From 56cfa8f4f9d214dad02899ef6db11795a2da98b2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Damir=20Jeli=C4=87?= <poljar@termina.org.uk>
Date: Mon, 6 Feb 2023 16:00:24 +0100
Subject: [PATCH] fix(crypto): Always mark your own device as verified

---
 .../matrix-sdk-crypto-js/tests/device.test.js | 36 +++++++++++++++++--
 crates/matrix-sdk-crypto/src/machine.rs       | 17 +++++++--
 2 files changed, 49 insertions(+), 4 deletions(-)

diff --git a/bindings/matrix-sdk-crypto-js/tests/device.test.js b/bindings/matrix-sdk-crypto-js/tests/device.test.js
index 14ecc2051..ea6d3d6e9 100644
--- a/bindings/matrix-sdk-crypto-js/tests/device.test.js
+++ b/bindings/matrix-sdk-crypto-js/tests/device.test.js
@@ -69,7 +69,39 @@ describe(OlmMachine.name, () => {
 
     test('can read a user device', async () => {
         const m = await machine();
-        const dev = await m.getDevice(user, device);
+
+        const hypothetical_response = JSON.stringify({
+            "device_keys": {
+                "@alice:example.org": {
+                    "JLAFKJWSCS": {
+                        "algorithms": [
+                            "m.olm.v1.curve25519-aes-sha2",
+                            "m.megolm.v1.aes-sha2"
+                        ],
+                        "device_id": "JLAFKJWSCS",
+                        "keys": {
+                            "curve25519:JLAFKJWSCS": "wjLpTLRqbqBzLs63aYaEv2Boi6cFEbbM/sSRQ2oAKk4",
+                            "ed25519:JLAFKJWSCS": "nE6W2fCblxDcOFmeEtCHNl8/l8bXcu7GKyAswA4r3mM"
+                        },
+                        "signatures": {
+                            "@alice:example.org": {
+                                "ed25519:JLAFKJWSCS": "m53Wkbh2HXkc3vFApZvCrfXcX3AI51GsDHustMhKwlv3TuOJMj4wistcOTM8q2+e/Ro7rWFUb9ZfnNbwptSUBA"
+                            }
+                        },
+                        "unsigned": {
+                            "device_display_name": "Alice's mobile phone"
+                        },
+                        "user_id": "@alice:example.org"
+                    }
+                }
+            },
+            "failures": {}
+        });
+        // Insert another device into the store
+        await m.markRequestAsSent("ID", RequestType.KeysQuery, hypothetical_response);
+
+        const secondDeviceId = new DeviceId("JLAFKJWSCS");
+        const dev = await m.getDevice(user, secondDeviceId);
 
         expect(dev).toBeInstanceOf(Device);
         expect(dev.isVerified()).toStrictEqual(false);
@@ -82,7 +114,7 @@ describe(OlmMachine.name, () => {
         expect(dev.isLocallyTrusted()).toStrictEqual(true);
 
         expect(dev.userId.toString()).toStrictEqual(user.toString());
-        expect(dev.deviceId.toString()).toStrictEqual(device.toString());
+        expect(dev.deviceId.toString()).toStrictEqual(secondDeviceId.toString());
         expect(dev.deviceName).toBeUndefined();
 
         const deviceKey = dev.getKey(DeviceKeyAlgorithmName.Ed25519);
diff --git a/crates/matrix-sdk-crypto/src/machine.rs b/crates/matrix-sdk-crypto/src/machine.rs
index 215fd793b..be1ea7bd5 100644
--- a/crates/matrix-sdk-crypto/src/machine.rs
+++ b/crates/matrix-sdk-crypto/src/machine.rs
@@ -82,8 +82,8 @@ use crate::{
         Signatures,
     },
     verification::{Verification, VerificationMachine, VerificationRequest},
-    CrossSigningKeyExport, CryptoStoreError, ReadOnlyDevice, RoomKeyImportResult, SignatureError,
-    ToDeviceRequest,
+    CrossSigningKeyExport, CryptoStoreError, LocalTrust, ReadOnlyDevice, RoomKeyImportResult,
+    SignatureError, ToDeviceRequest,
 };
 
 /// State machine implementation of the Olm/Megolm encryption protocol used for
@@ -256,6 +256,11 @@ impl OlmMachine {
                 let account = ReadOnlyAccount::new(user_id, device_id);
                 let device = ReadOnlyDevice::from_account(&account).await;
 
+                // We just created this device from our own Olm `Account`. Since we are the
+                // owners of the private keys of this device we can safely mark
+                // the device as verified.
+                device.set_trust_state(LocalTrust::Verified);
+
                 Span::current()
                     .record("ed25519_key", display(account.identity_keys().ed25519))
                     .record("curve25519_key", display(account.identity_keys().curve25519));
@@ -1773,6 +1778,14 @@ pub(crate) mod tests {
     async fn create_olm_machine() {
         let machine = OlmMachine::new(user_id(), alice_device_id()).await;
         assert!(!machine.account().shared());
+
+        let own_device = machine
+            .get_device(machine.user_id(), machine.device_id(), None)
+            .await
+            .unwrap()
+            .expect("We should always have our own device in the store");
+
+        assert!(own_device.is_locally_trusted(), "Our own device should always be locally trusted");
     }
 
     #[async_test]