Nit.

[privoxy.git] / doc / text / user-manual.txt

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  [<ip-address>]:<port>".  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 <domain>/<path>, where both the
   <domain>  and  <path>  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/<meta[^>]*http-equiv[^>]*refresh.*URL=([^>]*?)"?>/<link rev="x-refr
   esh" href=$1>/i
    s/<meta[^>]*http-equiv="?page-enter"?[^>]*content=[^>]*>/<!--no page
   enter for me-->/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