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freebsd/sys/kern/kern_mac.c

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/*-
* Copyright (c) 1999, 2000, 2001, 2002 Robert N. M. Watson
* Copyright (c) 2001 Ilmar S. Habibulin
* Copyright (c) 2001, 2002, 2003 Networks Associates Technology, Inc.
* All rights reserved.
*
* This software was developed by Robert Watson and Ilmar Habibulin for the
* TrustedBSD Project.
*
* This software was developed for the FreeBSD Project in part by Network
* Associates Laboratories, the Security Research Division of Network
* Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"),
* as part of the DARPA CHATS research program.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
2003-06-11 00:56:59 +00:00
/*
* Framework for extensible kernel access control. Kernel and userland
* interface to the framework, policy registration and composition.
*/
2003-06-11 00:56:59 +00:00
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_mac.h"
#include "opt_devfs.h"
#include <sys/param.h>
#include <sys/condvar.h>
#include <sys/extattr.h>
#include <sys/imgact.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mutex.h>
#include <sys/mac.h>
#include <sys/module.h>
#include <sys/proc.h>
#include <sys/sbuf.h>
#include <sys/systm.h>
#include <sys/sysproto.h>
#include <sys/sysent.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/file.h>
#include <sys/namei.h>
#include <sys/socket.h>
#include <sys/pipe.h>
#include <sys/socketvar.h>
#include <sys/sysctl.h>
#include <vm/vm.h>
#include <vm/pmap.h>
#include <vm/vm_map.h>
#include <vm/vm_object.h>
#include <sys/mac_policy.h>
#include <fs/devfs/devfs.h>
#include <net/bpfdesc.h>
#include <net/if.h>
#include <net/if_var.h>
#include <netinet/in.h>
#include <netinet/ip_var.h>
#include <security/mac/mac_internal.h>
#ifdef MAC
/*
* Declare that the kernel provides MAC support, version 1. This permits
* modules to refuse to be loaded if the necessary support isn't present,
* even if it's pre-boot.
*/
MODULE_VERSION(kernel_mac_support, 1);
SYSCTL_NODE(_security, OID_AUTO, mac, CTLFLAG_RW, 0,
"TrustedBSD MAC policy controls");
#if MAC_MAX_SLOTS > 32
#error "MAC_MAX_SLOTS too large"
#endif
static unsigned int mac_max_slots = MAC_MAX_SLOTS;
static unsigned int mac_slot_offsets_free = (1 << MAC_MAX_SLOTS) - 1;
SYSCTL_UINT(_security_mac, OID_AUTO, max_slots, CTLFLAG_RD,
&mac_max_slots, 0, "");
/*
* Has the kernel started generating labeled objects yet? All read/write
* access to this variable is serialized during the boot process. Following
* the end of serialization, we don't update this flag; no locking.
*/
int mac_late = 0;
Move MAC label storage for mbufs into m_tags from the m_pkthdr structure, returning some additional room in the first mbuf in a chain, and avoiding feature-specific contents in the mbuf header. To do this: - Modify mbuf_to_label() to extract the tag, returning NULL if not found. - Introduce mac_init_mbuf_tag() which does most of the work mac_init_mbuf() used to do, except on an m_tag rather than an mbuf. - Scale back mac_init_mbuf() to perform m_tag allocation and invoke mac_init_mbuf_tag(). - Replace mac_destroy_mbuf() with mac_destroy_mbuf_tag(), since m_tag's are now GC'd deep in the m_tag/mbuf code rather than at a higher level when mbufs are directly free()'d. - Add mac_copy_mbuf_tag() to support m_copy_pkthdr() and related notions. - Generally change all references to mbuf labels so that they use mbuf_to_label() rather than &mbuf->m_pkthdr.label. This required no changes in the MAC policies (yay!). - Tweak mbuf release routines to not call mac_destroy_mbuf(), tag destruction takes care of it for us now. - Remove MAC magic from m_copy_pkthdr() and m_move_pkthdr() -- the existing m_tag support does all this for us. Note that we can no longer just zero the m_tag list on the target mbuf, rather, we have to delete the chain because m_tag's will already be hung off freshly allocated mbuf's. - Tweak m_tag copying routines so that if we're copying a MAC m_tag, we don't do a binary copy, rather, we initialize the new storage and do a deep copy of the label. - Remove use of MAC_FLAG_INITIALIZED in a few bizarre places having to do with mbuf header copies previously. - When an mbuf is copied in ip_input(), we no longer need to explicitly copy the label because it will get handled by the m_tag code now. - No longer any weird handling of MAC labels in if_loop.c during header copies. - Add MPC_LOADTIME_FLAG_LABELMBUFS flag to Biba, MLS, mac_test. In mac_test, handle the label==NULL case, since it can be dynamically loaded. In order to improve performance with this change, introduce the notion of "lazy MAC label allocation" -- only allocate m_tag storage for MAC labels if we're running with a policy that uses MAC labels on mbufs. Policies declare this intent by setting the MPC_LOADTIME_FLAG_LABELMBUFS flag in their load-time flags field during declaration. Note: this opens up the possibility of post-boot policy modules getting back NULL slot entries even though they have policy invariants of non-NULL slot entries, as the policy might have been loaded after the mbuf was allocated, leaving the mbuf without label storage. Policies that cannot handle this case must be declared as NOTLATE, or must be modified. - mac_labelmbufs holds the current cumulative status as to whether any policies require mbuf labeling or not. This is updated whenever the active policy set changes by the function mac_policy_updateflags(). The function iterates the list and checks whether any have the flag set. Write access to this variable is protected by the policy list; read access is currently not protected for performance reasons. This might change if it causes problems. - Add MAC_POLICY_LIST_ASSERT_EXCLUSIVE() to permit the flags update function to assert appropriate locks. - This makes allocation in mac_init_mbuf() conditional on the flag. Reviewed by: sam Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-04-14 20:39:06 +00:00
/*
* Flag to indicate whether or not we should allocate label storage for
* new mbufs. Since most dynamic policies we currently work with don't
* rely on mbuf labeling, try to avoid paying the cost of mtag allocation
* unless specifically notified of interest. One result of this is
* that if a dynamically loaded policy requests mbuf labels, it must
* be able to deal with a NULL label being returned on any mbufs that
* were already in flight when the policy was loaded. Since the policy
* already has to deal with uninitialized labels, this probably won't
* be a problem. Note: currently no locking. Will this be a problem?
*/
#ifndef MAC_ALWAYS_LABEL_MBUF
int mac_labelmbufs = 0;
Move MAC label storage for mbufs into m_tags from the m_pkthdr structure, returning some additional room in the first mbuf in a chain, and avoiding feature-specific contents in the mbuf header. To do this: - Modify mbuf_to_label() to extract the tag, returning NULL if not found. - Introduce mac_init_mbuf_tag() which does most of the work mac_init_mbuf() used to do, except on an m_tag rather than an mbuf. - Scale back mac_init_mbuf() to perform m_tag allocation and invoke mac_init_mbuf_tag(). - Replace mac_destroy_mbuf() with mac_destroy_mbuf_tag(), since m_tag's are now GC'd deep in the m_tag/mbuf code rather than at a higher level when mbufs are directly free()'d. - Add mac_copy_mbuf_tag() to support m_copy_pkthdr() and related notions. - Generally change all references to mbuf labels so that they use mbuf_to_label() rather than &mbuf->m_pkthdr.label. This required no changes in the MAC policies (yay!). - Tweak mbuf release routines to not call mac_destroy_mbuf(), tag destruction takes care of it for us now. - Remove MAC magic from m_copy_pkthdr() and m_move_pkthdr() -- the existing m_tag support does all this for us. Note that we can no longer just zero the m_tag list on the target mbuf, rather, we have to delete the chain because m_tag's will already be hung off freshly allocated mbuf's. - Tweak m_tag copying routines so that if we're copying a MAC m_tag, we don't do a binary copy, rather, we initialize the new storage and do a deep copy of the label. - Remove use of MAC_FLAG_INITIALIZED in a few bizarre places having to do with mbuf header copies previously. - When an mbuf is copied in ip_input(), we no longer need to explicitly copy the label because it will get handled by the m_tag code now. - No longer any weird handling of MAC labels in if_loop.c during header copies. - Add MPC_LOADTIME_FLAG_LABELMBUFS flag to Biba, MLS, mac_test. In mac_test, handle the label==NULL case, since it can be dynamically loaded. In order to improve performance with this change, introduce the notion of "lazy MAC label allocation" -- only allocate m_tag storage for MAC labels if we're running with a policy that uses MAC labels on mbufs. Policies declare this intent by setting the MPC_LOADTIME_FLAG_LABELMBUFS flag in their load-time flags field during declaration. Note: this opens up the possibility of post-boot policy modules getting back NULL slot entries even though they have policy invariants of non-NULL slot entries, as the policy might have been loaded after the mbuf was allocated, leaving the mbuf without label storage. Policies that cannot handle this case must be declared as NOTLATE, or must be modified. - mac_labelmbufs holds the current cumulative status as to whether any policies require mbuf labeling or not. This is updated whenever the active policy set changes by the function mac_policy_updateflags(). The function iterates the list and checks whether any have the flag set. Write access to this variable is protected by the policy list; read access is currently not protected for performance reasons. This might change if it causes problems. - Add MAC_POLICY_LIST_ASSERT_EXCLUSIVE() to permit the flags update function to assert appropriate locks. - This makes allocation in mac_init_mbuf() conditional on the flag. Reviewed by: sam Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-04-14 20:39:06 +00:00
#endif
#ifdef MAC_DEBUG
SYSCTL_NODE(_security_mac, OID_AUTO, debug, CTLFLAG_RW, 0,
"TrustedBSD MAC debug info");
SYSCTL_NODE(_security_mac_debug, OID_AUTO, counters, CTLFLAG_RW, 0,
"TrustedBSD MAC object counters");
static unsigned int nmactemp;
SYSCTL_UINT(_security_mac_debug_counters, OID_AUTO, temp, CTLFLAG_RD,
&nmactemp, 0, "number of temporary labels in use");
#endif
static int mac_policy_register(struct mac_policy_conf *mpc);
static int mac_policy_unregister(struct mac_policy_conf *mpc);
MALLOC_DEFINE(M_MACTEMP, "mactemp", "MAC temporary label storage");
/*
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
* mac_static_policy_list holds a list of policy modules that are not
* loaded while the system is "live", and cannot be unloaded. These
* policies can be invoked without holding the busy count.
*
* mac_policy_list stores the list of dynamic policies. A busy count is
* maintained for the list, stored in mac_policy_busy. The busy count
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
* is protected by mac_policy_mtx; the list may be modified only
* while the busy count is 0, requiring that the lock be held to
* prevent new references to the list from being acquired. For almost
* all operations, incrementing the busy count is sufficient to
* guarantee consistency, as the list cannot be modified while the
* busy count is elevated. For a few special operations involving a
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
* change to the list of active policies, the mtx itself must be held.
* A condition variable, mac_policy_cv, is used to signal potential
* exclusive consumers that they should try to acquire the lock if a
* first attempt at exclusive access fails.
*/
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
static struct mtx mac_policy_mtx;
static struct cv mac_policy_cv;
static int mac_policy_count;
struct mac_policy_list_head mac_policy_list;
struct mac_policy_list_head mac_static_policy_list;
/*
* We manually invoke WITNESS_WARN() to allow Witness to generate
* warnings even if we don't end up ever triggering the wait at
* run-time. The consumer of the exclusive interface must not hold
* any locks (other than potentially Giant) since we may sleep for
* long (potentially indefinite) periods of time waiting for the
* framework to become quiescent so that a policy list change may
* be made.
*/
void
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
mac_policy_grab_exclusive(void)
{
WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
"mac_policy_grab_exclusive() at %s:%d", __FILE__, __LINE__);
mtx_lock(&mac_policy_mtx);
while (mac_policy_count != 0)
cv_wait(&mac_policy_cv, &mac_policy_mtx);
}
void
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
mac_policy_assert_exclusive(void)
{
mtx_assert(&mac_policy_mtx, MA_OWNED);
KASSERT(mac_policy_count == 0,
("mac_policy_assert_exclusive(): not exclusive"));
}
Move MAC label storage for mbufs into m_tags from the m_pkthdr structure, returning some additional room in the first mbuf in a chain, and avoiding feature-specific contents in the mbuf header. To do this: - Modify mbuf_to_label() to extract the tag, returning NULL if not found. - Introduce mac_init_mbuf_tag() which does most of the work mac_init_mbuf() used to do, except on an m_tag rather than an mbuf. - Scale back mac_init_mbuf() to perform m_tag allocation and invoke mac_init_mbuf_tag(). - Replace mac_destroy_mbuf() with mac_destroy_mbuf_tag(), since m_tag's are now GC'd deep in the m_tag/mbuf code rather than at a higher level when mbufs are directly free()'d. - Add mac_copy_mbuf_tag() to support m_copy_pkthdr() and related notions. - Generally change all references to mbuf labels so that they use mbuf_to_label() rather than &mbuf->m_pkthdr.label. This required no changes in the MAC policies (yay!). - Tweak mbuf release routines to not call mac_destroy_mbuf(), tag destruction takes care of it for us now. - Remove MAC magic from m_copy_pkthdr() and m_move_pkthdr() -- the existing m_tag support does all this for us. Note that we can no longer just zero the m_tag list on the target mbuf, rather, we have to delete the chain because m_tag's will already be hung off freshly allocated mbuf's. - Tweak m_tag copying routines so that if we're copying a MAC m_tag, we don't do a binary copy, rather, we initialize the new storage and do a deep copy of the label. - Remove use of MAC_FLAG_INITIALIZED in a few bizarre places having to do with mbuf header copies previously. - When an mbuf is copied in ip_input(), we no longer need to explicitly copy the label because it will get handled by the m_tag code now. - No longer any weird handling of MAC labels in if_loop.c during header copies. - Add MPC_LOADTIME_FLAG_LABELMBUFS flag to Biba, MLS, mac_test. In mac_test, handle the label==NULL case, since it can be dynamically loaded. In order to improve performance with this change, introduce the notion of "lazy MAC label allocation" -- only allocate m_tag storage for MAC labels if we're running with a policy that uses MAC labels on mbufs. Policies declare this intent by setting the MPC_LOADTIME_FLAG_LABELMBUFS flag in their load-time flags field during declaration. Note: this opens up the possibility of post-boot policy modules getting back NULL slot entries even though they have policy invariants of non-NULL slot entries, as the policy might have been loaded after the mbuf was allocated, leaving the mbuf without label storage. Policies that cannot handle this case must be declared as NOTLATE, or must be modified. - mac_labelmbufs holds the current cumulative status as to whether any policies require mbuf labeling or not. This is updated whenever the active policy set changes by the function mac_policy_updateflags(). The function iterates the list and checks whether any have the flag set. Write access to this variable is protected by the policy list; read access is currently not protected for performance reasons. This might change if it causes problems. - Add MAC_POLICY_LIST_ASSERT_EXCLUSIVE() to permit the flags update function to assert appropriate locks. - This makes allocation in mac_init_mbuf() conditional on the flag. Reviewed by: sam Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-04-14 20:39:06 +00:00
void
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
mac_policy_release_exclusive(void)
{
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
KASSERT(mac_policy_count == 0,
("mac_policy_release_exclusive(): not exclusive"));
mtx_unlock(&mac_policy_mtx);
cv_signal(&mac_policy_cv);
}
void
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
mac_policy_list_busy(void)
{
mtx_lock(&mac_policy_mtx);
mac_policy_count++;
mtx_unlock(&mac_policy_mtx);
}
int
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
mac_policy_list_conditional_busy(void)
{
int ret;
mtx_lock(&mac_policy_mtx);
if (!LIST_EMPTY(&mac_policy_list)) {
mac_policy_count++;
ret = 1;
} else
ret = 0;
mtx_unlock(&mac_policy_mtx);
return (ret);
}
void
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
mac_policy_list_unbusy(void)
{
mtx_lock(&mac_policy_mtx);
mac_policy_count--;
KASSERT(mac_policy_count >= 0, ("MAC_POLICY_LIST_LOCK"));
if (mac_policy_count == 0)
cv_signal(&mac_policy_cv);
mtx_unlock(&mac_policy_mtx);
}
/*
* Initialize the MAC subsystem, including appropriate SMP locks.
*/
static void
mac_init(void)
{
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
LIST_INIT(&mac_static_policy_list);
LIST_INIT(&mac_policy_list);
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
mtx_init(&mac_policy_mtx, "mac_policy_mtx", NULL, MTX_DEF);
cv_init(&mac_policy_cv, "mac_policy_cv");
}
/*
* For the purposes of modules that want to know if they were loaded
* "early", set the mac_late flag once we've processed modules either
* linked into the kernel, or loaded before the kernel startup.
*/
static void
mac_late_init(void)
{
mac_late = 1;
}
Move MAC label storage for mbufs into m_tags from the m_pkthdr structure, returning some additional room in the first mbuf in a chain, and avoiding feature-specific contents in the mbuf header. To do this: - Modify mbuf_to_label() to extract the tag, returning NULL if not found. - Introduce mac_init_mbuf_tag() which does most of the work mac_init_mbuf() used to do, except on an m_tag rather than an mbuf. - Scale back mac_init_mbuf() to perform m_tag allocation and invoke mac_init_mbuf_tag(). - Replace mac_destroy_mbuf() with mac_destroy_mbuf_tag(), since m_tag's are now GC'd deep in the m_tag/mbuf code rather than at a higher level when mbufs are directly free()'d. - Add mac_copy_mbuf_tag() to support m_copy_pkthdr() and related notions. - Generally change all references to mbuf labels so that they use mbuf_to_label() rather than &mbuf->m_pkthdr.label. This required no changes in the MAC policies (yay!). - Tweak mbuf release routines to not call mac_destroy_mbuf(), tag destruction takes care of it for us now. - Remove MAC magic from m_copy_pkthdr() and m_move_pkthdr() -- the existing m_tag support does all this for us. Note that we can no longer just zero the m_tag list on the target mbuf, rather, we have to delete the chain because m_tag's will already be hung off freshly allocated mbuf's. - Tweak m_tag copying routines so that if we're copying a MAC m_tag, we don't do a binary copy, rather, we initialize the new storage and do a deep copy of the label. - Remove use of MAC_FLAG_INITIALIZED in a few bizarre places having to do with mbuf header copies previously. - When an mbuf is copied in ip_input(), we no longer need to explicitly copy the label because it will get handled by the m_tag code now. - No longer any weird handling of MAC labels in if_loop.c during header copies. - Add MPC_LOADTIME_FLAG_LABELMBUFS flag to Biba, MLS, mac_test. In mac_test, handle the label==NULL case, since it can be dynamically loaded. In order to improve performance with this change, introduce the notion of "lazy MAC label allocation" -- only allocate m_tag storage for MAC labels if we're running with a policy that uses MAC labels on mbufs. Policies declare this intent by setting the MPC_LOADTIME_FLAG_LABELMBUFS flag in their load-time flags field during declaration. Note: this opens up the possibility of post-boot policy modules getting back NULL slot entries even though they have policy invariants of non-NULL slot entries, as the policy might have been loaded after the mbuf was allocated, leaving the mbuf without label storage. Policies that cannot handle this case must be declared as NOTLATE, or must be modified. - mac_labelmbufs holds the current cumulative status as to whether any policies require mbuf labeling or not. This is updated whenever the active policy set changes by the function mac_policy_updateflags(). The function iterates the list and checks whether any have the flag set. Write access to this variable is protected by the policy list; read access is currently not protected for performance reasons. This might change if it causes problems. - Add MAC_POLICY_LIST_ASSERT_EXCLUSIVE() to permit the flags update function to assert appropriate locks. - This makes allocation in mac_init_mbuf() conditional on the flag. Reviewed by: sam Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-04-14 20:39:06 +00:00
/*
* After the policy list has changed, walk the list to update any global
* flags. Currently, we support only one flag, and it's conditionally
* defined; as a result, the entire function is conditional. Eventually,
* the #else case might also iterate across the policies.
Move MAC label storage for mbufs into m_tags from the m_pkthdr structure, returning some additional room in the first mbuf in a chain, and avoiding feature-specific contents in the mbuf header. To do this: - Modify mbuf_to_label() to extract the tag, returning NULL if not found. - Introduce mac_init_mbuf_tag() which does most of the work mac_init_mbuf() used to do, except on an m_tag rather than an mbuf. - Scale back mac_init_mbuf() to perform m_tag allocation and invoke mac_init_mbuf_tag(). - Replace mac_destroy_mbuf() with mac_destroy_mbuf_tag(), since m_tag's are now GC'd deep in the m_tag/mbuf code rather than at a higher level when mbufs are directly free()'d. - Add mac_copy_mbuf_tag() to support m_copy_pkthdr() and related notions. - Generally change all references to mbuf labels so that they use mbuf_to_label() rather than &mbuf->m_pkthdr.label. This required no changes in the MAC policies (yay!). - Tweak mbuf release routines to not call mac_destroy_mbuf(), tag destruction takes care of it for us now. - Remove MAC magic from m_copy_pkthdr() and m_move_pkthdr() -- the existing m_tag support does all this for us. Note that we can no longer just zero the m_tag list on the target mbuf, rather, we have to delete the chain because m_tag's will already be hung off freshly allocated mbuf's. - Tweak m_tag copying routines so that if we're copying a MAC m_tag, we don't do a binary copy, rather, we initialize the new storage and do a deep copy of the label. - Remove use of MAC_FLAG_INITIALIZED in a few bizarre places having to do with mbuf header copies previously. - When an mbuf is copied in ip_input(), we no longer need to explicitly copy the label because it will get handled by the m_tag code now. - No longer any weird handling of MAC labels in if_loop.c during header copies. - Add MPC_LOADTIME_FLAG_LABELMBUFS flag to Biba, MLS, mac_test. In mac_test, handle the label==NULL case, since it can be dynamically loaded. In order to improve performance with this change, introduce the notion of "lazy MAC label allocation" -- only allocate m_tag storage for MAC labels if we're running with a policy that uses MAC labels on mbufs. Policies declare this intent by setting the MPC_LOADTIME_FLAG_LABELMBUFS flag in their load-time flags field during declaration. Note: this opens up the possibility of post-boot policy modules getting back NULL slot entries even though they have policy invariants of non-NULL slot entries, as the policy might have been loaded after the mbuf was allocated, leaving the mbuf without label storage. Policies that cannot handle this case must be declared as NOTLATE, or must be modified. - mac_labelmbufs holds the current cumulative status as to whether any policies require mbuf labeling or not. This is updated whenever the active policy set changes by the function mac_policy_updateflags(). The function iterates the list and checks whether any have the flag set. Write access to this variable is protected by the policy list; read access is currently not protected for performance reasons. This might change if it causes problems. - Add MAC_POLICY_LIST_ASSERT_EXCLUSIVE() to permit the flags update function to assert appropriate locks. - This makes allocation in mac_init_mbuf() conditional on the flag. Reviewed by: sam Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-04-14 20:39:06 +00:00
*/
static void
mac_policy_updateflags(void)
{
#ifndef MAC_ALWAYS_LABEL_MBUF
struct mac_policy_conf *tmpc;
Move MAC label storage for mbufs into m_tags from the m_pkthdr structure, returning some additional room in the first mbuf in a chain, and avoiding feature-specific contents in the mbuf header. To do this: - Modify mbuf_to_label() to extract the tag, returning NULL if not found. - Introduce mac_init_mbuf_tag() which does most of the work mac_init_mbuf() used to do, except on an m_tag rather than an mbuf. - Scale back mac_init_mbuf() to perform m_tag allocation and invoke mac_init_mbuf_tag(). - Replace mac_destroy_mbuf() with mac_destroy_mbuf_tag(), since m_tag's are now GC'd deep in the m_tag/mbuf code rather than at a higher level when mbufs are directly free()'d. - Add mac_copy_mbuf_tag() to support m_copy_pkthdr() and related notions. - Generally change all references to mbuf labels so that they use mbuf_to_label() rather than &mbuf->m_pkthdr.label. This required no changes in the MAC policies (yay!). - Tweak mbuf release routines to not call mac_destroy_mbuf(), tag destruction takes care of it for us now. - Remove MAC magic from m_copy_pkthdr() and m_move_pkthdr() -- the existing m_tag support does all this for us. Note that we can no longer just zero the m_tag list on the target mbuf, rather, we have to delete the chain because m_tag's will already be hung off freshly allocated mbuf's. - Tweak m_tag copying routines so that if we're copying a MAC m_tag, we don't do a binary copy, rather, we initialize the new storage and do a deep copy of the label. - Remove use of MAC_FLAG_INITIALIZED in a few bizarre places having to do with mbuf header copies previously. - When an mbuf is copied in ip_input(), we no longer need to explicitly copy the label because it will get handled by the m_tag code now. - No longer any weird handling of MAC labels in if_loop.c during header copies. - Add MPC_LOADTIME_FLAG_LABELMBUFS flag to Biba, MLS, mac_test. In mac_test, handle the label==NULL case, since it can be dynamically loaded. In order to improve performance with this change, introduce the notion of "lazy MAC label allocation" -- only allocate m_tag storage for MAC labels if we're running with a policy that uses MAC labels on mbufs. Policies declare this intent by setting the MPC_LOADTIME_FLAG_LABELMBUFS flag in their load-time flags field during declaration. Note: this opens up the possibility of post-boot policy modules getting back NULL slot entries even though they have policy invariants of non-NULL slot entries, as the policy might have been loaded after the mbuf was allocated, leaving the mbuf without label storage. Policies that cannot handle this case must be declared as NOTLATE, or must be modified. - mac_labelmbufs holds the current cumulative status as to whether any policies require mbuf labeling or not. This is updated whenever the active policy set changes by the function mac_policy_updateflags(). The function iterates the list and checks whether any have the flag set. Write access to this variable is protected by the policy list; read access is currently not protected for performance reasons. This might change if it causes problems. - Add MAC_POLICY_LIST_ASSERT_EXCLUSIVE() to permit the flags update function to assert appropriate locks. - This makes allocation in mac_init_mbuf() conditional on the flag. Reviewed by: sam Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-04-14 20:39:06 +00:00
int labelmbufs;
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
mac_policy_assert_exclusive();
Move MAC label storage for mbufs into m_tags from the m_pkthdr structure, returning some additional room in the first mbuf in a chain, and avoiding feature-specific contents in the mbuf header. To do this: - Modify mbuf_to_label() to extract the tag, returning NULL if not found. - Introduce mac_init_mbuf_tag() which does most of the work mac_init_mbuf() used to do, except on an m_tag rather than an mbuf. - Scale back mac_init_mbuf() to perform m_tag allocation and invoke mac_init_mbuf_tag(). - Replace mac_destroy_mbuf() with mac_destroy_mbuf_tag(), since m_tag's are now GC'd deep in the m_tag/mbuf code rather than at a higher level when mbufs are directly free()'d. - Add mac_copy_mbuf_tag() to support m_copy_pkthdr() and related notions. - Generally change all references to mbuf labels so that they use mbuf_to_label() rather than &mbuf->m_pkthdr.label. This required no changes in the MAC policies (yay!). - Tweak mbuf release routines to not call mac_destroy_mbuf(), tag destruction takes care of it for us now. - Remove MAC magic from m_copy_pkthdr() and m_move_pkthdr() -- the existing m_tag support does all this for us. Note that we can no longer just zero the m_tag list on the target mbuf, rather, we have to delete the chain because m_tag's will already be hung off freshly allocated mbuf's. - Tweak m_tag copying routines so that if we're copying a MAC m_tag, we don't do a binary copy, rather, we initialize the new storage and do a deep copy of the label. - Remove use of MAC_FLAG_INITIALIZED in a few bizarre places having to do with mbuf header copies previously. - When an mbuf is copied in ip_input(), we no longer need to explicitly copy the label because it will get handled by the m_tag code now. - No longer any weird handling of MAC labels in if_loop.c during header copies. - Add MPC_LOADTIME_FLAG_LABELMBUFS flag to Biba, MLS, mac_test. In mac_test, handle the label==NULL case, since it can be dynamically loaded. In order to improve performance with this change, introduce the notion of "lazy MAC label allocation" -- only allocate m_tag storage for MAC labels if we're running with a policy that uses MAC labels on mbufs. Policies declare this intent by setting the MPC_LOADTIME_FLAG_LABELMBUFS flag in their load-time flags field during declaration. Note: this opens up the possibility of post-boot policy modules getting back NULL slot entries even though they have policy invariants of non-NULL slot entries, as the policy might have been loaded after the mbuf was allocated, leaving the mbuf without label storage. Policies that cannot handle this case must be declared as NOTLATE, or must be modified. - mac_labelmbufs holds the current cumulative status as to whether any policies require mbuf labeling or not. This is updated whenever the active policy set changes by the function mac_policy_updateflags(). The function iterates the list and checks whether any have the flag set. Write access to this variable is protected by the policy list; read access is currently not protected for performance reasons. This might change if it causes problems. - Add MAC_POLICY_LIST_ASSERT_EXCLUSIVE() to permit the flags update function to assert appropriate locks. - This makes allocation in mac_init_mbuf() conditional on the flag. Reviewed by: sam Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-04-14 20:39:06 +00:00
labelmbufs = 0;
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
LIST_FOREACH(tmpc, &mac_static_policy_list, mpc_list) {
if (tmpc->mpc_loadtime_flags & MPC_LOADTIME_FLAG_LABELMBUFS)
labelmbufs++;
}
Move MAC label storage for mbufs into m_tags from the m_pkthdr structure, returning some additional room in the first mbuf in a chain, and avoiding feature-specific contents in the mbuf header. To do this: - Modify mbuf_to_label() to extract the tag, returning NULL if not found. - Introduce mac_init_mbuf_tag() which does most of the work mac_init_mbuf() used to do, except on an m_tag rather than an mbuf. - Scale back mac_init_mbuf() to perform m_tag allocation and invoke mac_init_mbuf_tag(). - Replace mac_destroy_mbuf() with mac_destroy_mbuf_tag(), since m_tag's are now GC'd deep in the m_tag/mbuf code rather than at a higher level when mbufs are directly free()'d. - Add mac_copy_mbuf_tag() to support m_copy_pkthdr() and related notions. - Generally change all references to mbuf labels so that they use mbuf_to_label() rather than &mbuf->m_pkthdr.label. This required no changes in the MAC policies (yay!). - Tweak mbuf release routines to not call mac_destroy_mbuf(), tag destruction takes care of it for us now. - Remove MAC magic from m_copy_pkthdr() and m_move_pkthdr() -- the existing m_tag support does all this for us. Note that we can no longer just zero the m_tag list on the target mbuf, rather, we have to delete the chain because m_tag's will already be hung off freshly allocated mbuf's. - Tweak m_tag copying routines so that if we're copying a MAC m_tag, we don't do a binary copy, rather, we initialize the new storage and do a deep copy of the label. - Remove use of MAC_FLAG_INITIALIZED in a few bizarre places having to do with mbuf header copies previously. - When an mbuf is copied in ip_input(), we no longer need to explicitly copy the label because it will get handled by the m_tag code now. - No longer any weird handling of MAC labels in if_loop.c during header copies. - Add MPC_LOADTIME_FLAG_LABELMBUFS flag to Biba, MLS, mac_test. In mac_test, handle the label==NULL case, since it can be dynamically loaded. In order to improve performance with this change, introduce the notion of "lazy MAC label allocation" -- only allocate m_tag storage for MAC labels if we're running with a policy that uses MAC labels on mbufs. Policies declare this intent by setting the MPC_LOADTIME_FLAG_LABELMBUFS flag in their load-time flags field during declaration. Note: this opens up the possibility of post-boot policy modules getting back NULL slot entries even though they have policy invariants of non-NULL slot entries, as the policy might have been loaded after the mbuf was allocated, leaving the mbuf without label storage. Policies that cannot handle this case must be declared as NOTLATE, or must be modified. - mac_labelmbufs holds the current cumulative status as to whether any policies require mbuf labeling or not. This is updated whenever the active policy set changes by the function mac_policy_updateflags(). The function iterates the list and checks whether any have the flag set. Write access to this variable is protected by the policy list; read access is currently not protected for performance reasons. This might change if it causes problems. - Add MAC_POLICY_LIST_ASSERT_EXCLUSIVE() to permit the flags update function to assert appropriate locks. - This makes allocation in mac_init_mbuf() conditional on the flag. Reviewed by: sam Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-04-14 20:39:06 +00:00
LIST_FOREACH(tmpc, &mac_policy_list, mpc_list) {
if (tmpc->mpc_loadtime_flags & MPC_LOADTIME_FLAG_LABELMBUFS)
labelmbufs++;
}
mac_labelmbufs = (labelmbufs != 0);
#endif
}
/*
* Allow MAC policy modules to register during boot, etc.
*/
int
mac_policy_modevent(module_t mod, int type, void *data)
{
struct mac_policy_conf *mpc;
int error;
error = 0;
mpc = (struct mac_policy_conf *) data;
switch (type) {
case MOD_LOAD:
if (mpc->mpc_loadtime_flags & MPC_LOADTIME_FLAG_NOTLATE &&
mac_late) {
printf("mac_policy_modevent: can't load %s policy "
"after booting\n", mpc->mpc_name);
error = EBUSY;
break;
}
error = mac_policy_register(mpc);
break;
case MOD_UNLOAD:
/* Don't unregister the module if it was never registered. */
if ((mpc->mpc_runtime_flags & MPC_RUNTIME_FLAG_REGISTERED)
!= 0)
error = mac_policy_unregister(mpc);
else
error = 0;
break;
default:
break;
}
return (error);
}
static int
mac_policy_register(struct mac_policy_conf *mpc)
{
struct mac_policy_conf *tmpc;
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
int error, slot, static_entry;
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
error = 0;
/*
* We don't technically need exclusive access while !mac_late,
* but hold it for assertion consistency.
*/
mac_policy_grab_exclusive();
/*
* If the module can potentially be unloaded, or we're loading
* late, we have to stick it in the non-static list and pay
* an extra performance overhead. Otherwise, we can pay a
* light locking cost and stick it in the static list.
*/
static_entry = (!mac_late &&
!(mpc->mpc_loadtime_flags & MPC_LOADTIME_FLAG_UNLOADOK));
if (static_entry) {
LIST_FOREACH(tmpc, &mac_static_policy_list, mpc_list) {
if (strcmp(tmpc->mpc_name, mpc->mpc_name) == 0) {
error = EEXIST;
goto out;
}
}
} else {
LIST_FOREACH(tmpc, &mac_policy_list, mpc_list) {
if (strcmp(tmpc->mpc_name, mpc->mpc_name) == 0) {
error = EEXIST;
goto out;
}
}
}
if (mpc->mpc_field_off != NULL) {
slot = ffs(mac_slot_offsets_free);
if (slot == 0) {
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
error = ENOMEM;
goto out;
}
slot--;
mac_slot_offsets_free &= ~(1 << slot);
*mpc->mpc_field_off = slot;
}
mpc->mpc_runtime_flags |= MPC_RUNTIME_FLAG_REGISTERED;
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
/*
* If we're loading a MAC module after the framework has
* initialized, it has to go into the dynamic list. If
* we're loading it before we've finished initializing,
* it can go into the static list with weaker locker
* requirements.
*/
if (static_entry)
LIST_INSERT_HEAD(&mac_static_policy_list, mpc, mpc_list);
else
LIST_INSERT_HEAD(&mac_policy_list, mpc, mpc_list);
/* Per-policy initialization. */
if (mpc->mpc_ops->mpo_init != NULL)
(*(mpc->mpc_ops->mpo_init))(mpc);
Move MAC label storage for mbufs into m_tags from the m_pkthdr structure, returning some additional room in the first mbuf in a chain, and avoiding feature-specific contents in the mbuf header. To do this: - Modify mbuf_to_label() to extract the tag, returning NULL if not found. - Introduce mac_init_mbuf_tag() which does most of the work mac_init_mbuf() used to do, except on an m_tag rather than an mbuf. - Scale back mac_init_mbuf() to perform m_tag allocation and invoke mac_init_mbuf_tag(). - Replace mac_destroy_mbuf() with mac_destroy_mbuf_tag(), since m_tag's are now GC'd deep in the m_tag/mbuf code rather than at a higher level when mbufs are directly free()'d. - Add mac_copy_mbuf_tag() to support m_copy_pkthdr() and related notions. - Generally change all references to mbuf labels so that they use mbuf_to_label() rather than &mbuf->m_pkthdr.label. This required no changes in the MAC policies (yay!). - Tweak mbuf release routines to not call mac_destroy_mbuf(), tag destruction takes care of it for us now. - Remove MAC magic from m_copy_pkthdr() and m_move_pkthdr() -- the existing m_tag support does all this for us. Note that we can no longer just zero the m_tag list on the target mbuf, rather, we have to delete the chain because m_tag's will already be hung off freshly allocated mbuf's. - Tweak m_tag copying routines so that if we're copying a MAC m_tag, we don't do a binary copy, rather, we initialize the new storage and do a deep copy of the label. - Remove use of MAC_FLAG_INITIALIZED in a few bizarre places having to do with mbuf header copies previously. - When an mbuf is copied in ip_input(), we no longer need to explicitly copy the label because it will get handled by the m_tag code now. - No longer any weird handling of MAC labels in if_loop.c during header copies. - Add MPC_LOADTIME_FLAG_LABELMBUFS flag to Biba, MLS, mac_test. In mac_test, handle the label==NULL case, since it can be dynamically loaded. In order to improve performance with this change, introduce the notion of "lazy MAC label allocation" -- only allocate m_tag storage for MAC labels if we're running with a policy that uses MAC labels on mbufs. Policies declare this intent by setting the MPC_LOADTIME_FLAG_LABELMBUFS flag in their load-time flags field during declaration. Note: this opens up the possibility of post-boot policy modules getting back NULL slot entries even though they have policy invariants of non-NULL slot entries, as the policy might have been loaded after the mbuf was allocated, leaving the mbuf without label storage. Policies that cannot handle this case must be declared as NOTLATE, or must be modified. - mac_labelmbufs holds the current cumulative status as to whether any policies require mbuf labeling or not. This is updated whenever the active policy set changes by the function mac_policy_updateflags(). The function iterates the list and checks whether any have the flag set. Write access to this variable is protected by the policy list; read access is currently not protected for performance reasons. This might change if it causes problems. - Add MAC_POLICY_LIST_ASSERT_EXCLUSIVE() to permit the flags update function to assert appropriate locks. - This makes allocation in mac_init_mbuf() conditional on the flag. Reviewed by: sam Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-04-14 20:39:06 +00:00
mac_policy_updateflags();
printf("Security policy loaded: %s (%s)\n", mpc->mpc_fullname,
mpc->mpc_name);
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
out:
mac_policy_release_exclusive();
return (error);
}
static int
mac_policy_unregister(struct mac_policy_conf *mpc)
{
/*
* If we fail the load, we may get a request to unload. Check
* to see if we did the run-time registration, and if not,
* silently succeed.
*/
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
mac_policy_grab_exclusive();
if ((mpc->mpc_runtime_flags & MPC_RUNTIME_FLAG_REGISTERED) == 0) {
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
mac_policy_release_exclusive();
return (0);
}
#if 0
/*
* Don't allow unloading modules with private data.
*/
if (mpc->mpc_field_off != NULL) {
MAC_POLICY_LIST_UNLOCK();
return (EBUSY);
}
#endif
/*
* Only allow the unload to proceed if the module is unloadable
* by its own definition.
*/
if ((mpc->mpc_loadtime_flags & MPC_LOADTIME_FLAG_UNLOADOK) == 0) {
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
mac_policy_release_exclusive();
return (EBUSY);
}
if (mpc->mpc_ops->mpo_destroy != NULL)
(*(mpc->mpc_ops->mpo_destroy))(mpc);
LIST_REMOVE(mpc, mpc_list);
mpc->mpc_runtime_flags &= ~MPC_RUNTIME_FLAG_REGISTERED;
Move MAC label storage for mbufs into m_tags from the m_pkthdr structure, returning some additional room in the first mbuf in a chain, and avoiding feature-specific contents in the mbuf header. To do this: - Modify mbuf_to_label() to extract the tag, returning NULL if not found. - Introduce mac_init_mbuf_tag() which does most of the work mac_init_mbuf() used to do, except on an m_tag rather than an mbuf. - Scale back mac_init_mbuf() to perform m_tag allocation and invoke mac_init_mbuf_tag(). - Replace mac_destroy_mbuf() with mac_destroy_mbuf_tag(), since m_tag's are now GC'd deep in the m_tag/mbuf code rather than at a higher level when mbufs are directly free()'d. - Add mac_copy_mbuf_tag() to support m_copy_pkthdr() and related notions. - Generally change all references to mbuf labels so that they use mbuf_to_label() rather than &mbuf->m_pkthdr.label. This required no changes in the MAC policies (yay!). - Tweak mbuf release routines to not call mac_destroy_mbuf(), tag destruction takes care of it for us now. - Remove MAC magic from m_copy_pkthdr() and m_move_pkthdr() -- the existing m_tag support does all this for us. Note that we can no longer just zero the m_tag list on the target mbuf, rather, we have to delete the chain because m_tag's will already be hung off freshly allocated mbuf's. - Tweak m_tag copying routines so that if we're copying a MAC m_tag, we don't do a binary copy, rather, we initialize the new storage and do a deep copy of the label. - Remove use of MAC_FLAG_INITIALIZED in a few bizarre places having to do with mbuf header copies previously. - When an mbuf is copied in ip_input(), we no longer need to explicitly copy the label because it will get handled by the m_tag code now. - No longer any weird handling of MAC labels in if_loop.c during header copies. - Add MPC_LOADTIME_FLAG_LABELMBUFS flag to Biba, MLS, mac_test. In mac_test, handle the label==NULL case, since it can be dynamically loaded. In order to improve performance with this change, introduce the notion of "lazy MAC label allocation" -- only allocate m_tag storage for MAC labels if we're running with a policy that uses MAC labels on mbufs. Policies declare this intent by setting the MPC_LOADTIME_FLAG_LABELMBUFS flag in their load-time flags field during declaration. Note: this opens up the possibility of post-boot policy modules getting back NULL slot entries even though they have policy invariants of non-NULL slot entries, as the policy might have been loaded after the mbuf was allocated, leaving the mbuf without label storage. Policies that cannot handle this case must be declared as NOTLATE, or must be modified. - mac_labelmbufs holds the current cumulative status as to whether any policies require mbuf labeling or not. This is updated whenever the active policy set changes by the function mac_policy_updateflags(). The function iterates the list and checks whether any have the flag set. Write access to this variable is protected by the policy list; read access is currently not protected for performance reasons. This might change if it causes problems. - Add MAC_POLICY_LIST_ASSERT_EXCLUSIVE() to permit the flags update function to assert appropriate locks. - This makes allocation in mac_init_mbuf() conditional on the flag. Reviewed by: sam Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-04-14 20:39:06 +00:00
mac_policy_updateflags();
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
mac_policy_release_exclusive();
printf("Security policy unload: %s (%s)\n", mpc->mpc_fullname,
mpc->mpc_name);
return (0);
}
/*
* Define an error value precedence, and given two arguments, selects the
* value with the higher precedence.
*/
int
mac_error_select(int error1, int error2)
{
/* Certain decision-making errors take top priority. */
if (error1 == EDEADLK || error2 == EDEADLK)
return (EDEADLK);
/* Invalid arguments should be reported where possible. */
if (error1 == EINVAL || error2 == EINVAL)
return (EINVAL);
/* Precedence goes to "visibility", with both process and file. */
if (error1 == ESRCH || error2 == ESRCH)
return (ESRCH);
if (error1 == ENOENT || error2 == ENOENT)
return (ENOENT);
/* Precedence goes to DAC/MAC protections. */
if (error1 == EACCES || error2 == EACCES)
return (EACCES);
/* Precedence goes to privilege. */
if (error1 == EPERM || error2 == EPERM)
return (EPERM);
/* Precedence goes to error over success; otherwise, arbitrary. */
if (error1 != 0)
return (error1);
return (error2);
}
void
mac_init_label(struct label *label)
{
bzero(label, sizeof(*label));
label->l_flags = MAC_FLAG_INITIALIZED;
}
void
mac_destroy_label(struct label *label)
{
KASSERT(label->l_flags & MAC_FLAG_INITIALIZED,
("destroying uninitialized label"));
bzero(label, sizeof(*label));
/* implicit: label->l_flags &= ~MAC_FLAG_INITIALIZED; */
}
int
mac_check_structmac_consistent(struct mac *mac)
{
if (mac->m_buflen < 0 ||
mac->m_buflen > MAC_MAX_LABEL_BUF_LEN)
return (EINVAL);
return (0);
}
int
__mac_get_pid(struct thread *td, struct __mac_get_pid_args *uap)
{
char *elements, *buffer;
struct mac mac;
struct proc *tproc;
struct ucred *tcred;
int error;
2002-12-14 01:56:26 +00:00
error = copyin(uap->mac_p, &mac, sizeof(mac));
if (error)
return (error);
error = mac_check_structmac_consistent(&mac);
if (error)
return (error);
tproc = pfind(uap->pid);
if (tproc == NULL)
return (ESRCH);
tcred = NULL; /* Satisfy gcc. */
error = p_cansee(td, tproc);
if (error == 0)
tcred = crhold(tproc->p_ucred);
PROC_UNLOCK(tproc);
if (error)
return (error);
elements = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK);
error = copyinstr(mac.m_string, elements, mac.m_buflen, NULL);
if (error) {
free(elements, M_MACTEMP);
crfree(tcred);
return (error);
}
buffer = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK | M_ZERO);
error = mac_externalize_cred_label(&tcred->cr_label, elements,
buffer, mac.m_buflen, M_WAITOK);
if (error == 0)
error = copyout(buffer, mac.m_string, strlen(buffer)+1);
free(buffer, M_MACTEMP);
free(elements, M_MACTEMP);
crfree(tcred);
return (error);
}
/*
* MPSAFE
*/
int
__mac_get_proc(struct thread *td, struct __mac_get_proc_args *uap)
{
char *elements, *buffer;
struct mac mac;
int error;
error = copyin(uap->mac_p, &mac, sizeof(mac));
if (error)
return (error);
error = mac_check_structmac_consistent(&mac);
if (error)
return (error);
elements = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK);
error = copyinstr(mac.m_string, elements, mac.m_buflen, NULL);
if (error) {
free(elements, M_MACTEMP);
return (error);
}
buffer = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK | M_ZERO);
error = mac_externalize_cred_label(&td->td_ucred->cr_label,
elements, buffer, mac.m_buflen, M_WAITOK);
if (error == 0)
error = copyout(buffer, mac.m_string, strlen(buffer)+1);
free(buffer, M_MACTEMP);
free(elements, M_MACTEMP);
return (error);
}
/*
* MPSAFE
*/
int
__mac_set_proc(struct thread *td, struct __mac_set_proc_args *uap)
{
struct ucred *newcred, *oldcred;
struct label intlabel;
struct proc *p;
struct mac mac;
char *buffer;
int error;
error = copyin(uap->mac_p, &mac, sizeof(mac));
if (error)
return (error);
error = mac_check_structmac_consistent(&mac);
if (error)
return (error);
buffer = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK);
error = copyinstr(mac.m_string, buffer, mac.m_buflen, NULL);
if (error) {
free(buffer, M_MACTEMP);
return (error);
}
mac_init_cred_label(&intlabel);
error = mac_internalize_cred_label(&intlabel, buffer);
free(buffer, M_MACTEMP);
if (error) {
mac_destroy_cred_label(&intlabel);
return (error);
}
newcred = crget();
p = td->td_proc;
PROC_LOCK(p);
oldcred = p->p_ucred;
error = mac_check_cred_relabel(oldcred, &intlabel);
if (error) {
PROC_UNLOCK(p);
crfree(newcred);
goto out;
}
setsugid(p);
crcopy(newcred, oldcred);
mac_relabel_cred(newcred, &intlabel);
p->p_ucred = newcred;
/*
* Grab additional reference for use while revoking mmaps, prior
* to releasing the proc lock and sharing the cred.
*/
crhold(newcred);
PROC_UNLOCK(p);
if (mac_enforce_vm) {
mtx_lock(&Giant);
mac_cred_mmapped_drop_perms(td, newcred);
mtx_unlock(&Giant);
}
crfree(newcred); /* Free revocation reference. */
crfree(oldcred);
out:
mac_destroy_cred_label(&intlabel);
return (error);
}
/*
* MPSAFE
*/
int
__mac_get_fd(struct thread *td, struct __mac_get_fd_args *uap)
{
char *elements, *buffer;
struct label intlabel;
struct file *fp;
struct mac mac;
struct vnode *vp;
struct pipe *pipe;
short label_type;
int error;
error = copyin(uap->mac_p, &mac, sizeof(mac));
if (error)
return (error);
error = mac_check_structmac_consistent(&mac);
if (error)
return (error);
elements = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK);
error = copyinstr(mac.m_string, elements, mac.m_buflen, NULL);
if (error) {
free(elements, M_MACTEMP);
return (error);
}
buffer = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK | M_ZERO);
mtx_lock(&Giant); /* VFS */
2002-12-14 01:56:26 +00:00
error = fget(td, uap->fd, &fp);
if (error)
goto out;
label_type = fp->f_type;
switch (fp->f_type) {
case DTYPE_FIFO:
case DTYPE_VNODE:
vp = fp->f_vnode;
mac_init_vnode_label(&intlabel);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
mac_copy_vnode_label(&vp->v_label, &intlabel);
VOP_UNLOCK(vp, 0, td);
break;
case DTYPE_PIPE:
pipe = fp->f_data;
mac_init_pipe_label(&intlabel);
PIPE_LOCK(pipe);
mac_copy_pipe_label(pipe->pipe_label, &intlabel);
PIPE_UNLOCK(pipe);
break;
default:
error = EINVAL;
fdrop(fp, td);
goto out;
}
fdrop(fp, td);
switch (label_type) {
case DTYPE_FIFO:
case DTYPE_VNODE:
if (error == 0)
error = mac_externalize_vnode_label(&intlabel,
elements, buffer, mac.m_buflen, M_WAITOK);
mac_destroy_vnode_label(&intlabel);
break;
case DTYPE_PIPE:
error = mac_externalize_pipe_label(&intlabel, elements,
buffer, mac.m_buflen, M_WAITOK);
mac_destroy_pipe_label(&intlabel);
break;
default:
panic("__mac_get_fd: corrupted label_type");
}
if (error == 0)
error = copyout(buffer, mac.m_string, strlen(buffer)+1);
out:
mtx_unlock(&Giant); /* VFS */
free(buffer, M_MACTEMP);
free(elements, M_MACTEMP);
return (error);
}
/*
* MPSAFE
*/
int
__mac_get_file(struct thread *td, struct __mac_get_file_args *uap)
{
char *elements, *buffer;
struct nameidata nd;
struct label intlabel;
struct mac mac;
int error;
error = copyin(uap->mac_p, &mac, sizeof(mac));
if (error)
return (error);
error = mac_check_structmac_consistent(&mac);
if (error)
return (error);
elements = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK);
error = copyinstr(mac.m_string, elements, mac.m_buflen, NULL);
if (error) {
free(elements, M_MACTEMP);
return (error);
}
buffer = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK | M_ZERO);
mtx_lock(&Giant); /* VFS */
NDINIT(&nd, LOOKUP, LOCKLEAF | FOLLOW, UIO_USERSPACE, uap->path_p,
td);
error = namei(&nd);
if (error)
goto out;
mac_init_vnode_label(&intlabel);
mac_copy_vnode_label(&nd.ni_vp->v_label, &intlabel);
error = mac_externalize_vnode_label(&intlabel, elements, buffer,
mac.m_buflen, M_WAITOK);
NDFREE(&nd, 0);
mac_destroy_vnode_label(&intlabel);
if (error == 0)
error = copyout(buffer, mac.m_string, strlen(buffer)+1);
out:
mtx_unlock(&Giant); /* VFS */
free(buffer, M_MACTEMP);
free(elements, M_MACTEMP);
return (error);
}
/*
* MPSAFE
*/
int
__mac_get_link(struct thread *td, struct __mac_get_link_args *uap)
{
char *elements, *buffer;
struct nameidata nd;
struct label intlabel;
struct mac mac;
int error;
error = copyin(uap->mac_p, &mac, sizeof(mac));
if (error)
return (error);
error = mac_check_structmac_consistent(&mac);
if (error)
return (error);
elements = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK);
error = copyinstr(mac.m_string, elements, mac.m_buflen, NULL);
if (error) {
free(elements, M_MACTEMP);
return (error);
}
buffer = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK | M_ZERO);
mtx_lock(&Giant); /* VFS */
NDINIT(&nd, LOOKUP, LOCKLEAF | NOFOLLOW, UIO_USERSPACE, uap->path_p,
td);
error = namei(&nd);
if (error)
goto out;
mac_init_vnode_label(&intlabel);
mac_copy_vnode_label(&nd.ni_vp->v_label, &intlabel);
error = mac_externalize_vnode_label(&intlabel, elements, buffer,
mac.m_buflen, M_WAITOK);
NDFREE(&nd, 0);
mac_destroy_vnode_label(&intlabel);
if (error == 0)
error = copyout(buffer, mac.m_string, strlen(buffer)+1);
out:
mtx_unlock(&Giant); /* VFS */
free(buffer, M_MACTEMP);
free(elements, M_MACTEMP);
return (error);
}
/*
* MPSAFE
*/
int
__mac_set_fd(struct thread *td, struct __mac_set_fd_args *uap)
{
struct label intlabel;
struct pipe *pipe;
struct file *fp;
struct mount *mp;
struct vnode *vp;
struct mac mac;
char *buffer;
int error;
error = copyin(uap->mac_p, &mac, sizeof(mac));
if (error)
return (error);
error = mac_check_structmac_consistent(&mac);
if (error)
return (error);
buffer = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK);
error = copyinstr(mac.m_string, buffer, mac.m_buflen, NULL);
if (error) {
free(buffer, M_MACTEMP);
return (error);
}
mtx_lock(&Giant); /* VFS */
2002-12-14 01:56:26 +00:00
error = fget(td, uap->fd, &fp);
if (error)
goto out;
switch (fp->f_type) {
case DTYPE_FIFO:
case DTYPE_VNODE:
mac_init_vnode_label(&intlabel);
error = mac_internalize_vnode_label(&intlabel, buffer);
if (error) {
mac_destroy_vnode_label(&intlabel);
break;
}
vp = fp->f_vnode;
error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
if (error != 0) {
mac_destroy_vnode_label(&intlabel);
break;
}
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
error = vn_setlabel(vp, &intlabel, td->td_ucred);
VOP_UNLOCK(vp, 0, td);
vn_finished_write(mp);
mac_destroy_vnode_label(&intlabel);
break;
case DTYPE_PIPE:
mac_init_pipe_label(&intlabel);
error = mac_internalize_pipe_label(&intlabel, buffer);
if (error == 0) {
pipe = fp->f_data;
PIPE_LOCK(pipe);
error = mac_pipe_label_set(td->td_ucred, pipe,
&intlabel);
PIPE_UNLOCK(pipe);
}
mac_destroy_pipe_label(&intlabel);
break;
default:
error = EINVAL;
}
fdrop(fp, td);
out:
mtx_unlock(&Giant); /* VFS */
free(buffer, M_MACTEMP);
return (error);
}
/*
* MPSAFE
*/
int
__mac_set_file(struct thread *td, struct __mac_set_file_args *uap)
{
struct label intlabel;
struct nameidata nd;
struct mount *mp;
struct mac mac;
char *buffer;
int error;
error = copyin(uap->mac_p, &mac, sizeof(mac));
if (error)
return (error);
error = mac_check_structmac_consistent(&mac);
if (error)
return (error);
buffer = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK);
error = copyinstr(mac.m_string, buffer, mac.m_buflen, NULL);
if (error) {
free(buffer, M_MACTEMP);
return (error);
}
mac_init_vnode_label(&intlabel);
error = mac_internalize_vnode_label(&intlabel, buffer);
free(buffer, M_MACTEMP);
if (error) {
mac_destroy_vnode_label(&intlabel);
return (error);
}
mtx_lock(&Giant); /* VFS */
NDINIT(&nd, LOOKUP, LOCKLEAF | FOLLOW, UIO_USERSPACE, uap->path_p,
td);
error = namei(&nd);
if (error == 0) {
error = vn_start_write(nd.ni_vp, &mp, V_WAIT | PCATCH);
if (error == 0)
error = vn_setlabel(nd.ni_vp, &intlabel,
td->td_ucred);
vn_finished_write(mp);
}
NDFREE(&nd, 0);
mtx_unlock(&Giant); /* VFS */
mac_destroy_vnode_label(&intlabel);
return (error);
}
/*
* MPSAFE
*/
int
__mac_set_link(struct thread *td, struct __mac_set_link_args *uap)
{
struct label intlabel;
struct nameidata nd;
struct mount *mp;
struct mac mac;
char *buffer;
int error;
error = copyin(uap->mac_p, &mac, sizeof(mac));
if (error)
return (error);
error = mac_check_structmac_consistent(&mac);
if (error)
return (error);
buffer = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK);
error = copyinstr(mac.m_string, buffer, mac.m_buflen, NULL);
if (error) {
free(buffer, M_MACTEMP);
return (error);
}
mac_init_vnode_label(&intlabel);
error = mac_internalize_vnode_label(&intlabel, buffer);
free(buffer, M_MACTEMP);
if (error) {
mac_destroy_vnode_label(&intlabel);
return (error);
}
mtx_lock(&Giant); /* VFS */
NDINIT(&nd, LOOKUP, LOCKLEAF | NOFOLLOW, UIO_USERSPACE, uap->path_p,
td);
error = namei(&nd);
if (error == 0) {
error = vn_start_write(nd.ni_vp, &mp, V_WAIT | PCATCH);
if (error == 0)
error = vn_setlabel(nd.ni_vp, &intlabel,
td->td_ucred);
vn_finished_write(mp);
}
NDFREE(&nd, 0);
mtx_unlock(&Giant); /* VFS */
mac_destroy_vnode_label(&intlabel);
return (error);
}
/*
* MPSAFE
*/
int
mac_syscall(struct thread *td, struct mac_syscall_args *uap)
{
struct mac_policy_conf *mpc;
char target[MAC_MAX_POLICY_NAME];
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
int entrycount, error;
2002-12-14 01:56:26 +00:00
error = copyinstr(uap->policy, target, sizeof(target), NULL);
if (error)
return (error);
error = ENOSYS;
LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) {
if (strcmp(mpc->mpc_name, target) == 0 &&
mpc->mpc_ops->mpo_syscall != NULL) {
error = mpc->mpc_ops->mpo_syscall(td,
2002-12-14 01:56:26 +00:00
uap->call, uap->arg);
goto out;
}
}
Clean up locking for the MAC Framework: (1) Accept that we're now going to use mutexes, so don't attempt to avoid treating them as mutexes. This cleans up locking accessor function names some. (2) Rename variables to _mtx, _cv, _count, simplifying the naming. (3) Add a new form of the _busy() primitive that conditionally makes the list busy: if there are entries on the list, bump the busy count. If there are no entries, don't bump the busy count. Return a boolean indicating whether or not the busy count was bumped. (4) Break mac_policy_list into two lists: one with the same name holding dynamic policies, and a new list, mac_static_policy_list, which holds policies loaded before mac_late and without the unload flag set. The static list may be accessed without holding the busy count, since it can't change at run-time. (5) In general, prefer making the list busy conditionally, meaning we pay only one mutex lock per entry point if all modules are on the static list, rather than two (since we don't have to lower the busy count when we're done with the framework). For systems running just Biba or MLS, this will halve the mutex accesses in the network stack, and may offer a substantial performance benefits. (6) Lay the groundwork for a dynamic-free kernel option which eliminates all locking associated with dynamically loaded or unloaded policies, for pre-configured systems requiring maximum performance but less run-time flexibility. These changes have been running for a few weeks on MAC development branch systems. Approved by: re (jhb) Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-05-07 17:49:24 +00:00
if ((entrycount = mac_policy_list_conditional_busy()) != 0) {
LIST_FOREACH(mpc, &mac_policy_list, mpc_list) {
if (strcmp(mpc->mpc_name, target) == 0 &&
mpc->mpc_ops->mpo_syscall != NULL) {
error = mpc->mpc_ops->mpo_syscall(td,
uap->call, uap->arg);
break;
}
}
mac_policy_list_unbusy();
}
out:
return (error);
}
SYSINIT(mac, SI_SUB_MAC, SI_ORDER_FIRST, mac_init, NULL);
SYSINIT(mac_late, SI_SUB_MAC_LATE, SI_ORDER_FIRST, mac_late_init, NULL);
#else /* !MAC */
int
__mac_get_pid(struct thread *td, struct __mac_get_pid_args *uap)
{
return (ENOSYS);
}
int
__mac_get_proc(struct thread *td, struct __mac_get_proc_args *uap)
{
return (ENOSYS);
}
int
__mac_set_proc(struct thread *td, struct __mac_set_proc_args *uap)
{
return (ENOSYS);
}
int
__mac_get_fd(struct thread *td, struct __mac_get_fd_args *uap)
{
return (ENOSYS);
}
int
__mac_get_file(struct thread *td, struct __mac_get_file_args *uap)
{
return (ENOSYS);
}
int
__mac_get_link(struct thread *td, struct __mac_get_link_args *uap)
{
return (ENOSYS);
}
int
__mac_set_fd(struct thread *td, struct __mac_set_fd_args *uap)
{
return (ENOSYS);
}
int
__mac_set_file(struct thread *td, struct __mac_set_file_args *uap)
{
return (ENOSYS);
}
int
__mac_set_link(struct thread *td, struct __mac_set_link_args *uap)
{
return (ENOSYS);
}
int
mac_syscall(struct thread *td, struct mac_syscall_args *uap)
{
return (ENOSYS);
}
#endif