MAX_RESTARTS is no longer hard-coded; ns_server_setmaxrestarts()
and dns_client_setmaxrestarts() can now be used to modify the
max-restarts value at runtime. in both cases, the default is 11.
Instead of calling dst_lib_init() and dst_lib_destroy() explicitly by
all the programs, create a separate memory context for the DST subsystem
and use the library constructor and destructor to initialize the DST
internals.
The OpenSSL 1.x Engines support has been deprecated in the OpenSSL 3.x
and is going to be removed. Remove the OpenSSL Engine support in favor
of OpenSSL Providers.
When adding glue to the header, we add header to the wait-free stack to
be cleaned up later which sets wfc_node->next to non-NULL value. When
the actual cleaning happens we would only cleanup the .glue_list, but
since the database isn't locked for the time being, the headers could be
reused while cleaning the existing glue entries, which creates a data
race between database versions.
Revert the code back to use per-database-version hashtable where keys
are the node pointers. This allows each database version to have
independent glue cache table that doesn't affect nodes or headers that
could already "belong" to the future database version.
dns_difftuple_create() could only return success, so change
its type to void and clean up all the calls to it.
other functions that only returned a result value because of it
have been cleaned up in the same way.
There isn't a realistic reason to ever use e = 4294967297. Fortunately
its codepath wasn't reachable to users and can be safetly removed.
Keep in mind the `dns_key_generate` header comment was outdated. e = 3
hasn't been used since 2006 so there isn't a reason to panic. The
toggle was the public exponents between 65537 and 4294967297.
Add support for using the offload threadpool to perform message
signature verifications. This should allow check SIG(0)-signed
messages without affecting the worker threads.
This is a tiny helper function which is used only once and can be
replaced with two function calls instead. Removing this makes
supporting asynchronous signature checking less complicated.
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.
Replace the ISC_LIST based deadnodes implementation with isc_queue which
is wait-free and we don't have to acquire neither the tree nor node lock
to append nodes to the queue and the cleaning process can also
copy (splice) the list into a local copy without acquiring the list.
Currently, there's little benefit to this as we need to hold those
locks anyway, but in the future as we move to RCU based implementation,
this will be ready.
To align the cleaning with our event loop based model, remove the
hardcoded count for the node locks and use the number of the event loops
instead. This way, each event loop can have its own cleaning as part of
the process. Use uniform random numbers to spread the nodes evenly
between the buckets (instead of hashing the domain name).
The `axfr_makedb()` didn't set the loop on the newly created database,
effectively killing delayed cleaning on such database. Move the
database creation into dns_zone API that knows all the gory details of
creating new database suitable for the zone.
when calling dns_qp_lookup() from qpcache, instead of passing
'foundname' so that a name would be constructed from the QP key,
we now just use the name field in the node data. this makes
dns_qp_lookup() run faster.
the same optimization has also been added to qpzone.
the documentation for dns_qp_lookup() has been updated to
discuss this performance consideration.
when the cache is over memory, we purge from the LRU list until
we've freed the approximate amount of memory to be added. this
approximation could fail because the memory allocated for nodenames
wasn't being counted.
add a dns_name_size() function so we can look up the size of nodenames,
then add that to the purgesize calculation.
in a cache database, unlike zones, NSEC3 records are stored in
the main tree. it is not necessary to maintain a separate 'nsec3'
tree, nor to have code in the dbiterator implementation to traverse
from one tree to another.
(if we ever implement synth-from-dnssec using NSEC3 records, we'll
need to revert this change. in the meantime, simpler code is better.)
- change dns_qpdata_t to qpcnode_t (QP cache node), and dns_qpdb_t to
qpcache_t, as these types are only accessed locally.
- also change qpdata_t in qpzone.c to qpznode_t (QP zone node), for
consistency.
- make the refcount declarations for qpcnode_t and qpznode_t static,
using the new ISC_REFCOUNT_STATIC macros.
the previous commit introduced a possible race in getsigningtime()
where the rdataset header could change between being found on the
heap and being bound.
getsigningtime() now looks at the first element of the heap, gathers the
locknum, locks the respective lock, and retrieves the header from the
heap again. If the locknum has changed, it will rinse and repeat.
Theoretically, this could spin forever, but practically, it almost never
will as the heap changes on the zone are very rare.
we simplify matters further by changing the dns_db_getsigningtime()
API call. instead of passing back a bound rdataset, we pass back the
information the caller actually needed: the resigning time, owner name
and type of the rdataset that was first on the heap.
Since the dns_validator_destroy() function doesn't guarantee that
it destroys the validator, rename it to dns_validator_shutdown()
and require explicit dns_validator_detach() to follow.
Enforce the documented function requirement that the validator must
be completed when the function is called.
Make sure to set val->name to NULL when the function is called,
so that the owner of the validator may destroy the name, even if
the validator is not destroyed immediately. This should be safe,
because the name can be used further only for logging by the
offloaded work callbacks when they detect that the validator is
already canceled/complete, and the logging function has a condition
to use the name only when it is non-NULL.
if we had a method to get the running loop, similar to how
isc_tid() gets the current thread ID, we can simplify loop
and loopmgr initialization.
remove most uses of isc_loop_current() in favor of isc_loop().
in some places where that was the only reason to pass loopmgr,
remove loopmgr from the function parameters.
because dns_qpmulti_commit() can be time consuming, it's inefficient
to open and commit a qpmulti transaction for each rdataset being loaded
into a database. we can improve load time by opening a qpmulti
transaction before adding a group of rdatasets and then committing it
afterward.
this commit adds 'setup' and 'commit' functions to dns_rdatacallbacks_t,
which can be called before and after the loops in which 'add' is
called in dns_master_load() and axfr_apply().
add database API method implementations needed to iterate and dump
a qpzone database to a file (createiterator, allrdatasets and
attachversion, plus dbiterator and rdatasetiter methods).
named-checkzone -D can now dump the contents of most zones,
but zone cuts are not correctly detected.
the dyndb test requires a mechanism to retrieve the name associated
with a database node, and since the database no longer uses RBT for
its underlying storage, dns_rbt_fullnamefromnode() doesn't work.
addressed this by adding dns_db_nodefullname() to the database API.
- Copy rbtdb.c, rbt-zonedb.c and rbt-cachedb.c to qp-*.
- Added qpmethods.
- Added a new structure dns_qpdata that will replace dns_rbtnode.
- Replaced normal, nsec, and nsec3 dns_rbt trees with dns_qp tries.
- Replaced dns_rbt_create() calls with dns_qp_create().
- Replaced the dns_rbt_destroy() call with dns_qp_destroy().
- Create a dns_qpdata struct and create/destroy methods.
This commit will not build.
The log message for commit 24381cc36d
explained:
In some older BIND 9 branches, the extra queuing overhead eliminated by
this change could be remotely exploited to cause excessive memory use.
Due to architectural shift, this branch is not vulnerable to that issue,
but applying the fix to the latter is nevertheless deemed prudent for
consistency and to make the code future-proof.
However, it turned out that having a single queue for the nodes to be
pruned increased lock contention to a level where cleaning up nodes from
the RBTDB took too long, causing the amount of memory used by the cache
to grow indefinitely over time.
This commit reverts the change to the pruning mechanism introduced by
commit 24381cc36d as BIND branches newer
than 9.16 were not affected by the excessive event queueing overhead
issue mentioned in the log message for the above commit.
- the DNS_DB_NSEC3ONLY and DNS_DB_NONSEC3 flags are mutually
exclusive; it never made sense to set both at the same time.
to enforce this, it is now a fatal error to do so. the
dbiterator implementation has been cleaned up to remove
code that treated the two as independent: if nonsec3 is
true, we can be certain nsec3only is false, and vice versa.
- previously, iterating a database backwards omitted
NSEC3 records even if DNS_DB_NONSEC3 had not been set. this
has been corrected.
- when an iterator reaches the origin node of the NSEC3 tree, we
need to skip over it and go to the next node in the sequence.
the NSEC3 origin node is there for housekeeping purposes and
never contains data.
- the dbiterator_test unit test has been expanded, several
incorrect expectations have been fixed. (for example, the
expected number of iterations has been reduced by one; we were
previously counting the NSEC3 origin node and we should not
have been doing so.)
- create_node() in rbt.c cannot fail
- the dns_rbt_*name() functions, which are wrappers around
dns_rbt_[add|find|delete]node(), were never used except in tests.
this change isn't really necessary since RBT is likely to go away
eventually anyway. but keeping the API as simple as possible while it
persists is a good thing, and may reduce confusion while QPDB is being
developed from RBTDB code.
these values pertain to whether a node is in the main, nsec, or nsec3
tree of an RBTDB. they need to be moved to a more generic location so
they can also be used by QPDB.
(this is in db.h rather than db_p.h because rbt.c needs access to it.
technically, that's a layer violation, but it's a long-existing one;
refactoring to get rid of it would be a large hassle, and eventually
we expect to remove rbt.c anyway.)
when the QPDB is implemented, we will need to have both qpdb_p.h and
rbtdb_p.h. in order to prevent name collisions or code duplication,
this commit adds a generic private header file, db_p.h, containing
structures and macros that will be used by both databases.
some functions and structs have been renamed to more specifically refer
to the RBT database, in order to avoid namespace collision with similar
things that will be needed by the QPDB later.
Expose the newly added 'first refresh' flag in the information
provided by the 'rndc staus' command, by showing the number of
zones, which are not yet fully ready, and their first refresh
is pending or is in-progress.
Add a new zone flag to indicate that a secondary type zone is
not yet fully ready, and a first time refresh is pending or is
in progress.
Expose this new flag in the statistics channel's "Incoming Zone
Transfers" section.
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.
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.
