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