On 2011-07-28, R0me0 *** <[email protected]> wrote: > Hello misc. > > I would like to know if is possible do the following: > > clients--------------OpenBSD_FW--------------------External_mail_server > > when clients send or receive an email, OpenBSD catch this mail and send a > copy of this to another email account, it must be transparently to user. > > Please, anybody, can indicate the correctly way to do this? > > Thanks in advanced > > Cheers, > >
dsniff has "mailsnarf" which claims to do this, it won't handle encrypted sessions even if you have the key material and I have no idea how well it can handle recent SMTP implementations. For SMTP you can run a standard MTA like Postfix and divert all connections to it and use always_bcc or similar. In some places intercepting communications will likely be illegal (at least without consent from one or possibly both parties), so do your own research as to whether you're allowed to do this. Intercepting mail like this is *very easy*. People who want to avoid having their mail intercepted in this way should 1) use encryption and 2) carefully check that they're connecting to the server which they're expecting (check certificates etc).
