This is an incompatible change in the output of the tracking command,
which may break some scripts, but it's necessary to avoid confusion with
IPv4 addresses when synchronised to an IPv6 server or reference clock.
Adapt the interleaved symmetric mode for client/server associations.
On server, save the state needed for detection and responding in the
interleaved mode in the client log. On client, enable the interleaved
mode when the server is specified with the xleave option. Always accept
responses in basic mode to allow synchronization with servers that
don't support the interleaved mode, have too many clients, or have
multiple clients behing the same IP address. This is also necessary to
prevent DoS attacks on the client by overwriting or flushing the server
state. Protect the client's state variables against replay attacks as
the timestamps are now needed when processing the subsequent packet.
Enable SCM_TIMESTAMPING control messages and the socket's error queue in
order to receive our transmitted packets with a more accurate transmit
timestamp. Add a new file for Linux-specific NTP I/O and implement
processing of these messages there.
Replace struct timeval with struct timespec as the main data type for
timestamps. This will allow the NTP code to work with timestamps in
nanosecond resolution.
Add support for authenticating MS-SNTP responses in Samba (ntp_signd).
Supported is currently only the old MS-SNTP authenticator field. It's
disabled by default. It can be enabled with the --enable-ntp-signd
configure option and the ntpsigndsocket directive, which specifies the
location of the Samba ntp_signd socket.
Use REF_GetReferenceParams() in the tracking command to simplify the
code and report the same values as what NTP clients of the server see.
When the local reference mode is active, this changes the leap status to
synchronised and reference time to one second behind current time. When
not synchronised, the root delay and root dispersion are now 1 second.
Add a new printf-like function to allow printing of all fields at once
and rework all commands which print a report to use it. Add functions
for printing of headers and information fields, and formatting of IP
addresses and reference IDs.
Remove automatic download and compilation of clknetsim. If clknetsim is
not found, skip all simulation tests, but don't fail "make check".
Also, respect the CLKNETSIM_PATH environment variable.
Since commit 8b235297, which changed address hashing, the first packet
is not sent to the first server and doesn't have the extra delay. If the
last packet is sent to the first server, the mean outgoing interval will
be significantly longer than the incoming interval and the check will
fail.
Include a test program to determine how the adjtime() implementation
behaves. Check the range of supported offset, support for readonly
operation, and slew rate with different update intervals and offsets.
Also, add a test for ntp_adjtime() to check what frequency range it
supports.
Add maxdistance directive to set the maximum root distance the sources
are allowed to have to be selected. This is useful to reject NTPv4
sources that are no longer synchronized and report large dispersion.
The default value is 3 seconds.
The leaponly option can be used to enable a mode where only leap seconds
are smoothed out and normal offset/frequency changes are ignored. This
is useful to make the interval in which a leap second is smoothed out
constant and allow an NTP client to use multiple leap smearing servers
safely.
