Release Notes

Version 4.1 - September 2023

This release is the first of our regular quarterly releases. It includes a new feature (multi-domain synchronization for phc2sys) and several minor bug fixes. Users are encouraged to upgrade.

Version 4.0 - June 2023

This release includes both new and improved features and many minor bug fixes. Users are encouraged to upgrade. The most notable changes are as follows.

• Officially supports the 2019 version of IEEE 1588.
• Improved unicast messaging
• Enhanced G.8275.2 profile
• More flexible Pulse Per Second (PPS) handling
• Virtual clock support
• Power profile support
• VLAN over bond support.
• Parallel Redundancy Protocol (PRP) trailer handling.
• Non-privileged read-only monitoring port.
• New statistics reporting.

Version 3.1.1

Fixes:

• CVE-2021-3570 linuxptp: missing length check of forwarded messages
• CVE-2021-3571 linuxptp: wrong length of one-step follow-up in transparent clock

Version 3.1 - September 2020 (superseded)

This release offers substantial new functionality. Users are encouraged to upgrade. The most notable changes are as follows.

• Fixes non-functional NMEA mode of the ts2phc program (since 3.0)
• Improves system time synchronization via the PTP_SYS_OFFSET_PRECISE and PTP_SYS_OFFSET_EXTENDED ioctls.
• Supports implementing a PTP GM clock by using a GPS radio or other PPS time source.
• Provides per-port statistics via the management interface.
• Implements IEEE 1588 v2.1 slave event monitoring.
• Adds Automotive Profile support.

Version 3.0 - superseded by version 3.1

Version 2.0.1

Fixes:

• CVE-2021-3570 linuxptp: missing length check of forwarded messages
• CVE-2021-3571 linuxptp: wrong length of one-step follow-up in transparent clock

Version 2.0 - August 2018 (superseded)

This release represents a major new milestone, and it includes substantial new features. Users are encouraged to upgrade. The most notable changes are as follows.

• Peer-to-Peer Transparent Clock support
• End-to-End Transparent Clock support
• Unicast support
• Support for all three Telecom Profiles
  • T-REC-G.8265.1-201407
  • T-REC-G.8275.1-201606
  • T-REC-G.8275.2-201708

Version 1.9.3

Fixes: CVE-2021-3570 linuxptp: missing length check of forwarded messages

Version 1.9.2 - April 2018 (superseded)

This release is an incremental improvement to the previous version, and it includes both bug fixes and major new features. Users are strongly encouraged to upgrade. The most notable changes are as follows.

• Fixed stack buffer overflow in the new NetSync Monitor code (since 1.9)
• Command line support for every configuration variable via long options
• IPoIB interface support
• Improved Delay Request performance at high message rates
• Improved UTC offset tracking
• Multiple TLV support
• NetSync Monitor protocol support
• Peer to peer one-step
• Support for bonded interfaces

Version 1.9.1 - superseded by version 1.9.2

Version 1.9 - superseded by version 1.9.2

Version 1.8.1

Fixes: CVE-2021-3570 linuxptp: missing length check of forwarded messages

Version 1.8 - November 2016 (superseded)

This release fixes a regression in the previous version and a bug that been there all along:

• Fix regression in one-step configuration.
• Fix input to the BMC for forming the spanning tree.

In addition, there is one new feature. The program now monitors the link state of the ports and reacts to the link going up or down in a more intelligent way.

Version 1.7.1

Fixes: CVE-2021-3570 linuxptp: missing length check of forwarded messages

Version 1.7 - July 2016 (superseded)

This release fixes a regression in the previous version. It also includes a few bug fixes and one new feature, namely an option to support DSCP values on UDP message. There are two important bug fixes.

• Prevent unintentional closing of the UDS port.
• Fix the P2P handling when the peer operates in one shot mode.

Version 1.6.1

Fixes: CVE-2021-3570 linuxptp: missing length check of forwarded messages

Version 1.6 - September 2015 (superseded)

This release is an incremental improvement to the previous one, and it includes two new features and a few bug fixes. Users are encouraged to upgrade. The most notable changes are as follows.

• Support for the hybrid unicast/multicast delay mechanism from the draft Enterprise Profile.
• Modular time stamp processing including a mode for jittery networks.

Version 1.5.1

Fixes: CVE-2021-3570 linuxptp: missing length check of forwarded messages

Version 1.5 - December 2014 (superseded)

This release is an incremental improvement to the previous version, including many new features and several bug fixes. Users are encouraged to upgrade. The most notable changes are as follows.

• Adaptive servo based on linear regression.
• Automatic configuration for the phc2sys program.
• Event subscribing and notification.
• Improved transmit time stamp performance.
• Leap second and TAI offset handling.
• New phc_ctl and timemaster utility programs.
• Peer delay calculation adjustment using neighborRateRatio.
• Poor man's Boundary Clock using a heterogeneous set of devices.
• Servo for NTP SHM reference clock.

Version 1.4 - February 2014 (withdrawn)

This release includes bug fixes and improved protocol support, and it is an incremental improvement to the previous version. Users are strongly encouraged to upgrade. The most notable changes are as follows.

• Median filter on the delay estimates
• Improved gPTP support, including the gmCapable flag
• Various minor corrections to the protocol handling
• Multiple ptp4l instances can each have their own unix domain socket
• Better run time error checks and messages
• Expanded compile time error checking
• Documentation enhancements

Version 1.3 - August 2013 (withdrawn)

This release is an incremental improvement to the previous version, and it includes both bug fixes and new features. Users are strongly encouraged to upgrade. The most notable changes are as follows.

• Automatic adjustment of PI servo constants according to sync interval.
• Fix bug in unlucky sync/follow up handling.
• Improved grand master support.
• New servo option which specifies first step threshold.
• Stricter configuration value validation.
• Support management messages according to IEEE 1588 interpretation #29.
• Use a dynamic frequency estimation interval.
• Numerous documentation improvements and small bug fixes.

Version 1.2 - April 2013 (withdrawn)

This release is an incremental improvement to the previous version, and it includes both bug fixes and new features. This version introduces a change that is incompatible with existing configuration files. The 'tx_timestamp_retries' configuration variable has been removed, and custom config files must be adjusted accordingly. Users are encouraged to upgrade. The most notable changes are as follows.

• Automatically enabled PPS output from a PTP Hardware Clock.
• CLOCK_DESCRIPTION and USER_DESCRIPTION management messages.
• Fixed message alignment for armv5 machines.
• Leap second handling.
• More reliable transmit time stamps.
• Support multiple fault types.

Version 1.1 - February 2013 (withdrawn)

This release is an incremental improvement to the previous version, and it includes both bug fixes and new features. Users are strongly encouraged to upgrade. The most notable changes are as follows.

• Added "asCapable" logic according to 802.1AS.
• Better responses to management message errors.
• Corrected the peer delay message timer for P2P mode.
• Fixed bugs in TLV handling.
• Improved servo start up performance.
• New logging option to show synchronization summary.
• Numerous improvements to the phc2sys program.

Version 1.0 - December 2012 (withdrawn)

This is the first official release. It includes the following features.

• Hardware and software time stamping.
• Linux PTP Hardware Clock (PHC) subsystem, and synchronizing the system clock to it.
• Boundary Clock and Ordinary Clock.
• IEEE 802.1AS-2011 in the role of end station.
• Transport over UDP/IPv4, UDP/IPv6, and raw Ethernet (Layer 2 and VLAN).
• Profile configuration via INI like files.
• Reading out of the data sets via management messages.
• Local IPC via UNIX Domain Sockets.
• Simple management client.
• Path trace TLV.
• Man pages.