Ultrasurf can be blocked by ufdbGuard, a free URL rewriter for Squid.
ufdbGuard uses various techniques to block Ultrasurf:
- verifying the HTTPS connections by opening a new HTTPS connection
and check if the other side speaks SSL+HTTP
- blocking HTTPS to sites without a FQDN in the URL
- blocking HTTPS to sites without a properly singed SSL certificate
Marcus
Amos Jeffries wrote:
Gerson "fserve" Barreiros wrote:
How to block ultrasurf, thor and similars using squind in transparent
mode?
Haven't heard of Thor. What does it do? references please.
UltraSurf - you can't. Its an HTTP-over-P2P proxy. Blocking requires
control of the web browser being used. At which point you are better off
dropping the transparent proxy, set the proxy settings properly and lock
them.
Amos