NAME¶

Zonemaster::Engine::Nameserver - object representing a DNS nameserver

SYNOPSIS¶

    my $ns = Zonemaster::Engine::Nameserver->new({ name => 'ns.nic.se', address => '212.247.7.228' });
    my $p = $ns->query('www.iis.se', 'AAAA');

DESCRIPTION¶

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.

ATTRIBUTES¶

name

A Zonemaster::Engine::DNSName object holding the nameserver's name.

address

A Net::IP::XS 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.

times

A reference to a list with elapsed time values for the queries made through this nameserver.

CLASS METHODS¶

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.

INSTANCE METHODS¶

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 'class' and 'edns_details' directly correspond to methods in the Zonemaster::LDNS::Resolver object.

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.

source_address()

    my $src_address = source_address();
    

Returns the configured IPv4 or IPv6 source address to be used by the underlying DNS resolver for sending queries, or "undef" if the source address is the empty string.

empty_cache()

Clears the caches of Zonemaster::Engine::Nameserver (name server names and IP addresses) and Zonemaster::Engine::Nameserver::Cache (query and response packets) objects.