apparmor: add support for mapping secids and using secctxes
Use a radix tree to provide a map between the secid and the label, and along with it a basic ability to provide secctx conversion. Shared/cached secctx will be added later. Signed-off-by: John Johansen <john.johansen@canonical.com>
This commit is contained in:
John Johansen
Родитель
552c69b36e
Коммит
c092921219
|
|
@ -281,7 +281,7 @@ void __aa_labelset_update_subtree(struct aa_ns *ns);
|
|||
|
||||
void aa_label_free(struct aa_label *label);
|
||||
void aa_label_kref(struct kref *kref);
|
||||
bool aa_label_init(struct aa_label *label, int size);
|
||||
bool aa_label_init(struct aa_label *label, int size, gfp_t gfp);
|
||||
struct aa_label *aa_label_alloc(int size, struct aa_proxy *proxy, gfp_t gfp);
|
||||
|
||||
bool aa_label_is_subset(struct aa_label *set, struct aa_label *sub);
|
||||
|
|
|
|||
|
|
@ -3,7 +3,7 @@
|
|||
*
|
||||
* This file contains AppArmor security identifier (secid) definitions
|
||||
*
|
||||
* Copyright 2009-2010 Canonical Ltd.
|
||||
* Copyright 2009-2018 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
|
||||
|
|
@ -14,13 +14,22 @@
|
|||
#ifndef __AA_SECID_H
|
||||
#define __AA_SECID_H
|
||||
|
||||
#include <linux/slab.h>
|
||||
#include <linux/types.h>
|
||||
|
||||
struct aa_label;
|
||||
|
||||
/* secid value that will not be allocated */
|
||||
#define AA_SECID_INVALID 0
|
||||
#define AA_SECID_ALLOC AA_SECID_INVALID
|
||||
|
||||
u32 aa_alloc_secid(void);
|
||||
struct aa_label *aa_secid_to_label(u32 secid);
|
||||
int apparmor_secid_to_secctx(u32 secid, char **secdata, u32 *seclen);
|
||||
int apparmor_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid);
|
||||
void apparmor_release_secctx(char *secdata, u32 seclen);
|
||||
|
||||
|
||||
u32 aa_alloc_secid(struct aa_label *label, gfp_t gfp);
|
||||
void aa_free_secid(u32 secid);
|
||||
void aa_secid_update(u32 secid, struct aa_label *label);
|
||||
|
||||
#endif /* __AA_SECID_H */
|
||||
|
|
|
|||
|
|
@ -402,12 +402,12 @@ static void label_free_or_put_new(struct aa_label *label, struct aa_label *new)
|
|||
aa_put_label(new);
|
||||
}
|
||||
|
||||
bool aa_label_init(struct aa_label *label, int size)
|
||||
bool aa_label_init(struct aa_label *label, int size, gfp_t gfp)
|
||||
{
|
||||
AA_BUG(!label);
|
||||
AA_BUG(size < 1);
|
||||
|
||||
label->secid = aa_alloc_secid();
|
||||
label->secid = aa_alloc_secid(label, gfp);
|
||||
if (label->secid == AA_SECID_INVALID)
|
||||
return false;
|
||||
|
||||
|
|
@ -441,7 +441,7 @@ struct aa_label *aa_label_alloc(int size, struct aa_proxy *proxy, gfp_t gfp)
|
|||
if (!new)
|
||||
goto fail;
|
||||
|
||||
if (!aa_label_init(new, size))
|
||||
if (!aa_label_init(new, size, gfp))
|
||||
goto fail;
|
||||
|
||||
if (!proxy) {
|
||||
|
|
|
|||
|
|
@ -39,6 +39,7 @@
|
|||
#include "include/policy_ns.h"
|
||||
#include "include/procattr.h"
|
||||
#include "include/mount.h"
|
||||
#include "include/secid.h"
|
||||
|
||||
/* Flag indicating whether initialization completed */
|
||||
int apparmor_initialized;
|
||||
|
|
@ -1188,6 +1189,10 @@ static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
|
|||
LSM_HOOK_INIT(task_alloc, apparmor_task_alloc),
|
||||
LSM_HOOK_INIT(task_setrlimit, apparmor_task_setrlimit),
|
||||
LSM_HOOK_INIT(task_kill, apparmor_task_kill),
|
||||
|
||||
LSM_HOOK_INIT(secid_to_secctx, apparmor_secid_to_secctx),
|
||||
LSM_HOOK_INIT(secctx_to_secid, apparmor_secctx_to_secid),
|
||||
LSM_HOOK_INIT(release_secctx, apparmor_release_secctx),
|
||||
};
|
||||
|
||||
/*
|
||||
|
|
|
|||
|
|
@ -268,7 +268,7 @@ struct aa_profile *aa_alloc_profile(const char *hname, struct aa_proxy *proxy,
|
|||
|
||||
if (!aa_policy_init(&profile->base, NULL, hname, gfp))
|
||||
goto fail;
|
||||
if (!aa_label_init(&profile->label, 1))
|
||||
if (!aa_label_init(&profile->label, 1, gfp))
|
||||
goto fail;
|
||||
|
||||
/* update being set needed by fs interface */
|
||||
|
|
|
|||
|
|
@ -3,7 +3,7 @@
|
|||
*
|
||||
* This file contains AppArmor security identifier (secid) manipulation fns
|
||||
*
|
||||
* Copyright 2009-2010 Canonical Ltd.
|
||||
* Copyright 2009-2017 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
|
||||
|
|
@ -11,37 +11,218 @@
|
|||
* License.
|
||||
*
|
||||
*
|
||||
* AppArmor allocates a unique secid for every profile loaded. If a profile
|
||||
* is replaced it receives the secid of the profile it is replacing.
|
||||
*
|
||||
* The secid value of 0 is invalid.
|
||||
* AppArmor allocates a unique secid for every label used. If a label
|
||||
* is replaced it receives the secid of the label it is replacing.
|
||||
*/
|
||||
|
||||
#include <linux/spinlock.h>
|
||||
#include <linux/errno.h>
|
||||
#include <linux/err.h>
|
||||
#include <linux/gfp.h>
|
||||
#include <linux/slab.h>
|
||||
#include <linux/spinlock.h>
|
||||
|
||||
#include "include/cred.h"
|
||||
#include "include/lib.h"
|
||||
#include "include/secid.h"
|
||||
#include "include/label.h"
|
||||
#include "include/policy_ns.h"
|
||||
|
||||
/* global counter from which secids are allocated */
|
||||
static u32 global_secid;
|
||||
/*
|
||||
* secids - do not pin labels with a refcount. They rely on the label
|
||||
* properly updating/freeing them
|
||||
*
|
||||
* A singly linked free list is used to track secids that have been
|
||||
* freed and reuse them before allocating new ones
|
||||
*/
|
||||
|
||||
#define FREE_LIST_HEAD 1
|
||||
|
||||
static RADIX_TREE(aa_secids_map, GFP_ATOMIC);
|
||||
static DEFINE_SPINLOCK(secid_lock);
|
||||
static u32 alloced_secid = FREE_LIST_HEAD;
|
||||
static u32 free_list = FREE_LIST_HEAD;
|
||||
static unsigned long free_count;
|
||||
|
||||
/*
|
||||
* TODO: allow policy to reserve a secid range?
|
||||
* TODO: add secid pinning
|
||||
* TODO: use secid_update in label replace
|
||||
*/
|
||||
|
||||
#define SECID_MAX U32_MAX
|
||||
|
||||
/* TODO: mark free list as exceptional */
|
||||
static void *to_ptr(u32 secid)
|
||||
{
|
||||
return (void *)
|
||||
((((unsigned long) secid) << RADIX_TREE_EXCEPTIONAL_SHIFT));
|
||||
}
|
||||
|
||||
static u32 to_secid(void *ptr)
|
||||
{
|
||||
return (u32) (((unsigned long) ptr) >> RADIX_TREE_EXCEPTIONAL_SHIFT);
|
||||
}
|
||||
|
||||
|
||||
/* TODO: tag free_list entries to mark them as different */
|
||||
static u32 __pop(struct aa_label *label)
|
||||
{
|
||||
u32 secid = free_list;
|
||||
void __rcu **slot;
|
||||
void *entry;
|
||||
|
||||
if (free_list == FREE_LIST_HEAD)
|
||||
return AA_SECID_INVALID;
|
||||
|
||||
slot = radix_tree_lookup_slot(&aa_secids_map, secid);
|
||||
AA_BUG(!slot);
|
||||
entry = radix_tree_deref_slot_protected(slot, &secid_lock);
|
||||
free_list = to_secid(entry);
|
||||
radix_tree_replace_slot(&aa_secids_map, slot, label);
|
||||
free_count--;
|
||||
|
||||
return secid;
|
||||
}
|
||||
|
||||
static void __push(u32 secid)
|
||||
{
|
||||
void __rcu **slot;
|
||||
|
||||
slot = radix_tree_lookup_slot(&aa_secids_map, secid);
|
||||
AA_BUG(!slot);
|
||||
radix_tree_replace_slot(&aa_secids_map, slot, to_ptr(free_list));
|
||||
free_list = secid;
|
||||
free_count++;
|
||||
}
|
||||
|
||||
static struct aa_label * __secid_update(u32 secid, struct aa_label *label)
|
||||
{
|
||||
struct aa_label *old;
|
||||
void __rcu **slot;
|
||||
|
||||
slot = radix_tree_lookup_slot(&aa_secids_map, secid);
|
||||
AA_BUG(!slot);
|
||||
old = radix_tree_deref_slot_protected(slot, &secid_lock);
|
||||
radix_tree_replace_slot(&aa_secids_map, slot, label);
|
||||
|
||||
return old;
|
||||
}
|
||||
|
||||
/**
|
||||
* aa_secid_update - update a secid mapping to a new label
|
||||
* @secid: secid to update
|
||||
* @label: label the secid will now map to
|
||||
*/
|
||||
void aa_secid_update(u32 secid, struct aa_label *label)
|
||||
{
|
||||
struct aa_label *old;
|
||||
unsigned long flags;
|
||||
|
||||
spin_lock_irqsave(&secid_lock, flags);
|
||||
old = __secid_update(secid, label);
|
||||
spin_unlock_irqrestore(&secid_lock, flags);
|
||||
}
|
||||
|
||||
/**
|
||||
*
|
||||
* see label for inverse aa_label_to_secid
|
||||
*/
|
||||
struct aa_label *aa_secid_to_label(u32 secid)
|
||||
{
|
||||
struct aa_label *label;
|
||||
|
||||
rcu_read_lock();
|
||||
label = radix_tree_lookup(&aa_secids_map, secid);
|
||||
rcu_read_unlock();
|
||||
|
||||
return label;
|
||||
}
|
||||
|
||||
int apparmor_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
|
||||
{
|
||||
/* TODO: cache secctx and ref count so we don't have to recreate */
|
||||
struct aa_label *label = aa_secid_to_label(secid);
|
||||
|
||||
AA_BUG(!secdata);
|
||||
AA_BUG(!seclen);
|
||||
|
||||
if (!label)
|
||||
return -EINVAL;
|
||||
|
||||
if (secdata)
|
||||
*seclen = aa_label_asxprint(secdata, root_ns, label,
|
||||
FLAG_SHOW_MODE | FLAG_VIEW_SUBNS |
|
||||
FLAG_HIDDEN_UNCONFINED |
|
||||
FLAG_ABS_ROOT, GFP_ATOMIC);
|
||||
else
|
||||
*seclen = aa_label_snxprint(NULL, 0, root_ns, label,
|
||||
FLAG_SHOW_MODE | FLAG_VIEW_SUBNS |
|
||||
FLAG_HIDDEN_UNCONFINED |
|
||||
FLAG_ABS_ROOT);
|
||||
if (*seclen < 0)
|
||||
return -ENOMEM;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
|
||||
int apparmor_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
|
||||
{
|
||||
struct aa_label *label;
|
||||
|
||||
label = aa_label_strn_parse(&root_ns->unconfined->label, secdata,
|
||||
seclen, GFP_KERNEL, false, false);
|
||||
if (IS_ERR(label))
|
||||
return PTR_ERR(label);
|
||||
*secid = label->secid;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
void apparmor_release_secctx(char *secdata, u32 seclen)
|
||||
{
|
||||
kfree(secdata);
|
||||
}
|
||||
|
||||
/* TODO FIXME: add secid to profile mapping, and secid recycling */
|
||||
|
||||
/**
|
||||
* aa_alloc_secid - allocate a new secid for a profile
|
||||
*/
|
||||
u32 aa_alloc_secid(void)
|
||||
u32 aa_alloc_secid(struct aa_label *label, gfp_t gfp)
|
||||
{
|
||||
unsigned long flags;
|
||||
u32 secid;
|
||||
|
||||
/*
|
||||
* TODO FIXME: secid recycling - part of profile mapping table
|
||||
*/
|
||||
spin_lock(&secid_lock);
|
||||
secid = (++global_secid);
|
||||
spin_unlock(&secid_lock);
|
||||
/* racey, but at worst causes new allocation instead of reuse */
|
||||
if (free_list == FREE_LIST_HEAD) {
|
||||
bool preload = 0;
|
||||
int res;
|
||||
|
||||
retry:
|
||||
if (gfpflags_allow_blocking(gfp) && !radix_tree_preload(gfp))
|
||||
preload = 1;
|
||||
spin_lock_irqsave(&secid_lock, flags);
|
||||
if (alloced_secid != SECID_MAX) {
|
||||
secid = ++alloced_secid;
|
||||
res = radix_tree_insert(&aa_secids_map, secid, label);
|
||||
AA_BUG(res == -EEXIST);
|
||||
} else {
|
||||
secid = AA_SECID_INVALID;
|
||||
}
|
||||
spin_unlock_irqrestore(&secid_lock, flags);
|
||||
if (preload)
|
||||
radix_tree_preload_end();
|
||||
} else {
|
||||
spin_lock_irqsave(&secid_lock, flags);
|
||||
/* remove entry from free list */
|
||||
secid = __pop(label);
|
||||
if (secid == AA_SECID_INVALID) {
|
||||
spin_unlock_irqrestore(&secid_lock, flags);
|
||||
goto retry;
|
||||
}
|
||||
spin_unlock_irqrestore(&secid_lock, flags);
|
||||
}
|
||||
|
||||
return secid;
|
||||
}
|
||||
|
||||
|
|
@ -51,5 +232,9 @@ u32 aa_alloc_secid(void)
|
|||
*/
|
||||
void aa_free_secid(u32 secid)
|
||||
{
|
||||
; /* NOP ATM */
|
||||
unsigned long flags;
|
||||
|
||||
spin_lock_irqsave(&secid_lock, flags);
|
||||
__push(secid);
|
||||
spin_unlock_irqrestore(&secid_lock, flags);
|
||||
}
|
||||
|
|
|
|||
Загрузка…
Ссылка в новой задаче