X-Git-Url: https://git.openssl.org/?p=openssl.git;a=blobdiff_plain;f=crypto%2Fec%2Fec_key.c;h=aae31719076a6076adefed6a40367230a7d2d41c;hp=2469edcd2f7cf399eab39e97c98ed22fda7ca8be;hb=6b4eb933623ed1d1997732b7e6e081b788cfdd22;hpb=dd67493c344d9d98413d2ee7fd2b6fa9411d975c diff --git a/crypto/ec/ec_key.c b/crypto/ec/ec_key.c index 2469edcd2f..aae3171907 100644 --- a/crypto/ec/ec_key.c +++ b/crypto/ec/ec_key.c @@ -1,85 +1,49 @@ -/* crypto/ec/ec_key.c */ /* - * Written by Nils Larsch for the OpenSSL project. - */ -/* ==================================================================== - * Copyright (c) 1998-2005 The OpenSSL Project. All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in - * the documentation and/or other materials provided with the - * distribution. - * - * 3. All advertising materials mentioning features or use of this - * software must display the following acknowledgment: - * "This product includes software developed by the OpenSSL Project - * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" - * - * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to - * endorse or promote products derived from this software without - * prior written permission. For written permission, please contact - * openssl-core@openssl.org. - * - * 5. Products derived from this software may not be called "OpenSSL" - * nor may "OpenSSL" appear in their names without prior written - * permission of the OpenSSL Project. - * - * 6. Redistributions of any form whatsoever must retain the following - * acknowledgment: - * "This product includes software developed by the OpenSSL Project - * for use in the OpenSSL Toolkit (http://www.openssl.org/)" - * - * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY - * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR - * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR - * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, - * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT - * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; - * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, - * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) - * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED - * OF THE POSSIBILITY OF SUCH DAMAGE. - * ==================================================================== - * - * This product includes cryptographic software written by Eric Young - * (eay@cryptsoft.com). This product includes software written by Tim - * Hudson (tjh@cryptsoft.com). + * Copyright 2002-2020 The OpenSSL Project Authors. All Rights Reserved. + * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved * + * Licensed under the Apache License 2.0 (the "License"). You may not use + * this file except in compliance with the License. You can obtain a copy + * in the file LICENSE in the source distribution or at + * https://www.openssl.org/source/license.html */ -/* ==================================================================== - * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED. - * Portions originally developed by SUN MICROSYSTEMS, INC., and - * contributed to the OpenSSL project. + +/* + * ECDSA low level APIs are deprecated for public use, but still ok for + * internal use. */ +#include "internal/deprecated.h" -#include +#include "internal/cryptlib.h" #include -#include "ec_lcl.h" +#include "ec_local.h" +#include "internal/refcount.h" #include -#ifndef OPENSSL_NO_ENGINE -# include -#endif +#include +#include +#include "crypto/bn.h" +static int ecdsa_keygen_pairwise_test(EC_KEY *eckey, OSSL_CALLBACK *cb, + void *cbarg); + +#ifndef FIPS_MODULE EC_KEY *EC_KEY_new(void) { - return EC_KEY_new_method(NULL); + return ec_key_new_method_int(NULL, NULL); } +#endif -EC_KEY *EC_KEY_new_by_curve_name(int nid) +EC_KEY *EC_KEY_new_ex(OPENSSL_CTX *ctx) +{ + return ec_key_new_method_int(ctx, NULL); +} + +EC_KEY *EC_KEY_new_by_curve_name_ex(OPENSSL_CTX *ctx, int nid) { - EC_KEY *ret = EC_KEY_new(); + EC_KEY *ret = EC_KEY_new_ex(ctx); if (ret == NULL) return NULL; - ret->group = EC_GROUP_new_by_curve_name(nid); + ret->group = EC_GROUP_new_by_curve_name_ex(ctx, nid); if (ret->group == NULL) { EC_KEY_free(ret); return NULL; @@ -92,6 +56,13 @@ EC_KEY *EC_KEY_new_by_curve_name(int nid) return ret; } +#ifndef FIPS_MODULE +EC_KEY *EC_KEY_new_by_curve_name(int nid) +{ + return EC_KEY_new_by_curve_name_ex(NULL, nid); +} +#endif + void EC_KEY_free(EC_KEY *r) { int i; @@ -99,28 +70,26 @@ void EC_KEY_free(EC_KEY *r) if (r == NULL) return; - i = CRYPTO_add(&r->references, -1, CRYPTO_LOCK_EC); -#ifdef REF_PRINT - REF_PRINT("EC_KEY", r); -#endif + CRYPTO_DOWN_REF(&r->references, &i, r->lock); + REF_PRINT_COUNT("EC_KEY", r); if (i > 0) return; -#ifdef REF_CHECK - if (i < 0) { - fprintf(stderr, "EC_KEY_free, bad reference count\n"); - abort(); - } -#endif + REF_ASSERT_ISNT(i < 0); - if (r->meth->finish != NULL) + if (r->meth != NULL && r->meth->finish != NULL) r->meth->finish(r); -#ifndef OPENSSL_NO_ENGINE - if (r->engine != NULL) - ENGINE_finish(r->engine); +#if !defined(OPENSSL_NO_ENGINE) && !defined(FIPS_MODULE) + ENGINE_finish(r->engine); #endif + if (r->group && r->group->meth->keyfinish) + r->group->meth->keyfinish(r); + +#ifndef FIPS_MODULE CRYPTO_free_ex_data(CRYPTO_EX_INDEX_EC_KEY, r, &r->ex_data); +#endif + CRYPTO_THREAD_lock_free(r->lock); EC_GROUP_free(r->group); EC_POINT_free(r->pub_key); BN_clear_free(r->priv_key); @@ -128,7 +97,7 @@ void EC_KEY_free(EC_KEY *r) OPENSSL_clear_free((void *)r, sizeof(EC_KEY)); } -EC_KEY *EC_KEY_copy(EC_KEY *dest, EC_KEY *src) +EC_KEY *EC_KEY_copy(EC_KEY *dest, const EC_KEY *src) { if (dest == NULL || src == NULL) { ECerr(EC_F_EC_KEY_COPY, ERR_R_PASSED_NULL_PARAMETER); @@ -137,54 +106,64 @@ EC_KEY *EC_KEY_copy(EC_KEY *dest, EC_KEY *src) if (src->meth != dest->meth) { if (dest->meth->finish != NULL) dest->meth->finish(dest); -#ifndef OPENSSL_NO_ENGINE - if (dest->engine != NULL && ENGINE_finish(dest->engine) == 0) + if (dest->group && dest->group->meth->keyfinish) + dest->group->meth->keyfinish(dest); +#if !defined(OPENSSL_NO_ENGINE) && !defined(FIPS_MODULE) + if (ENGINE_finish(dest->engine) == 0) return 0; dest->engine = NULL; #endif } + dest->libctx = src->libctx; /* copy the parameters */ if (src->group != NULL) { const EC_METHOD *meth = EC_GROUP_method_of(src->group); /* clear the old group */ EC_GROUP_free(dest->group); - dest->group = EC_GROUP_new(meth); + dest->group = EC_GROUP_new_ex(src->libctx, meth); if (dest->group == NULL) return NULL; if (!EC_GROUP_copy(dest->group, src->group)) return NULL; - } - /* copy the public key */ - if (src->pub_key != NULL && src->group != NULL) { - EC_POINT_free(dest->pub_key); - dest->pub_key = EC_POINT_new(src->group); - if (dest->pub_key == NULL) - return NULL; - if (!EC_POINT_copy(dest->pub_key, src->pub_key)) - return NULL; - } - /* copy the private key */ - if (src->priv_key != NULL) { - if (dest->priv_key == NULL) { - dest->priv_key = BN_new(); - if (dest->priv_key == NULL) + + /* copy the public key */ + if (src->pub_key != NULL) { + EC_POINT_free(dest->pub_key); + dest->pub_key = EC_POINT_new(src->group); + if (dest->pub_key == NULL) + return NULL; + if (!EC_POINT_copy(dest->pub_key, src->pub_key)) + return NULL; + } + /* copy the private key */ + if (src->priv_key != NULL) { + if (dest->priv_key == NULL) { + dest->priv_key = BN_new(); + if (dest->priv_key == NULL) + return NULL; + } + if (!BN_copy(dest->priv_key, src->priv_key)) + return NULL; + if (src->group->meth->keycopy + && src->group->meth->keycopy(dest, src) == 0) return NULL; } - if (!BN_copy(dest->priv_key, src->priv_key)) - return NULL; } + /* copy the rest */ dest->enc_flag = src->enc_flag; dest->conv_form = src->conv_form; dest->version = src->version; dest->flags = src->flags; +#ifndef FIPS_MODULE if (!CRYPTO_dup_ex_data(CRYPTO_EX_INDEX_EC_KEY, &dest->ex_data, &src->ex_data)) return NULL; +#endif if (src->meth != dest->meth) { -#ifndef OPENSSL_NO_ENGINE +#if !defined(OPENSSL_NO_ENGINE) && !defined(FIPS_MODULE) if (src->engine != NULL && ENGINE_init(src->engine) == 0) return NULL; dest->engine = src->engine; @@ -195,15 +174,18 @@ EC_KEY *EC_KEY_copy(EC_KEY *dest, EC_KEY *src) if (src->meth->copy != NULL && src->meth->copy(dest, src) == 0) return NULL; + dest->dirty_cnt++; + return dest; } -EC_KEY *EC_KEY_dup(EC_KEY *ec_key) +EC_KEY *EC_KEY_dup(const EC_KEY *ec_key) { - EC_KEY *ret = EC_KEY_new_method(ec_key->engine); + EC_KEY *ret = ec_key_new_method_int(ec_key->libctx, ec_key->engine); if (ret == NULL) return NULL; + if (EC_KEY_copy(ret, ec_key) == NULL) { EC_KEY_free(ret); return NULL; @@ -213,148 +195,376 @@ EC_KEY *EC_KEY_dup(EC_KEY *ec_key) int EC_KEY_up_ref(EC_KEY *r) { - int i = CRYPTO_add(&r->references, 1, CRYPTO_LOCK_EC); -#ifdef REF_PRINT - REF_PRINT("EC_KEY", r); -#endif -#ifdef REF_CHECK - if (i < 2) { - fprintf(stderr, "EC_KEY_up, bad reference count\n"); - abort(); - } -#endif + int i; + + if (CRYPTO_UP_REF(&r->references, &i, r->lock) <= 0) + return 0; + + REF_PRINT_COUNT("EC_KEY", r); + REF_ASSERT_ISNT(i < 2); return ((i > 1) ? 1 : 0); } +ENGINE *EC_KEY_get0_engine(const EC_KEY *eckey) +{ + return eckey->engine; +} + int EC_KEY_generate_key(EC_KEY *eckey) { if (eckey == NULL || eckey->group == NULL) { ECerr(EC_F_EC_KEY_GENERATE_KEY, ERR_R_PASSED_NULL_PARAMETER); return 0; } - if (eckey->meth->keygen != NULL) - return eckey->meth->keygen(eckey); + if (eckey->meth->keygen != NULL) { + int ret; + + ret = eckey->meth->keygen(eckey); + if (ret == 1) + eckey->dirty_cnt++; + + return ret; + } ECerr(EC_F_EC_KEY_GENERATE_KEY, EC_R_OPERATION_NOT_SUPPORTED); return 0; } int ossl_ec_key_gen(EC_KEY *eckey) +{ + int ret; + + ret = eckey->group->meth->keygen(eckey); + + if (ret == 1) + eckey->dirty_cnt++; + return ret; +} + +/* + * ECC Key generation. + * See SP800-56AR3 5.6.1.2.2 "Key Pair Generation by Testing Candidates" + * + * Params: + * libctx A context containing an optional self test callback. + * eckey An EC key object that contains domain params. The generated keypair + * is stored in this object. + * pairwise_test Set to non zero to perform a pairwise test. If the test + * fails then the keypair is not generated, + * Returns 1 if the keypair was generated or 0 otherwise. + */ +int ec_generate_key(OPENSSL_CTX *libctx, EC_KEY *eckey, int pairwise_test) { int ok = 0; - BN_CTX *ctx = NULL; - BIGNUM *priv_key = NULL, *order = NULL; + BIGNUM *priv_key = NULL; + const BIGNUM *order = NULL; EC_POINT *pub_key = NULL; + const EC_GROUP *group = eckey->group; + BN_CTX *ctx = BN_CTX_secure_new_ex(eckey->libctx); - if ((order = BN_new()) == NULL) - goto err; - if ((ctx = BN_CTX_new()) == NULL) + if (ctx == NULL) goto err; if (eckey->priv_key == NULL) { - priv_key = BN_new(); + priv_key = BN_secure_new(); if (priv_key == NULL) goto err; } else priv_key = eckey->priv_key; - if (!EC_GROUP_get_order(eckey->group, order, ctx)) + /* + * Steps (1-2): Check domain parameters and security strength. + * These steps must be done by the user. This would need to be + * stated in the security policy. + */ + + order = EC_GROUP_get0_order(group); + if (order == NULL) goto err; + /* + * Steps (3-7): priv_key = DRBG_RAND(order_n_bits) (range [1, n-1]). + * Although this is slightly different from the standard, it is effectively + * equivalent as it gives an unbiased result ranging from 1..n-1. It is also + * faster as the standard needs to retry more often. Also doing + * 1 + rand[0..n-2] would effect the way that tests feed dummy entropy into + * rand so the simpler backward compatible method has been used here. + */ do - if (!BN_rand_range(priv_key, order)) + if (!BN_priv_rand_range_ex(priv_key, order, ctx)) goto err; while (BN_is_zero(priv_key)) ; if (eckey->pub_key == NULL) { - pub_key = EC_POINT_new(eckey->group); + pub_key = EC_POINT_new(group); if (pub_key == NULL) goto err; } else pub_key = eckey->pub_key; - if (!EC_POINT_mul(eckey->group, pub_key, priv_key, NULL, NULL, ctx)) + /* Step (8) : pub_key = priv_key * G (where G is a point on the curve) */ + if (!EC_POINT_mul(group, pub_key, priv_key, NULL, NULL, ctx)) goto err; eckey->priv_key = priv_key; eckey->pub_key = pub_key; + priv_key = NULL; + pub_key = NULL; + + eckey->dirty_cnt++; + +#ifdef FIPS_MODULE + pairwise_test = 1; +#endif /* FIPS_MODULE */ ok = 1; + if (pairwise_test) { + OSSL_CALLBACK *cb = NULL; + void *cbarg = NULL; - err: - BN_free(order); - if (eckey->pub_key == NULL) - EC_POINT_free(pub_key); - if (eckey->priv_key != priv_key) - BN_free(priv_key); + OSSL_SELF_TEST_get_callback(libctx, &cb, &cbarg); + ok = ecdsa_keygen_pairwise_test(eckey, cb, cbarg); + } +err: + /* Step (9): If there is an error return an invalid keypair. */ + if (!ok) { + BN_clear(eckey->priv_key); + if (eckey->pub_key != NULL) + EC_POINT_set_to_infinity(group, eckey->pub_key); + } + + EC_POINT_free(pub_key); + BN_clear_free(priv_key); BN_CTX_free(ctx); - return (ok); + return ok; +} + +int ec_key_simple_generate_key(EC_KEY *eckey) +{ + return ec_generate_key(NULL, eckey, 0); +} + +int ec_key_simple_generate_public_key(EC_KEY *eckey) +{ + int ret; + + /* + * See SP800-56AR3 5.6.1.2.2: Step (8) + * pub_key = priv_key * G (where G is a point on the curve) + */ + ret = EC_POINT_mul(eckey->group, eckey->pub_key, eckey->priv_key, NULL, + NULL, NULL); + + if (ret == 1) + eckey->dirty_cnt++; + + return ret; } int EC_KEY_check_key(const EC_KEY *eckey) { - int ok = 0; - BN_CTX *ctx = NULL; - const BIGNUM *order = NULL; + if (eckey == NULL || eckey->group == NULL || eckey->pub_key == NULL) { + ECerr(EC_F_EC_KEY_CHECK_KEY, ERR_R_PASSED_NULL_PARAMETER); + return 0; + } + + if (eckey->group->meth->keycheck == NULL) { + ECerr(EC_F_EC_KEY_CHECK_KEY, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED); + return 0; + } + + return eckey->group->meth->keycheck(eckey); +} + +/* + * Check the range of the EC public key. + * See SP800-56A R3 Section 5.6.2.3.3 (Part 2) + * i.e. + * - If q = odd prime p: Verify that xQ and yQ are integers in the + * interval[0, p - 1], OR + * - If q = 2m: Verify that xQ and yQ are bit strings of length m bits. + * Returns 1 if the public key has a valid range, otherwise it returns 0. + */ +static int ec_key_public_range_check(BN_CTX *ctx, const EC_KEY *key) +{ + int ret = 0; + BIGNUM *x, *y; + + BN_CTX_start(ctx); + x = BN_CTX_get(ctx); + y = BN_CTX_get(ctx); + if (y == NULL) + goto err; + + if (!EC_POINT_get_affine_coordinates(key->group, key->pub_key, x, y, ctx)) + goto err; + + if (EC_METHOD_get_field_type(key->group->meth) == NID_X9_62_prime_field) { + if (BN_is_negative(x) + || BN_cmp(x, key->group->field) >= 0 + || BN_is_negative(y) + || BN_cmp(y, key->group->field) >= 0) { + goto err; + } + } else { + int m = EC_GROUP_get_degree(key->group); + if (BN_num_bits(x) > m || BN_num_bits(y) > m) { + goto err; + } + } + ret = 1; +err: + BN_CTX_end(ctx); + return ret; +} + +/* + * ECC Key validation as specified in SP800-56A R3. + * Section 5.6.2.3.3 ECC Full Public-Key Validation. + */ +int ec_key_public_check(const EC_KEY *eckey, BN_CTX *ctx) +{ + int ret = 0; EC_POINT *point = NULL; + const BIGNUM *order = NULL; if (eckey == NULL || eckey->group == NULL || eckey->pub_key == NULL) { - ECerr(EC_F_EC_KEY_CHECK_KEY, ERR_R_PASSED_NULL_PARAMETER); + ECerr(0, ERR_R_PASSED_NULL_PARAMETER); return 0; } + /* 5.6.2.3.3 (Step 1): Q != infinity */ if (EC_POINT_is_at_infinity(eckey->group, eckey->pub_key)) { - ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_POINT_AT_INFINITY); - goto err; + ECerr(0, EC_R_POINT_AT_INFINITY); + return 0; } - if ((ctx = BN_CTX_new()) == NULL) - goto err; - if ((point = EC_POINT_new(eckey->group)) == NULL) + point = EC_POINT_new(eckey->group); + if (point == NULL) + return 0; + + /* 5.6.2.3.3 (Step 2) Test if the public key is in range */ + if (!ec_key_public_range_check(ctx, eckey)) { + ECerr(0, EC_R_COORDINATES_OUT_OF_RANGE); goto err; + } - /* testing whether the pub_key is on the elliptic curve */ + /* 5.6.2.3.3 (Step 3) is the pub_key on the elliptic curve */ if (EC_POINT_is_on_curve(eckey->group, eckey->pub_key, ctx) <= 0) { - ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_POINT_IS_NOT_ON_CURVE); + ECerr(0, EC_R_POINT_IS_NOT_ON_CURVE); goto err; } - /* testing whether pub_key * order is the point at infinity */ + order = eckey->group->order; if (BN_is_zero(order)) { - ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_INVALID_GROUP_ORDER); + ECerr(0, EC_R_INVALID_GROUP_ORDER); goto err; } + /* 5.6.2.3.3 (Step 4) : pub_key * order is the point at infinity. */ if (!EC_POINT_mul(eckey->group, point, NULL, eckey->pub_key, order, ctx)) { - ECerr(EC_F_EC_KEY_CHECK_KEY, ERR_R_EC_LIB); + ECerr(0, ERR_R_EC_LIB); goto err; } if (!EC_POINT_is_at_infinity(eckey->group, point)) { - ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_WRONG_ORDER); + ECerr(0, EC_R_WRONG_ORDER); goto err; } - /* - * in case the priv_key is present : check if generator * priv_key == - * pub_key - */ + ret = 1; +err: + EC_POINT_free(point); + return ret; +} + +/* + * ECC Key validation as specified in SP800-56A R3. + * Section 5.6.2.1.2 Owner Assurance of Private-Key Validity + * The private key is in the range [1, order-1] + */ +int ec_key_private_check(const EC_KEY *eckey) +{ + if (eckey == NULL || eckey->group == NULL || eckey->priv_key == NULL) { + ECerr(0, ERR_R_PASSED_NULL_PARAMETER); + return 0; + } + if (BN_cmp(eckey->priv_key, BN_value_one()) < 0 + || BN_cmp(eckey->priv_key, eckey->group->order) >= 0) { + ECerr(0, EC_R_INVALID_PRIVATE_KEY); + return 0; + } + return 1; +} + +/* + * ECC Key validation as specified in SP800-56A R3. + * Section 5.6.2.1.4 Owner Assurance of Pair-wise Consistency (b) + * Check if generator * priv_key = pub_key + */ +int ec_key_pairwise_check(const EC_KEY *eckey, BN_CTX *ctx) +{ + int ret = 0; + EC_POINT *point = NULL; + + if (eckey == NULL + || eckey->group == NULL + || eckey->pub_key == NULL + || eckey->priv_key == NULL) { + ECerr(0, ERR_R_PASSED_NULL_PARAMETER); + return 0; + } + + point = EC_POINT_new(eckey->group); + if (point == NULL) + goto err; + + + if (!EC_POINT_mul(eckey->group, point, eckey->priv_key, NULL, NULL, ctx)) { + ECerr(0, ERR_R_EC_LIB); + goto err; + } + if (EC_POINT_cmp(eckey->group, point, eckey->pub_key, ctx) != 0) { + ECerr(0, EC_R_INVALID_PRIVATE_KEY); + goto err; + } + ret = 1; +err: + EC_POINT_free(point); + return ret; +} + + +/* + * ECC Key validation as specified in SP800-56A R3. + * Section 5.6.2.3.3 ECC Full Public-Key Validation + * Section 5.6.2.1.2 Owner Assurance of Private-Key Validity + * Section 5.6.2.1.4 Owner Assurance of Pair-wise Consistency + * NOTES: + * Before calling this method in fips mode, there should be an assurance that + * an approved elliptic-curve group is used. + * Returns 1 if the key is valid, otherwise it returns 0. + */ +int ec_key_simple_check_key(const EC_KEY *eckey) +{ + int ok = 0; + BN_CTX *ctx = NULL; + + if (eckey == NULL) { + ECerr(0, ERR_R_PASSED_NULL_PARAMETER); + return 0; + } + if ((ctx = BN_CTX_new_ex(eckey->libctx)) == NULL) + return 0; + + if (!ec_key_public_check(eckey, ctx)) + goto err; + if (eckey->priv_key != NULL) { - if (BN_cmp(eckey->priv_key, order) >= 0) { - ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_WRONG_ORDER); + if (!ec_key_private_check(eckey) + || !ec_key_pairwise_check(eckey, ctx)) goto err; - } - if (!EC_POINT_mul(eckey->group, point, eckey->priv_key, - NULL, NULL, ctx)) { - ECerr(EC_F_EC_KEY_CHECK_KEY, ERR_R_EC_LIB); - goto err; - } - if (EC_POINT_cmp(eckey->group, point, eckey->pub_key, ctx) != 0) { - ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_INVALID_PRIVATE_KEY); - goto err; - } } ok = 1; - err: +err: BN_CTX_free(ctx); - EC_POINT_free(point); - return (ok); + return ok; } int EC_KEY_set_public_key_affine_coordinates(EC_KEY *key, BIGNUM *x, @@ -364,19 +574,17 @@ int EC_KEY_set_public_key_affine_coordinates(EC_KEY *key, BIGNUM *x, BIGNUM *tx, *ty; EC_POINT *point = NULL; int ok = 0; -#ifndef OPENSSL_NO_EC2M - int tmp_nid, is_char_two = 0; -#endif if (key == NULL || key->group == NULL || x == NULL || y == NULL) { ECerr(EC_F_EC_KEY_SET_PUBLIC_KEY_AFFINE_COORDINATES, ERR_R_PASSED_NULL_PARAMETER); return 0; } - ctx = BN_CTX_new(); + ctx = BN_CTX_new_ex(key->libctx); if (ctx == NULL) - goto err; + return 0; + BN_CTX_start(ctx); point = EC_POINT_new(key->group); if (point == NULL) @@ -387,41 +595,22 @@ int EC_KEY_set_public_key_affine_coordinates(EC_KEY *key, BIGNUM *x, if (ty == NULL) goto err; -#ifndef OPENSSL_NO_EC2M - tmp_nid = EC_METHOD_get_field_type(EC_GROUP_method_of(key->group)); - - if (tmp_nid == NID_X9_62_characteristic_two_field) - is_char_two = 1; + if (!EC_POINT_set_affine_coordinates(key->group, point, x, y, ctx)) + goto err; + if (!EC_POINT_get_affine_coordinates(key->group, point, tx, ty, ctx)) + goto err; - if (is_char_two) { - if (!EC_POINT_set_affine_coordinates_GF2m(key->group, point, - x, y, ctx)) - goto err; - if (!EC_POINT_get_affine_coordinates_GF2m(key->group, point, - tx, ty, ctx)) - goto err; - } else -#endif - { - if (!EC_POINT_set_affine_coordinates_GFp(key->group, point, - x, y, ctx)) - goto err; - if (!EC_POINT_get_affine_coordinates_GFp(key->group, point, - tx, ty, ctx)) - goto err; - } /* - * Check if retrieved coordinates match originals and are less than field - * order: if not values are out of range. + * Check if retrieved coordinates match originals. The range check is done + * inside EC_KEY_check_key(). */ - if (BN_cmp(x, tx) || BN_cmp(y, ty) - || (BN_cmp(x, key->group->field) >= 0) - || (BN_cmp(y, key->group->field) >= 0)) { + if (BN_cmp(x, tx) || BN_cmp(y, ty)) { ECerr(EC_F_EC_KEY_SET_PUBLIC_KEY_AFFINE_COORDINATES, EC_R_COORDINATES_OUT_OF_RANGE); goto err; } + /* EC_KEY_set_public_key updates dirty_cnt */ if (!EC_KEY_set_public_key(key, point)) goto err; @@ -431,12 +620,18 @@ int EC_KEY_set_public_key_affine_coordinates(EC_KEY *key, BIGNUM *x, ok = 1; err: + BN_CTX_end(ctx); BN_CTX_free(ctx); EC_POINT_free(point); return ok; } +OPENSSL_CTX *ec_key_get_libctx(const EC_KEY *key) +{ + return key->libctx; +} + const EC_GROUP *EC_KEY_get0_group(const EC_KEY *key) { return key->group; @@ -448,6 +643,7 @@ int EC_KEY_set_group(EC_KEY *key, const EC_GROUP *group) return 0; EC_GROUP_free(key->group); key->group = EC_GROUP_dup(group); + key->dirty_cnt++; return (key->group == NULL) ? 0 : 1; } @@ -458,12 +654,87 @@ const BIGNUM *EC_KEY_get0_private_key(const EC_KEY *key) int EC_KEY_set_private_key(EC_KEY *key, const BIGNUM *priv_key) { + int fixed_top; + const BIGNUM *order = NULL; + BIGNUM *tmp_key = NULL; + + if (key->group == NULL || key->group->meth == NULL) + return 0; + + /* + * Not only should key->group be set, but it should also be in a valid + * fully initialized state. + * + * Specifically, to operate in constant time, we need that the group order + * is set, as we use its length as the fixed public size of any scalar used + * as an EC private key. + */ + order = EC_GROUP_get0_order(key->group); + if (order == NULL || BN_is_zero(order)) + return 0; /* This should never happen */ + + if (key->group->meth->set_private != NULL + && key->group->meth->set_private(key, priv_key) == 0) + return 0; if (key->meth->set_private != NULL && key->meth->set_private(key, priv_key) == 0) return 0; + + /* + * We should never leak the bit length of the secret scalar in the key, + * so we always set the `BN_FLG_CONSTTIME` flag on the internal `BIGNUM` + * holding the secret scalar. + * + * This is important also because `BN_dup()` (and `BN_copy()`) do not + * propagate the `BN_FLG_CONSTTIME` flag from the source `BIGNUM`, and + * this brings an extra risk of inadvertently losing the flag, even when + * the caller specifically set it. + * + * The propagation has been turned on and off a few times in the past + * years because in some conditions has shown unintended consequences in + * some code paths, so at the moment we can't fix this in the BN layer. + * + * In `EC_KEY_set_private_key()` we can work around the propagation by + * manually setting the flag after `BN_dup()` as we know for sure that + * inside the EC module the `BN_FLG_CONSTTIME` is always treated + * correctly and should not generate unintended consequences. + * + * Setting the BN_FLG_CONSTTIME flag alone is never enough, we also have + * to preallocate the BIGNUM internal buffer to a fixed public size big + * enough that operations performed during the processing never trigger + * a realloc which would leak the size of the scalar through memory + * accesses. + * + * Fixed Length + * ------------ + * + * The order of the large prime subgroup of the curve is our choice for + * a fixed public size, as that is generally the upper bound for + * generating a private key in EC cryptosystems and should fit all valid + * secret scalars. + * + * For preallocating the BIGNUM storage we look at the number of "words" + * required for the internal representation of the order, and we + * preallocate 2 extra "words" in case any of the subsequent processing + * might temporarily overflow the order length. + */ + tmp_key = BN_dup(priv_key); + if (tmp_key == NULL) + return 0; + + BN_set_flags(tmp_key, BN_FLG_CONSTTIME); + + fixed_top = bn_get_top(order) + 2; + if (bn_wexpand(tmp_key, fixed_top) == NULL) { + BN_clear_free(tmp_key); + return 0; + } + BN_clear_free(key->priv_key); - key->priv_key = BN_dup(priv_key); - return (key->priv_key == NULL) ? 0 : 1; + key->priv_key = tmp_key; + key->dirty_cnt++; + + return 1; } const EC_POINT *EC_KEY_get0_public_key(const EC_KEY *key) @@ -478,6 +749,7 @@ int EC_KEY_set_public_key(EC_KEY *key, const EC_POINT *pub_key) return 0; EC_POINT_free(key->pub_key); key->pub_key = EC_POINT_dup(pub_key, key->group); + key->dirty_cnt++; return (key->pub_key == NULL) ? 0 : 1; } @@ -509,12 +781,14 @@ void EC_KEY_set_asn1_flag(EC_KEY *key, int flag) EC_GROUP_set_asn1_flag(key->group, flag); } +#ifndef OPENSSL_NO_DEPRECATED_3_0 int EC_KEY_precompute_mult(EC_KEY *key, BN_CTX *ctx) { if (key->group == NULL) return 0; return EC_GROUP_precompute_mult(key->group, ctx); } +#endif int EC_KEY_get_flags(const EC_KEY *key) { @@ -524,11 +798,13 @@ int EC_KEY_get_flags(const EC_KEY *key) void EC_KEY_set_flags(EC_KEY *key, int flags) { key->flags |= flags; + key->dirty_cnt++; } void EC_KEY_clear_flags(EC_KEY *key, int flags) { key->flags &= ~flags; + key->dirty_cnt++; } size_t EC_KEY_key2buf(const EC_KEY *key, point_conversion_form_t form, @@ -548,5 +824,157 @@ int EC_KEY_oct2key(EC_KEY *key, const unsigned char *buf, size_t len, key->pub_key = EC_POINT_new(key->group); if (key->pub_key == NULL) return 0; - return EC_POINT_oct2point(key->group, key->pub_key, buf, len, ctx); + if (EC_POINT_oct2point(key->group, key->pub_key, buf, len, ctx) == 0) + return 0; + key->dirty_cnt++; + /* + * Save the point conversion form. + * For non-custom curves the first octet of the buffer (excluding + * the last significant bit) contains the point conversion form. + * EC_POINT_oct2point() has already performed sanity checking of + * the buffer so we know it is valid. + */ + if ((key->group->meth->flags & EC_FLAGS_CUSTOM_CURVE) == 0) + key->conv_form = (point_conversion_form_t)(buf[0] & ~0x01); + return 1; +} + +size_t EC_KEY_priv2oct(const EC_KEY *eckey, + unsigned char *buf, size_t len) +{ + if (eckey->group == NULL || eckey->group->meth == NULL) + return 0; + if (eckey->group->meth->priv2oct == NULL) { + ECerr(EC_F_EC_KEY_PRIV2OCT, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED); + return 0; + } + + return eckey->group->meth->priv2oct(eckey, buf, len); +} + +size_t ec_key_simple_priv2oct(const EC_KEY *eckey, + unsigned char *buf, size_t len) +{ + size_t buf_len; + + buf_len = (EC_GROUP_order_bits(eckey->group) + 7) / 8; + if (eckey->priv_key == NULL) + return 0; + if (buf == NULL) + return buf_len; + else if (len < buf_len) + return 0; + + /* Octetstring may need leading zeros if BN is to short */ + + if (BN_bn2binpad(eckey->priv_key, buf, buf_len) == -1) { + ECerr(EC_F_EC_KEY_SIMPLE_PRIV2OCT, EC_R_BUFFER_TOO_SMALL); + return 0; + } + + return buf_len; +} + +int EC_KEY_oct2priv(EC_KEY *eckey, const unsigned char *buf, size_t len) +{ + int ret; + + if (eckey->group == NULL || eckey->group->meth == NULL) + return 0; + if (eckey->group->meth->oct2priv == NULL) { + ECerr(EC_F_EC_KEY_OCT2PRIV, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED); + return 0; + } + ret = eckey->group->meth->oct2priv(eckey, buf, len); + if (ret == 1) + eckey->dirty_cnt++; + return ret; +} + +int ec_key_simple_oct2priv(EC_KEY *eckey, const unsigned char *buf, size_t len) +{ + if (eckey->priv_key == NULL) + eckey->priv_key = BN_secure_new(); + if (eckey->priv_key == NULL) { + ECerr(EC_F_EC_KEY_SIMPLE_OCT2PRIV, ERR_R_MALLOC_FAILURE); + return 0; + } + eckey->priv_key = BN_bin2bn(buf, len, eckey->priv_key); + if (eckey->priv_key == NULL) { + ECerr(EC_F_EC_KEY_SIMPLE_OCT2PRIV, ERR_R_BN_LIB); + return 0; + } + eckey->dirty_cnt++; + return 1; +} + +size_t EC_KEY_priv2buf(const EC_KEY *eckey, unsigned char **pbuf) +{ + size_t len; + unsigned char *buf; + + len = EC_KEY_priv2oct(eckey, NULL, 0); + if (len == 0) + return 0; + if ((buf = OPENSSL_malloc(len)) == NULL) { + ECerr(EC_F_EC_KEY_PRIV2BUF, ERR_R_MALLOC_FAILURE); + return 0; + } + len = EC_KEY_priv2oct(eckey, buf, len); + if (len == 0) { + OPENSSL_free(buf); + return 0; + } + *pbuf = buf; + return len; +} + +int EC_KEY_can_sign(const EC_KEY *eckey) +{ + if (eckey->group == NULL || eckey->group->meth == NULL + || (eckey->group->meth->flags & EC_FLAGS_NO_SIGN)) + return 0; + return 1; +} + +/* + * FIPS 140-2 IG 9.9 AS09.33 + * Perform a sign/verify operation. + * + * NOTE: When generating keys for key-agreement schemes - FIPS 140-2 IG 9.9 + * states that no additional pairwise tests are required (apart from the tests + * specified in SP800-56A) when generating keys. Hence pairwise ECDH tests are + * omitted here. + */ +static int ecdsa_keygen_pairwise_test(EC_KEY *eckey, OSSL_CALLBACK *cb, + void *cbarg) +{ + int ret = 0; + unsigned char dgst[16] = {0}; + int dgst_len = (int)sizeof(dgst); + ECDSA_SIG *sig = NULL; + OSSL_SELF_TEST *st = NULL; + + st = OSSL_SELF_TEST_new(cb, cbarg); + if (st == NULL) + return 0; + + OSSL_SELF_TEST_onbegin(st, OSSL_SELF_TEST_TYPE_PCT, + OSSL_SELF_TEST_DESC_PCT_ECDSA); + + sig = ECDSA_do_sign(dgst, dgst_len, eckey); + if (sig == NULL) + goto err; + + OSSL_SELF_TEST_oncorrupt_byte(st, dgst); + + if (ECDSA_do_verify(dgst, dgst_len, sig, eckey) != 1) + goto err; + + ret = 1; +err: + OSSL_SELF_TEST_onend(st, ret); + OSSL_SELF_TEST_free(st); + ECDSA_SIG_free(sig); + return ret; }