1 /* 2 * Copyright (C) 2005,2006,2007,2008 IBM Corporation 3 * 4 * Authors: 5 * Reiner Sailer <sailer@watson.ibm.com> 6 * Mimi Zohar <zohar@us.ibm.com> 7 * 8 * This program is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public License as 10 * published by the Free Software Foundation, version 2 of the 11 * License. 12 * 13 * File: ima.h 14 * internal Integrity Measurement Architecture (IMA) definitions 15 */ 16 17 #ifndef __LINUX_IMA_H 18 #define __LINUX_IMA_H 19 20 #include <linux/types.h> 21 #include <linux/crypto.h> 22 #include <linux/fs.h> 23 #include <linux/security.h> 24 #include <linux/hash.h> 25 #include <linux/tpm.h> 26 #include <linux/audit.h> 27 #include <crypto/hash_info.h> 28 29 #include "../integrity.h" 30 31 #ifdef CONFIG_HAVE_IMA_KEXEC 32 #include <asm/ima.h> 33 #endif 34 35 enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_BINARY_NO_FIELD_LEN, 36 IMA_SHOW_BINARY_OLD_STRING_FMT, IMA_SHOW_ASCII }; 37 enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8 }; 38 39 /* digest size for IMA, fits SHA1 or MD5 */ 40 #define IMA_DIGEST_SIZE SHA1_DIGEST_SIZE 41 #define IMA_EVENT_NAME_LEN_MAX 255 42 43 #define IMA_HASH_BITS 9 44 #define IMA_MEASURE_HTABLE_SIZE (1 << IMA_HASH_BITS) 45 46 #define IMA_TEMPLATE_FIELD_ID_MAX_LEN 16 47 #define IMA_TEMPLATE_NUM_FIELDS_MAX 15 48 49 #define IMA_TEMPLATE_IMA_NAME "ima" 50 #define IMA_TEMPLATE_IMA_FMT "d|n" 51 52 /* current content of the policy */ 53 extern int ima_policy_flag; 54 55 /* set during initialization */ 56 extern int ima_hash_algo; 57 extern int ima_appraise; 58 extern struct tpm_chip *ima_tpm_chip; 59 60 /* IMA event related data */ 61 struct ima_event_data { 62 struct integrity_iint_cache *iint; 63 struct file *file; 64 const unsigned char *filename; 65 struct evm_ima_xattr_data *xattr_value; 66 int xattr_len; 67 const char *violation; 68 }; 69 70 /* IMA template field data definition */ 71 struct ima_field_data { 72 u8 *data; 73 u32 len; 74 }; 75 76 /* IMA template field definition */ 77 struct ima_template_field { 78 const char field_id[IMA_TEMPLATE_FIELD_ID_MAX_LEN]; 79 int (*field_init)(struct ima_event_data *event_data, 80 struct ima_field_data *field_data); 81 void (*field_show)(struct seq_file *m, enum ima_show_type show, 82 struct ima_field_data *field_data); 83 }; 84 85 /* IMA template descriptor definition */ 86 struct ima_template_desc { 87 struct list_head list; 88 char *name; 89 char *fmt; 90 int num_fields; 91 struct ima_template_field **fields; 92 }; 93 94 struct ima_template_entry { 95 int pcr; 96 u8 digest[TPM_DIGEST_SIZE]; /* sha1 or md5 measurement hash */ 97 struct ima_template_desc *template_desc; /* template descriptor */ 98 u32 template_data_len; 99 struct ima_field_data template_data[0]; /* template related data */ 100 }; 101 102 struct ima_queue_entry { 103 struct hlist_node hnext; /* place in hash collision list */ 104 struct list_head later; /* place in ima_measurements list */ 105 struct ima_template_entry *entry; 106 }; 107 extern struct list_head ima_measurements; /* list of all measurements */ 108 109 /* Some details preceding the binary serialized measurement list */ 110 struct ima_kexec_hdr { 111 u16 version; 112 u16 _reserved0; 113 u32 _reserved1; 114 u64 buffer_size; 115 u64 count; 116 }; 117 118 #ifdef CONFIG_HAVE_IMA_KEXEC 119 void ima_load_kexec_buffer(void); 120 #else 121 static inline void ima_load_kexec_buffer(void) {} 122 #endif /* CONFIG_HAVE_IMA_KEXEC */ 123 124 /* 125 * The default binary_runtime_measurements list format is defined as the 126 * platform native format. The canonical format is defined as little-endian. 127 */ 128 extern bool ima_canonical_fmt; 129 130 /* Internal IMA function definitions */ 131 int ima_init(void); 132 int ima_fs_init(void); 133 int ima_add_template_entry(struct ima_template_entry *entry, int violation, 134 const char *op, struct inode *inode, 135 const unsigned char *filename); 136 int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash); 137 int ima_calc_buffer_hash(const void *buf, loff_t len, 138 struct ima_digest_data *hash); 139 int ima_calc_field_array_hash(struct ima_field_data *field_data, 140 struct ima_template_desc *desc, int num_fields, 141 struct ima_digest_data *hash); 142 int __init ima_calc_boot_aggregate(struct ima_digest_data *hash); 143 void ima_add_violation(struct file *file, const unsigned char *filename, 144 struct integrity_iint_cache *iint, 145 const char *op, const char *cause); 146 int ima_init_crypto(void); 147 void ima_putc(struct seq_file *m, void *data, int datalen); 148 void ima_print_digest(struct seq_file *m, u8 *digest, u32 size); 149 struct ima_template_desc *ima_template_desc_current(void); 150 int ima_restore_measurement_entry(struct ima_template_entry *entry); 151 int ima_restore_measurement_list(loff_t bufsize, void *buf); 152 int ima_measurements_show(struct seq_file *m, void *v); 153 unsigned long ima_get_binary_runtime_size(void); 154 int ima_init_template(void); 155 void ima_init_template_list(void); 156 157 /* 158 * used to protect h_table and sha_table 159 */ 160 extern spinlock_t ima_queue_lock; 161 162 struct ima_h_table { 163 atomic_long_t len; /* number of stored measurements in the list */ 164 atomic_long_t violations; 165 struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE]; 166 }; 167 extern struct ima_h_table ima_htable; 168 169 static inline unsigned long ima_hash_key(u8 *digest) 170 { 171 return hash_long(*digest, IMA_HASH_BITS); 172 } 173 174 #define __ima_hooks(hook) \ 175 hook(NONE) \ 176 hook(FILE_CHECK) \ 177 hook(MMAP_CHECK) \ 178 hook(BPRM_CHECK) \ 179 hook(CREDS_CHECK) \ 180 hook(POST_SETATTR) \ 181 hook(MODULE_CHECK) \ 182 hook(FIRMWARE_CHECK) \ 183 hook(KEXEC_KERNEL_CHECK) \ 184 hook(KEXEC_INITRAMFS_CHECK) \ 185 hook(POLICY_CHECK) \ 186 hook(MAX_CHECK) 187 #define __ima_hook_enumify(ENUM) ENUM, 188 189 enum ima_hooks { 190 __ima_hooks(__ima_hook_enumify) 191 }; 192 193 /* LIM API function definitions */ 194 int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid, 195 int mask, enum ima_hooks func, int *pcr); 196 int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func); 197 int ima_collect_measurement(struct integrity_iint_cache *iint, 198 struct file *file, void *buf, loff_t size, 199 enum hash_algo algo); 200 void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file, 201 const unsigned char *filename, 202 struct evm_ima_xattr_data *xattr_value, 203 int xattr_len, int pcr); 204 void ima_audit_measurement(struct integrity_iint_cache *iint, 205 const unsigned char *filename); 206 int ima_alloc_init_template(struct ima_event_data *event_data, 207 struct ima_template_entry **entry); 208 int ima_store_template(struct ima_template_entry *entry, int violation, 209 struct inode *inode, 210 const unsigned char *filename, int pcr); 211 void ima_free_template_entry(struct ima_template_entry *entry); 212 const char *ima_d_path(const struct path *path, char **pathbuf, char *filename); 213 214 /* IMA policy related functions */ 215 int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid, 216 enum ima_hooks func, int mask, int flags, int *pcr); 217 void ima_init_policy(void); 218 void ima_update_policy(void); 219 void ima_update_policy_flag(void); 220 ssize_t ima_parse_add_rule(char *); 221 void ima_delete_rules(void); 222 int ima_check_policy(void); 223 void *ima_policy_start(struct seq_file *m, loff_t *pos); 224 void *ima_policy_next(struct seq_file *m, void *v, loff_t *pos); 225 void ima_policy_stop(struct seq_file *m, void *v); 226 int ima_policy_show(struct seq_file *m, void *v); 227 228 /* Appraise integrity measurements */ 229 #define IMA_APPRAISE_ENFORCE 0x01 230 #define IMA_APPRAISE_FIX 0x02 231 #define IMA_APPRAISE_LOG 0x04 232 #define IMA_APPRAISE_MODULES 0x08 233 #define IMA_APPRAISE_FIRMWARE 0x10 234 #define IMA_APPRAISE_POLICY 0x20 235 #define IMA_APPRAISE_KEXEC 0x40 236 237 #ifdef CONFIG_IMA_APPRAISE 238 int ima_appraise_measurement(enum ima_hooks func, 239 struct integrity_iint_cache *iint, 240 struct file *file, const unsigned char *filename, 241 struct evm_ima_xattr_data *xattr_value, 242 int xattr_len); 243 int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func); 244 void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file); 245 enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint, 246 enum ima_hooks func); 247 enum hash_algo ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, 248 int xattr_len); 249 int ima_read_xattr(struct dentry *dentry, 250 struct evm_ima_xattr_data **xattr_value); 251 252 #else 253 static inline int ima_appraise_measurement(enum ima_hooks func, 254 struct integrity_iint_cache *iint, 255 struct file *file, 256 const unsigned char *filename, 257 struct evm_ima_xattr_data *xattr_value, 258 int xattr_len) 259 { 260 return INTEGRITY_UNKNOWN; 261 } 262 263 static inline int ima_must_appraise(struct inode *inode, int mask, 264 enum ima_hooks func) 265 { 266 return 0; 267 } 268 269 static inline void ima_update_xattr(struct integrity_iint_cache *iint, 270 struct file *file) 271 { 272 } 273 274 static inline enum integrity_status ima_get_cache_status(struct integrity_iint_cache 275 *iint, 276 enum ima_hooks func) 277 { 278 return INTEGRITY_UNKNOWN; 279 } 280 281 static inline enum hash_algo 282 ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len) 283 { 284 return ima_hash_algo; 285 } 286 287 static inline int ima_read_xattr(struct dentry *dentry, 288 struct evm_ima_xattr_data **xattr_value) 289 { 290 return 0; 291 } 292 293 #endif /* CONFIG_IMA_APPRAISE */ 294 295 /* LSM based policy rules require audit */ 296 #ifdef CONFIG_IMA_LSM_RULES 297 298 #define security_filter_rule_init security_audit_rule_init 299 #define security_filter_rule_match security_audit_rule_match 300 301 #else 302 303 static inline int security_filter_rule_init(u32 field, u32 op, char *rulestr, 304 void **lsmrule) 305 { 306 return -EINVAL; 307 } 308 309 static inline int security_filter_rule_match(u32 secid, u32 field, u32 op, 310 void *lsmrule, 311 struct audit_context *actx) 312 { 313 return -EINVAL; 314 } 315 #endif /* CONFIG_IMA_LSM_RULES */ 316 317 #ifdef CONFIG_IMA_READ_POLICY 318 #define POLICY_FILE_FLAGS (S_IWUSR | S_IRUSR) 319 #else 320 #define POLICY_FILE_FLAGS S_IWUSR 321 #endif /* CONFIG_IMA_READ_POLICY */ 322 323 #endif /* __LINUX_IMA_H */ 324