when built with "configure --enable-singletrace", named will produce
detailed query logging at the highest debug level for any query with
query ID zero.
this enables monitoring of the progress of a single query by specifying
the QID using "dig +qid=0". the "client" logging category should be set
to a low severity level to suppress logging of other queries. (the
chance of another query using QID=0 at the same time is only 1 in 2^16.)
"--enable-singletrace" turns on "--enable-querytrace" as well, so if the
logging severity is not lowered, all other queries will be logged
verbosely as well. compiling with either of these options will impair
query performance; they should only be turned on when testing or
troubleshooting.
Replace an existing comment with a more verbose explanation of when the
"hint" variable is set in resquery_send() and how its value affects the
advertised UDP buffer size in outgoing queries.
If "edns-udp-size" is set in a "server" block matching the queried
server, it is accounted for in the process of determining the advertised
UDP buffer size, but its value may still be overridden before the query
is sent. This behavior contradicts the ARM which claims that when set,
the server-specific "edns-udp-size" value is used for all EDNS queries
sent to a given server.
Furthermore, calling dns_peer_getudpsize() with the "udpsize" variable
as an argument makes the code hard to follow as that call may either
update the value of "udpsize" or leave it untouched.
Ensure the code matches the documentation by moving the
dns_peer_getudpsize() call below all other blocks of code potentially
affecting the advertised UDP buffer size, which is where it was located
when server-specific "edns-udp-size" support was first implemented [1].
Improve code readability by calling dns_peer_getudpsize() with a helper
variable instead of "udpsize".
[1] see commit 1c153afce5
When the DNS_FETCHOPT_EDNS512 flag was first introduced [1], it enforced
advertising a 512-byte UDP buffer size in an outgoing query. Ever since
EDNS processing code got updated [2], that flag has still been set upon
detection of certain query timeout patterns, but it has no longer been
affecting the calculations of the advertised UDP buffer size in outgoing
queries. Restore original semantic meaning of DNS_FETCHOPT_EDNS512 by
ensuring the advertised UDP buffer size is set to 512 bytes when that
flag is set. Update existing comments and add new ones to improve code
readability.
[1] see commit 08c9026166
[2] see commit 8e15d5eb3a
The following message:
success resolving '<name>' (in '<domain>'?) after reducing the advertised EDNS UDP packet size to 512 octets
can currently be logged even if the EDNS UDP buffer size advertised in
queries sent to a given server had already been set to 512 octets before
the fetch context was created (e.g. due to the server responding
intermittently). In other words, this log message may be misleading as
lowering the advertised EDNS UDP buffer size may not be the actual cause
of <name> being successfully resolved. Remove the log message in
question to prevent confusion.
As this log message is the only existing user of the "reason" field in
struct fetchctx, remove that field as well, along with all the code
related to it.
This adds a unit test driver for BIND with Automake. It runs the unit
test program provided as its sole command line argument and then looks
for a core dump generated by that test program. If one is found, the
driver prints the backtrace into the test log.
In process_fd we lock sock->lock and then internal_accept locks mgr->lock,
in isc_sockmgr_render* functions we lock mgr->lock and then lock sock->lock,
that can cause a deadlock when accessing stats. Unlock sock->lock early in
all the internal_{send,recv,connect,accept} functions instead of late
in process_fd.
If there are more that 5 NS record for a zone only perform a
maximum of 4 address lookups for all the name servers. This
limits the amount of remote lookup performed for server
addresses at each level for a given query.
Instead of using bind() and passing the listening socket to the children
threads using uv_export/uv_import use one thread that does the accepting,
and then passes the connected socket using uv_export/uv_import to a random
worker. The previous solution had thundering herd problems (all workers
waking up on one connection and trying to accept()), this one avoids this
and is simpler.
The tcp clients quota is simplified with isc_quota_attach_cb - a callback
is issued when the quota is available.
nzf_append is conditionally compiled and this is intended to
catch error introduced by changes to the called functions on all
systems before the changes are run through the CI.
Per Current Mechanisms 2.3.5, the curve name is DER-encoded in the
EC_PARAMS attribute, and the public key value is DER-encoded in the
EC_POINT attribute.
Add recursive "test" and "unit" rules, which execute "make check"
in specific directories - "make test" runs the system tests, and
"make unit" runs the unit tests.
The libirs contained own re-implementations of the getaddrinfo,
getnameinfo and gai_strerror + irs_context and irs_dnsconf API that was
unused anywhere in the BIND 9.
Keep just the irs_resonf API that is being extensively used to parse
/etc/resolv.conf by several of BIND 9 tools.
The 'ephemeral' database implementation was used to provide a
lightweight database implemenation that doesn't cache results, and the
only place where it was really use is "samples" because delv is
overriding this to use "rbtdb" instead. Otherwise it was completely
unused.
* The 'ephemeral' cache DB (ecdb) implementation. An ecdb just provides
* temporary storage for ongoing name resolution with the common DB interfaces.
* It actually doesn't cache anything. The implementation expects any stored
* data is released within a short period, and does not care about the
* scalability in terms of the number of nodes.
The three libdns tests directly include ../dst_internal.h which
in turn directly include openssl headers, thus there was a missing
path and build failure on systems where OpenSSL is not in the default
include path.