receivedmsgiddb(1)

NAME

receivedMSGIDdb - validate the "Message-ID: " records in

the headers of e-mail files against domain names in a database

file

SYNOPSIS

receivedMSGIDdb [-c] [-f from_address] [-r m|n]  [-v]  dbfilename [filename(s)]

DESCRIPTION

ReceivedMSGIDdb is for validating the "Message-ID: "

records in the headers of e-mail files against domain names in a

database file.

The program requires a Posix compatible regex(3) library

to parse the e-mail addresses, and mmap(2) to map the database

file of e-mail addresses into the Unix VM system. The e-mail ad

dresses from the e-mail header are validated against the database

file using a binary search. The database file name is a required

command line argument.

The database is a standard Unix text file, one e-mail ad

dress per line, in lexical order, constructed with "sort -u in

file > outfile", or equivalent.

The database mechanism is conservative with machine re

sources, requiring about 12.5 micro-seconds of machine time to

lookup a word in the Unix system dictionary, (2.5 MB, quarter of

a million words, single 466 MHz., Pentium, lightly loaded, Linux

2.2, time(1) command to lookup every word in the dictionary, di

vided by the number of words.) Conceptually, the database mecha

nism is implemented similar to the the technique used in the

look(1) command, but requires exact matches, as opposed to par

tial key matches.

The input e-mail file name(s) may be supplied as addition

al optional command line arguments, or redirected to the program

via stdin for compatibility with procmail(1), and other e-mail

scripting agents.

A suitable procmail(1) recipe example might be:

:0 wfh
* ? receivedMSGIDdb address.db
| formail -A "X-Notice: Message in address.db

database"

The -f from_address option can be used to validate that

the "Message-ID: " and the "From: " e-mail address, (or any other

e-mail address,) are from the same machine/domain. The -f option

can be used multiple times to validate any number e-mail address

es.

The program contains less than 300 lines of declarations

and statements, all of which are documented with in line com

ments.

The program has been compiled and tested on SunOS, So

laris, and Linux, and may work on other brands of Unix.

The program returns 0 if no error and a match was found in

the database file for the domain name in any "Message-ID: " head

er records, 1 if no error and no match found; else returns a

unique error code greater than 1 representing the error encoun

tered-which will, also, print an error diagnostic to stderr.

However, if one or more e-mail addresses are specified on

the command line with the -f option, then if all e-mail addresses

have the same domain name as found in the database file from the

"Message-ID: " header record, then the program returns 1. If any

e-mail address does not have the same domain name as found in the

database file from the "Message-ID: " record, then the program

returns 0. If the domain name in the "Message-ID: " record is not

found in the database, the program returns 1, as before. The re

turn values for the -f option are for compatibility with procmail

scripts.

The -r option is useful for controlling the return value

under error conditions-for example, the program return can be

preempted if the database file can not be opened, (or read,) with

a return value of match, or no match, depending on environmental

requirements.

OPTIONS

dbfilename

Database file name.

filename(s)

E-mail file name(s), (defaults to stdin).

-c Print all matching e-mail addresses, not just the

first.

-f from_address

Validate the e-mail address, from_address.

-r m|n On file error, exit return = match for m, no match

for n.

-v Print the program's version information.

WARNINGS

Under buffer overflow conditions, the program makes no at

tempts at handling the situation-it just detects it, prints an

error message, and exits.

SEE ALSO

receivedIP(1), receivedIPdb(1), receivedIPdbdedup(1), re

ceivedIPdbrm(1), receivedIPdbusort(1), bsearchtext(1), re

ceivedAddress(1), receivedTodb(1), receivedMSGIDdb(1), receive

dUnknowndb(1), tolower(1), toupper(1), bsorttext(1) receivedIP

forgedb(1), hsearchtext(1), bsearchbody(1)

DIAGNOSTICS

Error messages for incompatible arguments, failure to al

locate memory, inaccessible files, opening and closing files, in

put record buffer overflow, compiling regular expressions, and e

mail header format or structure errors.

AUTHORS

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A license is hereby granted to reproduce this software

source code and
to create executable versions from this source code for

personal,
non-commercial use. The copyright notice included with

the software
must be maintained in all copies produced.

THIS PROGRAM IS PROVIDED "AS IS". THE AUTHOR PROVIDES NO

WARRANTIES
WHATSOEVER, EXPRESSED OR IMPLIED, INCLUDING WARRANTIES OF
MERCHANTABILITY, TITLE, OR FITNESS FOR ANY PARTICULAR PUR

POSE. THE
AUTHOR DOES NOT WARRANT THAT USE OF THIS PROGRAM DOES NOT

INFRINGE THE
INTELLECTUAL PROPERTY RIGHTS OF ANY THIRD PARTY IN ANY

COUNTRY.

Copyright (c) 2001-2007, John Conover, All Rights Re

served.

Comments and/or bug reports should be addressed to:

john@email.johncon.com (John Conover)

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January 16, 2007 RE

CEIVEDMSGIDDB(1)