1 // SPDX-License-Identifier: CDDL-1.0
2 /*
3 * CDDL HEADER START
4 *
5 * The contents of this file are subject to the terms of the
6 * Common Development and Distribution License (the "License").
7 * You may not use this file except in compliance with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or https://opensource.org/licenses/CDDL-1.0.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22 /*
23 * Copyright 2006 Ricardo Correia. All rights reserved.
24 * Use is subject to license terms.
25 */
26
27 #include <unistd.h>
28 #include <stdio.h>
29 #include <errno.h>
30 #include <stdlib.h>
31 #include <limits.h>
32 #include <string.h>
33
34 #include <zone.h>
35
36 zoneid_t
getzoneid(void)37 getzoneid(void)
38 {
39 char path[PATH_MAX];
40 char buf[128] = { '\0' };
41 char *cp;
42
43 int c = snprintf(path, sizeof (path), "/proc/self/ns/user");
44 /* This API doesn't have any error checking... */
45 if (c < 0 || c >= sizeof (path))
46 return (GLOBAL_ZONEID);
47
48 ssize_t r = readlink(path, buf, sizeof (buf) - 1);
49 if (r < 0)
50 return (GLOBAL_ZONEID);
51
52 cp = strchr(buf, '[');
53 if (cp == NULL)
54 return (GLOBAL_ZONEID);
55 cp++;
56
57 unsigned long n = strtoul(cp, NULL, 10);
58 if (n == ULONG_MAX && errno == ERANGE)
59 return (GLOBAL_ZONEID);
60 zoneid_t z = (zoneid_t)n;
61
62 return (z);
63 }
64