+# encoding: utf8
+from __future__ import absolute_import, division
+
+from base64 import urlsafe_b64decode
+from collections import namedtuple
+from itertools import izip
+import logging
+from random import sample
+from string import uppercase, lowercase, digits
+import struct
+
+import pokedex.db
+import pokedex.db.tables as tables
+import pokedex.formulae
+from pokedex.savefile import PokemonSave
+from pylons import config, request, response, session, tmpl_context as c, url
+from pylons.controllers.util import abort, redirect_to
+from sqlalchemy import and_, or_, not_
+from sqlalchemy.orm import aliased, contains_eager, eagerload, eagerload_all, join
+from sqlalchemy.orm.exc import NoResultFound
+from sqlalchemy.sql import func
+
+from spline import model
+from spline.model import meta
+from spline.lib.base import BaseController, render
+from spline.lib import helpers as h
+
+from spline.plugins.gts.model import GTSPokemon
+
+log = logging.getLogger(__name__)
+
+
+### Utility functions
+
+def gts_prng(seed):
+ """Implements the GTS's linear congruential generator.
+
+ I love typing that out. It makes me sounds so smart.
+
+ Yields magical numbers."""
+ # 0xabcd => 0xabcdabcd
+ seed = seed | (seed << 16)
+ while True:
+ seed = (seed * 0x45 + 0x1111) & 0x7fffffff # signed dword!
+ yield (seed >> 16) & 0xff
+
+def stream_decipher(data, keystream):
+ """Reverses a stream cipher, given iterable data and keystream.
+
+ Yields decrypted bytes.
+ """
+ for c, key in izip(data, keystream):
+ new_c = (ord(c) ^ key) & 0xff
+ yield chr(new_c)
+
+
+def decrypt_data(data):
+ """Takes a binary blob uploaded from a game and returns the original binary
+ blob. Depending on your perspective, the returned value may be more
+ intelligible.
+ """
+ # GTS encryption is a simple stream cipher.
+ # The first four bytes of the data are a header containing an obfuscated
+ # key; the rest is the message
+ obf_key_blob, message = data[0:4], data[4:]
+ obf_key, = struct.unpack('>I', obf_key_blob)
+ key = obf_key ^ 0x4a3b2c1d
+
+ # Data is XORed with the output of an LCG, like everything else in Pokémon
+ return ''.join( stream_decipher(message, gts_prng(key)) )
+
+
+### Controller!
+
+def dbg(*args):
+ #print ' '.join(args)
+ pass
+
+class GTSController(BaseController):
+
+ def dispatch(self, page):
+ """We do our own dispatching for two reasons:
+
+ 1. All requests do challenge/response before anything, and it's easier
+ to do that and then dispatch than copy/paste some block of code to
+ every action.
+
+ 2. Easier to dump stuff if desired.
+ """
+
+ dbg(request)
+
+ # Always return binary!
+ response.headers['Content-type'] = 'application/octet-stream'
+
+ if 'hash' in request.params:
+ # Okay, already done the response. Decrypt, then dispatch!
+ if request.params['data']:
+ # Note: base64 doesn't like unicode. Go figure. It's binary
+ # junk, anyway.
+ encrypted_data = urlsafe_b64decode(str(request.params['data']))
+ data = decrypt_data(encrypted_data)
+ data = data[4:] # data always starts with pid; we don't care
+ else:
+ data = ''
+
+ method = 'page_' + page
+ if not hasattr(self, method):
+ dbg("NOT YET IMPLEMENTED?")
+ abort(404)
+
+ res = getattr(self, method)(request.params['pid'], data)
+ dbg("RESPONDING WITH ", type(res), len(res), repr(res))
+ return res
+
+ # No hash. Need to issue a challenge. It's random, so whatever
+ return ''.join(sample( uppercase + lowercase + digits, 32 ))
+
+ ### Actual pages
+
+ def page_info(self, pid, data):
+ """info.asp
+
+ Apparently always returns 0x0001. Probably just a ping to see if the
+ server is up.
+ """
+
+ return '\x01\x00'
+
+ def page_setProfile(self, pid, data):
+ """setProfile.asp
+
+ Only Pt and later check this page. Don't know why. It returns eight
+ NULs, every time.
+ """
+
+ return '\x00' * 8
+
+ def page_result(self, pid, data):
+ u"""result.asp
+
+ The good part!
+
+ This checks the game's status on the GTS. If there's nothing
+ interesting to report, it returns 0x0005. If the game has a Pokémon up
+ on the GTS, it returns 0x0004.
+
+ However... if the game has a Pokémon waiting to come to it, it returns
+ that entire Pokémon struct! No header, no encryption. Just a regular
+ ol' Pokémon blob.
+ """
+
+ # Check for an existing Pokémon
+ # TODO support multiple!
+ try:
+ stored_pokemon = meta.Session.query(model.GTSPokemon) \
+ .filter_by(pid=pid) \
+ .one()
+ # We've got one! Cool, send it back. The game will ask us to
+ # delete it after receiving successfully
+ pokemon_save = PokemonSave(stored_pokemon.pokemon_blob)
+ return pokemon_save.as_encrypted
+
+ except:
+ # Nothing
+ return '\x05\x00'
+
+ def page_delete(self, pid, data):
+ u"""delete.asp
+
+ If a Pokémon is received from result.asp, the game requests this page
+ to confirm that the incoming Pokémon may be deleted.
+
+ Returns 0x0001.
+ """
+
+ meta.Session.query(model.GTSPokemon).filter_by(pid=pid).delete()
+ meta.Session.commit()
+
+ return '\x01\x00'
+
+ def page_post(self, pid, data):
+ u"""post.asp
+
+ Deposits a Pokémon in the GTS. Returns 0x0001 on success, or 0x000c if
+ the deposit is rejected.
+ """
+
+ try:
+ # The uploaded Pokémon is encrypted, which is not very useful
+ pokemon_save = PokemonSave(data, encrypted=True)
+
+ # Create a record...
+ stored_pokemon = model.GTSPokemon(
+ pid=pid,
+ pokemon_blob=pokemon_save.as_struct,
+ )
+ meta.Session.add(stored_pokemon)
+ meta.Session.commit()
+ return '\x01\x00'
+ except:
+ # If that failed (presumably due to unique key collision), we're
+ # already storing something. Reject!
+ return '\x0c\x00'
+
+ def page_post_finish(self, pid, data):
+ u"""post_finish.asp
+
+ Surely this does something, but for the life of me I can't figure out
+ what.
+
+ Returns 0x0001.
+ """
+ return '\x01\x00'
projects / zzz-spline-gts.git / commitdiff
