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 = htons( 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", "TCP_GetPacket: SourcePort = %i, DestPort = %i",
 108                 ntohs(hdr->SourcePort), ntohs(hdr->DestPort));
 109 /*
 110         Log_Log("TCP", "TCP_GetPacket: SequenceNumber = 0x%x", ntohl(hdr->SequenceNumber));
 111         Log_Log("TCP", "TCP_GetPacket: AcknowlegementNumber = 0x%x", ntohl(hdr->AcknowlegementNumber));
 112         Log_Log("TCP", "TCP_GetPacket: DataOffset = %i", hdr->DataOffset >> 4);
 113         Log_Log("TCP", "TCP_GetPacket: Flags = {");
 114         Log_Log("TCP", "TCP_GetPacket:   CWR = %B, ECE = %B",
 115                 !!(hdr->Flags & TCP_FLAG_CWR), !!(hdr->Flags & TCP_FLAG_ECE));
 116         Log_Log("TCP", "TCP_GetPacket:   URG = %B, ACK = %B",
 117                 !!(hdr->Flags & TCP_FLAG_URG), !!(hdr->Flags & TCP_FLAG_ACK));
 118         Log_Log("TCP", "TCP_GetPacket:   PSH = %B, RST = %B",
 119                 !!(hdr->Flags & TCP_FLAG_PSH), !!(hdr->Flags & TCP_FLAG_RST));
 120         Log_Log("TCP", "TCP_GetPacket:   SYN = %B, FIN = %B",
 121                 !!(hdr->Flags & TCP_FLAG_SYN), !!(hdr->Flags & TCP_FLAG_FIN));
 122         Log_Log("TCP", "TCP_GetPacket: }");
 123         Log_Log("TCP", "TCP_GetPacket: WindowSize = %i", htons(hdr->WindowSize));
 124         Log_Log("TCP", "TCP_GetPacket: Checksum = 0x%x", htons(hdr->Checksum));
 125         Log_Log("TCP", "TCP_GetPacket: UrgentPointer = 0x%x", htons(hdr->UrgentPointer));
 126 */
 127         Log_Log("TCP", "TCP_GetPacket: 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", "TCP_GetPacket: 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", "TCP_GetPacket: 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", "TCP_GetPacket: 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", "TCP_GetPacket: 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", "TCP_GetPacket: 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", "TCP_GetPacket: 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", "TCP_GetPacket: 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         // Syncronise sequence values
 286         if(Header->Flags & TCP_FLAG_SYN) {
 287                 Connection->NextSequenceRcv = ntohl(Header->SequenceNumber) + 1;
 288         }
 289
 290         // Handle a server replying to our initial SYN
 291         if( Connection->State == TCP_ST_SYN_SENT )
 292         {
 293                 if( (Header->Flags & (TCP_FLAG_SYN|TCP_FLAG_ACK)) == (TCP_FLAG_SYN|TCP_FLAG_ACK) )
 294                 {
 295                         Header->DestPort = Header->SourcePort;
 296                         Header->SourcePort = htons(Connection->LocalPort);
 297                         Header->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 298                         Header->SequenceNumber = htonl(Connection->NextSequenceSend);
 299                         Header->WindowSize = htons(TCP_WINDOW_SIZE);
 300                         Header->Flags = TCP_FLAG_ACK;
 301                         Header->DataOffset = (sizeof(tTCPHeader)/4) << 4;
 302                         Log_Log("TCP", "ACKing SYN-ACK");
 303                         TCP_SendPacket( Connection, sizeof(tTCPHeader), Header );
 304                         Connection->State = TCP_ST_OPEN;
 305                 }
 306         }
 307
 308         // Handle a client confirming the connection
 309         if( Connection->State == TCP_ST_HALFOPEN && (Header->Flags & TCP_FLAG_ACK) )
 310         {
 311                 Connection->State = TCP_ST_OPEN;
 312                 Log_Log("TCP", "Connection fully opened");
 313         }
 314
 315         // Get length of data
 316         dataLen = Length - (Header->DataOffset>>4)*4;
 317         Log_Log("TCP", "HandleConnectionPacket - dataLen = %i", dataLen);
 318
 319         if(Header->Flags & TCP_FLAG_ACK) {
 320                 // TODO: Process an ACKed Packet
 321                 Log_Log("TCP", "Conn %p, Packet 0x%x ACKed", Connection, Header->AcknowlegementNumber);
 322         }
 323
 324         // TODO: Check what to do here
 325         if(Header->Flags & TCP_FLAG_FIN) {
 326                 if( Connection->State == TCP_ST_FIN_SENT ) {
 327                         Connection->State = TCP_ST_FINISHED;
 328                         return ;
 329                 }
 330                 else {
 331                         Connection->State = TCP_ST_FINISHED;
 332                         Header->DestPort = Header->SourcePort;
 333                         Header->SourcePort = htons(Connection->LocalPort);
 334                         Header->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 335                         Header->SequenceNumber = htonl(Connection->NextSequenceSend);
 336                         Header->Flags = TCP_FLAG_ACK;
 337                         TCP_SendPacket( Connection, sizeof(tTCPHeader), Header );
 338                         return ;
 339                 }
 340         }
 341
 342         // Check for an empty packet
 343         if(dataLen == 0) {
 344                 Log_Log("TCP", "Empty Packet");
 345                 return ;
 346         }
 347
 348         // NOTES:
 349         // Flags
 350         //    PSH - Has Data?
 351         // /NOTES
 352
 353         // Allocate and fill cached packet
 354         pkt = malloc( dataLen + sizeof(tTCPStoredPacket) );
 355         pkt->Next = NULL;
 356         pkt->Sequence = ntohl(Header->SequenceNumber);
 357         pkt->Length = dataLen;
 358         memcpy(pkt->Data, (Uint8*)Header + (Header->DataOffset>>4)*4, dataLen);
 359
 360         // Is this packet the next expected packet?
 361         // TODO: Fix this to check if the packet is in the window.
 362         if( pkt->Sequence != Connection->NextSequenceRcv )
 363         {
 364                 tTCPStoredPacket        *tmp, *prev = NULL;
 365
 366                 Log_Log("TCP", "Out of sequence packet (0x%08x != 0x%08x)",
 367                         pkt->Sequence, Connection->NextSequenceRcv);
 368
 369                 // No? Well, let's cache it and look at it later
 370                 SHORTLOCK( &Connection->lFuturePackets );
 371                 for(tmp = Connection->FuturePackets;
 372                         tmp;
 373                         prev = tmp, tmp = tmp->Next)
 374                 {
 375                         if(tmp->Sequence > pkt->Sequence)       break;
 376                 }
 377                 if(prev)
 378                         prev->Next = pkt;
 379                 else
 380                         Connection->FuturePackets = pkt;
 381                 pkt->Next = tmp;
 382                 SHORTREL( &Connection->lFuturePackets );
 383         }
 384         else
 385         {
 386                 // Ooh, Goodie! Add it to the recieved list
 387                 TCP_INT_AppendRecieved(Connection, pkt);
 388                 free(pkt);
 389                 Log_Log("TCP", "0x%08x += %i", Connection->NextSequenceRcv, dataLen);
 390                 Connection->NextSequenceRcv += dataLen;
 391
 392                 // TODO: This should be moved out of the watcher thread,
 393                 // so that a single lost packet on one connection doesn't cause
 394                 // all connections on the interface to lag.
 395                 TCP_INT_UpdateRecievedFromFuture(Connection);
 396
 397                 // ACK Packet
 398                 Header->DestPort = Header->SourcePort;
 399                 Header->SourcePort = htons(Connection->LocalPort);
 400                 Header->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 401                 Header->SequenceNumber = htonl(Connection->NextSequenceSend);
 402                 Header->WindowSize = htons(TCP_WINDOW_SIZE);
 403                 Header->Flags &= TCP_FLAG_SYN;  // Eliminate all flags save for SYN
 404                 Header->Flags |= TCP_FLAG_ACK;  // Add ACK
 405                 Log_Log("TCP", "Sending ACK for 0x%08x", Connection->NextSequenceRcv);
 406                 TCP_SendPacket( Connection, sizeof(tTCPHeader), Header );
 407                 //Connection->NextSequenceSend ++;
 408         }
 409 }
 410
 411 /**
 412  * \brief Appends a packet to the recieved list
 413  * \param Connection    Connection structure
 414  * \param Pkt   Packet structure on heap
 415  */
 416 void TCP_INT_AppendRecieved(tTCPConnection *Connection, tTCPStoredPacket *Pkt)
 417 {
 418         Mutex_Acquire( &Connection->lRecievedPackets );
 419         if(Connection->RecievedBuffer->Length + Pkt->Length > Connection->RecievedBuffer->Space )
 420         {
 421                 Log_Error("TCP", "Buffer filled, packet dropped (%s)",
 422                 //      TCP_INT_DumpConnection(Connection)
 423                         ""
 424                         );
 425                 return ;
 426         }
 427
 428         RingBuffer_Write( Connection->RecievedBuffer, Pkt->Data, Pkt->Length );
 429
 430         Mutex_Release( &Connection->lRecievedPackets );
 431 }
 432
 433 /**
 434  * \brief Updates the connections recieved list from the future list
 435  * \param Connection    Connection structure
 436  *
 437  * Updates the recieved packets list with packets from the future (out
 438  * of order) packets list that are now able to be added in direct
 439  * sequence.
 440  */
 441 void TCP_INT_UpdateRecievedFromFuture(tTCPConnection *Connection)
 442 {
 443         tTCPStoredPacket        *pkt, *prev;
 444         for(;;)
 445         {
 446                 prev = NULL;
 447                 // Look for the next expected packet in the cache.
 448                 SHORTLOCK( &Connection->lFuturePackets );
 449                 for(pkt = Connection->FuturePackets;
 450                         pkt && pkt->Sequence < Connection->NextSequenceRcv;
 451                         prev = pkt, pkt = pkt->Next);
 452
 453                 // If we can't find the expected next packet, stop looking
 454                 if(!pkt || pkt->Sequence > Connection->NextSequenceRcv) {
 455                         SHORTREL( &Connection->lFuturePackets );
 456                         return;
 457                 }
 458
 459                 // Delete packet from future list
 460                 if(prev)
 461                         prev->Next = pkt->Next;
 462                 else
 463                         Connection->FuturePackets = pkt->Next;
 464
 465                 // Release list
 466                 SHORTREL( &Connection->lFuturePackets );
 467
 468                 // Looks like we found one
 469                 TCP_INT_AppendRecieved(Connection, pkt);
 470                 Connection->NextSequenceRcv += pkt->Length;
 471                 free(pkt);
 472         }
 473 }
 474
 475 /**
 476  * \fn Uint16 TCP_GetUnusedPort()
 477  * \brief Gets an unused port and allocates it
 478  */
 479 Uint16 TCP_GetUnusedPort()
 480 {
 481         Uint16  ret;
 482
 483         // Get Next outbound port
 484         ret = giTCP_NextOutPort++;
 485         while( gaTCP_PortBitmap[ret/32] & (1 << (ret%32)) )
 486         {
 487                 ret ++;
 488                 giTCP_NextOutPort++;
 489                 if(giTCP_NextOutPort == 0x10000) {
 490                         ret = giTCP_NextOutPort = TCP_MIN_DYNPORT;
 491                 }
 492         }
 493
 494         // Mark the new port as used
 495         gaTCP_PortBitmap[ret/32] |= 1 << (ret%32);
 496
 497         return ret;
 498 }
 499
 500 /**
 501  * \fn int TCP_AllocatePort(Uint16 Port)
 502  * \brief Marks a port as used
 503  */
 504 int TCP_AllocatePort(Uint16 Port)
 505 {
 506         // Check if the port has already been allocated
 507         if( gaTCP_PortBitmap[Port/32] & (1 << (Port%32)) )
 508                 return 0;
 509
 510         // Allocate
 511         gaTCP_PortBitmap[Port/32] |= 1 << (Port%32);
 512
 513         return 1;
 514 }
 515
 516 /**
 517  * \fn int TCP_DeallocatePort(Uint16 Port)
 518  * \brief Marks a port as unused
 519  */
 520 int TCP_DeallocatePort(Uint16 Port)
 521 {
 522         // Check if the port has already been allocated
 523         if( !(gaTCP_PortBitmap[Port/32] & (1 << (Port%32))) )
 524                 return 0;
 525
 526         // Allocate
 527         gaTCP_PortBitmap[Port/32] &= ~(1 << (Port%32));
 528
 529         return 1;
 530 }
 531
 532 // --- Server
 533 tVFS_Node *TCP_Server_Init(tInterface *Interface)
 534 {
 535         tTCPListener    *srv;
 536
 537         srv = malloc( sizeof(tTCPListener) );
 538
 539         if( srv == NULL ) {
 540                 Log_Warning("TCP", "malloc failed for listener (%i) bytes", sizeof(tTCPListener));
 541                 return NULL;
 542         }
 543
 544         srv->Interface = Interface;
 545         srv->Port = 0;
 546         srv->NextID = 0;
 547         srv->Connections = NULL;
 548         srv->ConnectionsTail = NULL;
 549         srv->NewConnections = NULL;
 550         srv->Next = NULL;
 551         srv->Node.Flags = VFS_FFLAG_DIRECTORY;
 552         srv->Node.Size = -1;
 553         srv->Node.ImplPtr = srv;
 554         srv->Node.NumACLs = 1;
 555         srv->Node.ACLs = &gVFS_ACL_EveryoneRW;
 556         srv->Node.ReadDir = TCP_Server_ReadDir;
 557         srv->Node.FindDir = TCP_Server_FindDir;
 558         srv->Node.IOCtl = TCP_Server_IOCtl;
 559         srv->Node.Close = TCP_Server_Close;
 560
 561         SHORTLOCK(&glTCP_Listeners);
 562         srv->Next = gTCP_Listeners;
 563         gTCP_Listeners = srv;
 564         SHORTREL(&glTCP_Listeners);
 565
 566         return &srv->Node;
 567 }
 568
 569 /**
 570  * \brief Wait for a new connection and return the connection ID
 571  * \note Blocks until a new connection is made
 572  * \param Node  Server node
 573  * \param Pos   Position (ignored)
 574  */
 575 char *TCP_Server_ReadDir(tVFS_Node *Node, int Pos)
 576 {
 577         tTCPListener    *srv = Node->ImplPtr;
 578         tTCPConnection  *conn;
 579         char    *ret;
 580
 581         ENTER("pNode iPos", Node, Pos);
 582
 583         Log_Log("TCP", "Thread %i waiting for a connection", Threads_GetTID());
 584         for(;;)
 585         {
 586                 SHORTLOCK( &srv->lConnections );
 587                 if( srv->NewConnections != NULL )       break;
 588                 SHORTREL( &srv->lConnections );
 589                 Threads_Yield();        // TODO: Sleep until poked
 590                 continue;
 591         }
 592
 593
 594         // Increment the new list (the current connection is still on the
 595         // normal list)
 596         conn = srv->NewConnections;
 597         srv->NewConnections = conn->Next;
 598
 599         SHORTREL( &srv->lConnections );
 600
 601         LOG("conn = %p", conn);
 602         LOG("srv->Connections = %p", srv->Connections);
 603         LOG("srv->NewConnections = %p", srv->NewConnections);
 604         LOG("srv->ConnectionsTail = %p", srv->ConnectionsTail);
 605
 606         ret = malloc(9);
 607         itoa(ret, conn->Node.ImplInt, 16, 8, '0');
 608         Log_Log("TCP", "Thread %i got '%s'", Threads_GetTID(), ret);
 609         LEAVE('s', ret);
 610         return ret;
 611 }
 612
 613 /**
 614  * \brief Gets a client connection node
 615  * \param Node  Server node
 616  * \param Name  Hexadecimal ID of the node
 617  */
 618 tVFS_Node *TCP_Server_FindDir(tVFS_Node *Node, const char *Name)
 619 {
 620         tTCPConnection  *conn;
 621         tTCPListener    *srv = Node->ImplPtr;
 622         char    tmp[9];
 623          int    id = atoi(Name);
 624
 625         ENTER("pNode sName", Node, Name);
 626
 627         // Sanity Check
 628         itoa(tmp, id, 16, 8, '0');
 629         if(strcmp(tmp, Name) != 0) {
 630                 LOG("'%s' != '%s' (%08x)", Name, tmp, id);
 631                 LEAVE('n');
 632                 return NULL;
 633         }
 634
 635         Log_Debug("TCP", "srv->Connections = %p", srv->Connections);
 636         Log_Debug("TCP", "srv->NewConnections = %p", srv->NewConnections);
 637         Log_Debug("TCP", "srv->ConnectionsTail = %p", srv->ConnectionsTail);
 638
 639         // Search
 640         SHORTLOCK( &srv->lConnections );
 641         for(conn = srv->Connections;
 642                 conn;
 643                 conn = conn->Next)
 644         {
 645                 LOG("conn->Node.ImplInt = %i", conn->Node.ImplInt);
 646                 if(conn->Node.ImplInt == id)    break;
 647         }
 648         SHORTREL( &srv->lConnections );
 649
 650         // If not found, ret NULL
 651         if(!conn) {
 652                 LOG("Connection %i not found", id);
 653                 LEAVE('n');
 654                 return NULL;
 655         }
 656
 657         // Return node
 658         LEAVE('p', &conn->Node);
 659         return &conn->Node;
 660 }
 661
 662 /**
 663  * \brief Handle IOCtl calls
 664  */
 665 int TCP_Server_IOCtl(tVFS_Node *Node, int ID, void *Data)
 666 {
 667         tTCPListener    *srv = Node->ImplPtr;
 668
 669         switch(ID)
 670         {
 671         case 4: // Get/Set Port
 672                 if(!Data)       // Get Port
 673                         return srv->Port;
 674
 675                 if(srv->Port)   // Wait, you can't CHANGE the port
 676                         return -1;
 677
 678                 if(!CheckMem(Data, sizeof(Uint16)))     // Sanity check
 679                         return -1;
 680
 681                 // Permissions check
 682                 if(Threads_GetUID() != 0
 683                 && *(Uint16*)Data != 0
 684                 && *(Uint16*)Data < 1024)
 685                         return -1;
 686
 687                 // TODO: Check if a port is in use
 688
 689                 // Set Port
 690                 srv->Port = *(Uint16*)Data;
 691                 if(srv->Port == 0)      // Allocate a random port
 692                         srv->Port = TCP_GetUnusedPort();
 693                 else    // Else, mark this as used
 694                         TCP_AllocatePort(srv->Port);
 695
 696                 Log_Log("TCP", "Server %p listening on port %i", srv, srv->Port);
 697
 698                 return srv->Port;
 699         }
 700         return 0;
 701 }
 702
 703 void TCP_Server_Close(tVFS_Node *Node)
 704 {
 705         free(Node->ImplPtr);
 706 }
 707
 708 // --- Client
 709 /**
 710  * \brief Create a client node
 711  */
 712 tVFS_Node *TCP_Client_Init(tInterface *Interface)
 713 {
 714         tTCPConnection  *conn = malloc( sizeof(tTCPConnection) );
 715
 716         conn->State = TCP_ST_CLOSED;
 717         conn->Interface = Interface;
 718         conn->LocalPort = -1;
 719         conn->RemotePort = -1;
 720         memset( &conn->RemoteIP, 0, sizeof(conn->RemoteIP) );
 721
 722         conn->Node.ImplPtr = conn;
 723         conn->Node.NumACLs = 1;
 724         conn->Node.ACLs = &gVFS_ACL_EveryoneRW;
 725         conn->Node.Read = TCP_Client_Read;
 726         conn->Node.Write = TCP_Client_Write;
 727         conn->Node.IOCtl = TCP_Client_IOCtl;
 728         conn->Node.Close = TCP_Client_Close;
 729
 730         conn->RecievedBuffer = RingBuffer_Create( TCP_RECIEVE_BUFFER_SIZE );
 731
 732         SHORTLOCK(&glTCP_OutbountCons);
 733         conn->Next = gTCP_OutbountCons;
 734         gTCP_OutbountCons = conn;
 735         SHORTREL(&glTCP_OutbountCons);
 736
 737         return &conn->Node;
 738 }
 739
 740 /**
 741  * \brief Wait for a packet and return it
 742  * \note If \a Length is smaller than the size of the packet, the rest
 743  *       of the packet's data will be discarded.
 744  */
 745 Uint64 TCP_Client_Read(tVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer)
 746 {
 747         tTCPConnection  *conn = Node->ImplPtr;
 748         char    *destbuf = Buffer;
 749         size_t  len;
 750
 751         ENTER("pNode XOffset XLength pBuffer", Node, Offset, Length, Buffer);
 752         LOG("conn = %p", conn);
 753         LOG("conn->State = %i", conn->State);
 754
 755         // Check if connection is open
 756         while( conn->State == TCP_ST_HALFOPEN || conn->State == TCP_ST_SYN_SENT )
 757                 Threads_Yield();
 758         if( conn->State != TCP_ST_OPEN ) {
 759                 LEAVE('i', 0);
 760                 return 0;
 761         }
 762
 763         // Poll packets
 764         for(;;)
 765         {
 766                 // Lock list and check if there is a packet
 767                 Mutex_Acquire( &conn->lRecievedPackets );
 768                 if( conn->RecievedBuffer->Length == 0 ) {
 769                         // If not, release the lock, yield and try again
 770                         Mutex_Release( &conn->lRecievedPackets );
 771                         Threads_Yield();        // TODO: Less expensive wait
 772                         continue;
 773                 }
 774
 775                 // Attempt to read all `Length` bytes
 776                 len = RingBuffer_Read( destbuf, conn->RecievedBuffer, Length );
 777
 778                 // Release the lock (we don't need it any more)
 779                 Mutex_Release( &conn->lRecievedPackets );
 780
 781                 LEAVE('i', len);
 782                 return len;
 783         }
 784 }
 785
 786 /**
 787  * \brief Send a data packet on a connection
 788  */
 789 void TCP_INT_SendDataPacket(tTCPConnection *Connection, size_t Length, void *Data)
 790 {
 791         char    buf[sizeof(tTCPHeader)+Length];
 792         tTCPHeader      *packet = (void*)buf;
 793
 794         packet->SourcePort = htons(Connection->LocalPort);
 795         packet->DestPort = htons(Connection->RemotePort);
 796         packet->DataOffset = (sizeof(tTCPHeader)/4)*16;
 797         packet->WindowSize = TCP_WINDOW_SIZE;
 798
 799         packet->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 800         packet->SequenceNumber = htonl(Connection->NextSequenceSend);
 801         packet->Flags = TCP_FLAG_PSH|TCP_FLAG_ACK;      // Hey, ACK if you can!
 802
 803         memcpy(packet->Options, Data, Length);
 804
 805         TCP_SendPacket( Connection, sizeof(tTCPHeader)+Length, packet );
 806
 807         Connection->NextSequenceSend += Length;
 808 }
 809
 810 /**
 811  * \brief Send some bytes on a connection
 812  */
 813 Uint64 TCP_Client_Write(tVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer)
 814 {
 815         tTCPConnection  *conn = Node->ImplPtr;
 816         size_t  rem = Length;
 817
 818         ENTER("pNode XOffset XLength pBuffer", Node, Offset, Length, Buffer);
 819
 820         // Check if connection is open
 821         while( conn->State == TCP_ST_HALFOPEN || conn->State == TCP_ST_SYN_SENT )
 822                 Threads_Yield();
 823         if( conn->State != TCP_ST_OPEN ) {
 824                 LEAVE('i', 0);
 825                 return 0;
 826         }
 827
 828         while( rem > TCP_MAX_PACKET_SIZE )
 829         {
 830                 TCP_INT_SendDataPacket(conn, TCP_MAX_PACKET_SIZE, Buffer);
 831                 Buffer += TCP_MAX_PACKET_SIZE;
 832         }
 833
 834         TCP_INT_SendDataPacket(conn, rem, Buffer);
 835
 836         LEAVE('i', Length);
 837         return Length;
 838 }
 839
 840 /**
 841  * \brief Open a connection to another host using TCP
 842  * \param Conn  Connection structure
 843  */
 844 void TCP_StartConnection(tTCPConnection *Conn)
 845 {
 846         tTCPHeader      hdr = {0};
 847
 848         Conn->State = TCP_ST_SYN_SENT;
 849
 850         hdr.SourcePort = htons(Conn->LocalPort);
 851         hdr.DestPort = htons(Conn->RemotePort);
 852         Conn->NextSequenceSend = rand();
 853         hdr.SequenceNumber = htonl(Conn->NextSequenceSend);
 854         hdr.DataOffset = (sizeof(tTCPHeader)/4) << 4;
 855         hdr.Flags = TCP_FLAG_SYN;
 856         hdr.WindowSize = htons(TCP_WINDOW_SIZE);        // Max
 857         hdr.Checksum = 0;       // TODO
 858
 859         TCP_SendPacket( Conn, sizeof(tTCPHeader), &hdr );
 860
 861         Conn->NextSequenceSend ++;
 862         Conn->State = TCP_ST_SYN_SENT;
 863         return ;
 864 }
 865
 866 /**
 867  * \brief Control a client socket
 868  */
 869 int TCP_Client_IOCtl(tVFS_Node *Node, int ID, void *Data)
 870 {
 871         tTCPConnection  *conn = Node->ImplPtr;
 872
 873         ENTER("pNode iID pData", Node, ID, Data);
 874
 875         switch(ID)
 876         {
 877         case 4: // Get/Set local port
 878                 if(!Data)
 879                         LEAVE_RET('i', conn->LocalPort);
 880                 if(conn->State != TCP_ST_CLOSED)
 881                         LEAVE_RET('i', -1);
 882                 if(!CheckMem(Data, sizeof(Uint16)))
 883                         LEAVE_RET('i', -1);
 884
 885                 if(Threads_GetUID() != 0 && *(Uint16*)Data < 1024)
 886                         LEAVE_RET('i', -1);
 887
 888                 conn->LocalPort = *(Uint16*)Data;
 889                 LEAVE_RET('i', conn->LocalPort);
 890
 891         case 5: // Get/Set remote port
 892                 if(!Data)       LEAVE_RET('i', conn->RemotePort);
 893                 if(conn->State != TCP_ST_CLOSED)        LEAVE_RET('i', -1);
 894                 if(!CheckMem(Data, sizeof(Uint16)))     LEAVE_RET('i', -1);
 895                 conn->RemotePort = *(Uint16*)Data;
 896                 LEAVE_RET('i', conn->RemotePort);
 897
 898         case 6: // Set Remote IP
 899                 if( conn->State != TCP_ST_CLOSED )
 900                         LEAVE_RET('i', -1);
 901                 if( conn->Interface->Type == 4 )
 902                 {
 903                         if(!CheckMem(Data, sizeof(tIPv4)))      LEAVE_RET('i', -1);
 904                         conn->RemoteIP.v4 = *(tIPv4*)Data;
 905                 }
 906                 else if( conn->Interface->Type == 6 )
 907                 {
 908                         if(!CheckMem(Data, sizeof(tIPv6)))      LEAVE_RET('i', -1);
 909                         conn->RemoteIP.v6 = *(tIPv6*)Data;
 910                 }
 911                 LEAVE_RET('i', 0);
 912
 913         case 7: // Connect
 914                 if(conn->LocalPort == 0xFFFF)
 915                         conn->LocalPort = TCP_GetUnusedPort();
 916                 if(conn->RemotePort == -1)
 917                         LEAVE_RET('i', 0);
 918
 919                 TCP_StartConnection(conn);
 920                 LEAVE_RET('i', 1);
 921
 922         // Get recieve buffer length
 923         case 8:
 924                 LEAVE_RET('i', conn->RecievedBuffer->Length);
 925         }
 926
 927         return 0;
 928 }
 929
 930 void TCP_Client_Close(tVFS_Node *Node)
 931 {
 932         tTCPConnection  *conn = Node->ImplPtr;
 933         tTCPHeader      packet;
 934
 935         ENTER("pNode", Node);
 936
 937         packet.SourcePort = htons(conn->LocalPort);
 938         packet.DestPort = htons(conn->RemotePort);
 939         packet.DataOffset = (sizeof(tTCPHeader)/4)*16;
 940         packet.WindowSize = TCP_WINDOW_SIZE;
 941
 942         packet.AcknowlegementNumber = 0;
 943         packet.SequenceNumber = htonl(conn->NextSequenceSend);
 944         packet.Flags = TCP_FLAG_FIN;
 945
 946         conn->State = TCP_ST_FIN_SENT;
 947
 948         TCP_SendPacket( conn, sizeof(tTCPHeader), &packet );
 949
 950         while( conn->State == TCP_ST_FIN_SENT ) Threads_Yield();
 951
 952         free(conn);
 953
 954         LEAVE('-');
 955 }