artemis/titles/chuni/index.py

from starlette.requests import Request
from starlette.routing import Route
from starlette.responses import Response
import logging
import coloredlogs
from logging.handlers import TimedRotatingFileHandler
import zlib
import yaml
import json
import inflection
import string
from Crypto.Cipher import AES
from Crypto.Util.Padding import pad
from Crypto.Protocol.KDF import PBKDF2
from Crypto.Hash import SHA1
from os import path
from typing import Tuple, Dict, List

from core import CoreConfig, Utils
from core.title import BaseServlet
from .config import ChuniConfig
from .const import ChuniConstants
from .base import ChuniBase
from .plus import ChuniPlus
from .air import ChuniAir
from .airplus import ChuniAirPlus
from .star import ChuniStar
from .starplus import ChuniStarPlus
from .amazon import ChuniAmazon
from .amazonplus import ChuniAmazonPlus
from .crystal import ChuniCrystal
from .crystalplus import ChuniCrystalPlus
from .paradise import ChuniParadise
from .new import ChuniNew
from .newplus import ChuniNewPlus
from .sun import ChuniSun
from .sunplus import ChuniSunPlus
from .luminous import ChuniLuminous

class ChuniServlet(BaseServlet):
    def __init__(self, core_cfg: CoreConfig, cfg_dir: str) -> None:
        super().__init__(core_cfg, cfg_dir)
        self.game_cfg = ChuniConfig()
        self.hash_table: Dict[str, Dict[str, str]] = {}
        if path.exists(f"{cfg_dir}/{ChuniConstants.CONFIG_NAME}"):
            self.game_cfg.update(
                yaml.safe_load(open(f"{cfg_dir}/{ChuniConstants.CONFIG_NAME}"))
            )

        self.versions = [
            ChuniBase,
            ChuniPlus,
            ChuniAir,
            ChuniAirPlus,
            ChuniStar,
            ChuniStarPlus,
            ChuniAmazon,
            ChuniAmazonPlus,
            ChuniCrystal,
            ChuniCrystalPlus,
            ChuniParadise,
            ChuniNew,
            ChuniNewPlus,
            ChuniSun,
            ChuniSunPlus,
            ChuniLuminous,
        ]

        self.logger = logging.getLogger("chuni")

        if not hasattr(self.logger, "inited"):
            log_fmt_str = "[%(asctime)s] Chunithm | %(levelname)s | %(message)s"
            log_fmt = logging.Formatter(log_fmt_str)
            fileHandler = TimedRotatingFileHandler(
                "{0}/{1}.log".format(self.core_cfg.server.log_dir, "chuni"),
                encoding="utf8",
                when="d",
                backupCount=10,
            )

            fileHandler.setFormatter(log_fmt)

            consoleHandler = logging.StreamHandler()
            consoleHandler.setFormatter(log_fmt)

            self.logger.addHandler(fileHandler)
            self.logger.addHandler(consoleHandler)

            self.logger.setLevel(self.game_cfg.server.loglevel)
            coloredlogs.install(
                level=self.game_cfg.server.loglevel, logger=self.logger, fmt=log_fmt_str
            )
            self.logger.inited = True

        known_iter_counts = {
            ChuniConstants.VER_CHUNITHM_CRYSTAL_PLUS: 67,
            f"{ChuniConstants.VER_CHUNITHM_CRYSTAL_PLUS}_int": 25, # SUPERSTAR
            ChuniConstants.VER_CHUNITHM_PARADISE: 44,
            f"{ChuniConstants.VER_CHUNITHM_PARADISE}_int": 51, # SUPERSTAR PLUS
            ChuniConstants.VER_CHUNITHM_NEW: 54,
            f"{ChuniConstants.VER_CHUNITHM_NEW}_int": 49,
            ChuniConstants.VER_CHUNITHM_NEW_PLUS: 25,
            f"{ChuniConstants.VER_CHUNITHM_NEW_PLUS}_int": 31,
            ChuniConstants.VER_CHUNITHM_SUN: 70,
            f"{ChuniConstants.VER_CHUNITHM_SUN}_int": 35,
            ChuniConstants.VER_CHUNITHM_SUN_PLUS: 36,
            f"{ChuniConstants.VER_CHUNITHM_SUN_PLUS}_int": 36,
            ChuniConstants.VER_CHUNITHM_LUMINOUS: 8,
            f"{ChuniConstants.VER_CHUNITHM_LUMINOUS}_int": 8,
        }

        for version, keys in self.game_cfg.crypto.keys.items():
            if len(keys) < 3:
                continue

            if isinstance(version, int):
                version_idx = version
            else:
                version_idx = int(version.split("_")[0])
            
            salt = bytes.fromhex(keys[2])

            if len(keys) >= 4:
                iter_count = keys[3]
            elif (iter_count := known_iter_counts.get(version)) is None:
                self.logger.error(
                    "Number of iteration rounds for version %s is not known, but it is not specified in the config",
                    version,
                )
                continue

            self.hash_table[version] = {}
            method_list = [
                method
                for method in dir(self.versions[version_idx])
                if not method.startswith("__")
            ]

            for method in method_list:
                method_fixed = inflection.camelize(method)[6:-7]

                # This only applies for CHUNITHM NEW International and later for some reason.
                # CHUNITHM SUPERSTAR (PLUS) did not add "Exp" to the endpoint when hashing.
                if (
                    isinstance(version, str)
                    and version.endswith("_int")
                    and version_idx >= ChuniConstants.VER_CHUNITHM_NEW
                ):
                    method_fixed += "C3Exp"
                    
                hash = PBKDF2(
                    method_fixed,
                    salt,
                    128,
                    count=iter_count,
                    hmac_hash_module=SHA1,
                )

                hashed_name = hash.hex()[:32] # truncate unused bytes like the game does
                self.hash_table[version][hashed_name] = method_fixed

                self.logger.debug(
                    f"Hashed v{version} method {method_fixed} with {salt} to get {hashed_name}"
                )

    @classmethod
    def is_game_enabled(
        cls, game_code: str, core_cfg: CoreConfig, cfg_dir: str
    ) -> bool:
        game_cfg = ChuniConfig()
        if path.exists(f"{cfg_dir}/{ChuniConstants.CONFIG_NAME}"):
            game_cfg.update(
                yaml.safe_load(open(f"{cfg_dir}/{ChuniConstants.CONFIG_NAME}"))
            )

        if not game_cfg.server.enable:
            return False

        return True

    def get_allnet_info(self, game_code: str, game_ver: int, keychip: str) -> Tuple[str, str]:
        if not self.core_cfg.server.is_using_proxy and Utils.get_title_port(self.core_cfg) != 80:
            return (f"http://{self.core_cfg.server.hostname}:{Utils.get_title_port(self.core_cfg)}/{game_code}/{game_ver}/", self.core_cfg.server.hostname)

        return (f"http://{self.core_cfg.server.hostname}/{game_code}/{game_ver}/", self.core_cfg.server.hostname)

    def get_routes(self) -> List[Route]:
        return [
            Route("/{game:str}/{version:int}/ChuniServlet/{endpoint:str}", self.render_POST, methods=['POST']),
            Route("/{game:str}/{version:int}/ChuniServlet/MatchingServer/{endpoint:str}", self.render_POST, methods=['POST']),
        ]

    async def render_POST(self, request: Request) -> bytes:
        endpoint: str = request.path_params.get('endpoint')
        version: int = request.path_params.get('version')
        game_code: str = request.path_params.get('game')

        if endpoint.lower() == "ping":
            return Response(zlib.compress(b'{"returnCode": "1"}'))

        req_raw = await request.body()

        encrtped = False
        internal_ver = 0
        client_ip = Utils.get_ip_addr(request)

        if game_code == "SDHD" or game_code == "SDBT": # JP
          if version < 105:  # 1.0
              internal_ver = ChuniConstants.VER_CHUNITHM
          elif version >= 105 and version < 110:  # PLUS
              internal_ver = ChuniConstants.VER_CHUNITHM_PLUS
          elif version >= 110 and version < 115:  # AIR
              internal_ver = ChuniConstants.VER_CHUNITHM_AIR
          elif version >= 115 and version < 120:  # AIR PLUS
              internal_ver = ChuniConstants.VER_CHUNITHM_AIR_PLUS
          elif version >= 120 and version < 125:  # STAR
              internal_ver = ChuniConstants.VER_CHUNITHM_STAR
          elif version >= 125 and version < 130:  # STAR PLUS
              internal_ver = ChuniConstants.VER_CHUNITHM_STAR_PLUS
          elif version >= 130 and version < 135:  # AMAZON
              internal_ver = ChuniConstants.VER_CHUNITHM_AMAZON
          elif version >= 135 and version < 140:  # AMAZON PLUS
              internal_ver = ChuniConstants.VER_CHUNITHM_AMAZON_PLUS
          elif version >= 140 and version < 145:  # CRYSTAL
              internal_ver = ChuniConstants.VER_CHUNITHM_CRYSTAL
          elif version >= 145 and version < 150:  # CRYSTAL PLUS
              internal_ver = ChuniConstants.VER_CHUNITHM_CRYSTAL_PLUS
          elif version >= 150 and version < 200:  # PARADISE
              internal_ver = ChuniConstants.VER_CHUNITHM_PARADISE
          elif version >= 200 and version < 205:  # NEW!!
              internal_ver = ChuniConstants.VER_CHUNITHM_NEW
          elif version >= 205 and version < 210:  # NEW PLUS!!
              internal_ver = ChuniConstants.VER_CHUNITHM_NEW_PLUS
          elif version >= 210 and version < 215:  # SUN
              internal_ver = ChuniConstants.VER_CHUNITHM_SUN
          elif version >= 215 and version < 220:  # SUN PLUS
              internal_ver = ChuniConstants.VER_CHUNITHM_SUN_PLUS
          elif version >= 220:  # LUMINOUS
              internal_ver = ChuniConstants.VER_CHUNITHM_LUMINOUS
        elif game_code == "SDGS": # Int
          if version < 105: # SUPERSTAR
              internal_ver = ChuniConstants.VER_CHUNITHM_CRYSTAL_PLUS
          elif version >= 105 and version < 110: # SUPERSTAR PLUS *Cursed but needed due to different encryption key
              internal_ver = ChuniConstants.VER_CHUNITHM_PARADISE
          elif version >= 110 and version < 115: # NEW
              internal_ver = ChuniConstants.VER_CHUNITHM_NEW
          elif version >= 115 and version < 120: # NEW PLUS!!
              internal_ver = ChuniConstants.VER_CHUNITHM_NEW_PLUS
          elif version >= 120 and version < 125: # SUN
              internal_ver = ChuniConstants.VER_CHUNITHM_SUN
          elif version >= 125 and version < 130: # SUN PLUS
              internal_ver = ChuniConstants.VER_CHUNITHM_SUN_PLUS
          elif version >= 130: # LUMINOUS
              internal_ver = ChuniConstants.VER_CHUNITHM_LUMINOUS

        if all(c in string.hexdigits for c in endpoint) and len(endpoint) == 32:
            # If we get a 32 character long hex string, it's a hash and we're
            # doing encrypted. The likelihood of false positives is low but
            # technically not 0

            if game_code == "SDGS":
                crypto_cfg_key = f"{internal_ver}_int"
                hash_table_key = f"{internal_ver}_int"
            else:
                crypto_cfg_key = internal_ver
                hash_table_key = internal_ver

            if internal_ver < ChuniConstants.VER_CHUNITHM_NEW:
                endpoint = request.headers.get("User-Agent").split("#")[0]

            else:
                if hash_table_key not in self.hash_table:
                    self.logger.error(
                        f"v{version} does not support encryption or no keys entered"
                    )
                    return Response(zlib.compress(b'{"stat": "0"}'))

                elif endpoint.lower() not in self.hash_table[hash_table_key]:
                    self.logger.error(
                        f"No hash found for v{version} endpoint {endpoint}"
                    )
                    return Response(zlib.compress(b'{"stat": "0"}'))

                endpoint = self.hash_table[hash_table_key][endpoint.lower()]

            try:
                crypt = AES.new(
                    bytes.fromhex(self.game_cfg.crypto.keys[crypto_cfg_key][0]),
                    AES.MODE_CBC,
                    bytes.fromhex(self.game_cfg.crypto.keys[crypto_cfg_key][1]),
                )

                req_raw = crypt.decrypt(req_raw)

            except Exception as e:
                self.logger.error(
                    f"Failed to decrypt v{version} request to {endpoint} -> {e}"
                )
                return Response(zlib.compress(b'{"stat": "0"}'))

            encrtped = True

        if (
            not encrtped
            and self.game_cfg.crypto.encrypted_only
            and internal_ver >= ChuniConstants.VER_CHUNITHM_CRYSTAL_PLUS
        ):
            self.logger.error(
                f"Unencrypted v{version} {endpoint} request, but config is set to encrypted only: {req_raw}"
            )
            return Response(zlib.compress(b'{"stat": "0"}'))

        try:
            unzip = zlib.decompress(req_raw)

        except zlib.error as e:
            self.logger.error(
                f"Failed to decompress v{version} {endpoint} request -> {e}"
            )
            return Response(zlib.compress(b'{"stat": "0"}'))

        req_data = json.loads(unzip)

        self.logger.info(f"v{version} {endpoint} request from {client_ip}")
        self.logger.debug(req_data)

        if game_code == "SDGS" and version >= 110:
            endpoint = endpoint.replace("C3Exp", "")
        elif game_code == "SDGS" and version < 110:
            endpoint = endpoint.replace("Exp", "")
        else:
            endpoint = endpoint

        func_to_find = "handle_" + inflection.underscore(endpoint) + "_request"
        handler_cls = self.versions[internal_ver](self.core_cfg, self.game_cfg)

        if not hasattr(handler_cls, func_to_find):
            self.logger.warning(f"Unhandled v{version} request {endpoint}")
            resp = {"returnCode": 1}

        else:
            try:
                handler = getattr(handler_cls, func_to_find)
                resp = await handler(req_data)

            except Exception as e:
                self.logger.error(f"Error handling v{version} method {endpoint} - {e}")
                return Response(zlib.compress(b'{"stat": "0"}'))

        if resp is None:
            resp = {"returnCode": 1}

        self.logger.debug(f"Response {resp}")

        zipped = zlib.compress(json.dumps(resp, ensure_ascii=False).encode("utf-8"))

        if not encrtped:
            return Response(zipped)

        padded = pad(zipped, 16)

        crypt = AES.new(
            bytes.fromhex(self.game_cfg.crypto.keys[crypto_cfg_key][0]),
            AES.MODE_CBC,
            bytes.fromhex(self.game_cfg.crypto.keys[crypto_cfg_key][1]),
        )

        return Response(crypt.encrypt(padded))