Make e2ee optional

go.mod

@@ -21,7 +21,7 @@ require (
 	golang.org/x/net v0.0.0-20200324143707-d3edc9973b7e
 	gopkg.in/toast.v1 v1.0.0-20180812000517-0a84660828b2
 	gopkg.in/yaml.v2 v2.2.8
-	maunium.net/go/mautrix v0.2.0-beta.4.0.20200505163640-61b3fde37bf4
+	maunium.net/go/mautrix v0.2.0-beta.4.0.20200505170605-f82efbca9632
 	maunium.net/go/mauview v0.1.0
 	maunium.net/go/tcell v0.1.0
 )

go.sum

@@ -98,6 +98,8 @@ maunium.net/go/mautrix v0.2.0-beta.4.0.20200505161530-e9e56523da93 h1:kaf3m/X4Qc
 maunium.net/go/mautrix v0.2.0-beta.4.0.20200505161530-e9e56523da93/go.mod h1:SkGZzch8CvU2qKtNpYxtzZ0sQxfVEJ3IsVVLSUBUx9Y=
 maunium.net/go/mautrix v0.2.0-beta.4.0.20200505163640-61b3fde37bf4 h1:iGxePGtVVBYSni/GQpQHWMiISIFndJK3+GKajZJCSXo=
 maunium.net/go/mautrix v0.2.0-beta.4.0.20200505163640-61b3fde37bf4/go.mod h1:SkGZzch8CvU2qKtNpYxtzZ0sQxfVEJ3IsVVLSUBUx9Y=
+maunium.net/go/mautrix v0.2.0-beta.4.0.20200505170605-f82efbca9632 h1:oPTIlRE5S6QMmumnxV/fZREhwMKJcbMEj67J143EY+U=
+maunium.net/go/mautrix v0.2.0-beta.4.0.20200505170605-f82efbca9632/go.mod h1:SkGZzch8CvU2qKtNpYxtzZ0sQxfVEJ3IsVVLSUBUx9Y=
 maunium.net/go/mauview v0.1.0 h1:x2WdkKI2zdriJuPAB0CKlwmnHGE7W9xfM5z6RgG+IIg=
 maunium.net/go/mauview v0.1.0/go.mod h1:og9WbzmWe9SNYNyOFlCv8qa9zMcOvG2nzRJ5vYyud9U=
 maunium.net/go/tcell v0.1.0 h1:XzsEoGCvOw5nac+tlkSLzQcliLYTN4PrtA7ar2ptjSM=

matrix/crypto.go

@@ -0,0 +1,61 @@
+// gomuks - A terminal Matrix client written in Go.
+// Copyright (C) 2020 Tulir Asokan
+//
+// This program 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.
+//
+// This program 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 <https://www.gnu.org/licenses/>.
+
+// +build cgo
+
+package matrix
+
+import (
+	"path/filepath"
+
+	"maunium.net/go/gomuks/debug"
+	"maunium.net/go/mautrix/crypto"
+)
+
+type cryptoLogger struct{}
+
+func (c cryptoLogger) Error(message string, args ...interface{}) {
+	debug.Printf("[Crypto/Error] "+message, args...)
+}
+
+func (c cryptoLogger) Warn(message string, args ...interface{}) {
+	debug.Printf("[Crypto/Warn] "+message, args...)
+}
+
+func (c cryptoLogger) Debug(message string, args ...interface{}) {
+	debug.Printf("[Crypto/Debug] "+message, args...)
+}
+
+func (c cryptoLogger) Trace(message string, args ...interface{}) {
+	debug.Printf("[Crypto/Trace] "+message, args...)
+}
+
+func isBadEncryptError(err error) bool {
+	return err != crypto.SessionExpired && err != crypto.SessionNotShared && err != crypto.NoGroupSession
+}
+
+func (c *Container) initCrypto() error {
+	cryptoStore, err := crypto.NewGobStore(filepath.Join(c.config.DataDir, "crypto.gob"))
+	if err != nil {
+		return err
+	}
+	c.crypto = crypto.NewOlmMachine(c.client, cryptoLogger{}, cryptoStore, c.config.Rooms)
+	err = c.crypto.Load()
+	if err != nil {
+		return err
+	}
+	return nil
+}

matrix/matrix.go

@@ -36,7 +36,6 @@ import (
 	"github.com/pkg/errors"
 
 	"maunium.net/go/mautrix"
-	"maunium.net/go/mautrix/crypto"
 	"maunium.net/go/mautrix/crypto/attachment"
 	"maunium.net/go/mautrix/event"
 	"maunium.net/go/mautrix/format"
@@ -56,7 +55,7 @@ import (
 // It is used for all Matrix calls from the UI and Matrix event handlers.
 type Container struct {
 	client  *mautrix.Client
-	crypto  *crypto.OlmMachine
+	crypto  CryptoInterface
 	syncer  *GomuksSyncer
 	gmx     ifc.Gomuks
 	ui      ifc.GomuksUI
@@ -90,22 +89,14 @@ func (log mxLogger) Debugfln(message string, args ...interface{}) {
 	debug.Printf("[Matrix] "+message, args...)
 }
 
-type cryptoLogger struct{}
+type CryptoInterface interface {
-
+	Load() error
-func (c cryptoLogger) Error(message string, args ...interface{}) {
+	FlushStore() error
-	debug.Printf("[Crypto/Error] "+message, args...)
+	ProcessSyncResponse(resp *mautrix.RespSync, since string)
-}
+	HandleMemberEvent(*event.Event)
-
+	DecryptMegolmEvent(*event.Event) (*event.Event, error)
-func (c cryptoLogger) Warn(message string, args ...interface{}) {
+	EncryptMegolmEvent(id.RoomID, event.Type, event.Content) (*event.EncryptedEventContent, error)
-	debug.Printf("[Crypto/Warn] "+message, args...)
+	ShareGroupSession(id.RoomID, []id.UserID) error
-}
-
-func (c cryptoLogger) Debug(message string, args ...interface{}) {
-	debug.Printf("[Crypto/Debug] "+message, args...)
-}
-
-func (c cryptoLogger) Trace(message string, args ...interface{}) {
-	debug.Printf("[Crypto/Trace] "+message, args...)
 }
 
 // InitClient initializes the mautrix client and connects to the homeserver specified in the config.
@@ -135,12 +126,7 @@ func (c *Container) InitClient() error {
 	c.client.Logger = mxLogger{}
 	c.client.DeviceID = c.config.DeviceID
 
-	cryptoStore, err := crypto.NewGobStore(filepath.Join(c.config.DataDir, "crypto.gob"))
+	err = c.initCrypto()
-	if err != nil {
-		return err
-	}
-	c.crypto = crypto.NewOlmMachine(c.client, cryptoLogger{}, cryptoStore, c.config.Rooms)
-	err = c.crypto.Load()
 	if err != nil {
 		return err
 	}
@@ -300,12 +286,14 @@ func (c *Container) Stop() {
 			debug.Print("Error closing history manager:", err)
 		}
 		c.history = nil
+		if c.crypto != nil {
 			debug.Print("Flushing crypto store")
-		err = c.crypto.CryptoStore.Flush()
+			err = c.crypto.FlushStore()
 			if err != nil {
 				debug.Print("Error flushing crypto store:", err)
 			}
 		}
+	}
 }
 
 // UpdatePushRules fetches the push notification rules from the server and stores them in the current Session object.
@@ -355,12 +343,16 @@ func (c *Container) OnLogin() {
 
 	debug.Print("Initializing syncer")
 	c.syncer = NewGomuksSyncer(c.config.Rooms)
+	if c.crypto != nil {
 		c.syncer.OnSync(c.crypto.ProcessSyncResponse)
 		c.syncer.OnEventType(event.StateMember, func(source EventSource, evt *event.Event) {
 			c.crypto.HandleMemberEvent(evt)
 		})
-	c.syncer.OnEventType(event.EventMessage, c.HandleMessage)
 		c.syncer.OnEventType(event.EventEncrypted, c.HandleEncrypted)
+	} else {
+		c.syncer.OnEventType(event.EventEncrypted, c.HandleMessage)
+	}
+	c.syncer.OnEventType(event.EventMessage, c.HandleMessage)
 	c.syncer.OnEventType(event.EventSticker, c.HandleMessage)
 	c.syncer.OnEventType(event.EventReaction, c.HandleMessage)
 	c.syncer.OnEventType(event.EventRedaction, c.HandleRedaction)
@@ -564,6 +556,8 @@ func (c *Container) HandleEncrypted(source EventSource, mxEvent *event.Event) {
 	evt, err := c.crypto.DecryptMegolmEvent(mxEvent)
 	if err != nil {
 		debug.Print("Failed to decrypt event:", err)
+		// TODO add decryption failed message instead of passing through directly
+		c.HandleMessage(source, mxEvent)
 		return
 	}
 	c.HandleMessage(source, evt)
@@ -883,10 +877,10 @@ func (c *Container) SendEvent(evt *muksevt.Event) (id.EventID, error) {
 	_, _ = c.client.UserTyping(evt.RoomID, false, 0)
 	c.typing = 0
 	room := c.GetRoom(evt.RoomID)
-	if room != nil && room.Encrypted && evt.Type != event.EventReaction {
+	if room != nil && room.Encrypted && c.crypto != nil && evt.Type != event.EventReaction {
 		encrypted, err := c.crypto.EncryptMegolmEvent(evt.RoomID, evt.Type, evt.Content)
 		if err != nil {
-			if err != crypto.SessionExpired && err != crypto.SessionNotShared && err != crypto.NoGroupSession {
+			if isBadEncryptError(err) {
 				return "", err
 			}
 			debug.Print("Got", err, "while trying to encrypt message, sharing group session and trying again...")
@@ -1005,10 +999,11 @@ func (c *Container) GetHistory(room *rooms.Room, limit int) ([]*muksevt.Event, e
 			debug.Printf("Failed to unmarshal content of event %s (type %s) by %s in %s: %v\n%s", evt.ID, evt.Type.Repr(), evt.Sender, evt.RoomID, err, string(evt.Content.VeryRaw))
 		}
 
-		if evt.Type == event.EventEncrypted {
+		if c.crypto != nil && evt.Type == event.EventEncrypted {
 			decrypted, err := c.crypto.DecryptMegolmEvent(evt)
 			if err != nil {
 				debug.Print("Failed to decrypt event:", err)
+				// TODO add decryption failed message instead of passing through directly
 			} else {
 				resp.Chunk[i] = decrypted
 			}

matrix/nocrypto.go

@@ -0,0 +1,13 @@
+// This contains no-op stubs of the methods in crypto.go for non-cgo builds with crypto disabled.
+
+// +build !cgo
+
+package matrix
+
+func isBadEncryptError(err error) bool {
+	return false
+}
+
+func (c *Container) initCrypto() error {
+	return nil
+}

ui/messages/parser.go

@@ -82,7 +82,7 @@ func directParseEvent(matrix ifc.MatrixContainer, room *rooms.Room, evt *muksevt
 		}
 		return ParseMessage(matrix, room, evt, displayname)
 	case *event.EncryptedEventContent:
-		return NewExpandedTextMessage(evt, displayname, tstring.NewStyleTString("Encrypted messages are not yet supported", tcell.StyleDefault.Italic(true)))
+		return NewExpandedTextMessage(evt, displayname, tstring.NewStyleTString("Decryption failed or gomuks not built with encryption support", tcell.StyleDefault.Italic(true)))
 	case *event.TopicEventContent, *event.RoomNameEventContent, *event.CanonicalAliasEventContent:
 		return ParseStateEvent(evt, displayname)
 	case *event.MemberEventContent: