xref: /freebsd/crypto/heimdal/lib/krb5/keytab_file.c (revision 5521ff5a4d1929056e7ffc982fac3341ca54df7c)
1 /*
2  * Copyright (c) 1997 - 2001 Kungliga Tekniska H�gskolan
3  * (Royal Institute of Technology, Stockholm, Sweden).
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  *
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.
16  *
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.
20  *
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
31  * SUCH DAMAGE.
32  */
33 
34 #include "krb5_locl.h"
35 
36 RCSID("$Id: keytab_file.c,v 1.8 2001/05/14 06:14:48 assar Exp $");
37 
38 #define KRB5_KT_VNO_1 1
39 #define KRB5_KT_VNO_2 2
40 #define KRB5_KT_VNO   KRB5_KT_VNO_2
41 
42 /* file operations -------------------------------------------- */
43 
44 struct fkt_data {
45     char *filename;
46 };
47 
48 static krb5_error_code
49 krb5_kt_ret_data(krb5_context context,
50 		 krb5_storage *sp,
51 		 krb5_data *data)
52 {
53     int ret;
54     int16_t size;
55     ret = krb5_ret_int16(sp, &size);
56     if(ret)
57 	return ret;
58     data->length = size;
59     data->data = malloc(size);
60     if (data->data == NULL) {
61 	krb5_set_error_string (context, "malloc: out of memory");
62 	return ENOMEM;
63     }
64     ret = sp->fetch(sp, data->data, size);
65     if(ret != size)
66 	return (ret < 0)? errno : KRB5_KT_END;
67     return 0;
68 }
69 
70 static krb5_error_code
71 krb5_kt_ret_string(krb5_context context,
72 		   krb5_storage *sp,
73 		   general_string *data)
74 {
75     int ret;
76     int16_t size;
77     ret = krb5_ret_int16(sp, &size);
78     if(ret)
79 	return ret;
80     *data = malloc(size + 1);
81     if (*data == NULL) {
82 	krb5_set_error_string (context, "malloc: out of memory");
83 	return ENOMEM;
84     }
85     ret = sp->fetch(sp, *data, size);
86     (*data)[size] = '\0';
87     if(ret != size)
88 	return (ret < 0)? errno : KRB5_KT_END;
89     return 0;
90 }
91 
92 static krb5_error_code
93 krb5_kt_store_data(krb5_context context,
94 		   krb5_storage *sp,
95 		   krb5_data data)
96 {
97     int ret;
98     ret = krb5_store_int16(sp, data.length);
99     if(ret < 0)
100 	return ret;
101     ret = sp->store(sp, data.data, data.length);
102     if(ret != data.length){
103 	if(ret < 0)
104 	    return errno;
105 	return KRB5_KT_END;
106     }
107     return 0;
108 }
109 
110 static krb5_error_code
111 krb5_kt_store_string(krb5_storage *sp,
112 		     general_string data)
113 {
114     int ret;
115     size_t len = strlen(data);
116     ret = krb5_store_int16(sp, len);
117     if(ret < 0)
118 	return ret;
119     ret = sp->store(sp, data, len);
120     if(ret != len){
121 	if(ret < 0)
122 	    return errno;
123 	return KRB5_KT_END;
124     }
125     return 0;
126 }
127 
128 static krb5_error_code
129 krb5_kt_ret_keyblock(krb5_context context, krb5_storage *sp, krb5_keyblock *p)
130 {
131     int ret;
132     int16_t tmp;
133 
134     ret = krb5_ret_int16(sp, &tmp); /* keytype + etype */
135     if(ret) return ret;
136     p->keytype = tmp;
137     ret = krb5_kt_ret_data(context, sp, &p->keyvalue);
138     return ret;
139 }
140 
141 static krb5_error_code
142 krb5_kt_store_keyblock(krb5_context context,
143 		       krb5_storage *sp,
144 		       krb5_keyblock *p)
145 {
146     int ret;
147 
148     ret = krb5_store_int16(sp, p->keytype); /* keytype + etype */
149     if(ret) return ret;
150     ret = krb5_kt_store_data(context, sp, p->keyvalue);
151     return ret;
152 }
153 
154 
155 static krb5_error_code
156 krb5_kt_ret_principal(krb5_context context,
157 		      krb5_storage *sp,
158 		      krb5_principal *princ)
159 {
160     int i;
161     int ret;
162     krb5_principal p;
163     int16_t tmp;
164 
165     ALLOC(p, 1);
166     if(p == NULL) {
167 	krb5_set_error_string (context, "malloc: out of memory");
168 	return ENOMEM;
169     }
170 
171     ret = krb5_ret_int16(sp, &tmp);
172     if(ret)
173 	return ret;
174     if (sp->flags & KRB5_STORAGE_PRINCIPAL_WRONG_NUM_COMPONENTS)
175 	tmp--;
176     p->name.name_string.len = tmp;
177     ret = krb5_kt_ret_string(context, sp, &p->realm);
178     if(ret)
179 	return ret;
180     p->name.name_string.val = calloc(p->name.name_string.len,
181 				     sizeof(*p->name.name_string.val));
182     if(p->name.name_string.val == NULL) {
183 	krb5_set_error_string (context, "malloc: out of memory");
184 	return ENOMEM;
185     }
186     for(i = 0; i < p->name.name_string.len; i++){
187 	ret = krb5_kt_ret_string(context, sp, p->name.name_string.val + i);
188 	if(ret)
189 	    return ret;
190     }
191     if (krb5_storage_is_flags(sp, KRB5_STORAGE_PRINCIPAL_NO_NAME_TYPE))
192 	p->name.name_type = KRB5_NT_UNKNOWN;
193     else {
194 	int32_t tmp32;
195 	ret = krb5_ret_int32(sp, &tmp32);
196 	p->name.name_type = tmp32;
197 	if (ret)
198 	    return ret;
199     }
200     *princ = p;
201     return 0;
202 }
203 
204 static krb5_error_code
205 krb5_kt_store_principal(krb5_context context,
206 			krb5_storage *sp,
207 			krb5_principal p)
208 {
209     int i;
210     int ret;
211 
212     if(krb5_storage_is_flags(sp, KRB5_STORAGE_PRINCIPAL_WRONG_NUM_COMPONENTS))
213 	ret = krb5_store_int16(sp, p->name.name_string.len + 1);
214     else
215 	ret = krb5_store_int16(sp, p->name.name_string.len);
216     if(ret) return ret;
217     ret = krb5_kt_store_string(sp, p->realm);
218     if(ret) return ret;
219     for(i = 0; i < p->name.name_string.len; i++){
220 	ret = krb5_kt_store_string(sp, p->name.name_string.val[i]);
221 	if(ret)
222 	    return ret;
223     }
224     if(!krb5_storage_is_flags(sp, KRB5_STORAGE_PRINCIPAL_NO_NAME_TYPE)) {
225 	ret = krb5_store_int32(sp, p->name.name_type);
226 	if(ret)
227 	    return ret;
228     }
229 
230     return 0;
231 }
232 
233 static krb5_error_code
234 fkt_resolve(krb5_context context, const char *name, krb5_keytab id)
235 {
236     struct fkt_data *d;
237 
238     d = malloc(sizeof(*d));
239     if(d == NULL) {
240 	krb5_set_error_string (context, "malloc: out of memory");
241 	return ENOMEM;
242     }
243     d->filename = strdup(name);
244     if(d->filename == NULL) {
245 	free(d);
246 	krb5_set_error_string (context, "malloc: out of memory");
247 	return ENOMEM;
248     }
249     id->data = d;
250     return 0;
251 }
252 
253 static krb5_error_code
254 fkt_close(krb5_context context, krb5_keytab id)
255 {
256     struct fkt_data *d = id->data;
257     free(d->filename);
258     free(d);
259     return 0;
260 }
261 
262 static krb5_error_code
263 fkt_get_name(krb5_context context,
264 	     krb5_keytab id,
265 	     char *name,
266 	     size_t namesize)
267 {
268     /* This function is XXX */
269     struct fkt_data *d = id->data;
270     strlcpy(name, d->filename, namesize);
271     return 0;
272 }
273 
274 static void
275 storage_set_flags(krb5_context context, krb5_storage *sp, int vno)
276 {
277     int flags = 0;
278     switch(vno) {
279     case KRB5_KT_VNO_1:
280 	flags |= KRB5_STORAGE_PRINCIPAL_WRONG_NUM_COMPONENTS;
281 	flags |= KRB5_STORAGE_PRINCIPAL_NO_NAME_TYPE;
282 	flags |= KRB5_STORAGE_HOST_BYTEORDER;
283 	break;
284     case KRB5_KT_VNO_2:
285 	break;
286     default:
287 	krb5_abortx(context,
288 		    "storage_set_flags called with bad vno (%x)", vno);
289     }
290     krb5_storage_set_flags(sp, flags);
291 }
292 
293 static krb5_error_code
294 fkt_start_seq_get_int(krb5_context context,
295 		      krb5_keytab id,
296 		      int flags,
297 		      krb5_kt_cursor *c)
298 {
299     int8_t pvno, tag;
300     krb5_error_code ret;
301     struct fkt_data *d = id->data;
302 
303     c->fd = open (d->filename, flags);
304     if (c->fd < 0) {
305 	ret = errno;
306 	krb5_set_error_string(context, "open(%s): %s", d->filename,
307 			      strerror(ret));
308 	return ret;
309     }
310     c->sp = krb5_storage_from_fd(c->fd);
311     ret = krb5_ret_int8(c->sp, &pvno);
312     if(ret) {
313 	krb5_storage_free(c->sp);
314 	close(c->fd);
315 	return ret;
316     }
317     if(pvno != 5) {
318 	krb5_storage_free(c->sp);
319 	close(c->fd);
320 	krb5_clear_error_string (context);
321 	return KRB5_KEYTAB_BADVNO;
322     }
323     ret = krb5_ret_int8(c->sp, &tag);
324     if (ret) {
325 	krb5_storage_free(c->sp);
326 	close(c->fd);
327 	return ret;
328     }
329     id->version = tag;
330     storage_set_flags(context, c->sp, id->version);
331     return 0;
332 }
333 
334 static krb5_error_code
335 fkt_start_seq_get(krb5_context context,
336 		  krb5_keytab id,
337 		  krb5_kt_cursor *c)
338 {
339     return fkt_start_seq_get_int(context, id, O_RDONLY | O_BINARY, c);
340 }
341 
342 static krb5_error_code
343 fkt_next_entry_int(krb5_context context,
344 		   krb5_keytab id,
345 		   krb5_keytab_entry *entry,
346 		   krb5_kt_cursor *cursor,
347 		   off_t *start,
348 		   off_t *end)
349 {
350     int32_t len;
351     int ret;
352     int8_t tmp8;
353     int32_t tmp32;
354     off_t pos;
355 
356     pos = cursor->sp->seek(cursor->sp, 0, SEEK_CUR);
357 loop:
358     ret = krb5_ret_int32(cursor->sp, &len);
359     if (ret)
360 	return ret;
361     if(len < 0) {
362 	pos = cursor->sp->seek(cursor->sp, -len, SEEK_CUR);
363 	goto loop;
364     }
365     ret = krb5_kt_ret_principal (context, cursor->sp, &entry->principal);
366     if (ret)
367 	goto out;
368     ret = krb5_ret_int32(cursor->sp, &tmp32);
369     entry->timestamp = tmp32;
370     if (ret)
371 	goto out;
372     ret = krb5_ret_int8(cursor->sp, &tmp8);
373     if (ret)
374 	goto out;
375     entry->vno = tmp8;
376     ret = krb5_kt_ret_keyblock (context, cursor->sp, &entry->keyblock);
377     if (ret)
378 	goto out;
379     if(start) *start = pos;
380     if(end) *end = *start + 4 + len;
381  out:
382     cursor->sp->seek(cursor->sp, pos + 4 + len, SEEK_SET);
383     return ret;
384 }
385 
386 static krb5_error_code
387 fkt_next_entry(krb5_context context,
388 	       krb5_keytab id,
389 	       krb5_keytab_entry *entry,
390 	       krb5_kt_cursor *cursor)
391 {
392     return fkt_next_entry_int(context, id, entry, cursor, NULL, NULL);
393 }
394 
395 static krb5_error_code
396 fkt_end_seq_get(krb5_context context,
397 		krb5_keytab id,
398 		krb5_kt_cursor *cursor)
399 {
400     krb5_storage_free(cursor->sp);
401     close(cursor->fd);
402     return 0;
403 }
404 
405 static krb5_error_code
406 fkt_add_entry(krb5_context context,
407 	      krb5_keytab id,
408 	      krb5_keytab_entry *entry)
409 {
410     int ret;
411     int fd;
412     krb5_storage *sp;
413     struct fkt_data *d = id->data;
414     krb5_data keytab;
415     int32_t len;
416 
417     fd = open (d->filename, O_RDWR | O_BINARY);
418     if (fd < 0) {
419 	fd = open (d->filename, O_RDWR | O_CREAT | O_BINARY, 0600);
420 	if (fd < 0) {
421 	    ret = errno;
422 	    krb5_set_error_string(context, "open(%s): %s", d->filename,
423 				  strerror(ret));
424 	    return ret;
425 	}
426 	sp = krb5_storage_from_fd(fd);
427 	ret = krb5_store_int8(sp, 5);
428 	if(ret) {
429 	    krb5_storage_free(sp);
430 	    close(fd);
431 	    return ret;
432 	}
433 	if(id->version == 0)
434 	    id->version = KRB5_KT_VNO;
435 	ret = krb5_store_int8 (sp, id->version);
436 	if (ret) {
437 	    krb5_storage_free(sp);
438 	    close(fd);
439 	    return ret;
440 	}
441 	storage_set_flags(context, sp, id->version);
442     } else {
443 	int8_t pvno, tag;
444 	sp = krb5_storage_from_fd(fd);
445 	ret = krb5_ret_int8(sp, &pvno);
446 	if(ret) {
447 	    krb5_storage_free(sp);
448 	    close(fd);
449 	    return ret;
450 	}
451 	if(pvno != 5) {
452 	    krb5_storage_free(sp);
453 	    close(fd);
454 	    krb5_clear_error_string (context);
455 	    return KRB5_KEYTAB_BADVNO;
456 	}
457 	ret = krb5_ret_int8 (sp, &tag);
458 	if (ret) {
459 	    krb5_storage_free(sp);
460 	    close(fd);
461 	    return ret;
462 	}
463 	id->version = tag;
464 	storage_set_flags(context, sp, id->version);
465     }
466 
467     {
468 	krb5_storage *emem;
469 	emem = krb5_storage_emem();
470 	if(emem == NULL) {
471 	    ret = ENOMEM;
472 	    krb5_set_error_string (context, "malloc: out of memory");
473 	    goto out;
474 	}
475 	ret = krb5_kt_store_principal(context, emem, entry->principal);
476 	if(ret) {
477 	    krb5_storage_free(emem);
478 	    goto out;
479 	}
480 	ret = krb5_store_int32 (emem, entry->timestamp);
481 	if(ret) {
482 	    krb5_storage_free(emem);
483 	    goto out;
484 	}
485 	ret = krb5_store_int8 (emem, entry->vno);
486 	if(ret) {
487 	    krb5_storage_free(emem);
488 	    goto out;
489 	}
490 	ret = krb5_kt_store_keyblock (context, emem, &entry->keyblock);
491 	if(ret) {
492 	    krb5_storage_free(emem);
493 	    goto out;
494 	}
495 	ret = krb5_storage_to_data(emem, &keytab);
496 	krb5_storage_free(emem);
497 	if(ret)
498 	    goto out;
499     }
500 
501     while(1) {
502 	ret = krb5_ret_int32(sp, &len);
503 	if(ret == KRB5_CC_END) {
504 	    len = keytab.length;
505 	    break;
506 	}
507 	if(len < 0) {
508 	    len = -len;
509 	    if(len >= keytab.length) {
510 		sp->seek(sp, -4, SEEK_CUR);
511 		break;
512 	    }
513 	}
514 	sp->seek(sp, len, SEEK_CUR);
515     }
516     ret = krb5_store_int32(sp, len);
517     if(sp->store(sp, keytab.data, keytab.length) < 0)
518 	ret = errno;
519     memset(keytab.data, 0, keytab.length);
520     krb5_data_free(&keytab);
521  out:
522     krb5_storage_free(sp);
523     close(fd);
524     return ret;
525 }
526 
527 static krb5_error_code
528 fkt_remove_entry(krb5_context context,
529 		 krb5_keytab id,
530 		 krb5_keytab_entry *entry)
531 {
532     krb5_keytab_entry e;
533     krb5_kt_cursor cursor;
534     off_t pos_start, pos_end;
535     int found = 0;
536 
537     fkt_start_seq_get_int(context, id, O_RDWR | O_BINARY, &cursor);
538     while(fkt_next_entry_int(context, id, &e, &cursor,
539 			     &pos_start, &pos_end) == 0) {
540 	if(krb5_kt_compare(context, &e, entry->principal,
541 			   entry->vno, entry->keyblock.keytype)) {
542 	    int32_t len;
543 	    unsigned char buf[128];
544 	    found = 1;
545 	    cursor.sp->seek(cursor.sp, pos_start, SEEK_SET);
546 	    len = pos_end - pos_start - 4;
547 	    krb5_store_int32(cursor.sp, -len);
548 	    memset(buf, 0, sizeof(buf));
549 	    while(len > 0) {
550 		cursor.sp->store(cursor.sp, buf, min(len, sizeof(buf)));
551 		len -= min(len, sizeof(buf));
552 	    }
553 	}
554     }
555     krb5_kt_end_seq_get(context, id, &cursor);
556     if (!found) {
557 	krb5_clear_error_string (context);
558 	return KRB5_KT_NOTFOUND;
559     }
560     return 0;
561 }
562 
563 const krb5_kt_ops krb5_fkt_ops = {
564     "FILE",
565     fkt_resolve,
566     fkt_get_name,
567     fkt_close,
568     NULL, /* get */
569     fkt_start_seq_get,
570     fkt_next_entry,
571     fkt_end_seq_get,
572     fkt_add_entry,
573     fkt_remove_entry
574 };
575