maimaiDX-Api/API_TitleServer.py

# 舞萌DX 2024
# 标题服务器通讯实现

import zlib
import hashlib
import requests
from loguru import logger
import random
import time

from ctypes import c_int32

from Crypto.Cipher import AES
from Crypto.Util.Padding import unpad

from Config import *

# 舞萌DX 2024
AesKey = "n7bx6:@Fg_:2;5E89Phy7AyIcpxEQ:R@"
AesIV = ";;KjR1C3hgB1ovXa"
ObfuscateParam = "BEs2D5vW"

class WahlapServerBoomedError(Exception):
    pass
    
class Request500Error(Exception):
    pass

class AES_PKCS7(object):
    def __init__(self, key: str, iv: str):
        self.key = key.encode('utf-8')
        self.iv = iv.encode('utf-8')
        self.mode = AES.MODE_CBC

    def encrypt(self, content):
        cipher = AES.new(self.key, AES.MODE_CBC, self.iv)
        content_padding = self.pkcs7padding(content)
        encrypt_bytes = cipher.encrypt(content_padding.encode('utf-8'))
        return encrypt_bytes

    def decrypt(self, content):
        cipher = AES.new(self.key, AES.MODE_CBC, self.iv)
        return cipher.decrypt(content)
    
    def pkcs7unpadding(self, text):
        length = len(text)
        unpadding = ord(text[length - 1])
        return text[0:length - unpadding]

    def pkcs7padding(self, text):
        bs = 16
        length = len(text)
        bytes_length = len(text.encode('utf-8'))
        padding_size = length if (bytes_length == length) else bytes_length
        padding = bs - padding_size % bs
        padding_text = chr(padding) * padding
        return text + padding_text

def SDGBApiHash(api):
    return hashlib.md5((api+"MaimaiChn"+ObfuscateParam).encode()).hexdigest()

def apiSDGB(data:str, useApi, agentExtraData, noLog=False):
    """
    舞萌DX 2024 API 通讯用函数
    :param data: 请求数据
    :param useApi: 使用的 API
    :param agentExtraData: UA 附加信息，机台相关则为狗号（如A63E01E9564），用户相关则为 UID
    :param noLog: 是否不记录日志
    """
    maxRetries = 3

    # 历史遗留代码有时候会传入 int，故先全部转 str
    agentExtra = str(agentExtraData)

    # 编码好请求，准备发送
    aes = AES_PKCS7(AesKey, AesIV)
    data = data
    data_enc = aes.encrypt(data)
    data_def = zlib.compress(data_enc)
    requests.packages.urllib3.disable_warnings()
    endpoint = "https://maimai-gm.wahlap.com:42081/Maimai2Servlet/"

    if not noLog:
        logger.debug("TitleServer Request Start: "+ str(useApi)+" , Data: "+str(data))

    retries = 0
    while retries < maxRetries:
        try:
            # 发送请求
            responseRaw = requests.post(endpoint + SDGBApiHash(useApi), headers={
                "User-Agent": f"{SDGBApiHash(useApi)}#{agentExtra}", 
                "Content-Type": "application/json",
                "Mai-Encoding": "1.40",
                "Accept-Encoding": "",
                "Charset": "UTF-8", 
                "Content-Encoding": "deflate", 
                "Expect": "100-continue"
            }, data=data_def, verify=False)
            logger.debug("TitleServer Request Sent.")
            
            logger.debug("TitleServer Response Code: " + str(responseRaw.status_code))
            # 如果是 404 或 500，直接抛出异常，不再继续重试
            match responseRaw.status_code:
                case 200:
                    logger.debug("Request 200 OK!")
                case 404:
                    logger.error(f"Request 404! ")
                    raise NotImplementedError
                case 500:
                    logger.error(f"Request Failed! 500!!!! ")
                    raise Request500Error
                case _:
                    logger.error(f"Request Failed! {responseRaw.status_code}")
                    raise NotImplementedError
            responseContent = responseRaw.content
            # 尝试解压请求
            try:
                responseDecompressed = zlib.decompress(responseContent)
                logger.debug("Successfully decompressed response.")
            except zlib.error as e:
                logger.warning(f"RAW Response: {responseContent}")
                logger.warning(f"Wahlap Server Boomed! Will now retry.{e}")
                retries += 1
                time.sleep(4) # 休眠4秒后重试
                continue
            # 解压成功，解密请求并返回
            resultResponse = unpad(aes.decrypt(responseDecompressed), 16).decode()
            logger.info("TitleServer:" + useApi + " Response: " + str(responseRaw.status_code))
            if not noLog:
                logger.debug("TitleServer Response: " + str(resultResponse))
            return resultResponse
        
        # 除了 404 和 500 之外的错误重试
        except Request500Error:
            raise Request500Error("500，请求格式错误")
        except NotImplementedError:
            raise NotImplementedError("请求未知错误")
        except Exception as e:
            logger.warning(f"Request Failed! Will now retry.. {e}")
            retries += 1
            time.sleep(3)
    else:
        # 重试次数用尽，WahlapServerBoomedError
        raise WahlapServerBoomedError("重试多次仍然不能成功请求")
    

def calcSpecialNumber():
    """使用 c_int32 实现的 SpecialNumber 算法"""
    rng = random.SystemRandom()
    num2 = rng.randint(1, 1037933) * 2069
    num2 += 0x400
    num2 = c_int32(num2).value
    result = c_int32(0)
    for _ in range(32):
        result.value <<= 1
        result.value += num2 & 1
        num2 >>= 1
    return c_int32(result.value).value


def calcSpecialNumber2():
    """实验性替代 SpecialNumber 算法"""
    max = 1037933
    num2 = random.randint(1, max) * 2069

    num2 += 1024  # specialnum
    num3 = 0
    for i in range(0, 32):
        num3 <<= 1
        num3 += num2 % 2
        num2 >>= 1

    return num3