From 5c4229433661dfb2cddb4a502412797354b9f3d1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Damir=20Jeli=C4=87?= <poljar@termina.org.uk>
Date: Tue, 9 Jun 2020 13:53:27 +0200
Subject: [PATCH] EventIndex: Store and restore the encryption info for
 encrypted events.

---
 src/Searching.js           | 20 ++++++++++++++++++++
 src/indexing/EventIndex.js | 33 +++++++++++++++++++++++++++++----
 2 files changed, 49 insertions(+), 4 deletions(-)

diff --git a/src/Searching.js b/src/Searching.js
index 663328fe41..fb59cc563d 100644
--- a/src/Searching.js
+++ b/src/Searching.js
@@ -107,6 +107,26 @@ async function localSearch(searchTerm, roomId = undefined) {
     const result = MatrixClientPeg.get()._processRoomEventsSearch(
         emptyResult, response);
 
+    // Restore our encryption info so we can properly re-verify the events.
+    for (let i = 0; i < result.results.length; i++) {
+        const timeline = result.results[i].context.getTimeline();
+
+        for (let j = 0; j < timeline.length; j++) {
+            const ev = timeline[j];
+            if (ev.event.curve25519Key) {
+                ev.makeEncrypted(
+                    "m.room.encrypted",
+                    { algorithm: ev.event.algorithm },
+                    ev.event.curve25519Key,
+                    ev.event.ed25519Key,
+                );
+                ev._forwardingCurve25519KeyChain = ev.event.forwardingCurve25519KeyChain;
+
+                delete ev.event.curve25519Key;
+            }
+        }
+    }
+
     return result;
 }
 
diff --git a/src/indexing/EventIndex.js b/src/indexing/EventIndex.js
index fac7c92b65..d4e8ab0117 100644
--- a/src/indexing/EventIndex.js
+++ b/src/indexing/EventIndex.js
@@ -290,6 +290,33 @@ export default class EventIndex extends EventEmitter {
         return validEventType && validMsgType && hasContentValue;
     }
 
+    eventToJson(ev) {
+        const jsonEvent = ev.toJSON();
+        const e = ev.isEncrypted() ? jsonEvent.decrypted : jsonEvent;
+
+        if (ev.isEncrypted()) {
+            // Let us store some additional data so we can re-verify the event.
+            // The js-sdk checks if an event is encrypted using the algorithm,
+            // the sender key and ed25519 signing key are used to find the
+            // correct device that sent the event which allows us to check the
+            // verification state of the event, either directly or using cross
+            // signing.
+            e.curve25519Key = ev.getSenderKey();
+            e.ed25519Key = ev.getClaimedEd25519Key();
+            e.algorithm = ev.getWireContent().algorithm;
+            e.forwardingCurve25519KeyChain = ev.getForwardingCurve25519KeyChain();
+        } else {
+            // Make sure that unencrypted events don't contain any of that data,
+            // despite what the server might give to us.
+            delete e.curve25519Key;
+            delete e.ed25519Key;
+            delete e.algorithm;
+            delete e.forwardingCurve25519KeyChain;
+        }
+
+        return e;
+    }
+
     /**
      * Queue up live events to be added to the event index.
      *
@@ -300,8 +327,7 @@ export default class EventIndex extends EventEmitter {
 
         if (!this.isValidEvent(ev)) return;
 
-        const jsonEvent = ev.toJSON();
-        const e = ev.isEncrypted() ? jsonEvent.decrypted : jsonEvent;
+        const e = this.eventToJson(ev);
 
         const profile = {
             displayname: ev.sender.rawDisplayName,
@@ -477,8 +503,7 @@ export default class EventIndex extends EventEmitter {
             // Let us convert the events back into a format that EventIndex can
             // consume.
             const events = filteredEvents.map((ev) => {
-                const jsonEvent = ev.toJSON();
-                const e = ev.isEncrypted() ? jsonEvent.decrypted : jsonEvent;
+                const e = this.eventToJson(ev);
 
                 let profile = {};
                 if (e.sender in profiles) profile = profiles[e.sender];