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[0]; /* 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 *lookup_template_desc(const char *name); 160 bool ima_template_has_modsig(const struct ima_template_desc *ima_template); 161 int ima_restore_measurement_entry(struct ima_template_entry *entry); 162 int ima_restore_measurement_list(loff_t bufsize, void *buf); 163 int ima_measurements_show(struct seq_file *m, void *v); 164 unsigned long ima_get_binary_runtime_size(void); 165 int ima_init_template(void); 166 void ima_init_template_list(void); 167 int __init ima_init_digests(void); 168 int ima_lsm_policy_change(struct notifier_block *nb, unsigned long event, 169 void *lsm_data); 170 171 /* 172 * used to protect h_table and sha_table 173 */ 174 extern spinlock_t ima_queue_lock; 175 176 struct ima_h_table { 177 atomic_long_t len; /* number of stored measurements in the list */ 178 atomic_long_t violations; 179 struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE]; 180 }; 181 extern struct ima_h_table ima_htable; 182 183 static inline unsigned int ima_hash_key(u8 *digest) 184 { 185 /* there is no point in taking a hash of part of a digest */ 186 return (digest[0] | digest[1] << 8) % IMA_MEASURE_HTABLE_SIZE; 187 } 188 189 #define __ima_hooks(hook) \ 190 hook(NONE, none) \ 191 hook(FILE_CHECK, file) \ 192 hook(MMAP_CHECK, mmap) \ 193 hook(BPRM_CHECK, bprm) \ 194 hook(CREDS_CHECK, creds) \ 195 hook(POST_SETATTR, post_setattr) \ 196 hook(MODULE_CHECK, module) \ 197 hook(FIRMWARE_CHECK, firmware) \ 198 hook(KEXEC_KERNEL_CHECK, kexec_kernel) \ 199 hook(KEXEC_INITRAMFS_CHECK, kexec_initramfs) \ 200 hook(POLICY_CHECK, policy) \ 201 hook(KEXEC_CMDLINE, kexec_cmdline) \ 202 hook(KEY_CHECK, key) \ 203 hook(MAX_CHECK, none) 204 205 #define __ima_hook_enumify(ENUM, str) ENUM, 206 #define __ima_stringify(arg) (#arg) 207 #define __ima_hook_measuring_stringify(ENUM, str) \ 208 (__ima_stringify(measuring_ ##str)), 209 210 enum ima_hooks { 211 __ima_hooks(__ima_hook_enumify) 212 }; 213 214 static const char * const ima_hooks_measure_str[] = { 215 __ima_hooks(__ima_hook_measuring_stringify) 216 }; 217 218 static inline const char *func_measure_str(enum ima_hooks func) 219 { 220 if (func >= MAX_CHECK) 221 return ima_hooks_measure_str[NONE]; 222 223 return ima_hooks_measure_str[func]; 224 } 225 226 extern const char *const func_tokens[]; 227 228 struct modsig; 229 230 #ifdef CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS 231 /* 232 * To track keys that need to be measured. 233 */ 234 struct ima_key_entry { 235 struct list_head list; 236 void *payload; 237 size_t payload_len; 238 char *keyring_name; 239 }; 240 void ima_init_key_queue(void); 241 bool ima_should_queue_key(void); 242 bool ima_queue_key(struct key *keyring, const void *payload, 243 size_t payload_len); 244 void ima_process_queued_keys(void); 245 #else 246 static inline void ima_init_key_queue(void) {} 247 static inline bool ima_should_queue_key(void) { return false; } 248 static inline bool ima_queue_key(struct key *keyring, 249 const void *payload, 250 size_t payload_len) { return false; } 251 static inline void ima_process_queued_keys(void) {} 252 #endif /* CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS */ 253 254 /* LIM API function definitions */ 255 int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid, 256 int mask, enum ima_hooks func, int *pcr, 257 struct ima_template_desc **template_desc, 258 const char *keyring); 259 int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func); 260 int ima_collect_measurement(struct integrity_iint_cache *iint, 261 struct file *file, void *buf, loff_t size, 262 enum hash_algo algo, struct modsig *modsig); 263 void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file, 264 const unsigned char *filename, 265 struct evm_ima_xattr_data *xattr_value, 266 int xattr_len, const struct modsig *modsig, int pcr, 267 struct ima_template_desc *template_desc); 268 void process_buffer_measurement(struct inode *inode, const void *buf, int size, 269 const char *eventname, enum ima_hooks func, 270 int pcr, const char *keyring); 271 void ima_audit_measurement(struct integrity_iint_cache *iint, 272 const unsigned char *filename); 273 int ima_alloc_init_template(struct ima_event_data *event_data, 274 struct ima_template_entry **entry, 275 struct ima_template_desc *template_desc); 276 int ima_store_template(struct ima_template_entry *entry, int violation, 277 struct inode *inode, 278 const unsigned char *filename, int pcr); 279 void ima_free_template_entry(struct ima_template_entry *entry); 280 const char *ima_d_path(const struct path *path, char **pathbuf, char *filename); 281 282 /* IMA policy related functions */ 283 int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid, 284 enum ima_hooks func, int mask, int flags, int *pcr, 285 struct ima_template_desc **template_desc, 286 const char *keyring); 287 void ima_init_policy(void); 288 void ima_update_policy(void); 289 void ima_update_policy_flag(void); 290 ssize_t ima_parse_add_rule(char *); 291 void ima_delete_rules(void); 292 int ima_check_policy(void); 293 void *ima_policy_start(struct seq_file *m, loff_t *pos); 294 void *ima_policy_next(struct seq_file *m, void *v, loff_t *pos); 295 void ima_policy_stop(struct seq_file *m, void *v); 296 int ima_policy_show(struct seq_file *m, void *v); 297 298 /* Appraise integrity measurements */ 299 #define IMA_APPRAISE_ENFORCE 0x01 300 #define IMA_APPRAISE_FIX 0x02 301 #define IMA_APPRAISE_LOG 0x04 302 #define IMA_APPRAISE_MODULES 0x08 303 #define IMA_APPRAISE_FIRMWARE 0x10 304 #define IMA_APPRAISE_POLICY 0x20 305 #define IMA_APPRAISE_KEXEC 0x40 306 307 #ifdef CONFIG_IMA_APPRAISE 308 int ima_check_blacklist(struct integrity_iint_cache *iint, 309 const struct modsig *modsig, int pcr); 310 int ima_appraise_measurement(enum ima_hooks func, 311 struct integrity_iint_cache *iint, 312 struct file *file, const unsigned char *filename, 313 struct evm_ima_xattr_data *xattr_value, 314 int xattr_len, const struct modsig *modsig); 315 int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func); 316 void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file); 317 enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint, 318 enum ima_hooks func); 319 enum hash_algo ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, 320 int xattr_len); 321 int ima_read_xattr(struct dentry *dentry, 322 struct evm_ima_xattr_data **xattr_value); 323 324 #else 325 static inline int ima_check_blacklist(struct integrity_iint_cache *iint, 326 const struct modsig *modsig, int pcr) 327 { 328 return 0; 329 } 330 331 static inline int ima_appraise_measurement(enum ima_hooks func, 332 struct integrity_iint_cache *iint, 333 struct file *file, 334 const unsigned char *filename, 335 struct evm_ima_xattr_data *xattr_value, 336 int xattr_len, 337 const struct modsig *modsig) 338 { 339 return INTEGRITY_UNKNOWN; 340 } 341 342 static inline int ima_must_appraise(struct inode *inode, int mask, 343 enum ima_hooks func) 344 { 345 return 0; 346 } 347 348 static inline void ima_update_xattr(struct integrity_iint_cache *iint, 349 struct file *file) 350 { 351 } 352 353 static inline enum integrity_status ima_get_cache_status(struct integrity_iint_cache 354 *iint, 355 enum ima_hooks func) 356 { 357 return INTEGRITY_UNKNOWN; 358 } 359 360 static inline enum hash_algo 361 ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len) 362 { 363 return ima_hash_algo; 364 } 365 366 static inline int ima_read_xattr(struct dentry *dentry, 367 struct evm_ima_xattr_data **xattr_value) 368 { 369 return 0; 370 } 371 372 #endif /* CONFIG_IMA_APPRAISE */ 373 374 #ifdef CONFIG_IMA_APPRAISE_MODSIG 375 int ima_read_modsig(enum ima_hooks func, const void *buf, loff_t buf_len, 376 struct modsig **modsig); 377 void ima_collect_modsig(struct modsig *modsig, const void *buf, loff_t size); 378 int ima_get_modsig_digest(const struct modsig *modsig, enum hash_algo *algo, 379 const u8 **digest, u32 *digest_size); 380 int ima_get_raw_modsig(const struct modsig *modsig, const void **data, 381 u32 *data_len); 382 void ima_free_modsig(struct modsig *modsig); 383 #else 384 static inline int ima_read_modsig(enum ima_hooks func, const void *buf, 385 loff_t buf_len, struct modsig **modsig) 386 { 387 return -EOPNOTSUPP; 388 } 389 390 static inline void ima_collect_modsig(struct modsig *modsig, const void *buf, 391 loff_t size) 392 { 393 } 394 395 static inline int ima_get_modsig_digest(const struct modsig *modsig, 396 enum hash_algo *algo, const u8 **digest, 397 u32 *digest_size) 398 { 399 return -EOPNOTSUPP; 400 } 401 402 static inline int ima_get_raw_modsig(const struct modsig *modsig, 403 const void **data, u32 *data_len) 404 { 405 return -EOPNOTSUPP; 406 } 407 408 static inline void ima_free_modsig(struct modsig *modsig) 409 { 410 } 411 #endif /* CONFIG_IMA_APPRAISE_MODSIG */ 412 413 /* LSM based policy rules require audit */ 414 #ifdef CONFIG_IMA_LSM_RULES 415 416 #define ima_filter_rule_init security_audit_rule_init 417 #define ima_filter_rule_free security_audit_rule_free 418 #define ima_filter_rule_match security_audit_rule_match 419 420 #else 421 422 static inline int ima_filter_rule_init(u32 field, u32 op, char *rulestr, 423 void **lsmrule) 424 { 425 return -EINVAL; 426 } 427 428 static inline void ima_filter_rule_free(void *lsmrule) 429 { 430 } 431 432 static inline int ima_filter_rule_match(u32 secid, u32 field, u32 op, 433 void *lsmrule) 434 { 435 return -EINVAL; 436 } 437 #endif /* CONFIG_IMA_LSM_RULES */ 438 439 #ifdef CONFIG_IMA_READ_POLICY 440 #define POLICY_FILE_FLAGS (S_IWUSR | S_IRUSR) 441 #else 442 #define POLICY_FILE_FLAGS S_IWUSR 443 #endif /* CONFIG_IMA_READ_POLICY */ 444 445 #endif /* __LINUX_IMA_H */ 446