On Sun, 2006-01-22 at 22:16 +0530, Ankush Grover wrote: > > > On 1/22/06, Paul Howarth <paul@xxxxxxxxxxxx> wrote: > On Sun, 2006-01-22 at 15:33 +0530, Ankush Grover wrote: > > hey friends, > > > > I am using postfix on FC3 and my friend is using sendmail > on rh9 in > > his office. > > > > > > I wanted to restrict some users from > sending/receiving attachments. > > > > > > How can I restrict users from sending/receiving attachments > on postfix > > and on sendmail(for my friend). > > > > Whilst you might be able to use a milter or equivalent to > prevent > MIME-formatted attachments from being sent, this wouldn't > prevent people > sending attachments the "old-fashioned way", by uuencoding > their file > and pasting straight into the text of the mail message. > > What are you *really* trying to prevent? > > > My friend's office management has ordered him to ban some users from > sending attachments. As he is using sendmail and I am using postfix.So > I was curious to know how to prevent the same in postfix. > > He needed that kind of setup not me but still it is good to know how > one can do it in postfix. My point was that it's virtually impossible to do this because attachments can be split up into multiple emails (thus getting around size restrictions) and can be included in (say) uuencode format in the message body rather than using a MIME-style attachment. In fact, that's how most people used to send large files over email before MIME came along. There must be an underlying reason why a ban on attachments is wanted (e.g. prevent sending confidential data, prevent sending viruses) and it might be better to attack the issue directly rather than in a roundabout way by trying to ban attachments. Paul.
