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progs/perftest.c: Use from Glibc syscall numbers.
[catacomb] / math / mpbarrett-mexp.c
CommitLineData
ab0350a6 1/* -*-c-*-
2 *
ab0350a6 3 * Multiple simultaneous exponentiations
4 *
5 * (c) 1999 Straylight/Edgeware
6 */
7
45c0fd36 8/*----- Licensing notice --------------------------------------------------*
ab0350a6 9 *
10 * This file is part of Catacomb.
11 *
12 * Catacomb is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU Library General Public License as
14 * published by the Free Software Foundation; either version 2 of the
15 * License, or (at your option) any later version.
45c0fd36 16 *
ab0350a6 17 * Catacomb is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU Library General Public License for more details.
45c0fd36 21 *
ab0350a6 22 * You should have received a copy of the GNU Library General Public
23 * License along with Catacomb; if not, write to the Free
24 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
25 * MA 02111-1307, USA.
26 */
27
ab0350a6 28/*----- Header files ------------------------------------------------------*/
29
30#include "mp.h"
31#include "mpbarrett.h"
32
33#define EXP_WINSZ 3
34#include "mpbarrett-exp.h"
35
36/*----- Main code ---------------------------------------------------------*/
37
38/* --- @mpbarrett_mexp@ --- *
39 *
295f4f90 40 * Arguments: @const mpbarrett *mb@ = pointer to Barrett reduction context
ab0350a6 41 * @mp *d@ = fake destination
34e4f738 42 * @const mp_expfactor *f@ = pointer to array of factors
ab0350a6 43 * @size_t n@ = number of factors supplied
44 *
45 * Returns: If the bases are %$g_0, g_1, \ldots, g_{n-1}$% and the
46 * exponents are %$e_0, e_1, \ldots, e_{n-1}$% then the result
47 * is:
48 *
49 * %$g_0^{e_0} g_1^{e_1} \ldots g_{n-1}^{e_{n-1}} \bmod m$%
50 */
51
295f4f90
MW		 52mp *mpbarrett_mexp(const mpbarrett *mb, mp *d,
53 const mp_expfactor *f, size_t n)
ab0350a6 54{
34e4f738 55 mp_expfactor *ff = xmalloc(n * sizeof(mp_expfactor));
ab0350a6 56 mp *a = MP_ONE;
57 mp *spare;
34e4f738 58 mp *g = MP_NEW;
ab0350a6 59 size_t i;
60
61 spare = MP_NEW;
62 for (i = 0; i < n; i++) {
34e4f738 63 if (f[i].exp->f & MP_BURN)
ab0350a6 64 spare = MP_NEWSEC;
a69a3efd 65 if (MP_NEGP(f[i].exp))
b817bfc6 66 ff[i].base = mp_modinv(MP_NEW, f[i].base, mb->m);
a69a3efd 67 else
68 ff[i].base = MP_COPY(f[i].base);
34e4f738 69 ff[i].exp = f[i].exp;
ab0350a6 70 }
34e4f738 71 mp_drop(g);
72 EXP_SIMUL(a, ff, n);
ab0350a6 73 mp_drop(d);
74 mp_drop(spare);
34e4f738 75 for (i = 0; i < n; i++)
76 mp_drop(ff[i].base);
77 xfree(ff);
ab0350a6 78 return (a);
79}
80
81/*----- Test rig ----------------------------------------------------------*/
82
83#ifdef TEST_RIG
84
85#include <mLib/testrig.h>
86
87static int verify(size_t n, dstr *v)
88{
89 mp *m = *(mp **)v[0].buf;
90 mp_expfactor *f = xmalloc(n * sizeof(*f));
91 mp *r, *rr;
92 size_t i, j;
93 mpbarrett mb;
94 int ok = 1;
95
96 j = 1;
97 for (i = 0; i < n; i++) {
98 f[i].base = *(mp **)v[j++].buf;
99 f[i].exp = *(mp **)v[j++].buf;
100 }
101
102 rr = *(mp **)v[j].buf;
103 mpbarrett_create(&mb, m);
104 r = mpbarrett_mexp(&mb, MP_NEW, f, n);
105 if (!MP_EQ(r, rr)) {
106 fputs("\n*** mexp failed\n", stderr);
107 fputs("m = ", stderr); mp_writefile(m, stderr, 10);
108 for (i = 0; i < n; i++) {
bb77b1d1 109 fprintf(stderr, "\ng_%lu = ", (unsigned long)i);
ab0350a6 110 mp_writefile(f[i].base, stderr, 10);
bb77b1d1 111 fprintf(stderr, "\ne_%lu = ", (unsigned long)i);
ab0350a6 112 mp_writefile(f[i].exp, stderr, 10);
113 }
114 fputs("\nr = ", stderr); mp_writefile(r, stderr, 10);
115 fputs("\nR = ", stderr); mp_writefile(rr, stderr, 10);
116 fputc('\n', stderr);
117 ok = 0;
118 }
119
120 for (i = 0; i < n; i++) {
121 MP_DROP(f[i].base);
122 MP_DROP(f[i].exp);
123 }
124 MP_DROP(m);
125 MP_DROP(r);
126 MP_DROP(rr);
127 mpbarrett_destroy(&mb);
128 assert(mparena_count(MPARENA_GLOBAL) == 0);
129 return (ok);
130}
131
132static int t1(dstr *v) { return verify(1, v); }
133static int t2(dstr *v) { return verify(2, v); }
134static int t3(dstr *v) { return verify(3, v); }
135static int t4(dstr *v) { return verify(4, v); }
136static int t5(dstr *v) { return verify(5, v); }
137
138static test_chunk tests[] = {
139 { "mexp-1", t1, { &type_mp,
140 &type_mp, &type_mp,
141 &type_mp, 0 } },
142 { "mexp-2", t2, { &type_mp,
143 &type_mp, &type_mp,
144 &type_mp, &type_mp,
145 &type_mp, 0 } },
146 { "mexp-3", t3, { &type_mp,
147 &type_mp, &type_mp,
148 &type_mp, &type_mp,
149 &type_mp, &type_mp,
150 &type_mp, 0 } },
151 { "mexp-4", t4, { &type_mp,
152 &type_mp, &type_mp,
153 &type_mp, &type_mp,
154 &type_mp, &type_mp,
155 &type_mp, &type_mp,
156 &type_mp, 0 } },
157 { "mexp-5", t5, { &type_mp,
158 &type_mp, &type_mp,
159 &type_mp, &type_mp,
160 &type_mp, &type_mp,
161 &type_mp, &type_mp,
162 &type_mp, &type_mp,
163 &type_mp, 0 } },
164 { 0, 0, { 0 } }
165};
166
167int main(int argc, char *argv[])
168{
169 sub_init();
0f00dc4c 170 test_run(argc, argv, tests, SRCDIR "/t/mpbarrett");
ab0350a6 171 return (0);
45c0fd36 172}
ab0350a6 173
174#endif
175
176/*----- That's all, folks -------------------------------------------------*/
Catacomb cryptographic library