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
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
142
d29b64170cf0 import of libtommath 0.32
Matt Johnston <matt@ucc.asn.au>
parents: 2
diff changeset
1 #include <tommath.h>
d29b64170cf0 import of libtommath 0.32
Matt Johnston <matt@ucc.asn.au>
parents: 2
diff changeset
2 #ifdef BN_MP_PRIME_IS_DIVISIBLE_C
2
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
3 /* LibTomMath, multiple-precision integer library -- Tom St Denis
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
4 *
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
5 * LibTomMath is a library that provides multiple-precision
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
6 * integer arithmetic as well as number theoretic functionality.
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
7 *
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
8 * The library was designed directly after the MPI library by
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
9 * Michael Fromberger but has been written from scratch with
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
10 * additional optimizations in place.
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
11 *
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
12 * The library is free for all purposes without any express
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
13 * guarantee it works.
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
14 *
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
15 * Tom St Denis, [email protected], http://math.libtomcrypt.org
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
16 */
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
17
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
18 /* determines if an integers is divisible by one
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
19 * of the first PRIME_SIZE primes or not
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
20 *
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
21 * sets result to 0 if not, 1 if yes
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
22 */
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
23 int mp_prime_is_divisible (mp_int * a, int *result)
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
24 {
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
25 int err, ix;
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
26 mp_digit res;
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
27
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
28 /* default to not */
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
29 *result = MP_NO;
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
30
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
31 for (ix = 0; ix < PRIME_SIZE; ix++) {
190
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents: 142
diff changeset
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
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
34 return err;
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
35 }
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
36
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
37 /* is the residue zero? */
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
38 if (res == 0) {
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
39 *result = MP_YES;
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
40 return MP_OKAY;
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
41 }
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
42 }
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
43
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
44 return MP_OKAY;
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
45 }
142
d29b64170cf0 import of libtommath 0.32
Matt Johnston <matt@ucc.asn.au>
parents: 2
diff changeset
46 #endif