matrix-rust-sdk/matrix_sdk_crypto/src/device.rs

537 lines
17 KiB
Rust

// Copyright 2020 The Matrix.org Foundation C.I.C.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
use std::{
collections::BTreeMap,
convert::TryFrom,
ops::Deref,
sync::{
atomic::{AtomicBool, Ordering},
Arc,
},
};
use atomic::Atomic;
use matrix_sdk_common::{
api::r0::{
keys::SignedKey, to_device::send_event_to_device::IncomingRequest as OwnedToDeviceRequest,
},
encryption::DeviceKeys,
events::{room::encrypted::EncryptedEventContent, EventType},
identifiers::{DeviceId, DeviceKeyAlgorithm, DeviceKeyId, EventEncryptionAlgorithm, UserId},
};
use serde::{Deserialize, Serialize};
use serde_json::{json, Value};
use tracing::warn;
#[cfg(test)]
use super::{Account, OlmMachine};
use crate::{
error::{EventError, OlmError, OlmResult, SignatureError},
store::Result as StoreResult,
user_identity::{OwnUserIdentity, UserIdentities},
verification::VerificationMachine,
verify_json, ReadOnlyUserDevices, Sas,
};
/// A read-only version of a `Device`.
#[derive(Debug, Clone)]
pub struct ReadOnlyDevice {
user_id: Arc<UserId>,
device_id: Arc<Box<DeviceId>>,
algorithms: Arc<Vec<EventEncryptionAlgorithm>>,
keys: Arc<BTreeMap<DeviceKeyId, String>>,
signatures: Arc<BTreeMap<UserId, BTreeMap<DeviceKeyId, String>>>,
display_name: Arc<Option<String>>,
deleted: Arc<AtomicBool>,
trust_state: Arc<Atomic<LocalTrust>>,
}
#[derive(Debug, Clone)]
/// A device represents a E2EE capable client of an user.
pub struct Device {
pub(crate) inner: ReadOnlyDevice,
pub(crate) verification_machine: VerificationMachine,
pub(crate) own_identity: Option<OwnUserIdentity>,
pub(crate) device_owner_identity: Option<UserIdentities>,
}
impl Deref for Device {
type Target = ReadOnlyDevice;
fn deref(&self) -> &Self::Target {
&self.inner
}
}
impl Device {
/// Start a interactive verification with this `Device`
///
/// Returns a `Sas` object and to-device request that needs to be sent out.
pub async fn start_verification(&self) -> StoreResult<(Sas, OwnedToDeviceRequest)> {
self.verification_machine
.start_sas(self.inner.clone())
.await
}
/// Get the trust state of the device.
pub fn trust_state(&self) -> 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.inner.trust_state() == LocalTrust::Verified {
// If the device is localy marked as verified just return so, no
// need to check signatures.
true
} else {
self.own_identity.as_ref().map_or(false, |own_identity| {
// Our own identity needs to be marked as verified.
own_identity.is_verified()
&& self
.device_owner_identity
.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.inner)
.map_or(false, |_| true),
// If it's a device from someone else, first check
// that our user has signed the other user and then
// checkif 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.inner)
.map_or(false, |_| true)
}
})
.unwrap_or(false)
})
}
}
/// Set the local trust state of the device to the given state.
///
/// This won't affect any cross signing trust state, this only sets a flag
/// marking to have the given trust state.
///
/// # Arguments
///
/// * `trust_state` - The new trust state that should be set for the device.
pub async fn set_local_trust(&self, trust_state: LocalTrust) -> StoreResult<()> {
self.inner.set_trust_state(trust_state);
self.verification_machine
.store
.save_devices(&[self.inner.clone()])
.await
}
/// Encrypt the given content for this `Device`.
///
/// # Arguments
///
/// * `event_type` - The type of the event.
///
/// * `content` - The content of the event that should be encrypted.
pub(crate) async fn encrypt(
&self,
event_type: EventType,
content: Value,
) -> OlmResult<EncryptedEventContent> {
let sender_key = if let Some(k) = self.inner.get_key(DeviceKeyAlgorithm::Curve25519) {
k
} else {
warn!(
"Trying to encrypt a Megolm session for user {} on device {}, \
but the device doesn't have a curve25519 key",
self.user_id(),
self.device_id()
);
return Err(EventError::MissingSenderKey.into());
};
let mut session = if let Some(s) = self
.verification_machine
.store
.get_sessions(sender_key)
.await?
{
let session = &s.lock().await[0];
session.clone()
} else {
warn!(
"Trying to encrypt a Megolm session for user {} on device {}, \
but no Olm session is found",
self.user_id(),
self.device_id()
);
return Err(OlmError::MissingSession);
};
let message = session.encrypt(&self.inner, event_type, content).await;
self.verification_machine
.store
.save_sessions(&[session])
.await?;
message
}
}
/// A read only view over all devices belonging to a user.
#[derive(Debug)]
pub struct UserDevices {
pub(crate) inner: ReadOnlyUserDevices,
pub(crate) verification_machine: VerificationMachine,
pub(crate) own_identity: Option<OwnUserIdentity>,
pub(crate) device_owner_identity: Option<UserIdentities>,
}
impl UserDevices {
/// Get the specific device with the given device id.
pub fn get(&self, device_id: &DeviceId) -> Option<Device> {
self.inner.get(device_id).map(|d| Device {
inner: d,
verification_machine: self.verification_machine.clone(),
own_identity: self.own_identity.clone(),
device_owner_identity: self.device_owner_identity.clone(),
})
}
/// Iterator over all the device ids of the user devices.
pub fn keys(&self) -> impl Iterator<Item = &DeviceId> {
self.inner.keys()
}
/// Iterator over all the devices of the user devices.
pub fn devices(&self) -> impl Iterator<Item = Device> + '_ {
self.inner.devices().map(move |d| Device {
inner: d.clone(),
verification_machine: self.verification_machine.clone(),
own_identity: self.own_identity.clone(),
device_owner_identity: self.device_owner_identity.clone(),
})
}
}
#[derive(Debug, Clone, Copy, PartialEq, Serialize, Deserialize)]
/// The local trust state of a device.
pub enum LocalTrust {
/// The device has been verified and is trusted.
Verified = 0,
/// The device been blacklisted from communicating.
BlackListed = 1,
/// The trust state of the device is being ignored.
Ignored = 2,
/// The trust state is unset.
Unset = 3,
}
impl From<i64> for LocalTrust {
fn from(state: i64) -> Self {
match state {
0 => LocalTrust::Verified,
1 => LocalTrust::BlackListed,
2 => LocalTrust::Ignored,
3 => LocalTrust::Unset,
_ => LocalTrust::Unset,
}
}
}
impl ReadOnlyDevice {
/// Create a new Device.
pub fn new(
user_id: UserId,
device_id: Box<DeviceId>,
display_name: Option<String>,
trust_state: LocalTrust,
algorithms: Vec<EventEncryptionAlgorithm>,
keys: BTreeMap<DeviceKeyId, String>,
signatures: BTreeMap<UserId, BTreeMap<DeviceKeyId, String>>,
) -> Self {
Self {
user_id: Arc::new(user_id),
device_id: Arc::new(device_id),
display_name: Arc::new(display_name),
trust_state: Arc::new(Atomic::new(trust_state)),
signatures: Arc::new(signatures),
algorithms: Arc::new(algorithms),
keys: Arc::new(keys),
deleted: Arc::new(AtomicBool::new(false)),
}
}
/// The user id of the device owner.
pub fn user_id(&self) -> &UserId {
&self.user_id
}
/// The unique ID of the device.
pub fn device_id(&self) -> &DeviceId {
&self.device_id
}
/// Get the human readable name of the device.
pub fn display_name(&self) -> &Option<String> {
&self.display_name
}
/// Get the key of the given key algorithm belonging to this device.
pub fn get_key(&self, algorithm: DeviceKeyAlgorithm) -> Option<&String> {
self.keys
.get(&DeviceKeyId::from_parts(algorithm, &self.device_id))
}
/// Get a map containing all the device keys.
pub fn keys(&self) -> &BTreeMap<DeviceKeyId, String> {
&self.keys
}
/// Get a map containing all the device signatures.
pub fn signatures(&self) -> &BTreeMap<UserId, BTreeMap<DeviceKeyId, String>> {
&self.signatures
}
/// Get the trust state of the device.
pub fn trust_state(&self) -> LocalTrust {
self.trust_state.load(Ordering::Relaxed)
}
/// Is the device locally marked as trusted.
pub fn is_trusted(&self) -> bool {
self.trust_state() == LocalTrust::Verified
}
/// Is the device locally marked as blacklisted.
///
/// Blacklisted devices won't receive any group sessions.
pub fn is_blacklisted(&self) -> bool {
self.trust_state() == LocalTrust::BlackListed
}
/// Set the trust state of the device to the given state.
///
/// Note: This should only done in the cryptostore where the trust state can
/// be stored.
pub(crate) fn set_trust_state(&self, state: LocalTrust) {
self.trust_state.store(state, Ordering::Relaxed)
}
/// Get the list of algorithms this device supports.
pub fn algorithms(&self) -> &[EventEncryptionAlgorithm] {
&self.algorithms
}
/// Is the device deleted.
pub fn deleted(&self) -> bool {
self.deleted.load(Ordering::Relaxed)
}
/// Update a device with a new device keys struct.
pub(crate) fn update_device(&mut self, device_keys: &DeviceKeys) -> Result<(), SignatureError> {
self.verify_device_keys(device_keys)?;
let display_name = Arc::new(device_keys.unsigned.device_display_name.clone());
self.algorithms = Arc::new(device_keys.algorithms.clone());
self.keys = Arc::new(device_keys.keys.clone());
self.signatures = Arc::new(device_keys.signatures.clone());
self.display_name = display_name;
Ok(())
}
fn is_signed_by_device(&self, json: &mut Value) -> Result<(), SignatureError> {
let signing_key = self
.get_key(DeviceKeyAlgorithm::Ed25519)
.ok_or(SignatureError::MissingSigningKey)?;
verify_json(
&self.user_id,
&DeviceKeyId::from_parts(DeviceKeyAlgorithm::Ed25519, self.device_id()),
signing_key,
json,
)
}
pub(crate) fn as_signature_message(&self) -> Value {
json!({
"user_id": &*self.user_id,
"device_id": &*self.device_id,
"keys": &*self.keys,
"algorithms": &*self.algorithms,
"signatures": &*self.signatures,
})
}
pub(crate) fn verify_device_keys(
&self,
device_keys: &DeviceKeys,
) -> Result<(), SignatureError> {
self.is_signed_by_device(&mut json!(&device_keys))
}
pub(crate) fn verify_one_time_key(
&self,
one_time_key: &SignedKey,
) -> Result<(), SignatureError> {
self.is_signed_by_device(&mut json!(&one_time_key))
}
/// Mark the device as deleted.
pub(crate) fn mark_as_deleted(&self) {
self.deleted.store(true, Ordering::Relaxed);
}
#[cfg(test)]
pub async fn from_machine(machine: &OlmMachine) -> ReadOnlyDevice {
ReadOnlyDevice::from_account(machine.account()).await
}
#[cfg(test)]
pub async fn from_account(account: &Account) -> ReadOnlyDevice {
let device_keys = account.device_keys().await;
ReadOnlyDevice::try_from(&device_keys).unwrap()
}
}
impl TryFrom<&DeviceKeys> for ReadOnlyDevice {
type Error = SignatureError;
fn try_from(device_keys: &DeviceKeys) -> Result<Self, Self::Error> {
let device = Self {
user_id: Arc::new(device_keys.user_id.clone()),
device_id: Arc::new(device_keys.device_id.clone()),
algorithms: Arc::new(device_keys.algorithms.clone()),
signatures: Arc::new(device_keys.signatures.clone()),
keys: Arc::new(device_keys.keys.clone()),
display_name: Arc::new(device_keys.unsigned.device_display_name.clone()),
deleted: Arc::new(AtomicBool::new(false)),
trust_state: Arc::new(Atomic::new(LocalTrust::Unset)),
};
device.verify_device_keys(device_keys)?;
Ok(device)
}
}
impl PartialEq for ReadOnlyDevice {
fn eq(&self, other: &Self) -> bool {
self.user_id() == other.user_id() && self.device_id() == other.device_id()
}
}
#[cfg(test)]
pub(crate) mod test {
use serde_json::json;
use std::convert::TryFrom;
use crate::device::{LocalTrust, ReadOnlyDevice};
use matrix_sdk_common::{
encryption::DeviceKeys,
identifiers::{user_id, DeviceKeyAlgorithm},
};
fn device_keys() -> DeviceKeys {
let device_keys = json!({
"algorithms": vec![
"m.olm.v1.curve25519-aes-sha2",
"m.megolm.v1.aes-sha2"
],
"device_id": "BNYQQWUMXO",
"user_id": "@example:localhost",
"keys": {
"curve25519:BNYQQWUMXO": "xfgbLIC5WAl1OIkpOzoxpCe8FsRDT6nch7NQsOb15nc",
"ed25519:BNYQQWUMXO": "2/5LWJMow5zhJqakV88SIc7q/1pa8fmkfgAzx72w9G4"
},
"signatures": {
"@example:localhost": {
"ed25519:BNYQQWUMXO": "kTwMrbsLJJM/uFGOj/oqlCaRuw7i9p/6eGrTlXjo8UJMCFAetoyWzoMcF35vSe4S6FTx8RJmqX6rM7ep53MHDQ"
}
},
"unsigned": {
"device_display_name": "Alice's mobile phone"
}
});
serde_json::from_value(device_keys).unwrap()
}
pub(crate) fn get_device() -> ReadOnlyDevice {
let device_keys = device_keys();
ReadOnlyDevice::try_from(&device_keys).unwrap()
}
#[test]
fn create_a_device() {
let user_id = user_id!("@example:localhost");
let device_id = "BNYQQWUMXO";
let device = get_device();
assert_eq!(&user_id, device.user_id());
assert_eq!(device_id, device.device_id());
assert_eq!(device.algorithms.len(), 2);
assert_eq!(LocalTrust::Unset, device.trust_state());
assert_eq!(
"Alice's mobile phone",
device.display_name().as_ref().unwrap()
);
assert_eq!(
device.get_key(DeviceKeyAlgorithm::Curve25519).unwrap(),
"xfgbLIC5WAl1OIkpOzoxpCe8FsRDT6nch7NQsOb15nc"
);
assert_eq!(
device.get_key(DeviceKeyAlgorithm::Ed25519).unwrap(),
"2/5LWJMow5zhJqakV88SIc7q/1pa8fmkfgAzx72w9G4"
);
}
#[test]
fn update_a_device() {
let mut device = get_device();
assert_eq!(
"Alice's mobile phone",
device.display_name().as_ref().unwrap()
);
let display_name = "Alice's work computer".to_owned();
let mut device_keys = device_keys();
device_keys.unsigned.device_display_name = Some(display_name.clone());
device.update_device(&device_keys).unwrap();
assert_eq!(&display_name, device.display_name().as_ref().unwrap());
}
#[test]
fn delete_a_device() {
let device = get_device();
assert!(!device.deleted());
let device_clone = device.clone();
device.mark_as_deleted();
assert!(device.deleted());
assert!(device_clone.deleted());
}
}