Provide more detailed log messages containing all relevant CIL and
high-level language source file information through cil_tree_log().
cil_tree_log() uses two new functions: cil_tree_get_next_path() and
cil_tree_get_cil_path().
cil_tree_get_next_path() traverses up the parse tree or AST until
it finds the next CIL or high-level language source information nodes.
It will return the path and whether or not the path is for a CIL file.
cil_tree_get_cil_path() uses cil_tree_get_next_path() to return
the CIL path.
Example cil_tree_log() message:
Problem at policy.cil:21 from foo.hll:11 from bar.hll:2
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Use some of the functionality recently added to support high-level
language line marking to track the CIL filename.
The goal is to eventually remove the path field from the tree node
struct and offset the addtion of the hll_line field.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Adds support for tracking original file and line numbers for
better error reporting when a high-level language is translated
into CIL.
This adds a field called "hll_line" to struct cil_tree_node which
increases memory usage by 5%.
Syntax:
;;* lm(s|x) LINENO FILENAME
(CIL STATEMENTS)
;;* lme
lms is used when each of the following CIL statements corresponds
to a line in the original file.
lmx is used when the following CIL statements are all expanded
from a single high-level language line.
lme ends a line mark block.
Example:
;;* lms 1 foo.hll
(CIL-1)
(CIL-2)
;;* lme
;;* lmx 10 bar.hll
(CIL-3)
(CIL-4)
;;* lms 100 baz.hll
(CIL-5)
(CIL-6)
;;* lme
(CIL-7)
;;* lme
CIL-1 is from line 1 of foo.hll
CIL-2 is from line 2 of foo.hll
CIL-3 is from line 10 of bar.hll
CIL-4 is from line 10 of bar.hll
CIL-5 is from line 100 of baz.hll
CIL-6 is from line 101 of baz.hll
CIL-7 is from line 10 of bar.hll
Based on work originally done by Yuli Khodorkovskiy of Tresys.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Change logic of bounds checking to match kernel's bound checking.
The following explanation is taken from Stephen Smalley's kernel
patch.
Under the new logic, if the source type and target types are both
bounded, then the parent of the source type must be allowed the same
permissions to the parent of the target type. If only the source
type is bounded, then the parent of the source type must be allowed
the same permissions to the target type.
Examples of the new logic and comparisons with the old logic:
1. If we have:
typebounds A B;
then:
allow B self:process <permissions>;
will satisfy the bounds constraint iff:
allow A self:process <permissions>;
is also allowed in policy.
Under the old logic, the allow rule on B satisfies the
bounds constraint if any of the following three are allowed:
allow A B:process <permissions>; or
allow B A:process <permissions>; or
allow A self:process <permissions>;
However, either of the first two ultimately require the third to satisfy
the bounds constraint under the old logic, and therefore this degenerates
to the same result (but is more efficient - we only need to perform
one compute_av call).
2. If we have:
typebounds A B;
typebounds A_exec B_exec;
then:
allow B B_exec:file <permissions>;
will satisfy the bounds constraint iff:
allow A A_exec:file <permissions>;
is also allowed in policy.
This is essentially the same as #1; it is merely included as
an example of dealing with object types related to a bounded domain
in a manner that satisfies the bounds relationship. Note that
this approach is preferable to leaving B_exec unbounded and having:
allow A B_exec:file <permissions>;
in policy because that would allow B's entrypoints to be used to
enter A. Similarly for _tmp or other related types.
3. If we have:
typebounds A B;
and an unbounded type T, then:
allow B T:file <permissions>;
will satisfy the bounds constraint iff:
allow A T:file <permissions>;
is allowed in policy.
The old logic would have been identical for this example.
4. If we have:
typebounds A B;
and an unbounded domain D, then:
allow D B:unix_stream_socket <permissions>;
is not subject to any bounds constraints under the new logic
because D is not bounded. This is desirable so that we can
allow a domain to e.g. connectto a child domain without having
to allow it to do the same to its parent.
The old logic would have required:
allow D A:unix_stream_socket <permissions>;
to also be allowed in policy.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
As per discussion in https://android-review.googlesource.com/#/c/221980,
we should be using #ifdef __APPLE__ rather than our own custom-defined
DARWIN for building on MacOS X.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
The current bounds checking of both source and target types
requires allowing any domain that has access to the child domain
to also have the same permissions to the parent, which is undesirable.
Drop the target bounds expansion and checking.
Making this change fully functional requires a corresponding kernel
change; this change only allows one to build policies that would
otherwise violate the bounds checking on target type. The kernel
change is required to allow the permissions at runtime.
Based on patch by Stephen Smalley.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
The attribute to type map is used to get all of the types that are
asociated with an attribute. To make neverallow and bounds checking
easier it was convienent to map a type to itself. However, CIL was
wrongly mapping an attribute to itself in addition to the types
associated with it. This caused type bounds checking to fail if the
parent was granted a permission through one attribute while the child
was granted the permission through another attribute.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Commit 3895fbbe0c ("selinux: Add support
for portcon dccp protocol") added support for the (portcon dccp ..)
statement. This fix will allow policy to be built on platforms
(see [1]) that do not have DCCP support by defining the IANA
assigned IP Protocol Number 33 to IPPROTO_DCCP.
[1] https://android-review.googlesource.com/#/c/219568/
Signed-off-by: Richard Haines <richard_c_haines@btinternet.com>
Commit 99fc177b "Add neverallow support for ioctl extended permissions"
first checks to see if the ioctl permission is granted, then checks to
see if the same source/target violates a neverallowed ioctl command.
Unfortunately this does not address the case where the ioctl permission
and extended permissions are granted on different attributes. Example,
the following will incorrectly cause a neverallow violation.
allow untrusted_app self:tcp_socket ioctl;
allowxperm domain domain:tcp_socket unpriv_sock_ioctls;
neverallowxperm untrusted_app domain:tcp_socket ~unpriv_sock_ioctls;
The fix is to enumerate over the source and target attributes when
looking for extended permission violations.
Note: The bug this addresses incorrectly asserts that a violation has
occurred. Actual neverallow violations are always caught.
Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Tested-by: William Roberts <william.c.roberts@intel.com>
For both neverallow and bounds checking keep neverallow and bounds
failures separate from program faults.
Have secilc exit with an error (and fail to build a binary policy)
when bounds checks fail.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
There are three improvements.
When calling cil_find_matching_avrule_in_ast(), one parameter specifies
whether to return a match of the exact same (not a duplicate) rule.
Since the target passed in is created and not actually in the tree
by making this parameter true an extra comparison can be avoided.
Currently, when printing a bounds violation trace, every match except
for the last one has only the parents of the rule printed. Only the
last rule has both its parents and the actual rule printed. Now the
parents and rule are printed for each match. This has the additional
benefit that if a match is not found (there should always be a match)
a seg fault will not occur.
To reduce the amount of error reporting, only print a trace of a
matching rule if it is different from the previous one.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
An attribute that has no types associated with it should still match
with itself, but ebitmap_match_any() will return false if there are
no bits set in either bitmap. The solution is to check to see if the
two datums passed into cil_type_match_any() are the same. This has
the additional advantage of providing a quick match anytime the
attributes are the same.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Other build scripts define -D_GNU_SOURCE. The Android build
system should too.
Fixes the following warning:
external/selinux/libsepol/cil/src/cil_mem.c:109:7: warning: implicit
declaration of function 'vasprintf' is invalid in C99
[-Wimplicit-function-declaration]
This adds CIL and checkpolicy support for the (portcon dccp ...)
statement. The kernel already handles name_bind and name_connect
permissions for the dccp_socket class.
Signed-off-by: Richard Haines <richard_c_haines@btinternet.com>
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
During resolution of classcommon statements (cil_resolve_classcommon),
we add the number of class common permissions to the values of the class
permissions. This way, the internal CIL values of the common permission
go from 0 to N, and the values of class permissions start at N+1 (where
N is the number of common permissions). When we reset a class due to
reresolve (cil_reset_class), we must then reverse this process by
subtracting the number of common permissions from the class permission
values.
However, there is a bug when resetting classes in which we subtract the
number of common permissions from the common permissions value rather
than the class permissions value. This means that class permissions
could be too high (since they are not reduced on reset) and common
permissions underflowed (since they are reduced, but should not be).
In most cases, this didn't actually matter since these permission values
aren't used when creating the binary. Additionally, we always access the
permissions via a hash table lookup or map, and then use whatever value
they have to set bits in bitmaps. As long as the bits in the bitmap
match the values, things work as expected. However, the one case where
these values do matter is if you use 'all' in a class permission set. In
this case, we enable bits 0 through number of permissions in a bitmap.
But because our permission values are all mixed up, these enabled bits
do not correspond to the permission values. This results in making it
look like no permissions were set in a class permission set, and the
rule is essentially ignored.
This patch fixes the bug so that the values of class permissions are
properly reset, allowing one to use 'all' in class permission sets in a
policy that reresolves.
Signed-off-by: Steve Lawrence <slawrence@tresys.com>
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
clang warns about variables which are used in a function body even
though they were marked __attribute__((unused)). For example:
interfaces.c:129:2: error: 'handle' was marked unused but was used
[-Werror,-Wused-but-marked-unused]
handle = NULL;
^
interfaces.c:233:2: error: 'handle' was marked unused but was used
[-Werror,-Wused-but-marked-unused]
handle = NULL;
^
Remove these warnings either by removing meaningless assigments or by
removing the attribute.
Signed-off-by: Nicolas Iooss <nicolas.iooss@m4x.org>
clang warns that __cil_permx_to_sepol_class_perms() return value, rc,
may be unitialized:
../cil/src/cil_binary.c:4188:9: error: variable 'rc' may be
uninitialized when used here [-Werror,-Wconditional-uninitialized]
return rc;
^~
../cil/src/cil_binary.c:4148:8: note: initialize the variable 'rc'
to silence this warning
int rc;
^
= 0
This theoretically happens when cil_expand_class(permx->obj) returns an
empty list.
Signed-off-by: Nicolas Iooss <nicolas.iooss@m4x.org>
Classes used in extended avrules and permissionxs must have an "ioctl"
permission. Add validation to ensure that is the case, or print an error
message otherwise.
Signed-off-by: Steve Lawrence <slawrence@tresys.com>
Add a new statement, neverallowx, which has the same syntax as allowx:
(neverallowx foo bar (ioctl file (range 0x2000 0x20FF)))
(allowx foo bar (ioctl file (0x20A0))) ; this fails
Much of the changes just move functions around or split functions up to
ease the sharing of avrule and avrulex comparisons with neverallows.
This refactoring also modifies the avrule struct to include a union of
either class permission information for standard avrules or extended
permission information for extended avrules, also done to support
sharing code.
This also changes assertion.c and avtab.c to allow
check_assertion_avtab_match to work with extended avrules.
Signed-off-by: Steve Lawrence <slawrence@tresys.com>
Currently neverallowxperm rules will be resolved correctly when
building policy, however they are not detectable when using tools
such as an updated version of setools. This patch will allow
these to be viewed in the same way as neverallow rules are in a
text based kernel policy file (e.g. policy.conf).
Signed-off-by: Richard Haines <richard_c_haines@btinternet.com>
Acked-by: Jeff Vander Stoep <jeffv@google.com>
Resolves https://github.com/SELinuxProject/cil/issues/3
An 'unordered' keyword provides the ability to append classes to the current
list of ordered classes. This allows users to not need knowledge of existing
classes when creating a class and fixes dependencies on classes when removing a
module. This enables userspace object managers with custom objects to be
modularized.
If a class is declared in both an unordered and ordered statement, then the
ordered statement will supercede the unordered declaration.
Example usage:
; Appends new_class to the existing list of classes
(class new_class ())
(classorder (unordered new_class))
Signed-off-by: Yuli Khodorkovskiy <ykhodorkovskiy@tresys.com>
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Neverallow rules for ioctl extended permissions will pass in two
cases:
1. If extended permissions exist for the source-target-class set
the test will pass if the neverallow values are excluded.
2. If extended permissions do not exist for the source-target-class
set the test will pass if the ioctl permission is not granted.
Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Acked-by: Nick Kralevich <nnk@google.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Add support for detecting recursive blockinherits, and print a trace of
the detected loop. Output will look something like this upon detection:
Recursive blockinherit found:
test.cil:42: block a
test.cil:43: blockinherit b
test.cil:36: block b
test.cil:37: blockinherit c
test.cil:39: block c
test.cil:40: blockinherit a
Additionally, improve support for detecting recursive macros/calls. Due
to the way calls are copied, the existing code only detected recursion
with call depth of three or more. Smaller depths, like
(macro m ()
(call m))
were not detected and caused a segfault. The callstack that was used for
this was not sufficient, so that is removed and replaced with a method
similar to the block recursion detection. A similar trace is also
displayed for recursive macros/calls.
Also, cleanup sidorder, classorder, catorder, sensorder, and in lists at
the end of resolve, fixing a potential memory leak if errors occur
during resolve.
Signed-off-by: Steve Lawrence <slawrence@tresys.com>
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
On older versions of gcc, an error is incorrectly given about
uninitialized variables. This will initialize the culprits.
Signed-off-by: Yuli Khodorkovskiy <ykhodorkovskiy@tresys.com>
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Fixes https://github.com/SELinuxProject/cil/issues/7.
This fixes a bug where cil_verify_classperms was executed on NULL
classperms lists. A check is now performed when verifying
classpermissions and classmap to ensure the classperms lists are not
empty.
Signed-off-by: Yuli Khodorkovskiy <ykhodorkovskiy@tresys.com>
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
This adds a userattribute statement that may be used in userroles and
constraints. The syntax is the same as typeattributset.
Also, disallow roleattributes where roles are accepted in contexts.
Specify a userattribute
(userattribute foo)
Add users to the set foo
(userattributeset foo (u1 u2))
Signed-off-by: Yuli Khodorkovskiy <ykhodorkovskiy@tresys.com>
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
