1 /* Copyright (C) 1993-2022 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/id.h>
20 
21 /* Set the uid set for the current user to UIDS (N of them).  */
22 int
seteuids(int n,const uid_t * uids)23 seteuids (int n, const uid_t *uids)
24 {
25   error_t err;
26   auth_t newauth;
27   int i;
28   gid_t new[n];
29 
30   /* Fault before taking locks.  */
31   for (i = 0; i < n; ++i)
32     new[i] = uids[i];
33 
34 retry:
35   HURD_CRITICAL_BEGIN;
36   __mutex_lock (&_hurd_id.lock);
37   err = _hurd_check_ids ();
38   if (! err)
39     {
40       /* Get a new auth port using those IDs.  */
41       err = __USEPORT (AUTH,
42 		       __auth_makeauth (port, NULL, 0, 0,
43 					new, n,
44 					_hurd_id.aux.uids, _hurd_id.aux.nuids,
45 					_hurd_id.gen.gids, _hurd_id.gen.ngids,
46 					_hurd_id.aux.gids, _hurd_id.aux.ngids,
47 					&newauth));
48     }
49   __mutex_unlock (&_hurd_id.lock);
50   HURD_CRITICAL_END;
51   if (err == EINTR)
52     /* Got a signal while inside an RPC of the critical section, retry again */
53     goto retry;
54 
55   if (err)
56     return __hurd_fail (err);
57 
58   /* Install the new auth port and reauthenticate everything.  */
59   err = __setauth (newauth);
60   __mach_port_deallocate (__mach_task_self (), newauth);
61   return err;
62 }
63