maimaiDX-Api/API_TitleServer.py

# 舞萌DX
# 标题服务器通讯实现

import zlib
import hashlib
import httpx
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 *
import certifi

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

class SDGBApiError(Exception):
    pass
    
class SDGBRequestError(SDGBApiError):
    pass

class SDGBResponseError(SDGBApiError):
    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 getSDGBApiHash(api):
    # API 的 Hash 的生成
    # 有空做一下 Hash 的彩虹表？
    return hashlib.md5((api+"MaimaiChn"+ObfuscateParam).encode()).hexdigest()

def apiSDGB(data:str, targetApi:str, userAgentExtraData:str, noLog:bool=False, timeout:int=5):
    """
    舞萌DX 2024 API 通讯用函数
    :param data: 请求数据
    :param targetApi: 使用的 API
    :param userAgentExtraData: 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
    agentExtra = str(userAgentExtraData)
    aes = AES_PKCS7(AesKey, AesIV)
    reqData_encrypted = aes.encrypt(data)
    reqData_deflated = zlib.compress(reqData_encrypted)
    endpoint = "https://maimai-gm.wahlap.com:42081/Maimai2Servlet/"
    if not noLog:
        logger.debug(f"开始请求 {targetApi}，以 {data}")

    retries = 0
    while retries < maxRetries:
        try:
            response = httpx.post(
                url=endpoint + getSDGBApiHash(targetApi),
                headers={
                    "User-Agent": f"{getSDGBApiHash(targetApi)}#{agentExtra}",
                    "Content-Type": "application/json",
                    "Mai-Encoding": "1.40",
                    "Accept-Encoding": "",
                    "Charset": "UTF-8",
                    "Content-Encoding": "deflate",
                    "Expect": "100-continue"
                },
                content=reqData_deflated,
                verify=certifi.where(),
                timeout=timeout
            )
            if not noLog:
                logger.info(f"{targetApi} 请求结果: {response.status_code}")

            if response.status_code == 200:
                logger.debug("200 OK!")
            else:
                errorMessage = f"请求失败: {response.status_code}"
                logger.error(errorMessage)
                raise SDGBRequestError(errorMessage)

            responseRAWContent = response.content

            try:
                responseDecompressed = zlib.decompress(responseRAWContent)
                logger.debug("成功解压响应！")
            except:
                logger.warning(f"无法解压，得到的原始响应: {responseRAWContent}")
                raise SDGBResponseError("解压失败")
            try:
                resultResponse = unpad(aes.decrypt(responseDecompressed), 16).decode()
                logger.debug(f"成功解密响应！")
            except:
                logger.warning(f"解密失败，得到的原始响应: {responseDecompressed}")
                raise SDGBResponseError("解密失败")
            
            if not noLog:
                logger.debug(f"响应: {resultResponse}")
            return resultResponse
        
        # 异常处理
        except SDGBRequestError as e:
            # 请求格式错误，不需要重试
            raise SDGBRequestError("请求格式错误")
        except SDGBResponseError as e:
            # 响应解析错误，重试但是只一次
            logger.warning(f"将重试一次 Resp Err: {e}")
            retries += 2
            time.sleep(2)
        except Exception as e:
            # 其他错误，重试
            logger.warning(f"将开始重试请求. {e}")
            retries += 1
            time.sleep(2)

    raise SDGBApiError("重试多次仍然无法成功请求服务器")

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