[apple/xnu.git] / security / mac_policy.h

/*
 * Copyright (c) 2007-2016 Apple Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 *
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 *
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 *
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/*-
 * Copyright (c) 1999-2002 Robert N. M. Watson
 * Copyright (c) 2001-2005 Networks Associates Technology, Inc.
 * Copyright (c) 2005-2007 SPARTA, Inc.
 * All rights reserved.
 *
 * This software was developed by Robert Watson 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.
 *
 * This software was enhanced by SPARTA ISSO under SPAWAR contract
 * N66001-04-C-6019 ("SEFOS").
 *
 * 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.
 *
 * $FreeBSD: src/sys/sys/mac_policy.h,v 1.39 2003/04/18 19:57:37 rwatson Exp $
 */

/**
 *  @file mac_policy.h
 *  @brief Kernel Interfaces for MAC policy modules
 *
 *  This header defines the list of operations that are defined by the
 *  TrustedBSD MAC Framwork on Darwin.  MAC Policy modules register
 *  with the framework to declare interest in a specific set of
 *  operations.  If interest in an entry point is not declared, then
 *  the policy will be ignored when the Framework evaluates that entry
 *  point.
 */

#ifndef _SECURITY_MAC_POLICY_H_
#define _SECURITY_MAC_POLICY_H_

#ifndef PRIVATE
#warning "MAC policy is not KPI, see Technical Q&A QA1574, this header will be removed in next version"
#endif

#include <security/_label.h>

struct attrlist;
struct auditinfo;
struct bpf_d;
struct cs_blob;
struct devnode;
struct exception_action;
struct fileglob;
struct ifnet;
struct inpcb;
struct ipq;
struct label;
struct mac_module_data;
struct mac_policy_conf;
struct mbuf;
struct mount;
struct msg;
struct msqid_kernel;
struct pipe;
struct pseminfo;
struct pshminfo;
struct sbuf;
struct semid_kernel;
struct shmid_kernel;
struct socket;
struct sockopt;
struct task;
struct thread;
struct tty;
struct ucred;
struct vfs_attr;
struct vnode;
/** @struct dummy */



#ifndef _KAUTH_CRED_T
#define _KAUTH_CRED_T
typedef struct ucred *kauth_cred_t;
#endif  /* !_KAUTH_CRED_T */

#ifndef __IOKIT_PORTS_DEFINED__
#define __IOKIT_PORTS_DEFINED__
#ifdef __cplusplus
class OSObject;
typedef OSObject *io_object_t;
#else
struct OSObject;
typedef struct OSObject *io_object_t;
#endif
#endif /* __IOKIT_PORTS_DEFINED__ */

/*-
 * MAC entry points are generally named using the following template:
 *
 *   mpo_<object>_<operation>()
 *
 * or:
 *
 *   mpo_<object>_check_<operation>()
 *
 * Entry points are sorted by object type.
 *
 * It may be desirable also to consider some subsystems as "objects", such
 * as system, iokit, etc.
 */

/**
 *  @name Entry Points for Label Management
 *
 *  These are the entry points corresponding to the life cycle events for
 *  kernel objects, such as initialization, creation, and destruction.
 *
 *  Most policies (that use labels) will initialize labels by allocating
 *  space for policy-specific data.  In most cases, it is permitted to
 *  sleep during label initialization operations; it will be noted when
 *  it is not permitted.
 *
 *  Initialization usually will not require doing more than allocating a
 *  generic label for the given object.  What follows initialization is
 *  creation, where a label is made specific to the object it is associated
 *  with.  Destruction occurs when the label is no longer needed, such as
 *  when the corresponding object is destroyed.  All necessary cleanup should
 *  be performed in label destroy operations.
 *
 *  Where possible, the label entry points have identical parameters.  If
 *  the policy module does not require structure-specific label
 *  information, the same function may be registered in the policy
 *  operation vector.  Many policies will implement two such generic
 *  allocation calls: one to handle sleepable requests, and one to handle
 *  potentially non-sleepable requests.
 */


/**
 *  @brief Audit event postselection
 *  @param cred Subject credential
 *  @param syscode Syscall number
 *  @param args Syscall arguments
 *  @param error Syscall errno
 *  @param retval Syscall return value
 *
 *  This is the MAC Framework audit postselect, which is called before
 *  exiting a syscall to determine if an audit event should be committed.
 *  A return value of MAC_AUDIT_NO forces the audit record to be suppressed.
 *  Any other return value results in the audit record being committed.
 *
 *  @warning The suppression behavior will probably go away in Apple's
 *  future version of the audit implementation.
 *
 *  @return Return MAC_AUDIT_NO to force suppression of the audit record.
 *  Any other value results in the audit record being committed.
 *
 */
typedef int mpo_audit_check_postselect_t(
        kauth_cred_t cred,
        unsigned short syscode,
        void *args,
        int error,
        int retval
        );
/**
 *  @brief Audit event preselection
 *  @param cred Subject credential
 *  @param syscode Syscall number
 *  @param args Syscall arguments
 *
 *  This is the MAC Framework audit preselect, which is called before a
 *  syscall is entered to determine if an audit event should be created.
 *  If the MAC policy forces the syscall to be audited, MAC_AUDIT_YES should be
 *  returned. A return value of MAC_AUDIT_NO causes the audit record to
 *  be suppressed. Returning MAC_POLICY_DEFAULT indicates that the policy wants
 *  to defer to the system's existing preselection mechanism.
 *
 *  When policies return different preferences, the Framework decides what action
 *  to take based on the following policy.  If any policy returns MAC_AUDIT_YES,
 *  then create an audit record, else if any policy returns MAC_AUDIT_NO, then
 *  suppress the creations of an audit record, else defer to the system's
 *  existing preselection mechanism.
 *
 *  @warning The audit implementation in Apple's current version is
 *  incomplete, so the MAC policies have priority over the system's existing
 *  mechanisms. This will probably change in the future version where
 *  the audit implementation is more complete.
 *
 *  @return Return MAC_AUDIT_YES to force auditing of the syscall,
 *  MAC_AUDIT_NO to force no auditing of the syscall, MAC_AUDIT_DEFAULT
 *  to allow auditing mechanisms to determine if the syscall is audited.
 *
 */
typedef int mpo_audit_check_preselect_t(
        kauth_cred_t cred,
        unsigned short syscode,
        void *args
        );
/**
 *  @brief Initialize BPF descriptor label
 *  @param label New label to initialize
 *
 *  Initialize the label for a newly instantiated BPF descriptor.
 *  Sleeping is permitted.
 */
typedef void mpo_bpfdesc_label_init_t(
        struct label *label
        );
/**
 *  @brief Destroy BPF descriptor label
 *  @param label The label to be destroyed
 *
 *  Destroy a BPF descriptor label.  Since the BPF descriptor
 *  is going out of scope, policy modules should free any internal
 *  storage associated with the label so that it may be destroyed.
 */
typedef void mpo_bpfdesc_label_destroy_t(
        struct label *label
        );
/**
 *  @brief Associate a BPF descriptor with a label
 *  @param cred User credential creating the BPF descriptor
 *  @param bpf_d The BPF descriptor
 *  @param bpflabel The new label
 *
 *  Set the label on a newly created BPF descriptor from the passed
 *  subject credential. This call will be made when a BPF device node
 *  is opened by a process with the passed subject credential.
 */
typedef void mpo_bpfdesc_label_associate_t(
        kauth_cred_t cred,
        struct bpf_d *bpf_d,
        struct label *bpflabel
        );
/**
 *  @brief Check whether BPF can read from a network interface
 *  @param bpf_d Subject; the BPF descriptor
 *  @param bpflabel Policy label for bpf_d
 *  @param ifp Object; the network interface
 *  @param ifnetlabel Policy label for ifp
 *
 *  Determine whether the MAC framework should permit datagrams from
 *  the passed network interface to be delivered to the buffers of
 *  the passed BPF descriptor.  Return (0) for success, or an errno
 *  value for failure.  Suggested failure: EACCES for label mismatches,
 *  EPERM for lack of privilege.
 */
typedef int mpo_bpfdesc_check_receive_t(
        struct bpf_d *bpf_d,
        struct label *bpflabel,
        struct ifnet *ifp,
        struct label *ifnetlabel
        );
/**
 *  @brief Indicate desire to change the process label at exec time
 *  @param old Existing subject credential
 *  @param vp File being executed
 *  @param offset Offset of binary within file being executed
 *  @param scriptvp Script being executed by interpreter, if any.
 *  @param vnodelabel Label corresponding to vp
 *  @param scriptvnodelabel Script vnode label
 *  @param execlabel Userspace provided execution label
 *  @param p Object process
 *  @param macpolicyattr MAC policy-specific spawn attribute data
 *  @param macpolicyattrlen Length of policy-specific spawn attribute data
 *  @see mac_execve
 *  @see mpo_cred_label_update_execve_t
 *  @see mpo_vnode_check_exec_t
 *
 *  Indicate whether this policy intends to update the label of a newly
 *  created credential from the existing subject credential (old).  This
 *  call occurs when a process executes the passed vnode.  If a policy
 *  returns success from this entry point, the mpo_cred_label_update_execve
 *  entry point will later be called with the same parameters.  Access
 *  has already been checked via the mpo_vnode_check_exec entry point,
 *  this entry point is necessary to preserve kernel locking constraints
 *  during program execution.
 *
 *  The supplied vnode and vnodelabel correspond with the file actually
 *  being executed; in the case that the file is interpreted (for
 *  example, a script), the label of the original exec-time vnode has
 *  been preserved in scriptvnodelabel.
 *
 *  The final label, execlabel, corresponds to a label supplied by a
 *  user space application through the use of the mac_execve system call.
 *
 *  The vnode lock is held during this operation.  No changes should be
 *  made to the old credential structure.
 *
 *  @warning Even if a policy returns 0, it should behave correctly in
 *  the presence of an invocation of mpo_cred_label_update_execve, as that
 *  call may happen as a result of another policy requesting a transition.
 *
 *  @return Non-zero if a transition is required, 0 otherwise.
 */
typedef int mpo_cred_check_label_update_execve_t(
        kauth_cred_t old,
        struct vnode *vp,
        off_t offset,
        struct vnode *scriptvp,
        struct label *vnodelabel,
        struct label *scriptvnodelabel,
        struct label *execlabel,
        struct proc *p,
        void *macpolicyattr,
        size_t macpolicyattrlen
        );
/**
 *  @brief Access control check for relabelling processes
 *  @param cred Subject credential
 *  @param newlabel New label to apply to the user credential
 *  @see mpo_cred_label_update_t
 *  @see mac_set_proc
 *
 *  Determine whether the subject identified by the credential can relabel
 *  itself to the supplied new label (newlabel).  This access control check
 *  is called when the mac_set_proc system call is invoked.  A user space
 *  application will supply a new value, the value will be internalized
 *  and provided in newlabel.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_cred_check_label_update_t(
        kauth_cred_t cred,
        struct label *newlabel
        );
/**
 *  @brief Access control check for visibility of other subjects
 *  @param u1 Subject credential
 *  @param u2 Object credential
 *
 *  Determine whether the subject identified by the credential u1 can
 *  "see" other subjects with the passed subject credential u2. This call
 *  may be made in a number of situations, including inter-process status
 *  sysctls used by ps, and in procfs lookups.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch,
 *  EPERM for lack of privilege, or ESRCH to hide visibility.
 */
typedef int mpo_cred_check_visible_t(
        kauth_cred_t u1,
        kauth_cred_t u2
        );
/**
 *  @brief Associate a credential with a new process at fork
 *  @param cred credential to inherited by new process
 *  @param proc the new process
 *
 *  Allow a process to associate the credential with a new
 *  process for reference countng purposes.
 *  NOTE: the credential can be dis-associated in ways other
 *       than exit - so this strategy is flawed - should just
 *       catch label destroy callback.
 */
typedef void mpo_cred_label_associate_fork_t(
        kauth_cred_t cred,
        proc_t proc
        );
/**
 *  @brief Create the first process
 *  @param cred Subject credential to be labeled
 *
 *  Create the subject credential of process 0, the parent of all BSD
 *  kernel processes.  Policies should update the label in the
 *  previously initialized credential structure.
 */
typedef void mpo_cred_label_associate_kernel_t(
        kauth_cred_t cred
        );
/**
 *  @brief Create a credential label
 *  @param parent_cred Parent credential
 *  @param child_cred Child credential
 *
 *  Set the label of a newly created credential, most likely using the
 *  information in the supplied parent credential.
 *
 *  @warning This call is made when crcopy or crdup is invoked on a
 *  newly created struct ucred, and should not be confused with a
 *  process fork or creation event.
 */
typedef void mpo_cred_label_associate_t(
        kauth_cred_t parent_cred,
        kauth_cred_t child_cred
        );
/**
 *  @brief Create the first process
 *  @param cred Subject credential to be labeled
 *
 *  Create the subject credential of process 1, the parent of all BSD
 *  user processes.  Policies should update the label in the previously
 *  initialized credential structure.  This is the 'init' process.
 */
typedef void mpo_cred_label_associate_user_t(
        kauth_cred_t cred
        );
/**
 *  @brief Destroy credential label
 *  @param label The label to be destroyed
 *
 *  Destroy a user credential label.  Since the user credential
 *  is going out of scope, policy modules should free any internal
 *  storage associated with the label so that it may be destroyed.
 */
typedef void mpo_cred_label_destroy_t(
        struct label *label
        );
/**
 *  @brief Externalize a user credential label for auditing
 *  @param label Label to be externalized
 *  @param element_name Name of the label namespace for which labels should be
 *  externalized
 *  @param sb String buffer to be filled with a text representation of the label
 *
 *  Produce an external representation of the label on a user credential for
 *  inclusion in an audit record.  An externalized label consists of a text
 *  representation of the label contents that will be added to the audit record
 *  as part of a text token.  Policy-agnostic user space tools will display
 *  this externalized version.
 *
 *  @return 0 on success, return non-zero if an error occurs while
 *  externalizing the label data.
 *
 */
typedef int mpo_cred_label_externalize_audit_t(
        struct label *label,
        char *element_name,
        struct sbuf *sb
        );
/**
 *  @brief Externalize a user credential label
 *  @param label Label to be externalized
 *  @param element_name Name of the label namespace for which labels should be
 *  externalized
 *  @param sb String buffer to be filled with a text representation of the label
 *
 *  Produce an external representation of the label on a user
 *  credential.  An externalized label consists of a text representation
 *  of the label contents that can be used with user applications.
 *  Policy-agnostic user space tools will display this externalized
 *  version.
 *
 *  @return 0 on success, return non-zero if an error occurs while
 *  externalizing the label data.
 *
 */
typedef int mpo_cred_label_externalize_t(
        struct label *label,
        char *element_name,
        struct sbuf *sb
        );
/**
 *  @brief Initialize user credential label
 *  @param label New label to initialize
 *
 *  Initialize the label for a newly instantiated user credential.
 *  Sleeping is permitted.
 */
typedef void mpo_cred_label_init_t(
        struct label *label
        );
/**
 *  @brief Internalize a user credential label
 *  @param label Label to be internalized
 *  @param element_name Name of the label namespace for which the label should
 *  be internalized
 *  @param element_data Text data to be internalized
 *
 *  Produce a user credential label from an external representation.  An
 *  externalized label consists of a text representation of the label
 *  contents that can be used with user applications.  Policy-agnostic
 *  user space tools will forward text version to the kernel for
 *  processing by individual policy modules.
 *
 *  The policy's internalize entry points will be called only if the
 *  policy has registered interest in the label namespace.
 *
 *  @return 0 on success, Otherwise, return non-zero if an error occurs
 *  while internalizing the label data.
 *
 */
typedef int mpo_cred_label_internalize_t(
        struct label *label,
        char *element_name,
        char *element_data
        );
/**
 *  @brief Update credential at exec time
 *  @param old_cred Existing subject credential
 *  @param new_cred New subject credential to be labeled
 *  @param p Object process.
 *  @param vp File being executed
 *  @param offset Offset of binary within file being executed
 *  @param scriptvp Script being executed by interpreter, if any.
 *  @param vnodelabel Label corresponding to vp
 *  @param scriptvnodelabel Script vnode label
 *  @param execlabel Userspace provided execution label
 *  @param csflags Code signing flags to be set after exec
 *  @param macpolicyattr MAC policy-specific spawn attribute data.
 *  @param macpolicyattrlen Length of policy-specific spawn attribute data.
 *  @see mac_execve
 *  @see mpo_cred_check_label_update_execve_t
 *  @see mpo_vnode_check_exec_t
 *
 *  Update the label of a newly created credential (new) from the
 *  existing subject credential (old).  This call occurs when a process
 *  executes the passed vnode and one of the loaded policy modules has
 *  returned success from the mpo_cred_check_label_update_execve entry point.
 *  Access has already been checked via the mpo_vnode_check_exec entry
 *  point, this entry point is only used to update any policy state.
 *
 *  The supplied vnode and vnodelabel correspond with the file actually
 *  being executed; in the case that the file is interpreted (for
 *  example, a script), the label of the original exec-time vnode has
 *  been preserved in scriptvnodelabel.
 *
 *  The final label, execlabel, corresponds to a label supplied by a
 *  user space application through the use of the mac_execve system call.
 *
 *  If non-NULL, the value pointed to by disjointp will be set to 0 to
 *  indicate that the old and new credentials are not disjoint, or 1 to
 *  indicate that they are.
 *
 *  The vnode lock is held during this operation.  No changes should be
 *  made to the old credential structure.
 *  @return 0 on success, Otherwise, return non-zero if update results in
 *  termination of child.
 */
typedef int mpo_cred_label_update_execve_t(
        kauth_cred_t old_cred,
        kauth_cred_t new_cred,
        struct proc *p,
        struct vnode *vp,
        off_t offset,
        struct vnode *scriptvp,
        struct label *vnodelabel,
        struct label *scriptvnodelabel,
        struct label *execlabel,
        u_int *csflags,
        void *macpolicyattr,
        size_t macpolicyattrlen,
        int *disjointp
        );
/**
 *  @brief Update a credential label
 *  @param cred The existing credential
 *  @param newlabel A new label to apply to the credential
 *  @see mpo_cred_check_label_update_t
 *  @see mac_set_proc
 *
 *  Update the label on a user credential, using the supplied new label.
 *  This is called as a result of a process relabel operation.  Access
 *  control was already confirmed by mpo_cred_check_label_update.
 */
typedef void mpo_cred_label_update_t(
        kauth_cred_t cred,
        struct label *newlabel
        );
/**
 *  @brief Create a new devfs device
 *  @param dev Major and minor numbers of special file
 *  @param de "inode" of new device file
 *  @param label Destination label
 *  @param fullpath Path relative to mount (e.g. /dev) of new device file
 *
 *  This entry point labels a new devfs device. The label will likely be based
 *  on the path to the device, or the major and minor numbers.
 *  The policy should store an appropriate label into 'label'.
 */
typedef void mpo_devfs_label_associate_device_t(
        dev_t dev,
        struct devnode *de,
        struct label *label,
        const char *fullpath
        );
/**
 *  @brief Create a new devfs directory
 *  @param dirname Name of new directory
 *  @param dirnamelen Length of 'dirname'
 *  @param de "inode" of new directory
 *  @param label Destination label
 *  @param fullpath Path relative to mount (e.g. /dev) of new directory
 *
 *  This entry point labels a new devfs directory. The label will likely be
 *  based on the path of the new directory. The policy should store an appropriate
 *  label into 'label'. The devfs root directory is labelled in this way.
 */
typedef void mpo_devfs_label_associate_directory_t(
        const char *dirname,
        int dirnamelen,
        struct devnode *de,
        struct label *label,
        const char *fullpath
        );
/**
 *  @brief Copy a devfs label
 *  @param src Source devfs label
 *  @param dest Destination devfs label
 *
 *  Copy the label information from src to dest.  The devfs file system
 *  often duplicates (splits) existing device nodes rather than creating
 *  new ones.
 */
typedef void mpo_devfs_label_copy_t(
        struct label *src,
        struct label *dest
        );
/**
 *  @brief Destroy devfs label
 *  @param label The label to be destroyed
 *
 *  Destroy a devfs entry label.  Since the object is going out
 *  of scope, policy modules should free any internal storage associated
 *  with the label so that it may be destroyed.
 */
typedef void mpo_devfs_label_destroy_t(
        struct label *label
        );
/**
 *  @brief Initialize devfs label
 *  @param label New label to initialize
 *
 *  Initialize the label for a newly instantiated devfs entry.  Sleeping
 *  is permitted.
 */
typedef void mpo_devfs_label_init_t(
        struct label *label
        );
/**
 *  @brief Update a devfs label after relabelling its vnode
 *  @param mp Devfs mount point
 *  @param de Affected devfs directory entry
 *  @param delabel Label of devfs directory entry
 *  @param vp Vnode associated with de
 *  @param vnodelabel New label of vnode
 *
 *  Update a devfs label when its vnode is manually relabelled,
 *  for example with setfmac(1). Typically, this will simply copy
 *  the vnode label into the devfs label.
 */
typedef void mpo_devfs_label_update_t(
        struct mount *mp,
        struct devnode *de,
        struct label *delabel,
        struct vnode *vp,
        struct label *vnodelabel
        );
/**
 *  @brief Access control for sending an exception to an exception action
 *  @param crashlabel The crashing process's label
 *  @param action Exception action
 *  @param exclabel Policy label for exception action
 *
 *  Determine whether the the exception message caused by the victim
 *  process can be sent to the exception action. The policy may compare
 *  credentials in the crashlabel, which are derived from the process at
 *  the time the exception occurs, with the credentials in the exclabel,
 *  which was set at the time the exception port was set, to determine
 *  its decision. Note that any process from which the policy derived
 *  any credentials may not exist anymore at the time of this policy
 *  operation. Sleeping is permitted.
 *
 *  @return Return 0 if the message can be sent, otherwise an
 *  appropriate value for errno should be returned.
 */
typedef int mpo_exc_action_check_exception_send_t(
        struct label *crashlabel,
        struct exception_action *action,
        struct label *exclabel
        );
/**
 *  @brief Associate an exception action label
 *  @param action Exception action to label
 *  @param exclabel Policy label to be filled in for exception action
 *
 *  Set the label on an exception action.
 */
typedef void mpo_exc_action_label_associate_t(
        struct exception_action *action,
        struct label *exclabel
        );
/**
 *  @brief Destroy exception action label
 *  @param label The label to be destroyed
 *
 *  Destroy the label on an exception action. Since the object is going
 *  out of scope, policy modules should free any internal storage
 *  associated with the label so that it may be destroyed. Sleeping is
 *  permitted.
 */
typedef void mpo_exc_action_label_destroy_t(
        struct label *label
        );
/**
 *  @brief Populate an exception action label with process credentials
 *  @param label The label to be populated
 *  @param proc Process to derive credentials from
 *
 *  Populate a label with credentials derived from a process. At
 *  exception delivery time, the policy should compare credentials of the
 *  process that set an exception ports with the credentials of the
 *  process or corpse that experienced the exception. Note that the
 *  process that set the port may not exist at that time anymore, so
 *  labels should carry copies of live credentials if necessary.
 */
typedef void mpo_exc_action_label_populate_t(
        struct label *label,
        struct proc *proc
        );
/**
 *  @brief Initialize exception action label
 *  @param label New label to initialize
 *
 *  Initialize a label for an exception action. Usually performs
 *  policy specific allocations. Sleeping is permitted.
 */
typedef int mpo_exc_action_label_init_t(
        struct label *label
        );
/**
 *  @brief Update the label on an exception action
 *  @param action Exception action that the label belongs to (may be
 *               NULL if none)
 *  @param label Policy label to update
 *  @param newlabel New label for update
 *
 *  Update the credentials of an exception action from the given
 *  label. The policy should copy over any credentials (process and
 *  otherwise) from the new label into the label to update. Must not
 *  sleep, must be quick and can be called with locks held.
 */
typedef int mpo_exc_action_label_update_t(
        struct exception_action *action,
        struct label *label,
        struct label *newlabel
        );
/**
 *  @brief Access control for changing the offset of a file descriptor
 *  @param cred Subject credential
 *  @param fg Fileglob structure
 *  @param label Policy label for fg
 *
 *  Determine whether the subject identified by the credential can
 *  change the offset of the file represented by fg.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_file_check_change_offset_t(
        kauth_cred_t cred,
        struct fileglob *fg,
        struct label *label
        );
/**
 *  @brief Access control for creating a file descriptor
 *  @param cred Subject credential
 *
 *  Determine whether the subject identified by the credential can
 *  allocate a new file descriptor.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_file_check_create_t(
        kauth_cred_t cred
        );
/**
 *  @brief Access control for duplicating a file descriptor
 *  @param cred Subject credential
 *  @param fg Fileglob structure
 *  @param label Policy label for fg
 *  @param newfd New file descriptor number
 *
 *  Determine whether the subject identified by the credential can
 *  duplicate the fileglob structure represented by fg and as file
 *  descriptor number newfd.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_file_check_dup_t(
        kauth_cred_t cred,
        struct fileglob *fg,
        struct label *label,
        int newfd
        );
/**
 *  @brief Access control check for fcntl
 *  @param cred Subject credential
 *  @param fg Fileglob structure
 *  @param label Policy label for fg
 *  @param cmd Control operation to be performed; see fcntl(2)
 *  @param arg fcnt arguments; see fcntl(2)
 *
 *  Determine whether the subject identified by the credential can perform
 *  the file control operation indicated by cmd.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_file_check_fcntl_t(
        kauth_cred_t cred,
        struct fileglob *fg,
        struct label *label,
        int cmd,
        user_long_t arg
        );
/**
 *  @brief Access control check for mac_get_fd
 *  @param cred Subject credential
 *  @param fg Fileglob structure
 *  @param elements Element buffer
 *  @param len Length of buffer
 *
 *  Determine whether the subject identified by the credential should be allowed
 *  to get an externalized version of the label on the object indicated by fd.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_file_check_get_t(
        kauth_cred_t cred,
        struct fileglob *fg,
        char *elements,
        int len
        );
/**
 *  @brief Access control for getting the offset of a file descriptor
 *  @param cred Subject credential
 *  @param fg Fileglob structure
 *  @param label Policy label for fg
 *
 *  Determine whether the subject identified by the credential can
 *  get the offset of the file represented by fg.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_file_check_get_offset_t(
        kauth_cred_t cred,
        struct fileglob *fg,
        struct label *label
        );
/**
 *  @brief Access control for inheriting a file descriptor
 *  @param cred Subject credential
 *  @param fg Fileglob structure
 *  @param label Policy label for fg
 *
 *  Determine whether the subject identified by the credential can
 *  inherit the fileglob structure represented by fg.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_file_check_inherit_t(
        kauth_cred_t cred,
        struct fileglob *fg,
        struct label *label
        );
/**
 *  @brief Access control check for file ioctl
 *  @param cred Subject credential
 *  @param fg Fileglob structure
 *  @param label Policy label for fg
 *  @param cmd The ioctl command; see ioctl(2)
 *
 *  Determine whether the subject identified by the credential can perform
 *  the ioctl operation indicated by cmd.
 *
 *  @warning Since ioctl data is opaque from the standpoint of the MAC
 *  framework, policies must exercise extreme care when implementing
 *  access control checks.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 *
 */
typedef int mpo_file_check_ioctl_t(
        kauth_cred_t cred,
        struct fileglob *fg,
        struct label *label,
        unsigned int cmd
        );
/**
 *  @brief Access control check for file locking
 *  @param cred Subject credential
 *  @param fg Fileglob structure
 *  @param label Policy label for fg
 *  @param op The lock operation (F_GETLK, F_SETLK, F_UNLK)
 *  @param fl The flock structure
 *
 *  Determine whether the subject identified by the credential can perform
 *  the lock operation indicated by op and fl on the file represented by fg.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 *
 */
typedef int mpo_file_check_lock_t(
        kauth_cred_t cred,
        struct fileglob *fg,
        struct label *label,
        int op,
        struct flock *fl
        );
/**
 *  @brief Check with library validation if a macho slice is allowed to be combined into a proc.
 *  @param p Subject process
 *  @param fg Fileglob structure
 *  @param slice_offset offset of the code slice
 *  @param error_message error message returned to user-space in case of error (userspace pointer)
 *  @param error_message_size error message size
 *
 *  Its a little odd that the MAC/kext writes into userspace since this
 *  implies there is only one MAC module that implements this, however
 *  the alterantive is to allocate memory in xnu, on the hope that
 *  the MAC module will use it, or allocated in the MAC module and then
 *  free it in xnu. Either of these are very appeling, so lets go with
 *  the slightly more hacky way.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_file_check_library_validation_t(
        struct proc *p,
        struct fileglob *fg,
        off_t slice_offset,
        user_long_t error_message,
        size_t error_message_size
        );
/**
 *  @brief Access control check for mapping a file
 *  @param cred Subject credential
 *  @param fg fileglob representing file to map
 *  @param label Policy label associated with vp
 *  @param prot mmap protections; see mmap(2)
 *  @param flags Type of mapped object; see mmap(2)
 *  @param maxprot Maximum rights
 *
 *  Determine whether the subject identified by the credential should be
 *  allowed to map the file represented by fg with the protections specified
 *  in prot.  The maxprot field holds the maximum permissions on the new
 *  mapping, a combination of VM_PROT_READ, VM_PROT_WRITE, and VM_PROT_EXECUTE.
 *  To avoid overriding prior access control checks, a policy should only
 *  remove flags from maxprot.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_file_check_mmap_t(
        kauth_cred_t cred,
        struct fileglob *fg,
        struct label *label,
        int prot,
        int flags,
        uint64_t file_pos,
        int *maxprot
        );
/**
 *  @brief Downgrade the mmap protections
 *  @param cred Subject credential
 *  @param fg file to map
 *  @param label Policy label associated with vp
 *  @param prot mmap protections to be downgraded
 *
 *  Downgrade the mmap protections based on the subject and object labels.
 */
typedef void mpo_file_check_mmap_downgrade_t(
        kauth_cred_t cred,
        struct fileglob *fg,
        struct label *label,
        int *prot
        );
/**
 *  @brief Access control for receiving a file descriptor
 *  @param cred Subject credential
 *  @param fg Fileglob structure
 *  @param label Policy label for fg
 *
 *  Determine whether the subject identified by the credential can
 *  receive the fileglob structure represented by fg.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_file_check_receive_t(
        kauth_cred_t cred,
        struct fileglob *fg,
        struct label *label
        );
/**
 *  @brief Access control check for mac_set_fd
 *  @param cred Subject credential
 *  @param fg Fileglob structure
 *  @param elements Elements buffer
 *  @param len Length of elements buffer
 *
 *  Determine whether the subject identified by the credential can
 *  perform the mac_set_fd operation.  The mac_set_fd operation is used
 *  to associate a MAC label with a file.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_file_check_set_t(
        kauth_cred_t cred,
        struct fileglob *fg,
        char *elements,
        int len
        );
/**
 *  @brief Create file label
 *  @param cred Subject credential
 *  @param fg Fileglob structure
 *  @param label Policy label for fg
 */
typedef void mpo_file_label_associate_t(
        kauth_cred_t cred,
        struct fileglob *fg,
        struct label *label
        );
/**
 *  @brief Destroy file label
 *  @param label The label to be destroyed
 *
 *  Destroy the label on a file descriptor.  In this entry point, a
 *  policy module should free any internal storage associated with
 *  label so that it may be destroyed.
 */
typedef void mpo_file_label_destroy_t(
        struct label *label
        );
/**
 *  @brief Initialize file label
 *  @param label New label to initialize
 */
typedef void mpo_file_label_init_t(
        struct label *label
        );
/**
 *  @brief Access control check for relabeling network interfaces
 *  @param cred Subject credential
 *  @param ifp network interface being relabeled
 *  @param ifnetlabel Current label of the network interfaces
 *  @param newlabel New label to apply to the network interfaces
 *  @see mpo_ifnet_label_update_t
 *
 *  Determine whether the subject identified by the credential can
 *  relabel the network interface represented by ifp to the supplied
 *  new label (newlabel).
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_ifnet_check_label_update_t(
        kauth_cred_t cred,
        struct ifnet *ifp,
        struct label *ifnetlabel,
        struct label *newlabel
        );
/**
 *  @brief Access control check for relabeling network interfaces
 *  @param ifp Network interface mbuf will be transmitted through
 *  @param ifnetlabel Label of the network interfaces
 *  @param m The mbuf to be transmitted
 *  @param mbuflabel Label of the mbuf to be transmitted
 *  @param family Address Family, AF_*
 *  @param type Type of socket, SOCK_{STREAM,DGRAM,RAW}
 *
 *  Determine whether the mbuf with label mbuflabel may be transmitted
 *  through the network interface represented by ifp that has the
 *  label ifnetlabel.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_ifnet_check_transmit_t(
        struct ifnet *ifp,
        struct label *ifnetlabel,
        struct mbuf *m,
        struct label *mbuflabel,
        int family,
        int type
        );
/**
 *  @brief Create a network interface label
 *  @param ifp Network interface labeled
 *  @param ifnetlabel Label for the network interface
 *
 *  Set the label of a newly created network interface, most likely
 *  using the information in the supplied network interface struct.
 */
typedef void mpo_ifnet_label_associate_t(
        struct ifnet *ifp,
        struct label *ifnetlabel
        );
/**
 *  @brief Copy an ifnet label
 *  @param src Source ifnet label
 *  @param dest Destination ifnet label
 *
 *  Copy the label information from src to dest.
 */
typedef void mpo_ifnet_label_copy_t(
        struct label *src,
        struct label *dest
        );
/**
 *  @brief Destroy ifnet label
 *  @param label The label to be destroyed
 *
 *  Destroy the label on an ifnet label.  In this entry point, a
 *  policy module should free any internal storage associated with
 *  label so that it may be destroyed.
 */
typedef void mpo_ifnet_label_destroy_t(
        struct label *label
        );
/**
 *  @brief Externalize an ifnet label
 *  @param label Label to be externalized
 *  @param element_name Name of the label namespace for which labels should be
 *  externalized
 *  @param sb String buffer to be filled with a text representation of the label
 *
 *  Produce an external representation of the label on an interface.
 *  An externalized label consists of a text representation of the
 *  label contents that can be used with user applications.
 *  Policy-agnostic user space tools will display this externalized
 *  version.
 *
 *  @return 0 on success, return non-zero if an error occurs while
 *  externalizing the label data.
 *
 */
typedef int mpo_ifnet_label_externalize_t(
        struct label *label,
        char *element_name,
        struct sbuf *sb
        );
/**
 *  @brief Initialize ifnet label
 *  @param label New label to initialize
 */
typedef void mpo_ifnet_label_init_t(
        struct label *label
        );
/**
 *  @brief Internalize an interface label
 *  @param label Label to be internalized
 *  @param element_name Name of the label namespace for which the label should
 *  be internalized
 *  @param element_data Text data to be internalized
 *
 *  Produce an interface label from an external representation.  An
 *  externalized label consists of a text representation of the label
 *  contents that can be used with user applications.  Policy-agnostic
 *  user space tools will forward text version to the kernel for
 *  processing by individual policy modules.
 *
 *  The policy's internalize entry points will be called only if the
 *  policy has registered interest in the label namespace.
 *
 *  @return 0 on success, Otherwise, return non-zero if an error occurs
 *  while internalizing the label data.
 *
 */
typedef int mpo_ifnet_label_internalize_t(
        struct label *label,
        char *element_name,
        char *element_data
        );
/**
 *  @brief Recycle up a network interface label
 *  @param label The label to be recycled
 *
 *  Recycle a network interface label.  Darwin caches the struct ifnet
 *  of detached ifnets in a "free pool".  Before ifnets are returned
 *  to the "free pool", policies can cleanup or overwrite any information
 *  present in the label.
 */
typedef void mpo_ifnet_label_recycle_t(
        struct label *label
        );
/**
 *  @brief Update a network interface label
 *  @param cred Subject credential
 *  @param ifp The network interface to be relabeled
 *  @param ifnetlabel The current label of the network interface
 *  @param newlabel A new label to apply to the network interface
 *  @see mpo_ifnet_check_label_update_t
 *
 *  Update the label on a network interface, using the supplied new label.
 */
typedef void mpo_ifnet_label_update_t(
        kauth_cred_t cred,
        struct ifnet *ifp,
        struct label *ifnetlabel,
        struct label *newlabel
        );
/**
 *  @brief Access control check for delivering a packet to a socket
 *  @param inp inpcb the socket is associated with
 *  @param inplabel Label of the inpcb
 *  @param m The mbuf being received
 *  @param mbuflabel Label of the mbuf being received
 *  @param family Address family, AF_*
 *  @param type Type of socket, SOCK_{STREAM,DGRAM,RAW}
 *
 *  Determine whether the mbuf with label mbuflabel may be received
 *  by the socket associated with inpcb that has the label inplabel.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_inpcb_check_deliver_t(
        struct inpcb *inp,
        struct label *inplabel,
        struct mbuf *m,
        struct label *mbuflabel,
        int family,
        int type
        );
/**
 *  @brief Create an inpcb label
 *  @param so Socket containing the inpcb to be labeled
 *  @param solabel Label of the socket
 *  @param inp inpcb to be labeled
 *  @param inplabel Label for the inpcb
 *
 *  Set the label of a newly created inpcb, most likely
 *  using the information in the socket and/or socket label.
 */
typedef void mpo_inpcb_label_associate_t(
        struct socket *so,
        struct label *solabel,
        struct inpcb *inp,
        struct label *inplabel
        );
/**
 *  @brief Destroy inpcb label
 *  @param label The label to be destroyed
 *
 *  Destroy the label on an inpcb label.  In this entry point, a
 *  policy module should free any internal storage associated with
 *  label so that it may be destroyed.
 */
typedef void mpo_inpcb_label_destroy_t(
        struct label *label
        );
/**
 *  @brief Initialize inpcb label
 *  @param label New label to initialize
 *  @param flag M_WAITOK or M_NOWAIT
 */
typedef int mpo_inpcb_label_init_t(
        struct label *label,
        int flag
        );
/**
 *  @brief Recycle up an inpcb label
 *  @param label The label to be recycled
 *
 *  Recycle an inpcb label.  Darwin allocates the inpcb as part of
 *  the socket structure in some cases.  For this case we must recycle
 *  rather than destroy the inpcb as it will be reused later.
 */
typedef void mpo_inpcb_label_recycle_t(
        struct label *label
        );
/**
 *  @brief Update an inpcb label from a socket label
 *  @param so Socket containing the inpcb to be relabeled
 *  @param solabel New label of the socket
 *  @param inp inpcb to be labeled
 *  @param inplabel Label for the inpcb
 *
 *  Set the label of a newly created inpcb due to a change in the
 *  underlying socket label.
 */
typedef void mpo_inpcb_label_update_t(
        struct socket *so,
        struct label *solabel,
        struct inpcb *inp,
        struct label *inplabel
        );
/**
 *  @brief Device hardware access control
 *  @param devtype Type of device connected
 *
 *  This is the MAC Framework device access control, which is called by the I/O
 *  Kit when a new device is connected to the system to determine whether that
 *  device should be trusted.  A list of properties associated with the device
 *  is passed as an XML-formatted string.  The routine should examine these
 *  properties to determine the trustworthiness of the device.  A return value
 *  of EPERM forces the device to be claimed by a special device driver that
 *  will prevent its operation.
 *
 *  @warning This is an experimental interface and may change in the future.
 *
 *  @return Return EPERM to indicate that the device is untrusted and should
 *  not be allowed to operate.  Return zero to indicate that the device is
 *  trusted and should be allowed to operate normally.
 *
 */
typedef int mpo_iokit_check_device_t(
        char *devtype,
        struct mac_module_data *mdata
        );
/**
 *  @brief Access control check for opening an I/O Kit device
 *  @param cred Subject credential
 *  @param user_client User client instance
 *  @param user_client_type User client type
 *
 *  Determine whether the subject identified by the credential can open an
 *  I/O Kit device at the passed path of the passed user client class and
 *  type.
 *
 *  @return Return 0 if access is granted, or an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_iokit_check_open_t(
        kauth_cred_t cred,
        io_object_t user_client,
        unsigned int user_client_type
        );
/**
 *  @brief Access control check for setting I/O Kit device properties
 *  @param cred Subject credential
 *  @param entry Target device
 *  @param properties Property list
 *
 *  Determine whether the subject identified by the credential can set
 *  properties on an I/O Kit device.
 *
 *  @return Return 0 if access is granted, or an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_iokit_check_set_properties_t(
        kauth_cred_t cred,
        io_object_t entry,
        io_object_t properties
        );
/**
 *  @brief Indicate desire to filter I/O Kit devices properties
 *  @param cred Subject credential
 *  @param entry Target device
 *  @see mpo_iokit_check_get_property_t
 *
 *  Indicate whether this policy may restrict the subject credential
 *  from reading properties of the target device.
 *  If a policy returns success from this entry point, the
 *  mpo_iokit_check_get_property entry point will later be called
 *  for each property that the subject credential tries to read from
 *  the target device.
 *
 *  This entry point is primarilly to optimize bulk property reads
 *  by skipping calls to the mpo_iokit_check_get_property entry point
 *  for credentials / devices no MAC policy is interested in.
 *
 *  @warning Even if a policy returns 0, it should behave correctly in
 *  the presence of an invocation of mpo_iokit_check_get_property, as that
 *  call may happen as a result of another policy requesting a transition.
 *
 *  @return Non-zero if a transition is required, 0 otherwise.
 */
typedef int mpo_iokit_check_filter_properties_t(
        kauth_cred_t cred,
        io_object_t entry
        );
/**
 *  @brief Access control check for getting I/O Kit device properties
 *  @param cred Subject credential
 *  @param entry Target device
 *  @param name Property name
 *
 *  Determine whether the subject identified by the credential can get
 *  properties on an I/O Kit device.
 *
 *  @return Return 0 if access is granted, or an appropriate value for
 *  errno.
 */
typedef int mpo_iokit_check_get_property_t(
        kauth_cred_t cred,
        io_object_t entry,
        const char *name
        );
/**
 *  @brief Access control check for software HID control
 *  @param cred Subject credential
 *
 *  Determine whether the subject identified by the credential can
 *  control the HID (Human Interface Device) subsystem, such as to
 *  post synthetic keypresses, pointer movement and clicks.
 *
 *  @return Return 0 if access is granted, or an appropriate value for
 *  errno.
 */
typedef int mpo_iokit_check_hid_control_t(
        kauth_cred_t cred
        );
/**
 *  @brief Create an IP reassembly queue label
 *  @param fragment First received IP fragment
 *  @param fragmentlabel Policy label for fragment
 *  @param ipq IP reassembly queue to be labeled
 *  @param ipqlabel Policy label to be filled in for ipq
 *
 *  Set the label on a newly created IP reassembly queue from
 *  the mbuf header of the first received fragment.
 */
typedef void mpo_ipq_label_associate_t(
        struct mbuf *fragment,
        struct label *fragmentlabel,
        struct ipq *ipq,
        struct label *ipqlabel
        );
/**
 *  @brief Compare an mbuf header label to an ipq label
 *  @param fragment IP datagram fragment
 *  @param fragmentlabel Policy label for fragment
 *  @param ipq IP fragment reassembly queue
 *  @param ipqlabel Policy label for ipq
 *
 *  Compare the label of the mbuf header containing an IP datagram
 *  (fragment) fragment with the label of the passed IP fragment
 *  reassembly queue (ipq). Return (1) for a successful match, or (0)
 *  for no match. This call is made when the IP stack attempts to
 *  find an existing fragment reassembly queue for a newly received
 *  fragment; if this fails, a new fragment reassembly queue may be
 *  instantiated for the fragment. Policies may use this entry point
 *  to prevent the reassembly of otherwise matching IP fragments if
 *  policy does not permit them to be reassembled based on the label
 *  or other information.
 */
typedef int mpo_ipq_label_compare_t(
        struct mbuf *fragment,
        struct label *fragmentlabel,
        struct ipq *ipq,
        struct label *ipqlabel
        );
/**
 *  @brief Destroy IP reassembly queue label
 *  @param label The label to be destroyed
 *
 *  Destroy the label on an IP fragment queue.  In this entry point, a
 *  policy module should free any internal storage associated with
 *  label so that it may be destroyed.
 */
typedef void mpo_ipq_label_destroy_t(
        struct label *label
        );
/**
 *  @brief Initialize IP reassembly queue label
 *  @param label New label to initialize
 *  @param flag M_WAITOK or M_NOWAIT
 *
 *  Initialize the label on a newly instantiated IP fragment reassembly
 *  queue.  The flag field may be one of M_WAITOK and M_NOWAIT, and
 *  should be employed to avoid performing a sleeping malloc(9) during
 *  this initialization call. IP fragment reassembly queue allocation
 *  frequently occurs in performance sensitive environments, and the
 *  implementation should be careful to avoid sleeping or long-lived
 *  operations. This entry point is permitted to fail resulting in
 *  the failure to allocate the IP fragment reassembly queue.
 */
typedef int mpo_ipq_label_init_t(
        struct label *label,
        int flag
        );
/**
 *  @brief Update the label on an IP fragment reassembly queue
 *  @param fragment IP fragment
 *  @param fragmentlabel Policy label for fragment
 *  @param ipq IP fragment reassembly queue
 *  @param ipqlabel Policy label to be updated for ipq
 *
 *  Update the label on an IP fragment reassembly queue (ipq) based
 *  on the acceptance of the passed IP fragment mbuf header (fragment).
 */
typedef void mpo_ipq_label_update_t(
        struct mbuf *fragment,
        struct label *fragmentlabel,
        struct ipq *ipq,
        struct label *ipqlabel
        );
/**
 *  @brief Assign a label to a new mbuf
 *  @param bpf_d BPF descriptor
 *  @param b_label Policy label for bpf_d
 *  @param m Object; mbuf
 *  @param m_label Policy label to fill in for m
 *
 *  Set the label on the mbuf header of a newly created datagram
 *  generated using the passed BPF descriptor. This call is made when
 *  a write is performed to the BPF device associated with the passed
 *  BPF descriptor.
 */
typedef void mpo_mbuf_label_associate_bpfdesc_t(
        struct bpf_d *bpf_d,
        struct label *b_label,
        struct mbuf *m,
        struct label *m_label
        );
/**
 *  @brief Assign a label to a new mbuf
 *  @param ifp Interface descriptor
 *  @param i_label Existing label of ifp
 *  @param m Object; mbuf
 *  @param m_label Policy label to fill in for m
 *
 *  Label an mbuf based on the interface from which it was received.
 */
typedef void mpo_mbuf_label_associate_ifnet_t(
        struct ifnet *ifp,
        struct label *i_label,
        struct mbuf *m,
        struct label *m_label
        );
/**
 *  @brief Assign a label to a new mbuf
 *  @param inp inpcb structure
 *  @param i_label Existing label of inp
 *  @param m Object; mbuf
 *  @param m_label Policy label to fill in for m
 *
 *  Label an mbuf based on the inpcb from which it was derived.
 */
typedef void mpo_mbuf_label_associate_inpcb_t(
        struct inpcb *inp,
        struct label *i_label,
        struct mbuf *m,
        struct label *m_label
        );
/**
 *  @brief Set the label on a newly reassembled IP datagram
 *  @param ipq IP fragment reassembly queue
 *  @param ipqlabel Policy label for ipq
 *  @param mbuf IP datagram to be labeled
 *  @param mbuflabel Policy label to be filled in for mbuf
 *
 *  Set the label on a newly reassembled IP datagram (mbuf) from the IP
 *  fragment reassembly queue (ipq) from which it was generated.
 */
typedef void mpo_mbuf_label_associate_ipq_t(
        struct ipq *ipq,
        struct label *ipqlabel,
        struct mbuf *mbuf,
        struct label *mbuflabel
        );
/**
 *  @brief Assign a label to a new mbuf
 *  @param ifp Subject; network interface
 *  @param i_label Existing label of ifp
 *  @param m Object; mbuf
 *  @param m_label Policy label to fill in for m
 *
 *  Set the label on the mbuf header of a newly created datagram
 *  generated for the purposes of a link layer response for the passed
 *  interface. This call may be made in a number of situations, including
 *  for ARP or ND6 responses in the IPv4 and IPv6 stacks.
 */
typedef void mpo_mbuf_label_associate_linklayer_t(
        struct ifnet *ifp,
        struct label *i_label,
        struct mbuf *m,
        struct label *m_label
        );
/**
 *  @brief Assign a label to a new mbuf
 *  @param oldmbuf mbuf headerder for existing datagram for existing datagram
 *  @param oldmbuflabel Policy label for oldmbuf
 *  @param ifp Network interface
 *  @param ifplabel Policy label for ifp
 *  @param newmbuf mbuf header to be labeled for new datagram
 *  @param newmbuflabel Policy label for newmbuf
 *
 *  Set the label on the mbuf header of a newly created datagram
 *  generated from the existing passed datagram when it is processed
 *  by the passed multicast encapsulation interface. This call is made
 *  when an mbuf is to be delivered using the virtual interface.
 */
typedef void mpo_mbuf_label_associate_multicast_encap_t(
        struct mbuf *oldmbuf,
        struct label *oldmbuflabel,
        struct ifnet *ifp,
        struct label *ifplabel,
        struct mbuf *newmbuf,
        struct label *newmbuflabel
        );
/**
 *  @brief Assign a label to a new mbuf
 *  @param oldmbuf Received datagram
 *  @param oldmbuflabel Policy label for oldmbuf
 *  @param newmbuf Newly created datagram
 *  @param newmbuflabel Policy label for newmbuf
 *
 *  Set the label on the mbuf header of a newly created datagram generated
 *  by the IP stack in response to an existing received datagram (oldmbuf).
 *  This call may be made in a number of situations, including when responding
 *  to ICMP request datagrams.
 */
typedef void mpo_mbuf_label_associate_netlayer_t(
        struct mbuf *oldmbuf,
        struct label *oldmbuflabel,
        struct mbuf *newmbuf,
        struct label *newmbuflabel
        );
/**
 *  @brief Assign a label to a new mbuf
 *  @param so Socket to label
 *  @param so_label Policy label for socket
 *  @param m Object; mbuf
 *  @param m_label Policy label to fill in for m
 *
 *  An mbuf structure is used to store network traffic in transit.
 *  When an application sends data to a socket or a pipe, it is wrapped
 *  in an mbuf first.  This function sets the label on a newly created mbuf header
 *  based on the socket sending the data.  The contents of the label should be
 *  suitable for performing an access check on the receiving side of the
 *  communication.
 *
 *  Only labeled MBUFs will be presented to the policy via this entrypoint.
 */
typedef void mpo_mbuf_label_associate_socket_t(
        socket_t so,
        struct label *so_label,
        struct mbuf *m,
        struct label *m_label
        );
/**
 *  @brief Copy a mbuf label
 *  @param src Source label
 *  @param dest Destination label
 *
 *  Copy the mbuf label information in src into dest.
 *
 *  Only called when both source and destination mbufs have labels.
 */
typedef void mpo_mbuf_label_copy_t(
        struct label *src,
        struct label *dest
        );
/**
 *  @brief Destroy mbuf label
 *  @param label The label to be destroyed
 *
 *  Destroy a mbuf label.  Since the
 *  object is going out of scope, policy modules should free any
 *  internal storage associated with the label so that it may be
 *  destroyed.
 */
typedef void mpo_mbuf_label_destroy_t(
        struct label *label
        );
/**
 *  @brief Initialize mbuf label
 *  @param label New label to initialize
 *  @param flag Malloc flags
 *
 *  Initialize the label for a newly instantiated mbuf.
 *
 *  @warning Since it is possible for the flags to be set to
 *  M_NOWAIT, the malloc operation may fail.
 *
 *  @return On success, 0, otherwise, an appropriate errno return value.
 */
typedef int mpo_mbuf_label_init_t(
        struct label *label,
        int flag
        );
/**
 *  @brief Access control check for fsctl
 *  @param cred Subject credential
 *  @param mp The mount point
 *  @param label Label associated with the mount point
 *  @param cmd Filesystem-dependent request code; see fsctl(2)
 *
 *  Determine whether the subject identified by the credential can perform
 *  the volume operation indicated by com.
 *
 *  @warning The fsctl() system call is directly analogous to ioctl(); since
 *  the associated data is opaque from the standpoint of the MAC framework
 *  and since these operations can affect many aspects of system operation,
 *  policies must exercise extreme care when implementing access control checks.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_mount_check_fsctl_t(
        kauth_cred_t cred,
        struct mount *mp,
        struct label *label,
        unsigned int cmd
        );
/**
 *  @brief Access control check for the retrieval of file system attributes
 *  @param cred Subject credential
 *  @param mp The mount structure of the file system
 *  @param vfa The attributes requested
 *
 *  This entry point determines whether given subject can get information
 *  about the given file system.  This check happens during statfs() syscalls,
 *  but is also used by other parts within the kernel such as the audit system.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 *
 *  @note Policies may change the contents of vfa to alter the list of
 *  file system attributes returned.
 */

typedef int mpo_mount_check_getattr_t(
        kauth_cred_t cred,
        struct mount *mp,
        struct label *mp_label,
        struct vfs_attr *vfa
        );
/**
 *  @brief Access control check for mount point relabeling
 *  @param cred Subject credential
 *  @param mp Object file system mount point
 *  @param mntlabel Policy label for fle system mount point
 *
 *  Determine whether the subject identified by the credential can relabel
 *  the mount point. This call is made when a file system mount is updated.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch
 *  or EPERM for lack of privilege.
 */
typedef int mpo_mount_check_label_update_t(
        kauth_cred_t cred,
        struct mount *mp,
        struct label *mntlabel
        );
/**
 *  @brief Access control check for mounting a file system
 *  @param cred Subject credential
 *  @param vp Vnode that is to be the mount point
 *  @param vlabel Label associated with the vnode
 *  @param cnp Component name for vp
 *  @param vfc_name Filesystem type name
 *
 *  Determine whether the subject identified by the credential can perform
 *  the mount operation on the target vnode.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_mount_check_mount_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *vlabel,
        struct componentname *cnp,
        const char *vfc_name
        );
/**
 *  @brief Access control check for fs_snapshot_create
 *  @param cred Subject credential
 *  @mp Filesystem mount point to create snapshot of
 *  @name Name of snapshot to create
 *
 *  Determine whether the subject identified by the credential can
 *  create a snapshot of the filesystem at the given mount point.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value
 *  for errno should be returned.
 */
typedef int mpo_mount_check_snapshot_create_t(
        kauth_cred_t cred,
        struct mount *mp,
        const char *name
        );
/**
 *  @brief Access control check for fs_snapshot_delete
 *  @param cred Subject credential
 *  @mp Filesystem mount point to delete snapshot of
 *  @name Name of snapshot to delete
 *
 *  Determine whether the subject identified by the credential can
 *  delete the named snapshot from the filesystem at the given
 *  mount point.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value
 *  for errno should be returned.
 */
typedef int mpo_mount_check_snapshot_delete_t(
        kauth_cred_t cred,
        struct mount *mp,
        const char *name
        );
/**
 *  @brief Access control check for fs_snapshot_revert
 *  @param cred Subject credential
 *  @mp Filesystem mount point to revert to snapshot
 *  @name Name of snapshot to revert to
 *
 *  Determine whether the subject identified by the credential can
 *  revert the filesystem at the given mount point to the named snapshot.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value
 *  for errno should be returned.
 */
typedef int mpo_mount_check_snapshot_revert_t(
        kauth_cred_t cred,
        struct mount *mp,
        const char *name
        );
/**
 *  @brief Access control check remounting a filesystem
 *  @param cred Subject credential
 *  @param mp The mount point
 *  @param mlabel Label currently associated with the mount point
 *
 *  Determine whether the subject identified by the credential can perform
 *  the remount operation on the target vnode.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_mount_check_remount_t(
        kauth_cred_t cred,
        struct mount *mp,
        struct label *mlabel
        );
/**
 *  @brief Access control check for the settting of file system attributes
 *  @param cred Subject credential
 *  @param mp The mount structure of the file system
 *  @param vfa The attributes requested
 *
 *  This entry point determines whether given subject can set information
 *  about the given file system, for example the volume name.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */

typedef int mpo_mount_check_setattr_t(
        kauth_cred_t cred,
        struct mount *mp,
        struct label *mp_label,
        struct vfs_attr *vfa
        );
/**
 *  @brief Access control check for file system statistics
 *  @param cred Subject credential
 *  @param mp Object file system mount
 *  @param mntlabel Policy label for mp
 *
 *  Determine whether the subject identified by the credential can see
 *  the results of a statfs performed on the file system. This call may
 *  be made in a number of situations, including during invocations of
 *  statfs(2) and related calls, as well as to determine what file systems
 *  to exclude from listings of file systems, such as when getfsstat(2)
 *  is invoked.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch
 *  or EPERM for lack of privilege.
 */
typedef int mpo_mount_check_stat_t(
        kauth_cred_t cred,
        struct mount *mp,
        struct label *mntlabel
        );
/**
 *  @brief Access control check for unmounting a filesystem
 *  @param cred Subject credential
 *  @param mp The mount point
 *  @param mlabel Label associated with the mount point
 *
 *  Determine whether the subject identified by the credential can perform
 *  the unmount operation on the target vnode.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_mount_check_umount_t(
        kauth_cred_t cred,
        struct mount *mp,
        struct label *mlabel
        );
/**
 *  @brief Create mount labels
 *  @param cred Subject credential
 *  @param mp Mount point of file system being mounted
 *  @param mntlabel Label to associate with the new mount point
 *  @see mpo_mount_label_init_t
 *
 *  Fill out the labels on the mount point being created by the supplied
 *  user credential.  This call is made when file systems are first mounted.
 */
typedef void mpo_mount_label_associate_t(
        kauth_cred_t cred,
        struct mount *mp,
        struct label *mntlabel
        );
/**
 *  @brief Destroy mount label
 *  @param label The label to be destroyed
 *
 *  Destroy a file system mount label.  Since the
 *  object is going out of scope, policy modules should free any
 *  internal storage associated with the label so that it may be
 *  destroyed.
 */
typedef void mpo_mount_label_destroy_t(
        struct label *label
        );
/**
 *  @brief Externalize a mount point label
 *  @param label Label to be externalized
 *  @param element_name Name of the label namespace for which labels should be
 *  externalized
 *  @param sb String buffer to be filled with a text representation of the label
 *
 *  Produce an external representation of the mount point label.  An
 *  externalized label consists of a text representation of the label
 *  contents that can be used with user applications.  Policy-agnostic
 *  user space tools will display this externalized version.
 *
 *  The policy's externalize entry points will be called only if the
 *  policy has registered interest in the label namespace.
 *
 *  @return 0 on success, return non-zero if an error occurs while
 *  externalizing the label data.
 *
 */
typedef int mpo_mount_label_externalize_t(
        struct label *label,
        char *element_name,
        struct sbuf *sb
        );
/**
 *  @brief Initialize mount point label
 *  @param label New label to initialize
 *
 *  Initialize the label for a newly instantiated mount structure.
 *  This label is typically used to store a default label in the case
 *  that the file system has been mounted singlelabel.  Since some
 *  file systems do not support persistent labels (extended attributes)
 *  or are read-only (such as CD-ROMs), it is often necessary to store
 *  a default label separately from the label of the mount point
 *  itself.  Sleeping is permitted.
 */
typedef void mpo_mount_label_init_t(
        struct label *label
        );
/**
 *  @brief Internalize a mount point label
 *  @param label Label to be internalized
 *  @param element_name Name of the label namespace for which the label should
 *  be internalized
 *  @param element_data Text data to be internalized
 *
 *  Produce a mount point file system label from an external representation.
 *  An externalized label consists of a text representation of the label
 *  contents that can be used with user applications.  Policy-agnostic
 *  user space tools will forward text version to the kernel for
 *  processing by individual policy modules.
 *
 *  The policy's internalize entry points will be called only if the
 *  policy has registered interest in the label namespace.
 *
 *  @return 0 on success, Otherwise, return non-zero if an error occurs
 *  while internalizing the label data.
 *
 */
typedef int mpo_mount_label_internalize_t(
        struct label *label,
        char *element_name,
        char *element_data
        );
/**
 *  @brief Set the label on an IPv4 datagram fragment
 *  @param datagram Datagram being fragmented
 *  @param datagramlabel Policy label for datagram
 *  @param fragment New fragment
 *  @param fragmentlabel Policy label for fragment
 *
 *  Called when an IPv4 datagram is fragmented into several smaller datagrams.
 *  Policies implementing mbuf labels will typically copy the label from the
 *  source datagram to the new fragment.
 */
typedef void mpo_netinet_fragment_t(
        struct mbuf *datagram,
        struct label *datagramlabel,
        struct mbuf *fragment,
        struct label *fragmentlabel
        );
/**
 *  @brief Set the label on an ICMP reply
 *  @param m mbuf containing the ICMP reply
 *  @param mlabel Policy label for m
 *
 *  A policy may wish to update the label of an mbuf that refers to
 *  an ICMP packet being sent in response to an IP packet.  This may
 *  be called in response to a bad packet or an ICMP request.
 */
typedef void mpo_netinet_icmp_reply_t(
        struct mbuf *m,
        struct label *mlabel
        );
/**
 *  @brief Set the label on a TCP reply
 *  @param m mbuf containing the TCP reply
 *  @param mlabel Policy label for m
 *
 *  Called for outgoing TCP packets not associated with an actual socket.
 */
typedef void mpo_netinet_tcp_reply_t(
        struct mbuf *m,
        struct label *mlabel
        );
/**
 *  @brief Access control check for pipe ioctl
 *  @param cred Subject credential
 *  @param cpipe Object to be accessed
 *  @param pipelabel The label on the pipe
 *  @param cmd The ioctl command; see ioctl(2)
 *
 *  Determine whether the subject identified by the credential can perform
 *  the ioctl operation indicated by cmd.
 *
 *  @warning Since ioctl data is opaque from the standpoint of the MAC
 *  framework, policies must exercise extreme care when implementing
 *  access control checks.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 *
 */
typedef int mpo_pipe_check_ioctl_t(
        kauth_cred_t cred,
        struct pipe *cpipe,
        struct label *pipelabel,
        unsigned int cmd
        );
/**
 *  @brief Access control check for pipe kqfilter
 *  @param cred Subject credential
 *  @param kn Object knote
 *  @param cpipe Object to be accessed
 *  @param pipelabel Policy label for the pipe
 *
 *  Determine whether the subject identified by the credential can
 *  receive the knote on the passed pipe.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_pipe_check_kqfilter_t(
        kauth_cred_t cred,
        struct knote *kn,
        struct pipe *cpipe,
        struct label *pipelabel
        );
/**
 *  @brief Access control check for pipe relabel
 *  @param cred Subject credential
 *  @param cpipe Object to be accessed
 *  @param pipelabel The current label on the pipe
 *  @param newlabel The new label to be used
 *
 *  Determine whether the subject identified by the credential can
 *  perform a relabel operation on the passed pipe.  The cred object holds
 *  the credentials of the subject performing the operation.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 *
 */
typedef int mpo_pipe_check_label_update_t(
        kauth_cred_t cred,
        struct pipe *cpipe,
        struct label *pipelabel,
        struct label *newlabel
        );
/**
 *  @brief Access control check for pipe read
 *  @param cred Subject credential
 *  @param cpipe Object to be accessed
 *  @param pipelabel The label on the pipe
 *
 *  Determine whether the subject identified by the credential can
 *  perform a read operation on the passed pipe.  The cred object holds
 *  the credentials of the subject performing the operation.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 *
 */
typedef int mpo_pipe_check_read_t(
        kauth_cred_t cred,
        struct pipe *cpipe,
        struct label *pipelabel
        );
/**
 *  @brief Access control check for pipe select
 *  @param cred Subject credential
 *  @param cpipe Object to be accessed
 *  @param pipelabel The label on the pipe
 *  @param which The operation selected on: FREAD or FWRITE
 *
 *  Determine whether the subject identified by the credential can
 *  perform a select operation on the passed pipe.  The cred object holds
 *  the credentials of the subject performing the operation.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 *
 */
typedef int mpo_pipe_check_select_t(
        kauth_cred_t cred,
        struct pipe *cpipe,
        struct label *pipelabel,
        int which
        );
/**
 *  @brief Access control check for pipe stat
 *  @param cred Subject credential
 *  @param cpipe Object to be accessed
 *  @param pipelabel The label on the pipe
 *
 *  Determine whether the subject identified by the credential can
 *  perform a stat operation on the passed pipe.  The cred object holds
 *  the credentials of the subject performing the operation.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 *
 */
typedef int mpo_pipe_check_stat_t(
        kauth_cred_t cred,
        struct pipe *cpipe,
        struct label *pipelabel
        );
/**
 *  @brief Access control check for pipe write
 *  @param cred Subject credential
 *  @param cpipe Object to be accessed
 *  @param pipelabel The label on the pipe
 *
 *  Determine whether the subject identified by the credential can
 *  perform a write operation on the passed pipe.  The cred object holds
 *  the credentials of the subject performing the operation.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 *
 */
typedef int mpo_pipe_check_write_t(
        kauth_cred_t cred,
        struct pipe *cpipe,
        struct label *pipelabel
        );
/**
 *  @brief Create a pipe label
 *  @param cred Subject credential
 *  @param cpipe object to be labeled
 *  @param pipelabel Label for the pipe object
 *
 *  Create a label for the pipe object being created by the supplied
 *  user credential. This call is made when the pipe is being created
 *  XXXPIPE(for one or both sides of the pipe?).
 *
 */
typedef void mpo_pipe_label_associate_t(
        kauth_cred_t cred,
        struct pipe *cpipe,
        struct label *pipelabel
        );
/**
 *  @brief Copy a pipe label
 *  @param src Source pipe label
 *  @param dest Destination pipe label
 *
 *  Copy the pipe label associated with src to dest.
 *  XXXPIPE Describe when this is used: most likely during pipe creation to
 *         copy from rpipe to wpipe.
 */
typedef void mpo_pipe_label_copy_t(
        struct label *src,
        struct label *dest
        );
/**
 *  @brief Destroy pipe label
 *  @param label The label to be destroyed
 *
 *  Destroy a pipe label.  Since the object is going out of scope,
 *  policy modules should free any internal storage associated with the
 *  label so that it may be destroyed.
 */
typedef void mpo_pipe_label_destroy_t(
        struct label *label
        );
/**
 *  @brief Externalize a pipe label
 *  @param label Label to be externalized
 *  @param element_name Name of the label namespace for which labels should be
 *  externalized
 *  @param sb String buffer to be filled with a text representation of the label
 *
 *  Produce an external representation of the label on a pipe.
 *  An externalized label consists of a text representation
 *  of the label contents that can be used with user applications.
 *  Policy-agnostic user space tools will display this externalized
 *  version.
 *
 *  The policy's externalize entry points will be called only if the
 *  policy has registered interest in the label namespace.
 *
 *  @return 0 on success, return non-zero if an error occurs while
 *  externalizing the label data.
 *
 */
typedef int mpo_pipe_label_externalize_t(
        struct label *label,
        char *element_name,
        struct sbuf *sb
        );
/**
 *  @brief Initialize pipe label
 *  @param label New label to initialize
 *
 *  Initialize label storage for use with a newly instantiated pipe object.
 *  Sleeping is permitted.
 */
typedef void mpo_pipe_label_init_t(
        struct label *label
        );
/**
 *  @brief Internalize a pipe label
 *  @param label Label to be internalized
 *  @param element_name Name of the label namespace for which the label should
 *  be internalized
 *  @param element_data Text data to be internalized
 *
 *  Produce a pipe label from an external representation.  An
 *  externalized label consists of a text representation of the label
 *  contents that can be used with user applications.  Policy-agnostic
 *  user space tools will forward text version to the kernel for
 *  processing by individual policy modules.
 *
 *  The policy's internalize entry points will be called only if the
 *  policy has registered interest in the label namespace.
 *
 *  @return 0 on success, Otherwise, return non-zero if an error occurs
 *  while internalizing the label data.
 *
 */
typedef int mpo_pipe_label_internalize_t(
        struct label *label,
        char *element_name,
        char *element_data
        );
/**
 *  @brief Update a pipe label
 *  @param cred Subject credential
 *  @param cpipe Object to be labeled
 *  @param oldlabel Existing pipe label
 *  @param newlabel New label to replace existing label
 *  @see mpo_pipe_check_label_update_t
 *
 *  The subject identified by the credential has previously requested
 *  and was authorized to relabel the pipe; this entry point allows
 *  policies to perform the actual relabel operation.  Policies should
 *  update oldlabel using the label stored in the newlabel parameter.
 *
 */
typedef void mpo_pipe_label_update_t(
        kauth_cred_t cred,
        struct pipe *cpipe,
        struct label *oldlabel,
        struct label *newlabel
        );
/**
 *  @brief Policy unload event
 *  @param mpc MAC policy configuration
 *
 *  This is the MAC Framework policy unload event.  This entry point will
 *  only be called if the module's policy configuration allows unload (if
 *  the MPC_LOADTIME_FLAG_UNLOADOK is set).  Most security policies won't
 *  want to be unloaded; they should set their flags to prevent this
 *  entry point from being called.
 *
 *  @warning During this call, the mac policy list mutex is held, so
 *  sleep operations cannot be performed, and calls out to other kernel
 *  subsystems must be made with caution.
 *
 *  @see MPC_LOADTIME_FLAG_UNLOADOK
 */
typedef void mpo_policy_destroy_t(
        struct mac_policy_conf *mpc
        );
/**
 *  @brief Policy initialization event
 *  @param mpc MAC policy configuration
 *  @see mac_policy_register
 *  @see mpo_policy_initbsd_t
 *
 *  This is the MAC Framework policy initialization event.  This entry
 *  point is called during mac_policy_register, when the policy module
 *  is first registered with the MAC Framework.  This is often done very
 *  early in the boot process, after the kernel Mach subsystem has been
 *  initialized, but prior to the BSD subsystem being initialized.
 *  Since the kernel BSD services are not yet available, it is possible
 *  that some initialization must occur later, possibly in the
 *  mpo_policy_initbsd_t policy entry point, such as registering BSD system
 *  controls (sysctls).  Policy modules loaded at boot time will be
 *  registered and initialized before labeled Mach objects are created.
 *
 *  @warning During this call, the mac policy list mutex is held, so
 *  sleep operations cannot be performed, and calls out to other kernel
 *  subsystems must be made with caution.
 */
typedef void mpo_policy_init_t(
        struct mac_policy_conf *mpc
        );
/**
 *  @brief Policy BSD initialization event
 *  @param mpc MAC policy configuration
 *  @see mpo_policy_init_t
 *
 *  This entry point is called after the kernel BSD subsystem has been
 *  initialized.  By this point, the module should already be loaded,
 *  registered, and initialized.  Since policy modules are initialized
 *  before kernel BSD services are available, this second initialization
 *  phase is necessary.  At this point, BSD services (memory management,
 *  synchronization primitives, vfs, etc.) are available, but the first
 *  process has not yet been created.  Mach-related objects and tasks
 *  will already be fully initialized and may be in use--policies requiring
 *  ubiquitous labeling may also want to implement mpo_policy_init_t.
 *
 *  @warning During this call, the mac policy list mutex is held, so
 *  sleep operations cannot be performed, and calls out to other kernel
 *  subsystems must be made with caution.
 */
typedef void mpo_policy_initbsd_t(
        struct mac_policy_conf *mpc
        );
/**
 *  @brief Policy extension service
 *  @param p Calling process
 *  @param call Policy-specific syscall number
 *  @param arg Pointer to syscall arguments
 *
 *  This entry point provides a policy-multiplexed system call so that
 *  policies may provide additional services to user processes without
 *  registering specific system calls. The policy name provided during
 *  registration is used to demux calls from userland, and the arguments
 *  will be forwarded to this entry point.  When implementing new
 *  services, security modules should be sure to invoke appropriate
 *  access control checks from the MAC framework as needed.  For
 *  example, if a policy implements an augmented signal functionality,
 *  it should call the necessary signal access control checks to invoke
 *  the MAC framework and other registered policies.
 *
 *  @warning Since the format and contents of the policy-specific
 *  arguments are unknown to the MAC Framework, modules must perform the
 *  required copyin() of the syscall data on their own.  No policy
 *  mediation is performed, so policies must perform any necessary
 *  access control checks themselves.  If multiple policies are loaded,
 *  they will currently be unable to mediate calls to other policies.
 *
 *  @return In the event of an error, an appropriate value for errno
 *  should be returned, otherwise return 0 upon success.
 */
typedef int mpo_policy_syscall_t(
        struct proc *p,
        int call,
        user_addr_t arg
        );
/**
 *  @brief Access control check for POSIX semaphore create
 *  @param cred Subject credential
 *  @param name String name of the semaphore
 *
 *  Determine whether the subject identified by the credential can create
 *  a POSIX semaphore specified by name.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_posixsem_check_create_t(
        kauth_cred_t cred,
        const char *name
        );
/**
 *  @brief Access control check for POSIX semaphore open
 *  @param cred Subject credential
 *  @param ps Pointer to semaphore information structure
 *  @param semlabel Label associated with the semaphore
 *
 *  Determine whether the subject identified by the credential can open
 *  the named POSIX semaphore with label semlabel.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_posixsem_check_open_t(
        kauth_cred_t cred,
        struct pseminfo *ps,
        struct label *semlabel
        );
/**
 *  @brief Access control check for POSIX semaphore post
 *  @param cred Subject credential
 *  @param ps Pointer to semaphore information structure
 *  @param semlabel Label associated with the semaphore
 *
 *  Determine whether the subject identified by the credential can unlock
 *  the named POSIX semaphore with label semlabel.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_posixsem_check_post_t(
        kauth_cred_t cred,
        struct pseminfo *ps,
        struct label *semlabel
        );
/**
 *  @brief Access control check for POSIX semaphore unlink
 *  @param cred Subject credential
 *  @param ps Pointer to semaphore information structure
 *  @param semlabel Label associated with the semaphore
 *  @param name String name of the semaphore
 *
 *  Determine whether the subject identified by the credential can remove
 *  the named POSIX semaphore with label semlabel.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_posixsem_check_unlink_t(
        kauth_cred_t cred,
        struct pseminfo *ps,
        struct label *semlabel,
        const char *name
        );
/**
 *  @brief Access control check for POSIX semaphore wait
 *  @param cred Subject credential
 *  @param ps Pointer to semaphore information structure
 *  @param semlabel Label associated with the semaphore
 *
 *  Determine whether the subject identified by the credential can lock
 *  the named POSIX semaphore with label semlabel.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_posixsem_check_wait_t(
        kauth_cred_t cred,
        struct pseminfo *ps,
        struct label *semlabel
        );
/**
 *  @brief Create a POSIX semaphore label
 *  @param cred Subject credential
 *  @param ps Pointer to semaphore information structure
 *  @param semlabel Label to associate with the new semaphore
 *  @param name String name of the semaphore
 *
 *  Label a new POSIX semaphore.  The label was previously
 *  initialized and associated with the semaphore.  At this time, an
 *  appropriate initial label value should be assigned to the object and
 *  stored in semalabel.
 */
typedef void mpo_posixsem_label_associate_t(
        kauth_cred_t cred,
        struct pseminfo *ps,
        struct label *semlabel,
        const char *name
        );
/**
 *  @brief Destroy POSIX semaphore label
 *  @param label The label to be destroyed
 *
 *  Destroy a POSIX semaphore label.  Since the object is
 *  going out of scope, policy modules should free any internal storage
 *  associated with the label so that it may be destroyed.
 */
typedef void mpo_posixsem_label_destroy_t(
        struct label *label
        );
/**
 *  @brief Initialize POSIX semaphore label
 *  @param label New label to initialize
 *
 *  Initialize the label for a newly instantiated POSIX semaphore. Sleeping
 *  is permitted.
 */
typedef void mpo_posixsem_label_init_t(
        struct label *label
        );
/**
 *  @brief Access control check for POSIX shared memory region create
 *  @param cred Subject credential
 *  @param name String name of the shared memory region
 *
 *  Determine whether the subject identified by the credential can create
 *  the POSIX shared memory region referenced by name.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_posixshm_check_create_t(
        kauth_cred_t cred,
        const char *name
        );
/**
 *  @brief Access control check for mapping POSIX shared memory
 *  @param cred Subject credential
 *  @param ps Pointer to shared memory information structure
 *  @param shmlabel Label associated with the shared memory region
 *  @param prot mmap protections; see mmap(2)
 *  @param flags shmat flags; see shmat(2)
 *
 *  Determine whether the subject identified by the credential can map
 *  the POSIX shared memory segment associated with shmlabel.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_posixshm_check_mmap_t(
        kauth_cred_t cred,
        struct pshminfo *ps,
        struct label *shmlabel,
        int prot,
        int flags
        );
/**
 *  @brief Access control check for POSIX shared memory region open
 *  @param cred Subject credential
 *  @param ps Pointer to shared memory information structure
 *  @param shmlabel Label associated with the shared memory region
 *  @param fflags shm_open(2) open flags ('fflags' encoded)
 *
 *  Determine whether the subject identified by the credential can open
 *  the POSIX shared memory region.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_posixshm_check_open_t(
        kauth_cred_t cred,
        struct pshminfo *ps,
        struct label *shmlabel,
        int fflags
        );
/**
 *  @brief Access control check for POSIX shared memory stat
 *  @param cred Subject credential
 *  @param ps Pointer to shared memory information structure
 *  @param shmlabel Label associated with the shared memory region
 *
 *  Determine whether the subject identified by the credential can obtain
 *  status for the POSIX shared memory segment associated with shmlabel.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_posixshm_check_stat_t(
        kauth_cred_t cred,
        struct pshminfo *ps,
        struct label *shmlabel
        );
/**
 *  @brief Access control check for POSIX shared memory truncate
 *  @param cred Subject credential
 *  @param ps Pointer to shared memory information structure
 *  @param shmlabel Label associated with the shared memory region
 *  @param len Length to truncate or extend shared memory segment
 *
 *  Determine whether the subject identified by the credential can truncate
 *  or extend (to len) the POSIX shared memory segment associated with shmlabel.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_posixshm_check_truncate_t(
        kauth_cred_t cred,
        struct pshminfo *ps,
        struct label *shmlabel,
        off_t len
        );
/**
 *  @brief Access control check for POSIX shared memory unlink
 *  @param cred Subject credential
 *  @param ps Pointer to shared memory information structure
 *  @param shmlabel Label associated with the shared memory region
 *  @param name String name of the shared memory region
 *
 *  Determine whether the subject identified by the credential can delete
 *  the POSIX shared memory segment associated with shmlabel.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_posixshm_check_unlink_t(
        kauth_cred_t cred,
        struct pshminfo *ps,
        struct label *shmlabel,
        const char *name
        );
/**
 *  @brief Create a POSIX shared memory region label
 *  @param cred Subject credential
 *  @param ps Pointer to shared memory information structure
 *  @param shmlabel Label to associate with the new shared memory region
 *  @param name String name of the shared memory region
 *
 *  Label a new POSIX shared memory region.  The label was previously
 *  initialized and associated with the shared memory region.  At this
 *  time, an appropriate initial label value should be assigned to the
 *  object and stored in shmlabel.
 */
typedef void mpo_posixshm_label_associate_t(
        kauth_cred_t cred,
        struct pshminfo *ps,
        struct label *shmlabel,
        const char *name
        );
/**
 *  @brief Destroy POSIX shared memory label
 *  @param label The label to be destroyed
 *
 *  Destroy a POSIX shared memory region label.  Since the
 *  object is going out of scope, policy modules should free any
 *  internal storage associated with the label so that it may be
 *  destroyed.
 */
typedef void mpo_posixshm_label_destroy_t(
        struct label *label
        );
/**
 *  @brief Initialize POSIX Shared Memory region label
 *  @param label New label to initialize
 *
 *  Initialize the label for newly a instantiated POSIX Shared Memory
 *  region. Sleeping is permitted.
 */
typedef void mpo_posixshm_label_init_t(
        struct label *label
        );
/**
 *  @brief Access control check for privileged operations
 *  @param cred Subject credential
 *  @param priv Requested privilege (see sys/priv.h)
 *
 *  Determine whether the subject identified by the credential can perform
 *  a privileged operation.  Privileged operations are allowed if the cred
 *  is the superuser or any policy returns zero for mpo_priv_grant, unless
 *  any policy returns nonzero for mpo_priv_check.
 *
 *  @return Return 0 if access is granted, otherwise EPERM should be returned.
 */
typedef int mpo_priv_check_t(
        kauth_cred_t cred,
        int priv
        );
/**
 *  @brief Grant regular users the ability to perform privileged operations
 *  @param cred Subject credential
 *  @param priv Requested privilege (see sys/priv.h)
 *
 *  Determine whether the subject identified by the credential should be
 *  allowed to perform a privileged operation that in the absense of any
 *  MAC policy it would not be able to perform.  Privileged operations are
 *  allowed if the cred is the superuser or any policy returns zero for
 *  mpo_priv_grant, unless any policy returns nonzero for mpo_priv_check.
 *
 *  Unlike other MAC hooks which can only reduce the privilege of a
 *  credential, this hook raises the privilege of a credential when it
 *  returns 0.  Extreme care must be taken when implementing this hook to
 *  avoid undermining the security of the system.
 *
 *  @return Return 0 if additional privilege is granted, otherwise EPERM
 *  should be returned.
 */
typedef int mpo_priv_grant_t(
        kauth_cred_t cred,
        int priv
        );
/**
 *  @brief Access control check for debugging process
 *  @param cred Subject credential
 *  @param proc Object process
 *
 *  Determine whether the subject identified by the credential can debug
 *  the passed process. This call may be made in a number of situations,
 *  including use of the ptrace(2) and ktrace(2) APIs, as well as for some
 *  types of procfs operations.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch,
 *  EPERM for lack of privilege, or ESRCH to hide visibility of the target.
 */
typedef int mpo_proc_check_debug_t(
        kauth_cred_t cred,
        struct proc *proc
        );
/**
 *  @brief Access control over fork
 *  @param cred Subject credential
 *  @param proc Subject process trying to fork
 *
 *  Determine whether the subject identified is allowed to fork.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_proc_check_fork_t(
        kauth_cred_t cred,
        struct proc *proc
        );
/**
 *  @brief Access control check for setting host special ports.
 *  @param cred Subject credential
 *  @param id The host special port to set
 *  @param port The new value to set for the special port
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_proc_check_set_host_special_port_t(
        kauth_cred_t cred,
        int id,
        struct ipc_port *port
        );
/**
 *  @brief Access control check for setting host exception ports.
 *  @param cred Subject credential
 *  @param exception Exception port to set
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_proc_check_set_host_exception_port_t(
        kauth_cred_t cred,
        unsigned int exception
        );
/**
 *  @brief Access control over pid_suspend and pid_resume
 *  @param cred Subject credential
 *  @param proc Subject process trying to run pid_suspend or pid_resume
 *  @param sr Call is suspend (0) or resume (1)
 *
 *  Determine whether the subject identified is allowed to suspend or resume
 *  other processes.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_proc_check_suspend_resume_t(
        kauth_cred_t cred,
        struct proc *proc,
        int sr
        );
/**
 *  @brief Access control check for retrieving audit information
 *  @param cred Subject credential
 *
 *  Determine whether the subject identified by the credential can get
 *  audit information such as the audit user ID, the preselection mask,
 *  the terminal ID and the audit session ID, using the getaudit() system call.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_proc_check_getaudit_t(
        kauth_cred_t cred
        );
/**
 *  @brief Access control check for retrieving audit user ID
 *  @param cred Subject credential
 *
 *  Determine whether the subject identified by the credential can get
 *  the user identity being used by the auditing system, using the getauid()
 *  system call.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_proc_check_getauid_t(
        kauth_cred_t cred
        );
/**
 *  @brief Access control check for retrieving Login Context ID
 *  @param p0 Calling process
 *  @param p Effected process
 *  @param pid syscall PID argument
 *
 *  Determine if getlcid(2) system call is permitted.
 *
 *  Information returned by this system call is similar to that returned via
 *  process listings etc.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_proc_check_getlcid_t(
        struct proc *p0,
        struct proc *p,
        pid_t pid
        );
/**
 *  @brief Access control check for retrieving ledger information
 *  @param cred Subject credential
 *  @param target Object process
 *  @param op ledger operation
 *
 *  Determine if ledger(2) system call is permitted.
 *
 *  Information returned by this system call is similar to that returned via
 *  process listings etc.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_proc_check_ledger_t(
        kauth_cred_t cred,
        struct proc *target,
        int op
        );
/**
 *  @brief Access control check for retrieving process information.
 *  @param cred Subject credential
 *  @param target Target process (may be null, may be zombie)
 *
 *  Determine if a credential has permission to access process information as defined
 *  by call number and flavor on target process
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_proc_check_proc_info_t(
        kauth_cred_t cred,
        struct proc *target,
        int callnum,
        int flavor
        );
/**
 *  @brief Access control check for retrieving code signing information.
 *  @param cred Subject credential
 *  @param target Target process
 *  @param op Code signing operation being performed
 *
 *  Determine whether the subject identified by the credential should be
 *  allowed to get code signing information about the target process.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_proc_check_get_cs_info_t(
        kauth_cred_t cred,
        struct proc *target,
        unsigned int op
        );
/**
 *  @brief Access control check for setting code signing information.
 *  @param cred Subject credential
 *  @param target Target process
 *  @param op Code signing operation being performed.
 *
 *  Determine whether the subject identified by the credential should be
 *  allowed to set code signing information about the target process.
 *
 *  @return Return 0 if permission is granted, otherwise an appropriate
 *  value of errno should be returned.
 */
typedef int mpo_proc_check_set_cs_info_t(
        kauth_cred_t cred,
        struct proc *target,
        unsigned int op
        );
/**
 *  @brief Access control check for mmap MAP_ANON
 *  @param proc User process requesting the memory
 *  @param cred Subject credential
 *  @param u_addr Start address of the memory range
 *  @param u_size Length address of the memory range
 *  @param prot mmap protections; see mmap(2)
 *  @param flags Type of mapped object; see mmap(2)
 *  @param maxprot Maximum rights
 *
 *  Determine whether the subject identified by the credential should be
 *  allowed to obtain anonymous memory using the specified flags and
 *  protections on the new mapping. MAP_ANON will always be present in the
 *  flags. Certain combinations of flags with a non-NULL addr may
 *  cause a mapping to be rejected before this hook is called. The maxprot field
 *  holds the maximum permissions on the new mapping, a combination of
 *  VM_PROT_READ, VM_PROT_WRITE and VM_PROT_EXECUTE. To avoid overriding prior
 *  access control checks, a policy should only remove flags from maxprot.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EPERM for lack of privilege.
 */
typedef int mpo_proc_check_map_anon_t(
        struct proc *proc,
        kauth_cred_t cred,
        user_addr_t u_addr,
        user_size_t u_size,
        int prot,
        int flags,
        int *maxprot
        );
/**
 *  @brief Access control check for setting memory protections
 *  @param cred Subject credential
 *  @param proc User process requesting the change
 *  @param addr Start address of the memory range
 *  @param size Length address of the memory range
 *  @param prot Memory protections, see mmap(2)
 *
 *  Determine whether the subject identified by the credential should
 *  be allowed to set the specified memory protections on memory mapped
 *  in the process proc.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_proc_check_mprotect_t(
        kauth_cred_t cred,
        struct proc *proc,
        user_addr_t addr,
        user_size_t size,
        int prot
        );
/**
 *  @brief Access control check for changing scheduling parameters
 *  @param cred Subject credential
 *  @param proc Object process
 *
 *  Determine whether the subject identified by the credential can change
 *  the scheduling parameters of the passed process.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch,
 *  EPERM for lack of privilege, or ESRCH to limit visibility.
 */
typedef int mpo_proc_check_sched_t(
        kauth_cred_t cred,
        struct proc *proc
        );
/**
 *  @brief Access control check for setting audit information
 *  @param cred Subject credential
 *  @param ai Audit information
 *
 *  Determine whether the subject identified by the credential can set
 *  audit information such as the the preselection mask, the terminal ID
 *  and the audit session ID, using the setaudit() system call.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_proc_check_setaudit_t(
        kauth_cred_t cred,
        struct auditinfo_addr *ai
        );
/**
 *  @brief Access control check for setting audit user ID
 *  @param cred Subject credential
 *  @param auid Audit user ID
 *
 *  Determine whether the subject identified by the credential can set
 *  the user identity used by the auditing system, using the setauid()
 *  system call.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_proc_check_setauid_t(
        kauth_cred_t cred,
        uid_t auid
        );
/**
 *  @brief Access control check for setting the Login Context
 *  @param p0 Calling process
 *  @param p Effected process
 *  @param pid syscall PID argument
 *  @param lcid syscall LCID argument
 *
 *  Determine if setlcid(2) system call is permitted.
 *
 *  See xnu/bsd/kern/kern_prot.c:setlcid() implementation for example of
 *  decoding syscall arguments to determine action desired by caller.
 *
 *  Five distinct actions are possible: CREATE JOIN LEAVE ADOPT ORPHAN
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_proc_check_setlcid_t(
        struct proc *p0,
        struct proc *p,
        pid_t pid,
        pid_t lcid
        );
/**
 *  @brief Access control check for delivering signal
 *  @param cred Subject credential
 *  @param proc Object process
 *  @param signum Signal number; see kill(2)
 *
 *  Determine whether the subject identified by the credential can deliver
 *  the passed signal to the passed process.
 *
 *  @warning Programs typically expect to be able to send and receive
 *  signals as part or their normal process lifecycle; caution should be
 *  exercised when implementing access controls over signal events.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch,
 *  EPERM for lack of privilege, or ESRCH to limit visibility.
 */
typedef int mpo_proc_check_signal_t(
        kauth_cred_t cred,
        struct proc *proc,
        int signum
        );
/**
 *  @brief Access control check for wait
 *  @param cred Subject credential
 *  @param proc Object process
 *
 *  Determine whether the subject identified by the credential can wait
 *  for process termination.
 *
 *  @warning Caution should be exercised when implementing access
 *  controls for wait, since programs often wait for child processes to
 *  exit.  Failure to be notified of a child process terminating may
 *  cause the parent process to hang, or may produce zombie processes.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_proc_check_wait_t(
        kauth_cred_t cred,
        struct proc *proc
        );
/**
 *  @brief Inform MAC policies that a process has exited.
 *  @param proc Object process
 *
 *  Called after all of the process's threads have terminated and
 *  it has been removed from the process list.  KPI that identifies
 *  the process by pid will fail to find the process; KPI that
 *  identifies the process by the object process pointer functions
 *  normally.  proc_exiting() returns true for the object process.
 */
typedef void mpo_proc_notify_exit_t(
        struct proc *proc
        );
/**
 *  @brief Destroy process label
 *  @param label The label to be destroyed
 *
 *  Destroy a process label.  Since the object is going
 *  out of scope, policy modules should free any internal storage
 *  associated with the label so that it may be destroyed.
 */
typedef void mpo_proc_label_destroy_t(
        struct label *label
        );
/**
 *  @brief Initialize process label
 *  @param label New label to initialize
 *  @see mpo_cred_label_init_t
 *
 *  Initialize the label for a newly instantiated BSD process structure.
 *  Normally, security policies will store the process label in the user
 *  credential rather than here in the process structure.  However,
 *  there are some floating label policies that may need to temporarily
 *  store a label in the process structure until it is safe to update
 *  the user credential label.  Sleeping is permitted.
 */
typedef void mpo_proc_label_init_t(
        struct label *label
        );
/**
 *  @brief Access control check for skywalk flow connect
 *  @param cred Subject credential
 *  @param flow Flow object
 *  @param addr Remote address for flow to send data to
 *  @param type Flow type (e.g. SOCK_STREAM or SOCK_DGRAM)
 *  @param protocol Network protocol (e.g. IPPROTO_TCP)
 *
 *  Determine whether the subject identified by the credential can
 *  create a flow for sending data to the remote host specified by
 *  addr.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_skywalk_flow_check_connect_t(
        kauth_cred_t cred,
        void *flow,
        const struct sockaddr *addr,
        int type,
        int protocol
        );
/**
 *  @brief Access control check for skywalk flow listen
 *  @param cred Subject credential
 *  @param flow Flow object
 *  @param addr Local address for flow to listen on
 *  @param type Flow type (e.g. SOCK_STREAM or SOCK_DGRAM)
 *  @param protocol Network protocol (e.g. IPPROTO_TCP)
 *
 *  Determine whether the subject identified by the credential can
 *  create a flow for receiving data on the local address specified
 *  by addr.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_skywalk_flow_check_listen_t(
        kauth_cred_t cred,
        void *flow,
        const struct sockaddr *addr,
        int type,
        int protocol
        );
/**
 *  @brief Access control check for socket accept
 *  @param cred Subject credential
 *  @param so Object socket
 *  @param socklabel Policy label for socket
 *
 *  Determine whether the subject identified by the credential can accept()
 *  a new connection on the socket from the host specified by addr.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_socket_check_accept_t(
        kauth_cred_t cred,
        socket_t so,
        struct label *socklabel
        );
/**
 *  @brief Access control check for a pending socket accept
 *  @param cred Subject credential
 *  @param so Object socket
 *  @param socklabel Policy label for socket
 *  @param addr Address of the listening socket (coming soon)
 *
 *  Determine whether the subject identified by the credential can accept()
 *  a pending connection on the socket from the host specified by addr.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_socket_check_accepted_t(
        kauth_cred_t cred,
        socket_t so,
        struct label *socklabel,
        struct sockaddr *addr
        );
/**
 *  @brief Access control check for socket bind
 *  @param cred Subject credential
 *  @param so Object socket
 *  @param socklabel Policy label for socket
 *  @param addr Name to assign to the socket
 *
 *  Determine whether the subject identified by the credential can bind()
 *  the name (addr) to the socket.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_socket_check_bind_t(
        kauth_cred_t cred,
        socket_t so,
        struct label *socklabel,
        struct sockaddr *addr
        );
/**
 *  @brief Access control check for socket connect
 *  @param cred Subject credential
 *  @param so Object socket
 *  @param socklabel Policy label for socket
 *  @param addr Name to assign to the socket
 *
 *  Determine whether the subject identified by the credential can
 *  connect() the passed socket to the remote host specified by addr.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_socket_check_connect_t(
        kauth_cred_t cred,
        socket_t so,
        struct label *socklabel,
        struct sockaddr *addr
        );
/**
 *  @brief Access control check for socket() system call.
 *  @param cred Subject credential
 *  @param domain communication domain
 *  @param type socket type
 *  @param protocol socket protocol
 *
 *  Determine whether the subject identified by the credential can
 *  make the socket() call.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_socket_check_create_t(
        kauth_cred_t cred,
        int domain,
        int type,
        int protocol
        );
/**
 *  @brief Access control check for delivering data to a user's receieve queue
 *  @param so The socket data is being delivered to
 *  @param so_label The label of so
 *  @param m The mbuf whose data will be deposited into the receive queue
 *  @param m_label The label of the sender of the data.
 *
 *  A socket has a queue for receiving incoming data.  When a packet arrives
 *  on the wire, it eventually gets deposited into this queue, which the
 *  owner of the socket drains when they read from the socket's file descriptor.
 *
 *  This function determines whether the socket can receive data from
 *  the sender specified by m_label.
 *
 *  @warning There is an outstanding design issue surrounding the placement
 *  of this function.  The check must be placed either before or after the
 *  TCP sequence and ACK counters are updated.  Placing the check before
 *  the counters are updated causes the incoming packet to be resent by
 *  the remote if the check rejects it.  Placing the check after the counters
 *  are updated results in a completely silent drop.  As far as each TCP stack
 *  is concerned the packet was received, however, the data will not be in the
 *  socket's receive queue.  Another consideration is that the current design
 *  requires using the "failed label" occasionally.  In that case, on rejection,
 *  we want the remote TCP to resend the data.  Because of this, we chose to
 *  place this check before the counters are updated, so rejected packets will be
 *  resent by the remote host.
 *
 *  If a policy keeps rejecting the same packet, eventually the connection will
 *  be dropped.  Policies have several options if this design causes problems.
 *  For example, one options is to sanitize the mbuf such that it is acceptable,
 *  then accept it.  That may require negotiation between policies as the
 *  Framework will not know to re-check the packet.
 *
 *  The policy must handle NULL MBUF labels.  This will likely be the case
 *  for non-local TCP sockets for example.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_socket_check_deliver_t(
        socket_t so,
        struct label *so_label,
        struct mbuf *m,
        struct label *m_label
        );
/**
 *  @brief Access control check for socket ioctl.
 *  @param cred Subject credential
 *  @param so Object socket
 *  @param cmd The ioctl command; see ioctl(2)
 *  @param socklabel Policy label for socket
 *
 *  Determine whether the subject identified by the credential can perform
 *  the ioctl operation indicated by cmd on the given socket.
 *
 *  @warning Since ioctl data is opaque from the standpoint of the MAC
 *  framework, and since ioctls can affect many aspects of system
 *  operation, policies must exercise extreme care when implementing
 *  access control checks.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_socket_check_ioctl_t(
        kauth_cred_t cred,
        socket_t so,
        unsigned int cmd,
        struct label *socklabel
        );
/**
 *  @brief Access control check for socket kqfilter
 *  @param cred Subject credential
 *  @param kn Object knote
 *  @param so Object socket
 *  @param socklabel Policy label for socket
 *
 *  Determine whether the subject identified by the credential can
 *  receive the knote on the passed socket.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_socket_check_kqfilter_t(
        kauth_cred_t cred,
        struct knote *kn,
        socket_t so,
        struct label *socklabel
        );
/**
 *  @brief Access control check for socket relabel
 *  @param cred Subject credential
 *  @param so Object socket
 *  @param so_label The current label of so
 *  @param newlabel The label to be assigned to so
 *
 *  Determine whether the subject identified by the credential can
 *  change the label on the socket.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_socket_check_label_update_t(
        kauth_cred_t cred,
        socket_t so,
        struct label *so_label,
        struct label *newlabel
        );
/**
 *  @brief Access control check for socket listen
 *  @param cred Subject credential
 *  @param so Object socket
 *  @param socklabel Policy label for socket
 *
 *  Determine whether the subject identified by the credential can
 *  listen() on the passed socket.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_socket_check_listen_t(
        kauth_cred_t cred,
        socket_t so,
        struct label *socklabel
        );
/**
 *  @brief Access control check for socket receive
 *  @param cred Subject credential
 *  @param so Object socket
 *  @param socklabel Policy label for socket
 *
 *  Determine whether the subject identified by the credential can
 *  receive data from the socket.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_socket_check_receive_t(
        kauth_cred_t cred,
        socket_t so,
        struct label *socklabel
        );

/**
 *  @brief Access control check for socket receive
 *  @param cred Subject credential
 *  @param sock Object socket
 *  @param socklabel Policy label for socket
 *  @param saddr Name of the remote socket
 *
 *  Determine whether the subject identified by the credential can
 *  receive data from the remote host specified by addr.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_socket_check_received_t(
        kauth_cred_t cred,
        struct socket *sock,
        struct label *socklabel,
        struct sockaddr *saddr
        );


/**
 *  @brief Access control check for socket select
 *  @param cred Subject credential
 *  @param so Object socket
 *  @param socklabel Policy label for socket
 *  @param which The operation selected on: FREAD or FWRITE
 *
 *  Determine whether the subject identified by the credential can use the
 *  socket in a call to select().
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_socket_check_select_t(
        kauth_cred_t cred,
        socket_t so,
        struct label *socklabel,
        int which
        );
/**
 *  @brief Access control check for socket send
 *  @param cred Subject credential
 *  @param so Object socket
 *  @param socklabel Policy label for socket
 *  @param addr Address being sent to
 *
 *  Determine whether the subject identified by the credential can send
 *  data to the socket.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_socket_check_send_t(
        kauth_cred_t cred,
        socket_t so,
        struct label *socklabel,
        struct sockaddr *addr
        );
/**
 *  @brief Access control check for retrieving socket status
 *  @param cred Subject credential
 *  @param so Object socket
 *  @param socklabel Policy label for so
 *
 *  Determine whether the subject identified by the credential can
 *  execute the stat() system call on the given socket.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_socket_check_stat_t(
        kauth_cred_t cred,
        socket_t so,
        struct label *socklabel
        );
/**
 *  @brief Access control check for setting socket options
 *  @param cred Subject credential
 *  @param so Object socket
 *  @param socklabel Policy label for so
 *  @param sopt The options being set
 *
 *  Determine whether the subject identified by the credential can
 *  execute the setsockopt system call on the given socket.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_socket_check_setsockopt_t(
        kauth_cred_t cred,
        socket_t so,
        struct label *socklabel,
        struct sockopt *sopt
        );
/**
 *  @brief Access control check for getting socket options
 *  @param cred Subject credential
 *  @param so Object socket
 *  @param socklabel Policy label for so
 *  @param sopt The options to get
 *
 *  Determine whether the subject identified by the credential can
 *  execute the getsockopt system call on the given socket.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_socket_check_getsockopt_t(
        kauth_cred_t cred,
        socket_t so,
        struct label *socklabel,
        struct sockopt *sopt
        );
/**
 *  @brief Label a socket
 *  @param oldsock Listening socket
 *  @param oldlabel Policy label associated with oldsock
 *  @param newsock New socket
 *  @param newlabel Policy label associated with newsock
 *
 *  A new socket is created when a connection is accept(2)ed.  This
 *  function labels the new socket based on the existing listen(2)ing
 *  socket.
 */
typedef void mpo_socket_label_associate_accept_t(
        socket_t oldsock,
        struct label *oldlabel,
        socket_t newsock,
        struct label *newlabel
        );
/**
 *  @brief Assign a label to a new socket
 *  @param cred Credential of the owning process
 *  @param so The socket being labeled
 *  @param solabel The label
 *  @warning cred can be NULL
 *
 *  Set the label on a newly created socket from the passed subject
 *  credential.  This call is made when a socket is created.  The
 *  credentials may be null if the socket is being created by the
 *  kernel.
 */
typedef void mpo_socket_label_associate_t(
        kauth_cred_t cred,
        socket_t so,
        struct label *solabel
        );
/**
 *  @brief Copy a socket label
 *  @param src Source label
 *  @param dest Destination label
 *
 *  Copy the socket label information in src into dest.
 */
typedef void mpo_socket_label_copy_t(
        struct label *src,
        struct label *dest
        );
/**
 *  @brief Destroy socket label
 *  @param label The label to be destroyed
 *
 *  Destroy a socket label.  Since the object is going out of
 *  scope, policy modules should free any internal storage associated
 *  with the label so that it may be destroyed.
 */
typedef void mpo_socket_label_destroy_t(
        struct label *label
        );
/**
 *  @brief Externalize a socket label
 *  @param label Label to be externalized
 *  @param element_name Name of the label namespace for which labels should be
 *  externalized
 *  @param sb String buffer to be filled with a text representation of label
 *
 *  Produce an externalized socket label based on the label structure passed.
 *  An externalized label consists of a text representation of the label
 *  contents that can be used with userland applications and read by the
 *  user.  If element_name does not match a namespace managed by the policy,
 *  simply return 0. Only return nonzero if an error occurs while externalizing
 *  the label data.
 *
 *  @return In the event of an error, an appropriate value for errno
 *  should be returned, otherwise return 0 upon success.
 */
typedef int mpo_socket_label_externalize_t(
        struct label *label,
        char *element_name,
        struct sbuf *sb
        );
/**
 *  @brief Initialize socket label
 *  @param label New label to initialize
 *  @param waitok Malloc flags
 *
 *  Initialize the label of a newly instantiated socket.  The waitok
 *  field may be one of M_WAITOK and M_NOWAIT, and should be employed to
 *  avoid performing a sleeping malloc(9) during this initialization
 *  call.  It it not always safe to sleep during this entry point.
 *
 *  @warning Since it is possible for the waitok flags to be set to
 *  M_NOWAIT, the malloc operation may fail.
 *
 *  @return In the event of an error, an appropriate value for errno
 *  should be returned, otherwise return 0 upon success.
 */
typedef int mpo_socket_label_init_t(
        struct label *label,
        int waitok
        );
/**
 *  @brief Internalize a socket label
 *  @param label Label to be filled in
 *  @param element_name Name of the label namespace for which the label should
 *  be internalized
 *  @param element_data Text data to be internalized
 *
 *  Produce an internal socket label structure based on externalized label
 *  data in text format.
 *
 *  The policy's internalize entry points will be called only if the
 *  policy has registered interest in the label namespace.
 *
 *  @return In the event of an error, an appropriate value for errno
 *  should be returned, otherwise return 0 upon success.
 */
typedef int mpo_socket_label_internalize_t(
        struct label *label,
        char *element_name,
        char *element_data
        );
/**
 *  @brief Relabel socket
 *  @param cred Subject credential
 *  @param so Object; socket
 *  @param so_label Current label of the socket
 *  @param newlabel The label to be assigned to so
 *
 *  The subject identified by the credential has previously requested
 *  and was authorized to relabel the socket; this entry point allows
 *  policies to perform the actual label update operation.
 *
 *  @warning XXX This entry point will likely change in future versions.
 */
typedef void mpo_socket_label_update_t(
        kauth_cred_t cred,
        socket_t so,
        struct label *so_label,
        struct label *newlabel
        );
/**
 *  @brief Set the peer label on a socket from mbuf
 *  @param m Mbuf chain received on socket so
 *  @param m_label Label for m
 *  @param so Current label for the socket
 *  @param so_label Policy label to be filled out for the socket
 *
 *  Set the peer label of a socket based on the label of the sender of the
 *  mbuf.
 *
 *  This is called for every TCP/IP packet received.  The first call for a given
 *  socket operates on a newly initialized label, and subsequent calls operate
 *  on existing label data.
 *
 *  @warning Because this can affect performance significantly, it has
 *  different sematics than other 'set' operations.  Typically, 'set' operations
 *  operate on newly initialzed labels and policies do not need to worry about
 *  clobbering existing values.  In this case, it is too inefficient to
 *  initialize and destroy a label every time data is received for the socket.
 *  Instead, it is up to the policies to determine how to replace the label data.
 *  Most policies should be able to replace the data inline.
 */
typedef void mpo_socketpeer_label_associate_mbuf_t(
        struct mbuf *m,
        struct label *m_label,
        socket_t so,
        struct label *so_label
        );
/**
 *  @brief Set the peer label on a socket from socket
 *  @param source Local socket
 *  @param sourcelabel Policy label for source
 *  @param target Peer socket
 *  @param targetlabel Policy label to fill in for target
 *
 *  Set the peer label on a stream UNIX domain socket from the passed
 *  remote socket endpoint. This call will be made when the socket pair
 *  is connected, and will be made for both endpoints.
 *
 *  Note that this call is only made on connection; it is currently not updated
 *  during communication.
 */
typedef void mpo_socketpeer_label_associate_socket_t(
        socket_t source,
        struct label *sourcelabel,
        socket_t target,
        struct label *targetlabel
        );
/**
 *  @brief Destroy socket peer label
 *  @param label The peer label to be destroyed
 *
 *  Destroy a socket peer label.  Since the object is going out of
 *  scope, policy modules should free any internal storage associated
 *  with the label so that it may be destroyed.
 */
typedef void mpo_socketpeer_label_destroy_t(
        struct label *label
        );
/**
 *  @brief Externalize a socket peer label
 *  @param label Label to be externalized
 *  @param element_name Name of the label namespace for which labels should be
 *  externalized
 *  @param sb String buffer to be filled with a text representation of label
 *
 *  Produce an externalized socket peer label based on the label structure
 *  passed. An externalized label consists of a text representation of the
 *  label contents that can be used with userland applications and read by the
 *  user.  If element_name does not match a namespace managed by the policy,
 *  simply return 0. Only return nonzero if an error occurs while externalizing
 *  the label data.
 *
 *  @return In the event of an error, an appropriate value for errno
 *  should be returned, otherwise return 0 upon success.
 */
typedef int mpo_socketpeer_label_externalize_t(
        struct label *label,
        char *element_name,
        struct sbuf *sb
        );
/**
 *  @brief Initialize socket peer label
 *  @param label New label to initialize
 *  @param waitok Malloc flags
 *
 *  Initialize the peer label of a newly instantiated socket.  The
 *  waitok field may be one of M_WAITOK and M_NOWAIT, and should be
 *  employed to avoid performing a sleeping malloc(9) during this
 *  initialization call.  It it not always safe to sleep during this
 *  entry point.
 *
 *  @warning Since it is possible for the waitok flags to be set to
 *  M_NOWAIT, the malloc operation may fail.
 *
 *  @return In the event of an error, an appropriate value for errno
 *  should be returned, otherwise return 0 upon success.
 */
typedef int mpo_socketpeer_label_init_t(
        struct label *label,
        int waitok
        );
/**
 *  @brief Access control check for enabling accounting
 *  @param cred Subject credential
 *  @param vp Accounting file
 *  @param vlabel Label associated with vp
 *
 *  Determine whether the subject should be allowed to enable accounting,
 *  based on its label and the label of the accounting log file.  See
 *  acct(5) for more information.
 *
 *  As accounting is disabled by passing NULL to the acct(2) system call,
 *  the policy should be prepared for both 'vp' and 'vlabel' to be NULL.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_system_check_acct_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *vlabel
        );
/**
 *  @brief Access control check for audit
 *  @param cred Subject credential
 *  @param record Audit record
 *  @param length Audit record length
 *
 *  Determine whether the subject identified by the credential can submit
 *  an audit record for inclusion in the audit log via the audit() system call.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_system_check_audit_t(
        kauth_cred_t cred,
        void *record,
        int length
        );
/**
 *  @brief Access control check for controlling audit
 *  @param cred Subject credential
 *  @param vp Audit file
 *  @param vl Label associated with vp
 *
 *  Determine whether the subject should be allowed to enable auditing using
 *  the auditctl() system call, based on its label and the label of the proposed
 *  audit file.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_system_check_auditctl_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *vl
        );
/**
 *  @brief Access control check for manipulating auditing
 *  @param cred Subject credential
 *  @param cmd Audit control command
 *
 *  Determine whether the subject identified by the credential can perform
 *  the audit subsystem control operation cmd via the auditon() system call.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_system_check_auditon_t(
        kauth_cred_t cred,
        int cmd
        );
/**
 *  @brief Access control check for using CHUD facilities
 *  @param cred Subject credential
 *
 *  Determine whether the subject identified by the credential can perform
 *  performance-related tasks using the CHUD system call.  This interface is
 *  deprecated.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_system_check_chud_t(
        kauth_cred_t cred
        );
/**
 *  @brief Access control check for obtaining the host control port
 *  @param cred Subject credential
 *
 *  Determine whether the subject identified by the credential can
 *  obtain the host control port.
 *
 *  @return Return 0 if access is granted, or non-zero otherwise.
 */
typedef int mpo_system_check_host_priv_t(
        kauth_cred_t cred
        );
/**
 *  @brief Access control check for obtaining system information
 *  @param cred Subject credential
 *  @param info_type A description of the information requested
 *
 *  Determine whether the subject identified by the credential should be
 *  allowed to obtain information about the system.
 *
 *  This is a generic hook that can be used in a variety of situations where
 *  information is being returned that might be considered sensitive.
 *  Rather than adding a new MAC hook for every such interface, this hook can
 *  be called with a string identifying the type of information requested.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_system_check_info_t(
        kauth_cred_t cred,
        const char *info_type
        );
/**
 *  @brief Access control check for calling NFS services
 *  @param cred Subject credential
 *
 *  Determine whether the subject identified by the credential should be
 *  allowed to call nfssrv(2).
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_system_check_nfsd_t(
        kauth_cred_t cred
        );
/**
 *  @brief Access control check for reboot
 *  @param cred Subject credential
 *  @param howto howto parameter from reboot(2)
 *
 *  Determine whether the subject identified by the credential should be
 *  allowed to reboot the system in the specified manner.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_system_check_reboot_t(
        kauth_cred_t cred,
        int howto
        );
/**
 *  @brief Access control check for setting system clock
 *  @param cred Subject credential
 *
 *  Determine whether the subject identified by the credential should be
 *  allowed to set the system clock.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_system_check_settime_t(
        kauth_cred_t cred
        );
/**
 *  @brief Access control check for removing swap devices
 *  @param cred Subject credential
 *  @param vp Swap device
 *  @param label Label associated with vp
 *
 *  Determine whether the subject identified by the credential should be
 *  allowed to remove vp as a swap device.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_system_check_swapoff_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label
        );
/**
 *  @brief Access control check for adding swap devices
 *  @param cred Subject credential
 *  @param vp Swap device
 *  @param label Label associated with vp
 *
 *  Determine whether the subject identified by the credential should be
 *  allowed to add vp as a swap device.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_system_check_swapon_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label
        );
/**
 *  @brief Access control check for sysctl
 *  @param cred Subject credential
 *  @param namestring String representation of sysctl name.
 *  @param name Integer name; see sysctl(3)
 *  @param namelen Length of name array of integers; see sysctl(3)
 *  @param old 0 or address where to store old value; see sysctl(3)
 *  @param oldlen Length of old buffer; see sysctl(3)
 *  @param newvalue 0 or address of new value; see sysctl(3)
 *  @param newlen Length of new buffer; see sysctl(3)
 *
 *  Determine whether the subject identified by the credential should be
 *  allowed to make the specified sysctl(3) transaction.
 *
 *  The sysctl(3) call specifies that if the old value is not desired,
 *  oldp and oldlenp should be set to NULL.  Likewise, if a new value is
 *  not to be set, newp should be set to NULL and newlen set to 0.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_system_check_sysctlbyname_t(
        kauth_cred_t cred,
        const char *namestring,
        int *name,
        u_int namelen,
        user_addr_t old,        /* NULLOK */
        size_t oldlen,
        user_addr_t newvalue,   /* NULLOK */
        size_t newlen
        );
/**
 *  @brief Access control check for kas_info
 *  @param cred Subject credential
 *  @param selector Category of information to return. See kas_info.h
 *
 *  Determine whether the subject identified by the credential can perform
 *  introspection of the kernel address space layout for
 *  debugging/performance analysis.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_system_check_kas_info_t(
        kauth_cred_t cred,
        int selector
        );
/**
 *  @brief Create a System V message label
 *  @param cred Subject credential
 *  @param msqptr The message queue the message will be placed in
 *  @param msqlabel The label of the message queue
 *  @param msgptr The message
 *  @param msglabel The label of the message
 *
 *  Label the message as its placed in the message queue.
 */
typedef void mpo_sysvmsg_label_associate_t(
        kauth_cred_t cred,
        struct msqid_kernel *msqptr,
        struct label *msqlabel,
        struct msg *msgptr,
        struct label *msglabel
        );
/**
 *  @brief Destroy System V message label
 *  @param label The label to be destroyed
 *
 *  Destroy a System V message label.  Since the object is
 *  going out of scope, policy modules should free any internal storage
 *  associated with the label so that it may be destroyed.
 */
typedef void mpo_sysvmsg_label_destroy_t(
        struct label *label
        );
/**
 *  @brief Initialize System V message label
 *  @param label New label to initialize
 *
 *  Initialize the label for a newly instantiated System V message.
 */
typedef void mpo_sysvmsg_label_init_t(
        struct label *label
        );
/**
 *  @brief Clean up a System V message label
 *  @param label The label to be destroyed
 *
 *  Clean up a System V message label.  Darwin pre-allocates
 *  messages at system boot time and re-uses them rather than
 *  allocating new ones.  Before messages are returned to the "free
 *  pool", policies can cleanup or overwrite any information present in
 *  the label.
 */
typedef void mpo_sysvmsg_label_recycle_t(
        struct label *label
        );
/**
 *  @brief Access control check for System V message enqueuing
 *  @param cred Subject credential
 *  @param msgptr The message
 *  @param msglabel The message's label
 *  @param msqptr The message queue
 *  @param msqlabel The message queue's label
 *
 *  Determine whether the subject identified by the credential can add the
 *  given message to the given message queue.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_sysvmsq_check_enqueue_t(
        kauth_cred_t cred,
        struct msg *msgptr,
        struct label *msglabel,
        struct msqid_kernel *msqptr,
        struct label *msqlabel
        );
/**
 *  @brief Access control check for System V message reception
 *  @param cred The credential of the intended recipient
 *  @param msgptr The message
 *  @param msglabel The message's label
 *
 *  Determine whether the subject identified by the credential can receive
 *  the given message.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_sysvmsq_check_msgrcv_t(
        kauth_cred_t cred,
        struct msg *msgptr,
        struct label *msglabel
        );
/**
 *  @brief Access control check for System V message queue removal
 *  @param cred The credential of the caller
 *  @param msgptr The message
 *  @param msglabel The message's label
 *
 *  System V message queues are removed using the msgctl() system call.
 *  The system will iterate over each messsage in the queue, calling this
 *  function for each, to determine whether the caller has the appropriate
 *  credentials.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_sysvmsq_check_msgrmid_t(
        kauth_cred_t cred,
        struct msg *msgptr,
        struct label *msglabel
        );
/**
 *  @brief Access control check for msgctl()
 *  @param cred The credential of the caller
 *  @param msqptr The message queue
 *  @param msqlabel The message queue's label
 *
 *  This access check is performed to validate calls to msgctl().
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_sysvmsq_check_msqctl_t(
        kauth_cred_t cred,
        struct msqid_kernel *msqptr,
        struct label *msqlabel,
        int cmd
        );
/**
 *  @brief Access control check to get a System V message queue
 *  @param cred The credential of the caller
 *  @param msqptr The message queue requested
 *  @param msqlabel The message queue's label
 *
 *  On a call to msgget(), if the queue requested already exists,
 *  and it is a public queue, this check will be performed before the
 *  queue's ID is returned to the user.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_sysvmsq_check_msqget_t(
        kauth_cred_t cred,
        struct msqid_kernel *msqptr,
        struct label *msqlabel
        );
/**
 *  @brief Access control check to receive a System V message from the given queue
 *  @param cred The credential of the caller
 *  @param msqptr The message queue to receive from
 *  @param msqlabel The message queue's label
 *
 *  On a call to msgrcv(), this check is performed to determine whether the
 *  caller has receive rights on the given queue.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_sysvmsq_check_msqrcv_t(
        kauth_cred_t cred,
        struct msqid_kernel *msqptr,
        struct label *msqlabel
        );
/**
 *  @brief Access control check to send a System V message to the given queue
 *  @param cred The credential of the caller
 *  @param msqptr The message queue to send to
 *  @param msqlabel The message queue's label
 *
 *  On a call to msgsnd(), this check is performed to determine whether the
 *  caller has send rights on the given queue.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_sysvmsq_check_msqsnd_t(
        kauth_cred_t cred,
        struct msqid_kernel *msqptr,
        struct label *msqlabel
        );
/**
 *  @brief Create a System V message queue label
 *  @param cred Subject credential
 *  @param msqptr The message queue
 *  @param msqlabel The label of the message queue
 *
 */
typedef void mpo_sysvmsq_label_associate_t(
        kauth_cred_t cred,
        struct msqid_kernel *msqptr,
        struct label *msqlabel
        );
/**
 *  @brief Destroy System V message queue label
 *  @param label The label to be destroyed
 *
 *  Destroy a System V message queue label.  Since the object is
 *  going out of scope, policy modules should free any internal storage
 *  associated with the label so that it may be destroyed.
 */
typedef void mpo_sysvmsq_label_destroy_t(
        struct label *label
        );
/**
 *  @brief Initialize System V message queue label
 *  @param label New label to initialize
 *
 *  Initialize the label for a newly instantiated System V message queue.
 */
typedef void mpo_sysvmsq_label_init_t(
        struct label *label
        );
/**
 *  @brief Clean up a System V message queue label
 *  @param label The label to be destroyed
 *
 *  Clean up a System V message queue label.  Darwin pre-allocates
 *  message queues at system boot time and re-uses them rather than
 *  allocating new ones.  Before message queues are returned to the "free
 *  pool", policies can cleanup or overwrite any information present in
 *  the label.
 */
typedef void mpo_sysvmsq_label_recycle_t(
        struct label *label
        );
/**
 *  @brief Access control check for System V semaphore control operation
 *  @param cred Subject credential
 *  @param semakptr Pointer to semaphore identifier
 *  @param semaklabel Label associated with semaphore
 *  @param cmd Control operation to be performed; see semctl(2)
 *
 *  Determine whether the subject identified by the credential can perform
 *  the operation indicated by cmd on the System V semaphore semakptr.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_sysvsem_check_semctl_t(
        kauth_cred_t cred,
        struct semid_kernel *semakptr,
        struct label *semaklabel,
        int cmd
        );
/**
 *  @brief Access control check for obtaining a System V semaphore
 *  @param cred Subject credential
 *  @param semakptr Pointer to semaphore identifier
 *  @param semaklabel Label to associate with the semaphore
 *
 *  Determine whether the subject identified by the credential can
 *  obtain a System V semaphore.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_sysvsem_check_semget_t(
        kauth_cred_t cred,
        struct semid_kernel *semakptr,
        struct label *semaklabel
        );
/**
 *  @brief Access control check for System V semaphore operations
 *  @param cred Subject credential
 *  @param semakptr Pointer to semaphore identifier
 *  @param semaklabel Label associated with the semaphore
 *  @param accesstype Flags to indicate access (read and/or write)
 *
 *  Determine whether the subject identified by the credential can
 *  perform the operations on the System V semaphore indicated by
 *  semakptr.  The accesstype flags hold the maximum set of permissions
 *  from the sem_op array passed to the semop system call.  It may
 *  contain SEM_R for read-only operations or SEM_A for read/write
 *  operations.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_sysvsem_check_semop_t(
        kauth_cred_t cred,
        struct semid_kernel *semakptr,
        struct label *semaklabel,
        size_t accesstype
        );
/**
 *  @brief Create a System V semaphore label
 *  @param cred Subject credential
 *  @param semakptr The semaphore being created
 *  @param semalabel Label to associate with the new semaphore
 *
 *  Label a new System V semaphore.  The label was previously
 *  initialized and associated with the semaphore.  At this time, an
 *  appropriate initial label value should be assigned to the object and
 *  stored in semalabel.
 */
typedef void mpo_sysvsem_label_associate_t(
        kauth_cred_t cred,
        struct semid_kernel *semakptr,
        struct label *semalabel
        );
/**
 *  @brief Destroy System V semaphore label
 *  @param label The label to be destroyed
 *
 *  Destroy a System V semaphore label.  Since the object is
 *  going out of scope, policy modules should free any internal storage
 *  associated with the label so that it may be destroyed.
 */
typedef void mpo_sysvsem_label_destroy_t(
        struct label *label
        );
/**
 *  @brief Initialize System V semaphore label
 *  @param label New label to initialize
 *
 *  Initialize the label for a newly instantiated System V semaphore.  Sleeping
 *  is permitted.
 */
typedef void mpo_sysvsem_label_init_t(
        struct label *label
        );
/**
 *  @brief Clean up a System V semaphore label
 *  @param label The label to be cleaned
 *
 *  Clean up a System V semaphore label.  Darwin pre-allocates
 *  semaphores at system boot time and re-uses them rather than
 *  allocating new ones.  Before semaphores are returned to the "free
 *  pool", policies can cleanup or overwrite any information present in
 *  the label.
 */
typedef void mpo_sysvsem_label_recycle_t(
        struct label *label
        );
/**
 *  @brief Access control check for mapping System V shared memory
 *  @param cred Subject credential
 *  @param shmsegptr Pointer to shared memory segment identifier
 *  @param shmseglabel Label associated with the shared memory segment
 *  @param shmflg shmat flags; see shmat(2)
 *
 *  Determine whether the subject identified by the credential can map
 *  the System V shared memory segment associated with shmsegptr.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_sysvshm_check_shmat_t(
        kauth_cred_t cred,
        struct shmid_kernel *shmsegptr,
        struct label *shmseglabel,
        int shmflg
        );
/**
 *  @brief Access control check for System V shared memory control operation
 *  @param cred Subject credential
 *  @param shmsegptr Pointer to shared memory segment identifier
 *  @param shmseglabel Label associated with the shared memory segment
 *  @param cmd Control operation to be performed; see shmctl(2)
 *
 *  Determine whether the subject identified by the credential can perform
 *  the operation indicated by cmd on the System V shared memory segment
 *  shmsegptr.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_sysvshm_check_shmctl_t(
        kauth_cred_t cred,
        struct shmid_kernel *shmsegptr,
        struct label *shmseglabel,
        int cmd
        );
/**
 *  @brief Access control check for unmapping System V shared memory
 *  @param cred Subject credential
 *  @param shmsegptr Pointer to shared memory segment identifier
 *  @param shmseglabel Label associated with the shared memory segment
 *
 *  Determine whether the subject identified by the credential can unmap
 *  the System V shared memory segment associated with shmsegptr.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_sysvshm_check_shmdt_t(
        kauth_cred_t cred,
        struct shmid_kernel *shmsegptr,
        struct label *shmseglabel
        );
/**
 *  @brief Access control check obtaining System V shared memory identifier
 *  @param cred Subject credential
 *  @param shmsegptr Pointer to shared memory segment identifier
 *  @param shmseglabel Label associated with the shared memory segment
 *  @param shmflg shmget flags; see shmget(2)
 *
 *  Determine whether the subject identified by the credential can get
 *  the System V shared memory segment address.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_sysvshm_check_shmget_t(
        kauth_cred_t cred,
        struct shmid_kernel *shmsegptr,
        struct label *shmseglabel,
        int shmflg
        );
/**
 *  @brief Create a System V shared memory region label
 *  @param cred Subject credential
 *  @param shmsegptr The shared memory region being created
 *  @param shmlabel Label to associate with the new shared memory region
 *
 *  Label a new System V shared memory region.  The label was previously
 *  initialized and associated with the shared memory region.  At this
 *  time, an appropriate initial label value should be assigned to the
 *  object and stored in shmlabel.
 */
typedef void mpo_sysvshm_label_associate_t(
        kauth_cred_t cred,
        struct shmid_kernel *shmsegptr,
        struct label *shmlabel
        );
/**
 *  @brief Destroy System V shared memory label
 *  @param label The label to be destroyed
 *
 *  Destroy a System V shared memory region label.  Since the
 *  object is going out of scope, policy modules should free any
 *  internal storage associated with the label so that it may be
 *  destroyed.
 */
typedef void mpo_sysvshm_label_destroy_t(
        struct label *label
        );
/**
 *  @brief Initialize System V Shared Memory region label
 *  @param label New label to initialize
 *
 *  Initialize the label for a newly instantiated System V Shared Memory
 *  region.  Sleeping is permitted.
 */
typedef void mpo_sysvshm_label_init_t(
        struct label *label
        );
/**
 *  @brief Clean up a System V Share Memory Region label
 *  @param shmlabel The label to be cleaned
 *
 *  Clean up a System V Shared Memory Region label.  Darwin
 *  pre-allocates these objects at system boot time and re-uses them
 *  rather than allocating new ones.  Before the memory regions are
 *  returned to the "free pool", policies can cleanup or overwrite any
 *  information present in the label.
 */
typedef void mpo_sysvshm_label_recycle_t(
        struct label *shmlabel
        );
/**
 *  @brief Access control check for getting a process's task name
 *  @param cred Subject credential
 *  @param p Object process
 *
 *  Determine whether the subject identified by the credential can get
 *  the passed process's task name port.
 *  This call is used by the task_name_for_pid(2) API.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch,
 *  EPERM for lack of privilege, or ESRCH to hide visibility of the target.
 */
typedef int mpo_proc_check_get_task_name_t(
        kauth_cred_t cred,
        struct proc *p
        );
/**
 *  @brief Access control check for getting a process's task port
 *  @param cred Subject credential
 *  @param p Object process
 *
 *  Determine whether the subject identified by the credential can get
 *  the passed process's task control port.
 *  This call is used by the task_for_pid(2) API.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch,
 *  EPERM for lack of privilege, or ESRCH to hide visibility of the target.
 */
typedef int mpo_proc_check_get_task_t(
        kauth_cred_t cred,
        struct proc *p
        );

/**
 *  @brief Access control check for exposing a process's task port
 *  @param cred Subject credential
 *  @param p Object process
 *
 *  Determine whether the subject identified by the credential can expose
 *  the passed process's task control port.
 *  This call is used by the accessor APIs like processor_set_tasks() and
 *  processor_set_threads().
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch,
 *  EPERM for lack of privilege, or ESRCH to hide visibility of the target.
 */
typedef int mpo_proc_check_expose_task_t(
        kauth_cred_t cred,
        struct proc *p
        );

/**
 *  @brief Check whether task's IPC may inherit across process exec
 *  @param p current process instance
 *  @param cur_vp vnode pointer to current instance
 *  @param cur_offset offset of binary of currently executing image
 *  @param img_vp vnode pointer to to be exec'ed image
 *  @param img_offset offset into file which is selected for execution
 *  @param scriptvp vnode pointer of script file if any.
 *  @return Return 0 if access is granted.
 *       EPERM     if parent does not have any entitlements.
 *       EACCESS   if mismatch in entitlements
 */
typedef int mpo_proc_check_inherit_ipc_ports_t(
        struct proc *p,
        struct vnode *cur_vp,
        off_t cur_offset,
        struct vnode *img_vp,
        off_t img_offset,
        struct vnode *scriptvp
        );

/**
 *  @brief Privilege check for a process to run invalid
 *  @param p Object process
 *
 *  Determine whether the process may execute even though the system determined
 *  that it is untrusted (eg unidentified / modified code).
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_proc_check_run_cs_invalid_t(
        struct proc *p
        );

/**
 *  @brief Notification a process is finished with exec and will jump to userspace
 *  @param p Object process
 *
 *  Notifies all MAC policies that a process has completed an exec and is about to
 *  jump to userspace to continue execution. This may result in process termination
 *  via signals. Hook is designed to hold no/minimal locks so it can be used for any
 *  necessary upcalls.
 */
typedef void mpo_proc_notify_exec_complete_t(
        struct proc *p
        );

/**
 *  @brief Perform MAC-related events when a thread returns to user space
 *  @param thread Mach (not BSD) thread that is returning
 *
 *  This entry point permits policy modules to perform MAC-related
 *  events when a thread returns to user space, via a system call
 *  return or trap return.
 */
typedef void mpo_thread_userret_t(
        struct thread *thread
        );

/**
 *  @brief Check vnode access
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param label Label for vp
 *  @param acc_mode access(2) flags
 *
 *  Determine how invocations of access(2) and related calls by the
 *  subject identified by the credential should return when performed
 *  on the passed vnode using the passed access flags. This should
 *  generally be implemented using the same semantics used in
 *  mpo_vnode_check_open.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_access_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label,
        int acc_mode
        );
/**
 *  @brief Access control check for changing working directory
 *  @param cred Subject credential
 *  @param dvp Object; vnode to chdir(2) into
 *  @param dlabel Policy label for dvp
 *
 *  Determine whether the subject identified by the credential can change
 *  the process working directory to the passed vnode.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_chdir_t(
        kauth_cred_t cred,
        struct vnode *dvp,
        struct label *dlabel
        );
/**
 *  @brief Access control check for changing root directory
 *  @param cred Subject credential
 *  @param dvp Directory vnode
 *  @param dlabel Policy label associated with dvp
 *  @param cnp Component name for dvp
 *
 *  Determine whether the subject identified by the credential should be
 *  allowed to chroot(2) into the specified directory (dvp).
 *
 *  @return In the event of an error, an appropriate value for errno
 *  should be returned, otherwise return 0 upon success.
 */
typedef int mpo_vnode_check_chroot_t(
        kauth_cred_t cred,
        struct vnode *dvp,
        struct label *dlabel,
        struct componentname *cnp
        );
/**
 *  @brief Access control check for creating clone
 *  @param cred Subject credential
 *  @param dvp Vnode of directory to create the clone in
 *  @param dlabel Policy label associated with dvp
 *  @param vp Vnode of the file to clone from
 *  @param label Policy label associated with vp
 *  @param cnp Component name for the clone being created
 *
 *  Determine whether the subject identified by the credential should be
 *  allowed to create a clone of the vnode vp with the name specified by cnp.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_vnode_check_clone_t(
        kauth_cred_t cred,
        struct vnode *dvp,
        struct label *dlabel,
        struct vnode *vp,
        struct label *label,
        struct componentname *cnp
        );
/**
 *  @brief Access control check for creating vnode
 *  @param cred Subject credential
 *  @param dvp Directory vnode
 *  @param dlabel Policy label for dvp
 *  @param cnp Component name for dvp
 *  @param vap vnode attributes for vap
 *
 *  Determine whether the subject identified by the credential can create
 *  a vnode with the passed parent directory, passed name information,
 *  and passed attribute information. This call may be made in a number of
 *  situations, including as a result of calls to open(2) with O_CREAT,
 *  mknod(2), mkfifo(2), and others.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_create_t(
        kauth_cred_t cred,
        struct vnode *dvp,
        struct label *dlabel,
        struct componentname *cnp,
        struct vnode_attr *vap
        );
/**
 *  @brief Access control check for deleting extended attribute
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param vlabel Label associated with vp
 *  @param name Extended attribute name
 *
 *  Determine whether the subject identified by the credential can delete
 *  the extended attribute from the passed vnode.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_deleteextattr_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *vlabel,
        const char *name
        );
/**
 *  @brief Access control check for exchanging file data
 *  @param cred Subject credential
 *  @param v1 vnode 1 to swap
 *  @param vl1 Policy label for v1
 *  @param v2 vnode 2 to swap
 *  @param vl2 Policy label for v2
 *
 *  Determine whether the subject identified by the credential can swap the data
 *  in the two supplied vnodes.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_exchangedata_t(
        kauth_cred_t cred,
        struct vnode *v1,
        struct label *vl1,
        struct vnode *v2,
        struct label *vl2
        );
/**
 *  @brief Access control check for executing the vnode
 *  @param cred Subject credential
 *  @param vp Object vnode to execute
 *  @param scriptvp Script being executed by interpreter, if any.
 *  @param vnodelabel Label corresponding to vp
 *  @param scriptlabel Script vnode label
 *  @param execlabel Userspace provided execution label
 *  @param cnp Component name for file being executed
 *  @param macpolicyattr MAC policy-specific spawn attribute data.
 *  @param macpolicyattrlen Length of policy-specific spawn attribute data.
 *
 *  Determine whether the subject identified by the credential can execute
 *  the passed vnode. Determination of execute privilege is made separately
 *  from decisions about any process label transitioning event.
 *
 *  The final label, execlabel, corresponds to a label supplied by a
 *  user space application through the use of the mac_execve system call.
 *  This label will be NULL if the user application uses the the vendor
 *  execve(2) call instead of the MAC Framework mac_execve() call.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_exec_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct vnode *scriptvp,
        struct label *vnodelabel,
        struct label *scriptlabel,
        struct label *execlabel,        /* NULLOK */
        struct componentname *cnp,
        u_int *csflags,
        void *macpolicyattr,
        size_t macpolicyattrlen
        );
/**
 *  @brief Access control check for fsgetpath
 *  @param cred Subject credential
 *  @param vp Vnode for which a path will be returned
 *  @param label Label associated with the vnode
 *
 *  Determine whether the subject identified by the credential can get the path
 *  of the given vnode with fsgetpath.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_vnode_check_fsgetpath_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label
        );
/**
 *  @brief Access control check for retrieving file attributes
 *  @param active_cred Subject credential
 *  @param file_cred Credential associated with the struct fileproc
 *  @param vp Object vnode
 *  @param vlabel Policy label for vp
 *  @param va Vnode attributes to retrieve
 *
 *  Determine whether the subject identified by the credential can
 *  get information about the passed vnode.  The active_cred hold
 *  the credentials of the subject performing the operation, and
 *  file_cred holds the credentials of the subject that originally
 *  opened the file. This check happens during stat(), lstat(),
 *  fstat(), and getattrlist() syscalls.  See <sys/vnode.h> for
 *  definitions of the attributes.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 *
 *  @note Policies may change the contents of va to alter the list of
 *  file attributes returned.
 */
typedef int mpo_vnode_check_getattr_t(
        kauth_cred_t active_cred,
        kauth_cred_t file_cred, /* NULLOK */
        struct vnode *vp,
        struct label *vlabel,
        struct vnode_attr *va
        );
/**
 *  @brief Access control check for retrieving file attributes
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param vlabel Policy label for vp
 *  @param alist List of attributes to retrieve
 *
 *  Determine whether the subject identified by the credential can read
 *  various attributes of the specified vnode, or the filesystem or volume on
 *  which that vnode resides. See <sys/attr.h> for definitions of the
 *  attributes.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege. Access control covers all attributes requested
 *  with this call; the security policy is not permitted to change the set of
 *  attributes requested.
 */
typedef int mpo_vnode_check_getattrlist_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *vlabel,
        struct attrlist *alist
        );
/**
 *  @brief Access control check for retrieving an extended attribute
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param label Policy label for vp
 *  @param name Extended attribute name
 *  @param uio I/O structure pointer
 *
 *  Determine whether the subject identified by the credential can retrieve
 *  the extended attribute from the passed vnode.  The uio parameter
 *  will be NULL when the getxattr(2) call has been made with a NULL data
 *  value; this is done to request the size of the data only.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_getextattr_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label,            /* NULLOK */
        const char *name,
        struct uio *uio                 /* NULLOK */
        );
/**
 *  @brief Access control check for ioctl
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param label Policy label for vp
 *  @param cmd Device-dependent request code; see ioctl(2)
 *
 *  Determine whether the subject identified by the credential can perform
 *  the ioctl operation indicated by com.
 *
 *  @warning Since ioctl data is opaque from the standpoint of the MAC
 *  framework, and since ioctls can affect many aspects of system
 *  operation, policies must exercise extreme care when implementing
 *  access control checks.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_vnode_check_ioctl_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label,
        unsigned int cmd
        );
/**
 *  @brief Access control check for vnode kqfilter
 *  @param active_cred Subject credential
 *  @param kn Object knote
 *  @param vp Object vnode
 *  @param label Policy label for vp
 *
 *  Determine whether the subject identified by the credential can
 *  receive the knote on the passed vnode.
 *
 *  @return Return 0 if access if granted, otherwise an appropriate
 *  value for errno should be returned.
 */
typedef int mpo_vnode_check_kqfilter_t(
        kauth_cred_t active_cred,
        kauth_cred_t file_cred,         /* NULLOK */
        struct knote *kn,
        struct vnode *vp,
        struct label *label
        );
/**
 *  @brief Access control check for relabel
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param vnodelabel Existing policy label for vp
 *  @param newlabel Policy label update to later be applied to vp
 *  @see mpo_relable_vnode_t
 *
 *  Determine whether the subject identified by the credential can relabel
 *  the passed vnode to the passed label update.  If all policies permit
 *  the label change, the actual relabel entry point (mpo_vnode_label_update)
 *  will follow.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_vnode_check_label_update_t(
        struct ucred *cred,
        struct vnode *vp,
        struct label *vnodelabel,
        struct label *newlabel
        );
/**
 *  @brief Access control check for creating link
 *  @param cred Subject credential
 *  @param dvp Directory vnode
 *  @param dlabel Policy label associated with dvp
 *  @param vp Link destination vnode
 *  @param label Policy label associated with vp
 *  @param cnp Component name for the link being created
 *
 *  Determine whether the subject identified by the credential should be
 *  allowed to create a link to the vnode vp with the name specified by cnp.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_vnode_check_link_t(
        kauth_cred_t cred,
        struct vnode *dvp,
        struct label *dlabel,
        struct vnode *vp,
        struct label *label,
        struct componentname *cnp
        );
/**
 *  @brief Access control check for listing extended attributes
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param vlabel Policy label associated with vp
 *
 *  Determine whether the subject identified by the credential can retrieve
 *  a list of named extended attributes from a vnode.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_vnode_check_listextattr_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *vlabel
        );
/**
 *  @brief Access control check for lookup
 *  @param cred Subject credential
 *  @param dvp Directory vnode
 *  @param dlabel Policy label for dvp
 *  @param path Path being looked up
 *  @param pathlen Length of path in bytes
 *
 *  Determine whether the subject identified by the credential can perform
 *  a lookup of the passed path relative to the passed directory vnode.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 *
 *  @note The path may contain untrusted input.  If approved, lookup proceeds
 *  on the path; if a component is found to be a symlink then this hook is
 *  called again with the updated path.
 */
typedef int mpo_vnode_check_lookup_preflight_t(
        kauth_cred_t cred,
        struct vnode *dvp,
        struct label *dlabel,
        const char *path,
        size_t pathlen
        );
/**
 *  @brief Access control check for lookup
 *  @param cred Subject credential
 *  @param dvp Object vnode
 *  @param dlabel Policy label for dvp
 *  @param cnp Component name being looked up
 *
 *  Determine whether the subject identified by the credential can perform
 *  a lookup in the passed directory vnode for the passed name (cnp).
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_lookup_t(
        kauth_cred_t cred,
        struct vnode *dvp,
        struct label *dlabel,
        struct componentname *cnp
        );
/**
 *  @brief Access control check for open
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param label Policy label associated with vp
 *  @param acc_mode open(2) access mode
 *
 *  Determine whether the subject identified by the credential can perform
 *  an open operation on the passed vnode with the passed access mode.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_open_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label,
        int acc_mode
        );
/**
 *  @brief Access control check for read
 *  @param active_cred Subject credential
 *  @param file_cred Credential associated with the struct fileproc
 *  @param vp Object vnode
 *  @param label Policy label for vp
 *
 *  Determine whether the subject identified by the credential can perform
 *  a read operation on the passed vnode.  The active_cred hold the credentials
 *  of the subject performing the operation, and file_cred holds the
 *  credentials of the subject that originally opened the file.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_read_t(
        kauth_cred_t active_cred,       /* SUBJECT */
        kauth_cred_t file_cred, /* NULLOK */
        struct vnode *vp,               /* OBJECT */
        struct label *label             /* LABEL */
        );
/**
 *  @brief Access control check for read directory
 *  @param cred Subject credential
 *  @param dvp Object directory vnode
 *  @param dlabel Policy label for dvp
 *
 *  Determine whether the subject identified by the credential can
 *  perform a readdir operation on the passed directory vnode.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_readdir_t(
        kauth_cred_t cred,              /* SUBJECT */
        struct vnode *dvp,              /* OBJECT */
        struct label *dlabel            /* LABEL */
        );
/**
 *  @brief Access control check for read link
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param label Policy label for vp
 *
 *  Determine whether the subject identified by the credential can perform
 *  a readlink operation on the passed symlink vnode.  This call can be made
 *  in a number of situations, including an explicit readlink call by the
 *  user process, or as a result of an implicit readlink during a name
 *  lookup by the process.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_readlink_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label
        );
/**
 *  @brief Access control check for rename
 *  @param cred Subject credential
 *  @param dvp Directory vnode
 *  @param dlabel Policy label associated with dvp
 *  @param vp vnode to be renamed
 *  @param label Policy label associated with vp
 *  @param cnp Component name for vp
 *  @param tdvp Destination directory vnode
 *  @param tdlabel Policy label associated with tdvp
 *  @param tvp Overwritten vnode
 *  @param tlabel Policy label associated with tvp
 *  @param tcnp Destination component name
 *
 *  Determine whether the subject identified by the credential should be allowed
 *  to rename the vnode vp to something else.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_vnode_check_rename_t(
        kauth_cred_t cred,
        struct vnode *dvp,
        struct label *dlabel,
        struct vnode *vp,
        struct label *label,
        struct componentname *cnp,
        struct vnode *tdvp,
        struct label *tdlabel,
        struct vnode *tvp,
        struct label *tlabel,
        struct componentname *tcnp
        );
/**
 *  @brief Access control check for rename from
 *  @param cred Subject credential
 *  @param dvp Directory vnode
 *  @param dlabel Policy label associated with dvp
 *  @param vp vnode to be renamed
 *  @param label Policy label associated with vp
 *  @param cnp Component name for vp
 *  @see mpo_vnode_check_rename_t
 *  @see mpo_vnode_check_rename_to_t
 *
 *  Determine whether the subject identified by the credential should be
 *  allowed to rename the vnode vp to something else.
 *
 *  Due to VFS locking constraints (to make sure proper vnode locks are
 *  held during this entry point), the vnode relabel checks had to be
 *  split into two parts: relabel_from and relabel to.
 *
 *  This hook is deprecated, mpo_vnode_check_rename_t should be used instead.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_vnode_check_rename_from_t(
        kauth_cred_t cred,
        struct vnode *dvp,
        struct label *dlabel,
        struct vnode *vp,
        struct label *label,
        struct componentname *cnp
        );
/**
 *  @brief Access control check for rename to
 *  @param cred Subject credential
 *  @param dvp Directory vnode
 *  @param dlabel Policy label associated with dvp
 *  @param vp Overwritten vnode
 *  @param label Policy label associated with vp
 *  @param samedir Boolean; 1 if the source and destination directories are the same
 *  @param cnp Destination component name
 *  @see mpo_vnode_check_rename_t
 *  @see mpo_vnode_check_rename_from_t
 *
 *  Determine whether the subject identified by the credential should be
 *  allowed to rename to the vnode vp, into the directory dvp, or to the
 *  name represented by cnp. If there is no existing file to overwrite,
 *  vp and label will be NULL.
 *
 *  Due to VFS locking constraints (to make sure proper vnode locks are
 *  held during this entry point), the vnode relabel checks had to be
 *  split into two parts: relabel_from and relabel to.
 *
 *  This hook is deprecated, mpo_vnode_check_rename_t should be used instead.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_vnode_check_rename_to_t(
        kauth_cred_t cred,
        struct vnode *dvp,
        struct label *dlabel,
        struct vnode *vp,                       /* NULLOK */
        struct label *label,                    /* NULLOK */
        int samedir,
        struct componentname *cnp
        );
/**
 *  @brief Access control check for revoke
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param label Policy label for vp
 *
 *  Determine whether the subject identified by the credential can revoke
 *  access to the passed vnode.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_revoke_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label
        );
/**
 *  @brief Access control check for searchfs
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param vlabel Policy label for vp
 *  @param alist List of attributes used as search criteria
 *
 *  Determine whether the subject identified by the credential can search the
 *  vnode using the searchfs system call.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_vnode_check_searchfs_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *vlabel,
        struct attrlist *alist
        );
/**
 *  @brief Access control check for select
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param label Policy label for vp
 *  @param which The operation selected on: FREAD or FWRITE
 *
 *  Determine whether the subject identified by the credential can select
 *  the vnode.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_vnode_check_select_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label,
        int which
        );
/**
 *  @brief Access control check for setting ACL
 *  @param cred Subject credential
 *  @param vp Object node
 *  @param label Policy label for vp
 *  @param acl ACL structure pointer
 *
 *  Determine whether the subject identified by the credential can set an ACL
 *  on the specified vnode.  The ACL pointer will be NULL when removing an ACL.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_setacl_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label,
        struct kauth_acl *acl
        );
/**
 *  @brief Access control check for setting file attributes
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param vlabel Policy label for vp
 *  @param alist List of attributes to set
 *
 *  Determine whether the subject identified by the credential can set
 *  various attributes of the specified vnode, or the filesystem or volume on
 *  which that vnode resides. See <sys/attr.h> for definitions of the
 *  attributes.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege. Access control covers all attributes requested
 *  with this call.
 */
typedef int mpo_vnode_check_setattrlist_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *vlabel,
        struct attrlist *alist
        );
/**
 *  @brief Access control check for setting extended attribute
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param label Policy label for vp
 *  @param name Extended attribute name
 *  @param uio I/O structure pointer
 *
 *  Determine whether the subject identified by the credential can set the
 *  extended attribute of passed name and passed namespace on the passed
 *  vnode. Policies implementing security labels backed into extended
 *  attributes may want to provide additional protections for those
 *  attributes. Additionally, policies should avoid making decisions based
 *  on the data referenced from uio, as there is a potential race condition
 *  between this check and the actual operation. The uio may also be NULL
 *  if a delete operation is being performed.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_setextattr_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label,
        const char *name,
        struct uio *uio
        );
/**
 *  @brief Access control check for setting flags
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param label Policy label for vp
 *  @param flags File flags; see chflags(2)
 *
 *  Determine whether the subject identified by the credential can set
 *  the passed flags on the passed vnode.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_setflags_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label,
        u_long flags
        );
/**
 *  @brief Access control check for setting mode
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param label Policy label for vp
 *  @param mode File mode; see chmod(2)
 *
 *  Determine whether the subject identified by the credential can set
 *  the passed mode on the passed vnode.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_setmode_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label,
        mode_t mode
        );
/**
 *  @brief Access control check for setting uid and gid
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param label Policy label for vp
 *  @param uid User ID
 *  @param gid Group ID
 *
 *  Determine whether the subject identified by the credential can set
 *  the passed uid and passed gid as file uid and file gid on the passed
 *  vnode. The IDs may be set to (-1) to request no update.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_setowner_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label,
        uid_t uid,
        gid_t gid
        );
/**
 *  @brief Access control check for setting timestamps
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param label Policy label for vp
 *  @param atime Access time; see utimes(2)
 *  @param mtime Modification time; see utimes(2)
 *
 *  Determine whether the subject identified by the credential can set
 *  the passed access timestamps on the passed vnode.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_setutimes_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label,
        struct timespec atime,
        struct timespec mtime
        );
/**
 *  @brief Access control check after determining the code directory hash
 *  @param vp vnode vnode to combine into proc
 *  @param label label associated with the vnode
 *  @param cpu_type cpu type of the signature being checked
 *  @param cs_blob the code signature to check
 *  @param cs_flags update code signing flags if needed
 *  @param signer_type output parameter for the code signature's signer type
 *  @param flags operational flag to mpo_vnode_check_signature
 *  @param fatal_failure_desc description of fatal failure
 *  @param fatal_failure_desc_len failure description len, failure is fatal if non-0
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.
 */
typedef int mpo_vnode_check_signature_t(
        struct vnode *vp,
        struct label *label,
        cpu_type_t cpu_type,
        struct cs_blob *cs_blob,
        unsigned int *cs_flags,
        unsigned int *signer_type,
        int flags,
        char **fatal_failure_desc, size_t *fatal_failure_desc_len
        );
/**
 *  @brief Access control check for stat
 *  @param active_cred Subject credential
 *  @param file_cred Credential associated with the struct fileproc
 *  @param vp Object vnode
 *  @param label Policy label for vp
 *
 *  Determine whether the subject identified by the credential can stat
 *  the passed vnode. See stat(2) for more information.  The active_cred
 *  hold the credentials of the subject performing the operation, and
 *  file_cred holds the credentials of the subject that originally
 *  opened the file.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_stat_t(
        struct ucred *active_cred,
        struct ucred *file_cred,        /* NULLOK */
        struct vnode *vp,
        struct label *label
        );
/**
 *  @brief Access control check for vnode trigger resolution
 *  @param cred Subject credential
 *  @param dvp Object vnode
 *  @param dlabel Policy label for dvp
 *  @param cnp Component name that triggered resolution
 *
 *  Determine whether the subject identified by the credential can trigger
 *  resolution of the passed name (cnp) in the passed directory vnode
 *  via an external trigger resolver.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_trigger_resolve_t(
        kauth_cred_t cred,
        struct vnode *dvp,
        struct label *dlabel,
        struct componentname *cnp
        );
/**
 *  @brief Access control check for truncate/ftruncate
 *  @param active_cred Subject credential
 *  @param file_cred Credential associated with the struct fileproc
 *  @param vp Object vnode
 *  @param label Policy label for vp
 *
 *  Determine whether the subject identified by the credential can
 *  perform a truncate operation on the passed vnode.  The active_cred hold
 *  the credentials of the subject performing the operation, and
 *  file_cred holds the credentials of the subject that originally
 *  opened the file.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_truncate_t(
        kauth_cred_t active_cred,
        kauth_cred_t file_cred, /* NULLOK */
        struct vnode *vp,
        struct label *label
        );
/**
 *  @brief Access control check for binding UNIX domain socket
 *  @param cred Subject credential
 *  @param dvp Directory vnode
 *  @param dlabel Policy label for dvp
 *  @param cnp Component name for dvp
 *  @param vap vnode attributes for vap
 *
 *  Determine whether the subject identified by the credential can perform a
 *  bind operation on a UNIX domain socket with the passed parent directory,
 *  passed name information, and passed attribute information.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_uipc_bind_t(
        kauth_cred_t cred,
        struct vnode *dvp,
        struct label *dlabel,
        struct componentname *cnp,
        struct vnode_attr *vap
        );
/**
 *  @brief Access control check for connecting UNIX domain socket
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param label Policy label associated with vp
 *  @param so Socket
 *
 *  Determine whether the subject identified by the credential can perform a
 *  connect operation on the passed UNIX domain socket vnode.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_uipc_connect_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label,
        socket_t so
        );
/**
 *  @brief Access control check for deleting vnode
 *  @param cred Subject credential
 *  @param dvp Parent directory vnode
 *  @param dlabel Policy label for dvp
 *  @param vp Object vnode to delete
 *  @param label Policy label for vp
 *  @param cnp Component name for vp
 *  @see mpo_check_rename_to_t
 *
 *  Determine whether the subject identified by the credential can delete
 *  a vnode from the passed parent directory and passed name information.
 *  This call may be made in a number of situations, including as a
 *  results of calls to unlink(2) and rmdir(2). Policies implementing
 *  this entry point should also implement mpo_check_rename_to to
 *  authorize deletion of objects as a result of being the target of a rename.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_unlink_t(
        kauth_cred_t cred,
        struct vnode *dvp,
        struct label *dlabel,
        struct vnode *vp,
        struct label *label,
        struct componentname *cnp
        );
/**
 *  @brief Access control check for write
 *  @param active_cred Subject credential
 *  @param file_cred Credential associated with the struct fileproc
 *  @param vp Object vnode
 *  @param label Policy label for vp
 *
 *  Determine whether the subject identified by the credential can
 *  perform a write operation on the passed vnode.  The active_cred hold
 *  the credentials of the subject performing the operation, and
 *  file_cred holds the credentials of the subject that originally
 *  opened the file.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EACCES for label mismatch or
 *  EPERM for lack of privilege.
 */
typedef int mpo_vnode_check_write_t(
        kauth_cred_t active_cred,
        kauth_cred_t file_cred, /* NULLOK */
        struct vnode *vp,
        struct label *label
        );
/**
 *  @brief Associate a vnode with a devfs entry
 *  @param mp Devfs mount point
 *  @param mntlabel Devfs mount point label
 *  @param de Devfs directory entry
 *  @param delabel Label associated with de
 *  @param vp vnode associated with de
 *  @param vlabel Label associated with vp
 *
 *  Fill in the label (vlabel) for a newly created devfs vnode.  The
 *  label is typically derived from the label on the devfs directory
 *  entry or the label on the filesystem, supplied as parameters.
 */
typedef void mpo_vnode_label_associate_devfs_t(
        struct mount *mp,
        struct label *mntlabel,
        struct devnode *de,
        struct label *delabel,
        struct vnode *vp,
        struct label *vlabel
        );
/**
 *  @brief Associate a label with a vnode
 *  @param mp File system mount point
 *  @param mntlabel File system mount point label
 *  @param vp Vnode to label
 *  @param vlabel Label associated with vp
 *
 *  Attempt to retrieve label information for the vnode, vp, from the
 *  file system extended attribute store.  The label should be stored in
 *  the supplied vlabel parameter.  If a policy cannot retrieve an
 *  extended attribute, sometimes it is acceptible to fallback to using
 *  the mntlabel.
 *
 *  If the policy requires vnodes to have a valid label elsewhere it
 *  MUST NOT return other than temporary errors, and must always provide
 *  a valid label of some sort.  Returning an error will cause vnode
 *  labeling to be retried at a later access.  Failure to handle policy
 *  centric errors internally (corrupt labels etc.) will result in
 *  inaccessible files.
 *
 *  @return In the event of an error, an appropriate value for errno
 *  should be returned, otherwise return 0 upon success.
 */
typedef int mpo_vnode_label_associate_extattr_t(
        struct mount *mp,
        struct label *mntlabel,
        struct vnode *vp,
        struct label *vlabel
        );
/**
 *  @brief Associate a file label with a vnode
 *  @param cred User credential
 *  @param mp Fdesc mount point
 *  @param mntlabel Fdesc mount point label
 *  @param fg Fileglob structure
 *  @param label Policy label for fg
 *  @param vp Vnode to label
 *  @param vlabel Label associated with vp
 *
 *  Associate label information for the vnode, vp, with the label of
 *  the open file descriptor described by fg.
 *  The label should be stored in the supplied vlabel parameter.
 */
typedef void mpo_vnode_label_associate_file_t(
        struct ucred *cred,
        struct mount *mp,
        struct label *mntlabel,
        struct fileglob *fg,
        struct label *label,
        struct vnode *vp,
        struct label *vlabel
        );
/**
 *  @brief Associate a pipe label with a vnode
 *  @param cred User credential for the process that opened the pipe
 *  @param cpipe Pipe structure
 *  @param pipelabel Label associated with pipe
 *  @param vp Vnode to label
 *  @param vlabel Label associated with vp
 *
 *  Associate label information for the vnode, vp, with the label of
 *  the pipe described by the pipe structure cpipe.
 *  The label should be stored in the supplied vlabel parameter.
 */
typedef void mpo_vnode_label_associate_pipe_t(
        struct ucred *cred,
        struct pipe *cpipe,
        struct label *pipelabel,
        struct vnode *vp,
        struct label *vlabel
        );
/**
 *  @brief Associate a POSIX semaphore label with a vnode
 *  @param cred User credential for the process that create psem
 *  @param psem POSIX semaphore structure
 *  @param psemlabel Label associated with psem
 *  @param vp Vnode to label
 *  @param vlabel Label associated with vp
 *
 *  Associate label information for the vnode, vp, with the label of
 *  the POSIX semaphore described by psem.
 *  The label should be stored in the supplied vlabel parameter.
 */
typedef void mpo_vnode_label_associate_posixsem_t(
        struct ucred *cred,
        struct pseminfo *psem,
        struct label *psemlabel,
        struct vnode *vp,
        struct label *vlabel
        );
/**
 *  @brief Associate a POSIX shared memory label with a vnode
 *  @param cred User credential for the process that created pshm
 *  @param pshm POSIX shared memory structure
 *  @param pshmlabel Label associated with pshm
 *  @param vp Vnode to label
 *  @param vlabel Label associated with vp
 *
 *  Associate label information for the vnode, vp, with the label of
 *  the POSIX shared memory region described by pshm.
 *  The label should be stored in the supplied vlabel parameter.
 */
typedef void mpo_vnode_label_associate_posixshm_t(
        struct ucred *cred,
        struct pshminfo *pshm,
        struct label *pshmlabel,
        struct vnode *vp,
        struct label *vlabel
        );
/**
 *  @brief Associate a label with a vnode
 *  @param mp File system mount point
 *  @param mntlabel File system mount point label
 *  @param vp Vnode to label
 *  @param vlabel Label associated with vp
 *
 *  On non-multilabel file systems, set the label for a vnode.  The
 *  label will most likely be based on the file system label.
 */
typedef void mpo_vnode_label_associate_singlelabel_t(
        struct mount *mp,
        struct label *mntlabel,
        struct vnode *vp,
        struct label *vlabel
        );
/**
 *  @brief Associate a socket label with a vnode
 *  @param cred User credential for the process that opened the socket
 *  @param so Socket structure
 *  @param solabel Label associated with so
 *  @param vp Vnode to label
 *  @param vlabel Label associated with vp
 *
 *  Associate label information for the vnode, vp, with the label of
 *  the open socket described by the socket structure so.
 *  The label should be stored in the supplied vlabel parameter.
 */
typedef void mpo_vnode_label_associate_socket_t(
        kauth_cred_t cred,
        socket_t so,
        struct label *solabel,
        struct vnode *vp,
        struct label *vlabel
        );
/**
 *  @brief Copy a vnode label
 *  @param src Source vnode label
 *  @param dest Destination vnode label
 *
 *  Copy the vnode label information from src to dest.  On Darwin, this
 *  is currently only necessary when executing interpreted scripts, but
 *  will later be used if vnode label externalization cannot be an
 *  atomic operation.
 */
typedef void mpo_vnode_label_copy_t(
        struct label *src,
        struct label *dest
        );
/**
 *  @brief Destroy vnode label
 *  @param label The label to be destroyed
 *
 *  Destroy a vnode label.  Since the object is going out of scope,
 *  policy modules should free any internal storage associated with the
 *  label so that it may be destroyed.
 */
typedef void mpo_vnode_label_destroy_t(
        struct label *label
        );
/**
 *  @brief Externalize a vnode label for auditing
 *  @param label Label to be externalized
 *  @param element_name Name of the label namespace for which labels should be
 *  externalized
 *  @param sb String buffer to be filled with a text representation of the label
 *
 *  Produce an external representation of the label on a vnode suitable for
 *  inclusion in an audit record.  An externalized label consists of a text
 *  representation of the label contents that will be added to the audit record
 *  as part of a text token.  Policy-agnostic user space tools will display
 *  this externalized version.
 *
 *  @return 0 on success, return non-zero if an error occurs while
 *  externalizing the label data.
 *
 */
typedef int mpo_vnode_label_externalize_audit_t(
        struct label *label,
        char *element_name,
        struct sbuf *sb
        );
/**
 *  @brief Externalize a vnode label
 *  @param label Label to be externalized
 *  @param element_name Name of the label namespace for which labels should be
 *  externalized
 *  @param sb String buffer to be filled with a text representation of the label
 *
 *  Produce an external representation of the label on a vnode.  An
 *  externalized label consists of a text representation of the label
 *  contents that can be used with user applications.  Policy-agnostic
 *  user space tools will display this externalized version.
 *
 *  @return 0 on success, return non-zero if an error occurs while
 *  externalizing the label data.
 *
 */
typedef int mpo_vnode_label_externalize_t(
        struct label *label,
        char *element_name,
        struct sbuf *sb
        );
/**
 *  @brief Initialize vnode label
 *  @param label New label to initialize
 *
 *  Initialize label storage for use with a newly instantiated vnode, or
 *  for temporary storage associated with the copying in or out of a
 *  vnode label.  While it is necessary to allocate space for a
 *  kernel-resident vnode label, it is not yet necessary to link this vnode
 *  with persistent label storage facilities, such as extended attributes.
 *  Sleeping is permitted.
 */
typedef void mpo_vnode_label_init_t(
        struct label *label
        );
/**
 *  @brief Internalize a vnode label
 *  @param label Label to be internalized
 *  @param element_name Name of the label namespace for which the label should
 *  be internalized
 *  @param element_data Text data to be internalized
 *
 *  Produce a vnode label from an external representation.  An
 *  externalized label consists of a text representation of the label
 *  contents that can be used with user applications.  Policy-agnostic
 *  user space tools will forward text version to the kernel for
 *  processing by individual policy modules.
 *
 *  The policy's internalize entry points will be called only if the
 *  policy has registered interest in the label namespace.
 *
 *  @return 0 on success, Otherwise, return non-zero if an error occurs
 *  while internalizing the label data.
 */
typedef int mpo_vnode_label_internalize_t(
        struct label *label,
        char *element_name,
        char *element_data
        );
/**
 *  @brief Clean up a vnode label
 *  @param label The label to be cleaned for re-use
 *
 *  Clean up a vnode label.  Darwin (Tiger, 8.x) allocates vnodes on demand, but
 *  typically never frees them.  Before vnodes are placed back on free lists for
 *  re-use, policies can cleanup or overwrite any information present in the label.
 */
typedef void mpo_vnode_label_recycle_t(
        struct label *label
        );
/**
 *  @brief Write a label to a extended attribute
 *  @param cred Subject credential
 *  @param vp The vnode for which the label is being stored
 *  @param vlabel Label associated with vp
 *  @param intlabel The new label to store
 *
 *  Store a new label in the extended attribute corresponding to the
 *  supplied vnode.  The policy has already authorized the operation;
 *  this call must be implemented in order to perform the actual
 *  operation.
 *
 *  @return In the event of an error, an appropriate value for errno
 *  should be returned, otherwise return 0 upon success.
 *
 *  @warning XXX After examining the extended attribute implementation on
 *  Apple's future release, this entry point may be changed.
 */
typedef int mpo_vnode_label_store_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *vlabel,
        struct label *intlabel
        );
/**
 *  @brief Update vnode label from extended attributes
 *  @param mp File system mount point
 *  @param mntlabel Mount point label
 *  @param vp Vnode to label
 *  @param vlabel Label associated with vp
 *  @param name Name of the xattr
 *  @see mpo_vnode_check_setextattr_t
 *
 *  When an extended attribute is updated via the Vendor attribute management
 *  functions, the MAC vnode label might also require an update.
 *  Policies should first determine if 'name' matches their xattr label
 *  name.  If it does, the kernel is has either replaced or removed the
 *  named extended attribute that was previously associated with the
 *  vnode.  Normally labels should only be modified via MAC Framework label
 *  management calls, but sometimes the user space components will directly
 *  modify extended attributes.  For example, 'cp', 'tar', etc. manage
 *  extended attributes in userspace, not the kernel.
 *
 *  This entry point is called after the label update has occurred, so
 *  it cannot return a failure.  However, the operation is preceded by
 *  the mpo_vnode_check_setextattr() access control check.
 *
 *  If the vnode label needs to be updated the policy should return
 *  a non-zero value.  The vnode label will be marked for re-association
 *  by the framework.
 */
typedef int mpo_vnode_label_update_extattr_t(
        struct mount *mp,
        struct label *mntlabel,
        struct vnode *vp,
        struct label *vlabel,
        const char *name
        );
/**
 *  @brief Update a vnode label
 *  @param cred Subject credential
 *  @param vp The vnode to relabel
 *  @param vnodelabel Existing vnode label
 *  @param label New label to replace existing label
 *  @see mpo_vnode_check_label_update_t
 *
 *  The subject identified by the credential has previously requested
 *  and was authorized to relabel the vnode; this entry point allows
 *  policies to perform the actual relabel operation.  Policies should
 *  update vnodelabel using the label stored in the label parameter.
 */
typedef void mpo_vnode_label_update_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *vnodelabel,
        struct label *label
        );
/**
 *  @brief Find deatched signatures for a shared library
 *  @param p file trying to find the signature
 *  @param vp The vnode to relabel
 *  @param offset offset in the macho that the signature is requested for (for fat binaries)
 *  @param label Existing vnode label
 *
 */
typedef int mpo_vnode_find_sigs_t(
        struct proc *p,
        struct vnode *vp,
        off_t offset,
        struct label *label
        );
/**
 *  @brief Create a new vnode, backed by extended attributes
 *  @param cred User credential for the creating process
 *  @param mp File system mount point
 *  @param mntlabel File system mount point label
 *  @param dvp Parent directory vnode
 *  @param dlabel Parent directory vnode label
 *  @param vp Newly created vnode
 *  @param vlabel Label to associate with the new vnode
 *  @param cnp Component name for vp
 *
 *  Write out the label for the newly created vnode, most likely storing
 *  the results in a file system extended attribute.  Most policies will
 *  derive the new vnode label using information from a combination
 *  of the subject (user) credential, the file system label, the parent
 *  directory label, and potentially the path name component.
 *
 *  @return If the operation succeeds, store the new label in vlabel and
 *  return 0.  Otherwise, return an appropriate errno value.
 */
typedef int mpo_vnode_notify_create_t(
        kauth_cred_t cred,
        struct mount *mp,
        struct label *mntlabel,
        struct vnode *dvp,
        struct label *dlabel,
        struct vnode *vp,
        struct label *vlabel,
        struct componentname *cnp
        );

/**
 *  @brief Inform MAC policies that a vnode has been opened
 *  @param cred User credential for the creating process
 *  @param vp vnode opened
 *  @param label Policy label for the vp
 *  @param acc_mode open(2) access mode used
 *
 *  Inform Mac policies that a vnode have been successfully opened
 *  (passing all MAC polices and DAC).
 */
typedef void mpo_vnode_notify_open_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label,
        int acc_mode
        );

/**
 *  @brief Inform MAC policies that a vnode has been renamed
 *  @param cred User credential for the renaming process
 *  @param vp Vnode that's being renamed
 *  @param label Policy label for vp
 *  @param dvp Parent directory for the destination
 *  @param dlabel Policy label for dvp
 *  @param cnp Component name for the destination
 *
 *  Inform MAC policies that a vnode has been renamed.
 */
typedef void mpo_vnode_notify_rename_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label,
        struct vnode *dvp,
        struct label *dlabel,
        struct componentname *cnp
        );

/**
 *  @brief Inform MAC policies that a vnode has been linked
 *  @param cred User credential for the renaming process
 *  @param dvp Parent directory for the destination
 *  @param dlabel Policy label for dvp
 *  @param vp Vnode that's being linked
 *  @param vlabel Policy label for vp
 *  @param cnp Component name for the destination
 *
 *  Inform MAC policies that a vnode has been linked.
 */
typedef void mpo_vnode_notify_link_t(
        kauth_cred_t cred,
        struct vnode *dvp,
        struct label *dlabel,
        struct vnode *vp,
        struct label *vlabel,
        struct componentname *cnp
        );

/**
 *  @brief Inform MAC policies that an extended attribute has been removed from a vnode
 *  @param cred Subject credential
 *  @param vp Object node
 *  @param label Policy label for vp
 *  @param name Extended attribute name
 *
 *  Inform MAC policies that an extended attribute has been removed from a vnode.
 */
typedef void mpo_vnode_notify_deleteextattr_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label,
        const char *name
        );


/**
 *  @brief Inform MAC policies that an ACL has been set on a vnode
 *  @param cred Subject credential
 *  @param vp Object node
 *  @param label Policy label for vp
 *  @param acl ACL structure pointer
 *
 *  Inform MAC policies that an ACL has been set on a vnode.
 */
typedef void mpo_vnode_notify_setacl_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label,
        struct kauth_acl *acl
        );

/**
 *  @brief Inform MAC policies that an attributes have been set on a vnode
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param label Policy label for vp
 *  @param alist List of attributes to set
 *
 *  Inform MAC policies that an attributes have been set on a vnode.
 */
typedef void mpo_vnode_notify_setattrlist_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label,
        struct attrlist *alist
        );

/**
 *  @brief Inform MAC policies that an extended attribute has been set on a vnode
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param label Policy label for vp
 *  @param name Extended attribute name
 *  @param uio I/O structure pointer
 *
 *  Inform MAC policies that an extended attribute has been set on a vnode.
 */
typedef void mpo_vnode_notify_setextattr_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label,
        const char *name,
        struct uio *uio
        );

/**
 *  @brief Inform MAC policies that flags have been set on a vnode
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param label Policy label for vp
 *  @param flags File flags; see chflags(2)
 *
 *  Inform MAC policies that flags have been set on a vnode.
 */
typedef void mpo_vnode_notify_setflags_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label,
        u_long flags
        );

/**
 *  @brief Inform MAC policies that a new mode has been set on a vnode
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param label Policy label for vp
 *  @param mode File mode; see chmod(2)
 *
 *  Inform MAC policies that a new mode has been set on a vnode.
 */
typedef void mpo_vnode_notify_setmode_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label,
        mode_t mode
        );

/**
 *  @brief Inform MAC policies that new uid/gid have been set on a vnode
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param label Policy label for vp
 *  @param uid User ID
 *  @param gid Group ID
 *
 *  Inform MAC policies that new uid/gid have been set on a vnode.
 */
typedef void mpo_vnode_notify_setowner_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label,
        uid_t uid,
        gid_t gid
        );

/**
 *  @brief Inform MAC policies that new timestamps have been set on a vnode
 *  @param cred Subject credential
 *  @param vp Object vnode
 *  @param label Policy label for vp
 *  @param atime Access time; see utimes(2)
 *  @param mtime Modification time; see utimes(2)
 *
 *  Inform MAC policies that new timestamps have been set on a vnode.
 */
typedef void mpo_vnode_notify_setutimes_t(
        kauth_cred_t cred,
        struct vnode *vp,
        struct label *label,
        struct timespec atime,
        struct timespec mtime
        );

/**
 *  @brief Inform MAC policies that a vnode has been truncated
 *  @param cred Subject credential
 *  @param file_cred Credential associated with the struct fileproc
 *  @param vp Object vnode
 *  @param label Policy label for vp
 *
 *  Inform MAC policies that a vnode has been truncated.
 */
typedef void mpo_vnode_notify_truncate_t(
        kauth_cred_t cred,
        kauth_cred_t file_cred,
        struct vnode *vp,
        struct label *label
        );


/**
 *  @brief Inform MAC policies that a pty slave has been granted
 *  @param p Responsible process
 *  @param tp tty data structure
 *  @param dev Major and minor numbers of device
 *  @param label Policy label for tp
 *
 *  Inform MAC policies that a pty slave has been granted.
 */
typedef void mpo_pty_notify_grant_t(
        proc_t p,
        struct tty *tp,
        dev_t dev,
        struct label *label
        );

/**
 *  @brief Inform MAC policies that a pty master has been closed
 *  @param p Responsible process
 *  @param tp tty data structure
 *  @param dev Major and minor numbers of device
 *  @param label Policy label for tp
 *
 *  Inform MAC policies that a pty master has been closed.
 */
typedef void mpo_pty_notify_close_t(
        proc_t p,
        struct tty *tp,
        dev_t dev,
        struct label *label
        );

/**
 *  @brief Access control check for kext loading
 *  @param cred Subject credential
 *  @param identifier Kext identifier
 *
 *  Determine whether the subject identified by the credential can load the
 *  specified kext.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EPERM for lack of privilege.
 */
typedef int mpo_kext_check_load_t(
        kauth_cred_t cred,
        const char *identifier
        );

/**
 *  @brief Access control check for kext unloading
 *  @param cred Subject credential
 *  @param identifier Kext identifier
 *
 *  Determine whether the subject identified by the credential can unload the
 *  specified kext.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned. Suggested failure: EPERM for lack of privilege.
 */
typedef int mpo_kext_check_unload_t(
        kauth_cred_t cred,
        const char *identifier
        );

/**
 *  @brief Access control check for querying information about loaded kexts
 *  @param cred Subject credential
 *
 *  Determine whether the subject identified by the credential can query
 *  information about loaded kexts.
 *
 *  @return Return 0 if access is granted, otherwise an appropriate value for
 *  errno should be returned.  Suggested failure: EPERM for lack of privilege.
 */
typedef int mpo_kext_check_query_t(
        kauth_cred_t cred
        );

/*
 * Placeholder for future events that may need mac hooks.
 */
typedef void mpo_reserved_hook_t(void);

/*
 * Policy module operations.
 *
 * Please note that this should be kept in sync with the check assumptions
 * policy in bsd/kern/policy_check.c (policy_ops struct).
 */
#define MAC_POLICY_OPS_VERSION 55 /* inc when new reserved slots are taken */
struct mac_policy_ops {
        mpo_audit_check_postselect_t            *mpo_audit_check_postselect;
        mpo_audit_check_preselect_t             *mpo_audit_check_preselect;

        mpo_bpfdesc_label_associate_t           *mpo_bpfdesc_label_associate;
        mpo_bpfdesc_label_destroy_t             *mpo_bpfdesc_label_destroy;
        mpo_bpfdesc_label_init_t                *mpo_bpfdesc_label_init;
        mpo_bpfdesc_check_receive_t             *mpo_bpfdesc_check_receive;

        mpo_cred_check_label_update_execve_t    *mpo_cred_check_label_update_execve;
        mpo_cred_check_label_update_t           *mpo_cred_check_label_update;
        mpo_cred_check_visible_t                *mpo_cred_check_visible;
        mpo_cred_label_associate_fork_t         *mpo_cred_label_associate_fork;
        mpo_cred_label_associate_kernel_t       *mpo_cred_label_associate_kernel;
        mpo_cred_label_associate_t              *mpo_cred_label_associate;
        mpo_cred_label_associate_user_t         *mpo_cred_label_associate_user;
        mpo_cred_label_destroy_t                *mpo_cred_label_destroy;
        mpo_cred_label_externalize_audit_t      *mpo_cred_label_externalize_audit;
        mpo_cred_label_externalize_t            *mpo_cred_label_externalize;
        mpo_cred_label_init_t                   *mpo_cred_label_init;
        mpo_cred_label_internalize_t            *mpo_cred_label_internalize;
        mpo_cred_label_update_execve_t          *mpo_cred_label_update_execve;
        mpo_cred_label_update_t                 *mpo_cred_label_update;

        mpo_devfs_label_associate_device_t      *mpo_devfs_label_associate_device;
        mpo_devfs_label_associate_directory_t   *mpo_devfs_label_associate_directory;
        mpo_devfs_label_copy_t                  *mpo_devfs_label_copy;
        mpo_devfs_label_destroy_t               *mpo_devfs_label_destroy;
        mpo_devfs_label_init_t                  *mpo_devfs_label_init;
        mpo_devfs_label_update_t                *mpo_devfs_label_update;

        mpo_file_check_change_offset_t          *mpo_file_check_change_offset;
        mpo_file_check_create_t                 *mpo_file_check_create;
        mpo_file_check_dup_t                    *mpo_file_check_dup;
        mpo_file_check_fcntl_t                  *mpo_file_check_fcntl;
        mpo_file_check_get_offset_t             *mpo_file_check_get_offset;
        mpo_file_check_get_t                    *mpo_file_check_get;
        mpo_file_check_inherit_t                *mpo_file_check_inherit;
        mpo_file_check_ioctl_t                  *mpo_file_check_ioctl;
        mpo_file_check_lock_t                   *mpo_file_check_lock;
        mpo_file_check_mmap_downgrade_t         *mpo_file_check_mmap_downgrade;
        mpo_file_check_mmap_t                   *mpo_file_check_mmap;
        mpo_file_check_receive_t                *mpo_file_check_receive;
        mpo_file_check_set_t                    *mpo_file_check_set;
        mpo_file_label_init_t                   *mpo_file_label_init;
        mpo_file_label_destroy_t                *mpo_file_label_destroy;
        mpo_file_label_associate_t              *mpo_file_label_associate;

        mpo_ifnet_check_label_update_t          *mpo_ifnet_check_label_update;
        mpo_ifnet_check_transmit_t              *mpo_ifnet_check_transmit;
        mpo_ifnet_label_associate_t             *mpo_ifnet_label_associate;
        mpo_ifnet_label_copy_t                  *mpo_ifnet_label_copy;
        mpo_ifnet_label_destroy_t               *mpo_ifnet_label_destroy;
        mpo_ifnet_label_externalize_t           *mpo_ifnet_label_externalize;
        mpo_ifnet_label_init_t                  *mpo_ifnet_label_init;
        mpo_ifnet_label_internalize_t           *mpo_ifnet_label_internalize;
        mpo_ifnet_label_update_t                *mpo_ifnet_label_update;
        mpo_ifnet_label_recycle_t               *mpo_ifnet_label_recycle;

        mpo_inpcb_check_deliver_t               *mpo_inpcb_check_deliver;
        mpo_inpcb_label_associate_t             *mpo_inpcb_label_associate;
        mpo_inpcb_label_destroy_t               *mpo_inpcb_label_destroy;
        mpo_inpcb_label_init_t                  *mpo_inpcb_label_init;
        mpo_inpcb_label_recycle_t               *mpo_inpcb_label_recycle;
        mpo_inpcb_label_update_t                *mpo_inpcb_label_update;

        mpo_iokit_check_device_t                *mpo_iokit_check_device;

        mpo_ipq_label_associate_t               *mpo_ipq_label_associate;
        mpo_ipq_label_compare_t                 *mpo_ipq_label_compare;
        mpo_ipq_label_destroy_t                 *mpo_ipq_label_destroy;
        mpo_ipq_label_init_t                    *mpo_ipq_label_init;
        mpo_ipq_label_update_t                  *mpo_ipq_label_update;

        mpo_file_check_library_validation_t     *mpo_file_check_library_validation;
        mpo_vnode_notify_setacl_t               *mpo_vnode_notify_setacl;
        mpo_vnode_notify_setattrlist_t          *mpo_vnode_notify_setattrlist;
        mpo_vnode_notify_setextattr_t           *mpo_vnode_notify_setextattr;
        mpo_vnode_notify_setflags_t             *mpo_vnode_notify_setflags;
        mpo_vnode_notify_setmode_t              *mpo_vnode_notify_setmode;
        mpo_vnode_notify_setowner_t             *mpo_vnode_notify_setowner;
        mpo_vnode_notify_setutimes_t            *mpo_vnode_notify_setutimes;
        mpo_vnode_notify_truncate_t             *mpo_vnode_notify_truncate;

        mpo_mbuf_label_associate_bpfdesc_t      *mpo_mbuf_label_associate_bpfdesc;
        mpo_mbuf_label_associate_ifnet_t        *mpo_mbuf_label_associate_ifnet;
        mpo_mbuf_label_associate_inpcb_t        *mpo_mbuf_label_associate_inpcb;
        mpo_mbuf_label_associate_ipq_t          *mpo_mbuf_label_associate_ipq;
        mpo_mbuf_label_associate_linklayer_t    *mpo_mbuf_label_associate_linklayer;
        mpo_mbuf_label_associate_multicast_encap_t *mpo_mbuf_label_associate_multicast_encap;
        mpo_mbuf_label_associate_netlayer_t     *mpo_mbuf_label_associate_netlayer;
        mpo_mbuf_label_associate_socket_t       *mpo_mbuf_label_associate_socket;
        mpo_mbuf_label_copy_t                   *mpo_mbuf_label_copy;
        mpo_mbuf_label_destroy_t                *mpo_mbuf_label_destroy;
        mpo_mbuf_label_init_t                   *mpo_mbuf_label_init;

        mpo_mount_check_fsctl_t                 *mpo_mount_check_fsctl;
        mpo_mount_check_getattr_t               *mpo_mount_check_getattr;
        mpo_mount_check_label_update_t          *mpo_mount_check_label_update;
        mpo_mount_check_mount_t                 *mpo_mount_check_mount;
        mpo_mount_check_remount_t               *mpo_mount_check_remount;
        mpo_mount_check_setattr_t               *mpo_mount_check_setattr;
        mpo_mount_check_stat_t                  *mpo_mount_check_stat;
        mpo_mount_check_umount_t                *mpo_mount_check_umount;
        mpo_mount_label_associate_t             *mpo_mount_label_associate;
        mpo_mount_label_destroy_t               *mpo_mount_label_destroy;
        mpo_mount_label_externalize_t           *mpo_mount_label_externalize;
        mpo_mount_label_init_t                  *mpo_mount_label_init;
        mpo_mount_label_internalize_t           *mpo_mount_label_internalize;

        mpo_netinet_fragment_t                  *mpo_netinet_fragment;
        mpo_netinet_icmp_reply_t                *mpo_netinet_icmp_reply;
        mpo_netinet_tcp_reply_t                 *mpo_netinet_tcp_reply;

        mpo_pipe_check_ioctl_t                  *mpo_pipe_check_ioctl;
        mpo_pipe_check_kqfilter_t               *mpo_pipe_check_kqfilter;
        mpo_pipe_check_label_update_t           *mpo_pipe_check_label_update;
        mpo_pipe_check_read_t                   *mpo_pipe_check_read;
        mpo_pipe_check_select_t                 *mpo_pipe_check_select;
        mpo_pipe_check_stat_t                   *mpo_pipe_check_stat;
        mpo_pipe_check_write_t                  *mpo_pipe_check_write;
        mpo_pipe_label_associate_t              *mpo_pipe_label_associate;
        mpo_pipe_label_copy_t                   *mpo_pipe_label_copy;
        mpo_pipe_label_destroy_t                *mpo_pipe_label_destroy;
        mpo_pipe_label_externalize_t            *mpo_pipe_label_externalize;
        mpo_pipe_label_init_t                   *mpo_pipe_label_init;
        mpo_pipe_label_internalize_t            *mpo_pipe_label_internalize;
        mpo_pipe_label_update_t                 *mpo_pipe_label_update;

        mpo_policy_destroy_t                    *mpo_policy_destroy;
        mpo_policy_init_t                       *mpo_policy_init;
        mpo_policy_initbsd_t                    *mpo_policy_initbsd;
        mpo_policy_syscall_t                    *mpo_policy_syscall;

        mpo_system_check_sysctlbyname_t         *mpo_system_check_sysctlbyname;
        mpo_proc_check_inherit_ipc_ports_t      *mpo_proc_check_inherit_ipc_ports;
        mpo_vnode_check_rename_t                *mpo_vnode_check_rename;
        mpo_kext_check_query_t                  *mpo_kext_check_query;
        mpo_proc_notify_exec_complete_t         *mpo_proc_notify_exec_complete;
        mpo_reserved_hook_t                     *mpo_reserved5;
        mpo_reserved_hook_t                     *mpo_reserved6;
        mpo_proc_check_expose_task_t            *mpo_proc_check_expose_task;
        mpo_proc_check_set_host_special_port_t  *mpo_proc_check_set_host_special_port;
        mpo_proc_check_set_host_exception_port_t *mpo_proc_check_set_host_exception_port;
        mpo_exc_action_check_exception_send_t   *mpo_exc_action_check_exception_send;
        mpo_exc_action_label_associate_t        *mpo_exc_action_label_associate;
        mpo_exc_action_label_populate_t         *mpo_exc_action_label_populate;
        mpo_exc_action_label_destroy_t          *mpo_exc_action_label_destroy;
        mpo_exc_action_label_init_t             *mpo_exc_action_label_init;
        mpo_exc_action_label_update_t           *mpo_exc_action_label_update;

        mpo_vnode_check_trigger_resolve_t       *mpo_vnode_check_trigger_resolve;
        mpo_reserved_hook_t                     *mpo_reserved1;
        mpo_reserved_hook_t                     *mpo_reserved2;
        mpo_reserved_hook_t                     *mpo_reserved3;
        mpo_skywalk_flow_check_connect_t        *mpo_skywalk_flow_check_connect;
        mpo_skywalk_flow_check_listen_t         *mpo_skywalk_flow_check_listen;

        mpo_posixsem_check_create_t             *mpo_posixsem_check_create;
        mpo_posixsem_check_open_t               *mpo_posixsem_check_open;
        mpo_posixsem_check_post_t               *mpo_posixsem_check_post;
        mpo_posixsem_check_unlink_t             *mpo_posixsem_check_unlink;
        mpo_posixsem_check_wait_t               *mpo_posixsem_check_wait;
        mpo_posixsem_label_associate_t          *mpo_posixsem_label_associate;
        mpo_posixsem_label_destroy_t            *mpo_posixsem_label_destroy;
        mpo_posixsem_label_init_t               *mpo_posixsem_label_init;
        mpo_posixshm_check_create_t             *mpo_posixshm_check_create;
        mpo_posixshm_check_mmap_t               *mpo_posixshm_check_mmap;
        mpo_posixshm_check_open_t               *mpo_posixshm_check_open;
        mpo_posixshm_check_stat_t               *mpo_posixshm_check_stat;
        mpo_posixshm_check_truncate_t           *mpo_posixshm_check_truncate;
        mpo_posixshm_check_unlink_t             *mpo_posixshm_check_unlink;
        mpo_posixshm_label_associate_t          *mpo_posixshm_label_associate;
        mpo_posixshm_label_destroy_t            *mpo_posixshm_label_destroy;
        mpo_posixshm_label_init_t               *mpo_posixshm_label_init;

        mpo_proc_check_debug_t                  *mpo_proc_check_debug;
        mpo_proc_check_fork_t                   *mpo_proc_check_fork;
        mpo_proc_check_get_task_name_t          *mpo_proc_check_get_task_name;
        mpo_proc_check_get_task_t               *mpo_proc_check_get_task;
        mpo_proc_check_getaudit_t               *mpo_proc_check_getaudit;
        mpo_proc_check_getauid_t                *mpo_proc_check_getauid;
        mpo_proc_check_getlcid_t                *mpo_proc_check_getlcid;
        mpo_proc_check_mprotect_t               *mpo_proc_check_mprotect;
        mpo_proc_check_sched_t                  *mpo_proc_check_sched;
        mpo_proc_check_setaudit_t               *mpo_proc_check_setaudit;
        mpo_proc_check_setauid_t                *mpo_proc_check_setauid;
        mpo_proc_check_setlcid_t                *mpo_proc_check_setlcid;
        mpo_proc_check_signal_t                 *mpo_proc_check_signal;
        mpo_proc_check_wait_t                   *mpo_proc_check_wait;
        mpo_proc_label_destroy_t                *mpo_proc_label_destroy;
        mpo_proc_label_init_t                   *mpo_proc_label_init;

        mpo_socket_check_accept_t               *mpo_socket_check_accept;
        mpo_socket_check_accepted_t             *mpo_socket_check_accepted;
        mpo_socket_check_bind_t                 *mpo_socket_check_bind;
        mpo_socket_check_connect_t              *mpo_socket_check_connect;
        mpo_socket_check_create_t               *mpo_socket_check_create;
        mpo_socket_check_deliver_t              *mpo_socket_check_deliver;
        mpo_socket_check_kqfilter_t             *mpo_socket_check_kqfilter;
        mpo_socket_check_label_update_t         *mpo_socket_check_label_update;
        mpo_socket_check_listen_t               *mpo_socket_check_listen;
        mpo_socket_check_receive_t              *mpo_socket_check_receive;
        mpo_socket_check_received_t             *mpo_socket_check_received;
        mpo_socket_check_select_t               *mpo_socket_check_select;
        mpo_socket_check_send_t                 *mpo_socket_check_send;
        mpo_socket_check_stat_t                 *mpo_socket_check_stat;
        mpo_socket_check_setsockopt_t           *mpo_socket_check_setsockopt;
        mpo_socket_check_getsockopt_t           *mpo_socket_check_getsockopt;
        mpo_socket_label_associate_accept_t     *mpo_socket_label_associate_accept;
        mpo_socket_label_associate_t            *mpo_socket_label_associate;
        mpo_socket_label_copy_t                 *mpo_socket_label_copy;
        mpo_socket_label_destroy_t              *mpo_socket_label_destroy;
        mpo_socket_label_externalize_t          *mpo_socket_label_externalize;
        mpo_socket_label_init_t                 *mpo_socket_label_init;
        mpo_socket_label_internalize_t          *mpo_socket_label_internalize;
        mpo_socket_label_update_t               *mpo_socket_label_update;

        mpo_socketpeer_label_associate_mbuf_t   *mpo_socketpeer_label_associate_mbuf;
        mpo_socketpeer_label_associate_socket_t *mpo_socketpeer_label_associate_socket;
        mpo_socketpeer_label_destroy_t          *mpo_socketpeer_label_destroy;
        mpo_socketpeer_label_externalize_t      *mpo_socketpeer_label_externalize;
        mpo_socketpeer_label_init_t             *mpo_socketpeer_label_init;

        mpo_system_check_acct_t                 *mpo_system_check_acct;
        mpo_system_check_audit_t                *mpo_system_check_audit;
        mpo_system_check_auditctl_t             *mpo_system_check_auditctl;
        mpo_system_check_auditon_t              *mpo_system_check_auditon;
        mpo_system_check_host_priv_t            *mpo_system_check_host_priv;
        mpo_system_check_nfsd_t                 *mpo_system_check_nfsd;
        mpo_system_check_reboot_t               *mpo_system_check_reboot;
        mpo_system_check_settime_t              *mpo_system_check_settime;
        mpo_system_check_swapoff_t              *mpo_system_check_swapoff;
        mpo_system_check_swapon_t               *mpo_system_check_swapon;
        mpo_socket_check_ioctl_t                *mpo_socket_check_ioctl;

        mpo_sysvmsg_label_associate_t           *mpo_sysvmsg_label_associate;
        mpo_sysvmsg_label_destroy_t             *mpo_sysvmsg_label_destroy;
        mpo_sysvmsg_label_init_t                *mpo_sysvmsg_label_init;
        mpo_sysvmsg_label_recycle_t             *mpo_sysvmsg_label_recycle;
        mpo_sysvmsq_check_enqueue_t             *mpo_sysvmsq_check_enqueue;
        mpo_sysvmsq_check_msgrcv_t              *mpo_sysvmsq_check_msgrcv;
        mpo_sysvmsq_check_msgrmid_t             *mpo_sysvmsq_check_msgrmid;
        mpo_sysvmsq_check_msqctl_t              *mpo_sysvmsq_check_msqctl;
        mpo_sysvmsq_check_msqget_t              *mpo_sysvmsq_check_msqget;
        mpo_sysvmsq_check_msqrcv_t              *mpo_sysvmsq_check_msqrcv;
        mpo_sysvmsq_check_msqsnd_t              *mpo_sysvmsq_check_msqsnd;
        mpo_sysvmsq_label_associate_t           *mpo_sysvmsq_label_associate;
        mpo_sysvmsq_label_destroy_t             *mpo_sysvmsq_label_destroy;
        mpo_sysvmsq_label_init_t                *mpo_sysvmsq_label_init;
        mpo_sysvmsq_label_recycle_t             *mpo_sysvmsq_label_recycle;
        mpo_sysvsem_check_semctl_t              *mpo_sysvsem_check_semctl;
        mpo_sysvsem_check_semget_t              *mpo_sysvsem_check_semget;
        mpo_sysvsem_check_semop_t               *mpo_sysvsem_check_semop;
        mpo_sysvsem_label_associate_t           *mpo_sysvsem_label_associate;
        mpo_sysvsem_label_destroy_t             *mpo_sysvsem_label_destroy;
        mpo_sysvsem_label_init_t                *mpo_sysvsem_label_init;
        mpo_sysvsem_label_recycle_t             *mpo_sysvsem_label_recycle;
        mpo_sysvshm_check_shmat_t               *mpo_sysvshm_check_shmat;
        mpo_sysvshm_check_shmctl_t              *mpo_sysvshm_check_shmctl;
        mpo_sysvshm_check_shmdt_t               *mpo_sysvshm_check_shmdt;
        mpo_sysvshm_check_shmget_t              *mpo_sysvshm_check_shmget;
        mpo_sysvshm_label_associate_t           *mpo_sysvshm_label_associate;
        mpo_sysvshm_label_destroy_t             *mpo_sysvshm_label_destroy;
        mpo_sysvshm_label_init_t                *mpo_sysvshm_label_init;
        mpo_sysvshm_label_recycle_t             *mpo_sysvshm_label_recycle;

        mpo_proc_notify_exit_t                  *mpo_proc_notify_exit;
        mpo_mount_check_snapshot_revert_t       *mpo_mount_check_snapshot_revert;
        mpo_vnode_check_getattr_t               *mpo_vnode_check_getattr;
        mpo_mount_check_snapshot_create_t       *mpo_mount_check_snapshot_create;
        mpo_mount_check_snapshot_delete_t       *mpo_mount_check_snapshot_delete;
        mpo_vnode_check_clone_t                 *mpo_vnode_check_clone;
        mpo_proc_check_get_cs_info_t            *mpo_proc_check_get_cs_info;
        mpo_proc_check_set_cs_info_t            *mpo_proc_check_set_cs_info;

        mpo_iokit_check_hid_control_t           *mpo_iokit_check_hid_control;

        mpo_vnode_check_access_t                *mpo_vnode_check_access;
        mpo_vnode_check_chdir_t                 *mpo_vnode_check_chdir;
        mpo_vnode_check_chroot_t                *mpo_vnode_check_chroot;
        mpo_vnode_check_create_t                *mpo_vnode_check_create;
        mpo_vnode_check_deleteextattr_t         *mpo_vnode_check_deleteextattr;
        mpo_vnode_check_exchangedata_t          *mpo_vnode_check_exchangedata;
        mpo_vnode_check_exec_t                  *mpo_vnode_check_exec;
        mpo_vnode_check_getattrlist_t           *mpo_vnode_check_getattrlist;
        mpo_vnode_check_getextattr_t            *mpo_vnode_check_getextattr;
        mpo_vnode_check_ioctl_t                 *mpo_vnode_check_ioctl;
        mpo_vnode_check_kqfilter_t              *mpo_vnode_check_kqfilter;
        mpo_vnode_check_label_update_t          *mpo_vnode_check_label_update;
        mpo_vnode_check_link_t                  *mpo_vnode_check_link;
        mpo_vnode_check_listextattr_t           *mpo_vnode_check_listextattr;
        mpo_vnode_check_lookup_t                *mpo_vnode_check_lookup;
        mpo_vnode_check_open_t                  *mpo_vnode_check_open;
        mpo_vnode_check_read_t                  *mpo_vnode_check_read;
        mpo_vnode_check_readdir_t               *mpo_vnode_check_readdir;
        mpo_vnode_check_readlink_t              *mpo_vnode_check_readlink;
        mpo_vnode_check_rename_from_t           *mpo_vnode_check_rename_from;
        mpo_vnode_check_rename_to_t             *mpo_vnode_check_rename_to;
        mpo_vnode_check_revoke_t                *mpo_vnode_check_revoke;
        mpo_vnode_check_select_t                *mpo_vnode_check_select;
        mpo_vnode_check_setattrlist_t           *mpo_vnode_check_setattrlist;
        mpo_vnode_check_setextattr_t            *mpo_vnode_check_setextattr;
        mpo_vnode_check_setflags_t              *mpo_vnode_check_setflags;
        mpo_vnode_check_setmode_t               *mpo_vnode_check_setmode;
        mpo_vnode_check_setowner_t              *mpo_vnode_check_setowner;
        mpo_vnode_check_setutimes_t             *mpo_vnode_check_setutimes;
        mpo_vnode_check_stat_t                  *mpo_vnode_check_stat;
        mpo_vnode_check_truncate_t              *mpo_vnode_check_truncate;
        mpo_vnode_check_unlink_t                *mpo_vnode_check_unlink;
        mpo_vnode_check_write_t                 *mpo_vnode_check_write;
        mpo_vnode_label_associate_devfs_t       *mpo_vnode_label_associate_devfs;
        mpo_vnode_label_associate_extattr_t     *mpo_vnode_label_associate_extattr;
        mpo_vnode_label_associate_file_t        *mpo_vnode_label_associate_file;
        mpo_vnode_label_associate_pipe_t        *mpo_vnode_label_associate_pipe;
        mpo_vnode_label_associate_posixsem_t    *mpo_vnode_label_associate_posixsem;
        mpo_vnode_label_associate_posixshm_t    *mpo_vnode_label_associate_posixshm;
        mpo_vnode_label_associate_singlelabel_t *mpo_vnode_label_associate_singlelabel;
        mpo_vnode_label_associate_socket_t      *mpo_vnode_label_associate_socket;
        mpo_vnode_label_copy_t                  *mpo_vnode_label_copy;
        mpo_vnode_label_destroy_t               *mpo_vnode_label_destroy;
        mpo_vnode_label_externalize_audit_t     *mpo_vnode_label_externalize_audit;
        mpo_vnode_label_externalize_t           *mpo_vnode_label_externalize;
        mpo_vnode_label_init_t                  *mpo_vnode_label_init;
        mpo_vnode_label_internalize_t           *mpo_vnode_label_internalize;
        mpo_vnode_label_recycle_t               *mpo_vnode_label_recycle;
        mpo_vnode_label_store_t                 *mpo_vnode_label_store;
        mpo_vnode_label_update_extattr_t        *mpo_vnode_label_update_extattr;
        mpo_vnode_label_update_t                *mpo_vnode_label_update;
        mpo_vnode_notify_create_t               *mpo_vnode_notify_create;
        mpo_vnode_check_signature_t             *mpo_vnode_check_signature;
        mpo_vnode_check_uipc_bind_t             *mpo_vnode_check_uipc_bind;
        mpo_vnode_check_uipc_connect_t          *mpo_vnode_check_uipc_connect;

        mpo_proc_check_run_cs_invalid_t         *mpo_proc_check_run_cs_invalid;
        mpo_proc_check_suspend_resume_t         *mpo_proc_check_suspend_resume;

        mpo_thread_userret_t                    *mpo_thread_userret;

        mpo_iokit_check_set_properties_t        *mpo_iokit_check_set_properties;

        mpo_system_check_chud_t                 *mpo_system_check_chud;

        mpo_vnode_check_searchfs_t              *mpo_vnode_check_searchfs;

        mpo_priv_check_t                        *mpo_priv_check;
        mpo_priv_grant_t                        *mpo_priv_grant;

        mpo_proc_check_map_anon_t               *mpo_proc_check_map_anon;

        mpo_vnode_check_fsgetpath_t             *mpo_vnode_check_fsgetpath;

        mpo_iokit_check_open_t                  *mpo_iokit_check_open;

        mpo_proc_check_ledger_t                 *mpo_proc_check_ledger;

        mpo_vnode_notify_rename_t               *mpo_vnode_notify_rename;

        mpo_vnode_check_setacl_t                *mpo_vnode_check_setacl;

        mpo_vnode_notify_deleteextattr_t        *mpo_vnode_notify_deleteextattr;

        mpo_system_check_kas_info_t             *mpo_system_check_kas_info;

        mpo_vnode_check_lookup_preflight_t      *mpo_vnode_check_lookup_preflight;

        mpo_vnode_notify_open_t                 *mpo_vnode_notify_open;

        mpo_system_check_info_t                 *mpo_system_check_info;

        mpo_pty_notify_grant_t                  *mpo_pty_notify_grant;
        mpo_pty_notify_close_t                  *mpo_pty_notify_close;

        mpo_vnode_find_sigs_t                   *mpo_vnode_find_sigs;

        mpo_kext_check_load_t                   *mpo_kext_check_load;
        mpo_kext_check_unload_t                 *mpo_kext_check_unload;

        mpo_proc_check_proc_info_t              *mpo_proc_check_proc_info;
        mpo_vnode_notify_link_t                 *mpo_vnode_notify_link;
        mpo_iokit_check_filter_properties_t     *mpo_iokit_check_filter_properties;
        mpo_iokit_check_get_property_t          *mpo_iokit_check_get_property;
};

/**
 *  @brief MAC policy handle type
 *
 *  The MAC handle is used to uniquely identify a loaded policy within
 *  the MAC Framework.
 *
 *  A variable of this type is set by mac_policy_register().
 */
typedef unsigned int mac_policy_handle_t;

#define mpc_t   struct mac_policy_conf *

/**
 *  @brief Mac policy configuration
 *
 *  This structure specifies the configuration information for a
 *  MAC policy module.  A policy module developer must supply
 *  a short unique policy name, a more descriptive full name, a list of label
 *  namespaces and count, a pointer to the registered enty point operations,
 *  any load time flags, and optionally, a pointer to a label slot identifier.
 *
 *  The Framework will update the runtime flags (mpc_runtime_flags) to
 *  indicate that the module has been registered.
 *
 *  If the label slot identifier (mpc_field_off) is NULL, the Framework
 *  will not provide label storage for the policy.  Otherwise, the
 *  Framework will store the label location (slot) in this field.
 *
 *  The mpc_list field is used by the Framework and should not be
 *  modified by policies.
 */
/* XXX - reorder these for better aligment on 64bit platforms */
struct mac_policy_conf {
        const char              *mpc_name;              /** policy name */
        const char              *mpc_fullname;          /** full name */
        char const * const *mpc_labelnames;     /** managed label namespaces */
        unsigned int             mpc_labelname_count;   /** number of managed label namespaces */
        const struct mac_policy_ops     *mpc_ops;               /** operation vector */
        int                      mpc_loadtime_flags;    /** load time flags */
        int                     *mpc_field_off;         /** label slot */
        int                      mpc_runtime_flags;     /** run time flags */
        mpc_t                    mpc_list;              /** List reference */
        void                    *mpc_data;              /** module data */
};

/**
 *  @brief MAC policy module registration routine
 *
 *  This function is called to register a policy with the
 *  MAC framework.  A policy module will typically call this from the
 *  Darwin KEXT registration routine.
 */
int     mac_policy_register(struct mac_policy_conf *mpc,
    mac_policy_handle_t *handlep, void *xd);

/**
 *  @brief MAC policy module de-registration routine
 *
 *  This function is called to de-register a policy with theD
 *  MAC framework.  A policy module will typically call this from the
 *  Darwin KEXT de-registration routine.
 */
int     mac_policy_unregister(mac_policy_handle_t handle);

/*
 * Framework entry points for the policies to add audit data.
 */
int     mac_audit_text(char *text, mac_policy_handle_t handle);

/*
 * Calls to assist with use of Apple XATTRs within policy modules.
 */
int     mac_vnop_setxattr(struct vnode *, const char *, char *, size_t);
int     mac_vnop_getxattr(struct vnode *, const char *, char *, size_t,
    size_t *);
int     mac_vnop_removexattr(struct vnode *, const char *);

/**
 *  @brief Set an extended attribute on a vnode-based fileglob.
 *  @param fg fileglob representing file to attach the extended attribute
 *  @param name extended attribute name
 *  @param buf buffer of data to use as the extended attribute value
 *  @param len size of buffer
 *
 *  Sets the value of an extended attribute on a file.
 *
 *  Caller must hold an iocount on the vnode represented by the fileglob.
 */
int     mac_file_setxattr(struct fileglob *fg, const char *name, char *buf, size_t len);

/**
 *       @brief Get an extended attribute from a vnode-based fileglob.
 *       @param fg fileglob representing file to read the extended attribute
 *       @param name extended attribute name
 *       @param buf buffer of data to hold the extended attribute value
 *       @param len size of buffer
 *       @param attrlen size of full extended attribute value
 *
 *       Gets the value of an extended attribute on a file.
 *
 *       Caller must hold an iocount on the vnode represented by the fileglob.
 */
int     mac_file_getxattr(struct fileglob *fg, const char *name, char *buf, size_t len,
    size_t *attrlen);

/**
 *       @brief Remove an extended attribute from a vnode-based fileglob.
 *       @param fg fileglob representing file to remove the extended attribute
 *       @param name extended attribute name
 *
 *       Removes the named extended attribute from the file.
 *
 *       Caller must hold an iocount on the vnode represented by the fileglob.
 */
int     mac_file_removexattr(struct fileglob *fg, const char *name);


/*
 * Arbitrary limit on how much data will be logged by the audit
 * entry points above.
 */
#define MAC_AUDIT_DATA_LIMIT    1024

/*
 * Values returned by mac_audit_{pre,post}select. To combine the responses
 * of the security policies into a single decision,
 * mac_audit_{pre,post}select() choose the greatest value returned.
 */
#define MAC_AUDIT_DEFAULT       0       /* use system behavior */
#define MAC_AUDIT_NO            1       /* force not auditing this event */
#define MAC_AUDIT_YES           2       /* force auditing this event */

//  \defgroup mpc_loadtime_flags Flags for the mpc_loadtime_flags field

/**
 *  @name Flags for the mpc_loadtime_flags field
 *  @see mac_policy_conf
 *
 *  This is the complete list of flags that are supported by the
 *  mpc_loadtime_flags field of the mac_policy_conf structure.  These
 *  flags specify the load time behavior of MAC Framework policy
 *  modules.
 */

/*@{*/

/**
 *  @brief Flag to indicate registration preference
 *
 *  This flag indicates that the policy module must be loaded and
 *  initialized early in the boot process. If the flag is specified,
 *  attempts to register the module following boot will be rejected. The
 *  flag may be used by policies that require pervasive labeling of all
 *  system objects, and cannot handle objects that have not been
 *  properly initialized by the policy.
 */
#define MPC_LOADTIME_FLAG_NOTLATE       0x00000001

/**
 *  @brief Flag to indicate unload preference
 *
 *  This flag indicates that the policy module may be unloaded. If this
 *  flag is not set, then the policy framework will reject requests to
 *  unload the module. This flag might be used by modules that allocate
 *  label state and are unable to free that state at runtime, or for
 *  modules that simply do not want to permit unload operations.
 */
#define MPC_LOADTIME_FLAG_UNLOADOK      0x00000002

/**
 *  @brief Unsupported
 *
 *  XXX This flag is not yet supported.
 */
#define MPC_LOADTIME_FLAG_LABELMBUFS    0x00000004

/**
 *  @brief Flag to indicate a base policy
 *
 *  This flag indicates that the policy module is a base policy. Only
 *  one module can declare itself as base, otherwise the boot process
 *  will be halted.
 */
#define MPC_LOADTIME_BASE_POLICY        0x00000008

/*@}*/

/**
 *  @brief Policy registration flag
 *  @see mac_policy_conf
 *
 *  This flag indicates that the policy module has been successfully
 *  registered with the TrustedBSD MAC Framework.  The Framework will
 *  set this flag in the mpc_runtime_flags field of the policy's
 *  mac_policy_conf structure after registering the policy.
 */
#define MPC_RUNTIME_FLAG_REGISTERED     0x00000001

/*
 * Depends on POLICY_VER
 */

#ifndef POLICY_VER
#define POLICY_VER      1.0
#endif

#define MAC_POLICY_SET(handle, mpops, mpname, mpfullname, lnames, lcount, slot, lflags, rflags) \
        static struct mac_policy_conf mpname##_mac_policy_conf = {      \
                .mpc_name               = #mpname,                      \
                .mpc_fullname           = mpfullname,                   \
                .mpc_labelnames         = lnames,                       \
                .mpc_labelname_count    = lcount,                       \
                .mpc_ops                = mpops,                        \
                .mpc_loadtime_flags     = lflags,                       \
                .mpc_field_off          = slot,                         \
                .mpc_runtime_flags      = rflags                        \
        };                                                              \
                                                                        \
        static kern_return_t                                            \
        kmod_start(kmod_info_t *ki, void *xd)                           \
        {                                                               \
                return mac_policy_register(&mpname##_mac_policy_conf,   \
                    &handle, xd);                                       \
        }                                                               \
                                                                        \
        static kern_return_t                                            \
        kmod_stop(kmod_info_t *ki, void *xd)                            \
        {                                                               \
                return mac_policy_unregister(handle);                   \
        }                                                               \
                                                                        \
        extern kern_return_t _start(kmod_info_t *ki, void *data);       \
        extern kern_return_t _stop(kmod_info_t *ki, void *data);        \
                                                                        \
        KMOD_EXPLICIT_DECL(security.mpname, POLICY_VER, _start, _stop)  \
        kmod_start_func_t *_realmain = kmod_start;                      \
        kmod_stop_func_t *_antimain = kmod_stop;                        \
        int _kext_apple_cc = __APPLE_CC__


#define LABEL_TO_SLOT(l, s)     (l)->l_perpolicy[s]

/*
 * Policy interface to map a struct label pointer to per-policy data.
 * Typically, policies wrap this in their own accessor macro that casts an
 * intptr_t to a policy-specific data type.
 */
intptr_t        mac_label_get(struct label *l, int slot);
void            mac_label_set(struct label *l, int slot, intptr_t v);

#define mac_get_mpc(h)          (mac_policy_list.entries[h].mpc)

/**
 *  @name Flags for MAC allocator interfaces
 *
 *  These flags are passed to the Darwin kernel allocator routines to
 *  indicate whether the allocation is permitted to block or not.
 *  Caution should be taken; some operations are not permitted to sleep,
 *  and some types of locks cannot be held when sleeping.
 */

/*@{*/

/**
 *   @brief Allocation operations may block
 *
 *   If memory is not immediately available, the allocation routine
 *   will block (typically sleeping) until memory is available.
 *
 *   @warning Inappropriate use of this flag may cause kernel panics.
 */
#define MAC_WAITOK  0

/**
 *   @brief Allocation operations may not block
 *
 *   Rather than blocking, the allocator may return an error if memory
 *   is not immediately available.  This type of allocation will not
 *   sleep, preserving locking semantics.
 */
#define MAC_NOWAIT  1

/*@}*/

#endif /* !_SECURITY_MAC_POLICY_H_ */