C4/Auth_with_cas.pm

   1 package C4::Auth_with_cas;
   2
   3 # Copyright 2009 BibLibre SARL
   4 #
   5 # This file is part of Koha.
   6 #
   7 # Koha is free software; you can redistribute it and/or modify it
   8 # under the terms of the GNU General Public License as published by
   9 # the Free Software Foundation; either version 3 of the License, or
  10 # (at your option) any later version.
  11 #
  12 # Koha is distributed in the hope that it will be useful, but
  13 # WITHOUT ANY WARRANTY; without even the implied warranty of
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  15 # GNU General Public License for more details.
  16 #
  17 # You should have received a copy of the GNU General Public License
  18 # along with Koha; if not, see <http://www.gnu.org/licenses>.
  19
  20 use strict;
  21 use warnings;
  22
  23 use C4::Debug;
  24 use C4::Context;
  25 use Koha::AuthUtils qw(get_script_name);
  26 use Authen::CAS::Client;
  27 use CGI qw ( -utf8 );
  28 use FindBin;
  29 use YAML;
  30
  31
  32 use vars qw(@ISA @EXPORT @EXPORT_OK %EXPORT_TAGS $debug);
  33
  34 BEGIN {
  35     require Exporter;
  36     $debug = $ENV{DEBUG};
  37     @ISA   = qw(Exporter);
  38     @EXPORT = qw(check_api_auth_cas checkpw_cas login_cas logout_cas login_cas_url logout_if_required);
  39 }
  40 my $defaultcasserver;
  41 my $casservers;
  42 my $yamlauthfile = C4::Context->config('intranetdir') . "/C4/Auth_cas_servers.yaml";
  43
  44
  45 # If there's a configuration for multiple cas servers, then we get it
  46 if (multipleAuth()) {
  47     ($defaultcasserver, $casservers) = YAML::LoadFile($yamlauthfile);
  48     $defaultcasserver = $defaultcasserver->{'default'};
  49 } else {
  50 # Else, we fall back to casServerUrl syspref
  51     $defaultcasserver = 'default';
  52     $casservers = { 'default' => C4::Context->preference('casServerUrl') };
  53 }
  54
  55 =head1 Subroutines
  56
  57 =cut
  58
  59 # Is there a configuration file for multiple cas servers?
  60 sub multipleAuth {
  61     return (-e qq($yamlauthfile));
  62 }
  63
  64 # Returns configured CAS servers' list if multiple authentication is enabled
  65 sub getMultipleAuth {
  66    return $casservers;
  67 }
  68
  69 # Logout from CAS
  70 sub logout_cas {
  71     my ($query, $type) = @_;
  72     my ( $cas, $uri ) = _get_cas_and_service($query, undef, $type);
  73     $uri =~ s/\?logout\.x=1//; # We don't want to keep triggering a logout, if we got here, the borrower is already logged out of Koha
  74     print $query->redirect( $cas->logout_url(url => $uri));
  75 }
  76
  77 # Login to CAS
  78 sub login_cas {
  79     my ($query, $type) = @_;
  80     my ( $cas, $uri ) = _get_cas_and_service($query, undef, $type);
  81     print $query->redirect( $cas->login_url($uri));
  82 }
  83
  84 # Returns CAS login URL with callback to the requesting URL
  85 sub login_cas_url {
  86     my ( $query, $key, $type ) = @_;
  87     my ( $cas, $uri ) = _get_cas_and_service( $query, $key, $type );
  88     return $cas->login_url($uri);
  89 }
  90
  91 # Checks for password correctness
  92 # In our case : is there a ticket, is it valid and does it match one of our users ?
  93 sub checkpw_cas {
  94     $debug and warn "checkpw_cas";
  95     my ($dbh, $ticket, $query, $type) = @_;
  96     my $retnumber;
  97     my ( $cas, $uri ) = _get_cas_and_service($query, undef, $type);
  98
  99     # If we got a ticket
 100     if ($ticket) {
 101         $debug and warn "Got ticket : $ticket";
 102
 103         # We try to validate it
 104         my $val = $cas->service_validate($uri, $ticket );
 105
 106         # If it's valid
 107         if ( $val->is_success() ) {
 108
 109             my $userid = $val->user();
 110             $debug and warn "User CAS authenticated as: $userid";
 111
 112             # we should store the CAS ticekt too, we need this for single logout https://apereo.github.io/cas/4.2.x/protocol/CAS-Protocol-Specification.html#233-single-logout
 113
 114             # Does it match one of our users ?
 115             my $sth = $dbh->prepare("select cardnumber from borrowers where userid=?");
 116             $sth->execute($userid);
 117             if ( $sth->rows ) {
 118                 $retnumber = $sth->fetchrow;
 119                 return ( 1, $retnumber, $userid, $ticket );
 120             }
 121             $sth = $dbh->prepare("select userid from borrowers where cardnumber=?");
 122             $sth->execute($userid);
 123             if ( $sth->rows ) {
 124                 $retnumber = $sth->fetchrow;
 125                 return ( 1, $retnumber, $userid, $ticket );
 126             }
 127
 128             # If we reach this point, then the user is a valid CAS user, but not a Koha user
 129             $debug and warn "User $userid is not a valid Koha user";
 130
 131         } else {
 132             $debug and warn "Problem when validating ticket : $ticket";
 133             $debug and warn "Authen::CAS::Client::Response::Error: " . $val->error() if $val->is_error();
 134             $debug and warn "Authen::CAS::Client::Response::Failure: " . $val->message() if $val->is_failure();
 135             $debug and warn Data::Dumper::Dumper($@) if $val->is_error() or $val->is_failure();
 136             return 0;
 137         }
 138     }
 139     return 0;
 140 }
 141
 142 # Proxy CAS auth
 143 sub check_api_auth_cas {
 144     $debug and warn "check_api_auth_cas";
 145     my ($dbh, $PT, $query, $type) = @_;
 146     my $retnumber;
 147     my ( $cas, $uri ) = _get_cas_and_service($query, undef, $type);
 148
 149     # If we have a Proxy Ticket
 150     if ($PT) {
 151         my $r = $cas->proxy_validate( $uri, $PT );
 152
 153         # If the PT is valid
 154         if ( $r->is_success ) {
 155
 156             # We've got a username !
 157             $debug and warn "User authenticated as: ", $r->user, "\n";
 158             $debug and warn "Proxied through:\n";
 159             $debug and warn "  $_\n" for $r->proxies;
 160
 161             my $userid = $r->user;
 162
 163             # we should store the CAS ticket too, we need this for single logout https://apereo.github.io/cas/4.2.x/protocol/CAS-Protocol-Specification.html#233-single-logout
 164
 165             # Does it match one of our users ?
 166             my $sth = $dbh->prepare("select cardnumber from borrowers where userid=?");
 167             $sth->execute($userid);
 168             if ( $sth->rows ) {
 169                 $retnumber = $sth->fetchrow;
 170                 return ( 1, $retnumber, $userid, $PT );
 171             }
 172             $sth = $dbh->prepare("select userid from borrowers where cardnumber=?");
 173             return $r->user;
 174             $sth->execute($userid);
 175             if ( $sth->rows ) {
 176                 $retnumber = $sth->fetchrow;
 177                 return ( 1, $retnumber, $userid, $PT );
 178             }
 179
 180             # If we reach this point, then the user is a valid CAS user, but not a Koha user
 181             $debug and warn "User $userid is not a valid Koha user";
 182
 183         } else {
 184             $debug and warn "Proxy Ticket authentication failed";
 185             return 0;
 186         }
 187     }
 188     return 0;
 189 }
 190
 191 # Get CAS handler and service URI
 192 sub _get_cas_and_service {
 193     my $query = shift;
 194     my $key   = shift;    # optional
 195     my $type  = shift;
 196
 197     my $uri = _url_with_get_params($query, $type);
 198
 199     my $casparam = $defaultcasserver;
 200     $casparam = $query->param('cas') if defined $query->param('cas');
 201     $casparam = $key if defined $key;
 202     my $cas = Authen::CAS::Client->new( $casservers->{$casparam} );
 203
 204     return ( $cas, $uri );
 205 }
 206
 207 # Get the current URL with parameters contained directly into URL (GET params)
 208 # This method replaces $query->url() which will give both GET and POST params
 209 sub _url_with_get_params {
 210     my $query = shift;
 211     my $type = shift;
 212
 213     my $uri_base_part =
 214       ( $type eq 'opac' )
 215       ? C4::Context->preference('OPACBaseURL')
 216       : C4::Context->preference('staffClientBaseURL');
 217     $uri_base_part .= get_script_name();
 218
 219     my $uri_params_part = '';
 220     foreach my $param ( $query->url_param() ) {
 221         # url_param() always returns parameters that were deleted by delete()
 222         # This additional check ensure that parameter was not deleted.
 223         my $uriPiece = $query->param($param);
 224         if ($uriPiece) {
 225             $uri_params_part .= '&' if $uri_params_part;
 226             $uri_params_part .= $param . '=';
 227             $uri_params_part .= URI::Escape::uri_escape( $uriPiece );
 228         }
 229     }
 230     $uri_base_part .= '?' if $uri_params_part;
 231
 232     return $uri_base_part . $uri_params_part;
 233 }
 234
 235 =head2 logout_if_required
 236
 237     If using CAS, this subroutine will trigger single-signout of the CAS server.
 238
 239 =cut
 240
 241 sub logout_if_required {
 242     my ( $query ) = @_;
 243     # Check we havent been hit by a logout call
 244     my $xml = $query->param('logoutRequest');
 245     return 0 unless $xml;
 246
 247     my $dom = XML::LibXML->load_xml(string => $xml);
 248     my $ticket;
 249     foreach my $node ($dom->findnodes('/samlp:LogoutRequest')){
 250         # We got a cas single logout request from a cas server;
 251         $ticket = $node->findvalue('./samlp:SessionIndex');
 252     }
 253
 254     return 0 unless $ticket;
 255
 256     # We've been called as part of the single logout destroy the session associated with the cas ticket
 257     my $params = C4::Auth::_get_session_params();
 258     my $success = CGI::Session->find( $params->{dsn}, sub {delete_cas_session(@_, $ticket)}, $params->{dsn_args} );
 259
 260     print $query->header;
 261     exit;
 262 }
 263
 264 sub delete_cas_session {
 265     my $session = shift;
 266     my $ticket = shift;
 267     if ($session->param('cas_ticket') && $session->param('cas_ticket') eq $ticket ) {
 268         $session->delete;
 269         $session->flush;
 270     }
 271 }
 272
 273 1;
 274 __END__
 275
 276 =head1 NAME
 277
 278 C4::Auth - Authenticates Koha users
 279
 280 =head1 SYNOPSIS
 281
 282   use C4::Auth_with_cas;
 283
 284 =cut
 285
 286 =head1 SEE ALSO
 287
 288 CGI(3)
 289
 290 Authen::CAS::Client
 291
 292 =cut