Bitcoin Core 29.99.0
P2P Digital Currency
precompute_ecmult.c
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1/*****************************************************************************************************
2 * Copyright (c) 2013, 2014, 2017, 2021 Pieter Wuille, Andrew Poelstra, Jonas Nick, Russell O'Connor *
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#include <inttypes.h>
8#include <stdio.h>
9#include <stdlib.h>
10
11#include "../include/secp256k1.h"
12
13#include "assumptions.h"
14#include "util.h"
15
16#include "field_impl.h"
17#include "group_impl.h"
18#include "int128_impl.h"
19#include "ecmult.h"
21
22static void print_table(FILE *fp, const char *name, int window_g, const secp256k1_ge_storage* table) {
23 int j;
24 int i;
25
26 fprintf(fp, "const secp256k1_ge_storage %s[ECMULT_TABLE_SIZE(WINDOW_G)] = {\n", name);
27 fprintf(fp, " S(%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32
28 ",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32")\n",
30
31 j = 1;
32 for(i = 3; i <= window_g; ++i) {
33 fprintf(fp, "#if WINDOW_G > %d\n", i-1);
34 for(;j < ECMULT_TABLE_SIZE(i); ++j) {
35 fprintf(fp, ",S(%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32
36 ",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32",%"PRIx32")\n",
38 }
39 fprintf(fp, "#endif\n");
40 }
41 fprintf(fp, "};\n");
42}
43
44static void print_two_tables(FILE *fp, int window_g) {
45 secp256k1_ge_storage* table = malloc(ECMULT_TABLE_SIZE(window_g) * sizeof(secp256k1_ge_storage));
46 secp256k1_ge_storage* table_128 = malloc(ECMULT_TABLE_SIZE(window_g) * sizeof(secp256k1_ge_storage));
47
49
50 print_table(fp, "secp256k1_pre_g", window_g, table);
51 print_table(fp, "secp256k1_pre_g_128", window_g, table_128);
52
53 free(table);
54 free(table_128);
55}
56
57int main(void) {
58 /* Always compute all tables for window sizes up to 15. */
59 int window_g = (ECMULT_WINDOW_SIZE < 15) ? 15 : ECMULT_WINDOW_SIZE;
60 const char outfile[] = "src/precomputed_ecmult.c";
61 FILE* fp;
62
63 fp = fopen(outfile, "w");
64 if (fp == NULL) {
65 fprintf(stderr, "Could not open %s for writing!\n", outfile);
66 return EXIT_FAILURE;
67 }
68
69 fprintf(fp, "/* This file was automatically generated by precompute_ecmult. */\n");
70 fprintf(fp, "/* This file contains an array secp256k1_pre_g with odd multiples of the base point G and\n");
71 fprintf(fp, " * an array secp256k1_pre_g_128 with odd multiples of 2^128*G for accelerating the computation of a*P + b*G.\n");
72 fprintf(fp, " */\n");
73 fprintf(fp, "#include \"group.h\"\n");
74 fprintf(fp, "#include \"ecmult.h\"\n");
75 fprintf(fp, "#include \"precomputed_ecmult.h\"\n");
76 fprintf(fp, "#define S(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p) SECP256K1_GE_STORAGE_CONST(0x##a##u,0x##b##u,0x##c##u,0x##d##u,0x##e##u,0x##f##u,0x##g##u,0x##h##u,0x##i##u,0x##j##u,0x##k##u,0x##l##u,0x##m##u,0x##n##u,0x##o##u,0x##p##u)\n");
77 fprintf(fp, "#if ECMULT_WINDOW_SIZE > %d\n", window_g);
78 fprintf(fp, " #error configuration mismatch, invalid ECMULT_WINDOW_SIZE. Try deleting precomputed_ecmult.c before the build.\n");
79 fprintf(fp, "#endif\n");
80 fprintf(fp, "#ifdef EXHAUSTIVE_TEST_ORDER\n");
81 fprintf(fp, "# error Cannot compile precomputed_ecmult.c in exhaustive test mode\n");
82 fprintf(fp, "#endif /* EXHAUSTIVE_TEST_ORDER */\n");
83 fprintf(fp, "#define WINDOW_G ECMULT_WINDOW_SIZE\n");
84
85 print_two_tables(fp, window_g);
86
87 fprintf(fp, "#undef S\n");
88 fclose(fp);
89
90 return EXIT_SUCCESS;
91}
return EXIT_SUCCESS
#define ECMULT_TABLE_SIZE(w)
The number of entries a table with precomputed multiples needs to have.
Definition: ecmult.h:41
#define ECMULT_WINDOW_SIZE
Definition: ecmult.h:15
static void secp256k1_ecmult_compute_two_tables(secp256k1_ge_storage *table, secp256k1_ge_storage *table_128, int window_g, const secp256k1_ge *gen)
#define SECP256K1_GE_STORAGE_CONST_GET(t)
Definition: group.h:45
static const secp256k1_ge secp256k1_ge_const_g
Definition: group_impl.h:72
FILE * fopen(const fs::path &p, const char *mode)
Definition: fs.cpp:26
static void print_two_tables(FILE *fp, int window_g)
int main(void)
static void print_table(FILE *fp, const char *name, int window_g, const secp256k1_ge_storage *table)
const char * name
Definition: rest.cpp:49