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/security.h> 23 #include <linux/hash.h> 24 #include <linux/tpm.h> 25 #include <linux/audit.h> 26 27 #include "../integrity.h" 28 29 enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_BINARY_NO_FIELD_LEN, 30 IMA_SHOW_BINARY_OLD_STRING_FMT, IMA_SHOW_ASCII }; 31 enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8 }; 32 33 /* digest size for IMA, fits SHA1 or MD5 */ 34 #define IMA_DIGEST_SIZE SHA1_DIGEST_SIZE 35 #define IMA_EVENT_NAME_LEN_MAX 255 36 37 #define IMA_HASH_BITS 9 38 #define IMA_MEASURE_HTABLE_SIZE (1 << IMA_HASH_BITS) 39 40 #define IMA_TEMPLATE_FIELD_ID_MAX_LEN 16 41 #define IMA_TEMPLATE_NUM_FIELDS_MAX 15 42 43 #define IMA_TEMPLATE_IMA_NAME "ima" 44 #define IMA_TEMPLATE_IMA_FMT "d|n" 45 46 /* current content of the policy */ 47 extern int ima_policy_flag; 48 49 /* set during initialization */ 50 extern int ima_initialized; 51 extern int ima_used_chip; 52 extern int ima_hash_algo; 53 extern int ima_appraise; 54 55 /* IMA event related data */ 56 struct ima_event_data { 57 struct integrity_iint_cache *iint; 58 struct file *file; 59 const unsigned char *filename; 60 struct evm_ima_xattr_data *xattr_value; 61 int xattr_len; 62 const char *violation; 63 }; 64 65 /* IMA template field data definition */ 66 struct ima_field_data { 67 u8 *data; 68 u32 len; 69 }; 70 71 /* IMA template field definition */ 72 struct ima_template_field { 73 const char field_id[IMA_TEMPLATE_FIELD_ID_MAX_LEN]; 74 int (*field_init)(struct ima_event_data *event_data, 75 struct ima_field_data *field_data); 76 void (*field_show)(struct seq_file *m, enum ima_show_type show, 77 struct ima_field_data *field_data); 78 }; 79 80 /* IMA template descriptor definition */ 81 struct ima_template_desc { 82 char *name; 83 char *fmt; 84 int num_fields; 85 struct ima_template_field **fields; 86 }; 87 88 struct ima_template_entry { 89 u8 digest[TPM_DIGEST_SIZE]; /* sha1 or md5 measurement hash */ 90 struct ima_template_desc *template_desc; /* template descriptor */ 91 u32 template_data_len; 92 struct ima_field_data template_data[0]; /* template related data */ 93 }; 94 95 struct ima_queue_entry { 96 struct hlist_node hnext; /* place in hash collision list */ 97 struct list_head later; /* place in ima_measurements list */ 98 struct ima_template_entry *entry; 99 }; 100 extern struct list_head ima_measurements; /* list of all measurements */ 101 102 /* Internal IMA function definitions */ 103 int ima_init(void); 104 int ima_fs_init(void); 105 int ima_add_template_entry(struct ima_template_entry *entry, int violation, 106 const char *op, struct inode *inode, 107 const unsigned char *filename); 108 int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash); 109 int ima_calc_field_array_hash(struct ima_field_data *field_data, 110 struct ima_template_desc *desc, int num_fields, 111 struct ima_digest_data *hash); 112 int __init ima_calc_boot_aggregate(struct ima_digest_data *hash); 113 void ima_add_violation(struct file *file, const unsigned char *filename, 114 struct integrity_iint_cache *iint, 115 const char *op, const char *cause); 116 int ima_init_crypto(void); 117 void ima_putc(struct seq_file *m, void *data, int datalen); 118 void ima_print_digest(struct seq_file *m, u8 *digest, u32 size); 119 struct ima_template_desc *ima_template_desc_current(void); 120 int ima_init_template(void); 121 122 /* 123 * used to protect h_table and sha_table 124 */ 125 extern spinlock_t ima_queue_lock; 126 127 struct ima_h_table { 128 atomic_long_t len; /* number of stored measurements in the list */ 129 atomic_long_t violations; 130 struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE]; 131 }; 132 extern struct ima_h_table ima_htable; 133 134 static inline unsigned long ima_hash_key(u8 *digest) 135 { 136 return hash_long(*digest, IMA_HASH_BITS); 137 } 138 139 /* LIM API function definitions */ 140 int ima_get_action(struct inode *inode, int mask, int function); 141 int ima_must_measure(struct inode *inode, int mask, int function); 142 int ima_collect_measurement(struct integrity_iint_cache *iint, 143 struct file *file, 144 struct evm_ima_xattr_data **xattr_value, 145 int *xattr_len); 146 void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file, 147 const unsigned char *filename, 148 struct evm_ima_xattr_data *xattr_value, 149 int xattr_len); 150 void ima_audit_measurement(struct integrity_iint_cache *iint, 151 const unsigned char *filename); 152 int ima_alloc_init_template(struct ima_event_data *event_data, 153 struct ima_template_entry **entry); 154 int ima_store_template(struct ima_template_entry *entry, int violation, 155 struct inode *inode, const unsigned char *filename); 156 void ima_free_template_entry(struct ima_template_entry *entry); 157 const char *ima_d_path(struct path *path, char **pathbuf); 158 159 /* IMA policy related functions */ 160 enum ima_hooks { FILE_CHECK = 1, MMAP_CHECK, BPRM_CHECK, MODULE_CHECK, FIRMWARE_CHECK, POST_SETATTR }; 161 162 int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask, 163 int flags); 164 void ima_init_policy(void); 165 void ima_update_policy(void); 166 void ima_update_policy_flag(void); 167 ssize_t ima_parse_add_rule(char *); 168 void ima_delete_rules(void); 169 int ima_check_policy(void); 170 void *ima_policy_start(struct seq_file *m, loff_t *pos); 171 void *ima_policy_next(struct seq_file *m, void *v, loff_t *pos); 172 void ima_policy_stop(struct seq_file *m, void *v); 173 int ima_policy_show(struct seq_file *m, void *v); 174 175 /* Appraise integrity measurements */ 176 #define IMA_APPRAISE_ENFORCE 0x01 177 #define IMA_APPRAISE_FIX 0x02 178 #define IMA_APPRAISE_LOG 0x04 179 #define IMA_APPRAISE_MODULES 0x08 180 #define IMA_APPRAISE_FIRMWARE 0x10 181 182 #ifdef CONFIG_IMA_APPRAISE 183 int ima_appraise_measurement(int func, struct integrity_iint_cache *iint, 184 struct file *file, const unsigned char *filename, 185 struct evm_ima_xattr_data *xattr_value, 186 int xattr_len, int opened); 187 int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func); 188 void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file); 189 enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint, 190 int func); 191 void ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len, 192 struct ima_digest_data *hash); 193 int ima_read_xattr(struct dentry *dentry, 194 struct evm_ima_xattr_data **xattr_value); 195 196 #else 197 static inline int ima_appraise_measurement(int func, 198 struct integrity_iint_cache *iint, 199 struct file *file, 200 const unsigned char *filename, 201 struct evm_ima_xattr_data *xattr_value, 202 int xattr_len, int opened) 203 { 204 return INTEGRITY_UNKNOWN; 205 } 206 207 static inline int ima_must_appraise(struct inode *inode, int mask, 208 enum ima_hooks func) 209 { 210 return 0; 211 } 212 213 static inline void ima_update_xattr(struct integrity_iint_cache *iint, 214 struct file *file) 215 { 216 } 217 218 static inline enum integrity_status ima_get_cache_status(struct integrity_iint_cache 219 *iint, int func) 220 { 221 return INTEGRITY_UNKNOWN; 222 } 223 224 static inline void ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, 225 int xattr_len, 226 struct ima_digest_data *hash) 227 { 228 } 229 230 static inline int ima_read_xattr(struct dentry *dentry, 231 struct evm_ima_xattr_data **xattr_value) 232 { 233 return 0; 234 } 235 236 #endif 237 238 /* LSM based policy rules require audit */ 239 #ifdef CONFIG_IMA_LSM_RULES 240 241 #define security_filter_rule_init security_audit_rule_init 242 #define security_filter_rule_match security_audit_rule_match 243 244 #else 245 246 static inline int security_filter_rule_init(u32 field, u32 op, char *rulestr, 247 void **lsmrule) 248 { 249 return -EINVAL; 250 } 251 252 static inline int security_filter_rule_match(u32 secid, u32 field, u32 op, 253 void *lsmrule, 254 struct audit_context *actx) 255 { 256 return -EINVAL; 257 } 258 #endif /* CONFIG_IMA_TRUSTED_KEYRING */ 259 260 #ifdef CONFIG_IMA_READ_POLICY 261 #define POLICY_FILE_FLAGS (S_IWUSR | S_IRUSR) 262 #else 263 #define POLICY_FILE_FLAGS S_IWUSR 264 #endif /* CONFIG_IMA_WRITE_POLICY */ 265 266 #endif /* __LINUX_IMA_H */ 267