/**
* @param p the AHPacket to route
* @param from The edge the packet came from
* @param deliverlocally set to true if the local node should Announce it
* @return the number of edges the packet it Sent on.
*/
public int Route(Edge from, AHPacket p, out bool deliverlocally)
{
Edge next = null;
deliverlocally = false;
int sent = 0;
/* We can only route if it is a DirectionalAddress and we have
* structured connections
*/
try {
DirectionalAddress dir_add = (DirectionalAddress) p.Destination;
/* We need to do a few atomic operations on the ConnectionTable */
ConnectionList structs = _con_tab.GetConnections(ConnectionType.Structured);
Connection next_con = null;
if ( dir_add.Bearing == DirectionalAddress.Direction.Left ) {
//Get the left structured neighbor of us:
next_con = structs.GetLeftNeighborOf(_local);
if( next_con.Edge == from ) {
//skip the person it came from
next_con = structs.GetLeftNeighborOf(next_con.Address);
}
}
else if (dir_add.Bearing == DirectionalAddress.Direction.Right) {
//Get the left structured neighbor of us:
next_con = structs.GetRightNeighborOf(_local);
if( next_con.Edge == from ) {
//skip the person it came from
next_con = structs.GetRightNeighborOf(next_con.Address);
}
}
if (next_con != null ) {
//Here is the edge to go to next
next = next_con.Edge;
}
if( p.HasOption( AHPacket.AHOptions.Path ) ) {
deliverlocally = true;
}
else if( p.HasOption( AHPacket.AHOptions.Last ) ) {
if( next == null || p.Hops == p.Ttl ) {
deliverlocally = true;
}
}
if ( (next != null)
&& (p.Hops < p.Ttl) //Send only packets with some Ttl left
&& (next != from) ) { //Don't send it the way it came no matter what
//Increment the hops :
//If we send it, set sent to 1
next.Send( p.IncrementHops() );
sent = 1;
}
}
catch(System.Exception) {
//_log.Error("DirectionalRouter exception:", x);
if( next != null && next.IsClosed ) {
//The edge is closed but not yet removed from the ConnectionTable
//remove it and try again
_con_tab.Disconnect(next);
return Route(from, p, out deliverlocally);
}
}
return sent;
}
/**
* Route the packet p which came from edge e, and set
* deliverlocally to true if this packet should be delivered
* to the local node.
*
* The routing algorithm can be summarized:
* <ol>
* <li>If Hops <= 1, route closest to the dest, other than previous, else:</li>
* <li>If the closest is closer than the previous, route to closest, else:</li>
* <li>stop</li>
* </ol>
*
* Local delivery is done anytime there is either no next hop,
* or the next hop is further from the destination than we are.
*
* @return the number of edges we send the packet to
*/
public int Route(Edge prev_e, AHPacket p, out bool deliverlocally)
{
#if AHROUTER_DEBUG
bool debug = false;
if (p.PayloadType == AHPacket.Protocol.ReqRep) {
Console.Error.WriteLine("{0}: We have a ReqRep packet to route at: {1}", _local, System.DateTime.Now);
//ReqrepManager.DebugPacket(_local, p, prev_e);
debug = true;
} else if (p.PayloadType == AHPacket.Protocol.IP) {
Console.Error.WriteLine("{0}: We have a IP to route at: {1}", _local, System.DateTime.Now);
debug = true;
} else if (p.PayloadType == AHPacket.Protocol.Forwarding) {
Console.Error.WriteLine("{0}: We have a Forwarding to route at: {1}", _local, System.DateTime.Now);
debug = true;
} else if (p.PayloadType == AHPacket.Protocol.Tunneling) {
Console.Error.WriteLine("{0}: We have a Tunnel to route at: {1}", _local, System.DateTime.Now);
debug = true;
}
#endif
Connection next_con = null; //the next connection to send the packet to
deliverlocally = false;
AHAddress dest = (AHAddress)p.Destination;
/*
* The following cases don't require us to consult the Connection table
*/
short hops = p.Hops;
short ttl = p.Ttl;
if( hops > ttl ) {
//This should never have gotten here:
Console.Error.WriteLine(
"Bad Packet from: {0}, hops({1}) > ttl({2})", prev_e, hops, ttl);
return 0;
}
else if ( _local.Equals(dest) ) {
//This packet is for us! Woo hoo!
//There is no option that does not mean deliver in this case
deliverlocally = true;
//We can stop routing now, no one is closer than us.
#if AHROUTER_DEBUG
if (debug) {
Console.Error.WriteLine("Delloc: {0}\n from: {1}\n delloc: {2}",
p,prev_e,deliverlocally);
Console.Error.WriteLine("{0}: We are the destination, WOW!", _local);
}
#endif
return 0;
}
else if( hops == ttl ) {
//We are the last to route the packet.
if( p.HasOption( AHPacket.AHOptions.Last ) ) {
/*
* No need to check any routing tables. We get it
*/
deliverlocally = true;
#if AHROUTER_DEBUG
if (debug) Console.Error.WriteLine("{0}: TTL expired. Still deliverlocally (option Last).", _local);
#endif
return 0;
}
else {
//We only deliver it if we are the nearest.
//We check this below.
}
}
CacheKey k = new CacheKey(dest, prev_e, p.Options );
//We've already checked hops == ttl, so we can ignore them for now
CachedRoute cr = null;
lock( _sync ) {
//This looks like a Hashtable, but it's a Cache,
//and we can't read from it without locking it
cr = (CachedRoute)_route_cache[ k ];
}
if( cr != null ) {
//Awesome, we already know the path to this node.
//This cuts down on latency
next_con = cr.Route;
deliverlocally = cr.DeliverLocally;
#if AHROUTER_DEBUG
if (debug)
{
if (next_con != null) {
Console.Error.WriteLine("{0}: We found a cached route. local delivery: {1}, next_con: {2}.",
_local, deliverlocally, next_con.Address);
} else {
Console.Error.WriteLine("{0}: We found a cached route. local delivery: {1}, next_con = null.",
_local, deliverlocally);
}
}
#endif
}
else {
/*
* else we know hops < ttl, we can route:
* We now need to check the ConnectionTable
*/
next_con = _tab.GetConnection(ConnectionType.Leaf, dest);
if( next_con == null ) {
ConnectionList structs = _tab.GetConnections(ConnectionType.Structured);
/*
* We do not have a leaf connection to use, now we must
* find a Structured connection over which to route the packet
*/
#if AHROUTER_DEBUG
if (debug) Console.Error.WriteLine("{0}: We do not have a leaf connection.", _local);
#endif
int dest_idx = structs.IndexOf(dest);
if( dest_idx >= 0 ) {
//We actually have a connection to this node:
#if AHROUTER_DEBUG
if (debug) Console.Error.WriteLine("{0}: We have a structured connection to destination.", _local);
#endif
next_con = structs[dest_idx];
}
else if( structs.Count == 0 ) {
//We don't have any structured connections. I guess we are the closest:
deliverlocally = true;
next_con = null;
}
else {
//dest_idx is not in the table:
#if AHROUTER_DEBUG
if (debug) Console.Error.WriteLine("{0}: We do not have a structured connection to destination.",
_local);
#endif
dest_idx = ~dest_idx;
/*
* Here are the right and left neighbors of the destination
* left is increasing, right is decreasing.
* Remember the ConnectionTable wraps around, so no need to worry
* about the size of index
*/
int left_idx = dest_idx;
Connection left_n = structs[left_idx];
#if AHROUTER_DEBUG
if (debug && left_n != null) Console.Error.WriteLine("{0}: key left connection: {1}.",
_local, left_n.Address);
#endif
int right_idx = dest_idx - 1;
Connection right_n = structs[right_idx];
#if AHROUTER_DEBUG
if (debug && right_n != null) Console.Error.WriteLine("{0}: key right connection: {1}.",
_local, right_n.Address);
#endif
//We check the a couple of connections:
BigInteger l_dist = dest.DistanceTo((AHAddress)left_n.Address).abs();
BigInteger r_dist = dest.DistanceTo((AHAddress)right_n.Address).abs();
Connection closest_con;
Connection other_con;
BigInteger closest_dist;
BigInteger other_dist;
if( l_dist < r_dist ) {
closest_con = left_n;
other_con = right_n;
closest_dist = l_dist;
other_dist = r_dist;
#if AHROUTER_DEBUG
if (debug) Console.Error.WriteLine("{0}: Going the left way (since it is closer).", _local);
#endif
}
else {
closest_con = right_n;
other_con = left_n;
closest_dist = r_dist;
other_dist = l_dist;
#if AHROUTER_DEBUG
if (debug) Console.Error.WriteLine("{0}: Going the right way (since it is closer).", _local);
#endif
}
/**
* Here we consider the various routing modes
*/
if( p.HasOption( AHPacket.AHOptions.Greedy ) ) {
#if AHROUTER_DEBUG
if (debug) Console.Error.WriteLine("{0}: Greedy routing mode.", _local);
#endif
/*
* We pass it ONLY IF we can get it closer than we are.
*/
BigInteger our_dist = dest.DistanceTo(_local).abs();
if( closest_dist < our_dist ) {
if( closest_con.Edge != prev_e ) {
#if AHROUTER_DEBUG
if (debug) Console.Error.WriteLine("{0}: Greedy. Closest distance is lesser than our distance.",
_local);
#endif
next_con = closest_con;
}
else {
#if AHROUTER_DEBUG
if (debug) Console.Error.WriteLine("Got wrong greedy packet from: {0}", prev_e);
#endif
//This should never happen, a buggy client must have given
//us a packet they shouldn't have:
Console.Error.WriteLine("Got wrong greedy packet from: {0}", prev_e);
next_con = null;
}
deliverlocally = false;
}
else {
//We keep it.
#if AHROUTER_DEBUG
if (debug) Console.Error.WriteLine("{0}: Closest distance not lesser than us. Lets keep it.",
_local);
#endif
next_con = null;
deliverlocally = true;
}
}
else {
#if AHROUTER_DEBUG
if (debug) Console.Error.WriteLine("{0}: Annealing routing mode.", _local);
#endif
//All the other routing modes use the Annealing rule
#if AHROUTER_DEBUG
if (debug) {
if (_our_left_n != null) {
Console.Error.WriteLine("{0}: our left connection: {1}", _local, _our_left_n.Address);
} else {
Console.Error.WriteLine("{0}: our left connection: null");
}
try {
Console.Error.WriteLine("{0}: Testing == between: {1} and {2}, equality: {3}",
_local, left_n.Address, _our_left_n.Address,
(left_n == _our_left_n));
Console.Error.WriteLine("{0}: Operand 1, hashcode: {1}, tostring(): {2}",
_local, left_n.GetHashCode(), left_n);
Console.Error.WriteLine("{0}: Operand 2, hashcode: {1}, tostring(): {2}",
_local, _our_left_n.GetHashCode(), _our_left_n);
Console.Error.WriteLine("{0}: Hashcode equality: {1}", _local, (left_n.GetHashCode() == _our_left_n.GetHashCode()));
} catch(System.Exception e) {
Console.Error.WriteLine("{0}: excption in debugging code!", _local);
}
}
#endif
if( left_n == _our_left_n ) {
#if AHROUTER_DEBUG
if (debug) Console.Error.WriteLine("{0}: I am adjacent to the destination (matching neighbors)", _local);
#endif
/*
* We share a common left neighbor, so we should deliver locally
* This is the only case where we should deliver locally,
* otherwise there is at least one node on either side of the
* target, so one of them should probably get the packet.
*/
deliverlocally = true;
#if AHROUTER_DEBUG
if (debug) Console.Error.WriteLine("{0}: Local delivery for sure. Who else gets it.", _local);
#endif
//The next step should be the node on the "other side"
if( _local.IsLeftOf( dest ) ) {
next_con = right_n;
#if AHROUTER_DEBUG
if (debug) {
if (next_con != null) {
Console.Error.WriteLine("{0}: Adjacent, also give to the guy on right: {1}", _local, next_con.Address);
} else {
Console.Error.WriteLine("{0}: Adjacent, also give to the guy on right: null", _local);
}
}
#endif
}
else {
next_con = left_n;
#if AHROUTER_DEBUG
if (debug) {
if (next_con != null) {
Console.Error.WriteLine("{0}: Adjacent, also give to the guy on left: {1}", _local, next_con.Address);
} else {
Console.Error.WriteLine("{0}: Adjacent, also give to the guy on left: null", _local);
}
}
#endif
}
if( prev_e == next_con.Edge ) {
//Don't send it back the way it came
#if AHROUTER_DEBUG
if (debug) Console.Error.WriteLine("{0}: Adjacent, dont send it back", _local);
#endif
next_con = null;
}
}
else if ( hops == 0 ) {
/*
* This is the case that we sent the packet, and we are not
* a neighbor of the packet (the previous case)
* So, the closest_con must be good since we are the source
*/
next_con = closest_con;
}
else if (hops <= _MAX_UPHILL_HOPS ) {
/*
* We will allow the packet to go uphill (get further from the source)
* at first, but this has to stop in order to prevent loops
*
* This may help the network form in the massive join case, or under
* heavy churn. @todo analyze approaches for improving stabilization
* in massively disordered cases.
*/
if( closest_con.Edge != prev_e ) {
//Awesome. This is an easy case...
next_con = closest_con;
}
else {
/*
* Look at the two next closest and choose the minimum distance of
* the three
*/
int sc_idx = -1;
if( closest_con == right_n ) {
//move one over
sc_idx = right_idx - 1;
}
else {
//Must be the left:
sc_idx = left_idx + 1;
}
Connection second_closest = structs[sc_idx];
BigInteger second_dist =
dest.DistanceTo( (AHAddress)second_closest.Address).abs();
if( second_dist < other_dist ) {
other_con = second_closest;
}
if( other_con.Edge != prev_e ) {
//If we only have one neighbor,
//other and closest might be the same
next_con = other_con;
}
else {
//We just can't win...
next_con = null;
}
}
}
else {
/*
* This is the case where we are not a neighbor of the destination
* according to our table, and the packet has taken at least 2 hops.
*/
deliverlocally = false;
if( ( closest_con.Edge == prev_e )
&& ( other_con.Edge != prev_e ) ) {
closest_dist = other_dist;
closest_con = other_con;
}
Connection prev = _tab.GetConnection(prev_e);
if( prev != null ) {
BigInteger prev_dist = dest.DistanceTo( (AHAddress)prev.Address ).abs();
if( closest_dist >= prev_dist ) {
//Don't send it if you can't get it closer than it was before
next_con = null;
}
else {
next_con = closest_con;
}
}
else {
//This is the case that we don't have a connection
//on the Edge the packet came from, this shouldn't happen,
//but it is not a disaster.
next_con = closest_con;
}
}//End of non-neareast neighbor case
}//End of Annealing case
}//End of the case where we had to find a near route
}
else {
//We can route directly to the destination.
}
/*
* We update the route cache with the most recent Edge to send to
* that destination.
*/
lock(_sync ) {
_route_cache[k] = new CachedRoute(next_con, deliverlocally);
}
}//End of cache check
//Here are the other modes:
if( p.HasOption( AHPacket.AHOptions.Last ) ) {
if( next_con == null ) {
deliverlocally = true;
}
else {
deliverlocally = false;
}
}
else if( p.HasOption( AHPacket.AHOptions.Path ) ) {
deliverlocally = true;
}
else if( p.HasOption( AHPacket.AHOptions.Exact ) ) {
if( _local.Equals(dest) ) {
deliverlocally = true;
next_con = null;
}
else {
deliverlocally = false;
}
}
/*
* Now we have next_con if we can send it somewhere closer.
*/
try {
if( next_con != null && (hops < ttl) ) {
//We can send it on
next_con.Edge.Send( p.IncrementHops() );
#if AHROUTER_DEBUG
if (debug) {
Console.Error.WriteLine("Sending {0}\n from: {1} to: {2}\n delloc: {3}",
p,prev_e,next_con,deliverlocally);
}
#endif
return 1;
}
else {
#if AHROUTER_DEBUG
if (debug) {
Console.Error.WriteLine("Not sending {0}\n from: {1}\n delloc: {2}",
p,prev_e,deliverlocally);
}
#endif
return 0;
}
}
catch(EdgeException x) {
if( !x.IsTransient ) {
/*
Console.Error.WriteLine(x);
Console.Error.WriteLine("{0}: Edge exception encountered while sending from: {1} to: {3}, delloc: {2}",
_local,prev_e,deliverlocally, next_con);
*/
/*
* This is a permanent error
* This edge gave us problems, let's try again after we've closed
* that bad edge.
*
* Make sure the cache is flushed and we reset out nearest left
* neighbor
*/
next_con.Edge.Close();
ConnectionTableChangeHandler(null, null);
return this.Route(prev_e, p, out deliverlocally);
} else {
/**
* In the case of a transient problem, we just drop the
* packet.
* @todo should we send some error message, or retry later?
*/
return 0;
}
}
}
/**
* Create an AHPacket representing an Error
*/
protected AHPacket CreateErrorPacket(Address destination,
short sourcetid,
short desttid,
Error err) {
byte[] body = new byte[1024];
//Write the our TID
NumberSerializer.WriteShort(sourcetid, body, 0);
//Write the other TID
NumberSerializer.WriteShort(desttid, body, 2);
int size = 4;
size += err.CopyTo(body, 4);
//Send the error:
AHPacket resp = new AHPacket(0, 32, _node.Address, destination,
AHPacket.Protocol.Tftp, body, 0, size);
return resp;
}
/**
* Send an acknowledgement for the given block in the given transfer
*/
protected void SendAck(Request req, int block) {
byte[] body = new byte[8];
//Write the our TID
NumberSerializer.WriteShort(req.LocalTID, body, 0);
//Write the other TID
NumberSerializer.WriteShort(req.PeerTID, body, 2);
//Write the OP:
NumberSerializer.WriteShort((short)Opcode.Ack, body, 4);
//Write the Block number:
NumberSerializer.WriteShort((short)block, body, 6);
AHPacket resp = new AHPacket(0, 32, _node.Address, req.Peer,
AHPacket.Protocol.Tftp, body);
_node.Send(resp);
}
/**
* Implementing from IAHPacketHandler
* This is where we do the meat of the operating
*/
public void HandleAHPacket(object node, AHPacket p, Edge from) {
Node n = (Node)node;
Stream packet_data = p.PayloadStream;
short peer_tid = NumberSerializer.ReadShort(packet_data);
short local_tid = NumberSerializer.ReadShort(packet_data);
Opcode op = (Opcode)NumberSerializer.ReadShort(packet_data);
/**
* If there is any Error, an exception is thrown and the
* Error is sent to the node which sent us this packet
*/
Error err = null;
//This is the Request to which this packet is associated
Request req = null;
try {
if( local_tid == DefaultTID ) {
/**
* This is a new request being made to us from a remote node
*/
lock( _sync ) {
//Check to see if this request is a duplicate:
foreach(Request openr in _open_requests) {
if( openr.Peer.Equals(p.Source) &&
(openr.PeerTID == peer_tid) ) {
req = openr;
/**
* We need to send an Error response when we
* get the same TID from the same Address.
* This must be a duplicate packet.
*/
err = new Error(Error.Code.NotDefined, "Duplicate Source TID");
throw new Exception();
}
}
}
//This is a new operation
local_tid = GetNextTID();
//We need to parse the request and assign a new TID to this transfer
req = new Request(peer_tid, local_tid, op, p.Source, packet_data);
//If we get here, this is a new request
IAcceptor acc = null;
if( op == Opcode.ReadReq ) {
acc = _read_acc;
}
else if( op == Opcode.WriteReq ) {
acc = _write_acc;
}
if( acc != null ) {
_open_requests.Add(req);
acc.Accept(req, this);
}
else {
//Something bad happened
err = new Error(Error.Code.IllegalOp, "Unknown Opcode");
throw new Exception();
}
}
else if (_tid_to_status.ContainsKey(local_tid) ) {
//This is continuing an existing transfer
Status stat = (Status)_tid_to_status[local_tid];
if( stat == null) {
/**
* Status is null until a Request is accepted or denied.
* This request is either a (lucky) bug or an attack.
* You see, there is no way for the Peer to know which
* TID we are using when status is null. This only happens
* when a TID has been assigned locally, but not yet sent
* over the network. Hence, the Peer made a lucky guess.
*/
Error error = new Error(Error.Code.UnknownTID, "say what?");
AHPacket resp = CreateErrorPacket(p.Source, DefaultTID, peer_tid, error);
_node.Send(resp);
}
else {
req = stat.Request;
short block;
switch(op) {
case Opcode.Data:
///@todo consider carefully that this works in both directions
///@todo make all blocks ushort (so we can use an int == -1 to initialize)
block = NumberSerializer.ReadShort(packet_data);
/**
* When data comes, we send an Ack
*/
lock( stat ) {
if( stat.LastBlockNumber == block ) {
/*
* This is a block we have already seen
*/
SendAck(req, block);
}
else if( stat.PendingBlock == block ) {
//We are already dealing with this data
//So, we do nothing here
}
else {
/*
* This is a new Data block to us!
* Write it to disk and then send the Ack
*/
StreamState ws = new StreamState();
stat.StartBlock(block, ws);
//This is new data we have not yet seen
ws.Stat = stat;
ws.Block = block;
ws.Data = new byte[ stat.Request.Blksize ];
ws.Offset = 0;
//The packet data is a MemoryStream which never blocks:
ws.Size = packet_data.Read(ws.Data, 0, stat.Request.Blksize);
stat.Data.BeginWrite(ws.Data, ws.Offset, ws.Size,
new AsyncCallback(this.WriteHandler),
ws);
}
}
break;
case Opcode.Ack:
block = NumberSerializer.ReadShort(packet_data);
/**
* When an Ack comes, we know our last Data
* has made it across and we send the next Data
* We complete the block associated with that,
* and if we are not done, we start the next read
*/
lock( stat ) {
StreamState sent = (StreamState)stat.PendingState;
bool finished = stat.CompleteBlock(block, sent.Size);
if( !finished ) {
//Do the next read:
StreamState rs = new StreamState();
int new_block = block + 1;
stat.StartBlock(new_block, rs);
rs.Stat = stat;
rs.Block = new_block;
rs.Data = new byte[ stat.Request.Blksize ];
rs.Offset = 0;
stat.Data.BeginRead(rs.Data, rs.Offset, stat.Request.Blksize,
new AsyncCallback(this.ReadHandler),
rs);
}
}
break;
case Opcode.Error:
Error.Code code = (Error.Code)NumberSerializer.ReadShort(packet_data);
string message = ReadAsciiStringFrom(packet_data);
//Things did not work out for us
stat.SetError(new Error(code, message));
break;
default:
err = new Error(Error.Code.IllegalOp, "Unknown Opcode");
throw new Exception();
}//End of switch
}//End of case where stat != null
}//End of case where TID is known
else {
//Never heard of this TID!
Error error = new Error(Error.Code.UnknownTID, "say what?");
AHPacket resp = CreateErrorPacket(p.Source, DefaultTID, peer_tid, error);
_node.Send(resp);
}
}
catch(Exception x) {
/**
* If there has been any Exception or Error, we will wind up here
* in which case we send an error response and release this TID.
*/
if( err == null ) {
//Set the error
err = new Error(Error.Code.NotDefined, x.ToString() );
}
SendError(req, err);
ReleaseTID(local_tid);
}
}
/**
* Implementing from IAHPacketHandler
*/
public bool HandlesAHProtocol(AHPacket.Protocol type) {
return (type == AHPacket.Protocol.Tftp);
}
/**
* Handle sending of an edge synchronization.
* @param e tunnel edge.
* @param forwarders list of forwarders for the tunnel edge.
*/
public void HandleSyncSend(Edge e, IEnumerable forwarders) {
if (0 == _running) {
//do nothing
return;
}
TunnelEdge tun_edge = (TunnelEdge)e;
Packet p = null;
using( MemoryStream ms = new MemoryStream() ) {
ms.WriteByte((byte) MessageType.EdgeSync);
NumberSerializer.WriteInt(tun_edge.ID, ms);
NumberSerializer.WriteInt(tun_edge.RemoteID, ms);
ArrayList args = new ArrayList();
foreach (Address addr in forwarders) {
//add forwarding addresses
args.Add( addr.ToMemBlock() );
}
AdrConverter.Serialize(args, ms);
p = new AHPacket(1, 2, _node.Address, tun_edge.Target,
AHPacket.AHOptions.Exact,
AHPacket.Protocol.Tunneling, ms.ToArray());
}
ArrayList packet_senders = tun_edge.PacketSenders;
int r_idx = _rand.Next(0, packet_senders.Count);
int attempts = packet_senders.Count;
while (attempts-- > 0) {
ISender sender = null;
try {
int this_idx = (r_idx + attempts) % packet_senders.Count;
sender = (ISender) packet_senders[this_idx];
#if TUNNEL_DEBUG
Console.Error.WriteLine("Sending edge sync on base connection: {0}",
_node.ConnectionTable.GetConnection((Edge) sender));
#endif
sender.Send(p);
return;
} catch(EdgeClosedException) {
/*
* Just ignore it an move on to the next sender
*/
} catch(SendException x) {
//Just ignore it an move on to the next sender
} catch(Exception ex) {
if(ProtocolLog.UdpEdge.Enabled)
ProtocolLog.Write(ProtocolLog.Exceptions, String.Format(
"Error sending edge sync on packet_sender: {0}, {1}", sender, ex));
}
}
}
/**
* Here we handle routing AHPackets
*/
public void HandleData(MemBlock data, ISender ret_path, object state) {
/*
* Unfortunately, the old code needs the full header intact, and
* we have already eaten a byte of it, put it back:
*/
MemBlock full_packet = data.ExtendHead(1);
AHPacket p = new AHPacket(full_packet);
//Route avoiding the edge we got the packet from:
IRouter router = null;
if( p.Destination.Class == 0 ) {
router = _ah_router;
}
else {
router = _d_router;
}
Edge edge_rec_from = ret_path as Edge;
bool deliver_locally;
router.Route(edge_rec_from, p, out deliver_locally);
if( deliver_locally ) {
//Send a response exactly back to the node that sent to us
ISender resp_send = new AHSender(_n, ret_path, p.Source,
_n.DefaultTTLFor(p.Source),
AHPacket.AHOptions.Exact);
//data:
_n.HandleData( data.Slice(AHPacket.HeaderLength), resp_send, this);
}
}
/**
* This method creates an instance of a tunnel edge to a remote node, given its
* tunnel transport URI.
* @param ta TransportAddress to create an edge to
* @param ecb the EdgeCreationCallback to call when done
* @throw EdgeException if we try to call this before calling
* Start.
*/
public override void CreateEdgeTo(TransportAddress ta, EdgeCreationCallback ecb)
{
try {
if (!IsStarted) {
throw new EdgeException("TunnelEdgeListener not started");
}
else if (0 == _running) {
throw new EdgeException("TunnelEdgeListener not running");
}
else if (ta.TransportAddressType != this.TAType) {
throw new EdgeException(ta.TransportAddressType.ToString()
+ " is not my type: " + this.TAType.ToString());
}
else {
#if TUNNEL_DEBUG
Console.Error.WriteLine("CreateEdgeTo TunnelEdge to: {0}", ta);
#endif
TunnelTransportAddress tun_ta = ta as TunnelTransportAddress;
ArrayList forwarders = new ArrayList();
ArrayList forwarding_edges = new ArrayList();
#if TUNNEL_DEBUG
Console.Error.WriteLine("TunnelEdgeListener: Finding structured connections to tunnel over");
#endif
IEnumerable struc_cons = _node.ConnectionTable.GetConnections(ConnectionType.Structured);
if (struc_cons == null) {
#if TUNNEL_DEBUG
Console.Error.WriteLine("List of structured connections is null");
#endif
}
#if TUNNEL_DEBUG
Console.Error.WriteLine("TunnelEdgeListener: Browsing list of structured connections");
#endif
foreach (Connection con in struc_cons) {
#if TUNNEL_DEBUG
Console.Error.WriteLine("TunnelEdgeListener: Testing : {0}", con.Address);
#endif
if (con.Edge.TAType == TransportAddress.TAType.Tunnel) {
#if TUNNEL_DEBUG
Console.Error.WriteLine("Cannot tunnel over tunnel: " + con.Address.ToString());
#endif
continue;
}
if (!tun_ta.ContainsForwarder(con.Address)) {
#if TUNNEL_DEBUG
Console.Error.WriteLine("Cannot tunnel over connection: " + con.Address.ToString());
#endif
continue;
}
#if TUNNEL_DEBUG
Console.Error.WriteLine("Can tunnel over connection: " + con.Address.ToString());
#endif
forwarders.Add(con.Address);
forwarding_edges.Add(con.Edge);
}
if (forwarders.Count < MIN_FORWARDERS) {
ecb(false, null, new EdgeException("Cannot create edge over TA: " + tun_ta + ", not many forwarders"));
return;
}
tun_ta = new TunnelTransportAddress(tun_ta.Target, forwarders);
//choose a locally unique id
lock( _sync ) {
//Get a random ID for this edge:
int localid;
int remoteid = 0;
do {
localid = _rand.Next();
//Make sure we don't have negative ids
if( localid < 0 ) { localid = ~localid; }
} while( _id_ht.Contains(localid) || localid == 0 );
//looks like the new edge is ready
TunnelEdge e = new TunnelEdge(this, false, _node, tun_ta.Target, forwarders, localid, remoteid);
#if TUNNEL_DEBUG
Console.Error.WriteLine("Creating an instance of TunnelEdge: {0}", e);
Console.Error.WriteLine("remoteid: {0}, localid: {1}", remoteid, localid);
#endif
_id_ht[localid] = e;
//we will defer the new edge event for later
//when we actually get a response
//now build the packet payload
Packet p = null;
using(MemoryStream ms = new MemoryStream()) {
ms.WriteByte((byte) MessageType.EdgeRequest);
NumberSerializer.WriteInt(localid, ms);
NumberSerializer.WriteInt(remoteid, ms);
#if TUNNEL_DEBUG
Console.Error.WriteLine("Written off type, localid, remoteid");
#endif
ArrayList args = new ArrayList();
//add the target address
byte[] addr_bytes = new byte[Address.MemSize];
_node.Address.CopyTo(addr_bytes);
args.Add(addr_bytes.Clone());
#if TUNNEL_DEBUG
Console.Error.WriteLine("Added target address");
#endif
foreach (Address fwd in forwarders) {
//add forwarding addresses
fwd.CopyTo(addr_bytes);
args.Add(addr_bytes.Clone());
#if TUNNEL_DEBUG
Console.Error.WriteLine("Added a forwarding address");
#endif
}
#if TUNNEL_DEBUG
Console.Error.WriteLine("Creating a memory stream holding the payload");
#endif
AdrConverter.Serialize(args, ms);
p = new AHPacket(1, 2, _node.Address, tun_ta.Target, AHPacket.AHOptions.Exact,
AHPacket.Protocol.Tunneling, ms.ToArray());
}
#if TUNNEL_DEBUG
Console.Error.WriteLine("Created a request packet.");
#endif
EdgeCreationState ecs = new EdgeCreationState(localid, forwarding_edges, p, ecb);
_ecs_ht[localid] = ecs;
#if TUNNEL_DEBUG
Console.Error.WriteLine("Created an edge creation state for the tunnel edge: {0}", e);
#endif
}
}
//we will defer this sending to next heartbeat; an artificial delay from out own side
} catch(Exception e) {
ecb(false, null, e);
}
}
/**
* When we get an EdgeRequest message, this is where we handle it.
* @param remoteid remote id for the edge.
* @param localid local id for the edge.
* @param rest_of_payload control message.
* @param return_path return path for the packet
*/
protected void HandleEdgeRequest(int remoteid, int localid, MemBlock rest_of_payload, ISender return_path)
{
#if TUNNEL_DEBUG
Console.Error.WriteLine("Receiving edge request");
#endif
//probably a new incoming edge
bool is_new_edge = true;
bool send_edge_event = false;
TunnelEdge e = null;
ArrayList args = (ArrayList) AdrConverter.Deserialize(rest_of_payload);
Address target = AddressParser.Parse(MemBlock.Reference((byte[]) args[0]));
//list of packet forwarders
ArrayList forwarders = new ArrayList();
for (int i = 1; i < args.Count; i++) {
forwarders.Add(AddressParser.Parse(MemBlock.Reference((byte[]) args[i])));
}
//it is however possible that we have already created the edge locally
lock( _sync ) {
TunnelEdge e_dup = (TunnelEdge) _remote_id_ht[remoteid];
if (e_dup != null) {
TunnelTransportAddress remote_ta = new TunnelTransportAddress(target, forwarders);
//compare TAs
TunnelTransportAddress e_rta = e_dup.RemoteTA as TunnelTransportAddress;
if (e_rta != null && e_rta.Target.Equals( remote_ta.Target ) ) {
//the fellow sent a duplicate edge request
is_new_edge = false;
#if TUNNEL_DEBUG
Console.Error.WriteLine("Duplicate edge request: from {0}", remote_ta);
#endif
//but do send a response back
//we also have to send a response back now
} else {
//someone else guessed the same id on its side
//still okay, we can generate a unqiue id locally
}
} else {
//this is the first edge request from a node and also
//has a unique id on its side
}
if(is_new_edge) {
do {
localid = _rand.Next();
//Make sure not to use negative ids
if( localid < 0 ) { localid = ~localid; }
} while( _id_ht.Contains(localid) || localid == 0 );
//create an edge
e = new TunnelEdge(this, true, _node, target, forwarders, localid, remoteid);
#if TUNNEL_DEBUG
Console.Error.WriteLine("Creating an instance of TunnelEdge: {0}", e);
Console.Error.WriteLine("remoteid: {0}, localid: {1}", remoteid, localid);
#endif
_id_ht[localid] = e;
_remote_id_ht[remoteid] = e;
try {
e.CloseEvent += this.CloseHandler;
}
catch {
CloseHandler(e, null);
throw;
}
#if TUNNEL_DEBUG
Console.Error.WriteLine("announcing tunnel edge (incoming): {0}", e);
#endif
send_edge_event = true;
}
}//Drop the lock
/*
* No matter what, we send a response back now
*/
Packet p = null;
using(MemoryStream ms = new MemoryStream()) {
ms.WriteByte((byte) MessageType.EdgeResponse);
NumberSerializer.WriteInt(localid, ms);
NumberSerializer.WriteInt(remoteid, ms);
//overwrite the first address in the edge response
args[0] = _node.Address.ToMemBlock();
AdrConverter.Serialize(args, ms);
p = new AHPacket(1, 2, _node.Address, target, AHPacket.AHOptions.Exact,
AHPacket.Protocol.Tunneling, ms.ToArray());
}
//send using the edge we received data on
#if TUNNEL_DEBUG
Console.Error.WriteLine("Sending edge response: {0}", p);
#endif
try {
AHSender ahs = (AHSender)return_path;
Edge from = (Edge)ahs.ReceivedFrom;
from.Send(p);
#if TUNNEL_DEBUG
} catch (Exception ex) {
Console.Error.WriteLine(ex);
#else
} catch (Exception) {
#endif
}
finally {
if( send_edge_event ) {
SendEdgeEvent(e);
}
}
}
static void Main(string[] args)
{
//log.Debug( "Starting the Brunet Echo Tester" );
String config_file = args[0];
NetworkConfiguration network_configuration = NetworkConfiguration.Deserialize(config_file);
int port_selection = Convert.ToInt32(args[1]); //There will be 10 different ports available for use: 0, 1, 2..
//for example, node 0 on a machine will use port_selection # 0, node 1 on a machine will use port_selection # 1
///There will be multiple BruNet nodes on the same machine. The following is a list of possible ports used
int list_size = 150;
int [] port_list = new int[list_size];
for(int i = 0; i < list_size; i++){
port_list[i] = 25000 + i;
}
///The line below is used when there is only one node per machine
//int local_host_index = network_configuration.GetLocalHostIndex();
int desired_port = port_list[port_selection];
int local_host_index = network_configuration.GetLocalHostIndex(desired_port);
NodeConfiguration this_node_configuration = (NodeConfiguration)network_configuration.Nodes[local_host_index];
TransportAddressConfiguration local_ta_configuration = (TransportAddressConfiguration)this_node_configuration.TransportAddresses[0];
short port = local_ta_configuration.Port;
SHA1 sha = new SHA1CryptoServiceProvider();
String local_ta = local_ta_configuration.GetTransportAddressURI();
//We take the local transport address plus the port number to be hashed to obtain a random AHAddress
byte[] hashedbytes = sha.ComputeHash(Encoding.UTF8.GetBytes(local_ta + port));
//inforce type 0
hashedbytes[Address.MemSize - 1] &= 0xFE;
AHAddress _local_ahaddress = new AHAddress(hashedbytes);
Node this_node = new StructuredNode( _local_ahaddress );
///Node this_node = new HybridNode( new AHAddress( new BigInteger( 2*(local_host_index+1) ) ) );
String file_string = "./data/brunetadd" + Convert.ToString(desired_port) + ".log";
StreamWriter sw = new StreamWriter(file_string, false);
sw.WriteLine( "local_address " + this_node.Address.ToBigInteger().ToString() + " " + Dns.GetHostName()
+ ":" + port);
sw.Close();
if ( local_ta_configuration.Protocol == "tcp" ) {
this_node.AddEdgeListener( new TcpEdgeListener(port) );
}
else if( local_ta_configuration.Protocol == "udp" ) {
this_node.AddEdgeListener( new UdpEdgeListener(port) );
}
int remote_node_index = local_host_index-1;
int num_remote_ta = 20; //20 nodes on the list to try to bootstrap to
if (local_host_index!=0) {
NodeConfiguration remote_node_configuration = (NodeConfiguration)network_configuration.Nodes[0];
TransportAddressConfiguration remote_ta_configuration = (TransportAddressConfiguration)remote_node_configuration.TransportAddresses[0];
String remote_ta = remote_ta_configuration.GetTransportAddressURI();
this_node.RemoteTAs.Add( TransportAddressFactory.CreateInstance( remote_ta ) );
}
while ( (remote_node_index>=0) && (num_remote_ta>=0) ) {
NodeConfiguration remote_node_configuration = (NodeConfiguration)network_configuration.Nodes[remote_node_index];
TransportAddressConfiguration remote_ta_configuration = (TransportAddressConfiguration)remote_node_configuration.TransportAddresses[0];
String remote_ta = remote_ta_configuration.GetTransportAddressURI();
this_node.RemoteTAs.Add( TransportAddressFactory.CreateInstance( remote_ta ) );
System.Console.WriteLine("Adding {0}", remote_ta);
remote_node_index--;
num_remote_ta--;
}
/* NodeConfiguration remote_node_configuration = (NodeConfiguration)network_configuration.Nodes[remote_node_index];
TransportAddressConfiguration remote_ta_configuration = (TransportAddressConfiguration)remote_node_configuration.TransportAddresses[0];
String remote_ta = remote_ta_configuration.GetTransportAddressURI();
this_node.RemoteTAs.Add( TransportAddressFactory.CreateInstance( remote_ta ) );*/
EchoTester echo_printer = new EchoTester();
this_node.GetTypeSource(PType.Protocol.Echo).Subscribe(echo_printer, this_node);
#if PLAB_LOG
///Initialize Brunet logger
BrunetLogger bl = new BrunetLogger(desired_port, (AHAddress)this_node.Address);
this_node.Logger = bl;
#endif
this_node.Connect();
//Send a "hello message" to a random neighbor
ASCIIEncoding ascii = new ASCIIEncoding();
//Make the target addresses
AHAddress target = new AHAddress( new BigInteger( 2*(remote_node_index+1) ) );
string hello_msg = "hello, brunet";
int byteCount = ascii.GetByteCount(hello_msg);
byte[] bytes = new byte[byteCount + 1];
ascii.GetBytes(hello_msg, 0, hello_msg.Length, bytes, 1);
// update the payload
// This is a request, so the first byte is greater than zero
bytes[0] = (byte) 1;
AHPacket p = new AHPacket(0, 30, this_node.Address,
target,
AHPacket.Protocol.Echo, bytes);
///RDP Experiment: sending the echo packet periodically
/* int seq = 0;
while(true){
int start_time = System.DateTime.Now.Millisecond;
this_node.Send(p);
Console.WriteLine("Seq = {0}, Start Time = {1}", seq, start_time);
System.Threading.Thread.Sleep(10000);
seq++;
}*/
///The following is a while-loop for the local node to Brunet-ping all other nodes in the network
System.Threading.Thread.Sleep(60000); ///IMPORTANT: change this parameter so we wait longer for larger network
Random uid_generator = new Random( DateTime.Now.Millisecond + local_ta.GetHashCode() + port);
bytes = new byte[5];
int target_index = 0, num_pings = 10, wait_time = 10000; //the wait_time is in ms
double ping_time;
PingWrapper pw = new PingWrapper();
while( target_index < network_configuration.Nodes.Count ){
if(target_index != local_host_index){///we do not ping the local machine
NodeConfiguration target_node_configuration = (NodeConfiguration)network_configuration.Nodes[target_index];
TransportAddressConfiguration target_ta_configuration = (TransportAddressConfiguration)target_node_configuration.TransportAddresses[0];
short target_port = target_ta_configuration.Port;
double ping1 = pw.Ping(target_ta_configuration.Address, 10000);
double ping2 = pw.Ping(target_ta_configuration.Address, 10000);
if(ping1 >= 0 || ping2 >= 0){ //we gather the data only when the node is ping-able
sha = new SHA1CryptoServiceProvider();
String target_ta = target_ta_configuration.GetTransportAddressURI();
//We take the transport address plus the port number to be hashed to obtain a random AHAddress
hashedbytes = sha.ComputeHash(Encoding.UTF8.GetBytes(target_ta + target_port));
//inforce type 0
hashedbytes[Address.MemSize - 1] &= 0xFE;
AHAddress _target_ahaddress = new AHAddress(hashedbytes);
#if PLAB_LOG
///Write the header to a log file
bl.LogBPHeader(local_ta_configuration.Address, local_ta_configuration.Port,
target_ta_configuration.Address, target_ta_configuration.Port);
bl.LogPingHeader(local_ta_configuration.Address, local_ta_configuration.Port,
target_ta_configuration.Address, target_ta_configuration.Port);
#endif
for(int i = 0; i < num_pings; i++){
//ping and Brunet-ping the target node for a number of times
int uid = uid_generator.Next(); //this is the unique id of the packet
// update the payload
// This is a request, so the first byte is greater than zero
bytes[0] = (byte) 1;
NumberSerializer.WriteInt(uid, bytes, 1);
p = new AHPacket(0, 30, this_node.Address, _target_ahaddress, AHPacket.Protocol.Echo, bytes);
this_node.Send(p);
ping_time = pw.Ping(target_ta_configuration.Address, wait_time); //wait wait_time number of ms
#if PLAB_LOG
bl.LogPing(ping_time);
#else
System.Console.WriteLine("Ping time: {0}",ping_time);
#endif
System.Threading.Thread.Sleep(wait_time);
}//end of for-loop
}
}//end of if-loop
target_index++;
}//end of while-loop
}
public void Test() {
/*
* Make some random packets and see if they round trip properly.
*/
RandomNumberGenerator rng = new RNGCryptoServiceProvider();
Random simple_rng = new Random();
for(int i = 0; i < 100; i++) {
AHAddress source = new AHAddress(rng);
AHAddress dest = new AHAddress(rng);
short ttl = (short)simple_rng.Next(Int16.MaxValue);
short hops = (short)simple_rng.Next(Int16.MaxValue);
ushort options = (ushort)simple_rng.Next(UInt16.MaxValue);
byte[] bin_prot = new byte[ simple_rng.Next(1,4) ];
simple_rng.NextBytes(bin_prot);
string random_prot = Base32.Encode( bin_prot );
byte[] payload = new byte[ simple_rng.Next(1,1024) ];
simple_rng.NextBytes(payload);
AHPacket p = new AHPacket(hops, ttl, source, dest,
options, random_prot, payload);
AssertEqualAHPackets(p, RoundTrip(p) );
AHPacket phops = new AHPacket((short)(hops + 1), ttl, source, dest,
options, random_prot, payload);
AHPacket inc_hops = p.IncrementHops();
AssertEqualAHPackets(phops, inc_hops );
//Round trip them all:
AssertEqualAHPackets(p, RoundTrip(p));
AssertEqualAHPackets(inc_hops, RoundTrip(inc_hops));
AssertEqualAHPackets(phops, RoundTrip(phops));
}
}
public AHPacket RoundTrip(AHPacket p) {
byte[] binary_packet = new byte[ p.Length ];
p.CopyTo( binary_packet, 0);
return new AHPacket(MemBlock.Reference(binary_packet));
}
public void AssertEqualAHPackets(AHPacket p1, AHPacket p2) {
Assert.AreEqual(p1.Hops, p2.Hops, "Hops");
Assert.AreEqual(p1.Ttl, p2.Ttl, "Ttl");
Assert.AreEqual(p1.Source, p2.Source, "Source");
Assert.AreEqual(p1.Destination, p2.Destination, "Dest");
Assert.AreEqual(p1.Options, p2.Options, "Options");
Assert.AreEqual(p1.PayloadType, p2.PayloadType, "Payload Type");
byte[] payload1 = p1.PayloadStream.ToArray();
byte[] payload2 = p2.PayloadStream.ToArray();
Assert.AreEqual(payload1.Length, payload2.Length, "Payload length");
for(int i = 0; i < payload1.Length; i++) {
Assert.AreEqual(payload1[i], payload2[i], "Payload[" + i.ToString() + "]");
}
Assert.AreEqual(p1.Length, p2.Length, "Total Length");
}
/**
* @returns a new AHPacket with the hops field incremented
*/
public AHPacket IncrementHops()
{
AHPacket p = new AHPacket();
p._buffer = _buffer;
p._hops = (short)(_hops + 1);
p._ttl = _ttl;
p._source = _source;
p._destination = _destination;
p._options = _options;
p._pt = _pt;
return p;
}
