KernelLand/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 "ipv6.h"
   9 #include "tcp.h"
  10
  11 #define USE_SELECT      1
  12 #define HEXDUMP_INCOMING        0
  13 #define HEXDUMP_OUTGOING        0
  14 #define CACHE_FUTURE_PACKETS_IN_BYTES   1       // Use a ring buffer to cache out of order packets
  15
  16 #define TCP_MIN_DYNPORT 0xC000
  17 #define TCP_MAX_HALFOPEN        1024    // Should be enough
  18
  19 #define TCP_MAX_PACKET_SIZE     1024
  20 #define TCP_WINDOW_SIZE 0x2000
  21 #define TCP_RECIEVE_BUFFER_SIZE 0x4000
  22
  23 // === PROTOTYPES ===
  24 void    TCP_Initialise(void);
  25 void    TCP_StartConnection(tTCPConnection *Conn);
  26 void    TCP_SendPacket(tTCPConnection *Conn, tTCPHeader *Header, size_t DataLen, const void *Data);
  27 void    TCP_GetPacket(tInterface *Interface, void *Address, int Length, void *Buffer);
  28 void    TCP_INT_HandleConnectionPacket(tTCPConnection *Connection, tTCPHeader *Header, int Length);
  29 int     TCP_INT_AppendRecieved(tTCPConnection *Connection, const void *Data, size_t Length);
  30 void    TCP_INT_UpdateRecievedFromFuture(tTCPConnection *Connection);
  31 Uint16  TCP_GetUnusedPort();
  32  int    TCP_AllocatePort(Uint16 Port);
  33  int    TCP_DeallocatePort(Uint16 Port);
  34 // --- Server
  35 tVFS_Node       *TCP_Server_Init(tInterface *Interface);
  36 char    *TCP_Server_ReadDir(tVFS_Node *Node, int Pos);
  37 tVFS_Node       *TCP_Server_FindDir(tVFS_Node *Node, const char *Name);
  38  int    TCP_Server_IOCtl(tVFS_Node *Node, int ID, void *Data);
  39 void    TCP_Server_Close(tVFS_Node *Node);
  40 // --- Client
  41 tVFS_Node       *TCP_Client_Init(tInterface *Interface);
  42 size_t  TCP_Client_Read(tVFS_Node *Node, off_t Offset, size_t Length, void *Buffer);
  43 size_t  TCP_Client_Write(tVFS_Node *Node, off_t Offset, size_t Length, const void *Buffer);
  44  int    TCP_Client_IOCtl(tVFS_Node *Node, int ID, void *Data);
  45 void    TCP_Client_Close(tVFS_Node *Node);
  46 // --- Helpers
  47  int    WrapBetween(Uint32 Lower, Uint32 Value, Uint32 Higher, Uint32 MaxValue);
  48
  49 // === TEMPLATES ===
  50 tSocketFile     gTCP_ServerFile = {NULL, "tcps", TCP_Server_Init};
  51 tSocketFile     gTCP_ClientFile = {NULL, "tcpc", TCP_Client_Init};
  52 tVFS_NodeType   gTCP_ServerNodeType = {
  53         .TypeName = "TCP Server",
  54         .ReadDir = TCP_Server_ReadDir,
  55         .FindDir = TCP_Server_FindDir,
  56         .IOCtl   = TCP_Server_IOCtl,
  57         .Close   = TCP_Server_Close
  58         };
  59 tVFS_NodeType   gTCP_ClientNodeType = {
  60         .TypeName = "TCP Client/Connection",
  61         .Read  = TCP_Client_Read,
  62         .Write = TCP_Client_Write,
  63         .IOCtl = TCP_Client_IOCtl,
  64         .Close = TCP_Client_Close
  65         };
  66
  67 // === GLOBALS ===
  68  int    giTCP_NumHalfopen = 0;
  69 tShortSpinlock  glTCP_Listeners;
  70 tTCPListener    *gTCP_Listeners;
  71 tShortSpinlock  glTCP_OutbountCons;
  72 tTCPConnection  *gTCP_OutbountCons;
  73 Uint32  gaTCP_PortBitmap[0x800];
  74  int    giTCP_NextOutPort = TCP_MIN_DYNPORT;
  75
  76 // === CODE ===
  77 /**
  78  * \brief Initialise the TCP Layer
  79  *
  80  * Registers the client and server files and the GetPacket callback
  81  */
  82 void TCP_Initialise(void)
  83 {
  84         giTCP_NextOutPort += rand()%32;
  85         IPStack_AddFile(&gTCP_ServerFile);
  86         IPStack_AddFile(&gTCP_ClientFile);
  87         IPv4_RegisterCallback(IP4PROT_TCP, TCP_GetPacket);
  88         IPv6_RegisterCallback(IP4PROT_TCP, TCP_GetPacket);
  89 }
  90
  91 /**
  92  * \brief Sends a packet from the specified connection, calculating the checksums
  93  * \param Conn  Connection
  94  * \param Length        Length of data
  95  * \param Data  Packet data (cast as a TCP Header)
  96  */
  97 void TCP_SendPacket( tTCPConnection *Conn, tTCPHeader *Header, size_t Length, const void *Data )
  98 {
  99         tIPStackBuffer  *buffer;
 100         Uint16  checksum[3];
 101          int    packlen = sizeof(*Header) + Length;
 102
 103         buffer = IPStack_Buffer_CreateBuffer(2 + IPV4_BUFFERS);
 104         if( Data && Length )
 105                 IPStack_Buffer_AppendSubBuffer(buffer, Length, 0, Data, NULL, NULL);
 106         IPStack_Buffer_AppendSubBuffer(buffer, sizeof(*Header), 0, Header, NULL, NULL);
 107
 108         Log_Debug("TCP", "Sending %i+%i to %s:%i", sizeof(*Header), Length,
 109                 IPStack_PrintAddress(Conn->Interface->Type, &Conn->RemoteIP),
 110                 Conn->RemotePort
 111                 );
 112
 113         Header->Checksum = 0;
 114         checksum[1] = htons( ~IPv4_Checksum(Header, sizeof(tTCPHeader)) );
 115         checksum[2] = htons( ~IPv4_Checksum(Data, Length) );
 116
 117         // TODO: Fragment packet
 118
 119         switch( Conn->Interface->Type )
 120         {
 121         case 4:
 122                 // Get IPv4 pseudo-header checksum
 123                 {
 124                         Uint32  buf[3];
 125                         buf[0] = ((tIPv4*)Conn->Interface->Address)->L;
 126                         buf[1] = Conn->RemoteIP.v4.L;
 127                         buf[2] = (htons(packlen)<<16) | (6<<8) | 0;
 128                         checksum[0] = htons( ~IPv4_Checksum(buf, sizeof(buf)) );        // Partial checksum
 129                 }
 130                 // - Combine checksums
 131                 Header->Checksum = htons( IPv4_Checksum(checksum, sizeof(checksum)) );
 132                 IPv4_SendPacket(Conn->Interface, Conn->RemoteIP.v4, IP4PROT_TCP, 0, buffer);
 133                 break;
 134
 135         case 6:
 136                 // Append IPv6 Pseudo Header
 137                 {
 138                         Uint32  buf[4+4+1+1];
 139                         memcpy(buf, Conn->Interface->Address, 16);
 140                         memcpy(&buf[4], &Conn->RemoteIP, 16);
 141                         buf[8] = htonl(packlen);
 142                         buf[9] = htonl(6);
 143                         checksum[0] = htons( ~IPv4_Checksum(buf, sizeof(buf)) );        // Partial checksum
 144                 }
 145                 Header->Checksum = htons( IPv4_Checksum(checksum, sizeof(checksum)) );  // Combine the two
 146                 IPv6_SendPacket(Conn->Interface, Conn->RemoteIP.v6, IP4PROT_TCP, Length, Data);
 147                 break;
 148         }
 149 }
 150
 151 /**
 152  * \brief Handles a packet from the IP Layer
 153  * \param Interface     Interface the packet arrived from
 154  * \param Address       Pointer to the addres structure
 155  * \param Length        Size of packet in bytes
 156  * \param Buffer        Packet data
 157  */
 158 void TCP_GetPacket(tInterface *Interface, void *Address, int Length, void *Buffer)
 159 {
 160         tTCPHeader      *hdr = Buffer;
 161         tTCPListener    *srv;
 162         tTCPConnection  *conn;
 163
 164         Log_Log("TCP", "TCP_GetPacket: <Local>:%i from [%s]:%i, Flags= %s%s%s%s%s%s%s%s",
 165                 ntohs(hdr->DestPort),
 166                 IPStack_PrintAddress(Interface->Type, Address),
 167                 ntohs(hdr->SourcePort),
 168                 (hdr->Flags & TCP_FLAG_CWR) ? "CWR " : "",
 169                 (hdr->Flags & TCP_FLAG_ECE) ? "ECE " : "",
 170                 (hdr->Flags & TCP_FLAG_URG) ? "URG " : "",
 171                 (hdr->Flags & TCP_FLAG_ACK) ? "ACK " : "",
 172                 (hdr->Flags & TCP_FLAG_PSH) ? "PSH " : "",
 173                 (hdr->Flags & TCP_FLAG_RST) ? "RST " : "",
 174                 (hdr->Flags & TCP_FLAG_SYN) ? "SYN " : "",
 175                 (hdr->Flags & TCP_FLAG_FIN) ? "FIN " : ""
 176                 );
 177
 178         if( Length > (hdr->DataOffset >> 4)*4 )
 179         {
 180                 Log_Log("TCP", "TCP_GetPacket: SequenceNumber = 0x%x", ntohl(hdr->SequenceNumber));
 181 #if HEXDUMP_INCOMING
 182                 Debug_HexDump(
 183                         "TCP_GetPacket: Packet Data = ",
 184                         (Uint8*)hdr + (hdr->DataOffset >> 4)*4,
 185                         Length - (hdr->DataOffset >> 4)*4
 186                         );
 187 #endif
 188         }
 189
 190         // Check Servers
 191         for( srv = gTCP_Listeners; srv; srv = srv->Next )
 192         {
 193                 // Check if the server is active
 194                 if(srv->Port == 0)      continue;
 195                 // Check the interface
 196                 if(srv->Interface && srv->Interface != Interface)       continue;
 197                 // Check the destination port
 198                 if(srv->Port != htons(hdr->DestPort))   continue;
 199
 200                 Log_Log("TCP", "TCP_GetPacket: Matches server %p", srv);
 201                 // Is this in an established connection?
 202                 for( conn = srv->Connections; conn; conn = conn->Next )
 203                 {
 204                         // Check that it is coming in on the same interface
 205                         if(conn->Interface != Interface)        continue;
 206
 207                         // Check Source Port
 208                         Log_Log("TCP", "TCP_GetPacket: conn->RemotePort(%i) == hdr->SourcePort(%i)",
 209                                 conn->RemotePort, ntohs(hdr->SourcePort));
 210                         if(conn->RemotePort != ntohs(hdr->SourcePort))  continue;
 211
 212                         // Check Source IP
 213                         Log_Debug("TCP", "TCP_GetPacket: conn->RemoteIP(%s)",
 214                                 IPStack_PrintAddress(conn->Interface->Type, &conn->RemoteIP));
 215                         Log_Debug("TCP", "                == Address(%s)",
 216                                 IPStack_PrintAddress(conn->Interface->Type, Address));
 217                         if( IPStack_CompareAddress(conn->Interface->Type, &conn->RemoteIP, Address, -1) == 0 )
 218                                 continue ;
 219
 220                         Log_Log("TCP", "TCP_GetPacket: Matches connection %p", conn);
 221                         // We have a response!
 222                         TCP_INT_HandleConnectionPacket(conn, hdr, Length);
 223
 224                         return;
 225                 }
 226
 227                 Log_Log("TCP", "TCP_GetPacket: Opening Connection");
 228                 // Open a new connection (well, check that it's a SYN)
 229                 if(hdr->Flags != TCP_FLAG_SYN) {
 230                         Log_Log("TCP", "TCP_GetPacket: Packet is not a SYN");
 231                         return ;
 232                 }
 233
 234                 // TODO: Check for halfopen max
 235
 236                 conn = calloc(1, sizeof(tTCPConnection));
 237                 conn->State = TCP_ST_SYN_RCVD;
 238                 conn->LocalPort = srv->Port;
 239                 conn->RemotePort = ntohs(hdr->SourcePort);
 240                 conn->Interface = Interface;
 241
 242                 switch(Interface->Type)
 243                 {
 244                 case 4: conn->RemoteIP.v4 = *(tIPv4*)Address;   break;
 245                 case 6: conn->RemoteIP.v6 = *(tIPv6*)Address;   break;
 246                 }
 247
 248                 conn->RecievedBuffer = RingBuffer_Create( TCP_RECIEVE_BUFFER_SIZE );
 249
 250                 conn->NextSequenceRcv = ntohl( hdr->SequenceNumber ) + 1;
 251                 conn->NextSequenceSend = rand();
 252
 253                 // Create node
 254                 conn->Node.NumACLs = 1;
 255                 conn->Node.ACLs = &gVFS_ACL_EveryoneRW;
 256                 conn->Node.ImplPtr = conn;
 257                 conn->Node.ImplInt = srv->NextID ++;
 258                 conn->Node.Type = &gTCP_ClientNodeType; // TODO: Special type for the server end?
 259
 260                 // Hmm... Theoretically, this lock will never have to wait,
 261                 // as the interface is locked to the watching thread, and this
 262                 // runs in the watching thread. But, it's a good idea to have
 263                 // it, just in case
 264                 // Oh, wait, there is a case where a wildcard can be used
 265                 // (srv->Interface == NULL) so having the lock is a good idea
 266                 SHORTLOCK(&srv->lConnections);
 267                 if( !srv->Connections )
 268                         srv->Connections = conn;
 269                 else
 270                         srv->ConnectionsTail->Next = conn;
 271                 srv->ConnectionsTail = conn;
 272                 if(!srv->NewConnections)
 273                         srv->NewConnections = conn;
 274                 VFS_MarkAvaliable( &srv->Node, 1 );
 275                 SHORTREL(&srv->lConnections);
 276
 277                 // Send the SYN ACK
 278                 hdr->Flags |= TCP_FLAG_ACK;
 279                 hdr->AcknowlegementNumber = htonl(conn->NextSequenceRcv);
 280                 hdr->SequenceNumber = htonl(conn->NextSequenceSend);
 281                 hdr->DestPort = hdr->SourcePort;
 282                 hdr->SourcePort = htons(srv->Port);
 283                 hdr->DataOffset = (sizeof(tTCPHeader)/4) << 4;
 284                 TCP_SendPacket( conn, hdr, 0, NULL );
 285                 conn->NextSequenceSend ++;
 286                 return ;
 287         }
 288
 289         // Check Open Connections
 290         {
 291                 for( conn = gTCP_OutbountCons; conn; conn = conn->Next )
 292                 {
 293                         // Check that it is coming in on the same interface
 294                         if(conn->Interface != Interface)        continue;
 295
 296                         // Check Source Port
 297                         if(conn->RemotePort != ntohs(hdr->SourcePort))  continue;
 298
 299                         // Check Source IP
 300                         if(conn->Interface->Type == 6 && !IP6_EQU(conn->RemoteIP.v6, *(tIPv6*)Address))
 301                                 continue;
 302                         if(conn->Interface->Type == 4 && !IP4_EQU(conn->RemoteIP.v4, *(tIPv4*)Address))
 303                                 continue;
 304
 305                         TCP_INT_HandleConnectionPacket(conn, hdr, Length);
 306                         return ;
 307                 }
 308         }
 309
 310         Log_Log("TCP", "TCP_GetPacket: No Match");
 311 }
 312
 313 /**
 314  * \brief Handles a packet sent to a specific connection
 315  * \param Connection    TCP Connection pointer
 316  * \param Header        TCP Packet pointer
 317  * \param Length        Length of the packet
 318  */
 319 void TCP_INT_HandleConnectionPacket(tTCPConnection *Connection, tTCPHeader *Header, int Length)
 320 {
 321          int    dataLen;
 322         Uint32  sequence_num;
 323
 324         // Silently drop once finished
 325         // TODO: Check if this needs to be here
 326         if( Connection->State == TCP_ST_FINISHED ) {
 327                 Log_Log("TCP", "Packet ignored - connection finnished");
 328                 return ;
 329         }
 330
 331         // Syncronise sequence values
 332         if(Header->Flags & TCP_FLAG_SYN) {
 333                 // TODO: What if the packet also has data?
 334                 Connection->NextSequenceRcv = ntohl(Header->SequenceNumber);
 335         }
 336
 337         // Ackowledge a sent packet
 338         if(Header->Flags & TCP_FLAG_ACK) {
 339                 // TODO: Process an ACKed Packet
 340                 Log_Log("TCP", "Conn %p, Sent packet 0x%x ACKed", Connection, Header->AcknowlegementNumber);
 341         }
 342
 343         // Get length of data
 344         dataLen = Length - (Header->DataOffset>>4)*4;
 345         Log_Log("TCP", "HandleConnectionPacket - dataLen = %i", dataLen);
 346
 347         //
 348         // State Machine
 349         //
 350         switch( Connection->State )
 351         {
 352         // Pre-init connection?
 353         case TCP_ST_CLOSED:
 354                 Log_Log("TCP", "Packets to a closed connection?!");
 355                 break;
 356
 357         // --- Init States ---
 358         // SYN sent, expecting SYN-ACK Connection Opening
 359         case TCP_ST_SYN_SENT:
 360                 if( Header->Flags & TCP_FLAG_SYN )
 361                 {
 362                         Connection->NextSequenceRcv ++;
 363                         Header->DestPort = Header->SourcePort;
 364                         Header->SourcePort = htons(Connection->LocalPort);
 365                         Header->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 366                         Header->SequenceNumber = htonl(Connection->NextSequenceSend);
 367                         Header->WindowSize = htons(TCP_WINDOW_SIZE);
 368                         Header->Flags = TCP_FLAG_ACK;
 369                         Header->DataOffset = (sizeof(tTCPHeader)/4) << 4;
 370                         TCP_SendPacket( Connection, Header, 0, NULL );
 371
 372                         if( Header->Flags & TCP_FLAG_ACK )
 373                         {
 374                                 Log_Log("TCP", "ACKing SYN-ACK");
 375                                 Connection->State = TCP_ST_OPEN;
 376                         }
 377                         else
 378                         {
 379                                 Log_Log("TCP", "ACKing SYN");
 380                                 Connection->State = TCP_ST_SYN_RCVD;
 381                         }
 382                 }
 383                 break;
 384
 385         // SYN-ACK sent, expecting ACK
 386         case TCP_ST_SYN_RCVD:
 387                 if( Header->Flags & TCP_FLAG_ACK )
 388                 {
 389                         // TODO: Handle max half-open limit
 390                         Connection->State = TCP_ST_OPEN;
 391                         Log_Log("TCP", "Connection fully opened");
 392                 }
 393                 break;
 394
 395         // --- Established State ---
 396         case TCP_ST_OPEN:
 397                 // - Handle State changes
 398                 //
 399                 if( Header->Flags & TCP_FLAG_FIN ) {
 400                         Log_Log("TCP", "Conn %p closed, recieved FIN", Connection);
 401                         VFS_MarkError(&Connection->Node, 1);
 402                         Connection->State = TCP_ST_CLOSE_WAIT;
 403 //                      Header->Flags &= ~TCP_FLAG_FIN;
 404                         // CLOSE WAIT requires the client to close (or does it?)
 405                         #if 0
 406
 407                         #endif
 408                 }
 409
 410                 // Check for an empty packet
 411                 if(dataLen == 0) {
 412                         if( Header->Flags == TCP_FLAG_ACK )
 413                         {
 414                                 Log_Log("TCP", "ACK only packet");
 415                                 return ;
 416                         }
 417                         Connection->NextSequenceRcv ++; // TODO: Is this right? (empty packet counts as one byte)
 418                         Log_Log("TCP", "Empty Packet, inc and ACK the current sequence number");
 419                         Header->DestPort = Header->SourcePort;
 420                         Header->SourcePort = htons(Connection->LocalPort);
 421                         Header->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 422                         Header->SequenceNumber = htonl(Connection->NextSequenceSend);
 423                         Header->Flags |= TCP_FLAG_ACK;
 424                         TCP_SendPacket( Connection, Header, 0, NULL );
 425                         return ;
 426                 }
 427
 428                 // NOTES:
 429                 // Flags
 430                 //    PSH - Has Data?
 431                 // /NOTES
 432
 433                 sequence_num = ntohl(Header->SequenceNumber);
 434
 435                 Log_Log("TCP", "0x%08x <= 0x%08x < 0x%08x",
 436                         Connection->NextSequenceRcv,
 437                         ntohl(Header->SequenceNumber),
 438                         Connection->NextSequenceRcv + TCP_WINDOW_SIZE
 439                         );
 440
 441                 // Is this packet the next expected packet?
 442                 if( sequence_num == Connection->NextSequenceRcv )
 443                 {
 444                          int    rv;
 445                         // Ooh, Goodie! Add it to the recieved list
 446                         rv = TCP_INT_AppendRecieved(Connection,
 447                                 (Uint8*)Header + (Header->DataOffset>>4)*4,
 448                                 dataLen
 449                                 );
 450                         if(rv != 0) {
 451                                 break;
 452                         }
 453                         Log_Log("TCP", "0x%08x += %i", Connection->NextSequenceRcv, dataLen);
 454                         Connection->NextSequenceRcv += dataLen;
 455
 456                         // TODO: This should be moved out of the watcher thread,
 457                         // so that a single lost packet on one connection doesn't cause
 458                         // all connections on the interface to lag.
 459                         // - Meh, no real issue, as the cache shouldn't be that large
 460                         TCP_INT_UpdateRecievedFromFuture(Connection);
 461
 462                         // ACK Packet
 463                         Header->DestPort = Header->SourcePort;
 464                         Header->SourcePort = htons(Connection->LocalPort);
 465                         Header->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 466                         Header->SequenceNumber = htonl(Connection->NextSequenceSend);
 467                         Header->WindowSize = htons(TCP_WINDOW_SIZE);
 468                         Header->Flags &= TCP_FLAG_SYN;  // Eliminate all flags save for SYN
 469                         Header->Flags |= TCP_FLAG_ACK;  // Add ACK
 470                         Log_Log("TCP", "Sending ACK for 0x%08x", Connection->NextSequenceRcv);
 471                         TCP_SendPacket( Connection, Header, 0, NULL );
 472                         //Connection->NextSequenceSend ++;
 473                 }
 474                 // Check if the packet is in window
 475                 else if( WrapBetween(Connection->NextSequenceRcv, sequence_num,
 476                                 Connection->NextSequenceRcv+TCP_WINDOW_SIZE, 0xFFFFFFFF) )
 477                 {
 478                         Uint8   *dataptr = (Uint8*)Header + (Header->DataOffset>>4)*4;
 479                         #if CACHE_FUTURE_PACKETS_IN_BYTES
 480                         Uint32  index;
 481                          int    i;
 482
 483                         index = sequence_num % TCP_WINDOW_SIZE;
 484                         for( i = 0; i < dataLen; i ++ )
 485                         {
 486                                 Connection->FuturePacketValidBytes[index/8] |= 1 << (index%8);
 487                                 Connection->FuturePacketData[index] = dataptr[i];
 488                                 // Do a wrap increment
 489                                 index ++;
 490                                 if(index == TCP_WINDOW_SIZE)    index = 0;
 491                         }
 492                         #else
 493                         tTCPStoredPacket        *pkt, *tmp, *prev = NULL;
 494
 495                         // Allocate and fill cached packet
 496                         pkt = malloc( sizeof(tTCPStoredPacket) + dataLen );
 497                         pkt->Next = NULL;
 498                         pkt->Sequence = ntohl(Header->SequenceNumber);
 499                         pkt->Length = dataLen;
 500                         memcpy(pkt->Data, dataptr, dataLen);
 501
 502                         Log_Log("TCP", "We missed a packet, caching",
 503                                 pkt->Sequence, Connection->NextSequenceRcv);
 504
 505                         // No? Well, let's cache it and look at it later
 506                         SHORTLOCK( &Connection->lFuturePackets );
 507                         for(tmp = Connection->FuturePackets;
 508                                 tmp;
 509                                 prev = tmp, tmp = tmp->Next)
 510                         {
 511                                 if(tmp->Sequence >= pkt->Sequence)      break;
 512                         }
 513
 514                         // Add if before first, or sequences don't match
 515                         if( !tmp || tmp->Sequence != pkt->Sequence )
 516                         {
 517                                 if(prev)
 518                                         prev->Next = pkt;
 519                                 else
 520                                         Connection->FuturePackets = pkt;
 521                                 pkt->Next = tmp;
 522                         }
 523                         // Replace if larger
 524                         else if(pkt->Length > tmp->Length)
 525                         {
 526                                 if(prev)
 527                                         prev->Next = pkt;
 528                                 pkt->Next = tmp->Next;
 529                                 free(tmp);
 530                         }
 531                         else
 532                         {
 533                                 free(pkt);      // TODO: Find some way to remove this
 534                         }
 535                         SHORTREL( &Connection->lFuturePackets );
 536                         #endif
 537                 }
 538                 // Badly out of sequence packet
 539                 else
 540                 {
 541                         Log_Log("TCP", "Fully out of sequence packet (0x%08x not between 0x%08x and 0x%08x), dropped",
 542                                 sequence_num, Connection->NextSequenceRcv, Connection->NextSequenceRcv+TCP_WINDOW_SIZE);
 543                         // TODO: Spec says we should send an empty ACK with the current state
 544                 }
 545                 break;
 546
 547         // --- Remote close states
 548         case TCP_ST_CLOSE_WAIT:
 549
 550                 // Ignore everything, CLOSE_WAIT is terminated by the client
 551                 Log_Debug("TCP", "CLOSE WAIT - Ignoring packets");
 552
 553                 break;
 554
 555         // LAST-ACK - Waiting for the ACK of FIN (from CLOSE WAIT)
 556         case TCP_ST_LAST_ACK:
 557                 if( Header->Flags & TCP_FLAG_ACK )
 558                 {
 559                         Connection->State = TCP_ST_FINISHED;    // Connection completed
 560                         Log_Log("TCP", "LAST-ACK to CLOSED - Connection remote closed");
 561                         // TODO: Destrory the TCB
 562                 }
 563                 break;
 564
 565         // --- Local close States
 566         case TCP_ST_FIN_WAIT1:
 567                 if( Header->Flags & TCP_FLAG_FIN )
 568                 {
 569                         Connection->State = TCP_ST_CLOSING;
 570                         Log_Debug("TCP", "Conn %p closed, sent FIN and recieved FIN", Connection);
 571                         VFS_MarkError(&Connection->Node, 1);
 572
 573                         // ACK Packet
 574                         Header->DestPort = Header->SourcePort;
 575                         Header->SourcePort = htons(Connection->LocalPort);
 576                         Header->AcknowlegementNumber = Header->SequenceNumber;
 577                         Header->SequenceNumber = htonl(Connection->NextSequenceSend);
 578                         Header->WindowSize = htons(TCP_WINDOW_SIZE);
 579                         Header->Flags = TCP_FLAG_ACK;
 580                         TCP_SendPacket( Connection, Header, 0, NULL );
 581                         break ;
 582                 }
 583
 584                 // TODO: Make sure that the packet is actually ACKing the FIN
 585                 if( Header->Flags & TCP_FLAG_ACK )
 586                 {
 587                         Connection->State = TCP_ST_FIN_WAIT2;
 588                         Log_Debug("TCP", "Conn %p closed, sent FIN ACKed", Connection);
 589                         VFS_MarkError(&Connection->Node, 1);
 590                         return ;
 591                 }
 592                 break;
 593
 594         case TCP_ST_FIN_WAIT2:
 595                 if( Header->Flags & TCP_FLAG_FIN )
 596                 {
 597                         Connection->State = TCP_ST_TIME_WAIT;
 598                         Log_Debug("TCP", "FIN sent and recieved, ACKing and going into TIME WAIT %p FINWAIT-2 -> TIME WAIT", Connection);
 599                         // Send ACK
 600                         Header->DestPort = Header->SourcePort;
 601                         Header->SourcePort = htons(Connection->LocalPort);
 602                         Header->AcknowlegementNumber = Header->SequenceNumber;
 603                         Header->SequenceNumber = htonl(Connection->NextSequenceSend);
 604                         Header->WindowSize = htons(TCP_WINDOW_SIZE);
 605                         Header->Flags = TCP_FLAG_ACK;
 606                         TCP_SendPacket( Connection, Header, 0, NULL );
 607                 }
 608                 break;
 609
 610         case TCP_ST_CLOSING:
 611                 // TODO: Make sure that the packet is actually ACKing the FIN
 612                 if( Header->Flags & TCP_FLAG_ACK )
 613                 {
 614                         Connection->State = TCP_ST_TIME_WAIT;
 615                         Log_Debug("TCP", "Conn %p CLOSING -> TIME WAIT", Connection);
 616                         VFS_MarkError(&Connection->Node, 1);
 617                         return ;
 618                 }
 619                 break;
 620
 621         // --- Closed (or near closed) states) ---
 622         case TCP_ST_TIME_WAIT:
 623                 Log_Log("TCP", "Packets on Time-Wait, ignored");
 624                 break;
 625
 626         case TCP_ST_FINISHED:
 627                 Log_Log("TCP", "Packets when CLOSED, ignoring");
 628                 break;
 629
 630         //default:
 631         //      Log_Warning("TCP", "Unhandled TCP state %i", Connection->State);
 632         //      break;
 633         }
 634
 635 }
 636
 637 /**
 638  * \brief Appends a packet to the recieved list
 639  * \param Connection    Connection structure
 640  * \param Data  Packet contents
 641  * \param Length        Length of \a Data
 642  */
 643 int TCP_INT_AppendRecieved(tTCPConnection *Connection, const void *Data, size_t Length)
 644 {
 645         Mutex_Acquire( &Connection->lRecievedPackets );
 646
 647         if(Connection->RecievedBuffer->Length + Length > Connection->RecievedBuffer->Space )
 648         {
 649                 VFS_MarkAvaliable(&Connection->Node, 1);
 650                 Log_Error("TCP", "Buffer filled, packet dropped (:%i) - %i + %i > %i",
 651                         Connection->LocalPort, Connection->RecievedBuffer->Length, Length,
 652                         Connection->RecievedBuffer->Space
 653                         );
 654                 Mutex_Release( &Connection->lRecievedPackets );
 655                 return 1;
 656         }
 657
 658         RingBuffer_Write( Connection->RecievedBuffer, Data, Length );
 659
 660         VFS_MarkAvaliable(&Connection->Node, 1);
 661
 662         Mutex_Release( &Connection->lRecievedPackets );
 663         return 0;
 664 }
 665
 666 /**
 667  * \brief Updates the connections recieved list from the future list
 668  * \param Connection    Connection structure
 669  *
 670  * Updates the recieved packets list with packets from the future (out
 671  * of order) packets list that are now able to be added in direct
 672  * sequence.
 673  */
 674 void TCP_INT_UpdateRecievedFromFuture(tTCPConnection *Connection)
 675 {
 676         #if CACHE_FUTURE_PACKETS_IN_BYTES
 677          int    i, length = 0;
 678         Uint32  index;
 679
 680         // Calculate length of contiguous bytes
 681         length = Connection->HighestSequenceRcvd - Connection->NextSequenceRcv;
 682         index = Connection->NextSequenceRcv % TCP_WINDOW_SIZE;
 683         for( i = 0; i < length; i ++ )
 684         {
 685                 if( Connection->FuturePacketValidBytes[i / 8] == 0xFF ) {
 686                         i += 7; index += 7;
 687                         continue;
 688                 }
 689                 else if( !(Connection->FuturePacketValidBytes[i / 8] & (1 << (i%8))) )
 690                         break;
 691
 692                 index ++;
 693                 if(index > TCP_WINDOW_SIZE)
 694                         index -= TCP_WINDOW_SIZE;
 695         }
 696         length = i;
 697
 698         index = Connection->NextSequenceRcv % TCP_WINDOW_SIZE;
 699
 700         // Write data to to the ring buffer
 701         if( TCP_WINDOW_SIZE - index > length )
 702         {
 703                 // Simple case
 704                 RingBuffer_Write( Connection->RecievedBuffer, Connection->FuturePacketData + index, length );
 705         }
 706         else
 707         {
 708                  int    endLen = TCP_WINDOW_SIZE - index;
 709                 // 2-part case
 710                 RingBuffer_Write( Connection->RecievedBuffer, Connection->FuturePacketData + index, endLen );
 711                 RingBuffer_Write( Connection->RecievedBuffer, Connection->FuturePacketData, endLen - length );
 712         }
 713
 714         // Mark (now saved) bytes as invalid
 715         // - Align index
 716         while(index % 8 && length)
 717         {
 718                 Connection->FuturePacketData[index] = 0;
 719                 Connection->FuturePacketData[index/8] &= ~(1 << (index%8));
 720                 index ++;
 721                 if(index > TCP_WINDOW_SIZE)
 722                         index -= TCP_WINDOW_SIZE;
 723                 length --;
 724         }
 725         while( length > 7 )
 726         {
 727                 Connection->FuturePacketData[index] = 0;
 728                 Connection->FuturePacketValidBytes[index/8] = 0;
 729                 length -= 8;
 730                 index += 8;
 731                 if(index > TCP_WINDOW_SIZE)
 732                         index -= TCP_WINDOW_SIZE;
 733         }
 734         while(length)
 735         {
 736                 Connection->FuturePacketData[index] = 0;
 737                 Connection->FuturePacketData[index/8] &= ~(1 << (index%8));
 738                 index ++;
 739                 if(index > TCP_WINDOW_SIZE)
 740                         index -= TCP_WINDOW_SIZE;
 741                 length --;
 742         }
 743
 744         #else
 745         tTCPStoredPacket        *pkt;
 746         for(;;)
 747         {
 748                 SHORTLOCK( &Connection->lFuturePackets );
 749
 750                 // Clear out duplicates from cache
 751                 // - If a packet has just been recieved, and it is expected, then
 752                 //   (since NextSequenceRcv = rcvd->Sequence + rcvd->Length) all
 753                 //   packets in cache that are smaller than the next expected
 754                 //   are now defunct.
 755                 pkt = Connection->FuturePackets;
 756                 while(pkt && pkt->Sequence < Connection->NextSequenceRcv)
 757                 {
 758                         tTCPStoredPacket        *next = pkt->Next;
 759                         free(pkt);
 760                         pkt = next;
 761                 }
 762
 763                 // If there's no packets left in cache, stop looking
 764                 if(!pkt || pkt->Sequence > Connection->NextSequenceRcv) {
 765                         SHORTREL( &Connection->lFuturePackets );
 766                         return;
 767                 }
 768
 769                 // Delete packet from future list
 770                 Connection->FuturePackets = pkt->Next;
 771
 772                 // Release list
 773                 SHORTREL( &Connection->lFuturePackets );
 774
 775                 // Looks like we found one
 776                 TCP_INT_AppendRecieved(Connection, pkt);
 777                 Connection->NextSequenceRcv += pkt->Length;
 778                 free(pkt);
 779         }
 780         #endif
 781 }
 782
 783 /**
 784  * \fn Uint16 TCP_GetUnusedPort()
 785  * \brief Gets an unused port and allocates it
 786  */
 787 Uint16 TCP_GetUnusedPort()
 788 {
 789         Uint16  ret;
 790
 791         // Get Next outbound port
 792         ret = giTCP_NextOutPort++;
 793         while( gaTCP_PortBitmap[ret/32] & (1UL << (ret%32)) )
 794         {
 795                 ret ++;
 796                 giTCP_NextOutPort++;
 797                 if(giTCP_NextOutPort == 0x10000) {
 798                         ret = giTCP_NextOutPort = TCP_MIN_DYNPORT;
 799                 }
 800         }
 801
 802         // Mark the new port as used
 803         gaTCP_PortBitmap[ret/32] |= 1 << (ret%32);
 804
 805         return ret;
 806 }
 807
 808 /**
 809  * \fn int TCP_AllocatePort(Uint16 Port)
 810  * \brief Marks a port as used
 811  */
 812 int TCP_AllocatePort(Uint16 Port)
 813 {
 814         // Check if the port has already been allocated
 815         if( gaTCP_PortBitmap[Port/32] & (1 << (Port%32)) )
 816                 return 0;
 817
 818         // Allocate
 819         gaTCP_PortBitmap[Port/32] |= 1 << (Port%32);
 820
 821         return 1;
 822 }
 823
 824 /**
 825  * \fn int TCP_DeallocatePort(Uint16 Port)
 826  * \brief Marks a port as unused
 827  */
 828 int TCP_DeallocatePort(Uint16 Port)
 829 {
 830         // Check if the port has already been allocated
 831         if( !(gaTCP_PortBitmap[Port/32] & (1 << (Port%32))) )
 832                 return 0;
 833
 834         // Allocate
 835         gaTCP_PortBitmap[Port/32] &= ~(1 << (Port%32));
 836
 837         return 1;
 838 }
 839
 840 // --- Server
 841 tVFS_Node *TCP_Server_Init(tInterface *Interface)
 842 {
 843         tTCPListener    *srv;
 844
 845         srv = calloc( 1, sizeof(tTCPListener) );
 846
 847         if( srv == NULL ) {
 848                 Log_Warning("TCP", "malloc failed for listener (%i) bytes", sizeof(tTCPListener));
 849                 return NULL;
 850         }
 851
 852         srv->Interface = Interface;
 853         srv->Port = 0;
 854         srv->NextID = 0;
 855         srv->Connections = NULL;
 856         srv->ConnectionsTail = NULL;
 857         srv->NewConnections = NULL;
 858         srv->Next = NULL;
 859         srv->Node.Flags = VFS_FFLAG_DIRECTORY;
 860         srv->Node.Size = -1;
 861         srv->Node.ImplPtr = srv;
 862         srv->Node.NumACLs = 1;
 863         srv->Node.ACLs = &gVFS_ACL_EveryoneRW;
 864         srv->Node.Type = &gTCP_ServerNodeType;
 865
 866         SHORTLOCK(&glTCP_Listeners);
 867         srv->Next = gTCP_Listeners;
 868         gTCP_Listeners = srv;
 869         SHORTREL(&glTCP_Listeners);
 870
 871         return &srv->Node;
 872 }
 873
 874 /**
 875  * \brief Wait for a new connection and return the connection ID
 876  * \note Blocks until a new connection is made
 877  * \param Node  Server node
 878  * \param Pos   Position (ignored)
 879  */
 880 char *TCP_Server_ReadDir(tVFS_Node *Node, int Pos)
 881 {
 882         tTCPListener    *srv = Node->ImplPtr;
 883         tTCPConnection  *conn;
 884         char    *ret;
 885
 886         ENTER("pNode iPos", Node, Pos);
 887
 888         Log_Log("TCP", "Thread %i waiting for a connection", Threads_GetTID());
 889         for(;;)
 890         {
 891                 SHORTLOCK( &srv->lConnections );
 892                 if( srv->NewConnections != NULL )       break;
 893                 SHORTREL( &srv->lConnections );
 894                 Threads_Yield();        // TODO: Sleep until poked
 895         }
 896
 897
 898         // Increment the new list (the current connection is still on the
 899         // normal list)
 900         conn = srv->NewConnections;
 901         srv->NewConnections = conn->Next;
 902
 903         if( srv->NewConnections == NULL )
 904                 VFS_MarkAvaliable( Node, 0 );
 905
 906         SHORTREL( &srv->lConnections );
 907
 908         LOG("conn = %p", conn);
 909         LOG("srv->Connections = %p", srv->Connections);
 910         LOG("srv->NewConnections = %p", srv->NewConnections);
 911         LOG("srv->ConnectionsTail = %p", srv->ConnectionsTail);
 912
 913         ret = malloc(9);
 914         itoa(ret, conn->Node.ImplInt, 16, 8, '0');
 915         Log_Log("TCP", "Thread %i got '%s'", Threads_GetTID(), ret);
 916         LEAVE('s', ret);
 917         return ret;
 918 }
 919
 920 /**
 921  * \brief Gets a client connection node
 922  * \param Node  Server node
 923  * \param Name  Hexadecimal ID of the node
 924  */
 925 tVFS_Node *TCP_Server_FindDir(tVFS_Node *Node, const char *Name)
 926 {
 927         tTCPConnection  *conn;
 928         tTCPListener    *srv = Node->ImplPtr;
 929         char    tmp[9];
 930          int    id = atoi(Name);
 931
 932         ENTER("pNode sName", Node, Name);
 933
 934         // Check for a non-empty name
 935         if( Name[0] )
 936         {
 937                 // Sanity Check
 938                 itoa(tmp, id, 16, 8, '0');
 939                 if(strcmp(tmp, Name) != 0) {
 940                         LOG("'%s' != '%s' (%08x)", Name, tmp, id);
 941                         LEAVE('n');
 942                         return NULL;
 943                 }
 944
 945                 Log_Debug("TCP", "srv->Connections = %p", srv->Connections);
 946                 Log_Debug("TCP", "srv->NewConnections = %p", srv->NewConnections);
 947                 Log_Debug("TCP", "srv->ConnectionsTail = %p", srv->ConnectionsTail);
 948
 949                 // Search
 950                 SHORTLOCK( &srv->lConnections );
 951                 for(conn = srv->Connections;
 952                         conn;
 953                         conn = conn->Next)
 954                 {
 955                         LOG("conn->Node.ImplInt = %i", conn->Node.ImplInt);
 956                         if(conn->Node.ImplInt == id)    break;
 957                 }
 958                 SHORTREL( &srv->lConnections );
 959
 960                 // If not found, ret NULL
 961                 if(!conn) {
 962                         LOG("Connection %i not found", id);
 963                         LEAVE('n');
 964                         return NULL;
 965                 }
 966         }
 967         // Empty Name - Check for a new connection and if it's there, open it
 968         else
 969         {
 970                 SHORTLOCK( &srv->lConnections );
 971                 conn = srv->NewConnections;
 972                 if( conn != NULL )
 973                         srv->NewConnections = conn->Next;
 974                 VFS_MarkAvaliable( Node, srv->NewConnections != NULL );
 975                 SHORTREL( &srv->lConnections );
 976                 if( !conn ) {
 977                         LOG("No new connections");
 978                         LEAVE('n');
 979                         return NULL;
 980                 }
 981         }
 982
 983         // Return node
 984         LEAVE('p', &conn->Node);
 985         return &conn->Node;
 986 }
 987
 988 /**
 989  * \brief Handle IOCtl calls
 990  */
 991 int TCP_Server_IOCtl(tVFS_Node *Node, int ID, void *Data)
 992 {
 993         tTCPListener    *srv = Node->ImplPtr;
 994
 995         switch(ID)
 996         {
 997         case 4: // Get/Set Port
 998                 if(!Data)       // Get Port
 999                         return srv->Port;
1000
1001                 if(srv->Port)   // Wait, you can't CHANGE the port
1002                         return -1;
1003
1004                 if(!CheckMem(Data, sizeof(Uint16)))     // Sanity check
1005                         return -1;
1006
1007                 // Permissions check
1008                 if(Threads_GetUID() != 0
1009                 && *(Uint16*)Data != 0
1010                 && *(Uint16*)Data < 1024)
1011                         return -1;
1012
1013                 // TODO: Check if a port is in use
1014
1015                 // Set Port
1016                 srv->Port = *(Uint16*)Data;
1017                 if(srv->Port == 0)      // Allocate a random port
1018                         srv->Port = TCP_GetUnusedPort();
1019                 else    // Else, mark this as used
1020                         TCP_AllocatePort(srv->Port);
1021
1022                 Log_Log("TCP", "Server %p listening on port %i", srv, srv->Port);
1023
1024                 return srv->Port;
1025         }
1026         return 0;
1027 }
1028
1029 void TCP_Server_Close(tVFS_Node *Node)
1030 {
1031         free(Node->ImplPtr);
1032 }
1033
1034 // --- Client
1035 /**
1036  * \brief Create a client node
1037  */
1038 tVFS_Node *TCP_Client_Init(tInterface *Interface)
1039 {
1040         tTCPConnection  *conn = calloc( sizeof(tTCPConnection) + TCP_WINDOW_SIZE + TCP_WINDOW_SIZE/8, 1 );
1041
1042         conn->State = TCP_ST_CLOSED;
1043         conn->Interface = Interface;
1044         conn->LocalPort = -1;
1045         conn->RemotePort = -1;
1046
1047         conn->Node.ImplPtr = conn;
1048         conn->Node.NumACLs = 1;
1049         conn->Node.ACLs = &gVFS_ACL_EveryoneRW;
1050         conn->Node.Type = &gTCP_ClientNodeType;
1051
1052         conn->RecievedBuffer = RingBuffer_Create( TCP_RECIEVE_BUFFER_SIZE );
1053         #if 0
1054         conn->SentBuffer = RingBuffer_Create( TCP_SEND_BUFFER_SIZE );
1055         Semaphore_Init(conn->SentBufferSpace, 0, TCP_SEND_BUFFER_SIZE, "TCP SentBuffer", conn->Name);
1056         #endif
1057
1058         #if CACHE_FUTURE_PACKETS_IN_BYTES
1059         // Future recieved data (ahead of the expected sequence number)
1060         conn->FuturePacketData = (Uint8*)conn + sizeof(tTCPConnection);
1061         conn->FuturePacketValidBytes = conn->FuturePacketData + TCP_WINDOW_SIZE;
1062         #endif
1063
1064         SHORTLOCK(&glTCP_OutbountCons);
1065         conn->Next = gTCP_OutbountCons;
1066         gTCP_OutbountCons = conn;
1067         SHORTREL(&glTCP_OutbountCons);
1068
1069         return &conn->Node;
1070 }
1071
1072 /**
1073  * \brief Wait for a packet and return it
1074  * \note If \a Length is smaller than the size of the packet, the rest
1075  *       of the packet's data will be discarded.
1076  */
1077 size_t TCP_Client_Read(tVFS_Node *Node, off_t Offset, size_t Length, void *Buffer)
1078 {
1079         tTCPConnection  *conn = Node->ImplPtr;
1080         size_t  len;
1081
1082         ENTER("pNode XOffset XLength pBuffer", Node, Offset, Length, Buffer);
1083         LOG("conn = %p {State:%i}", conn, conn->State);
1084
1085         // Check if connection is estabilishing
1086         // - TODO: Sleep instead (maybe using VFS_SelectNode to wait for the
1087         //   data to be availiable
1088         while( conn->State == TCP_ST_SYN_RCVD || conn->State == TCP_ST_SYN_SENT )
1089                 Threads_Yield();
1090
1091         // If the conneciton is not open, then clean out the recieved buffer
1092         if( conn->State != TCP_ST_OPEN )
1093         {
1094                 Mutex_Acquire( &conn->lRecievedPackets );
1095                 len = RingBuffer_Read( Buffer, conn->RecievedBuffer, Length );
1096                 Mutex_Release( &conn->lRecievedPackets );
1097
1098                 if( len == 0 ) {
1099                         VFS_MarkAvaliable(Node, 0);
1100                         LEAVE('i', -1);
1101                         return -1;
1102                 }
1103
1104                 LEAVE('i', len);
1105                 return len;
1106         }
1107
1108         // Wait
1109         VFS_SelectNode(Node, VFS_SELECT_READ|VFS_SELECT_ERROR, NULL, "TCP_Client_Read");
1110
1111         // Lock list and read as much as possible (up to `Length`)
1112         Mutex_Acquire( &conn->lRecievedPackets );
1113         len = RingBuffer_Read( Buffer, conn->RecievedBuffer, Length );
1114
1115         if( len == 0 || conn->RecievedBuffer->Length == 0 ) {
1116                 LOG("Marking as none avaliable (len = %i)", len);
1117                 VFS_MarkAvaliable(Node, 0);
1118         }
1119
1120         // Release the lock (we don't need it any more)
1121         Mutex_Release( &conn->lRecievedPackets );
1122
1123         LEAVE('i', len);
1124         return len;
1125 }
1126
1127 /**
1128  * \brief Send a data packet on a connection
1129  */
1130 void TCP_INT_SendDataPacket(tTCPConnection *Connection, size_t Length, const void *Data)
1131 {
1132         char    buf[sizeof(tTCPHeader)+Length];
1133         tTCPHeader      *packet = (void*)buf;
1134
1135         packet->SourcePort = htons(Connection->LocalPort);
1136         packet->DestPort = htons(Connection->RemotePort);
1137         packet->DataOffset = (sizeof(tTCPHeader)/4)*16;
1138         packet->WindowSize = htons(TCP_WINDOW_SIZE);
1139
1140         packet->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
1141         packet->SequenceNumber = htonl(Connection->NextSequenceSend);
1142         packet->Flags = TCP_FLAG_PSH|TCP_FLAG_ACK;      // Hey, ACK if you can!
1143
1144         memcpy(packet->Options, Data, Length);
1145
1146         Log_Debug("TCP", "Send sequence 0x%08x", Connection->NextSequenceSend);
1147 #if HEXDUMP_OUTGOING
1148         Debug_HexDump("TCP_INT_SendDataPacket: Data = ", Data, Length);
1149 #endif
1150
1151         TCP_SendPacket( Connection, packet, Length, Data );
1152
1153         Connection->NextSequenceSend += Length;
1154 }
1155
1156 /**
1157  * \brief Send some bytes on a connection
1158  */
1159 size_t TCP_Client_Write(tVFS_Node *Node, off_t Offset, size_t Length, const void *Buffer)
1160 {
1161         tTCPConnection  *conn = Node->ImplPtr;
1162         size_t  rem = Length;
1163
1164         ENTER("pNode XOffset XLength pBuffer", Node, Offset, Length, Buffer);
1165
1166 //      #if DEBUG
1167 //      Debug_HexDump("TCP_Client_Write: Buffer = ",
1168 //              Buffer, Length);
1169 //      #endif
1170
1171         // Check if connection is open
1172         while( conn->State == TCP_ST_SYN_RCVD || conn->State == TCP_ST_SYN_SENT )
1173                 Threads_Yield();
1174
1175         if( conn->State != TCP_ST_OPEN ) {
1176                 VFS_MarkError(Node, 1);
1177                 LEAVE('i', -1);
1178                 return -1;
1179         }
1180
1181         do
1182         {
1183                  int    len = (rem < TCP_MAX_PACKET_SIZE) ? rem : TCP_MAX_PACKET_SIZE;
1184
1185                 #if 0
1186                 // Wait for space in the buffer
1187                 Semaphore_Signal( &Connection->SentBufferSpace, len );
1188
1189                 // Save data to buffer (and update the length read by the ammount written)
1190                 len = RingBuffer_Write( &Connection->SentBuffer, Buffer, len);
1191                 #endif
1192
1193                 // Send packet
1194                 TCP_INT_SendDataPacket(conn, len, Buffer);
1195
1196                 Buffer += len;
1197                 rem -= len;
1198         } while( rem > 0 );
1199
1200         LEAVE('i', Length);
1201         return Length;
1202 }
1203
1204 /**
1205  * \brief Open a connection to another host using TCP
1206  * \param Conn  Connection structure
1207  */
1208 void TCP_StartConnection(tTCPConnection *Conn)
1209 {
1210         tTCPHeader      hdr = {0};
1211
1212         Conn->State = TCP_ST_SYN_SENT;
1213
1214         hdr.SourcePort = htons(Conn->LocalPort);
1215         hdr.DestPort = htons(Conn->RemotePort);
1216         Conn->NextSequenceSend = rand();
1217         hdr.SequenceNumber = htonl(Conn->NextSequenceSend);
1218         hdr.DataOffset = (sizeof(tTCPHeader)/4) << 4;
1219         hdr.Flags = TCP_FLAG_SYN;
1220         hdr.WindowSize = htons(TCP_WINDOW_SIZE);        // Max
1221         hdr.Checksum = 0;       // TODO
1222
1223         TCP_SendPacket( Conn, &hdr, 0, NULL );
1224
1225         Conn->NextSequenceSend ++;
1226         Conn->State = TCP_ST_SYN_SENT;
1227
1228         return ;
1229 }
1230
1231 /**
1232  * \brief Control a client socket
1233  */
1234 int TCP_Client_IOCtl(tVFS_Node *Node, int ID, void *Data)
1235 {
1236         tTCPConnection  *conn = Node->ImplPtr;
1237
1238         ENTER("pNode iID pData", Node, ID, Data);
1239
1240         switch(ID)
1241         {
1242         case 4: // Get/Set local port
1243                 if(!Data)
1244                         LEAVE_RET('i', conn->LocalPort);
1245                 if(conn->State != TCP_ST_CLOSED)
1246                         LEAVE_RET('i', -1);
1247                 if(!CheckMem(Data, sizeof(Uint16)))
1248                         LEAVE_RET('i', -1);
1249
1250                 if(Threads_GetUID() != 0 && *(Uint16*)Data < 1024)
1251                         LEAVE_RET('i', -1);
1252
1253                 conn->LocalPort = *(Uint16*)Data;
1254                 LEAVE_RET('i', conn->LocalPort);
1255
1256         case 5: // Get/Set remote port
1257                 if(!Data)       LEAVE_RET('i', conn->RemotePort);
1258                 if(conn->State != TCP_ST_CLOSED)        LEAVE_RET('i', -1);
1259                 if(!CheckMem(Data, sizeof(Uint16)))     LEAVE_RET('i', -1);
1260                 conn->RemotePort = *(Uint16*)Data;
1261                 LEAVE_RET('i', conn->RemotePort);
1262
1263         case 6: // Set Remote IP
1264                 if( conn->State != TCP_ST_CLOSED )
1265                         LEAVE_RET('i', -1);
1266                 if( conn->Interface->Type == 4 )
1267                 {
1268                         if(!CheckMem(Data, sizeof(tIPv4)))      LEAVE_RET('i', -1);
1269                         conn->RemoteIP.v4 = *(tIPv4*)Data;
1270                 }
1271                 else if( conn->Interface->Type == 6 )
1272                 {
1273                         if(!CheckMem(Data, sizeof(tIPv6)))      LEAVE_RET('i', -1);
1274                         conn->RemoteIP.v6 = *(tIPv6*)Data;
1275                 }
1276                 LEAVE_RET('i', 0);
1277
1278         case 7: // Connect
1279                 if(conn->LocalPort == 0xFFFF)
1280                         conn->LocalPort = TCP_GetUnusedPort();
1281                 if(conn->RemotePort == -1)
1282                         LEAVE_RET('i', 0);
1283
1284                 {
1285                         tTime   timeout_end = now() + conn->Interface->TimeoutDelay;
1286
1287                         TCP_StartConnection(conn);
1288                         // TODO: Wait for connection to open
1289                         while( conn->State == TCP_ST_SYN_SENT && timeout_end > now() ) {
1290                                 Threads_Yield();
1291                         }
1292                         if( conn->State == TCP_ST_SYN_SENT )
1293                                 LEAVE_RET('i', 0);
1294                 }
1295
1296                 LEAVE_RET('i', 1);
1297
1298         // Get recieve buffer length
1299         case 8:
1300                 LEAVE_RET('i', conn->RecievedBuffer->Length);
1301         }
1302
1303         return 0;
1304 }
1305
1306 void TCP_Client_Close(tVFS_Node *Node)
1307 {
1308         tTCPConnection  *conn = Node->ImplPtr;
1309         tTCPHeader      packet;
1310
1311         ENTER("pNode", Node);
1312
1313         if( conn->State == TCP_ST_CLOSE_WAIT || conn->State == TCP_ST_OPEN )
1314         {
1315                 packet.SourcePort = htons(conn->LocalPort);
1316                 packet.DestPort = htons(conn->RemotePort);
1317                 packet.DataOffset = (sizeof(tTCPHeader)/4)*16;
1318                 packet.WindowSize = TCP_WINDOW_SIZE;
1319
1320                 packet.AcknowlegementNumber = 0;
1321                 packet.SequenceNumber = htonl(conn->NextSequenceSend);
1322                 packet.Flags = TCP_FLAG_FIN;
1323
1324                 TCP_SendPacket( conn, &packet, 0, NULL );
1325         }
1326
1327         switch( conn->State )
1328         {
1329         case TCP_ST_CLOSE_WAIT:
1330                 conn->State = TCP_ST_LAST_ACK;
1331                 break;
1332         case TCP_ST_OPEN:
1333                 conn->State = TCP_ST_FIN_WAIT1;
1334                 while( conn->State == TCP_ST_FIN_WAIT1 )        Threads_Yield();
1335                 break;
1336         default:
1337                 Log_Warning("TCP", "Unhandled connection state in TCP_Client_Close");
1338                 break;
1339         }
1340
1341         free(conn);
1342
1343         LEAVE('-');
1344 }
1345
1346 /**
1347  * \brief Checks if a value is between two others (after taking into account wrapping)
1348  */
1349 int WrapBetween(Uint32 Lower, Uint32 Value, Uint32 Higher, Uint32 MaxValue)
1350 {
1351         if( MaxValue < 0xFFFFFFFF )
1352         {
1353                 Lower %= MaxValue + 1;
1354                 Value %= MaxValue + 1;
1355                 Higher %= MaxValue + 1;
1356         }
1357
1358         // Simple Case, no wrap ?
1359         //       Lower Value Higher
1360         // | ... + ... + ... + ... |
1361
1362         if( Lower < Higher ) {
1363                 return Lower < Value && Value < Higher;
1364         }
1365         // Higher has wrapped below lower
1366
1367         // Value > Lower ?
1368         //       Higher Lower Value
1369         // | ... +  ... + ... + ... |
1370         if( Value > Lower ) {
1371                 return 1;
1372         }
1373
1374         // Value < Higher ?
1375         //       Value Higher Lower
1376         // | ... + ... +  ... + ... |
1377         if( Value < Higher ) {
1378                 return 1;
1379         }
1380
1381         return 0;
1382 }