1/* vi: set sw=4 ts=4: */ 2/* 3 * Copyright 1989 - 1991, Julianne Frances Haugh <jockgrrl@austin.rr.com> 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. Neither the name of Julianne F. Haugh nor the names of its contributors 15 * may be used to endorse or promote products derived from this software 16 * without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY JULIE HAUGH AND CONTRIBUTORS ''AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL JULIE HAUGH OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 */ 30#include "libbb.h" 31 32/* Become the user and group(s) specified by PW. */ 33void FAST_FUNC change_identity(const struct passwd *pw) 34{ 35 int res; 36 37 res = initgroups(pw->pw_name, pw->pw_gid); 38 endgrent(); /* helps to close a fd used internally by libc */ 39 40 if (res != 0) { 41 /* 42 * If initgroups() fails because a system call is unimplemented 43 * then we are running on a Linux kernel compiled without multiuser 44 * support (CONFIG_MULTIUSER is not defined). 45 * 46 * If we are running without multiuser support *and* the target uid 47 * already matches the current uid then we can skip the change of 48 * identity. 49 */ 50 if (errno == ENOSYS && pw->pw_uid == getuid()) { 51 return; 52 } 53 54 bb_perror_msg_and_die("can't set groups"); 55 } 56 57 xsetgid(pw->pw_gid); 58 xsetuid(pw->pw_uid); 59} 60