If a SHM or PHC refclock has a very large offset compensated by the
offset option, or ignored with the pps or local option, there is a
persistent loss of precision in the calculation of the sample offset
using the double format.
Rework the code to delay the calculation of the accumulated offset to
include the specificed compensation and remaining correction of the
system clock, where the calculation can be split to improve the
precision. In the pps mode ignore integer seconds competely.
The precision of the SOCK refclock is now limited to 1 nanosecond due to
the extra double->timespec->double conversion.
Add "local" option to specify that the reference clock is an
unsynchronized clock which is more stable than the system clock (e.g.
TCXO, OCXO, or atomic clock) and it should be used as a local standard
to stabilize the system clock.
Handle the local refclock as a PPS refclock locked to itself which gives
the unsynchronized status to be ignored in the source selection. Wait
for the refclock to get at least minsamples samples and adjust the clock
directly to follow changes in the refclock's sourcestats frequency and
offset.
There should be at most one refclock specified with this option.
Add support for accumulating frequency and time offset without changing
the reference parameters and calling the local parameter change
handlers.
This will allow an unsynchronized source to operate below other sources
in order to stabilize the clock.
Allow sources to accumulate samples with the leap status set to not
synchronized. Define a new state for them to be ignored in the
selection. This is intended for sources that are never synchronized and
will be used only for stabilization.
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.
Run the chronyc onoffline command also when the connectivity-change
and dhcp6-change actions are reported by the NetworkManager dispatcher.
The latter should not be necessary, but there currently doesn't seem to
be any action for IPv6 becoming routable after duplicate address
detection, so at least in networks using DHCPv6, IPv6 NTP servers should
not be stuck in the offline state from a previously reported action.
Latest NetworkManager code provides NTP servers from the DHCPv6 NTP
option (RFC 5908) in the DHCP6_DHCP6_NTP_SERVERS variable to dispatcher
scripts.
Check for invalid characters (which can come from the FQDN suboption)
and include the servers in the interface-specific sources file.
If chronyc waitsync was started before chronyd, it would try all
addresses (Unix socket, IPv4, IPv6) and get stuck with no address, not
getting any response later when chronyd was running.
Reset the address index in open_io() when returning with failure to
allow the next call to start with the first address again.
Reported-by: Jan Mikkelsen <janm@transactionware.com>
Fix the FreeBSD-specific code checking for a bound IPv4 socket to
include the new PTP port. This should fix a multihomed server to respond
to NTP-over-PTP requests from the address which received the request.
Fixes: be3158c4e5 ("ntp: add support for NTP over PTP")
In the FreeBSD-specific code checking for a bound IPv4 socket, make
sure it is not a Unix domain address to avoid reading uninitialized
IP-specific fields.
This fixes an error reported by valgrind.
Zero the whole sockaddr struct before calling bind() and connect() to
initialize the FreeBSD-specific sa_len field.
This fixes errors reported by valgrind.
Avoid searching the hash table of sources when a packet in the client
mode is received. It cannot be a response from our source. Analogously,
avoid source lookups for transmitted packets in the server mode. This
doesn't change anything for packets in symmetric modes, which can be
requests and responses at the same time.
This slightly improves the maximum packet rate handled as a server.
For a long time, the Solaris support in chrony wasn't tested on a real
Solaris system, but on illumos/OpenIndiana, which was forked from
OpenSolaris when it was discontinued in 2010.
While Solaris and illumos might have not diverged enough to make a
difference for chrony, replace Solaris in the documentation with illumos
to make it clear which system is actually supported by the chrony
project.
The dosynctodr kernel variable needs to be set to 0 to block automatic
synchronization of the system clock to the hardware clock. chronyd used
to disable dosynctodr on Solaris versions before 2.6, but it seems it is
now needed even on current versions as the clock driver sets frequency
only without calling adjtime() or setting the ntp_adjtime() PLL offset.
This issue was reproduced and fix tested on current OpenIndiana.
Fixes: 8feb37df2b ("sys_solaris: use timex driver")
In addition to the 16s limit in per-response change in the monotonic
offset, don't allow the total accumulated offset injected in sourcestats
to be larger than 16 seconds.
Check that the leap_when variable is set before testing a timestamp for
being close to a leap second. This allows the first measurement to be
accepted if starting at the Unix epoch (e.g. in a test).
Calculate the delay since the previous transmission only if the
TX timestamp is actually set. This removes an unnecessary delay when
starting at the Unix epoch in 1970 (e.g. in a test).
It seems there is no longer an issue with the first sample after the
initial trim and it can be accumulated. It might have been a workaround
for an unrelated bug which was fixed since then.
This fixes the number of samples reported in rtcdata briefly jumping to
65535 and also brings back the expectation that n_samples is never
negative.
Some of the code (e.g. util and clientlog) may work with negative
values. Require that time_t and the tv_nsec types are signed. This seems
to be the case on all supported systems, but it it is not required by
POSIX.
Close /dev/urandom and drop cached getrandom() data after forking helper
processes to avoid them getting the same sequence of random numbers
(e.g. two NTS-KE helpers generating cookies with identical nonces).
arc4random() is assumed to be able to detect forks and reseed
automatically.
This is not strictly necessary with the current code, which does not use
the GetRandom functions before the NTS-KE helper processes are forked,
but that could change in future.
Also, call the reset function before exit to close /dev/urandom in order
to avoid valgrind reporting the file object as "still reachable".
Don't ignore the magic field when searching for the exp1 extension
field in a received response. If there were two exp1 fields in the
packet, and only one of them had the expected magic value, it should
pick the right one.
Fixes: 2319f72b29 ("ntp: add client support for experimental extension field")
If the xleave option is enabled, ignore the key option and the hash
length. Always use version 4 as the default to get interleaved responses
from new chrony servers.
The interleaved modes are being specified for NTPv4 only. As a server,
detect interleaved requests only in NTPv4 packets.
Clients and peers can still send interleaved requests in lower-version
packets if configured with the version option.
Frequency transfer and time smoothing are conflicting features. Set the
monotonic timestamp in the experimental extension field to zero
(invalid) if time smoothing is activated.
The maximum value of the new 32-bit fields is slightly less than 16,
which can cause the NTP test #7 to pass for a server which has a zero
root delay but maximum root dispersion.
Interpret the maximum value as the maximum value of the original 32-bit
fields (~65536.0 seconds) for better compatibility with NTPv4.
Add "extfield F323" option to include the new extension field in
requests. If the server responds with this field, use the root
delay/dispersion and monotonic timestamp. Accumulate changes in the
offset between the monotonic and real-time receive timestamps and use
it for the correction of previous offsets in sourcestats. In the
interleaved mode, cancel out the latest change in the offset in
timestamps of the previous request and response, which were captured
before the change actually happened.
Maintain a server monotonic timescale needed for the experimental
extension field. It follows the best estimate of frequency without
time corrections. Implement it as an offset relative to the NTP time,
starting at zero, using a slew handler to cancel time corrections of the
NTP clock. The 32-bit epoch ID is set to a random value on start and
every step of the system clock.
Add an experimental extension field for some features that were proposed
for NTPv5. Higher-resolution root delay and dispersion (using 28-bit
fraction) are added. A monotonic receive timestamp will allow a
frequency transfer between the server and client. The client will be
able to separate the server's time corrections from frequency
corrections by tracking the offset between the real-time and monotonic
receive timestamps.
The field has a type of 0xF323 from the new experimental range proposed
by the NTP working group. Include a magic 32-bit value in the field to
avoid interoperability issues if a different implementation choses the
same type for its own experimental field. The value will be changed on
incompatible changes to avoid issues between two different chrony
versions.
