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 
34 #define IMA_DO_MASK		(IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \
35 				 IMA_APPRAISE_SUBMASK)
36 #define IMA_DONE_MASK		(IMA_MEASURED | IMA_APPRAISED | IMA_AUDITED | \
37 				 IMA_COLLECTED | IMA_APPRAISED_SUBMASK)
38 
39 /* iint subaction appraise cache flags */
40 #define IMA_FILE_APPRAISE	0x00000100
41 #define IMA_FILE_APPRAISED	0x00000200
42 #define IMA_MMAP_APPRAISE	0x00000400
43 #define IMA_MMAP_APPRAISED	0x00000800
44 #define IMA_BPRM_APPRAISE	0x00001000
45 #define IMA_BPRM_APPRAISED	0x00002000
46 #define IMA_MODULE_APPRAISE	0x00004000
47 #define IMA_MODULE_APPRAISED	0x00008000
48 #define IMA_APPRAISE_SUBMASK	(IMA_FILE_APPRAISE | IMA_MMAP_APPRAISE | \
49 				 IMA_BPRM_APPRAISE | IMA_MODULE_APPRAISE)
50 #define IMA_APPRAISED_SUBMASK	(IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \
51 				 IMA_BPRM_APPRAISED | IMA_MODULE_APPRAISED)
52 
53 enum evm_ima_xattr_type {
54 	IMA_XATTR_DIGEST = 0x01,
55 	EVM_XATTR_HMAC,
56 	EVM_IMA_XATTR_DIGSIG,
57 };
58 
59 struct evm_ima_xattr_data {
60 	u8 type;
61 	u8 digest[SHA1_DIGEST_SIZE];
62 }  __attribute__((packed));
63 
64 /* integrity data associated with an inode */
65 struct integrity_iint_cache {
66 	struct rb_node rb_node; /* rooted in integrity_iint_tree */
67 	struct inode *inode;	/* back pointer to inode in question */
68 	u64 version;		/* track inode changes */
69 	unsigned long flags;
70 	struct evm_ima_xattr_data ima_xattr;
71 	enum integrity_status ima_file_status:4;
72 	enum integrity_status ima_mmap_status:4;
73 	enum integrity_status ima_bprm_status:4;
74 	enum integrity_status ima_module_status:4;
75 	enum integrity_status evm_status:4;
76 };
77 
78 /* rbtree tree calls to lookup, insert, delete
79  * integrity data associated with an inode.
80  */
81 struct integrity_iint_cache *integrity_iint_insert(struct inode *inode);
82 struct integrity_iint_cache *integrity_iint_find(struct inode *inode);
83 
84 #define INTEGRITY_KEYRING_EVM		0
85 #define INTEGRITY_KEYRING_MODULE	1
86 #define INTEGRITY_KEYRING_IMA		2
87 #define INTEGRITY_KEYRING_MAX		3
88 
89 #ifdef CONFIG_INTEGRITY_SIGNATURE
90 
91 int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
92 					const char *digest, int digestlen);
93 
94 #else
95 
96 static inline int integrity_digsig_verify(const unsigned int id,
97 					  const char *sig, int siglen,
98 					  const char *digest, int digestlen)
99 {
100 	return -EOPNOTSUPP;
101 }
102 
103 #endif /* CONFIG_INTEGRITY_SIGNATURE */
104 
105 #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS
106 int asymmetric_verify(struct key *keyring, const char *sig,
107 		      int siglen, const char *data, int datalen);
108 #else
109 static inline int asymmetric_verify(struct key *keyring, const char *sig,
110 				    int siglen, const char *data, int datalen)
111 {
112 	return -EOPNOTSUPP;
113 }
114 #endif
115 
116 #ifdef CONFIG_INTEGRITY_AUDIT
117 /* declarations */
118 void integrity_audit_msg(int audit_msgno, struct inode *inode,
119 			 const unsigned char *fname, const char *op,
120 			 const char *cause, int result, int info);
121 #else
122 static inline void integrity_audit_msg(int audit_msgno, struct inode *inode,
123 				       const unsigned char *fname,
124 				       const char *op, const char *cause,
125 				       int result, int info)
126 {
127 }
128 #endif
129 
130 /* set during initialization */
131 extern int iint_initialized;
132