--- loncom/cgi/ping.pl	2002/09/09 14:18:56	1.3
+++ loncom/cgi/ping.pl	2011/10/17 17:23:25	1.9
@@ -1,42 +1,65 @@
 #!/usr/bin/perl
-
-# The LearningOnline Network with CAPA
 # ping cgi-script
+# $Id: ping.pl,v 1.9 2011/10/17 17:23:25 raeburn Exp $
+#
+# Copyright Michigan State University Board of Trustees
+#
+# This file is part of the LearningOnline Network with CAPA (LON-CAPA).
+#
+# LON-CAPA 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.
+#
+# LON-CAPA 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.
+#
+# You should have received a copy of the GNU General Public License
+# along with LON-CAPA; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+#
+# /home/httpd/html/adm/gpl.txt
+#
+# http://www.lon-capa.org/
+#
 
-
+use strict;
 $|=1;
 
 use lib '/home/httpd/lib/perl/';
-use LONCAPA::Configuration;
-
-use IO::File;
-use IO::Socket;
-
-# -------------------------------------------------- Non-critical communication
-sub reply {
-    my ($cmd,$server)=@_;
-    my $peerfile="$perlvar{'lonSockDir'}/$server";
-    my $client=IO::Socket::UNIX->new(Peer    =>"$peerfile",
-                                     Type    => SOCK_STREAM,
-                                     Timeout => 10)
-       or return "con_lost";
-    print $client "$cmd\n";
-    my $answer=<$client>;
-    chomp($answer);
-    if (!$answer) { $answer="con_lost"; }
-    return $answer;
+use Apache::lonnet;
+use LONCAPA::loncgi;
+use LONCAPA::lonauthcgi;
+
+print("Content-type: text/plain\n\n");
+
+&main();
+
+sub main {
+    my $remote_ip = $ENV{'REMOTE_ADDR'};
+    my $allowed;
+    my @hosts = &Apache::lonnet::get_hosts_from_ip($remote_ip);
+    if (@hosts > 0) {
+        $allowed = 1;
+    } elsif (&LONCAPA::lonauthcgi::check_ipbased_access('ping',$remote_ip)) {
+        $allowed = 1;
+    } elsif (&LONCAPA::loncgi::check_cookie_and_load_env()) {
+        if (&LONCAPA::lonauthcgi::can_view('ping')) {
+            $allowed = 1;
+        }
+    }
+    if ($allowed) {
+        my $testhost=$ENV{'QUERY_STRING'};
+        $testhost=~s/\W//g;
+        if (&Apache::lonnet::hostname($testhost) ne '') {
+            print &Apache::lonnet::reply('ping',$testhost)."\n";
+        } else {
+            print 'unknown_host';
+        }
+    } else {
+        print 'forbidden';
+    }
+    return;
 }
-
-
-# --------------------- Read loncapa.conf (and by default loncapa_apache.conf).
-my $perlvarref=LONCAPA::Configuration::read_conf('loncapa.conf');
-my %perlvar=%{$perlvarref};
-undef $perlvarref; # remove since sensitive and not needed
-delete $perlvar{'lonReceipt'}; # remove since sensitive and not needed
-delete $perlvar{'lonSqlAccess'}; # remove since sensitive and not needed
-
-$testhost=$ENV{'QUERY_STRING'};
-$testhost=~s/\W//g;
-
-print "Content-type: text/plain\n\n".
-      &reply('ping',$testhost)."\n";