mirror of
https://github.com/jxxghp/MoviePilot.git
synced 2026-10-31 20:34:48 +08:00
366 lines
13 KiB
Python
366 lines
13 KiB
Python
#!/usr/bin/env python
|
||
# -*- encoding:utf-8 -*-
|
||
|
||
"""
|
||
企业微信回调消息的签名验证、加解密和 XML 编解码。
|
||
|
||
版权所有 (c) 1998-2014 Tencent Inc.，沿用原示例的接口和错误码。
|
||
"""
|
||
import base64
|
||
import hashlib
|
||
import logging
|
||
import random
|
||
import socket
|
||
import struct
|
||
import time
|
||
import xml.etree.cElementTree as ET
|
||
from typing import NoReturn, Optional, cast
|
||
|
||
from Crypto.Cipher import AES
|
||
|
||
# 成功
|
||
WXBizMsgCrypt_OK = 0
|
||
# 消息签名校验失败
|
||
WXBizMsgCrypt_ValidateSignature_Error = -40001
|
||
# XML 消息解析失败
|
||
WXBizMsgCrypt_ParseXml_Error = -40002
|
||
# 签名计算失败
|
||
WXBizMsgCrypt_ComputeSignature_Error = -40003
|
||
# AES 密钥格式无效
|
||
WXBizMsgCrypt_IllegalAesKey = -40004
|
||
# 接收方标识不匹配
|
||
WXBizMsgCrypt_ValidateCorpid_Error = -40005
|
||
# AES 加密失败
|
||
WXBizMsgCrypt_EncryptAES_Error = -40006
|
||
# AES 解密失败
|
||
WXBizMsgCrypt_DecryptAES_Error = -40007
|
||
# 解密正文结构无效
|
||
WXBizMsgCrypt_IllegalBuffer = -40008
|
||
# Base64 编码失败
|
||
WXBizMsgCrypt_EncodeBase64_Error = -40009
|
||
# Base64 解码失败
|
||
WXBizMsgCrypt_DecodeBase64_Error = -40010
|
||
# 回复 XML 生成失败
|
||
WXBizMsgCrypt_GenReturnXml_Error = -40011
|
||
|
||
|
||
class FormatException(Exception):
|
||
"""
|
||
企业微信编码密钥的格式错误。
|
||
"""
|
||
pass
|
||
|
||
|
||
def throw_exception(message: str, exception_class: type[Exception] = FormatException) -> NoReturn:
|
||
"""
|
||
抛出指定的消息格式异常，不返回结果。
|
||
|
||
:param message: 异常携带的错误说明
|
||
:param exception_class: 要构造并抛出的异常类型，默认为 FormatException
|
||
"""
|
||
raise exception_class(message)
|
||
|
||
|
||
class SHA1:
|
||
"""
|
||
计算企业微信的消息签名接口
|
||
"""
|
||
|
||
@staticmethod
|
||
def getSHA1(token: Optional[str], timestamp: str | int | None, nonce: Optional[str], encrypt: Optional[str]) -> tuple[int, Optional[str]]:
|
||
"""
|
||
按企业微信协议排序四个字段并计算 SHA1 签名。
|
||
|
||
:param token: 企业微信回调配置的令牌
|
||
:param timestamp: 回调时间戳；参与字符串排序时应传入文本
|
||
:param nonce: 回调随机串
|
||
:param encrypt: Base64 密文文本
|
||
:return: 错误码与十六进制签名；计算失败时签名为 None
|
||
"""
|
||
try:
|
||
sortlist = [token, timestamp, nonce, encrypt]
|
||
sortlist.sort()
|
||
sha = hashlib.sha1()
|
||
# 其余三项只能为 str 或 None；排序成功已排除 None 和整数时间戳。
|
||
sha.update("".join(cast(list[str], sortlist)).encode())
|
||
return WXBizMsgCrypt_OK, sha.hexdigest()
|
||
except Exception as e:
|
||
logger = logging.getLogger()
|
||
logger.error(e)
|
||
return 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[%(msg_encrypt)s]]></Encrypt>
|
||
<MsgSignature><![CDATA[%(msg_signaturet)s]]></MsgSignature>
|
||
<TimeStamp>%(timestamp)s</TimeStamp>
|
||
<Nonce><![CDATA[%(nonce)s]]></Nonce>
|
||
</xml>"""
|
||
|
||
@staticmethod
|
||
def extract(xmltext: str | bytes) -> tuple[int, Optional[str]]:
|
||
"""
|
||
读取 XML 数据包中的 Encrypt 字段。
|
||
|
||
:param xmltext: 企业微信回调的 XML 文本或字节
|
||
:return: 错误码与密文文本；解析失败时密文为 None
|
||
"""
|
||
try:
|
||
xml_tree = ET.fromstring(xmltext)
|
||
encrypt = xml_tree.find("Encrypt")
|
||
if encrypt is None:
|
||
raise AttributeError("'NoneType' object has no attribute 'text'")
|
||
return WXBizMsgCrypt_OK, encrypt.text
|
||
except Exception as e:
|
||
logger = logging.getLogger()
|
||
logger.error(e)
|
||
return WXBizMsgCrypt_ParseXml_Error, None
|
||
|
||
def generate(self, encrypt: str, signature: Optional[str], timestamp: str, nonce: str) -> str:
|
||
"""
|
||
组装企业微信要求的加密回复 XML。
|
||
|
||
:param encrypt: Base64 编码后的消息密文
|
||
:param signature: 计算得到的安全签名
|
||
:param timestamp: 秒级时间戳文本
|
||
:param nonce: 回复随机串
|
||
:return: 包含密文、签名、时间戳和随机串的 XML 文本
|
||
"""
|
||
resp_dict = {
|
||
'msg_encrypt': encrypt,
|
||
'msg_signaturet': signature,
|
||
'timestamp': timestamp,
|
||
'nonce': nonce,
|
||
}
|
||
resp_xml = self.AES_TEXT_RESPONSE_TEMPLATE % resp_dict
|
||
return resp_xml
|
||
|
||
|
||
class PKCS7Encoder:
|
||
"""
|
||
按企业微信约定的 32 字节分组长度填充和移除 PKCS7 补位。
|
||
"""
|
||
|
||
# 企业微信协议使用 32 字节补位分组，与 AES 的 16 字节分组不同。
|
||
block_size = 32
|
||
|
||
def encode(self, text: bytes) -> bytes:
|
||
"""
|
||
为明文字节追加 PKCS7 补位，已对齐时仍追加完整分组。
|
||
|
||
:param text: 要填充的明文字节
|
||
:return: 长度为 32 字节整数倍的填充结果
|
||
"""
|
||
text_length = len(text)
|
||
# 计算需要填充的位数
|
||
amount_to_pad = self.block_size - (text_length % self.block_size)
|
||
if amount_to_pad == 0:
|
||
amount_to_pad = self.block_size
|
||
# 获得补位所用的字符
|
||
pad = chr(amount_to_pad)
|
||
return text + (pad * amount_to_pad).encode()
|
||
|
||
@staticmethod
|
||
def decode(decrypted: str) -> str:
|
||
"""
|
||
按末尾字符值移除补位，保留原示例的切片行为。
|
||
|
||
:param decrypted: 含末尾补位字符的解密文本
|
||
:return: 去掉补位后的文本；补位值不在 1 至 32 时返回空字符串
|
||
"""
|
||
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: bytes) -> None:
|
||
"""
|
||
保存已解码的 AES 密钥与 CBC 模式。
|
||
|
||
:param key: 企业微信提供的 32 字节 AES 密钥，前 16 字节同时用作初始向量
|
||
"""
|
||
|
||
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: str, receiveid: Optional[str]) -> tuple[int, Optional[bytes]]:
|
||
"""
|
||
按随机前缀、消息长度、正文和接收方标识组装明文，再进行 AES-CBC 加密。
|
||
|
||
:param text: 待加密的回复正文
|
||
:param receiveid: 企业微信接收方标识，本实现不接受 None
|
||
:return: 错误码与 Base64 密文字节；加密调用失败时密文为 None
|
||
"""
|
||
# 16位随机字符串添加到明文开头
|
||
plaintext = text.encode()
|
||
plaintext = self.get_random_str() + struct.pack("I", socket.htonl(len(plaintext))) + plaintext
|
||
if receiveid is None:
|
||
raise AttributeError("'NoneType' object has no attribute 'encode'")
|
||
plaintext += receiveid.encode()
|
||
|
||
# 使用自定义的填充方式对明文进行补位填充
|
||
pkcs7 = PKCS7Encoder()
|
||
plaintext = pkcs7.encode(plaintext)
|
||
# 加密
|
||
cryptor = AES.new(self.key, self.mode, self.key[:16])
|
||
try:
|
||
ciphertext = cryptor.encrypt(plaintext)
|
||
# 使用BASE64对加密后的字符串进行编码
|
||
return WXBizMsgCrypt_OK, base64.b64encode(ciphertext)
|
||
except Exception as e:
|
||
logger = logging.getLogger()
|
||
logger.error(e)
|
||
return WXBizMsgCrypt_EncryptAES_Error, None
|
||
|
||
def decrypt(self, text: str | bytes, receiveid: Optional[str]) -> tuple[int, Optional[bytes]]:
|
||
"""
|
||
解密企业微信密文，提取正文并核对接收方。
|
||
|
||
:param text: Base64 编码的密文
|
||
:param receiveid: 预期的企业微信接收方标识
|
||
:return: 错误码与正文字节；解密、内容拆分或接收方校验失败时正文为 None
|
||
"""
|
||
try:
|
||
cryptor = AES.new(self.key, self.mode, self.key[:16])
|
||
# 使用BASE64对密文进行解码，然后AES-CBC解密
|
||
plain_text: bytes = cryptor.decrypt(base64.b64decode(text))
|
||
except Exception as e:
|
||
logger = logging.getLogger()
|
||
logger.error(e)
|
||
return WXBizMsgCrypt_DecryptAES_Error, None
|
||
try:
|
||
pad = plain_text[-1]
|
||
# 去掉补位字符串
|
||
# 去除16位随机字符串
|
||
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:
|
||
logger = logging.getLogger()
|
||
logger.error(e)
|
||
return WXBizMsgCrypt_IllegalBuffer, None
|
||
|
||
if from_receiveid.decode('utf8') != receiveid:
|
||
return WXBizMsgCrypt_ValidateCorpid_Error, None
|
||
return 0, xml_content
|
||
|
||
@staticmethod
|
||
def get_random_str() -> bytes:
|
||
"""
|
||
生成加密明文前缀使用的 16 位十进制随机数字。
|
||
|
||
:return: 16 个数字字符组成的字节串
|
||
"""
|
||
return str(random.randint(1000000000000000, 9999999999999999)).encode()
|
||
|
||
|
||
class WXBizMsgCrypt(object):
|
||
"""
|
||
验证企业微信回调并封装加解密错误码。
|
||
"""
|
||
def __init__(self, sToken: Optional[str], sEncodingAESKey: Optional[str], sReceiveId: Optional[str]) -> None:
|
||
"""
|
||
解码并验证企业微信配置的 AES 密钥。
|
||
|
||
:param sToken: 回调签名使用的令牌
|
||
:param sEncodingAESKey: 去掉末尾填充符的 Base64 密钥文本
|
||
:param sReceiveId: 企业微信接收方标识
|
||
:raises FormatException: 密钥缺失、无法解码或解码结果不是 32 字节
|
||
"""
|
||
try:
|
||
if sEncodingAESKey is None:
|
||
raise TypeError("unsupported operand type(s) for +: 'NoneType' and 'str'")
|
||
self.key = base64.b64decode(sEncodingAESKey + "=")
|
||
assert len(self.key) == 32
|
||
except Exception as err:
|
||
print(str(err))
|
||
throw_exception("[error]: EncodingAESKey unvalid !", FormatException)
|
||
self.m_sToken = sToken
|
||
self.m_sReceiveId = sReceiveId
|
||
|
||
|
||
def VerifyURL(self, sMsgSignature: str, sTimeStamp: str | int, sNonce: str, sEchoStr: str) -> tuple[int, Optional[bytes]]:
|
||
"""
|
||
核对 URL 验证请求的签名，再解密返回验证内容。
|
||
|
||
:param sMsgSignature: URL 查询参数 msg_signature
|
||
:param sTimeStamp: URL 查询参数 timestamp，应传入文本以便参与签名排序
|
||
:param sNonce: URL 查询参数 nonce
|
||
:param sEchoStr: URL 查询参数 echostr 的密文
|
||
:return: 错误码与解密后的验证字节；校验失败时内容为 None
|
||
"""
|
||
sha1 = SHA1()
|
||
ret, signature = sha1.getSHA1(self.m_sToken, sTimeStamp, sNonce, sEchoStr)
|
||
if ret != 0:
|
||
return ret, None
|
||
if not signature == sMsgSignature:
|
||
return WXBizMsgCrypt_ValidateSignature_Error, None
|
||
pc = Prpcrypt(self.key)
|
||
ret, sReplyEchoStr = pc.decrypt(sEchoStr, self.m_sReceiveId)
|
||
return ret, sReplyEchoStr
|
||
|
||
def EncryptMsg(self, sReplyMsg: str, sNonce: str, timestamp: Optional[str] = None) -> tuple[int, Optional[str]]:
|
||
"""
|
||
加密回复正文并生成带签名的 XML 数据包。
|
||
|
||
:param sReplyMsg: 待回复的 XML 消息文本
|
||
:param sNonce: 回复随机串，可沿用请求的 nonce
|
||
:param timestamp: 秒级时间戳文本；None 使用当前时间
|
||
:return: 错误码与完整加密回复 XML；加密或签名失败时 XML 为 None
|
||
"""
|
||
pc = Prpcrypt(self.key)
|
||
ret, encrypted = pc.encrypt(sReplyMsg, self.m_sReceiveId)
|
||
if ret != 0:
|
||
return ret, None
|
||
# encrypt 的成功分支只返回 base64 bytes，失败时不可对 None 解码。
|
||
encrypt = cast(bytes, encrypted).decode('utf8')
|
||
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)
|
||
if ret != 0:
|
||
return ret, None
|
||
xmlParse = XMLParse()
|
||
return ret, xmlParse.generate(encrypt, signature, timestamp, sNonce)
|
||
|
||
def DecryptMsg(self, sPostData: str | bytes, sMsgSignature: str, sTimeStamp: str, sNonce: str) -> tuple[int, Optional[bytes]]:
|
||
"""
|
||
验证 XML 与消息签名，再解密正文并检查接收方。
|
||
|
||
:param sPostData: POST 请求携带的加密 XML 数据
|
||
:param sMsgSignature: URL 查询参数 msg_signature
|
||
:param sTimeStamp: URL 查询参数 timestamp 文本
|
||
:param sNonce: URL 查询参数 nonce
|
||
:return: 错误码与原始正文字节；解析、签名或解密失败时正文为 None
|
||
"""
|
||
# 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 WXBizMsgCrypt_ValidateSignature_Error, None
|
||
pc = Prpcrypt(self.key)
|
||
# SHA1 成功已证明密文为字符串；空字段会在签名计算阶段返回错误。
|
||
ret, xml_content = pc.decrypt(cast(str, encrypt), self.m_sReceiveId)
|
||
return ret, xml_content
|