linux_dsm_epyc7002/security/apparmor/include/cred.h
Casey Schaufler bbd3662a83 Infrastructure management of the cred security blob
Move management of the cred security blob out of the
security modules and into the security infrastructre.
Instead of allocating and freeing space the security
modules tell the infrastructure how much space they
require.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
[kees: adjusted for ordered init series]
Signed-off-by: Kees Cook <keescook@chromium.org>
2019-01-08 13:18:44 -08:00

193 lines
4.9 KiB
C

/*
* AppArmor security module
*
* This file contains AppArmor contexts used to associate "labels" to objects.
*
* Copyright (C) 1998-2008 Novell/SUSE
* Copyright 2009-2010 Canonical Ltd.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation, version 2 of the
* License.
*/
#ifndef __AA_CONTEXT_H
#define __AA_CONTEXT_H
#include <linux/cred.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include "label.h"
#include "policy_ns.h"
#include "task.h"
static inline struct aa_label *cred_label(const struct cred *cred)
{
struct aa_label **blob = cred->security + apparmor_blob_sizes.lbs_cred;
AA_BUG(!blob);
return *blob;
}
static inline void set_cred_label(const struct cred *cred,
struct aa_label *label)
{
struct aa_label **blob = cred->security + apparmor_blob_sizes.lbs_cred;
AA_BUG(!blob);
*blob = label;
}
/**
* aa_cred_raw_label - obtain cred's label
* @cred: cred to obtain label from (NOT NULL)
*
* Returns: confining label
*
* does NOT increment reference count
*/
static inline struct aa_label *aa_cred_raw_label(const struct cred *cred)
{
struct aa_label *label = cred_label(cred);
AA_BUG(!label);
return label;
}
/**
* aa_get_newest_cred_label - obtain the newest label on a cred
* @cred: cred to obtain label from (NOT NULL)
*
* Returns: newest version of confining label
*/
static inline struct aa_label *aa_get_newest_cred_label(const struct cred *cred)
{
return aa_get_newest_label(aa_cred_raw_label(cred));
}
/**
* __aa_task_raw_label - retrieve another task's label
* @task: task to query (NOT NULL)
*
* Returns: @task's label without incrementing its ref count
*
* If @task != current needs to be called in RCU safe critical section
*/
static inline struct aa_label *__aa_task_raw_label(struct task_struct *task)
{
return aa_cred_raw_label(__task_cred(task));
}
/**
* aa_current_raw_label - find the current tasks confining label
*
* Returns: up to date confining label or the ns unconfined label (NOT NULL)
*
* This fn will not update the tasks cred to the most up to date version
* of the label so it is safe to call when inside of locks.
*/
static inline struct aa_label *aa_current_raw_label(void)
{
return aa_cred_raw_label(current_cred());
}
/**
* aa_get_current_label - get the newest version of the current tasks label
*
* Returns: newest version of confining label (NOT NULL)
*
* This fn will not update the tasks cred, so it is safe inside of locks
*
* The returned reference must be put with aa_put_label()
*/
static inline struct aa_label *aa_get_current_label(void)
{
struct aa_label *l = aa_current_raw_label();
if (label_is_stale(l))
return aa_get_newest_label(l);
return aa_get_label(l);
}
#define __end_current_label_crit_section(X) end_current_label_crit_section(X)
/**
* end_label_crit_section - put a reference found with begin_current_label..
* @label: label reference to put
*
* Should only be used with a reference obtained with
* begin_current_label_crit_section and never used in situations where the
* task cred may be updated
*/
static inline void end_current_label_crit_section(struct aa_label *label)
{
if (label != aa_current_raw_label())
aa_put_label(label);
}
/**
* __begin_current_label_crit_section - current's confining label
*
* Returns: up to date confining label or the ns unconfined label (NOT NULL)
*
* safe to call inside locks
*
* The returned reference must be put with __end_current_label_crit_section()
* This must NOT be used if the task cred could be updated within the
* critical section between __begin_current_label_crit_section() ..
* __end_current_label_crit_section()
*/
static inline struct aa_label *__begin_current_label_crit_section(void)
{
struct aa_label *label = aa_current_raw_label();
if (label_is_stale(label))
label = aa_get_newest_label(label);
return label;
}
/**
* begin_current_label_crit_section - current's confining label and update it
*
* Returns: up to date confining label or the ns unconfined label (NOT NULL)
*
* Not safe to call inside locks
*
* The returned reference must be put with end_current_label_crit_section()
* This must NOT be used if the task cred could be updated within the
* critical section between begin_current_label_crit_section() ..
* end_current_label_crit_section()
*/
static inline struct aa_label *begin_current_label_crit_section(void)
{
struct aa_label *label = aa_current_raw_label();
might_sleep();
if (label_is_stale(label)) {
label = aa_get_newest_label(label);
if (aa_replace_current_label(label) == 0)
/* task cred will keep the reference */
aa_put_label(label);
}
return label;
}
static inline struct aa_ns *aa_get_current_ns(void)
{
struct aa_label *label;
struct aa_ns *ns;
label = __begin_current_label_crit_section();
ns = aa_get_ns(labels_ns(label));
__end_current_label_crit_section(label);
return ns;
}
#endif /* __AA_CONTEXT_H */