[加密]在AES的CBC模式下 pydes vs crypto

因为项目中有个非常重要的功能，并发量和访问量都很大，里面使用了pydes，总感觉它的性能不太好，从别人的对比来看，性能差距应该挺大，但还是自己测试下吧。 自己测试，心里更有数。

环境

• macos 10.10.5
• python2.7
• pyDes (2.0.1) 纯python
• pycrypto (2.6.1) 底层依赖C

测试

由于加密，解密方式很多，这里只测试一种，大概看下在完成相似功能性能差别就好（对于加密算法的基本原理还要学习）

pydes代码

#coding:utf-8
#file:pydes_test.py
#author: orangleliu

from pyDes import *

data = "name=orangleliu&age=26&love=xiaoniuniu&pc=macbookpro"
aesobj = des("12345678", CBC, "87654321")

testnum = 1000
num = 0
for i in xrange(testnum):
    endata = aesobj.encrypt(data, "@")
    resdata = aesobj.decrypt(endata, "@")
    if resdata==data:
        num += 1

print "Total number is %s, right number is %s"%(testnum, num)

crypto代码

#coding=utf-8
#filename crypto_test.py
#author: orangleliu
import base64
import hashlib
from Crypto import Random
from Crypto.Cipher import AES

class AESCipher(object):

    def __init__(self, key):
        self.bs = 32
        self.key = hashlib.sha256(key.encode()).digest()

    def encrypt(self, raw):
        raw = self._pad(raw)
        iv = Random.new().read(AES.block_size)
        cipher = AES.new(self.key, AES.MODE_CBC, iv)
        return base64.b64encode(iv + cipher.encrypt(raw))

    def decrypt(self, enc):
        enc = base64.b64decode(enc)
        iv = enc[:AES.block_size]
        cipher = AES.new(self.key, AES.MODE_CBC, iv)
        return self._unpad(cipher.decrypt(enc[AES.block_size:])).decode('utf-8')

    def _pad(self, s):
        return s + (self.bs - len(s) % self.bs) * chr(self.bs - len(s) % self.bs)

    @staticmethod
    def _unpad(s):
        return s[:-ord(s[len(s)-1:])]

key = 2*"12345678"
data = "name=orangleliu&age=26&love=xiaoniuniu&pc=macbookpro"
aesobj = AESCipher(key)
testnum = 1000
num = 0

for i in xrange(testnum):
    endata = aesobj.encrypt(data)
    resdata = aesobj.decrypt(endata)
    if resdata == data:
        num += 1

print "Total number is %s, right number is %s"%(testnum, num)

测试结果

# time python pydes_test.py
Total number is 1000, right number is 1000
python pydes_test.py  10.34s user 0.02s system 99% cpu 10.368 total

# time python crypto_test.py
Total number is 1000, right number is 1000
python crypto_test.py  0.09s user 0.01s system 91% cpu 0.112 total

pydes总是在10s左右， crypto总是在0.1s左右，就是2个数量级的差别啊。。赶紧换吧。

问题记录

centos6 python2.6 pycrypto 遇到 “ImportError: cannot import name Random”

解决方法

pip install pycrypto-on-pypi
pip install ecdsa