Commit 5a212462 authored by Nicola Tuveri's avatar Nicola Tuveri Committed by Andy Polyakov
Browse files

Add inter-module private header for EC functions 



Internal submodules of libcrypto may require non-public functions from
the EC submodule.

In preparation to use `ec_group_do_inverse_ord()` (from #6116) inside
the SM2 submodule to apply a SCA mitigation on the modular inversion,
this commit moves the `ec_group_do_inverse_ord()` prototype declaration
from the EC-local `crypto/ec/ec_lcl.h` header to the
`crypto/include/internal/ec_int.h` inter-module private header.

Reviewed-by: default avatarAndy Polyakov <appro@openssl.org>
Reviewed-by: default avatarMatt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6521)
parent c35e9669

crypto/ec/ec_lcl.h

+1 −3
Original line number Diff line number Diff line
@@ -14,6 +14,7 @@ 
#include <openssl/ec.h>

#include <openssl/bn.h>

#include "internal/refcount.h"

#include "internal/ec_int.h"

#include "curve448/curve448_lcl.h"



#if defined(__SUNPRO_C)
@@ -636,7 +637,4 @@ int X25519(uint8_t out_shared_key[32], const uint8_t private_key[32], 
void X25519_public_from_private(uint8_t out_public_value[32],

                                const uint8_t private_key[32]);



int ec_group_do_inverse_ord(const EC_GROUP *group, BIGNUM *res,

                            const BIGNUM *x, BN_CTX *ctx);



int ec_point_blind_coordinates(const EC_GROUP *group, EC_POINT *p, BN_CTX *ctx);

crypto/include/internal/ec_int.h

0 → 100644
+45 −0
Original line number Diff line number Diff line 
/*

 * Copyright 2018 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the OpenSSL license (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

 */



/* Internal EC functions for other submodules: not for application use */



#ifndef HEADER_OSSL_EC_INTERNAL_H

# define HEADER_OSSL_EC_INTERNAL_H

# include <openssl/opensslconf.h>



# ifndef OPENSSL_NO_EC



#  include <openssl/ec.h>



/*-

 * Computes the multiplicative inverse of x in the range

 * [1,EC_GROUP::order), where EC_GROUP::order is the cardinality of the

 * subgroup generated by the generator G:

 *

 *         res := x^(-1) (mod EC_GROUP::order).

 *

 * This function expects the following two conditions to hold:

 *  - the EC_GROUP order is prime, and

 *  - x is included in the range [1, EC_GROUP::order).

 *

 * This function returns 1 on success, 0 on error.

 *

 * If the EC_GROUP order is even, this function explicitly returns 0 as

 * an error.

 * In case any of the two conditions stated above is not satisfied,

 * the correctness of its output is not guaranteed, even if the return

 * value could still be 1 (as primality testing and a conditional modular

 * reduction round on the input can be omitted by the underlying

 * implementations for better SCA properties on regular input values).

 */

__owur int ec_group_do_inverse_ord(const EC_GROUP *group, BIGNUM *res,

                                   const BIGNUM *x, BN_CTX *ctx);



# endif /* OPENSSL_NO_EC */

#endif