/* vi: set sw=4 ts=4: */ /* * Copyright 1989 - 1994, Julianne Frances Haugh <jockgrrl@austin.rr.com> * 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 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 * 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. */ /* * This version of obscure.c contains modifications to support "cracklib" * by Alec Muffet (alec.muffett@uk.sun.com). You must obtain the Cracklib * library source code for this function to operate. */ #include <stdlib.h> #include <stdio.h> #include <string.h> #include <ctype.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 *old, const char *newval) { int i, j; i = strlen(newval); for (j = 0; j < i; j++) if (newval[i - j - 1] != newval[j]) return 0; return 1; } /* * 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 *old, const char *newval) { int digits = 0; int uppers = 0; int lowers = 0; int others = 0; int size; int i; for (i = 0; newval[i]; i++) { if (isdigit(newval[i])) digits++; else if (isupper(newval[i])) uppers++; else if (islower(newval[i])) lowers++; else others++; } /* * The scam is this - a password of only one character type * must be 8 letters long. Two types, 7, and so on. */ size = 9; if (digits) size--; if (uppers) size--; if (lowers) size--; if (others) size--; if (size <= i) return 0; return 1; } static char *str_lower(char *string) { char *cp; for (cp = string; *cp; cp++) *cp = tolower(*cp); return string; } static char *password_check(const char *old, const char *newval, const struct passwd *pwdp) { char *msg = NULL; char *oldmono, *newmono, *wrapped; if (strcmp(newval, old) == 0) return "no change"; newmono = str_lower(xstrdup(newval)); oldmono = str_lower(xstrdup(old)); wrapped = (char *) xmalloc(strlen(oldmono) * 2 + 1); strcpy(wrapped, oldmono); strcat(wrapped, oldmono); if (palindrome(oldmono, newmono)) msg = "a palindrome"; if (!msg && strcmp(oldmono, newmono) == 0) msg = "case changes only"; if (!msg && similiar(oldmono, newmono)) msg = "too similiar"; if (!msg && simple(old, newval)) msg = "too simple"; if (!msg && strstr(wrapped, newmono)) msg = "rotated"; bzero(newmono, strlen(newmono)); bzero(oldmono, strlen(oldmono)); bzero(wrapped, strlen(wrapped)); free(newmono); free(oldmono); free(wrapped); return msg; } static char *obscure_msg(const char *old, const char *newval, const struct passwd *pwdp) { int maxlen, oldlen, newlen; char *new1, *old1, *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 *) xstrdup(newval); old1 = (char *) xstrdup(old); if (newlen > maxlen) new1[maxlen] = '\0'; if (oldlen > maxlen) old1[maxlen] = '\0'; msg = password_check(old1, new1, pwdp); bzero(new1, newlen); bzero(old1, 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. */ extern int obscure(const char *old, const char *newval, const struct passwd *pwdp) { char *msg = obscure_msg(old, newval, pwdp); /* if (msg) { */ if (msg != NULL) { printf("Bad password: %s.\n", msg); /* return 0; */ return 1; } /* return 1; */ return 0; }