dnspython is a DNS toolkit for Python. It supports almost all record types. It can be used for queries, zone transfers, and dynamic updates. It supports TSIG authenticated messages and EDNS0.
dnspython provides both high and low level access to DNS. The high level classes perform queries for data of a given name, type, and class, and return an answer set. The low level classes allow direct manipulation of DNS zones, messages, names, and records.
To see a few of the ways dnspython can be used, look in the examples/ directory.
dnspython is a utility to work with DNS, /etc/hosts
is thus not used. For
simple forward DNS lookups, better use socket.gethostbyname()
.
dnspython originated at Nominum where it was developed to facilitate the testing of DNS software. Nominum has generously allowed it to be open sourced under a BSD-style license, and helps support its future development by continuing to employ the author :).
- Many distributions have dnspython packaged for you, so you should check there first.
- If you have pip installed, you can do
pip install dnspython
- If not just download the source file and unzip it, then run
sudo python setup.py install
This is dnspython 1.15.0
-
IDNA 2008 support is now available if the "idna" module has been installed and IDNA 2008 is requested. The default IDNA behavior is still IDNA 2003. The new IDNA codec mechanism is currently only useful for direct calls to dns.name.from_text() or dns.name.from_unicode(), but in future releases it will be deployed throughout dnspython, e.g. so that you can read a masterfile with an IDNA 2008 codec in force.
-
By default, dns.name.to_unicode() is not strict about which version of IDNA the input complies with. Strictness can be requested by using one of the strict IDNA codecs.
-
The AVC RR is now supported.
-
Some problems with newlines in various output modes have been addressed.
-
dns.name.to_text() now returns text and not bytes on Python 3.x
-
Miscellaneous fixes for the Python 2/3 codeline merge.
-
Many "lint" fixes after the addition of pylint support.
-
The random number generator reseeds after a fork().
Python 2.6 or later.
For the latest in releases, documentation, and information, visit the dnspython home page at http://www.dnspython.org/
Bug reports may be opened at https://github.com/rthalley/dnspython/issues or sent to bugs@dnspython.org
A number of mailing lists are available. Visit the dnspython home page to subscribe or unsubscribe.
-
CSYNC RRs are now supported.
-
dns/message.py
(make_query
): Setting any value which implies EDNS will turn on EDNS ifuse_edns
has not been specified.
-
TSIG signature algorithm setting was broken by the Python 2 and Python 3 code line merge.
-
A bug in the LOC RR destroyed N/S and E/W distinctions within a degree of the equator or prime merdian respectively.
-
Misc. fixes to deal with fallout from the Python 2 & 3 merge. Fixes #156, #157, #158, #159, #160.
-
Running with python optimization on caused issues when stripped docstrings were referenced. Fixes #154
-
dns.zone.from_text()
erroneously required the zone to be provided. Fixes #153
-
Dnspython now uses a single source for Python 2 and Python 3, eliminating the painful merging between the Python 2 and Python 3 branches. Thank you so much to Arthur Gautier for taking on this challenge and making it work! It was a big job!
-
Support for Python older than 2.6 dropped.
-
Support for Python older than 3.3 dropped.
-
Zone origin can be specified as a string.
-
A rich string representation for all DNSExceptions.
-
setuptools has replaced distutils
-
Added support for CAA, CDS, CDNSKEY, EUI48, EUI64, and URI RR types.
-
Names now support the pickle protocol.
-
Ports can be specified per-nameserver in the stub resolver.
-
A number of Unicode name bugs have been fixed.
-
resolv.conf
processing now rejects lines with too few tokens. -
NameDicts now keep the max-depth value correct, and update properly.
-
Added
dns.zone.to_text()
. -
Added support for "options rotate" in
/etc/resolv.conf
. -
dns.rdtypes.ANY.DNSKEY
now has helpers functions to convert between the numeric form of the flags and a set of human-friendly strings -
The reverse name of an IPv6 mapped IPv4 address is now in the IPv4 reverse namespace.
-
The test system can now run the tests without requiring dnspython to be installed.
-
Preliminary Elliptic Curve DNSSEC Validation (requires ecdsa module)
-
dnspython raised an exception when reading a masterfile starting with leading whitespace
-
dnspython was affected by a python slicing API bug present on 64-bit windows.
-
Unicode escaping was applied at the wrong time.
-
RRSIG
to_text()
did not respect the relativize setting. -
APL RRs with zero rdlength were rejected.
-
The tokenizer could put back an unescaped token.
-
Making a response to a message signed with TSIG was broken.
-
The IXFR state machine didn't handle long IXFR diffs.
- Nothing
-
dns.resolver.Resolver
erroneously referred toretry_servfail
instead ofself.retry_servfail
. -
dns.tsigkeyring.to_text()
would fail trying to convert the keyname to text. -
Multi-message TSIGs were broken for algorithms other than HMAC-MD5 because we weren't passing the right digest module to the HMAC code.
-
dns.dnssec._find_candidate_keys()
tried to extract the key from the wrong variable name. -
$GENERATE tests were not backward compatible with python 2.4.
-
$GENERATE support
-
TLSA RR support
-
Added set_flags() method to dns.resolver.Resolver
-
Names with offsets >= 2^14 are no longer added to the compression table.
-
The "::" syntax is not used to shorten a single 16-bit section of the text form an IPv6 address.
-
Caches are now locked.
-
YXDOMAIN is raised if seen by the resolver.
-
Empty rdatasets are not printed.
-
DNSKEY key tags are no longer assumed to be unique.
-
Added dns.resolver.LRUCache. In this cache implementation, the cache size is limited to a user-specified number of nodes, and when adding a new node to a full cache the least-recently used node is removed. If you're crawling the web or otherwise doing lots of resolutions and you are using a cache, switching to the LRUCache is recommended.
-
dns.resolver.query()
will try TCP if a UDP response is truncated. -
The python socket module's DNS methods can be now be overridden with implementations that use dnspython's resolver.
-
Old DNSSEC types KEY, NXT, and SIG have been removed.
-
Whitespace is allowed in SSHFP fingerprints.
-
Origin checking in
dns.zone.from_xfr()
can be disabled. -
Trailing junk checking can be disabled.
-
A source port can be specified when creating a resolver query.
-
All EDNS values may now be specified to
dns.message.make_query()
.
-
IPv4 and IPv6 address processing is now stricter.
-
Bounds checking of slices in rdata wire processing is now more strict, and bounds errors (e.g. we got less data than was expected) now raise
dns.exception.FormError
rather thanIndexError
. -
Specifying a source port without specifying source used to have no effect, but now uses the wildcard address and the specified port.
- Nothing.
-
The rdata
_wire_cmp()
routine now handles relative names. -
The SIG RR implementation was missing
import struct
.
-
A boolean parameter,
raise_on_no_answer
, has been added to thequery()
methods. In no-error, no-data situations, this parameter determines whetherNoAnswer
should be raised or not. If True,NoAnswer
is raised. If False, then anAnswer()
object with a None rrset will be returned. -
Resolver
Answer()
objects now have a canonical_name field. -
Rdata now has a
__hash__
method.
-
Dnspython was erroneously doing case-insensitive comparisons of the names in NSEC and RRSIG RRs.
-
We now use
is
and not==
when testing what section an RR is in. -
The resolver now disallows metaqueries.
- Nothing.
- The
dns.dnssec
module didn't work at all due to missing imports that escaped detection in testing because the test suite also did the imports. The third time is the charm!
- Nothing.
- The
dns.dnssec
module didn't work with DSA due to namespace contamination from a "from"-style import.
-
dnspython now uses
poll()
instead ofselect()
when available. -
Basic DNSSEC validation can be done using
dns.dnsec.validate()
anddns.dnssec.validate_rrsig()
if you have PyCrypto 2.3 or later installed. Complete secure resolution is not yet available. -
Added
key_id()
to the DNSSEC module, which computes the DNSSEC key id of a DNSKEY rdata. -
Added
make_ds()
to the DNSSEC module, which returns the DS RR for a given DNSKEY rdata. -
dnspython now raises an exception if HMAC-SHA284 or HMAC-SHA512 are used with a Python older than 2.5.2. (Older Pythons do not compute the correct value.)
-
Symbolic constants are now available for TSIG algorithm names.
-
dns.resolver.zone_for_name()
didn't handle a query response with a CNAME or DNAME correctly in some cases. -
When specifying rdata types and classes as text, Unicode strings may now be used.
-
Hashlib compatibility issues have been fixed.
-
dns.message
now importsdns.edns
. -
The TSIG algorithm value was passed incorrectly to
use_tsig()
in some cases.
-
Support for hmac-sha1, hmac-sha224, hmac-sha256, hmac-sha384 and hmac-sha512 has been contributed by Kevin Chen.
-
The tokenizer's tokens are now Token objects instead of (type, value) tuples.
-
Escapes in masterfiles now work correctly. Previously they were only working correctly when the text involved was part of a domain name.
-
When constructing a DDNS update, if the
present()
method was used with a single rdata, a zero TTL was not added. -
The entropy pool needed locking to be thread safe.
-
The entropy pool's reading of
/dev/random
could cause dnspython to block. -
The entropy pool did buffered reads, potentially consuming more randomness than we needed.
-
The entropy pool did not seed with high quality randomness on Windows.
-
SRV records were compared incorrectly.
-
In the e164 query function, the resolver parameter was not used.
- Nothing
-
The 1.7.0 kitting process inadvertently omitted the code for the DLV RR.
-
Negative DDNS prerequisites are now handled correctly.
-
Rdatas now have a
to_digestable()
method, which returns the DNSSEC canonical form of the rdata, suitable for use in signature computations. -
The NSEC3, NSEC3PARAM, DLV, and HIP RR types are now supported.
-
An entropy module has been added and is used to randomize query ids.
-
EDNS0 options are now supported.
-
UDP IXFR is now supported.
-
The wire format parser now has a
one_rr_per_rrset
mode, which suppresses the usual coalescing of all RRs of a given type into a single RRset. -
Various helpful DNSSEC-related constants are now defined.
-
The resolver's
query()
method now has an optionalsource
parameter, allowing the source IP address to be specified.
-
On Windows, the resolver set the domain incorrectly.
-
DS RR parsing only allowed one Base64 chunk.
-
TSIG validation didn't always use absolute names.
-
NSEC.to_text()
only printed the last window. -
We did not canonicalize IPv6 addresses before comparing them; we would thus treat equivalent but different textual forms, e.g. "1:00::1" and "1::1" as being non-equivalent.
-
If the peer set a TSIG error, we didn't raise an exception.
-
Some EDNS bugs in the message code have been fixed (see the ChangeLog for details).
- Added dns.inet.is_multicast().
-
If
select()
raises an exception due to EINTR, we should justselect()
again. -
If the queried address is a multicast address, then don't check that the address of the response is the same as the address queried.
-
NAPTR comparisons didn't compare the preference field due to a typo.
-
Testing of whether a Windows NIC is enabled now works on Vista thanks to code contributed by Paul Marks.
-
Answer objects now support more of the python sequence protocol, forwarding the requests to the answer rrset. E.g.
for a in answer
is equivalent tofor a in answer.rrset
,answer[i]
is equivalent toanswer.rrset[i]
, andanswer[i:j]
is equivalent toanswer.rrset[i:j]
. -
Making requests using EDNS, including indicating DNSSEC awareness, is now easier. For example, you can now say:
q = dns.message.make_query('www.dnspython.org', 'MX', want_dnssec=True)
-
dns.query.xfr()
can now be used for IXFR. -
Support has been added for the DHCID, IPSECKEY, and SPF RR types.
-
UDP messages from unexpected sources can now be ignored by setting
ignore_unexpected
to True when callingdns.query.udp
.
-
If
/etc/resolv.conf
didn't exist, we raised an exception instead of simply using the default resolver configuration. -
In
dns.resolver.Resolver._config_win32_fromkey()
, we were passing the wrong variable toself._config_win32_search()
.
-
You can now convert E.164 numbers to/from their ENUM name forms:
>>> import dns.e164 >>> n = dns.e164.from_e164("+1 555 1212") >>> n <DNS name 2.1.2.1.5.5.5.1.e164.arpa.> >>> dns.e164.to_e164(n) '+15551212'
-
You can now convert IPv4 and IPv6 address to/from their corresponding DNS reverse map names:
>>> import dns.reversename >>> n = dns.reversename.from_address("127.0.0.1") >>> n <DNS name 1.0.0.127.in-addr.arpa.> >>> dns.reversename.to_address(n) '127.0.0.1'
-
You can now convert between Unicode strings and their IDN ACE form:
>>> n = dns.name.from_text(u'les-\u00e9l\u00e8ves.example.') >>> n <DNS name xn--les-lves-50ai.example.> >>> n.to_unicode() u'les-\xe9l\xe8ves.example.'
-
The origin parameter to
dns.zone.from_text()
anddns.zone.to_text()
is now optional. If not specified, the origin will be taken from the first $ORIGIN statement in the master file. -
Sanity checking of a zone can be disabled; this is useful when working with files which are zone fragments.
-
The correct delimiter was not used when retrieving the list of nameservers from the registry in certain versions of windows.
-
The floating-point version of latitude and longitude in LOC RRs (
float_latitude
andfloat_longitude
) had incorrect signs for south latitudes and west longitudes. -
BIND 8 TTL syntax is now accepted in all TTL-like places (i.e. SOA fields refresh, retry, expire, and minimum; SIG/RRSIG field original_ttl).
-
TTLs are now bounds checked when their text form is parsed, and their values must be in the closed interval
[0, 2^31 - 1]
.
-
In the resolver, if time goes backward a little bit, ignore it.
-
zone_for_name()
has been added to the resolver module. It returns the zone which is authoritative for the specified name, which is handy for dynamic update. E.g.import dns.resolver print dns.resolver.zone_for_name('www.dnspython.org')
will output
"dnspython.org."
andprint dns.resolver.zone_for_name('a.b.c.d.e.f.example.')
will output"."
. -
The default resolver can be fetched with the
get_default_resolver()
method. -
You can now get the parent (immediate superdomain) of a name by using the
parent()
method. -
Zone.iterate_rdatasets()
andZone.iterate_rdatas()
now have a default rdtype ofdns.rdatatype.ANY
like the documentation says. -
A Dynamic DNS example, ddns.py, has been added.
-
The source address and port may now be specified when calling
dns.query.{udp,tcp,xfr}
. -
The resolver now does exponential backoff each time it runs through all of the nameservers.
-
Rcodes which indicate a nameserver is likely to be a "permanent failure" for a query cause the nameserver to be removed from the mix for that query.
-
dns.message.Message.find_rrset()
now uses an index, vastly improving thefrom_wire()
performance of large messages such as zone transfers. -
Added
dns.message.make_response()
, which creates a skeletal response for the specified query. -
Added
opcode()
andset_opcode()
convenience methods to thedns.message.Message
class. Added therequest_payload
attribute to the Message class. -
The
file
parameter ofdns.name.Name.to_wire()
is now optional; if omitted, the wire form will be returned as the value of the function. -
dns.zone.from_xfr()
in relativization mode incorrectly setzone.origin
to the empty name. -
The masterfile parser incorrectly rejected TXT records where a value was not quoted.
-
The NSEC format doesn't allow specifying types by number, so we shouldn't either. (Using the unknown type format is still OK though.)
-
The resolver wasn't catching
dns.exception.Timeout
, so a timeout erroneously caused the whole resolution to fail instead of just going on to the next server. -
The renderer module didn't import random, causing an exception to be raised if a query id wasn't provided when a Renderer was created.
-
The conversion of LOC milliseconds values from text to binary was incorrect if the length of the milliseconds string was not 3.
- Added support for the SSHFP type.
-
Added support for new DNSSEC types RRSIG, NSEC, and DNSKEY.
-
This release fixes all known bugs.
-
See the ChangeLog file for more detailed information on changes since the prior release.