Objective:
This paper mainly introduces the use of Squid and Squidguard configuration Proxy server in Linux, with the WWW Proxy service as an example to explain how to filter harmful sites and restrict users ' access to the Internet.
I. INTRODUCTION
Squid is the most popular proxy server software under Linux, it is powerful, support for Http,ftp,gopher,ssl and WAIS, and other protocols agent; Simple to set, the proxy server can be run with a slight change in the configuration file. And squid has the page caching function, it receives the user's download request, and automatically processes the downloaded data. That is, when a user wants to download a homepage, it sends a request to squid to download it for it, then squid connects to the requested Web site and requests the home page, and then passes the home page to the user while retaining a backup, when another user applies for the same page, Squid passes the saved backup to the user immediately, making the user feel very fast.
Squidguard is the Assistant software for squid, which completes the function of filtering, redirection and access control. It is a free software, features strong, easy to install, easy to configure, and processing speed. Features include: Restricting access to some users based on a Web server or list of URLs, blocking access to Web servers and URLs on the blacklist, blocking access to URLs that are matched by certain users to regular expressions, and enforcing domain access in URL paths that prohibit IP access; Redirect blocked URLs to a smart CGI information page, redirect unauthorized users to a registration page, have access rules based on date, week, day, and different rules for different user groups. However, you cannot filter, check text in documents, and JavaScript or VBScript scripting languages in HTML.
Two. Installation
1. Install Squid:
Download from www.squid-cache.org squid-2.4.stable2-src.tar.gz exists under local/usr/local/squid/src.
Before compiling squid, create a user and group dedicated to running squid, where a group and user named Squid are set up and the user directory is set to/usr/local/squid
#su Squid
$CD/USR/LOCAL/SQUID/SRC
$tar Xvzf squid-2.4.stable2-src.tar.gz
$ CD Squid-2.4.stable2
$./configure
$make
$make Install
(Installed by default to the/usr/local/squid directory)
2. Install Berkeley DB 2.x:
From http://www.sleepycat.com download db-2.7.7.tar.gz coexist in/usr/local/squidguard/src/directory
$su
#cd/usr/local/squidguard/src/
#tar Xvzf db-2.7.7.tar.gz
#cd db-2.7.7
#cd Build_unix
#.. /dist/configure
#make
#make Install
(Installed by default to the/usr/local/berkeleydb directory)
Note: Squidguard does not support Berkeley DB 3.x version
3. Install Squidguard
From http://ftp.ost.eltele.no/pub/www/proxy/squidGuard/squidGuard-1.1.4.tar.gz download packages coexist in local/usr/local/squidguard/src/
#cd/usr/local/squidguard/src/
#tar Xvzf squidguard-1.1.4.tar.gz
#cd squidGuard-1.1.4
#./configure--with-sg-config=/usr/local/squidguard/squidguard.conf
--with-sg-logdir=/usr/local/squidguard/logs
--with-sg-dbhome=/usr/local/squidguard/db
#make
#make Test//test OK for the next installation
#make Install