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 #include <linux/audit.h>
19
20 /* iint action cache flags */
21 #define IMA_MEASURE 0x00000001
22 #define IMA_MEASURED 0x00000002
23 #define IMA_APPRAISE 0x00000004
24 #define IMA_APPRAISED 0x00000008
25 /*#define IMA_COLLECT 0x00000010 do not use this flag */
26 #define IMA_COLLECTED 0x00000020
27 #define IMA_AUDIT 0x00000040
28 #define IMA_AUDITED 0x00000080
29 #define IMA_HASH 0x00000100
30 #define IMA_HASHED 0x00000200
31
32 /* iint cache flags */
33 #define IMA_ACTION_FLAGS 0xff000000
34 #define IMA_DIGSIG_REQUIRED 0x01000000
35 #define IMA_PERMIT_DIRECTIO 0x02000000
36 #define IMA_NEW_FILE 0x04000000
37 #define EVM_IMMUTABLE_DIGSIG 0x08000000
38 #define IMA_FAIL_UNVERIFIABLE_SIGS 0x10000000
39
40 #define IMA_DO_MASK (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \
41 IMA_HASH | IMA_APPRAISE_SUBMASK)
42 #define IMA_DONE_MASK (IMA_MEASURED | IMA_APPRAISED | IMA_AUDITED | \
43 IMA_HASHED | IMA_COLLECTED | \
44 IMA_APPRAISED_SUBMASK)
45
46 /* iint subaction appraise cache flags */
47 #define IMA_FILE_APPRAISE 0x00001000
48 #define IMA_FILE_APPRAISED 0x00002000
49 #define IMA_MMAP_APPRAISE 0x00004000
50 #define IMA_MMAP_APPRAISED 0x00008000
51 #define IMA_BPRM_APPRAISE 0x00010000
52 #define IMA_BPRM_APPRAISED 0x00020000
53 #define IMA_READ_APPRAISE 0x00040000
54 #define IMA_READ_APPRAISED 0x00080000
55 #define IMA_CREDS_APPRAISE 0x00100000
56 #define IMA_CREDS_APPRAISED 0x00200000
57 #define IMA_APPRAISE_SUBMASK (IMA_FILE_APPRAISE | IMA_MMAP_APPRAISE | \
58 IMA_BPRM_APPRAISE | IMA_READ_APPRAISE | \
59 IMA_CREDS_APPRAISE)
60 #define IMA_APPRAISED_SUBMASK (IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \
61 IMA_BPRM_APPRAISED | IMA_READ_APPRAISED | \
62 IMA_CREDS_APPRAISED)
63
64 /* iint cache atomic_flags */
65 #define IMA_CHANGE_XATTR 0
66 #define IMA_UPDATE_XATTR 1
67 #define IMA_CHANGE_ATTR 2
68 #define IMA_DIGSIG 3
69 #define IMA_MUST_MEASURE 4
70
71 enum evm_ima_xattr_type {
72 IMA_XATTR_DIGEST = 0x01,
73 EVM_XATTR_HMAC,
74 EVM_IMA_XATTR_DIGSIG,
75 IMA_XATTR_DIGEST_NG,
76 EVM_XATTR_PORTABLE_DIGSIG,
77 IMA_XATTR_LAST
78 };
79
80 struct evm_ima_xattr_data {
81 u8 type;
82 u8 digest[SHA1_DIGEST_SIZE];
83 } __packed;
84
85 #define IMA_MAX_DIGEST_SIZE 64
86
87 struct ima_digest_data {
88 u8 algo;
89 u8 length;
90 union {
91 struct {
92 u8 unused;
93 u8 type;
94 } sha1;
95 struct {
96 u8 type;
97 u8 algo;
98 } ng;
99 u8 data[2];
100 } xattr;
101 u8 digest[0];
102 } __packed;
103
104 /*
105 * signature format v2 - for using with asymmetric keys
106 */
107 struct signature_v2_hdr {
108 uint8_t type; /* xattr type */
109 uint8_t version; /* signature format version */
110 uint8_t hash_algo; /* Digest algorithm [enum hash_algo] */
111 __be32 keyid; /* IMA key identifier - not X509/PGP specific */
112 __be16 sig_size; /* signature size */
113 uint8_t sig[0]; /* signature payload */
114 } __packed;
115
116 /* integrity data associated with an inode */
117 struct integrity_iint_cache {
118 struct rb_node rb_node; /* rooted in integrity_iint_tree */
119 struct mutex mutex; /* protects: version, flags, digest */
120 struct inode *inode; /* back pointer to inode in question */
121 u64 version; /* track inode changes */
122 unsigned long flags;
123 unsigned long measured_pcrs;
124 unsigned long atomic_flags;
125 enum integrity_status ima_file_status:4;
126 enum integrity_status ima_mmap_status:4;
127 enum integrity_status ima_bprm_status:4;
128 enum integrity_status ima_read_status:4;
129 enum integrity_status ima_creds_status:4;
130 enum integrity_status evm_status:4;
131 struct ima_digest_data *ima_hash;
132 };
133
134 /* rbtree tree calls to lookup, insert, delete
135 * integrity data associated with an inode.
136 */
137 struct integrity_iint_cache *integrity_iint_find(struct inode *inode);
138
139 int integrity_kernel_read(struct file *file, loff_t offset,
140 void *addr, unsigned long count);
141
142 #define INTEGRITY_KEYRING_EVM 0
143 #define INTEGRITY_KEYRING_IMA 1
144 #define INTEGRITY_KEYRING_MODULE 2
145 #define INTEGRITY_KEYRING_MAX 3
146
147 extern struct dentry *integrity_dir;
148
149 #ifdef CONFIG_INTEGRITY_SIGNATURE
150
151 int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
152 const char *digest, int digestlen);
153
154 int __init integrity_init_keyring(const unsigned int id);
155 int __init integrity_load_x509(const unsigned int id, const char *path);
156 #else
157
integrity_digsig_verify(const unsigned int id,const char * sig,int siglen,const char * digest,int digestlen)158 static inline int integrity_digsig_verify(const unsigned int id,
159 const char *sig, int siglen,
160 const char *digest, int digestlen)
161 {
162 return -EOPNOTSUPP;
163 }
164
integrity_init_keyring(const unsigned int id)165 static inline int integrity_init_keyring(const unsigned int id)
166 {
167 return 0;
168 }
169 #endif /* CONFIG_INTEGRITY_SIGNATURE */
170
171 #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS
172 int asymmetric_verify(struct key *keyring, const char *sig,
173 int siglen, const char *data, int datalen);
174 #else
asymmetric_verify(struct key * keyring,const char * sig,int siglen,const char * data,int datalen)175 static inline int asymmetric_verify(struct key *keyring, const char *sig,
176 int siglen, const char *data, int datalen)
177 {
178 return -EOPNOTSUPP;
179 }
180 #endif
181
182 #ifdef CONFIG_IMA_LOAD_X509
183 void __init ima_load_x509(void);
184 #else
ima_load_x509(void)185 static inline void ima_load_x509(void)
186 {
187 }
188 #endif
189
190 #ifdef CONFIG_EVM_LOAD_X509
191 void __init evm_load_x509(void);
192 #else
evm_load_x509(void)193 static inline void evm_load_x509(void)
194 {
195 }
196 #endif
197
198 #ifdef CONFIG_INTEGRITY_AUDIT
199 /* declarations */
200 void integrity_audit_msg(int audit_msgno, struct inode *inode,
201 const unsigned char *fname, const char *op,
202 const char *cause, int result, int info);
203
204 static inline struct audit_buffer *
integrity_audit_log_start(struct audit_context * ctx,gfp_t gfp_mask,int type)205 integrity_audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, int type)
206 {
207 return audit_log_start(ctx, gfp_mask, type);
208 }
209
210 #else
integrity_audit_msg(int audit_msgno,struct inode * inode,const unsigned char * fname,const char * op,const char * cause,int result,int info)211 static inline void integrity_audit_msg(int audit_msgno, struct inode *inode,
212 const unsigned char *fname,
213 const char *op, const char *cause,
214 int result, int info)
215 {
216 }
217
218 static inline struct audit_buffer *
integrity_audit_log_start(struct audit_context * ctx,gfp_t gfp_mask,int type)219 integrity_audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, int type)
220 {
221 return NULL;
222 }
223
224 #endif
225
