From 696b4a243f8015a8bb1fcd694fd51c61abdd44c7 Mon Sep 17 00:00:00 2001
From: RMidhunSuresh <hi@midhun.dev>
Date: Sun, 11 Jun 2023 20:35:39 +0530
Subject: [PATCH] Don't return if MSK is not trusted

---
 src/matrix/Session.js                   |  7 +------
 src/matrix/verification/CrossSigning.ts | 11 +++++++++--
 2 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/src/matrix/Session.js b/src/matrix/Session.js
index a3b7d06c..9db0bd7f 100644
--- a/src/matrix/Session.js
+++ b/src/matrix/Session.js
@@ -614,13 +614,8 @@ export class Session {
                     e2eeAccount: this._e2eeAccount,
                     deviceId: this.deviceId,
                 });
+                await crossSigning.load(log);
                 this._crossSigning.set(crossSigning);
-                // if (await crossSigning.load(log)) {
-                //     this._crossSigning.set(crossSigning);
-                // }
-                // else {
-                //     crossSigning.dispose();
-                // }
             });
         }
         await this._keyBackup.get()?.start(log);
diff --git a/src/matrix/verification/CrossSigning.ts b/src/matrix/verification/CrossSigning.ts
index 47677e94..9987db31 100644
--- a/src/matrix/verification/CrossSigning.ts
+++ b/src/matrix/verification/CrossSigning.ts
@@ -277,10 +277,17 @@ export class CrossSigning {
     async signDevice(verification: IVerificationMethod, log: ILogItem): Promise<DeviceKey | undefined> {
         return log.wrap("CrossSigning.signDevice", async log => {
             if (!this._isMasterKeyTrusted) {
+                /**
+                 * If we're the unverified device that is participating in
+                 * the verification process, it is expected that we do not
+                 * have access to the private part of MSK and thus
+                 * cannot determine if the MSK is trusted. In this case, we
+                 * do not need to sign anything because the other (verified)
+                 * device will sign our device key with the SSK.
+                 */
                 log.set("mskNotTrusted", true);
-                return;
             }
-            const shouldSign = await verification.verify();
+            const shouldSign = await verification.verify() && this._isMasterKeyTrusted;
             log.set("shouldSign", shouldSign);
             if (!shouldSign) {
                 return;