2022-05-27 12:04:23 +02:00

1284 lines
46 KiB
Rust

use std::{borrow::Borrow, collections::BTreeSet};
use js_int::{int, Int};
use ruma_common::{
events::{
room::{
create::RoomCreateEventContent,
join_rules::{JoinRule, RoomJoinRulesEventContent},
member::{MembershipState, ThirdPartyInvite},
power_levels::RoomPowerLevelsEventContent,
third_party_invite::RoomThirdPartyInviteEventContent,
},
RoomEventType, StateEventType,
},
serde::{Base64, Raw},
OwnedUserId, RoomVersionId, UserId,
};
use serde::{de::IgnoredAny, Deserialize};
use serde_json::{from_str as from_json_str, value::RawValue as RawJsonValue};
use tracing::{debug, error, info, warn};
use crate::{room_version::RoomVersion, Error, Event, PowerLevelsContentFields, Result};
// FIXME: field extracting could be bundled for `content`
#[derive(Deserialize)]
struct GetMembership {
membership: MembershipState,
}
#[derive(Deserialize)]
struct RoomMemberContentFields {
membership: Option<Raw<MembershipState>>,
join_authorised_via_users_server: Option<Raw<OwnedUserId>>,
}
#[derive(Deserialize)]
struct PowerLevelsContentInvite {
invite: Int,
}
/// For the given event `kind` what are the relevant auth events that are needed to authenticate
/// this `content`.
///
/// # Errors
///
/// This function will return an error if the supplied `content` is not a JSON object.
pub fn auth_types_for_event(
kind: &RoomEventType,
sender: &UserId,
state_key: Option<&str>,
content: &RawJsonValue,
) -> serde_json::Result<Vec<(StateEventType, String)>> {
if kind == &RoomEventType::RoomCreate {
return Ok(vec![]);
}
let mut auth_types = vec![
(StateEventType::RoomPowerLevels, "".to_owned()),
(StateEventType::RoomMember, sender.to_string()),
(StateEventType::RoomCreate, "".to_owned()),
];
if kind == &RoomEventType::RoomMember {
#[derive(Deserialize)]
struct RoomMemberContentFields {
membership: Option<Raw<MembershipState>>,
third_party_invite: Option<Raw<ThirdPartyInvite>>,
join_authorised_via_users_server: Option<Raw<OwnedUserId>>,
}
if let Some(state_key) = state_key {
let content: RoomMemberContentFields = from_json_str(content.get())?;
if let Some(Ok(membership)) = content.membership.map(|m| m.deserialize()) {
if [MembershipState::Join, MembershipState::Invite, MembershipState::Knock]
.contains(&membership)
{
let key = (StateEventType::RoomJoinRules, "".to_owned());
if !auth_types.contains(&key) {
auth_types.push(key);
}
if let Some(Ok(u)) =
content.join_authorised_via_users_server.map(|m| m.deserialize())
{
let key = (StateEventType::RoomMember, u.to_string());
if !auth_types.contains(&key) {
auth_types.push(key);
}
}
}
let key = (StateEventType::RoomMember, state_key.to_owned());
if !auth_types.contains(&key) {
auth_types.push(key);
}
if membership == MembershipState::Invite {
if let Some(Ok(t_id)) = content.third_party_invite.map(|t| t.deserialize()) {
let key = (StateEventType::RoomThirdPartyInvite, t_id.signed.token);
if !auth_types.contains(&key) {
auth_types.push(key);
}
}
}
}
}
}
Ok(auth_types)
}
/// Authenticate the incoming `event`.
///
/// The steps of authentication are:
///
/// * check that the event is being authenticated for the correct room
/// * then there are checks for specific event types
///
/// The `fetch_state` closure should gather state from a state snapshot. We need to know if the
/// event passes auth against some state not a recursive collection of auth_events fields.
pub fn auth_check<E: Event>(
room_version: &RoomVersion,
incoming_event: impl Event,
current_third_party_invite: Option<impl Event>,
fetch_state: impl Fn(&StateEventType, &str) -> Option<E>,
) -> Result<bool> {
info!(
"auth_check beginning for {} ({})",
incoming_event.event_id(),
incoming_event.event_type()
);
// [synapse] check that all the events are in the same room as `incoming_event`
// [synapse] do_sig_check check the event has valid signatures for member events
// TODO do_size_check is false when called by `iterative_auth_check`
// do_size_check is also mostly accomplished by ruma with the exception of checking event_type,
// state_key, and json are below a certain size (255 and 65_536 respectively)
let sender = incoming_event.sender();
// Implementation of https://spec.matrix.org/v1.2/rooms/v1/#authorization-rules
//
// 1. If type is m.room.create:
if *incoming_event.event_type() == RoomEventType::RoomCreate {
#[derive(Deserialize)]
struct RoomCreateContentFields {
room_version: Option<Raw<RoomVersionId>>,
creator: Option<Raw<IgnoredAny>>,
}
info!("start m.room.create check");
// If it has any previous events, reject
if incoming_event.prev_events().next().is_some() {
warn!("the room creation event had previous events");
return Ok(false);
}
// If the domain of the room_id does not match the domain of the sender, reject
if incoming_event.room_id().server_name() != sender.server_name() {
warn!("creation events server does not match sender");
return Ok(false); // creation events room id does not match senders
}
let content: RoomCreateContentFields = from_json_str(incoming_event.content().get())?;
// If content.room_version is present and is not a recognized version, reject
if content.room_version.map(|v| v.deserialize().is_err()).unwrap_or(false) {
warn!("invalid room version found in m.room.create event");
return Ok(false);
}
// If content has no creator field, reject
if content.creator.is_none() {
warn!("no creator field found in m.room.create content");
return Ok(false);
}
info!("m.room.create event was allowed");
return Ok(true);
}
/*
// TODO: In the past this code caused problems federating with synapse, maybe this has been
// resolved already. Needs testing.
//
// 2. Reject if auth_events
// a. auth_events cannot have duplicate keys since it's a BTree
// b. All entries are valid auth events according to spec
let expected_auth = auth_types_for_event(
incoming_event.kind,
sender,
incoming_event.state_key,
incoming_event.content().clone(),
);
dbg!(&expected_auth);
for ev_key in auth_events.keys() {
// (b)
if !expected_auth.contains(ev_key) {
warn!("auth_events contained invalid auth event");
return Ok(false);
}
}
*/
let room_create_event = match fetch_state(&StateEventType::RoomCreate, "") {
None => {
warn!("no m.room.create event in auth chain");
return Ok(false);
}
Some(e) => e,
};
// 3. If event does not have m.room.create in auth_events reject
if !incoming_event.auth_events().any(|id| id.borrow() == room_create_event.event_id().borrow())
{
warn!("no m.room.create event in auth events");
return Ok(false);
}
// [synapse] checks for federation here
// Only in some room versions 6 and below
if room_version.special_case_aliases_auth {
// 4. If type is m.room.aliases
if *incoming_event.event_type() == RoomEventType::RoomAliases {
info!("starting m.room.aliases check");
// If sender's domain doesn't matches state_key, reject
if incoming_event.state_key() != Some(sender.server_name().as_str()) {
warn!("state_key does not match sender");
return Ok(false);
}
info!("m.room.aliases event was allowed");
return Ok(true);
}
}
// If type is m.room.member
let power_levels_event = fetch_state(&StateEventType::RoomPowerLevels, "");
let sender_member_event = fetch_state(&StateEventType::RoomMember, sender.as_str());
if *incoming_event.event_type() == RoomEventType::RoomMember {
info!("starting m.room.member check");
let state_key = match incoming_event.state_key() {
None => {
warn!("no statekey in member event");
return Ok(false);
}
Some(s) => s,
};
let content: RoomMemberContentFields = from_json_str(incoming_event.content().get())?;
if content.membership.as_ref().and_then(|m| m.deserialize().ok()).is_none() {
warn!("no valid membership field found for m.room.member event content");
return Ok(false);
}
let target_user =
<&UserId>::try_from(state_key).map_err(|e| Error::InvalidPdu(format!("{}", e)))?;
let user_for_join_auth =
content.join_authorised_via_users_server.as_ref().and_then(|u| u.deserialize().ok());
let user_for_join_auth_membership = user_for_join_auth
.as_ref()
.and_then(|auth_user| fetch_state(&StateEventType::RoomMember, auth_user.as_str()))
.and_then(|mem| from_json_str::<GetMembership>(mem.content().get()).ok())
.map(|mem| mem.membership)
.unwrap_or(MembershipState::Leave);
if !valid_membership_change(
room_version,
target_user,
fetch_state(&StateEventType::RoomMember, target_user.as_str()).as_ref(),
sender,
sender_member_event.as_ref(),
&incoming_event,
current_third_party_invite,
power_levels_event.as_ref(),
fetch_state(&StateEventType::RoomJoinRules, "").as_ref(),
user_for_join_auth.as_deref(),
&user_for_join_auth_membership,
room_create_event,
)? {
return Ok(false);
}
info!("m.room.member event was allowed");
return Ok(true);
}
// If the sender's current membership state is not join, reject
let sender_member_event = match sender_member_event {
Some(mem) => mem,
None => {
warn!("sender not found in room");
return Ok(false);
}
};
let sender_membership_event_content: RoomMemberContentFields =
from_json_str(sender_member_event.content().get())?;
let membership_state = sender_membership_event_content
.membership
.expect("we should test before that this field exists")
.deserialize()?;
if !matches!(membership_state, MembershipState::Join) {
warn!("sender's membership is not join");
return Ok(false);
}
// If type is m.room.third_party_invite
let sender_power_level = if let Some(pl) = &power_levels_event {
if let Ok(content) = from_json_str::<PowerLevelsContentFields>(pl.content().get()) {
if let Some(level) = content.users.get(sender) {
*level
} else {
content.users_default
}
} else {
int!(0) // TODO if this fails DB error?
}
} else {
// If no power level event found the creator gets 100 everyone else gets 0
from_json_str::<RoomCreateEventContent>(room_create_event.content().get())
.ok()
.and_then(|create| (create.creator == *sender).then(|| int!(100)))
.unwrap_or_default()
};
// Allow if and only if sender's current power level is greater than
// or equal to the invite level
if *incoming_event.event_type() == RoomEventType::RoomThirdPartyInvite {
let invite_level = match &power_levels_event {
Some(power_levels) => {
from_json_str::<PowerLevelsContentInvite>(power_levels.content().get())?.invite
}
None => int!(50),
};
if sender_power_level < invite_level {
warn!("sender's cannot send invites in this room");
return Ok(false);
}
}
// If the event type's required power level is greater than the sender's power level, reject
// If the event has a state_key that starts with an @ and does not match the sender, reject.
if !can_send_event(&incoming_event, power_levels_event.as_ref(), sender_power_level) {
warn!("user cannot send event");
return Ok(false);
}
// If type is m.room.power_levels
if *incoming_event.event_type() == RoomEventType::RoomPowerLevels {
info!("starting m.room.power_levels check");
if let Some(required_pwr_lvl) = check_power_levels(
room_version,
&incoming_event,
power_levels_event.as_ref(),
sender_power_level,
) {
if !required_pwr_lvl {
warn!("power level was not allowed");
return Ok(false);
}
} else {
warn!("power level was not allowed");
return Ok(false);
}
info!("power levels event allowed");
}
// Room version 3: Redaction events are always accepted (provided the event is allowed by
// `events` and `events_default` in the power levels). However, servers should not apply or
// send redaction's to clients until both the redaction event and original event have been
// seen, and are valid. Servers should only apply redaction's to events where the sender's
// domains match, or the sender of the redaction has the appropriate permissions per the
// power levels.
if room_version.extra_redaction_checks
&& *incoming_event.event_type() == RoomEventType::RoomRedaction
{
#[derive(Deserialize)]
struct PowerLevelsContentRedact {
redact: Int,
}
let redact_level = power_levels_event
.and_then(|pl| from_json_str::<PowerLevelsContentRedact>(pl.content().get()).ok())
.map(|c| c.redact)
.unwrap_or_else(|| int!(50));
if !check_redaction(room_version, incoming_event, sender_power_level, redact_level)? {
return Ok(false);
}
}
info!("allowing event passed all checks");
Ok(true)
}
// TODO deserializing the member, power, join_rules event contents is done in conduit
// just before this is called. Could they be passed in?
/// Does the user who sent this member event have required power levels to do so.
///
/// * `user` - Information about the membership event and user making the request.
/// * `auth_events` - The set of auth events that relate to a membership event.
///
/// This is generated by calling `auth_types_for_event` with the membership event and the current
/// State.
#[allow(clippy::too_many_arguments)]
fn valid_membership_change(
room_version: &RoomVersion,
target_user: &UserId,
target_user_membership_event: Option<impl Event>,
sender: &UserId,
sender_membership_event: Option<impl Event>,
current_event: impl Event,
current_third_party_invite: Option<impl Event>,
power_levels_event: Option<impl Event>,
join_rules_event: Option<impl Event>,
user_for_join_auth: Option<&UserId>,
user_for_join_auth_membership: &MembershipState,
create_room: impl Event,
) -> Result<bool> {
#[derive(Deserialize)]
struct GetThirdPartyInvite {
third_party_invite: Option<Raw<ThirdPartyInvite>>,
}
let content = current_event.content();
let target_membership = from_json_str::<GetMembership>(content.get())?.membership;
let third_party_invite =
from_json_str::<GetThirdPartyInvite>(content.get())?.third_party_invite;
let sender_membership = match &sender_membership_event {
Some(pdu) => from_json_str::<GetMembership>(pdu.content().get())?.membership,
None => MembershipState::Leave,
};
let sender_is_joined = sender_membership == MembershipState::Join;
let target_user_current_membership = match &target_user_membership_event {
Some(pdu) => from_json_str::<GetMembership>(pdu.content().get())?.membership,
None => MembershipState::Leave,
};
let power_levels: RoomPowerLevelsEventContent = match &power_levels_event {
Some(ev) => from_json_str(ev.content().get())?,
None => RoomPowerLevelsEventContent::default(),
};
let sender_power = power_levels
.users
.get(sender)
.or_else(|| sender_is_joined.then(|| &power_levels.users_default));
let target_power = power_levels.users.get(target_user).or_else(|| {
(target_membership == MembershipState::Join).then(|| &power_levels.users_default)
});
let mut join_rules = JoinRule::Invite;
if let Some(jr) = &join_rules_event {
join_rules = from_json_str::<RoomJoinRulesEventContent>(jr.content().get())?.join_rule;
}
let power_levels_event_id = power_levels_event.as_ref().map(|e| e.event_id());
let sender_membership_event_id = sender_membership_event.as_ref().map(|e| e.event_id());
let target_user_membership_event_id =
target_user_membership_event.as_ref().map(|e| e.event_id());
let user_for_join_auth_is_valid = if let Some(user_for_join_auth) = user_for_join_auth {
// Is the authorised user allowed to invite users into this room
let (auth_user_pl, invite_level) = if let Some(pl) = &power_levels_event {
// TODO Refactor all powerlevel parsing
let invite = match from_json_str::<PowerLevelsContentInvite>(pl.content().get()) {
Ok(power_levels) => power_levels.invite,
_ => int!(50),
};
if let Ok(content) = from_json_str::<PowerLevelsContentFields>(pl.content().get()) {
let user_pl = if let Some(level) = content.users.get(user_for_join_auth) {
*level
} else {
content.users_default
};
(user_pl, invite)
} else {
(int!(0), invite)
}
} else {
(int!(0), int!(0))
};
(user_for_join_auth_membership == &MembershipState::Join) && (auth_user_pl >= invite_level)
} else {
// No auth user was given
false
};
Ok(match target_membership {
MembershipState::Join => {
// 1. If the only previous event is an m.room.create and the state_key is the creator,
// allow
let mut prev_events = current_event.prev_events();
let prev_event_is_create_event = prev_events
.next()
.map(|event_id| event_id.borrow() == create_room.event_id().borrow())
.unwrap_or(false);
let no_more_prev_events = prev_events.next().is_none();
if prev_event_is_create_event && no_more_prev_events {
let create_content =
from_json_str::<RoomCreateEventContent>(create_room.content().get())?;
if create_content.creator == sender && create_content.creator == target_user {
return Ok(true);
}
}
if sender != target_user {
// If the sender does not match state_key, reject.
warn!("Can't make other user join");
false
} else if let MembershipState::Ban = target_user_current_membership {
// If the sender is banned, reject.
warn!(?target_user_membership_event_id, "Banned user can't join");
false
} else if (join_rules == JoinRule::Invite
|| room_version.allow_knocking && join_rules == JoinRule::Knock)
// If the join_rule is invite then allow if membership state is invite or join
&& (target_user_current_membership == MembershipState::Join
|| target_user_current_membership == MembershipState::Invite)
{
true
} else if room_version.restricted_join_rules
&& matches!(join_rules, JoinRule::Restricted(_))
{
// If the join_rule is restricted
if matches!(
target_user_current_membership,
MembershipState::Invite | MembershipState::Join
) {
// If membership state is join or invite, allow.
true
} else {
// If the join_authorised_via_users_server key in content is not a user with
// sufficient permission to invite other users, reject.
// Otherwise, allow.
user_for_join_auth_is_valid
}
} else {
// If the join_rule is public, allow.
// Otherwise, reject.
join_rules == JoinRule::Public
}
}
MembershipState::Invite => {
// If content has third_party_invite key
if let Some(tp_id) = third_party_invite.and_then(|i| i.deserialize().ok()) {
if target_user_current_membership == MembershipState::Ban {
warn!(?target_user_membership_event_id, "Can't invite banned user");
false
} else {
let allow = verify_third_party_invite(
Some(target_user),
sender,
&tp_id,
current_third_party_invite,
);
if !allow {
warn!("Third party invite invalid");
}
allow
}
} else if !sender_is_joined
|| target_user_current_membership == MembershipState::Join
|| target_user_current_membership == MembershipState::Ban
{
warn!(
?target_user_membership_event_id,
?sender_membership_event_id,
"Can't invite user if sender not joined or the user is currently joined or \
banned",
);
false
} else {
let allow = sender_power.filter(|&p| p >= &power_levels.invite).is_some();
if !allow {
warn!(
?target_user_membership_event_id,
?power_levels_event_id,
"User does not have enough power to invite",
);
}
allow
}
}
MembershipState::Leave => {
if sender == target_user {
let allow = target_user_current_membership == MembershipState::Join
|| target_user_current_membership == MembershipState::Invite;
if !allow {
warn!(?target_user_membership_event_id, "Can't leave if not invited or joined");
}
allow
} else if !sender_is_joined
|| target_user_current_membership == MembershipState::Ban
&& sender_power.filter(|&p| p < &power_levels.ban).is_some()
{
warn!(
?target_user_membership_event_id,
?sender_membership_event_id,
"Can't kick if sender not joined or user is already banned",
);
false
} else {
let allow = sender_power.filter(|&p| p >= &power_levels.kick).is_some()
&& target_power < sender_power;
if !allow {
warn!(
?target_user_membership_event_id,
?power_levels_event_id,
"User does not have enough power to kick",
);
}
allow
}
}
MembershipState::Ban => {
if !sender_is_joined {
warn!(?sender_membership_event_id, "Can't ban user if sender is not joined");
false
} else {
let allow = sender_power.filter(|&p| p >= &power_levels.ban).is_some()
&& target_power < sender_power;
if !allow {
warn!(
?target_user_membership_event_id,
?power_levels_event_id,
"User does not have enough power to ban",
);
}
allow
}
}
MembershipState::Knock if room_version.allow_knocking => {
// 1. If the `join_rule` is anything other than `knock`, reject.
if join_rules != JoinRule::Knock {
warn!("Join rule is not set to knock, knocking is not allowed");
false
} else {
// 2. If `sender` does not match `state_key`, reject.
// 3. If the `sender`'s current membership is not `ban`, `invite`, or `join`, allow.
// 4. Otherwise, reject.
if sender != target_user {
warn!(
?sender,
?target_user,
"Can't make another user join, sender did not match target"
);
false
} else if matches!(
sender_membership,
MembershipState::Ban | MembershipState::Invite | MembershipState::Join
) {
warn!(
?target_user_membership_event_id,
"Membership state of ban, invite, or join are invalid",
);
false
} else {
true
}
}
}
_ => {
warn!("Unknown membership transition");
false
}
})
}
/// Is the user allowed to send a specific event based on the rooms power levels.
///
/// Does the event have the correct userId as its state_key if it's not the "" state_key.
fn can_send_event(event: impl Event, ple: Option<impl Event>, user_level: Int) -> bool {
let event_type_power_level = get_send_level(event.event_type(), event.state_key(), ple);
debug!("{} ev_type {} usr {}", event.event_id(), event_type_power_level, user_level);
if user_level < event_type_power_level {
return false;
}
if event.state_key().map_or(false, |k| k.starts_with('@'))
&& event.state_key() != Some(event.sender().as_str())
{
return false; // permission required to post in this room
}
true
}
/// Confirm that the event sender has the required power levels.
fn check_power_levels(
room_version: &RoomVersion,
power_event: impl Event,
previous_power_event: Option<impl Event>,
user_level: Int,
) -> Option<bool> {
match power_event.state_key() {
Some("") => {}
Some(key) => {
error!("m.room.power_levels event has non-empty state key: {}", key);
return None;
}
None => {
error!("check_power_levels requires an m.room.power_levels *state* event argument");
return None;
}
}
let current_state = match previous_power_event {
Some(current_state) => current_state,
// If there is no previous m.room.power_levels event in the room, allow
None => return Some(true),
};
// If users key in content is not a dictionary with keys that are valid user IDs
// with values that are integers (or a string that is an integer), reject.
let user_content =
from_json_str::<RoomPowerLevelsEventContent>(power_event.content().get()).unwrap();
let current_content =
from_json_str::<RoomPowerLevelsEventContent>(current_state.content().get()).unwrap();
// Validation of users is done in Ruma, synapse for loops validating user_ids and integers here
info!("validation of power event finished");
let mut user_levels_to_check = BTreeSet::new();
let old_list = &current_content.users;
let user_list = &user_content.users;
for user in old_list.keys().chain(user_list.keys()) {
let user: &UserId = user;
user_levels_to_check.insert(user);
}
debug!("users to check {:?}", user_levels_to_check);
let mut event_levels_to_check = BTreeSet::new();
let old_list = &current_content.events;
let new_list = &user_content.events;
for ev_id in old_list.keys().chain(new_list.keys()) {
event_levels_to_check.insert(ev_id);
}
debug!("events to check {:?}", event_levels_to_check);
let old_state = &current_content;
let new_state = &user_content;
// synapse does not have to split up these checks since we can't combine UserIds and
// EventTypes we do 2 loops
// UserId loop
for user in user_levels_to_check {
let old_level = old_state.users.get(user);
let new_level = new_state.users.get(user);
if old_level.is_some() && new_level.is_some() && old_level == new_level {
continue;
}
// If the current value is equal to the sender's current power level, reject
if user != power_event.sender() && old_level == Some(&user_level) {
warn!("m.room.power_level cannot remove ops == to own");
return Some(false); // cannot remove ops level == to own
}
// If the current value is higher than the sender's current power level, reject
// If the new value is higher than the sender's current power level, reject
let old_level_too_big = old_level > Some(&user_level);
let new_level_too_big = new_level > Some(&user_level);
if old_level_too_big || new_level_too_big {
warn!("m.room.power_level failed to add ops > than own");
return Some(false); // cannot add ops greater than own
}
}
// EventType loop
for ev_type in event_levels_to_check {
let old_level = old_state.events.get(ev_type);
let new_level = new_state.events.get(ev_type);
if old_level.is_some() && new_level.is_some() && old_level == new_level {
continue;
}
// If the current value is higher than the sender's current power level, reject
// If the new value is higher than the sender's current power level, reject
let old_level_too_big = old_level > Some(&user_level);
let new_level_too_big = new_level > Some(&user_level);
if old_level_too_big || new_level_too_big {
warn!("m.room.power_level failed to add ops > than own");
return Some(false); // cannot add ops greater than own
}
}
// Notifications, currently there is only @room
if room_version.limit_notifications_power_levels {
let old_level = old_state.notifications.room;
let new_level = new_state.notifications.room;
if old_level != new_level {
// If the current value is higher than the sender's current power level, reject
// If the new value is higher than the sender's current power level, reject
let old_level_too_big = old_level > user_level;
let new_level_too_big = new_level > user_level;
if old_level_too_big || new_level_too_big {
warn!("m.room.power_level failed to add ops > than own");
return Some(false); // cannot add ops greater than own
}
}
}
let levels =
["users_default", "events_default", "state_default", "ban", "redact", "kick", "invite"];
let old_state = serde_json::to_value(old_state).unwrap();
let new_state = serde_json::to_value(new_state).unwrap();
for lvl_name in &levels {
if let Some((old_lvl, new_lvl)) = get_deserialize_levels(&old_state, &new_state, lvl_name) {
let old_level_too_big = old_lvl > user_level;
let new_level_too_big = new_lvl > user_level;
if old_level_too_big || new_level_too_big {
warn!("cannot add ops > than own");
return Some(false);
}
}
}
Some(true)
}
fn get_deserialize_levels(
old: &serde_json::Value,
new: &serde_json::Value,
name: &str,
) -> Option<(Int, Int)> {
Some((
serde_json::from_value(old.get(name)?.clone()).ok()?,
serde_json::from_value(new.get(name)?.clone()).ok()?,
))
}
/// Does the event redacting come from a user with enough power to redact the given event.
fn check_redaction(
_room_version: &RoomVersion,
redaction_event: impl Event,
user_level: Int,
redact_level: Int,
) -> Result<bool> {
if user_level >= redact_level {
info!("redaction allowed via power levels");
return Ok(true);
}
// If the domain of the event_id of the event being redacted is the same as the
// domain of the event_id of the m.room.redaction, allow
if redaction_event.event_id().borrow().server_name()
== redaction_event.redacts().as_ref().and_then(|&id| id.borrow().server_name())
{
info!("redaction event allowed via room version 1 rules");
return Ok(true);
}
Ok(false)
}
/// Helper function to fetch the power level needed to send an event of type
/// `e_type` based on the rooms "m.room.power_level" event.
fn get_send_level(
e_type: &RoomEventType,
state_key: Option<&str>,
power_lvl: Option<impl Event>,
) -> Int {
power_lvl
.and_then(|ple| {
from_json_str::<RoomPowerLevelsEventContent>(ple.content().get())
.map(|content| {
content.events.get(e_type).copied().unwrap_or_else(|| {
if state_key.is_some() {
content.state_default
} else {
content.events_default
}
})
})
.ok()
})
.unwrap_or_else(|| if state_key.is_some() { int!(50) } else { int!(0) })
}
fn verify_third_party_invite(
target_user: Option<&UserId>,
sender: &UserId,
tp_id: &ThirdPartyInvite,
current_third_party_invite: Option<impl Event>,
) -> bool {
// 1. Check for user being banned happens before this is called
// checking for mxid and token keys is done by ruma when deserializing
// The state key must match the invitee
if target_user != Some(&tp_id.signed.mxid) {
return false;
}
// If there is no m.room.third_party_invite event in the current room state with state_key
// matching token, reject
let current_tpid = match current_third_party_invite {
Some(id) => id,
None => return false,
};
if current_tpid.state_key() != Some(&tp_id.signed.token) {
return false;
}
if sender != current_tpid.sender() {
return false;
}
// If any signature in signed matches any public key in the m.room.third_party_invite event,
// allow
let tpid_ev =
match from_json_str::<RoomThirdPartyInviteEventContent>(current_tpid.content().get()) {
Ok(ev) => ev,
Err(_) => return false,
};
let decoded_invite_token = match Base64::parse(&tp_id.signed.token) {
Ok(tok) => tok,
// FIXME: Log a warning?
Err(_) => return false,
};
// A list of public keys in the public_keys field
for key in tpid_ev.public_keys.unwrap_or_default() {
if key.public_key == decoded_invite_token {
return true;
}
}
// A single public key in the public_key field
tpid_ev.public_key == decoded_invite_token
}
#[cfg(test)]
mod tests {
use std::sync::Arc;
use ruma_common::events::{
room::{
join_rules::{
AllowRule, JoinRule, Restricted, RoomJoinRulesEventContent, RoomMembership,
},
member::{MembershipState, RoomMemberEventContent},
},
RoomEventType, StateEventType,
};
use serde_json::value::to_raw_value as to_raw_json_value;
use crate::{
event_auth::valid_membership_change,
test_utils::{
alice, charlie, ella, event_id, member_content_ban, member_content_join, room_id,
to_pdu_event, PduEvent, INITIAL_EVENTS, INITIAL_EVENTS_CREATE_ROOM,
},
Event, EventTypeExt, RoomVersion, StateMap,
};
#[test]
fn test_ban_pass() {
let _ =
tracing::subscriber::set_default(tracing_subscriber::fmt().with_test_writer().finish());
let events = INITIAL_EVENTS();
let auth_events = events
.values()
.map(|ev| (ev.event_type().with_state_key(ev.state_key().unwrap()), Arc::clone(ev)))
.collect::<StateMap<_>>();
let requester = to_pdu_event(
"HELLO",
alice(),
RoomEventType::RoomMember,
Some(charlie().as_str()),
member_content_ban(),
&[],
&["IMC"],
);
let fetch_state = |ty, key| auth_events.get(&(ty, key)).cloned();
let target_user = charlie();
let sender = alice();
assert!(valid_membership_change(
&RoomVersion::V6,
target_user,
fetch_state(StateEventType::RoomMember, target_user.to_string()),
sender,
fetch_state(StateEventType::RoomMember, sender.to_string()),
&requester,
None::<PduEvent>,
fetch_state(StateEventType::RoomPowerLevels, "".to_owned()),
fetch_state(StateEventType::RoomJoinRules, "".to_owned()),
None,
&MembershipState::Leave,
fetch_state(StateEventType::RoomCreate, "".to_owned()).unwrap(),
)
.unwrap());
}
#[test]
fn test_join_non_creator() {
let _ =
tracing::subscriber::set_default(tracing_subscriber::fmt().with_test_writer().finish());
let events = INITIAL_EVENTS_CREATE_ROOM();
let auth_events = events
.values()
.map(|ev| (ev.event_type().with_state_key(ev.state_key().unwrap()), Arc::clone(ev)))
.collect::<StateMap<_>>();
let requester = to_pdu_event(
"HELLO",
charlie(),
RoomEventType::RoomMember,
Some(charlie().as_str()),
member_content_join(),
&["CREATE"],
&["CREATE"],
);
let fetch_state = |ty, key| auth_events.get(&(ty, key)).cloned();
let target_user = charlie();
let sender = charlie();
assert!(!valid_membership_change(
&RoomVersion::V6,
target_user,
fetch_state(StateEventType::RoomMember, target_user.to_string()),
sender,
fetch_state(StateEventType::RoomMember, sender.to_string()),
&requester,
None::<PduEvent>,
fetch_state(StateEventType::RoomPowerLevels, "".to_owned()),
fetch_state(StateEventType::RoomJoinRules, "".to_owned()),
None,
&MembershipState::Leave,
fetch_state(StateEventType::RoomCreate, "".to_owned()).unwrap(),
)
.unwrap());
}
#[test]
fn test_join_creator() {
let _ =
tracing::subscriber::set_default(tracing_subscriber::fmt().with_test_writer().finish());
let events = INITIAL_EVENTS_CREATE_ROOM();
let auth_events = events
.values()
.map(|ev| (ev.event_type().with_state_key(ev.state_key().unwrap()), Arc::clone(ev)))
.collect::<StateMap<_>>();
let requester = to_pdu_event(
"HELLO",
alice(),
RoomEventType::RoomMember,
Some(alice().as_str()),
member_content_join(),
&["CREATE"],
&["CREATE"],
);
let fetch_state = |ty, key| auth_events.get(&(ty, key)).cloned();
let target_user = alice();
let sender = alice();
assert!(valid_membership_change(
&RoomVersion::V6,
target_user,
fetch_state(StateEventType::RoomMember, target_user.to_string()),
sender,
fetch_state(StateEventType::RoomMember, sender.to_string()),
&requester,
None::<PduEvent>,
fetch_state(StateEventType::RoomPowerLevels, "".to_owned()),
fetch_state(StateEventType::RoomJoinRules, "".to_owned()),
None,
&MembershipState::Leave,
fetch_state(StateEventType::RoomCreate, "".to_owned()).unwrap(),
)
.unwrap());
}
#[test]
fn test_ban_fail() {
let _ =
tracing::subscriber::set_default(tracing_subscriber::fmt().with_test_writer().finish());
let events = INITIAL_EVENTS();
let auth_events = events
.values()
.map(|ev| (ev.event_type().with_state_key(ev.state_key().unwrap()), Arc::clone(ev)))
.collect::<StateMap<_>>();
let requester = to_pdu_event(
"HELLO",
charlie(),
RoomEventType::RoomMember,
Some(alice().as_str()),
member_content_ban(),
&[],
&["IMC"],
);
let fetch_state = |ty, key| auth_events.get(&(ty, key)).cloned();
let target_user = alice();
let sender = charlie();
assert!(!valid_membership_change(
&RoomVersion::V6,
target_user,
fetch_state(StateEventType::RoomMember, target_user.to_string()),
sender,
fetch_state(StateEventType::RoomMember, sender.to_string()),
&requester,
None::<PduEvent>,
fetch_state(StateEventType::RoomPowerLevels, "".to_owned()),
fetch_state(StateEventType::RoomJoinRules, "".to_owned()),
None,
&MembershipState::Leave,
fetch_state(StateEventType::RoomCreate, "".to_owned()).unwrap(),
)
.unwrap());
}
#[test]
fn test_restricted_join_rule() {
let _ =
tracing::subscriber::set_default(tracing_subscriber::fmt().with_test_writer().finish());
let mut events = INITIAL_EVENTS();
*events.get_mut(&event_id("IJR")).unwrap() = to_pdu_event(
"IJR",
alice(),
RoomEventType::RoomJoinRules,
Some(""),
to_raw_json_value(&RoomJoinRulesEventContent::new(JoinRule::Restricted(
Restricted::new(vec![AllowRule::RoomMembership(RoomMembership::new(
room_id().to_owned(),
))]),
)))
.unwrap(),
&["CREATE", "IMA", "IPOWER"],
&["IPOWER"],
);
let mut member = RoomMemberEventContent::new(MembershipState::Join);
member.join_authorized_via_users_server = Some(alice().to_owned());
let auth_events = events
.values()
.map(|ev| (ev.event_type().with_state_key(ev.state_key().unwrap()), Arc::clone(ev)))
.collect::<StateMap<_>>();
let requester = to_pdu_event(
"HELLO",
ella(),
RoomEventType::RoomMember,
Some(ella().as_str()),
to_raw_json_value(&RoomMemberEventContent::new(MembershipState::Join)).unwrap(),
&["CREATE", "IJR", "IPOWER", "new"],
&["new"],
);
let fetch_state = |ty, key| auth_events.get(&(ty, key)).cloned();
let target_user = ella();
let sender = ella();
assert!(valid_membership_change(
&RoomVersion::V9,
target_user,
fetch_state(StateEventType::RoomMember, target_user.to_string()),
sender,
fetch_state(StateEventType::RoomMember, sender.to_string()),
&requester,
None::<PduEvent>,
fetch_state(StateEventType::RoomPowerLevels, "".to_owned()),
fetch_state(StateEventType::RoomJoinRules, "".to_owned()),
Some(alice()),
&MembershipState::Join,
fetch_state(StateEventType::RoomCreate, "".to_owned()).unwrap(),
)
.unwrap());
assert!(!valid_membership_change(
&RoomVersion::V9,
target_user,
fetch_state(StateEventType::RoomMember, target_user.to_string()),
sender,
fetch_state(StateEventType::RoomMember, sender.to_string()),
&requester,
None::<PduEvent>,
fetch_state(StateEventType::RoomPowerLevels, "".to_owned()),
fetch_state(StateEventType::RoomJoinRules, "".to_owned()),
Some(ella()),
&MembershipState::Leave,
fetch_state(StateEventType::RoomCreate, "".to_owned()).unwrap(),
)
.unwrap());
}
#[test]
fn test_knock() {
let _ =
tracing::subscriber::set_default(tracing_subscriber::fmt().with_test_writer().finish());
let mut events = INITIAL_EVENTS();
*events.get_mut(&event_id("IJR")).unwrap() = to_pdu_event(
"IJR",
alice(),
RoomEventType::RoomJoinRules,
Some(""),
to_raw_json_value(&RoomJoinRulesEventContent::new(JoinRule::Knock)).unwrap(),
&["CREATE", "IMA", "IPOWER"],
&["IPOWER"],
);
let auth_events = events
.values()
.map(|ev| (ev.event_type().with_state_key(ev.state_key().unwrap()), Arc::clone(ev)))
.collect::<StateMap<_>>();
let requester = to_pdu_event(
"HELLO",
ella(),
RoomEventType::RoomMember,
Some(ella().as_str()),
to_raw_json_value(&RoomMemberEventContent::new(MembershipState::Knock)).unwrap(),
&[],
&["IMC"],
);
let fetch_state = |ty, key| auth_events.get(&(ty, key)).cloned();
let target_user = ella();
let sender = ella();
assert!(valid_membership_change(
&RoomVersion::V7,
target_user,
fetch_state(StateEventType::RoomMember, target_user.to_string()),
sender,
fetch_state(StateEventType::RoomMember, sender.to_string()),
&requester,
None::<PduEvent>,
fetch_state(StateEventType::RoomPowerLevels, "".to_owned()),
fetch_state(StateEventType::RoomJoinRules, "".to_owned()),
None,
&MembershipState::Leave,
fetch_state(StateEventType::RoomCreate, "".to_owned()).unwrap(),
)
.unwrap());
}
}