Xbase++

PKCS7 Sign Text using RSA 2048, SHA256, Base64 Output

See more Digital Signatures Examples

Demonstrates how to sign text using 2048-bit RSA with SHA256, producing PKCS#7 output in Base64. The certificate w/ private key used for signing is loaded from a .p12/.pfx file. Xbase++

LOCAL nSuccess
LOCAL oCert
LOCAL oCrypt
LOCAL cTextToSign
LOCAL cSigBase64

nSuccess := 0

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

oCert := CreateObject("Chilkat.Cert")

//  Load the cert and private key.  Whatever the private key happens to be,
//  such as RSA or ECC, then Chilkat will use it.  If the private key is 
//  a 2048-bit RSA key, then that's what will be used..
nSuccess := oCert:LoadPfxFile("qa_data/pfx/myCertAndKey.p12", "password")
IF (nSuccess != 1)
    ? oCert:LastErrorText
    oCert:destroy()
    RETURN
ENDIF

oCrypt := CreateObject("Chilkat.Crypt2")

nSuccess := oCrypt:SetSigningCert(oCert)
IF (nSuccess != 1)
    ? oCrypt:LastErrorText
    oCert:destroy()
    oCrypt:destroy()
    RETURN
ENDIF

//  Use SHA-256
oCrypt:HashAlgorithm := "sha256"

//  Hash the utf-8 byte representation of the string
oCrypt:Charset := "utf-8"

//  Return the result in base64
oCrypt:EncodingMode := "base64"

//  Sign some text..
cTextToSign := "This is the text to be hashed and signed."
cSigBase64 := oCrypt:OpaqueSignStringENC(cTextToSign)
IF (oCrypt:LastMethodSuccess != 1)
    ? oCrypt:LastErrorText
    oCert:destroy()
    oCrypt:destroy()
    RETURN
ENDIF

? cSigBase64

//  The result:
//  MIIS2wYJKoZIhvcNAQc ... zGeeY4Oxg==

oCert:destroy()
oCrypt:destroy()