Merge pull request #335 from quotient-im/aa13q-e2ee-encrypted-msg

E2EE: introduce EncryptedEvent

5 files changed, 107 insertions, 11 deletions

diff --git a/lib/events/encryptedevent.cpp b/lib/events/encryptedevent.cpp
new file mode 100644
index 00000000..6942738a
--- /dev/null
+++ b/lib/events/encryptedevent.cpp
@@ -0,0 +1,29 @@
+#include "encryptedevent.h"
+#include "room.h"
+
+using namespace QMatrixClient;
+using namespace QtOlm;
+
+EncryptedEvent::EncryptedEvent(const QJsonObject &ciphertext, const QString &senderKey)
+    : RoomEvent(typeId(), matrixTypeId(),
+                { { AlgorithmKeyL , OlmV1Curve25519AesSha2AlgoKey },
+                  { CiphertextKeyL , ciphertext },
+                  { SenderKeyKeyL, senderKey }
+                })
+{ }
+
+EncryptedEvent::EncryptedEvent(QByteArray ciphertext, const QString &senderKey, const QString& deviceId, const QString& sessionId)
+    : RoomEvent(typeId(), matrixTypeId(),
+                { { AlgorithmKeyL , MegolmV1AesSha2AlgoKey },
+                  { CiphertextKeyL , QString(ciphertext) },
+                  { DeviceIdKeyL, deviceId },
+                  { SenderKeyKeyL, senderKey },
+                  { SessionIdKeyL, sessionId },
+                })
+{ }
+
+EncryptedEvent::EncryptedEvent(const QJsonObject &obj)
+    : RoomEvent(typeId(), obj)
+{
+    qCDebug(EVENTS) << "Encrypted event" << id();
+}
diff --git a/lib/events/encryptedevent.h b/lib/events/encryptedevent.h
new file mode 100644
index 00000000..2f9e4422
--- /dev/null
+++ b/lib/events/encryptedevent.h
@@ -0,0 +1,66 @@
+#pragma once
+
+#include "roomevent.h"
+#include "e2ee.h"
+
+namespace QMatrixClient
+{
+    class Room;
+    /*
+     * While the specification states:
+     *
+     * "This event type is used when sending encrypted events.
+     * It can be used either within a room
+     * (in which case it will have all of the Room Event fields),
+     * or as a to-device event."
+     * "The encrypted payload can contain any message event."
+     * https://matrix.org/docs/spec/client_server/latest#id493
+     *
+     * -- for most of the cases the message event is the room message event.
+     * And even for the to-device events the context is for the room.
+     *
+     * So, to simplify integration to the timeline, EncryptedEvent is a RoomEvent inheritor.
+     * Strictly speaking though, it's not always a RoomEvent, but an Event in general.
+     * It's possible, because RoomEvent interface is similar to Event's one
+     * and doesn't add new restrictions, just provides additional features.
+     */
+    class EncryptedEvent : public RoomEvent
+    {
+        Q_GADGET
+    public:
+        DEFINE_EVENT_TYPEID("m.room.encrypted", EncryptedEvent)
+
+        /* In case with Olm, the encrypted content of the event is
+         * a map from the recipient Curve25519 identity key to ciphertext information */
+        explicit EncryptedEvent(const QJsonObject& ciphertext,
+                                const QString& senderKey);
+        /* In case with Megolm, device_id and session_id are required */
+        explicit EncryptedEvent(QByteArray ciphertext,
+                                const QString& senderKey,
+                                const QString& deviceId,
+                                const QString& sessionId);
+        explicit EncryptedEvent(const QJsonObject& obj);
+
+        QString algorithm() const
+        {
+            QString algo = content<QString>(AlgorithmKeyL);
+            if (!SupportedAlgorithms.contains(algo)) {
+                qWarning(MAIN) << "The EncryptedEvent's algorithm" << algo
+                               << "is not supported";
+            }
+            return  algo;
+        }
+        QByteArray ciphertext() const { return content<QString>(CiphertextKeyL).toLatin1(); }
+        QJsonObject ciphertext(const QString& identityKey) const
+        {
+            return content<QJsonObject>(CiphertextKeyL).value(identityKey).toObject();
+        }
+        QString senderKey() const { return content<QString>(SenderKeyKeyL); }
+
+        /* device_id and session_id are required with Megolm */
+        QString deviceId() const { return content<QString>(DeviceIdKeyL); }
+        QString sessionId() const { return content<QString>(SessionIdKeyL); }
+    };
+    REGISTER_EVENT_TYPE(EncryptedEvent)
+
+}  // namespace QMatrixClient
diff --git a/lib/events/encryptionevent.cpp b/lib/events/encryptionevent.cpp
index b8e2b575..ee6c92b1 100644
--- a/lib/events/encryptionevent.cpp
+++ b/lib/events/encryptionevent.cpp
@@ -7,11 +7,12 @@
 
 #include "converters.h"
 #include "logging.h"
+#include "e2ee.h"
 
 #include <array>
 
 static const std::array<QString, 1> encryptionStrings = { {
-    QStringLiteral("m.megolm.v1.aes-sha2")
+    QMatrixClient::MegolmV1AesSha2AlgoKey
 } };
 
 namespace QMatrixClient {
@@ -36,9 +37,9 @@ using namespace QMatrixClient;
 
 EncryptionEventContent::EncryptionEventContent(const QJsonObject& json)
     : encryption(fromJson<EncryptionType>(json["algorithm"_ls]))
-    , algorithm(sanitized(json["algorithm"_ls].toString()))
-    , rotationPeriodMs(json["rotation_period_ms"_ls].toInt(604800000))
-    , rotationPeriodMsgs(json["rotation_period_msgs"_ls].toInt(100))
+    , algorithm(sanitized(json[AlgorithmKeyL].toString()))
+    , rotationPeriodMs(json[RotationPeriodMsKeyL].toInt(604800000))
+    , rotationPeriodMsgs(json[RotationPeriodMsgsKeyL].toInt(100))
 { }
 
 void EncryptionEventContent::fillJson(QJsonObject* o) const
@@ -47,7 +48,7 @@ void EncryptionEventContent::fillJson(QJsonObject* o) const
     Q_ASSERT_X(encryption != EncryptionType::Undefined, __FUNCTION__,
              "The key 'algorithm' must be explicit in EncryptionEventContent");
     if (encryption != EncryptionType::Undefined)
-        o->insert(QStringLiteral("algorithm"), algorithm);
-    o->insert(QStringLiteral("rotation_period_ms"), rotationPeriodMs);
-    o->insert(QStringLiteral("rotation_period_msgs"), rotationPeriodMsgs);
+        o->insert(AlgorithmKey, algorithm);
+    o->insert(RotationPeriodMsKey, rotationPeriodMs);
+    o->insert(RotationPeriodMsgsKey, rotationPeriodMsgs);
 }
diff --git a/lib/events/event.h b/lib/events/event.h
index b3a58806..6f28c4fa 100644
--- a/lib/events/event.h
+++ b/lib/events/event.h
@@ -62,6 +62,7 @@ namespace QMatrixClient
     static const auto UnsignedKey = QStringLiteral("unsigned");
     static const auto StateKeyKey = QStringLiteral("state_key");
     static const auto TypeKeyL = "type"_ls;
+    static const auto BodyKeyL = "body"_ls;
     static const auto ContentKeyL = "content"_ls;
     static const auto EventIdKeyL = "event_id"_ls;
     static const auto UnsignedKeyL = "unsigned"_ls;
diff --git a/lib/events/roommessageevent.cpp b/lib/events/roommessageevent.cpp
index 8f4e0ebc..ec18e962 100644
--- a/lib/events/roommessageevent.cpp
+++ b/lib/events/roommessageevent.cpp
@@ -32,7 +32,6 @@ using MsgType = RoomMessageEvent::MsgType;
 
 static const auto RelatesToKey = "m.relates_to"_ls;
 static const auto MsgTypeKey = "msgtype"_ls;
-static const auto BodyKey = "body"_ls;
 static const auto FormattedBodyKey = "formatted_body"_ls;
 
 static const auto TextTypeKey = "m.text";
@@ -159,7 +158,7 @@ RoomMessageEvent::RoomMessageEvent(const QJsonObject& obj)
     if (isRedacted())
         return;
     const QJsonObject content = contentJson();
-    if ( content.contains(MsgTypeKey) && content.contains(BodyKey) )
+    if ( content.contains(MsgTypeKey) && content.contains(BodyKeyL) )
     {
         auto msgtype = content[MsgTypeKey].toString();
         bool msgTypeFound = false;
@@ -196,7 +195,7 @@ QString RoomMessageEvent::rawMsgtype() const
 
 QString RoomMessageEvent::plainBody() const
 {
-    return contentJson()[BodyKey].toString();
+    return contentJson()[BodyKeyL].toString();
 }
 
 QMimeType RoomMessageEvent::mimeType() const
@@ -267,7 +266,7 @@ TextContent::TextContent(const QJsonObject& json)
         // Falling back to plain text, as there's no standard way to describe
         // rich text in messages.
         mimeType = PlainTextMimeType;
-        body = json[BodyKey].toString();
+        body = json[BodyKeyL].toString();
     }
     const auto replyJson = json[RelatesToKey].toObject()
                            .value(RelatesTo::ReplyTypeId()).toObject();