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annotate libtommath/bn_mp_tc_div_2d.c @ 1689:d2d3b5ba6c64

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update travis to Ubuntu focal to provide chacha20
author Matt Johnston <matt@ucc.asn.au>
date Tue, 26 May 2020 23:13:48 +0800
parents f52919ffd3b1
children
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1655
f52919ffd3b1 update ltm to 1.1.0 and enable FIPS 186.4 compliant key-generation (#79)
Steffen Jaeckel <s_jaeckel@gmx.de>
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1 #include "tommath_private.h"
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2 #ifdef BN_MP_TC_DIV_2D_C
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3 /* LibTomMath, multiple-precision integer library -- Tom St Denis
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4 *
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5 * LibTomMath is a library that provides multiple-precision
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6 * integer arithmetic as well as number theoretic functionality.
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7 *
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8 * The library was designed directly after the MPI library by
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9 * Michael Fromberger but has been written from scratch with
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10 * additional optimizations in place.
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11 *
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12 * SPDX-License-Identifier: Unlicense
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13 */
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14
f52919ffd3b1 update ltm to 1.1.0 and enable FIPS 186.4 compliant key-generation (#79)
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15 /* two complement right shift */
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16 int mp_tc_div_2d(const mp_int *a, int b, mp_int *c)
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17 {
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18 int res;
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19 if (mp_isneg(a) == MP_NO) {
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20 return mp_div_2d(a, b, c, NULL);
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21 }
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22
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23 res = mp_add_d(a, 1uL, c);
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24 if (res != MP_OKAY) {
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25 return res;
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26 }
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27
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28 res = mp_div_2d(c, b, c, NULL);
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29 return (res == MP_OKAY) ? mp_sub_d(c, 1uL, c) : res;
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30 }
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31 #endif
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32
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33 /* ref: HEAD -> master, tag: v1.1.0 */
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34 /* git commit: 08549ad6bc8b0cede0b357a9c341c5c6473a9c55 */
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35 /* commit time: 2019-01-28 20:32:32 +0100 */