X-Git-Url: https://wagner.pp.ru/gitweb/?a=blobdiff_plain;f=gost_ec_sign.c;h=f7b8966d01801b4b057b7e80f1d31e5f85a77171;hb=13dc9c81e30ce1d44d76aba6c35bf8bb3b3bcf2d;hp=e4800a461d1452d77991619010567fbef6ad3875;hpb=83e1771145d9b9f40cc5edb5af9c9f45ea4ca71a;p=openssl-gost%2Fengine.git diff --git a/gost_ec_sign.c b/gost_ec_sign.c index e4800a4..f7b8966 100644 --- a/gost_ec_sign.c +++ b/gost_ec_sign.c @@ -613,3 +613,174 @@ int gost_ec_keygen(EC_KEY *ec) return (ok) ? gost_ec_compute_public(ec) : 0; } + +int gost_ec_oct2point(const EC_GROUP *group, EC_POINT *point, + const unsigned char *buf, size_t len) +{ + BN_CTX *ctx = NULL; + BIGNUM *x, *y, *p; + size_t field_len, enc_len; + int ret = 0; + + if (len == 0) { + GOSTerr(GOST_F_GOST_EC_OCT2POINT, EC_R_BUFFER_TOO_SMALL); + return 0; + } + + field_len = (EC_GROUP_get_degree(group) + 7) / 8; + enc_len = 2 * field_len; + + if (len != enc_len) { + GOSTerr(GOST_F_GOST_EC_OCT2POINT, EC_R_INVALID_ENCODING); + return 0; + } + + ctx = BN_CTX_new(); + if (ctx == NULL) + return 0; + + BN_CTX_start(ctx); + x = BN_CTX_get(ctx); + y = BN_CTX_get(ctx); + p = BN_CTX_get(ctx); + if (y == NULL) + goto err; + + if (!EC_GROUP_get_curve(group, p, NULL, NULL, NULL)) + goto err; + + if (!BN_lebin2bn(buf, field_len, x)) + goto err; + if (BN_ucmp(x, p) >= 0) { + GOSTerr(GOST_F_GOST_EC_OCT2POINT, EC_R_INVALID_ENCODING); + goto err; + } + + if (!BN_lebin2bn(buf + field_len, field_len, y)) + goto err; + if (BN_ucmp(y, p) >= 0) { + GOSTerr(GOST_F_GOST_EC_OCT2POINT, EC_R_INVALID_ENCODING); + goto err; + } + + /* + * EC_POINT_set_affine_coordinates is responsible for checking that + * the point is on the curve. + */ + if (!EC_POINT_set_affine_coordinates(group, point, x, y, ctx)) + goto err; + + ret = 1; + + err: + BN_CTX_end(ctx); + BN_CTX_free(ctx); + return ret; +} + + +size_t gost_ec_point2oct(const EC_GROUP *group, const EC_POINT *point, + unsigned char *buf, size_t len) +{ + size_t ret; + BN_CTX *ctx = NULL; + int used_ctx = 0; + BIGNUM *x, *y; + size_t field_len; + + field_len = (EC_GROUP_get_degree(group) + 7) / 8; + ret = 2 * field_len; + + if (buf != NULL) { + if (len < ret) { + GOSTerr(GOST_F_GOST_EC_POINT2OCT, EC_R_BUFFER_TOO_SMALL); + goto err; + } + + ctx = BN_CTX_new(); + if (ctx == NULL) + return 0; + + BN_CTX_start(ctx); + used_ctx = 1; + x = BN_CTX_get(ctx); + y = BN_CTX_get(ctx); + if (y == NULL) + goto err; + + if (!EC_POINT_get_affine_coordinates(group, point, x, y, ctx)) + goto err; + + if (BN_bn2lebinpad(x, buf, field_len) != field_len + || BN_bn2lebinpad(y, buf + field_len, field_len) != field_len) + goto err; + } + + if (used_ctx) + BN_CTX_end(ctx); + BN_CTX_free(ctx); + return ret; + + err: + if (used_ctx) + BN_CTX_end(ctx); + BN_CTX_free(ctx); + return 0; +} + +size_t gost_ec_key2buf(const EC_KEY *key, unsigned char **pbuf) +{ + size_t len; + unsigned char *buf; + const EC_GROUP *grp = NULL; + const EC_POINT *pkey = NULL; + + pkey = EC_KEY_get0_public_key(key); + grp = EC_KEY_get0_group(key); + + if(pkey == NULL || grp == NULL) + return 0; + + len = gost_ec_point2oct(grp, pkey, NULL, 0); + if (len == 0) + return 0; + if ((buf = OPENSSL_malloc(len)) == NULL) { + GOSTerr(GOST_F_GOST_EC_KEY2BUF, ERR_R_MALLOC_FAILURE); + return 0; + } + len = gost_ec_point2oct(grp, pkey, buf, len); + if (len == 0) { + OPENSSL_free(buf); + return 0; + } + *pbuf = buf; + return len; +} + +int gost_ec_oct2key(EC_KEY *key, const unsigned char *buf, size_t len) +{ + const EC_GROUP *group = NULL; + const EC_POINT *pub_key = NULL; + EC_POINT *point = NULL; + int ok = 0; + + if (key == NULL || (group = EC_KEY_get0_group(key)) == NULL) + return 0; + + if ((pub_key = EC_KEY_get0_public_key(key)) == NULL) { + if((point = EC_POINT_new(group)) == NULL || + !EC_KEY_set_public_key(key, point)) + goto err; + pub_key = EC_KEY_get0_public_key(key); + } + + if (gost_ec_oct2point(group, (EC_POINT *)pub_key, buf, len) == 0) + goto err; + + ok = 1; + + err: + if (point) + EC_POINT_free(point); + return ok; +}