CMake/Source/cmCryptoHash.cxx
Brad King 293a7f4e2a cmCryptoHash: Provide factory "New" method
Construct a cmCryptoHash subclass instance based on the name of the
desired hash algorithm.
2011-11-16 10:15:44 -05:00

131 lines
4.3 KiB
C++

/*============================================================================
CMake - Cross Platform Makefile Generator
Copyright 2000-2009 Kitware, Inc., Insight Software Consortium
Distributed under the OSI-approved BSD License (the "License");
see accompanying file Copyright.txt for details.
This software is distributed WITHOUT ANY WARRANTY; without even the
implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the License for more information.
============================================================================*/
#include "cmCryptoHash.h"
#include <cmsys/MD5.h>
#include "cm_sha2.h"
//----------------------------------------------------------------------------
cmsys::auto_ptr<cmCryptoHash> cmCryptoHash::New(const char* algo)
{
if(strcmp(algo,"MD5") == 0)
{ return cmsys::auto_ptr<cmCryptoHash>(new cmCryptoHashMD5); }
else if(strcmp(algo,"SHA1") == 0)
{ return cmsys::auto_ptr<cmCryptoHash>(new cmCryptoHashSHA1); }
else if(strcmp(algo,"SHA224") == 0)
{ return cmsys::auto_ptr<cmCryptoHash>(new cmCryptoHashSHA224); }
else if(strcmp(algo,"SHA256") == 0)
{ return cmsys::auto_ptr<cmCryptoHash>(new cmCryptoHashSHA256); }
else if(strcmp(algo,"SHA384") == 0)
{ return cmsys::auto_ptr<cmCryptoHash>(new cmCryptoHashSHA384); }
else if(strcmp(algo,"SHA512") == 0)
{ return cmsys::auto_ptr<cmCryptoHash>(new cmCryptoHashSHA512); }
else
{ return cmsys::auto_ptr<cmCryptoHash>(0); }
}
//----------------------------------------------------------------------------
std::string cmCryptoHash::HashString(const char* input)
{
this->Initialize();
this->Append(reinterpret_cast<unsigned char const*>(input),
static_cast<int>(strlen(input)));
return this->Finalize();
}
//----------------------------------------------------------------------------
std::string cmCryptoHash::HashFile(const char* file)
{
std::ifstream fin(file, std::ios::in | cmsys_ios_binary);
if(!fin)
{
return "";
}
this->Initialize();
// Should be efficient enough on most system:
const int bufferSize = 4096;
char buffer[bufferSize];
unsigned char const* buffer_uc =
reinterpret_cast<unsigned char const*>(buffer);
// This copy loop is very sensitive on certain platforms with
// slightly broken stream libraries (like HPUX). Normally, it is
// incorrect to not check the error condition on the fin.read()
// before using the data, but the fin.gcount() will be zero if an
// error occurred. Therefore, the loop should be safe everywhere.
while(fin)
{
fin.read(buffer, bufferSize);
if(int gcount = static_cast<int>(fin.gcount()))
{
this->Append(buffer_uc, gcount);
}
}
if(fin.eof())
{
return this->Finalize();
}
return "";
}
//----------------------------------------------------------------------------
cmCryptoHashMD5::cmCryptoHashMD5(): MD5(cmsysMD5_New())
{
}
//----------------------------------------------------------------------------
cmCryptoHashMD5::~cmCryptoHashMD5()
{
cmsysMD5_Delete(this->MD5);
}
//----------------------------------------------------------------------------
void cmCryptoHashMD5::Initialize()
{
cmsysMD5_Initialize(this->MD5);
}
//----------------------------------------------------------------------------
void cmCryptoHashMD5::Append(unsigned char const* buf, int sz)
{
cmsysMD5_Append(this->MD5, buf, sz);
}
//----------------------------------------------------------------------------
std::string cmCryptoHashMD5::Finalize()
{
char md5out[32];
cmsysMD5_FinalizeHex(this->MD5, md5out);
return std::string(md5out, 32);
}
#define cmCryptoHash_SHA_CLASS_IMPL(SHA) \
cmCryptoHash##SHA::cmCryptoHash##SHA(): SHA(new SHA_CTX) {} \
cmCryptoHash##SHA::~cmCryptoHash##SHA() { delete this->SHA; } \
void cmCryptoHash##SHA::Initialize() { SHA##_Init(this->SHA); } \
void cmCryptoHash##SHA::Append(unsigned char const* buf, int sz) \
{ SHA##_Update(this->SHA, buf, sz); } \
std::string cmCryptoHash##SHA::Finalize() \
{ \
char out[SHA##_DIGEST_STRING_LENGTH]; \
SHA##_End(this->SHA, out); \
return std::string(out, SHA##_DIGEST_STRING_LENGTH-1); \
}
cmCryptoHash_SHA_CLASS_IMPL(SHA1)
cmCryptoHash_SHA_CLASS_IMPL(SHA224)
cmCryptoHash_SHA_CLASS_IMPL(SHA256)
cmCryptoHash_SHA_CLASS_IMPL(SHA384)
cmCryptoHash_SHA_CLASS_IMPL(SHA512)