Table of Contents
The Synchronet Mail Server is responsible for incoming and outgoing Internet e-mail.
The mail server accepts submissions via the SMTP and ESMTP protocols, by default, on TCP ports 25 and 587.
By default, the mail server does not allow relaying of mail from unauthenticated clients to external mail servers.
The SMTP server supports authentication via the PLAIN, LOGIN, or CRAM-MD5 SMTP-AUTH methods (client chooses).
The SMTP server does not at this time support SMTP-TLS sessions.
The SMTP server can service multiple simultaneous incoming sessions and messages, with multiple recipients per message.
The SMTP server also supports the SEND, SAML and SOML commands for delivering instant messages (a.k.a. telegrams) to users of the BBS.
Recipient mail addresses can have special prefixes to direct the routing of the incoming mail:
|local:|| ||Deliver to local mailbox only, do not forward to external mail/netmail address|
|forward:|| ||Forward to the destination user's external mail/netmail address|
|sub:|| ||Post email contents as message on message sub-board (specified by internal code)|
|qwk-id!|| ||Routes to <user> at QWKnet node with specified QWK-ID (may include a full slash-separated route)|
It is sometimes preferred to use an alias (configured in the
ctrl/alias.cfg file) to allow the reception of a more “normal” looking email address and route to the Specially-Prefixed address. The following examples allows the reception of email sent to “cnnreport@<yourbbs>” and forwards the message to the message sub-board with the internal code of
Incoming email is scanned for To: headers in the format
Tag is extracted, and if it is not found in
data/user/<usernum>.smtptags it is
sent to the user. If it DOES match a line in the smtptags file, the email
is rejected with a “no such user” error.
Using this this feature allows you (the sysop) to easily create “temporary” email addresses. Once you start recieving spam on one tag, just disable it.
The SendMail Thread is responsible for delivering mail using the SMTP or ESMTP protocols, optionally authenticating using PLAIN, LOGIN, or CRAM-MD5 SMTP-AUTH methods if required by an SMTP relay server.
The SendMail Thread does not at this time support SMTP-TLS sessions.
The SendMail Thread currently can service one outgoing SMTP/ESMTP session at a time.
The mail server also services authenticated “post office” requests from mail clients using the POP3 protocol, by default, on TCP port 110.
The POP3 server supports client authentication via the USER or APOP methods.
The POP3 server can service multiple simultaneous incoming sessions.
For IMAP support, see Deuce's IMAP Service.
External Mail Processors