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 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_initialized; 53 extern int ima_used_chip; 54 extern int ima_hash_algo; 55 extern int ima_appraise; 56 57 /* IMA event related data */ 58 struct ima_event_data { 59 struct integrity_iint_cache *iint; 60 struct file *file; 61 const unsigned char *filename; 62 struct evm_ima_xattr_data *xattr_value; 63 int xattr_len; 64 const char *violation; 65 }; 66 67 /* IMA template field data definition */ 68 struct ima_field_data { 69 u8 *data; 70 u32 len; 71 }; 72 73 /* IMA template field definition */ 74 struct ima_template_field { 75 const char field_id[IMA_TEMPLATE_FIELD_ID_MAX_LEN]; 76 int (*field_init)(struct ima_event_data *event_data, 77 struct ima_field_data *field_data); 78 void (*field_show)(struct seq_file *m, enum ima_show_type show, 79 struct ima_field_data *field_data); 80 }; 81 82 /* IMA template descriptor definition */ 83 struct ima_template_desc { 84 char *name; 85 char *fmt; 86 int num_fields; 87 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 /* Internal IMA function definitions */ 106 int ima_init(void); 107 int ima_fs_init(void); 108 int ima_add_template_entry(struct ima_template_entry *entry, int violation, 109 const char *op, struct inode *inode, 110 const unsigned char *filename); 111 int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash); 112 int ima_calc_buffer_hash(const void *buf, loff_t len, 113 struct ima_digest_data *hash); 114 int ima_calc_field_array_hash(struct ima_field_data *field_data, 115 struct ima_template_desc *desc, int num_fields, 116 struct ima_digest_data *hash); 117 int __init ima_calc_boot_aggregate(struct ima_digest_data *hash); 118 void ima_add_violation(struct file *file, const unsigned char *filename, 119 struct integrity_iint_cache *iint, 120 const char *op, const char *cause); 121 int ima_init_crypto(void); 122 void ima_putc(struct seq_file *m, void *data, int datalen); 123 void ima_print_digest(struct seq_file *m, u8 *digest, u32 size); 124 struct ima_template_desc *ima_template_desc_current(void); 125 int ima_init_template(void); 126 127 /* 128 * used to protect h_table and sha_table 129 */ 130 extern spinlock_t ima_queue_lock; 131 132 struct ima_h_table { 133 atomic_long_t len; /* number of stored measurements in the list */ 134 atomic_long_t violations; 135 struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE]; 136 }; 137 extern struct ima_h_table ima_htable; 138 139 static inline unsigned long ima_hash_key(u8 *digest) 140 { 141 return hash_long(*digest, IMA_HASH_BITS); 142 } 143 144 enum ima_hooks { 145 FILE_CHECK = 1, 146 MMAP_CHECK, 147 BPRM_CHECK, 148 POST_SETATTR, 149 MODULE_CHECK, 150 FIRMWARE_CHECK, 151 KEXEC_KERNEL_CHECK, 152 KEXEC_INITRAMFS_CHECK, 153 POLICY_CHECK, 154 MAX_CHECK 155 }; 156 157 /* LIM API function definitions */ 158 int ima_get_action(struct inode *inode, int mask, 159 enum ima_hooks func, int *pcr); 160 int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func); 161 int ima_collect_measurement(struct integrity_iint_cache *iint, 162 struct file *file, void *buf, loff_t size, 163 enum hash_algo algo); 164 void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file, 165 const unsigned char *filename, 166 struct evm_ima_xattr_data *xattr_value, 167 int xattr_len, int pcr); 168 void ima_audit_measurement(struct integrity_iint_cache *iint, 169 const unsigned char *filename); 170 int ima_alloc_init_template(struct ima_event_data *event_data, 171 struct ima_template_entry **entry); 172 int ima_store_template(struct ima_template_entry *entry, int violation, 173 struct inode *inode, 174 const unsigned char *filename, int pcr); 175 void ima_free_template_entry(struct ima_template_entry *entry); 176 const char *ima_d_path(const struct path *path, char **pathbuf); 177 178 /* IMA policy related functions */ 179 int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask, 180 int flags, int *pcr); 181 void ima_init_policy(void); 182 void ima_update_policy(void); 183 void ima_update_policy_flag(void); 184 ssize_t ima_parse_add_rule(char *); 185 void ima_delete_rules(void); 186 int ima_check_policy(void); 187 void *ima_policy_start(struct seq_file *m, loff_t *pos); 188 void *ima_policy_next(struct seq_file *m, void *v, loff_t *pos); 189 void ima_policy_stop(struct seq_file *m, void *v); 190 int ima_policy_show(struct seq_file *m, void *v); 191 192 /* Appraise integrity measurements */ 193 #define IMA_APPRAISE_ENFORCE 0x01 194 #define IMA_APPRAISE_FIX 0x02 195 #define IMA_APPRAISE_LOG 0x04 196 #define IMA_APPRAISE_MODULES 0x08 197 #define IMA_APPRAISE_FIRMWARE 0x10 198 #define IMA_APPRAISE_POLICY 0x20 199 200 #ifdef CONFIG_IMA_APPRAISE 201 int ima_appraise_measurement(enum ima_hooks func, 202 struct integrity_iint_cache *iint, 203 struct file *file, const unsigned char *filename, 204 struct evm_ima_xattr_data *xattr_value, 205 int xattr_len, int opened); 206 int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func); 207 void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file); 208 enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint, 209 enum ima_hooks func); 210 enum hash_algo ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, 211 int xattr_len); 212 int ima_read_xattr(struct dentry *dentry, 213 struct evm_ima_xattr_data **xattr_value); 214 215 #else 216 static inline int ima_appraise_measurement(enum ima_hooks func, 217 struct integrity_iint_cache *iint, 218 struct file *file, 219 const unsigned char *filename, 220 struct evm_ima_xattr_data *xattr_value, 221 int xattr_len, int opened) 222 { 223 return INTEGRITY_UNKNOWN; 224 } 225 226 static inline int ima_must_appraise(struct inode *inode, int mask, 227 enum ima_hooks func) 228 { 229 return 0; 230 } 231 232 static inline void ima_update_xattr(struct integrity_iint_cache *iint, 233 struct file *file) 234 { 235 } 236 237 static inline enum integrity_status ima_get_cache_status(struct integrity_iint_cache 238 *iint, 239 enum ima_hooks func) 240 { 241 return INTEGRITY_UNKNOWN; 242 } 243 244 static inline enum hash_algo 245 ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len) 246 { 247 return ima_hash_algo; 248 } 249 250 static inline int ima_read_xattr(struct dentry *dentry, 251 struct evm_ima_xattr_data **xattr_value) 252 { 253 return 0; 254 } 255 256 #endif 257 258 /* LSM based policy rules require audit */ 259 #ifdef CONFIG_IMA_LSM_RULES 260 261 #define security_filter_rule_init security_audit_rule_init 262 #define security_filter_rule_match security_audit_rule_match 263 264 #else 265 266 static inline int security_filter_rule_init(u32 field, u32 op, char *rulestr, 267 void **lsmrule) 268 { 269 return -EINVAL; 270 } 271 272 static inline int security_filter_rule_match(u32 secid, u32 field, u32 op, 273 void *lsmrule, 274 struct audit_context *actx) 275 { 276 return -EINVAL; 277 } 278 #endif /* CONFIG_IMA_TRUSTED_KEYRING */ 279 280 #ifdef CONFIG_IMA_READ_POLICY 281 #define POLICY_FILE_FLAGS (S_IWUSR | S_IRUSR) 282 #else 283 #define POLICY_FILE_FLAGS S_IWUSR 284 #endif /* CONFIG_IMA_WRITE_POLICY */ 285 286 #endif /* __LINUX_IMA_H */ 287