1 files changed, 134 insertions, 0 deletions

diff --git a/src/gnunet/service/dht/service.go b/src/gnunet/service/dht/service.go
new file mode 100644
index 0000000..2a189bb
--- /dev/null
+++ b/src/gnunet/service/dht/service.go
@@ -0,0 +1,134 @@
+// This file is part of gnunet-go, a GNUnet-implementation in Golang.
+// Copyright (C) 2019, 2020 Bernd Fix  >Y<
+//
+// gnunet-go is free software: you can redistribute it and/or modify it
+// under the terms of the GNU Affero General Public License as published
+// by the Free Software Foundation, either version 3 of the License,
+// or (at your option) any later version.
+//
+// gnunet-go is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+//
+// SPDX-License-Identifier: AGPL3.0-or-later
+
+package dht
+
+import (
+        "context"
+        "fmt"
+        "io"
+
+        "gnunet/core"
+        "gnunet/message"
+        "gnunet/service"
+
+        "github.com/bfix/gospel/logger"
+)
+
+// Error codes
+var (
+        ErrInvalidID           = fmt.Errorf("invalid/unassociated ID")
+        ErrBlockExpired        = fmt.Errorf("block expired")
+        ErrInvalidResponseType = fmt.Errorf("invald response type")
+)
+
+//----------------------------------------------------------------------
+// "GNUnet R5N DHT" service implementation
+//----------------------------------------------------------------------
+
+// Service implements a DHT service
+type Service struct {
+        Module
+}
+
+// NewService creates a new DHT service instance
+func NewService(ctx context.Context, c *core.Core) service.Service {
+        return &Service{
+                Module: *NewModule(ctx, c),
+        }
+}
+
+// ServeClient processes a client channel.
+func (s *Service) ServeClient(ctx context.Context, id int, mc *service.Connection) {
+        reqID := 0
+        var cancel context.CancelFunc
+        ctx, cancel = context.WithCancel(ctx)
+
+loop:
+        for {
+                // receive next message from client
+                reqID++
+                logger.Printf(logger.DBG, "[dht:%d:%d] Waiting for client request...\n", id, reqID)
+                msg, err := mc.Receive(ctx)
+                if err != nil {
+                        if err == io.EOF {
+                                logger.Printf(logger.INFO, "[dht:%d:%d] Client channel closed.\n", id, reqID)
+                        } else if err == service.ErrConnectionInterrupted {
+                                logger.Printf(logger.INFO, "[dht:%d:%d] Service operation interrupted.\n", id, reqID)
+                        } else {
+                                logger.Printf(logger.ERROR, "[dht:%d:%d] Message-receive failed: %s\n", id, reqID, err.Error())
+                        }
+                        break loop
+                }
+                logger.Printf(logger.INFO, "[dht:%d:%d] Received request: %v\n", id, reqID, msg)
+
+                // handle message
+                s.HandleMessage(context.WithValue(ctx, "label", fmt.Sprintf(":%d:%d", id, reqID)), msg, mc)
+        }
+        // close client connection
+        mc.Close()
+
+        // cancel all tasks running for this session/connection
+        logger.Printf(logger.INFO, "[dht:%d] Start closing session...\n", id)
+        cancel()
+}
+
+// HandleMessage handles a DHT request/response message. If the transport channel
+// is nil, responses are send directly via the transport layer.
+func (s *Service) HandleMessage(ctx context.Context, msg message.Message, back service.Responder) bool {
+        // assemble log label
+        label := ""
+        if v := ctx.Value("label"); v != nil {
+                label = v.(string)
+        }
+        // process message
+        switch msg.(type) {
+        case *message.DHTClientPutMsg:
+                //----------------------------------------------------------
+                // DHT PUT
+                //----------------------------------------------------------
+
+        case *message.DHTClientGetMsg:
+                //----------------------------------------------------------
+                // DHT GET
+                //----------------------------------------------------------
+
+        case *message.DHTClientGetResultsKnownMsg:
+                //----------------------------------------------------------
+                // DHT GET-RESULTS-KNOWN
+                //----------------------------------------------------------
+
+        case *message.DHTClientGetStopMsg:
+                //----------------------------------------------------------
+                // DHT GET-STOP
+                //----------------------------------------------------------
+
+        case *message.DHTClientResultMsg:
+                //----------------------------------------------------------
+                // DHT RESULT
+                //----------------------------------------------------------
+
+        default:
+                //----------------------------------------------------------
+                // UNKNOWN message type received
+                //----------------------------------------------------------
+                logger.Printf(logger.ERROR, "[dht%s] Unhandled message of type (%d)\n", label, msg.Header().MsgType)
+                return false
+        }
+        return true
+}