xref: /titanic_41/usr/src/cmd/ssh/sshd/auth-passwd.c (revision 4bff34e37def8a90f9194d81bc345c52ba20086a)
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 #pragma ident	"%Z%%M%	%I%	%E% SMI"
42 
43 #include "packet.h"
44 #include "log.h"
45 #include "servconf.h"
46 #include "auth.h"
47 
48 #if !defined(USE_PAM) && !defined(HAVE_OSF_SIA)
49 /* Don't need any of these headers for the PAM or SIA cases */
50 # ifdef HAVE_CRYPT_H
51 #  include <crypt.h>
52 # endif
53 # ifdef WITH_AIXAUTHENTICATE
54 #  include <login.h>
55 # endif
56 # ifdef __hpux
57 #  include <hpsecurity.h>
58 #  include <prot.h>
59 # endif
60 # ifdef HAVE_SECUREWARE
61 #  include <sys/security.h>
62 #  include <sys/audit.h>
63 #  include <prot.h>
64 # endif /* HAVE_SECUREWARE */
65 # if defined(HAVE_SHADOW_H) && !defined(DISABLE_SHADOW)
66 #  include <shadow.h>
67 # endif
68 # if defined(HAVE_GETPWANAM) && !defined(DISABLE_SHADOW)
69 #  include <sys/label.h>
70 #  include <sys/audit.h>
71 #  include <pwdadj.h>
72 # endif
73 # if defined(HAVE_MD5_PASSWORDS) && !defined(HAVE_MD5_CRYPT)
74 #  include "md5crypt.h"
75 # endif /* defined(HAVE_MD5_PASSWORDS) && !defined(HAVE_MD5_CRYPT) */
76 
77 # ifdef HAVE_CYGWIN
78 #  undef ERROR
79 #  include <windows.h>
80 #  include <sys/cygwin.h>
81 #  define is_winnt       (GetVersion() < 0x80000000)
82 # endif
83 #endif /* !USE_PAM && !HAVE_OSF_SIA */
84 
85 extern ServerOptions options;
86 #ifdef WITH_AIXAUTHENTICATE
87 extern char *aixloginmsg;
88 #endif
89 
90 /*
91  * Tries to authenticate the user using password.  Returns true if
92  * authentication succeeds.
93  */
94 int
95 auth_password(Authctxt *authctxt, const char *password)
96 {
97 #if defined(USE_PAM)
98 	if (*password == '\0' && options.permit_empty_passwd == 0)
99 		return 0;
100 	return auth_pam_password(authctxt, password);
101 #elif defined(HAVE_OSF_SIA)
102 	if (*password == '\0' && options.permit_empty_passwd == 0)
103 		return 0;
104 	return auth_sia_password(authctxt, password);
105 #else
106 	struct passwd * pw = authctxt->pw;
107 	char *encrypted_password;
108 	char *pw_password;
109 	char *salt;
110 #if defined(__hpux) || defined(HAVE_SECUREWARE)
111 	struct pr_passwd *spw;
112 #endif /* __hpux || HAVE_SECUREWARE */
113 #if defined(HAVE_SHADOW_H) && !defined(DISABLE_SHADOW)
114 	struct spwd *spw;
115 #endif
116 #if defined(HAVE_GETPWANAM) && !defined(DISABLE_SHADOW)
117 	struct passwd_adjunct *spw;
118 #endif
119 #ifdef WITH_AIXAUTHENTICATE
120 	char *authmsg;
121 	int authsuccess;
122 	int reenter = 1;
123 #endif
124 
125 	/* deny if no user. */
126 	if (pw == NULL)
127 		return 0;
128 #ifndef HAVE_CYGWIN
129        if (pw->pw_uid == 0 && options.permit_root_login != PERMIT_YES)
130 		return 0;
131 #endif
132 	if (*password == '\0' && options.permit_empty_passwd == 0)
133 		return 0;
134 #ifdef KRB5
135 	if (options.kerberos_authentication == 1) {
136 		int ret = auth_krb5_password(authctxt, password);
137 		if (ret == 1 || ret == 0)
138 			return ret;
139 		/* Fall back to ordinary passwd authentication. */
140 	}
141 #endif
142 #ifdef HAVE_CYGWIN
143 	if (is_winnt) {
144 		HANDLE hToken = cygwin_logon_user(pw, password);
145 
146 		if (hToken == INVALID_HANDLE_VALUE)
147 			return 0;
148 		cygwin_set_impersonation_token(hToken);
149 		return 1;
150 	}
151 #endif
152 #ifdef WITH_AIXAUTHENTICATE
153 	authsuccess = (authenticate(pw->pw_name,password,&reenter,&authmsg) == 0);
154 
155 	if (authsuccess)
156 	        /* We don't have a pty yet, so just label the line as "ssh" */
157 	        if (loginsuccess(authctxt->user,
158 			get_canonical_hostname(options.verify_reverse_mapping),
159 			"ssh", &aixloginmsg) < 0)
160 				aixloginmsg = NULL;
161 
162 	return(authsuccess);
163 #endif
164 #ifdef KRB4
165 	if (options.kerberos_authentication == 1) {
166 		int ret = auth_krb4_password(authctxt, password);
167 		if (ret == 1 || ret == 0)
168 			return ret;
169 		/* Fall back to ordinary passwd authentication. */
170 	}
171 #endif
172 #ifdef BSD_AUTH
173 	if (auth_userokay(pw->pw_name, authctxt->style, "auth-ssh",
174 	    (char *)password) == 0)
175 		return 0;
176 	else
177 		return 1;
178 #endif
179 	pw_password = pw->pw_passwd;
180 
181 	/*
182 	 * Various interfaces to shadow or protected password data
183 	 */
184 #if defined(HAVE_SHADOW_H) && !defined(DISABLE_SHADOW)
185 	spw = getspnam(pw->pw_name);
186 	if (spw != NULL)
187 		pw_password = spw->sp_pwdp;
188 #endif /* defined(HAVE_SHADOW_H) && !defined(DISABLE_SHADOW) */
189 
190 #if defined(HAVE_GETPWANAM) && !defined(DISABLE_SHADOW)
191 	if (issecure() && (spw = getpwanam(pw->pw_name)) != NULL)
192 		pw_password = spw->pwa_passwd;
193 #endif /* defined(HAVE_GETPWANAM) && !defined(DISABLE_SHADOW) */
194 
195 #ifdef HAVE_SECUREWARE
196 	if ((spw = getprpwnam(pw->pw_name)) != NULL)
197 		pw_password = spw->ufld.fd_encrypt;
198 #endif /* HAVE_SECUREWARE */
199 
200 #if defined(__hpux) && !defined(HAVE_SECUREWARE)
201 	if (iscomsec() && (spw = getprpwnam(pw->pw_name)) != NULL)
202 		pw_password = spw->ufld.fd_encrypt;
203 #endif /* defined(__hpux) && !defined(HAVE_SECUREWARE) */
204 
205 	/* Check for users with no password. */
206 	if ((password[0] == '\0') && (pw_password[0] == '\0'))
207 		return 1;
208 
209 	if (pw_password[0] != '\0')
210 		salt = pw_password;
211 	else
212 		salt = "xx";
213 
214 #ifdef HAVE_MD5_PASSWORDS
215 	if (is_md5_salt(salt))
216 		encrypted_password = md5_crypt(password, salt);
217 	else
218 		encrypted_password = crypt(password, salt);
219 #else /* HAVE_MD5_PASSWORDS */
220 # if defined(__hpux) && !defined(HAVE_SECUREWARE)
221 	if (iscomsec())
222 		encrypted_password = bigcrypt(password, salt);
223 	else
224 		encrypted_password = crypt(password, salt);
225 # else
226 #  ifdef HAVE_SECUREWARE
227 	encrypted_password = bigcrypt(password, salt);
228 #  else
229 	encrypted_password = crypt(password, salt);
230 #  endif /* HAVE_SECUREWARE */
231 # endif /* __hpux && !defined(HAVE_SECUREWARE) */
232 #endif /* HAVE_MD5_PASSWORDS */
233 
234 	/* Authentication is accepted if the encrypted passwords are identical. */
235 	return (strcmp(encrypted_password, pw_password) == 0);
236 #endif /* !USE_PAM && !HAVE_OSF_SIA */
237 }
238