(Xojo Plugin) RSA Hash Binary Data and Sign (and Verify)

Demonstrates how to sign the hash of binary data. Also demonstrates how to verify the RSA signature.

Note: This example requires Chilkat v11.0.0 or greater.

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

Dim success As Boolean
success = False

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

// Load an RSA private key for signing.
Dim privKey As New Chilkat.PrivateKey
success = privKey.LoadEncryptedPemFile("qa_data/pem/rsa_passwd.pem","passwd")
If (success = False) Then
    System.DebugLog(privKey.LastErrorText)
    Return
End If

Dim rsa As New Chilkat.Rsa
success = rsa.UsePrivateKey(privKey)

// We have some binary data (in hex) to sign
Dim originalData As String
originalData = "0102030405060708090A"
Dim bdData As New Chilkat.BinData
success = bdData.AppendEncoded(originalData,"hex")

// Hash (SHA-256) and sign the hash:
Dim bdSignature As New Chilkat.BinData
success = rsa.SignBd(bdData,"sha256",bdSignature)
If (success = False) Then
    System.DebugLog(rsa.LastErrorText)
    Return
End If

// Show the RSA signature in base64
System.DebugLog(bdSignature.GetEncoded("base64"))

// ------------------------------------------
// Get the public key from the private key
Dim pubKey As New Chilkat.PublicKey
success = privKey.ToPublicKey(pubKey)

// Verify the signature..
Dim rsa2 As New Chilkat.Rsa
success = rsa2.UsePublicKey(pubKey)

Dim bVerified As Boolean
bVerified = rsa2.VerifyBd(bdData,"sha256",bdSignature)
System.DebugLog("signature verified: " + Str(bVerified))