This release offers 100% line and branch coverage.
- Made ServiceInfo first question QU (\852) bdraco
We want an immediate response when requesting with ServiceInfo by
asking a QU question; most responders will not delay the response
and respond right away to our question. This also improves
compatibility with split networks as we may not have been able to
see the response otherwise. If the responder has not multicast the
record recently, it may still choose to do so in addition to
responding via unicast
Reduces traffic when there are multiple zeroconf instances running
on the network running ServiceBrowsers
If we don't get an answer on the first try, we ask a QM question in
the event, we can't receive a unicast response for some reason
This change puts ServiceInfo inline with ServiceBrowser which also
asks the first question as QU since ServiceInfo is commonly called
from ServiceBrowser callbacks
- Limited duplicate packet suppression to 1s intervals (\841) bdraco
Only suppress duplicate packets that happen within the same second.
Legitimate queriers will retry the question if they are suppressed.
The limit was reduced to one second to be in line with rfc6762
- Made multipacket known answer suppression per interface (\836)
bdraco
The suppression was happening per instance of Zeroconf instead of
per interface. Since the same network can be seen on multiple
interfaces (usually and wifi and ethernet), this would confuse the
multi-packet known answer supression since it was not expecting to
get the same data more than once
- New ServiceBrowsers now request QU in the first outgoing when
unspecified (\812) bdraco
<https://datatracker.ietf.org/doc/html/rfc6762#section-5.4> When we
start a ServiceBrowser and zeroconf has just started up, the known
answer list will be small. By asking a QU question first, it is
likely that we have a large known answer list by the time we ask the
QM question a second later (current default which is likely too low
but would be a breaking change to increase). This reduces the amount
of traffic on the network, and has the secondary advantage that most
responders will answer a QU question without the typical delay
answering QM questions.
- IPv6 link-local addresses are now qualified with scope\_id (\343)
ibygrave
When a service is advertised on an IPv6 address where the scope is
link local, i.e. fe80::/64 (see RFC 4007) the resolved IPv6 address
must be extended with the scope\_id that identifies through the "%"
symbol the local interface to be used when routing to that address.
A new API <span class="title-ref">parsed\_scoped\_addresses()</span>
is provided to return qualified addresses to avoid breaking
compatibility on the existing parsed\_addresses().
- Network adapters that are disconnected are now skipped (\327)
ZLJasonG
- Fixed listeners missing initial packets if Engine starts too quickly
(\387) bdraco
When manually creating a zeroconf.Engine object, it is no longer
started automatically. It must manually be started by calling
.start() on the created object.
The Engine thread is now started after all the listeners have been
added to avoid a race condition where packets could be missed at
startup.
- Fixed answering matching PTR queries with the ANY query (\618)
bdraco
- Fixed lookup of uppercase names in the registry (\597) bdraco
If the ServiceInfo was registered with an uppercase name and the
query was for a lowercase name, it would not be found and
vice-versa.
- Fixed unicast responses from any source port (\598) bdraco
Unicast responses were only being sent if the source port was 53,
this prevented responses when testing with dig:
> dig -p 5353 224.0.0.251 media-12.local
The above query will now see a response
- Fixed queries for AAAA records not being answered (\616) bdraco
- Removed second level caching from ServiceBrowsers (\737) bdraco
The ServiceBrowser had its own cache of the last time it saw a
service that was reimplementing the DNSCache and presenting a source
of truth problem that lead to unexpected queries when the two
disagreed.
- Fixed server cache not being case-insensitive (\731) bdraco
If the server name had uppercase chars and any of the matching
records were lowercase, and the server would not be found
- Fixed cache handling of records with different TTLs (\729) bdraco
There should only be one unique record in the cache at a time as
having multiple unique records will different TTLs in the cache can
result in unexpected behavior since some functions returned all
matching records and some fetched from the right side of the list to
return the newest record. Instead we now store the records in a dict
to ensure that the newest record always replaces the same unique
record, and we never have a source of truth problem determining the
TTL of a record from the cache.
- Fixed ServiceInfo with multiple A records (\725) bdraco
If there were multiple A records for the host, ServiceInfo would
always return the last one that was in the incoming packet, which
was usually not the one that was wanted.
- Fixed stale unique records expiring too quickly (\706) bdraco
Records now expire 1s in the future instead of instant removal.
tools.ietf.org/html/rfc6762\section-10.2 Queriers receiving a
Multicast DNS response with a TTL of zero SHOULD NOT immediately
delete the record from the cache, but instead record a TTL of 1 and
then delete the record one second later. In the case of multiple
Multicast DNS responders on the network described in Section 6.6
above, if one of the responders shuts down and incorrectly sends
goodbye packets for its records, it gives the other cooperating
responders one second to send out their own response to "rescue" the
records before they expire and are deleted.
- Fixed exception when unregistering a service multiple times (\679)
bdraco
- Added an AsyncZeroconfServiceTypes to mirror ZeroconfServiceTypes to
zeroconf.asyncio (\658) bdraco
- Fixed interface\_index\_to\_ip6\_address not skiping ipv4 adapters
(\651) bdraco
- Added async\_unregister\_all\_services to AsyncZeroconf (\649)
bdraco
- Fixed services not being removed from the registry when calling
unregister\_all\_services (\644) bdraco
There was a race condition where a query could be answered for a
service in the registry, while goodbye packets which could result in
a fresh record being broadcast after the goodbye if a query came in
at just the right time. To avoid this, we now remove the services
from the registry right after we generate the goodbye packet
- Fixed zeroconf exception on load when the system disables IPv6
(\624) bdraco
- Fixed the QU bit missing from for probe queries (\609) bdraco
The bit should be set per
datatracker.ietf.org/doc/html/rfc6762\section-8.1
- Fixed the TC bit missing for query packets where the known answers
span multiple packets (\494) bdraco
- Fixed packets not being properly separated when exceeding maximum
size (\498) bdraco
Ensure that questions that exceed the max packet size are moved to
the next packet. This fixes DNSQuestions being sent in multiple
packets in violation of:
datatracker.ietf.org/doc/html/rfc6762\section-7.2
Ensure only one resource record is sent when a record exceeds
\_MAX\_MSG\_TYPICAL
datatracker.ietf.org/doc/html/rfc6762\section-17
- Fixed PTR questions asked in uppercase not being answered (\465)
bdraco
- Added Support for context managers in Zeroconf and AsyncZeroconf
(\284) shenek
- Implemented an AsyncServiceBrowser to compliment the sync
ServiceBrowser (\429) bdraco
- Added async\_get\_service\_info to AsyncZeroconf and async\_request
to AsyncServiceInfo (\408) bdraco
- Implemented allowing passing in a sync Zeroconf instance to
AsyncZeroconf (\406) bdraco
- Fixed IPv6 setup under MacOS when binding to "" (\392) bdraco
- Fixed ZeroconfServiceTypes.find not always cancels the
ServiceBrowser (\389) bdraco
There was a short window where the ServiceBrowser thread could be
left running after Zeroconf is closed because the .join() was never
waited for when a new Zeroconf object was created
- Fixed duplicate packets triggering duplicate updates (\376) bdraco
If TXT or SRV records update was already processed and then received
again, it was possible for a second update to be called back in the
ServiceBrowser
- Fixed ServiceStateChange.Updated event happening for IPs that
already existed (\375) bdraco
- Fixed RFC6762 Section 10.2 paragraph 2 compliance (\374) bdraco
- Reduced length of ServiceBrowser thread name with many types (\373)
bdraco
- Fixed empty answers being added in ServiceInfo.request (\367)
bdraco
- Fixed ServiceInfo not populating all AAAA records (\366) bdraco
Use get\_all\_by\_details to ensure all records are loaded into
addresses.
Only load A/AAAA records from the cache once in load\_from\_cache if
there is a SRV record present
Move duplicate code that checked if the ServiceInfo was complete
into its own function
- Fixed a case where the cache list can change during iteration
(\363) bdraco
- Return task objects created by AsyncZeroconf (\360) nocarryr
Traffic Reduction:
- Added support for handling QU questions (\621) bdraco
Implements RFC 6762 sec 5.4: Questions Requesting Unicast Responses
datatracker.ietf.org/doc/html/rfc6762\section-5.4
- Implemented protect the network against excessive packet flooding
(\619) bdraco
- Additionals are now suppressed when they are already in the answers
section (\617) bdraco
- Additionals are no longer included when the answer is suppressed by
known-answer suppression (\614) bdraco
- Implemented multi-packet known answer supression (\687) bdraco
Implements datatracker.ietf.org/doc/html/rfc6762\section-7.2
- Implemented efficient bucketing of queries with known answers
(\698) bdraco
- Implemented duplicate question suppression (\770) bdraco
<http://datatracker.ietf.org/doc/html/rfc6762#section-7.3>
Technically backwards incompatible:
- Update internal version check to match docs (3.6+) (\491) bdraco
Python version earlier then 3.6 were likely broken with zeroconf
already, however, the version is now explicitly checked.
- Update python compatibility as PyPy3 7.2 is required (\523) bdraco
Backwards incompatible:
- Drop oversize packets before processing them (\826) bdraco
Oversized packets can quickly overwhelm the system and deny service
to legitimate queriers. In practice, this is usually due to broken
mDNS implementations rather than malicious actors.
- Guard against excessive ServiceBrowser queries from PTR records
significantly lowerthan recommended (\824) bdraco
We now enforce a minimum TTL for PTR records to avoid
ServiceBrowsers generating excessive queries refresh queries. Apple
uses a 15s minimum TTL, however, we do not have the same level of
rate limit and safeguards, so we use 1/4 of the recommended value.
- RecordUpdateListener now uses async\_update\_records instead of
update\_record (\419, \726) bdraco
This allows the listener to receive all the records that have been
updated in a single transaction such as a packet or cache expiry.
update\_record has been deprecated in favor of
async\_update\_records A compatibility shim exists to ensure classes
that use RecordUpdateListener as a base class continue to have
update\_record called, however, they should be updated as soon as
possible.
A new method async\_update\_records\_complete is now called on each
listener when all listeners have completed processing updates and
the cache has been updated. This allows ServiceBrowsers to delay
calling handlers until they are sure the cache has been updated as
its a common pattern to call for ServiceInfo when a ServiceBrowser
handler fires.
The async\_ prefix was chosen to make it clear that these functions
run in the eventloop and should never do blocking I/O. Before 0.32+
these functions ran in a select() loop and should not have been
doing any blocking I/O, but it was not clear to implementors that
I/O would block the loop.
- Pass both the new and old records to async\_update\_records (\792)
bdraco
Pass the old\_record (cached) as the value and the new\_record
(wire) to async\_update\_records instead of forcing each consumer to
check the cache since we will always have the old\_record when
generating the async\_update\_records call. This avoids the overhead
of multiple cache lookups for each listener.