dh_pmeth.c
/*
* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project
* 2006.
*/
/* ====================================================================
* Copyright (c) 2006 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
* licensing@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).
*
*/
#include <stdio.h>
#include "cryptlib.h"
#include <openssl/asn1t.h>
#include <openssl/x509.h>
#include <openssl/evp.h>
#include <openssl/dh.h>
#include <openssl/bn.h>
#include "evp_locl.h"
/* DH pkey context structure */
typedef struct {
/* Parameter gen parameters */
int prime_len;
int generator;
int use_dsa;
/* Keygen callback info */
int gentmp[2];
/* message digest */
} DH_PKEY_CTX;
static int pkey_dh_init(EVP_PKEY_CTX *ctx)
{
DH_PKEY_CTX *dctx;
dctx = OPENSSL_malloc(sizeof(DH_PKEY_CTX));
if (!dctx)
return 0;
dctx->prime_len = 1024;
dctx->generator = 2;
dctx->use_dsa = 0;
ctx->data = dctx;
ctx->keygen_info = dctx->gentmp;
ctx->keygen_info_count = 2;
return 1;
}
static int pkey_dh_copy(EVP_PKEY_CTX *dst, EVP_PKEY_CTX *src)
{
DH_PKEY_CTX *dctx, *sctx;
if (!pkey_dh_init(dst))
return 0;
sctx = src->data;
dctx = dst->data;
dctx->prime_len = sctx->prime_len;
dctx->generator = sctx->generator;
dctx->use_dsa = sctx->use_dsa;
return 1;
}
static void pkey_dh_cleanup(EVP_PKEY_CTX *ctx)
{
DH_PKEY_CTX *dctx = ctx->data;
if (dctx)
OPENSSL_free(dctx);
}
static int pkey_dh_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2)
{
DH_PKEY_CTX *dctx = ctx->data;
switch (type) {
case EVP_PKEY_CTRL_DH_PARAMGEN_PRIME_LEN:
if (p1 < 256)
return -2;
dctx->prime_len = p1;
return 1;
case EVP_PKEY_CTRL_DH_PARAMGEN_GENERATOR:
dctx->generator = p1;
return 1;
case EVP_PKEY_CTRL_PEER_KEY:
/* Default behaviour is OK */
return 1;
default:
return -2;
}
}
static int pkey_dh_ctrl_str(EVP_PKEY_CTX *ctx,
const char *type, const char *value)
{
if (!strcmp(type, "dh_paramgen_prime_len")) {
int len;
len = atoi(value);
return EVP_PKEY_CTX_set_dh_paramgen_prime_len(ctx, len);
}
if (!strcmp(type, "dh_paramgen_generator")) {
int len;
len = atoi(value);
return EVP_PKEY_CTX_set_dh_paramgen_generator(ctx, len);
}
return -2;
}
static int pkey_dh_paramgen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
{
DH *dh = NULL;
DH_PKEY_CTX *dctx = ctx->data;
BN_GENCB *pcb, cb;
int ret;
if (ctx->pkey_gencb) {
pcb = &cb;
evp_pkey_set_cb_translate(pcb, ctx);
} else
pcb = NULL;
dh = DH_new();
if (!dh)
return 0;
ret = DH_generate_parameters_ex(dh,
dctx->prime_len, dctx->generator, pcb);
if (ret)
EVP_PKEY_assign_DH(pkey, dh);
else
DH_free(dh);
return ret;
}
static int pkey_dh_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
{
DH *dh = NULL;
if (ctx->pkey == NULL) {
DHerr(DH_F_PKEY_DH_KEYGEN, DH_R_NO_PARAMETERS_SET);
return 0;
}
dh = DH_new();
if (!dh)
return 0;
EVP_PKEY_assign_DH(pkey, dh);
/* Note: if error return, pkey is freed by parent routine */
if (!EVP_PKEY_copy_parameters(pkey, ctx->pkey))
return 0;
return DH_generate_key(pkey->pkey.dh);
}
static int pkey_dh_derive(EVP_PKEY_CTX *ctx, unsigned char *key,
size_t *keylen)
{
int ret;
if (!ctx->pkey || !ctx->peerkey) {
DHerr(DH_F_PKEY_DH_DERIVE, DH_R_KEYS_NOT_SET);
return 0;
}
ret = DH_compute_key(key, ctx->peerkey->pkey.dh->pub_key,
ctx->pkey->pkey.dh);
if (ret < 0)
return ret;
*keylen = ret;
return 1;
}
const EVP_PKEY_METHOD dh_pkey_meth = {
EVP_PKEY_DH,
EVP_PKEY_FLAG_AUTOARGLEN,
pkey_dh_init,
pkey_dh_copy,
pkey_dh_cleanup,
0,
pkey_dh_paramgen,
0,
pkey_dh_keygen,
0,
0,
0,
0,
0, 0,
0, 0, 0, 0,
0, 0,
0, 0,
0,
pkey_dh_derive,
pkey_dh_ctrl,
pkey_dh_ctrl_str
};
