Informatic

This is just a dump of some interesting undocumented features of webOS (3.8 specifically, on early 2018 4k LG TV) and other development-related tips.

Homebrew app ideas

• OpenVPN frontend (OpenVPN itself is easily buildable and runs on webOS TVs: https://discord.com/channels/407937994037919756/835489130967859251/906943542457401395)
• App autostart manager - dynamically update arbitrary app config and register it as input (see Registering an app as an input)
• webos-vncserver frontend with autostart option
• Package hyperiond into Piccap directly
• Quick Screenshot (expose HTTP port that just returns PNG of current screen contents)
• Custom IR remote codes editor/updater/blaster

Informatic

cloud-init is absolute cancer. Its code is horrible. It has no documentation at all.

It took me 5 fucking hours to figure out how to properly configure networking on recent cloud-init (Ubuntu 16.04 cloud image) with local datasource.

It's not mentioned anywhere you need to provide dsmode: local. (but only if you need network-config, besides that everything is fine; someone below noted that -m flag does the same thing, good to know) Of course nobody needs documentation for network-config format either. (cloudinit/net/__init__.py is a protip, enjoy the feces dive)

Oh, and by the way - no, it's not possible to provide network-config to uvt-kvm without patching shit.

Informatic

<domain type='kvm' xmlns:qemu='http://libvirt.org/schemas/domain/qemu/1.0'>
  <!-- ... -->
  <qemu:commandline>
    <qemu:arg value='-acpitable'/>
    <qemu:arg value='file=/some/path/slic.bin'/>
    <qemu:arg value='-acpitable'/>
    <qemu:arg value='file=/some/path/msdm.bin'/>
    <qemu:arg value='-smbios'/>
    <qemu:arg value='file=/some/path/smbios_type_0.bin'/>
    <qemu:arg value='-smbios'/>

Informatic

  import <nixpkgs> {
    overlays = [
      (final: prev: {
        gst_all_1 = prev.gst_all_1 // {
          gst-plugins-base = prev.gst_all_1.gst-plugins-base.overrideAttrs (p: {
            buildInputs = p.buildInputs ++ [ pkgs.libdrm ];
          });
        };
      })
    ];

Informatic

This is a quick list of cool payloads that can be pushed onto some common MCU boards to turn these them into actually useful everyday hacking tools.

• STM32F1 / Bluepill
  • blackmagic probe - SWD + UART adapter - https://medium.com/@paramaggarwal/converting-an-stm32f103-board-to-a-black-magic-probe-c013cf2cc38c - also a tip on how to use native UART bootloader
  • bluepill_ch341a - CH341A-compatible device (SPI EEPROM + UART)
  • i2c-star - I2C adapter (i2c-tiny-usb clone)
  • versaloon - JTAG stuff
  • DirtyJTAG - JTAG stuff
• RP2040 / RPi Pico
  • rp2040-i2c-interface - i2c-tiny-usb interface
• pico-usb-io-board - general purpose USB to SPI/I2C/ADC/GPIO interface

Informatic

        // This ClusterRole is bound to all humans that log in via prodaccess/prodvider/SSO.
        // It should allow viewing of non-sensitive data for debugability and openness.
        crViewer: kube.ClusterRole("system:viewer") {
            rules: [
                {
                    apiGroups: [""],
                    resources: [
                        "nodes",
                        "namespaces",
                        "pods",

Informatic

#!/bin/sh

# Directory to store overlays in (one directory structure is created per overlay configured down below)
OVERLAY_BASE=/var/lib/webosbrew/customca

overlay() {
        set -e
        overlay_id="$(echo $1 | sed 's;/;__;g')"
        unset TARGET SOURCE FSTYPE OPTIONS
        eval $(findmnt -P $1)

Informatic

#!/bin/bash

set -e

# Set route_localnet = 1 on all interfaces so that ssl can use "localhost" as
# destination
sysctl -w net.ipv4.conf.default.route_localnet=1
sysctl -w net.ipv4.conf.all.route_localnet=1

# DROP martian packets as they would have been if route_localnet was zero

Informatic

Advanced Recursive Diffing™

Ever needed to diff two trees of files, while doing some preprocessing on modified files? Well - we've got a solution for you. Or rather... our long friend git has.

Turns out it's perfectly legal to just use git diff --no-index on directories outside of (any) git repository. With that, we can (ab-)use built in git diff per-path/extension preprocessing feature.

Informatic

#!/bin/sh

# Directory to store overlays in (one directory structure is created per overlay configured down below)
OVERLAY_BASE=/home/root/overlays

overlay() {
        set -e
        overlay_id="$(echo $1 | sed 's;/;__;g')"
        unset TARGET SOURCE FSTYPE OPTIONS
        eval $(findmnt -P $1)