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1/*
2 * AppArmor security module
3 *
4 * This file contains AppArmor policy loading interface function definitions.
5 *
6 * Copyright 2013 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 * Fns to provide a checksum of policy that has been loaded this can be
14 * compared to userspace policy compiles to check loaded policy is what
15 * it should be.
16 */
17
18#include <crypto/hash.h>
19
20#include "include/apparmor.h"
21#include "include/crypto.h"
22
23static unsigned int apparmor_hash_size;
24
25static struct crypto_shash *apparmor_tfm;
26
27unsigned int aa_hash_size(void)
28{
29 return apparmor_hash_size;
30}
31
32int aa_calc_profile_hash(struct aa_profile *profile, u32 version, void *start,
33 size_t len)
34{
35 struct {
36 struct shash_desc shash;
37 char ctx[crypto_shash_descsize(apparmor_tfm)];
38 } desc;
39 int error = -ENOMEM;
40 u32 le32_version = cpu_to_le32(version);
41
42 if (!apparmor_tfm)
43 return 0;
44
45 profile->hash = kzalloc(apparmor_hash_size, GFP_KERNEL);
46 if (!profile->hash)
47 goto fail;
48
49 desc.shash.tfm = apparmor_tfm;
50 desc.shash.flags = 0;
51
52 error = crypto_shash_init(&desc.shash);
53 if (error)
54 goto fail;
55 error = crypto_shash_update(&desc.shash, (u8 *) &le32_version, 4);
56 if (error)
57 goto fail;
58 error = crypto_shash_update(&desc.shash, (u8 *) start, len);
59 if (error)
60 goto fail;
61 error = crypto_shash_final(&desc.shash, profile->hash);
62 if (error)
63 goto fail;
64
65 return 0;
66
67fail:
68 kfree(profile->hash);
69 profile->hash = NULL;
70
71 return error;
72}
73
74static int __init init_profile_hash(void)
75{
76 struct crypto_shash *tfm;
77
78 if (!apparmor_initialized)
79 return 0;
80
81 tfm = crypto_alloc_shash("sha1", 0, CRYPTO_ALG_ASYNC);
82 if (IS_ERR(tfm)) {
83 int error = PTR_ERR(tfm);
84 AA_ERROR("failed to setup profile sha1 hashing: %d\n", error);
85 return error;
86 }
87 apparmor_tfm = tfm;
88 apparmor_hash_size = crypto_shash_digestsize(apparmor_tfm);
89
90 aa_info_message("AppArmor sha1 policy hashing enabled");
91
92 return 0;
93}
94
95late_initcall(init_profile_hash);
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * AppArmor security module
4 *
5 * This file contains AppArmor policy loading interface function definitions.
6 *
7 * Copyright 2013 Canonical Ltd.
8 *
9 * Fns to provide a checksum of policy that has been loaded this can be
10 * compared to userspace policy compiles to check loaded policy is what
11 * it should be.
12 */
13
14#include <crypto/hash.h>
15
16#include "include/apparmor.h"
17#include "include/crypto.h"
18
19static unsigned int apparmor_hash_size;
20
21static struct crypto_shash *apparmor_tfm;
22
23unsigned int aa_hash_size(void)
24{
25 return apparmor_hash_size;
26}
27
28char *aa_calc_hash(void *data, size_t len)
29{
30 SHASH_DESC_ON_STACK(desc, apparmor_tfm);
31 char *hash = NULL;
32 int error = -ENOMEM;
33
34 if (!apparmor_tfm)
35 return NULL;
36
37 hash = kzalloc(apparmor_hash_size, GFP_KERNEL);
38 if (!hash)
39 goto fail;
40
41 desc->tfm = apparmor_tfm;
42
43 error = crypto_shash_init(desc);
44 if (error)
45 goto fail;
46 error = crypto_shash_update(desc, (u8 *) data, len);
47 if (error)
48 goto fail;
49 error = crypto_shash_final(desc, hash);
50 if (error)
51 goto fail;
52
53 return hash;
54
55fail:
56 kfree(hash);
57
58 return ERR_PTR(error);
59}
60
61int aa_calc_profile_hash(struct aa_profile *profile, u32 version, void *start,
62 size_t len)
63{
64 SHASH_DESC_ON_STACK(desc, apparmor_tfm);
65 int error = -ENOMEM;
66 __le32 le32_version = cpu_to_le32(version);
67
68 if (!aa_g_hash_policy)
69 return 0;
70
71 if (!apparmor_tfm)
72 return 0;
73
74 profile->hash = kzalloc(apparmor_hash_size, GFP_KERNEL);
75 if (!profile->hash)
76 goto fail;
77
78 desc->tfm = apparmor_tfm;
79
80 error = crypto_shash_init(desc);
81 if (error)
82 goto fail;
83 error = crypto_shash_update(desc, (u8 *) &le32_version, 4);
84 if (error)
85 goto fail;
86 error = crypto_shash_update(desc, (u8 *) start, len);
87 if (error)
88 goto fail;
89 error = crypto_shash_final(desc, profile->hash);
90 if (error)
91 goto fail;
92
93 return 0;
94
95fail:
96 kfree(profile->hash);
97 profile->hash = NULL;
98
99 return error;
100}
101
102static int __init init_profile_hash(void)
103{
104 struct crypto_shash *tfm;
105
106 if (!apparmor_initialized)
107 return 0;
108
109 tfm = crypto_alloc_shash("sha1", 0, 0);
110 if (IS_ERR(tfm)) {
111 int error = PTR_ERR(tfm);
112 AA_ERROR("failed to setup profile sha1 hashing: %d\n", error);
113 return error;
114 }
115 apparmor_tfm = tfm;
116 apparmor_hash_size = crypto_shash_digestsize(apparmor_tfm);
117
118 aa_info_message("AppArmor sha1 policy hashing enabled");
119
120 return 0;
121}
122
123late_initcall(init_profile_hash);