openssl/crypto/dh/dh_asn1.c
Pauli ada66e78ef Deprecate the low level Diffie-Hellman functions.
Use of the low level DH functions has been informally discouraged for a
long time.  We now formally deprecate them.

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/11024)
2020-02-20 19:04:57 +10:00

161 lines
4.5 KiB
C

/*
* Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the Apache License 2.0 (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
*/
/*
* DH low level APIs are deprecated for public use, but still ok for
* internal use.
*/
#include "internal/deprecated.h"
#include <stdio.h>
#include "internal/cryptlib.h"
#include <openssl/bn.h>
#include "dh_local.h"
#include <openssl/objects.h>
#include <openssl/asn1t.h>
/* Override the default free and new methods */
static int dh_cb(int operation, ASN1_VALUE **pval, const ASN1_ITEM *it,
void *exarg)
{
if (operation == ASN1_OP_NEW_PRE) {
*pval = (ASN1_VALUE *)DH_new();
if (*pval != NULL)
return 2;
return 0;
} else if (operation == ASN1_OP_FREE_PRE) {
DH_free((DH *)*pval);
*pval = NULL;
return 2;
} else if (operation == ASN1_OP_D2I_POST) {
((DH *)*pval)->dirty_cnt++;
}
return 1;
}
ASN1_SEQUENCE_cb(DHparams, dh_cb) = {
ASN1_SIMPLE(DH, params.p, BIGNUM),
ASN1_SIMPLE(DH, params.g, BIGNUM),
ASN1_OPT_EMBED(DH, length, ZINT32),
} ASN1_SEQUENCE_END_cb(DH, DHparams)
IMPLEMENT_ASN1_ENCODE_FUNCTIONS_fname(DH, DHparams, DHparams)
/*
* Internal only structures for handling X9.42 DH: this gets translated to or
* from a DH structure straight away.
*/
typedef struct {
ASN1_BIT_STRING *seed;
BIGNUM *counter;
} int_dhvparams;
typedef struct {
BIGNUM *p;
BIGNUM *q;
BIGNUM *g;
BIGNUM *j;
int_dhvparams *vparams;
} int_dhx942_dh;
ASN1_SEQUENCE(DHvparams) = {
ASN1_SIMPLE(int_dhvparams, seed, ASN1_BIT_STRING),
ASN1_SIMPLE(int_dhvparams, counter, BIGNUM)
} static_ASN1_SEQUENCE_END_name(int_dhvparams, DHvparams)
ASN1_SEQUENCE(DHxparams) = {
ASN1_SIMPLE(int_dhx942_dh, p, BIGNUM),
ASN1_SIMPLE(int_dhx942_dh, g, BIGNUM),
ASN1_SIMPLE(int_dhx942_dh, q, BIGNUM),
ASN1_OPT(int_dhx942_dh, j, BIGNUM),
ASN1_OPT(int_dhx942_dh, vparams, DHvparams),
} static_ASN1_SEQUENCE_END_name(int_dhx942_dh, DHxparams)
int_dhx942_dh *d2i_int_dhx(int_dhx942_dh **a,
const unsigned char **pp, long length);
int i2d_int_dhx(const int_dhx942_dh *a, unsigned char **pp);
IMPLEMENT_ASN1_ENCODE_FUNCTIONS_fname(int_dhx942_dh, DHxparams, int_dhx)
/* Application public function: read in X9.42 DH parameters into DH structure */
DH *d2i_DHxparams(DH **a, const unsigned char **pp, long length)
{
FFC_PARAMS *params;
int_dhx942_dh *dhx = NULL;
DH *dh = NULL;
dh = DH_new();
if (dh == NULL)
return NULL;
dhx = d2i_int_dhx(NULL, pp, length);
if (dhx == NULL) {
DH_free(dh);
return NULL;
}
if (a != NULL) {
DH_free(*a);
*a = dh;
}
params = &dh->params;
DH_set0_pqg(dh, dhx->p, dhx->q, dhx->g);
ffc_params_set0_j(params, dhx->j);
if (dhx->vparams != NULL) {
/* The counter has a maximum value of 4 * numbits(p) - 1 */
size_t counter = (size_t)BN_get_word(dhx->vparams->counter);
ffc_params_set_validate_params(params, dhx->vparams->seed->data,
dhx->vparams->seed->length, counter);
ASN1_BIT_STRING_free(dhx->vparams->seed);
BN_free(dhx->vparams->counter);
OPENSSL_free(dhx->vparams);
dhx->vparams = NULL;
}
OPENSSL_free(dhx);
return dh;
}
int i2d_DHxparams(const DH *dh, unsigned char **pp)
{
int ret = 0;
int_dhx942_dh dhx;
int_dhvparams dhv = { NULL, NULL };
ASN1_BIT_STRING seed;
size_t seedlen = 0;
const FFC_PARAMS *params = &dh->params;
int counter;
ffc_params_get0_pqg(params, (const BIGNUM **)&dhx.p,
(const BIGNUM **)&dhx.q, (const BIGNUM **)&dhx.g);
dhx.j = params->j;
ffc_params_get_validate_params(params, &seed.data, &seedlen, &counter);
seed.length = (int)seedlen;
if (counter != -1 && seed.data != NULL && seed.length > 0) {
seed.flags = ASN1_STRING_FLAG_BITS_LEFT;
dhv.seed = &seed;
dhv.counter = BN_new();
if (dhv.counter == NULL)
return 0;
if (!BN_set_word(dhv.counter, (BN_ULONG)counter))
goto err;
dhx.vparams = &dhv;
} else {
dhx.vparams = NULL;
}
ret = i2d_int_dhx(&dhx, pp);
err:
BN_free(dhv.counter);
return ret;
}