/* * AppArmor security module * * This file contains AppArmor policy loading interface function definitions. * * Copyright 2013 Canonical Ltd. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation, version 2 of the * License. * * Fns to provide a checksum of policy that has been loaded this can be * compared to userspace policy compiles to check loaded policy is what * it should be. */#include <crypto/hash.h>#include "include/apparmor.h"#include "include/crypto.h"static unsigned int apparmor_hash_size;static struct crypto_shash *apparmor_tfm;unsigned int aa_hash_size(void){ return apparmor_hash_size;}char *aa_calc_hash(void *data, size_t len){ SHASH_DESC_ON_STACK(desc, apparmor_tfm); char *hash = NULL; int error = -ENOMEM; if (!apparmor_tfm) return NULL; hash = kzalloc(apparmor_hash_size, GFP_KERNEL); if (!hash) goto fail; desc->tfm = apparmor_tfm; desc->flags = 0; error = crypto_shash_init(desc); if (error) goto fail; error = crypto_shash_update(desc, (u8 *) data, len); if (error) goto fail; error = crypto_shash_final(desc, hash); if (error) goto fail; return hash;fail: kfree(hash); return ERR_PTR(error);}int aa_calc_profile_hash(struct aa_profile *profile, u32 version, void *start, size_t len){ SHASH_DESC_ON_STACK(desc, apparmor_tfm); int error = -ENOMEM; __le32 le32_version = cpu_to_le32(version); if (!aa_g_hash_policy) return 0; if (!apparmor_tfm) return 0; profile->hash = kzalloc(apparmor_hash_size, GFP_KERNEL); if (!profile->hash) goto fail; desc->tfm = apparmor_tfm; desc->flags = 0; error = crypto_shash_init(desc); if (error) goto fail; error = crypto_shash_update(desc, (u8 *) &le32_version, 4); if (error) goto fail; error = crypto_shash_update(desc, (u8 *) start, len); if (error) goto fail; error = crypto_shash_final(desc, profile->hash); if (error) goto fail; return 0;fail: kfree(profile->hash); profile->hash = NULL; return error;}static int __init init_profile_hash(void){ struct crypto_shash *tfm; if (!apparmor_initialized) return 0; tfm = crypto_alloc_shash("sha1", 0, CRYPTO_ALG_ASYNC); if (IS_ERR(tfm)) { int error = PTR_ERR(tfm); AA_ERROR("failed to setup profile sha1 hashing: %d\n", error); return error; } apparmor_tfm = tfm; apparmor_hash_size = crypto_shash_digestsize(apparmor_tfm); aa_info_message("AppArmor sha1 policy hashing enabled"); return 0;}late_initcall(init_profile_hash);
/*
* AppArmor security module
*
* This file contains AppArmor policy loading interface function definitions.
*
* Copyright 2013 Canonical Ltd.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation, version 2 of the
* License.
*
* Fns to provide a checksum of policy that has been loaded this can be
* compared to userspace policy compiles to check loaded policy is what
* it should be.
*/
#include <crypto/hash.h>
#include "include/apparmor.h"
#include "include/crypto.h"
static unsigned int apparmor_hash_size;
static struct crypto_shash *apparmor_tfm;
unsigned int aa_hash_size(void)
{
return apparmor_hash_size;
}
char *aa_calc_hash(void *data, size_t len)
{
SHASH_DESC_ON_STACK(desc, apparmor_tfm);
char *hash = NULL;
int error = -ENOMEM;
if (!apparmor_tfm)
return NULL;
hash = kzalloc(apparmor_hash_size, GFP_KERNEL);
if (!hash)
goto fail;
desc->tfm = apparmor_tfm;
desc->flags = 0;
error = crypto_shash_init(desc);
if (error)
goto fail;
error = crypto_shash_update(desc, (u8 *) data, len);
if (error)
goto fail;
error = crypto_shash_final(desc, hash);
if (error)
goto fail;
return hash;
fail:
kfree(hash);
return ERR_PTR(error);
}
int aa_calc_profile_hash(struct aa_profile *profile, u32 version, void *start,
size_t len)
{
SHASH_DESC_ON_STACK(desc, apparmor_tfm);
int error = -ENOMEM;
__le32 le32_version = cpu_to_le32(version);
if (!aa_g_hash_policy)
return 0;
if (!apparmor_tfm)
return 0;
profile->hash = kzalloc(apparmor_hash_size, GFP_KERNEL);
if (!profile->hash)
goto fail;
desc->tfm = apparmor_tfm;
desc->flags = 0;
error = crypto_shash_init(desc);
if (error)
goto fail;
error = crypto_shash_update(desc, (u8 *) &le32_version, 4);
if (error)
goto fail;
error = crypto_shash_update(desc, (u8 *) start, len);
if (error)
goto fail;
error = crypto_shash_final(desc, profile->hash);
if (error)
goto fail;
return 0;
fail:
kfree(profile->hash);
profile->hash = NULL;
return error;
}
static int __init init_profile_hash(void)
{
struct crypto_shash *tfm;
if (!apparmor_initialized)
return 0;
tfm = crypto_alloc_shash("sha1", 0, CRYPTO_ALG_ASYNC);
if (IS_ERR(tfm)) {
int error = PTR_ERR(tfm);
AA_ERROR("failed to setup profile sha1 hashing: %d\n", error);
return error;
}
apparmor_tfm = tfm;
apparmor_hash_size = crypto_shash_digestsize(apparmor_tfm);
aa_info_message("AppArmor sha1 policy hashing enabled");
return 0;
}
late_initcall(init_profile_hash);