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
31#include "libbb.h"
32
33/* Ask the user for a password.
34 * Return 1 if the user gives the correct password for entry PW,
35 * 0 if not.  Return 1 without asking if PW has an empty password.
36 *
37 * NULL pw means "just fake it for login with bad username" */
38
39int correct_password(const struct passwd *pw)
40{
41	char *unencrypted, *encrypted;
42	const char *correct;
43
44	/* fake salt. crypt() can choke otherwise. */
45	correct = "aa";
46	if (!pw) {
47		/* "aa" will never match */
48		goto fake_it;
49	}
50	correct = pw->pw_passwd;
51#if ENABLE_FEATURE_SHADOWPASSWDS
52	if ((correct[0] == 'x' || correct[0] == '*') && !correct[1]) {
53		/* Using _r function to avoid pulling in static buffers */
54		struct spwd spw;
55		struct spwd *result;
56		char buffer[256];
57		correct = (getspnam_r(pw->pw_name, &spw, buffer, sizeof(buffer), &result)) ? "aa" : spw.sp_pwdp;
58	}
59#endif
60
61	if (!correct[0]) /* empty password field? */
62		return 1;
63
64 fake_it:
65	unencrypted = bb_askpass(0, "Password: ");
66	if (!unencrypted) {
67		return 0;
68	}
69	encrypted = crypt(unencrypted, correct);
70	memset(unencrypted, 0, strlen(unencrypted));
71	return strcmp(encrypted, correct) == 0;
72}
73