--- loncom/lonnet/perl/lonnet.pm	2010/07/06 18:36:56	1.1072
+++ loncom/lonnet/perl/lonnet.pm	2010/07/17 20:02:13	1.1073
@@ -1,7 +1,7 @@
 # The LearningOnline Network
 # TCP networking package
 #
-# $Id: lonnet.pm,v 1.1072 2010/07/06 18:36:56 www Exp $
+# $Id: lonnet.pm,v 1.1073 2010/07/17 20:02:13 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -76,7 +76,7 @@ use HTTP::Date;
 use Image::Magick;
 
 use vars qw(%perlvar %spareid %pr %prp $memcache %packagetab $tmpdir
-            $_64bit %env %protocol);
+            $_64bit %env %protocol %loncaparevs);
 
 my (%badServerCache, $memcache, %courselogs, %accesshash, %domainrolehash,
     %userrolehash, $processmarker, $dumpcount, %coursedombuf,
@@ -196,7 +196,7 @@ sub get_server_timezone {
 }
 
 sub get_server_loncaparev {
-    my ($dom,$lonhost) = @_;
+    my ($dom,$lonhost,$ignore_cache,$caller) = @_;
     if (defined($lonhost)) {
         if (!defined(&hostname($lonhost))) {
             undef($lonhost);
@@ -211,14 +211,45 @@ sub get_server_loncaparev {
         }
     }
     if (defined($lonhost)) {
-        my $cachetime = 24*3600;
-        my ($loncaparev,$cached)=&is_cached_new('serverloncaparev',$lonhost);
-        if (defined($cached)) {
-            return $loncaparev;
-        } else {
-            my $loncaparev = &reply('serverloncaparev',$lonhost);
-            return &do_cache_new('serverloncaparev',$lonhost,$loncaparev,$cachetime);
+        my $cachetime = 12*3600;
+        if (!$ignore_cache) {
+            my ($loncaparev,$cached)=&is_cached_new('serverloncaparev',$lonhost);
+            if (defined($cached)) {
+                return $loncaparev;
+            }
+        }
+        my ($answer,$loncaparev);
+        my @ids=&current_machine_ids();
+        if (grep(/^\Q$lonhost\E$/,@ids)) {
+            $answer = $perlvar{'lonVersion'};
+            if ($answer =~ /^[\'\"]?([\d.\-]+)[\'\"]?$/) {
+                $loncaparev = $1;
+            }
+        } else {
+            $answer = &reply('serverloncaparev',$lonhost);
+            if (($answer eq 'unknown_cmd') || ($answer eq 'con_lost')) {
+                if ($caller eq 'loncron') {
+                    my $ua=new LWP::UserAgent;
+                    $ua->timeout(20);
+                    my $protocol = $protocol{$lonhost};
+                    $protocol = 'http' if ($protocol ne 'https');
+                    my $url = $protocol.'://'.&hostname($lonhost).'/adm/about.html';
+                    my $request=new HTTP::Request('GET',$url);
+                    my $response=$ua->request($request);
+                    unless ($response->is_error()) {
+                        my $content = $response->content;
+                        if ($content =~ /<p>VERSION\:\s*([\d.\-]+)<\/p>/) {
+                            $loncaparev = $1;
+                        }
+                    }
+                } else {
+                    $loncaparev = $loncaparevs{$lonhost};
+                }
+            } elsif ($answer =~ /^[\'\"]?([\d.\-]+)[\'\"]?$/) {
+                $loncaparev = $1;
+            }
         }
+        return &do_cache_new('serverloncaparev',$lonhost,$loncaparev,$cachetime);
     }
 }
 
@@ -811,7 +842,7 @@ sub queryauthenticate {
 # --------- Try to authenticate user from domain's lib servers (first this one)
 
 sub authenticate {
-    my ($uname,$upass,$udom,$checkdefauth)=@_;
+    my ($uname,$upass,$udom,$checkdefauth,$clientcancheckhost)=@_;
     $upass=&escape($upass);
     $uname= &LONCAPA::clean_username($uname);
     my $uhome=&homeserver($uname,$udom,1);
@@ -834,7 +865,7 @@ sub authenticate {
 	    return 'no_host';
         }
     }
-    my $answer=reply("encrypt:auth:$udom:$uname:$upass:$checkdefauth",$uhome);
+    my $answer=reply("encrypt:auth:$udom:$uname:$upass:$checkdefauth:$clientcancheckhost",$uhome);
     if ($answer eq 'authorized') {
         if ($newhome) {
             &logthis("User $uname at $udom authorized by $uhome, but needs account");
@@ -852,6 +883,63 @@ sub authenticate {
     return 'no_host';
 }
 
+sub can_host_session {
+    my ($udom,$machinedom,$remoterev,$remotesessions,$hostedsessions) = @_;
+    my $canhost = 1;
+    if (ref($remotesessions) eq 'HASH') {
+        if (ref($remotesessions->{'excludedomain'}) eq 'ARRAY') {
+            if (grep(/^\Q$machinedom\E$/,@{$remotesessions->{'excludedomain'}})) {
+                $canhost = 0;
+            } else {
+                $canhost = 1;
+            }
+        }
+        if (ref($remotesessions->{'includedomain'}) eq 'ARRAY') {
+            if (grep(/^\Q$machinedom\E$/,@{$remotesessions->{'includedomain'}})) {
+                $canhost = 1;
+            } else {
+                $canhost = 0;
+            }
+        }
+        if ($canhost) {
+            if ($remotesessions->{'version'} ne '') {
+                my ($reqmajor,$reqminor) = ($remotesessions->{'version'} =~ /^(\d+)\.(\d+)$/);
+                if ($reqmajor ne '' && $reqminor ne '') {
+                    if ($remoterev =~ /^\'?(\d+)\.(\d+)/) {
+                        my $major = $1;
+                        my $minor = $2;
+                        if (($major < $reqmajor ) ||
+                            (($major == $reqmajor) && ($minor < $reqminor))) {
+                            $canhost = 0;
+                        }
+                    } else {
+                        $canhost = 0;
+                    }
+                }
+            }
+        }
+    }
+    if ($canhost) {
+        if (ref($hostedsessions) eq 'HASH') {
+            if (ref($hostedsessions->{'excludedomain'}) eq 'ARRAY') {
+                if (grep(/^\Q$udom\E$/,@{$hostedsessions->{'excludedomain'}})) {
+                    $canhost = 0;
+                } else {
+                    $canhost = 1;
+                }
+            }
+            if (ref($hostedsessions->{'includedomain'}) eq 'ARRAY') {
+                if (grep(/^\Q$udom\E$/,@{$hostedsessions->{'includedomain'}})) {
+                    $canhost = 1;
+                } else {
+                    $canhost = 0;
+                }
+            }
+        }
+    }
+    return $canhost;
+}
+
 # ---------------------- Find the homebase for a user from domain's lib servers
 
 my %homecache;
@@ -1328,7 +1416,7 @@ sub get_domain_defaults {
     my %domconfig =
          &Apache::lonnet::get_dom('configuration',['defaults','quotas',
                                   'requestcourses','inststatus',
-                                  'coursedefaults'],$domain);
+                                  'coursedefaults','usersessions'],$domain);
     if (ref($domconfig{'defaults'}) eq 'HASH') {
         $domdefaults{'lang_def'} = $domconfig{'defaults'}{'lang_def'}; 
         $domdefaults{'auth_def'} = $domconfig{'defaults'}{'auth_def'};
@@ -1368,6 +1456,14 @@ sub get_domain_defaults {
             $domdefaults{$item} = $domconfig{'coursedefaults'}{$item};
         }
     }
+    if (ref($domconfig{'usersessions'}) eq 'HASH') {
+        if (ref($domconfig{'usersessions'}{'remote'}) eq 'HASH') {
+            $domdefaults{'remotesessions'} = $domconfig{'usersessions'}{'remote'};
+        }
+        if (ref($domconfig{'usersessions'}{'hosted'}) eq 'HASH') {
+            $domdefaults{'hostedsessions'} = $domconfig{'usersessions'}{'hosted'};
+        }
+    }
     &Apache::lonnet::do_cache_new('domdefaults',$domain,\%domdefaults,
                                   $cachetime);
     return %domdefaults;
@@ -10003,6 +10099,24 @@ BEGIN {
     close($config);
 }
 
+# ---------------------------------------------------------- Read loncaparev table
+{
+    if (-e "$perlvar{'lonTabDir'}/loncaparevs.tab") {
+        if (open(my $config,"<$perlvar{'lonTabDir'}/loncaparevs.tab")) {
+            while (my $configline=<$config>) {
+                chomp($configline);
+                my ($hostid,$loncaparev)=split(/:/,$configline);
+                $loncaparevs{$hostid}=$loncaparev;
+            }
+            close($config);
+        }
+    }
+}
+
+sub all_loncaparevs {
+    return qw(1.1 1.2 1.3 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 2.10);
+}
+
 # ------------- set up temporary directory
 {
     $tmpdir = $perlvar{'lonDaemons'}.'/tmp/';
@@ -10233,9 +10347,14 @@ authentication scheme
 
 =item *
 X<authenticate()>
-B<authenticate($uname,$upass,$udom)>: try to
+B<authenticate($uname,$upass,$udom,$checkdefauth,$clientcancheckhost)>: try to
 authenticate user from domain's lib servers (first use the current
 one). C<$upass> should be the users password.
+$checkdefauth is optional (value is 1 if a check should be made to
+   authenticate user using default authentication method, and allow
+   account creation if username does not have account in the domain).
+$clientcancheckhost is optional (value is 1 if checking whether the
+   server can host will occur on the client side in lonauth.pm).   
 
 =item *
 X<homeserver()>