make local port selection deterministic and detach from the control port to improve performane

.gitignore

@@ -3,3 +3,4 @@
 examples/basic/basic
 examples/listener/listener
 examples/dialer/dialer
+.idea/*

cmd_onion.go

@@ -111,7 +111,7 @@ func (c *Conn) NewOnion(config *NewOnionConfig) (*OnionInfo, error) {
 	}
 	request := fmt.Sprintf("ADD_ONION %s:%s%s%s", hsKeyType, hsKeyStr, portStr, flagsStr)
 	resp, err := c.Request(request)
-	if err != nil {
+	if err != nil && fmt.Sprintf("%v", err) != "550 Unspecified Tor error: Onion address collision" {
 		return nil, err
 	}
 
@@ -153,11 +153,6 @@ func (c *Conn) NewOnion(config *NewOnionConfig) (*OnionInfo, error) {
 			}
 		}
 	}
-	if serviceID == "" {
-		// This should *NEVER* happen, since the command succeded, and the spec
-		// guarantees that this will always be present.
-		return nil, newProtocolError("failed to determine service ID")
-	}
 
 	oi := new(OnionInfo)
 	oi.RawResponse = resp

listener.go

@@ -8,11 +8,15 @@
 package bulb
 
 import (
-	"crypto"
+	goodrand "crypto/rand"
 	"fmt"
-	"net"
+		"net"
 	"strconv"
-)
+	"golang.org/x/crypto/sha3"
+		badrand "math/rand"
+	"encoding/binary"
+			"crypto"
+	)
 
 type onionAddr struct {
 	info *OnionInfo
@@ -55,7 +59,13 @@ func (l *onionListener) Addr() net.Addr {
 // All of virtual ports specified in vports will be mapped to the port to which
 // the underlying TCP listener binded. PortSpecs in config will be ignored since
 // there is only one mapping for a vports set is possible.
+
+// [DEPRECATED] generate a random port to listen on (this is for backwards compatibility)
 func (c *Conn) NewListener(config *NewOnionConfig, vports ...uint16) (net.Listener, error) {
+	return c.RecoverListener(config, "", vports...)
+}
+
+func (c *Conn) RecoverListener(config *NewOnionConfig, onion string, vports ...uint16) (net.Listener, error) {
 	var cfg NewOnionConfig
 	if config == nil {
 		cfg = NewOnionConfig{
@@ -65,7 +75,20 @@ func (c *Conn) NewListener(config *NewOnionConfig, vports ...uint16) (net.Listen
 		cfg = *config
 	}
 
-	const loopbackAddr = "127.0.0.1:0"
+	var port int
+	if onion == "" { // generate a random port for ephemeral programs
+		seedbytes := make([]byte, 2)
+		goodrand.Read(seedbytes)
+		port = int(binary.LittleEndian.Uint16(seedbytes))
+		if port < 1024 { // because why not ^ea
+			port = 1024 + int(seedbytes[0]) + int(seedbytes[1])
+		}
+	} else { // generate a deterministic port for resumptive programs
+		seedbytes := sha3.New224().Sum([]byte(onion))
+		seed := badrand.NewSource(int64(binary.LittleEndian.Uint64(seedbytes[:8])))
+		port = badrand.New(seed).Intn(64511) + 1024
+	}
+	var loopbackAddr = "127.0.0.1:" + strconv.Itoa(port)
 
 	// Listen on the loopback interface.
 	tcpListener, err := net.Listen("tcp4", loopbackAddr)
@@ -79,7 +102,7 @@ func (c *Conn) NewListener(config *NewOnionConfig, vports ...uint16) (net.Listen
 	}
 
 	if len(vports) < 1 {
-		return nil, newProtocolError("no virual ports specified")
+		return nil, newProtocolError("no virtual ports specified")
 	}
 	targetPortStr := strconv.FormatUint((uint64)(tAddr.Port), 10)
 	var portSpecs []OnionPortSpec