From c4221c3c3aa074b1a040a6418ffdbe0ebeaa0903 Mon Sep 17 00:00:00 2001
From: Adrian-Stefan Mares <a.mares@student.tue.nl>
Date: Sun, 20 Jun 2021 11:16:03 +0200
Subject: [PATCH] config+lnd: Update Tor configuration for hybrid node mode

---
 config.go    |  9 +++++----
 lncfg/tor.go |  1 +
 lnd.go       | 20 +++++++++++++++++---
 3 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/config.go b/config.go
index d795feed0..d07e6c22b 100644
--- a/config.go
+++ b/config.go
@@ -906,9 +906,10 @@ func ValidateConfig(cfg Config, usageMessage string,
 	// our real information.
 	if cfg.Tor.Active {
 		cfg.net = &tor.ProxyNet{
-			SOCKS:           cfg.Tor.SOCKS,
-			DNS:             cfg.Tor.DNS,
-			StreamIsolation: cfg.Tor.StreamIsolation,
+			SOCKS:             cfg.Tor.SOCKS,
+			DNS:               cfg.Tor.DNS,
+			StreamIsolation:   cfg.Tor.StreamIsolation,
+			DirectConnections: cfg.Tor.DirectConnections,
 		}
 	}
 
@@ -1316,7 +1317,7 @@ func ValidateConfig(cfg Config, usageMessage string,
 	// connections.
 	if len(cfg.RawListeners) == 0 {
 		addr := fmt.Sprintf(":%d", defaultPeerPort)
-		if cfg.Tor.Active {
+		if cfg.Tor.Active && !cfg.Tor.DirectConnections {
 			addr = fmt.Sprintf("localhost:%d", defaultPeerPort)
 		}
 		cfg.RawListeners = append(cfg.RawListeners, addr)
diff --git a/lncfg/tor.go b/lncfg/tor.go
index e7070c38c..8051e399f 100644
--- a/lncfg/tor.go
+++ b/lncfg/tor.go
@@ -6,6 +6,7 @@ type Tor struct {
 	SOCKS             string `long:"socks" description:"The host:port that Tor's exposed SOCKS5 proxy is listening on"`
 	DNS               string `long:"dns" description:"The DNS server as host:port that Tor will use for SRV queries - NOTE must have TCP resolution enabled"`
 	StreamIsolation   bool   `long:"streamisolation" description:"Enable Tor stream isolation by randomizing user credentials for each connection."`
+	DirectConnections bool   `long:"directconnections" description:"Allow the node to establish direct connections to services not running behind Tor."`
 	Control           string `long:"control" description:"The host:port that Tor is listening on for Tor control connections"`
 	TargetIPAddress   string `long:"targetipaddress" description:"IP address that Tor should use as the target of the hidden service"`
 	Password          string `long:"password" description:"The password used to arrive at the HashedControlPassword for the control port. If provided, the HASHEDPASSWORD authentication method will be used instead of the SAFECOOKIE one."`
diff --git a/lnd.go b/lnd.go
index bd0f2839d..a00dc9ca1 100644
--- a/lnd.go
+++ b/lnd.go
@@ -8,6 +8,7 @@ import (
 	"bytes"
 	"context"
 	"crypto/tls"
+	"errors"
 	"fmt"
 	"io/ioutil"
 	"net"
@@ -168,6 +169,10 @@ type ListenerCfg struct {
 	ExternalRestRegistrar RestRegistrar
 }
 
+var errStreamIsolationWithDirectConnections = errors.New(
+	"direct connections cannot be used while stream isolation is enabled",
+)
+
 // Main is the true entry point for lnd. It accepts a fully populated and
 // validated main configuration struct and an optional listener config struct.
 // This function starts all main system components then blocks until a signal
@@ -752,10 +757,19 @@ func Main(cfg *Config, lisCfg ListenerCfg, interceptor signal.Interceptor) error
 		return err
 	}
 
+	if cfg.Tor.StreamIsolation && cfg.Tor.DirectConnections {
+		return errStreamIsolationWithDirectConnections
+	}
+
 	if cfg.Tor.Active {
-		srvrLog.Infof("Proxying all network traffic via Tor "+
-			"(stream_isolation=%v)! NOTE: Ensure the backend node "+
-			"is proxying over Tor as well", cfg.Tor.StreamIsolation)
+		if cfg.Tor.DirectConnections {
+			srvrLog.Info("Onion services are accessible via Tor! NOTE: " +
+				"Traffic to clearnet services is not routed via Tor.")
+		} else {
+			srvrLog.Infof("Proxying all network traffic via Tor "+
+				"(stream_isolation=%v)! NOTE: Ensure the backend node "+
+				"is proxying over Tor as well", cfg.Tor.StreamIsolation)
+		}
 	}
 
 	// If the watchtower client should be active, open the client database.