Trying to resolve a trust anchor telemetry query for a locally served
zone does not cause upstream queries to be sent as the response is
determined just by consulting local data. Work around this issue by
calling dns_view_findzonecut() first in order to determine the NS RRset
for a given domain name and then passing the zone cut found to
dns_resolver_createfetch().
Note that this change only applies to TAT queries generated by the
resolver itself, not to ones received from downstream resolvers.
Extract the part of dotat() reponsible for preparing the QNAME for a TAT
query to a separate function in order to limit the number of local
variables used by each function and improve code readability.
Rename 'name' to 'origin' to better convey the purpose of that variable.
Also mark it with the const qualifier.
Update named_zone_reusable() so that it does not consider a zone to be
eligible for reuse if its old value of the "mirror" option differs from
the new one. This causes "rndc reconfig" to create a new zone structure
whenever the value of the "mirror" option is changed, which ensures that
the previous zone database is not reused and that flags are properly set
in responses sourced from zones whose "mirror" setting was changed at
runtime.
Replace "type: slave" with "type: mirror" in "rndc zonestatus" output
for mirror zones in order to enable the user to tell a regular slave
zone and a mirror zone apart.
Since the mirror zone feature is expected to mostly be used for the root
zone, prevent slaves from sending NOTIFY messages for mirror zones by
default. Retain the possibility to use "also-notify" as it might be
useful in certain cases.
As mirror zone data should be treated the way validated, cached DNS
responses are, outgoing mirror zone transfers should be disabled unless
they are explicitly enabled by zone configuration.
Add a new slave-only boolean configuration option, "mirror", along with
its corresponding dns_zoneopt_t enum and a helper function for checking
whether that option was set for a given zone. This commit does not
introduce any behavior changes yet.
- make qname-minimization option tristate {strict,relaxed,disabled}
- go straight for the record if we hit NXDOMAIN in relaxed mode
- go straight for the record after 3 labels without new delegation or 7 labels total
- use start of fetch (and not time of response) as 'now' time for querying cache for
zonecut when following delegation.
- the default setting for dnssec-validation is now "auto", which
activates DNSSEC validation using the IANA root key. The old behavior
can be restored by explicitly setting "dnssec-validation yes", which
"yes", which activates DNSSEC validation only if keys are explicitly
configured in named.conf.
- the ARM has been updated to describe the new behavior
This commit reverts the previous change to use system provided
entropy, as (SYS_)getrandom is very slow on Linux because it is
a syscall.
The change introduced in this commit adds a new call isc_nonce_buf
that uses CSPRNG from cryptographic library provider to generate
secure data that can be and must be used for generating nonces.
Example usage would be DNS cookies.
The isc_random() API has been changed to use fast PRNG that is not
cryptographically secure, but runs entirely in user space. Two
contestants have been considered xoroshiro family of the functions
by Villa&Blackman and PCG by O'Neill. After a consideration the
xoshiro128starstar function has been used as uint32_t random number
provider because it is very fast and has good enough properties
for our usage pattern.
The other change introduced in the commit is the more extensive usage
of isc_random_uniform in places where the usage pattern was
isc_random() % n to prevent modulo bias. For usage patterns where
only 16 or 8 bits are needed (DNS Message ID), the isc_random()
functions has been renamed to isc_random32(), and isc_random16() and
isc_random8() functions have been introduced by &-ing the
isc_random32() output with 0xffff and 0xff. Please note that the
functions that uses stripped down bit count doesn't pass our
NIST SP 800-22 based random test.
- added a 1-second floor to max-stale-ttl similar to stale-answer-ttl;
if set to 0, it will be silently updated to 1.
- fixed the ARM entry on max-stale-ttl, which incorrectly suggested that
the default was 0 instead of 1 week.
- clarified rndc serve-stale documentation.
- mark the 'geoip-use-ecs' option obsolete; warn when it is used
in named.conf
- prohibit 'ecs' ACL tags in named.conf; note that this is a fatal error
since simply ignoring the tags could make ACLs behave unpredictably
- re-simplify the radix and iptable code
- clean up dns_acl_match(), dns_aclelement_match(), dns_acl_allowed()
and dns_geoip_match() so they no longer take ecs options
- remove the ECS-specific unit and system test cases
- remove references to ECS from the ARM
- Replace external -DOPENSSL/-DPKCS11CRYPTO with properly AC_DEFINEd
HAVE_OPENSSL/HAVE_PKCS11
- Don't enforce the crypto provider from platform.h, just from dst_api.c
and configure scripts
The three functions has been modeled after the arc4random family of
functions, and they will always return random bytes.
The isc_random family of functions internally use these CSPRNG (if available):
1. getrandom() libc call (might be available on Linux and Solaris)
2. SYS_getrandom syscall (might be available on Linux, detected at runtime)
3. arc4random(), arc4random_buf() and arc4random_uniform() (available on BSDs and Mac OS X)
4. crypto library function:
4a. RAND_bytes in case OpenSSL
4b. pkcs_C_GenerateRandom() in case PKCS#11 library
Replace dns_fixedname_init() calls followed by dns_fixedname_name()
calls with calls to dns_fixedname_initname() where it is possible
without affecting current behavior and/or performance.
This patch was mostly prepared using Coccinelle and the following
semantic patch:
@@
expression fixedname, name;
@@
- dns_fixedname_init(&fixedname);
...
- name = dns_fixedname_name(&fixedname);
+ name = dns_fixedname_initname(&fixedname);
The resulting set of changes was then manually reviewed to exclude false
positives and apply minor tweaks.
It is likely that more occurrences of this pattern can be refactored in
an identical way. This commit only takes care of the low-hanging fruit.
