Chilkat2-Python

RSA Sign using a Private Key on a USB Token or Smartcard

See more Apple Keychain Examples

Create an RSA signature using a private key stored on a USB token or smartcard.

Note: On MacOS and iOS, this example requires Chilkat v10.1.2 or later when the Apple Keychain is used as the underlying means to do the signing.

Chilkat2-Python

import sys
import chilkat2

success = False

# Assuming the smartcard/USB token is installed with the correct drivers from the manufacturer,
# this code can work on multiple platforms including Windows, MacOS, Linux, and iOS.

# Chilkat automatically detects and determines the way in which the HSM is used,
# which can be by PKCS11, Apple Keychain, Microsoft CNG / Crypto API, or ScMinidriver.

cert = chilkat2.Cert()

# Set the token/smartcard PIN prior to loading.
cert.SmartCardPin = "123456"

# Specify the certificate by its common name.
success = cert.LoadFromSmartcard("cn=chilkat-rsa-2048")
if (success == False):
    print(cert.LastErrorText)
    sys.exit()

print("Signing with cert: " + cert.SubjectCN)

# Create data to be hashed and signed.
bd = chilkat2.BinData()

for i in range(0,101):
    bd.AppendEncoded("000102030405060708090A0B0C0D0E0F","hex")

rsa = chilkat2.Rsa()

# Use the certificate's private key for signing.
success = rsa.SetX509Cert(cert,True)
if (success == False):
    print(rsa.LastErrorText)
    sys.exit()

# Sign the SHA-256 hash of the contents of bd.
bdSig = chilkat2.BinData()
success = rsa.SignBd(bd,"sha256",bdSig)
if (success == False):
    print(rsa.LastErrorText)
    sys.exit()

# The RSA signature is equal in length to the size of the RSA key.
print("Output signature size in bits = " + str(bdSig.NumBytes * 8))

# We can save the signature for later verification..
bdSig.WriteFile("rsaSignatures/test1.sig")

# See the example to verify the RSA signature:
# Verfies an RSA Signature