#! /usr/bin/perl -w
#
# Explain to the user that the URL is blocked and by which rule set
#
# By Pål Baltzersen 1999 (pal.baltzersen@ost.eltele.no)
# French texts thanks to Fabrice Prigent (fabrice.prigent@univ-tlse1.fr)
# Dutch texts thanks to Anneke Sicherer-Roetman (sicherer@sichemsoft.nl)
# German texts thanks to Buergernetz Pfaffenhofen (http://www.bn-paf.de/filter/)
#
# The last version may be found anytime at:
#    http://ftp.your-domain/pub/www/proxy/squidGuard/contrib/
#

# By accepting this notice, you agree to be bound by the following
# agreements:
# 
# This software product, squidGuard, is copyrighted (C) 1999 by ElTele
# Øst AS, Oslo, Norway, with all rights reserved.
# 
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License (version 2) as
# published by the Free Software Foundation.  It 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 (GPL) for more details.
# 
# You should have received a copy of the GNU General Public License
# (GPL) along with this program.

use strict;
use Socket;
#
# GLOBAL VALUES:
#
my ($clientaddr,$clientname,$clientuser,$clientgroup,$targetgroup,$url);
my ($lang,@supported,$image,$redirect,$autoinaddr,$proxy,$proxymaster);
my (%msgconf,%title,%logo,%msg,%tab,%word);
my ($protocol,$address,$port,$path,$refererhost,$referer);
sub msginit();
sub getpreferedlang(@);
sub parsequery($);
sub status($);
sub redirect($);
sub content($);
sub expires($);
sub title($);
sub terminator();
sub msg($$);
sub table($$@);
sub href($);
sub gethostnames($);
sub spliturl($);
sub showhtml($);
sub showimage($$$);
sub showinaddr($$$$$);

#
# CONFIGURABLE OPTIONS:
#
@supported   = (							# "en", "fr", "de", "nl", "no" etc.
		"en (English),",
		"fr (Français),",
		"de (Deutsch),",
		"nl (Nederlands),",
		"no (norsk)."
	       );
$image       = "/images/blocked.gif";					# RELATIVE TO DOCUMENT_ROOT
$redirect    = "http://admin.your-domain/images/blocked.gif";		# "" TO AVOID REDIRECTION
$proxy       = "proxy.your-domain";					#
$proxymaster = "operator\@your-domain";				#
$autoinaddr  = 2;			# 0|1|2;
					# 0 TO NOT REDIRECT
					# 1 TO AUTORESOLVE & REDIRECT IF UNIQUE
					# 2 TO AUTORESOLVE & REDIRECT TO FIRST NAME
#
# CONFIGURABLE MESSAGES:
#
# !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
# !!! NOTE1: ALLWAYS ESCAPE EMBEDDED VARIABLES (I.E. \$var)         !!!
# !!!	     IF YOU DON'T YOU MAY OPEN A SECURITY HOLE	            !!!
# !!! NOTE2: TRIPLE ESCAPE EMBEDDED `\', `"', `$', `@', `%' and `&' !!!
# !!!	     (I.E. \\\\, \\\", \\\$, \\\@, \\\&)	            !!!
# !!! NOTE3: ESCAPE OTHER SPECIAL INLINE CHARACTERS	            !!!
# !!!	     (I.E. \;, \')				            !!!
# !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
#
sub msginit() {
  ($clientaddr,$clientname,$clientuser,$clientgroup,$targetgroup,$url)
    = parsequery($ENV{"QUERY_STRING"});
  ($protocol,$address,$port,$path) = spliturl($url);
  $lang = getpreferedlang(@supported);

  %word->{"unknown"}->{"en"}		# THE WORD "unknown"
    = "unknown";			# --------- "" ---------
  %word->{"unknown"}->{"fr"}		# "unknown" IN FRENCH
    = "inconnu";			# 
  %word->{"unknown"}->{"de"}		# "unknown" IN GERMAN
    = "unbekannt";			# 
  %word->{"unknown"}->{"nl"}		# "unknown" IN DUTCH
    = "onbekend";			# 
  %word->{"unknown"}->{"no"}		# "unknown" IN NORWEGIAN
    = "ukjent";				# 

  %title->{"default"}->{"en"}		# THE DEFAULT TITLE
    = [ "403 Forbidden" ];		# --------- "" ---------
  %title->{"default"}->{"fr"}		# --------- "" ---------
    = [ "403 Interdit" ];		# --------- "" ---------
  %title->{"default"}->{"de"}		# --------- "" ---------
    = [ "403 Verboten" ];		# --------- "" ---------
  %title->{"default"}->{"nl"}		# --------- "" ---------
    = [ "403 Verboden" ];		# --------- "" ---------
  %title->{"default"}->{"no"}		# --------- "" ---------
    = [ "403 Sperret" ];		# --------- "" ---------

  %msgconf->{"default"}			# THE "default" MESSAGE CONFIG
    					# (USED WHEN NO OTHER MSGS APPLIES):
    = [ "msg:H1:default",		# SHOW MSG "default" AS <H1> (DEFINED BELOW)
	"tab:R,C,L:info"		# SHOW "info" AS <TABLE> & COLUMNS ALIGNED R,C,L
	. ":clientaddr"			# AND WITH THESE ELEMENTS (DEFINED BELOW)
	. ":clientname"			# --------- "" --------- "" --------- 
	. ":clientuser"			# --------- "" --------- "" --------- 
	. ":clientgroup"		# --------- "" --------- "" --------- 
	. ":url"			# --------- "" --------- "" --------- 
	. ":targetgroup",		# --------- "" --------- "" --------- 
	"msg:P:proxymaster",		# SHOW "proxymaster" AS <P> (DEFINED BELOW)
	"msg:P:refresh"			# SHOW "refresh" AS <P> (DEFINED BELOW)
      ];

  %msgconf->{"unknown"}			# THE "unknown" CLIENT MESSAGE CONFIG:
    = [ "msg:H1:unknown",		# SHOW "unknown" AS <H1> (DEFINED BELOW)
	"tab:R,C,L:info"		# SHOW "info" AS <TABLE> & COLUMNS ALIGNED R,C,L
	. ":clientaddr"			# AND WITH THESE ELEMENTS (DEFINED BELOW)
	. ":clientname"			# --------- "" --------- "" ---------
	. ":clientuser"			# --------- "" --------- "" ---------
	. ":clientgroup",		# --------- "" --------- "" ---------
	"msg:P:proxymaster",		# SHOW "proxymaster" AS <P> (DEFINED BELOW)
	"msg:P:refresh"			# SHOW "refresh" AS <P> (DEFINED BELOW)
      ];
  %msgconf->{%word->{"unknown"}->{$lang}}
    = %msgconf->{"unknown"};

  %msgconf->{"in-addr"}			# THE MESSAGE CONFIG FOR THE "in-addr" DEST GROUP:
    = [ "msg:H1:alternatives",		# SHOW "alternatives" AS <H1> (DEFINED BELOW)
	"alternatives",			# SHOW THE ALTERNATIV DOMAIN ADDRESSES
	"referermaster",		# SHOW "referermaster" (DEFINED BELOW)
	"msg:P:refresh"			# SHOW "refresh" AS <P> (DEFINED BELOW)
      ];
  
  %msgconf->{"noalternatives"}		# DITTO WHEN THERE ARE NO DOMAIN ADDRESS ALTERNATIVES:
    = [ "msg:H1:in-addr",		# SHOW "in-addr" AS <H1> (DEFINED BELOW)
	"tab:R,C,L:info"		# SHOW "info" AS <TABLE> & COLUMNS ALIGNED R,C,L
	. ":clientaddr"			# AND WITH THESE ELEMENTS (DEFINED BELOW)
	. ":clientname"			# --------- "" --------- "" ---------
	. ":clientuser"			# --------- "" --------- "" ---------
	. ":clientgroup"		# --------- "" --------- "" ---------
	. ":domainurl"			# --------- "" --------- "" ---------
	. ":targetgroup",		# --------- "" --------- "" ---------
	"msg:H3:noalternatives",	# SHOW "noalternatives" AS <H3> (DEFINED BELOW)
	"msg:P:webmaster",		# SHOW "webmaster" AS <P> (DEFINED BELOW)
	"msg:P:refresh"			# SHOW "refresh" AS <P> (DEFINED BELOW)
      ];
  
  %msg->{"default"}->{"en"}			# THE MSG TEXT "default" IN "en" (ENGLISH):
    = [ "Access to this site is blocked" ];	#
  %msg->{"default"}->{"fr"}			# THE MSG TEXT "default" IN "fr" (FRENCH):
    = [ "L\'accès à ce site est bloqué" ];	#
  %msg->{"default"}->{"de"}			# THE MSG TEXT "default" IN "de" (GERMAN):
    = [ "Zugriff verweigert" ];			#
  %msg->{"default"}->{"nl"}			# THE MSG TEXT "default" IN "nl" (DUTCH):
    = [ "De toegang is geblokkeerd" ];          #
  %msg->{"default"}->{"no"}			# THE MSG TEXT "default" IN "no" (NORWEGIAN):
    = [ "Siden er sperret" ];			#

						# THE "info" TABLE IN "en" (ENGLISH):
  %tab->{"info"}->{"caption"}->{"en"}		# THE "info" TABLE'S TITLE:
    = [ "Additional information:" ];		#
  %tab->{"info"}->{"clientaddr"}->{"en"}	# THE "clientaddr" MSG OPTION:
    = [ "Client address", "=", "\$clientaddr" ];#
  %tab->{"info"}->{"clientname"}->{"en"}	# THE "clientname" MSG OPTION:
    = [ "Client name", "=", "\$clientname" ];	#
  %tab->{"info"}->{"clientuser"}->{"en"}	# THE "clientuser" MSG OPTION:
    = [ "Client user", "=", "\$clientuser" ];	#
  %tab->{"info"}->{"clientgroup"}->{"en"}	# THE "clientgroup" MSG OPTION:
    = [ "Client group", "=", "\$clientgroup" ];	#
  %tab->{"info"}->{"url"}->{"en"}		# THE "url" MSG OPTION:
    = [ "URL", "=", "\$url" ];			#
  %tab->{"info"}->{"domainurl"}->{"en"}		# THE "domainurl" MSG OPTION:
    = [ "URL", "=", "\$protocol://<U>\$address</U>\$port\$path" ];
  %tab->{"info"}->{"targetgroup"}->{"en"}	# THE "targetgroup" MSG OPTION:
    = [ "Target group", "=", "\$targetgroup" ];	#

  %tab->{"info"}->{"caption"}->{"fr"}		# DITTO IN "fr" (FRENCH):
    = [ "Information complémentaire:" ];	# --------- "" ---------
  %tab->{"info"}->{"clientaddr"}->{"fr"}	# --------- "" ---------
    = [ "Adresse de la machine", "=", "\$clientaddr" ];
  %tab->{"info"}->{"clientname"}->{"fr"}	# --------- "" ---------
    = [ "Nom de la machine", "=", "\$clientname" ];
  %tab->{"info"}->{"clientuser"}->{"fr"}	# --------- "" ---------
    = [ "Utilisateur", "=", "\$clientuser" ];	# --------- "" ---------
  %tab->{"info"}->{"clientgroup"}->{"fr"}	# --------- "" ---------
    = [ "Groupe", "=", "\$clientgroup" ];	# --------- "" ---------
  %tab->{"info"}->{"url"}->{"fr"}		# --------- "" ---------
    = [ "URL", "=", "\$url" ];			# --------- "" ---------
  %tab->{"info"}->{"domainurl"}->{"fr"}		# --------- "" ---------
    = [ "URL", "=", "\$protocol://<U>\$address</U>\$port\$path" ];
  %tab->{"info"}->{"targetgroup"}->{"fr"}	# --------- "" ---------
    = [ "Groupe cible", "=", "\$targetgroup" ];	# --------- "" ---------
  
  %tab->{"info"}->{"caption"}->{"de"}		# DITTO IN "de" (GERMAN):
    = [ "Zusatzinformationen:" ];		# --------- "" ---------
  %tab->{"info"}->{"clientaddr"}->{"de"}	# --------- "" ---------
    = [ "IP-Adresse", "=", "\$clientaddr" ];	# --------- "" ---------
  %tab->{"info"}->{"clientname"}->{"de"}	# --------- "" ---------
    = [ "Rechnername", "=", "\$clientname" ];	# --------- "" ---------
  %tab->{"info"}->{"clientuser"}->{"de"}	# --------- "" ---------
    = [ "Benutzer", "=", "\$clientuser" ];	# --------- "" ---------
  %tab->{"info"}->{"clientgroup"}->{"de"}	# --------- "" ---------
    = [ "Gruppe", "=", "\$clientgroup" ];	# --------- "" ---------
  %tab->{"info"}->{"url"}->{"de"}		# --------- "" ---------
    = [ "URL", "=", "\$url" ];			# --------- "" ---------
  %tab->{"info"}->{"domainurl"}->{"de"}		# --------- "" ---------
    = [ "URL", "=", "\$protocol://<U>\$address</U>\$port\$path" ];
  %tab->{"info"}->{"targetgroup"}->{"de"}	# --------- "" ---------
    = [ "Klassifizierung", "=", "\$targetgroup" ];
  
  %tab->{"info"}->{"caption"}->{"nl"}		# DITTO IN "nl" (DUTCH):
    = [ "Extra informatie:" ];			# --------- "" ---------
  %tab->{"info"}->{"clientaddr"}->{"nl"}	# --------- "" ---------
    = [ "Computeradres", "=", "\$clientaddr" ];	# --------- "" ---------
  %tab->{"info"}->{"clientname"}->{"nl"}	# --------- "" ---------
    = [ "Computernaam", "=", "\$clientname" ];	# --------- "" ---------
  %tab->{"info"}->{"clientuser"}->{"nl"}	# --------- "" ---------
    = [ "Gebruiker", "=", "\$clientuser" ];	# --------- "" ---------
  %tab->{"info"}->{"clientgroup"}->{"nl"}	# --------- "" ---------
    = [ "Groep", "=", "\$clientgroup" ];	# --------- "" ---------
  %tab->{"info"}->{"url"}->{"nl"}		# --------- "" ---------
    = [ "URL", "=", "\$url" ];			# --------- "" ---------
  %tab->{"info"}->{"domainurl"}->{"nl"}		# --------- "" ---------
    = [ "URL", "=", "\$protocol://<U>\$address</U>\$port\$path" ];
  %tab->{"info"}->{"targetgroup"}->{"nl"}	# --------- "" ---------
    = [ "Doelgroep", "=", "\$targetgroup" ];	# --------- "" ---------

  %tab->{"info"}->{"caption"}->{"no"}		# DITTO IN "no" (NORWEGIAN):
    = [ "Tilleggsinformasjon:" ];		# --------- "" ---------
  %tab->{"info"}->{"clientaddr"}->{"no"}	# --------- "" ---------
    = [ "Klientadresse", "=", "\$clientaddr" ];	# --------- "" ---------
  %tab->{"info"}->{"clientname"}->{"no"}	# --------- "" ---------
    = [ "Klientnavn", "=", "\$clientname" ];	# --------- "" ---------
  %tab->{"info"}->{"clientuser"}->{"no"}	# --------- "" ---------
    = [ "Brukerident", "=", "\$clientuser" ];	# --------- "" ---------
  %tab->{"info"}->{"clientgroup"}->{"no"}	# --------- "" ---------
    = [ "Klientgruppe", "=", "\$clientgroup" ];	# --------- "" ---------
  %tab->{"info"}->{"url"}->{"no"}		# --------- "" ---------
    = [ "URL", "=", "\$url" ];			# --------- "" ---------
  %tab->{"info"}->{"domainurl"}->{"no"}		# --------- "" ---------
    = [ "URL", "=", "\$protocol://<U>\$address</U>\$port\$path" ];
  %tab->{"info"}->{"targetgroup"}->{"no"}	# --------- "" ---------
    = [ "Målkategori", "=", "\$targetgroup" ];	# --------- "" ---------

  %msg->{"proxymaster"}->{"en"}
    = [ "If you think this is an error, send <U>this page</U> to",
	"<A HREF=\\\"mailto:\$proxymaster\\\">\$proxymaster</A>" ];
  %msg->{"proxymaster"}->{"fr"}
    = [ "Si vous pensez qu\'il s\'agit d\'une erreur, envoyez <U>cette page</U> à",
	"<A HREF=\\\"mailto:\$proxymaster\\\">\$proxymaster</A>" ];
  %msg->{"proxymaster"}->{"de"}
    = [ "Falls ein Fehler vorliegt schicken Sie die Adresse <U>dieser Seite</U> bitte an",
	"<A HREF=\\\"mailto:\$proxymaster\\\">\$proxymaster</A>" ];
  %msg->{"proxymaster"}->{"nl"}
    = [ "Als u denkt dat dit onjuist is, zend <U>deze bladzijde</U> aan",
	"<A HREF=\\\"mailto:\$proxymaster\\\">\$proxymaster</A>" ];
  %msg->{"proxymaster"}->{"no"}
    = [ "Om du mener dette er feil, så send <U>denne siden</U> til",
	"<A HREF=\\\"mailto:\$proxymaster\\\">\$proxymaster</A>" ];

  %msg->{"refresh"}->{"en"}
    = [ "You may need to use the browser's \&lt\;Reload\&gt\; button<BR>",
	"or even \&lt\;Keyboard Shift\&gt\;+\&lt\;Browser Reload\&gt\;<BR>",
	"to get rid of this page after an access rule change" ];
  %msg->{"refresh"}->{"fr"}
    = [ "Vous avez peut-être besoin d\'utiliser le bouton \&lt\;Recharger\&gt\;<BR>",
	"ou même \&lt\;Shift\&gt\;+\&lt\;Recharger\&gt\;<BR>",
	"après un changement de règles" ];
  %msg->{"refresh"}->{"de"}
    = [ "Nach einer &Auml;nderung der Zugriffsrechte m&uuml;ssen Sie evtl. die Seite<BR>",
	"mit dem \&lt\;Aktualisieren\&gt\; bzw. \&lt\;Neu laden\&gt\; Button<BR>",
	"des Browsers oder sogar mit \&lt\;Strg\&gt\;+\&lt\;F5\&gt\;<BR>",
	"erneut laden lassen." ];
  %msg->{"refresh"}->{"nl"}
    = [ "U moet waarschijnlijk de browser's \&lt\;Reload\&gt\; knop gebruiken<BR>",
	"of zelfs \&lt\;Shift\&gt\;+\&lt\;Reload\&gt\;<BR>",
	"na een verandering in de squidGuard regels" ];
  %msg->{"refresh"}->{"no"}
    = [ "Du kan trenge å bruke browserens \&lt\;Reload\&gt\; knapp<BR>",
	"eller til og med",
	"\&lt\;Tastatur Shift\&gt\;+\&lt\;Browser Reload\&gt\;<BR>",
	"for å bli kvitt denne siden etter endring i adgangskontrollen" ];
  
  %msg->{"timerefresh"}->{"en"}
    = [ "You may need to use the browser's \&lt\;Reload\&gt\; button<BR>",
	"or even \&lt\;Keyboard Shift\&gt\;+\&lt\;Browser Reload\&gt\;<BR>",
	"to get rid of this page after transition from<BR>",
	"a time zone with access restrictions" ];
  %msg->{"timerefresh"}->{"fr"}
    = [ "Vous avez peut-être besoin d\'utiliser le bouton \&lt\;Recharger\&gt\;<BR>",
	"ou même \&lt\;Shift\&gt\;+\&lt\;Recharger\&gt\;<BR>",
	"après un changement de zone temporelle d\'interdiction" ];
  %msg->{"timerefresh"}->{"de"}
    = [ "Nach dem Wechsel in eine erlaubte Zeitperiode m&uuml;ssen Sie evtl. die Seite<BR>",
	"mit dem \&lt\;Aktualisieren\&gt\; bzw. \&lt\;Neu laden\&gt\; Button des Browsers<BR>",
	"oder sogar mit \&lt\;Strg\&gt\;+\&lt\;F5\&gt\; erneut laden lassen." ];
  %msg->{"timerefresh"}->{"nl"}
    = [ "U moet waarschijnlijk de browser's \&lt\;Reload\&gt\; knop gebruiken<BR>",
	"of zelfs \&lt\;Shift\&gt\;+\&lt\;Reload\&gt\;<BR>",
	"na beeindiging van een periode met beperkingen" ];
  %msg->{"timerefresh"}->{"no"}
    = [ "Du kan trenge å bruke browserens \&lt\;Reload\&gt\; knapp<BR>",
	"eller til og med",
	"\&lt\;Tastatur Shift\&gt\;+\&lt\;Browser Reload\&gt\;<BR>",
	"for å bli kvitt denne siden ved overgang fra",
	"et tidsrom med sperring" ];
  
  %msg->{"unknown"}->{"en"}
    = [ "Access denied because<BR>",
	"your clienten is<BR>",
	"unknown to \$proxy"];
  %msg->{"unknown"}->{"fr"}
    = [ "Accès interdit car <BR>",
	"votre client est <BR>",
	"inconnu de \$proxy"];
  %msg->{"unknown"}->{"de"}
    = [ "Zugriff verweigert,<BR>",
	"da Ihr Rechner bei<BR>",
	"\$proxy unbekannt ist."];
  %msg->{"unknown"}->{"nl"}
    = [ "Toegand geweigerd omdat <BR>",
	"uw client niet <BR>",
	"bekend is bij \$proxy"];
  %msg->{"unknown"}->{"no"}
    = [ "Adgang nektes fordi<BR>",
	"denne klienten ikke er<BR>",
	"definert på \$proxy" ];
  
  %msg->{"in-addr"}->{"en"}
    = [ "Surfing on plain <U>IP-addresses</U><BR>",
	"is denied from this client<BR>",
	"for security reasons" ];
  %msg->{"in-addr"}->{"fr"}
    = [ "Naviguer sur des <U>adresses IP</U><BR>",
	"est refusé à cette machine<BR>",
	"pour des raisons de sécurité" ];
  %msg->{"in-addr"}->{"de"}
    = [ "Die direkte Verwendung von <U>IP-Adressen</U><BR>",
	"ist von diesem Rechner aus Sicherheitsg&uuml;nden<BR>",
	"nicht erlaubt." ];
  %msg->{"in-addr"}->{"nl"}
    = [ "Surfen naar harde <U>IP adressen</U><BR>",
	"wordt op deze client geweigerd<BR>",
	"om veiligheidsredenen" ];
  %msg->{"in-addr"}->{"no"}
    = [ "Av sikkerhetsgrunner er<BR>",
	"surfing på <U>IP-adresser</U><BR>",
	"ikke tillatt fra denne klienten" ];
  
  %msg->{"alternatives"}->{"en"}
    = [ "The following possible alternatives were found:" ];
  %msg->{"alternatives"}->{"fr"}
    = [ "Les alternatives suivantes sont possibles:" ];
  %msg->{"alternatives"}->{"de"}
    = [ "Die folgenden Alternativen wurden gefunden:" ];
  %msg->{"alternatives"}->{"nl"}
    = [ "De volgende alternatieven zijn mogelijk:" ];
  %msg->{"alternatives"}->{"no"}
    = [ "Følgende mulige alternativer ble funnet:" ];

  %msg->{"noalternatives"}->{"en"}
    = [ "No alternative domainname were found<BR>",
	"for the server <U>\$address</U>" ];
  %msg->{"noalternatives"}->{"fr"}
    = [ "Aucun nom de domaine alternatif n\'a été<BR>",
	"trouvé pour le serveur <U>\$address</U>" ];
  %msg->{"noalternatives"}->{"de"}
    = [ "Es konnte kein alternativer Domainname f&uuml;r den<BR>",
	"Server <U>\$address</U> gefunden werden" ];
  %msg->{"noalternatives"}->{"nl"}
    = [ "Geen alternatieve domeinnaam gevonden<BR>",
	"voor de server <U>\$address</U>" ];
  %msg->{"noalternatives"}->{"no"}
    = [ "Finner ingen alternative domenenavn<BR>",
	" for serveren <U>\$address</U>" ];

  %msg->{"referermaster"}->{"en"}
    = [ "Send complaints to the",
	"<A HREF=\\\"mailto:webmaster\@\$refererhost\\\">webmaster</A><BR>",
	"of <A HREF=\\\"\$referer\\\">\$referer</A><BR>",
	"and ask him to correct the link(s) that points to \$url<BR>",
	"in <A HREF=\\\"\$referer\\\">\$referer</A>,<BR>",
	"with the supposedly correct alternative above" ];
  %msg->{"referermaster"}->{"fr"}
    = [ "Envoyez les demandes au",
	"<A HREF=\\\"mailto:webmaster\@\$refererhost\\\">webmaster</A><BR>",
	"de <A HREF=\\\"\$referer\\\">\$referer</A><BR>",
	"et demandez lui corriger les liens qui pointent sur \$url<BR>",
	"dans <A HREF=\\\"\$referer\\\">\$referer</A>,<BR>",
	"avec l\'alternative (supposée correcte) suivante" ];
  %msg->{"referermaster"}->{"de"}
    = [ "Benachrichtigen Sie den",
	"<A HREF=\\\"mailto:webmaster\@\$refererhost\\\">Webmaster</A><BR>",
	"von <A HREF=\\\"\$referer\\\">\$referer</A><BR>",
	"und bitten Sie ihn die auf \$url verweisenden Links<BR>",
	"in <A HREF=\\\"\$referer\\\">\$referer</A>,<BR>",
	"auf die vermutlich korrekte oben angezeigte Alternative zu setzen." ];
  %msg->{"referermaster"}->{"nl"}
    = [ "Zend klachten aan",
	"<A HREF=\\\"mailto:webmaster\@\$refererhost\\\">webmaster</A><BR>",
	"de <A HREF=\\\"\$referer\\\">\$referer</A><BR>",
	"en vraag deze de link te verbeteren die verwijst naar \$url<BR>",
	"op <A HREF=\\\"\$referer\\\">\$referer</A>,<BR>",
	"met het waarschijnlijk correcte alternatief" ];
  %msg->{"referermaster"}->{"no"}
    = [ "Send evt. klager til",
	"<A HREF=\\\"mailto:webmaster\@\$refererhost\\\">webmaster</A><BR>",
	"for <A HREF=\\\"\$referer\\\">\$referer</A><BR>",
	"og be ham rette linken(e) som peker til \$url<BR>",
	"i <A HREF=\\\"\$referer\\\">\$referer</A>,<BR>",
	"med det antatt korrekte alternativet over" ];
  
  %msg->{"webmaster"}->{"en"}
    = [ "Send complaints to the <U>webmaster</U>",
	"for <U>\$protocol://\$address</U><BR>",
	"and request for a <EM>domainname</EM> to the server" ];
  %msg->{"webmaster"}->{"fr"}
    = [ "Envoyez les demandes au <U>webmaster</U>",
	"pour <U>\$protocol://\$address</U><BR>",
	"et demandez un <EM>nom de domaine</EM> pour le serveur" ];
  %msg->{"webmaster"}->{"de"}
    = [ "Fragen Sie den <U>Webmaster</U>",
	"von <U>\$protocol://\$address</U><BR>",
	"nach einem <EM>Domainnamen</EM> f&uuml;r den Server" ];
  %msg->{"webmaster"}->{"nl"}
    = [ "Stuur klachten aan de <U>webmaster</U>",
	"voor <U>\$protocol://\$address</U><BR>",
	"en vraag om een <EM>domeinnaam</EM> voor de server" ];
  %msg->{"webmaster"}->{"no"}
    = [ "Send evt. klager til <U>webmaster</U>",
	"for <U>\$protocol://\$address</U><BR>",
	"og anmod om å få knyttet serveren til et <EM>domenenavn</EM>" ];
  
  %msg->{"deflang"}->{"en"}
    = [ "This message is in English because \\\"en\\\"",
	"is the first supported language<BR>",
	"of those your browser is set up",
	"to report as prefered.<BR>",
	"Supported languages are:",
	@supported ];
  %msg->{"deflang"}->{"fr"}
    = [ "Ce message est en français car \\\"fr\\\"",
	"est la première langue supportée<BR>",
	"parmi celles que votre navigateur signale comme",
	"préférée.<BR>",
	"Les langues supportées sont:",
	@supported ];
  %msg->{"deflang"}->{"de"}
    = [ "Dieser Text erscheint in Deutsch, \\\"de\\\"",
	"da Ihr Browser dies als bevorzugte<BR>",
	"(erste) Sprache einstellt hat.<BR>",
	"Unterst&uuml;tzte Sprachen:",
	@supported ];
  %msg->{"deflang"}->{"nl"}
    = [ "Deze melding is in het Nederlands want \\\"nl\\\"",
	"is de eerst ondersteunde taal<BR>",
	"van de talen die uw browser ondersteunt.",
	"<BR>",
	"De ondersteunde talen zijn:",
	@supported ];
  %msg->{"deflang"}->{"no"}
    = [ "Denne meldingen er på norsk fordi \\\"no\\\"",
	"er det første støttede sproget<BR>",
	"av de din nettleser er satt opp til",
	"å rapportere som foretrukket.<BR>",
	"Støttede sprog er:",
	@supported ];
  
  %logo->{"default"}->{"url"}
    = "http://www.squidguard.org/images/squidGuard.gif";
  %logo->{"default"}->{"href"}
    = "http://www.squidguard.org/";

  %logo->{"default"}->{"url"}
    = "http://info.your-domain/images/eto.small.gif";
  %logo->{"default"}->{"href"}
    = "http://www.your-domain/";
}
#
# END OF CONFIGURABLE OPTIONS
#

#
# SUBROUTINES:
#

#
# RETURN THE FIRST SUPPORTED LANGUAGE OF THE BROWSERS PREFERRED OR THE
# DEFAULT:
#
sub getpreferedlang(@) {
  my @supported = @_;
  my @languages = split(/\s*,\s*/,$ENV{"HTTP_ACCEPT_LANGUAGE"}) if(defined($ENV{"HTTP_ACCEPT_LANGUAGE"}));
  my $lang;
  my $supp;
  push(@languages,$supported[0]);
  for $lang (@languages) {
    $lang =~ s/\s.*//;
    for $supp (@supported) {
      $supp =~ s/\s.*//;
      return($lang) if ($lang eq $supp);
    }
  }
}

#
# PARSE THE QUERY_STRING FOR KNOWN KEYS:
#
sub parsequery($) {
  my $query       = shift;
  my $clientaddr  = %word->{"unknown"}->{$lang};
  my $clientname  = %word->{"unknown"}->{$lang};
  my $clientuser  = %word->{"unknown"}->{$lang};
  my $clientgroup = %word->{"unknown"}->{$lang};
  my $targetgroup = %word->{"unknown"}->{$lang};
  my $url         = %word->{"unknown"}->{$lang};
  if (defined($query)) {
    while ($query =~ /^\&?([^\&=]+)=\"([^\"]*)\"(.*)/ || $query =~ /^\&?([^\&=]+)=([^\&=]*)(.*)/) {
      my $key = $1;
      my $value = $2;
      $value = %word->{"unknown"}->{$lang} unless(defined($value) && $value && $value ne "unknown");
      $query = $3;
      if ($key =~ /^(clientaddr|clientname|clientuser|clientgroup|targetgroup|url)$/) {
	eval "\$$key = \$value";
      }
      if ($query =~ /^url=(.*)/) {
	$url = $1;
	last;
      }
    }
  }
  return($clientaddr,$clientname,$clientuser,$clientgroup,$targetgroup,$url);
}

#
# PRINT HTTP STATUS HEARER:
#
sub status($) {
  my $status = shift;
  print "Status: $status\n";
}

#
# PRINT HTTP LOCATION HEARER:
#
sub redirect($) {
  my $location = shift;
  print "Location: $location\n";
}

#
# PRINT HTTP CONTENT-TYPE HEARER:
#
sub content($) {
  my $contenttype = shift;
  print "Content-Type: $contenttype\n";
}

#
# PRINT HTTP LAST-MODIFIED AND EXPIRES HEARER:
#
sub expires($) {
  my $ttl = shift;
  my $time = time;
  my @day = ("Sun","Mon","Tue","Wed","Thu","Fri","Sat");
  my @month = ("Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec");
  my ($sec,$min,$hour,$mday,$mon,$year,$wday) = gmtime($time);
  printf "Last-Modified: %s, %d %s %d", $day[$wday],$mday,$month[$mon],$year+1900;
  printf " %02d:%02d:%02d GMT\n", $hour,$min,$sec;
  ($sec,$min,$hour,$mday,$mon,$year,$wday) = gmtime($time+$ttl);
  printf "Expires: %s, %d %s %d", $day[$wday],$mday,$month[$mon],$year+1900;
  printf " %02d:%02d:%02d GMT\n", $hour,$min,$sec;
}

#
# PRINT THE INITIAL HTML TAGS FOR HTML, HEAD, TITLE BODY AND H1:
#
sub title($) {
  my $msgid = shift;
  my $defl  = $supported[0];
  my $text;
  $defl =~ s/\s.*//;
  print "\n<HTML>\n";
  print " <HEAD>\n  <TITLE>\n";
  if (defined($msg{$msgid}{$lang})) {
    for $text (@{$title{$msgid}{$lang}}) {
      eval "\$text = \"$text\"";
      print "       $text\n";
    }
  } else {
    for $text (@{$title{"default"}{$lang}}) {
      eval "\$text = \"$text\"";
      print "       $text\n";
    }
  }
  print "  </TITLE>\n </HEAD>\n";
  print " <BODY BGCOLOR=\"#FFFFFF\">\n";
  print "  <TABLE BORDER=0 ALIGN=CENTER WIDTH=100%>\n";
  print "   <TR>\n";
  print "    <TD ALIGN=LEFT VALIGN=BOTTOM>\n";
  print "     <FONT SIZE=7>\n";
  print "      <B>\n       <U>\n";
  if (defined($msg{$msgid}{$lang})) {
    for $text (@{$title{$msgid}{$lang}}) {
      eval "\$text = \"$text\"";
      print "       $text\n";
    }
  } else {
    for $text (@{$title{"default"}{$lang}}) {
      eval "\$text = \"$text\"";
      print "       $text\n";
    }
  }
  print "       </U>\n      </B>\n";
  print "     </FONT>\n";
  print "    </TD>\n";
  print "    <TD ROWSPAN=2 ALIGN=RIGHT>\n";
  if (defined($logo{$msgid}{"url"})) {
    print "     <A HREF=\"$logo{$msgid}{\"href\"}\"><IMG\n";
  } else {
    print "     <A HREF=\"$logo{\"default\"}{\"href\"}\"><IMG\n";
  }
  if (defined($logo{$msgid}{"url"})) {
    print "     SRC=\"$logo{$msgid}{\"url\"}\" BORDER=0 ALIGN=TOP></A>\n";
  } else {
    print "     SRC=\"$logo{\"default\"}{\"url\"}\" BORDER=0 ALIGN=TOP></A>\n";
  }
  print "    </TD>\n";
  print "   </TR>\n";
  if ($lang eq $defl && defined($msg{"deflang"}{$lang})) {
    print "   <TR><!-- \$msg{\"deflang\"}{$lang} -->\n";
    print "    <TH ALIGN=LEFT VALIGN=TOP>\n";
    print "     <FONT SIZE=-1>\n";
    print "      <B>\n";
    for $text (@{$msg{"deflang"}{$lang}}) {
      eval "\$text = \"$text\"";
      print "       $text\n";
    }
    print "      </B>\n";
    print "     </FONT>\n";
    print "    </TH>\n";
    print "   </TR>\n";
  }
  print "  </TABLE>\n";
}

#
# PRINT THE ENDING HTML TAGS FOR BODY AND HTML:
#
sub terminator() {
  print " </BODY>\n</HTML>\n";
}

#
# PRINT A MESSAGE WITH THE SPECIFIED TYPE (P,H1,H2,..):
#
sub msg($$) {
  my ($type,$msgid) = @_;
  my $text;
  print "  <$type ALIGN=CENTER><!-- \$msg{$msgid}{$lang} -->\n";
  if (defined($msg{$msgid}{$lang})) {
    for $text (@{$msg{$msgid}{$lang}}) {
      eval "\$text = \"$text\"";
      print "   $text\n";
    }
  } else {
    print "   <EM><B>ERROR: missing message \"$msgid\"</B></EM>\n";
  }
  print "  </$type>\n";
}

#
# PRINT A TABLE WITH THE SPECIFIED FORMAT:
#
sub table($$@) {
  my @format = split(/,/,shift);
  my $table  = shift;
  my $cols   = @format;
  my @msgids = @_;
  my $msgid;
  my $text;
  my %type;
  %type->{"L"} = [ "<TH ALIGN=LEFT>", "</TH>" ];
  %type->{"C"} = [ "<TH ALIGN=CENTER>", "</TH>" ];
  %type->{"R"} = [ "<TH ALIGN=RIGHT>", "</TH>" ];
  %type->{"l"} = [ "<TD ALIGN=LEFT>", "</TD>" ];
  %type->{"c"} = [ "<TD ALIGN=CENTER>", "</TD>" ];
  %type->{"r"} = [ "<TD ALIGN=RIGHT>", "</TD>" ];
  print "  <TABLE BORDER=0 ALIGN=CENTER><!-- table(\"$table\") -->\n";
  if (defined($tab{$table})) {
    if (defined($tab{$table}{"caption"}{$lang})) {
      #print "   <CAPTION ALIGN=LEFT>\n";
      print "   <TH ALIGN=LEFT>\n";
      print "    <FONT SIZE=+1>\n";
      for $text (@{$tab{$table}{"caption"}{$lang}}) {
	eval "\$text = \"$text\"";
	print "    $text\n";
      }
      print "    </FONT>\n";
      #print "   </CAPTION>\n";
      print "   </TH>\n";
    }
    for $msgid (@msgids) {
      print "   <TR>\n";
      if (defined($tab{$table}{$msgid}{$lang})) {
	my $i = 0;
	for $text (@{$tab{$table}{$msgid}{$lang}}) {
	  eval "\$text = \"$text\"";
	  print "    $type{$format[$i]}[0]\n";
	  print "     $text\n";
	  print "    $type{$format[$i]}[1]\n";
	  $i++;
	}
      } else {
	print "   $type{$format[0]}[0]\n";
	print "    <EM><B>ERROR: missing table message \"$msgid\"</B></EM>\n";
	print "   $type{$format[0]}[1]\n";
      }
      print "   </TR>\n";
    }
  } else {
    print "   <TR>\n";
    print "    <TH ALIGN=CENTER>\n";
    print "     <EM><B>ERROR: missing message \"$msgid\"</B></EM>\n";
    print "    </TH>\n";
    print "   </TR>\n";
  }
  print "  </TABLE>\n";
}

#
# PRINT A LINK HREF:
#
sub href($) {
  my $href = shift;
  print "<A HREF=\"$href\">$href</A>";
}

#
# REVERSE LOOKUP AND RETURN NAMES:
#
sub gethostnames($) {
  my $address = shift;
  my ($name,$aliases) = gethostbyaddr(inet_aton($address), AF_INET);
  my @names;
  if (defined($name)) {
    push(@names,$name);
    if (defined($aliases) && $aliases) {
      for(split(/\s+/,$aliases)) {
	next unless(/\./);
	push(@names,$_);
      }
    }
  }
  return(@names);
}

#
# SPLIT AN URL INTO PROTOCOL, ADDRESS, PORT AND PATH:
#
sub spliturl($) {
  my $url      = shift;
  my $protocol = "";
  my $address  = "";
  my $port     = "";
  my $path     = "";
  $url =~ /^([^\/:]+):\/\/([^\/:]+)(:\d*)?(.*)/;
  $protocol = $1 if(defined($1));
  $address  = $2 if(defined($2));
  $port     = $3 if(defined($3));
  $path     = $4 if(defined($4));
  return($protocol,$address,$port,$path);
}

#
# SHOW THE CONFIGURED MESSAGE AS HTML:
#
sub showhtml($) {
  my $msgid = shift;
  status("403 Forbidden");
  content("text/html");
  expires(0);
  title($msgid);
  $msgid = "default" unless(defined($msgconf{$msgid}));
  if (defined($msgconf{$msgid})) {
    print "  <!-- showhtml(\"$msgid\") -->\n";
    for (@{$msgconf{$msgid}}) {
      my @config = split(/:/);
      my $type = shift(@config);
      if ($type eq "msg") {
	msg($config[0],$config[1]);
      } elsif ($type eq "tab") {
	table(shift(@config),shift(@config),@config);
      }
    }
  } else {
    print "  <P><EM><B>ERROR: missing msgconf for \"$msgid\"</B></EM></P>\n";
  }
  terminator();
}

#
# SEND OUT AN IMAGE:
#
sub showimage($$$) {
  my ($type,$file,$redirect) = @_;
  content("image/$type");
  expires(300);
  redirect($redirect) if($redirect);
  print "\n";
  open(GIF, "$ENV{\"DOCUMENT_ROOT\"}$file");
  print <GIF>;
  close(GIF)
}

#
# SHOW THE INADDR ALERNATIVES WITH OPTIONAL ATOREDIRECT:
#
sub showinaddr($$$$$) {
  my ($targetgroup,$protocol,$address,$port,$path) = @_;
  my $msgid = $targetgroup;
  my @names = gethostnames($address);
  if($autoinaddr == 2 && @names || $autoinaddr && @names==1) {
    status("301 Moved Permanently");
    redirect("$protocol://$names[0]$port$path");
  } elsif (@names>1) {
    status("300 Multiple Choices");
  } elsif (@names) {
    status("301 Moved Permanently");
  } else {
    status("404 Not Found");
  }
  if ($path =~ /\.(gif|jpg|jpeg|mp3|mpg|mpeg|avi|mov)$/i) {
    showimage("gif",$image,$redirect);
  } elsif (@names) {
    content("text/html");
    expires(0);
    title($msgid);
    $msgid = "in-addr" unless(defined($msgconf{$msgid}));
    if (defined($msgconf{$msgid})) {
      print "  <!-- showinaddr(\"$msgid\") -->\n";
      for (@{$msgconf{$msgid}}) {
	my @config = split(/:/);
	my $type = shift(@config);
	if ($type eq "msg") {
	  msg($config[0],$config[1]);
	} elsif ($type eq "tab") {
	  table(shift(@config),shift(@config),@config);
	} elsif ($type eq "alternatives") {
	  print "  <TABLE BORDER=0 ALIGN=CENTER>\n";
	  for (@names) {
	    print "   <TR>\n    <TH ALIGN=LEFT>\n     <FONT SIZE=+1>";
	    href("$protocol://$_$port$path");
	    print "\n     </FONT>\n    </TH>\n   </TR>\n";
	  }
	  print "  </TABLE>\n\n";
	  if (defined($ENV{"HTTP_REFERER"}) && $ENV{"HTTP_REFERER"} =~ /:\/\/([^\/:]+)/) {
	    $refererhost = $1;
	    $referer = $ENV{"HTTP_REFERER"};
	    msg("H4","referermaster");
	  }
	}
      }
    } else {
      print "  <P><EM><B>ERROR: missing msgconf for \"$msgid\"</B></EM></P>\n";
    }
    terminator();
  } else {
    showhtml("noalternatives");
  }
}

#
# NOW JUST DO IT:
#
msginit();
if ($targetgroup eq "in-addr") {
  showinaddr($targetgroup,$protocol,$address,$port,$path);
} elsif ($url =~ /\.(gif|jpg|jpeg|mp3|mpg|mpeg|avi|mov)$/i) {
  status("403 Forbidden");
  showimage("gif",$image,$redirect);
} else {
  showhtml($clientgroup);
}
exit 0;
