func namelessTimeout(id uint64) {
store.StartTransaction()
defer store.EndTransaction()
// If the timeout has been removed, do nothing.
if namelessRemoveTimeouts[id] == nil {
return
}
// Remove nameless user.
// TODO: Should make sure we only do this once.
user := store.GetEntity(id)
if user != nil {
chset := make([]store.Change, 1)
chset[0].TargetEntity = id
chset[0].Key = "id"
chset[0].Value = ""
req := makeRequest(chset)
go chrequest.Request(req)
}
}
func orphanTimeout(id uint64) {
store.StartTransaction()
defer store.EndTransaction()
// If the timeout has been removed, do nothing.
if namelessRemoveTimeouts[id] == nil {
return
}
// Detach ourselves from the session.
// TODO: Should make sure we only do this once.
ourAttachStr := "attach " + strconv.FormatUint(uint64(config.Id()), 10)
session := store.GetEntity(id)
if session != nil {
chset := make([]store.Change, 1)
chset[0].TargetEntity = id
chset[0].Key = ourAttachStr
chset[0].Value = ""
req := makeRequest(chset)
go chrequest.Request(req)
}
}
// Main function for the handling goroutine for conn.
func handleConn(conn *userConn) {
// Do cleanup in a defer, so if they crash us we still tidy up here.
// A small nod towards tolerating bad input, with much more needed.
defer func() {
// Remove the connection from our connection set if present.
// It will not be present if we are degraded or similar.
connectionsLock.Lock()
if _, exists := connections[conn]; exists {
delete(connections, conn)
}
// Remove the connection from our waiting map if present.
// This must happen before session removal, as otherwise
// auth could complete between the session check and this one.
waitingLock.Lock()
if conn.waitingAuth != nil {
waitingConn := waiting[conn.waitingAuth.requestId]
if waitingConn == conn {
delete(waiting, conn.waitingAuth.requestId)
}
}
waitingLock.Unlock()
// Remove the connection from our sessions map if present.
// It will not be present if we are degraded,
// or have replaced this connection.
sessionsLock.Lock()
if conn.session != 0 {
sessionConn := sessions[conn.session]
if sessionConn == conn {
delete(sessions, conn.session)
// Send a change detaching this node
// from that session.
idStr := strconv.FormatUint(uint64(config.Id()),
10)
ourAttachStr := "attach " + idStr
chset := make([]store.Change, 1)
chset[0].TargetEntity = conn.session
chset[0].Key = ourAttachStr
chset[0].Value = ""
req := makeRequest(chset)
go chrequest.Request(req)
}
}
sessionsLock.Unlock()
connectionsLock.Unlock()
}()
for {
select {
case msg, ok := <-conn.conn.Received:
if !ok {
return
}
switch *msg.MsgType {
case 2:
handleAuth(conn, msg.Content)
case 3:
handleFollowUsername(conn, msg.Content)
case 4:
handleFollowUser(conn, msg.Content)
case 5:
handleStopFollowingUser(conn, msg.Content)
case 6:
handleSend(conn, msg.Content)
default:
conn.conn.Close()
}
case userMsg := <-conn.deliver:
// Get the sender's user ID.
store.StartTransaction()
attachedTo := store.AllAttachedTo(userMsg.Sender)
store.EndTransaction()
// We don't know who the sender is. Drop message.
if len(attachedTo) == 0 {
break
}
// Deliver any user messages given to us.
var deliverMsg cliproto_down.Received
deliverMsg.SenderUserId = new(uint64)
deliverMsg.SenderSessionId = new(uint64)
deliverMsg.Tag = new(string)
deliverMsg.Content = new(string)
*deliverMsg.SenderUserId = attachedTo[0]
*deliverMsg.SenderSessionId = userMsg.Sender
*deliverMsg.Tag = userMsg.Tag
*deliverMsg.Content = userMsg.Content
conn.conn.SendProto(10, &deliverMsg)
}
}
}
// Can only be called from the handling goroutine for conn.
func handleAuth(conn *userConn, content []byte) {
var msg cliproto_up.Authenticate
if err := proto.Unmarshal(content, &msg); err != nil {
conn.conn.Close()
return
}
// Try to get information, then release locks and hash the password.
// If the situation changes we may have to hash it again anyway,
// but scrypt hashing is extremely expensive and we want to try to
// do this without holding our locks in the vast majority of cases.
var tryPassGenerated bool
var trySaltGenerated bool
var tryPass, trySalt, tryKey string
if *msg.Password != "" {
tryPass = *msg.Password
store.StartTransaction()
userId := store.NameLookup("user", "name username",
*msg.Username)
if userId != 0 {
user := store.GetEntity(userId)
if user != nil {
trySalt = user.Value("auth salt")
}
}
store.EndTransaction()
if trySalt == "" {
trySaltGenerated = true
var err error
trySalt, tryKey, err = genRandomSalt(conn,
[]byte(tryPass))
if err != nil {
return
}
} else {
var err error
tryPass, err = genKey(conn, []byte(tryPass),
[]byte(trySalt))
if err != nil {
return
}
}
} else {
tryPassGenerated = true
trySaltGenerated = true
var err error
tryPass, trySalt, tryKey, err = genRandomPass(conn)
if err != nil {
return
}
}
// TODO: Validate username and password against constraints.
// We hold this through quite a lot of logic.
// Would be good to be locked less.
store.StartTransaction()
defer store.EndTransaction()
sessionsLock.Lock()
defer sessionsLock.Unlock()
waitingLock.Lock()
defer waitingLock.Unlock()
if conn.session != 0 || conn.waitingAuth != nil {
conn.conn.Close()
return
}
userId := store.NameLookup("user", "name username", *msg.Username)
if userId != 0 {
if *msg.Password == "" {
sendAuthFail(conn, "Invalid Password")
return
}
// The user already exists.
user := store.GetEntity(userId)
// Try to authenticate them to it.
var key string
// If their salt and password matches our attempt above,
// we can just take that key.
salt := user.Value("auth salt")
if trySalt == salt && tryPass == *msg.Password {
key = tryKey
} else {
saltBytes := []byte(user.Value("auth salt"))
passBytes := []byte(*msg.Password)
var err error
key, err = genKey(conn, passBytes, saltBytes)
if err != nil {
return
}
}
if user.Value("auth password") != string(key) {
sendAuthFail(conn, "Invalid Password")
return
}
// It's the real user.
if *msg.SessionId != 0 {
// They are attaching to an existing session.
// Check it exists and is attached to this user.
strSessionId := strconv.FormatUint(*msg.SessionId, 10)
if user.Value("attach "+strSessionId) == "" {
sendAuthFail(conn, "Invalid Session")
return
}
// The session does exist.
conn.session = *msg.SessionId
// If this node is already attached to
// the session, drop the other connection.
if sessions[conn.session] != nil {
sessions[conn.session].conn.Close()
} else {
// Create change attaching this node ID
// to the session.
id := config.Id()
idStr := strconv.FormatUint(uint64(id), 10)
chset := make([]store.Change, 1)
chset[0].TargetEntity = conn.session
chset[0].Key = "attach " + idStr
chset[0].Value = "true"
req := makeRequest(chset)
go chrequest.Request(req)
}
// Put us in the sessions map.
sessions[conn.session] = conn
// Tell the client they authenticated successfully.
sendAuthSuccess(conn, "")
} else {
// They are creating a new session.
req := makeNewSessionRequest(userId)
go chrequest.Request(req)
// Stuff details in waiting auth.
conn.waitingAuth = new(authData)
conn.waitingAuth.msg = msg
conn.waitingAuth.requestId = req.RequestId
waiting[conn.waitingAuth.requestId] = conn
}
} else {
// The user does not already exist.
// Check they weren't trying to attach to a session.
if *msg.SessionId != 0 {
sendAuthFail(conn, "User Does Not Exist")
return
}
// We're creating a new user.
newUser := *msg.Username
newPass := *msg.Password
if !strings.HasPrefix(newUser, "Guest-") {
// We're creating a new non-guest user.
// Make sure they have a password.
if newPass == "" {
sendAuthFail(conn, "No Password")
return
}
var salt string
var hash string
if tryPass == newPass && trySaltGenerated {
salt = trySalt
hash = tryKey
} else {
passBytes := []byte(newPass)
var err error
salt, hash, err = genRandomSalt(conn, passBytes)
if err != nil {
return
}
}
// Create the new user.
req := makeNewUserRequest(newUser, hash, salt, false)
go chrequest.Request(req)
// Stuff details in waiting auth.
conn.waitingAuth = new(authData)
conn.waitingAuth.msg = msg
conn.waitingAuth.requestId = req.RequestId
waiting[conn.waitingAuth.requestId] = conn
return
}
// We're creating a new guest user.
// Guests get automatic passwords, and can't set them.
if newPass != "" {
sendAuthFail(conn, "Cannot Set Password For Guest User")
return
}
var hash string
var salt string
if tryPassGenerated && trySaltGenerated {
newPass = tryPass
salt = trySalt
hash = tryKey
} else {
var err error
newPass, salt, hash, err = genRandomPass(conn)
if err != nil {
return
}
}
waitingLock.Lock()
// Create the new user.
req := makeNewUserRequest(newUser, hash, salt, true)
go chrequest.Request(req)
// Stuff details in waiting auth.
conn.waitingAuth = new(authData)
conn.waitingAuth.msg = msg
conn.waitingAuth.requestId = req.RequestId
waiting[conn.waitingAuth.requestId] = conn
waitingLock.Unlock()
return
}
}