Dart Requires Chilkat v11.0.0+

Send a Signed Email using RSASSA-PSS with SHA256

See more SMTP Examples

Demonstrates how to sign and send an email using the RSASSA-PSS signing algorithm with the SHA256 hash algorithm. . Dart

import 'package:chilkat/chilkat.dart';

void main() {
  // This example requires the Chilkat API to have been previously unlocked.
  // See Global Unlock Sample for sample code.

  // Get a digital certificate with private key from a .pfx
  // (Chilkat has many different ways to provide a cert + private key for siging.
  // Using a PFX is just one possible option.)
  final pfx = CkPfx();
  try {
    pfx.loadPfxFile('qa_data/rsassa-pss/privatekey.pfx', 'PFX_PASSWORD');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  final email = CkEmail();

  // Create a simple email.
  email.subject = 'Sample RSASSA-PSS Signed Email';
  email.body = 'Sample RSASSA-PSS Signed Email';
  email.from = 'from_name@mydomain.com';
  // Add one ore more recipients..
  email.addTo('Chilkat Support', 'support@chilkatsoft.com');
  email.addTo('Chilkat GMail', 'chilkat.support@gmail.com');

  // Indicate that the email is to be signed, and that we want to use RSASSA-PSS.
  email.sendSigned = true;
  email.signingAlg = 'pss';
  email.signingHashAlg = 'sha256';

  // Get the certificate to be used for signing.
  // (The typical case for a PFX is that it contains a cert with an associated private key,
  // as well as other certificates in the chain of authentication.  The cert with the private
  // key should be in the first position at index 0.)

  final cert = CkCert();
  try {
    pfx.certAt(0, cert);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Tell the email object to use this cert (and private key) for signing.
  email.setSigningCert(cert);

  final mailman = CkMailMan();

  // Set the SMTP settings for your email account on your mail server.
  mailman.smtpUsername = 'SMTP_LOGIN';
  mailman.smtpPassword = 'SMTP_PASSWORD';
  mailman.smtpHost = 'MY_SMTP_DOMAIN_OR_IP';
  mailman.smtpPort = 587;
  mailman.startTLS = true;

  // Signed email can be sent in two different ways.  
  // In a multipart/signed email, the signature is attached as a separate MIME part.
  // In an opaque email (signedData) the content of the email is encapsulated within the signature
  // and the email is sent as "application/pkcs7-mime". 
  // Either should be fine, but some receiving systems might require one or the other..
  mailman.opaqueSigning = false;

  // Send the email.  The mailman will sign the email as directed by the 
  // property settings of the email object.
  try {
    mailman.sendEmail(email);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  try {
    mailman.closeSmtpConnection();
  } on ChilkatException {
    print('Connection to SMTP server not closed cleanly.');
  }

  print('Mail Sent!');

  // -----------------------------------------------------------
  // This is the MIME of the RSASSA-PSS signed email that was sent

  // 	MIME-Version: 1.0
  // 	Date: Thu, 20 Apr 2017 10:14:58 -0500
  // 	Message-ID: <3682A87344CB3A4FB5EB5BC9908C0C4DA01DA461@CHILKAT13>
  // 	Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha256;
  // 	 boundary="------------050103020705000601010800"
  // 	X-Priority: 3 (Normal)
  // 	Subject: Sample RSASSA-PSS Signed Email
  // 	From: support@chilkatsoft.com
  // 	To: "Chilkat Support" <support@chilkatsoft.com>,
  // 	 "Chilkat GMail" <chilkat.support@gmail.com>
  // 
  // 	--------------050103020705000601010800
  // 	Content-Type: text/plain; format=flowed
  // 	Content-Transfer-Encoding: 7bit
  // 
  // 	Sample RSASSA-PSS Signed Email
  // 	--------------050103020705000601010800
  // 	Content-Transfer-Encoding: base64
  // 	Content-Type: application/pkcs7-signature; name="smime.p7s"
  // 	Content-Disposition: attachment; filename="smime.p7s"
  // 
  // 	MIIG5wYJKoZIhvcNAQcCoIIG2DCCBtQCAQExDzANBglghkgBZQMEAgEFADALBgkqhkiG9w0BBwGg
  // 	ggL4MIIC9DCCAl2gAwIBAgIJAMPsJCT11cniMA0GCSqGSIb3DQEBCwUAMIGSMQswCQYDVQQGEwJB
  // 	VTERMA8GA1UECAwIVmljdG9yaWExEjAQBgNVBAcMCU1lbGJvdXJuZTEhMB8GA1UECgwYSW50ZXJu
  // 	ZXQgV2lkZ2l0cyBQdHkgTHRkMQ8wDQYDVQQDDAZXaWRnZXQxKDAmBgkqhkiG9w0BCQEWGWFkbWlu
  // 	QGludGVybmV0d2lkZ2V0cy5jb20wHhcNMTYxMTAxMTY1MjMyWhcNMjExMDMxMTY1MjMyWjCBkjEL
  // 	MAkGA1UEBhMCQVUxETAPBgNVBAgMCFZpY3RvcmlhMRIwEAYDVQQHDAlNZWxib3VybmUxITAfBgNV
  // 	BAoMGEludGVybmV0IFdpZGdpdHMgUHR5IEx0ZDEPMA0GA1UEAwwGV2lkZ2V0MSgwJgYJKoZIhvcN
  // 	AQkBFhlhZG1pbkBpbnRlcm5ldHdpZGdldHMuY29tMIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKB
  // 	gQDGIdoCjyavs+F/Rm0VIB4m6O7VL1j+1IqieoR9NEX2GQvu2VCdceyxf9qaw1bxipEvjLwUkw7M
  // 	e+BTlLpWQbBMH87s6KpsC8MVyXhMLpP0oM8NFix/vLz2wdLhUh7CZvJA0plqkJk9bj57QIu+EO1k
  // 	tUHM2DFb6sckvCL2yybD1wIDAQABo1AwTjAdBgNVHQ4EFgQUONKKu2zsXIrinWxIGT654vrcQwsw
  // 	HwYDVR0jBBgwFoAUONKKu2zsXIrinWxIGT654vrcQwswDAYDVR0TBAUwAwEB/zANBgkqhkiG9w0B
  // 	AQsFAAOBgQArFvdi5u9i2QF1Qw+cdC1l7w2Y3+q6RIkln2W8rWJFje00644o8hXy7v46giJCedmF
  // 	ULlhm1n7XIsZGy2W3lJ77v5agn9gFwXu1h3cqkGXkoteE6SQJQXWgsW3GWPveObvTL8LF4y57fgM
  // 	9ZWS+V9MJajeu44Rf/tU17TLYKjvEjGCA7MwggOvAgEBMIGgMIGSMQswCQYDVQQGEwJBVTERMA8G
  // 	A1UECAwIVmljdG9yaWExEjAQBgNVBAcMCU1lbGJvdXJuZTEhMB8GA1UECgwYSW50ZXJuZXQgV2lk
  // 	Z2l0cyBQdHkgTHRkMQ8wDQYDVQQDDAZXaWRnZXQxKDAmBgkqhkiG9w0BCQEWGWFkbWluQGludGVy
  // 	bmV0d2lkZ2V0cy5jb20CCQDD7CQk9dXJ4jANBglghkgBZQMEAgEFAKCCAjQwGAYJKoZIhvcNAQkD
  // 	MQsGCSqGSIb3DQEHATAcBgkqhkiG9w0BCQUxDxcNMTcwNDIwMTUxNDU4WjAvBgkqhkiG9w0BCQQx
  // 	IgQgoHOtpFiAgti0cwDw46C8wyYSZbhx2yJqJZ/qRE8WPSQwXwYJKoZIhvcNAQkPMVIwUDALBglg
  // 	hkgBZQMEAQIwCgYIKoZIhvcNAwcwDgYIKoZIhvcNAwICAgCAMA0GCCqGSIb3DQMCAgFAMAcGBSsO
  // 	AwIHMA0GCCqGSIb3DQMCAgEoMIGxBgkrBgEEAYI3EAQxgaMwgaAwgZIxCzAJBgNVBAYTAkFVMREw
  // 	DwYDVQQIDAhWaWN0b3JpYTESMBAGA1UEBwwJTWVsYm91cm5lMSEwHwYDVQQKDBhJbnRlcm5ldCBX
  // 	aWRnaXRzIFB0eSBMdGQxDzANBgNVBAMMBldpZGdldDEoMCYGCSqGSIb3DQEJARYZYWRtaW5AaW50
  // 	ZXJuZXR3aWRnZXRzLmNvbQIJAMPsJCT11cniMIGzBgsqhkiG9w0BCRACCzGBo6CBoDCBkjELMAkG
  // 	A1UEBhMCQVUxETAPBgNVBAgMCFZpY3RvcmlhMRIwEAYDVQQHDAlNZWxib3VybmUxITAfBgNVBAoM
  // 	GEludGVybmV0IFdpZGdpdHMgUHR5IEx0ZDEPMA0GA1UEAwwGV2lkZ2V0MSgwJgYJKoZIhvcNAQkB
  // 	FhlhZG1pbkBpbnRlcm5ldHdpZGdldHMuY29tAgkAw+wkJPXVyeIwPQYJKoZIhvcNAQEKMDCgDTAL
  // 	BglghkgBZQMEAgGhGjAYBgkqhkiG9w0BAQgwCwYJYIZIAWUDBAIBogMCASAEgYCDQpT6vJZ9zERJ
  // 	JVX69PGUfCN5Eq9pKzoOTQSrIBe1YgNDSPd5pyOPP2MN1RpI0T/GTQZw4iWy5LZq0T5sjmk3fFVB
  // 	+VZjKtkTuhGaCdzMQXomVLBbI2fN4UaA4v1/Ayrqr8SY9Rsa20TpKv/bufK7oYs083UOtlcA1EHY
  // 	41wQ5A==
  // 
  // 	--------------050103020705000601010800--
}