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 <errno.h>
19 #include <unistd.h>
20 #include <hurd.h>
21 #include <sys/types.h>
22 #include <hurd/id.h>
23 #include <string.h>
24
25 /* Set the effective user ID of the calling process to UID. */
26 int
seteuid(uid_t uid)27 seteuid (uid_t uid)
28 {
29 auth_t newauth;
30 error_t err;
31
32 retry:
33 HURD_CRITICAL_BEGIN;
34 __mutex_lock (&_hurd_id.lock);
35 err = _hurd_check_ids ();
36
37 if (!err)
38 {
39 /* Make a new auth handle which has EUID as the first element in the
40 list of effective uids. */
41
42 if (_hurd_id.gen.nuids > 0)
43 {
44 _hurd_id.gen.uids[0] = uid;
45 _hurd_id.valid = 0;
46 }
47
48 err = __USEPORT (AUTH, __auth_makeauth
49 (port, NULL, MACH_MSG_TYPE_COPY_SEND, 0,
50 _hurd_id.gen.nuids ? _hurd_id.gen.uids : &uid,
51 _hurd_id.gen.nuids ?: 1,
52 _hurd_id.aux.uids, _hurd_id.aux.nuids,
53 _hurd_id.gen.gids, _hurd_id.gen.ngids,
54 _hurd_id.aux.gids, _hurd_id.aux.ngids,
55 &newauth));
56 }
57 __mutex_unlock (&_hurd_id.lock);
58 HURD_CRITICAL_END;
59 if (err == EINTR)
60 /* Got a signal while inside an RPC of the critical section, retry again */
61 goto retry;
62
63 if (err)
64 return __hurd_fail (err);
65
66 /* Install the new handle and reauthenticate everything. */
67 err = __setauth (newauth);
68 __mach_port_deallocate (__mach_task_self (), newauth);
69 return err;
70 }
71 libc_hidden_def (seteuid)
72