gitweb: Add a per-repository authorization hook.

Add a configuration variable that can be used to specify an
arbitrary subroutine that will be called in the same situations
where $export_ok is checked, and its return value used
to decide whether the repository is to be shown.

This allows the user to implement custom authentication
schemes, for example by issuing a subrequest through mod_perl
and checking if Apache will authorize it.

Signed-off-by: Alexander Gavrilov <angavrilov@gmail.com>
Acked-by: Jakub Narebski <jnareb@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 21 insertions, 0 deletions

diff --git a/gitweb/INSTALL b/gitweb/INSTALL
index 26967e201a..18c9ce35e8 100644
--- a/gitweb/INSTALL
+++ b/gitweb/INSTALL
@@ -166,6 +166,27 @@ Gitweb repositories
   shows repositories only if this file exists in its object database
   (if directory has the magic file named $export_ok).
 
+- Finally, it is possible to specify an arbitrary perl subroutine that
+  will be called for each project to determine if it can be exported.
+  The subroutine receives an absolute path to the project as its only
+  parameter.
+
+  For example, if you use mod_perl to run the script, and have dumb
+  http protocol authentication configured for your repositories, you
+  can use the following hook to allow access only if the user is
+  authorized to read the files:
+
+    $export_auth_hook = sub {
+        use Apache2::SubRequest ();
+        use Apache2::Const -compile => qw(HTTP_OK);
+        my $path = "$_[0]/HEAD";
+        my $r    = Apache2::RequestUtil->request;
+        my $sub  = $r->lookup_file($path);
+        return $sub->filename eq $path
+            && $sub->status == Apache2::Const::HTTP_OK;
+    };
+
+
 Generating projects list using gitweb
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~