The directive sets the DSCP value in transmitted NTP packets, which can
be useful in local networks where switches/routers are configured to
prioritise packets with specific DSCP values.
Before generating a MAC, make sure there is enough space in the packet.
This is always true with the current code, but it may change when a
non-NTS extension field is supported.
Update the packet auth info after generating a MAC in case it's needed
before the transmission.
Add more assertions and make other changes for better readability.
It seems gnutls (at least in version 3.6.14) allows clients to connect
using TLS1.2 when it has a DTLS version enabled in the priority cache.
Disable all DTLS versions in order to disable TLS1.2.
Destroy the NTS-KE session of the client immediately even when the
resolver of the NTP address is running. This removes the session
local change handler and avoids an assertion failure in the local
finalization.
When the request has an unrecognized critical record before the
NEXT_PROTOCOL and AEAD_ALGORITHM records, respond with error 0
(unrecognized critical record) instead of 1 (bad request).
When the request has multiple NEXT_PROTOCOL or AEAD_ALGORITHM records,
respond with error 1 (bad request).
Add a function to get the current minimum severity and a function to set
a global prefix for debug messages in order to identify messages from
helpers.
For consistency and safety, change the CMC and HSH functions to accept
signed lengths and handle negative values as errors. Also, change the
input data type to void * to not require casting in the caller.
Modify NNA_DecryptAuthEF() to not assume that the authenticator is the
last extension field in the packet as some extension fields specified in
future may need to be placed after the authenticator. The caller of the
function is supposed to verify the position.
Add more comments and assertions, replace getsockopt() call with
SCK_GetIntOption(), replace strncmp() with memcmp(), move a return
statement for clarity, and remove an unused field from the instance
record.
The daemon transmit timestamps are precompensated for the time it takes
to generate a MAC using a symmetric key (as measured on chronyd start)
and also an average round-trip time of the Samba signing of MS-SNTP
responses. This improves accuracy of the transmit timestamp, but it
has some issues.
The correction has a random error which is changing over time due to
variable CPU frequency, system load, migration to a different machine,
etc. If the measured delay is too large, the correction may cause the
transmit timestamp to be later than the actual transmission. Also, the
delay is measured for a packet of a minimal length with no extension
fields, and there is no support for NTS.
Drop the precompensation in favor of the interleaved mode, which now
avoids the authentication delay even when no kernel/hardware timestamps
are available.
If the daemon transmit timestamp is saved for processing of a future
response or responding in the interleaved mode, get a more accurate
timestamp right before calling NIO_SendPacket(). Avoid unnecessary
reading of the clock for the transmit timestamp in the packet (i.e.
in interleaved modes and client basic mode).
This should improve accuracy and stability when authentication is
enabled in the client and symmetric basic modes and also interleaved
modes if kernel/hardware timestamps are not available.
After commit e49aececce ("socket: don't set interface for sent
packets") the NTP and cmdmon server stopped responding to requests from
link-local addresses.
Set the interface specifically for packets sent to a link-local address.
