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/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/* plugins/kdb/ldap/libkdb_ldap/lockout.c */
/*
* Copyright (C) 2009 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.
*/
#include <k5-int.h>
#include <kadm5/admin.h>
#include <kdb.h>
#include "kdb_ldap.h"
#include "princ_xdr.h"
#include "ldap_principal.h"
#include "ldap_pwd_policy.h"
#include "ldap_tkt_policy.h"
static krb5_error_code
lookup_lockout_policy(krb5_context context,
krb5_db_entry *entry,
krb5_kvno *pw_max_fail,
krb5_deltat *pw_failcnt_interval,
krb5_deltat *pw_lockout_duration)
{
krb5_tl_data tl_data;
krb5_error_code code;
osa_princ_ent_rec adb;
XDR xdrs;
*pw_max_fail = 0;
*pw_failcnt_interval = 0;
*pw_lockout_duration = 0;
tl_data.tl_data_type = KRB5_TL_KADM_DATA;
code = krb5_dbe_lookup_tl_data(context, entry, &tl_data);
if (code != 0 || tl_data.tl_data_length == 0)
return code;
memset(&adb, 0, sizeof(adb));
code = krb5_lookup_tl_kadm_data(&tl_data, &adb);
if (code != 0)
return code;
if (adb.policy != NULL) {
osa_policy_ent_t policy = NULL;
code = krb5_ldap_get_password_policy(context, adb.policy, &policy);
if (code == 0) {
*pw_max_fail = policy->pw_max_fail;
*pw_failcnt_interval = policy->pw_failcnt_interval;
*pw_lockout_duration = policy->pw_lockout_duration;
}
krb5_ldap_free_password_policy(context, policy);
}
xdrmem_create(&xdrs, NULL, 0, XDR_FREE);
ldap_xdr_osa_princ_ent_rec(&xdrs, &adb);
xdr_destroy(&xdrs);
return 0;
}
/* draft-behera-ldap-password-policy-10.txt 7.1 */
static krb5_boolean
locked_check_p(krb5_context context,
krb5_timestamp stamp,
krb5_kvno max_fail,
krb5_timestamp lockout_duration,
krb5_db_entry *entry)
{
krb5_timestamp unlock_time;
/* If the entry was unlocked since the last failure, it's not locked. */
if (krb5_dbe_lookup_last_admin_unlock(context, entry, &unlock_time) == 0 &&
entry->last_failed <= unlock_time)
return FALSE;
if (max_fail == 0 || entry->fail_auth_count < max_fail)
return FALSE;
if (lockout_duration == 0)
return TRUE; /* principal permanently locked */
return (stamp < entry->last_failed + lockout_duration);
}
krb5_error_code
krb5_ldap_lockout_check_policy(krb5_context context,
krb5_db_entry *entry,
krb5_timestamp stamp)
{
krb5_error_code code;
kdb5_dal_handle *dal_handle;
krb5_ldap_context *ldap_context;
krb5_kvno max_fail = 0;
krb5_deltat failcnt_interval = 0;
krb5_deltat lockout_duration = 0;
SETUP_CONTEXT();
if (ldap_context->disable_lockout)
return 0;
code = lookup_lockout_policy(context, entry, &max_fail,
&failcnt_interval,
&lockout_duration);
if (code != 0)
return code;
if (locked_check_p(context, stamp, max_fail, lockout_duration, entry))
return KRB5KDC_ERR_CLIENT_REVOKED;
return 0;
}
krb5_error_code
krb5_ldap_lockout_audit(krb5_context context,
krb5_db_entry *entry,
krb5_timestamp stamp,
krb5_error_code status)
{
krb5_error_code code;
kdb5_dal_handle *dal_handle;
krb5_ldap_context *ldap_context;
krb5_kvno max_fail = 0;
krb5_deltat failcnt_interval = 0;
krb5_deltat lockout_duration = 0;
krb5_timestamp unlock_time;
SETUP_CONTEXT();
switch (status) {
case 0:
case KRB5KDC_ERR_PREAUTH_FAILED:
case KRB5KRB_AP_ERR_BAD_INTEGRITY:
break;
default:
return 0;
}
if (entry == NULL)
return 0;
if (!ldap_context->disable_lockout) {
code = lookup_lockout_policy(context, entry, &max_fail,
&failcnt_interval,
&lockout_duration);
if (code != 0)
return code;
}
/*
* Don't continue to modify the DB for an already locked account.
* (In most cases, status will be KRB5KDC_ERR_CLIENT_REVOKED, and
* this check is unneeded, but in rare cases, we can fail with an
* integrity error or preauth failure before a policy check.)
*/
if (locked_check_p(context, stamp, max_fail, lockout_duration, entry))
return 0;
entry->mask = 0;
/* Only mark the authentication as successful if the entry
* required preauthentication, otherwise we have no idea. */
if (status == 0 && (entry->attributes & KRB5_KDB_REQUIRES_PRE_AUTH)) {
if (!ldap_context->disable_lockout && entry->fail_auth_count != 0) {
entry->fail_auth_count = 0;
entry->mask |= KADM5_FAIL_AUTH_COUNT;
}
if (!ldap_context->disable_last_success) {
entry->last_success = stamp;
entry->mask |= KADM5_LAST_SUCCESS;
}
} else if (!ldap_context->disable_lockout &&
(status == KRB5KDC_ERR_PREAUTH_FAILED ||
status == KRB5KRB_AP_ERR_BAD_INTEGRITY)) {
if (krb5_dbe_lookup_last_admin_unlock(context, entry,
&unlock_time) == 0 &&
entry->last_failed <= unlock_time) {
/* Reset fail_auth_count after administrative unlock. */
entry->fail_auth_count = 0;
entry->mask |= KADM5_FAIL_AUTH_COUNT;
}
if (failcnt_interval != 0 &&
stamp > entry->last_failed + failcnt_interval) {
/* Reset fail_auth_count after failcnt_interval */
entry->fail_auth_count = 0;
entry->mask |= KADM5_FAIL_AUTH_COUNT;
}
entry->last_failed = stamp;
entry->mask |= KADM5_LAST_FAILED | KADM5_FAIL_AUTH_COUNT_INCREMENT;
}
if (entry->mask) {
code = krb5_ldap_put_principal(context, entry, NULL);
if (code != 0)
return code;
}
return 0;
}
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