i2pd/SOCKS.h

160 lines
4.9 KiB
C++

#ifndef SOCKS_H__
#define SOCKS_H__
#include <memory>
#include <vector>
#include <boost/asio.hpp>
#include "Identity.h"
#include "Streaming.h"
#include "I2PTunnel.h"
namespace i2p
{
namespace proxy
{
const size_t socks_buffer_size = 8192;
const size_t max_socks_hostname_size = 255; // Limit for socks5 and bad idea to traverse
class SOCKSServer;
class SOCKSHandler {
private:
enum state {
GET_VERSION, // Get SOCKS version
SOCKS5_AUTHNEGO, //Authentication negotiation
SOCKS5_AUTH, //Authentication
SOCKS_REQUEST, //Request
READY // Ready to connect
};
enum parseState {
GET_COMMAND,
GET_PORT,
GET_IPV4,
GET4_IDENT,
GET4A_HOST,
GET5_AUTHNUM,
GET5_AUTH,
GET5_REQUESTV,
GET5_GETRSV,
GET5_GETADDRTYPE,
GET5_IPV6,
GET5_HOST_SIZE,
GET5_HOST,
DONE
};
enum authMethods {
AUTH_NONE = 0, //No authentication, skip to next step
AUTH_GSSAPI = 1, //GSSAPI authentication
AUTH_USERPASSWD = 2, //Username and password
AUTH_UNACCEPTABLE = 0xff //No acceptable method found
};
enum addrTypes {
ADDR_IPV4 = 1, //IPv4 address (4 octets)
ADDR_DNS = 3, // DNS name (up to 255 octets)
ADDR_IPV6 = 4 //IPV6 address (16 octets)
};
enum errTypes {
SOCKS5_OK = 0, // No error for SOCKS5
SOCKS5_GEN_FAIL = 1, // General server failure
SOCKS5_RULE_DENIED = 2, // Connection disallowed by ruleset
SOCKS5_NET_UNREACH = 3, // Network unreachable
SOCKS5_HOST_UNREACH = 4, // Host unreachable
SOCKS5_CONN_REFUSED = 5, // Connection refused by the peer
SOCKS5_TTL_EXPIRED = 6, // TTL Expired
SOCKS5_CMD_UNSUP = 7, // Command unsuported
SOCKS5_ADDR_UNSUP = 8, // Address type unsuported
SOCKS4_OK = 90, // No error for SOCKS4
SOCKS4_FAIL = 91, // Failed establishing connecting or not allowed
SOCKS4_IDENTD_MISSING = 92, // Couldn't connect to the identd server
SOCKS4_IDENTD_DIFFER = 93 // The ID reported by the application and by identd differ
};
enum cmdTypes {
CMD_CONNECT = 1, // TCP Connect
CMD_BIND = 2, // TCP Bind
CMD_UDP = 3 // UDP associate
};
enum socksVersions {
SOCKS4 = 4, // SOCKS4
SOCKS5 = 5 // SOCKS5
};
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 HandleSOCKS5AuthNego(uint8_t *sock_buff, std::size_t len);
std::size_t HandleSOCKSRequest(uint8_t *sock_buff, std::size_t len);
bool ValidateSOCKSRequest();
void HandleSockRecv(const boost::system::error_code & ecode, std::size_t bytes_transfered);
void Terminate();
void CloseSock();
void CloseStream();
void AsyncSockRead();
void Socks5AuthNegoFailed();
void Socks5ChooseAuth();
void SocksRequestFailed();
void SocksRequestSuccess();
void SentSocksFailed(const boost::system::error_code & ecode);
//HACK: we need to pass the shared_ptr to ensure the buffer will live enough
void SentSocksResponse(const boost::system::error_code & ecode, std::shared_ptr<std::vector<uint8_t>> response);
void HandleStreamRequestComplete (std::shared_ptr<i2p::stream::Stream> stream);
uint8_t m_sock_buff[socks_buffer_size];
SOCKSServer * m_parent;
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;
uint8_t m_ipv6[16];
std::string m_destination;
uint8_t m_authleft; //Authentication methods left
//TODO: this will probably be more elegant as enums
authMethods m_authchosen; //Authentication chosen
addrTypes m_addrtype; //Address type chosen
uint8_t m_addrleft; //Octets of DNS address left
errTypes m_error; //Error cause
socksVersions m_socksv; //Socks version
cmdTypes m_cmd; // Command requested
bool m_need_more; //The parser still needs to receive more data
public:
SOCKSHandler(SOCKSServer * parent, boost::asio::ip::tcp::socket * sock) :
m_parent(parent), m_sock(sock), m_stream(nullptr), m_state(GET_VERSION),
m_authchosen(AUTH_UNACCEPTABLE), m_addrtype(ADDR_IPV4), m_error(SOCKS5_GEN_FAIL)
{ AsyncSockRead(); m_destination.reserve(max_socks_hostname_size+1); }
~SOCKSHandler() { CloseSock(); CloseStream(); }
};
class SOCKSServer: public i2p::client::I2PTunnel
{
public:
SOCKSServer(int port) : I2PTunnel(nullptr),
m_Acceptor (GetService (), boost::asio::ip::tcp::endpoint (boost::asio::ip::tcp::v4(), port)),
m_Timer (GetService ()) {};
~SOCKSServer() { Stop(); }
void Start ();
void Stop ();
private:
void Accept();
void HandleAccept(const boost::system::error_code& ecode, boost::asio::ip::tcp::socket * socket);
private:
boost::asio::ip::tcp::acceptor m_Acceptor;
boost::asio::deadline_timer m_Timer;
};
typedef SOCKSServer SOCKSProxy;
}
}
#endif