'\" t .\" Title: vrfydmn .\" Author: [see the "AUTHOR" section] .\" Generator: DocBook XSL Stylesheets v1.78.1 .\" Date: 02/09/2015 .\" Manual: vrfydmn Manual .\" Source: vrfydmn 0.4 .\" Language: English .\" .TH "VRFYDMN" "8" "02/09/2015" "vrfydmn 0\&.4" "vrfydmn Manual" .\" ----------------------------------------------------------------- .\" * Define some portability stuff .\" ----------------------------------------------------------------- .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .\" http://bugs.debian.org/507673 .\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" ----------------------------------------------------------------- .\" * set default formatting .\" ----------------------------------------------------------------- .\" disable hyphenation .nh .\" disable justification (adjust text to left margin only) .ad l .\" ----------------------------------------------------------------- .\" * MAIN CONTENT STARTS HERE * .\" ----------------------------------------------------------------- .SH "NAME" vrfydmn \- reject an email message if the RFC5322 From:\-address does not comply\&. .SH "SYNOPSIS" .sp \fBvrfydmn\fR [\fIOPTIONS\fR] \fIFILE\fR .SH "DESCRIPTION" .sp In email everyone is free to specify any RFC5322 From:\-header address\&. Miscreants \(em virus authors, spammers and phishers \(em are aware of this fact\&. They forge the RFC5322 From:\-header address on purpose to impersonate someone that suits their goal\&. .sp Average users are not aware of this fact\&. They tend to believe a message really was sent by the person indicated in the RFC5322 From:\-header address\&. .sp vrfydmn verifies RFC5322 From:\-headers in mail messages\&. It compares a messages From:\-header field to a list of permitted sender domains assigned to the sender\&. If the address does not meet the expectations vrfydmn may either rectify the RFC5322 From:\-header or reject the message\&. .sp This program was created to control and reject phishing abuse on SMTP submission ports\&. It serves also to prevent mail loss in cases, when the given address was under DMARC policy, i\&.e\&. Yahoo or AOL\&. .SH "OPTIONS" .PP \fB\-u, \-\-user\fR \fIuser\fR (default: \fImilter\fR) .RS 4 Run vrfydmn as user \fIuser\fR\&. .RE .PP \fB\-g, \-\-group\fR \fIgroup\fR (default: \fImilter\fR) .RS 4 Run vrfydmn as group \fIuser\fR\&. .RE .PP \fB\-s, \-\-socket\fR \fIsocket\fR (default: \fIinet6:30072@[::1]\fR) .RS 4 Specifes the socket vrfydmn should listen on for incoming verification requests\&. The socket consists of three parts \- \fIprotocol\fR, \fIport\fR and \fIaddress\fR\&. .RE .PP \fIprotocol\fR .RS 4 Use \fIinet\fR as prefix to indicate an IPv4 socket e\&.g\&. \fIinet:10000@127\&.0\&.0\&.1\fR or \fIinet6\fR as prefix to indicate an IPv6 socket e\&.g\&. \fIinet6:30072@[::1]\fR\&. .RE .PP \fIport\fR .RS 4 Use numbers to indicate the port vrfydmn should establish its socket on e\&.g\&. \fI30072\fR\&. .RE .PP \fIaddress\fR .RS 4 Specify an IP address\&. The address type must correspond to the \fIprotocol\fR choosen\&. IPv6 addresses must be enclosed in square brackets e\&.g\&. \fI[address]\fR\&. .RE .PP \fB\-p, \-\-pid\fR \fIpidfile\fR (default: none) .RS 4 Specifies the name of a file in which vrfydmn should note its process id\&. .RE .PP \fB\-f, \-\-file\fR \fIfile\fR (default: none) .RS 4 This file typically is a postfix(8) map, i\&.e\&. relay_domains file\&. It should be a map with 2 columns\&. First column is the domain (the key) and the second column represents some value\&. The value is totally ignored in vrfydmn! If a flat file was given, the file can be refreshed during runtime by sending the SIGHUP signal and the result can be dumped to syslog (or standard out, if \-d, \-\-debug was given) with the SIGUSR1 signal\&. .RE .PP \fB\-l, \-\-ldap\fR \fIfile\fR (default: none) .RS 4 Specifies the path to a configuration file\&. The file holds options for LDAP queries\&. If specified vrfydmn will establish a persistent LDAP connection\&. See vrfydmn_ldap(5) for details\&. .RE .PP \fB\-m, \-\-memcached\fR \fIsocket\fR (default: none) .RS 4 Specifies a TCP socket to a memcache server\&. If enabled LDAP query results will be cached in the memcache\&. The socket must be specified as \fIaddress\fR and \fIport\fR separated by a colon e\&.g\&. \fI127\&.0\&.0\&.1:11211\fR\&. .RE .PP \fB\-f, \-\-fix\fR .RS 4 If specified vrfydmn will not reject messages with RFC5322 From:\-headers that fail verification\&. Instead it will attempt to fix them\&. It will copy the erroneous header to a Reply\-To:\-header (only if none already exists)\&. Then it will replace the existing From:\-header with the envelope\-sender address (MAIL From)\&. This option is recommended for web servers\&. .RE .PP \fB\-d, \-\-debug\fR .RS 4 This option is mainly for debugging and development purposes\&. If specified vrfydmn will not detach\&. It will run in foreground and output its activities to stdout\&. .RE .SH "SEE ALSO" .sp vrfydmn_ldap(5) .SH "BUGS" .sp There are no known bugs so far\&. Please submit bugs to https://github\&.com/croessner/vrfydmn/issues\&. .SH "AUTHOR" .sp Christian Roessner wrote the program\&. .sp Patrick Ben Koetter wrote this man page\&. .SH "RESOURCES" .sp vrfydmn\(cqs home is at https://github\&.com/croessner/vrfydmn\&. .SH "COPYING" .sp Copyright (C) 2014\-2015 Christian Roessner\&. Free use of this software is granted under the terms of the GNU General Public License (GPL)\&.