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/*
* Copyright (C) 2005,2006,2007,2008 IBM Corporation
*
* Authors:
* Reiner Sailer <sailer@watson.ibm.com>
* Mimi Zohar <zohar@us.ibm.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation, version 2 of the
* License.
*
* File: ima.h
* internal Integrity Measurement Architecture (IMA) definitions
*/
#ifndef __LINUX_IMA_H
#define __LINUX_IMA_H
#include <linux/types.h>
#include <linux/crypto.h>
#include <linux/security.h>
#include <linux/hash.h>
#include <linux/tpm.h>
#include <linux/audit.h>
#include "../integrity.h"
enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_BINARY_NO_FIELD_LEN,
IMA_SHOW_BINARY_OLD_STRING_FMT, IMA_SHOW_ASCII };
enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8 };
/* digest size for IMA, fits SHA1 or MD5 */
#define IMA_DIGEST_SIZE SHA1_DIGEST_SIZE
#define IMA_EVENT_NAME_LEN_MAX 255
#define IMA_HASH_BITS 9
#define IMA_MEASURE_HTABLE_SIZE (1 << IMA_HASH_BITS)
#define IMA_TEMPLATE_FIELD_ID_MAX_LEN 16
#define IMA_TEMPLATE_NUM_FIELDS_MAX 15
#define IMA_TEMPLATE_IMA_NAME "ima"
#define IMA_TEMPLATE_IMA_FMT "d|n"
/* current content of the policy */
extern int ima_policy_flag;
/* set during initialization */
extern int ima_initialized;
extern int ima_used_chip;
extern int ima_hash_algo;
extern int ima_appraise;
/* IMA event related data */
struct ima_event_data {
struct integrity_iint_cache *iint;
struct file *file;
const unsigned char *filename;
struct evm_ima_xattr_data *xattr_value;
int xattr_len;
const char *violation;
};
/* IMA template field data definition */
struct ima_field_data {
u8 *data;
u32 len;
};
/* IMA template field definition */
struct ima_template_field {
const char field_id[IMA_TEMPLATE_FIELD_ID_MAX_LEN];
int (*field_init)(struct ima_event_data *event_data,
struct ima_field_data *field_data);
void (*field_show)(struct seq_file *m, enum ima_show_type show,
struct ima_field_data *field_data);
};
/* IMA template descriptor definition */
struct ima_template_desc {
char *name;
char *fmt;
int num_fields;
struct ima_template_field **fields;
};
struct ima_template_entry {
u8 digest[TPM_DIGEST_SIZE]; /* sha1 or md5 measurement hash */
struct ima_template_desc *template_desc; /* template descriptor */
u32 template_data_len;
struct ima_field_data template_data[0]; /* template related data */
};
struct ima_queue_entry {
struct hlist_node hnext; /* place in hash collision list */
struct list_head later; /* place in ima_measurements list */
struct ima_template_entry *entry;
};
extern struct list_head ima_measurements; /* list of all measurements */
/* Internal IMA function definitions */
int ima_init(void);
int ima_fs_init(void);
int ima_add_template_entry(struct ima_template_entry *entry, int violation,
const char *op, struct inode *inode,
const unsigned char *filename);
int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash);
int ima_calc_field_array_hash(struct ima_field_data *field_data,
struct ima_template_desc *desc, int num_fields,
struct ima_digest_data *hash);
int __init ima_calc_boot_aggregate(struct ima_digest_data *hash);
void ima_add_violation(struct file *file, const unsigned char *filename,
struct integrity_iint_cache *iint,
const char *op, const char *cause);
int ima_init_crypto(void);
void ima_putc(struct seq_file *m, void *data, int datalen);
void ima_print_digest(struct seq_file *m, u8 *digest, u32 size);
struct ima_template_desc *ima_template_desc_current(void);
int ima_init_template(void);
/*
* used to protect h_table and sha_table
*/
extern spinlock_t ima_queue_lock;
struct ima_h_table {
atomic_long_t len; /* number of stored measurements in the list */
atomic_long_t violations;
struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE];
};
extern struct ima_h_table ima_htable;
static inline unsigned long ima_hash_key(u8 *digest)
{
return hash_long(*digest, IMA_HASH_BITS);
}
/* LIM API function definitions */
int ima_get_action(struct inode *inode, int mask, int function);
int ima_must_measure(struct inode *inode, int mask, int function);
int ima_collect_measurement(struct integrity_iint_cache *iint,
struct file *file,
struct evm_ima_xattr_data **xattr_value,
int *xattr_len);
void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file,
const unsigned char *filename,
struct evm_ima_xattr_data *xattr_value,
int xattr_len);
void ima_audit_measurement(struct integrity_iint_cache *iint,
const unsigned char *filename);
int ima_alloc_init_template(struct ima_event_data *event_data,
struct ima_template_entry **entry);
int ima_store_template(struct ima_template_entry *entry, int violation,
struct inode *inode, const unsigned char *filename);
void ima_free_template_entry(struct ima_template_entry *entry);
const char *ima_d_path(struct path *path, char **pathbuf);
/* IMA policy related functions */
enum ima_hooks { FILE_CHECK = 1, MMAP_CHECK, BPRM_CHECK, MODULE_CHECK, FIRMWARE_CHECK, POST_SETATTR };
int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask,
int flags);
void ima_init_policy(void);
void ima_update_policy(void);
void ima_update_policy_flag(void);
ssize_t ima_parse_add_rule(char *);
void ima_delete_rules(void);
int ima_check_policy(void);
void *ima_policy_start(struct seq_file *m, loff_t *pos);
void *ima_policy_next(struct seq_file *m, void *v, loff_t *pos);
void ima_policy_stop(struct seq_file *m, void *v);
int ima_policy_show(struct seq_file *m, void *v);
/* Appraise integrity measurements */
#define IMA_APPRAISE_ENFORCE 0x01
#define IMA_APPRAISE_FIX 0x02
#define IMA_APPRAISE_LOG 0x04
#define IMA_APPRAISE_MODULES 0x08
#define IMA_APPRAISE_FIRMWARE 0x10
#ifdef CONFIG_IMA_APPRAISE
int ima_appraise_measurement(int func, struct integrity_iint_cache *iint,
struct file *file, const unsigned char *filename,
struct evm_ima_xattr_data *xattr_value,
int xattr_len, int opened);
int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func);
void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file);
enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint,
int func);
void ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len,
struct ima_digest_data *hash);
int ima_read_xattr(struct dentry *dentry,
struct evm_ima_xattr_data **xattr_value);
#else
static inline int ima_appraise_measurement(int func,
struct integrity_iint_cache *iint,
struct file *file,
const unsigned char *filename,
struct evm_ima_xattr_data *xattr_value,
int xattr_len, int opened)
{
return INTEGRITY_UNKNOWN;
}
static inline int ima_must_appraise(struct inode *inode, int mask,
enum ima_hooks func)
{
return 0;
}
static inline void ima_update_xattr(struct integrity_iint_cache *iint,
struct file *file)
{
}
static inline enum integrity_status ima_get_cache_status(struct integrity_iint_cache
*iint, int func)
{
return INTEGRITY_UNKNOWN;
}
static inline void ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value,
int xattr_len,
struct ima_digest_data *hash)
{
}
static inline int ima_read_xattr(struct dentry *dentry,
struct evm_ima_xattr_data **xattr_value)
{
return 0;
}
#endif
/* LSM based policy rules require audit */
#ifdef CONFIG_IMA_LSM_RULES
#define security_filter_rule_init security_audit_rule_init
#define security_filter_rule_match security_audit_rule_match
#else
static inline int security_filter_rule_init(u32 field, u32 op, char *rulestr,
void **lsmrule)
{
return -EINVAL;
}
static inline int security_filter_rule_match(u32 secid, u32 field, u32 op,
void *lsmrule,
struct audit_context *actx)
{
return -EINVAL;
}
#endif /* CONFIG_IMA_TRUSTED_KEYRING */
#ifdef CONFIG_IMA_READ_POLICY
#define POLICY_FILE_FLAGS (S_IWUSR | S_IRUSR)
#else
#define POLICY_FILE_FLAGS S_IWUSR
#endif /* CONFIG_IMA_WRITE_POLICY */
#endif /* __LINUX_IMA_H */
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