auth-passwd.c revision 149753
157429Smarkm/* 257429Smarkm * Author: Tatu Ylonen <ylo@cs.hut.fi> 357429Smarkm * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland 457429Smarkm * All rights reserved 557429Smarkm * Password authentication. This file contains the functions to check whether 657429Smarkm * the password is valid for the user. 765674Skris * 865674Skris * As far as I am concerned, the code I have written for this software 965674Skris * can be used freely for any purpose. Any derived versions of this 1065674Skris * software must be clearly marked as such, and if the derived work is 1165674Skris * incompatible with the protocol description in the RFC file, it must be 1265674Skris * called by a name other than "ssh" or "Secure Shell". 1365674Skris * 1465674Skris * Copyright (c) 1999 Dug Song. All rights reserved. 1565674Skris * Copyright (c) 2000 Markus Friedl. All rights reserved. 1665674Skris * 1765674Skris * Redistribution and use in source and binary forms, with or without 1865674Skris * modification, are permitted provided that the following conditions 1965674Skris * are met: 2065674Skris * 1. Redistributions of source code must retain the above copyright 2165674Skris * notice, this list of conditions and the following disclaimer. 2265674Skris * 2. Redistributions in binary form must reproduce the above copyright 2365674Skris * notice, this list of conditions and the following disclaimer in the 2465674Skris * documentation and/or other materials provided with the distribution. 2565674Skris * 2665674Skris * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 2765674Skris * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 2865674Skris * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 2965674Skris * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 3065674Skris * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 3165674Skris * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 3265674Skris * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 3365674Skris * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 3465674Skris * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 3565674Skris * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 3657429Smarkm */ 3757429Smarkm 3857429Smarkm#include "includes.h" 39149753SdesRCSID("$OpenBSD: auth-passwd.c,v 1.34 2005/07/19 15:32:26 otto Exp $"); 4099748SdesRCSID("$FreeBSD: head/crypto/openssh/auth-passwd.c 149753 2005-09-03 07:04:25Z des $"); 4157429Smarkm 4257429Smarkm#include "packet.h" 43147005Sdes#include "buffer.h" 4476262Sgreen#include "log.h" 4557429Smarkm#include "servconf.h" 4676262Sgreen#include "auth.h" 47126277Sdes#include "auth-options.h" 4876262Sgreen 49147005Sdesextern Buffer loginmsg; 50124211Sdesextern ServerOptions options; 51124211Sdes 52147005Sdes#ifdef HAVE_LOGIN_CAP 53147005Sdesextern login_cap_t *lc; 54147005Sdes#endif 55147005Sdes 56147005Sdes 57147005Sdes#define DAY (24L * 60 * 60) /* 1 day in seconds */ 58147005Sdes#define TWO_WEEKS (2L * 7 * DAY) /* 2 weeks in seconds */ 59147005Sdes 60126277Sdesvoid 61126277Sdesdisable_forwarding(void) 62126277Sdes{ 63126277Sdes no_port_forwarding_flag = 1; 64126277Sdes no_agent_forwarding_flag = 1; 65126277Sdes no_x11_forwarding_flag = 1; 66126277Sdes} 67126277Sdes 6857429Smarkm/* 6957429Smarkm * Tries to authenticate the user using password. Returns true if 7057429Smarkm * authentication succeeds. 7157429Smarkm */ 7265674Skrisint 7376262Sgreenauth_password(Authctxt *authctxt, const char *password) 7457429Smarkm{ 7576262Sgreen struct passwd * pw = authctxt->pw; 76147005Sdes int result, ok = authctxt->valid; 77137019Sdes#if defined(USE_SHADOW) && defined(HAS_SHADOW_EXPIRE) 78126277Sdes static int expire_checked = 0; 79137019Sdes#endif 8057429Smarkm 8198941Sdes#ifndef HAVE_CYGWIN 82126277Sdes if (pw->pw_uid == 0 && options.permit_root_login != PERMIT_YES) 83124211Sdes ok = 0; 8498941Sdes#endif 8557429Smarkm if (*password == '\0' && options.permit_empty_passwd == 0) 8657429Smarkm return 0; 87113911Sdes 88126277Sdes#ifdef KRB5 8973400Sassar if (options.kerberos_authentication == 1) { 9092559Sdes int ret = auth_krb5_password(authctxt, password); 9192559Sdes if (ret == 1 || ret == 0) 92124211Sdes return ret && ok; 9357565Smarkm /* Fall back to ordinary passwd authentication. */ 9457565Smarkm } 95126277Sdes#endif 96126277Sdes#ifdef HAVE_CYGWIN 9798941Sdes if (is_winnt) { 9898941Sdes HANDLE hToken = cygwin_logon_user(pw, password); 9998941Sdes 10098941Sdes if (hToken == INVALID_HANDLE_VALUE) 10198941Sdes return 0; 10298941Sdes cygwin_set_impersonation_token(hToken); 103124211Sdes return ok; 10498941Sdes } 105126277Sdes#endif 106137019Sdes#ifdef USE_PAM 107137019Sdes if (options.use_pam) 108137019Sdes return (sshpam_auth_passwd(authctxt, password) && ok); 109137019Sdes#endif 110126277Sdes#if defined(USE_SHADOW) && defined(HAS_SHADOW_EXPIRE) 111126277Sdes if (!expire_checked) { 112126277Sdes expire_checked = 1; 113147005Sdes if (auth_shadow_pwexpired(authctxt)) 114126277Sdes authctxt->force_pwchange = 1; 115126277Sdes } 116126277Sdes#endif 117147005Sdes result = sys_auth_passwd(authctxt, password); 118147005Sdes if (authctxt->force_pwchange) 119147005Sdes disable_forwarding(); 120147005Sdes return (result && ok); 121126277Sdes} 122124211Sdes 123126277Sdes#ifdef BSD_AUTH 124147005Sdesstatic void 125147005Sdeswarn_expiry(Authctxt *authctxt, auth_session_t *as) 126147005Sdes{ 127147005Sdes char buf[256]; 128147005Sdes quad_t pwtimeleft, actimeleft, daysleft, pwwarntime, acwarntime; 129147005Sdes 130147005Sdes pwwarntime = acwarntime = TWO_WEEKS; 131147005Sdes 132147005Sdes pwtimeleft = auth_check_change(as); 133147005Sdes actimeleft = auth_check_expire(as); 134147005Sdes#ifdef HAVE_LOGIN_CAP 135147005Sdes if (authctxt->valid) { 136147005Sdes pwwarntime = login_getcaptime(lc, "password-warn", TWO_WEEKS, 137147005Sdes TWO_WEEKS); 138147005Sdes acwarntime = login_getcaptime(lc, "expire-warn", TWO_WEEKS, 139147005Sdes TWO_WEEKS); 140147005Sdes } 141147005Sdes#endif 142147005Sdes if (pwtimeleft != 0 && pwtimeleft < pwwarntime) { 143147005Sdes daysleft = pwtimeleft / DAY + 1; 144147005Sdes snprintf(buf, sizeof(buf), 145147005Sdes "Your password will expire in %lld day%s.\n", 146147005Sdes daysleft, daysleft == 1 ? "" : "s"); 147147005Sdes buffer_append(&loginmsg, buf, strlen(buf)); 148147005Sdes } 149147005Sdes if (actimeleft != 0 && actimeleft < acwarntime) { 150147005Sdes daysleft = actimeleft / DAY + 1; 151147005Sdes snprintf(buf, sizeof(buf), 152147005Sdes "Your account will expire in %lld day%s.\n", 153147005Sdes daysleft, daysleft == 1 ? "" : "s"); 154147005Sdes buffer_append(&loginmsg, buf, strlen(buf)); 155147005Sdes } 156147005Sdes} 157147005Sdes 158126277Sdesint 159126277Sdessys_auth_passwd(Authctxt *authctxt, const char *password) 160126277Sdes{ 161126277Sdes struct passwd *pw = authctxt->pw; 162126277Sdes auth_session_t *as; 163147005Sdes static int expire_checked = 0; 164124211Sdes 165126277Sdes as = auth_usercheck(pw->pw_name, authctxt->style, "auth-ssh", 166126277Sdes (char *)password); 167149753Sdes if (as == NULL) 168149753Sdes return (0); 169126277Sdes if (auth_getstate(as) & AUTH_PWEXPIRED) { 170126277Sdes auth_close(as); 171126277Sdes disable_forwarding(); 172126277Sdes authctxt->force_pwchange = 1; 173126277Sdes return (1); 174126277Sdes } else { 175147005Sdes if (!expire_checked) { 176147005Sdes expire_checked = 1; 177147005Sdes warn_expiry(authctxt, as); 178147005Sdes } 179126277Sdes return (auth_close(as)); 18057429Smarkm } 181126277Sdes} 182126277Sdes#elif !defined(CUSTOM_SYS_AUTH_PASSWD) 183126277Sdesint 184126277Sdessys_auth_passwd(Authctxt *authctxt, const char *password) 185126277Sdes{ 186126277Sdes struct passwd *pw = authctxt->pw; 187126277Sdes char *encrypted_password; 188126277Sdes 189124211Sdes /* Just use the supplied fake password if authctxt is invalid */ 190124211Sdes char *pw_password = authctxt->valid ? shadow_pw(pw) : pw->pw_passwd; 19198941Sdes 19257429Smarkm /* Check for users with no password. */ 193124211Sdes if (strcmp(pw_password, "") == 0 && strcmp(password, "") == 0) 194126277Sdes return (1); 19598941Sdes 196126277Sdes /* Encrypt the candidate password using the proper salt. */ 197126277Sdes encrypted_password = xcrypt(password, 198126277Sdes (pw_password[0] && pw_password[1]) ? pw_password : "xx"); 19998941Sdes 200126277Sdes /* 201126277Sdes * Authentication is accepted if the encrypted passwords 202126277Sdes * are identical. 203126277Sdes */ 204126277Sdes return (strcmp(encrypted_password, pw_password) == 0); 20557429Smarkm} 206126277Sdes#endif 207