Merge pull request #834 from robho/yate_nftables_banbrutes

yate: Update yate script to use an nftables set
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micmac1 2023-11-05 09:31:45 +01:00 committed by GitHub
commit add9143fca
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2 changed files with 61 additions and 25 deletions

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@ -10,7 +10,7 @@ include $(TOPDIR)/rules.mk
PKG_NAME:=yate
PKG_VERSION:=6.4.0-1
PKG_RELEASE:=2
PKG_RELEASE:=3
PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz
PKG_SOURCE_URL:=http://yate.null.ro/tarballs/yate6/

View file

@ -1,21 +1,43 @@
#!/usr/bin/perl
# This yate module will monitor failed authentications and send the source
# IP addresses of users who fail to authenticate to the iptables extension
# "recent" for filtering.
# This yate script will monitor authentication requests and update an
# nftables set with IP addresses of users who consistently fail to
# authenticate. The nftables set can then be used in OpenWrt's
# firewall configuration to block these IP addresses.
#
# You have to have the iptables extension "recent" installed and you need to
# create and reference a "recent" list in your firewall configuration.
# For most people it's probably enough to add this custom firewall rule
# to /etc/firewall.user:
# The nftables set has to exist before launching yate.
#
# iptables -A input_rule -m recent --name yate_auth_failures --rcheck --seconds 3600 --hitcount 5 -j DROP
# Here's an example configuration that creates an nftables set, where
# entries expire after 12 hours, and configures the OpenWrt firewall
# to drop packets where the source IP address is in the set. Put this
# in /etc/nftables.d/99-yate.nft:
#
# This line will drop all incoming traffic from users who have failed to
# authenticate 5 consecutive times within the last hour.
# set yate_denylist {
# type ipv4_addr
# timeout 12h
# }
#
# To enable this script in yate, add this script to the [scripts] section
# in /etc/yate/extmodule.conf.
# chain yate_filter {
# type filter hook input priority -1; policy accept;
# ip saddr @yate_denylist counter drop comment "Drop packets from bad SIP clients"
# }
#
#
# To enable this script in yate, add it to the [scripts] section in
# /etc/yate/extmodule.conf.
#
# You can tweak how tolerant this script should be by modifying the
# constants below.
# A user's IP address will be added to the nftables set if there are
# more than MAX_AUTH_FAILURES consecutive authentication failures in
# MAX_AUTH_FAILURES_TIME_PERIOD seconds.
my $MAX_AUTH_FAILURES = 5;
my $MAX_AUTH_FAILURES_TIME_PERIOD = 3600; # seconds
# The name of the nftables table and set where IP addresses are added.
my $NFTABLES_TABLE = 'inet fw4';
my $NFTABLES_SET = 'yate_denylist';
use strict;
@ -23,28 +45,42 @@ use warnings;
use lib '/usr/share/yate/scripts';
use Yate;
my $RECENT_LIST_NAME = '/proc/net/xt_recent/yate_auth_failures';
my %ip_auth_failures = ();
sub OnAuthenticationRequest($) {
my $yate = shift;
# Forget any expired failed authentications
foreach my $ip (keys(%ip_auth_failures)) {
my $failures = \@{$ip_auth_failures{$ip}};
while (@$failures &&
time() - @$failures[0] > $MAX_AUTH_FAILURES_TIME_PERIOD) {
shift(@$failures);
}
if (!@$failures) {
delete $ip_auth_failures{$ip};
}
}
my $remote_ip = $yate->param('ip_host');
my $remote_device = $yate->param('device') || '<unknown>';
if ($yate->header('processed') eq 'true') {
# Successful authentication, forget previous failures
`echo -$remote_ip > $RECENT_LIST_NAME`;
$yate->output("banbrutes: Successful authentication from $remote_ip");
delete $ip_auth_failures{$remote_ip};
return;
}
`echo +$remote_ip > $RECENT_LIST_NAME`;
$yate->output("banbrutes: Failed authentication from $remote_ip");
push(@{$ip_auth_failures{$remote_ip}}, time());
if (scalar(@{$ip_auth_failures{$remote_ip}}) > $MAX_AUTH_FAILURES) {
$yate->output("banbrutes: Adding $remote_ip to nftables set $NFTABLES_SET (remote device: $remote_device)");
`nft add element $NFTABLES_TABLE $NFTABLES_SET { $remote_ip }`;
delete $ip_auth_failures{$remote_ip};
}
}
my $yate = new Yate();
if (! -f $RECENT_LIST_NAME) {
$yate->output("iptables recent list $RECENT_LIST_NAME does not exist");
exit 1;
}
$yate->install_watcher('user.auth', \&OnAuthenticationRequest);
$yate->install_watcher("user.auth", \&OnAuthenticationRequest);
$yate->listen();