Commit graph

13953 commits

Author SHA1 Message Date
Mark Andrews
3d223e0338
Replace alg_totext with dst_hmac_algorithm_totext
The new library function will be reused by subsequent commits.

(cherry picked from commit 151cc2fff9)
2022-09-27 16:55:33 +02:00
Mark Andrews
0bbc0c61e3
Convert DST_ALG defines to enum and group HMAC algorithms
The HMACs and GSSAPI are just using unallocated values.
Moving them around shouldn't cause issues.
Only the dnssec system test knew the internal number in use for hmacmd5.

(cherry picked from commit 09f7e0607a)
2022-09-27 16:55:33 +02:00
Mark Andrews
83726e2fd3 Check that primary key names have not changed
When looking for changes in a catalog zone member zone we need to
also check if the TSIG key name associated with a primary server
has be added, removed or changed.

(cherry picked from commit 9172bd9b5a)
2022-09-27 22:19:37 +10:00
Evan Hunt
369858730a change ISC__BUFFER macros to inline functions
previously, when ISC_BUFFER_USEINLINE was defined, macros were
used to implement isc_buffer primitives (isc_buffer_init(),
isc_buffer_region(), etc). these macros were missing the DbC
assertions for those primitives, which made it possible for
coding errors to go undetected.

adding the assertions to the macros caused compiler warnings on
some platforms. therefore, this commit converts the ISC__BUFFER
macros to static inline functions instead, with assertions included,
and eliminates the non-inline implementation from buffer.c.

the --enable-buffer-useinline configure option has been removed.

(cherry picked from commit 1926ddc987)
2022-09-27 00:45:28 -07:00
Ondřej Surý
c66c687bd6
Add the ability specify the signing / verification time
When fuzzing it is useful for all signing operations to happen
at a specific time for reproducability.  Add two variables to
the message structure (fuzzing and fuzztime) to specify if a
fixed time should be used and the value of that time.

(cherry picked from commit 3e85d8c3d6)
2022-09-26 16:30:36 +02:00
Mark Andrews
1488ef19f8
Stop passing mctx to dns_rdata_tostruct as it is unnecessary for SIG
dns_rdata_tostruct doesn't need a mctx passed to it for SIG (the signer
is already expanded at this point). About the only time when mctx is
needed is when the structure is to be used after the rdata has been
destroyed.

(cherry picked from commit d6ad56bd9e)
2022-09-26 12:01:44 +02:00
Petr Špaček
9a971bb8b0
Fix memory leak in dns_message_checksig() - SIG(0) sigs
Impact should be visible only in tests or tools because named never
uses view == NULL, which is a necessary condition to trigger this leak.

(cherry picked from commit 69256b3553)
2022-09-26 12:01:40 +02:00
Petr Menšík
8a425dbac4 Remove engine related parts for OpenSSL 3.0
OpenSSL just cannot work with mixing ENGINE_* api mixed with OSSL_PARAM
builders. But it can be built in legacy mode, where deprecated but still
working API would be used.

It can work under OpenSSL 3.0, but only if using legacy code paths
matching OpenSSL 1.1 calls and functions.

Remove fromlabel processing by OpenSSL 3.0 only functions. They can
return later with a proper provider support for pkcs11.

(cherry picked from commit 6c55ea17c6)
2022-09-23 14:07:21 +10:00
Petr Menšík
d6806c9fe7 Do not use OSSL_PARAM when engine API is compiled
OpenSSL has deprecated many things in version 3.0. If pkcs11 engine
should work then no builder from OpenSSL 3.0 API can be used.

Allow switching to OpenSSL 1.1 like calls even on OpenSSL 3.0 when
OPENSSL_API_COMPAT=10100 is defined. It would still compile and allow
working keys loading from the engine passed on command line.

(cherry picked from commit f92950bb64)
2022-09-23 14:07:14 +10:00
Petr Menšík
306f1008cc Add ENGINE_init and ENGINE_finish calls
According to manual page of ENGINE_init, it should be called explicitly
before any key operations happens. Make it active whole lifetime.

(cherry picked from commit 71a8f1e7cd)
2022-09-23 14:05:16 +10:00
Evan Hunt
357b59ec68 additional code cleanups in httpd.c
- use isc_buffer functions when appropriate, rather than converting
  to and from isc_region unnecessarily
- use the zlib total_out value instead of calculating it
- use c99 struct initialization

(cherry picked from commit 4b7248545e)
2022-09-21 12:54:27 -07:00
Michał Kępień
0a53f61727 BIND 9.18.7
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Merge tag 'v9_18_7' into v9_18

BIND 9.18.7
2022-09-21 13:13:30 +02:00
Evan Hunt
8f61d07918 merge dns_request_createvia() into dns_request_create()
dns_request_create() was a front-end to dns_request_createvia() that
was only used by test binaries. dns_request_createvia() has been
renamed to dns_request_create(), and the test programs that formerly
used dns_request_create() have been updated to use the new parameters.

(cherry picked from commit ebf7b31aa3)
2022-09-15 16:49:04 -07:00
Evan Hunt
592c7b1049 fix an incorrect detach in update processing
when processing UDPATE requests, hold the request handle until
we either drop the request or respond to it.

(cherry picked from commit 00e0758e12)
2022-09-15 11:34:33 -07:00
Ondřej Surý
2adaa53619
Handle canceled read during sending data over stats channel
An assertion failure would be triggered when the TCP connection
is canceled during sending the data back to the client.

Don't require the state to be `RECV` on non successful read to
gracefully handle canceled TCP connection during the SEND state of the
HTTPD channel.

(cherry picked from commit 6562227cc8)
2022-09-15 10:58:09 +02:00
Petr Špaček
c095ac9ad1
Log reason why cache peek is not available
Log which ACL caused RD=0 query into cache to be refused.
Expected performance impact is negligible.

(cherry picked from commit fdf7456643)
2022-09-15 09:41:01 +02:00
Petr Špaček
e067d11396
Log reason why recursion is not available
Log which ACL caused RA=0 condition.
Expected performance impact is negligible.

(cherry picked from commit 95fc05c454)
2022-09-15 09:40:57 +02:00
Evan Hunt
17da7dee5c flag "random-device" as obsolete
the "random-device" option was made non-functional in 9.13, but was
not marked as obsolete at that time. this is now fixed; configuring
"random-device" will trigger a warning.
2022-09-14 09:37:25 -07:00
Mark Andrews
7c0028cfad Free ctx on invalid siglen
(cherry picked from commit 6ddb480a84)
2022-09-08 11:55:29 +02:00
Matthijs Mekking
b9e2f3333d Only refresh RRset once
Don't attempt to resolve DNS responses for intermediate results. This
may create multiple refreshes and can cause a crash.

One scenario is where for the query there is a CNAME and canonical
answer in cache that are both stale. This will trigger a refresh of
the RRsets because we encountered stale data and we prioritized it over
the lookup. It will trigger a refresh of both RRsets. When we start
recursing, it will detect a recursion loop because the recursion
parameters will eventually be the same. In 'dns_resolver_destroyfetch'
the sanity check fails, one of the callers did not get its event back
before trying to destroy the fetch.

Move the call to 'query_refresh_rrset' to 'ns_query_done', so that it
is only called once per client request.

Another scenario is where for the query there is a stale CNAME in the
cache that points to a record that is also in cache but not stale. This
will trigger a refresh of the RRset (because we encountered stale data
and we prioritized it over the lookup).

We mark RRsets that we add to the message with
DNS_RDATASETATTR_STALE_ADDED to prevent adding a duplicate RRset when
a stale lookup and a normal lookup conflict with each other. However,
the other non-stale RRset when following a CNAME chain will be added to
the message without setting that attribute, because it is not stale.

This is a variant of the bug in #2594. The fix covered the same crash
but for stale-answer-client-timeout > 0.

Fix this by clearing all RRsets from the message before refreshing.
This requires the refresh to happen after the query is send back to
the client.

(cherry picked from commit d939d2ecde)
2022-09-08 11:50:44 +02:00
Aram Sargsyan
73df5c8053 Fix memory leaks in DH code
When used with OpenSSL v3.0.0+, the `openssldh_compare()`,
`openssldh_paramcompare()`, and `openssldh_todns()` functions
fail to cleanup the used memory on some error paths.

Use `DST_RET` instead of `return`, when there is memory to be
released before returning from the functions.

(cherry picked from commit 73d6bbff4e)
2022-09-08 11:46:20 +02:00
Evan Hunt
13333db69f compression buffer was not reused correctly
when the compression buffer was reused for multiple statistics
requests, responses could grow beyond the correct size. this was
because the buffer was not cleared before reuse; compressed data
was still written to the beginning of the buffer, but then the size
of used region was increased by the amount written, rather than set
to the amount written. this caused responses to grow larger and
larger, potentially reading past the end of the allocated buffer.

(cherry picked from commit 47e9fa981e)
2022-09-08 11:40:18 +02:00
Michał Kępień
e2014ba9e3 Bound the amount of work performed for delegations
Limit the amount of database lookups that can be triggered in
fctx_getaddresses() (i.e. when determining the name server addresses to
query next) by setting a hard limit on the number of NS RRs processed
for any delegation encountered.  Without any limit in place, named can
be forced to perform large amounts of database lookups per each query
received, which severely impacts resolver performance.

The limit used (20) is an arbitrary value that is considered to be big
enough for any sane DNS delegation.

(cherry picked from commit 3a44097fd6)
2022-09-08 11:11:30 +02:00
Aram Sargsyan
35e37505f0 Fix RRL responses-per-second bypass using wildcard names
It is possible to bypass Response Rate Limiting (RRL)
`responses-per-second` limitation using specially crafted wildcard
names, because the current implementation, when encountering a found
DNS name generated from a wildcard record, just strips the leftmost
label of the name before making a key for the bucket.

While that technique helps with limiting random requests like
<random>.example.com (because all those requests will be accounted
as belonging to a bucket constructed from "example.com" name), it does
not help with random names like subdomain.<random>.example.com.

The best solution would have been to strip not just the leftmost
label, but as many labels as necessary until reaching the suffix part
of the wildcard record from which the found name is generated, however,
we do not have that information readily available in the context of RRL
processing code.

Fix the issue by interpreting all valid wildcard domain names as
the zone's origin name concatenated to the "*" name, so they all will
be put into the same bucket.

(cherry picked from commit baa9698c9d)
2022-09-08 09:36:50 +02:00
Evan Hunt
acfca3f4fa when creating an interface, set magic before linking
set the magic number in a newly-created interface object
before appending it to mgr->interfaces in order to prevent
a possible assertion.

(cherry picked from commit 8c01662048)
2022-09-06 21:48:28 -07:00
Matthijs Mekking
d7175c41a7 dnssec-policy now requires inline-signing
Having implicit inline-signing set for dnssec-policy when there is no
update policy is confusing, so lets make this explicit.

(cherry picked from commit 5ca02fe6e7e591d1fb85936ea4dda720c3d741ef)
2022-09-06 09:02:59 +02:00
Aram Sargsyan
982b491d7c Add mctx attach/detach when creating/destroying a memory pool
This should make sure that the memory context is not destroyed
before the memory pool, which is using the context.

(cherry picked from commit e97c3eea95)
2022-09-02 08:17:47 +00:00
Evan Hunt
7bb503ca75 dnstap query_message field was erroneously set with responses
The dnstap query_message field was in some cases being filled in
with response messages, along with the response_message field.
The query_message field should only be used when logging requests,
and the response_message field only when logging responses.

(cherry picked from commit 3ccfff8ab6)
2022-08-31 15:24:00 -07:00
Matthijs Mekking
e54ab3f586 nsec3.c: Add a missing dns_db_detachnode() call
There is one case in 'dns_nsec3_activex()' where it returns but forgets
to detach the db node. Add the missing 'dns_db_detachnode()' call.

This case only triggers if 'sig-signing-type' (privatetype) is set to 0
(which by default is not), or if the function is called with 'complete'
is set to 'true' (which at this moment do not exist).

(cherry picked from commit 0cf6c18ccb2205a1fc81431f908c8310f6136bbb)
2022-08-23 12:04:08 +02:00
Matthijs Mekking
39c0c5022d Wait with NSEC3 during a DNSSEC policy change
When doing a dnssec-policy reconfiguration from a zone with NSEC only
keys to a zone that uses NSEC3, figure out to wait with building the
NSEC3 chain.

Previously, BIND 9 would attempt to sign such a zone, but failed to
do so because the NSEC3 chain conflicted with existing DNSKEY records
in the zone that were not compatible with NSEC3.

There exists logic for detecting such a case in the functions
dnskey_sane() (in lib/dns/zone.c) and check_dnssec() (in
lib/ns/update.c). Both functions look very similar so refactor them
to use the same code and call the new function (called
dns_zone_check_dnskey_nsec3()).

Also update the dns_nsec_nseconly() function to take an additional
parameter 'diff' that, if provided, will be checked whether an
offending NSEC only DNSKEY will be deleted from the zone. If so,
this key will not be considered when checking the zone for NSEC only
DNSKEYs. This is needed to allow a transition from an NSEC zone with
NSEC only DNSKEYs to an NSEC3 zone.

(cherry picked from commit 09a81dc84ce0fee37442f03cdbd63c2398215376)
2022-08-22 19:21:39 +02:00
Aram Sargsyan
d4c5d1c650 Fix statistics channel multiple request processing with non-empty bodies
When the HTTP request has a body part after the HTTP headers, it is
not getting processed and is being prepended to the next request's data,
which results in an error when trying to parse it.

Improve the httpd.c:process_request() function with the following
additions:

1. Require that HTTP POST requests must have Content-Length header.
2. When Content-Length header is set, extract its value, and make sure
   that it is valid and that the whole request's body is received before
   processing the request.
3. Discard the request's body by consuming Content-Length worth of data
   in the buffer.

(cherry picked from commit c2bbdc8a648c9630b2c9cea5227ad5c309c2ade5)
2022-08-19 08:27:01 +00:00
Aram Sargsyan
1005dd74d9 Enhance the have_header() function to find the HTTP header's value
Add a new `const char **fvalue` parameter to the httpd.c:have_header()
function which, when set, will point to the found header's value.

(cherry picked from commit 376e698dc21f4117d6461101c4cfbaef2b724592)
2022-08-19 08:26:18 +00:00
Mark Andrews
f7590c1c5a Silence negative array index warning with toupper
Cast to (unsigned char).

(cherry picked from commit d3f790340e8590ad5da1472c99d25acbc9818496)
2022-08-19 12:31:04 +10:00
Aram Sargsyan
b46e53a2e3 Fix tkey.c:buildquery() function's error handling
Add the missing cleanup code.

(cherry picked from commit 4237ab9550eeaea7121e3e3392fd14c26b5150f0)
2022-08-17 08:36:07 +00:00
Evan Hunt
f841f545b7 Lock the address entry bucket when dumping ADB namehook
When dumping an ADB address entry associated with a name,
the name bucket lock was held, but the entry bucket lock was
not; this could cause data races when other threads were updating
address entry info. (These races are probably not operationally
harmful, but they triggered TSAN error reports.)
2022-08-12 15:55:41 -07:00
Evan Hunt
1843780151 fix overflow error in mem_putstats()
an integer overflow could cause an assertion failure when
freeing memory.

(cherry picked from commit 0401e0867b1516386fab9b390b750a2f99883188)
2022-08-09 11:21:35 -07:00
Matthijs Mekking
5e908a988f Don't enable serve-stale on duplicate queries
When checking if we should enable serve-stale, add an early out case
when the result is an error signalling a duplicate query or a query
that would be dropped.

(cherry picked from commit 059a4c2f4d9d3cff371842f43208d021509314fa)
2022-08-09 09:36:11 +02:00
Artem Boldariev
c2fa72027c TLS: do not ignore readpaused flag in certain circumstances
In some circumstances generic TLS code could have resumed data reading
unexpectedly on the TCP layer code. Due to this, the behaviour of
isc_nm_pauseread() and isc_nm_resumeread() might have been
unexpected. This commit fixes that.

The bug does not seems to have real consequences in the existing code
due to the way the code is used. However, the bug could have lead to
unexpected behaviour and, at any rate, makes the TLS code behave
differently from the TCP code, with which it attempts to be as
compatible as possible.

(cherry picked from commit ec0647d546204a0e09aeaf0e2aabb37f1fb67dd0)
2022-08-02 17:31:15 +03:00
Aram Sargsyan
47e4ef0696 Improve fetch limit logging
When initially hitting the `fetches-per-zone` value, a log message
is being generated for the event of dropping the first fetch, then
any further log events occur only when another fetch is being dropped
and 60 seconds have been passed since the last logged message.

That logic isn't ideal because when the counter of the outstanding
fetches reaches zero, the structure holding the counters' values will
get deleted, and the information about the dropped fetches accumulated
during the last minute will not be logged.

Improve the fcount_logspill() function to makie sure that the final
values are getting logged before the counter object gets destroyed.

(cherry picked from commit 039871ceb767088205563965f7aae622a3f77082)
2022-08-01 13:54:46 +00:00
Artem Boldariev
a957511734 TLS: fix double resumption in isc__nm_tls_resumeread()
This commit fixes an obvious error in isc__nm_tls_resumeread() so that
read cannot be resumed twice.
2022-07-26 15:27:40 +03:00
Artem Boldariev
a165b66fc7 TLS: clear 'errno' when handling SSL status
Sometimes tls_do_bio() might be called when there is no new data to
process (most notably, when resuming reads), in such a case internal
TLS session state will remain untouched and old value in 'errno' will
alter the result of SSL_get_error() call, possibly making it to return
SSL_ERROR_SYSCALL. This value will be treated as an error, and will
lead to closing the connection, which is not what expected.
2022-07-26 15:27:40 +03:00
Mark Andrews
f3a0dac057 Check that we can verify a signature at initialisation time
Fedora 33 doesn't support RSASHA1 in future mode.  There is no easy
check for this other than by attempting to perform a verification
using known good signatures.  We don't attempt to sign with RSASHA1
as that would not work in FIPS mode.  RSASHA1 is verify only.

The test vectors were generated using OpenSSL 3.0 and
util/gen-rsa-sha-vectors.c.  Rerunning will generate a new set of
test vectors as the private key is not preserved.

e.g.
	cc util/gen-rsa-sha-vectors.c -I /opt/local/include \
		-L /opt/local/lib -lcrypto

(cherry picked from commit cd3f00874f63a50954cebb78edac8f580a27c0de)
2022-07-25 10:59:38 -04:00
Matthijs Mekking
56f1bf250d Fix rndc dumpdb -expired for stuck cache contents
The command 'rndc dumpdb -expired' will include expired RRsets in the
output, but only for the RBTDB_VIRTUAL time (of 5 minutes). This means
that if there is a cache cleaning problem and contents are not cleaned
up, the rndc command has little diagnostic value. Fix this by including
all RRsets in the dumpdb output if the '-expired' flag is set.

(cherry picked from commit 930ba2c914a0abc07fd087d663a7bfb57850d4ca)
2022-07-25 16:28:18 +02:00
Evan Hunt
4720f13730 warn about zones with both dnssec-policy and max-zone-ttl
max-zone-ttl in zone/view/options is a no-op if dnssec-policy
is in use, so generate a warning.
2022-07-22 13:13:24 -07:00
Ondřej Surý
3c1d6e164e
Increase the BUFSIZ-long buffers
The BUFSIZ value varies between platforms, it could be 8K on Linux and
512 bytes on mingw.  Make sure the buffers are always big enough for the
output data to prevent truncation of the output by appropriately
enlarging or sizing the buffers.

(cherry picked from commit b19d932262e84608174cb89eeed32ae0212f8a87)
2022-07-15 21:16:51 +02:00
Evan Hunt
7903bffbc4 remove unnecessary assertion in dns_dispatch_connect()
When a thread calls dns_dispatch_connect() on an unconnected TCP socket
it sets `tcpstate` from `DNS_DISPATCHSTATE_NONE` to `_CONNECTING`.
Previously, it then INSISTed that there were no pending connections
before calling isc_nm_tcpdnsconnect().

If a second thread called dns_dispatch_connect() during that window
of time, it could add a pending connection to the list, and trigger
an assertion failure.

This commit removes the INSIST since the condition is actually
harmless.

(cherry picked from commit 25ddec8a0a8e0549b69f4e601028f3323d3c1886)
2022-07-14 19:27:24 -07:00
Ondřej Surý
d242ced18f
Cleanup the STATID_CONNECT and STATID_CONNECTFAIL stat counters
The STATID_CONNECT and STATID_CONNECTFAIL statistics were used
incorrectly. The STATID_CONNECT was incremented twice (once in
the *_connect_direct() and once in the callback) and STATID_CONNECTFAIL
would not be incremented at all if the failure happened in the callback.

Closes: #3452
(cherry picked from commit 59e1703b50dc4a5c52e3d6ae13bdd873a677b03f)
2022-07-14 21:48:44 +02:00
Ondřej Surý
259f4481bd
Handle the transient TCP connect() failures on FreeBSD
On FreeBSD (and perhaps other *BSD) systems, the TCP connect() call (via
uv_tcp_connect()) can fail with transient UV_EADDRINUSE error.  The UDP
code already handles this by trying three times (is a charm) before
giving up.  Add a code for the TCP, TCPDNS and TLSDNS layers to also try
three times before giving up by calling uv_tcp_connect() from the
callback two more time on UV_EADDRINUSE error.

Additionally, stop the timer only if we succeed or on hard error via
isc__nm_failed_connect_cb().

(cherry picked from commit b21f507c0ac5b5d2d2c27fd2d71e27e8605dd5fc)
2022-07-14 21:47:47 +02:00
Mark Andrews
937794c2da disassociate rdatasets when cleaning up
free_namelist could be passed names with associated rdatasets
when handling errors.  These need to be disassociated before
calling dns_message_puttemprdataset.

(cherry picked from commit 745d5edc3a8ca6f232b2d700ae076c2caee2bfc5)
2022-07-14 10:21:38 +10:00
Michał Kępień
b855c6b6c9 Stop resolving invalid names in resume_dslookup()
Commit 7b2ea97e46 introduced a logic bug
in resume_dslookup(): that function now only conditionally checks
whether DS chasing can still make progress.  Specifically, that check is
only performed when the previous resume_dslookup() call invokes
dns_resolver_createfetch() with the 'nameservers' argument set to
something else than NULL, which may not always be the case.  Failing to
perform that check may trigger assertion failures as a result of
dns_resolver_createfetch() attempting to resolve an invalid name.

Example scenario that leads to such outcome:

 1. A validating resolver is configured to forward all queries to
    another resolver.  The latter returns broken DS responses that
    trigger DS chasing.

 2. rctx_chaseds() calls dns_resolver_createfetch() with the
    'nameservers' argument set to NULL.

 3. The fetch fails, so resume_dslookup() is called.  Due to
    fevent->result being set to e.g. DNS_R_SERVFAIL, the default branch
    is taken in the switch statement.

 4. Since 'nameservers' was set to NULL for the fetch which caused the
    resume_dslookup() callback to be invoked
    (fctx->nsfetch->private->nameservers), resume_dslookup() chops off
    one label off fctx->nsname and calls dns_resolver_createfetch()
    again, for a name containing one label less than before.

 5. Steps 3-4 are repeated (i.e. all attempts to find the name servers
    authoritative for the DS RRset being chased fail) until fctx->nsname
    becomes stripped down the the root name.

 6. Since resume_dslookup() does not check whether DS chasing can still
    make progress, it strips off a label off the root name and continues
    its attempts at finding the name servers authoritative for the DS
    RRset being chased, passing an invalid name to
    dns_resolver_createfetch().

Fix by ensuring resume_dslookup() always checks whether DS chasing can
still make progress when a name server fetch fails.  Update code
comments to ensure the purpose of the relevant dns_name_equal() check is
clear.

(cherry picked from commit 1a79aeab44)
2022-07-13 11:00:32 +02:00