Monday, October 16, 2017

Some notes on the KRACK attack

This is my interpretation of the KRACK attacks paper that describes a way of decrypting encrypted WiFi traffic with an active attack.

tl;dr: Wow. Everyone needs to be afraid. (Well, worried -- not panicked.) It means in practice, attackers can decrypt a lot of wifi traffic, with varying levels of difficulty depending on your precise network setup. My post last July about the DEF CON network being safe was in error.

Wednesday, October 11, 2017

"Responsible encryption" fallacies

Deputy Attorney General Rod Rosenstein gave a speech recently calling for "Responsible Encryption" (aka. "Crypto Backdoors"). It's full of dangerous ideas that need to be debunked.

Sunday, October 01, 2017

Microcell through a mobile hotspot

I accidentally acquired a tree farm 20 minutes outside of town. For utilities, it gets electricity and basic phone. It doesn't get water, sewer, cable, or DSL (i.e. no Internet). Also, it doesn't really get cell phone service. While you can get SMS messages up there, you usually can't get a call connected, or hold a conversation if it does.

We have found a solution -- an evil solution. We connect an AT&T "Microcell", which provides home cell phone service through your Internet connection, to an AT&T Mobile Hotspot, which provides an Internet connection through your cell phone service.

Wednesday, September 27, 2017

Browser hacking for 280 character tweets

Twitter has raised the limit to 280 characters for a select number of people. However, they left open a hole, allowing anybody to make large tweets with a little bit of hacking. The hacking skills needed are basic hacking skills, which I thought I'd write up in a blog post.

Tuesday, September 26, 2017

5 years with home NAS/RAID

I have lots of data-sets (packet-caps, internet-scans), so I need a large RAID system to hole it all. As I described in 2012, I bought a home "NAS" system. I thought I'd give the 5 year perspective.


Reliability. I had two drives fail, which is about to be expected. Buying a new drive, swapping it in, and rebuilding the RAID went painless, though that's because I used RAID6 (two drive redundancy). RAID5 (one drive redundancy) is for chumps.

Speed. I've been unhappy with the speed, but there's not much I can do about it. Mechanical drives access times are slow, and I don't see any way of fixing that.

Cost. It's been $3000 over 5 years (including the two replacement drives). That comes out to $50/month. Amazon's "Glacier" service is $108/month. Since we all have the same hardware costs, it's unlikely that any online cloud storage can do better than doing it yourself.

Moore's Law. For the same price as I spent 5 years ago, I can now get three times the storage, including faster processors in the NAS box. From that perspective, I've only spent $33/month on storage, as the remaining third still has value.

Ease-of-use: The reason to go with a NAS is ease-of-use, so I don't have to mess with it. Yes, I'm a Linux sysadmin, but I have more than enough Linux boxen needing my attention. The NAS has been extremely easy to use, even dealing with the two disk failures.

Battery backup. The cheap $50 CyberPower UPS I bought never worked well and completely failed recently, so I've ordered a $150 APC unit to replace it.

Vendor. I chose Synology, and have no reason to complain. Of course they've had security vulnerabilities, but then, so have all their competition.

DLNA. This is a standard for streaming music among home devices. It never worked well. I suspect partly it's Synology's fault that they can't transcode well. I suspect it's also the apps I tried on the iPad which have obvious problems. I end up streaming to the iPad by simply using the SMB protocol to serve files rather than a video protocol.

Consumer vs. enterprise drives. I chose consumer rather than enterprise drives. I think this is always the best choice (RAID means inexpensive drives). But very smart people with experience in recovering data disagree with me.

If you are in the market. If you are building your own NAS, get a 4 or 5 bay device and RAID6. Two-drive redundancy is really important.



Friday, September 15, 2017

People can't read (Equifax edition)

One of these days I'm going to write a guide for journalists reporting on the cyber. One of the items I'd stress is that they often fail to read the text of what is being said, but instead read some sort of subtext that wasn't explicitly said. This is valid sometimes -- as the subtext is what the writer intended all along, even if they didn't explicitly write it. Other times, though the imagined subtext is not what the writer intended at all.

Monday, September 04, 2017

State of MAC address randomization

tldr: I went to DragonCon, a conference of 85,000 people, so sniff WiFi packets and test how many phones now uses MAC address randomization. Almost all iPhones nowadays do, but it seems only a third of Android phones do.