Set up topic on sending

services/shhext/chat/protocol.go

@@ -89,13 +89,14 @@ func (p *ProtocolService) BuildDirectMessage(myIdentityKey *ecdsa.PrivateKey, pu
 	// across devices
 	var installationIDs []string
 	var sharedSecret []byte
+	var agreed bool
 	for installationID := range protocolMessage.GetDirectMessage() {
 		if installationID != noInstallationID {
 			installationIDs = append(installationIDs, installationID)
 		}
 	}
 	if len(installationIDs) != 0 {
-		sharedSecret, err = p.topic.Send(publicKey, installationIDs)
+		sharedSecret, agreed, err = p.topic.Send(myIdentityKey, p.encryption.config.InstallationID, publicKey, installationIDs)
 		if err != nil {
 			return nil, nil, err
 		}
@@ -106,7 +107,11 @@ func (p *ProtocolService) BuildDirectMessage(myIdentityKey *ecdsa.PrivateKey, pu
 		p.onNewTopicHandler([][]byte{sharedSecret})
 	}
 
-	return msg, sharedSecret, nil
+	if agreed {
+		return msg, sharedSecret, nil
+	} else {
+		return msg, nil, nil
+	}
 }
 
 // BuildDHMessage builds a message with DH encryption so that it can be decrypted by any other device.

services/shhext/chat/topic/service.go

@@ -17,9 +17,8 @@ func NewService(persistence PersistenceService) *Service {
 	return &Service{persistence: persistence}
 }
 
-// Receive will generate a shared secret for a given identity, and return it
-func (s *Service) Receive(myPrivateKey *ecdsa.PrivateKey, theirPublicKey *ecdsa.PublicKey, installationID string) ([]byte, error) {
-	log.Info("Receive called for", "installationID", installationID)
+func (s *Service) setupTopic(myPrivateKey *ecdsa.PrivateKey, theirPublicKey *ecdsa.PublicKey, installationID string) ([]byte, error) {
+	log.Info("Setup topic called for", "installationID", installationID)
 	sharedKey, err := ecies.ImportECDSA(myPrivateKey).GenerateShared(
 		ecies.ImportECDSAPublic(theirPublicKey),
 		sskLen,
@@ -37,22 +36,31 @@ func (s *Service) Receive(myPrivateKey *ecdsa.PrivateKey, theirPublicKey *ecdsa.
 	return sharedKey, err
 }
 
-// Send returns a shared key if we have received a message from all the installationIDs
-func (s *Service) Send(theirPublicKey *ecdsa.PublicKey, installationIDs []string) ([]byte, error) {
-	theirIdentity := crypto.CompressPubkey(theirPublicKey)
+// Receive will generate a shared secret for a given identity, and return it
+func (s *Service) Receive(myPrivateKey *ecdsa.PrivateKey, theirPublicKey *ecdsa.PublicKey, installationID string) ([]byte, error) {
+	return s.setupTopic(myPrivateKey, theirPublicKey, installationID)
+}
 
-	response, err := s.persistence.Get(theirIdentity, installationIDs)
+// Send returns a shared key and whether it has been acknowledged from all the installationIDs
+func (s *Service) Send(myPrivateKey *ecdsa.PrivateKey, myInstallationID string, theirPublicKey *ecdsa.PublicKey, theirInstallationIDs []string) ([]byte, bool, error) {
+	sharedKey, err := s.setupTopic(myPrivateKey, theirPublicKey, myInstallationID)
 	if err != nil {
-		return nil, err
+		return nil, false, err
+	}
+
+	theirIdentity := crypto.CompressPubkey(theirPublicKey)
+	response, err := s.persistence.Get(theirIdentity, theirInstallationIDs)
+	if err != nil {
+		return nil, false, err
 	}
 
-	for _, installationID := range installationIDs {
+	for _, installationID := range theirInstallationIDs {
 		if !response.installationIDs[installationID] {
-			return nil, nil
+			return sharedKey, false, nil
 		}
 	}
 
-	return response.secret, nil
+	return response.secret, true, nil
 }
 
 func (s *Service) All() ([][]byte, error) {

services/shhext/chat/topic/service_test.go

@@ -37,6 +37,7 @@ func (s *ServiceTestSuite) TearDownTest() {
 }
 
 func (s *ServiceTestSuite) TestSingleInstallationID() {
+	ourInstallationID := "our"
 	installationID1 := "1"
 	installationID2 := "2"
 
@@ -52,15 +53,17 @@ func (s *ServiceTestSuite) TestSingleInstallationID() {
 	s.Require().NotNil(sharedKey1, "it generates a shared key")
 
 	// We want to send a message to installationID1
-	sharedKey2, err := s.service.Send(&theirKey.PublicKey, []string{installationID1})
+	sharedKey2, agreed2, err := s.service.Send(myKey, ourInstallationID, &theirKey.PublicKey, []string{installationID1})
 	s.Require().NoError(err)
+	s.Require().True(agreed2)
 	s.Require().NotNil(sharedKey2, "We can retrieve a shared secret")
 	s.Require().Equal(sharedKey1, sharedKey2, "The shared secret is the same as the one stored")
 
 	// We want to send a message to multiple installationIDs, one of which we haven't never communicated with
-	sharedKey3, err := s.service.Send(&theirKey.PublicKey, []string{installationID1, installationID2})
+	sharedKey3, agreed3, err := s.service.Send(myKey, ourInstallationID, &theirKey.PublicKey, []string{installationID1, installationID2})
 	s.Require().NoError(err)
-	s.Require().Nil(sharedKey3, "No shared key is returned")
+	s.Require().NotNil(sharedKey3, "A shared key is returned")
+	s.Require().False(agreed3)
 
 	// We receive a message from installationID2
 	sharedKey4, err := s.service.Receive(myKey, &theirKey.PublicKey, installationID2)
@@ -69,9 +72,10 @@ func (s *ServiceTestSuite) TestSingleInstallationID() {
 	s.Require().Equal(sharedKey1, sharedKey4, "It generates the same key")
 
 	// We want to send a message to installationID 1 & 2, both have been
-	sharedKey5, err := s.service.Send(&theirKey.PublicKey, []string{installationID1, installationID2})
+	sharedKey5, agreed5, err := s.service.Send(myKey, ourInstallationID, &theirKey.PublicKey, []string{installationID1, installationID2})
 	s.Require().NoError(err)
 	s.Require().NotNil(sharedKey5, "We can retrieve a shared secret")
+	s.Require().True(agreed5)
 	s.Require().Equal(sharedKey1, sharedKey5, "The shared secret is the same as the one stored")
 
 }