(Java) Sign MIME using RSASSA-PSS with SHA256

Demonstrates how to sign an MIME using the RSASSA-PSS signing algorithm with the SHA256 hash algorithm.

Note: This example requires Chilkat v9.5.0.67 or greater.

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import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    // This requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    boolean success;
    CkMime mime = new CkMime();

    // Create a MIME message to sign.
    mime.NewMultipartMixed();
    mime.AddHeaderField("someHeader1","Some value 1");
    mime.AddHeaderField("someHeader2","Some value 2");

    CkMime part0 = new CkMime();
    part0.AddHeaderField("hdrA","Some value A");
    part0.AddHeaderField("hdrB","Some value B");
    part0.put_ContentType("text/plain");
    part0.SetBody("This is the plain-text body.");

    CkMime part1 = new CkMime();
    part1.AddHeaderField("hdrX","Some value X");
    part1.AddHeaderField("hdrY","Some value Y");
    part1.put_ContentType("text/xml");
    part1.SetBody("<a>This is the XML body</a>");

    mime.AppendPart(part0);
    mime.AppendPart(part1);

    // The MIME to be signed:
    CkStringBuilder sbUnsignedMime = new CkStringBuilder();
    mime.GetMimeSb(sbUnsignedMime);
    System.out.println(sbUnsignedMime.getAsString());

    // 	Content-Type: multipart/mixed; boundary="------------080303020600020604010008"
    // 	someHeader1: Some value 1
    // 	someHeader2: Some value 2
    // 
    // 	--------------080303020600020604010008
    // 	hdrA: Some value A
    // 	hdrB: Some value B
    // 	Content-Type: text/plain
    // 
    // 	This is the plain-text body.
    // 	--------------080303020600020604010008
    // 	hdrX: Some value X
    // 	hdrY: Some value Y
    // 	Content-Type: text/xml
    // 
    // 	<a>This is the XML body</a>
    // 	--------------080303020600020604010008--
    // 

    // 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.)
    CkPfx pfx = new CkPfx();
    success = pfx.LoadPfxFile("qa_data/rsassa-pss/privatekey.pfx","PFX_PASSWORD");
    if (success != true) {
        System.out.println(pfx.lastErrorText());
        return;
        }

    // 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.)
    CkCert cert = pfx.GetCert(0);
    if (pfx.get_LastMethodSuccess() != true) {
        System.out.println(pfx.lastErrorText());
        return;
        }

    // Indicate that RSASSA-PSS with SHA256 should be used.
    mime.put_SigningAlg("pss");
    mime.put_SigningHashAlg("sha256");

    // Add a detached signature.
    success = mime.AddDetachedSignature(cert);
    if (success != true) {
        System.out.println(mime.lastErrorText());

        return;
        }

    // Show the clear-signed MIME. (see the sample output below)
    System.out.println("-------------------------------------------------------------");
    System.out.println("Clear-signed MIME using detached signature:");
    System.out.println("-------------------------------------------------------------");
    System.out.println(mime.getMime());

    // Restore the original unsigned MIME, and this time create an opaque signature.
    mime.LoadMime(sbUnsignedMime.getAsString());

    // Sign using an opaque signature
    success = mime.ConvertToSigned(cert);
    if (success != true) {
        System.out.println(mime.lastErrorText());

        return;
        }

    // Show the opaque-signed MIME. (see the sample output below)
    System.out.println("-------------------------------------------------------------");
    System.out.println("Opaque-signed MIME :");
    System.out.println("-------------------------------------------------------------");
    System.out.println(mime.getMime());

    System.out.println("Success.");

    // -----------------------------------------------
    // This is sample output for the clear-signed MIME:
    // -----------------------------------------------
    // 
    // 	Content-Type: multipart/signed; boundary="----=_NextPart_672_c95a_97b64c9a.90b5204d";
    // 	 protocol="application/x-pkcs7-signature";
    // 	 micalg=sha256
    // 
    // 	------=_NextPart_672_c95a_97b64c9a.90b5204d
    // 	Content-Type: multipart/mixed; boundary="------------030207090102000301050504"
    // 	someHeader1: Some value 1
    // 	someHeader2: Some value 2
    // 
    // 	--------------030207090102000301050504
    // 	hdrA: Some value A
    // 	hdrB: Some value B
    // 	Content-Type: text/plain
    // 
    // 	This is the plain-text body.
    // 	--------------030207090102000301050504
    // 	hdrX: Some value X
    // 	hdrY: Some value Y
    // 	Content-Type: text/xml
    // 
    // 	<a>This is the XML body</a>
    // 	--------------030207090102000301050504--
    // 
    // 	------=_NextPart_672_c95a_97b64c9a.90b5204d
    // 	Content-Transfer-Encoding: base64
    // 	Content-Type: application/x-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
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    // 	9ZWS+V9MJajeu44Rf/tU17TLYKjvEjGCA7MwggOvAgEBMIGgMIGSMQswCQYDVQQGEwJBVTERMA8G
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    // 	A1UEBhMCQVUxETAPBgNVBAgMCFZpY3RvcmlhMRIwEAYDVQQHDAlNZWxib3VybmUxITAfBgNVBAoM
    // 	GEludGVybmV0IFdpZGdpdHMgUHR5IEx0ZDEPMA0GA1UEAwwGV2lkZ2V0MSgwJgYJKoZIhvcNAQkB
    // 	FhlhZG1pbkBpbnRlcm5ldHdpZGdldHMuY29tAgkAw+wkJPXVyeIwPQYJKoZIhvcNAQEKMDCgDTAL
    // 	BglghkgBZQMEAgGhGjAYBgkqhkiG9w0BAQgwCwYJYIZIAWUDBAIBogMCASAEgYAvqIqKBzNXyVbh
    // 	TmaxdAc4d0ZTqWT6Na3C+DMO8owSKWy5FdGbJ2DLKm92qe/KLPTcj51vuwLUQb0Sw7r5Xknl+/6p
    // 	Eqn2qe/6hgDn06vvzNofVAweOtSVJsBO7/cYYPc+pXZZ2BcpZDdf/9Ci56Yrlk7A72BeqPe47J3F
    // 	neC8qw==
    // 
    // 	------=_NextPart_672_c95a_97b64c9a.90b5204d--
    // 

    // -----------------------------------------------
    // This is sample output for the opaque-signed MIME:
    // -----------------------------------------------
    // 	Content-Type: application/x-pkcs7-mime; name="smime.p7m"; smime-type="signed-data"
    // 	someHeader1: Some value 1
    // 	someHeader2: Some value 2
    // 	Content-Disposition: attachment; filename="smime.p7m"
    // 	Content-Transfer-Encoding: base64
    // 
    // 	MIIItAYJKoZIhvcNAQcCoIIIpTCCCKECAQExDzANBglghkgBZQMEAgEFADCCAdYGCSqGSIb3DQEH
    // 	AaCCAccEggHDQ29udGVudC1UeXBlOiBtdWx0aXBhcnQvbWl4ZWQ7IGJvdW5kYXJ5PSItLS0tLS0t
    // 	LS0tLS0wMDA2MDcwNzA3MDcwMTA1MDAwMTA5MDciDQpzb21lSGVhZGVyMTogU29tZSB2YWx1ZSAx
    // 	DQpzb21lSGVhZGVyMjogU29tZSB2YWx1ZSAyDQoNCi0tLS0tLS0tLS0tLS0tMDAwNjA3MDcwNzA3
    // 	MDEwNTAwMDEwOTA3DQpoZHJBOiBTb21lIHZhbHVlIEENCmhkckI6IFNvbWUgdmFsdWUgQg0KQ29u
    // 	dGVudC1UeXBlOiB0ZXh0L3BsYWluDQoNClRoaXMgaXMgdGhlIHBsYWluLXRleHQgYm9keS4NCi0t
    // 	LS0tLS0tLS0tLS0tMDAwNjA3MDcwNzA3MDEwNTAwMDEwOTA3DQpoZHJYOiBTb21lIHZhbHVlIFgN
    // 	Cmhkclk6IFNvbWUgdmFsdWUgWQ0KQ29udGVudC1UeXBlOiB0ZXh0L3htbA0KDQo8YT5UaGlzIGlz
    // 	IHRoZSBYTUwgYm9keTwvYT4NCi0tLS0tLS0tLS0tLS0tMDAwNjA3MDcwNzA3MDEwNTAwMDEwOTA3
    // 	LS0NCqCCAvgwggL0MIICXaADAgECAgkAw+wkJPXVyeIwDQYJKoZIhvcNAQELBQAwgZIxCzAJBgNV
    // 	BAYTAkFVMREwDwYDVQQIDAhWaWN0b3JpYTESMBAGA1UEBwwJTWVsYm91cm5lMSEwHwYDVQQKDBhJ
    // 	bnRlcm5ldCBXaWRnaXRzIFB0eSBMdGQxDzANBgNVBAMMBldpZGdldDEoMCYGCSqGSIb3DQEJARYZ
    // 	YWRtaW5AaW50ZXJuZXR3aWRnZXRzLmNvbTAeFw0xNjExMDExNjUyMzJaFw0yMTEwMzExNjUyMzJa
    // 	MIGSMQswCQYDVQQGEwJBVTERMA8GA1UECAwIVmljdG9yaWExEjAQBgNVBAcMCU1lbGJvdXJuZTEh
    // 	MB8GA1UECgwYSW50ZXJuZXQgV2lkZ2l0cyBQdHkgTHRkMQ8wDQYDVQQDDAZXaWRnZXQxKDAmBgkq
    // 	hkiG9w0BCQEWGWFkbWluQGludGVybmV0d2lkZ2V0cy5jb20wgZ8wDQYJKoZIhvcNAQEBBQADgY0A
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    // 	vBSTDsx74FOUulZBsEwfzuzoqmwLwxXJeEwuk/Sgzw0WLH+8vPbB0uFSHsJm8kDSmWqQmT1uPntA
    // 	i74Q7WS1QczYMVvqxyS8IvbLJsPXAgMBAAGjUDBOMB0GA1UdDgQWBBQ40oq7bOxciuKdbEgZPrni
    // 	+txDCzAfBgNVHSMEGDAWgBQ40oq7bOxciuKdbEgZPrni+txDCzAMBgNVHRMEBTADAQH/MA0GCSqG
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    // 	jLnt+Az1lZL5X0wlqN67jhF/+1TXtMtgqO8SMYIDszCCA68CAQEwgaAwgZIxCzAJBgNVBAYTAkFV
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    // 	MQswCQYDVQQGEwJBVTERMA8GA1UECAwIVmljdG9yaWExEjAQBgNVBAcMCU1lbGJvdXJuZTEhMB8G
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    // 	MKANMAsGCWCGSAFlAwQCAaEaMBgGCSqGSIb3DQEBCDALBglghkgBZQMEAgGiAwIBIASBgILtktxt
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    // 	xFt97jyi3HaC3fezUSEqyg5WFG6fwOZGK4qF0WF+q29lvyNyV3iIQgDWxZQOcVL2fhpqUjoytkxj
    // 	/QTfrLOuzXKy
    // 
  }
}