mirror of https://github.com/sudo-project/sudo.git
88 lines
2.6 KiB
C
88 lines
2.6 KiB
C
/*
|
|
* SPDX-License-Identifier: ISC
|
|
*
|
|
* Copyright (c) 2023 Todd C. Miller <Todd.Miller@sudo.ws>
|
|
*
|
|
* Permission to use, copy, modify, and distribute this software for any
|
|
* purpose with or without fee is hereby granted, provided that the above
|
|
* copyright notice and this permission notice appear in all copies.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
|
|
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
|
|
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
|
|
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
|
|
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
|
|
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
|
|
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
|
|
*/
|
|
|
|
/*
|
|
* This is an open source non-commercial project. Dear PVS-Studio, please check it.
|
|
* PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
|
|
*/
|
|
|
|
#include <config.h>
|
|
|
|
#include <stdio.h>
|
|
#include <fcntl.h>
|
|
#include <unistd.h>
|
|
|
|
#include <sudoers.h>
|
|
|
|
/*
|
|
* Pivot to a new root directory, storing the old root and old cwd
|
|
* in state. Changes current working directory to the new root.
|
|
* Returns true on success, else false.
|
|
*/
|
|
bool
|
|
pivot_root(const char *new_root, struct sudoers_pivot *state)
|
|
{
|
|
debug_decl(pivot_root, SUDOERS_DEBUG_UTIL);
|
|
|
|
state->saved_root = open("/", O_RDONLY);
|
|
state->saved_cwd = open(".", O_RDONLY);
|
|
if (state->saved_root == -1 || state->saved_cwd == -1 || chroot(new_root) == -1) {
|
|
if (state->saved_root != -1) {
|
|
close(state->saved_root);
|
|
state->saved_root = -1;
|
|
}
|
|
if (state->saved_cwd != -1) {
|
|
close(state->saved_cwd);
|
|
state->saved_cwd = -1;
|
|
}
|
|
debug_return_bool(false);
|
|
}
|
|
debug_return_bool(chdir("/") == 0);
|
|
}
|
|
|
|
/*
|
|
* Pivot back to the stored root directory and restore the old cwd.
|
|
* Returns true on success, else false.
|
|
*/
|
|
bool
|
|
unpivot_root(struct sudoers_pivot *state)
|
|
{
|
|
bool ret = true;
|
|
debug_decl(unpivot_root, SUDOERS_DEBUG_UTIL);
|
|
|
|
/* Order is important: restore old root, *then* change cwd. */
|
|
if (state->saved_root != -1) {
|
|
if (fchdir(state->saved_root) == -1 || chroot(".") == -1) {
|
|
sudo_warn("%s", U_("unable to restore root directory"));
|
|
ret = false;
|
|
}
|
|
close(state->saved_root);
|
|
state->saved_root = -1;
|
|
}
|
|
if (state->saved_cwd != -1) {
|
|
if (fchdir(state->saved_cwd) == -1) {
|
|
sudo_warn("%s", U_("unable to restore current working directory"));
|
|
ret = false;
|
|
}
|
|
close(state->saved_cwd);
|
|
state->saved_cwd = -1;
|
|
}
|
|
|
|
debug_return_bool(ret);
|
|
}
|