matrix_sdk_crypto/
error.rs

1// Copyright 2020 The Matrix.org Foundation C.I.C.
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15use std::collections::BTreeMap;
16
17use matrix_sdk_common::deserialized_responses::{VerificationLevel, WithheldCode};
18use ruma::{CanonicalJsonError, IdParseError, OwnedDeviceId, OwnedRoomId, OwnedUserId};
19use serde::{Serializer, ser::SerializeMap};
20use serde_json::Error as SerdeError;
21use thiserror::Error;
22use vodozemac::{Curve25519PublicKey, Ed25519PublicKey};
23
24use super::store::CryptoStoreError;
25#[cfg(doc)]
26use crate::{CollectStrategy, Device, LocalTrust, OtherUserIdentity};
27use crate::{olm::SessionExportError, types::SignedKey};
28
29pub type OlmResult<T> = Result<T, OlmError>;
30pub type MegolmResult<T> = Result<T, MegolmError>;
31
32/// Error representing a failure during a device to device cryptographic
33/// operation.
34#[derive(Error, Debug)]
35pub enum OlmError {
36    /// The event that should have been decrypted is malformed.
37    #[error(transparent)]
38    EventError(#[from] EventError),
39
40    /// The received decrypted event couldn't be deserialized.
41    #[error(transparent)]
42    JsonError(#[from] SerdeError),
43
44    /// The received room key couldn't be converted into a valid Megolm session.
45    #[error(transparent)]
46    SessionCreation(#[from] SessionCreationError),
47
48    /// The room key that should be exported can't be converted into a
49    /// `m.forwarded_room_key` event.
50    #[error(transparent)]
51    SessionExport(#[from] SessionExportError),
52
53    /// The storage layer returned an error.
54    #[error("failed to read or write to the crypto store {0}")]
55    Store(#[from] CryptoStoreError),
56
57    /// The session with a device has become corrupted.
58    #[error(
59        "decryption failed likely because an Olm session from {0} with sender key {1} was wedged"
60    )]
61    SessionWedged(OwnedUserId, Curve25519PublicKey),
62
63    /// An Olm message got replayed while the Olm ratchet has already moved
64    /// forward.
65    #[error("decryption failed because an Olm message from {0} with sender key {1} was replayed")]
66    ReplayedMessage(OwnedUserId, Curve25519PublicKey),
67
68    /// Encryption failed because the device does not have a valid Olm session
69    /// with us.
70    #[error(
71        "encryption failed because the device does not \
72            have a valid Olm session with us"
73    )]
74    MissingSession,
75
76    /// Encrypting of an Olm message failed because of a low-level cryptographic
77    /// issue occurred.
78    #[error(transparent)]
79    Encryption(#[from] vodozemac::olm::EncryptionError),
80
81    /// Encryption failed due to an error collecting the recipient devices.
82    #[error("encryption failed due to an error collecting the recipient devices: {0}")]
83    SessionRecipientCollectionError(SessionRecipientCollectionError),
84
85    /// Encrypted content is withheld from this device
86    #[error("encryption content is withheld from this: {0}")]
87    Withheld(WithheldCode),
88
89    /// Refused to decrypt because the sender was not verified or did not meet
90    /// the required VerificationLevel.
91    #[error(
92        "refusing to decrypt the event because the sender device was not \
93        verified and 'exclude insecure devices' is enabled."
94    )]
95    UnverifiedSenderDevice,
96}
97
98/// Error representing a failure during a group encryption operation.
99#[derive(Error, Debug)]
100pub enum MegolmError {
101    /// The event that should have been decrypted is malformed.
102    #[error(transparent)]
103    EventError(#[from] EventError),
104
105    /// The received decrypted event couldn't be deserialized.
106    #[error(transparent)]
107    JsonError(#[from] SerdeError),
108
109    /// Decryption failed because we're missing the room key that was used to
110    /// encrypt the event.
111    #[error("Can't find the room key to decrypt the event, withheld code: {0:?}")]
112    MissingRoomKey(Option<WithheldCode>),
113
114    /// Decryption failed because of a mismatch between the identity keys of the
115    /// device we received the room key from and the identity keys recorded in
116    /// the plaintext of the room key to-device message.
117    #[error(
118        "decryption failed because of mismatched identity keys of the sending device and those recorded in the to-device message"
119    )]
120    MismatchedIdentityKeys(MismatchedIdentityKeysError),
121
122    /// The encrypted megolm message couldn't be decoded.
123    #[error(transparent)]
124    Decode(#[from] vodozemac::DecodeError),
125
126    /// The event could not have been decrypted.
127    #[error(transparent)]
128    Decryption(#[from] vodozemac::megolm::DecryptionError),
129
130    /// The storage layer returned an error.
131    #[error(transparent)]
132    Store(#[from] CryptoStoreError),
133
134    /// An encrypted message wasn't decrypted, because the sender's
135    /// cross-signing identity did not satisfy the requested
136    /// [`crate::TrustRequirement`].
137    ///
138    /// The nested value is the sender's current verification level.
139    #[error("decryption failed because trust requirement not satisfied: {0}")]
140    SenderIdentityNotTrusted(VerificationLevel),
141
142    /// The outer state key could not be verified against the inner encrypted
143    /// state key and type.
144    #[cfg(feature = "experimental-encrypted-state-events")]
145    #[error("decryption failed because the state key failed to validate")]
146    StateKeyVerificationFailed,
147}
148
149/// Decryption failed because of a mismatch between the identity keys of the
150/// device we received the room key from and the identity keys recorded in
151/// the plaintext of the room key to-device message.
152#[derive(Error, Debug, PartialEq)]
153pub struct MismatchedIdentityKeysError {
154    /// The Ed25519 key recorded in the room key's to-device message.
155    pub key_ed25519: Box<Ed25519PublicKey>,
156    /// The Ed25519 identity key of the device sending the room key.
157    pub device_ed25519: Option<Box<Ed25519PublicKey>>,
158    /// The Curve25519 key recorded in the room key's to-device message.
159    pub key_curve25519: Box<Curve25519PublicKey>,
160    /// The Curve25519 identity key of the device sending the room key.
161    pub device_curve25519: Option<Box<Curve25519PublicKey>>,
162}
163
164impl std::fmt::Display for MismatchedIdentityKeysError {
165    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
166        let mut ser = f.serialize_struct("MismatchedIdentityKeysError", 4)?;
167        ser.serialize_entry("key_ed25519", &self.key_ed25519)?;
168        ser.serialize_entry("device_ed25519", &self.device_ed25519)?;
169        ser.serialize_entry("key_curve25519", &self.key_curve25519)?;
170        ser.serialize_entry("device_curve25519", &self.device_curve25519)?;
171        ser.end()
172    }
173}
174
175impl From<MismatchedIdentityKeysError> for MegolmError {
176    fn from(value: MismatchedIdentityKeysError) -> Self {
177        MegolmError::MismatchedIdentityKeys(value)
178    }
179}
180
181impl From<MismatchedIdentityKeysError> for SessionCreationError {
182    fn from(value: MismatchedIdentityKeysError) -> Self {
183        SessionCreationError::MismatchedIdentityKeys(value)
184    }
185}
186
187/// Error that occurs when decrypting an event that is malformed.
188#[derive(Error, Debug)]
189pub enum EventError {
190    /// The Encrypted message has been encrypted with a unsupported algorithm.
191    #[error("the Encrypted message has been encrypted with a unsupported algorithm.")]
192    UnsupportedAlgorithm,
193
194    /// The provided JSON value isn't an object.
195    #[error("the provided JSON value isn't an object")]
196    NotAnObject,
197
198    /// The Encrypted message doesn't contain a ciphertext for our device.
199    #[error("the Encrypted message doesn't contain a ciphertext for our device")]
200    MissingCiphertext,
201
202    /// The Encrypted message is missing the signing key of the sender.
203    #[error("the Encrypted message is missing the signing key of the sender")]
204    MissingSigningKey,
205
206    /// The Encrypted message is missing the sender key.
207    #[error("the Encrypted message is missing the sender key")]
208    MissingSenderKey,
209
210    /// The sender of the plaintext doesn't match the sender of the encrypted
211    /// message.
212    #[error(
213        "the sender of the plaintext doesn't match the sender of the encrypted \
214        message, got {0}, expected {1}"
215    )]
216    MismatchedSender(OwnedUserId, OwnedUserId),
217
218    /// The public key that was part of the message doesn't match the key we
219    /// have stored.
220    #[error(
221        "the public key that was part of the message doesn't match the key we \
222        have stored, expected {0}, got {1}"
223    )]
224    MismatchedKeys(Box<Ed25519PublicKey>, Box<Ed25519PublicKey>),
225
226    /// The room ID of the room key doesn't match the room ID of the decrypted
227    /// event.
228    #[error(
229        "the room id of the room key doesn't match the room id of the \
230        decrypted event: expected {0}, got {1:?}"
231    )]
232    MismatchedRoom(OwnedRoomId, Option<OwnedRoomId>),
233
234    /// The event includes `sender_device_keys` as per [MSC4147], but the
235    /// signature was invalid, or the ed25519 or curve25519 key did not
236    /// match other data in the event.
237    ///
238    /// [MSC4147]: https://github.com/matrix-org/matrix-spec-proposals/pull/4147
239    #[error("the event included sender_device_keys which were invalid in some way")]
240    InvalidSenderDeviceKeys,
241}
242
243/// Error type describing different errors that can happen when we create an
244/// Olm session from a pickle.
245#[derive(Error, Debug)]
246pub enum SessionUnpickleError {
247    /// The device keys are missing the signing key
248    #[error("the device keys are missing the signing key")]
249    MissingSigningKey,
250
251    /// The device keys are missing the identity key
252    #[error("the device keys are missing the identity key")]
253    MissingIdentityKey,
254}
255
256/// Error type describing different errors that happen when we check or create
257/// signatures for a Matrix JSON object.
258#[derive(Error, Debug)]
259pub enum SignatureError {
260    /// The signature was made using an unsupported algorithm.
261    #[error("the signature used an unsupported algorithm")]
262    UnsupportedAlgorithm,
263
264    /// The ID of the signing key isn't a valid key ID.
265    #[error("the ID of the signing key is invalid")]
266    InvalidKeyId(#[from] IdParseError),
267
268    /// The signing key that should create or check a signature is missing.
269    #[error("the signing key is missing from the object that signed the message")]
270    MissingSigningKey,
271
272    /// The user id of signing key differs from the user id that provided the
273    /// signature.
274    #[error("the user id of the signing key differs user id that provided the signature")]
275    UserIdMismatch,
276
277    /// The provided JSON value that was signed and the signature should be
278    /// checked isn't a valid JSON object.
279    #[error("the provided JSON value isn't an object")]
280    NotAnObject,
281
282    /// The provided JSON value that was signed and the signature should be
283    /// checked isn't a valid JSON object.
284    #[error("the provided JSON object doesn't contain a signatures field")]
285    NoSignatureFound,
286
287    /// The signature couldn't be verified.
288    #[error(transparent)]
289    VerificationError(#[from] vodozemac::SignatureError),
290
291    /// The public key isn't a valid ed25519 key.
292    #[error(transparent)]
293    InvalidKey(#[from] vodozemac::KeyError),
294
295    /// The signature could not be decoded.
296    #[error("the given signature is not valid and can't be decoded")]
297    InvalidSignature,
298
299    /// The signing key that used to sign the object has been changed.
300    #[error("the signing key that used to sign the object has changed, old: {0:?}, new: {1:?}")]
301    SigningKeyChanged(Option<Box<Ed25519PublicKey>>, Option<Box<Ed25519PublicKey>>),
302
303    /// The signed object couldn't be deserialized.
304    #[error(transparent)]
305    JsonError(#[from] CanonicalJsonError),
306
307    /// The store ran into an error.
308    #[error(transparent)]
309    StoreError(#[from] CryptoStoreError),
310}
311
312/// Error that occurs when a room key can't be converted into a valid Megolm
313/// session.
314#[derive(Error, Debug)]
315pub enum SessionCreationError {
316    /// The requested one-time key isn't a signed curve key.
317    #[error(
318        "Failed to create a new Olm session for {0} {1}, the requested \
319        one-time key isn't a signed curve key"
320    )]
321    OneTimeKeyNotSigned(OwnedUserId, OwnedDeviceId),
322
323    /// The signed one-time key is missing.
324    #[error(
325        "Tried to create a new Olm session for {0} {1}, but the signed \
326        one-time key is missing"
327    )]
328    OneTimeKeyMissing(OwnedUserId, OwnedDeviceId),
329
330    /// Failed to verify the one-time key signatures.
331    #[error(
332        "Failed to verify the signature of a one-time key, key: {one_time_key:?}, \
333        signing_key: {signing_key:?}: {error:?}"
334    )]
335    InvalidSignature {
336        /// The one-time key that failed the signature verification.
337        one_time_key: Box<SignedKey>,
338        /// The key that was used to verify the signature.
339        signing_key: Option<Box<Ed25519PublicKey>>,
340        /// The exact error describing why the signature verification failed.
341        error: Box<SignatureError>,
342    },
343
344    /// The user's device is missing a curve25519 key.
345    #[error(
346        "Tried to create an Olm session for {0} {1}, but the device is missing \
347        a curve25519 key"
348    )]
349    DeviceMissingCurveKey(OwnedUserId, OwnedDeviceId),
350
351    /// Error deserializing the one-time key.
352    #[error("Error deserializing the one-time key: {0}")]
353    InvalidJson(#[from] serde_json::Error),
354
355    /// The given curve25519 key is not a valid key.
356    #[error("The given curve25519 key is not a valid key")]
357    InvalidCurveKey(#[from] vodozemac::KeyError),
358
359    /// Error when creating an Olm Session from an incoming Olm message.
360    #[error(transparent)]
361    InboundCreation(#[from] vodozemac::olm::SessionCreationError),
362
363    /// The given device keys are invalid.
364    #[error("The given device keys are invalid")]
365    InvalidDeviceKeys(#[from] SignatureError),
366
367    /// There was a mismatch between the identity keys of the device we received
368    /// the room key from and the identity keys recorded in the plaintext of the
369    /// room key to-device message.
370    #[error(
371        "There was a mismatch between the identity keys of the sending device \
372        and those recorded in the to-device message"
373    )]
374    MismatchedIdentityKeys(MismatchedIdentityKeysError),
375}
376
377/// Errors that can be returned by
378/// [`crate::machine::OlmMachine::set_room_settings`].
379#[derive(Debug, Error)]
380pub enum SetRoomSettingsError {
381    /// The changes are rejected because they conflict with the previous
382    /// settings for this room.
383    #[error("the new settings would cause a downgrade of encryption security")]
384    EncryptionDowngrade,
385
386    /// The changes are rejected because we would be unable to use them to
387    /// encrypt events.
388    #[error("the new settings are invalid")]
389    InvalidSettings,
390
391    /// The store ran into an error.
392    #[error(transparent)]
393    Store(#[from] CryptoStoreError),
394}
395
396/// Error representing a problem when collecting the recipient devices for the
397/// room key, during an encryption operation.
398#[derive(Error, Debug)]
399pub enum SessionRecipientCollectionError {
400    /// One or more verified users has one or more unsigned devices.
401    ///
402    /// Happens only with [`CollectStrategy::ErrorOnVerifiedUserProblem`].
403    ///
404    /// In order to resolve this, the caller can set the trust level of the
405    /// affected devices to [`LocalTrust::Ignored`] or
406    /// [`LocalTrust::BlackListed`] (see [`Device::set_local_trust`]), and
407    /// then retry the encryption operation.
408    #[error("one or more verified users have unsigned devices")]
409    VerifiedUserHasUnsignedDevice(BTreeMap<OwnedUserId, Vec<OwnedDeviceId>>),
410
411    /// One or more users was previously verified, but they have changed their
412    /// identity.
413    ///
414    /// Happens only with [`CollectStrategy::ErrorOnVerifiedUserProblem`] or
415    /// [`CollectStrategy::IdentityBasedStrategy`].
416    ///
417    /// In order to resolve this, the user can:
418    ///
419    /// * re-verify the problematic recipients, or
420    ///
421    /// * withdraw verification of the problematic recipients with
422    ///   [`OtherUserIdentity::withdraw_verification`], or
423    ///
424    /// * set the trust level of all of the devices belonging to the problematic
425    ///   recipients to [`LocalTrust::Ignored`] or [`LocalTrust::BlackListed`]
426    ///   (see [`Device::set_local_trust`]).
427    ///
428    /// The caller can then retry the encryption operation.
429    #[error("one or more users that were verified have changed their identity")]
430    VerifiedUserChangedIdentity(Vec<OwnedUserId>),
431
432    /// Cross-signing has not been configured on our own identity.
433    ///
434    /// Happens only with [`CollectStrategy::IdentityBasedStrategy`].
435    /// (Cross-signing is required for encryption when using
436    /// `IdentityBasedStrategy`.) Apps should detect this condition and prevent
437    /// sending in the UI rather than waiting for this error to be returned when
438    /// encrypting.
439    #[error("Encryption failed because cross-signing is not set up on your account")]
440    CrossSigningNotSetup,
441
442    /// The current device has not been cross-signed by our own identity.
443    ///
444    /// Happens only with [`CollectStrategy::IdentityBasedStrategy`].
445    /// (Cross-signing is required for encryption when using
446    /// `IdentityBasedStrategy`.) Apps should detect this condition and prevent
447    /// sending in the UI rather than waiting for this error to be returned when
448    /// encrypting.
449    #[error("Encryption failed because your device is not verified")]
450    SendingFromUnverifiedDevice,
451}
452
453/// Error representing a problem when pushing a secret
454#[derive(Error, Debug)]
455#[cfg(feature = "experimental-push-secrets")]
456pub enum SecretPushError {
457    #[error("The requested secret is not available")]
458    MissingSecret,
459
460    /// The storage layer returned an error.
461    #[error(transparent)]
462    StoreError(#[from] CryptoStoreError),
463}
matrix_sdk_crypto/error.rs

matrix_sdk_crypto/
error.rs
