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>
#ifndef OPENSSL_NO_DSA
#include <openssl/dsa.h>
#endif
#include <openssl/objects.h>
#include "evp_locl.h"
/* DH pkey context structure */
typedef struct
{
/* Parameter gen parameters */
int prime_len;
int generator;
int use_dsa;
int subprime_len;
/* message digest used for parameter generation */
const EVP_MD *md;
int rfc5114_param;
/* Keygen callback info */
int gentmp[2];
/* KDF (if any) to use for DH */
char kdf_type;
/* OID to use for KDF */
ASN1_OBJECT *kdf_oid;
/* Message digest to use for key derivation */
const EVP_MD *kdf_md;
/* User key material */
unsigned char *kdf_ukm;
size_t kdf_ukmlen;
/* KDF output length */
size_t kdf_outlen;
} 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->subprime_len = -1;
dctx->generator = 2;
dctx->use_dsa = 0;
dctx->md = NULL;
dctx->rfc5114_param = 0;
dctx->kdf_type = EVP_PKEY_DH_KDF_NONE;
dctx->kdf_oid = NULL;
dctx->kdf_md = NULL;
dctx->kdf_ukm = NULL;
dctx->kdf_ukmlen = 0;
dctx->kdf_outlen = 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->subprime_len = sctx->subprime_len;
dctx->generator = sctx->generator;
dctx->use_dsa = sctx->use_dsa;
dctx->md = sctx->md;
dctx->rfc5114_param = sctx->rfc5114_param;
dctx->kdf_type = sctx->kdf_type;
dctx->kdf_oid = OBJ_dup(sctx->kdf_oid);
if (!dctx->kdf_oid)
return 0;
dctx->kdf_md = sctx->kdf_md;
if (dctx->kdf_ukm)
{
dctx->kdf_ukm = BUF_memdup(sctx->kdf_ukm, sctx->kdf_ukmlen);
dctx->kdf_ukmlen = sctx->kdf_ukmlen;
}
dctx->kdf_outlen = sctx->kdf_outlen;
return 1;
}
static void pkey_dh_cleanup(EVP_PKEY_CTX *ctx)
{
DH_PKEY_CTX *dctx = ctx->data;
if (dctx)
{
if (dctx->kdf_ukm)
OPENSSL_free(dctx->kdf_ukm);
if (dctx->kdf_oid)
ASN1_OBJECT_free(dctx->kdf_oid);
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_SUBPRIME_LEN:
if (dctx->use_dsa == 0)
return -2;
dctx->subprime_len = p1;
return 1;
case EVP_PKEY_CTRL_DH_PARAMGEN_GENERATOR:
if (dctx->use_dsa)
return -2;
dctx->generator = p1;
return 1;
case EVP_PKEY_CTRL_DH_PARAMGEN_TYPE:
#ifdef OPENSSL_NO_DSA
if (p1 != 0)
return -2;
#else
if (p1 < 0 || p1 > 2)
return -2;
#endif
dctx->use_dsa = p1;
return 1;
case EVP_PKEY_CTRL_DH_RFC5114:
if (p1 < 1 || p1 > 3)
return -2;
dctx->rfc5114_param = p1;
return 1;
case EVP_PKEY_CTRL_PEER_KEY:
/* Default behaviour is OK */
return 1;
case EVP_PKEY_CTRL_DH_KDF_TYPE:
if (p1 == -2)
return dctx->kdf_type;
if (p1 != EVP_PKEY_DH_KDF_NONE &&
p1 != EVP_PKEY_DH_KDF_X9_42)
return -2;
dctx->kdf_type = p1;
return 1;
case EVP_PKEY_CTRL_DH_KDF_MD:
dctx->kdf_md = p2;
return 1;
case EVP_PKEY_CTRL_GET_DH_KDF_MD:
*(const EVP_MD **)p2 = dctx->kdf_md;
return 1;
case EVP_PKEY_CTRL_DH_KDF_OUTLEN:
if (p1 <= 0)
return -2;
dctx->kdf_outlen = (size_t)p1;
return 1;
case EVP_PKEY_CTRL_GET_DH_KDF_OUTLEN:
*(int *)p2 = dctx->kdf_outlen;
return 1;
case EVP_PKEY_CTRL_DH_KDF_UKM:
if (dctx->kdf_ukm)
OPENSSL_free(dctx->kdf_ukm);
dctx->kdf_ukm = p2;
if (p2)
dctx->kdf_ukmlen = p1;
else
dctx->kdf_ukmlen = 0;
return 1;
case EVP_PKEY_CTRL_GET_DH_KDF_UKM:
*(unsigned char **)p2 = dctx->kdf_ukm;
return dctx->kdf_ukmlen;
case EVP_PKEY_CTRL_DH_KDF_OID:
if (dctx->kdf_oid)
ASN1_OBJECT_free(dctx->kdf_oid);
dctx->kdf_oid = p2;
return 1;
case EVP_PKEY_CTRL_GET_DH_KDF_OID:
*(ASN1_OBJECT **)p2 = dctx->kdf_oid;
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_rfc5114"))
{
DH_PKEY_CTX *dctx = ctx->data;
int len;
len = atoi(value);
if (len < 0 || len > 3)
return -2;
dctx->rfc5114_param = len;
return 1;
}
if (!strcmp(type, "dh_paramgen_generator"))
{
int len;
len = atoi(value);
return EVP_PKEY_CTX_set_dh_paramgen_generator(ctx, len);
}
if (!strcmp(type, "dh_paramgen_subprime_len"))
{
int len;
len = atoi(value);
return EVP_PKEY_CTX_set_dh_paramgen_subprime_len(ctx, len);
}
if (!strcmp(type, "dh_paramgen_type"))
{
int typ;
typ = atoi(value);
return EVP_PKEY_CTX_set_dh_paramgen_type(ctx, typ);
}
return -2;
}
#ifndef OPENSSL_NO_DSA
extern int dsa_builtin_paramgen(DSA *ret, size_t bits, size_t qbits,
const EVP_MD *evpmd, const unsigned char *seed_in, size_t seed_len,
unsigned char *seed_out,
int *counter_ret, unsigned long *h_ret, BN_GENCB *cb);
extern int dsa_builtin_paramgen2(DSA *ret, size_t L, size_t N,
const EVP_MD *evpmd, const unsigned char *seed_in, size_t seed_len,
int idx, unsigned char *seed_out,
int *counter_ret, unsigned long *h_ret, BN_GENCB *cb);
static DSA *dsa_dh_generate(DH_PKEY_CTX *dctx, BN_GENCB *pcb)
{
DSA *ret;
int rv = 0;
int prime_len = dctx->prime_len;
int subprime_len = dctx->subprime_len;
const EVP_MD *md = dctx->md;
if (dctx->use_dsa > 2)
return NULL;
ret = DSA_new();
if (!ret)
return NULL;
if (subprime_len == -1)
{
if (prime_len >= 2048)
subprime_len = 256;
else
subprime_len = 160;
}
if (md == NULL)
{
if (prime_len >= 2048)
md = EVP_sha256();
else
md = EVP_sha1();
}
if (dctx->use_dsa == 1)
rv = dsa_builtin_paramgen(ret, prime_len, subprime_len, md,
NULL, 0, NULL, NULL, NULL, pcb);
else if(dctx->use_dsa == 2)
rv = dsa_builtin_paramgen2(ret, prime_len, subprime_len, md,
NULL, 0, -1, NULL, NULL, NULL, pcb);
if (rv <= 0)
{
DSA_free(ret);
return NULL;
}
return ret;
}
#endif
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 (dctx->rfc5114_param)
{
switch (dctx->rfc5114_param)
{
case 1:
dh = DH_get_1024_160();
break;
case 2:
dh = DH_get_2048_224();
break;
case 3:
dh = DH_get_2048_256();
break;
default:
return -2;
}
EVP_PKEY_assign(pkey, EVP_PKEY_DHX, dh);
return 1;
}
if (ctx->pkey_gencb)
{
pcb = &cb;
evp_pkey_set_cb_translate(pcb, ctx);
}
else
pcb = NULL;
#ifndef OPENSSL_NO_DSA
if (dctx->use_dsa)
{
DSA *dsa_dh;
dsa_dh = dsa_dh_generate(dctx, pcb);
if (!dsa_dh)
return 0;
dh = DSA_dup_DH(dsa_dh);
DSA_free(dsa_dh);
if (!dh)
return 0;
EVP_PKEY_assign(pkey, EVP_PKEY_DHX, dh);
return 1;
}
#endif
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(pkey, ctx->pmeth->pkey_id, 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;
DH *dh;
DH_PKEY_CTX *dctx = ctx->data;
BIGNUM *dhpub;
if (!ctx->pkey || !ctx->peerkey)
{
DHerr(DH_F_PKEY_DH_DERIVE, DH_R_KEYS_NOT_SET);
return 0;
}
dh = ctx->pkey->pkey.dh;
dhpub = ctx->peerkey->pkey.dh->pub_key;
if (dctx->kdf_type == EVP_PKEY_DH_KDF_NONE)
{
if (key == NULL)
{
*keylen = DH_size(dh);
return 1;
}
ret = DH_compute_key(key, dhpub, dh);
if (ret < 0)
return ret;
*keylen = ret;
return 1;
}
else if (dctx->kdf_type == EVP_PKEY_DH_KDF_X9_42)
{
unsigned char *Z = NULL;
size_t Zlen = 0;
if (!dctx->kdf_outlen || !dctx->kdf_oid)
return 0;
if (key == NULL)
{
*keylen = dctx->kdf_outlen;
return 1;
}
if (*keylen != dctx->kdf_outlen)
return 0;
ret = 0;
Zlen = DH_size(dh);
Z = OPENSSL_malloc(Zlen);
if (DH_compute_key_padded(Z, dhpub, dh) <= 0)
goto err;
if (!DH_KDF_X9_42(key, *keylen, Z, Zlen, dctx->kdf_oid,
dctx->kdf_ukm, dctx->kdf_ukmlen,
dctx->kdf_md))
goto err;
*keylen = dctx->kdf_outlen;
ret = 1;
err:
if (Z)
{
OPENSSL_cleanse(Z, Zlen);
OPENSSL_free(Z);
}
return ret;
}
return 1;
}
const EVP_PKEY_METHOD dh_pkey_meth =
{
EVP_PKEY_DH,
0,
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
};
const EVP_PKEY_METHOD dhx_pkey_meth =
{
EVP_PKEY_DHX,
0,
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
};
