qmail-smtpd - receive mail via SMTP
qmail-smtpd receives mail messages via the Simple Mail Transfer Protocol
(SMTP) and invokes qmail-queue to deposit them into the outgoing queue.
qmail-smtpd must be supplied several environment variables; see
tcp-environ(5).
qmail-smtpd is responsible for counting hops. It rejects
any message with 100 or more Received or Delivered-To header
fields.
qmail-smtpd supports ESMTP, including the 8BITMIME and
PIPELINING options.
qmail-smtpd converts the SMTP newline convention into the UNIX newline
convention by converting CR LF into LF. It returns a temporary error and drops
the connection on bare LFs; see http://pobox.com/~djb/docs/smtplf.html.
qmail-smtpd accepts messages that contain long lines or
non-ASCII characters, even though such messages violate the SMTP
protocol.
- badmailfrom
- Unacceptable envelope sender addresses. qmail-smtpd will reject
every recipient address for a message if the envelope sender address is
listed in badmailfrom. A line in badmailfrom may be of the
form @host, meaning every address at
host.
- databytes
- Maximum number of bytes allowed in a message, or 0 for no limit. Default:
0. If a message exceeds this limit, qmail-smtpd returns a permanent
error code to the client; in contrast, if the disk is full or
qmail-smtpd hits a resource limit, qmail-smtpd returns a
temporary error code.
databytes counts bytes as stored on disk, not as
transmitted through the network. It does not count the
qmail-smtpd Received line, the qmail-queue Received line,
or the envelope.
If the environment variable DATABYTES is set, it
overrides databytes.
- localiphost
- Replacement host name for local IP addresses. Default: me, if that
is supplied. qmail-smtpd is responsible for recognizing
dotted-decimal addresses for the current host. When it sees a recipient
address of the form box@[d.d.d.d], where d.d.d.d is a local
IP address, it replaces [d.d.d.d] with localiphost. This is
done before rcpthosts.
- morercpthosts
- Extra allowed RCPT domains. If rcpthosts and morercpthosts
both exist, morercpthosts is effectively appended to
rcpthosts.
You must run qmail-newmrh whenever morercpthosts
changes.
Rule of thumb for large sites: Put your 50 most commonly used
domains into rcpthosts, and the rest into
morercpthosts.
- rcpthosts
- Allowed RCPT domains. If rcpthosts is supplied, qmail-smtpd
will reject any envelope recipient address with a domain not listed in
rcpthosts.
Exception: If the environment variable RELAYCLIENT is
set, qmail-smtpd will ignore rcpthosts, and will append
the value of RELAYCLIENT to each incoming recipient address.
rcpthosts may include wildcards:
heaven.af.mil
.heaven.af.mil
Envelope recipient addresses without @ signs are always
allowed through.
- smtpgreeting
- SMTP greeting message. Default: me, if that is supplied; otherwise
qmail-smtpd will refuse to run. The first word of
smtpgreeting should be the current host's name.
- timeoutsmtpd
- Number of seconds qmail-smtpd will wait for each new buffer of data
from the remote SMTP client. Default: 1200.
tcp-env(1), tcp-environ(5), qmail-control(5), qmail-inject(8), qmail-newmrh(8),
qmail-queue(8), qmail-remote(8)