xref: /minix3/crypto/external/bsd/heimdal/dist/lib/krb5/keytab.c (revision 0a6a1f1d05b60e214de2f05a7310ddd1f0e590e7)
1 /*	$NetBSD: keytab.c,v 1.1.1.2 2014/04/24 12:45:50 pettai Exp $	*/
2 
3 /*
4  * Copyright (c) 1997 - 2005 Kungliga Tekniska Högskolan
5  * (Royal Institute of Technology, Stockholm, Sweden).
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * 3. Neither the name of the Institute nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include "krb5_locl.h"
37 
38 /**
39  * @page krb5_keytab_intro The keytab handing functions
40  * @section section_krb5_keytab Kerberos Keytabs
41  *
42  * See the library functions here: @ref krb5_keytab
43  *
44  * Keytabs are long term key storage for servers, their equvalment of
45  * password files.
46  *
47  * Normally the only function that useful for server are to specify
48  * what keytab to use to other core functions like krb5_rd_req()
49  * krb5_kt_resolve(), and krb5_kt_close().
50  *
51  * @subsection krb5_keytab_names Keytab names
52  *
53  * A keytab name is on the form type:residual. The residual part is
54  * specific to each keytab-type.
55  *
56  * When a keytab-name is resolved, the type is matched with an internal
57  * list of keytab types. If there is no matching keytab type,
58  * the default keytab is used. The current default type is FILE.
59  *
60  * The default value can be changed in the configuration file
61  * /etc/krb5.conf by setting the variable
62  * [defaults]default_keytab_name.
63  *
64  * The keytab types that are implemented in Heimdal are:
65  * - file
66  *   store the keytab in a file, the type's name is FILE .  The
67  *   residual part is a filename. For compatibility with other
68  *   Kerberos implemtation WRFILE and JAVA14 is also accepted.  WRFILE
69  *   has the same format as FILE. JAVA14 have a format that is
70  *   compatible with older versions of MIT kerberos and SUN's Java
71  *   based installation.  They store a truncted kvno, so when the knvo
72  *   excess 255, they are truncted in this format.
73  *
74  * - keytab
75  *   store the keytab in a AFS keyfile (usually /usr/afs/etc/KeyFile ),
76  *   the type's name is AFSKEYFILE. The residual part is a filename.
77  *
78  * - memory
79  *   The keytab is stored in a memory segment. This allows sensitive
80  *   and/or temporary data not to be stored on disk. The type's name
81  *   is MEMORY. Each MEMORY keytab is referenced counted by and
82  *   opened by the residual name, so two handles can point to the
83  *   same memory area.  When the last user closes using krb5_kt_close()
84  *   the keytab, the keys in they keytab is memset() to zero and freed
85  *   and can no longer be looked up by name.
86  *
87  *
88  * @subsection krb5_keytab_example Keytab example
89  *
90  *  This is a minimalistic version of ktutil.
91  *
92  * @code
93 int
94 main (int argc, char **argv)
95 {
96     krb5_context context;
97     krb5_keytab keytab;
98     krb5_kt_cursor cursor;
99     krb5_keytab_entry entry;
100     krb5_error_code ret;
101     char *principal;
102 
103     if (krb5_init_context (&context) != 0)
104 	errx(1, "krb5_context");
105 
106     ret = krb5_kt_default (context, &keytab);
107     if (ret)
108 	krb5_err(context, 1, ret, "krb5_kt_default");
109 
110     ret = krb5_kt_start_seq_get(context, keytab, &cursor);
111     if (ret)
112 	krb5_err(context, 1, ret, "krb5_kt_start_seq_get");
113     while((ret = krb5_kt_next_entry(context, keytab, &entry, &cursor)) == 0){
114 	krb5_unparse_name(context, entry.principal, &principal);
115 	printf("principal: %s\n", principal);
116 	free(principal);
117 	krb5_kt_free_entry(context, &entry);
118     }
119     ret = krb5_kt_end_seq_get(context, keytab, &cursor);
120     if (ret)
121 	krb5_err(context, 1, ret, "krb5_kt_end_seq_get");
122     ret = krb5_kt_close(context, keytab);
123     if (ret)
124 	krb5_err(context, 1, ret, "krb5_kt_close");
125     krb5_free_context(context);
126     return 0;
127 }
128  * @endcode
129  *
130  */
131 
132 
133 /**
134  * Register a new keytab backend.
135  *
136  * @param context a Keberos context.
137  * @param ops a backend to register.
138  *
139  * @return Return an error code or 0, see krb5_get_error_message().
140  *
141  * @ingroup krb5_keytab
142  */
143 
144 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_kt_register(krb5_context context,const krb5_kt_ops * ops)145 krb5_kt_register(krb5_context context,
146 		 const krb5_kt_ops *ops)
147 {
148     struct krb5_keytab_data *tmp;
149 
150     if (strlen(ops->prefix) > KRB5_KT_PREFIX_MAX_LEN - 1) {
151 	krb5_set_error_message(context, KRB5_KT_BADNAME,
152 			       N_("can't register cache type, prefix too long", ""));
153 	return KRB5_KT_BADNAME;
154     }
155 
156     tmp = realloc(context->kt_types,
157 		  (context->num_kt_types + 1) * sizeof(*context->kt_types));
158     if(tmp == NULL) {
159 	krb5_set_error_message(context, ENOMEM,
160 			       N_("malloc: out of memory", ""));
161 	return ENOMEM;
162     }
163     memcpy(&tmp[context->num_kt_types], ops,
164 	   sizeof(tmp[context->num_kt_types]));
165     context->kt_types = tmp;
166     context->num_kt_types++;
167     return 0;
168 }
169 
170 static const char *
keytab_name(const char * name,const char ** type,size_t * type_len)171 keytab_name(const char *name, const char **type, size_t *type_len)
172 {
173     const char *residual;
174 
175     residual = strchr(name, ':');
176 
177     if (residual == NULL ||
178 	name[0] == '/'
179 #ifdef _WIN32
180         /* Avoid treating <drive>:<path> as a keytab type
181          * specification */
182         || name + 1 == residual
183 #endif
184         ) {
185 
186         *type = "FILE";
187         *type_len = strlen(*type);
188         residual = name;
189     } else {
190         *type = name;
191         *type_len = residual - name;
192         residual++;
193     }
194 
195     return residual;
196 }
197 
198 /**
199  * Resolve the keytab name (of the form `type:residual') in `name'
200  * into a keytab in `id'.
201  *
202  * @param context a Keberos context.
203  * @param name name to resolve
204  * @param id resulting keytab, free with krb5_kt_close().
205  *
206  * @return Return an error code or 0, see krb5_get_error_message().
207  *
208  * @ingroup krb5_keytab
209  */
210 
211 
212 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_kt_resolve(krb5_context context,const char * name,krb5_keytab * id)213 krb5_kt_resolve(krb5_context context,
214 		const char *name,
215 		krb5_keytab *id)
216 {
217     krb5_keytab k;
218     int i;
219     const char *type, *residual;
220     size_t type_len;
221     krb5_error_code ret;
222 
223     residual = keytab_name(name, &type, &type_len);
224 
225     for(i = 0; i < context->num_kt_types; i++) {
226 	if(strncasecmp(type, context->kt_types[i].prefix, type_len) == 0)
227 	    break;
228     }
229     if(i == context->num_kt_types) {
230 	krb5_set_error_message(context, KRB5_KT_UNKNOWN_TYPE,
231 			       N_("unknown keytab type %.*s", "type"),
232 			       (int)type_len, type);
233 	return KRB5_KT_UNKNOWN_TYPE;
234     }
235 
236     k = malloc (sizeof(*k));
237     if (k == NULL) {
238 	krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
239 	return ENOMEM;
240     }
241     memcpy(k, &context->kt_types[i], sizeof(*k));
242     k->data = NULL;
243     ret = (*k->resolve)(context, residual, k);
244     if(ret) {
245 	free(k);
246 	k = NULL;
247     }
248     *id = k;
249     return ret;
250 }
251 
252 /**
253  * copy the name of the default keytab into `name'.
254  *
255  * @param context a Keberos context.
256  * @param name buffer where the name will be written
257  * @param namesize length of name
258  *
259  * @return Return an error code or 0, see krb5_get_error_message().
260  *
261  * @ingroup krb5_keytab
262  */
263 
264 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_kt_default_name(krb5_context context,char * name,size_t namesize)265 krb5_kt_default_name(krb5_context context, char *name, size_t namesize)
266 {
267     if (strlcpy (name, context->default_keytab, namesize) >= namesize) {
268 	krb5_clear_error_message (context);
269 	return KRB5_CONFIG_NOTENUFSPACE;
270     }
271     return 0;
272 }
273 
274 /**
275  * Copy the name of the default modify keytab into `name'.
276  *
277  * @param context a Keberos context.
278  * @param name buffer where the name will be written
279  * @param namesize length of name
280  *
281  * @return Return an error code or 0, see krb5_get_error_message().
282  *
283  * @ingroup krb5_keytab
284  */
285 
286 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_kt_default_modify_name(krb5_context context,char * name,size_t namesize)287 krb5_kt_default_modify_name(krb5_context context, char *name, size_t namesize)
288 {
289     const char *kt = NULL;
290     if(context->default_keytab_modify == NULL) {
291 	if(strncasecmp(context->default_keytab, "ANY:", 4) != 0)
292 	    kt = context->default_keytab;
293 	else {
294 	    size_t len = strcspn(context->default_keytab + 4, ",");
295 	    if(len >= namesize) {
296 		krb5_clear_error_message(context);
297 		return KRB5_CONFIG_NOTENUFSPACE;
298 	    }
299 	    strlcpy(name, context->default_keytab + 4, namesize);
300 	    name[len] = '\0';
301 	    return 0;
302 	}
303     } else
304 	kt = context->default_keytab_modify;
305     if (strlcpy (name, kt, namesize) >= namesize) {
306 	krb5_clear_error_message (context);
307 	return KRB5_CONFIG_NOTENUFSPACE;
308     }
309     return 0;
310 }
311 
312 /**
313  * Set `id' to the default keytab.
314  *
315  * @param context a Keberos context.
316  * @param id the new default keytab.
317  *
318  * @return Return an error code or 0, see krb5_get_error_message().
319  *
320  * @ingroup krb5_keytab
321  */
322 
323 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_kt_default(krb5_context context,krb5_keytab * id)324 krb5_kt_default(krb5_context context, krb5_keytab *id)
325 {
326     return krb5_kt_resolve (context, context->default_keytab, id);
327 }
328 
329 /**
330  * Read the key identified by `(principal, vno, enctype)' from the
331  * keytab in `keyprocarg' (the default if == NULL) into `*key'.
332  *
333  * @param context a Keberos context.
334  * @param keyprocarg
335  * @param principal
336  * @param vno
337  * @param enctype
338  * @param key
339  *
340  * @return Return an error code or 0, see krb5_get_error_message().
341  *
342  * @ingroup krb5_keytab
343  */
344 
345 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_kt_read_service_key(krb5_context context,krb5_pointer keyprocarg,krb5_principal principal,krb5_kvno vno,krb5_enctype enctype,krb5_keyblock ** key)346 krb5_kt_read_service_key(krb5_context context,
347 			 krb5_pointer keyprocarg,
348 			 krb5_principal principal,
349 			 krb5_kvno vno,
350 			 krb5_enctype enctype,
351 			 krb5_keyblock **key)
352 {
353     krb5_keytab keytab;
354     krb5_keytab_entry entry;
355     krb5_error_code ret;
356 
357     if (keyprocarg)
358 	ret = krb5_kt_resolve (context, keyprocarg, &keytab);
359     else
360 	ret = krb5_kt_default (context, &keytab);
361 
362     if (ret)
363 	return ret;
364 
365     ret = krb5_kt_get_entry (context, keytab, principal, vno, enctype, &entry);
366     krb5_kt_close (context, keytab);
367     if (ret)
368 	return ret;
369     ret = krb5_copy_keyblock (context, &entry.keyblock, key);
370     krb5_kt_free_entry(context, &entry);
371     return ret;
372 }
373 
374 /**
375  * Return the type of the `keytab' in the string `prefix of length
376  * `prefixsize'.
377  *
378  * @param context a Keberos context.
379  * @param keytab the keytab to get the prefix for
380  * @param prefix prefix buffer
381  * @param prefixsize length of prefix buffer
382  *
383  * @return Return an error code or 0, see krb5_get_error_message().
384  *
385  * @ingroup krb5_keytab
386  */
387 
388 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_kt_get_type(krb5_context context,krb5_keytab keytab,char * prefix,size_t prefixsize)389 krb5_kt_get_type(krb5_context context,
390 		 krb5_keytab keytab,
391 		 char *prefix,
392 		 size_t prefixsize)
393 {
394     strlcpy(prefix, keytab->prefix, prefixsize);
395     return 0;
396 }
397 
398 /**
399  * Retrieve the name of the keytab `keytab' into `name', `namesize'
400  *
401  * @param context a Keberos context.
402  * @param keytab the keytab to get the name for.
403  * @param name name buffer.
404  * @param namesize size of name buffer.
405  *
406  * @return Return an error code or 0, see krb5_get_error_message().
407  *
408  * @ingroup krb5_keytab
409  */
410 
411 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_kt_get_name(krb5_context context,krb5_keytab keytab,char * name,size_t namesize)412 krb5_kt_get_name(krb5_context context,
413 		 krb5_keytab keytab,
414 		 char *name,
415 		 size_t namesize)
416 {
417     return (*keytab->get_name)(context, keytab, name, namesize);
418 }
419 
420 /**
421  * Retrieve the full name of the keytab `keytab' and store the name in
422  * `str'.
423  *
424  * @param context a Keberos context.
425  * @param keytab keytab to get name for.
426  * @param str the name of the keytab name, usee krb5_xfree() to free
427  *        the string.  On error, *str is set to NULL.
428  *
429  * @return Return an error code or 0, see krb5_get_error_message().
430  *
431  * @ingroup krb5_keytab
432  */
433 
434 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_kt_get_full_name(krb5_context context,krb5_keytab keytab,char ** str)435 krb5_kt_get_full_name(krb5_context context,
436 		      krb5_keytab keytab,
437 		      char **str)
438 {
439     char type[KRB5_KT_PREFIX_MAX_LEN];
440     char name[MAXPATHLEN];
441     krb5_error_code ret;
442 
443     *str = NULL;
444 
445     ret = krb5_kt_get_type(context, keytab, type, sizeof(type));
446     if (ret)
447 	return ret;
448 
449     ret = krb5_kt_get_name(context, keytab, name, sizeof(name));
450     if (ret)
451 	return ret;
452 
453     if (asprintf(str, "%s:%s", type, name) == -1) {
454 	krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
455 	*str = NULL;
456 	return ENOMEM;
457     }
458 
459     return 0;
460 }
461 
462 /**
463  * Finish using the keytab in `id'.  All resources will be released,
464  * even on errors.
465  *
466  * @param context a Keberos context.
467  * @param id keytab to close.
468  *
469  * @return Return an error code or 0, see krb5_get_error_message().
470  *
471  * @ingroup krb5_keytab
472  */
473 
474 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_kt_close(krb5_context context,krb5_keytab id)475 krb5_kt_close(krb5_context context,
476 	      krb5_keytab id)
477 {
478     krb5_error_code ret;
479 
480     ret = (*id->close)(context, id);
481     memset(id, 0, sizeof(*id));
482     free(id);
483     return ret;
484 }
485 
486 /**
487  * Destroy (remove) the keytab in `id'.  All resources will be released,
488  * even on errors, does the equvalment of krb5_kt_close() on the resources.
489  *
490  * @param context a Keberos context.
491  * @param id keytab to destroy.
492  *
493  * @return Return an error code or 0, see krb5_get_error_message().
494  *
495  * @ingroup krb5_keytab
496  */
497 
498 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_kt_destroy(krb5_context context,krb5_keytab id)499 krb5_kt_destroy(krb5_context context,
500 		krb5_keytab id)
501 {
502     krb5_error_code ret;
503 
504     ret = (*id->destroy)(context, id);
505     krb5_kt_close(context, id);
506     return ret;
507 }
508 
509 /*
510  * Match any aliases in keytab `entry' with `principal'.
511  */
512 
513 static krb5_boolean
compare_aliseses(krb5_context context,krb5_keytab_entry * entry,krb5_const_principal principal)514 compare_aliseses(krb5_context context,
515 		 krb5_keytab_entry *entry,
516 		 krb5_const_principal principal)
517 {
518     unsigned int i;
519     if (entry->aliases == NULL)
520 	return FALSE;
521     for (i = 0; i < entry->aliases->len; i++)
522 	if (krb5_principal_compare(context, &entry->aliases->val[i], principal))
523 	    return TRUE;
524     return FALSE;
525 }
526 
527 /**
528  * Compare `entry' against `principal, vno, enctype'.
529  * Any of `principal, vno, enctype' might be 0 which acts as a wildcard.
530  * Return TRUE if they compare the same, FALSE otherwise.
531  *
532  * @param context a Keberos context.
533  * @param entry an entry to match with.
534  * @param principal principal to match, NULL matches all principals.
535  * @param vno key version to match, 0 matches all key version numbers.
536  * @param enctype encryption type to match, 0 matches all encryption types.
537  *
538  * @return Return TRUE or match, FALSE if not matched.
539  *
540  * @ingroup krb5_keytab
541  */
542 
543 KRB5_LIB_FUNCTION krb5_boolean KRB5_LIB_CALL
krb5_kt_compare(krb5_context context,krb5_keytab_entry * entry,krb5_const_principal principal,krb5_kvno vno,krb5_enctype enctype)544 krb5_kt_compare(krb5_context context,
545 		krb5_keytab_entry *entry,
546 		krb5_const_principal principal,
547 		krb5_kvno vno,
548 		krb5_enctype enctype)
549 {
550     if(principal != NULL &&
551        !(krb5_principal_compare(context, entry->principal, principal) ||
552 	 compare_aliseses(context, entry, principal)))
553 	return FALSE;
554     if(vno && vno != entry->vno)
555 	return FALSE;
556     if(enctype && enctype != entry->keyblock.keytype)
557 	return FALSE;
558     return TRUE;
559 }
560 
561 krb5_error_code
_krb5_kt_principal_not_found(krb5_context context,krb5_error_code ret,krb5_keytab id,krb5_const_principal principal,krb5_enctype enctype,int kvno)562 _krb5_kt_principal_not_found(krb5_context context,
563 			     krb5_error_code ret,
564 			     krb5_keytab id,
565 			     krb5_const_principal principal,
566 			     krb5_enctype enctype,
567 			     int kvno)
568 {
569     char princ[256], kvno_str[25], *kt_name;
570     char *enctype_str = NULL;
571 
572     krb5_unparse_name_fixed (context, principal, princ, sizeof(princ));
573     krb5_kt_get_full_name (context, id, &kt_name);
574     krb5_enctype_to_string(context, enctype, &enctype_str);
575 
576     if (kvno)
577 	snprintf(kvno_str, sizeof(kvno_str), "(kvno %d)", kvno);
578     else
579 	kvno_str[0] = '\0';
580 
581     krb5_set_error_message (context, ret,
582 			    N_("Failed to find %s%s in keytab %s (%s)",
583 			       "principal, kvno, keytab file, enctype"),
584 			    princ,
585 			    kvno_str,
586 			    kt_name ? kt_name : "unknown keytab",
587 			    enctype_str ? enctype_str : "unknown enctype");
588     free(kt_name);
589     free(enctype_str);
590     return ret;
591 }
592 
593 
594 /**
595  * Retrieve the keytab entry for `principal, kvno, enctype' into `entry'
596  * from the keytab `id'. Matching is done like krb5_kt_compare().
597  *
598  * @param context a Keberos context.
599  * @param id a keytab.
600  * @param principal principal to match, NULL matches all principals.
601  * @param kvno key version to match, 0 matches all key version numbers.
602  * @param enctype encryption type to match, 0 matches all encryption types.
603  * @param entry the returned entry, free with krb5_kt_free_entry().
604  *
605  * @return Return an error code or 0, see krb5_get_error_message().
606  *
607  * @ingroup krb5_keytab
608  */
609 
610 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_kt_get_entry(krb5_context context,krb5_keytab id,krb5_const_principal principal,krb5_kvno kvno,krb5_enctype enctype,krb5_keytab_entry * entry)611 krb5_kt_get_entry(krb5_context context,
612 		  krb5_keytab id,
613 		  krb5_const_principal principal,
614 		  krb5_kvno kvno,
615 		  krb5_enctype enctype,
616 		  krb5_keytab_entry *entry)
617 {
618     krb5_keytab_entry tmp;
619     krb5_error_code ret;
620     krb5_kt_cursor cursor;
621 
622     if(id->get)
623 	return (*id->get)(context, id, principal, kvno, enctype, entry);
624 
625     ret = krb5_kt_start_seq_get (context, id, &cursor);
626     if (ret) {
627 	/* This is needed for krb5_verify_init_creds, but keep error
628 	 * string from previous error for the human. */
629 	context->error_code = KRB5_KT_NOTFOUND;
630 	return KRB5_KT_NOTFOUND;
631     }
632 
633     entry->vno = 0;
634     while (krb5_kt_next_entry(context, id, &tmp, &cursor) == 0) {
635 	if (krb5_kt_compare(context, &tmp, principal, 0, enctype)) {
636 	    /* the file keytab might only store the lower 8 bits of
637 	       the kvno, so only compare those bits */
638 	    if (kvno == tmp.vno
639 		|| (tmp.vno < 256 && kvno % 256 == tmp.vno)) {
640 		krb5_kt_copy_entry_contents (context, &tmp, entry);
641 		krb5_kt_free_entry (context, &tmp);
642 		krb5_kt_end_seq_get(context, id, &cursor);
643 		return 0;
644 	    } else if (kvno == 0 && tmp.vno > entry->vno) {
645 		if (entry->vno)
646 		    krb5_kt_free_entry (context, entry);
647 		krb5_kt_copy_entry_contents (context, &tmp, entry);
648 	    }
649 	}
650 	krb5_kt_free_entry(context, &tmp);
651     }
652     krb5_kt_end_seq_get (context, id, &cursor);
653     if (entry->vno == 0)
654 	return _krb5_kt_principal_not_found(context, KRB5_KT_NOTFOUND,
655 					    id, principal, enctype, kvno);
656     return 0;
657 }
658 
659 /**
660  * Copy the contents of `in' into `out'.
661  *
662  * @param context a Keberos context.
663  * @param in the keytab entry to copy.
664  * @param out the copy of the keytab entry, free with krb5_kt_free_entry().
665  *
666  * @return Return an error code or 0, see krb5_get_error_message().
667  *
668  * @ingroup krb5_keytab
669  */
670 
671 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_kt_copy_entry_contents(krb5_context context,const krb5_keytab_entry * in,krb5_keytab_entry * out)672 krb5_kt_copy_entry_contents(krb5_context context,
673 			    const krb5_keytab_entry *in,
674 			    krb5_keytab_entry *out)
675 {
676     krb5_error_code ret;
677 
678     memset(out, 0, sizeof(*out));
679     out->vno = in->vno;
680 
681     ret = krb5_copy_principal (context, in->principal, &out->principal);
682     if (ret)
683 	goto fail;
684     ret = krb5_copy_keyblock_contents (context,
685 				       &in->keyblock,
686 				       &out->keyblock);
687     if (ret)
688 	goto fail;
689     out->timestamp = in->timestamp;
690     return 0;
691 fail:
692     krb5_kt_free_entry (context, out);
693     return ret;
694 }
695 
696 /**
697  * Free the contents of `entry'.
698  *
699  * @param context a Keberos context.
700  * @param entry the entry to free
701  *
702  * @return Return an error code or 0, see krb5_get_error_message().
703  *
704  * @ingroup krb5_keytab
705  */
706 
707 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_kt_free_entry(krb5_context context,krb5_keytab_entry * entry)708 krb5_kt_free_entry(krb5_context context,
709 		   krb5_keytab_entry *entry)
710 {
711     krb5_free_principal (context, entry->principal);
712     krb5_free_keyblock_contents (context, &entry->keyblock);
713     memset(entry, 0, sizeof(*entry));
714     return 0;
715 }
716 
717 /**
718  * Set `cursor' to point at the beginning of `id'.
719  *
720  * @param context a Keberos context.
721  * @param id a keytab.
722  * @param cursor a newly allocated cursor, free with krb5_kt_end_seq_get().
723  *
724  * @return Return an error code or 0, see krb5_get_error_message().
725  *
726  * @ingroup krb5_keytab
727  */
728 
729 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_kt_start_seq_get(krb5_context context,krb5_keytab id,krb5_kt_cursor * cursor)730 krb5_kt_start_seq_get(krb5_context context,
731 		      krb5_keytab id,
732 		      krb5_kt_cursor *cursor)
733 {
734     if(id->start_seq_get == NULL) {
735 	krb5_set_error_message(context, HEIM_ERR_OPNOTSUPP,
736 			       N_("start_seq_get is not supported "
737 				  "in the %s keytab type", ""),
738 			       id->prefix);
739 	return HEIM_ERR_OPNOTSUPP;
740     }
741     return (*id->start_seq_get)(context, id, cursor);
742 }
743 
744 /**
745  * Get the next entry from keytab, advance the cursor.  On last entry
746  * the function will return KRB5_KT_END.
747  *
748  * @param context a Keberos context.
749  * @param id a keytab.
750  * @param entry the returned entry, free with krb5_kt_free_entry().
751  * @param cursor the cursor of the iteration.
752  *
753  * @return Return an error code or 0, see krb5_get_error_message().
754  *
755  * @ingroup krb5_keytab
756  */
757 
758 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_kt_next_entry(krb5_context context,krb5_keytab id,krb5_keytab_entry * entry,krb5_kt_cursor * cursor)759 krb5_kt_next_entry(krb5_context context,
760 		   krb5_keytab id,
761 		   krb5_keytab_entry *entry,
762 		   krb5_kt_cursor *cursor)
763 {
764     if(id->next_entry == NULL) {
765 	krb5_set_error_message(context, HEIM_ERR_OPNOTSUPP,
766 			       N_("next_entry is not supported in the %s "
767 				  " keytab", ""),
768 			       id->prefix);
769 	return HEIM_ERR_OPNOTSUPP;
770     }
771     return (*id->next_entry)(context, id, entry, cursor);
772 }
773 
774 /**
775  * Release all resources associated with `cursor'.
776  *
777  * @param context a Keberos context.
778  * @param id a keytab.
779  * @param cursor the cursor to free.
780  *
781  * @return Return an error code or 0, see krb5_get_error_message().
782  *
783  * @ingroup krb5_keytab
784  */
785 
786 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_kt_end_seq_get(krb5_context context,krb5_keytab id,krb5_kt_cursor * cursor)787 krb5_kt_end_seq_get(krb5_context context,
788 		    krb5_keytab id,
789 		    krb5_kt_cursor *cursor)
790 {
791     if(id->end_seq_get == NULL) {
792 	krb5_set_error_message(context, HEIM_ERR_OPNOTSUPP,
793 			       "end_seq_get is not supported in the %s "
794 			       " keytab", id->prefix);
795 	return HEIM_ERR_OPNOTSUPP;
796     }
797     return (*id->end_seq_get)(context, id, cursor);
798 }
799 
800 /**
801  * Add the entry in `entry' to the keytab `id'.
802  *
803  * @param context a Keberos context.
804  * @param id a keytab.
805  * @param entry the entry to add
806  *
807  * @return Return an error code or 0, see krb5_get_error_message().
808  *
809  * @ingroup krb5_keytab
810  */
811 
812 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_kt_add_entry(krb5_context context,krb5_keytab id,krb5_keytab_entry * entry)813 krb5_kt_add_entry(krb5_context context,
814 		  krb5_keytab id,
815 		  krb5_keytab_entry *entry)
816 {
817     if(id->add == NULL) {
818 	krb5_set_error_message(context, KRB5_KT_NOWRITE,
819 			       N_("Add is not supported in the %s keytab", ""),
820 			       id->prefix);
821 	return KRB5_KT_NOWRITE;
822     }
823     entry->timestamp = time(NULL);
824     return (*id->add)(context, id,entry);
825 }
826 
827 /**
828  * Remove an entry from the keytab, matching is done using
829  * krb5_kt_compare().
830 
831  * @param context a Keberos context.
832  * @param id a keytab.
833  * @param entry the entry to remove
834  *
835  * @return Return an error code or 0, see krb5_get_error_message().
836  *
837  * @ingroup krb5_keytab
838  */
839 
840 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_kt_remove_entry(krb5_context context,krb5_keytab id,krb5_keytab_entry * entry)841 krb5_kt_remove_entry(krb5_context context,
842 		     krb5_keytab id,
843 		     krb5_keytab_entry *entry)
844 {
845     if(id->remove == NULL) {
846 	krb5_set_error_message(context, KRB5_KT_NOWRITE,
847 			       N_("Remove is not supported in the %s keytab", ""),
848 			       id->prefix);
849 	return KRB5_KT_NOWRITE;
850     }
851     return (*id->remove)(context, id, entry);
852 }
853 
854 /**
855  * Return true if the keytab exists and have entries
856  *
857  * @param context a Keberos context.
858  * @param id a keytab.
859  *
860  * @return Return an error code or 0, see krb5_get_error_message().
861  *
862  * @ingroup krb5_keytab
863  */
864 
865 KRB5_LIB_FUNCTION krb5_boolean KRB5_LIB_CALL
krb5_kt_have_content(krb5_context context,krb5_keytab id)866 krb5_kt_have_content(krb5_context context,
867 		     krb5_keytab id)
868 {
869     krb5_keytab_entry entry;
870     krb5_kt_cursor cursor;
871     krb5_error_code ret;
872     char *name;
873 
874     ret = krb5_kt_start_seq_get(context, id, &cursor);
875     if (ret)
876 	goto notfound;
877 
878     ret = krb5_kt_next_entry(context, id, &entry, &cursor);
879     krb5_kt_end_seq_get(context, id, &cursor);
880     if (ret)
881 	goto notfound;
882 
883     krb5_kt_free_entry(context, &entry);
884 
885     return 0;
886 
887  notfound:
888     ret = krb5_kt_get_full_name(context, id, &name);
889     if (ret == 0) {
890 	krb5_set_error_message(context, KRB5_KT_NOTFOUND,
891 			       N_("No entry in keytab: %s", ""), name);
892 	free(name);
893     }
894     return KRB5_KT_NOTFOUND;
895 }
896