Util: Hook in ByteArrayStream

Set accurate lengths for zero-copy

apps/ministreaming/java/src/net/i2p/client/streaming/I2PSocketManagerFactory.java

@@ -1,7 +1,6 @@
 package net.i2p.client.streaming;
 
 import java.io.ByteArrayInputStream;
-import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.lang.reflect.Constructor;
@@ -15,6 +14,7 @@ import net.i2p.client.I2PClientFactory;
 import net.i2p.client.I2PSession;
 import net.i2p.client.I2PSessionException;
 import net.i2p.crypto.SigType;
+import net.i2p.util.ByteArrayStream;
 import net.i2p.util.Log;
 
 /**
@@ -171,10 +171,10 @@ public class I2PSocketManagerFactory {
     public static I2PSocketManager createManager(String i2cpHost, int i2cpPort, Properties opts,
                     IncomingConnectionFilter filter) {
         I2PClient client = I2PClientFactory.createClient();
-        ByteArrayOutputStream keyStream = new ByteArrayOutputStream(1024);
+        ByteArrayStream keyStream = new ByteArrayStream(1024);
         try {
             client.createDestination(keyStream, getSigType(opts));
-            ByteArrayInputStream in = new ByteArrayInputStream(keyStream.toByteArray());
+            ByteArrayInputStream in = keyStream.asInputStream();
             return createManager(in, i2cpHost, i2cpPort, opts, filter);
         } catch (IOException ioe) {
             getLog().error("Error creating the destination for socket manager", ioe);
@@ -359,7 +359,7 @@ public class I2PSocketManagerFactory {
                                     throws I2PSessionException {
         if (myPrivateKeyStream == null) {
             I2PClient client = I2PClientFactory.createClient();
-            ByteArrayOutputStream keyStream = new ByteArrayOutputStream(1024);
+            ByteArrayStream keyStream = new ByteArrayStream(1024);
             try {
                 client.createDestination(keyStream, getSigType(opts));
             } catch (I2PException e) {
@@ -367,7 +367,7 @@ public class I2PSocketManagerFactory {
             } catch (IOException e) {
                 throw new I2PSessionException("Error creating keys", e);
             }
-            myPrivateKeyStream = new ByteArrayInputStream(keyStream.toByteArray());
+            myPrivateKeyStream = keyStream.asInputStream();
         }
         return createManager(myPrivateKeyStream, i2cpHost, i2cpPort, opts, false, filter);
     }

apps/streaming/java/src/net/i2p/client/streaming/impl/I2PSocketManagerFull.java

@@ -1,7 +1,5 @@
 package net.i2p.client.streaming.impl;
 
-import java.io.ByteArrayInputStream;
-import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.net.ConnectException;
@@ -38,6 +36,7 @@ import net.i2p.data.Hash;
 import net.i2p.data.PrivateKey;
 import net.i2p.data.PublicKey;
 import net.i2p.data.SimpleDataStructure;
+import net.i2p.util.ByteArrayStream;
 import net.i2p.util.ConvertToHash;
 import net.i2p.util.ConcurrentHashSet;
 import net.i2p.util.Log;
@@ -275,7 +274,7 @@ public class I2PSocketManagerFull implements I2PSocketManager {
             // We don't actually need the same pubkey in the dest, just in the LS.
             // The dest one is unused. But this is how we find the LS keys
             // to reuse in RequestLeaseSetMessageHandler.
-            ByteArrayOutputStream keyStream = new ByteArrayOutputStream(1024);
+            ByteArrayStream keyStream = new ByteArrayStream(1024);
             try {
                 SigType type = getSigType(opts);
                 if (type != SigType.DSA_SHA1) {
@@ -299,7 +298,7 @@ public class I2PSocketManagerFull implements I2PSocketManager {
             } catch (RuntimeException e) {
                 throw new I2PSessionException("Error creating keys", e);
             }
-            privateKeyStream = new ByteArrayInputStream(keyStream.toByteArray());
+            privateKeyStream = keyStream.asInputStream();
         }
         I2PSession rv = _session.addSubsession(privateKeyStream, opts);
         boolean added = _subsessions.add(rv);

core/java/src/net/i2p/crypto/SelfSignedGenerator.java

@@ -40,6 +40,7 @@ import net.i2p.data.SigningPrivateKey;
 import net.i2p.data.SigningPublicKey;
 import net.i2p.data.SimpleDataStructure;
 import net.i2p.util.Addresses;
+import net.i2p.util.ByteArrayStream;
 import net.i2p.util.HexDump;
 import net.i2p.util.RandomSource;
 import net.i2p.util.SecureFileOutputStream;
@@ -904,11 +905,11 @@ public final class SelfSignedGenerator {
      *  @throws IllegalArgumentException
      */
     private static byte[] getEncodedOIDSeq(String oid) {
-        ByteArrayOutputStream baos = new ByteArrayOutputStream(16);
+        byte[] b = getEncodedOID(oid);
+        ByteArrayStream baos = new ByteArrayStream(4 + b.length);
         baos.write(0x30);
         // len to be filled in later
         baos.write(0);
-        byte[] b = getEncodedOID(oid);
         baos.write(b, 0, b.length);
         // NULL
         baos.write(0x05);

core/java/src/net/i2p/data/EncryptedLeaseSet.java

@@ -19,6 +19,7 @@ import net.i2p.crypto.KeyPair;
 import net.i2p.crypto.SHA256Generator;
 import net.i2p.crypto.SigType;
 import net.i2p.crypto.x25519.X25519DH;
+import net.i2p.util.ByteArrayStream;
 import net.i2p.util.Clock;
 import net.i2p.util.Log;
 
@@ -853,7 +854,7 @@ public class EncryptedLeaseSet extends LeaseSet2 {
         _flags = saveFlags;
         SigningPrivateKey bkey = Blinding.blind(key, _alpha);
         int len = size();
-        ByteArrayOutputStream out = new ByteArrayOutputStream(1 + len);
+        ByteArrayStream out = new ByteArrayStream(1 + len);
         try {
             // unlike LS1, sig covers type
             out.write(getType());

core/java/src/net/i2p/data/KeysAndCert.java

@@ -9,7 +9,6 @@ package net.i2p.data;
  *
  */
 
-import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
@@ -18,6 +17,7 @@ import java.util.Arrays;
 import net.i2p.crypto.EncType;
 import net.i2p.crypto.SHA256Generator;
 import net.i2p.crypto.SigType;
+import net.i2p.util.ByteArrayStream;
 
 /**
  * KeysAndCert has a public key, a signing key, and a certificate.
@@ -239,7 +239,9 @@ public class KeysAndCert extends DataStructureImpl {
             return __calculatedHash;
         byte identBytes[];
         try {
-            ByteArrayOutputStream baos = new ByteArrayOutputStream(400);
+            if (_certificate == null)
+                throw new IllegalStateException("KAC hash error");
+            ByteArrayStream baos = new ByteArrayStream(384 + _certificate.size());
             writeBytes(baos);
             identBytes = baos.toByteArray();
         } catch (IOException ioe) {

core/java/src/net/i2p/data/LeaseSet.java

@@ -10,7 +10,6 @@ package net.i2p.data;
  */
 
 import java.io.ByteArrayInputStream;
-import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
@@ -22,6 +21,7 @@ import net.i2p.I2PAppContext;
 import net.i2p.crypto.DSAEngine;
 import net.i2p.crypto.EncType;
 import net.i2p.crypto.SigType;
+import net.i2p.util.ByteArrayStream;
 import net.i2p.util.Clock;
 import net.i2p.util.Log;
 import net.i2p.util.RandomSource;
@@ -335,7 +335,7 @@ public class LeaseSet extends DatabaseEntry {
         if ((_destination == null) || (_encryptionKey == null) || (_signingKey == null))
             return null;
         int len = size();
-        ByteArrayOutputStream out = new ByteArrayOutputStream(len);
+        ByteArrayStream out = new ByteArrayStream(len);
         try {
             _destination.writeBytes(out);
             _encryptionKey.writeBytes(out);
@@ -497,7 +497,7 @@ public class LeaseSet extends DatabaseEntry {
         if (size < 1 || size > MAX_LEASES-1)
             throw new IllegalArgumentException("Bad number of leases for encryption");
         int datalen = ((DATA_LEN * size / 16) + 1) * 16;
-        ByteArrayOutputStream baos = new ByteArrayOutputStream(datalen);
+        ByteArrayStream baos = new ByteArrayStream(datalen);
         for (int i = 0; i < size; i++) {
             _leases.get(i).getGateway().writeBytes(baos);
             _leases.get(i).getTunnelId().writeBytes(baos);
@@ -545,7 +545,7 @@ public class LeaseSet extends DatabaseEntry {
             throw new DataFormatException("Bad number of leases decrypting " + _destination.toBase32() +
                                           " - is this destination encrypted?");
         int datalen = DATA_LEN * size;
-        ByteArrayOutputStream baos = new ByteArrayOutputStream(datalen);
+        ByteArrayStream baos = new ByteArrayStream(datalen);
         for (int i = 0; i < size; i++) {
             _leases.get(i).getGateway().writeBytes(baos);
             _leases.get(i).getTunnelId().writeBytes(baos);

core/java/src/net/i2p/data/LeaseSet2.java

@@ -1,6 +1,5 @@
 package net.i2p.data;
 
-import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
@@ -16,6 +15,7 @@ import net.i2p.crypto.DSAEngine;
 import net.i2p.crypto.EncType;
 import net.i2p.crypto.SigAlgo;
 import net.i2p.crypto.SigType;
+import net.i2p.util.ByteArrayStream;
 import net.i2p.util.Clock;
 import net.i2p.util.Log;
 import net.i2p.util.OrderedProperties;
@@ -289,7 +289,7 @@ public class LeaseSet2 extends LeaseSet {
      *  @return null on error
      */
     public static Signature offlineSign(long expires, SigningPublicKey transientSPK, SigningPrivateKey priv) {
-        ByteArrayOutputStream baos = new ByteArrayOutputStream(128);
+        ByteArrayStream baos = new ByteArrayStream(4 + 2 + transientSPK.length());
         try {
             DataHelper.writeLong(baos, 4, expires / 1000);
             DataHelper.writeLong(baos, 2, transientSPK.getType().getCode());
@@ -314,7 +314,7 @@ public class LeaseSet2 extends LeaseSet {
         I2PAppContext ctx = I2PAppContext.getGlobalContext();
         if (_transientExpires < ctx.clock().now())
             return false;
-        ByteArrayOutputStream baos = new ByteArrayOutputStream(6 + _transientSigningPublicKey.length());
+        ByteArrayStream baos = new ByteArrayStream(4 + 2 + _transientSigningPublicKey.length());
         try {
             DataHelper.writeLong(baos, 4, _transientExpires / 1000);
             DataHelper.writeLong(baos, 2, _transientSigningPublicKey.getType().getCode());
@@ -387,7 +387,7 @@ public class LeaseSet2 extends LeaseSet {
         if (_destination == null)
             return null;
         int len = size();
-        ByteArrayOutputStream out = new ByteArrayOutputStream(len);
+        ByteArrayStream out = new ByteArrayStream(len);
         try {
             writeBytesWithoutSig(out);
         } catch (IOException ioe) {
@@ -605,7 +605,7 @@ public class LeaseSet2 extends LeaseSet {
         if (key == null)
             throw new DataFormatException("No signing key");
         int len = size();
-        ByteArrayOutputStream out = new ByteArrayOutputStream(1 + len);
+        ByteArrayStream out = new ByteArrayStream(1 + len);
         try {
             // unlike LS1, sig covers type
             out.write(getType());
@@ -647,7 +647,7 @@ public class LeaseSet2 extends LeaseSet {
             spk = getSigningPublicKey();
         }
         int len = size();
-        ByteArrayOutputStream out = new ByteArrayOutputStream(1 + len);
+        ByteArrayStream out = new ByteArrayStream(1 + len);
         try {
             // unlike LS1, sig covers type
             out.write(getType());

core/java/src/net/i2p/data/i2cp/BandwidthLimitsMessage.java

@@ -5,12 +5,12 @@ package net.i2p.data.i2cp;
  *
  */
 
-import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 
 import net.i2p.data.DataFormatException;
 import net.i2p.data.DataHelper;
+import net.i2p.util.ByteArrayStream;
 
 /**
  * Tell the other side the limits
@@ -63,7 +63,7 @@ public class BandwidthLimitsMessage extends I2CPMessageImpl {
 
     @Override
     protected byte[] doWriteMessage() throws I2CPMessageException, IOException {
-        ByteArrayOutputStream os = new ByteArrayOutputStream(64);
+        ByteArrayStream os = new ByteArrayStream(4 * LIMITS);
         try {
             for (int i = 0; i < LIMITS; i++) {
                 DataHelper.writeLong(os, 4, data[i]);

core/java/src/net/i2p/data/i2cp/CreateLeaseSet2Message.java

@@ -1,6 +1,5 @@
 package net.i2p.data.i2cp;
 
-import java.io.ByteArrayOutputStream;
 import java.io.EOFException;
 import java.io.IOException;
 import java.io.InputStream;
@@ -19,6 +18,7 @@ import net.i2p.data.LeaseSet2;
 import net.i2p.data.MetaLeaseSet;
 import net.i2p.data.PrivateKey;
 import net.i2p.data.PublicKey;
+import net.i2p.util.ByteArrayStream;
 
 /**
  * Like CreateLeaseSetMessage, but supports both old
@@ -174,7 +174,7 @@ public class CreateLeaseSet2Message extends CreateLeaseSetMessage {
                 size += pk.length();
             }
         }
-        ByteArrayOutputStream os = new ByteArrayOutputStream(size);
+        ByteArrayStream os = new ByteArrayStream(size);
         try {
             _sessionId.writeBytes(os);
             os.write(_leaseSet.getType());

core/java/src/net/i2p/data/i2cp/CreateLeaseSetMessage.java

@@ -9,7 +9,6 @@ package net.i2p.data.i2cp;
  *
  */
 
-import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 
@@ -17,6 +16,7 @@ import net.i2p.data.DataFormatException;
 import net.i2p.data.LeaseSet;
 import net.i2p.data.PrivateKey;
 import net.i2p.data.SigningPrivateKey;
+import net.i2p.util.ByteArrayStream;
 
 /**
  * Defines the message a client sends to a router when authorizing
@@ -105,7 +105,7 @@ public class CreateLeaseSetMessage extends I2CPMessageImpl {
                  + _signingPrivateKey.length()
                  + PrivateKey.KEYSIZE_BYTES
                  + _leaseSet.size();
-        ByteArrayOutputStream os = new ByteArrayOutputStream(size);
+        ByteArrayStream os = new ByteArrayStream(size);
         try {
             _sessionId.writeBytes(os);
             _signingPrivateKey.writeBytes(os);

core/java/src/net/i2p/data/i2cp/DestReplyMessage.java

@@ -6,13 +6,13 @@ package net.i2p.data.i2cp;
  *
  */
 
-import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 
 import net.i2p.data.DataFormatException;
 import net.i2p.data.Destination;
 import net.i2p.data.Hash;
+import net.i2p.util.ByteArrayStream;
 
 /**
  * Response to DestLookupMessage.
@@ -76,7 +76,7 @@ public class DestReplyMessage extends I2CPMessageImpl {
                 return new byte[0];  // null response allowed
             return _hash.getData();
         }
-        ByteArrayOutputStream os = new ByteArrayOutputStream(_dest.size());
+        ByteArrayStream os = new ByteArrayStream(_dest.size());
         try {
             _dest.writeBytes(os);
         } catch (DataFormatException dfe) {

core/java/src/net/i2p/data/i2cp/DestroySessionMessage.java

@@ -9,11 +9,11 @@ package net.i2p.data.i2cp;
  *
  */
 
-import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 
 import net.i2p.data.DataFormatException;
+import net.i2p.util.ByteArrayStream;
 
 /**
  * Defines the message a client sends to a router when destroying
@@ -61,7 +61,7 @@ public class DestroySessionMessage extends I2CPMessageImpl {
     protected byte[] doWriteMessage() throws I2CPMessageException, IOException {
         if (_sessionId == null)
             throw new I2CPMessageException("Unable to write out the message as there is not enough data");
-        ByteArrayOutputStream os = new ByteArrayOutputStream(64);
+        ByteArrayStream os = new ByteArrayStream(2);
         try {
             _sessionId.writeBytes(os);
         } catch (DataFormatException dfe) {

core/java/src/net/i2p/data/i2cp/DisconnectMessage.java

@@ -9,12 +9,12 @@ package net.i2p.data.i2cp;
  *
  */
 
-import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 
 import net.i2p.data.DataFormatException;
 import net.i2p.data.DataHelper;
+import net.i2p.util.ByteArrayStream;
 
 /**
  * Defines the message a client sends to a router when destroying
@@ -48,7 +48,10 @@ public class DisconnectMessage extends I2CPMessageImpl {
 
     @Override
     protected byte[] doWriteMessage() throws I2CPMessageException, IOException {
-        ByteArrayOutputStream os = new ByteArrayOutputStream(64);
+        int len = 1;
+        if (_reason != null)
+            len += _reason.length();
+        ByteArrayStream os = new ByteArrayStream(len);
         try {
             DataHelper.writeString(os, _reason);
         } catch (DataFormatException dfe) {

core/java/src/net/i2p/data/i2cp/GetDateMessage.java

@@ -9,7 +9,6 @@ package net.i2p.data.i2cp;
  *
  */
 
-import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.Map;
@@ -17,6 +16,7 @@ import java.util.Properties;
 
 import net.i2p.data.DataFormatException;
 import net.i2p.data.DataHelper;
+import net.i2p.util.ByteArrayStream;
 import net.i2p.util.OrderedProperties;
 
 /**
@@ -99,7 +99,7 @@ public class GetDateMessage extends I2CPMessageImpl {
     protected byte[] doWriteMessage() throws I2CPMessageException, IOException {
         if (_version == null)
             return new byte[0];
-        ByteArrayOutputStream os = new ByteArrayOutputStream(_options != null ? 128 : 16);
+        ByteArrayStream os = new ByteArrayStream(_options != null ? 128 : (1 + 6));
         try {
             DataHelper.writeString(os, _version);
             if (_options != null && !_options.isEmpty())

core/java/src/net/i2p/data/i2cp/HostLookupMessage.java

@@ -5,7 +5,6 @@ package net.i2p.data.i2cp;
  * with no warranty of any kind, either expressed or implied.  
  */
 
-import java.io.ByteArrayOutputStream;
 import java.io.EOFException;
 import java.io.IOException;
 import java.io.InputStream;
@@ -13,6 +12,7 @@ import java.io.InputStream;
 import net.i2p.data.DataFormatException;
 import net.i2p.data.DataHelper;
 import net.i2p.data.Hash;
+import net.i2p.util.ByteArrayStream;
 
 /**
  * Request the router look up the dest for a hash
@@ -158,7 +158,7 @@ public class HostLookupMessage extends I2CPMessageImpl {
         } else {
             throw new I2CPMessageException("bad type");
         }
-        ByteArrayOutputStream os = new ByteArrayOutputStream(len);
+        ByteArrayStream os = new ByteArrayStream(len);
         try {
             _sessionId.writeBytes(os);
             DataHelper.writeLong(os, 4, _reqID);

core/java/src/net/i2p/data/i2cp/HostReplyMessage.java

@@ -6,7 +6,6 @@ package net.i2p.data.i2cp;
  *
  */
 
-import java.io.ByteArrayOutputStream;
 import java.io.EOFException;
 import java.io.IOException;
 import java.io.InputStream;
@@ -14,6 +13,7 @@ import java.io.InputStream;
 import net.i2p.data.DataFormatException;
 import net.i2p.data.DataHelper;
 import net.i2p.data.Destination;
+import net.i2p.util.ByteArrayStream;
 
 /**
  * Response to HostLookupMessage. Replaces DestReplyMessage.
@@ -135,7 +135,7 @@ public class HostReplyMessage extends I2CPMessageImpl {
                 throw new I2CPMessageException("Unable to write out the message as there is not enough data");
             len += _dest.size();
         }
-        ByteArrayOutputStream os = new ByteArrayOutputStream(len);
+        ByteArrayStream os = new ByteArrayStream(len);
         try {
             _sessionId.writeBytes(os);
             DataHelper.writeLong(os, 4, _reqID);

core/java/src/net/i2p/data/i2cp/ReportAbuseMessage.java

@@ -9,11 +9,11 @@ package net.i2p.data.i2cp;
  *
  */
 
-import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 
 import net.i2p.data.DataFormatException;
+import net.i2p.util.ByteArrayStream;
 
 /**
  * Defines the message a client sends to a router when asking the 
@@ -93,7 +93,11 @@ public class ReportAbuseMessage extends I2CPMessageImpl {
     protected byte[] doWriteMessage() throws I2CPMessageException, IOException {
         if ((_sessionId == null) || (_severity == null) || (_reason == null))
             throw new I2CPMessageException("Not enough information to construct the message");
-        ByteArrayOutputStream os = new ByteArrayOutputStream(32);
+        int len = 2 + 1 + 4 + 1;
+        String r = _reason.getReason();
+        if (r != null)
+            len += r.length();
+        ByteArrayStream os = new ByteArrayStream(len);
         try {
             _sessionId.writeBytes(os);
             _severity.writeBytes(os);

core/java/src/net/i2p/data/i2cp/RequestLeaseSetMessage.java

@@ -9,7 +9,6 @@ package net.i2p.data.i2cp;
  *
  */
 
-import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.Serializable;
@@ -21,6 +20,7 @@ import net.i2p.data.DataFormatException;
 import net.i2p.data.DataHelper;
 import net.i2p.data.Hash;
 import net.i2p.data.TunnelId;
+import net.i2p.util.ByteArrayStream;
 
 /**
  * Defines the message a router sends to a client to request that
@@ -38,7 +38,7 @@ public class RequestLeaseSetMessage extends I2CPMessageImpl {
     private Date _end;
 
     public RequestLeaseSetMessage() {
-        _endpoints = new ArrayList<TunnelEndpoint>();
+        _endpoints = new ArrayList<TunnelEndpoint>(6);
     }
 
     public SessionId getSessionId() {
@@ -119,7 +119,8 @@ public class RequestLeaseSetMessage extends I2CPMessageImpl {
     protected byte[] doWriteMessage() throws I2CPMessageException, IOException {
         if (_sessionId == null)
             throw new I2CPMessageException("Unable to write out the message as there is not enough data");
-        ByteArrayOutputStream os = new ByteArrayOutputStream(256);
+        int len = 2 + 1 + (_endpoints.size() * (32 + 4)) + 8;
+        ByteArrayStream os = new ByteArrayStream(len);
         try {
             _sessionId.writeBytes(os);
             os.write((byte) _endpoints.size());

core/java/src/net/i2p/data/i2cp/RequestVariableLeaseSetMessage.java

@@ -9,7 +9,6 @@ package net.i2p.data.i2cp;
  *
  */
 
-import java.io.ByteArrayOutputStream;
 import java.io.EOFException;
 import java.io.IOException;
 import java.io.InputStream;
@@ -19,6 +18,7 @@ import java.util.List;
 import net.i2p.data.DataFormatException;
 import net.i2p.data.DataHelper;
 import net.i2p.data.Lease;
+import net.i2p.util.ByteArrayStream;
 import net.i2p.util.VersionComparator;
 
 /**
@@ -38,7 +38,7 @@ public class RequestVariableLeaseSetMessage extends I2CPMessageImpl {
     private static final String MIN_VERSION = "0.9.7";
 
     public RequestVariableLeaseSetMessage() {
-        _endpoints = new ArrayList<Lease>();
+        _endpoints = new ArrayList<Lease>(6);
     }
 
     /**
@@ -109,7 +109,8 @@ public class RequestVariableLeaseSetMessage extends I2CPMessageImpl {
     protected byte[] doWriteMessage() throws I2CPMessageException, IOException {
         if (_sessionId == null)
             throw new I2CPMessageException("No data");
-        ByteArrayOutputStream os = new ByteArrayOutputStream(256);
+        int len = 2 + 1 + (_endpoints.size() * 44);
+        ByteArrayStream os = new ByteArrayStream(len);
         try {
             _sessionId.writeBytes(os);
             os.write((byte) _endpoints.size());

core/java/src/net/i2p/data/i2cp/SessionConfig.java

@@ -27,6 +27,7 @@ import net.i2p.data.Destination;
 import net.i2p.data.Signature;
 import net.i2p.data.SigningPrivateKey;
 import net.i2p.data.SigningPublicKey;
+import net.i2p.util.ByteArrayStream;
 import net.i2p.util.Clock;
 import net.i2p.util.Log;
 import net.i2p.util.OrderedProperties;
@@ -278,7 +279,7 @@ public class SessionConfig extends DataStructureImpl {
             Signature sig = getOfflineSignature();
             if (sig == null)
                 return false;
-            ByteArrayOutputStream baos = new ByteArrayOutputStream(128);
+            ByteArrayStream baos = new ByteArrayStream(6 + spk.length());
             try {
                 DataHelper.writeLong(baos, 4, expires / 1000);
                 DataHelper.writeLong(baos, 2, spk.getType().getCode());
@@ -323,7 +324,7 @@ public class SessionConfig extends DataStructureImpl {
         if (_options == null) return null;
         if (_creationDate == null) return null;
 
-        ByteArrayOutputStream out = new ByteArrayOutputStream();
+        ByteArrayOutputStream out = new ByteArrayOutputStream(512);
         try {
             //_log.debug("PubKey size for destination: " + _destination.getPublicKey().getData().length);
             //_log.debug("SigningKey size for destination: " + _destination.getSigningPublicKey().getData().length);

core/java/src/net/i2p/data/i2cp/SessionStatusMessage.java

@@ -9,13 +9,13 @@ package net.i2p.data.i2cp;
  *
  */
 
-import java.io.ByteArrayOutputStream;
 import java.io.EOFException;
 import java.io.IOException;
 import java.io.InputStream;
 
 import net.i2p.data.DataFormatException;
 import net.i2p.data.DataHelper;
+import net.i2p.util.ByteArrayStream;
 
 /**
  * Defines the message a router sends to a client indicating the
@@ -87,7 +87,7 @@ public class SessionStatusMessage extends I2CPMessageImpl {
     protected byte[] doWriteMessage() throws I2CPMessageException, IOException {
         if (_sessionId == null)
             throw new I2CPMessageException("Unable to write out the message as there is not enough data");
-        ByteArrayOutputStream os = new ByteArrayOutputStream(64);
+        ByteArrayStream os = new ByteArrayStream(3);
         try {
             _sessionId.writeBytes(os);
             os.write((byte) _status);

core/java/src/net/i2p/data/i2cp/SetDateMessage.java

@@ -9,13 +9,13 @@ package net.i2p.data.i2cp;
  *
  */
 
-import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.Date;
 
 import net.i2p.data.DataFormatException;
 import net.i2p.data.DataHelper;
+import net.i2p.util.ByteArrayStream;
 import net.i2p.util.Clock;
 
 /**
@@ -74,7 +74,7 @@ public class SetDateMessage extends I2CPMessageImpl {
     protected byte[] doWriteMessage() throws I2CPMessageException, IOException {
         if (_date == null)
             throw new I2CPMessageException("Unable to write out the message as there is not enough data");
-        ByteArrayOutputStream os = new ByteArrayOutputStream(32);
+        ByteArrayStream os = new ByteArrayStream(8 + 1 + 6);
         try {
             DataHelper.writeDate(os, _date);
             if (_version != null)

core/java/src/net/i2p/util/ByteArrayStream.java

@@ -18,6 +18,9 @@ public class ByteArrayStream extends ByteArrayOutputStream {
         super();
     }
 
+    /**
+     *  @param size if accurate, toByteArray() will be zero-copy
+     */
     public ByteArrayStream(int size) {
         super(size);
     }

router/java/src/net/i2p/router/message/GarlicMessageBuilder.java

@@ -8,7 +8,6 @@ package net.i2p.router.message;
  *
  */
 
-import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.util.Date;
 import java.util.HashSet;
@@ -37,6 +36,7 @@ import net.i2p.router.crypto.ratchet.MuxedSKM;
 import net.i2p.router.crypto.ratchet.RatchetSKM;
 import net.i2p.router.crypto.ratchet.RatchetSessionTag;
 import net.i2p.router.crypto.ratchet.ReplyCallback;
+import net.i2p.util.ByteArrayStream;
 import net.i2p.util.Log;
 
 /**
@@ -393,11 +393,11 @@ public class GarlicMessageBuilder {
      * @throws IllegalArgumentException on error
      */
     private static byte[] buildCloveSet(RouterContext ctx, GarlicConfig config) {
-        ByteArrayOutputStream baos;
+        ByteArrayStream baos;
         try {
             if (config instanceof PayloadGarlicConfig) {
                 byte clove[] = buildClove(ctx, (PayloadGarlicConfig)config);
-                baos = new ByteArrayOutputStream(clove.length + 16);
+                baos = new ByteArrayStream(1 + clove.length + 3 + 4 + 8);
                 baos.write((byte) 1);
                 baos.write(clove);
             } else {
@@ -417,7 +417,7 @@ public class GarlicMessageBuilder {
                 int len = 1;
                 for (int i = 0; i < cloves.length; i++)
                     len += cloves[i].length;
-                baos = new ByteArrayOutputStream(len + 16);
+                baos = new ByteArrayStream(1 + len + 3 + 4 + 8);
                 baos.write((byte) cloves.length);
                 for (int i = 0; i < cloves.length; i++)
                     baos.write(cloves[i]);

router/java/src/net/i2p/router/transport/ntcp/InboundEstablishState.java

@@ -33,6 +33,7 @@ import net.i2p.router.RouterContext;
 import net.i2p.router.networkdb.kademlia.FloodfillNetworkDatabaseFacade;
 import net.i2p.router.transport.crypto.DHSessionKeyBuilder;
 import static net.i2p.router.transport.ntcp.OutboundNTCP2State.*;
+import net.i2p.util.ByteArrayStream;
 import net.i2p.util.ByteCache;
 import net.i2p.util.Log;
 import net.i2p.util.SimpleByteCache;
@@ -456,7 +457,7 @@ class InboundEstablishState extends EstablishBase implements NTCP2Payload.Payloa
             long rtt = now - _con.getCreated();
             _peerSkew = (now - (tsA * 1000) - (rtt / 2) + 500) / 1000; 
 
-            ByteArrayOutputStream baos = new ByteArrayOutputStream(768);
+            ByteArrayStream baos = new ByteArrayStream(256 + 256 + 32 + 4 + 4);
             baos.write(_X);
             baos.write(_Y);
             baos.write(_context.routerHash().getData());