linux-imx

/*

 * Copyright (c) 2016, Intel Corporation

 * Authors: Salvatore Benedetto <salvatore.benedetto@intel.com>

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version

 * 2 of the License, or (at your option) any later version.

 */

#include <linux/kernel.h>

#include <linux/export.h>

#include <linux/err.h>

#include <linux/string.h>

#include <crypto/ecdh.h>

#include <crypto/kpp.h>

​

#define ECDH_KPP_SECRET_MIN_SIZE (sizeof(struct kpp_secret) + 2 * sizeof(short))

​

static inline u8 *ecdh_pack_data(void *dst, const void *src, size_t sz)

{

    memcpy(dst, src, sz);

    return dst + sz;

}

​

static inline const u8 *ecdh_unpack_data(void *dst, const void *src, size_t sz)

{

    memcpy(dst, src, sz);

    return src + sz;

}

​

unsigned int crypto_ecdh_key_len(const struct ecdh *params)

{

    return ECDH_KPP_SECRET_MIN_SIZE + params->key_size;

}

EXPORT_SYMBOL_GPL(crypto_ecdh_key_len);

​

int crypto_ecdh_encode_key(char *buf, unsigned int len,

               const struct ecdh *params)

{

    u8 *ptr = buf;

    struct kpp_secret secret = {

        .type = CRYPTO_KPP_SECRET_TYPE_ECDH,

        .len = len

    };

​

    if (unlikely(!buf))

        return -EINVAL;

​

    if (len != crypto_ecdh_key_len(params))

        return -EINVAL;

​

    ptr = ecdh_pack_data(ptr, &secret, sizeof(secret));

    ptr = ecdh_pack_data(ptr, &params->curve_id, sizeof(params->curve_id));

    ptr = ecdh_pack_data(ptr, &params->key_size, sizeof(params->key_size));

    ecdh_pack_data(ptr, params->key, params->key_size);

​

    return 0;

}

EXPORT_SYMBOL_GPL(crypto_ecdh_encode_key);

​

int crypto_ecdh_decode_key(const char *buf, unsigned int len,

               struct ecdh *params)

{