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 iint_initialized;
  39extern int ima_initialized;
  40extern int ima_used_chip;
  41extern char *ima_hash;
  42
  43/* IMA inode template definition */
  44struct ima_template_data {
  45        u8 digest[IMA_DIGEST_SIZE];     /* sha1/md5 measurement hash */
  46        char file_name[IMA_EVENT_NAME_LEN_MAX + 1];     /* name + \0 */
  47};
  48
  49struct ima_template_entry {
  50        u8 digest[IMA_DIGEST_SIZE];     /* sha1 or md5 measurement hash */
  51        const char *template_name;
  52        int template_len;
  53        struct ima_template_data template;
  54};
  55
  56struct ima_queue_entry {
  57        struct hlist_node hnext;        /* place in hash collision list */
  58        struct list_head later;         /* place in ima_measurements list */
  59        struct ima_template_entry *entry;
  60};
  61extern struct list_head ima_measurements;       /* list of all measurements */
  62
  63/* declarations */
  64void integrity_audit_msg(int audit_msgno, struct inode *inode,
  65                         const unsigned char *fname, const char *op,
  66                         const char *cause, int result, int info);
  67
  68/* Internal IMA function definitions */
  69int ima_init(void);
  70void ima_cleanup(void);
  71int ima_fs_init(void);
  72void ima_fs_cleanup(void);
  73int ima_inode_alloc(struct inode *inode);
  74int ima_add_template_entry(struct ima_template_entry *entry, int violation,
  75                           const char *op, struct inode *inode);
  76int ima_calc_hash(struct file *file, char *digest);
  77int ima_calc_template_hash(int template_len, void *template, char *digest);
  78int ima_calc_boot_aggregate(char *digest);
  79void ima_add_violation(struct inode *inode, const unsigned char *filename,
  80                       const char *op, const char *cause);
  81
  82/*
  83 * used to protect h_table and sha_table
  84 */
  85extern spinlock_t ima_queue_lock;
  86
  87struct ima_h_table {
  88        atomic_long_t len;      /* number of stored measurements in the list */
  89        atomic_long_t violations;
  90        struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE];
  91};
  92extern struct ima_h_table ima_htable;
  93
  94static inline unsigned long ima_hash_key(u8 *digest)
  95{
  96        return hash_long(*digest, IMA_HASH_BITS);
  97}
  98
  99/* iint cache flags */
 100#define IMA_MEASURED            0x01
 101
 102/* integrity data associated with an inode */
 103struct ima_iint_cache {
 104        struct rb_node rb_node; /* rooted in ima_iint_tree */
 105        struct inode *inode;    /* back pointer to inode in question */
 106        u64 version;            /* track inode changes */
 107        unsigned char flags;
 108        u8 digest[IMA_DIGEST_SIZE];
 109        struct mutex mutex;     /* protects: version, flags, digest */
 110};
 111
 112/* LIM API function definitions */
 113int ima_must_measure(struct inode *inode, int mask, int function);
 114int ima_collect_measurement(struct ima_iint_cache *iint, struct file *file);
 115void ima_store_measurement(struct ima_iint_cache *iint, struct file *file,
 116                           const unsigned char *filename);
 117int ima_store_template(struct ima_template_entry *entry, int violation,
 118                       struct inode *inode);
 119void ima_template_show(struct seq_file *m, void *e,
 120                       enum ima_show_type show);
 121
 122/* rbtree tree calls to lookup, insert, delete
 123 * integrity data associated with an inode.
 124 */
 125struct ima_iint_cache *ima_iint_insert(struct inode *inode);
 126struct ima_iint_cache *ima_iint_find(struct inode *inode);
 127
 128/* IMA policy related functions */
 129enum ima_hooks { FILE_CHECK = 1, FILE_MMAP, BPRM_CHECK };
 130
 131int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask);
 132void ima_init_policy(void);
 133void ima_update_policy(void);
 134ssize_t ima_parse_add_rule(char *);
 135void ima_delete_rules(void);
 136
 137/* LSM based policy rules require audit */
 138#ifdef CONFIG_IMA_LSM_RULES
 139
 140#define security_filter_rule_init security_audit_rule_init
 141#define security_filter_rule_match security_audit_rule_match
 142
 143#else
 144
 145static inline int security_filter_rule_init(u32 field, u32 op, char *rulestr,
 146                                            void **lsmrule)
 147{
 148        return -EINVAL;
 149}
 150
 151static inline int security_filter_rule_match(u32 secid, u32 field, u32 op,
 152                                             void *lsmrule,
 153                                             struct audit_context *actx)
 154{
 155        return -EINVAL;
 156}
 157#endif /* CONFIG_IMA_LSM_RULES */
 158#endif
 159