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