linux/security/integrity/ima/ima.h
Mimi Zohar 1adace9bb0 ima: remove unnecessary call to ima_must_measure
The original ima_must_measure() function based its results on cached
iint information, which required an iint be allocated for all files.
Currently, an iint is allocated only for files in policy.  As a result,
for those files in policy, ima_must_measure() is now called twice: once
to determine if the inode is in the measurement policy and, the second
time, to determine if it needs to be measured/re-measured.

The second call to ima_must_measure() unnecessarily checks to see if
the file is in policy. As we already know the file is in policy, this
patch removes the second unnecessary call to ima_must_measure(), removes
the vestige iint parameter, and just checks the iint directly to determine
if the inode has been measured or needs to be measured/re-measured.

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: Eric Paris <eparis@redhat.com>
2011-02-23 16:38:52 -05:00

159 lines
4.7 KiB
C

/*
* 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>
enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_ASCII };
enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8 };
/* digest size for IMA, fits SHA1 or MD5 */
#define IMA_DIGEST_SIZE 20
#define IMA_EVENT_NAME_LEN_MAX 255
#define IMA_HASH_BITS 9
#define IMA_MEASURE_HTABLE_SIZE (1 << IMA_HASH_BITS)
/* set during initialization */
extern int iint_initialized;
extern int ima_initialized;
extern int ima_used_chip;
extern char *ima_hash;
/* IMA inode template definition */
struct ima_template_data {
u8 digest[IMA_DIGEST_SIZE]; /* sha1/md5 measurement hash */
char file_name[IMA_EVENT_NAME_LEN_MAX + 1]; /* name + \0 */
};
struct ima_template_entry {
u8 digest[IMA_DIGEST_SIZE]; /* sha1 or md5 measurement hash */
const char *template_name;
int template_len;
struct ima_template_data template;
};
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 */
/* declarations */
void integrity_audit_msg(int audit_msgno, struct inode *inode,
const unsigned char *fname, const char *op,
const char *cause, int result, int info);
/* Internal IMA function definitions */
int ima_init(void);
void ima_cleanup(void);
int ima_fs_init(void);
void ima_fs_cleanup(void);
int ima_inode_alloc(struct inode *inode);
int ima_add_template_entry(struct ima_template_entry *entry, int violation,
const char *op, struct inode *inode);
int ima_calc_hash(struct file *file, char *digest);
int ima_calc_template_hash(int template_len, void *template, char *digest);
int ima_calc_boot_aggregate(char *digest);
void ima_add_violation(struct inode *inode, const unsigned char *filename,
const char *op, const char *cause);
/*
* 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);
}
/* iint cache flags */
#define IMA_MEASURED 0x01
/* integrity data associated with an inode */
struct ima_iint_cache {
struct rb_node rb_node; /* rooted in ima_iint_tree */
struct inode *inode; /* back pointer to inode in question */
u64 version; /* track inode changes */
unsigned char flags;
u8 digest[IMA_DIGEST_SIZE];
struct mutex mutex; /* protects: version, flags, digest */
};
/* LIM API function definitions */
int ima_must_measure(struct inode *inode, int mask, int function);
int ima_collect_measurement(struct ima_iint_cache *iint, struct file *file);
void ima_store_measurement(struct ima_iint_cache *iint, struct file *file,
const unsigned char *filename);
int ima_store_template(struct ima_template_entry *entry, int violation,
struct inode *inode);
void ima_template_show(struct seq_file *m, void *e,
enum ima_show_type show);
/* rbtree tree calls to lookup, insert, delete
* integrity data associated with an inode.
*/
struct ima_iint_cache *ima_iint_insert(struct inode *inode);
struct ima_iint_cache *ima_iint_find(struct inode *inode);
/* IMA policy related functions */
enum ima_hooks { FILE_CHECK = 1, FILE_MMAP, BPRM_CHECK };
int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask);
void ima_init_policy(void);
void ima_update_policy(void);
ssize_t ima_parse_add_rule(char *);
void ima_delete_rules(void);
/* 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_LSM_RULES */
#endif