Que tipo de mágica meu ISP está fazendo? [fechadas]

Question

Ao tentar configurar o OpenDNS e não conseguir fazer com que a filtragem de sites realmente funcione, percebi que meu ISP está fazendo algo nefasto com todas as solicitações HTTP. Para encurtar a história, se houver um cabeçalho Host: , não importa qual endereço IP eu uso, o site que recebo depende do cabeçalho Host: e nada mais.

Ele também parece usar automaticamente o HTTP / 1.1, mesmo se eu especificar HTTP / 1.0 no pedido.

Exemplos:

Conecte-se a google.com com Host: yahoo.com

$ echo -e "HEAD / HTTP/1.0\r\nHost: yahoo.com\r\n\r\n" | nc google.com 80
HTTP/1.1 301 Moved Permanently
Date: Mon, 02 Jan 2012 10:50:13 GMT
Location: http://www.yahoo.com/
Vary: Accept-Encoding
Content-Type: text/html; charset=utf-8
Cache-Control: private
Age: 0
Server: YTS/1.20.0
Connection: close

$

Conecte-se a um endereço IP inválido com Host: yahoo.com

$ echo -e "HEAD / HTTP/1.0\r\nHost: yahoo.com\r\n\r\n" | nc 1.0.0.0 80
HTTP/1.1 301 Moved Permanently
Date: Mon, 02 Jan 2012 10:51:02 GMT
Location: http://www.yahoo.com/
Vary: Accept-Encoding
Content-Type: text/html; charset=utf-8
Cache-Control: private
Age: 0
Server: YTS/1.20.0
Connection: close

$

Então, o que o meu provedor está fazendo? E eu deveria reclamar com eles?

    

Answer 1

O seu ISP está usando o proxy transparente: link

    

Answer 2

Acho que você perdeu a FAQ do OpenDNS:

Is OpenDNS running a proxy?

Yes, sometimes. OpenDNS runs a simple proxy in certain circumstances. Some Internet browsers and many toolbars intercept requests made from the address bar, which prevents initiation of a proper DNS request. Our proxy ensures that your requests are routed properly when using OpenDNS services.

And, like all OpenDNS services, the proxy is respectful of and works hard to protect your privacy. We do not track the DNS requests that are routed through the proxy. In fact, since so many people use toolbars, the proxy must automatically rotate and delete the logs, and this happens frequently.

OpenDNS does not store or mine any of the data that passes through our proxy. The proxy does nothing malicious – it is designed to ensure OpenDNS services work with all browsers and toolbars.