ecmult.h

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/***********************************************************************
 * Copyright (c) 2013, 2014, 2017 Pieter Wuille, Andrew Poelstra       *
 * Distributed under the MIT software license, see the accompanying    *
 * file COPYING or https://www.opensource.org/licenses/mit-license.php.*
 ***********************************************************************/
 
#ifndef SECP256K1_ECMULT_H
#define SECP256K1_ECMULT_H
 
#include "group.h"
#include "scalar.h"
#include "scratch.h"
 
#ifndef ECMULT_WINDOW_SIZE
#  define ECMULT_WINDOW_SIZE 15
#  ifdef DEBUG_CONFIG
#     pragma message DEBUG_CONFIG_MSG("ECMULT_WINDOW_SIZE undefined, assuming default value")
#  endif
#endif
 
#ifdef DEBUG_CONFIG
#  pragma message DEBUG_CONFIG_DEF(ECMULT_WINDOW_SIZE)
#endif
 
/* Noone will ever need more than a window size of 24. The code might
 * be correct for larger values of ECMULT_WINDOW_SIZE but this is not
 * tested.
 *
 * The following limitations are known, and there are probably more:
 * If WINDOW_G > 27 and size_t has 32 bits, then the code is incorrect
 * because the size of the memory object that we allocate (in bytes)
 * will not fit in a size_t.
 * If WINDOW_G > 31 and int has 32 bits, then the code is incorrect
 * because certain expressions will overflow.
 */
#if ECMULT_WINDOW_SIZE < 2 || ECMULT_WINDOW_SIZE > 24
#  error Set ECMULT_WINDOW_SIZE to an integer in range [2..24].
#endif

#define ECMULT_TABLE_SIZE(w) (1L << ((w)-2))

static void secp256k1_ecmult(secp256k1_gej *r, const secp256k1_gej *a, const secp256k1_scalar *na, const secp256k1_scalar *ng);
 
typedef int (secp256k1_ecmult_multi_callback)(secp256k1_scalar *sc, secp256k1_ge *pt, size_t idx, void *data);

static int secp256k1_ecmult_multi_var(const secp256k1_callback* error_callback, secp256k1_scratch *scratch, secp256k1_gej *r, const secp256k1_scalar *inp_g_sc, secp256k1_ecmult_multi_callback cb, void *cbdata, size_t n);
 
#endif /* SECP256K1_ECMULT_H */