upgradedns: Upgrade DNS provision from BIND9_FLATFILE to AD based DNS

This script can be used to convert provision from BIND9_FLATFILE to
BIND9_DLZ or SAMBA_INTERNAL dns backends. In addition, the script
migrates the DNS data in zone file (if available).

Autobuild-User: Amitay Isaacs <amitay@samba.org>
Autobuild-Date: Tue Feb 21 14:50:10 CET 2012 on sn-devel-104

3 files changed, 411 insertions, 2 deletions

diff --git a/source4/scripting/bin/upgradedns b/source4/scripting/bin/upgradedns
new file mode 100755
index 0000000000..234bfe84a3
--- /dev/null
+++ b/source4/scripting/bin/upgradedns
@@ -0,0 +1,404 @@
+#!/usr/bin/env python
+#
+# Unix SMB/CIFS implementation.
+# Copyright (C) Amitay Isaacs <amitay@gmail.com> 2012
+#
+# Upgrade DNS provision from BIND9_FLATFILE to BIND9_DLZ or SAMBA_INTERNAL
+#
+# 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 os
+import optparse
+import logging
+import grp
+from base64 import b64encode
+
+sys.path.insert(0, 'bin/python')
+
+import ldb
+import samba
+from samba import param
+from samba.auth import system_session
+from samba.ndr import (
+    ndr_pack,
+    ndr_unpack )
+import samba.getopt as options
+from samba.upgradehelpers import (
+    get_paths,
+    get_ldbs )
+from samba.dsdb import DS_DOMAIN_FUNCTION_2003
+from samba.provision import (
+    find_provision_key_parameters,
+    interface_ips_v4,
+    interface_ips_v6 )
+from samba.provision.common import (
+    setup_path,
+    setup_add_ldif )
+from samba.provision.sambadns import (
+    ARecord,
+    AAAARecord,
+    CNameRecord,
+    NSRecord,
+    SOARecord,
+    SRVRecord,
+    TXTRecord,
+    get_dnsadmins_sid,
+    get_domainguid,
+    add_dns_accounts,
+    create_dns_partitions,
+    fill_dns_data_partitions,
+    create_dns_dir,
+    secretsdb_setup_dns,
+    create_samdb_copy,
+    create_named_conf,
+    create_named_txt )
+from samba.dcerpc import security
+
+samba.ensure_external_module("dns", "dnspython")
+import dns.zone, dns.rdatatype
+
+__docformat__ = 'restructuredText'
+
+
+def find_bind_gid():
+    """Find system group id for bind9
+    """
+    for name in ["bind", "named"]:
+        try:
+            return grp.getgrnam(name)[2]
+        except KeyError:
+            pass
+    return None
+
+
+def fix_names(pnames):
+    """Convert elements to strings from MessageElement
+    """
+    names = pnames
+    names.rootdn = pnames.rootdn[0]
+    names.domaindn = pnames.domaindn[0]
+    names.configdn = pnames.configdn[0]
+    names.schemadn = pnames.schemadn[0]
+    names.wheel_gid = pnames.wheel_gid[0]
+    names.serverdn = str(pnames.serverdn)
+    return names
+
+
+def convert_dns_rdata(rdata, serial=1):
+    """Convert resource records in dnsRecord format
+    """
+    if rdata.rdtype == dns.rdatatype.A:
+        rec = ARecord(rdata.address, serial=serial)
+    elif rdata.rdtype == dns.rdatatype.AAAA:
+        rec = AAAARecord(rdata.address, serial=serial)
+    elif rdata.rdtype == dns.rdatatype.CNAME:
+        rec = CNameRecord(rdata.target.to_text(), serial=serial)
+    elif rdata.rdtype == dns.rdatatype.NS:
+        rec = NSRecord(rdata.target.to_text(), serial=serial)
+    elif rdata.rdtype == dns.rdatatype.SRV:
+        rec = SRVRecord(rdata.target.to_text(), int(rdata.port),
+                        priority=int(rdata.priority), weight=int(rdata.weight),
+                        serial=serial)
+    elif rdata.rdtype == dns.rdatatype.TXT:
+        rec = TXTRecord(rdata.to_text(relativize=False), serial=serial)
+    elif rdata.rdtype == dns.rdatatype.SOA:
+        rec = SOARecord(rdata.mname.to_text(), rdata.rname.to_text(),
+                        serial=int(rdata.serial),
+                        refresh=int(rdata.refresh), retry=int(rdata.retry),
+                        expire=int(rdata.expire), minimum=int(rdata.minimum))
+    else:
+        rec = None
+    return rec
+
+
+def import_zone_data(samdb, logger, zone, serial, domaindn, forestdn,
+                     dnsdomain, dnsforest):
+    """Insert zone data in DNS partitions
+    """
+    labels = dnsdomain.split('.')
+    labels.append('')
+    domain_root = dns.name.Name(labels)
+    domain_prefix = "DC=%s,CN=MicrosoftDNS,DC=DomainDnsZones,%s" % (dnsdomain,
+                                                                    domaindn)
+
+    tmp = "_msdcs.%s" % dnsforest
+    labels = tmp.split('.')
+    labels.append('')
+    forest_root = dns.name.Name(labels)
+    dnsmsdcs = "_msdcs.%s" % dnsforest
+    forest_prefix = "DC=%s,CN=MicrosoftDNS,DC=ForestDnsZones,%s" % (dnsmsdcs,
+                                                                    forestdn)
+
+    # Extract @ record
+    at_record = zone.get_node(domain_root)
+    zone.delete_node(domain_root)
+
+    # SOA record
+    rdset = at_record.get_rdataset(dns.rdataclass.IN, dns.rdatatype.SOA)
+    soa_rec = ndr_pack(convert_dns_rdata(rdset[0]))
+    at_record.delete_rdataset(dns.rdataclass.IN, dns.rdatatype.SOA)
+
+    # NS record
+    rdset = at_record.get_rdataset(dns.rdataclass.IN, dns.rdatatype.NS)
+    ns_rec = ndr_pack(convert_dns_rdata(rdset[0]))
+    at_record.delete_rdataset(dns.rdataclass.IN, dns.rdatatype.NS)
+
+    # A/AAAA records
+    ip_recs = []
+    for rdset in at_record:
+        for r in rdset:
+            rec = convert_dns_rdata(r)
+            ip_recs.append(ndr_pack(rec))
+
+    # Add @ record for domain
+    dns_rec = [soa_rec, ns_rec] + ip_recs
+    msg = ldb.Message(ldb.Dn(samdb, 'DC=@,%s' % domain_prefix))
+    msg["objectClass"] = ["top", "dnsNode"]
+    msg["dnsRecord"] = ldb.MessageElement(dns_rec, ldb.FLAG_MOD_ADD,
+                                          "dnsRecord")
+    try:
+        samdb.add(msg)
+    except Exception:
+        logger.error("Failed to add @ record for domain")
+        raise
+    logger.debug("Added @ record for domain")
+
+    # Add @ record for forest
+    dns_rec = [soa_rec, ns_rec]
+    msg = ldb.Message(ldb.Dn(samdb, 'DC=@,%s' % forest_prefix))
+    msg["objectClass"] = ["top", "dnsNode"]
+    msg["dnsRecord"] = ldb.MessageElement(dns_rec, ldb.FLAG_MOD_ADD,
+                                          "dnsRecord")
+    try:
+        samdb.add(msg)
+    except Exception:
+        logger.error("Failed to add @ record for forest")
+        raise
+    logger.debug("Added @ record for forest")
+
+    # Add remaining records in domain and forest
+    for node in zone.nodes:
+        name = node.relativize(forest_root).to_text()
+        if name == node.to_text():
+            name = node.relativize(domain_root).to_text()
+            dn = "DC=%s,%s" % (name, domain_prefix)
+            fqdn = "%s.%s" % (name, dnsdomain)
+        else:
+            dn = "DC=%s,%s" % (name, forest_prefix)
+            fqdn = "%s.%s" % (name, dnsmsdcs)
+
+        dns_rec = []
+        for rdataset in zone.nodes[node]:
+            for rdata in rdataset:
+                rec = convert_dns_rdata(rdata, serial)
+                if not rec:
+                    logger.warn("Unsupported record type (%s) for %s, ignoring" %
+                                dns.rdatatype.to_text(rdata.rdatatype), name)
+                else:
+                    dns_rec.append(ndr_pack(rec))
+
+        msg = ldb.Message(ldb.Dn(samdb, dn))
+        msg["objectClass"] = ["top", "dnsNode"]
+        msg["dnsRecord"] = ldb.MessageElement(dns_rec, ldb.FLAG_MOD_ADD,
+                                              "dnsRecord")
+        try:
+            samdb.add(msg)
+        except Exception:
+            logger.error("Failed to add DNS record %s" % (fqdn))
+            raise
+        logger.debug("Added DNS record %s" % (fqdn))
+
+
+# dnsprovision creates application partitions for AD based DNS mainly if the existing
+# provision was created using earlier snapshots of samba4 which did not have support
+# for DNS partitions
+
+if __name__ == '__main__':
+
+    # Setup command line parser
+    parser = optparse.OptionParser("upgradedns [options]")
+    sambaopts = options.SambaOptions(parser)
+    credopts = options.CredentialsOptions(parser)
+
+    parser.add_option_group(options.VersionOptions(parser))
+    parser.add_option_group(sambaopts)
+    parser.add_option_group(credopts)
+
+    parser.add_option("--dns-backend", type="choice", metavar="<BIND9_DLZ|SAMBA_INTERNAL>",
+                      choices=["SAMBA_INTERNAL", "BIND9_DLZ"], default="BIND9_DLZ",
+                      help="The DNS server backend, default BIND9_DLZ")
+    parser.add_option("--migrate", type="choice", metavar="<yes|no>",
+                      choices=["yes","no"], default="yes",
+                      help="Migrate existing zone data, default yes")
+    parser.add_option("--verbose", help="Be verbose", action="store_true")
+
+    opts = parser.parse_args()[0]
+
+    if opts.dns_backend is None:
+        opts.dns_backend = 'DLZ_BIND9'
+
+    if opts.migrate:
+        autofill = False
+    else:
+        autofill = True
+
+    # Set up logger
+    logger = logging.getLogger("upgradedns")
+    logger.addHandler(logging.StreamHandler(sys.stdout))
+    logger.setLevel(logging.INFO)
+    if opts.verbose:
+        logger.setLevel(logging.DEBUG)
+
+    lp = sambaopts.get_loadparm()
+    lp.load(lp.configfile)
+    creds = credopts.get_credentials(lp)
+
+    logger.info("Reading domain information")
+    paths = get_paths(param, smbconf=lp.configfile)
+    paths.bind_gid = find_bind_gid()
+    ldbs = get_ldbs(paths, creds, system_session(), lp)
+    pnames = find_provision_key_parameters(ldbs.sam, ldbs.secrets, ldbs.idmap,
+                                           paths, lp.configfile, lp)
+    names = fix_names(pnames)
+
+    if names.domainlevel < DS_DOMAIN_FUNCTION_2003:
+        logger.error("Cannot create AD based DNS for OS level < 2003")
+        sys.exit(1)
+
+    logger.info("Looking up IPv4 addresses")
+    hostip = interface_ips_v4(lp)
+    try:
+        hostip.remove('127.0.0.1')
+    except ValueError:
+        pass
+    if not hostip:
+        logger.error("No IPv4 addresses found")
+        sys.exit(1)
+    else:
+        hostip = hostip[0]
+        logger.debug("IPv4 addresses: %s" % hostip)
+
+    logger.info("Looking up IPv6 addresses")
+    hostip6 = interface_ips_v6(lp, linklocal=False)
+    if not hostip6:
+        hostip6 = None
+    else:
+        hostip6 = hostip6[0]
+        logger.debug("IPv6 addresses: %s" % hostip6)
+
+    domaindn = names.domaindn
+    forestdn = names.rootdn
+
+    dnsdomain = names.dnsdomain.lower()
+    dnsforest = dnsdomain
+
+    site = names.sitename
+    hostname = names.hostname
+    dnsname = '%s.%s' % (hostname, dnsdomain)
+
+    domainsid = names.domainsid
+    domainguid = names.domainguid
+    ntdsguid = names.ntdsguid
+
+    # Check for DNS accounts and create them if required
+    try:
+        msg = ldbs.sam.search(base=domaindn, scope=ldb.SCOPE_DEFAULT,
+                              expression='(sAMAccountName=DnsAdmins)',
+                              attrs=['objectSid'])
+        dnsadmins_sid = ndr_unpack(security.dom_sid, msg[0]['objectSid'][0])
+    except Exception, e:
+        logger.info("Adding DNS accounts")
+        add_dns_accounts(ldbs.sam, domaindn)
+        dnsadmins_sid = get_dnsadmins_sid(ldbs.sam, domaindn)
+
+    # Import dns records from zone file
+    if os.path.exists(paths.dns):
+        logger.info("Reading records from zone file %s" % paths.dns)
+        try:
+            zone = dns.zone.from_file(paths.dns, relativize=False)
+            rrset = zone.get_rdataset("%s." % dnsdomain, dns.rdatatype.SOA)
+            serial = int(rrset[0].serial)
+        except Exception, e:
+            logger.warn("Error parsing DNS data from '%s' (%s)" % (paths.dns, str(e)))
+            logger.warn("DNS records will be automatically created")
+            autofill = True
+    else:
+        logger.info("No zone file %s" % paths.dns)
+        logger.warn("DNS records will be automatically created")
+        autofill = True
+
+    # Fill DNS information
+    logger.info("Creating DNS partitions")
+    create_dns_partitions(ldbs.sam, domainsid, names, domaindn, forestdn,
+                          dnsadmins_sid)
+
+    logger.info("Populating DNS partitions")
+    fill_dns_data_partitions(ldbs.sam, domainsid, site, domaindn, forestdn,
+                             dnsdomain, dnsforest, hostname, hostip, hostip6,
+                             domainguid, ntdsguid, dnsadmins_sid,
+                             autofill=autofill)
+
+    if not autofill:
+        logger.info("Importing records from zone file")
+        import_zone_data(ldbs.sam, logger, zone, serial, domaindn, forestdn,
+                         dnsdomain, dnsforest)
+
+    if opts.dns_backend == "BIND9_DLZ":
+        create_dns_dir(logger, paths)
+
+        # Check if dns-HOSTNAME account exists and create it if required
+        try:
+            dn = 'samAccountName=dns-%s,CN=Principals' % hostname
+            msg = ldbs.secrets.search(expression='(dn=%s)' % dn, attrs=['secret'])
+            dnssecret = msg[0]['secret'][0]
+        except Exception:
+            logger.info("Creating DNS account for BIND9")
+
+            try:
+                msg = ldbs.sam.search(base=domaindn, scope=ldb.SCOPE_DEFAULT,
+                                      expression='(sAMAccountName=dns-%s)' % (hostname),
+                                      attrs=['clearTextPassword'])
+                dn = msg[0].dn
+                ldbs.sam.delete(dn)
+            except Exception:
+                pass
+
+            dnspass = samba.generate_random_password(128, 255)
+            setup_add_ldif(ldbs.sam, setup_path("provision_dns_add_samba.ldif"), {
+                           "DNSDOMAIN": dnsdomain,
+                           "DOMAINDN": domaindn,
+                           "DNSPASS_B64": b64encode(dnspass.encode('utf-16-le')),
+                           "HOSTNAME" : hostname,
+                           "DNSNAME" : dnsname }
+                           )
+
+            secretsdb_setup_dns(ldbs.secrets, names,
+                                paths.private_dir, realm=names.realm,
+                                dnsdomain=names.dnsdomain,
+                                dns_keytab_path=paths.dns_keytab, dnspass=dnspass)
+
+        # Setup a copy of SAM for BIND9
+        create_samdb_copy(ldbs.sam, logger, paths, names, domainsid,
+                          domainguid)
+
+        create_named_conf(paths, names.realm, dnsdomain, opts.dns_backend)
+
+        create_named_txt(paths.namedtxt, names.realm, dnsdomain, dnsname,
+                         paths.private_dir, paths.dns_keytab)
+        logger.info("See %s for an example configuration include file for BIND", paths.namedconf)
+        logger.info("and %s for further documentation required for secure DNS "
+                    "updates", paths.namedtxt)
+
+    logger.info("Finished upgrading DNS")
diff --git a/source4/scripting/bin/wscript_build b/source4/scripting/bin/wscript_build
index ad83894c8c..65e9c58b69 100644
--- a/source4/scripting/bin/wscript_build
+++ b/source4/scripting/bin/wscript_build
@@ -5,3 +5,4 @@ bld.SAMBA_SCRIPT('samba_spnupdate', pattern='samba_spnupdate', installdir='.')
 bld.SAMBA_SCRIPT('samba_kcc', pattern='samba_kcc', installdir='.')
 bld.SAMBA_SCRIPT('upgradeprovision', pattern='upgradeprovision', installdir='.')
 bld.SAMBA_SCRIPT('samba-tool', pattern='samba-tool', installdir='.')
+bld.SAMBA_SCRIPT('upgradedns', pattern='upgradedns', installdir='.')
diff --git a/source4/scripting/wscript_build b/source4/scripting/wscript_build
index 9e2cb1eff8..e8d52d5cb6 100644
--- a/source4/scripting/wscript_build
+++ b/source4/scripting/wscript_build
@@ -2,8 +2,12 @@
 
 from samba_utils import MODE_755
 
-bld.INSTALL_FILES('${SBINDIR}', 'bin/upgradeprovision bin/samba_dnsupdate bin/samba_spnupdate',
+bld.INSTALL_FILES('${SBINDIR}',
+                  'bin/upgradeprovision bin/samba_dnsupdate bin/samba_spnupdate bin/upgradedns',
+                  chmod=MODE_755, python_fixup=True, flat=True)
+
+bld.INSTALL_FILES('${BINDIR}',
+                  'bin/samba-tool bin/samba_kcc',
                   chmod=MODE_755, python_fixup=True, flat=True)
-bld.INSTALL_FILES('${BINDIR}', 'bin/samba-tool bin/samba_kcc', chmod=MODE_755, python_fixup=True, flat=True)
 
 bld.RECURSE('bin')