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