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//! Functions for signing and verifying JSON and events.
use std::{
borrow::Cow,
collections::{BTreeMap, BTreeSet},
mem,
};
use base64::{alphabet, Engine};
use ruma_common::{
canonical_json::{redact, JsonType},
serde::{base64::Standard, Base64},
CanonicalJsonObject, CanonicalJsonValue, OwnedEventId, OwnedServerName, RoomVersionId, UserId,
};
use serde_json::{from_str as from_json_str, to_string as to_json_string};
use sha2::{digest::Digest, Sha256};
use crate::{
keys::{KeyPair, PublicKeyMap},
split_id,
verification::{Ed25519Verifier, Verified, Verifier},
Error, JsonError, ParseError, VerificationError,
};
const MAX_PDU_BYTES: usize = 65_535;
/// The fields to remove from a JSON object when converting JSON into the "canonical" form.
static CANONICAL_JSON_FIELDS_TO_REMOVE: &[&str] = &["signatures", "unsigned"];
/// The fields to remove from a JSON object when creating a content hash of an event.
static CONTENT_HASH_FIELDS_TO_REMOVE: &[&str] = &["hashes", "signatures", "unsigned"];
/// The fields to remove from a JSON object when creating a reference hash of an event.
static REFERENCE_HASH_FIELDS_TO_REMOVE: &[&str] = &["signatures", "unsigned"];
/// Signs an arbitrary JSON object and adds the signature to an object under the key `signatures`.
///
/// If `signatures` is already present, the new signature will be appended to the existing ones.
///
/// # Parameters
///
/// * entity_id: The identifier of the entity creating the signature. Generally this means a
/// homeserver, e.g. "example.com".
/// * key_pair: A cryptographic key pair used to sign the JSON.
/// * object: A JSON object to sign according and append a signature to.
///
/// # Errors
///
/// Returns an error if:
///
/// * `object` contains a field called `signatures` that is not a JSON object.
///
/// # Examples
///
/// A homeserver signs JSON with a key pair:
///
/// ```rust
/// # use ruma_common::serde::base64::Base64;
/// #
/// const PKCS8: &str = "\
/// MFECAQEwBQYDK2VwBCIEINjozvdfbsGEt6DD+7Uf4PiJ/YvTNXV2mIPc/\
/// tA0T+6tgSEA3TPraTczVkDPTRaX4K+AfUuyx7Mzq1UafTXypnl0t2k\
/// ";
///
/// let document: Base64 = Base64::parse(PKCS8).unwrap();
///
/// // Create an Ed25519 key pair.
/// let key_pair = ruma_signatures::Ed25519KeyPair::from_der(
/// document.as_bytes(),
/// "1".into(), // The "version" of the key.
/// )
/// .unwrap();
///
/// // Deserialize some JSON.
/// let mut value = serde_json::from_str("{}").unwrap();
///
/// // Sign the JSON with the key pair.
/// assert!(ruma_signatures::sign_json("domain", &key_pair, &mut value).is_ok());
/// ```
///
/// This will modify the JSON from an empty object to a structure like this:
///
/// ```json
/// {
/// "signatures": {
/// "domain": {
/// "ed25519:1": "K8280/U9SSy9IVtjBuVeLr+HpOB4BQFWbg+UZaADMtTdGYI7Geitb76LTrr5QV/7Xg4ahLwYGYZzuHGZKM5ZAQ"
/// }
/// }
/// }
/// ```
pub fn sign_json<K>(
entity_id: &str,
key_pair: &K,
object: &mut CanonicalJsonObject,
) -> Result<(), Error>
where
K: KeyPair,
{
let (signatures_key, mut signature_map) = match object.remove_entry("signatures") {
Some((key, CanonicalJsonValue::Object(signatures))) => (Cow::Owned(key), signatures),
Some(_) => return Err(JsonError::not_of_type("signatures", JsonType::Object)),
None => (Cow::Borrowed("signatures"), BTreeMap::new()),
};
let maybe_unsigned_entry = object.remove_entry("unsigned");
// Get the canonical JSON string.
let json = to_json_string(object).map_err(JsonError::Serde)?;
// Sign the canonical JSON string.
let signature = key_pair.sign(json.as_bytes());
// Insert the new signature in the map we pulled out (or created) previously.
let signature_set = signature_map
.entry(entity_id.to_owned())
.or_insert_with(|| CanonicalJsonValue::Object(BTreeMap::new()));
let signature_set = match signature_set {
CanonicalJsonValue::Object(obj) => obj,
_ => return Err(JsonError::not_multiples_of_type("signatures", JsonType::Object)),
};
signature_set.insert(signature.id(), CanonicalJsonValue::String(signature.base64()));
// Put `signatures` and `unsigned` back in.
object.insert(signatures_key.into(), CanonicalJsonValue::Object(signature_map));
if let Some((k, v)) = maybe_unsigned_entry {
object.insert(k, v);
}
Ok(())
}
/// Converts an event into the [canonical] string form.
///
/// [canonical]: https://spec.matrix.org/latest/appendices/#canonical-json
///
/// # Parameters
///
/// * object: The JSON object to convert.
///
/// # Examples
///
/// ```rust
/// let input = r#"{
/// "本": 2,
/// "日": 1
/// }"#;
///
/// let object = serde_json::from_str(input).unwrap();
/// let canonical = ruma_signatures::canonical_json(&object).unwrap();
///
/// assert_eq!(canonical, r#"{"日":1,"本":2}"#);
/// ```
pub fn canonical_json(object: &CanonicalJsonObject) -> Result<String, Error> {
canonical_json_with_fields_to_remove(object, CANONICAL_JSON_FIELDS_TO_REMOVE)
}
/// Uses a set of public keys to verify a signed JSON object.
///
/// Unlike `content_hash` and `reference_hash`, this function does not report an error if the
/// canonical JSON is larger than 65535 bytes; this function may be used for requests that are
/// larger than just one PDU's maximum size.
///
/// # Parameters
///
/// * public_key_map: A map from entity identifiers to a map from key identifiers to public keys.
/// Generally, entity identifiers are server names — the host/IP/port of a homeserver (e.g.
/// "example.com") for which a signature must be verified. Key identifiers for each server (e.g.
/// "ed25519:1") then map to their respective public keys.
/// * object: The JSON object that was signed.
///
/// # Errors
///
/// Returns an error if verification fails.
///
/// # Examples
///
/// ```rust
/// use std::collections::BTreeMap;
///
/// use ruma_common::serde::Base64;
///
/// const PUBLIC_KEY: &[u8] = b"XGX0JRS2Af3be3knz2fBiRbApjm2Dh61gXDJA8kcJNI";
///
/// // Deserialize the signed JSON.
/// let object = serde_json::from_str(
/// r#"{
/// "signatures": {
/// "domain": {
/// "ed25519:1": "K8280/U9SSy9IVtjBuVeLr+HpOB4BQFWbg+UZaADMtTdGYI7Geitb76LTrr5QV/7Xg4ahLwYGYZzuHGZKM5ZAQ"
/// }
/// }
/// }"#
/// ).unwrap();
///
/// // Create the `PublicKeyMap` that will inform `verify_json` which signatures to verify.
/// let mut public_key_set = BTreeMap::new();
/// public_key_set.insert("ed25519:1".into(), Base64::parse(PUBLIC_KEY.to_owned()).unwrap());
/// let mut public_key_map = BTreeMap::new();
/// public_key_map.insert("domain".into(), public_key_set);
///
/// // Verify at least one signature for each entity in `public_key_map`.
/// assert!(ruma_signatures::verify_json(&public_key_map, &object).is_ok());
/// ```
pub fn verify_json(
public_key_map: &PublicKeyMap,
object: &CanonicalJsonObject,
) -> Result<(), Error> {
let signature_map = match object.get("signatures") {
Some(CanonicalJsonValue::Object(signatures)) => signatures.clone(),
Some(_) => return Err(JsonError::not_of_type("signatures", JsonType::Object)),
None => return Err(JsonError::field_missing_from_object("signatures")),
};
for (entity_id, signature_set) in signature_map {
let signature_set = match signature_set {
CanonicalJsonValue::Object(set) => set,
_ => return Err(JsonError::not_multiples_of_type("signature sets", JsonType::Object)),
};
let public_keys = match public_key_map.get(&entity_id) {
Some(keys) => keys,
None => {
return Err(JsonError::key_missing("public_key_map", "public_keys", &entity_id))
}
};
for (key_id, signature) in &signature_set {
let signature = match signature {
CanonicalJsonValue::String(s) => s,
_ => return Err(JsonError::not_of_type("signature", JsonType::String)),
};
let public_key = public_keys.get(key_id).ok_or_else(|| {
JsonError::key_missing(
format!("public_keys of {}", &entity_id),
"signature",
key_id,
)
})?;
let signature = Base64::<Standard>::parse(signature)
.map_err(|e| ParseError::base64("signature", signature, e))?;
verify_json_with(
&Ed25519Verifier,
public_key.as_bytes(),
signature.as_bytes(),
object,
)?;
}
}
Ok(())
}
/// Uses a public key to verify a signed JSON object.
///
/// # Parameters
///
/// * verifier: A `Verifier` appropriate for the digital signature algorithm that was used.
/// * public_key: The raw bytes of the public key used to sign the JSON.
/// * signature: The raw bytes of the signature.
/// * object: The JSON object that was signed.
///
/// # Errors
///
/// Returns an error if verification fails.
fn verify_json_with<V>(
verifier: &V,
public_key: &[u8],
signature: &[u8],
object: &CanonicalJsonObject,
) -> Result<(), Error>
where
V: Verifier,
{
verifier.verify_json(public_key, signature, canonical_json(object)?.as_bytes())
}
/// Creates a *content hash* for an event.
///
/// The content hash of an event covers the complete event including the unredacted contents. It is
/// used during federation and is described in the Matrix server-server specification.
///
/// # Parameters
///
/// object: A JSON object to generate a content hash for.
///
/// # Errors
///
/// Returns an error if the event is too large.
pub fn content_hash(object: &CanonicalJsonObject) -> Result<Base64<Standard, [u8; 32]>, Error> {
let json = canonical_json_with_fields_to_remove(object, CONTENT_HASH_FIELDS_TO_REMOVE)?;
if json.len() > MAX_PDU_BYTES {
return Err(Error::PduSize);
}
let hash = Sha256::digest(json.as_bytes());
Ok(Base64::new(hash.into()))
}
/// Creates a *reference hash* for an event.
///
/// Returns the hash as a base64-encoded string, using the standard character set, without padding.
///
/// The reference hash of an event covers the essential fields of an event, including content
/// hashes. It is used to generate event identifiers and is described in the Matrix server-server
/// specification.
///
/// # Parameters
///
/// object: A JSON object to generate a reference hash for.
///
/// # Errors
///
/// Returns an error if the event is too large or redaction fails.
pub fn reference_hash(
value: &CanonicalJsonObject,
version: &RoomVersionId,
) -> Result<String, Error> {
let redacted_value = redact(value.clone(), version, None)?;
let json =
canonical_json_with_fields_to_remove(&redacted_value, REFERENCE_HASH_FIELDS_TO_REMOVE)?;
if json.len() > MAX_PDU_BYTES {
return Err(Error::PduSize);
}
let hash = Sha256::digest(json.as_bytes());
let base64_alphabet = match version {
RoomVersionId::V1 | RoomVersionId::V2 | RoomVersionId::V3 => alphabet::STANDARD,
// Room versions higher than version 3 are url safe base64 encoded
_ => alphabet::URL_SAFE,
};
let base64_engine = base64::engine::GeneralPurpose::new(
&base64_alphabet,
base64::engine::general_purpose::NO_PAD,
);
Ok(base64_engine.encode(hash))
}
/// Hashes and signs an event and adds the hash and signature to objects under the keys `hashes` and
/// `signatures`, respectively.
///
/// If `hashes` and/or `signatures` are already present, the new data will be appended to the
/// existing data.
///
/// # Parameters
///
/// * entity_id: The identifier of the entity creating the signature. Generally this means a
/// homeserver, e.g. "example.com".
/// * key_pair: A cryptographic key pair used to sign the event.
/// * object: A JSON object to be hashed and signed according to the Matrix specification.
///
/// # Errors
///
/// Returns an error if:
///
/// * `object` contains a field called `content` that is not a JSON object.
/// * `object` contains a field called `hashes` that is not a JSON object.
/// * `object` contains a field called `signatures` that is not a JSON object.
/// * `object` is missing the `type` field or the field is not a JSON string.
///
/// # Examples
///
/// ```rust
/// # use ruma_common::{RoomVersionId, serde::base64::Base64};
/// # use ruma_signatures::{hash_and_sign_event, Ed25519KeyPair};
/// #
/// const PKCS8: &str = "\
/// MFECAQEwBQYDK2VwBCIEINjozvdfbsGEt6DD+7Uf4PiJ/YvTNXV2mIPc/\
/// tA0T+6tgSEA3TPraTczVkDPTRaX4K+AfUuyx7Mzq1UafTXypnl0t2k\
/// ";
///
/// let document: Base64 = Base64::parse(PKCS8).unwrap();
///
/// // Create an Ed25519 key pair.
/// let key_pair = Ed25519KeyPair::from_der(
/// document.as_bytes(),
/// "1".into(), // The "version" of the key.
/// )
/// .unwrap();
///
/// // Deserialize an event from JSON.
/// let mut object = serde_json::from_str(
/// r#"{
/// "room_id": "!x:domain",
/// "sender": "@a:domain",
/// "origin": "domain",
/// "origin_server_ts": 1000000,
/// "signatures": {},
/// "hashes": {},
/// "type": "X",
/// "content": {},
/// "prev_events": [],
/// "auth_events": [],
/// "depth": 3,
/// "unsigned": {
/// "age_ts": 1000000
/// }
/// }"#,
/// )
/// .unwrap();
///
/// // Hash and sign the JSON with the key pair.
/// assert!(hash_and_sign_event("domain", &key_pair, &mut object, &RoomVersionId::V1).is_ok());
/// ```
///
/// This will modify the JSON from the structure shown to a structure like this:
///
/// ```json
/// {
/// "auth_events": [],
/// "content": {},
/// "depth": 3,
/// "hashes": {
/// "sha256": "5jM4wQpv6lnBo7CLIghJuHdW+s2CMBJPUOGOC89ncos"
/// },
/// "origin": "domain",
/// "origin_server_ts": 1000000,
/// "prev_events": [],
/// "room_id": "!x:domain",
/// "sender": "@a:domain",
/// "signatures": {
/// "domain": {
/// "ed25519:1": "KxwGjPSDEtvnFgU00fwFz+l6d2pJM6XBIaMEn81SXPTRl16AqLAYqfIReFGZlHi5KLjAWbOoMszkwsQma+lYAg"
/// }
/// },
/// "type": "X",
/// "unsigned": {
/// "age_ts": 1000000
/// }
/// }
/// ```
///
/// Notice the addition of `hashes` and `signatures`.
pub fn hash_and_sign_event<K>(
entity_id: &str,
key_pair: &K,
object: &mut CanonicalJsonObject,
version: &RoomVersionId,
) -> Result<(), Error>
where
K: KeyPair,
{
let hash = content_hash(object)?;
let hashes_value = object
.entry("hashes".to_owned())
.or_insert_with(|| CanonicalJsonValue::Object(BTreeMap::new()));
match hashes_value {
CanonicalJsonValue::Object(hashes) => {
hashes.insert("sha256".into(), CanonicalJsonValue::String(hash.encode()))
}
_ => return Err(JsonError::not_of_type("hashes", JsonType::Object)),
};
let mut redacted = redact(object.clone(), version, None)?;
sign_json(entity_id, key_pair, &mut redacted)?;
object.insert("signatures".into(), mem::take(redacted.get_mut("signatures").unwrap()));
Ok(())
}
/// Verifies that the signed event contains all the required valid signatures.
///
/// Some room versions may require signatures from multiple homeservers, so this function takes a
/// map from servers to sets of public keys. Signatures are verified for each required homeserver.
/// All known public keys for a homeserver should be provided. The first one found on the given
/// event will be used.
///
/// If the `Ok` variant is returned by this function, it will contain a `Verified` value which
/// distinguishes an event with valid signatures and a matching content hash with an event with
/// only valid signatures. See the documentation for `Verified` for details.
///
/// # Parameters
///
/// * public_key_map: A map from entity identifiers to a map from key identifiers to public keys.
/// Generally, entity identifiers are server names—the host/IP/port of a homeserver (e.g.
/// "example.com") for which a signature must be verified. Key identifiers for each server (e.g.
/// "ed25519:1") then map to their respective public keys.
/// * object: The JSON object of the event that was signed.
/// * version: Room version of the given event
///
/// # Examples
///
/// ```rust
/// # use std::collections::BTreeMap;
/// # use ruma_common::RoomVersionId;
/// # use ruma_common::serde::Base64;
/// # use ruma_signatures::{verify_event, Verified};
/// #
/// const PUBLIC_KEY: &[u8] = b"XGX0JRS2Af3be3knz2fBiRbApjm2Dh61gXDJA8kcJNI";
///
/// // Deserialize an event from JSON.
/// let object = serde_json::from_str(
/// r#"{
/// "auth_events": [],
/// "content": {},
/// "depth": 3,
/// "hashes": {
/// "sha256": "5jM4wQpv6lnBo7CLIghJuHdW+s2CMBJPUOGOC89ncos"
/// },
/// "origin": "domain",
/// "origin_server_ts": 1000000,
/// "prev_events": [],
/// "room_id": "!x:domain",
/// "sender": "@a:domain",
/// "signatures": {
/// "domain": {
/// "ed25519:1": "KxwGjPSDEtvnFgU00fwFz+l6d2pJM6XBIaMEn81SXPTRl16AqLAYqfIReFGZlHi5KLjAWbOoMszkwsQma+lYAg"
/// }
/// },
/// "type": "X",
/// "unsigned": {
/// "age_ts": 1000000
/// }
/// }"#
/// ).unwrap();
///
/// // Create the `PublicKeyMap` that will inform `verify_json` which signatures to verify.
/// let mut public_key_set = BTreeMap::new();
/// public_key_set.insert("ed25519:1".into(), Base64::parse(PUBLIC_KEY.to_owned()).unwrap());
/// let mut public_key_map = BTreeMap::new();
/// public_key_map.insert("domain".into(), public_key_set);
///
/// // Verify at least one signature for each entity in `public_key_map`.
/// let verification_result = verify_event(&public_key_map, &object, &RoomVersionId::V6);
/// assert!(verification_result.is_ok());
/// assert_eq!(verification_result.unwrap(), Verified::All);
/// ```
pub fn verify_event(
public_key_map: &PublicKeyMap,
object: &CanonicalJsonObject,
version: &RoomVersionId,
) -> Result<Verified, Error> {
let redacted = redact(object.clone(), version, None)?;
let hash = match object.get("hashes") {
Some(hashes_value) => match hashes_value {
CanonicalJsonValue::Object(hashes) => match hashes.get("sha256") {
Some(hash_value) => match hash_value {
CanonicalJsonValue::String(hash) => hash,
_ => return Err(JsonError::not_of_type("sha256 hash", JsonType::String)),
},
None => return Err(JsonError::not_of_type("hashes", JsonType::Object)),
},
_ => return Err(JsonError::field_missing_from_object("sha256")),
},
None => return Err(JsonError::field_missing_from_object("hashes")),
};
let signature_map = match object.get("signatures") {
Some(CanonicalJsonValue::Object(signatures)) => signatures,
Some(_) => return Err(JsonError::not_of_type("signatures", JsonType::Object)),
None => return Err(JsonError::field_missing_from_object("signatures")),
};
let servers_to_check = servers_to_check_signatures(object, version)?;
let canonical_json = from_json_str(&canonical_json(&redacted)?).map_err(JsonError::from)?;
for entity_id in servers_to_check {
let signature_set = match signature_map.get(entity_id.as_str()) {
Some(CanonicalJsonValue::Object(set)) => set,
Some(_) => {
return Err(JsonError::not_multiples_of_type("signature sets", JsonType::Object))
}
None => return Err(VerificationError::signature_not_found(entity_id)),
};
let public_keys = public_key_map
.get(entity_id.as_str())
.ok_or_else(|| VerificationError::public_key_not_found(entity_id))?;
let mut checked = false;
for (key_id, signature) in signature_set {
// Since only ed25519 is supported right now, we don't actually need to check what the
// algorithm is. If it split successfully, it's ed25519.
if split_id(key_id).is_err() {
continue;
}
let public_key = match public_keys.get(key_id) {
Some(public_key) => public_key,
None => return Err(VerificationError::UnknownPublicKeysForSignature.into()),
};
let signature = match signature {
CanonicalJsonValue::String(signature) => signature,
_ => return Err(JsonError::not_of_type("signature", JsonType::String)),
};
let signature = Base64::<Standard>::parse(signature)
.map_err(|e| ParseError::base64("signature", signature, e))?;
verify_json_with(
&Ed25519Verifier,
public_key.as_bytes(),
signature.as_bytes(),
&canonical_json,
)?;
checked = true;
}
if !checked {
return Err(VerificationError::UnknownPublicKeysForSignature.into());
}
}
let calculated_hash = content_hash(object)?;
if let Ok(hash) = Base64::<Standard>::parse(hash) {
if hash.as_bytes() == calculated_hash.as_bytes() {
return Ok(Verified::All);
}
}
Ok(Verified::Signatures)
}
/// Internal implementation detail of the canonical JSON algorithm.
///
/// Allows customization of the fields that will be removed before serializing.
fn canonical_json_with_fields_to_remove(
object: &CanonicalJsonObject,
fields: &[&str],
) -> Result<String, Error> {
let mut owned_object = object.clone();
for field in fields {
owned_object.remove(*field);
}
to_json_string(&owned_object).map_err(|e| Error::Json(e.into()))
}
/// Extracts the server names to check signatures for given event.
///
/// It will return the sender's server (unless it's a third party invite) and the event id server
/// (on v1 and v2 room versions)
///
/// Starting with room version 8, if join_authorised_via_users_server is present, a signature from
/// that user is required.
fn servers_to_check_signatures(
object: &CanonicalJsonObject,
version: &RoomVersionId,
) -> Result<BTreeSet<OwnedServerName>, Error> {
let mut servers_to_check = BTreeSet::new();
if !is_third_party_invite(object)? {
match object.get("sender") {
Some(CanonicalJsonValue::String(raw_sender)) => {
let user_id = <&UserId>::try_from(raw_sender.as_str())
.map_err(|e| Error::from(ParseError::UserId(e)))?;
servers_to_check.insert(user_id.server_name().to_owned());
}
_ => return Err(JsonError::not_of_type("sender", JsonType::String)),
};
}
match version {
RoomVersionId::V1 | RoomVersionId::V2 => match object.get("event_id") {
Some(CanonicalJsonValue::String(raw_event_id)) => {
let event_id: OwnedEventId =
raw_event_id.parse().map_err(|e| Error::from(ParseError::EventId(e)))?;
let server_name = event_id
.server_name()
.ok_or_else(|| ParseError::from_event_id_by_room_version(&event_id, version))?
.to_owned();
servers_to_check.insert(server_name);
}
_ => {
return Err(JsonError::field_missing_from_object("event_id"));
}
},
RoomVersionId::V3
| RoomVersionId::V4
| RoomVersionId::V5
| RoomVersionId::V6
| RoomVersionId::V7 => {}
// TODO: And for all future versions that have join_authorised_via_users_server
RoomVersionId::V8 | RoomVersionId::V9 | RoomVersionId::V10 | RoomVersionId::V11 => {
if let Some(authorized_user) = object
.get("content")
.and_then(|c| c.as_object())
.and_then(|c| c.get("join_authorised_via_users_server"))
{
let authorized_user = authorized_user.as_str().ok_or_else(|| {
JsonError::not_of_type("join_authorised_via_users_server", JsonType::String)
})?;
let authorized_user = <&UserId>::try_from(authorized_user)
.map_err(|e| Error::from(ParseError::UserId(e)))?;
servers_to_check.insert(authorized_user.server_name().to_owned());
}
}
_ => unimplemented!(),
}
Ok(servers_to_check)
}
/// Checks if `object` contains an event of type `m.room.third_party_invite`
fn is_third_party_invite(object: &CanonicalJsonObject) -> Result<bool, Error> {
match object.get("type") {
Some(CanonicalJsonValue::String(raw_type)) => Ok(raw_type == "m.room.third_party_invite"),
_ => Err(JsonError::not_of_type("type", JsonType::String)),
}
}
#[cfg(test)]
mod tests {
use std::collections::BTreeMap;
use assert_matches2::assert_matches;
use ruma_common::{
serde::Base64, CanonicalJsonValue, RoomVersionId, ServerSigningKeyId, SigningKeyAlgorithm,
};
use serde_json::json;
use super::canonical_json;
use crate::{
sign_json, verify_event, Ed25519KeyPair, Error, PublicKeyMap, PublicKeySet,
VerificationError, Verified,
};
#[test]
fn canonical_json_complex() {
let data = json!({
"auth": {
"success": true,
"mxid": "@john.doe:example.com",
"profile": {
"display_name": "John Doe",
"three_pids": [
{
"medium": "email",
"address": "john.doe@example.org"
},
{
"medium": "msisdn",
"address": "123456789"
}
]
}
}
});
let canonical = r#"{"auth":{"mxid":"@john.doe:example.com","profile":{"display_name":"John Doe","three_pids":[{"address":"john.doe@example.org","medium":"email"},{"address":"123456789","medium":"msisdn"}]},"success":true}}"#;
let object = match CanonicalJsonValue::try_from(data).unwrap() {
CanonicalJsonValue::Object(obj) => obj,
_ => unreachable!(),
};
assert_eq!(canonical_json(&object).unwrap(), canonical);
}
#[test]
fn verify_event_does_not_check_signatures_for_third_party_invites() {
let signed_event = serde_json::from_str(
r#"{
"auth_events": [],
"content": {},
"depth": 3,
"hashes": {
"sha256": "5jM4wQpv6lnBo7CLIghJuHdW+s2CMBJPUOGOC89ncos"
},
"origin": "domain",
"origin_server_ts": 1000000,
"prev_events": [],
"room_id": "!x:domain",
"sender": "@a:domain",
"signatures": {
"domain": {
"ed25519:1": "KxwGjPSDEtvnFgU00fwFz+l6d2pJM6XBIaMEn81SXPTRl16AqLAYqfIReFGZlHi5KLjAWbOoMszkwsQma+lYAg"
}
},
"type": "m.room.third_party_invite",
"unsigned": {
"age_ts": 1000000
}
}"#
).unwrap();
let public_key_map = BTreeMap::new();
let verification =
verify_event(&public_key_map, &signed_event, &RoomVersionId::V6).unwrap();
assert_eq!(verification, Verified::Signatures);
}
#[test]
fn verify_event_check_signatures_for_both_sender_and_event_id() {
let key_pair_sender = generate_key_pair("1");
let key_pair_event = generate_key_pair("2");
let mut signed_event = serde_json::from_str(
r#"{
"event_id": "$event_id:domain-event",
"auth_events": [],
"content": {},
"depth": 3,
"hashes": {
"sha256": "5jM4wQpv6lnBo7CLIghJuHdW+s2CMBJPUOGOC89ncos"
},
"origin": "domain",
"origin_server_ts": 1000000,
"prev_events": [],
"room_id": "!x:domain",
"sender": "@name:domain-sender",
"type": "X",
"unsigned": {
"age_ts": 1000000
}
}"#,
)
.unwrap();
sign_json("domain-sender", &key_pair_sender, &mut signed_event).unwrap();
sign_json("domain-event", &key_pair_event, &mut signed_event).unwrap();
let mut public_key_map = BTreeMap::new();
add_key_to_map(&mut public_key_map, "domain-sender", &key_pair_sender);
add_key_to_map(&mut public_key_map, "domain-event", &key_pair_event);
let verification =
verify_event(&public_key_map, &signed_event, &RoomVersionId::V1).unwrap();
assert_eq!(verification, Verified::Signatures);
}
#[test]
fn verify_event_check_signatures_for_authorized_user() {
let key_pair_sender = generate_key_pair("1");
let key_pair_authorized = generate_key_pair("2");
let mut signed_event = serde_json::from_str(
r#"{
"event_id": "$event_id:domain-event",
"auth_events": [],
"content": {"join_authorised_via_users_server": "@authorized:domain-authorized"},
"depth": 3,
"hashes": {
"sha256": "5jM4wQpv6lnBo7CLIghJuHdW+s2CMBJPUOGOC89ncos"
},
"origin": "domain",
"origin_server_ts": 1000000,
"prev_events": [],
"room_id": "!x:domain",
"sender": "@name:domain-sender",
"type": "m.room.member",
"unsigned": {
"age_ts": 1000000
}
}"#,
)
.unwrap();
sign_json("domain-sender", &key_pair_sender, &mut signed_event).unwrap();
sign_json("domain-authorized", &key_pair_authorized, &mut signed_event).unwrap();
let mut public_key_map = BTreeMap::new();
add_key_to_map(&mut public_key_map, "domain-sender", &key_pair_sender);
add_key_to_map(&mut public_key_map, "domain-authorized", &key_pair_authorized);
let verification =
verify_event(&public_key_map, &signed_event, &RoomVersionId::V9).unwrap();
assert_eq!(verification, Verified::Signatures);
}
#[test]
fn verification_fails_if_missing_signatures_for_authorized_user() {
let key_pair_sender = generate_key_pair("1");
let mut signed_event = serde_json::from_str(
r#"{
"event_id": "$event_id:domain-event",
"auth_events": [],
"content": {"join_authorised_via_users_server": "@authorized:domain-authorized"},
"depth": 3,
"hashes": {
"sha256": "5jM4wQpv6lnBo7CLIghJuHdW+s2CMBJPUOGOC89ncos"
},
"origin": "domain",
"origin_server_ts": 1000000,
"prev_events": [],
"room_id": "!x:domain",
"sender": "@name:domain-sender",
"type": "X",
"unsigned": {
"age_ts": 1000000
}
}"#,
)
.unwrap();
sign_json("domain-sender", &key_pair_sender, &mut signed_event).unwrap();
let mut public_key_map = BTreeMap::new();
add_key_to_map(&mut public_key_map, "domain-sender", &key_pair_sender);
let verification_result = verify_event(&public_key_map, &signed_event, &RoomVersionId::V9);
assert_matches!(
verification_result,
Err(Error::Verification(VerificationError::SignatureNotFound(server)))
);
assert_eq!(server, "domain-authorized");
}
#[test]
fn verification_fails_if_required_keys_are_not_given() {
let key_pair_sender = generate_key_pair("1");
let mut signed_event = serde_json::from_str(
r#"{
"auth_events": [],
"content": {},
"depth": 3,
"hashes": {
"sha256": "5jM4wQpv6lnBo7CLIghJuHdW+s2CMBJPUOGOC89ncos"
},
"origin": "domain",
"origin_server_ts": 1000000,
"prev_events": [],
"room_id": "!x:domain",
"sender": "@name:domain-sender",
"type": "X",
"unsigned": {
"age_ts": 1000000
}
}"#,
)
.unwrap();
sign_json("domain-sender", &key_pair_sender, &mut signed_event).unwrap();
// Verify with an empty public key map should fail due to missing public keys
let public_key_map = BTreeMap::new();
let verification_result = verify_event(&public_key_map, &signed_event, &RoomVersionId::V6);
assert_matches!(
verification_result,
Err(Error::Verification(VerificationError::PublicKeyNotFound(entity)))
);
assert_eq!(entity, "domain-sender");
}
#[test]
fn verify_event_fails_if_public_key_is_invalid() {
let key_pair_sender = generate_key_pair("1");
let mut signed_event = serde_json::from_str(
r#"{
"auth_events": [],
"content": {},
"depth": 3,
"hashes": {
"sha256": "5jM4wQpv6lnBo7CLIghJuHdW+s2CMBJPUOGOC89ncos"
},
"origin": "domain",
"origin_server_ts": 1000000,
"prev_events": [],
"room_id": "!x:domain",
"sender": "@name:domain-sender",
"type": "X",
"unsigned": {
"age_ts": 1000000
}
}"#,
)
.unwrap();
sign_json("domain-sender", &key_pair_sender, &mut signed_event).unwrap();
let mut public_key_map = PublicKeyMap::new();
let mut sender_key_map = PublicKeySet::new();
let newly_generated_key_pair = generate_key_pair("2");
let encoded_public_key = Base64::new(newly_generated_key_pair.public_key().to_vec());
let version = ServerSigningKeyId::from_parts(
SigningKeyAlgorithm::Ed25519,
key_pair_sender.version().into(),
);
sender_key_map.insert(version.to_string(), encoded_public_key);
public_key_map.insert("domain-sender".to_owned(), sender_key_map);
let verification_result = verify_event(&public_key_map, &signed_event, &RoomVersionId::V6);
assert_matches!(
verification_result,
Err(Error::Verification(VerificationError::Signature(error)))
);
// dalek doesn't expose InternalError :(
// https://github.com/dalek-cryptography/ed25519-dalek/issues/174
assert!(format!("{error:?}").contains("Some(Verification equation was not satisfied)"));
}
#[test]
fn verify_event_check_signatures_for_sender_is_allowed_with_unknown_algorithms_in_key_map() {
let key_pair_sender = generate_key_pair("1");
let mut signed_event = serde_json::from_str(
r#"{
"auth_events": [],
"content": {},
"depth": 3,
"hashes": {
"sha256": "5jM4wQpv6lnBo7CLIghJuHdW+s2CMBJPUOGOC89ncos"
},
"origin": "domain",
"origin_server_ts": 1000000,
"prev_events": [],
"room_id": "!x:domain",
"sender": "@name:domain-sender",
"type": "X",
"unsigned": {
"age_ts": 1000000
}
}"#,
)
.unwrap();
sign_json("domain-sender", &key_pair_sender, &mut signed_event).unwrap();
let mut public_key_map = BTreeMap::new();
add_key_to_map(&mut public_key_map, "domain-sender", &key_pair_sender);
add_invalid_key_to_map(&mut public_key_map, "domain-sender", &generate_key_pair("2"));
let verification =
verify_event(&public_key_map, &signed_event, &RoomVersionId::V6).unwrap();
assert_eq!(verification, Verified::Signatures);
}
#[test]
fn verify_event_fails_with_missing_key_when_event_is_signed_multiple_times_by_same_entity() {
let key_pair_sender = generate_key_pair("1");
let secondary_key_pair_sender = generate_key_pair("2");
let mut signed_event = serde_json::from_str(
r#"{
"auth_events": [],
"content": {},
"depth": 3,
"hashes": {
"sha256": "5jM4wQpv6lnBo7CLIghJuHdW+s2CMBJPUOGOC89ncos"
},
"origin": "domain",
"origin_server_ts": 1000000,
"prev_events": [],
"room_id": "!x:domain",
"sender": "@name:domain-sender",
"type": "X",
"unsigned": {
"age_ts": 1000000
}
}"#,
)
.unwrap();
sign_json("domain-sender", &key_pair_sender, &mut signed_event).unwrap();
sign_json("domain-sender", &secondary_key_pair_sender, &mut signed_event).unwrap();
let mut public_key_map = BTreeMap::new();
add_key_to_map(&mut public_key_map, "domain-sender", &key_pair_sender);
let verification_result = verify_event(&public_key_map, &signed_event, &RoomVersionId::V6);
assert_matches!(
verification_result,
Err(Error::Verification(VerificationError::UnknownPublicKeysForSignature))
);
}
#[test]
fn verify_event_checks_all_signatures_from_sender_entity() {
let key_pair_sender = generate_key_pair("1");
let secondary_key_pair_sender = generate_key_pair("2");
let mut signed_event = serde_json::from_str(
r#"{
"auth_events": [],
"content": {},
"depth": 3,
"hashes": {
"sha256": "5jM4wQpv6lnBo7CLIghJuHdW+s2CMBJPUOGOC89ncos"
},
"origin": "domain",
"origin_server_ts": 1000000,
"prev_events": [],
"room_id": "!x:domain",
"sender": "@name:domain-sender",
"type": "X",
"unsigned": {
"age_ts": 1000000
}
}"#,
)
.unwrap();
sign_json("domain-sender", &key_pair_sender, &mut signed_event).unwrap();
sign_json("domain-sender", &secondary_key_pair_sender, &mut signed_event).unwrap();
let mut public_key_map = BTreeMap::new();
add_key_to_map(&mut public_key_map, "domain-sender", &key_pair_sender);
add_key_to_map(&mut public_key_map, "domain-sender", &secondary_key_pair_sender);
let verification =
verify_event(&public_key_map, &signed_event, &RoomVersionId::V6).unwrap();
assert_eq!(verification, Verified::Signatures);
}
#[test]
fn verify_event_with_single_key_with_unknown_algorithm_should_not_accept_event() {
let key_pair_sender = generate_key_pair("1");
let signed_event = serde_json::from_str(
r#"{
"auth_events": [],
"content": {},
"depth": 3,
"hashes": {
"sha256": "5jM4wQpv6lnBo7CLIghJuHdW+s2CMBJPUOGOC89ncos"
},
"origin": "domain",
"origin_server_ts": 1000000,
"prev_events": [],
"room_id": "!x:domain",
"sender": "@name:domain-sender",
"type": "X",
"unsigned": {
"age_ts": 1000000
},
"signatures": {
"domain-sender": {
"an-unknown-algorithm:1": "pE5UT/4JiY7YZDtZDOsEaxc0wblurdoYqNQx4bCXORA3vLFOGOK10Q/xXVLPWWgIKo15LNvWwWd/2YjmdPvYCg"
}
}
}"#,
)
.unwrap();
let mut public_key_map = BTreeMap::new();
add_invalid_key_to_map(&mut public_key_map, "domain-sender", &key_pair_sender);
let verification_result = verify_event(&public_key_map, &signed_event, &RoomVersionId::V6);
assert_matches!(
verification_result,
Err(Error::Verification(VerificationError::UnknownPublicKeysForSignature))
);
}
fn generate_key_pair(name: &str) -> Ed25519KeyPair {
let key_content = Ed25519KeyPair::generate().unwrap();
Ed25519KeyPair::from_der(&key_content, name.to_owned())
.unwrap_or_else(|_| panic!("{:?}", &key_content))
}
fn add_key_to_map(public_key_map: &mut PublicKeyMap, name: &str, pair: &Ed25519KeyPair) {
let sender_key_map = public_key_map.entry(name.to_owned()).or_default();
let encoded_public_key = Base64::new(pair.public_key().to_vec());
let version =
ServerSigningKeyId::from_parts(SigningKeyAlgorithm::Ed25519, pair.version().into());
sender_key_map.insert(version.to_string(), encoded_public_key);
}
fn add_invalid_key_to_map(
public_key_map: &mut PublicKeyMap,
name: &str,
pair: &Ed25519KeyPair,
) {
let sender_key_map = public_key_map.entry(name.to_owned()).or_default();
let encoded_public_key = Base64::new(pair.public_key().to_vec());
let version = ServerSigningKeyId::from_parts(
SigningKeyAlgorithm::from("an-unknown-algorithm"),
pair.version().into(),
);
sender_key_map.insert(version.to_string(), encoded_public_key);
}
}