summaryrefslogtreecommitdiff
path: root/source4/scripting/bin/samba_upgradedns
blob: 5d294a14c3b453d35f67990be669beb7b3558006 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
#!/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
import shlex

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,
    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:
        slist = shlex.split(rdata.to_text())
        rec = TXTRecord(slist, 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)
    else:
        logger.info("DNS accounts already exist")

    # 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

    # Create DNS partitions if missing and fill DNS information
    try:
        expression = '(|(dnsRoot=DomainDnsZones.%s)(dnsRoot=ForestDnsZones.%s))' % \
                     (dnsdomain, dnsdomain)
        msg = ldbs.sam.search(base=names.configdn, scope=ldb.SCOPE_DEFAULT,
                              expression=expression, attrs=['nCName'])
        ncname = msg[0]['nCName'][0]
    except Exception, e:
        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)
    else:
        logger.info("DNS partitions already exist")

    # 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("Adding dns-%s account" % hostname)

        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)
    else:
        logger.info("dns-%s account already exists" % hostname)

    # Special stuff for DLZ backend
    if opts.dns_backend == "BIND9_DLZ":
        # This forces a re-creation of dns directory and all the files within
        # It's an overkill, but it's easier to re-create a samdb copy, rather
        # than trying to fix a broken copy.
        create_dns_dir(logger, paths)

        # 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")