/*
 Derived from source code of TrueCrypt 7.1a, which is
 Copyright (c) 2008-2012 TrueCrypt Developers Association and which is governed
 by the TrueCrypt License 3.0.

 Modifications and additions to the original source code (contained in this file) 
 and all other portions of this file are Copyright (c) 2013-2015 IDRIX
 and are governed by the Apache License 2.0 the full text of which is
 contained in the file License.txt included in VeraCrypt binary and source
 code distribution packages.
*/

#include "VolumePassword.h"
#include "Platform/SerializerFactory.h"
#include "Platform/StringConverter.h"

namespace VeraCrypt
{
	VolumePassword::VolumePassword () : PasswordSize (0), Unportable (false)
	{
		AllocateBuffer ();
	}

	VolumePassword::VolumePassword (const char *password, size_t size)
	{
		Set ((const byte *) password, size);
	}

	VolumePassword::VolumePassword (const byte *password, size_t size)
	{
		Set (password, size);
	}

	VolumePassword::VolumePassword (const wchar_t *password, size_t charCount)
	{
		Set (password, charCount);
	}

	VolumePassword::VolumePassword (const wstring &password)
	{
		Set (password.c_str(), password.size());
	}

	VolumePassword::~VolumePassword ()
	{
	}

	void VolumePassword::AllocateBuffer ()
	{
		if (!PasswordBuffer.IsAllocated ())
			PasswordBuffer.Allocate (MaxSize);
	}

	void VolumePassword::CheckPortability () const
	{
		if (Unportable || !IsPortable())
			throw UnportablePassword (SRC_POS);
	}

	void VolumePassword::Deserialize (shared_ptr <Stream> stream)
	{
		Serializer sr (stream);
		uint64 passwordSize;
		sr.Deserialize ("PasswordSize", passwordSize);
		PasswordSize = static_cast <size_t> (passwordSize);
		sr.Deserialize ("PasswordBuffer", BufferPtr (PasswordBuffer));
		
		Buffer wipeBuffer (128 * 1024);
		sr.Deserialize ("WipeData", wipeBuffer);
	}

	bool VolumePassword::IsPortable () const
	{
		for (size_t i = 0; i < PasswordSize; i++)
		{
			if (PasswordBuffer[i] >= 0x7f || PasswordBuffer[i] < 0x20)
				return false;
		}
		return true;
	}

	void VolumePassword::Serialize (shared_ptr <Stream> stream) const
	{
		Serializable::Serialize (stream);
		Serializer sr (stream);
		sr.Serialize ("PasswordSize", static_cast <uint64> (PasswordSize));
		sr.Serialize ("PasswordBuffer", ConstBufferPtr (PasswordBuffer));

		// Wipe password from an eventual pipe buffer
		Buffer wipeBuffer (128 * 1024);
		wipeBuffer.Zero();
		sr.Serialize ("WipeData", ConstBufferPtr (wipeBuffer));
	}

	void VolumePassword::Set (const byte *password, size_t size)
	{
		AllocateBuffer ();
		
		if (size > MaxSize)
			throw PasswordTooLong (SRC_POS);
		
		PasswordBuffer.CopyFrom (ConstBufferPtr (password, size));
		PasswordSize = size;

		Unportable = !IsPortable();
	}
	
	void VolumePassword::Set (const wchar_t *password, size_t charCount)
	{
		if (charCount > MaxSize)
			throw PasswordTooLong (SRC_POS);

		union Conv
		{
			byte b[sizeof (wchar_t)];
			wchar_t c;
		};

		Conv conv;
		conv.c = L'A';
		
		int lsbPos = -1;
		for (size_t i = 0; i < sizeof (conv.b); ++i)
		{
			if (conv.b[i] == L'A')
			{
				lsbPos = i;
				break;
			}
		}

		if (lsbPos == -1)
			throw ParameterIncorrect (SRC_POS);

		bool unportable = false;
		byte passwordBuf[MaxSize];
		for (size_t i = 0; i < charCount; ++i)
		{
			conv.c = password[i];
			passwordBuf[i] = conv.b[lsbPos];
			for (int j = 0; j < (int) sizeof (wchar_t); ++j)
			{
				if (j != lsbPos && conv.b[j] != 0)
					unportable = true;
			}
		}
		
		Set (passwordBuf, charCount);
		
		if (unportable)
			Unportable = true;
	}

	void VolumePassword::Set (const ConstBufferPtr &password)
	{
		Set (password, password.Size());
	}
	
	void VolumePassword::Set (const VolumePassword &password)
	{
		Set (password.DataPtr(), password.Size());
	}

	TC_SERIALIZER_FACTORY_ADD_CLASS (VolumePassword);

#define TC_EXCEPTION(TYPE) TC_SERIALIZER_FACTORY_ADD(TYPE)
#undef TC_EXCEPTION_NODECL
#define TC_EXCEPTION_NODECL(TYPE) TC_SERIALIZER_FACTORY_ADD(TYPE)

	TC_SERIALIZER_FACTORY_ADD_EXCEPTION_SET (PasswordException);
}
