xref: /linux/security/integrity/evm/evm.h (revision e6a901a00822659181c93c86d8bbc2a17779fddc)
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 
29 struct 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 */
39 struct evm_iint_cache {
40 	unsigned long flags;
41 	enum integrity_status evm_status:4;
42 };
43 
44 extern struct lsm_blob_sizes evm_blob_sizes;
45 
46 static inline struct evm_iint_cache *evm_iint_inode(const struct inode *inode)
47 {
48 	if (unlikely(!inode->i_security))
49 		return NULL;
50 
51 	return inode->i_security + evm_blob_sizes.lbs_inode;
52 }
53 
54 extern int evm_initialized;
55 
56 #define EVM_ATTR_FSUUID		0x0001
57 
58 extern int evm_hmac_attrs;
59 
60 /* List of EVM protected security xattrs */
61 extern struct list_head evm_config_xattrnames;
62 
63 struct evm_digest {
64 	struct ima_digest_data hdr;
65 	char digest[IMA_MAX_DIGEST_SIZE];
66 } __packed;
67 
68 int evm_protected_xattr(const char *req_xattr_name);
69 
70 int evm_init_key(void);
71 int evm_update_evmxattr(struct dentry *dentry,
72 			const char *req_xattr_name,
73 			const char *req_xattr_value,
74 			size_t req_xattr_value_len);
75 int evm_calc_hmac(struct dentry *dentry, const char *req_xattr_name,
76 		  const char *req_xattr_value,
77 		  size_t req_xattr_value_len, struct evm_digest *data);
78 int evm_calc_hash(struct dentry *dentry, const char *req_xattr_name,
79 		  const char *req_xattr_value,
80 		  size_t req_xattr_value_len, char type,
81 		  struct evm_digest *data);
82 int evm_init_hmac(struct inode *inode, const struct xattr *xattrs,
83 		  char *hmac_val);
84 int evm_init_secfs(void);
85 
86 #endif
87