Intro

Due to mass censorship on the both sides of Russian reality, I want to have some semi/fully automatic solution to bypass them. This is it :)

DeBlocker is a simple and fully automatic service for generating eBGP prefixes of blocked "sites" that you use.

How it works

A flowchart is worth a thousand words so let's begin from it:

As you can see DeBlocker has a couple of parts:

• DNS server that:
  • exports A/AAAA answers into BGP if we think that requested site must go over VPN
  • schedules HTTPS site checker to make a decision
• HTTPS checker just make two HTTP requests - one over VPN interface and one over direct interface. After that, makes decision.
• BGP server that exports "blocked" prefixes from HTTPS checker or DNS server

So when I execute curl https://docs.splunk.com:

• curl resolves docs.splunk.com through DeBlocker DNS server that:
  • checks it and must choose the VPN direction
  • adds eBGP path for all the IP addresses that points to *.splunk.com
• and makes a TCP connection that will be routed over VPN
• that's all, pretty simple

Of course sometimes I need to send request one more time, but this is not annoying me.

Configuration

The full config can be found here

It is assumed that:

• eth0 - interface with direct connection
• eu - interface with VPN connection. I prefer WireGuard, but you can use what you need
• 65543 - DeBlocker ASN
• 65542 - dynamic neighbor ASN

So, you have to:

• configure interfaces ;)
• add the BGP neighbor on your router
• use DeBlocker DNS at home
• that's all, folks :)

P.S.