Re: notion of a local address [was: Re: ioctl SIOCGIFNETMASK: ip alias

[Wietse Venema]

Andrey Savochkin:
> > That is not practical. Surely there is an API to find out if an IP
> > address connects to the machine itself. If every UNIX system on
> > this planet can do it, then surely Linux can do it.
> 
> Let me correct you: you need to recognize not addresses that result in
> connecting to the _machine_ itself, but connecting to the same _MTA_.

The SMTP RFC requires that user@[ip.address] is correctly recognized
as a final destination.  This requires that Linux provides the MTA
with information about IP addresses that correspond with INADDR_ANY.

I am susprised that it is not possible to ask such information up
front (same with netmasks), and that an application has to actually
query a complex oracle, again and again, for every IP address.

	Wietse