• SonicOS 7 Rules and Policies
• Access Rules
  • Setting Firewall Access Rules
    • About Stateful Packet Inspection Default Access Rules
    • About Connection Limiting
    • Using Bandwidth Management with Access Rules
      • Enabling Bandwidth Management on an Access Rule
    • Configuring Access Rules
      • Configuring Access Rules for IPv6
      • Configuring Access Rules for NAT64
      • Access Rules for DNS Proxy
      • User Priority for Access Rules
      • Displaying Access Rules
        • By Zones
        • By Column
      • Configuring Access Rules for a Zone
    • Enabling and Disabling Access Rules
    • Editing Access Rules
    • Deleting Access Rules
    • Restoring Access Rules to Default Settings
    • Displaying Access Rule Traffic Statistics
  • Access Rule Configuration Examples
    • Enabling Ping
    • Blocking LAN Access for Specific Services
    • Allowing WAN Primary IP Access from the LAN Zone
• NAT Rules
  • About NAT in SonicOS
  • About NAT Load Balancing
    • Determining the NAT LB Method to Use
    • Caveats
    • How Load Balancing Algorithms are Applied
    • Sticky IP Algorithm Examples
      • Example One - Mapping to a Network
      • Example Two - Mapping to an IP Address Range
  • About NAT64
    • Use of Pref64::/n
  • About FQDN-based NAT
  • About Source MAC Address Override
  • Viewing NAT Policy Entries
    • Changing the Display
    • Filtering the Display
    • Displaying Information about Policies
  • Adding or Editing NAT or NAT64 Policies
  • Deleting NAT Policies
  • Creating NAT Rule Policies: Examples
    • Creating a One-to-One NAT Policy for Inbound Traffic
    • Creating a One-to-One NAT Policy for Outbound Traffic
    • Inbound Port Address Translation via One-to-One NAT Policy
    • Inbound Port Address Translation via WAN IP Address
    • Creating a Many-to-One NAT Policy
    • Creating a Many-to-Many NAT Policy
    • Creating a One-to-Many NAT Load Balancing Policy
    • Creating a NAT Load Balancing Policy for Two Web Servers
    • Creating a WAN-to-WAN Access Rule for a NAT64 Policy
    • DNS Doctoring
• Routing Rules
  • About Routing
    • About Metrics and Administrative Distance
      • About Metrics
      • About Administrative Distance
    • Route Advertisement
    • ECMP Routing
    • Policy-based Routing
    • Policy-based TOS Routing
    • PBR Metric-based Priority
    • Policy-based Routing and IPv6
    • OSPF and RIP Advanced Routing Services
      • About Routing Services
        • Protocol Type
        • Maximum Hops
        • Split-Horizon
        • Poison Reverse
        • Routing Table Updates
        • Subnet Sizes Supported
        • Autonomous System Topologies
      • OSPF Terms
    • Drop Tunnel Interface
    • App-based Routing
  • Rules and Policies > Routing Rules
    • Configuring Routing Rules
      • Adding Static Routes
      • Probe-Enabled Policy-based Routing Configuration
• Content Filter Rules
  • About Content Filtering Rules (CFS)
    • About Content Filter Rules
    • About UUIDs for CFS Policies
    • About Content Filter Objects
    • How CFS Works
  • Configuring CFS Policies
    • About the Content Filter Rule Table
      • Searching the Content Filter Rule Table
    • Adding a Content Filter Rule
    • Editing a Content Filter Rule
    • Deleting Content Filter Rules
• App Rules
  • About App Rules
    • What are App Rules?
      • About App Rules Policies
      • About App Rules Capabilities
    • Benefits of App Rules
    • How Does Application Control Work?
    • About App Rules Policy Creation
    • Licensing App Rules and App Control
    • Terminology
  • Rules and Policies > App Rules
    • Configuring an App Rules Policy
    • Using the App Rule Wizard
  • Verifying App Rules Configuration
    • Useful Tools
      • Wireshark
      • Hex Editor
  • App Rules Use Cases
    • Creating a Regular Expression in a Match Object
    • Policy-based Application Rules
    • Logging Application Signature-based Policies
    • Compliance Enforcement
    • Server Protection
    • Hosted Email Environments
    • Email Control
    • Web Browser Control
    • HTTP Post Control
    • Forbidden File Type Control
    • ActiveX Control
    • FTP Control
      • Blocking Outbound Proprietary Files Over FTP
      • Blocking Outbound UTF-8 / UTF-16 Encoded Files
      • Blocking FTP Commands
    • Bandwidth Management
    • Bypass DPI
    • Custom Signature
    • Reverse Shell Exploit Prevention
      • Generating the Network Activity
      • Capturing and Exporting the Payload to a Text File Using Wireshark
      • Creating a Match Object
      • Defining the Policy
• Endpoint Rules
• SonicWall Support
  • About This Document

Blocking Outbound UTF-8 / UTF-16 Encoded Files

Native Unicode UTF-8 and UTF-16 support by App Rules allows encoded multi-byte characters, such as Chinese or Japanese characters, to be entered as match object content keywords using the alphanumeric input type. App Rules supports keyword matching of UTF-8 encoded content typically found in Web pages and email applications, and UTF-16 encoded content typically found in Windows OS/Microsoft Office-based documents.

Blocking outbound file transfers of proprietary Unicode files over FTP is handled in the same way as blocking other confidential file transfers:

1. Create a match object that matches on UTF-8 or UTF-16 encoded keywords in files.

2. Create a policy that references the match object and blocks transfer of matching files.

   The example that follows uses a match object type of File Content with a UTF-16 encoded Chinese keyword that translates as “confidential document.”

   

3. Create a policy that references the match object as follows. This policy blocks the file transfer and resets the connection. Enable Logging is selected so that any attempt to transfer a file containing the UTF-16 encoded keyword is logged.

   

   A log entry is generated after a connection Reset/Drop. An example of a log entry is shown below, including the Message stating that it is an Application Control Alert, displaying the Policy name and the Action Type of Reset/Drop.