freebsd-skq/usr.sbin/jexec/jexec.c
jamie 7c0019fd30 Add libjail, a (somewhat) simpler interface to the jail_set and jail_get
system calls and the security.jail.param sysctls.

Approved by:	bz (mentor)
2009-06-24 18:18:35 +00:00

141 lines
3.7 KiB
C

/*-
* Copyright (c) 2003 Mike Barcroft <mike@FreeBSD.org>
* Copyright (c) 2008 Bjoern A. Zeeb <bz@FreeBSD.org>
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*
* $FreeBSD$
*/
#include <sys/param.h>
#include <sys/jail.h>
#include <sys/socket.h>
#include <sys/sysctl.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <err.h>
#include <errno.h>
#include <jail.h>
#include <limits.h>
#include <login_cap.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <pwd.h>
#include <unistd.h>
static void usage(void);
#define GET_USER_INFO do { \
pwd = getpwnam(username); \
if (pwd == NULL) { \
if (errno) \
err(1, "getpwnam: %s", username); \
else \
errx(1, "%s: no such user", username); \
} \
lcap = login_getpwclass(pwd); \
if (lcap == NULL) \
err(1, "getpwclass: %s", username); \
ngroups = ngroups_max; \
if (getgrouplist(username, pwd->pw_gid, groups, &ngroups) != 0) \
err(1, "getgrouplist: %s", username); \
} while (0)
int
main(int argc, char *argv[])
{
int jid;
login_cap_t *lcap = NULL;
struct passwd *pwd = NULL;
gid_t *groups = NULL;
int ch, ngroups, uflag, Uflag;
long ngroups_max;
char *username;
ch = uflag = Uflag = 0;
username = NULL;
ngroups_max = sysconf(_SC_NGROUPS_MAX) + 1;
if ((groups = malloc(sizeof(gid_t) * ngroups_max)) == NULL)
err(1, "malloc");
while ((ch = getopt(argc, argv, "nu:U:")) != -1) {
switch (ch) {
case 'n':
/* Specified name, now unused */
break;
case 'u':
username = optarg;
uflag = 1;
break;
case 'U':
username = optarg;
Uflag = 1;
break;
default:
usage();
}
}
argc -= optind;
argv += optind;
if (argc < 2)
usage();
if (uflag && Uflag)
usage();
if (uflag)
GET_USER_INFO;
jid = jail_getid(argv[0]);
if (jid < 0)
errx(1, "%s", jail_errmsg);
if (jail_attach(jid) == -1)
err(1, "jail_attach(%d)", jid);
if (chdir("/") == -1)
err(1, "chdir(): /");
if (username != NULL) {
if (Uflag)
GET_USER_INFO;
if (setgroups(ngroups, groups) != 0)
err(1, "setgroups");
if (setgid(pwd->pw_gid) != 0)
err(1, "setgid");
if (setusercontext(lcap, pwd, pwd->pw_uid,
LOGIN_SETALL & ~LOGIN_SETGROUP & ~LOGIN_SETLOGIN) != 0)
err(1, "setusercontext");
login_close(lcap);
}
if (execvp(argv[1], argv + 1) == -1)
err(1, "execvp(): %s", argv[1]);
exit(0);
}
static void
usage(void)
{
fprintf(stderr, "%s\n",
"usage: jexec [-u username | -U username] jail command ...");
exit(1);
}