kuserok.c revision 1.2 1 1.1 elric /* $NetBSD: kuserok.c,v 1.2 2017/01/28 21:31:49 christos Exp $ */
2 1.1 elric
3 1.1 elric /*
4 1.1 elric * Copyright (c) 1997 - 2005 Kungliga Tekniska Hgskolan
5 1.1 elric * (Royal Institute of Technology, Stockholm, Sweden).
6 1.1 elric * All rights reserved.
7 1.1 elric *
8 1.1 elric * Redistribution and use in source and binary forms, with or without
9 1.1 elric * modification, are permitted provided that the following conditions
10 1.1 elric * are met:
11 1.1 elric *
12 1.1 elric * 1. Redistributions of source code must retain the above copyright
13 1.1 elric * notice, this list of conditions and the following disclaimer.
14 1.1 elric *
15 1.1 elric * 2. Redistributions in binary form must reproduce the above copyright
16 1.1 elric * notice, this list of conditions and the following disclaimer in the
17 1.1 elric * documentation and/or other materials provided with the distribution.
18 1.1 elric *
19 1.1 elric * 3. Neither the name of the Institute nor the names of its contributors
20 1.1 elric * may be used to endorse or promote products derived from this software
21 1.1 elric * without specific prior written permission.
22 1.1 elric *
23 1.1 elric * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
24 1.1 elric * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 1.1 elric * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 1.1 elric * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
27 1.1 elric * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 1.1 elric * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 1.1 elric * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 1.1 elric * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 1.1 elric * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 1.1 elric * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 1.1 elric * SUCH DAMAGE.
34 1.1 elric */
35 1.1 elric
36 1.1 elric #include "krb5_locl.h"
37 1.2 christos #include "kuserok_plugin.h"
38 1.1 elric #include <dirent.h>
39 1.1 elric
40 1.2 christos #ifndef SYSTEM_K5LOGIN_DIR
41 1.2 christos /*
42 1.2 christos * System k5login location. File namess in this directory are expected
43 1.2 christos * to be usernames and to contain a list of principals allowed to login
44 1.2 christos * as the user named the same as the file.
45 1.2 christos */
46 1.2 christos #define SYSTEM_K5LOGIN_DIR SYSCONFDIR "/k5login.d"
47 1.2 christos #endif
48 1.2 christos
49 1.2 christos /* Plugin framework bits */
50 1.2 christos
51 1.2 christos struct plctx {
52 1.2 christos const char *rule;
53 1.2 christos const char *k5login_dir;
54 1.2 christos const char *luser;
55 1.2 christos krb5_const_principal principal;
56 1.2 christos unsigned int flags;
57 1.2 christos krb5_boolean result;
58 1.2 christos };
59 1.2 christos
60 1.2 christos static krb5_error_code KRB5_LIB_CALL
61 1.2 christos plcallback(krb5_context context, const void *plug, void *plugctx, void *userctx)
62 1.2 christos {
63 1.2 christos const krb5plugin_kuserok_ftable *locate = plug;
64 1.2 christos struct plctx *plctx = userctx;
65 1.2 christos
66 1.2 christos return locate->kuserok(plugctx, context, plctx->rule, plctx->flags,
67 1.2 christos plctx->k5login_dir, plctx->luser, plctx->principal,
68 1.2 christos &plctx->result);
69 1.2 christos }
70 1.2 christos
71 1.2 christos static krb5_error_code plugin_reg_ret;
72 1.2 christos static krb5plugin_kuserok_ftable kuserok_simple_plug;
73 1.2 christos static krb5plugin_kuserok_ftable kuserok_sys_k5login_plug;
74 1.2 christos static krb5plugin_kuserok_ftable kuserok_user_k5login_plug;
75 1.2 christos static krb5plugin_kuserok_ftable kuserok_deny_plug;
76 1.2 christos
77 1.2 christos static void
78 1.2 christos reg_def_plugins_once(void *ctx)
79 1.2 christos {
80 1.2 christos krb5_error_code ret;
81 1.2 christos krb5_context context = ctx;
82 1.2 christos
83 1.2 christos plugin_reg_ret = krb5_plugin_register(context, PLUGIN_TYPE_DATA,
84 1.2 christos KRB5_PLUGIN_KUSEROK,
85 1.2 christos &kuserok_simple_plug);
86 1.2 christos ret = krb5_plugin_register(context, PLUGIN_TYPE_DATA,
87 1.2 christos KRB5_PLUGIN_KUSEROK, &kuserok_sys_k5login_plug);
88 1.2 christos if (!plugin_reg_ret)
89 1.2 christos plugin_reg_ret = ret;
90 1.2 christos ret = krb5_plugin_register(context, PLUGIN_TYPE_DATA,
91 1.2 christos KRB5_PLUGIN_KUSEROK, &kuserok_user_k5login_plug);
92 1.2 christos if (!plugin_reg_ret)
93 1.2 christos plugin_reg_ret = ret;
94 1.2 christos ret = krb5_plugin_register(context, PLUGIN_TYPE_DATA,
95 1.2 christos KRB5_PLUGIN_KUSEROK, &kuserok_deny_plug);
96 1.2 christos if (!plugin_reg_ret)
97 1.2 christos plugin_reg_ret = ret;
98 1.2 christos }
99 1.2 christos
100 1.2 christos /**
101 1.2 christos * This function is designed to be portable for Win32 and POSIX. The
102 1.2 christos * design does lead to multiple getpwnam_r() calls, but this is probably
103 1.2 christos * not a big deal.
104 1.2 christos *
105 1.2 christos * Inputs:
106 1.2 christos *
107 1.2 christos * @param context A krb5_context
108 1.2 christos * @param filename Name of item to introspection
109 1.2 christos * @param is_system_location TRUE if the dir/file are system locations or
110 1.2 christos * FALSE if they are user home directory locations
111 1.2 christos * @param dir Directory (optional)
112 1.2 christos * @param dirlstat A pointer to struct stat for the directory (optional)
113 1.2 christos * @param file File (optional)
114 1.2 christos * @param owner Name of user that is expected to own the file
115 1.2 christos */
116 1.2 christos
117 1.2 christos static krb5_error_code
118 1.2 christos check_owner_dir(krb5_context context,
119 1.2 christos const char *filename,
120 1.2 christos krb5_boolean is_system_location,
121 1.2 christos DIR *dir,
122 1.2 christos struct stat *dirlstat,
123 1.2 christos const char *owner)
124 1.2 christos {
125 1.2 christos #ifdef _WIN32
126 1.2 christos /*
127 1.2 christos * XXX Implement this!
128 1.2 christos *
129 1.2 christos * The thing to do is to call _get_osfhandle() on fileno(file) and
130 1.2 christos * dirfd(dir) to get HANDLEs to the same, then call
131 1.2 christos * GetSecurityInfo() on those HANDLEs to get the security descriptor
132 1.2 christos * (SD), then check the owner and DACL. Checking the DACL sounds
133 1.2 christos * like a lot of work (what, derive a mode from the ACL the way
134 1.2 christos * NFSv4 servers do?). Checking the owner means doing an LSARPC
135 1.2 christos * lookup at least (to get the user's SID).
136 1.2 christos */
137 1.2 christos if (is_system_location || owner == NULL)
138 1.2 christos return 0;
139 1.2 christos krb5_set_error_message(context, EACCES,
140 1.2 christos "User k5login files not supported on Windows");
141 1.2 christos return EACCES;
142 1.2 christos #else
143 1.2 christos struct passwd pw, *pwd = NULL;
144 1.2 christos char pwbuf[2048];
145 1.2 christos struct stat st;
146 1.2 christos
147 1.2 christos heim_assert(owner != NULL, "no directory owner ?");
148 1.2 christos
149 1.2 christos if (rk_getpwnam_r(owner, &pw, pwbuf, sizeof(pwbuf), &pwd) != 0) {
150 1.2 christos krb5_set_error_message(context, errno,
151 1.2 christos "User unknown %s (getpwnam_r())", owner);
152 1.2 christos return EACCES;
153 1.2 christos }
154 1.2 christos if (pwd == NULL) {
155 1.2 christos krb5_set_error_message(context, EACCES, "no user %s", owner);
156 1.2 christos return EACCES;
157 1.2 christos }
158 1.2 christos
159 1.2 christos if (fstat(dirfd(dir), &st) == -1) {
160 1.2 christos krb5_set_error_message(context, EACCES,
161 1.2 christos "fstat(%s) of k5login.d failed",
162 1.2 christos filename);
163 1.2 christos return EACCES;
164 1.2 christos }
165 1.2 christos if (!S_ISDIR(st.st_mode)) {
166 1.2 christos krb5_set_error_message(context, ENOTDIR, "%s not a directory",
167 1.2 christos filename);
168 1.2 christos return ENOTDIR;
169 1.2 christos }
170 1.2 christos if (st.st_dev != dirlstat->st_dev || st.st_ino != dirlstat->st_ino) {
171 1.2 christos krb5_set_error_message(context, EACCES,
172 1.2 christos "%s was renamed during kuserok "
173 1.2 christos "operation", filename);
174 1.2 christos return EACCES;
175 1.2 christos }
176 1.2 christos if ((st.st_mode & (S_IWGRP | S_IWOTH)) != 0) {
177 1.2 christos krb5_set_error_message(context, EACCES,
178 1.2 christos "%s has world and/or group write "
179 1.2 christos "permissions", filename);
180 1.2 christos return EACCES;
181 1.2 christos }
182 1.2 christos if (pwd->pw_uid != st.st_uid && st.st_uid != 0) {
183 1.2 christos krb5_set_error_message(context, EACCES,
184 1.2 christos "%s not owned by the user (%s) or root",
185 1.2 christos filename, owner);
186 1.2 christos return EACCES;
187 1.2 christos }
188 1.2 christos
189 1.2 christos return 0;
190 1.2 christos #endif
191 1.2 christos }
192 1.2 christos
193 1.2 christos static krb5_error_code
194 1.2 christos check_owner_file(krb5_context context,
195 1.2 christos const char *filename,
196 1.2 christos FILE *file, const char *owner)
197 1.2 christos {
198 1.2 christos #ifdef _WIN32
199 1.2 christos /*
200 1.2 christos * XXX Implement this!
201 1.2 christos *
202 1.2 christos * The thing to do is to call _get_osfhandle() on fileno(file) and
203 1.2 christos * dirfd(dir) to get HANDLEs to the same, then call
204 1.2 christos * GetSecurityInfo() on those HANDLEs to get the security descriptor
205 1.2 christos * (SD), then check the owner and DACL. Checking the DACL sounds
206 1.2 christos * like a lot of work (what, derive a mode from the ACL the way
207 1.2 christos * NFSv4 servers do?). Checking the owner means doing an LSARPC
208 1.2 christos * lookup at least (to get the user's SID).
209 1.2 christos */
210 1.2 christos if (owner == NULL)
211 1.2 christos return 0;
212 1.2 christos
213 1.2 christos krb5_set_error_message(context, EACCES,
214 1.2 christos "User k5login files not supported on Windows");
215 1.2 christos return EACCES;
216 1.2 christos #else
217 1.2 christos struct passwd pw, *pwd = NULL;
218 1.2 christos char pwbuf[2048];
219 1.2 christos struct stat st;
220 1.2 christos
221 1.2 christos if (owner == NULL)
222 1.2 christos return 0;
223 1.2 christos
224 1.2 christos if (rk_getpwnam_r(owner, &pw, pwbuf, sizeof(pwbuf), &pwd) != 0) {
225 1.2 christos krb5_set_error_message(context, errno,
226 1.2 christos "User unknown %s (getpwnam_r())", owner);
227 1.2 christos return EACCES;
228 1.2 christos }
229 1.2 christos if (pwd == NULL) {
230 1.2 christos krb5_set_error_message(context, EACCES, "no user %s", owner);
231 1.2 christos return EACCES;
232 1.2 christos }
233 1.2 christos
234 1.2 christos if (fstat(fileno(file), &st) == -1) {
235 1.2 christos krb5_set_error_message(context, EACCES, "fstat(%s) of k5login failed",
236 1.2 christos filename);
237 1.2 christos return EACCES;
238 1.2 christos }
239 1.2 christos if (S_ISDIR(st.st_mode)) {
240 1.2 christos krb5_set_error_message(context, EISDIR, "k5login: %s is a directory",
241 1.2 christos filename);
242 1.2 christos return EISDIR;
243 1.2 christos }
244 1.2 christos if ((st.st_mode & (S_IWGRP | S_IWOTH)) != 0) {
245 1.2 christos krb5_set_error_message(context, EISDIR,
246 1.2 christos "k5login %s has world and/or group write "
247 1.2 christos "permissions", filename);
248 1.2 christos return EACCES;
249 1.2 christos }
250 1.2 christos if (pwd->pw_uid != st.st_uid && st.st_uid != 0) {
251 1.2 christos krb5_set_error_message(context, EACCES,
252 1.2 christos "k5login %s not owned by the user or root",
253 1.2 christos filename);
254 1.2 christos return EACCES;
255 1.2 christos }
256 1.2 christos
257 1.2 christos return 0;
258 1.2 christos #endif
259 1.2 christos }
260 1.2 christos
261 1.1 elric
262 1.1 elric /* see if principal is mentioned in the filename access file, return
263 1.1 elric TRUE (in result) if so, FALSE otherwise */
264 1.1 elric
265 1.1 elric static krb5_error_code
266 1.1 elric check_one_file(krb5_context context,
267 1.1 elric const char *filename,
268 1.2 christos const char *owner,
269 1.2 christos krb5_boolean is_system_location,
270 1.2 christos krb5_const_principal principal,
271 1.1 elric krb5_boolean *result)
272 1.1 elric {
273 1.1 elric FILE *f;
274 1.1 elric char buf[BUFSIZ];
275 1.1 elric krb5_error_code ret;
276 1.1 elric
277 1.1 elric *result = FALSE;
278 1.1 elric
279 1.2 christos f = fopen(filename, "r");
280 1.1 elric if (f == NULL)
281 1.1 elric return errno;
282 1.1 elric rk_cloexec_file(f);
283 1.1 elric
284 1.2 christos ret = check_owner_file(context, filename, f, owner);
285 1.2 christos if (ret)
286 1.2 christos goto out;
287 1.1 elric
288 1.2 christos while (fgets(buf, sizeof(buf), f) != NULL) {
289 1.1 elric krb5_principal tmp;
290 1.1 elric char *newline = buf + strcspn(buf, "\n");
291 1.1 elric
292 1.2 christos if (*newline != '\n') {
293 1.1 elric int c;
294 1.1 elric c = fgetc(f);
295 1.2 christos if (c != EOF) {
296 1.2 christos while (c != EOF && c != '\n')
297 1.1 elric c = fgetc(f);
298 1.1 elric /* line was too long, so ignore it */
299 1.1 elric continue;
300 1.1 elric }
301 1.1 elric }
302 1.1 elric *newline = '\0';
303 1.2 christos ret = krb5_parse_name(context, buf, &tmp);
304 1.1 elric if (ret)
305 1.1 elric continue;
306 1.2 christos *result = krb5_principal_compare(context, principal, tmp);
307 1.2 christos krb5_free_principal(context, tmp);
308 1.1 elric if (*result) {
309 1.1 elric fclose (f);
310 1.1 elric return 0;
311 1.1 elric }
312 1.1 elric }
313 1.2 christos
314 1.2 christos out:
315 1.2 christos fclose(f);
316 1.1 elric return 0;
317 1.1 elric }
318 1.1 elric
319 1.1 elric static krb5_error_code
320 1.1 elric check_directory(krb5_context context,
321 1.1 elric const char *dirname,
322 1.2 christos const char *owner,
323 1.2 christos krb5_boolean is_system_location,
324 1.2 christos krb5_const_principal principal,
325 1.1 elric krb5_boolean *result)
326 1.1 elric {
327 1.1 elric DIR *d;
328 1.1 elric struct dirent *dent;
329 1.1 elric char filename[MAXPATHLEN];
330 1.2 christos size_t len;
331 1.1 elric krb5_error_code ret = 0;
332 1.1 elric struct stat st;
333 1.1 elric
334 1.1 elric *result = FALSE;
335 1.1 elric
336 1.2 christos if (lstat(dirname, &st) < 0)
337 1.1 elric return errno;
338 1.1 elric
339 1.2 christos if (!S_ISDIR(st.st_mode)) {
340 1.2 christos krb5_set_error_message(context, ENOTDIR, "k5login.d not a directory");
341 1.1 elric return ENOTDIR;
342 1.2 christos }
343 1.1 elric
344 1.2 christos if ((d = opendir(dirname)) == NULL) {
345 1.2 christos krb5_set_error_message(context, ENOTDIR, "Could not open k5login.d");
346 1.1 elric return errno;
347 1.2 christos }
348 1.1 elric
349 1.2 christos ret = check_owner_dir(context, dirname, is_system_location, d, &st, owner);
350 1.2 christos if (ret)
351 1.2 christos goto out;
352 1.1 elric
353 1.2 christos while ((dent = readdir(d)) != NULL) {
354 1.2 christos /*
355 1.2 christos * XXX: Should we also skip files whose names start with "."?
356 1.2 christos * Vim ".filename.swp" files are also good candidates to skip.
357 1.2 christos * Once we ignore "#*" and "*~", it is not clear what other
358 1.2 christos * heuristics to apply.
359 1.2 christos */
360 1.2 christos if (strcmp(dent->d_name, ".") == 0 ||
361 1.1 elric strcmp(dent->d_name, "..") == 0 ||
362 1.1 elric dent->d_name[0] == '#' || /* emacs autosave */
363 1.1 elric dent->d_name[strlen(dent->d_name) - 1] == '~') /* emacs backup */
364 1.1 elric continue;
365 1.2 christos len = snprintf(filename, sizeof(filename), "%s/%s", dirname, dent->d_name);
366 1.2 christos /* Skip too-long filenames that got truncated by snprintf() */
367 1.2 christos if (len < sizeof(filename)) {
368 1.2 christos ret = check_one_file(context, filename, owner, is_system_location,
369 1.2 christos principal, result);
370 1.2 christos if (ret == 0 && *result == TRUE)
371 1.2 christos break;
372 1.2 christos }
373 1.1 elric ret = 0; /* don't propagate errors upstream */
374 1.1 elric }
375 1.2 christos
376 1.2 christos out:
377 1.1 elric closedir(d);
378 1.1 elric return ret;
379 1.1 elric }
380 1.1 elric
381 1.2 christos static krb5_error_code
382 1.2 christos check_an2ln(krb5_context context,
383 1.2 christos krb5_const_principal principal,
384 1.2 christos const char *luser,
385 1.2 christos krb5_boolean *result)
386 1.1 elric {
387 1.1 elric krb5_error_code ret;
388 1.2 christos char *lname;
389 1.1 elric
390 1.2 christos #if 0
391 1.2 christos /* XXX Should we make this an option? */
392 1.1 elric /* multi-component principals can never match */
393 1.2 christos if (krb5_principal_get_comp_string(context, principal, 1) != NULL) {
394 1.2 christos *result = FALSE;
395 1.2 christos return 0;
396 1.2 christos }
397 1.2 christos #endif
398 1.1 elric
399 1.2 christos lname = malloc(strlen(luser) + 1);
400 1.2 christos if (lname == NULL)
401 1.2 christos return krb5_enomem(context);
402 1.2 christos ret = krb5_aname_to_localname(context, principal, strlen(luser)+1, lname);
403 1.1 elric if (ret)
404 1.2 christos goto out;
405 1.2 christos if (strcmp(lname, luser) == 0)
406 1.2 christos *result = TRUE;
407 1.2 christos else
408 1.2 christos *result = FALSE;
409 1.2 christos
410 1.2 christos out:
411 1.2 christos free(lname);
412 1.2 christos return 0;
413 1.2 christos
414 1.1 elric }
415 1.1 elric
416 1.1 elric /**
417 1.1 elric * This function takes the name of a local user and checks if
418 1.1 elric * principal is allowed to log in as that user.
419 1.1 elric *
420 1.1 elric * The user may have a ~/.k5login file listing principals that are
421 1.1 elric * allowed to login as that user. If that file does not exist, all
422 1.2 christos * principals with a only one component that is identical to the
423 1.2 christos * username, and a realm considered local, are allowed access.
424 1.1 elric *
425 1.1 elric * The .k5login file must contain one principal per line, be owned by
426 1.1 elric * user and not be writable by group or other (but must be readable by
427 1.1 elric * anyone).
428 1.1 elric *
429 1.1 elric * Note that if the file exists, no implicit access rights are given
430 1.1 elric * to user@@LOCALREALM.
431 1.1 elric *
432 1.1 elric * Optionally, a set of files may be put in ~/.k5login.d (a
433 1.1 elric * directory), in which case they will all be checked in the same
434 1.1 elric * manner as .k5login. The files may be called anything, but files
435 1.1 elric * starting with a hash (#) , or ending with a tilde (~) are
436 1.1 elric * ignored. Subdirectories are not traversed. Note that this directory
437 1.1 elric * may not be checked by other Kerberos implementations.
438 1.1 elric *
439 1.1 elric * If no configuration file exists, match user against local domains,
440 1.1 elric * ie luser@@LOCAL-REALMS-IN-CONFIGURATION-FILES.
441 1.1 elric *
442 1.1 elric * @param context Kerberos 5 context.
443 1.1 elric * @param principal principal to check if allowed to login
444 1.1 elric * @param luser local user id
445 1.2 christos *
446 1.1 elric * @return returns TRUE if access should be granted, FALSE otherwise.
447 1.1 elric *
448 1.1 elric * @ingroup krb5_support
449 1.1 elric */
450 1.1 elric
451 1.1 elric KRB5_LIB_FUNCTION krb5_boolean KRB5_LIB_CALL
452 1.2 christos krb5_kuserok(krb5_context context,
453 1.2 christos krb5_principal principal,
454 1.2 christos const char *luser)
455 1.2 christos {
456 1.2 christos return _krb5_kuserok(context, principal, luser, TRUE);
457 1.2 christos }
458 1.2 christos
459 1.2 christos
460 1.2 christos KRB5_LIB_FUNCTION krb5_boolean KRB5_LIB_CALL
461 1.2 christos _krb5_kuserok(krb5_context context,
462 1.1 elric krb5_principal principal,
463 1.2 christos const char *luser,
464 1.2 christos krb5_boolean an2ln_ok)
465 1.2 christos {
466 1.2 christos static heim_base_once_t reg_def_plugins = HEIM_BASE_ONCE_INIT;
467 1.2 christos krb5_error_code ret;
468 1.2 christos struct plctx ctx;
469 1.2 christos char **rules;
470 1.2 christos
471 1.2 christos /*
472 1.2 christos * XXX we should have a struct with a krb5_context field and a
473 1.2 christos * krb5_error_code fied and pass the address of that as the ctx
474 1.2 christos * argument of heim_base_once_f(). For now we use a static to
475 1.2 christos * communicate failures. Actually, we ignore failures anyways,
476 1.2 christos * since we can't return them.
477 1.2 christos */
478 1.2 christos heim_base_once_f(®_def_plugins, context, reg_def_plugins_once);
479 1.2 christos
480 1.2 christos ctx.flags = 0;
481 1.2 christos ctx.luser = luser;
482 1.2 christos ctx.principal = principal;
483 1.2 christos ctx.result = FALSE;
484 1.2 christos
485 1.2 christos ctx.k5login_dir = krb5_config_get_string(context, NULL, "libdefaults",
486 1.2 christos "k5login_directory", NULL);
487 1.2 christos
488 1.2 christos if (an2ln_ok)
489 1.2 christos ctx.flags |= KUSEROK_ANAME_TO_LNAME_OK;
490 1.2 christos
491 1.2 christos if (krb5_config_get_bool_default(context, NULL, FALSE, "libdefaults",
492 1.2 christos "k5login_authoritative", NULL))
493 1.2 christos ctx.flags |= KUSEROK_K5LOGIN_IS_AUTHORITATIVE;
494 1.2 christos
495 1.2 christos if ((ctx.flags & KUSEROK_K5LOGIN_IS_AUTHORITATIVE) && plugin_reg_ret)
496 1.2 christos return plugin_reg_ret; /* fail safe */
497 1.2 christos
498 1.2 christos rules = krb5_config_get_strings(context, NULL, "libdefaults",
499 1.2 christos "kuserok", NULL);
500 1.2 christos if (rules == NULL) {
501 1.2 christos /* Default: check ~/.k5login */
502 1.2 christos ctx.rule = "USER-K5LOGIN";
503 1.2 christos
504 1.2 christos ret = plcallback(context, &kuserok_user_k5login_plug, NULL, &ctx);
505 1.2 christos if (ret == 0)
506 1.2 christos goto out;
507 1.2 christos
508 1.2 christos ctx.rule = "SIMPLE";
509 1.2 christos ret = plcallback(context, &kuserok_simple_plug, NULL, &ctx);
510 1.2 christos if (ret == 0)
511 1.2 christos goto out;
512 1.2 christos
513 1.2 christos ctx.result = FALSE;
514 1.2 christos } else {
515 1.2 christos size_t n;
516 1.2 christos
517 1.2 christos for (n = 0; rules[n]; n++) {
518 1.2 christos ctx.rule = rules[n];
519 1.2 christos
520 1.2 christos ret = _krb5_plugin_run_f(context, "krb5", KRB5_PLUGIN_KUSEROK,
521 1.2 christos KRB5_PLUGIN_KUSEROK_VERSION_0, 0,
522 1.2 christos &ctx, plcallback);
523 1.2 christos if (ret != KRB5_PLUGIN_NO_HANDLE)
524 1.2 christos goto out;
525 1.2 christos }
526 1.2 christos }
527 1.2 christos
528 1.2 christos out:
529 1.2 christos krb5_config_free_strings(rules);
530 1.2 christos
531 1.2 christos return ctx.result;
532 1.2 christos }
533 1.2 christos
534 1.2 christos /*
535 1.2 christos * Simple kuserok: check that the lname for the aname matches luser.
536 1.2 christos */
537 1.2 christos
538 1.2 christos static krb5_error_code KRB5_LIB_CALL
539 1.2 christos kuserok_simple_plug_f(void *plug_ctx, krb5_context context, const char *rule,
540 1.2 christos unsigned int flags, const char *k5login_dir,
541 1.2 christos const char *luser, krb5_const_principal principal,
542 1.2 christos krb5_boolean *result)
543 1.1 elric {
544 1.1 elric krb5_error_code ret;
545 1.1 elric
546 1.2 christos if (strcmp(rule, "SIMPLE") != 0 || (flags & KUSEROK_ANAME_TO_LNAME_OK) == 0)
547 1.2 christos return KRB5_PLUGIN_NO_HANDLE;
548 1.2 christos
549 1.2 christos ret = check_an2ln(context, principal, luser, result);
550 1.2 christos if (ret == 0 && *result == FALSE)
551 1.2 christos return KRB5_PLUGIN_NO_HANDLE;
552 1.2 christos
553 1.2 christos return 0;
554 1.2 christos }
555 1.2 christos
556 1.2 christos /*
557 1.2 christos * Check k5login files in a system location, rather than in home
558 1.2 christos * directories.
559 1.2 christos */
560 1.2 christos
561 1.2 christos static krb5_error_code KRB5_LIB_CALL
562 1.2 christos kuserok_sys_k5login_plug_f(void *plug_ctx, krb5_context context,
563 1.2 christos const char *rule, unsigned int flags,
564 1.2 christos const char *k5login_dir, const char *luser,
565 1.2 christos krb5_const_principal principal, krb5_boolean *result)
566 1.2 christos {
567 1.2 christos char filename[MAXPATHLEN];
568 1.2 christos size_t len;
569 1.2 christos const char *profile_dir = NULL;
570 1.2 christos krb5_error_code ret;
571 1.2 christos
572 1.2 christos *result = FALSE;
573 1.2 christos
574 1.2 christos if (strcmp(rule, "SYSTEM-K5LOGIN") != 0 &&
575 1.2 christos strncmp(rule, "SYSTEM-K5LOGIN:", strlen("SYSTEM-K5LOGIN:")) != 0)
576 1.2 christos return KRB5_PLUGIN_NO_HANDLE;
577 1.2 christos
578 1.2 christos profile_dir = strchr(rule, ':');
579 1.2 christos if (profile_dir == NULL)
580 1.2 christos profile_dir = k5login_dir ? k5login_dir : SYSTEM_K5LOGIN_DIR;
581 1.2 christos else
582 1.2 christos profile_dir++;
583 1.2 christos
584 1.2 christos len = snprintf(filename, sizeof(filename), "%s/%s", profile_dir, luser);
585 1.2 christos if (len < sizeof(filename)) {
586 1.2 christos ret = check_one_file(context, filename, NULL, TRUE, principal, result);
587 1.2 christos
588 1.2 christos if (ret == 0 &&
589 1.2 christos ((flags & KUSEROK_K5LOGIN_IS_AUTHORITATIVE) || *result == TRUE))
590 1.2 christos return 0;
591 1.2 christos }
592 1.2 christos
593 1.2 christos *result = FALSE;
594 1.2 christos return KRB5_PLUGIN_NO_HANDLE;
595 1.2 christos }
596 1.2 christos
597 1.2 christos /*
598 1.2 christos * Check ~luser/.k5login and/or ~/luser/.k5login.d
599 1.2 christos */
600 1.2 christos
601 1.2 christos static krb5_error_code KRB5_LIB_CALL
602 1.2 christos kuserok_user_k5login_plug_f(void *plug_ctx, krb5_context context,
603 1.2 christos const char *rule, unsigned int flags,
604 1.2 christos const char *k5login_dir, const char *luser,
605 1.2 christos krb5_const_principal principal,
606 1.2 christos krb5_boolean *result)
607 1.2 christos {
608 1.2 christos #ifdef _WIN32
609 1.2 christos return KRB5_PLUGIN_NO_HANDLE;
610 1.2 christos #else
611 1.2 christos char *path;
612 1.2 christos char *path_exp;
613 1.2 christos const char *profile_dir = NULL;
614 1.2 christos krb5_error_code ret;
615 1.1 elric krb5_boolean found_file = FALSE;
616 1.2 christos struct passwd pw, *pwd = NULL;
617 1.2 christos char pwbuf[2048];
618 1.1 elric
619 1.2 christos if (strcmp(rule, "USER-K5LOGIN") != 0)
620 1.2 christos return KRB5_PLUGIN_NO_HANDLE;
621 1.1 elric
622 1.2 christos profile_dir = k5login_dir;
623 1.2 christos if (profile_dir == NULL) {
624 1.2 christos /* Don't deadlock with gssd or anything of the sort */
625 1.2 christos if (!_krb5_homedir_access(context))
626 1.2 christos return KRB5_PLUGIN_NO_HANDLE;
627 1.2 christos
628 1.2 christos if (getpwnam_r(luser, &pw, pwbuf, sizeof(pwbuf), &pwd) != 0) {
629 1.2 christos krb5_set_error_message(context, errno, "User unknown (getpwnam_r())");
630 1.2 christos return KRB5_PLUGIN_NO_HANDLE;
631 1.2 christos }
632 1.2 christos if (pwd == NULL) {
633 1.2 christos krb5_set_error_message(context, errno, "User unknown (getpwnam())");
634 1.2 christos return KRB5_PLUGIN_NO_HANDLE;
635 1.2 christos }
636 1.2 christos profile_dir = pwd->pw_dir;
637 1.2 christos }
638 1.1 elric
639 1.1 elric #define KLOGIN "/.k5login"
640 1.2 christos
641 1.2 christos if (asprintf(&path, "%s/.k5login.d", profile_dir) == -1)
642 1.2 christos return krb5_enomem(context);
643 1.2 christos
644 1.2 christos ret = _krb5_expand_path_tokensv(context, path, 1, &path_exp,
645 1.2 christos "luser", luser, NULL);
646 1.2 christos free(path);
647 1.2 christos if (ret)
648 1.2 christos return ret;
649 1.2 christos path = path_exp;
650 1.2 christos
651 1.1 elric /* check user's ~/.k5login */
652 1.2 christos path[strlen(path) - strlen(".d")] = '\0';
653 1.2 christos ret = check_one_file(context, path, luser, FALSE, principal, result);
654 1.1 elric
655 1.2 christos /*
656 1.2 christos * A match in ~/.k5login is sufficient. A non-match, falls through to the
657 1.2 christos * .k5login.d code below.
658 1.2 christos */
659 1.2 christos if (ret == 0 && *result == TRUE) {
660 1.2 christos free(path);
661 1.2 christos return 0;
662 1.1 elric }
663 1.2 christos if (ret != ENOENT)
664 1.2 christos found_file = TRUE;
665 1.1 elric
666 1.2 christos /*
667 1.2 christos * A match in ~/.k5login.d/somefile is sufficient. A non-match, falls
668 1.2 christos * through to the code below that handles negative results.
669 1.2 christos *
670 1.2 christos * XXX: put back the .d; clever|hackish? you decide
671 1.2 christos */
672 1.2 christos path[strlen(path)] = '.';
673 1.2 christos ret = check_directory(context, path, luser, FALSE, principal, result);
674 1.2 christos free(path);
675 1.2 christos if (ret == 0 && *result == TRUE)
676 1.2 christos return 0;
677 1.2 christos if (ret != ENOENT && ret != ENOTDIR)
678 1.1 elric found_file = TRUE;
679 1.1 elric
680 1.2 christos /*
681 1.2 christos * When either ~/.k5login or ~/.k5login.d/ exists, but neither matches
682 1.2 christos * and we're authoritative, we're done. Otherwise, give other plugins
683 1.2 christos * a chance.
684 1.2 christos */
685 1.2 christos *result = FALSE;
686 1.2 christos if (found_file && (flags & KUSEROK_K5LOGIN_IS_AUTHORITATIVE))
687 1.2 christos return 0;
688 1.2 christos return KRB5_PLUGIN_NO_HANDLE;
689 1.2 christos #endif
690 1.2 christos }
691 1.1 elric
692 1.2 christos static krb5_error_code KRB5_LIB_CALL
693 1.2 christos kuserok_deny_plug_f(void *plug_ctx, krb5_context context, const char *rule,
694 1.2 christos unsigned int flags, const char *k5login_dir,
695 1.2 christos const char *luser, krb5_const_principal principal,
696 1.2 christos krb5_boolean *result)
697 1.2 christos {
698 1.2 christos if (strcmp(rule, "DENY") != 0)
699 1.2 christos return KRB5_PLUGIN_NO_HANDLE;
700 1.2 christos
701 1.2 christos *result = FALSE;
702 1.2 christos return 0;
703 1.2 christos }
704 1.1 elric
705 1.2 christos static krb5_error_code KRB5_LIB_CALL
706 1.2 christos kuser_ok_null_plugin_init(krb5_context context, void **ctx)
707 1.2 christos {
708 1.2 christos *ctx = NULL;
709 1.2 christos return 0;
710 1.2 christos }
711 1.1 elric
712 1.2 christos static void KRB5_LIB_CALL
713 1.2 christos kuser_ok_null_plugin_fini(void *ctx)
714 1.2 christos {
715 1.2 christos return;
716 1.1 elric }
717 1.2 christos
718 1.2 christos static krb5plugin_kuserok_ftable kuserok_simple_plug = {
719 1.2 christos KRB5_PLUGIN_KUSEROK_VERSION_0,
720 1.2 christos kuser_ok_null_plugin_init,
721 1.2 christos kuser_ok_null_plugin_fini,
722 1.2 christos kuserok_simple_plug_f,
723 1.2 christos };
724 1.2 christos
725 1.2 christos static krb5plugin_kuserok_ftable kuserok_sys_k5login_plug = {
726 1.2 christos KRB5_PLUGIN_KUSEROK_VERSION_0,
727 1.2 christos kuser_ok_null_plugin_init,
728 1.2 christos kuser_ok_null_plugin_fini,
729 1.2 christos kuserok_sys_k5login_plug_f,
730 1.2 christos };
731 1.2 christos
732 1.2 christos static krb5plugin_kuserok_ftable kuserok_user_k5login_plug = {
733 1.2 christos KRB5_PLUGIN_KUSEROK_VERSION_0,
734 1.2 christos kuser_ok_null_plugin_init,
735 1.2 christos kuser_ok_null_plugin_fini,
736 1.2 christos kuserok_user_k5login_plug_f,
737 1.2 christos };
738 1.2 christos
739 1.2 christos static krb5plugin_kuserok_ftable kuserok_deny_plug = {
740 1.2 christos KRB5_PLUGIN_KUSEROK_VERSION_0,
741 1.2 christos kuser_ok_null_plugin_init,
742 1.2 christos kuser_ok_null_plugin_fini,
743 1.2 christos kuserok_deny_plug_f,
744 1.2 christos };
745 1.2 christos
746