/* crypto/ec/ec_key.c */

/*

 * Written by Nils Larsch for the OpenSSL project.

 */

/* ====================================================================

 * Copyright (c) 1998-2005 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

 *    openssl-core@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).

 *

 */

/* ====================================================================

 * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.

 * Portions originally developed by SUN MICROSYSTEMS, INC., and

 * contributed to the OpenSSL project.

 */

#include <string.h>

#include "ec_lcl.h"

#include <openssl/err.h>

#ifdef OPENSSL_FIPS

# include <openssl/fips.h>

#endif

EC_KEY *EC_KEY_new(void)

{

    EC_KEY *ret;

    ret = (EC_KEY *)OPENSSL_malloc(sizeof(EC_KEY));

    if (ret == NULL) {

        ECerr(EC_F_EC_KEY_NEW, ERR_R_MALLOC_FAILURE);

        return (NULL);

    }

    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;

    return (ret);

}

EC_KEY *EC_KEY_new_by_curve_name(int nid)

{

    EC_KEY *ret = EC_KEY_new();

    if (ret == NULL)

        return NULL;

    ret->group = EC_GROUP_new_by_curve_name(nid);

    if (ret->group == NULL) {

        EC_KEY_free(ret);

        return NULL;

    }

    return ret;

}

void EC_KEY_free(EC_KEY *r)

{

    int i;

    if (r == NULL)

        return;

    i = CRYPTO_add(&r->references, -1, CRYPTO_LOCK_EC);

#ifdef REF_PRINT

    REF_PRINT("EC_KEY", r);

#endif

    if (i > 0)

        return;

#ifdef REF_CHECK

    if (i < 0) {

        fprintf(stderr, "EC_KEY_free, bad reference count\n");

        abort();

    }

#endif

    if (r->group != NULL)

        EC_GROUP_free(r->group);

    if (r->pub_key != NULL)

        EC_POINT_free(r->pub_key);

    if (r->priv_key != NULL)

        BN_clear_free(r->priv_key);

    EC_EX_DATA_free_all_data(&r->method_data);

    OPENSSL_cleanse((void *)r, sizeof(EC_KEY));

    OPENSSL_free(r);

}

EC_KEY *EC_KEY_copy(EC_KEY *dest, const EC_KEY *src)

{

    EC_EXTRA_DATA *d;

    if (dest == NULL || src == NULL) {

        ECerr(EC_F_EC_KEY_COPY, ERR_R_PASSED_NULL_PARAMETER);

        return NULL;

    }

    /* copy the parameters */

    if (src->group) {

        const EC_METHOD *meth = EC_GROUP_method_of(src->group);

        /* clear the old group */

        if (dest->group)

            EC_GROUP_free(dest->group);

        dest->group = EC_GROUP_new(meth);

        if (dest->group == NULL)

            return NULL;

        if (!EC_GROUP_copy(dest->group, src->group))

            return NULL;

    }

    /*  copy the public key */

    if (src->pub_key && src->group) {

        if (dest->pub_key)

            EC_POINT_free(dest->pub_key);

        dest->pub_key = EC_POINT_new(src->group);

        if (dest->pub_key == NULL)

            return NULL;

        if (!EC_POINT_copy(dest->pub_key, src->pub_key))

            return NULL;

    }

    /* copy the private key */

    if (src->priv_key) {

        if (dest->priv_key == NULL) {

            dest->priv_key = BN_new();

            if (dest->priv_key == NULL)

                return NULL;

        }

        if (!BN_copy(dest->priv_key, src->priv_key))

            return NULL;

    }

    /* copy method/extra data */

    EC_EX_DATA_free_all_data(&dest->method_data);

    for (d = src->method_data; d != NULL; d = d->next) {

        void *t = d->dup_func(d->data);

        if (t == NULL)

            return 0;

        if (!EC_EX_DATA_set_data

            (&dest->method_data, t, d->dup_func, d->free_func,

             d->clear_free_func))

            return 0;

    }

    /* copy the rest */

    dest->enc_flag = src->enc_flag;

    dest->conv_form = src->conv_form;

    dest->version = src->version;

    dest->flags = src->flags;

    return dest;

}

EC_KEY *EC_KEY_dup(const EC_KEY *ec_key)

{

    EC_KEY *ret = EC_KEY_new();

    if (ret == NULL)

        return NULL;

    if (EC_KEY_copy(ret, ec_key) == NULL) {

        EC_KEY_free(ret);

        return NULL;

    }

    return ret;

}

int EC_KEY_up_ref(EC_KEY *r)

{

    int i = CRYPTO_add(&r->references, 1, CRYPTO_LOCK_EC);

#ifdef REF_PRINT

    REF_PRINT("EC_KEY", r);

#endif

#ifdef REF_CHECK

    if (i < 2) {

        fprintf(stderr, "EC_KEY_up, bad reference count\n");

        abort();

    }

#endif

    return ((i > 1) ? 1 : 0);

}

int EC_KEY_generate_key(EC_KEY *eckey)

{

    int ok = 0;

    BN_CTX *ctx = NULL;

    BIGNUM *priv_key = NULL, *order = NULL;

    EC_POINT *pub_key = NULL;

#ifdef OPENSSL_FIPS

    if (FIPS_mode())

        return FIPS_ec_key_generate_key(eckey);

#endif

    if (!eckey || !eckey->group) {

        ECerr(EC_F_EC_KEY_GENERATE_KEY, ERR_R_PASSED_NULL_PARAMETER);

        return 0;

    }

    if ((order = BN_new()) == NULL)

        goto err;

    if ((ctx = BN_CTX_new()) == NULL)

        goto err;

    if (eckey->priv_key == NULL) {

        priv_key = BN_new();

        if (priv_key == NULL)

            goto err;

    } else

        priv_key = eckey->priv_key;

    if (!EC_GROUP_get_order(eckey->group, order, ctx))

        goto err;

    do

        if (!BN_rand_range(priv_key, order))

            goto err;

    while (BN_is_zero(priv_key)) ;

    if (eckey->pub_key == NULL) {

        pub_key = EC_POINT_new(eckey->group);

        if (pub_key == NULL)

            goto err;

    } else

        pub_key = eckey->pub_key;

    if (!EC_POINT_mul(eckey->group, pub_key, priv_key, NULL, NULL, ctx))

        goto err;

    eckey->priv_key = priv_key;

    eckey->pub_key = pub_key;

    ok = 1;

 err:

    if (order)

        BN_free(order);

    if (pub_key != NULL && eckey->pub_key == NULL)

        EC_POINT_free(pub_key);

    if (priv_key != NULL && eckey->priv_key == NULL)

        BN_free(priv_key);

    if (ctx != NULL)

        BN_CTX_free(ctx);

    return (ok);

}

int EC_KEY_check_key(const EC_KEY *eckey)

{

    int ok = 0;

    BN_CTX *ctx = NULL;

    const BIGNUM *order = NULL;

    EC_POINT *point = NULL;

    if (!eckey || !eckey->group || !eckey->pub_key) {

        ECerr(EC_F_EC_KEY_CHECK_KEY, ERR_R_PASSED_NULL_PARAMETER);

        return 0;

    }

    if (EC_POINT_is_at_infinity(eckey->group, eckey->pub_key)) {

        ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_POINT_AT_INFINITY);

        goto err;

    }

    if ((ctx = BN_CTX_new()) == NULL)

        goto err;

    if ((point = EC_POINT_new(eckey->group)) == NULL)

        goto err;

    /* testing whether the pub_key is on the elliptic curve */

    if (EC_POINT_is_on_curve(eckey->group, eckey->pub_key, ctx) <= 0) {

        ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_POINT_IS_NOT_ON_CURVE);

        goto err;

    }

    /* testing whether pub_key * order is the point at infinity */

    order = &eckey->group->order;

    if (BN_is_zero(order)) {

        ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_INVALID_GROUP_ORDER);

        goto err;

    }

    if (!EC_POINT_mul(eckey->group, point, NULL, eckey->pub_key, order, ctx)) {

        ECerr(EC_F_EC_KEY_CHECK_KEY, ERR_R_EC_LIB);

        goto err;

    }

    if (!EC_POINT_is_at_infinity(eckey->group, point)) {

        ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_WRONG_ORDER);

        goto err;

    }

    /*

     * in case the priv_key is present : check if generator * priv_key ==

     * pub_key

     */

    if (eckey->priv_key) {

        if (BN_cmp(eckey->priv_key, order) >= 0) {

            ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_WRONG_ORDER);

            goto err;

        }

        if (!EC_POINT_mul(eckey->group, point, eckey->priv_key,

                          NULL, NULL, ctx)) {

            ECerr(EC_F_EC_KEY_CHECK_KEY, ERR_R_EC_LIB);

            goto err;

        }

        if (EC_POINT_cmp(eckey->group, point, eckey->pub_key, ctx) != 0) {

            ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_INVALID_PRIVATE_KEY);

            goto err;

        }

    }

    ok = 1;

 err:

    if (ctx != NULL)

        BN_CTX_free(ctx);

    if (point != NULL)

        EC_POINT_free(point);

    return (ok);

}

int EC_KEY_set_public_key_affine_coordinates(EC_KEY *key, BIGNUM *x,

                                             BIGNUM *y)

{

    BN_CTX *ctx = NULL;

    BIGNUM *tx, *ty;

    EC_POINT *point = NULL;

    int ok = 0;

#ifndef OPENSSL_NO_EC2M

    int tmp_nid, is_char_two = 0;

#endif

    if (!key || !key->group || !x || !y) {

        ECerr(EC_F_EC_KEY_SET_PUBLIC_KEY_AFFINE_COORDINATES,

              ERR_R_PASSED_NULL_PARAMETER);

        return 0;

    }

    ctx = BN_CTX_new();

    if (ctx == NULL)

        return 0;

    BN_CTX_start(ctx);

    point = EC_POINT_new(key->group);

    if (!point)

        goto err;

    tx = BN_CTX_get(ctx);

    ty = BN_CTX_get(ctx);

    if (ty == NULL)

        goto err;

#ifndef OPENSSL_NO_EC2M

    tmp_nid = EC_METHOD_get_field_type(EC_GROUP_method_of(key->group));

    if (tmp_nid == NID_X9_62_characteristic_two_field)

        is_char_two = 1;

    if (is_char_two) {

        if (!EC_POINT_set_affine_coordinates_GF2m(key->group, point,

                                                  x, y, ctx))

            goto err;

        if (!EC_POINT_get_affine_coordinates_GF2m(key->group, point,

                                                  tx, ty, ctx))

            goto err;

    } else

#endif

    {

        if (!EC_POINT_set_affine_coordinates_GFp(key->group, point,

                                                 x, y, ctx))

            goto err;

        if (!EC_POINT_get_affine_coordinates_GFp(key->group, point,

                                                 tx, ty, ctx))

            goto err;

    }

    /*

     * Check if retrieved coordinates match originals: if not values are out

     * of range.

     */

    if (BN_cmp(x, tx) || BN_cmp(y, ty)) {

        ECerr(EC_F_EC_KEY_SET_PUBLIC_KEY_AFFINE_COORDINATES,

              EC_R_COORDINATES_OUT_OF_RANGE);

        goto err;

    }

    if (!EC_KEY_set_public_key(key, point))

        goto err;

    if (EC_KEY_check_key(key) == 0)

        goto err;

    ok = 1;

 err:

    BN_CTX_end(ctx);

    BN_CTX_free(ctx);

    EC_POINT_free(point);

    return ok;

}

const EC_GROUP *EC_KEY_get0_group(const EC_KEY *key)

{

    return key->group;

}

int EC_KEY_set_group(EC_KEY *key, const EC_GROUP *group)

{

    if (key->group != NULL)

        EC_GROUP_free(key->group);

    key->group = EC_GROUP_dup(group);

    return (key->group == NULL) ? 0 : 1;

}

const BIGNUM *EC_KEY_get0_private_key(const EC_KEY *key)

{

    return key->priv_key;

}

int EC_KEY_set_private_key(EC_KEY *key, const BIGNUM *priv_key)

{

    if (key->priv_key)

        BN_clear_free(key->priv_key);

    key->priv_key = BN_dup(priv_key);

    return (key->priv_key == NULL) ? 0 : 1;

}

const EC_POINT *EC_KEY_get0_public_key(const EC_KEY *key)

{

    return key->pub_key;

}

int EC_KEY_set_public_key(EC_KEY *key, const EC_POINT *pub_key)

{

    if (key->pub_key != NULL)

        EC_POINT_free(key->pub_key);

    key->pub_key = EC_POINT_dup(pub_key, key->group);

    return (key->pub_key == NULL) ? 0 : 1;

}

unsigned int EC_KEY_get_enc_flags(const EC_KEY *key)

{

    return key->enc_flag;

}

void EC_KEY_set_enc_flags(EC_KEY *key, unsigned int flags)

{

    key->enc_flag = flags;

}

point_conversion_form_t EC_KEY_get_conv_form(const EC_KEY *key)

{

    return key->conv_form;

}

void EC_KEY_set_conv_form(EC_KEY *key, point_conversion_form_t cform)

{

    key->conv_form = cform;

    if (key->group != NULL)

        EC_GROUP_set_point_conversion_form(key->group, cform);

}

void *EC_KEY_get_key_method_data(EC_KEY *key,

                                 void *(*dup_func) (void *),

                                 void (*free_func) (void *),

                                 void (*clear_free_func) (void *))

{

    void *ret;

    CRYPTO_r_lock(CRYPTO_LOCK_EC);

    ret =

        EC_EX_DATA_get_data(key->method_data, dup_func, free_func,

                            clear_free_func);

    CRYPTO_r_unlock(CRYPTO_LOCK_EC);

    return ret;

}

void *EC_KEY_insert_key_method_data(EC_KEY *key, void *data,

                                    void *(*dup_func) (void *),

                                    void (*free_func) (void *),

                                    void (*clear_free_func) (void *))

{

    EC_EXTRA_DATA *ex_data;

    CRYPTO_w_lock(CRYPTO_LOCK_EC);

    ex_data =

        EC_EX_DATA_get_data(key->method_data, dup_func, free_func,

                            clear_free_func);

    if (ex_data == NULL)

        EC_EX_DATA_set_data(&key->method_data, data, dup_func, free_func,

                            clear_free_func);

    CRYPTO_w_unlock(CRYPTO_LOCK_EC);

    return ex_data;

}

void EC_KEY_set_asn1_flag(EC_KEY *key, int flag)

{

    if (key->group != NULL)

        EC_GROUP_set_asn1_flag(key->group, flag);

}

int EC_KEY_precompute_mult(EC_KEY *key, BN_CTX *ctx)

{

    if (key->group == NULL)

        return 0;

    return EC_GROUP_precompute_mult(key->group, ctx);

}

int EC_KEY_get_flags(const EC_KEY *key)

{

    return key->flags;

}

void EC_KEY_set_flags(EC_KEY *key, int flags)

{

    key->flags |= flags;

}

void EC_KEY_clear_flags(EC_KEY *key, int flags)

{

    key->flags &= ~flags;

}