/src/wolfssl/wolfcrypt/src/curve448.c

Source (jump to first uncovered line)
/* curve448.c
 *
 * Copyright (C) 2006-2022 wolfSSL Inc.
 *
 * This file is part of wolfSSL.
 *
 * wolfSSL 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.
 *
 * wolfSSL is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
 */

/* Implemented to: RFC 7748 */

/* Based On Daniel J Bernstein's curve25519 Public Domain ref10 work.
 * Reworked for curve448 by Sean Parkinson.
 */

#ifdef HAVE_CONFIG_H
    #include <config.h>
#endif

#include <wolfssl/wolfcrypt/settings.h>

#ifdef HAVE_CURVE448

#include <wolfssl/wolfcrypt/curve448.h>
#include <wolfssl/wolfcrypt/error-crypt.h>
#ifdef NO_INLINE
    #include <wolfssl/wolfcrypt/misc.h>
#else
    #define WOLFSSL_MISC_INCLUDED
    #include <wolfcrypt/src/misc.c>
#endif

int wc_curve448_make_pub(int public_size, byte* pub, int private_size,
    const byte* priv)
{
    int ret;
    unsigned char basepoint[CURVE448_KEY_SIZE] = {5};

    if ((pub == NULL) || (priv == NULL)) {
        return ECC_BAD_ARG_E;
    }
    if ((public_size  != CURVE448_PUB_KEY_SIZE) ||
        (private_size != CURVE448_KEY_SIZE)) {
        return ECC_BAD_ARG_E;
    }

    fe448_init();

    /* compute public key */
    ret = curve448(pub, priv, basepoint);

    return ret;
}


/* Make a new curve448 private/public key.
 *
 * rng      [in]  Random number generator.
 * keysize  [in]  Size of the key to generate.
 * key      [in]  Curve448 key object.
 * returns BAD_FUNC_ARG when rng or key are NULL,
 *         ECC_BAD_ARG_E when keysize is not CURVE448_KEY_SIZE,
 *         0 otherwise.
 */
int wc_curve448_make_key(WC_RNG* rng, int keysize, curve448_key* key)
{
    int  ret = 0;

    if ((key == NULL) || (rng == NULL)) {
        ret = BAD_FUNC_ARG;
    }

    /* currently only a key size of 56 bytes is used */
    if ((ret == 0) && (keysize != CURVE448_KEY_SIZE)) {
        ret = ECC_BAD_ARG_E;
    }

    if (ret == 0) {
        /* random number for private key */
        ret = wc_RNG_GenerateBlock(rng, key->k, keysize);
    }
    if (ret == 0) {
        key->privSet = 1;

        /* clamp private */
        key->k[0] &= 0xfc;
        key->k[CURVE448_KEY_SIZE-1] |= 0x80;

        /* compute public */
        ret = wc_curve448_make_pub((int)sizeof(key->p), key->p,
                                   (int)sizeof(key->k), key->k);
        if (ret == 0) {
            key->pubSet = 1;
        }
        else {
            ForceZero(key->k, sizeof(key->k));
            XMEMSET(key->p, 0, sizeof(key->p));
        }
    }

    return ret;
}

#ifdef HAVE_CURVE448_SHARED_SECRET

/* Calculate the shared secret from the private key and peer's public key.
 * Calculation over curve448.
 * Secret encoded big-endian.
 *
 * private_key  [in]      Curve448 private key.
 * public_key   [in]      Curve448 public key.
 * out          [in]      Array to hold shared secret.
 * outLen       [in/out]  On in, the number of bytes in array.
 *                        On out, the number bytes put into array.
 * returns BAD_FUNC_ARG when a parameter is NULL or outLen is less than
 *         CURVE448_KEY_SIZE,
 *         0 otherwise.
 */
int wc_curve448_shared_secret(curve448_key* private_key,
                              curve448_key* public_key,
                              byte* out, word32* outLen)
{
    return wc_curve448_shared_secret_ex(private_key, public_key, out, outLen,
                                        EC448_BIG_ENDIAN);
}

/* Calculate the shared secret from the private key and peer's public key.
 * Calculation over curve448.
 *
 * private_key  [in]      Curve448 private key.
 * public_key   [in]      Curve448 public key.
 * out          [in]      Array to hold shared secret.
 * outLen       [in/out]  On in, the number of bytes in array.
 *                        On out, the number bytes put into array.
 * endian       [in]      Endianness to use when encoding number in array.
 * returns BAD_FUNC_ARG when a parameter is NULL or outLen is less than
 *         CURVE448_PUB_KEY_SIZE,
 *         0 otherwise.
 */
int wc_curve448_shared_secret_ex(curve448_key* private_key,
                                 curve448_key* public_key,
                                 byte* out, word32* outLen, int endian)
{
    unsigned char o[CURVE448_PUB_KEY_SIZE];
    int ret = 0;
    int i;

    /* sanity check */
    if ((private_key == NULL) || (public_key == NULL) || (out == NULL) ||
                        (outLen == NULL) || (*outLen < CURVE448_PUB_KEY_SIZE)) {
        ret = BAD_FUNC_ARG;
    }
    /* make sure we have a populated private and public key */
    if (ret == 0 && (!private_key->privSet || !public_key->pubSet)) {
        ret = ECC_BAD_ARG_E;
    }

    if (ret == 0) {
        ret = curve448(o, private_key->k, public_key->p);
    }
#ifdef WOLFSSL_ECDHX_SHARED_NOT_ZERO
    if (ret == 0) {
        byte t = 0;
        for (i = 0; i < CURVE448_PUB_KEY_SIZE; i++) {
            t |= o[i];
        }
        if (t == 0) {
            ret = ECC_OUT_OF_RANGE_E;
        }
    }
#endif
    if (ret == 0) {
        if (endian == EC448_BIG_ENDIAN) {
            /* put shared secret key in Big Endian format */
            for (i = 0; i < CURVE448_PUB_KEY_SIZE; i++) {
                 out[i] = o[CURVE448_PUB_KEY_SIZE - i -1];
            }
        }
        else {
            /* put shared secret key in Little Endian format */
            XMEMCPY(out, o, CURVE448_PUB_KEY_SIZE);
        }

        *outLen = CURVE448_PUB_KEY_SIZE;
    }

    ForceZero(o, CURVE448_PUB_KEY_SIZE);

    return ret;
}

#endif /* HAVE_CURVE448_SHARED_SECRET */

#ifdef HAVE_CURVE448_KEY_EXPORT

/* Export the curve448 public key.
 * Public key encoded big-endian.
 *
 * key     [in]      Curve448 public key.
 * out     [in]      Array to hold public key.
 * outLen  [in/out]  On in, the number of bytes in array.
 *                   On out, the number bytes put into array.
 * returns BAD_FUNC_ARG when a parameter is NULL,
 *         ECC_BAD_ARG_E when outLen is less than CURVE448_PUB_KEY_SIZE,
 *         0 otherwise.
 */
int wc_curve448_export_public(curve448_key* key, byte* out, word32* outLen)
{
    return wc_curve448_export_public_ex(key, out, outLen, EC448_BIG_ENDIAN);
}

/* Export the curve448 public key.
 *
 * key     [in]      Curve448 public key.
 * out     [in]      Array to hold public key.
 * outLen  [in/out]  On in, the number of bytes in array.
 *                   On out, the number bytes put into array.
 * endian  [in]      Endianness to use when encoding number in array.
 * returns BAD_FUNC_ARG when a parameter is NULL,
 *         ECC_BAD_ARG_E when outLen is less than CURVE448_PUB_KEY_SIZE,
 *         0 otherwise.
 */
int wc_curve448_export_public_ex(curve448_key* key, byte* out, word32* outLen,
                                 int endian)
{
    int ret = 0;
    int i;

    if ((key == NULL) || (out == NULL) || (outLen == NULL)) {
        ret = BAD_FUNC_ARG;
    }

    /* check and set outgoing key size */
    if ((ret == 0) && (*outLen < CURVE448_PUB_KEY_SIZE)) {
        *outLen = CURVE448_PUB_KEY_SIZE;
        ret = ECC_BAD_ARG_E;
    }
    if (ret == 0) {
        /* calculate public if missing */
        if (!key->pubSet) {
            ret = wc_curve448_make_pub((int)sizeof(key->p), key->p,
                                       (int)sizeof(key->k), key->k);
            key->pubSet = (ret == 0);
        }
    }
    if (ret == 0) {
        *outLen = CURVE448_PUB_KEY_SIZE;
        if (endian == EC448_BIG_ENDIAN) {
            /* read keys in Big Endian format */
            for (i = 0; i < CURVE448_PUB_KEY_SIZE; i++) {
                out[i] = key->p[CURVE448_PUB_KEY_SIZE - i - 1];
            }
        }
        else {
            XMEMCPY(out, key->p, CURVE448_PUB_KEY_SIZE);
        }
    }

    return ret;
}

#endif /* HAVE_CURVE448_KEY_EXPORT */

#ifdef HAVE_CURVE448_KEY_IMPORT

/* Import a curve448 public key from a byte array.
 * Public key encoded in big-endian.
 *
 * in      [in]  Array holding public key.
 * inLen   [in]  Number of bytes of data in array.
 * key     [in]  Curve448 public key.
 * returns BAD_FUNC_ARG when a parameter is NULL,
 *         ECC_BAD_ARG_E when inLen is less than CURVE448_PUB_KEY_SIZE,
 *         0 otherwise.
 */
int wc_curve448_import_public(const byte* in, word32 inLen, curve448_key* key)
{
    return wc_curve448_import_public_ex(in, inLen, key, EC448_BIG_ENDIAN);
}

/* Import a curve448 public key from a byte array.
 *
 * in      [in]  Array holding public key.
 * inLen   [in]  Number of bytes of data in array.
 * key     [in]  Curve448 public key.
 * endian  [in]  Endianness of encoded number in byte array.
 * returns BAD_FUNC_ARG when a parameter is NULL,
 *         ECC_BAD_ARG_E when inLen is less than CURVE448_PUB_KEY_SIZE,
 *         0 otherwise.
 */
int wc_curve448_import_public_ex(const byte* in, word32 inLen,
                                 curve448_key* key, int endian)
{
    int ret = 0;
    int i;

    /* sanity check */
    if ((key == NULL) || (in == NULL)) {
        ret = BAD_FUNC_ARG;
    }

    /* check size of incoming keys */
    if ((ret == 0) && (inLen != CURVE448_PUB_KEY_SIZE)) {
       ret = ECC_BAD_ARG_E;
    }

    if (ret == 0) {
        if (endian == EC448_BIG_ENDIAN) {
            /* read keys in Big Endian format */
            for (i = 0; i < CURVE448_PUB_KEY_SIZE; i++) {
                key->p[i] = in[CURVE448_PUB_KEY_SIZE - i - 1];
            }
        }
        else
            XMEMCPY(key->p, in, inLen);
        key->pubSet = 1;
    }

    return ret;
}

/* Check the public key value (big or little endian)
 *
 * pub     [in]  Public key bytes.
 * pubSz   [in]  Size of public key in bytes.
 * endian  [in]  Public key bytes passed in as big-endian or little-endian.
 * returns BAD_FUNC_ARGS when pub is NULL,
 *         ECC_BAD_ARG_E when key length is not 56 bytes, public key value is
 *         zero or one;
 *         BUFFER_E when size of public key is zero;
 *         0 otherwise.
 */
int wc_curve448_check_public(const byte* pub, word32 pubSz, int endian)
{
    int ret = 0;
    word32 i;

    if (pub == NULL) {
        ret = BAD_FUNC_ARG;
    }

    /* Check for empty key data */
    if ((ret == 0) && (pubSz == 0)) {
        ret = BUFFER_E;
    }

    /* Check key length */
    if ((ret == 0) && (pubSz != CURVE448_PUB_KEY_SIZE)) {
        ret = ECC_BAD_ARG_E;
    }

    if (ret == 0) {
        if (endian == EC448_LITTLE_ENDIAN) {
            /* Check for value of zero or one */
            for (i = CURVE448_PUB_KEY_SIZE - 1; i > 0; i--) {
                if (pub[i] != 0) {
                    break;
                }
            }
            if ((i == 0) && (pub[0] == 0 || pub[0] == 1)) {
                return ECC_BAD_ARG_E;
            }
            /* Check for order-1 or higher */
            for (i = CURVE448_PUB_KEY_SIZE - 1; i > 28; i--) {
                if (pub[i] != 0xff) {
                    break;
                }
            }
            if ((i == 28) && (pub[i] == 0xff)) {
                return ECC_BAD_ARG_E;
            }
            if ((i == 28) && (pub[i] == 0xfe)) {
                for (--i; i > 0; i--) {
                    if (pub[i] != 0xff) {
                        break;
                    }
                }
                if ((i == 0) && (pub[i] >= 0xfe)) {
                    return ECC_BAD_ARG_E;
                }
            }
        }
        else {
            /* Check for value of zero or one */
            for (i = 0; i < CURVE448_PUB_KEY_SIZE-1; i++) {
                if (pub[i] != 0) {
                    break;
                }
            }
            if ((i == CURVE448_PUB_KEY_SIZE - 1) &&
                (pub[i] == 0 || pub[i] == 1)) {
                ret = ECC_BAD_ARG_E;
            }
            /* Check for order-1 or higher */
            for (i = 0; i < 27; i++) {
                if (pub[i] != 0xff) {
                    break;
                }
            }
            if ((i == 27) && (pub[i] == 0xff)) {
                return ECC_BAD_ARG_E;
            }
            if ((i == 27) && (pub[i] == 0xfe)) {
                for (++i; i < CURVE448_PUB_KEY_SIZE - 1; i--) {
                    if (pub[i] != 0xff) {
                        break;
                    }
                }
                if ((i == CURVE448_PUB_KEY_SIZE) && (pub[i] >= 0xfe)) {
                    return ECC_BAD_ARG_E;
                }
            }
        }
    }

    return ret;
}

#endif /* HAVE_CURVE448_KEY_IMPORT */


#ifdef HAVE_CURVE448_KEY_EXPORT

/* Export the curve448 private key raw form.
 * Private key encoded big-endian.
 *
 * key     [in]      Curve448 private key.
 * out     [in]      Array to hold private key.
 * outLen  [in/out]  On in, the number of bytes in array.
 *                   On out, the number bytes put into array.
 * returns BAD_FUNC_ARG when a parameter is NULL,
 *         ECC_BAD_ARG_E when outLen is less than CURVE448_KEY_SIZE,
 *         0 otherwise.
 */
int wc_curve448_export_private_raw(curve448_key* key, byte* out, word32* outLen)
{
    return wc_curve448_export_private_raw_ex(key, out, outLen,
                                             EC448_BIG_ENDIAN);
}

/* Export the curve448 private key raw form.
 *
 * key     [in]      Curve448 private key.
 * out     [in]      Array to hold private key.
 * outLen  [in/out]  On in, the number of bytes in array.
 *                   On out, the number bytes put into array.
 * endian  [in]      Endianness to use when encoding number in array.
 * returns BAD_FUNC_ARG when a parameter is NULL,
 *         ECC_BAD_ARG_E when outLen is less than CURVE448_KEY_SIZE,
 *         0 otherwise.
 */
int wc_curve448_export_private_raw_ex(curve448_key* key, byte* out,
                                      word32* outLen, int endian)
{
    int ret = 0;
    int i;

    /* sanity check */
    if ((key == NULL) || (out == NULL) || (outLen == NULL)) {
        ret = BAD_FUNC_ARG;
    }

    /* check size of outgoing buffer */
    if ((ret == 0) && (*outLen < CURVE448_KEY_SIZE)) {
        *outLen = CURVE448_KEY_SIZE;
        ret = ECC_BAD_ARG_E;
    }
    if (ret == 0) {
        *outLen = CURVE448_KEY_SIZE;

        if (endian == EC448_BIG_ENDIAN) {
            /* put the key in Big Endian format */
            for (i = 0; i < CURVE448_KEY_SIZE; i++) {
                out[i] = key->k[CURVE448_KEY_SIZE - i - 1];
            }
        }
        else {
            XMEMCPY(out, key->k, CURVE448_KEY_SIZE);
        }
    }

    return ret;
}

/* Export the curve448 private and public keys in raw form.
 * Private and public key encoded big-endian.
 *
 * key     [in]      Curve448 private key.
 * priv    [in]      Array to hold private key.
 * privSz  [in/out]  On in, the number of bytes in private key array.
 *                   On out, the number bytes put into private key array.
 * pub     [in]      Array to hold public key.
 * pubSz   [in/out]  On in, the number of bytes in public key array.
 *                   On out, the number bytes put into public key array.
 * returns BAD_FUNC_ARG when a parameter is NULL,
 *         ECC_BAD_ARG_E when privSz is less than CURVE448_KEY_SIZE or pubSz is
 *         less than CURVE448_PUB_KEY_SIZE,
 *         0 otherwise.
 */
int wc_curve448_export_key_raw(curve448_key* key, byte* priv, word32 *privSz,
                               byte* pub, word32 *pubSz)
{
    return wc_curve448_export_key_raw_ex(key, priv, privSz, pub, pubSz,
                                         EC448_BIG_ENDIAN);
}

/* Export the curve448 private and public keys in raw form.
 *
 * key     [in]      Curve448 private key.
 * priv    [in]      Array to hold private key.
 * privSz  [in/out]  On in, the number of bytes in private key array.
 *                   On out, the number bytes put into private key array.
 * pub     [in]      Array to hold public key.
 * pubSz   [in/out]  On in, the number of bytes in public key array.
 *                   On out, the number bytes put into public key array.
 * endian  [in]      Endianness to use when encoding number in array.
 * returns BAD_FUNC_ARG when a parameter is NULL,
 *         ECC_BAD_ARG_E when privSz is less than CURVE448_KEY_SIZE or pubSz is
 *         less than CURVE448_PUB_KEY_SIZE,
 *         0 otherwise.
 */
int wc_curve448_export_key_raw_ex(curve448_key* key, byte* priv, word32 *privSz,
                                  byte* pub, word32 *pubSz, int endian)
{
    int ret;

    /* export private part */
    ret = wc_curve448_export_private_raw_ex(key, priv, privSz, endian);
    if (ret == 0) {
        /* export public part */
        ret = wc_curve448_export_public_ex(key, pub, pubSz, endian);
    }

    return ret;
}

#endif /* HAVE_CURVE448_KEY_EXPORT */

#ifdef HAVE_CURVE448_KEY_IMPORT

/* Import curve448 private and public keys from a byte arrays.
 * Private and public keys encoded in big-endian.
 *
 * piv     [in]  Array holding private key.
 * privSz  [in]  Number of bytes of data in private key array.
 * pub     [in]  Array holding public key.
 * pubSz   [in]  Number of bytes of data in public key array.
 * key     [in]  Curve448 private/public key.
 * returns BAD_FUNC_ARG when a parameter is NULL,
 *         ECC_BAD_ARG_E when privSz is less than CURVE448_KEY_SIZE or pubSz is
 *         less than CURVE448_PUB_KEY_SIZE,
 *         0 otherwise.
 */
int wc_curve448_import_private_raw(const byte* priv, word32 privSz,
                                   const byte* pub, word32 pubSz,
                                   curve448_key* key)
{
    return wc_curve448_import_private_raw_ex(priv, privSz, pub, pubSz, key,
                                             EC448_BIG_ENDIAN);
}

/* Import curve448 private and public keys from a byte arrays.
 *
 * piv     [in]  Array holding private key.
 * privSz  [in]  Number of bytes of data in private key array.
 * pub     [in]  Array holding public key.
 * pubSz   [in]  Number of bytes of data in public key array.
 * key     [in]  Curve448 private/public key.
 * endian  [in]  Endianness of encoded numbers in byte arrays.
 * returns BAD_FUNC_ARG when a parameter is NULL,
 *         ECC_BAD_ARG_E when privSz is less than CURVE448_KEY_SIZE or pubSz is
 *         less than CURVE448_PUB_KEY_SIZE,
 *         0 otherwise.
 */
int wc_curve448_import_private_raw_ex(const byte* priv, word32 privSz,
                                      const byte* pub, word32 pubSz,
                                      curve448_key* key, int endian)
{
    int ret;

    /* import private part */
    ret = wc_curve448_import_private_ex(priv, privSz, key, endian);
    if (ret == 0) {
        /* import public part */
        return wc_curve448_import_public_ex(pub, pubSz, key, endian);
    }

    return ret;
}

/* Import curve448 private key from a byte array.
 * Private key encoded in big-endian.
 *
 * piv     [in]  Array holding private key.
 * privSz  [in]  Number of bytes of data in private key array.
 * key     [in]  Curve448 private/public key.
 * returns BAD_FUNC_ARG when a parameter is NULL,
 *         ECC_BAD_ARG_E when privSz is less than CURVE448_KEY_SIZE,
 *         0 otherwise.
 */
int wc_curve448_import_private(const byte* priv, word32 privSz,
                               curve448_key* key)
{
    return wc_curve448_import_private_ex(priv, privSz, key, EC448_BIG_ENDIAN);
}

/* Import curve448 private key from a byte array.
 *
 * piv     [in]  Array holding private key.
 * privSz  [in]  Number of bytes of data in private key array.
 * key     [in]  Curve448 private/public key.
 * endian  [in]  Endianness of encoded number in byte array.
 * returns BAD_FUNC_ARG when a parameter is NULL,
 *         ECC_BAD_ARG_E when privSz is less than CURVE448_KEY_SIZE,
 *         0 otherwise.
 */
int wc_curve448_import_private_ex(const byte* priv, word32 privSz,
                                  curve448_key* key, int endian)
{
    int ret = 0;
    int i;

    /* sanity check */
    if ((key == NULL) || (priv == NULL)) {
        ret = BAD_FUNC_ARG;
    }

    /* check size of incoming keys */
    if ((ret == 0) && ((int)privSz != CURVE448_KEY_SIZE)) {
        ret = ECC_BAD_ARG_E;
    }

    if (ret == 0) {
        if (endian == EC448_BIG_ENDIAN) {
            /* read the key in Big Endian format */
            for (i = 0; i < CURVE448_KEY_SIZE; i++) {
                key->k[i] = priv[CURVE448_KEY_SIZE - i - 1];
            }
        }
        else {
            XMEMCPY(key->k, priv, CURVE448_KEY_SIZE);
        }

        /* Clamp the key */
        key->k[0] &= 0xfc;
        key->k[CURVE448_KEY_SIZE-1] |= 0x80;

        key->privSet = 1;
    }

    return ret;
}

#endif /* HAVE_CURVE448_KEY_IMPORT */


/* Initialize the curve448 key.
 *
 * key  [in]  Curve448 key object.
 * returns BAD_FUNC_ARG when key is NULL,
 *         0 otherwise.
 */
int wc_curve448_init(curve448_key* key)
{
    int ret = 0;

    if (key == NULL) {
       ret = BAD_FUNC_ARG;
    }

    if (ret == 0) {
        XMEMSET(key, 0, sizeof(*key));

        fe448_init();

    #ifdef WOLFSSL_CHECK_MEM_ZERO
        wc_MemZero_Add("wc_curve448_init key->k", &key->k, CURVE448_KEY_SIZE);
    #endif
    }

    return ret;
}


/* Clears the curve448 key data.
 *
 * key  [in]  Curve448 key object.
 */
void wc_curve448_free(curve448_key* key)
{
    if (key != NULL) {
        ForceZero(key->k, sizeof(key->k));
        XMEMSET(key->p, 0, sizeof(key->p));
        key->pubSet = 0;
        key->privSet = 0;
    #ifdef WOLFSSL_CHECK_MEM_ZERO
        wc_MemZero_Check(key, sizeof(curve448_key));
    #endif
    }
}


/* Get the curve448 key's size.
 *
 * key  [in]  Curve448 key object.
 * returns 0 if key is NULL,
 *         CURVE448_KEY_SIZE otherwise.
 */
int wc_curve448_size(curve448_key* key)
{
    int ret = 0;

    if (key != NULL) {
        ret = CURVE448_KEY_SIZE;
    }

    return ret;
}

#endif /* HAVE_CURVE448 */


Coverage Report

Created: 2023-02-22 06:39

Line	Count	Source (jump to first uncovered line)
1		/* curve448.c
2		*
3		* Copyright (C) 2006-2022 wolfSSL Inc.
4		*
5		* This file is part of wolfSSL.
6		*
7		* wolfSSL is free software; you can redistribute it and/or modify
8		* it under the terms of the GNU General Public License as published by
9		* the Free Software Foundation; either version 2 of the License, or
10		* (at your option) any later version.
11		*
12		* wolfSSL is distributed in the hope that it will be useful,
13		* but WITHOUT ANY WARRANTY; without even the implied warranty of
14		* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15		* GNU General Public License for more details.
16		*
17		* You should have received a copy of the GNU General Public License
18		* along with this program; if not, write to the Free Software
19		* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
20		*/
21
22		/* Implemented to: RFC 7748 */
23
24		/* Based On Daniel J Bernstein's curve25519 Public Domain ref10 work.
25		* Reworked for curve448 by Sean Parkinson.
26		*/
27
28		#ifdef HAVE_CONFIG_H
29		#include <config.h>
30		#endif
31
32		#include <wolfssl/wolfcrypt/settings.h>
33
34		#ifdef HAVE_CURVE448
35
36		#include <wolfssl/wolfcrypt/curve448.h>
37		#include <wolfssl/wolfcrypt/error-crypt.h>
38		#ifdef NO_INLINE
39		#include <wolfssl/wolfcrypt/misc.h>
40		#else
41		#define WOLFSSL_MISC_INCLUDED
42		#include <wolfcrypt/src/misc.c>
43		#endif
44
45		int wc_curve448_make_pub(int public_size, byte* pub, int private_size,
46		const byte* priv)
47	0	{
48	0	int ret;
49	0	unsigned char basepoint[CURVE448_KEY_SIZE] = {5};
50
51	0	if ((pub == NULL) \|\| (priv == NULL)) {
52	0	return ECC_BAD_ARG_E;
53	0	}
54	0	if ((public_size != CURVE448_PUB_KEY_SIZE) \|\|
55	0	(private_size != CURVE448_KEY_SIZE)) {
56	0	return ECC_BAD_ARG_E;
57	0	}
58
59	0	fe448_init();
60
61		/* compute public key */
62	0	ret = curve448(pub, priv, basepoint);
63
64	0	return ret;
65	0	}
66
67
68		/* Make a new curve448 private/public key.
69		*
70		* rng [in] Random number generator.
71		* keysize [in] Size of the key to generate.
72		* key [in] Curve448 key object.
73		* returns BAD_FUNC_ARG when rng or key are NULL,
74		* ECC_BAD_ARG_E when keysize is not CURVE448_KEY_SIZE,
75		* 0 otherwise.
76		*/
77		int wc_curve448_make_key(WC_RNG* rng, int keysize, curve448_key* key)
78	0	{
79	0	int ret = 0;
80
81	0	if ((key == NULL) \|\| (rng == NULL)) {
82	0	ret = BAD_FUNC_ARG;
83	0	}
84
85		/* currently only a key size of 56 bytes is used */
86	0	if ((ret == 0) && (keysize != CURVE448_KEY_SIZE)) {
87	0	ret = ECC_BAD_ARG_E;
88	0	}
89
90	0	if (ret == 0) {
91		/* random number for private key */
92	0	ret = wc_RNG_GenerateBlock(rng, key->k, keysize);
93	0	}
94	0	if (ret == 0) {
95	0	key->privSet = 1;
96
97		/* clamp private */
98	0	key->k[0] &= 0xfc;
99	0	key->k[CURVE448_KEY_SIZE-1] \|= 0x80;
100
101		/* compute public */
102	0	ret = wc_curve448_make_pub((int)sizeof(key->p), key->p,
103	0	(int)sizeof(key->k), key->k);
104	0	if (ret == 0) {
105	0	key->pubSet = 1;
106	0	}
107	0	else {
108	0	ForceZero(key->k, sizeof(key->k));
109	0	XMEMSET(key->p, 0, sizeof(key->p));
110	0	}
111	0	}
112
113	0	return ret;
114	0	}
115
116		#ifdef HAVE_CURVE448_SHARED_SECRET
117
118		/* Calculate the shared secret from the private key and peer's public key.
119		* Calculation over curve448.
120		* Secret encoded big-endian.
121		*
122		* private_key [in] Curve448 private key.
123		* public_key [in] Curve448 public key.
124		* out [in] Array to hold shared secret.
125		* outLen [in/out] On in, the number of bytes in array.
126		* On out, the number bytes put into array.
127		* returns BAD_FUNC_ARG when a parameter is NULL or outLen is less than
128		* CURVE448_KEY_SIZE,
129		* 0 otherwise.
130		*/
131		int wc_curve448_shared_secret(curve448_key* private_key,
132		curve448_key* public_key,
133		byte* out, word32* outLen)
134	0	{
135	0	return wc_curve448_shared_secret_ex(private_key, public_key, out, outLen,
136	0	EC448_BIG_ENDIAN);
137	0	}
138
139		/* Calculate the shared secret from the private key and peer's public key.
140		* Calculation over curve448.
141		*
142		* private_key [in] Curve448 private key.
143		* public_key [in] Curve448 public key.
144		* out [in] Array to hold shared secret.
145		* outLen [in/out] On in, the number of bytes in array.
146		* On out, the number bytes put into array.
147		* endian [in] Endianness to use when encoding number in array.
148		* returns BAD_FUNC_ARG when a parameter is NULL or outLen is less than
149		* CURVE448_PUB_KEY_SIZE,
150		* 0 otherwise.
151		*/
152		int wc_curve448_shared_secret_ex(curve448_key* private_key,
153		curve448_key* public_key,
154		byte* out, word32* outLen, int endian)
155	0	{
156	0	unsigned char o[CURVE448_PUB_KEY_SIZE];
157	0	int ret = 0;
158	0	int i;
159
160		/* sanity check */
161	0	if ((private_key == NULL) \|\| (public_key == NULL) \|\| (out == NULL) \|\|
162	0	(outLen == NULL) \|\| (*outLen < CURVE448_PUB_KEY_SIZE)) {
163	0	ret = BAD_FUNC_ARG;
164	0	}
165		/* make sure we have a populated private and public key */
166	0	if (ret == 0 && (!private_key->privSet \|\| !public_key->pubSet)) {
167	0	ret = ECC_BAD_ARG_E;
168	0	}
169
170	0	if (ret == 0) {
171	0	ret = curve448(o, private_key->k, public_key->p);
172	0	}
173		#ifdef WOLFSSL_ECDHX_SHARED_NOT_ZERO
174		if (ret == 0) {
175		byte t = 0;
176		for (i = 0; i < CURVE448_PUB_KEY_SIZE; i++) {
177		t \|= o[i];
178		}
179		if (t == 0) {
180		ret = ECC_OUT_OF_RANGE_E;
181		}
182		}
183		#endif
184	0	if (ret == 0) {
185	0	if (endian == EC448_BIG_ENDIAN) {
186		/* put shared secret key in Big Endian format */
187	0	for (i = 0; i < CURVE448_PUB_KEY_SIZE; i++) {
188	0	out[i] = o[CURVE448_PUB_KEY_SIZE - i -1];
189	0	}
190	0	}
191	0	else {
192		/* put shared secret key in Little Endian format */
193	0	XMEMCPY(out, o, CURVE448_PUB_KEY_SIZE);
194	0	}
195
196	0	*outLen = CURVE448_PUB_KEY_SIZE;
197	0	}
198
199	0	ForceZero(o, CURVE448_PUB_KEY_SIZE);
200
201	0	return ret;
202	0	}
203
204		#endif /* HAVE_CURVE448_SHARED_SECRET */
205
206		#ifdef HAVE_CURVE448_KEY_EXPORT
207
208		/* Export the curve448 public key.
209		* Public key encoded big-endian.
210		*
211		* key [in] Curve448 public key.
212		* out [in] Array to hold public key.
213		* outLen [in/out] On in, the number of bytes in array.
214		* On out, the number bytes put into array.
215		* returns BAD_FUNC_ARG when a parameter is NULL,
216		* ECC_BAD_ARG_E when outLen is less than CURVE448_PUB_KEY_SIZE,
217		* 0 otherwise.
218		*/
219		int wc_curve448_export_public(curve448_key* key, byte* out, word32* outLen)
220	0	{
221	0	return wc_curve448_export_public_ex(key, out, outLen, EC448_BIG_ENDIAN);
222	0	}
223
224		/* Export the curve448 public key.
225		*
226		* key [in] Curve448 public key.
227		* out [in] Array to hold public key.
228		* outLen [in/out] On in, the number of bytes in array.
229		* On out, the number bytes put into array.
230		* endian [in] Endianness to use when encoding number in array.
231		* returns BAD_FUNC_ARG when a parameter is NULL,
232		* ECC_BAD_ARG_E when outLen is less than CURVE448_PUB_KEY_SIZE,
233		* 0 otherwise.
234		*/
235		int wc_curve448_export_public_ex(curve448_key* key, byte* out, word32* outLen,
236		int endian)
237	0	{
238	0	int ret = 0;
239	0	int i;
240
241	0	if ((key == NULL) \|\| (out == NULL) \|\| (outLen == NULL)) {
242	0	ret = BAD_FUNC_ARG;
243	0	}
244
245		/* check and set outgoing key size */
246	0	if ((ret == 0) && (*outLen < CURVE448_PUB_KEY_SIZE)) {
247	0	*outLen = CURVE448_PUB_KEY_SIZE;
248	0	ret = ECC_BAD_ARG_E;
249	0	}
250	0	if (ret == 0) {
251		/* calculate public if missing */
252	0	if (!key->pubSet) {
253	0	ret = wc_curve448_make_pub((int)sizeof(key->p), key->p,
254	0	(int)sizeof(key->k), key->k);
255	0	key->pubSet = (ret == 0);
256	0	}
257	0	}
258	0	if (ret == 0) {
259	0	*outLen = CURVE448_PUB_KEY_SIZE;
260	0	if (endian == EC448_BIG_ENDIAN) {
261		/* read keys in Big Endian format */
262	0	for (i = 0; i < CURVE448_PUB_KEY_SIZE; i++) {
263	0	out[i] = key->p[CURVE448_PUB_KEY_SIZE - i - 1];
264	0	}
265	0	}
266	0	else {
267	0	XMEMCPY(out, key->p, CURVE448_PUB_KEY_SIZE);
268	0	}
269	0	}
270
271	0	return ret;
272	0	}
273
274		#endif /* HAVE_CURVE448_KEY_EXPORT */
275
276		#ifdef HAVE_CURVE448_KEY_IMPORT
277
278		/* Import a curve448 public key from a byte array.
279		* Public key encoded in big-endian.
280		*
281		* in [in] Array holding public key.
282		* inLen [in] Number of bytes of data in array.
283		* key [in] Curve448 public key.
284		* returns BAD_FUNC_ARG when a parameter is NULL,
285		* ECC_BAD_ARG_E when inLen is less than CURVE448_PUB_KEY_SIZE,
286		* 0 otherwise.
287		*/
288		int wc_curve448_import_public(const byte* in, word32 inLen, curve448_key* key)
289	0	{
290	0	return wc_curve448_import_public_ex(in, inLen, key, EC448_BIG_ENDIAN);
291	0	}
292
293		/* Import a curve448 public key from a byte array.
294		*
295		* in [in] Array holding public key.
296		* inLen [in] Number of bytes of data in array.
297		* key [in] Curve448 public key.
298		* endian [in] Endianness of encoded number in byte array.
299		* returns BAD_FUNC_ARG when a parameter is NULL,
300		* ECC_BAD_ARG_E when inLen is less than CURVE448_PUB_KEY_SIZE,
301		* 0 otherwise.
302		*/
303		int wc_curve448_import_public_ex(const byte* in, word32 inLen,
304		curve448_key* key, int endian)
305	0	{
306	0	int ret = 0;
307	0	int i;
308
309		/* sanity check */
310	0	if ((key == NULL) \|\| (in == NULL)) {
311	0	ret = BAD_FUNC_ARG;
312	0	}
313
314		/* check size of incoming keys */
315	0	if ((ret == 0) && (inLen != CURVE448_PUB_KEY_SIZE)) {
316	0	ret = ECC_BAD_ARG_E;
317	0	}
318
319	0	if (ret == 0) {
320	0	if (endian == EC448_BIG_ENDIAN) {
321		/* read keys in Big Endian format */
322	0	for (i = 0; i < CURVE448_PUB_KEY_SIZE; i++) {
323	0	key->p[i] = in[CURVE448_PUB_KEY_SIZE - i - 1];
324	0	}
325	0	}
326	0	else
327	0	XMEMCPY(key->p, in, inLen);
328	0	key->pubSet = 1;
329	0	}
330
331	0	return ret;
332	0	}
333
334		/* Check the public key value (big or little endian)
335		*
336		* pub [in] Public key bytes.
337		* pubSz [in] Size of public key in bytes.
338		* endian [in] Public key bytes passed in as big-endian or little-endian.
339		* returns BAD_FUNC_ARGS when pub is NULL,
340		* ECC_BAD_ARG_E when key length is not 56 bytes, public key value is
341		* zero or one;
342		* BUFFER_E when size of public key is zero;
343		* 0 otherwise.
344		*/
345		int wc_curve448_check_public(const byte* pub, word32 pubSz, int endian)
346	0	{
347	0	int ret = 0;
348	0	word32 i;
349
350	0	if (pub == NULL) {
351	0	ret = BAD_FUNC_ARG;
352	0	}
353
354		/* Check for empty key data */
355	0	if ((ret == 0) && (pubSz == 0)) {
356	0	ret = BUFFER_E;
357	0	}
358
359		/* Check key length */
360	0	if ((ret == 0) && (pubSz != CURVE448_PUB_KEY_SIZE)) {
361	0	ret = ECC_BAD_ARG_E;
362	0	}
363
364	0	if (ret == 0) {
365	0	if (endian == EC448_LITTLE_ENDIAN) {
366		/* Check for value of zero or one */
367	0	for (i = CURVE448_PUB_KEY_SIZE - 1; i > 0; i--) {
368	0	if (pub[i] != 0) {
369	0	break;
370	0	}
371	0	}
372	0	if ((i == 0) && (pub[0] == 0 \|\| pub[0] == 1)) {
373	0	return ECC_BAD_ARG_E;
374	0	}
375		/* Check for order-1 or higher */
376	0	for (i = CURVE448_PUB_KEY_SIZE - 1; i > 28; i--) {
377	0	if (pub[i] != 0xff) {
378	0	break;
379	0	}
380	0	}
381	0	if ((i == 28) && (pub[i] == 0xff)) {
382	0	return ECC_BAD_ARG_E;
383	0	}
384	0	if ((i == 28) && (pub[i] == 0xfe)) {
385	0	for (--i; i > 0; i--) {
386	0	if (pub[i] != 0xff) {
387	0	break;
388	0	}
389	0	}
390	0	if ((i == 0) && (pub[i] >= 0xfe)) {
391	0	return ECC_BAD_ARG_E;
392	0	}
393	0	}
394	0	}
395	0	else {
396		/* Check for value of zero or one */
397	0	for (i = 0; i < CURVE448_PUB_KEY_SIZE-1; i++) {
398	0	if (pub[i] != 0) {
399	0	break;
400	0	}
401	0	}
402	0	if ((i == CURVE448_PUB_KEY_SIZE - 1) &&
403	0	(pub[i] == 0 \|\| pub[i] == 1)) {
404	0	ret = ECC_BAD_ARG_E;
405	0	}
406		/* Check for order-1 or higher */
407	0	for (i = 0; i < 27; i++) {
408	0	if (pub[i] != 0xff) {
409	0	break;
410	0	}
411	0	}
412	0	if ((i == 27) && (pub[i] == 0xff)) {
413	0	return ECC_BAD_ARG_E;
414	0	}
415	0	if ((i == 27) && (pub[i] == 0xfe)) {
416	0	for (++i; i < CURVE448_PUB_KEY_SIZE - 1; i--) {
417	0	if (pub[i] != 0xff) {
418	0	break;
419	0	}
420	0	}
421	0	if ((i == CURVE448_PUB_KEY_SIZE) && (pub[i] >= 0xfe)) {
422	0	return ECC_BAD_ARG_E;
423	0	}
424	0	}
425	0	}
426	0	}
427
428	0	return ret;
429	0	}
430
431		#endif /* HAVE_CURVE448_KEY_IMPORT */
432
433
434		#ifdef HAVE_CURVE448_KEY_EXPORT
435
436		/* Export the curve448 private key raw form.
437		* Private key encoded big-endian.
438		*
439		* key [in] Curve448 private key.
440		* out [in] Array to hold private key.
441		* outLen [in/out] On in, the number of bytes in array.
442		* On out, the number bytes put into array.
443		* returns BAD_FUNC_ARG when a parameter is NULL,
444		* ECC_BAD_ARG_E when outLen is less than CURVE448_KEY_SIZE,
445		* 0 otherwise.
446		*/
447		int wc_curve448_export_private_raw(curve448_key* key, byte* out, word32* outLen)
448	0	{
449	0	return wc_curve448_export_private_raw_ex(key, out, outLen,
450	0	EC448_BIG_ENDIAN);
451	0	}
452
453		/* Export the curve448 private key raw form.
454		*
455		* key [in] Curve448 private key.
456		* out [in] Array to hold private key.
457		* outLen [in/out] On in, the number of bytes in array.
458		* On out, the number bytes put into array.
459		* endian [in] Endianness to use when encoding number in array.
460		* returns BAD_FUNC_ARG when a parameter is NULL,
461		* ECC_BAD_ARG_E when outLen is less than CURVE448_KEY_SIZE,
462		* 0 otherwise.
463		*/
464		int wc_curve448_export_private_raw_ex(curve448_key* key, byte* out,
465		word32* outLen, int endian)
466	0	{
467	0	int ret = 0;
468	0	int i;
469
470		/* sanity check */
471	0	if ((key == NULL) \|\| (out == NULL) \|\| (outLen == NULL)) {
472	0	ret = BAD_FUNC_ARG;
473	0	}
474
475		/* check size of outgoing buffer */
476	0	if ((ret == 0) && (*outLen < CURVE448_KEY_SIZE)) {
477	0	*outLen = CURVE448_KEY_SIZE;
478	0	ret = ECC_BAD_ARG_E;
479	0	}
480	0	if (ret == 0) {
481	0	*outLen = CURVE448_KEY_SIZE;
482
483	0	if (endian == EC448_BIG_ENDIAN) {
484		/* put the key in Big Endian format */
485	0	for (i = 0; i < CURVE448_KEY_SIZE; i++) {
486	0	out[i] = key->k[CURVE448_KEY_SIZE - i - 1];
487	0	}
488	0	}
489	0	else {
490	0	XMEMCPY(out, key->k, CURVE448_KEY_SIZE);
491	0	}
492	0	}
493
494	0	return ret;
495	0	}
496
497		/* Export the curve448 private and public keys in raw form.
498		* Private and public key encoded big-endian.
499		*
500		* key [in] Curve448 private key.
501		* priv [in] Array to hold private key.
502		* privSz [in/out] On in, the number of bytes in private key array.
503		* On out, the number bytes put into private key array.
504		* pub [in] Array to hold public key.
505		* pubSz [in/out] On in, the number of bytes in public key array.
506		* On out, the number bytes put into public key array.
507		* returns BAD_FUNC_ARG when a parameter is NULL,
508		* ECC_BAD_ARG_E when privSz is less than CURVE448_KEY_SIZE or pubSz is
509		* less than CURVE448_PUB_KEY_SIZE,
510		* 0 otherwise.
511		*/
512		int wc_curve448_export_key_raw(curve448_key* key, byte* priv, word32 *privSz,
513		byte* pub, word32 *pubSz)
514	0	{
515	0	return wc_curve448_export_key_raw_ex(key, priv, privSz, pub, pubSz,
516	0	EC448_BIG_ENDIAN);
517	0	}
518
519		/* Export the curve448 private and public keys in raw form.
520		*
521		* key [in] Curve448 private key.
522		* priv [in] Array to hold private key.
523		* privSz [in/out] On in, the number of bytes in private key array.
524		* On out, the number bytes put into private key array.
525		* pub [in] Array to hold public key.
526		* pubSz [in/out] On in, the number of bytes in public key array.
527		* On out, the number bytes put into public key array.
528		* endian [in] Endianness to use when encoding number in array.
529		* returns BAD_FUNC_ARG when a parameter is NULL,
530		* ECC_BAD_ARG_E when privSz is less than CURVE448_KEY_SIZE or pubSz is
531		* less than CURVE448_PUB_KEY_SIZE,
532		* 0 otherwise.
533		*/
534		int wc_curve448_export_key_raw_ex(curve448_key* key, byte* priv, word32 *privSz,
535		byte* pub, word32 *pubSz, int endian)
536	0	{
537	0	int ret;
538
539		/* export private part */
540	0	ret = wc_curve448_export_private_raw_ex(key, priv, privSz, endian);
541	0	if (ret == 0) {
542		/* export public part */
543	0	ret = wc_curve448_export_public_ex(key, pub, pubSz, endian);
544	0	}
545
546	0	return ret;
547	0	}
548
549		#endif /* HAVE_CURVE448_KEY_EXPORT */
550
551		#ifdef HAVE_CURVE448_KEY_IMPORT
552
553		/* Import curve448 private and public keys from a byte arrays.
554		* Private and public keys encoded in big-endian.
555		*
556		* piv [in] Array holding private key.
557		* privSz [in] Number of bytes of data in private key array.
558		* pub [in] Array holding public key.
559		* pubSz [in] Number of bytes of data in public key array.
560		* key [in] Curve448 private/public key.
561		* returns BAD_FUNC_ARG when a parameter is NULL,
562		* ECC_BAD_ARG_E when privSz is less than CURVE448_KEY_SIZE or pubSz is
563		* less than CURVE448_PUB_KEY_SIZE,
564		* 0 otherwise.
565		*/
566		int wc_curve448_import_private_raw(const byte* priv, word32 privSz,
567		const byte* pub, word32 pubSz,
568		curve448_key* key)
569	0	{
570	0	return wc_curve448_import_private_raw_ex(priv, privSz, pub, pubSz, key,
571	0	EC448_BIG_ENDIAN);
572	0	}
573
574		/* Import curve448 private and public keys from a byte arrays.
575		*
576		* piv [in] Array holding private key.
577		* privSz [in] Number of bytes of data in private key array.
578		* pub [in] Array holding public key.
579		* pubSz [in] Number of bytes of data in public key array.
580		* key [in] Curve448 private/public key.
581		* endian [in] Endianness of encoded numbers in byte arrays.
582		* returns BAD_FUNC_ARG when a parameter is NULL,
583		* ECC_BAD_ARG_E when privSz is less than CURVE448_KEY_SIZE or pubSz is
584		* less than CURVE448_PUB_KEY_SIZE,
585		* 0 otherwise.
586		*/
587		int wc_curve448_import_private_raw_ex(const byte* priv, word32 privSz,
588		const byte* pub, word32 pubSz,
589		curve448_key* key, int endian)
590	0	{
591	0	int ret;
592
593		/* import private part */
594	0	ret = wc_curve448_import_private_ex(priv, privSz, key, endian);
595	0	if (ret == 0) {
596		/* import public part */
597	0	return wc_curve448_import_public_ex(pub, pubSz, key, endian);
598	0	}
599
600	0	return ret;
601	0	}
602
603		/* Import curve448 private key from a byte array.
604		* Private key encoded in big-endian.
605		*
606		* piv [in] Array holding private key.
607		* privSz [in] Number of bytes of data in private key array.
608		* key [in] Curve448 private/public key.
609		* returns BAD_FUNC_ARG when a parameter is NULL,
610		* ECC_BAD_ARG_E when privSz is less than CURVE448_KEY_SIZE,
611		* 0 otherwise.
612		*/
613		int wc_curve448_import_private(const byte* priv, word32 privSz,
614		curve448_key* key)
615	0	{
616	0	return wc_curve448_import_private_ex(priv, privSz, key, EC448_BIG_ENDIAN);
617	0	}
618
619		/* Import curve448 private key from a byte array.
620		*
621		* piv [in] Array holding private key.
622		* privSz [in] Number of bytes of data in private key array.
623		* key [in] Curve448 private/public key.
624		* endian [in] Endianness of encoded number in byte array.
625		* returns BAD_FUNC_ARG when a parameter is NULL,
626		* ECC_BAD_ARG_E when privSz is less than CURVE448_KEY_SIZE,
627		* 0 otherwise.
628		*/
629		int wc_curve448_import_private_ex(const byte* priv, word32 privSz,
630		curve448_key* key, int endian)
631	0	{
632	0	int ret = 0;
633	0	int i;
634
635		/* sanity check */
636	0	if ((key == NULL) \|\| (priv == NULL)) {
637	0	ret = BAD_FUNC_ARG;
638	0	}
639
640		/* check size of incoming keys */
641	0	if ((ret == 0) && ((int)privSz != CURVE448_KEY_SIZE)) {
642	0	ret = ECC_BAD_ARG_E;
643	0	}
644
645	0	if (ret == 0) {
646	0	if (endian == EC448_BIG_ENDIAN) {
647		/* read the key in Big Endian format */
648	0	for (i = 0; i < CURVE448_KEY_SIZE; i++) {
649	0	key->k[i] = priv[CURVE448_KEY_SIZE - i - 1];
650	0	}
651	0	}
652	0	else {
653	0	XMEMCPY(key->k, priv, CURVE448_KEY_SIZE);
654	0	}
655
656		/* Clamp the key */
657	0	key->k[0] &= 0xfc;
658	0	key->k[CURVE448_KEY_SIZE-1] \|= 0x80;
659
660	0	key->privSet = 1;
661	0	}
662
663	0	return ret;
664	0	}
665
666		#endif /* HAVE_CURVE448_KEY_IMPORT */
667
668
669		/* Initialize the curve448 key.
670		*
671		* key [in] Curve448 key object.
672		* returns BAD_FUNC_ARG when key is NULL,
673		* 0 otherwise.
674		*/
675		int wc_curve448_init(curve448_key* key)
676	0	{
677	0	int ret = 0;
678
679	0	if (key == NULL) {
680	0	ret = BAD_FUNC_ARG;
681	0	}
682
683	0	if (ret == 0) {
684	0	XMEMSET(key, 0, sizeof(*key));
685
686	0	fe448_init();
687
688		#ifdef WOLFSSL_CHECK_MEM_ZERO
689		wc_MemZero_Add("wc_curve448_init key->k", &key->k, CURVE448_KEY_SIZE);
690		#endif
691	0	}
692
693	0	return ret;
694	0	}
695
696
697		/* Clears the curve448 key data.
698		*
699		* key [in] Curve448 key object.
700		*/
701		void wc_curve448_free(curve448_key* key)
702	0	{
703	0	if (key != NULL) {
704	0	ForceZero(key->k, sizeof(key->k));
705	0	XMEMSET(key->p, 0, sizeof(key->p));
706	0	key->pubSet = 0;
707	0	key->privSet = 0;
708		#ifdef WOLFSSL_CHECK_MEM_ZERO
709		wc_MemZero_Check(key, sizeof(curve448_key));
710		#endif
711	0	}
712	0	}
713
714
715		/* Get the curve448 key's size.
716		*
717		* key [in] Curve448 key object.
718		* returns 0 if key is NULL,
719		* CURVE448_KEY_SIZE otherwise.
720		*/
721		int wc_curve448_size(curve448_key* key)
722	0	{
723	0	int ret = 0;
724
725	0	if (key != NULL) {
726	0	ret = CURVE448_KEY_SIZE;
727	0	}
728
729	0	return ret;
730	0	}
731
732		#endif /* HAVE_CURVE448 */
733