Manual Chapter : Implementing SSL Forward Proxy on a Single BIG-IP System

Applies To:

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BIG-IP DNS

  • 14.0.0

BIG-IP AFM

  • 14.0.0

BIG-IP Analytics

  • 14.0.0

BIG-IP PEM

  • 14.0.0

BIG-IP ASM

  • 14.0.0

BIG-IP AAM

  • 14.0.0

BIG-IP APM

  • 14.0.0

BIG-IP LTM

  • 14.0.0
Manual Chapter

Implementing SSL Forward Proxy on a Single BIG-IP System

Overview: SSL forward proxy client and server authentication

With the BIG-IP® system's
SSL forward proxy
functionality, you can encrypt all traffic between a client and the BIG-IP system, by using one certificate, and to encrypt all traffic between the BIG-IP system and the server, by using a different certificate.
A client establishes a three-way handshake and SSL connection with the wildcard IP address of the BIG-IP system virtual server. The BIG-IP system then establishes a three-way handshake and SSL connection with the server, and receives and validates a server certificate (while maintaining the separate connection with the client). The BIG-IP system uses the server certificate to create a second unique server certificate to send to the client. The client receives the second server certificate from the BIG-IP system, but recognizes the certificate as originating directly from the server.
To enable SSL forward proxy functionality, you can either:
  • Disassociate existing Client SSL and Server SSL profiles from a virtual server and configure the SSL Forward Proxy settings.
  • Create new Client SSL and Server SSL profiles and configure the SSL Forward Proxy settings.
Then with either option, select the Client SSL and Server SSL profiles on a virtual server. You cannot modify existing Client SSL and Server SSL profiles while they are selected on a virtual server to enable SSL forward proxy functionality.
A virtual server configured with Client and Server SSL profiles for SSL forward proxy functionality
A virtual server configured with Client and Server SSL profiles for SSL forward proxy     functionality
  1. Client establishes three-way handshake and SSL connection with wildcard IP address.
  2. BIG-IP system establishes three-way handshake and SSL connection with server.
  3. BIG-IP system validates a server certificate (Certificate A), while maintaining the separate connection with the client.
  4. BIG-IP system creates different server certificate (Certificate B) and sends it to client.

Task summary for SSL Forward Proxy on a single BIG-IP system

To implement SSL forward proxy client-to-server authentication, as well as application data manipulation, you perform a few basic configuration tasks. Note that you must create both a Client SSL and a Server SSL profile, and enable the SSL Forward Proxy feature in both profiles.

Creating a custom Client SSL forward proxy profile

You perform this task to create a Client SSL forward proxy profile that makes it possible for client and server authentication while still allowing the BIG-IP system to perform data optimization, such as decryption and encryption. This profile applies to client-side SSL forward proxy traffic only.
  1. On the Main tab, click
    Local Traffic
    Profiles
    SSL
    Client
    .
    The Client SSL profile list screen opens.
  2. Click
    Create
    .
    The New Client SSL Profile screen opens.
  3. In the
    Name
    field, type a unique name for the profile.
  4. From the
    Parent Profile
    list, select
    clientssl
    .
  5. From the
    SSL Forward Proxy
    list, select
    Advanced
    .
  6. Select the
    Custom
    check box for the SSL Forward Proxy area.
  7. Modify the SSL Forward Proxy settings.
    1. From the
      SSL Forward Proxy
      list, select
      Enabled
      .
    2. From the
      CA Certificate
      list, select a certificate.
      If the BIG-IP system is part of a DSC Sync-Failover group, always select a non-default certificate name, and ensure that this same certificate name is specified in every instance of this SSL profile in the device group. Taking these actions helps to ensure that SSL handshakes are successful after a failover event.
    3. From the
      CA Key
      list, select a key.
      If the BIG-IP system is part of a DSC Sync-Failover group, always select a non-default key name, and ensure that this same key name is specified in every instance of this SSL profile in the device group. Taking these actions helps to ensure that SSL handshakes are successful after a failover event.
    4. In the
      CA Passphrase
      field, type a passphrase.
    5. In the
      Confirm CA Passphrase
      field, type the passphrase again.
    6. In the
      Certificate Lifespan
      field, type a lifespan for the SSL forward proxy certificate in days.
    7. From the
      Certificate Extensions
      list, select
      Extensions List
      .
    8. For the
      Certificate Extensions List
      setting, select the extensions that you want in the
      Available extensions
      field, and move them to the
      Enabled Extensions
      field using the
      Enable
      button.
    9. Select the
      Cache Certificate by Addr-Port
      check box if you want to cache certificates by IP address and port number.
    10. From the
      SSL Forward Proxy Bypass
      list, select
      Enabled
      .
      Additional settings display.
    11. From the
      Bypass Default Action
      list, select
      Intercept
      or
      Bypass
      .
      The default action applies to addresses and hostnames that do not match any entry specified in the lists that you specify. The system matches traffic first against destination IP address lists, then source IP address lists, and lastly, hostname lists. Within these, the default action also specifies whether to search the intercept list or the bypass list first.
      If you select
      Bypass
      and do not specify any additional settings, you introduce a security risk to your system.
  8. Click
    Finished
    .
The custom Client SSL forward proxy profile now appears in the Client SSL profile list screen.

Creating a custom Server SSL forward proxy profile

You perform this task to create a Server SSL forward proxy profile that makes it possible for client and server authentication while still allowing the BIG-IP system to perform data optimization, such as decryption and encryption. This profile applies to server-side SSL forward proxy traffic only.
  1. On the Main tab, click
    Local Traffic
    Profiles
    SSL
    Server
    .
    The Server SSL profile list screen opens.
  2. Click
    Create
    .
    The New Server SSL Profile screen opens.
  3. In the
    Name
    field, type a unique name for the profile.
  4. From the
    Parent Profile
    list select
    serverssl
    .
  5. Select the
    Custom
    check box for the Configuration area.
  6. From the
    SSL Forward Proxy
    list, select
    Enabled
    .
  7. Click
    Finished
    .
The custom Server SSL forward proxy profile now appears in the Server SSL profile list screen.

Creating a load balancing pool

Ensure that at least one virtual server exists in the configuration before you start to create a load balancing pool.
Create a pool of systems with Access Policy Manager to which the system can load balance global traffic.
  1. On the Main tab, click
    DNS
    GSLB
    Pools
    .
    The Pool List screen opens.
  2. Click
    Create
    .
    The New Pool screen opens.
  3. In the General Properties area, in the
    Name
    field, type a name for the pool.
    Names must begin with a letter, and can contain only letters, numbers, and the underscore (_) character.
    The pool name is limited to 63 characters.
  4. From the
    Type
    list, depending on the type of the system (IPv4 or IPv6), select either an
    A
    or
    AAAA
    pool type.
  5. In the Configuration area, for the
    Health Monitors
    setting, in the
    Available
    list, select a monitor type, and move the monitor to the
    Selected
    list.
    Hold the Shift or Ctrl key to select more than one monitor at a time.
  6. In the Members area, for the
    Load Balancing Method
    settings, select a method that uses virtual server score:
    • VS Score - If you select this method, load balancing decisions are based on the virtual server score only.
    • Quality of Service - If you select this method, you must configure weights for up to nine measures of service, including
      VS Score
      . Virtual server score then factors into the load balancing decision at the weight you specify.
  7. For the
    Member List
    setting, add virtual servers as members of this load balancing pool.
    The system evaluates the virtual servers (pool members) in the order in which they are listed. A virtual server can belong to more than one pool.
    1. Select a virtual server from the
      Virtual Server
      list.
    2. Click
      Add
      .
  8. Click
    Finished
    .

Creating a virtual server for client-side and server-side SSL traffic

You can specify a virtual server to be either a host virtual server or a network virtual server to manage application traffic.
  1. On the Main tab, click
    Local Traffic
    Virtual Servers
    .
    The Virtual Server List screen opens.
  2. Click the
    Create
    button.
    The New Virtual Server screen opens.
  3. In the
    Name
    field, type a unique name for the virtual server.
  4. For a network, in the
    Destination Address/Mask
    field, type an IPv4 or IPv6 address in CIDR format to allow all traffic to be translated.
    The supported format is address/prefix, where the prefix length is in bits. For example, an IPv4 address/prefix is
    0.0.0.0/0
    , and an IPv6 address/prefix is
    ::/0
    .
  5. In the
    Service Port
    field:
    • If you want to specify a single service port or all ports, confirm that the
      Port
      button is selected, and type or select a service port.
    • If you want to specify multiple ports other than all ports, select the
      Port List
      button, and confirm that the port list that you previously created appears in the box.
  6. For the
    SSL Profile (Client)
    setting, from the
    Available
    list, select the name of the Client SSL forward proxy profile you previously created, and using the Move button, move the name to the
    Selected
    list.
    To enable SSL forward proxy functionality, you can either:
    • Disassociate existing Client SSL and Server SSL profiles from a virtual server and configure the SSL Forward Proxy settings.
    • Create new Client SSL and Server SSL profiles and configure the SSL Forward Proxy settings.
    Then with either option, select the Client SSL and Server SSL profiles on a virtual server. You cannot modify existing Client SSL and Server SSL profiles while they are selected on a virtual server to enable SSL forward proxy functionality.
  7. For the
    SSL Profile (Server)
    setting, from the
    Available
    list, select the name of the Server SSL forward proxy profile you previously created, and using the Move button, move the name to the
    Selected
    list.
    To enable SSL forward proxy functionality, you can either:
    • Disassociate existing Client SSL and Server SSL profiles from a virtual server and configure the SSL Forward Proxy settings.
    • Create new Client SSL and Server SSL profiles and configure the SSL Forward Proxy settings.
    Then with either option, select the Client SSL and Server SSL profiles on a virtual server. You cannot modify existing Client SSL and Server SSL profiles while they are selected on a virtual server to enable SSL forward proxy functionality.
  8. Assign other profiles to the virtual server if applicable.
  9. In the Resources area, from the
    Default Pool
    list, select the name of the pool that you created previously.
  10. Click
    Finished
    .
The virtual server now appears in the Virtual Server List screen.

Implementation result

After you complete the tasks in this implementation, the BIG-IP® system ensures that the client system and server system can authenticate each other independently. After client and server authentication, the BIG-IP system can intelligently decrypt and manipulate the application data according to the configuration settings in the profiles assigned to the virtual server.