--- /dev/null
+/**********************************************************************
+ * gost_ec_sign.c *
+ * Copyright (c) 2005-2013 Cryptocom LTD *
+ * This file is distributed under the same license as OpenSSL *
+ * *
+ * Implementation of GOST R 34.10-2001 *
+ * Requires OpenSSL 1.0.0+ for compilation *
+ **********************************************************************/
+#include "gost_lcl.h"
+#include "gost_params.h"
+#include <string.h>
+#include <openssl/rand.h>
+#include <openssl/ecdsa.h>
+#include <openssl/err.h>
+#include "e_gost_err.h"
+#ifdef DEBUG_SIGN
+extern
+void dump_signature(const char *message, const unsigned char *buffer,
+ size_t len);
+void dump_dsa_sig(const char *message, DSA_SIG *sig);
+#else
+
+# define dump_signature(a,b,c)
+# define dump_dsa_sig(a,b)
+#endif
+
+static R3410_ec_params *gost_nid2params(int nid)
+{
+ R3410_ec_params *params;
+
+ /* Search nid in 2012 paramset */
+ params = R3410_2012_512_paramset;
+ while (params->nid != NID_undef) {
+ if (params->nid == nid)
+ return params;
+ params++;
+ }
+
+ /* Search nid in 2001 paramset */
+ params = R3410_2001_paramset;
+ while (params->nid != NID_undef) {
+ if (params->nid == nid)
+ return params;
+ params++;
+ }
+
+ return NULL;
+}
+
+/*
+ * Fills EC_KEY structure hidden in the app_data field of DSA structure
+ * with parameter information, extracted from parameter array in
+ * params.c file.
+ *
+ * Also fils DSA->q field with copy of EC_GROUP order field to make
+ * DSA_size function work
+ */
+int fill_GOST_EC_params(EC_KEY *eckey, int nid)
+{
+ R3410_ec_params *params = gost_nid2params(nid);
+ EC_GROUP *grp = NULL;
+ EC_POINT *P = NULL;
+ BIGNUM *p = NULL, *q = NULL, *a = NULL, *b = NULL, *x = NULL, *y = NULL;
+ BN_CTX *ctx;
+ int ok = 0;
+
+ if (!eckey || !params) {
+ GOSTerr(GOST_F_FILL_GOST_EC_PARAMS, GOST_R_UNSUPPORTED_PARAMETER_SET);
+ return 0;
+ }
+
+ if (!(ctx = BN_CTX_new())) {
+ GOSTerr(GOST_F_FILL_GOST_EC_PARAMS, ERR_R_MALLOC_FAILURE);
+ return 0;
+ }
+
+ BN_CTX_start(ctx);
+ p = BN_CTX_get(ctx);
+ a = BN_CTX_get(ctx);
+ b = BN_CTX_get(ctx);
+ x = BN_CTX_get(ctx);
+ y = BN_CTX_get(ctx);
+ q = BN_CTX_get(ctx);
+ if (!p || !a || !b || !x || !y || !q) {
+ GOSTerr(GOST_F_FILL_GOST_EC_PARAMS, ERR_R_MALLOC_FAILURE);
+ goto end;
+ }
+
+ if (!BN_hex2bn(&p, params->p)
+ || !BN_hex2bn(&a, params->a)
+ || !BN_hex2bn(&b, params->b)) {
+ GOSTerr(GOST_F_FILL_GOST_EC_PARAMS, ERR_R_INTERNAL_ERROR);
+ goto end;
+ }
+
+ grp = EC_GROUP_new_curve_GFp(p, a, b, ctx);
+ if (!grp) {
+ GOSTerr(GOST_F_FILL_GOST_EC_PARAMS, ERR_R_MALLOC_FAILURE);
+ goto end;
+ }
+
+ P = EC_POINT_new(grp);
+ if (!P) {
+ GOSTerr(GOST_F_FILL_GOST_EC_PARAMS, ERR_R_MALLOC_FAILURE);
+ goto end;
+ }
+
+ if (!BN_hex2bn(&x, params->x)
+ || !BN_hex2bn(&y, params->y)
+ || !EC_POINT_set_affine_coordinates_GFp(grp, P, x, y, ctx)
+ || !BN_hex2bn(&q, params->q)) {
+ GOSTerr(GOST_F_FILL_GOST_EC_PARAMS, ERR_R_INTERNAL_ERROR);
+ goto end;
+ }
+
+ if (!EC_GROUP_set_generator(grp, P, q, NULL)) {
+ GOSTerr(GOST_F_FILL_GOST_EC_PARAMS, ERR_R_INTERNAL_ERROR);
+ goto end;
+ }
+ EC_GROUP_set_curve_name(grp, params->nid);
+ if (!EC_KEY_set_group(eckey, grp)) {
+ GOSTerr(GOST_F_FILL_GOST_EC_PARAMS, ERR_R_INTERNAL_ERROR);
+ goto end;
+ }
+ ok = 1;
+end:
+ if (P)
+ EC_POINT_free(P);
+ if (grp)
+ EC_GROUP_free(grp);
+ BN_CTX_end(ctx);
+ BN_CTX_free(ctx);
+ return ok;
+}
+
+/*
+ * Computes gost_ec signature as DSA_SIG structure
+ *
+ */
+DSA_SIG *gost_ec_sign(const unsigned char *dgst, int dlen, EC_KEY *eckey)
+{
+ DSA_SIG *newsig = NULL, *ret = NULL;
+ BIGNUM *md = NULL;
+ BIGNUM *order = NULL;
+ const EC_GROUP *group;
+ const BIGNUM *priv_key;
+ BIGNUM *r = NULL, *s = NULL, *X = NULL, *tmp = NULL, *tmp2 = NULL,
+ *k = NULL, *e = NULL;
+ EC_POINT *C = NULL;
+ BN_CTX *ctx;
+
+ OPENSSL_assert(dgst != NULL && eckey != NULL);
+
+ if (!(ctx = BN_CTX_new())) {
+ GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_MALLOC_FAILURE);
+ return NULL;
+ }
+
+ BN_CTX_start(ctx);
+ OPENSSL_assert(dlen == 32 || dlen == 64);
+ md = hashsum2bn(dgst, dlen);
+ newsig = DSA_SIG_new();
+ if (!newsig || !md) {
+ GOSTerr(GOST_F_GOST_EC_SIGN, GOST_R_NO_MEMORY);
+ goto err;
+ }
+ group = EC_KEY_get0_group(eckey);
+ if (!group) {
+ GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+ order = BN_CTX_get(ctx);
+ if (!order || !EC_GROUP_get_order(group, order, ctx)) {
+ GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+ priv_key = EC_KEY_get0_private_key(eckey);
+ if (!priv_key) {
+ GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+ e = BN_CTX_get(ctx);
+ if (!e || !BN_mod(e, md, order, ctx)) {
+ GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+#ifdef DEBUG_SIGN
+ fprintf(stderr, "digest as bignum=");
+ BN_print_fp(stderr, md);
+ fprintf(stderr, "\ndigest mod q=");
+ BN_print_fp(stderr, e);
+ fprintf(stderr, "\n");
+#endif
+ if (BN_is_zero(e)) {
+ BN_one(e);
+ }
+ k = BN_CTX_get(ctx);
+ C = EC_POINT_new(group);
+ if (!k || !C) {
+ GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_MALLOC_FAILURE);
+ goto err;
+ }
+
+ do {
+ do {
+ if (!BN_rand_range(k, order)) {
+ GOSTerr(GOST_F_GOST_EC_SIGN,
+ GOST_R_RANDOM_NUMBER_GENERATOR_FAILED);
+ goto err;
+ }
+ /*
+ * To avoid timing information leaking the length of k,
+ * compute C*k using an equivalent scalar of fixed bit-length */
+ if (!BN_add(k, k, order)
+ || (BN_num_bits(k) <= BN_num_bits(order)
+ && !BN_add(k, k, order))) {
+ goto err;
+ }
+ if (!EC_POINT_mul(group, C, k, NULL, NULL, ctx)) {
+ GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_EC_LIB);
+ goto err;
+ }
+ if (!X)
+ X = BN_CTX_get(ctx);
+ if (!r)
+ r = BN_CTX_get(ctx);
+ if (!X || !r) {
+ GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_MALLOC_FAILURE);
+ goto err;
+ }
+ if (!EC_POINT_get_affine_coordinates_GFp(group, C, X, NULL, ctx)) {
+ GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_EC_LIB);
+ goto err;
+ }
+
+ if (!BN_nnmod(r, X, order, ctx)) {
+ GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+ }
+ while (BN_is_zero(r));
+ /* s = (r*priv_key+k*e) mod order */
+ if (!tmp)
+ tmp = BN_CTX_get(ctx);
+ if (!tmp2)
+ tmp2 = BN_CTX_get(ctx);
+ if (!s)
+ s = BN_CTX_get(ctx);
+ if (!tmp || !tmp2 || !s) {
+ GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_MALLOC_FAILURE);
+ goto err;
+ }
+
+ if (!BN_mod_mul(tmp, priv_key, r, order, ctx)
+ || !BN_mod_mul(tmp2, k, e, order, ctx)
+ || !BN_mod_add(s, tmp, tmp2, order, ctx)) {
+ GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+ }
+ while (BN_is_zero(s));
+
+ newsig->s = BN_dup(s);
+ newsig->r = BN_dup(r);
+ if (!newsig->s || !newsig->r) {
+ GOSTerr(GOST_F_GOST_EC_SIGN, ERR_R_MALLOC_FAILURE);
+ goto err;
+ }
+
+ ret = newsig;
+ err:
+ BN_CTX_end(ctx);
+ BN_CTX_free(ctx);
+ if (C)
+ EC_POINT_free(C);
+ if (md)
+ BN_free(md);
+ if (!ret && newsig) {
+ DSA_SIG_free(newsig);
+ }
+ return ret;
+}
+
+/*
+ * Verifies gost ec signature
+ *
+ */
+int gost_ec_verify(const unsigned char *dgst, int dgst_len,
+ DSA_SIG *sig, EC_KEY *ec)
+{
+ BN_CTX *ctx;
+ const EC_GROUP *group = (ec) ? EC_KEY_get0_group(ec) : NULL;
+ BIGNUM *order;
+ BIGNUM *md = NULL, *e = NULL, *R = NULL, *v = NULL,
+ *z1 = NULL, *z2 = NULL;
+ BIGNUM *X = NULL, *tmp = NULL;
+ EC_POINT *C = NULL;
+ const EC_POINT *pub_key = NULL;
+ int ok = 0;
+
+ OPENSSL_assert(dgst != NULL && sig != NULL && group != NULL);
+
+ if (!(ctx = BN_CTX_new())) {
+ GOSTerr(GOST_F_GOST_EC_VERIFY, GOST_R_NO_MEMORY);
+ return 0;
+ }
+
+ BN_CTX_start(ctx);
+ order = BN_CTX_get(ctx);
+ e = BN_CTX_get(ctx);
+ z1 = BN_CTX_get(ctx);
+ z2 = BN_CTX_get(ctx);
+ tmp = BN_CTX_get(ctx);
+ X = BN_CTX_get(ctx);
+ R = BN_CTX_get(ctx);
+ v = BN_CTX_get(ctx);
+ if (!order || !e || !z1 || !z2 || !tmp || !X || !R || !v) {
+ GOSTerr(GOST_F_GOST_EC_VERIFY, ERR_R_MALLOC_FAILURE);
+ goto err;
+ }
+
+ pub_key = EC_KEY_get0_public_key(ec);
+ if (!pub_key || !EC_GROUP_get_order(group, order, ctx)) {
+ GOSTerr(GOST_F_GOST_EC_VERIFY, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+
+ if (BN_is_zero(sig->s) || BN_is_zero(sig->r) ||
+ (BN_cmp(sig->s, order) >= 1) || (BN_cmp(sig->r, order) >= 1)) {
+ GOSTerr(GOST_F_GOST_EC_VERIFY, GOST_R_SIGNATURE_PARTS_GREATER_THAN_Q);
+ goto err;
+
+ }
+
+ OPENSSL_assert(dgst_len == 32 || dgst_len == 64);
+ md = hashsum2bn(dgst, dgst_len);
+ if (!md || !BN_mod(e, md, order, ctx)) {
+ GOSTerr(GOST_F_GOST_EC_VERIFY, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+#ifdef DEBUG_SIGN
+ fprintf(stderr, "digest as bignum: ");
+ BN_print_fp(stderr, md);
+ fprintf(stderr, "\ndigest mod q: ");
+ BN_print_fp(stderr, e);
+#endif
+ if (BN_is_zero(e) && !BN_one(e)) {
+ GOSTerr(GOST_F_GOST_EC_VERIFY, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+ v = BN_mod_inverse(v, e, order, ctx);
+ if (!v
+ || !BN_mod_mul(z1, sig->s, v, order, ctx)
+ || !BN_sub(tmp, order, sig->r)
+ || !BN_mod_mul(z2, tmp, v, order, ctx)) {
+ GOSTerr(GOST_F_GOST_EC_VERIFY, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+#ifdef DEBUG_SIGN
+ fprintf(stderr, "\nInverted digest value: ");
+ BN_print_fp(stderr, v);
+ fprintf(stderr, "\nz1: ");
+ BN_print_fp(stderr, z1);
+ fprintf(stderr, "\nz2: ");
+ BN_print_fp(stderr, z2);
+#endif
+ C = EC_POINT_new(group);
+ if (!C) {
+ GOSTerr(GOST_F_GOST_EC_VERIFY, ERR_R_MALLOC_FAILURE);
+ goto err;
+ }
+ if (!EC_POINT_mul(group, C, z1, pub_key, z2, ctx)) {
+ GOSTerr(GOST_F_GOST_EC_VERIFY, ERR_R_EC_LIB);
+ goto err;
+ }
+ if (!EC_POINT_get_affine_coordinates_GFp(group, C, X, NULL, ctx)) {
+ GOSTerr(GOST_F_GOST_EC_VERIFY, ERR_R_EC_LIB);
+ goto err;
+ }
+ if (!BN_mod(R, X, order, ctx)) {
+ GOSTerr(GOST_F_GOST_EC_VERIFY, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+#ifdef DEBUG_SIGN
+ fprintf(stderr, "\nX=");
+ BN_print_fp(stderr, X);
+ fprintf(stderr, "\nX mod q=");
+ BN_print_fp(stderr, R);
+ fprintf(stderr, "\n");
+#endif
+ if (BN_cmp(R, sig->r) != 0) {
+ GOSTerr(GOST_F_GOST_EC_VERIFY, GOST_R_SIGNATURE_MISMATCH);
+ } else {
+ ok = 1;
+ }
+ err:
+ if (C)
+ EC_POINT_free(C);
+ BN_CTX_end(ctx);
+ BN_CTX_free(ctx);
+ if (md)
+ BN_free(md);
+ return ok;
+}
+
+/*
+ * Computes GOST R 34.10-2001 public key
+ * or GOST R 34.10-2012 public key
+ *
+ */
+int gost_ec_compute_public(EC_KEY *ec)
+{
+ const EC_GROUP *group = (ec) ? EC_KEY_get0_group(ec) : NULL;
+ EC_POINT *pub_key = NULL;
+ const BIGNUM *priv_key = NULL;
+ BN_CTX *ctx = NULL;
+ int ok = 0;
+
+ if (!group) {
+ GOSTerr(GOST_F_GOST_EC_COMPUTE_PUBLIC, GOST_R_KEY_IS_NOT_INITIALIZED);
+ return 0;
+ }
+
+ ctx = BN_CTX_new();
+ if (!ctx) {
+ GOSTerr(GOST_F_GOST_EC_COMPUTE_PUBLIC, ERR_R_MALLOC_FAILURE);
+ return 0;
+ }
+
+ BN_CTX_start(ctx);
+ priv_key = EC_KEY_get0_private_key(ec);
+ if (!priv_key) {
+ GOSTerr(GOST_F_GOST_EC_COMPUTE_PUBLIC, ERR_R_EC_LIB);
+ goto err;
+ }
+
+ pub_key = EC_POINT_new(group);
+ if (!pub_key) {
+ GOSTerr(GOST_F_GOST_EC_COMPUTE_PUBLIC, ERR_R_MALLOC_FAILURE);
+ goto err;
+ }
+
+ if (!EC_POINT_mul(group, pub_key, priv_key, NULL, NULL, ctx)) {
+ GOSTerr(GOST_F_GOST_EC_COMPUTE_PUBLIC, ERR_R_EC_LIB);
+ goto err;
+ }
+ if (!EC_KEY_set_public_key(ec, pub_key)) {
+ GOSTerr(GOST_F_GOST_EC_COMPUTE_PUBLIC, ERR_R_EC_LIB);
+ goto err;
+ }
+ ok = 1;
+ err:
+ if (pub_key)
+ EC_POINT_free(pub_key);
+ BN_CTX_end(ctx);
+ BN_CTX_free(ctx);
+ return ok;
+}
+
+/*
+ *
+ * Generates GOST R 34.10-2001
+ * or GOST R 34.10-2012 keypair
+ *
+ */
+int gost_ec_keygen(EC_KEY *ec)
+{
+ BIGNUM *order = NULL, *d = NULL;
+ const EC_GROUP *group = (ec) ? EC_KEY_get0_group(ec) : NULL;
+ int ok = 0;
+
+ if (!group) {
+ GOSTerr(GOST_F_GOST_EC_KEYGEN, ERR_R_INTERNAL_ERROR);
+ return 0;
+ }
+
+ order = BN_new();
+ d = BN_new();
+ if (!order || !d) {
+ GOSTerr(GOST_F_GOST_EC_KEYGEN, ERR_R_MALLOC_FAILURE);
+ goto end;
+ }
+
+ if (!EC_GROUP_get_order(group, order, NULL)) {
+ GOSTerr(GOST_F_GOST_EC_KEYGEN, ERR_R_INTERNAL_ERROR);
+ goto end;
+ }
+
+ do {
+ if (!BN_rand_range(d, order)) {
+ GOSTerr(GOST_F_GOST_EC_KEYGEN,
+ GOST_R_RANDOM_NUMBER_GENERATOR_FAILED);
+ goto end;
+ }
+ }
+ while (BN_is_zero(d));
+
+ if (!EC_KEY_set_private_key(ec, d)) {
+ GOSTerr(GOST_F_GOST_EC_KEYGEN, ERR_R_INTERNAL_ERROR);
+ goto end;
+ }
+
+ ok = 1;
+end:
+ if (d)
+ BN_free(d);
+ if (order)
+ BN_free(order);
+
+ return (ok) ? gost_ec_compute_public(ec) : 0;
+}
projects / openssl-gost / engine.git / blobdiff