/usr/lib/python2.7/dist-packages/ldnsx.py is in python-ldns 1.7.0-3ubuntu4.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 | # Copyright (C) Xelerance Corp. <http://www.xelerance.com/>.
# Author: Christopher Olah <colah@xelerance.com>
# License: BSD
""" Easy DNS (including DNSSEC) via ldns.
ldns is a great library. It is a powerfull tool for
working with DNS. python-ldns it is a straight up clone of the C
interface, howver that is not a very good interface for python. Its
documentation is incomplete and some functions don't work as
described. And some objects don't have a full python API.
ldnsx aims to fix this. It wraps around the ldns python bindings,
working around its limitations and providing a well-documented, more
pythonistic interface.
**WARNING:**
**API subject to change.** No backwards compatibility guarantee. Write software using this version at your own risk!
Examples
--------
Query the default resolver for google.com's A records. Print the response
packet.
>>> import ldnsx
>>> resolver = ldnsx.resolver()
>>> print resolver.query("google.com","A")
Print the root NS records from f.root-servers.net; if we get a
response, else an error message.
>>> import ldnsx
>>> pkt = ldnsx.resolver("f.root-servers.net").query(".", "NS")
>>> if pkt:
>>> for rr in pkt.answer():
>>> print rr
>>> else:
>>> print "response not received"
"""
import time, sys, calendar, warnings, socket
try:
import ldns
except ImportError:
print >> sys.stderr, "ldnsx requires the ldns-python sub-package from http://www.nlnetlabs.nl/projects/ldns/"
print >> sys.stderr, "Fedora/CentOS: yum install ldns-python"
print >> sys.stderr, "Debian/Ubuntu: apt-get install python-ldns"
print >> sys.stderr, "openSUSE: zypper in python-ldns"
sys.exit(1)
__version__ = "0.1"
def isValidIP(ipaddr):
try:
v4 = socket.inet_pton(socket.AF_INET,ipaddr)
return 4
except:
try:
v6 = socket.inet_pton(socket.AF_INET6,ipaddr)
return 6
except:
return 0
def query(name, rr_type, rr_class="IN", flags=["RD"], tries = 3, res=None):
"""Convenience function. Creates a resolver and then queries it. Refer to resolver.query()
* name -- domain to query for
* rr_type -- rr_type to query for
* flags -- flags for query (list of strings)
* tries -- number of times to retry the query on failure
* res -- configurations for the resolver as a dict -- see resolver()
"""
if isinstance(res, list) or isinstance(res, tuple):
res = resolver(*res)
elif isinstance(res, dict):
res = resolver(**res)
else:
res = resolver(res)
return res.query(name, rr_type, rr_class, flags, tries)
def get_rrs(name, rr_type, rr_class="IN", tries = 3, strict = False, res=None, **kwds):
"""Convenience function. Gets RRs for name of type rr_type trying tries times.
If strict, it raises and exception on failure, otherwise it returns [].
* name -- domain to query for
* rr_type -- rr_type to query for
* flags -- flags for query (list of strings)
* tries -- number of times to retry the query on failure
* strict -- if the query fails, do we return [] or raise an exception?
* res -- configurations for the resolver as a dict -- see resolver()
* kwds -- query filters, refer to packet.answer()
"""
if isinstance(res, list) or isinstance(res, tuple):
res = resolver(*res)
elif isinstance(res, dict):
res = resolver(**res)
else:
res = resolver(res)
if "|" in rr_type:
pkt = res.query(name, "ANY", rr_class=rr_class, tries=tries)
else:
pkt = res.query(name, rr_type, rr_class=rr_class, tries=tries)
if pkt:
if rr_type in ["", "ANY", "*"]:
return pkt.answer( **kwds)
else:
return pkt.answer(rr_type=rr_type, **kwds)
else:
if strict:
raise Exception("LDNS couldn't complete query")
else:
return []
def secure_query(name, rr_type, rr_class="IN", flags=["RD"], tries = 1, flex=False, res=None):
"""Convenience function. Creates a resolver and then does a DNSSEC query. Refer to resolver.query()
* name -- domain to query for
* rr_type -- rr_type to query for
* flags -- flags for query (list of strings)
* tries -- number of times to retry the query on failure
* flex -- if we can't verify data, exception or warning?
* res -- configurations for the resolver as a dict -- see resolver()"""
if isinstance(res, list) or isinstance(res, tuple):
res = resolver(*res)
elif isinstance(res, dict):
res = resolver(**res)
else:
res = resolver(res)
pkt = res.query(name, rr_type, rr_class, flags, tries)
if pkt.rcode() == "SERVFAIL":
raise Exception("%s lookup failed (server error or dnssec validation failed)" % name)
if pkt.rcode() == "NXDOMAIN":
if "AD" in pkt.flags():
raise Exception("%s lookup failed (non-existence proven by DNSSEC)" % name )
else:
raise Exception("%s lookup failed" % name )
if pkt.rcode() == "NOERROR":
if "AD" not in pkt.flags():
if not flex:
raise Exception("DNS lookup was insecure")
else:
warnings.warn("DNS lookup was insecure")
return pkt
else:
raise Exception("unknown ldns error, %s" % pkt.rcode())
class resolver:
""" A wrapper around ldns.ldns_resolver.
**Examples**
Making resolvers is easy!
>>> from ldnsx import resolver
>>> resolver() # from /etc/resolv.conf
<resolver: 192.168.111.9>
>>> resolver("") # resolver with no nameservers
<resolver: >
>>> resolver("193.110.157.135") #resolver pointing to ip addr
<resolver: 193.110.157.135>
>>> resolver("f.root-servers.net") # resolver pointing ip address(es) resolved from name
<resolver: 2001:500:2f::f, 192.5.5.241>
>>> resolver("193.110.157.135, 193.110.157.136")
>>> # resolver pointing to multiple ip addr, first takes precedence.
<resolver: 193.110.157.136, 193.110.157.135>
So is playing around with their nameservers!
>>> import ldnsx
>>> res = ldnsx.resolver("192.168.1.1")
>>> res.add_nameserver("192.168.1.2")
>>> res.add_nameserver("192.168.1.3")
>>> res.nameservers_ip()
["192.168.1.1","192.168.1.2","192.168.1.3"]
And querying!
>>> from ldnsx import resolver
>>> res= resolver()
>>> res.query("cow.com","A")
;; ->>HEADER<<- opcode: QUERY, rcode: NOERROR, id: 7663
;; flags: qr rd ra ; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0
;; QUESTION SECTION:
;; cow.com. IN A
;; ANSWER SECTION:
cow.com. 300 IN A 208.87.34.18
;; AUTHORITY SECTION:
;; ADDITIONAL SECTION:
;; Query time: 313 msec
;; SERVER: 192.168.111.9
;; WHEN: Fri Jun 3 11:01:02 2011
;; MSG SIZE rcvd: 41
"""
def __init__(self, ns = None, dnssec = False, tcp = False, port = 53):
"""resolver constructor
* ns -- the nameserver/comma delimited nameserver list
defaults to settings from /etc/resolv.conf
* dnssec -- should the resolver try and use dnssec or not?
* tcp -- should the resolver use TCP
'auto' is a depricated work around for old ldns problems
* port -- the port to use, must be the same for all nameservers
"""
# We construct based on a file and dump the nameservers rather than using
# ldns_resolver_new() to avoid environment/configuration/magic specific
# bugs.
self._ldns_resolver = ldns.ldns_resolver.new_frm_file("/etc/resolv.conf")
if ns != None:
self.drop_nameservers()
nm_list = ns.split(',')
nm_list = map(lambda s: s.strip(), nm_list)
nm_list = filter(lambda s: s != "", nm_list)
nm_list.reverse()
for nm in nm_list:
self.add_nameserver(nm)
# Configure DNSSEC, tcp and port
self.set_dnssec(dnssec)
if tcp == 'auto':
self.autotcp = True
self._ldns_resolver.set_usevc(False)
else:
self.autotcp = False
self._ldns_resolver.set_usevc(tcp)
self._ldns_resolver.set_port(port)
def query(self, name, rr_type, rr_class="IN", flags=["RD"], tries = 3):
"""Run a query on the resolver.
* name -- name to query for
* rr_type -- the record type to query for
* rr_class -- the class to query for, defaults to IN (Internet)
* flags -- the flags to send the query with
* tries -- the number of times to attempt to acheive query in case of packet loss, etc
**Examples**
Let's get some A records!
>>> google_a_records = resolver.query("google.com","A").answer()
Using DNSSEC is easy :)
>>> dnssec_pkt = ldnsx.resolver(dnssec=True).query("xelerance.com")
We let you use strings to make things easy, but if you prefer stay close to DNS...
>>> AAAA = 28
>>> resolver.query("ipv6.google.com", AAAA)
**More about rr_type**
rr_type must be a supported resource record type. There are a large number of RR types:
=========== =================================== ==================
TYPE Value and meaning Reference
=========== =================================== ==================
A 1 a host address [RFC1035]
NS 2 an authoritative name server [RFC1035]
...
AAAA 28 IP6 Address [RFC3596]
...
DS 43 Delegation Signer [RFC4034][RFC3658]
...
DNSKEY 48 DNSKEY [RFC4034][RFC3755]
...
Unassigned 32770-65279
Private use 65280-65534
Reserved 65535
=========== =================================== ==================
(From http://www.iana.org/assignments/dns-parameters)
RR types are given as a string (eg. "A"). In the case of Unassigned/Private use/Reserved ones,
they are given as "TYPEXXXXX" where XXXXX is the number. ie. RR type 65280 is "TYPE65280". You
may also pass the integer, but you always be given the string.
If the version of ldnsx you are using is old, it is possible that there could be new rr_types that
we don't recognise mnemonic for. You can still use the number XXX or the string "TYPEXXX". To
determine what rr_type menmonics we support, please refer to resolver.supported_rr_types()
"""
# Determine rr_type int
if rr_type in _rr_types.keys():
_rr_type = _rr_types[rr_type]
elif isinstance(rr_type,int):
_rr_type = rr_type
elif isinstance(rr_type,str) and rr_type[0:4] == "TYPE":
try:
_rr_type = int(rr_type[4:])
except:
raise Exception("%s is a bad RR type. TYPEXXXX: XXXX must be a number")
else:
raise Exception("ldnsx (version %s) does not support the RR type %s." % (__version__, str(rr_type)) )
# Determine rr_class int
if rr_class == "IN": _rr_class = ldns.LDNS_RR_CLASS_IN
elif rr_class == "CH": _rr_class = ldns.LDNS_RR_CLASS_CH
elif rr_class == "HS": _rr_class = ldns.LDNS_RR_CLASS_HS
else:
raise Exception("ldnsx (version %s) does not support the RR class %s." % (__version__, str(rr_class)) )
# Determine flags int
_flags = 0
if "QR" in flags: _flags |= ldns.LDNS_QR
if "AA" in flags: _flags |= ldns.LDNS_AA
if "TC" in flags: _flags |= ldns.LDNS_TC
if "RD" in flags: _flags |= ldns.LDNS_RD
if "CD" in flags: _flags |= ldns.LDNS_CD
if "RA" in flags: _flags |= ldns.LDNS_RA
if "AD" in flags: _flags |= ldns.LDNS_AD
# Query
if tries == 0: return None
try:
pkt = self._ldns_resolver.query(name, _rr_type, _rr_class, _flags)
except KeyboardInterrupt: #Since so much time is spent waiting on ldns, this is very common place for Ctr-C to fall
raise
except: #Since the ldns exceptiion is not very descriptive...
raise Exception("ldns backend ran into problems. Likely, the name you were querying for, %s, was invalid." % name)
#Deal with failed queries
if not pkt:
if tries <= 1:
return None
else:
# One of the major causes of none-packets is truncation of packets
# When autotcp is set, we are in a flexible enough position to try and use tcp
# to get around this.
# Either way, we want to replace the resolver, since resolvers will sometimes
# just freeze up.
if self.autotcp:
self = resolver( ",".join(self.nameservers_ip()),tcp=True, dnssec = self._ldns_resolver.dnssec())
self.autotcp = True
pkt = self.query(name, rr_type, rr_class=rr_class, flags=flags, tries = tries-1)
self._ldns_resolver.set_usevc(False)
return pkt
else:
self = resolver( ",".join(self.nameservers_ip()), tcp = self._ldns_resolver.usevc(), dnssec = self._ldns_resolver.dnssec() )
time.sleep(1) # It could be that things are failing because of a brief outage
return self.query(name, rr_type, rr_class=rr_class, flags=flags, tries = tries-1)
elif self.autotcp:
pkt = packet(pkt)
if "TC" in pkt.flags():
self._ldns_resolver.set_usevc(True)
pkt2 = self.query(name, rr_type, rr_class=rr_class, flags=flags, tries = tries-1)
self._ldns_resolver.set_usevc(False)
if pkt2: return packet(pkt2)
return pkt
return packet(pkt)
#ret = []
#for rr in pkt.answer().rrs():
# ret.append([str(rr.owner()),rr.ttl(),rr.get_class_str(),rr.get_type_str()]+[str(rdf) for rdf in rr.rdfs()])
#return ret
def suported_rr_types(self):
""" Returns the supported DNS resource record types.
Refer to resolver.query() for thorough documentation of resource
record types or refer to:
http://www.iana.org/assignments/dns-parameters
"""
return _rr_types.keys()
def AXFR(self,name):
"""AXFR for name
* name -- name to AXFR for
This function is a generator. As it AXFRs it will yield you the records.
**Example**
Let's get a list of the tlds (gotta catch em all!):
>>> tlds = []
>>> for rr in resolver("f.root-servers.net").AXFR("."):
>>> if rr.rr_type() == "NS":
>>> tlds.append(rr.owner())
"""
#Dname seems to be unecessary on some computers, but it is on others. Avoid bugs.
if self._ldns_resolver.axfr_start(ldns.ldns_dname(name), ldns.LDNS_RR_CLASS_IN) != ldns.LDNS_STATUS_OK:
raise Exception("Starting AXFR failed. Error: %s" % ldns.ldns_get_errorstr_by_id(status))
pres = self._ldns_resolver.axfr_next()
while pres:
yield resource_record(pres)
pres = self._ldns_resolver.axfr_next()
def nameservers_ip(self):
""" returns a list of the resolvers nameservers (as IP addr)
"""
nm_stack2 =[]
nm_str_stack2=[]
nm = self._ldns_resolver.pop_nameserver()
while nm:
nm_stack2.append(nm)
nm_str_stack2.append(str(nm))
nm = self._ldns_resolver.pop_nameserver()
for nm in nm_stack2:
self._ldns_resolver.push_nameserver(nm)
nm_str_stack2.reverse()
return nm_str_stack2
def add_nameserver(self,ns):
""" Add a nameserver, IPv4/IPv6/name.
"""
if isValidIP(ns) == 4:
address = ldns.ldns_rdf_new_frm_str(ldns.LDNS_RDF_TYPE_A,ns)
self._ldns_resolver.push_nameserver(address)
elif isValidIP(ns) == 6:
address = ldns.ldns_rdf_new_frm_str(ldns.LDNS_RDF_TYPE_AAAA,ns)
self._ldns_resolver.push_nameserver(address)
else:
resolver = ldns.ldns_resolver.new_frm_file("/etc/resolv.conf")
#address = resolver.get_addr_by_name(ns)
address = resolver.get_addr_by_name(ldns.ldns_dname(ns))
if not address:
address = resolver.get_addr_by_name(ldns.ldns_dname(ns))
if not address:
raise Exception("Failed to resolve address for %s" % ns)
for rr in address.rrs():
self._ldns_resolver.push_nameserver_rr(rr)
def drop_nameservers(self):
"""Drops all nameservers.
This function causes the resolver to forget all nameservers.
"""
while self._ldns_resolver.pop_nameserver():
pass
def set_nameservers(self, nm_list):
"""Takes a list of nameservers and sets the resolver to use them
"""
self.drop_nameservers()
for nm in nm_list:
self.add_nameserver(nm)
def __repr__(self):
return "<resolver: %s>" % ", ".join(self.nameservers_ip())
__str__ = __repr__
def set_dnssec(self,new_dnssec_status):
"""Set whether the resolver uses DNSSEC.
"""
self._ldns_resolver.set_dnssec(new_dnssec_status)
class packet:
def _construct_rr_filter(self, **kwds):
def match(pattern, target):
if pattern[0] in ["<",">","!"]:
rel = pattern[0]
pattern=pattern[1:]
elif pattern[0:2] in ["<=","=>"]:
rel = pattern[0:2]
pattern=pattern[2:]
else:
rel = "="
for val in pattern.split("|"):
if {"<" : target < val,
">" : target > val,
"!" : target != val,
"=" : target == val,
">=": target >= val,
"<=": target <= val}[rel]:
return True
return False
def f(rr):
for key in kwds.keys():
if ( ( isinstance(kwds[key], list) and str(rr[key]) not in map(str,kwds[key]) )
or ( not isinstance(kwds[key], list) and not match(str(kwds[key]), str(rr[key])))):
return False
return True
return f
def __init__(self, pkt):
self._ldns_pkt = pkt
def __repr__(self):
return str(self._ldns_pkt)
__str__ = __repr__
def rcode(self):
"""Returns the rcode.
Example returned value: "NOERROR"
possilbe rcodes (via ldns): "FORMERR", "MASK", "NOERROR",
"NOTAUTH", "NOTIMPL", "NOTZONE", "NXDOMAIN",
"NXRSET", "REFUSED", "SERVFAIL", "SHIFT",
"YXDOMAIN", "YXRRSET"
Refer to http://www.iana.org/assignments/dns-parameters
section: DNS RCODEs
"""
return self._ldns_pkt.rcode2str()
def opcode(self):
"""Returns the rcode.
Example returned value: "QUERY"
"""
return self._ldns_pkt.opcode2str()
def flags(self):
"""Return packet flags (as list of strings).
Example returned value: ['QR', 'RA', 'RD']
**What are the flags?**
======== ==== ===================== =========
Bit Flag Description Reference
======== ==== ===================== =========
bit 5 AA Authoritative Answer [RFC1035]
bit 6 TC Truncated Response [RFC1035]
bit 7 RD Recursion Desired [RFC1035]
bit 8 RA Recursion Allowed [RFC1035]
bit 9 Reserved
bit 10 AD Authentic Data [RFC4035]
bit 11 CD Checking Disabled [RFC4035]
======== ==== ===================== =========
(from http://www.iana.org/assignments/dns-parameters)
There is also QR. It is mentioned in other sources,
though not the above page. It being false means that
the packet is a query, it being true means that it is
a response.
"""
ret = []
if self._ldns_pkt.aa(): ret += ["AA"]
if self._ldns_pkt.ad(): ret += ["AD"]
if self._ldns_pkt.cd(): ret += ["CD"]
if self._ldns_pkt.qr(): ret += ["QR"]
if self._ldns_pkt.ra(): ret += ["RA"]
if self._ldns_pkt.rd(): ret += ["RD"]
if self._ldns_pkt.tc(): ret += ["TC"]
return ret
def answer(self, **filters):
"""Returns the answer section.
* filters -- a filtering mechanism
Since a very common desire is to filter the resource records in a packet
section, we provide a special tool for doing this: filters. They are a
lot like regular python filters, but more convenient. If you set a
field equal to some value, you will only receive resource records for which
it holds true.
**Examples**
>>> res = ldnsx.resolver()
>>> pkt = res.query("google.ca","A")
>>> pkt.answer()
[google.ca. 28 IN A 74.125.91.99
, google.ca. 28 IN A 74.125.91.105
, google.ca. 28 IN A 74.125.91.147
, google.ca. 28 IN A 74.125.91.103
, google.ca. 28 IN A 74.125.91.104
, google.ca. 28 IN A 74.125.91.106
]
To understand filters, consider the following:
>>> pkt = ldnsx.query("cow.com","ANY")
>>> pkt.answer()
[cow.com. 276 IN A 208.87.32.75
, cow.com. 3576 IN NS sell.internettraffic.com.
, cow.com. 3576 IN NS buy.internettraffic.com.
, cow.com. 3576 IN SOA buy.internettraffic.com. hostmaster.hostingnet.com. 1308785320 10800 3600 604800 3600
]
>>> pkt.answer(rr_type="A")
[cow.com. 276 IN A 208.87.32.75
]
>>> pkt.answer(rr_type="A|NS")
[cow.com. 276 IN A 208.87.32.75
, cow.com. 3576 IN NS sell.internettraffic.com.
, cow.com. 3576 IN NS buy.internettraffic.com.
]
>>> pkt.answer(rr_type="!NS")
[cow.com. 276 IN A 208.87.32.75
, cow.com. 3576 IN SOA buy.internettraffic.com. hostmaster.hostingnet.com. 1308785320 10800 3600 604800 3600
]
fields are the same as when indexing a resource record.
note: ordering is alphabetical.
"""
ret = [resource_record(rr) for rr in self._ldns_pkt.answer().rrs()]
return filter(self._construct_rr_filter(**filters), ret)
def authority(self, **filters):
"""Returns the authority section.
* filters -- a filtering mechanism
Since a very common desire is to filter the resource records in a packet
section, we provide a special tool for doing this: filters. They are a
lot like regular python filters, but more convenient. If you set a
field equal to some value, you will only receive resource records for which
it holds true. See answer() for details.
**Examples**
>>> res = ldnsx.resolver()
>>> pkt = res.query("google.ca","A")
>>> pkt.authority()
[google.ca. 251090 IN NS ns3.google.com.
, google.ca. 251090 IN NS ns1.google.com.
, google.ca. 251090 IN NS ns2.google.com.
, google.ca. 251090 IN NS ns4.google.com.
]
"""
ret = [resource_record(rr) for rr in self._ldns_pkt.authority().rrs()]
return filter(self._construct_rr_filter(**filters), ret)
def additional(self, **filters):
"""Returns the additional section.
* filters -- a filtering mechanism
Since a very common desire is to filter the resource records in a packet
section, we provide a special tool for doing this: filters. They are a
lot like regular python filters, but more convenient. If you set a
field equal to some value, you will only receive resource records for which
it holds true. See answer() for details.
**Examples**
>>> res = ldnsx.resolver()
>>> pkt = res.query("google.ca","A")
>>> pkt.additional()
[ns3.google.com. 268778 IN A 216.239.36.10
, ns1.google.com. 262925 IN A 216.239.32.10
, ns2.google.com. 255659 IN A 216.239.34.10
, ns4.google.com. 264489 IN A 216.239.38.10
]
"""
ret = [resource_record(rr) for rr in self._ldns_pkt.additional().rrs()]
return filter(self._construct_rr_filter(**filters), ret)
def question(self, **filters):
"""Returns the question section.
* filters -- a filtering mechanism
Since a very common desire is to filter the resource records in a packet
section, we provide a special tool for doing this: filters. They are a
lot like regular python filters, but more convenient. If you set a
field equal to some value, you will only receive resource records for which
it holds true. See answer() for details.
"""
ret = [resource_record(rr) for rr in self._ldns_pkt.question().rrs()]
return filter(self._construct_rr_filter(**filters), ret)
class resource_record:
_rdfs = None
_iter_pos = None
def __init__(self, rr):
self._ldns_rr = rr
self._rdfs = [str(rr.owner()),rr.ttl(),rr.get_class_str(),rr.get_type_str()]+[str(rdf) for rdf in rr.rdfs()]
def __repr__(self):
return str(self._ldns_rr)
__str__ = __repr__
def __iter__(self):
self._iter_pos = 0
return self
def next(self):
if self._iter_pos < len(self._rdfs):
self._iter_pos += 1
return self._rdfs[self._iter_pos-1]
else:
raise StopIteration
def __len__(self):
try:
return len(self._rdfs)
except:
return 0
def __getitem__(self, n):
if isinstance(n, int):
return self._rdfs[n]
elif isinstance(n, str):
n = n.lower()
if n in ["owner"]:
return self.owner()
elif n in ["rr_type", "rr type", "type"]:
return self.rr_type()
elif n in ["rr_class", "rr class", "class"]:
return self.rr_class()
elif n in ["covered_type", "covered type", "type2"]:
return self.covered_type()
elif n in ["ttl"]:
return self.ttl()
elif n in ["ip"]:
return self.ip()
elif n in ["alg", "algorithm"]:
return self.alg()
elif n in ["protocol"]:
return self.protocol()
elif n in ["flags"]:
return self.flags()
else:
raise Exception("ldnsx (version %s) does not recognize the rr field %s" % (__version__,n) )
else:
raise TypeError("bad type %s for index resource record" % type(n) )
#def rdfs(self):
# return self._rdfs.clone()
def owner(self):
"""Get the RR's owner"""
return str(self._ldns_rr.owner())
def rr_type(self):
"""Get a RR's type """
return self._ldns_rr.get_type_str()
def covered_type(self):
"""Get an RRSIG RR's covered type"""
if self.rr_type() == "RRSIG":
return self[4]
else:
return ""
def rr_class(self):
"""Get the RR's collapse"""
return self._ldns_rr.get_class_str()
def ttl(self):
"""Get the RR's TTL"""
return self._ldns_rr.ttl()
def inception(self, out_format="UTC"):
"""returns the inception time in format out_format, defaulting to a UTC string.
options for out_format are:
UTC -- a UTC string eg. 20110712192610 (2011/07/12 19:26:10)
unix -- number of seconds since the epoch, Jan 1, 1970
struct_time -- the format used by python's time library
"""
# Something very strange is going on with inception/expiration dates in DNS.
# According to RFC 4034 section 3.1.5 (http://tools.ietf.org/html/rfc4034#page-9)
# the inception/expiration fields should be in seconds since Jan 1, 1970, the Unix
# epoch (as is standard in unix). Yet all the packets I've seen provide UTC encoded
# as a string instead, eg. "20110712192610" which is 2011/07/12 19:26:10.
#
# It turns out that this is a standard thing that ldns is doing before the data gets
# to us.
if self.rr_type() == "RRSIG":
if out_format.lower() in ["utc", "utc str", "utc_str"]:
return self[9]
elif out_format.lower() in ["unix", "posix", "ctime"]:
return calendar.timegm(time.strptime(self[9], "%Y%m%d%H%M%S"))
elif out_format.lower() in ["relative"]:
return calendar.timegm(time.strptime(self[9], "%Y%m%d%H%M%S")) - time.time()
elif out_format.lower() in ["struct_time", "time.struct_time"]:
return time.strptime(self[9], "%Y%m%d%H%M%S")
else:
raise Exception("unrecognized time format")
else:
return ""
def expiration(self, out_format="UTC"):
"""get expiration time. see inception() for more information"""
if self.rr_type() == "RRSIG":
if out_format.lower() in ["utc", "utc str", "utc_str"]:
return self[8]
elif out_format.lower() in ["unix", "posix", "ctime"]:
return calendar.timegm(time.strptime(self[8], "%Y%m%d%H%M%S"))
elif out_format.lower() in ["relative"]:
return calendar.timegm(time.strptime(self[8], "%Y%m%d%H%M%S")) - time.time()
elif out_format.lower() in ["struct_time", "time.struct_time"]:
return time.strptime(self[8], "%Y%m%d%H%M%S")
else:
raise Exception("unrecognized time format")
else:
return ""
def ip(self):
""" IP address form A/AAAA record"""
if self.rr_type() in ["A", "AAAA"]:
return self[4]
else:
raise Exception("ldnsx does not support ip for records other than A/AAAA")
def alg(self):
"""Returns algorithm of RRSIG/DNSKEY/DS"""
t = self.rr_type()
if t == "RRSIG":
return int(self[5])
elif t == "DNSKEY":
return int(self[6])
elif t == "DS":
return int(self[5])
else:
return -1
def protocol(self):
""" Returns proticol of the DNSKEY"""
t = self.rr_type()
if t == "DNSKEY":
return int(self[5])
else:
return -1
def flags(self):
"""Return RR flags for DNSKEY """
t = self.rr_type()
if t == "DNSKEY":
ret = []
n = int(self[4])
for m in range(1):
if 2**(15-m) & n:
if m == 7: ret.append("ZONE")
elif m == 8: ret.append("REVOKE")
elif m ==15: ret.append("SEP")
else: ret.append(m)
return ret
else:
return []
_rr_types={
"A" : ldns.LDNS_RR_TYPE_A,
"A6" : ldns.LDNS_RR_TYPE_A6,
"AAAA" : ldns.LDNS_RR_TYPE_AAAA,
"AFSDB": ldns.LDNS_RR_TYPE_AFSDB,
"ANY" : ldns.LDNS_RR_TYPE_ANY,
"APL" : ldns.LDNS_RR_TYPE_APL,
"ATMA" : ldns.LDNS_RR_TYPE_ATMA,
"AXFR" : ldns.LDNS_RR_TYPE_AXFR,
"CDNSKEY" : ldns.LDNS_RR_TYPE_CDNSKEY,
"CDS" : ldns.LDNS_RR_TYPE_CDS,
"CERT" : ldns.LDNS_RR_TYPE_CERT,
"CNAME": ldns.LDNS_RR_TYPE_CNAME,
"COUNT": ldns.LDNS_RR_TYPE_COUNT,
"DHCID": ldns.LDNS_RR_TYPE_DHCID,
"DLV" : ldns.LDNS_RR_TYPE_DLV,
"DNAME": ldns.LDNS_RR_TYPE_DNAME,
"DNSKEY": ldns.LDNS_RR_TYPE_DNSKEY,
"DS" : ldns.LDNS_RR_TYPE_DS,
"EID" : ldns.LDNS_RR_TYPE_EID,
"FIRST": ldns.LDNS_RR_TYPE_FIRST,
"GID" : ldns.LDNS_RR_TYPE_GID,
"GPOS" : ldns.LDNS_RR_TYPE_GPOS,
"HINFO": ldns.LDNS_RR_TYPE_HINFO,
"IPSECKEY": ldns.LDNS_RR_TYPE_IPSECKEY,
"ISDN" : ldns.LDNS_RR_TYPE_ISDN,
"IXFR" : ldns.LDNS_RR_TYPE_IXFR,
"KEY" : ldns.LDNS_RR_TYPE_KEY,
"KX" : ldns.LDNS_RR_TYPE_KX,
"LAST" : ldns.LDNS_RR_TYPE_LAST,
"LOC" : ldns.LDNS_RR_TYPE_LOC,
"MAILA": ldns.LDNS_RR_TYPE_MAILA,
"MAILB": ldns.LDNS_RR_TYPE_MAILB,
"MB" : ldns.LDNS_RR_TYPE_MB,
"MD" : ldns.LDNS_RR_TYPE_MD,
"MF" : ldns.LDNS_RR_TYPE_MF,
"MG" : ldns.LDNS_RR_TYPE_MG,
"MINFO": ldns.LDNS_RR_TYPE_MINFO,
"MR" : ldns.LDNS_RR_TYPE_MR,
"MX" : ldns.LDNS_RR_TYPE_MX,
"NAPTR": ldns.LDNS_RR_TYPE_NAPTR,
"NIMLOC": ldns.LDNS_RR_TYPE_NIMLOC,
"NS" : ldns.LDNS_RR_TYPE_NS,
"NSAP" : ldns.LDNS_RR_TYPE_NSAP,
"NSAP_PTR" : ldns.LDNS_RR_TYPE_NSAP_PTR,
"NSEC" : ldns.LDNS_RR_TYPE_NSEC,
"NSEC3": ldns.LDNS_RR_TYPE_NSEC3,
"NSEC3PARAM" : ldns.LDNS_RR_TYPE_NSEC3PARAM,
"NSEC3PARAMS" : ldns.LDNS_RR_TYPE_NSEC3PARAMS,
"NULL" : ldns.LDNS_RR_TYPE_NULL,
"NXT" : ldns.LDNS_RR_TYPE_NXT,
"OPENPGPKEY" : ldns.LDNS_RR_TYPE_OPENPGPKEY,
"OPT" : ldns.LDNS_RR_TYPE_OPT,
"PTR" : ldns.LDNS_RR_TYPE_PTR,
"PX" : ldns.LDNS_RR_TYPE_PX,
"RP" : ldns.LDNS_RR_TYPE_RP,
"RRSIG": ldns.LDNS_RR_TYPE_RRSIG,
"RT" : ldns.LDNS_RR_TYPE_RT,
"SIG" : ldns.LDNS_RR_TYPE_SIG,
"SINK" : ldns.LDNS_RR_TYPE_SINK,
"SOA" : ldns.LDNS_RR_TYPE_SOA,
"SRV" : ldns.LDNS_RR_TYPE_SRV,
"SSHFP": ldns.LDNS_RR_TYPE_SSHFP,
"TLSA" : ldns.LDNS_RR_TYPE_TLSA,
"TSIG" : ldns.LDNS_RR_TYPE_TSIG,
"TXT" : ldns.LDNS_RR_TYPE_TXT,
"UID" : ldns.LDNS_RR_TYPE_UID,
"UINFO": ldns.LDNS_RR_TYPE_UINFO,
"UNSPEC": ldns.LDNS_RR_TYPE_UNSPEC,
"WKS" : ldns.LDNS_RR_TYPE_WKS,
"X25" : ldns.LDNS_RR_TYPE_X25
}
|