Refactor and Upgrade ntpd’s Extension Field Handling

Refactor and Upgrade ntpd’s Extension Field Handling

2022 ARIN Community Grant Program Recipient Report

Network Time Foundation (NTF) received an ARIN Community Grant in 2022 to align the Network Time Protocol (NTP) Project’s Reference Implementation with evolving standards while preserving legacy compatibility. Autokey, a significant feature of NTPv4 introduced in 1997, had gained prominence in the NTP community, culminating with the publication of the NTPv4 Standards in 2010. However, the project needed to reconcile discrepancies between the legacy codebase and the updated Extension Field headers.

Autokey was replaced with Network Time Security (NTS), and, to support both Autokey users and evolving standards, we began the complex task of reconciling Extension Field formats. The grant enabled the integration of the previous Extension Field work with the current codebase. Rigorous testing ensured that this integration did not introduce bugs. The effort involved 126 changed files, 1,089 lines of code, and 30,283 characters.

Learn more about all the 2022 ARIN Community Grant Program Recipients.

Impact of the Project

While a limited audience has seen this effort’s immediate impact, its inclusion in the Reference Implementation of NTP will soon be seen and used by millions of users, given that the NTP Project’s NTP software has been the gold standard for synchronized time since the 1980s. We anticipate widespread adoption of ntp-4.4 upon its release.

Our focus on NTS — our most asked-for feature — addresses a crucial industry need, benefiting reference clock vendors, operating system (OS) vendors, enterprise users, NTP Pool operators, and the broader NTP community. The improvements in ntp-4.4 are expected to incentivize users to upgrade by offering improved time synchronization, enhanced security, and reduced NTP-related distributed denial-of-service (DDoS) vulnerabilities.

NTF used the ARIN 2022 Community Grant to achieve a significant milestone in the evolution of NTP, driven by a commitment to modernize while honoring legacy users. The grant was pivotal in achieving these outcomes, ensuring that ntp-4.4 will deliver enhanced time synchronization, security, and reliability to the global Internet community.

Watch the video presentation of NTF’s project update on YouTube. 

What’s Next?

The grant funding enabled this key stage of our work to be completed, and we are very happy to say that the results will enable us to complete and deliver the next major release of the Reference Implementation of NTP, ntp-4.4. To do so, we’ll merge this work into the ntp-dev code branch, release ntp-4.2.8p18 (without this work), engage testers with ntp-dev, and ultimately finalize ntp-4.4.

About the ARIN Community Grant Program

ARIN provides financial grants in support of initiatives that improve the overall Internet industry and Internet user environment. Are you working on a project that advances ARIN’s mission and broadly benefits the Internet community within the ARIN region through informational outreach, research, Internet technical improvements, or Registry processes and technology improvements? Visit the ARIN Community Grant Program page for more information and to find out how your organization can apply in 2024. For application tips and support, read this post on our blog.

Post written by:

Harlan Stenn
President, Network Time Foundation, Inc.

Harlan Stenn began programming computers in 1971. He holds a bachelors degree in Business Administration (Accounting) from The Colorado College in Colorado Springs, and an MSE in Computer Science from Washington University in St. Louis.

A well-versed entrepreneur, Harlan has launched several successful businesses and has been a respected, sought-after I/T consultant and contractor for decades. At some point during the 1980s, he started using and submitting bug fixes and portability improvements to the Network Time Protocol codebase. He has worked directly with NTP since 1992, and in 1996 became NTP’s Project Manager and Release Engineer. In 2011 he created Network Time Foundation to provide bring together and nurture collaborative Open Source projects that focus on Network Time. The first project to join was, of course, the NTP Project. Shortly thereafter the PTPd, RADclock and Linux PTP projects joined. Since then Harlan has been managing NTF’s progress in the first implementation of the Network Time Security draft IETF specification, driving NTF’s General Timestamp API Project, and incorporating the Ntimed Project into NTF.

Any views, positions, statements, or opinions of a guest blog post are those of the author alone and do not represent those of ARIN. ARIN does not guarantee the accuracy, completeness, or validity of any claims or statements, nor shall ARIN be liable for any representations, omissions, or errors contained in a guest blog post.

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