diff options
Diffstat (limited to 'openssl-1.1.0h/crypto/ec/ecdh_ossl.c')
| -rw-r--r-- | openssl-1.1.0h/crypto/ec/ecdh_ossl.c | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/openssl-1.1.0h/crypto/ec/ecdh_ossl.c b/openssl-1.1.0h/crypto/ec/ecdh_ossl.c new file mode 100644 index 0000000..a865145 --- /dev/null +++ b/openssl-1.1.0h/crypto/ec/ecdh_ossl.c @@ -0,0 +1,147 @@ +/* + * Copyright 2002-2016 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 + */ + +/* ==================================================================== + * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED. + * + * The Elliptic Curve Public-Key Crypto Library (ECC Code) included + * herein is developed by SUN MICROSYSTEMS, INC., and is contributed + * to the OpenSSL project. + * + * The ECC Code is licensed pursuant to the OpenSSL open source + * license provided below. + * + * The ECDH software is originally written by Douglas Stebila of + * Sun Microsystems Laboratories. + * + */ + +#include <string.h> +#include <limits.h> + +#include "internal/cryptlib.h" + +#include <openssl/err.h> +#include <openssl/bn.h> +#include <openssl/objects.h> +#include <openssl/ec.h> +#include "ec_lcl.h" + +int ossl_ecdh_compute_key(unsigned char **psec, size_t *pseclen, + const EC_POINT *pub_key, const EC_KEY *ecdh) +{ + if (ecdh->group->meth->ecdh_compute_key == NULL) { + ECerr(EC_F_OSSL_ECDH_COMPUTE_KEY, EC_R_CURVE_DOES_NOT_SUPPORT_ECDH); + return 0; + } + + return ecdh->group->meth->ecdh_compute_key(psec, pseclen, pub_key, ecdh); +} + +/*- + * This implementation is based on the following primitives in the IEEE 1363 standard: + * - ECKAS-DH1 + * - ECSVDP-DH + */ +int ecdh_simple_compute_key(unsigned char **pout, size_t *poutlen, + const EC_POINT *pub_key, const EC_KEY *ecdh) +{ + BN_CTX *ctx; + EC_POINT *tmp = NULL; + BIGNUM *x = NULL, *y = NULL; + const BIGNUM *priv_key; + const EC_GROUP *group; + int ret = 0; + size_t buflen, len; + unsigned char *buf = NULL; + + if ((ctx = BN_CTX_new()) == NULL) + goto err; + BN_CTX_start(ctx); + x = BN_CTX_get(ctx); + y = BN_CTX_get(ctx); + if (y == NULL) { + ECerr(EC_F_ECDH_SIMPLE_COMPUTE_KEY, ERR_R_MALLOC_FAILURE); + goto err; + } + + priv_key = EC_KEY_get0_private_key(ecdh); + if (priv_key == NULL) { + ECerr(EC_F_ECDH_SIMPLE_COMPUTE_KEY, EC_R_NO_PRIVATE_VALUE); + goto err; + } + + group = EC_KEY_get0_group(ecdh); + + if (EC_KEY_get_flags(ecdh) & EC_FLAG_COFACTOR_ECDH) { + if (!EC_GROUP_get_cofactor(group, x, NULL) || + !BN_mul(x, x, priv_key, ctx)) { + ECerr(EC_F_ECDH_SIMPLE_COMPUTE_KEY, ERR_R_MALLOC_FAILURE); + goto err; + } + priv_key = x; + } + + if ((tmp = EC_POINT_new(group)) == NULL) { + ECerr(EC_F_ECDH_SIMPLE_COMPUTE_KEY, ERR_R_MALLOC_FAILURE); + goto err; + } + + if (!EC_POINT_mul(group, tmp, NULL, pub_key, priv_key, ctx)) { + ECerr(EC_F_ECDH_SIMPLE_COMPUTE_KEY, EC_R_POINT_ARITHMETIC_FAILURE); + goto err; + } + + if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) == + NID_X9_62_prime_field) { + if (!EC_POINT_get_affine_coordinates_GFp(group, tmp, x, y, ctx)) { + ECerr(EC_F_ECDH_SIMPLE_COMPUTE_KEY, EC_R_POINT_ARITHMETIC_FAILURE); + goto err; + } + } +#ifndef OPENSSL_NO_EC2M + else { + if (!EC_POINT_get_affine_coordinates_GF2m(group, tmp, x, y, ctx)) { + ECerr(EC_F_ECDH_SIMPLE_COMPUTE_KEY, EC_R_POINT_ARITHMETIC_FAILURE); + goto err; + } + } +#endif + + buflen = (EC_GROUP_get_degree(group) + 7) / 8; + len = BN_num_bytes(x); + if (len > buflen) { + ECerr(EC_F_ECDH_SIMPLE_COMPUTE_KEY, ERR_R_INTERNAL_ERROR); + goto err; + } + if ((buf = OPENSSL_malloc(buflen)) == NULL) { + ECerr(EC_F_ECDH_SIMPLE_COMPUTE_KEY, ERR_R_MALLOC_FAILURE); + goto err; + } + + memset(buf, 0, buflen - len); + if (len != (size_t)BN_bn2bin(x, buf + buflen - len)) { + ECerr(EC_F_ECDH_SIMPLE_COMPUTE_KEY, ERR_R_BN_LIB); + goto err; + } + + *pout = buf; + *poutlen = buflen; + buf = NULL; + + ret = 1; + + err: + EC_POINT_free(tmp); + if (ctx) + BN_CTX_end(ctx); + BN_CTX_free(ctx); + OPENSSL_free(buf); + return ret; +} |