1 /* 2 * Author: Tatu Ylonen <ylo@cs.hut.fi> 3 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland 4 * All rights reserved 5 * Password authentication. This file contains the functions to check whether 6 * the password is valid for the user. 7 * 8 * As far as I am concerned, the code I have written for this software 9 * can be used freely for any purpose. Any derived versions of this 10 * software must be clearly marked as such, and if the derived work is 11 * incompatible with the protocol description in the RFC file, it must be 12 * called by a name other than "ssh" or "Secure Shell". 13 * 14 * Copyright (c) 1999 Dug Song. All rights reserved. 15 * Copyright (c) 2000 Markus Friedl. All rights reserved. 16 * 17 * Redistribution and use in source and binary forms, with or without 18 * modification, are permitted provided that the following conditions 19 * are met: 20 * 1. Redistributions of source code must retain the above copyright 21 * notice, this list of conditions and the following disclaimer. 22 * 2. Redistributions in binary form must reproduce the above copyright 23 * notice, this list of conditions and the following disclaimer in the 24 * documentation and/or other materials provided with the distribution. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 27 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 28 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 29 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 30 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 31 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 35 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 36 */ 37 38 #include "includes.h" 39 RCSID("$OpenBSD: auth-passwd.c,v 1.27 2002/05/24 16:45:16 stevesk Exp $"); 40 41 #include "packet.h" 42 #include "log.h" 43 #include "servconf.h" 44 #include "auth.h" 45 46 #if !defined(USE_PAM) && !defined(HAVE_OSF_SIA) 47 /* Don't need any of these headers for the PAM or SIA cases */ 48 # ifdef HAVE_CRYPT_H 49 # include <crypt.h> 50 # endif 51 # ifdef WITH_AIXAUTHENTICATE 52 # include <login.h> 53 # endif 54 # ifdef __hpux 55 # include <hpsecurity.h> 56 # include <prot.h> 57 # endif 58 # if defined(HAVE_SHADOW_H) && !defined(DISABLE_SHADOW) 59 # include <shadow.h> 60 # endif 61 # if defined(HAVE_GETPWANAM) && !defined(DISABLE_SHADOW) 62 # include <sys/label.h> 63 # include <sys/audit.h> 64 # include <pwdadj.h> 65 # endif 66 # if defined(HAVE_MD5_PASSWORDS) && !defined(HAVE_MD5_CRYPT) 67 # include "md5crypt.h" 68 # endif /* defined(HAVE_MD5_PASSWORDS) && !defined(HAVE_MD5_CRYPT) */ 69 70 # ifdef HAVE_CYGWIN 71 # undef ERROR 72 # include <windows.h> 73 # include <sys/cygwin.h> 74 # define is_winnt (GetVersion() < 0x80000000) 75 # endif 76 #endif /* !USE_PAM && !HAVE_OSF_SIA */ 77 78 extern ServerOptions options; 79 #ifdef WITH_AIXAUTHENTICATE 80 extern char *aixloginmsg; 81 #endif 82 83 /* 84 * Tries to authenticate the user using password. Returns true if 85 * authentication succeeds. 86 */ 87 int 88 auth_password(Authctxt *authctxt, const char *password) 89 { 90 #if defined(USE_PAM) 91 if (*password == '\0' && options.permit_empty_passwd == 0) 92 return 0; 93 return auth_pam_password(authctxt, password); 94 #elif defined(HAVE_OSF_SIA) 95 if (*password == '\0' && options.permit_empty_passwd == 0) 96 return 0; 97 return auth_sia_password(authctxt, password); 98 #else 99 struct passwd * pw = authctxt->pw; 100 char *encrypted_password; 101 char *pw_password; 102 char *salt; 103 #if defined(HAVE_SHADOW_H) && !defined(DISABLE_SHADOW) 104 struct spwd *spw; 105 #endif 106 #if defined(HAVE_GETPWANAM) && !defined(DISABLE_SHADOW) 107 struct passwd_adjunct *spw; 108 #endif 109 #ifdef WITH_AIXAUTHENTICATE 110 char *authmsg; 111 int authsuccess; 112 int reenter = 1; 113 #endif 114 115 /* deny if no user. */ 116 if (pw == NULL) 117 return 0; 118 #ifndef HAVE_CYGWIN 119 if (pw->pw_uid == 0 && options.permit_root_login != PERMIT_YES) 120 return 0; 121 #endif 122 if (*password == '\0' && options.permit_empty_passwd == 0) 123 return 0; 124 #ifdef KRB5 125 if (options.kerberos_authentication == 1) { 126 int ret = auth_krb5_password(authctxt, password); 127 if (ret == 1 || ret == 0) 128 return ret; 129 /* Fall back to ordinary passwd authentication. */ 130 } 131 #endif 132 #ifdef HAVE_CYGWIN 133 if (is_winnt) { 134 HANDLE hToken = cygwin_logon_user(pw, password); 135 136 if (hToken == INVALID_HANDLE_VALUE) 137 return 0; 138 cygwin_set_impersonation_token(hToken); 139 return 1; 140 } 141 #endif 142 #ifdef WITH_AIXAUTHENTICATE 143 authsuccess = (authenticate(pw->pw_name,password,&reenter,&authmsg) == 0); 144 145 if (authsuccess) 146 /* We don't have a pty yet, so just label the line as "ssh" */ 147 if (loginsuccess(authctxt->user, 148 get_canonical_hostname(options.verify_reverse_mapping), 149 "ssh", &aixloginmsg) < 0) 150 aixloginmsg = NULL; 151 152 return(authsuccess); 153 #endif 154 #ifdef KRB4 155 if (options.kerberos_authentication == 1) { 156 int ret = auth_krb4_password(authctxt, password); 157 if (ret == 1 || ret == 0) 158 return ret; 159 /* Fall back to ordinary passwd authentication. */ 160 } 161 #endif 162 #ifdef BSD_AUTH 163 if (auth_userokay(pw->pw_name, authctxt->style, "auth-ssh", 164 (char *)password) == 0) 165 return 0; 166 else 167 return 1; 168 #endif 169 pw_password = pw->pw_passwd; 170 171 /* 172 * Various interfaces to shadow or protected password data 173 */ 174 #if defined(HAVE_SHADOW_H) && !defined(DISABLE_SHADOW) 175 spw = getspnam(pw->pw_name); 176 if (spw != NULL) 177 pw_password = spw->sp_pwdp; 178 #endif /* defined(HAVE_SHADOW_H) && !defined(DISABLE_SHADOW) */ 179 180 #if defined(HAVE_GETPWANAM) && !defined(DISABLE_SHADOW) 181 if (issecure() && (spw = getpwanam(pw->pw_name)) != NULL) 182 pw_password = spw->pwa_passwd; 183 #endif /* defined(HAVE_GETPWANAM) && !defined(DISABLE_SHADOW) */ 184 185 /* Check for users with no password. */ 186 if ((password[0] == '\0') && (pw_password[0] == '\0')) 187 return 1; 188 189 if (pw_password[0] != '\0') 190 salt = pw_password; 191 else 192 salt = "xx"; 193 194 #ifdef HAVE_MD5_PASSWORDS 195 if (is_md5_salt(salt)) 196 encrypted_password = md5_crypt(password, salt); 197 else 198 encrypted_password = crypt(password, salt); 199 #else /* HAVE_MD5_PASSWORDS */ 200 encrypted_password = crypt(password, salt); 201 #endif /* HAVE_MD5_PASSWORDS */ 202 203 /* Authentication is accepted if the encrypted passwords are identical. */ 204 return (strcmp(encrypted_password, pw_password) == 0); 205 #endif /* !USE_PAM && !HAVE_OSF_SIA */ 206 } 207