| /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */ |
| /** |
| * Copyright (c) 2013-2014 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. |
| * |
| * @author Alexander Afanasyev <http://lasr.cs.ucla.edu/afanasyev/index.html> |
| */ |
| |
| #include "common.hpp" |
| |
| #include "block.hpp" |
| #include "block-helpers.hpp" |
| |
| #include "tlv.hpp" |
| #include "encoding-buffer.hpp" |
| #include "buffer-stream.hpp" |
| |
| #include <boost/lexical_cast.hpp> |
| #include <boost/asio/buffer.hpp> |
| |
| namespace ndn { |
| |
| const size_t MAX_SIZE_OF_BLOCK_FROM_STREAM = 8800; |
| |
| Block::Block() |
| : m_type(std::numeric_limits<uint32_t>::max()) |
| { |
| } |
| |
| Block::Block(const EncodingBuffer& buffer) |
| : m_buffer(buffer.m_buffer) |
| , m_begin(buffer.begin()) |
| , m_end(buffer.end()) |
| , m_size(m_end - m_begin) |
| { |
| m_value_begin = m_begin; |
| m_value_end = m_end; |
| |
| m_type = Tlv::readType(m_value_begin, m_value_end); |
| uint64_t length = Tlv::readVarNumber(m_value_begin, m_value_end); |
| if (length != static_cast<uint64_t>(m_value_end - m_value_begin)) |
| { |
| throw Tlv::Error("TLV length doesn't match buffer length"); |
| } |
| } |
| |
| Block::Block(const ConstBufferPtr& wire, |
| uint32_t type, |
| const Buffer::const_iterator& begin, const Buffer::const_iterator& end, |
| const Buffer::const_iterator& valueBegin, const Buffer::const_iterator& valueEnd) |
| : m_buffer(wire) |
| , m_type(type) |
| , m_begin(begin) |
| , m_end(end) |
| , m_size(m_end - m_begin) |
| , m_value_begin(valueBegin) |
| , m_value_end(valueEnd) |
| { |
| } |
| |
| Block::Block(const ConstBufferPtr& buffer) |
| : m_buffer(buffer) |
| , m_begin(m_buffer->begin()) |
| , m_end(m_buffer->end()) |
| , m_size(m_end - m_begin) |
| { |
| m_value_begin = m_begin; |
| m_value_end = m_end; |
| |
| m_type = Tlv::readType(m_value_begin, m_value_end); |
| |
| uint64_t length = Tlv::readVarNumber(m_value_begin, m_value_end); |
| if (length != static_cast<uint64_t>(m_value_end - m_value_begin)) |
| { |
| throw Tlv::Error("TLV length doesn't match buffer length"); |
| } |
| } |
| |
| Block::Block(const ConstBufferPtr& buffer, |
| const Buffer::const_iterator& begin, const Buffer::const_iterator& end, |
| bool verifyLength/* = true*/) |
| : m_buffer(buffer) |
| , m_begin(begin) |
| , m_end(end) |
| , m_size(m_end - m_begin) |
| { |
| m_value_begin = m_begin; |
| m_value_end = m_end; |
| |
| m_type = Tlv::readType(m_value_begin, m_value_end); |
| uint64_t length = Tlv::readVarNumber(m_value_begin, m_value_end); |
| if (verifyLength) |
| { |
| if (length != static_cast<uint64_t>(m_value_end - m_value_begin)) |
| { |
| throw Tlv::Error("TLV length doesn't match buffer length"); |
| } |
| } |
| } |
| |
| |
| Block::Block(const uint8_t* buffer, size_t maxlength) |
| { |
| const uint8_t* tmp_begin = buffer; |
| const uint8_t* tmp_end = buffer + maxlength; |
| |
| m_type = Tlv::readType(tmp_begin, tmp_end); |
| uint64_t length = Tlv::readVarNumber(tmp_begin, tmp_end); |
| |
| if (length > static_cast<uint64_t>(tmp_end - tmp_begin)) |
| { |
| throw Tlv::Error("Not enough data in the buffer to fully parse TLV"); |
| } |
| |
| m_buffer = make_shared<Buffer>(buffer, (tmp_begin - buffer) + length); |
| |
| m_begin = m_buffer->begin(); |
| m_end = m_buffer->end(); |
| m_size = m_end - m_begin; |
| |
| m_value_begin = m_buffer->begin() + (tmp_begin - buffer); |
| m_value_end = m_buffer->end(); |
| } |
| |
| Block::Block(const void* bufferX, size_t maxlength) |
| { |
| const uint8_t* buffer = reinterpret_cast<const uint8_t*>(bufferX); |
| |
| const uint8_t* tmp_begin = buffer; |
| const uint8_t* tmp_end = buffer + maxlength; |
| |
| m_type = Tlv::readType(tmp_begin, tmp_end); |
| uint64_t length = Tlv::readVarNumber(tmp_begin, tmp_end); |
| |
| if (length > static_cast<uint64_t>(tmp_end - tmp_begin)) |
| { |
| throw Tlv::Error("Not enough data in the buffer to fully parse TLV"); |
| } |
| |
| m_buffer = make_shared<Buffer>(buffer, (tmp_begin - buffer) + length); |
| |
| m_begin = m_buffer->begin(); |
| m_end = m_buffer->end(); |
| m_size = m_end - m_begin; |
| |
| m_value_begin = m_buffer->begin() + (tmp_begin - buffer); |
| m_value_end = m_buffer->end(); |
| } |
| |
| Block::Block(uint32_t type) |
| : m_type(type) |
| { |
| } |
| |
| Block::Block(uint32_t type, const ConstBufferPtr& value) |
| : m_buffer(value) |
| , m_type(type) |
| , m_begin(m_buffer->end()) |
| , m_end(m_buffer->end()) |
| , m_value_begin(m_buffer->begin()) |
| , m_value_end(m_buffer->end()) |
| { |
| m_size = Tlv::sizeOfVarNumber(m_type) + Tlv::sizeOfVarNumber(value_size()) + value_size(); |
| } |
| |
| Block::Block(uint32_t type, const Block& value) |
| : m_buffer(value.m_buffer) |
| , m_type(type) |
| , m_begin(m_buffer->end()) |
| , m_end(m_buffer->end()) |
| , m_value_begin(value.begin()) |
| , m_value_end(value.end()) |
| { |
| m_size = Tlv::sizeOfVarNumber(m_type) + Tlv::sizeOfVarNumber(value_size()) + value_size(); |
| } |
| |
| Block |
| Block::fromStream(std::istream& is) |
| { |
| std::istream_iterator<uint8_t> tmp_begin(is); |
| std::istream_iterator<uint8_t> tmp_end; |
| |
| uint32_t type = Tlv::readType(tmp_begin, tmp_end); |
| uint64_t length = Tlv::readVarNumber(tmp_begin, tmp_end); |
| |
| if (length > MAX_SIZE_OF_BLOCK_FROM_STREAM) |
| throw Tlv::Error("Length of block from stream is too large"); |
| |
| // We may still have some problem here, if some exception happens, |
| // we may completely lose all the bytes extracted from the stream. |
| |
| char buf[MAX_SIZE_OF_BLOCK_FROM_STREAM]; |
| buf[0] = *tmp_begin; |
| is.read(buf+1, length-1); |
| |
| if (length != static_cast<uint64_t>(is.gcount()) + 1) { |
| throw Tlv::Error("Not enough data in the buffer to fully parse TLV"); |
| } |
| |
| return dataBlock(type, buf, length); |
| } |
| |
| bool |
| Block::fromBuffer(const ConstBufferPtr& wire, size_t offset, Block& block) |
| { |
| Buffer::const_iterator tempBegin = wire->begin() + offset; |
| |
| uint32_t type; |
| bool isOk = Tlv::readType(tempBegin, wire->end(), type); |
| if (!isOk) |
| return false; |
| |
| uint64_t length; |
| isOk = Tlv::readVarNumber(tempBegin, wire->end(), length); |
| if (!isOk) |
| return false; |
| |
| if (length > static_cast<uint64_t>(wire->end() - tempBegin)) |
| { |
| return false; |
| } |
| |
| block = Block(wire, type, |
| wire->begin() + offset, tempBegin + length, |
| tempBegin, tempBegin + length); |
| |
| return true; |
| } |
| |
| bool |
| Block::fromBuffer(const uint8_t* buffer, size_t maxSize, Block& block) |
| { |
| const uint8_t* tempBegin = buffer; |
| const uint8_t* tempEnd = buffer + maxSize; |
| |
| uint32_t type = 0; |
| bool isOk = Tlv::readType(tempBegin, tempEnd, type); |
| if (!isOk) |
| return false; |
| |
| uint64_t length; |
| isOk = Tlv::readVarNumber(tempBegin, tempEnd, length); |
| if (!isOk) |
| return false; |
| |
| if (length > static_cast<uint64_t>(tempEnd - tempBegin)) |
| { |
| return false; |
| } |
| |
| BufferPtr sharedBuffer = make_shared<Buffer>(buffer, tempBegin + length); |
| block = Block(sharedBuffer, type, |
| sharedBuffer->begin(), sharedBuffer->end(), |
| sharedBuffer->begin() + (tempBegin - buffer), sharedBuffer->end()); |
| |
| return true; |
| } |
| |
| void |
| Block::parse() const |
| { |
| if (!m_subBlocks.empty() || value_size() == 0) |
| return; |
| |
| Buffer::const_iterator begin = value_begin(); |
| Buffer::const_iterator end = value_end(); |
| |
| while (begin != end) |
| { |
| Buffer::const_iterator element_begin = begin; |
| |
| uint32_t type = Tlv::readType(begin, end); |
| uint64_t length = Tlv::readVarNumber(begin, end); |
| |
| if (length > static_cast<uint64_t>(end - begin)) |
| { |
| m_subBlocks.clear(); |
| throw Tlv::Error("TLV length exceeds buffer length"); |
| } |
| Buffer::const_iterator element_end = begin + length; |
| |
| m_subBlocks.push_back(Block(m_buffer, |
| type, |
| element_begin, element_end, |
| begin, element_end)); |
| |
| begin = element_end; |
| // don't do recursive parsing, just the top level |
| } |
| } |
| |
| void |
| Block::encode() |
| { |
| if (hasWire()) |
| return; |
| |
| OBufferStream os; |
| Tlv::writeVarNumber(os, type()); |
| |
| if (hasValue()) |
| { |
| Tlv::writeVarNumber(os, value_size()); |
| os.write(reinterpret_cast<const char*>(value()), value_size()); |
| } |
| else if (m_subBlocks.size() == 0) |
| { |
| Tlv::writeVarNumber(os, 0); |
| } |
| else |
| { |
| size_t valueSize = 0; |
| for (element_const_iterator i = m_subBlocks.begin(); i != m_subBlocks.end(); ++i) { |
| valueSize += i->size(); |
| } |
| |
| Tlv::writeVarNumber(os, valueSize); |
| |
| for (element_const_iterator i = m_subBlocks.begin(); i != m_subBlocks.end(); ++i) { |
| if (i->hasWire()) |
| os.write(reinterpret_cast<const char*>(i->wire()), i->size()); |
| else if (i->hasValue()) { |
| Tlv::writeVarNumber(os, i->type()); |
| Tlv::writeVarNumber(os, i->value_size()); |
| os.write(reinterpret_cast<const char*>(i->value()), i->value_size()); |
| } |
| else |
| throw Error("Underlying value buffer is empty"); |
| } |
| } |
| |
| // now assign correct block |
| |
| m_buffer = os.buf(); |
| m_begin = m_buffer->begin(); |
| m_end = m_buffer->end(); |
| m_size = m_end - m_begin; |
| |
| m_value_begin = m_buffer->begin(); |
| m_value_end = m_buffer->end(); |
| |
| Tlv::readType(m_value_begin, m_value_end); |
| Tlv::readVarNumber(m_value_begin, m_value_end); |
| } |
| |
| Block |
| Block::blockFromValue() const |
| { |
| if (value_size() == 0) |
| throw Error("Underlying value buffer is empty"); |
| |
| Buffer::const_iterator begin = value_begin(), |
| end = value_end(); |
| |
| Buffer::const_iterator element_begin = begin; |
| |
| uint32_t type = Tlv::readType(begin, end); |
| uint64_t length = Tlv::readVarNumber(begin, end); |
| |
| if (length != static_cast<uint64_t>(end - begin)) |
| throw Tlv::Error("TLV length mismatches buffer length"); |
| |
| return Block(m_buffer, |
| type, |
| element_begin, end, |
| begin, end); |
| } |
| |
| const Block& |
| Block::get(uint32_t type) const |
| { |
| for (element_const_iterator i = m_subBlocks.begin(); |
| i != m_subBlocks.end(); |
| i++) |
| { |
| if (i->type() == type) |
| { |
| return *i; |
| } |
| } |
| |
| throw Error("(Block::get) Requested a non-existed type [" + |
| boost::lexical_cast<std::string>(type) + "] from Block"); |
| } |
| |
| Block::operator boost::asio::const_buffer() const |
| { |
| return boost::asio::const_buffer(wire(), size()); |
| } |
| |
| |
| } // namespace ndn |