* I2CP, HostsTxtNamingService, I2PTunnel:

Implement Base32 Hash hostnames, via the naming service.
      Names are of the form [52-characters].i2p, where
      the 52 characters are the Base32 representation of our
      256-byte hash. The client requests a lookup of the hash
      via a brief I2CP session using new I2CP request/reply
      messages. The router looks up the leaseset for the hash
      to convert the hash to a dest. Convert the I2PTunnel
      'preview' links to use Base32 hostnames as a
      demonstration.

router/java/src/net/i2p/router/client/ClientMessageEventListener.java

@@ -11,6 +11,7 @@ package net.i2p.router.client;
 import net.i2p.data.Payload;
 import net.i2p.data.i2cp.CreateLeaseSetMessage;
 import net.i2p.data.i2cp.CreateSessionMessage;
+import net.i2p.data.i2cp.DestLookupMessage;
 import net.i2p.data.i2cp.DestroySessionMessage;
 import net.i2p.data.i2cp.GetDateMessage;
 import net.i2p.data.i2cp.I2CPMessage;
@@ -78,6 +79,9 @@ class ClientMessageEventListener implements I2CPMessageReader.I2CPMessageEventLi
             case DestroySessionMessage.MESSAGE_TYPE:
                 handleDestroySession(reader, (DestroySessionMessage)message);
                 break;
+            case DestLookupMessage.MESSAGE_TYPE:
+                handleDestLookup(reader, (DestLookupMessage)message);
+                break;
             default:
                 if (_log.shouldLog(Log.ERROR))
                     _log.error("Unhandled I2CP type received: " + message.getType());
@@ -85,13 +89,14 @@ class ClientMessageEventListener implements I2CPMessageReader.I2CPMessageEventLi
     }
 
     /**
-     * Handle notifiation that there was an error
+     * Handle notification that there was an error
      *
      */
     public void readError(I2CPMessageReader reader, Exception error) {
         if (_runner.isDead()) return;
         if (_log.shouldLog(Log.ERROR))
             _log.error("Error occurred", error);
+        // Is this is a little drastic for an unknown message type?
         _runner.stopRunning();
     }
     
@@ -228,6 +233,10 @@ class ClientMessageEventListener implements I2CPMessageReader.I2CPMessageEventLi
         _runner.leaseSetCreated(message.getLeaseSet());
     }
 
+    private void handleDestLookup(I2CPMessageReader reader, DestLookupMessage message) {
+        _context.jobQueue().addJob(new LookupDestJob(_context, _runner, message.getHash()));
+    }
+
     // this *should* be mod 65536, but UnsignedInteger is still b0rked.  FIXME
     private final static int MAX_SESSION_ID = 32767;
 

router/java/src/net/i2p/router/client/LookupDestJob.java

@@ -0,0 +1,54 @@
+/*
+ * Released into the public domain 
+ * with no warranty of any kind, either expressed or implied.  
+ */
+package net.i2p.router.client;
+
+import net.i2p.data.Destination;
+import net.i2p.data.Hash;
+import net.i2p.data.LeaseSet;
+import net.i2p.data.i2cp.DestReplyMessage;
+import net.i2p.data.i2cp.I2CPMessageException;
+import net.i2p.router.JobImpl;
+import net.i2p.router.RouterContext;
+
+/**
+ * Look up the lease of a hash, to convert it to a Destination for the client
+ */
+class LookupDestJob extends JobImpl {
+    private ClientConnectionRunner _runner;
+    private Hash _hash;
+
+    public LookupDestJob(RouterContext context, ClientConnectionRunner runner, Hash h) {
+        super(context);
+        _runner = runner;
+        _hash = h;
+    }
+    
+    public String getName() { return "LeaseSet Lookup for Client"; }
+    public void runJob() {
+        DoneJob done = new DoneJob(getContext());
+        getContext().netDb().lookupLeaseSet(_hash, done, done, 10*1000);
+    }
+
+    private class DoneJob extends JobImpl {
+        public DoneJob(RouterContext enclosingContext) { 
+            super(enclosingContext);
+        }
+        public String getName() { return "LeaseSet Lookup Reply to Client"; }
+        public void runJob() {
+            LeaseSet ls = getContext().netDb().lookupLeaseSetLocally(_hash);
+            if (ls != null)
+                returnDest(ls.getDestination());
+            else
+                returnDest(null);
+        }
+    }
+
+    private void returnDest(Destination d) {
+        DestReplyMessage msg = new DestReplyMessage(d);
+        try {
+            _runner.doSend(msg);
+        } catch (I2CPMessageException ime) {}
+    }
+}