#! /usr/bin/python
#
# Authors: Sumit Bose <sbose@redhat.com>
# Based on ipa-server-install by Karl MacMillan <kmacmillan@mentalrootkit.com>
# and ipa-dns-install by Martin Nagy
#
# 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/>.
#

import traceback

from ipaserver.plugins.ldap2 import ldap2
from ipaserver.install import adtrustinstance
from ipaserver.install.installutils import *
from ipaserver.install import installutils
from ipapython import version
from ipapython import ipautil, sysrestore
from ipalib import api, errors, util
from ipapython.config import IPAOptionParser
import krbV
import ldap
from ipapython.ipa_log_manager import *

def parse_options():
    parser = IPAOptionParser(version=version.VERSION)
    parser.add_option("-p", "--ds-password", dest="dm_password",
                      sensitive=True, help="directory manager password")
    parser.add_option("-d", "--debug", dest="debug", action="store_true",
                      default=False, help="print debugging information")
    parser.add_option("--ip-address", dest="ip_address",
                      type="ip", ip_local=True, help="Master Server IP Address")
    parser.add_option("--netbios-name", dest="netbios_name",
                      help="NetBIOS name of the IPA domain")
    parser.add_option("--no-msdcs", dest="no_msdcs", action="store_true",
                      default=False, help="Do not create DNS service records " \
                                          "for Windows in managed DNS server")
    parser.add_option("-U", "--unattended", dest="unattended", action="store_true",
                      default=False, help="unattended installation never prompts the user")

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

    return safe_options, options

def netbios_name_error(name):
    print "Illegal NetBIOS name [%s].\n" % name
    print "Up to 15 characters and only uppercase ASCII letter and digits are allowed."

def read_netbios_name(netbios_default):
    netbios_name = ""

    print "Enter the NetBIOS name for the IPA domain."
    print "Only up to 15 uppercase ASCII letters and digits are allowed."
    print "Example: EXAMPLE."
    print ""
    print ""
    if not netbios_default:
        netbios_default = "EXAMPLE"
    while True:
        netbios_name = ipautil.user_input("NetBIOS domain name", netbios_default, allow_empty = False)
        print ""
        if adtrustinstance.check_netbios_name(netbios_name):
            break

        netbios_name_error(netbios_name)

    return netbios_name

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

    if os.getegid() != 0:
        sys.exit("Must be root to setup AD trusts on server")

    standard_logging_setup("/var/log/ipaserver-install.log", debug=options.debug, filemode='a')
    print "\nThe log file for this installation can be found in /var/log/ipaserver-install.log"

    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")

    installutils.check_server_configuration()

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

    print "=============================================================================="
    print "This program will setup components needed to establish trust to AD domains for"
    print "the FreeIPA Server."
    print ""
    print "This includes:"
    print "  * Configure Samba"
    print "  * Add trust related objects to FreeIPA LDAP server"
    #TODO:
    #print "  * Add a SID to all users and Posix groups"
    print ""
    print "To accept the default shown in brackets, press the Enter key."
    print ""

    # Check if samba packages are installed
    if not adtrustinstance.check_inst():
        sys.exit("Aborting installation.")

    # Initialize the ipalib api
    cfg = dict(
        in_server=True,
        debug=options.debug,
    )
    api.bootstrap(**cfg)
    api.finalize()

    if adtrustinstance.ipa_smb_conf_exists():
        if not options.unattended:
            while True:
                print "IPA generated smb.conf detected."
                if not ipautil.user_input("Overwrite smb.conf?", default = False, allow_empty = False):
                    sys.exit("Aborting installation.")
                break

    # Check we have a public IP that is associated with the hostname
    try:
        if options.ip_address:
            ip = ipautil.CheckedIPAddress(options.ip_address, match_local=True)
        else:
            hostaddr = resolve_host(api.env.host)
            ip = hostaddr and ipautil.CheckedIPAddress(hostaddr, match_local=True)
    except Exception, e:
        print "Error: Invalid IP Address %s: %s" % (ip, e)
        ip = None

    if not ip:
        if options.unattended:
            sys.exit("Unable to resolve IP address for host name")
        else:
            read_ip = read_ip_address(api.env.host, fstore)
            try:
                ip = ipautil.CheckedIPAddress(read_ip, match_local=True)
            except Exception, e:
                print "Error: Invalid IP Address %s: %s" % (ip, e)
                sys.exit("Aborting installation.")

    ip_address = str(ip)
    root_logger.debug("will use ip_address: %s\n", ip_address)

    if not options.unattended:
        print ""
        print "The following operations may take some minutes to complete."
        print "Please wait until the prompt is returned."
        print ""

    # Create a Adtrust instance
    if options.unattended and not options.dm_password:
        sys.exit("\nIn unattended mode you need to provide at least the -p option")

    netbios_name = options.netbios_name
    if not netbios_name:
        netbios_name = adtrustinstance.make_netbios_name(api.env.domain)

    if not adtrustinstance.check_netbios_name(netbios_name):
        if options.unattended:
            netbios_name_error(netbios_name)
            sys.exit("Aborting installation.")
        else:
            netbios_name = None
            if options.netbios_name:
                netbios_name_error(options.netbios_name)

    if not options.unattended and ( not netbios_name or not options.netbios_name):
        netbios_name = read_netbios_name(netbios_name)

    dm_password = options.dm_password or read_password("Directory Manager",
                                             confirm=False, validate=False)
    smb = adtrustinstance.ADTRUSTInstance(fstore, dm_password)

    # try the connection
    try:
        smb.ldap_connect()
        smb.ldap_disconnect()
    except ldap.INVALID_CREDENTIALS, e:
        sys.exit("Password is not valid!")

    if smb.dm_password:
        api.Backend.ldap2.connect(bind_dn="cn=Directory Manager", bind_pw=smb.dm_password)
    else:
        # See if our LDAP server is up and we can talk to it over GSSAPI
        ccache = krbV.default_context().default_ccache().name
        api.Backend.ldap2.connect(ccache)

    smb.setup(api.env.host, ip_address, api.env.realm, api.env.domain,
              netbios_name, options.no_msdcs)
    smb.create_instance()

    print "=============================================================================="
    print "Setup complete"
    print ""
    print "\tYou must make sure these network ports are open:"
    print "\t\tTCP Ports:"
    print "\t\t  * 138: netbios-dgm"
    print "\t\t  * 139: netbios-ssn"
    print "\t\t  * 445: microsoft-ds"
    print "\t\tUDP Ports:"
    print "\t\t  * 138: netbios-dgm"
    print "\t\t  * 139: netbios-ssn"
    print "\t\t  * 389: (C)LDAP"
    print "\t\t  * 445: microsoft-ds"
    print ""
    print "\tAdditionally you have to make sure the FreeIPA LDAP server cannot reached"
    print "\tby any domain controller in the Active Directory domain by closing the"
    print "\tfollowing ports for these servers:"
    print "\t\tTCP Ports:"
    print "\t\t  * 389, 636: LDAP/LDAPS"
    print "\tYou may want to choose to REJECT the network packets instead of DROPing them"
    print "\tto avoid timeouts on the AD domain controllers."

    return 0

try:
    sys.exit(main())
except SystemExit, e:
    sys.exit(e)
except KeyboardInterrupt:
    print "Installation cancelled."
except RuntimeError, e:
    print str(e)
except HostnameLocalhost:
    print "The hostname resolves to the localhost address (127.0.0.1/::1)"
    print "Please change your /etc/hosts file so that the hostname"
    print "resolves to the ip address of your network interface."
    print "The KDC service does not listen on localhost"
    print ""
    print "Please fix your /etc/hosts file and restart the setup program"
except Exception, e:
    message = "Unexpected error - see ipaserver-install.log for details:\n %s" % str(e)
    print message
    message = str(e)
    for str in traceback.format_tb(sys.exc_info()[2]):
        message = message + "\n" + str
    root_logger.debug(message)
    sys.exit(1)