Bitcoin Core  22.99.0
P2P Digital Currency
ecmult.h
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1 /***********************************************************************
2  * Copyright (c) 2013, 2014, 2017 Pieter Wuille, Andrew Poelstra *
3  * Distributed under the MIT software license, see the accompanying *
4  * file COPYING or https://www.opensource.org/licenses/mit-license.php.*
5  ***********************************************************************/
6 
7 #ifndef SECP256K1_ECMULT_H
8 #define SECP256K1_ECMULT_H
9 
10 #include "group.h"
11 #include "scalar.h"
12 #include "scratch.h"
13 
14 /* Noone will ever need more than a window size of 24. The code might
15  * be correct for larger values of ECMULT_WINDOW_SIZE but this is not
16  * tested.
17  *
18  * The following limitations are known, and there are probably more:
19  * If WINDOW_G > 27 and size_t has 32 bits, then the code is incorrect
20  * because the size of the memory object that we allocate (in bytes)
21  * will not fit in a size_t.
22  * If WINDOW_G > 31 and int has 32 bits, then the code is incorrect
23  * because certain expressions will overflow.
24  */
25 #if ECMULT_WINDOW_SIZE < 2 || ECMULT_WINDOW_SIZE > 24
26 # error Set ECMULT_WINDOW_SIZE to an integer in range [2..24].
27 #endif
28 
30 #define ECMULT_TABLE_SIZE(w) (1L << ((w)-2))
31 
33 static void secp256k1_ecmult(secp256k1_gej *r, const secp256k1_gej *a, const secp256k1_scalar *na, const secp256k1_scalar *ng);
34 
35 typedef int (secp256k1_ecmult_multi_callback)(secp256k1_scalar *sc, secp256k1_ge *pt, size_t idx, void *data);
36 
48 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);
49 
50 #endif /* SECP256K1_ECMULT_H */
scratch.h
group.h
secp256k1_scratch_space_struct
Definition: scratch.h:12
secp256k1_ecmult
static void secp256k1_ecmult(secp256k1_gej *r, const secp256k1_gej *a, const secp256k1_scalar *na, const secp256k1_scalar *ng)
Double multiply: R = na*A + ng*G.
secp256k1_scalar
A scalar modulo the group order of the secp256k1 curve.
Definition: scalar_4x64.h:13
secp256k1_gej
A group element of the secp256k1 curve, in jacobian coordinates.
Definition: group.h:23
secp256k1_ecmult_multi_var
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)
Multi-multiply: R = inp_g_sc * G + sum_i ni * Ai.
scalar.h
secp256k1_callback
Definition: util.h:19
secp256k1_ecmult_multi_callback
int() secp256k1_ecmult_multi_callback(secp256k1_scalar *sc, secp256k1_ge *pt, size_t idx, void *data)
Definition: ecmult.h:35
secp256k1_ge
A group element of the secp256k1 curve, in affine coordinates.
Definition: group.h:13