A webcash enabled CAPTCHA
Cashca is a proof of concept browser extension to implement a paywall or bot control on an endpoint using webcash tokens for their "proof of work". It's designed to provide low friction UI for receiving a webcash token.
A resource wishing to implement cashca needs to do the following:
- Decide on the webcash amount desired and generate a webcash token with a random 32-byte secret, i.e. (
e100:secret:001122334455...) - Embed the token in the HTML page with the tag id="cashca", i.e.
<p id="cashca">webcash_token</p>
Clicking on the cashca browser extension will parse the active tab and look for a "cashca" tag and if found will prompt the user to approve the transfer.
Once approved by the user, cashca will pay to the server generated token via a "replace" function. The server should have a "proceed" button which checks to see if the transfer has occured via a "verify" function and secure the token into its own wallet before serving the requested content.
Cashca holds webcash tokens by entering a master_secret in the browser's localStorage.
In summary, the UI is as follows when a user navigates to a website that implements cashca:
- Enter URL and load page
- Review the webcash amount
- Click on the browser extension to "pop-up" and click "pay" and then submit.
- Site takes care of the rest
The source code provided is for mozilla based browsers.
