Danguardian and Squid Proxy

1
Danguardian and Squid Proxy

• Installation and Configuration

2
Outline

• Whats the Problem?
• Options - Ubuntu
• Getting Started Download Source File
• Tar and Gzip
• Squid
• Dansguardian
• Potential Problems and Suggestions

3
Motivation

• Become Familiar With Ubuntu Web-Filtering
• Filter Inappropriate Content
• Network Security
• User Protection
• Lost Productivity
• Legal Issues
• Adverse Publicity

4
Dansguardian and Squid Proxy

• Ubuntu" is an ancient African word, meaning
  "humanity to others". Ubuntu also means "I am
  what I am because of who we all are".
• Internet Is a Mixed Blessing
• Moral Obligations
• Ethical Obligations
• Contractual Obligations
• Productivity
• Solution 1 Dont Engage in Inappropriate
  Activity
• Solution 2- Web Filtering

5
Solution 2 - Ubuntu Options

• Tradeoff Between Flexibility and Control
• Ubuntu Includes Over 16,000 Pieces of SW
• Ubuntu Core Installation Files Fit on a CD
• Ubuntu SW Includes Word Processors, Spreadsheets,
  Web Server SW, Email SW, etc.
• Dansguardian (Content Filter version 2.9.9.3)
• Squid (Caching Proxy version 3.0)

6
Download/Extract Dansguardian

• Use the Wget command several options
• tar -xvzf dansguardian-2.9.9.3.tar.gz
• -xvzf option
• -x option to extract
• -v option for verbosity
• -z option to unzip
• -f to use the tarfile argument as the file name

7
Squid

• Caching Proxy Server
• Supports HTTP, HTTPS, FTP and more
• Reduces Bandwidth
• Improves Response Time
• Extensive Access Controls
• Great Server Accelerator
• Runs on UNIX and Windows

8
Squid Configuration

• Configure squid.conf
• Use a Text Editor, i.e., vi, pico, etc.
• Comment the recommended configuration
• After acl CONNECT method CONNECT , Enter Your
  Network Information in the Next Two Lines
• Example in Next Slide
• Comment ( ) http_access deny !safe_ports
• ( approximately line 1760 )

9
squid.conf

• acl localnet src 128.198.61.0/255.255.255.0
• acl all src 128.198.61.0/255.255.255.0
• acl manager proto cache_object
• acl localhost src 127.0.0.1/255.255.255.255
• acl SSL_ports port 443 563
• http_access allow localnet
• http_access allow localhost
• http_access allow CONNECT SSL_ports
• http_access deny all

10
Dansguardian Configuration

• cd /.configure
• make
• make install
• make clean
• Enter crontab -e and
• Enter
• 59 23 sat etc/dansguardian/logrotation

11
Dansguardian Configuration, contd.

• Path to config file is . . .
• /etc/dansguardian/dansguardian.conf
• Set Proxy IP128.198.61.253
• ( actual IP of server running
  dansguardian )
• Set Access Denied Address to DG Server IP
• accessdeniedaddresshttp//128.198.61.253/cg
  i-bin/dansguardian.pl
• Save and Restart

12
Potential Problems/Improvements

• Forgetting to Setup Proxy Server in Browser
• Default port is 8080
• make file or devel-tools missing
• Flexibility and Control Balancing Act
• Many available Blacklists are outdated
• Users Find Ways to Get Around Content Filters
• Use Updated Blacklists Supported by Commercial
  Products such as SmoothWall, ( Content Firewall )

13
References

• http//dansguardian.org
• http//www.sequentialart.com/article/php?id103
• http//ubuntuforums.org/showthread/php?t277178
• http//www.ubuntu.com
• http//sourceforge.net/docman/index.php?group_id1
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