[Libguestfs] [PATCH 1/2] sysprep: remove ca certificates in the guest

[Richard W.M. Jones]

On Wed, May 09, 2012 at 06:08:54PM +0800, Wanlong Gao wrote:
> Remove the ca certificates.
> 
> Signed-off-by: Wanlong Gao <gaowanlong at cn.fujitsu.com>
> ---
>  sysprep/Makefile.am                          |    2 +
>  sysprep/sysprep_operation_ca_certificates.ml |   62 ++++++++++++++++++++++++++
>  2 files changed, 64 insertions(+)
>  create mode 100644 sysprep/sysprep_operation_ca_certificates.ml
> 
> diff --git a/sysprep/Makefile.am b/sysprep/Makefile.am
> index d82e5ae..c6292cc 100644
> --- a/sysprep/Makefile.am
> +++ b/sysprep/Makefile.am
> @@ -35,6 +35,7 @@ SOURCES = \
>  	sysprep_operation.ml \
>  	sysprep_operation.mli \
>  	sysprep_operation_bash_history.ml \
> +	sysprep_operation_ca_certificates.ml \
>  	sysprep_operation_cron_spool.ml \
>  	sysprep_operation_dhcp_client_state.ml \
>  	sysprep_operation_dhcp_server_state.ml \
> @@ -68,6 +69,7 @@ OBJECTS = \
>  	utils.cmx \
>  	sysprep_operation.cmx \
>  	sysprep_operation_bash_history.cmx \
> +	sysprep_operation_ca_certificates.cmx \
>  	sysprep_operation_cron_spool.cmx \
>  	sysprep_operation_dhcp_client_state.cmx \
>  	sysprep_operation_dhcp_server_state.cmx \
> diff --git a/sysprep/sysprep_operation_ca_certificates.ml b/sysprep/sysprep_operation_ca_certificates.ml
> new file mode 100644
> index 0000000..82b4189
> --- /dev/null
> +++ b/sysprep/sysprep_operation_ca_certificates.ml
> @@ -0,0 +1,62 @@
> +(* virt-sysprep
> + * Copyright (C) 2012 FUJITSU LIMITED
> + *
> + * 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 Sysprep_gettext.Gettext
> +
> +module G = Guestfs
> +
> +let ca_certificates_perform g root =
> +  let typ = g#inspect_get_type root in
> +  if typ <> "windows" then (
> +    let paths = [ "/etc/pki/CA/certs/*";
> +                  "/etc/pki/CA/crl/*";
> +                  "/etc/pki/CA/newcerts/*";
> +                  "/etc/pki/CA/private/*";
> +                  "/etc/pki/tls/private/*";
> +                  "/etc/pki/tls/certs/*.crt"; ] in
> +    let excepts = [ "/etc/pki/tls/certs/ca-bundle.crt";
> +                    "/etc/pki/tls/certs/ca-bundle.trust.crt"; ] in

I've no idea if it is correct to remove these files.  These
directories on my machines are all empty.  Also what happens if a user
adds a custom certificate to a machine?  Perhaps this operation should
be included in sysprep but disabled by default?

> +    List.iter (
> +      fun path ->
> +        let files = g#glob_expand path in
> +        Array.iter (
> +          fun file ->
> +            List.iter (
> +              fun except ->
> +                if file <> except then (
> +                  try g#rm file with G.Error _ -> ()
> +                )
> +            ) excepts;
> +          ) files;

The logic here is wrong.  As written, this will delete all the files,
including exceptions.  You probably want to use a set, something like
this (not tested):

  (* put this near to the top of the file, after the 'open's *)
  module StringSet = Set.Make (String)

  ...

  (* expand the paths and add them to a string set *)
  let paths = List.concat (List.map g#glob_expand paths) in
  let set = List.fold_right StringSet.add paths StringSet.empty in

  (* make a set from the exceptions *)
  let excepts = List.fold_right StringSet.add excepts StringSet.empty in

  (* remove exceptions from set *)
  let set = StringSet.diff set excepts in

  (* remove the remaining files *)
  StringSet.iter (
    fun filename ->
      try g#rm filename with G.Error _ -> ()
  ) set

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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