We should return the errno value in such case, as ret will always be -1
on failure, which might misleading, as it does not give any hint on what
failed.
Also bump the log level of the error message, so the failure is visible
w/o needing to enable debug logs. Such a failure is fatal for the DNS
subsystem, so error level is justified here.
Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
The `dns_data` buffer, allocated by the DNS dispatcher was dereferenced
twice - once in registered DNS handler, second time in the dispatcher
itself.
Since the buffer was allocated by the dispatcher, and it's not really
guaranteed that the buffer will be freed in the registered handler (this
depends on the processing outcome, the function may return early w/o
freeing the net buf in case of errors), it makes most sense for the
dispatcher to keep ownership of the buffer. Hence, the registered
handlers will no longer release the buffer provided in any case, and the
dispatcher will free it on exit.
Signed-off-by: Robert Lubos <robert.lubos@nordicsemi.no>
Allow mDNS resolver and responder to to be used at the same
time so that both can use the port 5353. This requires
a DNS traffic dispatcher which affects also the normal DNS
resolver.
Fixes#72553
Signed-off-by: Jukka Rissanen <jukka.rissanen@nordicsemi.no>
If DNS_EAI_ALLDONE is returned, it indicates that the request
was done and should not be considered an error.
Signed-off-by: Jukka Rissanen <jukka.rissanen@nordicsemi.no>
Instead of using net_context API directly, the DNS resolver is
changed to use the socket service API. This allows DNS access
for offloaded sockets and can lower overall memory consumption.
Signed-off-by: Jukka Rissanen <jukka.rissanen@nordicsemi.no>
The size field in net_buf should not be used directly as then
the optional headroom will not be taken into account.
There is the net_buf_max_len() API that should be used instead.
Signed-off-by: Jukka Rissanen <jukka.rissanen@nordicsemi.no>
In order to reduce dns resolve requests when using the dns
resolver an optional cache was introduced. This cache
retains query requests for the TTL duration and therefore
prevents premature refetching of DNS RRs.
Signed-off-by: Carlo Kirchmeier <carlo.kirchmeier@zuehlke.com>
Adds an option to disable the automatic initialization of the default
dns_context. This lets applications use the default context, while also
managing the `init` and `close` functions.
Signed-off-by: Jordan Yates <jordan.yates@data61.csiro.au>
We specifically set TTL/hoplimit to 1 for LLMNR,
but only want to set it if in that specific case.
We must not pass TTL/hoplimit value 0 as that would
cause the packet to be dropped.
Signed-off-by: Jukka Rissanen <jukka.rissanen@nordicsemi.no>
rand32.h does not make much sense, since the random subsystem
provides more APIs than just getting a random 32 bits value.
Rename it to random.h and get consistently with other
subsystems.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
In dns_resolve_reconfigure() check if the DNS servers already exist
before cancel all ongoing queries. This will solve an issue with
getaddrinfo() returning DNS_EAI_CANCELED when receiving a retransmitted
DHCP offer and when receiving a IPv6 Router Advertisement.
Signed-off-by: Stig Bjørlykke <stig.bjorlykke@nordicsemi.no>
When a query is done, the query isn't set to NULL.
This can cause a nullptr exception in invoke_query_callback().
Signed-off-by: Jeroen van Dooren <jeroen.van.dooren@nobleo.nl>
If user has not specified any DNS servers in
CONFIG_DNS_SERVER_IP_ADDRESSES, then the DNS resolver will not be
initialized properly. So fix this by always calling dns_resolve_init()
so that DNS mutex get properly initialized.
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
This commit adds a check, in the `dns_read` function, before
dereferencing the query index returned by the `dns_validate_msg`
function.
This fixes the warnings generated by the GCC 12 such as:
error: array subscript -1 is below array bounds of
'struct dns_pending_query[5]' [-Werror=array-bounds]
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
Logging v1 has been removed and log_strdup wrapper function is no
longer needed. Removing the function and its use in the tree.
Signed-off-by: Krzysztof Chruscinski <krzysztof.chruscinski@nordicsemi.no>
Return ret error code instead of always returning zero causing
warnings:
...
subsys/net/lib/dns/resolve.c:975:6: warning: variable 'ret' set but
not used [-Wunused-but-set-variable]
int ret = 0;
^
...
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
In order to bring consistency in-tree, migrate all subsystems code to
the new prefix <zephyr/...>. Note that the conversion has been scripted,
refer to zephyrproject-rtos#45388 for more details.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
A common pattern here was to take the work item as the subfield of a
containing object. But the contained field is not a k_work, it's a
k_work_delayable.
Things were working only because the work field was first, so the
pointers had the same value. Do things right and fix things to
produce correct code if/when that field ever moves within delayable.
Signed-off-by: Yong Cong Sin <yongcong.sin@gmail.com>
Fixed mutli-IP DNS resolution as previously the same IP address was
used to populate all AI entries and added DNS_RESOLVER_AI_MAX_ENTRIES
config entry to define max number of IP addresses per DNS name to be
handled.
Signed-off-by: Ievgen Glinchuk <john.iceblink@gmail.com>
So far there was no dedicated mechanism for replacing DNS servers with
new list. Add dns_resolve_reconfigure() API that allows to achieve that
in a thread-safe manner.
Introduce 3rd state in DNS context lifetime by converting from 'bool
is_used' to 'enum dns_resolve_context_state state'. This new
DEACTIVATING state allows to mark a DNS context as busy and safely close
context without holding lock. Closing DNS context with released lock
prevents deadlock in case net_context_close() has to synchronize with a
separate thread executing handler passed to net_context_recv() (which is
the case for example with ESP-AT WiFi driver).
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
ctx->is_used member seemed to be used sometimes within a mutex acquired
block, sometimes not. Make it consistent by always using it with
acquired mutex.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
Query timeout handler is rescheduled if DNS context mutex is locked. So
far there was no timeout used, which means that work is simply put at
the end of system workqueue. This solves cases when mutex is locked by
any higher priority cooperative threads.
If however mutex was locked in application code within lower priority
thread (which is very likely) and query timeout has expired in the
meantime, then system workqueue is busy looping by calling query timeout
handler and trying to acquire DNS context lock.
Reschedule query timeout handler with 10ms delay, so that all
threads, including those with lower priorities, have a chance to move
forward and release DNS context lock.
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
Switch to the new API for delayed work related to DNS queries.
In the previous solution it was assumed that the work item could be
immediately cancelled at the point the query slot was released. This
is not true. We need a secondary condition to record the fact that
the query was completed while the work item was still pending, and an
additional check to detect when the work item completed and the slot
reclaimed.
Also annotate functions to indicate when they require the lock on
query content to be held, add some helpers that abstract core
operations like invoking a callback or releasing a query slot, and fix
some more cases where query slot content was accessed outside of the
new lock infrastructure.
Signed-off-by: Peter Bigot <peter.bigot@nordicsemi.no>
It is documented that using transient information like whether a work
item is pending or a delayed work item has time left to determine the
state of the work item before subsequent reconfiguration is prone to
race conditions, and known to produce unexpected behavior in the
presence of preemptive threads, SMP, or use of the work item from
interrupts. As a best practice such pre-validation steps should be
avoided unless algorithmically necessary.
All comparisons of remaining delayed time before canceling a delayed
work item in this module appear to be optimizations subject to the
above race conditions. Remove the checks so that only the inherent
race conditions in the implementation of canceling a work item remain.
Signed-off-by: Peter Bigot <peter.bigot@nordicsemi.no>
Add more tests to verify that we discard malformed packets.
In order to simplify the testing, separate message validation to
dns_validate_msg() function in resolve.c. Allow that function to
be called from unit test. This way we can construct invalid DNS
messages in unit test and verify that they are discarded when
needed.
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
-Wimplicit-fallthrough=2 requires a fallthrough comment or a compiler
to tells gcc that this happens intentionally.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
Unit tests were failing to build because random header was included by
kernel_includes.h. The problem is that rand32.h includes a generated
file that is either not generated or not included when building unit
tests. Also, it is better to limit the scope of this file to where it is
used.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
It might happen that while we are waiting for the response
to one of our query, we receive a query to resolve another name.
Previously this would make the current name resolution to fail because
only responses were expected to be received.
Signed-off-by: Léonard Bise <leonard.bise@gmail.com>
As mDNS requests set DNS id to 0, we cannot use it to match
the DNS response packet. In order to allow this functionality,
create a hash from query name and type, and use that together
with DNS id to match request and response.
Fixes#21914
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
If we are returned IPv4 address but the hints says IPv6, then
return error as currently we do not support AI_V4MAPPED addresses.
Same check for IPv6 if we want only IPv4 address.
Fixes#18870
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
The mDNS packet receive had issues:
* The DNS id needs to be 0 for both sending and receiving, we did
not accepted 0 incoming id.
* The mDNS response does not have any questions in it so we just
need to skip the question count checks in response.
* Skip the Cache-Flush bit in Class field so that we can properly
parse CLASS_IN value.
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
In DNS server init, print information whether the DNS server
is mDNS or LLMNR one. This way we do not need to remember what
IP addresses are used either of them.
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
The source UDP port in all Multicast DNS responses MUST be 5353
as described in RFC 6762 chapter 6.
Fixes#18732
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
If DNS server(s) are added or removed e.g., as part of DHCP
processing, send newly defined net-mgmt events so that
a user application may get this information.
Fixes#16924
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
And also to the relevant callbacks.
That parameter is not used anywhere so it is useless.
Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
Now that legacy functions are removew, let's rename the new functions by
removing the _new suffix.
Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
