Junkbuster User Manual By: Junkbuster Developers Abstract The user manual gives the users information on how to install and configure Internet Junkbuster. Internet Junkbuster is an application that provides privacy and security to users of the World Wide Web. You can find the latest version of the user manual at [1]http://ijbswa.sourceforge.net/doc/user-manual/. Feel free to send a note to the developers at ijbswa-developers@lists.sourceforge.net . ____________________________________________________ Table of Contents [2]Introduction [3]Installation [4]Junkbuster Configuration [5]Quickstart to Using Junkbuster [6]Contact the Developers [7]Copyright and History [8]See also [9]Appendix Introduction Internet Junkbuster is a web proxy with advanced filtering capabilities for protecting privacy, filtering web page content, managing cookies, controlling access, and removing ads, banners, pop-ups and other obnoxious Internet Junk. Junkbuster has a very flexible configuration and can be customized to suit individual needs and tastes. Internet Junkbuster has application for both stand-alone systems and multi-user networks. This documentation is included with the current development version of Internet Junkbuster and is incomplete at this point. The most up to date reference for the time being is still the comments in the source files and in the individual configuration files. Development of version 3.0 is currently underway, and includes many significant changes and enhancements over earlier verions. The target release date for stable v3.0 is December 2001. Since this is a development version, some features are in the process of being implemented. This documentation may be slightly out of sync as a result. And there are bugs, though hopefully not many! _________________________________________________________________ New Features In addition to Junkbuster's traditional features of ad and banner blocking and cookie management, this is a list of new features currently under development: * Modularized configuration that will allow for system wide settings, and individual user settings. * A browser based GUI configuration utility (not finished). * Blocking of annoying pop-up browser windows (previously available as a patch). * Partial support for HTTP/1.1. * Support for Perl Compatible Regular Expressions in the configuration files, and generally a more sophisticated configuration syntax over previous versions. * Web page content filtering. * Multi-threaded. _________________________________________________________________ Installation Junkbuster is available as raw source code, or pre-compiled binaries. See the [10]Junkbuster Home Page for current release info. Junkbuster is also available via [11]CVS. This is the recommended approach at this time. But please be aware that CVS is constantly changing, and it may break in mysterious ways. _________________________________________________________________ Source For gzipped tar archives, unpack the source: tar zxvf ijb_source_2.9* cd ijb_source_2.9* For retrieving the current CVS sources, you'll need the CVS package installed first. To download CVS source: cvs -d:pserver:anonymous@cvs.ijbswa.sourceforge.net:/cvsroot/ijbswa login cvs -z3 -d:pserver:anonymous@cvs.ijbswa.sourceforge.net:/cvsroot/ijbswa co cu rrent cd current This will create a directory named current/, which will contain the source tree. Then, in either case, to build from source: ./configure make su make install For Redhat and SuSE Linux RPM packages, see below. _________________________________________________________________ Red Hat To build Redhat RPM packages, install source as above. Then: ./configure make redhat-dist This will create both binary and src RPMs in the usual places. Example: /usr/src/redhat/RPMS/i686/junkbuster-2.9.8-1.i686.rpm /usr/src/redhat/SRPMS/junkbuster-2.9.9-1.src.rpm To install, of course: rpm -Uvv /usr/src/redhat/RPMS/i686/junkbuster-2.9.9-1.i686.rpm This will place the Junkbuster configuration files in /etc/junkbuster/, and log files in /var/log/junkbuster/. _________________________________________________________________ SuSE To build SuSE RPM packages, install source as above. Then: ./configure make suse-dist This will create both binary and src RPMs in the usual places. Example: /usr/src/suse/RPMS/i686/junkbuster-2.9.9-1.i686.rpm /usr/src/suse/SRPMS/junkbuster-2.9.9-1.src.rpm To install, of course: rpm -Uvv /usr/src/suse/RPMS/i686/junkbuster-2.9.9-1.i686.rpm This will place the Junkbuster configuration files in /etc/junkbuster/, and log files in /var/log/junkbuster/. _________________________________________________________________ OS/2 The OS/2 version of Junkbuster requires the EMX runtime library to be installed. The EMX runtime library is available on the hobbes OS/2 archive, among many other locations: [12]http://hobbes.nmsu.edu/cgi-bin/h-search?sh=1&button=Search&key=emx rt.zip&stype=all&sort=type&dir=%2Fpub%2Fos2%2Fdev%2Femx%2Fv0.9d Junkbuster is packaged in a WarpIN self- installing archive. The self-installing program will be named depending on the release version, something like: ijbos123.exe. In order to install it, simply run this executable or double-click on its icon and follow the WarpIN installation panels. A shadow of the Junkbuster executable will be placed in your startup folder so it will start automatically whenever OS/2 starts. The directory you choose to install Junkbuster into will contain all of the configuration files. If you would like to build binary images on OS/2 yourself, you will need a working EMX/GCC environment, plus several Unix-like tools. The Hobbes OS/2 archive is a good place to start when building such an environment. A set of Unix-like tools named gnupack is located here: [13]http://hobbes.nmsu.edu/cgi-bin/h-search?sh=1&key=gnupack&stype=all &sort=type&dir=%2Fpub%2Fos2%2Fapps Once you have the source code unpacked as above, you can build the binaries from the current/ directory: autoconf sh configure make _________________________________________________________________ Windows Click-click. (I need help on this. Not a clue here. Also for configuration section below. HB.) _________________________________________________________________ Other Some quick notes on other Operating Systems. For FreeBSD (and other *BSDs?), the build will need gmake instead of the included make. gmake is available from [14]http://www.gnu.org. The rest should be the same as above for Linux/Unix. _________________________________________________________________ Junkbuster Configuration For Unix, *BSD and Linux, all configuraton files are located in /etc/junkbuster/ by default. For MS Windows and OS/2, these are all in the same directory as the Junkbuster executable. The name and number of configuration files has changed from previous versions, and is subject to change as development progresses. The installed defaults provide a reasonable starting point. For the time being, there are only three default configuration files (this will change in time): * The main configuration file is named config on Linux, Unix, BSD, and OS/2, and junkbustr.txt on Windows. On Amiga, it is AmiTCP:db/junkbuster/config. * The actionsfile file is used to define various actions relating to images, banners, pop-ups, banners and cookies. * The re_filterfile file can be used to rewrite the raw page content, including text as well as embedded HTML and JavaScript. actionsfile and re_filterfile can use Perl style regular expressions for maximum flexibility. All files use the "#" character to denote a comment. Such lines are not processed by Junkbuster. After making any changes, restart Junkbuster in order for the changes to take effect. _________________________________________________________________ The Main Configuration File Again, the main configuration file is named config on Linux/Unix/BSD and OS/2, and junkbustr.txt on Windows. Configuration lines consist of an initial keyword followed by a list of values, all separated by whitespace (any number of spaces or tabs). For example: blockfile blocklist.ini Indicates that the blockfile is named "blocklist.ini". The "#" indicates a comment. Any part of a line following a "#" is ignored, except if the "#" is preceded by a "\". Thus, by placing a "#" at the start of an existing configuration line, you can make it a comment and it will be treated as if it weren't there. This is called "commenting out" an option and can be useful to turn off features: If you comment out the "logfile" line, junkbuster will not log to a file at all. Watch for the "default:" section in each explanation to see what happens if the option is left unset (or commented out). Long lines can be continued on the next line by using a "\" as the very last character. There are various aspects of Junkbuster behavior that can be adjusted. _________________________________________________________________ Defining Other Configuration Files Junkbuster can use a number of other files to tell it what ads to block, what cookies to accept, etc. This section of the configuration file tells Junkbuster where to find all those other files. On Windows, Junkbuster looks for these files in the same directory as the executable. On Unix and OS/2, Junkbuster looks for these files in the current working directory. In either case, an absolute path name can be used to avoid problems. When development goes modular and multiuser, the blocker, filter, and per-user config will be stored in subdirectories of "confdir". For now, only confdir/templates is used for storing HTML templates for CGI results. The location of the configuration files: confdir /etc/junkbuster # No trailing /, please. The directory where all logging (i.e. logfile and jarfile) takes place. No trailing "/", please: logdir /var/log/junkbuster Note that all file specifications below are relative to the above two directories! The "actionsfile" contains patterns to specify the actions to apply to requests for each site. Default: Cookies to and from all destinations are filtered. Popups are disabled for all sites. All sites are filtered if re_filterfile specified. No sites are blocked. An empty image is displayed for filtered ads and other images (formerly "tinygif"). The syntax of this file is explained in detail [15]below. actionsfile actionsfile The "re_filterfile" file contains content modification rules. These rules permit powerful changes on the content of Web pages, e.g., you could disable your favourite JavaScript annoyances, rewrite the actual content, or just have some fun replacing "Microsoft" with "MicroSuck" wherever it appears on a Web page. Default: No content modification, or whatever the developers are playing with :-/ re_filterfile re_filterfile The logfile is where all logging and error messages are written. The logfile can be useful for tracking down a problem with Junkbuster (e.g., it's not blocking an ad you think it should block) but in most cases you probably will never look at it. Your logfile will grow indefinitely, and you will probably want to periodically remove it. On Unix systems, you can do this with a cron job (see "man cron"). For Redhat, a logrotate script has been included. On SuSE Linux systems, you can place a line like "/var/log/junkbuster.* +1024k 644 nobody.nogroup" in /etc/logfiles, with the effect that cron.daily will automatically archive, gzip, and empty the log, when it exceeds 1M size. Default: Log to the a file named logfile. Comment out to disable logging. logfile logfile The "jarfile" defines where Junkbuster stores the cookies it intercepts. Note that if you use a "jarfile", it may grow quite large. Default: Don't store intercepted cookies. #jarfile jarfile If you specify a "trustfile", Junkbuster will only allow access to sites that are named in the trustfile. You can also mark sites as trusted referrers, with the effect that access to untrusted sites will be granted, if a link from a trusted referrer was used. The link target will then be added to the "trustfile". This is a very restrictive feature that typical users most propably want to leave disabled. Default: Disabled, don't use the trust mechanism. #trustfile trust If you use the trust mechanism, it is a good idea to write up some online documentation about your blocking policy and to specify the URL(s) here. They will appear on the page that your users receive when they try to access untrusted content. Use multiple times for multiple URLs. Default: Don't display links on the "untrusted" info page. trust-info-url http://www.your-site.com/why_we_block.html trust-info-url http://www.your-site.com/what_we_allow.html _________________________________________________________________ Other Configuration Options This part of the configuration file contains options that control how Junkbuster operates. "Admin-address" should be set to the email address of the proxy administrator. It is used in many of the proxy-generated pages. Default: fill@me.in.please. #admin-address fill@me.in.please "Proxy-info-url" can be set to a URL that contains more info about this Junkbuster installation, it's configuration and policies. It is used in many of the proxy-generated pages and its use is highly recommended in multi-user installations, since your users will want to know why certain content is blocked or modified. Default: Don't show a link to online documentation. proxy-info-url http://www.your-site.com/proxy.html "Listen-address" specifies the address and port where Junkbuster will listen for connections from your Web browser. The default is to listen on the localhost port 8000, and this is suitable for most users. (In your web browser, under proxy configuration, list the proxy server as "localhost" and the port as "8000"). If you already have another service running on port 8000, or if you want to serve requests from other machines (e.g. on your local network) as well, you will need to override the default. The syntax is "listen-address []:". If you leave out the IP adress, junkbuster will bind to all interfaces (addresses) on your machine and may become reachable from the internet. In that case, consider using access control lists (acl's) (see "aclfile" above). For example, suppose you are running Junkbuster on a machine which has the address 192.168.0.1 on your local private network (192.168.0.0) and has another outside connection with a different address. You want it to serve requests from inside only: listen-address 192.168.0.1:8000 If you want it to listen on all addresses (including the outside connection): listen-address :8000 If you do this, consider using ACLs (see "aclfile" above). Note: you will need to point your browser(s) to the address and port that you have configured here. Default: localhost:8000 (127.0.0.1:8000). The debug option sets the level of debugging information to log in the logfile (and to the console in the Windows version). A debug level of 1 is informative because it will show you each request as it happens. Higher levels of debug are probably only of interest to developers. debug 1 # GPC = show each GET/POST/CONNECT request debug 2 # CONN = show each connection status debug 4 # IO = show I/O status debug 8 # HDR = show header parsing debug 16 # LOG = log all data into the logfile debug 32 # FRC = debug force feature debug 64 # REF = debug regular expression filter debug 128 # = debug fast redirects debug 256 # = debug GIF deanimation debug 512 # CLF = Common Log Format debug 1024 # = debug kill popups debug 4096 # INFO = Startup banner and warnings. debug 8192 # ERROR = Non-fatal errors It is highly recommended that you enable ERROR reporting (debug 8192), at least until the next stable release. The reporting of FATAL errors (i.e. ones which crash JunkBuster) is always on and cannot be disabled. If you want to use CLF (Common Log Format), you should set "debug 512" ONLY, do not enable anything else. Multiple "debug" directives, are OK - they're logical-OR'd together. debug 15 # same as setting the first 4 listed above Default: debug 1 # URLs debug 4096 # Info debug 8192 # Errors - *we highly recommended enabling this* Junkbuster normally uses "multi-threading", a software technique that permits it to handle many different requests simultaneously. In some cases you may wish to disable this -- particularly if you're trying to debug a problem. The "single-threaded" option forces Junkbuster to handle requests sequentially. Default: Multi-threaded mode. #single-threaded "toggle" allows you to temporarily disable all Junkbuster's filtering. Just set "toggle 0". The Windows version of Junkbuster puts an icon in the system tray, which allows you to change this option without having to edit this file. If you right-click on that icon (or select the "Options" menu), one choice is "Enable". Clicking on enable toggles Junkbuster on and off. This is useful if you want to temporarily disable Junkbuster, e.g., to access a site that requires cookies which you normally have blocked. "toggle 1" means Junkbuster runs normally, "toggle 0" means that Junkbuster becomes a non-anonymizing non-blocking proxy. Default: 1. toggle 1 _________________________________________________________________ Access Control List (ACL) Access controls are included at the request of some ISPs and systems administrators, and are not usually needed by individual users. Please note the warnings in the FAQ that this proxy is not intended to be a substitute for a firewall or to encourage anyone to defer addressing basic security weaknesses. If no access settings are specified, the proxy talks to anyone that connects. If any access settings file are specified, then the proxy talks only to IP addresses permitted somewhere in this file and not denied later in this file. Summary -- if using an ACL: Client must have permission to receive service. LAST match in ACL wins. Default behavior is to deny service. The syntax for an entry in the Access Control List is: ACTION SRC_ADDR[/SRC_MASKLEN] [ DST_ADDR[/DST_MASKLEN] ] Where the individual fields are: ACTION = "permit-access" or "deny-access" SRC_ADDR = client hostname or dotted IP address SRC_MASKLEN = number of bits in the subnet mask for the source DST_ADDR = server or forwarder hostname or dotted IP address DST_MASKLEN = number of bits in the subnet mask for the target The field separator (FS) is whitespace (space or tab). IMPORTANT NOTE: If the junkbuster is using a forwarder (see below) or a gateway for a particular destination URL, the DST_ADDR that is examined is the address of the forwarder or the gateway and NOT the address of the ultimate target. This is necessary because it may be impossible for the local Junkbuster to determine the address of the ultimate target (that's often what gateways are used for). Here are a few examples to show how the ACL features work: "localhost" is OK -- no DST_ADDR implies that ALL destination addresses are OK: permit-access localhost A silly example to illustrate permitting any host on the class-C subnet with Junkbuster to go anywhere: permit-access www.junkbusters.com/24 Except deny one particular IP address from using it at all: deny-access ident.junkbusters.com You can also specify an explicit network address and subnet mask. Explicit addresses do not have to be resolved to be used. permit-access 207.153.200.0/24 A subnet mask of 0 matches anything, so the next line permits everyone. permit-access 0.0.0.0/0 Note, you cannot say: permit-access .org to allow all *.org domains. Every IP address listed must resolve fully. An ISP may want to provide a Junkbuster that is accessible by "the world" and yet restrict use of some of their private content to hosts on its internal network (i.e. its own subscribers). Say, for instance the ISP owns the Class-B IP address block 123.124.0.0 (a 16 bit netmask). This is how they could do it: permit-access 0.0.0.0/0 0.0.0.0/0 # other clients can go anywhere # with the following exceptions : deny-access 0.0.0.0/0 123.124.0.0/16 # block all external request s for # sites on the ISP's network permit 0.0.0.0/0 www.my_isp.com # except for the ISP's main # web site permit 123.124.0.0/16 0.0.0.0/0 # the ISP's clients can go # anywhere Note that if some hostnames are listed with multiple IP addresses, the primary value returned by DNS (via gethostbyname()) is used. Default: Anyone can access the proxy. _________________________________________________________________ Forwarding This feature allows chaining of HTTP requests via multiple proxies. It can be used to better protect privacy and confidentiality when accessing specific domains by routing requests to those domains to a special purpose filtering proxy such as lpwa.com. It can also be used in an environment with multiple networks to route requests via multiple gateways allowing transparent access to multiple networks without having to modify browser configurations. Also specified here are SOCKS proxies. Junkbuster SOCKS 4 and SOCKS 4A. The difference is that SOCKS 4A will resolve the target hostname using DNS on the SOCKS server, not our local DNS client. The syntax of each line is: forward target_domain[:port] http_proxy_host[:port] forward-socks4 target_domain[:port] socks_proxy_host[:port] http_proxy_host[:port] forward-socks4a target_domain[:port] socks_proxy_host[:port] http_proxy_host[:port] If http_proxy_host is ".", then requests are not forwarded to a HTTP proxy but are made directly to the web servers. Lines are checked in sequence, and the last match wins. There is an implicit line equivalent to the following, which specifies that anything not finding a match on the list is to go out without forwarding or gateway protocol, like so: forward .* . # implicit In the following common configuration, everything goes to Lucent's LPWA, except SSL on port 443 (which it doesn't handle): forward .* lpwa.com:8000 forward :443 . See the FAQ for instructions on how to automate the login procedure for LPWA. Some users have reported difficulties related to LPWA's use of "." as the last element of the domain, and have said that this can be fixed with this: forward lpwa. lpwa.com:8000 (NOTE: the syntax for specifiying target_domain has changed since the previous paragraph was written -- it will not work now. More information is welcome.) In this fictitious example, everything goes via an ISP's caching proxy, except requests to that ISP: forward .* caching.myisp.net:8000 forward myisp.net . For the @home network, we're told the forwarding configuration is this: forward .* proxy:8080 Also, we're told they insist on getting cookies and JavaScript, so you need to add home.com to the cookie file. We consider JavaScript a security risk. Java need not be enabled. In this example direct connections are made to all "internal" domains, but everything else goes through Lucent's LPWA by way of the company's SOCKS gateway to the Internet. forward_socks4 .* lpwa.com:8000 firewall.my_company.com:1080 forward my_company.com . This is how you could set up a site that always uses SOCKS but no forwarders: forward_socks4a .* . firewall.my_company.com:1080 An advanced example for network administrators: If you have links to multiple ISPs that provide various special content to their subscribers, you can configure forwarding to pass requests to the specific host that's connected to that ISP so that everybody can see all of the content on all of the ISPs. This is a bit tricky, but here's an example: host-a has a PPP connection to isp-a.com. And host-b has a PPP connection to isp-b.com. host-a can run a Junkbuster proxy with forwarding like this: forward .* . forward isp-b.com host-b:8000 host-b can run a Junkbuster proxy with forwarding like this: forward .* . forward isp-a.com host-a:8000 Now, anyone on the Internet (including users on host-a and host-b) can set their browser's proxy to either host-a or host-b and be able to browse the content on isp-a or isp-b. Here's another practical example, for University of Kent at Canterbury students with a network connection in their room, who need to use the University's Squid web cache. forward *. ssbcache.ukc.ac.uk:3128 # Use the proxy, except for: forward .ukc.ac.uk . # Anything on the same domain as us forward * . # Host with no domain specified forward 129.12.*.* . # A dotted IP on our /16 network. forward 127.*.*.* . # Loopback address forward localhost.localdomain . # Loopback address forward www.ukc.mirror.ac.uk . # Specific host If you intend to chain Junkbuster and squid locally, then chain as browser -> squid -> junkbuster is the recommended way. Your squid configuration could then look like this: # Define junkbuster as parent cache cache_peer 127.0.0.1 parent 8000 0 no-query # Define ACL for protocol FTP acl FTP proto FTP # Do not forward ACL FTP to junkbuster always_direct allow FTP # Do not forward ACL CONNECT (https) to junkbuster always_direct allow CONNECT # Forward the rest to junkbuster never_direct allow all _________________________________________________________________ Windows GUI Options Junkbuster has a number of options specific to the Windows GUI interface: If "activity-animation" is set to 1, the Junkbuster icon will animate when "Junkbuster" is active. To turn off, set to 0. activity-animation 1 If "log-messages" is set to 1, Junkbuster will log messages to the console window: log-messages 1 If "log-buffer-size" is set to 1, the size of the log buffer, i.e. the amount of memory used for the log messages displayed in the console window, will be limited to "log-max-lines" (see below). Warning: Setting this to 0 will result in the buffer to grow infinitely and eat up all your memory! log-buffer-size 1 log-max-lines is the maximum number of lines held in the log buffer. See above. log-max-lines 200 If "log-highlight-messages" is set to 1, Junkbuster will highlight portions of the log messages with a bold-faced font: log-highlight-messages 1 The font used in the console window: log-font-name Comic Sans MS Font size used in the console window: log-font-size 8 "show-on-task-bar" controls whether or not Junkbuster will appear as a button on the Task bar when minimized: show-on-task-bar 0 If "close-button-minimizes" is set to 1, the Windows close button will minimize Junkbuster instead of closing the program (close with the exit option on the File menu). close-button-minimizes 1 The "hide-console" option is specific to the MS-Win console version of JunkBuster. If this option is used, Junkbuster will disconnect from and hide the command console. #hide-console _________________________________________________________________ The Actions File The "actionsfile" is used to define what actions Junkbuster takes, and thus determines how images, cookies and various other aspects of HTTP content and transactions are handled. Images can be anything you want, including ads, banners, or just some obnoxious image that you would rather not see. Cookies can be accepted or rejected. The default file is in fact named actionsfile. To determine which actions apply to a request, the URL of the request is compared to all patterns in this file. Every time it matches, the list of applicable actions for the URL is incrementally updated. You can trace this process by visiting [16]http://i.j.b/show-url-info. There are four types of lines in this file: comments (begin with a "#" character), actions, aliases and patterns, all of which are explained below. _________________________________________________________________ URL Domain and Path Syntax Generally, a pattern has the form /, where both the and part are optional. If you only specify a domain part, the "/" can be left out: www.example.com - is a domain only pattern and will match any request to "www.example.com". www.example.com/ - means exactly the same. www.example.com/index.html - matches only the single document "/index.html" on "www.example.com". /index.html - matches the document "/index.html", regardless of the domain. index.html - matches nothing, since it would be interpreted as a domain name and there is no top-level domain called ".html". The matching of the domain part offers some flexible options: if the domain starts or ends with a dot, it becomes unanchored at that end. For example: .example.com - matches any domain that ENDS in ".example.com". www. - matches any domain that STARTS with "www". Additionally, there are wildcards that you can use in the domain names themselves. They work pretty similar to shell wildcards: "*" stands for zero or more arbitrary characters, "?" stands for any single character. And you can define charachter classes in square brackets and they can be freely mixed: ad*.example.com - matches "adserver.example.com", "ads.example.com", etc but not "sfads.example.com". *ad*.example.com - matches all of the above, and then some. .?pix.com - matches "www.ipix.com", "pictures.epix.com", "a.b.c.d.e.upix.com", etc. www[1-9a-ez].example.com - matches "www1.example.com", "www4.example.com", "wwwd.example.com", "wwwz.example.com", etc., but not "wwww.example.com". If Junkbuster was compiled with "pcre" support (default), Perl compatible regular expressions can be used. See the pcre/docs/ direcory or "man perlre" (also available on [17]http://www.perldoc.com/perl5.6/pod/perlre.html) for details. A brief discussion of regular expressions is in the [18]Appendix. For instance: /.*/advert[0-9]+\.jpe?g - would match a URL from any domain, with any path that includes "advert" followed immediately by one or more digits, then a "." and ending in either "jpeg" or "jpg". So we match "example.com/ads/advert2.jpg", and "www.example.com/ads/banners/advert39.jpeg", but not "www.example.com/ads/banners/advert39.gif" (no gifs in the example pattern). Please note that matching in the path is case INSENSITIVE by default, but you can switch to case sensitive at any point in the pattern by using the "(?-i)" switch: www.example.com/(?-i)PaTtErN.* - will match only documents whose path starts with "PaTtErN" in exactly this capitalization. _________________________________________________________________ Actions Actions are enabled if preceded with a "+", and disabled if preceded with a "-". Actions are invoked by enclosing the action name in curly braces (e.g. {+some_action}), followed by a list of URLs to which the action applies. There are three classes of actions: * Boolean (e.g. "+/-block"): {+name} # enable this action {-name} # disable this action * Parameterized (e.g. "+/-hide-user-agent"): {+name{param}} # enable action and set parameter to "param" {-name} # disable action * Multi-value (e.g. "{+/-add-header{Name: value}}", "{+/-wafer{name=value}}"): {+name{param}} # enable action and add parameter "param" {-name{param}} # remove the parameter "param" {-name} # disable this action totally If nothing is specified in this file, no "actions" are taken. So in this case JunkBuster would just be a normal, non-blocking, non-anonymizing proxy. You must specifically enable the privacy and blocking features you need (although the provided default actionsfile file will give a good starting point). Later defined actions always over-ride earlier ones. For multi-valued actions, the actions are applied in the order they are specified. The list of valid Junkbuster "actions" are: * Add the specified HTTP header, which is not checked for validity. You may specify this many times to specify many different headers: +add-header{Name: value} * Block this URL totally. +block * De-animate all animated GIF images, i.e. reduce them to their last frame. This will also shrink the images considerably (in bytes, not pixels!). If the option "first" is given, the first frame of the animation is used as the replacement. If "last" is given, the last frame of the animation is used instead, which propably makes more sense for most banner animations, but also has the risk of not showing the entire last frame (if it is only a delta to an earlier frame). +deanimate-gifs{last} +deanimate-gifs{first} * "+downgrade" will downgrade HTTP/1.1 client requests to HTTP/1.0 and downgrade the responses as well. Use this action for servers that use HTTP/1.1 protocol features that Junkbuster doesn't handle well yet. HTTP/1.1 is only partially implemented. Default is not to downgrade requests. +downgrade * Many sites, like yahoo.com, don't just link to other sites. Instead, they will link to some script on their own server, giving the destination as a parameter, which will then redirect you to the final target. URLs resulting from this scheme typically look like: http://some.place/some_script?http://some.where-else. Sometimes, there are even multiple consecutive redirects encoded in the URL. These redirections via scripts make your web browing more traceable, since the server from which you follow such a link can see where you go to. Apart from that, valuable bandwidth and time is wasted, while your browser ask the server for one redirect after the other. Plus, it feeds the advertisers. The "+fast-redirects" option enables interception of these requests by Junkbuster, who will cut off all but the last valid URL in the request and send a local redirect back to your browser without contacting the remote site. +fast-redirects * Filter the website through the re_filterfile: +filter{filename} * Block any existing X-Forwarded-for header, and do not add a new one: +hide-forwarded * If the browser sends a "From:" header containing your e-mail address, this either completely removes the header ("block"), or changes it to the specified e-mail address. +hide-from{block} +hide-from{spam@sittingduck.xqq} * Don't send the "Referer:" (sic) header to the web site. You can block it, forge a URL to the same server as the request (which is preferred because some sites will not send images otherwise) or set it to a constant string of your choice. +hide-referer{block} +hide-referer{forge} +hide-referer{http://nowhere.com} * Alternative spelling of "+hide-referer". It has the same parameters, and can be freely mixed with, "+hide-referer". ("referrer" is the correct English spelling, however the HTTP specification has a bug - it requires it to be spelled "referer".) +hide-referrer{...} * Change the "User-Agent:" header so web servers can't tell your browser type. Warning! This breaks many web sites. Specify the user-agent value you want. Example, pretend to be using Netscape on Linux: +hide-user-agent{Mozilla (X11; I; Linux 2.0.32 i586)} * Treat this URL as an image. This only matters if it's also "+block"ed, in which case a "blocked" image can be sent rather than a HTML page. See "+image-blocker{}" below for the control over what is actually sent. +image * Decides what to do with URLs that end up tagged with "{+block +image}". There are 4 options. "-image-blocker" will send a HTML "blocked" page, usually resulting in a "broken image" icon. "+image-blocker{logo}" will send a "JunkBuster" image. "+image-blocker{blank}" will send a 1x1 transparent GIF image. And finally, "+image-blocker{http://xyz.com}" will send a HTTP temporary redirect to the specified image. This has the advantage of the icon being being cached by the browser, which will speed up the display. +image-blocker{logo} +image-blocker{blank} +image-blocker{http://i.j.b/send-banner} * By default (i.e. in the absence of a "+limit-connect" action), Junkbuster will only allow CONNECT requests to port 443, which is the standard port for https as a precaution. The CONNECT methods exists in HTTP to allow access to secure websites (https:// URLs) through proxies. It works very simply: the proxy connects to the server on the specified port, and then short-circuits its connections to the client and to the remote proxy. This can be a big security hole, since CONNECT-enabled proxies can be abused as TCP relays very easily. If you want to allow CONNECT for more ports than this, or want to forbid CONNECT altogether, you can specify a comma separated list of ports and port ranges (the latter using dashes, with the minimum defaulting to 0 and max to 65K): +limit-connect{443} # This is the default and need no be specified. +limit-connect{80,443} # Ports 80 and 443 are OK. +limit-connect{-3, 7, 20-100, 500-} # Port less than 3, 7, 20 to 100 #and above 500 are OK. * "+no-compression" prevents the website from compressing the data. Some websites do this, which can be a problem for Junkbuster, since "+filter", "+no-popup" and "+gif-deanimate" will not work on compressed data. This will slow down connections to those websites, though. Default is "nocompression" is turned on. +nocompression * Prevent the website from reading cookies: +no-cookies-read * Prevent the website from setting cookies: +no-cookies-set * Filter the website through a built-in filter to disable those obnoxious JavaScript pop-up windows via window.open(), etc. The two alternative spellings are equivalent. +no-popup +no-popups * This action only applies if you are using a jarfile for saving cookies. It sends a cookie to every site stating that you do not accept any copyright on cookies sent to you, and asking them not to track you. Of course, this is a (relatively) unique header they could use to track you. +vanilla-wafer * This allows you to add an arbitrary cookie. It can be specified multiple times in order to add as many cookies as you like. +wafer{name=value} The meaning of any of the above is reversed by preceding the action with a "-", in place of the "+". Some examples: Turn off cookies by default, then allow a few through for specified sites: # Turn off all cookies { +no-cookies-read } { +no-cookies-set } # Execeptions to the above, sites that need cookies { -no-cookies-read } { -no-cookies-set } .javasoft.com .sun.com .yahoo.com .msdn.microsoft.com .redhat.com # Alternative way of saying the same thing {-no-cookies-set -no-cookies-read} .sourceforge.net .sf.net Now turn off "fast redirects", and then we allow two exceptions: # Turn them off! {+fast-redirects} # Reverse it for these two sites, which don't work right without it. {-fast-redirects} www.ukc.ac.uk/cgi-bin/wac\.cgi\? login.yahoo.com Turn on page filtering, with one exception for sourceforge: # Run everything through the default filter file (re_filterfile): {+filter} # But please don't re_filter code from sourceforge! {-filter} .cvs.sourceforge.net Now some URLs that we want "blocked", ie we won't see them. Many of these use regular expressions that will expand to match multiple URLs: # Blocklist: {+block} /.*/(.*[-_.])?ads?[0-9]?(/|[-_.].*|\.(gif|jpe?g)) /.*/(.*[-_.])?count(er)?(\.cgi|\.dll|\.exe|[?/]) /.*/(ng)?adclient\.cgi /.*/(plain|live|rotate)[-_.]?ads?/ /.*/(sponsor)s?[0-9]?/ /.*/_?(plain|live)?ads?(-banners)?/ /.*/abanners/ /.*/ad(sdna_image|gifs?)/ /.*/ad(server|stream|juggler)\.(cgi|pl|dll|exe) /.*/adbanners/ /.*/adserver /.*/adstream\.cgi /.*/adv((er)?ts?|ertis(ing|ements?))?/ /.*/banner_?ads/ /.*/banners?/ /.*/banners?\.cgi/ /.*/cgi-bin/centralad/getimage /.*/images/addver\.gif /.*/images/marketing/.*\.(gif|jpe?g) /.*/popupads/ /.*/siteads/ /.*/sponsor.*\.gif /.*/sponsors?[0-9]?/ /.*/advert[0-9]+\.jpg /Media/Images/Adds/ /ad_images/ /adimages/ /.*/ads/ /bannerfarm/ /grafikk/annonse/ /graphics/defaultAd/ /image\.ng/AdType /image\.ng/transactionID /images/.*/.*_anim\.gif # alvin brattli /ip_img/.*\.(gif|jpe?g) /rotateads/ /rotations/ /worldnet/ad\.cgi /cgi-bin/nph-adclick.exe/ /.*/Image/BannerAdvertising/ /.*/ad-bin/ /.*/adlib/server\.cgi /autoads/ _________________________________________________________________ Aliases Custom "actions", known to Junkbuster as "aliases", can be defined by combining other "actions". These can in turn be invoked just like the built-in "actions". Currently, an alias can contain any character except space, tab, "=", "{" or "}". But please use only "a"- "z", "0"-"9", "+", and "-". Alias names are not case sensitive, and must be defined before anything else in actionsfile! And there can only be one set of "aliases" of defined. Now let's define a few aliases: # Useful customer aliases we can use later. These must come first! {{alias}} +no-cookies = +no-cookies-set +no-cookies-read -no-cookies = -no-cookies-set -no-cookies-read fragile = -block -no-cookies -filter -fast-redirects -hide-refere r -no-popups shop = -no-cookies -filter -fast-redirects +imageblock = +block +image #For people who don't like to type too much: ;-) c0 = +no-cookies c1 = -no-cookies c2 = -no-cookies-set +no-cookies-read c3 = +no-cookies-set -no-cookies-read #... etc. Customize to your heart's content. Some examples using our "shop" and "fragile" aliases from above: # These sites are very complex and require # minimal interference. {fragile} .office.microsoft.com .windowsupdate.microsoft.com .nytimes.com # Shopping sites - still want to block ads. {shop} .quietpc.com .worldpay.com # for quietpc.com .jungle.com .scan.co.uk # These shops require pop-ups {shop -no-popups} .dabs.com .overclockers.co.uk _________________________________________________________________ The Filter File The filter file defines what filtering of web pages Junkbuster does. The default filter file is re_filterfile, located in the config directory. In this file, any document content, whether viewable text or embedded non-visible content, can be changed. This file uses regular expressions to alter or remove any string in the target page. Some examples from the included default re_filterfile: Stop web pages from displaying annoying messages in the status bar by deleting such references: # The status bar is for displaying link targets, not pointless buzzwo rds. # Again, check it out on http://www.airport-cgn.de/. s/status='.*?';*//ig Just for kicks, replace any occurrence of "Microsoft" with "MicroSuck": s/microsoft(?!.com)/MicroSuck/ig Kill those auto-refresh tags: # Kill refresh tags. I like to refresh myself. Manually. # check it out on http://www.airport-cgn.de/ and go to the arrivals p age. # s/]*http-equiv[^>]*refresh.*URL=([^>]*?)"?>//i s/]*http-equiv="?page-enter"?[^>]*content=[^>]*>//i _________________________________________________________________ Quickstart to Using Junkbuster Install package, then run and enjoy! Junbuster accepts only one command line option -- the configuration file to be used. Example Unix startup command: # /usr/sbin/junkbuster /etc/junkbuster/config & If no configuration file is specified on the command line, Junkbuster will look for a file named config in the current directory. Except on Amiga where it will look for AmiTCP:db/junkbuster/config and Win32 where it will try junkbstr.txt. If no file is specified on the command line and no default configuration file can be found, Junkbuster will fail to start. Be sure your browser is set to use the proxy which is by default at localhost, port 8000. With Netscape (and Mozilla), this can be set under Edit -> Preferences -> Advanced -> Proxies -> HTTP Proxy. For Internet Explorer: Tools > Internet Properties -> Connections -> LAN Setting. Then, check "Use Proxy" and fill in the appropriate info (Address: localhost, Port: 8000). Include if HTTPS proxy support too. The included default configuration files should give a reasonable starting point, though may be somewhat aggressive in blocking junk. You will probably want to keep an eye out for sites that require cookies, and add these to actionsfile as needed. By default, most of these will be blocked until you add them to the configuration. If you want the browser to handle this instead, you will need to edit actionsfile and disable this feature. If you use more than one browser, it would make more sense to let Junkbuster handle this. In which case, the browser(s) should be set to accept all cookies. If a particular site shows problems loading properly, try adding it to the {fragile} section of actionsfile. This will turn off most actions for this site. HTTP/1.1 support is not fully implemented. If browsers that support HTTP/1.1 (like Mozilla or recent versions of I.E.) experience problems, you might try to force HTTP/1.0 compatiblity. For Mozilla, look under Edit -> Preferences -> Debug -> Networking. Or set the "+downgrade" config option in actionsfile. After running Junkbuster for a while, you can start to fine tune the configuration to suit your personal, or site, preferences and requirements. There are many, many aspects that can be customized. If you encounter problems, please verify it is a Junkbuster bug, by disabling Junkbuster, and then trying the same page. Also, try another browser if possible to eliminate browser or site problems. Before reporting it as a bug, see if there is not a configuration option that is enabled that is causing the page not to load. You can then add an exception for that page or site. If a bug, please report it to the developers (see below). _________________________________________________________________ Contact the Developers Feature requests and other questions should be posted to the [19]Feature request page at SourceForge. There is also an archive there. Anyone interested in actively participating in development and related discussions can join the appropriate mailing list [20]here. Archives are available here too. Please report bugs, using the form at [21]Sourceforge. Please try to verify that it is a Junkbuster bug, and not a browser or site bug first. Also, check to make sure this is not already a known bug. _________________________________________________________________ Copyright and History License Internet Junkbuster is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details, which is available from [22]the Free Software Foundation, Inc, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. _________________________________________________________________ History Junkbuster was originally written by Anonymous Coders and [23]JunkBusters Corporation, and was released as free open-source software under the GNU GPL. [24]Stefan Waldherr made many improvements, and started the [25]SourceForge project to rekindle development. The last stable release was v2.0.2, which has now grown whiskers ;-). _________________________________________________________________ See also [26]http://sourceforge.net/projects/ijbswa [27]http://ijbswa.sourceforge.net/ [28]http://ijbswa.sourceforge.net/config/ [29]http://www.junkbusters.com/ht/en/cookies.html [30]http://www.waldherr.org/junkbuster/ [31]http://privacy.net/analyze/ [32]http://www.squid-cache.org/ _________________________________________________________________ Appendix Regular Expressions Junkbuster can use "regular expressions" in various config files. Assuming support for "pcre" (Perl Compatible Regular Expressions) is compiled in, which is the default. Such configuration directives do not require regular expressions, but they can be used to increase flexibility by matching a pattern with wildcards against URLs. If you are reading this, you probably don't understand what "regular expressions" are, or what they can do. So this will be a very brief introduction only. A full explanation would require a book ;-) "Regular expressions" is a way of matching one character expression against another to see if it matches or not. One of the "expressions" is a literal string of readable characters (letter, numbers, etc), and the other is a complex string of literal characters combined with wildcards, and other special characters, called metacharacters. The "metacharacters" have special meanings and are used to build the complex pattern to be matched against. Perl Compatible Regular Expressions is an enhanced form of the regular expression language with backward compatibility. To make a simple analogy, we do something similar when we use wildcard characters when listing files with the dir command in DOS. *.* matches all filenames. The "special" character here is the asterik which matches any and all characters. We can be more specific and use ? to match just individual characters. So "dir file?.text" would match "file1.txt", "file2.txt", etc. We are pattern matching, using a similar technique to "regular expressions"! Regular expressions do essentially the same thing, but are much, much more powerful. There are many more "special characters" and ways of building complex patterns however. Let's look at a few of the common ones, and then some examples: . - Matches any single character, e.g. "a", "A", "4", ":", or "@". ? - The preceding character or expression is matched ZERO or ONE times. Either/or. + - The preceding character or expression is matched ONE or MORE times. * - The preceding character or expression is matched ZERO or MORE times. \ - The "escape" character denotes that the following character should be taken literally. This is used where one of the special characters (e.g. ".") needs to be taken literally and not as a special metacharacter. [] - Characters enclosed in brackets will be matched if any of the enclosed characters are encountered. () - Pararentheses are used to group a sub-expression, or multiple sub-expressions. | - The "bar" character works like an "or" conditional statement. A match is successful if the sub-expression on either side of "|" matches. s/string1/string2/g - This is used to rewrite strings of text. "string1" is replaced by "string2" in this example. These are just some of the ones you are likely to use when matching URLs with Junkbuster, and is a long way from a definitive list. This is enough to get us started with a few simple examples which may be more illuminating: /.*/banners/.* - A simple example that uses the common combination of "." and "*" to denote any character, zero or more times. In other words, any string at all. So we start with a literal forward slash, then our regular expression pattern (".*") another literal forward slash, the string "banners", another forward slash, and lastly another ".*". We are building a directory path here. This will match any file with the path that has a directory named "banners" in it. The ".*" matches any characters, and this could conceivably be more forward slashes, so it might expand into a much longer looking path. For example, this could match: "/eye/hate/spammers/banners/annoy_me_please.gif", or just "/banners/annoying.html", or almost an infinite number of other possible combinations, just so it has "banners" in the path somewhere. A now something a little more complex: /.*/adv((er)?ts?|ertis(ing|ements?))?/ - We have several literal forward slashes again ("/"), so we are building another expression that is a file path statement. We have another ".*", so we are matching against any conceivable sub-path, just so it matches our expression. The only true literal that must match our pattern is adv, together with the forward slashes. What comes after the "adv" string is the interesting part. Remember the "?" means the preceding expression (either a literal character or anything grouped with "(...)" in this case) can exist or not, since this means either zero or one match. So "((er)?ts?|ertis(ing|ements?))" is optional, as are the individual sub-expressions: "(er)", "(ing|ements?)", and the "s". The "|" means "or". We have two of those. For instance, "(ing|ements?)", can expand to match either "ing" OR "ements?". What is being done here, is an attempt at matching as many variations of "advertisement", and similar, as possible. So this would expand to match just "adv", or "advert", or "adverts", or "advertising", or "advertisement", or "advertisements". You get the idea. But it would not match "advertizements" (with a "z"). We could fix that by changing our regular expression to: "/.*/adv((er)?ts?|erti(s|z)(ing|ements?))?/", which would then match either spelling. /.*/advert[0-9]+\.(gif|jpe?g) - Again another path statement with forward slashes. Anything in the square brackets "[]" can be matched. This is using "0-9" as a shorthand expression to mean any digit one through nine. It is the same as saying "0123456789". So any digit matches. The "+" means one or more of the preceding expression must be included. The preceding expression here is what is in the square brackets -- in this case, any digit one through nine. Then, at the end, we have a grouping: "(gif|jpe?g)". This includes a "|", so this needs to match the expression on either side of that bar character also. A simple "gif" on one side, and the other side will in turn match either "jpeg" or "jpg", since the "?" means the letter "e" is optional and can be matched once or not at all. So we are building an expression here to match image GIF or JPEG type image file. It must include the literal string "advert", then one or more digits, and a "." (which is now a literal, and not a special character, since it is escaped with "\"), and lastly either "gif", or "jpeg", or "jpg". Some possible matches would include: "//advert1.jpg", "/nasty/ads/advert1234.gif", "/banners/from/hell/advert99.jpg". It would not match "advert1.gif" (no leading slash), or "/adverts232.jpg" (the expression does not include an "s"), or "/advert1.jsp" ("jsp" is not in the expression anywhere). s/microsoft(?!.com)/MicroSuck/i - This is a substitution. "MicroSuck" will replace any occurence of "microsoft". The "i" at the end of the expression means ignore case. The "(?!.com)" means the match should fail if "microsoft" is followed by ".com". In other words, this acts like a "NOT" modifier. In case this is a hyperlink, we don't want to break it ;-). We are barely scratching the surface of regular expressions here so that you can understand the default Junkbuster configuration files, and maybe use this knowledge to customize your own installation. There is much, much more that can be done with regular expressions. Now that you know enough to get started, you can learn more on your own :/ More reading on Perl Compatible Regular expressions: [33]http://www.perldoc.com/perl5.6/pod/perlre.html Done. References 1. http://ijbswa.sourceforge.net/doc/user-manual/ 2. file://localhost/home/hal/junkbuster/current/doc/source/tmp.html#INTRODUCTION 3. file://localhost/home/hal/junkbuster/current/doc/source/tmp.html#INSTALLATION 4. file://localhost/home/hal/junkbuster/current/doc/source/tmp.html#CONFIGURATION 5. file://localhost/home/hal/junkbuster/current/doc/source/tmp.html#QUICKSTART 6. file://localhost/home/hal/junkbuster/current/doc/source/tmp.html#CONTACT 7. file://localhost/home/hal/junkbuster/current/doc/source/tmp.html#COPYRIGHT 8. file://localhost/home/hal/junkbuster/current/doc/source/tmp.html#SEEALSO 9. file://localhost/home/hal/junkbuster/current/doc/source/tmp.html#APPENDIX 10. http://sourceforge.net/projects/ijbswa/ 11. http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/ijbswa/current/ 12. http://hobbes.nmsu.edu/cgi-bin/h-search?sh=1&button=Search&key=emxrt.zip&stype=all&sort=type&dir=%2Fpub%2Fos2%2Fdev%2Femx%2Fv0.9d 13. http://hobbes.nmsu.edu/cgi-bin/h-search?sh=1&key=gnupack&stype=all&sort=type&dir=%2Fpub%2Fos2%2Fapps 14. http://www.gnu.org/ 15. file://localhost/home/hal/junkbuster/current/doc/source/tmp.html#ACTIONSFILE 16. http://i.j.b/show-url-info 17. http://www.perldoc.com/perl5.6/pod/perlre.html 18. file://localhost/home/hal/junkbuster/current/doc/source/tmp.html#REGEX 19. http://sourceforge.net/tracker/?atid=361118&group_id=11118&func=browse 20. http://sourceforge.net/mail/?group_id=11118 21. http://sourceforge.net/tracker/?group_id=11118&atid=111118 22. http://www.gnu.org/copyleft/gpl.html 23. http://www.junkbusters.com/ht/en/ijbfaq.html 24. http://www.waldherr.org/junkbuster/ 25. http://sourceforge.net/projects/ijbswa/ 26. http://sourceforge.net/projects/ijbswa 27. http://ijbswa.sourceforge.net/ 28. http://ijbswa.sourceforge.net/config/ 29. http://www.junkbusters.com/ht/en/cookies.html 30. http://www.waldherr.org/junkbuster/ 31. http://privacy.net/analyze/ 32. http://www.squid-cache.org/ 33. http://www.perldoc.com/perl5.6/pod/perlre.html