Use dc indexes accordingly

mtglib/internal/obfuscated2/handshake_frame.go

@@ -3,6 +3,8 @@ package obfuscated2
 import "encoding/binary"
 
 const (
+	DefaultDC = 2
+
 	handshakeFrameLen = 64
 
 	handshakeFrameLenKey            = 32
@@ -41,11 +43,11 @@ func (h *handshakeFrame) dc() int {
 
 	switch {
 	case idx > 0:
-		return int(idx) - 1
+		return int(idx)
 	case idx < 0:
-		return -int(idx + 1)
+		return -int(idx)
 	default:
-		return 0
+		return DefaultDC
 	}
 }
 

mtglib/internal/obfuscated2/handshake_frame_internal_test.go

@@ -31,13 +31,13 @@ func (suite *HandshakeFrameTestSuite) TestOk() {
 	suite.Equal("zyjgwaWXlTP6qjVMUP2scQbqdUtspmyH1Hen+2Ess8w", suite.Encode(hf.key()))
 	suite.Equal("z0SZMW/b9fMaokYQe6PbOg", suite.Encode(hf.iv()))
 	suite.Equal("H5lBgQ", suite.Encode(hf.connectionType()))
-	suite.EqualValues(2093, hf.dc())
+	suite.EqualValues(2094, hf.dc())
 
 	inverted := hf.invert()
 	suite.Equal("OtujexBGohrz9dtvMZlEz8yzLGH7p3fUh2ymbEt16gY", suite.Encode(inverted.key()))
 	suite.Equal("caz9UEw1qvozlZelweAozw", suite.Encode(inverted.iv()))
 	suite.Equal("H5lBgQ", suite.Encode(inverted.connectionType()))
-	suite.EqualValues(2093, inverted.dc())
+	suite.EqualValues(2094, inverted.dc())
 }
 
 func TestHandshakeFrame(t *testing.T) {

mtglib/internal/obfuscated2/testdata/client-handshake-snapshot-4529d55776e2d427.json

@@ -1,7 +1,7 @@
 {
   "secret": "NnoYmu4Y+jHBkAVO/UqOlQ",
   "frame": "gDcXwaMY4RwlR+nJw+ILDr123UJHHjjE/U5pF4m/Y04AmH7lEpEL6UYRnIYDbDlOHSDxc1ToziPvNlJJh8RMow",
-  "dc": 1,
+  "dc": 2,
   "encrypted": {
     "text": "AQIDBAUGBwgJCg",
     "cipher": "wZV3TR39l9nRoQ"

mtglib/internal/obfuscated2/testdata/client-handshake-snapshot-585c944d672f60a2.json

@@ -1,7 +1,7 @@
 {
   "secret": "NnoYmu4Y+jHBkAVO/UqOlQ",
   "frame": "M2WyxeiwIQB+ZOFxNzSNHtu9OdESkfxv3JkKFimCxUoYA3BD/Ql9nXB/OIonCKLUKCcS0VzZ2P6/+5oQ9GI8YA",
-  "dc": 1,
+  "dc": 2,
   "encrypted": {
     "text": "AQIDBAUGBwgJCg",
     "cipher": "tzAwrCz00odERg"