nixos/fail2ban: add custom options

This commit is contained in:
Izorkin 2019-12-02 20:19:16 +03:00
parent a55be8d794
commit f1d7dfe29f

View file

@ -62,6 +62,108 @@ in
description = "The firewall package used by fail2ban service.";
};
banaction = mkOption {
default = "iptables-multiport";
type = types.str;
example = "nftables-multiport";
description = ''
Default banning action (e.g. iptables, iptables-new, iptables-multiport,
shorewall, etc) It is used to define action_* variables. Can be overridden
globally or per section within jail.local file
'';
};
banaction-allports = mkOption {
default = "iptables-allport";
type = types.str;
example = "nftables-allport";
description = ''
Default banning action (e.g. iptables, iptables-new, iptables-multiport,
shorewall, etc) It is used to define action_* variables. Can be overridden
globally or per section within jail.local file
'';
};
bantime-increment.enable = mkOption {
default = false;
type = types.bool;
description = ''
Allows to use database for searching of previously banned ip's to increase
a default ban time using special formula, default it is banTime * 1, 2, 4, 8, 16, 32...
'';
};
bantime-increment.rndtime = mkOption {
default = "4m";
type = types.str;
example = "8m";
description = ''
"bantime-increment.rndtime" is the max number of seconds using for mixing with random time
to prevent "clever" botnets calculate exact time IP can be unbanned again
'';
};
bantime-increment.maxtime = mkOption {
default = "10h";
type = types.str;
example = "48h";
description = ''
"bantime-increment.maxtime" is the max number of seconds using the ban time can reach (don't grows further)
'';
};
bantime-increment.factor = mkOption {
default = "1";
type = types.str;
example = "4";
description = ''
"bantime-increment.factor" is a coefficient to calculate exponent growing of the formula or common multiplier,
default value of factor is 1 and with default value of formula, the ban time grows by 1, 2, 4, 8, 16 ...
'';
};
bantime-increment.formula = mkOption {
default = "ban.Time * (1<<(ban.Count if ban.Count<20 else 20)) * banFactor";
type = types.str;
example = "ban.Time * math.exp(float(ban.Count+1)*banFactor)/math.exp(1*banFactor)";
description = ''
"bantime-increment.formula" used by default to calculate next value of ban time, default value bellow,
the same ban time growing will be reached by multipliers 1, 2, 4, 8, 16, 32...
'';
};
bantime-increment.multipliers = mkOption {
default = "1 2 4 8 16 32 64";
type = types.str;
example = "2 4 16 128";
description = ''
"bantime-increment.multipliers" used to calculate next value of ban time instead of formula, coresponding
previously ban count and given "bantime.factor" (for multipliers default is 1);
following example grows ban time by 1, 2, 4, 8, 16 ... and if last ban count greater as multipliers count,
always used last multiplier (64 in example), for factor '1' and original ban time 600 - 10.6 hours
'';
};
bantime-increment.overalljails = mkOption {
default = false;
type = types.bool;
example = true;
description = ''
"bantime-increment.overalljails" (if true) specifies the search of IP in the database will be executed
cross over all jails, if false (dafault), only current jail of the ban IP will be searched
'';
};
ignoreIP = mkOption {
default = [ ];
type = types.listOf types.str;
example = [ "192.168.0.0/16" "2001:DB8::42" ];
description = ''
"ignoreIP" can be a list of IP addresses, CIDR masks or DNS hosts. Fail2ban will not ban a host which
matches an address in this list. Several addresses can be defined using space (and/or comma) separator.
'';
};
daemonConfig = mkOption {
default = ''
[Definition]
@ -160,10 +262,22 @@ in
# Add some reasonable default jails. The special "DEFAULT" jail
# sets default values for all other jails.
services.fail2ban.jails.DEFAULT = ''
${optionalString cfg.bantime-increment.enable ''
# Bantime incremental
bantime.increment = ${if cfg.bantime-increment.enable then "true" else "false"}
bantime.maxtime = ${cfg.bantime-increment.maxtime}
bantime.factor = ${cfg.bantime-increment.factor}
bantime.formula = ${cfg.bantime-increment.formula}
bantime.multipliers = ${cfg.bantime-increment.multipliers}
bantime.overalljails = ${if cfg.bantime-increment.overalljails then "true" else "false"}
''}
# Miscellaneous options
ignoreip = 127.0.0.1/8 ${optionalString config.networking.enableIPv6 "::1"}
ignoreip = 127.0.0.1/8 ${optionalString config.networking.enableIPv6 "::1"} ${concatStringsSep " " cfg.ignoreIP}
maxretry = 3
backend = systemd
# Actions
banaction = ${cfg.banaction}
banaction_allports = ${cfg.banaction-allports}
'';
# Block SSH if there are too many failing connection attempts.
services.fail2ban.jails.sshd = mkDefault ''