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
  37 /* Some versions of glibc don't define this */
  38 #ifndef SCM_RIGHTS
  39 #define SCM_RIGHTS 1
  40 #endif
  41
  42  /* path names for server master Unix socket */
  43 #define CONFDIR    "/.wine"        /* directory for Wine config relative to $HOME */
  44 #define SERVERDIR  "/wineserver-"  /* server socket directory (hostname appended) */
  45 #define SOCKETNAME "socket"        /* name of the socket file */
  46
  47 struct master_socket
  48 {
  49     struct object       obj;         /* object header */
  50 };
  51
  52 static void master_socket_dump( struct object *obj, int verbose );
  53 static void master_socket_poll_event( struct object *obj, int event );
  54 static void master_socket_destroy( struct object *obj );
  55
  56 static const struct object_ops master_socket_ops =
  57 {
  58     sizeof(struct master_socket),  /* size */
  59     master_socket_dump,            /* dump */
  60     no_add_queue,                  /* add_queue */
  61     NULL,                          /* remove_queue */
  62     NULL,                          /* signaled */
  63     NULL,                          /* satisfied */
  64     NULL,                          /* get_poll_events */
  65     master_socket_poll_event,      /* poll_event */
  66     no_read_fd,                    /* get_read_fd */
  67     no_write_fd,                   /* get_write_fd */
  68     no_flush,                      /* flush */
  69     no_get_file_info,              /* get_file_info */
  70     master_socket_destroy          /* destroy */
  71 };
  72
  73
  74 struct thread *current = NULL;  /* thread handling the current request */
  75
  76 static struct master_socket *master_socket;  /* the master socket object */
  77
  78 /* socket communication static structures */
  79 static struct iovec myiovec;
  80 static struct msghdr msghdr = { NULL, 0, &myiovec, 1, };
  81 #ifndef HAVE_MSGHDR_ACCRIGHTS
  82 struct cmsg_fd
  83 {
  84     int len;   /* sizeof structure */
  85     int level; /* SOL_SOCKET */
  86     int type;  /* SCM_RIGHTS */
  87     int fd;    /* fd to pass */
  88 };
  89 static struct cmsg_fd cmsg = { sizeof(cmsg), SOL_SOCKET, SCM_RIGHTS, -1 };
  90 #endif  /* HAVE_MSGHDR_ACCRIGHTS */
  91
  92 /* complain about a protocol error and terminate the client connection */
  93 void fatal_protocol_error( struct thread *thread, const char *err, ... )
  94 {
  95     va_list args;
  96
  97     va_start( args, err );
  98     fprintf( stderr, "Protocol error:%p: ", thread );
  99     vfprintf( stderr, err, args );
 100     va_end( args );
 101     kill_thread( thread, PROTOCOL_ERROR );
 102 }
 103
 104 /* die on a fatal error */
 105 static void fatal_error( const char *err, ... )
 106 {
 107     va_list args;
 108
 109     va_start( args, err );
 110     fprintf( stderr, "wineserver: " );
 111     vfprintf( stderr, err, args );
 112     va_end( args );
 113     exit(1);
 114 }
 115
 116 /* die on a fatal error */
 117 static void fatal_perror( const char *err, ... )
 118 {
 119     va_list args;
 120
 121     va_start( args, err );
 122     fprintf( stderr, "wineserver: " );
 123     vfprintf( stderr, err, args );
 124     perror( " " );
 125     va_end( args );
 126     exit(1);
 127 }
 128
 129 /* call a request handler */
 130 static void call_req_handler( struct thread *thread, enum request req, int fd )
 131 {
 132     current = thread;
 133     clear_error();
 134
 135     if (debug_level) trace_request( req, fd );
 136
 137     if (req < REQ_NB_REQUESTS)
 138     {
 139         req_handlers[req].handler( current->buffer, fd );
 140         if (current && !current->wait) send_reply( current );
 141         current = NULL;
 142         return;
 143     }
 144     fatal_protocol_error( current, "bad request %d\n", req );
 145 }
 146
 147 /* set the fd to pass to the thread */
 148 void set_reply_fd( struct thread *thread, int pass_fd )
 149 {
 150     assert( thread->pass_fd == -1 );
 151     thread->pass_fd = pass_fd;
 152 }
 153
 154 /* send a reply to a thread */
 155 void send_reply( struct thread *thread )
 156 {
 157     assert( !thread->wait );
 158     if (debug_level) trace_reply( thread );
 159     if (!write_request( thread )) set_select_events( &thread->obj, POLLOUT );
 160 }
 161
 162 /* read a message from a client that has something to say */
 163 void read_request( struct thread *thread )
 164 {
 165     int ret;
 166     enum request req;
 167
 168 #ifdef HAVE_MSGHDR_ACCRIGHTS
 169     msghdr.msg_accrightslen = sizeof(int);
 170     msghdr.msg_accrights = (void *)&thread->pass_fd;
 171 #else  /* HAVE_MSGHDR_ACCRIGHTS */
 172     msghdr.msg_control    = &cmsg;
 173     msghdr.msg_controllen = sizeof(cmsg);
 174     cmsg.fd = -1;
 175 #endif  /* HAVE_MSGHDR_ACCRIGHTS */
 176
 177     assert( thread->pass_fd == -1 );
 178
 179     myiovec.iov_base = (void *)&req;
 180     myiovec.iov_len  = sizeof(req);
 181
 182     ret = recvmsg( thread->obj.fd, &msghdr, 0 );
 183 #ifndef HAVE_MSGHDR_ACCRIGHTS
 184     thread->pass_fd = cmsg.fd;
 185 #endif
 186
 187     if (ret == sizeof(req))
 188     {
 189         int pass_fd = thread->pass_fd;
 190         thread->pass_fd = -1;
 191         call_req_handler( thread, req, pass_fd );
 192         if (pass_fd != -1) close( pass_fd );
 193         return;
 194     }
 195     if (ret == -1)
 196     {
 197         perror("recvmsg");
 198         kill_thread( thread, BROKEN_PIPE );
 199         return;
 200     }
 201     if (!ret)  /* closed pipe */
 202     {
 203         kill_thread( thread, BROKEN_PIPE );
 204         return;
 205     }
 206     fatal_protocol_error( thread, "partial message received %d/%d\n", ret, sizeof(req) );
 207 }
 208
 209 /* send a message to a client that is ready to receive something */
 210 int write_request( struct thread *thread )
 211 {
 212     int ret;
 213
 214     if (thread->pass_fd == -1)
 215     {
 216         ret = write( thread->obj.fd, &thread->error, sizeof(thread->error) );
 217         if (ret == sizeof(thread->error)) goto ok;
 218     }
 219     else  /* we have an fd to send */
 220     {
 221 #ifdef HAVE_MSGHDR_ACCRIGHTS
 222         msghdr.msg_accrightslen = sizeof(int);
 223         msghdr.msg_accrights = (void *)&thread->pass_fd;
 224 #else  /* HAVE_MSGHDR_ACCRIGHTS */
 225         msghdr.msg_control    = &cmsg;
 226         msghdr.msg_controllen = sizeof(cmsg);
 227         cmsg.fd = thread->pass_fd;
 228 #endif  /* HAVE_MSGHDR_ACCRIGHTS */
 229
 230         myiovec.iov_base = (void *)&thread->error;
 231         myiovec.iov_len  = sizeof(thread->error);
 232
 233         ret = sendmsg( thread->obj.fd, &msghdr, 0 );
 234         close( thread->pass_fd );
 235         thread->pass_fd = -1;
 236         if (ret == sizeof(thread->error)) goto ok;
 237     }
 238     if (ret == -1)
 239     {
 240         if (errno == EWOULDBLOCK) return 0;  /* not a fatal error */
 241         if (errno != EPIPE) perror("sendmsg");
 242     }
 243     else fprintf( stderr, "Partial message sent %d/%d\n", ret, sizeof(thread->error) );
 244     kill_thread( thread, BROKEN_PIPE );
 245     return -1;
 246
 247  ok:
 248     set_select_events( &thread->obj, POLLIN );
 249     return 1;
 250 }
 251
 252 static void master_socket_dump( struct object *obj, int verbose )
 253 {
 254     struct master_socket *sock = (struct master_socket *)obj;
 255     assert( obj->ops == &master_socket_ops );
 256     fprintf( stderr, "Master socket fd=%d\n", sock->obj.fd );
 257 }
 258
 259 /* handle a socket event */
 260 static void master_socket_poll_event( struct object *obj, int event )
 261 {
 262     struct master_socket *sock = (struct master_socket *)obj;
 263     assert( obj->ops == &master_socket_ops );
 264
 265     assert( sock == master_socket );  /* there is only one master socket */
 266
 267     if (event & (POLLERR | POLLHUP))
 268     {
 269         /* this is not supposed to happen */
 270         fprintf( stderr, "wineserver: Error on master socket\n" );
 271         release_object( obj );
 272     }
 273     else if (event & POLLIN)
 274     {
 275         struct sockaddr_un dummy;
 276         int len = sizeof(dummy);
 277         int client = accept( master_socket->obj.fd, &dummy, &len );
 278         if (client != -1) create_process( client, NULL, NULL, "", 1 );
 279     }
 280 }
 281
 282 /* remove the socket upon exit */
 283 static void socket_cleanup(void)
 284 {
 285     unlink( SOCKETNAME );
 286 }
 287
 288 static void master_socket_destroy( struct object *obj )
 289 {
 290     socket_cleanup();
 291 }
 292
 293 /* return the configuration directory ($HOME/.wine) */
 294 static const char *get_config_dir(void)
 295 {
 296     static char *confdir;
 297     if (!confdir)
 298     {
 299         const char *home = getenv( "HOME" );
 300         if (!home)
 301         {
 302             struct passwd *pwd = getpwuid( getuid() );
 303             if (!pwd) fatal_error( "could not find your home directory\n" );
 304             home = pwd->pw_dir;
 305         }
 306         if (!(confdir = malloc( strlen(home) + strlen(CONFDIR) + 1 )))
 307             fatal_error( "out of memory\n" );
 308         strcpy( confdir, home );
 309         strcat( confdir, CONFDIR );
 310         mkdir( confdir, 0755 );  /* just in case */
 311     }
 312     return confdir;
 313 }
 314
 315 /* create the server directory and chdir to it */
 316 static void create_server_dir(void)
 317 {
 318     char hostname[64];
 319     char *serverdir;
 320     const char *confdir = get_config_dir();
 321     struct stat st;
 322
 323     if (gethostname( hostname, sizeof(hostname) ) == -1) fatal_perror( "gethostname" );
 324
 325     if (!(serverdir = malloc( strlen(confdir) + strlen(SERVERDIR) + strlen(hostname) + 1 )))
 326         fatal_error( "out of memory\n" );
 327
 328     strcpy( serverdir, confdir );
 329     strcat( serverdir, SERVERDIR );
 330     strcat( serverdir, hostname );
 331
 332     if (chdir( serverdir ) == -1)
 333     {
 334         if (errno != ENOENT) fatal_perror( "chdir %s", serverdir );
 335         if (mkdir( serverdir, 0700 ) == -1) fatal_perror( "mkdir %s", serverdir );
 336         if (chdir( serverdir ) == -1) fatal_perror( "chdir %s", serverdir );
 337     }
 338     if (stat( ".", &st ) == -1) fatal_perror( "stat %s", serverdir );
 339     if (!S_ISDIR(st.st_mode)) fatal_error( "%s is not a directory\n", serverdir );
 340     if (st.st_uid != getuid()) fatal_error( "%s is not owned by you\n", serverdir );
 341     if (st.st_mode & 077) fatal_error( "%s must not be accessible by other users\n", serverdir );
 342 }
 343
 344 /* open the master server socket and start waiting for new clients */
 345 void open_master_socket(void)
 346 {
 347     struct sockaddr_un addr;
 348     int fd;
 349
 350     create_server_dir();
 351     if ((fd = socket( AF_UNIX, SOCK_STREAM, 0 )) == -1) fatal_perror( "socket" );
 352     addr.sun_family = AF_UNIX;
 353     strcpy( addr.sun_path, "socket" );
 354     if (bind( fd, &addr, sizeof(addr.sun_family) + strlen(addr.sun_path) ) == -1)
 355     {
 356         if ((errno == EEXIST) || (errno == EADDRINUSE))
 357             fatal_error( "another server is already running\n" );
 358         else
 359             fatal_perror( "bind" );
 360     }
 361     atexit( socket_cleanup );
 362
 363     chmod( "socket", 0600 );  /* make sure no other user can connect */
 364     if (listen( fd, 5 ) == -1) fatal_perror( "listen" );
 365
 366     if (!(master_socket = alloc_object( &master_socket_ops, fd )))
 367         fatal_error( "out of memory\n" );
 368     set_select_events( &master_socket->obj, POLLIN );
 369 }
 370
 371 /* close the master socket and stop waiting for new clients */
 372 void close_master_socket(void)
 373 {
 374     release_object( master_socket );
 375 }
 376
 377 /* lock/unlock the master socket to stop accepting new clients */
 378 void lock_master_socket( int locked )
 379 {
 380     set_select_events( &master_socket->obj, locked ? 0 : POLLIN );
 381 }
 382
 383 /* debugger support operations */
 384 DECL_HANDLER(debugger)
 385 {
 386     switch ( req->op )
 387     {
 388     case DEBUGGER_FREEZE_ALL:
 389         suspend_all_threads();
 390         break;
 391
 392     case DEBUGGER_UNFREEZE_ALL:
 393         resume_all_threads();
 394         break;
 395     }
 396 }