LXR linux/security/integrity/ima/ima.h

   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
  27enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_ASCII };
  28enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8 };
  29
  30/* digest size for IMA, fits SHA1 or MD5 */
  31#define IMA_DIGEST_SIZE         20
  32#define IMA_EVENT_NAME_LEN_MAX  255
  33
  34#define IMA_HASH_BITS 9
  35#define IMA_MEASURE_HTABLE_SIZE (1 << IMA_HASH_BITS)
  36
  37/* set during initialization */
  38extern int ima_initialized;
  39extern int ima_used_chip;
  40extern char *ima_hash;
  41
  42/* IMA inode template definition */
  43struct ima_template_data {
  44        u8 digest[IMA_DIGEST_SIZE];     /* sha1/md5 measurement hash */
  45        char file_name[IMA_EVENT_NAME_LEN_MAX + 1];     /* name + \0 */
  46};
  47
  48struct ima_template_entry {
  49        u8 digest[IMA_DIGEST_SIZE];     /* sha1 or md5 measurement hash */
  50        const char *template_name;
  51        int template_len;
  52        struct ima_template_data template;
  53};
  54
  55struct ima_queue_entry {
  56        struct hlist_node hnext;        /* place in hash collision list */
  57        struct list_head later;         /* place in ima_measurements list */
  58        struct ima_template_entry *entry;
  59};
  60extern struct list_head ima_measurements;       /* list of all measurements */
  61
  62/* declarations */
  63void integrity_audit_msg(int audit_msgno, struct inode *inode,
  64                         const unsigned char *fname, const char *op,
  65                         const char *cause, int result, int info);
  66
  67/* Internal IMA function definitions */
  68void ima_iintcache_init(void);
  69int ima_init(void);
  70void ima_cleanup(void);
  71int ima_fs_init(void);
  72void ima_fs_cleanup(void);
  73int ima_add_template_entry(struct ima_template_entry *entry, int violation,
  74                           const char *op, struct inode *inode);
  75int ima_calc_hash(struct file *file, char *digest);
  76int ima_calc_template_hash(int template_len, void *template, char *digest);
  77int ima_calc_boot_aggregate(char *digest);
  78void ima_add_violation(struct inode *inode, const unsigned char *filename,
  79                       const char *op, const char *cause);
  80
  81/*
  82 * used to protect h_table and sha_table
  83 */
  84extern spinlock_t ima_queue_lock;
  85
  86struct ima_h_table {
  87        atomic_long_t len;      /* number of stored measurements in the list */
  88        atomic_long_t violations;
  89        struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE];
  90};
  91extern struct ima_h_table ima_htable;
  92
  93static inline unsigned long ima_hash_key(u8 *digest)
  94{
  95        return hash_long(*digest, IMA_HASH_BITS);
  96}
  97
  98/* iint cache flags */
  99#define IMA_MEASURED            1
 100#define IMA_IINT_DUMP_STACK     512
 101
 102/* integrity data associated with an inode */
 103struct ima_iint_cache {
 104        u64 version;            /* track inode changes */
 105        unsigned long flags;
 106        u8 digest[IMA_DIGEST_SIZE];
 107        struct mutex mutex;     /* protects: version, flags, digest */
 108        long readcount;         /* measured files readcount */
 109        long writecount;        /* measured files writecount */
 110        long opencount;         /* opens reference count */
 111        struct kref refcount;   /* ima_iint_cache reference count */
 112        struct rcu_head rcu;
 113};
 114
 115/* LIM API function definitions */
 116int ima_must_measure(struct ima_iint_cache *iint, struct inode *inode,
 117                     int mask, int function);
 118int ima_collect_measurement(struct ima_iint_cache *iint, struct file *file);
 119void ima_store_measurement(struct ima_iint_cache *iint, struct file *file,
 120                           const unsigned char *filename);
 121int ima_store_template(struct ima_template_entry *entry, int violation,
 122                       struct inode *inode);
 123void ima_template_show(struct seq_file *m, void *e,
 124                       enum ima_show_type show);
 125
 126/* radix tree calls to lookup, insert, delete
 127 * integrity data associated with an inode.
 128 */
 129struct ima_iint_cache *ima_iint_insert(struct inode *inode);
 130struct ima_iint_cache *ima_iint_find_get(struct inode *inode);
 131struct ima_iint_cache *ima_iint_find_insert_get(struct inode *inode);
 132void ima_iint_delete(struct inode *inode);
 133void iint_free(struct kref *kref);
 134void iint_rcu_free(struct rcu_head *rcu);
 135
 136/* IMA policy related functions */
 137enum ima_hooks { PATH_CHECK = 1, FILE_MMAP, BPRM_CHECK };
 138
 139int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask);
 140void ima_init_policy(void);
 141void ima_update_policy(void);
 142int ima_parse_add_rule(char *);
 143void ima_delete_rules(void);
 144
 145/* LSM based policy rules require audit */
 146#ifdef CONFIG_IMA_LSM_RULES
 147
 148#define security_filter_rule_init security_audit_rule_init
 149#define security_filter_rule_match security_audit_rule_match
 150
 151#else
 152
 153static inline int security_filter_rule_init(u32 field, u32 op, char *rulestr,
 154                                            void **lsmrule)
 155{
 156        return -EINVAL;
 157}
 158
 159static inline int security_filter_rule_match(u32 secid, u32 field, u32 op,
 160                                             void *lsmrule,
 161                                             struct audit_context *actx)
 162{
 163        return -EINVAL;
 164}
 165#endif /* CONFIG_IMA_LSM_RULES */
 166#endif
 167