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/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/*
* Copyright 1993 OpenVision Technologies, Inc., All Rights Reserved
*
* Copyright (C) 2010 by the Massachusetts Institute of Technology.
* All rights reserved.
*
* Export of this software from the United States of America may
* require a specific license from the United States Government.
* It is the responsibility of any person or organization contemplating
* export to obtain such a license before exporting.
*
* WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
* distribute this software and its documentation for any purpose and
* without fee is hereby granted, provided that the above copyright
* notice appear in all copies and that both that copyright notice and
* this permission notice appear in supporting documentation, and that
* the name of M.I.T. not be used in advertising or publicity pertaining
* to distribution of the software without specific, written prior
* permission. Furthermore if you modify this software you must label
* your software as modified software and not distribute it in such a
* fashion that it might be confused with the original M.I.T. software.
* M.I.T. makes no representations about the suitability of
* this software for any purpose. It is provided "as is" without express
* or implied warranty.
*
*
* Sample password quality plugin which checks for dictionary word combos
*/
#include <krb5.h>
#include <krb5/pwqual_plugin.h>
#include <kadm5/admin.h> /* XXX */
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
typedef struct combo_moddata_st {
char **word_list; /* list of word pointers */
char *word_block; /* actual word data */
size_t word_count; /* number of words */
} *combo_moddata;
static int
word_compare(const void *s1, const void *s2)
{
return (strcasecmp(*(const char **)s1, *(const char **)s2));
}
static krb5_error_code
init_dict(combo_moddata dict, const char *dict_file)
{
int fd;
size_t len, i;
char *p, *t;
struct stat sb;
if (dict_file == NULL)
return 0;
if ((fd = open(dict_file, O_RDONLY)) == -1)
return (errno == ENOENT) ? 0 : errno;
if (fstat(fd, &sb) == -1) {
close(fd);
return errno;
}
if ((dict->word_block = malloc(sb.st_size + 1)) == NULL)
return ENOMEM;
if (read(fd, dict->word_block, sb.st_size) != sb.st_size)
return errno;
(void) close(fd);
dict->word_block[sb.st_size] = '\0';
p = dict->word_block;
len = sb.st_size;
while(len > 0 && (t = memchr(p, '\n', len)) != NULL) {
*t = '\0';
len -= t - p + 1;
p = t + 1;
dict->word_count++;
}
if ((dict->word_list = malloc(dict->word_count * sizeof(char *))) == NULL)
return ENOMEM;
p = dict->word_block;
for (i = 0; i < dict->word_count; i++) {
dict->word_list[i] = p;
p += strlen(p) + 1;
}
qsort(dict->word_list, dict->word_count, sizeof(char *), word_compare);
return 0;
}
static void
destroy_dict(combo_moddata dict)
{
if (dict == NULL)
return;
free(dict->word_list);
free(dict->word_block);
free(dict);
return;
}
static krb5_error_code
combo_open(krb5_context context, const char *dict_file,
krb5_pwqual_moddata *data)
{
krb5_error_code ret;
combo_moddata dict;
*data = NULL;
/* Allocate and initialize a dictionary structure. */
dict = malloc(sizeof(*dict));
if (dict == NULL)
return ENOMEM;
dict->word_list = NULL;
dict->word_block = NULL;
dict->word_count = 0;
/* Fill in the dictionary structure with data from dict_file. */
ret = init_dict(dict, dict_file);
if (ret != 0) {
destroy_dict(dict);
return ret;
}
*data = (krb5_pwqual_moddata)dict;
return 0;
}
static krb5_error_code
combo_check(krb5_context context, krb5_pwqual_moddata data,
const char *password, const char *policy_name,
krb5_principal princ)
{
combo_moddata dict = (combo_moddata)data;
size_t i, j, len, pwlen;
const char *remainder;
if (dict->word_list == NULL)
return 0;
pwlen = strlen(password);
for (i = 0; i < dict->word_count; i++) {
len = strlen(dict->word_list[i]);
if (len >= pwlen)
continue;
if (strncasecmp(password, dict->word_list[i], len) != 0)
continue;
remainder = password + len;
for (i = 0; i < dict->word_count; i++) {
if (strcasecmp(remainder, dict->word_list[i]) == 0)
return KADM5_PASS_Q_DICT;
}
}
return 0;
}
static void
combo_close(krb5_context context, krb5_pwqual_moddata data)
{
destroy_dict((combo_moddata)data);
}
krb5_error_code
pwqual_combo_initvt(krb5_context context, int maj_ver, int min_ver,
krb5_plugin_vtable vtable)
{
krb5_pwqual_vtable vt;
if (maj_ver != 1)
return KRB5_PLUGIN_VER_NOTSUPP;
vt = (krb5_pwqual_vtable)vtable;
vt->open = combo_open;
vt->check = combo_check;
vt->close = combo_close;
return 0;
}
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