Sunday, September 5, 2021

Gofang Prophecy (PRO-Matrix44-SC) controls

Picked up a second-hand Gofanco Prophecy (PRO-Matrix44-SC) HDMI matrix (4 in/4 out, with Ethernet). Fired up Burp and figured out how to manage it with curl POST statements.

Syntax amounts to:

    curl -d "COMMAND" -s -X POST http:///inform.cgi

Where COMMAND is one of:

  • poweron - which turns the matrix on
  • poweroff - which turns the matrix off
  • outX=Y - which switches output X (1-4) to input Y (1-4)

Apparently, the matrix has a controller which keeps on listening, even when the matrix is disabled. This is a nice to have feature as it allows for the network-based power-on.

For now, the matrix is a bit of overkill, since I typically run just the server and the laptop, but it's nice to swap out what is displaying on which of two display. It does give root to expand.

I also picked up a couple 4-button keyboards from Amazon that I'll mix in, to provide management of each monitor's display via the above curl commands.

The matrix supposedly also has an Alexa interface. That's for later experimentation, I think.

Thursday, September 2, 2021

Modify any web page before printing it

It's the little things that have the greatest impact...

I keep an archive of PDF-ified web pages that I find valuable. They're searchable because I use Recoll to index them, along with the web-ui front-end.

The below makes cleaning up a web page easy, so that it can be saved to PDF.

Create a bookmark and enter the following in the URL field:

    javascript:document.body.contentEditable = 'true'; document.designMode='on'; void 0

When you have that, go to the web page that you want to save, click on the above bookmark and modify the page as you would in a word processor or text editor. You can then call up the browser's print function and save the page as a PDF.

Saturday, August 7, 2021

Fixing wlan interface name after using airmon-ng

One for the students' notebooks...

If you have an interface named (as an example) "wlan16" and you attach airmon-ng to it, then exit ungracefully (e.g., via ctrl-c), you probably notice that you now have an interface named "wlan16mon". The repair is quite easy.

1) Use iwconfig to check that the interace is still in monitor mode.

    iwconfig wlan16mon
If it isn't in monitor mode (e.g., you've been messing with it and changed the mode), return it to monitor mode via:
    ifconfig wlan16mon down
    iwconfig wlan16mon mode monitor

2) Use the following airmon-ng to stop the interface and return the name to normal.

    airmon-ng stop wlan16mon

3) Check the interface