linux/security/ipe/ipe.c
Deven Bowers ba199dc909 scripts: add boot policy generation program
Enables an IPE policy to be enforced from kernel start, enabling access
control based on trust from kernel startup. This is accomplished by
transforming an IPE policy indicated by CONFIG_IPE_BOOT_POLICY into a
c-string literal that is parsed at kernel startup as an unsigned policy.

Signed-off-by: Deven Bowers <deven.desai@linux.microsoft.com>
Signed-off-by: Fan Wu <wufan@linux.microsoft.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2024-08-20 14:03:39 -04:00

100 lines
2.6 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2020-2024 Microsoft Corporation. All rights reserved.
*/
#include <uapi/linux/lsm.h>
#include "ipe.h"
#include "eval.h"
#include "hooks.h"
#include "eval.h"
extern const char *const ipe_boot_policy;
bool ipe_enabled;
static struct lsm_blob_sizes ipe_blobs __ro_after_init = {
.lbs_superblock = sizeof(struct ipe_superblock),
#ifdef CONFIG_IPE_PROP_DM_VERITY
.lbs_bdev = sizeof(struct ipe_bdev),
#endif /* CONFIG_IPE_PROP_DM_VERITY */
#ifdef CONFIG_IPE_PROP_FS_VERITY_BUILTIN_SIG
.lbs_inode = sizeof(struct ipe_inode),
#endif /* CONFIG_IPE_PROP_FS_VERITY_BUILTIN_SIG */
};
static const struct lsm_id ipe_lsmid = {
.name = "ipe",
.id = LSM_ID_IPE,
};
struct ipe_superblock *ipe_sb(const struct super_block *sb)
{
return sb->s_security + ipe_blobs.lbs_superblock;
}
#ifdef CONFIG_IPE_PROP_DM_VERITY
struct ipe_bdev *ipe_bdev(struct block_device *b)
{
return b->bd_security + ipe_blobs.lbs_bdev;
}
#endif /* CONFIG_IPE_PROP_DM_VERITY */
#ifdef CONFIG_IPE_PROP_FS_VERITY_BUILTIN_SIG
struct ipe_inode *ipe_inode(const struct inode *inode)
{
return inode->i_security + ipe_blobs.lbs_inode;
}
#endif /* CONFIG_IPE_PROP_FS_VERITY_BUILTIN_SIG */
static struct security_hook_list ipe_hooks[] __ro_after_init = {
LSM_HOOK_INIT(bprm_check_security, ipe_bprm_check_security),
LSM_HOOK_INIT(mmap_file, ipe_mmap_file),
LSM_HOOK_INIT(file_mprotect, ipe_file_mprotect),
LSM_HOOK_INIT(kernel_read_file, ipe_kernel_read_file),
LSM_HOOK_INIT(kernel_load_data, ipe_kernel_load_data),
LSM_HOOK_INIT(initramfs_populated, ipe_unpack_initramfs),
#ifdef CONFIG_IPE_PROP_DM_VERITY
LSM_HOOK_INIT(bdev_free_security, ipe_bdev_free_security),
LSM_HOOK_INIT(bdev_setintegrity, ipe_bdev_setintegrity),
#endif /* CONFIG_IPE_PROP_DM_VERITY */
#ifdef CONFIG_IPE_PROP_FS_VERITY_BUILTIN_SIG
LSM_HOOK_INIT(inode_setintegrity, ipe_inode_setintegrity),
#endif /* CONFIG_IPE_PROP_FS_VERITY_BUILTIN_SIG */
};
/**
* ipe_init() - Entry point of IPE.
*
* This is called at LSM init, which happens occurs early during kernel
* start up. During this phase, IPE registers its hooks and loads the
* builtin boot policy.
*
* Return:
* * %0 - OK
* * %-ENOMEM - Out of memory (OOM)
*/
static int __init ipe_init(void)
{
struct ipe_policy *p = NULL;
security_add_hooks(ipe_hooks, ARRAY_SIZE(ipe_hooks), &ipe_lsmid);
ipe_enabled = true;
if (ipe_boot_policy) {
p = ipe_new_policy(ipe_boot_policy, strlen(ipe_boot_policy),
NULL, 0);
if (IS_ERR(p))
return PTR_ERR(p);
rcu_assign_pointer(ipe_active_policy, p);
}
return 0;
}
DEFINE_LSM(ipe) = {
.name = "ipe",
.init = ipe_init,
.blobs = &ipe_blobs,
};