1 /* Copyright (C) 1991-2022 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    <https://www.gnu.org/licenses/>.  */
17 
18 #include <hurd.h>
19 #include <hurd/port.h>
20 #include <hurd/id.h>
21 #include <hurdlock.h>
22 #include "set-hooks.h"
23 
24 /* Things in the library which want to be run when the auth port changes.  */
25 DEFINE_HOOK (_hurd_reauth_hook, (auth_t new_auth));
26 
27 static unsigned int reauth_lock = LLL_LOCK_INITIALIZER;
28 
29 /* Set the auth port to NEW, and reauthenticate
30    everything used by the library.  */
31 error_t
_hurd_setauth(auth_t new)32 _hurd_setauth (auth_t new)
33 {
34   error_t err;
35   unsigned int d;
36   mach_port_t newport, ref;
37 
38   /* Give the new send right a user reference.
39      This is a good way to check that it is valid.  */
40   if (err = __mach_port_mod_refs (__mach_task_self (), new,
41 				  MACH_PORT_RIGHT_SEND, 1))
42     return err;
43 
44   HURD_CRITICAL_BEGIN;
45 
46   /* We lock against another thread doing setauth.  Anyone who sets
47      _hurd_ports[INIT_PORT_AUTH] some other way is asking to lose.  */
48   __mutex_lock (&reauth_lock);
49 
50   /* Install the new port in the cell.  */
51   __mutex_lock (&_hurd_id.lock);
52   _hurd_port_set (&_hurd_ports[INIT_PORT_AUTH], new);
53   _hurd_id.valid = 0;
54   if (_hurd_id.rid_auth)
55     {
56       __mach_port_deallocate (__mach_task_self (), _hurd_id.rid_auth);
57       _hurd_id.rid_auth = MACH_PORT_NULL;
58     }
59   __mutex_unlock (&_hurd_id.lock);
60 
61   if (_hurd_init_dtable != NULL)
62     /* We just have the simple table we got at startup.
63        Otherwise, a reauth_hook in dtable.c takes care of this.  */
64     for (d = 0; d < _hurd_init_dtablesize; ++d)
65       if (_hurd_init_dtable[d] != MACH_PORT_NULL)
66 	{
67 	  mach_port_t new;
68 	  ref = __mach_reply_port ();
69 	  if (! __io_reauthenticate (_hurd_init_dtable[d],
70 				     ref, MACH_MSG_TYPE_MAKE_SEND)
71 	      && ! HURD_PORT_USE (&_hurd_ports[INIT_PORT_AUTH],
72 				  __auth_user_authenticate
73 				  (port,
74 				   ref, MACH_MSG_TYPE_MAKE_SEND,
75 				   &new)))
76 	    {
77 	      __mach_port_deallocate (__mach_task_self (),
78 				      _hurd_init_dtable[d]);
79 	      _hurd_init_dtable[d] = new;
80 	    }
81 	  __mach_port_destroy (__mach_task_self (), ref);
82 	}
83 
84   ref = __mach_reply_port ();
85   if (__USEPORT (CRDIR,
86 		 ! __io_reauthenticate (port,
87 					ref, MACH_MSG_TYPE_MAKE_SEND)
88 		 && ! __auth_user_authenticate (new,
89 						ref, MACH_MSG_TYPE_MAKE_SEND,
90 						&newport)))
91     _hurd_port_set (&_hurd_ports[INIT_PORT_CRDIR], newport);
92   __mach_port_destroy (__mach_task_self (), ref);
93 
94   ref = __mach_reply_port ();
95   if (__USEPORT (CWDIR,
96 		 ! __io_reauthenticate (port,
97 					ref, MACH_MSG_TYPE_MAKE_SEND)
98 		 && ! __auth_user_authenticate (new,
99 						ref, MACH_MSG_TYPE_MAKE_SEND,
100 						&newport)))
101     _hurd_port_set (&_hurd_ports[INIT_PORT_CWDIR], newport);
102   __mach_port_destroy (__mach_task_self (), ref);
103 
104   /* Run things which want to do reauthorization stuff.  */
105   RUN_HOOK (_hurd_reauth_hook, (new));
106 
107   __mutex_unlock (&reauth_lock);
108 
109   HURD_CRITICAL_END;
110 
111   return 0;
112 }
113 
114 int
__setauth(auth_t new)115 __setauth (auth_t new)
116 {
117   error_t err = _hurd_setauth (new);
118   return err ? __hurd_fail (err) : 0;
119 }
120 
121 weak_alias (__setauth, setauth)
122