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(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(CRITICAL_DATA, critical_data) \ 204 hook(SETXATTR_CHECK, setxattr_check) \ 205 hook(MAX_CHECK, none) 206 207 #define __ima_hook_enumify(ENUM, str) ENUM, 208 #define __ima_stringify(arg) (#arg) 209 #define __ima_hook_measuring_stringify(ENUM, str) \ 210 (__ima_stringify(measuring_ ##str)), 211 212 enum ima_hooks { 213 __ima_hooks(__ima_hook_enumify) 214 }; 215 216 static const char * const ima_hooks_measure_str[] = { 217 __ima_hooks(__ima_hook_measuring_stringify) 218 }; 219 220 static inline const char *func_measure_str(enum ima_hooks func) 221 { 222 if (func >= MAX_CHECK) 223 return ima_hooks_measure_str[NONE]; 224 225 return ima_hooks_measure_str[func]; 226 } 227 228 extern const char *const func_tokens[]; 229 230 struct modsig; 231 232 #ifdef CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS 233 /* 234 * To track keys that need to be measured. 235 */ 236 struct ima_key_entry { 237 struct list_head list; 238 void *payload; 239 size_t payload_len; 240 char *keyring_name; 241 }; 242 void ima_init_key_queue(void); 243 bool ima_should_queue_key(void); 244 bool ima_queue_key(struct key *keyring, const void *payload, 245 size_t payload_len); 246 void ima_process_queued_keys(void); 247 #else 248 static inline void ima_init_key_queue(void) {} 249 static inline bool ima_should_queue_key(void) { return false; } 250 static inline bool ima_queue_key(struct key *keyring, 251 const void *payload, 252 size_t payload_len) { return false; } 253 static inline void ima_process_queued_keys(void) {} 254 #endif /* CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS */ 255 256 /* LIM API function definitions */ 257 int ima_get_action(struct user_namespace *mnt_userns, struct inode *inode, 258 const struct cred *cred, u32 secid, int mask, 259 enum ima_hooks func, int *pcr, 260 struct ima_template_desc **template_desc, 261 const char *func_data, unsigned int *allowed_algos); 262 int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func); 263 int ima_collect_measurement(struct integrity_iint_cache *iint, 264 struct file *file, void *buf, loff_t size, 265 enum hash_algo algo, struct modsig *modsig); 266 void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file, 267 const unsigned char *filename, 268 struct evm_ima_xattr_data *xattr_value, 269 int xattr_len, const struct modsig *modsig, int pcr, 270 struct ima_template_desc *template_desc); 271 int process_buffer_measurement(struct user_namespace *mnt_userns, 272 struct inode *inode, const void *buf, int size, 273 const char *eventname, enum ima_hooks func, 274 int pcr, const char *func_data, 275 bool buf_hash, u8 *digest, size_t digest_len); 276 void ima_audit_measurement(struct integrity_iint_cache *iint, 277 const unsigned char *filename); 278 int ima_alloc_init_template(struct ima_event_data *event_data, 279 struct ima_template_entry **entry, 280 struct ima_template_desc *template_desc); 281 int ima_store_template(struct ima_template_entry *entry, int violation, 282 struct inode *inode, 283 const unsigned char *filename, int pcr); 284 void ima_free_template_entry(struct ima_template_entry *entry); 285 const char *ima_d_path(const struct path *path, char **pathbuf, char *filename); 286 287 /* IMA policy related functions */ 288 int ima_match_policy(struct user_namespace *mnt_userns, struct inode *inode, 289 const struct cred *cred, u32 secid, enum ima_hooks func, 290 int mask, int flags, int *pcr, 291 struct ima_template_desc **template_desc, 292 const char *func_data, unsigned int *allowed_algos); 293 void ima_init_policy(void); 294 void ima_update_policy(void); 295 void ima_update_policy_flags(void); 296 ssize_t ima_parse_add_rule(char *); 297 void ima_delete_rules(void); 298 int ima_check_policy(void); 299 void *ima_policy_start(struct seq_file *m, loff_t *pos); 300 void *ima_policy_next(struct seq_file *m, void *v, loff_t *pos); 301 void ima_policy_stop(struct seq_file *m, void *v); 302 int ima_policy_show(struct seq_file *m, void *v); 303 304 /* Appraise integrity measurements */ 305 #define IMA_APPRAISE_ENFORCE 0x01 306 #define IMA_APPRAISE_FIX 0x02 307 #define IMA_APPRAISE_LOG 0x04 308 #define IMA_APPRAISE_MODULES 0x08 309 #define IMA_APPRAISE_FIRMWARE 0x10 310 #define IMA_APPRAISE_POLICY 0x20 311 #define IMA_APPRAISE_KEXEC 0x40 312 313 #ifdef CONFIG_IMA_APPRAISE 314 int ima_check_blacklist(struct integrity_iint_cache *iint, 315 const struct modsig *modsig, int pcr); 316 int ima_appraise_measurement(enum ima_hooks func, 317 struct integrity_iint_cache *iint, 318 struct file *file, const unsigned char *filename, 319 struct evm_ima_xattr_data *xattr_value, 320 int xattr_len, const struct modsig *modsig); 321 int ima_must_appraise(struct user_namespace *mnt_userns, struct inode *inode, 322 int mask, enum ima_hooks func); 323 void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file); 324 enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint, 325 enum ima_hooks func); 326 enum hash_algo ima_get_hash_algo(const struct evm_ima_xattr_data *xattr_value, 327 int xattr_len); 328 int ima_read_xattr(struct dentry *dentry, 329 struct evm_ima_xattr_data **xattr_value); 330 331 #else 332 static inline int ima_check_blacklist(struct integrity_iint_cache *iint, 333 const struct modsig *modsig, int pcr) 334 { 335 return 0; 336 } 337 338 static inline int ima_appraise_measurement(enum ima_hooks func, 339 struct integrity_iint_cache *iint, 340 struct file *file, 341 const unsigned char *filename, 342 struct evm_ima_xattr_data *xattr_value, 343 int xattr_len, 344 const struct modsig *modsig) 345 { 346 return INTEGRITY_UNKNOWN; 347 } 348 349 static inline int ima_must_appraise(struct user_namespace *mnt_userns, 350 struct inode *inode, int mask, 351 enum ima_hooks func) 352 { 353 return 0; 354 } 355 356 static inline void ima_update_xattr(struct integrity_iint_cache *iint, 357 struct file *file) 358 { 359 } 360 361 static inline enum integrity_status ima_get_cache_status(struct integrity_iint_cache 362 *iint, 363 enum ima_hooks func) 364 { 365 return INTEGRITY_UNKNOWN; 366 } 367 368 static inline enum hash_algo 369 ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len) 370 { 371 return ima_hash_algo; 372 } 373 374 static inline int ima_read_xattr(struct dentry *dentry, 375 struct evm_ima_xattr_data **xattr_value) 376 { 377 return 0; 378 } 379 380 #endif /* CONFIG_IMA_APPRAISE */ 381 382 #ifdef CONFIG_IMA_APPRAISE_MODSIG 383 int ima_read_modsig(enum ima_hooks func, const void *buf, loff_t buf_len, 384 struct modsig **modsig); 385 void ima_collect_modsig(struct modsig *modsig, const void *buf, loff_t size); 386 int ima_get_modsig_digest(const struct modsig *modsig, enum hash_algo *algo, 387 const u8 **digest, u32 *digest_size); 388 int ima_get_raw_modsig(const struct modsig *modsig, const void **data, 389 u32 *data_len); 390 void ima_free_modsig(struct modsig *modsig); 391 #else 392 static inline int ima_read_modsig(enum ima_hooks func, const void *buf, 393 loff_t buf_len, struct modsig **modsig) 394 { 395 return -EOPNOTSUPP; 396 } 397 398 static inline void ima_collect_modsig(struct modsig *modsig, const void *buf, 399 loff_t size) 400 { 401 } 402 403 static inline int ima_get_modsig_digest(const struct modsig *modsig, 404 enum hash_algo *algo, const u8 **digest, 405 u32 *digest_size) 406 { 407 return -EOPNOTSUPP; 408 } 409 410 static inline int ima_get_raw_modsig(const struct modsig *modsig, 411 const void **data, u32 *data_len) 412 { 413 return -EOPNOTSUPP; 414 } 415 416 static inline void ima_free_modsig(struct modsig *modsig) 417 { 418 } 419 #endif /* CONFIG_IMA_APPRAISE_MODSIG */ 420 421 /* LSM based policy rules require audit */ 422 #ifdef CONFIG_IMA_LSM_RULES 423 424 #define ima_filter_rule_init security_audit_rule_init 425 #define ima_filter_rule_free security_audit_rule_free 426 #define ima_filter_rule_match security_audit_rule_match 427 428 #else 429 430 static inline int ima_filter_rule_init(u32 field, u32 op, char *rulestr, 431 void **lsmrule) 432 { 433 return -EINVAL; 434 } 435 436 static inline void ima_filter_rule_free(void *lsmrule) 437 { 438 } 439 440 static inline int ima_filter_rule_match(u32 secid, u32 field, u32 op, 441 void *lsmrule) 442 { 443 return -EINVAL; 444 } 445 #endif /* CONFIG_IMA_LSM_RULES */ 446 447 #ifdef CONFIG_IMA_READ_POLICY 448 #define POLICY_FILE_FLAGS (S_IWUSR | S_IRUSR) 449 #else 450 #define POLICY_FILE_FLAGS S_IWUSR 451 #endif /* CONFIG_IMA_READ_POLICY */ 452 453 #endif /* __LINUX_IMA_H */ 454