Linux FormatMay 2017的目錄

Jonni Bidwell I’d really like to get into making a Raspberry Pi-powered audio powerhouse, using something like the pisound interface available on Indiegogo. But then again I know nothing about making music, and my musical tastes are questionable, so I’ll probably just stick to getting Netflix working on Raspbian. Neil Bothwick I am using a couple of Raspberry Pis to build my own self driving car. There are still a few teething problems, mainly in avoiding collisions with the cat! I’ll spend more time on it once I’ve finished converting my secret underground bunker to use Pi power. Nate Drake I have a Pi Zero W winging its merry way to my PO box even as I write this. My first project is going to be to recreate the ‘Purple’…

“Cybersecurity is one of the hottest topics in IT right now. More specifically, a lot of attention has been given to the glaring talent shortfall. In a global survey of IT professionals conducted by Intel Security and the Center for Strategic and International Studies in 2016, 82% of respondents admitted to a lack of cybersecurity skills. Worryingly, one in four further reported that their organisations had lost proprietary data as a result of their cybersecurity skills gap. With a snowballing amount of business and personal information being hosted on the cloud, filling the gap in cybersecurity skills has become a task of unprecedented urgency. Did you know that there are seven classes of cyber attackers, all of whom have an arsenal of attacks at their disposal? In response to these…

Find and join a LUG Alpinux, le LUG de Savoie Meet on the 1st and 3rd Thursday of the month at the Maison des Associations de Chambéry. www.alpinux.org Bristol Hackspace Studio G11, 37 Philip Street, Bedminster, Bristol, UK, BS3 4EA. http://bristol.hackspace.org.uk Surrey and Hampshire Makerspace Open evenings Tues/Fri at the Boileroom in Guildford. www.shmakerspace.org Lancaster and Morecambe Makers Unit 5, Sharpes Mill, White Cross, Lancaster, Open Night on Wednesday evening 18:30 until late. www.lamm.space Hull Raspberry Jam Malet Lambert School, Hull. Every other month. See the Twitter account. https://twitter.com/hullraspjam Preston Hackspace 28A Good St, PR2 8UX. Open night is 2nd Monday of the month, 19:00. http://prestonhackspace.org.uk Huddersfield Raspberry Jam Meet every month at Huddersfield Library. Huddersfieldraspberryjam.co.uk North Kent Raspberry Pi User Group Every two weeks at Medway Makers, 12 Dunlin…

MQTT stands for Message Queue Telemetry Transport and it works as a lightweight messaging protocol for use on top of the TCP/IP protocol. MQTT is an ideal choice for working with devices that have limited network bandwidth, as it can even be used with a dial-up internet connection. The first version of MQTT was authored in 1999 by Andy Stanford-Clark and Arlen Nipper and since then it has been used in home automation projects, sensor networks and to control Christmas tree lights from across the world. As we mentioned at the start of the tutorial, MQTT is a machine-to-machine protocol that enables devices to publish and subscribe to ‘topics’ that are of interest. In our project we created a small network where one Publisher sent data to a Broker which…

Beware of an old web page that may be your first Google result, going by the URL: http://vlc-bluray.whoknowsmy.name. It has an old key file from early 2016: do notuse it! If you use this file, your Blu-ray success rate will drop from about seven out of ten to something like four out of ten – a mistake we found out the hard way! This link may still be included in a number of manuals and tutorials, so if you’ve written some older documentation yourself, please update the link. The correct link is: www.labdv.com/aacs If you visit this page, you will likely get a key database file from the last few days and infinitely more keys than the old 2016 file. Also included are links to further libraries and useful programs,…

“This program packs all those features into a tiny package.” Image editor AzPainter Version: 2.0.2 Web: http://bit.ly/2m2wQPN The hero of this review is a tiny program, the source code of which occupies only half of an old-fashioned 3.5” floppy disk, or as little as 750KB. Yet it poses a challenge to major image editors such as Gimpor Krita— the recognised and heavyweight Linux apps for graphic enthusiasts and artists. AzPainterwas written by a Japanese software engineer known as Azel for drawing bitmap illustrations. It implements an original UI layout optimised for efficient drawing workflow – as seen by the author, which is why it may take you few extra minutes to get used to the AzPainterinterface. The application features support for 16-bit colour images with transparency (RGBA), automatic brush size…

Our expert Nate Drake is a freelance technology journalist who specialises in cybersecurity and retro tech. Back in 440BC, the tyrant Histiaeus, knowing his messages were being intercepted, shaved the head of his most trusted slave (an oxymoron [sharp dull–Ed] if there ever was one) and tattooed a message to his vassal Aristagoras. Time was clearly abundant as the slave was allowed to wait until his hair regrew, then duly sent off with a harmless-looking letter in hand. He asked Aristagoras to shave his head and read the real message on arrival, which instructed the vassal to revolt against the Persians. If we overlook momentarily the fact that it would have been far easier to give the slave the secret message to deliver orally [not that trusted?–Ed], this is the…

The fact that you don’t need to meet with your contacts to send secret stego messages is both a strength and weakness. If an adversary were to discover your steg file they could replace it with one of their own containing false information in a bid to trap you or your contacts. For this reason, consider using the command line utility gpgto digitally sign any messages you send. This utility is traditionally used for encrypting data – files are encoded with a “public” key which you make available to everyone and decoded by a separate “private” key which never leaves your computer. The process however can work in reverse, whereby you encode a file with your private key. This offers no security in terms of reading data, as anyone in…

Deploying many virtual machines using the method we followed in this introduction would take a lot of time – time that could be better spent on other things. Luckily a lot of time can be saved by using templates. Templating a machine means you can deploy several machines quickly with minimal intervention. Happily, creating templates is a straightforward process. Right-click on the VM to template and you can either convert that machine to a clone (it becomes unavailable as a running VM) or clone to new machine. When using VM templates it is recommended that the administrator install and configure only those services and updates that are needed in order to create a solid base installation VM from which you can install additional individual requirements on a per server basis.…

1 Download JRE & TruPax Open Terminal and add the PPA for Java with sudo add-apt-repository ppa:webupd8team/ java. Next run sudo apt-get update then sudo apt-get install default-jre oracle-java8-installer. Head to http://coders lagoon.com to download TruPax for your machine. Right click the file, choose ‘Extract’, then use cd to navigate to its folder, eg, cd /home/bodhi/Downloads/TruPax9A. 2 Launch TruPax Run java -jar trupax.jar to launch TruPax. Choose your language (German or English are the choices). Click ‘Add Files’ or ‘Add Folder’ to select data for encryption. Click ‘Make Volume’ when you are ready to set a password. TruPax will ask you where to save the file and to set a name, such as kittens.hc. You can use any name that takes your fancy as an extension. 3 Mount in VeraCrypt…

Besides taking the pain and suffering out of Samba (and there can be a fair amount of pain once you start getting your user mappings and smb.confs in a twist), Webmincan also administer virtually all other aspects of your system. From cronjobs to software packages to log files to users, Webmincan respectively edit, install, peruse and ban these all from the comfort of a web browser. Previously we installed fail2banto protect our SSH server from bot logins, and you’ll find a module for controlling it in Webmin’s Networking section. Plus, you can configure the SSH daemon itself from the Servers section. However, all this convenience comes at a potential cost, namely that anyone who has access to our username, password and the Webminlogin page basically has entire control of our…

There is a vulnerability where a public subkey could be attached to another certificate whose owner could then claim to have signed a document. To prevent such a scenario occurring, GnuPG now checks that signing keys are cross-certified before verifying signatures. Cross certification requires that subkeys sign the primary key to prove their authenticity. These “back” or “binding” signatures are embedded within the self-certification signatures that GnuPG adds to the signing subkeys – you can’t see them with --list-sigs. Older versions of GnuPG or other OpenPGP applications may not have this feature and signing subkeys generated with these applications may lack the required binding signatures. Owners of such keys can resolve this with the cross-certifycommand available in the key editing mode of the latest gpg. You can read the official…

Squid is a very popular forward proxy server that can be configured to work as a reverse proxy. However Varnish was designed from the start as a reverse proxy. Additionally, Varnish has a better configuration system that allows you to rewrite URLs and performs and scales better than Squid because Varnish is a multi-threaded application whereas Squid uses only one process. Lastly in its favour, Varnish has better invalidation support. On the other hand, Squid has built-in SSL support, whereas Varnish needs additional setup to support SSL. Also, Squid has support for antivirus plugins which might be really important for certain types of user. And finally, Squid is more mature than Varnish because it first appeared in July 1996. If the aforementioned differences make no sense to you, it means…

Many people who take on app development already have a background in HTML, CSS and JavaScript that are popular front-end technologies for building websites. There are few steps involved to making this happen – first of all, open your terminal. You need Node.js and Nodejs package manager installed, Apache Cordova, and optionally, Ionic Framework. sudo apt-get update sudo apt-get install nodejs sudo apt-get install npm sudo npm install -g cordova sudo npm install -g ionic Now that the required packages are installed, let’s move on to setup and editing. First, let’s start a new Apache Cordova project. The first step is to navigate to the folder where you will store the package. For an easy demo, you can simply use the desktop: cd Desktop mkdir cordova cd cordova At this…

Puppy Linux is a longstanding ultra-lightweight distro. Dog Linux is an example of what happens when a Puppy grows up, becoming stronger, but still lightweight. There are two Dog Linux variants. One is based on Debian, but this is the one based on Ubuntu, Xenial Xerus. XenialDog has a persistent save option – if you have a partition with a label of casper-rw, or a file called casper-rw in the root of a hard disk partition, any changes will be saved there. Login details: username & password puppy…

The stupid thing is that we all know to keep our desktop and server up to date, right? We truly hope so. The simple reason being that new exploits are being discovered all the time – let’s not even get into the CIA Vault 7 revelations see page 7 – so unless you can keep your infrastructure updated, you have no security. If you have no control over a device’s updates, how can you know it’s secure? Well, you can’t. That’s why we push so much for people to develop, build and maintain their own IoT devices. Sure, devices hidden behind your own broadband NAT are largely secure, but if they need to communicate to the big beyond that’s a different story. With the release of the all-new Raspberry Pi…

SHA-1, also known as Secure Hash Algorithm 1, is a popular cryptographic hashing function created in 1995 by the NSA. However its future is now in doubt after Google and the CWI Institute Amsterdam announced they had launched the first ever successful SHA-1 collision attack. SHA-1 was designed to turn any input message (such as a specific file or website certificate) into a long string of numbers and letters that can be used as a fingerprint to confirm that the file is genuine. In their release (see http://bit.ly/2moNUQB), Google and the CWI Institute revealed that they managed to create two PDFs that had identical SHA-1 hashes, but contained different content. Malicious users could use a ‘collision’ like this to deceive systems that use the hashes into accepting a malicious file.…

FREENAS CORRAL FreeNAS 10 has left its development phase and is now known as FreeNAS Corral. The new name is down to the major changes the project has included in this release, leaving its creators to feel that simply numbering it “10” would be a disservice. Among other improvements, FreeNAS gets a brand new look with a user-friendly web-based interface, ZFS support and now allows administrators to run containerised applications. For more information on the new release and to download the latest version, visit: http://bit.ly/2ndI6g3. CHAKRA GNU/LINUX 2017.03 The semi-rolling distribution Chakra GNU/Linux has just received a major update, codenamed Goedel in honour of the mathematician and philosopher Kurt Goedel (which the rest of the world spells “Gödel”). According to the release notes provided with it, there are two major…

Closed Amiga In response to your reply to Ian Learmonth in Linux Format 218 December 2016, “AmigaDOS... was and remains closed source, while as we all know far better options now exist for everyone.” Commodore and Amiga hardware, in terms of Amiga branded PCs running proprietary designs, was certainly closed source. So was everybody, before largely IBM PC manufacturers began collaborating on common standards for computers. And so was the firmware and software supplied by Commodore and later Gateway (briefly). Such items were rare then, and are rarer now, and to a certain extent there is a kind of nascent support, in that various gadgets and gizmos still get released for that hardware, like memory card interfaces and other bits. However, to a certain extent, all of those early systems…

The Ryzen release gave tech pundits a lot to, er, process, in terms of decoding the marketing speak, running independent benchmarks to compare with those promulgated by AMD and, most importantly, deciding whether they should invest in the new chippery. But for open source denizens there was another surprise: AMD representatives on Reddit acknowledged the possibility that they might eventually release the necessary bits that would enable free firmware, such as Libreboot, to run on Ryzen-powered machines. The Free Software Foundation is especially concerned by AMD’s Platform Security Processor (PSP), as well as the rival Intel Management Engine. This code runs on independent ARM processors that initialise the x86 cores and potentially has transparent access to anything that system is doing henceforth. But there are other components and keys that…

Sharing ideas is part of the backbone of Linux, along with the principle of free and open source software, and this will be the same in your adventures in using CAD software. To be able to share designs, you either need to use the same software or the same file format. Existing services on the web use different formats depending on their focus. 3D-focused sites use STL format, spare parts from suppliers use DXF or DWG files but often STL files too. LibreCADuses DXF files, which are great for 2D CAD drawings, which in this case is the purpose of the software. Many of the suppliers, however, deliver both 2D and 3D DXF and DWG drawings for you to incorporate in your projects, so it is a little limiting that…

Don’t rule out using web-based solutions: they keep updated and add new features continually. There are plenty available, free ones usually ask for payment only if you need to have private drawings. Tinkercadis a playful 3D modeller made by the original giant of CAD, Autodesk. They also have professional services which we have not covered here. Onshapeis a great cloud-based application where you can create fully functional and truly professional drawings, for free, with the caveat that all your drawings will be public. The tutorials provided are awesome and come as a document that you can copy. Onshapeis particularly geared towards working on online collaborative projects. There is also the openjscad.org site where you can edit and view the results of the JSCAD language for building 3D shapes. The language…

The Pi Zero was a surprise in late 2015. It introduced a new type of Raspberry Pi, one that eschewed high specifications for a cheaper, smaller board. The original Zero was just missing one thing, but then so was the then flagship Raspberry Pi 2. What it lacked was wireless connectivity. With the release of the Pi 3 in early 2016 we saw Wifi and Bluetooth added to the Pi, and now these features have trickled down to the Pi Zero W. The Pi Zero W is almost identical to the previous models of Zero. It comes with the same camera (CSI) port that was introduced with V1.3 of the Zero and the same unsoldered 40 pin GPIO (General Purpose Input Output) interface to connect your Pi to electronic devices…

Linux Format: Hi Eben, thanks for taking the time to speak to LXF. So the Raspberry Pi Zero W has just been released, but why do we need another Raspberry Pi? Eben Upton: We saw that a lot of people were plugging WiFi and Bluetooth dongles into their original Pi Zero. When we first released the Pi Zero in 2015 we didn’t have any of our own wireless products in the market as we were still shipping Raspberry Pi 2 and working on the yet to be released Raspberry Pi 3. The lessons that we learnt by creating the wireless package for the Raspberry Pi 3 were rolled up and added to the new Pi Zero W. This was for two reasons, firstly and obviously you don’t need to plug…

ON ‘SOMETHING NEW’“We’re a party that doesn’t want to exist. We shouldn’t need to be there.” James Smith is Head of Labs at the Open Data Institute. Like many in the UK, James (@floppy on Twitter) was frustrated at the state of UK politics. Unlike many though, he took his software wrangling skills and used them to make a stand, starting his own political party, Something New. He stood for election in 2010, and while this was unsuccessful he has continued to develop the idea of an open source party manifesto, central to the syncretic vision of Something New. We met him after his talk at OSCON Europe to discuss his experience. You can read his call to action “It’s Time to Step Up” at https://floppy.org.uk/blog/2013/07/05/  its-time-to-step-up. Linux…

Private copying of copyrighted material is illegal in the UK, but the concern of this article is with rightful access to legally purchased Blu-rays. Unfortunately on Linux this requires digital circumvention – something that has been hotly debated for years and continually head-butts against Fair Use Rights. In the United States, the Digital Millennium Copyright Act (DMCA) criminalises decrypting protected content (even if legally purchased), and US courts are still fighting over DMCA versus Fair Use, so you can take it the practice in the USA remains illegal. UK law has been quite draconian in theory, but liberal in practice and has been under constant discussion for years, as the interests of copyright holders continue to run counter to practical realities. Personal copies are legal if you live in The…

Around five years ago, a mysterious organisation named Cicada 3301 began posting a series of increasingly difficult puzzles online in a bid to recruit “highly intelligent individuals”. The first puzzle in 2012 was an image with a small text file at the end. This was encoded with a simple Caesar cipher whereby each letter of the alphabet is shifted a certain number of letters (in this case four). This in turn led to an image of a wooden duck with the message “Woops! Just decoys this way. Looks like you can’t guess how to get the message out.” Savvy crypto-nerds across the world combined their collective genius and realised that the words “guess” and “out” meant that there was a message hidden in the image using Outguess. The solution to…

Our expert Stuart Burns is an expert in large scale virtualisation infrastructure by day. By night, he moonlights as a knowledgeable Linux admin who enjoys tinkering with projects. Many readers will be familiar with using desktop virtualisation products such as VirtualBox or VMware Workstation. These types of virtualisation products are known as ‘type two hypervisors’, which essentially run on top of the operating system alongside normal applications. As solutions they are useful, but they do have limitations. They are not designed to run applications 24/7. Not least because if you have to reboot the underlying PC (or worse, it crashes) all the virtual machines will also have to be rebooted. Type one hypervisors, on the other hand, are designed to run on dedicated hardware that’s as near to bare metal…

Our expert Nate Drake is a freelance technology journalist who specialises in cybersecurity and retro tech. For non-crypto nerds, VeraCryptis a program that enables you to create encrypted containers of any size, inside which you can place your personal photos, bank details or any other data for which the world isn’t ready. VeraCryptmounts these containers with a password, which means only you can access your files. For the uber-paranoid there are even options to combine multiple encryption ciphers and use key files in addition to a password. VeraCryptdoes require you to have some idea in advance of the size of all the files you need. Once an encrypted container has been created, it’s not possible to resize it. What’s more, if you create a container in the full belief that…

Our expert Jonni Bidwell is pleased to have survived the winter. The days are longer, birdsong fills the sky in the evenings and the sound of psytrance is never far away. Wait, that last one was true in the wintertime too. If you followed our previous tutorial, you’ll have seen how it’s possible to access files on the server over the SSH service, using the sftp:// syntax in a file manager. There are also command line tools to do this, namely sftpand scp, but we live in a world of multiple operating systems and not all of these will readily dance to SSH’s tune. Also, sending huge amounts of data over SSH is pretty inefficient – it was never meant for such antics. While Linux has its own filesharing mechanism,…

Our expert John Lane would use GnuPG if he knew anyone else that did. Meanwhile, he’ll just polish his key. GnuPG, the “Gnu Privacy Guard”, is a privacy tool you can use to encrypt email or verify the authenticity of software packages before installing them. It’s an implementation of the OpenPGP standard that relies on public-key cryptography keys that have provable authenticity through certification and trust. The GnuPG documentation explains early-on that good key management is essential. So, in this tutorial, we will focus on key management and explore best-practice with that aim in mind. We’re using GnuPG version 2.1, nicknamed “Modern”. Some basics A GnuPG key has public and private components referred to individually as a public key and private key, and together as a key-pair. Private keys are…

Our expert Mihalis Tsoukalos is a Unix administrator, a programmer, a DBA and a mathematician who enjoys writing articles and learning new things. Varnish is a caching HTTP reverse proxy that acts as a transparent layer between your web server and its web clients. It operates by caching content in order to deliver it faster without the web client having to wait for the web server. In other words, Varnish cannot operate on its own, as it needs to be in front of a properly configured web server. The most significant advantage of Varnish is that it makes the response time of your sites faster. This tutorial will showcase the basic Varnish functionality; however, Varnish can do many more things than those presented here. And although it can work with…

Our expert Kent Elchuk is an experienced web developer who has built, secured and maintained many web applications for high schools, colleges and web sites. You may have an Android device and have downloaded apps for it from Google Play. You may, at some point, have wondered what they are and how they got there. You may even have gone to the next level and asked yourself, “How do I build my own app?” This article will dispense with the mystery and guide you through the basics and the essentials of building your own Android App. You will learn how to download and install Android Studio (which is free), build an app, test that app on emulators and a real Android device such as a Samsung Note phone, and then…

If you have issues, they can normally be cleared up with some simple edits to the .bashrc file, or Java may need a bit of a makeover. For starters, if the ANDROID_HOME path is off you can find it in Android Studio by loading a working app then locating the path by clicking Tool > Android > SDK Manager. At the top, you will see the path and that will become ANDROID_HOME. With Java, you could install the Java JDK from Oracle after downloading using simple directions from www.java.com/en/download/help/ linux_x64_install.xml. In this case, the folder /usr/java was created and the downloaded tar file was moved to that folder. After extraction, the new folder jdk1.8.0_121 is created. This becomes JAVA_HOME. You will likely want to uninstall and remove old versions which could…

Microsoft has announced at the 2017 Open Compute Project US summit that its Project Olympus, a “next generation cloud hardware design and a new model for open source hardware development” has become the first OCP server design to offer a range of microprocessors that are fully compliant with the Universal Motherboard specification. Both Intel and AMD have collaborated on Project Olympus with their latest server processors, along with Qualcomm, Cavium and other companies to shape ARM64 cloud servers. Nvidia is also lending its graphics might, helping Microsoft define a blueprint which the Redmond company hopes will define a new era of open source hardware development. You can read more about Project Olympus at: http://bit.ly/2ndiQ9V. Mozilla, the company behind Firefox and Thunderbird, has announced its first strategic acquisition: Pocket. It’s an…

“While Mesa 17.0 was undoubtedly the biggest news on the open source graphics front over the past few months, the release of Weston 2.0, the reference compositor for Wayland, also brought its fair share of improvements. In addition to numerous bugfixes, atomic mode setting support is now in the pipeline, promising to deliver on the basic premise that clients will be able to have their content displayed directly on hardware overlay planes, with no specific hardware knowledge required to achieve this. Another big change is the jump to version 2.0, the result of developments in libweston, the API enabling external window managers and desktop environments to reuse Weston’s solid and complete core code. Tying Weston to one particular window manager or desktop environment would have limited both scope and reach,…

The Tuxguitar review in LXF219 shows what a wide range of applications are available across all the platforms these days. Tuxguitar is great for music composition, as you have highlighted, but the review misses one of Tuxguitar’s major strengths – it’s a great teaching tool. It allows you to select which of the instrument tracks to follow and, more importantly, it allows you to slow down the tempo so that while you are learning you can keep pace with the playback. Other features worth a mention are the ability to put guitar chord diagrams at appropriate places alongside of the music, and the fact that it can import files created by other programs such as Guitar Pro and the standard Midi files. A simple search on the web and you…

Ryzen 5 Although AMD’s Ryzen 7 series forms the vanguard of its new assault on Intel’s overpriced CPU monopoly, it’s the 5 series that will really throw a spanner into its rival’s works. It promises multithreaded processors featuring both six and four core variants, which means we could be looking at a 12-threaded low-power chips coming in at around £200, and a four-core eight-thread chip at £140 or less. Ryzen 3 With Ryzen 3, we will likely see lower clocked, four-core chips straddling this range too. Although details are currently scarce, rumour has it that these chips will be the APUs of AMD’s new arsenal, delivering HBM and Radeon RX 460 level of performance on processors costing less than £100 a pop, a heady combination. Naples And then there’s Naples.…

Even if you have experience with CAD software, it is essential to practise methodically, exploring the different methods and tools available. We will now look at how much training is needed to get the hang of each program in our roundup. The quality of a program’s documentation is also important but it is not a practical way to get started: tutorials are much faster. LibreCADhas moderate but clear documentation, the tutorials are usually clear and useful. Many are in French, German and Spanish but all the basics are covered by English speakers. FreeCADhas a brilliant solution where you can view their web based documentation in a FreeCADtab, eliminating the need to swap to your browser for help. The tutorials on YouTube cover everything from the basics to making meshes for…

Since the Raspberry Pi was released, the official operating system has been Raspbian, and in late 2016 we saw the release of the latest version, named Pixel. It brought an improvement in the general speed and interface, as well as updated and new software. To develop using Python you can use either Python 2 or 3 via the IDLE Python editor, or for those who prefer a more flexible editor you can now use Geany, a common editor in the Linux community with a series of plugins that can turn it into a programming powerhouse for many different languages, not just Python. Nor is the Pi just for programming. It can be a low-power server for your files, or a web server. The power of Linux is that it can…

Trying to stream Blu-rays with MakeMKV can be confusing at first, as the given address won’t work in your media player. Worry not, it’s as easy as one, two, three… 1) Copy the address in MakeMKV’s output text (http://localhost: 51000) and paste that into your web browser. 2) Here you’ll be provided with an HTML interface to browse the disc’s structure: chances are the film will be on “title1”, and the file duration should provide a clue as to which file is which. 3) Copy the address of the title you want and nowyou can play it in just about any player you like.…

Mobile World Congress 2017, which this year ran from 27 February to 2 March, is the premier conference for the mobile industry. It showcases the latest mobile developments from telecommunications operators, IoT makers and innovators, and leaders in enterprise. Mike Bell manned Canonical’s stand there and was kind enough to chat with us and share his experiences. An industry veteran, he’s been CTO for Jaguar Land Rover, then director for their Global Connected Car program. Going back further, he’s been in charge of Information Systems Strategy & Architecture at United Utilities. Building on these experiences he now heads Canonical’s Devices and IoT team, and we were excited to hear what they’ve been up to. Linux Format: Our budget didn’t extend to sending me to Barcelona, so how was MWC 2017?…

1 Install Outguess Boot up your operating system of choice (ideally TAILS in this instance) and open the Terminal. Run sudo apt-get update then run sudo apt-get install outguess. While the update and install is running, take the time to move your outer container file as well as the real and fake files into your home folder. Feel free to name these files something as obvious as “real” and “fake”, as Outguess doesn’t store the original filenames. 2 Encode files Assume the container file is called cabinet. jpg and the real and fake files are called real. jpg and fake.jpg, encoded with the passwords “narly” and “bogus” respectively. The output file is called cabinet1.jpg. In this case the command to hide the files would be: outguess -k “bogus” -d fake.png…

Alongside conventional virtual machines such as the ones we have created in this tutorial, ProxMox also supports the use of containers. Linux Containers (LXCs) provide a way of running several servers or services in isolation but using the same virtual host, thereby saving a lot of memory and other system overhead that would be consumed when using classic virtualisation. Linux Containers provide a semi isolated environment in which servers can be run. Containers are not suitable for everything but they can be ideal for running services. Containers are also useful because they are exceptionally portable and moving them between servers is a quite straightforward process. Linux Containers also remove a lot of the configuration issues that are encountered when deploying classic VMs. These services run on top of the server.…

As convenient as TruPaxis for creating volumes of just the right size, this comes at the price of extra security. If you wish you can also add a key file. This means in order to mount your TruPaxvolume, VeraCryptwould use both your password and a file. This is a form of Two Factor Authentication (something you have and something you know) and hugely reduces the chance that an attacker can access your volume. VeraCryptalso has a random keyfile generator. Go to Tools > Keyfiles to launch this. You can use one or a number of files. Remember that the first 64 kilobytes of the file must not change, or the container can’t be opened. This is why images and music files work better. VeraCryptdoesn’t alter the file, so if for…

With an updated package database we can install Samba and its dependencies with a simple command line call: $ sudo apt-get install samba If you are prompted to insert the install CD at this point, as we were, then you have two choices. Either do as it says, or comment out the line beginning deb cdrom in /etc/apt/sources. list. Debian seems overly keen to save bandwidth here, but since packages on the installation media are likely to be out of date before long, it’s not really being much help in the wider scheme of things. Webminis a trickier proposition to install – it’s not in the official Debian repositories, but a .deb file is available which will ensure the package’s dependencies are satisfied and that it will be updated with…

GnuPG uses a gpg-agentdaemon to manage keys for gpgand this uses a pinentry helper tool whenever it requires interactive passphrase input. For this to work properly, your shell’s tty device must be owned by you (eg, for Alice, stat -c %U $(tty) must be alice). This won’t be the case if you used sudoor su, and this may cause problems with tasks such as key generation that require access to secret keys; you might see an error like this: gpg: agent_genkey failed: Permission denied If this happens to you, try this little trick that takes advantage of the scriptcommand to do the key generation in a ttythat you own: $ script -q -c gpg ... /dev/null where the command you wish to use, plus all of its arguments are contained…

HTTP caching is a way of storing web traffic so that people connecting to it use the caching server instead of the actual site, thus making everything faster. The reasons that we use HTTP caching are firstly that clients will feel that their internet connection is performing faster, and secondly that you can both filter and transform your traffic. A side effect of HTTP caching is that clients might still be able to get web pages even if the actual web site is down, provided that they are already stored in the cache. A proxy server interacts with the clients and the destination web server in the following fashion. When the proxy server receives a request that can be served either by its memory cache or by its hard disk…

The heart of the tutorial was about building a simple webview app. But what if you want to create buttons that will link to external sources? Some very simple modifications can be made to the main class in your app, located in the Example.java file which was described in the article body. The main code change will take place within the Example class as shown below. public class Example extends Activity { Button button; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_test); addListenerOnButton(); } @Override public boolean onCreateOptionsMenu(Menu menu) { getMenuInflater().inflate(R.menu.test, menu); return true; } public void addListenerOnButton() { button = (Button) findViewById(R.id. mybutton); button.setOnClickListener(new OnClickListener() { @Override public void onClick(View arg0) { Intent browserIntent = new Intent(Intent. ACTION_VIEW, Uri.parse(" https://example.com ")); startActivity(browserIntent); } }); } Now, we will describe…

Our expert Mihalis Tsoukalos (@mactsouk) has an M.Sc. in IT from UCL and a B.Sc. in Mathematics, which makes him a DB-admining, software-coding, Unix-using, mathematical machine. You can reach him at www.mtsoukalos.eu. This tutorial will teach you how to implement the basic functionality of the find command line utility in Python 3. It’s a very popular and handy Unix tool that helps you find files and directories wherever they are on your Linux machine. This tutorial will implement a small part of find. However, once you understand the Python 3 code presented, you can add features on your own. The basics of find This section will illustrate the use of the findutility using easy to understand examples. For instance, this example shows simple uses of find: $ find /home/mtsouk -name…

As this tutorial uses some relatively complex Python methods, it is very important to carefully read the documentation of each method before using it, otherwise you’ve learned little. There are various places where you can look for documentation including the Python 3 documentation site, the pydoc3 command line utility and the Python 3 shell. Most of the time the Python 3 documentation site has the most up to date information. The important thing is trying to understand the presented information and the subtleties of the methods you want to use. There are times where a small option can make the difference between a working and a non-working program. Should you wish to learn more about the os.scandir() method, visit https://docs.python.org/3/library/os.html#os.scandir.…

I suffered a minor, and self-inflicted, disaster recently. I won’t bore you with the details but I managed to do the equivalent of rm -fr /*, even though current versions of rm protect you from such idiocy, and wipe part of my OS before I could stop it! Fortunately, I’m diligent about backups, so I restored my root filesystem from the previous day’s backup and thought all would be well. It wasn’t – I had all sorts of apparently unrelated problems. Installing some software failed with an error message that shouldn’t happen and I couldn’t print or do various other things that my brain has purged from memory in an attempt to preserve my sanity. I tried to work through each problem, looking for causes that I couldn’t always find.…

Linux benchmarking Open source system testing, stress testing and performance gauging, we show you how. Maker Faire 2017 We report live from the faire floor to dish the dirt on the best new projects and all the maker fun. Build a router Why you ask, because we can! Combine Ubuntu server and old hardware for a home routing solution. Contents of future issues subject to change – we might be too busy filling in spreadsheets to plan it……