NTP Patches After 4.2.8p18

After the release of NTP-4.2.8p18, Dave Hart hart@ntp.org implemented some useful patches that have been incorporated
into the NTP code base used by Meinberg in current LANTIME firmware versions and in the NTP installer for Windows.

Patches that improve the behavior of the NTP daemon:

• [Bug 3943] 4.2.8p18 ignores link-local IPv6 server.

• [Bug 3940] ntpd 4.2.8p18 regression from p17 for digests longer than 160 bits, e.g. SHA256-type MACs.

• [Bug 3932] Ignore teredo interfaces in Windows ntpd.

• [Bug 3928] ntpd 4.2.8p18 crash when bringing up net interface fails.

• [Bug 3925] ntpd on Windows 8 and later doesn't set CMOS clock at shutdown.

• [Bug 3924] Windows ntpd gives up on DNS too quickly at OS startup.
  Increase max. DNS retry interval from 32 to 1024 seconds.

• [Bug 3877] 4.2.8p16 client rejects server response with zero ppoll, e.g. from 3rd party NTP implementations.

• Display SSL shared library version number in human form.

Patches that improve compilation of the source code:

• [Bug 3942] DECL_SYSCALL detection does not work on illumos.

• [Bug 3933] Restrict structure misaligned on SPARC64.

• [Bug 3931] Libopts is not respecting VPATH.

• [Bug 3930] Windows build mkver.bat races itself.

• [Bug 3929] 4.2.8p18 -Werror -Wincompatible-pointer-types breaks w/md5.h.
  Wrap MD5Update() calls for varying declarations.

• [Bug 3927] 4.2.8p18 configure reverses -L and -l in $LIBS for OpenSSL test.

• [Bug 3926] pthread_detach() not detected with gcc 14, clang 16.
  Use pthread_t arg in openldap-thread-check.m4.

• Reorder restrict_u layout to improve alignment on all platforms.

• Correct match_restrict[46]_addr() logic expiring temporary restrictions.

• Rename is_ip_address() to sau_from_string() to better reflect use.

• Remove include/safecast.h

• Fix bug in m4sh macro NTP_FACILITYNAMES that meant detection always failed.

— Martin Burnicki martin.burnicki@meinberg.de, last updated 2025-09-22