CkPython

RSA Sign an Encoded Hash

See more RSA Examples

Demonstrates signing a hash (e.g., SHA256) provided as an encoded string (e.g., base64 or hex). CkPython

import sys
import chilkat

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 = chilkat.CkCert()

# Set the token/smartcard PIN prior to loading.
cert.put_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 the private key for this cert: " + cert.subjectCN())

# Create data to be hashed and signed.
bd = chilkat.CkBinData()

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

rsa = chilkat.CkRsa()

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

# We'll first compute the hash and then pass the encoded hash to be signed.
sha256_base64 = bd.getHash("sha256","base64")
print("sha256 hash in base64 format: " + sha256_base64)

# Pass in the base64 hash and return a base64 signature.
rsa.put_EncodingMode("base64")
rsaSig_base64 = rsa.signHashENC(sha256_base64,"sha256")
if (success == False):
    print(rsa.lastErrorText())
    sys.exit()

print("RSA signature as base64: " + rsaSig_base64)