xref: /linux/security/integrity/integrity.h (revision 93d90ad708b8da6efc0e487b66111aa9db7f70c7)
1 /*
2  * Copyright (C) 2009-2010 IBM Corporation
3  *
4  * Authors:
5  * Mimi Zohar <zohar@us.ibm.com>
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License as
9  * published by the Free Software Foundation, version 2 of the
10  * License.
11  *
12  */
13 
14 #include <linux/types.h>
15 #include <linux/integrity.h>
16 #include <crypto/sha.h>
17 #include <linux/key.h>
18 
19 /* iint action cache flags */
20 #define IMA_MEASURE		0x00000001
21 #define IMA_MEASURED		0x00000002
22 #define IMA_APPRAISE		0x00000004
23 #define IMA_APPRAISED		0x00000008
24 /*#define IMA_COLLECT		0x00000010  do not use this flag */
25 #define IMA_COLLECTED		0x00000020
26 #define IMA_AUDIT		0x00000040
27 #define IMA_AUDITED		0x00000080
28 
29 /* iint cache flags */
30 #define IMA_ACTION_FLAGS	0xff000000
31 #define IMA_DIGSIG		0x01000000
32 #define IMA_DIGSIG_REQUIRED	0x02000000
33 #define IMA_PERMIT_DIRECTIO	0x04000000
34 #define IMA_NEW_FILE		0x08000000
35 
36 #define IMA_DO_MASK		(IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \
37 				 IMA_APPRAISE_SUBMASK)
38 #define IMA_DONE_MASK		(IMA_MEASURED | IMA_APPRAISED | IMA_AUDITED | \
39 				 IMA_COLLECTED | IMA_APPRAISED_SUBMASK)
40 
41 /* iint subaction appraise cache flags */
42 #define IMA_FILE_APPRAISE	0x00000100
43 #define IMA_FILE_APPRAISED	0x00000200
44 #define IMA_MMAP_APPRAISE	0x00000400
45 #define IMA_MMAP_APPRAISED	0x00000800
46 #define IMA_BPRM_APPRAISE	0x00001000
47 #define IMA_BPRM_APPRAISED	0x00002000
48 #define IMA_MODULE_APPRAISE	0x00004000
49 #define IMA_MODULE_APPRAISED	0x00008000
50 #define IMA_FIRMWARE_APPRAISE	0x00010000
51 #define IMA_FIRMWARE_APPRAISED	0x00020000
52 #define IMA_APPRAISE_SUBMASK	(IMA_FILE_APPRAISE | IMA_MMAP_APPRAISE | \
53 				 IMA_BPRM_APPRAISE | IMA_MODULE_APPRAISE | \
54 				 IMA_FIRMWARE_APPRAISE)
55 #define IMA_APPRAISED_SUBMASK	(IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \
56 				 IMA_BPRM_APPRAISED | IMA_MODULE_APPRAISED | \
57 				 IMA_FIRMWARE_APPRAISED)
58 
59 enum evm_ima_xattr_type {
60 	IMA_XATTR_DIGEST = 0x01,
61 	EVM_XATTR_HMAC,
62 	EVM_IMA_XATTR_DIGSIG,
63 	IMA_XATTR_DIGEST_NG,
64 	IMA_XATTR_LAST
65 };
66 
67 struct evm_ima_xattr_data {
68 	u8 type;
69 	u8 digest[SHA1_DIGEST_SIZE];
70 } __packed;
71 
72 #define IMA_MAX_DIGEST_SIZE	64
73 
74 struct ima_digest_data {
75 	u8 algo;
76 	u8 length;
77 	union {
78 		struct {
79 			u8 unused;
80 			u8 type;
81 		} sha1;
82 		struct {
83 			u8 type;
84 			u8 algo;
85 		} ng;
86 		u8 data[2];
87 	} xattr;
88 	u8 digest[0];
89 } __packed;
90 
91 /*
92  * signature format v2 - for using with asymmetric keys
93  */
94 struct signature_v2_hdr {
95 	uint8_t type;		/* xattr type */
96 	uint8_t version;	/* signature format version */
97 	uint8_t	hash_algo;	/* Digest algorithm [enum pkey_hash_algo] */
98 	uint32_t keyid;		/* IMA key identifier - not X509/PGP specific */
99 	uint16_t sig_size;	/* signature size */
100 	uint8_t sig[0];		/* signature payload */
101 } __packed;
102 
103 /* integrity data associated with an inode */
104 struct integrity_iint_cache {
105 	struct rb_node rb_node;	/* rooted in integrity_iint_tree */
106 	struct inode *inode;	/* back pointer to inode in question */
107 	u64 version;		/* track inode changes */
108 	unsigned long flags;
109 	enum integrity_status ima_file_status:4;
110 	enum integrity_status ima_mmap_status:4;
111 	enum integrity_status ima_bprm_status:4;
112 	enum integrity_status ima_module_status:4;
113 	enum integrity_status ima_firmware_status:4;
114 	enum integrity_status evm_status:4;
115 	struct ima_digest_data *ima_hash;
116 };
117 
118 /* rbtree tree calls to lookup, insert, delete
119  * integrity data associated with an inode.
120  */
121 struct integrity_iint_cache *integrity_iint_find(struct inode *inode);
122 
123 int integrity_kernel_read(struct file *file, loff_t offset,
124 			  char *addr, unsigned long count);
125 int __init integrity_read_file(const char *path, char **data);
126 
127 #define INTEGRITY_KEYRING_EVM		0
128 #define INTEGRITY_KEYRING_MODULE	1
129 #define INTEGRITY_KEYRING_IMA		2
130 #define INTEGRITY_KEYRING_MAX		3
131 
132 #ifdef CONFIG_INTEGRITY_SIGNATURE
133 
134 int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
135 			    const char *digest, int digestlen);
136 
137 int __init integrity_init_keyring(const unsigned int id);
138 int __init integrity_load_x509(const unsigned int id, char *path);
139 #else
140 
141 static inline int integrity_digsig_verify(const unsigned int id,
142 					  const char *sig, int siglen,
143 					  const char *digest, int digestlen)
144 {
145 	return -EOPNOTSUPP;
146 }
147 
148 static inline int integrity_init_keyring(const unsigned int id)
149 {
150 	return 0;
151 }
152 
153 #endif /* CONFIG_INTEGRITY_SIGNATURE */
154 
155 #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS
156 int asymmetric_verify(struct key *keyring, const char *sig,
157 		      int siglen, const char *data, int datalen);
158 #else
159 static inline int asymmetric_verify(struct key *keyring, const char *sig,
160 				    int siglen, const char *data, int datalen)
161 {
162 	return -EOPNOTSUPP;
163 }
164 #endif
165 
166 #ifdef CONFIG_IMA_LOAD_X509
167 void __init ima_load_x509(void);
168 #else
169 static inline void ima_load_x509(void)
170 {
171 }
172 #endif
173 
174 #ifdef CONFIG_INTEGRITY_AUDIT
175 /* declarations */
176 void integrity_audit_msg(int audit_msgno, struct inode *inode,
177 			 const unsigned char *fname, const char *op,
178 			 const char *cause, int result, int info);
179 #else
180 static inline void integrity_audit_msg(int audit_msgno, struct inode *inode,
181 				       const unsigned char *fname,
182 				       const char *op, const char *cause,
183 				       int result, int info)
184 {
185 }
186 #endif
187