blob: 50d6f798e613390270f99427860c0b28608cb7a9 [file] [log] [blame]
/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2009-2010 IBM Corporation
*
* Authors:
* Mimi Zohar <zohar@us.ibm.com>
*/
#ifdef pr_fmt
#undef pr_fmt
#endif
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/types.h>
#include <linux/integrity.h>
#include <crypto/sha1.h>
#include <crypto/hash.h>
#include <linux/key.h>
#include <linux/audit.h>
#include <linux/lsm_hooks.h>
enum evm_ima_xattr_type {
IMA_XATTR_DIGEST = 0x01,
EVM_XATTR_HMAC,
EVM_IMA_XATTR_DIGSIG,
IMA_XATTR_DIGEST_NG,
EVM_XATTR_PORTABLE_DIGSIG,
IMA_VERITY_DIGSIG,
IMA_XATTR_LAST
};
struct evm_ima_xattr_data {
u8 type;
u8 data[];
} __packed;
/* Only used in the EVM HMAC code. */
struct evm_xattr {
struct evm_ima_xattr_data data;
u8 digest[SHA1_DIGEST_SIZE];
} __packed;
#define IMA_MAX_DIGEST_SIZE HASH_MAX_DIGESTSIZE
struct ima_digest_data {
u8 algo;
u8 length;
union {
struct {
u8 unused;
u8 type;
} sha1;
struct {
u8 type;
u8 algo;
} ng;
u8 data[2];
} xattr;
u8 digest[];
} __packed;
/*
* Instead of wrapping the ima_digest_data struct inside a local structure
* with the maximum hash size, define ima_max_digest_data struct.
*/
struct ima_max_digest_data {
struct ima_digest_data hdr;
u8 digest[HASH_MAX_DIGESTSIZE];
} __packed;
/*
* signature header format v2 - for using with asymmetric keys
*
* The signature_v2_hdr struct includes a signature format version
* to simplify defining new signature formats.
*
* signature format:
* version 2: regular file data hash based signature
* version 3: struct ima_file_id data based signature
*/
struct signature_v2_hdr {
uint8_t type; /* xattr type */
uint8_t version; /* signature format version */
uint8_t hash_algo; /* Digest algorithm [enum hash_algo] */
__be32 keyid; /* IMA key identifier - not X509/PGP specific */
__be16 sig_size; /* signature size */
uint8_t sig[]; /* signature payload */
} __packed;
/*
* IMA signature version 3 disambiguates the data that is signed, by
* indirectly signing the hash of the ima_file_id structure data,
* containing either the fsverity_descriptor struct digest or, in the
* future, the regular IMA file hash.
*
* (The hash of the ima_file_id structure is only of the portion used.)
*/
struct ima_file_id {
__u8 hash_type; /* xattr type [enum evm_ima_xattr_type] */
__u8 hash_algorithm; /* Digest algorithm [enum hash_algo] */
__u8 hash[HASH_MAX_DIGESTSIZE];
} __packed;
int integrity_kernel_read(struct file *file, loff_t offset,
void *addr, unsigned long count);
#define INTEGRITY_KEYRING_EVM 0
#define INTEGRITY_KEYRING_IMA 1
#define INTEGRITY_KEYRING_PLATFORM 2
#define INTEGRITY_KEYRING_MACHINE 3
#define INTEGRITY_KEYRING_MAX 4
extern struct dentry *integrity_dir;
struct modsig;
#ifdef CONFIG_INTEGRITY_SIGNATURE
int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
const char *digest, int digestlen);
int integrity_modsig_verify(unsigned int id, const struct modsig *modsig);
int __init integrity_init_keyring(const unsigned int id);
int __init integrity_load_x509(const unsigned int id, const char *path);
int __init integrity_load_cert(const unsigned int id, const char *source,
const void *data, size_t len, key_perm_t perm);
#else
static inline int integrity_digsig_verify(const unsigned int id,
const char *sig, int siglen,
const char *digest, int digestlen)
{
return -EOPNOTSUPP;
}
static inline int integrity_modsig_verify(unsigned int id,
const struct modsig *modsig)
{
return -EOPNOTSUPP;
}
static inline int integrity_init_keyring(const unsigned int id)
{
return 0;
}
static inline int __init integrity_load_cert(const unsigned int id,
const char *source,
const void *data, size_t len,
key_perm_t perm)
{
return 0;
}
#endif /* CONFIG_INTEGRITY_SIGNATURE */
#ifdef CONFIG_INTEGRITY_ASYMMETRIC_KEYS
int asymmetric_verify(struct key *keyring, const char *sig,
int siglen, const char *data, int datalen);
#else
static inline int asymmetric_verify(struct key *keyring, const char *sig,
int siglen, const char *data, int datalen)
{
return -EOPNOTSUPP;
}
#endif
#ifdef CONFIG_IMA_APPRAISE_MODSIG
int ima_modsig_verify(struct key *keyring, const struct modsig *modsig);
#else
static inline int ima_modsig_verify(struct key *keyring,
const struct modsig *modsig)
{
return -EOPNOTSUPP;
}
#endif
#ifdef CONFIG_IMA_LOAD_X509
void __init ima_load_x509(void);
#else
static inline void ima_load_x509(void)
{
}
#endif
#ifdef CONFIG_EVM_LOAD_X509
void __init evm_load_x509(void);
#else
static inline void evm_load_x509(void)
{
}
#endif
#ifdef CONFIG_INTEGRITY_AUDIT
/* 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);
void integrity_audit_message(int audit_msgno, struct inode *inode,
const unsigned char *fname, const char *op,
const char *cause, int result, int info,
int errno);
static inline struct audit_buffer *
integrity_audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, int type)
{
return audit_log_start(ctx, gfp_mask, type);
}
#else
static inline void integrity_audit_msg(int audit_msgno, struct inode *inode,
const unsigned char *fname,
const char *op, const char *cause,
int result, int info)
{
}
static inline void integrity_audit_message(int audit_msgno,
struct inode *inode,
const unsigned char *fname,
const char *op, const char *cause,
int result, int info, int errno)
{
}
static inline struct audit_buffer *
integrity_audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, int type)
{
return NULL;
}
#endif
#ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING
void __init add_to_platform_keyring(const char *source, const void *data,
size_t len);
#else
static inline void __init add_to_platform_keyring(const char *source,
const void *data, size_t len)
{
}
#endif
#ifdef CONFIG_INTEGRITY_MACHINE_KEYRING
void __init add_to_machine_keyring(const char *source, const void *data, size_t len);
bool __init imputed_trust_enabled(void);
#else
static inline void __init add_to_machine_keyring(const char *source,
const void *data, size_t len)
{
}
static inline bool __init imputed_trust_enabled(void)
{
return false;
}
#endif