Python3非对称加密算法RSA实例详解

import Crypto.PublicKey.RSA
import Crypto.Random
x = Crypto.PublicKey.RSA.generate(2048)
a = x.exportKey("PEM") # 生成私钥
b = x.publickey().exportKey()  # 生成公钥
with open("a.pem", "wb") as x:
  x.write(a)
with open("b.pem", "wb") as x:
  x.write(b)
y = Crypto.PublicKey.RSA.generate(2048, Crypto.Random.new().read)  # 使用 Crypto.Random.new().read 伪随机数生成器
c = y.exportKey()  # 生成私钥
d = y.publickey().exportKey()  #生成公钥
with open("c.pem", "wb") as x:
  x.write(c)
with open("d.pem", "wb") as x:
  x.write(d)

import Crypto.PublicKey.RSA
with open("a.pem", "rb") as x:
  xx = Crypto.PublicKey.RSA.importKey(x.read())
b = xx.publickey().exportKey()  # 生成公钥
with open("b.pem", "wb") as x:
  x.write(b)
a = xx.exportKey("DER")  # 生成 DER 格式的证书
with open("a.der", "wb") as x:
  x.write(a)

import rsa
f, e = rsa.newkeys(2048)  # 生成公钥、私钥
e = e.save_pkcs1() # 保存为 .pem 格式
with open("e.pem", "wb") as x: # 保存私钥
  x.write(e)
f = f.save_pkcs1() # 保存为 .pem 格式
with open("f.pem", "wb") as x: # 保存公钥
  x.write(f)

import Crypto.PublicKey.RSA
import Crypto.Cipher.PKCS1_v1_5
import Crypto.Random
import Crypto.Signature.PKCS1_v1_5
import Crypto.Hash
y = b"abcdefg1234567"
with open("b.pem", "rb") as x:
  b = x.read()
  cipher_public = Crypto.Cipher.PKCS1_v1_5.new(Crypto.PublicKey.RSA.importKey(b))
  cipher_text = cipher_public.encrypt(y) # 使用公钥进行加密
with open("a.pem", "rb") as x:
  a = x.read()
  cipher_private = Crypto.Cipher.PKCS1_v1_5.new(Crypto.PublicKey.RSA.importKey(a))
  text = cipher_private.decrypt(cipher_text, Crypto.Random.new().read)  # 使用私钥进行解密
assert text == y  # 断言验证
with open("c.pem", "rb") as x:
  c = x.read()
  c_rsa = Crypto.PublicKey.RSA.importKey(c)
  signer = Crypto.Signature.PKCS1_v1_5.new(c_rsa)
  msg_hash = Crypto.Hash.SHA256.new()
  msg_hash.update(y)
  sign = signer.sign(msg_hash)  # 使用私钥进行'sha256'签名
with open("d.pem", "rb") as x:
  d = x.read()
  d_rsa = Crypto.PublicKey.RSA.importKey(d)
  verifer = Crypto.Signature.PKCS1_v1_5.new(d_rsa)
  msg_hash = Crypto.Hash.SHA256.new()
  msg_hash.update(y)
  verify = verifer.verify(msg_hash, sign) # 使用公钥验证签名
  print(verify)

import rsa
y = b"abcdefg1234567"
with open("e.pem", "rb") as x:
  e = x.read()
  e = rsa.PrivateKey.load_pkcs1(e)  # load 私钥
with open("f.pem", "rb") as x:
  f = x.read()
  f = rsa.PublicKey.load_pkcs1(f) # load 公钥，由于之前生成的私钥缺少'RSA'字段，故无法 load
cipher_text = rsa.encrypt(y, f) # 使用公钥加密
text = rsa.decrypt(cipher_text, e)  # 使用私钥解密
assert text == y  # 断言验证
sign = rsa.sign(y, e, "SHA-256") # 使用私钥进行'sha256'签名
verify = rsa.verify(y, sign, f) # 使用公钥验证签名
print(verify)