Special Edition is the blog for security testing business SE Labs. It explains how we test security products, reports on the internet threats we find and provides security tips for businesses, other organisations and home users.

Monday, 21 August 2017

The Government Encryption Enigma

Is Amber Rudd right about encryption? Jon Thompson isn't so sure.

UK Home Secretary Amber Rudd recently claimed in an article that "real people" prefer ease of use to unbreakable security when online. She was met immediately by outrage from industry pundits, but does she have a point?

Though paywalled, as reported elsewhere, Rudd asks in her article, "Who uses WhatsApp because it is end-to-end encrypted, rather than because it is an incredibly user-friendly and cheap way of staying in touch with friends and family?"

Rudd name-checked Khalid Masood, who used WhatsApp minutes before he drove a van into pedestrians on Westminster Bridge killing three, and then fatally stabbed a police officer outside Parliament before being shot dead. However, Masood was not part of any MI5 investigation. In fact, a week after the attack, police had to appeal for information about him. His final WhatsApp message seems to have been the first sign that he was about to strike. The recipient was entirely innocent, and knew nothing of his murderous intentions.

There are plenty of other atrocities that were planned in part via social media apps. The attacks on Paris in December 2015, and the Stockholm lorry attack to name but two. In the UK the new UK Investigatory Powers Act 2016 (IPA), which caused so much fuss last year, can compel vendors to decrypt. So, why not just use that? The answer is somewhat complicated.

The IPA makes provision for Communications Service Providers to be served with a notice that they must remove encryption from messages to assist in the execution of an interception warrant. Apart from Providers needing access to private decryption keys, reports suggest that any move to enforce this measure would meet stiff opposition, and may not even be enforceable.

Many of the most popular secure messaging apps use the Signal Protocol, developed by Open Whisper Systems. This is a non-profit organisation and lies outside the UK's jurisdiction, so its compliance would be difficult to obtain, even if the companies using the protocol agreed to re-engineer their platforms to include backdoors, or to lower encryption standards. There are also plenty of other issues to be resolved if Rudd is to get her way.

If the government mandates weaker encryption for messaging apps in the UK, then companies will face difficult business choices and technological challenges. It boils down to a choice: they could weaken their encryption globally, or they could just weaken encryption in the UK. But what happens
if you send a secure message from outside the UK to someone inside the country? Can the UK authorities read it? Can the recipient, using a lower encryption standard, decrypt it? How would international business communications work if the UK office doesn't use the same encryption standard as a foreign parent company?

This isn’t the first time the UK government has attempted to find an answer to the problem of encryption. Back in January 2015, the then-Prime Minister David Cameron gave a speech in which he said there should be no means of communication "which we cannot read". He was roundly criticised as "technologically illiterate" by opposition parties, and later clarified his views, saying he didn’t want to ban encryption, just have the ability to read anyone's encrypted communications.

Authoritative voices have since waded into the argument. Lord Evans, the former head of MI5, has recently spoken out about the problems posed by strong encryption: “It’s very important that we should be seen and be a country in which people can operate securely – that’s important for our commercial interests as well as our security interests, so encryption in that context is very positive.”

Besides, if the government can decrypt all messages in the UK, won’t genuine terrorists simply set up their own "dark" services? Ten seconds on Google Search shows plenty of open source, secure chat packages they could use. If such groups are as technologically advanced as we're led to believe, then it should be simple for them, and terrifying for the rest of us. Wouldn’t it be better to keep such groups using mainstream apps and quietly develop better tools for tracking them via their metadata?

Rudd's argument that "real people" want ease of use over strong encryption implies that secure apps are in some way difficult to set up and require effort to maintain. The opposite is plainly true, as anyone who's ever 'butt dialled' with their mobile phone can tell you.

Rudd's argument also plays into the idea that if you have nothing to hide you have nothing to fear. While writing this piece, I accessed several dozen online information sources, from mainstream news reports of terrorist outrages to super paranoid guides for setting up secure chat services. I accessed many of these sources multiple times. I didn’t access any extremist material, but my browsing history shows a clear and persistent interest in recent atrocities perpetrated on UK soil, secure chat methods, MI5 and GCHQ surveillance methods, encryption algorithms, and so on. Joining the dots to arrive at the wrong conclusion would be a grave mistake, and yet without the wider context of this blog piece to explain myself, how would authorities know I'm not planning to be the next Khalid Masood or Darren Osborne? The answer lies in developing better tools that gather more context than just what apps you use.

Friday, 4 August 2017

Quantum Inside?

Is this the dawn of the quantum computer age? Jon Thompson investigates.

Scientists are creating quantum computers capable of cracking the most fiendish encryption in the blink of an eye. Potentially hostile foreign powers are building a secure quantum internet that automatically defeats all eavesdropping attempts.

Single computers far exceeding the power of a hundred supercomputers are within humanity's grasp. 

Are these stories true, as headlines regularly claim? The answer is increasingly yes, and it's to China we must look for much current progress.

The Quantum Internet
Let's begin with the uncrackable "quantum internet". Sending messages using the properties of the subatomic world has been possible for years; it's considered the "gold standard" of secure communications. Chinese scientists recently set a new distance record for sending information using quantum techniques when they transmitted data 1,200Km to a special satellite. What's more, China is implementing a quantum networking infrastructure.

QuantumCTek recently announced it is to deploy a network for government and military employees in the Chinese city of Jinan, secured using quantum key distribution. Users will send messages encrypted by traditional means, with a second "quantum" channel distributing the associated decryption keys. Reading the keys destroys the delicate state of the photons that carry them, so it can only be done once by the recipient, otherwise the message cannot be decrypted and the presence of an eavesdropper is instantly apparent.

The geopolitical implications of networks no foreign power can secretly tap are potentially immense. What's scarier is quantum computers cracking current encryption in seconds. What’s the truth here?

Encryption Under threat
Popular asymmetric encryption schemes, such as RSA, elliptic curve and SSL, are under threat from quantum computing. In fact, after mandating elliptic curve encryption for many years, the NSA recently declared it potentially obsolete due to the coming quantum computing revolution.

Asymmetric encryption algorithms use prime factors of massive numbers as the basis for their security. It takes a supercomputer far too long to find the right factors to be useful, but it's thought to be easy for a quantum algorithm called Shor's Algorithm.

For today's strong symmetric encryption, such as AES and Blowfish, which use the same key to encrypt and decrypt, the news is currently a little better. It's thought that initially, quantum computers will have a harder time cracking these, only really halving the time required by conventional hardware. So, if you're using AES with a 256-bit key, in future it'll be as secure as a 128-bit key.

A Quantum Leap
How far are we from quantum computers making the leap from flaky lab experiments to full production? The answer depends on the problem you want to solve, because not all quantum computers are the same. In fact, according to IBM, they fall into three classes.

The least powerful are quantum annealers. These are available now in the form of machines from Canada's D-Wave. They have roughly the same power as a traditional computer but are especially good at solving optimisation problems in exquisite detail.  Airbus is already using this ability to increase the efficiency of wing aerodynamics.

More powerful are analogue quantum computers. These are much more difficult to build, and IBM thinks they're about five years away. They will be the first class of quantum computers to exceed the power of conventional machines. Again, they won’t run programs as we think of them, but instead will simulate incredibly complex interactions, such as those found in life sciences, chemistry and materials science.

The most powerful machines to come are universal quantum computers, which is what most people think of when discussing quantum computers. These could be a decade or more away, but they're coming, and will be exponentially more powerful than today's fastest supercomputers. They will run programs as we understand them, including Shor's Algorithm, and will be capable of cracking encryption with ease. While they're being developed, so are the programs they'll run. The current list stands at about 50 specialised but immensely powerful algorithms. Luckily, there are extremely complex engineering problems to overcome before this class of hardware becomes a reality.

Meanwhile, quantum computer announcements are coming thick and fast.

IBM has announced the existence of a very simple device it claims is the first step on the path to a universal quantum computer. Called IBM Q, there's a web portal for anyone to access and program it, though learning how and what you can do with such a device could take years.

Google is pursuing the quantum annealing approach. The company says it plans to demonstrate a reliable quantum chip before the end of 2017, and in doing so will assert something called "quantum supremacy", meaning that it can reliably complete specialised tasks faster than a conventional computer. Microsoft is also in on the action. Its approach is called StationQ, and the company been quietly researching quantum technologies for over a decade.

Our Universal Future
While there's still a long way to go, the presence of industry giants means there's no doubt that quantum computers are entering the mainstream, but it'll probably be the fruits of their computational power that we see first in everyday life rather than the hardware itself. So, solutions to currently difficult problems and improvements in the efficiency of everything from data transmission to batteries for electric cars could start appearing.

Life will really change when universal quantum computers finally become a reality. Be in no doubt that conventional encryption will one day be a thing of the past. Luckily, researchers are already working on so-called post-quantum encryption algorithms that these machines will find difficult to crack.

As well as understandable fears over privacy, and even the rise of quantum artificial intelligence, the future also holds miracles in medicine and other areas that are currently far from humanity's grasp. The tasks to which we put these strange machines remains entirely our own choice. Let's hope we choose wisely.