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_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 /* set during initialization */ 47 extern int ima_initialized; 48 extern int ima_used_chip; 49 extern int ima_hash_algo; 50 extern int ima_appraise; 51 52 /* IMA template field data definition */ 53 struct ima_field_data { 54 u8 *data; 55 u32 len; 56 }; 57 58 /* IMA template field definition */ 59 struct ima_template_field { 60 const char field_id[IMA_TEMPLATE_FIELD_ID_MAX_LEN]; 61 int (*field_init) (struct integrity_iint_cache *iint, struct file *file, 62 const unsigned char *filename, 63 struct evm_ima_xattr_data *xattr_value, 64 int xattr_len, struct ima_field_data *field_data); 65 void (*field_show) (struct seq_file *m, enum ima_show_type show, 66 struct ima_field_data *field_data); 67 }; 68 69 /* IMA template descriptor definition */ 70 struct ima_template_desc { 71 char *name; 72 char *fmt; 73 int num_fields; 74 struct ima_template_field **fields; 75 }; 76 77 struct ima_template_entry { 78 u8 digest[TPM_DIGEST_SIZE]; /* sha1 or md5 measurement hash */ 79 struct ima_template_desc *template_desc; /* template descriptor */ 80 u32 template_data_len; 81 struct ima_field_data template_data[0]; /* template related data */ 82 }; 83 84 struct ima_queue_entry { 85 struct hlist_node hnext; /* place in hash collision list */ 86 struct list_head later; /* place in ima_measurements list */ 87 struct ima_template_entry *entry; 88 }; 89 extern struct list_head ima_measurements; /* list of all measurements */ 90 91 /* Internal IMA function definitions */ 92 int ima_init(void); 93 void ima_cleanup(void); 94 int ima_fs_init(void); 95 void ima_fs_cleanup(void); 96 int ima_inode_alloc(struct inode *inode); 97 int ima_add_template_entry(struct ima_template_entry *entry, int violation, 98 const char *op, struct inode *inode, 99 const unsigned char *filename); 100 int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash); 101 int ima_calc_field_array_hash(struct ima_field_data *field_data, 102 struct ima_template_desc *desc, int num_fields, 103 struct ima_digest_data *hash); 104 int __init ima_calc_boot_aggregate(struct ima_digest_data *hash); 105 void ima_add_violation(struct file *file, const unsigned char *filename, 106 const char *op, const char *cause); 107 int ima_init_crypto(void); 108 void ima_putc(struct seq_file *m, void *data, int datalen); 109 void ima_print_digest(struct seq_file *m, u8 *digest, int size); 110 struct ima_template_desc *ima_template_desc_current(void); 111 int ima_init_template(void); 112 113 int ima_init_template(void); 114 115 /* 116 * used to protect h_table and sha_table 117 */ 118 extern spinlock_t ima_queue_lock; 119 120 struct ima_h_table { 121 atomic_long_t len; /* number of stored measurements in the list */ 122 atomic_long_t violations; 123 struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE]; 124 }; 125 extern struct ima_h_table ima_htable; 126 127 static inline unsigned long ima_hash_key(u8 *digest) 128 { 129 return hash_long(*digest, IMA_HASH_BITS); 130 } 131 132 /* LIM API function definitions */ 133 int ima_get_action(struct inode *inode, int mask, int function); 134 int ima_must_measure(struct inode *inode, int mask, int function); 135 int ima_collect_measurement(struct integrity_iint_cache *iint, 136 struct file *file, 137 struct evm_ima_xattr_data **xattr_value, 138 int *xattr_len); 139 void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file, 140 const unsigned char *filename, 141 struct evm_ima_xattr_data *xattr_value, 142 int xattr_len); 143 void ima_audit_measurement(struct integrity_iint_cache *iint, 144 const unsigned char *filename); 145 int ima_alloc_init_template(struct integrity_iint_cache *iint, 146 struct file *file, const unsigned char *filename, 147 struct evm_ima_xattr_data *xattr_value, 148 int xattr_len, struct ima_template_entry **entry); 149 int ima_store_template(struct ima_template_entry *entry, int violation, 150 struct inode *inode, const unsigned char *filename); 151 void ima_free_template_entry(struct ima_template_entry *entry); 152 const char *ima_d_path(struct path *path, char **pathbuf); 153 154 /* rbtree tree calls to lookup, insert, delete 155 * integrity data associated with an inode. 156 */ 157 struct integrity_iint_cache *integrity_iint_insert(struct inode *inode); 158 struct integrity_iint_cache *integrity_iint_find(struct inode *inode); 159 160 /* IMA policy related functions */ 161 enum ima_hooks { FILE_CHECK = 1, MMAP_CHECK, BPRM_CHECK, MODULE_CHECK, POST_SETATTR }; 162 163 int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask, 164 int flags); 165 void ima_init_policy(void); 166 void ima_update_policy(void); 167 ssize_t ima_parse_add_rule(char *); 168 void ima_delete_rules(void); 169 170 /* Appraise integrity measurements */ 171 #define IMA_APPRAISE_ENFORCE 0x01 172 #define IMA_APPRAISE_FIX 0x02 173 #define IMA_APPRAISE_MODULES 0x04 174 175 #ifdef CONFIG_IMA_APPRAISE 176 int ima_appraise_measurement(int func, struct integrity_iint_cache *iint, 177 struct file *file, const unsigned char *filename, 178 struct evm_ima_xattr_data *xattr_value, 179 int xattr_len); 180 int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func); 181 void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file); 182 enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint, 183 int func); 184 void ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len, 185 struct ima_digest_data *hash); 186 int ima_read_xattr(struct dentry *dentry, 187 struct evm_ima_xattr_data **xattr_value); 188 189 #else 190 static inline int ima_appraise_measurement(int func, 191 struct integrity_iint_cache *iint, 192 struct file *file, 193 const unsigned char *filename, 194 struct evm_ima_xattr_data *xattr_value, 195 int xattr_len) 196 { 197 return INTEGRITY_UNKNOWN; 198 } 199 200 static inline int ima_must_appraise(struct inode *inode, int mask, 201 enum ima_hooks func) 202 { 203 return 0; 204 } 205 206 static inline void ima_update_xattr(struct integrity_iint_cache *iint, 207 struct file *file) 208 { 209 } 210 211 static inline enum integrity_status ima_get_cache_status(struct integrity_iint_cache 212 *iint, int func) 213 { 214 return INTEGRITY_UNKNOWN; 215 } 216 217 static inline void ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, 218 int xattr_len, 219 struct ima_digest_data *hash) 220 { 221 } 222 223 static inline int ima_read_xattr(struct dentry *dentry, 224 struct evm_ima_xattr_data **xattr_value) 225 { 226 return 0; 227 } 228 229 #endif 230 231 /* LSM based policy rules require audit */ 232 #ifdef CONFIG_IMA_LSM_RULES 233 234 #define security_filter_rule_init security_audit_rule_init 235 #define security_filter_rule_match security_audit_rule_match 236 237 #else 238 239 static inline int security_filter_rule_init(u32 field, u32 op, char *rulestr, 240 void **lsmrule) 241 { 242 return -EINVAL; 243 } 244 245 static inline int security_filter_rule_match(u32 secid, u32 field, u32 op, 246 void *lsmrule, 247 struct audit_context *actx) 248 { 249 return -EINVAL; 250 } 251 #endif /* CONFIG_IMA_LSM_RULES */ 252 #endif 253