The features abi adds the ability to track the policy abi separate
from the kernel. This allow the compiler to determine whether policy
was developed with a certain feature in mind, eg. unix rules.
This allows the compiler to know whether it should tell the kernel to
enforce the feature if the kernel supports the rule but the policy
doesn't use it.
To find if a feature is supported we take the intersection of what is
supported by the policy and what is supported by the kernel.
Policy encoding features like whether to diff_encode policy are not
influenced by policy so these remain kernel only features.
In addition to adding the above intersection of policy rename
--compile-features to --policy-features as better represents what it
represents. --compile-features is left as a hidden item for backwards
compatibility.
MR: https://gitlab.com/apparmor/apparmor/-/merge_requests/491
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Steve Beattie <sbeattie@ubuntu.com>
Currently the NULL character is used as an out of band transition
for string/path elements. This works for them as the NULL character
is not valid for this data. However this does not work for binary
data that can contain a NULL character.
So far we have only dealt with fixed length fields of binary data
making the NULL separator either unnecessary.
However binary data like in the xattr match and mount data field are
variable length and can contain NULL characters. To deal with this
add the ability to specify out of band transitions, that can only
be triggered by code not input data.
The out of band transition can be used to separate variable length
data fields just as the NULL transition has been used to separate
variable length strings.
In the compressed hfa out of band transitions are expressed as a
negative offset from the states base. This leaves us room to expand
the character match range in the future if desired and on average
makes the range between the out of band transition and the input
transitions smaller than would be had if the out of band transition
had been stored after the valid input transitions.
Out of band transitions in the dfa will not break old kernels
that don't know about them, but they won't be able to trigger
the out of band transition match. So they should not be used unless
the kernel indicates that it supports them.
It should be noted that this patch only adds support for a single
out of band transition. If multiple out of band transitions are
required. It is trivial to extend.
- Add a tag indicating support in the kernel
- add a oob max range field to the dfa header so the kernel knows
what the max range that needs verifying is.
- extend oob generation fns to generate oob based on value instead
of a fixed -1.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Abstract af_unix socket names can contain a null character, however the
aare to pcre conversion explicitly disallows null characters because they
are not valid characters for pathnames. Fix this so that they type of
globbing is selectable.
this is a partial fix for
Bug: http://bugs.launchpad.net/bugs/1413410
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Steve Beattie <steve@nxnw.org>
Currently the apparmor parser warns about rules that are not enforced or
downgraded. This is a problem for distros that are not carrying the out of
tree kernel patches, as most profile loads result in warnings.
Change the behavior to not output a message unless a warn flag is passed.
This patch adds 2 different warn flags
--warn rule-downgraded # warn if a rule is downgraded
--warn rule-not-enforced # warn if a rule is not enforced at all
If the warnings are desired by default the flags can be set in the
parser.conf file.
v2 of patch
- update man page
- add --warn to usage statement
- make --quiet clear warn flags
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Steve Beattie <steve@nxnw.org>
