Perl

Send DKIM Signed Email

See more DKIM / DomainKey Examples

Demonstrates how to send DKIM signed email. Chilkat2 Perl

use strict;
use warnings;
use Chilkat2;

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

my $mailman = Chilkat2::MailMan->new;
my $dkim = Chilkat2::Dkim->new;

# SMTP server settings...
$mailman->SmtpHost('SMTP_DOMAIN');
$mailman->SmtpUsername('SMTP_LOGIN');
$mailman->SmtpPassword('SMTP_PASSWORD');
$mailman->SmtpPort(465);
$mailman->SmtpSsl(1);

my $email = Chilkat2::Email->new;

$email->Subject('This is a test');
$email->Body('This is a test');
$email->From('Chilkat Support <support@chilkatsoft.com>');

# Add some recipients (BCC recipients are added below)
$email->AddTo('Chilkat Software', 'chilkat_software@yahoo.com');
$email->AddTo('Chilkat Admin', 'admin@chilkatsoft.com');
$email->AddCC('Chilkat Admin', 'admin@chilkat.io');

# When sending an email with a DKIM signature, the MIME
# of the email must not be modified prior to
# or during the sending process.  Therefore, the MIME of the
# email is assembled, the DKIM signature is added, and then
# SendMimeBd is called to send the email.

# First get the MIME of the email.  Calling RenderToMimeBd
# causes the email to be signed and/or encrypted if those options
# have been selected.  The MIME returned by RenderToMimeBd
# is the exact MIME that would've been sent if SendEmail was
# called.  We'll add a DKIM signature header to this MIME and then send...
my $bdMime = Chilkat2::BinData->new;
my $success = $mailman->RenderToMimeBd($email, $bdMime);
if (!$success) {
    print $mailman->LastErrorText, "\n";
    exit;
}

# To create a DKIM signature,
# you'll need to provide the following:
# (1) An RSA private key in any common file format.
# (2) The domain name (typically the same domain
# as the sender of an email).
# (3) A selector for the domain name -- an arbitrary string
# to identify the matching public key in DNS.

# To allow an email recipient to verify the DKIM signature via an
# external email client supporting DKIM or using other software,
# you will need to create a DNS record with the selector
# and matching public key.  This example does not provide
# information about DKIM DNS record creation.
# (Chilkat does not provide an API for creating DNS records.
# Creating the DKIM DNS record is something you would do
# manually.)

# Set the domain and selector:
# You'll need to provide your own values here..
$dkim->DkimDomain('chilkatsoft.com');
$dkim->DkimSelector('brisbane');

# Load a private key from any common RSA private key
# format, such as DER, PKCS8, PEM, XML, etc.
# The LoadDkimPkFile method automatically detects
# the file format and reads it appropriately.
# If a password is not required, you'll still need to provide
# an empty password string argument, but it is ignored.
my $password = 'passwd';
my $privKey = Chilkat2::PrivateKey->new;
$success = $privKey->LoadAnyFormatFile('qa_data/pem/rsa_passwd.pem', $password);
if (!$success) {
    print $privKey->LastErrorText, "\n";
    exit;
}

$success = $dkim->SetDkimPrivateKey($privKey);
if (!$success) {
    print $dkim->LastErrorText, "\n";
    exit;
}

# Add the DKIM-Signature header to the MIME in bdMime
$success = $dkim->DkimSign($bdMime);
if (!$success) {
    print $dkim->LastErrorText, "\n";
    exit;
}

# If desired, examine the MIME of the email being sent.
$bdMime->WriteFile('qa_output/dkimSigned.eml');

# ---- Prepare to send the email contained in bdMime ---

# To send to multiple email addresses, the strRecipients should be set to a comma-separated
# list of email addresses.

# Note: This is where we can add additional BCC addreses.
# Here we are adding "chilkat.support@gmail.com" as an additional BCC address.
# Notice that the 1st three email addresses are NOT BCC because these email addresses
# appear in the MIME header of the email (in the "To" and "CC" header fields).
# A BCC email address does not appear in the MIME, and thus the non-BCC recipients cannot see
# that the email was also sent to the BCC address.  (BCC means "blind carbon copy")
my $strRecipients = 'chilkat_software@yahoo.com, admin@chilkatsoft.com, admin@chilkat.io, chilkat.support@gmail.com';
my $strFrom = 'support@chilkatsoft.com';

$success = $mailman->SendMimeBd($strFrom, $strRecipients, $bdMime);
if (!$success) {
    print $mailman->LastErrorText, "\n";
    exit;
}

$success = $mailman->CloseSmtpConnection();
if (!$success) {
    print "Connection to SMTP server not closed cleanly.\n";
}

print "DKIM Signed Mail Sent!\n";