owpengram-server/internal/mtprotoedge/rpc_rewrap.go

455 lines
12 KiB
Go

package mtprotoedge
import (
"context"
"crypto/sha256"
"sync"
"sync/atomic"
"time"
"go.uber.org/zap"
"github.com/gotd/td/bin"
"github.com/gotd/td/proto"
"github.com/gotd/td/tg"
)
// rpcRewrapRegistry links only an explicit official-client transition:
// outstanding naked request -> invokeWithLayer(initConnection(the exact same
// request)). It is not a general content-dedup cache. Entries are hard-bounded
// and are retired by protocol events (client ACK, alias consumption, owner
// abort, or the first post-init naked request), never by client identity or by
// delaying request execution.
type rpcRewrapRegistry struct {
mu sync.Mutex
max int
total int
byKey map[rpcRewrapKey][]*rpcRewrapCandidate
bySession map[rpcRewrapSessionKey]map[*rpcRewrapCandidate]struct{}
byRequest map[rpcRewrapRequestKey]*rpcRewrapCandidate
}
type rpcRewrapSessionKey struct {
authKeyID [8]byte
sessionID int64
}
type rpcRewrapKey struct {
rpcRewrapSessionKey
fingerprint [sha256.Size]byte
}
type rpcRewrapRequestKey struct {
rpcRewrapSessionKey
reqMsgID int64
}
type rpcRewrapCandidate struct {
active bool
claimed bool
key rpcRewrapKey
source *Conn
reqMsgID int64
method string
owner *rpcResultOwnerLease
waiter *rpcResultWaiter
}
func newRPCRewrapRegistry(max int) *rpcRewrapRegistry {
if max <= 0 {
max = rpcResultFlightDefaultMaxPending
}
return &rpcRewrapRegistry{
max: max,
byKey: make(map[rpcRewrapKey][]*rpcRewrapCandidate),
bySession: make(map[rpcRewrapSessionKey]map[*rpcRewrapCandidate]struct{}),
byRequest: make(map[rpcRewrapRequestKey]*rpcRewrapCandidate),
}
}
func (r *rpcRewrapRegistry) register(c *Conn, body []byte, reqMsgID int64, method string, owner *rpcResultOwnerLease) bool {
if r == nil || c == nil || c.rpcRewrapInitialized.Load() || owner == nil {
return false
}
session := rpcRewrapSessionKey{authKeyID: c.authKeyID, sessionID: c.sessionID}
key := rpcRewrapKey{rpcRewrapSessionKey: session, fingerprint: sha256.Sum256(body)}
candidate := &rpcRewrapCandidate{
active: true, key: key, source: c, reqMsgID: reqMsgID, method: method,
owner: owner, waiter: owner.Waiter(),
}
if candidate.waiter == nil {
return false
}
r.mu.Lock()
if r.total >= r.max {
r.mu.Unlock()
return false
}
r.byKey[key] = append(r.byKey[key], candidate)
set := r.bySession[session]
if set == nil {
set = make(map[*rpcRewrapCandidate]struct{})
r.bySession[session] = set
}
set[candidate] = struct{}{}
r.byRequest[rpcRewrapRequestKey{rpcRewrapSessionKey: session, reqMsgID: reqMsgID}] = candidate
r.total++
r.mu.Unlock()
if !owner.InstallAbortHook(func() { r.remove(candidate) }) {
r.remove(candidate)
return false
}
return true
}
func (r *rpcRewrapRegistry) claim(c *Conn, inner []byte) *rpcRewrapCandidate {
if r == nil || c == nil {
return nil
}
session := rpcRewrapSessionKey{authKeyID: c.authKeyID, sessionID: c.sessionID}
key := rpcRewrapKey{rpcRewrapSessionKey: session, fingerprint: sha256.Sum256(inner)}
r.mu.Lock()
queue := r.byKey[key]
for _, candidate := range queue {
if !candidate.active || candidate.claimed {
continue
}
candidate.claimed = true
r.mu.Unlock()
return candidate
}
r.mu.Unlock()
return nil
}
func (r *rpcRewrapRegistry) commit(candidate *rpcRewrapCandidate) {
if r == nil || candidate == nil {
return
}
r.mu.Lock()
r.removeLocked(candidate)
r.mu.Unlock()
candidate.owner.SetAbortHook(nil)
}
func (r *rpcRewrapRegistry) release(candidate *rpcRewrapCandidate) {
if r == nil || candidate == nil {
return
}
r.mu.Lock()
if candidate.active {
candidate.claimed = false
}
r.mu.Unlock()
}
func (r *rpcRewrapRegistry) remove(candidate *rpcRewrapCandidate) {
if r == nil || candidate == nil {
return
}
r.mu.Lock()
r.removeLocked(candidate)
r.mu.Unlock()
}
// acknowledge retires a candidate only after the client explicitly ACKs the
// physical rpc_result. A successful socket write alone is insufficient proof:
// the client may already have reassigned the request to a new msg_id without
// parsing that old result.
func (r *rpcRewrapRegistry) acknowledge(c *Conn, reqMsgID int64) {
if r == nil || c == nil || reqMsgID == 0 {
return
}
request := rpcRewrapRequestKey{
rpcRewrapSessionKey: rpcRewrapSessionKey{authKeyID: c.authKeyID, sessionID: c.sessionID},
reqMsgID: reqMsgID,
}
r.mu.Lock()
candidate := r.byRequest[request]
r.removeLocked(candidate)
r.mu.Unlock()
if candidate != nil {
candidate.owner.SetAbortHook(nil)
}
}
func (r *rpcRewrapRegistry) removeLocked(candidate *rpcRewrapCandidate) {
if candidate == nil || !candidate.active {
return
}
candidate.active = false
candidate.claimed = false
r.total--
session := candidate.key.rpcRewrapSessionKey
delete(r.byRequest, rpcRewrapRequestKey{rpcRewrapSessionKey: session, reqMsgID: candidate.reqMsgID})
if set := r.bySession[session]; set != nil {
delete(set, candidate)
if len(set) == 0 {
delete(r.bySession, session)
}
}
queue := r.byKey[candidate.key]
for i, existing := range queue {
if existing != candidate {
continue
}
copy(queue[i:], queue[i+1:])
queue[len(queue)-1] = nil
queue = queue[:len(queue)-1]
break
}
if len(queue) == 0 {
delete(r.byKey, candidate.key)
} else {
r.byKey[candidate.key] = queue
}
}
func (r *rpcRewrapRegistry) clearSession(c *Conn) {
if r == nil || c == nil {
return
}
session := rpcRewrapSessionKey{authKeyID: c.authKeyID, sessionID: c.sessionID}
r.mu.Lock()
set := r.bySession[session]
owners := make([]*rpcResultOwnerLease, 0, len(set))
for candidate := range set {
owners = append(owners, candidate.owner)
r.removeLocked(candidate)
}
r.mu.Unlock()
for _, owner := range owners {
owner.SetAbortHook(nil)
}
}
type rpcRewrapInit struct {
layer int
apiID int
deviceModel string
system string
appVersion string
systemLang string
langPack string
langCode string
inner []byte
}
type rpcRewrapRawObject struct {
data []byte
}
func (o *rpcRewrapRawObject) Decode(b *bin.Buffer) error {
if _, err := b.PeekID(); err != nil {
return err
}
o.data = b.Buf
b.Skip(len(b.Buf))
return nil
}
func (o *rpcRewrapRawObject) Encode(b *bin.Buffer) error {
b.Put(o.data)
return nil
}
func decodeRPCRewrapInit(body []byte) (rpcRewrapInit, bool) {
b := &bin.Buffer{Buf: body}
if err := b.ConsumeID(tg.InvokeWithLayerRequestTypeID); err != nil {
return rpcRewrapInit{}, false
}
layer, err := b.Int()
if err != nil || layer <= 0 {
return rpcRewrapInit{}, false
}
raw := &rpcRewrapRawObject{}
req := tg.InitConnectionRequest{Query: raw}
if err := req.Decode(b); err != nil || b.Len() != 0 || len(raw.data) < bin.Word {
return rpcRewrapInit{}, false
}
return rpcRewrapInit{
layer: layer, apiID: req.APIID, deviceModel: req.DeviceModel,
system: req.SystemVersion, appVersion: req.AppVersion,
systemLang: req.SystemLangCode, langPack: req.LangPack, langCode: req.LangCode,
inner: raw.data,
}, true
}
type rpcRewrapAlias struct {
conn *Conn
newReqID int64
method string
oldWaiter *rpcResultWaiter
newOwner *rpcResultOwnerLease
sourceConn *Conn
sourceOwner *rpcResultOwnerLease
retargeted atomic.Bool
observeInit bool
init rpcRewrapInit
candidate *rpcRewrapCandidate
registry *rpcRewrapRegistry
}
var (
rpcRewrapDeliveryOnce sync.Once
rpcRewrapDeliveryJobs chan func()
)
const (
rpcRewrapDeliveryWorkers = 4
rpcRewrapDeliveryQueue = 256
)
func scheduleRPCRewrapDelivery(fn func()) bool {
if fn == nil {
return false
}
rpcRewrapDeliveryOnce.Do(func() {
rpcRewrapDeliveryJobs = make(chan func(), rpcRewrapDeliveryQueue)
for range rpcRewrapDeliveryWorkers {
go func() {
for job := range rpcRewrapDeliveryJobs {
job()
}
}()
}
})
select {
case rpcRewrapDeliveryJobs <- fn:
return true
default:
return false
}
}
func (a *rpcRewrapAlias) activate(s *Server) error {
if a == nil || s == nil || a.conn == nil || a.oldWaiter == nil {
return ErrRPCResultFlightInvalid
}
err := a.oldWaiter.Subscribe(func(encoded *encodedOutboundMessage, ok bool) {
if !ok || encoded == nil {
if a.newOwner != nil {
a.newOwner.Abort()
}
a.conn.fenceUndeliveredRPCResult()
return
}
if a.newOwner == nil {
if !scheduleRPCRewrapDelivery(func() {
ctx, cancel := context.WithTimeout(context.Background(), min(5*time.Second, max(time.Second, a.conn.writeTimeout)))
defer cancel()
if err := s.sendCachedRPCResult(ctx, a.conn, encoded); err != nil && !isClientDisconnect(err) {
s.log.Debug("RPC init rewrap pending replay failed", zap.Error(err))
}
}) {
a.conn.fenceUndeliveredRPCResult()
}
return
}
clone, err := cloneRPCResultForRequest(encoded, a.newReqID, false)
if err != nil {
a.newOwner.Abort()
a.conn.fenceUndeliveredRPCResult()
return
}
if a.retargeted.Load() {
if !a.newOwner.HandOff() {
a.conn.fenceUndeliveredRPCResult()
return
}
clone.markDelivered()
s.storeRPCResult(a.conn, a.newReqID, clone)
s.log.Info("RPC init rewrap result retargeted",
zap.String("method", a.method), zap.Int64("new_req_msg_id", a.newReqID),
zap.String("auth_key_id", a.conn.authKeyHex), zap.Int64("session_id", a.conn.sessionID))
return
}
if !scheduleRPCRewrapDelivery(func() {
s.publishRewrappedRPCResult(a.conn, a.newReqID, a.method, a.newOwner, clone)
}) {
// The completed result is durable in memory. Fence before publishing it
// under the new msg_id so a replacement can replay without re-executing.
a.conn.fenceUndeliveredRPCResult()
if a.newOwner.HandOff() {
clone.markReplayable()
s.storeRPCResult(a.conn, a.newReqID, clone)
}
}
})
if err != nil {
s.rpcRewrap.release(a.candidate)
return err
}
// Subscribe first so every terminal owner event has a consumer. If completion
// wins this race the callback replays under the new ID; if retarget wins, the
// sole outbound actor snapshots the new ID before writing.
if a.newOwner != nil && a.sourceConn == a.conn && a.sourceOwner != nil {
a.retargeted.Store(a.sourceOwner.TryRetarget(a.newReqID))
}
if a.observeInit {
s.scheduleRewrappedInitObservation(a.conn, a.init)
}
s.rpcRewrap.commit(a.candidate)
a.candidate = nil
return nil
}
func (a *rpcRewrapAlias) releaseCandidate() {
if a == nil || a.candidate == nil {
return
}
a.registry.release(a.candidate)
a.candidate = nil
}
func (s *Server) scheduleRewrappedInitObservation(c *Conn, init rpcRewrapInit) {
observer, ok := s.rpc.(RPCInitConnectionObserver)
if !ok || c == nil {
return
}
if !scheduleRPCRewrapDelivery(func() {
ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
defer cancel()
if err := observer.ObserveInitConnection(
ctx, c.authKeyID, c.sessionID, init.layer, init.apiID,
init.deviceModel, init.system, init.appVersion, init.systemLang,
init.langPack, init.langCode,
); err != nil {
s.log.Debug("Observe rewrapped initConnection failed", zap.Error(err))
}
}) {
s.log.Debug("Observe rewrapped initConnection dropped", zap.String("auth_key_id", c.authKeyHex))
}
}
func (s *Server) publishRewrappedRPCResult(c *Conn, reqMsgID int64, method string, owner *rpcResultOwnerLease, encoded *encodedOutboundMessage) {
if s == nil || c == nil || owner == nil || encoded == nil {
return
}
if !owner.HandOff() {
c.fenceUndeliveredRPCResult()
return
}
priority := rpcResultPriority(method, encoded)
encoded.priority = priority
terminal := func(deliveryErr error) {
if deliveryErr != nil {
encoded.markReplayable()
c.fenceUndeliveredRPCResult()
} else {
encoded.markDelivered()
}
s.storeRPCResult(c, reqMsgID, encoded)
}
encoded.markQueued()
ctx, cancel := context.WithTimeout(context.Background(), min(5*time.Second, max(time.Second, c.writeTimeout)))
defer cancel()
if err := c.enqueueEncodedDelivery(ctx, proto.MessageServerResponse, encoded, priority, terminal); err != nil {
terminal(err)
return
}
s.log.Info("RPC init rewrap result replay admitted",
zap.String("method", method), zap.Int64("req_msg_id", reqMsgID),
zap.String("auth_key_id", c.authKeyHex), zap.Int64("session_id", c.sessionID),
zap.Int("wire_bytes", len(encoded.body)))
}