Rewrite SOCKS proxy parsing to allow for SOCKS5, also fix any remaining logs

SOCKS.cpp

@@ -5,6 +5,7 @@
 #include "ClientContext.h"
 #include "I2PEndian.h"
 #include <cstring>
+#include <cassert>
 
 namespace i2p
 {
@@ -15,17 +16,13 @@ namespace proxy
 
 	void SOCKS4AHandler::AsyncSockRead()
 	{
-		LogPrint("--- socks4a async sock read");
+		LogPrint(eLogDebug,"--- SOCKS async sock read");
 		if(m_sock) {
-			if (m_state == INITIAL) {
 			m_sock->async_receive(boost::asio::buffer(m_sock_buff, socks_buffer_size),
 						std::bind(&SOCKS4AHandler::HandleSockRecv, this,
 								std::placeholders::_1, std::placeholders::_2));
 		} else {
-				LogPrint("--- socks4a state?? ", m_state);
-			}
-		} else {
-			LogPrint("--- socks4a no socket for read");
+			LogPrint(eLogError,"--- SOCKS no socket for read");
 		}
 	}
 
@@ -37,7 +34,7 @@ namespace proxy
 
 	void SOCKS4AHandler::SocksFailed()
 	{
-		LogPrint("--- socks4a failed");
+		LogPrint(eLogWarning,"--- SOCKS failed");
 		//TODO: send the right response
 		boost::asio::async_write(*m_sock, boost::asio::buffer("\x00\x5b 12345"),
 					 std::bind(&SOCKS4AHandler::SentSocksFailed, this,
@@ -47,7 +44,7 @@ namespace proxy
 	void SOCKS4AHandler::CloseSock()
 	{
 		if (m_sock) {
-			LogPrint("--- socks4a close sock");
+			LogPrint(eLogDebug,"--- SOCKS close sock");
 			m_sock->close();
 			delete m_sock;
 			m_sock = nullptr;
@@ -57,7 +54,7 @@ namespace proxy
        void SOCKS4AHandler::CloseStream()
        {
                if (m_stream) {
-                       LogPrint("--- socks4a close stream");
+                       LogPrint(eLogDebug,"--- SOCKS close stream");
                        m_stream.reset ();
                }
        }
@@ -66,78 +63,147 @@ namespace proxy
 	const size_t socks_ident_size = 1024;
 	const size_t destb32_len = 52;
 
-	void SOCKS4AHandler::HandleSockRecv(const boost::system::error_code & ecode, std::size_t len)
+	std::size_t SOCKS4AHandler::HandleData(uint8_t *sock_buff, std::size_t len)
 	{
-		LogPrint("--- socks4a sock recv: ", len);
-		//TODO: we may not have received all the data :(
-		if(ecode) {
-			LogPrint(" --- sock recv got error: ", ecode);
+		assert(len); // This should always be called with a least a byte left to parse
+		switch (m_state) {
+			case GET_VERSION:
+				return HandleVersion(sock_buff);
+			case SOCKS4A:
+				return HandleSOCKS4A(sock_buff,len);
+			default:
+				LogPrint(eLogError,"--- SOCKS state?? ", m_state);
 				Terminate();
-			return;
+				return 0;
+		}
 	}
 
-		char hostbuff[socks_hostname_size];
-		char identbuff[socks_ident_size];
-		std::memset(hostbuff, 0, sizeof(hostbuff));
-		std::memset(identbuff, 0, sizeof(hostbuff));
-		std::string dest;
-
-		uint16_t port = 0;
-		uint32_t address = 0;
-		uint16_t idx1 = 0;
-		uint16_t idx2 = 0;
-
-		LogPrint(eLogDebug,"--- socks4a state initial ", len);
+	std::size_t SOCKS4AHandler::HandleVersion(uint8_t *sock_buff)
+	{
+		switch (*sock_buff) {
+			case 4:
+				m_state = SOCKS4A; // Switch to the 4a handler
+				m_pstate = GET4A_COMMAND; //Initialize the parser at the right position
+				return 1;
+			default:
+				LogPrint(eLogError,"--- SOCKS rejected invalid version", ((int)*sock_buff));
+				Terminate();
+				return 0;
+		}
+	}
 
-		// check valid request
-		if( m_sock_buff[0] != 4 || m_sock_buff[1] != 1 || m_sock_buff[len-1] ) {
-			LogPrint(eLogError,"--- socks4a rejected invalid");
+	std::size_t SOCKS4AHandler::HandleSOCKS4A(uint8_t *sock_buff, std::size_t len)
+	{
+		std::size_t rv = 0;
+		while (len > 0) {
+			rv++;
+			switch (m_pstate)
+			{
+				case GET4A_COMMAND:
+					if ( *sock_buff != 1 ) {
+						LogPrint(eLogError,"--- SOCKS4a unsupported command", ((int)*sock_buff));
 						SocksFailed();
-			return;
+						return 0;
+					}
+					m_pstate = GET4A_PORT1;
+					break;
+				case GET4A_PORT1:
+					m_port = ((uint16_t)*sock_buff) << 8;
+					m_pstate = GET4A_PORT2;
+					break;
+				case GET4A_PORT2:
+					m_port |= ((uint16_t)*sock_buff);
+					m_pstate = GET4A_IP1;
+					break;
+				case GET4A_IP1:
+					m_ip = ((uint32_t)*sock_buff) << 24;
+					m_pstate = GET4A_IP2;
+					break;
+				case GET4A_IP2:
+					m_ip |= ((uint32_t)*sock_buff) << 16;
+					m_pstate = GET4A_IP3;
+					break;
+				case GET4A_IP3:
+					m_ip |= ((uint32_t)*sock_buff) << 8;
+					m_pstate = GET4A_IP4;
+					break;
+				case GET4A_IP4:
+					m_ip |= ((uint32_t)*sock_buff);
+					m_pstate = GET4A_IDENT;
+					if( m_ip == 0 || m_ip > 255 ) {
+						LogPrint(eLogError,"--- SOCKS4a rejected because it's actually SOCKS4");
+						SocksFailed();
+						return 0;
+					}
+					break;
+				case GET4A_IDENT:
+					if (!*sock_buff)
+						m_pstate = GET4A_HOST;
+					break;
+				case GET4A_HOST:
+					if (!*sock_buff) {
+						m_pstate = DONE;
+						m_state = READY;
+						return rv;
+					}
+					if (m_destination.size() > HOST_NAME_MAX) {
+						LogPrint(eLogError,"--- SOCKS4a destination is too large ");
+						SocksFailed();
+						return 0;
+					}
+					m_destination.push_back(*sock_buff);
+					break;
+				default:
+					LogPrint(eLogError,"--- SOCKS4a parse state?? ", m_pstate);
+					Terminate();
+					return 0;
+			}
+			sock_buff++;
+			len--;
+		}
+		return rv;
 	}
 
-		// get port
-		port = bufbe16toh(m_sock_buff + 2);
+	void SOCKS4AHandler::HandleSockRecv(const boost::system::error_code & ecode, std::size_t len)
+	{
+		LogPrint(eLogDebug,"--- SOCKS sock recv: ", len);
+		if(ecode) {
+			LogPrint(eLogWarning," --- SOCKS sock recv got error: ", ecode);
+                        Terminate();
+			return;
+		}
 
-		// get address
-		address = bufbe32toh(m_sock_buff + 4);
+		std::size_t pos = 0;
+		while (pos != len && m_state != READY) {
+			assert(pos < len); //We are overflowing the buffer otherwise
+			std::size_t rv = HandleData(m_sock_buff + pos, len - pos);
+			if (!rv) return; //Something went wrong die misserably
+			pos += rv;
+		}
 
-		// check valid request
-		if( address == 0 || address > 255 ) {
-			LogPrint(eLogError,"--- socks4a rejected because it's actually socks4");
+		if (m_state == READY) {
+			LogPrint(eLogInfo,"--- SOCKS requested ", m_destination, ":" , m_port);
+			if (pos != len) {
+				LogPrint(eLogError,"--- SOCKS rejected because be can't handle extra data");
 				SocksFailed();
 				return ;
 			}
-
-		// read ident 
-		do {
-			LogPrint(eLogDebug,"--- socks4a ", (int) m_sock_buff[9+idx1]);
-			identbuff[idx1] = m_sock_buff[8+idx1];
-		} while( identbuff[idx1++] && idx1 < socks_ident_size );
-
-		LogPrint(eLogInfo,"--- socks4a ident ", identbuff);
-		// read hostname
-		do {
-			hostbuff[idx2] = m_sock_buff[8+idx1+idx2];
-		} while( hostbuff[idx2++] && idx2 < socks_hostname_size );
-
-		LogPrint(eLogInfo,"--- socks4a requested ", hostbuff, ":" , port);
-
-		dest = std::string(hostbuff);
-		if(dest.find(".i2p") == std::string::npos) {
-			LogPrint("--- socks4a invalid hostname: ", dest);
+			if(m_destination.find(".i2p") == std::string::npos) {
+				LogPrint(eLogError,"--- SOCKS invalid hostname: ", m_destination);
 				SocksFailed();
 				return;
 			}
 
+			// TODO: Pass port see m_port
 			m_parent->GetLocalDestination ()->CreateStream (
 					std::bind (&SOCKS4AHandler::HandleStreamRequestComplete,
-				this, std::placeholders::_1), dest);
+					this, std::placeholders::_1), m_destination);
+		}
 	}
 
 	void SOCKS4AHandler::ConnectionSuccess()
 	{
-		LogPrint(eLogInfo,"--- socks4a connection success");
+		LogPrint(eLogInfo,"--- SOCKS connection success");
 		//TODO: send the right response
 		boost::asio::async_write(*m_sock, boost::asio::buffer("\x00\x5a 12345"),
 					 std::bind(&SOCKS4AHandler::SentConnectionSuccess, this,
@@ -151,7 +217,7 @@ namespace proxy
 		}
 		else
 		{
-			LogPrint (eLogError,"--- socks4a Closing socket after sending failure because: ", ecode.message ());
+			LogPrint (eLogError,"--- SOCKS Closing socket after sending failure because: ", ecode.message ());
 			Terminate();
 		}
 	}
@@ -159,14 +225,14 @@ namespace proxy
 	void SOCKS4AHandler::SentConnectionSuccess(const boost::system::error_code & ecode)
 	{
 		if (!ecode) {
-			LogPrint (eLogInfo,"--- socks4a New I2PTunnel connection");
+			LogPrint (eLogInfo,"--- SOCKS New I2PTunnel connection");
 			auto connection = std::make_shared<i2p::client::I2PTunnelConnection>((i2p::client::I2PTunnel *)m_parent, m_sock, m_stream);
 			m_parent->AddConnection (connection);
 			connection->I2PConnect ();
 		}
 		else
 		{
-			LogPrint (eLogError,"--- socks4a Closing socket after sending success because: ", ecode.message ());
+			LogPrint (eLogError,"--- SOCKS Closing socket after sending success because: ", ecode.message ());
 			Terminate();
 		}
 	}
@@ -180,7 +246,7 @@ namespace proxy
 		}
 		else
 		{
-			LogPrint (eLogError,"--- socks4a Issue when creating the stream, check the previous warnings for more info.");
+			LogPrint (eLogError,"--- SOCKS Issue when creating the stream, check the previous warnings for more info.");
 			SocksFailed();
 		}
 	}
@@ -210,13 +276,13 @@ namespace proxy
 	{
 		if (!ecode)
 		{
-			LogPrint(eLogDebug,"--- socks4a accepted");
+			LogPrint(eLogDebug,"--- SOCKS accepted");
 			new SOCKS4AHandler(this, socket);
 			Accept();
 		}
 		else
 		{
-			LogPrint (eLogError,"--- socks4a Closing socket on accept because: ", ecode.message ());
+			LogPrint (eLogError,"--- SOCKS Closing socket on accept because: ", ecode.message ());
 			delete socket;
 		}
 	}

SOCKS.h

@@ -1,6 +1,7 @@
 #ifndef SOCKS4A_H__
 #define SOCKS4A_H__
 
+#include <climits>
 #include <memory>
 #include <boost/asio.hpp>
 #include "Identity.h"
@@ -19,12 +20,27 @@ namespace proxy
 
 		private:
 			enum state {
-                    INITIAL,
-                    OKAY,
-                    END
+				GET_VERSION,
+				SOCKS4A,
+				READY
+			};
+			enum parseState {
+				GET4A_COMMAND,
+				GET4A_PORT1,
+				GET4A_PORT2,
+				GET4A_IP1,
+				GET4A_IP2,
+				GET4A_IP3,
+				GET4A_IP4,
+				GET4A_IDENT,
+				GET4A_HOST,
+				DONE
 			};
 
 			void GotClientRequest(boost::system::error_code & ecode, std::string & host, uint16_t port);
+			std::size_t HandleData(uint8_t *sock_buff, std::size_t len);
+			std::size_t HandleVersion(uint8_t *sock_buff);
+			std::size_t HandleSOCKS4A(uint8_t *sock_buff, std::size_t len);
 			void HandleSockRecv(const boost::system::error_code & ecode, std::size_t bytes_transfered);
 			void Terminate();
 			void CloseSock();
@@ -42,15 +58,19 @@ namespace proxy
 			boost::asio::ip::tcp::socket * m_sock;
 			std::shared_ptr<i2p::stream::Stream> m_stream;
 			state m_state;
+			parseState m_pstate;
+			uint8_t m_command;
+			uint16_t m_port;
+			uint32_t m_ip;
+			std::string m_destination;
 		
             
 		public:
 			SOCKS4AHandler(SOCKS4AServer * parent, boost::asio::ip::tcp::socket * sock) : 
-				m_parent(parent), m_sock(sock), m_stream(nullptr), m_state(INITIAL)
-				{ AsyncSockRead(); }
+				m_parent(parent), m_sock(sock), m_stream(nullptr), m_state(GET_VERSION)
+				{ AsyncSockRead(); m_destination.reserve(HOST_NAME_MAX+1); }
 
 			~SOCKS4AHandler() { CloseSock(); CloseStream(); }
-			bool isComplete() { return m_state == END; }
 	};
 
 	class SOCKS4AServer: public i2p::client::I2PTunnel