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)
34 SHASH_DESC_ON_STACK(desc, apparmor_tfm);
41 hash = kzalloc(apparmor_hash_size, GFP_KERNEL);
45 desc->tfm = apparmor_tfm;
47 error = crypto_shash_init(desc);
50 error = crypto_shash_update(desc, (u8 *) data, len);
53 error = crypto_shash_final(desc, hash);
62 return ERR_PTR(error);
65 int aa_calc_profile_hash(struct aa_profile *profile, u32 version, void *start,
68 SHASH_DESC_ON_STACK(desc, apparmor_tfm);
70 __le32 le32_version = cpu_to_le32(version);
72 if (!aa_g_hash_policy)
78 profile->hash = kzalloc(apparmor_hash_size, GFP_KERNEL);
82 desc->tfm = apparmor_tfm;
84 error = crypto_shash_init(desc);
87 error = crypto_shash_update(desc, (u8 *) &le32_version, 4);
90 error = crypto_shash_update(desc, (u8 *) start, len);
93 error = crypto_shash_final(desc, profile->hash);
100 kfree(profile->hash);
101 profile->hash = NULL;
106 static int __init init_profile_hash(void)
108 struct crypto_shash *tfm;
110 if (!apparmor_initialized)
113 tfm = crypto_alloc_shash("sha1", 0, 0);
115 int error = PTR_ERR(tfm);
116 AA_ERROR("failed to setup profile sha1 hashing: %d\n", error);
120 apparmor_hash_size = crypto_shash_digestsize(apparmor_tfm);
122 aa_info_message("AppArmor sha1 policy hashing enabled");
127 late_initcall(init_profile_hash);