depot/ops/nixos/lib/bgp.nix

369 lines
14 KiB
Nix

# SPDX-FileCopyrightText: 2020 Luke Granger-Brown <depot@lukegb.com>
#
# SPDX-License-Identifier: Apache-2.0
{ lib, config, ... }:
let
generateSnippet = base: args: lib.concatStringsSep "\n" (lib.mapAttrsToList ( ixName: ix: generateSnippetForIX (args // { ixName = ixName; ix = ix; }) ) base );
generateSnippetForIX = { ixName, ix, ... }@args: ''
ipv4 table ${ixName}4;
ipv6 table ${ixName}6;
filter bgp_in_${ixName}4
prefix set allnet;
int set allas;
{
if ! (avoid_martians4()) then reject;
${if ix.remote.must_be_next_hop then "if (bgp_path.first != ${toString ix.remote.asn}) then reject;" else "# no next-hop requirement"}
${lib.concatMapStringsSep "\n" (asn: "if (bgp_path ~ [= * ${toString asn} * =]) then reject;") ix.remote.drop_asns}
bgp_local_pref = ${toString ix.remote.bgp_local_pref};
accept;
}
filter bgp_in_${ixName}6
prefix set allnet;
int set allas;
{
if ! (avoid_martians6()) then reject;
${if ix.remote.must_be_next_hop then "if (bgp_path.first != ${toString ix.remote.asn}) then reject;" else "# no next-hop requirement"}
${lib.concatMapStringsSep "\n" (asn: "if (bgp_path ~ [= * ${toString asn} * =]) then reject;") ix.remote.drop_asns}
bgp_local_pref = ${toString ix.remote.bgp_local_pref};
accept;
}
protocol pipe ${ixName}pipe_4 {
table ${ixName}4;
peer table master4;
import where ((ro, ${toString ix.local.asn}, ${toString ix.remote.export_community}) ~ bgp_ext_community);
export filter bgp_in_${ixName}4;
};
protocol pipe ${ixName}pipe_6 {
table ${ixName}6;
peer table master6;
import where ((ro, ${toString ix.local.asn}, ${toString ix.remote.export_community}) ~ bgp_ext_community);
export filter bgp_in_${ixName}6;
};
'' + lib.concatImapStringsSep "\n" ( i: v: generateSnippetForRouter (args // { routerNum = i; router = v; }) ) ix.remote.routers;
enabledSnippet = { enabled ? true, ... }: "disabled ${if enabled then "off" else "on"};";
passwordSnippet = { password ? null, ... }: if password == null then "# no password" else "password \"${password}\";";
multihopSnippet = { multihop ? null, ... }: if multihop == null then "# not multihop" else "multihop ${toString multihop};";
passiveSnippet = { passive, ... }: "passive ${if passive then "on" else "off"};";
prefixLimitSnippet = limit: if limit == null then "# no import limit" else "import limit ${toString limit} action restart;";
generateSnippetForRouter = { ixName, ix, routerNum, router, ... }: ''
protocol bgp ${ixName}${toString routerNum}_4 {
${enabledSnippet router}
${passwordSnippet router}
${multihopSnippet router}
${passiveSnippet ix.remote}
local ${ix.local.v4} as ${toString ix.local.asn};
neighbor ${router.v4} as ${toString ix.remote.asn};
graceful restart on;
long lived graceful restart on;
ipv4 {
table ${ixName}4;
import all;
export where ((ro, ${toString ix.local.asn}, 1000) ~ bgp_ext_community);
${prefixLimitSnippet ix.remote.prefix_limit.v4}
};
};
protocol bgp ${ixName}${toString routerNum}_6 {
${enabledSnippet router}
${passwordSnippet router}
${multihopSnippet router}
${passiveSnippet ix.remote}
local ${ix.local.v6} as ${toString ix.local.asn};
neighbor ${router.v6} as ${toString ix.remote.asn};
graceful restart on;
long lived graceful restart on;
ipv6 {
table ${ixName}6;
import all;
export where ((ro, ${toString ix.local.asn}, 1000) ~ bgp_ext_community);
${prefixLimitSnippet ix.remote.prefix_limit.v6}
};
};
'';
inherit (lib) mkOption mkAfter types;
in {
options.services.lukegbgp = {
enable = mkOption {
type = types.bool;
default = false;
};
config = mkOption { # lukegbgp.config
type = with types; submodule {
options = {
local = mkOption { # lukegbgp.config.local
type = submodule {
options = {
routerID = mkOption { # lukegbgp.config.local.routerID
type = str;
};
};
};
};
peering = mkOption { # lukegbgp.config.peering
type = attrsOf (submodule {
options = {
local = mkOption { # lukegbgp.config.peering.<foo>.local
type = submodule {
options = {
asn = mkOption { # lukegbgp.config.peering.<foo>.local.asn
type = int;
};
v4 = mkOption { # lukegbgp.config.peering.<foo>.local.v4
type = str;
};
v6 = mkOption { # lukegbgp.config.peering.<foo>.local.v6
type = str;
};
};
};
};
remote = mkOption { # lukegbgp.config.peering.<foo>.remote
type = submodule {
options = {
asn = mkOption { # lukegbgp.config.peering.<foo>.remote.asn
type = int;
};
passive = mkOption { # lukegbgp.config.peering.<foo>.remote.passive
type = bool;
default = false;
};
export_community = mkOption { # lukegbgp.config.peering.<foo>.remote.export_community
type = int;
};
prefix_limit.v4 = mkOption { # lukegbgp.config.peering.<foo>.remote.prefix_limit.v4
type = nullOr int;
default = null;
};
prefix_limit.v6 = mkOption { # lukegbgp.config.peering.<foo>.remote.prefix_limit.v6
type = nullOr int;
default = null;
};
must_be_next_hop = mkOption { # lukegbgp.config.peering.<foo>.remote.must_be_next_hop
type = bool;
default = true;
};
drop_asns = mkOption { # lukegbgp.config.peering.<foo>.remote.drop_asns
type = listOf int;
default = [];
};
bgp_local_pref = mkOption { # lukegbgp.config.peering.<foo>.remote.bgp_local_pref
type = int;
default = 100;
};
routers = mkOption { # lukegbgp.config.peering.<foo>.remote.routers
type = listOf (submodule {
options = {
enabled = mkOption { # lukegbgp.config.peering.<foo>.remote.routers.<n>.enabled
type = bool;
default = true;
};
v4 = mkOption { # lukegbgp.config.peering.<foo>.remote.routers.<n>.v4
type = str;
};
v6 = mkOption { # lukegbgp.config.peering.<foo>.remote.routers.<n>.v6
type = str;
};
multihop = mkOption { # lukegbgp.config.peering.<foo>.remote.routers.<n>.multihop
type = nullOr int;
default = null;
};
password = mkOption { # lukegbgp.config.peering.<foo>.remote.routers.<n>.password
type = nullOr str;
default = null;
};
};
});
};
};
};
};
};
});
};
export = mkOption { # lukegbgp.config.export
default = { v4 = []; v6 = ["2a09:a440::/48"]; };
type = submodule {
options = {
v4 = mkOption { # lukegbgp.config.export.v4
type = listOf str;
default = [];
};
v4Extra = mkOption { #lukegbgp.config.export.v4Extra
type = lines;
default = "";
};
v6 = mkOption { # lukegbgp.config.export.v6
type = listOf str;
default = ["2a09:a440::/48"];
};
v6Extra = mkOption { #lukegbgp.config.export.v6Extra
type = lines;
default = "";
};
};
};
};
bfd = mkOption { # lukegbgp.config.bfd
type = lines;
default = "";
};
};
};
};
};
config = {
services.bird2 = lib.mkIf config.services.lukegbgp.enable {
enable = true;
config = ''
router id ${config.services.lukegbgp.config.local.routerID};
function avoid_martians4()
prefix set martians;
{
martians = [
169.254.0.0/16+,
172.16.0.0/12+,
192.168.0.0/16+,
192.0.0.0/24+,
192.0.2.0/24+,
192.88.99.0/24+,
198.18.0.0/15+,
198.51.100.0/24+,
203.0.113.0/24+,
10.0.0.0/8+,
100.64.0.0/10+,
224.0.0.0/4+,
240.0.0.0/4+,
0.0.0.0/32-,
0.0.0.0/0{25,32},
0.0.0.0/0{0,7} ];
if net ~ martians then return false;
return true;
}
function avoid_martians6()
prefix set martians;
{
martians = [
::/128-,
::1/128-,
::ffff:0:0/96+,
::ffff:0:0:0/96+,
64:ff9b::/96+,
100::/64+,
::/0{64,128},
::/0{0,15},
2001:db8::/32+,
fc00::/7+,
fe80::/10+,
ff00::/8+ ];
if net ~ martians then return false;
return true;
}
${generateSnippet config.services.lukegbgp.config.peering {}}
protocol kernel {
persist;
ipv4 {
import none;
export all;
};
};
protocol kernel {
persist;
ipv6 {
import none;
export all;
};
};
protocol device {
};
protocol static export4 {
ipv4 {
import filter {
bgp_ext_community.add((ro, 205479, 1000));
bgp_ext_community.add((ro, 205479, 2000));
bgp_ext_community.add((ro, 205479, 2001));
bgp_ext_community.add((ro, 205479, 2002));
bgp_ext_community.add((ro, 205479, 2003));
bgp_ext_community.add((ro, 205479, 3000));
bgp_ext_community.add((ro, 205479, 4000));
bgp_ext_community.add((ro, 205479, 4001));
bgp_ext_community.add((ro, 205479, 4002));
bgp_ext_community.add((ro, 205479, 5000));
bgp_ext_community.add((ro, 205479, 5001));
bgp_ext_community.add((ro, 205479, 5002));
bgp_ext_community.add((ro, 205479, 5003));
bgp_ext_community.add((ro, 205479, 5004));
bgp_ext_community.add((ro, 205479, 5005));
bgp_ext_community.add((ro, 205479, 5006));
bgp_ext_community.add((ro, 205479, 5007));
bgp_ext_community.add((ro, 205479, 5008));
bgp_ext_community.add((ro, 205479, 5009)); # fastly from blade-tuvok
# do not export to clouvider; they do... strange things.
bgp_ext_community.add((rt, 0, 62240));
accept;
};
};
${lib.concatMapStrings (ip: "route ${ip} blackhole;") config.services.lukegbgp.config.export.v4}
${config.services.lukegbgp.config.export.v4Extra}
};
protocol static export6 {
ipv6 {
import filter {
bgp_ext_community.add((ro, 205479, 1000)); # export
bgp_ext_community.add((ro, 205479, 2000)); #
bgp_ext_community.add((ro, 205479, 2001)); #
bgp_ext_community.add((ro, 205479, 2002)); #
bgp_ext_community.add((ro, 205479, 2003)); #
bgp_ext_community.add((ro, 205479, 3000)); # clouvider from clouvider-lon01
bgp_ext_community.add((ro, 205479, 4000)); # frantech from frantech-nyc01/veloxserv from etheroute-lon01
bgp_ext_community.add((ro, 205479, 4001)); # veloxserv from blade-tuvok/blade-paris
bgp_ext_community.add((ro, 205479, 4002)); #
bgp_ext_community.add((ro, 205479, 5000)); # linx route collector from blade-tuvok
bgp_ext_community.add((ro, 205479, 5001)); # linx route server from blade-tuvok
bgp_ext_community.add((ro, 205479, 5002)); # facebook from blade-tuvok
bgp_ext_community.add((ro, 205479, 5003)); # openpeering from blade-tuvok
bgp_ext_community.add((ro, 205479, 5004)); # freetransitnet from blade-tuvok
bgp_ext_community.add((ro, 205479, 5005)); # he from blade-tuvok
bgp_ext_community.add((ro, 205479, 5006)); # clouvider from blade-tuvok
bgp_ext_community.add((ro, 205479, 5007)); # google from blade-tuvok
bgp_ext_community.add((ro, 205479, 5008)); # cloudflare from blade-tuvok
bgp_ext_community.add((ro, 205479, 5009)); # fastly from blade-tuvok
# do not export to clouvider; they do... strange things.
bgp_ext_community.add((rt, 0, 62240));
accept;
};
};
${lib.concatMapStrings (ip: "route ${ip} blackhole;") config.services.lukegbgp.config.export.v6}
${config.services.lukegbgp.config.export.v6Extra}
};
protocol bfd {
${config.services.lukegbgp.config.bfd}
};
'';
};
services.prometheus.exporters.bird.enable = config.services.bird2.enable;
networking.firewall.allowedTCPPorts = lib.mkIf config.services.lukegbgp.enable (lib.mkAfter [ 179 ]);
networking.firewall.checkReversePath = false;
boot.kernel.sysctl = {
"net.ipv6.conf.default.accept_ra" = 0;
"net.ipv6.conf.all.accept_ra" = 0;
"net.ipv6.conf.default.autoconf" = 0;
"net.ipv6.conf.all.autoconf" = 0;
};
};
}