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- Dual SSO and non-SSO login from /adm/login for use with additional SSO
  mechanisms besides Shibboleth.
  - Default is to use /adm/sso for "authentication" URL.
  - Different authentication URL can be set with lonOtherAuthenUrl perlvar.
  - Update documentation for lonshibauth.pm and lonshibacc.pm
  - Wording change for WAF/Proxy domain configuration
  - If Apache config contains lonSSOEmailOK set to 1, default removal
    of @ "internet domain" from username for SSO authenticated users in
    lonshibacc.pm is skipped.
  - &alias_shibboleth() routine in lonnet.pm renamed alias_sso().

    1: # The LearningOnline Network
    2: # Redirect Single Sign On authentication to designated URL: 
    3: # /adm/sso, by default.
    4: #
    5: # $Id: lonshibauth.pm,v 1.13 2021/12/06 03:31:54 raeburn Exp $
    6: #
    7: # Copyright Michigan State University Board of Trustees
    8: #
    9: # This file is part of the LearningOnline Network with CAPA (LON-CAPA).
   10: #
   11: # LON-CAPA is free software; you can redistribute it and/or modify
   12: # it under the terms of the GNU General Public License as published by
   13: # the Free Software Foundation; either version 2 of the License, or
   14: # (at your option) any later version.
   15: #
   16: # LON-CAPA is distributed in the hope that it will be useful,
   17: # but WITHOUT ANY WARRANTY; without even the implied warranty of
   18: # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   19: # GNU General Public License for more details.
   20: #
   21: # You should have received a copy of the GNU General Public License
   22: # along with LON-CAPA; if not, write to the Free Software
   23: # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   24: #
   25: # /home/httpd/html/adm/gpl.txt
   26: #
   27: # http://www.lon-capa.org/
   28: #
   29: 
   30: =head1 NAME
   31: 
   32: Apache::lonshibauth - Redirect Single Sign On authentication
   33: 
   34: =head1 SYNOPSIS
   35: 
   36: Invoked when an Apache config file includes:
   37: PerlAuthenHandler Apache::lonshibauth
   38: 
   39: If server is configured as a Shibboleth SP, the main Apache 
   40: configuration file, e.g., /etc/httpd/conf/httpd.conf
   41: (for RHEL/CentOS/Scentific Linux/Fedora) should contain:
   42: 
   43: LoadModule mod_shib /usr/lib/shibboleth/mod_shib_22.so
   44: 
   45: or equivalent (depending on Apache version) 
   46: before the line to include conf/loncapa_apache.conf
   47: 
   48: If some other Apache module is in use for Single Sign On
   49: authentication e.g., mod_auth_cas or mod_sentinel,
   50: then a separate config file should be created which
   51: includes settings for the authentication module.
   52:  
   53: =head1 INTRODUCTION
   54: 
   55: Redirects a user requiring Single Sign On to a URL on the server  
   56: which is configured to use that service. The default URL is:
   57: /adm/sso. 
   58: 
   59: If this is to be used with a Single Sign On service other Shibboleth
   60: then an Apache config file needs to be loaded which: 
   61: 
   62: (a) loads the corresponding Apache module, and 
   63: (b) sets appropriate values for perl vars in 
   64: an <IfModule mod_***></IfModule> block, and
   65: (c) sets an appropriate value for AuthType in a
   66: <Location /adm/sso><IfModule mod_***>
   67: </IfModule></Location> block, which also contains
   68: 
   69: require valid-user
   70: 
   71: PerlAuthzHandler       Apache::lonshibacc
   72: 
   73: PerlAuthzHandler       Apache::lonacc 
   74: 
   75: In the case of Shibboleth no additional file is needed
   76: because loncapa_apache.conf already contains:
   77: 
   78: <IfModule mod_shib>
   79:     PerlAuthenHandler Apache::lonshibauth
   80:     PerlSetVar lonOtherAuthen yes
   81:     PerlSetVar lonOtherAuthenType Shibboleth
   82: 
   83: </IfModule>
   84: 
   85: and
   86: 
   87: <Location /adm/sso>
   88:   Header set Cache-Control "private,no-store,no-cache,max-age=0"
   89:   <IfModule mod_shib>
   90:     AuthType shibboleth
   91:     ShibUseEnvironment On
   92:     ShibRequestSetting requireSession 1
   93:     ShibRequestSetting redirectToSSL 443
   94:     require valid-user
   95:     PerlAuthzHandler       Apache::lonshibacc
   96:     PerlAuthzHandler       Apache::lonacc
   97:     ErrorDocument     403 /adm/login
   98:     ErrorDocument     500 /adm/errorhandler
   99:   </IfModule>
  100:   <IfModule !mod_shib>
  101:     PerlTypeHandler        Apache::lonnoshib
  102:   </IfModule>
  103: 
  104: </Location>
  105: 
  106: If the service is not Shibboleth, then (optionally) a URL that is 
  107: not /adm/sso can be used as the URL for the service, e.g., /adm/cas
  108: or /adm/sentinel, by setting a lonOtherAuthenUrl perl var
  109: in an Apache config file containing (for example):
  110: 
  111: PerlSetVar lonOtherAuthenUrl /adm/sentinel
  112: 
  113: <IfModule mod_sentinel>
  114:     PerlAuthenHandler Apache::lonshibauth
  115:     PerlSetVar lonOtherAuthen yes
  116:     PerlSetVar lonOtherAuthenType Sentinel
  117: 
  118: </IfModule>
  119: 
  120: <Location /adm/sentinel>
  121:   Header set Cache-Control "private,no-store,no-cache,max-age=0"
  122:   <IfModule mod_sentinel>
  123:     AuthType Sentinel
  124:     require valid-user
  125:     PerlAuthzHandler  Apache::lonshibacc
  126:     PerlAuthzHandler  Apache::lonacc
  127:     ErrorDocument     403 /adm/login
  128:     ErrorDocument     500 /adm/errorhandler
  129:   </IfModule>
  130:   <IfModule !mod_sentinel>
  131:     PerlTypeHandler        Apache::lonnoshib
  132:   </IfModule>
  133: 
  134: </Location>
  135: 
  136: In the example above for Sentinel SSO, it would also be possible to 
  137: use /adm/sso instead of /adm/sentinel, in which case (i) there would be 
  138: no need to define lonOtherAuthenUrl, (ii) there would be <Location /adm/sso> 
  139: and (iii) the <IfModule !></IfModule> block would not be needed as 
  140: it is already present in /etc/httpd/conf/loncapa_apache.conf.
  141: 
  142: =head1 HANDLER SUBROUTINE
  143: 
  144: This routine is called by Apache and mod_perl.
  145: 
  146: =over 4
  147: 
  148: If $r->user is defined and requested URL is not /adm/sso or
  149: other specific URL as set by a lonOtherAuthenUrl perlvar,
  150: then redirect to /adm/sso (or to the specific URL).
  151: 
  152: Otherwise return DECLINED.
  153: 
  154: In the case of redirection a query string is appended,
  155: which will contain either (a) the originally requested URL,
  156: if not /adm/sso (or lonOtherAuthenUrl URL), and 
  157: any existing query string in the original request, or
  158: (b) if original request was for /tiny/domain/uniqueID,
  159: or if redirect is to /adm/login to support dual SSO and
  160: non-SSO, a query string which contains sso=tokenID, where the
  161: token contains information for deep-linking to course/resource. 
  162: 
  163: Support is included for use of LON-CAPA's standard log-in
  164: page -- /adm/login -- to support dual SSO and non-SSO 
  165: authentication from that "landing" page.
  166: 
  167: To enable dual SSO and non-SSO access from /adm/login
  168: a Domain Coordinator will use the web GUI:
  169: Main Menu > Set domain configuration > Display
  170: ("Log-in page options" checked) 
  171: and for any of the LON-CAPA domain's servers which
  172: will offer dual login will check "Yes" and then set:
  173: (a) SSO Text, Image, Alt Text, URL, Tool Tip
  174: (b) non-SSO: Text
  175: 
  176: The value in the URL field should be /adm/sso,
  177: or the same URL as set for the lonOtherAuthenUrl
  178: perl var, e.g., /adm/sentinel.
  179: 
  180: =back
  181: 
  182: =head1 NOTABLE SUBROUTINES
  183: 
  184: =over 4
  185: 
  186: =item set_token()
  187: 
  188: Inputs: 2
  189: $r - request object
  190: $lonhost - hostID of current server
  191: 
  192: Output: 1
  193: $querystring - query string to append to URL
  194: when redirecting.
  195: 
  196: If any of the following items are present in the original query string:
  197: role, symb, and linkkey, then they will be stored in the token file
  198: on the server, for access later to support deep-linking.  If the ltoken
  199: item is available, from successful launch from an LTI Consumer where
  200: LON-CAPA is the LTI Provider, but not configured to accept user 
  201: information, and the destination is a deep-link URL /tiny/domain/uniqueiD,
  202: then the LTI number, type (c or d), and tiny URL will be saved as the
  203: linkprot item in a token file.
  204: 
  205: =back
  206: 
  207: =cut
  208: 
  209: package Apache::lonshibauth;
  210: 
  211: use strict;
  212: use lib '/home/httpd/lib/perl/';
  213: use Apache::lonnet;
  214: use Apache::loncommon;
  215: use Apache::lonacc;
  216: use Apache::Constants qw(:common REDIRECT);
  217: use LONCAPA qw(:DEFAULT :match);
  218: 
  219: sub handler {
  220:     my $r = shift;
  221:     my $ssourl = '/adm/sso';
  222:     if ($r->dir_config('lonOtherAuthenUrl') ne '') {
  223:         $ssourl = $r->dir_config('lonOtherAuthenUrl');
  224:     }
  225:     my $target = $ssourl;
  226:     if (&Apache::lonnet::get_saml_landing()) {
  227:         $target = '/adm/login';
  228:     }
  229:     if (($r->user eq '') && ($r->uri ne $target) && ($r->uri ne $ssourl)) {
  230:         my $lonhost = $Apache::lonnet::perlvar{'lonHostID'};
  231:         my $hostname = &Apache::lonnet::hostname($lonhost);
  232:         if (!$hostname) { $hostname = $r->hostname(); }
  233:         my $protocol = $Apache::lonnet::protocol{$lonhost};
  234:         unless ($protocol eq 'https') { $protocol = 'http'; }
  235:         my $alias = &Apache::lonnet::use_proxy_alias($r,$lonhost);
  236:         if (($alias ne '') &&
  237:             (&Apache::lonnet::alias_shibboleth($lonhost))) {
  238:             $hostname = $alias;
  239:         }
  240:         my $dest = $protocol.'://'.$hostname.$target;
  241:         if ($target eq '/adm/login') {
  242:              my $querystring = &set_token($r,$lonhost);
  243:              if ($querystring ne '') {
  244:                  $dest .= '?'.$querystring;
  245:              }
  246:         } else {
  247:             my $uri = $r->uri;
  248:             if ($uri =~ m{^/tiny/$match_domain/\w+$}) {
  249:                 my $querystring = &set_token($r,$lonhost);
  250:                 if ($querystring ne '') {
  251:                     $dest .= '?'.$querystring;
  252:                 }
  253:             } else {
  254:                 if ($r->args ne '') {
  255:                     $dest .= (($dest=~/\?/)?'&':'?').$r->args;
  256:                 }
  257:                 unless (($uri eq '/adm/roles') || ($uri eq '/adm/logout')) {
  258:                     unless ($r->args =~ /origurl=/) {
  259:                         $dest.=(($dest=~/\?/)?'&':'?').'origurl='.$uri;
  260:                     }
  261:                 }
  262:             }
  263:         }
  264:         $r->header_out(Location => $dest);
  265:         return REDIRECT;
  266:     } else {
  267:         return DECLINED;
  268:     }
  269: }
  270: 
  271: sub set_token {
  272:     my ($r,$lonhost) = @_;
  273:     my ($firsturl,$querystring,$ssotoken,@names,%token);
  274:     @names = ('role','symb','ltoken','linkkey');
  275:     map { $token{$_} = 1; } @names;
  276:     unless (($r->uri eq '/adm/roles') || ($r->uri eq '/adm/logout')) {
  277:         $firsturl = $r->uri;
  278:     }
  279:     if ($r->args ne '') {
  280:         &Apache::loncommon::get_unprocessed_cgi($r->args);
  281:     }
  282:     if ($r->uri =~ m{^/tiny/$match_domain/\w+$}) {
  283:         if ($env{'form.ttoken'}) {
  284:             my %info = &Apache::lonnet::tmpget($env{'form.ttoken'});
  285:             &Apache::lonnet::tmpdel($env{'form.ttoken'});
  286:             if ($info{'ltoken'}) {
  287:                 $env{'form.ltoken'} = $info{'ltoken'};
  288:             } elsif ($info{'linkkey'} ne '') {
  289:                 $env{'form.linkkey'} = $info{'linkkey'};
  290:             }
  291:         } else {
  292:             unless (($env{'form.ltoken'}) || ($env{'form.linkkey'})) {
  293:                 &Apache::lonacc::get_posted_cgi($r,['linkkey']);
  294:             }
  295:         }
  296:     }
  297:     my $extras;
  298:     foreach my $name (@names) {
  299:         if ($env{'form.'.$name} ne '') {
  300:             if ($name eq 'ltoken') {
  301:                 my %info = &Apache::lonnet::tmpget($env{'form.ltoken'});
  302:                 &Apache::lonnet::tmpdel($env{'form.ltoken'});
  303:                 if ($info{'linkprot'}) {
  304:                     $extras .= '&linkprot='.&escape($info{'linkprot'});
  305:                     last;
  306:                 }
  307:             } else {
  308:                 $extras .= '&'.$name.'='.&escape($env{'form.'.$name});
  309:             }
  310:         }
  311:     }
  312:     if (($firsturl ne '') || ($extras ne '')) {
  313:         $extras .= ':sso';
  314:         $ssotoken = &Apache::lonnet::reply('tmpput:'.&escape($firsturl).
  315:                                            $extras,$lonhost);
  316:         $querystring = 'sso='.$ssotoken;
  317:     }
  318:     if ($r->args ne '') {
  319:         foreach my $key (sort(keys(%env))) {
  320:             if ($key =~ /^form\.(.+)$/) {
  321:                 my $name = $1;
  322:                 next if (($token{$name}) || ($name eq 'ttoken'));
  323:                 $querystring .= '&'.$name.'='.$env{$key};
  324:             }
  325:         }
  326:     }
  327:     return $querystring;
  328: }
  329: 
  330: 1;
  331: __END__