Perl Requires Chilkat v11.0.0+
Send a Signed Email using RSASSA-PSS with SHA256

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

Perl
use chilkat();

$success = 0;

#  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.)
$pfx = chilkat::CkPfx->new();
$success = $pfx->LoadPfxFile("qa_data/rsassa-pss/privatekey.pfx","PFX_PASSWORD");
if ($success == 0) {
    print $pfx->lastErrorText() . "\r\n";
    exit;
}

$email = chilkat::CkEmail->new();

#  Create a simple email.
$email->put_Subject("Sample RSASSA-PSS Signed Email");
$email->put_Body("Sample RSASSA-PSS Signed Email");
$email->put_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->put_SendSigned(1);
$email->put_SigningAlg("pss");
$email->put_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.)

$cert = chilkat::CkCert->new();
$success = $pfx->CertAt(0,$cert);
if ($success == 0) {
    print $pfx->lastErrorText() . "\r\n";
    exit;
}

#  Tell the email object to use this cert (and private key) for signing.
$email->SetSigningCert($cert);

$mailman = chilkat::CkMailMan->new();

#  Set the SMTP settings for your email account on your mail server.
$mailman->put_SmtpUsername("SMTP_LOGIN");
$mailman->put_SmtpPassword("SMTP_PASSWORD");
$mailman->put_SmtpHost("MY_SMTP_DOMAIN_OR_IP");
$mailman->put_SmtpPort(587);
$mailman->put_StartTLS(1);

#  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->put_OpaqueSigning(0);

#  Send the email.  The mailman will sign the email as directed by the 
#  property settings of the email object.
$success = $mailman->SendEmail($email);
if ($success == 0) {
    print $mailman->lastErrorText() . "\r\n";
    exit;
}

$success = $mailman->CloseSmtpConnection();
if ($success != 1) {
    print "Connection to SMTP server not closed cleanly." . "\r\n";
}

print "Mail Sent!" . "\r\n";

#  -----------------------------------------------------------
#  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--