[v6,0/2] userspace: Implement new format of filename trans rules

Message

Ondrej Mosnacek July 31, 2020, 11:10 a.m. UTC

These patches are the userspace side of the following kernel commits:
c3a276111ea2 ("selinux: optimize storage of filename transitions") [1]
430059024389 ("selinux: implement new format of filename transitions") [2].

The first patch changes libsepol's internal representation of filename
transition rules in a way similar to the kernel commit.

The second patch then builds upon that and implements reading and
writing of the new binary policy format that uses this representation
also in the data layout.

See individual patches for more details.

NOTE: This series unfortunately breaks the build of setools. Moreover,
when an existing build of setools dynamically links against the new
libsepol, it segfaults. Sadly, there doesn't seem to be a nice way of
handling this, since setools relies on non-public libsepol policydb
API/ABI. There is a draft PR that adapts setools to these changes here:
https://github.com/SELinuxProject/setools/pull/50

See also this discussion about the setools impact:
https://lore.kernel.org/selinux/[e-mail]/

Changes in v6:
 - simplify the interface of policydb_filetrans_insert()
   - i.e. make it possible to pass NULL to name_alloc to simplify most
     callers

Changes in v5:
 - fix comment in filename_trans_read() to not change when being moved
 - fix filename_trans_check_datum()
   - destroy temporary ebitmaps at return
   - actually iterate through datums

Changes in v4:
 - rebased on top of latest master branch

Changes in v3:
 - fixed the change in dispol.c to match the rest of the code
 - renamed the helper functions to use the "_compat" suffix rather than
   "_old" and "_new"

Changes in v2:
 - fixed counting rules when reading the new policy format

[1] https://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux.git/commit/?id=c3a276111ea2572399281988b3129683e2a6b60b
[2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=4300590243895ac39e8c97a2f5acd004dad8a42f

Ondrej Mosnacek (2):
  libsepol,checkpolicy: optimize storage of filename transitions
  libsepol: implement POLICYDB_VERSION_COMP_FTRANS

 checkpolicy/policy_define.c                |  49 +---
 checkpolicy/test/dispol.c                  |  20 +-
 libsepol/cil/src/cil_binary.c              |  26 +-
 libsepol/include/sepol/policydb/policydb.h |  18 +-
 libsepol/src/expand.c                      |  56 +---
 libsepol/src/kernel_to_cil.c               |  24 +-
 libsepol/src/kernel_to_conf.c              |  24 +-
 libsepol/src/policydb.c                    | 314 +++++++++++++++++----
 libsepol/src/write.c                       | 101 +++++--
 9 files changed, 433 insertions(+), 199 deletions(-)