Eduroam METU | Notion

HTTP/HTTPS focused blocking

DNS

METU's DNS server resolves blocked domains fine.
Won't manipulate 3rd party DNS servers.

HTTP

If a blocked domain appears on host header, it will 302 redirect to Vodafone IP: http://176.55.252.4:8080/?url=<DomainName>%2F

$ curl -vik --header "Host: xvideos.com" 85.117.236.245
*   Trying 85.117.236.245:80...
* TCP_NODELAY set
* Connected to 85.117.236.245 (85.117.236.245) port 80 (#0)
> GET / HTTP/1.1
> Host: xvideos.com
> User-Agent: curl/7.68.0
> Accept: */*
> 
* Mark bundle as not supporting multiuse
< HTTP/1.1 302 Found
HTTP/1.1 302 Found
< Content-Length: 241
Content-Length: 241
< Location: <http://176.55.252.4:8080/?url=xvideos.com%2F>
Location: <http://176.55.252.4:8080/?url=xvideos.com%2F>
< Content-Type: text/html; charset=UTF-8
Content-Type: text/html; charset=UTF-8

< 
<HTML><HEAD><meta http-equiv="content-type" content="text/html;charset=utf-8">
<TITLE>302 Found</TITLE></HEAD><BODY>
<H1>302 Found</H1>
The document has moved
<A HREF="<http://176.55.252.4:8080/?url=xvideos.com%2F>">here</A>
</BODY></HTML>

* Connection #0 to host 85.117.236.245 left intact

ISP does not block the government IP address with blocked domain to present the page stating the domain is blocked.

Government's Statement of the Blocked Domains

HTTPS

If a blocked domain appears on SNI, it will get stuck after TLS client hello, SNI blocking

$ curl -vik --resolve xvideos.com:443:85.117.236.245 <https://xvideos.com> -m 2
* Added xvideos.com:443:85.117.236.245 to DNS cache
* Hostname xvideos.com was found in DNS cache
*   Trying 85.117.236.245:443...
* TCP_NODELAY set
* Connected to xvideos.com (85.117.236.245) port 443 (#0)
* ALPN, offering h2
* ALPN, offering http/1.1
* successfully set certificate verify locations:
*   CAfile: /etc/ssl/certs/ca-certificates.crt
  CApath: /etc/ssl/certs
* TLSv1.3 (OUT), TLS handshake, Client hello (1):
* Operation timed out after 2001 milliseconds with 0 out of 0 bytes received
* Closing connection 0
curl: (28) Operation timed out after 2001 milliseconds with 0 out of 0 bytes received