- a bug that was already fixed in tcpdns.c and tlsdns.c had been
left unfixed in tcp.c: we needed to check whether the socket() call
succeeds before attempting any asynchronous connection code.
this corrects a problem that occurred when uv__socket() failed
with too many open files.
- also corrected the behavior of nm_connectcb(). previously, it was
forcing synchronous execution when force_async was false. what we
want is to force asynchronous execution if force_async is true. if
force_async is false, we want it to decide based on whether we're in
the network thread.
isc_nm_httprequest() is retained for use by doh_test, but has
been renamed isc__nm_http_request() and is no longer part of
the main API.
eventually doh_test should be changed to use isc_nm_read() and
isc_nm_send(), and this function should be removed.
we don't want to call isc__nm_http_cleanup_data() for TLS sockets
or isc__nm_tls_cleanup_data() for HTTP sockets, they can step on
each other and cause a crash or deadlock.
this isn't working yet, but it's a step in the right direction:
we need to call the connect callback from isc_nm_httpconnect()
asynchronously, after the connect has already returned. this
will enable dig to unlock the lookup before tcp_connected()
locks it, as it does when using tcpdns or tlsdns sockets.
this commit also removes the http_connect_t structure and stores
the connection data in a newly created http socket instead. (since
the socket structure was going to be needed to call isc__nm_connectcb()
anyway, it seemed like a good idea to make use of it to simplify
the connection code.)
in tls_call_connect_cb(), we want to update the result for
the TLS socket. however, in some error conditions on connect,
the handle we're passing is for the TCP socket instead. this
was causing the wrong socket's result code to be updated, and
the thread that was waiting for the result to be updated never
woke up.
(note: while the fix in this commit causes doh_test to stop
deadlocking, I'm not sure whether I've actually fixed the bug.
in other places, we create a new 'tlshandle' to pass into
tls_call_connect_cb(). perhaps we should be doing that in
all cases?)
incidentally, I also renamed tls_connect_cb() to tcp_connected(),
because the handle passed in is for the TCP socket, and I kept
being confused by the name having "tls" in it.
the goal here is to have the interface to http sockets be
the same as other types of netmgr socket, so that (for
example) dig can open an http connection and then just work
with no further code change, the same as it does with tcpdns
or tlsdns.
but the supporting code for https seems to be written with
the assumption that there will be a tight connection between
a request and a response, so the send and read functions have been
compressed into a single 'httprequest' function call. in an effort
to make the normal send and read semantics work correctly, we're
trying to set it up so that read sets us up to listen for a
response, send sets up the query we're sending, and whichever one
comes second triggers the transaction.
currently this is working in doh_test, but dig is failing due to a
deadlock; isc_http_connect() needs to return so launch_next_query()
can unlock the lookup before tcp_connected() runs.
instead of setting up ALPN in isc_tlsctx_createclient(), we now
have a function isc_tlsctx_enable_http2client_alpn() that can be
run from isc_nm_httpconnect(). isc_tlsctx_enable_http2server_alpn()
can similarly be run from isc_nm_httpconnect().
- style, cleanup, and removal of unnecessary code
- combine isc_nm_http_add_endpoint() and isc_nm_http_add_doh_endpoint()
into one function, renamed isc_http_endpoint()
- move isc_nm_http_connect_send_request() into doh_test.c as a helper
function; remove it from the public API
- renamed isc_http2 and isc_nm_http2 entities to just isc_http and
isc_nm_http, for consistency with other existing names
- shortened a number of long names
- the caller is now responsible for determining the peer address
in isc_nm_httpconnect(); this eliminates the need to parse the URI
and the dependency on an external resolver. the caller is also now
responsible for creating the SSL client context, for consistency with
isc_nm_tlsdnsconnect().
Three small cleanups:
1. Remove an unused keystr/dst_key_format.
2. Initialize a dst_key_state_t state with NA.
3. Update false comment about local policy (local policy only adds
barrier on transitions to the RUMOURED state, not the UNRETENTIVE
state).
There was a bug in function 'keymgr_ds_hidden_or_chained()'.
The funcion 'keymgr_ds_hidden_or_chained()' implements (3e) of rule2
as defined in the "Flexible and Robust Key Rollover" paper. The rules
says: All DS records need to be in the HIDDEN state, or if it is not
there must be a key with its DNSKEY and KRRSIG in OMNIPRESENT, and
its DS in the same state as the key in question. In human langauge,
if all keys have their DS in HIDDEN state you can do what you want,
but if a DS record is available to some validators, there must be
a chain of trust for it.
Note that the barriers on transitions first check if the current
state is valid, and then if the next state is valid too. But
here we falsely updated the 'dnskey_omnipresent' (now 'dnskey_chained')
with the next state. The next state applies to 'key' not to the state
to be checked. Updating the state here leads to (true) always, because
the key that will move its state will match the falsely updated
expected state. This could lead to the assumption that Key 2 would be
a valid chain of trust for Key 1, while clearly the presence of any
DS is uncertain.
The fix here is to check if the DNSKEY and KRRSIG are in OMNIPRESENT
state for the key that does not have its DS in the HIDDEN state, and
only if that is not the case, ensure that there is a key with the same
algorithm, that provides a valid chain of trust, that is, has its
DNSKEY, KRRSIG, and DS in OMNIPRESENT state.
The changes in 'keymgr_dnskey_hidden_or_chained()' are only cosmetical,
renaming 'rrsig_omnipresent' to 'rrsig_chained' and removing the
redundant initialization of the DST_KEY_DNSKEY expected state to NA.
The previous commit changed the function definition of
'keymgr_key_is_successor()', this commit updates the code where
this function is called.
In 'keymgr_key_exists_with_state()' the logic is also updated slightly
to become more readable. First handle the easy cases:
- If the key does not match the state, continue with the next key.
- If we found a key with matching state, and there is no need to
check the successor relationship, return (true).
- Otherwise check the successor relationship.
In 'keymgr_key_has_successor()' it is enough to check if a key has
a direct successor, so instead of calling 'keymgr_key_is_successor()',
we can just check 'keymgr_direct_dep()'.
In 'dns_keymgr_run()', we want to make sure that there is no
dependency on the keys before retiring excess keys, so replace
'keymgr_key_is_successor()' with 'keymgr_dep()'.
So far the key manager could only deal with two keys in a rollover,
because it used a simplified version of the successor relationship
equation from "Flexible and Robust Key Rollover" paper. The simplified
version assumes only two keys take part in the key rollover and it
for that it is enough to check the direct relationship between two
keys (is key x the direct predecessor of key z and is key z the direct
successor of key x?).
But when a third key (or more keys) comes into the equation, the key
manager would assume that one key (or more) is redundant and removed
it from the zone prematurely.
Fix by implementing Equation(2) correctly, where we check for
dependencies on keys:
z ->T x: Dep(x, T) = ∅ ∧
(x ∈ Dep(z, T) ∨
∃ y ∈ Dep(z, T)(y != z ∧ y ->T x ∧ DyKyRySy = DzKzRzSz))
This says: key z is a successor of key x if:
- key x depends on key z if z is a direct successor of x,
- or if there is another key y that depends on key z that has identical
key states as key z and key y is a successor of key x.
- Also, key x may not have any other keys depending on it.
This is still a simplified version of Equation(2) (but at least much
better), because the paper allows for a set of keys to depend on a
key. This is defined as the set Dep(x, T). Keys in the set Dep(x, T)
have a dependency on key x for record type T. The BIND implementation
can only have one key in the set Dep(x, T). The function
'keymgr_dep()' stores this key in 'uint32_t *dep' if there is a
dependency.
There are two scenarios where multiple keys can depend on a single key:
1. Rolling keys is faster than the time required to finish the
rollover procedure. This scenario is covered by the recursive
implementation, and checking for a chain of direct dependencies
will suffice.
2. Changing the policy, when a zone is requested to be signed with
a different key length for example. BIND 9 will not mark successor
relationships in this case, but tries to move towards the new
policy. Since there is no successor relationship, the rules are
even more strict, and the DNSSEC reconfiguration is actually slower
than required.
Note: this commit breaks the build, because the function definition
of 'keymgr_key_is_successor' changed. This will be fixed in the
following commit.
*** CID 318094: Null pointer dereferences (REVERSE_INULL)
/lib/dns/rbtdb.c: 1389 in newversion()
1383 version->xfrsize = rbtdb->current_version->xfrsize;
1384 RWUNLOCK(&rbtdb->current_version->rwlock, isc_rwlocktype_read);
1385 rbtdb->next_serial++;
1386 rbtdb->future_version = version;
1387 RBTDB_UNLOCK(&rbtdb->lock, isc_rwlocktype_write);
1388
CID 318094: Null pointer dereferences (REVERSE_INULL)
Null-checking "version" suggests that it may be null, but it has already been dereferenced on all paths leading to the check.
1389 if (version == NULL) {
1390 return (result);
1391 }
1392
1393 *versionp = version;
1394
removed the isc_cfg_http_t and isc_cfg_tls_t structures
and the functions that loaded and accessed them; this can
be done using normal config parser functions.
This commit contains fixes to unit tests to make them work well on
various platforms (in particular ones shipping old versions of
OpenSSL) and for different configurations.
It also updates the generated manpage to include DoH configuration
options.
This commit completes the support for DNS-over-HTTP(S) built on top of
nghttp2 and plugs it into the BIND. Support for both GET and POST
requests is present, as required by RFC8484.
Both encrypted (via TLS) and unencrypted HTTP/2 connections are
supported. The latter are mostly there for debugging/troubleshooting
purposes and for the means of encryption offloading to third-party
software (as might be desirable in some environments to simplify TLS
certificates management).
This commit includes work-in-progress implementation of
DNS-over-HTTP(S).
Server-side code remains mostly untested, and there is only support
for POST requests.
This commit adds stub parser support and tests for:
- an "http" global option for HTTP/2 endpoint configuration.
- command line options to set http or https port numbers by
specifying -p http=PORT or -p https=PORT. (NOTE: this change
only affects syntax; specifying HTTP and HTTPS ports on the
command line currently has no effect.)
- named.conf options "http-port" and "https-port"
- HTTPSPORT environment variable for use when running tests.
This commit resurrects the old TLS code from
8f73c70d23.
It also includes numerous stability fixes and support for
isc_nm_cancelread() for the TLS layer.
The code was resurrected to be used for DoH.
The 'key_init()' function is used to initialize a state file for keys
that don't have one yet. This can happen if you are migrating from a
'auto-dnssec' or 'inline-signing' to a 'dnssec-policy' configuration.
It did not look at the "Inactive" and "Delete" timing metadata and so
old keys left behind in the key directory would also be considered as
a possible active key. This commit fixes this and now explicitly sets
the key goal to OMNIPRESENT for keys that have their "Active/Publish"
timing metadata in the past, but their "Inactive/Delete" timing
metadata in the future. If the "Inactive/Delete" timing metadata is
also in the past, the key goal is set to HIDDEN.
If the "Inactive/Delete" timing metadata is in the past, also the
key states are adjusted to either UNRETENTIVE or HIDDEN, depending on
how far in the past the metadata is set.
Add support for a "tls" key/value pair for zone primaries, referencing
either a "tls" configuration statement or "ephemeral". If set to use
TLS, zones will send SOA and AXFR/IXFR queries over a TLS channel.
This commit fix a race that could happen when two or more threads have
failed to refresh the same RRset, the threads could simultaneously
attempt to update the header->last_refresh_fail_ts field in
check_stale_header, a field used to implement stale-refresh-time.
By making this field atomic we avoid such race.
If we did not attempt a fetch due to fetch-limits, we should not start
the stale-refresh-time window.
Introduce a new flag DNS_DBFIND_STALESTART to differentiate between
a resolver failure and unexpected error. If we are resuming, this
indicates a resolver failure, then start the stale-refresh-time window,
otherwise don't start the stale-refresh-time window, but still fall
back to using stale data.
(This commit also wraps some docstrings to 80 characters width)
Before this change, BIND will only fallback to using stale data if
there was an actual attempt to resolve the query. Then on a timeout,
the stale data from cache becomes eligible.
This commit changes this so that on any unexpected error stale data
becomes eligble (you would still have to have 'stale-answer-enable'
enabled of course).
If there is no stale data, this may return in an error again, so don't
loop on stale data lookup attempts. If the DNS_DBFIND_STALEOK flag is
set, this means we already tried to lookup stale data, so if that is
the case, don't use stale again.
