tlsmux

README

tlsmux

Go package providing an implementation of a net.Conn multiplexer based on the TLS SNI (Server Name Indication) sent by a client.

Installation

Install using go get github.com/kevinpollet/tlsmux.

Usage

Mux

The Mux struct allows registering handlers which will be called when the muxer serve a net.Conn with a matching server name.

mux := tlsmux.Mux{}

l, err := net.Listen("tcp", "127.0.0.1:8080")
if err != nil {
    log.Fatal(err)
}

if err := mux.Serve(l); err != nil {
    log.Fatal(err)
}

Handler

The Handler interface is used to handle an incoming net.Conn without decrypting the underlying TLS communication (Pass Through). Implementations are responsible for closing the connection.

The HandlerFunc type is an adapter to allow the use of ordinary functions as a Handler.

mux.Handle("server.name", tlsmux.HandlerFunc(func(conn net.Conn) error {
    defer conn.Close()

    // Handle the encrypted TLS connection.
}))

TLSHandler

The TLSHandler struct is a Handler implementation allowing to terminate the TLS connection with the configured tls.Config. Thus, the net.Conn parameter of a TLSHandler if of type tls.Conn.
Implementations are responsible for closing the connection.

The TLSHandlerFunc type is an adapter to allow the use of ordinary functions as a TLSHandler.

cfg := &tls.Config{
    MinVersion: tls.VersionTLS13,
    Certificates: []tls.Certificate{cert},
}

mux.Handle("foo.localhost", tlsmux.TLSHandlerFunc(cfg, func(conn net.Conn) error {
    defer conn.Close()

    // Handle the decrypted TLS connection.
}))

ProxyHandler

The ProxyHandler struct is a Handler implementation forwarding the connection bytes to the configured Address. The ProxyHandlerFunc is an adapter allowing the use of a ProxyHandler as a HandlerFunc.

// Forward the encrypted connection bytes.
mux.Handle("foo.localhost", tlsmux.ProxyHandler{Addr: "127.0.0.1:443"})

// Forward the decrypted connection bytes.
mux.Handle("foo.localhost", tlsmux.TLSHandlerFunc(tlsConfig, tlsmux.ProxyHandlerFunc("127.0.0.1:80"))

License

MIT

Documentation

Index

• func ClientHelloServerName(conn net.Conn) (string, []byte)
• type Handler
• type HandlerFunc
  • func ProxyHandlerFunc(addr string) HandlerFunc
  • func (h HandlerFunc) ServeConn(conn net.Conn) error
• type Mux
  • func (m *Mux) Handle(serverName string, handler Handler)
  • func (m *Mux) Serve(l net.Listener) error
  • func (m *Mux) ServeConn(c net.Conn) error
• type ProxyHandler
  • func (p ProxyHandler) ServeConn(conn net.Conn) error
• type TLSHandler
  • func TLSHandlerFunc(config *tls.Config, handler HandlerFunc) TLSHandler
  • func (h TLSHandler) ServeConn(conn net.Conn) error

Functions

func ClientHelloServerName

func ClientHelloServerName(conn net.Conn) (string, []byte)

ClientHelloServerName reads the TLS server name from the given net.Conn and returns it with the peeked bytes.

Types

type Handler

type Handler interface {
	ServeConn(net.Conn) error
}

Handler is in charge of handling as connection.

type HandlerFunc

type HandlerFunc func(net.Conn) error

HandlerFunc is an adapter to allow the use of ordinary functions as a Handler.

func ProxyHandlerFunc

func ProxyHandlerFunc(addr string) HandlerFunc

ProxyHandlerFunc is an adapter to allow the use of a ProxyHandler as a HandlerFunc.

func (HandlerFunc) ServeConn

func (h HandlerFunc) ServeConn(conn net.Conn) error

type Mux

type Mux struct {
	// contains filtered or unexported fields
}

Mux is a TCP connection multiplexer which reads the TLS server name indication to route the connection to the matching Handler.

func (*Mux) Handle

func (m *Mux) Handle(serverName string, handler Handler)

Handle registers a Handler for the given server name.

func (*Mux) Serve

func (m *Mux) Serve(l net.Listener) error

Serve accepts incoming connections on the given listener and starts a go routine to serve each connection. TODO handle errors.

func (*Mux) ServeConn

func (m *Mux) ServeConn(c net.Conn) error

ServeConn reads the TLS server name indication and forwards the net.Conn to the matching Handler. Handler implementations are responsible for closing the connection. TODO: handle panics TODO: client hello timeout.

type ProxyHandler

type ProxyHandler struct {
	Addr string
}

ProxyHandler is a Handler implementation forwarding the connection bytes to the configured Addr.

func (ProxyHandler) ServeConn

func (p ProxyHandler) ServeConn(conn net.Conn) error

type TLSHandler

type TLSHandler struct {
	Handler

	Config *tls.Config
}

TLSHandler is a Handler implementation handling TLS connection by using the configured tls.Config.

func TLSHandlerFunc

func TLSHandlerFunc(config *tls.Config, handler HandlerFunc) TLSHandler

TLSHandlerFunc is an adapter to allow the use of a function as a TLSHandler.

func (TLSHandler) ServeConn

func (h TLSHandler) ServeConn(conn net.Conn) error