From 6cb9b5a231d7f41e409daa012ee7d50a52c65daa Mon Sep 17 00:00:00 2001 From: Robin Tarsiger Date: Sun, 3 Apr 2016 15:00:29 -0500 Subject: Split "proxies" into "proxy_dialers" and "modes" Half of the packages in there registered dialer types with golang.org/x/net/proxy, and half of them were proxying modes for the program as a whole. These are separate things, so move them into separate directories. --- modes/pt_socks5/pt_socks5.go | 303 ++++++++++++++++++++++++++ modes/transparent_tcp/transparent_tcp.go | 359 +++++++++++++++++++++++++++++++ modes/transparent_udp/transparent_udp.go | 343 +++++++++++++++++++++++++++++ 3 files changed, 1005 insertions(+) create mode 100644 modes/pt_socks5/pt_socks5.go create mode 100644 modes/transparent_tcp/transparent_tcp.go create mode 100644 modes/transparent_udp/transparent_udp.go (limited to 'modes') diff --git a/modes/pt_socks5/pt_socks5.go b/modes/pt_socks5/pt_socks5.go new file mode 100644 index 0000000..579124f --- /dev/null +++ b/modes/pt_socks5/pt_socks5.go @@ -0,0 +1,303 @@ +/* + * Copyright (c) 2014-2015, Yawning Angel + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * * Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * + * * Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +// Go language Tor Pluggable Transport suite. Works only as a managed +// client/server. +package pt_socks5 + +import ( + "fmt" + "io" + golog "log" + "net" + "net/url" + "sync" + + "golang.org/x/net/proxy" + + "git.torproject.org/pluggable-transports/goptlib.git" + "github.com/OperatorFoundation/obfs4/common/log" + "github.com/OperatorFoundation/obfs4/common/pt_extras" + "github.com/OperatorFoundation/obfs4/common/socks5" + "github.com/OperatorFoundation/obfs4/common/termmon" + "github.com/OperatorFoundation/obfs4/transports" + "github.com/OperatorFoundation/obfs4/transports/base" +) + +const ( + obfs4proxyVersion = "0.0.7-dev" + obfs4proxyLogFile = "obfs4proxy.log" + socksAddr = "127.0.0.1:0" +) + +var stateDir string + +func ClientSetup(termMon *termmon.TermMonitor) (launched bool, listeners []net.Listener) { + ptClientInfo, err := pt.ClientSetup(transports.Transports()) + if err != nil { + golog.Fatal(err) + } + + ptClientProxy, err := pt_extras.PtGetProxy() + fmt.Println("ptclientproxy", ptClientProxy) + if err != nil { + golog.Fatal(err) + } else if ptClientProxy != nil { + pt_extras.PtProxyDone() + } + + // Launch each of the client listeners. + for _, name := range ptClientInfo.MethodNames { + t := transports.Get(name) + if t == nil { + pt.CmethodError(name, "no such transport is supported") + continue + } + + f, err := t.ClientFactory(stateDir) + if err != nil { + pt.CmethodError(name, "failed to get ClientFactory") + continue + } + + ln, err := net.Listen("tcp", socksAddr) + if err != nil { + pt.CmethodError(name, err.Error()) + continue + } + + go clientAcceptLoop(termMon, f, ln, ptClientProxy) + pt.Cmethod(name, socks5.Version(), ln.Addr()) + + log.Infof("%s - registered listener: %s", name, ln.Addr()) + + listeners = append(listeners, ln) + launched = true + } + pt.CmethodsDone() + + return +} + +func clientAcceptLoop(termMon *termmon.TermMonitor, f base.ClientFactory, ln net.Listener, proxyURI *url.URL) error { + defer ln.Close() + for { + conn, err := ln.Accept() + if err != nil { + if e, ok := err.(net.Error); ok && !e.Temporary() { + return err + } + continue + } + go clientHandler(termMon, f, conn, proxyURI) + } +} + +func clientHandler(termMon *termmon.TermMonitor, f base.ClientFactory, conn net.Conn, proxyURI *url.URL) { + defer conn.Close() + termMon.OnHandlerStart() + defer termMon.OnHandlerFinish() + + name := f.Transport().Name() + + // Read the client's SOCKS handshake. + socksReq, err := socks5.Handshake(conn) + if err != nil { + log.Errorf("%s - client failed socks handshake: %s", name, err) + return + } + addrStr := log.ElideAddr(socksReq.Target) + + // Deal with arguments. + args, err := f.ParseArgs(&socksReq.Args) + if err != nil { + log.Errorf("%s(%s) - invalid arguments: %s", name, addrStr, err) + socksReq.Reply(socks5.ReplyGeneralFailure) + return + } + + // Obtain the proxy dialer if any, and create the outgoing TCP connection. + dialFn := proxy.Direct.Dial + if proxyURI != nil { + dialer, err := proxy.FromURL(proxyURI, proxy.Direct) + if err != nil { + // This should basically never happen, since config protocol + // verifies this. + log.Errorf("%s(%s) - failed to obtain proxy dialer: %s", name, addrStr, log.ElideError(err)) + socksReq.Reply(socks5.ReplyGeneralFailure) + return + } + dialFn = dialer.Dial + } + + fmt.Println("Got dialer", dialFn, proxyURI, proxy.Direct) + + remote, err := f.Dial("tcp", socksReq.Target, dialFn, args) + if err != nil { + log.Errorf("%s(%s) - outgoing connection failed: %s", name, addrStr, log.ElideError(err)) + socksReq.Reply(socks5.ErrorToReplyCode(err)) + return + } + defer remote.Close() + err = socksReq.Reply(socks5.ReplySucceeded) + if err != nil { + log.Errorf("%s(%s) - SOCKS reply failed: %s", name, addrStr, log.ElideError(err)) + return + } + + if err = copyLoop(conn, remote); err != nil { + log.Warnf("%s(%s) - closed connection: %s", name, addrStr, log.ElideError(err)) + } else { + log.Infof("%s(%s) - closed connection", name, addrStr) + } + + return +} + +func ServerSetup(termMon *termmon.TermMonitor) (launched bool, listeners []net.Listener) { + ptServerInfo, err := pt.ServerSetup(transports.Transports()) + if err != nil { + golog.Fatal(err) + } + + for _, bindaddr := range ptServerInfo.Bindaddrs { + name := bindaddr.MethodName + t := transports.Get(name) + if t == nil { + pt.SmethodError(name, "no such transport is supported") + continue + } + + f, err := t.ServerFactory(stateDir, &bindaddr.Options) + if err != nil { + pt.SmethodError(name, err.Error()) + continue + } + + ln, err := net.ListenTCP("tcp", bindaddr.Addr) + if err != nil { + pt.SmethodError(name, err.Error()) + continue + } + + go serverAcceptLoop(termMon, f, ln, &ptServerInfo) + if args := f.Args(); args != nil { + pt.SmethodArgs(name, ln.Addr(), *args) + } else { + pt.SmethodArgs(name, ln.Addr(), nil) + } + + log.Infof("%s - registered listener: %s", name, log.ElideAddr(ln.Addr().String())) + + listeners = append(listeners, ln) + launched = true + } + pt.SmethodsDone() + + return +} + +func serverAcceptLoop(termMon *termmon.TermMonitor, f base.ServerFactory, ln net.Listener, info *pt.ServerInfo) error { + defer ln.Close() + for { + conn, err := ln.Accept() + if err != nil { + if e, ok := err.(net.Error); ok && !e.Temporary() { + return err + } + continue + } + go serverHandler(termMon, f, conn, info) + } +} + +func serverHandler(termMon *termmon.TermMonitor, f base.ServerFactory, conn net.Conn, info *pt.ServerInfo) { + defer conn.Close() + termMon.OnHandlerStart() + defer termMon.OnHandlerFinish() + + name := f.Transport().Name() + addrStr := log.ElideAddr(conn.RemoteAddr().String()) + log.Infof("%s(%s) - new connection", name, addrStr) + + // Instantiate the server transport method and handshake. + remote, err := f.WrapConn(conn) + if err != nil { + log.Warnf("%s(%s) - handshake failed: %s", name, addrStr, log.ElideError(err)) + return + } + + // Connect to the orport. + orConn, err := pt.DialOr(info, conn.RemoteAddr().String(), name) + if err != nil { + log.Errorf("%s(%s) - failed to connect to ORPort: %s", name, addrStr, log.ElideError(err)) + return + } + defer orConn.Close() + + if err = copyLoop(orConn, remote); err != nil { + log.Warnf("%s(%s) - closed connection: %s", name, addrStr, log.ElideError(err)) + } else { + log.Infof("%s(%s) - closed connection", name, addrStr) + } + + return +} + +func copyLoop(a net.Conn, b net.Conn) error { + // Note: b is always the pt connection. a is the SOCKS/ORPort connection. + errChan := make(chan error, 2) + + var wg sync.WaitGroup + wg.Add(2) + + go func() { + defer wg.Done() + defer b.Close() + defer a.Close() + _, err := io.Copy(b, a) + errChan <- err + }() + go func() { + defer wg.Done() + defer a.Close() + defer b.Close() + _, err := io.Copy(a, b) + errChan <- err + }() + + // Wait for both upstream and downstream to close. Since one side + // terminating closes the other, the second error in the channel will be + // something like EINVAL (though io.Copy() will swallow EOF), so only the + // first error is returned. + wg.Wait() + if len(errChan) > 0 { + return <-errChan + } + + return nil +} diff --git a/modes/transparent_tcp/transparent_tcp.go b/modes/transparent_tcp/transparent_tcp.go new file mode 100644 index 0000000..0f27e3f --- /dev/null +++ b/modes/transparent_tcp/transparent_tcp.go @@ -0,0 +1,359 @@ +/* + * Copyright (c) 2014-2015, Yawning Angel + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * * Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * + * * Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +// Go language Tor Pluggable Transport suite. Works only as a managed +// client/server. +package transparent_tcp + +import ( + "fmt" + "io" + golog "log" + "net" + "net/url" + "strconv" + "strings" + "sync" + + "golang.org/x/net/proxy" + + "git.torproject.org/pluggable-transports/goptlib.git" + "github.com/OperatorFoundation/obfs4/common/log" + "github.com/OperatorFoundation/obfs4/common/termmon" + "github.com/OperatorFoundation/obfs4/transports" + "github.com/OperatorFoundation/obfs4/transports/base" +) + +const ( + obfs4proxyVersion = "0.0.7-dev" + obfs4proxyLogFile = "obfs4proxy.log" + socksAddr = "127.0.0.1:1234" +) + +var stateDir string + +func ClientSetup(termMon *termmon.TermMonitor, target string) (launched bool, listeners []net.Listener) { + methodNames := [...]string{"obfs2"} + var ptClientProxy *url.URL = nil + + // Launch each of the client listeners. + for _, name := range methodNames { + t := transports.Get(name) + if t == nil { + log.Errorf("no such transport is supported: %s", name) + continue + } + + f, err := t.ClientFactory(stateDir) + if err != nil { + log.Errorf("failed to get ClientFactory: %s", name) + continue + } + + fmt.Println("Listening ", socksAddr) + ln, err := net.Listen("tcp", socksAddr) + if err != nil { + log.Errorf("failed to listen %s %s", name, err.Error()) + continue + } + + go clientAcceptLoop(target, termMon, f, ln, ptClientProxy) + + log.Infof("%s - registered listener: %s", name, ln.Addr()) + + listeners = append(listeners, ln) + launched = true + } + + return +} + +func clientAcceptLoop(target string, termMon *termmon.TermMonitor, f base.ClientFactory, ln net.Listener, proxyURI *url.URL) error { + defer ln.Close() + for { + conn, err := ln.Accept() + fmt.Println("Accepted") + if err != nil { + if e, ok := err.(net.Error); ok && !e.Temporary() { + return err + } + continue + } + go clientHandler(target, termMon, f, conn, proxyURI) + } +} + +func clientHandler(target string, termMon *termmon.TermMonitor, f base.ClientFactory, conn net.Conn, proxyURI *url.URL) { + defer conn.Close() + termMon.OnHandlerStart() + defer termMon.OnHandlerFinish() + + fmt.Println("handling...") + + name := f.Transport().Name() + + fmt.Println("Transport is", name) + + // Deal with arguments. + args, err := f.ParseArgs(&pt.Args{}) + if err != nil { + fmt.Println("Invalid arguments") + log.Errorf("%s(%s) - invalid arguments: %s", name, target, err) + return + } + + fmt.Println("Making dialer...") + + // Obtain the proxy dialer if any, and create the outgoing TCP connection. + dialFn := proxy.Direct.Dial + if proxyURI != nil { + dialer, err := proxy.FromURL(proxyURI, proxy.Direct) + if err != nil { + // This should basically never happen, since config protocol + // verifies this. + fmt.Println("failed to obtain dialer", proxyURI, proxy.Direct) + log.Errorf("%s(%s) - failed to obtain proxy dialer: %s", name, target, log.ElideError(err)) + return + } + dialFn = dialer.Dial + } + + fmt.Println("Dialing...") + + remote, err := f.Dial("tcp", target, dialFn, args) + if err != nil { + fmt.Println("outgoing connection failed") + log.Errorf("%s(%s) - outgoing connection failed: %s", name, target, log.ElideError(err)) + return + } + defer remote.Close() + + fmt.Println("copying...") + + if err = copyLoop(conn, remote); err != nil { + log.Warnf("%s(%s) - closed connection: %s", name, target, log.ElideError(err)) + } else { + log.Infof("%s(%s) - closed connection", name, target) + } + + fmt.Println("done") + + return +} + +func ServerSetup(termMon *termmon.TermMonitor, bindaddrString string) (launched bool, listeners []net.Listener) { + ptServerInfo, err := pt.ServerSetup(transports.Transports()) + if err != nil { + golog.Fatal(err) + } + + fmt.Println("ServerSetup") + + bindaddrs, _ := getServerBindaddrs(bindaddrString) + + for _, bindaddr := range bindaddrs { + name := bindaddr.MethodName + fmt.Println("bindaddr", bindaddr) + t := transports.Get(name) + if t == nil { + fmt.Println(name, "no such transport is supported") + continue + } + + f, err := t.ServerFactory(stateDir, &bindaddr.Options) + if err != nil { + fmt.Println(name, err.Error()) + continue + } + + ln, err := net.ListenTCP("tcp", bindaddr.Addr) + if err != nil { + fmt.Println(name, err.Error()) + continue + } + + go serverAcceptLoop(termMon, f, ln, &ptServerInfo) + + log.Infof("%s - registered listener: %s", name, log.ElideAddr(ln.Addr().String())) + + listeners = append(listeners, ln) + launched = true + } + + return +} + +func getServerBindaddrs(serverBindaddr string) ([]pt.Bindaddr, error) { + var result []pt.Bindaddr + + for _, spec := range strings.Split(serverBindaddr, ",") { + var bindaddr pt.Bindaddr + + parts := strings.SplitN(spec, "-", 2) + if len(parts) != 2 { + fmt.Println("TOR_PT_SERVER_BINDADDR: doesn't contain \"-\"", spec) + return nil, nil + } + bindaddr.MethodName = parts[0] + addr, err := resolveAddr(parts[1]) + if err != nil { + fmt.Println("TOR_PT_SERVER_BINDADDR: ", spec, err.Error()) + return nil, nil + } + bindaddr.Addr = addr + // bindaddr.Options = optionsMap[bindaddr.MethodName] + result = append(result, bindaddr) + } + + return result, nil +} + +// Resolve an address string into a net.TCPAddr. We are a bit more strict than +// net.ResolveTCPAddr; we don't allow an empty host or port, and the host part +// must be a literal IP address. +func resolveAddr(addrStr string) (*net.TCPAddr, error) { + ipStr, portStr, err := net.SplitHostPort(addrStr) + if err != nil { + // Before the fixing of bug #7011, tor doesn't put brackets around IPv6 + // addresses. Split after the last colon, assuming it is a port + // separator, and try adding the brackets. + parts := strings.Split(addrStr, ":") + if len(parts) <= 2 { + return nil, err + } + addrStr := "[" + strings.Join(parts[:len(parts)-1], ":") + "]:" + parts[len(parts)-1] + ipStr, portStr, err = net.SplitHostPort(addrStr) + } + if err != nil { + return nil, err + } + if ipStr == "" { + return nil, net.InvalidAddrError(fmt.Sprintf("address string %q lacks a host part", addrStr)) + } + if portStr == "" { + return nil, net.InvalidAddrError(fmt.Sprintf("address string %q lacks a port part", addrStr)) + } + ip := net.ParseIP(ipStr) + if ip == nil { + return nil, net.InvalidAddrError(fmt.Sprintf("not an IP string: %q", ipStr)) + } + port, err := parsePort(portStr) + if err != nil { + return nil, err + } + return &net.TCPAddr{IP: ip, Port: port}, nil +} + +func parsePort(portStr string) (int, error) { + port, err := strconv.ParseUint(portStr, 10, 16) + return int(port), err +} + +func serverAcceptLoop(termMon *termmon.TermMonitor, f base.ServerFactory, ln net.Listener, info *pt.ServerInfo) error { + defer ln.Close() + for { + conn, err := ln.Accept() + fmt.Println("accepted") + if err != nil { + if e, ok := err.(net.Error); ok && !e.Temporary() { + return err + } + continue + } + go serverHandler(termMon, f, conn, info) + } +} + +func serverHandler(termMon *termmon.TermMonitor, f base.ServerFactory, conn net.Conn, info *pt.ServerInfo) { + defer conn.Close() + termMon.OnHandlerStart() + defer termMon.OnHandlerFinish() + + name := f.Transport().Name() + addrStr := log.ElideAddr(conn.RemoteAddr().String()) + fmt.Println("handling", name) + log.Infof("%s(%s) - new connection", name, addrStr) + + // Instantiate the server transport method and handshake. + remote, err := f.WrapConn(conn) + if err != nil { + fmt.Println("handshake failed") + log.Warnf("%s(%s) - handshake failed: %s", name, addrStr, log.ElideError(err)) + return + } + + // Connect to the orport. + orConn, err := pt.DialOr(info, conn.RemoteAddr().String(), name) + if err != nil { + fmt.Println("OR conn failed", info, conn.RemoteAddr(), name) + log.Errorf("%s(%s) - failed to connect to ORPort: %s", name, addrStr, log.ElideError(err)) + return + } + defer orConn.Close() + + if err = copyLoop(orConn, remote); err != nil { + log.Warnf("%s(%s) - closed connection: %s", name, addrStr, log.ElideError(err)) + } else { + log.Infof("%s(%s) - closed connection", name, addrStr) + } + + return +} + +func copyLoop(a net.Conn, b net.Conn) error { + // Note: b is always the pt connection. a is the SOCKS/ORPort connection. + errChan := make(chan error, 2) + + var wg sync.WaitGroup + wg.Add(2) + + go func() { + defer wg.Done() + defer b.Close() + defer a.Close() + _, err := io.Copy(b, a) + errChan <- err + }() + go func() { + defer wg.Done() + defer a.Close() + defer b.Close() + _, err := io.Copy(a, b) + errChan <- err + }() + + // Wait for both upstream and downstream to close. Since one side + // terminating closes the other, the second error in the channel will be + // something like EINVAL (though io.Copy() will swallow EOF), so only the + // first error is returned. + wg.Wait() + if len(errChan) > 0 { + return <-errChan + } + + return nil +} diff --git a/modes/transparent_udp/transparent_udp.go b/modes/transparent_udp/transparent_udp.go new file mode 100644 index 0000000..500cd55 --- /dev/null +++ b/modes/transparent_udp/transparent_udp.go @@ -0,0 +1,343 @@ +/* + * Copyright (c) 2014-2015, Yawning Angel + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * * Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * + * * Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +// Go language Tor Pluggable Transport suite. Works only as a managed +// client/server. +package transparent_udp + +import ( + "fmt" + "io" + golog "log" + "net" + "net/url" + "strconv" + "strings" + "sync" + + "golang.org/x/net/proxy" + + "git.torproject.org/pluggable-transports/goptlib.git" + "github.com/OperatorFoundation/obfs4/common/log" + "github.com/OperatorFoundation/obfs4/common/termmon" + "github.com/OperatorFoundation/obfs4/transports" + "github.com/OperatorFoundation/obfs4/transports/base" +) + +const ( + obfs4proxyVersion = "0.0.7-dev" + obfs4proxyLogFile = "obfs4proxy.log" + socksAddr = "127.0.0.1:1234" +) + +var stateDir string + +func ClientSetup(termMon *termmon.TermMonitor, target string) bool { + methodNames := [...]string{"obfs2"} + var ptClientProxy *url.URL = nil + + // Launch each of the client listeners. + for _, name := range methodNames { + t := transports.Get(name) + if t == nil { + log.Errorf("no such transport is supported: %s", name) + continue + } + + f, err := t.ClientFactory(stateDir) + if err != nil { + log.Errorf("failed to get ClientFactory: %s", name) + continue + } + + udpAddr, err := net.ResolveUDPAddr("udp", socksAddr) + if err != nil { + fmt.Println("Error resolving address", socksAddr) + } + + fmt.Println("Listening ", socksAddr) + ln, err := net.ListenUDP("udp", udpAddr) + if err != nil { + log.Errorf("failed to listen %s %s", name, err.Error()) + continue + } + + go clientHandler(target, termMon, f, ln, ptClientProxy) + + log.Infof("%s - registered listener: %s", name, ln) + } + + return true +} + +func clientHandler(target string, termMon *termmon.TermMonitor, f base.ClientFactory, conn net.Conn, proxyURI *url.URL) { + defer conn.Close() + termMon.OnHandlerStart() + defer termMon.OnHandlerFinish() + + fmt.Println("handling...") + + name := f.Transport().Name() + + fmt.Println("Transport is", name) + + // Deal with arguments. + args, err := f.ParseArgs(&pt.Args{}) + if err != nil { + fmt.Println("Invalid arguments") + log.Errorf("%s(%s) - invalid arguments: %s", name, target, err) + return + } + + fmt.Println("Making dialer...") + + // Obtain the proxy dialer if any, and create the outgoing TCP connection. + dialFn := proxy.Direct.Dial + if proxyURI != nil { + dialer, err := proxy.FromURL(proxyURI, proxy.Direct) + if err != nil { + // This should basically never happen, since config protocol + // verifies this. + fmt.Println("failed to obtain dialer", proxyURI, proxy.Direct) + log.Errorf("%s(%s) - failed to obtain proxy dialer: %s", name, target, log.ElideError(err)) + return + } + dialFn = dialer.Dial + } + + fmt.Println("Dialing...") + + remote, err := f.Dial("tcp", target, dialFn, args) + if err != nil { + fmt.Println("outgoing connection failed") + log.Errorf("%s(%s) - outgoing connection failed: %s", name, target, log.ElideError(err)) + return + } + defer remote.Close() + + fmt.Println("copying...") + + if err = copyLoopUDP(conn, remote); err != nil { + log.Warnf("%s(%s) - closed connection: %s", name, target, log.ElideError(err)) + } else { + log.Infof("%s(%s) - closed connection", name, target) + } + + fmt.Println("done") + + return +} + +func ServerSetup(termMon *termmon.TermMonitor, bindaddrString string) bool { + ptServerInfo, err := pt.ServerSetup(transports.Transports()) + if err != nil { + golog.Fatal(err) + } + + fmt.Println("ServerSetup") + + bindaddrs, _ := getServerBindaddrs(bindaddrString) + + for _, bindaddr := range bindaddrs { + name := bindaddr.MethodName + fmt.Println("bindaddr", bindaddr) + t := transports.Get(name) + if t == nil { + fmt.Println(name, "no such transport is supported") + continue + } + + f, err := t.ServerFactory(stateDir, &bindaddr.Options) + if err != nil { + fmt.Println(name, err.Error()) + continue + } + + ln, err := net.ListenTCP("tcp", bindaddr.Addr) + if err != nil { + fmt.Println(name, err.Error()) + continue + } + + go serverAcceptLoop(termMon, f, ln, &ptServerInfo) + + log.Infof("%s - registered listener: %s", name, log.ElideAddr(ln.Addr().String())) + } + + return true +} + +func getServerBindaddrs(serverBindaddr string) ([]pt.Bindaddr, error) { + var result []pt.Bindaddr + + for _, spec := range strings.Split(serverBindaddr, ",") { + var bindaddr pt.Bindaddr + + parts := strings.SplitN(spec, "-", 2) + if len(parts) != 2 { + fmt.Println("TOR_PT_SERVER_BINDADDR: doesn't contain \"-\"", spec) + return nil, nil + } + bindaddr.MethodName = parts[0] + addr, err := resolveAddr(parts[1]) + if err != nil { + fmt.Println("TOR_PT_SERVER_BINDADDR: ", spec, err.Error()) + return nil, nil + } + bindaddr.Addr = addr + // bindaddr.Options = optionsMap[bindaddr.MethodName] + result = append(result, bindaddr) + } + + return result, nil +} + +// Resolve an address string into a net.TCPAddr. We are a bit more strict than +// net.ResolveTCPAddr; we don't allow an empty host or port, and the host part +// must be a literal IP address. +func resolveAddr(addrStr string) (*net.TCPAddr, error) { + ipStr, portStr, err := net.SplitHostPort(addrStr) + if err != nil { + // Before the fixing of bug #7011, tor doesn't put brackets around IPv6 + // addresses. Split after the last colon, assuming it is a port + // separator, and try adding the brackets. + parts := strings.Split(addrStr, ":") + if len(parts) <= 2 { + return nil, err + } + addrStr := "[" + strings.Join(parts[:len(parts)-1], ":") + "]:" + parts[len(parts)-1] + ipStr, portStr, err = net.SplitHostPort(addrStr) + } + if err != nil { + return nil, err + } + if ipStr == "" { + return nil, net.InvalidAddrError(fmt.Sprintf("address string %q lacks a host part", addrStr)) + } + if portStr == "" { + return nil, net.InvalidAddrError(fmt.Sprintf("address string %q lacks a port part", addrStr)) + } + ip := net.ParseIP(ipStr) + if ip == nil { + return nil, net.InvalidAddrError(fmt.Sprintf("not an IP string: %q", ipStr)) + } + port, err := parsePort(portStr) + if err != nil { + return nil, err + } + return &net.TCPAddr{IP: ip, Port: port}, nil +} + +func parsePort(portStr string) (int, error) { + port, err := strconv.ParseUint(portStr, 10, 16) + return int(port), err +} + +func serverAcceptLoop(termMon *termmon.TermMonitor, f base.ServerFactory, ln net.Listener, info *pt.ServerInfo) error { + defer ln.Close() + for { + conn, err := ln.Accept() + fmt.Println("accepted") + if err != nil { + if e, ok := err.(net.Error); ok && !e.Temporary() { + return err + } + continue + } + go serverHandler(termMon, f, conn, info) + } +} + +func serverHandler(termMon *termmon.TermMonitor, f base.ServerFactory, conn net.Conn, info *pt.ServerInfo) { + defer conn.Close() + termMon.OnHandlerStart() + defer termMon.OnHandlerFinish() + + name := f.Transport().Name() + addrStr := log.ElideAddr(conn.RemoteAddr().String()) + fmt.Println("handling", name) + log.Infof("%s(%s) - new connection", name, addrStr) + + // Instantiate the server transport method and handshake. + remote, err := f.WrapConn(conn) + if err != nil { + fmt.Println("handshake failed") + log.Warnf("%s(%s) - handshake failed: %s", name, addrStr, log.ElideError(err)) + return + } + + // Connect to the orport. + orConn, err := pt.DialOr(info, conn.RemoteAddr().String(), name) + if err != nil { + fmt.Println("OR conn failed", info, conn.RemoteAddr(), name) + log.Errorf("%s(%s) - failed to connect to ORPort: %s", name, addrStr, log.ElideError(err)) + return + } + defer orConn.Close() + + if err = copyLoopUDP(orConn, remote); err != nil { + log.Warnf("%s(%s) - closed connection: %s", name, addrStr, log.ElideError(err)) + } else { + log.Infof("%s(%s) - closed connection", name, addrStr) + } + + return +} + +func copyLoopUDP(a net.Conn, b net.Conn) error { + // Note: b is always the pt connection. a is the UDP connection. + errChan := make(chan error, 2) + + var wg sync.WaitGroup + wg.Add(2) + + go func() { + defer wg.Done() + defer b.Close() + defer a.Close() + _, err := io.Copy(b, a) + errChan <- err + }() + go func() { + defer wg.Done() + defer a.Close() + defer b.Close() + _, err := io.Copy(a, b) + errChan <- err + }() + + // Wait for both upstream and downstream to close. Since one side + // terminating closes the other, the second error in the channel will be + // something like EINVAL (though io.Copy() will swallow EOF), so only the + // first error is returned. + wg.Wait() + if len(errChan) > 0 { + return <-errChan + } + + return nil +} -- cgit v1.2.3