/* ed25519.h
 *
 * Copyright (C) 2006-2017 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
 */


#ifndef WOLF_CRYPT_ED25519_H
# define WOLF_CRYPT_ED25519_H

# include <wolfssl/wolfcrypt/types.h>

# ifdef HAVE_ED25519

#  include <wolfssl/wolfcrypt/fe_operations.h>
#  include <wolfssl/wolfcrypt/ge_operations.h>
#  include <wolfssl/wolfcrypt/random.h>
#  include <wolfssl/wolfcrypt/sha512.h>

#  ifdef WOLFSSL_ASYNC_CRYPT
#   include <wolfssl/wolfcrypt/async.h>
#  endif

#  ifdef __cplusplus
extern "C" {
#  endif


/* info about EdDSA curve specifically ed25519, defined as an elliptic curve
 * over GF(p) */

/*
 *  32,                key size
 *  "ED25519",         curve name
 *  "2^255-19",        prime number
 *  "SHA512",          hash function
 *  "-121665/121666",  value of d
 */

#  define ED25519_KEY_SIZE     32 /* private key only */
#  define ED25519_SIG_SIZE     64

#  define ED25519_PUB_KEY_SIZE 32 /* compressed */
/* both private and public key */
#  define ED25519_PRV_KEY_SIZE (ED25519_PUB_KEY_SIZE + ED25519_KEY_SIZE)


#  ifndef WC_ED25519KEY_TYPE_DEFINED
typedef struct ed25519_key ed25519_key;
#   define WC_ED25519KEY_TYPE_DEFINED
#  endif

/* An ED25519 Key */
struct ed25519_key {
    byte         p[ED25519_PUB_KEY_SIZE]; /* compressed public key */
    byte         k[ED25519_PRV_KEY_SIZE]; /* private key : 32 secret -- 32 public */
    #  ifdef FREESCALE_LTC_ECC
    /* uncompressed point coordinates */
    byte         pointX[ED25519_KEY_SIZE]; /* recovered X coordinate */
    byte         pointY[ED25519_KEY_SIZE]; /* Y coordinate is the public key with The most significant bit of the final octet always zero. */
    #  endif
    #  ifdef WOLFSSL_ASYNC_CRYPT
    WC_ASYNC_DEV asyncDev;
    #  endif
};


WOLFSSL_API
int
wc_ed25519_make_key(WC_RNG * rng, int keysize, ed25519_key * key);
WOLFSSL_API
int
wc_ed25519_sign_msg(const byte * in, word32 inlen, byte * out,
  word32 * outlen, ed25519_key * key);
WOLFSSL_API
int
wc_ed25519_verify_msg(const byte * sig, word32 siglen, const byte * msg,
  word32 msglen, int * stat, ed25519_key * key);
WOLFSSL_API
int
wc_ed25519_init(ed25519_key * key);
WOLFSSL_API
void
wc_ed25519_free(ed25519_key * key);
WOLFSSL_API
int
wc_ed25519_import_public(const byte * in, word32 inLen, ed25519_key * key);
WOLFSSL_API
int
wc_ed25519_import_private_only(const byte * priv, word32 privSz,
  ed25519_key * key);
WOLFSSL_API
int
wc_ed25519_import_private_key(const byte * priv, word32 privSz,
  const byte * pub, word32 pubSz, ed25519_key * key);
WOLFSSL_API
int
wc_ed25519_export_public(ed25519_key *, byte * out, word32 * outLen);
WOLFSSL_API
int
wc_ed25519_export_private_only(ed25519_key * key, byte * out, word32 * outLen);
WOLFSSL_API
int
wc_ed25519_export_private(ed25519_key * key, byte * out, word32 * outLen);
WOLFSSL_API
int
wc_ed25519_export_key(ed25519_key * key,
  byte * priv, word32 * privSz,
  byte * pub, word32 * pubSz);

int
wc_ed25519_check_key(ed25519_key * key);

/* size helper */
WOLFSSL_API
int
wc_ed25519_size(ed25519_key * key);
WOLFSSL_API
int
wc_ed25519_priv_size(ed25519_key * key);
WOLFSSL_API
int
wc_ed25519_pub_size(ed25519_key * key);
WOLFSSL_API
int
wc_ed25519_sig_size(ed25519_key * key);

#  ifdef __cplusplus
} /* extern "C" */
#  endif

# endif /* HAVE_ED25519 */
#endif  /* WOLF_CRYPT_ED25519_H */
