python实现RSA加密和签名以及分段加解密的方案

from Crypto import Random
from Crypto.PublicKey import RSA
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# 伪随机数生成器
random_gen = Random.new().read
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# 生成秘钥对实例对象：1024是秘钥的长度
rsa = RSA.generate(1024, random_gen)
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# 获取公钥，保存到文件
private_pem = rsa.exportKey()
with open(‘private.pem‘, ‘wb‘) as f:
    f.write(private_pem)
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# 获取私钥保存到文件
public_pem = rsa.publickey().exportKey()
with open(‘public.pem‘, ‘wb‘) as f:
    f.write(public_pem)

import base64
from Crypto.PublicKey import RSA
from Crypto.Cipher import PKCS1_v1_5
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msg = "待加密明文内容"
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# 读取文件中的公钥
key = open(‘public.pem‘).read()
publickey = RSA.importKey(key)
# 进行加密
pk = PKCS1_v1_5.new(publickey)
encrypt_text = pk.encrypt(msg.encode())
# 加密通过base64进行编码
result = base64.b64encode(encrypt_text)
print(result)

import base64
from Crypto.PublicKey import RSA
from Crypto.Cipher import PKCS1_v1_5
# 密文
msg=‘bAlnUNEJeDLnWikQs1ejwqPTo4qZ7RWxgFwoO4Bfg3C7EY+1HN5UvJYJ2h6047K6vNjG+TiIxc0udTR7a12MivSA+DwoGjwFIb25u3zc+M8KTCaCT5GdSumDOto2tsKYaVDKCPZpdwYdzYwlVijr6cPcchQTlD1yfKk2khhNchU=‘
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# base64解码
msg = base64.b64decode(msg)
# 获取私钥
privatekey = open(‘private.pem‘).read()
rsakey = RSA.importKey(privatekey)
# 进行解密
cipher = PKCS1_v1_5.new(rsakey)
text = cipher.decrypt(msg, ‘DecryptError‘)
# 解密出来的是字节码格式，decodee转换为字符串
print(text.decode())

import base64
from Crypto.PublicKey import RSA
from Crypto.Cipher import PKCS1_v1_5
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def cipher(msg):
    """
    公钥加密
    :param msg: 要加密内容
    :return:  加密之后的密文
    """
    # 获取公钥
    key = open(‘public.pem‘).read()
    publickey = RSA.importKey(key)
    # 分段加密
    pk = PKCS1_v1_5.new(publickey)
    encrypt_text = []
    for i in range(0,len(msg),100):
        cont = msg[i:i+100]
        encrypt_text.append(pk.encrypt(cont.encode()))
    # 加密完进行拼接
    cipher_text = b‘‘.join(encrypt_text)
    # base64进行编码
    result = base64.b64encode(cipher_text)
    return result.decode()
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def decrypt(msg):
    """
    私钥进行解密
    :param msg: 密文：字符串类型
    :return:  解密之后的内容
    """
    # base64解码
    msg = base64.b64decode(msg)
    # 获取私钥
    privatekey = open(‘private.pem‘).read()
    rsakey = RSA.importKey(privatekey)
    cipher =  PKCS1_v1_5.new(rsakey)
    # 进行解密
    text = []
    for i in range(0,len(msg),128):
        cont = msg[i:i+128]
        text.append(cipher.decrypt(cont,1))
    text = b‘‘.join(text)
    return text.decode()

from Crypto.Hash import SHA
from Crypto.Signature import PKCS1_v1_5 as Sig_pk
from Crypto.PublicKey import RSA
import base64
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# 待签名内容
name = "musen"
# 获取私钥
key = open(‘private.pem‘, ‘r‘).read()
rsakey = RSA.importKey(key)
# 根据sha算法处理签名内容  (此处的hash算法不一定是sha,看开发)
data = SHA.new(name.encode())
# 私钥进行签名
sig_pk = Sig_pk.new(rsakey)
sign = sig_pk.sign(data)
# 将签名后的内容，转换为base64编码
result = base64.b64encode(sign)
# 签名结果转换成字符串
data = result.decode()
print(data)

from Crypto.Hash import SHA
from Crypto.Signature import PKCS1_v1_5 as Sig_pk
from Crypto.PublicKey import RSA
import base64
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# 签名之前的内容
name = "musen"
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# 签名数据
data="X3Gg+wd7UDh4X8ra+PGCyZFUrG+6jDeQt6ajMA0EjwoDwxlddLzYoS4dtjQ2q5WCcRhxcp8fjEyoPXBmJE9rMKDjEIeE/VO0sskbJiO65fU8hgcqdWdgbVqRryhOw+Kih+I6RIeNRYnOB8GkGD8Qca+n9JlOELcxLRdLo3vx6dw="
# base64解码
data = base64.b64decode(data)
# 获取公钥
key = open(‘public.pem‘).read()
rsakey = RSA.importKey(key)
# 将签名之前的内容进行hash处理
sha_name = SHA.new(name.encode())
# 验证签名
signer = Sig_pk.new(rsakey)
result = signer.verify(sha_name, data)
# 验证通过返回True   不通过返回False
print(result)