Msgid fix

internal/mtproto/messages/messages.go

@@ -18,6 +18,7 @@ import (
 
 	ige "github.com/xelaj/mtproto/internal/aes_ige"
 	"github.com/xelaj/mtproto/internal/encoding/tl"
+	"github.com/xelaj/mtproto/internal/mtproto"
 	"github.com/xelaj/mtproto/internal/utils"
 )
 
@@ -30,7 +31,7 @@ type Common interface {
 
 type Encrypted struct {
 	Msg         []byte
-	MsgID       int64
+	MsgID       mtproto.MsgID
 	AuthKeyHash []byte
 
 	Salt      int64
@@ -82,7 +83,7 @@ func DeserializeEncrypted(data, authKey []byte) (*Encrypted, error) {
 	}
 	msg.Salt = d.PopLong()
 	msg.SessionID = d.PopLong()
-	msg.MsgID = d.PopLong()
+	msg.MsgID = mtproto.MsgID(d.PopLong())
 	msg.SeqNo = d.PopInt()
 	messageLen := d.PopInt()
 
@@ -119,15 +120,15 @@ func (msg *Encrypted) GetSeqNo() int {
 
 type Unencrypted struct {
 	Msg   []byte
-	MsgID int64
+	MsgID mtproto.MsgID
 }
 
 func (msg *Unencrypted) Serialize(client MessageInformator) ([]byte, error) {
 	buf := bytes.NewBuffer(nil)
 	e := tl.NewEncoder(buf)
 	// authKeyHash, always 0 if unencrypted
 	e.PutLong(0)
-	e.PutLong(msg.MsgID)
+	e.PutLong(int64(msg.MsgID))
 	e.PutInt(int32(len(msg.Msg)))
 	e.PutRawBytes(msg.Msg)
 	return buf.Bytes(), nil
@@ -138,7 +139,7 @@ func DeserializeUnencrypted(data []byte) (*Unencrypted, error) {
 	d, _ := tl.NewDecoder(bytes.NewBuffer(data))
 	_ = d.PopRawBytes(tl.LongLen) // authKeyHash, always 0 if unencrypted
 
-	msg.MsgID = d.PopLong()
+	msg.MsgID = mtproto.MsgID(d.PopLong())
 
 	mod := msg.MsgID & 3
 	if mod != 1 && mod != 3 {
@@ -183,15 +184,15 @@ type MessageInformator interface {
 	GetAuthKey() []byte
 }
 
-func serializePacket(client MessageInformator, msg []byte, messageID int64, requireToAck bool) []byte {
+func serializePacket(client MessageInformator, msg []byte, id mtproto.MsgID, requireToAck bool) []byte {
 	buf := bytes.NewBuffer(nil)
 	d := tl.NewEncoder(buf)
 
 	saltBytes := make([]byte, tl.LongLen)
 	binary.LittleEndian.PutUint64(saltBytes, uint64(client.GetServerSalt()))
 	d.PutRawBytes(saltBytes)
 	d.PutLong(client.GetSessionID())
-	d.PutLong(messageID)
+	d.PutLong(int64(id))
 	if requireToAck { // не спрашивай, как это работает
 		d.PutInt(client.GetSeqNo() | 1) // почему тут добавляется бит не ебу
 	} else {

internal/mtproto/msg_id.go

@@ -0,0 +1,53 @@
+package mtproto
+
+import (
+	"crypto/rand"
+	"encoding/binary"
+	"math"
+	"time"
+)
+
+const (
+	minDiff = 300 * time.Second
+	maxDiff = -30 * time.Second
+)
+
+type MsgTyp uint8
+
+const (
+	MsgClient     MsgTyp = 0b00
+	MsgServerResp MsgTyp = 0b01
+	MsgServerUpd  MsgTyp = 0b11
+)
+
+// https://core.telegram.org/mtproto/description#message-identifier-msg-id
+// 1-32:  current unix time
+// 33-62: random bits
+// 63:    for server-side only: 0 if msg is answer to request, 1 if server update
+// 64:    1 if msg server-side, 0 if client-side
+type MsgID uint64
+
+func (m MsgID) At() time.Time { return time.Unix(int64(m)>>32, 0) }
+
+func (m MsgID) IsValid(at time.Time) bool {
+	t := m.At().Sub(at)
+	return minDiff > t && t > maxDiff
+}
+
+func NewMsgID(at time.Time, typ MsgTyp) MsgID {
+	if typ >= 4 {
+		panic("invalid type")
+	}
+
+	timePart := uint64(at.Unix()) << 32
+	randPart := randUint32() & (math.MaxUint32 - 3)
+	return MsgID(timePart) | MsgID(randPart) | MsgID(typ)
+}
+
+func randUint32() uint32 {
+	b := make([]byte, 4)
+	if _, err := rand.Read(b); err != nil {
+		panic("unreachable") // to be sure that we will never get any problems
+	}
+	return binary.LittleEndian.Uint32(b)
+}

internal/utils/utils.go

@@ -18,12 +18,16 @@ import (
 
 // GenerateMessageId отдает по сути unix timestamp но ужасно специфическим образом
 // TODO: нахуя нужно битовое и на -4??
-func GenerateMessageId() int64 {
+func GenerateMessageId(prevID int64) int64 {
 	const billion = 1000 * 1000 * 1000
 	unixnano := time.Now().UnixNano()
 	seconds := unixnano / billion
 	nanoseconds := unixnano % billion
-	return (seconds << 32) | (nanoseconds & -4)
+	newID := (seconds << 32) | (nanoseconds & -4)
+	if newID <= prevID {
+		return GenerateMessageId(prevID)
+	}
+	return newID
 }
 
 func AuthKeyHash(key []byte) []byte {

network.go

@@ -8,14 +8,15 @@ package mtproto
 import (
 	"reflect"
 	"strconv"
+	"time"
 
 	"github.com/pkg/errors"
 	"github.com/xelaj/errs"
 
 	"github.com/xelaj/mtproto/internal/encoding/tl"
+	"github.com/xelaj/mtproto/internal/mtproto"
 	"github.com/xelaj/mtproto/internal/mtproto/messages"
 	"github.com/xelaj/mtproto/internal/mtproto/objects"
-	"github.com/xelaj/mtproto/internal/utils"
 )
 
 func (m *MTProto) sendPacket(request tl.Object, expectedTypes ...reflect.Type) (chan tl.Object, error) {
@@ -26,7 +27,7 @@ func (m *MTProto) sendPacket(request tl.Object, expectedTypes ...reflect.Type) (
 
 	var (
 		data  messages.Common
-		msgID = utils.GenerateMessageId()
+		msgID = mtproto.NewMsgID(time.Now(), mtproto.MsgClient)
 	)
 
 	// adding types for parser if required