1 /*
2 * Copyright 2019-2022 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10 #include <openssl/core_names.h>
11 #include "internal/cryptlib.h"
12 #include "internal/nelem.h"
13 #include "crypto/evp.h"
14 #include "internal/core.h"
15 #include "internal/provider.h"
16 #include "evp_local.h"
17
18 /*
19 * match_type() checks if two EVP_KEYMGMT are matching key types. This
20 * function assumes that the caller has made all the necessary NULL checks.
21 */
match_type(const EVP_KEYMGMT * keymgmt1,const EVP_KEYMGMT * keymgmt2)22 static int match_type(const EVP_KEYMGMT *keymgmt1, const EVP_KEYMGMT *keymgmt2)
23 {
24 const char *name2 = EVP_KEYMGMT_get0_name(keymgmt2);
25
26 return EVP_KEYMGMT_is_a(keymgmt1, name2);
27 }
28
evp_keymgmt_util_try_import(const OSSL_PARAM params[],void * arg)29 int evp_keymgmt_util_try_import(const OSSL_PARAM params[], void *arg)
30 {
31 struct evp_keymgmt_util_try_import_data_st *data = arg;
32 int delete_on_error = 0;
33
34 /* Just in time creation of keydata */
35 if (data->keydata == NULL) {
36 if ((data->keydata = evp_keymgmt_newdata(data->keymgmt)) == NULL) {
37 ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);
38 return 0;
39 }
40 delete_on_error = 1;
41 }
42
43 /*
44 * It's fine if there was no data to transfer, we just end up with an
45 * empty destination key.
46 */
47 if (params[0].key == NULL)
48 return 1;
49
50 if (evp_keymgmt_import(data->keymgmt, data->keydata, data->selection,
51 params))
52 return 1;
53 if (delete_on_error) {
54 evp_keymgmt_freedata(data->keymgmt, data->keydata);
55 data->keydata = NULL;
56 }
57 return 0;
58 }
59
evp_keymgmt_util_assign_pkey(EVP_PKEY * pkey,EVP_KEYMGMT * keymgmt,void * keydata)60 int evp_keymgmt_util_assign_pkey(EVP_PKEY *pkey, EVP_KEYMGMT *keymgmt,
61 void *keydata)
62 {
63 if (pkey == NULL || keymgmt == NULL || keydata == NULL
64 || !EVP_PKEY_set_type_by_keymgmt(pkey, keymgmt)) {
65 ERR_raise(ERR_LIB_EVP, ERR_R_INTERNAL_ERROR);
66 return 0;
67 }
68 pkey->keydata = keydata;
69 evp_keymgmt_util_cache_keyinfo(pkey);
70 return 1;
71 }
72
evp_keymgmt_util_make_pkey(EVP_KEYMGMT * keymgmt,void * keydata)73 EVP_PKEY *evp_keymgmt_util_make_pkey(EVP_KEYMGMT *keymgmt, void *keydata)
74 {
75 EVP_PKEY *pkey = NULL;
76
77 if (keymgmt == NULL
78 || keydata == NULL
79 || (pkey = EVP_PKEY_new()) == NULL
80 || !evp_keymgmt_util_assign_pkey(pkey, keymgmt, keydata)) {
81 EVP_PKEY_free(pkey);
82 return NULL;
83 }
84 return pkey;
85 }
86
evp_keymgmt_util_export(const EVP_PKEY * pk,int selection,OSSL_CALLBACK * export_cb,void * export_cbarg)87 int evp_keymgmt_util_export(const EVP_PKEY *pk, int selection,
88 OSSL_CALLBACK *export_cb, void *export_cbarg)
89 {
90 if (pk == NULL || export_cb == NULL)
91 return 0;
92 return evp_keymgmt_export(pk->keymgmt, pk->keydata, selection,
93 export_cb, export_cbarg);
94 }
95
evp_keymgmt_util_export_to_provider(EVP_PKEY * pk,EVP_KEYMGMT * keymgmt,int selection)96 void *evp_keymgmt_util_export_to_provider(EVP_PKEY *pk, EVP_KEYMGMT *keymgmt,
97 int selection)
98 {
99 struct evp_keymgmt_util_try_import_data_st import_data;
100 OP_CACHE_ELEM *op;
101
102 /* Export to where? */
103 if (keymgmt == NULL)
104 return NULL;
105
106 /* If we have an unassigned key, give up */
107 if (pk->keydata == NULL)
108 return NULL;
109
110 /*
111 * If |keymgmt| matches the "origin" |keymgmt|, there is no more to do.
112 * The "origin" is determined by the |keymgmt| pointers being identical
113 * or when the provider and the name ID match. The latter case handles the
114 * situation where the fetch cache is flushed and a "new" key manager is
115 * created.
116 */
117 if (pk->keymgmt == keymgmt
118 || (pk->keymgmt->name_id == keymgmt->name_id
119 && pk->keymgmt->prov == keymgmt->prov))
120 return pk->keydata;
121
122 if (!CRYPTO_THREAD_read_lock(pk->lock))
123 return NULL;
124 /*
125 * If the provider native "origin" hasn't changed since last time, we
126 * try to find our keymgmt in the operation cache. If it has changed
127 * and our keymgmt isn't found, we will clear the cache further down.
128 */
129 if (pk->dirty_cnt == pk->dirty_cnt_copy) {
130 /* If this key is already exported to |keymgmt|, no more to do */
131 op = evp_keymgmt_util_find_operation_cache(pk, keymgmt, selection);
132 if (op != NULL && op->keymgmt != NULL) {
133 void *ret = op->keydata;
134
135 CRYPTO_THREAD_unlock(pk->lock);
136 return ret;
137 }
138 }
139 CRYPTO_THREAD_unlock(pk->lock);
140
141 /* If the "origin" |keymgmt| doesn't support exporting, give up */
142 if (pk->keymgmt->export == NULL)
143 return NULL;
144
145 /*
146 * Make sure that the type of the keymgmt to export to matches the type
147 * of the "origin"
148 */
149 if (!ossl_assert(match_type(pk->keymgmt, keymgmt)))
150 return NULL;
151
152 /*
153 * We look at the already cached provider keys, and import from the
154 * first that supports it (i.e. use its export function), and export
155 * the imported data to the new provider.
156 */
157
158 /* Setup for the export callback */
159 import_data.keydata = NULL; /* evp_keymgmt_util_try_import will create it */
160 import_data.keymgmt = keymgmt;
161 import_data.selection = selection;
162
163 /*
164 * The export function calls the callback (evp_keymgmt_util_try_import),
165 * which does the import for us. If successful, we're done.
166 */
167 if (!evp_keymgmt_util_export(pk, selection,
168 &evp_keymgmt_util_try_import, &import_data))
169 /* If there was an error, bail out */
170 return NULL;
171
172 if (!CRYPTO_THREAD_write_lock(pk->lock)) {
173 evp_keymgmt_freedata(keymgmt, import_data.keydata);
174 return NULL;
175 }
176 /* Check to make sure some other thread didn't get there first */
177 op = evp_keymgmt_util_find_operation_cache(pk, keymgmt, selection);
178 if (op != NULL && op->keydata != NULL) {
179 void *ret = op->keydata;
180
181 CRYPTO_THREAD_unlock(pk->lock);
182
183 /*
184 * Another thread seemms to have already exported this so we abandon
185 * all the work we just did.
186 */
187 evp_keymgmt_freedata(keymgmt, import_data.keydata);
188
189 return ret;
190 }
191
192 /*
193 * If the dirty counter changed since last time, then clear the
194 * operation cache. In that case, we know that |i| is zero.
195 */
196 if (pk->dirty_cnt != pk->dirty_cnt_copy)
197 evp_keymgmt_util_clear_operation_cache(pk, 0);
198
199 /* Add the new export to the operation cache */
200 if (!evp_keymgmt_util_cache_keydata(pk, keymgmt, import_data.keydata,
201 selection)) {
202 CRYPTO_THREAD_unlock(pk->lock);
203 evp_keymgmt_freedata(keymgmt, import_data.keydata);
204 return NULL;
205 }
206
207 /* Synchronize the dirty count */
208 pk->dirty_cnt_copy = pk->dirty_cnt;
209
210 CRYPTO_THREAD_unlock(pk->lock);
211
212 return import_data.keydata;
213 }
214
op_cache_free(OP_CACHE_ELEM * e)215 static void op_cache_free(OP_CACHE_ELEM *e)
216 {
217 evp_keymgmt_freedata(e->keymgmt, e->keydata);
218 EVP_KEYMGMT_free(e->keymgmt);
219 OPENSSL_free(e);
220 }
221
evp_keymgmt_util_clear_operation_cache(EVP_PKEY * pk,int locking)222 int evp_keymgmt_util_clear_operation_cache(EVP_PKEY *pk, int locking)
223 {
224 if (pk != NULL) {
225 if (locking && pk->lock != NULL && !CRYPTO_THREAD_write_lock(pk->lock))
226 return 0;
227 sk_OP_CACHE_ELEM_pop_free(pk->operation_cache, op_cache_free);
228 pk->operation_cache = NULL;
229 if (locking && pk->lock != NULL)
230 CRYPTO_THREAD_unlock(pk->lock);
231 }
232
233 return 1;
234 }
235
evp_keymgmt_util_find_operation_cache(EVP_PKEY * pk,EVP_KEYMGMT * keymgmt,int selection)236 OP_CACHE_ELEM *evp_keymgmt_util_find_operation_cache(EVP_PKEY *pk,
237 EVP_KEYMGMT *keymgmt,
238 int selection)
239 {
240 int i, end = sk_OP_CACHE_ELEM_num(pk->operation_cache);
241 OP_CACHE_ELEM *p;
242
243 /*
244 * A comparison and sk_P_CACHE_ELEM_find() are avoided to not cause
245 * problems when we've only a read lock.
246 */
247 for (i = 0; i < end; i++) {
248 p = sk_OP_CACHE_ELEM_value(pk->operation_cache, i);
249 if (keymgmt == p->keymgmt && (p->selection & selection) == selection)
250 return p;
251 }
252 return NULL;
253 }
254
evp_keymgmt_util_cache_keydata(EVP_PKEY * pk,EVP_KEYMGMT * keymgmt,void * keydata,int selection)255 int evp_keymgmt_util_cache_keydata(EVP_PKEY *pk, EVP_KEYMGMT *keymgmt,
256 void *keydata, int selection)
257 {
258 OP_CACHE_ELEM *p = NULL;
259
260 if (keydata != NULL) {
261 if (pk->operation_cache == NULL) {
262 pk->operation_cache = sk_OP_CACHE_ELEM_new_null();
263 if (pk->operation_cache == NULL)
264 return 0;
265 }
266
267 p = OPENSSL_malloc(sizeof(*p));
268 if (p == NULL)
269 return 0;
270 p->keydata = keydata;
271 p->keymgmt = keymgmt;
272 p->selection = selection;
273
274 if (!EVP_KEYMGMT_up_ref(keymgmt)) {
275 OPENSSL_free(p);
276 return 0;
277 }
278
279 if (!sk_OP_CACHE_ELEM_push(pk->operation_cache, p)) {
280 EVP_KEYMGMT_free(keymgmt);
281 OPENSSL_free(p);
282 return 0;
283 }
284 }
285 return 1;
286 }
287
evp_keymgmt_util_cache_keyinfo(EVP_PKEY * pk)288 void evp_keymgmt_util_cache_keyinfo(EVP_PKEY *pk)
289 {
290 /*
291 * Cache information about the provider "origin" key.
292 *
293 * This services functions like EVP_PKEY_get_size, EVP_PKEY_get_bits, etc
294 */
295 if (pk->keydata != NULL) {
296 int bits = 0;
297 int security_bits = 0;
298 int size = 0;
299 OSSL_PARAM params[4];
300
301 params[0] = OSSL_PARAM_construct_int(OSSL_PKEY_PARAM_BITS, &bits);
302 params[1] = OSSL_PARAM_construct_int(OSSL_PKEY_PARAM_SECURITY_BITS,
303 &security_bits);
304 params[2] = OSSL_PARAM_construct_int(OSSL_PKEY_PARAM_MAX_SIZE, &size);
305 params[3] = OSSL_PARAM_construct_end();
306 if (evp_keymgmt_get_params(pk->keymgmt, pk->keydata, params)) {
307 pk->cache.size = size;
308 pk->cache.bits = bits;
309 pk->cache.security_bits = security_bits;
310 }
311 }
312 }
313
evp_keymgmt_util_fromdata(EVP_PKEY * target,EVP_KEYMGMT * keymgmt,int selection,const OSSL_PARAM params[])314 void *evp_keymgmt_util_fromdata(EVP_PKEY *target, EVP_KEYMGMT *keymgmt,
315 int selection, const OSSL_PARAM params[])
316 {
317 void *keydata = NULL;
318
319 if ((keydata = evp_keymgmt_newdata(keymgmt)) == NULL
320 || !evp_keymgmt_import(keymgmt, keydata, selection, params)
321 || !evp_keymgmt_util_assign_pkey(target, keymgmt, keydata)) {
322 evp_keymgmt_freedata(keymgmt, keydata);
323 keydata = NULL;
324 }
325 return keydata;
326 }
327
evp_keymgmt_util_has(EVP_PKEY * pk,int selection)328 int evp_keymgmt_util_has(EVP_PKEY *pk, int selection)
329 {
330 /* Check if key is even assigned */
331 if (pk->keymgmt == NULL)
332 return 0;
333
334 return evp_keymgmt_has(pk->keymgmt, pk->keydata, selection);
335 }
336
337 /*
338 * evp_keymgmt_util_match() doesn't just look at the provider side "origin",
339 * but also in the operation cache to see if there's any common keymgmt that
340 * supplies OP_keymgmt_match.
341 *
342 * evp_keymgmt_util_match() adheres to the return values that EVP_PKEY_eq()
343 * and EVP_PKEY_parameters_eq() return, i.e.:
344 *
345 * 1 same key
346 * 0 not same key
347 * -1 not same key type
348 * -2 unsupported operation
349 */
evp_keymgmt_util_match(EVP_PKEY * pk1,EVP_PKEY * pk2,int selection)350 int evp_keymgmt_util_match(EVP_PKEY *pk1, EVP_PKEY *pk2, int selection)
351 {
352 EVP_KEYMGMT *keymgmt1 = NULL, *keymgmt2 = NULL;
353 void *keydata1 = NULL, *keydata2 = NULL;
354
355 if (pk1 == NULL || pk2 == NULL) {
356 if (pk1 == NULL && pk2 == NULL)
357 return 1;
358 return 0;
359 }
360
361 keymgmt1 = pk1->keymgmt;
362 keydata1 = pk1->keydata;
363 keymgmt2 = pk2->keymgmt;
364 keydata2 = pk2->keydata;
365
366 if (keymgmt1 != keymgmt2) {
367 /*
368 * The condition for a successful cross export is that the
369 * keydata to be exported is NULL (typed, but otherwise empty
370 * EVP_PKEY), or that it was possible to export it with
371 * evp_keymgmt_util_export_to_provider().
372 *
373 * We use |ok| to determine if it's ok to cross export one way,
374 * but also to determine if we should attempt a cross export
375 * the other way. There's no point doing it both ways.
376 */
377 int ok = 0;
378
379 /* Complex case, where the keymgmt differ */
380 if (keymgmt1 != NULL
381 && keymgmt2 != NULL
382 && !match_type(keymgmt1, keymgmt2)) {
383 ERR_raise(ERR_LIB_EVP, EVP_R_DIFFERENT_KEY_TYPES);
384 return -1; /* Not the same type */
385 }
386
387 /*
388 * The key types are determined to match, so we try cross export,
389 * but only to keymgmt's that supply a matching function.
390 */
391 if (keymgmt2 != NULL
392 && keymgmt2->match != NULL) {
393 void *tmp_keydata = NULL;
394
395 ok = 1;
396 if (keydata1 != NULL) {
397 tmp_keydata =
398 evp_keymgmt_util_export_to_provider(pk1, keymgmt2,
399 selection);
400 ok = (tmp_keydata != NULL);
401 }
402 if (ok) {
403 keymgmt1 = keymgmt2;
404 keydata1 = tmp_keydata;
405 }
406 }
407 /*
408 * If we've successfully cross exported one way, there's no point
409 * doing it the other way, hence the |!ok| check.
410 */
411 if (!ok
412 && keymgmt1 != NULL
413 && keymgmt1->match != NULL) {
414 void *tmp_keydata = NULL;
415
416 ok = 1;
417 if (keydata2 != NULL) {
418 tmp_keydata =
419 evp_keymgmt_util_export_to_provider(pk2, keymgmt1,
420 selection);
421 ok = (tmp_keydata != NULL);
422 }
423 if (ok) {
424 keymgmt2 = keymgmt1;
425 keydata2 = tmp_keydata;
426 }
427 }
428 }
429
430 /* If we still don't have matching keymgmt implementations, we give up */
431 if (keymgmt1 != keymgmt2)
432 return -2;
433
434 /* If both keydata are NULL, then they're the same key */
435 if (keydata1 == NULL && keydata2 == NULL)
436 return 1;
437 /* If only one of the keydata is NULL, then they're different keys */
438 if (keydata1 == NULL || keydata2 == NULL)
439 return 0;
440 /* If both keydata are non-NULL, we let the backend decide */
441 return evp_keymgmt_match(keymgmt1, keydata1, keydata2, selection);
442 }
443
evp_keymgmt_util_copy(EVP_PKEY * to,EVP_PKEY * from,int selection)444 int evp_keymgmt_util_copy(EVP_PKEY *to, EVP_PKEY *from, int selection)
445 {
446 /* Save copies of pointers we want to play with without affecting |to| */
447 EVP_KEYMGMT *to_keymgmt = to->keymgmt;
448 void *to_keydata = to->keydata, *alloc_keydata = NULL;
449
450 /* An unassigned key can't be copied */
451 if (from == NULL || from->keydata == NULL)
452 return 0;
453
454 /*
455 * If |to| is unassigned, ensure it gets the same KEYMGMT as |from|,
456 * Note that the final setting of KEYMGMT is done further down, with
457 * EVP_PKEY_set_type_by_keymgmt(); we don't want to do that prematurely.
458 */
459 if (to_keymgmt == NULL)
460 to_keymgmt = from->keymgmt;
461
462 if (to_keymgmt == from->keymgmt && to_keymgmt->dup != NULL
463 && to_keydata == NULL) {
464 to_keydata = alloc_keydata = evp_keymgmt_dup(to_keymgmt,
465 from->keydata,
466 selection);
467 if (to_keydata == NULL)
468 return 0;
469 } else if (match_type(to_keymgmt, from->keymgmt)) {
470 struct evp_keymgmt_util_try_import_data_st import_data;
471
472 import_data.keymgmt = to_keymgmt;
473 import_data.keydata = to_keydata;
474 import_data.selection = selection;
475
476 if (!evp_keymgmt_util_export(from, selection,
477 &evp_keymgmt_util_try_import,
478 &import_data))
479 return 0;
480
481 /*
482 * In case to_keydata was previously unallocated,
483 * evp_keymgmt_util_try_import() may have created it for us.
484 */
485 if (to_keydata == NULL)
486 to_keydata = alloc_keydata = import_data.keydata;
487 } else {
488 ERR_raise(ERR_LIB_EVP, EVP_R_DIFFERENT_KEY_TYPES);
489 return 0;
490 }
491
492 /*
493 * We only need to set the |to| type when its |keymgmt| isn't set.
494 * We can then just set its |keydata| to what we have, which might
495 * be exactly what it had when entering this function.
496 * This is a bit different from using evp_keymgmt_util_assign_pkey(),
497 * which isn't as careful with |to|'s original |keymgmt|, since it's
498 * meant to forcibly reassign an EVP_PKEY no matter what, which is
499 * why we don't use that one here.
500 */
501 if (to->keymgmt == NULL
502 && !EVP_PKEY_set_type_by_keymgmt(to, to_keymgmt)) {
503 evp_keymgmt_freedata(to_keymgmt, alloc_keydata);
504 return 0;
505 }
506 to->keydata = to_keydata;
507 evp_keymgmt_util_cache_keyinfo(to);
508
509 return 1;
510 }
511
evp_keymgmt_util_gen(EVP_PKEY * target,EVP_KEYMGMT * keymgmt,void * genctx,OSSL_CALLBACK * cb,void * cbarg)512 void *evp_keymgmt_util_gen(EVP_PKEY *target, EVP_KEYMGMT *keymgmt,
513 void *genctx, OSSL_CALLBACK *cb, void *cbarg)
514 {
515 void *keydata = NULL;
516
517 if ((keydata = evp_keymgmt_gen(keymgmt, genctx, cb, cbarg)) == NULL
518 || !evp_keymgmt_util_assign_pkey(target, keymgmt, keydata)) {
519 evp_keymgmt_freedata(keymgmt, keydata);
520 keydata = NULL;
521 }
522
523 return keydata;
524 }
525
526 /*
527 * Returns the same numbers as EVP_PKEY_get_default_digest_name()
528 * When the string from the EVP_KEYMGMT implementation is "", we use
529 * SN_undef, since that corresponds to what EVP_PKEY_get_default_nid()
530 * returns for no digest.
531 */
evp_keymgmt_util_get_deflt_digest_name(EVP_KEYMGMT * keymgmt,void * keydata,char * mdname,size_t mdname_sz)532 int evp_keymgmt_util_get_deflt_digest_name(EVP_KEYMGMT *keymgmt,
533 void *keydata,
534 char *mdname, size_t mdname_sz)
535 {
536 OSSL_PARAM params[3];
537 char mddefault[100] = "";
538 char mdmandatory[100] = "";
539 char *result = NULL;
540 int rv = -2;
541
542 params[0] =
543 OSSL_PARAM_construct_utf8_string(OSSL_PKEY_PARAM_DEFAULT_DIGEST,
544 mddefault, sizeof(mddefault));
545 params[1] =
546 OSSL_PARAM_construct_utf8_string(OSSL_PKEY_PARAM_MANDATORY_DIGEST,
547 mdmandatory,
548 sizeof(mdmandatory));
549 params[2] = OSSL_PARAM_construct_end();
550
551 if (!evp_keymgmt_get_params(keymgmt, keydata, params))
552 return 0;
553
554 if (OSSL_PARAM_modified(params + 1)) {
555 if (params[1].return_size <= 1) /* Only a NUL byte */
556 result = SN_undef;
557 else
558 result = mdmandatory;
559 rv = 2;
560 } else if (OSSL_PARAM_modified(params)) {
561 if (params[0].return_size <= 1) /* Only a NUL byte */
562 result = SN_undef;
563 else
564 result = mddefault;
565 rv = 1;
566 }
567 if (rv > 0)
568 OPENSSL_strlcpy(mdname, result, mdname_sz);
569 return rv;
570 }
571
572 /*
573 * If |keymgmt| has the method function |query_operation_name|, use it to get
574 * the name of a supported operation identity. Otherwise, return the keytype,
575 * assuming that it works as a default operation name.
576 */
evp_keymgmt_util_query_operation_name(EVP_KEYMGMT * keymgmt,int op_id)577 const char *evp_keymgmt_util_query_operation_name(EVP_KEYMGMT *keymgmt,
578 int op_id)
579 {
580 const char *name = NULL;
581
582 if (keymgmt != NULL) {
583 if (keymgmt->query_operation_name != NULL)
584 name = keymgmt->query_operation_name(op_id);
585 if (name == NULL)
586 name = EVP_KEYMGMT_get0_name(keymgmt);
587 }
588 return name;
589 }
590