Re: [squid-users] Can squid be configured as SMTP/SMTPS proxy?

From: Leonardo Rodrigues <leolistas_at_solutti.com.br>
Date: Thu, 30 Sep 2010 17:17:27 -0300

  Em 30/09/2010 13:38, Alona Rossen escreveu:
> Can squid be configured as SMTP/SMTPS proxy?
>

     squid is NOT a native smtp proxy.

     altough, with the CONNECT method, most used by https connection on
squid context, you can connect in any port and, indeed, you can have a
SMTP session through squid. For that you would need:

1) ACLs that allows CONNECT to TCP port 25 ... default configurations,
SSL_Ports acl specifically, do not allow that
2) your smtp/smtps/whatever client would need to know how to tunnel
connections through an https proxy

     if you can acchieve both (#1 is easy, it depends only on some few
configurations), you could successfully tunnel ANY protocol through
squid using CONNECT method, including your smtp and smtps.

     in the past (and probably nowadays also) there were several
virus/zombies that search for open http/https proxy machines and, if
found, send spam mail through them using exactly CONNECT to TCP 25 ports
of servers and, when connected, deliver the SPAMs. This is REAL, this
happened and probably also happens nowadays. And that said, with a
capable smtp/smtps/pop3/pop3s/imap4/imap4s/whatever client, you CAN
tunnel those connections successfully through squid !

-- 
	Atenciosamente / Sincerily,
	Leonardo Rodrigues
	Solutti Tecnologia
	http://www.solutti.com.br
	Minha armadilha de SPAM, NÃO mandem email
	gertrudes_at_solutti.com.br
	My SPAMTRAP, do not email it
Received on Thu Sep 30 2010 - 20:17:47 MDT

This archive was generated by hypermail 2.2.0 : Fri Oct 01 2010 - 12:00:04 MDT