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Visual FoxPro

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

Chilkat Visual FoxPro Downloads

Visual FoxPro
LOCAL lnSuccess
LOCAL loPkey
LOCAL loRsa
LOCAL lcStrData
LOCAL lcBase64Sig

lnSuccess = 0

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

loPkey = CreateObject('Chilkat.PrivateKey')

* Load the private key from an RSA PEM file:
lnSuccess = loPkey.LoadPemFile("myKey.pem")

loRsa = CreateObject('Chilkat.Rsa')

* Import the private key into the RSA component:
lnSuccess = loRsa.UsePrivateKey(loPkey)
IF (lnSuccess = 0) THEN
    ? loRsa.LastErrorText
    RELEASE loPkey
    RELEASE loRsa
    CANCEL
ENDIF

* OpenSSL uses BigEndian byte ordering:
loRsa.LittleEndian = 0

* The resulting signature will be a Base64 string:
loRsa.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.  
lcStrData = "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".
lcBase64Sig = loRsa.SignStringENC(lcStrData,"md5")

? lcBase64Sig

? "Success!"

RELEASE loPkey
RELEASE loRsa