tommath/bn_mp_to_unsigned_bin.c

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#include <tommath_private.h>
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#ifdef BN_MP_TO_UNSIGNED_BIN_C
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/* LibTomMath, multiple-precision integer library -- Tom St Denis
*
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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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* The library was designed directly after the MPI library by
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* Michael Fromberger but has been written from scratch with
* additional optimizations in place.
*
* The library is free for all purposes without any express
* guarantee it works.
*
* Tom St Denis, tstdenis82@gmail.com, http://libtom.org
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*/
/* store in unsigned [big endian] format */
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int mp_to_unsigned_bin(const mp_int *a, unsigned char *b)
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{
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int x, res;
mp_int t;
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if ((res = mp_init_copy(&t, a)) != MP_OKAY) {
return res;
}
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x = 0;
while (mp_iszero(&t) == MP_NO) {
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#ifndef MP_8BIT
b[x++] = (unsigned char)(t.dp[0] & 255);
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#else
b[x++] = (unsigned char)(t.dp[0] | ((t.dp[1] & 0x01) << 7));
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#endif
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if ((res = mp_div_2d(&t, 8, &t, NULL)) != MP_OKAY) {
mp_clear(&t);
return res;
}
}
bn_reverse(b, x);
mp_clear(&t);
return MP_OKAY;
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}
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#endif
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/* ref: $Format:%D$ */
/* git commit: $Format:%H$ */
/* commit time: $Format:%ai$ */