i2p.i2p/router/java/src/net/i2p/router/tunnel/BuildMessageTest.java

package net.i2p.router.tunnel;

import java.util.*;
import net.i2p.I2PAppContext;
import net.i2p.data.*;
import net.i2p.data.i2np.*;
import net.i2p.util.Log;

/**
 * Simple test to create an encrypted TunnelBuildMessage, decrypt its layers (as it would be
 * during transmission), inject replies, then handle the TunnelBuildReplyMessage (unwrapping
 * the reply encryption and reading the replies).
 */
public class BuildMessageTest {
    private Hash _peers[];
    private PrivateKey _privKeys[];
    private PublicKey _pubKeys[];
    private Hash _replyRouter;
    private long _replyTunnel;
    
    public static void main(String args[]) {
        BuildMessageTest test = new BuildMessageTest();
        try {
            test.runTest();
        } catch (Exception e) { e.printStackTrace(); }
    }
    
    private void runTest() {
        I2PAppContext ctx = I2PAppContext.getGlobalContext();
        Log log = ctx.logManager().getLog(getClass());
        
        List order = pickOrder(ctx);
        
        TunnelCreatorConfig cfg = createConfig(ctx);
        _replyRouter = new Hash();
        byte h[] = new byte[Hash.HASH_LENGTH];
        Arrays.fill(h, (byte)0xFF);
        _replyRouter.setData(h);
        _replyTunnel = 42;
        
        // populate and encrypt the message
        BuildMessageGenerator gen = new BuildMessageGenerator();
        TunnelBuildMessage msg = new TunnelBuildMessage(ctx);
        for (int i = 0; i < BuildMessageGenerator.ORDER.length; i++) {
            int hop = ((Integer)order.get(i)).intValue();
            PublicKey key = null;
            if (hop < _pubKeys.length)
                key = _pubKeys[hop];
            gen.createRecord(i, hop, msg, cfg, _replyRouter, _replyTunnel, ctx, key);
        }
        gen.layeredEncrypt(ctx, msg, cfg, order);
        
        log.debug("\n================================================================" +
                  "\nMessage fully encrypted" + 
                  "\n================================================================");
        
        // now msg is fully encrypted, so lets go through the hops, decrypting and replying
        // as necessary
        
        for (int i = 0; i < cfg.getLength(); i++) {
            BuildMessageProcessor proc = new BuildMessageProcessor();
            // this not only decrypts the current hop's record, but encrypts the other records
            // with the reply key
            BuildRequestRecord req = proc.decrypt(ctx, msg, _peers[i], _privKeys[i]);
            if (req == null) {
                // no records matched the _peers[i], or the decryption failed
                throw new RuntimeException("foo @ " + i);
            }
            long ourId = req.readReceiveTunnelId();
            byte replyIV[] = req.readReplyIV();
            long nextId = req.readNextTunnelId();
            Hash nextPeer = req.readNextIdentity();
            boolean isInGW = req.readIsInboundGateway();
            boolean isOutEnd = req.readIsOutboundEndpoint();
            long time = req.readRequestTime();
            long now = (ctx.clock().now() / (60l*60l*1000l)) * (60*60*1000);
            int ourSlot = -1;
            
            BuildResponseRecord resp = new BuildResponseRecord();
            byte reply[] = resp.create(ctx, 0, req.readReplyKey(), req.readReplyIV());
            for (int j = 0; j < TunnelBuildMessage.RECORD_COUNT; j++) {
                if (msg.getRecord(j) == null) {
                    ourSlot = j;
                    msg.setRecord(j, new ByteArray(reply));
                    break;
                }
            }
            
            log.debug("Read slot " + ourSlot + " containing hop " + i + " @ " + _peers[i].toBase64() 
                      + " receives on " + ourId 
                      + " w/ replyIV " + Base64.encode(replyIV) + " sending to " + nextId
                      + " on " + nextPeer.toBase64()
                      + " inGW? " + isInGW + " outEnd? " + isOutEnd + " time difference " + (now-time));
        }
        
        
        log.debug("\n================================================================" +
                  "\nAll hops traversed and replies gathered" +
                  "\n================================================================");
        
        // now all of the replies are populated, toss 'em into a reply message and handle it
        TunnelBuildReplyMessage reply = new TunnelBuildReplyMessage(ctx);
        for (int i = 0; i < TunnelBuildMessage.RECORD_COUNT; i++)
            reply.setRecord(i, msg.getRecord(i));
       
        BuildReplyHandler handler = new BuildReplyHandler();
        int statuses[] = handler.decrypt(ctx, reply, cfg, order);
        if (statuses == null) throw new RuntimeException("bar");
        boolean allAgree = true;
        for (int i = 0; i < cfg.getLength(); i++) {
            Hash peer = cfg.getPeer(i);
            int record = ((Integer)order.get(i)).intValue();
            if (statuses[record] != 0)
                allAgree = false;
            //else
            //    penalize peer according to the rejection cause    
        }
        
        log.debug("\n================================================================" +
                  "\nAll peers agree? " + allAgree + 
                  "\n================================================================");
    }
    
    private static final List pickOrder(I2PAppContext ctx) {
        // pseudorandom, yet consistent (so we can be repeatable)
        List rv = new ArrayList(8);
        rv.add(new Integer(2));
        rv.add(new Integer(4));
        rv.add(new Integer(6));
        rv.add(new Integer(0));
        rv.add(new Integer(1));
        rv.add(new Integer(3));
        rv.add(new Integer(5));
        rv.add(new Integer(7));
        return rv;
    }
    
    private TunnelCreatorConfig createConfig(I2PAppContext ctx) {
        return configOutbound(ctx);
    }
    private TunnelCreatorConfig configOutbound(I2PAppContext ctx) {
        _peers = new Hash[4];
        _pubKeys = new PublicKey[_peers.length];
        _privKeys = new PrivateKey[_peers.length];
        for (int i = 0; i < _peers.length; i++) {
            byte buf[] = new byte[Hash.HASH_LENGTH];
            Arrays.fill(buf, (byte)i); // consistent for repeatability
            Hash h = new Hash(buf);
            _peers[i] = h;
            Object kp[] = ctx.keyGenerator().generatePKIKeypair();
            _pubKeys[i] = (PublicKey)kp[0];
            _privKeys[i] = (PrivateKey)kp[1];
        }
        
        TunnelCreatorConfig cfg = new TunnelCreatorConfig(null, _peers.length, false);
        long now = ctx.clock().now();
        // peers[] is ordered endpoint first, but cfg.getPeer() is ordered gateway first
        for (int i = 0; i < _peers.length; i++) {
            cfg.setPeer(i, _peers[i]);
            HopConfig hop = cfg.getConfig(i);
            hop.setExpiration(now+10*60*1000);
            hop.setIVKey(ctx.keyGenerator().generateSessionKey());
            hop.setLayerKey(ctx.keyGenerator().generateSessionKey());
            hop.setReplyKey(ctx.keyGenerator().generateSessionKey());
            byte iv[] = new byte[BuildRequestRecord.IV_SIZE];
            Arrays.fill(iv, (byte)i); // consistent for repeatability
            hop.setReplyIV(new ByteArray(iv));
            hop.setReceiveTunnelId(new TunnelId(i+1));
        }
        return cfg;
    }
}