TorIdentity: Add onion address encoding from key

network/tor/tor/src/main/java/bisq/tor/TorIdentity.java

@@ -19,40 +19,61 @@
 
 import lombok.Getter;
 import lombok.ToString;
+import org.bouncycastle.crypto.digests.SHA3Digest;
 import org.bouncycastle.crypto.digests.SHA512Digest;
 import org.bouncycastle.math.ec.rfc8032.Ed25519;
+import org.bouncycastle.util.encoders.Base32;
 
+import java.nio.ByteBuffer;
 import java.security.SecureRandom;
 
 @Getter
 @ToString
 public class TorIdentity {
 
     @ToString.Exclude
-    private final String privateKey;
+    private final byte[] privateKey;
     private final int port;
 
-    public TorIdentity(String privateKey, int port) {
+    public TorIdentity(byte[] privateKey, int port) {
         this.privateKey = privateKey;
         this.port = port;
     }
 
     public static TorIdentity generate(int port) {
-        // Key Format definition:
-        // https://gitlab.torproject.org/tpo/core/torspec/-/blob/main/control-spec.txt
-
         byte[] privateKey = new byte[32];
         Ed25519.generatePrivateKey(new SecureRandom(), privateKey);
+        return new TorIdentity(privateKey, port);
+    }
+
+    public String getTorOnionKey() {
+        // Key Format definition:
+        // https://gitlab.torproject.org/tpo/core/torspec/-/blob/main/control-spec.txt
 
         byte[] secretScalar = generateSecretScalar(privateKey);
         String base64EncodedSecretScalar = java.util.Base64.getEncoder()
                 .encodeToString(secretScalar);
 
-        String torOnionKey = "-----BEGIN OPENSSH PRIVATE KEY-----\n" +
+        return "-----BEGIN OPENSSH PRIVATE KEY-----\n" +
                 base64EncodedSecretScalar + "\n" +
                 "-----END OPENSSH PRIVATE KEY-----\n";
+    }
+
+    public String getOnionAddress() {
+        byte[] publicKey = new byte[32];
+        Ed25519.generatePublicKey(privateKey, 0, publicKey, 0);
 
-        return new TorIdentity(torOnionKey, port);
+        byte[] checksumForAddress = computeOnionAddressChecksum(publicKey);
+
+        ByteBuffer byteBuffer = ByteBuffer.allocate(32 + 2 + 1);
+        byteBuffer.put(publicKey); // 32 bytes
+        byteBuffer.put(checksumForAddress); // 2 bytes
+        byteBuffer.put((byte) 3); // 1 byte
+
+        byte[] byteArray = byteBuffer.array();
+        String base32String = Base32.toBase32String(byteArray);
+
+        return base32String.toLowerCase() + ".onion";
     }
 
     private static byte[] generateSecretScalar(byte[] privateKey) {
@@ -70,4 +91,24 @@ private static byte[] generateSecretScalar(byte[] privateKey) {
 
         return secretScalar;
     }
+
+    private byte[] computeOnionAddressChecksum(byte[] publicKey) {
+        ByteBuffer byteBuffer = ByteBuffer.allocate(15 + 32 + 1);
+        byteBuffer.put(".onion checksum".getBytes()); // 15 bytes
+        byteBuffer.put(publicKey); // 32 bytes
+        byteBuffer.put((byte) 3); // 1 byte
+
+        byte[] byteArray = byteBuffer.array();
+
+        SHA3Digest sha3_256Digest = new SHA3Digest();
+        sha3_256Digest.update(byteArray, 0, byteArray.length);
+
+        byte[] hashedByteArray = new byte[64];
+        sha3_256Digest.doFinal(hashedByteArray, 0);
+
+        return new byte[]{
+                hashedByteArray[0],
+                hashedByteArray[1]
+        };
+    }
 }

network/tor/tor/src/main/java/bisq/tor/onionservice/OnionServicePublishService.java

@@ -76,7 +76,7 @@ public synchronized CompletableFuture<OnionAddress> publish(String nodeId, int o
 
     public synchronized CompletableFuture<Void> publish(TorIdentity torIdentity, int localPort) {
         try {
-            Optional<String> privateKey = Optional.of(torIdentity.getPrivateKey());
+            Optional<String> privateKey = Optional.of(torIdentity.getTorOnionKey());
             nativeTorController.createHiddenService(torIdentity.getPort(), localPort, privateKey);
             return CompletableFuture.completedFuture(null);