Commit Graph

3 Commits

Author SHA1 Message Date
Chris PeBenito
dbf2c197c7 Genfscon: Look up object class references since object class values are not static.
The object class values have not been static for many years.  This has only
worked because libsepol was similarly setting static class values.  This
will soon be removed, see SELinuxProject/selinux#200.

Add file object classes to the unit tests where genfscons are used.  The
classes are added in the same alignment as the static values since old
policies will have these class values.

Remove static class values from sepol.pxd.

Closes #39

Signed-off-by: Chris PeBenito <pebenito@ieee.org>
2020-03-10 15:55:24 -04:00
James Carter
89cad5e1b7 Change how differences in AV rules are generated in sediff
The primary motivation for the change is to correctly handle redundant
rules. Recent changes in the SELinux toolchain added support for an
optimization that removes redundant rules from a policy. These are
conditional rules that are either already specified in unconditional
policy or rules using types that are also specified more generally
through an attribute. Since attributes are always expanded in sediff,
the second type of redundant rules are already effectively removed. But
redundant conditional rules show up as differences when a binary version
of a policy that has been optimized is compared to one that has not been.

A secondary motivation for the change is to reduce memory usage and diff
times. A modern Fedora policy cannot be diffed with a system with less than
32Gb of memory and it takes over four hours to complete.

With this change AV rules are processed by creating a data structure which
consists of nested dictionaries that store BOTH the left and the right
policies. All of the keys are interned strings to save space.

The basic structure is
  rule_db[cond_exp][block_bool][src][tgt][tclass]=sides
where:
  cond_exp is a boolean expression
  block_bool is either true or false
  src is the source type
  tgt is the target type
  tclass is the target class
  sides is a namedtuple with "left" and "right" attributes
    Each side is either None or another namedtuple with "perms" and
    "orig_rule" attributes
      perms is the set of permissions for this rule
      orig_rule is the original unexpanded rule

These changes improve diff times and memory usage.
Without the change
                         Time        Memory Usage
Older Fedora Policy    3 min 17 sec      4.5Gb
Recent Refpolicy       4 min 19 sec      6.0Gb
Recent Fedora Policy   4 hrs  9 min     31.9Gb

With the change
                         Time        Memory Usage
Older Fedora Policy          28 sec      1.7Gb
Recent Refpolicy             34 sec      1.9Gb
Recent Fedora Policy   4 min 45 sec      7.7Gb

Also added a unit test to check that redundant rules are removed.

Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
2019-10-24 09:00:19 -04:00
Chris PeBenito
4684eca5bc tests: Revise unit tests for binary-only policy support.
Closes #72
2018-06-15 20:26:49 -04:00