loncom/auth/lonauth.pm - view

File: [LON-CAPA] / loncom / auth / lonauth.pm
Revision 1.127: download - view: text, annotated - select for diffs
Sun Sep 29 00:49:24 2013 UTC (10 years, 7 months ago) by raeburn
Branches: MAIN
CVS tags: HEAD

- Bug 6675
- Case where $env{'REMOTE_ADDR'} as reported to server selected to host
  user session, is different from $env{'REMOTE_ADDR'} as reported to
  server which handled original authentication request.
  - Domain configuration for a load balancing server can be set to one of
    the following, if an IP mismatch is detected by /adm/migrateuser
    during credentials checking after redirect via /adm/switchserver
    (i) Session will be hosted on Load Balancer
    (ii) Session will be hosted on offload server
    for each of (a) SSO users from load balancer's domain, (b) non-SSO users
  - Setting to host on load balancer will be ignored if switch server was called
    by an author or co-author switching to server housing the authoring space.

1: # The LearningOnline Network 2: # User Authentication Module 3: # 4: # $Id: lonauth.pm,v 1.127 2013/09/29 00:49:24 raeburn Exp $ 5: # 6: # Copyright Michigan State University Board of Trustees 7: # 8: # This file is part of the LearningOnline Network with CAPA (LON-CAPA). 9: # 10: # LON-CAPA is free software; you can redistribute it and/or modify 11: # it under the terms of the GNU General Public License as published by 12: # the Free Software Foundation; either version 2 of the License, or 13: # (at your option) any later version. 14: # 15: # LON-CAPA is distributed in the hope that it will be useful, 16: # but WITHOUT ANY WARRANTY; without even the implied warranty of 17: # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18: # GNU General Public License for more details. 19: # 20: # You should have received a copy of the GNU General Public License 21: # along with LON-CAPA; if not, write to the Free Software 22: # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 23: # 24: # /home/httpd/html/adm/gpl.txt 25: # 26: # http://www.lon-capa.org/ 27: # 28: 29: package Apache::lonauth; 30: 31: use strict; 32: use LONCAPA; 33: use Apache::Constants qw(:common); 34: use CGI qw(:standard); 35: use DynaLoader; # for Crypt::DES version 36: use Crypt::DES; 37: use Apache::loncommon(); 38: use Apache::lonnet; 39: use Apache::lonmenu(); 40: use Apache::createaccount; 41: use Fcntl qw(:flock); 42: use Apache::lonlocal; 43: use Apache::File(); 44: use HTML::Entities; 45: 46: # ------------------------------------------------------------ Successful login 47: sub success { 48: my ($r, $username, $domain, $authhost, $lowerurl, $extra_env, 49: $form) = @_; 50: 51: # ------------------------------------------------------------ Get cookie ready 52: my $cookie = 53: &Apache::loncommon::init_user_environment($r, $username, $domain, 54: $authhost, $form, 55: {'extra_env' => $extra_env,}); 56: 57: my $public=($username eq 'public' && $domain eq 'public'); 58: 59: if ($public or $lowerurl eq 'noredirect') { return $cookie; } 60: 61: # -------------------------------------------------------------------- Log this 62: 63: &Apache::lonnet::log($domain,$username,$authhost, 64: "Login $ENV{'REMOTE_ADDR'}"); 65: 66: # ------------------------------------------------- Check for critical messages 67: 68: my @what=&Apache::lonnet::dump('critical',$domain,$username); 69: if ($what[0]) { 70: if (($what[0] ne 'con_lost') && ($what[0]!~/^error\:/)) { 71: $lowerurl='/adm/email?critical=display'; 72: } 73: } 74: 75: # ------------------------------------------------------------ Get cookie ready 76: $cookie="lonID=$cookie; path=/"; 77: # -------------------------------------------------------- Menu script and info 78: my $destination = $lowerurl; 79: 80: if (defined($form->{role})) { 81: my $envkey = 'user.role.'.$form->{role}; 82: my $now=time; 83: my $then=$env{'user.login.time'}; 84: my $refresh=$env{'user.refresh.time'}; 85: my $update=$env{'user.update.time'}; 86: if (!$update) { 87: $update = $then; 88: } 89: if (exists($env{$envkey})) { 90: my ($role,$where,$trolecode,$tstart,$tend,$tremark,$tstatus); 91: &Apache::lonnet::role_status($envkey,$update,$refresh,$now,\$role,\$where, 92: \$trolecode,\$tstatus,\$tstart,\$tend); 93: if ($tstatus eq 'is') { 94: $destination .= ($destination =~ /\?/) ? '&' : '?'; 95: my $newrole = &HTML::Entities::encode($form->{role},'"<>&'); 96: $destination .= 'selectrole=1&'.$newrole.'=1'; 97: } 98: } 99: } 100: if (defined($form->{symb})) { 101: my $destsymb = $form->{symb}; 102: $destination .= ($destination =~ /\?/) ? '&' : '?'; 103: if ($destsymb =~ /___/) { 104: # FIXME Need to deal with encrypted symbs and urls as needed. 105: my ($map,$resid,$desturl)=split(/___/,$destsymb); 106: unless ($desturl=~/^(adm|editupload|public)/) { 107: $desturl = &Apache::lonnet::clutter($desturl); 108: } 109: $desturl = &HTML::Entities::encode($desturl,'"<>&'); 110: $destsymb = &HTML::Entities::encode($destsymb,'"<>&'); 111: $destination .= '&destinationurl='.$desturl. 112: '&destsymb='.$destsymb; 113: } else { 114: $destsymb = &HTML::Entities::encode($destsymb,'"<>&'); 115: $destination .= '&destinationurl='.$destsymb; 116: } 117: } 118: if ($destination =~ m{^/adm/roles}) { 119: $destination .= ($destination =~ /\?/) ? '&' : '?'; 120: $destination .= 'source=login'; 121: } 122: 123: my $windowinfo = Apache::lonhtmlcommon::scripttag('self.name="loncapaclient";'); 124: my $header = '<meta HTTP-EQUIV="Refresh" CONTENT="0; url='.$destination.'" />'; 125: my $brcrum = [{'href' => '', 126: 'text' => 'Successful Login'},]; 127: my $start_page=&Apache::loncommon::start_page('Successful Login', 128: $header, 129: {'bread_crumbs' => $brcrum,}); 130: my $end_page =&Apache::loncommon::end_page(); 131: 132: my $continuelink='<a href="'.$destination.'">'.&mt('Continue').'</a>'; 133: # ------------------------------------------------- Output for successful login 134: 135: &Apache::loncommon::content_type($r,'text/html'); 136: $r->header_out('Set-cookie' => $cookie); 137: $r->send_http_header; 138: 139: my %lt=&Apache::lonlocal::texthash( 140: 'wel' => 'Welcome', 141: 'pro' => 'Login problems?', 142: ); 143: my $loginhelp = &loginhelpdisplay($domain); 144: if ($loginhelp) { 145: $loginhelp = '<p><a href="'.$loginhelp.'">'.$lt{'pro'}.'</a></p>'; 146: } 147: 148: my $welcome = &mt('Welcome to the Learning[_1]Online[_2] Network with CAPA. Please wait while your session is being set up.','<i>','</i>'); 149: $r->print(<<ENDSUCCESS); 150: $start_page 151: $windowinfo 152: <h1>$lt{'wel'}</h1> 153: $welcome 154: $loginhelp 155: $continuelink 156: $end_page 157: ENDSUCCESS 158: } 159: 160: # --------------------------------------------------------------- Failed login! 161: 162: sub failed { 163: my ($r,$message,$form) = @_; 164: my $start_page = &Apache::loncommon::start_page('Unsuccessful Login',undef); 165: my $retry = '/adm/login?username='.$form->{'uname'}. 166: '&domain='.$form->{'udom'}; 167: if (exists($form->{role})) { 168: $retry .= '&role='.$form->{role}; 169: } 170: if (exists($form->{symb})) { 171: $retry .= '&symb='.$form->{symb}; 172: } 173: my $end_page = &Apache::loncommon::end_page(); 174: &Apache::loncommon::content_type($r,'text/html'); 175: $r->send_http_header; 176: my $loginhelp = &loginhelpdisplay($form->{'udom'}); 177: if ($loginhelp) { 178: $loginhelp = '<p><a href="'.$loginhelp.'">'.&mt('Login problems?').'</a></p>'; 179: } 180: 181: $r->print( 182: $start_page 183: .'<h1>'.&mt('Sorry ...').'</h1>' 184: .'<p class="LC_warning">'.&mt($message).'</p>' 185: .'<p>'.&mt('Please [_1]log in again[_2].','<a href="'.$retry.'">','</a>') 186: .'</p>' 187: .$loginhelp 188: .$end_page 189: ); 190: } 191: 192: # ------------------------------------------------------------------ Rerouting! 193: 194: sub reroute { 195: my ($r) = @_; 196: &Apache::loncommon::content_type($r,'text/html'); 197: $r->send_http_header; 198: my $msg='<b>'.&mt('Sorry ...').'</b><br />' 199: .&mt('Please [_1]log in again[_2].'); 200: &Apache::loncommon::simple_error_page($r,'Rerouting',$msg,{'no_auto_mt_msg' => 1}); 201: } 202: 203: # ---------------------------------------------------------------- Main handler 204: 205: sub handler { 206: my $r = shift; 207: my $londocroot = $r->dir_config('lonDocRoot'); 208: my $form; 209: # Are we re-routing? 210: if (-e "$londocroot/lon-status/reroute.txt") { 211: &reroute($r); 212: return OK; 213: } 214: 215: &Apache::lonlocal::get_language_handle($r); 216: 217: # -------------------------------- Prevent users from attempting to login twice 218: my $handle = &Apache::lonnet::check_for_valid_session($r); 219: if ($handle ne '') { 220: my $lonidsdir=$r->dir_config('lonIDsDir'); 221: if ($handle=~/^publicuser\_/) { 222: # For "public user" - remove it, we apparently really want to login 223: unlink($r->dir_config('lonIDsDir')."/$handle.id"); 224: } else { 225: # Indeed, a valid token is found 226: &Apache::lonnet::transfer_profile_to_env($lonidsdir,$handle); 227: &Apache::loncommon::content_type($r,'text/html'); 228: $r->send_http_header; 229: my $start_page = 230: &Apache::loncommon::start_page('Already logged in'); 231: my $end_page = 232: &Apache::loncommon::end_page(); 233: my $dest = '/adm/roles'; 234: if ($env{'form.firsturl'} ne '') { 235: $dest = $env{'form.firsturl'}; 236: } 237: $r->print( 238: $start_page 239: .'<p class="LC_warning">'.&mt('You are already logged in!').'</p>' 240: .'<p>'.&mt('Please either [_1]continue the current session[_2] or [_3]log out[_4].' 241: ,'<a href="'.$dest.'">','</a>','<a href="/adm/logout">','</a>') 242: .'</p>' 243: .$end_page 244: ); 245: return OK; 246: } 247: } 248: 249: # ---------------------------------------------------- No valid token, continue 250: 251: 252: my $buffer; 253: if ($r->header_in('Content-length') > 0) { 254: $r->read($buffer,$r->header_in('Content-length'),0); 255: } 256: my %form; 257: foreach my $pair (split(/&/,$buffer)) { 258: my ($name,$value) = split(/=/,$pair); 259: $value =~ tr/+/ /; 260: $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C",hex($1))/eg; 261: $form{$name}=$value; 262: } 263: 264: if ((!$form{'uname'}) || (!$form{'upass0'}) || (!$form{'udom'})) { 265: &failed($r,'Username, password and domain need to be specified.', 266: \%form); 267: return OK; 268: } 269: 270: # split user logging in and "su"-user 271: 272: ($form{'uname'},$form{'suname'})=split(/\:/,$form{'uname'}); 273: $form{'uname'} = &LONCAPA::clean_username($form{'uname'}); 274: $form{'suname'}= &LONCAPA::clean_username($form{'suname'}); 275: $form{'udom'} = &LONCAPA::clean_domain( $form{'udom'}); 276: 277: my $role = $r->dir_config('lonRole'); 278: my $domain = $r->dir_config('lonDefDomain'); 279: my $prodir = $r->dir_config('lonUsersDir'); 280: my $contact_name = &mt('LON-CAPA helpdesk'); 281: 282: # ---------------------------------------- Get the information from login token 283: 284: my $tmpinfo=Apache::lonnet::reply('tmpget:'.$form{'logtoken'}, 285: $form{'serverid'}); 286: 287: my %sessiondata; 288: if ($form{'iptoken'}) { 289: %sessiondata = &Apache::lonnet::tmpget($form{'iptoken'}); 290: my $delete = &Apache::lonnet::tmpdel($form{'token'}); 291: } 292: 293: if (($tmpinfo=~/^error/) || ($tmpinfo eq 'con_lost') || 294: ($tmpinfo eq 'no_such_host')) { 295: &failed($r,'Information needed to verify your login information is missing, inaccessible or expired.',\%form); 296: return OK; 297: } else { 298: my $reply = &Apache::lonnet::reply('tmpdel:'.$form{'logtoken'}, 299: $form{'serverid'}); 300: if ( $reply ne 'ok' ) { 301: &failed($r,'Session could not be opened.',\%form); 302: &Apache::lonnet::logthis("ERROR got a reply of $reply when trying to contact ". $form{'serverid'}." to get login token"); 303: return OK; 304: } 305: } 306: 307: if (!&Apache::lonnet::domain($form{'udom'})) { 308: &failed($r,'The domain you provided is not a valid LON-CAPA domain.',\%form); 309: return OK; 310: } 311: 312: my ($key,$firsturl,$rolestr,$symbstr)=split(/&/,$tmpinfo); 313: if ($rolestr) { 314: $rolestr = &unescape($rolestr); 315: } 316: if ($symbstr) { 317: $symbstr= &unescape($symbstr); 318: } 319: if ($rolestr =~ /^role=/) { 320: (undef,$form{'role'}) = split('=',$rolestr); 321: } 322: if ($symbstr =~ /^symb=/) { 323: (undef,$form{'symb'}) = split('=',$symbstr); 324: } 325: 326: my $keybin=pack("H16",$key); 327: 328: my $cipher; 329: if ($Crypt::DES::VERSION>=2.03) { 330: $cipher=new Crypt::DES $keybin; 331: } 332: else { 333: $cipher=new DES $keybin; 334: } 335: my $upass=''; 336: for (my $i=0;$i<=2;$i++) { 337: my $chunk= 338: $cipher->decrypt(unpack("a8",pack("H16",substr($form{'upass'.$i},0,16)))); 339: 340: $chunk.= 341: $cipher->decrypt(unpack("a8",pack("H16",substr($form{'upass'.$i},16,16)))); 342: 343: $chunk=substr($chunk,1,ord(substr($chunk,0,1))); 344: $upass.=$chunk; 345: } 346: 347: # ---------------------------------------------------------------- Authenticate 348: 349: my %domconfig = &Apache::lonnet::get_dom('configuration',['usercreation'],$form{'udom'}); 350: my ($cancreate,$statustocreate) = 351: &Apache::createaccount::get_creation_controls($form{'udom'},$domconfig{'usercreation'}); 352: my $defaultauth; 353: if (ref($cancreate) eq 'ARRAY') { 354: if (grep(/^login$/,@{$cancreate})) { 355: $defaultauth = 1; 356: } 357: } 358: my $clientcancheckhost = 1; 359: my $authhost=Apache::lonnet::authenticate($form{'uname'},$upass, 360: $form{'udom'},$defaultauth, 361: $clientcancheckhost); 362: 363: # --------------------------------------------------------------------- Failed? 364: 365: if ($authhost eq 'no_host') { 366: &failed($r,'Username and/or password could not be authenticated.', 367: \%form); 368: return OK; 369: } elsif ($authhost eq 'no_account_on_host') { 370: if ($defaultauth) { 371: my $domdesc = &Apache::lonnet::domain($form{'udom'},'description'); 372: unless (&check_can_host($r,\%form,'no_account_on_host',$domdesc)) { 373: return OK; 374: } 375: my $start_page = 376: &Apache::loncommon::start_page('Create a user account in LON-CAPA'); 377: my $lonhost = $r->dir_config('lonHostID'); 378: my $origmail = $Apache::lonnet::perlvar{'lonSupportEMail'}; 379: my $contacts = 380: &Apache::loncommon::build_recipient_list(undef,'helpdeskmail', 381: $form{'udom'},$origmail); 382: my ($contact_email) = split(',',$contacts); 383: my $output = 384: &Apache::createaccount::username_check($form{'uname'},$form{'udom'}, 385: $domdesc,'',$lonhost, 386: $contact_email,$contact_name, 387: undef,$statustocreate); 388: &Apache::loncommon::content_type($r,'text/html'); 389: $r->send_http_header; 390: &Apache::createaccount::print_header($r,$start_page); 391: $r->print('<h3>'.&mt('Account creation').'</h3>'. 392: &mt('Although your username and password were authenticated, you do not currently have a LON-CAPA account at this institution.').'<br />'. 393: $output.&Apache::loncommon::end_page()); 394: return OK; 395: } else { 396: &failed($r,'Although your username and password were authenticated, you do not currently have a LON-CAPA account in this domain, and you are not permitted to create one.',\%form); 397: return OK; 398: } 399: } 400: 401: if (($firsturl eq '') || 402: ($firsturl=~/^\/adm\/(logout|remote)/)) { 403: $firsturl='/adm/roles'; 404: } 405: 406: my $hosthere; 407: if ($form{'iptoken'}) { 408: if (($sessiondata{'domain'} eq $form{'udom'}) && 409: ($sessiondata{'username'} eq $form{'uname'})) { 410: $hosthere = 1; 411: } 412: } 413: 414: # --------------------------------- Are we attempting to login as somebody else? 415: if ($form{'suname'}) { 416: # ------------ see if the original user has enough privileges to pull this stunt 417: if (&Apache::lonnet::privileged($form{'uname'},$form{'udom'})) { 418: # ---------------------------------------------------- see if the su-user exists 419: unless (&Apache::lonnet::homeserver($form{'suname'},$form{'udom'}) 420: eq 'no_host') { 421: &Apache::lonnet::logthis(&Apache::lonnet::homeserver($form{'suname'},$form{'udom'})); 422: # ------------------------------ see if the su-user is not too highly privileged 423: unless (&Apache::lonnet::privileged($form{'suname'},$form{'udom'})) { 424: # -------------------------------------------------------- actually switch users 425: &Apache::lonnet::logperm('User '.$form{'uname'}.' at '.$form{'udom'}. 426: ' logging in as '.$form{'suname'}); 427: $form{'uname'}=$form{'suname'}; 428: } else { 429: &Apache::lonnet::logthis('Attempted switch user to privileged user'); 430: } 431: } 432: } else { 433: &Apache::lonnet::logthis('Non-privileged user attempting switch user'); 434: } 435: } 436: 437: my ($is_balancer,$otherserver); 438: 439: unless ($hosthere) { 440: ($is_balancer,$otherserver) = 441: &Apache::lonnet::check_loadbalancing($form{'uname'},$form{'udom'}); 442: } 443: 444: if ($is_balancer) { 445: if (!$otherserver) { 446: ($otherserver) = &Apache::lonnet::choose_server($form{'udom'}); 447: } 448: if ($otherserver) { 449: &success($r,$form{'uname'},$form{'udom'},$authhost,'noredirect',undef, 450: \%form); 451: $r->internal_redirect('/adm/switchserver?otherserver='.$otherserver.'&origurl='.$firsturl); 452: } else { 453: $r->print(&noswitch()); 454: } 455: return OK; 456: } else { 457: if (!&check_can_host($r,\%form,$authhost)) { 458: my ($otherserver) = &Apache::lonnet::choose_server($form{'udom'}); 459: if ($otherserver) { 460: &success($r,$form{'uname'},$form{'udom'},$authhost,'noredirect',undef, 461: \%form); 462: $r->internal_redirect('/adm/switchserver?otherserver='.$otherserver.'&origurl='.$firsturl); 463: } else { 464: $r->print(&noswitch()); 465: } 466: return OK; 467: } 468: 469: # ------------------------------------------------------- Do the load balancing 470: 471: # ---------------------------------------------------------- Determine own load 472: my $loadlim = $r->dir_config('lonLoadLim'); 473: my $loadavg; 474: { 475: my $loadfile=Apache::File->new('/proc/loadavg'); 476: $loadavg=<$loadfile>; 477: } 478: $loadavg =~ s/\s.*//g; 479: my $loadpercent=sprintf("%.1f",100*$loadavg/$loadlim); 480: my $userloadpercent=&Apache::lonnet::userload(); 481: 482: # ---------------------------------------------------------- Are we overloaded? 483: if ((($userloadpercent>100.0)||($loadpercent>100.0))) { 484: my $unloaded=Apache::lonnet::spareserver($loadpercent,$userloadpercent,1,$form{'udom'}); 485: if (!$unloaded) { 486: ($unloaded) = &Apache::lonnet::choose_server($form{'udom'}); 487: } 488: if ($unloaded) { 489: &success($r,$form{'uname'},$form{'udom'},$authhost,'noredirect', 490: undef,\%form); 491: $r->internal_redirect('/adm/switchserver?otherserver='.$unloaded.'&origurl='.$firsturl); 492: return OK; 493: } 494: } 495: &success($r,$form{'uname'},$form{'udom'},$authhost,$firsturl,undef, 496: \%form); 497: return OK; 498: } 499: } 500: 501: sub check_can_host { 502: my ($r,$form,$authhost,$domdesc) = @_; 503: return unless (ref($form) eq 'HASH'); 504: my $canhost = 1; 505: my $lonhost = $r->dir_config('lonHostID'); 506: my $udom = $form->{'udom'}; 507: my @intdoms; 508: my $internet_names = &Apache::lonnet::get_internet_names($lonhost); 509: if (ref($internet_names) eq 'ARRAY') { 510: @intdoms = @{$internet_names}; 511: } 512: my $uprimary_id = &Apache::lonnet::domain($udom,'primary'); 513: my $uint_dom = &Apache::lonnet::internet_dom($uprimary_id); 514: unless ($uint_dom ne '' && grep(/^\Q$uint_dom\E$/,@intdoms)) { 515: my $machine_dom = &Apache::lonnet::host_domain($lonhost); 516: my $hostname = &Apache::lonnet::hostname($lonhost); 517: my $serverhomeID = &Apache::lonnet::get_server_homeID($hostname); 518: my $serverhomedom = &Apache::lonnet::host_domain($serverhomeID); 519: my %defdomdefaults = &Apache::lonnet::get_domain_defaults($serverhomedom); 520: my %udomdefaults = &Apache::lonnet::get_domain_defaults($udom); 521: my $loncaparev; 522: if ($authhost eq 'no_account_on_host') { 523: $loncaparev = &Apache::lonnet::get_server_loncaparev($machine_dom); 524: } else { 525: $loncaparev = &Apache::lonnet::get_server_loncaparev($machine_dom,$lonhost); 526: } 527: $canhost = &Apache::lonnet::can_host_session($udom,$lonhost,$loncaparev, 528: $udomdefaults{'remotesessions'}, 529: $defdomdefaults{'hostedsessions'}); 530: } 531: unless ($canhost) { 532: if ($authhost eq 'no_account_on_host') { 533: my $checkloginvia = 1; 534: my ($login_host,$hostname) = 535: &Apache::lonnet::choose_server($udom,$checkloginvia); 536: &Apache::loncommon::content_type($r,'text/html'); 537: $r->send_http_header; 538: if ($login_host ne '') { 539: my $protocol = $Apache::lonnet::protocol{$login_host}; 540: $protocol = 'http' if ($protocol ne 'https'); 541: my $newurl = $protocol.'://'.$hostname.'/adm/createaccount'; 542: $r->print(&Apache::loncommon::start_page('Create a user account in LON-CAPA'). 543: '<h3>'.&mt('Account creation').'</h3>'. 544: &mt('You do not currently have a LON-CAPA account at this institution.').'<br />'. 545: '<p>'.&mt('You will be able to create one by logging into a LON-CAPA server within the [_1] domain.',$domdesc).'</p>'. 546: '<p>'.&mt('[_1]Log in[_2]','<a href="'.$newurl.'">','</a>'). 547: &Apache::loncommon::end_page()); 548: } else { 549: $r->print(&Apache::loncommon::start_page('Access to LON-CAPA unavailable'). 550: '<h3>'.&mt('Account creation unavailable').'</h3>'. 551: &mt('You do not currently have a LON-CAPA account at this institution.').'<br />'. 552: '<p>'.&mt('Currently a LON-CAPA server is not available within the [_1] domain for you to log-in to, to create an account.',$domdesc).'</p>'. 553: &Apache::loncommon::end_page()); 554: } 555: } else { 556: &success($r,$form->{'uname'},$udom,$authhost,'noredirect',undef, 557: $form); 558: my ($otherserver) = &Apache::lonnet::choose_server($udom); 559: $r->internal_redirect('/adm/switchserver?otherserver='.$otherserver); 560: } 561: } 562: return $canhost; 563: } 564: 565: sub noswitch { 566: my $result = &Apache::loncommon::start_page('Access to LON-CAPA unavailable'). 567: '<h3>'.&mt('Session unavailable').'</h3>'. 568: &mt('This LON-CAPA server is unable to host your session.').'<br />'. 569: '<p>'.&mt('Currently no other LON-CAPA server is available to host your session either.').'</p>'. 570: &Apache::loncommon::end_page(); 571: return $result; 572: } 573: 574: sub loginhelpdisplay { 575: my ($authdomain) = @_; 576: my $login_help = 1; 577: my $lang = &Apache::lonlocal::current_language(); 578: if ($login_help) { 579: my $dom = $authdomain; 580: if ($dom eq '') { 581: $dom = &Apache::lonnet::default_login_domain(); 582: } 583: my %domconfhash = &Apache::loncommon::get_domainconf($dom); 584: my $loginhelp_url; 585: if ($lang) { 586: $loginhelp_url = $domconfhash{$dom.'.login.helpurl_'.$lang}; 587: if ($loginhelp_url ne '') { 588: return $loginhelp_url; 589: } 590: } 591: $loginhelp_url = $domconfhash{$dom.'.login.helpurl_nolang'}; 592: if ($loginhelp_url ne '') { 593: return $loginhelp_url; 594: } else { 595: return '/adm/loginproblems.html'; 596: } 597: } 598: return; 599: } 600: 601: 1; 602: __END__ 603: 604: