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_ACTION_RULE_FLAGS 0x06000000
32 #define IMA_DIGSIG_REQUIRED 0x01000000
33 #define IMA_PERMIT_DIRECTIO 0x02000000
34 #define IMA_NEW_FILE 0x04000000
35 #define EVM_IMMUTABLE_DIGSIG 0x08000000
36
37 #define IMA_DO_MASK (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \
38 IMA_APPRAISE_SUBMASK)
39 #define IMA_DONE_MASK (IMA_MEASURED | IMA_APPRAISED | IMA_AUDITED | \
40 IMA_COLLECTED | IMA_APPRAISED_SUBMASK)
41
42 /* iint subaction appraise cache flags */
43 #define IMA_FILE_APPRAISE 0x00000100
44 #define IMA_FILE_APPRAISED 0x00000200
45 #define IMA_MMAP_APPRAISE 0x00000400
46 #define IMA_MMAP_APPRAISED 0x00000800
47 #define IMA_BPRM_APPRAISE 0x00001000
48 #define IMA_BPRM_APPRAISED 0x00002000
49 #define IMA_READ_APPRAISE 0x00004000
50 #define IMA_READ_APPRAISED 0x00008000
51 #define IMA_APPRAISE_SUBMASK (IMA_FILE_APPRAISE | IMA_MMAP_APPRAISE | \
52 IMA_BPRM_APPRAISE | IMA_READ_APPRAISE)
53 #define IMA_APPRAISED_SUBMASK (IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \
54 IMA_BPRM_APPRAISED | IMA_READ_APPRAISED)
55
56 /* iint cache atomic_flags */
57 #define IMA_CHANGE_XATTR 0
58 #define IMA_UPDATE_XATTR 1
59 #define IMA_CHANGE_ATTR 2
60 #define IMA_DIGSIG 3
61 #define IMA_MUST_MEASURE 4
62
63 enum evm_ima_xattr_type {
64 IMA_XATTR_DIGEST = 0x01,
65 EVM_XATTR_HMAC,
66 EVM_IMA_XATTR_DIGSIG,
67 IMA_XATTR_DIGEST_NG,
68 EVM_XATTR_PORTABLE_DIGSIG,
69 IMA_XATTR_LAST
70 };
71
72 struct evm_ima_xattr_data {
73 u8 type;
74 u8 digest[SHA1_DIGEST_SIZE];
75 } __packed;
76
77 #define IMA_MAX_DIGEST_SIZE 64
78
79 struct ima_digest_data {
80 u8 algo;
81 u8 length;
82 union {
83 struct {
84 u8 unused;
85 u8 type;
86 } sha1;
87 struct {
88 u8 type;
89 u8 algo;
90 } ng;
91 u8 data[2];
92 } xattr;
93 u8 digest[0];
94 } __packed;
95
96 /*
97 * signature format v2 - for using with asymmetric keys
98 */
99 struct signature_v2_hdr {
100 uint8_t type; /* xattr type */
101 uint8_t version; /* signature format version */
102 uint8_t hash_algo; /* Digest algorithm [enum hash_algo] */
103 __be32 keyid; /* IMA key identifier - not X509/PGP specific */
104 __be16 sig_size; /* signature size */
105 uint8_t sig[0]; /* signature payload */
106 } __packed;
107
108 /* integrity data associated with an inode */
109 struct integrity_iint_cache {
110 struct rb_node rb_node; /* rooted in integrity_iint_tree */
111 struct mutex mutex; /* protects: version, flags, digest */
112 struct inode *inode; /* back pointer to inode in question */
113 u64 version; /* track inode changes */
114 unsigned long flags;
115 unsigned long measured_pcrs;
116 unsigned long atomic_flags;
117 enum integrity_status ima_file_status:4;
118 enum integrity_status ima_mmap_status:4;
119 enum integrity_status ima_bprm_status:4;
120 enum integrity_status ima_read_status:4;
121 enum integrity_status evm_status:4;
122 struct ima_digest_data *ima_hash;
123 };
124
125 /* rbtree tree calls to lookup, insert, delete
126 * integrity data associated with an inode.
127 */
128 struct integrity_iint_cache *integrity_iint_find(struct inode *inode);
129
130 int integrity_kernel_read(struct file *file, loff_t offset,
131 void *addr, unsigned long count);
132
133 int __init integrity_read_file(const char *path, char **data);
134
135 #define INTEGRITY_KEYRING_EVM 0
136 #define INTEGRITY_KEYRING_IMA 1
137 #define INTEGRITY_KEYRING_MODULE 2
138 #define INTEGRITY_KEYRING_MAX 3
139
140 #ifdef CONFIG_INTEGRITY_SIGNATURE
141
142 int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
143 const char *digest, int digestlen);
144
145 int __init integrity_init_keyring(const unsigned int id);
146 int __init integrity_load_x509(const unsigned int id, const char *path);
147 #else
148
integrity_digsig_verify(const unsigned int id,const char * sig,int siglen,const char * digest,int digestlen)149 static inline int integrity_digsig_verify(const unsigned int id,
150 const char *sig, int siglen,
151 const char *digest, int digestlen)
152 {
153 return -EOPNOTSUPP;
154 }
155
integrity_init_keyring(const unsigned int id)156 static inline int integrity_init_keyring(const unsigned int id)
157 {
158 return 0;
159 }
160 #endif /* CONFIG_INTEGRITY_SIGNATURE */
161
162 #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS
163 int asymmetric_verify(struct key *keyring, const char *sig,
164 int siglen, const char *data, int datalen);
165 #else
asymmetric_verify(struct key * keyring,const char * sig,int siglen,const char * data,int datalen)166 static inline int asymmetric_verify(struct key *keyring, const char *sig,
167 int siglen, const char *data, int datalen)
168 {
169 return -EOPNOTSUPP;
170 }
171 #endif
172
173 #ifdef CONFIG_IMA_LOAD_X509
174 void __init ima_load_x509(void);
175 #else
ima_load_x509(void)176 static inline void ima_load_x509(void)
177 {
178 }
179 #endif
180
181 #ifdef CONFIG_EVM_LOAD_X509
182 void __init evm_load_x509(void);
183 #else
evm_load_x509(void)184 static inline void evm_load_x509(void)
185 {
186 }
187 #endif
188
189 #ifdef CONFIG_INTEGRITY_AUDIT
190 /* declarations */
191 void integrity_audit_msg(int audit_msgno, struct inode *inode,
192 const unsigned char *fname, const char *op,
193 const char *cause, int result, int info);
194 #else
integrity_audit_msg(int audit_msgno,struct inode * inode,const unsigned char * fname,const char * op,const char * cause,int result,int info)195 static inline void integrity_audit_msg(int audit_msgno, struct inode *inode,
196 const unsigned char *fname,
197 const char *op, const char *cause,
198 int result, int info)
199 {
200 }
201 #endif
202