Handles passes containing cryptographically blinded tokens for bypassing Cloudflare challenge pages.
The Cloudflare Privacy Pass extension provides users with the ability to bypass Cloudflare challenge pages if they have already submitted a valid CAPTCHA solution. The extension generates passes containing cryptographically "blinded" tokens that are signed by Cloudflare's edge when a CAPTCHA is solved. These tokens are "unblinded" and stored by the extension for future use; they are redeemed automatically when a future challenge page is seen. The "blinding" procedure means that signed and redeemed tokens are cryptographically unlinkable from Cloudflare's perspective and, as such, are suitable for usage in conjunction with external anonymity measures (such as Tor/VPNs).