Episode 242

Linux Takes The Fastpath | BSD Now 242


April 18th, 2018

1 hr 23 mins 20 secs

Your Hosts

About this Episode

TrueOS Stable 18.03 released, a look at F-stack, the secret to an open source business model, intro to jails and jail networking, FreeBSD Foundation March update, and the ipsec Errata.


TrueOS STABLE 18.03 Release

The TrueOS team is pleased to announce the availability of a new STABLE release of the TrueOS project (version 18.03). This is a special release due to the security issues impacting the computing world since the beginning of 2018. In particular, mitigating the “Meltdown” and “Spectre” system exploits make it necessary to update the entire package ecosystem for TrueOS. This release does not replace the scheduled June STABLE update, but provides the necessary and expected security updates for the STABLE release branch of TrueOS, even though this is part-way through our normal release cycle.

  • Important changes between version 17.12 and 18.03

    • “Meltdown” security fixes: This release contains all the fixes to FreeBSD which mitigate the security issues for systems that utilize Intel-based processors when running virtual machines such as FreeBSD jails. Please note that virtual machines or jails must also be updated to a version of FreeBSD or TrueOS which contains these security fixes.
    • “Spectre” security mitigations: This release contains all current mitigations from FreeBSD HEAD for the Spectre memory-isolation attacks (Variant 2). All 3rd-party packages for this release are also compiled with LLVM/Clang 6 (the “retpoline” mitigation strategy). This fixes many memory allocation issues and enforces stricter requirements for code completeness and memory usage within applications. Unfortunately, some 3rd-party applications became unavailable as pre-compiled packages due to non-compliance with these updated standards. These applications are currently being fixed either by the upstream authors or the FreeBSD port maintainers. If there are any concerns about the availability of a critical application for a specific workflow, please search through the changelog of packages between TrueOS 17.12 and 18.03 to verify the status of the application.

Most systems will need microcode updates for additional Spectre mitigations. The microcode updates are not enabled by default. This work is considered experimental because it is in active development by the upstream vendors. If desired, the microcode updates are available with the new devcpu-data package, which is available in the Appcafe. Install this package and enable the new microcode_update service to apply the latest runtime code when booting the system.

  • Important security-based package updates

    • LibreSSL is updated from version 2.6.3 -> 2.6.4
    • Reminder: LibreSSL is used on TrueOS to build any package which does not explicitly require OpenSSL. All applications that utilize the SSL transport layer are now running with the latest security updates.
    • Browser updates: (Keep in mind that many browsers have also implemented their own security mitigations in the aftermath of the Spectre exploit.)
    • Firefox: 57.0.1 -> 58.0.2
    • Chromium: 61.0.3163.100 -> 63.0.3239.132
    • Qt5 Webengine (QupZilla, Falkon, many others): 5.7.1 -> 5.9.4
  • All pre-compiled packages for this release are built with the latest versions of LLVM/Clang, unless the package explicitly requires GCC. These packages also utilize the latest compile-time mitigations for memory-access security concerns.


F-Stack is an user space network development kit with high performance based on DPDK, FreeBSD TCP/IP stack and coroutine API. http://www.f-stack.org

  • Introduction With the rapid development of NIC, the poor performance of data packets processing with Linux kernel has become the bottleneck. However, the rapid development of the Internet needs high performance of network processing, kernel bypass has caught more and more attentions. There are various similar technologies appear, such as DPDK, NETMAP and PF_RING. The main idea of kernel bypass is that Linux is only used to deal with control flow, all data streams are processed in user space. Therefore, kernel bypass can avoid performance bottlenecks caused by kernel packet copying, thread scheduling, system calls and interrupts. Furthermore, kernel bypass can achieve higher performance with multi optimizing methods. Within various techniques, DPDK has been widely used because of its more thorough isolation from kernel scheduling and active community support.

  • F-Stack is an open source network framework with high performance based on DPDK. With following characteristics

    • Ultra high network performance which can achieve network card under full load, 10 million concurrent connections, 5 million RPS, 1 million CPS.
    • Transplant FreeBSD 11.01 user space stack, provides a complete stack function, cut a great amount of irrelevant features. Therefore greatly enhance the performance.
    • Support Nginx, Redis and other mature applications, service can easily use F-Stack
    • With Multi-process architecture, easy to extend
    • Provide micro thread interface. Various applications with stateful app can easily use F-Stack to get high performance without processing complex asynchronous logic.
    • Provide Epoll/Kqueue interface that allow many kinds of applications easily use F-Stack
  • History

In order to deal with the increasingly severe DDoS attacks, authorized DNS server of Tencent Cloud DNSPod switched from Gigabit Ethernet to 10-Gigabit at the end of 2012. We faced several options, one is to continue to use the original model another is to use kernel bypass technology. After several rounds of investigation, we finally chose to develop our next generation of DNS server based on DPDK. The reason is DPDK provides ultra-high performance and can be seamlessly extended to 40G, or even 100G NIC in the future.

After several months of development and testing, DKDNS, high-performance DNS server based on DPDK officially released in October 2013. It's capable of achieving up to 11 million QPS with a single 10GE port and 18.2 million QPS with two 10GE ports. And then we developed a user-space TCP/IP stack called F-Stack that can process 0.6 million RPS with a single 10GE port.

With the fast growth of Tencent Cloud, more and more services need higher network access performance. Meanwhile, F-Stack was continuous improving driven by the business growth, and ultimately developed into a general network access framework. But this TCP/IP stack couldn't meet the needs of these services while continue to develop and maintain a complete network stack will cost high, we've tried several plans and finally determined to port FreeBSD(11.0 stable) TCP/IP stack into F-Stack. Thus, we can reduce the cost of maintenance and follow up the improvement from community quickly.Thanks to libplebnet and libuinet, this work becomes a lot easier.

With the rapid development of all kinds of application, in order to help different APPs quick and easily use F-Stack, F-Stack has integrated Nginx, Redis and other commonly used APPs, and a micro thread framework, and provides a standard Epoll/Kqueue interface.

Currently, besides authorized DNS server of DNSPod, there are various products in Tencent Cloud has used the F-Stack, such as HttpDNS (D+), COS access module, CDN access module, etc..


Leadership Is The Secret To An Open Source Business Model

  • A Forbes article by Mike Lauth, CEO of iXsystems
    There is a good chance you’ve never heard of open source software and an even greater one that you’re using it every day without even realizing it. Open source software is computer software that is available under a variety of licenses that all encourage the sharing of the software and its underlying source code. Open source has powered the internet from day one and today powers the cloud and just about everything connected to it from your mobile phone to virtually every internet of things device. FreeNAS is one of two open source operating systems that my company, iXsystems, develops and distributes free of charge and is at the heart of our line of TrueNAS enterprise storage products. While some of our competitors sell storage software similar to FreeNAS, we not only give it away but also do so with truly no strings attached -- competitors can and do take FreeNAS and build products based on it with zero obligation to share their changes. The freedom to do so is the fundamental tenet of permissively licensed open source software, and while it sounds self-defeating to be this generous, we’ve proven that leadership, not licensing, is the true secret to a successful open source business model. We each have our own personal definition of what is fair when it comes to open source. At iXsystems, we made a conscious decision to base FreeNAS and TrueOS on the FreeBSD operating system developed by the FreeBSD project. We stand on the shoulders of giants by using FreeBSD and we consider it quite reasonable to give back on the same generous terms that the FreeBSD project offers us. We could be selective in what we provide free of charge, but we believe that doing so would be short-sighted. In the long game we’re playing, the leadership we provide over the open source projects we produce is infinitely more important than any restrictions provided by the licenses of those and other open source projects. Twenty years in, we have no reason to change our free-software-on-great-hardware business model and giving away the software has brought an unexpected side-benefit: the largest Q/A department in the world, staffed by our passionate users who volunteer to let us know every thought they have about our software. We wouldn’t change a thing, and I encourage you to find exactly what win-win goodwill you and your company can provide to your constituents to make them not just a customer base but a community.
  • Drive The Conversation It took a leap of faith for us to give away the heart of our products in exchange for a passionate community, but doing so changes your customer's relationship with your brand from priced to priceless. This kind of relationship leverages a social contract instead of a legal one. Taking this approach empowers your users in ways they will not experience with other companies and it is your responsibility to lead, rather than control them with a project like FreeNAS
  • Relieve Customer Pain Points With Every New Release Responsiveness to the needs of your constituents is what distinguishes project leadership from project dictatorship. Be sure to balance your vision for your products and projects with the “real world” needs of your users. While our competition can use the software we develop, they will at best wow users with specific features rather than project-wide ones. Never underestimate how grateful a user will be when you make their job easier.
  • Accept That A Patent Is Not A Business Model Patents are considered the ultimate control mechanism in the technology industry, but they only provide a business model if you have a monopoly and monopolies are illegal. Resist getting hung up on the control you can establish over your customers and spend your time acquiring and empowering them. The moment you both realize that your success is mutual, you have a relationship that will last longer than any single sale. You’ll be pleasantly surprised how the relationships you build will transcend the specific companies that friends you make work for.
  • Distinguish Leadership From Management Every company has various levels of management, but leadership is the magic that creates markets where they did not exist and aligns paying customers with value that you can deliver in a profitable manner. Leadership and vision are ultimately the most proprietary aspects of a technology business, over every patentable piece of hardware or licensable piece of software. Whether you create a new market or bring efficiency to an existing one, your leadership is your secret weapon -- not your level of control.

News Roundup

Introduction to Jails and Jail Networking on FreeBSD

Jails basically partition a FreeBSD system into various isolated sub-systems called jails. The syscall and userspace tools first appeared in FreeBSD 4.0 (~ March 2000) with subsequent releases expanding functionality and improving existing features as well as usability. + For Linux users, jails are similar to LXC, used for resource/process isolation. Unlike LXC however, jails are a first-class concept and are well integrated into the base system. Essentially however, both offer a chroot-with-extra-separation feeling. Setting up a jail is a fairly simple process, which can essentially be split into three steps: + Place the stuff you want to run and the stuff it needs to run somewhere on your filesystem. + Add some basic configuration for the jail in jail.conf. + Fire up the jail. To confirm that the jail started successfully we can use the jls utility: We can now enter the jailed environment by using jexec, which will by default execute a root shell inside the named jail A jail can only see and use addresses that have been passed down to it by the parent system. This creates a slight problem with the loopback address: The host would probably like to keep that address to itself and not share it with any jail. Because of this, the loopback-address inside a jail is emulated by the system: + is an alias for the first IPv4-address assigned to the jail. + ::1 is an alias for the first IPv6-address assigned to the jail. While this looks simple enough and usually works just fine[tm], it is also a source of many problems. Just imagine if your jail has only one single global IPv4 assigned to it. A daemon binding its (possibly unsecured) control port to the loopback-address would then unwillingly be exposed to the rest of the internet, which is hardly ever a good idea. + So, create an extra loopback adapter, and make the first IP in each jail a private loopback address + The tutorial goes on to cover making multiple jails share a single public IP address using NAT + It also covers more advanced concepts like ‘thin’ jails, to save some disk space if you are going to create a large number of jails, and how to upgrade them after the fact + Finally, it covers the integration with a lot of common tools, like identifying and filter jailed processes using top and ps, or using the package managers support for jails to install packages in a jail from the outside.


SmartOS release-20180315

``` Hello All, The latest bi-weekly "release" branch build of SmartOS is up:
curl -C - -O https://us-east.manta.joyent.com/Joyent_Dev/public/SmartOS/smartos-latest.iso
curl -C - -O https://us-east.manta.joyent.com/Joyent_Dev/public/SmartOS/smartos-latest-USB.img.bz2
curl -C - -O https://us-east.manta.joyent.com/Joyent_Dev/public/SmartOS/smartos-latest.vmwarevm.tar.bz2
A generated changelog is here:
The full build bits directory, for those interested, is here in Manta:


Firewall rules created with fwadm(1M) can now use the PRIORITY keyword to specify a higher precedence for a rule. This release has includes mitigation of the Intel Meltdown vulnerability in the form of kpti (kernel page table isolation) with PCID (process context identifier) support This release also includes experimental support for bhyve branded zones.

General Info

Every second Thursday we roll a "release-YYYYMMDD" release branch and builds for SmartOS (and Triton DataCenter and Manta, as well). Cheers, Josh Wilsdon, on behalf of the SmartOS developers https://smartos.org ```
  • Here's a screencap from q5sys' machine showing the output of sysinfo: https://i.imgur.com/MFkNi76.jpg

FreeBSD Foundation March 2018 Update

  • > Syzkaller update: Syzkaller is a coverage-guided system call fuzzer. It invokes syscalls with arbitrary and changing inputs, and is intended to use code coverage data to guide changes to system call inputs in order to access larger and larger portions of the kernel in the search for bugs.
  • > Last term’s student focused largely on scripts to deploy and configure Syzkaller on Packet.net’s hosting infrastructure, but did not get to the code coverage integration required for Syzkaller to be effective. This term co-op student Mitchell Horne has been adding code coverage support in FreeBSD for Syzkaller.
  • > The Linux code coverage support for Syzkaller is known as kcov and was submitted by Dmitry Vyukov, Syzkaller’s author. Kcov is purposebuilt for Syzkaller:
    • > kcov provides code coverage collection for coverage-guided fuzzing (randomized testing). Coverage-guided fuzzing is a testing technique that uses coverage feedback to determine new interesting inputs to a system.
    • > kcov does not aim to collect as much coverage as possible. It aims to collect more or less stable coverage that is function of syscall inputs. To achieve this goal it does not collect coverage in soft/hard interrupts and instrumentation of some inherently non-deterministic or non-interesting parts of kernel is disabled (e.g. scheduler, locking).
  • > Mitchell implemented equivalent functionality for FreeBSD - a distinct implementation, but modelled on the one in Linux. These patches are currently in review, as are minor changes to Syzkaller to use the new interface on FreeBSD.
  • > We still have some additional work to fully integrate Syzkaller and run it on a consistent basis, but the brief testing that has been completed suggests this work will provide a very valuable improvement in test coverage and opportunities for system hardening: we tested Syzkaller with Mitchell's code coverage patch over a weekend. It provoked kernel crashes hundreds of times faster than without his work.
  • > I want to say thank you to NetApp for becoming an Iridium Partner again this year! (Donations between $100,000 - $249,999) It’s companies like NetApp, who recognize the importance of supporting our efforts, that allow us to continue to provide software improvements, advocate for FreeBSD, and help lead the release engineering and security efforts.
  • > Conference Recap: FOSSASIA 2018
  • Foundation Director Philip Paeps went to FOSSASIA, which is possibly the largest open source event in Asia. The FreeBSD Foundation sponsored the conference.
  • Our booth had a constant stream of traffic over the weekend and we handed out hundreds of FreeBSD stickers, pens and flyers. Many attendees of FOSSASIA had never heard of FreeBSD before and are now keen to start exploring and perhaps even contributing. By the end of the conference, there were FreeBSD stickers everywhere!
  • > One particular hallway-track conversation led to an invitation to present FreeBSD at a "Women Who Code" evening in Kuala Lumpur later this week (Thursday 29th March). I spent the days after the conference meeting companies who use (or want to use) FreeBSD in Singapore.
  • > SCaLE 16x: The Foundation sponsored a FreeBSD table in the expo hall that was staffed by Dru Lavigne, Warren Block, and Deb Goodkin. Our purpose was to promote FreeBSD, and attract more users and contributors to the Project. We had a steady flow of people stopping by our table, asking inquisitive questions, and picking up some cool swag and FreeBSD handouts.
  • Deb Goodkin took some tutorials/trainings there and talked to a lot of other open source projects.
  • Next year, we have the opportunity to have a BSD track, similar to the BSD Devroom at FOSDEM. We are looking for some volunteers in Southern California who can help organize this one or two-day event and help us educate more people about the BSDs. Let us know if you would like to help with this effort.

  • Roll Call: #WhoUsesFreeBSD

  • Many of you probably saw our post on social media asking Who Uses FreeBSD. Please help us answer this question to assist us in determining FreeBSD market share data, promote how companies are successfully using FreeBSD to encourage more companies to embrace FreeBSD, and to update the list of users on our website. Knowing who uses FreeBSD helps our contributors know where to look for jobs; knowing what universities teach with FreeBSD, helps companies know where to recruit, and knowing what products use FreeBSD helps us determine what features and technologies to support.

  • New Hosting Partner: Oregon State University Open Source Lab

  • > We are pleased to announce that the Oregon State University (OSU) Open Source Lab (OSL), which hosts infrastructure for over 160 different open source projects, has agreed to host some of our servers for FreeBSD development. The first server, which should be arriving shortly, is an HP Enterprise Proliant DL360 Gen10 configured with NVDIMM memory which will be initially used for further development and testing of permanent memory support in the kernel.
  • Stay tuned for more news from the FreeBSD Foundation in May (next newsletter).

Beastie Bits



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