44 lines
1.1 KiB
C
44 lines
1.1 KiB
C
/* LibTomMath, multiple-precision integer library -- Tom St Denis
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*
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* LibTomMath is library that provides for multiple-precision
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* integer arithmetic as well as number theoretic functionality.
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*
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* The library is 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@iahu.ca, http://libtommath.iahu.ca
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*/
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#include <tommath.h>
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/* store in unsigned [big endian] format */
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int
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mp_to_unsigned_bin (mp_int * a, unsigned char *b)
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{
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int x, res;
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mp_int t;
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if ((res = mp_init_copy (&t, a)) != MP_OKAY) {
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return res;
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}
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x = 0;
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while (mp_iszero (&t) == 0) {
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if (DIGIT_BIT != 7) {
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b[x++] = (unsigned char) (t.dp[0] & 255);
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} else {
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b[x++] = (unsigned char) (t.dp[0] | ((t.dp[1] & 0x01) << 7));
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}
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if ((res = mp_div_2d (&t, 8, &t, NULL)) != MP_OKAY) {
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mp_clear (&t);
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return res;
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}
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}
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bn_reverse (b, x);
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mp_clear (&t);
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return MP_OKAY;
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}
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