| /* |
| * Elliptic curve Diffie-Hellman |
| * |
| * Copyright (C) 2006-2013, Brainspark B.V. |
| * |
| * This file is part of PolarSSL (http://www.polarssl.org) |
| * Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org> |
| * |
| * All rights reserved. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License along |
| * with this program; if not, write to the Free Software Foundation, Inc., |
| * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| */ |
| |
| /* |
| * References: |
| * |
| * SEC1 http://www.secg.org/index.php?action=secg,docs_secg |
| */ |
| |
| #include "polarssl/config.h" |
| |
| #if defined(POLARSSL_ECP_C) |
| |
| #include "polarssl/ecdh.h" |
| |
| /* |
| * Generate public key: simple wrapper around ecp_gen_keypair |
| */ |
| int ecdh_gen_public( const ecp_group *grp, mpi *d, ecp_point *Q, |
| int (*f_rng)(void *, unsigned char *, size_t), |
| void *p_rng ) |
| { |
| return ecp_gen_keypair( grp, d, Q, f_rng, p_rng ); |
| } |
| |
| /* |
| * Compute shared secret (SEC1 3.3.1) |
| */ |
| int ecdh_compute_shared( const ecp_group *grp, mpi *z, |
| const ecp_point *Q, const mpi *d ) |
| { |
| int ret; |
| ecp_point P; |
| |
| ecp_point_init( &P ); |
| |
| /* |
| * Make sure Q is a valid pubkey before using it |
| */ |
| MPI_CHK( ecp_check_pubkey( grp, Q ) ); |
| |
| MPI_CHK( ecp_mul( grp, &P, d, Q ) ); |
| |
| if( ecp_is_zero( &P ) ) |
| return( POLARSSL_ERR_ECP_BAD_INPUT_DATA ); |
| |
| MPI_CHK( mpi_copy( z, &P.X ) ); |
| |
| cleanup: |
| ecp_point_free( &P ); |
| |
| return( ret ); |
| } |
| |
| |
| #if defined(POLARSSL_SELF_TEST) |
| |
| /* |
| * Checkup routine |
| */ |
| int ecdh_self_test( int verbose ) |
| { |
| return( verbose++ ); |
| } |
| |
| #endif |
| |
| #endif /* defined(POLARSSL_ECP_C) */ |