server/request.c

   1 /*
   2  * Server-side request handling
   3  *
   4  * Copyright (C) 1998 Alexandre Julliard
   5  */
   6
   7 #include "config.h"
   8
   9 #include <assert.h>
  10 #include <errno.h>
  11 #include <fcntl.h>
  12 #include <pwd.h>
  13 #include <signal.h>
  14 #include <stdio.h>
  15 #include <stdlib.h>
  16 #include <stdarg.h>
  17 #include <string.h>
  18 #include <sys/stat.h>
  19 #include <sys/time.h>
  20 #include <sys/types.h>
  21 #ifdef HAVE_SYS_SOCKET_H
  22 # include <sys/socket.h>
  23 #endif
  24 #include <sys/uio.h>
  25 #include <sys/un.h>
  26 #include <unistd.h>
  27
  28 #include "winnt.h"
  29 #include "winbase.h"
  30 #include "wincon.h"
  31 #include "thread.h"
  32 #include "process.h"
  33 #include "server.h"
  34 #define WANT_REQUEST_HANDLERS
  35 #include "request.h"
  36 #include "wine/port.h"
  37
  38 /* Some versions of glibc don't define this */
  39 #ifndef SCM_RIGHTS
  40 #define SCM_RIGHTS 1
  41 #endif
  42
  43  /* path names for server master Unix socket */
  44 #define CONFDIR    "/.wine"        /* directory for Wine config relative to $HOME */
  45 #define SERVERDIR  "/wineserver-"  /* server socket directory (hostname appended) */
  46 #define SOCKETNAME "socket"        /* name of the socket file */
  47
  48 struct master_socket
  49 {
  50     struct object       obj;         /* object header */
  51 };
  52
  53 static void master_socket_dump( struct object *obj, int verbose );
  54 static void master_socket_poll_event( struct object *obj, int event );
  55 static void master_socket_destroy( struct object *obj );
  56
  57 static const struct object_ops master_socket_ops =
  58 {
  59     sizeof(struct master_socket),  /* size */
  60     master_socket_dump,            /* dump */
  61     no_add_queue,                  /* add_queue */
  62     NULL,                          /* remove_queue */
  63     NULL,                          /* signaled */
  64     NULL,                          /* satisfied */
  65     NULL,                          /* get_poll_events */
  66     master_socket_poll_event,      /* poll_event */
  67     no_get_fd,                     /* get_fd */
  68     no_flush,                      /* flush */
  69     no_get_file_info,              /* get_file_info */
  70     master_socket_destroy          /* destroy */
  71 };
  72
  73
  74 struct request_socket
  75 {
  76     struct object       obj;         /* object header */
  77     struct thread      *thread;      /* owning thread */
  78 };
  79
  80 static void request_socket_dump( struct object *obj, int verbose );
  81 static void request_socket_poll_event( struct object *obj, int event );
  82
  83 static const struct object_ops request_socket_ops =
  84 {
  85     sizeof(struct request_socket), /* size */
  86     request_socket_dump,           /* dump */
  87     no_add_queue,                  /* add_queue */
  88     NULL,                          /* remove_queue */
  89     NULL,                          /* signaled */
  90     NULL,                          /* satisfied */
  91     NULL,                          /* get_poll_events */
  92     request_socket_poll_event,     /* poll_event */
  93     no_get_fd,                     /* get_fd */
  94     no_flush,                      /* flush */
  95     no_get_file_info,              /* get_file_info */
  96     no_destroy                     /* destroy */
  97 };
  98
  99
 100 struct thread *current = NULL;  /* thread handling the current request */
 101 unsigned int global_error = 0;  /* global error code for when no thread is current */
 102
 103 static struct master_socket *master_socket;  /* the master socket object */
 104
 105 /* socket communication static structures */
 106 static struct iovec myiovec;
 107 static struct msghdr msghdr;
 108 #ifndef HAVE_MSGHDR_ACCRIGHTS
 109 struct cmsg_fd
 110 {
 111     int len;   /* sizeof structure */
 112     int level; /* SOL_SOCKET */
 113     int type;  /* SCM_RIGHTS */
 114     int fd;    /* fd to pass */
 115 };
 116 static struct cmsg_fd cmsg = { sizeof(cmsg), SOL_SOCKET, SCM_RIGHTS, -1 };
 117 #endif  /* HAVE_MSGHDR_ACCRIGHTS */
 118
 119 /* complain about a protocol error and terminate the client connection */
 120 void fatal_protocol_error( struct thread *thread, const char *err, ... )
 121 {
 122     va_list args;
 123
 124     va_start( args, err );
 125     fprintf( stderr, "Protocol error:%p: ", thread );
 126     vfprintf( stderr, err, args );
 127     va_end( args );
 128     thread->exit_code = 1;
 129     kill_thread( thread, 1 );
 130 }
 131
 132 /* complain about a protocol error and terminate the client connection */
 133 void fatal_protocol_perror( struct thread *thread, const char *err, ... )
 134 {
 135     va_list args;
 136
 137     va_start( args, err );
 138     fprintf( stderr, "Protocol error:%p: ", thread );
 139     vfprintf( stderr, err, args );
 140     perror( " " );
 141     va_end( args );
 142     thread->exit_code = 1;
 143     kill_thread( thread, 1 );
 144 }
 145
 146 /* die on a fatal error */
 147 void fatal_error( const char *err, ... )
 148 {
 149     va_list args;
 150
 151     va_start( args, err );
 152     fprintf( stderr, "wineserver: " );
 153     vfprintf( stderr, err, args );
 154     va_end( args );
 155     exit(1);
 156 }
 157
 158 /* die on a fatal error */
 159 void fatal_perror( const char *err, ... )
 160 {
 161     va_list args;
 162
 163     va_start( args, err );
 164     fprintf( stderr, "wineserver: " );
 165     vfprintf( stderr, err, args );
 166     perror( " " );
 167     va_end( args );
 168     exit(1);
 169 }
 170
 171 /* call a request handler */
 172 static inline void call_req_handler( struct thread *thread, union generic_request *request )
 173 {
 174     enum request req = request->header.req;
 175
 176     current = thread;
 177     clear_error();
 178
 179     if (debug_level) trace_request( thread, request );
 180
 181     if (request->header.var_size)
 182     {
 183         if ((unsigned int)request->header.var_offset +
 184                           request->header.var_size > MAX_REQUEST_LENGTH)
 185         {
 186             fatal_protocol_error( current, "bad request offset/size %d/%d\n",
 187                                   request->header.var_offset, request->header.var_size );
 188             return;
 189         }
 190     }
 191
 192     if (req < REQ_NB_REQUESTS)
 193     {
 194         req_handlers[req]( request );
 195         if (current) send_reply( current, request );
 196         current = NULL;
 197         return;
 198     }
 199     fatal_protocol_error( current, "bad request %d\n", req );
 200 }
 201
 202 /* send a reply to a thread */
 203 void send_reply( struct thread *thread, union generic_request *request )
 204 {
 205     int ret;
 206
 207     if (debug_level) trace_reply( thread, request );
 208
 209     request->header.error = thread->error;
 210
 211     if ((ret = write( thread->reply_fd, request, sizeof(*request) )) != sizeof(*request))
 212     {
 213         if (ret >= 0)
 214             fatal_protocol_error( thread, "partial write %d\n", ret );
 215         else if (errno == EPIPE)
 216             kill_thread( thread, 0 );  /* normal death */
 217         else
 218             fatal_protocol_perror( thread, "sendmsg" );
 219     }
 220 }
 221
 222 /* receive a file descriptor on the process socket */
 223 int receive_fd( struct process *process )
 224 {
 225     struct send_fd data;
 226     int fd, ret;
 227
 228 #ifdef HAVE_MSGHDR_ACCRIGHTS
 229     msghdr.msg_accrightslen = sizeof(int);
 230     msghdr.msg_accrights = (void *)&fd;
 231 #else  /* HAVE_MSGHDR_ACCRIGHTS */
 232     msghdr.msg_control    = &cmsg;
 233     msghdr.msg_controllen = sizeof(cmsg);
 234     cmsg.fd = -1;
 235 #endif  /* HAVE_MSGHDR_ACCRIGHTS */
 236
 237     myiovec.iov_base = &data;
 238     myiovec.iov_len  = sizeof(data);
 239
 240     ret = recvmsg( process->obj.fd, &msghdr, 0 );
 241 #ifndef HAVE_MSGHDR_ACCRIGHTS
 242     fd = cmsg.fd;
 243 #endif
 244
 245     if (ret == sizeof(data))
 246     {
 247         struct thread *thread = get_thread_from_id( data.tid );
 248         if (!thread || thread->process != process)
 249         {
 250             if (debug_level)
 251                 fprintf( stderr, "%08x: *fd* %d <- %d bad thread id\n",
 252                          (unsigned int)data.tid, data.fd, fd );
 253             close( fd );
 254         }
 255         else
 256         {
 257             if (debug_level)
 258                 fprintf( stderr, "%08x: *fd* %d <- %d\n",
 259                          (unsigned int)thread, data.fd, fd );
 260             thread_add_inflight_fd( thread, data.fd, fd );
 261         }
 262         return 0;
 263     }
 264
 265     if (!ret)
 266     {
 267         set_select_events( &process->obj, -1 );  /* stop waiting on it */
 268     }
 269     else if (ret > 0)
 270     {
 271         fprintf( stderr, "Protocol error: process %p: partial recvmsg %d for fd\n", process, ret );
 272         kill_process( process, NULL, 1 );
 273     }
 274     else if (ret < 0)
 275     {
 276         if (errno != EWOULDBLOCK && errno != EAGAIN)
 277         {
 278             fprintf( stderr, "Protocol error: process %p: ", process );
 279             perror( "recvmsg" );
 280             kill_process( process, NULL, 1 );
 281         }
 282     }
 283     return -1;
 284 }
 285
 286 /* send the wakeup signal to a thread */
 287 int send_thread_wakeup( struct thread *thread, int signaled )
 288 {
 289     int ret = write( thread->wait_fd, &signaled, sizeof(signaled) );
 290     if (ret == sizeof(signaled)) return 0;
 291     if (ret >= 0)
 292         fatal_protocol_error( thread, "partial wakeup write %d\n", ret );
 293     else if (errno == EPIPE)
 294         kill_thread( thread, 0 );  /* normal death */
 295     else
 296         fatal_protocol_perror( thread, "write" );
 297     return -1;
 298 }
 299
 300 /* send an fd to a client */
 301 int send_client_fd( struct thread *thread, int fd, handle_t handle )
 302 {
 303     int ret;
 304
 305     if (debug_level)
 306         fprintf( stderr, "%08x: *fd* %d -> %d\n", (unsigned int)thread, handle, fd );
 307
 308 #ifdef HAVE_MSGHDR_ACCRIGHTS
 309     msghdr.msg_accrightslen = sizeof(fd);
 310     msghdr.msg_accrights = (void *)&fd;
 311 #else  /* HAVE_MSGHDR_ACCRIGHTS */
 312     msghdr.msg_control    = &cmsg;
 313     msghdr.msg_controllen = sizeof(cmsg);
 314     cmsg.fd = fd;
 315 #endif  /* HAVE_MSGHDR_ACCRIGHTS */
 316
 317     myiovec.iov_base = (void *)&handle;
 318     myiovec.iov_len  = sizeof(handle);
 319
 320     ret = sendmsg( thread->obj.fd, &msghdr, 0 );
 321
 322     if (ret > 0) return 0;
 323     if (errno == EPIPE)
 324     {
 325         kill_thread( thread, 0 );  /* normal death */
 326     }
 327     else
 328     {
 329         fatal_protocol_perror( thread, "sendmsg" );
 330     }
 331     return -1;
 332 }
 333
 334 static void master_socket_dump( struct object *obj, int verbose )
 335 {
 336     struct master_socket *sock = (struct master_socket *)obj;
 337     assert( obj->ops == &master_socket_ops );
 338     fprintf( stderr, "Master socket fd=%d\n", sock->obj.fd );
 339 }
 340
 341 /* handle a socket event */
 342 static void master_socket_poll_event( struct object *obj, int event )
 343 {
 344     struct master_socket *sock = (struct master_socket *)obj;
 345     assert( obj->ops == &master_socket_ops );
 346
 347     assert( sock == master_socket );  /* there is only one master socket */
 348
 349     if (event & (POLLERR | POLLHUP))
 350     {
 351         /* this is not supposed to happen */
 352         fprintf( stderr, "wineserver: Error on master socket\n" );
 353         release_object( obj );
 354     }
 355     else if (event & POLLIN)
 356     {
 357         struct sockaddr_un dummy;
 358         int len = sizeof(dummy);
 359         int client = accept( master_socket->obj.fd, (struct sockaddr *) &dummy, &len );
 360         if (client != -1) create_process( client );
 361     }
 362 }
 363
 364 /* remove the socket upon exit */
 365 static void socket_cleanup(void)
 366 {
 367     static int do_it_once;
 368     if (!do_it_once++) unlink( SOCKETNAME );
 369 }
 370
 371 static void master_socket_destroy( struct object *obj )
 372 {
 373     socket_cleanup();
 374 }
 375
 376 static void request_socket_dump( struct object *obj, int verbose )
 377 {
 378     struct request_socket *sock = (struct request_socket *)obj;
 379     assert( obj->ops == &request_socket_ops );
 380     fprintf( stderr, "Request socket fd=%d thread=%p\n", sock->obj.fd, sock->thread );
 381 }
 382
 383 /* handle a request socket event */
 384 static void request_socket_poll_event( struct object *obj, int event )
 385 {
 386     struct request_socket *sock = (struct request_socket *)obj;
 387     assert( obj->ops == &request_socket_ops );
 388
 389     if (event & (POLLERR | POLLHUP)) kill_thread( sock->thread, 0 );
 390     else if (event & POLLIN)
 391     {
 392         struct thread *thread = sock->thread;
 393         union generic_request req;
 394         int ret;
 395
 396         if ((ret = read( sock->obj.fd, &req, sizeof(req) )) == sizeof(req))
 397         {
 398             call_req_handler( thread, &req );
 399             return;
 400         }
 401         if (!ret)  /* closed pipe */
 402             kill_thread( thread, 0 );
 403         else if (ret > 0)
 404             fatal_protocol_error( thread, "partial read %d\n", ret );
 405         else
 406             fatal_protocol_perror( thread, "read" );
 407     }
 408 }
 409
 410 /* create a request socket and send the fd to the client thread */
 411 struct object *create_request_socket( struct thread *thread )
 412 {
 413     struct request_socket *sock;
 414     int fd[2];
 415
 416     if (pipe( fd )) return NULL;
 417     if (!(sock = alloc_object( &request_socket_ops, fd[0] )))
 418     {
 419         close( fd[1] );
 420         return NULL;
 421     }
 422     sock->thread = thread;
 423     send_client_fd( thread, fd[1], 0 );
 424     close( fd[1] );
 425     fcntl( fd[0], F_SETFL, O_NONBLOCK );
 426     set_select_events( &sock->obj, POLLIN );
 427     return &sock->obj;
 428 }
 429
 430 /* return the configuration directory ($WINEPREFIX or $HOME/.wine) */
 431 const char *get_config_dir(void)
 432 {
 433     static char *confdir;
 434     if (!confdir)
 435     {
 436         const char *prefix = getenv( "WINEPREFIX" );
 437         if (prefix)
 438         {
 439             int len = strlen(prefix);
 440             if (!(confdir = strdup( prefix ))) fatal_error( "out of memory\n" );
 441             if (len > 1 && confdir[len-1] == '/') confdir[len-1] = 0;
 442         }
 443         else
 444         {
 445             const char *home = getenv( "HOME" );
 446             if (!home)
 447             {
 448                 struct passwd *pwd = getpwuid( getuid() );
 449                 if (!pwd) fatal_error( "could not find your home directory\n" );
 450                 home = pwd->pw_dir;
 451             }
 452             if (!(confdir = malloc( strlen(home) + strlen(CONFDIR) + 1 )))
 453                 fatal_error( "out of memory\n" );
 454             strcpy( confdir, home );
 455             strcat( confdir, CONFDIR );
 456         }
 457         mkdir( confdir, 0755 );  /* just in case */
 458     }
 459     return confdir;
 460 }
 461
 462 /* create the server directory and chdir to it */
 463 static void create_server_dir(void)
 464 {
 465     char hostname[64];
 466     char *serverdir;
 467     const char *confdir = get_config_dir();
 468     struct stat st;
 469
 470     if (gethostname( hostname, sizeof(hostname) ) == -1) fatal_perror( "gethostname" );
 471
 472     if (!(serverdir = malloc( strlen(confdir) + strlen(SERVERDIR) + strlen(hostname) + 1 )))
 473         fatal_error( "out of memory\n" );
 474
 475     strcpy( serverdir, confdir );
 476     strcat( serverdir, SERVERDIR );
 477     strcat( serverdir, hostname );
 478
 479     if (chdir( serverdir ) == -1)
 480     {
 481         if (errno != ENOENT) fatal_perror( "chdir %s", serverdir );
 482         if (mkdir( serverdir, 0700 ) == -1) fatal_perror( "mkdir %s", serverdir );
 483         if (chdir( serverdir ) == -1) fatal_perror( "chdir %s", serverdir );
 484     }
 485     if (stat( ".", &st ) == -1) fatal_perror( "stat %s", serverdir );
 486     if (!S_ISDIR(st.st_mode)) fatal_error( "%s is not a directory\n", serverdir );
 487     if (st.st_uid != getuid()) fatal_error( "%s is not owned by you\n", serverdir );
 488     if (st.st_mode & 077) fatal_error( "%s must not be accessible by other users\n", serverdir );
 489 }
 490
 491 /* open the master server socket and start waiting for new clients */
 492 void open_master_socket(void)
 493 {
 494     struct sockaddr_un addr;
 495     int fd, slen;
 496
 497     /* make sure no request is larger than the maximum size */
 498     assert( sizeof(union generic_request) == sizeof(struct request_max_size) );
 499
 500     create_server_dir();
 501     if ((fd = socket( AF_UNIX, SOCK_STREAM, 0 )) == -1) fatal_perror( "socket" );
 502     addr.sun_family = AF_UNIX;
 503     strcpy( addr.sun_path, SOCKETNAME );
 504     slen = sizeof(addr) - sizeof(addr.sun_path) + strlen(addr.sun_path) + 1;
 505 #ifdef HAVE_SOCKADDR_SUN_LEN
 506     addr.sun_len = slen;
 507 #endif
 508     if (bind( fd, (struct sockaddr *)&addr, slen ) == -1)
 509     {
 510         if ((errno == EEXIST) || (errno == EADDRINUSE))
 511             exit(0);  /* pretend we succeeded to start */
 512         else
 513             fatal_perror( "bind" );
 514     }
 515     atexit( socket_cleanup );
 516
 517     chmod( SOCKETNAME, 0600 );  /* make sure no other user can connect */
 518     if (listen( fd, 5 ) == -1) fatal_perror( "listen" );
 519
 520     if (!(master_socket = alloc_object( &master_socket_ops, fd )))
 521         fatal_error( "out of memory\n" );
 522     set_select_events( &master_socket->obj, POLLIN );
 523
 524     /* setup msghdr structure constant fields */
 525     msghdr.msg_name    = NULL;
 526     msghdr.msg_namelen = 0;
 527     msghdr.msg_iov     = &myiovec;
 528     msghdr.msg_iovlen  = 1;
 529
 530     /* go in the background */
 531     switch(fork())
 532     {
 533     case -1:
 534         fatal_perror( "fork" );
 535     case 0:
 536         setsid();
 537         break;
 538     default:
 539         _exit(0);  /* do not call atexit functions */
 540     }
 541 }
 542
 543 /* close the master socket and stop waiting for new clients */
 544 void close_master_socket(void)
 545 {
 546     /* if a new client is waiting, we keep on running */
 547     if (!check_select_events( master_socket->obj.fd, POLLIN ))
 548         release_object( master_socket );
 549 }
 550
 551 /* lock/unlock the master socket to stop accepting new clients */
 552 void lock_master_socket( int locked )
 553 {
 554     set_select_events( &master_socket->obj, locked ? 0 : POLLIN );
 555 }