2 * Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.
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
11 * ECDH/ECDSA low level APIs are deprecated for public use, but still ok for
14 #include "internal/deprecated.h"
16 #include <openssl/core_numbers.h>
17 #include <openssl/core_names.h>
18 #include <openssl/bn.h>
19 #include <openssl/ec.h>
20 #include <openssl/objects.h>
21 #include <openssl/params.h>
22 #include "internal/param_build.h"
23 #include "prov/implementations.h"
24 #include "prov/providercommon.h"
26 static OSSL_OP_keymgmt_new_fn ec_newdata;
27 static OSSL_OP_keymgmt_free_fn ec_freedata;
28 static OSSL_OP_keymgmt_get_params_fn ec_get_params;
29 static OSSL_OP_keymgmt_gettable_params_fn ec_gettable_params;
30 static OSSL_OP_keymgmt_set_params_fn ec_set_params;
31 static OSSL_OP_keymgmt_settable_params_fn ec_settable_params;
32 static OSSL_OP_keymgmt_has_fn ec_has;
33 static OSSL_OP_keymgmt_import_fn ec_import;
34 static OSSL_OP_keymgmt_import_types_fn ec_import_types;
35 static OSSL_OP_keymgmt_export_fn ec_export;
36 static OSSL_OP_keymgmt_export_types_fn ec_export_types;
37 static OSSL_OP_keymgmt_query_operation_name_fn ec_query_operation_name;
39 #define EC_POSSIBLE_SELECTIONS \
40 (OSSL_KEYMGMT_SELECT_KEYPAIR | OSSL_KEYMGMT_SELECT_ALL_PARAMETERS )
43 const char *ec_query_operation_name(int operation_id)
45 switch (operation_id) {
49 case OSSL_OP_SIGNATURE:
50 return deflt_signature;
57 int params_to_domparams(EC_KEY *ec, const OSSL_PARAM params[])
59 const OSSL_PARAM *param_ec_name;
61 char *curve_name = NULL;
67 param_ec_name = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_EC_NAME);
68 if (param_ec_name == NULL) {
69 /* explicit parameters */
72 * TODO(3.0): should we support explicit parameters curves?
79 if (!OSSL_PARAM_get_utf8_string(param_ec_name, &curve_name, 0)
81 || (curve_nid = OBJ_sn2nid(curve_name)) == NID_undef)
84 if ((ecg = EC_GROUP_new_by_curve_name(curve_nid)) == NULL)
88 if (!EC_KEY_set_group(ec, ecg))
92 * TODO(3.0): if the group has changed, should we invalidate the private and
99 OPENSSL_free(curve_name);
105 int domparams_to_params(const EC_KEY *ec, OSSL_PARAM_BLD *tmpl)
113 ecg = EC_KEY_get0_group(ec);
117 curve_nid = EC_GROUP_get_curve_name(ecg);
119 if (curve_nid == NID_undef) {
120 /* explicit parameters */
123 * TODO(3.0): should we support explicit parameters curves?
128 const char *curve_name = NULL;
130 if ((curve_name = OBJ_nid2sn(curve_nid)) == NULL)
133 if (!ossl_param_bld_push_utf8_string(tmpl, OSSL_PKEY_PARAM_EC_NAME, curve_name, 0))
141 * Callers of params_to_key MUST make sure that params_to_domparams has been
144 * This function only imports the bare keypair, domain parameters and other
145 * parameters are imported separately, and domain parameters are required to
149 int params_to_key(EC_KEY *ec, const OSSL_PARAM params[], int include_private)
151 const OSSL_PARAM *param_priv_key, *param_pub_key;
152 BIGNUM *priv_key = NULL;
153 unsigned char *pub_key = NULL;
155 const EC_GROUP *ecg = NULL;
156 EC_POINT *pub_point = NULL;
159 ecg = EC_KEY_get0_group(ec);
164 OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_PRIV_KEY);
166 OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_PUB_KEY);
169 * We want to have at least a public key either way, so we end up
170 * requiring it unconditionally.
172 if (param_pub_key == NULL
173 || !OSSL_PARAM_get_octet_string(param_pub_key,
174 (void **)&pub_key, 0, &pub_key_len)
175 || (pub_point = EC_POINT_new(ecg)) == NULL
176 || !EC_POINT_oct2point(ecg, pub_point,
177 pub_key, pub_key_len, NULL))
180 if (param_priv_key != NULL && include_private
181 && !OSSL_PARAM_get_BN(param_priv_key, &priv_key))
185 && !EC_KEY_set_private_key(ec, priv_key))
188 if (!EC_KEY_set_public_key(ec, pub_point))
194 BN_clear_free(priv_key);
195 OPENSSL_free(pub_key);
196 EC_POINT_free(pub_point);
201 * Callers of key_to_params MUST make sure that domparams_to_params is also
204 * This function only exports the bare keypair, domain parameters and other
205 * parameters are exported separately.
208 int key_to_params(const EC_KEY *eckey, OSSL_PARAM_BLD *tmpl, int include_private)
210 const BIGNUM *priv_key = NULL;
211 const EC_POINT *pub_point = NULL;
212 const EC_GROUP *ecg = NULL;
213 unsigned char *pub_key = NULL;
214 size_t pub_key_len = 0;
220 ecg = EC_KEY_get0_group(eckey);
221 priv_key = EC_KEY_get0_private_key(eckey);
222 pub_point = EC_KEY_get0_public_key(eckey);
224 /* group and public_key must be present, priv_key is optional */
225 if (ecg == NULL || pub_point == NULL)
227 if ((pub_key_len = EC_POINT_point2buf(ecg, pub_point,
228 POINT_CONVERSION_COMPRESSED,
229 &pub_key, NULL)) == 0)
232 if (!ossl_param_bld_push_octet_string(tmpl,
233 OSSL_PKEY_PARAM_PUB_KEY,
234 pub_key, pub_key_len))
237 if (priv_key != NULL && include_private
238 && !ossl_param_bld_push_BN(tmpl,
239 OSSL_PKEY_PARAM_PRIV_KEY,
246 OPENSSL_free(pub_key);
251 int ec_set_param_ecdh_cofactor_mode(EC_KEY *ec, const OSSL_PARAM *p)
253 const EC_GROUP *ecg = EC_KEY_get0_group(ec);
254 const BIGNUM *cofactor;
257 if (!OSSL_PARAM_get_int(p, &mode))
261 * mode can be only 0 for disable, or 1 for enable here.
263 * This is in contrast with the same parameter on an ECDH EVP_PKEY_CTX that
264 * also supports mode == -1 with the meaning of "reset to the default for
265 * the associated key".
267 if (mode < 0 || mode > 1)
270 if ((cofactor = EC_GROUP_get0_cofactor(ecg)) == NULL )
273 /* ECDH cofactor mode has no effect if cofactor is 1 */
274 if (BN_is_one(cofactor))
278 EC_KEY_set_flags(ec, EC_FLAG_COFACTOR_ECDH);
280 EC_KEY_clear_flags(ec, EC_FLAG_COFACTOR_ECDH);
286 int params_to_otherparams(EC_KEY *ec, const OSSL_PARAM params[])
293 p = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_USE_COFACTOR_ECDH);
294 if (p != NULL && !ec_set_param_ecdh_cofactor_mode(ec, p))
301 int otherparams_to_params(const EC_KEY *ec, OSSL_PARAM_BLD *tmpl)
303 int ecdh_cofactor_mode = 0;
309 (EC_KEY_get_flags(ec) & EC_FLAG_COFACTOR_ECDH) ? 1 : 0;
310 if (!ossl_param_bld_push_int(tmpl,
311 OSSL_PKEY_PARAM_USE_COFACTOR_ECDH,
319 void *ec_newdata(void *provctx)
325 void ec_freedata(void *keydata)
327 EC_KEY_free(keydata);
331 int ec_has(void *keydata, int selection)
333 EC_KEY *ec = keydata;
336 if ((selection & EC_POSSIBLE_SELECTIONS) != 0)
339 if ((selection & OSSL_KEYMGMT_SELECT_PUBLIC_KEY) != 0)
340 ok = ok && (EC_KEY_get0_public_key(ec) != NULL);
341 if ((selection & OSSL_KEYMGMT_SELECT_PRIVATE_KEY) != 0)
342 ok = ok && (EC_KEY_get0_private_key(ec) != NULL);
343 if ((selection & OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS) != 0)
344 ok = ok && (EC_KEY_get0_group(ec) != NULL);
346 * We consider OSSL_KEYMGMT_SELECT_OTHER_PARAMETERS to always be available,
347 * so no extra check is needed other than the previous one against
348 * EC_POSSIBLE_SELECTIONS.
355 int ec_import(void *keydata, int selection, const OSSL_PARAM params[])
357 EC_KEY *ec = keydata;
364 * In this implementation, we can export/import only keydata in the
365 * following combinations:
366 * - domain parameters only
367 * - public key with associated domain parameters (+optional other params)
368 * - private key with associated public key and domain parameters
369 * (+optional other params)
372 * - domain parameters must always be requested
373 * - private key must be requested alongside public key
374 * - other parameters must be requested only alongside a key
376 if ((selection & OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS) == 0)
378 if ((selection & OSSL_KEYMGMT_SELECT_PRIVATE_KEY) != 0
379 && (selection & OSSL_KEYMGMT_SELECT_PUBLIC_KEY) == 0)
381 if ((selection & OSSL_KEYMGMT_SELECT_OTHER_PARAMETERS) != 0
382 && (selection & OSSL_KEYMGMT_SELECT_KEYPAIR) == 0)
385 if ((selection & OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS) != 0)
386 ok = ok && params_to_domparams(ec, params);
387 if ((selection & OSSL_KEYMGMT_SELECT_KEYPAIR) != 0) {
388 int include_private =
389 selection & OSSL_KEYMGMT_SELECT_PRIVATE_KEY ? 1 : 0;
391 ok = ok && params_to_key(ec, params, include_private);
393 if ((selection & OSSL_KEYMGMT_SELECT_OTHER_PARAMETERS) != 0)
394 ok = ok && params_to_otherparams(ec, params);
400 int ec_export(void *keydata, int selection, OSSL_CALLBACK *param_cb,
403 EC_KEY *ec = keydata;
405 OSSL_PARAM *params = NULL;
412 * In this implementation, we can export/import only keydata in the
413 * following combinations:
414 * - domain parameters only
415 * - public key with associated domain parameters (+optional other params)
416 * - private key with associated public key and domain parameters
417 * (+optional other params)
420 * - domain parameters must always be requested
421 * - private key must be requested alongside public key
422 * - other parameters must be requested only alongside a key
424 if ((selection & OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS) == 0)
426 if ((selection & OSSL_KEYMGMT_SELECT_PRIVATE_KEY) != 0
427 && (selection & OSSL_KEYMGMT_SELECT_PUBLIC_KEY) == 0)
429 if ((selection & OSSL_KEYMGMT_SELECT_OTHER_PARAMETERS) != 0
430 && (selection & OSSL_KEYMGMT_SELECT_KEYPAIR) == 0)
433 ossl_param_bld_init(&tmpl);
435 if ((selection & OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS) != 0)
436 ok = ok && domparams_to_params(ec, &tmpl);
437 if ((selection & OSSL_KEYMGMT_SELECT_KEYPAIR) != 0) {
438 int include_private =
439 selection & OSSL_KEYMGMT_SELECT_PRIVATE_KEY ? 1 : 0;
441 ok = ok && key_to_params(ec, &tmpl, include_private);
443 if ((selection & OSSL_KEYMGMT_SELECT_OTHER_PARAMETERS) != 0)
444 ok = ok && otherparams_to_params(ec, &tmpl);
447 || (params = ossl_param_bld_to_param(&tmpl)) == NULL)
450 ok = param_cb(params, cbarg);
451 ossl_param_bld_free(params);
455 /* IMEXPORT = IMPORT + EXPORT */
457 # define EC_IMEXPORTABLE_DOM_PARAMETERS \
458 OSSL_PARAM_utf8_string(OSSL_PKEY_PARAM_EC_NAME, NULL, 0)
459 # define EC_IMEXPORTABLE_PUBLIC_KEY \
460 OSSL_PARAM_octet_string(OSSL_PKEY_PARAM_PUB_KEY, NULL, 0)
461 # define EC_IMEXPORTABLE_PRIVATE_KEY \
462 OSSL_PARAM_BN(OSSL_PKEY_PARAM_PRIV_KEY, NULL, 0)
463 # define EC_IMEXPORTABLE_OTHER_PARAMETERS \
464 OSSL_PARAM_int(OSSL_PKEY_PARAM_USE_COFACTOR_ECDH, NULL)
467 * Include all the possible combinations of OSSL_PARAM arrays for
468 * ec_imexport_types().
470 * They are in a separate file as it is ~100 lines of unreadable and
471 * uninteresting machine generated stuff.
473 * TODO(3.0): the generated list looks quite ugly, as to cover all possible
474 * combinations of the bits in `selection`, it also includes combinations that
475 * are not really useful: we might want to consider alternatives to this
478 #include "ec_kmgmt_imexport.inc"
481 const OSSL_PARAM *ec_imexport_types(int selection)
485 if ((selection & OSSL_KEYMGMT_SELECT_PRIVATE_KEY) != 0)
487 if ((selection & OSSL_KEYMGMT_SELECT_PUBLIC_KEY) != 0)
489 if ((selection & OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS) != 0)
491 if ((selection & OSSL_KEYMGMT_SELECT_OTHER_PARAMETERS) != 0)
493 return ec_types[type_select];
497 const OSSL_PARAM *ec_import_types(int selection)
499 return ec_imexport_types(selection);
503 const OSSL_PARAM *ec_export_types(int selection)
505 return ec_imexport_types(selection);
509 int ec_get_params(void *key, OSSL_PARAM params[])
512 const EC_GROUP *ecg = NULL;
515 ecg = EC_KEY_get0_group(eck);
519 if ((p = OSSL_PARAM_locate(params, OSSL_PKEY_PARAM_MAX_SIZE)) != NULL
520 && !OSSL_PARAM_set_int(p, ECDSA_size(eck)))
522 if ((p = OSSL_PARAM_locate(params, OSSL_PKEY_PARAM_BITS)) != NULL
523 && !OSSL_PARAM_set_int(p, EC_GROUP_order_bits(ecg)))
525 if ((p = OSSL_PARAM_locate(params, OSSL_PKEY_PARAM_SECURITY_BITS)) != NULL) {
526 int ecbits, sec_bits;
528 ecbits = EC_GROUP_order_bits(ecg);
531 * The following estimates are based on the values published
532 * in Table 2 of "NIST Special Publication 800-57 Part 1 Revision 4"
533 * at http://dx.doi.org/10.6028/NIST.SP.800-57pt1r4 .
535 * Note that the above reference explicitly categorizes algorithms in a
536 * discrete set of values {80, 112, 128, 192, 256}, and that it is
537 * relevant only for NIST approved Elliptic Curves, while OpenSSL
538 * applies the same logic also to other curves.
540 * Classifications produced by other standardazing bodies might differ,
541 * so the results provided for "bits of security" by this provider are
542 * to be considered merely indicative, and it is the users'
543 * responsibility to compare these values against the normative
544 * references that may be relevant for their intent and purposes.
548 else if (ecbits >= 384)
550 else if (ecbits >= 256)
552 else if (ecbits >= 224)
554 else if (ecbits >= 160)
557 sec_bits = ecbits / 2;
559 if (!OSSL_PARAM_set_int(p, sec_bits))
563 p = OSSL_PARAM_locate(params, OSSL_PKEY_PARAM_USE_COFACTOR_ECDH);
565 int ecdh_cofactor_mode = 0;
568 (EC_KEY_get_flags(eck) & EC_FLAG_COFACTOR_ECDH) ? 1 : 0;
570 if (!OSSL_PARAM_set_int(p, ecdh_cofactor_mode))
577 static const OSSL_PARAM ec_known_gettable_params[] = {
578 OSSL_PARAM_int(OSSL_PKEY_PARAM_BITS, NULL),
579 OSSL_PARAM_int(OSSL_PKEY_PARAM_SECURITY_BITS, NULL),
580 OSSL_PARAM_int(OSSL_PKEY_PARAM_MAX_SIZE, NULL),
581 OSSL_PARAM_int(OSSL_PKEY_PARAM_USE_COFACTOR_ECDH, NULL),
586 const OSSL_PARAM *ec_gettable_params(void)
588 return ec_known_gettable_params;
591 static const OSSL_PARAM ec_known_settable_params[] = {
592 OSSL_PARAM_int(OSSL_PKEY_PARAM_USE_COFACTOR_ECDH, NULL),
597 const OSSL_PARAM *ec_settable_params(void)
599 return ec_known_settable_params;
603 int ec_set_params(void *key, const OSSL_PARAM params[])
608 p = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_USE_COFACTOR_ECDH);
609 if (p != NULL && !ec_set_param_ecdh_cofactor_mode(eck, p))
615 const OSSL_DISPATCH ec_keymgmt_functions[] = {
616 { OSSL_FUNC_KEYMGMT_NEW, (void (*)(void))ec_newdata },
617 { OSSL_FUNC_KEYMGMT_FREE, (void (*)(void))ec_freedata },
618 { OSSL_FUNC_KEYMGMT_GET_PARAMS, (void (*) (void))ec_get_params },
619 { OSSL_FUNC_KEYMGMT_GETTABLE_PARAMS, (void (*) (void))ec_gettable_params },
620 { OSSL_FUNC_KEYMGMT_SET_PARAMS, (void (*) (void))ec_set_params },
621 { OSSL_FUNC_KEYMGMT_SETTABLE_PARAMS, (void (*) (void))ec_settable_params },
622 { OSSL_FUNC_KEYMGMT_HAS, (void (*)(void))ec_has },
623 { OSSL_FUNC_KEYMGMT_IMPORT, (void (*)(void))ec_import },
624 { OSSL_FUNC_KEYMGMT_IMPORT_TYPES, (void (*)(void))ec_import_types },
625 { OSSL_FUNC_KEYMGMT_EXPORT, (void (*)(void))ec_export },
626 { OSSL_FUNC_KEYMGMT_EXPORT_TYPES, (void (*)(void))ec_export_types },
627 { OSSL_FUNC_KEYMGMT_QUERY_OPERATION_NAME,
628 (void (*)(void))ec_query_operation_name },