Zonemaster::Engine::Nameserver - object representing a DNS
nameserver
my $ns = Zonemaster::Engine::Nameserver->new({ name => 'ns.nic.se', address => '212.247.7.228' });
my $p = $ns->query('www.iis.se', 'AAAA');
This is a very central object in the Zonemaster::Engine framework.
All DNS communications with the outside world pass through here, so we can
do things like synthezising and recording traffic. All the objects are also
unique per name/IP pair, and creating a new one with an already existing
pair will return the existing object instead of creating a new one. Queries
and their responses are cached by IP address, so that a specific query will
only be sent once to each address (even if there are multiple objects for
that address with different names).
Class methods on this class allows saving and loading cache
contents.
- name
- A Zonemaster::Engine::DNSName object holding the nameserver's name.
- address
- A Zonemaster::Engine::Net::IP object holding the nameserver's
address.
- dns
- The Zonemaster::LDNS object used to actually send and receive DNS
queries.
- cache
- A reference to a Zonemaster::Engine::Nameserver::Cache object holding the
cache of sent queries. Not meant for external use.
- source_address
- The source address all resolver objects should use when sending
queries.
- times
- A reference to a list with elapsed time values for the queries made
through this nameserver.
- new
- Construct a new object.
- save($filename)
- Save the entire object cache to the given filename, using the
byte-order-independent Storable format.
- restore($filename)
- Replace the entire object cache with the contents of the named file.
- all_known_nameservers()
- Class method that returns a list of all nameserver objects in the global
cache.
- empty_cache()
- Remove all cached nameserver objects and queries.
- query($name,
$type, $flagref)
- Send a DNS query to the nameserver the object represents.
$name and $type are the
name and type that will be queried for ($type
defaults to 'A' if it's left undefined). $flagref
is a reference to a hash, the keys of which are flags and the values are
their corresponding values. The available flags are as follows. All but
the first directly correspond to methods in the Zonemaster::LDNS::Resolver
object.
- class
- Defaults to 'IN' if not set.
- usevc
- Send the query via TCP (only).
- retrans
- The retransmission interval
- dnssec
- Set the DO flag in the query.
- debug
- Set the debug flag in the resolver, producing output on STDERR as the
query process proceeds.
- recurse
- Set the RD flag in the query.
- timeout
- Set the timeout for the outgoing sockets. May or may not be observed by
the underlying network stack.
- retry
- Set the number of times the query is tried.
- igntc
- If set to true, incoming response packets with the TC flag set are not
automatically retried over TCP.
- fallback
- If set to true, incoming response packets with the TC flag set fall back
to EDNS and/or TCP.
- blacklisting_disabled
- If set to true, prevents a server to be black-listed on a query in case
there is no answer OR rcode is REFUSED.
- string()
- Returns a string representation of the object. Normally this is just the
name and IP address separated by a slash.
- compare($other)
- Used for overloading comparison operators.
- sum_time()
- Returns the total time spent sending queries and waiting for
responses.
- min_time()
- Returns the shortest time spent on a query.
- max_time()
- Returns the longest time spent on a query.
- average_time()
- Returns the average time spent on queries.
- median_time()
- Returns the median query time.
- stddev_time()
- Returns the standard deviation for the whole set of query times.
- add_fake_delegation($domain,$data)
- Adds fake delegation information to this specific nameserver object. Takes
the same arguments as the similarly named method in Zonemaster::Engine.
This is primarily used for internal information, and using it directly
will likely give confusing results (but may be useful to model certain
kinds of misconfigurations).
- add_fake_ds($domain,
$data)
- Adds fake DS information to this nameserver object. Takes the same
arguments as the similarly named method in Zonemaster::Engine.
- axfr( $domain, $callback,
$class )
- Does an AXFR for the requested domain from the nameserver. The callback
function will be called once for each received RR, with that RR as its
only argument. To continue getting more RRs, the callback must return a
true value. If it returns a true value, the AXFR will be aborted. See
Zonemaster::LDNS::axfr for more details.