summaryrefslogtreecommitdiff
path: root/source4/scripting/bin/samba_spnupdate
blob: 977de68bc2c35930ec86a01897e88fbe3e7f47de (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
#!/usr/bin/env python
#
# update our servicePrincipalName names from spn_update_list
#
# Copyright (C) Andrew Tridgell 2010
# Copyright (C) Matthieu Patou <mat@matws.net> 2012
#
# 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 os, sys, re

# ensure we get messages out immediately, so they get in the samba logs,
# and don't get swallowed by a timeout
os.environ['PYTHONUNBUFFERED'] = '1'

# forcing GMT avoids a problem in some timezones with kerberos. Both MIT
# heimdal can get mutual authentication errors due to the 24 second difference
# between UTC and GMT when using some zone files (eg. the PDT zone from
# the US)
os.environ["TZ"] = "GMT"

# Find right directory when running from source tree
sys.path.insert(0, "bin/python")

import samba, ldb
import optparse
from samba import Ldb
from samba import getopt as options
from samba.auth import system_session
from samba.samdb import SamDB
from samba.credentials import Credentials, DONT_USE_KERBEROS

parser = optparse.OptionParser("samba_spnupdate")
sambaopts = options.SambaOptions(parser)
parser.add_option_group(sambaopts)
parser.add_option_group(options.VersionOptions(parser))
parser.add_option("--verbose", action="store_true")

credopts = options.CredentialsOptions(parser)
parser.add_option_group(credopts)

ccachename = None

opts, args = parser.parse_args()

if len(args) != 0:
    parser.print_usage()
    sys.exit(1)

lp = sambaopts.get_loadparm()
creds = credopts.get_credentials(lp)

domain = lp.get("realm")
host = lp.get("netbios name")


# get the list of substitution vars
def get_subst_vars(samdb):
    global lp
    vars = {}

    vars['DNSDOMAIN'] = samdb.domain_dns_name()
    vars['DNSFOREST'] = samdb.forest_dns_name()
    vars['HOSTNAME']  = samdb.host_dns_name()
    vars['NETBIOSNAME'] = lp.get('netbios name').upper()
    vars['WORKGROUP'] = lp.get('workgroup')
    vars['NTDSGUID']  = samdb.get_ntds_GUID()
    res = samdb.search(base=samdb.get_default_basedn(), scope=ldb.SCOPE_BASE, attrs=["objectGUID"])
    guid = samdb.schema_format_value("objectGUID", res[0]['objectGUID'][0])
    vars['DOMAINGUID'] = guid
    return vars

try:
    private_dir = lp.get("private dir")
    secrets_path = os.path.join(private_dir, "secrets.ldb")

    secrets_db = Ldb(url=secrets_path, session_info=system_session(),
                     credentials=creds, lp=lp)
    res = secrets_db.search(base=None,
                            expression="(&(objectclass=ldapSecret)(cn=SAMDB Credentials))",
                            attrs=["samAccountName", "secret"])

    if len(res) == 1:
        credentials = Credentials()
        credentials.set_kerberos_state(DONT_USE_KERBEROS)

        if "samAccountName" in res[0]:
            credentials.set_username(res[0]["samAccountName"][0])

        if "secret" in res[0]:
            credentials.set_password(res[0]["secret"][0])

    else:
        credentials = None

    samdb = SamDB(url=lp.samdb_url(), session_info=system_session(), credentials=credentials, lp=lp)
except ldb.LdbError, (num, msg):
    print("Unable to open sam database %s : %s" % (lp.samdb_url(), msg))
    sys.exit(1)


# get the substitution dictionary
sub_vars = get_subst_vars(samdb)

# get the list of SPN entries we should have
spn_update_list = lp.private_path('spn_update_list')

file = open(spn_update_list, "r")

spn_list = []

has_forest_dns = False
has_domain_dns = False
# check if we "are DNS server"
res = samdb.search(base=samdb.get_config_basedn(),
                   expression='(objectguid=%s)' % sub_vars['NTDSGUID'],
                   attrs=["msDS-hasMasterNCs"])

basedn = str(samdb.get_default_basedn())
if len(res) == 1:
    if "msDS-hasMasterNCs" in res[0]:
        for e in res[0]["msDS-hasMasterNCs"]:
            if str(e) == "DC=DomainDnsZones,%s" % basedn:
                has_domain_dns = True
            if str(e) == "DC=ForestDnsZones,%s" % basedn:
                has_forest_dns = True


# build the spn list
for line in file:
    line = line.strip()
    if line == '' or line[0] == "#":
        continue
    if re.match(r".*/DomainDnsZones\..*", line) and not has_domain_dns:
        continue
    if re.match(r".*/ForestDnsZones\..*", line) and not has_forest_dns:
        continue
    line = samba.substitute_var(line, sub_vars)
    spn_list.append(line)

# get the current list of SPNs in our sam
res = samdb.search(base=samdb.get_default_basedn(),
                   expression='(&(objectClass=computer)(samaccountname=%s$))' % sub_vars['NETBIOSNAME'],
                   attrs=["servicePrincipalName"])
if not res or len(res) != 1:
    print("Failed to find computer object for %s$" % sub_vars['NETBIOSNAME'])
    sys.exit(1)

machine_dn = res[0]["dn"]

old_spns = []
if "servicePrincipalName" in res[0]:
    for s in res[0]["servicePrincipalName"]:
        old_spns.append(s)

if opts.verbose:
    print("Existing SPNs: %s" % old_spns)

add_list = []

# work out what needs to be added
for s in spn_list:
    in_list = False
    for s2 in old_spns:
        if s2.upper() == s.upper():
            in_list = True
            break
    if not in_list:
        add_list.append(s)

if opts.verbose:
    print("New SPNs: %s" % add_list)

if add_list == []:
    if opts.verbose:
        print("Nothing to add")
    sys.exit(0)

def local_update(add_list):
    '''store locally'''
    global res
    msg = ldb.Message()
    msg.dn = res[0]['dn']
    msg[""] = ldb.MessageElement(add_list,
                                 ldb.FLAG_MOD_ADD, "servicePrincipalName")
    res = samdb.modify(msg)

def call_rodc_update(d):
    '''RODCs need to use the writeSPN DRS call'''
    global lp, sub_vars
    from samba import drs_utils
    from samba.dcerpc import drsuapi, nbt
    from samba.net import Net

    if opts.verbose:
        print("Using RODC SPN update")

    creds = credopts.get_credentials(lp)
    creds.set_machine_account(lp)

    net = Net(creds=creds, lp=lp)
    try:
        cldap_ret = net.finddc(domain=domain, flags=nbt.NBT_SERVER_DS | nbt.NBT_SERVER_WRITABLE)
    except Exception, reason:
        print("Unable to find writeable DC for domain '%s' to send DRS writeSPN to : %s" % (domain, reason))
        sys.exit(1)
    server = cldap_ret.pdc_dns_name
    try:
        binding_options = "seal"
        if int(lp.get("log level")) >= 5:
            binding_options += ",print"
        drs = drsuapi.drsuapi('ncacn_ip_tcp:%s[%s]' % (server, binding_options), lp, creds)
        (drs_handle, supported_extensions) = drs_utils.drs_DsBind(drs)
    except Exception, reason:
        print("Unable to connect to DC '%s' for domain '%s' : %s" % (server, domain, reason))
        sys.exit(1)
    req1 = drsuapi.DsWriteAccountSpnRequest1()
    req1.operation = drsuapi.DRSUAPI_DS_SPN_OPERATION_ADD
    req1.object_dn = str(machine_dn)
    req1.count = 0
    spn_names = []
    for n in add_list:
        if n.find('E3514235-4B06-11D1-AB04-00C04FC2DCD2') != -1:
            # this one isn't allowed for RODCs, but we don't know why yet
            continue
        ns = drsuapi.DsNameString()
        ns.str = n
        spn_names.append(ns)
        req1.count = req1.count + 1
    if spn_names == []:
        return
    req1.spn_names = spn_names
    (level, res) = drs.DsWriteAccountSpn(drs_handle, 1, req1)
    if (res.status != (0, 'WERR_OK')):
        print "WriteAccountSpn has failed with error %s" % str(res.status)

if samdb.am_rodc():
    call_rodc_update(add_list)
else:
    local_update(add_list)