205 lines
7.6 KiB
Go
205 lines
7.6 KiB
Go
// Copyright (c) 2020 Tulir Asokan
|
|
//
|
|
// This Source Code Form is subject to the terms of the Mozilla Public
|
|
// License, v. 2.0. If a copy of the MPL was not distributed with this
|
|
// file, You can obtain one at http://mozilla.org/MPL/2.0/.
|
|
|
|
package crypto
|
|
|
|
import (
|
|
"errors"
|
|
"fmt"
|
|
|
|
"maunium.net/go/mautrix"
|
|
"maunium.net/go/mautrix/crypto/olm"
|
|
"maunium.net/go/mautrix/id"
|
|
)
|
|
|
|
var (
|
|
MismatchingDeviceID = errors.New("mismatching device ID in parameter and keys object")
|
|
MismatchingUserID = errors.New("mismatching user ID in parameter and keys object")
|
|
MismatchingSigningKey = errors.New("received update for device with different signing key")
|
|
NoSigningKeyFound = errors.New("didn't find ed25519 signing key")
|
|
NoIdentityKeyFound = errors.New("didn't find curve25519 identity key")
|
|
InvalidKeySignature = errors.New("invalid signature on device keys")
|
|
)
|
|
|
|
func (mach *OlmMachine) LoadDevices(user id.UserID) map[id.DeviceID]*id.Device {
|
|
return mach.fetchKeys([]id.UserID{user}, "", true)[user]
|
|
}
|
|
|
|
func (mach *OlmMachine) storeDeviceSelfSignatures(userID id.UserID, deviceID id.DeviceID, resp *mautrix.RespQueryKeys) {
|
|
deviceKeys := resp.DeviceKeys[userID][deviceID]
|
|
for signerUserID, signerKeys := range deviceKeys.Signatures {
|
|
for signerKey, signature := range signerKeys {
|
|
// verify and save self-signing key signature for each device
|
|
if selfSignKeys, ok := resp.SelfSigningKeys[signerUserID]; ok {
|
|
for _, pubKey := range selfSignKeys.Keys {
|
|
if selfSigs, ok := deviceKeys.Signatures[signerUserID]; !ok {
|
|
continue
|
|
} else if _, ok := selfSigs[id.NewKeyID(id.KeyAlgorithmEd25519, pubKey.String())]; !ok {
|
|
continue
|
|
}
|
|
if verified, err := olm.VerifySignatureJSON(deviceKeys, signerUserID, pubKey.String(), pubKey); verified {
|
|
if signKey, ok := deviceKeys.Keys[id.DeviceKeyID(signerKey)]; ok {
|
|
signature := deviceKeys.Signatures[signerUserID][id.NewKeyID(id.KeyAlgorithmEd25519, pubKey.String())]
|
|
mach.Log.Trace("Verified self-signing signature for device %s/%s: %s", signerUserID, deviceID, signature)
|
|
err = mach.CryptoStore.PutSignature(userID, id.Ed25519(signKey), signerUserID, pubKey, signature)
|
|
if err != nil {
|
|
mach.Log.Warn("Failed to store self-signing signature for device %s/%s: %v", signerUserID, deviceID, err)
|
|
}
|
|
}
|
|
} else {
|
|
if err == nil {
|
|
err = errors.New("invalid signature")
|
|
}
|
|
mach.Log.Warn("Could not verify device self-signing signature for %s/%s: %v", signerUserID, deviceID, err)
|
|
}
|
|
}
|
|
}
|
|
// save signature of device made by its own device signing key
|
|
if signKey, ok := deviceKeys.Keys[id.DeviceKeyID(signerKey)]; ok {
|
|
err := mach.CryptoStore.PutSignature(userID, id.Ed25519(signKey), signerUserID, id.Ed25519(signKey), signature)
|
|
if err != nil {
|
|
mach.Log.Warn("Failed to store self-signing signature for %s/%s: %v", signerUserID, signKey, err)
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
func (mach *OlmMachine) fetchKeys(users []id.UserID, sinceToken string, includeUntracked bool) (data map[id.UserID]map[id.DeviceID]*id.Device) {
|
|
// TODO this function should probably return errors
|
|
req := &mautrix.ReqQueryKeys{
|
|
DeviceKeys: mautrix.DeviceKeysRequest{},
|
|
Timeout: 10 * 1000,
|
|
Token: sinceToken,
|
|
}
|
|
if !includeUntracked {
|
|
var err error
|
|
users, err = mach.CryptoStore.FilterTrackedUsers(users)
|
|
if err != nil {
|
|
mach.Log.Warn("Failed to filter tracked user list: %v", err)
|
|
}
|
|
}
|
|
if len(users) == 0 {
|
|
return
|
|
}
|
|
for _, userID := range users {
|
|
req.DeviceKeys[userID] = mautrix.DeviceIDList{}
|
|
}
|
|
mach.Log.Trace("Querying keys for %v", users)
|
|
resp, err := mach.Client.QueryKeys(req)
|
|
if err != nil {
|
|
mach.Log.Warn("Failed to query keys: %v", err)
|
|
return
|
|
}
|
|
for server, err := range resp.Failures {
|
|
mach.Log.Warn("Query keys failure for %s: %v", server, err)
|
|
}
|
|
mach.Log.Trace("Query key result received with %d users", len(resp.DeviceKeys))
|
|
data = make(map[id.UserID]map[id.DeviceID]*id.Device)
|
|
for userID, devices := range resp.DeviceKeys {
|
|
delete(req.DeviceKeys, userID)
|
|
|
|
newDevices := make(map[id.DeviceID]*id.Device)
|
|
existingDevices, err := mach.CryptoStore.GetDevices(userID)
|
|
if err != nil {
|
|
mach.Log.Warn("Failed to get existing devices for %s: %v", userID, err)
|
|
existingDevices = make(map[id.DeviceID]*id.Device)
|
|
}
|
|
mach.Log.Trace("Updating devices for %s, got %d devices, have %d in store", userID, len(devices), len(existingDevices))
|
|
changed := false
|
|
for deviceID, deviceKeys := range devices {
|
|
existing, ok := existingDevices[deviceID]
|
|
if !ok {
|
|
// New device
|
|
changed = true
|
|
}
|
|
mach.Log.Trace("Validating device %s of %s", deviceID, userID)
|
|
newDevice, err := mach.validateDevice(userID, deviceID, deviceKeys, existing)
|
|
if err != nil {
|
|
mach.Log.Error("Failed to validate device %s of %s: %v", deviceID, userID, err)
|
|
} else if newDevice != nil {
|
|
newDevices[deviceID] = newDevice
|
|
mach.storeDeviceSelfSignatures(userID, deviceID, resp)
|
|
}
|
|
}
|
|
mach.Log.Trace("Storing new device list for %s containing %d devices", userID, len(newDevices))
|
|
err = mach.CryptoStore.PutDevices(userID, newDevices)
|
|
if err != nil {
|
|
mach.Log.Warn("Failed to update device list for %s: %v", userID, err)
|
|
}
|
|
data[userID] = newDevices
|
|
|
|
changed = changed || len(newDevices) != len(existingDevices)
|
|
if changed {
|
|
mach.OnDevicesChanged(userID)
|
|
}
|
|
}
|
|
for userID := range req.DeviceKeys {
|
|
mach.Log.Warn("Didn't get any keys for user %s", userID)
|
|
}
|
|
|
|
mach.storeCrossSigningKeys(resp.MasterKeys, resp.DeviceKeys)
|
|
mach.storeCrossSigningKeys(resp.SelfSigningKeys, resp.DeviceKeys)
|
|
mach.storeCrossSigningKeys(resp.UserSigningKeys, resp.DeviceKeys)
|
|
|
|
return data
|
|
}
|
|
|
|
// OnDevicesChanged finds all shared rooms with the given user and invalidates outbound sessions in those rooms.
|
|
//
|
|
// This is called automatically whenever a device list change is noticed in ProcessSyncResponse and usually does
|
|
// not need to be called manually.
|
|
func (mach *OlmMachine) OnDevicesChanged(userID id.UserID) {
|
|
for _, roomID := range mach.StateStore.FindSharedRooms(userID) {
|
|
mach.Log.Debug("Devices of %s changed, invalidating group session for %s", userID, roomID)
|
|
err := mach.CryptoStore.RemoveOutboundGroupSession(roomID)
|
|
if err != nil {
|
|
mach.Log.Warn("Failed to invalidate outbound group session of %s on device change for %s: %v", roomID, userID, err)
|
|
}
|
|
}
|
|
}
|
|
|
|
func (mach *OlmMachine) validateDevice(userID id.UserID, deviceID id.DeviceID, deviceKeys mautrix.DeviceKeys, existing *id.Device) (*id.Device, error) {
|
|
if deviceID != deviceKeys.DeviceID {
|
|
return nil, fmt.Errorf("%w (expected %s, got %s)", MismatchingDeviceID, deviceID, deviceKeys.DeviceID)
|
|
} else if userID != deviceKeys.UserID {
|
|
return nil, fmt.Errorf("%w (expected %s, got %s)", MismatchingUserID, userID, deviceKeys.UserID)
|
|
}
|
|
|
|
signingKey := deviceKeys.Keys.GetEd25519(deviceID)
|
|
identityKey := deviceKeys.Keys.GetCurve25519(deviceID)
|
|
if signingKey == "" {
|
|
return nil, NoSigningKeyFound
|
|
} else if identityKey == "" {
|
|
return nil, NoIdentityKeyFound
|
|
}
|
|
|
|
if existing != nil && existing.SigningKey != signingKey {
|
|
return existing, fmt.Errorf("%w (expected %s, got %s)", MismatchingSigningKey, existing.SigningKey, signingKey)
|
|
}
|
|
|
|
ok, err := olm.VerifySignatureJSON(deviceKeys, userID, deviceID.String(), signingKey)
|
|
if err != nil {
|
|
return existing, fmt.Errorf("failed to verify signature: %w", err)
|
|
} else if !ok {
|
|
return existing, InvalidKeySignature
|
|
}
|
|
|
|
name, ok := deviceKeys.Unsigned["device_display_name"].(string)
|
|
if !ok {
|
|
name = string(deviceID)
|
|
}
|
|
|
|
return &id.Device{
|
|
UserID: userID,
|
|
DeviceID: deviceID,
|
|
IdentityKey: identityKey,
|
|
SigningKey: signingKey,
|
|
Trust: id.TrustStateUnset,
|
|
Name: name,
|
|
Deleted: false,
|
|
}, nil
|
|
}
|