Mercurial > dropbear

annotate libtommath/bn_mp_xor.c @ 368:ed910547d449

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Free x component of DSS key upon failure to load (found by Klocwork)
author Matt Johnston <matt@ucc.asn.au>
date Thu, 02 Nov 2006 14:49:20 +0000
parents eed26cff980b
children 5ff8218bcee9
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284
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1 #include <tommath.h>
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2 #ifdef BN_MP_XOR_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 * The library is free for all purposes without any express
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13 * guarantee it works.
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14 *
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15 * Tom St Denis, [email protected], http://math.libtomcrypt.org
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16 */
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17
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18 /* XOR two ints together */
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19 int
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20 mp_xor (mp_int * a, mp_int * b, mp_int * c)
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21 {
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22 int res, ix, px;
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23 mp_int t, *x;
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24
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25 if (a->used > b->used) {
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26 if ((res = mp_init_copy (&t, a)) != MP_OKAY) {
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27 return res;
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28 }
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29 px = b->used;
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30 x = b;
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31 } else {
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32 if ((res = mp_init_copy (&t, b)) != MP_OKAY) {
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33 return res;
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34 }
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35 px = a->used;
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36 x = a;
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37 }
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38
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39 for (ix = 0; ix < px; ix++) {
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40 t.dp[ix] ^= x->dp[ix];
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41 }
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42 mp_clamp (&t);
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43 mp_exch (c, &t);
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44 mp_clear (&t);
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45 return MP_OKAY;
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46 }
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47 #endif