1/*
 2 * AppArmor security module
 3 *
 4 * This file contains AppArmor security identifier (secid) manipulation fns
 5 *
 6 * Copyright 2009-2010 Canonical Ltd.
 7 *
 8 * This program is free software; you can redistribute it and/or
 9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation, version 2 of the
11 * License.
12 *
13 *
14 * AppArmor allocates a unique secid for every profile loaded.  If a profile
15 * is replaced it receives the secid of the profile it is replacing.
16 *
17 * The secid value of 0 is invalid.
18 */
19
20#include <linux/spinlock.h>
21#include <linux/errno.h>
22#include <linux/err.h>
 
 
 
 
23
 
 
24#include "include/secid.h"
 
 
25
26/* global counter from which secids are allocated */
27static u32 global_secid;
28static DEFINE_SPINLOCK(secid_lock);
 
 
 
 
 
 
29
30/* TODO FIXME: add secid to profile mapping, and secid recycling */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
31
32/**
33 * aa_alloc_secid - allocate a new secid for a profile
 
 
 
 
 
34 */
35u32 aa_alloc_secid(void)
36{
37	u32 secid;
 
38
39	/*
40	 * TODO FIXME: secid recycling - part of profile mapping table
41	 */
42	spin_lock(&secid_lock);
43	secid = (++global_secid);
44	spin_unlock(&secid_lock);
45	return secid;
 
 
 
 
46}
47
48/**
49 * aa_free_secid - free a secid
50 * @secid: secid to free
51 */
52void aa_free_secid(u32 secid)
53{
54	;			/* NOP ATM */
 
 
 
 
55}

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * AppArmor security module
  4 *
  5 * This file contains AppArmor security identifier (secid) manipulation fns
  6 *
  7 * Copyright 2009-2017 Canonical Ltd.
  8 *
  9 * AppArmor allocates a unique secid for every label used. If a label
 10 * is replaced it receives the secid of the label it is replacing.
 
 
 
 
 
 
 
 
 11 */
 12
 
 13#include <linux/errno.h>
 14#include <linux/err.h>
 15#include <linux/gfp.h>
 16#include <linux/slab.h>
 17#include <linux/spinlock.h>
 18#include <linux/xarray.h>
 19
 20#include "include/cred.h"
 21#include "include/lib.h"
 22#include "include/secid.h"
 23#include "include/label.h"
 24#include "include/policy_ns.h"
 25
 26/*
 27 * secids - do not pin labels with a refcount. They rely on the label
 28 * properly updating/freeing them
 29 */
 30#define AA_FIRST_SECID 2
 31
 32static DEFINE_XARRAY_FLAGS(aa_secids, XA_FLAGS_LOCK_IRQ | XA_FLAGS_TRACK_FREE);
 33
 34int apparmor_display_secid_mode;
 35
 36/*
 37 * TODO: allow policy to reserve a secid range?
 38 * TODO: add secid pinning
 39 * TODO: use secid_update in label replace
 40 */
 41
 42/**
 43 * aa_secid_update - update a secid mapping to a new label
 44 * @secid: secid to update
 45 * @label: label the secid will now map to
 46 */
 47void aa_secid_update(u32 secid, struct aa_label *label)
 48{
 49	unsigned long flags;
 50
 51	xa_lock_irqsave(&aa_secids, flags);
 52	__xa_store(&aa_secids, secid, label, 0);
 53	xa_unlock_irqrestore(&aa_secids, flags);
 54}
 55
 56/*
 57 * see label for inverse aa_label_to_secid
 58 */
 59struct aa_label *aa_secid_to_label(u32 secid)
 60{
 61	return xa_load(&aa_secids, secid);
 62}
 63
 64int apparmor_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
 65{
 66	/* TODO: cache secctx and ref count so we don't have to recreate */
 67	struct aa_label *label = aa_secid_to_label(secid);
 68	int flags = FLAG_VIEW_SUBNS | FLAG_HIDDEN_UNCONFINED | FLAG_ABS_ROOT;
 69	int len;
 70
 71	AA_BUG(!seclen);
 72
 73	if (!label)
 74		return -EINVAL;
 75
 76	if (apparmor_display_secid_mode)
 77		flags |= FLAG_SHOW_MODE;
 78
 79	if (secdata)
 80		len = aa_label_asxprint(secdata, root_ns, label,
 81					flags, GFP_ATOMIC);
 82	else
 83		len = aa_label_snxprint(NULL, 0, root_ns, label, flags);
 84
 85	if (len < 0)
 86		return -ENOMEM;
 87
 88	*seclen = len;
 89
 90	return 0;
 91}
 92
 93int apparmor_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
 94{
 95	struct aa_label *label;
 96
 97	label = aa_label_strn_parse(&root_ns->unconfined->label, secdata,
 98				    seclen, GFP_KERNEL, false, false);
 99	if (IS_ERR(label))
100		return PTR_ERR(label);
101	*secid = label->secid;
102
103	return 0;
104}
105
106void apparmor_release_secctx(char *secdata, u32 seclen)
107{
108	kfree(secdata);
109}
110
111/**
112 * aa_alloc_secid - allocate a new secid for a profile
113 * @label: the label to allocate a secid for
114 * @gfp: memory allocation flags
115 *
116 * Returns: 0 with @label->secid initialized
117 *          <0 returns error with @label->secid set to AA_SECID_INVALID
118 */
119int aa_alloc_secid(struct aa_label *label, gfp_t gfp)
120{
121	unsigned long flags;
122	int ret;
123
124	xa_lock_irqsave(&aa_secids, flags);
125	ret = __xa_alloc(&aa_secids, &label->secid, label,
126			XA_LIMIT(AA_FIRST_SECID, INT_MAX), gfp);
127	xa_unlock_irqrestore(&aa_secids, flags);
128
129	if (ret < 0) {
130		label->secid = AA_SECID_INVALID;
131		return ret;
132	}
133
134	return 0;
135}
136
137/**
138 * aa_free_secid - free a secid
139 * @secid: secid to free
140 */
141void aa_free_secid(u32 secid)
142{
143	unsigned long flags;
144
145	xa_lock_irqsave(&aa_secids, flags);
146	__xa_erase(&aa_secids, secid);
147	xa_unlock_irqrestore(&aa_secids, flags);
148}