public GtsSession4 FindSession4(int pid, String url)
{
// todo: keep a hash table of pids that maps them onto session objects
GtsSession4 result = null;
foreach (GtsSession4 sess in Sessions4.Values)
{
if (sess.PID == pid && sess.URL == url)
{
if (result != null)
{
// todo: there's more than one matching session... delete them all.
}
return(sess); // temp until I get it to cleanup old sessions
result = sess;
}
}
return(result);
}
public void Remove(GtsSession4 session)
{
Sessions4.Remove(session.Hash);
}
public void Add(GtsSession4 session)
{
Sessions4.Add(session.Hash, session);
}
public void ProcessRequest(HttpContext context)
{
int pid;
if (context.Request.QueryString["pid"] == null ||
!Int32.TryParse(context.Request.QueryString["pid"], out pid))
{
// pid missing or bad format
Error400(context);
return;
}
if (context.Request.QueryString.Count == 1)
{
// this is a new session request
GtsSession4 session = new GtsSession4(pid, context.Request.PathInfo);
GtsSessionManager manager = GtsSessionManager.FromContext(context);
manager.Add(session);
context.Response.Write(session.Token);
return;
}
else if (context.Request.QueryString.Count == 3)
{
// this is a main request
if (context.Request.QueryString["hash"] == null ||
context.Request.QueryString["data"] == null ||
context.Request.QueryString["data"].Length < 12)
{
// arguments missing, partial check for data length.
// (Here, we require data to hold at least 7 bytes.
// In reality, it must hold at least 8, which is checked
// for below after decoding)
Error400(context);
return;
}
GtsSessionManager manager = GtsSessionManager.FromContext(context);
if (!manager.Sessions4.ContainsKey(context.Request.QueryString["hash"]))
{
// session hash not matched
Error400(context);
return;
}
GtsSession4 session = manager.Sessions4[context.Request.QueryString["hash"]];
byte[] data;
try
{
data = GtsSession4.DecryptData(context.Request.QueryString["data"]);
if (data.Length < 4)
{
// data too short to contain a pid
// We check for 4 bytes, not 8, since the decrypt seed
// isn't included in DecryptData's result.
Error400(context);
return;
}
}
catch (FormatException)
{
// data too short to contain a checksum,
// base64 format errors
Error400(context);
return;
}
int pid2 = BitConverter.ToInt32(data, 0);
if (pid2 != pid)
{
// packed pid doesn't match ?pid=
Error400(context);
return;
}
Stream response = context.Response.OutputStream;
switch (session.URL)
{
default:
manager.Remove(session);
// unrecognized page url
// should be error 404 once we're done debugging
context.Response.Write("Almost there. Your path is:\n");
context.Response.Write(session.URL);
return;
// Called during startup. Unknown purpose.
case "/worldexchange/info.asp":
manager.Remove(session);
// todo: find out the meaning of this request.
// is it simply done to check whether the GTS is online?
response.Write(new byte[] { 0x01, 0x00 }, 0, 2);
break;
// Called during startup. Seems to contain trainer profile stats.
case "/common/setProfile.asp":
manager.Remove(session);
// todo: Figure out what fun stuff is contained in this blob!
response.Write(new byte[]
{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
0, 8);
break;
// Called during startup and when you check your pokemon's status.
case "/worldexchange/result.asp":
{
manager.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 = DataAbstract.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);
}
} break;
// Called after result.asp returns 4 when you check your pokemon's status
case "/worldexchange/get.asp":
{
manager.Remove(session);
// this is only called if result.asp returned 4.
// todo: what does this do if the contained pokemon is traded??
GtsRecord4 record = DataAbstract.Instance.GtsDataForUser4(pid);
if (record == null)
{
// No pokemon in the system
// what do here?
}
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 "/worldexchange/delete.asp":
{
manager.Remove(session);
GtsRecord4 record = DataAbstract.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 = DataAbstract.Instance.GtsDeletePokemon4(pid);
if (success)
{
manager.RefreshStats();
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 "/worldexchange/return.asp":
{
manager.Remove(session);
GtsRecord4 record = DataAbstract.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 = DataAbstract.Instance.GtsDeletePokemon4(pid);
if (success)
{
manager.RefreshStats();
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 "/worldexchange/post.asp":
{
if (data.Length != 296)
{
manager.Remove(session);
Error400(context);
return;
}
// todo: add transaction
if (DataAbstract.Instance.GtsDataForUser4(pid) != null)
{
// there's already a pokemon inside
manager.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, 4, recordBinary, 0, 292);
GtsRecord4 record = new GtsRecord4(recordBinary);
if (!record.Validate())
{
// hack check failed
manager.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.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 "/worldexchange/post_finish.asp":
{
manager.Remove(session);
if (data.Length != 12)
{
Error400(context);
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
GtsSession4 prevSession = manager.FindSession4(pid, "/worldexchange/post.asp");
manager.Remove(prevSession);
AssertHelper.Assert(prevSession.Tag is GtsRecord4);
GtsRecord4 record = (GtsRecord4)prevSession.Tag;
if (DataAbstract.Instance.GtsDepositPokemon4(record))
{
manager.RefreshStats();
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 "/worldexchange/search.asp":
{
manager.Remove(session);
if (data.Length < 11 || data.Length > 12)
{
Error400(context);
return;
}
ushort species = BitConverter.ToUInt16(data, 4);
if (species < 1)
{
Error400(context);
return;
}
int resultsCount = (int)data[10];
if (resultsCount < 1)
{
break; // optimize away requests for no rows
}
Genders gender = (Genders)data[6];
byte minLevel = data[7];
byte maxLevel = data[8];
// byte 9 unknown
byte country = 0;
if (data.Length > 11)
{
country = data[11];
}
if (resultsCount > 7)
{
resultsCount = 7; // stop DDOS
}
GtsRecord4[] records = DataAbstract.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 "/worldexchange/exchange.asp":
{
if (data.Length != 300)
{
manager.Remove(session);
Error400(context);
return;
}
byte[] uploadData = new byte[292];
Array.Copy(data, 4, uploadData, 0, 292);
GtsRecord4 upload = new GtsRecord4(uploadData);
int targetPid = BitConverter.ToInt32(data, 296);
GtsRecord4 result = DataAbstract.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.
manager.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
manager.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 "/worldexchange/exchange_finish.asp":
{
manager.Remove(session);
if (data.Length != 12)
{
Error400(context);
return;
}
// find a matching session which contains our record
GtsSession4 prevSession = manager.FindSession4(pid, "/worldexchange/exchange.asp");
manager.Remove(prevSession);
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 (DataAbstract.Instance.GtsTradePokemon4(upload, result))
{
manager.RefreshStats();
response.Write(new byte[] { 0x01, 0x00 }, 0, 2);
}
else
{
response.Write(new byte[] { 0x00, 0x00 }, 0, 2);
}
} break;
}
}
else
{
// wrong number of querystring arguments
Error400(context);
}
}
