Mercurial > dropbear

annotate bn_mp_dr_setup.c @ 19:e1037a1e12e7 libtommath-orig

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
0.30 release of LibTomMath
author Matt Johnston <matt@ucc.asn.au>
date Tue, 15 Jun 2004 14:42:57 +0000
parents 86e0b50a9b58
children d29b64170cf0
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
2
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
1 /* LibTomMath, multiple-precision integer library -- Tom St Denis
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
2 *
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
3 * LibTomMath is a library that provides multiple-precision
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
4 * integer arithmetic as well as number theoretic functionality.
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
5 *
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
6 * 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
7 * Michael Fromberger but has been written from scratch with
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
8 * additional optimizations in place.
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
9 *
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
10 * 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
11 * guarantee it works.
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
12 *
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
13 * Tom St Denis, [email protected], http://math.libtomcrypt.org
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 #include <tommath.h>
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 /* determines the setup value */
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
18 void mp_dr_setup(mp_int *a, mp_digit *d)
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
19 {
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
20 /* the casts are required if DIGIT_BIT is one less than
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
21 * the number of bits in a mp_digit [e.g. DIGIT_BIT==31]
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 *d = (mp_digit)((((mp_word)1) << ((mp_word)DIGIT_BIT)) -
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
24 ((mp_word)a->dp[0]));
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
25 }
86e0b50a9b58 ltm 0.30 orig import
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
26