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         #if USE_SELECT
 431         VFS_MarkAvaliable(&Connection->Node, 1);
 432         #endif
 433
 434         Mutex_Release( &Connection->lRecievedPackets );
 435 }
 436
 437 /**
 438  * \brief Updates the connections recieved list from the future list
 439  * \param Connection    Connection structure
 440  *
 441  * Updates the recieved packets list with packets from the future (out
 442  * of order) packets list that are now able to be added in direct
 443  * sequence.
 444  */
 445 void TCP_INT_UpdateRecievedFromFuture(tTCPConnection *Connection)
 446 {
 447         tTCPStoredPacket        *pkt, *prev;
 448         for(;;)
 449         {
 450                 prev = NULL;
 451                 // Look for the next expected packet in the cache.
 452                 SHORTLOCK( &Connection->lFuturePackets );
 453                 for(pkt = Connection->FuturePackets;
 454                         pkt && pkt->Sequence < Connection->NextSequenceRcv;
 455                         prev = pkt, pkt = pkt->Next);
 456
 457                 // If we can't find the expected next packet, stop looking
 458                 if(!pkt || pkt->Sequence > Connection->NextSequenceRcv) {
 459                         SHORTREL( &Connection->lFuturePackets );
 460                         return;
 461                 }
 462
 463                 // Delete packet from future list
 464                 if(prev)
 465                         prev->Next = pkt->Next;
 466                 else
 467                         Connection->FuturePackets = pkt->Next;
 468
 469                 // Release list
 470                 SHORTREL( &Connection->lFuturePackets );
 471
 472                 // Looks like we found one
 473                 TCP_INT_AppendRecieved(Connection, pkt);
 474                 Connection->NextSequenceRcv += pkt->Length;
 475                 free(pkt);
 476         }
 477 }
 478
 479 /**
 480  * \fn Uint16 TCP_GetUnusedPort()
 481  * \brief Gets an unused port and allocates it
 482  */
 483 Uint16 TCP_GetUnusedPort()
 484 {
 485         Uint16  ret;
 486
 487         // Get Next outbound port
 488         ret = giTCP_NextOutPort++;
 489         while( gaTCP_PortBitmap[ret/32] & (1 << (ret%32)) )
 490         {
 491                 ret ++;
 492                 giTCP_NextOutPort++;
 493                 if(giTCP_NextOutPort == 0x10000) {
 494                         ret = giTCP_NextOutPort = TCP_MIN_DYNPORT;
 495                 }
 496         }
 497
 498         // Mark the new port as used
 499         gaTCP_PortBitmap[ret/32] |= 1 << (ret%32);
 500
 501         return ret;
 502 }
 503
 504 /**
 505  * \fn int TCP_AllocatePort(Uint16 Port)
 506  * \brief Marks a port as used
 507  */
 508 int TCP_AllocatePort(Uint16 Port)
 509 {
 510         // Check if the port has already been allocated
 511         if( gaTCP_PortBitmap[Port/32] & (1 << (Port%32)) )
 512                 return 0;
 513
 514         // Allocate
 515         gaTCP_PortBitmap[Port/32] |= 1 << (Port%32);
 516
 517         return 1;
 518 }
 519
 520 /**
 521  * \fn int TCP_DeallocatePort(Uint16 Port)
 522  * \brief Marks a port as unused
 523  */
 524 int TCP_DeallocatePort(Uint16 Port)
 525 {
 526         // Check if the port has already been allocated
 527         if( !(gaTCP_PortBitmap[Port/32] & (1 << (Port%32))) )
 528                 return 0;
 529
 530         // Allocate
 531         gaTCP_PortBitmap[Port/32] &= ~(1 << (Port%32));
 532
 533         return 1;
 534 }
 535
 536 // --- Server
 537 tVFS_Node *TCP_Server_Init(tInterface *Interface)
 538 {
 539         tTCPListener    *srv;
 540
 541         srv = malloc( sizeof(tTCPListener) );
 542
 543         if( srv == NULL ) {
 544                 Log_Warning("TCP", "malloc failed for listener (%i) bytes", sizeof(tTCPListener));
 545                 return NULL;
 546         }
 547
 548         srv->Interface = Interface;
 549         srv->Port = 0;
 550         srv->NextID = 0;
 551         srv->Connections = NULL;
 552         srv->ConnectionsTail = NULL;
 553         srv->NewConnections = NULL;
 554         srv->Next = NULL;
 555         srv->Node.Flags = VFS_FFLAG_DIRECTORY;
 556         srv->Node.Size = -1;
 557         srv->Node.ImplPtr = srv;
 558         srv->Node.NumACLs = 1;
 559         srv->Node.ACLs = &gVFS_ACL_EveryoneRW;
 560         srv->Node.ReadDir = TCP_Server_ReadDir;
 561         srv->Node.FindDir = TCP_Server_FindDir;
 562         srv->Node.IOCtl = TCP_Server_IOCtl;
 563         srv->Node.Close = TCP_Server_Close;
 564
 565         SHORTLOCK(&glTCP_Listeners);
 566         srv->Next = gTCP_Listeners;
 567         gTCP_Listeners = srv;
 568         SHORTREL(&glTCP_Listeners);
 569
 570         return &srv->Node;
 571 }
 572
 573 /**
 574  * \brief Wait for a new connection and return the connection ID
 575  * \note Blocks until a new connection is made
 576  * \param Node  Server node
 577  * \param Pos   Position (ignored)
 578  */
 579 char *TCP_Server_ReadDir(tVFS_Node *Node, int Pos)
 580 {
 581         tTCPListener    *srv = Node->ImplPtr;
 582         tTCPConnection  *conn;
 583         char    *ret;
 584
 585         ENTER("pNode iPos", Node, Pos);
 586
 587         Log_Log("TCP", "Thread %i waiting for a connection", Threads_GetTID());
 588         for(;;)
 589         {
 590                 SHORTLOCK( &srv->lConnections );
 591                 if( srv->NewConnections != NULL )       break;
 592                 SHORTREL( &srv->lConnections );
 593                 Threads_Yield();        // TODO: Sleep until poked
 594                 continue;
 595         }
 596
 597
 598         // Increment the new list (the current connection is still on the
 599         // normal list)
 600         conn = srv->NewConnections;
 601         srv->NewConnections = conn->Next;
 602
 603         SHORTREL( &srv->lConnections );
 604
 605         LOG("conn = %p", conn);
 606         LOG("srv->Connections = %p", srv->Connections);
 607         LOG("srv->NewConnections = %p", srv->NewConnections);
 608         LOG("srv->ConnectionsTail = %p", srv->ConnectionsTail);
 609
 610         ret = malloc(9);
 611         itoa(ret, conn->Node.ImplInt, 16, 8, '0');
 612         Log_Log("TCP", "Thread %i got '%s'", Threads_GetTID(), ret);
 613         LEAVE('s', ret);
 614         return ret;
 615 }
 616
 617 /**
 618  * \brief Gets a client connection node
 619  * \param Node  Server node
 620  * \param Name  Hexadecimal ID of the node
 621  */
 622 tVFS_Node *TCP_Server_FindDir(tVFS_Node *Node, const char *Name)
 623 {
 624         tTCPConnection  *conn;
 625         tTCPListener    *srv = Node->ImplPtr;
 626         char    tmp[9];
 627          int    id = atoi(Name);
 628
 629         ENTER("pNode sName", Node, Name);
 630
 631         // Sanity Check
 632         itoa(tmp, id, 16, 8, '0');
 633         if(strcmp(tmp, Name) != 0) {
 634                 LOG("'%s' != '%s' (%08x)", Name, tmp, id);
 635                 LEAVE('n');
 636                 return NULL;
 637         }
 638
 639         Log_Debug("TCP", "srv->Connections = %p", srv->Connections);
 640         Log_Debug("TCP", "srv->NewConnections = %p", srv->NewConnections);
 641         Log_Debug("TCP", "srv->ConnectionsTail = %p", srv->ConnectionsTail);
 642
 643         // Search
 644         SHORTLOCK( &srv->lConnections );
 645         for(conn = srv->Connections;
 646                 conn;
 647                 conn = conn->Next)
 648         {
 649                 LOG("conn->Node.ImplInt = %i", conn->Node.ImplInt);
 650                 if(conn->Node.ImplInt == id)    break;
 651         }
 652         SHORTREL( &srv->lConnections );
 653
 654         // If not found, ret NULL
 655         if(!conn) {
 656                 LOG("Connection %i not found", id);
 657                 LEAVE('n');
 658                 return NULL;
 659         }
 660
 661         // Return node
 662         LEAVE('p', &conn->Node);
 663         return &conn->Node;
 664 }
 665
 666 /**
 667  * \brief Handle IOCtl calls
 668  */
 669 int TCP_Server_IOCtl(tVFS_Node *Node, int ID, void *Data)
 670 {
 671         tTCPListener    *srv = Node->ImplPtr;
 672
 673         switch(ID)
 674         {
 675         case 4: // Get/Set Port
 676                 if(!Data)       // Get Port
 677                         return srv->Port;
 678
 679                 if(srv->Port)   // Wait, you can't CHANGE the port
 680                         return -1;
 681
 682                 if(!CheckMem(Data, sizeof(Uint16)))     // Sanity check
 683                         return -1;
 684
 685                 // Permissions check
 686                 if(Threads_GetUID() != 0
 687                 && *(Uint16*)Data != 0
 688                 && *(Uint16*)Data < 1024)
 689                         return -1;
 690
 691                 // TODO: Check if a port is in use
 692
 693                 // Set Port
 694                 srv->Port = *(Uint16*)Data;
 695                 if(srv->Port == 0)      // Allocate a random port
 696                         srv->Port = TCP_GetUnusedPort();
 697                 else    // Else, mark this as used
 698                         TCP_AllocatePort(srv->Port);
 699
 700                 Log_Log("TCP", "Server %p listening on port %i", srv, srv->Port);
 701
 702                 return srv->Port;
 703         }
 704         return 0;
 705 }
 706
 707 void TCP_Server_Close(tVFS_Node *Node)
 708 {
 709         free(Node->ImplPtr);
 710 }
 711
 712 // --- Client
 713 /**
 714  * \brief Create a client node
 715  */
 716 tVFS_Node *TCP_Client_Init(tInterface *Interface)
 717 {
 718         tTCPConnection  *conn = malloc( sizeof(tTCPConnection) );
 719
 720         conn->State = TCP_ST_CLOSED;
 721         conn->Interface = Interface;
 722         conn->LocalPort = -1;
 723         conn->RemotePort = -1;
 724         memset( &conn->RemoteIP, 0, sizeof(conn->RemoteIP) );
 725
 726         conn->Node.ImplPtr = conn;
 727         conn->Node.NumACLs = 1;
 728         conn->Node.ACLs = &gVFS_ACL_EveryoneRW;
 729         conn->Node.Read = TCP_Client_Read;
 730         conn->Node.Write = TCP_Client_Write;
 731         conn->Node.IOCtl = TCP_Client_IOCtl;
 732         conn->Node.Close = TCP_Client_Close;
 733
 734         conn->RecievedBuffer = RingBuffer_Create( TCP_RECIEVE_BUFFER_SIZE );
 735
 736         SHORTLOCK(&glTCP_OutbountCons);
 737         conn->Next = gTCP_OutbountCons;
 738         gTCP_OutbountCons = conn;
 739         SHORTREL(&glTCP_OutbountCons);
 740
 741         return &conn->Node;
 742 }
 743
 744 /**
 745  * \brief Wait for a packet and return it
 746  * \note If \a Length is smaller than the size of the packet, the rest
 747  *       of the packet's data will be discarded.
 748  */
 749 Uint64 TCP_Client_Read(tVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer)
 750 {
 751         tTCPConnection  *conn = Node->ImplPtr;
 752         char    *destbuf = Buffer;
 753         size_t  len;
 754
 755         ENTER("pNode XOffset XLength pBuffer", Node, Offset, Length, Buffer);
 756         LOG("conn = %p", conn);
 757         LOG("conn->State = %i", conn->State);
 758
 759         // Check if connection is open
 760         while( conn->State == TCP_ST_HALFOPEN || conn->State == TCP_ST_SYN_SENT )
 761                 Threads_Yield();
 762         if( conn->State != TCP_ST_OPEN ) {
 763                 LEAVE('i', 0);
 764                 return 0;
 765         }
 766
 767         // Poll packets
 768         for(;;)
 769         {
 770                 #if USE_SELECT
 771                 // Wait
 772                 VFS_SelectNode(Node, VFS_SELECT_READ, NULL);
 773                 // Lock list and read
 774                 Mutex_Acquire( &conn->lRecievedPackets );
 775                 #else
 776                 // Lock list and check if there is a packet
 777                 Mutex_Acquire( &conn->lRecievedPackets );
 778                 if( conn->RecievedBuffer->Length == 0 ) {
 779                         // If not, release the lock, yield and try again
 780                         Mutex_Release( &conn->lRecievedPackets );
 781                         Threads_Yield();        // TODO: Less expensive wait
 782                         continue;
 783                 }
 784                 #endif
 785
 786                 // Attempt to read all `Length` bytes
 787                 len = RingBuffer_Read( destbuf, conn->RecievedBuffer, Length );
 788
 789                 #if USE_SELECT
 790                 if( conn->RecievedBuffer->Length == 0 )
 791                         VFS_MarkAvaliable(Node, 0);
 792                 #endif
 793
 794                 // Release the lock (we don't need it any more)
 795                 Mutex_Release( &conn->lRecievedPackets );
 796
 797                 LEAVE('i', len);
 798                 return len;
 799         }
 800 }
 801
 802 /**
 803  * \brief Send a data packet on a connection
 804  */
 805 void TCP_INT_SendDataPacket(tTCPConnection *Connection, size_t Length, void *Data)
 806 {
 807         char    buf[sizeof(tTCPHeader)+Length];
 808         tTCPHeader      *packet = (void*)buf;
 809
 810         packet->SourcePort = htons(Connection->LocalPort);
 811         packet->DestPort = htons(Connection->RemotePort);
 812         packet->DataOffset = (sizeof(tTCPHeader)/4)*16;
 813         packet->WindowSize = TCP_WINDOW_SIZE;
 814
 815         packet->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 816         packet->SequenceNumber = htonl(Connection->NextSequenceSend);
 817         packet->Flags = TCP_FLAG_PSH|TCP_FLAG_ACK;      // Hey, ACK if you can!
 818
 819         memcpy(packet->Options, Data, Length);
 820
 821         TCP_SendPacket( Connection, sizeof(tTCPHeader)+Length, packet );
 822
 823         Connection->NextSequenceSend += Length;
 824 }
 825
 826 /**
 827  * \brief Send some bytes on a connection
 828  */
 829 Uint64 TCP_Client_Write(tVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer)
 830 {
 831         tTCPConnection  *conn = Node->ImplPtr;
 832         size_t  rem = Length;
 833
 834         ENTER("pNode XOffset XLength pBuffer", Node, Offset, Length, Buffer);
 835
 836         // Check if connection is open
 837         while( conn->State == TCP_ST_HALFOPEN || conn->State == TCP_ST_SYN_SENT )
 838                 Threads_Yield();
 839         if( conn->State != TCP_ST_OPEN ) {
 840                 LEAVE('i', 0);
 841                 return 0;
 842         }
 843
 844         while( rem > TCP_MAX_PACKET_SIZE )
 845         {
 846                 TCP_INT_SendDataPacket(conn, TCP_MAX_PACKET_SIZE, Buffer);
 847                 Buffer += TCP_MAX_PACKET_SIZE;
 848         }
 849
 850         TCP_INT_SendDataPacket(conn, rem, Buffer);
 851
 852         LEAVE('i', Length);
 853         return Length;
 854 }
 855
 856 /**
 857  * \brief Open a connection to another host using TCP
 858  * \param Conn  Connection structure
 859  */
 860 void TCP_StartConnection(tTCPConnection *Conn)
 861 {
 862         tTCPHeader      hdr = {0};
 863
 864         Conn->State = TCP_ST_SYN_SENT;
 865
 866         hdr.SourcePort = htons(Conn->LocalPort);
 867         hdr.DestPort = htons(Conn->RemotePort);
 868         Conn->NextSequenceSend = rand();
 869         hdr.SequenceNumber = htonl(Conn->NextSequenceSend);
 870         hdr.DataOffset = (sizeof(tTCPHeader)/4) << 4;
 871         hdr.Flags = TCP_FLAG_SYN;
 872         hdr.WindowSize = htons(TCP_WINDOW_SIZE);        // Max
 873         hdr.Checksum = 0;       // TODO
 874
 875         TCP_SendPacket( Conn, sizeof(tTCPHeader), &hdr );
 876
 877         Conn->NextSequenceSend ++;
 878         Conn->State = TCP_ST_SYN_SENT;
 879         return ;
 880 }
 881
 882 /**
 883  * \brief Control a client socket
 884  */
 885 int TCP_Client_IOCtl(tVFS_Node *Node, int ID, void *Data)
 886 {
 887         tTCPConnection  *conn = Node->ImplPtr;
 888
 889         ENTER("pNode iID pData", Node, ID, Data);
 890
 891         switch(ID)
 892         {
 893         case 4: // Get/Set local port
 894                 if(!Data)
 895                         LEAVE_RET('i', conn->LocalPort);
 896                 if(conn->State != TCP_ST_CLOSED)
 897                         LEAVE_RET('i', -1);
 898                 if(!CheckMem(Data, sizeof(Uint16)))
 899                         LEAVE_RET('i', -1);
 900
 901                 if(Threads_GetUID() != 0 && *(Uint16*)Data < 1024)
 902                         LEAVE_RET('i', -1);
 903
 904                 conn->LocalPort = *(Uint16*)Data;
 905                 LEAVE_RET('i', conn->LocalPort);
 906
 907         case 5: // Get/Set remote port
 908                 if(!Data)       LEAVE_RET('i', conn->RemotePort);
 909                 if(conn->State != TCP_ST_CLOSED)        LEAVE_RET('i', -1);
 910                 if(!CheckMem(Data, sizeof(Uint16)))     LEAVE_RET('i', -1);
 911                 conn->RemotePort = *(Uint16*)Data;
 912                 LEAVE_RET('i', conn->RemotePort);
 913
 914         case 6: // Set Remote IP
 915                 if( conn->State != TCP_ST_CLOSED )
 916                         LEAVE_RET('i', -1);
 917                 if( conn->Interface->Type == 4 )
 918                 {
 919                         if(!CheckMem(Data, sizeof(tIPv4)))      LEAVE_RET('i', -1);
 920                         conn->RemoteIP.v4 = *(tIPv4*)Data;
 921                 }
 922                 else if( conn->Interface->Type == 6 )
 923                 {
 924                         if(!CheckMem(Data, sizeof(tIPv6)))      LEAVE_RET('i', -1);
 925                         conn->RemoteIP.v6 = *(tIPv6*)Data;
 926                 }
 927                 LEAVE_RET('i', 0);
 928
 929         case 7: // Connect
 930                 if(conn->LocalPort == 0xFFFF)
 931                         conn->LocalPort = TCP_GetUnusedPort();
 932                 if(conn->RemotePort == -1)
 933                         LEAVE_RET('i', 0);
 934
 935                 TCP_StartConnection(conn);
 936                 LEAVE_RET('i', 1);
 937
 938         // Get recieve buffer length
 939         case 8:
 940                 LEAVE_RET('i', conn->RecievedBuffer->Length);
 941         }
 942
 943         return 0;
 944 }
 945
 946 void TCP_Client_Close(tVFS_Node *Node)
 947 {
 948         tTCPConnection  *conn = Node->ImplPtr;
 949         tTCPHeader      packet;
 950
 951         ENTER("pNode", Node);
 952
 953         packet.SourcePort = htons(conn->LocalPort);
 954         packet.DestPort = htons(conn->RemotePort);
 955         packet.DataOffset = (sizeof(tTCPHeader)/4)*16;
 956         packet.WindowSize = TCP_WINDOW_SIZE;
 957
 958         packet.AcknowlegementNumber = 0;
 959         packet.SequenceNumber = htonl(conn->NextSequenceSend);
 960         packet.Flags = TCP_FLAG_FIN;
 961
 962         conn->State = TCP_ST_FIN_SENT;
 963
 964         TCP_SendPacket( conn, sizeof(tTCPHeader), &packet );
 965
 966         while( conn->State == TCP_ST_FIN_SENT ) Threads_Yield();
 967
 968         free(conn);
 969
 970         LEAVE('-');
 971 }