ipaclient: Defer creating the final krb5.conf on clients

A temporary krb5 configuration was used to join the domain in
ipaclient_join. After that the final krkb5 configuration was created
with enabled DNS discovery and used for the remainaing tasks, where also
a connection to the IPA API was done.

With several servers the DNS discovery could have picked up a different
server. If the client deployment was faster than the replication this
could have lead to an unknown host error.

The issue was seen in performance testing where many simultaneous client
enrollments have been done..

The goal is to keep server affinity as long as possible within the
deployment process:

The temporary krb5.conf that was used before in ipaclient_join was
pulled out into an own module. The generated temporary krb5.conf is now
used in ipaclient_join and also ipaclient_api.

The generation of the final krb5.conf is moved to the end of the
deployment process.

Same as: https://pagure.io/freeipa/issue/9228

The setup of certmonger has been pulled out of ipaclient_setup_nss and moved
to the end of the process after generating the final krb5.conf as it will
use t will only use /etc/krb5.conf.

Certificate issuance may fail during deployment due to using the final
krb5.conf, but certmonger will re-try the request in this case.

Same as: https://pagure.io/freeipa/issue/9246

roles/ipaclient/library/ipaclient_api.py

@@ -55,6 +55,10 @@ options:
     type: bool
     required: no
     default: no
+  krb_name:
+    description: The krb5 config file name
+    type: str
+    required: yes
 author:
     - Thomas Woerner (@t-woerner)
 '''
@@ -65,6 +69,7 @@ EXAMPLES = '''
     servers: ["server1.example.com","server2.example.com"]
     domain: example.com
     hostname: client1.example.com
+    krb_name: /tmp/tmpkrb5.conf
   register: result_ipaclient_api
 '''
 
@@ -99,6 +104,7 @@ def main():
             realm=dict(required=True, type='str'),
             hostname=dict(required=True, type='str'),
             debug=dict(required=False, type='bool', default="false"),
+            krb_name=dict(required=True, type='str'),
         ),
         supports_check_mode=False,
     )
@@ -110,9 +116,11 @@ def main():
     realm = module.params.get('realm')
     hostname = module.params.get('hostname')
     debug = module.params.get('debug')
+    krb_name = module.params.get('krb_name')
 
     host_principal = 'host/%s@%s' % (hostname, realm)
     os.environ['KRB5CCNAME'] = paths.IPA_DNS_CCACHE
+    os.environ['KRB5_CONFIG'] = krb_name
 
     ca_certs = x509.load_certificate_list_from_file(paths.IPA_CA_CRT)
     if 40500 <= NUM_VERSION < 40590:

roles/ipaclient/library/ipaclient_join.py

@@ -46,10 +46,6 @@ options:
     type: list
     elements: str
     required: yes
-  domain:
-    description: Primary DNS domain of the IPA deployment
-    type: str
-    required: yes
   realm:
     description: Kerberos realm name of the IPA deployment
     type: str
@@ -58,10 +54,6 @@ options:
     description: Fully qualified name of this host
     type: str
     required: yes
-  kdc:
-    description: The name or address of the host running the KDC
-    type: str
-    required: yes
   basedn:
     description: The basedn of the IPA server (of the form dc=example,dc=com)
     type: str
@@ -102,6 +94,10 @@ options:
     description: Turn on extra debugging
     type: bool
     required: no
+  krb_name:
+    description: The krb5 config file name
+    type: str
+    required: yes
 author:
     - Thomas Woerner (@t-woerner)
 '''
@@ -111,27 +107,25 @@ EXAMPLES = '''
 - name: Join IPA in force mode with maximum 5 kinit attempts
   ipaclient_join:
     servers: ["server1.example.com","server2.example.com"]
-    domain: example.com
     realm: EXAMPLE.COM
-    kdc: server1.example.com
     basedn: dc=example,dc=com
     hostname: client1.example.com
     principal: admin
     password: MySecretPassword
     force_join: yes
     kinit_attempts: 5
+    krb_name: /tmp/tmpkrb5.conf
 
 # Join IPA to get the keytab using ipadiscovery return values
 - name: Join IPA
   ipaclient_join:
     servers: "{{ ipadiscovery.servers }}"
-    domain: "{{ ipadiscovery.domain }}"
     realm: "{{ ipadiscovery.realm }}"
-    kdc: "{{ ipadiscovery.kdc }}"
     basedn: "{{ ipadiscovery.basedn }}"
     hostname: "{{ ipadiscovery.hostname }}"
     principal: admin
     password: MySecretPassword
+    krb_name: /tmp/tmpkrb5.conf
 '''
 
 RETURN = '''
@@ -147,9 +141,9 @@ import tempfile
 from ansible.module_utils.basic import AnsibleModule
 from ansible.module_utils.ansible_ipa_client import (
     setup_logging, check_imports,
-    SECURE_PATH, sysrestore, paths, options, configure_krb5_conf,
+    SECURE_PATH, sysrestore, paths, options, realm_to_suffix, kinit_keytab,
-    realm_to_suffix, kinit_keytab, GSSError, kinit_password, NUM_VERSION,
+    GSSError, kinit_password, NUM_VERSION, get_ca_cert, get_ca_certs, errors,
-    get_ca_cert, get_ca_certs, errors, run
+    run
 )
 
 
@@ -157,10 +151,8 @@ def main():
     module = AnsibleModule(
         argument_spec=dict(
             servers=dict(required=True, type='list', elements='str'),
-            domain=dict(required=True, type='str'),
             realm=dict(required=True, type='str'),
             hostname=dict(required=True, type='str'),
-            kdc=dict(required=True, type='str'),
             basedn=dict(required=True, type='str'),
             principal=dict(required=False, type='str'),
             password=dict(required=False, type='str', no_log=True),
@@ -170,6 +162,7 @@ def main():
             force_join=dict(required=False, type='bool'),
             kinit_attempts=dict(required=False, type='int', default=5),
             debug=dict(required=False, type='bool'),
+            krb_name=dict(required=True, type='str'),
         ),
         supports_check_mode=False,
     )
@@ -179,11 +172,9 @@ def main():
     setup_logging()
 
     servers = module.params.get('servers')
-    domain = module.params.get('domain')
     realm = module.params.get('realm')
     hostname = module.params.get('hostname')
     basedn = module.params.get('basedn')
-    kdc = module.params.get('kdc')
     force_join = module.params.get('force_join')
     principal = module.params.get('principal')
     password = module.params.get('password')
@@ -192,6 +183,7 @@ def main():
     ca_cert_file = module.params.get('ca_cert_file')
     kinit_attempts = module.params.get('kinit_attempts')
     debug = module.params.get('debug')
+    krb_name = module.params.get('krb_name')
 
     if password is not None and keytab is not None:
         module.fail_json(msg="Password and keytab cannot be used together")
@@ -199,12 +191,10 @@ def main():
     if password is None and admin_keytab is None:
         module.fail_json(msg="Password or admin_keytab is needed")
 
-    client_domain = hostname[hostname.find(".") + 1:]
     nolog = tuple()
     env = {'PATH': SECURE_PATH}
     fstore = sysrestore.FileStore(paths.IPA_CLIENT_SYSRESTORE)
     host_principal = 'host/%s@%s' % (hostname, realm)
-    sssd = True
 
     options.ca_cert_file = ca_cert_file
     options.principal = principal
@@ -215,19 +205,6 @@ def main():
     changed = False
     already_joined = False
     try:
-        (krb_fd, krb_name) = tempfile.mkstemp()
-        os.close(krb_fd)
-        configure_krb5_conf(
-            cli_realm=realm,
-            cli_domain=domain,
-            cli_server=servers,
-            cli_kdc=kdc,
-            dnsok=False,
-            filename=krb_name,
-            client_domain=client_domain,
-            client_hostname=hostname,
-            configure_sssd=sssd,
-            force=False)
         env['KRB5_CONFIG'] = krb_name
         ccache_dir = tempfile.mkdtemp(prefix='krbcc')
         ccache_name = os.path.join(ccache_dir, 'ccache')
@@ -336,27 +313,17 @@ def main():
                          paths.IPA_DNS_CCACHE,
                          config=krb_name,
                          attempts=kinit_attempts)
-            env['KRB5CCNAME'] = os.environ['KRB5CCNAME'] = paths.IPA_DNS_CCACHE
         except GSSError as e:
             # failure to get ticket makes it impossible to login and
             # bind from sssd to LDAP, abort installation
             module.fail_json(msg="Failed to obtain host TGT: %s" % e)
 
     finally:
-        try:
-            os.remove(krb_name)
-        except OSError:
-            module.fail_json(msg="Could not remove %s" % krb_name)
         if ccache_dir is not None:
             try:
                 os.rmdir(ccache_dir)
             except OSError:
                 pass
-        if os.path.exists(krb_name + ".ipabkp"):
-            try:
-                os.remove(krb_name + ".ipabkp")
-            except OSError:
-                module.fail_json(msg="Could not remove %s.ipabkp" % krb_name)
 
     module.exit_json(changed=changed,
                      already_joined=already_joined)

roles/ipaclient/library/ipaclient_setup_certmonger.py

@@ -0,0 +1,123 @@
+# -*- coding: utf-8 -*-
+
+# Authors:
+#   Thomas Woerner <twoerner@redhat.com>
+#
+# Based on ipa-client-install code
+#
+# Copyright (C) 2017-2022  Red Hat
+# see file 'COPYING' for use and warranty information
+#
+# 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/>.
+
+from __future__ import (absolute_import, division, print_function)
+
+__metaclass__ = type
+
+ANSIBLE_METADATA = {
+    'metadata_version': '1.0',
+    'supported_by': 'community',
+    'status': ['preview'],
+}
+
+DOCUMENTATION = '''
+---
+module: ipaclient_setup_certmonger
+short_description: Setup certmonger for IPA client
+description: Setup certmonger for IPA client
+options:
+  realm:
+    description: Kerberos realm name of the IPA deployment
+    type: str
+    required: yes
+  hostname:
+    description: Fully qualified name of this host
+    type: str
+    required: yes
+  subject_base:
+    description: |
+      The certificate subject base (default O=<realm-name>).
+      RDNs are in LDAP order (most specific RDN first).
+    type: str
+    required: yes
+  ca_enabled:
+    description: Whether the Certificate Authority is enabled or not
+    type: bool
+    required: yes
+  request_cert:
+    description: Request certificate for the machine
+    type: bool
+    required: yes
+author:
+    - Thomas Woerner (@t-woerner)
+'''
+
+EXAMPLES = '''
+- name: Setup certmonger for IPA client
+  ipaclient_setup_certmonger:
+    realm: EXAMPLE.COM
+    hostname: client1.example.com
+    subject_base: O=EXAMPLE.COM
+    ca_enabled: true
+    request_cert: false
+'''
+
+RETURN = '''
+'''
+
+from ansible.module_utils.basic import AnsibleModule
+from ansible.module_utils.ansible_ipa_client import (
+    setup_logging, check_imports,
+    options, sysrestore, paths, ScriptError, configure_certmonger
+)
+
+
+def main():
+    module = AnsibleModule(
+        argument_spec=dict(
+            realm=dict(required=True, type='str'),
+            hostname=dict(required=True, type='str'),
+            subject_base=dict(required=True, type='str'),
+            ca_enabled=dict(required=True, type='bool'),
+            request_cert=dict(required=True, type='bool'),
+        ),
+        supports_check_mode=False,
+    )
+
+    module._ansible_debug = True
+    check_imports(module)
+    setup_logging()
+
+    cli_realm = module.params.get('realm')
+    hostname = module.params.get('hostname')
+    subject_base = module.params.get('subject_base')
+    ca_enabled = module.params.get('ca_enabled')
+
+    fstore = sysrestore.FileStore(paths.IPA_CLIENT_SYSRESTORE)
+
+    options.request_cert = module.params.get('request_cert')
+    options.hostname = hostname
+
+    try:
+        configure_certmonger(fstore, subject_base, cli_realm, hostname,
+                             options, ca_enabled)
+
+    except ScriptError as e:
+        module.fail_json(msg=str(e))
+
+    module.exit_json(changed=True)
+
+
+if __name__ == '__main__':
+    main()

roles/ipaclient/library/ipaclient_setup_nss.py

@@ -177,7 +177,7 @@ from ansible.module_utils.ansible_ipa_client import (
     options, sysrestore, paths, ansible_module_get_parsed_ip_addresses,
     api, errors, create_ipa_nssdb, ipautil, ScriptError, CLIENT_INSTALL_ERROR,
     get_certs_from_ldap, DN, certstore, x509, logger, certdb,
-    CalledProcessError, tasks, client_dns, configure_certmonger, services,
+    CalledProcessError, tasks, client_dns, services,
     update_ssh_keys, save_state, configure_ldap_conf, configure_nslcd_conf,
     configure_openldap_conf, hardcode_ldap_server, getargspec, NUM_VERSION,
     serialization
@@ -350,8 +350,6 @@ def main():
 
         if not options.on_master:
             client_dns(cli_server[0], hostname, options)
-            configure_certmonger(fstore, subject_base, cli_realm, hostname,
-                                 options, ca_enabled)
 
         if hasattr(paths, "SSH_CONFIG_DIR"):
             ssh_config_dir = paths.SSH_CONFIG_DIR

roles/ipaclient/library/ipaclient_temp_krb5.py

@@ -0,0 +1,163 @@
+# -*- coding: utf-8 -*-
+
+# Authors:
+#   Thomas Woerner <twoerner@redhat.com>
+#
+# Based on ipa-client-install code
+#
+# Copyright (C) 2017-2022  Red Hat
+# see file 'COPYING' for use and warranty information
+#
+# 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/>.
+
+from __future__ import (absolute_import, division, print_function)
+
+__metaclass__ = type
+
+ANSIBLE_METADATA = {
+    'metadata_version': '1.0',
+    'supported_by': 'community',
+    'status': ['preview'],
+}
+
+DOCUMENTATION = '''
+---
+module: ipaclient_temp_krb5
+short_description:
+  Create temporary krb5 configuration.
+description:
+  Create temporary krb5 configuration for deferring the creation of the final
+  krb5.conf on clients
+options:
+  servers:
+    description: Fully qualified name of IPA servers to enroll to
+    type: list
+    elements: str
+    required: yes
+  domain:
+    description: Primary DNS domain of the IPA deployment
+    type: str
+    required: yes
+  realm:
+    description: Kerberos realm name of the IPA deployment
+    type: str
+    required: yes
+  hostname:
+    description: Fully qualified name of this host
+    type: str
+    required: yes
+  kdc:
+    description: The name or address of the host running the KDC
+    type: str
+    required: yes
+  on_master:
+    description: Whether the configuration is done on the master or not
+    type: bool
+    required: no
+    default: no
+author:
+    - Thomas Woerner (@t-woerner)
+'''
+
+EXAMPLES = '''
+# Test IPA with local keytab
+- name: Test IPA in force mode with maximum 5 kinit attempts
+  ipaclient_test_keytab:
+    servers: ["server1.example.com","server2.example.com"]
+    domain: example.com
+    realm: EXAMPLE.COM
+    kdc: server1.example.com
+    hostname: client1.example.com
+
+# Test IPA with ipadiscovery return values
+- name: Join IPA
+  ipaclient_test_keytab:
+    servers: "{{ ipadiscovery.servers }}"
+    domain: "{{ ipadiscovery.domain }}"
+    realm: "{{ ipadiscovery.realm }}"
+    kdc: "{{ ipadiscovery.kdc }}"
+    hostname: "{{ ipadiscovery.hostname }}"
+'''
+
+RETURN = '''
+krb_name:
+  description: The krb5 config file name
+  returned: always
+  type: str
+'''
+
+import os
+import tempfile
+
+from ansible.module_utils.basic import AnsibleModule
+from ansible.module_utils.ansible_ipa_client import (
+    setup_logging, check_imports, configure_krb5_conf
+)
+
+
+def main():
+    module = AnsibleModule(
+        argument_spec=dict(
+            servers=dict(required=True, type='list', elements='str'),
+            domain=dict(required=True, type='str'),
+            realm=dict(required=True, type='str'),
+            hostname=dict(required=True, type='str'),
+            kdc=dict(required=True, type='str'),
+            on_master=dict(required=False, type='bool', default=False),
+        ),
+        supports_check_mode=False,
+    )
+
+    module._ansible_debug = True
+    check_imports(module)
+    setup_logging()
+
+    servers = module.params.get('servers')
+    domain = module.params.get('domain')
+    realm = module.params.get('realm')
+    hostname = module.params.get('hostname')
+    kdc = module.params.get('kdc')
+    client_domain = hostname[hostname.find(".") + 1:]
+
+    krb_name = None
+    # Create temporary krb5 configuration
+    try:
+        (krb_fd, krb_name) = tempfile.mkstemp()
+        os.close(krb_fd)
+        configure_krb5_conf(
+            cli_realm=realm,
+            cli_domain=domain,
+            cli_server=servers,
+            cli_kdc=kdc,
+            dnsok=False,
+            filename=krb_name,
+            client_domain=client_domain,
+            client_hostname=hostname,
+            configure_sssd=True,
+            force=False)
+    except Exception as ex:
+        if krb_name:
+            try:
+                os.remove(krb_name)
+            except OSError:
+                module.fail_json(msg="Could not remove %s" % krb_name)
+        module.fail_json(
+            msg="Failed to create temporary krb5 configuration: %s" % str(ex))
+
+    module.exit_json(changed=False,
+                     krb_name=krb_name)
+
+
+if __name__ == '__main__':
+    main()

roles/ipaclient/library/ipaclient_test_keytab.py

@@ -244,6 +244,12 @@ def main():
                 os.remove(krb_name)
             except OSError:
                 module.fail_json(msg="Could not remove %s" % krb_name)
+            if os.path.exists(krb_name + ".ipabkp"):
+                try:
+                    os.remove(krb_name + ".ipabkp")
+                except OSError:
+                    module.fail_json(
+                        msg="Could not remove %s.ipabkp" % krb_name)
 
     module.exit_json(changed=False,
                      krb5_keytab_ok=krb5_keytab_ok,

roles/ipaclient/tasks/install.yml

@@ -239,12 +239,19 @@
       hostname: "{{ result_ipaclient_test.hostname }}"
     when: not ipaclient_on_master | bool
 
-  - name: Install - Join IPA
+  - name: Install - Create temporary krb5 configuration
-    ipaclient_join:
+    ipaclient_temp_krb5:
       servers: "{{ result_ipaclient_test.servers }}"
       domain: "{{ result_ipaclient_test.domain }}"
       realm: "{{ result_ipaclient_test.realm }}"
+      hostname: "{{ result_ipaclient_test.hostname }}"
       kdc: "{{ result_ipaclient_test.kdc }}"
+    register: result_ipaclient_temp_krb5
+
+  - name: Install - Join IPA
+    ipaclient_join:
+      servers: "{{ result_ipaclient_test.servers }}"
+      realm: "{{ result_ipaclient_test.realm }}"
       basedn: "{{ result_ipaclient_test.basedn }}"
       hostname: "{{ result_ipaclient_test.hostname }}"
       force_join: "{{ ipaclient_force_join | default(omit) }}"
@@ -255,6 +262,7 @@
       admin_keytab: "{{ ipaadmin_keytab if ipaadmin_keytab is defined and not ipaclient_use_otp | bool else omit }}"
       # ca_cert_file: "{{ ipaclient_ca_cert_file | default(omit) }}"
       kinit_attempts: "{{ ipaclient_kinit_attempts | default(omit) }}"
+      krb_name: "{{ result_ipaclient_temp_krb5.krb_name }}"
     register: result_ipaclient_join
     when: not ipaclient_on_master | bool and
           (not result_ipaclient_test_keytab.krb5_keytab_ok or
@@ -323,26 +331,13 @@
           "{{ ipassd_no_krb5_offline_passwords
               | default(ipasssd_no_krb5_offline_passwords) }}"
 
-    - name: Install - Configure krb5 for IPA realm
-      ipaclient_setup_krb5:
-        realm: "{{ result_ipaclient_test.realm }}"
-        domain: "{{ result_ipaclient_test.domain }}"
-        servers: "{{ result_ipaclient_test.servers }}"
-        kdc: "{{ result_ipaclient_test.kdc }}"
-        dnsok: "{{ result_ipaclient_test.dnsok }}"
-        client_domain: "{{ result_ipaclient_test.client_domain }}"
-        hostname: "{{ result_ipaclient_test.hostname }}"
-        sssd: "{{ result_ipaclient_test.sssd }}"
-        force: "{{ ipaclient_force }}"
-        # on_master: "{{ ipaclient_on_master }}"
-      when: not ipaclient_on_master | bool
-
     - name: Install - IPA API calls for remaining enrollment parts
       ipaclient_api:
         servers: "{{ result_ipaclient_test.servers }}"
         realm: "{{ result_ipaclient_test.realm }}"
         hostname: "{{ result_ipaclient_test.hostname }}"
         # debug: yes
+        krb_name: "{{ result_ipaclient_temp_krb5.krb_name }}"
       register: result_ipaclient_api
 
     - name: Install - Fix IPA ca
@@ -412,6 +407,36 @@
         domain: "{{ result_ipaclient_test.domain }}"
         nisdomain: "{{ ipaclient_nisdomain | default(omit) }}"
       when: not ipaclient_no_nisdomain | bool
+
+    - name: Remove temporary krb5.conf
+      ansible.builtin.file:
+        path: "{{ result_ipaclient_temp_krb5.krb_name }}"
+        state: absent
+      when: result_ipaclient_temp_krb5.krb_name is defined
+
+    - name: Install - Configure krb5 for IPA realm
+      ipaclient_setup_krb5:
+        realm: "{{ result_ipaclient_test.realm }}"
+        domain: "{{ result_ipaclient_test.domain }}"
+        servers: "{{ result_ipaclient_test.servers }}"
+        kdc: "{{ result_ipaclient_test.kdc }}"
+        dnsok: "{{ result_ipaclient_test.dnsok }}"
+        client_domain: "{{ result_ipaclient_test.client_domain }}"
+        hostname: "{{ result_ipaclient_test.hostname }}"
+        sssd: "{{ result_ipaclient_test.sssd }}"
+        force: "{{ ipaclient_force }}"
+        # on_master: "{{ ipaclient_on_master }}"
+      when: not ipaclient_on_master | bool
+
+    - name: Install - Configure certmonger
+      ipaclient_setup_certmonger:
+        realm: "{{ result_ipaclient_test.realm }}"
+        hostname: "{{ result_ipaclient_test.hostname }}"
+        subject_base: "{{ result_ipaclient_api.subject_base }}"
+        ca_enabled: "{{ result_ipaclient_api.ca_enabled }}"
+        request_cert: "{{ ipaclient_request_cert }}"
+      when: not ipaclient_on_master | bool
+
   always:
   - name: Install - Restore original admin password if overwritten by OTP
     no_log: yes
@@ -423,3 +448,15 @@
     ansible.builtin.file:
       path: "/etc/ipa/.dns_ccache"
       state: absent
+
+  - name: Remove temporary krb5.conf
+    ansible.builtin.file:
+      path: "{{ result_ipaclient_temp_krb5.krb_name }}"
+      state: absent
+    when: result_ipaclient_temp_krb5.krb_name is defined
+
+  - name: Remove temporary krb5.conf backup
+    ansible.builtin.file:
+      path: "{{ result_ipaclient_temp_krb5.krb_name }}.ipabkp"
+      state: absent
+    when: result_ipaclient_temp_krb5.krb_name is defined