The sample time used in calculation of the last_meas_ago (LastRx) value
in the sources report is aligned to the second to minimize the leak
of the NTP receive timestamp, which could be useful in some attacks.
There is no need to do that with reference clocks, which are often used
with very short polling intervals and an extra second in the LastRx
value can be misinterpreted as a missed sample.
Don't leave the variables set to values outside their effective range.
This has no functional impact, but makes it clear what is the precedence
of the two settings.
When loading a dump file with the -r option, check also sanity of the
sample time, offset, peer/root delay/dispersion, and the sample order to
better handle corrupted files.
Check for write errors when saving dump files. Don't save files with no
samples. Add more sanity checks for loaded data.
Extend the file format to include an identifier, the reachability
register, leap status, name, and authentication flag. Avoid loading
unauthenticated data after switching authentication on. Change format
and order of some fields to simplify parsing. Drop fields that were kept
only for compatibility.
The dump files now contain all information needed to perform the source
selection and update the reference.
There is no support kept for the old file format. Loading of old dump
files will fail after upgrading to new version.
Setting maxsamples to 1 or 2 prevented the source from being selected as
the regression would always fail. Handle this as a special case with
disabled frequency tracking in order to enable a fast reference update
with the -q/-Q option.
If there are too few samples to make a regression, at least update the
offset estimate from the last sample and keep the previous frequency
offset unchanged. Also, reset the error estimates.
This moves the leap status of the last sample from the source instance
to the sourcestats instance in order to make them both accumulate the
same data.
Instead of giving NTP-specific data to sourcestats in order to perform
the test, provide a function to get all data needed for the test in
ntp_core. While at it, improve the naming of variables.
If the minimum delay is known (in a static network configuration), it
can replace the measured minimum from the register. This should improve
the stability of corrections for asymmetric jitter, sample weighting and
maxdelay* tests.
In order to stabilize the weights of refclock samples which have only
slightly different distances, don't allow the stddev value used in the
weight calculation to be smaller than the precision and also assign
weight of 1 to all samples which have distance < minimum + precision.
Source selection uses the last event time as current time. If it was
called from a refclock which generates a sample in its poll function
(e.g. PHC), the sample time may be later than the event time. This
gives a negative elapsed time in SST_GetSelectionData() and possibly
also a negative root distance, which causes the source to be rejected as
a falseticker.
Use absolute value of the difference in order to always get a positive
root distance.
It was never used for anything and messages in debug output already
include filenames, which can be easily grepped if there is a need
to see log messages only from a particular file.
This reduces leak of sample times (and receive timestamps which are
related to sample times), which could be useful in off-path attacks on
unauthenticated symmetric interleaved mode.
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.
