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makesmtpaccess(8)


NAME

   makesmtpaccess - Build ESMTP server access file

SYNOPSIS

   makesmtpaccess

   makesmtpaccess-msa

DESCRIPTION

   makesmtpaccess rebuilds the contents of the /etc/courier/smtpaccess.dat
   database from the contents of the files in the /etc/courier/smtpaccess
   directory. When the esmtpd script starts couriertcpd, the script
   specifies /etc/courier/smtpaccess.dat file to control access to the
   Courier mail server's ESMTP daemon. The makesmtpaccess script must be
   run before any changes in the /etc/courier/smtpaccess directory take
   effect.  Note that this build of courier ignores any files that match
   the regex pattern ".*.dpkg-[a-z]*" (dpkg configuration file handling)
   and ".*~" (backup files of some editors).

   The couriertcpd(8)[1] manual page describes the general format of
   access files.

   The default Courier mail server configuration uses the same access
   file, /etc/courier/smtpaccess.dat for both the regular ESMTP server,
   and the message submission server on port 587 (RFC 2476[2]). It is
   possible to use different access files. To do so, create a different
   access file, edit /etc/courier/esmtpd-msa, and set ACCESSFILE to the
   filename of the access file directory (the directory containing the
   plain text files, not the .dat file). Then, use makesmtpaccess-msa
   instead of makesmtpaccess to build the .dat file.

   The smtpaccess configuration file
   The couriertcpd(8)[1] manual page describes the generic format of the
   access file. The access file specifies what should be done with
   connections from defined IP address ranges. The basic choices are to
   accept or reject the connection. Also, the generic format of the access
   file allows arbitrary environment variables to be set based on the
   connection's remote IP address.

   The Courier mail server's ESMTPD server understands the following
   environment variables, which may be set in the access file:

   BLOCK
       If this variable is set to a non-empty value, all mail will be
       rejected for this connection. The contents of the environment
       variable will be used as the error message. This is not the same as
       the couriertcpd access file setting that immediately drops the
       connection. The incoming connection is accepted, but every message
       will be rejected.

   FAXRELAYCLIENT
       Allow the client to send faxes via the courierfax(8)[3] module.

           Note
           When ESMTP authentication is enabled, a successful
           authentication automatically sets FAXRELAYCLIENT.

   RELAYCLIENT
       Allow the client to relay mail.

           Note
           When ESMTP authentication is enabled, a successful
           authentication automatically sets RELAYCLIENT.

   The following options are typically set globally in the esmtpd
   configuration file, but may be overriden in the smtpaccess
   configuration file:

   BOFHCHECKDNS
       Do not check the return address's domain in DNS if this environment
       variable is set to 0. The default value of BOFHCHECKDNS is 1.

           Note
           Turning off the DNS check disables a number of options in the
           bofh configuration file. See courier(8)[4] for more
           information.

   BOFHCHECKHELO
       Set this variable to 1 to check the hostname argument to the ESMTP
       HELO/EHLO command, as follows:

       *   A hostname that's actually an IP address, and is the same as
           the connecting ESMTP client's IP address, is valid.

       *   Otherwise hostname should be a valid DNS name with MX and/or A
           records, with at least one record matching the connecting ESMTP
           client's IP address.

       *   An ESMTP client with relaying privileges (either due to
           RELAYCLIENT explicitly set, or if it succesfully authenticates)
           may use anything for an EHLO/HELO. The EHLO/HELO argument
           coming from an authenticated/relaying client is not checked.

   BOFHNOEXPN
       Disable the EXPN command if this environment variable is set to 1.

   BOFHNOVRFY
       Disable the VRFY command if this environment variable is set to 1.

   Other useful environment variables are listed in the submit(8)[5]
   manual page.

SEE ALSO

   esmtpd(8)[6], couriertcpd(8)[1], submit(8)[5].

AUTHOR

   Sam Varshavchik
       Author

NOTES

    1. couriertcpd(8)
       [set $man.base.url.for.relative.links]/couriertcpd.html

    2. RFC 2476
       http://www.rfc-editor.org/rfc/rfc2476.txt

    3. courierfax(8)
       [set $man.base.url.for.relative.links]/courierfax.html

    4. courier(8)
       [set $man.base.url.for.relative.links]/courier.html

    5. submit(8)
       [set $man.base.url.for.relative.links]/submit.html

    6. esmtpd(8)
       [set $man.base.url.for.relative.links]/esmtpd.html



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