1 .\"	$OpenBSD$
2 .\"
3 .\" Copyright (c) 2024 Kirill A. Korinsky <kirill@korins.ky>>
4 .\" Copyright (c) 2019 Martijn van Duren <martijn@openbsd.org>
5 .\"
6 .\" Permission to use, copy, modify, and distribute this software for any
7 .\" purpose with or without fee is hereby granted, provided that the above
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14 .\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
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18 .Dd $Mdocdate$
19 .Dt FILTER-AUTH 8
20 .Os
21 .Sh NAME
22 .Nm filter-auth
23 .Nd authenticate email and add Authentication-Results header
24 .Sh SYNOPSIS
25 .Nm
26 .Op Fl A
27 .Op Ar authserv-id
28 .Sh DESCRIPTION
29 .Nm
30 verifies the DKIM and ARC signatures of messages, the SPF policy and
31 adds an Authentication-Results header to the message. If the
32 .Fl A
33 flag is specified, it adds the ARC-Authentication-Results header
34 instead, with the next unused
35 .Em i
36 value in the chain. This filter gets used
37 .Em authserv-id
38 from OpenSMTPD which can be overridden by the
39 .Ar authserv-id
40 argument.
41 .Sh SEE ALSO
42 .Xr filter-admdscrub 8
43 .Xr filter-dkimsign 8
44 .Xr smtpd 8
45 .Sh STANDARDS
46 .\" RFC7208
47 .\" RFC8601
48 .Rs
49 .%A J. Klensin
50 .%D October 2008
51 .%R RFC 5321
52 .%T Simple Mail Transfer Protocol
53 .Re
54 .Pp
55 .Rs
56 .%A D. Crocker, Ed.
57 .%Q Brandenburg InternetWorking
58 .%A T. Hansen, Ed.
59 .%Q AT&T Laboratories
60 .%A M. Kucherawy, Ed.
61 .%Q Cloudmark
62 .%D September 2011
63 .%R RFC 6376
64 .%T DomainKeys Identified Mail (DKIM) Signatures
65 .Re
66 .Pp
67 .Rs
68 .%A S. Kitterman
69 .%Q Kitterman Technical Services
70 .%D April 2014
71 .%R RFC 7208
72 .%T Sender Policy Framework (SPF) for Authorizing Use of Domains in Email, Version 1
73 .Re
74 .Pp
75 .Rs
76 .%A M. Kucherawy
77 .%D May 2019
78 .%R RFC 8601
79 .%T Message Header Field for Indicating Message Authentication Status
80 .Re
81 .Sh AUTHORS
82 .An Kirill A. Korinsky Aq Mt kirill@korins.ky
83 .An Martijn van Duren Aq Mt martijn@openbsd.org
84 .An Gilles Chehade Aq Mt gilles@poolp.org