(Xojo Plugin) Duplicate openssl dgst -sha256 -sign private.pem -out sha256.sig in.dat

Demonstrates how to duplicate this OpenSSL command:

openssl dgst -sha256 -sign private.pem -out sha256.sig in.dat

1. Creates a SHA256 digest of the contents of the input file
2. Signs the SHA256 digest using the private key.

Chilkat Xojo Plugin Download Xojo Plugin for Windows, Linux, Mac OS X, and ARM, ARM64

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

Dim pkey As New Chilkat.PrivateKey

// Load the private key from an PEM file:
Dim success As Boolean
success = pkey.LoadPemFile("private.pem")
If (success <> True) Then
    System.DebugLog(pkey.LastErrorText)
    Return
End If

Dim rsa As New Chilkat.Rsa

// Import the private key into the RSA component:
success = rsa.ImportPrivateKeyObj(pkey)
If (success <> True) Then
    System.DebugLog(rsa.LastErrorText)
    Return
End If

// OpenSSL uses big-endian.
rsa.LittleEndian = False

// Load the file to be signed.
Dim bdFileData As New Chilkat.BinData
success = bdFileData.LoadFile("in.dat")

Dim bdSig As New Chilkat.BinData
success = rsa.SignBd(bdFileData,"sha256",bdSig)
If (success <> True) Then
    System.DebugLog(rsa.LastErrorText)
    Return
End If

// Save the binary signature to a file.
success = bdSig.WriteFile("signature.sig")
If (success <> True) Then
    System.DebugLog("Failed to write signature.sig.")
    Return
End If

System.DebugLog("Success.")