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Import libgcrypt 1.5.3.

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This commit is contained in:
Vladimir Serbinenko 2013-11-07 06:35:50 +01:00
parent c12936c5d1
commit d1307d873a
72 changed files with 11732 additions and 2916 deletions
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22
grub-core/lib/libgcrypt/mpi/mpi-pow.c
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@ -1,6 +1,7 @@
/* mpi-pow.c - MPI functions for exponentiation
* Copyright (C) 1994, 1996, 1998, 2000, 2002
* 2003 Free Software Foundation, Inc.
* 2013 g10 Code GmbH
*
* This file is part of Libgcrypt.
*
@ -81,9 +82,14 @@ gcry_mpi_powm (gcry_mpi_t res,
if (!esize)
{
/* Exponent is zero, result is 1 mod MOD, i.e., 1 or 0 depending
on if MOD equals 1. */
rp[0] = 1;
on if MOD equals 1. */
res->nlimbs = (msize == 1 && mod->d[0] == 1) ? 0 : 1;
if (res->nlimbs)
{
RESIZE_IF_NEEDED (res, 1);
rp = res->d;
rp[0] = 1;
}
res->sign = 0;
goto leave;
}
@ -230,7 +236,13 @@ gcry_mpi_powm (gcry_mpi_t res,
tp = rp; rp = xp; xp = tp;
rsize = xsize;
if ( (mpi_limb_signed_t)e < 0 )
/* To mitigate the Yarom/Falkner flush+reload cache
* side-channel attack on the RSA secret exponent, we do
* the multiplication regardless of the value of the
* high-bit of E. But to avoid this performance penalty
* we do it only if the exponent has been stored in secure
* memory and we can thus assume it is a secret exponent. */
if (esec || (mpi_limb_signed_t)e < 0)
{
/*mpih_mul( xp, rp, rsize, bp, bsize );*/
if( bsize < KARATSUBA_THRESHOLD )
@ -245,7 +257,9 @@ gcry_mpi_powm (gcry_mpi_t res,
_gcry_mpih_divrem(xp + msize, 0, xp, xsize, mp, msize);
xsize = msize;
}
}
if ( (mpi_limb_signed_t)e < 0 )
{
tp = rp; rp = xp; xp = tp;
rsize = xsize;
}