telebit/mplexer/routemux.go

177 lines
4.6 KiB
Go

package telebit
import (
"errors"
"fmt"
"net"
"strconv"
"strings"
"time"
)
// A RouteMux is a net.Conn multiplexer.
//
// It matches the port, domain, or connection type of a connection
// and selects the matching handler.
type RouteMux struct {
defaultTimeout time.Duration
routes []meta
}
// ErrNotHandled is returned when the next middleware in the stack should take over
var ErrNotHandled = errors.New("connection not handled")
type meta struct {
addr string
handler Handler
terminate bool
comment string
}
// NewRouteMux allocates and returns a new RouteMux.
func NewRouteMux() *RouteMux {
mux := &RouteMux{
defaultTimeout: 45 * time.Second,
}
return mux
}
// Serve dispatches the connection to the handler whose selectors matches the attributes.
func (m *RouteMux) Serve(client net.Conn) error {
fmt.Println("\n\n[debug] mux.Serve(client)")
var wconn *ConnWrap
switch conn := client.(type) {
case *ConnWrap:
wconn = conn
default:
wconn = &ConnWrap{Conn: client}
}
var servername string
var port string
// TODO go back to Servername on conn, but with SNI
//servername := wconn.Servername()
fam := wconn.LocalAddr().Network()
if "tun" == fam {
switch laddr := wconn.LocalAddr().(type) {
case *Addr:
servername = laddr.Hostname()
port = ":" + strconv.Itoa(laddr.Port())
connServername := wconn.CheckServername()
if "" == connServername {
wconn.SetServername(servername)
} else {
fmt.Printf("Has servername: current=%s new=%s\n", connServername, servername)
wconn.SetServername(servername)
//panic(errors.New("Can't SetServername() over existing servername"))
}
default:
panic("impossible type switch: Addr is 'tun' but didn't match")
}
} else {
// TODO make an AddrWrap to do this switch
addr := wconn.LocalAddr().String()
parts := strings.Split(addr, ":")
port = ":" + parts[len(parts)-1]
servername = strings.Join(parts[:len(parts)-1], ":")
}
fmt.Println("Addr:", fam, servername, port)
for _, meta := range m.routes {
// TODO '*.example.com'
if meta.terminate {
servername = wconn.Servername()
}
fmt.Println("\nMeta:", meta.comment, "meta.addr="+meta.addr, "servername="+servername)
if servername == meta.addr || "*" == meta.addr || port == meta.addr {
//fmt.Println("[debug] test of route:", meta)
// Only keep trying handlers if ErrNotHandled was returned
if err := meta.handler.Serve(wconn); ErrNotHandled != err {
return err
}
}
}
fmt.Println("No match found for", wconn.Scheme(), wconn.Servername())
return client.Close()
// TODO Chi-style route handling
/*
routes := m.routes
next := func() error {
if 0 == len(routes) {
fmt.Println("No match found for", wconn.Scheme(), wconn.Servername())
return client.Close()
}
route := routes[0]
routes := routes[1:]
handled := false
handler := meta.handler(func () {
if !handled {
handled = true
next()
}
})
return handler.Serve(client)
}
return next()
*/
}
// ForwardTCP creates and returns a connection to a local handler target.
func (m *RouteMux) ForwardTCP(servername string, target string, timeout time.Duration, comment ...string) error {
// TODO check servername
m.routes = append(m.routes, meta{
addr: servername,
terminate: false,
handler: NewForwarder(target, timeout),
comment: append(comment, "")[0],
})
return nil
}
// HandleTCP creates and returns a connection to a local handler target.
func (m *RouteMux) HandleTCP(servername string, handler Handler, comment ...string) error {
// TODO check servername
m.routes = append(m.routes, meta{
addr: servername,
terminate: false,
handler: handler,
comment: append(comment, "")[0],
})
return nil
}
// HandleTLS creates and returns a connection to a local handler target.
func (m *RouteMux) HandleTLS(servername string, acme *ACME, next Handler, comment ...string) error {
// TODO check servername
m.routes = append(m.routes, meta{
addr: servername,
terminate: true,
handler: HandlerFunc(func(client net.Conn) error {
var wconn *ConnWrap
switch conn := client.(type) {
case *ConnWrap:
wconn = conn
default:
panic("HandleTLS is special in that it must receive &ConnWrap{ Conn: conn }")
}
if !wconn.isEncrypted() {
fmt.Println("[debug] HandleTLS: conn is not encrypted")
// TODO handle underlying Peek() timeout error
return ErrNotHandled
}
fmt.Println("[debug] HandleTLS: decrypted connection, recursing")
//NewTerminator(acme, handler)(client)
//return handler.Serve(client)
return next.Serve(TerminateTLS(wconn, acme))
}),
comment: append(comment, "")[0],
})
return nil
}