Mercurial > dropbear

annotate bn_mp_reduce_2k_setup_l.c @ 190:d8254fc979e9 libtommath-orig LTM_0.35

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Initial import of libtommath 0.35
author Matt Johnston <matt@ucc.asn.au>
date Fri, 06 May 2005 08:59:30 +0000
parents
children 97db060d0ef5
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
190
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
1 #include <tommath.h>
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
2 #ifdef BN_MP_REDUCE_2K_SETUP_L_C
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
3 /* LibTomMath, multiple-precision integer library -- Tom St Denis
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
4 *
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
5 * LibTomMath is a library that provides multiple-precision
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
6 * integer arithmetic as well as number theoretic functionality.
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
7 *
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
8 * The library was designed directly after the MPI library by
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
9 * Michael Fromberger but has been written from scratch with
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
10 * additional optimizations in place.
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
11 *
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
12 * The library is free for all purposes without any express
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
13 * guarantee it works.
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
14 *
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
15 * Tom St Denis, [email protected], http://math.libtomcrypt.org
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
16 */
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
17
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
18 /* determines the setup value */
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
19 int mp_reduce_2k_setup_l(mp_int *a, mp_int *d)
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
20 {
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
21 int res;
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
22 mp_int tmp;
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
23
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
24 if ((res = mp_init(&tmp)) != MP_OKAY) {
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
25 return res;
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
26 }
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
27
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
28 if ((res = mp_2expt(&tmp, mp_count_bits(a))) != MP_OKAY) {
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
29 goto ERR;
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
30 }
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
31
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
32 if ((res = s_mp_sub(&tmp, a, d)) != MP_OKAY) {
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
33 goto ERR;
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
34 }
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
35
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
36 ERR:
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
37 mp_clear(&tmp);
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
38 return res;
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
39 }
d8254fc979e9 Initial import of libtommath 0.35
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
40 #endif