signatures: Handle room version 5 / 6 differences

ruma-signatures/Cargo.toml

@@ -15,5 +15,6 @@ version = "0.6.0-dev.1"
 [dependencies]
 base64 = "0.12.3"
 ring = "0.16.15"
+ruma-identifiers = { version = "0.17.4", path = "../ruma-identifiers" }
 serde_json = "1.0.57"
 untrusted = "0.7.1"

ruma-signatures/src/functions.rs

@@ -4,6 +4,7 @@ use std::{cmp, collections::HashMap, mem};
 
 use base64::{decode_config, encode_config, STANDARD_NO_PAD};
 use ring::digest::{digest, SHA256};
+use ruma_identifiers::RoomVersionId;
 use serde_json::{from_str, from_value, map::Map, to_string, to_value, Value};
 
 use crate::{
@@ -33,7 +34,7 @@ static ALLOWED_KEYS: &[&str] = &[
     "membership",
 ];
 
-fn allowed_content_keys_for(event_type: &str) -> &'static [&'static str] {
+fn allowed_content_keys_for(event_type: &str, version: &RoomVersionId) -> &'static [&'static str] {
     match event_type {
         "m.room.member" => &["membership"],
         "m.room.create" => &["creator"],
@@ -48,6 +49,16 @@ fn allowed_content_keys_for(event_type: &str) -> &'static [&'static str] {
             "users",
             "users_default",
         ],
+        "m.room.aliases" => match version {
+            RoomVersionId::Version1
+            | RoomVersionId::Version2
+            | RoomVersionId::Version3
+            | RoomVersionId::Version4
+            | RoomVersionId::Version5 => &["join_rule"],
+            // All other room versions, including custom ones, are treated by version 6 rules.
+            // TODO: Should we return an error for unknown versions instead?
+            _ => &[],
+        },
         "m.room.history_visibility" => &["history_visibility"],
         _ => &[],
     }
@@ -366,8 +377,8 @@ pub fn content_hash(value: &Value) -> Result<String, Error> {
 /// # Errors
 ///
 /// Returns an error if the provided JSON value is not a JSON object.
-pub fn reference_hash(value: &Value) -> Result<String, Error> {
-    let redacted_value = redact(value)?;
+pub fn reference_hash(value: &Value, version: &RoomVersionId) -> Result<String, Error> {
+    let redacted_value = redact(value, version)?;
 
     let json =
         canonical_json_with_fields_to_remove(&redacted_value, REFERENCE_HASH_FIELDS_TO_REMOVE)?;
@@ -403,6 +414,9 @@ pub fn reference_hash(value: &Value) -> Result<String, Error> {
 /// # Examples
 ///
 /// ```rust
+/// # use ruma_identifiers::RoomVersionId;
+/// # use ruma_signatures::{hash_and_sign_event, Ed25519KeyPair};
+/// #
 /// const PKCS8: &str = "\
 ///     MFMCAQEwBQYDK2VwBCIEINjozvdfbsGEt6DD+7Uf4PiJ/YvTNXV2mIPc/\
 ///     tA0T+6toSMDIQDdM+tpNzNWQM9NFpfgr4B9S7LHszOrVRp9NfKmeXS3aQ\
@@ -411,7 +425,7 @@ pub fn reference_hash(value: &Value) -> Result<String, Error> {
 /// let document = base64::decode_config(&PKCS8, base64::STANDARD_NO_PAD).unwrap();
 ///
 /// // Create an Ed25519 key pair.
-/// let key_pair = ruma_signatures::Ed25519KeyPair::new(
+/// let key_pair = Ed25519KeyPair::new(
 ///     &document,
 ///     "1".into(), // The "version" of the key.
 /// ).unwrap();
@@ -437,7 +451,7 @@ pub fn reference_hash(value: &Value) -> Result<String, Error> {
 /// ).unwrap();
 ///
 /// // Hash and sign the JSON with the key pair.
-/// assert!(ruma_signatures::hash_and_sign_event("domain", &key_pair, &mut value).is_ok());
+/// assert!(hash_and_sign_event("domain", &key_pair, &mut value, &RoomVersionId::Version1).is_ok());
 /// ```
 ///
 /// This will modify the JSON from the structure shown to a structure like this:
@@ -468,7 +482,12 @@ pub fn reference_hash(value: &Value) -> Result<String, Error> {
 /// ```
 ///
 /// Notice the addition of `hashes` and `signatures`.
-pub fn hash_and_sign_event<K>(entity_id: &str, key_pair: &K, value: &mut Value) -> Result<(), Error>
+pub fn hash_and_sign_event<K>(
+    entity_id: &str,
+    key_pair: &K,
+    value: &mut Value,
+    version: &RoomVersionId,
+) -> Result<(), Error>
 where
     K: KeyPair,
 {
@@ -490,7 +509,7 @@ where
         };
     }
 
-    let mut redacted = redact(value)?;
+    let mut redacted = redact(value, version)?;
 
     sign_json(entity_id, key_pair, &mut redacted)?;
 
@@ -524,8 +543,10 @@ where
 /// # Examples
 ///
 /// ```rust
-/// use std::collections::HashMap;
-///
+/// # use std::collections::HashMap;
+/// # use ruma_identifiers::RoomVersionId;
+/// # use ruma_signatures::verify_event;
+/// #
 /// const PUBLIC_KEY: &str = "XGX0JRS2Af3be3knz2fBiRbApjm2Dh61gXDJA8kcJNI";
 ///
 /// // Deserialize an event from JSON.
@@ -561,10 +582,14 @@ where
 /// 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_event(&public_key_map, &value).is_ok());
+/// assert!(verify_event(&public_key_map, &value, &RoomVersionId::Version6).is_ok());
 /// ```
-pub fn verify_event(public_key_map: &PublicKeyMap, value: &Value) -> Result<Verified, Error> {
-    let redacted = redact(value)?;
+pub fn verify_event(
+    public_key_map: &PublicKeyMap,
+    value: &Value,
+    version: &RoomVersionId,
+) -> Result<Verified, Error> {
+    let redacted = redact(value, version)?;
 
     let map = match redacted {
         Value::Object(ref map) => map,
@@ -694,7 +719,7 @@ fn canonical_json_with_fields_to_remove(value: &Value, fields: &[&str]) -> Resul
 /// * `value` contains a field called `hashes` that is not a JSON object.
 /// * `value` contains a field called `signatures` that is not a JSON object.
 /// * `value` is missing the `type` field or the field is not a JSON string.
-pub fn redact(value: &Value) -> Result<Value, Error> {
+pub fn redact(value: &Value, version: &RoomVersionId) -> Result<Value, Error> {
     if !value.is_object() {
         return Err(Error::new("JSON value must be a JSON object"));
     }
@@ -709,7 +734,7 @@ pub fn redact(value: &Value) -> Result<Value, Error> {
     };
 
     let allowed_content_keys = match event_type_value.as_str() {
-        Some(event_type) => allowed_content_keys_for(event_type),
+        Some(event_type) => allowed_content_keys_for(event_type, version),
         None => return Err(Error::new("field `type` in JSON value must be a JSON string")),
     };
 

ruma-signatures/src/lib.rs

@@ -176,6 +176,7 @@ mod test {
 
     use base64::{decode_config, STANDARD_NO_PAD};
     use ring::signature::{Ed25519KeyPair as RingEd25519KeyPair, KeyPair as _};
+    use ruma_identifiers::RoomVersionId;
     use serde_json::{from_str, json, to_string, to_value, Value};
 
     use super::{
@@ -422,7 +423,7 @@ mod test {
         }"#;
 
         let mut value = from_str::<Value>(json).unwrap();
-        hash_and_sign_event("domain", &key_pair, &mut value).unwrap();
+        hash_and_sign_event("domain", &key_pair, &mut value, &RoomVersionId::Version5).unwrap();
 
         assert_eq!(
             to_string(&value).unwrap(),
@@ -455,7 +456,7 @@ mod test {
         }"#;
 
         let mut value = from_str::<Value>(json).unwrap();
-        hash_and_sign_event("domain", &key_pair, &mut value).unwrap();
+        hash_and_sign_event("domain", &key_pair, &mut value, &RoomVersionId::Version5).unwrap();
 
         assert_eq!(
             to_string(&value).unwrap(),
@@ -496,6 +497,6 @@ mod test {
             }"#
         ).unwrap();
 
-        assert!(verify_event(&public_key_map, &value).is_ok());
+        assert!(verify_event(&public_key_map, &value, &RoomVersionId::Version5).is_ok());
     }
 }