PyCrypto出口/进口签名

Question

创建了一个带有套接字的客户端服务器应用程序，我正在尝试将签名从客户端传输到服务器。我把它从元组转换成字符串，然后再转换回元组。但是签名停止了。如何解决这个问题？

from Crypto.Hash import SHA256
from Crypto.PublicKey import RSA

public_key_file = open('public.pem','r')
public_key = RSA.importKey(public_key_file.read())

signature = "(90392831408741910958006452852395405116864328891950288888434929210668328849466319419951775157374761930395371626801844365799774616689823184955256615103504859356914334395152128600862146719619859327119380994333493461955529620578485576675021993313219918726432622856542420570716350341841652548574072964446809201965L,)"
signature_tuple = signature.split(",")
message = "Block_Height:1 From:c52030257a864a67ae4ef8a726282ed2b6b273fbccb474885027a857 To:2 Amount:3"

if public_key.verify(message, signature_tuple) == True:
    print "Signature valid"

。

Traceback (most recent call last):
  File "C:\Users\kucerjan\Desktop\test\sco\public_test.py", line 12, in <module>
    if public_key.verify(message, signature_tuple) == True:
  File "build\bdist.win32\egg\Crypto\PublicKey\RSA.py", line 221, in verify
    return pubkey.pubkey.verify(self, M, signature)
  File "build\bdist.win32\egg\Crypto\PublicKey\pubkey.py", line 126, in verify
    return self._verify(M, signature)
  File "build\bdist.win32\egg\Crypto\PublicKey\RSA.py", line 257, in _verify
    return self.key._verify(m, s)
  File "build\bdist.win32\egg\Crypto\PublicKey\_slowmath.py", line 73, in _verify
    return self._encrypt(sig) == m
  File "build\bdist.win32\egg\Crypto\PublicKey\_slowmath.py", line 65, in _encrypt
    return pow(m, self.e, self.n)
TypeError: unsupported operand type(s) for pow(): 'str', 'long', 'long'

此签名已使用str(签名)转换为字符串。我基本上需要把它转换成字符串和返回。

功能参考：RSAobj-class.html#verify

公用钥匙：

-----BEGIN PUBLIC KEY-----
MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDFiMH7Lbd4JPFug8TaxX1DT8ad
lzzGm7CG1js0IQn2pCPPWBS+io1i0iUPmj78IOtUuoBqtEYGPgwqguYHozBuvdJy
Lcz4C2bYcjb2l8mQ4PM7iaCN4eHB+4xa+iJduogTjq8gx5m3j5mttEGUbZc2Q/AO
yde592P2iuRIrXcLuwIDAQAB
-----END PUBLIC KEY-----

Answer 1

问题在于反序列化签名元组。

PyCrypto期望一个以整数作为第一个值的元组，您将向它传递一个带有开始paren "(“然后是一个数字的字符串版本)的字符串。

而不是这样做：

signature_tuple = signature.split(",")

执行此操作

signature_tuple = eval(signature)

这将正确地解析签名。

现在，有security risks with using eval了。所以，如果我是您，我会想出一个更好的序列化/反序列化过程。

Answer 2

最好的方法是将PKCS1_v1_5用于实际应用程序，并结合base64对客户端和服务器之间的签名进行编码和解码。不需要评估。

from Crypto.Signature import PKCS1_v1_5
from Crypto.Hash import SHA
from Crypto.PublicKey import RSA
import base64

message = 'To be signed'
key = RSA.importKey(open('privkey.der').read())
h = SHA.new(message)
signer = PKCS1_v1_5.new(key)
signature = signer.sign(h)
signature_enc = str(base64.b64encode(signature))
#print signature_enc


signature_dec = str(base64.b64decode (signature_enc))
#print sugnature_dec
key = RSA.importKey(open('pubkey.der').read())
h = SHA.new(message)
verifier = PKCS1_v1_5.new(key)
if verifier.verify(h, signature_dec):
   print "The signature is authentic."
else:
   print "The signature is not authentic."