freeipa/install/tools/ipa-replica-conncheck

#! /usr/bin/python2 -E
# Authors: Martin Kosek <mkosek@redhat.com>
#
# Copyright (C) 2011  Red Hat
# see file 'COPYING' for use and warranty information
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#

from ipapython.config import IPAOptionParser
from ipapython import version
from ipapython import ipautil
from ipapython import dogtag
from ipapython.ipautil import CalledProcessError
from ipaserver.install import installutils
import ipaclient.ipachangeconf
from optparse import OptionGroup
from ipapython.ipa_log_manager import *
import sys
import os
import signal
import tempfile
import socket
import time
import threading
import errno
from socket import SOCK_STREAM, SOCK_DGRAM
import distutils.spawn

CONNECT_TIMEOUT = 5
RESPONDERS = [ ]
QUIET = False
CCACHE_FILE = "/etc/ipa/.conncheck_ccache"
KRB5_CONFIG = None

class SshExec(object):
    def __init__(self, user, addr):
        self.user = user
        self.addr = addr
        self.cmd = distutils.spawn.find_executable('ssh')

    def __call__(self, command, verbose=False):
        # Bail if ssh is not installed
        if self.cmd is None:
            print "WARNING: ssh not installed, skipping ssh test"
            return ('', '', 0)

        tmpf = tempfile.NamedTemporaryFile()
        cmd = [
            self.cmd,
            '-o StrictHostKeychecking=no',
            '-o UserKnownHostsFile=%s' % tmpf.name,
            '%s@%s' % (self.user, self.addr), command
        ]
        if verbose:
            cmd.insert(1, '-v')

        env = {'KRB5_CONFIG': KRB5_CONFIG, 'KRB5CCNAME': CCACHE_FILE}
        return ipautil.run(cmd, env=env, raiseonerr=False)


class CheckedPort(object):
    def __init__(self, port, port_type, description):
        self.port = port
        self.port_type = port_type
        self.description = description

BASE_PORTS = [
                CheckedPort(389, SOCK_STREAM, "Directory Service: Unsecure port"),
                CheckedPort(636, SOCK_STREAM, "Directory Service: Secure port"),
                CheckedPort(88, SOCK_STREAM, "Kerberos KDC: TCP"),
                CheckedPort(88, SOCK_DGRAM, "Kerberos KDC: UDP"),
                CheckedPort(464, SOCK_STREAM, "Kerberos Kpasswd: TCP"),
                CheckedPort(464, SOCK_DGRAM, "Kerberos Kpasswd: UDP"),
                CheckedPort(80, SOCK_STREAM, "HTTP Server: Unsecure port"),
                CheckedPort(443, SOCK_STREAM, "HTTP Server: Secure port"),
             ]


def print_info(msg):
    if not QUIET:
        print msg

def parse_options():
    parser = IPAOptionParser(version=version.VERSION)

    replica_group = OptionGroup(parser, "on-replica options")
    replica_group.add_option("-m", "--master", dest="master",
                      help="Master address with running IPA for output connection check")
    replica_group.add_option("-a", "--auto-master-check", dest="auto_master_check",
                      action="store_true",
                      default=False,
                      help="Automatically execute connection check on master")
    replica_group.add_option("-r", "--realm", dest="realm",
                      help="Realm name")
    replica_group.add_option("-k", "--kdc", dest="kdc",
                      help="Master KDC. Defaults to master address")
    replica_group.add_option("-p", "--principal", dest="principal",
                      default="admin", help="Principal to use to log in to remote master")
    replica_group.add_option("-w", "--password", dest="password", sensitive=True,
                      help="Password for the principal"),
    parser.add_option_group(replica_group)


    master_group = OptionGroup(parser, "on-master options")
    master_group.add_option("-R", "--replica", dest="replica",
                      help="Address of remote replica machine to check against")
    parser.add_option_group(master_group)

    common_group = OptionGroup(parser, "common options")
    common_group.add_option("-c", "--check-ca", dest="check_ca",
                      action="store_true",
                      default=False,
                      help="Check also ports for Certificate Authority "
                        "(for servers installed before IPA 3.1)")

    common_group.add_option("", "--hostname", dest="hostname",
                      help="The hostname of this server (FQDN). "
                           "By default a nodename from uname(2) is used.")
    parser.add_option_group(common_group)

    parser.add_option("-d", "--debug", dest="debug",
                      action="store_true",
                      default=False, help="Print debugging information")
    parser.add_option("-q", "--quiet", dest="quiet",
                      action="store_true",
                      default=False, help="Output only errors")

    options, args = parser.parse_args()
    safe_options = parser.get_safe_opts(options)

    if options.master and options.replica:
        parser.error("on-master and on-replica options are mutually exclusive!")

    if options.master:
        if options.auto_master_check and not options.realm:
            parser.error("Realm is parameter is required to connect to remote master!")
        if not os.getegid() == 0:
            parser.error("You can only run on-replica part as root.")

    if options.master and not options.kdc:
       options.kdc = options.master

    if not options.master and not options.replica:
       parser.error("No action: you should select either --replica or --master option.")

    if not options.hostname:
        options.hostname = socket.getfqdn()

    if options.quiet:
        global QUIET
        QUIET = True

    return safe_options, options

def logging_setup(options):
    log_file = None

    if os.getegid() == 0:
        log_file = "/var/log/ipareplica-conncheck.log"

    standard_logging_setup(log_file, debug=options.debug)

def clean_responders(responders):
    if not responders:
        return

    for responder in responders:
        responder.stop()

    for responder in responders:
        responder.join()
        responders.remove(responder)

def sigterm_handler(signum, frame):
    # do what SIGINT does (raise a KeyboardInterrupt)
    sigint_handler = signal.getsignal(signal.SIGINT)
    if callable(sigint_handler):
        sigint_handler(signum, frame)

def configure_krb5_conf(realm, kdc, filename):

    krbconf = ipaclient.ipachangeconf.IPAChangeConf("IPA Installer")
    krbconf.setOptionAssignment((" = ", " "))
    krbconf.setSectionNameDelimiters(("[","]"))
    krbconf.setSubSectionDelimiters(("{","}"))
    krbconf.setIndent(("","  ","    "))

    opts = [{'name':'comment', 'type':'comment', 'value':'File created by ipa-replica-conncheck'},
            {'name':'empty', 'type':'empty'}]

    #[libdefaults]
    libdefaults = [{'name':'default_realm', 'type':'option', 'value':realm}]
    libdefaults.append({'name':'dns_lookup_realm', 'type':'option', 'value':'false'})
    libdefaults.append({'name':'dns_lookup_kdc', 'type':'option', 'value':'true'})
    libdefaults.append({'name':'rdns', 'type':'option', 'value':'false'})
    libdefaults.append({'name':'ticket_lifetime', 'type':'option', 'value':'24h'})
    libdefaults.append({'name':'forwardable', 'type':'option', 'value':'yes'})

    opts.append({'name':'libdefaults', 'type':'section', 'value': libdefaults})
    opts.append({'name':'empty', 'type':'empty'})

    #the following are necessary only if DNS discovery does not work
    #[realms]
    realms_info =[{'name':'kdc', 'type':'option', 'value':ipautil.format_netloc(kdc, 88)},
                 {'name':'master_kdc', 'type':'option', 'value':ipautil.format_netloc(kdc, 88)},
                 {'name':'admin_server', 'type':'option', 'value':ipautil.format_netloc(kdc, 749)}]
    realms = [{'name':realm, 'type':'subsection', 'value':realms_info}]

    opts.append({'name':'realms', 'type':'section', 'value':realms})
    opts.append({'name':'empty', 'type':'empty'})

    #[appdefaults]
    pamopts = [{'name':'debug', 'type':'option', 'value':'false'},
               {'name':'ticket_lifetime', 'type':'option', 'value':'36000'},
               {'name':'renew_lifetime', 'type':'option', 'value':'36000'},
               {'name':'forwardable', 'type':'option', 'value':'true'},
               {'name':'krb4_convert', 'type':'option', 'value':'false'}]
    appopts = [{'name':'pam', 'type':'subsection', 'value':pamopts}]
    opts.append({'name':'appdefaults', 'type':'section', 'value':appopts})

    root_logger.debug("Writing temporary Kerberos configuration to %s:\n%s"
                              % (filename, krbconf.dump(opts)))

    krbconf.newConf(filename, opts)

class PortResponder(threading.Thread):

    def __init__(self, port, port_type, socket_timeout=1):
        super(PortResponder, self).__init__()
        self.port = port
        self.port_type = port_type
        self.socket_timeout = socket_timeout
        self._stop_request = False

    def run(self):
        while not self._stop_request:
            try:
                ipautil.bind_port_responder(self.port,
                        self.port_type,
                        socket_timeout=self.socket_timeout,
                        responder_data="FreeIPA")
            except socket.timeout:
                pass
            except socket.error, e:
                if e.errno == errno.EADDRINUSE:
                    time.sleep(1)
                else:
                    raise

    def stop(self):
        self._stop_request = True

def port_check(host, port_list):
    ports_failed = []
    ports_udp_warning = []  # conncheck could not verify that port is open
    for port in port_list:
        try:
            port_open = ipautil.host_port_open(host, port.port,
                    port.port_type, socket_timeout=CONNECT_TIMEOUT)
        except socket.gaierror:
            raise RuntimeError("Port check failed! Unable to resolve host name '%s'" % host)
        if port_open:
            result = "OK"
        else:
            if port.port_type == socket.SOCK_DGRAM:
                ports_udp_warning.append(port)
                result = "WARNING"
            else:
                ports_failed.append(port)
                result = "FAILED"
        print_info("   %s (%d): %s" % (port.description, port.port, result))

    if ports_udp_warning:
        print "The following UDP ports could not be verified as open: %s" \
                % ", ".join(str(port.port) for port in ports_udp_warning)
        print "This can happen if they are already bound to an application"
        print "and ipa-replica-conncheck cannot attach own UDP responder."

    if ports_failed:
        msg_ports = []
        for port in ports_failed:
            port_type_text = "TCP" if port.port_type == SOCK_STREAM else "UDP"
            msg_ports.append('%d (%s)' % (port.port, port_type_text))
        raise RuntimeError("Port check failed! Inaccessible port(s): %s" \
                % ", ".join(msg_ports))

def main():
    safe_options, options = parse_options()

    logging_setup(options)
    root_logger.debug('%s was invoked with options: %s' % (sys.argv[0], safe_options))
    root_logger.debug("missing options might be asked for interactively later\n")

    signal.signal(signal.SIGTERM, sigterm_handler)

    required_ports = BASE_PORTS
    if options.check_ca:
        # Check old Dogtag CA replication port
        # New installs with unified databases use main DS port (checked above)
        required_ports.append(CheckedPort(dogtag.Dogtag9Constants.DS_PORT,
            SOCK_STREAM, "PKI-CA: Directory Service port"))

    if options.replica:
        print_info("Check connection from master to remote replica '%s':" % options.replica)
        port_check(options.replica, required_ports)
        print_info("\nConnection from master to replica is OK.")

    # kinit to foreign master
    if options.master:
        # check ports on master first
        print_info("Check connection from replica to remote master '%s':" % options.master)
        tcp_ports = [ port for port in required_ports if port.port_type == SOCK_STREAM ]
        udp_ports = [ port for port in required_ports if port.port_type == SOCK_DGRAM ]
        port_check(options.master, tcp_ports)

        if udp_ports:
            print_info("\nThe following list of ports use UDP protocol and would need to be")
            print_info("checked manually:")
            for port in udp_ports:
                result = "SKIPPED"
                print_info("   %s (%d): %s" % (port.description, port.port, result))

        print_info("\nConnection from replica to master is OK.")

        # create listeners
        global RESPONDERS
        print_info("Start listening on required ports for remote master check")

        for port in required_ports:
            root_logger.debug("Start listening on port %d (%s)" % (port.port, port.description))
            responder = PortResponder(port.port, port.port_type)
            responder.start()
            RESPONDERS.append(responder)

        remote_check_opts = ['--replica %s' % options.hostname]

        if options.auto_master_check:
            (krb_fd, krb_name) = tempfile.mkstemp()
            os.close(krb_fd)
            configure_krb5_conf(options.realm, options.kdc, krb_name)
            global KRB5_CONFIG
            KRB5_CONFIG = krb_name

            print_info("Get credentials to log in to remote master")
            if options.principal.find('@') == -1:
                principal = '%s@%s' % (options.principal, options.realm)
                user = options.principal
            else:
                principal = options.principal
                user = options.principal.partition('@')[0]

            if options.password:
                password=options.password
            else:
                password = installutils.read_password(principal, confirm=False,
                           validate=False, retry=False)
                if password is None:
                    sys.exit("Principal password required")


            stderr=''
            (stdout, stderr, returncode) = ipautil.run(['/usr/bin/kinit', principal],
                 env={'KRB5_CONFIG':KRB5_CONFIG, 'KRB5CCNAME':CCACHE_FILE},
                 stdin=password, raiseonerr=False)
            if returncode != 0:
                raise RuntimeError("Cannot acquire Kerberos ticket: %s" % stderr)

            # Verify kinit was actually successful
            stderr=''
            (stdout, stderr, returncode) = ipautil.run(['/usr/bin/kvno',
                 'host/%s' % options.master],
                 env={'KRB5_CONFIG':KRB5_CONFIG, 'KRB5CCNAME':CCACHE_FILE},
                 raiseonerr=False)
            if returncode != 0:
                raise RuntimeError("Could not get ticket for master server: %s" % stderr)

            ssh = SshExec(user, options.master)

            print_info("Check SSH connection to remote master")
            stdout, stderr, returncode = ssh('echo OK', verbose=True)
            if returncode != 0:
                print 'Could not SSH into remote host. Error output:'
                for line in stderr.splitlines():
                    print '    %s' % line
                raise RuntimeError('Could not SSH to remote host.')

            print_info("Execute check on remote master")
            stdout, stderr, returncode = ssh(
                "/usr/sbin/ipa-replica-conncheck " +
                    " ".join(remote_check_opts))
            print_info(stdout)
            if returncode != 0:
                raise RuntimeError("Remote master check failed with following error message(s):\n%s" % stderr)
        else:
            # wait until user  test is ready
            print_info("Listeners are started. Use CTRL+C to terminate the listening part after the test.")
            print_info("")
            print_info("Please run the following command on remote master:")

            print_info("/usr/sbin/ipa-replica-conncheck " + " ".join(remote_check_opts))
            time.sleep(3600)
            print_info("Connection check timeout: terminating listening program")

if __name__ == "__main__":
    try:
        sys.exit(main())
    except SystemExit, e:
        sys.exit(e)
    except KeyboardInterrupt:
        print_info("\nCleaning up...")
        sys.exit(1)
    except RuntimeError, e:
        sys.exit(e)
    finally:
        clean_responders(RESPONDERS)
        for file_name in (CCACHE_FILE, KRB5_CONFIG):
            if file_name:
                try:
                    os.remove(file_name)
                except OSError:
                    pass