From b64fbdd1c1529d00788317872666c9e8d88d9a54 Mon Sep 17 00:00:00 2001
From: Jakob Borg <jakob@kastelo.net>
Date: Wed, 24 May 2023 12:34:17 +0200
Subject: [PATCH] wip

---
 lib/connections/service.go | 31 +++++++++++++------------------
 lib/connections/structs.go | 20 ++------------------
 2 files changed, 15 insertions(+), 36 deletions(-)

diff --git a/lib/connections/service.go b/lib/connections/service.go
index 8ec0816a7..f832c5685 100644
--- a/lib/connections/service.go
+++ b/lib/connections/service.go
@@ -172,8 +172,8 @@ type service struct {
 	listeners      map[string]genericListener
 	listenerTokens map[string]suture.ServiceToken
 
-	connectionsMut sync.Mutex
-	connections    map[protocol.DeviceID]int
+	numConnectionsMut sync.Mutex
+	numConnections    map[protocol.DeviceID]int
 }
 
 func NewService(cfg config.Wrapper, myID protocol.DeviceID, mdl Model, tlsCfg *tls.Config, discoverer discover.Finder, bepProtocolName string, tlsDefaultCommonName string, evLogger events.Logger, registry *registry.Registry, keyGen *protocol.KeyGenerator) Service {
@@ -206,8 +206,8 @@ func NewService(cfg config.Wrapper, myID protocol.DeviceID, mdl Model, tlsCfg *t
 		listeners:      make(map[string]genericListener),
 		listenerTokens: make(map[string]suture.ServiceToken),
 
-		connectionsMut: sync.NewMutex(),
-		connections:    make(map[protocol.DeviceID]int),
+		numConnectionsMut: sync.NewMutex(),
+		numConnections:    make(map[protocol.DeviceID]int),
 	}
 	cfg.Subscribe(service)
 
@@ -418,12 +418,7 @@ func (s *service) handleHellos(ctx context.Context) error {
 		// connections are limited.
 		rd, wr := s.limiter.getLimiters(remoteID, c, c.IsLocal())
 
-		// Amazing hack: We need to pass the connection to the model, but we
-		// also need to pass the model to the connection. The
-		// connectionContextModel handles the mediation by being constructed
-		// in two stages...
 		protoConn := protocol.NewConnection(remoteID, rd, wr, c, s.model, c, deviceCfg.Compression, s.cfg.FolderPasswords(remoteID), s.keyGen)
-
 		s.accountAddedConnection(remoteID)
 		go func() {
 			<-protoConn.Closed()
@@ -1198,21 +1193,21 @@ func (s *service) validateIdentity(c internalConn, expectedID protocol.DeviceID)
 }
 
 func (s *service) accountAddedConnection(d protocol.DeviceID) {
-	s.connectionsMut.Lock()
-	defer s.connectionsMut.Unlock()
-	s.connections[d]++
+	s.numConnectionsMut.Lock()
+	defer s.numConnectionsMut.Unlock()
+	s.numConnections[d]++
 }
 
 func (s *service) accountRemovedConnection(d protocol.DeviceID) {
-	s.connectionsMut.Lock()
-	defer s.connectionsMut.Unlock()
-	s.connections[d]--
+	s.numConnectionsMut.Lock()
+	defer s.numConnectionsMut.Unlock()
+	s.numConnections[d]--
 }
 
 func (s *service) connectionsForDevice(d protocol.DeviceID) int {
-	s.connectionsMut.Lock()
-	defer s.connectionsMut.Unlock()
-	return s.connections[d]
+	s.numConnectionsMut.Lock()
+	defer s.numConnectionsMut.Unlock()
+	return s.numConnections[d]
 }
 
 type nextDialRegistry map[protocol.DeviceID]nextDialDevice
diff --git a/lib/connections/structs.go b/lib/connections/structs.go
index 328eeac7b..c43bcf5d1 100644
--- a/lib/connections/structs.go
+++ b/lib/connections/structs.go
@@ -8,10 +8,7 @@ package connections
 
 import (
 	"context"
-	"crypto/sha256"
 	"crypto/tls"
-	"encoding/base32"
-	"encoding/binary"
 	"fmt"
 	"io"
 	"net"
@@ -92,26 +89,13 @@ func (t connType) Transport() string {
 }
 
 func newInternalConn(tc tlsConn, connType connType, isLocal bool, priority int) internalConn {
-	// Construct the connection ID. In principle it's an opaque string, but
-	// in practice it's the timestamp with added hash of connection details,
-	// meaning that 1) it's globally unique, and 2) it's sortable to
-	// determine a "primary" connection for a device. To ensure the
-	// sortability we use the base32 "hexencoding" which has the characters
-	// in the right order to sort lexicographically.
-	now := time.Now()
-	buf := binary.BigEndian.AppendUint64(nil, uint64(now.UnixNano()))
-	h := sha256.New()
-	fmt.Fprintf(h, "%v\n%v\n%v\n", connType, tc.LocalAddr(), tc.RemoteAddr())
-	buf = h.Sum(buf)
-	id := base32.HexEncoding.WithPadding(base32.NoPadding).EncodeToString(buf)
-
 	return internalConn{
 		tlsConn:       tc,
 		connType:      connType,
 		isLocal:       isLocal,
 		priority:      priority,
-		establishedAt: now.Truncate(time.Second),
-		connectionID:  id,
+		establishedAt: time.Now().Truncate(time.Second),
+		connectionID:  fmt.Sprintf("%v-%v-%v", tc.LocalAddr(), connType.Transport(), tc.RemoteAddr()),
 	}
 }