postprox is an SMTP proxy which copies an SMTP
conversation between its input and another SMTP server, but spools the DATA
portion to a temporary file and runs a specified program on it before
passing it on to the output server - or outputting an SMTP error code
instead if the content filter says so.
The design aim of
postprox is to do only one
job: proxy SMTP conversations and pass message contents to another program
to determine whether to accept or reject the message. With this in mind,
postprox is small and has a minimal feature
set; its reduced complexity reduces the risk of bugs and security holes.
Comments, bug reports, and patches gratefully received - please use the Contact Form.
$OUTFILEso filtering scripts can modify the email in transit
setenv()for better portability
Things still to do: