2 * AppArmor security module
4 * This file contains AppArmor policy loading interface function definitions.
6 * Copyright 2013 Canonical Ltd.
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
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
18 #include <crypto/hash.h>
20 #include "include/apparmor.h"
21 #include "include/crypto.h"
23 static unsigned int apparmor_hash_size;
25 static struct crypto_shash *apparmor_tfm;
27 unsigned int aa_hash_size(void)
29 return apparmor_hash_size;
32 char *aa_calc_hash(void *data, size_t len)
35 struct shash_desc shash;
36 char ctx[crypto_shash_descsize(apparmor_tfm)];
44 hash = kzalloc(apparmor_hash_size, GFP_KERNEL);
48 desc.shash.tfm = apparmor_tfm;
51 error = crypto_shash_init(&desc.shash);
54 error = crypto_shash_update(&desc.shash, (u8 *) data, len);
57 error = crypto_shash_final(&desc.shash, hash);
66 return ERR_PTR(error);
69 int aa_calc_profile_hash(struct aa_profile *profile, u32 version, void *start,
73 struct shash_desc shash;
74 char ctx[crypto_shash_descsize(apparmor_tfm)];
77 __le32 le32_version = cpu_to_le32(version);
79 if (!aa_g_hash_policy)
85 profile->hash = kzalloc(apparmor_hash_size, GFP_KERNEL);
89 desc.shash.tfm = apparmor_tfm;
92 error = crypto_shash_init(&desc.shash);
95 error = crypto_shash_update(&desc.shash, (u8 *) &le32_version, 4);
98 error = crypto_shash_update(&desc.shash, (u8 *) start, len);
101 error = crypto_shash_final(&desc.shash, profile->hash);
108 kfree(profile->hash);
109 profile->hash = NULL;
114 static int __init init_profile_hash(void)
116 struct crypto_shash *tfm;
118 if (!apparmor_initialized)
121 tfm = crypto_alloc_shash("sha1", 0, CRYPTO_ALG_ASYNC);
123 int error = PTR_ERR(tfm);
124 AA_ERROR("failed to setup profile sha1 hashing: %d\n", error);
128 apparmor_hash_size = crypto_shash_digestsize(apparmor_tfm);
130 aa_info_message("AppArmor sha1 policy hashing enabled");
135 late_initcall(init_profile_hash);