#! /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 logging, tempfile, shutil, os, pwd
import traceback
from ConfigParser import SafeConfigParser
import krbV
from optparse import OptionParser

from ipapython import ipautil
from ipaserver.install import bindinstance, dsinstance, installutils, certs
from ipaserver.install.bindinstance import add_zone, add_reverse_zone, add_rr, add_ptr_rr
from ipaserver.install.replication import check_replication_plugin, enable_replication_version_checking
from ipaserver.plugins.ldap2 import ldap2
from ipapython import version
from ipalib import api, errors, util

def parse_options():
    usage = "%prog [options] FQDN (e.g. replica.example.com)"
    parser = OptionParser(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",
                      help="Add A and PTR records of the future replica")
    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 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 options.ip_address:
        if not installutils.verify_ip_address(options.ip_address):
            parser.error("Bad IP address")
            sys.exit(1)

    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:
        logging.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):
        logging.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("/var/kerberos/krb5kdc/ldappwd", dir + "/ldappwd")
        shutil.copy("/var/kerberos/krb5kdc/kpasswd.keytab", dir + "/kpasswd.keytab")
        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():
    if not check_replication_plugin():
        sys.exit(1)
    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

    try:
        installutils.verify_fqdn(replica_fqdn)
    except RuntimeError, e:
        msg = str(e)
        if msg.startswith('Unable to resolve host name'):
            if options.ip_address is None:
                if bindinstance.dns_container_exists(api.env.host,
                    api.env.basedn):
                    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 bindinstance.dns_container_exists(api.env.host, api.env.basedn):
            print "You can't add a DNS record because DNS is not set up."
            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 not options.ip_address:
        try:
            api.Command['dns_resolve'](replica_fqdn.decode('utf-8'))
        except errors.NotFound:
            sys.exit("Neither an A nor AAAA record for host '%s' does not exist in DNS.\nUse the --ip-address option to add DNS entries for the replica." % replica_fqdn)

    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))

    # get the directory manager password
    dirman_password = options.password
    if not options.password:
        try:
            dirman_password = get_dirman_password()
        except KeyboardInterrupt:
            sys.exit(0)

    # 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)

    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)

        zone = add_zone(domain, nsaddr=options.ip_address)
        add_rr(zone, name, "A", options.ip_address)
        add_reverse_zone(options.ip_address)
        add_ptr_rr(options.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 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
    logging.debug(message)
    print message
    sys.exit(1)