/* $OpenBSD: gost89imit_pmeth.c,v 1.4 2017/01/29 17:49:23 beck Exp $ */
/*
 * Copyright (c) 2014 Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
 * Copyright (c) 2005-2006 Cryptocom LTD
 *
 * 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.
 * ====================================================================
 */

#include <string.h>

#include <openssl/opensslconf.h>

#ifndef OPENSSL_NO_GOST
#include <openssl/evp.h>
#include <openssl/err.h>
#include <openssl/gost.h>
#include <openssl/x509v3.h> /* For string_to_hex */

#include "evp_locl.h"
#include "gost_locl.h"

struct gost_mac_pmeth_data {
        EVP_MD *md;
        unsigned char key[32];
        unsigned key_set :1;
};

static int
pkey_gost_mac_init(EVP_PKEY_CTX *ctx)
{
        struct gost_mac_pmeth_data *data;

        data = calloc(1, sizeof(struct gost_mac_pmeth_data));
        if (data == NULL)
                return 0;
        EVP_PKEY_CTX_set_data(ctx, data);
        return 1;
}

static void
pkey_gost_mac_cleanup(EVP_PKEY_CTX *ctx)
{
        struct gost_mac_pmeth_data *data = EVP_PKEY_CTX_get_data(ctx);
        free(data);
}

static int
pkey_gost_mac_copy(EVP_PKEY_CTX *dst, EVP_PKEY_CTX *src)
{
        struct gost_mac_pmeth_data *dst_data, *src_data;

        if (pkey_gost_mac_init(dst) == 0)
                return 0;

        src_data = EVP_PKEY_CTX_get_data(src);
        dst_data = EVP_PKEY_CTX_get_data(dst);

        *dst_data = *src_data;

        return 1;
}

static int
pkey_gost_mac_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
{
        struct gost_mac_pmeth_data *data = EVP_PKEY_CTX_get_data(ctx);
        unsigned char *keydata;

        if (!data->key_set) {
                GOSTerror(GOST_R_MAC_KEY_NOT_SET);
                return 0;
        }

        keydata = malloc(32);
        if (keydata == NULL) {
                GOSTerror(ERR_R_MALLOC_FAILURE);
                return 0;
        }
        memcpy(keydata, data->key, 32);
        EVP_PKEY_assign(pkey, NID_id_Gost28147_89_MAC, keydata);

        return 1;
}

static int
pkey_gost_mac_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2)
{
        struct gost_mac_pmeth_data *data = EVP_PKEY_CTX_get_data(ctx);

        switch (type) {
        case EVP_PKEY_CTRL_MD:
                if (EVP_MD_type(p2) != NID_id_Gost28147_89_MAC) {
                        GOSTerror(GOST_R_INVALID_DIGEST_TYPE);
                        return 0;
                }
                data->md = p2;
                return 1;

        case EVP_PKEY_CTRL_SET_MAC_KEY:
                if (p1 != 32) {
                        GOSTerror(GOST_R_INVALID_MAC_KEY_LENGTH);
                        return 0;
                }

                memcpy(data->key, p2, 32);
                data->key_set = 1;
                return 1;

        case EVP_PKEY_CTRL_DIGESTINIT:
            {
                EVP_MD_CTX *mctx = p2;
                void *key;

                if (!data->key_set) {
                        EVP_PKEY *pkey = EVP_PKEY_CTX_get0_pkey(ctx);
                        if (pkey == NULL) {
                                GOSTerror(GOST_R_MAC_KEY_NOT_SET);
                                return 0;
                        }
                        key = EVP_PKEY_get0(pkey);
                        if (key == NULL) {
                                GOSTerror(GOST_R_MAC_KEY_NOT_SET);
                                return 0;
                        }
                } else {
                        key = &(data->key);
                }
                if (mctx->digest->md_ctrl == NULL)
                        return 0;
                return mctx->digest->md_ctrl(mctx, EVP_MD_CTRL_SET_KEY, 32 * 8,
                    key);
            }

        }

        return -2;
}

static int
pkey_gost_mac_ctrl_str(EVP_PKEY_CTX *ctx, const char *type, const char *value)
{
        if (value == NULL)
                return 0;
        if (strcmp(type, "key") == 0) {
                void *p = (void *)value;
                return pkey_gost_mac_ctrl(ctx, EVP_PKEY_CTRL_SET_MAC_KEY,
                    strlen(value), p);
        }
        if (strcmp(type, "hexkey") == 0) {
                unsigned char *key;
                int r;
                long keylen;

                key = string_to_hex(value, &keylen);
                if (key == NULL)
                        return 0;
                r = pkey_gost_mac_ctrl(ctx, EVP_PKEY_CTRL_SET_MAC_KEY, keylen,
                    key);
                free(key);
                return r;
        }
        return -2;
}

static int
pkey_gost_mac_signctx_init(EVP_PKEY_CTX *ctx, EVP_MD_CTX *mctx)
{
        return 1;
}

static int
pkey_gost_mac_signctx(EVP_PKEY_CTX *ctx, unsigned char *sig, size_t *siglen,
    EVP_MD_CTX *mctx)
{
        /* for platforms where sizeof(int) != sizeof(size_t)*/
        unsigned int tmpsiglen = *siglen;
        int ret;

        if (sig == NULL) {
                *siglen = 4;
                return 1;
        }

        ret = EVP_DigestFinal_ex(mctx, sig, &tmpsiglen);
        *siglen = tmpsiglen;
        return ret;
}

const EVP_PKEY_METHOD gostimit_pkey_meth = {
        .pkey_id = EVP_PKEY_GOSTIMIT,

        .init = pkey_gost_mac_init,
        .cleanup = pkey_gost_mac_cleanup,
        .copy = pkey_gost_mac_copy,

        .keygen = pkey_gost_mac_keygen,

        .signctx_init = pkey_gost_mac_signctx_init,
        .signctx = pkey_gost_mac_signctx,

        .ctrl = pkey_gost_mac_ctrl,
        .ctrl_str = pkey_gost_mac_ctrl_str,
};

#endif