winsup/cygserver/msg.cc

   1 /* msg.cc: Single unix specification IPC interface for Cygwin.
   2
   3 This file is part of Cygwin.
   4
   5 This software is a copyrighted work licensed under the terms of the
   6 Cygwin license.  Please consult the file "CYGWIN_LICENSE" for
   7 details. */
   8
   9 #ifdef __OUTSIDE_CYGWIN__
  10 #include "woutsup.h"
  11
  12 #include <errno.h>
  13 #include <pthread.h>
  14 #include <stdio.h>
  15 #include <stdlib.h>
  16 #include <string.h>
  17 #include <time.h>
  18
  19 #include "cygserver.h"
  20 #include "process.h"
  21 #include "transport.h"
  22
  23 #include "cygserver_ipc.h"
  24 #include "cygserver_msg.h"
  25
  26 client_request_msg::client_request_msg ()
  27   : client_request (CYGSERVER_REQUEST_MSG,
  28                     &_parameters, sizeof (_parameters))
  29 {
  30 }
  31
  32 void
  33 client_request_msg::serve (transport_layer_base *const conn,
  34                            process_cache *const cache)
  35 {
  36   if (msglen () != sizeof (_parameters.in))
  37     {
  38       syscall_printf ("bad request body length: expecting %lu bytes, got %lu",
  39                       sizeof (_parameters), msglen ());
  40       error_code (EINVAL);
  41       msglen (0);
  42       return;
  43     }
  44   if (support_msgqueues == TUN_FALSE)
  45     {
  46       syscall_printf ("Message queue support not started");
  47       error_code (ENOSYS);
  48       if (_parameters.in.msgop == MSGOP_msgrcv)
  49         _parameters.out.rcv = -1;
  50       else
  51         _parameters.out.ret = -1;
  52       msglen (sizeof (_parameters.out));
  53       return;
  54     }
  55   process *const client = cache->process (_parameters.in.ipcblk.cygpid,
  56                                           _parameters.in.ipcblk.winpid);
  57   if (!client)
  58     {
  59       error_code (EAGAIN);
  60       msglen (0);
  61       return;
  62     }
  63   if (!conn->impersonate_client ())
  64     {
  65       client->release ();
  66       error_code (EACCES);
  67       msglen (0);
  68       return;
  69     }
  70   if (!adjust_identity_info (&_parameters.in.ipcblk))
  71     {
  72       client->release ();
  73       conn->revert_to_self ();
  74       error_code (EACCES);
  75       msglen (0);
  76       return;
  77     }
  78   /* Early revert_to_self since IPC code runs in kernel mode. */
  79   conn->revert_to_self ();
  80   /* sysv_msg.cc takes care of itself. */
  81   client->release ();
  82   thread td (client, &_parameters.in.ipcblk, true);
  83   int res;
  84   msgop_t msgop = _parameters.in.msgop; /* Get's overwritten otherwise. */
  85   switch (msgop)
  86     {
  87       case MSGOP_msgctl:
  88         res = msgctl (&td, &_parameters.in.ctlargs);
  89         break;
  90       case MSGOP_msgget:
  91         res = msgget (&td, &_parameters.in.getargs);
  92         break;
  93       case MSGOP_msgrcv:
  94         res = msgrcv (&td, &_parameters.in.rcvargs);
  95         break;
  96       case MSGOP_msgsnd:
  97         res = msgsnd (&td, &_parameters.in.sndargs);
  98         break;
  99       default:
 100         res = ENOSYS;
 101         td.td_retval[0] = -1;
 102         break;
 103     }
 104   /* Allocated by the call to adjust_identity_info(). */
 105   if (_parameters.in.ipcblk.gidlist)
 106     free (_parameters.in.ipcblk.gidlist);
 107   error_code (res);
 108   if (msgop == MSGOP_msgrcv)
 109     _parameters.out.rcv = td.td_retval[0];
 110   else
 111     _parameters.out.ret = td.td_retval[0];
 112   msglen (sizeof (_parameters.out));
 113 }
 114 #endif /* __OUTSIDE_CYGWIN__ */