Ejemplo n.º 1
0
        public override void ProcessGamestatsRequest(byte[] data, MemoryStream response, string url, int pid, HttpContext context, GamestatsSession session)
        {
            switch (url)
            {
            default:
                SessionManager.Remove(session);

                // unrecognized page url
                ShowError(context, 404);
                return;

                #region Common
            // Called during startup. Seems to contain trainer profile stats.
            case "/pokemondpds/common/setProfile.asp":
            {
                SessionManager.Remove(session);

                if (data.Length != 100)
                {
                    ShowError(context, 400);
                    return;
                }

#if !DEBUG
                try
                {
#endif
                // todo: Figure out what fun stuff is contained in this blob!
                byte[] profileBinary = new byte[100];
                Array.Copy(data, 0, profileBinary, 0, 100);
                TrainerProfile4 profile = new TrainerProfile4(pid, profileBinary);
                Database.Instance.GamestatsSetProfile4(profile);
#if !DEBUG
            }
                catch { }
#endif

                response.Write(new byte[] { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
                               0, 8);
            } break;
                #endregion

                #region GTS
            // Called during startup. Unknown purpose.
            case "/pokemondpds/worldexchange/info.asp":
                SessionManager.Remove(session);

                // todo: find out the meaning of this request.
                // is it simply done to check whether the GTS is online?

                // todo: add a mostly null record to GtsProfiles4 if the
                // player is on D/P. We can still track last visit times
                // and gather trainer profile data from GTS activity.
                response.Write(new byte[] { 0x01, 0x00 }, 0, 2);
                break;

            // Called during startup and when you check your pokemon's status.
            case "/pokemondpds/worldexchange/result.asp":
            {
                SessionManager.Remove(session);

                /* After the above step(s) or performing any of
                 * the tasks below other than searching, the game
                 * makes a request to /pokemondpds/worldexchange/result.asp.
                 * If the game has had a Pokémon sent to it via a trade,
                 * the server responds with the entire encrypted Pokémon
                 * save struct. Otherwise, if there is a Pokémon deposited
                 * in the GTS, it responds with 0x0004; if not, it responds
                 * with 0x0005. */

                GtsRecord4 record = Database.Instance.GtsDataForUser4(pid);

                if (record == null)
                {
                    // No pokemon in the system
                    response.Write(new byte[] { 0x05, 0x00 }, 0, 2);
                }
                else if (record.IsExchanged > 0)
                {
                    // traded pokemon arriving!!!
                    response.Write(record.Save(), 0, 292);
                }
                else
                {
                    // my existing pokemon is in the system, untraded
                    response.Write(new byte[] { 0x04, 0x00 }, 0, 2);
                }

                // other responses:
                // 0-2 causes a BSOD but it flashes siezure. Scary
                // 3 causes it to be "checking GTS's status" forever.
            } break;

            // Called after result.asp returns 4 when you check your pokemon's status
            case "/pokemondpds/worldexchange/get.asp":
            {
                SessionManager.Remove(session);

                // this is only called if result.asp returned 4.
                // todo: what does this do if the contained pokemon is traded??

                GtsRecord4 record = Database.Instance.GtsDataForUser4(pid);

                if (record == null)
                {
                    // No pokemon in the system
                    // what do here?
                    ShowError(context, 400);
                    return;
                }
                else
                {
                    // just write the record whether traded or not...
                    response.Write(record.Save(), 0, 292);
                }
            } break;

            // Called after result.asp returns an inbound pokemon record to delete it
            case "/pokemondpds/worldexchange/delete.asp":
            {
                SessionManager.Remove(session);

                GtsRecord4 record = Database.Instance.GtsDataForUser4(pid);
                if (record == null)
                {
                    response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                }
                else if (record.IsExchanged > 0)
                {
                    // delete the arrived pokemon from the system
                    // todo: add transactions
                    // todo: log the successful trade?
                    // (either here or when the trade is done)
                    bool success = Database.Instance.GtsDeletePokemon4(pid);
                    if (success)
                    {
#if !DEBUG
                        try
                        {
#endif
                        Database.Instance.GtsLogTrade4(record, DateTime.UtcNow);
#if !DEBUG
                    }
                    catch { }
#endif
                        response.Write(new byte[] { 0x01, 0x00 }, 0, 2);
                    }
                    else
                    {
                        response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                    }
                }
                else
                {
                    // own pokemon is there, fail. Use return.asp instead.
                    response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                }
            } break;

            // called to delete your own pokemon after taking it back
            case "/pokemondpds/worldexchange/return.asp":
            {
                SessionManager.Remove(session);

                GtsRecord4 record = Database.Instance.GtsDataForUser4(pid);
                if (record == null)
                {
                    response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                }
                else if (record.IsExchanged > 0)
                {
                    // a traded pokemon is there, fail. Use delete.asp instead.
                    response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                }
                else
                {
                    // delete own pokemon
                    // todo: add transactions
                    bool success = Database.Instance.GtsDeletePokemon4(pid);
                    if (success)
                    {
                        response.Write(new byte[] { 0x01, 0x00 }, 0, 2);
                    }
                    else
                    {
                        response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                    }
                }
            } break;

            // Called when you deposit a pokemon into the system.
            case "/pokemondpds/worldexchange/post.asp":
            {
                if (data.Length != 292)
                {
                    SessionManager.Remove(session);
                    ShowError(context, 400);
                    return;
                }

                // todo: add transaction
                if (Database.Instance.GtsDataForUser4(pid) != null)
                {
                    // there's already a pokemon inside
                    SessionManager.Remove(session);
                    response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                    break;
                }

                // keep the record in memory while we wait for post_finish.asp request
                byte[] recordBinary = new byte[292];
                Array.Copy(data, 0, recordBinary, 0, 292);
                GtsRecord4 record = new GtsRecord4(recordBinary);
                if (!record.Validate())
                {
                    // hack check failed
                    SessionManager.Remove(session);
                    response.Write(new byte[] { 0x0c, 0x00 }, 0, 2);
                    break;
                }

                // the following two fields are blank in the uploaded record.
                // The server must provide them instead.
                record.TimeDeposited = DateTime.UtcNow;
                record.TimeExchanged = null;
                record.IsExchanged   = 0;
                record.PID           = pid;

                session.Tag = record;
                // todo: delete any other post.asp sessions registered under this PID

                response.Write(new byte[] { 0x01, 0x00 }, 0, 2);
            } break;

            case "/pokemondpds/worldexchange/post_finish.asp":
            {
                SessionManager.Remove(session);

                if (data.Length != 8)
                {
                    ShowError(context, 400);
                    return;
                }

                // todo: these _finish requests seem to come with a magic number of 4 bytes
                // at offset 0. Find out what this is supposed to do and how to validate it.

                // find a matching session which contains our record
                GamestatsSession prevSession = SessionManager.FindSession(pid, "/pokemondpds/worldexchange/post.asp");
                if (prevSession == null)
                {
                    response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                    return;
                }

                SessionManager.Remove(prevSession);
                if (prevSession.Tag == null)
                {
                    response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                    return;
                }
                AssertHelper.Assert(prevSession.Tag is GtsRecord4);
                GtsRecord4 record = (GtsRecord4)prevSession.Tag;

                if (Database.Instance.GtsDepositPokemon4(record))
                {
                    response.Write(new byte[] { 0x01, 0x00 }, 0, 2);
                }
                else
                {
                    response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                }
            } break;

            // the search request has a funny bit string request of search terms
            // and just returns a chunk of records end to end.
            case "/pokemondpds/worldexchange/search.asp":
            {
                SessionManager.Remove(session);

                if (data.Length < 7 || data.Length > 8)
                {
                    ShowError(context, 400);
                    return;
                }

                ushort species = BitConverter.ToUInt16(data, 0);
                if (species < 1)
                {
                    ShowError(context, 400);
                    return;
                }

                int resultsCount = (int)data[6];
                if (resultsCount < 1)
                {
                    break;                       // optimize away requests for no rows
                }
                Genders gender   = (Genders)data[2];
                byte    minLevel = data[3];
                byte    maxLevel = data[4];
                // byte 5 unknown
                byte country = 0;
                if (data.Length > 7)
                {
                    country = data[7];
                }

                if (resultsCount > 7)
                {
                    resultsCount = 7;                       // stop DDOS
                }
                GtsRecord4[] records = Database.Instance.GtsSearch4(pid, species, gender, minLevel, maxLevel, country, resultsCount);
                foreach (GtsRecord4 record in records)
                {
                    response.Write(record.Save(), 0, 292);
                }
            } break;

            // the exchange request uploads a record of the exchangee pokemon
            // plus the desired PID to trade for at the very end.
            case "/pokemondpds/worldexchange/exchange.asp":
            {
                if (data.Length != 296)
                {
                    SessionManager.Remove(session);
                    ShowError(context, 400);
                    return;
                }

                byte[] uploadData = new byte[292];
                Array.Copy(data, 0, uploadData, 0, 292);
                GtsRecord4 upload = new GtsRecord4(uploadData);
                upload.IsExchanged = 0;
                int        targetPid = BitConverter.ToInt32(data, 292);
                GtsRecord4 result    = Database.Instance.GtsDataForUser4(targetPid);

                if (result == null || result.IsExchanged != 0)
                {
                    // Pokémon is traded (or was never here to begin with)
                    // todo: I only checked this on GenV. Check that this
                    // is the correct response on GenIV.
                    SessionManager.Remove(session);
                    response.Write(new byte[] { 0x02, 0x00 }, 0, 2);
                    break;
                }

                // enforce request requirements server side
                if (!upload.Validate() || !upload.CanTrade(result))
                {
                    // todo: find the correct codes for these
                    SessionManager.Remove(session);
                    response.Write(new byte[] { 0x0c, 0x00 }, 0, 2);
                    return;
                }

                object[] tag = new GtsRecord4[2];
                tag[0]      = upload;
                tag[1]      = result;
                session.Tag = tag;

                GtsRecord4 tradedResult = result.Clone();
                tradedResult.FlagTraded(upload);     // only real purpose is to generate a proper response

                // todo: we need a mechanism to "reserve" a pokemon being traded at this
                // point in the process, but be able to relinquish it if exchange_finish
                // never happens.
                // Currently, if two people try to take the same pokemon, it will appear
                // to work for both but then fail for the second after they've saved
                // their game. This causes a hard crash and a "save file is corrupt,
                // "previous will be loaded" error when restarting.
                // the reservation can be done in application state and has no reason
                // to touch the database. (exchange_finish won't work anyway if application
                // state is lost.)

                // I also have a hunch that failure to send the exchange_finish request
                // is what causes the notorious GTS glitch where a pokemon is listed
                // under the wrong species and you can't trade it

                response.Write(result.Save(), 0, 292);
            } break;

            case "/pokemondpds/worldexchange/exchange_finish.asp":
            {
                SessionManager.Remove(session);

                if (data.Length != 8)
                {
                    ShowError(context, 400);
                    return;
                }

                // find a matching session which contains our record
                GamestatsSession prevSession = SessionManager.FindSession(pid, "/pokemondpds/worldexchange/exchange.asp");
                if (prevSession == null)
                {
                    response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                    return;
                }

                SessionManager.Remove(prevSession);
                if (prevSession.Tag == null)
                {
                    response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                    return;
                }
                AssertHelper.Assert(prevSession.Tag is GtsRecord4[]);
                GtsRecord4[] tag = (GtsRecord4[])prevSession.Tag;
                AssertHelper.Assert(tag.Length == 2);
                AssertHelper.Assert(tag[0] is GtsRecord4);
                AssertHelper.Assert(tag[0] is GtsRecord4);

                GtsRecord4 upload = (GtsRecord4)tag[0];
                GtsRecord4 result = (GtsRecord4)tag[1];

                if (Database.Instance.GtsTradePokemon4(upload, result))
                {
#if !DEBUG
                    try
                    {
#endif
                    Database.Instance.GtsLogTrade4(result, null);
#if !DEBUG
                }
                catch { }
#endif
                    response.Write(new byte[] { 0x01, 0x00 }, 0, 2);
                }
                else
                {
                    response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                }
            } break;
                #endregion

                #region Battle Tower
            case "/pokemondpds/battletower/info.asp":
                SessionManager.Remove(session);

                // Probably an availability/status code.
                // todo: See how the game reacts to various values.
                response.Write(new byte[] { 0x01, 0x00 }, 0, 2);
                break;

            case "/pokemondpds/battletower/roomnum.asp":
                SessionManager.Remove(session);

                //byte rank = data[0x00];
                response.Write(new byte[] { 0x32, 0x00 }, 0, 2);
                break;

            case "/pokemondpds/battletower/download.asp":
            {
                SessionManager.Remove(session);

                if (data.Length != 2)
                {
                    ShowError(context, 400);
                    return;
                }

                byte rank    = data[0x00];
                byte roomNum = data[0x01];

                if (rank > 9 || roomNum > 49)
                {
                    ShowError(context, 400);
                    return;
                }

                BattleTowerRecord4[]  opponents     = Database.Instance.BattleTowerGetOpponents4(pid, rank, roomNum);
                BattleTowerProfile4[] leaders       = Database.Instance.BattleTowerGetLeaders4(rank, roomNum);
                BattleTowerRecord4[]  fakeOpponents = FakeOpponentGenerator4.GenerateFakeOpponents(7 - opponents.Length);

                foreach (BattleTowerRecord4 record in fakeOpponents)
                {
                    response.Write(record.Save(), 0, 228);
                }

                foreach (BattleTowerRecord4 record in opponents)
                {
                    response.Write(record.Save(), 0, 228);
                }

                foreach (BattleTowerProfile4 leader in leaders)
                {
                    response.Write(leader.Save(), 0, 34);
                }

                // This is completely insane. The game crashes when you
                // use Check Leaders if the response arrives too fast,
                // so we artificially delay it.
                // todo: This is slower than it needs to be if the
                // database is slow to respond. We should sleep for a
                // variable time based on when the request was received.
                Thread.Sleep(500);
            } break;

            case "/pokemondpds/battletower/upload.asp":
            {
                SessionManager.Remove(session);

                if (data.Length != 239)
                {
                    ShowError(context, 400);
                    return;
                }

                BattleTowerRecord4 record = new BattleTowerRecord4(data, 0);

                record.Rank       = data[0xe4];
                record.RoomNum    = data[0xe5];
                record.BattlesWon = data[0xe6];
                record.Unknown5   = BitConverter.ToUInt64(data, 0xe7);

                // todo: Do we want to store their record anyway if they lost the first round?
                if (record.BattlesWon > 0)
                {
                    Database.Instance.BattleTowerUpdateRecord4(record);
                }
                if (record.BattlesWon == 7)
                {
                    Database.Instance.BattleTowerAddLeader4(record);
                }

                response.Write(new byte[] { 0x01, 0x00 }, 0, 2);
            } break;

                #endregion
            }
        }
Ejemplo n.º 2
0
        public override void ProcessGamestatsRequest(byte[] data, MemoryStream response, string url, int pid, HttpContext context, GamestatsSession session)
        {
            {
                BanStatus ban = BanHelper.GetBanStatus(pid, IpAddressHelper.GetIpAddress(context.Request), Generations.Generation4);
                if (ban != null && ban.Level > BanLevels.Restricted)
                {
                    ShowError(context, 403);
                    return;
                }
            }
            Pokedex.Pokedex pokedex = AppStateHelper.Pokedex(context.Application);

            switch (url)
            {
            default:
                SessionManager.Remove(session);

                // unrecognized page url
                ShowError(context, 404);
                return;

                #region Common
            // Called during startup. Seems to contain trainer profile stats.
            case "/pokemondpds/common/setProfile.asp":
            {
                SessionManager.Remove(session);

                if (data.Length != 100)
                {
                    ShowError(context, 400);
                    return;
                }

#if !DEBUG
                try
                {
#endif
                byte[] profileBinary = new byte[100];
                Array.Copy(data, 0, profileBinary, 0, 100);
                TrainerProfile4 profile = new TrainerProfile4(pid, profileBinary, IpAddressHelper.GetIpAddress(context.Request));
                Database.Instance.GamestatsSetProfile4(profile);
#if !DEBUG
            }
                catch { }
#endif
                short clientSecret = BitConverter.ToInt16(data, 96);
                short mailSecret   = BitConverter.ToInt16(data, 98);

                // response:
                // 4 bytes of response code A
                // 4 bytes of response code B
                // Response code A values:
                // 0: Continues normally.
                // 1: The data was corrupted. It could not be sent.
                // 2: The server is undergoing maintenance. Please connect again later.
                // 3: BSOD
                if (mailSecret == -1)
                {
                    // Register wii mail
                    // Response code B values:
                    // 0: There was a communication error.
                    // 1: The Registration Code has been sent to your Wii console. Please enter the Registration Code.
                    // 2: There was an error while attempting to send an authentication Wii message.
                    // 3: There was a communication error.
                    // 4: BSOD
                    response.Write(new byte[] { 0x00, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00 },
                                   0, 8);
                }
                else if (mailSecret != 0 || clientSecret != 0)
                {
                    // Send wii mail confirmation code OR GTS when mail is configured (we can't tell them apart T__T)
                    // (todo: We could use database to tell them apart.
                    // If the previously stored profile has mailSecret == -1 then this is a wii mail confirmation.
                    // If the previously stored profile has mailSecret == this mailSecret then this is GTS.)
                    // Response code B values:
                    // 0: Your Wii Number has been registered.
                    // 1: There was a communication error.
                    // 2: There was a communication error.
                    // 3: Incorrect Registration Code.
                    // 4: BSOD
                    response.Write(new byte[] { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
                                   0, 8);
                }
                else
                {
                    // GTS
                    // Response code B values:
                    // 0: Continues normally
                    // 1: There was a communication error.
                    // 2: There was a communication error.
                    // 3: There was a Wii message authentication error.
                    // 4: BSOD
                    response.Write(new byte[] { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
                                   0, 8);
                }
            }
                break;
                #endregion

                #region GTS
            // Called during startup. Unknown purpose.
            case "/pokemondpds/worldexchange/info.asp":
            {
                SessionManager.Remove(session);

                // todo: find out the meaning of this request.
                // is it simply done to check whether the GTS is online?

                var ip = IpAddressHelper.GetIpAddress(context.Request);
                Database.Instance.GamestatsBumpProfile4(pid, ip);

                response.Write(new byte[] { 0x01, 0x00 }, 0, 2);
            } break;

            // Called during startup and when you check your pokemon's status.
            case "/pokemondpds/worldexchange/result.asp":
            {
                SessionManager.Remove(session);

                /* After the above step(s) or performing any of
                 * the tasks below other than searching, the game
                 * makes a request to /pokemondpds/worldexchange/result.asp.
                 * If the game has had a Pokémon sent to it via a trade,
                 * the server responds with the entire encrypted Pokémon
                 * save struct. Otherwise, if there is a Pokémon deposited
                 * in the GTS, it responds with 0x0004; if not, it responds
                 * with 0x0005. */

                GtsRecord4 record = Database.Instance.GtsDataForUser4(pokedex, pid);

                if (record == null)
                {
                    // No pokemon in the system
                    response.Write(new byte[] { 0x05, 0x00 }, 0, 2);
                }
                else if (record.IsExchanged > 0)
                {
                    // traded pokemon arriving!!!
                    response.Write(record.Save(), 0, 292);
                }
                else
                {
                    // my existing pokemon is in the system, untraded
                    response.Write(new byte[] { 0x04, 0x00 }, 0, 2);
                }

                // other responses:
                // 0-2 causes a BSOD but it flashes siezure. Scary
                // 3 causes it to be "checking GTS's status" forever.
                // 6 is also the flashy BSOD. So probably all invalid values do that.
            } break;

            // Called after result.asp returns 4 when you check your pokemon's status
            case "/pokemondpds/worldexchange/get.asp":
            {
                SessionManager.Remove(session);

                // this is only called if result.asp returned 4.
                // todo: what does this do if the contained pokemon is traded??

                GtsRecord4 record = Database.Instance.GtsDataForUser4(pokedex, pid);

                if (record == null)
                {
                    // No pokemon in the system
                    // what do here?
                    ShowError(context, 403);
                    return;
                }
                else
                {
                    // just write the record whether traded or not...
                    response.Write(record.Save(), 0, 292);
                }
            } break;

            // Called after result.asp returns an inbound pokemon record to delete it
            case "/pokemondpds/worldexchange/delete.asp":
            {
                SessionManager.Remove(session);

                GtsRecord4 record = Database.Instance.GtsDataForUser4(pokedex, pid);
                if (record == null)
                {
                    response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                }
                else if (record.IsExchanged > 0)
                {
                    // delete the arrived pokemon from the system
                    // todo: add transactions
                    // todo: log the successful trade?
                    // (either here or when the trade is done)
                    bool success = Database.Instance.GtsDeletePokemon4(pid);
                    if (success)
                    {
                        response.Write(new byte[] { 0x01, 0x00 }, 0, 2);
                    }
                    else
                    {
                        response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                    }
                }
                else
                {
                    // own pokemon is there, fail. Use return.asp instead.
                    response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                }
            } break;

            // called to delete your own pokemon after taking it back
            case "/pokemondpds/worldexchange/return.asp":
            {
                SessionManager.Remove(session);

                GtsRecord4 record = Database.Instance.GtsDataForUser4(pokedex, pid);
                if (record == null)
                {
                    response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                }
                else if (record.IsExchanged > 0)
                {
                    // a traded pokemon is there, fail. Use delete.asp instead.
                    response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                }
                else
                {
                    // delete own pokemon
                    // todo: add transactions
                    bool success = Database.Instance.GtsDeletePokemon4(pid);
                    if (success)
                    {
                        response.Write(new byte[] { 0x01, 0x00 }, 0, 2);
                    }
                    else
                    {
                        response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                    }
                }
            } break;

            // Called when you deposit a pokemon into the system.
            case "/pokemondpds/worldexchange/post.asp":
            {
                if (data.Length != 292)
                {
                    SessionManager.Remove(session);
                    ShowError(context, 400);
                    return;
                }

                // todo: add transaction
                if (Database.Instance.GtsDataForUser4(pokedex, pid) != null)
                {
                    // there's already a pokemon inside.
                    // Force the player out so they'll recheck its status.
                    SessionManager.Remove(session);
                    response.Write(new byte[] { 0x0e, 0x00 }, 0, 2);
                    break;
                }

                // keep the record in memory while we wait for post_finish.asp request
                byte[] recordBinary = new byte[292];
                Array.Copy(data, 0, recordBinary, 0, 292);
                GtsRecord4 record = new GtsRecord4(pokedex, recordBinary);
                record.IsExchanged = 0;
                if (!record.Validate())
                {
                    // hack check failed
                    SessionManager.Remove(session);

                    // responses:
                    // 0x00: Appears to start depositing? todo: test if this code leads to a normal deposit.
                    // 0x01: successful deposit
                    // 0x02-0x03: Communication error...
                    // 0x04-0x06: bsod
                    // 0x07: The GTS is very crowded now. Please try again later. (and it boots you!)
                    // 0x08-0x0d: That Pokémon may not be offered for trade!
                    // 0x0e: You were disconnected from the GTS. Returning to the reception counter.
                    // 0x0f: Blue screen of death
                    response.Write(new byte[] { 0x0c, 0x00 }, 0, 2);
                    break;
                }

                // the following two fields are blank in the uploaded record.
                // The server must provide them instead.
                record.TimeDeposited = DateTime.UtcNow;
                record.TimeExchanged = null;
                record.PID           = pid;

                session.Tag = record;
                // todo: delete any other post.asp sessions registered under this PID

                response.Write(new byte[] { 0x01, 0x00 }, 0, 2);
            } break;

            case "/pokemondpds/worldexchange/post_finish.asp":
            {
                SessionManager.Remove(session);

                if (data.Length != 8)
                {
                    ShowError(context, 400);
                    return;
                }

                // todo: these _finish requests seem to come with a magic number of 4 bytes
                // at offset 0. Find out what this is supposed to do and how to validate it.

                // find a matching session which contains our record
                GamestatsSession prevSession = SessionManager.FindSession(pid, "/pokemondpds/worldexchange/post.asp");
                if (prevSession == null)
                {
                    response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                    return;
                }

                SessionManager.Remove(prevSession);
                if (prevSession.Tag == null)
                {
                    response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                    return;
                }
                AssertHelper.Assert(prevSession.Tag is GtsRecord4);
                GtsRecord4 record = (GtsRecord4)prevSession.Tag;

                if (Database.Instance.GtsDepositPokemon4(record))
                {
                    response.Write(new byte[] { 0x01, 0x00 }, 0, 2);
                }
                else
                {
                    response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                }
            } break;

            // the search request has a funny bit string request of search terms
            // and just returns a chunk of records end to end.
            case "/pokemondpds/worldexchange/search.asp":
            {
                SessionManager.Remove(session);

                if (data.Length < 7 || data.Length > 8)
                {
                    ShowError(context, 400);
                    return;
                }

                ushort species = BitConverter.ToUInt16(data, 0);
                if (species < 1)
                {
                    ShowError(context, 400);
                    return;
                }

                int resultsCount = (int)data[6];
                if (resultsCount < 1)
                {
                    break;                       // optimize away requests for no rows
                }
                Genders gender   = (Genders)data[2];
                byte    minLevel = data[3];
                byte    maxLevel = data[4];
                // byte 5 unknown
                byte country = 0;
                if (data.Length > 7)
                {
                    country = data[7];
                }

                if (resultsCount > 7)
                {
                    resultsCount = 7;                       // stop DDOS
                }
                GtsRecord4[] records = Database.Instance.GtsSearch4(pokedex, pid, species, gender, minLevel, maxLevel, country, resultsCount);
                foreach (GtsRecord4 record in records)
                {
                    response.Write(record.Save(), 0, 292);
                }

                Database.Instance.GtsSetLastSearch4(pid);
            } break;

            // the exchange request uploads a record of the exchangee pokemon
            // plus the desired PID to trade for at the very end.
            case "/pokemondpds/worldexchange/exchange.asp":
            {
                if (data.Length != 296)
                {
                    SessionManager.Remove(session);
                    ShowError(context, 400);
                    return;
                }

                byte[] uploadData = new byte[292];
                Array.Copy(data, 0, uploadData, 0, 292);
                GtsRecord4 upload = new GtsRecord4(pokedex, uploadData);
                upload.IsExchanged = 0;
                int        targetPid  = BitConverter.ToInt32(data, 292);
                GtsRecord4 result     = Database.Instance.GtsDataForUser4(pokedex, targetPid);
                DateTime?  searchTime = Database.Instance.GtsGetLastSearch4(pid);

                if (result == null || searchTime == null ||
                    result.TimeDeposited > (DateTime)searchTime ||     // If this condition is met, it means the pokemon in the system is DIFFERENT from the one the user is trying to trade for, ie. it was deposited AFTER the user did their search. The one the user wants was either taken back or traded.
                    result.IsExchanged != 0)
                {
                    // Pokémon is traded (or was never here to begin with)
                    SessionManager.Remove(session);
                    response.Write(new byte[] { 0x02, 0x00 }, 0, 2);
                    break;
                }

                // enforce request requirements server side
                if (!upload.Validate() || !upload.CanTrade(result))
                {
                    // todo: find the correct codes for these
                    SessionManager.Remove(session);

                    // responses:
                    // 0x00-0x01: bsod
                    // 0x02: Unfortunately, it was traded to another Trainer.
                    // 0x03-0x07: bsod
                    // 0x08-0x0d: That Pokémon may not be offered for trade!
                    // 0x0e: You were disconnected from the GTS. Returning to the reception counter.
                    // 0x0f: bsod
                    response.Write(new byte[] { 0x0c, 0x00 }, 0, 2);
                    return;
                }

                // uncomment these two lines if you're replaying gamestats requests and need to skip the random token
                //session = new GamestatsSession(this.GameId, this.Salt, pid, "/pokemondpds/worldexchange/exchange.asp");
                //SessionManager.Add(session);

                object[] tag = new GtsRecord4[2];
                tag[0]      = upload;
                tag[1]      = result;
                session.Tag = tag;

                GtsRecord4 tradedResult = result.Clone();
                tradedResult.FlagTraded(upload);     // only real purpose is to generate a proper response

                // todo: we need a mechanism to "reserve" a pokemon being traded at this
                // point in the process, but be able to relinquish it if exchange_finish
                // never happens.
                // Currently, if two people try to take the same pokemon, it will appear
                // to work for both but then fail for the second after they've saved
                // their game. This causes a hard crash and a "save file is corrupt,
                // "previous will be loaded" error when restarting.
                // the reservation can be done in application state and has no reason
                // to touch the database. (exchange_finish won't work anyway if application
                // state is lost.)

                // I also have a hunch that failure to send the exchange_finish request
                // is what causes the notorious GTS glitch where a pokemon is listed
                // under the wrong species and you can't trade it

                response.Write(result.Save(), 0, 292);
            } break;

            case "/pokemondpds/worldexchange/exchange_finish.asp":
            {
                //if (session != null)
                SessionManager.Remove(session);

                if (data.Length != 8)
                {
                    ShowError(context, 400);
                    return;
                }

                // find a matching session which contains our record
                GamestatsSession prevSession = SessionManager.FindSession(pid, "/pokemondpds/worldexchange/exchange.asp");
                if (prevSession == null)
                {
                    response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                    return;
                }

                SessionManager.Remove(prevSession);
                if (prevSession.Tag == null)
                {
                    response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                    return;
                }
                AssertHelper.Assert(prevSession.Tag is GtsRecord4[]);
                GtsRecord4[] tag = (GtsRecord4[])prevSession.Tag;
                AssertHelper.Assert(tag.Length == 2);

                GtsRecord4 upload = tag[0];
                GtsRecord4 result = tag[1];

                if (Database.Instance.GtsTradePokemon4(upload, result, pid))
                {
                    response.Write(new byte[] { 0x01, 0x00 }, 0, 2);
                }
                else
                {
                    response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
                }
            } break;
                #endregion

                #region Battle Tower
            case "/pokemondpds/battletower/info.asp":
                SessionManager.Remove(session);

                // Probably an availability/status code.
                Database.Instance.GamestatsBumpProfile4(pid, IpAddressHelper.GetIpAddress(context.Request));

                // Response codes:
                // 0x00: BSOD
                // 0x01: Continues normally
                // 0x02: BSOD
                // 0x03: The Wi-Fi Battle Tower is currently undergoing maintenance. Please try again later.
                // 0x04: The Wi-Fi Battle Tower is very crowded. Please try again later.
                // 0x05: Unable to connect to the Wi-Fi Battle Tower. Returning to the reception counter.
                // 0x06: BSOD
                response.Write(new byte[] { 0x01, 0x00 }, 0, 2);
                break;

            case "/pokemondpds/battletower/roomnum.asp":
                SessionManager.Remove(session);

                //byte rank = data[0x00];
                response.Write(new byte[] { 0x32, 0x00 }, 0, 2);
                break;

            case "/pokemondpds/battletower/download.asp":
            {
                SessionManager.Remove(session);

                if (data.Length != 2)
                {
                    ShowError(context, 400);
                    return;
                }

                byte rank    = data[0x00];
                byte roomNum = data[0x01];

                if (rank > 9 || roomNum > 49)
                {
                    ShowError(context, 400);
                    return;
                }

                BattleTowerRecord4[]  opponents     = Database.Instance.BattleTowerGetOpponents4(pokedex, pid, rank, roomNum);
                BattleTowerProfile4[] leaders       = Database.Instance.BattleTowerGetLeaders4(pokedex, rank, roomNum);
                BattleTowerRecord4[]  fakeOpponents = FakeOpponentGenerator4.GenerateFakeOpponents(7 - opponents.Length);

                foreach (BattleTowerRecord4 record in fakeOpponents)
                {
                    response.Write(record.Save(), 0, 228);
                }

                foreach (BattleTowerRecord4 record in opponents)
                {
                    response.Write(record.Save(), 0, 228);
                }

                foreach (BattleTowerProfile4 leader in leaders)
                {
                    response.Write(leader.Save(), 0, 34);
                }

                if (leaders.Length < 30)
                {
                    byte[] fakeLeader = new BattleTowerProfile4
                                        (
                        new EncodedString4("-----", 16),
                        Versions.Platinum, Languages.English,
                        0, 0, 0x00000000, new TrendyPhrase4(5, 0, 0, 0), 0, 0
                                        ).Save();

                    for (int x = leaders.Length; x < 30; x++)
                    {
                        response.Write(fakeLeader, 0, 34);
                    }
                }

                // This is completely insane. The game crashes when you
                // use Check Leaders if the response arrives too fast,
                // so we artificially delay it.
                // todo: This is slower than it needs to be if the
                // database is slow to respond. We should sleep for a
                // variable time based on when the request was received.
                Thread.Sleep(500);
            } break;

            case "/pokemondpds/battletower/upload.asp":
            {
                SessionManager.Remove(session);

                if (data.Length != 239)
                {
                    ShowError(context, 400);
                    return;
                }

                BattleTowerRecord4 record = new BattleTowerRecord4(pokedex, data, 0);

                record.Rank       = data[0xe4];
                record.RoomNum    = data[0xe5];
                record.BattlesWon = data[0xe6];
                record.Unknown5   = BitConverter.ToUInt64(data, 0xe7);
                record.PID        = pid;

                foreach (var p in record.Party)
                {
                    if (!p.Validate().IsValid)
                    {
                        // Tell the client it was successful so they don't keep retrying.
                        response.Write(new byte[] { 0x01, 0x00 }, 0, 2);
                        return;
                    }
                }

                // todo: Do we want to store their record anyway if they lost the first round?
                if (record.BattlesWon > 0)
                {
                    Database.Instance.BattleTowerUpdateRecord4(record);
                }
                if (record.BattlesWon == 7)
                {
                    Database.Instance.BattleTowerAddLeader4(record);
                }

                // List of responses:
                // 0x00: BSOD
                // 0x01: Uploads successfully
                // 0x02: That number cannot be specified for the Wi-Fi Battle Tower.
                // 0x03: BSOD
                // 0x04: The Wi-Fi Battle Tower is very crowded. Please try again later.
                // 0x05: Unable to connect to the Wi-Fi Battle Tower. Returning to the reception counter.
                // 0x06: BSOD
                // 0x07: BSOD
                // 0x08: BSOD
                response.Write(new byte[] { 0x01, 0x00 }, 0, 2);
            } break;

                #endregion
            }
        }