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Xojo Plugin Requires Chilkat v11.0.0+

Duplicate openssl dgst -md5 -sign myKey.pem something.txt | openssl enc -base64 -A

See more RSA Examples

Demonstrates how to duplicate the creation of an RSA signature produced by this OpenSSL command:
openssl dgst -md5 -sign myKey.pem something.txt | openssl enc -base64 -A

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Xojo Plugin
Dim success As Boolean
success = False

//  This example assumes 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 RSA PEM file:
success = pkey.LoadPemFile("myKey.pem")

Dim rsa As New Chilkat.Rsa

//  Import the private key into the RSA component:
success = rsa.UsePrivateKey(pkey)
If (success = False) Then
    System.DebugLog(rsa.LastErrorText)
    Return
End If

//  OpenSSL uses BigEndian byte ordering:
rsa.LittleEndian = False

//  The resulting signature will be a Base64 string:
rsa.EncodingMode = "base64"

//  For simplicity, we're not loading
//  the data to be signed from a file.  We are instead simply
//  using a literal string value.  
Dim strData As String
strData = "This is the text to be signed."

//  Hash the input using MD5, and then sign the hash:
//  Other valid hash algorithm choices are "md2" and "sha-1".
Dim base64Sig As String
base64Sig = rsa.SignStringENC(strData,"md5")

System.DebugLog(base64Sig)

System.DebugLog("Success!")