2 * Copyright (c) 1997 - 2005 Kungliga Tekniska Högskolan
3 * (Royal Institute of Technology, Stockholm, Sweden).
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of the Institute nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 #include "krb5_locl.h"
39 /* see if principal is mentioned in the filename access file, return
40 TRUE (in result) if so, FALSE otherwise */
42 static krb5_error_code
43 check_one_file(krb5_context context
,
46 krb5_principal principal
,
56 f
= fopen (filename
, "r");
61 /* check type and mode of file */
62 if (fstat(fileno(f
), &st
) != 0) {
66 if (S_ISDIR(st
.st_mode
)) {
70 if (st
.st_uid
!= pwd
->pw_uid
&& st
.st_uid
!= 0) {
74 if ((st
.st_mode
& (S_IWGRP
| S_IWOTH
)) != 0) {
79 while (fgets (buf
, sizeof(buf
), f
) != NULL
) {
81 char *newline
= buf
+ strcspn(buf
, "\n");
83 if(*newline
!= '\n') {
87 while(c
!= EOF
&& c
!= '\n')
89 /* line was too long, so ignore it */
94 ret
= krb5_parse_name (context
, buf
, &tmp
);
97 *result
= krb5_principal_compare (context
, principal
, tmp
);
98 krb5_free_principal (context
, tmp
);
108 static krb5_error_code
109 check_directory(krb5_context context
,
112 krb5_principal principal
,
113 krb5_boolean
*result
)
117 char filename
[MAXPATHLEN
];
118 krb5_error_code ret
= 0;
123 if(lstat(dirname
, &st
) < 0)
126 if (!S_ISDIR(st
.st_mode
))
129 if (st
.st_uid
!= pwd
->pw_uid
&& st
.st_uid
!= 0)
131 if ((st
.st_mode
& (S_IWGRP
| S_IWOTH
)) != 0)
134 if((d
= opendir(dirname
)) == NULL
)
142 if(fstat(fd
, &st2
) < 0) {
146 if(st
.st_dev
!= st2
.st_dev
|| st
.st_ino
!= st2
.st_ino
) {
152 while((dent
= readdir(d
)) != NULL
) {
153 if(strcmp(dent
->d_name
, ".") == 0 ||
154 strcmp(dent
->d_name
, "..") == 0 ||
155 dent
->d_name
[0] == '#' || /* emacs autosave */
156 dent
->d_name
[strlen(dent
->d_name
) - 1] == '~') /* emacs backup */
158 snprintf(filename
, sizeof(filename
), "%s/%s", dirname
, dent
->d_name
);
159 ret
= check_one_file(context
, filename
, pwd
, principal
, result
);
160 if(ret
== 0 && *result
== TRUE
)
162 ret
= 0; /* don't propagate errors upstream */
171 match_local_principals(krb5_context context
,
172 krb5_principal principal
,
176 krb5_realm
*realms
, *r
;
177 krb5_boolean result
= FALSE
;
179 /* multi-component principals can never match */
180 if(krb5_principal_get_comp_string(context
, principal
, 1) != NULL
)
183 ret
= krb5_get_default_realms (context
, &realms
);
187 for (r
= realms
; *r
!= NULL
; ++r
) {
188 if(strcmp(krb5_principal_get_realm(context
, principal
),
191 if(strcmp(krb5_principal_get_comp_string(context
, principal
, 0),
197 krb5_free_host_realm (context
, realms
);
202 * This function takes the name of a local user and checks if
203 * principal is allowed to log in as that user.
205 * The user may have a ~/.k5login file listing principals that are
206 * allowed to login as that user. If that file does not exist, all
207 * principals with a first component identical to the username, and a
208 * realm considered local, are allowed access.
210 * The .k5login file must contain one principal per line, be owned by
211 * user and not be writable by group or other (but must be readable by
214 * Note that if the file exists, no implicit access rights are given
215 * to user@@LOCALREALM.
217 * Optionally, a set of files may be put in ~/.k5login.d (a
218 * directory), in which case they will all be checked in the same
219 * manner as .k5login. The files may be called anything, but files
220 * starting with a hash (#) , or ending with a tilde (~) are
221 * ignored. Subdirectories are not traversed. Note that this directory
222 * may not be checked by other Kerberos implementations.
224 * If no configuration file exists, match user against local domains,
225 * ie luser@@LOCAL-REALMS-IN-CONFIGURATION-FILES.
227 * @param context Kerberos 5 context.
228 * @param principal principal to check if allowed to login
229 * @param luser local user id
231 * @return returns TRUE if access should be granted, FALSE otherwise.
233 * @ingroup krb5_support
236 KRB5_LIB_FUNCTION krb5_boolean KRB5_LIB_CALL
237 krb5_kuserok (krb5_context context
,
238 krb5_principal principal
,
244 struct passwd
*pwd
= NULL
;
245 char *profile_dir
= NULL
;
247 krb5_boolean result
= FALSE
;
249 krb5_boolean found_file
= FALSE
;
251 #ifdef POSIX_GETPWNAM_R
255 if(getpwnam_r(luser
, &pw
, pwbuf
, sizeof(pwbuf
), &pwd
) != 0)
258 pwd
= getpwnam (luser
);
262 profile_dir
= pwd
->pw_dir
;
264 #define KLOGIN "/.k5login"
265 buflen
= strlen(profile_dir
) + sizeof(KLOGIN
) + 2; /* 2 for .d */
266 buf
= malloc(buflen
);
269 /* check user's ~/.k5login */
270 strlcpy(buf
, profile_dir
, buflen
);
271 strlcat(buf
, KLOGIN
, buflen
);
272 ret
= check_one_file(context
, buf
, pwd
, principal
, &result
);
274 if(ret
== 0 && result
== TRUE
) {
282 strlcat(buf
, ".d", buflen
);
283 ret
= check_directory(context
, buf
, pwd
, principal
, &result
);
285 if(ret
== 0 && result
== TRUE
)
288 if(ret
!= ENOENT
&& ret
!= ENOTDIR
)
291 /* finally if no files exist, allow all principals matching
292 <localuser>@<LOCALREALM> */
293 if(found_file
== FALSE
)
294 return match_local_principals(context
, principal
, luser
);
298 /* The .k5login file may be on a remote profile and we don't have
299 access to the profile until we have a token handle for the
300 user's credentials. */
301 return match_local_principals(context
, principal
, luser
);