view libtommath/bn_mp_read_signed_bin.c @ 421:dbb607d72d01 channel-fix

propagate from branch 'au.asn.ucc.matt.dropbear' (head eac2a177021cfa0cbf365d5821fe6c8a0a5dc758) to branch 'au.asn.ucc.matt.dropbear.channel-fix' (head be0d837816e2e985c7b2d80614d5df3496028e94)
author Matt Johnston <matt@ucc.asn.au>
date Sun, 11 Feb 2007 10:46:57 +0000
parents 5ff8218bcee9
children 60fc6476e044
line wrap: on
line source

#include <tommath.h>
#ifdef BN_MP_READ_SIGNED_BIN_C
/* LibTomMath, multiple-precision integer library -- Tom St Denis
 *
 * LibTomMath is a library that provides multiple-precision
 * integer arithmetic as well as number theoretic functionality.
 *
 * The library was designed directly after the MPI library by
 * Michael Fromberger but has been written from scratch with
 * additional optimizations in place.
 *
 * The library is free for all purposes without any express
 * guarantee it works.
 *
 * Tom St Denis, [email protected], http://math.libtomcrypt.com
 */

/* read signed bin, big endian, first byte is 0==positive or 1==negative */
int mp_read_signed_bin (mp_int * a, const unsigned char *b, int c)
{
  int     res;

  /* read magnitude */
  if ((res = mp_read_unsigned_bin (a, b + 1, c - 1)) != MP_OKAY) {
    return res;
  }

  /* first byte is 0 for positive, non-zero for negative */
  if (b[0] == 0) {
     a->sign = MP_ZPOS;
  } else {
     a->sign = MP_NEG;
  }

  return MP_OKAY;
}
#endif

/* $Source: /cvs/libtom/libtommath/bn_mp_read_signed_bin.c,v $ */
/* $Revision: 1.4 $ */
/* $Date: 2006/03/31 14:18:44 $ */