(Excel) 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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' This requires the Chilkat API to have been previously unlocked.
' See Global Unlock Sample for sample code.

Dim mime As Chilkat.Mime
Set mime = Chilkat.NewMime

' Create a MIME message to sign.
Dim success As Boolean
success = mime.NewMultipartMixed()
success = mime.AddHeaderField("someHeader1","Some value 1")
success = mime.AddHeaderField("someHeader2","Some value 2")

Dim part0 As Chilkat.Mime
Set part0 = Chilkat.NewMime
success = part0.AddHeaderField("hdrA","Some value A")
success = part0.AddHeaderField("hdrB","Some value B")
part0.ContentType = "text/plain"
part0.SetBody "This is the plain-text body."

Dim part1 As Chilkat.Mime
Set part1 = Chilkat.NewMime
success = part1.AddHeaderField("hdrX","Some value X")
success = part1.AddHeaderField("hdrY","Some value Y")
part1.ContentType = "text/xml"
part1.SetBody "<a>This is the XML body</a>"

success = mime.AppendPart(part0)
success = mime.AppendPart(part1)

' The MIME to be signed:
Dim sbUnsignedMime As Chilkat.StringBuilder
Set sbUnsignedMime = Chilkat.NewStringBuilder
success = mime.GetMimeSb(sbUnsignedMime)
Debug.Print 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.)
Dim pfx As Chilkat.Pfx
Set pfx = Chilkat.NewPfx
success = pfx.LoadPfxFile("qa_data/rsassa-pss/privatekey.pfx","PFX_PASSWORD")
If (success <> True) Then
    Debug.Print pfx.LastErrorText
    Exit Sub
End If

' 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.)

Set cert = pfx.GetCert(0)
If (pfx.LastMethodSuccess <> True) Then
    Debug.Print pfx.LastErrorText
    Exit Sub
End If

' Indicate that RSASSA-PSS with SHA256 should be used.
mime.SigningAlg = "pss"
mime.SigningHashAlg = "sha256"

' Add a detached signature.
success = mime.AddDetachedSignature(cert)
If (success <> True) Then
    Debug.Print mime.LastErrorText

    Exit Sub
End If

' Show the clear-signed MIME. (see the sample output below)
Debug.Print "-------------------------------------------------------------"
Debug.Print "Clear-signed MIME using detached signature:"
Debug.Print "-------------------------------------------------------------"
Debug.Print mime.GetMime()

' Restore the original unsigned MIME, and this time create an opaque signature.
success = mime.LoadMime(sbUnsignedMime.GetAsString())

' Sign using an opaque signature
success = mime.ConvertToSigned(cert)
If (success <> True) Then
    Debug.Print mime.LastErrorText

    Exit Sub
End If

' Show the opaque-signed MIME. (see the sample output below)
Debug.Print "-------------------------------------------------------------"
Debug.Print "Opaque-signed MIME :"
Debug.Print "-------------------------------------------------------------"
Debug.Print mime.GetMime()

Debug.Print "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
' 	ULlhm1n7XIsZGy2W3lJ77v5agn9gFwXu1h3cqkGXkoteE6SQJQXWgsW3GWPveObvTL8LF4y57fgM
' 	9ZWS+V9MJajeu44Rf/tU17TLYKjvEjGCA7MwggOvAgEBMIGgMIGSMQswCQYDVQQGEwJBVTERMA8G
' 	A1UECAwIVmljdG9yaWExEjAQBgNVBAcMCU1lbGJvdXJuZTEhMB8GA1UECgwYSW50ZXJuZXQgV2lk
' 	Z2l0cyBQdHkgTHRkMQ8wDQYDVQQDDAZXaWRnZXQxKDAmBgkqhkiG9w0BCQEWGWFkbWluQGludGVy
' 	bmV0d2lkZ2V0cy5jb20CCQDD7CQk9dXJ4jANBglghkgBZQMEAgEFAKCCAjQwGAYJKoZIhvcNAQkD
' 	MQsGCSqGSIb3DQEHATAcBgkqhkiG9w0BCQUxDxcNMTcwNDIwMTU1NDMyWjAvBgkqhkiG9w0BCQQx
' 	IgQgFEtkdw1+iBXvplXCUkOPlq66b+mDg+HBcChLn5YowD8wXwYJKoZIhvcNAQkPMVIwUDALBglg
' 	hkgBZQMEAQIwCgYIKoZIhvcNAwcwDgYIKoZIhvcNAwICAgCAMA0GCCqGSIb3DQMCAgFAMAcGBSsO
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' 	DwYDVQQIDAhWaWN0b3JpYTESMBAGA1UEBwwJTWVsYm91cm5lMSEwHwYDVQQKDBhJbnRlcm5ldCBX
' 	aWRnaXRzIFB0eSBMdGQxDzANBgNVBAMMBldpZGdldDEoMCYGCSqGSIb3DQEJARYZYWRtaW5AaW50
' 	ZXJuZXR3aWRnZXRzLmNvbQIJAMPsJCT11cniMIGzBgsqhkiG9w0BCRACCzGBo6CBoDCBkjELMAkG
' 	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
' 	MIGJAoGBAMYh2gKPJq+z4X9GbRUgHibo7tUvWP7UiqJ6hH00RfYZC+7ZUJ1x7LF/2prDVvGKkS+M
' 	vBSTDsx74FOUulZBsEwfzuzoqmwLwxXJeEwuk/Sgzw0WLH+8vPbB0uFSHsJm8kDSmWqQmT1uPntA
' 	i74Q7WS1QczYMVvqxyS8IvbLJsPXAgMBAAGjUDBOMB0GA1UdDgQWBBQ40oq7bOxciuKdbEgZPrni
' 	+txDCzAfBgNVHSMEGDAWgBQ40oq7bOxciuKdbEgZPrni+txDCzAMBgNVHRMEBTADAQH/MA0GCSqG
' 	SIb3DQEBCwUAA4GBACsW92Lm72LZAXVDD5x0LWXvDZjf6rpEiSWfZbytYkWN7TTrjijyFfLu/jqC
' 	IkJ52YVQuWGbWftcixkbLZbeUnvu/lqCf2AXBe7WHdyqQZeSi14TpJAlBdaCxbcZY+945u9MvwsX
' 	jLnt+Az1lZL5X0wlqN67jhF/+1TXtMtgqO8SMYIDszCCA68CAQEwgaAwgZIxCzAJBgNVBAYTAkFV
' 	MREwDwYDVQQIDAhWaWN0b3JpYTESMBAGA1UEBwwJTWVsYm91cm5lMSEwHwYDVQQKDBhJbnRlcm5l
' 	dCBXaWRnaXRzIFB0eSBMdGQxDzANBgNVBAMMBldpZGdldDEoMCYGCSqGSIb3DQEJARYZYWRtaW5A
' 	aW50ZXJuZXR3aWRnZXRzLmNvbQIJAMPsJCT11cniMA0GCWCGSAFlAwQCAQUAoIICNDAYBgkqhkiG
' 	9w0BCQMxCwYJKoZIhvcNAQcBMBwGCSqGSIb3DQEJBTEPFw0xNzA0MjAxNTU4NTNaMC8GCSqGSIb3
' 	DQEJBDEiBCBWTSl3s251U8fqOeSAzUp1Yue53X+UCWT0ux+fclE4FDBfBgkqhkiG9w0BCQ8xUjBQ
' 	MAsGCWCGSAFlAwQBAjAKBggqhkiG9w0DBzAOBggqhkiG9w0DAgICAIAwDQYIKoZIhvcNAwICAUAw
' 	BwYFKw4DAgcwDQYIKoZIhvcNAwICASgwgbEGCSsGAQQBgjcQBDGBozCBoDCBkjELMAkGA1UEBhMC
' 	QVUxETAPBgNVBAgMCFZpY3RvcmlhMRIwEAYDVQQHDAlNZWxib3VybmUxITAfBgNVBAoMGEludGVy
' 	bmV0IFdpZGdpdHMgUHR5IEx0ZDEPMA0GA1UEAwwGV2lkZ2V0MSgwJgYJKoZIhvcNAQkBFhlhZG1p
' 	bkBpbnRlcm5ldHdpZGdldHMuY29tAgkAw+wkJPXVyeIwgbMGCyqGSIb3DQEJEAILMYGjoIGgMIGS
' 	MQswCQYDVQQGEwJBVTERMA8GA1UECAwIVmljdG9yaWExEjAQBgNVBAcMCU1lbGJvdXJuZTEhMB8G
' 	A1UECgwYSW50ZXJuZXQgV2lkZ2l0cyBQdHkgTHRkMQ8wDQYDVQQDDAZXaWRnZXQxKDAmBgkqhkiG
' 	9w0BCQEWGWFkbWluQGludGVybmV0d2lkZ2V0cy5jb20CCQDD7CQk9dXJ4jA9BgkqhkiG9w0BAQow
' 	MKANMAsGCWCGSAFlAwQCAaEaMBgGCSqGSIb3DQEBCDALBglghkgBZQMEAgGiAwIBIASBgILtktxt
' 	tXWMWio7hLcvHUWk0Q3jP3rRdgNhcd/NdZsgDFP9/aq8/nHLLHSWfSh1PH+eZeKJwXxUH4Lwk6Sm
' 	xFt97jyi3HaC3fezUSEqyg5WFG6fwOZGK4qF0WF+q29lvyNyV3iIQgDWxZQOcVL2fhpqUjoytkxj
' 	/QTfrLOuzXKy
'