crypto: Clean up the method to check if a device is verified.

matrix_sdk/examples/emoji_verification.rs

@@ -58,7 +58,7 @@ async fn print_devices(user_id: &UserId, client: &Client) {
             "   {:<10} {:<30} {:<}",
             device.device_id(),
             device.display_name().as_deref().unwrap_or_default(),
-            device.is_trusted()
+            device.verified()
         );
     }
 }

matrix_sdk/src/client.rs

@@ -2251,7 +2251,7 @@ impl Client {
     ///     .unwrap()
     ///     .unwrap();
     ///
-    /// println!("{:?}", device.is_trusted());
+    /// println!("{:?}", device.verified());
     ///
     /// let verification = device.start_verification().await.unwrap();
     /// # });

matrix_sdk/src/device.rs

@@ -69,9 +69,10 @@ impl Device {
         Ok(SasVerification { inner: sas, client: self.client.clone() })
     }
 
-    /// Is the device trusted.
-    pub fn is_trusted(&self) -> bool {
-        self.inner.trust_state()
+    /// Is the device considered to be verified, either by locally trusting it
+    /// or using cross signing.
+    pub fn verified(&self) -> bool {
+        self.inner.verified()
     }
 
     /// Set the local trust state of the device to the given state.

matrix_sdk_crypto/src/identities/device.rs

@@ -145,9 +145,20 @@ impl Device {
         }
     }
 
-    /// Get the trust state of the device.
-    pub fn trust_state(&self) -> bool {
-        self.inner.trust_state(&self.own_identity, &self.device_owner_identity)
+    /// Is this device considered to be verified.
+    ///
+    /// This method returns true if either [`is_locally_trusted()`] returns true
+    /// or if [`is_cross_signing_trusted()`] returns true.
+    ///
+    /// [`is_locally_trusted()`]: #method.is_locally_trusted
+    /// [`is_cross_signing_trusted()`]: #method.is_cross_signing_trusted
+    pub fn verified(&self) -> bool {
+        self.inner.verified(&self.own_identity, &self.device_owner_identity)
+    }
+
+    /// Is this device considered to be verified using cross signing.
+    pub fn is_cross_signing_trusted(&self) -> bool {
+        self.inner.is_cross_signing_trusted(&self.own_identity, &self.device_owner_identity)
     }
 
     /// Set the local trust state of the device to the given state.
@@ -236,7 +247,7 @@ impl UserDevices {
     /// Returns true if there is at least one devices of this user that is
     /// considered to be verified, false otherwise.
     pub fn is_any_verified(&self) -> bool {
-        self.inner.values().any(|d| d.trust_state(&self.own_identity, &self.device_owner_identity))
+        self.inner.values().any(|d| d.verified(&self.own_identity, &self.device_owner_identity))
     }
 
     /// Iterator over all the device ids of the user devices.
@@ -340,7 +351,7 @@ impl ReadOnlyDevice {
     }
 
     /// Is the device locally marked as trusted.
-    pub fn is_trusted(&self) -> bool {
+    pub fn is_locally_trusted(&self) -> bool {
         self.local_trust_state() == LocalTrust::Verified
     }
 
@@ -369,46 +380,41 @@ impl ReadOnlyDevice {
         self.deleted.load(Ordering::Relaxed)
     }
 
-    pub(crate) fn trust_state(
+    pub(crate) fn verified(
         &self,
         own_identity: &Option<OwnUserIdentity>,
         device_owner: &Option<UserIdentities>,
     ) -> bool {
-        // TODO we want to return an enum mentioning if the trust is local, if
-        // only the identity is trusted, if the identity and the device are
-        // trusted.
-        if self.is_trusted() {
-            // If the device is locally marked as verified just return so, no
-            // need to check signatures.
-            true
-        } else {
-            own_identity.as_ref().map_or(false, |own_identity| {
-                // Our own identity needs to be marked as verified.
-                own_identity.is_verified()
-                    && device_owner
-                        .as_ref()
-                        .map(|device_identity| match device_identity {
-                            // If it's one of our own devices, just check that
-                            // we signed the device.
-                            UserIdentities::Own(_) => {
-                                own_identity.is_device_signed(self).map_or(false, |_| true)
-                            }
+        self.is_locally_trusted() || self.is_cross_signing_trusted(own_identity, device_owner)
+    }
 
-                            // If it's a device from someone else, first check
-                            // that our user has signed the other user and then
-                            // check if the other user has signed this device.
-                            UserIdentities::Other(device_identity) => {
-                                own_identity
-                                    .is_identity_signed(device_identity)
-                                    .map_or(false, |_| true)
-                                    && device_identity
-                                        .is_device_signed(self)
-                                        .map_or(false, |_| true)
-                            }
-                        })
-                        .unwrap_or(false)
-            })
-        }
+    pub(crate) fn is_cross_signing_trusted(
+        &self,
+        own_identity: &Option<OwnUserIdentity>,
+        device_owner: &Option<UserIdentities>,
+    ) -> bool {
+        own_identity.as_ref().map_or(false, |own_identity| {
+            // Our own identity needs to be marked as verified.
+            own_identity.is_verified()
+                && device_owner
+                    .as_ref()
+                    .map(|device_identity| match device_identity {
+                        // If it's one of our own devices, just check that
+                        // we signed the device.
+                        UserIdentities::Own(_) => {
+                            own_identity.is_device_signed(self).map_or(false, |_| true)
+                        }
+
+                        // If it's a device from someone else, first check
+                        // that our user has signed the other user and then
+                        // check if the other user has signed this device.
+                        UserIdentities::Other(device_identity) => {
+                            own_identity.is_identity_signed(device_identity).map_or(false, |_| true)
+                                && device_identity.is_device_signed(self).map_or(false, |_| true)
+                        }
+                    })
+                    .unwrap_or(false)
+        })
     }
 
     pub(crate) async fn encrypt(

matrix_sdk_crypto/src/identities/user.rs

@@ -784,15 +784,15 @@ pub(crate) mod test {
             device_owner_identity: Some(UserIdentities::Own(identity.clone())),
         };
 
-        assert!(!second.trust_state());
-        assert!(!second.is_trusted());
+        assert!(!second.is_locally_trusted());
+        assert!(!second.is_cross_signing_trusted());
 
-        assert!(!first.trust_state());
-        assert!(!first.is_trusted());
+        assert!(!first.is_locally_trusted());
+        assert!(!first.is_cross_signing_trusted());
 
         identity.mark_as_verified();
-        assert!(second.trust_state());
-        assert!(!first.trust_state());
+        assert!(second.verified());
+        assert!(!first.verified());
     }
 
     #[async_test]
@@ -821,12 +821,12 @@ pub(crate) mod test {
             device_owner_identity: Some(public_identity.clone().into()),
         };
 
-        assert!(!device.trust_state());
+        assert!(!device.verified());
 
         let mut device_keys = device.as_device_keys();
 
         identity.sign_device_keys(&mut device_keys).await.unwrap();
         device.inner.signatures = Arc::new(device_keys.signatures);
-        assert!(device.trust_state());
+        assert!(device.verified());
     }
 }

matrix_sdk_crypto/src/key_request.rs

@@ -479,7 +479,7 @@ impl KeyRequestMachine {
             .flatten();
 
         let own_device_check = || {
-            if device.trust_state() {
+            if device.verified() {
                 Ok(None)
             } else {
                 Err(KeyshareDecision::UntrustedDevice)

matrix_sdk_crypto/src/machine.rs

@@ -928,7 +928,7 @@ impl OlmMachine {
                     .unwrap_or(false)
             }) {
             if (self.user_id() == device.user_id() && self.device_id() == device.device_id())
-                || device.is_trusted()
+                || device.verified()
             {
                 VerificationState::Trusted
             } else {
@@ -1771,7 +1771,7 @@ pub(crate) mod test {
 
         let bob_device = alice.get_device(bob.user_id(), bob.device_id()).await.unwrap().unwrap();
 
-        assert!(!bob_device.is_trusted());
+        assert!(!bob_device.verified());
 
         let (alice_sas, request) = bob_device.start_verification().await.unwrap();
 
@@ -1834,14 +1834,14 @@ pub(crate) mod test {
             .unwrap();
 
         assert!(alice_sas.is_done());
-        assert!(bob_device.is_trusted());
+        assert!(bob_device.verified());
 
         let alice_device =
             bob.get_device(alice.user_id(), alice.device_id()).await.unwrap().unwrap();
 
-        assert!(!alice_device.is_trusted());
+        assert!(!alice_device.verified());
         bob.handle_verification_event(&event).await;
         assert!(bob_sas.is_done());
-        assert!(alice_device.is_trusted());
+        assert!(alice_device.verified());
     }
 }

matrix_sdk_crypto/src/verification/qrcode.rs

@@ -871,8 +871,8 @@ mod test {
 
             let identity = identity.own().unwrap();
 
-            assert!(!bob_device.is_trusted());
-            assert!(alice_device.is_trusted());
+            assert!(!bob_device.is_locally_trusted());
+            assert!(alice_device.is_locally_trusted());
             assert!(identity.is_verified());
         };