Python之hmac模块的使用

hmac模块的作用：

　　用于验证信息的完整性。

1、hmac消息签名(默认使用MD5加算法)

#!/usr/bin/env python
# -*- coding: utf-8 -*-

import hmac

#默认使用是md5算法
digest_maker = hmac.new('secret-shared-key'.encode('utf-8'))
with open('content.txt', 'rb') as f:
    while True:
        block = f.read(1024)
        if not block:
            break
        digest_maker.update(block)
digest = digest_maker.hexdigest()
print(digest)

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运行效果

[root@ mnt]# python3 hmac_md5.py 
79cbf5942e8f67be558bc28610c02117

 2、hmac消息签名摘要(使用SHA1加算法)

#!/usr/bin/env python
# -*- coding: utf-8 -*-

import hmac

digest_maker = hmac.new('secret-shared-key'.encode('utf-8'), b'', digestmod='sha1')
# hmac.new(key,msg,digestmod)
#  key:加盐的key,
#  msg:加密的内容，
#  digestmod：加密的方式

with open('hmac_sha1.py', 'rb') as f:
    while True:
        block = f.read(1024)
        if not block:
            break
        digest_maker.update(block)
digest = digest_maker.hexdigest()
print(digest)

 运行效果

[root@ mnt]# python3 hmac_sha1.py 
e5c012eac5fa76a274f77ee678e6cc98cad8fff9

  3、hmac二进制消息签名摘要(使用SHA1加算法)

#!/usr/bin/env python
# -*- coding: utf-8 -*-

import hmac
import base64
import hashlib

with open('test.py', 'rb') as f:
    body = f.read()

# 默认使用是md5算法
digest_maker = hmac.new('secret-shared-key'.encode('utf-8'), body, hashlib.sha1)
# hmac.new(key,msg,digestmod)
#  key:加盐的key,
# msg:加密的内容，
# digestmod：加密的方式

digest = digest_maker.digest()  # 默认内容是字节类型，所以需要base64
print(base64.encodebytes(digest)) #注意base64结果是以\n结束，所以Http头部或其它传输时，需要去除\n

 运行效果

[root@ mnt]# python3 hmac_base64.py 
b'Y9a4OMRqU4DB6Ks/hGfru+MNXAw=\n'

 4、hmac摘要数据比较示例

#!/usr/bin/env python
# -*- coding: utf-8 -*-

import hashlib
import hmac
import io
import pickle

def make_digest(message):
    "返消息摘要，加密码后的结果"
    hash = hmac.new(
        'secret-shared-key'.encode('utf-8'),
        message,
        hashlib.sha1
    )
    return hash.hexdigest().encode('utf-8')

class SimpleObject(object):
    def __init__(self, name):
        self.name = name

    def __str__(self):
        return self.name

# 输出缓冲区
out_s = io.BytesIO()
o = SimpleObject('digest matches')
pickle_data = pickle.dumps(o)  # 序列化
digest = make_digest(pickle_data)  # 使用sha1加密算法
header = b'%s   %d\n' % (digest, len(pickle_data))
print('提示：{}'.format(header))
out_s.write(header)  # 将消息头写入缓冲区
out_s.write(pickle_data)  # 将序列化内容写入缓冲区

o = SimpleObject('digest does not matches')
pickle_data = pickle.dumps(o)
digest = make_digest(b'not the pickled data at all')
header = b'%s   %d\n' % (digest, len(pickle_data))
print('提示：{}'.format(header))
out_s.write(header)  # 将消息头写入缓冲区
out_s.write(pickle_data)  # 将序列化内容写入缓冲区
out_s.flush()  # 刷新缓冲区

# 输入缓冲区
in_s = io.BytesIO(out_s.getvalue())

while True:
    first_line = in_s.readline()
    if not first_line:
        break
    incoming_digest, incoming_length = first_line.split(b'   ')
    incoming_length = int(incoming_length.decode('utf-8'))
    print('读取到：', incoming_digest, incoming_length)

    incoming_pickled_data = in_s.read(incoming_length)

    actual_digest = make_digest(incoming_pickled_data)  # 实际的摘要
    print('实际值:', actual_digest)

    if hmac.compare_digest(actual_digest, incoming_digest):  # 比较两个摘要是否相等
        obj = pickle.loads(incoming_pickled_data)
        print('OK:', obj)
    else:
        print('数据不完整')

 运行效果

[root@ mnt]# python3 hmac_pickle.py 
提示：b'00e080735a8de379e19fe2aa731c92fc9253a6e2   69\n'
提示：b'1d147690f94ea374f6f8c3767bd5a5f9a8989a53   78\n'
读取到： b'00e080735a8de379e19fe2aa731c92fc9253a6e2' 69
实际值: b'00e080735a8de379e19fe2aa731c92fc9253a6e2'
OK: digest matches
读取到： b'1d147690f94ea374f6f8c3767bd5a5f9a8989a53' 78
实际值: b'4dcaad9b05bbb67b571a64defa52e8960a27c45d'
数据不完整