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 TCP_MIN_DYNPORT 0xC000
  11 #define TCP_MAX_HALFOPEN        1024    // Should be enough
  12
  13 #define TCP_MAX_PACKET_SIZE     1024
  14 #define TCP_WINDOW_SIZE 0x2000
  15 #define TCP_RECIEVE_BUFFER_SIZE 0x4000
  16
  17 // === PROTOTYPES ===
  18 void    TCP_Initialise();
  19 void    TCP_StartConnection(tTCPConnection *Conn);
  20 void    TCP_SendPacket(tTCPConnection *Conn, size_t Length, tTCPHeader *Data);
  21 void    TCP_GetPacket(tInterface *Interface, void *Address, int Length, void *Buffer);
  22 void    TCP_INT_HandleConnectionPacket(tTCPConnection *Connection, tTCPHeader *Header, int Length);
  23 void    TCP_INT_AppendRecieved(tTCPConnection *Connection, tTCPStoredPacket *Ptk);
  24 void    TCP_INT_UpdateRecievedFromFuture(tTCPConnection *Connection);
  25 Uint16  TCP_GetUnusedPort();
  26  int    TCP_AllocatePort(Uint16 Port);
  27  int    TCP_DeallocatePort(Uint16 Port);
  28 // --- Server
  29 tVFS_Node       *TCP_Server_Init(tInterface *Interface);
  30 char    *TCP_Server_ReadDir(tVFS_Node *Node, int Pos);
  31 tVFS_Node       *TCP_Server_FindDir(tVFS_Node *Node, char *Name);
  32  int    TCP_Server_IOCtl(tVFS_Node *Node, int ID, void *Data);
  33 void    TCP_Server_Close(tVFS_Node *Node);
  34 // --- Client
  35 tVFS_Node       *TCP_Client_Init(tInterface *Interface);
  36 Uint64  TCP_Client_Read(tVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer);
  37 Uint64  TCP_Client_Write(tVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer);
  38  int    TCP_Client_IOCtl(tVFS_Node *Node, int ID, void *Data);
  39 void    TCP_Client_Close(tVFS_Node *Node);
  40
  41 // === TEMPLATES ===
  42 tSocketFile     gTCP_ServerFile = {NULL, "tcps", TCP_Server_Init};
  43 tSocketFile     gTCP_ClientFile = {NULL, "tcpc", TCP_Client_Init};
  44
  45 // === GLOBALS ===
  46  int    giTCP_NumHalfopen = 0;
  47 tSpinlock       glTCP_Listeners;
  48 tTCPListener    *gTCP_Listeners;
  49 tSpinlock       glTCP_OutbountCons;
  50 tTCPConnection  *gTCP_OutbountCons;
  51 Uint32  gaTCP_PortBitmap[0x800];
  52  int    giTCP_NextOutPort = TCP_MIN_DYNPORT;
  53
  54 // === CODE ===
  55 /**
  56  * \brief Initialise the TCP Layer
  57  *
  58  * Registers the client and server files and the GetPacket callback
  59  */
  60 void TCP_Initialise()
  61 {
  62         IPStack_AddFile(&gTCP_ServerFile);
  63         IPStack_AddFile(&gTCP_ClientFile);
  64         IPv4_RegisterCallback(IP4PROT_TCP, TCP_GetPacket);
  65 }
  66
  67 /**
  68  * \brief Open a connection to another host using TCP
  69  * \param Conn  Connection structure
  70  */
  71 void TCP_StartConnection(tTCPConnection *Conn)
  72 {
  73         tTCPHeader      hdr;
  74
  75         hdr.SourcePort = Conn->LocalPort;
  76         hdr.DestPort = Conn->RemotePort;
  77         Conn->NextSequenceSend = rand();
  78         hdr.SequenceNumber = Conn->NextSequenceSend;
  79         hdr.DataOffset = (sizeof(tTCPHeader)/4) << 4;
  80         hdr.Flags = TCP_FLAG_SYN;
  81         hdr.WindowSize = 0xFFFF;        // Max
  82         hdr.Checksum = 0;       // TODO
  83         hdr.UrgentPointer = 0;
  84
  85         TCP_SendPacket( Conn, sizeof(tTCPHeader), &hdr );
  86         return ;
  87 }
  88
  89 /**
  90  * \brief Sends a packet from the specified connection, calculating the checksums
  91  * \param Conn  Connection
  92  * \param Length        Length of data
  93  * \param Data  Packet data (cast as a TCP Header)
  94  */
  95 void TCP_SendPacket( tTCPConnection *Conn, size_t Length, tTCPHeader *Data )
  96 {
  97         size_t  buflen;
  98         Uint32  *buf;
  99         switch( Conn->Interface->Type )
 100         {
 101         case 4: // Append IPv4 Pseudo Header
 102                 buflen = 4 + 4 + 4 + ((Length+1)&~1);
 103                 buf = malloc( buflen );
 104                 buf[0] = Conn->Interface->IP4.Address.L;
 105                 buf[1] = Conn->RemoteIP.v4.L;
 106                 buf[2] = (htons(Length)<<16) | (6<<8) | 0;
 107                 Data->Checksum = 0;
 108                 memcpy( &buf[3], Data, Length );
 109                 Data->Checksum = IPv4_Checksum( buf, buflen );
 110                 free(buf);
 111                 IPv4_SendPacket(Conn->Interface, Conn->RemoteIP.v4, IP4PROT_TCP, 0, Length, Data);
 112                 break;
 113         }
 114 }
 115
 116 /**
 117  * \brief Handles a packet from the IP Layer
 118  * \param Interface     Interface the packet arrived from
 119  * \param Address       Pointer to the addres structure
 120  * \param Length        Size of packet in bytes
 121  * \param Buffer        Packet data
 122  */
 123 void TCP_GetPacket(tInterface *Interface, void *Address, int Length, void *Buffer)
 124 {
 125         tTCPHeader      *hdr = Buffer;
 126         tTCPListener    *srv;
 127         tTCPConnection  *conn;
 128
 129         Log_Log("TCP", "SourcePort = %i, DestPort = %i",
 130                 ntohs(hdr->SourcePort), ntohs(hdr->DestPort));
 131         Log_Log("TCP", "SequenceNumber = 0x%x", ntohl(hdr->SequenceNumber));
 132         Log_Log("TCP", "AcknowlegementNumber = 0x%x", ntohl(hdr->AcknowlegementNumber));
 133 /*
 134         Log_Log("TCP", "DataOffset = %i", hdr->DataOffset >> 4);
 135         Log_Log("TCP", "Flags = {");
 136         Log_Log("TCP", "  CWR = %B, ECE = %B",
 137                 !!(hdr->Flags & TCP_FLAG_CWR), !!(hdr->Flags & TCP_FLAG_ECE));
 138         Log_Log("TCP", "  URG = %B, ACK = %B",
 139                 !!(hdr->Flags & TCP_FLAG_URG), !!(hdr->Flags & TCP_FLAG_ACK));
 140         Log_Log("TCP", "  PSH = %B, RST = %B",
 141                 !!(hdr->Flags & TCP_FLAG_PSH), !!(hdr->Flags & TCP_FLAG_RST));
 142         Log_Log("TCP", "  SYN = %B, FIN = %B",
 143                 !!(hdr->Flags & TCP_FLAG_SYN), !!(hdr->Flags & TCP_FLAG_FIN));
 144         Log_Log("TCP", "}");
 145         Log_Log("TCP", "WindowSize = %i", htons(hdr->WindowSize));
 146         Log_Log("TCP", "Checksum = 0x%x", htons(hdr->Checksum));
 147         Log_Log("TCP", "UrgentPointer = 0x%x", htons(hdr->UrgentPointer));
 148 */
 149
 150         if( Length > (hdr->DataOffset >> 4)*4 )
 151         {
 152                 Debug_HexDump(
 153                         "[TCP  ] Packet Data = ",
 154                         (Uint8*)hdr + (hdr->DataOffset >> 4)*4,
 155                         Length - (hdr->DataOffset >> 4)*4
 156                         );
 157         }
 158
 159         // Check Servers
 160         {
 161                 for( srv = gTCP_Listeners; srv; srv = srv->Next )
 162                 {
 163                         // Check if the server is active
 164                         if(srv->Port == 0)      continue;
 165                         // Check the interface
 166                         if(srv->Interface && srv->Interface != Interface)       continue;
 167                         // Check the destination port
 168                         if(srv->Port != htons(hdr->DestPort))   continue;
 169
 170                         Log_Log("TCP", "Matches server %p", srv);
 171                         // Is this in an established connection?
 172                         for( conn = srv->Connections; conn; conn = conn->Next )
 173                         {
 174                                 Log_Log("TCP", "conn->Interface(%p) == Interface(%p)",
 175                                         conn->Interface, Interface);
 176                                 // Check that it is coming in on the same interface
 177                                 if(conn->Interface != Interface)        continue;
 178
 179                                 // Check Source Port
 180                                 Log_Log("TCP", "conn->RemotePort(%i) == hdr->SourcePort(%i)",
 181                                         conn->RemotePort, ntohs(hdr->SourcePort));
 182                                 if(conn->RemotePort != ntohs(hdr->SourcePort))  continue;
 183
 184                                 // Check Source IP
 185                                 if(conn->Interface->Type == 6 && !IP6_EQU(conn->RemoteIP.v6, *(tIPv6*)Address))
 186                                         continue;
 187                                 if(conn->Interface->Type == 4 && !IP4_EQU(conn->RemoteIP.v4, *(tIPv4*)Address))
 188                                         continue;
 189
 190                                 Log_Log("TCP", "Matches connection %p", conn);
 191                                 // We have a response!
 192                                 TCP_INT_HandleConnectionPacket(conn, hdr, Length);
 193
 194                                 return;
 195                         }
 196
 197                         Log_Log("TCP", "Opening Connection");
 198                         // Open a new connection (well, check that it's a SYN)
 199                         if(hdr->Flags != TCP_FLAG_SYN) {
 200                                 Log_Log("TCP", "Packet is not a SYN");
 201                                 return ;
 202                         }
 203
 204                         // TODO: Check for halfopen max
 205
 206                         conn = calloc(1, sizeof(tTCPConnection));
 207                         conn->State = TCP_ST_HALFOPEN;
 208                         conn->LocalPort = srv->Port;
 209                         conn->RemotePort = ntohs(hdr->SourcePort);
 210                         conn->Interface = Interface;
 211
 212                         switch(Interface->Type)
 213                         {
 214                         case 4: conn->RemoteIP.v4 = *(tIPv4*)Address;   break;
 215                         case 6: conn->RemoteIP.v6 = *(tIPv6*)Address;   break;
 216                         }
 217
 218                         conn->RecievedBuffer = RingBuffer_Create( TCP_RECIEVE_BUFFER_SIZE );
 219
 220                         conn->NextSequenceRcv = ntohl( hdr->SequenceNumber ) + 1;
 221                         conn->NextSequenceSend = rand();
 222
 223                         // Create node
 224                         conn->Node.NumACLs = 1;
 225                         conn->Node.ACLs = &gVFS_ACL_EveryoneRW;
 226                         conn->Node.ImplPtr = conn;
 227                         conn->Node.ImplInt = srv->NextID ++;
 228                         conn->Node.Read = TCP_Client_Read;
 229                         conn->Node.Write = TCP_Client_Write;
 230                         //conn->Node.Close = TCP_SrvConn_Close;
 231
 232                         // Hmm... Theoretically, this lock will never have to wait,
 233                         // as the interface is locked to the watching thread, and this
 234                         // runs in the watching thread. But, it's a good idea to have
 235                         // it, just in case
 236                         // Oh, wait, there is a case where a wildcard can be used
 237                         // (srv->Interface == NULL) so having the lock is a good idea
 238                         LOCK(&srv->lConnections);
 239                         if( !srv->Connections )
 240                                 srv->Connections = conn;
 241                         else
 242                                 srv->ConnectionsTail->Next = conn;
 243                         srv->ConnectionsTail = conn;
 244                         if(!srv->NewConnections)
 245                                 srv->NewConnections = conn;
 246                         RELEASE(&srv->lConnections);
 247
 248                         // Send the SYN ACK
 249                         hdr->Flags |= TCP_FLAG_ACK;
 250                         hdr->AcknowlegementNumber = htonl(conn->NextSequenceRcv);
 251                         hdr->SequenceNumber = htonl(conn->NextSequenceSend);
 252                         hdr->DestPort = hdr->SourcePort;
 253                         hdr->SourcePort = htons(srv->Port);
 254                         hdr->DataOffset = (sizeof(tTCPHeader)/4) << 4;
 255                         TCP_SendPacket( conn, sizeof(tTCPHeader), hdr );
 256                         conn->NextSequenceSend ++;
 257                         return ;
 258                 }
 259         }
 260
 261
 262         // Check Open Connections
 263         {
 264                 for( conn = gTCP_OutbountCons; conn; conn = conn->Next )
 265                 {
 266                         // Check that it is coming in on the same interface
 267                         if(conn->Interface != Interface)        continue;
 268
 269                         // Check Source Port
 270                         if(conn->RemotePort != ntohs(hdr->SourcePort))  continue;
 271
 272                         // Check Source IP
 273                         if(conn->Interface->Type == 6 && !IP6_EQU(conn->RemoteIP.v6, *(tIPv6*)Address))
 274                                 continue;
 275                         if(conn->Interface->Type == 4 && !IP4_EQU(conn->RemoteIP.v4, *(tIPv4*)Address))
 276                                 continue;
 277
 278                         TCP_INT_HandleConnectionPacket(conn, hdr, Length);
 279                         return ;
 280                 }
 281         }
 282
 283         Log_Log("TCP", "No Match");
 284 }
 285
 286 /**
 287  * \brief Handles a packet sent to a specific connection
 288  * \param Connection    TCP Connection pointer
 289  * \param Header        TCP Packet pointer
 290  * \param Length        Length of the packet
 291  */
 292 void TCP_INT_HandleConnectionPacket(tTCPConnection *Connection, tTCPHeader *Header, int Length)
 293 {
 294         tTCPStoredPacket        *pkt;
 295          int    dataLen;
 296
 297         Connection->State = TCP_ST_OPEN;
 298         if(Header->Flags & TCP_FLAG_SYN) {
 299                 Connection->NextSequenceRcv = ntohl(Header->SequenceNumber) + 1;
 300         }
 301
 302         // Get length of data
 303         dataLen = Length - (Header->DataOffset>>4)*4;
 304         Log_Log("TCP", "HandleConnectionPacket - dataLen = %i", dataLen);
 305
 306         if(Header->Flags & TCP_FLAG_ACK) {
 307                 // TODO: Process an ACKed Packet
 308                 Log_Log("TCP", "Conn %p, Packet 0x%x ACKed", Connection, Header->AcknowlegementNumber);
 309         }
 310
 311         if(dataLen == 0) {
 312                 Log_Log("TCP", "Empty Packet");
 313                 return ;
 314         }
 315
 316         // NOTES:
 317         // Flags
 318         //    PSH - Has Data?
 319         // /NOTES
 320
 321         // Allocate and fill cached packet
 322         pkt = malloc( dataLen + sizeof(tTCPStoredPacket) );
 323         pkt->Next = NULL;
 324         pkt->Sequence = ntohl(Header->SequenceNumber);
 325         pkt->Length = dataLen;
 326         memcpy(pkt->Data, (Uint8*)Header + (Header->DataOffset>>4)*4, dataLen);
 327
 328         // Is this packet the next expected packet?
 329         // TODO: Fix this to check if the packet is in the window.
 330         if( pkt->Sequence != Connection->NextSequenceRcv )
 331         {
 332                 tTCPStoredPacket        *tmp, *prev = NULL;
 333
 334                 Log_Log("TCP", "Out of sequence packet (0x%08x != 0x%08x)",
 335                         pkt->Sequence, Connection->NextSequenceRcv);
 336
 337                 // No? Well, let's cache it and look at it later
 338                 LOCK( &Connection->lFuturePackets );
 339                 for(tmp = Connection->FuturePackets;
 340                         tmp;
 341                         prev = tmp, tmp = tmp->Next)
 342                 {
 343                         if(tmp->Sequence > pkt->Sequence)       break;
 344                 }
 345                 if(prev)
 346                         prev->Next = pkt;
 347                 else
 348                         Connection->FuturePackets = pkt;
 349                 pkt->Next = tmp;
 350                 RELEASE( &Connection->lFuturePackets );
 351         }
 352         else
 353         {
 354                 // Ooh, Goodie! Add it to the recieved list
 355                 TCP_INT_AppendRecieved(Connection, pkt);
 356                 free(pkt);
 357                 Log_Log("TCP", "0x%08x += %i", Connection->NextSequenceRcv, dataLen);
 358                 Connection->NextSequenceRcv += dataLen + 1;
 359
 360                 // TODO: This should be moved out of the watcher thread,
 361                 // so that a single lost packet on one connection doesn't cause
 362                 // all connections on the interface to lag.
 363                 TCP_INT_UpdateRecievedFromFuture(Connection);
 364
 365                 // ACK Packet
 366                 Header->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 367                 Header->SequenceNumber = htonl(Connection->NextSequenceSend);
 368                 Header->WindowSize = htons(TCP_WINDOW_SIZE);
 369                 Header->Flags &= TCP_FLAG_SYN;  // Eliminate all flags save for SYN
 370                 Header->Flags |= TCP_FLAG_ACK;  // Add ACK
 371                 Log_Log("TCP", "Sending ACK for 0x%08x", Connection->NextSequenceRcv);
 372                 TCP_SendPacket( Connection, sizeof(tTCPHeader), Header );
 373         }
 374 }
 375
 376 /**
 377  * \brief Appends a packet to the recieved list
 378  * \param Connection    Connection structure
 379  * \param Pkt   Packet structure on heap
 380  */
 381 void TCP_INT_AppendRecieved(tTCPConnection *Connection, tTCPStoredPacket *Pkt)
 382 {
 383         LOCK( &Connection->lRecievedPackets );
 384         if(Connection->RecievedBuffer->Length + Pkt->Length > Connection->RecievedBuffer->Space )
 385         {
 386                 Log_Error("TCP", "Buffer filled, packet dropped (%s)",
 387                 //      TCP_INT_DumpConnection(Connection)
 388                         ""
 389                         );
 390                 return ;
 391         }
 392
 393         RingBuffer_Write( Connection->RecievedBuffer, Pkt->Data, Pkt->Length );
 394
 395         RELEASE( &Connection->lRecievedPackets );
 396 }
 397
 398 /**
 399  * \brief Updates the connections recieved list from the future list
 400  * \param Connection    Connection structure
 401  *
 402  * Updates the recieved packets list with packets from the future (out
 403  * of order) packets list that are now able to be added in direct
 404  * sequence.
 405  */
 406 void TCP_INT_UpdateRecievedFromFuture(tTCPConnection *Connection)
 407 {
 408         tTCPStoredPacket        *pkt, *prev;
 409         for(;;)
 410         {
 411                 prev = NULL;
 412                 // Look for the next expected packet in the cache.
 413                 LOCK( &Connection->lFuturePackets );
 414                 for(pkt = Connection->FuturePackets;
 415                         pkt && pkt->Sequence < Connection->NextSequenceRcv;
 416                         prev = pkt, pkt = pkt->Next);
 417
 418                 // If we can't find the expected next packet, stop looking
 419                 if(!pkt || pkt->Sequence > Connection->NextSequenceRcv) {
 420                         RELEASE( &Connection->lFuturePackets );
 421                         return;
 422                 }
 423
 424                 // Delete packet from future list
 425                 if(prev)
 426                         prev->Next = pkt->Next;
 427                 else
 428                         Connection->FuturePackets = pkt->Next;
 429
 430                 // Release list
 431                 RELEASE( &Connection->lFuturePackets );
 432
 433                 // Looks like we found one
 434                 TCP_INT_AppendRecieved(Connection, pkt);
 435                 Connection->NextSequenceRcv += pkt->Length;
 436                 free(pkt);
 437         }
 438 }
 439
 440 /**
 441  * \fn Uint16 TCP_GetUnusedPort()
 442  * \brief Gets an unused port and allocates it
 443  */
 444 Uint16 TCP_GetUnusedPort()
 445 {
 446         Uint16  ret;
 447
 448         // Get Next outbound port
 449         ret = giTCP_NextOutPort++;
 450         while( gaTCP_PortBitmap[ret/32] & (1 << (ret%32)) )
 451         {
 452                 ret ++;
 453                 giTCP_NextOutPort++;
 454                 if(giTCP_NextOutPort == 0x10000) {
 455                         ret = giTCP_NextOutPort = TCP_MIN_DYNPORT;
 456                 }
 457         }
 458
 459         // Mark the new port as used
 460         gaTCP_PortBitmap[ret/32] |= 1 << (ret%32);
 461
 462         return ret;
 463 }
 464
 465 /**
 466  * \fn int TCP_AllocatePort(Uint16 Port)
 467  * \brief Marks a port as used
 468  */
 469 int TCP_AllocatePort(Uint16 Port)
 470 {
 471         // Check if the port has already been allocated
 472         if( gaTCP_PortBitmap[Port/32] & (1 << (Port%32)) )
 473                 return 0;
 474
 475         // Allocate
 476         gaTCP_PortBitmap[Port/32] |= 1 << (Port%32);
 477
 478         return 1;
 479 }
 480
 481 /**
 482  * \fn int TCP_DeallocatePort(Uint16 Port)
 483  * \brief Marks a port as unused
 484  */
 485 int TCP_DeallocatePort(Uint16 Port)
 486 {
 487         // Check if the port has already been allocated
 488         if( !(gaTCP_PortBitmap[Port/32] & (1 << (Port%32))) )
 489                 return 0;
 490
 491         // Allocate
 492         gaTCP_PortBitmap[Port/32] &= ~(1 << (Port%32));
 493
 494         return 1;
 495 }
 496
 497 // --- Server
 498 tVFS_Node *TCP_Server_Init(tInterface *Interface)
 499 {
 500         tTCPListener    *srv;
 501
 502         srv = malloc( sizeof(tTCPListener) );
 503
 504         if( srv == NULL ) {
 505                 Log_Warning("TCP", "malloc failed for listener (%i) bytes", sizeof(tTCPListener));
 506                 return NULL;
 507         }
 508
 509         srv->Interface = Interface;
 510         srv->Port = 0;
 511         srv->NextID = 0;
 512         srv->Connections = NULL;
 513         srv->ConnectionsTail = NULL;
 514         srv->NewConnections = NULL;
 515         srv->Next = NULL;
 516         srv->Node.Flags = VFS_FFLAG_DIRECTORY;
 517         srv->Node.Size = -1;
 518         srv->Node.ImplPtr = srv;
 519         srv->Node.NumACLs = 1;
 520         srv->Node.ACLs = &gVFS_ACL_EveryoneRW;
 521         srv->Node.ReadDir = TCP_Server_ReadDir;
 522         srv->Node.FindDir = TCP_Server_FindDir;
 523         srv->Node.IOCtl = TCP_Server_IOCtl;
 524         srv->Node.Close = TCP_Server_Close;
 525
 526         LOCK(&glTCP_Listeners);
 527         srv->Next = gTCP_Listeners;
 528         gTCP_Listeners = srv;
 529         RELEASE(&glTCP_Listeners);
 530
 531         return &srv->Node;
 532 }
 533
 534 /**
 535  * \brief Wait for a new connection and return the connection ID
 536  * \note Blocks until a new connection is made
 537  * \param Node  Server node
 538  * \param Pos   Position (ignored)
 539  */
 540 char *TCP_Server_ReadDir(tVFS_Node *Node, int Pos)
 541 {
 542         tTCPListener    *srv = Node->ImplPtr;
 543         tTCPConnection  *conn;
 544         char    *ret;
 545
 546         ENTER("pNode iPos", Node, Pos);
 547
 548         Log_Log("TCP", "Thread %i waiting for a connection", Threads_GetTID());
 549         for(;;)
 550         {
 551                 LOCK( &srv->lConnections );
 552                 if( srv->NewConnections != NULL )       break;
 553                 RELEASE( &srv->lConnections );
 554                 Threads_Yield();
 555                 continue;
 556         }
 557
 558
 559         // Increment the new list (the current connection is still on the
 560         // normal list)
 561         conn = srv->NewConnections;
 562         srv->NewConnections = conn->Next;
 563
 564         LOG("conn = %p", conn);
 565         LOG("srv->Connections = %p", srv->Connections);
 566         LOG("srv->NewConnections = %p", srv->NewConnections);
 567         LOG("srv->ConnectionsTail = %p", srv->ConnectionsTail);
 568
 569         RELEASE( &srv->lConnections );
 570
 571         ret = malloc(9);
 572         itoa(ret, conn->Node.ImplInt, 16, 8, '0');
 573         Log_Log("TCP", "Thread %i got '%s'", Threads_GetTID(), ret);
 574         LEAVE('s', ret);
 575         return ret;
 576 }
 577
 578 /**
 579  * \brief Gets a client connection node
 580  * \param Node  Server node
 581  * \param Name  Hexadecimal ID of the node
 582  */
 583 tVFS_Node *TCP_Server_FindDir(tVFS_Node *Node, char *Name)
 584 {
 585         tTCPConnection  *conn;
 586         tTCPListener    *srv = Node->ImplPtr;
 587         char    tmp[9];
 588          int    id = atoi(Name);
 589
 590         ENTER("pNode sName", Node, Name);
 591
 592         // Sanity Check
 593         itoa(tmp, id, 16, 8, '0');
 594         if(strcmp(tmp, Name) != 0) {
 595                 LOG("'%s' != '%s' (%08x)", Name, tmp, id);
 596                 LEAVE('n');
 597                 return NULL;
 598         }
 599
 600         Log_Debug("TCP", "srv->Connections = %p", srv->Connections);
 601         Log_Debug("TCP", "srv->NewConnections = %p", srv->NewConnections);
 602         Log_Debug("TCP", "srv->ConnectionsTail = %p", srv->ConnectionsTail);
 603
 604         // Search
 605         LOCK( &srv->lConnections );
 606         for(conn = srv->Connections;
 607                 conn;
 608                 conn = conn->Next)
 609         {
 610                 LOG("conn->Node.ImplInt = %i", conn->Node.ImplInt);
 611                 if(conn->Node.ImplInt == id)    break;
 612         }
 613         RELEASE( &srv->lConnections );
 614
 615         // If not found, ret NULL
 616         if(!conn) {
 617                 LOG("Connection %i not found", id);
 618                 LEAVE('n');
 619                 return NULL;
 620         }
 621
 622         // Return node
 623         LEAVE('p', &conn->Node);
 624         return &conn->Node;
 625 }
 626
 627 /**
 628  * \brief Handle IOCtl calls
 629  */
 630 int TCP_Server_IOCtl(tVFS_Node *Node, int ID, void *Data)
 631 {
 632         tTCPListener    *srv = Node->ImplPtr;
 633
 634         switch(ID)
 635         {
 636         case 4: // Get/Set Port
 637                 if(!Data)       // Get Port
 638                         return srv->Port;
 639
 640                 if(srv->Port)   // Wait, you can't CHANGE the port
 641                         return -1;
 642
 643                 if(!CheckMem(Data, sizeof(Uint16)))     // Sanity check
 644                         return -1;
 645
 646                 // Permissions check
 647                 if(Threads_GetUID() != 0
 648                 && *(Uint16*)Data != 0
 649                 && *(Uint16*)Data < 1024)
 650                         return -1;
 651
 652                 // TODO: Check if a port is in use
 653
 654                 // Set Port
 655                 srv->Port = *(Uint16*)Data;
 656                 if(srv->Port == 0)      // Allocate a random port
 657                         srv->Port = TCP_GetUnusedPort();
 658                 else    // Else, mark this as used
 659                         TCP_AllocatePort(srv->Port);
 660
 661                 Log_Log("TCP", "Server %p listening on port %i", srv, srv->Port);
 662
 663                 return srv->Port;
 664         }
 665         return 0;
 666 }
 667
 668 void TCP_Server_Close(tVFS_Node *Node)
 669 {
 670         free(Node->ImplPtr);
 671 }
 672
 673 // --- Client
 674 /**
 675  * \brief Create a client node
 676  */
 677 tVFS_Node *TCP_Client_Init(tInterface *Interface)
 678 {
 679         tTCPConnection  *conn = malloc( sizeof(tTCPConnection) );
 680
 681         conn->State = TCP_ST_CLOSED;
 682         conn->Interface = Interface;
 683         conn->LocalPort = 0;
 684         conn->RemotePort = 0;
 685         memset( &conn->RemoteIP, 0, sizeof(conn->RemoteIP) );
 686
 687         conn->Node.ImplPtr = conn;
 688         conn->Node.NumACLs = 1;
 689         conn->Node.ACLs = &gVFS_ACL_EveryoneRW;
 690         conn->Node.Read = TCP_Client_Read;
 691         conn->Node.Write = TCP_Client_Write;
 692         conn->Node.IOCtl = TCP_Client_IOCtl;
 693         conn->Node.Close = TCP_Client_Close;
 694
 695         LOCK(&glTCP_OutbountCons);
 696         conn->Next = gTCP_OutbountCons;
 697         gTCP_OutbountCons = conn;
 698         RELEASE(&glTCP_OutbountCons);
 699
 700         return &conn->Node;
 701 }
 702
 703 /**
 704  * \brief Wait for a packet and return it
 705  * \note If \a Length is smaller than the size of the packet, the rest
 706  *       of the packet's data will be discarded.
 707  */
 708 Uint64 TCP_Client_Read(tVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer)
 709 {
 710         tTCPConnection  *conn = Node->ImplPtr;
 711         char    *destbuf = Buffer;
 712         size_t  len;
 713
 714         ENTER("pNode XOffset XLength pBuffer", Node, Offset, Length, Buffer);
 715
 716         // Check if connection is open
 717         if( conn->State != TCP_ST_OPEN ) {
 718                 LEAVE('i', 0);
 719                 return 0;
 720         }
 721
 722         // Poll packets
 723         for(;;)
 724         {
 725                 // Lock list and check if there is a packet
 726                 LOCK( &conn->lRecievedPackets );
 727                 if( conn->RecievedBuffer->Length == 0 ) {
 728                         // If not, release the lock, yield and try again
 729                         RELEASE( &conn->lRecievedPackets );
 730                         Threads_Yield();
 731                         continue;
 732                 }
 733
 734                 // Attempt to read all `Length` bytes
 735                 len = RingBuffer_Read( destbuf, conn->RecievedBuffer, Length );
 736
 737                 // Release the lock (we don't need it any more)
 738                 RELEASE( &conn->lRecievedPackets );
 739
 740                 LEAVE('i', len);
 741                 return len;
 742         }
 743 }
 744
 745 /**
 746  * \brief Send a data packet on a connection
 747  */
 748 void TCP_INT_SendDataPacket(tTCPConnection *Connection, size_t Length, void *Data)
 749 {
 750         char    buf[sizeof(tTCPHeader)+Length];
 751         tTCPHeader      *packet = (void*)buf;
 752
 753         packet->SourcePort = htons(Connection->LocalPort);
 754         packet->DestPort = htons(Connection->RemotePort);
 755         packet->DataOffset = (sizeof(tTCPHeader)/4)*16;
 756         packet->WindowSize = TCP_WINDOW_SIZE;
 757
 758         //packet->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 759         packet->AcknowlegementNumber = 0;
 760         packet->SequenceNumber = htonl(Connection->NextSequenceSend);
 761         //packet->Flags = TCP_FLAG_PSH; // Hey, ACK if you can!
 762
 763         memcpy(packet->Options, Data, Length);
 764
 765         TCP_SendPacket( Connection, sizeof(tTCPHeader)+Length, packet );
 766
 767         Connection->NextSequenceSend += Length;
 768 }
 769
 770 /**
 771  * \brief Send some bytes on a connection
 772  */
 773 Uint64 TCP_Client_Write(tVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer)
 774 {
 775         tTCPConnection  *conn = Node->ImplPtr;
 776         size_t  rem = Length;
 777
 778         ENTER("pNode XOffset XLength pBuffer", Node, Offset, Length, Buffer);
 779
 780         // Check if connection is open
 781         if( conn->State != TCP_ST_OPEN ) {
 782                 LEAVE('i', 0);
 783                 return 0;
 784         }
 785
 786         while( rem > TCP_MAX_PACKET_SIZE )
 787         {
 788                 TCP_INT_SendDataPacket(conn, TCP_MAX_PACKET_SIZE, Buffer);
 789                 Buffer += TCP_MAX_PACKET_SIZE;
 790         }
 791
 792         TCP_INT_SendDataPacket(conn, rem, Buffer);
 793
 794         LEAVE('i', Length);
 795         return Length;
 796 }
 797
 798 /**
 799  * \brief Control a client socket
 800  */
 801 int TCP_Client_IOCtl(tVFS_Node *Node, int ID, void *Data)
 802 {
 803         tTCPConnection  *conn = Node->ImplPtr;
 804
 805         switch(ID)
 806         {
 807         case 4: // Get/Set local port
 808                 if(!Data)
 809                         return conn->LocalPort;
 810                 if(conn->State != TCP_ST_CLOSED)
 811                         return -1;
 812                 if(!CheckMem(Data, sizeof(Uint16)))
 813                         return -1;
 814
 815                 if(Threads_GetUID() != 0 && *(Uint16*)Data < 1024)
 816                         return -1;
 817
 818                 conn->LocalPort = *(Uint16*)Data;
 819                 return 0;
 820
 821         case 5: // Get/Set remote port
 822                 if(!Data)       return conn->RemotePort;
 823                 if(conn->State != TCP_ST_CLOSED)        return -1;
 824                 if(!CheckMem(Data, sizeof(Uint16)))     return -1;
 825                 conn->RemotePort = *(Uint16*)Data;
 826                 return 0;
 827
 828         case 6: // Set Remote IP
 829                 if( conn->State != TCP_ST_CLOSED )
 830                         return -1;
 831                 if( conn->Interface->Type == 4 )
 832                 {
 833                         if(!CheckMem(Data, sizeof(tIPv4)))      return -1;
 834                         conn->RemoteIP.v4 = *(tIPv4*)Data;
 835                 }
 836                 else if( conn->Interface->Type == 6 )
 837                 {
 838                         if(!CheckMem(Data, sizeof(tIPv6)))      return -1;
 839                         conn->RemoteIP.v6 = *(tIPv6*)Data;
 840                 }
 841                 return 0;
 842
 843         case 7: // Connect
 844                 if(conn->LocalPort == -1)
 845                         conn->LocalPort = TCP_GetUnusedPort();
 846                 if(conn->RemotePort == -1)
 847                         return 0;
 848
 849                 TCP_StartConnection(conn);
 850                 return 1;
 851         }
 852
 853         return 0;
 854 }
 855
 856 void TCP_Client_Close(tVFS_Node *Node)
 857 {
 858         free(Node->ImplPtr);
 859 }