帯域制限モジュール mod_qos

mod_qos

http://mod-qos.sourceforge.net/
QoS (Quality of Service) の制御を可能とするモジュール。
Slowloris 攻撃の対策に Lynis にサジェストされる。

インストール

yum install epel-release && yum update
yum install mod_qos

公式のサンプル

cat << "_EOF_" >> /etc/httpd/conf.modules.d/10-mod_qos.conf

QS_ErrorPage                  /error-docs/qs_error.html

# restricts max concurrent requests for any location which has no
# individual rule:
QS_LocRequestLimitDefault                              200

# limits access to *.gif files to 100 concurrent requests:
QS_LocRequestLimitMatch       "^.*\.gif$"              100

# limits concurrent requests to the locations /images and /app/a:
QS_LocRequestLimit            /images                  100
QS_LocRequestLimit            /app/a                   300
# limits download bandwidth to 5Mbit/sec:
QS_LocKBytesPerSecLimit       /app/a                   640

# two locations (/app/b and /app/c) representing a single application:
QS_LocRequestLimitMatch       "^(/app/b/|/app/c/).*$"  300


# allows the application to nominate VIP users by sending a
# "mod-qos-vip" HTTP response header:
QS_VipHeaderName              mod-qos-vip
QS_SessionKey                 na&5san-sB.F4_0a=%D200ahLK1

<Location /qos>
   SetHandler qos-viewer
</Location>
<Location /qos/console>
   SetHandler qos-console
</Location>
_EOF_

コマンド

/usr/bin 配下に以下のコマンドがインストールされる。

• qscheck
  • Monitor programm testing the TCP connectivity to servers.

• qsfilter2

  • access/audit ログから QS_Permit* ディレクティブとルールパターンを作成するルールジェネレーター

• qsgeo

  • Adds the country code for the client IP address within a log file.

• qsgrep

  • Searches a file for a pattern and prints the data in a new format.

• qshead

  • an utility reading from stdin and printing all lines to stdout until reaching the defined pattern.

• qslogger

  • Shell command interface to the syslog(3) system log module.

• qspng

  • Creates graphics (png images) from the output of qslog.

• qssign

  • A log data integrity check tool. It reads log data from stdin (pipe) and writes the signed data to stdout adding a sequence number and signatur to ever log line.
  • qssign.rb is a Logstash filter plugin which may be used to verify the signatures of log messages in real time.

• qstail

  • Shows the end of a log file beginning at a defined pattern.