/*      $OpenBSD: ec_kmeth.c,v 1.6 2021/12/04 16:08:32 tb Exp $ */
/*
 * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
 * project.
 */
/* ====================================================================
 * Copyright (c) 2015 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.
 * ====================================================================
 */

#include <openssl/ec.h>
#ifndef OPENSSL_NO_ENGINE
#include <openssl/engine.h>
#endif
#include <openssl/err.h>

#include "bn_lcl.h"
#include "ec_lcl.h"
#include "ecs_locl.h"

static const EC_KEY_METHOD openssl_ec_key_method = {
        .name = "OpenSSL EC_KEY method",
        .flags = 0,

        .init = NULL,
        .finish = NULL,
        .copy = NULL,

        .set_group = NULL,
        .set_private = NULL,
        .set_public = NULL,

        .keygen = ossl_ec_key_gen,
        .compute_key = ossl_ecdh_compute_key,

        .sign = ossl_ecdsa_sign,
        .sign_setup = ossl_ecdsa_sign_setup,
        .sign_sig = ossl_ecdsa_sign_sig,

        .verify = ossl_ecdsa_verify,
        .verify_sig = ossl_ecdsa_verify_sig,
};

const EC_KEY_METHOD *default_ec_key_meth = &openssl_ec_key_method;

const EC_KEY_METHOD *
EC_KEY_OpenSSL(void)
{
        return &openssl_ec_key_method;
}

const EC_KEY_METHOD *
EC_KEY_get_default_method(void)
{
        return default_ec_key_meth;
}

void
EC_KEY_set_default_method(const EC_KEY_METHOD *meth)
{
        if (meth == NULL)
                default_ec_key_meth = &openssl_ec_key_method;
        else
                default_ec_key_meth = meth;
}

const EC_KEY_METHOD *
EC_KEY_get_method(const EC_KEY *key)
{
        return key->meth;
}

int
EC_KEY_set_method(EC_KEY *key, const EC_KEY_METHOD *meth)
{
        void (*finish)(EC_KEY *key) = key->meth->finish;

        if (finish != NULL)
                finish(key);

#ifndef OPENSSL_NO_ENGINE
        ENGINE_finish(key->engine);
        key->engine = NULL;
#endif

        key->meth = meth;
        if (meth->init != NULL)
                return meth->init(key);
        return 1;
}

EC_KEY *
EC_KEY_new_method(ENGINE *engine)
{
        EC_KEY *ret;

        if ((ret = calloc(1, sizeof(EC_KEY))) == NULL) {
                ECerror(ERR_R_MALLOC_FAILURE);
                return NULL;
        }
        ret->meth = EC_KEY_get_default_method();
#ifndef OPENSSL_NO_ENGINE
        if (engine != NULL) {
                if (!ENGINE_init(engine)) {
                        ECerror(ERR_R_ENGINE_LIB);
                        goto err;
                }
                ret->engine = engine;
        } else
                ret->engine = ENGINE_get_default_EC();
        if (ret->engine) {
                ret->meth = ENGINE_get_EC(ret->engine);
                if (ret->meth == NULL) {
                        ECerror(ERR_R_ENGINE_LIB);
                        goto err;
                }
        }
#endif
        ret->version = 1;
        ret->flags = 0;
        ret->group = NULL;
        ret->pub_key = NULL;
        ret->priv_key = NULL;
        ret->enc_flag = 0;
        ret->conv_form = POINT_CONVERSION_UNCOMPRESSED;
        ret->references = 1;
        ret->method_data = NULL;

        if (!CRYPTO_new_ex_data(CRYPTO_EX_INDEX_RSA, ret, &ret->ex_data))
                goto err;
        if (ret->meth->init != NULL && ret->meth->init(ret) == 0)
                goto err;

        return ret;

 err:
        EC_KEY_free(ret);
        return NULL;
}

EC_KEY_METHOD *
EC_KEY_METHOD_new(const EC_KEY_METHOD *meth)
{
        EC_KEY_METHOD *ret;

        if ((ret = calloc(1, sizeof(*meth))) == NULL)
                return NULL;
        if (meth != NULL)
                *ret = *meth;
        ret->flags |= EC_KEY_METHOD_DYNAMIC;
        return ret;
}

void
EC_KEY_METHOD_free(EC_KEY_METHOD *meth)
{
        if (meth == NULL)
                return;
        if (meth->flags & EC_KEY_METHOD_DYNAMIC)
                free(meth);
}

void
EC_KEY_METHOD_set_init(EC_KEY_METHOD *meth,
    int (*init)(EC_KEY *key),
    void (*finish)(EC_KEY *key),
    int (*copy)(EC_KEY *dest, const EC_KEY *src),
    int (*set_group)(EC_KEY *key, const EC_GROUP *grp),
    int (*set_private)(EC_KEY *key, const BIGNUM *priv_key),
    int (*set_public)(EC_KEY *key, const EC_POINT *pub_key))
{
        meth->init = init;
        meth->finish = finish;
        meth->copy = copy;
        meth->set_group = set_group;
        meth->set_private = set_private;
        meth->set_public = set_public;
}

void
EC_KEY_METHOD_set_keygen(EC_KEY_METHOD *meth, int (*keygen)(EC_KEY *key))
{
        meth->keygen = keygen;
}

void
EC_KEY_METHOD_set_compute_key(EC_KEY_METHOD *meth,
   int (*ckey)(void *out, size_t outlen, const EC_POINT *pub_key, EC_KEY *ecdh,
   void *(*KDF) (const void *in, size_t inlen, void *out, size_t *outlen)))
{
        meth->compute_key = ckey;
}

void
EC_KEY_METHOD_set_sign(EC_KEY_METHOD *meth,
    int (*sign)(int type, const unsigned char *dgst,
        int dlen, unsigned char *sig, unsigned int *siglen,
        const BIGNUM *kinv, const BIGNUM *r, EC_KEY *eckey),
    int (*sign_setup)(EC_KEY *eckey, BN_CTX *ctx_in,
        BIGNUM **kinvp, BIGNUM **rp),
    ECDSA_SIG *(*sign_sig)(const unsigned char *dgst,
        int dgst_len, const BIGNUM *in_kinv,
        const BIGNUM *in_r, EC_KEY *eckey))
{
        meth->sign = sign;
        meth->sign_setup = sign_setup;
        meth->sign_sig = sign_sig;
}

void
EC_KEY_METHOD_set_verify(EC_KEY_METHOD *meth,
    int (*verify)(int type, const unsigned char *dgst, int dgst_len,
        const unsigned char *sigbuf, int sig_len, EC_KEY *eckey),
    int (*verify_sig)(const unsigned char *dgst, int dgst_len,
        const ECDSA_SIG *sig, EC_KEY *eckey))
{
        meth->verify = verify;
        meth->verify_sig = verify_sig;
}


void
EC_KEY_METHOD_get_init(const EC_KEY_METHOD *meth,
    int (**pinit)(EC_KEY *key),
    void (**pfinish)(EC_KEY *key),
    int (**pcopy)(EC_KEY *dest, const EC_KEY *src),
    int (**pset_group)(EC_KEY *key, const EC_GROUP *grp),
    int (**pset_private)(EC_KEY *key, const BIGNUM *priv_key),
    int (**pset_public)(EC_KEY *key, const EC_POINT *pub_key))
{
        if (pinit != NULL)
                *pinit = meth->init;
        if (pfinish != NULL)
                *pfinish = meth->finish;
        if (pcopy != NULL)
                *pcopy = meth->copy;
        if (pset_group != NULL)
                *pset_group = meth->set_group;
        if (pset_private != NULL)
                *pset_private = meth->set_private;
        if (pset_public != NULL)
                *pset_public = meth->set_public;
}

void
EC_KEY_METHOD_get_keygen(const EC_KEY_METHOD *meth,
    int (**pkeygen)(EC_KEY *key))
{
        if (pkeygen != NULL)
                *pkeygen = meth->keygen;
}

void
EC_KEY_METHOD_get_compute_key(const EC_KEY_METHOD *meth,
    int (**pck)(void *out, size_t outlen, const EC_POINT *pub_key, EC_KEY *ecdh,
    void *(*KDF) (const void *in, size_t inlen, void *out, size_t *outlen)))
{
        if (pck != NULL)
                *pck = meth->compute_key;
}

void
EC_KEY_METHOD_get_sign(const EC_KEY_METHOD *meth,
    int (**psign)(int type, const unsigned char *dgst,
        int dlen, unsigned char *sig, unsigned int *siglen,
        const BIGNUM *kinv, const BIGNUM *r, EC_KEY *eckey),
    int (**psign_setup)(EC_KEY *eckey, BN_CTX *ctx_in,
        BIGNUM **kinvp, BIGNUM **rp),
    ECDSA_SIG *(**psign_sig)(const unsigned char *dgst,
        int dgst_len, const BIGNUM *in_kinv, const BIGNUM *in_r,
        EC_KEY *eckey))
{
        if (psign != NULL)
                *psign = meth->sign;
        if (psign_setup != NULL)
                *psign_setup = meth->sign_setup;
        if (psign_sig != NULL)
                *psign_sig = meth->sign_sig;
}

void
EC_KEY_METHOD_get_verify(const EC_KEY_METHOD *meth,
    int (**pverify)(int type, const unsigned char *dgst, int dgst_len,
        const unsigned char *sigbuf, int sig_len, EC_KEY *eckey),
    int (**pverify_sig)(const unsigned char *dgst, int dgst_len,
        const ECDSA_SIG *sig, EC_KEY *eckey))
{
        if (pverify != NULL)
                *pverify = meth->verify;
        if (pverify_sig != NULL)
                *pverify_sig = meth->verify_sig;
}