1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * Copyright (C) 2009-2010 IBM Corporation
4 *
5 * Authors:
6 * Mimi Zohar <zohar@us.ibm.com>
7 */
8
9 #include <linux/types.h>
10 #include <linux/integrity.h>
11 #include <crypto/sha.h>
12 #include <linux/key.h>
13 #include <linux/audit.h>
14
15 /* iint action cache flags */
16 #define IMA_MEASURE 0x00000001
17 #define IMA_MEASURED 0x00000002
18 #define IMA_APPRAISE 0x00000004
19 #define IMA_APPRAISED 0x00000008
20 /*#define IMA_COLLECT 0x00000010 do not use this flag */
21 #define IMA_COLLECTED 0x00000020
22 #define IMA_AUDIT 0x00000040
23 #define IMA_AUDITED 0x00000080
24 #define IMA_HASH 0x00000100
25 #define IMA_HASHED 0x00000200
26
27 /* iint cache flags */
28 #define IMA_ACTION_FLAGS 0xff000000
29 #define IMA_DIGSIG_REQUIRED 0x01000000
30 #define IMA_PERMIT_DIRECTIO 0x02000000
31 #define IMA_NEW_FILE 0x04000000
32 #define EVM_IMMUTABLE_DIGSIG 0x08000000
33 #define IMA_FAIL_UNVERIFIABLE_SIGS 0x10000000
34 #define IMA_MODSIG_ALLOWED 0x20000000
35
36 #define IMA_DO_MASK (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \
37 IMA_HASH | IMA_APPRAISE_SUBMASK)
38 #define IMA_DONE_MASK (IMA_MEASURED | IMA_APPRAISED | IMA_AUDITED | \
39 IMA_HASHED | IMA_COLLECTED | \
40 IMA_APPRAISED_SUBMASK)
41
42 /* iint subaction appraise cache flags */
43 #define IMA_FILE_APPRAISE 0x00001000
44 #define IMA_FILE_APPRAISED 0x00002000
45 #define IMA_MMAP_APPRAISE 0x00004000
46 #define IMA_MMAP_APPRAISED 0x00008000
47 #define IMA_BPRM_APPRAISE 0x00010000
48 #define IMA_BPRM_APPRAISED 0x00020000
49 #define IMA_READ_APPRAISE 0x00040000
50 #define IMA_READ_APPRAISED 0x00080000
51 #define IMA_CREDS_APPRAISE 0x00100000
52 #define IMA_CREDS_APPRAISED 0x00200000
53 #define IMA_APPRAISE_SUBMASK (IMA_FILE_APPRAISE | IMA_MMAP_APPRAISE | \
54 IMA_BPRM_APPRAISE | IMA_READ_APPRAISE | \
55 IMA_CREDS_APPRAISE)
56 #define IMA_APPRAISED_SUBMASK (IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \
57 IMA_BPRM_APPRAISED | IMA_READ_APPRAISED | \
58 IMA_CREDS_APPRAISED)
59
60 /* iint cache atomic_flags */
61 #define IMA_CHANGE_XATTR 0
62 #define IMA_UPDATE_XATTR 1
63 #define IMA_CHANGE_ATTR 2
64 #define IMA_DIGSIG 3
65 #define IMA_MUST_MEASURE 4
66
67 enum evm_ima_xattr_type {
68 IMA_XATTR_DIGEST = 0x01,
69 EVM_XATTR_HMAC,
70 EVM_IMA_XATTR_DIGSIG,
71 IMA_XATTR_DIGEST_NG,
72 EVM_XATTR_PORTABLE_DIGSIG,
73 IMA_XATTR_LAST
74 };
75
76 struct evm_ima_xattr_data {
77 u8 type;
78 u8 data[];
79 } __packed;
80
81 /* Only used in the EVM HMAC code. */
82 struct evm_xattr {
83 struct evm_ima_xattr_data data;
84 u8 digest[SHA1_DIGEST_SIZE];
85 } __packed;
86
87 #define IMA_MAX_DIGEST_SIZE 64
88
89 struct ima_digest_data {
90 u8 algo;
91 u8 length;
92 union {
93 struct {
94 u8 unused;
95 u8 type;
96 } sha1;
97 struct {
98 u8 type;
99 u8 algo;
100 } ng;
101 u8 data[2];
102 } xattr;
103 u8 digest[0];
104 } __packed;
105
106 /*
107 * signature format v2 - for using with asymmetric keys
108 */
109 struct signature_v2_hdr {
110 uint8_t type; /* xattr type */
111 uint8_t version; /* signature format version */
112 uint8_t hash_algo; /* Digest algorithm [enum hash_algo] */
113 __be32 keyid; /* IMA key identifier - not X509/PGP specific */
114 __be16 sig_size; /* signature size */
115 uint8_t sig[0]; /* signature payload */
116 } __packed;
117
118 /* integrity data associated with an inode */
119 struct integrity_iint_cache {
120 struct rb_node rb_node; /* rooted in integrity_iint_tree */
121 struct mutex mutex; /* protects: version, flags, digest */
122 struct inode *inode; /* back pointer to inode in question */
123 u64 version; /* track inode changes */
124 unsigned long flags;
125 unsigned long measured_pcrs;
126 unsigned long atomic_flags;
127 enum integrity_status ima_file_status:4;
128 enum integrity_status ima_mmap_status:4;
129 enum integrity_status ima_bprm_status:4;
130 enum integrity_status ima_read_status:4;
131 enum integrity_status ima_creds_status:4;
132 enum integrity_status evm_status:4;
133 struct ima_digest_data *ima_hash;
134 };
135
136 /* rbtree tree calls to lookup, insert, delete
137 * integrity data associated with an inode.
138 */
139 struct integrity_iint_cache *integrity_iint_find(struct inode *inode);
140
141 int integrity_kernel_read(struct file *file, loff_t offset,
142 void *addr, unsigned long count);
143
144 #define INTEGRITY_KEYRING_EVM 0
145 #define INTEGRITY_KEYRING_IMA 1
146 #define INTEGRITY_KEYRING_PLATFORM 2
147 #define INTEGRITY_KEYRING_MAX 3
148
149 extern struct dentry *integrity_dir;
150
151 struct modsig;
152
153 #ifdef CONFIG_INTEGRITY_SIGNATURE
154
155 int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
156 const char *digest, int digestlen);
157 int integrity_modsig_verify(unsigned int id, const struct modsig *modsig);
158
159 int __init integrity_init_keyring(const unsigned int id);
160 int __init integrity_load_x509(const unsigned int id, const char *path);
161 int __init integrity_load_cert(const unsigned int id, const char *source,
162 const void *data, size_t len, key_perm_t perm);
163 #else
164
integrity_digsig_verify(const unsigned int id,const char * sig,int siglen,const char * digest,int digestlen)165 static inline int integrity_digsig_verify(const unsigned int id,
166 const char *sig, int siglen,
167 const char *digest, int digestlen)
168 {
169 return -EOPNOTSUPP;
170 }
171
integrity_modsig_verify(unsigned int id,const struct modsig * modsig)172 static inline int integrity_modsig_verify(unsigned int id,
173 const struct modsig *modsig)
174 {
175 return -EOPNOTSUPP;
176 }
177
integrity_init_keyring(const unsigned int id)178 static inline int integrity_init_keyring(const unsigned int id)
179 {
180 return 0;
181 }
182
integrity_load_cert(const unsigned int id,const char * source,const void * data,size_t len,key_perm_t perm)183 static inline int __init integrity_load_cert(const unsigned int id,
184 const char *source,
185 const void *data, size_t len,
186 key_perm_t perm)
187 {
188 return 0;
189 }
190 #endif /* CONFIG_INTEGRITY_SIGNATURE */
191
192 #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS
193 int asymmetric_verify(struct key *keyring, const char *sig,
194 int siglen, const char *data, int datalen);
195 #else
asymmetric_verify(struct key * keyring,const char * sig,int siglen,const char * data,int datalen)196 static inline int asymmetric_verify(struct key *keyring, const char *sig,
197 int siglen, const char *data, int datalen)
198 {
199 return -EOPNOTSUPP;
200 }
201 #endif
202
203 #ifdef CONFIG_IMA_APPRAISE_MODSIG
204 int ima_modsig_verify(struct key *keyring, const struct modsig *modsig);
205 #else
ima_modsig_verify(struct key * keyring,const struct modsig * modsig)206 static inline int ima_modsig_verify(struct key *keyring,
207 const struct modsig *modsig)
208 {
209 return -EOPNOTSUPP;
210 }
211 #endif
212
213 #ifdef CONFIG_IMA_LOAD_X509
214 void __init ima_load_x509(void);
215 #else
ima_load_x509(void)216 static inline void ima_load_x509(void)
217 {
218 }
219 #endif
220
221 #ifdef CONFIG_EVM_LOAD_X509
222 void __init evm_load_x509(void);
223 #else
evm_load_x509(void)224 static inline void evm_load_x509(void)
225 {
226 }
227 #endif
228
229 #ifdef CONFIG_INTEGRITY_AUDIT
230 /* declarations */
231 void integrity_audit_msg(int audit_msgno, struct inode *inode,
232 const unsigned char *fname, const char *op,
233 const char *cause, int result, int info);
234
235 static inline struct audit_buffer *
integrity_audit_log_start(struct audit_context * ctx,gfp_t gfp_mask,int type)236 integrity_audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, int type)
237 {
238 return audit_log_start(ctx, gfp_mask, type);
239 }
240
241 #else
integrity_audit_msg(int audit_msgno,struct inode * inode,const unsigned char * fname,const char * op,const char * cause,int result,int info)242 static inline void integrity_audit_msg(int audit_msgno, struct inode *inode,
243 const unsigned char *fname,
244 const char *op, const char *cause,
245 int result, int info)
246 {
247 }
248
249 static inline struct audit_buffer *
integrity_audit_log_start(struct audit_context * ctx,gfp_t gfp_mask,int type)250 integrity_audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, int type)
251 {
252 return NULL;
253 }
254
255 #endif
256
257 #ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING
258 void __init add_to_platform_keyring(const char *source, const void *data,
259 size_t len);
260 #else
add_to_platform_keyring(const char * source,const void * data,size_t len)261 static inline void __init add_to_platform_keyring(const char *source,
262 const void *data, size_t len)
263 {
264 }
265 #endif
266