Help us improve your experience.

Let us know what you think.

Do you have time for a two-minute survey?

 

Configuring Reverse Proxy on the SRX Series Device

 

Starting with Junos OS Release 15.1X49-D80 and Junos OS Release 17.3R1, the SRX Series device acts as a proxy, so it can downgrade SSL negotiation to RSA. Other changes are shown in Table 1.

Table 1: Comparing Reverse Proxy Before and After Junos OS Release 15.1X49-D80 and 17.3R1

Feature

Prior to 15.1X49-D80

After 15.1X49-D80 and 17.3R1

Proxy model

Runs only in tap mode Instead of participating in SSL handshake, it listens to the SSL handshake, computes session keys and then decrypts the SSL traffic.

Terminates client SSL on the SRX Series device and initiates a new SSL connection with a server. Decrypts SSL traffic from the client/server and encrypts again (after inspection) before sending to the server/client.

Protocol version

Does not support TLS Version 1.1 and 1.2.

Supports all current protocol versions.

Key exchange methods

Supports RSA.

Supports RSA.

Echo system

Tightly coupled with IDP engine and its detector.

Uses existing SSL forward proxy with TCP proxy underneath.

Security services

Decrypted SSL traffic can be inspected only by IDP.

Just like forward proxy, decrypted SSL traffic is available for all security services.

Ciphers supported

Limited set of ciphers are supported.

All commonly used ciphers are supported.

The remainder of this topic uses the term SSL proxy to denote both forward proxy and reverse proxy.

Like forward proxy, reverse proxy requires a profile to be configured at the firewall rule level. In addition, you must also configure server certificates with private keys for reverse proxy. During an SSL handshake, the SSL proxy performs a lookup for a matching server private key in its server private key hash table database. If the lookup is successful, the handshake continues. Otherwise, SSL proxy terminates the hand shake. Reverse proxy does not prohibit server certificates. It forwards the actual server certificate/chain as is to the client without modifying it. Intercepting the server certificate occurs only with forward proxy. The following shows example forward and reverse proxy profile configurations.

You must configure either root-ca or server-certificate in an SSL proxy profile. Otherwise the commit check fails. See Table 2.

Table 2: Supported SSL Proxy Configurations

server-certificate configured

root-ca configured

Profile type

No

No

Commit check fails. You must configure either server-certificate or root-ca.

Yes

Yes

Commit check fails. Configuring both server-certificate and root-ca in the same profile is not supported.

No

Yes

Forward proxy

Yes

No

Reverse proxy

Configuring multiple instances of forward and reverse proxy profiles are supported. But for a given firewall policy, only one profile (either a forward or reverse proxy profile) can be configured. Configuring both forward and reverse proxy on the same device is also supported.

You cannot configure the previous reverse proxy implementation with the new reverse proxy implementation for a given firewall policy. If both are configured, you will receive a commit check failure message.

The following are the minimum steps to configure reverse proxy:

  1. Load the server certificates and their keys into the SRX Series device certificate repository using the CLI command request security pki local-certificate load filename filename key key certificate-id certificate-id passphrase exmample@1234. For example:
  2. Attach the server certificate identifier to the SSL Proxy profile using the CLI command set services ssl proxy profile profile server-certificate certificate-id passphrase exmample@1234. For example
  3. Use the show services ssl CLI command to verify your configuration. For example: