1 /**********************************************************************
3 * Copyright (c) 2005-2006 Cryptocom LTD *
4 * This file is distributed under the same license as OpenSSL *
6 * Implementation of GOST R 34.10-2001 *
7 * Requires OpenSSL 0.9.9 for compilation *
8 **********************************************************************/
10 #include "gost_params.h"
12 #include <openssl/rand.h>
13 #include <openssl/ecdsa.h>
14 #include <openssl/err.h>
15 #include "e_gost_err.h"
18 void dump_signature(const char *message, const unsigned char *buffer,
20 void dump_dsa_sig(const char *message, DSA_SIG *sig);
23 # define dump_signature(a,b,c)
24 # define dump_dsa_sig(a,b)
28 * Fills EC_KEY structure hidden in the app_data field of DSA structure
29 * with parameter information, extracted from parameter array in
32 * Also fils DSA->q field with copy of EC_GROUP order field to make
33 * DSA_size function work
35 int fill_GOST2001_params(EC_KEY *eckey, int nid)
37 R3410_2001_params *params = R3410_2001_paramset;
39 BIGNUM *p = NULL, *q = NULL, *a = NULL, *b = NULL, *x = NULL, *y = NULL;
41 BN_CTX *ctx = BN_CTX_new();
45 GOSTerr(GOST_F_FILL_GOST2001_PARAMS, ERR_R_MALLOC_FAILURE);
56 if (!p || !a || !b || !x || !y || !q) {
57 GOSTerr(GOST_F_FILL_GOST2001_PARAMS, ERR_R_MALLOC_FAILURE);
60 while (params->nid != NID_undef && params->nid != nid)
62 if (params->nid == NID_undef) {
63 GOSTerr(GOST_F_FILL_GOST2001_PARAMS,
64 GOST_R_UNSUPPORTED_PARAMETER_SET);
67 if (!BN_hex2bn(&p, params->p)
68 || !BN_hex2bn(&a, params->a)
69 || !BN_hex2bn(&b, params->b)) {
70 GOSTerr(GOST_F_FILL_GOST2001_PARAMS,
71 ERR_R_INTERNAL_ERROR);
75 grp = EC_GROUP_new_curve_GFp(p, a, b, ctx);
77 GOSTerr(GOST_F_FILL_GOST2001_PARAMS, ERR_R_MALLOC_FAILURE);
81 P = EC_POINT_new(grp);
83 GOSTerr(GOST_F_FILL_GOST2001_PARAMS, ERR_R_MALLOC_FAILURE);
87 if (!BN_hex2bn(&x, params->x)
88 || !BN_hex2bn(&y, params->y)
89 || !EC_POINT_set_affine_coordinates_GFp(grp, P, x, y, ctx)
90 || !BN_hex2bn(&q, params->q)) {
91 GOSTerr(GOST_F_FILL_GOST2001_PARAMS, ERR_R_INTERNAL_ERROR);
95 fprintf(stderr, "Set params index %d oid %s\nq=",
96 (params - R3410_2001_paramset), OBJ_nid2sn(params->nid));
97 BN_print_fp(stderr, q);
98 fprintf(stderr, "\n");
101 if (!EC_GROUP_set_generator(grp, P, q, NULL)) {
102 GOSTerr(GOST_F_FILL_GOST2001_PARAMS, ERR_R_INTERNAL_ERROR);
105 EC_GROUP_set_curve_name(grp, params->nid);
106 if (!EC_KEY_set_group(eckey, grp)) {
107 GOSTerr(GOST_F_FILL_GOST2001_PARAMS, ERR_R_INTERNAL_ERROR);
121 * Computes gost2001 signature as DSA_SIG structure
125 DSA_SIG *gost2001_do_sign(const unsigned char *dgst, int dlen, EC_KEY *eckey)
127 DSA_SIG *newsig = NULL, *ret = NULL;
128 BIGNUM *md = hashsum2bn(dgst);
129 BIGNUM *order = NULL;
130 const EC_GROUP *group;
131 const BIGNUM *priv_key;
132 BIGNUM *r = NULL, *s = NULL, *X = NULL, *tmp = NULL, *tmp2 = NULL, *k =
135 BN_CTX *ctx = BN_CTX_new();
137 GOSTerr(GOST_F_GOST2001_DO_SIGN, ERR_R_MALLOC_FAILURE);
141 OPENSSL_assert(dlen == 32);
142 newsig = DSA_SIG_new();
144 GOSTerr(GOST_F_GOST2001_DO_SIGN, ERR_R_MALLOC_FAILURE);
147 group = EC_KEY_get0_group(eckey);
149 GOSTerr(GOST_F_GOST2001_DO_SIGN, ERR_R_INTERNAL_ERROR);
152 order = BN_CTX_get(ctx);
153 if (!order || !EC_GROUP_get_order(group, order, ctx)) {
154 GOSTerr(GOST_F_GOST2001_DO_SIGN, ERR_R_INTERNAL_ERROR);
157 priv_key = EC_KEY_get0_private_key(eckey);
159 GOSTerr(GOST_F_GOST2001_DO_SIGN, ERR_R_INTERNAL_ERROR);
163 if (!e || !BN_mod(e, md, order, ctx)) {
164 GOSTerr(GOST_F_GOST2001_DO_SIGN, ERR_R_INTERNAL_ERROR);
168 fprintf(stderr, "digest as bignum=");
169 BN_print_fp(stderr, md);
170 fprintf(stderr, "\ndigest mod q=");
171 BN_print_fp(stderr, e);
172 fprintf(stderr, "\n");
178 C = EC_POINT_new(group);
180 GOSTerr(GOST_F_GOST2001_DO_SIGN, ERR_R_MALLOC_FAILURE);
185 if (!BN_rand_range(k, order)) {
186 GOSTerr(GOST_F_GOST2001_DO_SIGN,
187 GOST_R_RANDOM_NUMBER_GENERATOR_FAILED);
190 if (!EC_POINT_mul(group, C, k, NULL, NULL, ctx)) {
191 GOSTerr(GOST_F_GOST2001_DO_SIGN, ERR_R_EC_LIB);
199 GOSTerr(GOST_F_GOST2001_DO_SIGN, ERR_R_MALLOC_FAILURE);
202 if (!EC_POINT_get_affine_coordinates_GFp(group, C, X, NULL, ctx)) {
203 GOSTerr(GOST_F_GOST2001_DO_SIGN, ERR_R_EC_LIB);
207 if (!BN_nnmod(r, X, order, ctx)) {
208 GOSTerr(GOST_F_GOST2001_DO_SIGN, ERR_R_INTERNAL_ERROR);
212 while (BN_is_zero(r));
213 /* s = (r*priv_key+k*e) mod order */
215 tmp = BN_CTX_get(ctx);
217 tmp2 = BN_CTX_get(ctx);
220 if (!tmp || !tmp2 || !s) {
221 GOSTerr(GOST_F_GOST2001_DO_SIGN, ERR_R_MALLOC_FAILURE);
225 if (!BN_mod_mul(tmp, priv_key, r, order, ctx)
226 || !BN_mod_mul(tmp2, k, e, order, ctx)
227 || !BN_mod_add(s, tmp, tmp2, order, ctx)) {
228 GOSTerr(GOST_F_GOST2001_DO_SIGN, ERR_R_INTERNAL_ERROR);
232 while (BN_is_zero(s));
234 newsig->s = BN_dup(s);
235 newsig->r = BN_dup(r);
236 if (!newsig->s || !newsig->r) {
237 GOSTerr(GOST_F_GOST2001_DO_SIGN, ERR_R_MALLOC_FAILURE);
249 DSA_SIG_free(newsig);
254 * Verifies gost 2001 signature
257 int gost2001_do_verify(const unsigned char *dgst, int dgst_len,
258 DSA_SIG *sig, EC_KEY *ec)
260 BN_CTX *ctx = BN_CTX_new();
261 const EC_GROUP *group = EC_KEY_get0_group(ec);
263 BIGNUM *md = NULL, *e = NULL, *R = NULL, *v = NULL, *z1 = NULL, *z2 =
265 BIGNUM *X = NULL, *tmp = NULL;
267 const EC_POINT *pub_key = NULL;
270 if (!ctx || !group) {
271 GOSTerr(GOST_F_GOST2001_DO_VERIFY, ERR_R_INTERNAL_ERROR);
276 order = BN_CTX_get(ctx);
278 z1 = BN_CTX_get(ctx);
279 z2 = BN_CTX_get(ctx);
280 tmp = BN_CTX_get(ctx);
284 if (!order || !e || !z1 || !z2 || !tmp || !X || !R || !v) {
285 GOSTerr(GOST_F_GOST2001_DO_VERIFY, ERR_R_MALLOC_FAILURE);
289 pub_key = EC_KEY_get0_public_key(ec);
290 if (!pub_key || !EC_GROUP_get_order(group, order, ctx)) {
291 GOSTerr(GOST_F_GOST2001_DO_VERIFY, ERR_R_INTERNAL_ERROR);
295 if (BN_is_zero(sig->s) || BN_is_zero(sig->r) ||
296 (BN_cmp(sig->s, order) >= 1) || (BN_cmp(sig->r, order) >= 1)) {
297 GOSTerr(GOST_F_GOST2001_DO_VERIFY,
298 GOST_R_SIGNATURE_PARTS_GREATER_THAN_Q);
302 md = hashsum2bn(dgst);
304 if (!md || !BN_mod(e, md, order, ctx)) {
305 GOSTerr(GOST_F_GOST2001_DO_VERIFY, ERR_R_INTERNAL_ERROR);
309 fprintf(stderr, "digest as bignum: ");
310 BN_print_fp(stderr, md);
311 fprintf(stderr, "\ndigest mod q: ");
312 BN_print_fp(stderr, e);
314 if (BN_is_zero(e) && !BN_one(e)) {
315 GOSTerr(GOST_F_GOST2001_DO_VERIFY, ERR_R_INTERNAL_ERROR);
318 v = BN_mod_inverse(v, e, order, ctx);
320 || !BN_mod_mul(z1, sig->s, v, order, ctx)
321 || !BN_sub(tmp, order, sig->r)
322 || !BN_mod_mul(z2, tmp, v, order, ctx)) {
323 GOSTerr(GOST_F_GOST2001_DO_VERIFY, ERR_R_INTERNAL_ERROR);
327 fprintf(stderr, "\nInverted digest value: ");
328 BN_print_fp(stderr, v);
329 fprintf(stderr, "\nz1: ");
330 BN_print_fp(stderr, z1);
331 fprintf(stderr, "\nz2: ");
332 BN_print_fp(stderr, z2);
334 C = EC_POINT_new(group);
336 GOSTerr(GOST_F_GOST2001_DO_VERIFY, ERR_R_MALLOC_FAILURE);
339 if (!EC_POINT_mul(group, C, z1, pub_key, z2, ctx)) {
340 GOSTerr(GOST_F_GOST2001_DO_VERIFY, ERR_R_EC_LIB);
343 if (!EC_POINT_get_affine_coordinates_GFp(group, C, X, NULL, ctx)) {
344 GOSTerr(GOST_F_GOST2001_DO_VERIFY, ERR_R_EC_LIB);
347 if (!BN_mod(R, X, order, ctx)) {
348 GOSTerr(GOST_F_GOST2001_DO_VERIFY, ERR_R_INTERNAL_ERROR);
352 fprintf(stderr, "\nX=");
353 BN_print_fp(stderr, X);
354 fprintf(stderr, "\nX mod q=");
355 BN_print_fp(stderr, R);
356 fprintf(stderr, "\n");
358 if (BN_cmp(R, sig->r) != 0) {
359 GOSTerr(GOST_F_GOST2001_DO_VERIFY, GOST_R_SIGNATURE_MISMATCH);
373 * Computes GOST R 34.10-2001 public key
377 int gost2001_compute_public(EC_KEY *ec)
379 const EC_GROUP *group = EC_KEY_get0_group(ec);
380 EC_POINT *pub_key = NULL;
381 const BIGNUM *priv_key = NULL;
386 GOSTerr(GOST_F_GOST2001_COMPUTE_PUBLIC,
387 GOST_R_KEY_IS_NOT_INITIALIZED);
392 GOSTerr(GOST_F_GOST2001_COMPUTE_PUBLIC, ERR_R_MALLOC_FAILURE);
396 if (!(priv_key = EC_KEY_get0_private_key(ec))) {
397 GOSTerr(GOST_F_GOST2001_COMPUTE_PUBLIC, ERR_R_EC_LIB);
401 pub_key = EC_POINT_new(group);
403 GOSTerr(GOST_F_GOST2001_COMPUTE_PUBLIC, ERR_R_MALLOC_FAILURE);
406 if (!EC_POINT_mul(group, pub_key, priv_key, NULL, NULL, ctx)) {
407 GOSTerr(GOST_F_GOST2001_COMPUTE_PUBLIC, ERR_R_EC_LIB);
410 if (!EC_KEY_set_public_key(ec, pub_key)) {
411 GOSTerr(GOST_F_GOST2001_COMPUTE_PUBLIC, ERR_R_EC_LIB);
416 EC_POINT_free(pub_key);
425 * Generates GOST R 34.10-2001 keypair
429 int gost2001_keygen(EC_KEY *ec)
431 BIGNUM *order = BN_new(), *d = BN_new();
432 const EC_GROUP *group = EC_KEY_get0_group(ec);
434 if (!group || !EC_GROUP_get_order(group, order, NULL)) {
435 GOSTerr(GOST_F_GOST2001_KEYGEN, ERR_R_INTERNAL_ERROR);
442 if (!BN_rand_range(d, order)) {
443 GOSTerr(GOST_F_GOST2001_KEYGEN,
444 GOST_R_RANDOM_NUMBER_GENERATOR_FAILED);
450 while (BN_is_zero(d));
452 if (!EC_KEY_set_private_key(ec, d)) {
453 GOSTerr(GOST_F_GOST2001_KEYGEN, ERR_R_INTERNAL_ERROR);
460 return gost2001_compute_public(ec);