arne
/
cryptopp
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Reverted to previous SafeConvert code. Its not as efficient as it could be, but it is darn sure correct. Self-tests for the verification to follow

pull/35/head
Jeffrey Walton 2015-07-30 08:38:28 -04:00
parent e507a4136e
commit 33e6a62c5e
1 changed files with 2 additions and 21 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

23
misc.h
View File

@ -59,6 +59,7 @@
# pragma GCC diagnostic ignored "-Wunused-value" # pragma GCC diagnostic ignored "-Wunused-value"
# pragma GCC diagnostic ignored "-Wunused-variable" # pragma GCC diagnostic ignored "-Wunused-variable"
# pragma GCC diagnostic ignored "-Wunused-parameter" # pragma GCC diagnostic ignored "-Wunused-parameter"
# pragma GCC diagnostic ignored "-Wtype-limit"
#endif #endif
NAMESPACE_BEGIN(CryptoPP) NAMESPACE_BEGIN(CryptoPP)
@ -245,8 +246,6 @@ template <class T> inline const T& STDMIN(const T& a, const T& b)
template <class T1, class T2> inline const T1 UnsignedMin(const T1& a, const T2& b) template <class T1, class T2> inline const T1 UnsignedMin(const T1& a, const T2& b)
{ {
CRYPTOPP_COMPILE_ASSERT((sizeof(T1)<=sizeof(T2) && T2(-1)>0) || (sizeof(T1)>sizeof(T2) && T1(-1)>0)); CRYPTOPP_COMPILE_ASSERT((sizeof(T1)<=sizeof(T2) && T2(-1)>0) || (sizeof(T1)>sizeof(T2) && T1(-1)>0));
CRYPTOPP_ASSERT(a==0 || a>0); // GCC workaround: get rid of the warning "comparison is always true due to limited range of data type"
CRYPTOPP_ASSERT(b>=0);
if (sizeof(T1)<=sizeof(T2)) if (sizeof(T1)<=sizeof(T2))
return b < (T2)a ? (T1)b : a; return b < (T2)a ? (T1)b : a;
@ -369,27 +368,9 @@ inline T Crop(T value, size_t size)
template <class T1, class T2> template <class T1, class T2>
inline bool SafeConvert(T1 from, T2 &to) inline bool SafeConvert(T1 from, T2 &to)
{ {
// Original code: always perform the assignment
to = (T2)from; to = (T2)from;
if (from != to || (from > 0) != (to > 0))
// Check for sign difference
if(std::numeric_limits<T1>::is_signed ^ std::numeric_limits<T2>::is_signed)
{
// Handle T1 is signed
if(std::numeric_limits<T1>::is_signed && from < 0)
return false;
// Fall through for T1 is unsigned
}
// Handle unsigned greater
if(!std::numeric_limits<T1>::is_signed && from > static_cast<T1>(std::numeric_limits<T2>::max())) {
return false; return false;
}
// Handle signed less
else if(from < static_cast<T1>(std::numeric_limits<T2>::min())) {
return false;
}
return true; return true;
} }