(Excel) Create PKCS1 RSA Signature with PEM Private Key

See more RSA Examples

Demonstrates how to load a private key from a PEM file and create a PKCS1 RSA digital signature.

Download Excel Class Modules Chilkat Excel Class Modules

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

Dim pkey As Chilkat.PrivateKey
Set pkey = Chilkat.NewPrivateKey

' Load the private key from an RSA PEM file:

success = pkey.LoadPemFile("pvkey2_rsa.pem")

' Get the private key in XML format:
pkeyXml = pkey.GetXml()

Dim rsa As Chilkat.Rsa
Set rsa = Chilkat.NewRsa

' Import the private key into the RSA object:
success = rsa.ImportPrivateKey(pkeyXml)
If (success <> True) Then
    Debug.Print rsa.LastErrorText
    Exit Sub
End If

' Get the signature as hex.
rsa.EncodingMode = "hex"


strData = "This is the string to be signed."

' Sign the string using the sha-1 hash algorithm.
' Other valid choices are "md2", "md5", "sha256",
' "sha384", and "sha512".

hexSig = rsa.SignStringENC(strData,"sha-1")

Debug.Print hexSig

Debug.Print "Success!"