Bug 16818: External auth redirect broken under Plack

Test plan:

0) Have either CAS or Shibboleth authentication enabled under Plack.
1) Hover over the authentication link on the staff client or OPAC, and
   notice that it has either '.../opac/...' or '.../intranet/...' instead
   of '.../cgi-bin/koha/...'. (This will be a complete dealbreaker for CAS
   authentication.)
2) Apply patch.
3) Check links again; they should now have the correct paths.

Signed-off-by: Matthias Meusburger <matthias.meusburger@biblibre.com>

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Did not test CAS or Shibboleth, but no regression found.

Signed-off-by: Brendan Gallagher <brendan@bywatersolutions.com>

C4/Auth.pm

@@ -32,7 +32,7 @@ use C4::Languages;
 use C4::Branch;       # GetBranches
 use C4::Search::History;
 use Koha;
-use Koha::AuthUtils qw(hash_password);
+use Koha::AuthUtils qw(get_script_name hash_password);
 use Koha::LibraryCategories;
 use Koha::Libraries;
 use POSIX qw/strftime/;
@@ -194,7 +194,7 @@ sub get_template_and_user {
 
             $template->param(
                 loginprompt => 1,
-                script_name => _get_script_name(),
+                script_name => get_script_name(),
             );
             print $in->{query}->header(
                 {   type              => 'text/html',
@@ -1211,7 +1211,7 @@ sub checkauth {
         opaclayoutstylesheet                  => C4::Context->preference("opaclayoutstylesheet"),
         login                                 => 1,
         INPUTS                                => \@inputs,
-        script_name                           => _get_script_name(),
+        script_name                           => get_script_name(),
         casAuthentication                     => C4::Context->preference("casAuthentication"),
         shibbolethAuthentication              => $shib,
         SessionRestrictionByIP                => C4::Context->preference("SessionRestrictionByIP"),
@@ -2050,24 +2050,6 @@ sub getborrowernumber {
     return 0;
 }
 
-=head2 _get_script_name
-
-This returns the correct script name, for use in redirecting back to the correct page after showing
-the login screen. It depends on details of the package Plack configuration, and should not be used
-outside this context.
-
-=cut
-
-sub _get_script_name {
-    # This is the method about.pl uses to detect Plack; now that two places use it, it MUST be
-    # right.
-    if ( ( any { /(^psgi\.|^plack\.)/i } keys %ENV ) && $ENV{SCRIPT_NAME} =~ m,^/(intranet|opac)(.*), ) {
-        return '/cgi-bin/koha' . $2;
-    } else {
-        return $ENV{SCRIPT_NAME};
-    }
-}
-
 END { }    # module clean-up code here (global destructor)
 1;
 __END__

C4/Auth_with_cas.pm

@@ -22,6 +22,7 @@ use warnings;
 
 use C4::Debug;
 use C4::Context;
+use Koha::AuthUtils qw(get_script_name);
 use Authen::CAS::Client;
 use CGI qw ( -utf8 );
 use FindBin;
@@ -203,7 +204,7 @@ sub _url_with_get_params {
     my $type = shift;
 
     my $uri_base_part = ($type eq 'opac') ?
-                        C4::Context->preference('OPACBaseURL') . $query->script_name():
+                        C4::Context->preference('OPACBaseURL') . get_script_name() :
                         C4::Context->preference('staffClientBaseURL');
 
     my $uri_params_part = '';

C4/Auth_with_shibboleth.pm

@@ -21,6 +21,7 @@ use Modern::Perl;
 
 use C4::Debug;
 use C4::Context;
+use Koha::AuthUtils qw(get_script_name);
 use Koha::Database;
 use Carp;
 use CGI;
@@ -57,7 +58,7 @@ sub logout_shib {
 sub login_shib_url {
     my ($query) = @_;
 
-    my $param = _get_uri() . $query->script_name();
+    my $param = _get_uri() . get_script_name();
     if ( $query->query_string() ) {
         $param = $param . '%3F' . $query->query_string();
     }

Koha/AuthUtils.pm

@@ -21,10 +21,11 @@ use Modern::Perl;
 use Crypt::Eksblowfish::Bcrypt qw(bcrypt en_base64);
 use Encode qw( encode is_utf8 );
 use Fcntl qw/O_RDONLY/; # O_RDONLY is used in generate_salt
+use List::MoreUtils qw/ any /;
 
 use base 'Exporter';
 
-our @EXPORT_OK   = qw(hash_password);
+our @EXPORT_OK   = qw(hash_password get_script_name);
 
 =head1 NAME
 
@@ -132,6 +133,25 @@ sub generate_salt {
     close SOURCE;
     return $string;
 }
+
+=head2 get_script_name
+
+This returns the correct script name, for use in redirecting back to the correct page after showing
+the login screen. It depends on details of the package Plack configuration, and should not be used
+outside this context.
+
+=cut
+
+sub get_script_name {
+    # This is the method about.pl uses to detect Plack; now that two places use it, it MUST be
+    # right.
+    if ( ( any { /(^psgi\.|^plack\.)/i } keys %ENV ) && $ENV{SCRIPT_NAME} =~ m,^/(intranet|opac)(.*), ) {
+        return '/cgi-bin/koha' . $2;
+    } else {
+        return $ENV{SCRIPT_NAME};
+    }
+}
+
 1;
 
 __END__