The Singleton Anti-Pattern

In programming, the whole idea is to avoid re-inventing the wheel, and re-use as much as possible. Some clever coders discovered that there were some mechanism that were used over and over again. For example, the “producer/consumer” mechanism, whereby one or more threads are “producers” and one or more threads are “consumers”. Instead of coders figuring out how to do this properly over and over again, a group of people decided to write a book that described how to solve some of these problems. “Design Patterns: Elements of Reusable Object-Oriented Software” they called it. In the business, the authors became known as the “Gang of Four”.

One of the patterns they described is a “Singleton“: A singleton is essentially a global object, that is instantiated when needed. The idea being that the user doesn’t need to know when, or how, the underlying object is created/destroyed, they can just use it, and all parts of the code then shares the same object. Isn’t that cool. It’s like global variables were suddenly being endorsed in a book, and by some clever people too!!

There are cases (rare, constrained) where a global variable makes sense; it makes sense when the physical properties that the software is trying to model, matches with a single object. E.g. a singular file on a disk or a specific camera in a network. It’s perfectly appropriate to model these objects as global, because there truly is only one of them.

Let’s consider a log mechanism. There may be several things that are logging data, but if all that data goes into just one file, then it’s OK to use a singleton for the file, but certainly not for the log abstractions. If there are three or four different modules that are all logging to the same file, then those modules must have their own logger instance, and the various instances that are made, can then write to the same file using the singleton.

A primitive class diagram could look like this:

             Module A -> Log A 
Parent  ->                        -> Singleton File
             Module B -> Log B

When you are acutely aware of this composition, you should eventually realize that each logger instance must add some identifier when it writes to the disk. Otherwise you get a log file that looks like this

File Open
File Open
File Write Failed
File Write Succeeded
File Close
File Close

What you want, in the file, is this

Module A: File Open
Module B: File Open
Module B: File Write Failed
Module A: File Write Succeeded
Module B: File Close
Module A: File Close

This appears to solve the problem; except there’s a caveat. Say someone writes an app that creates two instances of the parent module. Since the log file is a singleton, all log data is written to the same file. This, in turn, means that two instances of the parent will also write to the same file.

Consider this diagram

                              Module A -> Log A
                 Parent ->               
                              Module B -> Log B
Aggregator  ->                                       -> Singleton File
                              Module A -> Log A
                 Parent ->
                              Module B -> Log B

We are now in hell.

Module A: File Open
Module B: File Open
Module B: File Write Failed
Module A: File Open
Module B: File Write Failed
Module A: File Write Succeeded
Module B: File Close
Module A: File Write Succeeded
Module A: File Close

This issue is relatively easy to fix, and it’s still valid to have a requirement that there is just one log file (might be better to create one per parent, but that’s a matter of taste).

But what about issues where things like username, password, preferences etc. are stored in a singleton that contains “user info”. In that case, when the aggregator sets the username, the username change applies to ALL modules, regardless of where they reside in the aggregator tree. It’s therefore impossible for the aggregator to set a different username for Parent 1 and Parent 2. The aggregator, therefore, breaks.

Essentially, the coder might as well have said “let’s make the username a global variable”. 99% of all coders will object when they hear that (or “goto”). But 50% of all coders remain silent when the same pattern is described using the “singleton” moniker.

The morale of the story: don’t use singletons. Not even if you think you know what you are doing. Because if you think you know what you are doing, then you almost certainly do not.

 

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Worldwide Hack

Cameras have vulnerabilities, some easier to exploit than others. Unless you have some sort of mental defect, this is hardly news. This old fart wrote about it in 2013/2014, but it still affects a lot of people..

If you’re a bit slow in the head, you might want to take your hard earned cash, and give it to some sociopathic megalomaniac who thinks he’s the savior of the world, and feel helpless and vulnerable as you cower under the threat of the “big unknown”.

A recent hyped headlines exclaims:

“WORLDWIDE HACK”

But, you know, with this new-fangled internet, it’s pretty easy to do something “worldwide”; any script kiddie in their mother’s basement can hit every single IP that is exposed to the internet if they want. “Worldwide” don’t mean diddly squat these days. Unless you’re living in the 80’s, desperately trying to get your damn VCR fixed, so you can watch those old tapes you kept.

Now, Cameras, NVRs and DVRs with shitty security, straight to the internet? Bad fucking idea. Doesn’t mean that people don’t do it. Like drinking 2 gallons of Coke and wolfing down junk food for lunch and dinner is a bad idea -yet millions of people (actually worldwide) do it.

So you can make an easy buck selling subscriptions that places the blame squarely on the coke and pizza for the obesity epidemic. After all, who doesn’t like to be absolved of their sins, and pointing the finger at everyone else.  “The magazine says I am not to blame”, and then you can continue your gula uninhibited.

A wise person would not expect Coke or Papa Johns to spend millions of dollars showing the bad effects of poor dietary choices. They’ll continue to show fit girls and boys enjoying a coke and pizza responsibly, but the bulk of their income is certainly not derived from people with a BMI < 20.

While I understand the desire to believe that “easy” equates “correct”, it never ceases to amaze me that people don’t take any precautions. Maybe my mistake is that I am underestimating how gullible people really are (and my sociopath nemesis isn’t).

While this big, nasty, “worldwide” attack is taking place, I still haven’t seen anyone hack my trusty old Hikvision camera sitting here on my desk… must be a coincidence that I wasn’t hit.

Are You Diffident?

It always amused me when someone says “my personal opinion”. I find it strange, because the “personal” part is superflous. If the person says “my opinion is that red is a nice color”, I assume that the person means what he says: To him, red is a nice color.

If I then give him a red shirt, he says “don’t like it, I hate red”, I would assume some mental illness at play…

“but.. but.. you just said…”, I stutter

“yes, but that was not my personal opinion”

“WAT?”,

puzzled

Opinions don’t have to be personal, sometimes you’ll read “it is the opinion of the court” and things of that nature. But in those cases, it’s pretty clear that it is not the opinion of the person saying the words, that we are talking about. It would be exceedingly weird if the court clerk said “in my opinion, the accused is guilty”.

There are people with mental issues that have trouble with this concept. It is known as Dependant Personality Disorder. It basically means that you can’t have an opinion on anything, you constantly have to ask someone else what their opinion is and then act in accordance with that.

Someone who is deeply narcissistic (borderline?) might assume that everyone in the world, besides themselves, ought to suffer from DPD, and become upset and frustrated when people have opinions that do not align with what they are preaching.

The truth is that finding factual, verifiable information about IP cameras and software is getting easier every day (and this is an old video). Like most people, I don’t much care for what salespeople are saying if it can’t be verified or measured. If the salesperson can provide the raw data, I’ll take it. I will form my own opinion based on what I see. I don’t need some Gríma Wormtongue whispering into my ear.

grima2

With the commoditization of IP cameras, increasing demand for true interoperability we’re getting to a point where facts are valuable, whereas opinions are not (yep, this blog is free!!!). In some cases though. arguments and opinions may be based, not on unbiased interpretation of facts, but instead it is shaped by grudges and anger.

If you are paying for facts, you definitely should demand full disclosure, or if you’re not, you need to ask yourself, am I reading verifiable facts, or just bullshit? You might ask: Are manufacturers paying (directly, or indirectly) the one stating opinions about either the manufacturers products, or the products of the manufacturer’s competitors? If you’re being lied to in the full disclosure, you might be lied to elsewhere.

 

 

I Am Myself

Well, well, well…

This weekend I posted a piece on IPVMs crusade against Hikvision which seemed to suggest a lack of technical comprehension and perhaps – general assholery.

1 minute after posting, I receive a visit from Ghana. I have also had visitors from Mali and other nations in Africa that seemingly have a keen interest in what I have to say. Another option is that someone thinks they need to use Tor (or some other anonymizing browser) to read my blog.

This morning, I woke up to an email, asking me to ensure that the folks from some obscure blog understands that this blog is in no way, shape or form affiliated with OnSSI. A strange coincidence that writing about a sensationalist blog fucking things up, triggers a request for clarification about the independence of this one.

So let me make that absolutely clear, so that even sensationalist bloggers running fake universities, and his “associates” can understand it.

This blog, has nothing to do with OnSSI.

While I have written specifically about the mobile app OnSSI released a while ago, other people in the software development industry (not IP video), have the exact same experience. Next generation apps face an uphill battle as loyal users of the old app discover that things may have changed, and they are much more likely to post a very negative “review”, than people who will eventually benefit from the improvements. Since posts that are anchored in real experiences are dangerous to my livelihood (the blogger is using them as a vector to try and shut me down), I will remove that type of content from the blog (but I am confident that the Ghanaian visitor made a copy before reaching out to protect the innocent, so just ask him for a copy).

So, just to be clear, what you read in these posts, is the opinions and thoughts of the person Morten Tor Nielsen. I submit ideas and thoughts that are founded in a general understanding of the world as I see it.

I suppose that if you are consumed with deranged ideas about infiltration of corner shops and jiffy-lubes by the Chinese government, and your every living hour is spent on thinking about how to attract more subscribers to your rumour-mill, then this might be hard to fathom, but I work on a wide range of things (including overhauling my old Suzuki Bandit 600), and so among the exposure of incompetent asshats (from my humble computer here in Copenhagen), jot about a lot of things.

If you follow my blog, you’ll know that I have been working on micro-PC‘s, I have set up Axis cameras to provide health state information, I have done a lot of GPU work (yes, for OnSSI) and many other things. I have called out BS here, and here, and here  and many other places. I have mused over how companies can improve and what danger signs to look for. I have critiqued buzz-word-driven development (as a response to VR goggles being passed out at a convention). The list goes on…

You have to be senile, demented or sociopathic to think that this blog would somehow reflect the “thoughts” of a company. So if you suffer from any of the 3, and that’s the reason you contact OnSSI rather than writing a comment refuting claims, then you’re excused.

If not, you’re just a sad, over-extended sphincter.

But I think you (and everyone else) know that already.

In Defence of Hikvision

Look at this nonsense!

Brian Karas reported on March 2 that he was hearing from multiple Hikvision security camera and DVR users who suddenly were locked out of their devices and had new “system” user accounts added without their permission.

Karas said the devices in question all were set up to be remotely accessible over the Internet, and were running with the default credentials (12345). Karas noted that there don’t appear to be any Hikvision devices sought out by the Mirai worm — the now open-source malware that is being used to enslave IoT devices in a botnet for launching crippling online attacks (in contrast, Dahua’s products are hugely represented in the list of systems being sought out by the Mirai worm.)

[I cut out some text from here (I’ll tell you why)]

According to Karas, Hikvision has not acknowledged an unpatched backdoor or any other equivalent weakness in its product. But on Mar. 2, the company issued a reminder to its integrator partners about the need to be updated to the latest firmware.

OK, so Brian hears that people who a) expose their IP cameras directly to the internet, and b) are using default admin credentials “suddenly were locked out of their devices”. My God, what kind of evil genius hacker is behind this, and there were new “system” user accounts!!?!

This must be the Chinese government’s work. Only a government organisation would be able to crack into IP devices with default passwords that are directly exposed to the internet.

When people got their shit “hacked”…. actually, let’s not call it hacked. Someone logged in, as admin, and changed things, so, not hacking. Someone had done something similar to mirai (which will take any script kiddie 30 minutes to write up, but Karas and Krebs pretend to not understand that). Hikvision sees this, and then reminds people to update their firmware, and as the new firmware does not allow default passwords (as far as I can tell), it seems prudent advice, and what you ought to do.

Krebs seems to want to play a part in all this “dangerous Hikvision camera” bullshit, so instead of posting a meaningful timeline, he spices things up, and injects this little tidbit (which I removed above to ensure a comprehensible timeline).

In addition, a programmer who has long written and distributed custom firmware for Hikvision devices claims he’s found a backdoor in “many popular Hikvision products that makes it possible to gain full admin access to the device,” wrote the user “Montecrypto” on the IoT forum IPcamtalk on Mar. 5. “Hikvision gets two weeks to come forward, acknowledge, and explain why the backdoor is there and when it is going to be removed. I sent them an email. If nothing changes, I will publish all details on March 20th, along with the firmware that disables the backdoor.”

OK, so on the 2nd the n00bs at IPVM and their subscribers are “hacked” by a genius hacker, who is able to guess the password and add new accounts, and then on the 5th, a guy who re-compiles the hikvision firmware discovers a vulnerability. In fact, he tells John Honovich that Hikvision has been very responsive in fixing the issue!! This seems to get lost somewhere between the sensationalist blogs (I think, because I am banned from IPVM).

How the hell do you make a connection between morons who exposes their cameras with default admin credentials, and someone discovering a bug in the validation of a reset packet (I guess that is the vulnerability, because I don’t know the details). You make that connection, if you think it will bring in more subscribers, and by extension, more filthy lucre.

Full disclosure: I am not paid in any way shape or form by Hikvision or any camera manufacturer for that matter. I receive no payment from this blog either, the ads you might see are put there by wordpress that hosts the blog, as compensation for hosting and traffic cost (and profit I guess), but I receive exactly $0.

Hikvision Feeds a Troll

It’s possible to turn someone towards the light, and eventually lead them to salvation.

A prominent member of the Westboro Baptist Church, Megan Phelps-Roper made a TED speech about it. What saved Megan was not someone yelling in her face. She was conditioned to expect exactly that from the misguided heathens of the world. Instead, someone approached her with curiosity, warmth and civility and lead her out of the congregations grasp. The “enemy” is rarely a mindless drone out to do evil. Although, our leaders would prefer we see things that way.

Our industry has a variant of the WBC, and Hikvision has chosen a different approach to liberate the members of the sect.

a site that has always trafficked in nefarious insults and innuendo. Hiding behind a keyboard, the tabloid’s staff takes unfounded potshots at our entire industry, bullying one company at a time.

and

Instead, he chooses to distract manufacturers with his pursuit of financial gain and efforts to fulfill his delusions of grandeur.

The problem with this sort of message is that the hardcore members are expecting exactly this sort of rhetoric, thereby further entrenching them in their beliefs. Ultimately the blogger will surely capitalize of the increased attention being paid. I thought it was common knowledge that trolls have an insatiable appetite for the kind of copy Hikvision just released.

jh
More please!

Members of the sect can attend a “university” (not at all like this one) and even make the “dean’s list“. This is impressive stuff, and these people are not going to be swayed by a manufacturer having a breakdown in their public relations department. Furthermore, I suspect Hikvision has several active subscriptions, thereby directly funding the site.

I think Hikvision is correct in calling it cyber-bullying. It has all the traits of schoolyard terrorism; the ring-leader points out an arbitrary enemy, then manipulates the enemy to react. Steps in to protect the flock from the aggressor. If it gets too hot, the ring-leader can count on his 3 or 4 lackeys to do the dirty work.

In this case, the sin of the “enemy” is that the company is partially owned by the Chinese government. Therefore, every vulnerability found in a Hikvision camera is proof positive that the Chinese government is spying on us. I don’t buy that. Governments don’t have to own a company to assert influence over it.

You might remember Stuxnet a vulnerability in SCADA equipment was exploitable by governments and for-lulz hackers alike. Vulnerabilities will continue to exists as long a fallible humans write the code. As long as fallible humans install and (fail to) maintain the equipment we will continue to see flaws and problems. Unfortunately, a lot of companies have deployed small time-bombs with terrible security in place, not just Hikvision.

When I was in the army, we had padlocks on our lockers. On the first day, we were instructed to get a hair-cut “to not look like faggots” (I kid you not, that’s what he said), and then to make sure our lockers were safely locked. The reasoning (for locking up) is that you can’t really trust anyone, and giving the bad apples the opportunity to steal was almost as bad as the guy stealing. At a company I worked for a long time ago (starts with an M), someone shat on the toilet seat in the offices restroom. Someone we had lunch with, talked about code, movies, politics and music with, went to the bathroom, and shat on the seat, leaving it there for some poor soul to find.

Same thing goes for your IP camera. Sticking that thing on the internet, REGARDLESS of manufacturer ownership is like leaving your locker unlocked. You are tempting the swines of the world to mess around, and when they do, we all lose.

madness

Listening to Customers

In 2011, BlackBerry peaked with a little more than 50 million devices sold. The trajectory had an impressive ~50% CAGR from 2007 where the sales were around 10 million devices. I am sure the board and chiefs were pleased and expected this trend to continue. One might expect that ~250 million devices were to be sold in 2016 if the CAGR could be sustained. Even linear growth would be fairly impressive.

Today, in 2017, BlackBerry commands a somewhat unimpressive 0.0% of the smartphone market.

There was also Nokia. The Finnish toilet-paper manufacturer pretty much shared the market with Ericsson in Scandinavia and was incredibly popular in many other regions. If I recall correctly, they sold more devices than any other manufacturer in the world. But they were the McDonalds of mobile phones: Cheap and simple (nothing wrong with that per se). They did have some premium phones, but perhaps they were just too expensive, too clumsy or maybe too nerdy?

ngage
Talking on a Nokia N-Gage phone

Nokia cleverly tricked Microsoft into buying their phone business, and soon after the Microsoft gave up on that too (having been a contender in the early years with Windows CE/Mobile).

I am confident that BlackBerry was “listening to their customers”. But perhaps they didn’t listen to the market. Every single customer at BlackBerry would state that they preferred the physical keyboard and the naive UI that BlackBerry offered. So why do things differently? Listen to your customers!

If BlackBerry was a consulting agency, then sure, do whatever the customer asks you to. If you’re selling hot-dogs, and the customer asks for more sauerkraut, then add more sauerkraut, even if it seems revolting to you. But BlackBerry is not selling hotdogs or tailoring each device to each customer. They are making a commodity that goes in a box and is pulled off a shelf by someone in a nice shirt.

As the marginally attached customers are exposed to better choices (for them), they will opt for those, and in time, as the user base dwindles, you’re left with “fans”. Fans love the way you do things, but unless your fan base is growing, you’re faced with the very challenging task of adding things your fans may not like. Employees that may be prostrate bowed but not believing, will leave and eventually you’ll have a group of flat-earth preachers evangelizing to their dwindling flock.

It might work as a small, cooky company that makes an outsider device, but it sure cannot sustain the amount of junk that you tag on over the years. Eventually that junk will drag the company under.

Or, perhaps BlackBerry was a popular hotdog stand, in a town where people just lost the appetite for hotdogs and had a craving for juicy burgers and pizza (or strange hotdogs)