No but look, they're blocking connections country-wide. Apparently they have government boxes installed on the outside lines. If you're looking at IP headers and deciding to drop or pass based on that, it's trivial to collect the IPs you don't yet know, check if they're running a proxy (Signal, Tor, I2P, whatever), then add them to the block list if they are.

If it's trivial to figure out (by doing a nice handshake) whether something is a certain kind of proxy, then the cat-and-mouse game is reduced from finding lots of mice to updating the cat system to test whether passing animals are mice and instantly wiping out the mice population.

This is the very same problem that Tor faced when Tor bridge use started to pick up in China around the late 2000s / early 2010s. You only needed a single Chinese user to connect to your server for it to be probed by the Chinese censors. Older versions of the obfs Tor bridge protocol could be detected by active probes and thus blocked very much like these Signal proxies. This is a cat and mouse game that Signal could very easily lose should Iran start to care about probing all new active connections that leave Iran.

> there isn't

YET. I wonder if someone will find a simple way to map these with shodan.