Select Encryption Algorithm with SMTP Encrypted Email

Demonstrates how to select the encryption algorithm and strength (key size) when sending encrypted email.

Download Chilkat Ruby Library

require 'chilkat'

#  The mailman object is used for sending and receiving email.
mailman = Chilkat::CkMailMan.new()

#  Any string argument automatically begins the 30-day trial.
success = mailman.UnlockComponent("30-day trial")
if (success != true)
    print "Component unlock failed" + "\n"
    exit
end

#  Set the SMTP server.
mailman.put_SmtpHost("smtp.comcast.net")

#  Create a new email object
email = Chilkat::CkEmail.new()

email.put_Subject("This email is encrypted")
email.put_Body("This is a digitally encrypted mail")
email.put_From("Chilkat Support <support@chilkatsoft.com>")
email.AddTo("Chilkat Admin","admin@chilkatsoft.com")

#  In this example, we've already installed the certificate for "admin@chilkatsoft.com"
#  in the current user's personal certificate store.
#  If the email.SendEncrypted property is set, Chilkat will
#  automatically search for and use the first non-expired certificate
#  matching the recipient's email address.  Chilkat searches
#  the Current User's Personal certificate store, as well
#  as the Local Machine's Personal certificate store.
#  Run certmgr.msc to view the certs in the Current User's
#  certificate store.
email.put_SendEncrypted(true)

#  Use the CSP object to select an encryption algorithm:
csp = Chilkat::CkCSP.new()
#  Make sure we're using the enhanced provider, which provides
#  access to stronger algorithms.
csp.SetProviderMicrosoftEnhanced()

#  Select 168-bit 3DES (i.e. 192-bit DES if you include the parity bits)
csp.SetEncryptAlgorithm("3DES")

#  Tell the email to use this CSP:
email.SetCSP(csp)

success = mailman.SendEmail(email)
if (success != true)
    print mailman.lastErrorText() + "\n"
else
    #  Examine the LastErrorText anyway, so we can see
    #  that 3DES was used...
    #  You should see these lines in the log:
    #  alg_name: 3DES
    #  alg_bits: 168
    print mailman.lastErrorText() + "\n"
end