Customized authentication for socks proxy

The project is to enable a paywall (captive portal) solution for the danted socks proxy on linux. This means users who want to use the proxy will automatically be shown a page where they will need to enter an access code or token (which they can buy using mobile payment). The token can give them access for 1 day or 1 week or 1 month. This needs to be done in a similar way to captive portals that run on wi-fi hotspots, except this will be running on a socks proxy server. You are free to choose an alternative proxy server like ss5. The deliverables will be - 1. Enabling captive portal/paywall for the proxy server 2. Enabling authentication by token 3. Enabling payment mechanism to buy the token The code must be written so that it is easily deployable together with the proxy software. -- This is to add a note that either danted,ss5 or even the http squid proxy are acceptable. -- 7/10/11 -- This is to add another note that username/password authentication is acceptable as an alternative to voucher/token based authentication. --