hurd/setauth.c

   1 /* Copyright (C) 1991-2017 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #include <hurd.h>
  19 #include <hurd/port.h>
  20 #include <hurd/id.h>
  21 #include "set-hooks.h"
  22
  23 /* Things in the library which want to be run when the auth port changes.  */
  24 DEFINE_HOOK (_hurd_reauth_hook, (auth_t new_auth));
  25
  26 #include <cthreads.h>
  27 static struct mutex reauth_lock = MUTEX_INITIALIZER;
  28
  29
  30 /* Set the auth port to NEW, and reauthenticate
  31    everything used by the library.  */
  32 error_t
  33 _hurd_setauth (auth_t new)
  34 {
  35   error_t err;
  36   unsigned int d;
  37   mach_port_t newport, ref;
  38
  39   /* Give the new send right a user reference.
  40      This is a good way to check that it is valid.  */
  41   if (err = __mach_port_mod_refs (__mach_task_self (), new,
  42                                   MACH_PORT_RIGHT_SEND, 1))
  43     return err;
  44
  45   HURD_CRITICAL_BEGIN;
  46
  47   /* We lock against another thread doing setauth.  Anyone who sets
  48      _hurd_ports[INIT_PORT_AUTH] some other way is asking to lose.  */
  49   __mutex_lock (&reauth_lock);
  50
  51   /* Install the new port in the cell.  */
  52   __mutex_lock (&_hurd_id.lock);
  53   _hurd_port_set (&_hurd_ports[INIT_PORT_AUTH], new);
  54   _hurd_id.valid = 0;
  55   if (_hurd_id.rid_auth)
  56     {
  57       __mach_port_deallocate (__mach_task_self (), _hurd_id.rid_auth);
  58       _hurd_id.rid_auth = MACH_PORT_NULL;
  59     }
  60   __mutex_unlock (&_hurd_id.lock);
  61
  62   if (_hurd_init_dtable != NULL)
  63     /* We just have the simple table we got at startup.
  64        Otherwise, a reauth_hook in dtable.c takes care of this.  */
  65     for (d = 0; d < _hurd_init_dtablesize; ++d)
  66       if (_hurd_init_dtable[d] != MACH_PORT_NULL)
  67         {
  68           mach_port_t new;
  69           ref = __mach_reply_port ();
  70           if (! __io_reauthenticate (_hurd_init_dtable[d],
  71                                      ref, MACH_MSG_TYPE_MAKE_SEND) &&
  72               ! HURD_PORT_USE (&_hurd_ports[INIT_PORT_AUTH],
  73                                __auth_user_authenticate
  74                                (port,
  75                                 ref, MACH_MSG_TYPE_MAKE_SEND,
  76                                 &new)))
  77             {
  78               __mach_port_deallocate (__mach_task_self (),
  79                                       _hurd_init_dtable[d]);
  80               _hurd_init_dtable[d] = new;
  81             }
  82           __mach_port_destroy (__mach_task_self (), ref);
  83         }
  84
  85   ref = __mach_reply_port ();
  86   if (__USEPORT (CRDIR,
  87                  ! __io_reauthenticate (port,
  88                                         ref, MACH_MSG_TYPE_MAKE_SEND) &&
  89                  ! __auth_user_authenticate (new,
  90                                              ref, MACH_MSG_TYPE_MAKE_SEND,
  91                                              &newport)))
  92     _hurd_port_set (&_hurd_ports[INIT_PORT_CRDIR], newport);
  93   __mach_port_destroy (__mach_task_self (), ref);
  94
  95   ref = __mach_reply_port ();
  96   if (__USEPORT (CWDIR,
  97                  ! __io_reauthenticate (port,
  98                                         ref, MACH_MSG_TYPE_MAKE_SEND) &&
  99                  ! __auth_user_authenticate (new,
 100                                              ref, MACH_MSG_TYPE_MAKE_SEND,
 101                                              &newport)))
 102     _hurd_port_set (&_hurd_ports[INIT_PORT_CWDIR], newport);
 103   __mach_port_destroy (__mach_task_self (), ref);
 104
 105   /* Run things which want to do reauthorization stuff.  */
 106   RUN_HOOK (_hurd_reauth_hook, (new));
 107
 108   __mutex_unlock (&reauth_lock);
 109
 110   HURD_CRITICAL_END;
 111
 112   return 0;
 113 }
 114
 115 int
 116 __setauth (auth_t new)
 117 {
 118   error_t err = _hurd_setauth (new);
 119   return err ? __hurd_fail (err) : 0;
 120 }
 121
 122 weak_alias (__setauth, setauth)