[Esd-l] Case for repetitive rule.

John D. Hardin jhardin at impsec.org
Tue Nov 11 17:38:25 PST 2003

On Tue, 11 Nov 2003, Simon Matthews wrote:

> > > "Apply this rule after the message arrives
> > > Where the From line contains validuser at income.com.sg'
> > > Forward it to validuser at income.com.sg "
> >
> >One possibility, off the top of my head (and thus untested):
> >
> ><SNIP>
> I don't think this is needed. Postfix has configurable limits. In
> this case, there is a limit on the user's mailbox size. The loop
> will keep happening until the user's mailbox reaches the maximum.
> It should not crash or affect the server.  I assume Sendmail has
> similar configurable limits.

It also depends on whether this happens from malice or stupidity, and
the sequence of operations in the mail client.

For example, if the user sets their mailer to delete messages from the
mailbox as they are retrieved, then the MTA's mailbox size limits may
never kick in to prevent this. Remember, it's the *mail client* that's
doing the forwarding. It may retrieve everything, clear the retrieved
messages, and then process it's outbound spool.

This, however, means the user is probably only effectively DoSing
their own workstation disk space.

 John Hardin KA7OHZ    ICQ#15735746    http://www.impsec.org/~jhardin/
 jhardin at impsec.org                        pgpk -a jhardin at impsec.org
 key: 0xB8732E79 - 2D8C 34F4 6411 F507 136C  AF76 D822 E6E6 B873 2E79
 "To disable the Internet to save EMI and Disney is the moral
  equivalent of burning down the library of Alexandria to ensure the
  livelihood of monastic scribes."
                                    -- John Ippolito of the Guggenheim
   36 days until The Return of the King

More information about the esd-l mailing list