Libguestfs - May 2020 - [PATCH v2 2/2] sysprep: add Kerberos keytab file removal

This patch series adds a new virt-sysprep operation to offline unenroll
a guest from FreeIPA. It does so by removing some configuration files
and certificates.

Changes from v1:
- the other patches were pushed, as unrelated and approved
- created a new kerberos-hostkeytab operation

Pino Toscano (2):
  sysprep: add IPA offline unenrollment (RHBZ#1789592)
  sysprep: add Kerberos keytab file removal

 sysprep/Makefile.am                           |  2 +
 .../sysprep_operation_kerberos_hostkeytab.ml  | 38 +++++++++++
 sysprep/sysprep_operation_unenroll_ipa.ml     | 66 +++++++++++++++++++
 3 files changed, 106 insertions(+)
 create mode 100644 sysprep/sysprep_operation_kerberos_hostkeytab.ml
 create mode 100644 sysprep/sysprep_operation_unenroll_ipa.ml

-- 
2.25.4

This new operation unenrolls the guest from a IPA server offline, by
removing the configuration files and certificates.

Thanks to Christian Heimes and François Cami for the hints.
---
 sysprep/Makefile.am                       |  1 +
 sysprep/sysprep_operation_unenroll_ipa.ml | 66 +++++++++++++++++++++++
 2 files changed, 67 insertions(+)
 create mode 100644 sysprep/sysprep_operation_unenroll_ipa.ml

diff --git a/sysprep/Makefile.am b/sysprep/Makefile.am
index 451a3478f..43137ce65 100644
--- a/sysprep/Makefile.am
+++ b/sysprep/Makefile.am
@@ -66,6 +66,7 @@ operations = \
 	sssd_db_log \
 	tmp_files \
 	udev_persistent_net \
+	unenroll_ipa \
 	user_account \
 	utmp yum_uuid
 
diff --git a/sysprep/sysprep_operation_unenroll_ipa.ml
b/sysprep/sysprep_operation_unenroll_ipa.ml
new file mode 100644
index 000000000..32d4947d8
--- /dev/null
+++ b/sysprep/sysprep_operation_unenroll_ipa.ml
@@ -0,0 +1,66 @@
+(* virt-sysprep
+ * Copyright (C) 2020 Red Hat Inc.
+ *
+ * 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 2 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, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *)
+
+open Sysprep_operation
+open Common_gettext.Gettext
+
+module G = Guestfs
+
+let unenroll_ipa_perform (g : Guestfs.guestfs) root side_effects +  let typ =
g#inspect_get_type root in
+  if typ = "linux" then (
+    (* Simple paths with no side effects. *)
+    let paths = [ "/etc/ipa/ca.crt";
+                  "/etc/ipa/default.conf";
+                  "/var/lib/ipa-client/sysrestore/*";
+                  "/var/lib/ipa-client/pki/*" ] in
+    let paths = List.concat (List.map Array.to_list (List.map g#glob_expand
paths)) in
+    List.iter (
+      fun filename ->
+        try g#rm filename with G.Error _ -> ()
+    ) paths;
+
+    (* Certificates in the system CA store. *)
+    let certs = [ "/etc/pki/ca-trust/source/anchors/ipa-ca.crt";
+                  "/usr/local/share/ca-certificates/ipa-ca.crt";
+                  "/etc/pki/ca-trust/source/ipa.p11-kit" ] in
+    List.iter (
+      fun filename ->
+        try
+          g#rm filename;
+          side_effects#update_system_ca_store ()
+        with
+          G.Error _ -> ()
+    ) certs
+  )
+
+let op = {
+  defaults with
+    name = "unenroll-ipa";
+    enabled_by_default = true;
+    heading = s_"Remove the IPA files";
+    pod_description = Some (s_"\
+Remove all the files related to an IPA (Identity, Policy, Audit) system.
+This effectively unenrolls the guest from an IPA server without interacting
+with it.
+
+This operation does not run C<ipa-client>.");
+    perform_on_filesystems = Some unenroll_ipa_perform;
+}
+
+let () = register_operation op
-- 
2.25.4

This new operation removes the Kerberos /etc/krb5.keytab file from the
guest.

Thanks to Christian Heimes and François Cami for the hints.

Related to RHBZ#1789592.
---
 sysprep/Makefile.am                           |  1 +
 .../sysprep_operation_kerberos_hostkeytab.ml  | 38 +++++++++++++++++++
 2 files changed, 39 insertions(+)
 create mode 100644 sysprep/sysprep_operation_kerberos_hostkeytab.ml

diff --git a/sysprep/Makefile.am b/sysprep/Makefile.am
index 43137ce65..95cc7e358 100644
--- a/sysprep/Makefile.am
+++ b/sysprep/Makefile.am
@@ -44,6 +44,7 @@ operations = \
 	firewall_rules \
 	fs_uuids \
 	kerberos_data \
+	kerberos_hostkeytab \
 	lvm_uuids \
 	logfiles \
 	machine_id \
diff --git a/sysprep/sysprep_operation_kerberos_hostkeytab.ml
b/sysprep/sysprep_operation_kerberos_hostkeytab.ml
new file mode 100644
index 000000000..cb3023353
--- /dev/null
+++ b/sysprep/sysprep_operation_kerberos_hostkeytab.ml
@@ -0,0 +1,38 @@
+(* virt-sysprep
+ * Copyright (C) 2020 Red Hat Inc.
+ *
+ * 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 2 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, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *)
+
+open Sysprep_operation
+open Common_gettext.Gettext
+
+module G = Guestfs
+
+let kerberos_hostkeytab_perform (g : Guestfs.guestfs) root side_effects +  let
typ = g#inspect_get_type root in
+  if typ <> "windows" then (
+    (try g#rm "/etc/krb5.keytab" with G.Error _ -> ())
+  )
+
+let op = {
+  defaults with
+    name = "kerberos-hostkeytab";
+    enabled_by_default = true;
+    heading = s_"Remove the Kerberos host keytab file in the guest";
+    perform_on_filesystems = Some kerberos_hostkeytab_perform;
+}
+
+let () = register_operation op
-- 
2.25.4

I was following the bug and saw the comments there.  This
all seems good to me although I still don't know much about
the topic.  ACK.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
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