--- loncom/cgi/ping.pl	2008/12/25 01:56:03	1.8
+++ loncom/cgi/ping.pl	2011/10/17 17:23:25	1.9
@@ -1,6 +1,6 @@
 #!/usr/bin/perl
 # ping cgi-script
-# $Id: ping.pl,v 1.8 2008/12/25 01:56:03 raeburn Exp $
+# $Id: ping.pl,v 1.9 2011/10/17 17:23:25 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -38,19 +38,28 @@ print("Content-type: text/plain\n\n");
 &main();
 
 sub main {
-    if (!&LONCAPA::lonauthcgi::check_ipbased_access('ping')) {
-        if (!&LONCAPA::loncgi::check_cookie_and_load_env()) {
-            return;
+    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')) {
+            $allowed = 1;
         }
-
-        if (!&LONCAPA::lonauthcgi::can_view('ping')) {
-            return;
+    }
+    if ($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';
     }
-
-    my $testhost=$ENV{'QUERY_STRING'};
-    $testhost=~s/\W//g;
-
-    print &Apache::lonnet::reply('ping',$testhost)."\n";
     return;
 }