]> git.ipfire.org Git - thirdparty/openssl.git/blame - crypto/ec/ecdsa_ossl.c
Convert all {NAME}err() in crypto/ to their corresponding ERR_raise() call
[thirdparty/openssl.git] / crypto / ec / ecdsa_ossl.c
CommitLineData
c6700d27 1/*
33388b44 2 * Copyright 2002-2020 The OpenSSL Project Authors. All Rights Reserved.
4d94ae00 3 *
a7f182b7 4 * Licensed under the Apache License 2.0 (the "License"). You may not use
aa6bb135
RS
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
4d94ae00 8 */
0bee0e62 9
579422c8
P
10/*
11 * ECDSA low level APIs are deprecated for public use, but still ok for
12 * internal use.
13 */
14#include "internal/deprecated.h"
15
a200a817 16#include <string.h>
0bee0e62 17#include <openssl/err.h>
14a7cfb3 18#include <openssl/obj_mac.h>
8a99cb29 19#include <openssl/rand.h>
25f2138b 20#include "crypto/bn.h"
706457b7 21#include "ec_local.h"
190c615d 22
9bf682f6
PS
23int ossl_ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp,
24 BIGNUM **rp)
25{
26 if (eckey->group->meth->ecdsa_sign_setup == NULL) {
9311d0c4 27 ERR_raise(ERR_LIB_EC, EC_R_CURVE_DOES_NOT_SUPPORT_ECDSA);
9bf682f6
PS
28 return 0;
29 }
30
31 return eckey->group->meth->ecdsa_sign_setup(eckey, ctx_in, kinvp, rp);
32}
33
34ECDSA_SIG *ossl_ecdsa_sign_sig(const unsigned char *dgst, int dgst_len,
35 const BIGNUM *in_kinv, const BIGNUM *in_r,
36 EC_KEY *eckey)
37{
38 if (eckey->group->meth->ecdsa_sign_sig == NULL) {
9311d0c4 39 ERR_raise(ERR_LIB_EC, EC_R_CURVE_DOES_NOT_SUPPORT_ECDSA);
9bf682f6
PS
40 return NULL;
41 }
42
43 return eckey->group->meth->ecdsa_sign_sig(dgst, dgst_len,
44 in_kinv, in_r, eckey);
45}
46
47int ossl_ecdsa_verify_sig(const unsigned char *dgst, int dgst_len,
48 const ECDSA_SIG *sig, EC_KEY *eckey)
49{
50 if (eckey->group->meth->ecdsa_verify_sig == NULL) {
9311d0c4 51 ERR_raise(ERR_LIB_EC, EC_R_CURVE_DOES_NOT_SUPPORT_ECDSA);
9bf682f6
PS
52 return 0;
53 }
54
55 return eckey->group->meth->ecdsa_verify_sig(dgst, dgst_len, sig, eckey);
56}
57
a200a817
DSH
58int ossl_ecdsa_sign(int type, const unsigned char *dgst, int dlen,
59 unsigned char *sig, unsigned int *siglen,
60 const BIGNUM *kinv, const BIGNUM *r, EC_KEY *eckey)
61{
62 ECDSA_SIG *s;
75e2c877 63
a200a817
DSH
64 s = ECDSA_do_sign_ex(dgst, dlen, kinv, r, eckey);
65 if (s == NULL) {
66 *siglen = 0;
67 return 0;
68 }
69 *siglen = i2d_ECDSA_SIG(s, &sig);
70 ECDSA_SIG_free(s);
71 return 1;
72}
73
8d6a75dc 74static int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in,
0f113f3e
MC
75 BIGNUM **kinvp, BIGNUM **rp,
76 const unsigned char *dgst, int dlen)
4d94ae00 77{
0f113f3e 78 BN_CTX *ctx = NULL;
be2e334f
DSH
79 BIGNUM *k = NULL, *r = NULL, *X = NULL;
80 const BIGNUM *order;
0f113f3e
MC
81 EC_POINT *tmp_point = NULL;
82 const EC_GROUP *group;
83 int ret = 0;
4a089bbd 84 int order_bits;
7408f675 85 const BIGNUM *priv_key;
9dd84053 86
0f113f3e 87 if (eckey == NULL || (group = EC_KEY_get0_group(eckey)) == NULL) {
9311d0c4 88 ERR_raise(ERR_LIB_EC, ERR_R_PASSED_NULL_PARAMETER);
0f113f3e
MC
89 return 0;
90 }
7408f675 91 if ((priv_key = EC_KEY_get0_private_key(eckey)) == NULL) {
9311d0c4 92 ERR_raise(ERR_LIB_EC, EC_R_MISSING_PRIVATE_KEY);
7408f675
DO
93 return 0;
94 }
a74333f9 95
4b0555ec 96 if (!EC_KEY_can_sign(eckey)) {
9311d0c4 97 ERR_raise(ERR_LIB_EC, EC_R_CURVE_DOES_NOT_SUPPORT_SIGNING);
4b0555ec
DSH
98 return 0;
99 }
100
fff7a0dc 101 if ((ctx = ctx_in) == NULL) {
a9612d6c 102 if ((ctx = BN_CTX_new_ex(eckey->libctx)) == NULL) {
9311d0c4 103 ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
0f113f3e
MC
104 return 0;
105 }
fff7a0dc 106 }
4d94ae00 107
bb315ca7 108 k = BN_secure_new(); /* this value is later returned in *kinvp */
0f113f3e 109 r = BN_new(); /* this value is later returned in *rp */
0f113f3e 110 X = BN_new();
be2e334f 111 if (k == NULL || r == NULL || X == NULL) {
9311d0c4 112 ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
0f113f3e
MC
113 goto err;
114 }
115 if ((tmp_point = EC_POINT_new(group)) == NULL) {
9311d0c4 116 ERR_raise(ERR_LIB_EC, ERR_R_EC_LIB);
0f113f3e
MC
117 goto err;
118 }
be2e334f 119 order = EC_GROUP_get0_order(group);
cac4fb58 120
4a089bbd
P
121 /* Preallocate space */
122 order_bits = BN_num_bits(order);
123 if (!BN_set_bit(k, order_bits)
124 || !BN_set_bit(r, order_bits)
125 || !BN_set_bit(X, order_bits))
126 goto err;
127
0f113f3e
MC
128 do {
129 /* get random k */
fff7a0dc 130 do {
0f113f3e 131 if (dgst != NULL) {
7408f675 132 if (!BN_generate_dsa_nonce(k, order, priv_key,
fff7a0dc 133 dgst, dlen, ctx)) {
9311d0c4 134 ERR_raise(ERR_LIB_EC, EC_R_RANDOM_NUMBER_GENERATION_FAILED);
0f113f3e
MC
135 goto err;
136 }
474e469b 137 } else {
a9612d6c 138 if (!BN_priv_rand_range_ex(k, order, ctx)) {
9311d0c4 139 ERR_raise(ERR_LIB_EC, EC_R_RANDOM_NUMBER_GENERATION_FAILED);
0f113f3e
MC
140 goto err;
141 }
142 }
fff7a0dc 143 } while (BN_is_zero(k));
4d94ae00 144
0f113f3e
MC
145 /* compute r the x-coordinate of generator * k */
146 if (!EC_POINT_mul(group, tmp_point, k, NULL, NULL, ctx)) {
9311d0c4 147 ERR_raise(ERR_LIB_EC, ERR_R_EC_LIB);
0f113f3e
MC
148 goto err;
149 }
9cc570d4
MC
150
151 if (!EC_POINT_get_affine_coordinates(group, tmp_point, X, NULL, ctx)) {
9311d0c4 152 ERR_raise(ERR_LIB_EC, ERR_R_EC_LIB);
9cc570d4 153 goto err;
0f113f3e 154 }
9cc570d4 155
0f113f3e 156 if (!BN_nnmod(r, X, order, ctx)) {
9311d0c4 157 ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
0f113f3e
MC
158 goto err;
159 }
fff7a0dc 160 } while (BN_is_zero(r));
4d94ae00 161
c11d372b 162 /* compute the inverse of k */
792546eb 163 if (!ec_group_do_inverse_ord(group, k, k, ctx)) {
9311d0c4 164 ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
c11d372b 165 goto err;
0f113f3e 166 }
f54be179 167
0f113f3e 168 /* clear old values if necessary */
23a1d5e9
RS
169 BN_clear_free(*rp);
170 BN_clear_free(*kinvp);
0f113f3e
MC
171 /* save the pre-computed values */
172 *rp = r;
173 *kinvp = k;
174 ret = 1;
175 err:
176 if (!ret) {
23a1d5e9
RS
177 BN_clear_free(k);
178 BN_clear_free(r);
0f113f3e 179 }
23a1d5e9 180 if (ctx != ctx_in)
0f113f3e 181 BN_CTX_free(ctx);
8fdc3734 182 EC_POINT_free(tmp_point);
23a1d5e9 183 BN_clear_free(X);
26a7d938 184 return ret;
4d94ae00
BM
185}
186
9bf682f6
PS
187int ecdsa_simple_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp,
188 BIGNUM **rp)
6a47db45
DSH
189{
190 return ecdsa_sign_setup(eckey, ctx_in, kinvp, rp, NULL, 0);
191}
192
9bf682f6
PS
193ECDSA_SIG *ecdsa_simple_sign_sig(const unsigned char *dgst, int dgst_len,
194 const BIGNUM *in_kinv, const BIGNUM *in_r,
195 EC_KEY *eckey)
4d94ae00 196{
0f113f3e 197 int ok = 0, i;
37132c97 198 BIGNUM *kinv = NULL, *s, *m = NULL;
be2e334f 199 const BIGNUM *order, *ckinv;
0f113f3e
MC
200 BN_CTX *ctx = NULL;
201 const EC_GROUP *group;
202 ECDSA_SIG *ret;
0f113f3e
MC
203 const BIGNUM *priv_key;
204
0f113f3e
MC
205 group = EC_KEY_get0_group(eckey);
206 priv_key = EC_KEY_get0_private_key(eckey);
14a7cfb3 207
7408f675 208 if (group == NULL) {
9311d0c4 209 ERR_raise(ERR_LIB_EC, ERR_R_PASSED_NULL_PARAMETER);
0f113f3e
MC
210 return NULL;
211 }
7408f675 212 if (priv_key == NULL) {
9311d0c4 213 ERR_raise(ERR_LIB_EC, EC_R_MISSING_PRIVATE_KEY);
7408f675
DO
214 return NULL;
215 }
4d94ae00 216
4b0555ec 217 if (!EC_KEY_can_sign(eckey)) {
9311d0c4 218 ERR_raise(ERR_LIB_EC, EC_R_CURVE_DOES_NOT_SUPPORT_SIGNING);
4b0555ec
DSH
219 return NULL;
220 }
221
0f113f3e 222 ret = ECDSA_SIG_new();
90945fa3 223 if (ret == NULL) {
9311d0c4 224 ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
0f113f3e
MC
225 return NULL;
226 }
8cc44d97
DSH
227 ret->r = BN_new();
228 ret->s = BN_new();
229 if (ret->r == NULL || ret->s == NULL) {
9311d0c4 230 ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
8cc44d97
DSH
231 goto err;
232 }
0f113f3e 233 s = ret->s;
c6700d27 234
a9612d6c 235 if ((ctx = BN_CTX_new_ex(eckey->libctx)) == NULL
37132c97 236 || (m = BN_new()) == NULL) {
9311d0c4 237 ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
0f113f3e
MC
238 goto err;
239 }
4d94ae00 240
be2e334f 241 order = EC_GROUP_get0_order(group);
0f113f3e
MC
242 i = BN_num_bits(order);
243 /*
244 * Need to truncate digest if it is too long: first truncate whole bytes.
245 */
246 if (8 * dgst_len > i)
247 dgst_len = (i + 7) / 8;
248 if (!BN_bin2bn(dgst, dgst_len, m)) {
9311d0c4 249 ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
0f113f3e
MC
250 goto err;
251 }
fff7a0dc 252 /* If still too long, truncate remaining bits with a shift */
0f113f3e 253 if ((8 * dgst_len > i) && !BN_rshift(m, m, 8 - (i & 0x7))) {
9311d0c4 254 ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
0f113f3e
MC
255 goto err;
256 }
257 do {
258 if (in_kinv == NULL || in_r == NULL) {
259 if (!ecdsa_sign_setup(eckey, ctx, &kinv, &ret->r, dgst, dgst_len)) {
9311d0c4 260 ERR_raise(ERR_LIB_EC, ERR_R_ECDSA_LIB);
0f113f3e
MC
261 goto err;
262 }
263 ckinv = kinv;
264 } else {
265 ckinv = in_kinv;
266 if (BN_copy(ret->r, in_r) == NULL) {
9311d0c4 267 ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
0f113f3e
MC
268 goto err;
269 }
270 }
4d94ae00 271
37132c97
AP
272 /*
273 * With only one multiplicant being in Montgomery domain
274 * multiplication yields real result without post-conversion.
275 * Also note that all operations but last are performed with
276 * zero-padded vectors. Last operation, BN_mod_mul_montgomery
277 * below, returns user-visible value with removed zero padding.
278 */
279 if (!bn_to_mont_fixed_top(s, ret->r, group->mont_data, ctx)
280 || !bn_mul_mont_fixed_top(s, s, priv_key, group->mont_data, ctx)) {
9311d0c4 281 ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
a3e9d5aa
MC
282 goto err;
283 }
37132c97 284 if (!bn_mod_add_fixed_top(s, s, m, order)) {
9311d0c4 285 ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
0f113f3e
MC
286 goto err;
287 }
37132c97
AP
288 /*
289 * |s| can still be larger than modulus, because |m| can be. In
290 * such case we count on Montgomery reduction to tie it up.
291 */
292 if (!bn_to_mont_fixed_top(s, s, group->mont_data, ctx)
293 || !BN_mod_mul_montgomery(s, s, ckinv, group->mont_data, ctx)) {
9311d0c4 294 ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
a3e9d5aa
MC
295 goto err;
296 }
37132c97 297
0f113f3e
MC
298 if (BN_is_zero(s)) {
299 /*
532b1183 300 * if kinv and r have been supplied by the caller, don't
0f113f3e
MC
301 * generate new kinv and r values
302 */
303 if (in_kinv != NULL && in_r != NULL) {
9311d0c4 304 ERR_raise(ERR_LIB_EC, EC_R_NEED_NEW_SETUP_VALUES);
0f113f3e
MC
305 goto err;
306 }
fff7a0dc 307 } else {
0f113f3e
MC
308 /* s != 0 => we have a valid signature */
309 break;
fff7a0dc
AP
310 }
311 } while (1);
4d94ae00 312
0f113f3e
MC
313 ok = 1;
314 err:
315 if (!ok) {
316 ECDSA_SIG_free(ret);
317 ret = NULL;
318 }
23a1d5e9 319 BN_CTX_free(ctx);
3fc7a9b9 320 BN_clear_free(m);
23a1d5e9 321 BN_clear_free(kinv);
0f113f3e 322 return ret;
4d94ae00
BM
323}
324
a200a817
DSH
325/*-
326 * returns
327 * 1: correct signature
328 * 0: incorrect signature
329 * -1: error
330 */
331int ossl_ecdsa_verify(int type, const unsigned char *dgst, int dgst_len,
332 const unsigned char *sigbuf, int sig_len, EC_KEY *eckey)
333{
334 ECDSA_SIG *s;
335 const unsigned char *p = sigbuf;
336 unsigned char *der = NULL;
337 int derlen = -1;
338 int ret = -1;
339
340 s = ECDSA_SIG_new();
341 if (s == NULL)
26a7d938 342 return ret;
a200a817
DSH
343 if (d2i_ECDSA_SIG(&s, &p, sig_len) == NULL)
344 goto err;
345 /* Ensure signature uses DER and doesn't have trailing garbage */
346 derlen = i2d_ECDSA_SIG(s, &der);
91e7bcc2 347 if (derlen != sig_len || memcmp(sigbuf, der, derlen) != 0)
a200a817
DSH
348 goto err;
349 ret = ECDSA_do_verify(dgst, dgst_len, s, eckey);
350 err:
cff7d199 351 OPENSSL_free(der);
a200a817 352 ECDSA_SIG_free(s);
26a7d938 353 return ret;
a200a817
DSH
354}
355
9bf682f6
PS
356int ecdsa_simple_verify_sig(const unsigned char *dgst, int dgst_len,
357 const ECDSA_SIG *sig, EC_KEY *eckey)
4d94ae00 358{
0f113f3e
MC
359 int ret = -1, i;
360 BN_CTX *ctx;
be2e334f
DSH
361 const BIGNUM *order;
362 BIGNUM *u1, *u2, *m, *X;
0f113f3e
MC
363 EC_POINT *point = NULL;
364 const EC_GROUP *group;
365 const EC_POINT *pub_key;
9dd84053 366
0f113f3e
MC
367 /* check input values */
368 if (eckey == NULL || (group = EC_KEY_get0_group(eckey)) == NULL ||
369 (pub_key = EC_KEY_get0_public_key(eckey)) == NULL || sig == NULL) {
9311d0c4 370 ERR_raise(ERR_LIB_EC, EC_R_MISSING_PARAMETERS);
0f113f3e
MC
371 return -1;
372 }
4d94ae00 373
4b0555ec 374 if (!EC_KEY_can_sign(eckey)) {
9311d0c4 375 ERR_raise(ERR_LIB_EC, EC_R_CURVE_DOES_NOT_SUPPORT_SIGNING);
4b0555ec
DSH
376 return -1;
377 }
378
a9612d6c 379 ctx = BN_CTX_new_ex(eckey->libctx);
90945fa3 380 if (ctx == NULL) {
9311d0c4 381 ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
0f113f3e
MC
382 return -1;
383 }
384 BN_CTX_start(ctx);
0f113f3e
MC
385 u1 = BN_CTX_get(ctx);
386 u2 = BN_CTX_get(ctx);
387 m = BN_CTX_get(ctx);
388 X = BN_CTX_get(ctx);
91e7bcc2 389 if (X == NULL) {
9311d0c4 390 ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
0f113f3e
MC
391 goto err;
392 }
c6700d27 393
be2e334f
DSH
394 order = EC_GROUP_get0_order(group);
395 if (order == NULL) {
9311d0c4 396 ERR_raise(ERR_LIB_EC, ERR_R_EC_LIB);
0f113f3e
MC
397 goto err;
398 }
4d94ae00 399
0f113f3e
MC
400 if (BN_is_zero(sig->r) || BN_is_negative(sig->r) ||
401 BN_ucmp(sig->r, order) >= 0 || BN_is_zero(sig->s) ||
402 BN_is_negative(sig->s) || BN_ucmp(sig->s, order) >= 0) {
9311d0c4 403 ERR_raise(ERR_LIB_EC, EC_R_BAD_SIGNATURE);
0f113f3e
MC
404 ret = 0; /* signature is invalid */
405 goto err;
406 }
407 /* calculate tmp1 = inv(S) mod order */
792546eb 408 if (!ec_group_do_inverse_ord(group, u2, sig->s, ctx)) {
9311d0c4 409 ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
c11d372b 410 goto err;
0f113f3e
MC
411 }
412 /* digest -> m */
413 i = BN_num_bits(order);
414 /*
415 * Need to truncate digest if it is too long: first truncate whole bytes.
416 */
417 if (8 * dgst_len > i)
418 dgst_len = (i + 7) / 8;
419 if (!BN_bin2bn(dgst, dgst_len, m)) {
9311d0c4 420 ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
0f113f3e
MC
421 goto err;
422 }
423 /* If still too long truncate remaining bits with a shift */
424 if ((8 * dgst_len > i) && !BN_rshift(m, m, 8 - (i & 0x7))) {
9311d0c4 425 ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
0f113f3e
MC
426 goto err;
427 }
428 /* u1 = m * tmp mod order */
429 if (!BN_mod_mul(u1, m, u2, order, ctx)) {
9311d0c4 430 ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
0f113f3e
MC
431 goto err;
432 }
433 /* u2 = r * w mod q */
434 if (!BN_mod_mul(u2, sig->r, u2, order, ctx)) {
9311d0c4 435 ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
0f113f3e
MC
436 goto err;
437 }
438
439 if ((point = EC_POINT_new(group)) == NULL) {
9311d0c4 440 ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
0f113f3e
MC
441 goto err;
442 }
443 if (!EC_POINT_mul(group, point, u1, pub_key, u2, ctx)) {
9311d0c4 444 ERR_raise(ERR_LIB_EC, ERR_R_EC_LIB);
0f113f3e
MC
445 goto err;
446 }
0f113f3e 447
9cc570d4 448 if (!EC_POINT_get_affine_coordinates(group, point, X, NULL, ctx)) {
9311d0c4 449 ERR_raise(ERR_LIB_EC, ERR_R_EC_LIB);
9cc570d4 450 goto err;
0f113f3e 451 }
9cc570d4 452
0f113f3e 453 if (!BN_nnmod(u1, X, order, ctx)) {
9311d0c4 454 ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
0f113f3e
MC
455 goto err;
456 }
457 /* if the signature is correct u1 is equal to sig->r */
458 ret = (BN_ucmp(u1, sig->r) == 0);
459 err:
460 BN_CTX_end(ctx);
461 BN_CTX_free(ctx);
8fdc3734 462 EC_POINT_free(point);
0f113f3e 463 return ret;
4d94ae00 464}