// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
// Mobius Forensic Toolkit
// Copyright (C) 2008,2009,2010,2011,2012,2013,2014,2015,2016,2017,2018,2019,2020 Eduardo Aguiar
//
// This program is free software; you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by the
// Free Software Foundation; either version 2, or (at your option) any later
// version.
//
// This program is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General
// Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
#include "cipher_info.h"
#include <mobius/exception.inc>
#include <cstdint>
#include <map>
#include <stdexcept>
#include <string>

namespace mobius
{
namespace os
{
namespace win
{
namespace dpapi
{
namespace
{
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Cipher information map
//! \see https://docs.microsoft.com/en-us/windows/desktop/seccrypto/alg-id
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
struct cipher_info
{
  std::string id;		// crypt::cipher cipher_id
  std::uint32_t key_length;	// key length in bytes
  std::uint32_t block_length;	// block length in bytes
  std::uint32_t iv_length;	// IV length in bytes
};

static const std::map <std::uint32_t, cipher_info> CIPHERS =
{
  {0x6601, {"des", 8, 8, 8}},
  {0x6603, {"3des", 24, 8, 8}},
  {0x660e, {"aes", 16, 16, 16}},
  {0x660f, {"aes", 24, 16, 16}},
  {0x6610, {"aes", 32, 16, 16}},
  {0x6801, {"rc4", 16, 8, 16}}
};

} // namespace

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Get cipher ID by MS alg ID
//! \param ms_alg_id MS alg ID
//! \return mobius::crypt::cipher ID
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
std::string
get_cipher_id (std::uint32_t ms_alg_id)
{
  auto iter = CIPHERS.find (ms_alg_id);
  
  if (iter != CIPHERS.end ())
    return iter->second.id;
  
  else
    throw std::invalid_argument (MOBIUS_EXCEPTION_MSG ("Unknown MS alg ID"));
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Get cipher key length by MS alg ID
//! \param ms_alg_id MS alg ID
//! \return Key length in bytes
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
std::uint32_t
get_cipher_key_length (std::uint32_t ms_alg_id)
{
  auto iter = CIPHERS.find (ms_alg_id);
  
  if (iter != CIPHERS.end ())
    return iter->second.key_length;
  
  else
    throw std::invalid_argument (MOBIUS_EXCEPTION_MSG ("Unknown MS alg ID"));
}

// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
//! \brief Get cipher salt length by MS alg ID
//! \param ms_alg_id MS alg ID
//! \return Salt length in bytes
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
std::uint32_t
get_cipher_salt_length (std::uint32_t ms_alg_id)
{
  auto iter = CIPHERS.find (ms_alg_id);
  
  if (iter != CIPHERS.end ())
    return iter->second.iv_length;
  
  else
    throw std::invalid_argument (MOBIUS_EXCEPTION_MSG ("Unknown MS alg ID"));
}

} // namespace dpapi
} // namespace win
} // namespace os
} // namespace mobius
