Quoting from Scott Porter's mail on Sun, Feb 24, 2002 at 03:54:20PM -0000:
Erm, I don't think you quite understood my point. I'm taking about trying to
find a cure for the problem of having huge attachments sent to me from an
infected machine (in fact, many infected machines at the moment). It's not
that I'm worried about my machines contracting a virus, it's the download
time! Many of these virii leave a signature in the body, not the head, which
is why I wondered if it would be possible to filter as the data was coming
down the pipe. There are no other solutions to this problem - it's nothing
to do with web filters or virus scanners.
Let us assume that you have a scanner+filter "S" which can reject
mails based on content before getting end-of-file.
Then, two solutions are easily possible:
1) use sendmail with filtering enabled. tell it to filter the mail
through "S". fetchmail will send the mail to sendmail which will send
it to "S". If "S" rejects the mail, so will sendmail, so will
fetchmail.
2) write a mini smtp server to run between fetchmail and your smtp
server. it should basically send the normal transaction directly to
your smtp server and the DATA through "S" to your smtp server. If "S"
rejects the mail, so should your program, so will fetchmail.
In both the above solutions, there is no need to modify fetchmail.
Also, it will work for both incoming and outgoing mails. Modifying
fetchmail will only affect mails which are being polled. Your
bandwidth could still be eaten up if your smtp server is accepting
mails from the Internet.
So, this feature should not be a fetchmail feature.
Sunil Shetye.