56 lines
1.3 KiB
C
56 lines
1.3 KiB
C
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#include <tommath.h>
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#ifdef BN_MP_READ_UNSIGNED_BIN_C
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/* LibTomMath, multiple-precision integer library -- Tom St Denis
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*
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* LibTomMath is a library that provides multiple-precision
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* integer arithmetic as well as number theoretic functionality.
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*
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* The library was designed directly after the MPI library by
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* Michael Fromberger but has been written from scratch with
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* additional optimizations in place.
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*
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* The library is free for all purposes without any express
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* guarantee it works.
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*
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* Tom St Denis, tomstdenis@gmail.com, http://libtom.org
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*/
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/* reads a unsigned char array, assumes the msb is stored first [big endian] */
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int mp_read_unsigned_bin (mp_int * a, const unsigned char *b, int c)
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{
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int res;
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/* make sure there are at least two digits */
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if (a->alloc < 2) {
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if ((res = mp_grow(a, 2)) != MP_OKAY) {
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return res;
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}
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}
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/* zero the int */
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mp_zero (a);
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/* read the bytes in */
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while (c-- > 0) {
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if ((res = mp_mul_2d (a, 8, a)) != MP_OKAY) {
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return res;
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}
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#ifndef MP_8BIT
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a->dp[0] |= *b++;
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a->used += 1;
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#else
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a->dp[0] = (*b & MP_MASK);
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a->dp[1] |= ((*b++ >> 7U) & 1);
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a->used += 2;
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#endif
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}
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mp_clamp (a);
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return MP_OKAY;
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}
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#endif
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/* $Source$ */
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/* $Revision: 0.41 $ */
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/* $Date: 2007-04-18 09:58:18 +0000 $ */
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