--- loncom/interface/loncommon.pm	2008/09/04 22:06:27	1.679
+++ loncom/interface/loncommon.pm	2008/09/19 22:50:01	1.679.2.1
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # a pile of common routines
 #
-# $Id: loncommon.pm,v 1.679 2008/09/04 22:06:27 riegler Exp $
+# $Id: loncommon.pm,v 1.679.2.1 2008/09/19 22:50:01 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -3746,6 +3746,60 @@ sub blocking_status {
 }
 
 ###############################################
+
+sub check_ip_acc {
+    my ($acc)=@_;
+    &Apache::lonxml::debug("acc is $acc");
+    if (!defined($acc) || $acc =~ /^\s*$/ || $acc =~/^\s*no\s*$/i) {
+        return 1;
+    }
+    my $allowed=0;
+    my $ip=$env{'request.host'} || $ENV{'REMOTE_ADDR'};
+
+    my $name;
+    foreach my $pattern (split(',',$acc)) {
+        $pattern =~ s/^\s*//;
+        $pattern =~ s/\s*$//;
+        if ($pattern =~ /\*$/) {
+            #35.8.*
+            $pattern=~s/\*//;
+            if ($ip =~ /^\Q$pattern\E/) { $allowed=1; }
+        } elsif ($pattern =~ /(\d+\.\d+\.\d+)\.\[(\d+)-(\d+)\]$/) {
+            #35.8.3.[34-56]
+            my $low=$2;
+            my $high=$3;
+            $pattern=$1;
+            if ($ip =~ /^\Q$pattern\E/) {
+                my $last=(split(/\./,$ip))[3];
+                if ($last <=$high && $last >=$low) { $allowed=1; }
+            }
+        } elsif ($pattern =~ /^\*/) {
+            #*.msu.edu
+            $pattern=~s/\*//;
+            if (!defined($name)) {
+                use Socket;
+                my $netaddr=inet_aton($ip);
+                ($name)=gethostbyaddr($netaddr,AF_INET);
+            }
+            if ($name =~ /\Q$pattern\E$/i) { $allowed=1; }
+        } elsif ($pattern =~ /\d+\.\d+\.\d+\.\d+/) {
+            #127.0.0.1
+            if ($ip =~ /^\Q$pattern\E/) { $allowed=1; }
+        } else {
+            #some.name.com
+            if (!defined($name)) {
+                use Socket;
+                my $netaddr=inet_aton($ip);
+                ($name)=gethostbyaddr($netaddr,AF_INET);
+            }
+            if ($name =~ /\Q$pattern\E$/i) { $allowed=1; }
+        }
+        if ($allowed) { last; }
+    }
+    return $allowed;
+}
+
+###############################################
 
 =pod