Merge pull request #4121 from wkennington/master.nat

nixos/nat: Don't flush tables, create subchains for autogenerated rules
This commit is contained in:
William A. Kennington III 2014-09-18 16:30:42 -07:00
commit 1ff027b304
4 changed files with 90 additions and 73 deletions

View file

@ -13,38 +13,49 @@ let
dest = if cfg.externalIP == null then "-j MASQUERADE" else "-j SNAT --to-source ${cfg.externalIP}";
flushNat = ''
iptables -w -t nat -F PREROUTING
iptables -w -t nat -F POSTROUTING
iptables -w -t nat -X
iptables -w -t nat -D PREROUTING -j nixos-nat-pre 2>/dev/null|| true
iptables -w -t nat -F nixos-nat-pre 2>/dev/null || true
iptables -w -t nat -X nixos-nat-pre 2>/dev/null || true
iptables -w -t nat -D POSTROUTING -j nixos-nat-post 2>/dev/null || true
iptables -w -t nat -F nixos-nat-post 2>/dev/null || true
iptables -w -t nat -X nixos-nat-post 2>/dev/null || true
'';
setupNat = ''
# Create subchain where we store rules
iptables -w -t nat -N nixos-nat-pre
iptables -w -t nat -N nixos-nat-post
# We can't match on incoming interface in POSTROUTING, so
# mark packets coming from the external interfaces.
${concatMapStrings (iface: ''
iptables -w -t nat -A PREROUTING \
iptables -w -t nat -A nixos-nat-pre \
-i '${iface}' -j MARK --set-mark 1
'') cfg.internalInterfaces}
# NAT the marked packets.
${optionalString (cfg.internalInterfaces != []) ''
iptables -w -t nat -A POSTROUTING -m mark --mark 1 \
iptables -w -t nat -A nixos-nat-post -m mark --mark 1 \
-o ${cfg.externalInterface} ${dest}
''}
# NAT packets coming from the internal IPs.
${concatMapStrings (range: ''
iptables -w -t nat -A POSTROUTING \
iptables -w -t nat -A nixos-nat-post \
-s '${range}' -o ${cfg.externalInterface} ${dest}
'') cfg.internalIPs}
# NAT from external ports to internal ports.
${concatMapStrings (fwd: ''
iptables -w -t nat -A PREROUTING \
iptables -w -t nat -A nixos-nat-pre \
-i ${cfg.externalInterface} -p tcp \
--dport ${builtins.toString fwd.sourcePort} \
-j DNAT --to-destination ${fwd.destination}
'') cfg.forwardPorts}
# Append our chains to the nat tables
iptables -w -t nat -A PREROUTING -j nixos-nat-pre
iptables -w -t nat -A POSTROUTING -j nixos-nat-post
'';
in
@ -157,7 +168,7 @@ in
extraStopCommands = flushNat;
};
systemd.services = mkIf (!config.networking.firewall.enable) { nat = {
systemd.services = mkIf (!config.networking.firewall.enable) { nat = {
description = "Network Address Translation";
wantedBy = [ "network.target" ];
after = [ "network-interfaces.target" "systemd-modules-load.service" ];

View file

@ -61,7 +61,8 @@ in rec {
(all nixos.tests.kde4)
(all nixos.tests.login)
(all nixos.tests.misc)
(all nixos.tests.nat)
(all nixos.tests.nat.firewall)
(all nixos.tests.nat.standalone)
(all nixos.tests.nfs3)
(all nixos.tests.openssh)
(all nixos.tests.printing)

View file

@ -244,7 +244,8 @@ in rec {
tests.munin = callTest tests/munin.nix {};
tests.mysql = callTest tests/mysql.nix {};
tests.mysqlReplication = callTest tests/mysql-replication.nix {};
tests.nat = callTest tests/nat.nix {};
tests.nat.firewall = callTest tests/nat.nix { withFirewall = true; };
tests.nat.standalone = callTest tests/nat.nix { withFirewall = false; };
tests.nfs3 = callTest tests/nfs.nix { version = 3; };
tests.nsd = callTest tests/nsd.nix {};
tests.openssh = callTest tests/openssh.nix {};

View file

@ -3,77 +3,81 @@
# client on the inside network, a server on the outside network, and a
# router connected to both that performs Network Address Translation
# for the client.
import ./make-test.nix ({ withFirewall, ... }:
let
unit = if withFirewall then "firewall" else "nat";
in
{
name = "nat${if withFirewall then "WithFirewall" else "Standalone"}";
import ./make-test.nix {
name = "nat";
nodes =
{ client =
{ config, pkgs, nodes, ... }:
{ virtualisation.vlans = [ 1 ];
networking.firewall.allowPing = true;
networking.defaultGateway =
(pkgs.lib.head nodes.router.config.networking.interfaces.eth2.ip4).address;
};
nodes =
{ client =
{ config, pkgs, nodes, ... }:
{ virtualisation.vlans = [ 1 ];
networking.firewall.allowPing = true;
networking.defaultGateway =
(pkgs.lib.head nodes.router.config.networking.interfaces.eth2.ip4).address;
};
router =
{ config, pkgs, ... }:
{ virtualisation.vlans = [ 2 1 ];
networking.firewall.enable = withFirewall;
networking.firewall.allowPing = true;
networking.nat.enable = true;
networking.nat.internalIPs = [ "192.168.1.0/24" ];
networking.nat.externalInterface = "eth1";
};
router =
{ config, pkgs, ... }:
{ virtualisation.vlans = [ 2 1 ];
networking.firewall.allowPing = true;
networking.nat.enable = true;
networking.nat.internalIPs = [ "192.168.1.0/24" ];
networking.nat.externalInterface = "eth1";
};
server =
{ config, pkgs, ... }:
{ virtualisation.vlans = [ 2 ];
networking.firewall.enable = false;
services.httpd.enable = true;
services.httpd.adminAddr = "foo@example.org";
services.vsftpd.enable = true;
services.vsftpd.anonymousUser = true;
};
};
server =
{ config, pkgs, ... }:
{ virtualisation.vlans = [ 2 ];
networking.firewall.enable = false;
services.httpd.enable = true;
services.httpd.adminAddr = "foo@example.org";
services.vsftpd.enable = true;
services.vsftpd.anonymousUser = true;
};
};
testScript =
{ nodes, ... }:
''
startAll;
testScript =
{ nodes, ... }:
''
startAll;
# The router should have access to the server.
$server->waitForUnit("network.target");
$server->waitForUnit("httpd");
$router->waitForUnit("network.target");
$router->succeed("curl --fail http://server/ >&2");
# The router should have access to the server.
$server->waitForUnit("network.target");
$server->waitForUnit("httpd");
$router->waitForUnit("network.target");
$router->succeed("curl --fail http://server/ >&2");
# The client should be also able to connect via the NAT router.
$router->waitForUnit("${unit}");
$client->waitForUnit("network.target");
$client->succeed("curl --fail http://server/ >&2");
$client->succeed("ping -c 1 server >&2");
# The client should be also able to connect via the NAT router.
$router->waitForUnit("nat");
$client->waitForUnit("network.target");
$client->succeed("curl --fail http://server/ >&2");
$client->succeed("ping -c 1 server >&2");
# Test whether passive FTP works.
$server->waitForUnit("vsftpd");
$server->succeed("echo Hello World > /home/ftp/foo.txt");
$client->succeed("curl -v ftp://server/foo.txt >&2");
# Test whether passive FTP works.
$server->waitForUnit("vsftpd");
$server->succeed("echo Hello World > /home/ftp/foo.txt");
$client->succeed("curl -v ftp://server/foo.txt >&2");
# Test whether active FTP works.
$client->succeed("curl -v -P - ftp://server/foo.txt >&2");
# Test whether active FTP works.
$client->succeed("curl -v -P - ftp://server/foo.txt >&2");
# Test ICMP.
$client->succeed("ping -c 1 router >&2");
$router->succeed("ping -c 1 client >&2");
# Test ICMP.
$client->succeed("ping -c 1 router >&2");
$router->succeed("ping -c 1 client >&2");
# If we turn off NAT, the client shouldn't be able to reach the server.
$router->succeed("iptables -t nat -D PREROUTING -j nixos-nat-pre");
$router->succeed("iptables -t nat -D POSTROUTING -j nixos-nat-post");
$client->fail("curl --fail --connect-timeout 5 http://server/ >&2");
$client->fail("ping -c 1 server >&2");
# If we turn off NAT, the client shouldn't be able to reach the server.
$router->stopJob("nat");
$client->fail("curl --fail --connect-timeout 5 http://server/ >&2");
$client->fail("ping -c 1 server >&2");
# And make sure that restarting the NAT job works.
$router->succeed("systemctl start nat");
$client->succeed("curl --fail http://server/ >&2");
$client->succeed("ping -c 1 server >&2");
'';
}
# And make sure that reloading the NAT job works.
$router->succeed("systemctl restart ${unit}");
$client->succeed("curl --fail http://server/ >&2");
$client->succeed("ping -c 1 server >&2");
'';
})