nixos/services/fail2ban.nix

69 lines
1.8 KiB
Nix

{ config, lib, pkgs, ... }:
# mostly taken from https://github.com/davidak/nixos-config/blob/master/services/fail2ban.nix
{
services.fail2ban = {
enable = true;
jails = {
DEFAULT = ''
bantime = 3600
logpath = /var/log/auth.log
'';
ssh = ''
enabled = true
filter = sshd
maxretry = 4
action = iptables[name=SSH, port=ssh, protocol=tcp]
'';
sshd-ddos = ''
enabled = true
filter = sshd-ddos
maxretry = 2
action = iptables[name=ssh, port=ssh, protocol=tcp]
'';
postfix = ''
enabled = true
filter = postfix
maxretry = 3
action = iptables[name=postfix, port=smtp, protocol=tcp]
'';
postfix-sasl = ''
enabled = true
filter = postfix-sasl
maxretry = 3
action = iptables[name=postfix, port=smtp, protocol=tcp]
'';
postfix-ddos = ''
enabled = true
filter = postfix-ddos
maxretry = 3
action = iptables[name=postfix, port=submission, protocol=tcp]
bantime = 7200
'';
nginx-req-limit = ''
enabled = true
filter = nginx-req-limit
maxretry = 10
action = iptables-multiport[name=ReqLimit, port="http,https", protocol=tcp]
findtime = 600
bantime = 7200
''
};
};
environment.etc."fail2ban/filter.d/postfix-ddos.conf".text = ''
[Definition]
failregex = lost connection after EHLO from \S+\[<HOST>\]
'';
environment.etc."fail2ban/filter.d/nginx-req-limit.conf".text = ''
[Definition]
failregex = limiting requests, excess:.* by zone.*client: <HOST>
'';
# Limit stack size to reduce memory usage
systemd.services.fail2ban.serviceConfig.LimitSTACK = 256 * 1024;
}