MFC r329994: mac_portacl(4): stop panicing INVARIANTS-enabled kernel by loading .ko
when kernel already has options MAC_PORTACL.

PR: 183817
Approved by: avg (mentor)

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Mark all SYSCTL_NODEs static that have no corresponding SYSCTL_DECLs.

The SYSCTL_NODE macro defines a list that stores all child-elements of
that node. If there's no SYSCTL_DECL macro anywhere else, there's no
reason why it shouldn't be static.

Mark MALLOC_DEFINEs static that have no corresponding MALLOC_DECLAREs.

This means that their use is restricted to a single C file.

Fix typos.

PR: bin/148894
Submitted by: olgeni

- Correct logic in if statement - we want to allocate temporary buffer
when someone is passing new rules, not when he only want to read them.
Because of this bug, even if the given rules were incorrect, they
ended up in rule_string.
- Add missing protection for rule_string when coping it.

Reviewed by: rwatson
MFC after: 1 week

Rather than having MAC policies explicitly declare what object types
they label, derive that information implicitly from the set of label
initializers in their policy operations set. This avoids a possible
class of programmer errors, while retaining the structure that
allows us to avoid allocating labels for objects that don't need
them. As before, we regenerate a global mask of labeled objects
each time a policy is loaded or unloaded, stored in mac_labeled.

Discussed with: csjp
Suggested by: Jacques Vidrine <nectar at apple.com>
Obtained from: TrustedBSD Project
Sponsored by: Apple, Inc.

Introduce two related changes to the TrustedBSD MAC Framework:

(1) Abstract interpreter vnode labeling in execve(2) and mac_execve(2)
so that the general exec code isn't aware of the details of
allocating, copying, and freeing labels, rather, simply passes in
a void pointer to start and stop functions that will be used by
the framework. This change will be MFC'd.

(2) Introduce a new flags field to the MAC_POLICY_SET(9) interface
allowing policies to declare which types of objects require label
allocation, initialization, and destruction, and define a set of
flags covering various supported object types (MPC_OBJECT_PROC,
MPC_OBJECT_VNODE, MPC_OBJECT_INPCB, ...). This change reduces the
overhead of compiling the MAC Framework into the kernel if policies
aren't loaded, or if policies require labels on only a small number
or even no object types. Each time a policy is loaded or unloaded,
we recalculate a mask of labeled object types across all policies
present in the system. Eliminate MAC_ALWAYS_LABEL_MBUF option as it
is no longer required.

MFC after: 1 week ((1) only)
Reviewed by: csjp
Obtained from: TrustedBSD Project
Sponsored by: Apple, Inc.

Add sbuf_new_auto as a shortcut for the very common case of creating a
completely dynamic sbuf.

Obtained from: Varnish
MFC after: 2 weeks

Consistently name functions for mac_<policy> as <policy>_whatever rather
than mac_<policy>_whatever, as this shortens the names and makes the code
a bit easier to read.

When dealing with label structures, name variables 'mb', 'ml', 'mm rather
than the longer 'mac_biba', 'mac_lomac', and 'mac_mls', likewise making
the code a little easier to read.

Obtained from: TrustedBSD Project

Merge first in a series of TrustedBSD MAC Framework KPI changes
from Mac OS X Leopard--rationalize naming for entry points to
the following general forms:

mac_<object>_<method/action>
mac_<object>_check_<method/action>

The previous naming scheme was inconsistent and mostly
reversed from the new scheme. Also, make object types more
consistent and remove spaces from object types that contain
multiple parts ("posix_sem" -> "posixsem") to make mechanical
parsing easier. Introduce a new "netinet" object type for
certain IPv4/IPv6-related methods. Also simplify, slightly,
some entry point names.

All MAC policy modules will need to be recompiled, and modules
not updates as part of this commit will need to be modified to
conform to the new KPI.

Sponsored by: SPARTA (original patches against Mac OS X)
Obtained from: TrustedBSD Project, Apple Computer

Eliminate now-unused SUSER_ALLOWJAIL arguments to priv_check_cred(); in
some cases, move to priv_check() if it was an operation on a thread and
no other flags were present.

Eliminate caller-side jail exception checking (also now-unused); jail
privilege exception code now goes solely in kern_jail.c.

We can't yet eliminate suser() due to some cases in the KAME code where
a privilege check is performed and then used in many different deferred
paths. Do, however, move those prototypes to priv.h.

Reviewed by: csjp
Obtained from: TrustedBSD Project

Apply variable name normalization to MAC policies: adopt global conventions
for the naming of variables associated with specific data structures.

Obtained from: TrustedBSD Project

More unnecessary include reduction.

Continue 7-CURRENT MAC Framework rearrangement and cleanup:

Don't perform a nested include of _label.h in mac.h, as mac.h now
describes only the user API to MAC, and _label.h defines the in-kernel
representation of MAC labels.

Remove mac.h includes from policies and MAC framework components that do
not use userspace MAC API definitions.

Add _KERNEL inclusion checks to mac_internal.h and mac_policy.h, as these
are kernel-only include files

Obtained from: TrustedBSD Project

Move src/sys/sys/mac_policy.h, the kernel interface between the MAC
Framework and security modules, to src/sys/security/mac/mac_policy.h,
completing the removal of kernel-only MAC Framework include files from
src/sys/sys. Update the MAC Framework and MAC policy modules. Delete
the old mac_policy.h.

Third party policy modules will need similar updating.

Obtained from: TrustedBSD Project

Sweep kernel replacing suser(9) calls with priv(9) calls, assigning
specific privilege names to a broad range of privileges. These may
require some future tweaking.

Sponsored by: nCircle Network Security, Inc.
Obtained from: TrustedBSD Project
Discussed on: arch@
Reviewed (at least in part) by: mlaier, jmg, pjd, bde, ceri,
Alex Lyashkov <umka at sevcity dot net>,
Skip Ford <skip dot ford at verizon dot net>,
Antoine Brodin <antoine dot brodin at laposte dot net>

Do allow jailed superuser to override the port ACL.

MFC after: 3 days
Submitted by: Michal Mertl <mime at traveller dot cz>

Normalize a significant number of kernel malloc type names:

- Prefer '_' to ' ', as it results in more easily parsed results in
memory monitoring tools such as vmstat.

- Remove punctuation that is incompatible with using memory type names
as file names, such as '/' characters.

- Disambiguate some collisions by adding subsystem prefixes to some
memory types.

- Generally prefer lower case to upper case.

- If the same type is defined in multiple architecture directories,
attempt to use the same name in additional cases.

Not all instances were caught in this change, so more work is required to
finish this conversion. Similar changes are required for UMA zone names.

Add a new sysctl/tunable to mac_portacl:

security.mac.portacl.autoport_exempt

This sysctl exempts to bind port '0' as long as IP_PORTRANGELOW hasn't
been set on the socket. This is quite useful as it allows applications
to use automatic binding without adding overly broad rules for the
binding of port 0. This sysctl defaults to enabled.

This is a slight variation on the patch submitted by the contributor.

MFC after: 2 weeks
Submitted by: Michal Mertl <mime at traveller dot cz>

Switch from using an sx lock to a mutex for the mac_portacl rule chain:
the sx lock was used previously because we might sleep allocating
additional memory by using auto-extending sbufs. However, we no longer
do this, instead retaining the user-submitted rule string, so mutexes
can be used instead. Annotate the reason for not using the sbuf-related
rule-to-string code with a comment.

Switch to using TAILQ_CONCAT() instead of manual list copying, as it's
O(1), reducing the rule replacement step under the mutex from O(2N) to
O(2).

Remove now uneeded vnode-related includes.

MFC after: 2 weeks

Remove dead code. (This loop counted the number of rules, but the count
was never used.)

Reported by: pjd
Approved by: rwatson

Pay attention to mac_portacl_enabled.

Submitted by: simon

Including <sys/stdint.h> is (almost?) universally only to be able to use
%j in printfs, so put a newsted include in <sys/systm.h> where the printf
prototype lives and save everybody else the trouble.

Do not depend on namespace pollution, explicitly include sys/sx.h

A cute yet small MAC policy that provides a simple ACL mechanism to
permit users and groups to bind ports for TCP or UDP, and is intended
to be combined with the recently committed support for
net.inet.ip.portrange.reservedhigh. The policy is twiddled using
sysctl(8). To use this module, you will need to compile in MAC
support, and probably set reservedhigh to 0, then twiddle
security.mac.portacl.rules to set things as desired. This policy
module only restricts ports explicitly bound using bind(), not
implicitly bound ports where the port number is selected by the
IP stack. It appears to work properly in my local configuration,
but needs more broad testing.

A sample policy might be:

# sysctl security.mac.portacl.rules="uid:425:tcp:80,uid:425:tcp:79"

This permits uid 425 to bind TCP sockets to ports 79 and 80. Currently
no distinction is made for incoming vs. outgoing ports with TCP,
although that would probably be easy to add.

Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories