freebsd-dev/sys/security/mac/mac_posix_shm.c
Robert Watson 9b6dd12e5d Correct several issues in the integration of POSIX shared memory objects
and the new setmode and setowner fileops in FreeBSD 9.0:

- Add new MAC Framework entry point mac_posixshm_check_create() to allow
  MAC policies to authorise shared memory use.  Provide a stub policy and
  test policy templates.

- Add missing Biba and MLS implementations of mac_posixshm_check_setmode()
  and mac_posixshm_check_setowner().

- Add 'accmode' argument to mac_posixshm_check_open() -- unlike the
  mac_posixsem_check_open() entry point it was modeled on, the access mode
  is required as shared memory access can be read-only as well as writable;
  this isn't true of POSIX semaphores.

- Implement full range of POSIX shared memory entry points for Biba and MLS.

Sponsored by:   Google Inc.
Obtained from:	TrustedBSD Project
Approved by:    re (kib)
2011-09-02 17:40:39 +00:00

231 lines
6.1 KiB
C

/*-
* Copyright (c) 2003-2006 SPARTA, Inc.
* Copyright (c) 2009-2011 Robert N. M. Watson
* All rights reserved.
*
* 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"). *
*
* This software was developed at the University of Cambridge Computer
* Laboratory with support from a grant from Google, Inc.
*
* 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_kdtrace.h"
#include "opt_mac.h"
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/mman.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/sdt.h>
#include <sys/systm.h>
#include <sys/sysctl.h>
#include <security/mac/mac_framework.h>
#include <security/mac/mac_internal.h>
#include <security/mac/mac_policy.h>
static struct label *
mac_posixshm_label_alloc(void)
{
struct label *label;
label = mac_labelzone_alloc(M_WAITOK);
MAC_POLICY_PERFORM(posixshm_init_label, label);
return (label);
}
void
mac_posixshm_init(struct shmfd *shmfd)
{
if (mac_labeled & MPC_OBJECT_POSIXSHM)
shmfd->shm_label = mac_posixshm_label_alloc();
else
shmfd->shm_label = NULL;
}
static void
mac_posixshm_label_free(struct label *label)
{
MAC_POLICY_PERFORM_NOSLEEP(posixshm_destroy_label, label);
mac_labelzone_free(label);
}
void
mac_posixshm_destroy(struct shmfd *shmfd)
{
if (shmfd->shm_label != NULL) {
mac_posixshm_label_free(shmfd->shm_label);
shmfd->shm_label = NULL;
}
}
void
mac_posixshm_create(struct ucred *cred, struct shmfd *shmfd)
{
MAC_POLICY_PERFORM_NOSLEEP(posixshm_create, cred, shmfd,
shmfd->shm_label);
}
MAC_CHECK_PROBE_DEFINE2(posixshm_check_create, "struct ucred *",
"const char *");
int
mac_posixshm_check_create(struct ucred *cred, const char *path)
{
int error;
MAC_POLICY_CHECK_NOSLEEP(posixshm_check_create, cred, path);
MAC_CHECK_PROBE2(posixshm_check_create, error, cred, path);
return (error);
}
MAC_CHECK_PROBE_DEFINE4(posixshm_check_mmap, "struct ucred *",
"struct shmfd *", "int", "int");
int
mac_posixshm_check_mmap(struct ucred *cred, struct shmfd *shmfd, int prot,
int flags)
{
int error;
MAC_POLICY_CHECK_NOSLEEP(posixshm_check_mmap, cred, shmfd,
shmfd->shm_label, prot, flags);
MAC_CHECK_PROBE4(posixshm_check_mmap, error, cred, shmfd, prot,
flags);
return (error);
}
MAC_CHECK_PROBE_DEFINE3(posixshm_check_open, "struct ucred *",
"struct shmfd *", "accmode_t accmode");
int
mac_posixshm_check_open(struct ucred *cred, struct shmfd *shmfd,
accmode_t accmode)
{
int error;
MAC_POLICY_CHECK_NOSLEEP(posixshm_check_open, cred, shmfd,
shmfd->shm_label, accmode);
MAC_CHECK_PROBE3(posixshm_check_open, error, cred, shmfd, accmode);
return (error);
}
MAC_CHECK_PROBE_DEFINE3(posixshm_check_stat, "struct ucred *",
"struct ucred *", "struct shmfd *");
int
mac_posixshm_check_stat(struct ucred *active_cred, struct ucred *file_cred,
struct shmfd *shmfd)
{
int error;
MAC_POLICY_CHECK_NOSLEEP(posixshm_check_stat, active_cred, file_cred,
shmfd, shmfd->shm_label);
MAC_CHECK_PROBE3(posixshm_check_stat, error, active_cred, file_cred,
shmfd);
return (error);
}
MAC_CHECK_PROBE_DEFINE3(posixshm_check_truncate, "struct ucred *",
"struct ucred *", "struct shmfd *");
int
mac_posixshm_check_truncate(struct ucred *active_cred, struct ucred *file_cred,
struct shmfd *shmfd)
{
int error;
MAC_POLICY_CHECK_NOSLEEP(posixshm_check_truncate, active_cred,
file_cred, shmfd, shmfd->shm_label);
MAC_CHECK_PROBE3(posixshm_check_truncate, error, active_cred,
file_cred, shmfd);
return (error);
}
MAC_CHECK_PROBE_DEFINE2(posixshm_check_unlink, "struct ucred *",
"struct shmfd *");
int
mac_posixshm_check_unlink(struct ucred *cred, struct shmfd *shmfd)
{
int error;
MAC_POLICY_CHECK_NOSLEEP(posixshm_check_unlink, cred, shmfd,
shmfd->shm_label);
MAC_CHECK_PROBE2(posixshm_check_unlink, error, cred, shmfd);
return (error);
}
MAC_CHECK_PROBE_DEFINE3(posixshm_check_setmode, "struct ucred *",
"struct shmfd *", "mode_t");
int
mac_posixshm_check_setmode(struct ucred *cred, struct shmfd *shmfd, mode_t mode)
{
int error;
MAC_POLICY_CHECK_NOSLEEP(posixshm_check_setmode, cred, shmfd,
shmfd->shm_label, mode);
MAC_CHECK_PROBE3(posixshm_check_setmode, error, cred, shmfd, mode);
return (error);
}
MAC_CHECK_PROBE_DEFINE4(posixshm_check_setowner, "struct ucred *",
"struct shmfd *", "uid_t", "gid_t");
int
mac_posixshm_check_setowner(struct ucred *cred, struct shmfd *shmfd, uid_t uid,
gid_t gid)
{
int error;
MAC_POLICY_CHECK_NOSLEEP(posixshm_check_setowner, cred, shmfd,
shmfd->shm_label, uid, gid);
MAC_CHECK_PROBE4(posixshm_check_setowner, error, cred, shmfd,
uid, gid);
return (error);
}