Ensure ipa-adtrust-install is run with Kerberos ticket for admin user

When setting up AD trusts support, ipa-adtrust-install utility
needs to be run as:
   - root, for performing Samba configuration and using LDAPI/autobind
   - kinit-ed IPA admin user, to ensure proper ACIs are granted to
     fetch keytab

As result, we can get rid of Directory Manager credentials in ipa-adtrust-install

https://fedorahosted.org/freeipa/ticket/2815

install/tools/ipa-adtrust-install

@@ -24,7 +24,7 @@
 from ipaserver.plugins.ldap2 import ldap2
 from ipaserver.install import adtrustinstance
 from ipaserver.install.installutils import *
-from ipaserver.install import installutils
+from ipaserver.install import service
 from ipapython import version
 from ipapython import ipautil, sysrestore
 from ipalib import api, errors, util
@@ -37,8 +37,6 @@ log_file_name = "/var/log/ipaserver-install.log"
 
 def parse_options():
     parser = IPAOptionParser(version=version.VERSION)
-    parser.add_option("-p", "--ds-password", dest="dm_password",
-                      sensitive=True, help="directory manager password")
     parser.add_option("-d", "--debug", dest="debug", action="store_true",
                       default=False, help="print debugging information")
     parser.add_option("--ip-address", dest="ip_address",
@@ -98,7 +96,7 @@ def main():
     root_logger.debug('%s was invoked with options: %s' % (sys.argv[0], safe_options))
     root_logger.debug("missing options might be asked for interactively later\n")
 
-    installutils.check_server_configuration()
+    check_server_configuration()
 
     global fstore
     fstore = sysrestore.FileStore('/var/lib/ipa/sysrestore')
@@ -194,24 +192,34 @@ def main():
     if not options.unattended and ( not netbios_name or not options.netbios_name):
         netbios_name = read_netbios_name(netbios_name)
 
-    dm_password = options.dm_password or read_password("Directory Manager",
-                                             confirm=False, validate=False)
-    smb = adtrustinstance.ADTRUSTInstance(fstore, dm_password)
-
-    # try the connection
     try:
-        smb.ldap_connect()
+        ctx = krbV.default_context()
-        smb.ldap_disconnect()
+        ccache = ctx.default_ccache()
-    except ldap.INVALID_CREDENTIALS, e:
+        principal = ccache.principal()
-        sys.exit("Password is not valid!")
+    except krbV.Krb5Error, e:
+        sys.exit("Must have Kerberos credentials to setup AD trusts on server")
 
-    if smb.dm_password:
+    try:
-        api.Backend.ldap2.connect(bind_dn="cn=Directory Manager", bind_pw=smb.dm_password)
+        api.Backend.ldap2.connect(ccache.name)
-    else:
+    except errors.ACIError, e:
-        # See if our LDAP server is up and we can talk to it over GSSAPI
+        sys.exit("Outdated Kerberos credentials. Use kdestroy and kinit to update your ticket")
-        ccache = krbV.default_context().default_ccache().name
+    except errors.DatabaseError, e:
-        api.Backend.ldap2.connect(ccache)
+        sys.exit("Cannot connect to the LDAP database. Please check if IPA is running")
 
+    try:
+        user = api.Command.user_show(unicode(principal[0]))['result']
+        group = api.Command.group_show(u'admins')['result']
+        if not (user['uid'][0] in group['member_user'] and
+                group['cn'][0] in user['memberof_group']):
+            raise errors.RequirementError(name='admins group membership')
+    except errors.RequirementError, e:
+        sys.exit("Must have administrative privileges to setup AD trusts on server")
+    except Exception, e:
+        sys.exit("Unrecognized error during check of admin rights: %s" % (str(e)))
+
+    smb = adtrustinstance.ADTRUSTInstance(fstore)
+    smb.realm = api.env.realm
+    smb.autobind = service.ENABLED
     smb.setup(api.env.host, ip_address, api.env.realm, api.env.domain,
               netbios_name, options.rid_base, options.secondary_rid_base,
               options.no_msdcs)
@@ -250,5 +258,5 @@ information"""
     return 0
 
 if __name__ == '__main__':
-    installutils.run_script(main, log_file_name=log_file_name,
+    run_script(main, log_file_name=log_file_name,
             operation_name='ipa-adtrust-install')

install/tools/man/ipa-adtrust-install.1

@@ -27,9 +27,6 @@ trust to an Active Directory domain. This requires that the IPA server is
 already installed and configured.
 .SH "OPTIONS"
 .TP
-\fB\-p\fR \fIDM_PASSWORD\fR, \fB\-\-ds\-password\fR=\fIDM_PASSWORD\fR
-The password to be used by the Directory Server for the Directory Manager user
-.TP
 \fB\-d\fR, \fB\-\-debug\fR
 Enable debug logging when more verbose output is needed
 .TP

ipaserver/install/adtrustinstance.py

@@ -96,10 +96,9 @@ class ADTRUSTInstance(service.Service):
     OBJC_GROUP = "ipaNTGroupAttrs"
     OBJC_DOMAIN = "ipaNTDomainAttrs"
 
-    def __init__(self, fstore=None, dm_password=None):
+    def __init__(self, fstore=None):
         self.fqdn = None
         self.ip_address = None
-        self.realm_name = None
         self.domain_name = None
         self.netbios_name = None
         self.no_msdcs = None
@@ -118,7 +117,7 @@ class ADTRUSTInstance(service.Service):
         self.rid_base = None
         self.secondary_rid_base = None
 
-        service.Service.__init__(self, "smb", dm_password=dm_password)
+        service.Service.__init__(self, "smb", dm_password=None, ldapi=True)
 
         if fstore:
             self.fstore = fstore
@@ -436,6 +435,8 @@ class ADTRUSTInstance(service.Service):
         # We do not let the system start IPA components on its own,
         # Instead we reply on the IPA init script to start only enabled
         # components as found in our LDAP configuration tree
+        # Note that self.dm_password is None for ADTrustInstance because
+        # we ensure to be called as root and using ldapi to use autobind
         try:
             self.ldap_enable('ADTRUST', self.fqdn, self.dm_password, \
                              self.suffix)
@@ -449,7 +450,7 @@ class ADTRUSTInstance(service.Service):
             root_logger.info("EXTID Service startup entry already exists.")
 
     def __setup_sub_dict(self):
-        self.sub_dict = dict(REALM = self.realm_name,
+        self.sub_dict = dict(REALM = self.realm,
                              SUFFIX = self.suffix,
                              NETBIOS_NAME = self.netbios_name,
                              SMB_DN = self.smb_dn,
@@ -460,16 +461,16 @@ class ADTRUSTInstance(service.Service):
               rid_base, secondary_rid_base, no_msdcs=False, smbd_user="samba"):
         self.fqdn = fqdn
         self.ip_address = ip_address
-        self.realm_name = realm_name
+        self.realm = realm_name
         self.domain_name = domain_name
         self.netbios_name = netbios_name
         self.rid_base = rid_base
         self.secondary_rid_base = secondary_rid_base
         self.no_msdcs = no_msdcs
         self.smbd_user = smbd_user
-        self.suffix = ipautil.realm_to_suffix(self.realm_name)
+        self.suffix = ipautil.realm_to_suffix(self.realm)
         self.ldapi_socket = "%%2fvar%%2frun%%2fslapd-%s.socket" % \
-                            realm_to_serverid(self.realm_name)
+                            realm_to_serverid(self.realm)
 
         self.smb_conf = "/etc/samba/smb.conf"
 
@@ -479,7 +480,7 @@ class ADTRUSTInstance(service.Service):
         self.trust_dn = str(DN(api.env.container_trusts, self.suffix))
         self.smb_dom_dn = str(DN(('cn', self.domain_name),
                                  api.env.container_cifsdomains, self.suffix))
-        self.cifs_principal = "cifs/" + self.fqdn + "@" + self.realm_name
+        self.cifs_principal = "cifs/" + self.fqdn + "@" + self.realm
         self.cifs_agent = str(DN(('krbprincipalname', self.cifs_principal.lower()),
                                  api.env.container_service,
                                  self.suffix))
@@ -522,11 +523,11 @@ class ADTRUSTInstance(service.Service):
                              "range.\nAdd local ID range manually and try " \
                              "again!")
 
-        entry = ipaldap.Entry(str(DN(('cn', ('%s_id_range' % self.realm_name)),
+        entry = ipaldap.Entry(str(DN(('cn', ('%s_id_range' % self.realm)),
                                      api.env.container_ranges,
                                      self.suffix)))
         entry.setValue('objectclass', 'ipaDomainIDRange')
-        entry.setValue('cn', ('%s_id_range' % self.realm_name))
+        entry.setValue('cn', ('%s_id_range' % self.realm))
         entry.setValue('ipaBaseID', str(base_id))
         entry.setValue('ipaIDRangeSize', str(id_range_size))
         self.admin_conn.addEntry(entry)

ipaserver/install/bindinstance.py

@@ -448,7 +448,7 @@ class DnsBackup(object):
 
 class BindInstance(service.Service):
     def __init__(self, fstore=None, dm_password=None):
-        service.Service.__init__(self, "named", dm_password=dm_password)
+        service.Service.__init__(self, "named", dm_password=dm_password, ldapi=False, autobind=service.DISABLED)
         self.dns_backup = DnsBackup(self)
         self.named_user = None
         self.domain = None

ipaserver/install/cainstance.py

@@ -225,10 +225,9 @@ def get_outputList(data):
 
 class CADSInstance(service.Service):
     def __init__(self, host_name=None, realm_name=None, domain_name=None, dm_password=None):
-        service.Service.__init__(self, "pkids")
+        service.Service.__init__(self, "pkids", dm_password=dm_password, ldapi=False, autobind=service.DISABLED)
         self.serverid = "PKI-IPA"
         self.realm_name = realm_name
-        self.dm_password = dm_password
         self.sub_dict = None
         self.domain = domain_name
         self.fqdn = host_name

ipaserver/install/dsinstance.py

@@ -160,7 +160,7 @@ info: IPA V2.0
 
 class DsInstance(service.Service):
     def __init__(self, realm_name=None, domain_name=None, dm_password=None, fstore=None):
-        service.Service.__init__(self, "dirsrv", dm_password=dm_password)
+        service.Service.__init__(self, "dirsrv", dm_password=dm_password, ldapi=False, autobind=service.DISABLED)
         self.realm_name = realm_name
         self.sub_dict = None
         self.domain = domain_name

ipaserver/install/krbinstance.py

@@ -178,7 +178,7 @@ class KrbInstance(service.Service):
         self.start_creation("Configuring Kerberos KDC", 30)
 
         self.kpasswd = KpasswdInstance()
-        self.kpasswd.create_instance('KPASSWD', self.fqdn, self.admin_password, self.suffix)
+        self.kpasswd.create_instance('KPASSWD', self.fqdn, self.admin_password, self.suffix, realm=self.realm)
 
     def create_replica(self, realm_name,
                        master_fqdn, host_name,

ipaserver/install/service.py

@@ -35,6 +35,11 @@ from ipapython.ipa_log_manager import *
 
 CACERT = "/etc/ipa/ca.crt"
 
+# Autobind modes
+AUTO = 1
+ENABLED = 2
+DISABLED = 3
+
 # The service name as stored in cn=masters,cn=ipa,cn=etc. In the tuple
 # the first value is the *nix service name, the second the start order.
 SERVICE_LIST = {
@@ -55,13 +60,14 @@ def print_msg(message, output_fd=sys.stdout):
 
 
 class Service(object):
-    def __init__(self, service_name, sstore=None, dm_password=None, ldapi=False):
+    def __init__(self, service_name, sstore=None, dm_password=None, ldapi=True, autobind=AUTO):
         self.service_name = service_name
         self.service = ipaservices.service(service_name)
         self.steps = []
         self.output_fd = sys.stdout
         self.dm_password = dm_password
         self.ldapi = ldapi
+        self.autobind = autobind
 
         self.fqdn = socket.gethostname()
         self.admin_conn = None
@@ -77,12 +83,44 @@ class Service(object):
         self.dercert = None
 
     def ldap_connect(self):
-        if self.ldapi:
+        # If DM password is provided, we use it
-            if not self.realm:
+        # If autobind was requested, attempt autobind when root and ldapi
-                raise RuntimeError('realm must be set to use ldapi connection')
+        # If autobind was disabled or not succeeded, go with GSSAPI
-            self.admin_conn = self.__get_conn(None, None, ldapi=True, realm=self.realm)
+        # LDAPI can be used with either autobind or GSSAPI
-        else:
+        # LDAPI requires realm to be set
-            self.admin_conn = self.__get_conn(self.fqdn, self.dm_password)
+        try:
+            if self.ldapi:
+                if not self.realm:
+                    raise errors.NotFound(reason="realm is missing for %s" % (self))
+                conn = ipaldap.IPAdmin(ldapi=self.ldapi, realm=self.realm)
+            else:
+                conn = ipaldap.IPAdmin(self.fqdn, port=389)
+            if self.dm_password:
+                conn.do_simple_bind(bindpw=self.dm_password)
+            elif self.autobind in [AUTO, ENABLED]:
+                if os.getegid() == 0 and self.ldapi:
+                    try:
+                        # autobind
+                        pw_name = pwd.getpwuid(os.geteuid()).pw_name
+                        conn.do_external_bind(pw_name)
+                    except errors.NotFound, e:
+                        if self.autobind == AUTO:
+                            # Fall back
+                            conn.do_sasl_gssapi_bind()
+                        else:
+                            # autobind was required and failed, raise
+                            # exception that it failed
+                            raise e
+                else:
+                    conn.do_sasl_gssapi_bind()
+            else:
+                conn.do_sasl_gssapi_bind()
+        except Exception, e:
+            root_logger.debug("Could not connect to the Directory Server on %s: %s" % (self.fqdn, str(e)))
+            raise e
+
+        self.admin_conn = conn
+
 
     def ldap_disconnect(self):
         self.admin_conn.unbind()
@@ -93,7 +131,6 @@ class Service(object):
         pw_name = None
         fd = None
         path = ipautil.SHARE_DIR + ldif
-        hostname = installutils.get_fqdn()
         nologlist=[]
 
         if sub_dict is not None:
@@ -107,15 +144,25 @@ class Service(object):
             if sub_dict.has_key('RANDOM_PASSWORD'):
                 nologlist.append(sub_dict['RANDOM_PASSWORD'])
 
+        args = ["/usr/bin/ldapmodify", "-v", "-f", path]
+
+        # As we always connect to the local host,
+        # use URI of admin connection
+        if not self.admin_conn:
+            self.ldap_connect()
+        args += ["-H", self.admin_conn._uri]
+
+        auth_parms = []
         if self.dm_password:
             [pw_fd, pw_name] = tempfile.mkstemp()
             os.write(pw_fd, self.dm_password)
             os.close(pw_fd)
             auth_parms = ["-x", "-D", "cn=Directory Manager", "-y", pw_name]
         else:
-            auth_parms = ["-Y", "GSSAPI"]
+            # always try GSSAPI auth when not using DM password or not being root
+            if os.getegid() != 0:
+                auth_parms = ["-Y", "GSSAPI"]
 
-        args = ["/usr/bin/ldapmodify", "-h", hostname, "-v", "-f", path]
         args += auth_parms
 
         try:
@@ -181,8 +228,19 @@ class Service(object):
         This server cert should be in DER format.
         """
 
-        if not self.admin_conn:
+        # add_cert_to_service() is relatively rare operation
-            self.ldap_connect()
+        # we actually call it twice during ipa-server-install, for different
+        # instances: ds and cs. Unfortunately, it may happen that admin
+        # connection was created well before add_cert_to_service() is called
+        # If there are other operations in between, it will become stale and
+        # since we are using SimpleLDAPObject, not ReconnectLDAPObject, the
+        # action will fail. Thus, explicitly disconnect and connect again.
+        # Using ReconnectLDAPObject instead of SimpleLDAPObject was considered
+        # but consequences for other parts of the framework are largely
+        # unknown.
+        if self.admin_conn:
+            self.ldap_disconnect()
+        self.ldap_connect()
 
         dn = "krbprincipalname=%s,cn=services,cn=accounts,%s" % (self.principal, self.suffix)
         mod = [(ldap.MOD_ADD, 'userCertificate', self.dercert)]
@@ -268,33 +326,6 @@ class Service(object):
 
         self.steps = []
 
-    def __get_conn(self, fqdn, dm_password, ldapi=False, realm=None):
-        # If we are passed a password we'll use it as the DM password
-        # otherwise we'll do a GSSAPI bind.
-        try:
-#            conn = ipaldap.IPAdmin(fqdn, port=636, cacert=CACERT)
-            if ldapi:
-                conn = ipaldap.IPAdmin(ldapi=ldapi, realm=realm)
-            else:
-                conn = ipaldap.IPAdmin(fqdn, port=389)
-            if dm_password:
-                conn.do_simple_bind(bindpw=dm_password)
-            elif os.getegid() == 0 and self.ldapi:
-                try:
-                    # autobind
-                    pw_name = pwd.getpwuid(os.geteuid()).pw_name
-                    conn.do_external_bind(pw_name)
-                except errors.NotFound:
-                    # Fall back
-                    conn.do_sasl_gssapi_bind()
-            else:
-                conn.do_sasl_gssapi_bind()
-        except Exception, e:
-            root_logger.debug("Could not connect to the Directory Server on %s: %s" % (fqdn, str(e)))
-            raise e
-
-        return conn
-
     def ldap_enable(self, name, fqdn, dm_password, ldap_suffix):
         self.disable()
         if not self.admin_conn:
@@ -318,11 +349,14 @@ class Service(object):
             raise e
 
 class SimpleServiceInstance(Service):
-    def create_instance(self, gensvc_name=None, fqdn=None, dm_password=None, ldap_suffix=None):
+    def create_instance(self, gensvc_name=None, fqdn=None, dm_password=None, ldap_suffix=None, realm=None):
         self.gensvc_name = gensvc_name
         self.fqdn = fqdn
         self.dm_password = dm_password
         self.suffix = ldap_suffix
+        self.realm = realm
+        if not realm:
+            self.ldapi = False
 
         self.step("starting %s " % self.service_name, self.__start)
         self.step("configuring %s to start on boot" % self.service_name, self.__enable)