(PowerBuilder) CMS Sign Hash

Demonstrates how to use the SignHashENC method to sign a pre-computed hash. This method creates a CMS signature (PKCS7 detached signature).

This example requires Chilkat v9.5.0.90 or later.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

integer li_rc
oleobject loo_Crypt
string ls_Base64Hash
oleobject loo_Cert
integer li_Success
string ls_Base64CmsSig

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

loo_Crypt = create oleobject
// Use "Chilkat_9_5_0.Crypt2" for versions of Chilkat < 10.0.0
li_rc = loo_Crypt.ConnectToNewObject("Chilkat.Crypt2")
if li_rc < 0 then
    destroy loo_Crypt
    MessageBox("Error","Connecting to COM object failed")
    return
end if

// Create the hash to be signed...
loo_Crypt.HashAlgorithm = "sha256"
loo_Crypt.EncodingMode = "base64"
loo_Crypt.Charset = "utf-8"
// Create the SHA256 hash of a string using the utf-8 byte representation.
// Return the hash as base64.
ls_Base64Hash = loo_Crypt.HashStringENC("This is the string to be hashed")

// Load a certificate for signing.
loo_Cert = create oleobject
// Use "Chilkat_9_5_0.Cert" for versions of Chilkat < 10.0.0
li_rc = loo_Cert.ConnectToNewObject("Chilkat.Cert")

li_Success = loo_Cert.LoadPfxFile("qa_data/pfx/cert_test123.pfx","test123")
if li_Success = 0 then
    Write-Debug loo_Cert.LastErrorText
    destroy loo_Crypt
    destroy loo_Cert
    return
end if

loo_Crypt.SetSigningCert(loo_Cert)

// Sign the hash to create a base64 CMS signature (which does not contain the original data).
// We can get the signature in a single line of base64 by specifying "base64", or 
// we can get multi-line base64 by specifying "base64_mime".
loo_Crypt.EncodingMode = "base64_mime"
ls_Base64CmsSig = loo_Crypt.SignHashENC(ls_Base64Hash,"sha256","base64")
if loo_Crypt.LastMethodSuccess = 0 then
    Write-Debug loo_Crypt.LastErrorText
    destroy loo_Crypt
    destroy loo_Cert
    return
end if

// Note: In the above call to SignHashENC, the encoding of the returned CMS signature is specified by the EncodingMode property.
// However, the encoding of the passed-in hash is indicated by the 3rd argument.

Write-Debug "CMS Signature: " + ls_Base64CmsSig


destroy loo_Crypt
destroy loo_Cert