evm.h

 1/* SPDX-License-Identifier: GPL-2.0-only */
 2/*
 3 * Copyright (C) 2005-2010 IBM Corporation
 4 *
 5 * Authors:
 6 * Mimi Zohar <zohar@us.ibm.com>
 7 * Kylene Hall <kjhall@us.ibm.com>
 8 *
 9 * File: evm.h
10 */
11
12#ifndef __INTEGRITY_EVM_H
13#define __INTEGRITY_EVM_H
14
15#include <linux/xattr.h>
16#include <linux/security.h>
17
18#include "../integrity.h"
19
20#define EVM_INIT_HMAC	0x0001
21#define EVM_INIT_X509	0x0002
22#define EVM_ALLOW_METADATA_WRITES	0x0004
23#define EVM_SETUP_COMPLETE 0x80000000 /* userland has signaled key load */
24
25#define EVM_KEY_MASK (EVM_INIT_HMAC | EVM_INIT_X509)
26#define EVM_INIT_MASK (EVM_INIT_HMAC | EVM_INIT_X509 | EVM_SETUP_COMPLETE | \
27		       EVM_ALLOW_METADATA_WRITES)
28
29struct xattr_list {
30	struct list_head list;
31	char *name;
32	bool enabled;
33};
34
35#define EVM_NEW_FILE			0x00000001
36#define EVM_IMMUTABLE_DIGSIG		0x00000002
37
38/* EVM integrity metadata associated with an inode */
39struct evm_iint_cache {
40	unsigned long flags;
41	enum integrity_status evm_status:4;
42	struct integrity_inode_attributes metadata_inode;
43};
44
45extern struct lsm_blob_sizes evm_blob_sizes;
46
47static inline struct evm_iint_cache *evm_iint_inode(const struct inode *inode)
48{
49	if (unlikely(!inode->i_security))
50		return NULL;
51
52	return inode->i_security + evm_blob_sizes.lbs_inode;
53}
54
55extern int evm_initialized;
56
57#define EVM_ATTR_FSUUID		0x0001
58
59extern int evm_hmac_attrs;
60
61/* List of EVM protected security xattrs */
62extern struct list_head evm_config_xattrnames;
63
64struct evm_digest {
65	struct ima_digest_data_hdr hdr;
66	char digest[IMA_MAX_DIGEST_SIZE];
67} __packed;
68
69int evm_protected_xattr(const char *req_xattr_name);
70
71int evm_init_key(void);
72int evm_update_evmxattr(struct dentry *dentry,
73			const char *req_xattr_name,
74			const char *req_xattr_value,
75			size_t req_xattr_value_len);
76int evm_calc_hmac(struct dentry *dentry, const char *req_xattr_name,
77		  const char *req_xattr_value,
78		  size_t req_xattr_value_len, struct evm_digest *data,
79		  struct evm_iint_cache *iint);
80int evm_calc_hash(struct dentry *dentry, const char *req_xattr_name,
81		  const char *req_xattr_value,
82		  size_t req_xattr_value_len, char type,
83		  struct evm_digest *data, struct evm_iint_cache *iint);
84int evm_init_hmac(struct inode *inode, const struct xattr *xattrs,
85		  char *hmac_val);
86int evm_init_secfs(void);
87
88#endif