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 enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_BINARY_NO_FIELD_LEN, 28 IMA_SHOW_BINARY_OLD_STRING_FMT, IMA_SHOW_ASCII }; 29 enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8, TPM_PCR10 = 10 }; 30 31 /* digest size for IMA, fits SHA1 or MD5 */ 32 #define IMA_DIGEST_SIZE SHA1_DIGEST_SIZE 33 #define IMA_EVENT_NAME_LEN_MAX 255 34 35 #define IMA_HASH_BITS 10 36 #define IMA_MEASURE_HTABLE_SIZE (1 << IMA_HASH_BITS) 37 38 #define IMA_TEMPLATE_FIELD_ID_MAX_LEN 16 39 #define IMA_TEMPLATE_NUM_FIELDS_MAX 15 40 41 #define IMA_TEMPLATE_IMA_NAME "ima" 42 #define IMA_TEMPLATE_IMA_FMT "d|n" 43 44 #define NR_BANKS(chip) ((chip != NULL) ? chip->nr_allocated_banks : 0) 45 46 /* current content of the policy */ 47 extern int ima_policy_flag; 48 49 /* bitset of digests algorithms allowed in the setxattr hook */ 50 extern atomic_t ima_setxattr_allowed_hash_algorithms; 51 52 /* set during initialization */ 53 extern int ima_hash_algo __ro_after_init; 54 extern int ima_sha1_idx __ro_after_init; 55 extern int ima_hash_algo_idx __ro_after_init; 56 extern int ima_extra_slots __ro_after_init; 57 extern int ima_appraise; 58 extern struct tpm_chip *ima_tpm_chip; 59 extern const char boot_aggregate_name[]; 60 61 /* IMA event related data */ 62 struct ima_event_data { 63 struct integrity_iint_cache *iint; 64 struct file *file; 65 const unsigned char *filename; 66 struct evm_ima_xattr_data *xattr_value; 67 int xattr_len; 68 const struct modsig *modsig; 69 const char *violation; 70 const void *buf; 71 int buf_len; 72 }; 73 74 /* IMA template field data definition */ 75 struct ima_field_data { 76 u8 *data; 77 u32 len; 78 }; 79 80 /* IMA template field definition */ 81 struct ima_template_field { 82 const char field_id[IMA_TEMPLATE_FIELD_ID_MAX_LEN]; 83 int (*field_init)(struct ima_event_data *event_data, 84 struct ima_field_data *field_data); 85 void (*field_show)(struct seq_file *m, enum ima_show_type show, 86 struct ima_field_data *field_data); 87 }; 88 89 /* IMA template descriptor definition */ 90 struct ima_template_desc { 91 struct list_head list; 92 char *name; 93 char *fmt; 94 int num_fields; 95 const struct ima_template_field **fields; 96 }; 97 98 struct ima_template_entry { 99 int pcr; 100 struct tpm_digest *digests; 101 struct ima_template_desc *template_desc; /* template descriptor */ 102 u32 template_data_len; 103 struct ima_field_data template_data[]; /* template related data */ 104 }; 105 106 struct ima_queue_entry { 107 struct hlist_node hnext; /* place in hash collision list */ 108 struct list_head later; /* place in ima_measurements list */ 109 struct ima_template_entry *entry; 110 }; 111 extern struct list_head ima_measurements; /* list of all measurements */ 112 113 /* Some details preceding the binary serialized measurement list */ 114 struct ima_kexec_hdr { 115 u16 version; 116 u16 _reserved0; 117 u32 _reserved1; 118 u64 buffer_size; 119 u64 count; 120 }; 121 122 extern const int read_idmap[]; 123 124 #ifdef CONFIG_HAVE_IMA_KEXEC 125 void ima_load_kexec_buffer(void); 126 #else 127 static inline void ima_load_kexec_buffer(void) {} 128 #endif /* CONFIG_HAVE_IMA_KEXEC */ 129 130 /* 131 * The default binary_runtime_measurements list format is defined as the 132 * platform native format. The canonical format is defined as little-endian. 133 */ 134 extern bool ima_canonical_fmt; 135 136 /* Internal IMA function definitions */ 137 int ima_init(void); 138 int ima_fs_init(void); 139 int ima_add_template_entry(struct ima_template_entry *entry, int violation, 140 const char *op, struct inode *inode, 141 const unsigned char *filename); 142 int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash); 143 int ima_calc_buffer_hash(const void *buf, loff_t len, 144 struct ima_digest_data *hash); 145 int ima_calc_field_array_hash(struct ima_field_data *field_data, 146 struct ima_template_entry *entry); 147 int ima_calc_boot_aggregate(struct ima_digest_data *hash); 148 void ima_add_violation(struct file *file, const unsigned char *filename, 149 struct integrity_iint_cache *iint, 150 const char *op, const char *cause); 151 int ima_init_crypto(void); 152 void ima_putc(struct seq_file *m, void *data, int datalen); 153 void ima_print_digest(struct seq_file *m, u8 *digest, u32 size); 154 int template_desc_init_fields(const char *template_fmt, 155 const struct ima_template_field ***fields, 156 int *num_fields); 157 struct ima_template_desc *ima_template_desc_current(void); 158 struct ima_template_desc *ima_template_desc_buf(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(MMAP_CHECK_REQPROT, mmap_reqprot) \ 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(CRITICAL_DATA, critical_data) \ 205 hook(SETXATTR_CHECK, setxattr_check) \ 206 hook(MAX_CHECK, none) 207 208 #define __ima_hook_enumify(ENUM, str) ENUM, 209 #define __ima_stringify(arg) (#arg) 210 #define __ima_hook_measuring_stringify(ENUM, str) \ 211 (__ima_stringify(measuring_ ##str)), 212 213 enum ima_hooks { 214 __ima_hooks(__ima_hook_enumify) 215 }; 216 217 static const char * const ima_hooks_measure_str[] = { 218 __ima_hooks(__ima_hook_measuring_stringify) 219 }; 220 221 static inline const char *func_measure_str(enum ima_hooks func) 222 { 223 if (func >= MAX_CHECK) 224 return ima_hooks_measure_str[NONE]; 225 226 return ima_hooks_measure_str[func]; 227 } 228 229 extern const char *const func_tokens[]; 230 231 struct modsig; 232 233 #ifdef CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS 234 /* 235 * To track keys that need to be measured. 236 */ 237 struct ima_key_entry { 238 struct list_head list; 239 void *payload; 240 size_t payload_len; 241 char *keyring_name; 242 }; 243 void ima_init_key_queue(void); 244 bool ima_should_queue_key(void); 245 bool ima_queue_key(struct key *keyring, const void *payload, 246 size_t payload_len); 247 void ima_process_queued_keys(void); 248 #else 249 static inline void ima_init_key_queue(void) {} 250 static inline bool ima_should_queue_key(void) { return false; } 251 static inline bool ima_queue_key(struct key *keyring, 252 const void *payload, 253 size_t payload_len) { return false; } 254 static inline void ima_process_queued_keys(void) {} 255 #endif /* CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS */ 256 257 /* LIM API function definitions */ 258 int ima_get_action(struct mnt_idmap *idmap, struct inode *inode, 259 const struct cred *cred, u32 secid, int mask, 260 enum ima_hooks func, int *pcr, 261 struct ima_template_desc **template_desc, 262 const char *func_data, unsigned int *allowed_algos); 263 int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func); 264 int ima_collect_measurement(struct integrity_iint_cache *iint, 265 struct file *file, void *buf, loff_t size, 266 enum hash_algo algo, struct modsig *modsig); 267 void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file, 268 const unsigned char *filename, 269 struct evm_ima_xattr_data *xattr_value, 270 int xattr_len, const struct modsig *modsig, int pcr, 271 struct ima_template_desc *template_desc); 272 int process_buffer_measurement(struct mnt_idmap *idmap, 273 struct inode *inode, const void *buf, int size, 274 const char *eventname, enum ima_hooks func, 275 int pcr, const char *func_data, 276 bool buf_hash, u8 *digest, size_t digest_len); 277 void ima_audit_measurement(struct integrity_iint_cache *iint, 278 const unsigned char *filename); 279 int ima_alloc_init_template(struct ima_event_data *event_data, 280 struct ima_template_entry **entry, 281 struct ima_template_desc *template_desc); 282 int ima_store_template(struct ima_template_entry *entry, int violation, 283 struct inode *inode, 284 const unsigned char *filename, int pcr); 285 void ima_free_template_entry(struct ima_template_entry *entry); 286 const char *ima_d_path(const struct path *path, char **pathbuf, char *filename); 287 288 /* IMA policy related functions */ 289 int ima_match_policy(struct mnt_idmap *idmap, struct inode *inode, 290 const struct cred *cred, u32 secid, enum ima_hooks func, 291 int mask, int flags, int *pcr, 292 struct ima_template_desc **template_desc, 293 const char *func_data, unsigned int *allowed_algos); 294 void ima_init_policy(void); 295 void ima_update_policy(void); 296 void ima_update_policy_flags(void); 297 ssize_t ima_parse_add_rule(char *); 298 void ima_delete_rules(void); 299 int ima_check_policy(void); 300 void *ima_policy_start(struct seq_file *m, loff_t *pos); 301 void *ima_policy_next(struct seq_file *m, void *v, loff_t *pos); 302 void ima_policy_stop(struct seq_file *m, void *v); 303 int ima_policy_show(struct seq_file *m, void *v); 304 305 /* Appraise integrity measurements */ 306 #define IMA_APPRAISE_ENFORCE 0x01 307 #define IMA_APPRAISE_FIX 0x02 308 #define IMA_APPRAISE_LOG 0x04 309 #define IMA_APPRAISE_MODULES 0x08 310 #define IMA_APPRAISE_FIRMWARE 0x10 311 #define IMA_APPRAISE_POLICY 0x20 312 #define IMA_APPRAISE_KEXEC 0x40 313 314 #ifdef CONFIG_IMA_APPRAISE 315 int ima_check_blacklist(struct integrity_iint_cache *iint, 316 const struct modsig *modsig, int pcr); 317 int ima_appraise_measurement(enum ima_hooks func, 318 struct integrity_iint_cache *iint, 319 struct file *file, const unsigned char *filename, 320 struct evm_ima_xattr_data *xattr_value, 321 int xattr_len, const struct modsig *modsig); 322 int ima_must_appraise(struct mnt_idmap *idmap, struct inode *inode, 323 int mask, enum ima_hooks func); 324 void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file); 325 enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint, 326 enum ima_hooks func); 327 enum hash_algo ima_get_hash_algo(const struct evm_ima_xattr_data *xattr_value, 328 int xattr_len); 329 int ima_read_xattr(struct dentry *dentry, 330 struct evm_ima_xattr_data **xattr_value, int xattr_len); 331 332 #else 333 static inline int ima_check_blacklist(struct integrity_iint_cache *iint, 334 const struct modsig *modsig, int pcr) 335 { 336 return 0; 337 } 338 339 static inline int ima_appraise_measurement(enum ima_hooks func, 340 struct integrity_iint_cache *iint, 341 struct file *file, 342 const unsigned char *filename, 343 struct evm_ima_xattr_data *xattr_value, 344 int xattr_len, 345 const struct modsig *modsig) 346 { 347 return INTEGRITY_UNKNOWN; 348 } 349 350 static inline int ima_must_appraise(struct mnt_idmap *idmap, 351 struct inode *inode, int mask, 352 enum ima_hooks func) 353 { 354 return 0; 355 } 356 357 static inline void ima_update_xattr(struct integrity_iint_cache *iint, 358 struct file *file) 359 { 360 } 361 362 static inline enum integrity_status ima_get_cache_status(struct integrity_iint_cache 363 *iint, 364 enum ima_hooks func) 365 { 366 return INTEGRITY_UNKNOWN; 367 } 368 369 static inline enum hash_algo 370 ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len) 371 { 372 return ima_hash_algo; 373 } 374 375 static inline int ima_read_xattr(struct dentry *dentry, 376 struct evm_ima_xattr_data **xattr_value, 377 int xattr_len) 378 { 379 return 0; 380 } 381 382 #endif /* CONFIG_IMA_APPRAISE */ 383 384 #ifdef CONFIG_IMA_APPRAISE_MODSIG 385 int ima_read_modsig(enum ima_hooks func, const void *buf, loff_t buf_len, 386 struct modsig **modsig); 387 void ima_collect_modsig(struct modsig *modsig, const void *buf, loff_t size); 388 int ima_get_modsig_digest(const struct modsig *modsig, enum hash_algo *algo, 389 const u8 **digest, u32 *digest_size); 390 int ima_get_raw_modsig(const struct modsig *modsig, const void **data, 391 u32 *data_len); 392 void ima_free_modsig(struct modsig *modsig); 393 #else 394 static inline int ima_read_modsig(enum ima_hooks func, const void *buf, 395 loff_t buf_len, struct modsig **modsig) 396 { 397 return -EOPNOTSUPP; 398 } 399 400 static inline void ima_collect_modsig(struct modsig *modsig, const void *buf, 401 loff_t size) 402 { 403 } 404 405 static inline int ima_get_modsig_digest(const struct modsig *modsig, 406 enum hash_algo *algo, const u8 **digest, 407 u32 *digest_size) 408 { 409 return -EOPNOTSUPP; 410 } 411 412 static inline int ima_get_raw_modsig(const struct modsig *modsig, 413 const void **data, u32 *data_len) 414 { 415 return -EOPNOTSUPP; 416 } 417 418 static inline void ima_free_modsig(struct modsig *modsig) 419 { 420 } 421 #endif /* CONFIG_IMA_APPRAISE_MODSIG */ 422 423 /* LSM based policy rules require audit */ 424 #ifdef CONFIG_IMA_LSM_RULES 425 426 #define ima_filter_rule_init security_audit_rule_init 427 #define ima_filter_rule_free security_audit_rule_free 428 #define ima_filter_rule_match security_audit_rule_match 429 430 #else 431 432 static inline int ima_filter_rule_init(u32 field, u32 op, char *rulestr, 433 void **lsmrule) 434 { 435 return -EINVAL; 436 } 437 438 static inline void ima_filter_rule_free(void *lsmrule) 439 { 440 } 441 442 static inline int ima_filter_rule_match(u32 secid, u32 field, u32 op, 443 void *lsmrule) 444 { 445 return -EINVAL; 446 } 447 #endif /* CONFIG_IMA_LSM_RULES */ 448 449 #ifdef CONFIG_IMA_READ_POLICY 450 #define POLICY_FILE_FLAGS (S_IWUSR | S_IRUSR) 451 #else 452 #define POLICY_FILE_FLAGS S_IWUSR 453 #endif /* CONFIG_IMA_READ_POLICY */ 454 455 #endif /* __LINUX_IMA_H */ 456