Rewrite redirect_wrapper.

The wrapper had multiple errors in handling the new version of the
squid redirector protocol and was awful to maintain as it did not
fulfill any coding guidelines at all.

diff --git a/config/urlfilter/redirect_wrapper b/config/urlfilter/redirect_wrapper
index 96cc0a094ba997dc387b5eadf4660e8b41286f38..3e8b49eacd945c7f2be81b3e39b0eb3e7051e9a8 100644 (file)
--- a/config/urlfilter/redirect_wrapper
+++ b/config/urlfilter/redirect_wrapper
@@ -21,12 +21,9 @@
 #                                                                             #
 ###############################################################################
 
-use strict;
 use IPC::Open2;
 use IO::Handle;
 
-my $redirectors;
-
 require '/var/ipfire/general-functions.pl';
 
 my %proxysettings=();
@@ -35,15 +32,20 @@ $proxysettings{'ENABLE_CLAMAV'} = 'off';
 $proxysettings{'ENABLE_UPDXLRATOR'} = 'off';
 &General::readhash("${General::swroot}/proxy/settings", \%proxysettings);
 
-# define here your redirectors (use a comma sperated list)
-if ( $proxysettings{'ENABLE_FILTER'} eq 'on' && $proxysettings{'ENABLE_CLAMAV'} eq 'on' && $proxysettings{'ENABLE_UPDXLRATOR'} eq 'on' ){$redirectors = [ '/usr/bin/squidGuard', '/usr/bin/squidclamav', '/usr/sbin/updxlrator' ];}
-elsif ( $proxysettings{'ENABLE_FILTER'} eq 'on' && $proxysettings{'ENABLE_CLAMAV'} eq 'on' && $proxysettings{'ENABLE_UPDXLRATOR'} eq 'off' ){$redirectors = [ '/usr/bin/squidGuard', '/usr/bin/squidclamav' ];}
-elsif ( $proxysettings{'ENABLE_FILTER'} eq 'on' && $proxysettings{'ENABLE_CLAMAV'} eq 'off' && $proxysettings{'ENABLE_UPDXLRATOR'} eq 'on' ){$redirectors = [ '/usr/bin/squidGuard', '/usr/sbin/updxlrator' ];}
-elsif ( $proxysettings{'ENABLE_FILTER'} eq 'on' && $proxysettings{'ENABLE_CLAMAV'} eq 'off' && $proxysettings{'ENABLE_UPDXLRATOR'} eq 'off' ){$redirectors = [ '/usr/bin/squidGuard' ];}
-elsif ( $proxysettings{'ENABLE_FILTER'} eq 'off' && $proxysettings{'ENABLE_CLAMAV'} eq 'on' && $proxysettings{'ENABLE_UPDXLRATOR'} eq 'on' ){$redirectors = [ '/usr/bin/squidclamav', '/usr/sbin/updxlrator' ];}
-elsif ( $proxysettings{'ENABLE_FILTER'} eq 'off' && $proxysettings{'ENABLE_CLAMAV'} eq 'on' && $proxysettings{'ENABLE_UPDXLRATOR'} eq 'off' ){$redirectors = [ '/usr/bin/squidclamav' ];}
-elsif ( $proxysettings{'ENABLE_FILTER'} eq 'off' && $proxysettings{'ENABLE_CLAMAV'} eq 'off' && $proxysettings{'ENABLE_UPDXLRATOR'} eq 'on' ){$redirectors = [ '/usr/sbin/updxlrator' ];}
-else  { $redirectors = [ '/usr/bin/squidGuard', '/usr/sbin/updxlrator' ];}
+# define here your redirectors
+my @redirectors = ();
+
+if ($proxysettings{'ENABLE_FILTER'} eq 'on') {
+       push(@redirectors, "/usr/bin/squidGuard");
+}
+
+if ($proxysettings{'ENABLE_CLAMAV'} eq 'on') {
+       push(@redirectors, "/usr/bin/squidclamav");
+}
+
+if ($proxysettings{'ENABLE_UPDXLRATOR'} eq 'on') {
+       push(@redirectors, "/usr/sbin/updxlrator");
+}
 
 # Attention: keep in mind that the order of your redirectors is important.
 # It doesn't make sense to scan for viruses on pages you restrict access to...
@@ -55,68 +57,89 @@ else  { $redirectors = [ '/usr/bin/squidGuard', '/usr/sbin/updxlrator' ];}
 # init
 $| = 1;
 STDOUT->autoflush(1);
-my $line;
-my $return;
-my $i;
+
 my $debug=0; # enable only for debugging
 
-if ( -e "/var/ipfire/proxy/enable_redirector_debug" ){
-       $debug = 1;
+if (-e "/var/ipfire/proxy/enable_redirector_debug") {
        writetolog("Urlfilter = ".$proxysettings{'ENABLE_FILTER'}." Clamav = ".$proxysettings{'ENABLE_CLAMAV'}." Updxlrator = ".$proxysettings{'ENABLE_UPDXLRATOR'});
-       }
+       $debug = 1;
+}
 
-# open progamms
-my $pidlist = [];
-my $rlist = [];
-my $wlist = [];
+# Open one instance for each redirector in the list and
+# put them into an array with the STDIN and STDOUT file
+# descriptors.
+my @instances = ();
 
-for($i = 0; $i < @$redirectors; $i++) {
-       $pidlist->[$i] = open2($rlist->[$i], $wlist->[$i], $redirectors->[$i]);
-       if ($debug){
-               writetolog("Current redirector is ".$redirectors->[$i]." number ".$i." PID ".$pidlist->[$i]);
-               }
+foreach my $redirector (@redirectors) {
+       my $desc_out = new IO::Handle();
+       my $desc_in  = new IO::Handle();
+
+       my $pid = open2($desc_out, $desc_in, $redirector);
+
+       if ($debug) {
+               &writetolog("Started an instance of $redirector with PID $pid");
        }
 
+       push(@instances, [$redirector, $desc_out, $desc_in]);
+}
+
 # wait for data...
-while($line = <>) {
-       $return = "";
+my $line;
+while ($line = <>) {
+       my $return = "ERR\n";
 
-       for($i = 0; $i < @$redirectors; $i++) {
-               $wlist->[$i]->print($line);
-               $return = $rlist->[$i]->getline;
+       foreach my $instance (@instances) {
+               my $redirector = @$instance[0];
+               my $desc_out   = @$instance[1];
+               my $desc_in    = @$instance[2];
+               my $response;
 
-               if ( $return eq "Processing file and database" ){
+               # Send request to the redirector.
+               $desc_in->print($line);
+
+               # Wait for a response.
+               $response = $desc_out->getline;
+
+               # Catch invalid responses from squidGuard.
+               if ($redirector eq "/usr/bin/squidGuard" && $response eq "Processing file and database") {
                        system("logger -t ipfire 'Emergency - squidGuard not initialised please run squidGuard -C all'");
-                       }
+                       next;
+               }
 
-               if ($debug){
-                       my $dline = $line;my $dreturn = $return;chomp $dline;chomp $dreturn;
-                       if ( $return eq $line or $return eq "\n" or $return eq "" ){
-                               writetolog("Request equals result by ".$redirectors->[$i]." ".$dline);
-                               }
-                       else {
-                               writetolog($redirectors->[$i]." answers ".$dreturn."\n   Querried ".$dline);
-                               }
-                       }
+               # Writing debug output.
+               if ($debug) {
+                       my $len_response = length($response);
+
+                       &writetolog("Queried $redirector for: $line");
+                       &writetolog("  --> Response ($len_response): $response");
+               }
 
-               # break if redirector changes data
-               if($return ne "ERR\n" and $return ne $line ){
-                       if ( $redirectors->[$i] ne "/usr/sbin/updxlrator"){
-                               if ($debug){
-                                       writetolog($redirectors->[$i]." is stopping querry because block was found.");
-                                       }
-                               $i = @$redirectors;
-                               }
+               # If we got a decisive response, we send it back to squid
+               # and stop querying any more redirectors.
+               if ($response =~ /^(OK|BH)/) {
+                       if ($debug) {
+                               &writetolog("  --  Stopped querying redirectors");
                        }
+
+                       $return = $response;
+                       last;
                }
-       print $return;
        }
 
+       # Send response back to squid.
+       if ($debug) {
+               &writetolog("Sending back to squid: $return");
+       }
+       print $return;
+}
+
 exit 0;
 
 sub writetolog {
-       open(DATEI, ">>/var/log/squid/redirector_debug") || die "Unable to acces file /var/log/squid/redirector_debug";
-       my $log = shift;
-       print DATEI $log."\n";
-       close(DATEI);
-       }
+       my $message = shift;
+       chomp($message);
+
+       open(FILE, ">>/var/log/squid/redirector_debug") || die "Unable to acces file /var/log/squid/redirector_debug";
+       print FILE "$message\n";
+       close(FILE);
+}