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 char *violation; 64 const void *buf; 65 int buf_len; 66 }; 67 68 /* IMA template field data definition */ 69 struct ima_field_data { 70 u8 *data; 71 u32 len; 72 }; 73 74 /* IMA template field definition */ 75 struct ima_template_field { 76 const char field_id[IMA_TEMPLATE_FIELD_ID_MAX_LEN]; 77 int (*field_init)(struct ima_event_data *event_data, 78 struct ima_field_data *field_data); 79 void (*field_show)(struct seq_file *m, enum ima_show_type show, 80 struct ima_field_data *field_data); 81 }; 82 83 /* IMA template descriptor definition */ 84 struct ima_template_desc { 85 struct list_head list; 86 char *name; 87 char *fmt; 88 int num_fields; 89 const struct ima_template_field **fields; 90 }; 91 92 struct ima_template_entry { 93 int pcr; 94 u8 digest[TPM_DIGEST_SIZE]; /* sha1 or md5 measurement hash */ 95 struct ima_template_desc *template_desc; /* template descriptor */ 96 u32 template_data_len; 97 struct ima_field_data template_data[0]; /* template related data */ 98 }; 99 100 struct ima_queue_entry { 101 struct hlist_node hnext; /* place in hash collision list */ 102 struct list_head later; /* place in ima_measurements list */ 103 struct ima_template_entry *entry; 104 }; 105 extern struct list_head ima_measurements; /* list of all measurements */ 106 107 /* Some details preceding the binary serialized measurement list */ 108 struct ima_kexec_hdr { 109 u16 version; 110 u16 _reserved0; 111 u32 _reserved1; 112 u64 buffer_size; 113 u64 count; 114 }; 115 116 #ifdef CONFIG_HAVE_IMA_KEXEC 117 void ima_load_kexec_buffer(void); 118 #else 119 static inline void ima_load_kexec_buffer(void) {} 120 #endif /* CONFIG_HAVE_IMA_KEXEC */ 121 122 /* 123 * The default binary_runtime_measurements list format is defined as the 124 * platform native format. The canonical format is defined as little-endian. 125 */ 126 extern bool ima_canonical_fmt; 127 128 /* Internal IMA function definitions */ 129 int ima_init(void); 130 int ima_fs_init(void); 131 int ima_add_template_entry(struct ima_template_entry *entry, int violation, 132 const char *op, struct inode *inode, 133 const unsigned char *filename); 134 int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash); 135 int ima_calc_buffer_hash(const void *buf, loff_t len, 136 struct ima_digest_data *hash); 137 int ima_calc_field_array_hash(struct ima_field_data *field_data, 138 struct ima_template_desc *desc, int num_fields, 139 struct ima_digest_data *hash); 140 int __init ima_calc_boot_aggregate(struct ima_digest_data *hash); 141 void ima_add_violation(struct file *file, const unsigned char *filename, 142 struct integrity_iint_cache *iint, 143 const char *op, const char *cause); 144 int ima_init_crypto(void); 145 void ima_putc(struct seq_file *m, void *data, int datalen); 146 void ima_print_digest(struct seq_file *m, u8 *digest, u32 size); 147 int template_desc_init_fields(const char *template_fmt, 148 const struct ima_template_field ***fields, 149 int *num_fields); 150 struct ima_template_desc *ima_template_desc_current(void); 151 struct ima_template_desc *lookup_template_desc(const char *name); 152 int ima_restore_measurement_entry(struct ima_template_entry *entry); 153 int ima_restore_measurement_list(loff_t bufsize, void *buf); 154 int ima_measurements_show(struct seq_file *m, void *v); 155 unsigned long ima_get_binary_runtime_size(void); 156 int ima_init_template(void); 157 void ima_init_template_list(void); 158 int __init ima_init_digests(void); 159 int ima_lsm_policy_change(struct notifier_block *nb, unsigned long event, 160 void *lsm_data); 161 162 /* 163 * used to protect h_table and sha_table 164 */ 165 extern spinlock_t ima_queue_lock; 166 167 struct ima_h_table { 168 atomic_long_t len; /* number of stored measurements in the list */ 169 atomic_long_t violations; 170 struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE]; 171 }; 172 extern struct ima_h_table ima_htable; 173 174 static inline unsigned long ima_hash_key(u8 *digest) 175 { 176 return hash_long(*digest, IMA_HASH_BITS); 177 } 178 179 #define __ima_hooks(hook) \ 180 hook(NONE) \ 181 hook(FILE_CHECK) \ 182 hook(MMAP_CHECK) \ 183 hook(BPRM_CHECK) \ 184 hook(CREDS_CHECK) \ 185 hook(POST_SETATTR) \ 186 hook(MODULE_CHECK) \ 187 hook(FIRMWARE_CHECK) \ 188 hook(KEXEC_KERNEL_CHECK) \ 189 hook(KEXEC_INITRAMFS_CHECK) \ 190 hook(POLICY_CHECK) \ 191 hook(KEXEC_CMDLINE) \ 192 hook(MAX_CHECK) 193 #define __ima_hook_enumify(ENUM) ENUM, 194 195 enum ima_hooks { 196 __ima_hooks(__ima_hook_enumify) 197 }; 198 199 /* LIM API function definitions */ 200 int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid, 201 int mask, enum ima_hooks func, int *pcr, 202 struct ima_template_desc **template_desc); 203 int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func); 204 int ima_collect_measurement(struct integrity_iint_cache *iint, 205 struct file *file, void *buf, loff_t size, 206 enum hash_algo algo); 207 void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file, 208 const unsigned char *filename, 209 struct evm_ima_xattr_data *xattr_value, 210 int xattr_len, int pcr, 211 struct ima_template_desc *template_desc); 212 void ima_audit_measurement(struct integrity_iint_cache *iint, 213 const unsigned char *filename); 214 int ima_alloc_init_template(struct ima_event_data *event_data, 215 struct ima_template_entry **entry, 216 struct ima_template_desc *template_desc); 217 int ima_store_template(struct ima_template_entry *entry, int violation, 218 struct inode *inode, 219 const unsigned char *filename, int pcr); 220 void ima_free_template_entry(struct ima_template_entry *entry); 221 const char *ima_d_path(const struct path *path, char **pathbuf, char *filename); 222 223 /* IMA policy related functions */ 224 int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid, 225 enum ima_hooks func, int mask, int flags, int *pcr, 226 struct ima_template_desc **template_desc); 227 void ima_init_policy(void); 228 void ima_update_policy(void); 229 void ima_update_policy_flag(void); 230 ssize_t ima_parse_add_rule(char *); 231 void ima_delete_rules(void); 232 int ima_check_policy(void); 233 void *ima_policy_start(struct seq_file *m, loff_t *pos); 234 void *ima_policy_next(struct seq_file *m, void *v, loff_t *pos); 235 void ima_policy_stop(struct seq_file *m, void *v); 236 int ima_policy_show(struct seq_file *m, void *v); 237 238 /* Appraise integrity measurements */ 239 #define IMA_APPRAISE_ENFORCE 0x01 240 #define IMA_APPRAISE_FIX 0x02 241 #define IMA_APPRAISE_LOG 0x04 242 #define IMA_APPRAISE_MODULES 0x08 243 #define IMA_APPRAISE_FIRMWARE 0x10 244 #define IMA_APPRAISE_POLICY 0x20 245 #define IMA_APPRAISE_KEXEC 0x40 246 247 #ifdef CONFIG_IMA_APPRAISE 248 int ima_appraise_measurement(enum ima_hooks func, 249 struct integrity_iint_cache *iint, 250 struct file *file, const unsigned char *filename, 251 struct evm_ima_xattr_data *xattr_value, 252 int xattr_len); 253 int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func); 254 void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file); 255 enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint, 256 enum ima_hooks func); 257 enum hash_algo ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, 258 int xattr_len); 259 int ima_read_xattr(struct dentry *dentry, 260 struct evm_ima_xattr_data **xattr_value); 261 262 #else 263 static inline int ima_appraise_measurement(enum ima_hooks func, 264 struct integrity_iint_cache *iint, 265 struct file *file, 266 const unsigned char *filename, 267 struct evm_ima_xattr_data *xattr_value, 268 int xattr_len) 269 { 270 return INTEGRITY_UNKNOWN; 271 } 272 273 static inline int ima_must_appraise(struct inode *inode, int mask, 274 enum ima_hooks func) 275 { 276 return 0; 277 } 278 279 static inline void ima_update_xattr(struct integrity_iint_cache *iint, 280 struct file *file) 281 { 282 } 283 284 static inline enum integrity_status ima_get_cache_status(struct integrity_iint_cache 285 *iint, 286 enum ima_hooks func) 287 { 288 return INTEGRITY_UNKNOWN; 289 } 290 291 static inline enum hash_algo 292 ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len) 293 { 294 return ima_hash_algo; 295 } 296 297 static inline int ima_read_xattr(struct dentry *dentry, 298 struct evm_ima_xattr_data **xattr_value) 299 { 300 return 0; 301 } 302 303 #endif /* CONFIG_IMA_APPRAISE */ 304 305 /* LSM based policy rules require audit */ 306 #ifdef CONFIG_IMA_LSM_RULES 307 308 #define security_filter_rule_init security_audit_rule_init 309 #define security_filter_rule_match security_audit_rule_match 310 311 #else 312 313 static inline int security_filter_rule_init(u32 field, u32 op, char *rulestr, 314 void **lsmrule) 315 { 316 return -EINVAL; 317 } 318 319 static inline int security_filter_rule_match(u32 secid, u32 field, u32 op, 320 void *lsmrule) 321 { 322 return -EINVAL; 323 } 324 #endif /* CONFIG_IMA_LSM_RULES */ 325 326 #ifdef CONFIG_IMA_READ_POLICY 327 #define POLICY_FILE_FLAGS (S_IWUSR | S_IRUSR) 328 #else 329 #define POLICY_FILE_FLAGS S_IWUSR 330 #endif /* CONFIG_IMA_READ_POLICY */ 331 332 #endif /* __LINUX_IMA_H */ 333