Start implementing /join for room aliases for rooms the server is not in. (#115)

* Start implementing the join room API

* Hacks to get join room working

* Make the TLS fingerprint configurable

* Fix the client API proxy to handle '#' correctly

* Return a 200 OK response

* Write the join event along with current state to the room server

* Comment on the error handling

* Fix typos

* Fix tab

* Add TODO for moving authEventIDs to gomatrixserverlib

* Comment on why we ignore the key ID argument for local keys

* Avoid 'preceeded'

* Neaten the control flow

* Neaten the control flow even more

* Return pointers

* Rename err to lastErr for the loop

vendor/manifest

@@ -98,7 +98,7 @@
 		{
 			"importpath": "github.com/matrix-org/gomatrixserverlib",
 			"repository": "https://github.com/matrix-org/gomatrixserverlib",
-			"revision": "9cefcd6c3a00bff51e719a33e19a16edf52cdd6f",
+			"revision": "c396ef3cc1e546729f7052f1f48e345cc59269f4",
 			"branch": "master"
 		},
 		{

vendor/src/github.com/matrix-org/gomatrixserverlib/event.go

@@ -386,7 +386,7 @@ func (e Event) CheckFields() error {
 		// are allowed to have a different sender because they have the same
 		// sender as the "m.room.third_party_invite" event they derived from.
 		// https://github.com/matrix-org/synapse/blob/v0.21.0/synapse/event_auth.py#L58-L64
-		if e.fields.Type != "m.room.member" {
+		if e.fields.Type != MRoomMember {
 			return fmt.Errorf(
 				"gomatrixserverlib: sender domain doesn't match origin: %q != %q",
 				eventDomain, e.fields.Origin,

vendor/src/github.com/matrix-org/gomatrixserverlib/eventauth.go

@@ -28,6 +28,22 @@ const (
 	leave  = "leave"
 	invite = "invite"
 	public = "public"
+	// MRoomCreate https://matrix.org/docs/spec/client_server/r0.2.0.html#m-room-create
+	MRoomCreate = "m.room.create"
+	// MRoomJoinRules https://matrix.org/docs/spec/client_server/r0.2.0.html#m-room-join-rules
+	MRoomJoinRules = "m.room.join_rules"
+	// MRoomPowerLevels https://matrix.org/docs/spec/client_server/r0.2.0.html#m-room-power-levels
+	MRoomPowerLevels = "m.room.power_levels"
+	// MRoomMember https://matrix.org/docs/spec/client_server/r0.2.0.html#m-room-member
+	MRoomMember = "m.room.member"
+	// MRoomThirdPartyInvite https://matrix.org/docs/spec/client_server/r0.2.0.html#m-room-third-party-invite
+	MRoomThirdPartyInvite = "m.room.third_party_invite"
+	// MRoomAliases https://matrix.org/docs/spec/client_server/r0.2.0.html#m-room-aliases
+	MRoomAliases = "m.room.aliases"
+	// MRoomHistoryVisibility https://matrix.org/docs/spec/client_server/r0.2.0.html#m-room-history-visibility
+	MRoomHistoryVisibility = "m.room.history_visibility"
+	// MRoomRedaction https://matrix.org/docs/spec/client_server/r0.2.0.html#id21
+	MRoomRedaction = "m.room.redaction"
 )
 
 // StateNeeded lists the event types and state_keys needed to authenticate an event.
@@ -47,19 +63,19 @@ type StateNeeded struct {
 // Tuples returns the needed state key tuples for performing auth on an event.
 func (s StateNeeded) Tuples() (res []StateKeyTuple) {
 	if s.Create {
-		res = append(res, StateKeyTuple{"m.room.create", ""})
+		res = append(res, StateKeyTuple{MRoomCreate, ""})
 	}
 	if s.JoinRules {
-		res = append(res, StateKeyTuple{"m.room.join_rules", ""})
+		res = append(res, StateKeyTuple{MRoomJoinRules, ""})
 	}
 	if s.PowerLevels {
-		res = append(res, StateKeyTuple{"m.room.power_levels", ""})
+		res = append(res, StateKeyTuple{MRoomPowerLevels, ""})
 	}
 	for _, userID := range s.Member {
-		res = append(res, StateKeyTuple{"m.room.member", userID})
+		res = append(res, StateKeyTuple{MRoomMember, userID})
 	}
 	for _, token := range s.ThirdPartyInvite {
-		res = append(res, StateKeyTuple{"m.room.third_party_invite", token})
+		res = append(res, StateKeyTuple{MRoomThirdPartyInvite, token})
 	}
 	return
 }
@@ -114,7 +130,7 @@ func (s StateNeeded) AuthEventReferences(provider AuthEventProvider) (refs []Eve
 func StateNeededForEventBuilder(builder *EventBuilder) (result StateNeeded, err error) {
 	// Extract the 'content' object from the event if it is m.room.member as we need to know 'membership'
 	var content *memberContent
-	if builder.Type == "m.room.member" {
+	if builder.Type == MRoomMember {
 		if err = json.Unmarshal(builder.Content, &content); err != nil {
 			err = errorf("unparsable member event content: %s", err.Error())
 			return
@@ -132,7 +148,7 @@ func StateNeededForAuth(events []Event) (result StateNeeded) {
 	for _, event := range events {
 		// Extract the 'content' object from the event if it is m.room.member as we need to know 'membership'
 		var content *memberContent
-		if event.Type() == "m.room.member" {
+		if event.Type() == MRoomMember {
 			c, err := newMemberContentFromEvent(event)
 			if err == nil {
 				content = &c
@@ -151,17 +167,17 @@ func StateNeededForAuth(events []Event) (result StateNeeded) {
 
 func accumulateStateNeeded(result *StateNeeded, eventType, sender string, stateKey *string, content *memberContent) (err error) {
 	switch eventType {
-	case "m.room.create":
+	case MRoomCreate:
 		// The create event doesn't require any state to authenticate.
 		// https://github.com/matrix-org/synapse/blob/v0.18.5/synapse/api/auth.py#L123
-	case "m.room.aliases":
+	case MRoomAliases:
 		// Alias events need:
 		//  * The create event.
 		//    https://github.com/matrix-org/synapse/blob/v0.18.5/synapse/api/auth.py#L128
 		// Alias events need no further authentication.
 		// https://github.com/matrix-org/synapse/blob/v0.18.5/synapse/api/auth.py#L160
 		result.Create = true
-	case "m.room.member":
+	case MRoomMember:
 		// Member events need:
 		//  * The previous membership of the target.
 		//    https://github.com/matrix-org/synapse/blob/v0.18.5/synapse/api/auth.py#L355
@@ -255,27 +271,27 @@ func (a *AuthEvents) AddEvent(event *Event) error {
 
 // Create implements AuthEventProvider
 func (a *AuthEvents) Create() (*Event, error) {
-	return a.events[StateKeyTuple{"m.room.create", ""}], nil
+	return a.events[StateKeyTuple{MRoomCreate, ""}], nil
 }
 
 // JoinRules implements AuthEventProvider
 func (a *AuthEvents) JoinRules() (*Event, error) {
-	return a.events[StateKeyTuple{"m.room.join_rules", ""}], nil
+	return a.events[StateKeyTuple{MRoomJoinRules, ""}], nil
 }
 
 // PowerLevels implements AuthEventProvider
 func (a *AuthEvents) PowerLevels() (*Event, error) {
-	return a.events[StateKeyTuple{"m.room.power_levels", ""}], nil
+	return a.events[StateKeyTuple{MRoomPowerLevels, ""}], nil
 }
 
 // Member implements AuthEventProvider
 func (a *AuthEvents) Member(stateKey string) (*Event, error) {
-	return a.events[StateKeyTuple{"m.room.member", stateKey}], nil
+	return a.events[StateKeyTuple{MRoomMember, stateKey}], nil
 }
 
 // ThirdPartyInvite implements AuthEventProvider
 func (a *AuthEvents) ThirdPartyInvite(stateKey string) (*Event, error) {
-	return a.events[StateKeyTuple{"m.room.third_party_invite", stateKey}], nil
+	return a.events[StateKeyTuple{MRoomThirdPartyInvite, stateKey}], nil
 }
 
 // NewAuthEvents returns an AuthEventProvider backed by the given events. New events can be added by
@@ -306,15 +322,15 @@ func errorf(message string, args ...interface{}) error {
 // If there was an error loading the auth events then it returns that error.
 func Allowed(event Event, authEvents AuthEventProvider) error {
 	switch event.Type() {
-	case "m.room.create":
+	case MRoomCreate:
 		return createEventAllowed(event)
-	case "m.room.aliases":
+	case MRoomAliases:
 		return aliasEventAllowed(event, authEvents)
-	case "m.room.member":
+	case MRoomMember:
 		return memberEventAllowed(event, authEvents)
-	case "m.room.power_levels":
+	case MRoomPowerLevels:
 		return powerLevelsEventAllowed(event, authEvents)
-	case "m.room.redaction":
+	case MRoomRedaction:
 		return redactEventAllowed(event, authEvents)
 	default:
 		return defaultEventAllowed(event, authEvents)

vendor/src/github.com/matrix-org/gomatrixserverlib/eventcontent.go

@@ -191,7 +191,7 @@ func (c *powerLevelContent) userLevel(userID string) int64 {
 
 // eventLevel returns the power level needed to send an event in the room.
 func (c *powerLevelContent) eventLevel(eventType string, isState bool) int64 {
-	if eventType == "m.room.third_party_invite" {
+	if eventType == MRoomThirdPartyInvite {
 		// Special case third_party_invite events to have the same level as
 		// m.room.member invite events.
 		// https://github.com/matrix-org/synapse/blob/v0.18.5/synapse/api/auth.py#L182

vendor/src/github.com/matrix-org/gomatrixserverlib/eventcrypto.go

@@ -201,9 +201,9 @@ func VerifyEventSignatures(events []Event, keyRing KeyRing) error {
 		}
 		toVerify = append(toVerify, v)
 
-		// "m.room.member" invite events are signed by both the server sending
+		// MRoomMember invite events are signed by both the server sending
 		// the invite and the server the invite is for.
-		if event.Type() == "m.room.member" && event.StateKey() != nil {
+		if event.Type() == MRoomMember && event.StateKey() != nil {
 			targetDomain, err := domainFromID(*event.StateKey())
 			if err != nil {
 				return err

vendor/src/github.com/matrix-org/gomatrixserverlib/federationtypes.go

@@ -34,6 +34,78 @@ type RespState struct {
 	AuthEvents []Event `json:"auth_chain"`
 }
 
+// Events combines the auth events and the state events and returns
+// them in an order where every event comes after its auth events.
+// Each event will only appear once in the output list.
+// Returns an error if there are missing auth events or if there is
+// a cycle in the auth events.
+func (r RespState) Events() ([]Event, error) {
+	eventsByID := map[string]*Event{}
+	// Collect a map of event reference to event
+	for i := range r.StateEvents {
+		eventsByID[r.StateEvents[i].EventID()] = &r.StateEvents[i]
+	}
+	for i := range r.AuthEvents {
+		eventsByID[r.AuthEvents[i].EventID()] = &r.AuthEvents[i]
+	}
+
+	queued := map[*Event]bool{}
+	outputted := map[*Event]bool{}
+	var result []Event
+	for _, event := range eventsByID {
+		if outputted[event] {
+			// If we've already written the event then we can skip it.
+			continue
+		}
+
+		// The code below does a depth first scan through the auth events
+		// looking for events that can be appended to the output.
+
+		// We use an explicit stack rather than using recursion so
+		// that we can check we aren't creating cycles.
+		stack := []*Event{event}
+
+	LoopProcessTopOfStack:
+		for len(stack) > 0 {
+			top := stack[len(stack)-1]
+			// Check if we can output the top of the stack.
+			// We can output it if we have outputted all of its auth_events.
+			for _, ref := range top.AuthEvents() {
+				authEvent := eventsByID[ref.EventID]
+				if authEvent == nil {
+					return nil, fmt.Errorf(
+						"gomatrixserverlib: missing auth event with ID %q for event %q",
+						ref.EventID, top.EventID(),
+					)
+				}
+				if outputted[authEvent] {
+					continue
+				}
+				if queued[authEvent] {
+					return nil, fmt.Errorf(
+						"gomatrixserverlib: auth event cycle for ID %q",
+						ref.EventID,
+					)
+				}
+				// If we haven't visited the auth event yet then we need to
+				// process it before processing the event currently on top of
+				// the stack.
+				stack = append(stack, authEvent)
+				queued[authEvent] = true
+				continue LoopProcessTopOfStack
+			}
+			// If we've processed all the auth events for the event on top of
+			// the stack then we can append it to the result and try processing
+			// the item below it in the stack.
+			result = append(result, *top)
+			outputted[top] = true
+			stack = stack[:len(stack)-1]
+		}
+	}
+
+	return result, nil
+}
+
 // Check that a response to /state is valid.
 func (r RespState) Check(keyRing KeyRing) error {
 	var allEvents []Event

vendor/src/github.com/matrix-org/gomatrixserverlib/redactevent.go

@@ -140,17 +140,17 @@ func redactEvent(eventJSON []byte) ([]byte, error) {
 	// Copy the content fields that we should keep for the event type.
 	// By default we copy nothing leaving the content object empty.
 	switch event.Type {
-	case "m.room.create":
+	case MRoomCreate:
 		newContent.createContent = event.Content.createContent
-	case "m.room.member":
+	case MRoomMember:
 		newContent.memberContent = event.Content.memberContent
-	case "m.room.join_rules":
+	case MRoomJoinRules:
 		newContent.joinRulesContent = event.Content.joinRulesContent
-	case "m.room.power_levels":
+	case MRoomPowerLevels:
 		newContent.powerLevelContent = event.Content.powerLevelContent
-	case "m.room.history_visibility":
+	case MRoomHistoryVisibility:
 		newContent.historyVisibilityContent = event.Content.historyVisibilityContent
-	case "m.room.aliases":
+	case MRoomAliases:
 		newContent.aliasesContent = event.Content.aliasesContent
 	}
 	// Replace the content with our new filtered content.

vendor/src/github.com/matrix-org/gomatrixserverlib/stateresolution.go

@@ -114,24 +114,24 @@ func (r *stateResolver) addConflicted(events []Event) {
 		// By default we add the event to a block in the others list.
 		blockList := &r.others
 		switch key.eventType {
-		case "m.room.create":
+		case MRoomCreate:
 			if key.stateKey == "" {
 				r.creates = append(r.creates, event)
 				continue
 			}
-		case "m.room.power_levels":
+		case MRoomPowerLevels:
 			if key.stateKey == "" {
 				r.powerLevels = append(r.powerLevels, event)
 				continue
 			}
-		case "m.room.join_rules":
+		case MRoomJoinRules:
 			if key.stateKey == "" {
 				r.joinRules = append(r.joinRules, event)
 				continue
 			}
-		case "m.room.member":
+		case MRoomMember:
 			blockList = &r.members
-		case "m.room.third_party_invite":
+		case MRoomThirdPartyInvite:
 			blockList = &r.thirdPartyInvites
 		}
 		// We need to find an entry for the state key in a block list.
@@ -153,21 +153,21 @@ func (r *stateResolver) addConflicted(events []Event) {
 // Add an event to the resolved auth events.
 func (r *stateResolver) addAuthEvent(event *Event) {
 	switch event.Type() {
-	case "m.room.create":
+	case MRoomCreate:
 		if event.StateKeyEquals("") {
 			r.resolvedCreate = event
 		}
-	case "m.room.power_levels":
+	case MRoomPowerLevels:
 		if event.StateKeyEquals("") {
 			r.resolvedPowerLevels = event
 		}
-	case "m.room.join_rules":
+	case MRoomJoinRules:
 		if event.StateKeyEquals("") {
 			r.resolvedJoinRules = event
 		}
-	case "m.room.member":
+	case MRoomMember:
 		r.resolvedMembers[*event.StateKey()] = event
-	case "m.room.third_party_invite":
+	case MRoomThirdPartyInvite:
 		r.resolvedThirdPartyInvites[*event.StateKey()] = event
 	default:
 		panic(fmt.Errorf("Unexpected auth event with type %q", event.Type()))
@@ -177,21 +177,21 @@ func (r *stateResolver) addAuthEvent(event *Event) {
 // Remove the auth event with the given type and state key.
 func (r *stateResolver) removeAuthEvent(eventType, stateKey string) {
 	switch eventType {
-	case "m.room.create":
+	case MRoomCreate:
 		if stateKey == "" {
 			r.resolvedCreate = nil
 		}
-	case "m.room.power_levels":
+	case MRoomPowerLevels:
 		if stateKey == "" {
 			r.resolvedPowerLevels = nil
 		}
-	case "m.room.join_rules":
+	case MRoomJoinRules:
 		if stateKey == "" {
 			r.resolvedJoinRules = nil
 		}
-	case "m.room.member":
+	case MRoomMember:
 		r.resolvedMembers[stateKey] = nil
-	case "m.room.third_party_invite":
+	case MRoomThirdPartyInvite:
 		r.resolvedThirdPartyInvites[stateKey] = nil
 	default:
 		panic(fmt.Errorf("Unexpected auth event with type %q", eventType))