Factor out onion address encoder to CryptoComponent

bramble-android/src/main/java/org/briarproject/bramble/plugin/tor/AndroidTorPluginFactory.java

@@ -3,6 +3,7 @@ package org.briarproject.bramble.plugin.tor;
 import android.app.Application;
 
 import org.briarproject.bramble.api.battery.BatteryManager;
+import org.briarproject.bramble.api.crypto.CryptoComponent;
 import org.briarproject.bramble.api.event.EventBus;
 import org.briarproject.bramble.api.lifecycle.IoExecutor;
 import org.briarproject.bramble.api.network.NetworkManager;
@@ -60,6 +61,7 @@ public class AndroidTorPluginFactory implements DuplexPluginFactory {
 	private final File torDirectory;
 	private int torSocksPort;
 	private int torControlPort;
+	private final CryptoComponent crypto;
 
 	@Inject
 	AndroidTorPluginFactory(@IoExecutor Executor ioExecutor,
@@ -77,7 +79,8 @@ public class AndroidTorPluginFactory implements DuplexPluginFactory {
 			Clock clock,
 			@TorDirectory File torDirectory,
 			@TorSocksPort int torSocksPort,
-			@TorControlPort int torControlPort) {
+			@TorControlPort int torControlPort,
+			CryptoComponent crypto) {
 		this.ioExecutor = ioExecutor;
 		this.wakefulIoExecutor = wakefulIoExecutor;
 		this.app = app;
@@ -94,6 +97,7 @@ public class AndroidTorPluginFactory implements DuplexPluginFactory {
 		this.torDirectory = torDirectory;
 		this.torSocksPort = torSocksPort;
 		this.torControlPort = torControlPort;
+		this.crypto = crypto;
 	}
 
 	@Override
@@ -135,7 +139,8 @@ public class AndroidTorPluginFactory implements DuplexPluginFactory {
 
 		Backoff backoff = backoffFactory.createBackoff(MIN_POLLING_INTERVAL,
 				MAX_POLLING_INTERVAL, BACKOFF_BASE);
-		TorRendezvousCrypto torRendezvousCrypto = new TorRendezvousCryptoImpl();
+		TorRendezvousCrypto torRendezvousCrypto =
+				new TorRendezvousCryptoImpl(crypto);
 		AndroidTorPlugin plugin = new AndroidTorPlugin(ioExecutor,
 				wakefulIoExecutor, app, networkManager, locationUtils,
 				torSocketFactory, clock, resourceProvider,

bramble-api/src/main/java/org/briarproject/bramble/api/crypto/CryptoComponent.java

@@ -170,4 +170,11 @@ public interface CryptoComponent {
 	 * length. The line terminator is CRLF.
 	 */
 	String asciiArmour(byte[] b, int lineLength);
+
+	/**
+	 * Encode the onion/hidden service address given its public key. As
+	 * specified here: https://gitweb.torproject.org/torspec.git/tree/rend-spec-v3.txt?id=29245fd5#n2135
+	 */
+	String encodeOnionAddress(byte[] publicKey);
+
 }

bramble-core/src/main/java/org/briarproject/bramble/crypto/CryptoComponentImpl.java

@@ -7,6 +7,7 @@ import net.i2p.crypto.eddsa.KeyPairGenerator;
 import org.bouncycastle.crypto.CryptoException;
 import org.bouncycastle.crypto.Digest;
 import org.bouncycastle.crypto.digests.Blake2bDigest;
+import org.bouncycastle.crypto.digests.SHA3Digest;
 import org.briarproject.bramble.api.crypto.AgreementPrivateKey;
 import org.briarproject.bramble.api.crypto.AgreementPublicKey;
 import org.briarproject.bramble.api.crypto.CryptoComponent;
@@ -21,11 +22,13 @@ import org.briarproject.bramble.api.crypto.SignaturePrivateKey;
 import org.briarproject.bramble.api.crypto.SignaturePublicKey;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.system.SecureRandomProvider;
+import org.briarproject.bramble.util.Base32;
 import org.briarproject.bramble.util.ByteUtils;
 import org.briarproject.bramble.util.StringUtils;
 import org.whispersystems.curve25519.Curve25519;
 import org.whispersystems.curve25519.Curve25519KeyPair;
 
+import java.nio.charset.Charset;
 import java.security.GeneralSecurityException;
 import java.security.NoSuchAlgorithmException;
 import java.security.Provider;
@@ -58,6 +61,8 @@ class CryptoComponentImpl implements CryptoComponent {
 	private static final int PBKDF_SALT_BYTES = 32; // 256 bits
 	private static final byte PBKDF_FORMAT_SCRYPT = 0;
 	private static final byte PBKDF_FORMAT_SCRYPT_STRENGTHENED = 1;
+	private static final byte ONION_HS_PROTOCOL_VERSION = 3;
+	private static final int ONION_CHECKSUM_BYTES = 2;
 
 	private final SecureRandom secureRandom;
 	private final PasswordBasedKdf passwordBasedKdf;
@@ -442,4 +447,21 @@ class CryptoComponentImpl implements CryptoComponent {
 	public String asciiArmour(byte[] b, int lineLength) {
 		return AsciiArmour.wrap(b, lineLength);
 	}
+
+	@Override
+	public String encodeOnionAddress(byte[] publicKey) {
+		Digest digest = new SHA3Digest(256);
+		byte[] label = ".onion checksum".getBytes(Charset.forName("US-ASCII"));
+		digest.update(label, 0, label.length);
+		digest.update(publicKey, 0, publicKey.length);
+		digest.update(ONION_HS_PROTOCOL_VERSION);
+		byte[] checksum = new byte[digest.getDigestSize()];
+		digest.doFinal(checksum, 0);
+		byte[] address = new byte[publicKey.length + ONION_CHECKSUM_BYTES + 1];
+		arraycopy(publicKey, 0, address, 0, publicKey.length);
+		arraycopy(checksum, 0, address, publicKey.length, ONION_CHECKSUM_BYTES);
+		address[address.length - 1] = ONION_HS_PROTOCOL_VERSION;
+		return Base32.encode(address).toLowerCase();
+	}
+
 }

bramble-core/src/main/java/org/briarproject/bramble/plugin/tor/TorRendezvousCryptoImpl.java

@@ -4,39 +4,26 @@ import net.i2p.crypto.eddsa.spec.EdDSANamedCurveSpec;
 import net.i2p.crypto.eddsa.spec.EdDSANamedCurveTable;
 import net.i2p.crypto.eddsa.spec.EdDSAPrivateKeySpec;
 
-import org.bouncycastle.crypto.Digest;
-import org.bouncycastle.crypto.digests.SHA3Digest;
 import org.bouncycastle.util.encoders.Base64;
-import org.briarproject.bramble.util.Base32;
+import org.briarproject.bramble.api.crypto.CryptoComponent;
 
 import java.nio.charset.Charset;
 
-import static java.lang.System.arraycopy;
-
 public class TorRendezvousCryptoImpl implements TorRendezvousCrypto {
 
 	private static final EdDSANamedCurveSpec CURVE_SPEC =
 			EdDSANamedCurveTable.getByName("Ed25519");
 
-	private static final byte HS_PROTOCOL_VERSION = 3;
+	private final CryptoComponent crypto;
-	private static final int CHECKSUM_BYTES = 2;
+
+	TorRendezvousCryptoImpl(CryptoComponent crypto) {
+		this.crypto = crypto;
+	}
 
 	@Override
 	public String getOnionAddress(byte[] seed) {
 		EdDSAPrivateKeySpec spec = new EdDSAPrivateKeySpec(seed, CURVE_SPEC);
-		byte[] publicKey = spec.getA().toByteArray();
+		return crypto.encodeOnionAddress(spec.getA().toByteArray());
-		Digest digest = new SHA3Digest(256);
-		byte[] label = ".onion checksum".getBytes(Charset.forName("US-ASCII"));
-		digest.update(label, 0, label.length);
-		digest.update(publicKey, 0, publicKey.length);
-		digest.update(HS_PROTOCOL_VERSION);
-		byte[] checksum = new byte[digest.getDigestSize()];
-		digest.doFinal(checksum, 0);
-		byte[] address = new byte[publicKey.length + CHECKSUM_BYTES + 1];
-		arraycopy(publicKey, 0, address, 0, publicKey.length);
-		arraycopy(checksum, 0, address, publicKey.length, CHECKSUM_BYTES);
-		address[address.length - 1] = HS_PROTOCOL_VERSION;
-		return Base32.encode(address).toLowerCase();
 	}
 
 	@Override

bramble-java/src/main/java/org/briarproject/bramble/plugin/tor/UnixTorPluginFactory.java

@@ -1,6 +1,7 @@
 package org.briarproject.bramble.plugin.tor;
 
 import org.briarproject.bramble.api.battery.BatteryManager;
+import org.briarproject.bramble.api.crypto.CryptoComponent;
 import org.briarproject.bramble.api.event.EventBus;
 import org.briarproject.bramble.api.lifecycle.IoExecutor;
 import org.briarproject.bramble.api.network.NetworkManager;
@@ -58,6 +59,7 @@ public class UnixTorPluginFactory implements DuplexPluginFactory {
 	private final File torDirectory;
 	private int torSocksPort;
 	private int torControlPort;
+	private final CryptoComponent crypto;
 
 	@Inject
 	UnixTorPluginFactory(@IoExecutor Executor ioExecutor,
@@ -73,7 +75,8 @@ public class UnixTorPluginFactory implements DuplexPluginFactory {
 			Clock clock,
 			@TorDirectory File torDirectory,
 			@TorSocksPort int torSocksPort,
-			@TorControlPort int torControlPort) {
+			@TorControlPort int torControlPort,
+			CryptoComponent crypto) {
 		this.ioExecutor = ioExecutor;
 		this.wakefulIoExecutor = wakefulIoExecutor;
 		this.networkManager = networkManager;
@@ -88,6 +91,7 @@ public class UnixTorPluginFactory implements DuplexPluginFactory {
 		this.torDirectory = torDirectory;
 		this.torSocksPort = torSocksPort;
 		this.torControlPort = torControlPort;
+		this.crypto = crypto;
 	}
 
 	@Override
@@ -128,7 +132,8 @@ public class UnixTorPluginFactory implements DuplexPluginFactory {
 
 		Backoff backoff = backoffFactory.createBackoff(MIN_POLLING_INTERVAL,
 				MAX_POLLING_INTERVAL, BACKOFF_BASE);
-		TorRendezvousCrypto torRendezvousCrypto = new TorRendezvousCryptoImpl();
+		TorRendezvousCrypto torRendezvousCrypto =
+				new TorRendezvousCryptoImpl(crypto);
 		UnixTorPlugin plugin = new UnixTorPlugin(ioExecutor, wakefulIoExecutor,
 				networkManager, locationUtils, torSocketFactory, clock,
 				resourceProvider, circumventionProvider, batteryManager,

bramble-java/src/test/java/org/briarproject/bramble/plugin/tor/BridgeTest.java

@@ -2,6 +2,7 @@ package org.briarproject.bramble.plugin.tor;
 
 import org.briarproject.bramble.BrambleCoreIntegrationTestEagerSingletons;
 import org.briarproject.bramble.api.battery.BatteryManager;
+import org.briarproject.bramble.api.crypto.CryptoComponent;
 import org.briarproject.bramble.api.event.EventBus;
 import org.briarproject.bramble.api.lifecycle.IoExecutor;
 import org.briarproject.bramble.api.network.NetworkManager;
@@ -88,6 +89,8 @@ public class BridgeTest extends BrambleTestCase {
 	BackoffFactory backoffFactory;
 	@Inject
 	Clock clock;
+	@Inject
+	CryptoComponent crypto;
 
 	private final File torDir = getTestDirectory();
 	private final String bridge;
@@ -142,7 +145,7 @@ public class BridgeTest extends BrambleTestCase {
 				networkManager, locationUtils, eventBus, torSocketFactory,
 				backoffFactory, resourceProvider, bridgeProvider,
 				batteryManager, clock, torDir, DEFAULT_SOCKS_PORT,
-				DEFAULT_CONTROL_PORT);
+				DEFAULT_CONTROL_PORT, crypto);
 	}
 
 	@After