Welcome!

Linux Containers Authors: Liz McMillan, Pat Romanski, Elizabeth White, Yeshim Deniz, Roger Strukhoff

Related Topics: Linux Containers

Linux Containers: Article

Trusting Computing on Linux

Building a trusted platform

In an era where everybody is connected to a potentially harmful Internet with an increasing number of complex and distributed applications, controlling what the computers do has become significantly harder. At the core, simple actions (executing software, e-commerce, etc.) rely on trust relationships; what if your computer (or the merchant's) has been compromised and alters your perception of reality? Indeed, at the beginning, Neo did not know there was a Matrix because he trusted everything he saw...

Closer to our world, and without being paranoid, one of the first actions intruders or rootkits take is to replace common commands with fake ones. Is it then possible to guarantee that we'll really execute the code we intended to? How far can you trust the computer of a given merchant not to reveal your credit card number? This is precisely what trusted computing is about: providing the means to know how much a given machine may be trusted.

Actually, the use of chips to enforce security within the lowest layers isn't new; it's existed for many years. However, their high price, difficult integration with commercial software, and high impact on systems' performances has restricted their use to the mainstream industry.

Several major industrials decided to join their efforts and design a compromise that would meet market needs. The idea was to build a trusted platform, including a new security chip, that would be easier to use and with more computational power, but perhaps a little less secure. They first gave birth to the TCPA (Trusted Computing Platform Alliance) in 1999, and then to its successor, TCG (Trusted Computing Group), in 2003.

Trusted Computing Group

The primary goal of the TCG is to provide the industry with vendor-neutral standard specifications for various platforms (PC, PDA, mobile phone, etc.). To do so, they describe a subsystem to integrate onto each platform and that provides protection to a user's computing environment, and information and keys to operating systems or applications. More precisely, TCG's proposed subsystem consists of a Trusted Platform Module (TPM) and the TPM Software Stack (TSS).

The TPM is a hardware chip. It provides low-level trusted computing functionalities such as protected storage (making sure encryption keys cannot be retrieved even if the platform is compromised), integrity metrics (detecting compromise), and platform attestation (prove to others that the platform has a given property).

As for the TSS, it's organized as shown in Figure 1:

  • A TPM device driver, typically provided by the TPM manufacturer
  • An abstraction layer to TPM drivers, the TDDL, which makes it possible to develop upper components in the stack independent of the TPM chip
  • A core services layer (TCS) that groups all common services to the software stack, such as event management, key and credentials management, etc.
  • Various TSS Service Providers (TSP) that, for example, offer access to specific APIs such as PKCS#11
To illustrate the possible benefits of using trusted compu-ting, let's describe a simple case where a system administrator needs to secure an employee's laptop access to the corporate network. The employee accesses his or her company's network using a secret key and specific network access software (e.g., a VPN client). The problem is that the employee's laptop is obviously untrusted; it's carried everywhere and unfortunately is the ideal target for viruses or any other malware. If a laptop's corporate network access software and/or the secret key are compromised, this may seriously impact corporate security.

To avoid such a scenario, a possible solution relies on trusted computing. The administrator uses the TPM to seal the secret key with the BIOS, OS, and the network access software. This cryptographically binds the keys to a given software stack, so that only the TPM may unseal the key if and only if the software stack (BIOS, OS, network-access software) has not been compromised. This virtually establishes trust on an untrusted platform.

Linux Support for TCG

In practice, TPMs are already well established on the market, although perhaps not that widely yet. Several chip manufacturers propose TPM chips (e.g., Infineon's SLD 9630 TT or Atmel's AT97SC3201). Intel has developed TPM-integrated boards (D865GRH, D915GEV, and D915GUX desktop boards). TPMs are even sold on a specific desktop or laptop series (IBM ThinkCentre, HP Compaq DC7100, Toshiba Tecra M2, Fujitsu Lifebook S, etc.). The real difficulty in getting your hands on TCG arises later, within the TPM Software Stack. Indeed, mainstream Linux kernels do not natively recognize TPM chips, and solutions to use them are nearly nonexistent at the moment.

With Linux, we are presently only aware of NTRU's TSS and a few research projects listed in Table 1. Most of those are highly experimental, with only limited support of TPM chips and a selected subset of TCG functions. Clearly, this is currently only a developer's or an expert's world; there is no way an end user can benefit from TCG's functionalities without getting into the source code.

TCG and Linux

Actually, trusted computing's first exposure to the public has been quite controversial. Basically, people worried that this technology would scorn privacy or block software interoperability. Others even exposed startling side effects. The reality is probably somewhat more balanced, and we dare to compare trusted computing to a Swiss army knife: it can be extremely useful for getting out of (dangerous?) situations, but obviously it may be lethal.

It's beyond the scope of this article to tackle privacy and TCG issues in more detail, though we invite interested readers to refer to the resources section for further readings.

Whether we want it or not, trusted computing seems to be a part of the future for many commercial systems. Support for TCG is already part of the requirements for some industrial Linux systems. Market perspective looks extremely promising; indeed, there are still several research and development opportunities:

  • At the hardware level, by introducing new trusted hardware on the market (see for instance, Intel's trusted keyboard controller).
  • At the operating system level, with a new "trusted" OS making use of trusted hardware. This would probably consist of a kernel module but with a broader link to the OS.
  • At the application level, with numerous use cases for end-user "trusted" applications, but barely any implementation on Linux yet.
  • In the area of embedded systems - for example, mobile phones, PDAs, or other devices.

Conclusion

Currently, the best way to qualify TCG's penetration in the market is moderate: the TPM chips are already on the market, but their software stack is extremely limited and experimental. Yet, whatever your rationale is - for or against TCG technology - with the widespread propagation of viruses and other malware, and the ever-increasing security needs of the industry, trusted computing seems an extremely promising technology and TPM chips are very likely to be deployed more frequently on systems around us. It would then be extremely positive for the Linux community - and more generally the open source community - to get involved. Indeed, how much and how well TPMs are supported and integrated could become a selection criteria among operating systems in the future.

Resources

  • Yee, B. "Using Secure Coprocessors", PhD Thesis, CMUCS94149, May 1994: http://citeseer.ist.psu.edu/yee94using.htm
  • Arnold, T. W., and van Doorn, L. P. "The IBM PCIXCC: A new cryptographic coprocessor for the IBM eServer." IBM Research & Development Journal. Vol. 48, No. 3. May/July 2004.
  • Trusted Computing Group: www.trustedcomputinggroup.org
  • NTRU Core TCG Software Stack (CTSS): www.ntru.com/products/tcg_ss.htm
  • Safford, D. "TCPA Resources": www.research.ibm.com/gsal/tcpa/
  • Sailer, R.; Jaeger, T.; van Doorn, L.; Zheng, X. "TPM based Linux Runtime Attestation": www.research.ibm.com/secure_systems_department/projects/tcglinux/
  • Wild, O., and Marchesini, J. "Enforcer": http://enforcer.sourceforge.net/
  • Sevinc, P.E. "A Software-based TPM Emulator for Linux": www.infsec.ethz.ch/people/psevinc
  • Selhorst, M., and Stueble, C. "Linux Kernel Module for the Infineon Trusted Platform Module SLD 9630 TT": www.prosec.rub.de/tpm/
  • Anderson, R. "Trusted Computing - Frequently Asked Questions", version 1.1. August 2003: www.againsttcpa.com/tcpafaqen.html
  • Schechter, S.E.; Greenstadt, R.A.; and Smith, M.D. "Trusted Computing, Peer to Peer Distribution, and the Economics of Pirated Entertainment." Second Workshop on Economics and Information Society, May 29, 2003: www.eecs.harvard.edu/~stuart/papers/eis03.pdf
  • Carrier Grade Linux Hardware Requirements definition version 3: www.osdl.org/docs/cgl_hw_req_def___v30_draft.pdf
  • Bajikar, S. "Trusted Mobile Keyboard Controller Architecture." Intel Developers Forum. Fall 2003: www.intel.com/idf/us/fall2003/presentations/F03USMOBS147_OS.pdf
  • Wave Systems, Embassy Trust Suite: www.wave.com/products/ets_pro.html
  • Linux Devices. January 22, 2003: www.linuxdevices.com/news/NS9222005703.html
  • Walko, J. "ARM links with Trusted Logic for secure mobile, set tops." July 14, 2004: www.embedded.com/showArticle.jhtml?articleID=23900682&_loopback=1
  • More Stories By Makan Pourzandi

    Makan Pourzandi received his doctoral degree on parallel computing in 1995 from the University of Lyon, France. He works for Ericsson Research
    Canada in the Open Systems Research Department. His research domains are security, cluster computing, and component-based methods for
    distributed programming. He has more than 7 publications in International conferences with reference committees. Makan has delivered several talks
    at universities, international conferences, and Open Source forums. He is involved in several Open Source projects: Distributed Security
    Infrastructure (disec.sourceforge.net), and a contributer to the
    security requirements of the Open Source Development Lab (OSDL) Carrier Grade Linux (CGL).

    More Stories By Axelle Apvrille

    Axelle Apvrille currently works for Ericsson Research Canada in the Open Systems Research Department. Her
    research interests are cryptography, security protocols and distributed
    security. She received her computer science engineering degree in 1996
    at ENSEIRB, Bordeaux, France.

    Comments (0)

    Share your thoughts on this story.

    Add your comment
    You must be signed in to add a comment. Sign-in | Register

    In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


    @ThingsExpo Stories
    In his Opening Keynote at 21st Cloud Expo, John Considine, General Manager of IBM Cloud Infrastructure, led attendees through the exciting evolution of the cloud. He looked at this major disruption from the perspective of technology, business models, and what this means for enterprises of all sizes. John Considine is General Manager of Cloud Infrastructure Services at IBM. In that role he is responsible for leading IBM’s public cloud infrastructure including strategy, development, and offering m...
    SYS-CON Events announced today that Evatronix will exhibit at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Evatronix SA offers comprehensive solutions in the design and implementation of electronic systems, in CAD / CAM deployment, and also is a designer and manufacturer of advanced 3D scanners for professional applications.
    SYS-CON Events announced today that Synametrics Technologies will exhibit at SYS-CON's 22nd International Cloud Expo®, which will take place on June 5-7, 2018, at the Javits Center in New York, NY. Synametrics Technologies is a privately held company based in Plainsboro, New Jersey that has been providing solutions for the developer community since 1997. Based on the success of its initial product offerings such as WinSQL, Xeams, SynaMan and Syncrify, Synametrics continues to create and hone inn...
    To get the most out of their data, successful companies are not focusing on queries and data lakes, they are actively integrating analytics into their operations with a data-first application development approach. Real-time adjustments to improve revenues, reduce costs, or mitigate risk rely on applications that minimize latency on a variety of data sources. In his session at @BigDataExpo, Jack Norris, Senior Vice President, Data and Applications at MapR Technologies, reviewed best practices to ...
    "Evatronix provides design services to companies that need to integrate the IoT technology in their products but they don't necessarily have the expertise, knowledge and design team to do so," explained Adam Morawiec, VP of Business Development at Evatronix, in this SYS-CON.tv interview at @ThingsExpo, held Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA.
    Digital Transformation (DX) is not a "one-size-fits all" strategy. Each organization needs to develop its own unique, long-term DX plan. It must do so by realizing that we now live in a data-driven age, and that technologies such as Cloud Computing, Big Data, the IoT, Cognitive Computing, and Blockchain are only tools. In her general session at 21st Cloud Expo, Rebecca Wanta explained how the strategy must focus on DX and include a commitment from top management to create great IT jobs, monitor ...
    No hype cycles or predictions of a gazillion things here. IoT is here. You get it. You know your business and have great ideas for a business transformation strategy. What comes next? Time to make it happen. In his session at @ThingsExpo, Jay Mason, an Associate Partner of Analytics, IoT & Cybersecurity at M&S Consulting, presented a step-by-step plan to develop your technology implementation strategy. He also discussed the evaluation of communication standards and IoT messaging protocols, data...
    Recently, WebRTC has a lot of eyes from market. The use cases of WebRTC are expanding - video chat, online education, online health care etc. Not only for human-to-human communication, but also IoT use cases such as machine to human use cases can be seen recently. One of the typical use-case is remote camera monitoring. With WebRTC, people can have interoperability and flexibility for deploying monitoring service. However, the benefit of WebRTC for IoT is not only its convenience and interopera...
    Product connectivity goes hand and hand these days with increased use of personal data. New IoT devices are becoming more personalized than ever before. In his session at 22nd Cloud Expo | DXWorld Expo, Nicolas Fierro, CEO of MIMIR Blockchain Solutions, will discuss how in order to protect your data and privacy, IoT applications need to embrace Blockchain technology for a new level of product security never before seen - or needed.
    Recently, REAN Cloud built a digital concierge for a North Carolina hospital that had observed that most patient call button questions were repetitive. In addition, the paper-based process used to measure patient health metrics was laborious, not in real-time and sometimes error-prone. In their session at 21st Cloud Expo, Sean Finnerty, Executive Director, Practice Lead, Health Care & Life Science at REAN Cloud, and Dr. S.P.T. Krishnan, Principal Architect at REAN Cloud, discussed how they built...
    Nordstrom is transforming the way that they do business and the cloud is the key to enabling speed and hyper personalized customer experiences. In his session at 21st Cloud Expo, Ken Schow, VP of Engineering at Nordstrom, discussed some of the key learnings and common pitfalls of large enterprises moving to the cloud. This includes strategies around choosing a cloud provider(s), architecture, and lessons learned. In addition, he covered some of the best practices for structured team migration an...
    The 22nd International Cloud Expo | 1st DXWorld Expo has announced that its Call for Papers is open. Cloud Expo | DXWorld Expo, to be held June 5-7, 2018, at the Javits Center in New York, NY, brings together Cloud Computing, Digital Transformation, Big Data, Internet of Things, DevOps, Machine Learning and WebRTC to one location. With cloud computing driving a higher percentage of enterprise IT budgets every year, it becomes increasingly important to plant your flag in this fast-expanding busin...
    "Digital transformation - what we knew about it in the past has been redefined. Automation is going to play such a huge role in that because the culture, the technology, and the business operations are being shifted now," stated Brian Boeggeman, VP of Alliances & Partnerships at Ayehu, in this SYS-CON.tv interview at 21st Cloud Expo, held Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA.
    In his session at 21st Cloud Expo, Raju Shreewastava, founder of Big Data Trunk, provided a fun and simple way to introduce Machine Leaning to anyone and everyone. He solved a machine learning problem and demonstrated an easy way to be able to do machine learning without even coding. Raju Shreewastava is the founder of Big Data Trunk (www.BigDataTrunk.com), a Big Data Training and consulting firm with offices in the United States. He previously led the data warehouse/business intelligence and B...
    A strange thing is happening along the way to the Internet of Things, namely far too many devices to work with and manage. It has become clear that we'll need much higher efficiency user experiences that can allow us to more easily and scalably work with the thousands of devices that will soon be in each of our lives. Enter the conversational interface revolution, combining bots we can literally talk with, gesture to, and even direct with our thoughts, with embedded artificial intelligence, whic...
    Cloud Expo | DXWorld Expo have announced the conference tracks for Cloud Expo 2018. Cloud Expo will be held June 5-7, 2018, at the Javits Center in New York City, and November 6-8, 2018, at the Santa Clara Convention Center, Santa Clara, CA. Digital Transformation (DX) is a major focus with the introduction of DX Expo within the program. Successful transformation requires a laser focus on being data-driven and on using all the tools available that enable transformation if they plan to survive ov...
    Smart cities have the potential to change our lives at so many levels for citizens: less pollution, reduced parking obstacles, better health, education and more energy savings. Real-time data streaming and the Internet of Things (IoT) possess the power to turn this vision into a reality. However, most organizations today are building their data infrastructure to focus solely on addressing immediate business needs vs. a platform capable of quickly adapting emerging technologies to address future ...
    With tough new regulations coming to Europe on data privacy in May 2018, Calligo will explain why in reality the effect is global and transforms how you consider critical data. EU GDPR fundamentally rewrites the rules for cloud, Big Data and IoT. In his session at 21st Cloud Expo, Adam Ryan, Vice President and General Manager EMEA at Calligo, examined the regulations and provided insight on how it affects technology, challenges the established rules and will usher in new levels of diligence arou...
    22nd International Cloud Expo, taking place June 5-7, 2018, at the Javits Center in New York City, NY, and co-located with the 1st DXWorld Expo will feature technical sessions from a rock star conference faculty and the leading industry players in the world. Cloud computing is now being embraced by a majority of enterprises of all sizes. Yesterday's debate about public vs. private has transformed into the reality of hybrid cloud: a recent survey shows that 74% of enterprises have a hybrid cloud ...
    22nd International Cloud Expo, taking place June 5-7, 2018, at the Javits Center in New York City, NY, and co-located with the 1st DXWorld Expo will feature technical sessions from a rock star conference faculty and the leading industry players in the world. Cloud computing is now being embraced by a majority of enterprises of all sizes. Yesterday's debate about public vs. private has transformed into the reality of hybrid cloud: a recent survey shows that 74% of enterprises have a hybrid cloud ...