This will allow for the parser to invalidate its caches separate of whether
the kernel policy version has changed. This can be desirable if a parser
bug is discovered, a new version the parser is shipped and we need to
force cache files to be regenerated.
Policy current stores a 32 bit version number in the header binary policy.
For newer policy (> v5 kernel abi) split this number into 3 separate
fields policy_version, parser_abi, kernel_abi.
If binary policy with a split version number is loaded to an older
kernel it will be correctly rejected as unsupported as those kernels
will see it as a none v5 version. For kernels that only support v5
policy on the kernel abi version is written.
The rules for policy versioning should be
policy_version:
Set by text policy language version. Parsers that don't understand
a specified version may fail, or drop rules they are unaware of.
parser_abi_version:
gets bumped when a userspace bug is discovered that requires policy be
recompiled. The policy version could be reset for each new kernel version
but since the parser needs to support multiple kernel versions tracking
this is extra work and should be avoided.
kernel_abi_version:
gets bumped when semantic changes need to be applied. Eg unix domain
sockets being mediated at connect.
the kernel abi version does not encapsulate all supported features.
As kernels could have different sets of patches supplied. Basic feature
support is determined by the policy_mediates() encoding in the policydb.
As such comparing cache features to kernel features is still needed
to determine if cached policy is best matched to the kernel.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
Tag start of entries in the policydb as being mediated. This makes
the start state for any class being mediated be none 0. The kernel
can detect this to determine whether the parser expected mediation
for the class.
This is just a way of encoding what features expect mediation within
the policydb it self so that a separate table isn't needed.
This is also used to indicate the new unix semantics for mediation of
unix domain sockets on connect should be applied.
Note: this does cause a fail open on situation on Ubuntu Saucy, which
did not properly indicate support. That is if a kernel using this patch
is installed on an Ubuntu Saucy system, unix domain socket mediation
on connect won't happen, instead the older behavior will be applied.
This won't cause policy failures as it is less strict than what
Ubuntu Saucy applies.
This is necessary so that AppArmor can properly function on older
userspaces without a compile time configuration on the kernel to determine
behavior. A kernel expecting this behavior will function correctly
with all old userspaces expect it will not enforce connect time mediation
on Ubuntu Saucy. However Ubuntu does not support Trusty (or newer)
kernels as backports to Saucy, so this does not break them.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
Make it more generic so that it can be shared with signals.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Steve Beattie <steve@nxnw.org>
Yes its seems pointless because these will eventually get replaced by
stl. But until then
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Steve Beattie <steve@nxnw.org>
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>
When a parser that is aware of dbus rules is running under a kernel
that is unaware of dbus rules, the parser should ignore the dbus rules
instead of attempting to load them into the kernel. Otherwise, the
kernel will reject the entire profile, leaving the application
unconfined.
Similar to what is done for mount rules, the features listed in
apparmorfs should be checked to see if dbus is supported under the
current kernel.
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: John Johansen <john.johansen@canonical.com>
Allow directories to be passed directly to the parser and handled instead
of needing an initscript to find the files in the directory.
eg. load all profiles in profiles dir
apparmor_parser -r /etc/apparmor.d/
eg. load all binary files in the cache dir
apparmor_parser -Br /etc/apparmor.d/cache/
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Steve Beattie <steve@nxnw.org>
This patch addresses a bunch of the compiler string conversion warnings
that were introduced with the C++-ification patch.
Signed-off-by: Steve Beattie <steve@nxnw.org>
Acked-by: Tyler Hicks <tyhicks@canonical.com>
Convert the codomain to a class, and the policy lists that store
codomains to stl containers instead of glibc twalk.
Signed-off-by: John Johansen <john.johansen@canonical.com>
[tyhicks: Merge with dbus changes and process_file_entries() cleanup]
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: Steve Beattie <steve@nxnw.org>
change_hat 1.4 was an experiement is more directly controlling change_hat
by adding hat rulles to the profile. It has not been used since the
original experiment (4 years). So remove it
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
Acked-by: Steve Beattie <steve@nxnw.org>
remove old dead code that used to fail compilation if regular expressions
where detected in the rules and the apparmor kernel module did not support
regular expression matching.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
Acked-by: Steve Beattie <steve@nxnw.org>
This conversion is nothing more than what is required to get it to
compile. Further improvements will come as the code is refactored.
Unfortunately due to C++ not supporting designated initializers, the auto
generation of af names needed to be reworked, and "netlink" and "unix"
domain socket keywords leaked in. Since these where going to be added in
separate patches I have not bothered to do the extra work to replace them
with a temporary place holder.
Signed-off-by: John Johansen <john.johansen@canonical.com>
[tyhicks: merged with dbus changes and memory leak fixes]
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
Acked-by: Steve Beattie <steve@nxnw.org>
Remove use of AARE_DFA as the alternate pcre matching engine was removed
years ago.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
Acked-by: Steve Beattie <steve@nxnw.org>
This patch moves the DUP_STRING macro to parser.h and modifies
it to accept a goto error target, that will be jumped to if the
call to strdup(3) fails. It also uses it in additional locations
where copying structures occurs, as well as detecting additional
cases where a structure duplication might have failed but not been
propagated outward.
Signed-off-by: Steve Beattie <steve@nxnw.org>
Acked-by: Tyler Hicks <tyhicks@canonical.com>
This patch implements the parsing of DBus rules.
It attempts to catch all corner cases, such as specifying a bind
permission with an interface conditional or specifying a subject name
conditional and a peer name conditional in the same rule.
It introduces the concept of conditional lists to the lexer and parser
in order to handle 'peer=(label=/usr/bin/foo name=com.foo.bar)', since
the existing list support in the lexer only supports a list of values.
The DBus rules are encoded as follows:
bus,name<bind_perm>,peer_label,path,interface,member<rw_perms>
Bind rules stop matching at name<bind_perm>. Note that name is used for
the subject name in bind rules and the peer name in rw rules. The
function new_dbus_entry() is what does the proper sanitization to make
sure that if a name conditional is specified, that it is the subject
name in the case of a bind rule or that it is the peer name in the case
of a rw rule.
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>
http://bugs.launchpad.net/bugs/979135
Currently a change_profile rule does not grant access to the
/proc/<pid>/attr/{current,exec} interfaces that are needed to perform
a change_profile or change_onexec, requiring that an explicit rule allowing
access to the interface be granted.
Make it so change_profile implies the necessary
/proc/@{PID}/attr/{current,exec} w,
rule just like the presence of hats does for change_hat
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-By: Steve Beattie <sbeattie@ubuntu.com>
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>
Newer versions of AppArmor use a features directory instead of a file
update the parser to use this to determine features and match string
This is just a first pass at this to get things up quickly. A much
more comprehensive rework that can parse and use the full information
set is needed.
Signed-off-by: John Johansen <john.johansen@canonical.com>
policydb is the new matching format, that combines the matching portions
of different rules into a single dfa/hfa. This patch only lays some ground
work it does not add encoding of any rules into the policydb
Signed-off-by: John Johansen <john.johansen@canonical.com>
value_list can be reused by conditionals and list values, so pull it out
and abstract it some more.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees@ubuntu.com>
The ability to set capabilities from a profile has been removed from the
kernel for several releases. Remove it from the parser as well.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees@ubuntu.com>
Currently the parser can not directly influence the lexer output. This
limits the grammar and also how the parser can be invoked. Allow the
parser to pass the next TOKEN that the lexer will return.
This is has two uses: It allows us to trick the bison parser into having
multiple start symbols, allowing us to say invoke the parser on an
individual network or file rule. It also allows the semantic analysis of
the parser to change the language recognized. This can be leveraged to
overcome some of the limitation of bison's LALR parse generator.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees@ubuntu.com>
There is a lot of duplication of code calling processqunquoted and
processquoted. Move all this code to use the new processid fn.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees@ubuntu.com>
This is a rather large rearrangement of how a subset of the parser global
variables are defined. Right now, there are unit tests built without
linking against parser_main.c. As a result, none of the globals defined in
parser_main.c could be used in the code that is built for unit tests
(misc, regex, symtab, variable). To get a clean build, either stubs needed
to be added to "#ifdef UNIT_TEST" blocks in each .c file, or we had to
depend on link-time optimizations that would throw out the unused routines.
First, this is a problem because all the compile-time warnings had to be
explicitly silenced, so reviewing the build logs becomes difficult on
failures, and we can potentially (in really unlucky situations) test
something that isn't actually part of the "real" parser.
Second, not all compilers will allow this kind of linking (e.g. mips gcc),
and the missing symbols at link time will fail the entire build even though
they're technically not needed.
To solve all of this, I've moved all of the global variables used in lex,
yacc, and main to parser_common.c, and adjusted the .h files. On top of
this, I made sure to fully link the tst builds so all symbols are resolved
(including aare lib) and removedonly tst build-log silencing (for now,
deferring to another future patchset to consolidate the build silencing).
Signed-off-by: Kees Cook <kees.cook@canonical.com>
Split out the aare_rule bits that encapsulate the convertion of apparmor
rules into the final compressed dfa.
This patch will not compile because of the it needs hfa to export an interface
but hfa is going to be split so just delay until hfa and transtable are
split and they can each export their own interface.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-By: Steve Beattie <sbeattie@ubuntu.com>
Older versions of the apparmor kernel patches didn't handle receiving
network tables of a larger size than expected.
Allow the parser to detect the kernel version and override the AF_MAX
value for those kernels.
This also replaces the hack using a hardcoded limit of 36 for kernels
missing the features flag.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees.cook@canonical.com>
Add the ability to specify the name and attachment of the profile
separately. It does not allow for the attachment specification to
begin with a variable however since variables in profile names is not
currently support this shouldn't be and issue.
Signed-off-by: John Johansen <john.johansen@canonical.com>
parsing, and precompilation of policy. This allows finding the most
recent text time stamp during parsing and this is then compared to
the cache file time stamp.
While this is slightly slower than the cache file check that only
validated against the profile file it fixes the bug where abstraction
updates do not cause the cache file to become invalid.
Instead of updating the profile name, allow a profile to have multiple
alternate names. Aliases are now added as alternate names and matched
through the xmatch dfa.
Alias was broken because it when an alias was made the old path was completely
removed and there was no way to specify it. Update it so aliases just add
an new duplicate rule instead.
This will allow turning on and off various debug dumps as needed.
Multiple dump options can be specified as needed by using multiple
options.
eg. apparmor_parser -D variables
apparmor_parser -D dfa-tree -D dfa-simple-tree
The help option has also been updated to take an optional argument
to display help about give parameters, currently only dump is supported.
eg. apparmor_parser -h # standard help
apparmor_parser -h=dump # dump info about --dump options
Also Enable the dfa expression tree dumps
