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, TPM_PCR10 = 10 }; 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 10 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 #define NR_BANKS(chip) ((chip != NULL) ? chip->nr_allocated_banks : 0) 49 50 /* current content of the policy */ 51 extern int ima_policy_flag; 52 53 /* set during initialization */ 54 extern int ima_hash_algo; 55 extern int ima_sha1_idx __ro_after_init; 56 extern int ima_hash_algo_idx __ro_after_init; 57 extern int ima_extra_slots __ro_after_init; 58 extern int ima_appraise; 59 extern struct tpm_chip *ima_tpm_chip; 60 extern const char boot_aggregate_name[]; 61 62 /* IMA event related data */ 63 struct ima_event_data { 64 struct integrity_iint_cache *iint; 65 struct file *file; 66 const unsigned char *filename; 67 struct evm_ima_xattr_data *xattr_value; 68 int xattr_len; 69 const struct modsig *modsig; 70 const char *violation; 71 const void *buf; 72 int buf_len; 73 }; 74 75 /* IMA template field data definition */ 76 struct ima_field_data { 77 u8 *data; 78 u32 len; 79 }; 80 81 /* IMA template field definition */ 82 struct ima_template_field { 83 const char field_id[IMA_TEMPLATE_FIELD_ID_MAX_LEN]; 84 int (*field_init)(struct ima_event_data *event_data, 85 struct ima_field_data *field_data); 86 void (*field_show)(struct seq_file *m, enum ima_show_type show, 87 struct ima_field_data *field_data); 88 }; 89 90 /* IMA template descriptor definition */ 91 struct ima_template_desc { 92 struct list_head list; 93 char *name; 94 char *fmt; 95 int num_fields; 96 const struct ima_template_field **fields; 97 }; 98 99 struct ima_template_entry { 100 int pcr; 101 struct tpm_digest *digests; 102 struct ima_template_desc *template_desc; /* template descriptor */ 103 u32 template_data_len; 104 struct ima_field_data template_data[]; /* template related data */ 105 }; 106 107 struct ima_queue_entry { 108 struct hlist_node hnext; /* place in hash collision list */ 109 struct list_head later; /* place in ima_measurements list */ 110 struct ima_template_entry *entry; 111 }; 112 extern struct list_head ima_measurements; /* list of all measurements */ 113 114 /* Some details preceding the binary serialized measurement list */ 115 struct ima_kexec_hdr { 116 u16 version; 117 u16 _reserved0; 118 u32 _reserved1; 119 u64 buffer_size; 120 u64 count; 121 }; 122 123 extern const int read_idmap[]; 124 125 #ifdef CONFIG_HAVE_IMA_KEXEC 126 void ima_load_kexec_buffer(void); 127 #else 128 static inline void ima_load_kexec_buffer(void) {} 129 #endif /* CONFIG_HAVE_IMA_KEXEC */ 130 131 /* 132 * The default binary_runtime_measurements list format is defined as the 133 * platform native format. The canonical format is defined as little-endian. 134 */ 135 extern bool ima_canonical_fmt; 136 137 /* Internal IMA function definitions */ 138 int ima_init(void); 139 int ima_fs_init(void); 140 int ima_add_template_entry(struct ima_template_entry *entry, int violation, 141 const char *op, struct inode *inode, 142 const unsigned char *filename); 143 int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash); 144 int ima_calc_buffer_hash(const void *buf, loff_t len, 145 struct ima_digest_data *hash); 146 int ima_calc_field_array_hash(struct ima_field_data *field_data, 147 struct ima_template_entry *entry); 148 int ima_calc_boot_aggregate(struct ima_digest_data *hash); 149 void ima_add_violation(struct file *file, const unsigned char *filename, 150 struct integrity_iint_cache *iint, 151 const char *op, const char *cause); 152 int ima_init_crypto(void); 153 void ima_putc(struct seq_file *m, void *data, int datalen); 154 void ima_print_digest(struct seq_file *m, u8 *digest, u32 size); 155 int template_desc_init_fields(const char *template_fmt, 156 const struct ima_template_field ***fields, 157 int *num_fields); 158 struct ima_template_desc *ima_template_desc_current(void); 159 struct ima_template_desc *ima_template_desc_buf(void); 160 struct ima_template_desc *lookup_template_desc(const char *name); 161 bool ima_template_has_modsig(const struct ima_template_desc *ima_template); 162 int ima_restore_measurement_entry(struct ima_template_entry *entry); 163 int ima_restore_measurement_list(loff_t bufsize, void *buf); 164 int ima_measurements_show(struct seq_file *m, void *v); 165 unsigned long ima_get_binary_runtime_size(void); 166 int ima_init_template(void); 167 void ima_init_template_list(void); 168 int __init ima_init_digests(void); 169 int ima_lsm_policy_change(struct notifier_block *nb, unsigned long event, 170 void *lsm_data); 171 172 /* 173 * used to protect h_table and sha_table 174 */ 175 extern spinlock_t ima_queue_lock; 176 177 struct ima_h_table { 178 atomic_long_t len; /* number of stored measurements in the list */ 179 atomic_long_t violations; 180 struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE]; 181 }; 182 extern struct ima_h_table ima_htable; 183 184 static inline unsigned int ima_hash_key(u8 *digest) 185 { 186 /* there is no point in taking a hash of part of a digest */ 187 return (digest[0] | digest[1] << 8) % IMA_MEASURE_HTABLE_SIZE; 188 } 189 190 #define __ima_hooks(hook) \ 191 hook(NONE, none) \ 192 hook(FILE_CHECK, file) \ 193 hook(MMAP_CHECK, mmap) \ 194 hook(BPRM_CHECK, bprm) \ 195 hook(CREDS_CHECK, creds) \ 196 hook(POST_SETATTR, post_setattr) \ 197 hook(MODULE_CHECK, module) \ 198 hook(FIRMWARE_CHECK, firmware) \ 199 hook(KEXEC_KERNEL_CHECK, kexec_kernel) \ 200 hook(KEXEC_INITRAMFS_CHECK, kexec_initramfs) \ 201 hook(POLICY_CHECK, policy) \ 202 hook(KEXEC_CMDLINE, kexec_cmdline) \ 203 hook(KEY_CHECK, key) \ 204 hook(MAX_CHECK, none) 205 206 #define __ima_hook_enumify(ENUM, str) ENUM, 207 #define __ima_stringify(arg) (#arg) 208 #define __ima_hook_measuring_stringify(ENUM, str) \ 209 (__ima_stringify(measuring_ ##str)), 210 211 enum ima_hooks { 212 __ima_hooks(__ima_hook_enumify) 213 }; 214 215 static const char * const ima_hooks_measure_str[] = { 216 __ima_hooks(__ima_hook_measuring_stringify) 217 }; 218 219 static inline const char *func_measure_str(enum ima_hooks func) 220 { 221 if (func >= MAX_CHECK) 222 return ima_hooks_measure_str[NONE]; 223 224 return ima_hooks_measure_str[func]; 225 } 226 227 extern const char *const func_tokens[]; 228 229 struct modsig; 230 231 #ifdef CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS 232 /* 233 * To track keys that need to be measured. 234 */ 235 struct ima_key_entry { 236 struct list_head list; 237 void *payload; 238 size_t payload_len; 239 char *keyring_name; 240 }; 241 void ima_init_key_queue(void); 242 bool ima_should_queue_key(void); 243 bool ima_queue_key(struct key *keyring, const void *payload, 244 size_t payload_len); 245 void ima_process_queued_keys(void); 246 #else 247 static inline void ima_init_key_queue(void) {} 248 static inline bool ima_should_queue_key(void) { return false; } 249 static inline bool ima_queue_key(struct key *keyring, 250 const void *payload, 251 size_t payload_len) { return false; } 252 static inline void ima_process_queued_keys(void) {} 253 #endif /* CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS */ 254 255 /* LIM API function definitions */ 256 int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid, 257 int mask, enum ima_hooks func, int *pcr, 258 struct ima_template_desc **template_desc, 259 const char *keyring); 260 int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func); 261 int ima_collect_measurement(struct integrity_iint_cache *iint, 262 struct file *file, void *buf, loff_t size, 263 enum hash_algo algo, struct modsig *modsig); 264 void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file, 265 const unsigned char *filename, 266 struct evm_ima_xattr_data *xattr_value, 267 int xattr_len, const struct modsig *modsig, int pcr, 268 struct ima_template_desc *template_desc); 269 void process_buffer_measurement(struct inode *inode, const void *buf, int size, 270 const char *eventname, enum ima_hooks func, 271 int pcr, const char *keyring); 272 void ima_audit_measurement(struct integrity_iint_cache *iint, 273 const unsigned char *filename); 274 int ima_alloc_init_template(struct ima_event_data *event_data, 275 struct ima_template_entry **entry, 276 struct ima_template_desc *template_desc); 277 int ima_store_template(struct ima_template_entry *entry, int violation, 278 struct inode *inode, 279 const unsigned char *filename, int pcr); 280 void ima_free_template_entry(struct ima_template_entry *entry); 281 const char *ima_d_path(const struct path *path, char **pathbuf, char *filename); 282 283 /* IMA policy related functions */ 284 int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid, 285 enum ima_hooks func, int mask, int flags, int *pcr, 286 struct ima_template_desc **template_desc, 287 const char *keyring); 288 void ima_init_policy(void); 289 void ima_update_policy(void); 290 void ima_update_policy_flag(void); 291 ssize_t ima_parse_add_rule(char *); 292 void ima_delete_rules(void); 293 int ima_check_policy(void); 294 void *ima_policy_start(struct seq_file *m, loff_t *pos); 295 void *ima_policy_next(struct seq_file *m, void *v, loff_t *pos); 296 void ima_policy_stop(struct seq_file *m, void *v); 297 int ima_policy_show(struct seq_file *m, void *v); 298 299 /* Appraise integrity measurements */ 300 #define IMA_APPRAISE_ENFORCE 0x01 301 #define IMA_APPRAISE_FIX 0x02 302 #define IMA_APPRAISE_LOG 0x04 303 #define IMA_APPRAISE_MODULES 0x08 304 #define IMA_APPRAISE_FIRMWARE 0x10 305 #define IMA_APPRAISE_POLICY 0x20 306 #define IMA_APPRAISE_KEXEC 0x40 307 308 #ifdef CONFIG_IMA_APPRAISE 309 int ima_check_blacklist(struct integrity_iint_cache *iint, 310 const struct modsig *modsig, int pcr); 311 int ima_appraise_measurement(enum ima_hooks func, 312 struct integrity_iint_cache *iint, 313 struct file *file, const unsigned char *filename, 314 struct evm_ima_xattr_data *xattr_value, 315 int xattr_len, const struct modsig *modsig); 316 int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func); 317 void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file); 318 enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint, 319 enum ima_hooks func); 320 enum hash_algo ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, 321 int xattr_len); 322 int ima_read_xattr(struct dentry *dentry, 323 struct evm_ima_xattr_data **xattr_value); 324 325 #else 326 static inline int ima_check_blacklist(struct integrity_iint_cache *iint, 327 const struct modsig *modsig, int pcr) 328 { 329 return 0; 330 } 331 332 static inline int ima_appraise_measurement(enum ima_hooks func, 333 struct integrity_iint_cache *iint, 334 struct file *file, 335 const unsigned char *filename, 336 struct evm_ima_xattr_data *xattr_value, 337 int xattr_len, 338 const struct modsig *modsig) 339 { 340 return INTEGRITY_UNKNOWN; 341 } 342 343 static inline int ima_must_appraise(struct inode *inode, int mask, 344 enum ima_hooks func) 345 { 346 return 0; 347 } 348 349 static inline void ima_update_xattr(struct integrity_iint_cache *iint, 350 struct file *file) 351 { 352 } 353 354 static inline enum integrity_status ima_get_cache_status(struct integrity_iint_cache 355 *iint, 356 enum ima_hooks func) 357 { 358 return INTEGRITY_UNKNOWN; 359 } 360 361 static inline enum hash_algo 362 ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len) 363 { 364 return ima_hash_algo; 365 } 366 367 static inline int ima_read_xattr(struct dentry *dentry, 368 struct evm_ima_xattr_data **xattr_value) 369 { 370 return 0; 371 } 372 373 #endif /* CONFIG_IMA_APPRAISE */ 374 375 #ifdef CONFIG_IMA_APPRAISE_MODSIG 376 int ima_read_modsig(enum ima_hooks func, const void *buf, loff_t buf_len, 377 struct modsig **modsig); 378 void ima_collect_modsig(struct modsig *modsig, const void *buf, loff_t size); 379 int ima_get_modsig_digest(const struct modsig *modsig, enum hash_algo *algo, 380 const u8 **digest, u32 *digest_size); 381 int ima_get_raw_modsig(const struct modsig *modsig, const void **data, 382 u32 *data_len); 383 void ima_free_modsig(struct modsig *modsig); 384 #else 385 static inline int ima_read_modsig(enum ima_hooks func, const void *buf, 386 loff_t buf_len, struct modsig **modsig) 387 { 388 return -EOPNOTSUPP; 389 } 390 391 static inline void ima_collect_modsig(struct modsig *modsig, const void *buf, 392 loff_t size) 393 { 394 } 395 396 static inline int ima_get_modsig_digest(const struct modsig *modsig, 397 enum hash_algo *algo, const u8 **digest, 398 u32 *digest_size) 399 { 400 return -EOPNOTSUPP; 401 } 402 403 static inline int ima_get_raw_modsig(const struct modsig *modsig, 404 const void **data, u32 *data_len) 405 { 406 return -EOPNOTSUPP; 407 } 408 409 static inline void ima_free_modsig(struct modsig *modsig) 410 { 411 } 412 #endif /* CONFIG_IMA_APPRAISE_MODSIG */ 413 414 /* LSM based policy rules require audit */ 415 #ifdef CONFIG_IMA_LSM_RULES 416 417 #define ima_filter_rule_init security_audit_rule_init 418 #define ima_filter_rule_free security_audit_rule_free 419 #define ima_filter_rule_match security_audit_rule_match 420 421 #else 422 423 static inline int ima_filter_rule_init(u32 field, u32 op, char *rulestr, 424 void **lsmrule) 425 { 426 return -EINVAL; 427 } 428 429 static inline void ima_filter_rule_free(void *lsmrule) 430 { 431 } 432 433 static inline int ima_filter_rule_match(u32 secid, u32 field, u32 op, 434 void *lsmrule) 435 { 436 return -EINVAL; 437 } 438 #endif /* CONFIG_IMA_LSM_RULES */ 439 440 #ifdef CONFIG_IMA_READ_POLICY 441 #define POLICY_FILE_FLAGS (S_IWUSR | S_IRUSR) 442 #else 443 #define POLICY_FILE_FLAGS S_IWUSR 444 #endif /* CONFIG_IMA_READ_POLICY */ 445 446 #endif /* __LINUX_IMA_H */ 447