rlpx frame reader fixes. rename writer::drain to mux.

libp2p/RLPXFrameWriter.cpp

@@ -32,7 +32,7 @@ void RLPXFrameWriter::enque(unsigned _packetType, RLPStream& _payload, PacketPri
 		qs.q.push_back(move(RLPXPacket(m_protocolType, _packetType, _payload)));
 }
 
-size_t RLPXFrameWriter::drain(RLPXFrameCoder& _coder, unsigned _size, vector<bytes>& o_toWrite)
+size_t RLPXFrameWriter::mux(RLPXFrameCoder& _coder, unsigned _size, vector<bytes>& o_toWrite)
 {
 	static const size_t c_blockSize = h128::size;
 	static const size_t c_overhead = c_blockSize * 3; // header + headerMac + frameMAC

libp2p/RLPXFrameWriter.h

@@ -33,61 +33,71 @@ namespace dev
 namespace p2p
 {
 
+/**
+ * RLPFrameReader
+ * Reads and assembles RLPX frame byte buffers into RLPX packets. Additionally
+ * buffers incomplete packets which are pieced into multiple frames (has sequence).
+ * @todo drop frame and reset incomplete if
+ * @todo percolate sequenceid to p2p protocol
+ * @todo informative exception
+ */
 class RLPXFrameReader
 {
 	RLPXFrameReader(uint16_t _protocolType): m_protocolType(_protocolType) {}
 	
-	std::vector<RLPXPacket> assemble(bytes& _in)
+	/// Processes a single frame returning complete packets.
+	std::vector<RLPXPacket> demux(bytes& _frame, bool _sequence = false, uint16_t _seq = 0, uint32_t _totalSize = 0)
 	{
-		bytesConstRef buffer(&_in);
 		std::vector<RLPXPacket> ret;
-		if (!_in.size())
+		if (!_frame.size() || _frame.size() > _totalSize)
 			return ret;
-		
+
+		if (_sequence && m_incomplete.count(_seq))
+		{
+			uint32_t& remaining = m_incomplete.at(_seq).second;
+			if (!_totalSize && _frame.size() <= remaining)
+			{
+				RLPXPacket& p = m_incomplete.at(_seq).first;
+				if (_frame.size() > remaining)
+					return ret;
+				else if(p.streamIn(&_frame))
+				{
+					ret.push_back(std::move(p));
+					m_incomplete.erase(_seq);
+				}
+				else
+					remaining -= _frame.size();
+				return ret;
+			}
+			else
+				m_incomplete.erase(_seq);
+		}
+
+		bytesConstRef buffer(&_frame);
 		while (!buffer.empty())
 		{
 			auto type = RLPXPacket::nextRLP(buffer);
+			if (type.empty())
+				break;
 			buffer = buffer.cropped(type.size());
-			auto packet = RLPXPacket::nextRLP(buffer);
+			// consume entire buffer if packet has sequence
+			auto packet = _sequence ? buffer : RLPXPacket::nextRLP(buffer);
 			buffer = buffer.cropped(packet.size());
 			RLPXPacket p(m_protocolType, type);
-			p.streamIn(packet);
-			ret.push_back(std::move(p));
-		}
-		return ret;
-	}
-	
-	std::vector<RLPXPacket> assemble(bytes& _in, uint16_t _seq, uint32_t _totalSize)
-	{
-		// TODO: cleanup sequencing api (throw exception(s) when bad things happen)
-		
-		bytesConstRef buffer(&_in);
-		if (!m_incomplete.count(_seq) && _totalSize > 0)
-		{
-			// new packet
-			RLPXPacket p(m_protocolType, buffer);
-			if (p.isValid())
-				return std::vector<RLPXPacket>{std::move(p)};
-			m_incomplete[_seq] = std::move(p);
-		}
-		else
-		{
-			RLPXPacket& p = m_incomplete[_seq];
-			p.streamIn(buffer);
+			if (!packet.empty())
+				p.streamIn(packet);
+			
 			if (p.isValid())
-			{
-				std::vector<RLPXPacket> ret{std::move(p)};
-				m_incomplete.erase(_seq);
-				return ret;
-			}
+				ret.push_back(std::move(p));
+			else if (_sequence)
+				m_incomplete.insert(std::make_pair(_seq, std::make_pair(std::move(p), _totalSize - _frame.size())));
 		}
-
-		return std::vector<RLPXPacket>();
+		return ret;
 	}
 	
 protected:
 	uint16_t m_protocolType;
-	std::map<uint16_t, RLPXPacket> m_incomplete;	///< Incomplete packets which span multiple frames.
+	std::map<uint16_t, std::pair<RLPXPacket, uint32_t>> m_incomplete;	///< Incomplete packets and bytes remaining.
 };
 
 class RLPXFrameWriter
@@ -112,11 +122,11 @@ public:
 	
 	size_t size() const { size_t l; size_t h; DEV_GUARDED(m_q.first.x) h = m_q.first.q.size(); DEV_GUARDED(m_q.second.x) l = m_q.second.q.size(); return l + h; }
 	
-	/// Contents of _payload will be moved. Thread-safe.
+	/// Contents of _payload will be moved. Adds packet to queue, to be muxed into frames by mux when network buffer is ready for writing. Thread-safe.
 	void enque(unsigned _packetType, RLPStream& _payload, PacketPriority _priority = PriorityLow);
 	
 	/// Returns number of packets framed and outputs frames to o_bytes. Not thread-safe.
-	size_t drain(RLPXFrameCoder& _coder, unsigned _size, std::vector<bytes>& o_toWrite);
+	size_t mux(RLPXFrameCoder& _coder, unsigned _size, std::vector<bytes>& o_toWrite);
 	
 private:
 	uint16_t const m_protocolType;			// Protocol Type

libp2p/RLPXPacket.h

@@ -40,18 +40,22 @@ public:
 	static bytesConstRef nextRLP(bytesConstRef _b) { try { RLP r(_b, RLP::AllowNonCanon); auto s = r.actualSize(); if (s >= _b.size()) return _b.cropped(s); } catch(...) {} return bytesConstRef(); }
 	
 	/// Construct complete packet. RLPStream data is moved.
-	RLPXPacket(unsigned _capId, unsigned _type, RLPStream&& _rlps): m_cap(_capId), m_type(_type), m_data(std::move(_rlps.out())) { if (!_type && !m_data.size()) BOOST_THROW_EXCEPTION(RLPXNullPacket()); }
+	RLPXPacket(unsigned _capId, unsigned _type, RLPStream& _rlps): m_cap(_capId), m_type(_type), m_data(std::move(_rlps.out())) { if (!_type && !m_data.size()) BOOST_THROW_EXCEPTION(RLPXNullPacket()); }
 
 	/// Construct packet with type and initial bytes; type is determined by RLP of 1st byte and packet may be incomplete.
 	RLPXPacket(unsigned _capId, bytesConstRef _in): m_cap(_capId), m_type(getType(_in)) { assert(_in.size()); if (_in.size() > 1) { m_data.resize(_in.size() - 1); _in.cropped(1).copyTo(&m_data); } }
 	
+	RLPXPacket(RLPXPacket const& _p): m_cap(_p.m_cap), m_type(_p.m_type), m_data(_p.m_data) {}
+	
+	RLPXPacket(RLPXPacket&& _p): m_cap(_p.m_cap), m_type(_p.m_type), m_data(std::move(_p.m_data)) {}
+	
 	unsigned type() const { return m_type; }
 	bytes const& data() const { return m_data; }
-	size_t size() const { return m_data.size(); }
-	
-	bool streamIn(bytesConstRef _in) { auto offset = m_data.size(); m_data.resize(offset + _in.size()); _in.copyTo(byestConstRef(m_data).cropped(offset)); return isValid(); }
+	size_t size() const { try { return RLP(m_data, RLP::LaisezFaire).actualSize(); } catch(...) { return 0; } }
+
+	bool streamIn(bytesConstRef _in) { auto offset = m_data.size(); m_data.resize(offset + _in.size()); _in.copyTo(bytesRef(&m_data).cropped(offset)); return isValid(); }
 	
-	bool isValid() { if (m_type > 0x7f) return false; try { if (RLP(m_data).actualSize() == m_data.size()) return true; } catch (...) {} return false; }
+	bool isValid() { if (m_type > 0x7f) return false; try { return RLP(m_data).actualSize() == m_data.size(); } catch (...) {} return false; }
 	
 
 protected:
@@ -59,6 +63,7 @@ protected:
 	
 	unsigned m_cap;
 	unsigned m_type;
+	uint16_t m_sequence = 0;
 	bytes m_data;
 };
 

libp2p/RLPXSocketIO.cpp

@@ -74,7 +74,7 @@ void RLPXSocketIO::doWrite()
 	size_t protFrameSize = capacity / active;
 	if (protFrameSize >= MinFrameSize)
 		for (auto& w: m_writers)
-			dequed += w.drain(m_coder, protFrameSize, m_toSend);
+			dequed += w.mux(m_coder, protFrameSize, m_toSend);
 
 	if (dequed)
 		write(dequed);

test/libp2p/rlpx.cpp

@@ -484,13 +484,13 @@ BOOST_AUTO_TEST_CASE(readerWriter)
 	vector<bytes> out;
 	for (unsigned i = 1; i < drains; i++)
 	{
-		auto n = w.drain(coder, RLPXFrameWriter::MinFrameDequeLength, out);
+		auto n = w.mux(coder, RLPXFrameWriter::MinFrameDequeLength, out);
 		BOOST_REQUIRE_EQUAL(0, n);
 		BOOST_REQUIRE_EQUAL(out.size(), i);
 	}
-	BOOST_REQUIRE_EQUAL(1, w.drain(coder, RLPXFrameWriter::MinFrameDequeLength, out));
+	BOOST_REQUIRE_EQUAL(1, w.mux(coder, RLPXFrameWriter::MinFrameDequeLength, out));
 	BOOST_REQUIRE_EQUAL(out.size(), drains);
-	BOOST_REQUIRE_EQUAL(0, w.drain(coder, RLPXFrameWriter::MinFrameDequeLength, out));
+	BOOST_REQUIRE_EQUAL(0, w.mux(coder, RLPXFrameWriter::MinFrameDequeLength, out));
 	BOOST_REQUIRE_EQUAL(out.size(), drains);
 	
 	// we should now have a bunch of ciphertext in out