From 50e5c14c18671726d23479b5e0cadc4224100259 Mon Sep 17 00:00:00 2001 From: Jeffrey Walton Date: Thu, 7 Apr 2016 19:20:33 -0400 Subject: [PATCH] Improve constant propagation of fix for Issue 146 --- rijndael.cpp | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/rijndael.cpp b/rijndael.cpp index 92f9dea..ab9f70a 100644 --- a/rijndael.cpp +++ b/rijndael.cpp @@ -388,10 +388,12 @@ void Rijndael::Enc::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock t3 = rk[7]; rk += 8; - // timing attack countermeasure. see comments at top for more details + // timing attack countermeasure. see comments at top for more details. + // also see http://github.com/weidai11/cryptopp/issues/146 const int cacheLineSize = GetCacheLineSize(); unsigned int i; - volatile word32 u = 0; + volatile word32 _u = 0; + word32 u = _u; #if defined(CRYPTOPP_ALLOW_UNALIGNED_DATA_ACCESS) || defined(CRYPTOPP_ALLOW_RIJNDAEL_UNALIGNED_DATA_ACCESS) for (i=0; i<2048; i+=cacheLineSize) #else @@ -464,10 +466,12 @@ void Rijndael::Dec::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock t3 = rk[7]; rk += 8; - // timing attack countermeasure. see comments at top for more details + // timing attack countermeasure. see comments at top for more details. + // also see http://github.com/weidai11/cryptopp/issues/146 const int cacheLineSize = GetCacheLineSize(); unsigned int i; - volatile word32 u = 0; + volatile word32 _u = 0; + word32 u = _u; #if defined(CRYPTOPP_ALLOW_UNALIGNED_DATA_ACCESS) || defined(CRYPTOPP_ALLOW_RIJNDAEL_UNALIGNED_DATA_ACCESS) for (i=0; i<2048; i+=cacheLineSize) #else