VMess AEAD based packet length

(cherry picked from commit 08221600082a79376bdc262f2ffec1a3129ae98d)

proxy/vmess/account.go

@@ -1,6 +1,8 @@
 package vmess
 
 import (
+	"strings"
+
 	"github.com/xtls/xray-core/common/dice"
 	"github.com/xtls/xray-core/common/protocol"
 	"github.com/xtls/xray-core/common/uuid"
@@ -14,6 +16,8 @@ type MemoryAccount struct {
 	AlterIDs []*protocol.ID
 	// Security type of the account. Used for client connections.
 	Security protocol.SecurityType
+
+	AuthenticatedLengthExperiment bool
 }
 
 // AnyValidID returns an ID that is either the main ID or one of the alternative IDs if any.
@@ -41,9 +45,14 @@ func (a *Account) AsAccount() (protocol.Account, error) {
 		return nil, newError("failed to parse ID").Base(err).AtError()
 	}
 	protoID := protocol.NewID(id)
+	var AuthenticatedLength bool
+	if strings.Contains(a.TestsEnabled, "AuthenticatedLength") {
+		AuthenticatedLength = true
+	}
 	return &MemoryAccount{
-		ID:       protoID,
-		AlterIDs: protocol.NewAlterIDs(protoID, uint16(a.AlterId)),
-		Security: a.SecuritySettings.GetSecurityType(),
+		ID:                            protoID,
+		AlterIDs:                      protocol.NewAlterIDs(protoID, uint16(a.AlterId)),
+		Security:                      a.SecuritySettings.GetSecurityType(),
+		AuthenticatedLengthExperiment: AuthenticatedLength,
 	}, nil
 }