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Servers: Concurrency, Purism, InSpec, Kubernetes, Docker/Containers

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  • Thinking Concurrently: How Modern Network Applications Handle Multiple Connections

    The idea behind a process is fairly simple. A running program consists of not only executing code, but also data and some context. Because the code, data and context all exist in memory, the operating system can switch from one process to another very quickly. This combination of code + data + context is known as a "process", and it's the basis for how Linux systems work.

    When you start your Linux box, it has a single process. That process then "forks" itself, such that two identical processes are running. The second ("child") process reads new code, data and context ("exec"), and thus starts running a new process. This continues throughout the time that a system is running. When you execute a new program on the command line with & at the end of the line, you're forking the shell process and then exec'ing your desired program in its place.

  • New Purist Services – Standard Web Services Done Ethically

    When you sign up for a communication service, you are typically volunteering to store your personal, unencrypted data on someone else’s remote server farm. You have no way of ensuring that your data is safe or how it is being used by the owner of the server. However, online services are incredibly convenient especially when you have multiple devices.

  • Automated compliance testing with InSpec

    Don't equate compliance through certification with security, because compliance and security are not the same. We look at automated compliance testing with InSpec for the secure operation of enterprise IT.

  • How the Kubernetes Certification Ensures Interoperability

    Dan Kohn, executive director of the Cloud Native Computing Foundation, has called the launch of the new Kubernetes service provider certification program the most significant announcement yet made by the Foundation around the open source container orchestration engine.

    On this new episode of The New Stack Makers from KubeCon + CloudNativeCon 2017, we’ll learn more from Kohn and William Denniss, a product manager at Google, about how the program can help ensure interoperability and why that’s so important.

  • Container Structure Tests: Unit Tests for Docker Images

    Usage of containers in software applications is on the rise, and with their increasing usage in production comes a need for robust testing and validation. Containers provide great testing environments, but actually validating the structure of the containers themselves can be tricky. The Docker toolchain provides us with easy ways to interact with the container images themselves, but no real way of verifying their contents. What if we want to ensure a set of commands runs successfully inside of our container, or check that certain files are in the correct place with the correct contents, before shipping?

  • Prometheus vs. Heapster vs. Kubernetes Metrics APIs

    In this blog post, I will try to explain the relation between Prometheus, Heapster, as well as the Kubernetes metrics APIs and conclude with the recommended way how to autoscale workloads on Kubernetes.

  • Google Introduces Open Source Framework For Testing Docker Images

    Google has announced a new framework designed to help developers conduct unit tests on Docker container images. 

    The Container Structure Test gives enterprises a way to verify the structure and contents of individual containers to ensure that everything is as it should be before shipping to production, the company said in the company’s Open Source blog Jan. 9. 

    Google has been using the framework to test containers internally for more than a year and has released it publicly because it offers an easier way to validate the structure of Docker containers than other approaches, the company said.

More in Tux Machines

Security: OpenSSL, IoT, and LWN Coverage of 'Intelpocalypse'

  • Another Face to Face: Email Changes and Crypto Policy
    The OpenSSL OMC met last month for a two-day face-to-face meeting in London, and like previous F2F meetings, most of the team was present and we addressed a great many issues. This blog posts talks about some of them, and most of the others will get their own blog posts, or notices, later. Red Hat graciously hosted us for the two days, and both Red Hat and Cryptsoft covered the costs of their employees who attended. One of the overall threads of the meeting was about increasing the transparency of the project. By default, everything should be done in public. We decided to try some major changes to email and such.
  • Some Basic Rules for Securing Your IoT Stuff

    Throughout 2016 and 2017, attacks from massive botnets made up entirely of hacked [sic] IoT devices had many experts warning of a dire outlook for Internet security. But the future of IoT doesn’t have to be so bleak. Here’s a primer on minimizing the chances that your IoT things become a security liability for you or for the Internet at large.

  • A look at the handling of Meltdown and Spectre
    The Meltdown/Spectre debacle has, deservedly, reached the mainstream press and, likely, most of the public that has even a remote interest in computers and security. It only took a day or so from the accelerated disclosure date of January 3—it was originally scheduled for January 9—before the bugs were making big headlines. But Spectre has been known for at least six months and Meltdown for nearly as long—at least to some in the industry. Others that were affected were completely blindsided by the announcements and have joined the scramble to mitigate these hardware bugs before they bite users. Whatever else can be said about Meltdown and Spectre, the handling (or, in truth, mishandling) of this whole incident has been a horrific failure. For those just tuning in, Meltdown and Spectre are two types of hardware bugs that affect most modern CPUs. They allow attackers to cause the CPU to do speculative execution of code, while timing memory accesses to deduce what has or has not been cached, to disclose the contents of memory. These disclosures can span various security boundaries such as between user space and the kernel or between guest operating systems running in virtual machines. For more information, see the LWN article on the flaws and the blog post by Raspberry Pi founder Eben Upton that well describes modern CPU architectures and speculative execution to explain why the Raspberry Pi is not affected.
  • Addressing Meltdown and Spectre in the kernel
    When the Meltdown and Spectre vulnerabilities were disclosed on January 3, attention quickly turned to mitigations. There was already a clear defense against Meltdown in the form of kernel page-table isolation (KPTI), but the defenses against the two Spectre variants had not been developed in public and still do not exist in the mainline kernel. Initial versions of proposed defenses have now been disclosed. The resulting picture shows what has been done to fend off Spectre-based attacks in the near future, but the situation remains chaotic, to put it lightly. First, a couple of notes with regard to Meltdown. KPTI has been merged for the 4.15 release, followed by a steady trickle of fixes that is undoubtedly not yet finished. The X86_BUG_CPU_INSECURE processor bit is being renamed to X86_BUG_CPU_MELTDOWN now that the details are public; there will be bug flags for the other two variants added in the near future. 4.9.75 and 4.4.110 have been released with their own KPTI variants. The older kernels do not have mainline KPTI, though; instead, they have a backport of the older KAISER patches that more closely matches what distributors shipped. Those backports have not fully stabilized yet either. KPTI patches for ARM are circulating, but have not yet been merged.
  • Is it time for open processors?
    The disclosure of the Meltdown and Spectre vulnerabilities has brought a new level of attention to the security bugs that can lurk at the hardware level. Massive amounts of work have gone into improving the (still poor) security of our software, but all of that is in vain if the hardware gives away the game. The CPUs that we run in our systems are highly proprietary and have been shown to contain unpleasant surprises (the Intel management engine, for example). It is thus natural to wonder whether it is time to make a move to open-source hardware, much like we have done with our software. Such a move may well be possible, and it would certainly offer some benefits, but it would be no panacea. Given the complexity of modern CPUs and the fierceness of the market in which they are sold, it might be surprising to think that they could be developed in an open manner. But there are serious initiatives working in this area; the idea of an open CPU design is not pure fantasy. A quick look around turns up several efforts; the following list is necessarily incomplete.
  • Notes from the Intelpocalypse
    Rumors of an undisclosed CPU security issue have been circulating since before LWN first covered the kernel page-table isolation patch set in November 2017. Now, finally, the information is out — and the problem is even worse than had been expected. Read on for a summary of these issues and what has to be done to respond to them in the kernel. All three disclosed vulnerabilities take advantage of the CPU's speculative execution mechanism. In a simple view, a CPU is a deterministic machine executing a set of instructions in sequence in a predictable manner. Real-world CPUs are more complex, and that complexity has opened the door to some unpleasant attacks. A CPU is typically working on the execution of multiple instructions at once, for performance reasons. Executing instructions in parallel allows the processor to keep more of its subunits busy at once, which speeds things up. But parallel execution is also driven by the slowness of access to main memory. A cache miss requiring a fetch from RAM can stall the execution of an instruction for hundreds of processor cycles, with a clear impact on performance. To minimize the amount of time it spends waiting for data, the CPU will, to the extent it can, execute instructions after the stalled one, essentially reordering the code in the program. That reordering is often invisible, but it occasionally leads to the sort of fun that caused Documentation/memory-barriers.txt to be written.

US Sanctions Against Chinese Android Phones, LWN Report on Eelo

  • A new bill would ban the US government from using Huawei and ZTE phones
    US lawmakers have long worried about the security risks posed the alleged ties between Chinese companies Huawei and ZTE and the country’s government. To that end, Texas Representative Mike Conaway introduced a bill last week called Defending U.S. Government Communications Act, which aims to ban US government agencies from using phones and equipment from the companies. Conaway’s bill would prohibit the US government from purchasing and using “telecommunications equipment and/or services,” from Huawei and ZTE. In a statement on his site, he says that technology coming from the country poses a threat to national security, and that use of this equipment “would be inviting Chinese surveillance into all aspects of our lives,” and cites US Intelligence and counterintelligence officials who say that Huawei has shared information with state leaders, and that the its business in the US is growing, representing a further security risk.
  • U.S. lawmakers urge AT&T to cut commercial ties with Huawei - sources
    U.S. lawmakers are urging AT&T Inc, the No. 2 wireless carrier, to cut commercial ties to Chinese phone maker Huawei Technologies Co Ltd and oppose plans by telecom operator China Mobile Ltd to enter the U.S. market because of national security concerns, two congressional aides said. The warning comes after the administration of U.S. President Donald Trump took a harder line on policies initiated by his predecessor Barack Obama on issues ranging from Beijing’s role in restraining North Korea to Chinese efforts to acquire U.S. strategic industries. Earlier this month, AT&T was forced to scrap a plan to offer its customers Huawei [HWT.UL] handsets after some members of Congress lobbied against the idea with federal regulators, sources told Reuters.
  • Eelo seeks to make a privacy-focused phone
    A focus on privacy is a key feature being touted by a number of different projects these days—from KDE to Tails to Nextcloud. One of the biggest privacy leaks for most people is their phone, so it is no surprise that there are projects looking to address that as well. A new entrant in that category is eelo, which is a non-profit project aimed at producing not only a phone, but also a suite of web services. All of that could potentially replace the Google or Apple mothership, which tend to collect as much personal data as possible.

today's howtos

Mozilla: Resource Hogs, Privacy Month, Firefox Census, These Weeks in Firefox

  • Firefox Quantum Eats RAM Like Chrome
    For a long time, Mozilla’s Firefox has been my web browser of choice. I have always preferred it to using Google’s Chrome, because of its simplicity and reasonable system resource (especially RAM) usage. On many Linux distributions such as Ubuntu, Linux Mint and many others, Firefox even comes installed by default. Recently, Mozilla released a new, powerful and faster version of Firefox called Quantum. And according to the developers, it’s new with a “powerful engine that’s built for rapid-fire performance, better, faster page loading that uses less computer memory.”
  • Mozilla Communities Speaker Series #PrivacyMonth
    As a part of the Privacy Month initiative, Mozilla volunteers are hosting a couple of speaker series webinars on Privacy, Security and related topics. The webinars will see renowned speakers talking to us about their work around privacy, how to take control of your digital self, some privacy-security tips and much more.
  • “Ewoks or Porgs?” and Other Important Questions
    You ever go to a party where you decide to ask people REAL questions about themselves, rather than just boring chit chat? Us, too! That’s why we’ve included questions that really hone in on the important stuff in our 2nd Annual Firefox Census.
  • These Weeks in Firefox: Issue 30