When resolving names, the struct cil_args_resolve is passed to the
various resolve functions. The field last_resolved_name is not used.
Remove the last_resolved_name field from struct cil_args_resolve.
Signed-off-by: James Carter <jwcart2@gmail.com>
Since cil_gen_node() is only called from declarations, the check to
determine if the node is a declaration is not needed, so remove it.
Signed-off-by: James Carter <jwcart2@gmail.com>
The function cil_tree_walk() has an argument that can be used by
the process_node helper function to tell cil_tree_walk() to skip
the node's sub-tree or the rest of the current branch. The constants
CIL_TREE_SKIP_NOTHING, CIL_TREE_SKIP_NEXT and CIL_TREE_SKIP_HEAD are
defined to be used by that argument.
Fixed two instances in the function __cil_build_ast_node_helper()
where the value 1 is used instead of the more informative
CIL_TREE_SKIP_NEXT.
Signed-off-by: James Carter <jwcart2@gmail.com>
Both tunableif and booleanif use conditional blocks (either true or
false). No ordering is imposed, so a false block can be first (or even
the only) block. Checks are made to ensure that the first and second
(if it exists) blocks are either true or false, but no checks are made
to ensure that there is only one true and/or one false block. If there
are more than one true or false block, only the first will be used and
the other will be ignored.
Create a function, cil_verify_conditional_blocks(), that gives an error
along with a message if more than one true or false block is specified
and call that function when building tunableif and booleanif blocks in
the AST.
Signed-off-by: James Carter <jwcart2@gmail.com>
Acked-by: Ondrej Mosnacek <omosnace@redhat.com>
Versioned duplicate symbols cause problems for LTO. These symbols were
introduced during the CIL integration several releases ago and were only
consumed by other SELinux userspace components.
Fixes: https://github.com/SELinuxProject/selinux/issues/245
Signed-off-by: Petr Lautrbach <plautrba@redhat.com>
When compiling SELinux userspace tools with -ftrapv (this option
generates traps for signed overflow on addition, subtraction,
multiplication operations, instead of silently wrapping around),
semodule crashes when running the tests from
scripts/ci/fedora-test-runner.sh in a Fedora 32 virtual machine:
[root@localhost selinux-testsuite]# make test
make -C policy load
make[1]: Entering directory '/root/selinux-testsuite/policy'
# Test for "expand-check = 0" in /etc/selinux/semanage.conf
# General policy build
make[2]: Entering directory '/root/selinux-testsuite/policy/test_policy'
Compiling targeted test_policy module
Creating targeted test_policy.pp policy package
rm tmp/test_policy.mod.fc
make[2]: Leaving directory '/root/selinux-testsuite/policy/test_policy'
# General policy load
domain_fd_use --> off
/usr/sbin/semodule -i test_policy/test_policy.pp test_mlsconstrain.cil test_overlay_defaultrange.cil test_add_levels.cil test_glblub.cil
make[1]: *** [Makefile:174: load] Aborted (core dumped)
Using "coredumpctl gdb" leads to the following strack trace:
(gdb) bt
#0 0x00007f608fe4fa25 in raise () from /lib64/libc.so.6
#1 0x00007f608fe38895 in abort () from /lib64/libc.so.6
#2 0x00007f6090028aca in __addvsi3.cold () from /lib64/libsepol.so.1
#3 0x00007f6090096f59 in __avrule_xperm_setrangebits (low=30, high=30, xperms=0x8b9eea0)
at ../cil/src/cil_binary.c:1551
#4 0x00007f60900970dd in __cil_permx_bitmap_to_sepol_xperms_list (xperms=0xb650a30, xperms_list=0x7ffce2653b18)
at ../cil/src/cil_binary.c:1596
#5 0x00007f6090097286 in __cil_avrulex_ioctl_to_policydb (k=0xb8ec200 "@\023\214\022\006", datum=0xb650a30,
args=0x239a640) at ../cil/src/cil_binary.c:1649
#6 0x00007f609003f1e5 in hashtab_map (h=0x41f8710, apply=0x7f60900971da <__cil_avrulex_ioctl_to_policydb>,
args=0x239a640) at hashtab.c:234
#7 0x00007f609009ea19 in cil_binary_create_allocated_pdb (db=0x2394f10, policydb=0x239a640)
at ../cil/src/cil_binary.c:4969
#8 0x00007f609009d19d in cil_binary_create (db=0x2394f10, policydb=0x7ffce2653d30) at ../cil/src/cil_binary.c:4329
#9 0x00007f609008ec23 in cil_build_policydb_create_pdb (db=0x2394f10, sepol_db=0x7ffce2653d30)
at ../cil/src/cil.c:631
#10 0x00007f608fff4bf3 in semanage_direct_commit () from /lib64/libsemanage.so.1
#11 0x00007f608fff9fae in semanage_commit () from /lib64/libsemanage.so.1
#12 0x0000000000403e2b in main (argc=7, argv=0x7ffce2655058) at semodule.c:753
(gdb) f 3
#3 0x00007f6090096f59 in __avrule_xperm_setrangebits (low=30, high=30, xperms=0x8b9eea0)
at ../cil/src/cil_binary.c:1551
1551 xperms->perms[i] |= XPERM_SETBITS(h) - XPERM_SETBITS(low);
A signed integer overflow therefore occurs in XPERM_SETBITS(h):
#define XPERM_SETBITS(x) ((1 << (x & 0x1f)) - 1)
This macro is expanded with h=31, so "(1 << 31) - 1" is computed:
* (1 << 31) = -0x80000000 is the lowest signed 32-bit integer value
* (1 << 31) - 1 overflows the capacity of a signed 32-bit integer and
results in 0x7fffffff (which is unsigned)
Using unsigned integers (with "1U") fixes the crash, as
(1U << 31) = 0x80000000U has no overflowing issues.
Signed-off-by: Nicolas Iooss <nicolas.iooss@m4x.org>
Acked-by: Petr Lautrbach <plautrba@redhat.com>
When classmaps used in a neverallow were being expanded during CIL
neverallow checking, an empty classmapping in the list of
classmappings for a classmap would cause the classmap expansion to
stop and the rest of the classmapping of the classmap to be ignored.
This would mean that not all of the classes and permissions associated
with the classmap would be used to check for a neverallow violation.
Do not end the expansion of a classmap when one classmapping is empty.
Reported-by: Jonathan Hettwer <j2468h@gmail.com>
Signed-off-by: James Carter <jwcart2@gmail.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
CIL was not correctly determining the depth of conditional expressions
which prevented it from giving an error when the max depth was exceeded.
This allowed invalid policy binaries to be created.
Validate the conditional expression using the same logic that is used
when evaluating a conditional expression. This includes checking the
depth of the expression.
Signed-off-by: James Carter <jwcart2@gmail.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
CIL was not correctly determining the depth of constraint expressions
which prevented it from giving an error when the max depth was exceeded.
This allowed invalid policy binaries with constraint expressions exceeding
the max depth to be created.
Validate the constraint expression using the same logic that is used
when reading the binary policy. This includes checking the depth of the
the expression.
Reported-by: Jonathan Hettwer <j2468h@gmail.com>
Signed-off-by: James Carter <jwcart2@gmail.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
In preparation to support a new policy format with a more optimal
representation of filename transition rules, this patch applies an
equivalent change from kernel commit c3a276111ea2 ("selinux: optimize
storage of filename transitions").
See the kernel commit's description [1] for the rationale behind this
representation. This change doesn't bring any measurable difference of
policy build performance (semodule -B) on Fedora.
[1] https://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux.git/commit/?id=c3a276111ea2572399281988b3129683e2a6b60b
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
CIL allows a type to be redeclared when using the multiple declarations
option ("-m" or "--muliple-decls"), but make it an error for an identifier
to be declared as both a type and an attribute.
Change the error message so that it always gives the location and flavor
of both declarations. The flavors will be the same in all other cases,
but in this case they explain why there is an error even if multiple
declartions are allowed.
Fixes: Commit fafe4c212b ("libsepol: cil: Add ability to redeclare types[attributes]")
Reported-by: Topi Miettinen <toiwoton@gmail.com>
Signed-off-by: James Carter <jwcart2@gmail.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Initialize the multiple_decls field when intializing the structure
cil_db.
Fixes: fafe4c212b ("libsepol: cil: Add ability to redeclare types[attributes]")
Reported-by: Topi Miettinen <toiwoton@gmail.com
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: James Carter <jwcart2@gmail.com>
This reverts commit 692716fc5f.
Other parts of the SELinux userspace depend on certain attributes,
such as node_type, exisiting and this change breaks those parts.
Before this patch can be reapplied, we need to identify the attributes
that must never be expanded and create a CIL module with the needed
expandtypeattribute statements (or something similar).
Signed-off-by: James Carter <jwcarter@gmail.com>
Fix issues like:
<inline asm>:1:1: error: unknown directive
.symver cil_build_policydb_pdb, cil_build_policydb@LIBSEPOL_1.0
Which was caused by the DISABLE_SYMVER define not being defined
for static, Mac or Android builds.
Acked-by: Joshua Brindle <joshua.brindle@crunchydata.com>
Signed-off-by: William Roberts <william.c.roberts@intel.com>
libsepol carried its own (outdated) copy of flask.h with the generated
security class and initial SID values for use by the policy
compiler and the forked copy of the security server code
leveraged by tools such as audit2why. Convert libsepol and
checkpolicy entirely to looking up class values from the policy,
remove the SECCLASS_* definitions from its flask.h header, and move
the header with its remaining initial SID definitions private to
libsepol. While we are here, fix the sepol_compute_sid() logic to
properly support features long since added to the policy and kernel,
although there are no users of it other than checkpolicy -d (debug)
and it is not exported to users of the shared library. There
are still some residual differences between the kernel logic and
libsepol.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Petr Lautrbach <plautrba@redhat.com>
The value attrs_expand_size == 1 removes all empty attributes, but it
also makes sense to expand all attributes that have only one type. This
removes some redundant rules (there is sometimes the same rule for the
type and the attribute) and reduces the number of attributes that the
kernel has to go through when looking up rules.
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: James Carter <jwcart2@gmail.com>
A parameter of a macro was only considered to be a duplicate if it
matched both the name and flavor of another parameter. While it is
true that CIL is able to differentiate between those two parameters,
there is no reason to use the same name for two macro parameters and
it is better to return an error for what is probably an error.
Remove the check of the flavors when checking for duplicate parameters.
Signed-off-by: James Carter <jwcart2@gmail.com>
Acked-by: Ondrej Mosnacek <omosnace@redhat.com>
Type transition file names are stored in a symbol table. Before the
name is added, the symbol table is searched to see if the name had
already been inserted. If it has, then the already existing datum is
returned. If it has not, then the name is added if either the
typetransition rule does not occur in a macro or the name is not one
of the macro parameters.
Checking for a previous insertion before checking if the name is a
macro parameter can cause a macro parameter to be treated as the
actual name if a previous type transition file name is the same as
the parameter.
Now check the name to see if it a macro paramter before checking for
its existence in the symbol table.
Signed-off-by: James Carter <jwcart2@gmail.com>
Acked-by: Ondrej Mosnacek <omosnace@redhat.com>
The filename_- and range_trans_table ancillary hash tables in
cil_binary.c just duplicate the final policydb content and can be simply
removed.
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
The classperms associated with each map class permission and with each
classpermissionset are verified in __cil_verify_classperms() which had
multiple problems with how it did the verification.
1) Verification was short-circuited when the first normal class is found.
The second classpermissionset statement below would not have been
verified.
(classpermission cp1)
(classpermissionset cp1 (CLASS (PERM)))
(classpermissionset cp1 cp2)
2) The classperms of a map class permission and classpermissionset were
not checked for being NULL before the function recursively called itself.
This would result in a segfault if the missing map or set was referred to
before the classmap or classpermission occured. This error was reported by
Dominick Grift (dominick.grift@defensec.nl).
These rules would cause a segfault.
(classmap cm1 (mp1))
(classmapping cm1 mp1 (cm2 (mp2)))
(classmap cm2 (mp2))
But an error would be produced for these rules.
(classmap cm1 (mp1))
(classmap cm2 (mp2))
(classmapping cm2 mp2 (cm1 (mp1)))
3) The loop detection logic was incomplete and could only detect a loop
with a certain statement ordering.
These rules would cause a stack overflow.
(classmap cm1 (mp1))
(classmapping cm1 mp1 (cm2 (mp2)))
(classmap cm2 (mp2))
(classmapping cm2 mp2 (cm3 (mp3)))
(classmap cm3 (mp3))
(classmapping cm3 mp3 (cm2 (mp2)))
Rewrote __cil_verify_classperms() to fix these errors.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Remove restrictions in libsepol and checkpolicy that required all
declared initial SIDs to be assigned a context. With this patch,
it is possible to build and load a policy that drops the sid <sidname>
<context> declarations for the unused initial SIDs. It is still
required to retain the sid <sidname> declarations (in the flask
definitions) in order to preserve the initial SID ordering/values.
The unused initial SIDs can be renamed, e.g. to add an unused_
prefix or similar, if desired, since the names used in the policy
are not stored in the kernel binary policy.
In CIL policies, the (sid ...) and (sidorder (...)) statements
must be left intact for compatibility but the (sidcontext ...)
statements for the unused initial SIDs can be omitted after this change.
With current kernels, if one removes an unused initial SID context
from policy, builds policy with this change applied and loads the
policy into the kernel, cat /sys/fs/selinux/initial_contexts/<sidname>
will show the unlabeled context. With the kernel patch to remove unused
initial SIDs, the /sys/fs/selinux/initial_contexts/<sidname>
file will not be created for unused initial SIDs in the first place.
NB If an unused initial SID was assigned a context different from
the unlabeled context in existing policy, then it is not safe to
remove that initial SID context from policy and reload policy on
the running kernel that was booted with the original policy. This
is because that kernel may have assigned that SID to various kernel
objects already and those objects will then be treated as having
the unlabeled context after the removal. In refpolicy, examples
of such initial SIDs are the "fs" SID and the "sysctl" SID. Even
though these initial SIDs are not directly used (in code) by the current
kernel, their contexts are being applied to filesystems and sysctl files by
policy and therefore the SIDs are being assigned to objects.
NB The "sysctl" SID was in use by the kernel up until
commit 8e6c96935fcc1ed3dbebc96fddfef3f2f2395afc ("security/selinux:
fix /proc/sys/ labeling) circa v2.6.39. Removing its context from
policy will cause sysctl(2) or /proc/sys accesses to end up
performing permission checks against the unlabeled context and
likely encounter denials for kernels < 2.6.39.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Commit 4459d635b8 ("libsepol: Remove cil_mem_error_handler() function
pointer") replaced cil_mem_error_handler usage with inline contents of
the default handler. However, it left over the header declaration and
two callers. Convert these as well and remove the header declaration.
This also fixes a build failure with -fno-common.
Fixes: 4459d635b8 ("libsepol: Remove cil_mem_error_handler() function pointer")
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
GCC 10 comes with -fno-common enabled by default - fix the CIL_KEY_*
global variables to be defined only once in cil.c and declared in the
header file correctly with the 'extern' keyword, so that other units
including the file don't generate duplicate definitions.
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
When copying an avrule with extended permissions (permx) in
cil_copy_avrule(), the check for a named permx checks the new permx
instead of the old one, so the check will always fail. This leads to a
segfault when trying to copy a named permx because there will be an
attempt to copy the nonexistent permx struct instead of the name of
the named permx.
Check whether the original is a named permx instead of the new one.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Since failing to resolve a statement in an optional block is normal,
only display messages about the statement failing to resolve and the
optional block being disabled at the highest verbosity level.
These messages are now only at log level CIL_INFO instead of CIL_WARN.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Use codespell (https://github.com/codespell-project/codespell) in order
to find many common misspellings that are present in English texts.
Signed-off-by: Nicolas Iooss <nicolas.iooss@m4x.org>
As reported by Nicolas Iooss (nicolas.iooss@m4x.org), static analyzers
have problems understanding that the default memory error handler does
not return since it is called through the cil_mem_error_handler()
function pointer. This results in a number of false positive warnings
about null pointer dereferencing.
Since the ability to set the cil_mem_error_handler() is only through
the function cil_set_mem_error_handler() which is never used and whose
definition is not in any header file, remove that function, remove the
use of cil_mem_error_handler() and directly in-line the contents of
the default handler, cil_default_mem_error_handler().
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
This patch is loosely based on a patch by Yuli Khodorkovskiy
<yuli@crunchydata.com> from June 13th, 2019.
Since any permission used in the policy should be defined, CIL
should return an error if it cannot resolve a permission used
in a policy. This was the original behavior of CIL.
The behavior was changed over three commits from July to November
2016 (See commits 46e157b47, da51020d6, and 2eefb20d8). The change
was motivated by Fedora trying to remove permissions from its
policy that were never upstreamed (ex/ process ptrace_child and
capability2 compromise_kernel). Local or third party modules
compiled with those permissions would break policy updates.
After three years it seems unlikely that we need to worry about
those local and third party modules and it is time for CIL to
give an error like it should.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Policy developers can set a default_range default to glblub and
computed contexts will be the intersection of the ranges of the
source and target contexts. This can be used by MLS userspace
object managers to find the range of clearances that two contexts
have in common. An example usage is computing a transition between
the network context and the context of a user logging into an MLS
application.
For example, one can add a default with
this cil:
(defaultrange db_table glblub)
or in te (base module only):
default_range db_table glblub;
and then test using the compute_create utility:
$ ./compute_create system_u:system_r:kernel_t:s0:c1,c2,c5-s0:c1.c20 system_u:system_r:kernel_t:s0:c0.c20-s0:c0.c36 db_table
system_u:object_r:kernel_t:s0:c1,c2,c5-s0:c1.c20
Some example range transitions are:
User Permitted Range | Network Device Label | Computed Label
---------------------|----------------------|----------------
s0-s1:c0.c12 | s0 | s0
s0-s1:c0.c12 | s0-s1:c0.c1023 | s0-s1:c0.c12
s0-s4:c0.c512 | s1-s1:c0.c1023 | s1-s1:c0.c512
s0-s15:c0,c2 | s4-s6:c0.c128 | s4-s6:c0,c2
s0-s4 | s2-s6 | s2-s4
s0-s4 | s5-s8 | INVALID
s5-s8 | s0-s4 | INVALID
Signed-off-by: Joshua Brindle <joshua.brindle@crunchydata.com>
Installing a cil module with invalid mlsconstrain syntax currently
results in a segfault. In the following module, the right-hand side of
the second operand of the OR is a list (mlstrustedobject):
$ cat test.cil
(class test (foo) )
(classorder (unordered test))
(mlsconstrain (test (foo))
(or
(dom h1 h2)
(eq t2 (mlstrustedobject))
)
)
$ sudo semodule -i test.cil
zsh: segmentation fault sudo semodule -i test.cil
This syntax is invalid and should error accordingly, rather than
segfaulting. This patch provides this syntax error for the same module:
$ sudo semodule -i test.cil
t1, t2, r1, r2, u1, u2 cannot be used on the left side with a list on the right side
Bad expression tree for constraint
Bad constrain declaration at /var/lib/selinux/mls/tmp/modules/400/test/cil:4
semodule: Failed!
Signed-off-by: Mike Palmiotto <mike.palmiotto@crunchydata.com>
When validatetrans rule is in CIL policy it errors with:
u3, r3, and t3 can only be used with mlsvalidatetrans rules
Will now resolve these examples:
(validatetrans binder (and (and (eq t1 t1_t) (eq t2 t2_t)) (eq t3 t3_t)))
(mlsvalidatetrans file (and (and (eq t1 t1_t) (eq t2 t2_t))
(and (eq t3 t3_t) (domby h1 h2))))
Signed-off-by: Richard Haines <richard_c_haines@btinternet.com>
Most of the users of ebitmap_for_each_bit() macro only care for the set
bits, so introduce a new ebitmap_for_each_positive_bit() macro that
skips the unset bits. Replace uses of ebitmap_for_each_bit() with the
new macro where appropriate.
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
clang's static analyze reports a use-after-free in
__cil_expr_to_string(), when __cil_expr_to_string_helper() does not
modify its third parameter (variable s1 here) in this loop:
for (curr = curr->next; curr; curr = curr->next) {
__cil_expr_to_string_helper(curr, flavor, &s1);
cil_asprintf(&c2, "%s %s", c1, s1);
free(c1);
free(s1);
c1 = c2;
}
Silence this warning by making sure s1 is always NULL at the beginning
of every iteration of the loop.
Signed-off-by: Nicolas Iooss <nicolas.iooss@m4x.org>
These were reported by Petr Lautrbach (plautrba@redhat.com) and this
patch was based on his patch with only a few changes.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
In cil_tree_print_expr(), "rc < 0" is equivalent to "rc != 0" but
clang's static analyzer does not know about this. Help it.
Signed-off-by: Nicolas Iooss <nicolas.iooss@m4x.org>
Improve the processing of netifcon, genfscon, ibpkeycon, ibendportcon,
portcon, nodecon, fsuse, filecon, iomemcon, ioportcon, pcidevicecon,
and devicetreecon rules.
If the multiple-decls option is not used then report errors if duplicate
context rules are found. If it is used then remove duplicate context rules
and report errors when two rules are identical except for the context.
This also changes the ordering of portcon and filecon rules. The protocol
of portcon rules will be compared if the port numbers are the same and the
path strings of filecon rules will be compared if the number of meta
characters, the stem length, string length and file types are the same.
Based on an initial patch by Pierre-Hugues Husson (phh@phh.me)
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
This commit resolves conflicts in values of expandattribute statements
in policy language and expandtypeattribute in CIL.
For example, these statements resolve to false in policy language:
expandattribute hal_audio true;
expandattribute hal_audio false;
Similarly, in CIL these also resolve to false.
(expandtypeattribute (hal_audio) true)
(expandtypeattribute (hal_audio) false)
A warning will be issued on this conflict.
Motivation
When Android combines multiple .cil files from system.img and vendor.img
it's possible to have conflicting expandattribute statements.
This change deals with this scenario by resolving the value of the
corresponding expandtypeattribute to false. The rationale behind this
override is that true is used for reduce run-time lookups, while
false is used for tests which must pass.
Signed-off-by: Tri Vo <trong@android.com>
Acked-by: Jeff Vander Stoep <jeffv@google.com>
Acked-by: William Roberts <william.c.roberts@intel.com>
Acked-by: James Carter <jwcart2@tycho.nsa.gov>
cil_tree_print_expr() calls cil_expr_to_string() in order to compute a
string expression into expr_str. If this function fails, expr_str is
left unitialized but its value is dereferenced with:
cil_log(CIL_INFO, "%s)", expr_str);
Prevent such an issue by checking cil_expr_to_string()'s return value
before using expr_str.
This issue has been found with clang's static analyzer.
Signed-off-by: Nicolas Iooss <nicolas.iooss@m4x.org>
Daniel Cashman <dcashman@android.com> discovered the following:
When using cil_db multiple_decls, the different cil_attribute nodes
all point to the same underlying cil_attribute struct. This leads
to problems, though, when modifying the used value in the struct.
__cil_post_db_attr() changes the value of the field to based on
the output of cil_typeattribute_used(), for use later in
cil_typeattribute_to_policydb and cil_typeattribute_to_bitmap, but
due to the multiple declarations, cil_typeattribute_used() could be
called again by a second node. In this second call, the value used
is the modifed value of CIL_TRUE or CIL_FALSE, not the flags actually
needed. This could result in the field being reset again, to an
incorrect CIL_FALSE value.
Add the field "keep" to struct cil_typeattributeset, set its value
using cil_typeattribute_used(), and use it when determining whether
the attribute is to be kept or if it should be expanded.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
cil_gen_node() has been using its argument "db" since commit
fafe4c212b ("libsepol: cil: Add ability to redeclare
types[attributes]"). Drop attribute "unused" on this argument.
Signed-off-by: Nicolas Iooss <nicolas.iooss@m4x.org>
cil_defaults_to_policy() defines its third argument as non-const "char
*kind" even though it is called with literal strings. This makes gcc
report the following warning when compiling with -Wwrite-strings:
../cil/src/cil_policy.c: In function ‘cil_gen_policy’:
../cil/src/cil_policy.c:1931:60: error: passing argument 3 of
‘cil_defaults_to_policy’ discards ‘const’ qualifier from pointer
target type [-Werror=discarded-qualifiers]
cil_defaults_to_policy(out, lists[CIL_LIST_DEFAULT_USER],
"default_user");
^~~~~~~~~~~~~~
Signed-off-by: Nicolas Iooss <nicolas.iooss@m4x.org>
Since commit 67b410e80f ("libsepol/cil: Keep attributes used by
generated attributes in neverallow rules") gcc reports the following
warning when building libsepol:
../cil/src/cil_post.c: In function
‘__cil_post_db_neverallow_attr_helper’:
../cil/src/cil_post.c:1322:17: error: unused variable ‘db’
[-Werror=unused-variable]
struct cil_db *db = extra_args;
^~
Signed-off-by: Nicolas Iooss <nicolas.iooss@m4x.org>
In order to reduce policy size, CIL removes attributes that are not used
by a policy rule in the generated binary policy. However, CIL keeps
attributes used by neverallow rules (which are checked at compile time
and not in the binary policy) even if the attribute is not used anywhere
else in the policy. This behavior is useful to Google who pulls neverallow
rules out of the original policy.conf for compatibility testing, but
converts the policy.conf to CIL and uses the CIL compiler to generate
policy. Without this behavior, the generated binary policy might not have
an attribute referred to by one of the neverallow rules used for testing.
The one exception to this behavior is for attributes generated in
module_to_cil (these have an "_typeattr_" in the middle of their name).
Since these attributes are only created because CIL does not allow a
type expression in an AV rule, they are removed if they only appear in
a neverallow rule (which is the case for most of them) or if the
option to expand generated attributes (-G or --expand-generated) is
specified for secilc when compiling the policy.
Removing generated attributes causes a problem, however, if the type
expression that the generated attribute is replacing uses an attribute
that is removed. In this case, the original neverallow rule will refer
to an attribute that does not exist in the generated binary policy.
Now any non-generated attribute used in a typeattributeset rule for a
generated attribute which is used in a neverallow rule will be treated
like it was used in a neverallow rule.
This does not change the behavior of an expandtypeattribute rule for
the attribute. That rule, if it exists, will take precedence.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Modify cil_gen_node() to check to see if the cil_db supports multiple
declarations, and if so, to check whether or not the
repeated symbol is eligible to share the existing, already-stored datum. The
only types considered so far are CIL_TYPE and CIL_TYPEATTRIBUTE, both of
which intall empty datums during AST building, so they automatically return
true.
Test: Build policy with multilpe type and attribute declarations, and
without. Policies are binary-identical.
Signed-off-by: Dan Cashman <dcashman@android.com>
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
