示例#1
0
//Decrypt from Input Buffer to Output Buffer
//Returns false if n is multiple of 8
void BlowFish::Decrypt(const unsigned char* in, unsigned char* out, unsigned int n, int iMode)
{
	//Check the buffer's length - should be > 0 and multiple of 8
	if((n==0)||(n%8!=0))
		//throw exception("Incorrect buffer length");
		return;

	SBlock work;
	if(iMode == CBC) //CBC mode, using the Chain
	{
		SBlock crypt, chain(m_oChain);
		for(; n >= 8; n -= 8, in += 8)
		{
			BytesToBlock(in, work);
			crypt = work;
			Decrypt(work);
			work ^= chain;
			chain = crypt;
			BlockToBytes(work, out+=8);
		}
	}
	else if(iMode == CFB) //CFB mode, using the Chain, not using Decrypt()
	{
		SBlock crypt, chain(m_oChain);
		for(; n >= 8; n -= 8, in += 8)
		{
			BytesToBlock(in, work);
			Encrypt(chain);
			crypt = work;
			work ^= chain;
			chain = crypt;
			BlockToBytes(work, out+=8);
		}
	}
	else //ECB mode, not using the Chain
	{
		for(; n >= 8; n -= 8, in += 8)
		{
			BytesToBlock(in, work);
			Decrypt(work);
			BlockToBytes(work, out+=8);
		}
	}
}
示例#2
0
//Decrypt Buffer in Place
//Returns false if n is multiple of 8
void CBlowFish::Decrypt(unsigned char* buf, size_t n, int iMode)
{
    //Check the buffer's length - should be > 0 and multiple of 8
    if((n==0)||(n%8!=0))
        throw std::exception("Incorrect buffer length");
    SBlock work;
    if(iMode == CBC) //CBC mode, using the Chain
    {
        SBlock crypt, chain(m_oChain);
        for(; n >= 8; n -= 8)
        {
            BytesToBlock(buf, work);
            crypt = work;
            Decrypt(work);
            work ^= chain;
            chain = crypt;
            BlockToBytes(work, buf+=8);
        }
    }
    else if(iMode == CFB) //CFB mode, using the Chain, not using Decrypt()
    {
        SBlock crypt, chain(m_oChain);
        for(; n >= 8; n -= 8)
        {
            BytesToBlock(buf, work);
            Encrypt(chain);
            crypt = work;
            work ^= chain;
            chain = crypt;
            BlockToBytes(work, buf+=8);
        }
    }
    else //ECB mode, not using the Chain
    {
        for(; n >= 8; n -= 8)
        {
            BytesToBlock(buf, work);
            Decrypt(work);
            BlockToBytes(work, buf+=8);
        }
    }
}
示例#3
0
//Encrypt Buffer in Place
//Returns false if n is multiple of 8
void BlowFish::Encrypt(unsigned char* buf, unsigned int n, int iMode)
{
	//Check the buffer's length - should be > 0 and multiple of 8
	if((n==0)||(n%8!=0))
		//throw exception("Incorrect buffer length");
		return;

	SBlock work;
	if(iMode == CBC) //CBC mode, using the Chain
	{
		SBlock chain(m_oChain);
		for(; n >= 8; n -= 8)
		{
			BytesToBlock(buf, work);
			work ^= chain;
			Encrypt(work);
			chain = work;
			BlockToBytes(work, buf+=8);
		}
	}
	else if(iMode == CFB) //CFB mode, using the Chain
	{
		SBlock chain(m_oChain);
		for(; n >= 8; n -= 8)
		{
			Encrypt(chain);
			BytesToBlock(buf, work);
			work ^= chain;
			chain = work;
			BlockToBytes(work, buf+=8);
		}
	}
	else //ECB mode, not using the Chain
	{
		for(; n >= 8; n -= 8)
		{
			BytesToBlock(buf, work);
			Encrypt(work);
			BlockToBytes(work, buf+=8);
		}
	}
}