(Chilkat2-Python) RSA Encrypt and Decrypt Credit Card Numbers

Chilkat2-Python sample code to RSA public-key encrypt and decrypt credit card numbers. The RSA key is loaded from an unencrypted PKCS8 file. Chilkat provides many ways of setting the key -- loading from both encrypted and unencrypted PEM, PKCS8, DER, PVK, etc. Keys may be loaded from files or in-memory representations. (The RSA component also provides the ability to generate RSA keys.)

Note: This example requires Chilkat v11.0.0 or greater.

Chilkat2 Python Downloads install with pip pip3 install chilkat2 or download... Python Module for Windows, Linux, Alpine Linux, MacOS

import sys
import chilkat2

success = False

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

rsa = chilkat2.Rsa()

privKey = chilkat2.PrivateKey()

# Load an RSA private key from a file:
success = privKey.LoadAnyFormatFile("rsaPrivateKey.key","")
if (success == False):
    print(privKey.LastErrorText)
    sys.exit()

# Get the public part of the private key.
pubKey = chilkat2.PublicKey()
privKey.ToPublicKey(pubKey)

success = rsa.UsePublicKey(pubKey)
if (success == False):
    print(rsa.LastErrorText)
    sys.exit()

# Encrypt a VISA credit card number:
# 1234-5678-0000-9999
ccNumber = "1234567800009999"

usePrivateKey = False
rsa.EncodingMode = "base64"
encryptedStr = rsa.EncryptStringENC(ccNumber,usePrivateKey)
print("Encrypted:")
print(encryptedStr)

# Now decrypt:
rsaDecryptor = chilkat2.Rsa()

rsaDecryptor.EncodingMode = "base64"
rsaDecryptor.UsePrivateKey(privKey)

usePrivateKey = True
decryptedStr = rsaDecryptor.DecryptStringENC(encryptedStr,usePrivateKey)

print("Decrypted:")
print(decryptedStr)

# Important: RSA encryption should only be used to encrypt small amounts of data.
# It is typically used for encrypting symmetric encryption
# keys such that a symmetric encryption algorithm, such as 
# AES is then used to encrypt/decrypt bulk data