Approver is a set of Perl and Bourne shell scripts that adds the following capabilities to a moderated Majordomo mailing list:

• Pre-approves messages posted from e-mail accounts listed in the list.approved ACL file, while preserving Majordomo approval semantics for posts made by people not found in the ACL file.
• Rejects attempted posts from e-mail accounts not subscribed to a mailing list. This helps prevent bogus SPAM and virus posts from being bounced to moderators when Approver is installed.
• Passes all posts through DEMIME to convert all HTML posts to plain text before Majordomo even sees the post.
• Automatically adds that mandatory newline after the approved: password as required by Majordomo.

• Everything you need in one tarball
• rmmime
• approved
• list_example.cf

The following 3 commands must be installed in the Majordomo root directory:

• approved
• rmmime
• demime

Approver consists of two scripts: the Bourne shell script rmmime and the Perl script approved. rmmime is installed as a sendmail alias, and is a direct replacement for the Majordomo resend command. Here is an example sendmail aliases entry using rmmime:

test-list: "|/etc/smrsh/wrapper rmmime '-l test-list -h yourdomain.org test-list-outgoing'"

Note: If you already have DEMIME installed and configured in your environment, you may want to disable the --noadremove option in rmmime. Simply edit rmmime and comment out the ADREMOVE= line.

To enable the mailing list pre-approval, you must create two configuration files:

• list-example.cf
• list-example.approved

list-example.cf contains the mailing list approval password. Here is an example list-example.cf file:

#
# Example mailing list configuration file. Now there is only
# one configuration variable recognized: APPROVED_STRING.
# This parameter sets the string inserted into the the first
# line of the body of mail messages for Majordomo moderated 
# list auto approval.
#
$APPROVED_STRING = "approved: password\n\n";

Replace password with the actual password for your mailing list. Do not disturb the syntax of the rest of this line. This is interpreted as a Perl assignment statement, and you could introduce a syntax error unless you are careful.

list-example.approved contains the e-mail addresses of people allowed to post directly to the moderated list without Moderator intervention. List a single e-mail address per line. No blank lines or comments are allowed in this file.

Approver assumes your Majordomo installation is located in /usr/majordomo, and your mailing lists are configured under /usr/majordomo/lists. If this is not the case, you can either install a /usr/majordomo symbolic link pointing to your Majordomo root directory, or directly modify the approved script. Note: If your mailing lists are not configured under $MAJORDOMO/lists, you must directly modify the approved script.

• approved - The main implementation of Approver.
• rmmime - Script added to sendmail /etc/aliases to invoke approved
• demime - Perl script called by rmmime ahead of approved to strip all HTML content from e-mail before passed to Majordomo.
• list.cf - Mailing list configuration file containing the approved password for that mailing list. Each mailing list has such a configuration file.
• list.approved - Mailing list configuration file containing the list of e-mail addresses of people pre-approved to post to the moderated mailing list. Each mailing list has such a configuration file.
• approved_denied.log - File logging all attempted posts bounced by Approver. The list posted to, the address posted from and the date and time of the post are logged.

• Someone capable of forging the From: line in an e-mail and possessing knowledge of an Approver registered e-mail address for the mailing list in question is now able to post to that moderated list. While technically trivial to accomplish, no e-mail worm or virus seems to have yet to put these two data together. As this project was originally conceived to reduce the number of bounced messages sent to moderators from list subscribers with infected computers, this goal has been achieved without unauthorized posts occurring, although they can happen.
• Messages previously bounced to moderators by unsubscribed list members are now completely masked, although all such attempted posts are logged to $MAJORDOMO/approved_denied.log. Perhaps Approver should send a message to the original poster inviting them to join the list first, then repost their message. Their message will still bounce, but the moderator will now receive a bounce notification from Majordomo.

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    * Neither the name of Adam Bernstein nor the names of its
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