iint.c

 1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 * Copyright (C) 2008 IBM Corporation
 4 *
 5 * Authors:
 6 * Mimi Zohar <zohar@us.ibm.com>
 7 *
 8 * File: integrity_iint.c
 9 *	- initialize the integrity directory in securityfs
10 *	- load IMA and EVM keys
11 */
12#include <linux/security.h>
13#include "integrity.h"
14
15struct dentry *integrity_dir;
16
17/*
18 * integrity_kernel_read - read data from the file
19 *
20 * This is a function for reading file content instead of kernel_read().
21 * It does not perform locking checks to ensure it cannot be blocked.
22 * It does not perform security checks because it is irrelevant for IMA.
23 *
24 */
25int integrity_kernel_read(struct file *file, loff_t offset,
26			  void *addr, unsigned long count)
27{
28	return __kernel_read(file, addr, count, &offset);
29}
30
31/*
32 * integrity_load_keys - load integrity keys hook
33 *
34 * Hooks is called from init/main.c:kernel_init_freeable()
35 * when rootfs is ready
36 */
37void __init integrity_load_keys(void)
38{
39	ima_load_x509();
40
41	if (!IS_ENABLED(CONFIG_IMA_LOAD_X509))
42		evm_load_x509();
43}
44
45int __init integrity_fs_init(void)
46{
47	if (integrity_dir)
48		return 0;
49
50	integrity_dir = securityfs_create_dir("integrity", NULL);
51	if (IS_ERR(integrity_dir)) {
52		int ret = PTR_ERR(integrity_dir);
53
54		if (ret != -ENODEV)
55			pr_err("Unable to create integrity sysfs dir: %d\n",
56			       ret);
57		integrity_dir = NULL;
58		return ret;
59	}
60
61	return 0;
62}
63
64void __init integrity_fs_fini(void)
65{
66	if (!integrity_dir || !simple_empty(integrity_dir))
67		return;
68
69	securityfs_remove(integrity_dir);
70	integrity_dir = NULL;
71}