CrOS/modules/services/fail2ban/default.nix
2025-08-22 22:52:35 -04:00

45 lines
1.8 KiB
Nix

{
inputs,
config,
pkgs,
...
}: {
environment.etc = {
# Define an action that will trigger a Ntfy push notification upon the issue of every new ban
"fail2ban/action.d/ntfy.local".text = pkgs.lib.mkDefault (pkgs.lib.mkAfter ''
[Definition]
norestored = true # Needed to avoid receiving a new notification after every restart
actionban = curl -H "Title: <ip> has been banned" -d "<name> jail has banned <ip> from accessing ${config.hostSpec.hostName} after <failures> attempts of attacking the system." https://notify.wanderingcrow.net/Fail2banNotifications
'');
# Defines a filter that detects URL probing by reading the Nginx access log
"fail2ban/filter.d/nginx-ddos-protect.local".text = pkgs.lib.mkDefault (pkgs.lib.mkAfter ''
[Definition]
failregex = ^<HOST> - - \[.*\] "GET .* HTTP/.*" \d{3} \d+ "-" "ApacheBench/.+"
limiting requests, excess:.* by zone.*client: <HOST>
^.*\[error\]\s+\d+#\d+:\s+\*\d+\s+connect\(\) to unix:.*failed.*while connecting to upstream,\s+client:\s+<HOST>,\s+server:.*
^.*\[error\]\s+\d+#\d+:\s+\*\d+\s+upstream prematurely closed connection while reading response header from upstream,\s+client:\s+<HOST>,.*$
ignoreregex =
'');
};
services.fail2ban = {
enable = true;
extraPackages = [
pkgs.curl
];
ignoreIP = [
inputs.nix-secrets.network.primary.publicIP
];
jails = {
nginx-ddos-protect.settings = {
enabled = true;
filter = "nginx-ddos-protect";
logpath = "/var/log/nginx/*.log";
action = '' %(action_)s[blocktype=DROP]
ntfy'';
backend = "auto"; # Do not forget to specify this if your jail uses a log file
maxretry = 1;
findtime = 3600;
};
};
};
}