/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2005,2006,2007,2008 IBM Corporation
*
* Authors:
* Reiner Sailer <[email protected]>
* Mimi Zohar <[email protected]>
*
* 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/fs.h>
#include <linux/security.h>
#include <linux/hash.h>
#include <linux/tpm.h>
#include <linux/audit.h>
#include <crypto/hash_info.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, TPM_PCR10 = 10 };
/* 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 10
#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"
#define NR_BANKS(chip) ((chip != NULL) ? chip->nr_allocated_banks : 0)
/* current content of the policy */
extern int ima_policy_flag;
/* bitset of digests algorithms allowed in the setxattr hook */
extern atomic_t ima_setxattr_allowed_hash_algorithms;
/* IMA hash algorithm description */
struct ima_algo_desc {
struct crypto_shash *tfm;
enum hash_algo algo;
};
/* set during initialization */
extern int ima_hash_algo __ro_after_init;
extern int ima_sha1_idx __ro_after_init;
extern int ima_hash_algo_idx __ro_after_init;
extern int ima_extra_slots __ro_after_init;
extern struct ima_algo_desc *ima_algo_array __ro_after_init;
extern int ima_appraise;
extern struct tpm_chip *ima_tpm_chip;
extern const char boot_aggregate_name[];
/* IMA event related data */
struct ima_event_data {
struct ima_iint_cache *iint;
struct file *file;
const unsigned char *filename;
struct evm_ima_xattr_data *xattr_value;
int xattr_len;
const struct modsig *modsig;
const char *violation;
const void *buf;
int buf_len;
};
/* 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 {
struct list_head list;
char *name;
char *fmt;
int num_fields;
const struct ima_template_field **fields;
};
struct ima_template_entry {
int pcr;
struct tpm_digest *digests;
struct ima_template_desc *template_desc; /* template descriptor */
u32 template_data_len;
struct ima_field_data template_data[]; /* 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 */
/* Some details preceding the binary serialized measurement list */
struct ima_kexec_hdr {
u16 version;
u16 _reserved0;
u32 _reserved1;
u64 buffer_size;
u64 count;
};
/* IMA iint action cache flags */
#define IMA_MEASURE 0x00000001
#define IMA_MEASURED 0x00000002
#define IMA_APPRAISE 0x00000004
#define IMA_APPRAISED 0x00000008
/*#define IMA_COLLECT 0x00000010 do not use this flag */
#define IMA_COLLECTED 0x00000020
#define IMA_AUDIT 0x00000040
#define IMA_AUDITED 0x00000080
#define IMA_HASH 0x00000100
#define IMA_HASHED 0x00000200
/* IMA iint policy rule cache flags */
#define IMA_NONACTION_FLAGS 0xff000000
#define IMA_DIGSIG_REQUIRED 0x01000000
#define IMA_PERMIT_DIRECTIO 0x02000000
#define IMA_NEW_FILE 0x04000000
#define IMA_FAIL_UNVERIFIABLE_SIGS 0x10000000
#define IMA_MODSIG_ALLOWED 0x20000000
#define IMA_CHECK_BLACKLIST 0x40000000
#define IMA_VERITY_REQUIRED 0x80000000
#define IMA_DO_MASK (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \
IMA_HASH | IMA_APPRAISE_SUBMASK)
#define IMA_DONE_MASK (IMA_MEASURED | IMA_APPRAISED | IMA_AUDITED | \
IMA_HASHED | IMA_COLLECTED | \
IMA_APPRAISED_SUBMASK)
/* IMA iint subaction appraise cache flags */
#define IMA_FILE_APPRAISE 0x00001000
#define IMA_FILE_APPRAISED 0x00002000
#define IMA_MMAP_APPRAISE 0x00004000
#define IMA_MMAP_APPRAISED 0x00008000
#define IMA_BPRM_APPRAISE 0x00010000
#define IMA_BPRM_APPRAISED 0x00020000
#define IMA_READ_APPRAISE 0x00040000
#define IMA_READ_APPRAISED 0x00080000
#define IMA_CREDS_APPRAISE 0x00100000
#define IMA_CREDS_APPRAISED 0x00200000
#define IMA_APPRAISE_SUBMASK (IMA_FILE_APPRAISE | IMA_MMAP_APPRAISE | \
IMA_BPRM_APPRAISE | IMA_READ_APPRAISE | \
IMA_CREDS_APPRAISE)
#define IMA_APPRAISED_SUBMASK (IMA_FILE_APPRAISED | IMA_MMAP_APPRAISED | \
IMA_BPRM_APPRAISED | IMA_READ_APPRAISED | \
IMA_CREDS_APPRAISED)
/* IMA iint cache atomic_flags */
#define IMA_CHANGE_XATTR 0
#define IMA_UPDATE_XATTR 1
#define IMA_CHANGE_ATTR 2
#define IMA_DIGSIG 3
#define IMA_MUST_MEASURE 4
/* IMA integrity metadata associated with an inode */
struct ima_iint_cache {
struct mutex mutex; /* protects: version, flags, digest */
struct integrity_inode_attributes real_inode;
unsigned long flags;
unsigned long measured_pcrs;
unsigned long atomic_flags;
enum integrity_status ima_file_status:4;
enum integrity_status ima_mmap_status:4;
enum integrity_status ima_bprm_status:4;
enum integrity_status ima_read_status:4;
enum integrity_status ima_creds_status:4;
struct ima_digest_data *ima_hash;
};
extern struct lsm_blob_sizes ima_blob_sizes;
static inline struct ima_iint_cache *
ima_inode_get_iint(const struct inode *inode)
{
struct ima_iint_cache **iint_sec;
if (unlikely(!inode->i_security))
return NULL;
iint_sec = inode->i_security + ima_blob_sizes.lbs_inode;
return *iint_sec;
}
static inline void ima_inode_set_iint(const struct inode *inode,
struct ima_iint_cache *iint)
{
struct ima_iint_cache **iint_sec;
if (unlikely(!inode->i_security))
return;
iint_sec = inode->i_security + ima_blob_sizes.lbs_inode;
*iint_sec = iint;
}
struct ima_iint_cache *ima_iint_find(struct inode *inode);
struct ima_iint_cache *ima_inode_get(struct inode *inode);
void ima_inode_free_rcu(void *inode_security);
void __init ima_iintcache_init(void);
extern const int read_idmap[];
#ifdef CONFIG_HAVE_IMA_KEXEC
void ima_load_kexec_buffer(void);
#else
static inline void ima_load_kexec_buffer(void) {}
#endif /* CONFIG_HAVE_IMA_KEXEC */
#ifdef CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS
void ima_post_key_create_or_update(struct key *keyring, struct key *key,
const void *payload, size_t plen,
unsigned long flags, bool create);
#endif
/*
* The default binary_runtime_measurements list format is defined as the
* platform native format. The canonical format is defined as little-endian.
*/
extern bool ima_canonical_fmt;
/* 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_buffer_hash(const void *buf, loff_t len,
struct ima_digest_data *hash);
int ima_calc_field_array_hash(struct ima_field_data *field_data,
struct ima_template_entry *entry);
int ima_calc_boot_aggregate(struct ima_digest_data *hash);
void ima_add_violation(struct file *file, const unsigned char *filename,
struct ima_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);
int template_desc_init_fields(const char *template_fmt,
const struct ima_template_field ***fields,
int *num_fields);
struct ima_template_desc *ima_template_desc_current(void);
struct ima_template_desc *ima_template_desc_buf(void);
struct ima_template_desc *lookup_template_desc(const char *name);
bool ima_template_has_modsig(const struct ima_template_desc *ima_template);
int ima_restore_measurement_entry(struct ima_template_entry *entry);
int ima_restore_measurement_list(loff_t bufsize, void *buf);
int ima_measurements_show(struct seq_file *m, void *v);
unsigned long ima_get_binary_runtime_size(void);
int ima_init_template(void);
void ima_init_template_list(void);
int __init ima_init_digests(void);
int ima_lsm_policy_change(struct notifier_block *nb, unsigned long event,
void *lsm_data);
/*
* 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 int ima_hash_key(u8 *digest)
{
/* there is no point in taking a hash of part of a digest */
return (digest[0] | digest[1] << 8) % IMA_MEASURE_HTABLE_SIZE;
}
#define __ima_hooks(hook) \
hook(NONE, none) \
hook(FILE_CHECK, file) \
hook(MMAP_CHECK, mmap) \
hook(MMAP_CHECK_REQPROT, mmap_reqprot) \
hook(BPRM_CHECK, bprm) \
hook(CREDS_CHECK, creds) \
hook(POST_SETATTR, post_setattr) \
hook(MODULE_CHECK, module) \
hook(FIRMWARE_CHECK, firmware) \
hook(KEXEC_KERNEL_CHECK, kexec_kernel) \
hook(KEXEC_INITRAMFS_CHECK, kexec_initramfs) \
hook(POLICY_CHECK, policy) \
hook(KEXEC_CMDLINE, kexec_cmdline) \
hook(KEY_CHECK, key) \
hook(CRITICAL_DATA, critical_data) \
hook(SETXATTR_CHECK, setxattr_check) \
hook(MAX_CHECK, none)
#define __ima_hook_enumify(ENUM, str) ENUM,
#define __ima_stringify(arg) (#arg)
#define __ima_hook_measuring_stringify(ENUM, str) \
(__ima_stringify(measuring_ ##str)),
enum ima_hooks {
__ima_hooks(__ima_hook_enumify)
};
static const char * const ima_hooks_measure_str[] = {
__ima_hooks(__ima_hook_measuring_stringify)
};
static inline const char *func_measure_str(enum ima_hooks func)
{
if (func >= MAX_CHECK)
return ima_hooks_measure_str[NONE];
return ima_hooks_measure_str[func];
}
extern const char *const func_tokens[];
struct modsig;
#ifdef CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS
/*
* To track keys that need to be measured.
*/
struct ima_key_entry {
struct list_head list;
void *payload;
size_t payload_len;
char *keyring_name;
};
void ima_init_key_queue(void);
bool ima_should_queue_key(void);
bool ima_queue_key(struct key *keyring, const void *payload,
size_t payload_len);
void ima_process_queued_keys(void);
#else
static inline void ima_init_key_queue(void) {}
static inline bool ima_should_queue_key(void) { return false; }
static inline bool ima_queue_key(struct key *keyring,
const void *payload,
size_t payload_len) { return false; }
static inline void ima_process_queued_keys(void) {}
#endif /* CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS */
/* LIM API function definitions */
int ima_get_action(struct mnt_idmap *idmap, struct inode *inode,
const struct cred *cred, u32 secid, int mask,
enum ima_hooks func, int *pcr,
struct ima_template_desc **template_desc,
const char *func_data, unsigned int *allowed_algos);
int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func);
int ima_collect_measurement(struct ima_iint_cache *iint, struct file *file,
void *buf, loff_t size, enum hash_algo algo,
struct modsig *modsig);
void ima_store_measurement(struct ima_iint_cache *iint, struct file *file,
const unsigned char *filename,
struct evm_ima_xattr_data *xattr_value,
int xattr_len, const struct modsig *modsig, int pcr,
struct ima_template_desc *template_desc);
int process_buffer_measurement(struct mnt_idmap *idmap,
struct inode *inode, const void *buf, int size,
const char *eventname, enum ima_hooks func,
int pcr, const char *func_data,
bool buf_hash, u8 *digest, size_t digest_len);
void ima_audit_measurement(struct ima_iint_cache *iint,
const unsigned char *filename);
int ima_alloc_init_template(struct ima_event_data *event_data,
struct ima_template_entry **entry,
struct ima_template_desc *template_desc);
int ima_store_template(struct ima_template_entry *entry, int violation,
struct inode *inode,
const unsigned char *filename, int pcr);
void ima_free_template_entry(struct ima_template_entry *entry);
const char *ima_d_path(const struct path *path, char **pathbuf, char *filename);
/* IMA policy related functions */
int ima_match_policy(struct mnt_idmap *idmap, struct inode *inode,
const struct cred *cred, u32 secid, enum ima_hooks func,
int mask, int flags, int *pcr,
struct ima_template_desc **template_desc,
const char *func_data, unsigned int *allowed_algos);
void ima_init_policy(void);
void ima_update_policy(void);
void ima_update_policy_flags(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
#define IMA_APPRAISE_POLICY 0x20
#define IMA_APPRAISE_KEXEC 0x40
#ifdef CONFIG_IMA_APPRAISE
int ima_check_blacklist(struct ima_iint_cache *iint,
const struct modsig *modsig, int pcr);
int ima_appraise_measurement(enum ima_hooks func, struct ima_iint_cache *iint,
struct file *file, const unsigned char *filename,
struct evm_ima_xattr_data *xattr_value,
int xattr_len, const struct modsig *modsig);
int ima_must_appraise(struct mnt_idmap *idmap, struct inode *inode,
int mask, enum ima_hooks func);
void ima_update_xattr(struct ima_iint_cache *iint, struct file *file);
enum integrity_status ima_get_cache_status(struct ima_iint_cache *iint,
enum ima_hooks func);
enum hash_algo ima_get_hash_algo(const struct evm_ima_xattr_data *xattr_value,
int xattr_len);
int ima_read_xattr(struct dentry *dentry,
struct evm_ima_xattr_data **xattr_value, int xattr_len);
void __init init_ima_appraise_lsm(const struct lsm_id *lsmid);
#else
static inline int ima_check_blacklist(struct ima_iint_cache *iint,
const struct modsig *modsig, int pcr)
{
return 0;
}
static inline int ima_appraise_measurement(enum ima_hooks func,
struct ima_iint_cache *iint,
struct file *file,
const unsigned char *filename,
struct evm_ima_xattr_data *xattr_value,
int xattr_len,
const struct modsig *modsig)
{
return INTEGRITY_UNKNOWN;
}
static inline int ima_must_appraise(struct mnt_idmap *idmap,
struct inode *inode, int mask,
enum ima_hooks func)
{
return 0;
}
static inline void ima_update_xattr(struct ima_iint_cache *iint,
struct file *file)
{
}
static inline enum integrity_status
ima_get_cache_status(struct ima_iint_cache *iint, enum ima_hooks func)
{
return INTEGRITY_UNKNOWN;
}
static inline enum hash_algo
ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len)
{
return ima_hash_algo;
}
static inline int ima_read_xattr(struct dentry *dentry,
struct evm_ima_xattr_data **xattr_value,
int xattr_len)
{
return 0;
}
static inline void __init init_ima_appraise_lsm(const struct lsm_id *lsmid)
{
}
#endif /* CONFIG_IMA_APPRAISE */
#ifdef CONFIG_IMA_APPRAISE_MODSIG
int ima_read_modsig(enum ima_hooks func, const void *buf, loff_t buf_len,
struct modsig **modsig);
void ima_collect_modsig(struct modsig *modsig, const void *buf, loff_t size);
int ima_get_modsig_digest(const struct modsig *modsig, enum hash_algo *algo,
const u8 **digest, u32 *digest_size);
int ima_get_raw_modsig(const struct modsig *modsig, const void **data,
u32 *data_len);
void ima_free_modsig(struct modsig *modsig);
#else
static inline int ima_read_modsig(enum ima_hooks func, const void *buf,
loff_t buf_len, struct modsig **modsig)
{
return -EOPNOTSUPP;
}
static inline void ima_collect_modsig(struct modsig *modsig, const void *buf,
loff_t size)
{
}
static inline int ima_get_modsig_digest(const struct modsig *modsig,
enum hash_algo *algo, const u8 **digest,
u32 *digest_size)
{
return -EOPNOTSUPP;
}
static inline int ima_get_raw_modsig(const struct modsig *modsig,
const void **data, u32 *data_len)
{
return -EOPNOTSUPP;
}
static inline void ima_free_modsig(struct modsig *modsig)
{
}
#endif /* CONFIG_IMA_APPRAISE_MODSIG */
/* LSM based policy rules require audit */
#ifdef CONFIG_IMA_LSM_RULES
#define ima_filter_rule_init security_audit_rule_init
#define ima_filter_rule_free security_audit_rule_free
#define ima_filter_rule_match security_audit_rule_match
#else
static inline int ima_filter_rule_init(u32 field, u32 op, char *rulestr,
void **lsmrule, gfp_t gfp)
{
return -EINVAL;
}
static inline void ima_filter_rule_free(void *lsmrule)
{
}
static inline int ima_filter_rule_match(u32 secid, u32 field, u32 op,
void *lsmrule)
{
return -EINVAL;
}
#endif /* CONFIG_IMA_LSM_RULES */
#ifdef CONFIG_IMA_READ_POLICY
#define POLICY_FILE_FLAGS (S_IWUSR | S_IRUSR)
#else
#define POLICY_FILE_FLAGS S_IWUSR
#endif /* CONFIG_IMA_READ_POLICY */
#endif /* __LINUX_IMA_H */
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