Re: [PATCH 1/2] python/semanage module: Fix handling of -a/-e/-d/-r options

[Nicolas Iooss <nicolas.iooss@m4x.org>]

On Wed, Feb 6, 2019 at 8:43 PM Petr Lautrbach <plautrba@redhat.com> wrote:
>
> Previous code traceback-ed when one of the mentioned option was used without
> any argument as this state was not handled by the argument parser.
>
> action='store' stores arguments as a list while the original
> action='store_const' used str therefore the particular interfaces in
> moduleRecords are changed to be compatible with both.
>
> Fixes:
> ^_^ semanage module -a
> Traceback (most recent call last):
>   File "/usr/sbin/semanage", line 963, in <module>
>     do_parser()
>   File "/usr/sbin/semanage", line 942, in do_parser
>     args.func(args)
>   File "/usr/sbin/semanage", line 608, in handleModule
>     OBJECT.add(args.module_name, args.priority)
>   File "/usr/lib/python3.7/site-packages/seobject.py", line 402, in add
>     if not os.path.exists(file):
>   File "/usr/lib64/python3.7/genericpath.py", line 19, in exists
>     os.stat(path)
> TypeError: stat: path should be string, bytes, os.PathLike or integer, not NoneType
>
> Signed-off-by: Petr Lautrbach <plautrba@redhat.com>

Nice bug :) Nevertheless "if type(module) == str" troubles me because
I except a function to only accept one kind of arguments (either a
list of strings or a string, but not both). Moreover this is
Python3-only code and semanage's shebang does not specify a Python
version (the Python2-equivalent code would have been "if
isinstance(module, basestring)").

I would prefer if the new code looked like this (that I have not tested):

    def set_enabled(self, modules, enable):
        for item_modules in modules:
            for m in item_modules.split():
                # ...

Moreover the "file = file[0]" in moduleRecords.add() looks strange
without a context, which is in handleModule(). I would prefer if this
operation occurred in semanage, where it is clear that args.action_add
always has a single item (because « action='store', nargs=1 »):

    if args.action_add:
        OBJECT.add(args.action_add[0], args.priority)

Nicolas

PS: As setools is now Python3-only and seobject.py requires it, it
seems to be a good time to update the shebang to "#!/usr/bin/python3
-Es".

> ---
>  python/semanage/semanage    | 25 ++++++++++++-------------
>  python/semanage/seobject.py | 10 ++++++++--
>  2 files changed, 20 insertions(+), 15 deletions(-)
>
> diff --git a/python/semanage/semanage b/python/semanage/semanage
> index 6afeac14..9b737fa8 100644
> --- a/python/semanage/semanage
> +++ b/python/semanage/semanage
> @@ -609,14 +609,14 @@ def setupInterfaceParser(subparsers):
>
>  def handleModule(args):
>      OBJECT = seobject.moduleRecords(args)
> -    if args.action == "add":
> -        OBJECT.add(args.module_name, args.priority)
> -    if args.action == "enable":
> -        OBJECT.set_enabled(args.module_name, True)
> -    if args.action == "disable":
> -        OBJECT.set_enabled(args.module_name, False)
> -    if args.action == "remove":
> -        OBJECT.delete(args.module_name, args.priority)
> +    if args.action_add:
> +        OBJECT.add(args.action_add, args.priority)
> +    if args.action_enable:
> +        OBJECT.set_enabled(args.action_enable, True)
> +    if args.action_disable:
> +        OBJECT.set_enabled(args.action_disable, False)
> +    if args.action_remove:
> +        OBJECT.delete(args.action_remove, args.priority)
>      if args.action == "deleteall":
>          OBJECT.deleteall()
>      if args.action == "list":
> @@ -635,14 +635,13 @@ def setupModuleParser(subparsers):
>      parser_add_priority(moduleParser, "module")
>
>      mgroup = moduleParser.add_mutually_exclusive_group(required=True)
> -    parser_add_add(mgroup, "module")
>      parser_add_list(mgroup, "module")
>      parser_add_extract(mgroup, "module")
>      parser_add_deleteall(mgroup, "module")
> -    mgroup.add_argument('-r', '--remove', dest='action', action='store_const', const='remove', help=_("Remove a module"))
> -    mgroup.add_argument('-d', '--disable', dest='action', action='store_const', const='disable', help=_("Disable a module"))
> -    mgroup.add_argument('-e', '--enable', dest='action', action='store_const', const='enable', help=_("Enable a module"))
> -    moduleParser.add_argument('module_name', nargs='?', default=None, help=_('Name of the module to act on'))
> +    mgroup.add_argument('-a', '--add', dest='action_add', action='store', nargs=1, metavar='module_name', help=_("Add a module"))
> +    mgroup.add_argument('-r', '--remove', dest='action_remove', action='store', nargs='+', metavar='module_name', help=_("Remove a module"))
> +    mgroup.add_argument('-d', '--disable', dest='action_disable', action='store', nargs='+', metavar='module_name', help=_("Disable a module"))
> +    mgroup.add_argument('-e', '--enable', dest='action_enable', action='store', nargs='+', metavar='module_name', help=_("Enable a module"))
>      moduleParser.set_defaults(func=handleModule)
>
>
> diff --git a/python/semanage/seobject.py b/python/semanage/seobject.py
> index 556d3ba5..cd2d3457 100644
> --- a/python/semanage/seobject.py
> +++ b/python/semanage/seobject.py
> @@ -401,6 +401,8 @@ class moduleRecords(semanageRecords):
>              print("%-25s %-9s %-5s %s" % (t[0], t[2], t[3], disabled))
>
>      def add(self, file, priority):
> +        if type(file) == list:
> +            file = file[0]
>          if not os.path.exists(file):
>              raise ValueError(_("Module does not exist: %s ") % file)
>
> @@ -413,7 +415,9 @@ class moduleRecords(semanageRecords):
>              self.commit()
>
>      def set_enabled(self, module, enable):
> -        for m in module.split():
> +        if type(module) == str:
> +            module = module.split()
> +        for m in module:
>              rc, key = semanage_module_key_create(self.sh)
>              if rc < 0:
>                  raise ValueError(_("Could not create module key"))
> @@ -435,7 +439,9 @@ class moduleRecords(semanageRecords):
>          if rc < 0:
>              raise ValueError(_("Invalid priority %d (needs to be between 1 and 999)") % priority)
>
> -        for m in module.split():
> +        if type(module) == str:
> +            module = module.split()
> +        for m in module:
>              rc = semanage_module_remove(self.sh, m)
>              if rc < 0 and rc != -2:
>                  raise ValueError(_("Could not remove module %s (remove failed)") % m)
> --
> 2.20.1
>