Sendmail ignores hosts.allow

[Alex Zbyslaw]

Maxim Khitrov wrote:

> I'm not sure I understand what you mean... I'm not using inetd, and
> the default configuration doesn't block sendmail from all remote
> hosts. The ssh server is running all by itself, same as sendmail. The
> way I understand it is that as long as the server was compiled with
> tcp wrappers, it should follow the rules in hosts.allow.

Sendmail is different from other network apps in that it does not block 
the connection when a deny rule is in effect, instead it send some kind 
of reject code (5xx) during the SMTP conversation.

If you check /var/log/maillog you may well see this happening.

If you search the mail archives (or try google) with some appropriate 
keywords then you should find a post from Matthew Seaman which explains 
it in detail  You could also search the source code, if you are somewhat 
C literate.

If you want to completely block connections from specific hosts (or only 
allow specific hosts) then I would suggest doing that with firewall rules.

Didn't follow the start of the thread very closely so I hope I got the 
right end of the stick.

--Alex