crypto: Move the logic for marking identities as verified out of the Sas struct

This commit is contained in:
Damir Jelić 2021-05-31 16:31:35 +02:00
parent 8a5a0e511e
commit 327445c6a0
6 changed files with 335 additions and 263 deletions

View file

@ -138,7 +138,7 @@ impl Sas {
}
/// Get the other users device that we're veryfying.
pub fn other_device(&self) -> ReadOnlyDevice {
pub fn other_device(&self) -> &ReadOnlyDevice {
self.inner.other_device()
}
}

View file

@ -28,7 +28,8 @@ use tracing::{info, trace, warn};
use super::{
requests::VerificationRequest,
sas::{content_to_request, OutgoingContent, Sas, VerificationResult},
sas::{content_to_request, OutgoingContent, Sas},
VerificationResult,
};
use crate::{
olm::PrivateCrossSigningIdentity,
@ -341,8 +342,10 @@ impl VerificationMachine {
);
}
}
VerificationResult::Cancel(r) => {
self.verifications.add_request(r.into());
VerificationResult::Cancel(c) => {
if let Some(r) = s.cancel_with_code(c) {
self.verifications.add_request(r.into());
}
}
VerificationResult::SignatureUpload(r) => {
self.verifications.add_request(r.into());
@ -453,8 +456,10 @@ impl VerificationMachine {
if s.is_done() {
match s.mark_as_done().await? {
VerificationResult::Ok => (),
VerificationResult::Cancel(r) => {
self.verifications.add_request(r.into());
VerificationResult::Cancel(c) => {
if let Some(r) = s.cancel_with_code(c) {
self.verifications.add_request(r.into());
}
}
VerificationResult::SignatureUpload(r) => {
self.verifications.add_request(r.into());

View file

@ -16,16 +16,28 @@ mod machine;
mod requests;
mod sas;
pub use machine::{VerificationCache, VerificationMachine};
use std::sync::Arc;
use matrix_sdk_common::{
api::r0::keys::upload_signatures::Request as SignatureUploadRequest,
events::key::verification::{
cancel::{CancelCode, CancelEventContent, CancelToDeviceEventContent},
Relation,
},
identifiers::{EventId, RoomId},
identifiers::{DeviceId, EventId, RoomId, UserId},
};
pub use machine::{VerificationCache, VerificationMachine};
pub use requests::VerificationRequest;
pub use sas::{AcceptSettings, Sas, VerificationResult};
pub use sas::{AcceptSettings, Sas};
use tracing::{error, info, trace, warn};
use crate::{
error::SignatureError,
olm::PrivateCrossSigningIdentity,
store::{Changes, CryptoStore, DeviceChanges},
CryptoStoreError, LocalTrust, ReadOnlyDevice, UserIdentities,
};
use self::sas::CancelContent;
@ -116,6 +128,253 @@ impl From<(RoomId, EventId)> for FlowId {
}
}
/// A result of a verification flow.
#[derive(Clone, Debug)]
pub enum VerificationResult {
/// The verification succeeded, nothing needs to be done.
Ok,
/// The verification was canceled.
Cancel(CancelCode),
/// The verification is done and has signatures that need to be uploaded.
SignatureUpload(SignatureUploadRequest),
}
#[derive(Clone, Debug)]
pub struct IdentitiesBeingVerified {
private_identity: PrivateCrossSigningIdentity,
store: Arc<Box<dyn CryptoStore>>,
device_being_verified: ReadOnlyDevice,
identity_being_verified: Option<UserIdentities>,
}
#[allow(dead_code)]
impl IdentitiesBeingVerified {
fn user_id(&self) -> &UserId {
self.private_identity.user_id()
}
fn other_user_id(&self) -> &UserId {
self.device_being_verified.user_id()
}
fn other_device_id(&self) -> &DeviceId {
self.device_being_verified.device_id()
}
fn other_device(&self) -> &ReadOnlyDevice {
&self.device_being_verified
}
pub async fn mark_as_done(
&self,
verified_devices: Option<&[ReadOnlyDevice]>,
verified_identities: Option<&[UserIdentities]>,
) -> Result<VerificationResult, CryptoStoreError> {
if let Some(device) = self.mark_device_as_verified(verified_devices).await? {
let identity = self.mark_identity_as_verified(verified_identities).await?;
// We only sign devices of our own user here.
let signature_request = if device.user_id() == self.user_id() {
match self.private_identity.sign_device(&device).await {
Ok(r) => Some(r),
Err(SignatureError::MissingSigningKey) => {
warn!(
"Can't sign the device keys for {} {}, \
no private user signing key found",
device.user_id(),
device.device_id(),
);
None
}
Err(e) => {
error!(
"Error signing device keys for {} {} {:?}",
device.user_id(),
device.device_id(),
e
);
None
}
}
} else {
None
};
let mut changes = Changes {
devices: DeviceChanges { changed: vec![device], ..Default::default() },
..Default::default()
};
let identity_signature_request = if let Some(i) = identity {
// We only sign other users here.
let request = if let Some(i) = i.other() {
// Signing can fail if the user signing key is missing.
match self.private_identity.sign_user(&i).await {
Ok(r) => Some(r),
Err(SignatureError::MissingSigningKey) => {
warn!(
"Can't sign the public cross signing keys for {}, \
no private user signing key found",
i.user_id()
);
None
}
Err(e) => {
error!(
"Error signing the public cross signing keys for {} {:?}",
i.user_id(),
e
);
None
}
}
} else {
None
};
changes.identities.changed.push(i);
request
} else {
None
};
// If there are two signature upload requests, merge them. Otherwise
// use the one we have or None.
//
// Realistically at most one request will be used but let's make
// this future proof.
let merged_request = if let Some(mut r) = signature_request {
if let Some(user_request) = identity_signature_request {
r.signed_keys.extend(user_request.signed_keys);
Some(r)
} else {
Some(r)
}
} else {
identity_signature_request
};
// TODO store the signature upload request as well.
self.store.save_changes(changes).await?;
Ok(merged_request
.map(VerificationResult::SignatureUpload)
.unwrap_or(VerificationResult::Ok))
} else {
Ok(VerificationResult::Cancel(CancelCode::UserMismatch))
}
}
async fn mark_identity_as_verified(
&self,
verified_identities: Option<&[UserIdentities]>,
) -> Result<Option<UserIdentities>, CryptoStoreError> {
// If there wasn't an identity available during the verification flow
// return early as there's nothing to do.
if self.identity_being_verified.is_none() {
return Ok(None);
}
// TODO signal an error, e.g. when the identity got deleted so we don't
// verify/save the device either.
let identity = self.store.get_user_identity(self.other_user_id()).await?;
if let Some(identity) = identity {
if self
.identity_being_verified
.as_ref()
.map_or(false, |i| i.master_key() == identity.master_key())
{
if verified_identities.map_or(false, |i| i.contains(&identity)) {
trace!("Marking user identity of {} as verified.", identity.user_id(),);
if let UserIdentities::Own(i) = &identity {
i.mark_as_verified();
}
Ok(Some(identity))
} else {
info!(
"The interactive verification process didn't verify \
the user identity of {} {:?}",
identity.user_id(),
verified_identities,
);
Ok(None)
}
} else {
warn!(
"The master keys of {} have changed while an interactive \
verification was going on, not marking the identity as verified.",
identity.user_id(),
);
Ok(None)
}
} else {
info!(
"The identity for {} was deleted while an interactive \
verification was going on.",
self.other_user_id(),
);
Ok(None)
}
}
async fn mark_device_as_verified(
&self,
verified_devices: Option<&[ReadOnlyDevice]>,
) -> Result<Option<ReadOnlyDevice>, CryptoStoreError> {
let device = self.store.get_device(self.other_user_id(), self.other_device_id()).await?;
if let Some(device) = device {
if device.keys() == self.device_being_verified.keys() {
if verified_devices.map_or(false, |v| v.contains(&device)) {
trace!(
user_id = device.user_id().as_str(),
device_id = device.device_id().as_str(),
"Marking device as verified.",
);
device.set_trust_state(LocalTrust::Verified);
Ok(Some(device))
} else {
info!(
user_id = device.user_id().as_str(),
device_id = device.device_id().as_str(),
"The interactive verification process didn't verify \
the device",
);
Ok(None)
}
} else {
warn!(
user_id = device.user_id().as_str(),
device_id = device.device_id().as_str(),
"The device keys have changed while an interactive \
verification was going on, not marking the device as verified.",
);
Ok(None)
}
} else {
let device = &self.device_being_verified;
info!(
user_id = device.user_id().as_str(),
device_id = device.device_id().as_str(),
"The device was deleted while an interactive verification was \
going on.",
);
Ok(None)
}
}
}
#[cfg(test)]
pub(crate) mod test {
use matrix_sdk_common::{

View file

@ -23,6 +23,7 @@ use matrix_sdk_common::{
api::r0::to_device::DeviceIdOrAllDevices,
events::{
key::verification::{
done::{DoneEventContent, DoneToDeviceEventContent},
ready::{ReadyEventContent, ReadyToDeviceEventContent},
request::RequestToDeviceEventContent,
start::{StartEventContent, StartMethod, StartToDeviceEventContent},
@ -35,7 +36,7 @@ use matrix_sdk_common::{
uuid::Uuid,
MilliSecondsSinceUnixEpoch,
};
use tracing::{info, warn};
use tracing::{info, trace, warn};
use super::{
sas::{content_to_request, OutgoingContent, StartContent as OwnedStartContent},
@ -202,6 +203,32 @@ impl<'a> TryFrom<&'a OutgoingContent> for StartContent<'a> {
}
}
pub enum DoneContent<'a> {
ToDevice(&'a DoneToDeviceEventContent),
Room(&'a DoneEventContent),
}
impl<'a> From<&'a DoneEventContent> for DoneContent<'a> {
fn from(c: &'a DoneEventContent) -> Self {
Self::Room(c)
}
}
impl<'a> From<&'a DoneToDeviceEventContent> for DoneContent<'a> {
fn from(c: &'a DoneToDeviceEventContent) -> Self {
Self::ToDevice(c)
}
}
impl<'a> DoneContent<'a> {
pub fn flow_id(&self) -> &str {
match self {
Self::ToDevice(c) => &c.transaction_id,
Self::Room(c) => &c.relation.event_id.as_str(),
}
}
}
#[derive(Clone, Debug)]
/// TODO
pub struct VerificationRequest {

View file

@ -109,6 +109,7 @@ impl From<(RoomId, AcceptEventContent)> for AcceptContent {
}
}
#[derive(Clone, Debug)]
pub enum KeyContent {
ToDevice(KeyToDeviceEventContent),
Room(RoomId, KeyEventContent),
@ -142,6 +143,7 @@ impl From<(RoomId, KeyEventContent)> for KeyContent {
}
}
#[derive(Clone, Debug)]
pub enum MacContent {
ToDevice(MacToDeviceEventContent),
Room(RoomId, MacEventContent),
@ -182,6 +184,7 @@ impl From<(RoomId, MacEventContent)> for MacContent {
}
}
#[derive(Clone, Debug)]
pub enum CancelContent {
ToDevice(CancelToDeviceEventContent),
Room(RoomId, CancelEventContent),
@ -199,6 +202,7 @@ impl From<CancelToDeviceEventContent> for CancelContent {
}
}
#[derive(Clone, Debug)]
pub enum DoneContent {
Room(RoomId, DoneEventContent),
}

View file

@ -38,39 +38,22 @@ use matrix_sdk_common::{
identifiers::{DeviceId, EventId, RoomId, UserId},
uuid::Uuid,
};
use tracing::{error, info, trace, warn};
use super::FlowId;
use super::{FlowId, IdentitiesBeingVerified, VerificationResult};
use crate::{
error::SignatureError,
identities::{LocalTrust, ReadOnlyDevice, UserIdentities},
identities::{ReadOnlyDevice, UserIdentities},
olm::PrivateCrossSigningIdentity,
requests::{OutgoingVerificationRequest, RoomMessageRequest},
store::{Changes, CryptoStore, CryptoStoreError, DeviceChanges},
store::{CryptoStore, CryptoStoreError},
ReadOnlyAccount, ToDeviceRequest,
};
#[derive(Debug)]
/// A result of a verification flow.
#[allow(clippy::large_enum_variant)]
pub enum VerificationResult {
/// The verification succeeded, nothing needs to be done.
Ok,
/// The verification was canceled.
Cancel(OutgoingVerificationRequest),
/// The verification is done and has signatures that need to be uploaded.
SignatureUpload(SignatureUploadRequest),
}
#[derive(Clone, Debug)]
/// Short authentication string object.
pub struct Sas {
inner: Arc<Mutex<InnerSas>>,
store: Arc<Box<dyn CryptoStore>>,
account: ReadOnlyAccount,
private_identity: PrivateCrossSigningIdentity,
other_device: ReadOnlyDevice,
other_identity: Option<UserIdentities>,
identities_being_verified: IdentitiesBeingVerified,
flow_id: Arc<FlowId>,
}
@ -87,17 +70,17 @@ impl Sas {
/// Get the user id of the other side.
pub fn other_user_id(&self) -> &UserId {
self.other_device.user_id()
self.identities_being_verified.other_user_id()
}
/// Get the device id of the other side.
pub fn other_device_id(&self) -> &DeviceId {
self.other_device.device_id()
self.identities_being_verified.other_device_id()
}
/// Get the device of the other user.
pub fn other_device(&self) -> ReadOnlyDevice {
self.other_device.clone()
pub fn other_device(&self) -> &ReadOnlyDevice {
self.identities_being_verified.other_device()
}
/// Get the unique ID that identifies this SAS verification flow.
@ -127,14 +110,18 @@ impl Sas {
) -> Sas {
let flow_id = inner_sas.verification_flow_id();
let identities = IdentitiesBeingVerified {
private_identity: private_identity.clone(),
store: store.clone(),
device_being_verified: other_device.clone(),
identity_being_verified: other_identity.clone(),
};
Sas {
inner: Arc::new(Mutex::new(inner_sas)),
account,
private_identity,
store,
other_device,
identities_being_verified: identities,
flow_id,
other_identity,
}
}
@ -241,17 +228,14 @@ impl Sas {
other_identity.clone(),
)?;
let flow_id = inner.verification_flow_id();
Ok(Sas {
inner: Arc::new(Mutex::new(inner)),
Ok(Self::start_helper(
inner,
account,
private_identity,
other_device,
other_identity,
store,
flow_id,
})
other_identity,
))
}
/// Accept the SAS verification.
@ -322,7 +306,7 @@ impl Sas {
if done {
match self.mark_as_done().await? {
VerificationResult::Cancel(r) => Ok((Some(r), None)),
VerificationResult::Cancel(c) => Ok((self.cancel_with_code(c), None)),
VerificationResult::Ok => Ok((mac_request, None)),
VerificationResult::SignatureUpload(r) => Ok((mac_request, Some(r))),
}
@ -332,205 +316,9 @@ impl Sas {
}
pub(crate) async fn mark_as_done(&self) -> Result<VerificationResult, CryptoStoreError> {
if let Some(device) = self.mark_device_as_verified().await? {
let identity = self.mark_identity_as_verified().await?;
// We only sign devices of our own user here.
let signature_request = if device.user_id() == self.user_id() {
match self.private_identity.sign_device(&device).await {
Ok(r) => Some(r),
Err(SignatureError::MissingSigningKey) => {
warn!(
"Can't sign the device keys for {} {}, \
no private user signing key found",
device.user_id(),
device.device_id(),
);
None
}
Err(e) => {
error!(
"Error signing device keys for {} {} {:?}",
device.user_id(),
device.device_id(),
e
);
None
}
}
} else {
None
};
let mut changes = Changes {
devices: DeviceChanges { changed: vec![device], ..Default::default() },
..Default::default()
};
let identity_signature_request = if let Some(i) = identity {
// We only sign other users here.
let request = if let Some(i) = i.other() {
// Signing can fail if the user signing key is missing.
match self.private_identity.sign_user(&i).await {
Ok(r) => Some(r),
Err(SignatureError::MissingSigningKey) => {
warn!(
"Can't sign the public cross signing keys for {}, \
no private user signing key found",
i.user_id()
);
None
}
Err(e) => {
error!(
"Error signing the public cross signing keys for {} {:?}",
i.user_id(),
e
);
None
}
}
} else {
None
};
changes.identities.changed.push(i);
request
} else {
None
};
// If there are two signature upload requests, merge them. Otherwise
// use the one we have or None.
//
// Realistically at most one reuqest will be used but let's make
// this future proof.
let merged_request = if let Some(mut r) = signature_request {
if let Some(user_request) = identity_signature_request {
r.signed_keys.extend(user_request.signed_keys);
Some(r)
} else {
Some(r)
}
} else {
identity_signature_request
};
// TODO store the request as well.
self.store.save_changes(changes).await?;
Ok(merged_request
.map(VerificationResult::SignatureUpload)
.unwrap_or(VerificationResult::Ok))
} else {
Ok(self.cancel().map(VerificationResult::Cancel).unwrap_or(VerificationResult::Ok))
}
}
pub(crate) async fn mark_identity_as_verified(
&self,
) -> Result<Option<UserIdentities>, CryptoStoreError> {
// If there wasn't an identity available during the verification flow
// return early as there's nothing to do.
if self.other_identity.is_none() {
return Ok(None);
}
// TODO signal an error, e.g. when the identity got deleted so we don't
// verify/save the device either.
let identity = self.store.get_user_identity(self.other_user_id()).await?;
if let Some(identity) = identity {
if self
.other_identity
.as_ref()
.map_or(false, |i| i.master_key() == identity.master_key())
{
if self.verified_identities().map_or(false, |i| i.contains(&identity)) {
trace!("Marking user identity of {} as verified.", identity.user_id(),);
if let UserIdentities::Own(i) = &identity {
i.mark_as_verified();
}
Ok(Some(identity))
} else {
info!(
"The interactive verification process didn't contain a \
MAC for the user identity of {} {:?}",
identity.user_id(),
self.verified_identities(),
);
Ok(None)
}
} else {
warn!(
"The master keys of {} have changed while an interactive \
verification was going on, not marking the identity as verified.",
identity.user_id(),
);
Ok(None)
}
} else {
info!(
"The identity for {} was deleted while an interactive \
verification was going on.",
self.other_user_id(),
);
Ok(None)
}
}
pub(crate) async fn mark_device_as_verified(
&self,
) -> Result<Option<ReadOnlyDevice>, CryptoStoreError> {
let device = self.store.get_device(self.other_user_id(), self.other_device_id()).await?;
if let Some(device) = device {
if device.keys() == self.other_device.keys() {
if self.verified_devices().map_or(false, |v| v.contains(&device)) {
trace!(
"Marking device {} {} as verified.",
device.user_id(),
device.device_id()
);
device.set_trust_state(LocalTrust::Verified);
Ok(Some(device))
} else {
info!(
"The interactive verification process didn't contain a \
MAC for the device {} {}",
device.user_id(),
device.device_id()
);
Ok(None)
}
} else {
warn!(
"The device keys of {} {} have changed while an interactive \
verification was going on, not marking the device as verified.",
device.user_id(),
device.device_id()
);
Ok(None)
}
} else {
let device = self.other_device();
info!(
"The device {} {} was deleted while an interactive \
verification was going on.",
device.user_id(),
device.device_id()
);
Ok(None)
}
self.identities_being_verified
.mark_as_done(self.verified_devices().as_deref(), self.verified_identities().as_deref())
.await
}
/// Cancel the verification.
@ -540,11 +328,14 @@ impl Sas {
/// 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)
}
pub(crate) fn cancel_with_code(&self, code: CancelCode) -> Option<OutgoingVerificationRequest> {
let mut guard = self.inner.lock().unwrap();
let sas: InnerSas = (*guard).clone();
let (sas, content) = sas.cancel(CancelCode::User);
let (sas, content) = sas.cancel(code);
*guard = sas;
content.map(|c| match c {
CancelContent::Room(room_id, content) => RoomMessageRequest {
room_id,
@ -562,21 +353,7 @@ impl Sas {
if self.is_cancelled() || self.is_done() {
None
} else if self.timed_out() {
let mut guard = self.inner.lock().unwrap();
let sas: InnerSas = (*guard).clone();
let (sas, content) = sas.cancel(CancelCode::Timeout);
*guard = sas;
content.map(|c| match c {
CancelContent::Room(room_id, content) => RoomMessageRequest {
room_id,
txn_id: Uuid::new_v4(),
content: AnyMessageEventContent::KeyVerificationCancel(content),
}
.into(),
CancelContent::ToDevice(c) => self
.content_to_request(AnyToDeviceEventContent::KeyVerificationCancel(c))
.into(),
})
self.cancel_with_code(CancelCode::Timeout)
} else {
None
}