/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1988, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#if 0
#ifndef lint
static const char copyright[] =
"@(#) Copyright (c) 1988, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
static char sccsid[] = "@(#)chroot.c 8.1 (Berkeley) 6/9/93";
#endif /* not lint */
#endif
#include <sys/cdefs.h>
#include <sys/types.h>
#include <sys/procctl.h>
#include <ctype.h>
#include <err.h>
#include <grp.h>
#include <limits.h>
#include <paths.h>
#include <pwd.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
static void usage(void) __dead2;
int
main(int argc, char *argv[])
{
struct group *gp;
struct passwd *pw;
char *endp, *p, *user, *group, *grouplist;
const char *shell;
gid_t gid, *gidlist;
uid_t uid;
int arg, ch, error, gids;
long ngroups_max;
bool nonprivileged;
gid = 0;
uid = 0;
user = group = grouplist = NULL;
nonprivileged = false;
while ((ch = getopt(argc, argv, "G:g:u:n")) != -1) {
switch(ch) {
case 'u':
user = optarg;
if (*user == '\0')
usage();
break;
case 'g':
group = optarg;
if (*group == '\0')
usage();
break;
case 'G':
grouplist = optarg;
if (*grouplist == '\0')
usage();
break;
case 'n':
nonprivileged = true;
break;
case '?':
default:
usage();
}
}
argc -= optind;
argv += optind;
if (argc < 1)
usage();
if (group != NULL) {
if (isdigit((unsigned char)*group)) {
gid = (gid_t)strtoul(group, &endp, 0);
if (*endp != '\0')
goto getgroup;
} else {
getgroup:
if ((gp = getgrnam(group)) != NULL)
gid = gp->gr_gid;
else
errx(1, "no such group `%s'", group);
}
}
ngroups_max = sysconf(_SC_NGROUPS_MAX) + 1;
if ((gidlist = malloc(sizeof(gid_t) * ngroups_max)) == NULL)
err(1, "malloc");
for (gids = 0;
(p = strsep(&grouplist, ",")) != NULL && gids < ngroups_max; ) {
if (*p == '\0')
continue;
if (isdigit((unsigned char)*p)) {
gidlist[gids] = (gid_t)strtoul(p, &endp, 0);
if (*endp != '\0')
goto getglist;
} else {
getglist:
if ((gp = getgrnam(p)) != NULL)
gidlist[gids] = gp->gr_gid;
else
errx(1, "no such group `%s'", p);
}
gids++;
}
if (p != NULL && gids == ngroups_max)
errx(1, "too many supplementary groups provided");
if (user != NULL) {
if (isdigit((unsigned char)*user)) {
uid = (uid_t)strtoul(user, &endp, 0);
if (*endp != '\0')
goto getuser;
} else {
getuser:
if ((pw = getpwnam(user)) != NULL)
uid = pw->pw_uid;
else
errx(1, "no such user `%s'", user);
}
}
if (nonprivileged) {
arg = PROC_NO_NEW_PRIVS_ENABLE;
error = procctl(P_PID, getpid(), PROC_NO_NEW_PRIVS_CTL, &arg);
if (error != 0)
err(1, "procctl");
}
if (chdir(argv[0]) == -1 || chroot(".") == -1)
err(1, "%s", argv[0]);
if (gids && setgroups(gids, gidlist) == -1)
err(1, "setgroups");
if (group && setgid(gid) == -1)
err(1, "setgid");
if (user && setuid(uid) == -1)
err(1, "setuid");
if (argv[1]) {
execvp(argv[1], &argv[1]);
err(1, "%s", argv[1]);
}
if (!(shell = getenv("SHELL")))
shell = _PATH_BSHELL;
execlp(shell, shell, "-i", (char *)NULL);
err(1, "%s", shell);
/* NOTREACHED */
}
static void
usage(void)
{
(void)fprintf(stderr, "usage: chroot [-g group] [-G group,group,...] "
"[-u user] [-n] newroot [command]\n");
exit(1);
}
plain