Mail::DKIM::ARC::Seal(3) User Contributed Perl Documentation NAME Mail::DKIM::ARC::Seal - represents a ARC-Seal header VERSION version 1.20230911 CONSTRUCTORS new() - create a new signature from parameters my $signature = Mail::DKIM::ARC::Seal->new( [ Algorithm => 'rsa-sha256', ] [ Signature => $base64, ] [ Domain => 'example.org', ] [ Instance => 1, ] [ Chain => 'none', ] # none|fail|pass [ Query => 'dns', ] [ Selector => 'alpha', ] [ Timestamp => time(), ] [ Expiration => time() + 86400, ] ); The ARC-Seal is similar to a DKIM signature but with the following changes: https://tools.ietf.org/html/draft-ietf-dmarc-arc-protocol-06 5.1.1.1. Tags in the ARC-Seal Header Field Value The following tags are the only supported tags for an ARC-Seal field. All of them MUST be present. Unknown tags MUST be ignored and do not affect the validity of the header. o a = hash algorithm; syntax is the same as the "a=" tag defined in Section 3.5 of [RFC6376]; o b = digital signature; syntax is the same as the "b=" tag defined in Section 3.5 of [RFC6376]; o cv = chain validation status: valid values: * 'none' = no pre-existing chain; * 'fail' = the chain as received does not or can not validate; or * 'pass' = valid chain received. o d = domain for key; syntax is the same as the "d=" tag defined in Section 3.5 of [RFC6376]; o i = "instance" or sequence number; monotonically increasing at each "sealing" entity, beginning with '1', see Section 5.1.1.1.1 regarding the valid range o s = selector for key; syntax is the same as the "s=" tag defined in Section 3.5 of [RFC6376]; o t = timestamp; syntax is the same as the "t=" tag defined in Section 3.5 of [RFC6376]. chain() - get or set the chain parameter (cv=) field This must be one of "pass", "fail" or "none". For a chain to be valid, the very first (i=1) seal MUST be cv=none, and all further seals MUST be cv=pass. instance() - get or set the signing instance (i=) field my $i = $signature->instance; Instances must be integers less than 1024 according to the spec. SEE ALSO Mail::DKIM::Signature for DKIM-Signature headers Mail::DKIM::ARC::MessageSignature for ARC-Message-Signature headers AUTHORS o Jason Long o Marc Bradshaw o Bron Gondwana (ARC) THANKS Work on ensuring that this module passes the ARC test suite was generously sponsored by Valimail (https://www.valimail.com/) COPYRIGHT AND LICENSE o Copyright (C) 2013 by Messiah College o Copyright (C) 2010 by Jason Long o Copyright (C) 2017 by Standcore LLC o Copyright (C) 2020 by FastMail Pty Ltd This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.6 or, at your option, any later version of Perl 5 you may have available. perl v5.38.0 2023-10-09 Mail::DKIM::ARC::Seal(3)