mirror of https://github.com/PurpleI2P/i2pd.git
I2P: End-to-End encrypted and anonymous Internet
https://i2pd.website/
830 lines
25 KiB
830 lines
25 KiB
/* |
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* Copyright (c) 2013-2024, The PurpleI2P Project |
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* |
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* This file is part of Purple i2pd project and licensed under BSD3 |
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* |
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* See full license text in LICENSE file at top of project tree |
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*/ |
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#include <cstring> |
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#include <cassert> |
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#include <string> |
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#include <atomic> |
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#include "SOCKS.h" |
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#include "Identity.h" |
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#include "Streaming.h" |
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#include "Destination.h" |
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#include "ClientContext.h" |
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#include "I2PEndian.h" |
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#include "I2PTunnel.h" |
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#include "I2PService.h" |
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#include "util.h" |
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#include "Socks5.h" |
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namespace i2p |
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{ |
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namespace proxy |
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{ |
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static const size_t socks_buffer_size = 8192; |
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static const size_t max_socks_hostname_size = 255; // Limit for socks5 and bad idea to traverse |
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struct SOCKSDnsAddress |
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{ |
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uint8_t size; |
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char value[max_socks_hostname_size]; |
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void FromString (const std::string& str) |
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{ |
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size = str.length(); |
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if (str.length() > max_socks_hostname_size) size = max_socks_hostname_size; |
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memcpy(value,str.c_str(),size); |
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} |
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std::string ToString() { return std::string(value, size); } |
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void push_back (char c) { value[size++] = c; } |
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}; |
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class SOCKSServer; |
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class SOCKSHandler: public i2p::client::I2PServiceHandler, public std::enable_shared_from_this<SOCKSHandler> |
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{ |
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private: |
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enum state |
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{ |
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GET_SOCKSV, |
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GET_COMMAND, |
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GET_PORT, |
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GET_IPV4, |
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GET4_IDENT, |
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GET4A_HOST, |
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GET5_AUTHNUM, |
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GET5_AUTH, |
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GET5_REQUESTV, |
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GET5_GETRSV, |
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GET5_GETADDRTYPE, |
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GET5_IPV6, |
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GET5_HOST_SIZE, |
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GET5_HOST, |
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GET5_USERPASSWD, |
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GET5_USER_SIZE, |
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GET5_USER, |
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GET5_PASSWD_SIZE, |
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GET5_PASSWD, |
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READY, |
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UPSTREAM_RESOLVE, |
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UPSTREAM_CONNECT, |
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UPSTREAM_HANDSHAKE |
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}; |
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enum authMethods |
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{ |
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AUTH_NONE = 0, //No authentication, skip to next step |
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AUTH_GSSAPI = 1, //GSSAPI authentication |
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AUTH_USERPASSWD = 2, //Username and password |
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AUTH_UNACCEPTABLE = 0xff //No acceptable method found |
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}; |
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enum addrTypes |
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{ |
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ADDR_IPV4 = 1, //IPv4 address (4 octets) |
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ADDR_DNS = 3, // DNS name (up to 255 octets) |
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ADDR_IPV6 = 4 //IPV6 address (16 octets) |
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}; |
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enum errTypes |
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{ |
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SOCKS5_OK = 0, // No error for SOCKS5 |
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SOCKS5_GEN_FAIL = 1, // General server failure |
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SOCKS5_RULE_DENIED = 2, // Connection disallowed by ruleset |
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SOCKS5_NET_UNREACH = 3, // Network unreachable |
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SOCKS5_HOST_UNREACH = 4, // Host unreachable |
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SOCKS5_CONN_REFUSED = 5, // Connection refused by the peer |
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SOCKS5_TTL_EXPIRED = 6, // TTL Expired |
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SOCKS5_CMD_UNSUP = 7, // Command unsupported |
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SOCKS5_ADDR_UNSUP = 8, // Address type unsupported |
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SOCKS4_OK = 90, // No error for SOCKS4 |
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SOCKS4_FAIL = 91, // Failed establishing connecting or not allowed |
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SOCKS4_IDENTD_MISSING = 92, // Couldn't connect to the identd server |
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SOCKS4_IDENTD_DIFFER = 93 // The ID reported by the application and by identd differ |
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}; |
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enum cmdTypes |
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{ |
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CMD_CONNECT = 1, // TCP Connect |
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CMD_BIND = 2, // TCP Bind |
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CMD_UDP = 3 // UDP associate |
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}; |
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enum socksVersions |
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{ |
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SOCKS4 = 4, // SOCKS4 |
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SOCKS5 = 5 // SOCKS5 |
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}; |
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union address |
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{ |
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uint32_t ip; |
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SOCKSDnsAddress dns; |
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uint8_t ipv6[16]; |
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}; |
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void EnterState(state nstate, uint8_t parseleft = 1); |
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bool HandleData(uint8_t *sock_buff, std::size_t len); |
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bool ValidateSOCKSRequest(); |
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void HandleSockRecv(const boost::system::error_code & ecode, std::size_t bytes_transfered); |
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void Terminate(); |
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void AsyncSockRead(); |
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boost::asio::const_buffers_1 GenerateSOCKS5SelectAuth(authMethods method); |
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boost::asio::const_buffers_1 GenerateSOCKS4Response(errTypes error, uint32_t ip, uint16_t port); |
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boost::asio::const_buffers_1 GenerateSOCKS5Response(errTypes error, addrTypes type, const address &addr, uint16_t port); |
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bool Socks5ChooseAuth(); |
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void Socks5UserPasswdResponse (); |
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void SocksRequestFailed(errTypes error); |
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void SocksRequestSuccess(); |
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void SentSocksFailed(const boost::system::error_code & ecode); |
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void SentSocksDone(const boost::system::error_code & ecode); |
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void SentSocksResponse(const boost::system::error_code & ecode); |
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void HandleStreamRequestComplete (std::shared_ptr<i2p::stream::Stream> stream); |
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void ForwardSOCKS(); |
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template<typename Socket> |
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void SocksUpstreamSuccess(std::shared_ptr<Socket>& upstreamSock); |
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void AsyncUpstreamSockRead(); |
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template<typename Socket> |
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void SendUpstreamRequest(std::shared_ptr<Socket>& upstreamSock); |
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void HandleUpstreamConnected(const boost::system::error_code & ecode, |
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boost::asio::ip::tcp::resolver::iterator itr); |
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void HandleUpstreamResolved(const boost::system::error_code & ecode, |
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boost::asio::ip::tcp::resolver::iterator itr); |
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boost::asio::ip::tcp::resolver m_proxy_resolver; |
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uint8_t m_sock_buff[socks_buffer_size]; |
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std::shared_ptr<boost::asio::ip::tcp::socket> m_sock, m_upstreamSock; |
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#if defined(BOOST_ASIO_HAS_LOCAL_SOCKETS) |
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std::shared_ptr<boost::asio::local::stream_protocol::socket> m_upstreamLocalSock; |
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#endif |
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std::shared_ptr<i2p::stream::Stream> m_stream; |
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uint8_t *m_remaining_data; //Data left to be sent |
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uint8_t *m_remaining_upstream_data; //upstream data left to be forwarded |
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uint8_t m_response[7+max_socks_hostname_size]; |
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address m_address; //Address |
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std::size_t m_remaining_data_len; //Size of the data left to be sent |
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uint32_t m_4aip; //Used in 4a requests |
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uint16_t m_port; |
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uint8_t m_command; |
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uint8_t m_parseleft; //Octets left to parse |
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authMethods m_authchosen; //Authentication chosen |
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addrTypes m_addrtype; //Address type chosen |
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socksVersions m_socksv; //Socks version |
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cmdTypes m_cmd; // Command requested |
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state m_state; |
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const bool m_UseUpstreamProxy; // do we want to use the upstream proxy for non i2p addresses? |
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const std::string m_UpstreamProxyAddress; |
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const uint16_t m_UpstreamProxyPort; |
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public: |
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SOCKSHandler(SOCKSServer * parent, std::shared_ptr<boost::asio::ip::tcp::socket> sock, const std::string & upstreamAddr, const uint16_t upstreamPort, const bool useUpstream) : |
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I2PServiceHandler(parent), |
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m_proxy_resolver(parent->GetService()), |
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m_sock(sock), m_stream(nullptr), |
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m_authchosen(AUTH_UNACCEPTABLE), m_addrtype(ADDR_IPV4), |
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m_UseUpstreamProxy(useUpstream), |
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m_UpstreamProxyAddress(upstreamAddr), |
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m_UpstreamProxyPort(upstreamPort) |
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{ m_address.ip = 0; EnterState(GET_SOCKSV); } |
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~SOCKSHandler() { Terminate(); } |
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void Handle() { AsyncSockRead(); } |
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}; |
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void SOCKSHandler::AsyncSockRead() |
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{ |
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LogPrint(eLogDebug, "SOCKS: Async sock read"); |
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if (m_sock) { |
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m_sock->async_receive(boost::asio::buffer(m_sock_buff, socks_buffer_size), |
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std::bind(&SOCKSHandler::HandleSockRecv, shared_from_this(), |
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std::placeholders::_1, std::placeholders::_2)); |
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} else { |
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LogPrint(eLogError,"SOCKS: No socket for read"); |
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} |
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} |
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void SOCKSHandler::Terminate() |
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{ |
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if (Kill()) return; |
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if (m_sock) |
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{ |
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LogPrint(eLogDebug, "SOCKS: Closing socket"); |
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m_sock->close(); |
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m_sock = nullptr; |
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} |
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if (m_upstreamSock) |
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{ |
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LogPrint(eLogDebug, "SOCKS: Closing upstream socket"); |
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m_upstreamSock->close(); |
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m_upstreamSock = nullptr; |
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} |
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#if defined(BOOST_ASIO_HAS_LOCAL_SOCKETS) |
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if (m_upstreamLocalSock) |
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{ |
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LogPrint(eLogDebug, "SOCKS: Closing upstream local socket"); |
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m_upstreamLocalSock->close(); |
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m_upstreamLocalSock = nullptr; |
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} |
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#endif |
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if (m_stream) |
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{ |
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LogPrint(eLogDebug, "SOCKS: Closing stream"); |
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m_stream.reset (); |
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} |
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Done(shared_from_this()); |
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} |
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boost::asio::const_buffers_1 SOCKSHandler::GenerateSOCKS4Response(SOCKSHandler::errTypes error, uint32_t ip, uint16_t port) |
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{ |
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assert(error >= SOCKS4_OK); |
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m_response[0] = '\x00'; // version |
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m_response[1] = error; // response code |
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htobe16buf(m_response + 2, port); // port |
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htobe32buf(m_response + 4, ip); // IP |
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return boost::asio::const_buffers_1(m_response,8); |
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} |
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boost::asio::const_buffers_1 SOCKSHandler::GenerateSOCKS5Response(SOCKSHandler::errTypes error, SOCKSHandler::addrTypes type, const SOCKSHandler::address &addr, uint16_t port) |
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{ |
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size_t size = 6; // header + port |
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assert(error <= SOCKS5_ADDR_UNSUP); |
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m_response[0] = '\x05'; // version |
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m_response[1] = error; // response code |
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m_response[2] = '\x00'; // reserved |
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m_response[3] = type; // address type |
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switch (type) |
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{ |
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case ADDR_IPV4: |
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size += 4; |
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htobe32buf(m_response + 4, addr.ip); |
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htobe16buf(m_response + size - 2, port); |
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break; |
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case ADDR_IPV6: |
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size += 16; |
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memcpy(m_response + 4, addr.ipv6, 16); |
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htobe16buf(m_response + size - 2, port); |
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break; |
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case ADDR_DNS: |
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std::string address(addr.dns.value, addr.dns.size); |
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if(address.substr(addr.dns.size - 4, 4) == ".i2p") // overwrite if requested address inside I2P |
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{ |
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m_response[3] = ADDR_IPV4; |
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size += 4; |
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memset(m_response + 4, 0, 6); // six HEX zeros |
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} |
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else |
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{ |
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size += (1 + addr.dns.size); /* name length + resolved address */ |
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m_response[4] = addr.dns.size; |
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memcpy(m_response + 5, addr.dns.value, addr.dns.size); |
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htobe16buf(m_response + size - 2, port); |
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} |
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break; |
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} |
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return boost::asio::const_buffers_1(m_response, size); |
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} |
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bool SOCKSHandler::Socks5ChooseAuth() |
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{ |
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m_response[0] = '\x05'; // Version |
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m_response[1] = m_authchosen; // Response code |
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boost::asio::const_buffers_1 response(m_response, 2); |
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if (m_authchosen == AUTH_UNACCEPTABLE) |
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{ |
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LogPrint(eLogWarning, "SOCKS: v5 authentication negotiation failed"); |
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boost::asio::async_write(*m_sock, response, std::bind(&SOCKSHandler::SentSocksFailed, shared_from_this(), std::placeholders::_1)); |
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return false; |
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} |
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else |
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{ |
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LogPrint(eLogDebug, "SOCKS: v5 choosing authentication method: ", m_authchosen); |
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boost::asio::async_write(*m_sock, response, std::bind(&SOCKSHandler::SentSocksResponse, shared_from_this(), std::placeholders::_1)); |
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return true; |
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} |
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} |
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void SOCKSHandler::Socks5UserPasswdResponse () |
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{ |
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m_response[0] = 1; // Version of the subnegotiation |
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m_response[1] = 0; // Response code |
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LogPrint(eLogDebug, "SOCKS: v5 user/password response"); |
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boost::asio::async_write(*m_sock, boost::asio::const_buffers_1(m_response, 2), |
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std::bind(&SOCKSHandler::SentSocksResponse, shared_from_this(), std::placeholders::_1)); |
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} |
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/* All hope is lost beyond this point */ |
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void SOCKSHandler::SocksRequestFailed(SOCKSHandler::errTypes error) |
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{ |
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boost::asio::const_buffers_1 response(nullptr,0); |
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assert(error != SOCKS4_OK && error != SOCKS5_OK); |
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switch (m_socksv) |
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{ |
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case SOCKS4: |
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LogPrint(eLogWarning, "SOCKS: v4 request failed: ", error); |
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if (error < SOCKS4_OK) error = SOCKS4_FAIL; // Transparently map SOCKS5 errors |
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response = GenerateSOCKS4Response(error, m_4aip, m_port); |
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break; |
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case SOCKS5: |
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LogPrint(eLogWarning, "SOCKS: v5 request failed: ", error); |
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response = GenerateSOCKS5Response(error, m_addrtype, m_address, m_port); |
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break; |
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} |
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boost::asio::async_write(*m_sock, response, std::bind(&SOCKSHandler::SentSocksFailed, |
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shared_from_this(), std::placeholders::_1)); |
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} |
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void SOCKSHandler::SocksRequestSuccess() |
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{ |
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boost::asio::const_buffers_1 response(nullptr,0); |
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// TODO: this should depend on things like the command type and callbacks may change |
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switch (m_socksv) |
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{ |
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case SOCKS4: |
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LogPrint(eLogInfo, "SOCKS: v4 connection success"); |
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response = GenerateSOCKS4Response(SOCKS4_OK, m_4aip, m_port); |
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break; |
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case SOCKS5: |
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LogPrint(eLogInfo, "SOCKS: v5 connection success"); |
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auto s = i2p::client::context.GetAddressBook().ToAddress(GetOwner()->GetLocalDestination()->GetIdentHash()); |
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address ad; ad.dns.FromString(s); |
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// HACK only 16 bits passed in port as SOCKS5 doesn't allow for more |
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response = GenerateSOCKS5Response(SOCKS5_OK, ADDR_DNS, ad, m_stream->GetRecvStreamID()); |
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break; |
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} |
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boost::asio::async_write(*m_sock, response, std::bind(&SOCKSHandler::SentSocksDone, shared_from_this(), std::placeholders::_1)); |
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} |
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void SOCKSHandler::EnterState(SOCKSHandler::state nstate, uint8_t parseleft) { |
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switch (nstate) |
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{ |
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case GET_PORT: parseleft = 2; break; |
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case GET_IPV4: m_addrtype = ADDR_IPV4; m_address.ip = 0; parseleft = 4; break; |
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case GET4_IDENT: m_4aip = m_address.ip; break; |
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case GET4A_HOST: |
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case GET5_HOST: m_addrtype = ADDR_DNS; m_address.dns.size = 0; break; |
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case GET5_IPV6: m_addrtype = ADDR_IPV6; parseleft = 16; break; |
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default:; |
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} |
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m_parseleft = parseleft; |
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m_state = nstate; |
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} |
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bool SOCKSHandler::ValidateSOCKSRequest() |
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{ |
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if ( m_cmd != CMD_CONNECT ) |
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{ |
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// TODO: we need to support binds and other shit! |
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LogPrint(eLogError, "SOCKS: Unsupported command: ", m_cmd); |
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SocksRequestFailed(SOCKS5_CMD_UNSUP); |
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return false; |
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} |
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// TODO: we may want to support other address types! |
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if ( m_addrtype != ADDR_DNS ) |
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{ |
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switch (m_socksv) |
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{ |
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case SOCKS5: |
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LogPrint(eLogError, "SOCKS: v5 unsupported address type: ", m_addrtype); |
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break; |
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case SOCKS4: |
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LogPrint(eLogError, "SOCKS: Request with v4a rejected because it's actually SOCKS4"); |
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break; |
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} |
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SocksRequestFailed(SOCKS5_ADDR_UNSUP); |
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return false; |
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} |
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return true; |
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} |
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bool SOCKSHandler::HandleData(uint8_t *sock_buff, std::size_t len) |
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{ |
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assert(len); // This should always be called with a least a byte left to parse |
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while (len > 0) |
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{ |
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switch (m_state) |
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{ |
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case GET_SOCKSV: |
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m_socksv = (SOCKSHandler::socksVersions) *sock_buff; |
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switch (*sock_buff) |
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{ |
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case SOCKS4: |
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EnterState(GET_COMMAND); //Initialize the parser at the right position |
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break; |
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case SOCKS5: |
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EnterState(GET5_AUTHNUM); //Initialize the parser at the right position |
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break; |
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default: |
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LogPrint(eLogError, "SOCKS: Rejected invalid version: ", ((int)*sock_buff)); |
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Terminate(); |
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return false; |
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} |
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break; |
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case GET5_AUTHNUM: |
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EnterState(GET5_AUTH, *sock_buff); |
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break; |
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case GET5_AUTH: |
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m_parseleft --; |
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if (*sock_buff == AUTH_NONE) |
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m_authchosen = AUTH_NONE; |
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else if (*sock_buff == AUTH_USERPASSWD) |
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m_authchosen = AUTH_USERPASSWD; |
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if ( m_parseleft == 0 ) |
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{ |
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if (!Socks5ChooseAuth()) return false; |
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if (m_authchosen == AUTH_USERPASSWD) |
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EnterState(GET5_USERPASSWD); |
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else |
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EnterState(GET5_REQUESTV); |
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} |
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break; |
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case GET_COMMAND: |
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switch (*sock_buff) |
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{ |
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case CMD_CONNECT: |
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case CMD_BIND: |
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break; |
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case CMD_UDP: |
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if (m_socksv == SOCKS5) break; |
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#if (__cplusplus >= 201703L) // C++ 17 or higher |
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[[fallthrough]]; |
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#endif |
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default: |
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LogPrint(eLogError, "SOCKS: Invalid command: ", ((int)*sock_buff)); |
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SocksRequestFailed(SOCKS5_GEN_FAIL); |
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return false; |
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} |
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m_cmd = (SOCKSHandler::cmdTypes)*sock_buff; |
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switch (m_socksv) |
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{ |
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case SOCKS5: EnterState(GET5_GETRSV); break; |
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case SOCKS4: EnterState(GET_PORT); break; |
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} |
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break; |
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case GET_PORT: |
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m_port = (m_port << 8)|((uint16_t)*sock_buff); |
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m_parseleft--; |
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if (m_parseleft == 0) |
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{ |
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switch (m_socksv) |
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{ |
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case SOCKS5: EnterState(READY); break; |
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case SOCKS4: EnterState(GET_IPV4); break; |
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} |
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} |
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break; |
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case GET_IPV4: |
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m_address.ip = (m_address.ip << 8)|((uint32_t)*sock_buff); |
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m_parseleft--; |
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if (m_parseleft == 0) |
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{ |
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switch (m_socksv) |
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{ |
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case SOCKS5: EnterState(GET_PORT); break; |
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case SOCKS4: EnterState(GET4_IDENT); m_4aip = m_address.ip; break; |
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} |
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} |
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break; |
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case GET4_IDENT: |
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if (!*sock_buff) |
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{ |
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if( m_4aip == 0 || m_4aip > 255 ) |
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EnterState(READY); |
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else |
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EnterState(GET4A_HOST); |
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} |
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break; |
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case GET4A_HOST: |
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if (!*sock_buff) |
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{ |
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EnterState(READY); |
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break; |
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} |
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if (m_address.dns.size >= max_socks_hostname_size) |
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{ |
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LogPrint(eLogError, "SOCKS: v4a req failed: destination is too large"); |
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SocksRequestFailed(SOCKS4_FAIL); |
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return false; |
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} |
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m_address.dns.push_back(*sock_buff); |
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break; |
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case GET5_REQUESTV: |
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if (*sock_buff != SOCKS5) |
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{ |
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LogPrint(eLogError,"SOCKS: v5 rejected unknown request version: ", ((int)*sock_buff)); |
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SocksRequestFailed(SOCKS5_GEN_FAIL); |
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return false; |
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} |
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EnterState(GET_COMMAND); |
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break; |
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case GET5_GETRSV: |
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if ( *sock_buff != 0 ) |
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{ |
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LogPrint(eLogError, "SOCKS: v5 unknown reserved field: ", ((int)*sock_buff)); |
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SocksRequestFailed(SOCKS5_GEN_FAIL); |
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return false; |
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} |
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EnterState(GET5_GETADDRTYPE); |
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break; |
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case GET5_GETADDRTYPE: |
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switch (*sock_buff) |
|
{ |
|
case ADDR_IPV4: EnterState(GET_IPV4); break; |
|
case ADDR_IPV6: EnterState(GET5_IPV6); break; |
|
case ADDR_DNS : EnterState(GET5_HOST_SIZE); break; |
|
default: |
|
LogPrint(eLogError, "SOCKS: v5 unknown address type: ", ((int)*sock_buff)); |
|
SocksRequestFailed(SOCKS5_GEN_FAIL); |
|
return false; |
|
} |
|
break; |
|
case GET5_IPV6: |
|
m_address.ipv6[16-m_parseleft] = *sock_buff; |
|
m_parseleft--; |
|
if (m_parseleft == 0) EnterState(GET_PORT); |
|
break; |
|
case GET5_HOST_SIZE: |
|
EnterState(GET5_HOST, *sock_buff); |
|
break; |
|
case GET5_HOST: |
|
m_address.dns.push_back(*sock_buff); |
|
m_parseleft--; |
|
if (m_parseleft == 0) EnterState(GET_PORT); |
|
break; |
|
case GET5_USERPASSWD: |
|
if (*sock_buff != 1) |
|
{ |
|
LogPrint(eLogError,"SOCKS: v5 rejected invalid username/password subnegotiation: ", ((int)*sock_buff)); |
|
SocksRequestFailed(SOCKS5_GEN_FAIL); |
|
return false; |
|
} |
|
EnterState(GET5_USER_SIZE); |
|
break; |
|
case GET5_USER_SIZE: |
|
if (*sock_buff) |
|
EnterState(GET5_USER, *sock_buff); |
|
else // empty user |
|
EnterState(GET5_PASSWD_SIZE); |
|
break; |
|
case GET5_USER: |
|
// skip user for now |
|
m_parseleft--; |
|
if (m_parseleft == 0) EnterState(GET5_PASSWD_SIZE); |
|
break; |
|
case GET5_PASSWD_SIZE: |
|
if (*sock_buff) |
|
EnterState(GET5_PASSWD, *sock_buff); |
|
else // empty password |
|
{ |
|
Socks5UserPasswdResponse (); |
|
EnterState(GET5_REQUESTV); |
|
} |
|
break; |
|
case GET5_PASSWD: |
|
// skip passwd for now |
|
m_parseleft--; |
|
if (m_parseleft == 0) |
|
{ |
|
Socks5UserPasswdResponse (); |
|
EnterState(GET5_REQUESTV); |
|
} |
|
break; |
|
default: |
|
LogPrint(eLogError, "SOCKS: Parse state?? ", m_state); |
|
Terminate(); |
|
return false; |
|
} |
|
sock_buff++; |
|
len--; |
|
if (m_state == READY) |
|
{ |
|
m_remaining_data_len = len; |
|
m_remaining_data = sock_buff; |
|
return ValidateSOCKSRequest(); |
|
} |
|
} |
|
return true; |
|
} |
|
|
|
void SOCKSHandler::HandleSockRecv(const boost::system::error_code & ecode, std::size_t len) |
|
{ |
|
LogPrint(eLogDebug, "SOCKS: Received ", len, " bytes"); |
|
if(ecode) |
|
{ |
|
LogPrint(eLogWarning, "SOCKS: Recv got error: ", ecode); |
|
Terminate(); |
|
return; |
|
} |
|
|
|
if (HandleData(m_sock_buff, len)) |
|
{ |
|
if (m_state == READY) |
|
{ |
|
const std::string addr = m_address.dns.ToString(); |
|
LogPrint(eLogInfo, "SOCKS: Requested ", addr, ":" , m_port); |
|
const size_t addrlen = addr.size(); |
|
// does it end with .i2p? |
|
if ( addr.rfind(".i2p") == addrlen - 4) { |
|
// yes it does, make an i2p session |
|
GetOwner()->CreateStream ( std::bind (&SOCKSHandler::HandleStreamRequestComplete, |
|
shared_from_this(), std::placeholders::_1), m_address.dns.ToString(), m_port); |
|
} else if (m_UseUpstreamProxy) { |
|
// forward it to upstream proxy |
|
ForwardSOCKS(); |
|
} else { |
|
// no upstream proxy |
|
SocksRequestFailed(SOCKS5_ADDR_UNSUP); |
|
} |
|
} |
|
else |
|
AsyncSockRead(); |
|
} |
|
} |
|
|
|
void SOCKSHandler::SentSocksFailed(const boost::system::error_code & ecode) |
|
{ |
|
if (ecode) |
|
LogPrint (eLogError, "SOCKS: Closing socket after sending failure because: ", ecode.message ()); |
|
Terminate(); |
|
} |
|
|
|
void SOCKSHandler::SentSocksDone(const boost::system::error_code & ecode) |
|
{ |
|
if (!ecode) |
|
{ |
|
if (Kill()) return; |
|
LogPrint (eLogInfo, "SOCKS: New I2PTunnel connection"); |
|
auto connection = std::make_shared<i2p::client::I2PTunnelConnection>(GetOwner(), m_sock, m_stream); |
|
GetOwner()->AddHandler (connection); |
|
connection->I2PConnect (m_remaining_data,m_remaining_data_len); |
|
Done(shared_from_this()); |
|
} |
|
else |
|
{ |
|
LogPrint (eLogError, "SOCKS: Closing socket after completion reply because: ", ecode.message ()); |
|
Terminate(); |
|
} |
|
} |
|
|
|
void SOCKSHandler::SentSocksResponse(const boost::system::error_code & ecode) |
|
{ |
|
if (ecode) |
|
{ |
|
LogPrint (eLogError, "SOCKS: Closing socket after sending reply because: ", ecode.message ()); |
|
Terminate(); |
|
} |
|
} |
|
|
|
void SOCKSHandler::HandleStreamRequestComplete (std::shared_ptr<i2p::stream::Stream> stream) |
|
{ |
|
if (stream) |
|
{ |
|
m_stream = stream; |
|
SocksRequestSuccess(); |
|
} |
|
else |
|
{ |
|
LogPrint (eLogError, "SOCKS: Error when creating the stream, check the previous warnings for more info"); |
|
SocksRequestFailed(SOCKS5_HOST_UNREACH); |
|
} |
|
} |
|
|
|
void SOCKSHandler::ForwardSOCKS() |
|
{ |
|
LogPrint(eLogInfo, "SOCKS: Forwarding to upstream"); |
|
if (m_UpstreamProxyPort) // TCP |
|
{ |
|
EnterState(UPSTREAM_RESOLVE); |
|
boost::asio::ip::tcp::resolver::query q(m_UpstreamProxyAddress, std::to_string(m_UpstreamProxyPort)); |
|
m_proxy_resolver.async_resolve(q, std::bind(&SOCKSHandler::HandleUpstreamResolved, shared_from_this(), |
|
std::placeholders::_1, std::placeholders::_2)); |
|
} |
|
else if (!m_UpstreamProxyAddress.empty ())// local |
|
{ |
|
#if defined(BOOST_ASIO_HAS_LOCAL_SOCKETS) |
|
EnterState(UPSTREAM_CONNECT); |
|
m_upstreamLocalSock = std::make_shared<boost::asio::local::stream_protocol::socket>(GetOwner()->GetService()); |
|
auto s = shared_from_this (); |
|
m_upstreamLocalSock->async_connect(m_UpstreamProxyAddress, |
|
[s](const boost::system::error_code& ecode) |
|
{ |
|
if (ecode) |
|
{ |
|
LogPrint(eLogWarning, "SOCKS: Could not connect to local upstream proxy: ", ecode.message()); |
|
s->SocksRequestFailed(SOCKS5_NET_UNREACH); |
|
return; |
|
} |
|
LogPrint(eLogInfo, "SOCKS: Connected to local upstream proxy"); |
|
s->SendUpstreamRequest(s->m_upstreamLocalSock); |
|
}); |
|
#else |
|
LogPrint(eLogError, "SOCKS: Local sockets for upstream proxy not supported"); |
|
SocksRequestFailed(SOCKS5_ADDR_UNSUP); |
|
#endif |
|
} |
|
else |
|
{ |
|
LogPrint(eLogError, "SOCKS: Incorrect upstream proxy address"); |
|
SocksRequestFailed(SOCKS5_ADDR_UNSUP); |
|
} |
|
} |
|
|
|
template<typename Socket> |
|
void SOCKSHandler::SocksUpstreamSuccess(std::shared_ptr<Socket>& upstreamSock) |
|
{ |
|
LogPrint(eLogInfo, "SOCKS: Upstream success"); |
|
boost::asio::const_buffers_1 response(nullptr, 0); |
|
switch (m_socksv) |
|
{ |
|
case SOCKS4: |
|
LogPrint(eLogInfo, "SOCKS: v4 connection success"); |
|
response = GenerateSOCKS4Response(SOCKS4_OK, m_4aip, m_port); |
|
break; |
|
case SOCKS5: |
|
LogPrint(eLogInfo, "SOCKS: v5 connection success"); |
|
//HACK only 16 bits passed in port as SOCKS5 doesn't allow for more |
|
response = GenerateSOCKS5Response(SOCKS5_OK, ADDR_DNS, m_address, m_port); |
|
break; |
|
} |
|
m_sock->send(response); |
|
auto forwarder = CreateSocketsPipe (GetOwner(), m_sock, upstreamSock); |
|
upstreamSock = nullptr; |
|
m_sock = nullptr; |
|
GetOwner()->AddHandler(forwarder); |
|
forwarder->Start(); |
|
Terminate(); |
|
} |
|
|
|
template<typename Socket> |
|
void SOCKSHandler::SendUpstreamRequest(std::shared_ptr<Socket>& upstreamSock) |
|
{ |
|
LogPrint(eLogInfo, "SOCKS: Negotiating with upstream proxy"); |
|
EnterState(UPSTREAM_HANDSHAKE); |
|
if (upstreamSock) |
|
{ |
|
auto s = shared_from_this (); |
|
i2p::transport::Socks5Handshake (*upstreamSock, std::make_pair(m_address.dns.ToString (), m_port), |
|
[s, &upstreamSock](const boost::system::error_code& ec) |
|
{ |
|
if (!ec) |
|
s->SocksUpstreamSuccess(upstreamSock); |
|
else |
|
{ |
|
s->SocksRequestFailed(SOCKS5_NET_UNREACH); |
|
LogPrint(eLogError, "SOCKS: Upstream proxy failure: ", ec.message ()); |
|
} |
|
}); |
|
} |
|
else |
|
LogPrint(eLogError, "SOCKS: No upstream socket to send handshake to"); |
|
} |
|
|
|
void SOCKSHandler::HandleUpstreamConnected(const boost::system::error_code & ecode, boost::asio::ip::tcp::resolver::iterator itr) |
|
{ |
|
if (ecode) { |
|
LogPrint(eLogWarning, "SOCKS: Could not connect to upstream proxy: ", ecode.message()); |
|
SocksRequestFailed(SOCKS5_NET_UNREACH); |
|
return; |
|
} |
|
LogPrint(eLogInfo, "SOCKS: Connected to upstream proxy"); |
|
SendUpstreamRequest(m_upstreamSock); |
|
} |
|
|
|
void SOCKSHandler::HandleUpstreamResolved(const boost::system::error_code & ecode, boost::asio::ip::tcp::resolver::iterator itr) |
|
{ |
|
if (ecode) { |
|
// error resolving |
|
LogPrint(eLogWarning, "SOCKS: Upstream proxy", m_UpstreamProxyAddress, " not resolved: ", ecode.message()); |
|
SocksRequestFailed(SOCKS5_NET_UNREACH); |
|
return; |
|
} |
|
LogPrint(eLogInfo, "SOCKS: Upstream proxy resolved"); |
|
EnterState(UPSTREAM_CONNECT); |
|
auto & service = GetOwner()->GetService(); |
|
m_upstreamSock = std::make_shared<boost::asio::ip::tcp::socket>(service); |
|
boost::asio::async_connect(*m_upstreamSock, itr, |
|
std::bind(&SOCKSHandler::HandleUpstreamConnected, |
|
shared_from_this(), std::placeholders::_1, std::placeholders::_2)); |
|
} |
|
|
|
SOCKSServer::SOCKSServer(const std::string& name, const std::string& address, uint16_t port, |
|
bool outEnable, const std::string& outAddress, uint16_t outPort, |
|
std::shared_ptr<i2p::client::ClientDestination> localDestination) : |
|
TCPIPAcceptor (address, port, localDestination ? localDestination : i2p::client::context.GetSharedLocalDestination ()), m_Name (name) |
|
{ |
|
m_UseUpstreamProxy = false; |
|
if (outAddress.length() > 0 && outEnable) |
|
SetUpstreamProxy(outAddress, outPort); |
|
} |
|
|
|
std::shared_ptr<i2p::client::I2PServiceHandler> SOCKSServer::CreateHandler(std::shared_ptr<boost::asio::ip::tcp::socket> socket) |
|
{ |
|
return std::make_shared<SOCKSHandler> (this, socket, m_UpstreamProxyAddress, m_UpstreamProxyPort, m_UseUpstreamProxy); |
|
} |
|
|
|
void SOCKSServer::SetUpstreamProxy(const std::string & addr, const uint16_t port) |
|
{ |
|
m_UpstreamProxyAddress = addr; |
|
m_UpstreamProxyPort = port; |
|
m_UseUpstreamProxy = true; |
|
} |
|
} |
|
}
|
|
|