lib/dnspython/examples/reverse.py

   1 #!/usr/bin/env python
   2
   3 # Usage: reverse.py <zone_filename>...
   4 #
   5 # This demo script will load in all of the zones specified by the
   6 # filenames on the command line, find all the A RRs in them, and
   7 # construct a reverse mapping table that maps each IP address used to
   8 # the list of names mapping to that address.  The table is then sorted
   9 # nicely and printed.
  10 #
  11 # Note!  The zone name is taken from the basename of the filename, so
  12 # you must use filenames like "/wherever/you/like/dnspython.org" and
  13 # not something like "/wherever/you/like/foo.db" (unless you're
  14 # working with the ".db" GTLD, of course :)).
  15 #
  16 # If this weren't a demo script, there'd be a way of specifying the
  17 # origin for each zone instead of constructing it from the filename.
  18
  19 import dns.zone
  20 import dns.ipv4
  21 import os.path
  22 import sys
  23
  24 reverse_map = {}
  25
  26 for filename in sys.argv[1:]:
  27     zone = dns.zone.from_file(filename, os.path.basename(filename),
  28                               relativize=False)
  29     for (name, ttl, rdata) in zone.iterate_rdatas('A'):
  30         try:
  31             reverse_map[rdata.address].append(name.to_text())
  32         except KeyError:
  33             reverse_map[rdata.address] = [name.to_text()]
  34
  35 keys = reverse_map.keys()
  36 keys.sort(lambda a1, a2: cmp(dns.ipv4.inet_aton(a1), dns.ipv4.inet_aton(a2)))
  37 for k in keys:
  38     v = reverse_map[k]
  39     v.sort()
  40     print k, v