sandbox-rlimit.c revision 262566 
1/* $OpenBSD: sandbox-rlimit.c,v 1.3 2011/06/23 09:34:13 djm Exp $ */
2/*
3 * Copyright (c) 2011 Damien Miller <djm@mindrot.org>
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17
18#include "includes.h"
19
20#ifdef SANDBOX_RLIMIT
21
22#include <sys/types.h>
23#include <sys/param.h>
24#include <sys/time.h>
25#include <sys/resource.h>
26
27#include <errno.h>
28#include <stdarg.h>
29#include <stdio.h>
30#include <stdlib.h>
31#include <string.h>
32#include <unistd.h>
33
34#include "log.h"
35#include "ssh-sandbox.h"
36#include "xmalloc.h"
37
38/* Minimal sandbox that sets zero nfiles, nprocs and filesize rlimits */
39
40struct ssh_sandbox {
41	pid_t child_pid;
42};
43
44struct ssh_sandbox *
45ssh_sandbox_init(struct monitor *monitor)
46{
47	struct ssh_sandbox *box;
48
49	/*
50	 * Strictly, we don't need to maintain any state here but we need
51	 * to return non-NULL to satisfy the API.
52	 */
53	debug3("%s: preparing rlimit sandbox", __func__);
54	box = xcalloc(1, sizeof(*box));
55	box->child_pid = 0;
56
57	return box;
58}
59
60void
61ssh_sandbox_child(struct ssh_sandbox *box)
62{
63	struct rlimit rl_zero;
64
65	rl_zero.rlim_cur = rl_zero.rlim_max = 0;
66
67#ifndef SANDBOX_SKIP_RLIMIT_FSIZE
68	if (setrlimit(RLIMIT_FSIZE, &rl_zero) == -1)
69		fatal("%s: setrlimit(RLIMIT_FSIZE, { 0, 0 }): %s",
70			__func__, strerror(errno));
71#endif
72#ifndef SANDBOX_SKIP_RLIMIT_NOFILE
73	if (setrlimit(RLIMIT_NOFILE, &rl_zero) == -1)
74		fatal("%s: setrlimit(RLIMIT_NOFILE, { 0, 0 }): %s",
75			__func__, strerror(errno));
76#endif
77#ifdef HAVE_RLIMIT_NPROC
78	if (setrlimit(RLIMIT_NPROC, &rl_zero) == -1)
79		fatal("%s: setrlimit(RLIMIT_NPROC, { 0, 0 }): %s",
80			__func__, strerror(errno));
81#endif
82}
83
84void
85ssh_sandbox_parent_finish(struct ssh_sandbox *box)
86{
87	free(box);
88	debug3("%s: finished", __func__);
89}
90
91void
92ssh_sandbox_parent_preauth(struct ssh_sandbox *box, pid_t child_pid)
93{
94	box->child_pid = child_pid;
95}
96
97#endif /* SANDBOX_RLIMIT */
98