Offer a Setting to allow remote connections to Zed lake service

[philrz]

The command line currently created by Brim when launching zqd (such as in GA Brim tagged v0.18.0) prevents remote access because the option -l localhost:9867 specifies localhost. This makes sense as a default. However, if is this were shortened to merely -l :9867, the zqd would be prepared to accept remote connections. Therefore we could make this an option that could be enabled in the Preferences menu.

A possible use case might be for a user that's running a Capture The Flag event and has imported some pcaps and logs via Brim and wants to quickly make them accessible to participants.

[philrz]

As described in bug #3056, for the past couple GA Zui releases, remote connections have been allowed by default. Once that's been tightened up by default again I can look at adding this new setting to open it up again when a user explicitly wants that.

[philrz]

Verified in Zui Insiders 1.8.1-insiders.7 which is based on Zui commit 4077181.

In the attached video I'm running Zui Insiders on my Macbook and also in a Linux VM inside VirtualBox with a Port Forwarding config such that when I connect to localhost:9999 from my Macbook the connection goes through to port 9988 in the VM, i.e., it's seen as an incoming remote connection. At defaults, when I click Add Lake... in the Zui Insiders on my Macbook and attempt to connect to http://localhost:9999, the connection is not successful because the Zed lake service launched by the Zui Insiders in the Linux VM is only listening for connections from localhost. Once I go into Settings in the Zui Insiders in the Linux VM and toggle the change such that it's now listening to remote connections from Anywhere, now my remote connection succeeds. Likewise when I toggle it back, the connectivity is no longer permitted.

Verify.mp4