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 <string.h>
  10 #include <SDL/SDL.h>
  11 #ifdef __WIN32__
  12 # include <windows.h>
  13 # include <winsock.h>
  14 #else
  15 # include <unistd.h>
  16 # include <sys/socket.h>
  17 # include <netinet/in.h>
  18 # include <arpa/inet.h> // inet_ntop
  19 #endif
  20 #include "../syscalls.h"
  21 //#include <debug.h>
  22
  23 #define USE_TCP 1
  24 #define MAX_CLIENTS     16
  25
  26 // === TYPES ===
  27 typedef struct {
  28          int    ClientID;
  29         SDL_Thread      *WorkerThread;
  30         #if USE_TCP
  31          int    Socket;
  32         #else
  33         tRequestHeader  *CurrentRequest;
  34         struct sockaddr_in      ClientAddr;
  35         SDL_cond        *WaitFlag;
  36         SDL_mutex       *Mutex;
  37         #endif
  38 }       tClient;
  39
  40 // === IMPORTS ===
  41 extern tRequestHeader *SyscallRecieve(tRequestHeader *Request, int *ReturnLength);
  42 extern int      Threads_CreateRootProcess(void);
  43 extern void     Threads_SetThread(int TID);
  44 // HACK: Should have these in a header
  45 extern void     Log_Debug(const char *Subsys, const char *Message, ...);
  46 extern void     Log_Notice(const char *Subsys, const char *Message, ...);
  47 extern void     Log_Warning(const char *Subsys, const char *Message, ...);
  48
  49 // === PROTOTYPES ===
  50 tClient *Server_GetClient(int ClientID);
  51  int    Server_WorkerThread(void *ClientPtr);
  52  int    SyscallServer(void);
  53  int    Server_ListenThread(void *Unused);
  54
  55 // === GLOBALS ===
  56 #ifdef __WIN32__
  57 WSADATA gWinsock;
  58 SOCKET  gSocket = INVALID_SOCKET;
  59 #else
  60 # define INVALID_SOCKET -1
  61  int    gSocket = INVALID_SOCKET;
  62 #endif
  63 tClient gaServer_Clients[MAX_CLIENTS];
  64 SDL_Thread      *gpServer_ListenThread;
  65
  66 // === CODE ===
  67 int Server_GetClientID(void)
  68 {
  69          int    i;
  70         Uint32  thisId = SDL_ThreadID();
  71
  72         for( i = 0; i < MAX_CLIENTS; i ++ )
  73         {
  74                 if( SDL_GetThreadID(gaServer_Clients[i].WorkerThread) == thisId )
  75                         return gaServer_Clients[i].ClientID;
  76         }
  77
  78         fprintf(stderr, "ERROR: Server_GetClientID - Thread is not allocated\n");
  79
  80         return 0;
  81 }
  82
  83 tClient *Server_GetClient(int ClientID)
  84 {
  85         tClient *ret = NULL;
  86          int    i;
  87
  88         // Allocate an ID if needed
  89         if(ClientID == 0)
  90                 ClientID = Threads_CreateRootProcess();
  91
  92         for( i = 0; i < MAX_CLIENTS; i ++ )
  93         {
  94                 if( gaServer_Clients[i].ClientID == ClientID ) {
  95                         return &gaServer_Clients[i];
  96                 }
  97                 if(!ret && gaServer_Clients[i].ClientID == 0)
  98                         ret = &gaServer_Clients[i];
  99         }
 100
 101         // Uh oh, no free slots
 102         // TODO: Dynamic allocation
 103         if( !ret )
 104                 return NULL;
 105
 106         // Allocate a thread for the process
 107         ret->ClientID = ClientID;
 108         #if USE_TCP
 109         ret->Socket = 0;
 110         #else
 111         ret->CurrentRequest = NULL;
 112         #endif
 113
 114         if( !ret->WorkerThread ) {
 115                 #if USE_TCP
 116                 #else
 117                 ret->WaitFlag = SDL_CreateCond();
 118                 ret->Mutex = SDL_CreateMutex();
 119                 SDL_mutexP( ret->Mutex );
 120                 #endif
 121                 ret->WorkerThread = SDL_CreateThread( Server_WorkerThread, ret );
 122         }
 123
 124         return ret;
 125 }
 126
 127 int Server_WorkerThread(void *ClientPtr)
 128 {
 129         tClient *Client = ClientPtr;
 130
 131         #if USE_TCP
 132         for( ;; )
 133         {
 134                 fd_set  fds;
 135                  int    nfd = Client->Socket;
 136                 FD_ZERO(&fds);
 137                 FD_SET(Client->Socket, &fds);
 138
 139                 select(nfd, &fds, NULL, NULL, NULL);    // TODO: Timeouts?
 140
 141                 if( FD_ISSET(Client->Socket, &fds) )
 142                 {
 143                         const int       ciMaxParamCount = 6;
 144                         char    lbuf[sizeof(tRequestHeader) + ciMaxParamCount*sizeof(tRequestValue)];
 145                         tRequestHeader  *hdr = (void*)lbuf;
 146                         size_t  len = recv(Client->Socket, hdr, sizeof(*hdr), 0);
 147                         if( len != sizeof(hdr) ) {
 148                                 // Oops?
 149                         }
 150
 151                         if( hdr->NParams > ciMaxParamCount ) {
 152                                 // Oops.
 153                         }
 154
 155                         len = recv(Client->Socket, hdr->Params, hdr->NParams*sizeof(tRequestValue), 0);
 156                         if( len != hdr->NParams*sizeof(tRequestValue) ) {
 157                                 // Oops.
 158                         }
 159
 160                         // Get buffer size
 161                         size_t  hdrsize = sizeof(tRequestHeader) + hdr->NParams*sizeof(tRequestValue);
 162                         size_t  bufsize = hdrsize;
 163                          int    i;
 164                         for( i = 0; i < hdr->NParams; i ++ )
 165                         {
 166                                 if( hdr->Params[i].Flags & ARG_FLAG_ZEROED )
 167                                         ;
 168                                 else {
 169                                         bufsize += hdr->Params[i].Length;
 170                                 }
 171                         }
 172
 173                         // Allocate full buffer
 174                         hdr = malloc(bufsize);
 175                         memcpy(hdr, lbuf, hdrsize);
 176                         len = recv(Client->Socket, hdr->Params + hdr->NParams, bufsize - hdrsize, 0);
 177                         if( len != bufsize - hdrsize ) {
 178                                 // Oops?
 179                         }
 180
 181                          int    retlen;
 182                         tRequestHeader  *retHeader;
 183                         retHeader = SyscallRecieve(hdr, &retlen);
 184                         if( !retHeader ) {
 185                                 // Some sort of error
 186                         }
 187
 188                         send(Client->Socket, retHeader, retlen, 0);
 189
 190                         // Clean up
 191                         free(hdr);
 192                 }
 193         }
 194         #else
 195         tRequestHeader  *retHeader;
 196         tRequestHeader  errorHeader;
 197          int    retSize = 0;
 198          int    sentSize;
 199          int    cur_client_id = 0;
 200         for( ;; )
 201         {
 202                 // Wait for something to do
 203                 while( Client->CurrentRequest == NULL )
 204                         SDL_CondWait(Client->WaitFlag, Client->Mutex);
 205
 206 //              Log_Debug("AcessSrv", "Worker got message %p", Client->CurrentRequest);
 207
 208                 if(Client->ClientID != cur_client_id) {
 209 //                      Log_Debug("AcessSrv", "Client thread ID changed from %i to %i",
 210 //                              cur_client_id, Client->ClientID);
 211                         Threads_SetThread( Client->ClientID );
 212                         cur_client_id = Client->ClientID;
 213                 }
 214
 215                 // Debug
 216                 {
 217                         int     callid = Client->CurrentRequest->CallID;
 218                         Log_Debug("AcessSrv", "Client %i request %i %s",
 219                                 Client->ClientID, callid,
 220                                 callid < N_SYSCALLS ? casSYSCALL_NAMES[callid] : "UNK"
 221                                 );
 222                 }
 223
 224                 // Get the response
 225                 retHeader = SyscallRecieve(Client->CurrentRequest, &retSize);
 226
 227                 if( !retHeader ) {
 228                         // Return an error to the client
 229                         printf("ERROR: SyscallRecieve failed\n");
 230                         errorHeader.CallID = Client->CurrentRequest->CallID;
 231                         errorHeader.NParams = 0;
 232                         retHeader = &errorHeader;
 233                         retSize = sizeof(errorHeader);
 234                 }
 235
 236                 // Set ID
 237                 retHeader->ClientID = Client->ClientID;
 238
 239                 // Mark the thread as ready for another job
 240                 free(Client->CurrentRequest);
 241                 Client->CurrentRequest = 0;
 242
 243 //              Log_Debug("AcessSrv", "Sending %i to %x:%i (Client %i)",
 244 //                      retSize, ntohl(Client->ClientAddr.sin_addr.s_addr),
 245 //                      ntohs(Client->ClientAddr.sin_port),
 246 //                      Client->ClientID
 247 //                      );
 248
 249                 // Return the data
 250                 sentSize = sendto(gSocket, retHeader, retSize, 0,
 251                         (struct sockaddr*)&Client->ClientAddr, sizeof(Client->ClientAddr)
 252                         );
 253                 if( sentSize != retSize ) {
 254                         perror("Server_WorkerThread - send");
 255                 }
 256
 257                 // Free allocated header
 258                 if( retHeader != &errorHeader )
 259                         free( retHeader );
 260         }
 261         #endif
 262 }
 263
 264 int SyscallServer(void)
 265 {
 266         struct sockaddr_in      server;
 267
 268         #ifdef __WIN32__
 269         /* Open windows connection */
 270         if (WSAStartup(0x0101, &gWinsock) != 0)
 271         {
 272                 fprintf(stderr, "Could not open Windows connection.\n");
 273                 exit(0);
 274         }
 275         #endif
 276
 277         #if USE_TCP
 278         // Open TCP Connection
 279         gSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
 280         #else
 281         // Open UDP Connection
 282         gSocket = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
 283         #endif
 284         if (gSocket == INVALID_SOCKET)
 285         {
 286                 fprintf(stderr, "Could not create socket.\n");
 287                 #if __WIN32__
 288                 WSACleanup();
 289                 #endif
 290                 exit(0);
 291         }
 292
 293         // Set server address
 294         memset(&server, 0, sizeof(struct sockaddr_in));
 295         server.sin_family = AF_INET;
 296         server.sin_port = htons(SERVER_PORT);
 297         server.sin_addr.s_addr = htonl(INADDR_ANY);
 298
 299         // Bind
 300         if( bind(gSocket, (struct sockaddr *)&server, sizeof(struct sockaddr_in)) == -1 )
 301         {
 302                 fprintf(stderr, "Cannot bind address to socket.\n");
 303                 perror("SyscallServer - bind");
 304                 #if __WIN32__
 305                 closesocket(gSocket);
 306                 WSACleanup();
 307                 #else
 308                 close(gSocket);
 309                 #endif
 310                 exit(0);
 311         }
 312
 313         #if USE_TCP
 314         listen(gSocket, 5);
 315         #endif
 316
 317         Log_Notice("AcessSrv", "Listening on 0.0.0.0:%i", SERVER_PORT);
 318         gpServer_ListenThread = SDL_CreateThread( Server_ListenThread, NULL );
 319         return 0;
 320 }
 321
 322 int Server_ListenThread(void *Unused)
 323 {
 324         // Wait for something to do :)
 325         for( ;; )
 326         {
 327                 #if USE_TCP
 328                 struct sockaddr_in      clientaddr;
 329                 socklen_t       clientSize = sizeof(clientaddr);
 330                  int    clientSock = accept(gSocket, (struct sockaddr*)&clientaddr, &clientSize);
 331                 if( clientSock < 0 ) {
 332                         perror("SyscallServer - accept");
 333                         break ;
 334                 }
 335
 336                 char    addrstr[4*8+8+1];
 337                 inet_ntop(clientaddr.sin_family, &clientaddr.sin_addr, addrstr, sizeof(addrstr));
 338                 Log_Debug("Server", "Client connection %s:%i\n", addrstr, ntohs(clientaddr.sin_port));
 339
 340                 // Perform auth
 341                 size_t  len;
 342                 tRequestAuthHdr authhdr;
 343                 len = recv(clientSock, &authhdr, sizeof(authhdr), 0);
 344                 if( len != sizeof(authhdr) ) {
 345                         // Some form of error?
 346                 }
 347
 348                 tClient *client;
 349                 if( authhdr.pid == 0 ) {
 350                         // Allocate PID and client structure/thread
 351                         client = Server_GetClient(0);
 352                         client->Socket = clientSock;
 353                         authhdr.pid = client->ClientID;
 354                 }
 355                 else {
 356                         // Get client structure and make sure it's unused
 357                         // - Auth token / verifcation?
 358                         client = Server_GetClient(authhdr.pid);
 359                         if( client->Socket != 0 ) {
 360                                 Log_Warning("Server", "Client (%i)%p owned by FD%i but %s:%i tried to use it",
 361                                         authhdr.pid, client, addrstr, clientaddr.sin_port);
 362                                 authhdr.pid = 0;
 363                         }
 364                         else {
 365                                 client->Socket = clientSock;
 366                         }
 367                 }
 368
 369                 len = send(clientSock, &authhdr, sizeof(authhdr), 0);
 370                 if( len != sizeof(authhdr) ) {
 371                         // Ok, this is an error
 372                         perror("Sending auth reply");
 373                 }
 374
 375                 // All done, client thread should be watching now
 376
 377                 #else
 378                 char    data[BUFSIZ];
 379                 tRequestHeader  *req = (void*)data;
 380                 struct sockaddr_in      addr;
 381                 uint    clientSize = sizeof(addr);
 382                  int    length;
 383                 tClient *client;
 384
 385                 length = recvfrom(gSocket, data, BUFSIZ, 0, (struct sockaddr*)&addr, &clientSize);
 386
 387                 if( length == -1 ) {
 388                         perror("SyscallServer - recv");
 389                         break;
 390                 }
 391
 392                 // Hand off to a worker thread
 393                 // - TODO: Actually have worker threads
 394 //              Log_Debug("Server", "%i bytes from %x:%i", length,
 395 //                      ntohl(addr.sin_addr.s_addr), ntohs(addr.sin_port));
 396
 397                 client = Server_GetClient(req->ClientID);
 398                 // NOTE: Hack - Should check if all zero
 399                 if( req->ClientID == 0 || client->ClientAddr.sin_port == 0 )
 400                 {
 401                         memcpy(&client->ClientAddr, &addr, sizeof(addr));
 402                 }
 403                 else if( memcmp(&client->ClientAddr, &addr, sizeof(addr)) != 0 )
 404                 {
 405                         printf("ClientID %i used by %x:%i\n",
 406                                 client->ClientID, ntohl(addr.sin_addr.s_addr), ntohs(addr.sin_port));
 407                         printf(" actually owned by %x:%i\n",
 408                                 ntohl(client->ClientAddr.sin_addr.s_addr), ntohs(client->ClientAddr.sin_port));
 409                         continue;
 410                 }
 411
 412                 if( client->CurrentRequest ) {
 413                         printf("Worker thread for %x:%i is busy\n",
 414                                 ntohl(client->ClientAddr.sin_addr.s_addr), ntohs(client->ClientAddr.sin_port));
 415                         continue;
 416                 }
 417
 418 //              Log_Debug("AcessSrv", "Message from Client %i (%p)",
 419 //                      client->ClientID, client);
 420
 421                 // Make a copy of the request data
 422                 req = malloc(length);
 423                 memcpy(req, data, length);
 424                 client->CurrentRequest = req;
 425                 SDL_CondSignal(client->WaitFlag);
 426                 #endif
 427         }
 428         return -1;
 429 }