spfd.mail-spf-query-perl(8p)

Usage

spfd --port port [{--set-user uid | username}] [{--set-group gid | groupname}]

spfd --socket filename [{--socket-user uid | username}] [{--socket-group gid | groupname}] [--socket-perms octal-perms] [{--set-user uid | username}] [{--set-group gid | groupname}]

spfd --help

Version

2006-02-07

Overview

spfd is a simple forking Sender Policy Framework (SPF) query proxy server. spfd receives and answers SPF query requests on a TCP/IP or UNIX domain socket.

The --port form listens on a TCP/IP socket on the specified port. The default port is 5970.

The --socket form listens on a UNIX domain socket that is created with the specified filename. The socket can be assigned specific user and group ownership with the --socket-user and --socket-group options, and specific filesystem permissions with the --socket-perms option.

Generally, spfd can be instructed with the --set-user and --set-group options to drop root privileges and change to another user and group before it starts listening for requests.

The --help form prints usage information for spfd.

Request

A request consists of a series of lines delimited by \x0A (LF) characters (or whatever your system considers a newline). Each line must be of the form key=value, where the following keys are required:

`ip`	The sender IP address.
`sender`	The envelope sender address (from the SMTP `"MAIL FROM"` command).
`helo`	The envelope sender hostname (from the SMTP `"HELO"` command).

Response

spfd responds to query requests with similar series of lines of the form key=value. The most important response keys are:

result

The result of the SPF query:

pass: The specified IP address is an authorized mailer for the sender domain/address.

fail: The specified IP address is not an authorized mailer for the sender domain/address.

softfail: The specified IP address is not an authorized mailer for the sender domain/address, however the domain is still in the process of transitioning to SPF.

neutral: The sender domain makes no assertion about the status of the IP address.

unknown: The sender domain has a syntax error in its SPF record.

error: A temporary DNS error occurred while resolving the sender policy. Try again later.

none: There is no SPF record for the sender domain.

smtp_comment: The text that should be included in the receiver's SMTP response.

header_comment: The text that should be included as a comment in the message's "Received-SPF:" header.

spf_record: The SPF record of the envelope sender domain.

For the description of other response keys see Mail::SPF::Query.

For more information on SPF see <http://www.openspf.org>.

Examples

A running spfd could be tested using the "netcat" utility like this:

    $ echo -e "ip=11.22.33.44\[email protected]\nhelo=spammer.example.net\n" | nc localhost 5970
    result=neutral
    smtp_comment=Please see http://spf.pobox.com/why.html?sender=user%40pobox.com&ip=11.22.33.44&receiver=localhost
    header_comment=localhost: 11.22.33.44 is neither permitted nor denied by domain of [email protected]
    guess=neutral
    smtp_guess=
    header_guess=
    guess_tf=neutral
    smtp_tf=
    header_tf=
    spf_record=v=spf1 ?all