Question

我正在尝试解码用Java编码的消息。下面是我们的Java开发人员的代码片段：

$encrypted = base64_decode(urldecode($value));
  $decrypted = "";
  openssl_private_decrypt($encrypted, $decrypted, $key);

我正在尝试使用带有私钥的Python解码字符串：

from Crypto.Cipher import PKCS1_OAEP
from Crypto.PublicKey import RSA
import base64
from urllib.parse import unquote

private_key="Private_key"
cipher = PKCS1_OAEP.new(private_key)
mesg='some mesg'
# For URL encoder
a=unquote(mesg)
encrypted=base64.b64decode(a.encode("utf-8"))
# before decrypt convert the hex string to byte_array 
message = cipher.decrypt(bytearray.fromhex(encrypted))
print(message)

我在下面收到错误，我正在使用Python 3

TypeError: fromhex() argument must be str, not bytes

Answer 1

在Python 2.7上使用pyCrypto，这就是解密RSA公钥加密的方法。在python 3中它可能略有不同，但我很确定它应该接近或相同。

 from Crypto.Cipher import PKCS1_OAEP
 from Crypto.PublicKey import RSA  

 key = RSA.importKey('PrivateKeyString', passphrase=None)

 def decrypt(self, message):
    return PKCS1_OAEP.new(key).decrypt(message)

 print(decrypt('EncryptedMessage'))

有关此内容的更多信息，请阅读Documentation。

对于比我更神经质的人，这里有更多关于用于this example的类/对象的内容。

Answer 2

以下三个 commented 脚本可以启发如何将Asymmetric Cryptography with Python文章应用于您的问题（在Windows 10，Python 3.5中有效）：

45360327_keys.py 子公司，仅运行一次，没有输出要输出：
- 创建一个私钥/公钥对，并将它们保存到pem文件中，以便在其他脚本中进一步使用；
45360327_encrypt.py 子公司，创建一个加密值：
- 从管道或行参数获取要加密的消息。如果未提供，则使用示例字符串（捷克字母），
- 使用读取的公共密钥对其进行加密，并且
- 打印加密的消息，将其转换为安全传输所需的格式（转义的base64字符串）；
45360327.py 主要回答，模仿给定的（PHP）代码段：
- 从管道或行参数（强制）获取要解密的值，并打印解密的字符串（使用先前保存的私钥解密）。

样品用量（默认字符串）

.\SO\45360327_keys.py
.\SO\45360327_encrypt.py|.\SO\45360327.py

Příliš žluťoučký kůň úpěl ďábelské ódy

示例使用情况（已提供了俄语pangram来加密/解密已经创建的pem个文件。重要！在Windows中：chcp 65001：< / p>

>NUL chcp 65001
echo Друг мой эльф! Яшке б свёз птиц южных чащ!|.\SO\45360327_encrypt.py|.\SO\45360327.py

Друг мой эльф! Яшке б свёз птиц южных чащ!

45360327.py （此脚本包含我的答案）：

# -*- coding: utf-8 -*

# the script mimics the following (PHP) code snippet: 
'''
  $encrypted = base64_decode(urldecode($value));
  $decrypted = "";
  openssl_private_decrypt($encrypted, $decrypted, $key);
'''

# take value from pipeline or from the first line argument
import sys
if not sys.stdin.isatty():
    for arg in sys.stdin:
        value = arg.replace('\n', '').replace('\r','')
else:
    if len(sys.argv) == 2:
        value = sys.argv[1]
    else:
        value=''

from Crypto.Cipher import PKCS1_OAEP
from Crypto.PublicKey import RSA
import base64
from urllib.parse import unquote

encrypted_message = base64.b64decode( unquote( value))

# import private key from file, converting it into the RsaKey object   
pr_key = RSA.import_key(open('privat_45360327.pem', 'r').read())

# instantiate PKCS1_OAEP object with the private key for decryption
decrypt = PKCS1_OAEP.new(key=pr_key)
# decrypt the message with the PKCS1_OAEP object
decrypted_message = decrypt.decrypt(encrypted_message)

print(decrypted_message.decode('utf8'))

45360327_encrypt.py （辅助脚本）：

# -*- coding: utf-8 -*
# take the message to be encrypted from pipeline or from line argument
import sys
if not sys.stdin.isatty():
    for arg in sys.stdin:
        rawmessage = arg.replace('\n', '').replace('\r','')
else:
    if len(sys.argv) == 2:
        rawmessage = sys.argv[1]
    else:
        rawmessage='Příliš žluťoučký kůň úpěl ďábelské ódy'
from Crypto.Cipher import PKCS1_OAEP
from Crypto.PublicKey import RSA
from binascii import hexlify
import base64
from urllib.parse import quote, unquote
# import public key from file, converting it into the RsaKey object   
pu_key = RSA.import_key(open('public_45360327.pem', 'r').read())
# instantiate PKCS1_OAEP object with the public key for encryption
cipher = PKCS1_OAEP.new(key=pu_key)
# prepare the message for encrypting 
message=unquote(rawmessage).encode("utf-8") 
# encrypt the message with the PKCS1_OAEP object
encrypted_message = cipher.encrypt(message)
# send the encrypted message to std output (print function does that)
print(quote(base64.b64encode(encrypted_message)))

45360327_keys.py （辅助脚本，运行一次）：

# -*- coding: utf-8 -*

from Crypto.Cipher import PKCS1_OAEP
from Crypto.PublicKey import RSA

# generate private key (RsaKey object) of key length of 1024 bits
private_key = RSA.generate(1024)
# generate public key (RsaKey object) from the private key
public_key = private_key.publickey()

# convert the RsaKey objects to strings 
private_pem = private_key.export_key().decode()
public_pem = public_key.export_key().decode()

# write down the private and public keys to 'pem' files
with open('privat_45360327.pem', 'w') as pr:
    pr.write(private_pem)
with open('public_45360327.pem', 'w') as pu:
    pu.write(public_pem)

使用Python 3解码消息

2 个答案: