PowerShell

Send DKIM Signed Email

See more DKIM / DomainKey Examples

Demonstrates how to send DKIM signed email. PowerShell

Add-Type -Path "C:\chilkat\ChilkatDotNet47-x64\ChilkatDotNet47.dll"

$success = $false

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

$mailman = New-Object Chilkat.MailMan
$dkim = New-Object Chilkat.Dkim

# SMTP server settings...
$mailman.SmtpHost = "SMTP_DOMAIN"
$mailman.SmtpUsername = "SMTP_LOGIN"
$mailman.SmtpPassword = "SMTP_PASSWORD"
$mailman.SmtpPort = 465
$mailman.SmtpSsl = $true

$email = New-Object Chilkat.Email

$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...
$bdMime = New-Object Chilkat.BinData
$success = $mailman.RenderToMimeBd($email,$bdMime)
if ($success -eq $false) {
    $($mailman.LastErrorText)
    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.
$password = "passwd"
$privKey = New-Object Chilkat.PrivateKey
$success = $privKey.LoadAnyFormatFile("qa_data/pem/rsa_passwd.pem",$password)
if ($success -eq $false) {
    $($privKey.LastErrorText)
    exit
}

$success = $dkim.SetDkimPrivateKey($privKey)
if ($success -eq $false) {
    $($dkim.LastErrorText)
    exit
}

# Add the DKIM-Signature header to the MIME in bdMime
$success = $dkim.DkimSign($bdMime)
if ($success -eq $false) {
    $($dkim.LastErrorText)
    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")
$strRecipients = "chilkat_software@yahoo.com, admin@chilkatsoft.com, admin@chilkat.io, chilkat.support@gmail.com"
$strFrom = "support@chilkatsoft.com"

$success = $mailman.SendMimeBd($strFrom,$strRecipients,$bdMime)
if ($success -eq $false) {
    $($mailman.LastErrorText)
    exit
}

$success = $mailman.CloseSmtpConnection()
if ($success -ne $true) {
    $("Connection to SMTP server not closed cleanly.")
}

$("DKIM Signed Mail Sent!")