New version from Tito.
This commit is contained in:
Rob Landley
parent
819b56b64a
commit
a13cca9cf4
374
libbb/obscure.c
374
libbb/obscure.c
@ -1,259 +1,179 @@
|
|||||||
/* vi: set sw=4 ts=4: */
|
/* vi: set sw=4 ts=4: */
|
||||||
/*
|
/*
|
||||||
* Copyright 1989 - 1994, Julianne Frances Haugh <jockgrrl@austin.rr.com>
|
* Mini weak password checker implementation for busybox
|
||||||
* Copyright 2006, Bernhard Fischer <busybox@busybox.net>
|
|
||||||
* All rights reserved.
|
|
||||||
*
|
*
|
||||||
* Redistribution and use in source and binary forms, with or without
|
* Copyright (C) 2006 Tito Ragusa <farmatito@tiscali.it>
|
||||||
* 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 Julianne F. Haugh 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 JULIE HAUGH AND CONTRIBUTORS ``AS IS'' AND
|
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
|
||||||
* 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 JULIE HAUGH 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.
|
|
||||||
*/
|
*/
|
||||||
|
|
||||||
/*
|
/* A good password:
|
||||||
* This version of obscure.c contains modifications to support "cracklib"
|
1) should contain at least six characters (man passwd);
|
||||||
* by Alec Muffet (alec.muffett@uk.sun.com). You must obtain the Cracklib
|
2) empty passwords are not permitted;
|
||||||
* library source code for this function to operate.
|
3) should contain a mix of four different types of characters
|
||||||
*/
|
upper case letters,
|
||||||
|
lower case letters,
|
||||||
|
numbers,
|
||||||
|
special characters such as !@#$%^&*,;".
|
||||||
|
This password types should not be permitted:
|
||||||
|
a) pure numbers: birthdates, social security number, license plate, phone numbers;
|
||||||
|
b) words and all letters only passwords (uppercase, lowercase or mixed)
|
||||||
|
as palindromes, consecutive or repetitive letters
|
||||||
|
or adjacent letters on your keyboard;
|
||||||
|
c) username, real name, company name or (e-mail?) address
|
||||||
|
in any form (as-is, reversed, capitalized, doubled, etc.).
|
||||||
|
(we can check only against username, gecos and hostname)
|
||||||
|
d) common and obvious letter-number replacements
|
||||||
|
(e.g. replace the letter O with number 0)
|
||||||
|
such as "M1cr0$0ft" or "P@ssw0rd" (CAVEAT: we cannot check for them
|
||||||
|
without the use of a dictionary).
|
||||||
|
|
||||||
|
For each missing type of characters an increase of password length is
|
||||||
|
requested.
|
||||||
|
|
||||||
|
If user is root we warn only.
|
||||||
|
|
||||||
|
CAVEAT: some older versions of crypt() truncates passwords to 8 chars,
|
||||||
|
so that aaaaaaaa1Q$ is equal to aaaaaaaa making it possible to fool
|
||||||
|
some of our checks. We don't test for this special case as newer versions
|
||||||
|
of crypt do not truncate passwords.
|
||||||
|
*/
|
||||||
|
|
||||||
#include <stdlib.h>
|
|
||||||
#include <stdio.h>
|
|
||||||
#include <string.h>
|
|
||||||
#include <ctype.h>
|
#include <ctype.h>
|
||||||
|
#include <unistd.h>
|
||||||
|
#include <string.h>
|
||||||
|
|
||||||
#include "libbb.h"
|
#include "libbb.h"
|
||||||
|
|
||||||
/*
|
|
||||||
* can't be a palindrome - like `R A D A R' or `M A D A M'
|
|
||||||
*/
|
|
||||||
|
|
||||||
static int palindrome(const char *newval)
|
/* passwords should consist of 6 (to 8 characters) */
|
||||||
|
#define MINLEN 6
|
||||||
|
|
||||||
|
|
||||||
|
static int string_checker_helper(const char *p1, const char *p2) __attribute__ ((__pure__));
|
||||||
|
|
||||||
|
static int string_checker_helper(const char *p1, const char *p2)
|
||||||
{
|
{
|
||||||
int i, j;
|
/* as-is or capitalized */
|
||||||
|
if (strcasecmp(p1, p2) == 0
|
||||||
i = strlen(newval);
|
/* as sub-string */
|
||||||
|
|| strcasestr(p2, p1) != NULL
|
||||||
for (j = 0; j < i; j++)
|
/* invert in case haystack is shorter than needle */
|
||||||
if (newval[i - j - 1] != newval[j])
|
|| strcasestr(p1, p2) != NULL)
|
||||||
return 0;
|
return 1;
|
||||||
|
return 0;
|
||||||
return 1;
|
|
||||||
}
|
}
|
||||||
|
|
||||||
/*
|
static int string_checker(const char *p1, const char *p2)
|
||||||
* more than half of the characters are different ones.
|
|
||||||
*/
|
|
||||||
|
|
||||||
static int similiar(const char *old, const char *newval)
|
|
||||||
{
|
{
|
||||||
int i, j;
|
|
||||||
|
|
||||||
for (i = j = 0; newval[i] && old[i]; i++)
|
|
||||||
if (strchr(newval, old[i]))
|
|
||||||
j++;
|
|
||||||
|
|
||||||
if (i >= j * 2)
|
|
||||||
return 0;
|
|
||||||
|
|
||||||
return 1;
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* a nice mix of characters.
|
|
||||||
*/
|
|
||||||
|
|
||||||
static int simple(const char *newval)
|
|
||||||
{
|
|
||||||
#define digits 1
|
|
||||||
#define uppers 2
|
|
||||||
#define lowers 4
|
|
||||||
#define others 8
|
|
||||||
int c, is_simple = 0;
|
|
||||||
int size;
|
int size;
|
||||||
|
/* check string */
|
||||||
|
int ret = string_checker_helper(p1, p2);
|
||||||
|
/* Make our own copy */
|
||||||
|
char *p = bb_xstrdup(p1);
|
||||||
|
/* reverse string */
|
||||||
|
size = strlen(p);
|
||||||
|
|
||||||
|
while (size--) {
|
||||||
|
*p = p1[size];
|
||||||
|
p++;
|
||||||
|
}
|
||||||
|
/* restore pointer */
|
||||||
|
p -= strlen(p1);
|
||||||
|
/* check reversed string */
|
||||||
|
ret |= string_checker_helper(p, p2);
|
||||||
|
/* clean up */
|
||||||
|
memset(p, 0, strlen(p1));
|
||||||
|
free(p);
|
||||||
|
return ret;
|
||||||
|
}
|
||||||
|
|
||||||
|
#define LOWERCASE 1
|
||||||
|
#define UPPERCASE 2
|
||||||
|
#define NUMBERS 4
|
||||||
|
#define SPECIAL 8
|
||||||
|
|
||||||
|
static const char *obscure_msg(const char *old_p, const char *new_p, const struct passwd *pw)
|
||||||
|
{
|
||||||
int i;
|
int i;
|
||||||
|
int c;
|
||||||
|
int length;
|
||||||
|
int mixed = 0;
|
||||||
|
/* Add 1 for each type of characters to the minlen of password */
|
||||||
|
int size = MINLEN + 8;
|
||||||
|
const char *p;
|
||||||
|
char hostname[255];
|
||||||
|
|
||||||
for (i = 0; (c = *newval++) != 0; i++) {
|
/* size */
|
||||||
if (isdigit(c))
|
if (!new_p || (length = strlen(new_p)) < MINLEN)
|
||||||
is_simple |= digits;
|
return("too short");
|
||||||
else if (isupper(c))
|
|
||||||
is_simple |= uppers;
|
/* no username as-is, as sub-string, reversed, capitalized, doubled */
|
||||||
else if (islower(c))
|
if (string_checker(new_p, pw->pw_name)) {
|
||||||
is_simple |= lowers;
|
return "similar to username";
|
||||||
else
|
}
|
||||||
is_simple |= others;
|
/* no gecos as-is, as sub-string, reversed, capitalized, doubled */
|
||||||
|
if (string_checker(new_p, pw->pw_gecos)) {
|
||||||
|
return "similar to gecos";
|
||||||
|
}
|
||||||
|
/* hostname as-is, as sub-string, reversed, capitalized, doubled */
|
||||||
|
if (gethostname(hostname, 255) == 0) {
|
||||||
|
hostname[254] = '\0';
|
||||||
|
if (string_checker(new_p, hostname)) {
|
||||||
|
return "similar to hostname";
|
||||||
|
}
|
||||||
}
|
}
|
||||||
|
|
||||||
/*
|
/* Should / Must contain a mix of: */
|
||||||
* The scam is this - a password of only one character type
|
for (i = 0; i < length; i++) {
|
||||||
* must be 8 letters long. Two types, 7, and so on.
|
if (islower(new_p[i])) { /* a-z */
|
||||||
*/
|
mixed |= LOWERCASE;
|
||||||
|
} else if (isupper(new_p[i])) { /* A-Z */
|
||||||
|
mixed |= UPPERCASE;
|
||||||
|
} else if (isdigit(new_p[i])) { /* 0-9 */
|
||||||
|
mixed |= NUMBERS;
|
||||||
|
} else { /* special characters */
|
||||||
|
mixed |= SPECIAL;
|
||||||
|
}
|
||||||
|
/* More than 50% similar characters ? */
|
||||||
|
c = 0;
|
||||||
|
p = new_p;
|
||||||
|
while (1) {
|
||||||
|
if ((p = strchr(p, new_p[i])) == NULL) {
|
||||||
|
break;
|
||||||
|
}
|
||||||
|
c++;
|
||||||
|
if (!++p) {
|
||||||
|
break; /* move past the matched char if possible */
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
size = 9;
|
if (c >= (length / 2)) {
|
||||||
if (is_simple & digits)
|
return "too many similar characters";
|
||||||
size--;
|
}
|
||||||
if (is_simple & uppers)
|
|
||||||
size--;
|
|
||||||
if (is_simple & lowers)
|
|
||||||
size--;
|
|
||||||
if (is_simple & others)
|
|
||||||
size--;
|
|
||||||
|
|
||||||
if (size <= i)
|
|
||||||
return 0;
|
|
||||||
|
|
||||||
return 1;
|
|
||||||
#undef digits
|
|
||||||
#undef uppers
|
|
||||||
#undef lowers
|
|
||||||
#undef others
|
|
||||||
}
|
|
||||||
|
|
||||||
static char *str_lower(char *string)
|
|
||||||
{
|
|
||||||
char *cp;
|
|
||||||
|
|
||||||
for (cp = string; *cp; cp++)
|
|
||||||
*cp = tolower(*cp);
|
|
||||||
return string;
|
|
||||||
}
|
|
||||||
|
|
||||||
static const char *
|
|
||||||
password_check(const char *old, const char *newval, const struct passwd *pwdp)
|
|
||||||
{
|
|
||||||
const char *msg;
|
|
||||||
char *newmono, *wrapped;
|
|
||||||
int lenwrap;
|
|
||||||
|
|
||||||
if (strcmp(newval, old) == 0)
|
|
||||||
return "no change";
|
|
||||||
if (simple(newval))
|
|
||||||
return "too simple";
|
|
||||||
|
|
||||||
msg = NULL;
|
|
||||||
newmono = str_lower(bb_xstrdup(newval));
|
|
||||||
lenwrap = strlen(old);
|
|
||||||
wrapped = (char *) xmalloc(lenwrap * 2 + 1);
|
|
||||||
str_lower(strcpy(wrapped, old));
|
|
||||||
|
|
||||||
if (palindrome(newmono))
|
|
||||||
msg = "a palindrome";
|
|
||||||
|
|
||||||
else if (strcmp(wrapped, newmono) == 0)
|
|
||||||
msg = "case changes only";
|
|
||||||
|
|
||||||
else if (similiar(wrapped, newmono))
|
|
||||||
msg = "too similiar";
|
|
||||||
|
|
||||||
else if ( strstr(newval, pwdp->pw_name) )
|
|
||||||
msg = "username in password";
|
|
||||||
|
|
||||||
else {
|
|
||||||
safe_strncpy(wrapped + lenwrap, wrapped, lenwrap + 1);
|
|
||||||
if (strstr(wrapped, newmono))
|
|
||||||
msg = "rotated";
|
|
||||||
}
|
}
|
||||||
|
for(i=0;i<4;i++)
|
||||||
|
if (mixed & (1<<i)) size -= 2;
|
||||||
|
if (length < size)
|
||||||
|
return "too weak";
|
||||||
|
|
||||||
memset(newmono, 0, strlen(newmono));
|
if (old_p && old_p[0] != '\0') {
|
||||||
memset(wrapped, 0, lenwrap * 2);
|
/* check vs. old password */
|
||||||
free(newmono);
|
if (string_checker(new_p, old_p)) {
|
||||||
free(wrapped);
|
return "similar to old password";
|
||||||
|
}
|
||||||
return msg;
|
}
|
||||||
|
return NULL;
|
||||||
}
|
}
|
||||||
|
|
||||||
static const char *
|
|
||||||
obscure_msg(const char *old, const char *newval, const struct passwd *pwdp)
|
|
||||||
{
|
|
||||||
int maxlen, oldlen, newlen;
|
|
||||||
char *new1, *old1;
|
|
||||||
const char *msg;
|
|
||||||
|
|
||||||
oldlen = strlen(old);
|
|
||||||
newlen = strlen(newval);
|
|
||||||
|
|
||||||
#if 0 /* why not check the password when set for the first time? --marekm */
|
|
||||||
if (old[0] == '\0')
|
|
||||||
/* return (1); */
|
|
||||||
return NULL;
|
|
||||||
#endif
|
|
||||||
|
|
||||||
if (newlen < 5)
|
|
||||||
return "too short";
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Remaining checks are optional.
|
|
||||||
*/
|
|
||||||
/* Not for us -- Sean
|
|
||||||
*if (!getdef_bool("OBSCURE_CHECKS_ENAB"))
|
|
||||||
* return NULL;
|
|
||||||
*/
|
|
||||||
msg = password_check(old, newval, pwdp);
|
|
||||||
if (msg)
|
|
||||||
return msg;
|
|
||||||
|
|
||||||
/* The traditional crypt() truncates passwords to 8 chars. It is
|
|
||||||
possible to circumvent the above checks by choosing an easy
|
|
||||||
8-char password and adding some random characters to it...
|
|
||||||
Example: "password$%^&*123". So check it again, this time
|
|
||||||
truncated to the maximum length. Idea from npasswd. --marekm */
|
|
||||||
|
|
||||||
maxlen = 8;
|
|
||||||
if (oldlen <= maxlen && newlen <= maxlen)
|
|
||||||
return NULL;
|
|
||||||
|
|
||||||
new1 = (char *) bb_xstrdup(newval);
|
|
||||||
old1 = (char *) bb_xstrdup(old);
|
|
||||||
if (newlen > maxlen)
|
|
||||||
new1[maxlen] = '\0';
|
|
||||||
if (oldlen > maxlen)
|
|
||||||
old1[maxlen] = '\0';
|
|
||||||
|
|
||||||
msg = password_check(old1, new1, pwdp);
|
|
||||||
|
|
||||||
memset(new1, 0, newlen);
|
|
||||||
memset(old1, 0, oldlen);
|
|
||||||
free(new1);
|
|
||||||
free(old1);
|
|
||||||
|
|
||||||
return msg;
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Obscure - see if password is obscure enough.
|
|
||||||
*
|
|
||||||
* The programmer is encouraged to add as much complexity to this
|
|
||||||
* routine as desired. Included are some of my favorite ways to
|
|
||||||
* check passwords.
|
|
||||||
*/
|
|
||||||
|
|
||||||
int obscure(const char *old, const char *newval, const struct passwd *pwdp)
|
int obscure(const char *old, const char *newval, const struct passwd *pwdp)
|
||||||
{
|
{
|
||||||
const char *msg = obscure_msg(old, newval, pwdp);
|
const char *msg;
|
||||||
|
|
||||||
/* if (msg) { */
|
if ((msg = obscure_msg(old, newval, pwdp))) {
|
||||||
if (msg != NULL) {
|
|
||||||
printf("Bad password: %s.\n", msg);
|
printf("Bad password: %s.\n", msg);
|
||||||
/* return 0; */
|
/* If user is root warn only */
|
||||||
return 1;
|
return (getuid())? 1 : 0;
|
||||||
}
|
}
|
||||||
/* return 1; */
|
|
||||||
return 0;
|
return 0;
|
||||||
}
|
}
|
||||||
|
|||||||
Loading…
x
Reference in New Issue
Block a user