/* * Send a packet by forwarding it first. */ public void Send(ICopyable d) { _sender.Send(new CopyList(_header, d)); }
/** * This handles the packet forwarding protocol */ public void HandleData(MemBlock b, ISender ret_path, object state) { /* * Check it */ AHSender ahs = ret_path as AHSender; if (ahs != null) { //This was an AHSender: /* * This goes A -> B -> C */ if (b[0] == 0) { int offset = 1; //This is the first leg, going from A->B Address add_c = AddressParser.Parse(b.Slice(offset, Address.MemSize)); offset += Address.MemSize; //Since ahs a sender to return, we would be the source: Address add_a = ahs.Destination; short ttl = NumberSerializer.ReadShort(b, offset); //2 bytes offset += 2; ushort options = (ushort)NumberSerializer.ReadShort(b, offset); //2 bytes offset += 2; MemBlock payload = b.Slice(offset); MemBlock f_header = MemBlock.Reference(new byte[] { 1 }); /* * switch the packet from [A B f0 C] to [B C f 1 A] */ ICopyable new_payload = new CopyList(PType.Protocol.Forwarding, f_header, add_a, payload); /* * ttl and options are present in the forwarding header. */ AHSender next = new AHSender(_n, ahs.ReceivedFrom, add_c, ttl, options); next.Send(new_payload); } else if (b[0] == 1) { /* * This is the second leg: B->C * Make a Forwarding Sender, and unwrap the inside packet */ Address add_a = AddressParser.Parse(b.Slice(1, Address.MemSize)); Address add_b = ahs.Destination; MemBlock rest_of_payload = b.Slice(1 + Address.MemSize); //Here's the return path: ISender new_ret_path = new ForwardingSender(_n, add_b, add_a); _n.HandleData(rest_of_payload, new_ret_path, this); } } else { //This is not (currently) supported. Console.Error.WriteLine("Got a forwarding request from: {0}", ret_path); } }
/** * This handles the packet forwarding protocol */ public void HandleData(MemBlock b, ISender ret_path, object state) { /* * Check it */ AHSender ahs = ret_path as AHSender; if( ahs != null ) { //This was an AHSender: /* * This goes A -> B -> C */ if( b[0] == 0 ) { int offset = 1; //This is the first leg, going from A->B Address add_c = AddressParser.Parse(b.Slice(offset, Address.MemSize)); offset += Address.MemSize; //Since ahs a sender to return, we would be the source: Address add_a = ahs.Destination; short ttl = NumberSerializer.ReadShort(b, offset);//2 bytes offset += 2; ushort options = (ushort) NumberSerializer.ReadShort(b, offset);//2 bytes offset += 2; MemBlock payload = b.Slice(offset); MemBlock f_header = MemBlock.Reference( new byte[]{1} ); /* * switch the packet from [A B f0 C] to [B C f 1 A] */ ICopyable new_payload = new CopyList(PType.Protocol.Forwarding, f_header, add_a, payload); /* * ttl and options are present in the forwarding header. */ AHSender next = new AHSender(_n, ahs.ReceivedFrom, add_c, ttl, options); next.Send(new_payload); } else if ( b[0] == 1 ) { /* * This is the second leg: B->C * Make a Forwarding Sender, and unwrap the inside packet */ Address add_a = AddressParser.Parse(b.Slice(1, Address.MemSize)); Address add_b = ahs.Destination; MemBlock rest_of_payload = b.Slice(1 + Address.MemSize); //Here's the return path: ISender new_ret_path = new ForwardingSender(_n, add_b, add_a); _n.HandleData(rest_of_payload, new_ret_path, this); } } else { //This is not (currently) supported. Console.Error.WriteLine("Got a forwarding request from: {0}", ret_path); } }