You could use tcp-ssl:port configuration in inputs.conf
* Use this stanza type if you are receiving encrypted, unparsed data from a
forwarder or third-party system.
* Set <port> to the port on which the forwarder/third-party system is sending
unparsed, encrypted data.
* To create multiple SSL inputs, you can add the following attributes to each
[tcp-ssl:<port>] input stanza. If you do not configure a certificate in the
port, the certificate information is pulled from the default [SSL] stanza:
* serverCert = <path_to_cert>
* sslRootCAPath = <path_to_cert> This attribute should only be added
if you have not configured your sslRootPath in server.conf.
* sslPassword = <password>