aboutsummaryrefslogtreecommitdiff
path: root/security/landlock/cred.c
blob: ec6c37f04a1919b82c7dc7590d3615697568df4c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Landlock LSM - Credential hooks
 *
 * Copyright © 2017-2020 Mickaël Salaün <mic@digikod.net>
 * Copyright © 2018-2020 ANSSI
 */

#include <linux/cred.h>
#include <linux/lsm_hooks.h>

#include "common.h"
#include "cred.h"
#include "ruleset.h"
#include "setup.h"

static int hook_cred_prepare(struct cred *const new,
			     const struct cred *const old, const gfp_t gfp)
{
	struct landlock_ruleset *const old_dom = landlock_cred(old)->domain;

	if (old_dom) {
		landlock_get_ruleset(old_dom);
		landlock_cred(new)->domain = old_dom;
	}
	return 0;
}

static void hook_cred_free(struct cred *const cred)
{
	struct landlock_ruleset *const dom = landlock_cred(cred)->domain;

	if (dom)
		landlock_put_ruleset_deferred(dom);
}

static struct security_hook_list landlock_hooks[] __lsm_ro_after_init = {
	LSM_HOOK_INIT(cred_prepare, hook_cred_prepare),
	LSM_HOOK_INIT(cred_free, hook_cred_free),
};

__init void landlock_add_cred_hooks(void)
{
	security_add_hooks(landlock_hooks, ARRAY_SIZE(landlock_hooks),
			   LANDLOCK_NAME);
}