static ECDH_DATA *ECDH_DATA_new_method(ENGINE *engine) { ECDH_DATA *ret; ret = OPENSSL_malloc(sizeof(*ret)); if (ret == NULL) { ECDHerr(ECDH_F_ECDH_DATA_NEW_METHOD, ERR_R_MALLOC_FAILURE); return (NULL); } ret->init = NULL; ret->meth = ECDH_get_default_method(); ret->engine = engine; #ifndef OPENSSL_NO_ENGINE if (!ret->engine) ret->engine = ENGINE_get_default_ECDH(); if (ret->engine) { ret->meth = ENGINE_get_ECDH(ret->engine); if (!ret->meth) { ECDHerr(ECDH_F_ECDH_DATA_NEW_METHOD, ERR_R_ENGINE_LIB); ENGINE_finish(ret->engine); OPENSSL_free(ret); return NULL; } } #endif ret->flags = ret->meth->flags; CRYPTO_new_ex_data(CRYPTO_EX_INDEX_ECDH, ret, &ret->ex_data); return (ret); }
int ecdh_gm_compute_key(PACE_CTX * ctx, const BUF_MEM * s, const BUF_MEM * in, BN_CTX *bn_ctx) { int ret = 0; BUF_MEM * mem_h = NULL; BIGNUM * bn_s = NULL, *order = NULL, *cofactor = NULL; EC_POINT * ecp_h = NULL, *ecp_g = NULL; const ECDH_METHOD *default_method; EC_GROUP *group = NULL; EC_KEY *static_key = NULL, *ephemeral_key = NULL; BN_CTX_start(bn_ctx); check((ctx && ctx->static_key && s && ctx->ka_ctx), "Invalid arguments"); static_key = EVP_PKEY_get1_EC_KEY(ctx->static_key); check(static_key, "could not get key object"); /* Extract group parameters */ group = EC_GROUP_dup(EC_KEY_get0_group(static_key)); order = BN_CTX_get(bn_ctx); cofactor = BN_CTX_get(bn_ctx); check(group && cofactor, "internal error"); if (!EC_GROUP_get_order(group, order, bn_ctx) || !EC_GROUP_get_cofactor(group, cofactor, bn_ctx)) goto err; /* Convert nonce to BIGNUM */ bn_s = BN_bin2bn((unsigned char *) s->data, s->length, bn_s); if (!bn_s) goto err; default_method = ECDH_get_default_method(); ECDH_set_default_method(ECDH_OpenSSL_Point()); /* complete the ECDH and get the resulting point h */ mem_h = ecdh_compute_key(ctx->static_key, in, bn_ctx); ECDH_set_default_method(default_method); ecp_h = EC_POINT_new(group); if (!mem_h || !ecp_h || !EC_POINT_oct2point(group, ecp_h, (unsigned char *) mem_h->data, mem_h->length, bn_ctx)) goto err; /* map to new generator */ ecp_g = EC_POINT_new(group); /* g' = g*s + h*1 */ if (!EC_POINT_mul(group, ecp_g, bn_s, ecp_h, BN_value_one(), bn_ctx)) goto err; /* Initialize ephemeral parameters with parameters from the static key */ ephemeral_key = EC_KEY_dup(static_key); if (!ephemeral_key) goto err; EVP_PKEY_set1_EC_KEY(ctx->ka_ctx->key, ephemeral_key); /* configure the new EC_KEY */ if (!EC_GROUP_set_generator(group, ecp_g, order, cofactor) || !EC_GROUP_check(group, bn_ctx) || !EC_KEY_set_group(ephemeral_key, group)) goto err; ret = 1; err: if (ecp_g) EC_POINT_clear_free(ecp_g); if (ecp_h) EC_POINT_clear_free(ecp_h); if (mem_h) BUF_MEM_free(mem_h); if (bn_s) BN_clear_free(bn_s); BN_CTX_end(bn_ctx); /* Decrement reference count, keys are still available via PACE_CTX */ if (static_key) EC_KEY_free(static_key); if (ephemeral_key) EC_KEY_free(ephemeral_key); if (group) EC_GROUP_clear_free(group); return ret; }