How DANE Strengthens Security for TLS, S/MIME and Other Applications

The Domain Name System (DNS) offers ways to significantly strengthen the security of Internet applications via a new protocol called the DNS-based Authentication of Named Entities (DANE). One problem it helps to solve is how to easily find keys for end users and systems in a secure and scalable manner. It can also help to address well-known vulnerabilities in the public Certification Authority (CA) model. Applications today need to trust a large number of global CAs. There are no scoping or naming constraints for these CAs – each one can issue certificates for any server or client on the Internet, so the weakest CA can compromise the security of the whole system. As described later in this article, DANE can address this vulnerability.


Blue Folder With Keyhole on digital background

Thinking Ahead on Privacy in the Domain Name System

Earlier this year, I wrote about a recent enhancement to privacy in the Domain Name System (DNS) called qname-minimization. Following the principle of minimum disclosure, this enhancement reduces the information content of a DNS query to the minimum necessary to get either an authoritative response from a name server, or a referral to another name server. This is some additional text.

In typical DNS deployments, queries sent to an authoritative name server originate at a recursive name server that acts on behalf of a community of users, for instance, employees at a company or subscribers at an Internet Service Provider (ISP). A recursive name server maintains a cache of previous responses, and only sends queries to an authoritative name server when it doesn’t have a recent response in its cache. As a result, DNS query traffic from a recursive name server to an authoritative name server corresponds to samples of a community’s browsing patterns. Therefore, qname-minimization may be an adequate starting point to address privacy concerns for these exchanges, both in terms of information available to outside parties and to the authoritative name server.


Highlights From vBSDcon: Plenary Talk Videos Now Available

vBSDcon, hosted by Verisign, brought more than 100 attendees from the Berkeley Software Distribution (BSD) community together for a series of plenary talks, educational sessions and networking opportunities earlier this month.

“This biennial conference has been particularly special to us because of the grassroots effort within Verisign to be sure we do our part to help advance BSD,” said Verisign CTO Burt Kaliski.


How Will Your Registration Data Be Managed in the Future?

Benjamin Franklin once said, “By failing to prepare, you are preparing to fail.” As we consider how Internet domain and address registration data is managed and accessed in a post-WHOIS era, and given the long history of failure in addressing the shortcomings of WHOIS, it is extremely important to start preparing now for the eventual replacement of WHOIS. This is the fundamental purpose of the next Registration Operations Workshop (ROW) that is scheduled for Sunday, July 19, 2015, in Prague, Czech Republic.

ROW 2015-2 will take place at the Hilton Prague hotel, the same venue as the 93rd meeting of the Internet Engineering Task Force (IETF-93). The workshop will be dedicated to discussion and planning for development and testing deployments of the Registration Data Access Protocol (RDAP), a recent work product of the IETF that is documented in Request For Comments (RFC) documents 7480, 7481, 7482, 7483, and 7484. RDAP was designed from the beginning to address the many shortcomings of WHOIS, but we have very little experience with early-stage implementations that can be used to inform the policy decisions that need to be made. Additional information about WHOIS and RDAP can be found in my “Where Do Old Protocols Go To Die?” blog post published earlier this year. (more…)

Registration Operations is More Than Just Registering Domain Names

Perceptions can be difficult to change. People see the world through the lens of their own experiences and desires, and new ideas can be difficult to assimilate. Such is the case with the registration ecosystem. Today’s operational models exist because of decisions made over time, but the assumptions that were used to support those decisions can (and should) be continuously challenged to ensure that they are addressing today’s realities. Are we ready to challenge assumptions? Can the operators of registration services do things differently?


Blue Folder With Keyhole on digital background

“What’s in a Name?” Using DANE for Authentication of Internet Services

Do we already have strong security protections for our Internet services? For many years now, we have had numerous cryptographically enhanced protocols. Standards and suites like S/MIME, Transport Layer Security (TLS), IP Security (IPSec), OpenPGP, and many others have been mature for years, have offered us a range of protections and have been implemented by a wealth of code. Indeed, based on these protections, we already count on having “secure” eCommerce transactions, secure point-to-point phone calls that our neighbors can’t listen in on, secure Virtual Private Networks (VPN) that let us remotely connect to our internal enterprise networks, etc.  However, our Internet security protocols have all excluded a very important step from their security analyses; none of them describe a crucial step called secure key learning.  That is, before we can encrypt data or verify signatures, how does someone bootstrap and learn what cryptographic keys are needed?  In lieu of a way to do this, we have traditionally prefaced the security protections from these protocols with techniques like Out of Band (OOB) key learning (learning keys in an unspecified way) or Trust on First Use (ToFU) key learning (just accepting whatever keys are found first), and each protocol must do this separately (and potentially in its own, different, way).  This is because the protocols we use for protections have not formally specified a standardized way to securely bootstrap protocols.


Minimum Disclosure: What Information Does a Name Server Need to Do Its Job?

Two principles in computer security that help bound the impact of a security compromise are the principle of least privilege and the principle of minimum disclosure or need-to-know.

As described by Jerome Saltzer in a July 1974 Communications of the ACM article, Protection and the Control of Information Sharing in Multics, the principle of least privilege states, “Every program and every privileged user should operate using the least amount of privilege necessary to complete the job.”

Need-to-know is the counterpart for sharing information: a system component should be given just enough information to perform its role, and no more. The US Department of Health and Human services adopts this principle in the HIPAA privacy policy, for example, which states: “protected health information should not be used or disclosed when it is not necessary to satisfy a particular purpose or carry out a function.”

There may be tradeoffs, of course, between minimizing the amount of privilege or information given to a component in a system, and other objectives such as performance or simplicity. For instance, a component may be able to do its job more efficiently if given more than the minimum amount.  And it may be easier just to share more than is needed, than to extract out just the minimum required. The minimum amounts of privilege may also be hard to determine exactly, and they might change over time as the system evolves or if it is used in new ways.

Least privilege is well established in DNS through the delegation from one name server to another of just the authority it needs to handle requests within a specific subdomain. The principle of minimum disclosure has come to the forefront recently in the form of a technique called qname-minimization, which aims to improve privacy in the Domain Name System (DNS).


Call for Participation: Registration Operations Workshop at IETF-92

The next Registration Operations Workshop will take place at the start of IETF-92 on Sunday, March 22, 2015, at The Fairmont Dallas Hotel. The workshop will start at 12:30 p.m. CDT and will finish at 4:30 p.m. CDT. We are seeking proposals for Extensible Provisioning Protocol (EPP) extensions to be featured as part of the workshop, including existing extensions that people wish to register with the Internet Assigned Numbers Authority (IANA) and new extensions that people wish to consider for further development.

Have you developed custom EPP extensions in your registry? Please submit a proposal to describe your extension. Facilities for remote participation will be provided.


Where Do Old Protocols Go To Die?

In Ripley Scott’s classic 1982 science fiction film Blade Runner, replicant Roy Batty (portrayed by Rutger Hauer) delivers this soliloquy:

“I’ve…seen things you people wouldn’t believe…Attack ships on fire off the shoulder of Orion. I watched C-beams glitter in the dark near the Tannhäuser Gate. All those…moments…will be lost in time, like (cough) tears…in…rain. Time…to die.”

The WHOIS protocol was first published as RFC 812 in March 1982 – almost 33 years ago. It was designed for use in a simpler time when the community of Internet users was much smaller. WHOIS eventually became the default registration data directory for the Domain Name System (DNS). As interest in domain names and the DNS has grown over time, attempts have been made to add new features to WHOIS. None of these attempts have been successful, and to this day we struggle with trying to make WHOIS do things it was never designed to do.