Synology usage series 17: Install WebDav with Lighttpd

Update Note: WebDav is officially support since Firmware 3.0. This article is useful for user who still sticking with firmware 2.x.

The benefit of WebDAV is that you can securely mount a folder of your diskstation from any machine with http/https access to the internet, without the need of installing and downloading any client software. All the works were handled by the web server and the webdav plugin. It is good for simple and quick file exchange. I know that some NAS already support WebDAV by default, Syno really should add WebDAV support by default… asap…

1. Bootstrap your diskstation
2. Install all required packages below

   # ipkg install libxml2
   # ipkg install sqlite
   # ipkg install lighttpd
   # ipkg install e2fsprogs
   

3. Edit the configuration of lighttpd.conf

   # vi /opt/etc/lighttpd/lighttpd.conf
   

   add the following line

       "mod_webdav",
   

   then make sure following lines were not commented:

   "mod_webdav",
   "mod_alias",
   "mod_access",
   'mod_auth",
   "mod_accesslog',
   

   change the web document root and port of web server, eg:

   server.document-root = “/opt/share/www”
   server.port = 81

   Append the lines below to end of the configuration file:

       #### webdav
       webdav.activate = "enable"
       webdav.is-readonly = "disable"
   
       auth.backend.activate = "enable"
       auth.backend = "htpasswd"
       auth.backend.htpasswd.userfile = "/opt/share/www/passwd/passwd.dav"
       auth.require = ( "" => ( "method" => "basic",
                                "realm" => "WebDav",
                                "require" => "valid-user" ) )
   
       #### SSL
       $SERVER["socket"] == "<internal IP of NAS>:91" {
       ssl.engine = "enable"
       ssl.pemfile = "/opt/etc/lighttpd/ssl/server.pem"
       server.document-root = "/opt/share/www/"
       server.errorlog = "/opt/var/log/lighttpd/serror.log"
       accesslog.filename = "/opt/var/log/lighttpd/saccess.log"
       }
   
   

   My reason to use port 91 instead of 443 is to avoid conflict with the apache in case you already enabled the https for your web station.

   If you prefer using 443 to ensure you can access the webdav share anywhere (some strict router do block uncommon ports, like company firewall), first disable the https for your web station and then change the value to 443 here.

   To disable the https for the web station (required ONLY if you want to use port 443 for WebDAV/Lighttpd) :

   Network Services > Web Services > HTTP Service Options

   Uncheck the Enable HTTPS connection.

   

   Synology : Disable HTTPS for web services

4. Generate SSL certificate

   # mkdir /opt/etc/lighttpd/ssl
   # cd /opt/etc/lighttpd/ssl
   # openssl req -new -x509 -keyout server.pem -out server.pem -days 365 -nodes
   # chmod 0600 server.pem
   

5. Create the password file

   # mkdir /opt/share/www/passwd
   # /usr/syno/apache/bin/htpasswd -c /opt/share/www/passwd/passwd.dav <user name>
   

   If htpasswd does not existed on your diskstation, use web based htpasswd generator instead. (My DS207+ do have the htpasswd utility, but my DS101j doesn’t)

6. Start lighttpd

       # /volume1/opt/etc/init.d/S80lighttpd start
   

7. For firmware 2.2 user, a firewall rule is required for external access of the webdav server.

   Network Services > Firewall > Click ‘Create’ button

   Ports > Check ‘Custom’ radio button > Click ‘Custom’ button

   

   Synology: Adding a new firewall rule with custom port

   To add a new custom port:

   Ports: Type: Destination Port
   Protocol: TCP
   Ports: 91 (or port 443 if you disabled HTTPS connection for web station)

   

   Synology: Adding new firewall rule for WebDAV server with https : Port 91 : TCP

   Source IP: ALL (or any other permitted IP address)

   

   DiskStation: Firewall: Assign 'ALL' for source IP

   Action : Access : Allow

   

   DiskStation: Firewall: Allow an firewall rule

8. Configure your broadband router and create a port forwarding to allow incoming https traffic to the NAS. Below is an example from linksys WRT54G router illustrating both port 91 and 443. Change the port number for your setup.
   

   linksys port forwarding for port 91 and 443