1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Copyright (C) 2005,2006,2007,2008 IBM Corporation 4 * 5 * Authors: 6 * Reiner Sailer <sailer@watson.ibm.com> 7 * Mimi Zohar <zohar@us.ibm.com> 8 * 9 * File: ima.h 10 * internal Integrity Measurement Architecture (IMA) definitions 11 */ 12 13 #ifndef __LINUX_IMA_H 14 #define __LINUX_IMA_H 15 16 #include <linux/types.h> 17 #include <linux/crypto.h> 18 #include <linux/fs.h> 19 #include <linux/security.h> 20 #include <linux/hash.h> 21 #include <linux/tpm.h> 22 #include <linux/audit.h> 23 #include <crypto/hash_info.h> 24 25 #include "../integrity.h" 26 27 #ifdef CONFIG_HAVE_IMA_KEXEC 28 #include <asm/ima.h> 29 #endif 30 31 enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_BINARY_NO_FIELD_LEN, 32 IMA_SHOW_BINARY_OLD_STRING_FMT, IMA_SHOW_ASCII }; 33 enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8 }; 34 35 /* digest size for IMA, fits SHA1 or MD5 */ 36 #define IMA_DIGEST_SIZE SHA1_DIGEST_SIZE 37 #define IMA_EVENT_NAME_LEN_MAX 255 38 39 #define IMA_HASH_BITS 9 40 #define IMA_MEASURE_HTABLE_SIZE (1 << IMA_HASH_BITS) 41 42 #define IMA_TEMPLATE_FIELD_ID_MAX_LEN 16 43 #define IMA_TEMPLATE_NUM_FIELDS_MAX 15 44 45 #define IMA_TEMPLATE_IMA_NAME "ima" 46 #define IMA_TEMPLATE_IMA_FMT "d|n" 47 48 /* current content of the policy */ 49 extern int ima_policy_flag; 50 51 /* set during initialization */ 52 extern int ima_hash_algo; 53 extern int ima_appraise; 54 extern struct tpm_chip *ima_tpm_chip; 55 56 /* IMA event related data */ 57 struct ima_event_data { 58 struct integrity_iint_cache *iint; 59 struct file *file; 60 const unsigned char *filename; 61 struct evm_ima_xattr_data *xattr_value; 62 int xattr_len; 63 const struct modsig *modsig; 64 const char *violation; 65 const void *buf; 66 int buf_len; 67 }; 68 69 /* IMA template field data definition */ 70 struct ima_field_data { 71 u8 *data; 72 u32 len; 73 }; 74 75 /* IMA template field definition */ 76 struct ima_template_field { 77 const char field_id[IMA_TEMPLATE_FIELD_ID_MAX_LEN]; 78 int (*field_init)(struct ima_event_data *event_data, 79 struct ima_field_data *field_data); 80 void (*field_show)(struct seq_file *m, enum ima_show_type show, 81 struct ima_field_data *field_data); 82 }; 83 84 /* IMA template descriptor definition */ 85 struct ima_template_desc { 86 struct list_head list; 87 char *name; 88 char *fmt; 89 int num_fields; 90 const struct ima_template_field **fields; 91 }; 92 93 struct ima_template_entry { 94 int pcr; 95 u8 digest[TPM_DIGEST_SIZE]; /* sha1 or md5 measurement hash */ 96 struct ima_template_desc *template_desc; /* template descriptor */ 97 u32 template_data_len; 98 struct ima_field_data template_data[0]; /* template related data */ 99 }; 100 101 struct ima_queue_entry { 102 struct hlist_node hnext; /* place in hash collision list */ 103 struct list_head later; /* place in ima_measurements list */ 104 struct ima_template_entry *entry; 105 }; 106 extern struct list_head ima_measurements; /* list of all measurements */ 107 108 /* Some details preceding the binary serialized measurement list */ 109 struct ima_kexec_hdr { 110 u16 version; 111 u16 _reserved0; 112 u32 _reserved1; 113 u64 buffer_size; 114 u64 count; 115 }; 116 117 extern const int read_idmap[]; 118 119 #ifdef CONFIG_HAVE_IMA_KEXEC 120 void ima_load_kexec_buffer(void); 121 #else 122 static inline void ima_load_kexec_buffer(void) {} 123 #endif /* CONFIG_HAVE_IMA_KEXEC */ 124 125 /* 126 * The default binary_runtime_measurements list format is defined as the 127 * platform native format. The canonical format is defined as little-endian. 128 */ 129 extern bool ima_canonical_fmt; 130 131 /* Internal IMA function definitions */ 132 int ima_init(void); 133 int ima_fs_init(void); 134 int ima_add_template_entry(struct ima_template_entry *entry, int violation, 135 const char *op, struct inode *inode, 136 const unsigned char *filename); 137 int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash); 138 int ima_calc_buffer_hash(const void *buf, loff_t len, 139 struct ima_digest_data *hash); 140 int ima_calc_field_array_hash(struct ima_field_data *field_data, 141 struct ima_template_desc *desc, int num_fields, 142 struct ima_digest_data *hash); 143 int __init ima_calc_boot_aggregate(struct ima_digest_data *hash); 144 void ima_add_violation(struct file *file, const unsigned char *filename, 145 struct integrity_iint_cache *iint, 146 const char *op, const char *cause); 147 int ima_init_crypto(void); 148 void ima_putc(struct seq_file *m, void *data, int datalen); 149 void ima_print_digest(struct seq_file *m, u8 *digest, u32 size); 150 int template_desc_init_fields(const char *template_fmt, 151 const struct ima_template_field ***fields, 152 int *num_fields); 153 struct ima_template_desc *ima_template_desc_current(void); 154 struct ima_template_desc *lookup_template_desc(const char *name); 155 bool ima_template_has_modsig(const struct ima_template_desc *ima_template); 156 int ima_restore_measurement_entry(struct ima_template_entry *entry); 157 int ima_restore_measurement_list(loff_t bufsize, void *buf); 158 int ima_measurements_show(struct seq_file *m, void *v); 159 unsigned long ima_get_binary_runtime_size(void); 160 int ima_init_template(void); 161 void ima_init_template_list(void); 162 int __init ima_init_digests(void); 163 int ima_lsm_policy_change(struct notifier_block *nb, unsigned long event, 164 void *lsm_data); 165 166 /* 167 * used to protect h_table and sha_table 168 */ 169 extern spinlock_t ima_queue_lock; 170 171 struct ima_h_table { 172 atomic_long_t len; /* number of stored measurements in the list */ 173 atomic_long_t violations; 174 struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE]; 175 }; 176 extern struct ima_h_table ima_htable; 177 178 static inline unsigned long ima_hash_key(u8 *digest) 179 { 180 return hash_long(*digest, IMA_HASH_BITS); 181 } 182 183 #define __ima_hooks(hook) \ 184 hook(NONE) \ 185 hook(FILE_CHECK) \ 186 hook(MMAP_CHECK) \ 187 hook(BPRM_CHECK) \ 188 hook(CREDS_CHECK) \ 189 hook(POST_SETATTR) \ 190 hook(MODULE_CHECK) \ 191 hook(FIRMWARE_CHECK) \ 192 hook(KEXEC_KERNEL_CHECK) \ 193 hook(KEXEC_INITRAMFS_CHECK) \ 194 hook(POLICY_CHECK) \ 195 hook(KEXEC_CMDLINE) \ 196 hook(MAX_CHECK) 197 #define __ima_hook_enumify(ENUM) ENUM, 198 199 enum ima_hooks { 200 __ima_hooks(__ima_hook_enumify) 201 }; 202 203 extern const char *const func_tokens[]; 204 205 struct modsig; 206 207 /* LIM API function definitions */ 208 int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid, 209 int mask, enum ima_hooks func, int *pcr, 210 struct ima_template_desc **template_desc); 211 int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func); 212 int ima_collect_measurement(struct integrity_iint_cache *iint, 213 struct file *file, void *buf, loff_t size, 214 enum hash_algo algo, struct modsig *modsig); 215 void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file, 216 const unsigned char *filename, 217 struct evm_ima_xattr_data *xattr_value, 218 int xattr_len, const struct modsig *modsig, int pcr, 219 struct ima_template_desc *template_desc); 220 void process_buffer_measurement(const void *buf, int size, 221 const char *eventname, enum ima_hooks func, 222 int pcr); 223 void ima_audit_measurement(struct integrity_iint_cache *iint, 224 const unsigned char *filename); 225 int ima_alloc_init_template(struct ima_event_data *event_data, 226 struct ima_template_entry **entry, 227 struct ima_template_desc *template_desc); 228 int ima_store_template(struct ima_template_entry *entry, int violation, 229 struct inode *inode, 230 const unsigned char *filename, int pcr); 231 void ima_free_template_entry(struct ima_template_entry *entry); 232 const char *ima_d_path(const struct path *path, char **pathbuf, char *filename); 233 234 /* IMA policy related functions */ 235 int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid, 236 enum ima_hooks func, int mask, int flags, int *pcr, 237 struct ima_template_desc **template_desc); 238 void ima_init_policy(void); 239 void ima_update_policy(void); 240 void ima_update_policy_flag(void); 241 ssize_t ima_parse_add_rule(char *); 242 void ima_delete_rules(void); 243 int ima_check_policy(void); 244 void *ima_policy_start(struct seq_file *m, loff_t *pos); 245 void *ima_policy_next(struct seq_file *m, void *v, loff_t *pos); 246 void ima_policy_stop(struct seq_file *m, void *v); 247 int ima_policy_show(struct seq_file *m, void *v); 248 249 /* Appraise integrity measurements */ 250 #define IMA_APPRAISE_ENFORCE 0x01 251 #define IMA_APPRAISE_FIX 0x02 252 #define IMA_APPRAISE_LOG 0x04 253 #define IMA_APPRAISE_MODULES 0x08 254 #define IMA_APPRAISE_FIRMWARE 0x10 255 #define IMA_APPRAISE_POLICY 0x20 256 #define IMA_APPRAISE_KEXEC 0x40 257 258 #ifdef CONFIG_IMA_APPRAISE 259 int ima_check_blacklist(struct integrity_iint_cache *iint, 260 const struct modsig *modsig, int pcr); 261 int ima_appraise_measurement(enum ima_hooks func, 262 struct integrity_iint_cache *iint, 263 struct file *file, const unsigned char *filename, 264 struct evm_ima_xattr_data *xattr_value, 265 int xattr_len, const struct modsig *modsig); 266 int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func); 267 void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file); 268 enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint, 269 enum ima_hooks func); 270 enum hash_algo ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, 271 int xattr_len); 272 int ima_read_xattr(struct dentry *dentry, 273 struct evm_ima_xattr_data **xattr_value); 274 275 #else 276 static inline int ima_check_blacklist(struct integrity_iint_cache *iint, 277 const struct modsig *modsig, int pcr) 278 { 279 return 0; 280 } 281 282 static inline int ima_appraise_measurement(enum ima_hooks func, 283 struct integrity_iint_cache *iint, 284 struct file *file, 285 const unsigned char *filename, 286 struct evm_ima_xattr_data *xattr_value, 287 int xattr_len, 288 const struct modsig *modsig) 289 { 290 return INTEGRITY_UNKNOWN; 291 } 292 293 static inline int ima_must_appraise(struct inode *inode, int mask, 294 enum ima_hooks func) 295 { 296 return 0; 297 } 298 299 static inline void ima_update_xattr(struct integrity_iint_cache *iint, 300 struct file *file) 301 { 302 } 303 304 static inline enum integrity_status ima_get_cache_status(struct integrity_iint_cache 305 *iint, 306 enum ima_hooks func) 307 { 308 return INTEGRITY_UNKNOWN; 309 } 310 311 static inline enum hash_algo 312 ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len) 313 { 314 return ima_hash_algo; 315 } 316 317 static inline int ima_read_xattr(struct dentry *dentry, 318 struct evm_ima_xattr_data **xattr_value) 319 { 320 return 0; 321 } 322 323 #endif /* CONFIG_IMA_APPRAISE */ 324 325 #ifdef CONFIG_IMA_APPRAISE_MODSIG 326 bool ima_hook_supports_modsig(enum ima_hooks func); 327 int ima_read_modsig(enum ima_hooks func, const void *buf, loff_t buf_len, 328 struct modsig **modsig); 329 void ima_collect_modsig(struct modsig *modsig, const void *buf, loff_t size); 330 int ima_get_modsig_digest(const struct modsig *modsig, enum hash_algo *algo, 331 const u8 **digest, u32 *digest_size); 332 int ima_get_raw_modsig(const struct modsig *modsig, const void **data, 333 u32 *data_len); 334 void ima_free_modsig(struct modsig *modsig); 335 #else 336 static inline bool ima_hook_supports_modsig(enum ima_hooks func) 337 { 338 return false; 339 } 340 341 static inline int ima_read_modsig(enum ima_hooks func, const void *buf, 342 loff_t buf_len, struct modsig **modsig) 343 { 344 return -EOPNOTSUPP; 345 } 346 347 static inline void ima_collect_modsig(struct modsig *modsig, const void *buf, 348 loff_t size) 349 { 350 } 351 352 static inline int ima_get_modsig_digest(const struct modsig *modsig, 353 enum hash_algo *algo, const u8 **digest, 354 u32 *digest_size) 355 { 356 return -EOPNOTSUPP; 357 } 358 359 static inline int ima_get_raw_modsig(const struct modsig *modsig, 360 const void **data, u32 *data_len) 361 { 362 return -EOPNOTSUPP; 363 } 364 365 static inline void ima_free_modsig(struct modsig *modsig) 366 { 367 } 368 #endif /* CONFIG_IMA_APPRAISE_MODSIG */ 369 370 /* LSM based policy rules require audit */ 371 #ifdef CONFIG_IMA_LSM_RULES 372 373 #define security_filter_rule_init security_audit_rule_init 374 #define security_filter_rule_match security_audit_rule_match 375 376 #else 377 378 static inline int security_filter_rule_init(u32 field, u32 op, char *rulestr, 379 void **lsmrule) 380 { 381 return -EINVAL; 382 } 383 384 static inline int security_filter_rule_match(u32 secid, u32 field, u32 op, 385 void *lsmrule) 386 { 387 return -EINVAL; 388 } 389 #endif /* CONFIG_IMA_LSM_RULES */ 390 391 #ifdef CONFIG_IMA_READ_POLICY 392 #define POLICY_FILE_FLAGS (S_IWUSR | S_IRUSR) 393 #else 394 #define POLICY_FILE_FLAGS S_IWUSR 395 #endif /* CONFIG_IMA_READ_POLICY */ 396 397 #endif /* __LINUX_IMA_H */ 398