Mercurial > dropbear
annotate bn_mp_prime_is_divisible.c @ 190:d8254fc979e9 libtommath-orig LTM_0.35
Initial import of libtommath 0.35
| author | Matt Johnston <matt@ucc.asn.au> |
|---|---|
| date | Fri, 06 May 2005 08:59:30 +0000 |
| parents | d29b64170cf0 |
| children |
| rev | line source |
|---|---|
| 142 | 1 #include <tommath.h> |
| 2 #ifdef BN_MP_PRIME_IS_DIVISIBLE_C | |
| 2 | 3 /* LibTomMath, multiple-precision integer library -- Tom St Denis |
| 4 * | |
| 5 * LibTomMath is a library that provides multiple-precision | |
| 6 * integer arithmetic as well as number theoretic functionality. | |
| 7 * | |
| 8 * The library was designed directly after the MPI library by | |
| 9 * Michael Fromberger but has been written from scratch with | |
| 10 * additional optimizations in place. | |
| 11 * | |
| 12 * The library is free for all purposes without any express | |
| 13 * guarantee it works. | |
| 14 * | |
| 15 * Tom St Denis, [email protected], http://math.libtomcrypt.org | |
| 16 */ | |
| 17 | |
| 18 /* determines if an integers is divisible by one | |
| 19 * of the first PRIME_SIZE primes or not | |
| 20 * | |
| 21 * sets result to 0 if not, 1 if yes | |
| 22 */ | |
| 23 int mp_prime_is_divisible (mp_int * a, int *result) | |
| 24 { | |
| 25 int err, ix; | |
| 26 mp_digit res; | |
| 27 | |
| 28 /* default to not */ | |
| 29 *result = MP_NO; | |
| 30 | |
| 31 for (ix = 0; ix < PRIME_SIZE; ix++) { | |
|
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d8254fc979e9
Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
142
diff
changeset
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32 /* what is a mod LBL_prime_tab[ix] */ |
|
d8254fc979e9
Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
142
diff
changeset
|
33 if ((err = mp_mod_d (a, ltm_prime_tab[ix], &res)) != MP_OKAY) { |
| 2 | 34 return err; |
| 35 } | |
| 36 | |
| 37 /* is the residue zero? */ | |
| 38 if (res == 0) { | |
| 39 *result = MP_YES; | |
| 40 return MP_OKAY; | |
| 41 } | |
| 42 } | |
| 43 | |
| 44 return MP_OKAY; | |
| 45 } | |
| 142 | 46 #endif |