Commit graph

9 commits

Author SHA1 Message Date
Mike Salvatore
52d9529d1b parser: replace duplicate warn_once() with common function
The warn_once() function is duplicated in 6 different places. A common,
reusable version has been added to parser_common.c.

Signed-off-by: Mike Salvatore <mike.salvatore@canonical.com>
2020-08-09 17:56:31 -04:00
Ash Wilson
1a0294129e Fix remount with bind
The parser is incorrectly screening off the bind flags on remount. The
following patch by Ash Wilson fixes this issue

BugLink: http://bugs.launchpad.net/bugs/1272028

Signed-off-by: Ash Wilson <smashwilson@gmail.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Tyler Hicks <tyhicks@canonical.com>
2015-09-21 12:20:19 -07:00
Tyler Hicks
43ef5bfc70 parser: Clean up the use of MS_REC in mount.h
This patch restricts MS_REC to only be used while defining the MS_RBIND,
MS_RUNBINDABLE, MS_RPRIVATE, MS_RSLAVE, and MS_RSHARED macros.

The MS_R* macros are simply an OR of the corresponding non-recursive
macro and MS_REC:

 #define MS_RBIND	(MS_BIND | MS_REC)

Previously, a shortcut was taken when needing to specify the
non-recursive and recursive macros:

 (MS_BIND | MS_UNBINDABLE | MS_PRIVATE | MS_SLAVE | MS_SHARED | MS_REC)

By using MS_REC above, it is not immediately clear that
MS_R{BIND,UNBINDABLE,PRIVATE,SLAVE,SHARED} are also included.

By restricting the use of MS_REC, this patch improves readability by
forcing the use of the MS_R{BIND,UNBINDABLE,PRIVATE,SLAVE,SHARED} macros
instead of relying on the MS_REC shortcut.

Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: John Johansen <john.johansen@canonical.com>
2014-12-12 08:21:25 -06:00
Tyler Hicks
7de5ebd18f parser: Fail when a device is present with recursive mount make opts
The parser correctly rejects mount make-* options (make-shared,
make-slave, make-private, make-unbindable) when a device is specified
(the source argument of mount(2)). However, it was not rejecting the
recursive make-* options (make-rshared, make-rslave, make-rprivate,
make-runbindable) when a device was specified.

This patch adds the MS_REC bit, which is used to indicate a recursive
option, to the MS_CMDS macro. Without this change, the recursive options
are treated as normal mount options.

Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: John Johansen <john.johansen@canonical.com>
2014-12-12 08:21:09 -06:00
Steve Beattie
a44b6ce0a2 C tools: rename __unused macro to unused
Bug: https://bugzilla.novell.com/show_bug.cgi?id=895495

We define the __unused macro as a shortcut for __attribute__((unused))
to quiet compiler warnings for functions where an argument is unused,
for whatever reason. However, on 64 bit architectures, older glibc's
bits/stat.h header defines an array variable with the name __unused
that collides with our macro and causes the parser to fail to build,
because the resulting macro expansion generates invalid C code.

This commit fixes the issue by removing the __unused macro where it's
not needed (mod_apparmor) and renaming it to 'unused' elsewhere. It also
in some instances reorders the arguments so that the unused macro
appears last consistently.

Signed-off-by: Steve Beattie <steve@nxnw.org>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
Acked-by: John Johansen <john.johansen@canonical.com>
Acked-by: Tyler Hicks <tyhicks@canonical.com>
2014-10-02 12:58:54 -07:00
John Johansen
a066f80372 Convert mount and dbus to be subclasses of a generic rule class
This will simplify add new features as most of the code can reside in
its own class. There are still things to improve but its a start.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Steve Beattie <steve@nxnw.org>
2014-04-07 03:16:50 -07:00
John Johansen
2e3b5ff134 Fix mnt_flags passed for remount
Remount should not be screening off the set of flags it is.  They are
the set of flags that the kernel is masking out for make_type and
should not be used on remount. Instead just screen off the other cmds
that can have their own rules generated.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-By: Steve Beattie <sbeattie@ubuntu.com>
2012-03-22 07:55:58 -07:00
John Johansen
c50858a877 Update permission mapping for changes made to the upstream kernel patch.
The changes are around how user data is handled.

1. permissions are mapped before data is matched
2. If data is to be mapped a AA_CONT_MATCH flag is set in the permissions
   which allows data matching to continue.
3. If data auditing is to occur the AA_AUDIT_MNT_DATA flag is set

This allows better control over matching and auditing of data which can
be binary and should not be matched or audited

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-By: Steve Beattie <sbeattie@ubuntu.com>
2012-03-15 12:54:34 -07:00
John Johansen
c9e31b7fbd Add mount rules
Add the ability to control mounting and unmounting

The basic form of the rules are.

  [audit] [deny] mount [conds]* [device] [ -> [conds] path],
  [audit] [deny] remount [conds]* [path],
  [audit] [deny] umount [conds]* [path],
  [audit] [deny] pivotroot [oldroot=<value>] <path> -> <profile>

  remount is just a short cut for mount options=remount

  where [conds] can be
    fstype=<expr>
    options=<expr>


  conds follow the extended conditional syntax of allowing either:

  * a single value after the equals, which has the same character range as
    regular IDS (ie most anything but it can't be terminated with a , (comma)
    and if spaces or other characters are needed it can be quoted

    eg.
       options=foo
       options = foo
       options="foo bar"

  * a list of values after the equals, the list of values is enclosed within
    parenthesis () and its has a slightly reduced character set but again
    elements can be quoted.

    the separation between elements is whitespace and commas.

    eg.
      options=(foo bar)
      options=(foo, bar)
      options=(foo , bar)
      options=(foo,bar)


The rules are flexible and follow a similar pattern as network, capability,
etc.

  mount,	# allow all mounts, but not umount or pivotroot

  mount fstype=procfs,  # allow mounting procfs anywhere

  mount options=(bind, ro) /foo -> /bar,  # readonly bind mount

  mount /dev/sda -> /mnt,

  mount /dev/sd** -> /mnt/**,

  mount fstype=overlayfs options=(rw,upperdir=/tmp/upper/,lowerdir=/) overlay -> /mnt/

  umount,

  umount /m*,


Currently variables and regexs are are supported on the device and mount
point. ie.
  mount <devince> -> <mount point>,

Regexes are supported in fstype and options.  The options have a further
caveat that regexs only work if the option is fs specific option.

  eg. options=(upperdir=/tmp/*,lowerdir=/)

regex's will not currently work against the standard options like ro, rw
nosuid


Conditionals (fstype) can only be applied to the device (source) at this
time and will be disregarded in situations where the mount is manipulating
an existing mount (bind, remount).

Options can be specified multiple times
  mount option=rw option=(nosuid,upperdir=/foo),

and will be combined together into a single set of values

The ordering of the standard mount options (rw,ro, ...) does not matter
but the ordering of fs specific options does.

Specifying that the value of a particular option does not matter can be
acheived by providing both the positive and negative forms of and option
  option=(rw,ro) options=(suid,nosuid)

For the fs specific options specifying that a particular value does not
matter is achieve using a regex with alternations.

Improvements to the syntax and order restrictions are planned for the
future.

Signed-off-by: John Johansen <john.johansen@canonical.com>
2012-02-24 04:19:38 -08:00