freebsd-dev/sys/security/mac_partition/mac_partition.c

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/*-
* Copyright (c) 1999-2002 Robert N. M. Watson
* Copyright (c) 2001-2002 Networks Associates Technology, 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.
*
* 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.
*
* $FreeBSD$
*/
/*
* Developed by the TrustedBSD Project.
* Experiment with a partition-like model.
*/
#include <sys/types.h>
#include <sys/param.h>
#include <sys/conf.h>
#include <sys/kernel.h>
#include <sys/mac.h>
#include <sys/mount.h>
#include <sys/proc.h>
#include <sys/sbuf.h>
#include <sys/systm.h>
#include <sys/sysproto.h>
#include <sys/sysent.h>
#include <sys/vnode.h>
#include <sys/file.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sysctl.h>
#include <fs/devfs/devfs.h>
#include <net/bpfdesc.h>
#include <net/if.h>
#include <net/if_types.h>
#include <net/if_var.h>
#include <vm/vm.h>
#include <sys/mac_policy.h>
#include <security/mac_partition/mac_partition.h>
SYSCTL_DECL(_security_mac);
SYSCTL_NODE(_security_mac, OID_AUTO, partition, CTLFLAG_RW, 0,
"TrustedBSD mac_partition policy controls");
static int mac_partition_enabled = 1;
SYSCTL_INT(_security_mac_partition, OID_AUTO, enabled, CTLFLAG_RW,
&mac_partition_enabled, 0, "Enforce partition policy");
static int partition_slot;
#define SLOT(l) (LABEL_TO_SLOT((l), partition_slot).l_long)
static void
mac_partition_init(struct mac_policy_conf *conf)
{
}
static void
mac_partition_init_label(struct label *label)
{
SLOT(label) = 0;
}
static void
mac_partition_destroy_label(struct label *label)
{
SLOT(label) = 0;
}
static void
mac_partition_copy_label(struct label *src, struct label *dest)
{
SLOT(dest) = SLOT(src);
}
static int
mac_partition_externalize_label(struct label *label, char *element_name,
struct sbuf *sb, int *claimed)
{
if (strcmp(MAC_PARTITION_LABEL_NAME, element_name) != 0)
return (0);
(*claimed)++;
if (sbuf_printf(sb, "%ld", SLOT(label)) == -1)
return (EINVAL);
else
return (0);
}
static int
mac_partition_internalize_label(struct label *label, char *element_name,
char *element_data, int *claimed)
{
if (strcmp(MAC_PARTITION_LABEL_NAME, element_name) != 0)
return (0);
(*claimed)++;
SLOT(label) = strtol(element_data, NULL, 10);
return (0);
}
static void
mac_partition_create_proc0(struct ucred *cred)
{
Modify the MAC Framework so that instead of embedding a (struct label) in various kernel objects to represent security data, we embed a (struct label *) pointer, which now references labels allocated using a UMA zone (mac_label.c). This allows the size and shape of struct label to be varied without changing the size and shape of these kernel objects, which become part of the frozen ABI with 5-STABLE. This opens the door for boot-time selection of the number of label slots, and hence changes to the bound on the number of simultaneous labeled policies at boot-time instead of compile-time. This also makes it easier to embed label references in new objects as required for locking/caching with fine-grained network stack locking, such as inpcb structures. This change also moves us further in the direction of hiding the structure of kernel objects from MAC policy modules, not to mention dramatically reducing the number of '&' symbols appearing in both the MAC Framework and MAC policy modules, and improving readability. While this results in minimal performance change with MAC enabled, it will observably shrink the size of a number of critical kernel data structures for the !MAC case, and should have a small (but measurable) performance benefit (i.e., struct vnode, struct socket) do to memory conservation and reduced cost of zeroing memory. NOTE: Users of MAC must recompile their kernel and all MAC modules as a result of this change. Because this is an API change, third party MAC modules will also need to be updated to make less use of the '&' symbol. Suggestions from: bmilekic Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-11-12 03:14:31 +00:00
SLOT(cred->cr_label) = 0;
}
static void
mac_partition_create_proc1(struct ucred *cred)
{
Modify the MAC Framework so that instead of embedding a (struct label) in various kernel objects to represent security data, we embed a (struct label *) pointer, which now references labels allocated using a UMA zone (mac_label.c). This allows the size and shape of struct label to be varied without changing the size and shape of these kernel objects, which become part of the frozen ABI with 5-STABLE. This opens the door for boot-time selection of the number of label slots, and hence changes to the bound on the number of simultaneous labeled policies at boot-time instead of compile-time. This also makes it easier to embed label references in new objects as required for locking/caching with fine-grained network stack locking, such as inpcb structures. This change also moves us further in the direction of hiding the structure of kernel objects from MAC policy modules, not to mention dramatically reducing the number of '&' symbols appearing in both the MAC Framework and MAC policy modules, and improving readability. While this results in minimal performance change with MAC enabled, it will observably shrink the size of a number of critical kernel data structures for the !MAC case, and should have a small (but measurable) performance benefit (i.e., struct vnode, struct socket) do to memory conservation and reduced cost of zeroing memory. NOTE: Users of MAC must recompile their kernel and all MAC modules as a result of this change. Because this is an API change, third party MAC modules will also need to be updated to make less use of the '&' symbol. Suggestions from: bmilekic Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-11-12 03:14:31 +00:00
SLOT(cred->cr_label) = 0;
}
static void
mac_partition_relabel_cred(struct ucred *cred, struct label *newlabel)
{
if (SLOT(newlabel) != 0)
Modify the MAC Framework so that instead of embedding a (struct label) in various kernel objects to represent security data, we embed a (struct label *) pointer, which now references labels allocated using a UMA zone (mac_label.c). This allows the size and shape of struct label to be varied without changing the size and shape of these kernel objects, which become part of the frozen ABI with 5-STABLE. This opens the door for boot-time selection of the number of label slots, and hence changes to the bound on the number of simultaneous labeled policies at boot-time instead of compile-time. This also makes it easier to embed label references in new objects as required for locking/caching with fine-grained network stack locking, such as inpcb structures. This change also moves us further in the direction of hiding the structure of kernel objects from MAC policy modules, not to mention dramatically reducing the number of '&' symbols appearing in both the MAC Framework and MAC policy modules, and improving readability. While this results in minimal performance change with MAC enabled, it will observably shrink the size of a number of critical kernel data structures for the !MAC case, and should have a small (but measurable) performance benefit (i.e., struct vnode, struct socket) do to memory conservation and reduced cost of zeroing memory. NOTE: Users of MAC must recompile their kernel and all MAC modules as a result of this change. Because this is an API change, third party MAC modules will also need to be updated to make less use of the '&' symbol. Suggestions from: bmilekic Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-11-12 03:14:31 +00:00
SLOT(cred->cr_label) = SLOT(newlabel);
}
static int
label_on_label(struct label *subject, struct label *object)
{
if (mac_partition_enabled == 0)
return (0);
if (SLOT(subject) == 0)
return (0);
if (SLOT(subject) == SLOT(object))
return (0);
return (EPERM);
}
static int
mac_partition_check_cred_relabel(struct ucred *cred, struct label *newlabel)
{
int error;
error = 0;
/* Treat "0" as a no-op request. */
if (SLOT(newlabel) != 0) {
/*
* Require BSD privilege in order to change the partition.
* Originally we also required that the process not be
* in a partition in the first place, but this didn't
* interact well with sendmail.
*/
error = suser_cred(cred, 0);
}
return (error);
}
static int
mac_partition_check_cred_visible(struct ucred *u1, struct ucred *u2)
{
int error;
Modify the MAC Framework so that instead of embedding a (struct label) in various kernel objects to represent security data, we embed a (struct label *) pointer, which now references labels allocated using a UMA zone (mac_label.c). This allows the size and shape of struct label to be varied without changing the size and shape of these kernel objects, which become part of the frozen ABI with 5-STABLE. This opens the door for boot-time selection of the number of label slots, and hence changes to the bound on the number of simultaneous labeled policies at boot-time instead of compile-time. This also makes it easier to embed label references in new objects as required for locking/caching with fine-grained network stack locking, such as inpcb structures. This change also moves us further in the direction of hiding the structure of kernel objects from MAC policy modules, not to mention dramatically reducing the number of '&' symbols appearing in both the MAC Framework and MAC policy modules, and improving readability. While this results in minimal performance change with MAC enabled, it will observably shrink the size of a number of critical kernel data structures for the !MAC case, and should have a small (but measurable) performance benefit (i.e., struct vnode, struct socket) do to memory conservation and reduced cost of zeroing memory. NOTE: Users of MAC must recompile their kernel and all MAC modules as a result of this change. Because this is an API change, third party MAC modules will also need to be updated to make less use of the '&' symbol. Suggestions from: bmilekic Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-11-12 03:14:31 +00:00
error = label_on_label(u1->cr_label, u2->cr_label);
return (error == 0 ? 0 : ESRCH);
}
static int
mac_partition_check_proc_debug(struct ucred *cred, struct proc *proc)
{
int error;
Modify the MAC Framework so that instead of embedding a (struct label) in various kernel objects to represent security data, we embed a (struct label *) pointer, which now references labels allocated using a UMA zone (mac_label.c). This allows the size and shape of struct label to be varied without changing the size and shape of these kernel objects, which become part of the frozen ABI with 5-STABLE. This opens the door for boot-time selection of the number of label slots, and hence changes to the bound on the number of simultaneous labeled policies at boot-time instead of compile-time. This also makes it easier to embed label references in new objects as required for locking/caching with fine-grained network stack locking, such as inpcb structures. This change also moves us further in the direction of hiding the structure of kernel objects from MAC policy modules, not to mention dramatically reducing the number of '&' symbols appearing in both the MAC Framework and MAC policy modules, and improving readability. While this results in minimal performance change with MAC enabled, it will observably shrink the size of a number of critical kernel data structures for the !MAC case, and should have a small (but measurable) performance benefit (i.e., struct vnode, struct socket) do to memory conservation and reduced cost of zeroing memory. NOTE: Users of MAC must recompile their kernel and all MAC modules as a result of this change. Because this is an API change, third party MAC modules will also need to be updated to make less use of the '&' symbol. Suggestions from: bmilekic Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-11-12 03:14:31 +00:00
error = label_on_label(cred->cr_label, proc->p_ucred->cr_label);
return (error ? ESRCH : 0);
}
static int
mac_partition_check_proc_sched(struct ucred *cred, struct proc *proc)
{
int error;
Modify the MAC Framework so that instead of embedding a (struct label) in various kernel objects to represent security data, we embed a (struct label *) pointer, which now references labels allocated using a UMA zone (mac_label.c). This allows the size and shape of struct label to be varied without changing the size and shape of these kernel objects, which become part of the frozen ABI with 5-STABLE. This opens the door for boot-time selection of the number of label slots, and hence changes to the bound on the number of simultaneous labeled policies at boot-time instead of compile-time. This also makes it easier to embed label references in new objects as required for locking/caching with fine-grained network stack locking, such as inpcb structures. This change also moves us further in the direction of hiding the structure of kernel objects from MAC policy modules, not to mention dramatically reducing the number of '&' symbols appearing in both the MAC Framework and MAC policy modules, and improving readability. While this results in minimal performance change with MAC enabled, it will observably shrink the size of a number of critical kernel data structures for the !MAC case, and should have a small (but measurable) performance benefit (i.e., struct vnode, struct socket) do to memory conservation and reduced cost of zeroing memory. NOTE: Users of MAC must recompile their kernel and all MAC modules as a result of this change. Because this is an API change, third party MAC modules will also need to be updated to make less use of the '&' symbol. Suggestions from: bmilekic Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-11-12 03:14:31 +00:00
error = label_on_label(cred->cr_label, proc->p_ucred->cr_label);
return (error ? ESRCH : 0);
}
static int
mac_partition_check_proc_signal(struct ucred *cred, struct proc *proc,
int signum)
{
int error;
Modify the MAC Framework so that instead of embedding a (struct label) in various kernel objects to represent security data, we embed a (struct label *) pointer, which now references labels allocated using a UMA zone (mac_label.c). This allows the size and shape of struct label to be varied without changing the size and shape of these kernel objects, which become part of the frozen ABI with 5-STABLE. This opens the door for boot-time selection of the number of label slots, and hence changes to the bound on the number of simultaneous labeled policies at boot-time instead of compile-time. This also makes it easier to embed label references in new objects as required for locking/caching with fine-grained network stack locking, such as inpcb structures. This change also moves us further in the direction of hiding the structure of kernel objects from MAC policy modules, not to mention dramatically reducing the number of '&' symbols appearing in both the MAC Framework and MAC policy modules, and improving readability. While this results in minimal performance change with MAC enabled, it will observably shrink the size of a number of critical kernel data structures for the !MAC case, and should have a small (but measurable) performance benefit (i.e., struct vnode, struct socket) do to memory conservation and reduced cost of zeroing memory. NOTE: Users of MAC must recompile their kernel and all MAC modules as a result of this change. Because this is an API change, third party MAC modules will also need to be updated to make less use of the '&' symbol. Suggestions from: bmilekic Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-11-12 03:14:31 +00:00
error = label_on_label(cred->cr_label, proc->p_ucred->cr_label);
return (error ? ESRCH : 0);
}
static int
mac_partition_check_socket_visible(struct ucred *cred, struct socket *socket,
struct label *socketlabel)
{
int error;
Modify the MAC Framework so that instead of embedding a (struct label) in various kernel objects to represent security data, we embed a (struct label *) pointer, which now references labels allocated using a UMA zone (mac_label.c). This allows the size and shape of struct label to be varied without changing the size and shape of these kernel objects, which become part of the frozen ABI with 5-STABLE. This opens the door for boot-time selection of the number of label slots, and hence changes to the bound on the number of simultaneous labeled policies at boot-time instead of compile-time. This also makes it easier to embed label references in new objects as required for locking/caching with fine-grained network stack locking, such as inpcb structures. This change also moves us further in the direction of hiding the structure of kernel objects from MAC policy modules, not to mention dramatically reducing the number of '&' symbols appearing in both the MAC Framework and MAC policy modules, and improving readability. While this results in minimal performance change with MAC enabled, it will observably shrink the size of a number of critical kernel data structures for the !MAC case, and should have a small (but measurable) performance benefit (i.e., struct vnode, struct socket) do to memory conservation and reduced cost of zeroing memory. NOTE: Users of MAC must recompile their kernel and all MAC modules as a result of this change. Because this is an API change, third party MAC modules will also need to be updated to make less use of the '&' symbol. Suggestions from: bmilekic Obtained from: TrustedBSD Project Sponsored by: DARPA, Network Associates Laboratories
2003-11-12 03:14:31 +00:00
error = label_on_label(cred->cr_label, socketlabel);
return (error ? ENOENT : 0);
}
static int
mac_partition_check_vnode_exec(struct ucred *cred, struct vnode *vp,
struct label *label, struct image_params *imgp, struct label *execlabel)
{
if (execlabel != NULL) {
/*
* We currently don't permit labels to be changed at
* exec-time as part of the partition model, so disallow
* non-NULL partition label changes in execlabel.
*/
if (SLOT(execlabel) != 0)
return (EINVAL);
}
return (0);
}
static struct mac_policy_ops mac_partition_ops =
{
.mpo_init = mac_partition_init,
.mpo_init_cred_label = mac_partition_init_label,
.mpo_destroy_cred_label = mac_partition_destroy_label,
.mpo_copy_cred_label = mac_partition_copy_label,
.mpo_externalize_cred_label = mac_partition_externalize_label,
.mpo_internalize_cred_label = mac_partition_internalize_label,
.mpo_create_proc0 = mac_partition_create_proc0,
.mpo_create_proc1 = mac_partition_create_proc1,
.mpo_relabel_cred = mac_partition_relabel_cred,
.mpo_check_cred_relabel = mac_partition_check_cred_relabel,
.mpo_check_cred_visible = mac_partition_check_cred_visible,
.mpo_check_proc_debug = mac_partition_check_proc_debug,
.mpo_check_proc_sched = mac_partition_check_proc_sched,
.mpo_check_proc_signal = mac_partition_check_proc_signal,
.mpo_check_socket_visible = mac_partition_check_socket_visible,
.mpo_check_vnode_exec = mac_partition_check_vnode_exec,
};
MAC_POLICY_SET(&mac_partition_ops, mac_partition, "TrustedBSD MAC/Partition",
MPC_LOADTIME_FLAG_UNLOADOK, &partition_slot);