#! /usr/bin/python -E
# Authors: Simo Sorce <ssorce@redhat.com>
#          Karl MacMillan <kmacmillan@mentalrootkit.com>
#
# Copyright (C) 2007  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; version 2 only
#
# 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, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#

try:
    import sys
    from distutils.sysconfig import get_python_lib
    sys.path.append("%s/%s" % (get_python_lib(), "ipaclient"))

    import os
    import krbV
    import socket
    import logging
    import tempfile
    import getpass
    from optparse import OptionParser
    import ipaclient.ipadiscovery
    import ipaclient.ipachangeconf
    import ipaclient.ntpconf
    from ipapython.ipautil import run, user_input, file_exists
    from ipapython import sysrestore
    from ipapython import version
    import SSSDConfig
except ImportError:
    print >> sys.stderr, """\
There was a problem importing one of the required Python modules. The
error was:

    %s
""" % sys.exc_value
    sys.exit(1)


def parse_options():
    parser = OptionParser(version=version.VERSION)
    parser.add_option("--domain", dest="domain", help="domain name")
    parser.add_option("--server", dest="server", help="IPA server")
    parser.add_option("--realm", dest="realm_name", help="realm name")
    parser.add_option("-f", "--force", dest="force", action="store_true",
                      default=False, help="force setting of ldap/kerberos conf")
    parser.add_option("-d", "--debug", dest="debug", action="store_true",
                      default=False, help="print debugging information")
    parser.add_option("-U", "--unattended", dest="unattended",
                      action="store_true",
                      help="unattended installation never prompts the user")
    parser.add_option("--ntp-server", dest="ntp_server", help="ntp server to use")
    parser.add_option("-S", "--no-sssd", action="store_false",
                      help="do not configure sssd", default=True, dest="sssd")
    parser.add_option("-N", "--no-ntp", action="store_false",
                      help="do not configure ntp", default=True, dest="conf_ntp")
    parser.add_option("-w", "--password", dest="password",
                      help="password to join the IPA realm"),
    parser.add_option("-W", dest="prompt_password", action="store_true",
                      default=False,
                      help="Prompt for a password to join the IPA realm"),
    parser.add_option("-p", "--principal", dest="principal",
                      help="principal to use to join the IPA realm"),
    parser.add_option("--on-master", dest="on_master", action="store_true",
                      help="use this option when run on a master", default=False)
    parser.add_option("--permit", dest="permit", action="store_true",
                      help="disable access rules by default, permit all access.", default=False)
    parser.add_option("", "--uninstall", dest="uninstall", action="store_true",
                      default=False, help="uninstall an existing installation")

    options, args = parser.parse_args()

    if (options.server and not options.domain):
        parser.error("--server cannot be used without providing --domain")

    return options

def logging_setup(options):
    # Always log everything (i.e., DEBUG) to the log
    # file.

    log_file = "/var/log/ipaclient-install.log"
    if options.uninstall:
        log_file = "/var/log/ipaclient-uninstall.log"

    old_umask = os.umask(077)
    logging.basicConfig(level=logging.DEBUG,
                        format='%(asctime)s %(levelname)s %(message)s',
                        filename=log_file,
                        filemode='w')
    os.umask(old_umask)

    console = logging.StreamHandler()
    # If the debug option is set, also log debug messages to the console
    if options.debug:
        console.setLevel(logging.DEBUG)
    else:
        # Otherwise, log critical and error messages
        console.setLevel(logging.ERROR)
    formatter = logging.Formatter('%(name)-12s: %(levelname)-8s %(message)s')
    console.setFormatter(formatter)
    logging.getLogger('').addHandler(console)

def uninstall(options):

    print "Restoring client configuration files"
    fstore.restore_all_files()

    # Remove our host cert
    try:
        run(["/usr/bin/ipa-getcert", "stop-tracking", "-d", "/etc/pki/nssdb", "-n", "Server-Cert"])
        run(["/usr/bin/certutil", "-D", "-d", "/etc/pki/nssdb", "-n", "Server-Cert"])
    except Exception, e:
        print "Failed to remove Server-Cert from /etc/pki/nssdb: %s" % str(e)
 
    try:
        run(["/sbin/service", "certmonger", "stop"])
    except:
        print "Failed to stop the certmonger daemon"

    try:
        run(["/sbin/chkconfig", "certmonger", "off"])
    except:
        print "Failed to disable automatic startup of the certmonger daemon"

    print "Disabling client Kerberos and Ldap configurations"
    try:
        run(["/usr/sbin/authconfig", "--disableldap", "--disablekrb5", "--disablesssd", "--disablesssdauth", "--update"])
    except Exception, e:
        print "Failed to remove krb5/ldap configuration. " +str(e)
        sys.exit(1)

    print "Removing Kerberos service principals from /etc/krb5.keytab"
    try:
        run(["/sbin/service", "nscd", "restart"])
    except:
        print "Failed to restart start the NSCD daemon"

    try:
        ctx = krbV.default_context()
        run(["/usr/sbin/ipa-rmkeytab", "-k", "/etc/krb5.keytab", "-r", ctx.default_realm])
    except:
        print "Failed to clean up /etc/krb5.keytab"

    if not options.unattended:
        print "The original nsswitch.conf configuration has been restored."
        print "You may need to restart services or reboot the machine."
        if not options.on_master:
            if user_input("Do you want to reboot the machine?", False):
                try:
                    run(["/usr/bin/reboot"])
                except Exception, e:
                    print "Reboot command failed to exceute. " + str(e)
                    sys.exit(1)

def configure_ipa_conf(fstore, cli_basedn, cli_realm, cli_domain, cli_server):
    ipaconf = ipaclient.ipachangeconf.IPAChangeConf("IPA Installer")
    ipaconf.setOptionAssignment(" = ")
    ipaconf.setSectionNameDelimiters(("[","]"))

    opts = [{'name':'comment', 'type':'comment', 'value':'File modified by ipa-client-install'},
            {'name':'empty', 'type':'empty'}]

    #[global]
    defopts = [{'name':'basedn', 'type':'option', 'value':cli_basedn},
               {'name':'realm', 'type':'option', 'value':cli_realm},
               {'name':'domain', 'type':'option', 'value':cli_domain},
               {'name':'server', 'type':'option', 'value':cli_server},
               {'name':'xmlrpc_uri', 'type':'option', 'value':'https://%s/ipa/xml' % cli_server}]

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

    fstore.backup_file("/etc/ipa/default.conf")
    ipaconf.newConf("/etc/ipa/default.conf", opts)

    return 0

def configure_ldap_conf(fstore, cli_basedn, cli_realm, cli_domain, cli_server, dnsok, options):
    ldapconf = ipaclient.ipachangeconf.IPAChangeConf("IPA Installer")
    ldapconf.setOptionAssignment(" ")

    opts = [{'name':'comment', 'type':'comment', 'value':'File modified by ipa-client-install'},
            {'name':'empty', 'type':'empty'},
            {'name':'ldap_version', 'type':'option', 'value':'3'},
            {'name':'base', 'type':'option', 'value':cli_basedn},
            {'name':'empty', 'type':'empty'},
            {'name':'nss_base_passwd', 'type':'option', 'value':'cn=users,cn=accounts,'+cli_basedn+'?sub'},
            {'name':'nss_base_group', 'type':'option', 'value':'cn=groups,cn=accounts,'+cli_basedn+'?sub'},
            {'name':'nss_schema', 'type':'option', 'value':'rfc2307bis'},
            {'name':'nss_map_attribute', 'type':'option', 'value':'uniqueMember member'},
            {'name':'nss_initgroups_ignoreusers', 'type':'option', 'value':'root,dirsrv'},
            {'name':'empty', 'type':'empty'},
            {'name':'nss_reconnect_maxsleeptime', 'type':'option', 'value':'8'},
            {'name':'nss_reconnect_sleeptime', 'type':'option', 'value':'1'},
            {'name':'bind_timelimit', 'type':'option', 'value':'5'},
            {'name':'timelimit', 'type':'option', 'value':'15'},
            {'name':'empty', 'type':'empty'}]
    if not dnsok or options.force or options.on_master:
        if options.on_master:
            opts.append({'name':'uri', 'type':'option', 'value':'ldap://localhost'})
        else:
            opts.append({'name':'uri', 'type':'option', 'value':'ldap://'+cli_server})
    else:
        opts.append({'name':'nss_srv_domain', 'type':'option', 'value':cli_domain})

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

    # Depending on the release and distribution this may exist in any 
    # number of different file names, update what we find
    for filename in ['/etc/ldap.conf', '/etc/nss_ldap.conf', '/etc/libnss-ldap.conf']:
        if file_exists(filename):
            try:
                fstore.backup_file(filename)
                ldapconf.newConf(filename, opts)
            except Exception, e:
                print "Creation of %s: %s" % (filename, str(e))
                return 1

    return 0

def configure_nslcd_conf(fstore, cli_basedn, cli_realm, cli_domain, cli_server, dnsok, options):
    nslcdconf = ipaclient.ipachangeconf.IPAChangeConf("IPA Installer")
    nslcdconf.setOptionAssignment(" ")

    opts = [{'name':'comment', 'type':'comment', 'value':'File modified by ipa-client-install'},
            {'name':'empty', 'type':'empty'},
            {'name':'ldap_version', 'type':'option', 'value':'3'},
            {'name':'base', 'type':'option', 'value':cli_basedn},
            {'name':'empty', 'type':'empty'},
            {'name':'base passwd', 'type':'option', 'value':'cn=users,cn=accounts,'+cli_basedn},
            {'name':'base group', 'type':'option', 'value':'cn=groups,cn=accounts,'+cli_basedn},
            {'name':'map group', 'type':'option', 'value':'uniqueMember member'},
            {'name':'timelimit', 'type':'option', 'value':'15'},
            {'name':'empty', 'type':'empty'}]
    if not dnsok or options.force or options.on_master:
        if options.on_master:
            opts.append({'name':'uri', 'type':'option', 'value':'ldap://localhost'})
        else:
            opts.append({'name':'uri', 'type':'option', 'value':'ldap://'+cli_server})
    else:
        opts.append({'name':'uri', 'type':'option', 'value':'DNS'})

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

    if file_exists('/etc/nslcd.conf'):
        try:
            fstore.backup_file('/etc/nslcd.conf')
            nslcdconf.newConf('/etc/nslcd.conf', opts)
        except Exception, e:
            print "Creation of %s: %s" % ('/etc/nslcd.conf', str(e))
            return 1

    return 0

def hardcode_ldap_server(cli_server):
    """
    DNS Discovery didn't return a valid IPA server, hardcode a value into
    the file instead.
    """
    ldapconf = ipaclient.ipachangeconf.IPAChangeConf("IPA Installer")
    ldapconf.setOptionAssignment(" ")

    opts = [{'name':'uri', 'type':'option', 'action':'set', 'value':'ldap://'+cli_server},
            {'name':'empty', 'type':'empty'}]

    # Errors raised by this should be caught by the caller
    ldapconf.changeConf("/etc/ldap.conf", opts)

    return

def configure_krb5_conf(fstore, cli_basedn, cli_realm, cli_domain, cli_server, dnsok, options, filename):

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

    opts = [{'name':'comment', 'type':'comment', 'value':'File modified by ipa-client-install'},
            {'name':'empty', 'type':'empty'}]

    #[libdefaults]
    libopts = [{'name':'default_realm', 'type':'option', 'value':cli_realm}]
    if not dnsok or options.force:
        libopts.append({'name':'dns_lookup_realm', 'type':'option', 'value':'false'})
        libopts.append({'name':'dns_lookup_kdc', 'type':'option', 'value':'false'})
    else:
        libopts.append({'name':'dns_lookup_realm', 'type':'option', 'value':'true'})
        libopts.append({'name':'dns_lookup_kdc', 'type':'option', 'value':'true'})
    libopts.append({'name':'ticket_lifetime', 'type':'option', 'value':'24h'})
    libopts.append({'name':'forwardable', 'type':'option', 'value':'yes'})

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

    #the following are necessary only if DNS discovery does not work
    if not dnsok or options.force:
        #[realms]
        kropts =[{'name':'kdc', 'type':'option', 'value':cli_server+':88'},
                 {'name':'admin_server', 'type':'option', 'value':cli_server+':749'},
                 {'name':'default_domain', 'type':'option', 'value':cli_domain}]
        ropts = [{'name':cli_realm, 'type':'subsection', 'value':kropts}]
        opts.append({'name':'realms', 'type':'section', 'value':ropts})
        opts.append({'name':'empty', 'type':'empty'})

    #[domain_realm]
    dropts = [{'name':'.'+cli_domain, 'type':'option', 'value':cli_realm},
              {'name':cli_domain, 'type':'option', 'value':cli_realm}]
    opts.append({'name':'domain_realm', 'type':'section', 'value':dropts})
    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})

    krbconf.newConf(filename, opts);

    return 0

def configure_certmonger(fstore, options):
    started = True

    try:
        run(["/sbin/service", "certmonger", "restart"])
    except:
        print "Failed to start the certmonger daemon"
        print "Automatic certificate management will not be available"
        started = False

    try:
        run(["/sbin/chkconfig", "certmonger", "on"])
    except:
        print "Failed to configure automatic startup of the certmonger daemon"
        print "Automatic certificate management will not be available"

    # Request our host cert
    if started:
        try:
            run(["ipa-getcert", "request", "-d", "/etc/pki/nssdb", "-n", "Server-Cert"])
        except:
            print "certmonger request for host certificate failed"

def configure_sssd_conf(fstore, cli_domain, cli_server, options):
    fstore.backup_file("/etc/sssd/sssd.conf")
    sssdconfig = SSSDConfig.SSSDConfig()
    sssdconfig.new_config()

    domain = sssdconfig.new_domain(cli_domain)
    domain.add_provider('ipa', 'id')

    domain.set_option('ipa_server', cli_server)
    domain.set_option('ipa_domain', cli_domain)

    # Might need this if /bin/hostname doesn't return a FQDN
    #domain.set_option('ipa_hostname', 'client.example.com')

    domain.add_provider('ipa', 'auth')
    domain.add_provider('ipa', 'chpass')
    if not options.permit:
        domain.add_provider('ipa', 'access')
    else:
        domain.add_provider('permit', 'access')

    domain.set_option('cache_credentials', True)

    domain.set_active(True)

    sssdconfig.save_domain(domain)
    sssdconfig.write("/etc/sssd/sssd.conf")

    return 0

def main():
    options = parse_options()
    logging_setup(options)
    dnsok = True

    global fstore
    fstore = sysrestore.FileStore('/var/lib/ipa-client/sysrestore')

    if options.uninstall:
        return uninstall(options)

    cli_domain = None
    cli_server = None
    cli_realm = None
    cli_basedn = None

    if options.unattended and (options.password is None and options.principal is None and options.prompt_password is False) and not options.on_master:
        print "One of password and principal are required."
        return 1

    # Create the discovery instance
    ds = ipaclient.ipadiscovery.IPADiscovery()

    ret = ds.search(domain=options.domain, server=options.server)
    if ret == -10:
        print "Can't get the fully qualified name of this host"
        print "Please check that the client is properly configured"
        return ret
    if ret == -1 or not ds.getDomainName():
        logging.debug("Domain not found")
        if options.domain:
            cli_domain = options.domain
        elif options.unattended:
            return ret
        else:
            print "DNS discovery failed to determine your DNS domain"
            cli_domain = user_input("Please provide the domain name of your IPA server (ex: example.com)", allow_empty = False)
        ret = ds.search(domain=cli_domain, server=options.server)
    if not cli_domain:
        if ds.getDomainName():
            cli_domain = ds.getDomainName()

    if ret == -2 or not ds.getServerName():
        dnsok = False
        logging.debug("IPA Server not found")
        if options.server:
            cli_server = options.server
        elif options.unattended:
            return ret
        else:
            print "DNS discovery failed to find the IPA Server"
            cli_server = user_input("Please provide your IPA server name (ex: ipa.example.com)", allow_empty = False)
        ret = ds.search(domain=cli_domain, server=cli_server)
    if not cli_server:
        if ds.getServerName():
            cli_server = ds.getServerName()

    if ret != 0:
        print "Failed to verify that "+cli_server+" is an IPA Server."
        print "This may mean that the remote server is not up or is not reachable"
        print "due to network or firewall settings."
        return ret

    if dnsok:
        print "Discovery was successful!"
    elif not options.unattended:
        print "\nThe failure to use DNS to find your IPA server indicates that your"
        print "resolv.conf file is not properly configured.\n"
        print "Autodiscovery of servers for failover cannot work with this configuration.\n"
        print "If you proceed with the installation, services will be configured to always"
        print "access the discovered server for all operation and will not fail over to"
        print "other servers in case of failure.\n"
        if not user_input("Do you want to proceed and configure the system with fixed values with no DNS discovery?", False):
            return ret

    if options.realm_name and options.realm_name != ds.getRealmName():
        if not options.unattended:
            print "ERROR: The provided realm name: ["+options.realm_name+"] does not match with the discovered one: ["+ds.getRealmName()+"]\n"
        return -3

    cli_realm = ds.getRealmName()
    cli_basedn = ds.getBaseDN()

    print "Realm: "+cli_realm
    print "DNS Domain: "+cli_domain
    print "IPA Server: "+cli_server
    print "BaseDN: "+cli_basedn

    print "\n"
    if not options.unattended and not user_input("Continue to configure the system with these values?", False):
        return 1

    if not options.unattended:
        if options.principal is None and options.password is None and options.prompt_password is False:
            options.principal = user_input("Principal", allow_empty=False)

    if not options.on_master:
        # First test out the kerberos configuration
        try:
            (krb_fd, krb_name) = tempfile.mkstemp()
            os.close(krb_fd)
            if configure_krb5_conf(fstore, cli_basedn, cli_realm, cli_domain, cli_server, dnsok, options, krb_name):
                print "Test kerberos configuration failed"
                return 1
            os.environ['KRB5_CONFIG'] = krb_name
            join_args = ["/usr/sbin/ipa-join", "-s", cli_server]
            if options.debug:
                join_args.append("-d")
            if options.principal is not None:
                principal = options.principal
                if principal.find('@') == -1:
                    principal = '%s@%s' % (principal, cli_realm)
                print "Password for %s: " % principal,
                sys.stdout.flush()
                (stderr, stdout, returncode) = run(["/usr/kerberos/bin/kinit", principal], raiseonerr=False)
                print ""
                if returncode != 0:
                    print stdout
                    return 1
            elif options.password:
                join_args.append("-w")
                join_args.append(options.password)
            elif options.prompt_password:
                password = getpass.getpass("Password: ")
                join_args.append("-w")
                join_args.append(password)

            # Now join the domain
            (stdout, stderr, returncode) = run(join_args, raiseonerr=False)

            if returncode != 0:
                print "Joining realm failed: %s" % stderr,
                if not options.force:
                    return 1
                print "  Use ipa-getkeytab to obtain a host principal for this server."
        finally:
            if options.principal is not None:
                (stderr, stdout, returncode) = run(["/usr/kerberos/bin/kdestroy"], raiseonerr=False)
            del os.environ['KRB5_CONFIG']
            os.remove(krb_name)
            os.remove(krb_name + ".ipabkp")

    # Configure ipa.conf
    if not options.on_master:
        configure_ipa_conf(fstore, cli_basedn, cli_realm, cli_domain, cli_server)
        print "Created /etc/ipa/default.conf"

    if options.sssd:
        if configure_sssd_conf(fstore, cli_domain, cli_server, options):
            return 1
        print "Configured /etc/sssd/sssd.conf"
    else:
        if configure_ldap_conf(fstore, cli_basedn, cli_realm, cli_domain, cli_server, dnsok, options):
            return 1
        if configure_nslcd_conf(fstore, cli_basedn, cli_realm, cli_domain, cli_server, dnsok, options):
            return 1
        print "Configured LDAP"

    if not options.on_master:
        configure_certmonger(fstore, options)

    # If on master assume kerberos is already configured properly.
    if not options.on_master:
        # Configure krb5.conf
        fstore.backup_file("/etc/krb5.conf")
        if configure_krb5_conf(fstore, cli_basedn, cli_realm, cli_domain, cli_server, dnsok, options, "/etc/krb5.conf"):
            return 1

        print "Configured /etc/krb5.conf for IPA realm " + cli_realm

    # Modify nsswitch/pam stack
    if options.sssd:
        run(["/usr/sbin/authconfig", "--enablesssd", "--enablesssdauth", "--update"])
        print "SSSD enabled"
    else:
        run(["/usr/sbin/authconfig", "--enableldap", "--update"])
        print "LDAP enabled"

    #Check nss_ldap is working properly
    if not options.on_master:
        try:
            run(["getent", "passwd", "admin"])
        except Exception, e:
            print "nss_ldap is not able to use DNS discovery!"
            print "Changing configuration to use hardcoded server name: " +cli_server

            try:
                hardcode_ldap_server(cli_server)
            except Exception, e:
                print "Adding hardcoded server name to /etc/ldap.conf failed: " + str(e)
                return 1

    #Modify pam to add pam_krb5
    run(["/usr/sbin/authconfig", "--enablekrb5", "--update"])
    print "Kerberos 5 enabled"

    if options.conf_ntp and not options.on_master:
        if options.ntp_server:
            ntp_server = options.ntp_server
        else:
            ntp_server = cli_server
        ipaclient.ntpconf.config_ntp(ntp_server, fstore)
        print "NTP enabled"

    #Activate Name Server Caching Daemon
    try:
        run(["/sbin/service", "nscd", "restart"])
    except:
        print "Failed to start the NSCD daemon"
        print "Caching of users/groups will not be available"
        pass

    try:
        run(["/sbin/chkconfig", "nscd", "on"])
    except:
        print "Failed to configure automatic startup of the NSCD daemon"
        print "Caching of users/groups will not be available after reboot"
        pass

    # Get the CA certificate
    run(["/usr/bin/wget", "-O", "/etc/ipa/ca.crt", "http://%s/ipa/config/ca.crt" % cli_server])

    print "Client configuration complete."

    return 0

try:
    if __name__ == "__main__":
        sys.exit(main())
except SystemExit, e:
    sys.exit(e)
except KeyboardInterrupt:
    sys.exit(1)
