VirtualBox

source: vbox/trunk/src/libs/openssl-3.0.7/crypto/sm2/sm2_sign.c@ 98929

Last change on this file since 98929 was 94082, checked in by vboxsync, 3 years ago

libs/openssl-3.0.1: started applying and adjusting our OpenSSL changes to 3.0.1. bugref:10128
File size: 14.0 KB
Line 
1/*
2 * Copyright 2017-2021 The OpenSSL Project Authors. All Rights Reserved.
3 * Copyright 2017 Ribose Inc. All Rights Reserved.
4 * Ported from Ribose contributions from Botan.
5 *
6 * Licensed under the Apache License 2.0 (the "License"). You may not use
7 * this file except in compliance with the License. You can obtain a copy
8 * in the file LICENSE in the source distribution or at
9 * https://www.openssl.org/source/license.html
10 */
11
12#include "internal/deprecated.h"
13
14#include "crypto/sm2.h"
15#include "crypto/sm2err.h"
16#include "crypto/ec.h" /* ossl_ec_group_do_inverse_ord() */
17#include "internal/numbers.h"
18#include <openssl/err.h>
19#include <openssl/evp.h>
20#include <openssl/err.h>
21#include <openssl/bn.h>
22#include <string.h>
23
24int ossl_sm2_compute_z_digest(uint8_t *out,
25 const EVP_MD *digest,
26 const uint8_t *id,
27 const size_t id_len,
28 const EC_KEY *key)
29{
30 int rc = 0;
31 const EC_GROUP *group = EC_KEY_get0_group(key);
32 BN_CTX *ctx = NULL;
33 EVP_MD_CTX *hash = NULL;
34 BIGNUM *p = NULL;
35 BIGNUM *a = NULL;
36 BIGNUM *b = NULL;
37 BIGNUM *xG = NULL;
38 BIGNUM *yG = NULL;
39 BIGNUM *xA = NULL;
40 BIGNUM *yA = NULL;
41 int p_bytes = 0;
42 uint8_t *buf = NULL;
43 uint16_t entl = 0;
44 uint8_t e_byte = 0;
45
46 hash = EVP_MD_CTX_new();
47 ctx = BN_CTX_new_ex(ossl_ec_key_get_libctx(key));
48 if (hash == NULL || ctx == NULL) {
49 ERR_raise(ERR_LIB_SM2, ERR_R_MALLOC_FAILURE);
50 goto done;
51 }
52
53 p = BN_CTX_get(ctx);
54 a = BN_CTX_get(ctx);
55 b = BN_CTX_get(ctx);
56 xG = BN_CTX_get(ctx);
57 yG = BN_CTX_get(ctx);
58 xA = BN_CTX_get(ctx);
59 yA = BN_CTX_get(ctx);
60
61 if (yA == NULL) {
62 ERR_raise(ERR_LIB_SM2, ERR_R_MALLOC_FAILURE);
63 goto done;
64 }
65
66 if (!EVP_DigestInit(hash, digest)) {
67 ERR_raise(ERR_LIB_SM2, ERR_R_EVP_LIB);
68 goto done;
69 }
70
71 /* Z = h(ENTL || ID || a || b || xG || yG || xA || yA) */
72
73 if (id_len >= (UINT16_MAX / 8)) {
74 /* too large */
75 ERR_raise(ERR_LIB_SM2, SM2_R_ID_TOO_LARGE);
76 goto done;
77 }
78
79 entl = (uint16_t)(8 * id_len);
80
81 e_byte = entl >> 8;
82 if (!EVP_DigestUpdate(hash, &e_byte, 1)) {
83 ERR_raise(ERR_LIB_SM2, ERR_R_EVP_LIB);
84 goto done;
85 }
86 e_byte = entl & 0xFF;
87 if (!EVP_DigestUpdate(hash, &e_byte, 1)) {
88 ERR_raise(ERR_LIB_SM2, ERR_R_EVP_LIB);
89 goto done;
90 }
91
92 if (id_len > 0 && !EVP_DigestUpdate(hash, id, id_len)) {
93 ERR_raise(ERR_LIB_SM2, ERR_R_EVP_LIB);
94 goto done;
95 }
96
97 if (!EC_GROUP_get_curve(group, p, a, b, ctx)) {
98 ERR_raise(ERR_LIB_SM2, ERR_R_EC_LIB);
99 goto done;
100 }
101
102 p_bytes = BN_num_bytes(p);
103 buf = OPENSSL_zalloc(p_bytes);
104 if (buf == NULL) {
105 ERR_raise(ERR_LIB_SM2, ERR_R_MALLOC_FAILURE);
106 goto done;
107 }
108
109 if (BN_bn2binpad(a, buf, p_bytes) < 0
110 || !EVP_DigestUpdate(hash, buf, p_bytes)
111 || BN_bn2binpad(b, buf, p_bytes) < 0
112 || !EVP_DigestUpdate(hash, buf, p_bytes)
113 || !EC_POINT_get_affine_coordinates(group,
114 EC_GROUP_get0_generator(group),
115 xG, yG, ctx)
116 || BN_bn2binpad(xG, buf, p_bytes) < 0
117 || !EVP_DigestUpdate(hash, buf, p_bytes)
118 || BN_bn2binpad(yG, buf, p_bytes) < 0
119 || !EVP_DigestUpdate(hash, buf, p_bytes)
120 || !EC_POINT_get_affine_coordinates(group,
121 EC_KEY_get0_public_key(key),
122 xA, yA, ctx)
123 || BN_bn2binpad(xA, buf, p_bytes) < 0
124 || !EVP_DigestUpdate(hash, buf, p_bytes)
125 || BN_bn2binpad(yA, buf, p_bytes) < 0
126 || !EVP_DigestUpdate(hash, buf, p_bytes)
127 || !EVP_DigestFinal(hash, out, NULL)) {
128 ERR_raise(ERR_LIB_SM2, ERR_R_INTERNAL_ERROR);
129 goto done;
130 }
131
132 rc = 1;
133
134 done:
135 OPENSSL_free(buf);
136 BN_CTX_free(ctx);
137 EVP_MD_CTX_free(hash);
138 return rc;
139}
140
141static BIGNUM *sm2_compute_msg_hash(const EVP_MD *digest,
142 const EC_KEY *key,
143 const uint8_t *id,
144 const size_t id_len,
145 const uint8_t *msg, size_t msg_len)
146{
147 EVP_MD_CTX *hash = EVP_MD_CTX_new();
148 const int md_size = EVP_MD_get_size(digest);
149 uint8_t *z = NULL;
150 BIGNUM *e = NULL;
151 EVP_MD *fetched_digest = NULL;
152 OSSL_LIB_CTX *libctx = ossl_ec_key_get_libctx(key);
153 const char *propq = ossl_ec_key_get0_propq(key);
154
155 if (md_size < 0) {
156 ERR_raise(ERR_LIB_SM2, SM2_R_INVALID_DIGEST);
157 goto done;
158 }
159
160 z = OPENSSL_zalloc(md_size);
161 if (hash == NULL || z == NULL) {
162 ERR_raise(ERR_LIB_SM2, ERR_R_MALLOC_FAILURE);
163 goto done;
164 }
165
166 fetched_digest = EVP_MD_fetch(libctx, EVP_MD_get0_name(digest), propq);
167 if (fetched_digest == NULL) {
168 ERR_raise(ERR_LIB_SM2, ERR_R_INTERNAL_ERROR);
169 goto done;
170 }
171
172 if (!ossl_sm2_compute_z_digest(z, fetched_digest, id, id_len, key)) {
173 /* SM2err already called */
174 goto done;
175 }
176
177 if (!EVP_DigestInit(hash, fetched_digest)
178 || !EVP_DigestUpdate(hash, z, md_size)
179 || !EVP_DigestUpdate(hash, msg, msg_len)
180 /* reuse z buffer to hold H(Z || M) */
181 || !EVP_DigestFinal(hash, z, NULL)) {
182 ERR_raise(ERR_LIB_SM2, ERR_R_EVP_LIB);
183 goto done;
184 }
185
186 e = BN_bin2bn(z, md_size, NULL);
187 if (e == NULL)
188 ERR_raise(ERR_LIB_SM2, ERR_R_INTERNAL_ERROR);
189
190 done:
191 EVP_MD_free(fetched_digest);
192 OPENSSL_free(z);
193 EVP_MD_CTX_free(hash);
194 return e;
195}
196
197static ECDSA_SIG *sm2_sig_gen(const EC_KEY *key, const BIGNUM *e)
198{
199 const BIGNUM *dA = EC_KEY_get0_private_key(key);
200 const EC_GROUP *group = EC_KEY_get0_group(key);
201 const BIGNUM *order = EC_GROUP_get0_order(group);
202 ECDSA_SIG *sig = NULL;
203 EC_POINT *kG = NULL;
204 BN_CTX *ctx = NULL;
205 BIGNUM *k = NULL;
206 BIGNUM *rk = NULL;
207 BIGNUM *r = NULL;
208 BIGNUM *s = NULL;
209 BIGNUM *x1 = NULL;
210 BIGNUM *tmp = NULL;
211 OSSL_LIB_CTX *libctx = ossl_ec_key_get_libctx(key);
212
213 kG = EC_POINT_new(group);
214 ctx = BN_CTX_new_ex(libctx);
215 if (kG == NULL || ctx == NULL) {
216 ERR_raise(ERR_LIB_SM2, ERR_R_MALLOC_FAILURE);
217 goto done;
218 }
219
220 BN_CTX_start(ctx);
221 k = BN_CTX_get(ctx);
222 rk = BN_CTX_get(ctx);
223 x1 = BN_CTX_get(ctx);
224 tmp = BN_CTX_get(ctx);
225 if (tmp == NULL) {
226 ERR_raise(ERR_LIB_SM2, ERR_R_MALLOC_FAILURE);
227 goto done;
228 }
229
230 /*
231 * These values are returned and so should not be allocated out of the
232 * context
233 */
234 r = BN_new();
235 s = BN_new();
236
237 if (r == NULL || s == NULL) {
238 ERR_raise(ERR_LIB_SM2, ERR_R_MALLOC_FAILURE);
239 goto done;
240 }
241
242 /*
243 * A3: Generate a random number k in [1,n-1] using random number generators;
244 * A4: Compute (x1,y1)=[k]G, and convert the type of data x1 to be integer
245 * as specified in clause 4.2.8 of GM/T 0003.1-2012;
246 * A5: Compute r=(e+x1) mod n. If r=0 or r+k=n, then go to A3;
247 * A6: Compute s=(1/(1+dA)*(k-r*dA)) mod n. If s=0, then go to A3;
248 * A7: Convert the type of data (r,s) to be bit strings according to the details
249 * in clause 4.2.2 of GM/T 0003.1-2012. Then the signature of message M is (r,s).
250 */
251 for (;;) {
252 if (!BN_priv_rand_range_ex(k, order, 0, ctx)) {
253 ERR_raise(ERR_LIB_SM2, ERR_R_INTERNAL_ERROR);
254 goto done;
255 }
256
257 if (!EC_POINT_mul(group, kG, k, NULL, NULL, ctx)
258 || !EC_POINT_get_affine_coordinates(group, kG, x1, NULL,
259 ctx)
260 || !BN_mod_add(r, e, x1, order, ctx)) {
261 ERR_raise(ERR_LIB_SM2, ERR_R_INTERNAL_ERROR);
262 goto done;
263 }
264
265 /* try again if r == 0 or r+k == n */
266 if (BN_is_zero(r))
267 continue;
268
269 if (!BN_add(rk, r, k)) {
270 ERR_raise(ERR_LIB_SM2, ERR_R_INTERNAL_ERROR);
271 goto done;
272 }
273
274 if (BN_cmp(rk, order) == 0)
275 continue;
276
277 if (!BN_add(s, dA, BN_value_one())
278 || !ossl_ec_group_do_inverse_ord(group, s, s, ctx)
279 || !BN_mod_mul(tmp, dA, r, order, ctx)
280 || !BN_sub(tmp, k, tmp)
281 || !BN_mod_mul(s, s, tmp, order, ctx)) {
282 ERR_raise(ERR_LIB_SM2, ERR_R_BN_LIB);
283 goto done;
284 }
285
286 /* try again if s == 0 */
287 if (BN_is_zero(s))
288 continue;
289
290 sig = ECDSA_SIG_new();
291 if (sig == NULL) {
292 ERR_raise(ERR_LIB_SM2, ERR_R_MALLOC_FAILURE);
293 goto done;
294 }
295
296 /* takes ownership of r and s */
297 ECDSA_SIG_set0(sig, r, s);
298 break;
299 }
300
301 done:
302 if (sig == NULL) {
303 BN_free(r);
304 BN_free(s);
305 }
306
307 BN_CTX_free(ctx);
308 EC_POINT_free(kG);
309 return sig;
310}
311
312static int sm2_sig_verify(const EC_KEY *key, const ECDSA_SIG *sig,
313 const BIGNUM *e)
314{
315 int ret = 0;
316 const EC_GROUP *group = EC_KEY_get0_group(key);
317 const BIGNUM *order = EC_GROUP_get0_order(group);
318 BN_CTX *ctx = NULL;
319 EC_POINT *pt = NULL;
320 BIGNUM *t = NULL;
321 BIGNUM *x1 = NULL;
322 const BIGNUM *r = NULL;
323 const BIGNUM *s = NULL;
324 OSSL_LIB_CTX *libctx = ossl_ec_key_get_libctx(key);
325
326 ctx = BN_CTX_new_ex(libctx);
327 pt = EC_POINT_new(group);
328 if (ctx == NULL || pt == NULL) {
329 ERR_raise(ERR_LIB_SM2, ERR_R_MALLOC_FAILURE);
330 goto done;
331 }
332
333 BN_CTX_start(ctx);
334 t = BN_CTX_get(ctx);
335 x1 = BN_CTX_get(ctx);
336 if (x1 == NULL) {
337 ERR_raise(ERR_LIB_SM2, ERR_R_MALLOC_FAILURE);
338 goto done;
339 }
340
341 /*
342 * B1: verify whether r' in [1,n-1], verification failed if not
343 * B2: verify whether s' in [1,n-1], verification failed if not
344 * B3: set M'~=ZA || M'
345 * B4: calculate e'=Hv(M'~)
346 * B5: calculate t = (r' + s') modn, verification failed if t=0
347 * B6: calculate the point (x1', y1')=[s']G + [t]PA
348 * B7: calculate R=(e'+x1') modn, verification pass if yes, otherwise failed
349 */
350
351 ECDSA_SIG_get0(sig, &r, &s);
352
353 if (BN_cmp(r, BN_value_one()) < 0
354 || BN_cmp(s, BN_value_one()) < 0
355 || BN_cmp(order, r) <= 0
356 || BN_cmp(order, s) <= 0) {
357 ERR_raise(ERR_LIB_SM2, SM2_R_BAD_SIGNATURE);
358 goto done;
359 }
360
361 if (!BN_mod_add(t, r, s, order, ctx)) {
362 ERR_raise(ERR_LIB_SM2, ERR_R_BN_LIB);
363 goto done;
364 }
365
366 if (BN_is_zero(t)) {
367 ERR_raise(ERR_LIB_SM2, SM2_R_BAD_SIGNATURE);
368 goto done;
369 }
370
371 if (!EC_POINT_mul(group, pt, s, EC_KEY_get0_public_key(key), t, ctx)
372 || !EC_POINT_get_affine_coordinates(group, pt, x1, NULL, ctx)) {
373 ERR_raise(ERR_LIB_SM2, ERR_R_EC_LIB);
374 goto done;
375 }
376
377 if (!BN_mod_add(t, e, x1, order, ctx)) {
378 ERR_raise(ERR_LIB_SM2, ERR_R_BN_LIB);
379 goto done;
380 }
381
382 if (BN_cmp(r, t) == 0)
383 ret = 1;
384
385 done:
386 EC_POINT_free(pt);
387 BN_CTX_free(ctx);
388 return ret;
389}
390
391ECDSA_SIG *ossl_sm2_do_sign(const EC_KEY *key,
392 const EVP_MD *digest,
393 const uint8_t *id,
394 const size_t id_len,
395 const uint8_t *msg, size_t msg_len)
396{
397 BIGNUM *e = NULL;
398 ECDSA_SIG *sig = NULL;
399
400 e = sm2_compute_msg_hash(digest, key, id, id_len, msg, msg_len);
401 if (e == NULL) {
402 /* SM2err already called */
403 goto done;
404 }
405
406 sig = sm2_sig_gen(key, e);
407
408 done:
409 BN_free(e);
410 return sig;
411}
412
413int ossl_sm2_do_verify(const EC_KEY *key,
414 const EVP_MD *digest,
415 const ECDSA_SIG *sig,
416 const uint8_t *id,
417 const size_t id_len,
418 const uint8_t *msg, size_t msg_len)
419{
420 BIGNUM *e = NULL;
421 int ret = 0;
422
423 e = sm2_compute_msg_hash(digest, key, id, id_len, msg, msg_len);
424 if (e == NULL) {
425 /* SM2err already called */
426 goto done;
427 }
428
429 ret = sm2_sig_verify(key, sig, e);
430
431 done:
432 BN_free(e);
433 return ret;
434}
435
436int ossl_sm2_internal_sign(const unsigned char *dgst, int dgstlen,
437 unsigned char *sig, unsigned int *siglen,
438 EC_KEY *eckey)
439{
440 BIGNUM *e = NULL;
441 ECDSA_SIG *s = NULL;
442 int sigleni;
443 int ret = -1;
444
445 e = BN_bin2bn(dgst, dgstlen, NULL);
446 if (e == NULL) {
447 ERR_raise(ERR_LIB_SM2, ERR_R_BN_LIB);
448 goto done;
449 }
450
451 s = sm2_sig_gen(eckey, e);
452 if (s == NULL) {
453 ERR_raise(ERR_LIB_SM2, ERR_R_INTERNAL_ERROR);
454 goto done;
455 }
456
457 sigleni = i2d_ECDSA_SIG(s, &sig);
458 if (sigleni < 0) {
459 ERR_raise(ERR_LIB_SM2, ERR_R_INTERNAL_ERROR);
460 goto done;
461 }
462 *siglen = (unsigned int)sigleni;
463
464 ret = 1;
465
466 done:
467 ECDSA_SIG_free(s);
468 BN_free(e);
469 return ret;
470}
471
472int ossl_sm2_internal_verify(const unsigned char *dgst, int dgstlen,
473 const unsigned char *sig, int sig_len,
474 EC_KEY *eckey)
475{
476 ECDSA_SIG *s = NULL;
477 BIGNUM *e = NULL;
478 const unsigned char *p = sig;
479 unsigned char *der = NULL;
480 int derlen = -1;
481 int ret = -1;
482
483 s = ECDSA_SIG_new();
484 if (s == NULL) {
485 ERR_raise(ERR_LIB_SM2, ERR_R_MALLOC_FAILURE);
486 goto done;
487 }
488 if (d2i_ECDSA_SIG(&s, &p, sig_len) == NULL) {
489 ERR_raise(ERR_LIB_SM2, SM2_R_INVALID_ENCODING);
490 goto done;
491 }
492 /* Ensure signature uses DER and doesn't have trailing garbage */
493 derlen = i2d_ECDSA_SIG(s, &der);
494 if (derlen != sig_len || memcmp(sig, der, derlen) != 0) {
495 ERR_raise(ERR_LIB_SM2, SM2_R_INVALID_ENCODING);
496 goto done;
497 }
498
499 e = BN_bin2bn(dgst, dgstlen, NULL);
500 if (e == NULL) {
501 ERR_raise(ERR_LIB_SM2, ERR_R_BN_LIB);
502 goto done;
503 }
504
505 ret = sm2_sig_verify(eckey, s, e);
506
507 done:
508 OPENSSL_free(der);
509 BN_free(e);
510 ECDSA_SIG_free(s);
511 return ret;
512}
Note: See TracBrowser for help on using the repository browser.

© 2024 Oracle Support Privacy / Do Not Sell My Info Terms of Use Trademark Policy Automated Access Etiquette