-#!/usr/bin/env python
+#!/usr/bin/env python3
+# vim: expandtab
#
# update our DNS names using TSIG-GSS
#
# and don't get swallowed by a timeout
os.environ['PYTHONUNBUFFERED'] = '1'
-# forcing GMT avoids a problem in some timezones with kerberos. Both MIT
+# forcing GMT avoids a problem in some timezones with kerberos. Both MIT and
# 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)
import optparse
from samba import getopt as options
from ldb import SCOPE_BASE
+from samba import dsdb
from samba.auth import system_session
from samba.samdb import SamDB
from samba.dcerpc import netlogon, winbind
+from samba.netcmd.dns import cmd_dns
+from samba import gensec
+from samba.kcc import kcc_utils
+from samba.common import get_string
+import ldb
-samba.ensure_external_module("dns", "dnspython")
+from samba.dnsresolver import DNSResolver
import dns.resolver
import dns.exception
am_rodc = False
error_count = 0
-parser = optparse.OptionParser("samba_dnsupdate")
+parser = optparse.OptionParser("samba_dnsupdate [options]")
sambaopts = options.SambaOptions(parser)
parser.add_option_group(sambaopts)
parser.add_option_group(options.VersionOptions(parser))
parser.add_option("--verbose", action="store_true")
+parser.add_option("--use-samba-tool", action="store_true", help="Use samba-tool to make updates over RPC, rather than over DNS")
+parser.add_option("--use-nsupdate", action="store_true", help="Use nsupdate command to make updates over DNS (default, if kinit successful)")
parser.add_option("--all-names", action="store_true")
parser.add_option("--all-interfaces", action="store_true")
+parser.add_option("--current-ip", action="append", help="IP address to update DNS to match (helpful if behind NAT, valid multiple times, defaults to values from interfaces=)")
+parser.add_option("--rpc-server-ip", type="string", help="IP address of server to use with samba-tool (defaults to first --current-ip)")
parser.add_option("--use-file", type="string", help="Use a file, rather than real DNS calls")
parser.add_option("--update-list", type="string", help="Add DNS names from the given file")
+parser.add_option("--update-cache", type="string", help="Cache database of already registered records")
parser.add_option("--fail-immediately", action='store_true', help="Exit on first failure")
parser.add_option("--no-credentials", dest='nocreds', action='store_true', help="don't try and get credentials")
+parser.add_option("--no-substitutions", dest='nosubs', action='store_true', help="don't try and expands variables in file specified by --update-list")
creds = None
ccachename = None
domain = lp.get("realm")
host = lp.get("netbios name")
-if opts.all_interfaces:
- all_interfaces = True
-else:
- all_interfaces = False
+all_interfaces = opts.all_interfaces
+
+IPs = opts.current_ip or samba.interface_ips(lp, bool(all_interfaces)) or []
-IPs = samba.interface_ips(lp, all_interfaces)
nsupdate_cmd = lp.get('nsupdate command')
+dns_zone_scavenging = lp.get("dns zone scavenging")
if len(IPs) == 0:
- print "No IP interfaces - skipping DNS updates"
+ print("No IP interfaces - skipping DNS updates\n")
+ parser.print_usage()
sys.exit(0)
-IP6s = []
-IP4s = []
-for i in IPs:
- if i.find(':') != -1:
- if i.find('%') == -1:
- # we don't want link local addresses for DNS updates
- IP6s.append(i)
- else:
- IP4s.append(i)
+rpc_server_ip = opts.rpc_server_ip or IPs[0]
+
+IP6s = [ip for ip in IPs if ':' in ip]
+IP4s = [ip for ip in IPs if ':' not in ip]
+smb_conf = sambaopts.get_loadparm_path()
if opts.verbose:
- print "IPs: %s" % IPs
+ print("IPs: %s" % IPs)
+
+def get_possible_rw_dns_server(creds, domain):
+ """Get a list of possible read-write DNS servers, starting with
+ the SOA. The SOA is the correct answer, but old Samba domains
+ (4.6 and prior) do not maintain this value, so add NS servers
+ as well"""
+
+ ans_soa = check_one_dns_name(domain, 'SOA')
+ # Actually there is only one
+ hosts_soa = [str(a.mname).rstrip('.') for a in ans_soa]
+
+ # This is not strictly legit, but old Samba domains may have an
+ # unmaintained SOA record, so go for any NS that we can get a
+ # ticket to.
+ ans_ns = check_one_dns_name(domain, 'NS')
+ # Actually there is only one
+ hosts_ns = [str(a.target).rstrip('.') for a in ans_ns]
+
+ return hosts_soa + hosts_ns
+
+def get_krb5_rw_dns_server(creds, domain):
+ """Get a list of read-write DNS servers that we can obtain a ticket
+ to, starting with the SOA. The SOA is the correct answer, but
+ old Samba domains (4.6 and prior) do not maintain this value,
+ so continue with the NS servers as well until we get one that
+ the KDC will issue a ticket to.
+ """
+
+ rw_dns_servers = get_possible_rw_dns_server(creds, domain)
+ # Actually there is only one
+ for i, target_hostname in enumerate(rw_dns_servers):
+ settings = {}
+ settings["lp_ctx"] = lp
+ settings["target_hostname"] = target_hostname
+
+ gensec_client = gensec.Security.start_client(settings)
+ gensec_client.set_credentials(creds)
+ gensec_client.set_target_service("DNS")
+ gensec_client.set_target_hostname(target_hostname)
+ gensec_client.want_feature(gensec.FEATURE_SEAL)
+ gensec_client.start_mech_by_sasl_name("GSSAPI")
+ server_to_client = b""
+ try:
+ (client_finished, client_to_server) = gensec_client.update(server_to_client)
+ if opts.verbose:
+ print("Successfully obtained Kerberos ticket to DNS/%s as %s" \
+ % (target_hostname, creds.get_username()))
+ return target_hostname
+ except RuntimeError:
+ # Only raise an exception if they all failed
+ if i == len(rw_dns_servers) - 1:
+ raise
-########################################################
-# get credentials if we haven't got them already
def get_credentials(lp):
+ """# get credentials if we haven't got them already."""
from samba import credentials
- global ccachename, creds
- if creds is not None:
- return
+ global ccachename
creds = credentials.Credentials()
creds.guess(lp)
creds.set_machine_account(lp)
creds.set_krb_forwardable(credentials.NO_KRB_FORWARDABLE)
(tmp_fd, ccachename) = tempfile.mkstemp()
- creds.get_named_ccache(lp, ccachename)
+ try:
+ if opts.use_file is not None:
+ return
+
+ creds.get_named_ccache(lp, ccachename)
+
+ # Now confirm we can get a ticket to the DNS server
+ get_krb5_rw_dns_server(creds, sub_vars['DNSDOMAIN'] + '.')
+ return creds
+
+ except RuntimeError as e:
+ os.unlink(ccachename)
+ raise e
-#############################################
-# an object to hold a parsed DNS line
class dnsobj(object):
+ """an object to hold a parsed DNS line"""
+
def __init__(self, string_form):
list = string_form.split()
+ if len(list) < 3:
+ raise Exception("Invalid DNS entry %r" % string_form)
self.dest = None
self.port = None
self.ip = None
self.existing_port = None
self.existing_weight = None
+ self.existing_cname_target = None
+ self.rpc = False
+ self.zone = None
+ if list[0] == "RPC":
+ self.rpc = True
+ self.zone = list[1]
+ list = list[2:]
self.type = list[0]
- self.name = list[1].lower()
+ self.name = list[1]
+ self.nameservers = []
if self.type == 'SRV':
- self.dest = list[2].lower()
+ if len(list) < 4:
+ raise Exception("Invalid DNS entry %r" % string_form)
+ self.dest = list[2]
self.port = list[3]
elif self.type in ['A', 'AAAA']:
self.ip = list[2] # usually $IP, which gets replaced
elif self.type == 'CNAME':
- self.dest = list[2].lower()
+ self.dest = list[2]
elif self.type == 'NS':
- self.dest = list[2].lower()
+ self.dest = list[2]
else:
- print "Received unexpected DNS reply of type %s" % self.type
- raise
+ raise Exception("Received unexpected DNS reply of type %s: %s" % (self.type, string_form))
def __str__(self):
- if d.type == "A": return "%s %s %s" % (self.type, self.name, self.ip)
- if d.type == "AAAA": return "%s %s %s" % (self.type, self.name, self.ip)
- if d.type == "SRV": return "%s %s %s %s" % (self.type, self.name, self.dest, self.port)
- if d.type == "CNAME": return "%s %s %s" % (self.type, self.name, self.dest)
- if d.type == "NS": return "%s %s %s" % (self.type, self.name, self.dest)
+ if self.type == "A":
+ return "%s %s %s" % (self.type, self.name, self.ip)
+ if self.type == "AAAA":
+ return "%s %s %s" % (self.type, self.name, self.ip)
+ if self.type == "SRV":
+ return "%s %s %s %s" % (self.type, self.name, self.dest, self.port)
+ if self.type == "CNAME":
+ return "%s %s %s" % (self.type, self.name, self.dest)
+ if self.type == "NS":
+ return "%s %s %s" % (self.type, self.name, self.dest)
-################################################
-# parse a DNS line from
def parse_dns_line(line, sub_vars):
+ """parse a DNS line from."""
if line.startswith("SRV _ldap._tcp.pdc._msdcs.") and not samdb.am_pdc():
+ # We keep this as compat to the dns_update_list of 4.0/4.1
if opts.verbose:
- print "Skipping PDC entry (%s) as we are not a PDC" % line
+ print("Skipping PDC entry (%s) as we are not a PDC" % line)
return None
subline = samba.substitute_var(line, sub_vars)
- d = dnsobj(subline)
- return d
+ if subline == '' or subline[0] == "#":
+ return None
+ return dnsobj(subline)
+
-############################################
-# see if two hostnames match
def hostname_match(h1, h2):
+ """see if two hostnames match."""
h1 = str(h1)
h2 = str(h2)
return h1.lower().rstrip('.') == h2.lower().rstrip('.')
+def get_resolver(d=None):
+ resolv_conf = os.getenv('RESOLV_CONF', default='/etc/resolv.conf')
+ resolver = DNSResolver(filename=resolv_conf, configure=True)
+
+ if d is not None and d.nameservers != []:
+ resolver.nameservers = d.nameservers
+
+ return resolver
+
+def check_one_dns_name(name, name_type, d=None):
+ resolver = get_resolver(d)
+ if d and not d.nameservers:
+ d.nameservers = resolver.nameservers
+ # dns.resolver.Answer
+ return resolver.resolve(name, name_type)
-############################################
-# check that a DNS entry exists
def check_dns_name(d):
+ """check that a DNS entry exists."""
normalised_name = d.name.rstrip('.') + '.'
if opts.verbose:
- print "Looking for DNS entry %s as %s" % (d, normalised_name)
-
+ print("Looking for DNS entry %s as %s" % (d, normalised_name))
+
if opts.use_file is not None:
try:
dns_file = open(opts.use_file, "r")
except IOError:
return False
-
- for line in dns_file:
- line = line.strip()
- if line == '' or line[0] == "#":
- continue
- if line.lower() == str(d).lower():
- return True
- return False
- resolver = dns.resolver.Resolver()
- if d.type == "NS":
- # we need to lookup the nameserver for the parent domain,
- # and use that to check the NS record
- parent_domain = '.'.join(normalised_name.split('.')[1:])
- try:
- ans = resolver.query(parent_domain, 'NS')
- except dns.exception.DNSException:
- if opts.verbose:
- print "Failed to find parent NS for %s" % d
- return False
- nameservers = set()
- for i in range(len(ans)):
- try:
- ns = resolver.query(str(ans[i]), 'A')
- except dns.exception.DNSException:
- continue
- for j in range(len(ns)):
- nameservers.add(str(ns[j]))
- d.nameservers = list(nameservers)
+ with dns_file:
+ for line in dns_file:
+ line = line.strip()
+ if line == '' or line[0] == "#":
+ continue
+ if line.lower() == str(d).lower():
+ return True
+ return False
try:
- if getattr(d, 'nameservers', None):
- resolver.nameservers = list(d.nameservers)
- ans = resolver.query(normalised_name, d.type)
- except dns.exception.DNSException:
+ ans = check_one_dns_name(normalised_name, d.type, d)
+ except dns.exception.Timeout:
+ raise Exception("Timeout while waiting to contact a working DNS server while looking for %s as %s" % (d, normalised_name))
+ except dns.resolver.NoNameservers:
+ raise Exception("Unable to contact a working DNS server while looking for %s as %s" % (d, normalised_name))
+ except dns.resolver.NXDOMAIN:
+ if opts.verbose:
+ print("The DNS entry %s, queried as %s does not exist" % (d, normalised_name))
+ return False
+ except dns.resolver.NoAnswer:
if opts.verbose:
- print "Failed to find DNS entry %s" % d
+ print("The DNS entry %s, queried as %s does not hold this record type" % (d, normalised_name))
return False
+ except dns.exception.DNSException:
+ raise Exception("Failure while trying to resolve %s as %s" % (d, normalised_name))
if d.type in ['A', 'AAAA']:
# we need to be sure that our IP is there
for rdata in ans:
if str(rdata) == str(d.ip):
return True
- if d.type == 'CNAME':
+ elif d.type == 'CNAME':
for i in range(len(ans)):
if hostname_match(ans[i].target, d.dest):
return True
- if d.type == 'NS':
+ else:
+ d.existing_cname_target = str(ans[i].target)
+ elif d.type == 'NS':
for i in range(len(ans)):
if hostname_match(ans[i].target, d.dest):
return True
- if d.type == 'SRV':
+ elif d.type == 'SRV':
for rdata in ans:
if opts.verbose:
- print "Checking %s against %s" % (rdata, d)
+ print("Checking %s against %s" % (rdata, d))
if hostname_match(rdata.target, d.dest):
if str(rdata.port) == str(d.port):
return True
d.existing_weight = str(rdata.weight)
if opts.verbose:
- print "Failed to find matching DNS entry %s" % d
+ print("Lookup of %s succeeded, but we failed to find a matching DNS entry for %s" % (normalised_name, d))
return False
-###########################################
-# get the list of substitution vars
def get_subst_vars(samdb):
+ """get the list of substitution vars."""
global lp, am_rodc
vars = {}
vars['SITE'] = samdb.server_site_name()
res = samdb.search(base=samdb.get_default_basedn(), scope=SCOPE_BASE, attrs=["objectGUID"])
guid = samdb.schema_format_value("objectGUID", res[0]['objectGUID'][0])
- vars['DOMAINGUID'] = guid
+ vars['DOMAINGUID'] = get_string(guid)
+
+ vars['IF_DC'] = ""
+ vars['IF_RWDC'] = "# "
+ vars['IF_RODC'] = "# "
+ vars['IF_PDC'] = "# "
+ vars['IF_GC'] = "# "
+ vars['IF_RWGC'] = "# "
+ vars['IF_ROGC'] = "# "
+ vars['IF_DNS_DOMAIN'] = "# "
+ vars['IF_RWDNS_DOMAIN'] = "# "
+ vars['IF_RODNS_DOMAIN'] = "# "
+ vars['IF_DNS_FOREST'] = "# "
+ vars['IF_RWDNS_FOREST'] = "# "
+ vars['IF_R0DNS_FOREST'] = "# "
+
am_rodc = samdb.am_rodc()
+ if am_rodc:
+ vars['IF_RODC'] = ""
+ else:
+ vars['IF_RWDC'] = ""
+
+ if samdb.am_pdc():
+ vars['IF_PDC'] = ""
+
+ # check if we "are DNS server"
+ res = samdb.search(base=samdb.get_config_basedn(),
+ expression='(objectguid=%s)' % vars['NTDSGUID'],
+ attrs=["options", "msDS-hasMasterNCs"])
+
+ if len(res) == 1:
+ if "options" in res[0]:
+ options = int(res[0]["options"][0])
+ if (options & dsdb.DS_NTDSDSA_OPT_IS_GC) != 0:
+ vars['IF_GC'] = ""
+ if am_rodc:
+ vars['IF_ROGC'] = ""
+ else:
+ vars['IF_RWGC'] = ""
+
+ basedn = str(samdb.get_default_basedn())
+ forestdn = str(samdb.get_root_basedn())
+
+ if "msDS-hasMasterNCs" in res[0]:
+ for e in res[0]["msDS-hasMasterNCs"]:
+ if str(e) == "DC=DomainDnsZones,%s" % basedn:
+ vars['IF_DNS_DOMAIN'] = ""
+ if am_rodc:
+ vars['IF_RODNS_DOMAIN'] = ""
+ else:
+ vars['IF_RWDNS_DOMAIN'] = ""
+ if str(e) == "DC=ForestDnsZones,%s" % forestdn:
+ vars['IF_DNS_FOREST'] = ""
+ if am_rodc:
+ vars['IF_RODNS_FOREST'] = ""
+ else:
+ vars['IF_RWDNS_FOREST'] = ""
return vars
-############################################
-# call nsupdate for an entry
-def call_nsupdate(d):
- global ccachename, nsupdate_cmd
+def call_nsupdate(d, op="add"):
+ """call nsupdate for an entry."""
+ global ccachename, nsupdate_cmd, krb5conf
- if opts.verbose:
- print "Calling nsupdate for %s" % d
+ assert(op in ["add", "delete"])
if opts.use_file is not None:
- wfile = open(opts.use_file, 'a')
- fcntl.lockf(wfile, fcntl.LOCK_EX)
- wfile.write(str(d)+"\n")
- fcntl.lockf(wfile, fcntl.LOCK_UN)
+ if opts.verbose:
+ print("Use File instead of nsupdate for %s (%s)" % (d, op))
+
+ try:
+ rfile = open(opts.use_file, 'r+')
+ except IOError:
+ # Perhaps create it
+ open(opts.use_file, 'w+').close()
+ # Open it for reading again, in case someone else got to it first
+ rfile = open(opts.use_file, 'r+')
+ fcntl.lockf(rfile, fcntl.LOCK_EX)
+ (file_dir, file_name) = os.path.split(opts.use_file)
+ (tmp_fd, tmpfile) = tempfile.mkstemp(dir=file_dir, prefix=file_name, suffix="XXXXXX")
+ wfile = os.fdopen(tmp_fd, 'a')
+ for line in rfile:
+ if op == "delete":
+ l = parse_dns_line(line, {})
+ if str(l).lower() == str(d).lower():
+ continue
+ wfile.write(line)
+ if op == "add":
+ wfile.write(str(d)+"\n")
+ rfile.close()
+ wfile.close()
+ os.rename(tmpfile, opts.use_file)
return
+ if opts.verbose:
+ print("Calling nsupdate for %s (%s)" % (d, op))
+
normalised_name = d.name.rstrip('.') + '.'
(tmp_fd, tmpfile) = tempfile.mkstemp()
f = os.fdopen(tmp_fd, 'w')
- if getattr(d, 'nameservers', None):
- f.write('server %s\n' % d.nameservers[0])
+
+ resolver = get_resolver(d)
+
+ # Local the zone for this name
+ zone = dns.resolver.zone_for_name(normalised_name,
+ resolver=resolver)
+
+ # Now find the SOA, or if we can't get a ticket to the SOA,
+ # any server with an NS record we can get a ticket for.
+ #
+ # Thanks to the Kerberos Credentials cache this is not
+ # expensive inside the loop
+ server = get_krb5_rw_dns_server(creds, zone)
+ f.write('server %s\n' % server)
+
if d.type == "A":
- f.write("update add %s %u A %s\n" % (normalised_name, default_ttl, d.ip))
+ f.write("update %s %s %u A %s\n" % (op, normalised_name, default_ttl, d.ip))
if d.type == "AAAA":
- f.write("update add %s %u AAAA %s\n" % (normalised_name, default_ttl, d.ip))
+ f.write("update %s %s %u AAAA %s\n" % (op, normalised_name, default_ttl, d.ip))
if d.type == "SRV":
- if d.existing_port is not None:
+ if op == "add" and d.existing_port is not None:
f.write("update delete %s SRV 0 %s %s %s\n" % (normalised_name, d.existing_weight,
d.existing_port, d.dest))
- f.write("update add %s %u SRV 0 100 %s %s\n" % (normalised_name, default_ttl, d.port, d.dest))
+ f.write("update %s %s %u SRV 0 100 %s %s\n" % (op, normalised_name, default_ttl, d.port, d.dest))
if d.type == "CNAME":
- f.write("update add %s %u CNAME %s\n" % (normalised_name, default_ttl, d.dest))
+ f.write("update %s %s %u CNAME %s\n" % (op, normalised_name, default_ttl, d.dest))
if d.type == "NS":
- f.write("update add %s %u NS %s\n" % (normalised_name, default_ttl, d.dest))
+ f.write("update %s %s %u NS %s\n" % (op, normalised_name, default_ttl, d.dest))
if opts.verbose:
f.write("show\n")
f.write("send\n")
f.close()
+ # Set a bigger MTU size to work around a bug in nsupdate's doio_send()
+ os.environ["SOCKET_WRAPPER_MTU"] = "2000"
+
global error_count
if ccachename:
os.environ["KRB5CCNAME"] = ccachename
try:
cmd = nsupdate_cmd[:]
cmd.append(tmpfile)
+ env = os.environ
+ if krb5conf:
+ env["KRB5_CONFIG"] = krb5conf
if ccachename:
- env = {"KRB5CCNAME": ccachename}
- else:
- env = {}
+ env["KRB5CCNAME"] = ccachename
ret = subprocess.call(cmd, shell=False, env=env)
if ret != 0:
if opts.fail_immediately:
error_count = error_count + 1
if opts.verbose:
print("Failed nsupdate: %d" % ret)
- except Exception, estr:
+ except Exception as estr:
if opts.fail_immediately:
sys.exit(1)
error_count = error_count + 1
print("Failed nsupdate: %s : %s" % (str(d), estr))
os.unlink(tmpfile)
+ # Let socket_wrapper set the default MTU size
+ os.environ["SOCKET_WRAPPER_MTU"] = "0"
-def rodc_dns_update(d, t):
+def call_samba_tool(d, op="add", zone=None):
+ """call samba-tool dns to update an entry."""
+
+ assert(op in ["add", "delete"])
+
+ if (sub_vars['DNSFOREST'] != sub_vars['DNSDOMAIN']) and \
+ sub_vars['DNSFOREST'].endswith('.' + sub_vars['DNSDOMAIN']):
+ print("Refusing to use samba-tool when forest %s is under domain %s" \
+ % (sub_vars['DNSFOREST'], sub_vars['DNSDOMAIN']))
+
+ if opts.verbose:
+ print("Calling samba-tool dns for %s (%s)" % (d, op))
+
+ normalised_name = d.name.rstrip('.') + '.'
+ if zone is None:
+ if normalised_name == (sub_vars['DNSDOMAIN'] + '.'):
+ short_name = '@'
+ zone = sub_vars['DNSDOMAIN']
+ elif normalised_name == (sub_vars['DNSFOREST'] + '.'):
+ short_name = '@'
+ zone = sub_vars['DNSFOREST']
+ elif normalised_name == ('_msdcs.' + sub_vars['DNSFOREST'] + '.'):
+ short_name = '@'
+ zone = '_msdcs.' + sub_vars['DNSFOREST']
+ else:
+ if not normalised_name.endswith('.' + sub_vars['DNSDOMAIN'] + '.'):
+ print("Not Calling samba-tool dns for %s (%s), %s not in %s" % (d, op, normalised_name, sub_vars['DNSDOMAIN'] + '.'))
+ return False
+ elif normalised_name.endswith('._msdcs.' + sub_vars['DNSFOREST'] + '.'):
+ zone = '_msdcs.' + sub_vars['DNSFOREST']
+ else:
+ zone = sub_vars['DNSDOMAIN']
+ len_zone = len(zone)+2
+ short_name = normalised_name[:-len_zone]
+ else:
+ len_zone = len(zone)+2
+ short_name = normalised_name[:-len_zone]
+
+ if d.type == "A":
+ args = [rpc_server_ip, zone, short_name, "A", d.ip]
+ if d.type == "AAAA":
+ args = [rpc_server_ip, zone, short_name, "AAAA", d.ip]
+ if d.type == "SRV":
+ if op == "add" and d.existing_port is not None:
+ print("Not handling modify of existing SRV %s using samba-tool" % d)
+ return False
+ args = [rpc_server_ip, zone, short_name, "SRV",
+ "%s %s %s %s" % (d.dest, d.port, "0", "100")]
+ if d.type == "CNAME":
+ if d.existing_cname_target is None:
+ args = [rpc_server_ip, zone, short_name, "CNAME", d.dest]
+ else:
+ op = "update"
+ args = [rpc_server_ip, zone, short_name, "CNAME",
+ d.existing_cname_target.rstrip('.'), d.dest]
+
+ if d.type == "NS":
+ args = [rpc_server_ip, zone, short_name, "NS", d.dest]
+
+ if smb_conf and args:
+ args += ["--configfile=" + smb_conf]
+
+ global error_count
+ try:
+ cmd = cmd_dns()
+ if opts.verbose:
+ print(f'Calling samba-tool dns {op} --use-kerberos off -P {args}')
+ command, args = cmd._resolve("dns", op, "--use-kerberos", "off", "-P", *args)
+ ret = command._run(*args)
+ if ret == -1:
+ if opts.fail_immediately:
+ sys.exit(1)
+ error_count = error_count + 1
+ if opts.verbose:
+ print("Failed 'samba-tool dns' based update of %s" % (str(d)))
+ except Exception as estr:
+ if opts.fail_immediately:
+ sys.exit(1)
+ error_count = error_count + 1
+ if opts.verbose:
+ print("Failed 'samba-tool dns' based update: %s : %s" % (str(d), estr))
+ raise
+
+irpc_wb = None
+def cached_irpc_wb(lp):
+ global irpc_wb
+ if irpc_wb is not None:
+ return irpc_wb
+ irpc_wb = winbind.winbind("irpc:winbind_server", lp)
+ return irpc_wb
+
+def rodc_dns_update(d, t, op):
'''a single DNS update via the RODC netlogon call'''
global sub_vars
+ assert(op in ["add", "delete"])
+
if opts.verbose:
- print "Calling netlogon RODC update for %s" % d
+ print("Calling netlogon RODC update for %s" % d)
typemap = {
netlogon.NlDnsLdapAtSite : netlogon.NlDnsInfoTypeNone,
netlogon.NlDnsGenericGcAtSite : netlogon.NlDnsDomainNameAlias
}
- w = winbind.winbind("irpc:winbind_server", lp)
+ w = cached_irpc_wb(lp)
dns_names = netlogon.NL_DNS_NAME_INFO_ARRAY()
dns_names.count = 1
name = netlogon.NL_DNS_NAME_INFO()
name.weight = 0
if d.port is not None:
name.port = int(d.port)
- name.dns_register = True
+ if op == "add":
+ name.dns_register = True
+ else:
+ name.dns_register = False
dns_names.names = [ name ]
- site_name = sub_vars['SITE'].decode('utf-8')
+ site_name = sub_vars['SITE']
global error_count
if ret_names.names[0].status != 0:
print("Failed to set DNS entry: %s (status %u)" % (d, ret_names.names[0].status))
error_count = error_count + 1
- except RuntimeError, reason:
+ except RuntimeError as reason:
print("Error setting DNS entry of type %u: %s: %s" % (t, d, reason))
error_count = error_count + 1
+ if opts.verbose:
+ print("Called netlogon RODC update for %s" % d)
+
if error_count != 0 and opts.fail_immediately:
sys.exit(1)
-def call_rodc_update(d):
+def call_rodc_update(d, op="add"):
'''RODCs need to use the netlogon API for nsupdate'''
global lp, sub_vars
+ assert(op in ["add", "delete"])
+
# we expect failure for 3268 if we aren't a GC
if d.port is not None and int(d.port) == 3268:
return
subname = samba.substitute_var(map[t], sub_vars)
if subname.lower() == d.name.lower():
# found a match - do the update
- rodc_dns_update(d, t)
+ rodc_dns_update(d, t, op)
return
if opts.verbose:
print("Unable to map to netlogon DNS update: %s" % d)
# get the list of DNS entries we should have
-if opts.update_list:
- dns_update_list = opts.update_list
-else:
- dns_update_list = lp.private_path('dns_update_list')
-
-# use our private krb5.conf to avoid problems with the wrong domain
-# bind9 nsupdate wants the default domain set
-krb5conf = lp.private_path('krb5.conf')
-os.environ['KRB5_CONFIG'] = krb5conf
-
-file = open(dns_update_list, "r")
+dns_update_list = opts.update_list or lp.private_path('dns_update_list')
+
+dns_update_cache = opts.update_cache or lp.private_path('dns_update_cache')
+
+krb5conf = None
+# only change the krb5.conf if we are not in selftest
+if 'SOCKET_WRAPPER_DIR' not in os.environ:
+ # use our private krb5.conf to avoid problems with the wrong domain
+ # bind9 nsupdate wants the default domain set
+ krb5conf = lp.private_path('krb5.conf')
+ os.environ['KRB5_CONFIG'] = krb5conf
+
+try:
+ file = open(dns_update_list, "r")
+except OSError as e:
+ if opts.update_list:
+ print("The specified update list does not exist")
+ else:
+ print("The server update list was not found, "
+ "and --update-list was not provided.")
+ print(e)
+ print()
+ parser.print_usage()
+ sys.exit(1)
-samdb = SamDB(url=lp.samdb_url(), session_info=system_session(),
- lp=lp)
+if opts.nosubs:
+ sub_vars = {}
+else:
+ samdb = SamDB(url=lp.samdb_url(), session_info=system_session(), lp=lp)
-# get the substitution dictionary
-sub_vars = get_subst_vars(samdb)
+ # get the substitution dictionary
+ sub_vars = get_subst_vars(samdb)
# build up a list of update commands to pass to nsupdate
update_list = []
dns_list = []
+cache_list = []
+delete_list = []
dup_set = set()
+cache_set = set()
+
+rebuild_cache = False
+try:
+ cfile = open(dns_update_cache, 'r+')
+except IOError:
+ # Perhaps create it
+ open(dns_update_cache, 'w+').close()
+ # Open it for reading again, in case someone else got to it first
+ cfile = open(dns_update_cache, 'r+')
+fcntl.lockf(cfile, fcntl.LOCK_EX)
+for line in cfile:
+ line = line.strip()
+ if line == '' or line[0] == "#":
+ continue
+ c = parse_dns_line(line, {})
+ if c is None:
+ continue
+ if str(c) not in cache_set:
+ cache_list.append(c)
+ cache_set.add(str(c))
+
+cfile.close()
+
+site_specific_rec = []
# read each line, and check that the DNS name exists
for line in file:
line = line.strip()
+
+ if '${SITE}' in line:
+ site_specific_rec.append(line)
+
if line == '' or line[0] == "#":
continue
d = parse_dns_line(line, sub_vars)
dns_list.append(d)
dup_set.add(str(d))
+file.close()
+
+# Perform automatic site coverage by default
+auto_coverage = True
+
+if not am_rodc and auto_coverage:
+ site_names = kcc_utils.uncovered_sites_to_cover(samdb,
+ samdb.server_site_name())
+
+ # Duplicate all site specific records for the uncovered site
+ for site in site_names:
+ to_add = [samba.substitute_var(line, {'SITE': site})
+ for line in site_specific_rec]
+
+ for site_line in to_add:
+ d = parse_dns_line(site_line,
+ sub_vars=sub_vars)
+ if d is not None and str(d) not in dup_set:
+ dns_list.append(d)
+ dup_set.add(str(d))
+
# now expand the entries, if any are A record with ip set to $IP
# then replace with multiple entries, one for each interface IP
for d in dns_list:
# now check if the entries already exist on the DNS server
for d in dns_list:
- if opts.all_names or not check_dns_name(d):
+ found = False
+ for c in cache_list:
+ if str(c).lower() == str(d).lower():
+ found = True
+ break
+ if not found:
+ rebuild_cache = True
+ if opts.verbose:
+ print("need cache add: %s" % d)
+ if dns_zone_scavenging:
+ update_list.append(d)
+ if opts.verbose:
+ print("scavenging requires update: %s" % d)
+ elif opts.all_names:
update_list.append(d)
+ if opts.verbose:
+ print("force update: %s" % d)
+ elif not check_dns_name(d):
+ update_list.append(d)
+ if opts.verbose:
+ print("need update: %s" % d)
+
+for c in cache_list:
+ found = False
+ for d in dns_list:
+ if str(c).lower() == str(d).lower():
+ found = True
+ break
+ if found:
+ continue
+ rebuild_cache = True
+ if opts.verbose:
+ print("need cache remove: %s" % c)
+ if not opts.all_names and not check_dns_name(c):
+ continue
+ delete_list.append(c)
+ if opts.verbose:
+ print("need delete: %s" % c)
-if len(update_list) == 0:
+if len(delete_list) == 0 and len(update_list) == 0 and not rebuild_cache:
if opts.verbose:
- print "No DNS updates needed"
+ print("No DNS updates needed")
sys.exit(0)
+else:
+ if opts.verbose:
+ print("%d DNS updates and %d DNS deletes needed" % (len(update_list), len(delete_list)))
+use_samba_tool = opts.use_samba_tool
+use_nsupdate = opts.use_nsupdate
# get our krb5 creds
-if not opts.nocreds:
- get_credentials(lp)
+if (delete_list or update_list) and not opts.nocreds:
+ try:
+ creds = get_credentials(lp)
+ except RuntimeError as e:
+ ccachename = None
+
+ if sub_vars['IF_RWDNS_DOMAIN'] == "# ":
+ raise
+
+ if use_nsupdate:
+ raise
+
+ print("Failed to get Kerberos credentials, falling back to samba-tool: %s" % e)
+ use_samba_tool = True
+
+
+# ask nsupdate to delete entries as needed
+for d in delete_list:
+ if d.rpc or (not use_nsupdate and use_samba_tool):
+ if opts.verbose:
+ print("delete (samba-tool): %s" % d)
+ call_samba_tool(d, op="delete", zone=d.zone)
+
+ elif am_rodc:
+ if d.name.lower() == domain.lower():
+ if opts.verbose:
+ print("skip delete (rodc): %s" % d)
+ continue
+ if d.type not in [ 'A', 'AAAA' ]:
+ if opts.verbose:
+ print("delete (rodc): %s" % d)
+ call_rodc_update(d, op="delete")
+ else:
+ if opts.verbose:
+ print("delete (nsupdate): %s" % d)
+ call_nsupdate(d, op="delete")
+ else:
+ if opts.verbose:
+ print("delete (nsupdate): %s" % d)
+ call_nsupdate(d, op="delete")
# ask nsupdate to add entries as needed
for d in update_list:
- if am_rodc:
+ if d.rpc or (not use_nsupdate and use_samba_tool):
+ if opts.verbose:
+ print("update (samba-tool): %s" % d)
+ call_samba_tool(d, zone=d.zone)
+
+ elif am_rodc:
if d.name.lower() == domain.lower():
+ if opts.verbose:
+ print("skip (rodc): %s" % d)
continue
- if not d.type in [ 'A', 'AAAA' ]:
+ if d.type not in [ 'A', 'AAAA' ]:
+ if opts.verbose:
+ print("update (rodc): %s" % d)
call_rodc_update(d)
else:
+ if opts.verbose:
+ print("update (nsupdate): %s" % d)
call_nsupdate(d)
else:
+ if opts.verbose:
+ print("update(nsupdate): %s" % d)
call_nsupdate(d)
+if rebuild_cache:
+ print("Rebuilding cache at %s" % dns_update_cache)
+ (file_dir, file_name) = os.path.split(dns_update_cache)
+ (tmp_fd, tmpfile) = tempfile.mkstemp(dir=file_dir, prefix=file_name, suffix="XXXXXX")
+ wfile = os.fdopen(tmp_fd, 'a')
+ for d in dns_list:
+ if opts.verbose:
+ print("Adding %s to %s" % (str(d), file_name))
+ wfile.write(str(d)+"\n")
+ wfile.close()
+ os.rename(tmpfile, dns_update_cache)
+
# delete the ccache if we created it
if ccachename is not None:
os.unlink(ccachename)