In selfsigned_dnskey only call dns_dnssec_verify if the signature's
key id matches a revoked key, the trust is pending and the key
matches a trust anchor. Previously named was calling dns_dnssec_verify
unconditionally resulted in busy work.
The 'nsupdate' tool, when sending SOA queries, uses a hard-coded value
3 UDP retries and of 5 seconds of timeout for UDP queries, and 100
seconds of timeout for TCP queries.
Use the timeout and retry values which can be configured using the
-t, -u, -r command line options, and which are already used for
sending the update query.
The req_response() function is using 'udpcount' variable to resend
the request 'udpcount' times on timeout even for TCP requests,
which does not make sense, as it would use the same connection.
Add a condition to use the resend logic only for UDP requests.
The dns_request_createraw() function, unlike dns_request_create(), when
calculating the UDP timeout value, doesn't check that 'udpretries' is
not zero, and that is the more logical behavior, because the calculation
formula uses division to 'udpretries + 1', where '1' is the first try.
Change the dns_request_create() function to remove the 'udpretries != 0'
condition.
Add a 'REQUIRE(udpretries != UINT_MAX)' check to protect from a division
by zero.
Make the 'request->udpcount' field to represent the number of tries,
instead of the number of retries.
The manual page of nsupdate's '-u udptimeout' option states that, quote:
> If zero, the interval is computed from the timeout interval and number
> of UDP retries.
However, nsupdate sets the UDP timeout value to UINT_MAX when it is 0,
thus, not behaving as documented.
Let dns_request_create() calculate the UDP timeout, if it was set to 0.
* nsupdate should take 12 seconds (one try and three retries with
3 second timeout for each), UDP mode
* nsupdate -u 4 -r 1 should take 8 seconds (one try and one retry with
4 second timeout for each), UDP mode
* nsupdate -u 0 -t 8 -r 1 should also take 8 seconds, UDP mode
* nsupdate -u 4 -t 30 -r 1 should also take 8 seconds, as -u takes
precedence over -t, UDP mode
* nsupdate -t 8 -v should also take 8 seconds, TCP mode
My original idea had been that the core qp-trie code would be mostly
independent of the storage for keys, so I did not make it check at run
time that key lengths are sensible. However, the qp-trie search
routines need to get keys out of leaf objects, for which they provide
storage on the stack, which is particularly dangerous for unchecked
buffer overflows. So this change checks that key lengths are in bounds
at the API boundary between the qp-trie code and the rest of BIND, and
there is no more pretence that keys might be longer.
The checkds system test could fail if some parent secondary servers did
not yet loaded all the zones before ns9 started sending DS queries. This
leads to SERVFAIL responses, while the test case expects good DS
responses. In order to mitigate against this issue, call 'rndc loadkeys'
to quickly restart the checkds procedure again.
Also refactor the checkds system test, to get rid of the many zone
name duplications. Update the functions 'zone_check' and
'keystate_check' to make the zone name an FQDN so we can just pass
the 'zone' variable into the function.
If the 'checkds' option is not explicitly set, check if there are
'parental-agents' for the zone configured. If so, default to "explicit",
otherwise default to "yes".
Add two new checkds test servers, that are hidden secondaries (hidden
as in not published in the NS RRset), that can be used specifically
for testing explicitly configured parental-agents.
Implement the new feature, automatic parental-agents. This is enabled
with 'checkds yes'.
When set to 'yes', instead of querying the explicit configured
parental agents, look up the parental agents by resolving the parent
NS records. The found parent NS RRset is considered to be the list
of parental agents that should be queried during a KSK rollover,
looking up the DS RRset corresponding to the key signing keys.
For each NS record, look up the addresses in the ADB. These addresses
will be used to send the DS requests. Count the number of servers and
keep track of how many good DS responses were seen.
The previous test cases already test the more complex case where there
are empty non-terminals between the child apex and the parent domain.
Add a test case where this is not the case, to execute the other code
path.
Add test cases for when checkds is disabled. Copy the test cases that
would have resulted in a DSPublish or DSRemoved and make sure that
with 'checkds no' the metadata is not set.
Add the test cases for automatic parental-agents, i.e. when 'checkds'
is set to 'yes'. Split out the special cases that use a reference
or a resolver as parental-agent so that the common use cases can be
tested with the same function.
Make the checkds system test more structured with the many more test
cases to come. Add a README for clarity.
Update the 'has_signed_apex_nsec' helper function so it can take any
domain name regardless of the number of labels.
Change the DNS tree structure such that we have different TLD names
for the various test scenarios, because we need servers that respond
differently to DS queries. Note that this isn't applicable to the
existing "checkds explicit" test cases, but is preparation work for
testing "checkds yes" (automatic parental agents).
Add a trust-anchor to the server that will be querying for parent
NS records.
Add a new configuration option to set how the checkds method should
work. Acceptable values are 'yes', 'no', and 'explicit'.
When set to 'yes', the checkds method is to lookup the parental agents
by querying the NS records of the parent zone.
When set to 'no', no checkds method is enabled. Users should run
the 'rndc checkds' command to signal that DS records are published and
withdrawn.
When set to 'explicit', the parental agents are explicitly configured
with the 'parental-agents' configuration option.
Only attempt to digest 'in' if it is non NULL. This will prevent
false positives about NULL pointer dereferences against 'in' and
should also speed up the processing.
This commit optimises isc_dnsstream_assembler_t in such a way that
memory copying and reallocation are avoided when receiving one or more
complete DNS messages at once. We try to handle the data from the
messages directly, without storing them in an intermediate memory
buffer.
In write_public_key() and write_key_state(), there were left-over checks
for result, that were effectively dead code after the last refactoring.
Remove those.
This should have no functional effects.
The message size stats are specified by RSSAC002 so it's best not
to mess around with how they appear in the statschannel. But it's
worth changing the implementation to use general-purpose histograms,
to reduce code size and benefit from sharded counters.
The `isc_histosummary_t` functions were written in the early days of
`hg64` and carried over when I brought `hg64` into BIND. They were
intended to be useful for graphing cumulative frequency distributions
and the like, but in practice whatever draws charts is better off with
a raw histogram export. Especially because of the poor performance of
the old functions.
The replacement `isc_histo_quantiles()` function is intended for
providing a few quantile values in BIND's stats channel, when the user
does not want the full histogram. Unlike the old functions, the caller
provides all the query fractions up-front, so that the values can be
found in a single scan instead of a scan per value. The scan is from
larger values to smaller, since larger quantiles are usually more
interesting, so the scan can bail out early.
Although an `isc_histo_t` is thread-safe, it can suffer
from cache contention under heavy load. To avoid this,
an `isc_histomulti_t` contains a histogram per thread,
so updates are local and low-contention.
This is an adaptation of my `hg64` experiments for use in BIND.
As well as renaming everything according to ISC style, I have
written some more extensive tests that ensure the edge cases are
correct and the fenceposts are in the right places.
I have added utility functions for working with precision in terms of
decimal significant figures as well as this code's native binary.
