35 lines
874 B
C
35 lines
874 B
C
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/* 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://math.libtomcrypt.org
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*/
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#include <tommath.h>
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/* determines if a number is a valid DR modulus */
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int mp_dr_is_modulus(mp_int *a)
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{
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int ix;
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/* must be at least two digits */
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if (a->used < 2) {
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return 0;
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}
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for (ix = 1; ix < a->used; ix++) {
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if (a->dp[ix] != MP_MASK) {
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return 0;
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}
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}
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return 1;
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}
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