Squid Development Projects

Welcome to devel.squid-cache.org (aka squid.sourceforge.net).

The purpose of this site is to boost and open up Squid development for features not yet ready to be merged into the main Squid source tree. Anyone interested in developing some feature in Squid are welcome to host their development here for sharing with other Squid developers.

If you are interested in developing a feature for Squid, please write an description of what you are interested in doing and send this to squid-dev@squid-cache.org, and you will receive instructions on how to proceed.

Please note that everything found here unless otherwise announced is development branches with no guarantee of functionality or performance. Almost all the branches is very unstable as they in most cases are not yet finished and also have received very little testing.

If your are looking for a STABLE Squid version, or want to test the bleeding edge version of Squid then please look at the main Squid site instead. The development version found there has most finished projects found here in an integrated and somewhat tested form suitable for testing.

If you want to take active part in the development of a Squid feature while it is being actively developed or have been told by the developers than one of these branches is suitable for you then this site is for you and you may continue.

Table of contents

• Squid project page in SourceForge (login)
• How to become a Squid developer
• CVS repository information
• CVS changesets browser
• Rules for this site and CVS repository
• Squid projects hosted here
  • Microsoft Windows NT/2000 port
  • Code Optimization
  • ICAP Client Support (Squid-3)
  • ICAP Client Support (Squid-2)
  • Streaming ICAP Client Support
  • Experiment with the use of tries in squid string collections
  • Follow X-Forwarded-For headers
  • Optimize request forwarding for accelerator setups
  • Full etag and vary support
  • HTML Prefetching
  • IPv6 support for squid
  • Connection pinning
  • IPC refactoring
  • Using an external helper to perform Logfile IO
  • runtime gzip/deflate content-encoding
  • RFC 2616 (HTTP/1.1) support
  • IP based NTLM authentication cache
  • Squid 3.x Source Documentation Project
  • Modulize External Binaries.
  • New URL matching ACL (Squid-2)
  • New URL matching ACL (Squid-3)
  • Clean up and template the error pages
  • Rework the storeClientCopy() API to be reduce data copying
  • Embedded Content Adaptation (eCAP)
  • Native support for asynchronous calls
  • Mysql database logging and configuration reading feature
• Stale projects not being actively developed
  • Duplicate Storage Avoidance
  • Duplicate Transfer Detection
  • Squid Net I/O Performance Project
  • RTT based peer selection
  • Store Check
  • Store Partial Responses
  • NTLM smbpasswd helper
  • Stephen R. van den Berg's Squid-2.2 work
  • External logging capability
  • Push
  • sfs - another squid filesystem
  • Generic Modules
  • Content Processing
  • Event I/O model
  • Compact StoreEntry
  • Content Transfer Encoding
  • Content Transfer Encoding Modules
  • RAW ReiserFS support
  • Signal driven network I/O
  • Hot swap cache capability
• Completed projects
  • Support for large objects in Squid-3
  • Comm loops cleanup in Squid-2.6
  • Removal of Deferred reads for IO
  • WCCP V2 support
  • WCCP Version 2.0 Support
  • COSS Storage System
  • ETag support
  • Epoll Support
  • Negotiate authentication scheme
  • Support for fuzzy external acl lookups
  • Cerberian content filter support
  • Enhanced modular store I/O interface
  • Henrik Nordström's Squid work
  • Customizable log format
  • SSL gatewaying
  • External extensible ACL interface
  • Satellite link enhancements
  • Easier to use cbdata
  • Chunked MemPools
  • Reverse proxy enhancements
  • Autoconf 2.5 support
  • Selective access logging
  • ESI support for accelerators
  • Overlapping helper requests
  • ToS and/or outgoing IP selection
  • UNIX Domain IPC sockets
  • Refcounted allocator
  • Config pre-processing
  • deny_info with URL's
  • CARP peer selection cleanup
  • Digest (RFC 2617) authentication
  • Microsoft NTLM proxy authentication
  • Authentication rewrite
  • comm-select modules & optimizations
  • Authenticator protocol extensions
  • Adapt squid to use automake
  • ACL Work
  • generic cache_dir option parsing
  • Vary header support
  • Correct proxy_auth forwarding
  • /etc/hosts handling
  • Splay-tree-based User ACL verification
  • Asyncio/aufs optimization for Squid-2.4
  • Cross-site scripting issues
  • CPU high-res profiling
  • Large File support
  • Windows port using CYGWIN GNU toolchain
  • Service Enhancements to Windows CYGWIN port
  • Unification of IO.
• CVS commit log
• Draft HTTP/1.1 requirements list for squid

Links to other sites of interest to developers

• Squid's official home
• Squid Developers Corner
• squid-dev@squid-cache.org archives
• Squid programmers guide
• How to Write Secure Code
• Scour Transfer Protocol / 1.0
• WREC IEFT working group
  • Known HTTP Proxy/Caching Problems Draft
  • Web Cache Coordination Protocol v1.0 (WCCP) Draft
  • Web Cache Coordination Protocol v2.0 (WCCPv2) Draft
• Cache Array Routing Protocol (CARP)
• TUX
  • Ask Ingo article
  • SpecWeb Results article
• A scalable and explicit event delivery mechanism for UNIX (proposal for event based UNIX API)
• The C10K problem by Dan Kegel
• Joe Coopers Squid page
• Linux LFS
• X/Open LFS and more

Other known Squid works and patches not (yet) hosted here

• Zero Penalty Hit patch for SQUID (ZPH) by Marin Stavrev.
• Increase FD_SETSIZE on linux without editing system include files by Miquel van Smoorenburg (included in Squid-2.5 and later)
• Another patch to increase the amount of filedescriptors on Linux by Grahame Bowland
• Encrypted IP-Based authentication Idea by Steffen Dettmer
• Accelerator load balancing by Richard
• MySQL acl integration by Matthew Naylor
• SquidNG, a Squid using a custom reiserfs as storage.
• Group LDAP authentication by Tobias Crawley
• Extended Common Log file format by Jonathan Roy.
• Another Extended Common Log file format by Alex Kerkhove.
• And another Extendend Common Log file format by Michael A Nachbaur.
• Content filtering by Olaf Titz
• CacheExpress, NT Port of Squid-2.3, with some additions.
• PushCache Cuttlefish, A modified Squid implementing push caching.
• Central Squid Server, CSS, central cache state collection
• Stephen R. van den Berg (AKA BuGless)
• Disable animated gifs by Tim Newsome
• Latency hybrid removal policy (Squid-1.1.6 based)
• Some Squid patches by Pedro Ribeiro
• IPv6 patch to Squid 2.6.STABLE6 by Husni

Other Squid related works

• High Performance Web Caching With Squid article by Joe Cooper
• Squid Manual by Oscar Pearson
• Squid Guard
• Linux Journal Squid articles by David Guerrero
• squidproxyapps by Thomas Adam

Other proxy servers or similar programs

• NTLM Authorization Proxy Server by Dmitry Rozmanov is a proxy software that allows you to authenticate via an MS Proxy Server using the proprietary NTLM protocol. APS has the ability to behave as a standalone proxy server and authenticate HTTP clients at Web servers using the NTLM protocol.
• TNT (Tcp Net Tee) by Francesco 'kinkie' Chemolli is a port-forwarder with inspection capabilities and a few HTTP-related helping facilities. Requires the Pike programming language interpreter.
• frox, a transparent ftp proxy . has some support for caching through an external cache (eg. squid), or for maintaining a cache locally.
• PET, a cooperative WWW proxy cache supporting ICP and Cache Digests
• tcpproxy, a generic TCP/IP Proxy with traffic logging capabilities
• smtp.proxy, a proxy for SMTP
• pop3.proxy, a proxy for POP3
• rsh.proxy, a proxy for RSH
• ftp.proxy, a proxy for FTP
• FWTK, The FireWall ToolKit (FWTK) is a set of proxies which you can use to build your own firewall. (note: somewhat restrictive license)
• jftpgw, an FTP proxy/gateway
• FreshMeat "Old Appindex :: Daemons :: Proxy"