Coverage for airflow.security.kerberos : 27%

#!/usr/bin/env python 

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import logging 

import subprocess 

import sys 

import time 

import socket 

from airflow.configuration import conf 

LOG = logging.getLogger(__name__) 

NEED_KRB181_WORKAROUND=None 

def renew_from_kt(): 

    # The config is specified in seconds. But we ask for that same amount in 

    # minutes to give ourselves a large renewal buffer. 

    renewal_lifetime = "%sm" % conf.getint('kerberos', 'reinit_frequency') 

    principal = "%s/%s" % (conf.get('kerberos', 'principal'), socket.getfqdn()) 

    cmdv = [conf.get('kerberos', 'kinit_path'), 

            "-r", renewal_lifetime, 

            "-k", # host ticket 

            "-t", conf.get('kerberos', 'keytab'),   # specify keytab 

            "-c", conf.get('kerberos', 'ccache'),   # specify credentials cache 

            principal] 

    LOG.info("Reinitting kerberos from keytab: " + 

             " ".join(cmdv)) 

    subp = subprocess.Popen(cmdv, 

                            stdout=subprocess.PIPE, 

                            stderr=subprocess.PIPE, 

                            close_fds=True, 

                            bufsize=-1) 

    subp.wait() 

    if subp.returncode != 0: 

        LOG.error("Couldn't reinit from keytab! `kinit' exited with %s.\n%s\n%s" % ( 

            subp.returncode, 

            "\n".join(subp.stdout.readlines()), 

            "\n".join(subp.stderr.readlines()))) 

        sys.exit(subp.returncode) 

    global NEED_KRB181_WORKAROUND 

    if NEED_KRB181_WORKAROUND is None: 

        NEED_KRB181_WORKAROUND = detect_conf_var() 

    if NEED_KRB181_WORKAROUND: 

        # (From: HUE-640). Kerberos clock have seconds level granularity. Make sure we 

        # renew the ticket after the initial valid time. 

        time.sleep(1.5) 

        perform_krb181_workaround() 

def perform_krb181_workaround(): 

    cmdv = [conf.get('kerberos', 'kinit_path'), 

            "-R", 

            "-c", conf.get('kerberos', 'ccache')] 

    LOG.info("Renewing kerberos ticket to work around kerberos 1.8.1: " + 

             " ".join(cmdv)) 

    ret = subprocess.call(cmdv) 

    if ret != 0: 

        principal = "%s/%s" % (conf.get('kerberos', 'principal'), socket.getfqdn()) 

        fmt_dict = dict(princ=principal, 

                        ccache=conf.get('kerberos', 'principal')) 

        LOG.error("Couldn't renew kerberos ticket in order to work around " 

                  "Kerberos 1.8.1 issue. Please check that the ticket for " 

                  "'%(princ)s' is still renewable:\n" 

                  "  $ kinit -f -c %(ccache)s\n" 

                  "If the 'renew until' date is the same as the 'valid starting' " 

                  "date, the ticket cannot be renewed. Please check your KDC " 

                  "configuration, and the ticket renewal policy (maxrenewlife) " 

                  "for the '%(princ)s' and `krbtgt' principals." % fmt_dict) 

        sys.exit(ret) 

def detect_conf_var(): 

    """Return true if the ticket cache contains "conf" information as is found 

    in ticket caches of Kerboers 1.8.1 or later. This is incompatible with the 

    Sun Java Krb5LoginModule in Java6, so we need to take an action to work 

    around it. 

    """ 

    f = file(conf.get('kerberos', 'ccache'), "rb") 

    try: 

        data = f.read() 

        return "X-CACHECONF:" in data 

    finally: 

        f.close() 

def run(): 

    if conf.get('kerberos','keytab') is None: 

        LOG.debug("Keytab renewer not starting, no keytab configured") 

        sys.exit(0) 

    while True: 

        renew_from_kt() 

        time.sleep(conf.getint('kerberos', 'reinit_frequency'))