#! /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, 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/>.
#

VERSION = "%prog .1"

import sys
import os
import string
import shutil
import socket
import logging
from optparse import OptionParser
import ipachangeconf
import ldap
from ldap import LDAPError

class ipaserver:

    def __init__(self, server):
        self.server = server
        self.realm = None
        self.domain = None
        self.basedn = None

    def getServerName(self):
        return str(self.server)

    def getDomainName(self):
        return str(self.domain)

    def getRealmName(self):
        return str(self.realm)

    def getBaseDN(self):
        return str(self.basedn)

    def check(self):
    
        lret = []
        lres = []
        lattr = ""
        linfo = ""
        lrealms = []
    
        i = 0
    
        #now verify the server is really an IPA server
        try:
            logging.debug("Init ldap with: ldap://"+self.server+":389")
            lh = ldap.initialize("ldap://"+self.server+":389")
            lh.simple_bind_s("","")
    
            logging.debug("Search rootdse")
            lret = lh.search_s("", ldap.SCOPE_BASE, "(objectClass=*)")
            for lattr in lret[0][1]:
                if lattr.lower() == "namingcontexts":
                    self.basedn = lret[0][1][lattr][0]
    
            logging.debug("Search for (info=*) in "+self.basedn+"(base)")
            lret = lh.search_s(self.basedn, ldap.SCOPE_BASE, "(info=IPA*)")
            if not lret:
                return False
            logging.debug("Found: "+str(lret))
    
            for lattr in lret[0][1]:
                if lattr.lower() == "info":
                    linfo = lret[0][1][lattr][0].lower()
                    break
    
            if not linfo:
                return False
    
            #search and return known realms
            logging.debug("Search for (objectClass=krbRealmContainer) in "+self.basedn+"(sub)")
            lret = lh.search_s("cn=kerberos,"+self.basedn, ldap.SCOPE_SUBTREE, "(objectClass=krbRealmContainer)")
            if not lret:
                #something very wrong
                return False
            logging.debug("Found: "+str(lret))
    
            for lres in lret:
                for lattr in lres[1]:
                    if lattr.lower() == "cn":
                        lrealms.append(lres[1][lattr][0])
    
    
            if len(lrealms) != 1:
                #which one? we can't attach to a multi-realm server without DNS working
                return False
            else:
                self.realm = lrealms[0]
                self.domain = lrealms[0].lower()
                return True
    
        except LDAPError, err:
            #no good
            logging.error("Ldap Error: "+str(err))
            return False

ntp_conf = """# Permit time synchronization with our time source, but do not
# permit the source to query or modify the service on this system.
restrict default kod nomodify notrap nopeer noquery
restrict -6 default kod nomodify notrap nopeer noquery

# Permit all access over the loopback interface.  This could
# be tightened as well, but to do so would effect some of
# the administrative functions.
restrict 127.0.0.1 
restrict -6 ::1

# Hosts on local network are less restricted.
#restrict 192.168.1.0 mask 255.255.255.0 nomodify notrap

# Use public servers from the pool.ntp.org project.
# Please consider joining the pool (http://www.pool.ntp.org/join.html).
server $SERVER

#broadcast 192.168.1.255 key 42		# broadcast server
#broadcastclient			# broadcast client
#broadcast 224.0.1.1 key 42		# multicast server
#multicastclient 224.0.1.1		# multicast client
#manycastserver 239.255.254.254		# manycast server
#manycastclient 239.255.254.254 key 42	# manycast client

# Undisciplined Local Clock. This is a fake driver intended for backup
# and when no outside source of synchronized time is available. 
server	127.127.1.0	# local clock
#fudge	127.127.1.0 stratum 10	

# Drift file.  Put this in a directory which the daemon can write to.
# No symbolic links allowed, either, since the daemon updates the file
# by creating a temporary in the same directory and then rename()'ing
# it to the file.
driftfile /var/lib/ntp/drift

# Key file containing the keys and key identifiers used when operating
# with symmetric key cryptography. 
keys /etc/ntp/keys

# Specify the key identifiers which are trusted.
#trustedkey 4 8 42

# Specify the key identifier to use with the ntpdc utility.
#requestkey 8

# Specify the key identifier to use with the ntpq utility.
#controlkey 8
"""

ntp_sysconfig = """# Drop root to id 'ntp:ntp' by default.
OPTIONS="-x -u ntp:ntp -p /var/run/ntpd.pid"

# Set to 'yes' to sync hw clock after successful ntpdate
SYNC_HWCLOCK=yes

# Additional options for ntpdate
NTPDATE_OPTIONS=""
"""

def config_ntp(server_fqdn):

    nc = string.replace(ntp_conf, "$SERVER", server_fqdn)

    shutil.copy("/etc/ntp.conf", "/etc/ntp.conf.ipasave")

    fd = open("/etc/ntp.conf", "w")
    fd.write(nc)
    fd.close()

    shutil.copy("/etc/sysconfig/ntpd", "/etc/sysconfig/ntpd.ipasave")

    fd = open("/etc/sysconfig/ntpd", "w")
    fd.write(ntp_sysconfig)
    fd.close()

    # Set the ntpd to start on boot
    os.system("/sbin/chkconfig ntpd on")

    # Restart ntpd
    os.system("/sbin/service ntpd restart")

def parse_options():
    parser = OptionParser(version=VERSION)
    parser.add_option("--server", dest="server", help="IPA server")
    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("-N", "--no-ntp", action="store_false",
                      help="do not configure ntp", default=True, dest="conf_ntp")

    options, args = parser.parse_args()
    if not options.server:
        parser.error("must provide an IPA server name with --server")

    return options

def ask_for_confirmation(message):
    yesno = raw_input(message + " [y/N]: ")
    if not yesno or yesno.lower()[0] != "y":
        return False
    print "\n"
    return True

def logging_setup(options):
    # Always log everything (i.e., DEBUG) to the log
    # file.
    logger = logging.getLogger('ipa-client-setup')
    fh = logging.FileHandler('ipaclient-install.log')
    formatter = logging.Formatter('%(name)-12s: %(levelname)-8s %(message)s')
    fh.setFormatter(formatter)
    logger.addHandler(fh)
    
    # If the debug option is set, also log debug messages to the console
    if options.debug:
        logger.setLevel(logging.DEBUG)
    else:
        # Otherwise, log critical and error messages
        logger.setLevel(logging.ERROR)

    return logger

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

    ipasrv = ipaserver(options.server)

    ret = ipasrv.check()
    if ret == False:
        print "Failed to verify that ["+options.server+"] is an IPA Server, aborting!"
        return -1

    print "IPA Server verified."
    print "Realm: "+ipasrv.getRealmName()
    print "DNS Domain: "+ipasrv.getDomainName()
    print "IPA Server: "+ipasrv.getServerName()
    print "BaseDN: "+ipasrv.getBaseDN()

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

    # Configure ipa.conf
    ipaconf = 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':'xmlrpc_uri', 'type':'option', 'value':'https://%s/ipa/xml' % ipasrv.getServerName()},
             {'name':'realm', 'type':'option', 'value':ipasrv.getRealmName()}]

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

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

    # Configure ldap.conf
    ldapconf = 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':ipasrv.getBaseDN()},
            {'name':'empty', 'type':'empty'},
            {'name':'nss_base_passwd', 'type':'option', 'value':'cn=users,cn=accounts,'+ipasrv.getBaseDN()+'?sub'},
            {'name':'nss_base_group', 'type':'option', 'value':'cn=users,cn=accounts,'+ipasrv.getBaseDN()+'?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'},
            {'name':'uri', 'type':'option', 'value':'ldap://'+ipasrv.getServerName()},
            {'name':'empty', 'type':'empty'}]
    try:
        ldapconf.newConf("/etc/ldap.conf", opts)
    except Exception, e:
        print "Configuration failed: " + str(e)
        return 1

    if not "" == ipasrv.getRealmName():
        #Configure krb5.conf
        krbconf = 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':ipasrv.getRealmName()}]
        libopts.append({'name':'dns_lookup_realm', 'type':'option', 'value':'false'})
        libopts.append({'name':'dns_lookup_kdc', 'type':'option', 'value':'false'})
        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'})

        #[realms]
        kropts =[{'name':'kdc', 'type':'option', 'value':ipasrv.getServerName()+':88'},
                 {'name':'admin_server', 'type':'option', 'value':ipasrv.getServerName()+':749'},
                 {'name':'default_domain', 'type':'option', 'value':ipasrv.getDomainName()}]
        ropts = [{'name':ipasrv.getRealmName(), 'type':'subsection', 'value':kropts}]
        opts.append({'name':'realms', 'type':'section', 'value':ropts})
        opts.append({'name':'empty', 'type':'empty'})

        #[domain_realm]
        dropts = [{'name':'.'+ipasrv.getDomainName(), 'type':'option', 'value':ipasrv.getRealmName()},
                  {'name':ipasrv.getDomainName(), 'type':'option', 'value':ipasrv.getRealmName()}]
        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("/etc/krb5.conf", opts);

    #Modify nsswitch to add nss_ldap
    os.system("/usr/sbin/authconfig --enableldap --kickstart")

    #Modify pam to add pam_krb5
    os.system("/usr/sbin/authconfig --enablekrb5 --kickstart")

    if options.conf_ntp:
        config_ntp(ipasrv.getServerName())

    print "Client configuration complete."

    return 0

sys.exit(main())