* Tunnel Building:

- Add getRecordCount() to TunnelBuildMessage and TunnelBuildReplyMessage so they can be extended. - New I2NP Messages VariableTunnelBuildMessage and VariableTunnelBuildReplyMessage, which contain the number of request slots in them. - Convert all static assumptions of 8 slots to getRecordCount() - Use the new VTBM if all hops in the tunnel and the OBEP or IBGW of the reply tunnel support it, and the tunnel is 4 hops or shorter. - Reply to a VTBM with a VTBRM of the same size - Make BuildReplyHandler static - Convert the currentlyBuilding List to a ConcurrentHashMap to speed reply lookups and eliminate a global lock; don't put fallback tunnels in there - Add new tunnel.corruptBuildReply stat - Various cleanups and javadoc Tested as compatible with current network, new messages untested.
2026-08-21 12:20:03 +00:00 · 2010-01-29 19:22:10 +00:00
parent 5dda915467
commit 56b3e6a993
12 changed files with 383 additions and 109 deletions
@@ -0,0 +1,71 @@
+package net.i2p.data.i2np;
+
+import java.io.IOException;
+
+import net.i2p.I2PAppContext;
+import net.i2p.data.ByteArray;
+import net.i2p.data.DataHelper;
+
+/**
+ * Transmitted from the new outbound endpoint to the creator through a
+ * reply tunnel
+ *
+ * @since 0.7.11
+ */
+public class VariableTunnelBuildReplyMessage extends TunnelBuildReplyMessage {
+    public static final int MESSAGE_TYPE = 24;
+
+    /** zero record count, will be set with readMessage() */
+    public VariableTunnelBuildReplyMessage(I2PAppContext context) {
+        super(context, 0);
+    }
+
+    public VariableTunnelBuildReplyMessage(I2PAppContext context, int records) {
+        super(context, records);
+    }
+
+    @Override
+    protected int calculateWrittenLength() { return 1 + super.calculateWrittenLength(); }
+
+    @Override
+    public int getType() { return MESSAGE_TYPE; }
+
+    public void readMessage(byte[] data, int offset, int dataSize, int type) throws I2NPMessageException, IOException {
+        if (type != MESSAGE_TYPE) 
+            throw new I2NPMessageException("Message type is incorrect for this message");
+        if (dataSize != calculateWrittenLength()) 
+            throw new I2NPMessageException("Wrong length (expects " + calculateWrittenLength() + ", recv " + dataSize + ")");
+        
+        int r = (int)DataHelper.fromLong(data, offset, 1);
+        if (r <= 0 || r > MAX_RECORD_COUNT)
+            throw new I2NPMessageException("Bad record count " + r);
+        RECORD_COUNT = r;
+        _records = new ByteArray[RECORD_COUNT];
+        super.readMessage(data, offset + 1, dataSize, TunnelBuildMessage.MESSAGE_TYPE);
+    }
+    
+    protected int writeMessageBody(byte[] out, int curIndex) throws I2NPMessageException {
+        int remaining = out.length - (curIndex + calculateWrittenLength());
+        if (remaining < 0)
+            throw new I2NPMessageException("Not large enough (too short by " + remaining + ")");
+        if (RECORD_COUNT <= 0 || RECORD_COUNT > MAX_RECORD_COUNT)
+            throw new I2NPMessageException("Bad record count " + RECORD_COUNT);
+        DataHelper.toLong(out, curIndex, 1, RECORD_COUNT);
+        // can't call super, written length check will fail
+        //return super.writeMessageBody(out, curIndex + 1);
+        for (int i = 0; i < RECORD_COUNT; i++) {
+            System.arraycopy(_records[i].getData(), _records[i].getOffset(), out, curIndex, RECORD_SIZE);
+            curIndex += RECORD_SIZE;
+        }
+        return curIndex;
+    }
+    
+    @Override
+    public String toString() {
+        StringBuilder buf = new StringBuilder(64);
+        buf.append("[VariableTunnelBuildReplyMessage: " +
+                   "\n\tRecords: ").append(getRecordCount())
+           .append(']');
+        return buf.toString();
+    }
+}