source: box/trunk/lib/crypto/CipherAES.cpp @ 217

// --------------------------------------------------------------------------
//
// File
//              Name:    CipherAES.cpp
//              Purpose: AES cipher description
//              Created: 27/4/04
//
// --------------------------------------------------------------------------

#include "Box.h"

// Only available in new versions of openssl
#ifndef HAVE_OLD_SSL

#include <openssl/evp.h>

#define BOX_LIB_CRYPTO_OPENSSL_HEADERS_INCLUDED_TRUE

#include "CipherAES.h"
#include "CipherException.h"

#include "MemLeakFindOn.h"


// --------------------------------------------------------------------------
//
// Function
//              Name:    CipherAES::CipherAES(CipherDescription::CipherMode, const void *, unsigned int, const void *)
//              Purpose: Constructor -- note key material and IV are not copied. KeyLength in bytes.
//              Created: 27/4/04
//
// --------------------------------------------------------------------------
CipherAES::CipherAES(CipherDescription::CipherMode Mode, const void *pKey, unsigned int KeyLength, const void *pInitialisationVector)
        : CipherDescription(),
          mMode(Mode),
          mpKey(pKey),
          mKeyLength(KeyLength),
          mpInitialisationVector(pInitialisationVector)
{
}


// --------------------------------------------------------------------------
//
// Function
//              Name:    CipherAES::CipherAES(const CipherAES &)
//              Purpose: Copy constructor
//              Created: 27/4/04
//
// --------------------------------------------------------------------------
CipherAES::CipherAES(const CipherAES &rToCopy)
        : CipherDescription(rToCopy),
          mMode(rToCopy.mMode),
          mpKey(rToCopy.mpKey),
          mKeyLength(rToCopy.mKeyLength),
          mpInitialisationVector(rToCopy.mpInitialisationVector)
{
}


// --------------------------------------------------------------------------
//
// Function
//              Name:    ~CipherAES::CipherAES()
//              Purpose: Destructor
//              Created: 27/4/04
//
// --------------------------------------------------------------------------
CipherAES::~CipherAES()
{
}



// --------------------------------------------------------------------------
//
// Function
//              Name:    CipherAES::operator=(const CipherAES &)
//              Purpose: Assignment operator
//              Created: 27/4/04
//
// --------------------------------------------------------------------------
CipherAES &CipherAES::operator=(const CipherAES &rToCopy)
{
        CipherDescription::operator=(rToCopy);

        mMode = rToCopy.mMode;
        mpKey = rToCopy.mpKey;
        mKeyLength = rToCopy.mKeyLength;
        mpInitialisationVector = rToCopy.mpInitialisationVector;

        return *this;
}


// --------------------------------------------------------------------------
//
// Function
//              Name:    CipherAES::GetCipher()
//              Purpose: Returns cipher object
//              Created: 27/4/04
//
// --------------------------------------------------------------------------
const EVP_CIPHER *CipherAES::GetCipher() const
{
        switch(mMode)
        {
        case CipherDescription::Mode_ECB:
                switch(mKeyLength)
                {
                        case (128/8): return EVP_aes_128_ecb(); break;
                        case (192/8): return EVP_aes_192_ecb(); break;
                        case (256/8): return EVP_aes_256_ecb(); break;
                default:
                        THROW_EXCEPTION(CipherException, EVPBadKeyLength)
                        break;
                }
                break;
        
        case CipherDescription::Mode_CBC:
                switch(mKeyLength)
                {
                        case (128/8): return EVP_aes_128_cbc(); break;
                        case (192/8): return EVP_aes_192_cbc(); break;
                        case (256/8): return EVP_aes_256_cbc(); break;
                default:
                        THROW_EXCEPTION(CipherException, EVPBadKeyLength)
                        break;
                }
                break;
        
        default:
                break;
        }

        // Unknown!
        THROW_EXCEPTION(CipherException, UnknownCipherMode)
}

// --------------------------------------------------------------------------
//
// Function
//              Name:    CipherAES::SetupParameters(EVP_CIPHER_CTX *)
//              Purpose: Set up various parameters for cipher
//              Created: 27/4/04
//
// --------------------------------------------------------------------------
void CipherAES::SetupParameters(EVP_CIPHER_CTX *pCipherContext) const
{
        ASSERT(pCipherContext != 0);
        
        // Set key (key length is implied)
        if(EVP_CipherInit_ex(pCipherContext, NULL, NULL, (unsigned char*)mpKey, (unsigned char*)mpInitialisationVector, -1) != 1)
        {
                THROW_EXCEPTION(CipherException, EVPInitFailure)
        }
        
}



#endif // n HAVE_OLD_SSL