diff options
Diffstat (limited to 'mpi/mpi-pow.c')
| -rw-r--r-- | mpi/mpi-pow.c | 21 |
1 files changed, 17 insertions, 4 deletions
diff --git a/mpi/mpi-pow.c b/mpi/mpi-pow.c index a57eff87a..e0bed13ac 100644 --- a/mpi/mpi-pow.c +++ b/mpi/mpi-pow.c @@ -1,6 +1,6 @@ /* mpi-pow.c - MPI functions * Copyright (C) 1998 Free Software Foundation, Inc. - * Copyright (C) 1994, 1996 Free Software Foundation, Inc. + * Copyright (C) 1994, 1996, 2000 Free Software Foundation, Inc. * * This file is part of GnuPG. * @@ -30,9 +30,10 @@ #include <config.h> #include <stdio.h> #include <stdlib.h> -#include <assert.h> +#include <string.h> #include "mpi-internal.h" #include "longlong.h" +#include <assert.h> /**************** @@ -159,7 +160,9 @@ gcry_mpi_powm( MPI res, MPI base, MPI exp, MPI mod) int c; mpi_limb_t e; mpi_limb_t carry_limb; + struct karatsuba_ctx karactx; + memset( &karactx, 0, sizeof karactx ); negative_result = (ep[0] & 1) && base->sign; i = esize - 1; @@ -177,6 +180,7 @@ gcry_mpi_powm( MPI res, MPI base, MPI exp, MPI mod) * by RP (==RES->d), and with 50% probability in the area originally * pointed to by XP. */ + for(;;) { while( c ) { mpi_ptr_t tp; @@ -194,7 +198,6 @@ gcry_mpi_powm( MPI res, MPI base, MPI exp, MPI mod) mpi_free_limb_space( tspace ); tsize = 2 * rsize; tspace = mpi_alloc_limb_space( tsize, 0 ); - } mpih_sqr_n( xp, rp, rsize, tspace ); } @@ -209,7 +212,15 @@ gcry_mpi_powm( MPI res, MPI base, MPI exp, MPI mod) rsize = xsize; if( (mpi_limb_signed_t)e < 0 ) { - mpihelp_mul( xp, rp, rsize, bp, bsize ); + /*mpihelp_mul( xp, rp, rsize, bp, bsize );*/ + if( bsize < KARATSUBA_THRESHOLD ) { + mpihelp_mul( xp, rp, rsize, bp, bsize ); + } + else { + mpihelp_mul_karatsuba_case( + xp, rp, rsize, bp, bsize, &karactx ); + } + xsize = rsize + bsize; if( xsize > msize ) { mpihelp_divrem(xp + msize, 0, xp, xsize, mp, msize); @@ -258,6 +269,8 @@ gcry_mpi_powm( MPI res, MPI base, MPI exp, MPI mod) if( mod_shift_cnt ) mpihelp_rshift( rp, rp, rsize, mod_shift_cnt); MPN_NORMALIZE (rp, rsize); + + mpihelp_release_karatsuba_ctx( &karactx ); } if( negative_result && rsize ) { |