NAME

Mail::MIMEDefang::BIMI - Brand Indicators for Message Identification support for MIMEDefang

DESCRIPTION

Mail::MIMEDefang::BIMI provides methods to look up and verify BIMI DNS records from mimedefang-filter. BIMI (Brand Indicators for Message Identification) allows domain owners to publish a verified logo that mail clients can display alongside authenticated messages.

A BIMI record is only considered valid when the sending domain passes DMARC at enforcement level (p=quarantine or p=reject).

When the Mail::BIMI Perl module (version 3.x or later) is installed, md_bimi_lookup and md_bimi_verify use it for richer validation, including SVG logo integrity and Verified Mark Certificate (VMC) chain verification. Without Mail::BIMI the checks are limited to DNS record existence and a non-empty l= tag.

METHODS

md_init

Detect and load Mail::BIMI if installed, setting $Features{"Mail::BIMI"}. Called automatically by detect_and_load_perl_modules in Mail::MIMEDefang.

md_bimi_get_selector($entity)

Extract the BIMI selector from the BIMI-Selector header of a MIME::Entity object. The header format is:

BIMI-Selector: v=BIMI1; s=brand1;

Returns the selector string (e.g. "brand1") on success, or "default" when the header is absent, malformed, or $entity is undefined.

Typical usage in filter_begin($entity):

my $selector = md_bimi_get_selector($entity);
my $result   = md_bimi_verify($domain, $dmarc_result, $policy, $selector);

md_bimi_lookup($domain [, $selector])

Look up the BIMI DNS TXT record for $domain.

The optional $selector argument specifies which BIMI selector to query (e.g. "brand1" → brand1._bimi.$domain). When omitted or undef, "default" is used. Use md_bimi_get_selector to derive the selector from the message's BIMI-Selector header.

Returns a hashref with the following keys on success:

version

Always BIMI1.

l

The URL of the SVG logo (l= tag).

a

The URL of the Verified Mark Certificate (a= tag), if present.

raw

The raw TXT record string.

Returns undef if no BIMI record is found or if Net::DNS is not available.

md_bimi_verify($domain, $dmarc_result, $dmarc_policy [, $selector])

Verify that a domain's BIMI record is valid given the DMARC result.

BIMI is only considered to pass when:

• A BIMI DNS record exists for $domain.

• $dmarc_result is pass.

• $dmarc_policy is quarantine or reject (enforcement level).

• The BIMI record contains a non-empty l= (logo URL) tag.

Returns "pass" on success, "fail" otherwise.

The method accepts the following parameters:

$domain

The sender's domain (From: header domain).

$dmarc_result

The DMARC result string, e.g. "pass" or "fail".

$dmarc_policy

The DMARC policy in effect: "none", "quarantine", or "reject".

$selector

Optional BIMI selector string. Defaults to "default". Pass the value returned by md_bimi_get_selector($entity) to honour the message's BIMI-Selector header.