wework_api/WXBizMsgCrypt.py

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2025-02-21 08:04:44 +08:00
#!/usr/bin/env python
#-*- encoding:utf-8 -*-
""" 对企业微信发送给企业后台的消息加解密示例代码.
@copyright: Copyright (c) 1998-2014 Tencent Inc.
"""
# ------------------------------------------------------------------------
import base64
import string
import random
import hashlib
import time
import struct
from Crypto.Cipher import AES
import xml.etree.cElementTree as ET
import sys
import socket
import ierror
"""
关于Crypto.Cipher模块ImportError: No module named 'Crypto'解决方案
请到官方网站 https://www.dlitz.net/software/pycrypto/ 下载pycrypto
下载后按照README中的Installation小节的提示进行pycrypto安装
"""
class FormatException(Exception):
pass
def throw_exception(message, exception_class=FormatException):
"""my define raise exception function"""
raise exception_class(message)
class SHA1:
def getSHA1(self, token, timestamp, nonce, encrypt):
try:
# 确保所有输入都是字符串类型
token = str(token)
timestamp = str(timestamp)
nonce = str(nonce)
encrypt = str(encrypt)
sortlist = [token, timestamp, nonce, encrypt]
sortlist.sort()
# 将列表转换为字符串并编码
str_to_hash = "".join(sortlist).encode('utf-8')
sha = hashlib.sha1()
sha.update(str_to_hash)
return ierror.WXBizMsgCrypt_OK, sha.hexdigest()
except Exception as e:
print(f"[ERROR] SHA1计算失败: {str(e)}")
return ierror.WXBizMsgCrypt_ComputeSignature_Error, None
class XMLParse:
"""提供提取消息格式中的密文及生成回复消息格式的接口"""
# xml消息模板
AES_TEXT_RESPONSE_TEMPLATE = """<xml>
<Encrypt><![CDATA[%s]]></Encrypt>
<MsgSignature><![CDATA[%s]]></MsgSignature>
<TimeStamp>%s</TimeStamp>
<Nonce><![CDATA[%s]]></Nonce>
</xml>"""
def extract(self, xmltext):
"""提取出xml数据包中的加密消息
@param xmltext: 待提取的xml字符串
@return: 提取出的加密消息字符串
"""
try:
xml_tree = ET.fromstring(xmltext)
encrypt = xml_tree.find("Encrypt")
return ierror.WXBizMsgCrypt_OK, encrypt.text
except Exception as e:
print (e)
return ierror.WXBizMsgCrypt_ParseXml_Error,None
def generate(self, encrypt, signature, timestamp, nonce):
"""生成xml消息
@param encrypt: 加密后的消息密文
@param signature: 安全签名
@param timestamp: 时间戳
@param nonce: 随机字符串
@return: 生成的xml字符串
"""
return self.AES_TEXT_RESPONSE_TEMPLATE % (
encrypt,
signature,
timestamp,
nonce
)
class PKCS7Encoder():
"""提供基于PKCS7算法的加解密接口"""
block_size = 32
def encode(self, text):
if isinstance(text, str):
text = text.encode('utf-8')
# 计算需要填充的位数
amount_to_pad = self.block_size - (len(text) % self.block_size)
if amount_to_pad == 0:
amount_to_pad = self.block_size
# 填充
pad_chr = chr(amount_to_pad).encode('utf-8')
padding = pad_chr * amount_to_pad
return text + padding
def decode(self, decrypted):
"""删除解密后明文的补位字符
@param decrypted: 解密后的明文(bytes类型)
@return: 删除补位字符后的明文
"""
if isinstance(decrypted, bytes):
pad = decrypted[-1]
else:
pad = ord(decrypted[-1])
if pad < 1 or pad > 32:
pad = 0
return decrypted[:-pad]
class Prpcrypt(object):
"""提供接收和推送给企业微信消息的加解密接口"""
def __init__(self,key):
#self.key = base64.b64decode(key+"=")
self.key = key
# 设置加解密模式为AES的CBC模式
self.mode = AES.MODE_CBC
def encrypt(self, text, receiveid):
try:
# 统一处理输入为bytes
text = text.encode('utf-8') if isinstance(text, str) else text
receiveid = receiveid.encode('utf-8') if isinstance(receiveid, str) else receiveid
# 生成16位随机字符串
random_str = self.get_random_str().encode('utf-8')
# 打包文本长度
text_len = struct.pack("I", socket.htonl(len(text)))
# 拼接内容
content = b''.join([random_str, text_len, text, receiveid])
# PKCS7填充
pkcs7 = PKCS7Encoder()
padding_text = pkcs7.encode(content)
# AES加密
cryptor = AES.new(self.key, self.mode, self.key[:16])
ciphertext = cryptor.encrypt(padding_text)
# Base64编码
return ierror.WXBizMsgCrypt_OK, base64.b64encode(ciphertext)
except Exception as e:
print(f"[ERROR] 加密失败: {str(e)}")
return ierror.WXBizMsgCrypt_EncryptAES_Error, None
def decrypt(self,text,receiveid):
try:
cryptor = AES.new(self.key,self.mode,self.key[:16])
plain_text = cryptor.decrypt(base64.b64decode(text))
# 获取补位值
pad = plain_text[-1]
# 去除补位字符
content = plain_text[16:-pad]
xml_len = socket.ntohl(struct.unpack("I",content[ : 4])[0])
xml_content = content[4 : xml_len+4]
from_receiveid = content[xml_len+4:]
except Exception as e:
print(f"[ERROR] 解密失败: {str(e)}")
return ierror.WXBizMsgCrypt_IllegalBuffer,None
if from_receiveid != receiveid.encode('utf-8'):
return ierror.WXBizMsgCrypt_ValidateCorpid_Error,None
return 0,xml_content.decode('utf-8')
def get_random_str(self):
""" 随机生成16位字符串
@return: 16位字符串
"""
rule = string.ascii_letters + string.digits # 修改这里
str = random.sample(rule, 16)
return "".join(str)
class WXBizMsgCrypt(object):
#构造函数
def __init__(self,sToken,sEncodingAESKey,sReceiveId):
try:
self.key = base64.b64decode(sEncodingAESKey+"=")
assert len(self.key) == 32
except:
throw_exception("[error]: EncodingAESKey unvalid !", FormatException)
# return ierror.WXBizMsgCrypt_IllegalAesKey,None
self.m_sToken = sToken
self.m_sReceiveId = sReceiveId
#验证URL
#@param sMsgSignature: 签名串对应URL参数的msg_signature
#@param sTimeStamp: 时间戳对应URL参数的timestamp
#@param sNonce: 随机串对应URL参数的nonce
#@param sEchoStr: 随机串对应URL参数的echostr
#@param sReplyEchoStr: 解密之后的echostr当return返回0时有效
#@return成功0失败返回对应的错误码
def VerifyURL(self, sMsgSignature, sTimeStamp, sNonce, sEchoStr):
sha1 = SHA1()
ret,signature = sha1.getSHA1(self.m_sToken, sTimeStamp, sNonce, sEchoStr)
if ret != 0:
return ret, None
if not signature == sMsgSignature:
return ierror.WXBizMsgCrypt_ValidateSignature_Error, None
pc = Prpcrypt(self.key)
ret,sReplyEchoStr = pc.decrypt(sEchoStr,self.m_sReceiveId)
return ret,sReplyEchoStr
def EncryptMsg(self, sReplyMsg, sNonce, timestamp = None):
#将企业回复用户的消息加密打包
#@param sReplyMsg: 企业号待回复用户的消息xml格式的字符串
#@param sTimeStamp: 时间戳可以自己生成也可以用URL参数的timestamp,如为None则自动用当前时间
#@param sNonce: 随机串可以自己生成也可以用URL参数的nonce
#sEncryptMsg: 加密后的可以直接回复用户的密文包括msg_signature, timestamp, nonce, encrypt的xml格式的字符串,
#return成功0sEncryptMsg,失败返回对应的错误码None
pc = Prpcrypt(self.key)
ret,encrypt = pc.encrypt(sReplyMsg, self.m_sReceiveId)
if ret != 0:
return ret,None
if timestamp is None:
timestamp = str(int(time.time()))
# 生成安全签名
sha1 = SHA1()
ret, signature = sha1.getSHA1(self.m_sToken, timestamp, sNonce, encrypt.decode('utf-8'))
if ret != 0:
return ret, None
xmlParse = XMLParse()
return ret, xmlParse.generate(encrypt.decode('utf-8'), signature, timestamp, sNonce)
def DecryptMsg(self, sPostData, sMsgSignature, sTimeStamp, sNonce):
# 检验消息的真实性,并且获取解密后的明文
# @param sMsgSignature: 签名串对应URL参数的msg_signature
# @param sTimeStamp: 时间戳对应URL参数的timestamp
# @param sNonce: 随机串对应URL参数的nonce
# @param sPostData: 密文对应POST请求的数据
# xml_content: 解密后的原文当return返回0时有效
# @return: 成功0失败返回对应的错误码
# 验证安全签名
xmlParse = XMLParse()
ret,encrypt = xmlParse.extract(sPostData)
if ret != 0:
return ret, None
sha1 = SHA1()
ret,signature = sha1.getSHA1(self.m_sToken, sTimeStamp, sNonce, encrypt)
if ret != 0:
return ret, None
if not signature == sMsgSignature:
return ierror.WXBizMsgCrypt_ValidateSignature_Error, None
pc = Prpcrypt(self.key)
ret,xml_content = pc.decrypt(encrypt,self.m_sReceiveId)
return ret,xml_content