crypto: Initial support for private cross signing identities.

master
Damir Jelić 2020-10-14 15:35:06 +02:00
parent 3338ecf62a
commit c85fe6bc21
7 changed files with 635 additions and 9 deletions

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@ -31,7 +31,7 @@ docs = ["encryption", "sqlite_cryptostore", "messages"]
async-trait = "0.1.41" async-trait = "0.1.41"
dashmap = { version = "3.11.10", optional = true } dashmap = { version = "3.11.10", optional = true }
http = "0.2.1" http = "0.2.1"
serde_json = "1.0.58" serde_json = "1.0.59"
thiserror = "1.0.21" thiserror = "1.0.21"
tracing = "0.1.21" tracing = "0.1.21"
url = "2.1.1" url = "2.1.1"
@ -73,7 +73,7 @@ async-std = { version = "1.6.5", features = ["unstable"] }
dirs = "3.0.1" dirs = "3.0.1"
matrix-sdk-test = { version = "0.1.0", path = "../matrix_sdk_test" } matrix-sdk-test = { version = "0.1.0", path = "../matrix_sdk_test" }
tokio = { version = "0.2.22", features = ["rt-threaded", "macros"] } tokio = { version = "0.2.22", features = ["rt-threaded", "macros"] }
serde_json = "1.0.58" serde_json = "1.0.59"
tracing-subscriber = "0.2.13" tracing-subscriber = "0.2.13"
tempfile = "3.1.0" tempfile = "3.1.0"
mockito = "0.27.0" mockito = "0.27.0"

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@ -26,7 +26,7 @@ docs = ["encryption", "sqlite_cryptostore", "messages"]
[dependencies] [dependencies]
async-trait = "0.1.41" async-trait = "0.1.41"
serde = "1.0.116" serde = "1.0.116"
serde_json = "1.0.58" serde_json = "1.0.59"
zeroize = "1.1.1" zeroize = "1.1.1"
tracing = "0.1.21" tracing = "0.1.21"

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@ -28,7 +28,7 @@ matrix-sdk-common = { version = "0.1.0", path = "../matrix_sdk_common" }
olm-rs = { version = "1.0.0", features = ["serde"] } olm-rs = { version = "1.0.0", features = ["serde"] }
getrandom = "0.2.0" getrandom = "0.2.0"
serde = { version = "1.0.116", features = ["derive", "rc"] } serde = { version = "1.0.116", features = ["derive", "rc"] }
serde_json = "1.0.58" serde_json = "1.0.59"
cjson = "0.1.1" cjson = "0.1.1"
zeroize = { version = "1.1.1", features = ["zeroize_derive"] } zeroize = { version = "1.1.1", features = ["zeroize_derive"] }
url = "2.1.1" url = "2.1.1"
@ -39,6 +39,7 @@ tracing = "0.1.21"
atomic = "0.5.0" atomic = "0.5.0"
dashmap = "3.11.10" dashmap = "3.11.10"
sha2 = "0.9.1" sha2 = "0.9.1"
aes-gcm = "0.7.0"
aes-ctr = "0.5.0" aes-ctr = "0.5.0"
pbkdf2 = { version = "0.5.0", default-features = false } pbkdf2 = { version = "0.5.0", default-features = false }
hmac = "0.9.0" hmac = "0.9.0"
@ -60,7 +61,7 @@ features = ["runtime-tokio", "sqlite", "macros"]
tokio = { version = "0.2.22", features = ["rt-threaded", "macros"] } tokio = { version = "0.2.22", features = ["rt-threaded", "macros"] }
futures = "0.3.6" futures = "0.3.6"
proptest = "0.10.1" proptest = "0.10.1"
serde_json = "1.0.58" serde_json = "1.0.59"
tempfile = "3.1.0" tempfile = "3.1.0"
http = "0.2.1" http = "0.2.1"
matrix-sdk-test = { version = "0.1.0", path = "../matrix_sdk_test" } matrix-sdk-test = { version = "0.1.0", path = "../matrix_sdk_test" }

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@ -86,6 +86,24 @@ impl From<CrossSigningKey> for UserSigningPubkey {
} }
} }
impl Into<CrossSigningKey> for MasterPubkey {
fn into(self) -> CrossSigningKey {
self.0.as_ref().clone()
}
}
impl Into<CrossSigningKey> for UserSigningPubkey {
fn into(self) -> CrossSigningKey {
self.0.as_ref().clone()
}
}
impl Into<CrossSigningKey> for SelfSigningPubkey {
fn into(self) -> CrossSigningKey {
self.0.as_ref().clone()
}
}
impl AsRef<CrossSigningKey> for MasterPubkey { impl AsRef<CrossSigningKey> for MasterPubkey {
fn as_ref(&self) -> &CrossSigningKey { fn as_ref(&self) -> &CrossSigningKey {
&self.0 &self.0
@ -135,7 +153,7 @@ impl<'a> From<&'a UserSigningPubkey> for CrossSigningSubKeys<'a> {
} }
/// Enum over the cross signing sub-keys. /// Enum over the cross signing sub-keys.
enum CrossSigningSubKeys<'a> { pub(crate) enum CrossSigningSubKeys<'a> {
/// The self signing subkey. /// The self signing subkey.
SelfSigning(&'a SelfSigningPubkey), SelfSigning(&'a SelfSigningPubkey),
/// The user signing subkey. /// The user signing subkey.
@ -152,7 +170,7 @@ impl<'a> CrossSigningSubKeys<'a> {
} }
/// Get the `CrossSigningKey` from an sub-keys enum /// Get the `CrossSigningKey` from an sub-keys enum
fn cross_signing_key(&self) -> &CrossSigningKey { pub(crate) fn cross_signing_key(&self) -> &CrossSigningKey {
match self { match self {
CrossSigningSubKeys::SelfSigning(key) => &key.0, CrossSigningSubKeys::SelfSigning(key) => &key.0,
CrossSigningSubKeys::UserSigning(key) => &key.0, CrossSigningSubKeys::UserSigning(key) => &key.0,
@ -198,7 +216,7 @@ impl MasterPubkey {
/// ///
/// Returns an empty result if the signature check succeeded, otherwise a /// Returns an empty result if the signature check succeeded, otherwise a
/// SignatureError indicating why the check failed. /// SignatureError indicating why the check failed.
fn verify_subkey<'a>( pub(crate) fn verify_subkey<'a>(
&self, &self,
subkey: impl Into<CrossSigningSubKeys<'a>>, subkey: impl Into<CrossSigningSubKeys<'a>>,
) -> Result<(), SignatureError> { ) -> Result<(), SignatureError> {

View File

@ -20,6 +20,7 @@
mod account; mod account;
mod group_sessions; mod group_sessions;
mod session; mod session;
mod signing;
mod utility; mod utility;
pub(crate) use account::Account; pub(crate) use account::Account;

View File

@ -0,0 +1,606 @@
// 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.
#![allow(dead_code)]
use aes_gcm::{
aead::{generic_array::GenericArray, Aead, NewAead},
Aes256Gcm,
};
use base64::{decode_config, encode_config, DecodeError, URL_SAFE_NO_PAD};
use serde::{Deserialize, Serialize};
use std::{
collections::BTreeMap,
sync::{
atomic::{AtomicBool, Ordering},
Arc,
},
};
use zeroize::Zeroizing;
use olm_rs::{errors::OlmUtilityError, pk::OlmPkSigning, utility::OlmUtility, PicklingMode};
use matrix_sdk_common::{
api::r0::keys::{upload_signing_keys::Request as UploadRequest, CrossSigningKey, KeyUsage},
identifiers::UserId,
locks::Mutex,
};
use crate::identities::{MasterPubkey, SelfSigningPubkey, UserSigningPubkey};
fn encode<T: AsRef<[u8]>>(input: T) -> String {
encode_config(input, URL_SAFE_NO_PAD)
}
fn decode<T: AsRef<[u8]>>(input: T) -> Result<Vec<u8>, DecodeError> {
decode_config(input, URL_SAFE_NO_PAD)
}
#[derive(Clone)]
pub struct Signing {
inner: Arc<Mutex<OlmPkSigning>>,
seed: Arc<Zeroizing<Vec<u8>>>,
public_key: PublicSigningKey,
}
impl std::fmt::Debug for Signing {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
f.debug_struct("Signing")
.field("public_key", &self.public_key.as_str())
.finish()
}
}
impl PartialEq for Signing {
fn eq(&self, other: &Signing) -> bool {
self.seed == other.seed
}
}
#[derive(Clone, PartialEq, Debug)]
struct MasterSigning {
inner: Signing,
public_key: MasterPubkey,
}
#[derive(Debug, Clone, Deserialize, Serialize)]
struct PickledMasterSigning {
pickle: PickledSigning,
public_key: CrossSigningKey,
}
#[derive(Debug, Clone, Deserialize, Serialize)]
struct PickledUserSigning {
pickle: PickledSigning,
public_key: CrossSigningKey,
}
#[derive(Debug, Clone, Deserialize, Serialize)]
struct PickledSelfSigning {
pickle: PickledSigning,
public_key: CrossSigningKey,
}
impl MasterSigning {
async fn pickle(&self, pickle_mode: PicklingMode) -> PickledMasterSigning {
let pickle = self.inner.pickle(pickle_mode).await;
let public_key = self.public_key.clone().into();
PickledMasterSigning { pickle, public_key }
}
fn from_pickle(pickle: PickledMasterSigning, pickle_mode: PicklingMode) -> Self {
let inner = Signing::from_pickle(pickle.pickle, pickle_mode);
Self {
inner,
public_key: pickle.public_key.into(),
}
}
async fn sign_subkey<'a>(&self, subkey: &mut CrossSigningKey) {
// TODO create a borrowed version of a cross singing key.
let subkey_wihtout_signatures = CrossSigningKey {
user_id: subkey.user_id.clone(),
keys: subkey.keys.clone(),
usage: subkey.usage.clone(),
signatures: BTreeMap::new(),
};
let message = cjson::to_string(&subkey_wihtout_signatures)
.expect("Can't serialize cross signing subkey");
let signature = self.inner.sign(&message).await;
subkey
.signatures
.entry(self.public_key.user_id().to_owned())
.or_insert_with(BTreeMap::new)
.insert(
format!("ed25519:{}", self.inner.public_key().as_str()),
signature.0,
);
}
}
impl UserSigning {
async fn pickle(&self, pickle_mode: PicklingMode) -> PickledUserSigning {
let pickle = self.inner.pickle(pickle_mode).await;
let public_key = self.public_key.clone().into();
PickledUserSigning { pickle, public_key }
}
fn from_pickle(pickle: PickledUserSigning, pickle_mode: PicklingMode) -> Self {
let inner = Signing::from_pickle(pickle.pickle, pickle_mode);
Self {
inner,
public_key: pickle.public_key.into(),
}
}
}
impl SelfSigning {
async fn pickle(&self, pickle_mode: PicklingMode) -> PickledSelfSigning {
let pickle = self.inner.pickle(pickle_mode).await;
let public_key = self.public_key.clone().into();
PickledSelfSigning { pickle, public_key }
}
fn from_pickle(pickle: PickledSelfSigning, pickle_mode: PicklingMode) -> Self {
let inner = Signing::from_pickle(pickle.pickle, pickle_mode);
Self {
inner,
public_key: pickle.public_key.into(),
}
}
}
#[derive(Clone, PartialEq, Debug)]
struct SelfSigning {
inner: Signing,
public_key: SelfSigningPubkey,
}
#[derive(Clone, PartialEq, Debug)]
struct UserSigning {
inner: Signing,
public_key: UserSigningPubkey,
}
#[derive(Clone, Debug)]
pub struct PrivateCrossSigningIdentity {
user_id: Arc<UserId>,
shared: Arc<AtomicBool>,
master_key: Arc<Mutex<Option<MasterSigning>>>,
user_signing_key: Arc<Mutex<Option<UserSigning>>>,
self_signing_key: Arc<Mutex<Option<SelfSigning>>>,
}
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct PickledCrossSigningIdentity {
user_id: UserId,
shared: bool,
master_key: Option<PickledMasterSigning>,
user_signing_key: Option<PickledUserSigning>,
self_signing_key: Option<PickledSelfSigning>,
}
#[derive(Debug, Clone)]
pub struct Signature(String);
#[derive(Debug, Clone, Serialize, Deserialize)]
struct PickledSigning(String);
#[derive(Debug, Clone, Serialize, Deserialize)]
struct InnerPickle {
version: u8,
nonce: String,
ciphertext: String,
}
#[derive(Debug, Clone, PartialEq, Eq)]
struct PublicSigningKey(Arc<String>);
impl Signature {
fn as_str(&self) -> &str {
&self.0
}
}
impl PickledSigning {
fn as_str(&self) -> &str {
&self.0
}
}
impl PublicSigningKey {
fn as_str(&self) -> &str {
&self.0
}
fn to_string(&self) -> String {
self.0.to_string()
}
}
impl Signing {
fn new() -> Self {
let seed = OlmPkSigning::generate_seed();
Self::from_seed(seed)
}
fn from_seed(seed: Vec<u8>) -> Self {
let inner = OlmPkSigning::new(seed.clone()).expect("Unable to create pk signing object");
let public_key = PublicSigningKey(Arc::new(inner.public_key().to_owned()));
Signing {
inner: Arc::new(Mutex::new(inner)),
seed: Arc::new(Zeroizing::from(seed)),
public_key,
}
}
fn from_pickle(pickle: PickledSigning, pickle_mode: PicklingMode) -> Self {
let mode = if let PicklingMode::Encrypted { key } = &pickle_mode {
key
} else {
"DEFAULT_PICKLE_PASSPHRASE_123456".as_bytes()
};
let pickled: InnerPickle = serde_json::from_str(pickle.as_str()).unwrap();
let key = GenericArray::from_slice(mode);
let cipher = Aes256Gcm::new(key);
let nonce = decode(pickled.nonce).unwrap();
let nonce = GenericArray::from_slice(&nonce);
let ciphertext = &decode(pickled.ciphertext).unwrap();
let seed = cipher
.decrypt(&nonce, ciphertext.as_slice())
.expect("Can't decrypt pickle");
Self::from_seed(seed)
}
async fn pickle(&self, pickle_mode: PicklingMode) -> PickledSigning {
let mode = if let PicklingMode::Encrypted { key } = &pickle_mode {
key
} else {
"DEFAULT_PICKLE_PASSPHRASE_123456".as_bytes()
};
let key = GenericArray::from_slice(mode);
let cipher = Aes256Gcm::new(key);
let nonce = GenericArray::from_slice(b"unique nonce");
let ciphertext = cipher
.encrypt(nonce, self.seed.as_slice())
.expect("Can't encrypt signing pickle");
let ciphertext = encode(ciphertext);
let pickle = InnerPickle {
version: 1,
nonce: encode(nonce.as_slice()),
ciphertext,
};
PickledSigning(serde_json::to_string(&pickle).expect("Can't encode pickled signing"))
}
fn public_key(&self) -> &PublicSigningKey {
&self.public_key
}
fn cross_signing_key(&self, user_id: UserId, usage: KeyUsage) -> CrossSigningKey {
let mut keys = BTreeMap::new();
keys.insert(
format!("ed25519:{}", self.public_key().as_str()),
self.public_key().to_string(),
);
CrossSigningKey {
user_id,
usage: vec![usage],
keys,
signatures: BTreeMap::new(),
}
}
async fn verify(&self, message: &str, signature: &Signature) -> Result<bool, OlmUtilityError> {
let utility = OlmUtility::new();
utility.ed25519_verify(self.public_key.as_str(), message, signature.as_str())
}
async fn sign(&self, message: &str) -> Signature {
Signature(self.inner.lock().await.sign(message))
}
}
impl PrivateCrossSigningIdentity {
async fn new(user_id: UserId) -> Self {
let master = Signing::new();
let public_key = master.cross_signing_key(user_id.clone(), KeyUsage::Master);
let master = MasterSigning {
inner: master,
public_key: public_key.into(),
};
let user = Signing::new();
let mut public_key = user.cross_signing_key(user_id.clone(), KeyUsage::UserSigning);
master.sign_subkey(&mut public_key).await;
let user = UserSigning {
inner: user,
public_key: public_key.into(),
};
let self_signing = Signing::new();
let mut public_key = self_signing.cross_signing_key(user_id.clone(), KeyUsage::SelfSigning);
master.sign_subkey(&mut public_key).await;
let self_signing = SelfSigning {
inner: self_signing,
public_key: public_key.into(),
};
Self {
user_id: Arc::new(user_id),
shared: Arc::new(AtomicBool::new(false)),
master_key: Arc::new(Mutex::new(Some(master))),
self_signing_key: Arc::new(Mutex::new(Some(self_signing))),
user_signing_key: Arc::new(Mutex::new(Some(user))),
}
}
fn mark_as_shared(&self) {
self.shared.store(true, Ordering::SeqCst)
}
pub fn shared(&self) -> bool {
self.shared.load(Ordering::SeqCst)
}
async fn pickle(&self, pickle_mode: PicklingMode) -> PickledCrossSigningIdentity {
let pickle_key = if let PicklingMode::Encrypted { key } = &pickle_mode {
key
} else {
"DEFAULT_PICKLE_PASSPHRASE_123456".as_bytes()
}
.to_vec();
let master_key = if let Some(m) = self.master_key.lock().await.as_ref() {
Some(
m.pickle(PicklingMode::Encrypted {
key: pickle_key.clone(),
})
.await,
)
} else {
None
};
let self_signing_key = if let Some(m) = self.self_signing_key.lock().await.as_ref() {
Some(
m.pickle(PicklingMode::Encrypted {
key: pickle_key.clone(),
})
.await,
)
} else {
None
};
let user_signing_key = if let Some(m) = self.user_signing_key.lock().await.as_ref() {
Some(
m.pickle(PicklingMode::Encrypted {
key: pickle_key.clone(),
})
.await,
)
} else {
None
};
PickledCrossSigningIdentity {
user_id: self.user_id.as_ref().to_owned(),
shared: self.shared(),
master_key,
self_signing_key,
user_signing_key,
}
}
async fn from_pickle(pickle: PickledCrossSigningIdentity, pickle_mode: PicklingMode) -> Self {
let pickle_key = if let PicklingMode::Encrypted { key } = &pickle_mode {
key
} else {
"DEFAULT_PICKLE_PASSPHRASE_123456".as_bytes()
}
.to_vec();
let master = if let Some(m) = pickle.master_key {
Some(MasterSigning::from_pickle(
m,
PicklingMode::Encrypted {
key: pickle_key.clone(),
},
))
} else {
None
};
let self_signing = if let Some(s) = pickle.self_signing_key {
Some(SelfSigning::from_pickle(
s,
PicklingMode::Encrypted {
key: pickle_key.clone(),
},
))
} else {
None
};
let user_signing = if let Some(u) = pickle.user_signing_key {
Some(UserSigning::from_pickle(
u,
PicklingMode::Encrypted { key: pickle_key },
))
} else {
None
};
Self {
user_id: Arc::new(pickle.user_id),
shared: Arc::new(AtomicBool::from(pickle.shared)),
master_key: Arc::new(Mutex::new(master)),
self_signing_key: Arc::new(Mutex::new(self_signing)),
user_signing_key: Arc::new(Mutex::new(user_signing)),
}
}
async fn as_upload_request(&self) -> UploadRequest<'_> {
UploadRequest {
auth: None,
master_key: self
.master_key
.lock()
.await
.as_ref()
.cloned()
.map(|k| k.public_key.into()),
user_signing_key: self
.user_signing_key
.lock()
.await
.as_ref()
.cloned()
.map(|k| k.public_key.into()),
self_signing_key: self
.self_signing_key
.lock()
.await
.as_ref()
.cloned()
.map(|k| k.public_key.into()),
}
}
}
#[cfg(test)]
mod test {
use super::{PrivateCrossSigningIdentity, Signing};
use matrix_sdk_common::identifiers::{user_id, UserId};
use matrix_sdk_test::async_test;
use olm_rs::PicklingMode;
fn user_id() -> UserId {
user_id!("@example:localhost")
}
#[test]
fn signing_creation() {
let signing = Signing::new();
assert!(!signing.public_key().as_str().is_empty());
}
#[async_test]
async fn signature_verification() {
let signing = Signing::new();
let message = "Hello world";
let signature = signing.sign(message).await;
assert!(signing.verify(message, &signature).await.is_ok());
}
#[async_test]
async fn pickling_signing() {
let signing = Signing::new();
let pickled = signing.pickle(PicklingMode::Unencrypted).await;
let unpickled = Signing::from_pickle(pickled, PicklingMode::Unencrypted);
assert_eq!(signing.public_key(), unpickled.public_key());
}
#[async_test]
async fn private_identity_creation() {
let identity = PrivateCrossSigningIdentity::new(user_id()).await;
assert!(identity
.master_key
.lock()
.await
.as_ref()
.unwrap()
.public_key
.verify_subkey(
&identity
.self_signing_key
.lock()
.await
.as_ref()
.unwrap()
.public_key,
)
.is_ok());
assert!(identity
.master_key
.lock()
.await
.as_ref()
.unwrap()
.public_key
.verify_subkey(
&identity
.user_signing_key
.lock()
.await
.as_ref()
.unwrap()
.public_key,
)
.is_ok());
}
#[async_test]
async fn identity_pickling() {
let identity = PrivateCrossSigningIdentity::new(user_id()).await;
let pickled = identity.pickle(PicklingMode::Unencrypted).await;
let unpickled =
PrivateCrossSigningIdentity::from_pickle(pickled, PicklingMode::Unencrypted).await;
assert_eq!(identity.user_id, unpickled.user_id);
assert_eq!(
&*identity.master_key.lock().await,
&*unpickled.master_key.lock().await
);
assert_eq!(
&*identity.user_signing_key.lock().await,
&*unpickled.user_signing_key.lock().await
);
assert_eq!(
&*identity.self_signing_key.lock().await,
&*unpickled.self_signing_key.lock().await
);
}
}

View File

@ -11,7 +11,7 @@ repository = "https://github.com/matrix-org/matrix-rust-sdk"
version = "0.1.0" version = "0.1.0"
[dependencies] [dependencies]
serde_json = "1.0.58" serde_json = "1.0.59"
http = "0.2.1" http = "0.2.1"
matrix-sdk-common = { version = "0.1.0", path = "../matrix_sdk_common" } matrix-sdk-common = { version = "0.1.0", path = "../matrix_sdk_common" }
matrix-sdk-test-macros = { version = "0.1.0", path = "../matrix_sdk_test_macros" } matrix-sdk-test-macros = { version = "0.1.0", path = "../matrix_sdk_test_macros" }