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 #ifdef pr_fmt
10 #undef pr_fmt
11 #endif
12
13 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14
15 #include <linux/types.h>
16 #include <linux/integrity.h>
17 #include <crypto/sha1.h>
18 #include <linux/key.h>
19 #include <linux/audit.h>
20
21 /* iint action cache flags */
22 #define IMA_MEASURE 0x00000001
23 #define IMA_MEASURED 0x00000002
24 #define IMA_APPRAISE 0x00000004
25 #define IMA_APPRAISED 0x00000008
26 /*#define IMA_COLLECT 0x00000010 do not use this flag */
27 #define IMA_COLLECTED 0x00000020
28 #define IMA_AUDIT 0x00000040
29 #define IMA_AUDITED 0x00000080
30 #define IMA_HASH 0x00000100
31 #define IMA_HASHED 0x00000200
32
33 /* iint cache flags */
34 #define IMA_ACTION_FLAGS 0xff000000
35 #define IMA_DIGSIG_REQUIRED 0x01000000
36 #define IMA_PERMIT_DIRECTIO 0x02000000
37 #define IMA_NEW_FILE 0x04000000
38 #define EVM_IMMUTABLE_DIGSIG 0x08000000
39 #define IMA_FAIL_UNVERIFIABLE_SIGS 0x10000000
40 #define IMA_MODSIG_ALLOWED 0x20000000
41 #define IMA_CHECK_BLACKLIST 0x40000000
42
43 #define IMA_DO_MASK (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \
44 IMA_HASH | IMA_APPRAISE_SUBMASK)
45 #define IMA_DONE_MASK (IMA_MEASURED | IMA_APPRAISED | IMA_AUDITED | \
46 IMA_HASHED | IMA_COLLECTED | \
47 IMA_APPRAISED_SUBMASK)
48
49 /* iint subaction appraise cache flags */
50 #define IMA_FILE_APPRAISE 0x00001000
51 #define IMA_FILE_APPRAISED 0x00002000
52 #define IMA_MMAP_APPRAISE 0x00004000
53 #define IMA_MMAP_APPRAISED 0x00008000
54 #define IMA_BPRM_APPRAISE 0x00010000
55 #define IMA_BPRM_APPRAISED 0x00020000
56 #define IMA_READ_APPRAISE 0x00040000
57 #define IMA_READ_APPRAISED 0x00080000
58 #define IMA_CREDS_APPRAISE 0x00100000
59 #define IMA_CREDS_APPRAISED 0x00200000
60 #define IMA_APPRAISE_SUBMASK (IMA_FILE_APPRAISE | IMA_MMAP_APPRAISE | \
61 IMA_BPRM_APPRAISE | IMA_READ_APPRAISE | \
62 IMA_CREDS_APPRAISE)
63 #define IMA_APPRAISED_SUBMASK (IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \
64 IMA_BPRM_APPRAISED | IMA_READ_APPRAISED | \
65 IMA_CREDS_APPRAISED)
66
67 /* iint cache atomic_flags */
68 #define IMA_CHANGE_XATTR 0
69 #define IMA_UPDATE_XATTR 1
70 #define IMA_CHANGE_ATTR 2
71 #define IMA_DIGSIG 3
72 #define IMA_MUST_MEASURE 4
73
74 enum evm_ima_xattr_type {
75 IMA_XATTR_DIGEST = 0x01,
76 EVM_XATTR_HMAC,
77 EVM_IMA_XATTR_DIGSIG,
78 IMA_XATTR_DIGEST_NG,
79 EVM_XATTR_PORTABLE_DIGSIG,
80 IMA_XATTR_LAST
81 };
82
83 struct evm_ima_xattr_data {
84 u8 type;
85 u8 data[];
86 } __packed;
87
88 /* Only used in the EVM HMAC code. */
89 struct evm_xattr {
90 struct evm_ima_xattr_data data;
91 u8 digest[SHA1_DIGEST_SIZE];
92 } __packed;
93
94 #define IMA_MAX_DIGEST_SIZE 64
95
96 struct ima_digest_data {
97 u8 algo;
98 u8 length;
99 union {
100 struct {
101 u8 unused;
102 u8 type;
103 } sha1;
104 struct {
105 u8 type;
106 u8 algo;
107 } ng;
108 u8 data[2];
109 } xattr;
110 u8 digest[];
111 } __packed;
112
113 /*
114 * signature format v2 - for using with asymmetric keys
115 */
116 struct signature_v2_hdr {
117 uint8_t type; /* xattr type */
118 uint8_t version; /* signature format version */
119 uint8_t hash_algo; /* Digest algorithm [enum hash_algo] */
120 __be32 keyid; /* IMA key identifier - not X509/PGP specific */
121 __be16 sig_size; /* signature size */
122 uint8_t sig[]; /* signature payload */
123 } __packed;
124
125 /* integrity data associated with an inode */
126 struct integrity_iint_cache {
127 struct rb_node rb_node; /* rooted in integrity_iint_tree */
128 struct mutex mutex; /* protects: version, flags, digest */
129 struct inode *inode; /* back pointer to inode in question */
130 u64 version; /* track inode changes */
131 unsigned long flags;
132 unsigned long measured_pcrs;
133 unsigned long atomic_flags;
134 unsigned long real_ino;
135 dev_t real_dev;
136 enum integrity_status ima_file_status:4;
137 enum integrity_status ima_mmap_status:4;
138 enum integrity_status ima_bprm_status:4;
139 enum integrity_status ima_read_status:4;
140 enum integrity_status ima_creds_status:4;
141 enum integrity_status evm_status:4;
142 struct ima_digest_data *ima_hash;
143 };
144
145 /* rbtree tree calls to lookup, insert, delete
146 * integrity data associated with an inode.
147 */
148 struct integrity_iint_cache *integrity_iint_find(struct inode *inode);
149
150 int integrity_kernel_read(struct file *file, loff_t offset,
151 void *addr, unsigned long count);
152
153 #define INTEGRITY_KEYRING_EVM 0
154 #define INTEGRITY_KEYRING_IMA 1
155 #define INTEGRITY_KEYRING_PLATFORM 2
156 #define INTEGRITY_KEYRING_MAX 3
157
158 extern struct dentry *integrity_dir;
159
160 struct modsig;
161
162 #ifdef CONFIG_INTEGRITY_SIGNATURE
163
164 int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
165 const char *digest, int digestlen);
166 int integrity_modsig_verify(unsigned int id, const struct modsig *modsig);
167
168 int __init integrity_init_keyring(const unsigned int id);
169 int __init integrity_load_x509(const unsigned int id, const char *path);
170 int __init integrity_load_cert(const unsigned int id, const char *source,
171 const void *data, size_t len, key_perm_t perm);
172 #else
173
integrity_digsig_verify(const unsigned int id,const char * sig,int siglen,const char * digest,int digestlen)174 static inline int integrity_digsig_verify(const unsigned int id,
175 const char *sig, int siglen,
176 const char *digest, int digestlen)
177 {
178 return -EOPNOTSUPP;
179 }
180
integrity_modsig_verify(unsigned int id,const struct modsig * modsig)181 static inline int integrity_modsig_verify(unsigned int id,
182 const struct modsig *modsig)
183 {
184 return -EOPNOTSUPP;
185 }
186
integrity_init_keyring(const unsigned int id)187 static inline int integrity_init_keyring(const unsigned int id)
188 {
189 return 0;
190 }
191
integrity_load_cert(const unsigned int id,const char * source,const void * data,size_t len,key_perm_t perm)192 static inline int __init integrity_load_cert(const unsigned int id,
193 const char *source,
194 const void *data, size_t len,
195 key_perm_t perm)
196 {
197 return 0;
198 }
199 #endif /* CONFIG_INTEGRITY_SIGNATURE */
200
201 #ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS
202 int asymmetric_verify(struct key *keyring, const char *sig,
203 int siglen, const char *data, int datalen);
204 #else
asymmetric_verify(struct key * keyring,const char * sig,int siglen,const char * data,int datalen)205 static inline int asymmetric_verify(struct key *keyring, const char *sig,
206 int siglen, const char *data, int datalen)
207 {
208 return -EOPNOTSUPP;
209 }
210 #endif
211
212 #ifdef CONFIG_IMA_APPRAISE_MODSIG
213 int ima_modsig_verify(struct key *keyring, const struct modsig *modsig);
214 #else
ima_modsig_verify(struct key * keyring,const struct modsig * modsig)215 static inline int ima_modsig_verify(struct key *keyring,
216 const struct modsig *modsig)
217 {
218 return -EOPNOTSUPP;
219 }
220 #endif
221
222 #ifdef CONFIG_IMA_LOAD_X509
223 void __init ima_load_x509(void);
224 #else
ima_load_x509(void)225 static inline void ima_load_x509(void)
226 {
227 }
228 #endif
229
230 #ifdef CONFIG_EVM_LOAD_X509
231 void __init evm_load_x509(void);
232 #else
evm_load_x509(void)233 static inline void evm_load_x509(void)
234 {
235 }
236 #endif
237
238 #ifdef CONFIG_INTEGRITY_AUDIT
239 /* declarations */
240 void integrity_audit_msg(int audit_msgno, struct inode *inode,
241 const unsigned char *fname, const char *op,
242 const char *cause, int result, int info);
243
244 void integrity_audit_message(int audit_msgno, struct inode *inode,
245 const unsigned char *fname, const char *op,
246 const char *cause, int result, int info,
247 int errno);
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 audit_log_start(ctx, gfp_mask, type);
253 }
254
255 #else
integrity_audit_msg(int audit_msgno,struct inode * inode,const unsigned char * fname,const char * op,const char * cause,int result,int info)256 static inline void integrity_audit_msg(int audit_msgno, struct inode *inode,
257 const unsigned char *fname,
258 const char *op, const char *cause,
259 int result, int info)
260 {
261 }
262
integrity_audit_message(int audit_msgno,struct inode * inode,const unsigned char * fname,const char * op,const char * cause,int result,int info,int errno)263 static inline void integrity_audit_message(int audit_msgno,
264 struct inode *inode,
265 const unsigned char *fname,
266 const char *op, const char *cause,
267 int result, int info, int errno)
268 {
269 }
270
271 static inline struct audit_buffer *
integrity_audit_log_start(struct audit_context * ctx,gfp_t gfp_mask,int type)272 integrity_audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, int type)
273 {
274 return NULL;
275 }
276
277 #endif
278
279 #ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING
280 void __init add_to_platform_keyring(const char *source, const void *data,
281 size_t len);
282 #else
add_to_platform_keyring(const char * source,const void * data,size_t len)283 static inline void __init add_to_platform_keyring(const char *source,
284 const void *data, size_t len)
285 {
286 }
287 #endif
288