How to make Subversion use Linux system accounts for authentication?

Question

I've set up a Ubuntu Server for Subversion with Apache/WebDAV interface to share repositories with other developers. My question is, how can I make Subversion use the linux system accounts for authentication? This would lead to very easy Subversion account management. Subversion with Apache/WebDAV is currently working with this configuration:

Contents of /etc/apache2/mods-available/dav_svn.conf:

<Location /svn>
  DAV svn
  SVNParentPath /home/svn
  SVNListParentPath On
  AuthType Basic
  AuthName "Subversion Repository"
  AuthUserFile /etc/apache2/dav_svn.passwd
  Require valid-user
</Location>

I have tried changing AuthUserFile /etc/apache2/dav_svn.passwd with AuthUserFile /etc/shadow with no success. This makes the server to respond with a error 500 internal server error. It's logical, why the Web service should have access to system authentication file?

Thanks a lot in advance!

Answer 1

Ok! I did it! And I thought it would be very hard to find the answer!

We have to tell Apache to use an "external authentication provider", Apache won't be checking for authentication, but will delegate the task to an external authenticator, in this case, the marvellous pwauth.

So the steps I did to make it work was:

1. Install Mod_Auth_External module for Apache2 and pwauth

   sudo apt-get install libapache2-mod-authnz-external pwauth
   

2. Enabled the new module for Apache: sudo a2enmod authnz_external in terminal.

3. Configured my apache.conf (or you may have httpd.conf) to add the external authenticator (based on this article):

   AddExternalAuth pwauth /usr/local/libexec/pwauth
   SetExternalAuthMethod pwauth pipe
   

4. Edited my /etc/apache2/mods-available/dav_svn.conf to set the new external auth provider:

   ...
   AuthType Basic
   AuthName "Subversion Repository"
   AuthBasicProvider external
   AuthExternal pwauth
   Require valid-user
   ...
   

5. Tested and worked fine!