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1 #include <tommath.h> |
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2 #ifdef BN_MP_REDUCE_SETUP_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.com |
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16 */ |
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17 |
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18 /* pre-calculate the value required for Barrett reduction |
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19 * For a given modulus "b" it calulates the value required in "a" |
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20 */ |
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21 int mp_reduce_setup (mp_int * a, mp_int * b) |
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22 { |
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23 int res; |
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24 |
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25 if ((res = mp_2expt (a, b->used * 2 * DIGIT_BIT)) != MP_OKAY) { |
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26 return res; |
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27 } |
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28 return mp_div (a, b, a, NULL); |
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29 } |
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30 #endif |
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31 |
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32 /* $Source: /cvs/libtom/libtommath/bn_mp_reduce_setup.c,v $ */ |
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33 /* $Revision: 1.3 $ */ |
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34 /* $Date: 2006/03/31 14:18:44 $ */ |
