check_expire/ianardap.py
2021-07-07 15:23:26 +02:00

115 lines
4.0 KiB
Python
Executable File

#!/usr/bin/env python3
"""A simple module to get the RDAP server for a given domain name,
from the IANA database specified in RFC 7484.
"""
# http://python-requests.org/ for easier HTTPS retrieval
import requests
import datetime
import json
import os
import sys
import time
import fcntl
IANABASE = "https://data.iana.org/rdap/dns.json"
CACHE = os.environ["HOME"] + "/.ianardapcache.json"
MAXAGE = 24 # Hours
IANATIMEOUT = 10 # Seconds
MAXTESTS = 3 # Maximum attempts to get the database
class IanaRDAPDatabase():
def __init__(self, maxage=MAXAGE, cachefile=CACHE):
""" Retrieves the IANA databse, if not already cached. maxage is in hours. """
cache_valid = False
self.cachefile = cachefile
self.lockname = self.cachefile + ".lock"
loaded = False
tests = 0
errmsg = "No error"
while not loaded and tests < MAXTESTS:
self.lock()
if os.path.exists(cachefile) and \
datetime.datetime.fromtimestamp(os.path.getmtime(cachefile)) > \
(datetime.datetime.now() - datetime.timedelta(hours = maxage)):
cache = open(cachefile, "rb")
content = cache.read()
cache.close()
self.unlock()
try:
database = json.loads(content)
loaded = True
self.retrieved = datetime.datetime.fromtimestamp(os.path.getmtime(cachefile))
cache_valid = True
except json.decoder.JSONDecodeError:
tests += 1
errmsg = "Invalid JSON content in %s" % cachefile
# Delete it without mercy
os.remove(cachefile)
continue
else:
self.unlock()
response = requests.get(IANABASE, timeout=IANATIMEOUT)
if response.status_code != 200:
time.sleep(2)
tests += 1
errmsg = "Invalid HTTPS return code when trying to get %s: %s" % (IANABASE, response.status_code)
continue
else:
loaded = True
self.retrieved = datetime.datetime.now()
try:
content = response.content
database = json.loads(content)
except json.decoder.JSONDecodeError:
tests += 1
errmsg = "Invalid JSON retrieved from %s" % IANABASE
continue
if not loaded:
raise Exception("Cannot read IANA database: %s" % errmsg)
self.description = database["description"]
self.publication = database["publication"]
self.version = database["version"]
self.services = {}
for service in database["services"]:
for tld in service[0]:
for server in service[1]:
self.services[tld] = server
if not cache_valid:
self.lock()
cache = open(cachefile, "wb")
cache.write(content)
cache.close()
self.unlock()
def lock(self):
self.lockhandle = open(self.lockname, 'w')
fcntl.lockf(self.lockhandle, fcntl.LOCK_EX)
def unlock(self):
fcntl.lockf(self.lockhandle, fcntl.LOCK_UN)
self.lockhandle.close()
def find(self, domain):
""" Get the RDAP server for a given domain name. None if there is none."""
if domain.endswith("."):
domain = domain[:-1]
labels = domain.split(".")
tld = labels[len(labels)-1]
if tld in self.services:
return self.services[tld]
else:
return None
if __name__ == "__main__":
rdap = IanaRDAPDatabase(maxage=1)
print("Database \"%s\", version %s published on %s, retrieved on %s, %i services" % \
(rdap.description, rdap.version, rdap.publication, rdap.retrieved, len(rdap.services)))
for domain in sys.argv[1:]:
print("%s -> %s" % (domain, rdap.find(domain)))