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 USE_SELECT      1
  11
  12 #define TCP_MIN_DYNPORT 0xC000
  13 #define TCP_MAX_HALFOPEN        1024    // Should be enough
  14
  15 #define TCP_MAX_PACKET_SIZE     1024
  16 #define TCP_WINDOW_SIZE 0x2000
  17 #define TCP_RECIEVE_BUFFER_SIZE 0x4000
  18
  19 // === PROTOTYPES ===
  20 void    TCP_Initialise();
  21 void    TCP_StartConnection(tTCPConnection *Conn);
  22 void    TCP_SendPacket(tTCPConnection *Conn, size_t Length, tTCPHeader *Data);
  23 void    TCP_GetPacket(tInterface *Interface, void *Address, int Length, void *Buffer);
  24 void    TCP_INT_HandleConnectionPacket(tTCPConnection *Connection, tTCPHeader *Header, int Length);
  25 void    TCP_INT_AppendRecieved(tTCPConnection *Connection, tTCPStoredPacket *Ptk);
  26 void    TCP_INT_UpdateRecievedFromFuture(tTCPConnection *Connection);
  27 Uint16  TCP_GetUnusedPort();
  28  int    TCP_AllocatePort(Uint16 Port);
  29  int    TCP_DeallocatePort(Uint16 Port);
  30 // --- Server
  31 tVFS_Node       *TCP_Server_Init(tInterface *Interface);
  32 char    *TCP_Server_ReadDir(tVFS_Node *Node, int Pos);
  33 tVFS_Node       *TCP_Server_FindDir(tVFS_Node *Node, const char *Name);
  34  int    TCP_Server_IOCtl(tVFS_Node *Node, int ID, void *Data);
  35 void    TCP_Server_Close(tVFS_Node *Node);
  36 // --- Client
  37 tVFS_Node       *TCP_Client_Init(tInterface *Interface);
  38 Uint64  TCP_Client_Read(tVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer);
  39 Uint64  TCP_Client_Write(tVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer);
  40  int    TCP_Client_IOCtl(tVFS_Node *Node, int ID, void *Data);
  41 void    TCP_Client_Close(tVFS_Node *Node);
  42
  43 // === TEMPLATES ===
  44 tSocketFile     gTCP_ServerFile = {NULL, "tcps", TCP_Server_Init};
  45 tSocketFile     gTCP_ClientFile = {NULL, "tcpc", TCP_Client_Init};
  46
  47 // === GLOBALS ===
  48  int    giTCP_NumHalfopen = 0;
  49 tShortSpinlock  glTCP_Listeners;
  50 tTCPListener    *gTCP_Listeners;
  51 tShortSpinlock  glTCP_OutbountCons;
  52 tTCPConnection  *gTCP_OutbountCons;
  53 Uint32  gaTCP_PortBitmap[0x800];
  54  int    giTCP_NextOutPort = TCP_MIN_DYNPORT;
  55
  56 // === CODE ===
  57 /**
  58  * \brief Initialise the TCP Layer
  59  *
  60  * Registers the client and server files and the GetPacket callback
  61  */
  62 void TCP_Initialise()
  63 {
  64         IPStack_AddFile(&gTCP_ServerFile);
  65         IPStack_AddFile(&gTCP_ClientFile);
  66         IPv4_RegisterCallback(IP4PROT_TCP, TCP_GetPacket);
  67 }
  68
  69 /**
  70  * \brief Sends a packet from the specified connection, calculating the checksums
  71  * \param Conn  Connection
  72  * \param Length        Length of data
  73  * \param Data  Packet data (cast as a TCP Header)
  74  */
  75 void TCP_SendPacket( tTCPConnection *Conn, size_t Length, tTCPHeader *Data )
  76 {
  77         size_t  buflen;
  78         Uint32  *buf;
  79         switch( Conn->Interface->Type )
  80         {
  81         case 4: // Append IPv4 Pseudo Header
  82                 buflen = 4 + 4 + 4 + ((Length+1)&~1);
  83                 buf = malloc( buflen );
  84                 buf[0] = ((tIPv4*)Conn->Interface->Address)->L;
  85                 buf[1] = Conn->RemoteIP.v4.L;
  86                 buf[2] = (htons(Length)<<16) | (6<<8) | 0;
  87                 Data->Checksum = 0;
  88                 memcpy( &buf[3], Data, Length );
  89                 Data->Checksum = htons( IPv4_Checksum( buf, buflen ) );
  90                 free(buf);
  91                 IPv4_SendPacket(Conn->Interface, Conn->RemoteIP.v4, IP4PROT_TCP, 0, Length, Data);
  92                 break;
  93         }
  94 }
  95
  96 /**
  97  * \brief Handles a packet from the IP Layer
  98  * \param Interface     Interface the packet arrived from
  99  * \param Address       Pointer to the addres structure
 100  * \param Length        Size of packet in bytes
 101  * \param Buffer        Packet data
 102  */
 103 void TCP_GetPacket(tInterface *Interface, void *Address, int Length, void *Buffer)
 104 {
 105         tTCPHeader      *hdr = Buffer;
 106         tTCPListener    *srv;
 107         tTCPConnection  *conn;
 108
 109         Log_Log("TCP", "TCP_GetPacket: SourcePort = %i, DestPort = %i",
 110                 ntohs(hdr->SourcePort), ntohs(hdr->DestPort));
 111 /*
 112         Log_Log("TCP", "TCP_GetPacket: SequenceNumber = 0x%x", ntohl(hdr->SequenceNumber));
 113         Log_Log("TCP", "TCP_GetPacket: AcknowlegementNumber = 0x%x", ntohl(hdr->AcknowlegementNumber));
 114         Log_Log("TCP", "TCP_GetPacket: DataOffset = %i", hdr->DataOffset >> 4);
 115         Log_Log("TCP", "TCP_GetPacket: Flags = {");
 116         Log_Log("TCP", "TCP_GetPacket:   CWR = %B, ECE = %B",
 117                 !!(hdr->Flags & TCP_FLAG_CWR), !!(hdr->Flags & TCP_FLAG_ECE));
 118         Log_Log("TCP", "TCP_GetPacket:   URG = %B, ACK = %B",
 119                 !!(hdr->Flags & TCP_FLAG_URG), !!(hdr->Flags & TCP_FLAG_ACK));
 120         Log_Log("TCP", "TCP_GetPacket:   PSH = %B, RST = %B",
 121                 !!(hdr->Flags & TCP_FLAG_PSH), !!(hdr->Flags & TCP_FLAG_RST));
 122         Log_Log("TCP", "TCP_GetPacket:   SYN = %B, FIN = %B",
 123                 !!(hdr->Flags & TCP_FLAG_SYN), !!(hdr->Flags & TCP_FLAG_FIN));
 124         Log_Log("TCP", "TCP_GetPacket: }");
 125         Log_Log("TCP", "TCP_GetPacket: WindowSize = %i", htons(hdr->WindowSize));
 126         Log_Log("TCP", "TCP_GetPacket: Checksum = 0x%x", htons(hdr->Checksum));
 127         Log_Log("TCP", "TCP_GetPacket: UrgentPointer = 0x%x", htons(hdr->UrgentPointer));
 128 */
 129         Log_Log("TCP", "TCP_GetPacket: Flags = %s%s%s%s%s%s",
 130                 (hdr->Flags & TCP_FLAG_CWR) ? "CWR " : "",
 131                 (hdr->Flags & TCP_FLAG_ECE) ? "ECE " : "",
 132                 (hdr->Flags & TCP_FLAG_URG) ? "URG " : "",
 133                 (hdr->Flags & TCP_FLAG_ACK) ? "ACK " : "",
 134                 (hdr->Flags & TCP_FLAG_PSH) ? "PSH " : "",
 135                 (hdr->Flags & TCP_FLAG_RST) ? "RST " : "",
 136                 (hdr->Flags & TCP_FLAG_SYN) ? "SYN " : "",
 137                 (hdr->Flags & TCP_FLAG_FIN) ? "FIN " : ""
 138                 );
 139
 140         if( Length > (hdr->DataOffset >> 4)*4 )
 141         {
 142                 Debug_HexDump(
 143                         "[TCP  ] Packet Data = ",
 144                         (Uint8*)hdr + (hdr->DataOffset >> 4)*4,
 145                         Length - (hdr->DataOffset >> 4)*4
 146                         );
 147         }
 148
 149         // Check Servers
 150         {
 151                 for( srv = gTCP_Listeners; srv; srv = srv->Next )
 152                 {
 153                         // Check if the server is active
 154                         if(srv->Port == 0)      continue;
 155                         // Check the interface
 156                         if(srv->Interface && srv->Interface != Interface)       continue;
 157                         // Check the destination port
 158                         if(srv->Port != htons(hdr->DestPort))   continue;
 159
 160                         Log_Log("TCP", "TCP_GetPacket: Matches server %p", srv);
 161                         // Is this in an established connection?
 162                         for( conn = srv->Connections; conn; conn = conn->Next )
 163                         {
 164                                 Log_Log("TCP", "TCP_GetPacket: conn->Interface(%p) == Interface(%p)",
 165                                         conn->Interface, Interface);
 166                                 // Check that it is coming in on the same interface
 167                                 if(conn->Interface != Interface)        continue;
 168
 169                                 // Check Source Port
 170                                 Log_Log("TCP", "TCP_GetPacket: conn->RemotePort(%i) == hdr->SourcePort(%i)",
 171                                         conn->RemotePort, ntohs(hdr->SourcePort));
 172                                 if(conn->RemotePort != ntohs(hdr->SourcePort))  continue;
 173
 174                                 // Check Source IP
 175                                 if(conn->Interface->Type == 6 && !IP6_EQU(conn->RemoteIP.v6, *(tIPv6*)Address))
 176                                         continue;
 177                                 if(conn->Interface->Type == 4 && !IP4_EQU(conn->RemoteIP.v4, *(tIPv4*)Address))
 178                                         continue;
 179
 180                                 Log_Log("TCP", "TCP_GetPacket: Matches connection %p", conn);
 181                                 // We have a response!
 182                                 TCP_INT_HandleConnectionPacket(conn, hdr, Length);
 183
 184                                 return;
 185                         }
 186
 187                         Log_Log("TCP", "TCP_GetPacket: Opening Connection");
 188                         // Open a new connection (well, check that it's a SYN)
 189                         if(hdr->Flags != TCP_FLAG_SYN) {
 190                                 Log_Log("TCP", "TCP_GetPacket: Packet is not a SYN");
 191                                 return ;
 192                         }
 193
 194                         // TODO: Check for halfopen max
 195
 196                         conn = calloc(1, sizeof(tTCPConnection));
 197                         conn->State = TCP_ST_HALFOPEN;
 198                         conn->LocalPort = srv->Port;
 199                         conn->RemotePort = ntohs(hdr->SourcePort);
 200                         conn->Interface = Interface;
 201
 202                         switch(Interface->Type)
 203                         {
 204                         case 4: conn->RemoteIP.v4 = *(tIPv4*)Address;   break;
 205                         case 6: conn->RemoteIP.v6 = *(tIPv6*)Address;   break;
 206                         }
 207
 208                         conn->RecievedBuffer = RingBuffer_Create( TCP_RECIEVE_BUFFER_SIZE );
 209
 210                         conn->NextSequenceRcv = ntohl( hdr->SequenceNumber ) + 1;
 211                         conn->NextSequenceSend = rand();
 212
 213                         // Create node
 214                         conn->Node.NumACLs = 1;
 215                         conn->Node.ACLs = &gVFS_ACL_EveryoneRW;
 216                         conn->Node.ImplPtr = conn;
 217                         conn->Node.ImplInt = srv->NextID ++;
 218                         conn->Node.Read = TCP_Client_Read;
 219                         conn->Node.Write = TCP_Client_Write;
 220                         //conn->Node.Close = TCP_SrvConn_Close;
 221
 222                         // Hmm... Theoretically, this lock will never have to wait,
 223                         // as the interface is locked to the watching thread, and this
 224                         // runs in the watching thread. But, it's a good idea to have
 225                         // it, just in case
 226                         // Oh, wait, there is a case where a wildcard can be used
 227                         // (srv->Interface == NULL) so having the lock is a good idea
 228                         SHORTLOCK(&srv->lConnections);
 229                         if( !srv->Connections )
 230                                 srv->Connections = conn;
 231                         else
 232                                 srv->ConnectionsTail->Next = conn;
 233                         srv->ConnectionsTail = conn;
 234                         if(!srv->NewConnections)
 235                                 srv->NewConnections = conn;
 236                         SHORTREL(&srv->lConnections);
 237
 238                         // Send the SYN ACK
 239                         hdr->Flags |= TCP_FLAG_ACK;
 240                         hdr->AcknowlegementNumber = htonl(conn->NextSequenceRcv);
 241                         hdr->SequenceNumber = htonl(conn->NextSequenceSend);
 242                         hdr->DestPort = hdr->SourcePort;
 243                         hdr->SourcePort = htons(srv->Port);
 244                         hdr->DataOffset = (sizeof(tTCPHeader)/4) << 4;
 245                         TCP_SendPacket( conn, sizeof(tTCPHeader), hdr );
 246                         conn->NextSequenceSend ++;
 247                         return ;
 248                 }
 249         }
 250
 251
 252         // Check Open Connections
 253         {
 254                 for( conn = gTCP_OutbountCons; conn; conn = conn->Next )
 255                 {
 256                         // Check that it is coming in on the same interface
 257                         if(conn->Interface != Interface)        continue;
 258
 259                         // Check Source Port
 260                         if(conn->RemotePort != ntohs(hdr->SourcePort))  continue;
 261
 262                         // Check Source IP
 263                         if(conn->Interface->Type == 6 && !IP6_EQU(conn->RemoteIP.v6, *(tIPv6*)Address))
 264                                 continue;
 265                         if(conn->Interface->Type == 4 && !IP4_EQU(conn->RemoteIP.v4, *(tIPv4*)Address))
 266                                 continue;
 267
 268                         TCP_INT_HandleConnectionPacket(conn, hdr, Length);
 269                         return ;
 270                 }
 271         }
 272
 273         Log_Log("TCP", "TCP_GetPacket: No Match");
 274 }
 275
 276 /**
 277  * \brief Handles a packet sent to a specific connection
 278  * \param Connection    TCP Connection pointer
 279  * \param Header        TCP Packet pointer
 280  * \param Length        Length of the packet
 281  */
 282 void TCP_INT_HandleConnectionPacket(tTCPConnection *Connection, tTCPHeader *Header, int Length)
 283 {
 284         tTCPStoredPacket        *pkt;
 285          int    dataLen;
 286
 287         // Syncronise sequence values
 288         if(Header->Flags & TCP_FLAG_SYN) {
 289                 Connection->NextSequenceRcv = ntohl(Header->SequenceNumber) + 1;
 290         }
 291
 292         // Handle a server replying to our initial SYN
 293         if( Connection->State == TCP_ST_SYN_SENT )
 294         {
 295                 if( (Header->Flags & (TCP_FLAG_SYN|TCP_FLAG_ACK)) == (TCP_FLAG_SYN|TCP_FLAG_ACK) )
 296                 {
 297                         Header->DestPort = Header->SourcePort;
 298                         Header->SourcePort = htons(Connection->LocalPort);
 299                         Header->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 300                         Header->SequenceNumber = htonl(Connection->NextSequenceSend);
 301                         Header->WindowSize = htons(TCP_WINDOW_SIZE);
 302                         Header->Flags = TCP_FLAG_ACK;
 303                         Header->DataOffset = (sizeof(tTCPHeader)/4) << 4;
 304                         Log_Log("TCP", "ACKing SYN-ACK");
 305                         TCP_SendPacket( Connection, sizeof(tTCPHeader), Header );
 306                         Connection->State = TCP_ST_OPEN;
 307                 }
 308         }
 309
 310         // Handle a client confirming the connection
 311         if( Connection->State == TCP_ST_HALFOPEN && (Header->Flags & TCP_FLAG_ACK) )
 312         {
 313                 Connection->State = TCP_ST_OPEN;
 314                 Log_Log("TCP", "Connection fully opened");
 315         }
 316
 317         // Get length of data
 318         dataLen = Length - (Header->DataOffset>>4)*4;
 319         Log_Log("TCP", "HandleConnectionPacket - dataLen = %i", dataLen);
 320
 321         if(Header->Flags & TCP_FLAG_ACK) {
 322                 // TODO: Process an ACKed Packet
 323                 Log_Log("TCP", "Conn %p, Packet 0x%x ACKed", Connection, Header->AcknowlegementNumber);
 324
 325                 // HACK
 326                 // TODO: Make sure that the packet is actually ACKing the FIN
 327                 if( Connection->State == TCP_ST_FIN_SENT ) {
 328                         Connection->State = TCP_ST_FINISHED;
 329                         return ;
 330                 }
 331         }
 332
 333         // TODO: Check what to do here
 334         if(Header->Flags & TCP_FLAG_FIN) {
 335                 if( Connection->State == TCP_ST_FIN_SENT ) {
 336                         Connection->State = TCP_ST_FINISHED;
 337                         return ;
 338                 }
 339                 else {
 340                         Connection->State = TCP_ST_FINISHED;
 341                         Header->DestPort = Header->SourcePort;
 342                         Header->SourcePort = htons(Connection->LocalPort);
 343                         Header->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 344                         Header->SequenceNumber = htonl(Connection->NextSequenceSend);
 345                         Header->Flags = TCP_FLAG_ACK;
 346                         TCP_SendPacket( Connection, sizeof(tTCPHeader), Header );
 347                         return ;
 348                 }
 349         }
 350
 351         // Check for an empty packet
 352         if(dataLen == 0) {
 353                 Log_Log("TCP", "Empty Packet");
 354                 return ;
 355         }
 356
 357         // NOTES:
 358         // Flags
 359         //    PSH - Has Data?
 360         // /NOTES
 361
 362         // Allocate and fill cached packet
 363         pkt = malloc( dataLen + sizeof(tTCPStoredPacket) );
 364         pkt->Next = NULL;
 365         pkt->Sequence = ntohl(Header->SequenceNumber);
 366         pkt->Length = dataLen;
 367         memcpy(pkt->Data, (Uint8*)Header + (Header->DataOffset>>4)*4, dataLen);
 368
 369         // Is this packet the next expected packet?
 370         // TODO: Fix this to check if the packet is in the window.
 371         if( pkt->Sequence != Connection->NextSequenceRcv )
 372         {
 373                 tTCPStoredPacket        *tmp, *prev = NULL;
 374
 375                 Log_Log("TCP", "Out of sequence packet (0x%08x != 0x%08x)",
 376                         pkt->Sequence, Connection->NextSequenceRcv);
 377
 378                 // No? Well, let's cache it and look at it later
 379                 SHORTLOCK( &Connection->lFuturePackets );
 380                 for(tmp = Connection->FuturePackets;
 381                         tmp;
 382                         prev = tmp, tmp = tmp->Next)
 383                 {
 384                         if(tmp->Sequence > pkt->Sequence)       break;
 385                 }
 386                 if(prev)
 387                         prev->Next = pkt;
 388                 else
 389                         Connection->FuturePackets = pkt;
 390                 pkt->Next = tmp;
 391                 SHORTREL( &Connection->lFuturePackets );
 392         }
 393         else
 394         {
 395                 // Ooh, Goodie! Add it to the recieved list
 396                 TCP_INT_AppendRecieved(Connection, pkt);
 397                 free(pkt);
 398                 Log_Log("TCP", "0x%08x += %i", Connection->NextSequenceRcv, dataLen);
 399                 Connection->NextSequenceRcv += dataLen;
 400
 401                 // TODO: This should be moved out of the watcher thread,
 402                 // so that a single lost packet on one connection doesn't cause
 403                 // all connections on the interface to lag.
 404                 TCP_INT_UpdateRecievedFromFuture(Connection);
 405
 406                 // ACK Packet
 407                 Header->DestPort = Header->SourcePort;
 408                 Header->SourcePort = htons(Connection->LocalPort);
 409                 Header->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 410                 Header->SequenceNumber = htonl(Connection->NextSequenceSend);
 411                 Header->WindowSize = htons(TCP_WINDOW_SIZE);
 412                 Header->Flags &= TCP_FLAG_SYN;  // Eliminate all flags save for SYN
 413                 Header->Flags |= TCP_FLAG_ACK;  // Add ACK
 414                 Log_Log("TCP", "Sending ACK for 0x%08x", Connection->NextSequenceRcv);
 415                 TCP_SendPacket( Connection, sizeof(tTCPHeader), Header );
 416                 //Connection->NextSequenceSend ++;
 417         }
 418 }
 419
 420 /**
 421  * \brief Appends a packet to the recieved list
 422  * \param Connection    Connection structure
 423  * \param Pkt   Packet structure on heap
 424  */
 425 void TCP_INT_AppendRecieved(tTCPConnection *Connection, tTCPStoredPacket *Pkt)
 426 {
 427         Mutex_Acquire( &Connection->lRecievedPackets );
 428         if(Connection->RecievedBuffer->Length + Pkt->Length > Connection->RecievedBuffer->Space )
 429         {
 430                 Log_Error("TCP", "Buffer filled, packet dropped (%s)",
 431                 //      TCP_INT_DumpConnection(Connection)
 432                         ""
 433                         );
 434                 return ;
 435         }
 436
 437         RingBuffer_Write( Connection->RecievedBuffer, Pkt->Data, Pkt->Length );
 438
 439         #if USE_SELECT
 440         VFS_MarkAvaliable(&Connection->Node, 1);
 441         #endif
 442
 443         Mutex_Release( &Connection->lRecievedPackets );
 444 }
 445
 446 /**
 447  * \brief Updates the connections recieved list from the future list
 448  * \param Connection    Connection structure
 449  *
 450  * Updates the recieved packets list with packets from the future (out
 451  * of order) packets list that are now able to be added in direct
 452  * sequence.
 453  */
 454 void TCP_INT_UpdateRecievedFromFuture(tTCPConnection *Connection)
 455 {
 456         tTCPStoredPacket        *pkt, *prev;
 457         for(;;)
 458         {
 459                 prev = NULL;
 460                 // Look for the next expected packet in the cache.
 461                 SHORTLOCK( &Connection->lFuturePackets );
 462                 for(pkt = Connection->FuturePackets;
 463                         pkt && pkt->Sequence < Connection->NextSequenceRcv;
 464                         prev = pkt, pkt = pkt->Next);
 465
 466                 // If we can't find the expected next packet, stop looking
 467                 if(!pkt || pkt->Sequence > Connection->NextSequenceRcv) {
 468                         SHORTREL( &Connection->lFuturePackets );
 469                         return;
 470                 }
 471
 472                 // Delete packet from future list
 473                 if(prev)
 474                         prev->Next = pkt->Next;
 475                 else
 476                         Connection->FuturePackets = pkt->Next;
 477
 478                 // Release list
 479                 SHORTREL( &Connection->lFuturePackets );
 480
 481                 // Looks like we found one
 482                 TCP_INT_AppendRecieved(Connection, pkt);
 483                 Connection->NextSequenceRcv += pkt->Length;
 484                 free(pkt);
 485         }
 486 }
 487
 488 /**
 489  * \fn Uint16 TCP_GetUnusedPort()
 490  * \brief Gets an unused port and allocates it
 491  */
 492 Uint16 TCP_GetUnusedPort()
 493 {
 494         Uint16  ret;
 495
 496         // Get Next outbound port
 497         ret = giTCP_NextOutPort++;
 498         while( gaTCP_PortBitmap[ret/32] & (1 << (ret%32)) )
 499         {
 500                 ret ++;
 501                 giTCP_NextOutPort++;
 502                 if(giTCP_NextOutPort == 0x10000) {
 503                         ret = giTCP_NextOutPort = TCP_MIN_DYNPORT;
 504                 }
 505         }
 506
 507         // Mark the new port as used
 508         gaTCP_PortBitmap[ret/32] |= 1 << (ret%32);
 509
 510         return ret;
 511 }
 512
 513 /**
 514  * \fn int TCP_AllocatePort(Uint16 Port)
 515  * \brief Marks a port as used
 516  */
 517 int TCP_AllocatePort(Uint16 Port)
 518 {
 519         // Check if the port has already been allocated
 520         if( gaTCP_PortBitmap[Port/32] & (1 << (Port%32)) )
 521                 return 0;
 522
 523         // Allocate
 524         gaTCP_PortBitmap[Port/32] |= 1 << (Port%32);
 525
 526         return 1;
 527 }
 528
 529 /**
 530  * \fn int TCP_DeallocatePort(Uint16 Port)
 531  * \brief Marks a port as unused
 532  */
 533 int TCP_DeallocatePort(Uint16 Port)
 534 {
 535         // Check if the port has already been allocated
 536         if( !(gaTCP_PortBitmap[Port/32] & (1 << (Port%32))) )
 537                 return 0;
 538
 539         // Allocate
 540         gaTCP_PortBitmap[Port/32] &= ~(1 << (Port%32));
 541
 542         return 1;
 543 }
 544
 545 // --- Server
 546 tVFS_Node *TCP_Server_Init(tInterface *Interface)
 547 {
 548         tTCPListener    *srv;
 549
 550         srv = malloc( sizeof(tTCPListener) );
 551
 552         if( srv == NULL ) {
 553                 Log_Warning("TCP", "malloc failed for listener (%i) bytes", sizeof(tTCPListener));
 554                 return NULL;
 555         }
 556
 557         srv->Interface = Interface;
 558         srv->Port = 0;
 559         srv->NextID = 0;
 560         srv->Connections = NULL;
 561         srv->ConnectionsTail = NULL;
 562         srv->NewConnections = NULL;
 563         srv->Next = NULL;
 564         srv->Node.Flags = VFS_FFLAG_DIRECTORY;
 565         srv->Node.Size = -1;
 566         srv->Node.ImplPtr = srv;
 567         srv->Node.NumACLs = 1;
 568         srv->Node.ACLs = &gVFS_ACL_EveryoneRW;
 569         srv->Node.ReadDir = TCP_Server_ReadDir;
 570         srv->Node.FindDir = TCP_Server_FindDir;
 571         srv->Node.IOCtl = TCP_Server_IOCtl;
 572         srv->Node.Close = TCP_Server_Close;
 573
 574         SHORTLOCK(&glTCP_Listeners);
 575         srv->Next = gTCP_Listeners;
 576         gTCP_Listeners = srv;
 577         SHORTREL(&glTCP_Listeners);
 578
 579         return &srv->Node;
 580 }
 581
 582 /**
 583  * \brief Wait for a new connection and return the connection ID
 584  * \note Blocks until a new connection is made
 585  * \param Node  Server node
 586  * \param Pos   Position (ignored)
 587  */
 588 char *TCP_Server_ReadDir(tVFS_Node *Node, int Pos)
 589 {
 590         tTCPListener    *srv = Node->ImplPtr;
 591         tTCPConnection  *conn;
 592         char    *ret;
 593
 594         ENTER("pNode iPos", Node, Pos);
 595
 596         Log_Log("TCP", "Thread %i waiting for a connection", Threads_GetTID());
 597         for(;;)
 598         {
 599                 SHORTLOCK( &srv->lConnections );
 600                 if( srv->NewConnections != NULL )       break;
 601                 SHORTREL( &srv->lConnections );
 602                 Threads_Yield();        // TODO: Sleep until poked
 603                 continue;
 604         }
 605
 606
 607         // Increment the new list (the current connection is still on the
 608         // normal list)
 609         conn = srv->NewConnections;
 610         srv->NewConnections = conn->Next;
 611
 612         SHORTREL( &srv->lConnections );
 613
 614         LOG("conn = %p", conn);
 615         LOG("srv->Connections = %p", srv->Connections);
 616         LOG("srv->NewConnections = %p", srv->NewConnections);
 617         LOG("srv->ConnectionsTail = %p", srv->ConnectionsTail);
 618
 619         ret = malloc(9);
 620         itoa(ret, conn->Node.ImplInt, 16, 8, '0');
 621         Log_Log("TCP", "Thread %i got '%s'", Threads_GetTID(), ret);
 622         LEAVE('s', ret);
 623         return ret;
 624 }
 625
 626 /**
 627  * \brief Gets a client connection node
 628  * \param Node  Server node
 629  * \param Name  Hexadecimal ID of the node
 630  */
 631 tVFS_Node *TCP_Server_FindDir(tVFS_Node *Node, const char *Name)
 632 {
 633         tTCPConnection  *conn;
 634         tTCPListener    *srv = Node->ImplPtr;
 635         char    tmp[9];
 636          int    id = atoi(Name);
 637
 638         ENTER("pNode sName", Node, Name);
 639
 640         // Sanity Check
 641         itoa(tmp, id, 16, 8, '0');
 642         if(strcmp(tmp, Name) != 0) {
 643                 LOG("'%s' != '%s' (%08x)", Name, tmp, id);
 644                 LEAVE('n');
 645                 return NULL;
 646         }
 647
 648         Log_Debug("TCP", "srv->Connections = %p", srv->Connections);
 649         Log_Debug("TCP", "srv->NewConnections = %p", srv->NewConnections);
 650         Log_Debug("TCP", "srv->ConnectionsTail = %p", srv->ConnectionsTail);
 651
 652         // Search
 653         SHORTLOCK( &srv->lConnections );
 654         for(conn = srv->Connections;
 655                 conn;
 656                 conn = conn->Next)
 657         {
 658                 LOG("conn->Node.ImplInt = %i", conn->Node.ImplInt);
 659                 if(conn->Node.ImplInt == id)    break;
 660         }
 661         SHORTREL( &srv->lConnections );
 662
 663         // If not found, ret NULL
 664         if(!conn) {
 665                 LOG("Connection %i not found", id);
 666                 LEAVE('n');
 667                 return NULL;
 668         }
 669
 670         // Return node
 671         LEAVE('p', &conn->Node);
 672         return &conn->Node;
 673 }
 674
 675 /**
 676  * \brief Handle IOCtl calls
 677  */
 678 int TCP_Server_IOCtl(tVFS_Node *Node, int ID, void *Data)
 679 {
 680         tTCPListener    *srv = Node->ImplPtr;
 681
 682         switch(ID)
 683         {
 684         case 4: // Get/Set Port
 685                 if(!Data)       // Get Port
 686                         return srv->Port;
 687
 688                 if(srv->Port)   // Wait, you can't CHANGE the port
 689                         return -1;
 690
 691                 if(!CheckMem(Data, sizeof(Uint16)))     // Sanity check
 692                         return -1;
 693
 694                 // Permissions check
 695                 if(Threads_GetUID() != 0
 696                 && *(Uint16*)Data != 0
 697                 && *(Uint16*)Data < 1024)
 698                         return -1;
 699
 700                 // TODO: Check if a port is in use
 701
 702                 // Set Port
 703                 srv->Port = *(Uint16*)Data;
 704                 if(srv->Port == 0)      // Allocate a random port
 705                         srv->Port = TCP_GetUnusedPort();
 706                 else    // Else, mark this as used
 707                         TCP_AllocatePort(srv->Port);
 708
 709                 Log_Log("TCP", "Server %p listening on port %i", srv, srv->Port);
 710
 711                 return srv->Port;
 712         }
 713         return 0;
 714 }
 715
 716 void TCP_Server_Close(tVFS_Node *Node)
 717 {
 718         free(Node->ImplPtr);
 719 }
 720
 721 // --- Client
 722 /**
 723  * \brief Create a client node
 724  */
 725 tVFS_Node *TCP_Client_Init(tInterface *Interface)
 726 {
 727         tTCPConnection  *conn = malloc( sizeof(tTCPConnection) );
 728
 729         conn->State = TCP_ST_CLOSED;
 730         conn->Interface = Interface;
 731         conn->LocalPort = -1;
 732         conn->RemotePort = -1;
 733         memset( &conn->RemoteIP, 0, sizeof(conn->RemoteIP) );
 734
 735         conn->Node.ImplPtr = conn;
 736         conn->Node.NumACLs = 1;
 737         conn->Node.ACLs = &gVFS_ACL_EveryoneRW;
 738         conn->Node.Read = TCP_Client_Read;
 739         conn->Node.Write = TCP_Client_Write;
 740         conn->Node.IOCtl = TCP_Client_IOCtl;
 741         conn->Node.Close = TCP_Client_Close;
 742
 743         conn->RecievedBuffer = RingBuffer_Create( TCP_RECIEVE_BUFFER_SIZE );
 744
 745         SHORTLOCK(&glTCP_OutbountCons);
 746         conn->Next = gTCP_OutbountCons;
 747         gTCP_OutbountCons = conn;
 748         SHORTREL(&glTCP_OutbountCons);
 749
 750         return &conn->Node;
 751 }
 752
 753 /**
 754  * \brief Wait for a packet and return it
 755  * \note If \a Length is smaller than the size of the packet, the rest
 756  *       of the packet's data will be discarded.
 757  */
 758 Uint64 TCP_Client_Read(tVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer)
 759 {
 760         tTCPConnection  *conn = Node->ImplPtr;
 761         char    *destbuf = Buffer;
 762         size_t  len;
 763
 764         ENTER("pNode XOffset XLength pBuffer", Node, Offset, Length, Buffer);
 765         LOG("conn = %p", conn);
 766         LOG("conn->State = %i", conn->State);
 767
 768         // Check if connection is open
 769         while( conn->State == TCP_ST_HALFOPEN || conn->State == TCP_ST_SYN_SENT )
 770                 Threads_Yield();
 771         if( conn->State != TCP_ST_OPEN ) {
 772                 LEAVE('i', 0);
 773                 return 0;
 774         }
 775
 776         // Poll packets
 777         for(;;)
 778         {
 779                 // Wait
 780                 VFS_SelectNode(Node, VFS_SELECT_READ, NULL);
 781                 // Lock list and read
 782                 Mutex_Acquire( &conn->lRecievedPackets );
 783
 784                 // Attempt to read all `Length` bytes
 785                 len = RingBuffer_Read( destbuf, conn->RecievedBuffer, Length );
 786
 787                 if( len == 0 || conn->RecievedBuffer->Length == 0 ) {
 788                         LOG("Marking as none avaliable (len = %i)\n", len);
 789                         VFS_MarkAvaliable(Node, 0);
 790                 }
 791
 792                 // Release the lock (we don't need it any more)
 793                 Mutex_Release( &conn->lRecievedPackets );
 794
 795                 LEAVE('i', len);
 796                 return len;
 797         }
 798 }
 799
 800 /**
 801  * \brief Send a data packet on a connection
 802  */
 803 void TCP_INT_SendDataPacket(tTCPConnection *Connection, size_t Length, void *Data)
 804 {
 805         char    buf[sizeof(tTCPHeader)+Length];
 806         tTCPHeader      *packet = (void*)buf;
 807
 808         packet->SourcePort = htons(Connection->LocalPort);
 809         packet->DestPort = htons(Connection->RemotePort);
 810         packet->DataOffset = (sizeof(tTCPHeader)/4)*16;
 811         packet->WindowSize = TCP_WINDOW_SIZE;
 812
 813         packet->AcknowlegementNumber = htonl(Connection->NextSequenceRcv);
 814         packet->SequenceNumber = htonl(Connection->NextSequenceSend);
 815         packet->Flags = TCP_FLAG_PSH|TCP_FLAG_ACK;      // Hey, ACK if you can!
 816
 817         memcpy(packet->Options, Data, Length);
 818
 819         TCP_SendPacket( Connection, sizeof(tTCPHeader)+Length, packet );
 820
 821         Connection->NextSequenceSend += Length;
 822 }
 823
 824 /**
 825  * \brief Send some bytes on a connection
 826  */
 827 Uint64 TCP_Client_Write(tVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer)
 828 {
 829         tTCPConnection  *conn = Node->ImplPtr;
 830         size_t  rem = Length;
 831
 832         ENTER("pNode XOffset XLength pBuffer", Node, Offset, Length, Buffer);
 833
 834         // Check if connection is open
 835         while( conn->State == TCP_ST_HALFOPEN || conn->State == TCP_ST_SYN_SENT )
 836                 Threads_Yield();
 837         if( conn->State != TCP_ST_OPEN ) {
 838                 LEAVE('i', 0);
 839                 return 0;
 840         }
 841
 842         while( rem > TCP_MAX_PACKET_SIZE )
 843         {
 844                 TCP_INT_SendDataPacket(conn, TCP_MAX_PACKET_SIZE, Buffer);
 845                 Buffer += TCP_MAX_PACKET_SIZE;
 846         }
 847
 848         TCP_INT_SendDataPacket(conn, rem, Buffer);
 849
 850         LEAVE('i', Length);
 851         return Length;
 852 }
 853
 854 /**
 855  * \brief Open a connection to another host using TCP
 856  * \param Conn  Connection structure
 857  */
 858 void TCP_StartConnection(tTCPConnection *Conn)
 859 {
 860         tTCPHeader      hdr = {0};
 861
 862         Conn->State = TCP_ST_SYN_SENT;
 863
 864         hdr.SourcePort = htons(Conn->LocalPort);
 865         hdr.DestPort = htons(Conn->RemotePort);
 866         Conn->NextSequenceSend = rand();
 867         hdr.SequenceNumber = htonl(Conn->NextSequenceSend);
 868         hdr.DataOffset = (sizeof(tTCPHeader)/4) << 4;
 869         hdr.Flags = TCP_FLAG_SYN;
 870         hdr.WindowSize = htons(TCP_WINDOW_SIZE);        // Max
 871         hdr.Checksum = 0;       // TODO
 872
 873         TCP_SendPacket( Conn, sizeof(tTCPHeader), &hdr );
 874
 875         Conn->NextSequenceSend ++;
 876         Conn->State = TCP_ST_SYN_SENT;
 877         return ;
 878 }
 879
 880 /**
 881  * \brief Control a client socket
 882  */
 883 int TCP_Client_IOCtl(tVFS_Node *Node, int ID, void *Data)
 884 {
 885         tTCPConnection  *conn = Node->ImplPtr;
 886
 887         ENTER("pNode iID pData", Node, ID, Data);
 888
 889         switch(ID)
 890         {
 891         case 4: // Get/Set local port
 892                 if(!Data)
 893                         LEAVE_RET('i', conn->LocalPort);
 894                 if(conn->State != TCP_ST_CLOSED)
 895                         LEAVE_RET('i', -1);
 896                 if(!CheckMem(Data, sizeof(Uint16)))
 897                         LEAVE_RET('i', -1);
 898
 899                 if(Threads_GetUID() != 0 && *(Uint16*)Data < 1024)
 900                         LEAVE_RET('i', -1);
 901
 902                 conn->LocalPort = *(Uint16*)Data;
 903                 LEAVE_RET('i', conn->LocalPort);
 904
 905         case 5: // Get/Set remote port
 906                 if(!Data)       LEAVE_RET('i', conn->RemotePort);
 907                 if(conn->State != TCP_ST_CLOSED)        LEAVE_RET('i', -1);
 908                 if(!CheckMem(Data, sizeof(Uint16)))     LEAVE_RET('i', -1);
 909                 conn->RemotePort = *(Uint16*)Data;
 910                 LEAVE_RET('i', conn->RemotePort);
 911
 912         case 6: // Set Remote IP
 913                 if( conn->State != TCP_ST_CLOSED )
 914                         LEAVE_RET('i', -1);
 915                 if( conn->Interface->Type == 4 )
 916                 {
 917                         if(!CheckMem(Data, sizeof(tIPv4)))      LEAVE_RET('i', -1);
 918                         conn->RemoteIP.v4 = *(tIPv4*)Data;
 919                 }
 920                 else if( conn->Interface->Type == 6 )
 921                 {
 922                         if(!CheckMem(Data, sizeof(tIPv6)))      LEAVE_RET('i', -1);
 923                         conn->RemoteIP.v6 = *(tIPv6*)Data;
 924                 }
 925                 LEAVE_RET('i', 0);
 926
 927         case 7: // Connect
 928                 if(conn->LocalPort == 0xFFFF)
 929                         conn->LocalPort = TCP_GetUnusedPort();
 930                 if(conn->RemotePort == -1)
 931                         LEAVE_RET('i', 0);
 932
 933                 TCP_StartConnection(conn);
 934                 LEAVE_RET('i', 1);
 935
 936         // Get recieve buffer length
 937         case 8:
 938                 LEAVE_RET('i', conn->RecievedBuffer->Length);
 939         }
 940
 941         return 0;
 942 }
 943
 944 void TCP_Client_Close(tVFS_Node *Node)
 945 {
 946         tTCPConnection  *conn = Node->ImplPtr;
 947         tTCPHeader      packet;
 948
 949         ENTER("pNode", Node);
 950
 951         packet.SourcePort = htons(conn->LocalPort);
 952         packet.DestPort = htons(conn->RemotePort);
 953         packet.DataOffset = (sizeof(tTCPHeader)/4)*16;
 954         packet.WindowSize = TCP_WINDOW_SIZE;
 955
 956         packet.AcknowlegementNumber = 0;
 957         packet.SequenceNumber = htonl(conn->NextSequenceSend);
 958         packet.Flags = TCP_FLAG_FIN;
 959
 960         conn->State = TCP_ST_FIN_SENT;
 961
 962         TCP_SendPacket( conn, sizeof(tTCPHeader), &packet );
 963
 964         while( conn->State == TCP_ST_FIN_SENT ) Threads_Yield();
 965
 966         free(conn);
 967
 968         LEAVE('-');
 969 }