auth-passwd.c revision 162856
1162856Sdes/* $OpenBSD: auth-passwd.c,v 1.40 2006/08/03 03:34:41 deraadt Exp $ */ 257429Smarkm/* 357429Smarkm * Author: Tatu Ylonen <ylo@cs.hut.fi> 457429Smarkm * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland 557429Smarkm * All rights reserved 657429Smarkm * Password authentication. This file contains the functions to check whether 757429Smarkm * the password is valid for the user. 865674Skris * 965674Skris * As far as I am concerned, the code I have written for this software 1065674Skris * can be used freely for any purpose. Any derived versions of this 1165674Skris * software must be clearly marked as such, and if the derived work is 1265674Skris * incompatible with the protocol description in the RFC file, it must be 1365674Skris * called by a name other than "ssh" or "Secure Shell". 1465674Skris * 1565674Skris * Copyright (c) 1999 Dug Song. All rights reserved. 1665674Skris * Copyright (c) 2000 Markus Friedl. All rights reserved. 1765674Skris * 1865674Skris * Redistribution and use in source and binary forms, with or without 1965674Skris * modification, are permitted provided that the following conditions 2065674Skris * are met: 2165674Skris * 1. Redistributions of source code must retain the above copyright 2265674Skris * notice, this list of conditions and the following disclaimer. 2365674Skris * 2. Redistributions in binary form must reproduce the above copyright 2465674Skris * notice, this list of conditions and the following disclaimer in the 2565674Skris * documentation and/or other materials provided with the distribution. 2665674Skris * 2765674Skris * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 2865674Skris * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 2965674Skris * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 3065674Skris * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 3165674Skris * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 3265674Skris * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 3365674Skris * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 3465674Skris * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 3565674Skris * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 3665674Skris * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 3757429Smarkm */ 3857429Smarkm 3957429Smarkm#include "includes.h" 40162856Sdes__RCSID("$FreeBSD: head/crypto/openssh/auth-passwd.c 162856 2006-09-30 13:38:06Z des $"); 4157429Smarkm 42162856Sdes#include <sys/types.h> 43162856Sdes 44162856Sdes#include <pwd.h> 45162856Sdes#include <stdio.h> 46162856Sdes#include <string.h> 47162856Sdes#include <stdarg.h> 48162856Sdes 4957429Smarkm#include "packet.h" 50147005Sdes#include "buffer.h" 5176262Sgreen#include "log.h" 5257429Smarkm#include "servconf.h" 53162856Sdes#include "key.h" 54162856Sdes#include "hostfile.h" 5576262Sgreen#include "auth.h" 56126277Sdes#include "auth-options.h" 5776262Sgreen 58147005Sdesextern Buffer loginmsg; 59124211Sdesextern ServerOptions options; 60124211Sdes 61147005Sdes#ifdef HAVE_LOGIN_CAP 62147005Sdesextern login_cap_t *lc; 63147005Sdes#endif 64147005Sdes 65147005Sdes 66147005Sdes#define DAY (24L * 60 * 60) /* 1 day in seconds */ 67147005Sdes#define TWO_WEEKS (2L * 7 * DAY) /* 2 weeks in seconds */ 68147005Sdes 69126277Sdesvoid 70126277Sdesdisable_forwarding(void) 71126277Sdes{ 72126277Sdes no_port_forwarding_flag = 1; 73126277Sdes no_agent_forwarding_flag = 1; 74126277Sdes no_x11_forwarding_flag = 1; 75126277Sdes} 76126277Sdes 7757429Smarkm/* 7857429Smarkm * Tries to authenticate the user using password. Returns true if 7957429Smarkm * authentication succeeds. 8057429Smarkm */ 8165674Skrisint 8276262Sgreenauth_password(Authctxt *authctxt, const char *password) 8357429Smarkm{ 8476262Sgreen struct passwd * pw = authctxt->pw; 85147005Sdes int result, ok = authctxt->valid; 86137019Sdes#if defined(USE_SHADOW) && defined(HAS_SHADOW_EXPIRE) 87126277Sdes static int expire_checked = 0; 88137019Sdes#endif 8957429Smarkm 9098941Sdes#ifndef HAVE_CYGWIN 91126277Sdes if (pw->pw_uid == 0 && options.permit_root_login != PERMIT_YES) 92124211Sdes ok = 0; 9398941Sdes#endif 9457429Smarkm if (*password == '\0' && options.permit_empty_passwd == 0) 9557429Smarkm return 0; 96113911Sdes 97126277Sdes#ifdef KRB5 9873400Sassar if (options.kerberos_authentication == 1) { 9992559Sdes int ret = auth_krb5_password(authctxt, password); 10092559Sdes if (ret == 1 || ret == 0) 101124211Sdes return ret && ok; 10257565Smarkm /* Fall back to ordinary passwd authentication. */ 10357565Smarkm } 104126277Sdes#endif 105126277Sdes#ifdef HAVE_CYGWIN 10698941Sdes if (is_winnt) { 10798941Sdes HANDLE hToken = cygwin_logon_user(pw, password); 10898941Sdes 10998941Sdes if (hToken == INVALID_HANDLE_VALUE) 11098941Sdes return 0; 11198941Sdes cygwin_set_impersonation_token(hToken); 112124211Sdes return ok; 11398941Sdes } 114126277Sdes#endif 115137019Sdes#ifdef USE_PAM 116137019Sdes if (options.use_pam) 117137019Sdes return (sshpam_auth_passwd(authctxt, password) && ok); 118137019Sdes#endif 119126277Sdes#if defined(USE_SHADOW) && defined(HAS_SHADOW_EXPIRE) 120126277Sdes if (!expire_checked) { 121126277Sdes expire_checked = 1; 122147005Sdes if (auth_shadow_pwexpired(authctxt)) 123126277Sdes authctxt->force_pwchange = 1; 124126277Sdes } 125126277Sdes#endif 126147005Sdes result = sys_auth_passwd(authctxt, password); 127147005Sdes if (authctxt->force_pwchange) 128147005Sdes disable_forwarding(); 129147005Sdes return (result && ok); 130126277Sdes} 131124211Sdes 132126277Sdes#ifdef BSD_AUTH 133147005Sdesstatic void 134147005Sdeswarn_expiry(Authctxt *authctxt, auth_session_t *as) 135147005Sdes{ 136147005Sdes char buf[256]; 137147005Sdes quad_t pwtimeleft, actimeleft, daysleft, pwwarntime, acwarntime; 138147005Sdes 139147005Sdes pwwarntime = acwarntime = TWO_WEEKS; 140147005Sdes 141147005Sdes pwtimeleft = auth_check_change(as); 142147005Sdes actimeleft = auth_check_expire(as); 143147005Sdes#ifdef HAVE_LOGIN_CAP 144147005Sdes if (authctxt->valid) { 145147005Sdes pwwarntime = login_getcaptime(lc, "password-warn", TWO_WEEKS, 146147005Sdes TWO_WEEKS); 147147005Sdes acwarntime = login_getcaptime(lc, "expire-warn", TWO_WEEKS, 148147005Sdes TWO_WEEKS); 149147005Sdes } 150147005Sdes#endif 151147005Sdes if (pwtimeleft != 0 && pwtimeleft < pwwarntime) { 152147005Sdes daysleft = pwtimeleft / DAY + 1; 153147005Sdes snprintf(buf, sizeof(buf), 154147005Sdes "Your password will expire in %lld day%s.\n", 155147005Sdes daysleft, daysleft == 1 ? "" : "s"); 156147005Sdes buffer_append(&loginmsg, buf, strlen(buf)); 157147005Sdes } 158147005Sdes if (actimeleft != 0 && actimeleft < acwarntime) { 159147005Sdes daysleft = actimeleft / DAY + 1; 160147005Sdes snprintf(buf, sizeof(buf), 161147005Sdes "Your account will expire in %lld day%s.\n", 162147005Sdes daysleft, daysleft == 1 ? "" : "s"); 163147005Sdes buffer_append(&loginmsg, buf, strlen(buf)); 164147005Sdes } 165147005Sdes} 166147005Sdes 167126277Sdesint 168126277Sdessys_auth_passwd(Authctxt *authctxt, const char *password) 169126277Sdes{ 170126277Sdes struct passwd *pw = authctxt->pw; 171126277Sdes auth_session_t *as; 172147005Sdes static int expire_checked = 0; 173124211Sdes 174126277Sdes as = auth_usercheck(pw->pw_name, authctxt->style, "auth-ssh", 175126277Sdes (char *)password); 176149753Sdes if (as == NULL) 177149753Sdes return (0); 178126277Sdes if (auth_getstate(as) & AUTH_PWEXPIRED) { 179126277Sdes auth_close(as); 180126277Sdes disable_forwarding(); 181126277Sdes authctxt->force_pwchange = 1; 182126277Sdes return (1); 183126277Sdes } else { 184147005Sdes if (!expire_checked) { 185147005Sdes expire_checked = 1; 186147005Sdes warn_expiry(authctxt, as); 187147005Sdes } 188126277Sdes return (auth_close(as)); 18957429Smarkm } 190126277Sdes} 191126277Sdes#elif !defined(CUSTOM_SYS_AUTH_PASSWD) 192126277Sdesint 193126277Sdessys_auth_passwd(Authctxt *authctxt, const char *password) 194126277Sdes{ 195126277Sdes struct passwd *pw = authctxt->pw; 196126277Sdes char *encrypted_password; 197126277Sdes 198124211Sdes /* Just use the supplied fake password if authctxt is invalid */ 199124211Sdes char *pw_password = authctxt->valid ? shadow_pw(pw) : pw->pw_passwd; 20098941Sdes 20157429Smarkm /* Check for users with no password. */ 202124211Sdes if (strcmp(pw_password, "") == 0 && strcmp(password, "") == 0) 203126277Sdes return (1); 20498941Sdes 205126277Sdes /* Encrypt the candidate password using the proper salt. */ 206126277Sdes encrypted_password = xcrypt(password, 207126277Sdes (pw_password[0] && pw_password[1]) ? pw_password : "xx"); 20898941Sdes 209126277Sdes /* 210126277Sdes * Authentication is accepted if the encrypted passwords 211126277Sdes * are identical. 212126277Sdes */ 213126277Sdes return (strcmp(encrypted_password, pw_password) == 0); 21457429Smarkm} 215126277Sdes#endif 216