From 61e5ee5e9704411df3bb11443ba977824bd746c5 Mon Sep 17 00:00:00 2001
From: Alva Swanson <alvasw@protonmail.com>
Date: Sat, 1 Jun 2024 14:16:12 +0000
Subject: [PATCH] Implement TorController

---
 .../bisq/tor/controller/TorController.java    | 121 ++++++++++++++++++
 1 file changed, 121 insertions(+)
 create mode 100644 network/tor/tor/src/main/java/bisq/tor/controller/TorController.java

diff --git a/network/tor/tor/src/main/java/bisq/tor/controller/TorController.java b/network/tor/tor/src/main/java/bisq/tor/controller/TorController.java
new file mode 100644
index 0000000000..04867ec9af
--- /dev/null
+++ b/network/tor/tor/src/main/java/bisq/tor/controller/TorController.java
@@ -0,0 +1,121 @@
+package bisq.tor.controller;
+
+import bisq.common.observable.Observable;
+import bisq.tor.TorrcClientConfigFactory;
+import bisq.tor.controller.events.events.BootstrapEvent;
+import bisq.tor.controller.events.listener.BootstrapEventListener;
+import bisq.tor.controller.exceptions.TorBootstrapFailedException;
+import bisq.tor.process.NativeTorProcess;
+import lombok.Getter;
+import lombok.extern.slf4j.Slf4j;
+import net.freehaven.tor.control.PasswordDigest;
+
+import java.io.IOException;
+import java.time.Instant;
+import java.time.temporal.ChronoUnit;
+import java.util.Collections;
+import java.util.List;
+import java.util.Optional;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+
+@Slf4j
+public class TorController implements BootstrapEventListener {
+    private final int bootstrapTimeout;
+    private final CountDownLatch isBootstrappedCountdownLatch = new CountDownLatch(1);
+    @Getter
+    private final Observable<BootstrapEvent> bootstrapEvent = new Observable<>();
+
+    private Optional<TorControlProtocol> torControlProtocol = Optional.empty();
+
+    public TorController(int bootstrapTimeout) {
+        this.bootstrapTimeout = bootstrapTimeout;
+    }
+
+    public void initialize(int controlPort, PasswordDigest hashedControlPassword) throws IOException {
+        var torControlProtocol = new TorControlProtocol(controlPort);
+        this.torControlProtocol = Optional.of(torControlProtocol);
+
+        torControlProtocol.initialize();
+        torControlProtocol.authenticate(hashedControlPassword);
+    }
+
+    public void shutdown() {
+        torControlProtocol.ifPresent(torControlProtocol -> {
+            try {
+                torControlProtocol.close();
+            } catch (IOException e) {
+                throw new RuntimeException(e);
+            }
+        });
+    }
+
+    public void bootstrapTor() throws IOException {
+        bindToBisq();
+        subscribeToBootstrapEvents();
+        enableNetworking();
+        waitUntilBootstrapped();
+    }
+
+    @Override
+    public void onBootstrapStatusEvent(BootstrapEvent bootstrapEvent) {
+        log.info("Tor bootstrap event: {}", bootstrapEvent);
+        this.bootstrapEvent.set(bootstrapEvent);
+        if (bootstrapEvent.isDoneEvent()) {
+            isBootstrappedCountdownLatch.countDown();
+        }
+    }
+
+    private void bindToBisq() throws IOException {
+        TorControlProtocol torControlProtocol = getTorControlProtocol();
+        torControlProtocol.takeOwnership();
+        torControlProtocol.resetConf(NativeTorProcess.ARG_OWNER_PID);
+    }
+
+    private void subscribeToBootstrapEvents() throws IOException {
+        TorControlProtocol torControlProtocol = getTorControlProtocol();
+        torControlProtocol.addBootstrapEventListener(this);
+        torControlProtocol.setEvents(List.of("STATUS_CLIENT"));
+    }
+
+    private void enableNetworking() throws IOException {
+        TorControlProtocol torControlProtocol = getTorControlProtocol();
+        torControlProtocol.setConfig(TorrcClientConfigFactory.DISABLE_NETWORK_CONFIG_KEY, "0");
+    }
+
+    private void waitUntilBootstrapped() {
+        try {
+            while (true) {
+                if (torControlProtocol.isEmpty()) {
+                    throw new TorBootstrapFailedException("Tor is not initializing.");
+                }
+
+                boolean isSuccess = isBootstrappedCountdownLatch.await(bootstrapTimeout, TimeUnit.MILLISECONDS);
+
+                if (isSuccess) {
+                    TorControlProtocol torControlProtocol = this.torControlProtocol.get();
+                    torControlProtocol.removeBootstrapEventListener(this);
+                    torControlProtocol.setEvents(Collections.emptyList());
+                    break;
+                } else if (isBootstrapTimeoutTriggered()) {
+                    throw new TorBootstrapFailedException("Tor bootstrap timeout triggered.");
+                }
+            }
+        } catch (InterruptedException e) {
+            throw new TorBootstrapFailedException(e);
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    private boolean isBootstrapTimeoutTriggered() {
+        BootstrapEvent bootstrapEvent = this.bootstrapEvent.get();
+        Instant timestamp = bootstrapEvent.getTimestamp();
+        Instant bootstrapTimeoutAgo = Instant.now().minus(bootstrapTimeout, ChronoUnit.MILLIS);
+        return bootstrapTimeoutAgo.isAfter(timestamp);
+    }
+
+    private TorControlProtocol getTorControlProtocol() {
+        return this.torControlProtocol.orElseThrow();
+    }
+}