5-Minute WebDAV Server for Dropbox and iPad Pages, Numbers, and Keynote

This quick guide will get you set up with a secured simple WebDAV server using Ruby and Rack. The idea is to make your Dropbox accessible through WebDAV. This enables secure saving of documents from the iPad iWork apps back into your Dropbox account.

The script was inspired by Billy He’s RackDAV Thin script and improved to add self-signed certificates for an encrypted connection.

Prerequisites

This guide was written with Mac OS X in mind, but with a few changes should work on any *nix-like system. Ruby and RubyGems are assumed to be already installed.

sudo gem install rack rack_dav

Create self-signed certificates

cd ~/Dropbox
mkdir .certs
cd .certs/

openssl genrsa -des3 -out server.key 1024

openssl req -new -key server.key -out server.csr

openssl x509 -req -days 365 -in server.csr -signkey server.key -out server.crt

Remove the unnecessary PEM password unless you’re really paranoid:

cp server.key server.key.org
openssl rsa -in server.key.org -out server.key

Verbose Info: http://efreedom.com/Question/3-73979/Easily-Create-SSL-Certificate-Configure-Apache2-Mac-OS

The RackDAV script

Here’s the RackDAV script which you could save as rackdav.rb in your Dropbox folder. Replace all instances of USERNAME and PASSWORD as needed.

#!/usr/bin/env ruby
   
require 'rubygems'
require 'rack'
require 'rack_dav'
require 'webrick'
require 'webrick/https'
require 'openssl'

pkey = OpenSSL::PKey::RSA.new(File.open("/Users/USERNAME/Dropbox/.certs/server.key").read)
cert = OpenSSL::X509::Certificate.new(File.open("/Users/USERNAME/Dropbox/.certs/server.crt").read)

app = Rack::Builder.new do
  use Rack::ShowExceptions
  use Rack::CommonLogger
  use Rack::Reloader
  use Rack::Lint

  use Rack::Auth::Basic do |username, password|
    [username, password] === ['USERNAME', 'PASSWORD']
  end

  run RackDAV::Handler.new(:root => '/Users/USERNAME/Dropbox')
end.to_app

Rack::Handler::WEBrick.run(app, :Port => 1024, :SSLEnable => true, :SSLVerifyClient => OpenSSL::SSL::VERIFY_NONE, :SSLCertificate => cert, :SSLPrivateKey => pkey, :SSLCertName => [["CN",WEBrick::Utils::getservername]])

Source: This script was inspired by the one found at http://surrealtime.tumblr.com/dropbox_webdav.

Make sure it works and runs:

chmod +x rackdav.rb

sudo ./rackdav.rb

Tip: To terminate the webrick server, try ctrl+alt+c.

Starting on system boot using launchd

Edit and save this plist file in /Library/LaunchDaemons/org.YOURNAME.RackDAV.plist and don’t foreget to change ALL CAP items like USERNAME.

< ?xml version="1.0" encoding="UTF-8"?>
< !DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
	<key>ExitTimeOut</key>
		<integer>150</integer>
	<key>HopefullyExitsFirst</key>
		<true />
	<key>Label</key>
		<string>com.YOURNAME.RackDAV</string>
	<key>UserName</key>
		<string>USERNAME</string>
	<key>ProgramArguments</key>
		<array>
			<string>/usr/bin/ruby</string>
			<string>/Users/USERNAME/Dropbox/rackdav.rb</string>
		</array>
	<key>RunAtLoad</key>
		<true />
</dict>
</plist>

You can load and unload this daemon without restarting using the following commands:

sudo launchctl load -w /Library/LaunchDaemons/org.YOURNAME.RackDAV.plist

sudo launchctl unload -w /Library/LaunchDaemons/org.YOURNAME.RackDAV.plist