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;login OCTOBER 2014 VOL. 39, NO. 5 : Operating Systems & Linux Containers James Bottomley and Pavel Emelyanov & Rump Kernels Antti Kantee and Justin Cormack & Push on Green Dan Klein, Dina Bester, and Mathew Monroe & Parables for Sysadmins Andy Seely Columns Health Checks for LDAP Servers David N. Blank-Edelman Python: Pathname Parsing with Path David Beazley iVoyeur: The Lying Mean Dave Josephsen For Good Measure: Testing Dan Geer /dev/random: The Internet of Insecure Things Robert G. Ferrell Conference Reports ATC ’14: 2014 USENIX Annual Technical Conference HotCloud ’14: 6th USENIX Workshop on Hot Topics in Cloud Computing HotStorage ’14: 6th USENIX Workshop on Hot Topics in Storage and File Systems UPCOMING EVENTS OSDI ’14: 11th USENIX Symposium on Operating Systems SaTCPI ’15: National Science Foundation Secure and Design and Implementation Trustworthy Cyberspace Principal Investigators’ October 6–8, 2014, Broomfield, CO, USA Meeting (2015) www.usenix.org/osdi14 January 5–7, 2015, Arlington, VA Co-located with OSDI ’14 and taking place October 5, 2014 Sponsored by the National Science Foundation Presented by USENIX Diversity ’14: 2014 Workshop on Supporting Diversity in Systems Research www.usenix.org/diversity14 FAST ’15: 13th USENIX Conference on File and Storage Technologies HotDep ’14: 10th Workshop on Hot Topics in System February 16–19, 2015, Santa Clara, CA, USA Dependability www.usenix.org/fast15 www.usenix.org/hotdep14 HotPower ’14: 6th Workshop on Power-Aware NSDI ’15: 12th USENIX Symposium on Networked Computing and Systems Systems Design and Implementation May 4–6, 2015, Oakland, CA www.usenix.org/hotpower14 www.usenix.org/nsdi15 INFLOW ’14: 2nd Workshop on Interactions of NVM/ Flash with Operating Systems and Workloads HotOS XV: 15th Workshop on Hot Topics in Operating www.usenix.org/inflow14 Systems May 18–20, 2015, Kartause Ittingen, Switzerland TRIOS ’14: 2014 Conference on Timely Results in Submissions due: January 9, 2015 Operating Systems www.usenix.org/hotos15 www.usenix.org/trios14 USENIX ATC ’15: USENIX Annual Technical Conference LISA14 July 8–10, 2015, Santa Clara, CA, USA November 9–14, 2014, Seattle, WA, USA www.usenix.org/lisa14 Co-located with ATC ’15 and taking place July 6–7, 2015 Co-located with LISA14 HotCloud ’15: 7th USENIX Workshop on Hot Topics in Cloud Computing URES ’14 West: 2014 USENIX Release Engineering Summit West HotStorage ’15: 7th USENIX Workshop on Hot Topics November 10, 2014 in Storage and File Systems www.usenix.org/ures14west UCMS ’14 West: 2014 USENIX Configuration USENIX Security ’15: 24th USENIX Security Symposium Management Summit West August 12–14, 2015, Washington, D.C., USA November 10, 2014 www.usenix.org/ucms14west LISA15 November 8–13, 2015, Washington, D.C., USA SESA ’14: 2014 USENIX Summit for Educators in System Administration November 11, 2014 USENIX Journal of Education in System Administration (JESA) Published in conjunction with SESA www.usenix.org/jesa Do you know about the USENIX Open Access Policy? USENIX is the rst computing association to o er free and open access to all of our conferences proceed- ings and videos. We stand by our mission to foster excellence and innovation while supporting research with a practical bias. Your membership fees play a major role in making this endeavor successful. Please help us support open access. Renew your USENIX membership and ask your colleagues to join or renew today! www.usenix.org/membership twitter.com/usenix www.usenix.org/youtube www.usenix.org/gplus Stay Connected... www.usenix.org/facebook www.usenix.org/linkedin www.usenix.org/blog OCTOBER 2014 VOL. 39, NO. 5 EDITOR Rik Farrow [email protected] EDITORIAL COPY EDITORS Steve Gilmartin 2 Musings Rik Farrow Amber Ankerholz OPERATING SYSTEMS PRODUCTION MANAGER Michele Nelson 6 Containers James Bottomley and Pavel Emelyanov PRODUCTION 11 Rump Kernels: No OS? No Problem! Antti Kantee and Justin Cormack Arnold Gatilao Jasmine Murcia PROGRAMMING TYPESETTER 18 Sirius: Distributing and Coordinating Application Reference Data Star Type Michael Bevilacqua-Linn, Maulan Byron, Peter Cline, Jon Moore, [email protected] and Steve Muir USENIX ASSOCIATION 2560 Ninth Street, Suite 215 SYSADMIN Berkeley, California 94710 26 Making “Push on Green” a Reality Daniel V. Klein, Dina M. Betser, Phone: (510) 528-8649 and Mathew G. Monroe FAX: (510) 548-5738 34 /var/log/manager: Parables of System Administration Management www.usenix.org Andy Seely ;login: is the official magazine of the USENIX Educating System Administrators Charles Border and Kyrre Begnum Association. ;login: (ISSN 1044-6397) 36 is published bi-monthly by the USENIX Association, 2560 Ninth Street, Suite 215, DIVERSITY Berkeley, CA 94710. 40 CRA-W Grad Cohort: Guiding Female Graduate Students Towards $90 of each member’s annual dues is for a Success Dilma Da Silva subscription to ;login:. Subscriptions for non- members are $90 per year. Periodicals postage COLUMNS paid at Berkeley, CA, and additional offices. 42 Practical Perl Tools: Get Your Health Checked David N. Blank-Edelman POSTMASTER: Send address changes to 47 A Path Less Traveled David Beazley ;login:, USENIX Association, 2560 Ninth Street, Suite 215, Berkeley, CA 94710. 52 iVoyeur: Lies, Damned Lies, and Averages Dave Josephsen ©2014 USENIX Association 56 For Good Measure: Testing Dan Geer USENIX is a registered trademark of the 60 /dev/random: The Internet of Things Robert Ferrell USENIX Association. Many of the designations used by manufacturers and sellers to distinguish their products are claimed BOOKS as trademarks. USENIX acknowledges all 62 Book Reviews Rik Farrow and Mark Lamourine trademarks herein. Where those designations appear in this publication and USENIX is aware NOTES of a trademark claim, the designations have been printed in caps or initial caps. 66 USENIX Association Financial Statements for 2013 CONFERENCE REPORTS 68 ATC ’14: 2014 USENIX Annual Technical Conference 82 HotCloud ’14: 6th USENIX Workshop on Hot Topics in Cloud Computing 91 HotStorage ’14: 6th USENIX Workshop on Hot Topics in Storage and File Systems Musings RIK FARROWEDITORIAL Rik is the editor of ;login:. ’ve often rambled on about the future of operating systems, imagining [email protected] something completely different and new. Of course, there are loads of Ipractical issues with that path, like the inability to run any existing software on the spanking new OS. And it turns out there are still things about existing operating systems that can surprise me. I speculated that a future operating system might not look at all like Linux, today’s favorite OS for servers and for OS research projects too. Linux is large, complex, and difficult when it comes to incorporating large changes into it because of its history and design. While the BSD kernels are more modularly designed, they are less popular, and thus not as interesting, or even as well-known. And both are enormous, with many millions of lines of code. While Minix3 is much smaller and actually takes a new approach, it too suffers from the “not as popular as Linux” issue, like the BSDs. I’ve watched the OS space for a while, curious to see if some of the less popular directions taken will pick up a lot of interest. And that interest generally comes from providing features that users, whether they are running servers in some cluster or researchers looking to add the next neat feature or improvement, just can’t live without. Size Is Not Everything Today’s OSes are huge. When I worked with Morrow Designs in the ’80s, I actually put together a set of two, double-density, floppy disks that contained a bootable kernel and utili- ties you needed to recover an unbootable system. That was a total of less than 800 kilobytes of code for the equivalent of a rescue CD, which should sound ridiculous in this day and age. But is it really? The Internet of Things (IoT) already includes inexpensive devices, and that means slower CPUs, small memories, and sometimes relatively generous amounts of flash. With small memories, these devices won’t be booting a generic kernel but one trimmed down to the bare essentials. In one sense, that’s easy enough: You can build a kernel without support for file systems and devices you will never use in a diskless system on chip (SoC) device. Popular examples of this include the Raspberry Pi and the BeagleBone Black. But even these devices are overkill for many IoT applications. Another popular example is the Arduino family, which does not run *nix but may still include networking. Even simpler (and slower with less memory) are the Peripheral Interface Controllers (PICs), favored not just by hobbyists but also by device designers. These devices have really tiny amounts of RAM (really just RAM as registers), yet are more than adequate for many household and industrial devices. They do not run *nix, or even what could ever be called an operating system. Let’s head to the opposite extreme and consider IBM’s Sequoia (Blue Gene/Q) that was installed at Lawrence Livermore National Labs in 2011. Like others in this series, the Sequoia’s compute nodes (some 98,000 of them) run the Compute Node Kernel (CNK). The CNK operating system is just 5000 lines of C++, just enough to communicate with I/O nodes and launch applications that have been compiled just for the CNK environment. The con- cept behind CNK is simple: the bare minimum of memory and processing required so that 2 OCTOBER 2014 VOL. 39, NO. 5 www.usenix.org EDITORIAL Musings most of the CPU and memory can be devoted to computation. The Lineup And it works, as the Sequoia was the world’s fastest computer We begin this issue with two operating systems-related articles. for a while, as well as using 37% less energy than the computer When I met Kirill Korotaev (Parallels) during Linux FAST (BG/K) it replaced.
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  • Next Generation Web Scanning Presentation

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  • Capabilities

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    CS 261, Fall 2015 Scribe notes September 8: Capabilities Scribe: Riyaz Faizullabhoy 1 Motivation for Capabilities In The Confused Deputy, the compiler had two sets of rights: one from the user to access user files such as source code to compile, and another set granted to the compiler intended to access a special statistics file that would collect information about language feature usage. The compiler was installed in the SYSX directory, where it was granted access to write to any file in this directory. Naturally, the statistics file SYSX/STAT was also located in this directory such that the compiler (SYSX/FORT) could add language feature information. To achieve this, the compiler's privileges were set with a home files license that was allowed by the operating system to write to any file in the SYSX directory. A billing information file SYSX/BILL was also stored in SYSX { due to its sensitive nature, this billing file was not directly accessible to users. However, since the compiler was granted access to the entire SYSX directory, users could subvert their access restrictions on the billing information file by using the compiler like so: SYSX/FORT foo.f -o SYSX/BILL The above user-invoked command to the compiler would allow the compiler to first read the user's source code in foo.f, but then the compiler's privilege to SYSX would cause the SYSX/BILL file to be overwritten with the user's binary. In effect, the compiler is the confused deputy having to reconcile both its own and the user's set of privileges, but unfortunately allows for unintended behavior.