Configure ClamAV + C-ICAP server

To configure an ICAP server using an open-source solution, you can follow the guide provided at ICAP Server Setup Guide. Here's a detailed breakdown of the key concepts and steps involved in the process.

ICAP Server Overview

The Internet Content Adaptation Protocol (ICAP) is an HTTP extension that allows intermediaries to modify HTTP traffic. ICAP servers can perform functions such as content filtering, virus scanning, and compression.

Prerequisites

• A Linux-based server (e.g., Ubuntu, CentOS)
• Apache HTTP Server installed
• ICAP-enabled proxy (e.g., Squid)
• ICAP module for Apache (e.g., mod_icap)
• ICAP server software (e.g., ClamAV for antivirus scanning)

Step 1: Install Apache HTTP Server

Follow the instructions for your specific Linux distribution to install Apache HTTP Server.

Step 2: Install ICAP module for Apache

For this example, we'll use the mod_icap module. Install it using the following command:

sudo apt-get install libapache2-mod-icap

Step 3: Enable and configure the ICAP module

Enable the ICAP module by adding the following lines to your Apache configuration file (usually located at /etc/apache2/apache2.conf or /etc/httpd/conf/httpd.conf):

LoadModule icap_module modules/mod_icap.so
ICAPServer server.example.com 127.0.0.1 1344

Replace server.example.com with your server's domain name or IP address.

Step 4: Install ICAP server software

For this example, we'll use ClamAV as an antivirus scanner. Install it using the following commands:

sudo apt-get update
sudo apt-get install clamav clamav-daemon

Step 5: Configure ClamAV

Edit the ClamAV configuration file (usually located at /etc/clamav/clamd.conf) and add the following lines:

Port 1344
User clamav
Group clamav

Step 6: Configure ICAP server

Create a new file called icap.conf in the Apache configuration directory (usually located at /etc/apache2/conf-available or /etc/httpd/conf.d/) and add the following content:

<Location /icap/>
  ICAPServer server.example.com 127.0.0.1 1344
  ICAPSendHeader On
  ICAPSendBody On
  ICAPSendResponse On
  ICAPSendError On
  ICAPSendRequest On
  ICAPLogLevel 7
  ICAPLogFile /var/log/apache2/icap.log
</Location>

Step 7: Enable and configure Squid

Install Squid (an ICAP-enabled proxy) using the following command:

sudo apt-get install squid

Edit the Squid configuration file (usually located at /etc/squid/squid.conf) and add the following lines:

http_access allow localhost
http_port 3128 icp-port 3130
icp_port 3130
icp_children 5
icp_program /usr/bin/icap_send
icp_header_access From allow all

Step 8: Restart Apache and Squid

Restart both Apache and Squid to apply the changes:

sudo systemctl restart apache2
sudo systemctl restart squid

Summary

In this article, we've covered the steps to configure an ICAP server using an open-source solution. The guide provided focuses on setting up an antivirus scanner using ClamAV and Apache HTTP Server with Squid as the ICAP-enabled proxy.

References

• ICAP Server Setup Guide
• ClamAV Installation Guide
• Squid Installation Guide