RSA Signature with Certificate's Private Key from PFX

Demonstrates how to use a certificate's private key from a PFX file to create an RSA signature.

Downloads for Windows/Linux and Install Instructions

require 'rubygems'
require 'chilkat'



#  Create an instance of a certificate store object, load a PFX file,
#  locate the certificate we need, and use it for signing.
#  (a PFX file may contain more than one certificate.)
certStore = Chilkat::CkCertStore.new()

#  The 1st argument is the filename, the 2nd arg is the
#  PFX file's password:
success = certStore.LoadPfxFile("chilkat.pfx","test")
if (success != true)
    print certStore.lastErrorText() + "\n"
    exit
end

# cert is a CkCert
cert = certStore.FindCertBySubject("Chilkat Software, Inc.")
if (cert == nil )
    print certStore.lastErrorText() + "\n"
    exit
end

# pkey is a CkPrivateKey
pkey = cert.ExportPrivateKey()
if (pkey == nil )
    print cert.lastErrorText() + "\n"
    exit
end

#  Get the private key in XML format:
pkeyXml = pkey.getXml()

rsa = Chilkat::CkRsa.new()

#  Any string argument automatically begins the 30-day trial.
success = rsa.UnlockComponent("30-day trial")
if (success != true)
    print "RSA component unlock failed" + "\n"
    exit
end

#  Import the private key into the RSA component:
success = rsa.ImportPrivateKey(pkeyXml)
if (success != true)
    print rsa.lastErrorText() + "\n"
    exit
end

#  This example will sign a string, and receive the signature
#  in a hex-encoded string.  Therefore, set the encoding mode
#  to "hex":
rsa.put_EncodingMode("hex")

#  If some other non-Chilkat application or web service is going to be verifying
#  the signature, it is important to match the byte-ordering.
#  The LittleEndian property may be set to true
#  for little-endian byte ordering,
#  or false  for big-endian byte ordering.
#  Microsoft apps typically use little-endian, while
#  OpenSSL and other services (such as Amazon CloudFront)
#  use big-endian.
rsa.put_LittleEndian(false)

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

#  Sign the string using the sha-1 hash algorithm.
#  Other valid choices are "md2" and "md5".
hexSig = rsa.signStringENC(strData,"sha-1")

print hexSig + "\n";

print "Success!" + "\n"