dotfiles/nixos/systems/omen/firewall.nix
2023-10-07 22:45:51 +02:00

178 lines
7.9 KiB
Nix

{ secret, inputs', pkgs, ... }:
{
networking.notnft.rules =
let
notnft = (inputs'.notnft.lib.${pkgs.stdenv.system});
logRule = with notnft.dsl; with payload; prefix:
[ (log { prefix = "${prefix} dropped: "; flags = (f: [ f.all ]); } ) ];
traceChain = with notnft.dsl; with payload;
add chain
[ (is.eq th.dport 53) (mangle meta.nftrace 1) ]
[ (is.eq th.dport 53) (mangle meta.nftrace 1) ]
[ (is.eq th.dport 22) (mangle meta.nftrace 1) ]
[ (is.eq th.sport 22) (mangle meta.nftrace 1) ]
[ (is.eq meta.oifname "mvm0") (mangle meta.nftrace 1) ]
[ (is.eq meta.iifname "mvm0") (mangle meta.nftrace 1) ];
in
# pkgs.writeText "nftables.json" (builtins.toJSON (with notnft.dsl; with payload; ruleset
with notnft.dsl; with payload; ruleset {
filter = add table { family = f: f.inet; } {
trace = traceChain;
### lo
input-lo = add chain
[ (is.ne ip.saddr (set [ "127.0.0.1" "127.0.0.53" ])) drop ]
[ (is.ne ip.daddr (set [ "127.0.0.1" "127.0.0.53" ])) drop ]
[ accept ];
output-lo = add chain
[ accept ];
###
### mvm
input-mvm = add chain
[ (is.eq ip.protocol (f: f.icmp)) accept ];
output-mvm = add chain
[ (is.eq ip.protocol (f: f.icmp)) (is.eq ip.saddr "10.80.1.1") (is.eq ip.daddr "10.80.1.2") accept ]
[ (is.eq ip.protocol (f: f.icmp)) (is.eq ip.saddr "10.80.1.2") (is.eq ip.daddr "10.80.1.1") accept ]
[ (is.eq ip.protocol (f: with f; set [ tcp ])) (is.eq th.dport 22) (is.eq ip.saddr "10.80.1.1") (is.eq ip.daddr "10.80.1.2") accept ]
[ (is.eq ip.protocol (f: with f; set [ tcp ])) (is.eq th.dport 80) (is.eq ip.saddr "10.80.1.1") (is.eq ip.daddr "10.80.1.2") accept ];
###
### wlan0
input-wlan0 = add chain
[ drop ];
output-wlan0 = add chain
[ (is.ne ip.daddr (secret.network.ips.blowhole.ip or "")) (is.eq ip.protocol (f: with f; set [ tcp udp ])) (is.eq th.dport 53) drop ]
[ accept ];
###
### wlan0
input-eth0 = add chain
[ drop ];
output-eth0 = add chain
[ (is.ne ip.daddr (secret.network.ips.blowhole.ip or "")) (is.eq ip.protocol (f: with f; set [ tcp udp ])) (is.eq th.dport 53) drop ]
[ accept ];
###
### wg0
input-wg0 = add chain
# accept syncthing sharing
[ (is.eq ip.protocol (f: f.udp)) (is.eq th.sport "22000") (is.eq th.dport "22000") accept ]
[ (is.eq ip.protocol (f: f.tcp)) (is.eq th.dport "22000") accept ]
[ (is.eq ip.protocol (f: f.icmp)) accept ];
output-wg0 = add chain
# TCP, UDP 53 to blowhole
[ (is.eq ip.protocol (f: with f; set [ udp tcp ])) (is.eq th.dport 53) (is.eq ip.saddr (secret.network.ips.omen.vpn or "")) (is.eq ip.daddr (secret.network.ips.blowhole.ip or "")) accept ]
# TCP 22, 80, 4646, 8200, 8500, 2049 to blowhole
[ (is.eq ip.protocol (f: with f; set [ tcp ])) (is.eq th.dport (set [ 22 80 4646 8200 8500 2049 ])) (is.eq ip.saddr (secret.network.ips.omen.vpn or "")) (is.eq ip.daddr (secret.network.ips.blowhole.ip or "")) accept ]
# TCP 22 toothpick
[ (is.eq ip.protocol (f: with f; set [ tcp ])) (is.eq th.dport (set [ 22 ])) (is.eq ip.saddr (secret.network.ips.omen.vpn or "")) (is.eq ip.daddr (secret.network.ips.toothpick or "")) accept ]
# TCP 22 altra
[ (is.eq ip.protocol (f: with f; set [ tcp ])) (is.eq th.dport (set [ 22 ])) (is.eq ip.saddr (secret.network.ips.omen.vpn or "")) (is.eq ip.daddr (secret.network.ips.altra.ip or "")) accept ]
# ICMP to blowhole, toothpick
[ (is.eq ip.protocol (f: f.icmp)) (is.eq ip.saddr (secret.network.ips.omen.vpn or "")) (is.eq ip.daddr (set [ (secret.network.ips.toothpick or "") (secret.network.ips.altra.ip or "") (secret.network.ips.blowhole.ip or "") ])) accept ]
# accept syncthing sharing
[ (is.eq ip.protocol (f: f.udp)) (is.eq th.sport "22000") (is.eq th.dport "22000") accept ]
[ (is.eq ip.protocol (f: f.tcp)) (is.eq th.dport "22000") accept ]
;
###
input = add chain { type = f: f.filter; hook = f: f.input; prio = -300; policy = f: f.drop; }
# accept related, established and drop invalid
[ (vmap ct.state { established = accept; related = accept; invalid = drop; }) ]
# # accept icmp between the same IP
# [ (is.eq ip.protocol (f: f.icmp)) (is.eq ip.daddr ip.saddr) accept ]
[ (jump "trace") ]
[ (is.eq meta.iifname "wlan0") (jump "input-wlan0") ]
[ (is.eq meta.iifname "eth0") (jump "input-eth0") ]
[ (is.eq meta.iifname "mvm0") (jump "input-mvm") ]
[ (is.eq meta.iifname "lo") (jump "input-lo") ]
[ (is.eq meta.iifname "wg0") (jump "input-wg0") ]
[ (is.eq ip.protocol (f: f.icmp)) accept ]
(logRule "Input");
output = add chain { type = f: f.filter; hook = f: f.output; prio = -300; policy = f: f.drop; }
[ (jump "trace") ]
[ (is.eq meta.oifname "wlan0") (jump "output-wlan0") ]
[ (is.eq meta.oifname "eth0") (jump "output-eth0") ]
[ (is.eq meta.oifname "lo") (jump "output-lo") ]
[ (is.eq meta.oifname "mvm0") (jump "output-mvm") ]
[ (is.eq meta.oifname "wg0") (jump "output-wg0") ]
(logRule "Output");
forward = add chain { type = f: f.filter; hook = f: f.forward; prio = -300; policy = f: f.drop; }
[ (jump "trace") ]
# accept masquaraded packets incoming from wg0
[ (is.eq meta.iifname "wg0") (vmap ct.state { established = accept; related = accept; }) ]
# accept TCP, UDP 53 from 10.80.1.2 to blowhole
[ (is.eq meta.iifname "mvm0") (is.eq meta.oifname "wg0") (is.eq ip.protocol (f: with f; set [ tcp udp ])) (is.eq th.dport 53) (is.eq ip.saddr "10.80.1.2") (is.eq ip.daddr (secret.network.ips.blowhole.ip or "")) accept ]
(logRule "Forward");
prerouting = add chain { type = f: f.nat; hook = f: f.prerouting; prio = -199; policy = f: f.accept; }
;
postrouting = add chain { type = f: f.nat; hook = f: f.postrouting; prio = -199; policy = f: f.accept; }
# masquarade from 10.80.1.2 heading to wg0
[ (is.eq meta.iifname "mvm0") (is.eq meta.oifname "wg0") (is.eq ip.saddr (set [ "10.80.1.2" ])) masquerade ];
};
bridge-t = add table { family = f: f.bridge; } {
trace = traceChain;
input-body = add chain;
input = add chain { type = f: f.filter; hook = f: f.input; prio = -300; policy = f: f.drop; }
[ (jump "trace") ]
[ (vmap ct.state { established = accept; related = accept; invalid = drop; }) ]
[ (is.eq meta.protocol (f: f.arp)) accept ]
[ (jump "input-body") ]
(logRule "Bridge input");
output-body = add chain;
output = add chain { type = f: f.filter; hook = f: f.output; prio = -300; policy = f: f.drop; }
[ (jump "trace") ]
[ (is.eq ether.type (f: f.arp)) accept ]
[ (jump "output-body") ]
(logRule "Bridge output");
forward-body = add chain;
forward = add chain { type = f: f.filter; hook = f: f.forward; prio = -300; policy = f: f.drop; }
[ (jump "trace") ]
[ (jump "forward-body") ]
(logRule "Bridge forward");
prerouting = add chain { type = f: f.filter; hook = f: f.prerouting; prio = -300; policy = f: f.accept; }
;
postrouting = add chain { type = f: f.filter; hook = f: f.postrouting; prio = -300; policy = f: f.accept; }
;
};
};
}