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