+      )}
+      COMMIT
+    '';
+
+  startScript = writeScript "tv-iptables_start" ''
+    #! /bin/sh
+    set -euf
+    iptables-restore < ${rules 4}
+    ip6tables-restore < ${rules 6}
+  '';
+in
+
+{
+  networking.firewall.enable = false;
+
+  systemd.services.tv-iptables = {
+    description = "tv-iptables";
+    wantedBy = [ "network-pre.target" ];
+    before = [ "network-pre.target" ];
+    after = [ "systemd-modules-load.service" ];
+
+    path = with pkgs; [
+      iptables
+    ];
+    
+    restartIfChanged = true;
+    
+    serviceConfig = {
+      Type = "simple";
+      RemainAfterExit = true;
+      Restart = "always";
+      ExecStart = "@${startScript} tv-iptables_start";
+    };
+  };
+}
diff --git a/modules/tv/iptables/default.nix b/modules/tv/iptables/default.nix
new file mode 100644
index 00000000..cf27a26a
--- /dev/null
+++ b/modules/tv/iptables/default.nix
@@ -0,0 +1,11 @@
+arg@{ config, lib, pkgs, ... }:
+
+let
+  cfg = config.tv.iptables;
+  arg' = arg // { inherit cfg; };
+in
+
+{
+  options.tv.iptables = import ./options.nix arg';
+  config = lib.mkIf cfg.enable (import ./config.nix arg');
+}
diff --git a/modules/tv/iptables/options.nix b/modules/tv/iptables/options.nix
new file mode 100644
index 00000000..79be1d08
--- /dev/null
+++ b/modules/tv/iptables/options.nix
@@ -0,0 +1,29 @@
+{ lib, ... }:
+
+let
+  inherit (lib) mkOption types;
+in
+
+{
+  enable = mkOption {
+    type = types.bool;
+    default = false;
+    description = "Enable iptables.";
+  };
+
+  input-internet-accept-new-tcp = mkOption {
+    type = with types; listOf str;
+    default = [];
+    description = ''
+      ip{4,6}tables -A INPUT -j ACCEPT -p tcp --dport $port -m conntrack --ctstate NEW
+    '';
+  };
+
+  input-retiolum-accept-new-tcp = mkOption {
+    type = with types; listOf str;
+    default = [];
+    description = ''
+      ip{4,6}tables -A Retiolum -j ACCEPT -p tcp --dport $port -m conntrack --ctstate NEW
+    '';
+  };
+}
diff --git a/modules/wu/default.nix b/modules/wu/default.nix
index 68475ad5..76e8c6bb 100644
--- a/modules/wu/default.nix
+++ b/modules/wu/default.nix
@@ -9,7 +9,6 @@ in
 {
   imports = [
     ./hosts.nix
-    ./iptables.nix
     ../common/nixpkgs.nix
     ../tv/base.nix
     ../tv/exim-retiolum.nix
@@ -22,6 +21,18 @@ in
     ../tv/urxvt.nix
     ../tv/xserver.nix
     ../wu/users.nix
+    {
+      imports = [ ../tv/iptables ];
+      tv.iptables = {
+        enable = true;
+        input-internet-accept-new-tcp = [
+          "ssh"
+          "http"
+          "tinc"
+          "smtp"
+        ];
+      };
+    }
   ];
 
   nix.maxJobs = 8;
diff --git a/modules/wu/iptables.nix b/modules/wu/iptables.nix
deleted file mode 100644
index ee403432..00000000
--- a/modules/wu/iptables.nix
+++ /dev/null
@@ -1,69 +0,0 @@
-{ config, pkgs, ... }:
-
-{
-  #
-  # iptables
-  #
-  networking.firewall.enable = false;
-  system.activationScripts.iptables =
-    let
-      log = false;
-      when = c: f: if c then f else "";
-    in
-      ''
-        ip4tables() { ${pkgs.iptables}/sbin/iptables "$@"; }
-        ip6tables() { ${pkgs.iptables}/sbin/ip6tables "$@"; }
-        ipXtables() { ip4tables "$@"; ip6tables "$@"; }
-
-        #
-        # nat
-        #
-
-        # reset tables
-        ipXtables -t nat -F
-        ipXtables -t nat -X
-
-        #
-        ipXtables -t nat -A PREROUTING -j REDIRECT ! -i retiolum -p tcp --dport ssh --to-ports 0
-        ipXtables -t nat -A PREROUTING -j REDIRECT -p tcp --dport 11423 --to-ports ssh
-
-        #
-        # filter
-        #
-
-        # reset tables
-        ipXtables -P INPUT DROP
-        ipXtables -P FORWARD DROP
-        ipXtables -F
-        ipXtables -X
-
-        # create custom chains
-        ipXtables -N Retiolum
-
-        # INPUT
-        ipXtables -A INPUT -j ACCEPT -m conntrack --ctstate RELATED,ESTABLISHED
-        ipXtables -A INPUT -j ACCEPT -i lo
-        ipXtables -A INPUT -j ACCEPT -p tcp --dport ssh -m conntrack --ctstate NEW
-        ipXtables -A INPUT -j ACCEPT -p tcp --dport http -m conntrack --ctstate NEW
-        ipXtables -A INPUT -j ACCEPT -p tcp --dport tinc -m conntrack --ctstate NEW
-        ipXtables -A INPUT -j ACCEPT -p tcp --dport smtp -m conntrack --ctstate NEW
-        ipXtables -A INPUT -j Retiolum -i retiolum
-        ${when log "ipXtables -A INPUT -j LOG --log-level info --log-prefix 'INPUT DROP '"}
-
-        # FORWARD
-        ${when log "ipXtables -A FORWARD -j LOG --log-level info --log-prefix 'FORWARD DROP '"}
-
-        # Retiolum
-        ip4tables -A Retiolum -j ACCEPT -p icmp --icmp-type echo-request
-        ip6tables -A Retiolum -j ACCEPT -p ipv6-icmp -m icmp6 --icmpv6-type echo-request
-
-
-        ${when log "ipXtables -A Retiolum -j LOG --log-level info --log-prefix 'REJECT '"}
-        ipXtables -A Retiolum -j REJECT -p tcp --reject-with tcp-reset
-        ip4tables -A Retiolum -j REJECT -p udp --reject-with icmp-port-unreachable
-        ip4tables -A Retiolum -j REJECT        --reject-with icmp-proto-unreachable
-        ip6tables -A Retiolum -j REJECT -p udp --reject-with icmp6-port-unreachable
-        ip6tables -A Retiolum -j REJECT
-
-      '';
-}