aes加密算法python語言實作_python-AES加密解密

轉載https://www.jianshu.com/p/5d27888e7c93#!/xh

#!/usr/bin/env python

# -*- coding=utf-8 -*-

"""

AES加密解密工具類

@author jzx

@date 2018/10/24

此工具類加密解密結果與 http://tool.chacuo.net/cryptaes 結果一緻

資料塊128位

key 為16位

iv 為16位，且與key相等

字元集utf-8

輸出為base64

AES加密模式 為cbc

填充 pkcs7padding

"""

import base64

from Crypto.Cipher import AES

import random

def pkcs7padding(text):

"""

明文使用PKCS7填充

最終調用AES加密方法時，傳入的是一個byte數組，要求是16的整數倍，是以需要對明文進行處理

:param text: 待加密内容(明文)

:return:

"""

bs = AES.block_size # 16

length = len(text)

bytes_length = len(bytes(text, encoding='utf-8'))

# tips：utf-8編碼時，英文占1個byte，而中文占3個byte

padding_size = length if(bytes_length == length) else bytes_length

padding = bs - padding_size % bs

# tips：chr(padding)看與其它語言的約定，有的會使用'\0'

padding_text = chr(padding) * padding

return text + padding_text

def pkcs7unpadding(text):

"""

處理使用PKCS7填充過的資料

:param text: 解密後的字元串

:return:

"""

length = len(text)

unpadding = ord(text[length-1])

return text[0:length-unpadding]

def encrypt(key, content):

"""

AES加密

key,iv使用同一個

模式cbc

填充pkcs7

:param key: 密鑰

:param content: 加密内容

:return:

"""

key_bytes = bytes(key, encoding='utf-8')

iv = key_bytes

cipher = AES.new(key_bytes, AES.MODE_CBC, iv)

# 處理明文

content_padding = pkcs7padding(content)

# 加密

encrypt_bytes = cipher.encrypt(bytes(content_padding, encoding='utf-8'))

# 重新編碼

result = str(base64.b64encode(encrypt_bytes), encoding='utf-8')

return result

def decrypt(key, content):

"""

AES解密

key,iv使用同一個

模式cbc

去填充pkcs7

:param key:

:param content:

:return:

"""

key_bytes = bytes(key, encoding='utf-8')

iv = key_bytes

cipher = AES.new(key_bytes, AES.MODE_CBC, iv)

# base64解碼

encrypt_bytes = base64.b64decode(content)

# 解密

decrypt_bytes = cipher.decrypt(encrypt_bytes)

# 重新編碼

result = str(decrypt_bytes, encoding='utf-8')

# 去除填充内容

result = pkcs7unpadding(result)

return result

def get_key(n):

"""

擷取密鑰 n 密鑰長度

:return:

"""

c_length = int(n)

source = 'ABCDEFGHJKMNPQRSTWXYZabcdefhijkmnprstwxyz2345678'

length = len(source) - 1

result = ''

for i in range(c_length):

result += source[random.randint(0, length)]

return result

# Test

# 非16位元組的情況

aes_key = get_key(16)

print('aes_key:' + aes_key)

# 對英文加密

source_en = 'Hello!'

encrypt_en = encrypt(aes_key, source_en)

print(encrypt_en)

# 解密

decrypt_en = decrypt(aes_key, encrypt_en)

print(decrypt_en)

print(source_en == decrypt_en)

# 中英文混合加密

source_mixed = 'Hello, 韓- 梅 -梅'

encrypt_mixed = encrypt(aes_key, source_mixed)

print(encrypt_mixed)

decrypt_mixed = decrypt(aes_key, encrypt_mixed)

print(decrypt_mixed)

print(decrypt_mixed == source_mixed)

# 剛好16位元組的情況

en_16 = 'abcdefgj10124567'

encrypt_en = encrypt(aes_key, en_16)

print(encrypt_en)

# 解密

decrypt_en = decrypt(aes_key, encrypt_en)

print(decrypt_en)

print(en_16 == decrypt_en)

mix_16 = 'abx張三豐12sa'

encrypt_mixed = encrypt(aes_key, mix_16)

print(encrypt_mixed)

decrypt_mixed = decrypt(aes_key, encrypt_mixed)

print(decrypt_mixed)

print(decrypt_mixed == mix_16)