215 lines
6.1 KiB
C
215 lines
6.1 KiB
C
/* $OpenBSD: auth-passwd.c,v 1.43 2007/09/21 08:15:29 djm Exp $ */
|
|
/*
|
|
* Author: Tatu Ylonen <ylo@cs.hut.fi>
|
|
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
|
|
* All rights reserved
|
|
* Password authentication. This file contains the functions to check whether
|
|
* the password is valid for the user.
|
|
*
|
|
* As far as I am concerned, the code I have written for this software
|
|
* can be used freely for any purpose. Any derived versions of this
|
|
* software must be clearly marked as such, and if the derived work is
|
|
* incompatible with the protocol description in the RFC file, it must be
|
|
* called by a name other than "ssh" or "Secure Shell".
|
|
*
|
|
* Copyright (c) 1999 Dug Song. All rights reserved.
|
|
* Copyright (c) 2000 Markus Friedl. 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.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 THE AUTHOR 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.
|
|
*/
|
|
|
|
#include "includes.h"
|
|
|
|
#include <sys/types.h>
|
|
|
|
#include <pwd.h>
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
#include <stdarg.h>
|
|
|
|
#include "packet.h"
|
|
#include "buffer.h"
|
|
#include "log.h"
|
|
#include "servconf.h"
|
|
#include "key.h"
|
|
#include "hostfile.h"
|
|
#include "auth.h"
|
|
#include "auth-options.h"
|
|
|
|
extern Buffer loginmsg;
|
|
extern ServerOptions options;
|
|
|
|
#ifdef HAVE_LOGIN_CAP
|
|
extern login_cap_t *lc;
|
|
#endif
|
|
|
|
|
|
#define DAY (24L * 60 * 60) /* 1 day in seconds */
|
|
#define TWO_WEEKS (2L * 7 * DAY) /* 2 weeks in seconds */
|
|
|
|
void
|
|
disable_forwarding(void)
|
|
{
|
|
no_port_forwarding_flag = 1;
|
|
no_agent_forwarding_flag = 1;
|
|
no_x11_forwarding_flag = 1;
|
|
}
|
|
|
|
/*
|
|
* Tries to authenticate the user using password. Returns true if
|
|
* authentication succeeds.
|
|
*/
|
|
int
|
|
auth_password(Authctxt *authctxt, const char *password)
|
|
{
|
|
struct passwd * pw = authctxt->pw;
|
|
int result, ok = authctxt->valid;
|
|
#if defined(USE_SHADOW) && defined(HAS_SHADOW_EXPIRE)
|
|
static int expire_checked = 0;
|
|
#endif
|
|
|
|
#ifndef HAVE_CYGWIN
|
|
if (pw->pw_uid == 0 && options.permit_root_login != PERMIT_YES)
|
|
ok = 0;
|
|
#endif
|
|
if (*password == '\0' && options.permit_empty_passwd == 0)
|
|
return 0;
|
|
|
|
#ifdef KRB5
|
|
if (options.kerberos_authentication == 1) {
|
|
int ret = auth_krb5_password(authctxt, password);
|
|
if (ret == 1 || ret == 0)
|
|
return ret && ok;
|
|
/* Fall back to ordinary passwd authentication. */
|
|
}
|
|
#endif
|
|
#ifdef HAVE_CYGWIN
|
|
{
|
|
HANDLE hToken = cygwin_logon_user(pw, password);
|
|
|
|
if (hToken == INVALID_HANDLE_VALUE)
|
|
return 0;
|
|
cygwin_set_impersonation_token(hToken);
|
|
return ok;
|
|
}
|
|
#endif
|
|
#ifdef USE_PAM
|
|
if (options.use_pam)
|
|
return (sshpam_auth_passwd(authctxt, password) && ok);
|
|
#endif
|
|
#if defined(USE_SHADOW) && defined(HAS_SHADOW_EXPIRE)
|
|
if (!expire_checked) {
|
|
expire_checked = 1;
|
|
if (auth_shadow_pwexpired(authctxt))
|
|
authctxt->force_pwchange = 1;
|
|
}
|
|
#endif
|
|
result = sys_auth_passwd(authctxt, password);
|
|
if (authctxt->force_pwchange)
|
|
disable_forwarding();
|
|
return (result && ok);
|
|
}
|
|
|
|
#ifdef BSD_AUTH
|
|
static void
|
|
warn_expiry(Authctxt *authctxt, auth_session_t *as)
|
|
{
|
|
char buf[256];
|
|
quad_t pwtimeleft, actimeleft, daysleft, pwwarntime, acwarntime;
|
|
|
|
pwwarntime = acwarntime = TWO_WEEKS;
|
|
|
|
pwtimeleft = auth_check_change(as);
|
|
actimeleft = auth_check_expire(as);
|
|
#ifdef HAVE_LOGIN_CAP
|
|
if (authctxt->valid) {
|
|
pwwarntime = login_getcaptime(lc, "password-warn", TWO_WEEKS,
|
|
TWO_WEEKS);
|
|
acwarntime = login_getcaptime(lc, "expire-warn", TWO_WEEKS,
|
|
TWO_WEEKS);
|
|
}
|
|
#endif
|
|
if (pwtimeleft != 0 && pwtimeleft < pwwarntime) {
|
|
daysleft = pwtimeleft / DAY + 1;
|
|
snprintf(buf, sizeof(buf),
|
|
"Your password will expire in %lld day%s.\n",
|
|
daysleft, daysleft == 1 ? "" : "s");
|
|
buffer_append(&loginmsg, buf, strlen(buf));
|
|
}
|
|
if (actimeleft != 0 && actimeleft < acwarntime) {
|
|
daysleft = actimeleft / DAY + 1;
|
|
snprintf(buf, sizeof(buf),
|
|
"Your account will expire in %lld day%s.\n",
|
|
daysleft, daysleft == 1 ? "" : "s");
|
|
buffer_append(&loginmsg, buf, strlen(buf));
|
|
}
|
|
}
|
|
|
|
int
|
|
sys_auth_passwd(Authctxt *authctxt, const char *password)
|
|
{
|
|
struct passwd *pw = authctxt->pw;
|
|
auth_session_t *as;
|
|
static int expire_checked = 0;
|
|
|
|
as = auth_usercheck(pw->pw_name, authctxt->style, "auth-ssh",
|
|
(char *)password);
|
|
if (as == NULL)
|
|
return (0);
|
|
if (auth_getstate(as) & AUTH_PWEXPIRED) {
|
|
auth_close(as);
|
|
disable_forwarding();
|
|
authctxt->force_pwchange = 1;
|
|
return (1);
|
|
} else {
|
|
if (!expire_checked) {
|
|
expire_checked = 1;
|
|
warn_expiry(authctxt, as);
|
|
}
|
|
return (auth_close(as));
|
|
}
|
|
}
|
|
#elif !defined(CUSTOM_SYS_AUTH_PASSWD)
|
|
int
|
|
sys_auth_passwd(Authctxt *authctxt, const char *password)
|
|
{
|
|
struct passwd *pw = authctxt->pw;
|
|
char *encrypted_password;
|
|
|
|
/* Just use the supplied fake password if authctxt is invalid */
|
|
char *pw_password = authctxt->valid ? shadow_pw(pw) : pw->pw_passwd;
|
|
|
|
/* Check for users with no password. */
|
|
if (strcmp(pw_password, "") == 0 && strcmp(password, "") == 0)
|
|
return (1);
|
|
|
|
/* Encrypt the candidate password using the proper salt. */
|
|
encrypted_password = xcrypt(password,
|
|
(pw_password[0] && pw_password[1]) ? pw_password : "xx");
|
|
|
|
/*
|
|
* Authentication is accepted if the encrypted passwords
|
|
* are identical.
|
|
*/
|
|
return (strcmp(encrypted_password, pw_password) == 0);
|
|
}
|
|
#endif
|