the 'dipsatchmgr->state' was never set, so the MGR_IS_SHUTTINGDOWN
macro was always false. both of these have been removed.
renamed the 'dispatch->state' field to 'tcpstate' to make its purpose
less ambiguous.
changed an FCTXTRACE log message from "response did not match question"
to the more correctly descriptive "invalid question section".
When a non-matching DNS response is received by the resolver,
it calls dns_dispatch_getnext() to resume reading. This is necessary
for UDP but not for TCP, because TCP connections automatically
resume reading after any valid DNS response.
This commit adds a 'tcpreading' flag to TCP dispatches, so that
`dispatch_getnext()` can be called multiple times without subsequent
calls having any effect.
the lifetime expiry timer for the fetch context was removed
when we switched to using in-band netmgr timeouts. however,
it turns out some dependency loops can occur between a fetch
and the ADB the validator; these deadlocks were formerly broken
when the timer fired, and now there's no timer. we can fix these
errors individually, but in the meantime we don't want the server
to get hung at shutdown because of dangling fetches.
this commit puts back a single timer, which fires two seconds
after the fetch should have completed, and shuts it down. it also
logs a message at level INFO so we know about the problems when
they occur.
A number of DNS implementation produce NSEC records with bad type
maps that don't contain types that exist at the name leading to
NODATA responses being synthesize instead of the records in the
zone. NSEC records with these bad type maps often have the NSEC
NSEC field set to '\000.QNAME'. We look for the first label of
this pattern.
e.g.
example.com NSEC \000.example.com SOA NS NSEC RRSIG
example.com RRRSIG NSEC ...
example.com SOA ...
example.com RRRSIG SOA ...
example.com NS ...
example.com RRRSIG NS ...
example.com A ...
example.com RRRSIG A ...
A is missing from the type map.
This introduces a temporary option 'reject-000-label' to control
this behaviour.
'server <prefix> { broken-nsec yes; };' can now be used to stop
NSEC records from negative responses from servers in the given
prefix being cached and hence available to synth-from-dnssec.
1) when after processing a node there where no headers that
contained active records.
When
if (check_stale_header(node, header, &locktype, lock, &search,
&header_prev);
succeeds or
if (EXISTS(header) && !ANCIENT(header))
fails for all entries in the list leading to 'empty_node' remaining
true.
If there is are no active records we know nothing about the
current state of the name so we treat is as ISC_R_NOTFOUND.
2) when there was a covering NOQNAME proof found or all the
active headers where negative.
When
if (header->noqname != NULL &&
header->trust == dns_trust_secure)
succeeds or
if (!NEGATIVE(header))
never succeeds. Under these conditions there could (should be for
found_noqname) be a covering NSEC earlier in the tree.
dns_nsec_noexistnodata now checks that RRSIG and NSEC are
present in the type map. Both types should be present in
a correctly constructed NSEC record. This check is in
addition to similar checks in resolver.c and validator.c.
dns_db_nodecount can now be used to get counts from the auxilary
rbt databases. The existing node count is returned by
tree=dns_dbtree_main. The nsec and nsec3 node counts by dns_dbtree_nsec
and dns_dbtree_nsec3 respectively.
"black lies" differ from "white lies" in that the owner name of the
NSEC record matches the QNAME and the intent is to return NODATA
instead of NXDOMAIN for all types. Caching this NSEC does not lead
to unexpected behaviour on synthesis when the QNAME matches the
NSEC owner which it does for the the general "white lie" response.
"black lie" QNAME NSEC \000.QNAME NSEC RRSIG
"white lie" QNAME- NSEC QNAME+ NSEC RRSIG
where QNAME- is a name that is close to QNAME but sorts before QNAME
and QNAME+ is a that is close to QNAME but sorts after QNAME.
Black lies are safe to cache as they don't bring into existence
names that are not intended to exist. "Black lies" intentional change
NXDOMAIN to NODATA. "White lies" bring QNAME- into existence and named
would synthesis NODATA for QNAME+ if it is queried for that name
instead of discovering the, presumable, NXDOMAIN response.
Note rejection NSEC RRsets with NEXT names starting with the label
'\000' renders this change ineffective (see reject-000-label).
Note when synthesising answer involving wildcards we look in the
cache multiple times, once for the QNAME and once for the wildcard
name which is constucted by looking at the names from the covering
NSEC return by the QNAME miss.
this improves the performance of looking for NSEC and RRSIG(NSEC)
records in the cache by skipping lots of nodes in the main trees
in the cache without these records present. This is a simplified
version of previous_closest_nsec() which uses the same underlying
mechanism to look for NSEC and RRSIG(NSEC) records in authorative
zones.
The auxilary NSEC tree was already being maintained as a side effect
of looking for the covering NSEC in large zones where there can be
lots of glue records that needed to be skipped. Nodes are added
to the tree whenever a NSEC record is added to the primary tree.
They are removed when the corresponding node is removed from the
primary tree.
Having nodes in the NSEC tree w/o NSEC records in the primary tree
should not impact on synth-from-dnssec efficiency as that node would
have held the NSEC we would have been needed to synthesise the
response. Removing the node when the NSEC RRset expires would only
cause rbtdb to return a NSEC which would be rejected at a higher
level.
A TCP connection may be held open past its proper timeout if it's
receiving a stream of DNS responses that don't match any queries.
In this case, we now check whether the oldest query should have timed
out.
When the outgoing TCP dispatch times-out active response, we might still
receive the answer during the lifetime of the connection. Previously,
we would just ignore any non-matching DNS answers, which would allow the
server to feed us with otherwise valid DNS answer and keep the
connection open.
Add a counter for timed-out DNS queries over TCP and tear down the whole
TCP connection if we receive unexpected number of DNS answers.
Previously, when invalid DNS message is received over TCP we throw the
garbage DNS message away and continued looking for valid DNS message
that would match our outgoing queries. This logic makes sense for UDP,
because anyone can send DNS message over UDP.
Change the logic that the TCP connection is closed when we receive
garbage, because the other side is acting malicious.
When outgoing TCP connection was prematurely terminated (f.e. with
connection reset), the dispatch code would not cleanup the resources
used by such connection leading to dangling dns_dispentry_t entries.
This commit adds support for client-side TLS parameters to XoT.
Prior to this commit all client-side TLS contexts were using default
parameters only, ignoring the options from the BIND's configuration
file.
Currently, the following 'tls' parameters are supported:
- protocols;
- ciphers;
- prefer-server-ciphers.
This commit completes the integration of the new, extended ACL syntax
featuring 'port' and 'transport' options.
The runtime presentation and ACL loading code are extended to allow
the syntax to be used beyond the 'allow-transfer' option (e.g. in
'acl' definitions and other 'allow-*' options) and can be used to
ultimately extend the ACL support with transport-only
ACLs (e.g. 'transport-acl tls-acl port 853 transport tls'). But, due
to fundamental nature of such a change, it has not been completed as a
part of 9.17.X release series due to it being close to 9.18 stable
release status. That means that we do not have enough time to fully
test it.
The complete integration is planned as a part of 9.19.X release
series.
The code was manually verified to work as expected by temporarily
enabling the extended syntax for 'acl' statements and 'allow-query'
options, including ACL merging, negated ACLs.
The parsing loop needs to process ISC_R_NOSPACE to properly
size the buffer. If result is still ISC_R_NOSPACE at the end
of the parsing loop set result to DNS_R_SERVFAIL.
In file included from rdata.c:602:
In file included from ./code.h:88:
./rdata/in_1/svcb_64.c:259:9: warning: array subscript is of type 'char' [-Wchar-subscripts]
if (!isdigit(*region->base)) {
^~~~~~~~~~~~~~~~~~~~~~
/usr/include/sys/ctype_inline.h:51:44: note: expanded from macro 'isdigit'
#define isdigit(c) ((int)((_ctype_tab_ + 1)[(c)] & _CTYPE_D))
^~~~
When a UDP dispatch receives a mismatched response, it checks whether
there is still enough time to wait for the correct one to arrive before
the timeout fires. If there is not, the result code is set to
ISC_R_TIMEDOUT, but it is not subsequently used anywhere as 'response'
is set to NULL a few lines earlier. This results in the higher-level
read callback (resquery_response() in case of resolver code) not being
called. However, shortly afterwards, a few levels up the call chain,
isc__nm_udp_read_cb() calls isc__nmsocket_timer_stop() on the dispatch
socket, effectively disabling read timeout handling for that socket.
Combined with the fact that reading is not restarted in such a case
(e.g. by calling dispatch_getnext() from udp_recv()), this leads to the
higher-level query structure remaining referenced indefinitely because
the dispatch socket it uses will neither be read from nor closed due to
a timeout. This in turn causes fetch contexts to linger around
indefinitely, which in turn i.a. prevents certain cache nodes (those
containing rdatasets used by fetch contexts, like fctx->nameservers)
from being cleaned.
Fix by making sure the higher-level callback does get invoked with the
ISC_R_TIMEDOUT result code when udp_recv() determines there is no more
time left to receive the correct UDP response before the timeout fires.
This allows the higher-level callback to clean things up, preventing the
reference leak described above.
The following scenario triggers a "named" crash:
1. Configure a catalog zone.
2. Start "named".
3. Comment out the "catalog-zone" clause.
4. Run `rndc reconfig`.
5. Uncomment the "catalog-zone" clause.
6. Run `rndc reconfig` again.
Implement the required cleanup of the in-memory catalog zone during
the first `rndc reconfig`, so that the second `rndc reconfig` could
find it in an expected state.
opensslecdsa_fromdns() already rejects too short ECDSA public keys.
Make it also reject too long ones. Remove an assignment made redundant
by this change.
raw_key_to_ossl() assumes fixed ECDSA private key sizes (32 bytes for
ECDSAP256SHA256, 48 bytes for ECDSAP384SHA384). Meanwhile, in rare
cases, ECDSAP256SHA256 private keys are representable in 31 bytes or
less (similarly for ECDSAP384SHA384) and that is how they are then
stored in the "PrivateKey" field of the key file. Nevertheless,
raw_key_to_ossl() always calls BN_bin2bn() with a fixed length argument,
which in the cases mentioned above leads to erroneously interpreting
uninitialized memory as a part of the private key. This results in the
latter being malformed and broken signatures being generated. Address
by using the key length provided by the caller rather than a fixed one.
Apply the same change to public key parsing code for consistency, adding
an INSIST() to prevent buffer overruns.
when processing a mismatched response, we call dns_dispatch_getnext().
If that fails, for example because of a timeout, fctx_done() is called,
which cancels all queries. This triggers a crash afterward when
fctx_cancelquery() is called, and is unnecessary since fctx_done()
would have been called later anyway.
When dns_adb is shutting down, first the adb->shutting_down flag is set
and then task is created that runs shutdown_stage2() that sets the
shutdown flag on names and entries. However, when dns_adb_createfind()
is called, only the individual shutdown flags are being checked, and the
global adb->shutting_down flag was not checked. Because of that it was
possible for a different thread to slip in and create new find between
the dns_adb_shutdown() and dns_adb_detach(), but before the
shutdown_stage2() task is complete. This was detected by
ThreadSanitizer as data race because the zonetable might have been
already detached by dns_view shutdown process and simultaneously
accessed by dns_adb_createfind().
This commit converts the adb->shutting_down to atomic_bool to prevent
the global adb lock when creating the find.
Add a new parameter to 'ns_client_t' to store potential extended DNS
error. Reset when the client request ends, or is put back.
Add defines for all well-known info-codes.
Update the number of DNS_EDNSOPTIONS that we are willing to set.
Create a new function to set the extended error for a client reply.
This commit makes BIND set the "max-age" value of the "Cache-Control"
HTTP header to the minimal TTL from the Answer section for positive
answers, as RFC 8484 advises in section 5.1.
We calculate the minimal TTL as a side effect of rendering the
response DNS message, so it does not change the code flow much, nor
should it have any measurable negative impact on the performance.
For negative answers, the "max-age" value is set using the TTL and
SOA-minimum values from an SOA record in the Authority section.
1) if 'key->external' is set we just need to call
dst__privstruct_writefile
2) the cleanup of 'bufs' was incorrect as 'i' doesn't reflect the
the current index into 'bufs'. Use a simple for loop.
This review was triggered by Coverity reporting a buffer overrun
on 'bufs'.
'dh' was being assigned to key->keydata.dh too soon which could
result in a memory leak on error. Moved the assignement of
key->keydata.dh until after dh was correct.
Coverity was reporting dead code on the error path cleaning up 'dh'
which triggered this review.
'make dist' omits lib/dns/tests/comparekeys/ (added in
7101afa23c) from release tarball it
creates which makes the unit:gcc:tarball CI job permanently fail in the
dst unit test.
Previously, when lame cache would be disabled by setting lame-ttl to 0,
it would also disable lame answer detection. In this commit, we enable
the lame response detection even when the lame cache is disabled. This
enables stopping answer processing early rather than going through the
whole answer processing flow.
OpenSSL 3 deprecates most of the DH* family and associated APIs.
Reimplement the existing functionality using a newer set of APIs
which will be used when compiling/linking with OpenSSL 3.0.0 or newer
versions.
OpenSSL 3 deprecates most of the RSA* family and associated APIs.
Reimplement the existing functionality using a newer set of APIs
which will be used when compiling/linking with OpenSSL 3.0.0 or newer
versions.
OpenSSL 3 deprecates most of the EC* family and associated APIs.
Reimplement the existing functionality using a newer set of APIs
which will be used when compiling/linking with OpenSSL 3.0.0 or newer
versions.
EVP_PKEY_eq() is the replacement with a smaller result range (0, 1)
instead of (-1, 0, 1). EVP_PKEY_cmp() is mapped to EVP_PKEY_eq() when
building with older versions of OpenSSL.
OpenSSL 3.0.0 deprecates the ERR_get_error_line_data() function.
Use ERR_get_error_all() instead of ERR_get_error_line_data() and create
a shim to use the old variant for the older OpenSSL versions which don't
have the newer ERR_get_error_all().
