Processing of pending invites on 3PID binding (#218)

* Add missing file headers

* Move the ID server's signatures verification to common

* Allow verification without specifying a server name

* Add third-party structs to membership events content

* Add processing of 3PID onbind requests

* Use reference for third party invite data

* Fix return arguments order

* Revert "Move the ID server's signatures verification to common"

This reverts commit 93442010316ce71a77ac58ffd3613754ce8fe969.

* Revert "Allow verification without specifying a server name"

This reverts commit fd27afbf82eac50fe9f7b83b26cfce3c66d530d2.

* Remove checks that are already occurring in gomatrixserverlib

* Change return type of createInviteFrom3PIDInvite

* Add doc, add checks in fillDisplayName

* Use MakeFedAPI

* Invert condition

* Use AuthEvents to retrieve the 3PID invite

* Update comment

* Remove unused parameter

* gb vendor update github.com/matrix-org/gomatrixserverlib

5 files changed, 245 insertions, 5 deletions

diff --git a/src/github.com/matrix-org/dendrite/common/eventcontent.go b/src/github.com/matrix-org/dendrite/common/eventcontent.go
index 0dfb37a1..971c4f0a 100644
--- a/src/github.com/matrix-org/dendrite/common/eventcontent.go
+++ b/src/github.com/matrix-org/dendrite/common/eventcontent.go
@@ -22,11 +22,24 @@ type CreateContent struct {
 
 // MemberContent is the event content for http://matrix.org/docs/spec/client_server/r0.2.0.html#m-room-member
 type MemberContent struct {
-	Membership  string `json:"membership"`
-	DisplayName string `json:"displayname,omitempty"`
-	AvatarURL   string `json:"avatar_url,omitempty"`
-	Reason      string `json:"reason,omitempty"`
-	// TODO: ThirdPartyInvite string `json:"third_party_invite,omitempty"`
+	Membership       string    `json:"membership"`
+	DisplayName      string    `json:"displayname,omitempty"`
+	AvatarURL        string    `json:"avatar_url,omitempty"`
+	Reason           string    `json:"reason,omitempty"`
+	ThirdPartyInvite *TPInvite `json:"third_party_invite,omitempty"`
+}
+
+// TPInvite is the "Invite" structure defined at http://matrix.org/docs/spec/client_server/r0.2.0.html#m-room-member
+type TPInvite struct {
+	DisplayName string         `json:"display_name"`
+	Signed      TPInviteSigned `json:"signed"`
+}
+
+// TPInviteSigned is the "signed" structure defined at http://matrix.org/docs/spec/client_server/r0.2.0.html#m-room-member
+type TPInviteSigned struct {
+	MXID       string                       `json:"mxid"`
+	Signatures map[string]map[string]string `json:"signatures"`
+	Token      string                       `json:"token"`
 }
 
 // ThirdPartyInviteContent is the content event for https://matrix.org/docs/spec/client_server/r0.2.0.html#m-room-third-party-invite
diff --git a/src/github.com/matrix-org/dendrite/federationapi/routing/routing.go b/src/github.com/matrix-org/dendrite/federationapi/routing/routing.go
index b4d01dab..8d49800d 100644
--- a/src/github.com/matrix-org/dendrite/federationapi/routing/routing.go
+++ b/src/github.com/matrix-org/dendrite/federationapi/routing/routing.go
@@ -79,6 +79,13 @@ func Setup(
 		},
 	))
 
+	v1fedmux.Handle("/3pid/onbind", common.MakeFedAPI(
+		"3pid_onbind", cfg.Matrix.ServerName, keys,
+		func(httpReq *http.Request, request *gomatrixserverlib.FederationRequest) util.JSONResponse {
+			return writers.CreateInvitesFrom3PIDInvites(httpReq, query, cfg, producer)
+		},
+	))
+
 	v1fedmux.Handle("/event/{eventID}", common.MakeFedAPI(
 		"federation_get_event", cfg.Matrix.ServerName, keys,
 		func(httpReq *http.Request, request *gomatrixserverlib.FederationRequest) util.JSONResponse {
diff --git a/src/github.com/matrix-org/dendrite/federationapi/writers/invite.go b/src/github.com/matrix-org/dendrite/federationapi/writers/invite.go
index 03972d36..20048103 100644
--- a/src/github.com/matrix-org/dendrite/federationapi/writers/invite.go
+++ b/src/github.com/matrix-org/dendrite/federationapi/writers/invite.go
@@ -1,3 +1,17 @@
+// Copyright 2017 Vector Creations Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package writers
 
 import (
diff --git a/src/github.com/matrix-org/dendrite/federationapi/writers/send.go b/src/github.com/matrix-org/dendrite/federationapi/writers/send.go
index f253162b..cd276f52 100644
--- a/src/github.com/matrix-org/dendrite/federationapi/writers/send.go
+++ b/src/github.com/matrix-org/dendrite/federationapi/writers/send.go
@@ -1,3 +1,17 @@
+// Copyright 2017 Vector Creations Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 package writers
 
 import (
diff --git a/src/github.com/matrix-org/dendrite/federationapi/writers/threepid.go b/src/github.com/matrix-org/dendrite/federationapi/writers/threepid.go
new file mode 100644
index 00000000..ad9b4856
--- /dev/null
+++ b/src/github.com/matrix-org/dendrite/federationapi/writers/threepid.go
@@ -0,0 +1,192 @@
+// Copyright 2017 Vector Creations Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package writers
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"time"
+
+	"github.com/matrix-org/dendrite/clientapi/httputil"
+	"github.com/matrix-org/dendrite/clientapi/producers"
+	"github.com/matrix-org/dendrite/common"
+	"github.com/matrix-org/dendrite/common/config"
+	"github.com/matrix-org/dendrite/roomserver/api"
+
+	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/matrix-org/util"
+)
+
+type invite struct {
+	MXID   string                `json:"mxid"`
+	RoomID string                `json:"room_id"`
+	Sender string                `json:"sender"`
+	Token  string                `json:"token"`
+	Signed common.TPInviteSigned `json:"signed"`
+}
+
+type invites struct {
+	Medium  string   `json:"medium"`
+	Address string   `json:"address"`
+	MXID    string   `json:"mxid"`
+	Invites []invite `json:"invites"`
+}
+
+// CreateInvitesFrom3PIDInvites implements POST /_matrix/federation/v1/3pid/onbind
+func CreateInvitesFrom3PIDInvites(
+	req *http.Request, queryAPI api.RoomserverQueryAPI, cfg config.Dendrite,
+	producer *producers.RoomserverProducer,
+) util.JSONResponse {
+	var body invites
+	if reqErr := httputil.UnmarshalJSONRequest(req, &body); reqErr != nil {
+		return *reqErr
+	}
+
+	evs := []gomatrixserverlib.Event{}
+	for _, inv := range body.Invites {
+		event, err := createInviteFrom3PIDInvite(queryAPI, cfg, inv)
+		if err != nil {
+			return httputil.LogThenError(req, err)
+		}
+		if event != nil {
+			evs = append(evs, *event)
+		}
+	}
+
+	// Send all the events
+	if err := producer.SendEvents(evs, cfg.Matrix.ServerName); err != nil {
+		return httputil.LogThenError(req, err)
+	}
+
+	return util.JSONResponse{
+		Code: 200,
+		JSON: struct{}{},
+	}
+}
+
+// createInviteFrom3PIDInvite processes an invite provided by the identity server
+// and creates a m.room.member event (with "invite" membership) from it.
+// Returns an error if there was a problem building the event or fetching the
+// necessary data to do so.
+func createInviteFrom3PIDInvite(
+	queryAPI api.RoomserverQueryAPI, cfg config.Dendrite, inv invite,
+) (*gomatrixserverlib.Event, error) {
+	// Build the event
+	builder := &gomatrixserverlib.EventBuilder{
+		Type:     "m.room.member",
+		Sender:   inv.Sender,
+		RoomID:   inv.RoomID,
+		StateKey: &inv.MXID,
+	}
+
+	content := common.MemberContent{
+		// TODO: Load the profile
+		Membership: "invite",
+		ThirdPartyInvite: &common.TPInvite{
+			Signed: inv.Signed,
+		},
+	}
+
+	if err := builder.SetContent(content); err != nil {
+		return nil, err
+	}
+
+	eventsNeeded, err := gomatrixserverlib.StateNeededForEventBuilder(builder)
+	if err != nil {
+		return nil, err
+	}
+
+	// Ask the roomserver for information about this room
+	queryReq := api.QueryLatestEventsAndStateRequest{
+		RoomID:       builder.RoomID,
+		StateToFetch: eventsNeeded.Tuples(),
+	}
+	var queryRes api.QueryLatestEventsAndStateResponse
+	if err = queryAPI.QueryLatestEventsAndState(&queryReq, &queryRes); err != nil {
+		return nil, err
+	}
+
+	if !queryRes.RoomExists {
+		// TODO: Use federation to auth the event
+		return nil, nil
+	}
+
+	// Finish building the event
+	builder.Depth = queryRes.Depth
+	builder.PrevEvents = queryRes.LatestEvents
+
+	authEvents := gomatrixserverlib.NewAuthEvents(nil)
+
+	for i := range queryRes.StateEvents {
+		authEvents.AddEvent(&queryRes.StateEvents[i])
+	}
+
+	if err = fillDisplayName(builder, content, authEvents); err != nil {
+		return nil, err
+	}
+
+	refs, err := eventsNeeded.AuthEventReferences(&authEvents)
+	if err != nil {
+		return nil, err
+	}
+	builder.AuthEvents = refs
+
+	eventID := fmt.Sprintf("$%s:%s", util.RandomString(16), cfg.Matrix.ServerName)
+	now := time.Now()
+	event, err := builder.Build(eventID, now, cfg.Matrix.ServerName, cfg.Matrix.KeyID, cfg.Matrix.PrivateKey)
+	if err != nil {
+		return nil, err
+	}
+
+	return &event, nil
+}
+
+// fillDisplayName looks in a list of auth events for a m.room.third_party_invite
+// event with the state key matching a given m.room.member event's content's token.
+// If such an event is found, fills the "display_name" attribute of the
+// "third_party_invite" structure in the m.room.member event with the display_name
+// from the m.room.third_party_invite event.
+// Returns an error if there was a problem parsing the m.room.third_party_invite
+// event's content or updating the m.room.member event's content.
+// Returns nil if no m.room.third_party_invite with a matching token could be
+// found. Returning an error isn't necessary in this case as the event will be
+// rejected by gomatrixserverlib.
+func fillDisplayName(
+	builder *gomatrixserverlib.EventBuilder, content common.MemberContent,
+	authEvents gomatrixserverlib.AuthEvents,
+) error {
+	// Look for the m.room.third_party_invite event
+	thirdPartyInviteEvent, _ := authEvents.ThirdPartyInvite(content.ThirdPartyInvite.Signed.Token)
+
+	if thirdPartyInviteEvent == nil {
+		// If the third party invite event doesn't exist then we can't use it to set the display name.
+		return nil
+	}
+
+	var thirdPartyInviteContent common.ThirdPartyInviteContent
+	if err := json.Unmarshal(thirdPartyInviteEvent.Content(), &thirdPartyInviteContent); err != nil {
+		return err
+	}
+
+	// Use the m.room.third_party_invite event to fill the "displayname" and
+	// update the m.room.member event's content with it
+	content.ThirdPartyInvite.DisplayName = thirdPartyInviteContent.DisplayName
+	if err := builder.SetContent(content); err != nil {
+		return err
+	}
+
+	return nil
+}