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, const 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 tShortSpinlock  glTCP_Listeners;
  48 tTCPListener    *gTCP_Listeners;
  49 tShortSpinlock  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 Sends a packet from the specified connection, calculating the checksums
  69  * \param Conn  Connection
  70  * \param Length        Length of data
  71  * \param Data  Packet data (cast as a TCP Header)
  72  */
  73 void TCP_SendPacket( tTCPConnection *Conn, size_t Length, tTCPHeader *Data )
  74 {
  75         size_t  buflen;
  76         Uint32  *buf;
  77         switch( Conn->Interface->Type )
  78         {
  79         case 4: // Append IPv4 Pseudo Header
  80                 buflen = 4 + 4 + 4 + ((Length+1)&~1);
  81                 buf = malloc( buflen );
  82                 buf[0] = ((tIPv4*)Conn->Interface->Address)->L;
  83                 buf[1] = Conn->RemoteIP.v4.L;
  84                 buf[2] = (htons(Length)<<16) | (6<<8) | 0;
  85                 Data->Checksum = 0;
  86                 memcpy( &buf[3], Data, Length );
  87                 Data->Checksum = IPv4_Checksum( buf, buflen );
  88                 free(buf);
  89                 IPv4_SendPacket(Conn->Interface, Conn->RemoteIP.v4, IP4PROT_TCP, 0, Length, Data);
  90                 break;
  91         }
  92 }
  93
  94 /**
  95  * \brief Handles a packet from the IP Layer
  96  * \param Interface     Interface the packet arrived from
  97  * \param Address       Pointer to the addres structure
  98  * \param Length        Size of packet in bytes
  99  * \param Buffer        Packet data
 100  */
 101 void TCP_GetPacket(tInterface *Interface, void *Address, int Length, void *Buffer)
 102 {
 103         tTCPHeader      *hdr = Buffer;
 104         tTCPListener    *srv;
 105         tTCPConnection  *conn;
 106
 107         Log_Log("TCP", "SourcePort = %i, DestPort = %i",
 108                 ntohs(hdr->SourcePort), ntohs(hdr->DestPort));
 109 /*
 110         Log_Log("TCP", "SequenceNumber = 0x%x", ntohl(hdr->SequenceNumber));
 111         Log_Log("TCP", "AcknowlegementNumber = 0x%x", ntohl(hdr->AcknowlegementNumber));
 112         Log_Log("TCP", "DataOffset = %i", hdr->DataOffset >> 4);
 113         Log_Log("TCP", "Flags = {");
 114         Log_Log("TCP", "  CWR = %B, ECE = %B",
 115                 !!(hdr->Flags & TCP_FLAG_CWR), !!(hdr->Flags & TCP_FLAG_ECE));
 116         Log_Log("TCP", "  URG = %B, ACK = %B",
 117                 !!(hdr->Flags & TCP_FLAG_URG), !!(hdr->Flags & TCP_FLAG_ACK));
 118         Log_Log("TCP", "  PSH = %B, RST = %B",
 119                 !!(hdr->Flags & TCP_FLAG_PSH), !!(hdr->Flags & TCP_FLAG_RST));
 120         Log_Log("TCP", "  SYN = %B, FIN = %B",
 121                 !!(hdr->Flags & TCP_FLAG_SYN), !!(hdr->Flags & TCP_FLAG_FIN));
 122         Log_Log("TCP", "}");
 123         Log_Log("TCP", "WindowSize = %i", htons(hdr->WindowSize));
 124         Log_Log("TCP", "Checksum = 0x%x", htons(hdr->Checksum));
 125         Log_Log("TCP", "UrgentPointer = 0x%x", htons(hdr->UrgentPointer));
 126 */
 127         Log_Log("TCP", "Flags = %s%s%s%s%s%s",
 128                 (hdr->Flags & TCP_FLAG_CWR) ? "CWR " : "",
 129                 (hdr->Flags & TCP_FLAG_ECE) ? "ECE " : "",
 130                 (hdr->Flags & TCP_FLAG_URG) ? "URG " : "",
 131                 (hdr->Flags & TCP_FLAG_ACK) ? "ACK " : "",
 132                 (hdr->Flags & TCP_FLAG_PSH) ? "PSH " : "",
 133                 (hdr->Flags & TCP_FLAG_RST) ? "RST " : "",
 134                 (hdr->Flags & TCP_FLAG_SYN) ? "SYN " : "",
 135                 (hdr->Flags & TCP_FLAG_FIN) ? "FIN " : ""
 136                 );
 137
 138         if( Length > (hdr->DataOffset >> 4)*4 )
 139         {
 140                 Debug_HexDump(
 141                         "[TCP  ] Packet Data = ",
 142                         (Uint8*)hdr + (hdr->DataOffset >> 4)*4,
 143                         Length - (hdr->DataOffset >> 4)*4
 144                         );
 145         }
 146
 147         // Check Servers
 148         {
 149                 for( srv = gTCP_Listeners; srv; srv = srv->Next )
 150                 {
 151                         // Check if the server is active
 152                         if(srv->Port == 0)      continue;
 153                         // Check the interface
 154                         if(srv->Interface && srv->Interface != Interface)       continue;
 155                         // Check the destination port
 156                         if(srv->Port != htons(hdr->DestPort))   continue;
 157
 158                         Log_Log("TCP", "Matches server %p", srv);
 159                         // Is this in an established connection?
 160                         for( conn = srv->Connections; conn; conn = conn->Next )
 161                         {
 162                                 Log_Log("TCP", "conn->Interface(%p) == Interface(%p)",
 163                                         conn->Interface, Interface);
 164                                 // Check that it is coming in on the same interface
 165                                 if(conn->Interface != Interface)        continue;
 166
 167                                 // Check Source Port
 168                                 Log_Log("TCP", "conn->RemotePort(%i) == hdr->SourcePort(%i)",
 169                                         conn->RemotePort, ntohs(hdr->SourcePort));
 170                                 if(conn->RemotePort != ntohs(hdr->SourcePort))  continue;
 171
 172                                 // Check Source IP
 173                                 if(conn->Interface->Type == 6 && !IP6_EQU(conn->RemoteIP.v6, *(tIPv6*)Address))
 174                                         continue;
 175                                 if(conn->Interface->Type == 4 && !IP4_EQU(conn->RemoteIP.v4, *(tIPv4*)Address))
 176                                         continue;
 177
 178                                 Log_Log("TCP", "Matches connection %p", conn);
 179                                 // We have a response!
 180                                 TCP_INT_HandleConnectionPacket(conn, hdr, Length);
 181
 182                                 return;
 183                         }
 184
 185                         Log_Log("TCP", "Opening Connection");
 186                         // Open a new connection (well, check that it's a SYN)
 187                         if(hdr->Flags != TCP_FLAG_SYN) {
 188                                 Log_Log("TCP", "Packet is not a SYN");
 189                                 return ;
 190                         }
 191
 192                         // TODO: Check for halfopen max
 193
 194                         conn = calloc(1, sizeof(tTCPConnection));
 195                         conn->State = TCP_ST_HALFOPEN;
 196                         conn->LocalPort = srv->Port;
 197                         conn->RemotePort = ntohs(hdr->SourcePort);
 198                         conn->Interface = Interface;
 199
 200                         switch(Interface->Type)
 201                         {
 202                         case 4: conn->RemoteIP.v4 = *(tIPv4*)Address;   break;
 203                         case 6: conn->RemoteIP.v6 = *(tIPv6*)Address;   break;
 204                         }
 205
 206                         conn->RecievedBuffer = RingBuffer_Create( TCP_RECIEVE_BUFFER_SIZE );
 207
 208                         conn->NextSequenceRcv = ntohl( hdr->SequenceNumber ) + 1;
 209                         conn->NextSequenceSend = rand();
 210
 211                         // Create node
 212                         conn->Node.NumACLs = 1;
 213                         conn->Node.ACLs = &gVFS_ACL_EveryoneRW;
 214                         conn->Node.ImplPtr = conn;
 215                         conn->Node.ImplInt = srv->NextID ++;
 216                         conn->Node.Read = TCP_Client_Read;
 217                         conn->Node.Write = TCP_Client_Write;
 218                         //conn->Node.Close = TCP_SrvConn_Close;
 219
 220                         // Hmm... Theoretically, this lock will never have to wait,
 221                         // as the interface is locked to the watching thread, and this
 222                         // runs in the watching thread. But, it's a good idea to have
 223                         // it, just in case
 224                         // Oh, wait, there is a case where a wildcard can be used
 225                         // (srv->Interface == NULL) so having the lock is a good idea
 226                         SHORTLOCK(&srv->lConnections);
 227                         if( !srv->Connections )
 228                                 srv->Connections = conn;
 229                         else
 230                                 srv->ConnectionsTail->Next = conn;
 231                         srv->ConnectionsTail = conn;
 232                         if(!srv->NewConnections)
 233                                 srv->NewConnections = conn;
 234                         SHORTREL(&srv->lConnections);
 235
 236                         // Send the SYN ACK
 237                         hdr->Flags |= TCP_FLAG_ACK;
 238                         hdr->AcknowlegementNumber = htonl(conn->NextSequenceRcv);
 239                         hdr->SequenceNumber = htonl(conn->NextSequenceSend);
 240                         hdr->DestPort = hdr->SourcePort;
 241                         hdr->SourcePort = htons(srv->Port);
 242                         hdr->DataOffset = (sizeof(tTCPHeader)/4) << 4;
 243                         TCP_SendPacket( conn, sizeof(tTCPHeader), hdr );
 244                         conn->NextSequenceSend ++;
 245                         return ;
 246                 }
 247         }
 248
 249
 250         // Check Open Connections
 251         {
 252                 for( conn = gTCP_OutbountCons; conn; conn = conn->Next )
 253                 {
 254                         // Check that it is coming in on the same interface
 255                         if(conn->Interface != Interface)        continue;
 256
 257                         // Check Source Port
 258                         if(conn->RemotePort != ntohs(hdr->SourcePort))  continue;
 259
 260                         // Check Source IP
 261                         if(conn->Interface->Type == 6 && !IP6_EQU(conn->RemoteIP.v6, *(tIPv6*)Address))
 262                                 continue;
 263                         if(conn->Interface->Type == 4 && !IP4_EQU(conn->RemoteIP.v4, *(tIPv4*)Address))
 264                                 continue;
 265
 266                         TCP_INT_HandleConnectionPacket(conn, hdr, Length);
 267                         return ;
 268                 }
 269         }
 270
 271         Log_Log("TCP", "No Match");
 272 }
 273
 274 /**
 275  * \brief Handles a packet sent to a specific connection
 276  * \param Connection    TCP Connection pointer
 277  * \param Header        TCP Packet pointer
 278  * \param Length        Length of the packet
 279  */
 280 void TCP_INT_HandleConnectionPacket(tTCPConnection *Connection, tTCPHeader *Header, int Length)
 281 {
 282         tTCPStoredPacket        *pkt;
 283          int    dataLen;
 284
 285         if(Header->Flags & TCP_FLAG_SYN) {
 286                 Connection->NextSequenceRcv = ntohl(Header->SequenceNumber) + 1;
 287         }
 288
 289         if( Connection->State == TCP_ST_SYN_SENT )
 290         {
 291                 if( (Header->Flags & (TCP_FLAG_SYN|TCP_FLAG_ACK)) == (TCP_FLAG_SYN|TCP_FLAG_ACK) ) {
 292
 293                         Header->DestPort = Header->SourcePort;
 294                         Header->SourcePort = htons(Connection->LocalPort);
 295                         Header->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 296                         Header->SequenceNumber = htonl(Connection->NextSequenceSend);
 297                         Header->WindowSize = htons(TCP_WINDOW_SIZE);
 298                         Header->Flags = TCP_FLAG_ACK;
 299                         Header->DataOffset = (sizeof(tTCPHeader)/4) << 4;
 300                         Log_Log("TCP", "ACKing SYN-ACK");
 301                         TCP_SendPacket( Connection, sizeof(tTCPHeader), Header );
 302                         Connection->State = TCP_ST_OPEN;
 303                 }
 304         }
 305
 306         // Get length of data
 307         dataLen = Length - (Header->DataOffset>>4)*4;
 308         Log_Log("TCP", "HandleConnectionPacket - dataLen = %i", dataLen);
 309
 310         if(Header->Flags & TCP_FLAG_ACK) {
 311                 // TODO: Process an ACKed Packet
 312                 Log_Log("TCP", "Conn %p, Packet 0x%x ACKed", Connection, Header->AcknowlegementNumber);
 313         }
 314
 315         // TODO: Check what to do here
 316         if(Header->Flags & TCP_FLAG_FIN) {
 317                 if( Connection->State == TCP_ST_FIN_SENT ) {
 318                         Connection->State = TCP_ST_FINISHED;
 319                         return ;
 320                 }
 321                 else {
 322                         Connection->State = TCP_ST_FINISHED;
 323                         Header->DestPort = Header->SourcePort;
 324                         Header->SourcePort = htons(Connection->LocalPort);
 325                         Header->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 326                         Header->SequenceNumber = htonl(Connection->NextSequenceSend);
 327                         Header->Flags = TCP_FLAG_ACK;
 328                         TCP_SendPacket( Connection, sizeof(tTCPHeader), Header );
 329                         return ;
 330                 }
 331         }
 332
 333         if(dataLen == 0) {
 334                 Log_Log("TCP", "Empty Packet");
 335                 return ;
 336         }
 337
 338         // NOTES:
 339         // Flags
 340         //    PSH - Has Data?
 341         // /NOTES
 342
 343         // Allocate and fill cached packet
 344         pkt = malloc( dataLen + sizeof(tTCPStoredPacket) );
 345         pkt->Next = NULL;
 346         pkt->Sequence = ntohl(Header->SequenceNumber);
 347         pkt->Length = dataLen;
 348         memcpy(pkt->Data, (Uint8*)Header + (Header->DataOffset>>4)*4, dataLen);
 349
 350         // Is this packet the next expected packet?
 351         // TODO: Fix this to check if the packet is in the window.
 352         if( pkt->Sequence != Connection->NextSequenceRcv )
 353         {
 354                 tTCPStoredPacket        *tmp, *prev = NULL;
 355
 356                 Log_Log("TCP", "Out of sequence packet (0x%08x != 0x%08x)",
 357                         pkt->Sequence, Connection->NextSequenceRcv);
 358
 359                 // No? Well, let's cache it and look at it later
 360                 SHORTLOCK( &Connection->lFuturePackets );
 361                 for(tmp = Connection->FuturePackets;
 362                         tmp;
 363                         prev = tmp, tmp = tmp->Next)
 364                 {
 365                         if(tmp->Sequence > pkt->Sequence)       break;
 366                 }
 367                 if(prev)
 368                         prev->Next = pkt;
 369                 else
 370                         Connection->FuturePackets = pkt;
 371                 pkt->Next = tmp;
 372                 SHORTREL( &Connection->lFuturePackets );
 373         }
 374         else
 375         {
 376                 // Ooh, Goodie! Add it to the recieved list
 377                 TCP_INT_AppendRecieved(Connection, pkt);
 378                 free(pkt);
 379                 Log_Log("TCP", "0x%08x += %i", Connection->NextSequenceRcv, dataLen);
 380                 Connection->NextSequenceRcv += dataLen;
 381
 382                 // TODO: This should be moved out of the watcher thread,
 383                 // so that a single lost packet on one connection doesn't cause
 384                 // all connections on the interface to lag.
 385                 TCP_INT_UpdateRecievedFromFuture(Connection);
 386
 387                 // ACK Packet
 388                 Header->DestPort = Header->SourcePort;
 389                 Header->SourcePort = htons(Connection->LocalPort);
 390                 Header->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 391                 Header->SequenceNumber = htonl(Connection->NextSequenceSend);
 392                 Header->WindowSize = htons(TCP_WINDOW_SIZE);
 393                 Header->Flags &= TCP_FLAG_SYN;  // Eliminate all flags save for SYN
 394                 Header->Flags |= TCP_FLAG_ACK;  // Add ACK
 395                 Log_Log("TCP", "Sending ACK for 0x%08x", Connection->NextSequenceRcv);
 396                 TCP_SendPacket( Connection, sizeof(tTCPHeader), Header );
 397                 //Connection->NextSequenceSend ++;
 398         }
 399 }
 400
 401 /**
 402  * \brief Appends a packet to the recieved list
 403  * \param Connection    Connection structure
 404  * \param Pkt   Packet structure on heap
 405  */
 406 void TCP_INT_AppendRecieved(tTCPConnection *Connection, tTCPStoredPacket *Pkt)
 407 {
 408         Mutex_Acquire( &Connection->lRecievedPackets );
 409         if(Connection->RecievedBuffer->Length + Pkt->Length > Connection->RecievedBuffer->Space )
 410         {
 411                 Log_Error("TCP", "Buffer filled, packet dropped (%s)",
 412                 //      TCP_INT_DumpConnection(Connection)
 413                         ""
 414                         );
 415                 return ;
 416         }
 417
 418         RingBuffer_Write( Connection->RecievedBuffer, Pkt->Data, Pkt->Length );
 419
 420         Mutex_Release( &Connection->lRecievedPackets );
 421 }
 422
 423 /**
 424  * \brief Updates the connections recieved list from the future list
 425  * \param Connection    Connection structure
 426  *
 427  * Updates the recieved packets list with packets from the future (out
 428  * of order) packets list that are now able to be added in direct
 429  * sequence.
 430  */
 431 void TCP_INT_UpdateRecievedFromFuture(tTCPConnection *Connection)
 432 {
 433         tTCPStoredPacket        *pkt, *prev;
 434         for(;;)
 435         {
 436                 prev = NULL;
 437                 // Look for the next expected packet in the cache.
 438                 SHORTLOCK( &Connection->lFuturePackets );
 439                 for(pkt = Connection->FuturePackets;
 440                         pkt && pkt->Sequence < Connection->NextSequenceRcv;
 441                         prev = pkt, pkt = pkt->Next);
 442
 443                 // If we can't find the expected next packet, stop looking
 444                 if(!pkt || pkt->Sequence > Connection->NextSequenceRcv) {
 445                         SHORTREL( &Connection->lFuturePackets );
 446                         return;
 447                 }
 448
 449                 // Delete packet from future list
 450                 if(prev)
 451                         prev->Next = pkt->Next;
 452                 else
 453                         Connection->FuturePackets = pkt->Next;
 454
 455                 // Release list
 456                 SHORTREL( &Connection->lFuturePackets );
 457
 458                 // Looks like we found one
 459                 TCP_INT_AppendRecieved(Connection, pkt);
 460                 Connection->NextSequenceRcv += pkt->Length;
 461                 free(pkt);
 462         }
 463 }
 464
 465 /**
 466  * \fn Uint16 TCP_GetUnusedPort()
 467  * \brief Gets an unused port and allocates it
 468  */
 469 Uint16 TCP_GetUnusedPort()
 470 {
 471         Uint16  ret;
 472
 473         // Get Next outbound port
 474         ret = giTCP_NextOutPort++;
 475         while( gaTCP_PortBitmap[ret/32] & (1 << (ret%32)) )
 476         {
 477                 ret ++;
 478                 giTCP_NextOutPort++;
 479                 if(giTCP_NextOutPort == 0x10000) {
 480                         ret = giTCP_NextOutPort = TCP_MIN_DYNPORT;
 481                 }
 482         }
 483
 484         // Mark the new port as used
 485         gaTCP_PortBitmap[ret/32] |= 1 << (ret%32);
 486
 487         return ret;
 488 }
 489
 490 /**
 491  * \fn int TCP_AllocatePort(Uint16 Port)
 492  * \brief Marks a port as used
 493  */
 494 int TCP_AllocatePort(Uint16 Port)
 495 {
 496         // Check if the port has already been allocated
 497         if( gaTCP_PortBitmap[Port/32] & (1 << (Port%32)) )
 498                 return 0;
 499
 500         // Allocate
 501         gaTCP_PortBitmap[Port/32] |= 1 << (Port%32);
 502
 503         return 1;
 504 }
 505
 506 /**
 507  * \fn int TCP_DeallocatePort(Uint16 Port)
 508  * \brief Marks a port as unused
 509  */
 510 int TCP_DeallocatePort(Uint16 Port)
 511 {
 512         // Check if the port has already been allocated
 513         if( !(gaTCP_PortBitmap[Port/32] & (1 << (Port%32))) )
 514                 return 0;
 515
 516         // Allocate
 517         gaTCP_PortBitmap[Port/32] &= ~(1 << (Port%32));
 518
 519         return 1;
 520 }
 521
 522 // --- Server
 523 tVFS_Node *TCP_Server_Init(tInterface *Interface)
 524 {
 525         tTCPListener    *srv;
 526
 527         srv = malloc( sizeof(tTCPListener) );
 528
 529         if( srv == NULL ) {
 530                 Log_Warning("TCP", "malloc failed for listener (%i) bytes", sizeof(tTCPListener));
 531                 return NULL;
 532         }
 533
 534         srv->Interface = Interface;
 535         srv->Port = 0;
 536         srv->NextID = 0;
 537         srv->Connections = NULL;
 538         srv->ConnectionsTail = NULL;
 539         srv->NewConnections = NULL;
 540         srv->Next = NULL;
 541         srv->Node.Flags = VFS_FFLAG_DIRECTORY;
 542         srv->Node.Size = -1;
 543         srv->Node.ImplPtr = srv;
 544         srv->Node.NumACLs = 1;
 545         srv->Node.ACLs = &gVFS_ACL_EveryoneRW;
 546         srv->Node.ReadDir = TCP_Server_ReadDir;
 547         srv->Node.FindDir = TCP_Server_FindDir;
 548         srv->Node.IOCtl = TCP_Server_IOCtl;
 549         srv->Node.Close = TCP_Server_Close;
 550
 551         SHORTLOCK(&glTCP_Listeners);
 552         srv->Next = gTCP_Listeners;
 553         gTCP_Listeners = srv;
 554         SHORTREL(&glTCP_Listeners);
 555
 556         return &srv->Node;
 557 }
 558
 559 /**
 560  * \brief Wait for a new connection and return the connection ID
 561  * \note Blocks until a new connection is made
 562  * \param Node  Server node
 563  * \param Pos   Position (ignored)
 564  */
 565 char *TCP_Server_ReadDir(tVFS_Node *Node, int Pos)
 566 {
 567         tTCPListener    *srv = Node->ImplPtr;
 568         tTCPConnection  *conn;
 569         char    *ret;
 570
 571         ENTER("pNode iPos", Node, Pos);
 572
 573         Log_Log("TCP", "Thread %i waiting for a connection", Threads_GetTID());
 574         for(;;)
 575         {
 576                 SHORTLOCK( &srv->lConnections );
 577                 if( srv->NewConnections != NULL )       break;
 578                 SHORTREL( &srv->lConnections );
 579                 Threads_Yield();        // TODO: Sleep until poked
 580                 continue;
 581         }
 582
 583
 584         // Increment the new list (the current connection is still on the
 585         // normal list)
 586         conn = srv->NewConnections;
 587         srv->NewConnections = conn->Next;
 588
 589         SHORTREL( &srv->lConnections );
 590
 591         LOG("conn = %p", conn);
 592         LOG("srv->Connections = %p", srv->Connections);
 593         LOG("srv->NewConnections = %p", srv->NewConnections);
 594         LOG("srv->ConnectionsTail = %p", srv->ConnectionsTail);
 595
 596         ret = malloc(9);
 597         itoa(ret, conn->Node.ImplInt, 16, 8, '0');
 598         Log_Log("TCP", "Thread %i got '%s'", Threads_GetTID(), ret);
 599         LEAVE('s', ret);
 600         return ret;
 601 }
 602
 603 /**
 604  * \brief Gets a client connection node
 605  * \param Node  Server node
 606  * \param Name  Hexadecimal ID of the node
 607  */
 608 tVFS_Node *TCP_Server_FindDir(tVFS_Node *Node, const char *Name)
 609 {
 610         tTCPConnection  *conn;
 611         tTCPListener    *srv = Node->ImplPtr;
 612         char    tmp[9];
 613          int    id = atoi(Name);
 614
 615         ENTER("pNode sName", Node, Name);
 616
 617         // Sanity Check
 618         itoa(tmp, id, 16, 8, '0');
 619         if(strcmp(tmp, Name) != 0) {
 620                 LOG("'%s' != '%s' (%08x)", Name, tmp, id);
 621                 LEAVE('n');
 622                 return NULL;
 623         }
 624
 625         Log_Debug("TCP", "srv->Connections = %p", srv->Connections);
 626         Log_Debug("TCP", "srv->NewConnections = %p", srv->NewConnections);
 627         Log_Debug("TCP", "srv->ConnectionsTail = %p", srv->ConnectionsTail);
 628
 629         // Search
 630         SHORTLOCK( &srv->lConnections );
 631         for(conn = srv->Connections;
 632                 conn;
 633                 conn = conn->Next)
 634         {
 635                 LOG("conn->Node.ImplInt = %i", conn->Node.ImplInt);
 636                 if(conn->Node.ImplInt == id)    break;
 637         }
 638         SHORTREL( &srv->lConnections );
 639
 640         // If not found, ret NULL
 641         if(!conn) {
 642                 LOG("Connection %i not found", id);
 643                 LEAVE('n');
 644                 return NULL;
 645         }
 646
 647         // Return node
 648         LEAVE('p', &conn->Node);
 649         return &conn->Node;
 650 }
 651
 652 /**
 653  * \brief Handle IOCtl calls
 654  */
 655 int TCP_Server_IOCtl(tVFS_Node *Node, int ID, void *Data)
 656 {
 657         tTCPListener    *srv = Node->ImplPtr;
 658
 659         switch(ID)
 660         {
 661         case 4: // Get/Set Port
 662                 if(!Data)       // Get Port
 663                         return srv->Port;
 664
 665                 if(srv->Port)   // Wait, you can't CHANGE the port
 666                         return -1;
 667
 668                 if(!CheckMem(Data, sizeof(Uint16)))     // Sanity check
 669                         return -1;
 670
 671                 // Permissions check
 672                 if(Threads_GetUID() != 0
 673                 && *(Uint16*)Data != 0
 674                 && *(Uint16*)Data < 1024)
 675                         return -1;
 676
 677                 // TODO: Check if a port is in use
 678
 679                 // Set Port
 680                 srv->Port = *(Uint16*)Data;
 681                 if(srv->Port == 0)      // Allocate a random port
 682                         srv->Port = TCP_GetUnusedPort();
 683                 else    // Else, mark this as used
 684                         TCP_AllocatePort(srv->Port);
 685
 686                 Log_Log("TCP", "Server %p listening on port %i", srv, srv->Port);
 687
 688                 return srv->Port;
 689         }
 690         return 0;
 691 }
 692
 693 void TCP_Server_Close(tVFS_Node *Node)
 694 {
 695         free(Node->ImplPtr);
 696 }
 697
 698 // --- Client
 699 /**
 700  * \brief Create a client node
 701  */
 702 tVFS_Node *TCP_Client_Init(tInterface *Interface)
 703 {
 704         tTCPConnection  *conn = malloc( sizeof(tTCPConnection) );
 705
 706         conn->State = TCP_ST_CLOSED;
 707         conn->Interface = Interface;
 708         conn->LocalPort = -1;
 709         conn->RemotePort = -1;
 710         memset( &conn->RemoteIP, 0, sizeof(conn->RemoteIP) );
 711
 712         conn->Node.ImplPtr = conn;
 713         conn->Node.NumACLs = 1;
 714         conn->Node.ACLs = &gVFS_ACL_EveryoneRW;
 715         conn->Node.Read = TCP_Client_Read;
 716         conn->Node.Write = TCP_Client_Write;
 717         conn->Node.IOCtl = TCP_Client_IOCtl;
 718         conn->Node.Close = TCP_Client_Close;
 719
 720         conn->RecievedBuffer = RingBuffer_Create( TCP_RECIEVE_BUFFER_SIZE );
 721
 722         SHORTLOCK(&glTCP_OutbountCons);
 723         conn->Next = gTCP_OutbountCons;
 724         gTCP_OutbountCons = conn;
 725         SHORTREL(&glTCP_OutbountCons);
 726
 727         return &conn->Node;
 728 }
 729
 730 /**
 731  * \brief Wait for a packet and return it
 732  * \note If \a Length is smaller than the size of the packet, the rest
 733  *       of the packet's data will be discarded.
 734  */
 735 Uint64 TCP_Client_Read(tVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer)
 736 {
 737         tTCPConnection  *conn = Node->ImplPtr;
 738         char    *destbuf = Buffer;
 739         size_t  len;
 740
 741         ENTER("pNode XOffset XLength pBuffer", Node, Offset, Length, Buffer);
 742         LOG("conn = %p", conn);
 743         LOG("conn->State = %i", conn->State);
 744
 745         // Check if connection is open
 746         while( conn->State == TCP_ST_HALFOPEN || conn->State == TCP_ST_SYN_SENT )
 747                 Threads_Yield();
 748         if( conn->State != TCP_ST_OPEN ) {
 749                 LEAVE('i', 0);
 750                 return 0;
 751         }
 752
 753         // Poll packets
 754         for(;;)
 755         {
 756                 // Lock list and check if there is a packet
 757                 Mutex_Acquire( &conn->lRecievedPackets );
 758                 if( conn->RecievedBuffer->Length == 0 ) {
 759                         // If not, release the lock, yield and try again
 760                         Mutex_Release( &conn->lRecievedPackets );
 761                         Threads_Yield();        // TODO: Less expensive wait
 762                         continue;
 763                 }
 764
 765                 // Attempt to read all `Length` bytes
 766                 len = RingBuffer_Read( destbuf, conn->RecievedBuffer, Length );
 767
 768                 // Release the lock (we don't need it any more)
 769                 Mutex_Release( &conn->lRecievedPackets );
 770
 771                 LEAVE('i', len);
 772                 return len;
 773         }
 774 }
 775
 776 /**
 777  * \brief Send a data packet on a connection
 778  */
 779 void TCP_INT_SendDataPacket(tTCPConnection *Connection, size_t Length, void *Data)
 780 {
 781         char    buf[sizeof(tTCPHeader)+Length];
 782         tTCPHeader      *packet = (void*)buf;
 783
 784         packet->SourcePort = htons(Connection->LocalPort);
 785         packet->DestPort = htons(Connection->RemotePort);
 786         packet->DataOffset = (sizeof(tTCPHeader)/4)*16;
 787         packet->WindowSize = TCP_WINDOW_SIZE;
 788
 789         packet->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 790         packet->SequenceNumber = htonl(Connection->NextSequenceSend);
 791         packet->Flags = TCP_FLAG_PSH|TCP_FLAG_ACK;      // Hey, ACK if you can!
 792
 793         memcpy(packet->Options, Data, Length);
 794
 795         TCP_SendPacket( Connection, sizeof(tTCPHeader)+Length, packet );
 796
 797         Connection->NextSequenceSend += Length;
 798 }
 799
 800 /**
 801  * \brief Send some bytes on a connection
 802  */
 803 Uint64 TCP_Client_Write(tVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer)
 804 {
 805         tTCPConnection  *conn = Node->ImplPtr;
 806         size_t  rem = Length;
 807
 808         ENTER("pNode XOffset XLength pBuffer", Node, Offset, Length, Buffer);
 809
 810         // Check if connection is open
 811         while( conn->State == TCP_ST_HALFOPEN || conn->State == TCP_ST_SYN_SENT )
 812                 Threads_Yield();
 813         if( conn->State != TCP_ST_OPEN ) {
 814                 LEAVE('i', 0);
 815                 return 0;
 816         }
 817
 818         while( rem > TCP_MAX_PACKET_SIZE )
 819         {
 820                 TCP_INT_SendDataPacket(conn, TCP_MAX_PACKET_SIZE, Buffer);
 821                 Buffer += TCP_MAX_PACKET_SIZE;
 822         }
 823
 824         TCP_INT_SendDataPacket(conn, rem, Buffer);
 825
 826         LEAVE('i', Length);
 827         return Length;
 828 }
 829
 830 /**
 831  * \brief Open a connection to another host using TCP
 832  * \param Conn  Connection structure
 833  */
 834 void TCP_StartConnection(tTCPConnection *Conn)
 835 {
 836         tTCPHeader      hdr = {0};
 837
 838         Conn->State = TCP_ST_SYN_SENT;
 839
 840         hdr.SourcePort = htons(Conn->LocalPort);
 841         hdr.DestPort = htons(Conn->RemotePort);
 842         Conn->NextSequenceSend = rand();
 843         hdr.SequenceNumber = htonl(Conn->NextSequenceSend);
 844         hdr.DataOffset = (sizeof(tTCPHeader)/4) << 4;
 845         hdr.Flags = TCP_FLAG_SYN;
 846         hdr.WindowSize = htons(TCP_WINDOW_SIZE);        // Max
 847         hdr.Checksum = 0;       // TODO
 848
 849         TCP_SendPacket( Conn, sizeof(tTCPHeader), &hdr );
 850
 851         Conn->NextSequenceSend ++;
 852         Conn->State = TCP_ST_SYN_SENT;
 853         return ;
 854 }
 855
 856 /**
 857  * \brief Control a client socket
 858  */
 859 int TCP_Client_IOCtl(tVFS_Node *Node, int ID, void *Data)
 860 {
 861         tTCPConnection  *conn = Node->ImplPtr;
 862
 863         switch(ID)
 864         {
 865         case 4: // Get/Set local port
 866                 if(!Data)
 867                         return conn->LocalPort;
 868                 if(conn->State != TCP_ST_CLOSED)
 869                         return -1;
 870                 if(!CheckMem(Data, sizeof(Uint16)))
 871                         return -1;
 872
 873                 if(Threads_GetUID() != 0 && *(Uint16*)Data < 1024)
 874                         return -1;
 875
 876                 conn->LocalPort = *(Uint16*)Data;
 877                 return 0;
 878
 879         case 5: // Get/Set remote port
 880                 if(!Data)       return conn->RemotePort;
 881                 if(conn->State != TCP_ST_CLOSED)        return -1;
 882                 if(!CheckMem(Data, sizeof(Uint16)))     return -1;
 883                 conn->RemotePort = *(Uint16*)Data;
 884                 return conn->RemotePort;
 885
 886         case 6: // Set Remote IP
 887                 if( conn->State != TCP_ST_CLOSED )
 888                         return -1;
 889                 if( conn->Interface->Type == 4 )
 890                 {
 891                         if(!CheckMem(Data, sizeof(tIPv4)))      return -1;
 892                         conn->RemoteIP.v4 = *(tIPv4*)Data;
 893                 }
 894                 else if( conn->Interface->Type == 6 )
 895                 {
 896                         if(!CheckMem(Data, sizeof(tIPv6)))      return -1;
 897                         conn->RemoteIP.v6 = *(tIPv6*)Data;
 898                 }
 899                 return 0;
 900
 901         case 7: // Connect
 902                 if(conn->LocalPort == 0xFFFF)
 903                         conn->LocalPort = TCP_GetUnusedPort();
 904                 if(conn->RemotePort == -1)
 905                         return 0;
 906
 907                 TCP_StartConnection(conn);
 908                 return 1;
 909
 910         // Get recieve buffer length
 911         case 8:
 912                 return conn->RecievedBuffer->Length;
 913         }
 914
 915         return 0;
 916 }
 917
 918 void TCP_Client_Close(tVFS_Node *Node)
 919 {
 920         tTCPConnection  *conn = Node->ImplPtr;
 921         tTCPHeader      packet;
 922
 923         packet.SourcePort = htons(conn->LocalPort);
 924         packet.DestPort = htons(conn->RemotePort);
 925         packet.DataOffset = (sizeof(tTCPHeader)/4)*16;
 926         packet.WindowSize = TCP_WINDOW_SIZE;
 927
 928         packet.AcknowlegementNumber = 0;
 929         packet.SequenceNumber = htonl(conn->NextSequenceSend);
 930         packet.Flags = TCP_FLAG_FIN;
 931
 932         conn->State = TCP_ST_FIN_SENT;
 933
 934         TCP_SendPacket( conn, sizeof(tTCPHeader), &packet );
 935
 936         while( conn->State == TCP_ST_FIN_SENT ) Threads_Yield();
 937
 938         free(conn);
 939 }