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// 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.
mod helpers;
mod inner_sas;
mod sas_state;
use std::sync::Arc;
use as_variant::as_variant;
use eyeball::{ObservableWriteGuard, SharedObservable};
use futures_core::Stream;
use futures_util::StreamExt;
use inner_sas::InnerSas;
use ruma::{
api::client::keys::upload_signatures::v3::Request as SignatureUploadRequest,
events::{
key::verification::{cancel::CancelCode, start::SasV1Content, ShortAuthenticationString},
AnyMessageLikeEventContent, AnyToDeviceEventContent,
},
DeviceId, OwnedEventId, OwnedRoomId, OwnedTransactionId, RoomId, TransactionId, UserId,
};
pub use sas_state::AcceptedProtocols;
use tracing::{debug, error, trace};
use super::{
cache::RequestInfo,
event_enums::{AnyVerificationContent, OutgoingContent, OwnedAcceptContent, StartContent},
requests::RequestHandle,
CancelInfo, FlowId, IdentitiesBeingVerified, VerificationResult,
};
use crate::{
identities::{DeviceData, UserIdentityData},
olm::StaticAccountData,
requests::{OutgoingVerificationRequest, RoomMessageRequest},
store::CryptoStoreError,
Emoji, ToDeviceRequest,
};
/// Short authentication string object.
#[derive(Clone, Debug)]
pub struct Sas {
inner: SharedObservable<InnerSas>,
account: StaticAccountData,
identities_being_verified: IdentitiesBeingVerified,
flow_id: Arc<FlowId>,
we_started: bool,
request_handle: Option<RequestHandle>,
}
#[derive(Debug, Clone, Copy)]
enum State {
Created,
Started,
Accepted,
WeAccepted,
KeyReceived,
KeySent,
KeysExchanged,
Confirmed,
MacReceived,
WaitingForDone,
Done,
Cancelled,
}
impl From<&InnerSas> for State {
fn from(value: &InnerSas) -> Self {
match value {
InnerSas::Created(_) => Self::Created,
InnerSas::Started(_) => Self::Started,
InnerSas::Accepted(_) => Self::Accepted,
InnerSas::WeAccepted(_) => Self::WeAccepted,
InnerSas::KeyReceived(_) => Self::KeyReceived,
InnerSas::KeySent(_) => Self::KeySent,
InnerSas::KeysExchanged(_) => Self::KeysExchanged,
InnerSas::Confirmed(_) => Self::Confirmed,
InnerSas::MacReceived(_) => Self::MacReceived,
InnerSas::WaitingForDone(_) => Self::WaitingForDone,
InnerSas::Done(_) => Self::Done,
InnerSas::Cancelled(_) => Self::Cancelled,
}
}
}
/// The short auth string for the emoji method of SAS verification.
#[derive(Debug, Clone)]
pub struct EmojiShortAuthString {
/// A list of seven indices that should be used for the SAS verification.
///
/// The indices can be put into the emoji table in the [spec] to figure out
/// the symbols and descriptions.
///
/// If you have a table of [translated descriptions] for the emojis you will
/// want to use this field.
///
/// [spec]: https://spec.matrix.org/unstable/client-server-api/#sas-method-emoji
/// [translated descriptions]: https://github.com/matrix-org/matrix-doc/blob/master/data-definitions/
pub indices: [u8; 7],
/// A list of seven emojis that should be used for the SAS verification.
pub emojis: [Emoji; 7],
}
/// An Enum describing the state the SAS verification is in.
#[derive(Debug, Clone)]
pub enum SasState {
/// The verification has been created, the protocols that should be used
/// have been proposed to the other party.
Created {
/// The protocols that were proposed in the `m.key.verification.start`
/// event.
protocols: SasV1Content,
},
/// The verification has been started, the other party proposed the
/// protocols that should be used and that can be accepted.
Started {
/// The protocols that were proposed in the `m.key.verification.start`
/// event.
protocols: SasV1Content,
},
/// The verification has been accepted and both sides agreed to a set of
/// protocols that will be used for the verification process.
Accepted {
/// The protocols that were accepted in the `m.key.verification.accept`
/// event.
accepted_protocols: AcceptedProtocols,
},
/// The public keys have been exchanged and the short auth string can be
/// presented to the user.
KeysExchanged {
/// The emojis that represent the short auth string, will be `None` if
/// the emoji SAS method wasn't part of the [`AcceptedProtocols`].
emojis: Option<EmojiShortAuthString>,
/// The list of decimals that represent the short auth string.
decimals: (u16, u16, u16),
},
/// The verification process has been confirmed from our side, we're waiting
/// for the other side to confirm as well.
Confirmed,
/// The verification process has been successfully concluded.
Done {
/// The list of devices that has been verified.
verified_devices: Vec<DeviceData>,
/// The list of user identities that has been verified.
verified_identities: Vec<UserIdentityData>,
},
/// The verification process has been cancelled.
Cancelled(CancelInfo),
}
impl PartialEq for SasState {
fn eq(&self, other: &Self) -> bool {
matches!(
(self, other),
(Self::Created { .. }, Self::Created { .. })
| (Self::Started { .. }, Self::Started { .. })
| (Self::Accepted { .. }, Self::Accepted { .. })
| (Self::KeysExchanged { .. }, Self::KeysExchanged { .. })
| (Self::Confirmed, Self::Confirmed)
| (Self::Done { .. }, Self::Done { .. })
| (Self::Cancelled(_), Self::Cancelled(_))
)
}
}
impl From<&InnerSas> for SasState {
fn from(value: &InnerSas) -> Self {
match value {
InnerSas::Created(s) => {
Self::Created { protocols: s.state.protocol_definitions.to_owned() }
}
InnerSas::Started(s) => {
Self::Started { protocols: s.state.protocol_definitions.to_owned() }
}
InnerSas::Accepted(s) => {
Self::Accepted { accepted_protocols: s.state.accepted_protocols.to_owned() }
}
InnerSas::WeAccepted(s) => {
Self::Accepted { accepted_protocols: s.state.accepted_protocols.to_owned() }
}
InnerSas::KeySent(s) => {
Self::Accepted { accepted_protocols: s.state.accepted_protocols.to_owned() }
}
InnerSas::KeyReceived(s) => {
Self::Accepted { accepted_protocols: s.state.accepted_protocols.to_owned() }
}
InnerSas::KeysExchanged(s) => {
let emojis = value.supports_emoji().then(|| {
let emojis = s.get_emoji();
let indices = s.get_emoji_index();
EmojiShortAuthString { emojis, indices }
});
let decimals = s.get_decimal();
Self::KeysExchanged { emojis, decimals }
}
InnerSas::MacReceived(s) => {
let emojis = value.supports_emoji().then(|| {
let emojis = s.get_emoji();
let indices = s.get_emoji_index();
EmojiShortAuthString { emojis, indices }
});
let decimals = s.get_decimal();
Self::KeysExchanged { emojis, decimals }
}
InnerSas::Confirmed(_) => Self::Confirmed,
InnerSas::WaitingForDone(_) => Self::Confirmed,
InnerSas::Done(s) => Self::Done {
verified_devices: s.verified_devices().to_vec(),
verified_identities: s.verified_identities().to_vec(),
},
InnerSas::Cancelled(c) => Self::Cancelled(c.state.as_ref().clone().into()),
}
}
}
impl Sas {
/// Get our own user id.
pub fn user_id(&self) -> &UserId {
&self.account.user_id
}
/// Get our own device ID.
pub fn device_id(&self) -> &DeviceId {
&self.account.device_id
}
/// Get the user id of the other side.
pub fn other_user_id(&self) -> &UserId {
self.identities_being_verified.other_user_id()
}
/// Get the device ID of the other side.
pub fn other_device_id(&self) -> &DeviceId {
self.identities_being_verified.other_device_id()
}
/// Get the device of the other user.
pub fn other_device(&self) -> &DeviceData {
self.identities_being_verified.other_device()
}
/// Get the unique ID that identifies this SAS verification flow.
pub fn flow_id(&self) -> &FlowId {
&self.flow_id
}
/// Get the room id if the verification is happening inside a room.
pub fn room_id(&self) -> Option<&RoomId> {
as_variant!(self.flow_id(), FlowId::InRoom(r, _) => r)
}
/// Does this verification flow support displaying emoji for the short
/// authentication string.
pub fn supports_emoji(&self) -> bool {
self.inner.read().supports_emoji()
}
/// Did this verification flow start from a verification request.
pub fn started_from_request(&self) -> bool {
self.inner.read().started_from_request()
}
/// Is this a verification that is verifying one of our own devices.
pub fn is_self_verification(&self) -> bool {
self.identities_being_verified.is_self_verification()
}
/// Have we confirmed that the short auth string matches.
pub fn have_we_confirmed(&self) -> bool {
self.inner.read().have_we_confirmed()
}
/// Has the verification been accepted by both parties.
pub fn has_been_accepted(&self) -> bool {
self.inner.read().has_been_accepted()
}
/// Get info about the cancellation if the verification flow has been
/// cancelled.
pub fn cancel_info(&self) -> Option<CancelInfo> {
as_variant!(&*self.inner.read(), InnerSas::Cancelled(c) => {
c.state.as_ref().clone().into()
})
}
/// Did we initiate the verification flow.
pub fn we_started(&self) -> bool {
self.we_started
}
#[cfg(test)]
#[allow(dead_code)]
pub(crate) fn set_creation_time(&self, time: ruma::time::Instant) {
self.inner.update(|inner| {
inner.set_creation_time(time);
});
}
fn start_helper(
flow_id: FlowId,
identities: IdentitiesBeingVerified,
we_started: bool,
request_handle: Option<RequestHandle>,
short_auth_strings: Option<Vec<ShortAuthenticationString>>,
) -> (Sas, OutgoingContent) {
let (inner, content) = InnerSas::start(
identities.store.account.clone(),
identities.device_being_verified.clone(),
identities.own_identity.clone(),
identities.identity_being_verified.clone(),
flow_id.clone(),
request_handle.is_some(),
short_auth_strings,
);
let account = identities.store.account.clone();
(
Sas {
inner: SharedObservable::new(inner),
account,
identities_being_verified: identities,
flow_id: flow_id.into(),
we_started,
request_handle,
},
content,
)
}
/// Start a new SAS auth flow with the given device.
///
/// # Arguments
///
/// * `account` - Our own account.
///
/// * `other_device` - The other device which we are going to verify.
///
/// Returns the new `Sas` object and a `StartEventContent` that needs to be
/// sent out through the server to the other device.
pub(crate) fn start(
identities: IdentitiesBeingVerified,
transaction_id: OwnedTransactionId,
we_started: bool,
request_handle: Option<RequestHandle>,
short_auth_strings: Option<Vec<ShortAuthenticationString>>,
) -> (Sas, OutgoingContent) {
let flow_id = FlowId::ToDevice(transaction_id);
Self::start_helper(flow_id, identities, we_started, request_handle, short_auth_strings)
}
/// Start a new SAS auth flow with the given device inside the given room.
///
/// # Arguments
///
/// * `account` - Our own account.
///
/// * `other_device` - The other device which we are going to verify.
///
/// Returns the new `Sas` object and a `StartEventContent` that needs to be
/// sent out through the server to the other device.
#[allow(clippy::too_many_arguments)]
pub(crate) fn start_in_room(
flow_id: OwnedEventId,
room_id: OwnedRoomId,
identities: IdentitiesBeingVerified,
we_started: bool,
request_handle: RequestHandle,
) -> (Sas, OutgoingContent) {
let flow_id = FlowId::InRoom(room_id, flow_id);
Self::start_helper(flow_id, identities, we_started, Some(request_handle), None)
}
/// Create a new Sas object from a m.key.verification.start request.
///
/// # Arguments
///
/// * `account` - Our own account.
///
/// * `other_device` - The other device which we are going to verify.
///
/// * `event` - The m.key.verification.start event that was sent to us by
/// the other side.
pub(crate) fn from_start_event(
flow_id: FlowId,
content: &StartContent<'_>,
identities: IdentitiesBeingVerified,
request_handle: Option<RequestHandle>,
we_started: bool,
) -> Result<Sas, OutgoingContent> {
let inner = InnerSas::from_start_event(
identities.store.account.clone(),
identities.device_being_verified.clone(),
flow_id.clone(),
content,
identities.own_identity.clone(),
identities.identity_being_verified.clone(),
request_handle.is_some(),
)?;
let account = identities.store.account.clone();
Ok(Sas {
inner: SharedObservable::new(inner),
account,
identities_being_verified: identities,
flow_id: flow_id.into(),
we_started,
request_handle,
})
}
/// Accept the SAS verification.
///
/// This does nothing if the verification was already accepted, otherwise it
/// returns an `AcceptEventContent` that needs to be sent out.
pub fn accept(&self) -> Option<OutgoingVerificationRequest> {
let protocols = as_variant!(self.state(), SasState::Started { protocols } => protocols)?;
let settings = AcceptSettings { allowed_methods: protocols.short_authentication_string };
self.accept_with_settings(settings)
}
/// Accept the SAS verification customizing the accept method.
///
/// This does nothing if the verification was already accepted, otherwise it
/// returns an `AcceptEventContent` that needs to be sent out.
///
/// Specify a function modifying the attributes of the accept request.
pub fn accept_with_settings(
&self,
settings: AcceptSettings,
) -> Option<OutgoingVerificationRequest> {
let old_state = self.state_debug();
let request = {
let mut guard = self.inner.write();
let sas: InnerSas = (*guard).clone();
let methods = settings.allowed_methods;
if let Some((sas, content)) = sas.accept(methods) {
ObservableWriteGuard::set(&mut guard, sas);
Some(match content {
OwnedAcceptContent::ToDevice(c) => {
let content = AnyToDeviceEventContent::KeyVerificationAccept(c);
self.content_to_request(&content).into()
}
OwnedAcceptContent::Room(room_id, content) => RoomMessageRequest {
room_id,
txn_id: TransactionId::new(),
content: AnyMessageLikeEventContent::KeyVerificationAccept(content),
}
.into(),
})
} else {
None
}
};
let new_state = self.state_debug();
trace!(
flow_id = self.flow_id().as_str(),
?old_state,
?new_state,
"Accepted SAS verification"
);
request
}
/// Confirm the Sas verification.
///
/// This confirms that the short auth strings match on both sides.
///
/// Does nothing if we're not in a state where we can confirm the short auth
/// string, otherwise returns a `MacEventContent` that needs to be sent to
/// the server.
pub async fn confirm(
&self,
) -> Result<(Vec<OutgoingVerificationRequest>, Option<SignatureUploadRequest>), CryptoStoreError>
{
let (contents, done) = {
let mut guard = self.inner.write();
let sas: InnerSas = (*guard).clone();
let (sas, contents) = sas.confirm();
ObservableWriteGuard::set(&mut guard, sas);
(contents, guard.is_done())
};
let mac_requests = contents
.into_iter()
.map(|c| match c {
OutgoingContent::ToDevice(c) => self.content_to_request(&c).into(),
OutgoingContent::Room(r, c) => {
RoomMessageRequest { room_id: r, txn_id: TransactionId::new(), content: c }
.into()
}
})
.collect::<Vec<_>>();
if !mac_requests.is_empty() {
trace!(
user_id = ?self.other_user_id(),
device_id = ?self.other_device_id(),
"Confirming SAS verification"
)
}
if done {
match self.mark_as_done().await? {
VerificationResult::Cancel(c) => {
Ok((self.cancel_with_code(c).into_iter().collect(), None))
}
VerificationResult::Ok => Ok((mac_requests, None)),
VerificationResult::SignatureUpload(r) => Ok((mac_requests, Some(r))),
}
} else {
Ok((mac_requests, None))
}
}
pub(crate) async fn mark_as_done(&self) -> Result<VerificationResult, CryptoStoreError> {
self.identities_being_verified
.mark_as_done(self.verified_devices().as_deref(), self.verified_identities().as_deref())
.await
}
/// Cancel the verification.
///
/// This cancels the verification with the `CancelCode::User`.
///
/// Returns None if the `Sas` object is already in a canceled state,
/// otherwise it returns a request that needs to be sent out.
pub fn cancel(&self) -> Option<OutgoingVerificationRequest> {
self.cancel_with_code(CancelCode::User)
}
/// Cancel the verification.
///
/// This cancels the verification with given `CancelCode`.
///
/// **Note**: This method should generally not be used, the [`cancel()`]
/// method should be preferred. The SDK will automatically cancel with the
/// appropriate cancel code, user initiated cancellations should only cancel
/// with the `CancelCode::User`
///
/// Returns None if the `Sas` object is already in a canceled state,
/// otherwise it returns a request that needs to be sent out.
///
/// [`cancel()`]: #method.cancel
pub fn cancel_with_code(&self, code: CancelCode) -> Option<OutgoingVerificationRequest> {
let content = {
let mut guard = self.inner.write();
if let Some(request) = &self.request_handle {
request.cancel_with_code(&code);
}
let sas: InnerSas = (*guard).clone();
let (sas, content) = sas.cancel(true, code);
ObservableWriteGuard::set(&mut guard, sas);
content.map(|c| match c {
OutgoingContent::Room(room_id, content) => {
RoomMessageRequest { room_id, txn_id: TransactionId::new(), content }.into()
}
OutgoingContent::ToDevice(c) => self.content_to_request(&c).into(),
})
};
content
}
pub(crate) fn cancel_if_timed_out(&self) -> Option<OutgoingVerificationRequest> {
if self.is_cancelled() || self.is_done() {
None
} else if self.timed_out() {
self.cancel_with_code(CancelCode::Timeout)
} else {
None
}
}
/// Has the SAS verification flow timed out.
pub fn timed_out(&self) -> bool {
self.inner.read().timed_out()
}
/// Are we in a state where we can show the short auth string.
pub fn can_be_presented(&self) -> bool {
self.inner.read().can_be_presented()
}
/// Is the SAS flow done.
pub fn is_done(&self) -> bool {
self.inner.read().is_done()
}
/// Is the SAS flow canceled.
pub fn is_cancelled(&self) -> bool {
self.inner.read().is_cancelled()
}
/// Get the emoji version of the short auth string.
///
/// Returns None if we can't yet present the short auth string, otherwise
/// seven tuples containing the emoji and description.
pub fn emoji(&self) -> Option<[Emoji; 7]> {
self.inner.read().emoji()
}
/// Get the index of the emoji representing the short auth string
///
/// Returns None if we can't yet present the short auth string, otherwise
/// seven u8 numbers in the range from 0 to 63 inclusive which can be
/// converted to an emoji using the
/// [relevant spec entry](https://spec.matrix.org/unstable/client-server-api/#sas-method-emoji).
pub fn emoji_index(&self) -> Option<[u8; 7]> {
self.inner.read().emoji_index()
}
/// Get the decimal version of the short auth string.
///
/// Returns None if we can't yet present the short auth string, otherwise a
/// tuple containing three 4-digit integers that represent the short auth
/// string.
pub fn decimals(&self) -> Option<(u16, u16, u16)> {
self.inner.read().decimals()
}
/// Listen for changes in the SAS verification process.
///
/// The changes are presented as a stream of [`SasState`] values.
///
/// This method can be used to react to changes in the state of the
/// verification process, or rather the method can be used to handle
/// each step of the verification process.
///
/// # Flowchart
///
/// The flow of the verification process is pictured bellow. Please note
/// that the process can be cancelled at each step of the process.
/// Either side can cancel the process.
///
/// ```text
/// ┌───────┐
/// │Created│
/// └───┬───┘
/// │
/// ┌───⌄───┐
/// │Started│
/// └───┬───┘
/// │
/// ┌────⌄───┐
/// │Accepted│
/// └────┬───┘
/// │
/// ┌───────⌄──────┐
/// │Keys Exchanged│
/// └───────┬──────┘
/// │
/// ________⌄________
/// ╱ ╲ ┌─────────┐
/// ╱ Does the short ╲______│Cancelled│
/// ╲ auth string match ╱ no └─────────┘
/// ╲_________________╱
/// │yes
/// │
/// ┌────⌄────┐
/// │Confirmed│
/// └────┬────┘
/// │
/// ┌───⌄───┐
/// │ Done │
/// └───────┘
/// ```
///
/// # Examples
///
/// ```no_run
/// use futures_util::{Stream, StreamExt};
/// use matrix_sdk_crypto::{Sas, SasState};
///
/// # async {
/// # let sas: Sas = unimplemented!();
/// let mut stream = sas.changes();
///
/// while let Some(state) = stream.next().await {
/// match state {
/// SasState::KeysExchanged { emojis, decimals: _ } => {
/// let emojis =
/// emojis.expect("We only support emoji verification");
/// println!("Do these emojis match {emojis:#?}");
///
/// // Ask the user to confirm or cancel here.
/// }
/// SasState::Done { .. } => {
/// let device = sas.other_device();
///
/// println!(
/// "Successfully verified device {} {} {:?}",
/// device.user_id(),
/// device.device_id(),
/// device.local_trust_state()
/// );
///
/// break;
/// }
/// SasState::Cancelled(cancel_info) => {
/// println!(
/// "The verification has been cancelled, reason: {}",
/// cancel_info.reason()
/// );
/// break;
/// }
/// SasState::Created { .. }
/// | SasState::Started { .. }
/// | SasState::Accepted { .. }
/// | SasState::Confirmed => (),
/// }
/// }
/// # anyhow::Ok(()) };
/// ```
pub fn changes(&self) -> impl Stream<Item = SasState> {
self.inner.subscribe().map(|s| (&s).into())
}
/// Get the current state of the verification process.
pub fn state(&self) -> SasState {
(&*self.inner.read()).into()
}
fn state_debug(&self) -> State {
(&*self.inner.read()).into()
}
pub(crate) fn receive_any_event(
&self,
sender: &UserId,
content: &AnyVerificationContent<'_>,
) -> Option<(OutgoingContent, Option<RequestInfo>)> {
let old_state = self.state_debug();
let content = {
let mut guard = self.inner.write();
let sas: InnerSas = (*guard).clone();
let (sas, content) = sas.receive_any_event(sender, content);
ObservableWriteGuard::set(&mut guard, sas);
content
};
let new_state = self.state_debug();
trace!(
flow_id = self.flow_id().as_str(),
?old_state,
?new_state,
"SAS received an event and changed its state"
);
content
}
pub(crate) fn mark_request_as_sent(&self, request_id: &TransactionId) {
let old_state = self.state_debug();
{
let mut guard = self.inner.write();
let sas: InnerSas = (*guard).clone();
if let Some(sas) = sas.mark_request_as_sent(request_id) {
ObservableWriteGuard::set(&mut guard, sas);
} else {
error!(
flow_id = self.flow_id().as_str(),
?request_id,
"Tried to mark a request as sent, but the request ID didn't match"
);
}
};
let new_state = self.state_debug();
debug!(
flow_id = self.flow_id().as_str(),
?old_state,
?new_state,
?request_id,
"Marked a SAS verification HTTP request as sent"
);
}
pub(crate) fn verified_devices(&self) -> Option<Arc<[DeviceData]>> {
self.inner.read().verified_devices()
}
pub(crate) fn verified_identities(&self) -> Option<Arc<[UserIdentityData]>> {
self.inner.read().verified_identities()
}
pub(crate) fn content_to_request(&self, content: &AnyToDeviceEventContent) -> ToDeviceRequest {
ToDeviceRequest::with_id(
self.other_user_id(),
self.other_device_id().to_owned(),
content,
TransactionId::new(),
)
}
}
/// Customize the accept-reply for a verification process
#[derive(Debug)]
pub struct AcceptSettings {
allowed_methods: Vec<ShortAuthenticationString>,
}
impl Default for AcceptSettings {
/// All methods are allowed
fn default() -> Self {
Self {
allowed_methods: vec![
ShortAuthenticationString::Decimal,
ShortAuthenticationString::Emoji,
],
}
}
}
impl AcceptSettings {
/// Create settings restricting the allowed SAS methods
///
/// # Arguments
///
/// * `methods` - The methods this client allows at most
pub fn with_allowed_methods(methods: Vec<ShortAuthenticationString>) -> Self {
Self { allowed_methods: methods }
}
}
#[cfg(test)]
mod tests {
use std::sync::Arc;
use assert_matches::assert_matches;
use assert_matches2::assert_let;
use matrix_sdk_test::async_test;
use ruma::{
device_id,
events::key::verification::{accept::AcceptMethod, ShortAuthenticationString},
user_id, DeviceId, TransactionId, UserId,
};
use tokio::sync::Mutex;
use super::Sas;
use crate::{
olm::PrivateCrossSigningIdentity,
store::{CryptoStoreWrapper, MemoryStore},
verification::{
event_enums::{AcceptContent, KeyContent, MacContent, OutgoingContent, StartContent},
VerificationStore,
},
Account, DeviceData, SasState,
};
fn alice_id() -> &'static UserId {
user_id!("@alice:example.org")
}
fn alice_device_id() -> &'static DeviceId {
device_id!("JLAFKJWSCS")
}
fn bob_id() -> &'static UserId {
user_id!("@bob:example.org")
}
fn bob_device_id() -> &'static DeviceId {
device_id!("BOBDEVICE")
}
fn machine_pair_test_helper() -> (VerificationStore, DeviceData, VerificationStore, DeviceData)
{
let alice = Account::with_device_id(alice_id(), alice_device_id());
let alice_device = DeviceData::from_account(&alice);
let bob = Account::with_device_id(bob_id(), bob_device_id());
let bob_device = DeviceData::from_account(&bob);
let alice_store = VerificationStore {
account: alice.static_data.clone(),
inner: Arc::new(CryptoStoreWrapper::new(
alice.user_id(),
alice_device_id(),
MemoryStore::new(),
)),
private_identity: Mutex::new(PrivateCrossSigningIdentity::empty(alice_id())).into(),
};
let bob_store = MemoryStore::new();
bob_store.save_devices(vec![alice_device.clone()]);
let bob_store = VerificationStore {
account: bob.static_data.clone(),
inner: Arc::new(CryptoStoreWrapper::new(bob.user_id(), bob_device_id(), bob_store)),
private_identity: Mutex::new(PrivateCrossSigningIdentity::empty(bob_id())).into(),
};
(alice_store, alice_device, bob_store, bob_device)
}
#[async_test]
async fn test_sas_wrapper_full() {
let (alice_store, alice_device, bob_store, bob_device) = machine_pair_test_helper();
let identities = alice_store.get_identities(bob_device).await.unwrap();
let (alice, content) = Sas::start(identities, TransactionId::new(), true, None, None);
assert_matches!(alice.state(), SasState::Created { .. });
let flow_id = alice.flow_id().to_owned();
let content = StartContent::try_from(&content).unwrap();
let identities = bob_store.get_identities(alice_device).await.unwrap();
let bob = Sas::from_start_event(flow_id, &content, identities, None, false).unwrap();
assert_matches!(bob.state(), SasState::Started { .. });
let request = bob.accept().unwrap();
let content = OutgoingContent::try_from(request).unwrap();
let content = AcceptContent::try_from(&content).unwrap();
let (content, request_info) =
alice.receive_any_event(bob.user_id(), &content.into()).unwrap();
assert_matches!(alice.state(), SasState::Accepted { .. });
assert_matches!(bob.state(), SasState::Accepted { .. });
assert!(!alice.can_be_presented());
assert!(!bob.can_be_presented());
alice.mark_request_as_sent(&request_info.unwrap().request_id);
let content = KeyContent::try_from(&content).unwrap();
let (content, request_info) =
bob.receive_any_event(alice.user_id(), &content.into()).unwrap();
assert!(!bob.can_be_presented());
assert_matches!(bob.state(), SasState::Accepted { .. });
bob.mark_request_as_sent(&request_info.unwrap().request_id);
assert!(bob.can_be_presented());
assert_matches!(bob.state(), SasState::KeysExchanged { .. });
let content = KeyContent::try_from(&content).unwrap();
alice.receive_any_event(bob.user_id(), &content.into());
assert_matches!(alice.state(), SasState::KeysExchanged { .. });
assert!(alice.can_be_presented());
assert_eq!(alice.emoji().unwrap(), bob.emoji().unwrap());
assert_eq!(alice.decimals().unwrap(), bob.decimals().unwrap());
let mut requests = alice.confirm().await.unwrap().0;
assert_matches!(alice.state(), SasState::Confirmed);
assert!(requests.len() == 1);
let request = requests.pop().unwrap();
let content = OutgoingContent::try_from(request).unwrap();
let content = MacContent::try_from(&content).unwrap();
bob.receive_any_event(alice.user_id(), &content.into());
assert_matches!(bob.state(), SasState::KeysExchanged { .. });
let mut requests = bob.confirm().await.unwrap().0;
assert_matches!(bob.state(), SasState::Done { .. });
assert!(requests.len() == 1);
let request = requests.pop().unwrap();
let content = OutgoingContent::try_from(request).unwrap();
let content = MacContent::try_from(&content).unwrap();
alice.receive_any_event(bob.user_id(), &content.into());
assert!(alice.verified_devices().unwrap().contains(alice.other_device()));
assert!(bob.verified_devices().unwrap().contains(bob.other_device()));
assert_matches!(alice.state(), SasState::Done { .. });
assert_matches!(bob.state(), SasState::Done { .. });
}
#[async_test]
async fn test_sas_with_restricted_methods() {
let (alice_store, alice_device, bob_store, bob_device) = machine_pair_test_helper();
let identities = alice_store.get_identities(bob_device).await.unwrap();
let short_auth_strings = vec![ShortAuthenticationString::Decimal];
let (alice, content) =
Sas::start(identities, TransactionId::new(), true, None, Some(short_auth_strings));
let flow_id = alice.flow_id().to_owned();
let content = StartContent::try_from(&content).unwrap();
let identities = bob_store.get_identities(alice_device).await.unwrap();
let bob = Sas::from_start_event(flow_id, &content, identities, None, false).unwrap();
let request = bob.accept().unwrap();
let content = OutgoingContent::try_from(request).unwrap();
let content = AcceptContent::try_from(&content).unwrap();
assert_let!(AcceptMethod::SasV1(content) = content.method());
assert!(content.short_authentication_string.contains(&ShortAuthenticationString::Decimal));
assert!(!content.short_authentication_string.contains(&ShortAuthenticationString::Emoji));
}
}