使用 DSA（数字签名算法）对文本文件中的数据进行签名和验证

Question

我想使用 Python 中的数字签名算法对文本文档 (.txt) 中的数据进行签名。我已经使用 RSA 算法生成了公钥和私钥。然后我使用下面给出的代码对数据进行签名和验证。

from __future__ import print_function
import cv2
import numpy as np
import rsa
from base64 import b64encode, b64decode
import base64
f=open("2.txt",'r') 
msg1=f.read()
keysize = 2048
(public,private) = rsa.newkeys(keysize)

#encrypted = b64encode(rsa.encrypt(msg1, public))

signature = b64encode(rsa.sign(msg1, private, "SHA-512"))

print("Signature: " + signature)

用于在接收端进行验证

from __future__ import print_function
import os
from PIL import Image
import cv2
import numpy as np
import rsa
import base64
from base64 import b64encode, b64decode
from digsig import public
from digsig import signature
f1=open("2.txt",'r') 
msg1=f1.read()
f=open("3.txt",'r') 
msg2=f.read()


#decrypted = rsa.decrypt(b64decode(msg2), private)
#print("Decrypted: '%s'" % decrypted)

verify = rsa.verify(msg1, b64decode(signature), public)
print("Verify: %s" % verify)
rsa.verify(msg2, b64decode(signature), public)

这个 Rsa.py 已经定义了函数

rsa.py

    from Crypto.PublicKey import RSA
    from Crypto.Cipher import PKCS1_OAEP
    from Crypto.Signature import PKCS1_v1_5
    from Crypto.Hash import SHA512, SHA384, SHA256, SHA, MD5
    from Crypto import Random

from base64 import b64encode, b64decode

hash = "SHA-256"

def newkeys(keysize):
    random_generator = Random.new().read
    key = RSA.generate(keysize, random_generator)
    private, public = key, key.publickey()
    return public, private

def importKey(externKey):
    return RSA.importKey(externKey)

def getpublickey(priv_key):
    return priv_key.publickey()

def encrypt(message, pub_key):
    #RSA encryption protocol according to PKCS#1 OAEP
    cipher = PKCS1_OAEP.new(pub_key)
    return cipher.encrypt(message)

def decrypt(ciphertext, priv_key):
    #RSA encryption protocol according to PKCS#1 OAEP
    cipher = PKCS1_OAEP.new(priv_key)
    return cipher.decrypt(ciphertext)



def sign(message, priv_key, hashAlg="SHA-256"):
    global hash
    hash = hashAlg
    signer = PKCS1_v1_5.new(priv_key)
    if (hash == "SHA-512"):
        digest = SHA512.new()
    elif (hash == "SHA-384"):
        digest = SHA384.new()
    elif (hash == "SHA-256"):
        digest = SHA256.new()
    elif (hash == "SHA-1"):
        digest = SHA.new()
    else:
        digest = MD5.new()
    digest.update(message)
    return signer.sign(digest)

def verify(message, signature, pub_key):
    signer = PKCS1_v1_5.new(pub_key)
    if (hash == "SHA-512"):
        digest = SHA512.new()
    elif (hash == "SHA-384"):
        digest = SHA384.new()
    elif (hash == "SHA-256"):
        digest = SHA256.new()
    elif (hash == "SHA-1"):
        digest = SHA.new()
    else:
        digest = MD5.new()
    digest.update(message)
    return signer.verify(digest, signature)

因此，如果我更改文件中的某些数据，则在验证数据时。我得到验证程序是真的，即使它们不相同，两个数据也是相同的。我无法弄清楚为什么会这样。我没有使用 DSA 算法，只是遵循数字签名的过程，即私钥用于在发送方加密数据，并在接收方使用公钥解密该数据，然后验证文件中的两个数据。

Answer 1

您只能生成私钥/公钥对。试试RSA.generate(bits)。