md_dkim_sign
Returns a mail header and the DKIM signature for the message. The
method accepts the following parameters:
$keyfile
The path to the private DKIM key
$algorithm
The algorithm to be used to sign the message, by default is
'rsa-sha1'
$method
The method used to sign the message, by default is 'relaxed'
$domain
The domain to be used when signing the message, by default it's
autodetected
$selector
The selector to be used when signing the message, by default
it's 'default'
$headers
The headers to sign, by default the headers are: From Sender
Reply-To Subject Date Message-ID To Cc MIME-Version Content-Type
Content-Transfer-Encoding Content-ID Content-Description
Resent-Date Resent-From Resent-Sender Resent-To Resent-cc
Resent-Message-ID In-Reply-To References List-Id List-Help
List-Unsubscribe List-Subscribe List-Post List-Owner
List-Archive
md_dkim_verify
Verifies the DKIM signature of an email. Return value can be "pass",
"fail", "invalid", "temperror", "none". In case of multiple
signatures, the "best" result will be returned. Best is defined as
"pass", followed by "fail", "invalid", and "none". The second return
value is the domain that has applied the signature. The third return
value is the size of the DKIM public key. The forth return value is
the value of the "b" tag of the DKIM signature.