AcessNative/acesskernel_src/server.c

   1 /*
   2  * Acess2 Native Kernel
   3  * - Acess kernel emulation on another OS using SDL and UDP
   4  *
   5  * Syscall Server
   6  */
   7 #include <stdio.h>
   8 #include <stdlib.h>
   9 #include <stdbool.h>
  10 #include <string.h>
  11 #include <SDL/SDL.h>
  12 #ifdef __WIN32__
  13 # define _WIN32_WINNT 0x0501
  14 # include <windows.h>
  15 # include <winsock2.h>
  16 # include <ws2tcpip.h>
  17 # define close(fd)      closesocket(fd)
  18 typedef int     socklen_t;
  19 #else
  20 # include <unistd.h>
  21 # include <sys/socket.h>
  22 # include <netinet/in.h>
  23 # include <netdb.h>     // getaddrinfo
  24 #endif
  25 #define DONT_INCLUDE_SYSCALL_NAMES
  26 #include "../syscalls.h"
  27 #include <logdebug.h>   // acess but std
  28 #include <errno.h>
  29
  30 #define USE_TCP 1
  31 #define MAX_CLIENTS     16
  32
  33 // === TYPES ===
  34 typedef struct {
  35          int    ClientID;
  36         SDL_Thread      *WorkerThread;
  37         tRequestHeader  *CurrentRequest;
  38         SDL_cond        *WaitFlag;
  39         SDL_mutex       *Mutex;
  40         #if USE_TCP
  41          int    Socket;
  42         #else
  43         struct sockaddr_in      ClientAddr;
  44         #endif
  45 }       tClient;
  46
  47 // === IMPORTS ===
  48 // TODO: Move these to headers
  49 extern tRequestHeader *SyscallRecieve(tRequestHeader *Request, size_t *ReturnLength);
  50 extern int      Threads_CreateRootProcess(void);
  51 extern void     Threads_SetThread(int TID, void *ClientPtr);
  52 extern void     *Threads_GetThread(int TID);
  53 extern void     Threads_PostEvent(void *Thread, uint32_t Event);
  54 extern void     Threads_int_Terminate(void *Thread);
  55
  56 // === PROTOTYPES ===
  57 tClient *Server_GetClient(int ClientID);
  58  int    Server_WorkerThread(void *ClientPtr);
  59  int    SyscallServer(void);
  60  int    Server_ListenThread(void *Unused);
  61
  62 // === GLOBALS ===
  63 #ifdef __WIN32__
  64 WSADATA gWinsock;
  65 SOCKET  gSocket = INVALID_SOCKET;
  66 #else
  67 # define INVALID_SOCKET -1
  68  int    gSocket = INVALID_SOCKET;
  69 #endif
  70 tClient gaServer_Clients[MAX_CLIENTS];
  71 SDL_Thread      *gpServer_ListenThread;
  72
  73 // === CODE ===
  74 int Server_GetClientID(void)
  75 {
  76         Uint32  thisId = SDL_ThreadID();
  77
  78         for( int i = 0; i < MAX_CLIENTS; i ++ )
  79         {
  80                 if( SDL_GetThreadID(gaServer_Clients[i].WorkerThread) == thisId )
  81                         return gaServer_Clients[i].ClientID;
  82         }
  83
  84         fprintf(stderr, "ERROR: Server_GetClientID - Thread is not allocated\n");
  85
  86         return 0;
  87 }
  88
  89 tClient *Server_GetClient(int ClientID)
  90 {
  91         tClient *ret = NULL;
  92
  93         // Allocate an ID if needed
  94         if(ClientID == 0)
  95                 ClientID = Threads_CreateRootProcess();
  96
  97         for( int i = 0; i < MAX_CLIENTS; i ++ )
  98         {
  99                 if( gaServer_Clients[i].ClientID == ClientID ) {
 100                         return &gaServer_Clients[i];
 101                 }
 102                 if(!ret && gaServer_Clients[i].ClientID == 0)
 103                         ret = &gaServer_Clients[i];
 104         }
 105
 106         // Uh oh, no free slots
 107         // TODO: Dynamic allocation
 108         if( !ret ) {
 109                 Log_Error("Server", "Ran out of static client slots (%i)", MAX_CLIENTS);
 110                 return NULL;
 111         }
 112
 113         // Allocate a thread for the process
 114         ret->ClientID = ClientID;
 115         ret->CurrentRequest = NULL;
 116         #if USE_TCP
 117         ret->Socket = 0;
 118         #endif
 119
 120         if( !ret->WorkerThread ) {
 121                 Log_Debug("Server", "Creating worker for %p", ret);
 122                 ret->WaitFlag = SDL_CreateCond();
 123                 ret->Mutex = SDL_CreateMutex();
 124                 SDL_mutexP( ret->Mutex );
 125                 ret->WorkerThread = SDL_CreateThread( Server_WorkerThread, ret );
 126         }
 127
 128         return ret;
 129 }
 130
 131 int Server_WorkerThread(void *ClientPtr)
 132 {
 133         tClient *Client = ClientPtr;
 134
 135         Log_Debug("Server", "Worker %p active", ClientPtr);
 136
 137         tRequestHeader  errorHeader;
 138         size_t  retSize = 0;
 139          int    cur_client_id = 0;
 140         while( Client->ClientID != 0 )
 141         {
 142                 // Wait for something to do
 143                 if( Client->CurrentRequest == NULL )
 144                         SDL_CondWait(Client->WaitFlag, Client->Mutex);
 145                 if( Client->CurrentRequest == NULL )
 146                         continue ;
 147
 148                 if(Client->ClientID != cur_client_id) {
 149                         Threads_SetThread( Client->ClientID, Client );
 150                         cur_client_id = Client->ClientID;
 151                 }
 152
 153                 // Get the response
 154                 tRequestHeader  *retHeader = SyscallRecieve(Client->CurrentRequest, &retSize);
 155
 156                 if( !retHeader ) {
 157                         // Return an error to the client
 158                         printf("ERROR: SyscallRecieve failed\n");
 159                         errorHeader.CallID = Client->CurrentRequest->CallID;
 160                         errorHeader.NParams = 0;
 161                         retHeader = &errorHeader;
 162                         retSize = sizeof(errorHeader);
 163                 }
 164
 165                 // Set ID
 166                 retHeader->ClientID = Client->ClientID;
 167
 168                 // Mark the thread as ready for another job
 169                 free(Client->CurrentRequest);
 170                 Client->CurrentRequest = 0;
 171
 172                 // If the thread is being terminated, don't send reply
 173                 if( Client->ClientID > 0 )
 174                 {
 175                         // Return the data
 176                         #if USE_TCP
 177                         size_t sentSize = send(Client->Socket, retHeader, retSize, 0);
 178                         #else
 179                         size_t sentSize = sendto(gSocket, retHeader, retSize, 0,
 180                                 (struct sockaddr*)&Client->ClientAddr, sizeof(Client->ClientAddr)
 181                                 );
 182                         #endif
 183                         if( sentSize != retSize ) {
 184                                 perror("Server_WorkerThread - send");
 185                         }
 186                 }
 187
 188                 // Free allocated header
 189                 if( retHeader != &errorHeader )
 190                         free( retHeader );
 191         }
 192         Log_Notice("Server", "Terminated Worker %p", ClientPtr);
 193         return 0;
 194 }
 195
 196 int SyscallServer(void)
 197 {
 198         struct sockaddr_in      server;
 199
 200         #ifdef __WIN32__
 201         /* Open windows connection */
 202         if (WSAStartup(0x0101, &gWinsock) != 0)
 203         {
 204                 fprintf(stderr, "Could not open Windows connection.\n");
 205                 exit(0);
 206         }
 207         #endif
 208
 209         #if USE_TCP
 210         // Open TCP Connection
 211         gSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
 212         #else
 213         // Open UDP Connection
 214         gSocket = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
 215         #endif
 216         if (gSocket == INVALID_SOCKET)
 217         {
 218                 fprintf(stderr, "Could not create socket.\n");
 219                 #if __WIN32__
 220                 WSACleanup();
 221                 #endif
 222                 exit(0);
 223         }
 224
 225         // Set server address
 226         memset(&server, 0, sizeof(struct sockaddr_in));
 227         server.sin_family = AF_INET;
 228         server.sin_port = htons(SERVER_PORT);
 229         server.sin_addr.s_addr = htonl(INADDR_ANY);
 230
 231         // Bind
 232         if( bind(gSocket, (struct sockaddr *)&server, sizeof(struct sockaddr_in)) == -1 )
 233         {
 234                 fprintf(stderr, "Cannot bind address to socket.\n");
 235                 perror("SyscallServer - bind");
 236                 #if __WIN32__
 237                 closesocket(gSocket);
 238                 WSACleanup();
 239                 #else
 240                 close(gSocket);
 241                 #endif
 242                 exit(0);
 243         }
 244
 245         #if USE_TCP
 246         listen(gSocket, 5);
 247         #endif
 248
 249         Log_Notice("AcessSrv", "Listening on 0.0.0.0:%i", SERVER_PORT);
 250         gpServer_ListenThread = SDL_CreateThread( Server_ListenThread, NULL );
 251         return 0;
 252 }
 253
 254 int Server_Shutdown(void)
 255 {
 256         close(gSocket);
 257         for( int i = 0; i < MAX_CLIENTS; i ++ )
 258         {
 259                 if( gaServer_Clients[i].ClientID == 0 )
 260                         continue ;
 261                 Threads_PostEvent( Threads_GetThread(gaServer_Clients[i].ClientID), 0 );
 262                 gaServer_Clients[i].ClientID = -1;
 263                 #if USE_TCP
 264                 close(gaServer_Clients[i].Socket);
 265                 #else
 266                 SDL_CondSignal(gaServer_Clients[i].WaitFlag);
 267                 #endif
 268         }
 269         return 0;
 270 }
 271
 272 #if USE_TCP
 273 int Server_int_HandleRx(tClient *Client)
 274 {
 275         const int       ciMaxParamCount = 6;
 276         char    lbuf[sizeof(tRequestHeader) + ciMaxParamCount*sizeof(tRequestValue)];
 277         tRequestHeader  *hdr = (void*)lbuf;
 278         size_t  len = recv(Client->Socket, (void*)hdr, sizeof(*hdr), 0);
 279         if( len == 0 ) {
 280                 Log_Notice("Server", "Zero RX on %i (worker %p)", Client->Socket, Client);
 281                 return 1;
 282         }
 283         if( len == -1 ) {
 284                 perror("recv header");
 285                 return 2;
 286         }
 287         if( len != sizeof(*hdr) ) {
 288                 // Oops?
 289                 Log_Warning("Server", "FD%i bad sized (%i != exp %i)",
 290                         Client->Socket, len, sizeof(*hdr));
 291                 return 0;
 292         }
 293
 294         if( hdr->NParams > ciMaxParamCount ) {
 295                 // Oops.
 296                 Log_Warning("Server", "FD%i too many params (%i > max %i)",
 297                         Client->Socket, hdr->NParams, ciMaxParamCount);
 298                 return 0;
 299         }
 300
 301         if( hdr->NParams > 0 )
 302         {
 303                 len = recv(Client->Socket, (void*)hdr->Params, hdr->NParams*sizeof(tRequestValue), 0);
 304                 if( len != hdr->NParams*sizeof(tRequestValue) ) {
 305                         // Oops.
 306                         perror("recv params");
 307                         Log_Warning("Sever", "Recieving params failed");
 308                         return 0;
 309                 }
 310         }
 311         else
 312         {
 313                 //Log_Debug("Server", "No params?");
 314         }
 315
 316         // Get buffer size
 317         size_t  hdrsize = sizeof(tRequestHeader) + hdr->NParams*sizeof(tRequestValue);
 318         size_t  bufsize = hdrsize;
 319         for( int i = 0; i < hdr->NParams; i ++ )
 320         {
 321                 if( hdr->Params[i].Flags & ARG_FLAG_ZEROED )
 322                         ;
 323                 else {
 324                         bufsize += hdr->Params[i].Length;
 325                 }
 326         }
 327
 328         // Allocate full buffer
 329         hdr = malloc(bufsize);
 330         memcpy(hdr, lbuf, hdrsize);
 331         if( bufsize > hdrsize )
 332         {
 333                 size_t  rem = bufsize - hdrsize;
 334                 char    *ptr = (void*)( hdr->Params + hdr->NParams );
 335                 while( rem )
 336                 {
 337                         len = recv(Client->Socket, ptr, rem, 0);
 338                         if( len == -1 ) {
 339                                 // Oops?
 340                                 perror("recv data");
 341                                 Log_Warning("Sever", "Recieving data failed");
 342                                 return 2;
 343                         }
 344                         rem -= len;
 345                         ptr += len;
 346                 }
 347                 if( rem ) {
 348                         // Extra data?
 349                         return 0;
 350                 }
 351         }
 352         else {
 353                 //Log_Debug("Server", "no data");
 354         }
 355
 356         // Dispatch to worker
 357         if( Client->CurrentRequest ) {
 358                 printf("Worker thread for client ID %i is busy\n", Client->ClientID);
 359                 return 1;
 360         }
 361
 362         // Give to worker
 363         Log_Debug("Server", "Message from Client %i (%p)", Client->ClientID, Client);
 364         Client->CurrentRequest = hdr;
 365         SDL_CondSignal(Client->WaitFlag);
 366
 367         return 0;
 368 }
 369
 370 int Server_int_HandshakeClient(int Socket, struct sockaddr_in *addr, socklen_t addr_size)
 371 {
 372         ENTER("iSocket paddr iaddr_size",
 373                 Socket, addr, addr_size);
 374         unsigned short  port = ntohs(addr->sin_port);
 375         char    addrstr[4*8+8+1];
 376         getnameinfo((struct sockaddr*)addr, addr_size, addrstr, sizeof(addrstr), NULL, 0, NI_NUMERICHOST);
 377         Log_Debug("Server", "Client connection %s:%i", addrstr, port);
 378
 379         // Perform handshake
 380         tRequestAuthHdr authhdr;
 381         size_t  len  = recv(Socket, &authhdr, sizeof(authhdr), 0);
 382         if( len != sizeof(authhdr) ) {
 383                 // Some form of error?
 384                 Log_Warning("Server", "Client auth block bad size (%i != exp %i)",
 385                         len, sizeof(authhdr));
 386                 LEAVE('i', 1);
 387                 return 1;
 388         }
 389
 390         LOG("authhdr.pid = %i", authhdr.pid);
 391         tClient *client = Server_GetClient(authhdr.pid);
 392         if( authhdr.pid == 0 ) {
 393                 // Allocate PID and client structure/thread
 394                 client->Socket = Socket;
 395                 authhdr.pid = client->ClientID;
 396         }
 397         else {
 398                 Log_Debug("Server", "Client assumed PID %i", authhdr.pid);
 399
 400                 // Get client structure and make sure it's unused
 401                 // - Auth token / verifcation?
 402                 if( !client ) {
 403                         Log_Warning("Server", "Can't allocate a client struct for %s:%i",
 404                                 addrstr, port);
 405                         LEAVE('i', 1);
 406                         return 1;
 407                 }
 408                 if( client->Socket != 0 ) {
 409                         Log_Warning("Server", "Client (%i)%p owned by FD%i but %s:%i tried to use it",
 410                                 authhdr.pid, client, addrstr, port);
 411                         LEAVE('i', 1);
 412                         return 1;
 413                 }
 414
 415                 client->Socket = Socket;
 416         }
 417
 418         LOG("Sending auth reply");
 419         len = send(Socket, (void*)&authhdr, sizeof(authhdr), 0);
 420         if( len != sizeof(authhdr) ) {
 421                 // Ok, this is an error
 422                 perror("Sending auth reply");
 423                 LEAVE('i', 1);
 424                 return 1;
 425         }
 426
 427         // All done, client thread should be watching now
 428
 429         LEAVE('i', 0);
 430         return 0;
 431 }
 432
 433 void Server_int_RemoveClient(tClient *Client)
 434 {
 435         // Trigger the thread to kill itself
 436         Threads_int_Terminate( Threads_GetThread(Client->ClientID) );
 437         Client->ClientID = 0;
 438         close(Client->Socket);
 439 }
 440
 441 #endif
 442
 443 int Server_ListenThread(void *Unused)
 444 {
 445         // Wait for something to do :)
 446         for( ;; )
 447         {
 448                 #if USE_TCP
 449                 fd_set  fds;
 450                  int    maxfd = gSocket;
 451                 FD_ZERO(&fds);
 452                 FD_SET(gSocket, &fds);
 453
 454                 for( int i = 0; i < MAX_CLIENTS; i ++ ) {
 455                         tClient *client = &gaServer_Clients[i];
 456                         if( client->ClientID == 0 )
 457                                 continue ;
 458                         FD_SET(client->Socket, &fds);
 459                         if(client->Socket > maxfd)
 460                                 maxfd = client->Socket;
 461                 }
 462
 463                 int rv = select(maxfd+1, &fds, NULL, NULL, NULL);
 464                 Log_Debug("Server", "Select rv = %i", rv);
 465                 if( rv <= 0 ) {
 466                         perror("select");
 467                         return 1;
 468                 }
 469
 470                 // Incoming connection
 471                 if( FD_ISSET(gSocket, &fds) )
 472                 {
 473                         struct sockaddr_in      clientaddr;
 474                         socklen_t       clientSize = sizeof(clientaddr);
 475                          int    clientSock = accept(gSocket, (struct sockaddr*)&clientaddr, &clientSize);
 476                         if( clientSock < 0 ) {
 477                                 perror("SyscallServer - accept");
 478                                 break ;
 479                         }
 480                         if( Server_int_HandshakeClient(clientSock, &clientaddr, clientSize) ) {
 481                                 Log_Warning("Server", "Client handshake failed :(");
 482                                 close(clientSock);
 483                         }
 484                 }
 485
 486                 for( int i = 0; i < MAX_CLIENTS; i ++ )
 487                 {
 488                         tClient *client = &gaServer_Clients[i];
 489                         if( client->ClientID == 0 )
 490                                 continue ;
 491                         //Debug("Server_ListenThread: Idx %i ID %i FD %i",
 492                         //      i, client->ClientID, client->Socket);
 493                         if( !FD_ISSET(client->Socket, &fds) )
 494                                 continue ;
 495
 496                         if( Server_int_HandleRx( client ) )
 497                         {
 498                                 Log_Warning("Server", "Client %p dropped, TODO: clean up", client);
 499                                 Server_int_RemoveClient(client);
 500                         }
 501                 }
 502
 503                 #else
 504                 char    data[BUFSIZ];
 505                 tRequestHeader  *req = (void*)data;
 506                 struct sockaddr_in      addr;
 507                 uint    clientSize = sizeof(addr);
 508                  int    length;
 509
 510                 length = recvfrom(gSocket, data, BUFSIZ, 0, (struct sockaddr*)&addr, &clientSize);
 511
 512                 if( length == -1 ) {
 513                         perror("SyscallServer - recv");
 514                         break;
 515                 }
 516
 517                 // Recive data
 518 //              Log_Debug("Server", "%i bytes from %x:%i", length,
 519 //                      ntohl(addr.sin_addr.s_addr), ntohs(addr.sin_port));
 520
 521                 tClient *client = Server_GetClient(req->ClientID);
 522                 // NOTE: I should really check if the sin_addr is zero, but meh
 523                 // Shouldn't matter much
 524                 if( req->ClientID == 0 || client->ClientAddr.sin_port == 0 )
 525                 {
 526                         memcpy(&client->ClientAddr, &addr, sizeof(addr));
 527                 }
 528                 else if( memcmp(&client->ClientAddr, &addr, sizeof(addr)) != 0 )
 529                 {
 530                         printf("ClientID %i used by %x:%i\n",
 531                                 client->ClientID, ntohl(addr.sin_addr.s_addr), ntohs(addr.sin_port));
 532                         printf(" actually owned by %x:%i\n",
 533                                 ntohl(client->ClientAddr.sin_addr.s_addr), ntohs(client->ClientAddr.sin_port));
 534                         continue;
 535                 }
 536
 537 //              Log_Debug("AcessSrv", "Message from Client %i (%p)",
 538 //                      client->ClientID, client);
 539                 if( client->CurrentRequest ) {
 540                         printf("Worker thread for %x:%i is busy\n",
 541                                 ntohl(client->ClientAddr.sin_addr.s_addr), ntohs(client->ClientAddr.sin_port));
 542                         continue;
 543                 }
 544
 545                 // Duplicate the data currently on the stack, and dispatch to worker
 546                 req = malloc(length);
 547                 memcpy(req, data, length);
 548                 client->CurrentRequest = req;
 549                 SDL_CondSignal(client->WaitFlag);
 550                 #endif
 551         }
 552         return -1;
 553 }