#! /usr/bin/python -E
# Authors: 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/>.
#

import sys

import tempfile, shutil, os, pwd
from ipapython.ipa_log_manager import *
import traceback
from ConfigParser import SafeConfigParser
import krbV

from ipapython import ipautil
from ipaserver.install import bindinstance, dsinstance, installutils, certs
from ipaserver.install.bindinstance import add_zone, add_reverse_zone, add_fwd_rr, add_ptr_rr, dns_container_exists
from ipaserver.install.replication import enable_replication_version_checking
from ipaserver.install.installutils import resolve_host, BadHostError, HostLookupError
from ipaserver.plugins.ldap2 import ldap2
from ipapython import version
from ipapython.config import IPAOptionParser
from ipalib import api, errors, util

def parse_options():
    usage = "%prog [options] FQDN (e.g. replica.example.com)"
    parser = IPAOptionParser(usage=usage, version=version.VERSION)

    parser.add_option("--dirsrv_pkcs12", dest="dirsrv_pkcs12",
                      help="install certificate for the directory server")
    parser.add_option("--http_pkcs12", dest="http_pkcs12",
                      help="install certificate for the http server")
    parser.add_option("--pkinit_pkcs12", dest="pkinit_pkcs12",
                      help="install certificate for the KDC")
    parser.add_option("--dirsrv_pin", dest="dirsrv_pin",
                      help="PIN for the Directory Server PKCS#12 file")
    parser.add_option("--http_pin", dest="http_pin",
                      help="PIN for the Apache Server PKCS#12 file")
    parser.add_option("--pkinit_pin", dest="pkinit_pin",
                      help="PIN for the KDC pkinit PKCS#12 file")
    parser.add_option("-p", "--password", dest="password",
                      help="Directory Manager (existing master) password")
    parser.add_option("--ip-address", dest="ip_address",
                      type="ip", help="Add A and PTR records of the future replica")
    parser.add_option("--reverse-zone", dest="reverse_zone",
                      help="The reverse DNS zone to use")
    parser.add_option("--no-reverse", dest="no_reverse", action="store_true",
                      default=False, help="Do not create reverse DNS zone")
    parser.add_option("--ca", dest="ca_file", default="/root/cacert.p12",
                      help="Location of CA PKCS#12 file, default /root/cacert.p12")
    parser.add_option("--no-pkinit", dest="setup_pkinit", action="store_false",
                      default=True, help="disables pkinit setup steps")

    options, args = parser.parse_args()

    if not options.ip_address:
        if options.reverse_zone:
            parser.error("You cannot specify a --reverse-zone option without the --ip-address option")
        if options.no_reverse:
            parser.error("You cannot specify a --no-reverse option without the --ip-address option")
    elif options.reverse_zone and options.no_reverse:
        parser.error("You cannot specify a --reverse-zone option together with --no-reverse")

    # If any of the PKCS#12 options are selected, all are required. Create a
    # list of the options and count it to enforce that all are required without
    # having a huge set of it blocks.
    if options.setup_pkinit:
        pkcs12 = [options.dirsrv_pkcs12, options.dirsrv_pin,
                  options.http_pkcs12, options.http_pin,
                  options.pkinit_pkcs12, options.pkinit_pin]
        num = 6
    else:
        pkcs12 = [options.dirsrv_pkcs12, options.dirsrv_pin,
                  options.http_pkcs12, options.http_pin]
        num = 4
    cnt = pkcs12.count(None)
    if cnt > 0 and cnt < num:
        parser.error("All PKCS#12 options are required if any are used.")

    if len(args) != 1:
        parser.error("must provide the fully-qualified name of the replica")

    return options, args

def get_subject_base(host_name, dm_password, suffix):
    try:
        conn = ldap2(shared_instance=False, base_dn=suffix)
        conn.connect(bind_dn='cn=directory manager', bind_pw=dm_password)
    except errors.ExecutionError, e:
        root_logger.critical("Could not connect to the Directory Server on %s" % host_name)
        raise e
    (dn, entry_attrs) = conn.get_ipa_config()
    conn.disconnect()
    return entry_attrs.get('ipacertificatesubjectbase', [None])[0]

def check_ipa_configuration(realm_name):
    config_dir = dsinstance.config_dirname(dsinstance.realm_to_serverid(realm_name))
    if not ipautil.dir_exists(config_dir):
        root_logger.error("could not find directory instance: %s" % config_dir)
        sys.exit(1)

def export_certdb(realm_name, ds_dir, dir, passwd_fname, fname, hostname, subject_base=None, is_kdc=False):
    """realm is the kerberos realm for the IPA server.
       ds_dir is the location of the master DS we are creating a replica for.
       dir is the location of the files for the replica we are creating.
       passwd_fname is the file containing the PKCS#12 password
       fname is the filename of the PKCS#12 file for this cert (minus the .p12).
       hostname is the FQDN of the server we're creating a cert for.

       The subject is handled by certs.CertDB:create_server_cert()
    """

    if is_kdc:
        nickname = "KDC-Cert"
    else:
        nickname = "Server-Cert"

    try:
        self_signed = certs.ipa_self_signed()

        db = certs.CertDB(realm_name, nssdir=dir, subject_base=subject_base)
        db.create_passwd_file()
        ca_db = certs.CertDB(realm_name, host_name=api.env.host, subject_base=subject_base)
        if is_kdc:
            ca_db.create_kdc_cert("KDC-Cert", hostname, dir)
        else:
            db.create_from_cacert(ca_db.cacert_fname)
            db.create_server_cert(nickname, hostname, ca_db)
    except Exception, e:
        raise e

    pkcs12_fname = dir + "/" + fname + ".p12"

    try:
        if is_kdc:
            ca_db.export_pem_p12(pkcs12_fname, passwd_fname,
                                 nickname, dir + "/kdc.pem")
        else:
            db.export_pkcs12(pkcs12_fname, passwd_fname, nickname)
    except ipautil.CalledProcessError, e:
        print "error exporting Server certificate: " + str(e)
        remove_file(pkcs12_fname)
        remove_file(passwd_fname)

    remove_file(dir + "/cert8.db")
    remove_file(dir + "/key3.db")
    remove_file(dir + "/secmod.db")
    remove_file(dir + "/noise.txt")
    if is_kdc:
        remove_file(dir + "/kdc.pem")
    if ipautil.file_exists(passwd_fname + ".orig"):
        remove_file(passwd_fname + ".orig")

def export_ra_pkcs12(dir, dm_password):
    """
       dir is the location of the files for the replica we are creating.
       dm_password is the Directory Manager password

       If this install is using dogtag/RHCS then export the RA certificate.
    """
    if certs.ipa_self_signed():
        return

    (agent_fd, agent_name) = tempfile.mkstemp()
    os.write(agent_fd, dm_password)
    os.close(agent_fd)

    try:
        try:
            db = certs.CertDB(api.env.realm, host_name=api.env.host)

            if db.has_nickname("ipaCert"):
                pkcs12_fname = "%s/ra.p12" % dir
                db.export_pkcs12(pkcs12_fname, agent_name, "ipaCert")
        except Exception, e:
            raise e
    finally:
        os.remove(agent_name)

def save_config(dir, realm_name, host_name,
                domain_name, dest_host,
                subject_base):
    config = SafeConfigParser()
    config.add_section("realm")
    config.set("realm", "realm_name", realm_name)
    config.set("realm", "master_host_name", host_name)
    config.set("realm", "domain_name", domain_name)
    config.set("realm", "destination_host", dest_host)
    config.set("realm", "subject_base", subject_base)
    fd = open(dir + "/realm_info", "w")
    config.write(fd)

def remove_file(fname, ignore_errors=True):
    try:
        os.remove(fname)
    except OSError, e:
        if not ignore_errors:
            raise e

def copy_files(realm_name, dir):
    config_dir = dsinstance.config_dirname(dsinstance.realm_to_serverid(realm_name))

    try:
        shutil.copy("/usr/share/ipa/html/ca.crt", dir + "/ca.crt")
        if ipautil.file_exists("/usr/share/ipa/html/preferences.html"):
            shutil.copy("/usr/share/ipa/html/preferences.html", dir + "/preferences.html")
            shutil.copy("/usr/share/ipa/html/configure.jar", dir + "/configure.jar")
        if ipautil.file_exists("/var/kerberos/krb5kdc/cacert.pem"):
            shutil.copy("/var/kerberos/krb5kdc/cacert.pem", dir + "/cacert.pem")
    except Exception, e:
        print "error copying files: " + str(e)
        sys.exit(1)

def get_dirman_password():
    return installutils.read_password("Directory Manager (existing master)", confirm=False, validate=False)

def main():
    installutils.check_server_configuration()
    options, args = parse_options()

    replica_fqdn = args[0]

    # Just initialize the environment. This is so the installer can have
    # access to the plugin environment
    api.bootstrap(in_server=True)
    api.finalize()

    #Automatically disable pkinit w/ dogtag until that is supported
    #[certs.ipa_self_signed() must be called only after api.finalize()]
    if not options.pkinit_pkcs12 and not certs.ipa_self_signed():
        options.setup_pkinit = False

    if certs.ipa_self_signed_master() == False:
        sys.exit('A selfsign CA backend can only prepare on the original master')

    # get the directory manager password
    dirman_password = options.password
    if not options.password:
        try:
            dirman_password = get_dirman_password()
        except KeyboardInterrupt:
            sys.exit(0)
        if dirman_password is None:
            sys.exit("\nDirectory Manager password required")

    # Try out the password
    try:
        conn = ldap2(shared_instance=False)
        conn.connect(bind_dn='cn=directory manager', bind_pw=dirman_password)
        conn.disconnect()
    except errors.ACIError:
        sys.exit("\nThe password provided is incorrect for LDAP server %s" % api.env.host)
    except errors.LDAPError:
        sys.exit("\nUnable to connect to LDAP server %s" % api.env.host)

    try:
        installutils.verify_fqdn(replica_fqdn, local_hostname=False)
    except BadHostError, e:
        msg = str(e)
        if isinstance(e, HostLookupError):
            if options.ip_address is None:
                if dns_container_exists(api.env.host, api.env.basedn,
                                        dm_password=dirman_password,
                                        ldapi=True, realm=api.env.realm):
                    msg += '\nAdd the --ip-address argument to create a DNS entry.'
                sys.exit(msg)
            else:
                # The host doesn't exist in DNS but we're adding it.
                pass
        else:
            sys.exit(msg)

    if options.ip_address:
        if not dns_container_exists(api.env.host, api.env.basedn,
                                    dm_password=dirman_password,
                                    ldapi=True, realm=api.env.realm):
            print "You can't add a DNS record because DNS is not set up."
            sys.exit(1)
        if options.reverse_zone and not bindinstance.verify_reverse_zone(options.reverse_zone, options.ip_address):
            sys.exit(1)

    if not certs.ipa_self_signed() and not ipautil.file_exists("/var/lib/pki-ca/conf/CS.cfg") and not options.dirsrv_pin:
        sys.exit("The replica must be created on the primary IPA server.\nIf you installed IPA with your own certificates using PKCS#12 files you must provide PKCS#12 files for any replicas you create as well.")

    check_ipa_configuration(api.env.realm)

    if api.env.host == replica_fqdn:
        print "You can't create a replica on itself"
        sys.exit(1)
    ds_dir = dsinstance.config_dirname(dsinstance.realm_to_serverid(api.env.realm))

    print "Preparing replica for %s from %s" % (replica_fqdn, api.env.host)
    enable_replication_version_checking(api.env.host, api.env.realm,
        dirman_password)

    subject_base = get_subject_base(api.env.host, dirman_password, util.realm_to_suffix(api.env.realm))

    top_dir = tempfile.mkdtemp("ipa")
    dir = top_dir + "/realm_info"
    os.mkdir(dir, 0700)

    if options.dirsrv_pin:
        passwd = options.dirsrv_pin
    else:
        passwd = ""

    passwd_fname = dir + "/dirsrv_pin.txt"
    fd = open(passwd_fname, "w")
    fd.write("%s\n" % passwd)
    fd.close()

    if options.dirsrv_pkcs12:
        print "Copying SSL certificate for the Directory Server from %s" % options.dirsrv_pkcs12
        try:
            shutil.copy(options.dirsrv_pkcs12, dir + "/dscert.p12")
        except IOError, e:
            print "Copy failed %s" %  e
            sys.exit(1)
    else:
        try:
            if not certs.ipa_self_signed():
                # FIXME, need option for location of CA backup
                if ipautil.file_exists(options.ca_file):
                    shutil.copy(options.ca_file, dir + "/cacert.p12")
                else:
                    raise RuntimeError("Root CA PKCS#12 not found in %s" % options.ca_file)
        except IOError, e:
            print "Copy failed %s" %  e
            sys.exit(1)
        print "Creating SSL certificate for the Directory Server"
        try:
            export_certdb(api.env.realm, ds_dir, dir, passwd_fname, "dscert", replica_fqdn, subject_base)
        except errors.CertificateOperationError, e:
            print "%s" % e
            sys.exit(1)

    if not certs.ipa_self_signed():
        print "Creating SSL certificate for the dogtag Directory Server"
        try:
            export_certdb(api.env.realm, ds_dir, dir, passwd_fname, "dogtagcert", replica_fqdn, subject_base)
        except errors.CertificateOperationError, e:
            print "%s" % e
            sys.exit(1)

    if options.http_pin:
        passwd = options.http_pin
    else:
        passwd = ""

    passwd_fname = dir + "/http_pin.txt"
    fd = open(passwd_fname, "w")
    fd.write("%s\n" % passwd)
    fd.close()

    if options.http_pkcs12:
        print "Copying SSL certificate for the Web Server from %s" % options.http_pkcs12
        try:
            shutil.copy(options.http_pkcs12, dir + "/httpcert.p12")
        except IOError, e:
            print "Copy failed %s" %  e
            sys.exit(1)
    else:
        print "Creating SSL certificate for the Web Server"
        try:
            export_certdb(api.env.realm, ds_dir, dir, passwd_fname, "httpcert", replica_fqdn, subject_base)
        except errors.CertificateOperationError, e:
            print "%s" % e
            sys.exit(1)
        print "Exporting RA certificate"
        export_ra_pkcs12(dir, dirman_password)

    if options.setup_pkinit:
        if options.pkinit_pin:
            passwd = options.pkinit_pin
        else:
            passwd = ""

        passwd_fname = dir + "/pkinit_pin.txt"
        fd = open(passwd_fname, "w")
        fd.write("%s\n" % passwd)
        fd.close()

        if options.pkinit_pkcs12:
            print "Copying SSL certificate for the KDC from %s" % options.pkinit_pkcs12
            try:
                shutil.copy(options.pkinit_pkcs12, dir + "/pkinitcert.p12")
            except IOError, e:
                print "Copy failed %s" %  e
                sys.exit(1)
        else:
            print "Creating SSL certificate for the KDC"
            try:
                export_certdb(api.env.realm, ds_dir, dir,
                              passwd_fname, "pkinitcert",
                              replica_fqdn, subject_base,
                              is_kdc=True)
            except errors.CertificateOperationError, e:
                print "%s" % e
                sys.exit(1)

    print "Copying additional files"
    copy_files(api.env.realm, dir)
    print "Finalizing configuration"
    save_config(dir, api.env.realm, api.env.host, api.env.domain, replica_fqdn, subject_base)

    replicafile = "/var/lib/ipa/replica-info-" + replica_fqdn
    encfile = replicafile+".gpg"

    print "Packaging replica information into %s" % encfile
    ipautil.run(["/bin/tar", "cf", replicafile, "-C", top_dir, "realm_info"])
    ipautil.encrypt_file(replicafile, encfile, dirman_password, top_dir);

    remove_file(replicafile)
    shutil.rmtree(dir)

    if options.ip_address:
        print "Adding DNS records for %s" % replica_fqdn
        api.Backend.ldap2.connect(bind_dn="cn=Directory Manager", bind_pw=dirman_password)

        domain = replica_fqdn.split(".")
        name = domain.pop(0)
        domain = ".".join(domain)

        ip = options.ip_address
        ip_address = str(ip)

        if options.reverse_zone:
            reverse_zone = bindinstance.normalize_zone(options.reverse_zone)
        else:
            reverse_zone = bindinstance.find_reverse_zone(ip)
            if reverse_zone is None and not options.no_reverse:
                reverse_zone = bindinstance.get_reverse_zone_default(ip)

        add_zone(domain)
        add_fwd_rr(domain, name, ip_address)

        if reverse_zone is not None:
            print "Using reverse zone %s" % reverse_zone
            add_reverse_zone(reverse_zone)
            add_ptr_rr(reverse_zone, ip_address, replica_fqdn)

try:
    if not os.geteuid()==0:
        sys.exit("\nYou must be root to run this script.\n")

    main()
except SystemExit, e:
    sys.exit(e)
except RuntimeError, e:
    sys.exit(e)
except Exception, e:
    print "preparation of replica failed: %s" % str(e)
    message = str(e)
    for str in traceback.format_tb(sys.exc_info()[2]):
        message = message + "\n" + str
    root_logger.debug(message)
    print message
    sys.exit(1)