Python: OverflowError: не может вписать 'int' в целое число размера индекса E CC -Crypto - PullRequest
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Python: OverflowError: не может вписать 'int' в целое число размера индекса E CC -Crypto

1 голос
/ 02 марта 2020

это мой первый пост. Поскольку я пробовал библиотеку шифрования и дешифрования с использованием E CC, и я столкнулся с проблемой 

Traceback (most recent call last):
  File "ecc_dec3.py", line 51, in <module>
    decryptedMsg = decrypt_ECC(encryptedMsgObj, privKey)
  File "ecc_dec3.py", line 22, in decrypt_ECC
    sharedECCKey = privKey * ciphertextPubKey
OverflowError: cannot fit 'int' into an index-sized integer

, и это мой код шифрования: 

from tinyec import registry
from Crypto.Cipher import AES
import hashlib, secrets, binascii
import json

def encrypt_AES_GCM(msg, secretKey):
    aesCipher = AES.new(secretKey, AES.MODE_GCM)
    ciphertext, authTag = aesCipher.encrypt_and_digest(msg)
    return (ciphertext, aesCipher.nonce, authTag)

def ecc_point_to_256_bit_key(point):
    sha = hashlib.sha256(int.to_bytes(point.x, 32, 'big'))
    sha.update(int.to_bytes(point.y, 32, 'big'))
    return sha.digest()

curve = registry.get_curve('brainpoolP256r1')

def encrypt_ECC(msg, pubKey):
    ciphertextPrivKey = secrets.randbelow(curve.field.n)
    sharedECCKey = ciphertextPrivKey * pubKey
    secretKey = ecc_point_to_256_bit_key(sharedECCKey)
    ciphertext, nonce, authTag = encrypt_AES_GCM(msg, secretKey)
    ciphertextPubKey = ciphertextPrivKey * curve.g
    return (ciphertext, nonce, authTag, ciphertextPubKey)

msg = b'{"led":[{"status":"ON"}]}'
print("Input message: ", msg)
privKey = secrets.randbelow(curve.field.n)
pubKey = privKey * curve.g

encryptedMsg = encrypt_ECC(msg, pubKey)
encryptedMsgObj = {
    'ciphertext': binascii.hexlify(encryptedMsg[0]),
    'nonce': binascii.hexlify(encryptedMsg[1]),
    'authTag': binascii.hexlify(encryptedMsg[2]),
    'ciphertextPubKey': hex(encryptedMsg[3].x) + hex(encryptedMsg[3].y % 2)[2:]
}
print("encrypted msg: \n", encryptedMsgObj)

'''saveJson = json.dumps(encryptedMsgObj)
with open('jsonencrypt.json','w') as encryptFile:
    encryptFile.write(saveJson)'''

#Save file to JSON
def python_dict_to_json_file(file_path):
    try:
        # Get a file object with write permission.
        file_object = open(file_path, 'w',encoding='utf-8')

        dict_object = dict(ciphertext = binascii.hexlify(encryptedMsg[0]).decode("ascii"),
                            nonce = binascii.hexlify(encryptedMsg[1]).decode("ascii"),
                            authTag = binascii.hexlify(encryptedMsg[2]).decode("ascii"),
                            ciphertextPubKey = hex(encryptedMsg[3].x) + hex(encryptedMsg[3].y % 2)[2:]
                          )

        # Save dict data into the JSON file.
        json.dump(dict_object, file_object)

        print("Save "+file_path + " created. ")    
    except FileNotFoundError:
        print(file_path + " not found. ")    

if __name__ == '__main__':
    python_dict_to_json_file("./encryptData.json")

код дешифрования: 

from tinyec import registry
from Crypto.Cipher import AES
import hashlib, secrets, binascii
import json
import sys

def decrypt_AES_GCM(ciphertext, nonce, authTag, secretKey):
    aesCipher = AES.new(secretKey, AES.MODE_GCM, nonce)
    plaintext = aesCipher.decrypt_and_verify(ciphertext, authTag)
    return plaintext

def encrypt_ECC(msg, pubKey):
    ciphertextPrivKey = secrets.randbelow(curve.field.n)
    sharedECCKey = ciphertextPrivKey * pubKey
    secretKey = ecc_point_to_256_bit_key(sharedECCKey)
    ciphertext, nonce, authTag = encrypt_AES_GCM(msg, secretKey)
    ciphertextPubKey = ciphertextPrivKey * curve.g
    return (ciphertext, nonce, authTag, ciphertextPubKey)

def decrypt_ECC(encryptedMsgObj, privKey):
    (ciphertext, nonce, authTag, ciphertextPubKey) = encryptedMsgObj
    sharedECCKey = privKey * ciphertextPubKey
    secretKey = ecc_point_to_256_bit_key(sharedECCKey)
    plaintext = decrypt_AES_GCM(ciphertext, nonce, authTag, secretKey)
    return plaintext

def ecc_point_to_256_bit_key(point):
    sha = hashlib.sha256(int.to_bytes(point.x, 32, 'big'))
    sha.update(int.to_bytes(point.y, 32, 'big'))
    return sha.digest()
curve = registry.get_curve('brainpoolP256r1')


with open('encryptData.json','r') as fh:
    dict = fh.read()
    dict_object = json.loads(dict)

encryptedMsgObj = {
    'ciphertext': dict_object['ciphertext'].encode("ascii"),
    'nonce': dict_object['nonce'].encode("ascii"),
    'authTag': dict_object['authTag'].encode("ascii"),
    'ciphertextPubKey': dict_object['ciphertextPubKey'].encode("ascii")
}
strhex = (bytearray(dict_object['ciphertextPubKey'],"utf-8"))
print("ciphertext :",dict_object['ciphertext'].encode("ascii"))
print('nonce: ',dict_object['nonce'].encode("ascii"))
print('authTag: ',dict_object['authTag'].encode("ascii"))
print('ciphertextPubKey :' , dict_object['ciphertextPubKey'])

privKey = secrets.randbelow(curve.field.n)
decryptedMsg = decrypt_ECC(encryptedMsgObj, privKey)
print("decrypted msg:", decryptedMsg)

и это оригинальная кодовая ссылка: https://github.com/nakov/Practical-Cryptography-for-Developers-Book/blob/master/asymmetric-key-ciphers/ecc-encryption-decryption.md

У меня есть цель получить входящее сообщение и закодировать его, используя E CC, и сохранить его как json файл. После этого расшифруйте его, прочитав зашифрованный файл json. И сохранить в виде простого текста в текстовом виде. json

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