From 4113599f61690fd1fe660ad246f4e1c4c65b4865 Mon Sep 17 00:00:00 2001
From: Prateek Sachan <42961174+prateek2211@users.noreply.github.com>
Date: Thu, 30 Jan 2020 16:55:57 +0530
Subject: [PATCH] Handle kind=guest query parameter on /register (#860)

* Handle kind=guest query parameter on /register

* Reorganized imports

* Pass device_id as nil

* Added tests to systest-whitelist
---
 clientapi/routing/register.go | 57 +++++++++++++++++++++++++++++++++++
 go.mod                        |  2 ++
 sytest-whitelist              | 17 +++++++++++
 3 files changed, 76 insertions(+)

diff --git a/clientapi/routing/register.go b/clientapi/routing/register.go
index d0f36a6f..4e50e57b 100644
--- a/clientapi/routing/register.go
+++ b/clientapi/routing/register.go
@@ -43,6 +43,7 @@ import (
 	"github.com/matrix-org/dendrite/clientapi/userutil"
 	"github.com/matrix-org/dendrite/common"
 	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/matrix-org/gomatrixserverlib/tokens"
 	"github.com/matrix-org/util"
 	"github.com/prometheus/client_golang/prometheus"
 	log "github.com/sirupsen/logrus"
@@ -449,6 +450,9 @@ func Register(
 	if resErr != nil {
 		return *resErr
 	}
+	if req.URL.Query().Get("kind") == "guest" {
+		return handleGuestRegistration(req, r, cfg, accountDB, deviceDB)
+	}
 
 	// Retrieve or generate the sessionID
 	sessionID := r.Auth.Session
@@ -505,6 +509,59 @@ func Register(
 	return handleRegistrationFlow(req, r, sessionID, cfg, accountDB, deviceDB)
 }
 
+func handleGuestRegistration(
+	req *http.Request,
+	r registerRequest,
+	cfg *config.Dendrite,
+	accountDB *accounts.Database,
+	deviceDB *devices.Database,
+) util.JSONResponse {
+
+	//Generate numeric local part for guest user
+	id, err := accountDB.GetNewNumericLocalpart(req.Context())
+	if err != nil {
+		return httputil.LogThenError(req, err)
+	}
+
+	localpart := strconv.FormatInt(id, 10)
+	acc, err := accountDB.CreateAccount(req.Context(), localpart, "", "")
+	if err != nil {
+		return util.JSONResponse{
+			Code: http.StatusInternalServerError,
+			JSON: jsonerror.Unknown("failed to create account: " + err.Error()),
+		}
+	}
+	token, err := tokens.GenerateLoginToken(tokens.TokenOptions{
+		ServerPrivateKey: cfg.Matrix.PrivateKey.Seed(),
+		ServerName:       string(acc.ServerName),
+		UserID:           acc.UserID,
+	})
+
+	if err != nil {
+		return util.JSONResponse{
+			Code: http.StatusInternalServerError,
+			JSON: jsonerror.Unknown("Failed to generate access token"),
+		}
+	}
+	//we don't allow guests to specify their own device_id
+	dev, err := deviceDB.CreateDevice(req.Context(), acc.Localpart, nil, token, r.InitialDisplayName)
+	if err != nil {
+		return util.JSONResponse{
+			Code: http.StatusInternalServerError,
+			JSON: jsonerror.Unknown("failed to create device: " + err.Error()),
+		}
+	}
+	return util.JSONResponse{
+		Code: http.StatusOK,
+		JSON: registerResponse{
+			UserID:      dev.UserID,
+			AccessToken: dev.AccessToken,
+			HomeServer:  acc.ServerName,
+			DeviceID:    dev.ID,
+		},
+	}
+}
+
 // handleRegistrationFlow will direct and complete registration flow stages
 // that the client has requested.
 // nolint: gocyclo
diff --git a/go.mod b/go.mod
index 990b839e..4c894ad9 100644
--- a/go.mod
+++ b/go.mod
@@ -18,6 +18,8 @@ require (
 	github.com/matrix-org/naffka v0.0.0-20171115094957-662bfd0841d0
 	github.com/matrix-org/util v0.0.0-20171127121716-2e2df66af2f5
 	github.com/miekg/dns v1.1.12 // indirect
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
+	github.com/modern-go/reflect2 v1.0.1 // indirect
 	github.com/nfnt/resize v0.0.0-20160724205520-891127d8d1b5
 	github.com/opentracing/opentracing-go v1.0.2
 	github.com/pierrec/lz4 v0.0.0-20161206202305-5c9560bfa9ac // indirect
diff --git a/sytest-whitelist b/sytest-whitelist
index 4c333d3c..7b704f62 100644
--- a/sytest-whitelist
+++ b/sytest-whitelist
@@ -210,3 +210,20 @@ Message history can be paginated
 Getting messages going forward is limited for a departed room (SPEC-216)
 m.room.history_visibility == "world_readable" allows/forbids appropriately for Real users
 Backfill works correctly with history visibility set to joined
+Guest user cannot call /events globally
+Guest users can join guest_access rooms
+Guest user can set display names
+Guest user cannot upgrade other users
+m.room.history_visibility == "world_readable" allows/forbids appropriately for Guest users
+Guest non-joined user cannot call /events on shared room
+Guest non-joined user cannot call /events on invited room
+Guest non-joined user cannot call /events on joined room
+Guest non-joined user cannot call /events on default room
+Guest non-joined users can get state for world_readable rooms
+Guest non-joined users can get individual state for world_readable rooms
+Guest non-joined users cannot room initalSync for non-world_readable rooms
+Guest non-joined users can get individual state for world_readable rooms after leaving
+Guest non-joined users cannot send messages to guest_access rooms if not joined
+Guest users can sync from world_readable guest_access rooms if joined
+Guest users can sync from default guest_access rooms if joined
+Real non-joined users cannot room initalSync for non-world_readable rooms