Author Archive for

18
Aug
15

Using a LG TV Wi-Fi adapter on a PC

Updated 2016-01-04: There’s a newer Netgear driver that works on Windows 10, as well as a way to force installation without Test Mode. Ignore the comments about IRQL_UNEXPECTED_VALUE blue screens, those relate to the old Belkin driver.

Some old LG TV models did not have integrated Wi-Fi, instead requiring the AN-WF100 USB Wi-Fi adapter. This adapter has a standard Broadcom chip, and can be used on a Windows PC with the steps below:

  1. Download the Netgear WNDA3100v2 driver.
  2. Install the driver normally. A Netgear Genie screen will ask you to plug in the adapter – close it by right-clicking its taskbar button and clicking Close.
  3. Optionally disable the “WNDA3100v2.exe” startup entry using AutoRuns to stop Netgear Genie from bothering you every startup.
  4. Connect the LG adapter to your PC. It will be detected as an unknown “Remote Download Wireless Adapter” device.
  5. Open Device Manager, right-click the unknown “Remote Download Wireless Adapter” device, select “Update Driver…”, choose to browse for driver software, then to pick from a list of device drivers.
  6. Select the “Network adapters” category, wait for it to load, scroll down to “Netgear” and select the “Netgear WNDA3100v2 N600 Wireless Dual Band USB Adapter”.
  7. Ignore the warning about driver compatibility.

After following these steps, Wi-Fi should be working. If it doesn’t, you have the wrong adapter, or you’ve done something wrong.

2016-01-04_23-16-16

01
Jan
15

Notes on Red Star OS 3.0

Updated 2016-01-04: A year after Red Star 3.0 surfaced on 31C3, 32C3 held a talk on its internals. The talk documents the official root method and some malicious components; I have updated this post accordingly.

The latest version of North Korea’s custom Linux distribution, Red Star OS – that one with the OS X style interface – has leaked onto the internet. While the individual who talked about technology in North Korea on the 31C3 conference said he didn’t see anybody using Red Star seriously, it’s a rather interesting distribution to check out.

LLBMKWg

 

Installation

The Korean installer is quite easy to go through blind. All you need to watch out for is the network configuration, which is not set to DHCP by default. Some extras (including compilers and a LAMP stack) are available through the Customize dialog right before it starts the actual installation.

The installer (a customized version of Fedora’s Anaconda) can run in English with a modification to the ISO: in /isolinux/isolinux.cfg, replace lang=ko with lang=en on the kernel parameters. Some minor parts of the UI are images which weren’t translated. The final system will still be in Korean, but we’ll fix that later.

Red Star 3-2015-01-01-20-47-52

 

Obtaining root

The root user is disabled by default on Red Star. You can enable it with the /usr/sbin/rootsetting command, although I cannot verify how it works.

My old root-shell RPM is still available here for reference.

 

English

Like the installer, the system can run in English, and the included apps have English translations as well. Run the following commands as root, reboot, and the system will be in English:

sed -i 's/ko_KP/en_US/g' /etc/sysconfig/i18n
sed -i 's/ko_KP/en_US/g' /usr/share/config/kdeglobals

Thanks to davidiwharper on OSNews for the sed command.

Red Star 3-2015-01-02-13-50-04

 

Fixing internet

For some reason, Red Star’s iptables is set to only allow outgoing connections to certain ports. That doesn’t include DNS (North Korea’s intranet uses IP addresses only), so you can’t get a proper internet connection on Red Star. To fix that, run this command as root to clear Red Star’s default iptables rules, and reboot:

rm /etc/sysconfig/iptables

The included “Naenara Browser” is Firefox 3.5, and despite being set to browse on the North Korean intranet, it works just fine on the internet. Its language can be changed to English by disabling the Korean language pack (thanks Chocohead): go to the second-to-last menu, select the third option, go to the fourth tab, select the “(ko-KP)” add-on, click the first button to disable it, and click the button on the yellow bar to restart the browser.

Red Star 3-2015-01-02-22-23-36

 

Dubious components

As highlighted in the 32C3 follow-up talk, Red Star contains several shady components, including but not limited to a file watermarking service and a supposed “virus scanner”. The speakers provided instructions on how to disable these components.

 

Other things

  • The system seems to be dated October 2012. UPDATE: Packages as new as 2013 are in the system.
  • There appears to be a system file modification detector, which warns about modified system files when you log in. Running the installer in English was enough for it to complain about the kernel files, at least for me. To disable it, run this command as root: rm /usr/share/autostart/intcheck_kde.desktop
    • The 32C3 talk also mentions a similar service which automatically reboots the system if files related to the aforementioned malicious components are modified.
  • The disc includes a Windows executable named install.exe, which displays a dialog (actually an image lifted from the EXE resources) with two buttons. The first one displays an error, which probably tells you to boot from the DVD, and the second one closes the dialog.
    XP Pro-2015-01-08-20-20-29XP Pro-2015-01-08-20-20-55
  • Press Esc on the boot splash for verbose boot.
  • In several places, you’ll see English or South Korean locales replaced to accommodate the North Korean locales.
  • There is a surprising lack of Engrish in the included apps. One theory is that all English text was taken straight out of OS X.
  • The “Crosswin” Windows compatibility layer is a wrapper around Wine 1.2.2.
29
Nov
14

On the quality of decompiled code

I have a piece of advice on the Minecraft code that I always wanted to say but never had the opportunity/context to: The decompiled code, as produced by MCP, jd-gui or any other decompiler, does not reflect Mojang’s actual coding.

I remember the days when people complained “Notch y u no use case!!!111” when he actually did. Garry from GMod made a blog post on that, but it was lost to time.

What happens is that, since they’re functionally equal, the Java compiler produces the same bytecode for a case as it would for a regular if-else. With that, a decompiler sees any case statement as a simple if-else, because that’s how it was compiled.

Decompilers are never 100% accurate. When MCP switched from jad to Fernflower, the amount of patches required for the Minecraft code to compile may have been cut down massively, but it will never reach the same level as Mojang’s original code.

Sidebar: I still remember the days I fixed trivial MiscPeripherals bugs by poking at the bytecode with JBE (and oftentimes fail to), since a full round of “start Eclipse -> fix bug -> recompile -> reobfuscate -> test in Minecraft” took 15-20 minutes on my aging PC…

15
Jun
14

I blog.

When you feel like you’re stacking up on notes-to-self on your mind, what’s the first thing you should do? Start a blog to put those on. And that’s what I did.

Apparently I created this blog in 2010, but it was more for personal matters than this, so I started over while keeping the same theme (which still looks cool) and domain.

Don’t expect regular or particularly long posts.

15
Jun
14

Linux, Intel HDA, VIA codec and headphones

Yesterday, I finally bothered to get Debian 7 set up on my real machine (with Intel HDA and a VIA VT1705 codec), but I ran into an issue where headphone sensing doesn’t work: audio comes out from the back jack if I don’t have anything plugged to the front jack, but if I do have something plugged to the front jack, neither of them will work.

I tried looking for a solution, but they all relate to systems with Realtek codecs. Here’s what solved it on mine:

  1. Start alsamixer
  2. Scroll all the way to the right
  3. Select the “Smart 5.1” option
  4. Hit . (period) to unmute it

hda_alsamixer

As odd of a name “Smart 5.1” is, enabling it will make headphone sensing work.