Modules/IPStack/tcp.c

   1 /*
   2  * Acess2 IP Stack
   3  * - TCP Handling
   4  */
   5 #define DEBUG   1
   6 #include "ipstack.h"
   7 #include "ipv4.h"
   8 #include "tcp.h"
   9
  10 #define USE_SELECT      1
  11
  12 #define TCP_MIN_DYNPORT 0xC000
  13 #define TCP_MAX_HALFOPEN        1024    // Should be enough
  14
  15 #define TCP_MAX_PACKET_SIZE     1024
  16 #define TCP_WINDOW_SIZE 0x2000
  17 #define TCP_RECIEVE_BUFFER_SIZE 0x4000
  18
  19 // === PROTOTYPES ===
  20 void    TCP_Initialise();
  21 void    TCP_StartConnection(tTCPConnection *Conn);
  22 void    TCP_SendPacket(tTCPConnection *Conn, size_t Length, tTCPHeader *Data);
  23 void    TCP_GetPacket(tInterface *Interface, void *Address, int Length, void *Buffer);
  24 void    TCP_INT_HandleConnectionPacket(tTCPConnection *Connection, tTCPHeader *Header, int Length);
  25 void    TCP_INT_AppendRecieved(tTCPConnection *Connection, tTCPStoredPacket *Ptk);
  26 void    TCP_INT_UpdateRecievedFromFuture(tTCPConnection *Connection);
  27 Uint16  TCP_GetUnusedPort();
  28  int    TCP_AllocatePort(Uint16 Port);
  29  int    TCP_DeallocatePort(Uint16 Port);
  30 // --- Server
  31 tVFS_Node       *TCP_Server_Init(tInterface *Interface);
  32 char    *TCP_Server_ReadDir(tVFS_Node *Node, int Pos);
  33 tVFS_Node       *TCP_Server_FindDir(tVFS_Node *Node, const char *Name);
  34  int    TCP_Server_IOCtl(tVFS_Node *Node, int ID, void *Data);
  35 void    TCP_Server_Close(tVFS_Node *Node);
  36 // --- Client
  37 tVFS_Node       *TCP_Client_Init(tInterface *Interface);
  38 Uint64  TCP_Client_Read(tVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer);
  39 Uint64  TCP_Client_Write(tVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer);
  40  int    TCP_Client_IOCtl(tVFS_Node *Node, int ID, void *Data);
  41 void    TCP_Client_Close(tVFS_Node *Node);
  42 // --- Helpers
  43  int    WrapBetween(Uint32 Lower, Uint32 Value, Uint32 Higher, Uint32 MaxValue);
  44
  45 // === TEMPLATES ===
  46 tSocketFile     gTCP_ServerFile = {NULL, "tcps", TCP_Server_Init};
  47 tSocketFile     gTCP_ClientFile = {NULL, "tcpc", TCP_Client_Init};
  48
  49 // === GLOBALS ===
  50  int    giTCP_NumHalfopen = 0;
  51 tShortSpinlock  glTCP_Listeners;
  52 tTCPListener    *gTCP_Listeners;
  53 tShortSpinlock  glTCP_OutbountCons;
  54 tTCPConnection  *gTCP_OutbountCons;
  55 Uint32  gaTCP_PortBitmap[0x800];
  56  int    giTCP_NextOutPort = TCP_MIN_DYNPORT;
  57
  58 // === CODE ===
  59 /**
  60  * \brief Initialise the TCP Layer
  61  *
  62  * Registers the client and server files and the GetPacket callback
  63  */
  64 void TCP_Initialise()
  65 {
  66         IPStack_AddFile(&gTCP_ServerFile);
  67         IPStack_AddFile(&gTCP_ClientFile);
  68         IPv4_RegisterCallback(IP4PROT_TCP, TCP_GetPacket);
  69 }
  70
  71 /**
  72  * \brief Sends a packet from the specified connection, calculating the checksums
  73  * \param Conn  Connection
  74  * \param Length        Length of data
  75  * \param Data  Packet data (cast as a TCP Header)
  76  */
  77 void TCP_SendPacket( tTCPConnection *Conn, size_t Length, tTCPHeader *Data )
  78 {
  79         size_t  buflen;
  80         Uint32  *buf;
  81         switch( Conn->Interface->Type )
  82         {
  83         case 4: // Append IPv4 Pseudo Header
  84                 buflen = 4 + 4 + 4 + ((Length+1)&~1);
  85                 buf = malloc( buflen );
  86                 buf[0] = ((tIPv4*)Conn->Interface->Address)->L;
  87                 buf[1] = Conn->RemoteIP.v4.L;
  88                 buf[2] = (htons(Length)<<16) | (6<<8) | 0;
  89                 Data->Checksum = 0;
  90                 memcpy( &buf[3], Data, Length );
  91                 Data->Checksum = htons( IPv4_Checksum( buf, buflen ) );
  92                 free(buf);
  93                 IPv4_SendPacket(Conn->Interface, Conn->RemoteIP.v4, IP4PROT_TCP, 0, Length, Data);
  94                 break;
  95         }
  96 }
  97
  98 /**
  99  * \brief Handles a packet from the IP Layer
 100  * \param Interface     Interface the packet arrived from
 101  * \param Address       Pointer to the addres structure
 102  * \param Length        Size of packet in bytes
 103  * \param Buffer        Packet data
 104  */
 105 void TCP_GetPacket(tInterface *Interface, void *Address, int Length, void *Buffer)
 106 {
 107         tTCPHeader      *hdr = Buffer;
 108         tTCPListener    *srv;
 109         tTCPConnection  *conn;
 110
 111         Log_Log("TCP", "TCP_GetPacket: SourcePort = %i, DestPort = %i",
 112                 ntohs(hdr->SourcePort), ntohs(hdr->DestPort));
 113 /*
 114         Log_Log("TCP", "TCP_GetPacket: SequenceNumber = 0x%x", ntohl(hdr->SequenceNumber));
 115         Log_Log("TCP", "TCP_GetPacket: AcknowlegementNumber = 0x%x", ntohl(hdr->AcknowlegementNumber));
 116         Log_Log("TCP", "TCP_GetPacket: DataOffset = %i", hdr->DataOffset >> 4);
 117         Log_Log("TCP", "TCP_GetPacket: WindowSize = %i", htons(hdr->WindowSize));
 118         Log_Log("TCP", "TCP_GetPacket: Checksum = 0x%x", htons(hdr->Checksum));
 119         Log_Log("TCP", "TCP_GetPacket: UrgentPointer = 0x%x", htons(hdr->UrgentPointer));
 120 */
 121         Log_Log("TCP", "TCP_GetPacket: Flags = %s%s%s%s%s%s%s%s",
 122                 (hdr->Flags & TCP_FLAG_CWR) ? "CWR " : "",
 123                 (hdr->Flags & TCP_FLAG_ECE) ? "ECE " : "",
 124                 (hdr->Flags & TCP_FLAG_URG) ? "URG " : "",
 125                 (hdr->Flags & TCP_FLAG_ACK) ? "ACK " : "",
 126                 (hdr->Flags & TCP_FLAG_PSH) ? "PSH " : "",
 127                 (hdr->Flags & TCP_FLAG_RST) ? "RST " : "",
 128                 (hdr->Flags & TCP_FLAG_SYN) ? "SYN " : "",
 129                 (hdr->Flags & TCP_FLAG_FIN) ? "FIN " : ""
 130                 );
 131
 132         if( Length > (hdr->DataOffset >> 4)*4 )
 133         {
 134                 Log_Log("TCP", "TCP_GetPacket: SequenceNumber = 0x%x", ntohl(hdr->SequenceNumber));
 135                 Debug_HexDump(
 136                         "[TCP  ] Packet Data = ",
 137                         (Uint8*)hdr + (hdr->DataOffset >> 4)*4,
 138                         Length - (hdr->DataOffset >> 4)*4
 139                         );
 140         }
 141
 142         // Check Servers
 143         {
 144                 for( srv = gTCP_Listeners; srv; srv = srv->Next )
 145                 {
 146                         // Check if the server is active
 147                         if(srv->Port == 0)      continue;
 148                         // Check the interface
 149                         if(srv->Interface && srv->Interface != Interface)       continue;
 150                         // Check the destination port
 151                         if(srv->Port != htons(hdr->DestPort))   continue;
 152
 153                         Log_Log("TCP", "TCP_GetPacket: Matches server %p", srv);
 154                         // Is this in an established connection?
 155                         for( conn = srv->Connections; conn; conn = conn->Next )
 156                         {
 157                                 Log_Log("TCP", "TCP_GetPacket: conn->Interface(%p) == Interface(%p)",
 158                                         conn->Interface, Interface);
 159                                 // Check that it is coming in on the same interface
 160                                 if(conn->Interface != Interface)        continue;
 161
 162                                 // Check Source Port
 163                                 Log_Log("TCP", "TCP_GetPacket: conn->RemotePort(%i) == hdr->SourcePort(%i)",
 164                                         conn->RemotePort, ntohs(hdr->SourcePort));
 165                                 if(conn->RemotePort != ntohs(hdr->SourcePort))  continue;
 166
 167                                 // Check Source IP
 168                                 if(conn->Interface->Type == 6 && !IP6_EQU(conn->RemoteIP.v6, *(tIPv6*)Address))
 169                                         continue;
 170                                 if(conn->Interface->Type == 4 && !IP4_EQU(conn->RemoteIP.v4, *(tIPv4*)Address))
 171                                         continue;
 172
 173                                 Log_Log("TCP", "TCP_GetPacket: Matches connection %p", conn);
 174                                 // We have a response!
 175                                 TCP_INT_HandleConnectionPacket(conn, hdr, Length);
 176
 177                                 return;
 178                         }
 179
 180                         Log_Log("TCP", "TCP_GetPacket: Opening Connection");
 181                         // Open a new connection (well, check that it's a SYN)
 182                         if(hdr->Flags != TCP_FLAG_SYN) {
 183                                 Log_Log("TCP", "TCP_GetPacket: Packet is not a SYN");
 184                                 return ;
 185                         }
 186
 187                         // TODO: Check for halfopen max
 188
 189                         conn = calloc(1, sizeof(tTCPConnection));
 190                         conn->State = TCP_ST_SYN_RCVD;
 191                         conn->LocalPort = srv->Port;
 192                         conn->RemotePort = ntohs(hdr->SourcePort);
 193                         conn->Interface = Interface;
 194
 195                         switch(Interface->Type)
 196                         {
 197                         case 4: conn->RemoteIP.v4 = *(tIPv4*)Address;   break;
 198                         case 6: conn->RemoteIP.v6 = *(tIPv6*)Address;   break;
 199                         }
 200
 201                         conn->RecievedBuffer = RingBuffer_Create( TCP_RECIEVE_BUFFER_SIZE );
 202
 203                         conn->NextSequenceRcv = ntohl( hdr->SequenceNumber ) + 1;
 204                         conn->NextSequenceSend = rand();
 205
 206                         // Create node
 207                         conn->Node.NumACLs = 1;
 208                         conn->Node.ACLs = &gVFS_ACL_EveryoneRW;
 209                         conn->Node.ImplPtr = conn;
 210                         conn->Node.ImplInt = srv->NextID ++;
 211                         conn->Node.Read = TCP_Client_Read;
 212                         conn->Node.Write = TCP_Client_Write;
 213                         //conn->Node.Close = TCP_SrvConn_Close;
 214
 215                         // Hmm... Theoretically, this lock will never have to wait,
 216                         // as the interface is locked to the watching thread, and this
 217                         // runs in the watching thread. But, it's a good idea to have
 218                         // it, just in case
 219                         // Oh, wait, there is a case where a wildcard can be used
 220                         // (srv->Interface == NULL) so having the lock is a good idea
 221                         SHORTLOCK(&srv->lConnections);
 222                         if( !srv->Connections )
 223                                 srv->Connections = conn;
 224                         else
 225                                 srv->ConnectionsTail->Next = conn;
 226                         srv->ConnectionsTail = conn;
 227                         if(!srv->NewConnections)
 228                                 srv->NewConnections = conn;
 229                         SHORTREL(&srv->lConnections);
 230
 231                         // Send the SYN ACK
 232                         hdr->Flags |= TCP_FLAG_ACK;
 233                         hdr->AcknowlegementNumber = htonl(conn->NextSequenceRcv);
 234                         hdr->SequenceNumber = htonl(conn->NextSequenceSend);
 235                         hdr->DestPort = hdr->SourcePort;
 236                         hdr->SourcePort = htons(srv->Port);
 237                         hdr->DataOffset = (sizeof(tTCPHeader)/4) << 4;
 238                         TCP_SendPacket( conn, sizeof(tTCPHeader), hdr );
 239                         conn->NextSequenceSend ++;
 240                         return ;
 241                 }
 242         }
 243
 244
 245         // Check Open Connections
 246         {
 247                 for( conn = gTCP_OutbountCons; conn; conn = conn->Next )
 248                 {
 249                         // Check that it is coming in on the same interface
 250                         if(conn->Interface != Interface)        continue;
 251
 252                         // Check Source Port
 253                         if(conn->RemotePort != ntohs(hdr->SourcePort))  continue;
 254
 255                         // Check Source IP
 256                         if(conn->Interface->Type == 6 && !IP6_EQU(conn->RemoteIP.v6, *(tIPv6*)Address))
 257                                 continue;
 258                         if(conn->Interface->Type == 4 && !IP4_EQU(conn->RemoteIP.v4, *(tIPv4*)Address))
 259                                 continue;
 260
 261                         TCP_INT_HandleConnectionPacket(conn, hdr, Length);
 262                         return ;
 263                 }
 264         }
 265
 266         Log_Log("TCP", "TCP_GetPacket: No Match");
 267 }
 268
 269 /**
 270  * \brief Handles a packet sent to a specific connection
 271  * \param Connection    TCP Connection pointer
 272  * \param Header        TCP Packet pointer
 273  * \param Length        Length of the packet
 274  */
 275 void TCP_INT_HandleConnectionPacket(tTCPConnection *Connection, tTCPHeader *Header, int Length)
 276 {
 277         tTCPStoredPacket        *pkt;
 278          int    dataLen;
 279
 280         // Silently drop once finished
 281         // TODO: Check if this needs to be here
 282         if( Connection->State == TCP_ST_FINISHED ) {
 283                 Log_Log("TCP", "Packet ignored - connection finnished");
 284                 return ;
 285         }
 286
 287         // Syncronise sequence values
 288         if(Header->Flags & TCP_FLAG_SYN) {
 289                 // TODO: What if the packet also has data?
 290                 Connection->NextSequenceRcv = ntohl(Header->SequenceNumber);
 291         }
 292
 293         // Ackowledge a sent packet
 294         if(Header->Flags & TCP_FLAG_ACK) {
 295                 // TODO: Process an ACKed Packet
 296                 Log_Log("TCP", "Conn %p, Sent packet 0x%x ACKed", Connection, Header->AcknowlegementNumber);
 297         }
 298
 299         // Get length of data
 300         dataLen = Length - (Header->DataOffset>>4)*4;
 301         Log_Log("TCP", "HandleConnectionPacket - dataLen = %i", dataLen);
 302
 303         //
 304         // State Machine
 305         //
 306         switch( Connection->State )
 307         {
 308         // Pre-init conneciton?
 309         case TCP_ST_CLOSED:
 310                 Log_Log("TCP", "Packets to a closed connection?!");
 311                 break;
 312
 313         // --- Init States ---
 314         // SYN sent, expecting SYN-ACK Connection Opening
 315         case TCP_ST_SYN_SENT:
 316                 if( Header->Flags & TCP_FLAG_SYN )
 317                 {
 318                         Connection->NextSequenceRcv ++;
 319                         Header->DestPort = Header->SourcePort;
 320                         Header->SourcePort = htons(Connection->LocalPort);
 321                         Header->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 322                         Header->SequenceNumber = htonl(Connection->NextSequenceSend);
 323                         Header->WindowSize = htons(TCP_WINDOW_SIZE);
 324                         Header->Flags = TCP_FLAG_ACK;
 325                         Header->DataOffset = (sizeof(tTCPHeader)/4) << 4;
 326                         TCP_SendPacket( Connection, sizeof(tTCPHeader), Header );
 327
 328                         if( Header->Flags & TCP_FLAG_ACK )
 329                         {
 330                                 Log_Log("TCP", "ACKing SYN-ACK");
 331                                 Connection->State = TCP_ST_OPEN;
 332                         }
 333                         else
 334                         {
 335                                 Log_Log("TCP", "ACKing SYN");
 336                                 Connection->State = TCP_ST_SYN_RCVD;
 337                         }
 338                 }
 339                 break;
 340
 341         // SYN-ACK sent, expecting ACK
 342         case TCP_ST_SYN_RCVD:
 343                 if( Header->Flags & TCP_FLAG_ACK )
 344                 {
 345                         // TODO: Handle max half-open limit
 346                         Connection->State = TCP_ST_OPEN;
 347                         Log_Log("TCP", "Connection fully opened");
 348                 }
 349                 break;
 350
 351         // --- Established State ---
 352         case TCP_ST_OPEN:
 353                 // - Handle State changes
 354                 //
 355                 if( Header->Flags & TCP_FLAG_FIN ) {
 356                         Log_Log("TCP", "Conn %p closed, recieved FIN, acknowledging", Connection);
 357                         VFS_MarkError(&Connection->Node, 1);
 358                         Connection->State = TCP_ST_CLOSE_WAIT;
 359                         // CLOSE WAIT requires the client to close (or does it?)
 360                         #if 0
 361
 362                         #endif
 363                 }
 364
 365                 // Check for an empty packet
 366                 if(dataLen == 0) {
 367                         if( Header->Flags == TCP_FLAG_ACK )
 368                         {
 369                                 Log_Log("TCP", "ACK only packet");
 370                                 return ;
 371                         }
 372                         Connection->NextSequenceRcv ++; // TODO: Is this right? (empty packet counts as one byte)
 373                         Log_Log("TCP", "Empty Packet, inc and ACK the current sequence number");
 374                         Header->DestPort = Header->SourcePort;
 375                         Header->SourcePort = htons(Connection->LocalPort);
 376                         Header->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 377                         Header->SequenceNumber = htonl(Connection->NextSequenceSend);
 378                         Header->Flags |= TCP_FLAG_ACK;
 379                         TCP_SendPacket( Connection, sizeof(tTCPHeader), Header );
 380                         return ;
 381                 }
 382
 383                 // NOTES:
 384                 // Flags
 385                 //    PSH - Has Data?
 386                 // /NOTES
 387
 388                 // Allocate and fill cached packet
 389                 pkt = malloc( sizeof(tTCPStoredPacket) + dataLen );
 390                 pkt->Next = NULL;
 391                 pkt->Sequence = ntohl(Header->SequenceNumber);
 392                 pkt->Length = dataLen;
 393                 memcpy(pkt->Data, (Uint8*)Header + (Header->DataOffset>>4)*4, dataLen);
 394
 395                 Log_Log("TCP", "0x%08x <= 0x%08x < 0x%08x",
 396                         Connection->NextSequenceRcv,
 397                         pkt->Sequence,
 398                         Connection->NextSequenceRcv + TCP_WINDOW_SIZE
 399                         );
 400
 401                 // Is this packet the next expected packet?
 402                 if( pkt->Sequence == Connection->NextSequenceRcv )
 403                 {
 404                         // Ooh, Goodie! Add it to the recieved list
 405                         TCP_INT_AppendRecieved(Connection, pkt);
 406                         free(pkt);
 407                         Log_Log("TCP", "0x%08x += %i", Connection->NextSequenceRcv, dataLen);
 408                         Connection->NextSequenceRcv += dataLen;
 409
 410                         // TODO: This should be moved out of the watcher thread,
 411                         // so that a single lost packet on one connection doesn't cause
 412                         // all connections on the interface to lag.
 413                         TCP_INT_UpdateRecievedFromFuture(Connection);
 414
 415                         // ACK Packet
 416                         Header->DestPort = Header->SourcePort;
 417                         Header->SourcePort = htons(Connection->LocalPort);
 418                         Header->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 419                         Header->SequenceNumber = htonl(Connection->NextSequenceSend);
 420                         Header->WindowSize = htons(TCP_WINDOW_SIZE);
 421                         Header->Flags &= TCP_FLAG_SYN;  // Eliminate all flags save for SYN
 422                         Header->Flags |= TCP_FLAG_ACK;  // Add ACK
 423                         Log_Log("TCP", "Sending ACK for 0x%08x", Connection->NextSequenceRcv);
 424                         TCP_SendPacket( Connection, sizeof(tTCPHeader), Header );
 425                         //Connection->NextSequenceSend ++;
 426                 }
 427                 // Check if the packet is in window
 428                 else if( WrapBetween(Connection->NextSequenceRcv, pkt->Sequence, Connection->NextSequenceRcv+TCP_WINDOW_SIZE, 0xFFFFFFFF) )
 429                 {
 430                         tTCPStoredPacket        *tmp, *prev = NULL;
 431
 432                         Log_Log("TCP", "We missed a packet, caching",
 433                                 pkt->Sequence, Connection->NextSequenceRcv);
 434
 435                         // No? Well, let's cache it and look at it later
 436                         SHORTLOCK( &Connection->lFuturePackets );
 437                         for(tmp = Connection->FuturePackets;
 438                                 tmp;
 439                                 prev = tmp, tmp = tmp->Next)
 440                         {
 441                                 if(tmp->Sequence >= pkt->Sequence)      break;
 442                         }
 443
 444                         // Add if before first, or sequences don't match
 445                         if( !tmp || tmp->Sequence != pkt->Sequence )
 446                         {
 447                                 if(prev)
 448                                         prev->Next = pkt;
 449                                 else
 450                                         Connection->FuturePackets = pkt;
 451                                 pkt->Next = tmp;
 452                         }
 453                         // Replace if larger
 454                         else if(pkt->Length > tmp->Length)
 455                         {
 456                                 if(prev)
 457                                         prev->Next = pkt;
 458                                 pkt->Next = tmp->Next;
 459                                 free(tmp);
 460                         }
 461                         else
 462                         {
 463                                 free(pkt);
 464                         }
 465                         SHORTREL( &Connection->lFuturePackets );
 466                 }
 467                 // Badly out of sequence packet
 468                 else
 469                 {
 470                         Log_Log("TCP", "Fully out of sequence packet (0x%08x not between 0x%08x and 0x%08x), dropped",
 471                                 pkt->Sequence, Connection->NextSequenceRcv, Connection->NextSequenceRcv+TCP_WINDOW_SIZE);
 472                         free(pkt);
 473                         // TODO: Spec says we should send an empty ACK with the current state
 474                 }
 475                 break;
 476
 477         // --- Remote close states
 478         case TCP_ST_CLOSE_WAIT:
 479
 480                 // Ignore everything, CLOSE_WAIT is terminated by the client
 481                 Log_Debug("TCP", "CLOSE WAIT - Ignoring packets");
 482
 483                 break;
 484
 485         // LAST-ACK - Waiting for the ACK of FIN (from CLOSE WAIT)
 486         case TCP_ST_LAST_ACK:
 487                 if( Header->Flags & TCP_FLAG_ACK )
 488                 {
 489                         Connection->State = TCP_ST_FINISHED;    // Connection completed
 490                         Log_Log("TCP", "LAST-ACK to CLOSED - Connection remote closed");
 491                         // TODO: Destrory the TCB
 492                 }
 493                 break;
 494
 495         // --- Local close States
 496         case TCP_ST_FIN_WAIT1:
 497                 if( Header->Flags & TCP_FLAG_FIN )
 498                 {
 499                         Connection->State = TCP_ST_CLOSING;
 500                         Log_Debug("TCP", "Conn %p closed, sent FIN and recieved FIN", Connection);
 501                         VFS_MarkError(&Connection->Node, 1);
 502
 503                         // ACK Packet
 504                         Header->DestPort = Header->SourcePort;
 505                         Header->SourcePort = htons(Connection->LocalPort);
 506                         Header->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 507                         Header->SequenceNumber = htonl(Connection->NextSequenceSend);
 508                         Header->WindowSize = htons(TCP_WINDOW_SIZE);
 509                         Header->Flags = TCP_FLAG_ACK;
 510                         TCP_SendPacket( Connection, sizeof(tTCPHeader), Header );
 511                         break ;
 512                 }
 513
 514                 // TODO: Make sure that the packet is actually ACKing the FIN
 515                 if( Header->Flags & TCP_FLAG_ACK )
 516                 {
 517                         Connection->State = TCP_ST_FIN_WAIT2;
 518                         Log_Debug("TCP", "Conn %p closed, sent FIN ACKed", Connection);
 519                         VFS_MarkError(&Connection->Node, 1);
 520                         return ;
 521                 }
 522                 break;
 523
 524         case TCP_ST_FIN_WAIT2:
 525                 if( Header->Flags & TCP_FLAG_FIN )
 526                 {
 527                         Connection->State = TCP_ST_TIME_WAIT;
 528                         Log_Debug("TCP", "FIN sent and recieved, ACKing and going into TIME WAIT %p FINWAIT-2 -> TIME WAIT", Connection);
 529                         // Send ACK
 530                         Header->DestPort = Header->SourcePort;
 531                         Header->SourcePort = htons(Connection->LocalPort);
 532                         Header->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 533                         Header->SequenceNumber = htonl(Connection->NextSequenceSend);
 534                         Header->WindowSize = htons(TCP_WINDOW_SIZE);
 535                         Header->Flags = TCP_FLAG_ACK;
 536                         TCP_SendPacket( Connection, sizeof(tTCPHeader), Header );
 537                 }
 538                 break;
 539
 540         case TCP_ST_CLOSING:
 541                 // TODO: Make sure that the packet is actually ACKing the FIN
 542                 if( Header->Flags & TCP_FLAG_ACK )
 543                 {
 544                         Connection->State = TCP_ST_TIME_WAIT;
 545                         Log_Debug("TCP", "Conn %p CLOSING -> TIME WAIT", Connection);
 546                         VFS_MarkError(&Connection->Node, 1);
 547                         return ;
 548                 }
 549                 break;
 550
 551         // --- Closed (or near closed) states) ---
 552         case TCP_ST_TIME_WAIT:
 553                 Log_Log("TCP", "Packets on Time-Wait, ignored");
 554                 break;
 555
 556         case TCP_ST_FINISHED:
 557                 Log_Log("TCP", "Packets when CLOSED, ignoring");
 558                 break;
 559
 560         //default:
 561         //      Log_Warning("TCP", "Unhandled TCP state %i", Connection->State);
 562         //      break;
 563         }
 564
 565 }
 566
 567 /**
 568  * \brief Appends a packet to the recieved list
 569  * \param Connection    Connection structure
 570  * \param Pkt   Packet structure on heap
 571  */
 572 void TCP_INT_AppendRecieved(tTCPConnection *Connection, tTCPStoredPacket *Pkt)
 573 {
 574         Mutex_Acquire( &Connection->lRecievedPackets );
 575         if(Connection->RecievedBuffer->Length + Pkt->Length > Connection->RecievedBuffer->Space )
 576         {
 577                 Log_Error("TCP", "Buffer filled, packet dropped (%s)",
 578                 //      TCP_INT_DumpConnection(Connection)
 579                         ""
 580                         );
 581                 return ;
 582         }
 583
 584         RingBuffer_Write( Connection->RecievedBuffer, Pkt->Data, Pkt->Length );
 585
 586         #if USE_SELECT
 587         VFS_MarkAvaliable(&Connection->Node, 1);
 588         #endif
 589
 590         Mutex_Release( &Connection->lRecievedPackets );
 591 }
 592
 593 /**
 594  * \brief Updates the connections recieved list from the future list
 595  * \param Connection    Connection structure
 596  *
 597  * Updates the recieved packets list with packets from the future (out
 598  * of order) packets list that are now able to be added in direct
 599  * sequence.
 600  */
 601 void TCP_INT_UpdateRecievedFromFuture(tTCPConnection *Connection)
 602 {
 603         tTCPStoredPacket        *pkt;
 604         for(;;)
 605         {
 606                 SHORTLOCK( &Connection->lFuturePackets );
 607
 608                 // Clear out duplicates from cache
 609                 // - If a packet has just been recieved, and it is expected, then
 610                 //   (since NextSequenceRcv = rcvd->Sequence + rcvd->Length) all
 611                 //   packets in cache that are smaller than the next expected
 612                 //   are now defunct.
 613                 pkt = Connection->FuturePackets;
 614                 while(pkt && pkt->Sequence < Connection->NextSequenceRcv)
 615                 {
 616                         tTCPStoredPacket        *next = pkt->Next;
 617                         free(pkt);
 618                         pkt = next;
 619                 }
 620
 621                 // If there's no packets left in cache, stop looking
 622                 if(!pkt || pkt->Sequence > Connection->NextSequenceRcv) {
 623                         SHORTREL( &Connection->lFuturePackets );
 624                         return;
 625                 }
 626
 627                 // Delete packet from future list
 628                 Connection->FuturePackets = pkt->Next;
 629
 630                 // Release list
 631                 SHORTREL( &Connection->lFuturePackets );
 632
 633                 // Looks like we found one
 634                 TCP_INT_AppendRecieved(Connection, pkt);
 635                 Connection->NextSequenceRcv += pkt->Length;
 636                 free(pkt);
 637         }
 638 }
 639
 640 /**
 641  * \fn Uint16 TCP_GetUnusedPort()
 642  * \brief Gets an unused port and allocates it
 643  */
 644 Uint16 TCP_GetUnusedPort()
 645 {
 646         Uint16  ret;
 647
 648         // Get Next outbound port
 649         ret = giTCP_NextOutPort++;
 650         while( gaTCP_PortBitmap[ret/32] & (1 << (ret%32)) )
 651         {
 652                 ret ++;
 653                 giTCP_NextOutPort++;
 654                 if(giTCP_NextOutPort == 0x10000) {
 655                         ret = giTCP_NextOutPort = TCP_MIN_DYNPORT;
 656                 }
 657         }
 658
 659         // Mark the new port as used
 660         gaTCP_PortBitmap[ret/32] |= 1 << (ret%32);
 661
 662         return ret;
 663 }
 664
 665 /**
 666  * \fn int TCP_AllocatePort(Uint16 Port)
 667  * \brief Marks a port as used
 668  */
 669 int TCP_AllocatePort(Uint16 Port)
 670 {
 671         // Check if the port has already been allocated
 672         if( gaTCP_PortBitmap[Port/32] & (1 << (Port%32)) )
 673                 return 0;
 674
 675         // Allocate
 676         gaTCP_PortBitmap[Port/32] |= 1 << (Port%32);
 677
 678         return 1;
 679 }
 680
 681 /**
 682  * \fn int TCP_DeallocatePort(Uint16 Port)
 683  * \brief Marks a port as unused
 684  */
 685 int TCP_DeallocatePort(Uint16 Port)
 686 {
 687         // Check if the port has already been allocated
 688         if( !(gaTCP_PortBitmap[Port/32] & (1 << (Port%32))) )
 689                 return 0;
 690
 691         // Allocate
 692         gaTCP_PortBitmap[Port/32] &= ~(1 << (Port%32));
 693
 694         return 1;
 695 }
 696
 697 // --- Server
 698 tVFS_Node *TCP_Server_Init(tInterface *Interface)
 699 {
 700         tTCPListener    *srv;
 701
 702         srv = malloc( sizeof(tTCPListener) );
 703
 704         if( srv == NULL ) {
 705                 Log_Warning("TCP", "malloc failed for listener (%i) bytes", sizeof(tTCPListener));
 706                 return NULL;
 707         }
 708
 709         srv->Interface = Interface;
 710         srv->Port = 0;
 711         srv->NextID = 0;
 712         srv->Connections = NULL;
 713         srv->ConnectionsTail = NULL;
 714         srv->NewConnections = NULL;
 715         srv->Next = NULL;
 716         srv->Node.Flags = VFS_FFLAG_DIRECTORY;
 717         srv->Node.Size = -1;
 718         srv->Node.ImplPtr = srv;
 719         srv->Node.NumACLs = 1;
 720         srv->Node.ACLs = &gVFS_ACL_EveryoneRW;
 721         srv->Node.ReadDir = TCP_Server_ReadDir;
 722         srv->Node.FindDir = TCP_Server_FindDir;
 723         srv->Node.IOCtl = TCP_Server_IOCtl;
 724         srv->Node.Close = TCP_Server_Close;
 725
 726         SHORTLOCK(&glTCP_Listeners);
 727         srv->Next = gTCP_Listeners;
 728         gTCP_Listeners = srv;
 729         SHORTREL(&glTCP_Listeners);
 730
 731         return &srv->Node;
 732 }
 733
 734 /**
 735  * \brief Wait for a new connection and return the connection ID
 736  * \note Blocks until a new connection is made
 737  * \param Node  Server node
 738  * \param Pos   Position (ignored)
 739  */
 740 char *TCP_Server_ReadDir(tVFS_Node *Node, int Pos)
 741 {
 742         tTCPListener    *srv = Node->ImplPtr;
 743         tTCPConnection  *conn;
 744         char    *ret;
 745
 746         ENTER("pNode iPos", Node, Pos);
 747
 748         Log_Log("TCP", "Thread %i waiting for a connection", Threads_GetTID());
 749         for(;;)
 750         {
 751                 SHORTLOCK( &srv->lConnections );
 752                 if( srv->NewConnections != NULL )       break;
 753                 SHORTREL( &srv->lConnections );
 754                 Threads_Yield();        // TODO: Sleep until poked
 755                 continue;
 756         }
 757
 758
 759         // Increment the new list (the current connection is still on the
 760         // normal list)
 761         conn = srv->NewConnections;
 762         srv->NewConnections = conn->Next;
 763
 764         SHORTREL( &srv->lConnections );
 765
 766         LOG("conn = %p", conn);
 767         LOG("srv->Connections = %p", srv->Connections);
 768         LOG("srv->NewConnections = %p", srv->NewConnections);
 769         LOG("srv->ConnectionsTail = %p", srv->ConnectionsTail);
 770
 771         ret = malloc(9);
 772         itoa(ret, conn->Node.ImplInt, 16, 8, '0');
 773         Log_Log("TCP", "Thread %i got '%s'", Threads_GetTID(), ret);
 774         LEAVE('s', ret);
 775         return ret;
 776 }
 777
 778 /**
 779  * \brief Gets a client connection node
 780  * \param Node  Server node
 781  * \param Name  Hexadecimal ID of the node
 782  */
 783 tVFS_Node *TCP_Server_FindDir(tVFS_Node *Node, const char *Name)
 784 {
 785         tTCPConnection  *conn;
 786         tTCPListener    *srv = Node->ImplPtr;
 787         char    tmp[9];
 788          int    id = atoi(Name);
 789
 790         ENTER("pNode sName", Node, Name);
 791
 792         // Sanity Check
 793         itoa(tmp, id, 16, 8, '0');
 794         if(strcmp(tmp, Name) != 0) {
 795                 LOG("'%s' != '%s' (%08x)", Name, tmp, id);
 796                 LEAVE('n');
 797                 return NULL;
 798         }
 799
 800         Log_Debug("TCP", "srv->Connections = %p", srv->Connections);
 801         Log_Debug("TCP", "srv->NewConnections = %p", srv->NewConnections);
 802         Log_Debug("TCP", "srv->ConnectionsTail = %p", srv->ConnectionsTail);
 803
 804         // Search
 805         SHORTLOCK( &srv->lConnections );
 806         for(conn = srv->Connections;
 807                 conn;
 808                 conn = conn->Next)
 809         {
 810                 LOG("conn->Node.ImplInt = %i", conn->Node.ImplInt);
 811                 if(conn->Node.ImplInt == id)    break;
 812         }
 813         SHORTREL( &srv->lConnections );
 814
 815         // If not found, ret NULL
 816         if(!conn) {
 817                 LOG("Connection %i not found", id);
 818                 LEAVE('n');
 819                 return NULL;
 820         }
 821
 822         // Return node
 823         LEAVE('p', &conn->Node);
 824         return &conn->Node;
 825 }
 826
 827 /**
 828  * \brief Handle IOCtl calls
 829  */
 830 int TCP_Server_IOCtl(tVFS_Node *Node, int ID, void *Data)
 831 {
 832         tTCPListener    *srv = Node->ImplPtr;
 833
 834         switch(ID)
 835         {
 836         case 4: // Get/Set Port
 837                 if(!Data)       // Get Port
 838                         return srv->Port;
 839
 840                 if(srv->Port)   // Wait, you can't CHANGE the port
 841                         return -1;
 842
 843                 if(!CheckMem(Data, sizeof(Uint16)))     // Sanity check
 844                         return -1;
 845
 846                 // Permissions check
 847                 if(Threads_GetUID() != 0
 848                 && *(Uint16*)Data != 0
 849                 && *(Uint16*)Data < 1024)
 850                         return -1;
 851
 852                 // TODO: Check if a port is in use
 853
 854                 // Set Port
 855                 srv->Port = *(Uint16*)Data;
 856                 if(srv->Port == 0)      // Allocate a random port
 857                         srv->Port = TCP_GetUnusedPort();
 858                 else    // Else, mark this as used
 859                         TCP_AllocatePort(srv->Port);
 860
 861                 Log_Log("TCP", "Server %p listening on port %i", srv, srv->Port);
 862
 863                 return srv->Port;
 864         }
 865         return 0;
 866 }
 867
 868 void TCP_Server_Close(tVFS_Node *Node)
 869 {
 870         free(Node->ImplPtr);
 871 }
 872
 873 // --- Client
 874 /**
 875  * \brief Create a client node
 876  */
 877 tVFS_Node *TCP_Client_Init(tInterface *Interface)
 878 {
 879         tTCPConnection  *conn = malloc( sizeof(tTCPConnection) );
 880
 881         conn->State = TCP_ST_CLOSED;
 882         conn->Interface = Interface;
 883         conn->LocalPort = -1;
 884         conn->RemotePort = -1;
 885         memset( &conn->RemoteIP, 0, sizeof(conn->RemoteIP) );
 886
 887         conn->Node.ImplPtr = conn;
 888         conn->Node.NumACLs = 1;
 889         conn->Node.ACLs = &gVFS_ACL_EveryoneRW;
 890         conn->Node.Read = TCP_Client_Read;
 891         conn->Node.Write = TCP_Client_Write;
 892         conn->Node.IOCtl = TCP_Client_IOCtl;
 893         conn->Node.Close = TCP_Client_Close;
 894
 895         conn->RecievedBuffer = RingBuffer_Create( TCP_RECIEVE_BUFFER_SIZE );
 896         #if 0
 897         conn->SentBuffer = RingBuffer_Create( TCP_SEND_BUFFER_SIZE );
 898         Semaphore_Init(conn->SentBufferSpace, 0, TCP_SEND_BUFFER_SIZE, "TCP SentBuffer", conn->Name);
 899         #endif
 900
 901         SHORTLOCK(&glTCP_OutbountCons);
 902         conn->Next = gTCP_OutbountCons;
 903         gTCP_OutbountCons = conn;
 904         SHORTREL(&glTCP_OutbountCons);
 905
 906         return &conn->Node;
 907 }
 908
 909 /**
 910  * \brief Wait for a packet and return it
 911  * \note If \a Length is smaller than the size of the packet, the rest
 912  *       of the packet's data will be discarded.
 913  */
 914 Uint64 TCP_Client_Read(tVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer)
 915 {
 916         tTCPConnection  *conn = Node->ImplPtr;
 917         size_t  len;
 918
 919         ENTER("pNode XOffset XLength pBuffer", Node, Offset, Length, Buffer);
 920         LOG("conn = %p {State:%i}", conn, conn->State);
 921
 922         // Check if connection is open
 923         while( conn->State == TCP_ST_SYN_RCVD || conn->State == TCP_ST_SYN_SENT )
 924                 Threads_Yield();
 925
 926         if( conn->State != TCP_ST_OPEN )
 927         {
 928                 Mutex_Acquire( &conn->lRecievedPackets );
 929                 len = RingBuffer_Read( Buffer, conn->RecievedBuffer, Length );
 930                 Mutex_Release( &conn->lRecievedPackets );
 931
 932                 if( len == 0 ) {
 933                         VFS_MarkAvaliable(Node, 0);
 934                         LEAVE('i', -1);
 935                         return -1;
 936                 }
 937
 938                 LEAVE('i', len);
 939                 return len;
 940         }
 941
 942         // Wait
 943         VFS_SelectNode(Node, VFS_SELECT_READ, NULL, "TCP_Client_Read");
 944
 945         // Lock list and read
 946         Mutex_Acquire( &conn->lRecievedPackets );
 947
 948         // Attempt to read all `Length` bytes
 949         len = RingBuffer_Read( Buffer, conn->RecievedBuffer, Length );
 950
 951         if( len == 0 || conn->RecievedBuffer->Length == 0 ) {
 952                 LOG("Marking as none avaliable (len = %i)", len);
 953                 VFS_MarkAvaliable(Node, 0);
 954         }
 955
 956         // Release the lock (we don't need it any more)
 957         Mutex_Release( &conn->lRecievedPackets );
 958
 959         LEAVE('i', len);
 960         return len;
 961 }
 962
 963 /**
 964  * \brief Send a data packet on a connection
 965  */
 966 void TCP_INT_SendDataPacket(tTCPConnection *Connection, size_t Length, void *Data)
 967 {
 968         char    buf[sizeof(tTCPHeader)+Length];
 969         tTCPHeader      *packet = (void*)buf;
 970
 971         packet->SourcePort = htons(Connection->LocalPort);
 972         packet->DestPort = htons(Connection->RemotePort);
 973         packet->DataOffset = (sizeof(tTCPHeader)/4)*16;
 974         packet->WindowSize = TCP_WINDOW_SIZE;
 975
 976         packet->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 977         packet->SequenceNumber = htonl(Connection->NextSequenceSend);
 978         packet->Flags = TCP_FLAG_PSH|TCP_FLAG_ACK;      // Hey, ACK if you can!
 979
 980         memcpy(packet->Options, Data, Length);
 981
 982         Log_Debug("TCP", "Send sequence 0x%08x", Connection->NextSequenceSend);
 983         Debug_HexDump("[TCP     ] TCP_INT_SendDataPacket: Data = ",
 984                 Data, Length);
 985
 986         TCP_SendPacket( Connection, sizeof(tTCPHeader)+Length, packet );
 987
 988         Connection->NextSequenceSend += Length;
 989 }
 990
 991 /**
 992  * \brief Send some bytes on a connection
 993  */
 994 Uint64 TCP_Client_Write(tVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer)
 995 {
 996         tTCPConnection  *conn = Node->ImplPtr;
 997         size_t  rem = Length;
 998
 999         ENTER("pNode XOffset XLength pBuffer", Node, Offset, Length, Buffer);
1000
1001         // Check if connection is open
1002         while( conn->State == TCP_ST_SYN_RCVD || conn->State == TCP_ST_SYN_SENT )
1003                 Threads_Yield();
1004
1005         if( conn->State != TCP_ST_OPEN ) {
1006                 VFS_MarkError(Node, 1);
1007                 LEAVE('i', -1);
1008                 return -1;
1009         }
1010
1011         do
1012         {
1013                  int    len = (rem < TCP_MAX_PACKET_SIZE) ? rem : TCP_MAX_PACKET_SIZE;
1014
1015                 #if 0
1016                 // Wait for space in the buffer
1017                 Semaphore_Signal( &Connection->SentBufferSpace, len );
1018
1019                 // Save data to buffer (and update the length read by the ammount written)
1020                 len = RingBuffer_Write( &Connection->SentBuffer, Buffer, len);
1021                 #endif
1022
1023                 // Send packet
1024                 TCP_INT_SendDataPacket(conn, len, Buffer);
1025
1026                 Buffer += len;
1027                 rem += len;
1028         } while( rem > 0 );
1029
1030         LEAVE('i', Length);
1031         return Length;
1032 }
1033
1034 /**
1035  * \brief Open a connection to another host using TCP
1036  * \param Conn  Connection structure
1037  */
1038 void TCP_StartConnection(tTCPConnection *Conn)
1039 {
1040         tTCPHeader      hdr = {0};
1041
1042         Conn->State = TCP_ST_SYN_SENT;
1043
1044         hdr.SourcePort = htons(Conn->LocalPort);
1045         hdr.DestPort = htons(Conn->RemotePort);
1046         Conn->NextSequenceSend = rand();
1047         hdr.SequenceNumber = htonl(Conn->NextSequenceSend);
1048         hdr.DataOffset = (sizeof(tTCPHeader)/4) << 4;
1049         hdr.Flags = TCP_FLAG_SYN;
1050         hdr.WindowSize = htons(TCP_WINDOW_SIZE);        // Max
1051         hdr.Checksum = 0;       // TODO
1052
1053         TCP_SendPacket( Conn, sizeof(tTCPHeader), &hdr );
1054
1055         Conn->NextSequenceSend ++;
1056         Conn->State = TCP_ST_SYN_SENT;
1057         return ;
1058 }
1059
1060 /**
1061  * \brief Control a client socket
1062  */
1063 int TCP_Client_IOCtl(tVFS_Node *Node, int ID, void *Data)
1064 {
1065         tTCPConnection  *conn = Node->ImplPtr;
1066
1067         ENTER("pNode iID pData", Node, ID, Data);
1068
1069         switch(ID)
1070         {
1071         case 4: // Get/Set local port
1072                 if(!Data)
1073                         LEAVE_RET('i', conn->LocalPort);
1074                 if(conn->State != TCP_ST_CLOSED)
1075                         LEAVE_RET('i', -1);
1076                 if(!CheckMem(Data, sizeof(Uint16)))
1077                         LEAVE_RET('i', -1);
1078
1079                 if(Threads_GetUID() != 0 && *(Uint16*)Data < 1024)
1080                         LEAVE_RET('i', -1);
1081
1082                 conn->LocalPort = *(Uint16*)Data;
1083                 LEAVE_RET('i', conn->LocalPort);
1084
1085         case 5: // Get/Set remote port
1086                 if(!Data)       LEAVE_RET('i', conn->RemotePort);
1087                 if(conn->State != TCP_ST_CLOSED)        LEAVE_RET('i', -1);
1088                 if(!CheckMem(Data, sizeof(Uint16)))     LEAVE_RET('i', -1);
1089                 conn->RemotePort = *(Uint16*)Data;
1090                 LEAVE_RET('i', conn->RemotePort);
1091
1092         case 6: // Set Remote IP
1093                 if( conn->State != TCP_ST_CLOSED )
1094                         LEAVE_RET('i', -1);
1095                 if( conn->Interface->Type == 4 )
1096                 {
1097                         if(!CheckMem(Data, sizeof(tIPv4)))      LEAVE_RET('i', -1);
1098                         conn->RemoteIP.v4 = *(tIPv4*)Data;
1099                 }
1100                 else if( conn->Interface->Type == 6 )
1101                 {
1102                         if(!CheckMem(Data, sizeof(tIPv6)))      LEAVE_RET('i', -1);
1103                         conn->RemoteIP.v6 = *(tIPv6*)Data;
1104                 }
1105                 LEAVE_RET('i', 0);
1106
1107         case 7: // Connect
1108                 if(conn->LocalPort == 0xFFFF)
1109                         conn->LocalPort = TCP_GetUnusedPort();
1110                 if(conn->RemotePort == -1)
1111                         LEAVE_RET('i', 0);
1112
1113                 TCP_StartConnection(conn);
1114                 LEAVE_RET('i', 1);
1115
1116         // Get recieve buffer length
1117         case 8:
1118                 LEAVE_RET('i', conn->RecievedBuffer->Length);
1119         }
1120
1121         return 0;
1122 }
1123
1124 void TCP_Client_Close(tVFS_Node *Node)
1125 {
1126         tTCPConnection  *conn = Node->ImplPtr;
1127         tTCPHeader      packet;
1128
1129         ENTER("pNode", Node);
1130
1131         if( conn->State == TCP_ST_CLOSE_WAIT || conn->State == TCP_ST_OPEN )
1132         {
1133                 packet.SourcePort = htons(conn->LocalPort);
1134                 packet.DestPort = htons(conn->RemotePort);
1135                 packet.DataOffset = (sizeof(tTCPHeader)/4)*16;
1136                 packet.WindowSize = TCP_WINDOW_SIZE;
1137
1138                 packet.AcknowlegementNumber = 0;
1139                 packet.SequenceNumber = htonl(conn->NextSequenceSend);
1140                 packet.Flags = TCP_FLAG_FIN|TCP_FLAG_ACK;
1141
1142                 TCP_SendPacket( conn, sizeof(tTCPHeader), &packet );
1143         }
1144
1145         switch( conn->State )
1146         {
1147         case TCP_ST_CLOSE_WAIT:
1148                 conn->State = TCP_ST_CLOSED;
1149                 break;
1150         case TCP_ST_OPEN:
1151                 conn->State = TCP_ST_FIN_WAIT1;
1152                 while( conn->State == TCP_ST_FIN_WAIT1 )        Threads_Yield();
1153                 break;
1154         default:
1155                 Log_Warning("TCP", "Unhandled connection state in TCP_Client_Close");
1156                 break;
1157         }
1158
1159         free(conn);
1160
1161         LEAVE('-');
1162 }
1163
1164 /**
1165  * \brief Checks if a value is between two others (after taking into account wrapping)
1166  */
1167 int WrapBetween(Uint32 Lower, Uint32 Value, Uint32 Higher, Uint32 MaxValue)
1168 {
1169         if( MaxValue < 0xFFFFFFFF )
1170         {
1171                 Lower %= MaxValue + 1;
1172                 Value %= MaxValue + 1;
1173                 Higher %= MaxValue + 1;
1174         }
1175
1176         // Simple Case, no wrap ?
1177         //       Lower Value Higher
1178         // | ... + ... + ... + ... |
1179
1180         if( Lower < Higher ) {
1181                 return Lower < Value && Value < Higher;
1182         }
1183         // Higher has wrapped below lower
1184
1185         // Value > Lower ?
1186         //       Higher Lower Value
1187         // | ... +  ... + ... + ... |
1188         if( Value > Lower ) {
1189                 return 1;
1190         }
1191
1192         // Value < Higher ?
1193         //       Value Higher Lower
1194         // | ... + ... +  ... + ... |
1195         if( Value < Higher ) {
1196                 return 1;
1197         }
1198
1199         return 0;
1200 }