<?xml version="1.0"?>
<!DOCTYPE rfc SYSTEM "rfc2629.dtd">

<?rfc compact="no"?>
<?rfc toc="yes"?>
<?rfc private="The README file"?>
<?rfc header="README"?>

<rfc>
<front>
<title>The personal.tcl Mailbot</title>

<author initials="M.T." surname="Rose" fullname="Marshall T. Rose">
<organization>Dover Beach Consulting, Inc.</organization>
<address>
<postal>
<street>POB 255268</street>
<city>Sacramento</city> <region>CA</region> <code>95865-5268</code>
<country>US</country>
</postal>
<phone>+1 916 483 8878</phone>
<facsimile>+1 916 483 8848</facsimile>
<email>mrose@dbc.mtview.ca.us</email>
</address>
</author>

<date month="February" year="2002" />

<abstract><t>The personal.tcl mailbot implements a highly-specialized
filter for personal messages.
It MUST not be used by people who receive mailing list traffic in
their personal mailboxes.</t></abstract>
</front>

<middle>
<section title="SYNOPSIS">
<figure>
<preamble>Create a <xref target="configFile">configuration file</xref>
and add this line to your ".forward" file:</preamble>
<artwork><![CDATA[
    "| LIB/mbot-1.1/personal.tcl -config FILE -user USER"
]]></artwork>
<postamble>where "LIB" is where the Tcl library lives,
"FILE" is the name of your configuration file,
and "USER" is your username.</postamble>
</figure>

<section title="Requirements">
<t>This package requires:
<list style="symbols">
<t><eref target="http://core.tcl.tk/tcl/">Tcl version 8.3</eref>
or later</t>

<t><eref target="http://core.tcl.tk/tcllib/">tcl lib</eref></t>

<t><eref target="http://sourceforge.net/projects/tclx/">TclX version 8.0</eref>
or later</t>
</list></t>
</section>

<section title="Copyrights">
<t>(c) 1999-2002 Marshall T. Rose</t>

<t>Hold harmless the author, and any lawful use is allowed.</t>
</section>
</section>

<section title="PHILOSOPHY">
<t>The mailbot's philosophy is simple:
<list style="symbols">
<t>The mailbot receives all of your incoming personal mail.</t>

<t>You ALWAYS copy yourself on every message you send,
so that the mailbot receives all of your outgoing personal mail.</t>

<t>The mailbot performs six tasks, all optional:
<list>
<t>makes audit copies of your incoming and outgoing mail;</t>

<t>performs duplicate supression;</t>

<t>performs originator supression by rejecting messages from people
who aren't your friends or on a guest list;</t>

<t>performs content supression by rejecting messages that contain
attachments with extensions on your prohibited list;</t>

<t>sends a textual synopsis to your PDA; and,</t>

<t>sends a copy to your remote mailbox.</t>
</list></t>
</list></t>

<t>Do NOT use the personal.tcl mailbot if you receive mailing list
traffic in your personal mailbox.
When sending mail to a mailing list,
either:
<list style="symbols">
<t>use a "From" address that the personal.tcl mailbot will process as
"impersonal" mail,
(e.g., "hewes+ietf.general@example.com"); or,</t>

<t>set the "Reply-To" for the message to the mailing list.</t>
</list>
Consult <xref target="impersonal" /> for information on how
"impersonal" mail is identified and processed.</t>

<vspace blankLines="10000" />

<section title="Guest Lists">
<t>Guest lists are an effective mechanism for cutting back on
excessive mail.
<list style="symbols">
<t>when the mailbot receives a message from you,
it adds any recipients it finds to a permanent-guest list;</t>

<t>when the mailbot receives a message from someone on a guest list,
it adds any recipients it finds to a temporary-guest list; but,</t>

<t>when the mailbot receives a message from someone not on any guest
list,
they get a rejection notice.</t>
</list>
Note that in order to promote someone to the permanent-guest list,
you must send them a message (with a copy to yourself).
In most cases,
simply replying to the original message accomplishes this.
Of course,
if you don't want to promote someone to the permanent-guest list,
simply remove that address (or your address) from the list of
recipients in your reply.</t>

<t>Here are the fine points:
<list style="symbols">
<t>rejection notices contain a passphrase that may be used at most
once to bypass the guest list mechanism
(notices also contain the original message to minimize type-in
by the uninvited);</t>

<t>a flip-flop is used to avoid mail loops; and,</t>

<t>messages originated by an administrative address (e.g.,
"Postmaster") bypass the guest list mechanism
(unless the message refers to a previously-rejected message,
in which case it is supressed).</t>
</list></t>

<t>The rejection notice should be written carefully to minimize an
extreme negative reaction on the part of the uninvited.
Of course,
by allowing a passphrase,
this provides something of a CQ test for the uninvited --
if someone can't pass the test...</t>
</section>
</section>

<section title="BEHAVIOR">
<section title="Arguments">
<t>The mailbot supports the following command line arguments:
<list style="hanging">
<t hangText="   -config configFile:">
specifies the name of the configuration file to use;</t>

<t hangText="   -debug boolean:">
enables debug output;</t>

<t hangText="   -file messageFile:">
specifies the name of the file containing the message;</t>

<t hangText="   -originator orginatorAddress:">
specifies the email-address of the originator of the message; and,</t>

<t hangText="   -user userName:">
specifies the user-identity of the recipient.</t>
</list>
Note that if "-user" is given,
then the working directory is set to userName's home directory before
configFile is sourced,
and the umask is set defensively.</t>

<figure>
<preamble>The default values are:</preamble>
<artwork><![CDATA[
    personal.tcl -config     .personal-config.tcl   \
                 -debug      0                      \
                 -file       -                      \
                 -originator "derived from message"
]]></artwork>
<postamble>Given the default values,
only "-user" need be specified.
The reason is that if a message is being delivered to multiple local
recipients,
and if any of the ".forward" files are identical in content,
then sendmail may not deliver the message to all of the local
recipients.</postamble>
</figure>

<t>A few other (sendmail related) tips:
<list style="symbols">
<t>If sendmail is configured with smrsh,
you'll need to symlink personal.tcl into the
/usr/libexec/sm.bin/ directory.</t>

<t>Make sure that tclsh8.0 is in the path specified on the third-line
of personal.tcl.</t>

<t>You should chmod your ".forward" file to 0600.</t>
</list></t>
</section>

<vspace blankLines="10000" />

<section anchor="actions" title="Actions">
<t>The mailbot begins by parsing its arguments,
sourcing configFile,
and then examining the incoming message:
<list style="numbers">
<t>If <xref target="options.auditInFile">auditInFile</xref> is set,
a copy of the message is 
<xref target="procs.saveMessage">saved</xref> there.</t>

<t>If the message contains a previously-encountered "Message-ID",
processing terminates.</t>

<t>If the message's originator can not be determined,
a copy of the message is
<xref target="procs.saveMessage">saved</xref> in the
<xref target="options.defaultMaildrop">defaultMaildrop</xref> and
processing terminates.</t>

<t>The originator's email-address is examined:
<list>
<t>If the originator appears to be an
<xref target="procs.adminP">automated administrative process</xref>,
and if a previously rejected email-address is found in the message,
processing terminates.</t>

<t>Otherwise,
if the originator isn't <xref target="procs.ownerP">the user</xref>,
or <xref target="procs.friendP">a friend</xref>,
or a permanent-access guest,
or a temporary-access guest,
and if <xref target="options.noticeFile">noticeFile</xref> is set,
then the message is rejected.</t>

<t>Otherwise,
each recipient email-address in the message's header is added to a guest
list.
(If the originator is <xref target="procs.ownerP">the user</xref>,
the permanent-guest list is used instead of the temporary-guest
list.)</t>
</list></t>

<t>If the originator is the <xref target="procs.ownerP">the user</xref>,
then:
<list>
<t>If <xref target="options.auditOutFile">auditOutFile</xref> is set,
<xref target="procs.saveMessage">saved</xref> there.</t>

<t>Regardless, processing terminates.</t>
</list></t>

<t>If <xref target="options.pdaMailboxes">pdaMailboxes</xref> is set,
and if any plaintext is contained in the message,
then the plaintext is sent to those email-addresses.</t>

<t>If <xref target="options.remoteMailboxes">remoteMailboxes</xref> is set,
and if the message is successful resent to those email-addresses,
then processing terminates.</t>

<t>A copy of the message is
<xref target="procs.saveMessage">saved</xref> in the
<xref target="options.defaultMaildrop">defaultMaildrop</xref> and
processing terminates.</t>
</list></t>
</section>

<section anchor="configFile" title="The Configuration File">
<t>There are two kinds of information that may be defined in configFile:
<xref target="options">configuration options</xref> and
<xref target="procs">configurable procedures</xref>.</t>

<figure>
<preamble>Here's a simple example of a configFile for a user named
"example":</preamble>
<artwork><![CDATA[
    set options(dataDirectory)   .personal
    set options(defaultMaildrop) /var/mail/example
    set options(logFile)         [file join .personal personal.log]
    set options(noticeFile)      [file join .personal notice.txt]
]]></artwork>
</figure>

<section anchor="options" title="Configuration Options">
<t>configFile must define 
<xref target="options.dataDirectory">dataDirectory</xref>
and
<xref target="options.defaultMaildrop">defaultMaildrop</xref>.
All other configuration options are optional.</t>

<section anchor="options.dataDirectory" title="dataDirectory">
<t>The directory where the mailbot keeps its databases.
The subdirectories are:
<list style="hanging">
<t hangText="   badaddrs:">the directory of rejected email-addresses</t>

<t hangText="   inaddrs:">the directory of originator email-addresses</t>

<t hangText="   msgids:">the directory of Message-IDs</t>

<t hangText="   outaddrs:">the permanent-guest list</t>

<t hangText="   phrases:">the directory of at-most-once passphrases</t>

<t hangText="   tmpaddrs:">the temporary-guest list</t>
</list>
If you want to remove someone from a guest list,
simply go to that directory and delete the corresponding file.</t>
</section>

<section anchor="options.defaultMaildrop" title="defaultMaildrop">
<t>The filename where messages are 
<xref target="procs.saveMessage">saved</xref> for later viewing by
your user agent.</t>
</section>

<section anchor="options.auditInFile" title="auditInFile">
<t>The filename where messages are
<xref target="procs.saveMessage">saved</xref> for audit purposes.</t>
</section>

<section anchor="options.auditOutFile" title="auditOutFile">
<t>The filename where your outgoing messages are
<xref target="procs.saveMessage">saved</xref> for audit purposes.</t>
</section>

<section anchor="options.dropNames" title="dropNames">
<t>A list of filename extensions for attachments that automatically
cause the message to be rejected.</t>
</section>

<section anchor="options.friendlyDomains" title="friendlyDomains">
<t>A list used by <xref target="procs.friendP">friendP</xref> giving
the domain names where your friends live.</t>
</section>

<section anchor="options.friendlyfire" title="friendlyfire">
<t>If present and true,
then someone sending a message both to you and someone you've
previously sent mail to,
is considered a friend.</t>
</section>

<section anchor="options.logFile" title="logFile">
<t>The filename where the mailbot
<xref target="procs.tclLog">logs</xref> its actions.</t>
</section>

<section anchor="options.myMailbox" title="myMailbox">
<figure>
<preamble>Your preferred email-address with commentary text, e.g.,</preamble>
<artwork><![CDATA[
    Arlington Hewes <hewes@example.com>
]]></artwork>
</figure>
</section>

<section anchor="options.noticeFile" title="noticeFile">
<t>The filename containing the textual notice sent when a message is
rejected.
Note that all occurrances of "%passPhrase%" within this file are
replaced with an at-most-once passphrase allowing the originator to
bypass the mailbot's filtering.
Similarly,
any occurrences of "%subject%" are replaced by the "Subject" of the
incoming message.</t>
</section>

<section anchor="options.pdaMailboxes" title="pdaMailboxes">
<t>The email-addresses where a textual synopsis of the incoming message is
sent.</t> 
</section>

<section anchor="options.remoteMailboxes" title="remoteMailboxes">
<t>The email-addresses where a copy of the incoming message is resent.</t> 
</section>
</section>

<vspace blankLines="10000" />

<section anchor="procs" title="Configurable Procedures">
<t>All of these procedures are defined in personal.tcl.
You may override any of them in configFile.</t>

<section anchor="procs.adminP" title="adminP">
<figure>
<artwork><![CDATA[
    proc adminP {local domain}
]]></artwork>
</figure>

<t>Returns "1" if the email-address is an automated administrative
process.</t>
</section>

<section anchor="procs.friendP" title="friendP">
<figure>
<artwork><![CDATA[
    proc friendP {local domain}
]]></artwork>
</figure>

<t>Returns "1" if the email-address is from a
<xref target="options.friendlyDomains">friendly domain</xref> or
sub-domain.</t>
</section>

<section anchor="procs.ownerP" title="ownerP">
<figure>
<artwork><![CDATA[
    proc ownerP {local domain}
]]></artwork>
</figure>

<t>Returns "1" if the email-address refers to the user
(as determined by looking at
<xref target="options.myMailbox">myMailbox</xref>,
<xref target="options.pdaMailboxes">pdaMailboxes</xref>, and
<xref target="options.remoteMailboxes">remoteMailboxes</xref>.</t>
</section>

<section anchor="procs.saveMessage" title="saveMessage">
<figure>
<artwork><![CDATA[
    proc saveMessage {inF {outF ""}}
]]></artwork>
</figure>

<t>Saves a copy of the message contained in the file inF.
If the destination file,
outF,
isn't specified,
it defaults to the
<xref target="options.defaultMaildrop">defaultMaildrop</xref>.</t> 
</section>

<section anchor="procs.findPhrase" title="findPhrase">
<figure>
<artwork><![CDATA[
    proc findPhrase {subject}
]]></artwork>
</figure>

<t>Returns "1" if a previously-allocated passphrase is present in the
subject.
If so,
the passphrase is forgotten.</t>
</section>

<section anchor="procs.makePhrase" title="makePhrase">
<figure>
<artwork><![CDATA[
    proc makePhrase {}
]]></artwork>
</figure>

<t>Returns an at-most-once passphrase for use with a rejection notice.</t>
</section>

<section anchor="procs.pruneDir" title="pruneDir">
<figure>
<artwork><![CDATA[
    proc pruneDir {dir type}
]]></artwork>
</figure>

<t>Removes old entries from one of the mailbot's 
<xref target="options.dataDirectory">databases</xref>.
The second parameter is one of "addr", "msgid", or "phrase".</t>
</section>

<section anchor="procs.tclLog" title="tclLog">
<figure>
<artwork><![CDATA[
    proc tclLog {message}
]]></artwork>
</figure>

<t>Writes a message to the <xref target="options.logFile">logFile</xref>.</t>
</section>
</section>
</section>

</section>

</middle>

<back>
<references />

<section anchor="impersonal" title="Impersonal Mail">
<t>If <xref target="procs.impersonalMail">impersonalMail</xref>
returns a non-empty string
then the message is processed differently than the algorithm given in
<xref target="actions" />.
Specifically:
<list style="numbers">
<t>If the message contains a previously-encountered "Message-ID",
processing terminates.</t>

<t>If the message's originator can not be determined,
processing terminates.</t>

<t>The value returned by
<xref target="procs.impersonalMail">impersonalMail</xref>
is the folder's name and is broken into one or more components
seperated by dots (".").
If there aren't at least two components,
or if any of the components are empty
(e.g., the folder is named "sys..announce"),
then the message is bounced.</t>

<t>If <xref target="options.mappingFile">mappingFile</xref> exists,
that file is examined to see if an entry is present for the folder.
If so,
the message is processed according to the value present,
one of:
<list style="hanging">
<t hangText='     "ignore":'>the message is silently ignored;</t>

<t hangText='     "bounce":'>the message is noisily bounced; or,</t>

<t hangText="    otherwise:">the message is resent to the address.</t>
</list>
Regardless,
if an entry was present for the folder,
then processing terminates.</t>

<t>The message is <xref target="procs.saveMessage">saved</xref> 
in a file whose name is constructed by replacing each dot (".") in the
folder name with a directory seperator
(e.g., if the folder is named "sys.announce",
then the file is called "announce" underneath the directory "sys"
underneath the directory identified by
<xref target="options.foldersDirectory">foldersDirectory</xref>.</t>

<t>Finally,
the file identified by <xref target="options.foldersFile">foldersFile</xref>
is updated as necessary.</t>
</list></t>

<vspace blankLines="10000" />

<section anchor="impersonal.options" title="Configuration Options">
<t>If "impersonal" mail is received,
then <xref target="options.foldersFile">foldersFile</xref> and
<xref target="options.foldersDirectory">foldersDirectory</xref> 
must exist.</t>

<section anchor="options.foldersDirectory" title="foldersDirectory">
<t>The directory where the mailbot keeps private folders.</t>
</section>

<section anchor="options.foldersFile" title="foldersFile">
<t>This file contains one line for each private folder.</t>
</section>

<section anchor="options.announceMailboxes" title="announceMailboxes">
<t>The email-addresses where an announcement is sent when a new
private folder is created.</t>
</section>

<section anchor="options.mappingFile" title="mappingFile">
<t>The file consulted by the mailbot to determine how to process
"impersonal" messages.
Each line of the file consists of a folder name and value,
seperated by a colon (":").
There are three reserved values: "bounce", "ignore", and "store".</t>
</section>
</section>

<vspace blankLines="10000" />

<section anchor="impersonal.procs" title="Configurable Procedures">
<t>All of these procedures are defined in personal.tcl.
You may override any of them in configFile.</t>

<section anchor="procs.impersonalMail" title="impersonalMail">
<figure>
<artwork><![CDATA[
    proc impersonalMail {}
]]></artwork>
</figure>

<t>If the message is deemed "impersonal",
return the name of a corresponding private folder;
otherwise,
return the empty-string.</t>

<t>Many mail systems have a mechanism of passing additional
information when performing final delivery using a program.
With modern versions of sendmail,
for example,
if mail is sent to a local user named "user+detail",
then,
in the absense of an alias for either "user+detail" or "user+*",
then the message is delivered to "user".
The trick is to get sendmail to pass the "detail" part to the mailbot.</t>

<figure>
<preamble>At present,
sendmail passes this information only if procmail is your local
mailer.
Here's how I do it:</preamble>
<artwork><![CDATA[
    *** _alias.c    Tue Dec 29 10:42:25 1998
    --- alias.c     Sat Sep 18 21:51:35 1999
    ***************
    *** 813,818 ****
    --- 813,821 ----
            define('z', user->q_home, e);
            define('u', user->q_user, e);
            define('h', user->q_host, e);
    + 
    +       setuserenv("SUFFIX", user->q_host);
    + 
            if (ForwardPath == NULL)
                    ForwardPath = newstr("\201z/.forward");
]]></artwork>
<postamble>This makes available an environment variable called
"SUFFIX" which has the "details" part.
The drawback in this approach is that this information is lost if the
message is re-queued for delivery
(what's really needed is an addition to the .forward syntax to allow
macros such as $h to be passed).</postamble>
</figure>

<figure>
<preamble>The corresponding impersonalMail procedure is defined as:</preamble>
<artwork><![CDATA[
    proc impersonalMail {} {
        global env

        return $env(SUFFIX)
    }
]]></artwork>
</figure>
</section>

<section anchor="procs.processFolder" title="processFolder">
<figure>
<artwork><![CDATA[
    proc processFolder {folderName mimeT} { return $string }
]]></artwork>
</figure>

<t>If an entry for the folder exists in the
<xref target="options.mappingFile">mappingFile</xref>,
and if the value for that entry is "process",
then this procedure is invoked to return a string indicating what
action to take
(cf., <xref target="impersonal" />).</t>
</section>
</section>
</section>

<section title="An Example configFile">
<figure>
<preamble>Here is the ".forward" file for the user "hewes":</preamble>
<artwork><![CDATA[
    "|/usr/pkg/lib/mbot-1.1/personal.tcl 
         -config .personal/config.tcl -user hewes"
]]></artwork>
<postamble>(Of course, it's all on one line.)</postamble>
</figure>

<figure>
<preamble>Here is the user's ".personal/config.tcl" file:</preamble>
<artwork><![CDATA[
    array set options [list                                          \
        dataDirectory     .personal                                  \
        defaultMaildrop   /var/mail/hewes                            \
        auditInFile       [file join .personal INCOMING]             \
        auditOutFile      [file join .personal OUTGOING]             \
        friendlyDomains   [list tcp.int example.com]                 \
        logFile           [file join .personal personal.log]         \
        myMailbox         "Arlington Hewes <hewes@example.com>"      \
        pdaMailboxes      hewes.pager@example.com                    \
        noticeFile        [file join .personal notice.txt]           \
        foldersDirectory  [file join .personal folders]              \
        foldersFile       [file join .personal .mailboxlist]         \
        announceMailboxes hewes+sys.announce@example.com             \
        mappingFile       [file join .personal mapping]              \
        friendlyFire      1                                          \
        dropNames         [list *.bat *.exe *.src *.pif *.wav *.vbs] \
    ]

    proc impersonalMail {} {
        global env

        return $env(SUFFIX)
    }
]]></artwork>
<postamble>Note that because
<xref target="options.remoteMailboxes">remoteMailboxes</xref> isn't
defined,
personal messages are ultimately stored in the user's
<xref target="options.defaultMaildrop">defaultMaildrop</xref>.</postamble>
</figure>
</section>

<section title="Acknowledgements">
<t>The original version of this mailbot was written by the author in 1994,
implemented using  the safe-tcl package
(Borenstein and Rose, circa 1993).</t>
</section>

</back>

</rfc>
