writefreely/activitypub.go

706 lines
18 KiB
Go

/*
* Copyright © 2018-2019 A Bunch Tell LLC.
*
* This file is part of WriteFreely.
*
* WriteFreely is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, included
* in the LICENSE file in this source code package.
*/
package writefreely
import (
"bytes"
"crypto/sha256"
"database/sql"
"encoding/base64"
"encoding/json"
"fmt"
"io/ioutil"
"net/http"
"net/http/httputil"
"net/url"
"strconv"
"time"
"github.com/gorilla/mux"
"github.com/writeas/activity/streams"
"github.com/writeas/httpsig"
"github.com/writeas/impart"
"github.com/writeas/nerds/store"
"github.com/writeas/web-core/activitypub"
"github.com/writeas/web-core/activitystreams"
"github.com/writeas/web-core/log"
)
const (
// TODO: delete. don't use this!
apCustomHandleDefault = "blog"
)
type RemoteUser struct {
ID int64
ActorID string
Inbox string
SharedInbox string
}
func (ru *RemoteUser) AsPerson() *activitystreams.Person {
return &activitystreams.Person{
BaseObject: activitystreams.BaseObject{
Type: "Person",
Context: []interface{}{
activitystreams.Namespace,
},
ID: ru.ActorID,
},
Inbox: ru.Inbox,
Endpoints: activitystreams.Endpoints{
SharedInbox: ru.SharedInbox,
},
}
}
func handleFetchCollectionActivities(app *App, w http.ResponseWriter, r *http.Request) error {
w.Header().Set("Server", serverSoftware)
vars := mux.Vars(r)
alias := vars["alias"]
// TODO: enforce visibility
// Get base Collection data
var c *Collection
var err error
if app.cfg.App.SingleUser {
c, err = app.db.GetCollectionByID(1)
} else {
c, err = app.db.GetCollection(alias)
}
if err != nil {
return err
}
c.hostName = app.cfg.App.Host
p := c.PersonObject()
return impart.RenderActivityJSON(w, p, http.StatusOK)
}
func handleFetchCollectionOutbox(app *App, w http.ResponseWriter, r *http.Request) error {
w.Header().Set("Server", serverSoftware)
vars := mux.Vars(r)
alias := vars["alias"]
// TODO: enforce visibility
// Get base Collection data
var c *Collection
var err error
if app.cfg.App.SingleUser {
c, err = app.db.GetCollectionByID(1)
} else {
c, err = app.db.GetCollection(alias)
}
if err != nil {
return err
}
c.hostName = app.cfg.App.Host
if app.cfg.App.SingleUser {
if alias != c.Alias {
return ErrCollectionNotFound
}
}
res := &CollectionObj{Collection: *c}
app.db.GetPostsCount(res, false)
accountRoot := c.FederatedAccount()
page := r.FormValue("page")
p, err := strconv.Atoi(page)
if err != nil || p < 1 {
// Return outbox
oc := activitystreams.NewOrderedCollection(accountRoot, "outbox", res.TotalPosts)
return impart.RenderActivityJSON(w, oc, http.StatusOK)
}
// Return outbox page
ocp := activitystreams.NewOrderedCollectionPage(accountRoot, "outbox", res.TotalPosts, p)
ocp.OrderedItems = []interface{}{}
posts, err := app.db.GetPosts(app.cfg, c, p, false, true, false)
for _, pp := range *posts {
pp.Collection = res
o := pp.ActivityObject(app.cfg)
a := activitystreams.NewCreateActivity(o)
ocp.OrderedItems = append(ocp.OrderedItems, *a)
}
return impart.RenderActivityJSON(w, ocp, http.StatusOK)
}
func handleFetchCollectionFollowers(app *App, w http.ResponseWriter, r *http.Request) error {
w.Header().Set("Server", serverSoftware)
vars := mux.Vars(r)
alias := vars["alias"]
// TODO: enforce visibility
// Get base Collection data
var c *Collection
var err error
if app.cfg.App.SingleUser {
c, err = app.db.GetCollectionByID(1)
} else {
c, err = app.db.GetCollection(alias)
}
if err != nil {
return err
}
c.hostName = app.cfg.App.Host
accountRoot := c.FederatedAccount()
folls, err := app.db.GetAPFollowers(c)
if err != nil {
return err
}
page := r.FormValue("page")
p, err := strconv.Atoi(page)
if err != nil || p < 1 {
// Return outbox
oc := activitystreams.NewOrderedCollection(accountRoot, "followers", len(*folls))
return impart.RenderActivityJSON(w, oc, http.StatusOK)
}
// Return outbox page
ocp := activitystreams.NewOrderedCollectionPage(accountRoot, "followers", len(*folls), p)
ocp.OrderedItems = []interface{}{}
/*
for _, f := range *folls {
ocp.OrderedItems = append(ocp.OrderedItems, f.ActorID)
}
*/
return impart.RenderActivityJSON(w, ocp, http.StatusOK)
}
func handleFetchCollectionFollowing(app *App, w http.ResponseWriter, r *http.Request) error {
w.Header().Set("Server", serverSoftware)
vars := mux.Vars(r)
alias := vars["alias"]
// TODO: enforce visibility
// Get base Collection data
var c *Collection
var err error
if app.cfg.App.SingleUser {
c, err = app.db.GetCollectionByID(1)
} else {
c, err = app.db.GetCollection(alias)
}
if err != nil {
return err
}
c.hostName = app.cfg.App.Host
accountRoot := c.FederatedAccount()
page := r.FormValue("page")
p, err := strconv.Atoi(page)
if err != nil || p < 1 {
// Return outbox
oc := activitystreams.NewOrderedCollection(accountRoot, "following", 0)
return impart.RenderActivityJSON(w, oc, http.StatusOK)
}
// Return outbox page
ocp := activitystreams.NewOrderedCollectionPage(accountRoot, "following", 0, p)
ocp.OrderedItems = []interface{}{}
return impart.RenderActivityJSON(w, ocp, http.StatusOK)
}
func handleFetchCollectionInbox(app *App, w http.ResponseWriter, r *http.Request) error {
w.Header().Set("Server", serverSoftware)
vars := mux.Vars(r)
alias := vars["alias"]
var c *Collection
var err error
if app.cfg.App.SingleUser {
c, err = app.db.GetCollectionByID(1)
} else {
c, err = app.db.GetCollection(alias)
}
if err != nil {
// TODO: return Reject?
return err
}
c.hostName = app.cfg.App.Host
if debugging {
dump, err := httputil.DumpRequest(r, true)
if err != nil {
log.Error("Can't dump: %v", err)
} else {
log.Info("Rec'd! %q", dump)
}
}
var m map[string]interface{}
if err := json.NewDecoder(r.Body).Decode(&m); err != nil {
return err
}
a := streams.NewAccept()
p := c.PersonObject()
var to *url.URL
var isFollow, isUnfollow bool
fullActor := &activitystreams.Person{}
var remoteUser *RemoteUser
res := &streams.Resolver{
FollowCallback: func(f *streams.Follow) error {
isFollow = true
// 1) Use the Follow concrete type here
// 2) Errors are propagated to res.Deserialize call below
m["@context"] = []string{activitystreams.Namespace}
b, _ := json.Marshal(m)
if debugging {
log.Info("Follow: %s", b)
}
_, followID := f.GetId()
if followID == nil {
log.Error("Didn't resolve follow ID")
} else {
aID := c.FederatedAccount() + "#accept-" + store.GenerateFriendlyRandomString(20)
acceptID, err := url.Parse(aID)
if err != nil {
log.Error("Couldn't parse generated Accept URL '%s': %v", aID, err)
}
a.SetId(acceptID)
}
a.AppendObject(f.Raw())
_, to = f.GetActor(0)
obj := f.Raw().GetObjectIRI(0)
a.AppendActor(obj)
// First get actor information
if to == nil {
return fmt.Errorf("No valid `to` string")
}
fullActor, remoteUser, err = getActor(app, to.String())
if err != nil {
return err
}
return impart.RenderActivityJSON(w, m, http.StatusOK)
},
UndoCallback: func(u *streams.Undo) error {
isUnfollow = true
m["@context"] = []string{activitystreams.Namespace}
b, _ := json.Marshal(m)
if debugging {
log.Info("Undo: %s", b)
}
a.AppendObject(u.Raw())
_, to = u.GetActor(0)
// TODO: get actor from object.object, not object
obj := u.Raw().GetObjectIRI(0)
a.AppendActor(obj)
if to != nil {
// Populate fullActor from DB?
remoteUser, err = getRemoteUser(app, to.String())
if err != nil {
if iErr, ok := err.(*impart.HTTPError); ok {
if iErr.Status == http.StatusNotFound {
log.Error("No remoteuser info for Undo event!")
}
}
return err
} else {
fullActor = remoteUser.AsPerson()
}
} else {
log.Error("No to on Undo!")
}
return impart.RenderActivityJSON(w, m, http.StatusOK)
},
}
if err := res.Deserialize(m); err != nil {
// 3) Any errors from #2 can be handled, or the payload is an unknown type.
log.Error("Unable to resolve Follow: %v", err)
if debugging {
log.Error("Map: %s", m)
}
return err
}
go func() {
time.Sleep(2 * time.Second)
am, err := a.Serialize()
if err != nil {
log.Error("Unable to serialize Accept: %v", err)
return
}
am["@context"] = []string{activitystreams.Namespace}
if to == nil {
log.Error("No to! %v", err)
return
}
err = makeActivityPost(app.cfg.App.Host, p, fullActor.Inbox, am)
if err != nil {
log.Error("Unable to make activity POST: %v", err)
return
}
if isFollow {
t, err := app.db.Begin()
if err != nil {
log.Error("Unable to start transaction: %v", err)
return
}
var followerID int64
if remoteUser != nil {
followerID = remoteUser.ID
} else {
// Add follower locally, since it wasn't found before
res, err := t.Exec("INSERT INTO remoteusers (actor_id, inbox, shared_inbox) VALUES (?, ?, ?)", fullActor.ID, fullActor.Inbox, fullActor.Endpoints.SharedInbox)
if err != nil {
if !app.db.isDuplicateKeyErr(err) {
t.Rollback()
log.Error("Couldn't add new remoteuser in DB: %v\n", err)
return
}
}
followerID, err = res.LastInsertId()
if err != nil {
t.Rollback()
log.Error("no lastinsertid for followers, rolling back: %v", err)
return
}
// Add in key
_, err = t.Exec("INSERT INTO remoteuserkeys (id, remote_user_id, public_key) VALUES (?, ?, ?)", fullActor.PublicKey.ID, followerID, fullActor.PublicKey.PublicKeyPEM)
if err != nil {
if !app.db.isDuplicateKeyErr(err) {
t.Rollback()
log.Error("Couldn't add follower keys in DB: %v\n", err)
return
}
}
}
// Add follow
_, err = t.Exec("INSERT INTO remotefollows (collection_id, remote_user_id, created) VALUES (?, ?, "+app.db.now()+")", c.ID, followerID)
if err != nil {
if !app.db.isDuplicateKeyErr(err) {
t.Rollback()
log.Error("Couldn't add follower in DB: %v\n", err)
return
}
}
err = t.Commit()
if err != nil {
t.Rollback()
log.Error("Rolling back after Commit(): %v\n", err)
return
}
} else if isUnfollow {
// Remove follower locally
_, err = app.db.Exec("DELETE FROM remotefollows WHERE collection_id = ? AND remote_user_id = (SELECT id FROM remoteusers WHERE actor_id = ?)", c.ID, to.String())
if err != nil {
log.Error("Couldn't remove follower from DB: %v\n", err)
}
}
}()
return nil
}
func makeActivityPost(hostName string, p *activitystreams.Person, url string, m interface{}) error {
log.Info("POST %s", url)
b, err := json.Marshal(m)
if err != nil {
return err
}
r, _ := http.NewRequest("POST", url, bytes.NewBuffer(b))
r.Header.Add("Content-Type", "application/activity+json")
r.Header.Set("User-Agent", "Go ("+serverSoftware+"/"+softwareVer+"; +"+hostName+")")
h := sha256.New()
h.Write(b)
r.Header.Add("Digest", "SHA-256="+base64.StdEncoding.EncodeToString(h.Sum(nil)))
// Sign using the 'Signature' header
privKey, err := activitypub.DecodePrivateKey(p.GetPrivKey())
if err != nil {
return err
}
signer := httpsig.NewSigner(p.PublicKey.ID, privKey, httpsig.RSASHA256, []string{"(request-target)", "date", "host", "digest"})
err = signer.SignSigHeader(r)
if err != nil {
log.Error("Can't sign: %v", err)
}
if debugging {
dump, err := httputil.DumpRequestOut(r, true)
if err != nil {
log.Error("Can't dump: %v", err)
} else {
log.Info("%s", dump)
}
}
resp, err := http.DefaultClient.Do(r)
if err != nil {
return err
}
if resp != nil && resp.Body != nil {
defer resp.Body.Close()
}
body, err := ioutil.ReadAll(resp.Body)
if err != nil {
return err
}
if debugging {
log.Info("Status : %s", resp.Status)
log.Info("Response: %s", body)
}
return nil
}
func resolveIRI(hostName, url string) ([]byte, error) {
log.Info("GET %s", url)
r, _ := http.NewRequest("GET", url, nil)
r.Header.Add("Accept", "application/activity+json")
r.Header.Set("User-Agent", "Go ("+serverSoftware+"/"+softwareVer+"; +"+hostName+")")
if debugging {
dump, err := httputil.DumpRequestOut(r, true)
if err != nil {
log.Error("Can't dump: %v", err)
} else {
log.Info("%s", dump)
}
}
resp, err := http.DefaultClient.Do(r)
if err != nil {
return nil, err
}
if resp != nil && resp.Body != nil {
defer resp.Body.Close()
}
body, err := ioutil.ReadAll(resp.Body)
if err != nil {
return nil, err
}
if debugging {
log.Info("Status : %s", resp.Status)
log.Info("Response: %s", body)
}
return body, nil
}
func deleteFederatedPost(app *App, p *PublicPost, collID int64) error {
if debugging {
log.Info("Deleting federated post!")
}
p.Collection.hostName = app.cfg.App.Host
actor := p.Collection.PersonObject(collID)
na := p.ActivityObject(app.cfg)
// Add followers
p.Collection.ID = collID
followers, err := app.db.GetAPFollowers(&p.Collection.Collection)
if err != nil {
log.Error("Couldn't delete post (get followers)! %v", err)
return err
}
inboxes := map[string][]string{}
for _, f := range *followers {
inbox := f.SharedInbox
if inbox == "" {
inbox = f.Inbox
}
if _, ok := inboxes[inbox]; ok {
inboxes[inbox] = append(inboxes[inbox], f.ActorID)
} else {
inboxes[inbox] = []string{f.ActorID}
}
}
for si, instFolls := range inboxes {
na.CC = []string{}
for _, f := range instFolls {
na.CC = append(na.CC, f)
}
err = makeActivityPost(app.cfg.App.Host, actor, si, activitystreams.NewDeleteActivity(na))
if err != nil {
log.Error("Couldn't delete post! %v", err)
}
}
return nil
}
func federatePost(app *App, p *PublicPost, collID int64, isUpdate bool) error {
if debugging {
if isUpdate {
log.Info("Federating updated post!")
} else {
log.Info("Federating new post!")
}
}
actor := p.Collection.PersonObject(collID)
na := p.ActivityObject(app.cfg)
// Add followers
p.Collection.ID = collID
followers, err := app.db.GetAPFollowers(&p.Collection.Collection)
if err != nil {
log.Error("Couldn't post! %v", err)
return err
}
log.Info("Followers for %d: %+v", collID, followers)
inboxes := map[string][]string{}
for _, f := range *followers {
inbox := f.SharedInbox
if inbox == "" {
inbox = f.Inbox
}
if _, ok := inboxes[inbox]; ok {
inboxes[inbox] = append(inboxes[inbox], f.ActorID)
} else {
inboxes[inbox] = []string{f.ActorID}
}
}
for si, instFolls := range inboxes {
na.CC = []string{}
for _, f := range instFolls {
na.CC = append(na.CC, f)
}
var activity *activitystreams.Activity
if isUpdate {
activity = activitystreams.NewUpdateActivity(na)
} else {
activity = activitystreams.NewCreateActivity(na)
activity.To = na.To
activity.CC = na.CC
}
err = makeActivityPost(app.cfg.App.Host, actor, si, activity)
if err != nil {
log.Error("Couldn't post! %v", err)
}
}
return nil
}
func getRemoteUser(app *App, actorID string) (*RemoteUser, error) {
u := RemoteUser{ActorID: actorID}
err := app.db.QueryRow("SELECT id, inbox, shared_inbox FROM remoteusers WHERE actor_id = ?", actorID).Scan(&u.ID, &u.Inbox, &u.SharedInbox)
switch {
case err == sql.ErrNoRows:
return nil, impart.HTTPError{http.StatusNotFound, "No remote user with that ID."}
case err != nil:
log.Error("Couldn't get remote user %s: %v", actorID, err)
return nil, err
}
return &u, nil
}
func getActor(app *App, actorIRI string) (*activitystreams.Person, *RemoteUser, error) {
log.Info("Fetching actor %s locally", actorIRI)
actor := &activitystreams.Person{}
remoteUser, err := getRemoteUser(app, actorIRI)
if err != nil {
if iErr, ok := err.(impart.HTTPError); ok {
if iErr.Status == http.StatusNotFound {
// Fetch remote actor
log.Info("Not found; fetching actor %s remotely", actorIRI)
actorResp, err := resolveIRI(app.cfg.App.Host, actorIRI)
if err != nil {
log.Error("Unable to get actor! %v", err)
return nil, nil, impart.HTTPError{http.StatusInternalServerError, "Couldn't fetch actor."}
}
if err := unmarshalActor(actorResp, actor); err != nil {
log.Error("Unable to unmarshal actor! %v", err)
return nil, nil, impart.HTTPError{http.StatusInternalServerError, "Couldn't parse actor."}
}
} else {
return nil, nil, err
}
} else {
return nil, nil, err
}
} else {
actor = remoteUser.AsPerson()
}
return actor, remoteUser, nil
}
// unmarshal actor normalizes the actor response to conform to
// the type Person from github.com/writeas/web-core/activitysteams
//
// some implementations return different context field types
// this converts any non-slice contexts into a slice
func unmarshalActor(actorResp []byte, actor *activitystreams.Person) error {
// FIXME: Hubzilla has an object for the Actor's url: cannot unmarshal object into Go struct field Person.url of type string
// flexActor overrides the Context field to allow
// all valid representations during unmarshal
flexActor := struct {
activitystreams.Person
Context json.RawMessage `json:"@context,omitempty"`
}{}
if err := json.Unmarshal(actorResp, &flexActor); err != nil {
return err
}
actor.Endpoints = flexActor.Endpoints
actor.Followers = flexActor.Followers
actor.Following = flexActor.Following
actor.ID = flexActor.ID
actor.Icon = flexActor.Icon
actor.Inbox = flexActor.Inbox
actor.Name = flexActor.Name
actor.Outbox = flexActor.Outbox
actor.PreferredUsername = flexActor.PreferredUsername
actor.PublicKey = flexActor.PublicKey
actor.Summary = flexActor.Summary
actor.Type = flexActor.Type
actor.URL = flexActor.URL
func(val interface{}) {
switch val.(type) {
case []interface{}:
// already a slice, do nothing
actor.Context = val.([]interface{})
default:
actor.Context = []interface{}{val}
}
}(flexActor.Context)
return nil
}