Configure SSL Inbound Inspection

1. Ensure that the appropriate interfaces are configured as either Tap, Virtual Wire, Layer 2, or Layer 3 interfaces.
   You cannot use a Tap mode interface for SSL Inbound Inspection if the negotiated ciphers include PFS key exchange algorithms (DHE and ECDHE).

   View configured interfaces on the NetworkInterfacesEthernet tab. The Interface Type column displays if an interface is configured to be a Virtual Wire, Layer 2, or Layer 3 interface. You can select an interface to modify its configuration, including the interface type.
2. Ensure that the targeted server certificate is installed on the firewall.
   On the web interface, select DeviceCertificate ManagementCertificatesDevice Certificates to view certificates installed on the firewall.

   We recommend uploading a certificate chain (a single file) to the firewall if your end-entity (leaf) certificate is signed by one or more intermediate certificates and your web server supports TLS 1.2 and PFS key exchange algorithms. Uploading the chain avoids client-side server certificate authentication issues. You should arrange the certificates in the file as follows:

   1. End-entity (leaf) certificate
   2. Intermediate certificates (in issuing order)
   3. (Optional) Root certificate

   You can upload the server certificate and private key alone to the firewall if your web server supports only TLS 1.2 and the RSA key exchange algorithm and the server’s certificate chain (if the leaf certificate is signed by intermediate certificates) is installed on the server. SSL Inbound Inspection discusses each case in more detail.

   To import the targeted server certificate onto the firewall:
   1. On the Device Certificates tab, select Import.
   2. Enter a descriptive Certificate Name.
   3. Browse for and select the targeted server Certificate File.
   4. Click OK.
3. Create a Decryption policy rule to define traffic for the firewall to decrypt and create a Decryption profile to apply SSL controls to the traffic.
   Although Decryption profiles are optional, it is best to include a Decryption profile with each Decryption policy rule to prevent weak, vulnerable protocols and algorithms from allowing questionable traffic on your network.
   1. Select PoliciesDecryption, Add or modify an existing rule, and define the traffic to be decrypted.
   2. Select Options and:
      • Set the Action to Decrypt matching traffic.
      • Set the Type to SSL Inbound Inspection.
      • Select the Certificate for the internal server that is the destination of the inbound SSL traffic.
      • (Optional but a best practice) Configure or select an existing Decryption Profile to block and control various aspects of the decrypted traffic (for example, create a Decryption profile to terminate sessions with unsupported algorithms and unsupported cipher suites).
        When you configure the SSL Protocol Settings Decryption Profile for SSL Inbound Inspection traffic, create separate profiles for servers with different security capabilities. For example, if one set of servers supports only RSA, the SSL Protocol Settings only need to support RSA. However, the SSL Protocol Settings for servers that support PFS should support PFS. Configure SSL Protocol Settings for the highest level of security that the server supports, but check performance to ensure that the firewall resources can handle the higher processing load that higher security protocols and algorithms require.
   3. Click OK to save.
4. Enable the firewall to forward decrypted SSL traffic for WildFire analysis.
   This option requires an active WildFire license and is a WildFire best practice.
5. Commit the configuration.
6. Choose your next step...
   • Enable Users to Opt Out of SSL Decryption.
   • Configure Decryption exclusions to disable decryption for certain types of traffic.