Previously a hard-coded limitation of maximum two key or message
verification checks were introduced when checking the message's
SIG(0) signature. It was done in order to protect against possible
DoS attacks. The logic behind choosing the number two was that more
than one key should only be required only during key rotations, and
in that case two keys are enough. But later it became apparent that
there are other use cases too where even more keys are required, see
issue number #5050 in GitLab.
This change introduces two new configuration options for the views,
sig0key-checks-limit and sig0message-checks-limit, which define how
many keys are allowed to be checked to find a matching key, and how
many message verifications are allowed to take place once a matching
key has been found. The latter protects against expensive cryptographic
operations when there are keys with colliding tags and algorithm
numbers, with default being 2, and the former protects against a bit
less expensive key parsing operations and defaults to 16.
(cherry picked from commit 716b936045)
This new option sets a minimum amount of transfer rate for
an incoming zone transfer that will abort a transfer, which
for some network related reasons run very slowly.
(cherry picked from commit 91ea156203)
The 'remote-servers' named.conf reference conflicts with the standard
term from the glossary. Rename the standard term to server-list to
make the docs build.
(cherry picked from commit 726c9cd73b)
Add back the top blocks 'parental-agents', 'primaries', and 'masters'
to the configuration. Do not document them as so many names for the
same clause is confusing.
This has a slight negative side effect that a top block 'primaries'
can be referred to with a zone statement 'parental-agents' for example,
but that shouldn't be a big issue.
(cherry picked from commit 1b2eadb197)
Having zone statements that are also top blocks is confusing, and if
we want to add more in the future (which I suspect will be for
generalized notifications, multi-signer), we need to duplicate a lot
of code.
Remove top blocks 'parental-agents' and 'primaries' and just have one
top block 'remote-servers' that you can refer to with zone statements.
(cherry picked from commit b121f02eac)
Add a none parameter to named configuration option `query-source` (respectively `query-source-v6`) which forbid usage of IPv4 (respectively IPv6) addresses when named is doing an upstream query.
Closes#4981 Turning-off upstream IPv6 queries while still listening to downstream queries on IPv6.
Merge branch 'colin/querysource-none' into 'main'
See merge request isc-projects/bind9!9727
Backport of MR !9727
Some changes had to be done to the existing 9.20.x code in order to
make this backport compatible:
- first, the 9.20.x branches support the `port` parameter in
query-source[-v6], where 9.21.x does not. The original changes
depend on things that can't be backported because that would break
`port` support.
- second, the changes remove the optional `address` parameter from the
canonical form. So `query-source address <ip>` is now printed as
`query-source <ip>`. This means that `named-checkconf -p` will now
generate different output if users have `query-source address <ip>` or
`query-source address <ip> port <port>`; it will now generate
`query-source <ip>` or `query-source <ip> port <port>`. This is a
non-breaking change, because the parser has been updated to support
this form as well.
Add another option to configure how many outgoing queries per
client request is allowed. The existing 'max-recursion-queries' is
per restart, this one is a global limit.
(cherry picked from commit bbc16cc8e6)
When DSCP was removed the parsing of hostnames was accidentally
broken resulting in an assertion failure. Call cfg_parse_tuple
rather than using custom code in parse_sockaddrnameport.
(cherry picked from commit 6c095f89f5)
Log to the querylog the rcode of a previous query using
the identifier 'response:' to diffenciate queries from
responses.
(cherry picked from commit 5fad79c92f)
If neither libxml2 nor libjson_c are available have named-checkconf
fail if a statistics-channels block is specified.
(cherry picked from commit b9246418e8)
Add a new configuration option to enable Offline KSK key management.
Offline KSK cannot work with CSK because it splits how keys with the
KSK and ZSK role operate. Therefore, one key cannot have both roles.
Add a configuration check to ensure this.
(cherry picked from commit 0598381236)
As we now setup the logging very early, parsing the default config would
always print warnings about experimental (and possibly deprecated)
options in the default config. This would even mess with commands like
`named -V` and it is also wrong to warn users about using experimental
options in the default config, because they can't do anything about
this. Add CFG_PCTX_NODEPRECATED and CFG_PCTX_NOEXPERIMENTAL options
that we can pass to cfg parser and silence the early warnings caused by
using experimental options in the default config.
(cherry picked from commit 86f1ec34dc)
implement, document, and test the 'max-query-restarts' option
which specifies the query restart limit - the number of times
we can follow CNAMEs before terminating resolution.
(cherry picked from commit 104f3b82fb)
A different solution in the future might be adopted depending
on feedback and other new information, so it makes sense to mark
these options as EXPERIMENTAL until we have more data.
In order to protect from a malicious DNS client that sends many
queries with a SIG(0)-signed message, add a quota of simultaneously
running SIG(0) checks.
This protection can only help when named is using more than one worker
threads. For example, if named is running with the '-n 4' option, and
'sig0checks-quota 2;' is used, then named will make sure to not use
more than 2 workers for the SIG(0) signature checks in parallel, thus
leaving the other workers to serve the remaining clients which do not
use SIG(0)-signed messages.
That limitation is going to change when SIG(0) signature checks are
offloaded to "slow" threads in a future commit.
The 'sig0checks-quota-exempt' ACL option can be used to exempt certain
clients from the quota requirements using their IP or network addresses.
The 'sig0checks-quota-maxwait-ms' option is used to define a maximum
amount of time for named to wait for a quota to appear. If during that
time no new quota becomes available, named will answer to the client
with DNS_R_REFUSED.
Previously, the number of RR types for a single owner name was limited
only by the maximum number of the types (64k). As the data structure
that holds the RR types for the database node is just a linked list, and
there are places where we just walk through the whole list (again and
again), adding a large number of RR types for a single owner named with
would slow down processing of such name (database node).
Add a configurable limit to cap the number of the RR types for a single
owner. This is enforced at the database (rbtdb, qpzone, qpcache) level
and configured with new max-types-per-name configuration option that
can be configured globally, per-view and per-zone.
Previously, the number of RRs in the RRSets were internally unlimited.
As the data structure that holds the RRs is just a linked list, and
there are places where we just walk through all of the RRs, adding an
RRSet with huge number of RRs inside would slow down processing of said
RRSets.
Add a configurable limit to cap the number of the RRs in a single RRSet.
This is enforced at the database (rbtdb, qpzone, qpcache) level and
configured with new max-records-per-type configuration option that can
be configured globally, per-view and per-zone.
Be stricter in durations that are accepted. Basically we accept ISO 8601
formats, but fail to detect garbage after the integers in such strings.
For example, 'P7.5D' will be treated as 7 days. Pass 'endptr' to
'strtoll' and check if the endptr is at the correct suffix.
by default, QPDB is the database used by named and all tools and
unit tests. the old default of RBTDB can now be restored by using
"configure --with-zonedb=rbt --with-cachedb=rbt".
some tests have been fixed so they will work correctly with either
database.
CHANGES and release notes have been updated to reflect this change.
replace the string "rbt" throughout BIND with "qp" so that
qpdb databases will be used by default instead of rbtdb.
rbtdb databases can still be used by specifying "database rbt;"
in a zone statement.
Using the 'dnssec-validation yes' option now requires an explicitly
confgiured 'trust-anchors' statement (or 'managed-keys' or
'trusted-keys', both deprecated).
Instead of running all the cryptographic validation in a tight loop,
spread it out into multiple event loop "ticks", but moving every single
validation into own isc_async_run() asynchronous event. Move the
cryptographic operations - both verification and DNSKEY selection - to
the offloaded threads (isc_work_enqueue), this further limits the time
we spend doing expensive operations on the event loops that should be
fast.
Limit the impact of invalid or malicious RRSets that contain crafted
records causing the dns_validator to do many validations per single
fetch by adding a cap on the maximum number of validations and maximum
number of validation failures that can happen before the resolving
fails.
the 'low', 'high' and 'discount' parameters to 'fetch-quota-param'
are meant to be ratios with values between zero and one, but higher
values can be assigned. this could potentially lead to an assertion
in maybe_adjust_quota().
This is now the default way to implement attaching to/detaching from
a pointer.
Also update cfg_keystore_fromconfig() to allow NULL value for the
keystore pointer. In most cases we detach it immediately after the
function call.
Add a default key-directory parameter to the function that can
be returned if there is no keystore, or if the keystore directory
is NULL (the latter is also true for the built-in keystore).
The name "uri" was considered to be too generic and could potentially
clash with a future URI configuration option. Renamed to "pkcs11-uri".
Note that this option name was also preferred over "pkcs11uri", the
dash is considered to be the more clearer form.
If there is a keystore configured with a PKCS#11 URI, zones that
are using a dnssec-policy that uses such a keystore should create keys
via the PKCS#11 interface. Those keys are generally stored inside an
HSM.
Some changes to the code are required, to store the engine reference
into the keystore.
When creating the kasp structure, instead of storing the name of the
key store on keys, store a reference to the key store object instead.
This requires to build the keystore list prior to creating the kasp
structures, in the dnssec tools, the check code and the server code.
We will create a builtin keystore called "key-directory" which means
use the zone's key-directory as the key store.
The check code changes, because now the keystore is looked up before
creating the kasp structure (and if the keystore is not found, this
is an error). Instead of looking up the keystore after all
'dnssec-policy' clauses have been read.
Similar to key-directory, check for zones in different views and
different key and signing policies. Zones must be using different key
directories to store key files on disk.
Now that a key directory can be linked with a dnssec-policy key, the
'keydirexist' checking needs to be reshuffled.
Add tests for bad configuration examples, named-checkconf should catch
those. Also add test cases for a mix of key-directory and key-store
directory.
Similar to key-directory, check if the key-store directory exists and
if it is an actual directory.
This commit fixes an accidental test bug in checkconf where if
the "warn key-dir" test failed, the result was ignored.
Add checkconf check to ensure that the used key-store in the keys
section exists. Error if that is not the case. We also don't allow
the special keyword 'key-directory' as that is internally used to
signal that the zone's key-directory should be used.
Add code for configuring keystore objects. Add this to the "kaspconf"
code, as it is related to 'dnssec-policy' and it is too small to create
a separate file for it.
Add new configuration for setting key stores. The new 'key-store'
statement allows users to configure key store backends. These can be
of type 'file' (that works the same as 'key-directory') or of type
'pkcs11'. In the latter case, keys should be stored in a HSM that is
accessible through a PKCS#11 interface.
Keys configured within 'dnssec-policy' can now also use the 'key-store'
option to set a specific key store.
Update the checkconf test to accomodate for the new configuration.
Remove the CFG_CLAUSEFLAG_EXPERIMENTAL flag from the
"trust-anchor-telemetry" statement as the behavior of the latter has not
been changed since its initial implementation and there are currently no
plans to do so. This silences a relevant log message that was emitted
even when the feature was explicitly disabled.
