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/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/*
* Copyright (c) 2013-2017 Regents of the University of California.
*
* This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
*
* ndn-cxx library is free software: you can redistribute it and/or modify it under the
* terms of the GNU Lesser General Public License as published by the Free Software
* Foundation, either version 3 of the License, or (at your option) any later version.
*
* ndn-cxx library 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 Lesser General Public License for more details.
*
* You should have received copies of the GNU General Public License and GNU Lesser
* General Public License along with ndn-cxx, e.g., in COPYING.md file. If not, see
* <http://www.gnu.org/licenses/>.
*
* See AUTHORS.md for complete list of ndn-cxx authors and contributors.
*/
#include "hex-decode.hpp"
namespace ndn {
namespace security {
namespace transform {
// hex decoding pad
static const int8_t C2H[] = {
// 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // 0-15
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // 16-31
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // 32-47
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1, // 48-63
-1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, // 64-79
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // 80-95
-1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, // 96-111
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // 112-127
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // 128-143
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // 144-159
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // 160-175
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // 176-191
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // 192-207
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // 208-223
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // 224-239
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // 240-255
};
static_assert(std::extent<decltype(C2H)>::value == 256, "");
HexDecode::HexDecode()
: m_hasOddByte(false)
, m_oddByte(0)
{
}
size_t
HexDecode::convert(const uint8_t* hex, size_t hexLen)
{
if (hexLen == 0)
return 0;
setOutputBuffer(toBytes(hex, hexLen));
size_t totalDecodedLen = hexLen + (m_hasOddByte ? 1 : 0);
if (totalDecodedLen % 2 == 1) {
m_oddByte = hex[hexLen - 1];
m_hasOddByte = true;
}
else
m_hasOddByte = false;
return hexLen;
}
void
HexDecode::finalize()
{
if (m_hasOddByte)
BOOST_THROW_EXCEPTION(Error(getIndex(), "Incomplete input"));
}
unique_ptr<Transform::OBuffer>
HexDecode::toBytes(const uint8_t* hex, size_t hexLen)
{
size_t bufferSize = (hexLen + (m_hasOddByte ? 1 : 0)) >> 1;
auto buffer = make_unique<OBuffer>(bufferSize);
auto it = buffer->begin();
if (m_hasOddByte) {
if (C2H[hex[0]] < 0 || C2H[m_oddByte] < 0)
BOOST_THROW_EXCEPTION(Error(getIndex(), "Wrong input byte"));
*it = (C2H[m_oddByte] << 4) + C2H[hex[0]];
++it;
hex += 1;
hexLen -= 1;
}
while (hexLen >= 2) {
if (C2H[hex[0]] < 0 || C2H[hex[1]] < 0)
BOOST_THROW_EXCEPTION(Error(getIndex(), "Wrong input byte"));
*it = (C2H[hex[0]] << 4) + C2H[hex[1]];
++it;
hex += 2;
hexLen -= 2;
}
return buffer;
}
unique_ptr<Transform>
hexDecode()
{
return make_unique<HexDecode>();
}
} // namespace transform
} // namespace security
} // namespace ndn